Sample records for pre-tmin flow treatment

  1. Using Pre-TMIn Treatment to Improve the Optical Properties of Green Light Emitting Diodes

    Directory of Open Access Journals (Sweden)

    Bing Xu


    Full Text Available We investigated the effects of pre-TMIn treatment on the optical properties of green light emitting diodes (LEDs. Although pre-TMIn treatment did not affect the epitaxial structure of quantum wells, it significantly improved the quality of the surface morphology relative to that of the untreated sample. Indium cluster can be seen by high-resolution transmission electron microscopy (HR-TEM, which is the explanation for the red-shift of photoluminescence (PL. Time-resolved photoluminescence measurements indicated that the sample prepared with pre-TMIn treatment had a shorter radiative decay time. As a result, the light output power of the treated green LED was higher than that of the conventional untreated one. Thus, pre-TMIn treatment appears to be a simple and efficient means of improving the performance of green LEDs.

  2. Influence of Pre-trimethylindium flow treatment on blue light emitting diode

    International Nuclear Information System (INIS)

    Xu, Bing; Zhao, Jun Liang; Dai, Hai Tao; Wang, Shu Guo; Lin, Ray-Ming; Chu, Fu-Chuan; Huang, Chou-Hsiung; Yu, Sheng-Fu; Sun, Xiao Wei


    The effects of Pre-trimethylindium (TMIn) flow treatment prior to quantum well growth on blue light emitting diode properties were investigated. High-resolution X-ray diffraction indicated that Pre-TMIn flow treatment did not change the composition of indium in quantum wells, but influenced electrical and optical properties of blue light emitting diode. Electroluminescence exhibited redshift with increasing TMIn treatment time. Though, the forward voltage became a little larger with longer Pre-TMIn treatment time due to the slight phase separation and indium aggregation, the efficiency droop of the device was improved effectively. - Highlights: • Pre-trimethylindium treatment can lead to longer wavelength. • External quantum efficiency can be improved effectively. • Electrical properties are not decreased using Pre-trimethylindium treatment

  3. Influence of Pre-trimethylindium flow treatment on blue light emitting diode

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Bing; Zhao, Jun Liang [Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology, School of Science, Tianjin University, Tianjin 300072 (China); Dai, Hai Tao, E-mail: [Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology, School of Science, Tianjin University, Tianjin 300072 (China); Wang, Shu Guo [Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology, School of Science, Tianjin University, Tianjin 300072 (China); Lin, Ray-Ming, E-mail: [Graduate Institute of Electronic Engineering and Green Technology Research Center, Chang Gung University, Taoyuan 333, Taiwan (China); Chu, Fu-Chuan; Huang, Chou-Hsiung [Graduate Institute of Electronic Engineering and Green Technology Research Center, Chang Gung University, Taoyuan 333, Taiwan (China); Yu, Sheng-Fu [Institute of Microelectronics and Department of Electrical Engineering, Center for Micro/Nano Science and Technology, Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 70101, Taiwan (China); Sun, Xiao Wei, E-mail: [South University of Science and Technology of China, Shenzhen, Guangdong (China)


    The effects of Pre-trimethylindium (TMIn) flow treatment prior to quantum well growth on blue light emitting diode properties were investigated. High-resolution X-ray diffraction indicated that Pre-TMIn flow treatment did not change the composition of indium in quantum wells, but influenced electrical and optical properties of blue light emitting diode. Electroluminescence exhibited redshift with increasing TMIn treatment time. Though, the forward voltage became a little larger with longer Pre-TMIn treatment time due to the slight phase separation and indium aggregation, the efficiency droop of the device was improved effectively. - Highlights: • Pre-trimethylindium treatment can lead to longer wavelength. • External quantum efficiency can be improved effectively. • Electrical properties are not decreased using Pre-trimethylindium treatment.

  4. Endovascular Treatment of AICA Flow Dependent Aneurysms (United States)

    Mahmoud, M.; El Serwi, A.; Alaa Habib, M.; Abou Gamrah, S.


    Summary Peripheral anterior inferior cerebellar artery (AICA) aneurysms are rare, accounting for less than 1% of all cerebral aneurysms. To our knowledge 34 flow-related cases including the present study have been reported in the literature. Three patients harbouring four flow dependent aneurysms were referred to our institution. Two patients presented with subarachnoid hemorrhage, one presented with cerebellar manifestations. They were all treated by endovascular embolization of the aneurysm as well as the parent artery using liquid embolic material. Two cases were embolized using NBCA, Onyx was used in the third case. No bleeding or rebleeding were encountered during the follow-up period which ranged from five to nine months. One patient developed facial palsy, cerebellar symptoms and sensorineural hearing loss. The remaining two cases did not develop any post treatment neurological complications. Endovascular management of flow-dependent AICA aneurysms by parent artery occlusion is feasible and efficient in terms of rebleeding prevention. Post embolization neurological complications are unpredictable. This depends upon the adequacy of collaterals from other cerebellar arteries. PMID:23217640

  5. Successful treatment of high-flow priapism with radiologic ...

    African Journals Online (AJOL)

    occlusive, low flow) painful priapism and nonischemic (arterial, high flow) painless priapism.. We report our successful treatment of arterial priapism by means of radiologic selective transcatheter embolization of the internal pudendal artery using micro ...

  6. Passive flow regulators for drug delivery and hydrocephalus treatment (United States)

    Chappel, E.; Dumont-Fillon, D.; Mefti, S.


    Passive flow regulators are usually intended to deliver or drain a fluid at a constant rate independently from pressure variations. New designs of passive flow regulators made of a stack of a silicon membrane anodically bonded to a Pyrex substrate are proposed. A first design has been built for the derivation of cerebrospinal fluid (CSF) towards peritoneum for hydrocephalus treatment. The device allows draining CSF at the patient production rate independently from postural changes. The flow rate is regulated at 20 ml/h in the range 10 to 40 mbar. Specific features to adjust in vivo the nominal flow rate are shown. A second design including high pressure shut-off feature has been made. The intended use is drug delivery with pressurized reservoir of typically 100 to 300 mbar. In both cases, the membrane comprises several holes facing pillars in the Pyrex substrate. These pillars are machined in a cavity which ensures a gap between the membrane and the pillars at rest. The fluid in the pressurized reservoir is directly in contact with the top surface of the membrane, inducing its deflection towards Pyrex substrate and closing progressively the fluidic pathway through each hole of the membrane. Since the membrane deflection is highly non-linear, FEM simulations have been performed to determine both radial position and diameter of the membrane holes that ensure a constant flow rate for a given range of pressure.

  7. Battery related cobalt and REE flows in WEEE treatment. (United States)

    Sommer, P; Rotter, V S; Ueberschaar, M


    In batteries associated with waste electrical and electronic equipment (WEEE), battery systems can be found with a higher content of valuable and critical raw materials like cobalt and rare earth elements (REE) relative to the general mix of portable batteries. Based on a material flow model, this study estimates the flows of REE and cobalt associated to WEEE and the fate of these metals in the end-of-life systems. In 2011, approximately 40 Mg REE and 325 Mg cobalt were disposed of with WEEE-batteries. The end-of-life recycling rate for cobalt was 14%, for REE 0%. The volume of waste batteries can be expected to grow, but variation in the battery composition makes it difficult to forecast the future secondary raw material potential. Nevertheless, product specific treatment strategies ought to be implemented throughout the stages of the value chain. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Dewatering and Treatment of Septage Using Vertical Flow Constructed Wetlands

    Directory of Open Access Journals (Sweden)

    Yee Yong Tan


    Full Text Available The vertical flow constructed wetland (VFCW has become an attractive decentralised technology for septage treatment. One of the main purposes of the septage treatment is to reduce the volume of raw septage through dewatering, where the solids content is retained in the wetland bed and the water content is released. The retention of solids forms a layer of sludge deposit at the wetland surface, and the drained water, the so-called leachate, typically contains a lower solids content. This article reports the performance of dewatering and filtration of a pilot-scale VFCW designed for septage treatment. A comparison between two feeding strategies, hydraulic loading rate (HLR and solids loading rate (SLR, is presented. The dewatering efficiency through drainage was found to be dependent on the solids load. The removal of total solids (TS and chemical oxygen demand (COD were excellent as the quality of leachate showed that more than 90% of TS and COD were retained in the system. This study reveals that the feeding based on SLR delivered a more sustainable performance for dewatering and solids removal. The build-up of sludge deposit significantly deteriorated the dewatering efficiency through drainage, but it tended to improve the filtration capacity.

  9. Treatment of volatile organic contaminants in a vertical flow filter: Relevance of different removal processes

    NARCIS (Netherlands)

    De Biase, C.; Reger, D.; Schmidt, A.; Jechalke, S.; Reiche, N.; Martínez-Lavanchy, P.M.; Rosell, M.; Van Afferden, M.; Maier, U.; Oswald, S.E.; Thullner, M.


    Vertical flow filters and vertical flow constructed wetlands are established wastewater treatment systems and have also been proposed for the treatment of contaminated groundwater. This study investigates the removal processes of volatile organic compounds in a pilot-scale vertical flow filter.

  10. Flow-diverting stents for the treatment of arterial aneurysms. (United States)

    Sfyroeras, George S; Dalainas, Ilias; Giannakopoulos, Triantafyllos G; Antonopoulos, Konstantinos; Kakisis, John D; Liapis, Christos D


    Anatomic factors may limit the application of stent grafts for the treatment of arterial aneurysms. Flow- diverting stents (FDSs) are specially designed to reduce flow velocity in the aneurysm sac and promote thrombosis while maintaining flow in the main artery and branch vessels. FDSs include the Pipeline Embolization Device (ev3, Plymouth, Minn), the SILK Arterial Reconstruction Device (Balt Extrusion, Montmorency, France), and the Cardiatis Multilayer Stent (Cardiatis, Isnes, Belgium). The first two have been mainly used for the treatment of intracranial aneurysms. The aim of this study was to review the current role of FDSs in the treatment of extracranial arterial aneurysms. A systematic electronic health database search was conducted using PubMed, Ovid, Medline, and the Cochrane Database on all accessible published articles through March 2012. An additional search for abstracts presented in international congresses for vascular surgery was also performed. Full-text articles and abstracts were analyzed separately due to the heterogeneity of the data. Results of the use of FDSs in arterial aneurysms were reported in 12 full-text articles including 35 patients (26 men, age 65.4) with 38 aneurysms. The aneurysms were located in the hepatic (n = 12), splenic (n = 6), renal (n = 5), celiac (n = 4), superior mesenteric (n = 3), subclavian (n = 2), gastroduodenal (n = 1), and popliteal arteries (n = 1) and in the descending thoracic (n = 1), suprarenal (n = 1) and infrarenal aorta (n = 2). The 30-day mortality was 5.7% (2 of 35 patients). Three stent thromboses occurred (8.3%), none of them with clinical consequences. Thirty patients with 33 aneurysms and patent FDSs were monitored for an average of 9.2 months. Thrombosis occurred in 90.6%, and volume reduction was observed in 81% of the aneurysms. No branch vessel occlusion occurred. Twelve abstracts were identified, including 133 patients (mean age, 64.7 years). They included 62 peripheral, 28 visceral, and 43

  11. Application of subsurface vertical flow constructed wetlands to reject water treatment in dairy wastewater treatment plant. (United States)

    Dąbrowski, Wojciech; Karolinczak, Beata; Gajewska, Magdalena; Wojciechowska, Ewa


    The paper presents the effects of applying subsurface vertical flow constructed wetlands (SS VF) for the treatment of reject water generated in the process of aerobic sewage sludge stabilization in the biggest dairy wastewater treatment plant (WWTP) in Poland. Two SS VF beds were built: bed (A) with 0.65 m depth and bed (B) with 1.0 m depth, planted with reeds. Beds were fed with reject water with hydraulic load of 0.1 m d -1 in order to establish the differences in treatment efficiency. During an eight-months research period, a high removal efficiency of predominant pollutants was shown: BOD 5 88.1% (A) and 90.5% (B); COD 84.5% (A) and 87.5% (B); TSS 87.6% (A) and 91.9% (B); TKN 82.4% (A) and 76.5% (B); N-NH 4 + 89.2% (A) and 85.7% (B); TP 30.2% (A) and 40.6% (B). There were not statistically significant differences in the removal efficiencies between bed (B) with 1.0 m depth and bed (A) with 0.65 m depth. The research indicated that SS VF beds could be successfully applied to reject water treatment in dairy WWTPs. The study proved that the use of SS VF beds in full scale in dairy WWTPs would result in a significant decrease in pollutants' load in reject water. In the analyzed case, decreasing the load of ammonia nitrogen was of greatest importance, as it constituted 58% of the total load treated in dairy WWTP and posed a hazard to the stability of the treatment process.

  12. Treatment of swine wastewater with subsurface-flow constructed ...

    African Journals Online (AJOL)

    This study evaluates the capability of horizontal subsurface-flow constructed wetlands (SSF CWs) for treating pretreated swine wastewater as a function of contact time (CT) and type of macrophyte under the local conditions of Yucatán, Mexico. Experiments were conducted from July 2004 to November 2005 on a ...

  13. Modeling a novel glass immobilization waste treatment process using flow

    International Nuclear Information System (INIS)

    Ferrada, J.J.; Nehls, J.W. Jr.; Welch, T.D.; Giardina, J.L.


    One option for control and disposal of surplus fissile materials is the Glass Material Oxidation and Dissolution System (GMODS), a process developed at ORNL for directly converting Pu-bearing material into a durable high-quality glass waste form. This paper presents a preliminary assessment of the GMODS process flowsheet using FLOW, a chemical process simulator. The simulation showed that the glass chemistry postulated ion the models has acceptable levels of risks

  14. Application of double-layered skin phantoms for optical flow imaging during laser tattoo treatments (United States)

    Lee, Byeong-il; Song, Woosub; Kim, Hyejin; Kang, Hyun Wook


    The feasible application of double-layered skin phantoms was evaluated to identify artificial blood flow with a Doppler optical coherence tomography (DOCT) system for laser tattoo treatments. Polydimethylsiloxane (PDMS) was used to fabricate the artificial phantoms with flow channels embedded. A double-integrating sphere system with an inverse adding-doubling method quantified both the absorption and the reduced scattering coefficients for epidermis and dermis phantoms. Both OCT and caliper measurements confirmed the double-layered phantom structure (epidermis = 136 ± 17 µm vs. dermis = 3.0 ± 0.1 mm). The DOCT method demonstrated that high flow rates were associated with high image contrast, visualizing the position and the shape of the flow channel. Application of the channel-embedded skin phantoms in conjunction with DOCT can be a reliable technique to assess dynamic variations in the blood flow during and after laser tattoo treatments.

  15. [Flows between modalities in the treatment of ESRD]. (United States)

    Labeeuw, M; Couchoud, C


    This chapter provides indicators to describe the outcome of prevalent and incident patients in the various modalities of treatment. Among the 36 849 patients on dialysis at 31/10/2010, 79% were already on RRT at 31/12/2009. Respectively 91%, 85% and 93% of the patients on HD in-center, HD self-care unit and peritoneal dialysis were in the same modality of treatment the year before. Among the 29 758 patients with a functioning graft at 31/12/2010, 98% were already on RRT at 31/12/2009, 95% of them with a functioning graft. 72%, 72% and 74% of the patients with in-center HD, outcenter HD and self-care unit were in the same modality of treatment at 31/12/2011. But 37% of the patients on PD at 31/12/2010 were not on PD at 31/12/2011. In 2011, new patients represented 89% of the entries in peritoneal dialysis. Renal transplantation represented 10% of the outcomes of the HD patients in self-care unit or at home. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  16. Hypogonadotropic hypogonadism: new identification of testicular blood flow and varicocele after treatment with gonadotropins. (United States)

    ur Rehman, Khaleeq; Shahid, Khubaib; Humayun, Hina


    To investigate testicular changes in patients with hypogonadotropic hypogonadism (HH) after treatment with gonadotropins. Patients with HH were investigated and followed before and after treatment. Urology and andrology clinic of a teaching hospital. Consecutive male patients with diagnosed HH. All patients were treated with gonadotropins during the study period and later. The hormonal status and scrotal color Doppler ultrasound (CDUS) of patients was recorded before and after treatment. Twenty-six patients with HH (ages 18-43 years) were followed for 8-29 months. After treatment, serum T and secondary sex characters improved in all and spermatogenesis developed in 61.5% of patients. Before treatment, testicular (intraparenchymal blood flow) was undetectable in all and barely detectable in three patients. This improved significantly to 4.53±5.44 and 4.27±4.97 cm/second, respectively, after treatment. Subcapsular arterial flow and testicular size also improved significantly. Similarly, after treatment, transverse epididymal diameter (TED) increased significantly. At baseline, no patient had detectable varicocele on CDUS. After treatment, varicocele was demonstrable in 23% of patients. This finding was further evaluated retrospectively from our 76 HH patient files. None of them had varicocele before treatment, but after treatment 19.73% were found to have varicocele. Patients with HH responded to gonadotropins by improvement in testicular blood flow and increase in TED. In some patients, varicocele was found to develop after treatment. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  17. A matrix-free implicit treatment for all speed flows on unstructured grids

    International Nuclear Information System (INIS)

    Kloczko, Th.


    The aim of this research work is the development of an efficient implicit scheme for computing compressible and low-speed flows on unstructured meshes. The first part is devoted to the review and analysis of some standard block-implicit treatments for the two-dimensional Euler and Navier-Stokes equations with a view to identify the best candidate for a fair comparison with the matrix-free treatment. The second part forms the main original contribution of this research work. It describes and analyses a matrix-free treatment that can be applied to any type of flow (inviscid/viscous, low Mach/highly compressible, steady/unsteady). The third part deals with the implementation of this treatment within the CAST3M code, and the demonstration of its advantages over existing techniques for computing applications of interest for the CEA: low-Mach number steady and unsteady flows in a Tee junction for example

  18. Bedrock refractive-flow cells: A passive treatment analog to funnel-and-gate

    International Nuclear Information System (INIS)

    Dick, V.; Edwards, D.


    Funnel-and-gate technology provides a mechanism to passively treat groundwater contaminant plumes, but depends on placement of a sufficient barrier (open-quotes funnelclose quotes) in the plume flow path to channel the plume to a pass-through treatment zone (open-quotes gateclose quotes). Conventional barrier technologies limit funnel-and-gate deployment to unconsolidated overburden applications. A method has been developed which allows similar passive treatment to be applied to bedrock plumes. Rather than use barriers as the funnel, the method uses engineered bedrock zones, installed via precision blasting or other means, to refract groundwater flow along a preferred path to treatment (gate). The method requires orienting the refractive cell based on the Tangent Law and extending refractive cell limbs down gradient of the gate to disperse head and control flow. A typical Refractive-Flow cell may be open-quotes Yclose quotesshaped, with each limb 3-10 ft [1-3 m] wide and several tens to a few hundred feet [10 - 100 m] in length. Treatment takes place at the center of the X. MODFLOW modeling has been used to successfully simulate desired flow. Engineered blasting has been used at full scale application to create bedrock rubble zones for active collection/flow control for several years. The method provides a previously unavailable method to passively treat contaminated groundwater in bedrock at low cost

  19. Applications of Continuous-Flow Photochemistry in Organic Synthesis, Material Science, and Water Treatment. (United States)

    Cambié, Dario; Bottecchia, Cecilia; Straathof, Natan J W; Hessel, Volker; Noël, Timothy


    Continuous-flow photochemistry in microreactors receives a lot of attention from researchers in academia and industry as this technology provides reduced reaction times, higher selectivities, straightforward scalability, and the possibility to safely use hazardous intermediates and gaseous reactants. In this review, an up-to-date overview is given of photochemical transformations in continuous-flow reactors, including applications in organic synthesis, material science, and water treatment. In addition, the advantages of continuous-flow photochemistry are pointed out and a thorough comparison with batch processing is presented.

  20. Immediate Flow Disruption as a Prognostic Factor after Flow Diverter Treatment: Long-term Experience with the Pipeline Embolization Device. (United States)

    Dodier, Philippe; Frischer, Josa M; Wang, Wei-Te; Auzinger, Thomas; Mallouhi, Ammar; Serles, Wolfgang; Gruber, Andreas; Knosp, Engelbert; Bavinzski, Gerhard


    The authors report long-term results after PED implantation, characterize complex and standard aneurysms comprehensively and introduce a modified flow disruption scale. The authors retrospectively reviewed a consecutive series of 40 patients, harboring 59 aneurysms treated with 54 PEDs. Aneurysm complexity was assessed using our proposed classification. Immediate angiographic results were analyzed using previously published grading scales and our novel flow disruption scale (BD scale). Forty-six (78%) aneurysms were classified as complex according to our new definition. The vast majority of PED interventions was performed in the paraophthalmic and cavernous ICA segments. Excellent neurological outcome (mRS 0 and 1) was observed in 94% of patients. Our data demonstrate low permanent procedure-related mortality (0%) and morbidity rates (3%). The long-term angiographic follow-up showed complete occlusion in 81% and near total obliteration in further 14%. All standard aneurysms with one-year-follow-up achieved complete obliteration after deployment of a single PED. Our new BD scale was revealed as an independent predictor of aneurysm occlusion in a multivariable analysis. All aneurysms with a high flow disruption grade showed complete occlusion at follow-up irrespective of PED number or aneurysm complexity. Our data suggest that treatment with the Pipeline Embolization Device should be recognized as a primary management strategy for a highly selected cohort of predominantly complex intracranial aneurysms. We further show that a priori assessment of aneurysm complexity and our new post-interventional angiographic flow disruption scale predict the occlusion probability and may help to determine the adequate number of per-aneurysm devices. Copyright © 2018 Elsevier Inc. All rights reserved.

  1. Water flow induced transport of Pseudomonas fluorescens cells through soil columns as affected by inoculant treatment

    NARCIS (Netherlands)

    Hekman, W.E.; Heijnen, C.E.; Trevors, J.T.; Elsas, van J.D.


    Water flow induced transport of Pseudomonas fluorescens cells through soil columns was measured as affected by the inoculant treatment. Bacterial cells were introduced into the topsoil of columns, either encapsulated in alginate beads of different types or mixed with bentonite clay in concentrations

  2. Treatment of intracranial aneurysms. Reconstruction of the parent artery with flow-diverting (Silk) stent

    DEFF Research Database (Denmark)

    Wagner, Aase; Cortsen, Marie; Hauerberg, John


    INTRODUCTION: Since the flow diverters (FDs) have been introduced it is possible to treat aneurysms that are considered difficult or impossible to treat with usual endovascular or surgical methods. It is still uncertain which aneurysms are suitable for this new treatment. We present the periproce...

  3. Regulation of local subcutaneous blood flow in patients with psoriasis and effects of antipsoriatic treatment on subcutaneous blood flow

    International Nuclear Information System (INIS)

    Klemp, P.


    Local regulation of the doubled subcutaneous blood flow (SBF) rates in psoriatic lesional skin was studied in 8 patients using a traumatic epicutaneous 133 Xe labeling washout technique. Venous stasis of 40 mm Hg induced a significant reduction in the SBF (-34%, p less than 0.01), i.e., a normal vasoconstrictor response. Limb elevation of 40 cm above heart level induced no statistical changes in the SBF (p = 0.50), i.e., a normal local autoregulation response. This indicates normal, local regulation mechanisms of SBF in psoriasis. In another 8 patients, the effect on SBF of a 4-week antipsoriatic treatment with tar was studied in lesional and symmetrically nonlesional skin areas. One patient was clear of psoriasis on day 22, and was followed only to that time. The mean pretreatment SBF in lesional skin areas was 3.87 +/- SD 0.78 ml X (100 g X min)-1, which was not statistically different from measurements on days 3, 7, 14, and 21 after treatment had started. Between day 21 and day 28, the SBF decreased significantly to 3.38 +/- SD 0.78 ml X (100 g X min)-1, p less than 0.05. The difference between the pretreatment SBF and SBF at the end of treatment was statistically significant, p less than 0.05. The changes in SBF in symmetrically nonlesional skin areas were statistically nonsignificant during the period of treatment. Pretreatment SBF was 2.60 +/- SD 1.08 (N = 8), and on day 28 was 1.91 +/- SD 0.74 ml X (100 g X min)-1 (N = 7). However, the tendency of a decreasing SBF at the end of treatment was a clear trend, since SBF in 6 of 7 patients decreased during the third week and in the patient who was discharged on day 22, a decrease in the SBF was observed on days 14 and 21

  4. Flow

    DEFF Research Database (Denmark)

    Knoop, Hans Henrik


    FLOW. Orden i hovedet på den fede måde Oplevelsesmæssigt er flow-tilstanden kendetegnet ved at man er fuldstændig involveret, fokuseret og koncentreret; at man oplever stor indre klarhed ved at vide hvad der skal gøres, og i hvilket omfang det lykkes; at man ved at det er muligt at løse opgaven...

  5. Changes in flow-mediated dilatation in patients with femoropopliteal occlusion receiving conservative and invasive treatment. (United States)

    Pawlaczyk, Katarzyna; Gabriel, Marcin; Urbanek, Tomasz; Dzieciuchowicz, Łukasz; Begier-Krasińska, Beata; Stanisić, Michał; Wachal, Krzysztof; Zieliński, Maciej


    Although the beneficial effect of revascularisation on reduction of local clinical ischaemic symptoms has been well established, its effect on systemic vascular endothelial function has not been fully explained yet. To determine changes in endothelium-dependent flow-mediated dilatation in patients with unilateral femoropopliteal occlusion receiving medical and surgical treatment. Seventy-nine patients with symptomatic atherosclerotic ischaemia of lower extremities, treated with endovascular procedures, with femoropopliteal graft, or receiving conservative treatment (21-day controlled treadmill training) were enrolled in the study. Ankle brachial pressure index (ABPI), skin blood flow on the feet, and flow-mediated dilatation (FMD) of brachial arteries were measured in each patient at baseline and after 90 days of follow-up. The ABPI, vasomotion in the myogenic frequency band, and FMD increased significantly in surgical patients. In patients after femoropopliteal bypass a significant increase of vasomotion in the endothelial frequency band was also observed. In patients receiving conservative treatment (treadmill training), vasomotion in the myogenic frequency band increased whereas the FMD remained unchanged. It seems that surgical treatment may contribute to reducing the risk of cardiovascular complications in patients with advanced peripheral artery disease, as a result of improving the systemic vascular endothelial function. Limiting treatment to just treadmill training increases pain-free walking distance but does not improve systemic vascular endothelial function.

  6. Computational fluid dynamics evaluation of flow reversal treatment of giant basilar tip aneurysm. (United States)

    Alnæs, Martin Sandve; Mardal, Kent-Andre; Bakke, Søren; Sorteberg, Angelika


    Therapeutic parent artery flow reversal is a treatment option for giant, partially thrombosed basilar tip aneurysms. The effectiveness of this treatment has been variable and not yet studied by applying computational fluid dynamics. Computed tomography images and blood flow velocities acquired with transcranial Doppler ultrasonography were obtained prior to and after bilateral endovascular vertebral artery occlusion for a giant basilar tip aneurysm. Patient-specific geometries and velocity waveforms were used in computational fluid dynamics simulations in order to determine the velocity and wall shear stress changes induced by treatment. Therapeutic parent artery flow reversal lead to a dramatic increase in aneurysm inflow and wall shear stress (30 to 170 Pa) resulting in an increase in intra-aneurysmal circulation. The enlargement of the circulated area within the aneurysm led to a re-normalization of the wall shear stress and the aneurysm remained stable for more than 8 years thereafter. Therapeutic parent artery flow reversal can lead to unintended, potentially harmful changes in aneurysm inflow which can be quantified and possibly predicted by applying computational fluid dynamics. © The Author(s) 2015.

  7. Effect of Fixed Orthodontic Treatment on Salivary Flow, pH and Microbial Count

    Directory of Open Access Journals (Sweden)

    Sepideh Arab


    Full Text Available Objectives: The present study was designed to evaluate the changes in saliva properties and oral microbial flora in patients undergoing fixed orthodontic treatment.Materials and Methods: Two important saliva properties namely the salivary flow rate and pH as well as oral microbial flora were assessed in 30 orthodontic patients before starting fixed orthodontic treatment and after six, 12 and 18 weeks of treatment. Selective media, Sabouraud dextrose agar, Mitis salivarius agar and Rogosa agar were used for isolation of Candida albicans, Streptococcus mutans and Lactobacillus acidophilus, respectively. Statistical analysis was performed using Friedman and Dunn’s tests. P< 0.05 was considered statistically significant.Results: After six, 12 and 18 weeks of commencing fixed orthodontic treatment, the total colony counts of Candida albicans, Streptococcus mutans and Lactobacillus acidophilus showed a significant increase. The saliva pH decreased during the orthodontic treatment (P< 0.05 while the salivary flow did not change significantly. Conclusions: Fixed orthodontic treatment causes major changes in the saliva properties. The changes in oral microflora and saliva properties show the importance of caries preventive measures during orthodontic treatment.

  8. Overland flow generation mechanisms affected by topsoil treatment: Application to soil conservation (United States)

    González Paloma, Hueso; Juan Francisco, Martinez-Murillo; Damian, Ruiz-Sinoga Jose; Hanoch, Lavee


    Hortonian overland-flow is responsible for significant amounts of soil loss in Mediterranean geomorphological systems. Restoring the native vegetation is the most effective way to control runoff and sediment yield. During the seeding and plant establishment, vegetation cover may be better sustained if soil is amended with an external source. Four amendments were applied in an experimental set of plots: straw mulching (SM); mulch with chipped branches of Aleppo Pine (Pinus halepensis L.) (PM); TerraCotten hydroabsobent polymers (HP); sewage sludge (RU); and control (C). Plots were afforested following the same spatial pattern, and amendments were mixed with the soil at the rate 10 Mg ha-1. This research demonstrates the role played by the treatments in overland flow generation mechanism (runoff, overland flow and soil moisture along the soil profile). The general overland flow characteristics showed that in the C plots the average overland flow was 8.0 ± 22.0 l per event, and the HP plots produced a similar mean value (8.1 ± 20.1 l). The average overland flow per event was significantly less for soil amended with SM, PM or RU (2.7 ± 8.3 l; 1.3 ± 3.5 l and 2.2 ± 5.9 l, respectively). There was a similar trend with respect to the maximum overland flow. The mean sediment yield per event was relatively high in the C and HP plots (8.6 ± 27.8 kg and 14.8 ± 43.4 kg, respectively), while significantly lower values were registered in the SM, PM and RU plots (0.4 ± 1.0 kg; 0.2 ± 0.3 kg and 0.2 ± 0.3 kg, respectively). Very similar trends were found for the maximum sediment yield. Regarding to the soil moisture values, there was a difference in the trends between the C and HP plots and the SM, PM and RU plots. In the C and HP plots the general trend was for a decrease in soil moisture downward through the soil profile, while in the SM, PM and RU plots the soil moisture remained relatively constant or increased, except for the RU treatment in which the soil moisture

  9. Liver volume, portal vein flow, and clearance of indocyanine green and antipyrine in hyperthyroidism before and after antithyroid treatment

    DEFF Research Database (Denmark)

    Andersen, Vibeke; Sonne, J; Court-Payen, M


    The aim of the study was to examine liver volume, portal vein flow, and indocyanine green (ICG) and antipyrine clearance in hyperthyroidism before and after antithyroid drug treatment.......The aim of the study was to examine liver volume, portal vein flow, and indocyanine green (ICG) and antipyrine clearance in hyperthyroidism before and after antithyroid drug treatment....

  10. Rate of Salivary flow and secretion of immunoglobulin A, in cancer patients subjected to radiotherapy treatment

    International Nuclear Information System (INIS)

    Mahmoud, M.S.; Iskandar, N.A.; Abd Latif, W.; Roushdy, H.M.; Ahmad, A.S.; Haggag, M.G.


    The rate of salivary flow and salivary secretion of immunoglobulin A were studied in forty human male subjects, divided into two groups : The first consists of twenty male healthy volunteers. Whereas the second consists of twenty male patients suffering from squamous cell carcinoma affecting the head and neck region without direct involvement of the major salivary glands. patients of this group received radiotherapy as the sole line of treatment where the field of gamma irradiation involved the major salivary glands. The results revealed higher rate of salivary flow and salivary IgA in the cancer patients group as compared with the control group. A progressive decrease of both salivary flow rate and IgA was observed with increasing doses of gamma irradiation. 4 figs., 2 tabs


    Energy Technology Data Exchange (ETDEWEB)

    Duignan, M.; Nash, C.; Poirier, M.


    In the interest of accelerating waste treatment processing, the DOE has funded studies to better understand filtration with the goal of improving filter fluxes in existing cross-flow equipment. The Savannah River National Laboratory (SRNL) was included in those studies, with a focus on start-up techniques, filter cake development, the application of filter aids (cake forming solid precoats), and body feeds (flux enhancing polymers). This paper discusses the progress of those filter studies. Cross-flow filtration is a key process step in many operating and planned waste treatment facilities to separate undissolved solids from supernate slurries. This separation technology generally has the advantage of self-cleaning through the action of wall shear stress created by the flow of waste slurry through the filter tubes. However, the ability of filter wall self-cleaning depends on the slurry being filtered. Many of the alkaline radioactive wastes are extremely challenging to filtration, e.g., those containing compounds of aluminum and iron, which have particles whose size and morphology reduce permeability. Unfortunately, low filter flux can be a bottleneck in waste processing facilities such as the Savannah River Modular Caustic Side Solvent Extraction Unit and the Hanford Waste Treatment Plant. Any improvement to the filtration rate would lead directly to increased throughput of the entire process. To date increased rates are generally realized by either increasing the cross-flow filter axial flowrate, limited by pump capacity, or by increasing filter surface area, limited by space and increasing the required pump load. SRNL set up both dead-end and cross-flow filter tests to better understand filter performance based on filter media structure, flow conditions, filter cleaning, and several different types of filter aids and body feeds. Using non-radioactive simulated wastes, both chemically and physically similar to the actual radioactive wastes, the authors performed

  12. Visualizing the flow of evidence in network meta-analysis and characterizing mixed treatment comparisons. (United States)

    König, Jochem; Krahn, Ulrike; Binder, Harald


    Network meta-analysis techniques allow for pooling evidence from different studies with only partially overlapping designs for getting a broader basis for decision support. The results are network-based effect estimates that take indirect evidence into account for all pairs of treatments. The results critically depend on homogeneity and consistency assumptions, which are sometimes difficult to investigate. To support such evaluation, we propose a display of the flow of evidence and introduce new measures that characterize the structure of a mixed treatment comparison. Specifically, a linear fixed effects model for network meta-analysis is considered, where the network estimates for two treatments are linear combinations of direct effect estimates comparing these or other treatments. The linear coefficients can be seen as the generalization of weights known from classical meta-analysis. We summarize properties of these coefficients and display them as a weighted directed acyclic graph, representing the flow of evidence. Furthermore, measures are introduced that quantify the direct evidence proportion, the mean path length, and the minimal parallelism of mixed treatment comparisons. The graphical display and the measures are illustrated for two published network meta-analyses. In these applications, the proposed methods are seen to render transparent the process of data pooling in mixed treatment comparisons. They can be expected to be more generally useful for guiding and facilitating the validity assessment in network meta-analysis. Copyright © 2013 John Wiley & Sons, Ltd.


    Directory of Open Access Journals (Sweden)

    D. A. Domenyuk


    Full Text Available Laser Doppler flowmetry was used to investigate the palatal muscosa capillary bloodflow in children aged 4.5-9 years with crowded teeth undergoing treatment with removable orthodontic appliances from cold-cured base polymers. The results obtained from the examination of the capillary blood flow based on the amplitude standard deviation, the variation coefficient, the amplitudes of vasomotor, breathing, and cardiorhythms, as well as the indices for active and passive mechanisms of blood flow modulation at the areas under study, showed that the hemodynamics indices in the palatal muscosa got disturbed a month after the treatment was started while the disturbances went even worse at later stages

  14. Development of substance flow based Life Cycle Assessment tool for sewage sludge treatment and disposal

    DEFF Research Database (Denmark)

    Yoshida, Hiroko; Clavreul, Julie; Scheutz, Charlotte

    Life Cycle Assessment (LCA) is a method to quantify environmental impacts of products or systems. It is often done by correlating material and energy demands with certain input characteristics. An attempt was made to evaluate the robustness of the substance flow based LCA for wastewater and sludge...... treatment processes. Operational data of a conventional wastewater treatment plant over 12 years was collected. A cluster analysis was conducted to determine the relatedness of each input and output characteristic at the whole plant level. The results indicate that the output from the wastewater and sludge...

  15. Fluctuation Analysis of Peak Expiratory Flow and Its Association with Treatment Failure in Asthma. (United States)

    Kaminsky, David A; Wang, Lucy L; Bates, Jason H T; Thamrin, Cindy; Shade, David M; Dixon, Anne E; Wise, Robert A; Peters, Stephen; Irvin, Charles G


    Temporal fluctuations have been demonstrated in lung function and asthma control, but the effect of controller therapy on these fluctuations is unknown. To determine if fluctuations in peak expiratory flow (PEF) are predictive of subsequent treatment failure and may be modified by controller therapy. We applied detrended fluctuation analysis to once-daily PEF data from 493 participants in the LOCCS (Leukotriene Modifier Corticosteroid or Corticosteroid-Salmeterol) trial of the American Lung Association Airways Clinical Research Centers. We evaluated the coefficient of variation of PEF (CVpef) and the scaling exponent α, reflecting self-similarity of PEF, in relation to treatment failure from the run-in period of open-label inhaled fluticasone, and the treatment periods for subjects randomized to (1) continued twice daily fluticasone (F), (2) once daily fluticasone plus salmeterol (F + S), or (3) once daily oral montelukast (M). The CVpef was higher in those with treatment failure in the F and F + S groups in the run-in phase, and all three groups in the treatment phase. α was similar between those with and without treatment failure in all three groups during the run-in phase but was higher among those with treatment failure in the F and F + S groups during the treatment phase. Participants in all three groups showed variable patterns of change in α leading up to treatment failure. We conclude that increased temporal self-similarity (α) of more variable lung function (CVpef) is associated with treatment failure, but the pattern of change in self-similarity leading up to treatment failure is variable across individuals.

  16. Efficiency of a Horizontal Sub-Surface Flow Constructed Wetland Treatment System in an Arid Area

    Directory of Open Access Journals (Sweden)

    Abeer Albalawneh


    Full Text Available The main objective of this study was to evaluate the performance and treatment efficiency of the Horizontal Sub-Surface Flow Constructed Wetland treatment system (HSF-CW in an arid climate. Seventeen sub-surface, horizontal-flow HSF-CW units have been operated for approximately three years to improve the quality of partially-treated municipal wastewater. The studied design parameters included two sizes of volcanic tuff media (i.e., fine or coarse, two different bed dimensions (i.e., long and short, and three plantation types (i.e., reed, kenaf, or no vegetation as a control. The effluent Biological Oxygen Demand (BOD5, Chemical Oxygen Demand (COD, Total Suspended Solid (TSS, and phosphorus from all of the treatments were significantly lower as compared to the influent and demonstrated a removal efficiency of 55%, 51%, 67%, and 55%, respectively. There were significant increases in Electrical Conductivity (EC, sulfate, and calcium in the effluent of most HSF-CWs due to evaporative concentration and mineral dissolution from the media. The study suggests that unplanted beds with either fine or coarse media are the most suitable combinations among all of the studied designs based on their treatment efficiency and less water loss in arid conditions.

  17. Evaluation of alternative flow sheets for upgrade of the Process Waste Treatment Plant

    International Nuclear Information System (INIS)

    Robinson, S.M.


    Improved chemical precipitation and/or ion-exchange (IX) methods are being developed at the Oak Ridge National Laboratory (ORNL) in an effort to reduce waste generation at the Process Waste Treatment Plant (PWTP). A wide variety of screening tests were performed on potential precipitation techniques and IX materials on a laboratory scale. Two of the more promising flow sheets have been tested on pilot and full scales. The data were modeled to determine the operating conditions and waste generation at plant-scale and used to develop potential flow sheets for use at the PWTP. Each flow sheet was evaluated using future-valve economic analysis and performance ratings (where numerical values were assigned to costs, process flexibility and simplicity, stage of development, waste reduction, environmental and occupational safety, post-processing requirements, and final waste form). The results of this study indicated that several potential flow sheets should be considered for further development, and more detailed cost estimates should be made before a final selection is made for upgrade of the PWTP. 19 refs., 52 figs., 22 tabs

  18. Industrial-scale application of the plunger flow electro-oxidation reactor in wastewater depth treatment. (United States)

    Huang, Guolong; Yao, Jiachao; Pan, Weilong; Wang, Jiade


    Effluents after biochemical treatment contain pollutants that are mostly non-degradable. Based upon previous pilot-scale test results, an industrial-scale electro-oxidation device was built to decompose these refractory materials in the effluent from a park wastewater treatment plant. The electro-oxidation device comprised a ditch-shaped plunger flow electrolysis cell, with mesh-plate Ti/PbO2 electrodes as the anode and the same size mesh-plate Ti as the cathode. Wastewater flowed vertically through electrodes; the effective volume of the cell was 2.8 m(3), and the surface-to-volume ratio was 17.14 m(2) m(-3). The optimal current density was 100 A m(-2), and a suitable flow velocity was 14.0 m h(-1). The removal efficiencies for chemical oxygen demand and color in the effluent were over 60.0 and 84.0 %, respectively. In addition, the electro-oxidation system offered a good disinfection capability. The specific energy consumption for this industrial-scale device was 43.5 kWh kg COD(-1), with a current efficiency of 32.8 %, which was superior to the pilot-scale one. To meet the requirements for emission or reuse, the operation cost was $0.44 per ton of effluent at an average price for electricity of $0.11 kWh(-1).

  19. Influence of hummocks and emergent vegetation on hydraulic performance in a surface flow wastewater treatment wetland (United States)

    Keefe, Steffanie H.; Daniels, Joan S.; Runkel, Robert L.; Wass, Roland D.; Stiles, Eric A.; Barber, Larry B.


    A series of tracer experiments were conducted biannually at the start and end of the vegetation growing season in a surface flow wastewater treatment wetland located near Phoenix, AZ. Tracer experiments were conducted prior to and following reconfiguration and replanting of a 1.2 ha treatment wetland from its original design of alternating shallow and deep zones to incorporate hummocks (shallow planting beds situated perpendicular to flow). Tracer test data were analyzed using analysis of moments and the one‐dimensional transport with inflow and storage numerical model to evaluate the effects of the seasonal vegetation growth cycle and hummocks on solute transport. Following reconfiguration, vegetation coverage was relatively small, and minor changes in spatial distribution influenced wetland hydraulics. During start‐up conditions, the wetland underwent an acclimation period characterized by small vegetation coverage and large transport cross‐sectional areas. At the start of the growing season, new growth of emergent vegetation enhanced hydraulic performance. At the end of the growing season, senescing vegetation created short‐circuiting. Wetland hydrodynamics were associated with high volumetric efficiencies and velocity heterogeneities. The hummock design resulted in breakthrough curves characterized by multiple secondary tracer peaks indicative of varied flow paths created by bottom topography.

  20. Endovascular treatment with 'kissing' flow diverter stents of two unruptured aneurysms at a fenestrated vertebrobasilar junction. (United States)

    Consoli, Arturo; Renieri, Leonardo; Nappini, Sergio; Ricciardi, Fabrizio; Grazzini, Giulia; Scarpini, Giulia; Capaccioli, Leonardo; Mangiafico, Salvatore


    Fenestration of the vertebrobasilar junction (VBJ) is a rare condition which may be associated with the presence of aneurysms. The endovascular approach is usually the first-line treatment in these cases since the location of the aneurysm may be unsuitable for a surgical approach. This anatomical variation may even influence the endovascular strategy, particularly in those cases in which the sacrifice of a vessel could be avoided. This paper describes an innovative approach of flow diversion in such challenging situations. Two women were admitted after an occasional diagnosis of an aneurysm arising from a fenestrated VBJ. In both cases the endovascular approach was performed with two flow diverter stents and dual antiplatelet therapy was administered for 6 months. Complete exclusion of the two aneurysms was obtained after 6 and 7 months, respectively, and the clinical outcome was excellent. Endovascular treatment of unruptured aneurysms located on a fenestrated VBJ with flow diverter stents represents a valid therapeutic approach with excellent clinical and radiological outcomes.

  1. Domestic wastewater treatment using multi-electrode continuous flow MFCs with a separator electrode assembly design

    KAUST Repository

    Ahn, Yongtae


    Treatment of domestic wastewater using microbial fuel cells (MFCs) will require reactors with multiple electrodes, but this presents unique challenges under continuous flow conditions due to large changes in the chemical oxygen demand (COD) concentration within the reactor. Domestic wastewater treatment was examined using a single-chamber MFC (130 mL) with multiple graphite fiber brush anodes wired together and a single air cathode (cathode specific area of 27 m2/m3). In fed-batch operation, where the COD concentration was spatially uniform in the reactor but changed over time, the maximum current density was 148 ± 8 mA/m2 (1,000 Ω), the maximum power density was 120 mW/m2, and the overall COD removal was >90 %. However, in continuous flow operation (8 h hydraulic retention time, HRT), there was a 57 % change in the COD concentration across the reactor (influent versus effluent) and the current density was only 20 ± 13 mA/m2. Two approaches were used to increase performance under continuous flow conditions. First, the anodes were separately wired to the cathode, which increased the current density to 55 ± 15 mA/m2. Second, two MFCs were hydraulically connected in series (each with half the original HRT) to avoid large changes in COD among the anodes in the same reactor. The second approach improved current density to 73 ± 13 mA/m2. These results show that current generation from wastewaters in MFCs with multiple anodes, under continuous flow conditions, can be improved using multiple reactors in series, as this minimizes changes in COD in each reactor. © 2012 Springer-Verlag Berlin Heidelberg.

  2. A comprehensive substance flow analysis of a municipal wastewater and sludge treatment plant

    DEFF Research Database (Denmark)

    Yoshida, Hiroko; Christensen, Thomas Højlund; Guildal, T.


    The fate of total organic carbon, 32 elements (Al, Ag, As, Ba, Be, Br, Ca, Cd, Cl, Co, Cr, Cu, Fe, Hg, K, Li, Mg, Mn, Mo, N, Na, Ni, P, Pb, S, Sb, Se, Sn, Sr, Ti, V, and Zn) and 4 groups of organic pollutants (linear alkylbenzene sulfonates, bis(2-ethylhexyl)phthalate, polychlorinated biphenyl...... significant substance flows. In contrast, the contribution by spent water from the flue gas treatment process was almost negligible. Screening of human and eco-toxicity by applying the consensus-based environmental impact assessment method USEtox addressing 15 inorganic constituents showed that removal...

  3. Treatment of Chlorinated Aliphatic Contamination of Groundwater by Horizontal Recirculation Wells and by Constructed Vertical Flow Wetlands

    National Research Council Canada - National Science Library

    Shelley, Michael


    ...) constructed vertical subsurface flow wetlands. Both the natural dechlorination in wetland sediments, and the engineered dechlorination in a well using zero-valent metals have major implications for the treatment of Air Force pollutants...

  4. Treatment of back flow fluids from shale gas exploration with recovery of uranium

    International Nuclear Information System (INIS)

    Gajda, D.; Zakrzewska-Koltuniewicz, G.; Abramowska, A.; Kiegiel, K.; Niescior-Borowinska, P.; Miskiewicz, A.; Olszewska, W.; Kulisa, K.; Samszynski, Z.; Drzewicz, P.; Konieczynska, M.


    Shale gas exploitation is the cause of many social protests. According to the protesters gas extraction technology threatens the environment: it consumes huge amounts of water, creates danger of poisoning drinking water, the formation of toxic wastewater, air contamination, noise, etc. Hydro-fracturing fluids could also leach radioactive isotopes e.g. uranium from the rock. The upper content of the main elements found in examined back flow fluids in Poland are the following: chlorine: 100.00 Kg/m 3 , sodium: 40.00 kg/m 3 , potassium: 0.90 kg/m 3 , lithium: 0.15 kg/m 3 , magnesium: 2.00 kg/m 3 , calcium: 20.00 kg/m 3 , strontium: 0.80 kg/m 3 and cesium: 0.06 kg/m 3 while the upper content of trace elements are the following: uranium: 3.5 g/m 3 , lanthanum: 12.4 g/m 3 , vanadium: 1.3 g/m 3 , yttrium: 1.3 g/m 3 , molybdenum: 2.0 g/m 3 and manganese: 9.7 g/m 3 . The recovery of uranium, and other valuable metals, from back flow fluids will reduce an environmental impact of hydro-fracturing process. This poster details the treatment of back flow fluids in Poland allowing rare earth elements and uranium recovery

  5. Flow Diversion versus Standard Endovascular Techniques for the Treatment of Unruptured Carotid-Ophthalmic Aneurysms. (United States)

    Di Maria, F; Pistocchi, S; Clarençon, F; Bartolini, B; Blanc, R; Biondi, A; Redjem, H; Chiras, J; Sourour, N; Piotin, M


    Over the past few years, flow diversion has been increasingly adopted for the treatment of intracranial aneurysms, especially in the paraclinoid and paraophthalmic carotid segment. We compared clinical and angiographic outcomes and complication rates in 2 groups of patients with unruptured carotid-ophthalmic aneurysms treated for 7 years by either standard coil-based techniques or flow diversion. From February 2006 to December 2013, 162 unruptured carotid-ophthalmic aneurysms were treated endovascularly in 138 patients. Sixty-seven aneurysms were treated by coil-based techniques in 61 patients. Flow diverters were deployed in 95 unruptured aneurysms (77 patients), with additional coiling in 27 patients. Complication rates, clinical outcome, and immediate and long-term angiographic results were retrospectively analyzed. No procedure-related deaths occurred. Four procedure-related thromboembolic events (6.6%) leading to permanent morbidity in 1 case (1.6%) occurred in the coiling group. Neurologic complications were observed in 6 patients (7.8%) in the flow-diversion group, resulting in 3.9% permanent morbidity. No statistically significant difference was found between complication (P = .9) and morbidity rates (P = .6). In the coiling group (median follow-up, 31.5 ± 24.5 months), recanalization occurred at 1 year in 23/50 (54%) aneurysms and 27/55 aneurysms (50.9%) at the latest follow-up, leading to retreatment in 6 patients (9%). In the flow-diversion group (mean follow-up, 13.5 ± 10.8 months), 85.3% (35/41) of all aneurysms were occluded after 12 months, and 74.6% (50/67) on latest follow-up. The retreatment rate was 2.1%. Occlusion rates between the 2 groups differed significantly at 12 months (P < .001) and at the latest follow-up (P < .005). Our retrospective analysis shows better long-term occlusion of carotid-ophthalmic aneurysms after use of flow diverters compared with standard coil-based techniques, without significant differences in permanent morbidity

  6. Endovascular treatment of unruptured aneurysms of cavernous and ophthalmic segment of internal carotid artery with flow diverter device Pipeline

    Directory of Open Access Journals (Sweden)

    Jevsek Marko


    Full Text Available Intra-arterial treatment of aneurysms by redirecting blood flow is a newer method. The redirection is based on a significantly more densely braided wire stent. The stent wall keeps the blood in the lumen of the stent and slows down the turbulent flow in the aneurysms. Stagnation of blood in the aneurysm sac leads to the formation of thrombus and subsequent exclusion of the aneurysm from the circulation. The aim of the study was to evaluate flow diverter device Pipeline for broad neck and giant aneurysm treatment.

  7. Reduced serotonin synthesis and regional cerebral blood flow after anxiolytic treatment of social anxiety disorder. (United States)

    Frick, Andreas; Åhs, Fredrik; Appel, Lieuwe; Jonasson, My; Wahlstedt, Kurt; Bani, Massimo; Merlo Pich, Emilio; Bettica, Paolo; Långström, Bengt; Lubberink, Mark; Fredrikson, Mats; Furmark, Tomas


    Social anxiety disorder (SAD) is associated with increased fear-related neural activity in the amygdala and we recently found enhanced serotonin synthesis rate in the same region. Anxiolytic agents like selective serotonin re-uptake inhibitors (SSRIs) and neurokinin-1 receptor (NK1R) antagonists reduce amygdala activity and may attenuate serotonin formation according to animal studies. Here, we examined the effects of SSRI pharmacotherapy, NK1R antagonism, and placebo on serotonin synthesis rate in relation to neural activity, measured as regional cerebral blood flow (rCBF), and symptom improvement in SAD. Eighteen SAD patients were randomized to receive daily double-blind treatment for six weeks either with the SSRI citalopram (n=6; 40mg), the NK1R antagonist GR205171 (n=6; 5mg; 4 weeks following 2 weeks of placebo), or placebo (n=6). Serotonin synthesis rate at rest and rCBF during stressful public speaking were assessed, before and after treatment, using positron emission tomography with the tracers [ 11 C]5-hydroxytryptophan and [ 15 O]water respectively. The Liebowitz Social Anxiety Scale (LSAS-SR) indexed symptom severity. All groups exhibited attenuated amygdala serotonin synthesis rate after treatment, which was associated with reduced amygdala rCBF during public speaking and accompanied by symptom improvement. These results are consistent with the notion that serotonin in the amygdala exerts an anxiogenic influence and, conversely, that anxiolysis is achieved through decreased serotonin formation in the amygdala. Copyright © 2016 Elsevier B.V. and ECNP. All rights reserved.

  8. Corrosion in Supercritical carbon Dioxide: Materials, Environmental Purity, Surface Treatments, and Flow Issues

    Energy Technology Data Exchange (ETDEWEB)

    Sridharan, Kumar; Anderson, Mark


    separately to high purity CO{sub 2}. Task 3: Evaluation of surface treatments on the corrosion performance of alloys in supercritical CO{sub 2}: Surface treatments can be very beneficial in improving corrosion resistance. Shot peening and yttrium and aluminum surface treatments will be investigated. Shot peening refines the surface grain sizes and promotes protective Cr-oxide layer formation. Both yttrium and aluminum form highly stable oxide layers (Y{sub 2}O{sub 3} and Al{sub 2}O{sub 3}), which can get incorporated in the growing Fe-oxide layer to form an impervious complex oxide to enhance corrosion resistance. Task 4: Study of flow-assisted corrosion of select alloys in supercritical CO{sub 2} under a selected set of test conditions: To study the effects of flow-assisted corrosion, tests will be conducted in a supercritical CO{sub 2} flow loop. An existing facility used for supercritical water flow studies at the proposing university will be modified for use in this task. The system is capable of flow velocities up to 10 m/s and can operate at temperatures and pressures of up to 650°C and 20 MPa, respectively. All above tasks will be performed in conjunction with detailed materials characterization and analysis using scanning electron microscopy/energy dispersive spectroscopy (SEM-EDS), x-ray diffraction (XRD), Auger electron spectroscopy (AES) techniques, and weight change measurements. Inlet and outlet gas compositions will be monitored using gas chromatography-mass spectrometry (GCMS).

  9. Effect of design and operational conditions on the performance of subsurface flow treatment wetlands: Emerging organic contaminants as indicators. (United States)

    Kahl, Stefanie; Nivala, Jaime; van Afferden, Manfred; Müller, Roland A; Reemtsma, Thorsten


    Six pilot-scale subsurface flow treatment wetlands loaded with primary treated municipal wastewater were monitored over one year for classical wastewater parameters and a set of emerging organic compounds (EOCs) serving as process indicators for biodegradation: caffeine, ibuprofen, naproxen, benzotriazole, diclofenac, acesulfame, and carbamazepine. The wetland technologies investigated included conventional horizontal flow, unsaturated vertical flow (single and two-stage), horizontal flow with aeration, vertical flow with aeration, and reciprocating. Treatment efficiency for classical wastewater parameters and EOCs generally increased with increasing design complexity and dissolved oxygen concentrations. The two aerated wetlands and the two-stage vertical flow system showed the highest EOC removal, and the best performance in warm season and most robust performance in the cold season. These three systems performed better than the adjacent conventional WWTP with respect to EOC removal. Acesulfame was observed to be removed (>90%) by intensified wetland systems and with use of a tertiary treatment sand filter during the warm season. Elevated temperature and high oxygen content (aerobic conditions) proved beneficial for EOC removal. For EOCs of moderate to low biodegradability, the co-occurrence of aerobic conditions and low content of readily available carbon appears essential for efficient removal. Such conditions occurred in the aerated systems and with use of a tertiary treatment sand filter. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Techniques of material-flow-specific residual waste treatment; Techniken der stoffstromspezifischen Restabfallbehandlung

    Energy Technology Data Exchange (ETDEWEB)

    Maak, D.; Collins, H.J. [Technische Univ. Braunschweig, Leichtweiss - Inst. fuer Wasserbau (Germany)


    The success achieved with large-scale plants for mechanical-biological residual waste treatment has led to a change of course in waste pretreatment. In view of the low emissions via the water and gas routes from landfilled wastes and the low costs of waste treatment some authorising authorities have meanwhile issued special licences pursuant to clause no. 2.4 of the Technical Code on Household Waste, thus enabling mechanical-biological residual waste treatment plants to continue operations beyond the year 2005. Beside offering a means of treatment and disposal, cost-effective mechanical-biological pretreatment also provides an opportunity for going over to material-flow-specific residual waste treatment. These process stages permit recirculating valuable materials and using other materials for energy production. They can be retrofitted on a modular basis in existing plants. If these advantages of the present innovative pretreatment methods are not used, then mechanical-biological pretreatment can still serve as a preparatory stage for thermal treatment. To date there has been no practical experience with this innovative method of residual waste treatment. However, industrial-scale trials have shown that each individual treatment stage is capable of being carried out successfully. [Deutsch] Die guten Erfolge im grosstechnischen Betrieb von Anlagen zur mechanisch-biologischen Restabfallbehandlung haben zu einer Kursaenderung bei der Vorbehandlung von Abfaellen gefuehrt. Geringe Emissionen der deponierten Abfaelle auf dem Gas- und Wasserpfad sowie geringe Kosten fuer die Behandlung der Abfaelle haben dazu gefuehrt, dass inzwischen bereits einige Genehmigungsbehoerden eine Ausnahmegenehmigung nach Nr. 2.4 der TA Siedlungsabfall erteilt haben und damit der Betrieb von mechanisch-biologischen Restabfallbehandlungsanlagen auch nach 2005 ermoeglicht wird. Neben der alleinigen Behandlung und Deponierung bietet die kostenguenstige Vorbehandlung mit mechanisch

  11. Treatment of ruptured complex and large/giant ruptured cerebral aneurysms by acute coiling followed by staged flow diversion. (United States)

    Brinjikji, Waleed; Piano, Mariangela; Fang, Shanna; Pero, Guglielmo; Kallmes, David F; Quilici, Luca; Valvassori, Luca; Lozupone, Emilio; Cloft, Harry J; Boccardi, Edoardo; Lanzino, Giuseppe


    OBJECT Flow-diversion treatment has been shown to be associated with high rates of angiographic obliteration; however, the treatment is relatively contraindicated in the acute phase following subarachnoid hemorrhage (SAH) as these patients require periprocedural dual antiplatelet therapy. Acute coiling followed by flow diversion has emerged as an intriguing and feasible treatment option for ruptured complex and giant aneurysms. In this study the authors report outcomes and complications of patients with ruptured aneurysms undergoing coiling in the acute phase followed by planned delayed flow diversion. METHODS This case series includes patients from 2 institutions. All patients underwent standard endovascular coiling in the acute phase after SAH with the intention and plan to proceed with flow diversion at a later date. Outcomes studied included angiographic occlusion, procedure-related complications, and long-term clinical outcome as measured using the modified Rankin Scale. RESULTS A total of 31 patients underwent coiling in the acute phase with the intention to undergo flow diversion at a later date. The mean aneurysm size was 15.8 ± 7.9 mm. Of the 31 patients undergoing coiling, 4 patients could not undergo further flow-diverter therapy: 3 patients (9.7%) died of complications of subarachnoid hemorrhage and 1 patient had permanent morbidity as a result of perioperative ischemic stroke (3.1%). Twenty-seven patients underwent staged placement of flow diverters after adequate recovery. The median time to treatment was 16 weeks. There was one case of aneurysm rebleeding following coil treatment. There were no cases of permanent morbidity or mortality resulting from flow-diverter treatment. Twenty-four patients underwent imaging follow-up; 18 of these patients had aneurysms that were completely or nearly completely occluded (58.1% on an intent-to-treat basis). At last follow-up (mean 18.3 months), 25 patients had mRS scores ≤ 2 (80.6% on an intent-to-treat basis

  12. Thermal treatment of starch slurry in Couette-Taylor flow apparatus

    Directory of Open Access Journals (Sweden)

    Hubacz Robert


    Full Text Available In this paper, thermal processing of starch slurry in a Couette-Taylor flow (CTF apparatus was investigated. Gelatinized starch dispersion, after treatment in the CTF apparatus, was characterized using such parameters like starch granule diameters (or average diameter, starch granule swelling degree (quantifying the amount of water absorbed by starch granules and concentration of dissolved starch. These parameters were affected mostly by the process temperature, although the impact of the axial flow or rotor rotation on them was also observed. Moreover, the analysis of results showed a relatively good correlation between these parameters, as well as, between those parameter and apparent viscosity of gelatinized starch dispersion. Meanwhile, the increase in the value of the apparent viscosity and in shear-tinning behaviour of dispersion was associated with the progress of starch processing in the CTF apparatus. Finally, the CTF apparatuses of different geometries were compared using numerical simulation of the process. The results of the simulation indicated that the apparatus scaling-up without increasing the width of the gap between cylinders results in higher mechanical energy consumption per unit of processed starch slurry.

  13. A numerical treatment of geodynamic viscous flow problems involving the advection of material interfaces (United States)

    Lenardic, A.; Kaula, W. M.


    Effective numerical treatment of multicomponent viscous flow problems involving the advection of sharp interfaces between materials of differing physical properties requires correction techniques to prevent spurious diffusion and dispersion. We develop a particular algorithm, based on modern shock-capture techniques, employing a two-step nonlinear method. The first step involves the global application of a high-order upwind scheme to a hyperbolic advection equation used to model the distribution of distinct material components in a flow field. The second step is corrective and involves the application of a global filter designed to remove dispersion errors that result from the advection of discontinuities (e.g., material interfaces) by high-order, minimally dissipative schemes. The filter introduces no additional diffusion error. Nonuniform viscosity across a material interface is allowed for by the implementation of a compositionally weighted-inverse interface viscosity scheme. The combined method approaches the optimal accuracy of modern shock-capture techniques with a minimal increase in computational time and memory. A key advantage of this method is its simplicity to incorporate into preexisting codes be they finite difference, element, or volume of two or three dimensions.

  14. Long term high flow heated oxygen treatment in COPD – lung function and physical ability

    DEFF Research Database (Denmark)

    Weinreich, Ulla; Storgaard, Line; Hockey, Hans


    Introduction: Long term oxygen therapy (LTOT) improves survival in patients with COPD with resting hypoxemia. Despite this, a progressive loss of lung function and physical ability is expected in COPD. The AIRVO device delivers nasal high flow (NHF) warmed and humidified oxygen-enriched air, 20-3...... of AIRVO-NHF preventing decrease in FEV1, increasing 6MWT and mMRC score (in particular) in COPD patients in need of LTOT.......Introduction: Long term oxygen therapy (LTOT) improves survival in patients with COPD with resting hypoxemia. Despite this, a progressive loss of lung function and physical ability is expected in COPD. The AIRVO device delivers nasal high flow (NHF) warmed and humidified oxygen-enriched air, 20......-30 L/minute via the Optiflow interface to COPD patients in need of LTOT.Aim: To investigate the treatment effect of NHF on lung function, (Forced Expiratory Volume in 1 second (FEV1) and Forced Vital Capacity (FVC) in liters and percent, 6 minute walking test (6MWT) and modified MRC (mMRC) dyspnoea...

  15. Monitoring of Legionella pneumophila viability after chlorine dioxide treatment using flow cytometry. (United States)

    Mustapha, Pascale; Epalle, Thibaut; Allegra, Séverine; Girardot, Françoise; Garraud, Olivier; Riffard, Serge


    The viability of three Legionella pneumophila strains was monitored after chlorine dioxide (ClO2) treatment using a flow cytometric assay. Suspensions of L. pneumophila cells were submitted to increasing concentrations of ClO2. Culturable cells were still detected when using 4 mg/L, but could no longer be detected after exposure to 6 mg/L of ClO2, although viable but not culturable (VBNC) cells were found after exposure to 4-5 mg/L of ClO2. When testing whether these VBNC were infective, two of the strains were resuscitated after co-culture with Acanthamoeba polyphaga, but neither of them could infect macrophage-like cells. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  16. Dual flow diversion stents for aneurysm treatment in a partial unfused basilar artery. (United States)

    Gontu, Vamsi; Bhogal, Pervinder; Brouwer, Patricius A


    Unfused basilar arteries, frequently but erroneously referred to as 'fenestrations', are not uncommonly associated with aneurysms. The difficulty in treating these aneurysms lie in the fact that they are often wide necked and frequently incorporate both channels of the unfused segment, with varying calibres of the channels, necessitating technically challenging treatment strategies. It is important to preserve both channels because of the potential presence of perforating arteries originating from these segments. There are numerous case reports of such aneurysms being treated by coils alone, coiling with balloon assistance and stent-assisted coiling in configurations such as 'X', 'double barrel' or waffle cone. We present an exemplary case, in which an aneurysm on a partial unfused basilar segment was treated with parallel flow diverters with an excellent result on follow-up imaging. © The Author(s) 2015.

  17. Numerical Treatment of Two-phase Flow in Porous Media Including Specific Interfacial Area

    KAUST Repository

    El-Amin, Mohamed


    In this work, we present a numerical treatment for the model of two-phase flow in porous media including specific interfacial area. For numerical discretization we use the cell-centered finite difference (CCFD) method based on the shifting-matrices method which can reduce the time-consuming operations. A new iterative implicit algorithm has been developed to solve the problem under consideration. All advection and advection-like terms that appear in saturation equation and interfacial area equation are treated using upwind schemes. Selected simulation results such as pc–Sw–awn surface, capillary pressure, saturation and specific interfacial area with various values of model parameters have been introduced. The simulation results show a good agreement with those in the literature using either pore network modeling or Darcy scale modeling.

  18. Multilayer flow modulator stent technology: a treatment revolution for US patients? (United States)

    Sultan, Sherif; Hynes, Niamh


    Thoracoabdominal aortic repair is a high-risk procedure in most experienced centers, not only because of anatomical complexity but also due to the fragility of the patients in whom these aneurysms occur. Such repairs are complex, time-consuming and impose a systemic injury upon the patients, regardless of whether the repair is performed by open surgery or via a fenestrated/branched technique. The substantive risks associated with such repairs include death, dialysis and paralysis. The multilayer flow modulator (MFM) is a disruptive technology which promises a minimally invasive reproducible treatment option, with clinical results demonstrating physiological modulation of the aortic sac with abolition of spinal injury. The mode of action of MFM forces us to completely rethink aneurysm pathogenesis and, consequently, it has been met with much cynicism. We aim to uncloak some of the mystery surrounding the MFM, clarify its mode of action and explore the truth behind its clinical effectiveness.

  19. Cerebral blood flow and end-tidal PCO2 during prolonged acetazolamide treatment in humans

    DEFF Research Database (Denmark)

    Friberg, L; Kastrup, J; Rizzi, Dominick Albert


    decreasing alveolar PCO2 to 70% of the control value at the end of the treatment period. In healthy humans the hyperventilation will not increase brain oxygenation significantly at sea level. But at high altitudes the enhanced ventilatory drive will improve oxygenation of the brain, and this may account......One oral dose of 1,000 mg of acetazolamide caused an acute 38% increase in cerebral blood flow (CBF) in eight healthy volunteers. During the following 10 days the subjects took 1,000 mg acetazolamide daily. CBF normalized within the first 2 days. The drug induced mild hyperventilation, gradually...... of a transient extracellular acidosis dilating brain arterioles, whereas increased ventilatory drive results from a gradually increasing mild intracellular acidosis in the brain....

  20. Long-term nasal high flow treatment with oxygen in COPD - exacerbations, admissions and mortality

    DEFF Research Database (Denmark)

    Weinreich, Ulla; Storgaard, Line; Hockey, Hans


    Introduction: Long term oxygen therapy (LTOT) improves survival in patients with COPD with resting hypoxemia. Exacerbations (AECOPD) and hospital admissions are prevalent and have a negative impact on prognosis. The AIRVO device delivers nasal high flow (NHF) heated, humidified oxygenated air, 20......-30 L/min, to COPD patients in need of LTOT.Aim: To investigate the number of self-reported AECOPD, AECOPD-related hospitalizations and all-cause mortality in LTOT COPD patients treated with AIRVO-NHF.Method: In this prospective, randomized, controlled, one-year study, 200 COPD patients treated...... with LTOT, were randomized to AIRVO-NHF (n=100) or usual care (n=100). Where possible, patients who ceased use of the AIRVO device were still followed. For count data, Poisson regression models were used and Cox’s proportional hazards model for all-cause mortality.Results: The two treatment groups were...

  1. Influence of Mold Surface Treatments on Flow of Polymer in Injection Moulding. Application to Weldlines (United States)

    Chailly, M.; Charmeau, J.-Y.; Bereaux, Y.; Monasse, B.


    Due to increasing expectations from the market, the aspect of molded parts has to be improved constantly. Some of the defects observed on these parts such as weldlines are related to the filling stage. To limit this, we investigated the influence on weldlines using various surface deposits on the mold surface, mainly PVD and PACVD deposits : Chromium nitride (CrN), Titanium nitride (TiN), Diamond like Carbon (DLC), Chromium and polished steel (PG) on an instrumented plate mold. Injection campaign was led on three polymers which differ in terms of nature (amorphous, semi-crystalline, copolymers). We studied the evolution of the dimensions of weldlines appearing on the plate using the same injection parameters for a given polymer, but with various deposits and thicknesses. Another aspect that had been investigated is the morphology of the weldline through the thickness of the part, depending on polymer nature. Adhesion of polymer at the flow front with the mold surface proved to change. The modification of the initial contact in the filling stage and thus the thermal resistance at the mold implied a change in the process, increasing or reducing the pressure loss in the flow and differential shrinkage in the final part. The induced impact on dimensions of the weldlines allowed to distinguish which surface treatments were able to reduce the defect. A complementary study was led on both polymers in molten state and deposits in terms of wetting using a sessile drop method to confirm the adhesion at the polymer/mold interface. This study proved the influence of the use of surface treatments has clearly an impact on the filling stage of the injection molding process, and it is necessary to get a better knowledge of the interactions between physical adhesion, tribology of polymer/mold contact, and thermal properties of the coatings and their impact on solidification of the polymer.

  2. Numerical simulation of the debris flow dynamics with an upwind scheme and specific friction treatment (United States)

    Sánchez Burillo, Guillermo; Beguería, Santiago; Latorre, Borja; Burguete, Javier


    means of the Nash-Shutcliffe statistic [10]. This error estimation can be used to calibrate the input friction coefficients, providing an efficient tool for risk analysis in many regions of the world and specially in areas with steep topographic gradients such as mountain ranges, heavily incised river networks, coastal cliffs, etc. References: [1] H. J. Koerner, "Reichweite und geschwindigkeit von bergstürzen und fleisschneelawinen". Rock Mechanics, 8, 225-256 (1976) [2] P. J. McLellan and P. K. Kaiser, "Application of a two-parameter model to rock avalanches in the mackenzine mountains". 4th International Symposium on Landslides, 135-140 (1984). [3] A. Kent and O. Hungr, "Runout characteristics of debris from dump failures in mountainous terrain: stage 2: analysis, modelling and prediction". British Columbia Mine Waste Rock Pile Research Committee and CANMET (1995). [4] O. Hungr and S. G. Evans, "Rock avalanche runout prediction using a dynamic model". 7th International Symposium on Landslides, 233-238 (1996). [5] D. Rickenmann and T. Koch, "Comparison of debris flow modelling approaches". First International Conference on Debris-Flow Hazards Mitigation: Mechanics, Prediction, and Assessment. ASCE, ed. New York. C.L. Chen (1997). [6] P. Bertolo and G. F. Wieczorek, "Calibration of numerical models for small debris flows in Yosemite Valley, California, USA". Natural Hazards in Earth System Sciences (5) 993-1001 (2005). [7] S. Beguería and Th. J. van Asch and J. P. Malet and S. Gröndahl, "A GIS-based numerical model for simulating the kinematics of mud and debris flows over complex terrain". Natural Hazards in Earth System Sciences (9) 1897-1909 (2009). [8] G. Sánchez Burillo, S. Beguería, B. Latorre and J. Burguete, "Numerical treatment of the friction term in upwind schemes in debris flow runout modelling". ASCE Journal of Hydraulic Engineering (sent for publication). [9] A. Voellmy, Über die Zerstörungskraft von Lawinen. Schweizer. Bauzeitung (1955). [10] J. E

  3. Decreased Symptoms without Augmented Skin Blood Flow in Subjects with RLS/WED after Vibration Treatment. (United States)

    Mitchell, Ulrike H; Hilton, Sterling C; Hunsaker, Erik; Ulfberg, Jan


    Vascular disturbances leading to tissue hypoxia have been named as a possible cause for RLS/WED. Vibration to the whole body (WBV) in subjects with RLS/WED results in increased skin blood flow (SBF). The aims of this investigation were to (1) determine if a two-week treatment with WBV will decrease symptoms associated with RLS/WED and, (2) if so, determine if the mechanism for improvement in symptoms is related to an increase in SBF, as measured in flux. Eleven subjects with RLS/WED underwent 2 weeks of 14-minute intermittent WBV and a 2-week sham treatment in randomized order. Pre and post intervention RLS symptom severity were compared. Baseline SBF was compared between subjects with RLS/WED and an age- and sex-matched control group. A crossover design (aim 1) and a matched case-control design and repeated measures design (aim 2) were used. The data analyses consisted of 2-sample and paired t-tests; where applicable we used a standard crossover design adjustment. WBV did significantly decrease symptoms associated with RLS/WED compared to baseline data and compared to sham treatment. The baseline flux was significantly lower in RLS/WED subjects than matched controls, but this deficit was negated with WBV. There was no increase in resting SBF over the 2 weeks of treatment. Subjects with RLS/WED have decreased SBF but are able to increase flux to the same level as normal subjects with WBV. A 2-week intervention with WBV decreases symptoms associated with RLS/WED, but this does not seem to be related to an increase in resting SBF. © 2016 American Academy of Sleep Medicine.

  4. Endovascular treatment of unruptured aneurysms of cavernous and ophthalmic segment of internal carotid artery with flow diverter device Pipeline. (United States)

    Jevsek, Marko; Mounayer, Charbel; Seruga, Tomaz


    Intra-arterial treatment of aneurysms by redirecting blood flow is a newer method. The redirection is based on a significantly more densely braided wire stent. The stent wall keeps the blood in the lumen of the stent and slows down the turbulent flow in the aneurysms. Stagnation of blood in the aneurysm sac leads to the formation of thrombus and subsequent exclusion of the aneurysm from the circulation. The aim of the study was to evaluate flow diverter device Pipeline for broad neck and giant aneurysm treatment. Fifteen patients with discovered aneurysm of the internal carotid artery were treated between November 2010 and February 2014. The majority of aneurysms of the internal carotid artery were located intradural at the ophthalmic part of the artery. The patients were treated using a flow diverter device Pipeline, which was placed over the aneurysm neck. Treatment success was assessed clinically and angiographically using O'Kelly Marotta scale. Control angiography immediately after the release of the stent showed stagnation of the blood flow in the aneurysm sac. In none of the patients procedural and periprocedural complications were observed. 6 months after the procedure, control CT or MR angiography showed in almost all cases exclusion of the aneurysm from the circulation and normal blood flow in the treated artery. Neurological status six months after the procedure was normal in all patients. Treatment of aneurysms with flow diverter Pipeline device is a safe and significantly less time consuming method in comparison with standard techniques. This new method is a promising approach in treatment of broad neck aneurysms.

  5. A new treatment of capillarity to improve the stability of IMPES two-phase flow formulation

    KAUST Repository

    Kou, Jisheng


    In this paper, we present an efficient numerical method for two-phase immiscible flow in porous media with different capillarity pressures. In highly heterogeneous permeable media, the saturation is discontinuous due to different capillary pressure functions. One popular scheme is to split the system into a pressure and a saturation equation, and to apply IMplicit Pressure Explicit Saturation (IMPES) approach for time stepping. One disadvantage of IMPES is instability resulting from the explicit treatment for capillary pressure. To improve stability, the capillary pressure is usually incorporated in the saturation equation which gradients of saturation appear. This approach, however, does not apply to the case of different capillary pressure functions for multiple rock-types, because of the discontinuity of saturation across rock interfaces. In this paper, we present a new treatment of capillary pressure, which appears implicitly in the pressure equation. Using an approximation of capillary function, we substitute the implicit saturation equation into the pressure equation. The coupled pressure equation will be solved implicitly and followed by the explicit saturation equation. Five numerical examples are provided to demonstrate the advantages of our approach. Comparison shows that our proposed method is more efficient and stable than the classical IMPES approach. © 2010 Elsevier Ltd.

  6. Electrochemical treatment of Procion Black 5B using cylindrical flow reactor--a pilot plant study. (United States)

    Raghu, S; Basha, C Ahmed


    The paper presents the results of an efficient electrochemical treatment of Procion Black 5B--a pilot plant study. Experiments were conducted at different current densities and selected electrolyte medium using Ti/RuO2 as anode, stainless-steel as cathode in a cylindrical flow reactor. By cyclic voltammetric analysis, the best condition for maximum redox reaction rate was found to be in NaCl medium. During the various stages of electrolysis, parameters such as COD, colour, FTIR, UV-vis spectra studies, energy consumption and mass transfer coefficient were computed and presented. The experimental results showed that the electrochemical oxidation process could effectively remove colour and the chemical oxygen demand (COD) from the synthetic dye effluent. The maximum COD reduction and colour removal efficiencies were 74.05% and 100%, respectively. Probable theory, reaction mechanism and modeling were proposed for the oxidation of dye effluent. The results obtained reveal the feasibilities of application of electrochemical treatment for the degradation of Procion Black 5B.

  7. Assessment of activated sludge, membrane bioreactors and vertical flow wetlands for upgrading sewage treatment works. (United States)

    Besançon, A; Le Corre, K S; Dotro, G; Jefferson, B


    This paper demonstrates that utilising a vertical flow (VF) wetland after a conventional activated sludge (CAS) delivers equivalent or better effluent quality to a membrane bioreactor (MBR) based on a side-by-side pilot trial. The CAS was operated under the solids retention times (SRT) of 6, 12, and 20 days, with the effluent from each pilot plant fed onto a soil aquifer treatment column to better understand their water reuse application potential. Results showed an upgraded CAS + VF system could deliver effluents with median values of 34 mgO 2 .L -1 , 7 mg.L -1 and 1.9 mg.L -1 for organics, solids and ammonia nitrogen, respectively, which were statistically similar to those from the MBR. Water reuse standards were achieved by the upgraded system for most parameters, with the exception of total coliform removal. The upgraded system delivered superior metal removal when compared to the CAS. An economic analysis showed upgrading a CAS with a VF wetland was more favourable than investing in an MBR system for example works of 5000 and 50,000 population equivalents if the VF system was operated at hydraulic loading rates of 0.03 m.d -1 and 0.08 m.d -1 , respectively. This was delivered for a tenth of the carbon footprint of the MBR treatment.

  8. Swine wastewater treatment using vertical subsurface flow constructed wetland planted with Napier grass

    Directory of Open Access Journals (Sweden)

    Pantip Klomjek


    Full Text Available This research aims to investigate the pollutant removal efficiencies in swine wastewater using a vertical subsurface flow constructed wetland (VSF CW planted with two species of Napier grass. The grass productivities were also cultivated and compared in order to provide information for species selection. Twelve treatment units were set up with the VSF CWs planted with Giant Napier grass (Pennisetum purpureum cv. King grass and Dwarf Napier grass (Pennisetum purpureum cv. Mott. with 2 and 5 cm d−1 of hydraulic loading rates (HLR. Comparisons of removal efficiency and grass productivity were analyzed using Duncan's Multiple Range Test and t-test at the significant level 0.05. Both species of Napier grass performed more than 70% of removal efficiency of BOD and TKN. The VSF CW planted with Giant Napier grass at 5 cm d−1 HLR performed the highest BOD removal efficiency of 94 ± 1%, while the 2 cm d−1 HLR removed COD with efficiency of 64 ± 6%. The results also showed the effluent from all treatment units contained averages of BOD, COD, TSS, TKN and pH that followed Thailand's swine wastewater quality standard. Average fresh yields and dry yields were between 4.6 ± 0.4 to 15.2 ± 1.2 and 0.5 ± 0.1 to 2.2 ± 0.1 kg m−2, respectively. The dry yields obtained from four cutting cycles in five months of CW system operation were higher than the ones planted with a traditional method, but declined continuously after each cutting cycle. Both species of Napier grass indicated their suitability to be used in the VSF CW for swine wastewater treatment.

  9. Volume changes of extremely large and giant intracranial aneurysms after treatment with flow diverter stents

    Energy Technology Data Exchange (ETDEWEB)

    Carneiro, Angelo; Byrne, James V. [ohn Radcliffe Hospital, Oxford Neurovascular and Neuroradiology Research Unit, Nuffield Department of Surgical Sciences, Oxford (United Kingdom); Rane, Neil; Kueker, Wilhelm; Cellerini, Martino; Corkill, Rufus [John Radcliffe Hospital, Department of Neuroradiology, Oxford (United Kingdom)


    This study assessed volume changes of unruptured large and giant aneurysms (greatest diameter >20 mm) after treatment with flow diverter (FD) stents. Clinical audit of the cases treated in a single institution, over a 5-year period. Demographic and clinical data were retrospectively collected from the hospital records. Aneurysm volumes were measured by manual outlining at sequential slices using computerised tomography (CT) or magnetic resonance (MR) angiography data. The audit included eight patients (seven females) with eight aneurysms. Four aneurysms involved the cavernous segment of the internal carotid artery (ICA), three the supraclinoid ICA and one the basilar artery. Seven patients presented with signs and symptoms of mass effect and one with seizures. All but one aneurysm was treated with a single FD stent; six aneurysms were also coiled (either before or simultaneously with FD placement). Minimum follow-up time was 6 months (mean 20 months). At follow-up, three aneurysms decreased in size, three were unchanged and two increased. Both aneurysms that increased in size showed persistent endosaccular flow at follow-up MR; in one case, failure was attributed to suboptimal position of the stent; in the other case, it was attributed to persistence of a side branch originating from the aneurysm (similar to the endoleak phenomenon of aortic aneurysms). At follow-up, five aneurysms were completely occluded; none of these increased in volume. Complete occlusion of the aneurysms leads, in most cases, to its shrinkage. In cases of late aneurysm growth or regrowth, consideration should be given to possible endoleak as the cause. (orig.)

  10. Treatment of intracranial aneurysms by flow diverter devices: Long-term results from a single center

    Energy Technology Data Exchange (ETDEWEB)

    Briganti, Francesco, E-mail: [Unit of Interventional Neuroradiology, Department of Advanced Biomedical Sciences, “Federico II” University, Via S.Pansini 5., 80131 Naples (Italy); Napoli, Manuela, E-mail: [Department of Advanced Biomedical Sciences, “Federico II” University, Via S.Pansini 5., 80131 Naples (Italy); Leone, Giuseppe, E-mail: [Department of Advanced Biomedical Sciences, “Federico II” University, Via S.Pansini 5., 80131 Naples (Italy); Marseglia, Mariano, E-mail: [Department of Advanced Biomedical Sciences, “Federico II” University, Via S.Pansini 5., 80131 Naples (Italy); Mariniello, Giuseppe, E-mail: [Division of Neurosurgery, Department of Neurosciences, Reproductive and Odontostomatological Sciences, “Federico II” University, Via S.Pansini 5., 80131 Naples (Italy); Caranci, Ferdinando, E-mail: [Department of Advanced Biomedical Sciences, “Federico II” University, Via S.Pansini 5., 80131 Naples (Italy); Tortora, Fabio, E-mail: [Chair of Neuroradiology, “Magrassi Lanzara” Clinical-Surgical Department, Second University of Naples, Viale Colli Aminei 21, 80131 Naples (Italy); Maiuri, Francesco, E-mail: [Division of Neurosurgery, Department of Neurosciences, Reproductive and Odontostomatological Sciences, “Federico II” University, Via S.Pansini 5., 80131 Naples (Italy)


    Highlights: • We report the long-term results (2–4 years) with Flow Diverter Devices (FDD) from a single-center. • We recommend the use of FDD for large-neck aneurysms of the ICA syphon. • We think that more sophisticate FDD will reduce the incidence of technical adverse events. - Abstract: Objectives: Flow-Diverter Devices (FDD) are a new generation stents designed for the treatment of the intracranial aneurysms. This article reports the long-term results (2–4 years) of this treatment from a single-center. Methods: From November 2008 to January 2012, 35 patients (29 females and 6 males; mean age 53.9 y) with 39 intracranial aneurysms were treated by FDD. Five patients (14.3%) had ruptured aneurysms and 30 (85.7%) had no previous hemorrhage. The procedures were performed in 5 patients (14.3%) with SILK and in 30 (85.7%) with PED. In 3 patients FDDs were used as a second treatment after failure of previous coiling (2 cases) or stenting (one case). The 39 aneurysms were in supraclinoid ICA in 26 (66.7%), cavernous ICA in 2 (5.1%), PCoA in 4 (10.2%), MCA in 5 (12.9%), SCA in 1 (2.6%) and PICA in 1 (2.6%). The aneurysms were small (<10 mm) in 32 cases (82%), large (11–25 mm) in 6 (15.3%) and giant in 1 (2.6%). The occlusion rate according to the aneurysm location, size and neck and the complications were evaluated. Results: Peri-procedural complications included transient dysarthria (2 patients), vasospasm with acute intra-stent aggregation (one), microwire rupture (one) and failure of the stent opening (one). The follow-up was made between 24 and 62 months (mean 41 months); clinical examination and CTA were performed at 1, 3, 6 and 12 months after the procedure. The complete occlusion was confirmed by CTA and DSA. MRI with angiographic-studies was taken every year. Complete occlusion was obtained in 35 aneurysms (92.1%) and subtotal in 3 (7.9%). Complete occlusion occurred at 3 months in 24 cases (68.6%), within 3 and 6 months in 9 (25.7%). The rate and

  11. The consequences of air flow on the distribution of aqueous species during dielectric barrier discharge treatment of thin water layers (United States)

    Tian, Wei; Lietz, Amanda M.; Kushner, Mark J.


    The desired outcomes of wet tissue treatment by dielectric barrier discharges (DBDs) strongly depend on the integrated fluences of reactive species incident onto the tissue, which are determined by power, frequency and treatment time. The reactivity produced by such plasmas is often expected to be proportional to treatment time due to the accumulation of radicals in the liquid over the tissue. However, one of the typically uncontrolled parameters in DBD treatment of liquids and tissue is gas flow, which could affect the delivery of plasma produced radicals to the tissue. Gas flow can redistribute long-lived, plasma produced gas phase species prior to solvating in the liquid, while not greatly affecting the solvation of short-lived species. Gas flow can therefore potentially be a control mechanism for tailoring the fluences of reactive species to the tissue. In this paper, we report on a computational investigation of the consequences of gas flow on treatment of liquid layers covering tissue by atmospheric DBDs by up to 100 pulses. We found that gas flow (through residence time of the gas) can control the production of gas phase species requiring many collisions to form, such as reactive nitrogen species (RNS). The resulting solvation of the RNS in turn controls the production of aqueous species such as \\text{NO}\\text{3aq}- and \\text{ONOO}\\text{aq}- (aq denotes an aqueous species). With the exception of O3 and O3aq, reactive oxygen species (ROS) are less sensitive to gas flow, and so OHaq and H2O2aq, are determined primarily by discharge properties.

  12. Oxygen flux implications of observed nitrogen removal rates in subsurface-flow treatment wetlands. (United States)

    Tanner, C C; Kadlec, R H


    Nitrification, an oxygen-requiring microbial process, is generally considered the rate-limiting step for N removal in subsurface-flow constructed wetlands treating organic wastewaters. We used a simplified model of sequential N transformations and sinks to infer required rates of oxygen supply at 5 stages along experimental wetland mesocosms supplied with four different organic wastewaters with contrasting ratios of COD: N and forms of N. Mass balances of water-borne organic, ammoniacal and nitrate N, and plant and sediment N uptake showed average net rates of N mineralisation ranging from 0.22-0.53 g m(-2) d(-1), nitrification 0.56-2.15 g m(-2) d(-1), denitrification 0.47-1.99 g m(-2) d(-1) (60-84% of measured N removal) and plant assimilation 0.28-0.47 g m(-2) d(-1). The nitrogenous oxygen demand (NOD) required to support the observed nitrification rates alone was high compared to expected fluxes from surficial and plant-mediated oxygen transfer. In the presence of high levels of degradable organic matter (COD removal rates up to 66 g m(-2) d(-1)), heterotrophs with significantly higher oxygen affinities and energy yields are expected to outcompete nitrifiers for available oxygen. Problems with commonly held assumptions on the nature of coupled nitrification-denitrification in treatment wetlands are discussed.

  13. Ibuprofen removal in horizontal subsurface flow constructed wetlands: treatment performance and fungal community dynamics. (United States)

    Zhang, Dongqing; Luo, Jinxue; Lee, Zarraz May Ping; Gersberg, Richard M; Liu, Yu; Tan, Soon Keat; Ng, Wun Jern


    The treatment performance of ibuprofen (IBP)-enriched wastewater by horizontal subsurface flow constructed wetlands planted with cattail (Typha angustifolia) and unplanted control mesocosms was investigated. Removal efficiencies of IBP were significantly (p fungal community in these wetland systems. The overall diversity of the fungal community was reduced under the IBP exposure. Taxonomic analysis revealed that 62.2% of the fungal sequences were affiliated with Basidiomycota, followed by Ascomycota (37.4%) at the phylum level. Uncultured fungus (48.2%), Chaetomium sp. (14.2%), Aspergillus sp. (12.4%), Trichoderma sp. (5.7%), Cladosporium sp. (5.4%), and Emericellopsis sp. (5.2%) were identified as dominant genera. At the genus level, a distinct profile of the fungal community in the IBP-enriched mesocosms was observed as compared to the control beds, and as well specific fungal genera were enhanced in the planted beds, regardless of IBP enrichment. However, despite these differences, the composition of the fungal community (as measured by Bray-Curtis similarity) was mostly unaffected by the significant IBP enrichment. On the other hand, a consistent similarity pattern of fungal community structure in the planted mesocosms suggests that the presence of higher macrophytes in the wetland systems may well help shape the fungal community structure.

  14. Long term high flow humidified oxygen treatment in COPD – effect on blood gases

    DEFF Research Database (Denmark)

    Storgaard, Line; Weinreich, Ulla; Hockey, Hans


    .Aim: To investigate the treatment effect on arterial blood gases (PaO2, PaCO2 and SaO2) in patients with resting hypoxemia over 12 months.Method: In this prospective, randomized controlled, one-year study, 200 COPD patients treated with LTOT, all GOLD class 4, were randomized to NHF (n=100) or usual care (n=100......Introduction: Long term oxygen therapy (LTOT) improves survival in patients with COPD with resting hypoxemia. The AIRVO device delivering nasal high flow (NHF) warmed and humidified oxygen-enriched air to COPD patients in need of LTOT. Short term studies suggest that this may reduce PaCO2 in COPD.......05 kPa for AIRVO-NHF and 0.40 kPa for control patients.Conclusion: These results show a significant difference in change of PaCO2 of 0.35 kPA more for control than for the AIRVO-NHF group of COPD patients needing LTOT....

  15. Presynaptic Dopamine Synthesis Capacity in Schizophrenia and Striatal Blood Flow Change During Antipsychotic Treatment and Medication-Free Conditions. (United States)

    Eisenberg, Daniel Paul; Yankowitz, Lisa; Ianni, Angela M; Rubinstein, Dani Y; Kohn, Philip D; Hegarty, Catherine E; Gregory, Michael D; Apud, José A; Berman, Karen F


    Standard-of-care biological treatment of schizophrenia remains dependent upon antipsychotic medications, which demonstrate D 2 receptor affinity and elicit variable, partial clinical responses via neural mechanisms that are not entirely understood. In the striatum, where D 2 receptors are abundant, antipsychotic medications may affect neural function in studies of animals, healthy volunteers, and patients, yet the relevance of this to pharmacotherapeutic actions remains unresolved. In this same brain region, some individuals with schizophrenia may demonstrate phenotypes consistent with exaggerated dopaminergic signaling, including alterations in dopamine synthesis capacity; however, the hypothesis that dopamine system characteristics underlie variance in medication-induced regional blood flow changes has not been directly tested. We therefore studied a cohort of 30 individuals with schizophrenia using longitudinal, multi-session [ 15 O]-water and [ 18 F]-FDOPA positron emission tomography to determine striatal blood flow during active atypical antipsychotic medication treatment and after at least 3 weeks of placebo treatment, along with presynaptic dopamine synthesis capacity (ie, DOPA decarboxylase activity). Regional striatal blood flow was significantly higher during active treatment than during the placebo condition. Furthermore, medication-related increases in ventral striatal blood flow were associated with more robust amelioration of excited factor symptoms during active medication and with higher dopamine synthesis capacity. These data indicate that atypical medications enact measureable physiological alterations in limbic striatal circuitry that vary as a function of dopaminergic tone and may have relevance to aspects of therapeutic responses.

  16. [On "knowing routine regularities and making flexible management" in midnight-noon ebb-flow aided acupuncture treatment]. (United States)

    Su, Xu-Lin


    The old theory of midnight-noon ebb-flow for selection of acupoints in acupuncture treatment of clinical disorders is mechanical in the calculation of the time (hours and days) of flowing and ebbing of qi and blood in terms of the heavenly stems and earthly branches, thus, it has been called considerable questions by many Chinese physicians in different historical periods. The author of the present paper holds that the time calculation is merely a method, only the symptom-differentiation and innovation ideas are the key points for the acupuncture treatment. Following summarizing up the key points of this acupuncture management, the present paper thinks that on-time and time-point selection, acupoint-open and acupoint-closing, academic schools and clinical choice-making are critical for clinical practice. It denotes that despite the midnight-noon ebb-flow acupuncture management has its special calculation method, but the calculation always differs from person to person, from time to time, and from place to place, and the best treatment is conducted according to syndrome-differentiation. Thus, when applying the midnight-noon ebb-flow acupuncture method, we should not adhere to mechanical calculation, and rather, thoroughly understand the conventional management regularities and make corresponding changes in the treatment of different clinical conditions, i.e., inherit the predecessors' excellent academic thoughts on one hand, and conduct innovation research and application on the basis of current natural and social environments on the other hand.

  17. Flow-diverting stents allow efficient treatment of unruptured, intradural dissecting aneurysms of the vertebral artery: An explanatory approach using in vivo flow analysis. (United States)

    Gölitz, Philipp; Struffert, Tobias; Hoelter, Philip; Eyüpoglu, Ilker; Knossalla, Frauke; Doerfler, Arnd


    Our study aimed to evaluate the efficiency of flow-diverting stents (FDS) in treating unruptured, intradural dissecting aneurysms of the vertebral artery (VADAs). Additionally, the effect of FDS on the aneurysmal flow pattern was investigated by performing in vivo flow analysis using parametric color coding (PCC). We evaluated 11 patients with unruptured, intradural VADAs, treated with FDS. Pre- and postinterventional DSA-series were postprocessed by PCC, and time-density curves were calculated. The parameters aneurysmal inflow-velocity, outflow-velocity and relative time-to-peak (rTTP) were calculated. Pre- and postinterventional values were compared and correlated with the occlusion rate after six months. Follow-up DSA detected 10 aneurysms occluded, meaning an occlusion rate of 91%. No procedure-related morbidity and mortality was found. Flow analyses revealed a significant reduction of aneurysmal inflow- velocity and prolongation of rTTP after FDS deployment. Concerning aneurysm occlusion, the postinterventional outflow-velocity turned out to be a marginally statistically significant predictor. A definite threshold value (-0.7 density change/s) could be determined for the outflow-velocity that allows prediction of complete aneurysm occlusion with high sensitivity and specificity (100%). Using FDS can be considered an efficient and safe therapy option in treating unruptured, intradural VADA. From in vivo flow analyses the postinterventional aneurysmal outflow-velocity turned out to be a potential predictor for later complete aneurysm occlusion. Here, it might be possible to determine a threshold value that allows prediction of aneurysm occlusion with high specificity and sensitivity. As fast, applicable and easy-to-handle tool, PCC could be used for procedural monitoring and might contribute to further treatment optimization. © The Author(s) 2015.

  18. Modelling hydrodynamics of horizontal flow steel slag filters designed to upgrade phosphorus removal in small wastewater treatment plants. (United States)

    Barca, Cristian; Roche, Nicolas; Troesch, Stéphane; Andrès, Yves; Chazarenc, Florent


    Steel slag filters, if well designed and operated, may upgrade phosphorus removal in small wastewater treatment plants such as stabilization ponds and constructed wetlands. The main objective of this study was to develop a systemic modelling approach to describe changes in the hydraulic performances and internal hydrodynamics of steel slag filters under real dynamic operating conditions. The experimental retention time distribution curves (RTD curves) determined from tracer experiments performed at different times during the first year of operation of two field-scale steel slag filters were analyzed through a three stage process. First, a statistical analysis of the RTD curves was performed to determine statistical parameters of the retention time distribution. Second, classical tanks in series (TIS) and plug flow with dispersion (PFD) models were used to obtain a first evaluation of the dispersion and mixing regime. Finally, a multi-flow path TIS model, based on the assumption of several flow paths with different hydraulic properties, is proposed to accurately describe the internal hydrodynamics. Overall, the results of this study indicate that higher CaO content, round shape, and larger grain size distribution of steel slag may promote plug-like flow rather than dispersion. The results of the multi-flow path TIS model suggest that the internal hydrodynamics of steel slag filters can be primarily described by two main flow paths: (i) a faster main flow path showing higher plug flow, followed by (ii) a slower secondary flow path showing higher dispersion. The results also showed that internal hydrodynamics may change over time as a consequence of physical-chemical phenomena occurring in the filter, including accumulation of precipitates, slag hydration and carbonation, and particle segregation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. [High flow nasal cannula oxygen therapy in the treatment of acute bronchiolitis in neonates]. (United States)

    Bermúdez Barrezueta, Lorena; García Carbonell, Nuria; López Montes, Jorge; Gómez Zafra, Rafael; Marín Reina, Purificación; Herrmannova, Jana; Casero Soriano, Javier


    To determine whether the availability of heated humidified high-flow nasal cannula (HFNC) therapy was associated with a decrease in need for mechanical ventilation in neonates hospitalised with acute bronchiolitis. A combined retrospective and prospective (ambispective) cohort study was performed in a type II-B Neonatal Unit, including hospitalised neonates with acute bronchiolitis after the introduction of HFNC (HFNC-period; October 2011-April 2015). They were compared with a historical cohort prior to the availability of this technique (pre-HFNC; January 2008-May 2011). The need for mechanical ventilation between the two study groups was analysed. Clinical parameters and technique-related complications were evaluated in neonates treated with HFNC. A total of 112 neonates were included, 56 after the introduction of HFNC and 56 from the period before the introduction of HFNC. None of patients in the HFNC-period required intubation, compared with 3.6% of the patients in the pre-HFNC group. The availability of HFNC resulted in a significant decrease in the need for non-invasive mechanical ventilation (30.4% vs 10.7%; P=.01), with a relative risk (RR) of .353 (95% CI; .150-.829), an absolute risk reduction (ARR) of 19.6% (95% CI; 5.13 - 34.2), yielding a NNT of 5. In the HFNC-period, 22 patients received high flow therapy, and 22.7% (95% CI; 7.8 to 45.4) required non-invasive ventilation. Treatment with HFNC was associated with a significant decrease in heart rate (P=.03), respiratory rate (P=.01), and an improvement in the Wood-Downes Férres score (P=.00). No adverse effects were observed. The availability of HFNC reduces the need for non-invasive mechanical ventilation, allowing a safe and effective medical management of neonates with acute bronchiolitis. Copyright © 2015 Asociación Española de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

  20. Effectiveness of treatment with donepezil hydrochloride and changes in regional cerebral blood flow in patients with Alzheimer's disease

    International Nuclear Information System (INIS)

    Yoshida, Tsunetaka; Ha-Kawa, S.; Yoshimura, Masafumi; Nobuhara, Kenji; Kinoshita, Toshihiko; Sawada, Satoshi


    The objective of this study was to elucidate the relationship between the effects of donepezil hydrochloride (donepezil) and cerebral blood flow, and to evaluate the usefulness of cerebral blood flow imaging in assessing and predicting treatment effectiveness. The subjects were 29 outpatients (12 men and 17 women; age 50-82 years; mean age 69.2 years), who had received a diagnosis of Alzheimer's disease (AD). Efficacy was evaluated before donepezil administration; after 1 month, 3 months, and 6 months of drug administration; and at 1 year after completion of administration using the Japanese version of the Alzheimer's disease assessment scale-cognitive subscale (ADAS-cog), as a measure of cognitive function. The ADAS-cog has been frequently used to evaluate cognitive function in AD patients. Patients whose ADAS-cog scores improved by 3 or more points during the observation period were classified as responders, and those with no improvement were classified as nonresponders. 123 I-iofetamine (IMP) was used for single photon emission computed tomography cerebral blood flow scintigraphy. On the basis of ADAS-cog score improvement, 22 of the 29 patients were responders (7 men and 15 women; age 50-82 years; mean age 69.0 years) and seven were nonresponders (5 men and 2 women; age 61-80 years; mean age 70.0 years). The results indicate that a difference in cerebral blood flow responsiveness after 1 month of treatment distinguishes responders from nonresponders. After 1 month, blood flow was significantly decreased in all regions of nonresponders, whereas significant increases in blood flow were seen in the anterior frontal lobe and parietal lobe of responders. At that time point, blood flow in the basal ganglion differed significantly between the two groups, indicating that this difference in responsiveness after 1 month of treatment may distinguish responders from nonresponders. In cognitive function testing, the group that exhibited a complete response showed

  1. Evaluation of oscillation-free fluid-porous interface treatments for segregated finite volume flow solvers

    NARCIS (Netherlands)

    Staniç, M.; Nordlund, M.; Frederix, E.M.A.; Kuczaj, Arkadiusz K.; Geurts, Bernardus J.


    The volume-averaged approach to simulate flow in porous media is often used because of its practicality and computational efficiency. Derivation of the volume-averaged porous flow equations introduces additional porous resistance terms to the momentum equation. These porous resistance terms create

  2. A physical five-equation model for compressible two-fluid flow, and its numerical treatment

    NARCIS (Netherlands)

    J.J. Kreeft (Jasper); B. Koren (Barry)


    htmlabstractA novel five-equation model for inviscid, non-heat-conducting, compressible two-fluid flow is derived, together with an appropriate numerical method. The model uses flow equations based on conservation laws and exchange laws only. The two fluids exchange momentum and energy, for which

  3. Treatment of artificial wastewater containing two azo textile dyes by vertical-flow constructed wetlands. (United States)

    Hussein, Amjad; Scholz, Miklas


    The release of untreated dye textile wastewater into receiving streams is unacceptable not only for aesthetic reasons and its negative impacts on aquatic life but also because numerous dyes are toxic and carcinogenic to humans. Strategies, as of now, used for treating textile wastewaters have technical and economical restrictions. The greater part of the physico-chemical methods, which are used to treat this kind of wastewater, are costly, produce large amounts of sludge and are wasteful concerning some soluble dyes. In contrast, biological treatments such as constructed wetlands are cheaper than the traditional methods, environmental friendly and do not produce large amounts of sludge. Synthetic wastewater containing Acid Blue 113 (AB113) and Basic Red 46 (BR46) has been added to laboratory-scale vertical-flow construction wetland systems, which have been planted with Phragmites australis (Cav.) Trin. ex Steud. (common reed). The concentrations 7 and 208 mg/l were applied for each dye at the hydraulic contact times of 48 and 96 h. Concerning the low concentrations of BR46 and AB113, the unplanted wetlands are associated with significant (ρ wetlands concerning the removal of dyes. For the high concentrations of AB113, BR46 and a mixture of both of them, wetlands with long contact times were significantly (ρ wetlands that had short contact times in terms of dye, colour and chemical oxygen demand reductions. Regarding nitrate nitrogen (NO 3 -N), the reduction percentage rates of AB113, BR46 and a mixture dye of both of them were between 85 and 100%. For low and high inflow dye concentrations, best removals were generally recorded for spring and summer, respectively.

  4. Impact of Acute Changes in CPAP Flow Route in Sleep Apnea Treatment. (United States)

    Andrade, Rafaela G S; Madeiro, Fernanda; Piccin, Vivien S; Moriya, Henrique T; Schorr, Fabiola; Sardinha, Priscila S; Gregório, Marcelo G; Genta, Pedro R; Lorenzi-Filho, Geraldo


    CPAP is the gold standard treatment for OSA and was conceived to be applied through a nasal interface. This study was designed to determine the acute effects of changing the nasal CPAP route to oronasal and oral in upper airway patency during sleep in patients with OSA. We hypothesized that the oronasal route may compromise CPAP's effectiveness in treating OSA. Eighteen patients (mean ± SD age, 44 ± 9 years; BMI, 33.8 ± 4.7 kg/m 2 ; apnea-hypopnea index, 49.0 ± 39.1 events/hour) slept with a customized oronasal mask with nasal and oral sealed compartments connected to a multidirectional valve. Sleep was monitored by using full polysomnography and induced by low doses of midazolam. Nasal CPAP was titrated up to holding pressure. Flow route was acutely changed to the oronasal (n = 18) and oral route (n = 16) during sleep. Retroglossal area was continuously observed by using nasoendoscopy. Nasal CPAP (14.8 ± 4.1 cm H 2 O) was able to stabilize breathing in all patients. In contrast, CPAP delivered by the oronasal and oral routes promoted obstructive events in 12 (66.7%) and 14 (87.5%) patients, respectively. Compared with stable breathing during the nasal route, there was a significant and progressive reduction in the distance between the epiglottis and tongue base and the retroglossal area when CPAP was delivered by the oronasal and oral routes. CPAP delivered through the oronasal route may compromise CPAP's effectiveness in treating OSA. Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  5. Impact of Wet-Weather Peak Flow Blending on Disinfection and Treatment: A Case Study at Three Wastewater Treatment Plants (United States)

    This research project was administered by the EPA Office of Research and Development and funded by Office of Water; Office of Policy, Economics and Innovation; and Office of Research and Development. Blending is the practice of diverting a part of peak wet-weather flows at wa...

  6. Performance of down-flow hanging sponge (DHS) reactor coupled with up-flow anaerobic sludge blanket (UASB) reactor for treatment of onion dehydration wastewater. (United States)

    El-Kamah, Hala; Mahmoud, Mohamed; Tawfik, Ahmed


    In this study, a promising system consisting of up-flow anaerobic sludge blanket (UASB) reactor followed by down-flow hanging sponge (DHS) reactor was investigated for onion dehydration wastewater treatment. Laboratory experiments were conducted at two different phases, i.e., phase (1) at overall hydraulic retention time (HRT) of 11h (UASB reactor: 6h and DHS reactor: 5h) and phase (2) at overall HRT of 9.4h (UASB reactor: 5.2h and DHS reactor: 4.2h). Long-term operation results of the proposed system showed that its overall TCOD, TBOD, TSS, TKN and NH(4)-N removal efficiencies were 92 ± 5, 95 ± 2, 95 ± 2, 72 ± 6 and 99 ± 1.3%, respectively (phase 1). Corresponding values for the 2nd phase were 85.4 ± 5, 86 ± 3, 87 ± 6, 65 ± 8 and 95 ± 2.8%. Based on the available results, the proposed system could be more viable option for treatment of wastewater generated from onion dehydration industry in regions with tropical or sub-tropical climates and with stringent discharge standards. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Test of single degree of freedom acoustic treatment impedance models for multimodal acoustic propagation in duct with flow. (United States)

    Baccouche, Ryan; Moreau, Soléne; Ben Tahar, Mabrouk


    Passive acoustic treatments, also called liners, are the main solution to noise problems. The Single Degree Of Freedom (SDOF) acoustic treatment, composed of a thin material (perforated plate) affixed to air cavities with a rigid bottom, constitutes a solution. Predicting sound level reduction by an SDOF treatment requires reliable acoustic impedance models. An experimental/numerical method has been developed for a duct with an acoustic treatment to test acoustic impedance models of SDOF treatment with a multimodal propagation in the presence of a mean flow. This method is based on the comparison of experimental results from an aeroacoustic bench composed of a circular duct with a treated area, and numerical results from an FEM-PML axisymmetric model based on Galbrun's equation. The numerical results are confronted with experimental results to test impedance models up to M 0 =±0.25.

  8. Effect of average flow and capacity utilization on effluent water quality from US municipal wastewater treatment facilities. (United States)

    Weirich, Scott R; Silverstein, Joann; Rajagopalan, Balaji


    There is increasing interest in decentralization of wastewater collection and treatment systems. However, there have been no systematic studies of the performance of small treatment facilities compared with larger plants. A statistical analysis of 4 years of discharge monthly report (DMR) data from 210 operating wastewater treatment facilities was conducted to determine the effect of average flow rate and capacity utilization on effluent biochemical oxygen demand (BOD), total suspended solids (TSS), ammonia, and fecal coliforms relative to permitted values. Relationships were quantified using generalized linear models (GLMs). Small facilities (40 m³/d) had violation rates greater than 10 times that of the largest facilities (400,000 m³/d) for BOD, TSS, and ammonia. For facilities with average flows less than 40,000 m³/d, increasing capacity utilization was correlated with increased effluent levels of BOD and TSS. Larger facilities tended to operate at flows closer to their design capacity while maintaining treatment suggesting greater efficiency. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Sugarcane molasses-based bio-ethanol wastewater treatment by two-phase multi-staged up-flow anaerobic sludge blanket (UASB) combination with up-flow UASB and down-flow hanging sponge. (United States)

    Choeisai, P; Jitkam, N; Silapanoraset, K; Yubolsai, C; Yoochatchaval, W; Yamaguchi, T; Onodera, T; Syutsubo, K


    This study was designed to evaluate a treatment system for high strength wastewater (vinasse) from a sugarcane molasses-based bio-ethanol plant in Thailand. A laboratory-scale two-phase treatment system composed of a sulfate reducing (SR) tank and multi-staged up-flow anaerobic sludge blanket (MS-UASB) reactor was used as the pre-treatment unit. Conventional UASB and down-flow hanging sponge (DHS) reactors were used as the post-treatment unit. The treatment system was operated for 300 days under ambient temperature conditions (24.6-29.6 °C). The hydraulic retention time (HRT) in each unit was kept at 25 h for the two-phase system and 23 h for the UASB&DHS. The influent concentration was allowed to reach up to 15,000 mg chemical oxygen demand (COD)/L. COD removal efficiency (based on influent COD) of the two-phase MS-UASB and the UASB&DHS was 54.9 and 18.7%, respectively. Due to the effective removal of sulfide in the SR tank, the MS-UASB achieved a high methane conversion ratio of up to 97%. In DHS, nitrification occurred at the outside portion of the sponge media while denitrification occurred at the inside. Consequently, 27% of the total nitrogen (TN) was removed. An amount of 32% of residual nitrogen (28 mgN/L) was in the form of nitrate, a better nitrogen state for fertilizer.

  10. Influence of recirculation in a lab-scale vertical flow constructed wetland on the treatment efficiency of landfill leachate. (United States)

    Lavrova, Silviya; Koumanova, Bogdana


    Landfill leachate taken from a landfill situated in the north-western region of Bulgaria has been treated in a laboratory scale vertical flow constructed wetland (VF-CW) at different flow rates (40, 60 and 82 ml min(-1)) and recirculation ratios (time of water running through wetland to time of quiet water - 1:1; 1:2; 1:3). Young Phragmites australis was planted on the top layer of the reactor. The low flow rate (40 ml min(-1)) and recirculation ratio of 1:3 allowed removal efficiencies of 96% for COD (in 8 days), 92% for BOD(5) (in 3 days), 100% for ammonia (in 5 days) and 100% for total phosphorus (in 2 days). At the highest flow rate studied (82 ml min(-1)) and shorter quiet period (recirculation ratio 1:1) the water needs longer period of treatment (2 days more according to COD). The results of this study indicate that both flow rate and recirculation ratio should be taken into account for proper design of VF-CW. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  11. Delayed Treatment with Sodium Hydrosulfide Improves Regional Blood Flow and Alleviates Cecal Ligation and Puncture (CLP)-Induced Septic Shock. (United States)

    Ahmad, Akbar; Druzhyna, Nadiya; Szabo, Csaba


    Cecal ligation and puncture (CLP)-induced sepsis is a serious medical condition, caused by a severe systemic infection resulting in a systemic inflammatory response. Recent studies have suggested the therapeutic potential of donors of hydrogen sulfide (H2S), a novel endogenous gasotransmitter and biological mediator in various diseases. The aim of the present study was to assess the effect of H2S supplementation in sepsis, with special reference to its effect on the modulation of regional blood flow. We infused sodium hydrosulfide (NaHS), a compound that produces H2S in aqueous solution (1, 3, or 10 mg/kg/h, for 1 h at each dose level) in control rats or rats 24 h after CLP, and measured blood flow using fluorescent microspheres. In normal control animals, NaHS induced a characteristic redistribution of blood flow, and reduced cardiac, hepatic, and renal blood flow in a dose-dependent fashion. In contrast, in rats subjected to CLP, cardiac, hepatic, and renal blood flow was significantly reduced; infusion of NaHS (1 mg/kg/h and 3 mg/kg/h) significantly increased organ blood flow. In other words, the effect of H2S on regional blood flow is dependent on the status of the animals (i.e., a decrease in blood flow in normal controls, but an increase in blood flow in CLP). We have also evaluated the effect of delayed treatment with NaHS on organ dysfunction and the inflammatory response by treating the animals with NaHS (3 mg/kg) intraperitoneally (i.p.) at 24 h after the start of the CLP procedure; plasma levels of various cytokines and tissue indicators of inflammatory cell infiltration and oxidative stress were measured 6 h later. After 24 h of CLP, glomerular function was significantly impaired, as evidenced by markedly increased (over 4-fold over baseline) blood urea nitrogen and creatinine levels; this increase was also significantly reduced by treatment with NaHS. NaHS also attenuated the CLP-induced increases in malondialdehyde levels (an index of

  12. Early experience in the treatment of intra-cranial aneurysms by endovascular flow diversion: a multicentre prospective study.

    Directory of Open Access Journals (Sweden)

    James V Byrne

    Full Text Available INTRODUCTION: Flow diversion is a new approach to the endovascular treatment of intracranial aneurysms which uses a high density mesh stent to induce sac thrombosis. These devices have been designed for the treatment of complex shaped and large size aneurysms. So far published safety and efficacy data on this approach is sparse. MATERIAL AND METHODS: Over 8 months, standardized clinical and angiographic data were collected on 70 patients treated with a flow diverter device (SILK flow diverter (SFD in 18 centres worldwide. Treatment and early follow up details were audited centrally. SFDs were deployed alone in 57 (81% or with endosaccular coils in 10 (14% aneurysms, which included: 44 (63% saccular, 26 (37% fusiform shapes and 18 (26% small, 37 (53% large, 15 (21% giant sizes. Treatment outcome data up to 30 days were reported for all patients, with clinical (50 patients and imaging (49 patients follow up (median 119 days data available. RESULTS: Difficulties in SFD deployment were reported in 15 (21% and parent artery thrombosis in 8 (11% procedures. Procedural complications caused stroke in 1 and serious extracranial bleeding in 3 patients; 2 of whom developed fatal pneumonias. Delayed worsening of symptoms occurred in 5 patients (3 transient, 1 permanent neurological deficit, and 1 death and fatal aneurysm bleeding in 1 patient. Overall permanent morbidity rates were 2 (4% and mortality 4 (8%. Statistical analysis revealed no significant association between complications and variables related to treated aneurysm morphology or rupture status. CONCLUSION: This series is the largest reporting outcome of the new treatment approach and provides data for future study design. Procedural difficulties in SFD deployment were frequent and anti-thrombosis prophylaxis appears to reduce the resulting clinical sequelae, but at the cost of morbidity due to extracranial bleeding. Delayed morbidity appears to be a consequence of the new approach and warrants

  13. Chemical characterization of milk after treatment with thermal (HTST and UHT) and nonthermal (turbulent flow ultraviolet) processing technologies. (United States)

    Cappozzo, Jack C; Koutchma, Tatiana; Barnes, Gail


    As a result of growing interest to nonthermal processing of milk, the purpose of this study was to characterize the chemical changes in raw milk composition after exposure to a new nonthermal turbulent flow UV process, conventional thermal pasteurization process (high-temperature, short-time; HTST), and their combinations, and compare those changes with commercially UHT-treated milk. Raw milk was exposed to UV light in turbulent flow at a flow rate of 4,000L/h and applied doses of 1,045 and 2,090 J/L, HTST pasteurization, and HTST in combination with UV (before or after the UV). Unprocessed raw milk, HTST-treated milk, and UHT-treated milk were the control to the milk processed with the continuous turbulent flow UV treatment. The chemical characterization included component analysis and fatty acid composition (with emphasis on conjugated linoleic acid) and analysis for vitamin D and A and volatile components. Lipid oxidation, which is an indicator to oxidative rancidity, was evaluated by free fatty acid analysis, and the volatile components (extracted organic fraction) by gas chromatography-mass spectrometry to obtain mass spectral profile. These analyses were done over a 14-d period (initially after treatment and at 7 and 14 d) because of the extended shelf-life requirement for milk. The effect of UV light on proteins (i.e., casein or lactalbumin) was evaluated qualitatively by sodium dodecyl sulfate-PAGE. The milk or liquid soluble fraction was analyzed by sodium dodecyl sulfate-PAGE for changes in the protein profile. From this study, it appears that continuous turbulent flow UV processing, whether used as a single process or in combination with HTST did not cause any statistically significant chemical changes when compared with raw milk with regard to the proximate analysis (total fat, protein, moisture, or ash), the fatty acid profile, lipid oxidation with respect to volatile analysis, or protein profile. A 56% loss of vitamin D and a 95% loss of vitamin A

  14. The effects of poststroke captopril and losartan treatment on cerebral blood flow autoregulation in SHRsp with hemorrhagic stroke (United States)

    Smeda, John S; Daneshtalab, Noriko


    The ability of captopril and losartan treatment to restore cerebral blood flow (CBF) autoregulation after intracerebral hemorrhagic stroke (HS) was assessed in Kyoto–Wistar stroke-prone hypertensive rats (SHRsp). Laser Doppler techniques assessed CBF autoregulation in the middle cerebral artery (MCA) perfusion domain and a pressure myograph was used to measure pressure-dependent constriction (PDC) in isolated MCAs before and after stroke and after 13, 33, and 63 days of poststroke captopril or losartan treatment. The treatments did not lower blood pressure (BP) and equally suppressed plasma aldosterone after HS. The HS development was associated with the loss of CBF autoregulation, high CBF, increased CBF conductance to elevations in BP, and the loss of PDC in the MCAs. Both treatments restored these functions to prestroke levels within 13 days. The PDC and CBF autoregulation subsequently deteriorated after 63 days of captopril treatment while being maintained at prestroke levels over all durations of losartan treatment. The SHRsp subjected to 35 days of poststroke losartan treatment exhibited less blood–brain barrier (BBB) disruption and brain herniation than captopril-treated SHRsp. The superior ability of losartan to restore CBF autoregulation and myogenic function may have contributed to the more effective attenuation of cerebral damage after HS. PMID:20648036

  15. Analysis of up-flow aerated biological activated carbon filter technology in drinking water treatment. (United States)

    Lu, Shaoming; Liu, Jincui; Li, Shaowen; Biney, Elizabeth


    Problems have been found in the traditional post-positioned down-flow biological activated carbon filter (DBACF), such as microorganism leakage and low biodegradability. A pilot test was carried out to place a BACF between the sediment tank and the sand filter; a new technology of dual media up-flow aerated biological activated carbon filter (UBACF) was developed. Results showed that in terms of the new process, the up-flow mode was better than the down-flow. Compared with the DBACF, the problem of microorganism leakage could be well resolved with the UBACF process by adding disinfectant before the sand filtration, and a similar adsorption effect could be obtained. For the tested raw water, the COD(Mn) and NH3-N removal rate was 54.6% and 85.0%, respectively, similar to the waterworks with the DBACF process. The UBACF greatly enhanced oxygen supply capability and mass transfer rate via aeration, and the NH3-N removal ability was significantly improved from 1.5 mg/L to more than 3 mg/L. Influent to the UBACF with higher turbidity could be coped with through the primary filtration of the ceramisite layer combined with fluid-bed technology, which gave the carbon bed a low-turbidity environment of less than 1.0 NTU. The backwashing parameters and carbon abrasion rate of the two processes were almost the same.

  16. Vertical flow constructed wetlands for domestic wastewater treatment on tropical conditions: effect of several design parameters

    DEFF Research Database (Denmark)

    Bohorquez, Eliana; Paredes, Diego; Arias, Carlos Alberto

    Vertical flow constructed wetlands (VFWC) design and operation takes into account several variables which affect performance its performance. These aspects had been evaluated and documented among others in countries like USA, Denmark, Austria. In contrast, VFCW had not been studied in tropical...

  17. Water and mass budgets of a vertical-flow constructed wetland used for wastewater treatment

    NARCIS (Netherlands)

    Meuleman, Arthur F M; Van Logtestijn, Richard; Rijs, Gerard B J; Verhoeven, Jos T A

    To estimate the nutrient and organic matter (Biological Oxygen Demand (BODs) and Chemical Oxygen Demand (COD)) removal capacity of a constructed vertical-flow wetland in The Netherlands, a water and nutrient budget study was conducted. Also bacterial water quality enhancement was measured. The

  18. Flow-diverting Stent in the Treatment of Cervical Carotid Dissection and Pseudoaneurysm: Review of Literature and Case Report. (United States)

    Baptista-Sincos, Anna Paula Weinhardt; Simplício, Aline Bigatão; Sincos, Igor Rafael; Leaderman, Alex; Neto, Fernando Saliture; Moraes, Adjaldes; Aun, Ricardo


    The endovascular technique has been recommended over the past few years to extracranial carotid dissection and pseudoaneurysm with promising results, especially after medical therapy failure. Flow-diverting stents are an alternative for complex cases. These stents have proven to be effective treatment devices for intracranial aneurysms. The reference list of Pham's systematic review, published in 2011, and Seward's literature review, published in 2015, was considered, as well as all new articles with eligible features. Search was conducted on specific databases: MEDLINE and Literatura Latino-Americana e do Caribe em Ciências da Saúde. For carotid dissection and pseudoaneurysm, our review yielded 3 published articles including 12 patients. The technical success rate of flow-diverting stent was 100% with no procedural complication described. Mean clinical follow-up was 27.2 months (range 5-48), and in 5 months' angiographic follow-up, all lesions had healed. No new neurological events were reported during the clinical follow-up. Flow diverter stent use on intracranial and peripheral vascular surgery demonstrates satisfactory initial results, but it is still under investigation. There are very few cases treated till now and the initial results with flow-diverting stents to cervical carotid dissection are promising. In well-selected cases, where simple embolization or conventional stent is not appropriate, this technic may be considered. Copyright © 2017 Elsevier Inc. All rights reserved.


    Directory of Open Access Journals (Sweden)

    Dariusz Zdebik


    Full Text Available This paper presents a method for calibration of activated sludge model with the use of computer program BioWin. Computer scheme has been developed on the basis of waste water treatment plant operating in the sequential – flow technology. For calibration of the activated sludge model data of influent and treated effluent from the existing object were used. As a result of conducted analysis was a change in biokinetic model and kinetic parameters parameters of wastewater treatment facilities. The presented method of study of the selected parameters impact on the activated sludge biokinetic model (including autotrophs maximum growth rate, the share of organic slurry in suspension general operational, efficiency secondary settling tanks can be used for conducting simulation studies of other treatment plants.

  20. Treatment of high-strength wastewater in tropical constructed wetlands planted with Sesbania sesban: Horizontal subsurface flow versus vertical downflow

    DEFF Research Database (Denmark)

    Dan, Truong Hoang; Quang, Le Nhat; Chiem, Nguyen Huu


    Treatment of various types of wastewaters is an urgent problem in densely populated areas of many tropical countries. We studied the potential of using Sesbania sesban, an N2-fixing shrub, in constructed wetland systems for the treatment of high-strength wastewater. A replicated horizontal...... subsurface flow system and a saturated vertical downflow system was established with planted and unplanted beds to assess the effects of system design and presence of plants on treatment performance. The systems were loaded with a mixture of domestic and pig farm wastewater at three hydraulic loading rates...... of 80, 160 and 320mmd-1. The S. sesban plants grew very well in the constructed wetland systems and produced 17.2-20.2kgdry matterm-2year-1 with a high nitrogen content. Mass removal rates and removal rate constants increased with loading rate, but at 320mmd-1 the effluent quality was unacceptable...

  1. Flow rate analysis of wastewater inside reactor tanks on tofu wastewater treatment plant (United States)

    Mamat; Sintawardani, N.; Astuti, J. T.; Nilawati, D.; Wulan, D. R.; Muchlis; Sriwuryandari, L.; Sembiring, T.; Jern, N. W.


    The research aimed to analyse the flow rate of the wastewater inside reactor tanks which were placed a number of bamboo cutting. The resistance of wastewater flow inside reactor tanks might not be occurred and produce biogas fuel optimally. Wastewater from eleven tofu factories was treated by multi-stages anaerobic process to reduce its organic pollutant and produce biogas. Biogas plant has six reactor tanks of which its capacity for waste water and gas dome was 18 m3 and 4.5 m3, respectively. Wastewater was pumped from collecting ponds to reactors by either serial or parallel way. Maximum pump capacity, head, and electrical motor power was 5m3/h, 50m, and 0.75HP, consecutively. Maximum pressure of biogas inside the reactor tanks was 55 mbar higher than atmosphere pressure. A number of 1,400 pieces of cutting bamboo at 50-60 mm diameter and 100 mm length were used as bacteria growth media inside each reactor tank, covering around 14,287 m2 bamboo area, and cross section area of inner reactor was 4,9 m2. In each reactor, a 6 inches PVC pipe was installed vertically as channel. When channels inside reactor were opened, flow rate of wastewater was 6x10-1 L.sec-1. Contrary, when channels were closed on the upper part, wastewater flow inside the first reactor affected and increased gas dome. Initially, wastewater flowed into each reactor by a gravity mode with head difference between the second and third reactor was 15x10-2m. However, head loss at the second reactor was equal to the third reactor by 8,422 x 10-4m. As result, wastewater flow at the second and third reactors were stagnant. To overcome the problem pump in each reactor should be installed in serial mode. In order to reach the output from the first reactor and the others would be equal, and biogas space was not filled by wastewater, therefore biogas production will be optimum.

  2. Analytical treatments of micro-channel and micro-capillary flows


    Adachi, T; Sambasivam, R; Durst, F; Filimonov, D; 3rd Micro and Nano Flows Conference (MNF2011)


    This paper was presented at the 3rd Micro and Nano Flows Conference (MNF2011), which was held at the Makedonia Palace Hotel, Thessaloniki in Greece. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, Aristotle University of Thessaloniki, University of Thessaly, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute. ...

  3. A Water Treatment Case Study for Quantifying Model Performance with Multilevel Flow Modelling

    DEFF Research Database (Denmark)

    Nielsen, Emil Krabbe; Bram, Mads Valentin; Frutiger, Jerome


    Decision support systems are a key focus of research on developing control rooms to aid operators in making reliable decisions, and reducing incidents caused by human errors. For this purpose, models of complex systems can be developed to diagnose causes or consequences for specific alarms. Model...... plant experiments are used for validation of simple Multilevel Flow Modelling models of a hydrocyclone unit for oil removal from produced water....

  4. Individualized model predicts brain current flow during transcranial direct-current stimulation treatment in responsive stroke patient. (United States)

    Datta, Abhishek; Baker, Julie M; Bikson, Marom; Fridriksson, Julius


    Although numerous published reports have demonstrated the beneficial effects of transcranial direct-current stimulation (tDCS) on task performance, fundamental questions remain regarding the optimal electrode configuration on the scalp. Moreover, it is expected that lesioned brain tissue will influence current flow and should therefore be considered (and perhaps leveraged) in the design of individualized tDCS therapies for stroke. The current report demonstrates how different electrode configurations influence the flow of electrical current through brain tissue in a patient who responded positively to a tDCS treatment targeting aphasia. The patient, a 60-year-old man, sustained a left hemisphere ischemic stroke (lesion size = 87.42 mL) 64 months before his participation. In this study, we present results from the first high-resolution (1 mm(3)) model of tDCS in a brain with considerable stroke-related damage; the model was individualized for the patient who received anodal tDCS to his left frontal cortex with the reference cathode electrode placed on his right shoulder. We modeled the resulting brain current flow and also considered three additional reference electrode positions: right mastoid, right orbitofrontal cortex, and a "mirror" configuration with the anode over the undamaged right cortex. Our results demonstrate the profound effect of lesioned tissue on resulting current flow and the ability to modulate current pattern through the brain, including perilesional regions, through electrode montage design. The complexity of brain current flow modulation by detailed normal and pathologic anatomy suggest: (1) That computational models are critical for the rational interpretation and design of individualized tDCS stroke-therapy; and (2) These models must accurately reproduce head anatomy as shown here. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. Carbon sequestration in surface flow constructed wetland after 12 years of swine wastewater treatment (United States)

    Constructed wetlands used for the treatment of swine wastewater may potentially sequester significant amounts of carbon. In past studies, we evaluated the treatment efficiency of wastewater in marsh-pond-marsh design wetland system. The functionality of this system was highly dependent on soil carbo...

  6. Performance of Four Full-Scale Artificially Aerated Horizontal Flow Constructed Wetlands for Domestic Wastewater Treatment

    Directory of Open Access Journals (Sweden)

    Eleanor Butterworth


    Full Text Available A comparison of the performance of four full-scale aerated horizontal flow constructed wetlands was conducted to determine the efficacy of the technology on sites receiving high and variable ammonia loading rates not yet reported in the literature. Performance was assessed in terms of ammonia and solids removal, hydraulic conductivity and mixing patterns. The capability of systems to produce ammonium effluent concentrations <3 mgNH4+-N/L was observed across all sites in systems receiving variable loadings between 0.1 and 13.0 gNH4+-N/m2/d. Potential resilience issues were observed in relation to response to spike loadings posited to be due to an insufficient nitrifying population within the beds. Hydraulic conductivity and flow mixing patterns observed suggested deterioration of the reactor effective volume over time. Overall, the study demonstrates the efficacy of the technology where ammonium removal is required on small sites receiving high and variable flow rates, with adequate removal of organics and solids, but no significant benefit to the long term hydraulics of the system.

  7. Test study of the optimal design for hydraulic performance and treatment performance of free water surface flow constructed wetland. (United States)

    Guo, Changqiang; Cui, Yuanlai; Dong, Bin; Luo, Yufeng; Liu, Fangping; Zhao, Shujun; Wu, Huirong


    Orthogonal tests with mixed levels of design parameters of a free water surface flow constructed wetland were performed to assess their effect on hydraulic and treatment performance, and discover the relationship between the design parameters and the two performances. The results showed that water depth, plant spacing, and layout of in- and outlet mainly affected the two performances. Under 40cm depth, central pass of in- and outlet, 1.8m 3 /h flow rate, 20cm plant spacing, 2:1 aspect ratio, and Scripus tabernaemontani as the plant species, treatment performance of 5.3% TN, 6.1% TP and 15.6% TSS removal efficiencies and a high hydraulic performance of 0.854e, 0.602MI were achieved. There was no significant correlation between the design parameters and the two performances. The relationship among various hydraulic indicators and that among the purification indicators displayed extremely significant correlation. However, there was no significant correlation between hydraulic and treatment performance. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Cone-beam CT: an additional imaging tool in the interventional treatment and management of low-flow vascular malformations. (United States)

    Lightfoot, Christopher B; Ju, Yang; Dubois, Josée; Abdolell, Mohamed; Giroux, Marie-France; Gilbert, Patrick; Therasse, Eric; Oliva, Vincent; Soulez, Gilles


    To evaluate the impact of cone-beam computed tomography (CT) during sclerotherapy of low-flow vascular malformations. Eighty-seven cone-beam CT examinations were acquired during 81 sclerotherapy treatments of low-flow malformations in 48 patients: 81 were performed to evaluate sclerosing agent diffusion and six were performed to evaluate needle or catheter positioning before injection of therapeutic agent. Image quality was rated by two observers. Clinical impact of cone-beam CT in the assessment of therapeutic agent diffusion, needle or catheter positioning, subsequent treatment planning, and complication detection was evaluated. The κ-statistic was used to assess interobserver reliability and proportions, with associated 95% confidence intervals (CIs). All cone-beam CT images were successfully acquired. Image quality was rated as excellent or good for the majority of studies, with substantial interobserver reliability (κ = 0.648). Cone-beam CT studies improved assessment of therapeutic agent diffusion in 83% of cases (67 of 81; 95% CI, 75%-91%) for observer 1, who had access to ultrasound, fluoroscopic, and digital subtraction angiographic (DSA) imaging, and in 95% of cases (77 of 81; 95% CI, 90%-100%) for observer 2, who had access to only stored fluoroscopic spot radiographs and DSA images. Cone-beam CT impacted planning of the next treatment session in 49% of cases (40 of 81; 95% CI, 38%-60%). In 7% of cases (six of 81; 95% CI, 1%-13%), complications such as migration of therapeutic agent or compression of upper airways were detected that were not seen with other imaging. Cone-beam CT can be a useful adjunctive imaging tool, providing information to help decision-making during percutaneous sclerotherapy and ongoing management of low-flow vascular malformations. Copyright © 2013 SIR. Published by Elsevier Inc. All rights reserved.

  9. Reduced hypothalamic blood flow after radiation treatment of nasopharyngeal cancer: SPECT studies in 34 patients

    International Nuclear Information System (INIS)

    Chieng, P.U.; Huang, T.S.; Chang, C.C.; Chong, P.N.; Tien, R.D.; Su, C.T.


    To determine the effect of cranial irradiation on hypothalamic blood flow, the authors performed 44 regional cerebral blood flow studies with 99mTc hexamethyl propyleneamine oxime (HMPAO) single-photon emission CT (SPECT) on four normal volunteers and 34 patients with pathologically proved nasopharyngeal cancer. Twenty-three men and 15 women, 30-65 years old, were divided into four study groups: group 1 served as a control and consisted of four normal volunteers and six patients studied prior to cranial irradiation; group 2 patients had cranial irradiation half a year before the SPECT study (n = 12, one from group 1); group 3 patients were irradiated 1 year before the study (n = 13, three from group 1 and two from group 2); and group 4 patients were irradiated at least 5 years before SPECT imaging (n = 9). Six patients were studied twice. Quantification of the 99mTc-HMPAO brain SPECT studies was done separately by three radiologists to obtain the hypothalamus/occipital (H/O) and hypothalamus/parasagittal (H/P) ratios. Endocrinologic studies were performed in all cases and the hypothalamus-thyrotroph-thyroid, hypothalamus-gonadotroph-testis (ovary), hypothalamus-lactotroph, hypothalamus-somatotroph, and hypothalamus-corticotroph-adrenal axes were evaluated separately. They determined that regional hypothalamic blood flow was reduced after cranial irradiation in patients with nasopharyngeal cancer. The H/O ratio of groups 3 and 4 did not differ from that of group 2 (one-half year after cranial irradiation). The H/O ratio was significantly reduced 6 months and 1 year after cranial irradiation; mean ± SD = 0.5801 ± 0.0829 (p less than .025), 0.5725 ± 0.0791 (p less than .01) versus 0.6477 ± 0.0458 before cranial irradiation, respectively

  10. Endovascular treatment of AICA flow dependent aneurysms. A report of three cases and review of the literature. (United States)

    Mahmoud, M; El Serwi, A; Alaa Habib, M; Abou Gamrah, S


    Peripheral anterior inferior cerebellar artery (AICA) aneurysms are rare, accounting for less than 1% of all cerebral aneurysms. To our knowledge 34 flow-related cases including the present study have been reported in the literature. Three patients harbouring four flow dependent aneurysms were referred to our institution. Two patients presented with subarachnoid hemorrhage, one presented with cerebellar manifestations. They were all treated by endovascular embolization of the aneurysm as well as the parent artery using liquid embolic material. Two cases were embolized using NBCA, Onyx was used in the third case. No bleeding or rebleeding were encountered during the follow-up period which ranged from five to nine months. One patient developed facial palsy, cerebellar symptoms and sensorineural hearing loss. The remaining two cases did not develop any post treatment neurological complications. Endovascular management of flow-dependent AICA aneurysms by parent artery occlusion is feasible and efficient in terms of rebleeding prevention. Post embolization neurological complications are unpredictable. This depends upon the adequacy of collaterals from other cerebellar arteries.

  11. Macro and micro mechanics behavior of granite after heat treatment by cluster model in particle flow code (United States)

    Tian, Wen-Ling; Yang, Sheng-Qi; Huang, Yan-Hua


    In this paper, a cluster model in particle flow code was used to simulate granite specimens after heat treatment under uniaxial compression. The results demonstrated that micro-cracks are randomly distributed in the specimen when the temperature is below 300 {°} C, and have partial coalescence when the temperature is up to 450 {°} C, then form macro-cracks when the temperature is above 600 {°} C. There is more inter-granular cracking than intra-granular cracking, and their ratio increases with increasing temperature. The micro-cracks are almost constant when the temperature decreases from 900 {°} C to room temperature, except for quartz α -β phase transition temperature (573 {°} C). The fracture evolution process is obviously affected by these cracks, especially at 600-900 {°} C. Elevated temperature leads to easily developed displacement between the grains, and the capacity to store strain energy becomes weaker, corresponding to the plasticity of granite after heat treatment.

  12. Solar disinfection for the post-treatment of greywater by means of a continuous flow reactor. (United States)

    Pansonato, Natália; Afonso, Marcos V G; Salles, Carlos A; Boncz, Marc A; Paulo, Paula L


    SODIS (solar disinfection) is a low-cost alternative for water decontamination. The method is based on the exposure of water, contained in PET bottles, to direct sunlight, and mainly its UV-A and infrared components. The present research studied SODIS as a low cost alternative for the inactivation of Escherichia coli (E. coli) in treated greywater, aiming at its reuse for more noble applications. Experiments were performed in (i) batch mode (2 L PET-bottles), testing the effect of turbidity on system efficiency and, (ii) in a continuous pilot-scale reactor prototype (51 L, using interconnected 2 L-PET bottles), testing hydraulic retention times (HRT) of 18 and 24 h. Samples were exposed to an average solar radiation intensity of 518 W/m2. The results obtained indicate that the SODIS system has potential for total coliforms and E. coli inactivation in the pre-treated greywater, reaching 2.1 log units E. coli inactivation in batch experiments for low turbidity samples (21 NTU), and > 2 log units inactivation of total coliforms (and E. coli, when present) for the 24 h HRT-continuous prototype. The continuous flow prototype needs more testing and structural improvements to cope with the difficulties posed by algae growth, as they complicate maintaining conditions of constant flow and make frequent maintenance inevitable.

  13. Can different physicians providing urgent and non-urgent treatment improve patient flow in emergency department? (United States)

    Yau, Flora Fei-Fei; Tsai, Tsung-Cheng; Lin, Yan-Ren; Wu, Kuan-Han; Syue, Yuan-Jhen; Li, Chao-Jui


    Emergency Department (ED) overcrowding is a worldwide problem, and it might be caused by prolonged patient stay in the ED. This study tried to analyze if different practice models influence patient flow in the ED. A retrospective, 1-year cohort study was conducted across two EDs in the largest healthcare system in Taiwan. A total of 37,580 adult non-trauma patients were involved in the study. The clinical practice between two ED practice models was compared. In one model, urgent and non-urgent patients were treated by different emergency physicians (EPs) separately (separated model). In the other, EPs treated all patients assigned randomly (merged model). The ED length of stay (LOS), diagnostic tool use (including laboratory examinations and computed tomography scans), and patient dispositions (including discharge, general ward admission, intensive care unit (ICU) admissions, and ED mortality) were selected as outcome indicators. Patients discharged from ED had 0.4h shorter ED LOS in the separated model than in merged model. After adjusting for the potential confounding factors through regression model, there was no difference of patient disposition of the two practice models. However, the separated model showed a slight decrease in laboratory examination use (adjusted odds ratio, 0.9; 95% confidence interval, 0.83-0.96) compared with the merged model. The separated model had better patient flow than the merged model did. It decreased the ED LOS in ED discharge patients and laboratory examination use. Copyright © 2017. Published by Elsevier Inc.

  14. Early single centre experience of flow diverting stents for the treatment of cerebral aneurysms. (United States)

    Toma, Ahmed K; Robertson, Fergus; Wong, Ken; Joshi, Yogish; Haridas, Avinash; Grieve, Joan; Watkins, Laurence D; Kitchen, Neil D; Brew, Stefan


    The flow diverting stent (FDS) is a relatively new endovascular therapeutic tool specifically designed to reconstruct the parent artery and divert blood flow along the normal anatomical course and away from the aneurysm neck and dome. Retrospective review of prospectively built clinical and imaging database of patients treated with FDS at the National Hospital for Neurology and Neurosurgery, Queen Square, London, UK was done. Between 18/03/2008 and 10/11/2011, 80 patients underwent 84 FDS insertion procedures for various indications. Mean duration of clinical follow-up was 11.3 ± 9.3 months and of imaging follow-up was 10.6 ± 9.3 months. Sixty-seven had anterior circulation aneurysms while 17 had posterior circulation aneurysms. Seven (8.3%) patients died (two probably not related, giving a procedure-related mortality of 5.9%), eight had permanent new deficit (9.5%), 20 had transient deficit (23%) and 49 (58%) had no complications. There was a trend towards bad outcome with larger posterior circulation aneurysms. Angiographic follow-up showed 38% cure rate at 6 months and 61% at 12 months. FDS should only be used following multidisciplinary discussion in selected patients. Further data is required regarding long-term safety, efficacy and indications.

  15. Deficits in Regional Cerebral Blood Flow on Brain SPECT Predict Treatment Resistant Depression. (United States)

    Amen, Daniel G; Taylor, Derek V; Meysami, Somayeh; Raji, Cyrus A


    Depression remains an important risk factor for Alzheimer's disease, yet few neuroimaging biomarkers are available to identify treatment response in depression. To analyze and compare functional perfusion neuroimaging in persons with treatment resistant depression (TRD) compared to those experiencing full remission. A total of 951 subjects from a community psychiatry cohort were scanned with perfusion single photon emission computed tomography (SPECT) of the brain in both resting and task related settings. Of these, 78% experienced either full remission (n = 506) or partial remission (n = 237) and 11% were minimally responsive (n = 103) or non-responsive (11%. n = 106). Severity of depression symptoms were used to define these groups with changes in the Beck Depression Inventory prior to and following treatment. Voxel-based analyses of brain SPECT images from full remission compared to the worsening group was conducted with the statistical parametric mapping software, version 8 (SPM 8). Multiple comparisons were accounted for with a false discovery rate (p <  0.001). Persons with depression that worsened following treatment had reduced cerebral perfusion compared to full remission in the multiple regions including the bilateral frontal lobes, right hippocampus, left precuneus, and cerebellar vermis. Such differences were observed on both resting and concentration SPECT scans. Our findings identify imaging-based biomarkers in persons with depression related to treatment response. These findings have implications in understanding both depression to prognosis and its role as a risk factor for dementia.

  16. Reduction of protease activity in milk by continuous flow high-intensity pulsed electric field treatments. (United States)

    Bendicho, S; Barbosa-Cánovas, G V; Martín, O


    High-intensity pulsed electric field (HIPEF) is a non-thermal food processing technology that is currently being investigated to inactivate microorganisms and certain enzymes, involving a limited increase of food temperature. Promising results have been obtained on the inactivation of microbial enzymes in milk when suspended in simulated milk ultrafiltrate. The aim of this study was to evaluate the effectiveness of continuous HIPEF equipment on inactivating a protease from Bacillus subtilis inoculated in milk. Samples were subjected to HIPEF treatments of up to 866 micros of squared wave pulses at field strengths from 19.7 to 35.5 kV/cm, using a treatment chamber that consisted of eight colinear chambers connected in series. Moreover, the effects of different parameters such as pulse width (4 and 7 micros), pulse repetition rates (67, 89, and 111 Hz), and milk composition (skim and whole milk) were tested. Protease activity decreased with increased treatment time or field strength and pulse repetition rate. Regarding pulse width, no differences were observed between 4 and 7 micros pulses when total treatment time was considered. On the other hand, it was observed that milk composition affected the results since higher inactivation levels were reached in skim than in whole milk. The maximum inactivation (81%) was attained in skim milk after an 866-micros treatment at 35.5 kV/cm and 111 Hz.

  17. [Impacts on carotid arterial vessel and blood flow in treatment of carotid atherosclerosis with acupuncture and moxibustion]. (United States)

    Zhang, Wen-Lai; Wang, Wei-Zhi


    To assess the impacts of acupuncture and moxibustion on carotid arterial vascular structure and blood flow parameters for the patients with carotid arteriosclerosis. Sixty-eight cases were randomized into an acupuncture-moxibustion group (35 cases) and a medication group (33 cases). In the acupuncture-moxibustion group, Renying (ST 9), Neiguan (PC 6), Zusanli (ST 36), etc. were selected, moxibustion was applied at Zusanli (ST 36). In the medication group, Enteric-coated aspirin was taken orally. The high-frequency ultrasonography was applied to detect common carotid artery (CCA), intima-media thickness (IMT), peak systolic velocity (PSV), end diastolic velocity (EDV), pulsatility index (PI) and resistance index (RI) before and after treatment for the comparative analysis. After treatment, in comparison between acupuncture-moxibustion group and medication group, CCA got bigger [(8.16 +/- 0.80) mm vs (7.69 +/- 0.61) mm, P Acupuncture and moxibustion provides a good efficacy on the improvement in carotid arteriosclerosis and blood flow in carotid artery, which contributes to the alleviation of ischemic cerebrovascular diseases and prevention from the occurrence and development of them.

  18. Homoeopathic medicine Mercurius solubilis treatment improves cerebral blood flow and memory in experimentally induced Dementia in rats

    Directory of Open Access Journals (Sweden)

    Kashif Hanif


    Full Text Available Background: Mercurius solubilis (Merc. sol is a known, accepted homoeopathic medicine for the treatment of various mouth, throat, eye, and ear infections. Previous studies suggested that Merc. sol has anti-inflammatory properties which could be beneficial in memory impairment. Objective: The present study was designed to investigate the effect of Merc. sol on learning and memory and cerebral blood flow (CBF in the rat model of impaired learning and memory function induced by intracerebroventricularly (ICV administered streptozotocin (STZ. Materials and Methods: The different potencies of Merc. sol (6, 30, 200, and 1M were given for 17 days in memory-impaired rats, induced by ICV administration of STZ (3 mg/kg. The Morris water maze test was used to evaluate the learning and memory function on the 14th, 15th, and 16th day. The laser doppler flow meter was used to measure CBF on the 17th day. Results: There was a significant reduction in CBF along with learning and memory functions in STZ (ICV-treated rats, which were significantly attenuated by the treatment of Merc. sol at all potencies (6, 30, 200, and 1M. Conclusion: Our results demonstrated the effectiveness of Merc. sol in improving memory function and CBF. Thus, it could be used as a therapeutic agent in dementia.

  19. Life cycle assessment of vertical and horizontal flow constructed wetlands for wastewater treatment considering nitrogen and carbon greenhouse gas emissions. (United States)

    Fuchs, Valerie J; Mihelcic, James R; Gierke, John S


    Life cycle assessment (LCA) is used to compare the environmental impacts of vertical flow constructed wetlands (VFCW) and horizontal flow constructed wetlands (HFCW). The LCAs include greenhouse gas (N(2)O, CO(2) and CH(4)) emissions. Baseline constructed wetland designs are compared to different treatment performance scenarios and to conventional wastewater treatment at the materials acquisition, assembly and operation life stages. The LCAs suggest that constructed wetlands have less environmental impact, in terms of resource consumption and greenhouse gas emissions. The VFCW is a less impactful configuration for removing total nitrogen from domestic wastewater. Both wetland designs have negligible impacts on respiratory organics, radiation and ozone. Gaseous emissions, often not included in wastewater LCAs because of lack of data or lack of agreement on impacts, have the largest impact on climate change. Nitrous oxide accounts for the increase in impact on respiratory inorganic, and the combined acidification/eutrophication category. The LCAs were used to assess the importance of nitrogen removal and recycling, and the potential for optimizing nitrogen removal in constructed wetlands. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. The implications of household greywater treatment and reuse for municipal wastewater flows and micropollutant loads

    DEFF Research Database (Denmark)

    Revitt, Michael; Eriksson, Eva; Donner, Erica


    for highlighting the potential fate of a election of xenobiotic micropollutants in decentralised greywater treatment systems, and for investigation of the possible implications of greywater recycling for the wider urban water cycle. Potential potable water savings of up to 43% are predicted for greywater recycling...... based on Danish water use statistics and priority substance monitoring at a greywater treatment plant in Denmark. Adsorption represents an important mechanism for the removal of cadmium, nickel, lead and nonylphenol from influent greywater and therefore the disposal route adopted for the generated...


    Sumino, Haruhiko; Wada, Keiji; Syutsubo, Kazuaki; Yamaguchi, Takashi; Harada, Hideki; Ohashi, Akiyoshi

    Anaerobic down-flow hanging sponge (AnDHS) reactor and UASB reactor were operated at 30℃ for over 400 days in order to investigate the process performance and the sludge characteristics of treating methanolic wastewater (2 gCOD/L). The settings OLR of AnDHS reactor and of UASB reactor were 5.0 -10.0 kgCOD/m3/d and 5.0 kgCOD/m3/d. The average of the COD removal demonstrated by both reactors were over 90% throughout the experiment. From the results of methane producing activities and the PCR-DGGE method, most methanol was directly converted to methane in both reactors. The conversion was carried out by different methanogens: one closely related to Methanomethylovorans hollandica in the AnDHS retainted sludge and the other closely related to Methanosarcinaceae and Metanosarciales in the UASB retainted sludge.

  2. Changes in Regional Cerebral Blood Flow with Cognitive Behavioral Therapy in the Treatment of Panic Disorder

    Energy Technology Data Exchange (ETDEWEB)

    Won, K. S.; Jun, S. K.; Kim, J. B.; Jang, E. J. [College of Medicine, Univ. of Kyemyoung, Taegu (Korea, Republic of)


    This study attempted to prospectively investigate changes in regional cerebral blood flow (rCBF) on SPECT and clinical response to cognitive behavioral therapy (CBT) in patients with panic disorder with (PDA) and without (PD) agoraphobia. Using 99mTc-ECD brain SPECT, we assessed brain perfusion in 5 out patients at rest before and after CBT. The subjects received 12 weekly sessions of CBT. Subjects were assessed by Agoraphobic Cognitions Questionnaire, Body Sensations Questionnaire, Beck Anxiety Inventory, Anxiety Sensitivity Index, Beck Depression Inventory-II, Panic Disorder Severity Scale (PDSS) and clinical global improvement (CGI) scale measurement were used as outcome measures. Patients were considered responders to CBT if they are much or very much improved on CGI scale and have a PDSS score at least 30% below their baseline. The scans were statistically analyzed by using statistical parametric mapping (SPM99). The baseline scans were compared to the post-CBT scans by using the statistics option multi subject, different conditions. Of 5 subjects 4 were male, 3 diagnosed PDA, and 4 on anti-anxiety medication. All of the subjects were classified as CBT responders. Their mean pretreatment and posttreatment PDSS were 17.4 (SD=8.2) and 4.2 (SD=3.1), respectively. The results of SPM analysis showed a significant decrease in blood flow after CBT in the thalamus bilaterally and right middle frontal gyrus (Brodmann's area 6). All results were thresholded at an uncorrected p<0.001 (for voxel height) and a corrected p<0.04 (for spatial extent). These preliminary data suggest that SPM analysis of 99mTc-ECD brain SPECT can reveal the change of rCBF in patient with panic disorder before and after CBT and the CBT effect may be associated with limbic and thalamic networks. However this study was a short trial with small number of subjects. Further studies with larger patient cohorts are needed.

  3. Changes in Regional Cerebral Blood Flow with Cognitive Behavioral Therapy in the Treatment of Panic Disorder

    International Nuclear Information System (INIS)

    Won, K. S.; Jun, S. K.; Kim, J. B.; Jang, E. J.


    This study attempted to prospectively investigate changes in regional cerebral blood flow (rCBF) on SPECT and clinical response to cognitive behavioral therapy (CBT) in patients with panic disorder with (PDA) and without (PD) agoraphobia. Using 99mTc-ECD brain SPECT, we assessed brain perfusion in 5 out patients at rest before and after CBT. The subjects received 12 weekly sessions of CBT. Subjects were assessed by Agoraphobic Cognitions Questionnaire, Body Sensations Questionnaire, Beck Anxiety Inventory, Anxiety Sensitivity Index, Beck Depression Inventory-II, Panic Disorder Severity Scale (PDSS) and clinical global improvement (CGI) scale measurement were used as outcome measures. Patients were considered responders to CBT if they are much or very much improved on CGI scale and have a PDSS score at least 30% below their baseline. The scans were statistically analyzed by using statistical parametric mapping (SPM99). The baseline scans were compared to the post-CBT scans by using the statistics option multi subject, different conditions. Of 5 subjects 4 were male, 3 diagnosed PDA, and 4 on anti-anxiety medication. All of the subjects were classified as CBT responders. Their mean pretreatment and posttreatment PDSS were 17.4 (SD=8.2) and 4.2 (SD=3.1), respectively. The results of SPM analysis showed a significant decrease in blood flow after CBT in the thalamus bilaterally and right middle frontal gyrus (Brodmann's area 6). All results were thresholded at an uncorrected p<0.001 (for voxel height) and a corrected p<0.04 (for spatial extent). These preliminary data suggest that SPM analysis of 99mTc-ECD brain SPECT can reveal the change of rCBF in patient with panic disorder before and after CBT and the CBT effect may be associated with limbic and thalamic networks. However this study was a short trial with small number of subjects. Further studies with larger patient cohorts are needed

  4. Percutaneous treatment of a duodenocutaneous high-flow fistula using a new biological plug. (United States)

    Crespo Vallejo, Eduardo; Martinez-Galdamez, Mario; Del Olmo Martínez, Lourdes; Crespo Brunet, Eduardo; Santos Martin, Ernesto


    Enterocutaneous fistula is a challenging entity and a gold-standard treatment is not settled so far. Here, we describe the successful closure of a duodenocutaneous fistula with the use of the Biodesign enterocutaneous fistula plug (Cook Medical), which is derived from a biological plug that has been used in recent years in order to close anorectal fistula tracts.

  5. Reconsidering Urban Sewer and Treatment Facilities in East Africa as Interplay of Flows, Networks and Spaces

    NARCIS (Netherlands)

    Letema, S.C.; Vliet, van B.J.M.; Lier, van J.B.


    Urbanization has brought about concentrations of people in densely populated settlements, resulting in the generation of waste water that needs to be disposed off in a hygienic way to avoid the outbreak of diseases. Decisions on what area to sewer, the nature of sewer schemes and treatment works to

  6. Treatment of fishpond water by recirculating horizontal and vertical flow constructed wetlands in the tropics

    DEFF Research Database (Denmark)

    Konnerup, Dennis; Trang, Ngo Thuy Diem; Brix, Hans


    efficient use of water and less environmental impact. The aim of this study was to assess the suitability of using constructed wetlands (CWs) for the treatment of fishpond water in a recirculating aquaculture system in the Mekong Delta of Vietnam. Water from a fishpond stocked with Nile tilapia (Oreochromis...... and the associated environmental impact can be significantly reduced. © 2011 Elsevier B.V....

  7. Cerebral blood flow and end-tidal PCO2 during prolonged acetazolamide treatment in humans

    DEFF Research Database (Denmark)

    Friberg, L; Kastrup, J; Rizzi, Dominick Albert


    for the beneficial effects of the drug on the symptoms of acute mountain sickness. During the treatment there was a significant 10% decrease of the hematocrit but an unaltered hemoglobin concentration. In combination with data in the literature our studies suggest that the initial CBF increase is a consequence...

  8. Morphologic and Clinical Outcome of Intracranial Aneurysms after Treatment Using Flow Diverter Devices: Mid-Term Follow-Up

    Directory of Open Access Journals (Sweden)

    Anna-Katharina Breu


    Full Text Available Flow diverters (FDs are designed for the endovascular treatment of complex intracranial aneurysm configurations. From February 2009 to March 2013 28 patients (22 females, 6 males were treated with FD; mean age was 57 years. Data, including aneurysm features, clinical presentation, history of previous bleeding, treatment, and follow-up results, are presented. Early postinterventional neurological deficits (transient: n=3/enduring: n=1 appeared in 4/28 patients (14%, and early improvement of neurological symptoms was observed in 7 patients with previous restriction of cranial nerve function. The overall occlusion rate was 20/26 (77%; 59% after 3 months. 77% achieved best results according to O’Kelly-Marotta score grade D with no contrast material filling (70% of those after 3 months. In 4/6 patients who did not achieve grade D, proximal and/or distal stent overlapping ≥5 mm was not guaranteed sufficiently. During follow-up we did not detect any aneurysm recurrence or haemorrhage. In-stent stenosis emerged as the most frequent complication (4/27; 15% followed by 2 cases of vascular obliteration (AICA/VA. In conclusion endovascular reconstruction using a FD represents a modern and effective treatment in those aneurysms that are not suitable for conventional interventional or surgical treatment. The appearance of severe complications was rare.

  9. Hypoxic abdominal stop-flow perfusion in the treatment of advanced pancreatic cancer: a phase II evaluation/trial. (United States)

    Guadagni, S; Clementi, M; Valenti, M; Fiorentini, G; Cantore, M; Kanavos, E; Caterino, G P; Di Giuro, G; Amicucci, G


    In the past decade, some authors have reported objective responses and prolonged median survival times using hypoxic abdominal perfusion (HAP) for the treatment of advanced pancreatic cancer. However, these promising results have not been confirmed by others, making it difficult to define the effectiveness of this loco-regional chemotherapy. The aim of this study, therefore, was to evaluate the response rate, time to disease progression and overall survival following HAP treatment of 22 consecutive patients with advanced pancreatic tumors. Within the period from 1999 to 2003, 22 patients with histological diagnosis of unresectable stage III/IV pancreatic cancer, not responsive to systemic chemotherapy, were treated with mitomycin C 30mg/m(2) and cisplatin 60mg/m(2) by HAP (stop flow technique). Immediately after perfusion, hemofiltration was performed to reduce systemic side toxic effects. Responses were assessed by CT-scan 30days from the end of treatment. Minor or partial responses were confirmed by a second CT-scan 4weeks later. Following 26 treatment cycles no death or technical complications were recorded; four patients (18.2%) achieved a partial response, 2 (9.1%) a minimal response and 13 (59.1%) stable disease. The remaining 3 patients (13.6%) showed progression of the disease. The median time to disease progression was 3 months (range 1-10). The median survival time from the start of regional chemotherapy was 6 months (range 1.9-16), with a 1-year survival rate of 9%. Our data show that HAP is a relatively effective second-line treatment for advanced stage pancreatic cancer with a low complication rate. We do not concur with the opinion of others that HAP is an inactive treatment approach. However, taking into account the invasiveness of this procedure, and associated morbidity and cost, HAP would not appear to be preferable to less invasive loco-regional chemotherapeutic alternatives.

  10. Influence of Continuous Flow Microwave Pre-Treatment on Anaerobic Digestion of Secondary Thickened Sludge for Sustainable Energy Recovery in Sewage Treatment Plant (United States)

    Hephzibah, D.; Kumaran, P.; Saifuddin, N. M.


    This work elucidates the effects of pre-treatment of secondary thickened sludge (STS) for enhancement of biogas production that has great potential to generate energy for the utilization of the sewage treatment plant (STP) itself. Microwave pre-treatment has been adopted for this study. Experiment works have been designed and conducted to examine the effectiveness of continuous flow microwave pre-treatment on the solubility of STS, digestibility of STS and biogas production at a power level of 80 W for 5, 10 and 15 minutes. A few characteristics of the sewage sludge were monitored daily to identify the effect of pre-treatment on the sludge. The soluble chemical oxygen demand (SCOD)/total chemical oxygen demand (TCOD) ratio increased by 0.1, 1.0 and 1.8%, while the volatile fatty acids (VFA) concentration of the pre-treated sludge improved by 4.4, 5.1, 5.9% at the irradiation time of 5, 10 and 15 minutes, respectively at a microwave power level of 80 W. Besides that, the digestate also indicates that the pre-treated sludge undergoes efficient VS removal and TCOD removal after anaerobic digestion compared to the untreated sludge. Moreover, the biogas quantity increased by an average of 19.2, 24.1 and 32.2% in 5, 10 and 15 minutes irradiation time respectively compared to the untreated sludge. The additional quantity of biogas generated has shown a great potential for sustainable energy generation that can be utilized internally by the STP.

  11. Cross-flow filtration with different ceramic membranes for polishing wastewater treatment plant effluent

    DEFF Research Database (Denmark)

    Farsi, Ali; Hammer Jensen, Sofie; Roslev, Peter

    Nowadays the need for sustainable water treatment is essential because water shortages are increasing. Depending on the wastewater treatment plant (WWTP) effluent constituents, the effluent cannot be simply discharged to environment because it contains toxic ions and organic micropollutants which...... are harmful for aquatic organism. A possible strategy to avoid this is to polish the effluent by membrane processes. Different ceramic membranes were studied to test their ability to remove inorganic and organic compounds from the effluent. Hence, various active layers such as mesoporous TiO2 (average nominal...... efficient (Fig. 3). NO3- rejection was to some extent a logarithmic function of membranes’ permeability. The results showed that γ-alumina membrane can be the optimum choice to polish the WWTP effluent compare to the others based on the membrane permeability and selectivity. Bioassays with Daphnia magna...

  12. Odour emission inventory of German wastewater treatment plants--odour flow rates and odour emission capacity. (United States)

    Frechen, F-B


    Wastewater Treatment plants can cause odour emissions that may lead to significant odour annoyance in their vicinity. Thus, over the past 20 years, several measurements were taken of the odour emissions that occur at WWTPs of different sizes, treatment technology, plant design and under different operating conditions. The specific aspects of odour sampling and measurement have to be considered. I presented some of the results of my odour emission measurements 11 years ago. However, it is now necessary to update the figures by evaluating newer measurement results obtained from measurements taken from 1994 to 2003. These are presented in this paper. Also, the paper highlights the odour emission capacity (OEC) measurement technique which characterises liquids and can be used to assess the results achieved by different types of treatment in the liquid phase, e.g. in a sewerage system. In addition, the OEC is a suitable parameter to set standards for the odorant content of industrial wastewaters that are discharged into the publicly owned sewerage system.

  13. Alterations of blood flow pattern after triple stent endovascular treatment of saccular abdominal aortic aneurysm: a porcine model. (United States)

    Oliveira, Jahir Richard DE; Aquino, Maurício DE Amorim; Barros, Svetlana; Pitta, Guilherme Benjamin Brandão; Pereira, Adamastor Humberto


    to determine the blood flow pattern changes after endovascular treatment of saccular abdominal aortic aneurysm with triple stent. we conducted a hemodynamic study of seven Landrace and Large White pigs with saccular aneurysms of the infrarenal abdominal aorta artificially produced according to the technique described. The animals were subjected to triple stenting for endovascular aneurysm. We evaluated the pattern of blood flow by duplex scan before and after stent implantation. We used the non-paired Mann-Whitney test for statistical analysis. there was a significant decrease in the average systolic velocity, from 127.4cm/s in the pre-stent period to 69.81cm/s in the post-stent phase. There was also change in the flow pattern from turbulent in the aneurysmal sac to laminate intra-stent. there were changes in the blood flow pattern of saccular abdominal aortic aneurysm after endovascular treatment with triple stent. determinar as alterações do padrão do fluxo sanguíneo após tratamento endovascular do aneurisma sacular de aorta abdominal com triplo stent. estudo hemodinâmico de sete suínos das raças Landrace e Large White portadores de aneurismas saculares de aorta abdominal infrarrenal artificialmente produzidos segundo técnica descrita. Os animais foram submetidos a implante de triplo stent para correção endovascular do aneurisma e reavaliados por duplex scan quanto ao padrão do fluxo sanguíneo antes e após o implante dos stents. A análise estatística foi realizada com o teste Mann-Whitney não pareado. verificou-se uma queda significativa da velocidade sistólica média de 127,4cm/s na fase pré-stent para 69,81cm/s na fase pós-stent. Houve ainda mudança no padrão do fluxo de turbilhonar no saco aneurismático para laminar intrastent. o estudo demonstrou alterações do padrão do fluxo sanguíneo do aneurisma sacular de aorta abdominal após tratamento endovascular com triplo stent.

  14. Numerical treatment for Carreau nanofluid flow over a porous nonlinear stretching surface (United States)

    Eid, Mohamed R.; Mahny, Kasseb L.; Muhammad, Taseer; Sheikholeslami, Mohsen


    The impact of magnetic field and nanoparticles on the two-phase flow of a generalized non-Newtonian Carreau fluid over permeable non-linearly stretching surface has been analyzed in the existence of all suction/injection and thermal radiation. The governing PDEs with congruous boundary condition are transformed into a system of non-linear ODEs with appropriate boundary conditions by using similarity transformation. It solved numerically by using 4th-5th order Runge-Kutta-Fehlberg method based on shooting technique. The impacts of non-dimensional controlling parameters on velocity, temperature, and nanoparticles volume concentration profiles are scrutinized with aid of graphs. The Nusselt and the Sherwood numbers are studied at the different situations of the governing parameters. The numerical computations are in excellent consent with previously reported studies. It is found that the heat transfer rate is reduced with an increment of thermal radiation parameter and on contrary of the rising of magnetic field. The opposite trend happens in the mass transfer rate.

  15. Treatment of intracranial aneurysms. Reconstruction of the parent artery with flow-diverting (Silk) stent

    DEFF Research Database (Denmark)

    Wagner, Aase; Cortsen, Marie; Hauerberg, John


    the periprocedural complications, immediate result, late complications, imaging follow-up at 6 and 12 months and clinical follow-up at 2-23 months. METHODS: Twenty-two patients with 26 wide-necked or blister-like aneurysms had 23 treatments with implantation of a Silk stent. Eleven patients had re...... (86%) were occluded. CONCLUSION: The effect of the Silk FD in terms of occlusion of the aneurysms seems to occur mainly during the first 6 months after placement but continues during the following time. Most delayed complications occur immediately after discontinuing the anticoagulation medication...

  16. Treatment Wetlands


    Dotro, Gabriela; Langergraber, Günter; Molle, Pascal; Nivala, Jaime; Puigagut, Jaume; Stein, Otto; Von Sperling, Marcos


    Overview of Treatment Wetlands; Fundamentals of Treatment Wetlands; Horizontal Flow Wetlands; Vertical Flow Wetlands; French Vertical Flow Wetlands; Intensified and Modified Wetlands; Free Water Surface Wetlands; Other Applications; Additional Aspects.

  17. Carbon sequestration in a surface flow constructed wetland after 12 years of swine wastewater treatment. (United States)

    Reddy, Gudigopuram B; Raczkowski, Charles W; Cyrus, Johnsely S; Szogi, Ariel


    Constructed wetlands used for the treatment of swine wastewater may potentially sequester significant amounts of carbon. In past studies, we evaluated the treatment efficiency of wastewater in a marsh-pond-marsh design wetland system. The functionality of this system was highly dependent on soil carbon content and organic matter turnover rate. To better understand system performance and carbon dynamics, we measured plant dry matter, decomposition rates and soil carbon fractions. Plant litter decomposition rate was 0.0052 g day(-1) (±0.00119 g day(-1)) with an estimated half-life of 133 days. The detritus layer accumulated over the soil surface had much more humin than other C fractions. In marsh areas, soil C extracted with NaOH had four to six times higher amounts of humic acid, fulvic acid and humin than soil C extracted by cold and hot water, HCl/HF, and Na pyruvate. In the pond area, humic acid, fulvic acid and humin content were two to four times lower than in the marsh area. More soil C and N was found in the marsh area than in the pond area. These wetlands proved to be large sinks for stable C forms.

  18. Purification ability and carbon dioxide flux from surface flow constructed wetlands treating sewage treatment plant effluent. (United States)

    Wu, Haiming; Lin, Li; Zhang, Jian; Guo, Wenshan; Liang, Shuang; Liu, Hai


    In this study, a two-year experiment was carried out to investigate variation of carbon dioxide (CO2) flux from free water surface constructed wetlands (FWS CW) systems treating sewage treatment plant effluent, and treatment performance was also evaluated. The better 74.6-76.6% COD, 92.7-94.4% NH4(+)-N, 60.1-84.7% TN and 49.3-70.7% TP removal efficiencies were achieved in planted CW systems compared with unplanted systems. The planted CW was a net CO2 sink, while the unplanted CW was a net CO2 source in the entire study period. An obvious annual and seasonal variability of CO2 fluxes from different wetland systems was also presented with the average CO2 flux ranging from -592.83mgm(-2)h(-1) to 553.91mgm(-2)h(-1) during 2012-2013. In addition, the net exchange of CO2 between CW systems and the atmosphere was significantly affected by air temperature, and the presence of plants also had the significant effect on total CO2 emissions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Predicting effects of blood flow rate and size of vessels in a vasculature on hyperthermia treatments using computer simulation. (United States)

    Huang, Huang-Wen; Shih, Tzu-Ching; Liauh, Chihng-Tsung


    Pennes Bio Heat Transfer Equation (PBHTE) has been widely used to approximate the overall temperature distribution in tissue using a perfusion parameter term in the equation during hyperthermia treatment. In the similar modeling, effective thermal conductivity (Keff) model uses thermal conductivity as a parameter to predict temperatures. However the equations do not describe the thermal contribution of blood vessels. A countercurrent vascular network model which represents a more fundamental approach to modeling temperatures in tissue than do the generally used approximate equations such as the Pennes BHTE or effective thermal conductivity equations was presented in 1996. This type of model is capable of calculating the blood temperature in vessels and describing a vasculature in the tissue regions. In this paper, a countercurrent blood vessel network (CBVN) model for calculating tissue temperatures has been developed for studying hyperthermia cancer treatment. We use a systematic approach to reveal the impact of a vasculature of blood vessels against a single vessel which most studies have presented. A vasculature illustrates branching vessels at the periphery of the tumor volume. The general trends present in this vascular model are similar to those shown for physiological systems in Green and Whitmore. The 3-D temperature distributions are obtained by solving the conduction equation in the tissue and the convective energy equation with specified Nusselt number in the vessels. This paper investigates effects of size of blood vessels in the CBVN model on total absorbed power in the treated region and blood flow rates (or perfusion rate) in the CBVN on temperature distributions during hyperthermia cancer treatment. Also, the same optimized power distribution during hyperthermia treatment is used to illustrate the differences between PBHTE and CBVN models. Keff (effective thermal conductivity model) delivers the same difference as compared to the CBVN model. The

  20. Predicting effects of blood flow rate and size of vessels in a vasculature on hyperthermia treatments using computer simulation

    Directory of Open Access Journals (Sweden)

    Shih Tzu-Ching


    Full Text Available Abstract Background Pennes Bio Heat Transfer Equation (PBHTE has been widely used to approximate the overall temperature distribution in tissue using a perfusion parameter term in the equation during hyperthermia treatment. In the similar modeling, effective thermal conductivity (Keff model uses thermal conductivity as a parameter to predict temperatures. However the equations do not describe the thermal contribution of blood vessels. A countercurrent vascular network model which represents a more fundamental approach to modeling temperatures in tissue than do the generally used approximate equations such as the Pennes BHTE or effective thermal conductivity equations was presented in 1996. This type of model is capable of calculating the blood temperature in vessels and describing a vasculature in the tissue regions. Methods In this paper, a countercurrent blood vessel network (CBVN model for calculating tissue temperatures has been developed for studying hyperthermia cancer treatment. We use a systematic approach to reveal the impact of a vasculature of blood vessels against a single vessel which most studies have presented. A vasculature illustrates branching vessels at the periphery of the tumor volume. The general trends present in this vascular model are similar to those shown for physiological systems in Green and Whitmore. The 3-D temperature distributions are obtained by solving the conduction equation in the tissue and the convective energy equation with specified Nusselt number in the vessels. Results This paper investigates effects of size of blood vessels in the CBVN model on total absorbed power in the treated region and blood flow rates (or perfusion rate in the CBVN on temperature distributions during hyperthermia cancer treatment. Also, the same optimized power distribution during hyperthermia treatment is used to illustrate the differences between PBHTE and CBVN models. Keff (effective thermal conductivity model delivers the

  1. Emergency Endovascular Treatment of an Acute Traumatic Rupture of the Thoracic Aorta Complicated by a Distal Low-Flow Syndrome

    International Nuclear Information System (INIS)

    Bruninx, Guy; Wery, Didier; Dubois, Eric; El Nakadi, Badih; Dueren, Eric van; Verhelst, Guy; Delcour, Christian


    We report the case of a patient who suffered major trauma following a motorcycle accident that resulted in multiple fractures, bilateral hemopneumothorax, pulmonary contusions, and an isthmic rupture of the aorta with a pseudoaneurysm compressing the descending aorta. This compression was responsible for distal hypotension and low flow, leading to acute renal insufficiency and massive rhabdomyolysis. Due to the critical clinical status of the patient, which prevented any type of open thoracic surgery, endovascular treatment was performed. An initial stent-graft permitted alleviation of the compression and the re-establishment of normal hemodynamic conditions, but its low position did not allow sufficient coverage of the rupture. A second stent-graft permitted total exclusion of the pseudoaneurysm while preserving the patency of the left subclavian artery

  2. Flow- and acetylcholine-induced dilation in small arteries from rats with renovascular hypertension - effect of tempol treatment

    DEFF Research Database (Denmark)

    Christensen, Frank Holden; Stankevicius, Edgaras; Hansen, Thomas


    -treated animals, while only the relaxation was improved by the NO donor, S-nitroso-N-acetylpenicillamine (SNAP). In conclusion renovascular hypertension selectively inhibits flow-induced NO-mediated vasodilatation, while EDHF-type vasodilatation remains unaffected, suggesting that high blood pressure leads...... blood pressure and tempol treatment. Simultaneous measurements of NO-concentration and relaxation were performed in isolated coronary arteries from the same animals. As compared to vehicle-treated rats, both acetylcholine-induced relaxation and NO-concentration increased in arteries from tempol......-induced dilatation remained normal. Measured by dihydroethidium staining there was an increased amount of superoxide in arteries from vehicle-treated rats, but not from tempol-treated rats. Expression by immunoblotting of endothelial NO synthase and the NAD(P)H oxidase subunit p47phox remained unaffected by high...

  3. Effects of antipsoriatic treatment on cutaneous blood flow in psoriasis measured by 133Xe washout method and laser Doppler velocimetry

    International Nuclear Information System (INIS)

    Klemp, P.; Staberg, B.


    In 8 patients with psoriasis vulgaris, the cutaneous blood flow (CBF) was measured simultaneously in both involved and uninvolved psoriatic skin before (i.e., on the first day of hospitalization) and on the 3rd, 7th, 14th, and 28th days of treatment with tar. The 133 Xe washout method was used after epicutaneous labeling and compared to the laser Doppler velocimetry (LDV) technique. Control experiments were performed in 10 normal individuals. Before treatment the mean CBF in involved psoriatic skin was 62.6 +/- 18.7 SD ml X (100 g X min)-1, which is significantly higher than CBF of uninvolved skin in psoriatic patients, 9.5 +/- 4.0 SD ml X (100 g X min)-1, (p less than 0.01) and is 13.6 times higher than CBF in the normal individuals (p less than 0.01). Fifty hours following onset of treatment (i.e., after only 2 applications of tar), mean CBF of the involved psoriatic skin had decreased significantly to 35.0 +/- 13.9 SD ml X (100 g X min)-1, (p less than 0.01), which was not statistically different from the CBF on the 7th day. During the following weeks, the CBF in involved psoriatic skin decreased at a more moderate rate than that observed during the first week and was 15.0 +/- 6.1 SD ml X (100 g X min)-1 on the 28th day. This value is not significantly different from the CBF of uninvolved skin in these patients. At the end of treatment, the CBF of the uninvolved skin had decreased significantly (p less than 0.05) in all the patients to values similar to those observed in the skin of normal individuals. A parallel decline was observed in a clinical psoriatic score index; however, it is not known whether the observed decrease in CBF was preceded or succeeded by the clinical improvement

  4. Investigation of Performance and Rotor Tip Flow Field in a Low Speed Research Compressor with Circumferential Groove Casing Treatment at Varying Tip Clearance

    Directory of Open Access Journals (Sweden)

    Matthias Rolfes


    Full Text Available Experimental investigations in a single-stage low speed axial research compressor are presented. The influence of four different rotor tip clearances on the overall compressor performance and on the rotor tip flow field is investigated in configurations with and without circumferential groove casing treatments. Piezo-resistive pressure transducers are used to capture the unsteady flow field in the rotor tip region. The investigated casing groove is effectively working at the three largest investigated tip clearance sizes. The largest achieved operating range increase by the groove is 6.9%. The groove can delay the upstream movement of the flow interface between leakage flow and main flow and thus increase the stable operating range. Rotating instabilities are shown to exist at large tip clearance sizes in throttled operating conditions. Their amplitudes can be damped by the casing groove. No modal activities could be detected in the current single-stage compressor build.

  5. Characterization of wastewater treatment by two microbial fuel cells in continuous flow operation. (United States)

    Kubota, Keiichi; Watanabe, Tomohide; Yamaguchi, Takashi; Syutsubo, Kazuaki


    A two serially connected single-chamber microbial fuel cell (MFC) was applied to the treatment of diluted molasses wastewater in a continuous operation mode. In addition, the effect of series and parallel connection between the anodes and the cathode on power generation was investigated experimentally. The two serially connected MFC process achieved 79.8% of chemical oxygen demand removal and 11.6% of Coulombic efficiency when the hydraulic retention time of the whole process was 26 h. The power densities were 0.54, 0.34 and 0.40 W m(-3) when electrodes were in individual connection, serial connection and parallel connection modes, respectively. A high open circuit voltage was obtained in the serial connection. Power density decreased at low organic loading rates (OLR) due to the shortage of organic matter. Power generation efficiency tended to decrease as a result of enhancement of methane fermentation at high OLRs. Therefore, high power density and efficiency can be achieved by using a suitable OLR range.

  6. Enzymatic treatment for controlling irreversible membrane fouling in cross-flow humic acid-fed ultrafiltration

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Chien-Hwa [Department of Civil and Environment Engineering, Nanya Institute of Technology, Taoyuan, Taiwan (China); Fang, Lung-Chen; Lateef, Shaik Khaja [Graduate Institute of Environmental Engineering, National Taiwan University, Taipei, Taiwan (China); Wu, Chung-Hsin, E-mail: [Department of Chemical and Materials Engineering, National Kaohsiung University of Applied Sciences, 415 Chien Kung Road, Kaohsiung 807, Taiwan (China); Lin, Cheng-Fang [Graduate Institute of Environmental Engineering, National Taiwan University, Taipei, Taiwan (China)


    Exploring reasonable ways to remove foulant is of great importance in order to allow sustainable operation of ultrafiltration (UF) membranes in water/wastewater treatment technology. Compounds of organic and inorganic origin largely contribute to irreversible fouling. This study attempted to remove problem of UF membrane fouling by using four different enzymes including {alpha}-amylase, lipase, cellulase and protease. This investigation showed that none of the above mentioned enzymes was found to be effective for the removal of foulant when used alone. However, when these enzymes were used in combination with NaOH and citric acid, about 90% cleaning was achieved. The addition of non-ionic surfactant to the enzymatic solution appears to increase the efficiency of flux recovery by reducing the adhesion of foulant species to the membrane surface through the decrease of contact angle. Field emission gun scanning electron microscopy, Fourier transform infrared spectroscopy and atomic force microscopy (AFM) techniques were employed to qualitatively illustrate the foulant characteristics. The surface roughness through AFM was used to explain the potential mechanism for the enzymatic cleaning.

  7. Numerical investigation of the influence of electromagnetic treatment on calcium carbonate scaling rate in non-isothermal pipe flow (United States)

    Kireev, Victor; Kovaleva, Liana; Isakov, Andrey; Alimbekova, Sofya


    In the present paper, an attempt to explain the mechanisms of the electromagnetic field influence on the process of formation and deposition of calcium carbonate from supersaturated brine solution has been made using numerical modeling. The one-dimensional mathematical model of the brine laminar flow through a cylindrical tube with non-uniform temperature field is written in the form of the system of transient convection-diffusion-reaction partial differential equations describing temperature field and chemical components concentrations (Ca2+, HCO3-, CaCO3). The influence of the temperature on the kinetics of formation of calcium carbonate is taken into account and it is described in accordance with the Arrhenius equation. The kinetics of the calcium carbonate precipitation on the wall of the pipe is given on the basis of the Henry isotherm. It has been established that the electromagnetic treatment of brine solution leads to a decrease of the adsorption rate constant and Henry's constant but it does not significantly influence on the chemical reaction rate of calcium carbonate formation. It also has been shown that treatment with electromagnetic field significantly reduces the amount of calcium carbonate deposits on the wall of the pipe.

  8. Turf soil enhances treatment efficiency and performance of phenolic wastewater in an up-flow anaerobic sludge blanket reactor. (United States)

    Chen, Chunmao; Yao, Xianyang; Li, Qing X; Wang, Qinghong; Liang, Jiahao; Zhang, Simin; Ming, Jie; Liu, Zhiyuan; Deng, Jingmin; Yoza, Brandon A


    Phenols are industrially generated intermediate chemicals found in wastewaters that are considered a class of environmental priority pollutants. Up-flow anaerobic sludge blanket (UASB) reactors are used for phenolic wastewater treatment and exhibit high volume loading capability, favorable granule settling, and tolerance to impact loads. Use of support materials can promote biological productivity and accelerate start-up period of UASB. In the present study, turf soil was used as a support material in a mesophilic UASB reactor for the removal of phenols in wastewater. During sludge acclimatization (45-96 days), COD and phenols in the treatments were both reduced by 97%, whereas these contents in the controls were decreased by 81% and 75%, respectively. The phenol load threshold for the turf soil UASB reactor was greater (1200 mg/L, the equivalent of COD 3000 mg/L) in comparison with the control UASB reactor (900 mg/L, the equivalent of COD 2250 mg/L) and the turf soil UASB reactor was also more resistant to shock loading. Improved sludge settling, shear resistance, and higher biological activity occurred with the turf soil UASB reactor due to the formation of large granular sludge (0.6 mm or larger) in higher relative percentages. Granular sludge size was further enhanced by the colonization of filamentous bacteria on the irregular surface of the turf soil. Copyright © 2018. Published by Elsevier Ltd.

  9. Comparative Study on the Landfill Leachate Treatment in a Vertical Flow Wetland System With/Without Phragmites australis

    Directory of Open Access Journals (Sweden)

    Silviya Lavrova


    Full Text Available The landfill leachate treatment efficiency in a vertical-flow wetland system with and without planted Phragmites australis was investigated. The BOD/COD ratio of the landfill leachate was 0.38. Water samples were taken daily for determination of the COD, BOD, [NH4-N], [NO2-N], [NO3-N] and orthophosphates values. High COD and BOD removal efficiencies and discharge limits in both laboratory systems were achieved. Complete elimination of the ammonium nitrogen from the leachate in the nonvegetated wetland for 13 and 14 days was obtained at a recirculation ratio of 1:1 and 1:2, respectively, and for 9 and 7 days - in the vegetated wetland, at the same recirculation ratios. The initial nitrite nitrogen concentration in the landfill leachate was 17.2 ± 1.1 mg/L, which is 430 times over the discharge limit for these ions. After landfill leachate treatment in the nonvegetated wetland system at the recirculation ratios 1:1 and 1:2, nitrites removal efficiencies of 98.8% and 92.5%, respectively, were achieved. In the vegetated wetland system at the same recirculation ratios, nitrites removal efficiencies of 96.5% and 76.2%, respectively were achieved. Nitrates removal was not observed. The results show that the orthophosphates were assimilated better from the Phragmites australis at longer water resting period.

  10. Performance evaluation of semi continuous vertical flow constructed wetlands (SC-VF-CWs) for municipal wastewater treatment. (United States)

    Kumar, Manoj; Singh, Rajesh


    The present study demonstrated the understating of municipal wastewater treatment in five types of CWs operated under semi continuous vertical flow mode. All CWs treatment conditions show the significantly lower pollutants concentrations. The average NH 4 + -N, TN, NO 2 - -N, NO 3 - -N, SO 4 2- , and PO 4 3- removal efficiency in the ISs-CWs were 83.60%, 82.43%, 15.61%, 48.93%, 80.45%, and 78.94% respectively. The average NO 2 - -N removal efficiency shows that highest nitrite accumulation occurred in the Cont-CWs followed by C-CWs. The lowest increase in the biomass (127.5%) was observed in the Eichhornia crassipes planted in the ISs-CWs. The ISs filtration barrier created in the constructed wetlands was sufficient enough to remove all the pollutants. Principal components EFA 2D deformation plots show the distribution of the various nitrogenous species in the constructed wetlands along different components. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Improvement of the Performance of Graphite Felt Electrodes for Vanadium-Redox-Flow-Batteries by Plasma Treatment

    Directory of Open Access Journals (Sweden)

    Eva-Maria Hammer


    Full Text Available In the frame of the present contribution oxidizing plasma pretreatment is used for the improvement of the electrocatalytic activity of graphite felt electrodes for Vanadium-Redox-Flow-Batteries (VRB. The influence of the working gas media on the catalytic activity and the surface morphology is demonstrated. The electrocatalytical properties of the graphite felt electrodes were examined by cyclic voltammetry and electrochemical impedance spectroscopy. The obtained results show that a significant improvement of the redox reaction kinetics can be achieved for all plasma modified samples using different working gasses (Ar, N2 and compressed air in an oxidizing environment. Nitrogen plasma treatment leads to the highest catalytical activities at the same operational conditions. Through a variation of the nitrogen plasma treatment duration a maximum performance at about 14 min cm-2 was observed, which is also represented by a minimum of 90 Ω in the charge transfer resistance obtained by EIS measurements. The morphology changes of the graphitized surface were followed using SEM.

  12. Greenhouse wastewater treatment by baffled subsurface-flow constructed wetlands supplemented with flower straws as carbon source in different modes. (United States)

    Chang, Junjun; Ma, Luyao; Chen, Jinquan; Lu, Yifeng; Wang, Xiaoyun


    Four laboratory-scale baffled subsurface-flow constructed wetlands (BSCWs) were established for the treatment of greenhouse wastewater containing high levels of nitrate and sulfate in the present study. Each BSCW microcosm involved a treatment zone and another post-treatment zone with a surface area ratio of 2:1. Evenly mixed straws of carnation and rose (w/w: 1/1), two common ornamental flowers, were supplemented as an organic carbon source into the treatment zone through a hydrolysis zone (CW 1), decentralized vertically installed perforated pipes (CW 2), and centralized pipes (CW 3 in the figures), except the blank system. Removals and transformations of nitrogen and sulfate as well as carbon release in the BSCWs were investigated and comparatively assessed. Results showed that the supplements of flower straws could greatly enhance both the nitrate and sulfate removals, and good performance was achieved during the beginning operation period of 30 days, followed by decline due to insufficient organic carbon supply. Nitrate removal efficiency was significantly higher and more stable compared to sulfate. The highest removal rates of nitrate and sulfate were achieved in the CW 3, with a mean value of 4.33 g NO 3 - -N·m -2  d -1 and 2.74 g SO 4 2- -S·m -2  d -1 , respectively, although the differences among the experimental microcosms were not statistically significant. However, almost the same TN removal rate (3.40-3.47 g N·m -2  d -1 ) was obtained due to the productions of NO 2 - -N and NH 4 + -N and leaching of organic N from the straws. High contents of organic carbon and colored substance were leached from the straws during the initial 10 days, but dropped rapidly to low levels, and could hardly determined after 30 days operation. The post-treatment zone could further eliminate various contaminants, but the capability was limited. Inorganic carbon (IC) concentration was detected to be a highly good indicator for the estimation of nitrate and

  13. Optimisation of energy flows and material flows at the waste processing plan Chemnitz. Cost reduction of the waste treatment by improving the climatic changes and by improving the flexibility of the waste processing plant for a commercialization of the output flows; Energie- und Stoffstromoptimierung an der Restabfallbehandlungsanlage Chemnitz. Behandlungskostensenkung bei Verbesserung der Klimaauswirkungen und der Anlagenflexibilitaet fuer eine Vermarktung der Outputstroeme

    Energy Technology Data Exchange (ETDEWEB)

    Gollub, Marcus [WasteTec GmbH, Wetzlar (Germany)


    The waste processing plant Chemnitz (Chemnitz, Federal Republic of Germany) operates in accordance with a mechanical-physical waste treatment. Mainly municipal household wastes from the territories of the AWVC association were utilized. The author of the contribution under consideration reports on an optimization of the energy flow and material flow at the waste processing plant Chemnitz under consideration of the cost reduction of the waste treatment by improving the climatic changes and by improving the flexibility of the waste processing plant for a commercialization of the output flows.

  14. Numerical analysis of friction factor for a fully developed turbulent flow using k–ε turbulence model with enhanced wall treatment

    Directory of Open Access Journals (Sweden)

    Muhammad Ahsan


    Full Text Available The aim of this study is to formulate a computational fluid dynamics (CFD model that can illustrate the fully turbulent flow in a pipe at higher Reynolds number. The flow of fluids in a pipe network is an important and widely studied problem in any engineering industry. It is always significant to see the development of a fluid flow and pressure drop in a pipe at higher Reynolds number. A finite volume method (FVM solver with k–ε turbulence model and enhanced wall treatment is used first time to investigate the flow of water at different velocities with higher Reynolds number in a 3D pipe. Numerical results have been presented to illustrate the effects of Reynolds number on turbulence intensity, average shear stress and friction factor. Friction factor is used to investigate the pressure drop along the length of the pipe. The contours of wall function are also presented to investigate the effect of enhanced wall treatment on a fluid flow. A maximum Reynolds number is also found for which the selected pipe length is sufficient to find a full developed turbulent flow at outlet. The results of CFD modeling are validated by comparing them with available data in literature. The model results have been shown good agreement with experimental and co-relation data.

  15. Effects of Change in Tongue Pressure and Salivary Flow Rate on Swallow Efficiency Following Chemoradiation Treatment for Head and Neck Cancer. (United States)

    Rogus-Pulia, Nicole M; Larson, Charles; Mittal, Bharat B; Pierce, Marge; Zecker, Steven; Kennelty, Korey; Kind, Amy; Connor, Nadine P


    Patients treated with chemoradiation for head and neck cancer frequently develop dysphagia. Tissue damage to the oral tongue causing weakness along with decreases in saliva production may contribute to dysphagia. Yet, effects of these variables on swallowing-related measures are unclear. The purpose of this study was (1) to determine effects of chemoradiation on tongue pressures, as a surrogate for strength, and salivary flow rates and (2) to elucidate relationships among tongue pressures, saliva production, and swallowing efficiency by bolus type. Twenty-one patients with head and neck cancer treated with chemoradiation were assessed before and after treatment and matched with 21 healthy control participants who did not receive chemoradiation. Each participant was given a questionnaire to rate dysphagia symptoms. Videofluoroscopic Evaluation of Swallowing (VFES) was used to determine swallowing efficiency; the Saxon test measured salivary flow rate; and the Iowa Oral Performance Instrument (IOPI) was used for oral tongue maximum and endurance measures. Results revealed significantly lower tongue endurance measures for patients post-treatment as compared to controls (p = .012). Salivary flow rates also were lower compared to pre-treatment (p = .000) and controls (p = .000). Simple linear regression analyses showed that change in salivary flow rate was predictive of change in swallow efficiency measures from pre- to post-treatment for 1 mL thin liquid (p = .017), 3 mL nectar-thick liquid (p = .026), and 3 mL standard barium pudding (p = .011) boluses. Based on these findings, it appears that chemoradiation treatment affects tongue endurance and salivary flow rate, and these changes may impact swallow efficiency. These factors should be considered when planning treatment for dysphagia.

  16. Tolerance of the antibiotic tylosin on treatment performance of an up-flow anaerobic stage reactor (UASR). (United States)

    Chelliapan, S; Wilby, T; Sallis, P J; Yuzir, A


    Tylosin has been considered inhibiting COD removal in anaerobic digestion. In this study it is proven that this is not always the case. Accordingly, elevated concentrations of Tylosin (100-800mgL-1) could be tolerated by the anaerobic system. The influence of Tylosin concentrations on an up-flow anaerobic stage reactor (UASR) was assessed using additions of Tylosin phosphate concentrate. Results showed high efficiency for COD removal (average 93%) when Tylosin was present at concentrations ranging from 0 to 400 mg L-1. However, at Tylosin concentrations of 600 and 800 mg L-1 treatment efficiency declined to 85% and 75% removal respectively. The impact of Tylosin concentrations on archaeal activity were investigated and the analysis revealed that archaeal cells dominated the reactor, confirming that there was no detectable inhibition of the methanogens at Tylosin levels between 100 and 400mg L-1. Nevertheless, the investigation showed a slight reduction in the number of methanogens at Tylosin levels of 600 and 800 mg L-1. These results demonstrated that the methanogens were well adapted to Tylosin. It would not be expected that the process performance of the UASR would be affected, not even at a level well in excess of those appearing in real wastewater from a Tylosin production site.

  17. Incorporation of oxygen contribution by plant roots into classical dissolved oxygen deficit model for a subsurface flow treatment wetland. (United States)

    Bezbaruah, Achintya N; Zhang, Tian C


    It has been long established that plants play major roles in a treatment wetland. However, the role of plants has not been incorporated into wetland models. This study tries to incorporate wetland plants into a biochemical oxygen demand (BOD) model so that the relative contributions of the aerobic and anaerobic processes to meeting BOD can be quantitatively determined. The classical dissolved oxygen (DO) deficit model has been modified to simulate the DO curve for a field subsurface flow constructed wetland (SFCW) treating municipal wastewater. Sensitivities of model parameters have been analyzed. Based on the model it is predicted that in the SFCW under study about 64% BOD are degraded through aerobic routes and 36% is degraded anaerobically. While not exhaustive, this preliminary work should serve as a pointer for further research in wetland model development and to determine the values of some of the parameters used in the modified DO deficit and associated BOD model. It should be noted that nitrogen cycle and effects of temperature have not been addressed in these models for simplicity of model formulation. This paper should be read with this caveat in mind.

  18. A novel flow diverter(Tubridge) for the treatment of recurrent aneurysms: A single-center experience

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yong Xin; Huang, Qing Hai; Fang, Yibin; Yang, Peng Fei; Xu, Yi; Hong Bo; Liu, Jian Min [Dept. of Neurosurgery, Changhai Hospital, Second Military Medical University, Shanghai (China)


    The Tubridge flow diverter (FD) is a novel device aimed at reconstructing the parent artery and occluding complex aneurysms. Retreatment of recurrent aneurysms using the FD is challenging. We report our initial experience in the repair of aneurysm recurrence with the FD. A database was reviewed prospectively, and 8 patients with 8 recurrent aneurysms (mean size, 16.7 mm) were identified. Four aneurysms had previously ruptured. The previous aneurysm treatment consisted of coiling in 1 aneurysm and single-stent-assisted coiling in 7 aneurysms. The procedural complications and clinical and angiographic outcomes were analyzed. Six aneurysms were treated by using a single Tubridge FD alone, while the remaining 2 were treated with FD + coiling. The immediate results of the 8 aneurysms were that they all showed incomplete occlusion. Neither major ischemic nor hemorrhagic complications occurred; however, 1 patient experienced a vasospasm. Follow-up angiographies were available for 7 aneurysms; the mean follow-up was 16.9 months (7–36 months). Five aneurysms were completely occluded, whereas 2 had a residual neck. Severe asymptomatic stenosis of 1 parent artery of a vertebral artery dissecting aneurysm was found. All visible branches covered by the FD were patent. All patients were clinically assessed as having attained a favorable outcome (modified Rankin Scale score ≤ 2) at discharge and follow-up. In selected patients, the Tubridge FD can provide a safe and efficient option for the retreatment of recurrent aneurysms. Nevertheless, attention should be paid to several technical points.

  19. Structural characterisation of pretreated solids from flow-through liquid hot water treatment of sugarcane bagasse in a fixed-bed reactor

    CSIR Research Space (South Africa)

    Reddy, P


    Full Text Available Untreated sugarcane bagasse and sugarcane bagasse pretreated with flow-through liquid hot water (LHW) treatment (170-207°C and 204-250 ml/min) in a fixed-bed reactor have been structurally characterised. Field emission gun scanning electron...

  20. The effect of hydraulic retention time on the removal of pollutants from sewage treatment plant effluent in a surface-flow wetland system

    NARCIS (Netherlands)

    Toet, Sylvia; Van Logtestijn, R. S P; Kampf, Ruud; Schreijer, Michiel; Verhoeven, J. T A

    We evaluated the effect of four hydraulic retention times (HRT, 0.3, 0.8, 2.3, and 9.3 days) on pollutant removal in a surface-flow wetland system for polishing tertiary effluent from a sewage treatment plant (STP). The removal efficiency of pollutants at these HRTs was based on mass budgets of the

  1. Microbial community composition of a down-flow hanging sponge (DHS) reactor combined with an up-flow anaerobic sludge blanket (UASB) reactor for the treatment of municipal sewage. (United States)

    Kubota, Kengo; Hayashi, Mikio; Matsunaga, Kengo; Iguchi, Akinori; Ohashi, Akiyoshi; Li, Yu-You; Yamaguchi, Takashi; Harada, Hideki


    The microbial community composition of a down-flow hanging sponge (DHS) reactor in an up-flow anaerobic sludge blanket (UASB)-DHS system used for the treatment of municipal sewage was investigated. The clone libraries showed marked differences in microbial community composition at different reactor heights and in different seasons. The dominant phylotypes residing in the upper part of the reactor were likely responsible for removing organic matters because a significant reduction in organic matter in the upper part was observed. Quantification of the amoA genes revealed that the proportions of ammonia oxidizing bacteria (AOB) varied along the vertical length of the reactor, with more AOB colonizing the middle and lower parts of the reactor than the top of the reactor. The findings indicated that sewage treatment was achieved by a separation of microbial habitats responsible for organic matter removal and nitrification in the DHS reactor. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Anti-vascular endothelial growth factor treatment induces blood flow recovery through vascular remodeling in high-fat diet induced diabetic mice. (United States)

    Xiao, Lamei; Yan, Kai; Yang, Yan; Chen, Ni; Li, Yongjie; Deng, Xin; Wang, Liqun; Liu, Yan; Mu, Lin; Li, Rong; Luo, Mao; Ren, Meiping; Wu, Jianbo


    Diabetes mellitus (DM) leads to the development of microvascular diseases and is associated with impaired angiogenesis. The presence of vascular endothelial growth factor (VEGF) can block PDGF-BB dependent regulation of neovascularization and vessel normalization. We tested the hypothesis that the inhibition of VEGF improves blood flow in a mouse hindlimb ischemia model produced by femoral artery ligation. In this study, we examined the effect of bevacizumab, a humanized monoclonal antibody against VEGF-A, on blood perfusion and angiogenesis after hindlimb ischemia. We showed that bevacizumab induces functional blood flow in high fat chow (HFC)-fed diabetic mice. Treatment with bevacizumab increased the expression of platelet derived growth factor-BB (PDGF-BB) in ischemic muscle, and led to vascular normalization. It also blocked vascular leakage by improving the recruitment of pericytes associated with nascent blood vessels, but it did not affect capillary formation. Furthermore, treatment with an anti-PDGF drug significantly inhibited blood flow perfusion in diabetic mice treated with bevacizumab. These results indicate that bevacizumab improves blood flow recovery through the induction of PDGF-BB in a diabetic mouse hindlimb ischemia model, and that vessel normalization may represent a useful strategy for the prevention and treatment of diabetic peripheral arterial disease. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. CVVHD treatment with CARPEDIEM: small solute clearance at different blood and dialysate flows with three different surface area filter configurations. (United States)

    Lorenzin, Anna; Garzotto, Francesco; Alghisi, Alberta; Neri, Mauro; Galeano, Dario; Aresu, Stefania; Pani, Antonello; Vidal, Enrico; Ricci, Zaccaroa; Murer, Luisa; Goldstein, Stuart L; Ronco, Claudio


    The CARdiorenal PEDIatric EMergency (CARPEDIEM) machine was originally designed to perform only continuous venovenous hemofiltration (CVVH) in neonatal and pediatric patients. In some cases, adequate convective clearance may not be reached because of a limited blood flow. In such conditions, the application of diffusive clearance [continuous venovenous hemodialysis (CVVHD)] would help optimize blood purification. In this study, the CARPEDIEM™ machine was modified to enable the circulation of dialysis through the filter allowing testing of the performance of CARPEDIEM™ machine in CVVHD. Three different polyethersulfone hemodialyzers (surface area = 0.1 m(2), 0.2 m(2), and 0.35 m(2), respectively) were tested in vitro with a scheduled combination of plasma flow rates (Qp = 10-20-30 ml/min) and dialysis fluid flow rate (Qd = 5-10-15 ml/min). Three sessions were performed in co-current and one in counter-current configuration (as control) for each filter size. Clearance was measured from the blood and dialysate sides and results with mass balance error greater than 5 % were discarded. Urea and creatinine clearances for each plasma/dialysate combination are reported: clearance increase progressively for every filter proportionally to plasma flow rates. Similarly, clearances increase progressively with dialysate flow rates at a given plasma flow. The clearance curve tends to present a steep increase for small increases in plasma flow in the range below 10 ml/min, while the curve tends to plateau for values averaging 30 ml/min. As expected, the plateau is reached earlier with the smaller filter showing the effect of membrane surface-area limitation. At every plasma flow, the effect of dialysate flow increase is evident and well defined, showing that saturation of effluent was not achieved completely in any of the experimental conditions explored. No differences (p > 0.05 for all values) were obtained in experiments using whole blood instead of

  4. Performance of up flow anaerobic sludge fixed film bioreactor for the treatment of high organic load and biogas production of cheese whey wastewater

    Directory of Open Access Journals (Sweden)

    Tehrani Nazila Samimi


    Full Text Available Among various wastewater treatment technologies, biological wastewater treatment appears to be the most promising method. A pilot scale of hybrid anaerobic bioreactor was fabricated and used for the whey wastewater treatment. The top and bottom of the hybrid bioreactor known as up flow anaerobic sludge fixed film (UASFF; was a combination of up flow anaerobic sludge blanket (UASB and up flow anaerobic fixed film reactor (UAFF, respectively. The effects of operating parameters such as temperature and hydraulic retention time (HRT on chemical oxygen demand (COD removal and biogas production in the hybrid bioreactor were investigated. Treatability of the samples at various HRTs of 12, 24, 36 and 48 hours was evaluated in the fabricated bioreactor. The desired conditions for COD removal such as HRT of 48 hours and operation temperature of 40 °C were obtained. The maximum COD removal and biogas production were 80% and 2.40 (L/d, respectively. Kinetic models of Riccati, Monod and Verhalst were also evaluated for the living microorganisms in the treatment process. Among the above models, Riccati model was the best growth model fitted with the experimental data with R2 of about 0.99.

  5. The modeling of contaminant flow during proposed treatment of U.S. Department of Energy low-level radioactive mixed wastes

    International Nuclear Information System (INIS)

    Dolak, D.A.; Wilkins, B.D.; Kotek, T.J.; Wang, Y.Y.; Meshkov, N.K.


    Estimations of waste materials throughput and the potential radiological and chemical releases resulting from the proposed treatment of US Department of Energy (DOE) low-level mixed wastes (LLMWs) were used to support analyses of risks and costs associated with various waste management alternatives outlined in the Office of Environmental Management Programmatic Environmental Impact Statement (EM PEIS). The modeling of material flow and contaminant releases through a consolidated waste management flowchart was performed by the WASTE MGMT computational model developed by Argonne National Laboratory. This paper (1) briefly describes the process used to model estimated material and contaminant flow through the proposed treatment scenarios for the EM PEIS, (2) discusses the key site- and/or waste-stream-dependent factors involved in the determination of radiological and chemical emissions, and (3) explains the assumptions used to integrate the available LLMW database with the computational model

  6. Performance evaluation of the sulfur-redox-reaction-activated up-flow anaerobic sludge blanket and down-flow hanging sponge anaerobic/anoxic sequencing batch reactor system for municipal sewage treatment. (United States)

    Hatamoto, Masashi; Ohtsuki, Kota; Maharjan, Namita; Ono, Shinya; Dehama, Kazuya; Sakamoto, Kenichi; Takahashi, Masanobu; Yamaguchi, Takashi


    A sulfur-redox-reaction-activated up-flow anaerobic sludge blanket (UASB) and down-flow hanging sponge (DHS) system, combined with an anaerobic/anoxic sequencing batch reactor (A2SBR), has been used for municipal sewage treatment for over 2 years. The present system achieved a removal rate of 95±14% for BOD, 74±22% for total nitrogen, and 78±25% for total phosphorus, including low water temperature conditions. Sludge conversion rates during the operational period were 0.016 and 0.218 g-VSS g-COD-removed(-1) for the UASB, and DHS, respectively, which are similar to a conventional UASB-DHS system, which is not used of sulfur-redox-reaction, for sewage treatment. Using the sulfur-redox reaction made advanced treatment of municipal wastewater with minimal sludge generation possible, even in winter. Furthermore, the occurrence of a unique phenomenon, known as the anaerobic sulfur oxidation reaction, was confirmed in the UASB reactor under the winter season. Copyright © 2016. Published by Elsevier Ltd.

  7. Structural characterisation of pretreated solids from flow-through liquid hot water treatment of sugarcane bagasse in a fixed-bed reactor. (United States)

    Reddy, Prashant; Lekha, Prabashni; Reynolds, Wienke; Kirsch, Christian


    Untreated sugarcane bagasse and sugarcane bagasse pretreated with flow-through liquid hot water (LHW) treatment (170-207°C and 204-250 ml/min) in a fixed-bed reactor have been structurally characterised. Field emission gun scanning electron microscopy (FEG-SEM) and transmission electron microscopy (TEM) were used to investigate changes in the residues, in particular due to the fate of lignin. FEG-SEM results show that the LHW treatment modified the surface morphology of the pretreated bagasse with lignin droplets being observed on the fibre surface. TEM showed an increase in the plant cell wall porosity and lignin migration across the plant cell wall. Increases in pretreatment temperature were observed to increase the average size and density of lignin droplets on the fibre surface. The results provide evidence that for LHW flow-through treatment, just as for batch treatment, lignin repolymerisation and deposition on the surface of pretreated sugarcane bagasse is an important consideration. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. The effect of statin treatment on the prevention of stent mediated flow limited edge dissections during PCI in patients with stable angina. (United States)

    Oksuz, Fatih; Yarlioglues, Mikail; Yayla, Cagrı; Canpolat, Ugur; Murat, Sani Namık; Aydogdu, Sinan


    The effect of statin therapy before PCI with direct stenting may reduce the development of flow limited edge dissections (ED) in patients with stable angina. Flow limited ED after PCI is associated with an increased risk of major adverse cardiovascular events. Statin therapy induces important changes in the plaque composition which have been previously identified as strong predictors of ED. 100 patients complicated with flow limited ED and 100 control patients with successful procedure were enrolled into the study. EDs were described as the 5-mm regions that were immediately adjacent to the stent borders, both distally and proximally on the coronary angiography. Rate of statin use and duration of statin use were significantly higher in patients with non-ED group (63%) versus ED group (25%) (p<0.001). In addition, patients in ED group had significantly higher levels of C-reactive protein (CRP) at admission (9.9mg/dL (5.89-16.45) vs. 4.40mg/dL (3.5-7.09), respectively, p=0.014). Our findings suggested that maintenance statin treatment before PCI with direct stenting may reduce the development of flow limited ED in patients with stable angina. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  9. Role of macrophyte and effect of supplementary aeration in up-flow constructed wetland-microbial fuel cell for simultaneous wastewater treatment and energy recovery. (United States)

    Oon, Yoong-Ling; Ong, Soon-An; Ho, Li-Ngee; Wong, Yee-Shian; Dahalan, Farrah Aini; Oon, Yoong-Sin; Lehl, Harvinder Kaur; Thung, Wei-Eng; Nordin, Noradiba


    This study investigates the role of plant (Elodea nuttallii) and effect of supplementary aeration on wastewater treatment and bioelectricity generation in an up-flow constructed wetland-microbial fuel cell (UFCW-MFC). Aeration rates were varied from 1900 to 0mL/min and a control reactor was operated without supplementary aeration. 600mL/min was the optimum aeration flow rate to achieve highest energy recovery as the oxygen was sufficient to use as terminal electron acceptor for electrical current generation. The maximum voltage output, power density, normalized energy recovery and Coulombic efficiency were 545.77±25mV, 184.75±7.50mW/m 3 , 204.49W/kg COD, 1.29W/m 3 and 10.28%, respectively. The variation of aeration flow rates influenced the NO 3 - and NH 4 + removal differently as nitrification and denitrification involved conflicting requirement. In terms of wastewater treatment performance, at 60mL/min aeration rate, UFCW-MFC achieved 50 and 81% of NO 3 - and NH 4 + removal, respectively. E. nuttallii enhanced nitrification by 17% and significantly contributed to bioelectricity generation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Comparison of simple, small, full-scale sewage treatment systems in Brazil: UASB-maturation ponds-coarse filter; UASB-horizontal subsurface-flow wetland; vertical-flow wetland (first stage of French system). (United States)

    von Sperling, M


    This paper presents a comparison between three simple sewage treatment lines involving natural processes: (a) upflow anaerobic sludge blanket (UASB) reactor-three maturation ponds in series-coarse rock filter; (b) UASB reactor-horizontal subsurface-flow constructed wetland; and (c) vertical-flow constructed wetlands treating raw sewage (first stage of the French system). The evaluation was based on several years of practical experience with three small full-scale plants receiving the same influent wastewater (population equivalents of 220, 60 and 100 inhabitants) in the city of Belo Horizonte, Brazil. The comparison included interpretation of concentrations and removal efficiencies based on monitoring data (organic matter, solids, nitrogen, phosphorus, coliforms and helminth eggs), together with an evaluation of practical aspects, such as land and volume requirements, sludge production and handling, plant management, clogging and others. Based on an integrated evaluation of all aspects involved, it is worth emphasizing that each system has its own specificities, and no generalization can be made on the best option. The overall conclusion is that the three lines are suitable for sewage treatment in small communities in warm-climate regions.

  11. A Case of Pseudoaneurysm of the Internal Carotid Artery Following Endoscopic Endonasal Pituitary Surgery: Endovascular Treatment with Flow-Diverting Stent Implantation

    Directory of Open Access Journals (Sweden)

    Ali Karadag


    Full Text Available Internal carotid artery (ICA pseudoaneurysm is a rare complication of endoscopic endonasal surgery occurring in 0.4–1.1% of cases. Pseudoaneurysms can subsequently result in other complications, such as subarachnoid hemorrhage, epistaxis, and caroticocavernous fistula with resultant death or permanent neurologic deficit. In this case, we illustrate endovascular treatment with a flow-diverting stent for an ICA pseudoaneurysm after endoscopic endonasal surgery for a pituitary adenoma in a 56-year-old male. Surgery was complicated by excessive intraoperative bleeding and emergent CT angiography confirmed an iatrogenic pseudoaneurysm on the anteromedial surface of the ICA. The pseudoaneurysm was treated endovascularly with flow-diverting stent implantation only. Follow-up CT angiography after three months demonstrated occlusion of the pseudoaneurysm.

  12. Evaluation of occurring complications after flow diverter treatment of elastase-induced aneurysm in rabbits using micro-CT and MRI at 9.4 T

    Energy Technology Data Exchange (ETDEWEB)

    Simgen, Andreas; Ley, Desiree; Muehl-Benninghaus, Ruben; Koerner, Heiko; Reith, Wolfgang; Yilmaz, Umut [Saarland University Hospital, Department of Neuroradiology, Homburg, Saar (Germany); Roth, Christian [Clinic Bremen-Mitte, Department of Neuroradiology, Bremen (Germany); Cattaneo, Giorgio Franco Maria [Acandis GmbH, Pforzheim (Germany); Mueller, Andreas [Saarland University Hospital, Department of Experimental Surgery, Homburg, Saar (Germany); Kim, Yoo-Jin [Saarland University Hospital, Department of Pathology, Homburg, Saar (Germany); Scheller, Bruno [Saarland University Hospital, Department of Cardiology, Homburg, Saar (Germany)


    Flow diverters are increasingly being used to treat intracranial aneurysms. This study evaluates occurring complications of flow-diverting devices in the treatment of experimental aneurysms, involving the use of micro-CT and small animal MRI at 9.4 T, in correlation to angiographic and histological findings. We previously published two preclinical studies, in which we assessed two different flow diverters in the treatment of elastase-induced aneurysms. Devices have been implanted across the aneurysm neck as well as in the abdominal aorta. From these studies, a total of 65 devices (prototype FD (n = 30) and Derivo embolization device (n = 35)) additionally underwent micro-CT and MRI after angiographic follow-up and before being histologically examined. The different architectures of both devices were precisely comparable due to high-resolution micro-CT imaging. Micro-CT revealed wire fractures in nine cases (30 %) only with the prototype FD. In three cases (10 %), severe wire fractures correlated with an in-stent stenosis due to intimal hyperplasia. Other complications, like distal stent occlusions and post-stent stenosis, were seen in both groups and verified with both imaging techniques. Osseous metaplasia were correlated to calcifications seen with micro-CT. MRI enabled visualization of the position of the implanted devices relative to the aneurysm and revealed incomplete aneurysm neck coverage with the prototype FD in two cases (6.7 %). Micro-CT and 9.4-T MRI are valid to discover and understand occurring complications of flow diverters in the preclinical phase and can serve as evaluation tools to minimize complication rates of endovascular devices in the future. (orig.)

  13. The Response of Nitrifying Bacteria to Treatments of N-Serve and Roundup in Continuous-Flow Soil Columns (United States)


    In soil columns (Prosser and Gray, 1977) it was shown, though, that Nitrobacter was present in the effluent at 2.4xiO cells -i -1 ml where...decreased the lag phase of Nitrobacter in pure culture. McCarty and Bremner (1986b), however, have shown that phenolic compounds and tannins , representative...flow methods are- plotted versus time. Data represents concentrations of nitrate in extracts or effluents compiled from controls from each of the

  14. Interdependences between flow patterns and oxygen entry in aeration tanks of wastewater treatment plants; Der Zusammenhang von Stroemungsstrukturen und Sauerstoffeintrag bei druckbeluefteten Belebungsbecken

    Energy Technology Data Exchange (ETDEWEB)

    Thiersch, B.


    The flow field, turbulence intensities and the distribution of the relative gas-holdup of aeration tanks of operating wastewater treatment plants were investigated experimentally with Acoustic-Doppler-Velocimeter probes. Based on the experimental results a hydrodynamical model in Euler-Euler-Formulation was developed and numerical studies of different tank and diffuser arrangements were performed. It was found that the flow pattern is mainly influenced by the gas sparger arrangement and the tank aspect-ratio. Combining the experimental and numerical results reasons for different aeration efficiencies were identified. Increasing the diffuser density changed the flow field from the spiral type to the cellular pattern with instable and dynamical structures. These flow patterns improved the aeration efficiency by increasing the residence time of the bubbles and the recirculating flows. (orig.) [German] In der vorliegenden Arbeit werden grundlegende Stroemungsstrukturen von druckbeluefteten Belebungsbecken anhand messtechnischer Untersuchungen der Geschwindigkeitsverteilungen, Turbulenzgroessen und relativer Gasgehaltsverteilungen von Belebungsbecken im Betriebszustand aufgezeigt. Vorab wird die Einsatzfaehigkeit von Akkustik-Doppler-Sonden in dispersen Zweiphasenstroemungen detailliert ueberprueft. Aufbauend auf den Messergebnissen wird ein numerisches Simulationsprogramm zur dynamischen Berechnung unterschiedlicher Beckenkonfigurationen entwickelt. Aus den experimentellen Ergebnissen in Verbindung mit den Berechnungsergebnissen sowie den Auswertungen frueherer Untersuchungen konnten hydromechanische Ursachen der unterschiedlichen Sauerstoffeintragseffizienz bei verschiedenen Beckenkonzeptionen abgeleitet werden. Dabei stellen die Anordnung sowie Gleichverteilung der Belueftungselemente sowie das Querschnittsverhaeltnis der Belebungsbecken die wesentlichen Einflussgroessen auf die Ausbildung der Stroemungsstrukturen dar. Mit zunehmender Belegungsdichte und

  15. The effect of flow modes and electrode combinations on the performance of a multiple module microbial fuel cell installed at wastewater treatment plant

    KAUST Repository

    He, Weihua


    A larger (6.1 L) MFC stack made in a scalable configuration was constructed with four anode modules and three (two-sided) cathode modules, and tested at a wastewater treatment plant for performance in terms of chemical oxygen demand (COD) removal and power generation. Domestic wastewater was fed either in parallel (raw wastewater to each individual anode module) or series (sequentially through the chambers), with the flow direction either alternated every one or two days or kept fixed in a single direction over time. The largest impact on performance was the wastewater COD concentration, which greatly impacted power production, but did not affect the percentage of COD removal. With higher COD concentrations (∼500 mg L−1) and alternating flow conditions, power generation was primarily limited by the cathode specific area. In alternating flow operation, anode modules connected to two cathodes produced an average maximum power density of 6.0 ± 0.4 W m−3, which was 1.9 ± 0.2 times that obtained for anodes connected to a single cathode. In fixed flow operation, a large subsequent decrease in COD influent concentration greatly reduced power production independent of reactor operation in parallel or serial flow modes. Anode modules connected to two cathodes did not consistently produce more power than the anodes connected to a single cathode, indicating power production became limited by restricted anode performance at low CODs. Cyclic voltammetry and electrochemical impedance spectroscopy data supported restricted anode performance with low COD. These results demonstrate that maintaining power production of MFC stack requires higher influent and effluent COD concentrations. However, overall performance of the MFC in terms of COD removal was not affected by operational modes.

  16. Continuous-flow ultrasound assisted oxidative desulfurization (UAOD) process: An efficient diesel treatment by injection of the aqueous phase. (United States)

    Rahimi, Masoud; Shahhosseini, Shahrokh; Movahedirad, Salman


    A new continuous-flow ultrasound assisted oxidative desulfurization (UAOD) process was developed in order to decrease energy and aqueous phase consumption. In this process the aqueous phase is injected below the horn tip leading to enhanced mixing of the phases. Diesel fuel as the oil phase with sulfur content of 1550ppmw and an appropriate mixture of hydrogen peroxide and formic acid as the aqueous phase were used. At the first step, the optimized condition for the sulfur removal has been obtained in the batch mode operation. Hence, the effect of more important oxidation parameters; oxidant-to-sulfur molar ratio, acid-to-sulfur molar ratio and sonication time were investigated. Then the optimized conditions were obtained using Response Surface Methodology (RSM) technique. Afterwards, some experiments corresponding to the best batch condition and also with objective of minimizing the residence time and aqueous phase to fuel volume ratio have been conducted in a newly designed double-compartment reactor with injection of the aqueous phase to evaluate the process in a continuous flow operation. In addition, the effect of nozzle diameter has been examined. Significant improvement on the sulfur removal was observed specially in lower sonication time in the case of dispersion method in comparison with the conventional contact between two phases. Ultimately, the flow pattern induced by ultrasonic device, and also injection of the aqueous phase were analyzed quantitatively and qualitatively by capturing the sequential images. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Assessment of a Danish sludge treatment reed bed system and a stockpile area, using substance flow analysis

    DEFF Research Database (Denmark)

    Larsen, Julie Dam; Nielsen, Steen M; Scheutz, Charlotte


    of substances in an STRB system over a 12-year treatment period, followed by three months' post-treatment in a stockpile area (SPA). Samples of sludge, reject water and sludge residue of different ages were collected at two Danish STRB system facilities and analysed for content of relevant substances....... Concentrations of carbon and nitrogen in the sludge residue residing in an STRB system changed as a function of treatment time, mainly due to mineralisation; only a negligible part was lost to reject water. Considering metals and phosphorus, the main share was accumulated in the sludge residue; only minor...... fractions were lost to mineralisation or reject water. Post-treatment in an SPA resulted in an increase in dry matter content from 24% to 32%. After treatment, the concentrations of heavy metals (lead, cadmium, nickel, zinc, copper and chromium) in the sludge residue met the threshold values stated...

  18. High flux MWCNTs-interlinked GO hybrid membranes survived in cross-flow filtration for the treatment of strontium-containing wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Lin; Lu, Ying [Key Laboratory of Biomass Chemical Engineering, Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027 (China); Liu, Ying-Ling [Department of Chemical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Li, Ming [Xi' an High-Tech Institute, Xi' an 710025 (China); Zhao, Hai-Yang [Key Laboratory of Biomass Chemical Engineering, Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027 (China); Hou, Li-An, E-mail: [Key Laboratory of Biomass Chemical Engineering, Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027 (China); Xi' an High-Tech Institute, Xi' an 710025 (China)


    Graphene oxide (GO)-based membranes provide an encouraging opportunity to support high separation efficiency for wastewater treatment. However, due to the relatively weak interaction between GO nanosheets, it is difficult for bare GO-based membranes to survive in cross-flow filtration. In addition, the permeation flux of the bare GO membrane is not high sufficiently due to its narrow interlayer spacing. In this study, GO membranes interlinked with multi-walled carbon nanotubes (MWCNTs) via covalent bonds were fabricated on modified polyacrylonitrile (PAN) supports by vacuum filtration. Due to the strong bonds between GO, MWCNTs and the PAN membrane, the membranes could be used for the treatment of simulated nuclear wastewater containing strontium via a cross-flow process. The result showed a high flux of 210.7 L/(m{sup 2} h) at 0.4 MPa, which was approximately 4 times higher than that of commercial nanofiltration membranes. The improved water permeation was attributed to the nanochannels created by the interlinked MWCNTs in the GO layers. In addition, the hybrid membrane exhibited a high rejection of 93.4% for EDTA-chelated Sr{sup 2+} in an alkaline solution, and could also be used to separate Na{sup +}/Sr{sup 2+} mixtures. These results indicate that the MWCNTs-interlinked GO membrane has promising prospects for application in radioactive waste treatment.

  19. Early captopril treatment inhibits DNA synthesis in endothelial cells and normalization of maximal coronary flow in infarcted rat hearts

    NARCIS (Netherlands)

    Nelissen-Vrancken, H. J.; Kuizinga, M. C.; Daemen, M. J.; Smits, J. F.


    Cardiac remodeling due to myocardial infarction (MI) includes myocyte hypertrophy, collagen deposition, a rise in DNA synthesis, and normalization of initially diminished maximal coronary bloodflow. Previously, we demonstrated that early captopril treatment can prevent the rise in total DNA

  20. Exact Analytical Solution of the Peristaltic Nanofluids Flow in an Asymmetric Channel with Flexible Walls and Slip Condition: Application to the Cancer Treatment

    Directory of Open Access Journals (Sweden)

    Abdelhalim Ebaid


    Full Text Available In the cancer treatment, magnetic nanoparticles are injected into the blood vessel nearest to the cancer’s tissues. The dynamic of these nanoparticles occurs under the action of the peristaltic waves generated on the flexible walls of the blood vessel. Studying such nanofluid flow under this action is therefore useful in treating tissues of the cancer. In this paper, the mathematical model describing the slip peristaltic flow of nanofluid was analytically investigated. Exact expressions were deduced for the temperature distribution and nano-particle concentration. In addition, the effects of the slip, thermophoresis, and Brownian motion parameters on the temperature and nano-particle concentration profiles were discussed and further compared with other approximate results in the literatures. In particular, these results have been obtained at the same values of the physical examined parameters that was considered in Akbar et al., “Peristaltic flow of a nanofluid with slip effects,” 2012. The results reveal that remarkable differences are detected between the exact current results and those approximately obtained in the literatures for behaviour of the temperature profile and nano-particles concentration. Accordingly, the current analysis and results are considered as optimal and therefore may be taken as a base for any future comparisons.

  1. Optimization of operating parameters of hybrid vertical down-flow constructed wetland systems for domestic sewerage treatment. (United States)

    Huang, Zhujian; Zhang, Xianning; Cui, Lihua; Yu, Guangwei


    In this work, three hybrid vertical down-flow constructed wetland (HVDF-CW) systems with different compound substrates were fed with domestic sewage and their pollutants removal performance under different hydraulic loading and step-feeding ratio was investigated. The results showed that the hydraulic loading and step-feeding ratio were two crucial factors determining the removal efficiency of most pollutants, while substrate types only significantly affected the removal of COD and NH4(+)-N. Generally, the lower the hydraulic loading, the better removal efficiency of all contaminants, except for TN. By contrast, the increase of step-feeding ratio would slightly reduce the removal rate of ammonium and TP but obviously promoted the TN removal. Therefore, the optimal operation of this CWs could be achieved with low hydraulic loading combined with 50% of step-feeding ratio when TN removal is the priority, whereas medium or low hydraulic loading without step-feeding would be suitable when TN removal is not taken into consideration. The obtained results in this study can provide us with a guideline for design and optimization of hybrid vertical flow constructed wetland systems to improve the pollutants removal from domestic sewage. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Use of Interface Treatment to Reduce Emissions from Residuals in Lower Permeability Zones to Groundwater flowing Through More Permeable Zones (Invited) (United States)

    Johnson, P.; Cavanagh, B.; Clifton, L.; Daniels, E.; Dahlen, P.


    Many soil and groundwater remediation technologies rely on fluid flow for contaminant extraction or reactant delivery (e.g., soil vapor extraction, pump and treat, in situ chemical oxidation, air sparging, enhanced bioremediation). Given that most unconsolidated and consolidated settings have permeability contrasts, the outcome is often preferential treatment of more permeable zones and ineffective treatment of the lower permeability zones. When this happens, post-treatment contaminant emissions from low permeability zone residuals can cause unacceptable long-term impacts to groundwater in the transmissive zones. As complete remediation of the impacted lower permeability zones may not be practicable with conventional technologies, one might explore options that lead to reduction of the contaminant emissions to acceptable levels, rather than full remediation of the lower permeability layers. This could be accomplished either by creating a sustained emission reaction/attenuation zone at the high-low permeability interface, or by creating a clean soil zone extending sufficiently far into the lower permeability layer to cause the necessary reduction in contaminant concentration gradient and diffusive emission. These options are explored in proof-of-concept laboratory-scale physical model experiments. The physical models are prepared with two layers of contrasting permeability and either dissolved matrix storage or nonaqueous phase liquid (NAPL) in the lower permeability layer. A dissolved oxidant is then delivered to the interface via flow across the higher permeability layer and changes in contaminant emissions from the low permeability zone are monitored before, during, and after oxidant delivery. The use of three oxidants (dissolved oxygen, hydrogen peroxide and sodium persulfate) for treatment of emissions from petroleum hydrocarbon residuals is examined.

  3. Evaluation of the process performance of a down-flow hanging sponge reactor for direct treatment of domestic wastewater in Bangkok, Thailand. (United States)

    Miyaoka, Yuma; Yoochatchaval, Wilasinee; Sumino, Haruhiko; Banjongproo, Pathan; Yamaguchi, Takashi; Onodera, Takashi; Okadera, Tomohiro; Syutsubo, Kazuaki


    This study assesses the performance of an aerobic trickling filter, down-flow hanging sponge (DHS) reactor, as a decentralized domestic wastewater treatment technology. Also, the characteristic eukaryotic community structure in DHS reactor was investigated. Long-term operation of a DHS reactor for direct treatment of domestic wastewater (COD = 150-170 mg/L and BOD = 60-90 mg/L) was performed under the average ambient temperature ranged from 28°C to 31°C in Bangkok, Thailand. Throughout the evaluation period of 550 days, the DHS reactor at a hydraulic retention time of 3 h showed better performance than the existing oxidation ditch process in the removal of organic carbon (COD removal rate = 80-83% and BOD removal rate = 91%), nitrogen compounds (total nitrogen removal rate = 45-51% and NH 4 + -N removal rate = 95-98%), and low excess sludge production (0.04 gTS/gCOD removed). The clone library based on the 18S ribosomal ribonucleic acid gene sequence revealed that phylogenetic diversity of 18S rRNA gene in the DHS reactor was higher than that of the present oxidation ditch process. Furthermore, the DHS reactor also demonstrated sufficient COD and NH 4 + -N removal efficiency under flow rate fluctuation conditions that simulates a small-scale treatment facility. The results show that a DHS reactor could be applied as a decentralized domestic wastewater treatment technology in tropical regions such as Bangkok, Thailand.

  4. [Comparison of curative effect of low flow rate plasma exchange combined with hemofiltration for treatment of liver failure]. (United States)

    Yang, Yong-feng; Huang, Ping; Zhang, Ning; Gai, Xiao-dong; Feng, Xiao-ning; Zhong, Yan-dan; Wang, Li-rong; Yang, Yi-jun; Zhao, Wei


    To investigate the effect of plasma exchange (PE) combined with hemofiltration (HF) on liver failure. Seventy-seven inpatients with liver failure admitted during January 2006 to August 2007 were randomly assigned to receive PE combined with HF (PE+HF group, 38 cases), or PE alone (PE group, 39 cases). Forty-one inpatients with liver failure who had not received artificial liver support treatment were assigned to serve as control group. The survival rates and biochemical parameters of three groups were compared. There was no significant difference in biochemical parameters before treatment among three groups. Compared with pre-treatment values, albumin (Alb), cholinesterase (ChE) and prothrombin activity (PTA) of both PE group and PE+HF group were significantly increased after treatment, and total bilirubin (TBIL), alanine transaminase (ALT), aspartate transaminase (AST) of both PE group and PE+HF group were significantly decreased after treatment (Prate of PE group, PE+HF group and control group was 48.7% (19/39), 68.4% (26/38), and 29.3% (12/41) respectively. The survival rate of PE+HF group was significantly higher than that of control group (chi(2)=12.11, Prate of recovery of consciousness of patients with hepatic encephalopathy in PE+HF group was higher than that of PE group (42.8% vs. 0, P<0.05). Compared with PE alone, the result was better when it was combined with HF in correction of electrolyte disturbance and acid-base imbalance (19/23 vs. 0/21, P<0.05). Treatment of liver failure by PE combined with HF is safe and effective, and its efficacy is higher than PE alone.

  5. Acupuncture Treatment for Low Back Pain and Lower Limb Symptoms—The Relation between Acupuncture or Electroacupuncture Stimulation and Sciatic Nerve Blood Flow

    Directory of Open Access Journals (Sweden)

    Motohiro Inoue


    Full Text Available To investigate the clinical efficacy of acupuncture treatment for lumbar spinal canal stenosis and herniated lumbar disc and to clarify the mechanisms in an animal experiment that evaluated acupuncture on sciatic nerve blood flow. In the clinical trial, patients with lumbar spinal canal stenosis or herniated lumbar disc were divided into three treatment groups; (i Ex-B2 (at the disordered level, (ii electrical acupuncture (EA on the pudendal nerve and (iii EA at the nerve root. Primary outcome measurements were pain and dysesthesia [evaluated with a visual analogue scale (VAS] and continuous walking distance. In the animal study, sciatic nerve blood flow was measured with laser-Doppler flowmetry at, before and during three kinds of stimulation (manual acupuncture on lumber muscle, electrical stimulation on the pudendal nerve and electrical stimulation on the sciatic nerve in anesthetized rats. For the clinical trial, approximately half of the patients who received Ex-B2 revealed amelioration of the symptoms. EA on the pudendal nerve was effective for the symptoms which had not improved by Ex-B2. Considerable immediate and sustained relief was observed in patients who received EA at the nerve root. For the animal study, increase in sciatic nerve blood flow was observed in 56.9% of the trial with lumber muscle acupuncture, 100% with pudendal nerve stimulation and 100% with sciatic nerve stimulation. Sciatic nerve stimulation sustained the increase longer than pudendal nerve stimulation. One mechanism of action of acupuncture and electrical acupuncture stimulation could be that, in addition to its influence on the pain inhibitory system, it participates in causing a transient change in sciatic nerve blood blow, including circulation to the cauda equine and nerve root.

  6. Application of vertical flow constructed wetland in treatment of heavy metals from pulp and paper industry wastewater. (United States)

    Arivoli, A; Mohanraj, R; Seenivasan, R


    The paper production is material intensive and generates enormous quantity of wastewater containing organic pollutants and heavy metals. Present study demonstrates the feasibility of constructed wetlands (CWs) to treat the heavy metals from pulp and paper industry effluent by using vertical flow constructed wetlands planted with commonly available macrophytes such as Typha angustifolia, Erianthus arundinaceus, and Phragmites australis. Results indicate that the removal efficiencies of the planted CWs for iron, copper, manganese, zinc, nickel, and cadmium were 74, 80, 60, 70, 71, and 70 %, respectively. On the other hand, the removal efficiency of the unplanted system was significantly lower ranging between 31 and 55 %. Among the macrophytes, T. angustifolia and E. arundinaceus exhibited comparatively higher bioconcentration factor (10(2) to 10(3)) than P. australis.

  7. Numerical simulation of heat transfer and fluid flow in a DC plasma-arc device for waste thermal treatment

    International Nuclear Information System (INIS)

    Deng, Jing; Li, Yaojian; Xu, Yongxiang; Sheng, Hongzhi


    In this work, Magnetic Fluid dynamics (MHD) model is used to stimulate the electromagnetic field, heat transfer and fluid flow in a DC non-transferred arc plasma torch. Through the coupled iterative computation about the electromagnetic equations described by magnetic vector potential format and the modified fluid dynamics equations, the electric potential, temperature and velocity distributions in the torch are obtained. The fluid-solid coupled computation method is applied to treat the electric current and heat transfer at the interface between the electrodes and fluid. The location of arc root attachment at the inside surface of anode and the arc voltage of the torch that we have predicted are very consistent with the corresponding experimental results. The calculated results of the torch are applied to the numerical simulation of the plasma jets under the laminar and turbulent condition. (author)

  8. The role of each compartment in a two-compartment vertical flow reactor for ferruginous mine water treatment. (United States)

    Yim, G J; Cheong, Y W; Hong, J H; Hur, W


    A vertical flow reactor (VFR) has been suggested for remediation of ferruginous mine drainage that passes down through an accreting bed of ochre. However, a VFR has a limited operation time until the system begins to overflow. In this study, a mathematical model was developed as a part of the effort to explore the operation of a VFR, showing dynamic changes in the head differences, ochre depths, and Fe(II)/Fe(III) concentrations in the effluent flow. The analysis showed that VFR operation time extended from 148.5 days to 163 days in an equally divided and to 168.4 days in asymmetrically (0.72:0.28) divided two-compartment VFR, suggesting that an optimum compartment ratio exists that maximizes the VFR operation time. A constant head filtration in the first compartment maximized filtration efficiency and thus prolonged VFR longevity in the two-compartment VFR. Fe(II) oxidation and ochre formation should be balanced with the permeability of the ochre bed to maximize the VFR operation time and minimize the residual Fe(II) in the effluent. Accelerated Fe(II) oxidation affected the optimum ratio of the compartment area and reduced the residual Fe(II) in the effluent. The VFR operation time can be prolonged significantly from 764 days to 3620 days by increasing the rate of ochre formation, much more than by accelerating the Fe(II) oxidation. During the prolonged VFR operation, ochre formed largely in the first compartment, while overflowing mine water with reduced iron content was effectively filtered in the second compartment. These results not only provide a better understanding of VFR operation but also suggest the direction of evolution of two-compartment VFR toward a compact and highly efficient facility integrated with an aerated cascade and with automatic coagulant feeding. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Impact of treatment on resting cerebral blood flow and metabolism in obsessive compulsive disorder: a meta-analysis

    NARCIS (Netherlands)

    van der Straten, A. L.; Denys, D.; van Wingen, G. A.


    Neurobiological models of obsessive-compulsive disorder (OCD) posit that its clinical symptoms such as repetitive thoughts and behaviors are related to hyperactivity in the cortico-striato-thalamo-cortical (CSTC) circuit. Small scale neuroimaging studies have shown that treatment of OCD is

  10. Sulfur flow in a soil-plant system-effects of long-term treatment history and soil properties

    DEFF Research Database (Denmark)

    Boye, Kristin; Eriksen, Jørgen; Nilsson, Ingvar


    deficiency, reduced biomass production and lower total S uptake by the rye grass. The isotopic measurements revealed that more than two thirds of the plant S was derived from non-labeled soil organic S, even in the + S treatment, and that all organic S pools (physically unprotected/protected and residual...

  11. Redox potential dynamics in a horizontal subsurface flow constructed wetland for wastewater treatment: Diel, seasonal ans spatial fluctuations

    Czech Academy of Sciences Publication Activity Database

    Dušek, Jiří; Picek, T.; Čížková, Hana


    Roč. 34, - (2008), s. 223-232 ISSN 0925-8574 Institutional research plan: CEZ:AV0Z60870520 Keywords : Redox potential * Redox prosesses * Phragmites australis * Wastewater treatment s * Constructed wetlands * Contunuous measurement Subject RIV: DJ - Water Pollution ; Quality Impact factor: 1.836, year: 2008

  12. Nitrogen removal and nitrous oxide emission in surface flow constructed wetlands for treating sewage treatment plant effluent: Effect of C/N ratios. (United States)

    Li, Ming; Wu, Haiming; Zhang, Jian; Ngo, Huu Hao; Guo, Wenshan; Kong, Qiang


    In order to design treatment wetlands with maximal nitrogen removal and minimal nitrous oxide (N 2 O) emission, the effect of influent C/N ratios on nitrogen removal and N 2 O emission in surface flow constructed wetlands (SF CWs) for sewage treatment plant effluent treatment was investigated in this study. The results showed that nitrogen removal and N 2 O emission in CWs were significantly affected by C/N ratio of influent. Much higher removal efficiency of NH 4 + -N (98%) and TN (90%) was obtained simultaneously in SF CWs at C/N ratios of 12:1, and low N 2 O emission (8.2mg/m 2 /d) and the percentage of N 2 O-N emission in TN removal (1.44%) were also observed. These results obtained in this study would be utilized to determine how N 2 O fluxes respond to variations in C/N ratios and to improve the sustainability of CWs for wastewater treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Recycling systems and material flows from the viewpoint of thermal waste treatment; Kreislaufwirtschaft- und Stoffstrombetrachtungen aus Sicht der thermischen Abfallbehandlung

    Energy Technology Data Exchange (ETDEWEB)

    Johnke, B. [Umweltbundesamt, Berlin (Germany); Mast, P.G. [Tauw Umwelt GmbH, Berlin (Germany)


    Material stream analysis can serve as a basis for decisions on which materials should be kept in circulation, and in what quantity, and which materials it is better to remove from the recycling system and dispose of as waste. Wastes destined for disposal are mostly transferred to waste treatment plants and landfills. The role of thermal treatment as part of the disposal system is to destroy or decompose organic pollutants contained in the waste, concentrate and remove inorganic pollutants, make the heat arising during the treatment process available for use as energy, and make the greatest possible physical use of the treatment residues. The present paper reviews the current regulations for the promotion of recycling and investigates selected material streams and the fate of these materials. In connection with the residue quality of household waste incineration slag as a thermal waste treatment product it also considers the influence of waste management measures on wastes destined for disposal. [Deutsch] Stoffstrombetrachtungen koennen als Grundlage fuer Entscheidungen dienen, welche Stoffe in welchem Umfang im Kreislauf verbleiben oder wieder integriert werden sollten und welche besser als Abfall zur Beseitigung aus dem Kreislaufsystem auszuschleusen sind. Fuer Abfaelle zur Beseitigung wird diese Aufgabe i.d.R. von thermischen Abfallbehandlungsanlagen und Deponien uebernommen. Im Rahmen der Entsorgung kommt der thermischen Behandlung dabei die Aufgabe zu, die im Abfall zur Beseitigung enthaltenen organischen Schadstoffe zu zerstoeren oder abzubauen, anorganische Schadstoffe aufzukonzentrieren und auszuschleusen, die bei dem Behandlungsprozess entstehende Waerme einer weitgehenden Energienutzung zuzufuehren und die Rueckstaende aus der Behandlung so weit wie moeglich stofflich zu verwerten. Nachfolgend sollen insbesondere die Regelungen zur Unterstuetzung der Kreislaufwirtschaft, ausgewaehlte Stofffluesse und der Verbleib dieser Stoffe und Materialien und der

  14. Flow Rounding


    Kang, Donggu; Payor, James


    We consider flow rounding: finding an integral flow from a fractional flow. Costed flow rounding asks that we find an integral flow with no worse cost. Randomized flow rounding requires we randomly find an integral flow such that the expected flow along each edge matches the fractional flow. Both problems are reduced to cycle canceling, for which we develop an $O(m \\log(n^2/m))$ algorithm.

  15. Evaluation of coronary blood flow reserve by {sup 13}N-NH{sub 3} positron emission computed tomography (PET) with dipyridamole in the treatment of hypertension with the ACE inhibitor (Cilazapril)

    Energy Technology Data Exchange (ETDEWEB)

    Masuda, Daisuke; Nohara, Ryuji [Kyoto Univ. (Japan). Graduate School of Medicine; Tamaki, Nagara (and others)


    The purpose of this study was to evaluate the effect of treatment with an angiotensin-converting enzyme (ACE) inhibitor (Cilazapril) for early hypertensive patients in terms of coronary blood flow reserve evaluated by {sup 13}NH{sub 3}-positron emission tomography (PET). Before and after 12 weeks of ACE inhibitor treatment, {sup 13}NH{sub 3}-PET with dipyridamole provocation test was performed, and definite myocardial perfusion and coronary flow reserve (CFR) were calculated. Compared to our normal subjects previously reported (2.61{+-}0.74), average coronary flow reserve was decreased (1.70{+-}0.64 in hypertensive patients), and improved after treatment (1.77{+-}0.52), but not significantly. Of 12 patients, five (42%) showed improved coronary flow reserve from 1.34 to 1.99 without a significant change in the resting flow. Only one patient (8%) showed deterioration after the ACE inhibitor treatment. The coronary vascular resistance (CVR) after ACE inhibitor treatment of the patients with CFR <2.0 decreased significantly compared with those with CFR {>=}2.0 (p<0.03). These results indicate that hypertensive patients at the early stage show decreased coronary flow reserve despite having normal resting flow. Treatment with an ACE inhibitor (Cilazapril) for 12 weeks improved coronary flow reserve in 42% of our patients. The CVR of the patients with CFR <2.0 showed improvement compared to those with CFR {>=}2.0. This result indicates that an ACE inhibitor (e.g., Cilazapril) should be one of the choices for improving CFR if hypertensive patients in early stage show signs of ischemia or diastolic dysfunction, which may be one of the sequels of reserve restriction. (author)

  16. Evaluation of coronary blood flow reserve by 13N-NH3 positron emission computed tomography (PET) with dipyridamole in the treatment of hypertension with the ACE inhibitor (Cilazapril)

    International Nuclear Information System (INIS)

    Masuda, Daisuke; Nohara, Ryuji; Tamaki, Nagara


    The purpose of this study was to evaluate the effect of treatment with an angiotensin-converting enzyme (ACE) inhibitor (Cilazapril) for early hypertensive patients in terms of coronary blood flow reserve evaluated by 13 NH 3 -positron emission tomography (PET). Before and after 12 weeks of ACE inhibitor treatment, 13 NH 3 -PET with dipyridamole provocation test was performed, and definite myocardial perfusion and coronary flow reserve (CFR) were calculated. Compared to our normal subjects previously reported (2.61±0.74), average coronary flow reserve was decreased (1.70±0.64 in hypertensive patients), and improved after treatment (1.77±0.52), but not significantly. Of 12 patients, five (42%) showed improved coronary flow reserve from 1.34 to 1.99 without a significant change in the resting flow. Only one patient (8%) showed deterioration after the ACE inhibitor treatment. The coronary vascular resistance (CVR) after ACE inhibitor treatment of the patients with CFR <2.0 decreased significantly compared with those with CFR ≥2.0 (p<0.03). These results indicate that hypertensive patients at the early stage show decreased coronary flow reserve despite having normal resting flow. Treatment with an ACE inhibitor (Cilazapril) for 12 weeks improved coronary flow reserve in 42% of our patients. The CVR of the patients with CFR <2.0 showed improvement compared to those with CFR ≥2.0. This result indicates that an ACE inhibitor (e.g., Cilazapril) should be one of the choices for improving CFR if hypertensive patients in early stage show signs of ischemia or diastolic dysfunction, which may be one of the sequels of reserve restriction. (author)

  17. Safety and efficacy of Y-90 microsphere treatment in patients with primary and metastatic liver cancer: The tumor selectivity of the treatment as a function of tumor to liver flow ratio

    Directory of Open Access Journals (Sweden)

    Dezarn William A


    Full Text Available Abstract Background Treatment records and follow-up data on 40 patients with primary and metastatic liver malignancies who underwent a single whole-liver treatment with Y-90 resin microspheres (SIR-Spheres® Sirtex Medical, Lake Forest, IL were retrospectively reviewed. The objective of the study was to evaluate the anatomic and physiologic determinants of radiation dose distribution, and the dose response of tumor and liver toxicity in patients with liver malignancies who underwent hepatic arterial Y-90 resin microsphere treatment. Methods Liver and tumor volume calculations were performed on pre-treatment CT scans. Fractional tumor and liver flow characteristics and lung shunt fractions were determined using hepatic arterial Tc-99m MAA imaging. Absorbed dose calculations were performed using the MIRD equations. Liver toxicity was assessed clinically and by liver function tests. Tumor response to therapy was assessed by CT and/or tumor markers. Results Of the 40 patients, 5 had hepatocellular cancer (HCC, and 35 had metastatic liver tumors (15 colorectal cancer, 10 neuroendocrine tumors, 4 breast cancer, 2 lung cancer, 1 ovarian cancer, 1 endometrial cancer, and 2 unknown primary adenocarcinoma. All patients were treated in a salvage setting with a 3 to 80 week follow-up (mean: 19 weeks. Tumor volumes ranged from 15.0 to 984.2 cc (mean: 294.9 cc and tumor to normal liver uptake ratios ranged from 2.8 to 15.4 (mean: 5.4. Average administered activity was 1.2 GBq (0.4 to 2.4 GBq. Liver absorbed doses ranged from 0.7 to 99.5 Gy (mean: 17.2 Gy. Tumor absorbed doses ranged from 40.1 to 494.8 Gy (mean: 121.5 Gy. None of the patients had clinical venoocclusive disease or therapy-induced liver failure. Seven patients (17.5 % had transient and 7 patients (17.5 % had persistent LFT abnormalities. There were 27 (67.5% responders (complete response, partial response, and stable disease. Tumor response correlated with higher tumor flow ratio as measured by

  18. UASB followed by Sub-Surface Horizontal Flow Phytodepuration for the Treatment of the Sewage Generated by a Small Rural Community

    Directory of Open Access Journals (Sweden)

    Massimo Raboni


    Full Text Available The paper presents the results of an experimental process designed for the treatment of the sewage generated by a rural community located in the north-east of Brazil. The process consists of a preliminary mechanical treatment adopting coarse screens and grit traps, followed by a biological treatment in a UASB reactor and a sub-surface horizontal flow phytodepuration step. The use of a UASB reactor equipped with a top cover, as well as of the phytodepuration process employing a porous medium, showed to present important health advantages. In particular, there were no significant odor emissions and there was no evidence of the proliferation of insects and other disease vectors. The plant achieved the following mean abatement efficiencies: 92.9% for BOD5, 79.2% for COD and 94% for Suspended Solids. With regard to fecal indicators average efficiencies of 98.8% for fecal coliforms and 97.9% for fecal enterococci were achieved. The UASB reactor showed an important role in achieving this result. The research was also aimed at evaluating the optimal operating conditions for the UASB reactor in terms of hydraulic load and organic volumetric loading. The achieved results hence indicated that the process may be highly effective for small rural communities in tropical and sub-tropical areas.

  19. Artificial intelligence based model for optimization of COD removal efficiency of an up-flow anaerobic sludge blanket reactor in the saline wastewater treatment. (United States)

    Picos-Benítez, Alain R; López-Hincapié, Juan D; Chávez-Ramírez, Abraham U; Rodríguez-García, Adrián


    The complex non-linear behavior presented in the biological treatment of wastewater requires an accurate model to predict the system performance. This study evaluates the effectiveness of an artificial intelligence (AI) model, based on the combination of artificial neural networks (ANNs) and genetic algorithms (GAs), to find the optimum performance of an up-flow anaerobic sludge blanket reactor (UASB) for saline wastewater treatment. Chemical oxygen demand (COD) removal was predicted using conductivity, organic loading rate (OLR) and temperature as input variables. The ANN model was built from experimental data and performance was assessed through the maximum mean absolute percentage error (= 9.226%) computed from the measured and model predicted values of the COD. Accordingly, the ANN model was used as a fitness function in a GA to find the best operational condition. In the worst case scenario (low energy requirements, high OLR usage and high salinity) this model guaranteed COD removal efficiency values above 70%. This result is consistent and was validated experimentally, confirming that this ANN-GA model can be used as a tool to achieve the best performance of a UASB reactor with the minimum requirement of energy for saline wastewater treatment.

  20. Application of Horizontal Subsurface Flow Constructed Wetland Systems for Domestic Wastewater Treatment: A Case Study, Kızılcaören

    Directory of Open Access Journals (Sweden)

    Fulya Aydın Temel


    Full Text Available Constructed wetlands (CWs are a green technology that have been used to treat several types of wastewater such as domestic, industrial, agricultural wastewaters and landfill leachate. CWs have several advantages included land intensive, low energy, easy operation and maintenance, low investment/operational costs, landscape esthetics, reuse of waters, and increased wildlife habitat compared to conventional systems. CWs are alternative treatment technologies due to these properties especially for rural settlements, industries, and hotels that are remote locations from central treatment plants. Physical, chemical, and biological treatment mechanisms can employ together in CWs. In the present study, two parallel full scale horizontal subsurface flow constructed wetlands were designed to treat domestic wastewater of Kızılcaören village in Samsun, Turkey. Juncus acutus and Cortaderia selloana were selected and the removal performance of each species were evaluated. During 7 months operation, the mean removal efficiencies of Juncus acutus and Cortaderia selloana were found as 33% and 32% for Mg2+; 62% and 55% for Fe2+; 64% and 56% for Fe3+; 46% and 37% for Cl2; 48% and 39% for total Cl2; 26% and 37% for Ca2+; 28% and 23% for SAA, respectively. Also, the Two-way ANOVA between groups was applied to determine any difference for the removal of all parameters between the plant types and months on the mean values of pollutants removal.

  1. Pharmaceutical and personal care products in domestic wastewater and their removal in anaerobic treatment systems: Septic tank – up flow anaerobic filter.

    Directory of Open Access Journals (Sweden)

    Juan Pablo Arrubla Vélez


    Full Text Available In several countries around the world, Pharmaceutical and Personal Care Products (PPCPs exist in aquatic environments, a fact that increases the awareness within the scientific community with respect to their possible fate and environment effects. This research presents a preliminary monitoring of use, consumption and presence of PPCPs in wastewater from a treatment plant in a rural area of Pereira (Colombia. Domestic sewage is treated in a septic tank followed by an Up-Flow Anaerobic Filter and its effluent is discharged into the Otún River, upstream of the water intake of the supply system of the city. The compounds monitored in this research included ibuprofen, naproxen, diclofenac, aspirin, ketoprofen, caffeine, galaxolide, tonalide and dihydrojasmonate. An adapted method of multi-residue analysis was used, which is based on solid phase extraction with hydrophilic-lipophilic balance cartridges, and determination by gas chromatography-mass spectrometry. The removal efficiencies demonstrated that the treatment plant could eliminate less than 50% of dihydrojasmonate, diclofenac and galaxolide existing in wastewater; concentration of aspirin, naproxen and tonalide could only be reduced in 15%; and caffeine, ibuprofen and ketoprofen were not removed. Results provided basic information to decide over the necessity of complementary treatments for effluents from systems with the mentioned units.

  2. Effects of a saturated layer and recirculation on nitrogen treatment performances of a single stage Vertical Flow Constructed Wetland (VFCW). (United States)

    Prigent, S; Paing, J; Andres, Y; Chazarenc, F


    Upgrades to enhance nitrogen removal were tested in a 2 year old pilot vertical flow constructed wetland in spring and summer periods. The effects of a saturated layer and of recirculation were tested in particular. Two pilots (L = 2 m, W = 1.25 m, H = 1.2 m), filled with expanded schist (Mayennite(®)), were designed with hydraulic saturated layers of 20 and 40 cm at the bottom. Each pilot was fed with raw domestic wastewater under field conditions according to a hydraulic load of 15-38 cm d(-1) (i.e. 158-401 g COD (chemical oxygen demand) m(-2) d(-1)) and to recirculation rates ranging from 0% up to 150%. The initial load during the first 2 years of operation resulted in an incomplete mineralized accumulated sludge leading to total suspended solids (TSS), COD and biochemical oxygen demand (BOD5) release. A 40 cm hydraulic saturated layer enabled an increase of 5-10% total nitrogen (TN) removal compared to a 20 cm saturated layer. Recirculation allowed the dilution of raw wastewater and enhanced nitrification in a single stage. A design of 1.8 m² pe(-1) (48 cm d(-1), 191 g COD m(-2) d(-1)) with a 40 cm saturated layer and 100% recirculation enabled the French standard D4 (35 mg TSS L(-1), 125 mg COD L(-1), 25 mg BOD5 L(-1)), nitrogen concentrations below 20 mg TKN (total Kjeldahl nitrogen) L(-1) and 50 mg TN L(-1), to be met.

  3. Tangential Flow Ultrafiltration Allows Purification and Concentration of Lauric Acid-/Albumin-Coated Particles for Improved Magnetic Treatment. (United States)

    Zaloga, Jan; Stapf, Marcus; Nowak, Johannes; Pöttler, Marina; Friedrich, Ralf P; Tietze, Rainer; Lyer, Stefan; Lee, Geoffrey; Odenbach, Stefan; Hilger, Ingrid; Alexiou, Christoph


    Superparamagnetic iron oxide nanoparticles (SPIONs) are frequently used for drug targeting, hyperthermia and other biomedical purposes. Recently, we have reported the synthesis of lauric acid-/albumin-coated iron oxide nanoparticles SEON(LA-BSA), which were synthesized using excess albumin. For optimization of magnetic treatment applications, SPION suspensions need to be purified of excess surfactant and concentrated. Conventional methods for the purification and concentration of such ferrofluids often involve high shear stress and low purification rates for macromolecules, like albumin. In this work, removal of albumin by low shear stress tangential ultrafiltration and its influence on SEON(LA-BSA) particles was studied. Hydrodynamic size, surface properties and, consequently, colloidal stability of the nanoparticles remained unchanged by filtration or concentration up to four-fold (v/v). Thereby, the saturation magnetization of the suspension can be increased from 446.5 A/m up to 1667.9 A/m. In vitro analysis revealed that cellular uptake of SEON(LA-BSA) changed only marginally. The specific absorption rate (SAR) was not greatly affected by concentration. In contrast, the maximum temperature Tmax in magnetic hyperthermia is greatly enhanced from 44.4 °C up to 64.9 °C by the concentration of the particles up to 16.9 mg/mL total iron. Taken together, tangential ultrafiltration is feasible for purifying and concentrating complex hybrid coated SPION suspensions without negatively influencing specific particle characteristics. This enhances their potential for magnetic treatment.

  4. Collaborative Research: A Model of Partially Ionized Plasma Flows with Kinetic Treatment of Neutral Atoms and Nonthermal Ions

    International Nuclear Information System (INIS)

    Pogorelov, Nikolai; Zhang, Ming


    Interactions of flows of partially ionized, magnetized plasma are frequently accompanied by the presence of both thermal and non-thermal (pickup) ion components. Such interactions cannot be modeled using traditional MHD equations and require more advanced approaches to treat them. If a nonthermal component of ions is formed due to charge exchange and collisions between the thermal (core) ions and neutrals, it experiences the action of magnetic field, its distribution function is isotropized, and it soon acquires the velocity of the ambient plasma without being thermodynamically equilibrated. This situation, e. g., takes place in the outer heliosphere -- the part of interstellar space beyond the solar system whose properties are determined by the solar wind interaction with the local interstellar medium. This is also possible in laboratory, at million degrees and above, when plasma is conducting electricity far too well, which makes Ohmic heating ineffective. To attain the target temperatures one needs additional heating eventually playing a dominant role. Among such sources is a so-called neutral particle beam heating. This is a wide-spread technique (Joint European Torus and International Thermonuclear Experimental Reactor experiments) based on the injection of powerful beams of neutral atoms into ohmically preheated plasma. In this project we have investigated the energy and density separation between the thermal and nonthermal components in the solar wind and interstellar plasmas. A new model has been developed in which we solve the ideal MHD equations for mixture of all ions and the kinetic Boltzmann equation to describe the transport of neutral atoms. As a separate capability, we can treat the flow of neutral atoms in a multi-component fashion, where neutral atoms born in each thermodynamically distinct region are governed by the Euler gas dynamic equations. We also describe the behavior of pickup ions either kinetically, using the Fokker--Planck equation, or

  5. Collaborative Research: A Model of Partially Ionized Plasma Flows with Kinetic Treatment of Neutral Atoms and Nonthermal Ions

    Energy Technology Data Exchange (ETDEWEB)

    Pogorelov, Nikolai [Univ. of Alabama, Huntsville, AL (United States). Dept. of Space Science. Center for Space Plasma and; Zhang, Ming [Florida Inst. of Technology, Melbourne, FL (United States). Physics and Space Sciences Dept.; Borovikov, Sergey [Univ. of Alabama, Huntsville, AL (United States). Dept. of Space Science. Center for Space Plasma and Aeronomic Research; Heerikhuisen, Jacob [Univ. of Alabama, Huntsville, AL (United States). Dept. of Space Science. Center for Space Plasma and Aeronomic Research; Zank, Gary [Univ. of Alabama, Huntsville, AL (United States). Dept. of Space Science. Center for Space Plasma and Aeronomic Research; Gamayunov, Konstantin [Florida Inst. of Technology, Melbourne, FL (United States). Physics and Space Sciences Dept.; Colella, Phillip [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)


    Interactions of flows of partially ionized, magnetized plasma are frequently accompanied by the presence of both thermal and non-thermal (pickup) ion components. Such interactions cannot be modeled using traditional MHD equations and require more advanced approaches to treat them. If a nonthermal component of ions is formed due to charge exchange and collisions between the thermal (core) ions and neutrals, it experiences the action of magnetic field, its distribution function is isotropized, and it soon acquires the velocity of the ambient plasma without being thermodynamically equilibrated. This situation, e. g., takes place in the outer heliosphere - the part of interstellar space beyond the solar system whose properties are determined by the solar wind interaction with the local interstellar medium. This is also possible in laboratory, at million degrees and above, when plasma is conducting electricity far too well, which makes Ohmic heating ineffective. To attain the target temperatures one needs additional heating eventually playing a dominant role. Among such sources is a so-called neutral particle beam heating. This is a wide-spread technique (Joint European Torus and International Thermonuclear Experimental Reactor experiments) based on the injection of powerful beams of neutral atoms into ohmically preheated plasma. In this project we have investigated the energy and density separation between the thermal and nonthermal components in the solar wind and interstellar plasmas. A new model has been developed in which we solve the ideal MHD equations for mixture of all ions and the kinetic Boltzmann equation to describe the transport of neutral atoms. As a separate capability, we can treat the flow of neutral atoms in a multi-component fashion, where neutral atoms born in each thermodynamically distinct regions are governed by the Euler gas dynamic equations. We also describe the behavior of pickup ions either kinetically, using the Fokker–Planck equation, or

  6. Collaborative Research: A Model of Partially Ionized Plasma Flows with Kinetic Treatment of Neutral Atoms and Nonthermal Ions

    Energy Technology Data Exchange (ETDEWEB)

    Pogorelov, Nikolai [Univ. of Alabama, Huntsville, AL (United States); Zhang, Ming [Florida Inst. of Technology, Melbourne, FL (United States)


    Interactions of flows of partially ionized, magnetized plasma are frequently accompanied by the presence of both thermal and non-thermal (pickup) ion components. Such interactions cannot be modeled using traditional MHD equations and require more advanced approaches to treat them. If a nonthermal component of ions is formed due to charge exchange and collisions between the thermal (core) ions and neutrals, it experiences the action of magnetic field, its distribution function is isotropized, and it soon acquires the velocity of the ambient plasma without being thermodynamically equilibrated. This situation, e. g., takes place in the outer heliosphere –- the part of interstellar space beyond the solar system whose properties are determined by the solar wind interaction with the local interstellar medium. This is also possible in laboratory, at million degrees and above, when plasma is conducting electricity far too well, which makes Ohmic heating ineffective. To attain the target temperatures one needs additional heating eventually playing a dominant role. Among such sources is a so-called neutral particle beam heating. This is a wide-spread technique (Joint European Torus and International Thermonuclear Experimental Reactor experiments) based on the injection of powerful beams of neutral atoms into ohmically preheated plasma. In this project we have investigated the energy and density separation between the thermal and nonthermal components in the solar wind and interstellar plasmas. A new model has been developed in which we solve the ideal MHD equations for mixture of all ions and the kinetic Boltzmann equation to describe the transport of neutral atoms. As a separate capability, we can treat the flow of neutral atoms in a multi-component fashion, where neutral atoms born in each thermodynamically distinct region are governed by the Euler gas dynamic equations. We also describe the behavior of pickup ions either kinetically, using the Fokker--Planck equation

  7. Improved petroleum refinery wastewater treatment and seawater desalination performance by combining osmotic microbial fuel cell and up-flow microbial desalination cell. (United States)

    Sevda, Surajbhan; Abu-Reesh, Ibrahim M


    The petroleum refinery wastewater which is a product of petroleum refinery has a high organic content. This study explores the utilization of petroleum refinery wastewater collected from petroleum refinery as a resource for bioelectricity generation and using this energy for salt removal from seawater in a hydraulically connected osmotic microbial fuel cell (OsMFC) and up flow microbial desalination cell (UMDC). Anaerobic mixed sludge was used in the anodic chamber of OsMFC and UMDC. Petroleum refinery wastewater was fed first into the OsMFC and then transferred to the UMDC. The OsMFC and UMDC were connected to 1000 and 100 Ω external resistance respectively. Experimental results showed that the combined system could remove 93% of chemical oxygen demand (COD) from the petroleum refinery wastewater whilst 48% salts were removed from the seawater. Experimental results showed that this complex wastewater can be treated and produce bioelectricity, with COD removal and salt removal. The hydraulically connected OsMFC and up flow MDC provide a suitable platform for wastewater treatment and seawater desalination.

  8. The Effect of the Treatment with Heated Humidified High-Flow Nasal Cannula on Neonatal Respiratory Distress Syndrome in China: A Single-Center Experience

    Directory of Open Access Journals (Sweden)

    Ge Zheng


    Full Text Available Background. Noninvasive respiratory support is considered the optimal method of providing assistance to preterm babies with breathing problems, including nasal continuous positive airway pressure (NCPAP and humidified high flow nasal cannula (HHHFNC. The evidence of the efficacy and safety of HHHFNC used as the primary respiratory support for respiratory distress syndrome (RDS is insufficient in low- and middle-income countries. Objective. To investigate the effect of heated humidified high flow nasal cannula on neonatal respiratory distress syndrome compared with nasal continuous positive airway pressure. Methods. An observational cross-sectional study was performed at a tertiary neonatal intensive care unit in suburban Wenzhou, China, in the period between January 2014 and December 2015. Results. A total of 128 infants were enrolled in the study: 65 in the HHHFNC group and 63 in the NCPAP group. The respiratory support with HHHFNC was similar to that with NCPAP with regard to the primary outcome. There is no significant difference between two groups in secondary outcomes. Comparing with NCPAP group, the incidence of nasal damage was lower in HHHFNC group. Conclusions. HHHFNC is an effective and well-tolerated strategy as the primary treatment of mild to moderate RDS in preterm infants older than 28 weeks of GA.

  9. Unravelling the spatial variation of nitrous oxide emissions from a step-feed plug-flow full scale wastewater treatment plant. (United States)

    Pan, Yuting; van den Akker, Ben; Ye, Liu; Ni, Bing-Jie; Watts, Shane; Reid, Katherine; Yuan, Zhiguo


    Plug-flow activated sludge reactors (ASR) that are step-feed with wastewater are widely adopted in wastewater treatment plants (WWTPs) due to their ability to maximise the use of the organic carbon in wastewater for denitrification. Nitrous oxide (N2O) emissions are expected to vary along these reactors due to pronounced spatial variations in both biomass and substrate concentrations. However, to date, no detailed studies have characterised the impact of the step-feed configuration on emission variability. Here we report on the results from a comprehensive online N2O monitoring campaign, which used multiple gas collection hoods to simultaneously measure emission along the length of a full-scale, step-fed, plug-flow ASR in Australia. The measured N2O fluxes exhibited strong spatial-temporal variation along the reactor path. The step-feed configuration had a substantial influence on the N2O emissions, where the N2O emission factors in sections following the first and second step feed were 0.68% ± 0.09% and 3.5% ± 0.49% of the nitrogen load applied to each section. The relatively high biomass-specific nitrogen loading rate in the second section of the reactor was most likely cause of the high emissions from this section.

  10. Treatment

    Directory of Open Access Journals (Sweden)

    Safaa M. Raghab


    The main goal of this study is to utilize a natural low cost material “as an accelerator additive to enhance the chemical treatment process using Alum coagulant and the accelerator substances were Perlite and Bentonite. The performance of the chemical treatment was enhanced using the accelerator substances with 90 mg/l Alum as a constant dose. Perlite gave better performance than the Bentonite effluent. The removal ratio for conductivity, turbidity, BOD and COD for Perlite was 86.7%, 87.4%, 89.9% and 92.8% respectively, and for Bentonite was 83.5%, 85.0%, 86.5% and 85.0% respectively at the same concentration of 40 mg/l for each.

  11. Evaluation of a treatment system type septic tank - filter anaerobic of upward flow for the residual waters of the ecological benefit of the coffee

    International Nuclear Information System (INIS)

    Sanchez C, Jose Alejandro


    Colombia is the first country in the production of soft coffee in the world. The benefit for humid way it makes that this quality of coffee is obtained; however, the high consumption of water in the process and the later discharge to the superficial or underground sources, they have generated an environmental problem of great magnitude. Also, the sources of water that they have been contaminated with the discharges of the liquid waste that come from benefit of coffee they present, among other, serious inconveniences to be used as supplying sources of drinkable water. In time of crop, the coffee areas and their superficial sources of water usually register high indexes of contamination like consequence of the discharges of residual waters that come from the benefit of the coffee. In the Departments of Quindio, Valle, Caldas, Antioquia, etc., they have been come executing investigations of the residuals treatment that are derived of the pulp removal of the coffee (via humid), for anaerobic methods with satisfactory results. This project had the collaboration of the Departmental Committee of Coffee of Antioquia and the Environmental Engineering of the Antioquia University and it is formulated toward the evaluation of a Anaerobic filter of Ascendant flow, FAFA, preceded of a septic tank (biological sedimentation), as a treatment system of the coffee residual waters, with a waste native of a ecological benefit area. The obtained results were satisfactory although the generated waste is very intermittent and in times that are not of coffee crop it doesn't take place; what hinders more the application of biological systems for its treatment

  12. Long-term effects of oxygen-enriched high-flow nasal cannula treatment in COPD patients with chronic hypoxemic respiratory failure

    Directory of Open Access Journals (Sweden)

    Storgaard LH


    Full Text Available Line Hust Storgaard,1 Hans-Ulrich Hockey,2 Birgitte Schantz Laursen,3,4 Ulla Møller Weinreich1,3 1Department of Respiratory Diseases, Aalborg University Hospital, Aalborg, Denmark; 2Biometrics Matters Limited, Hamilton, New Zealand; 3Department of Clinical Medicine, Aalborg University, Aalborg, Denmark; 4Clinical Nursing Research Unit, Aalborg University Hospital, Aalborg, Denmark Background: This study investigated the long-term effects of humidified high-flow nasal cannula (HFNC in COPD patients with chronic hypoxemic respiratory failure treated with long-term oxygen therapy (LTOT.Patients and methods: A total of 200 patients were randomized into usual care ± HFNC. At inclusion, acute exacerbation of COPD (AECOPD and hospital admissions 1 year before inclusion, modified Medical Research Council (mMRC score, St George’s Respiratory Questionnaire (SGRQ, forced expiratory volume in 1 second (FEV1, 6-minute walk test (6MWT and arterial carbon dioxide (PaCO2 were recorded. Patients completed phone interviews at 1, 3 and 9 months assessing mMRC score and AECOPD since the last contact. At on-site visits (6 and 12 months, mMRC, number of AECOPD since last contact and SGRQ were registered and FEV1, FEV1%, PaCO2 and, at 12 months, 6MWT were reassessed. Hospital admissions during the study period were obtained from hospital records. Hours of the use of HFNC were retrieved from the high-flow device.Results: The average daily use of HFNC was 6 hours/day. The HFNC group had a lower AECOPD rate (3.12 versus 4.95/patient/year, p<0.001. Modeled hospital admission rates were 0.79 versus 1.39/patient/year for 12- versus 1-month use of HFNC, respectively (p<0.001. The HFNC group had improved mMRC scores from 3 months onward (p<0.001 and improved SGRQ at 6 and 12 months (p=0.002, p=0.033 and PaCO2 (p=0.005 and 6MWT (p=0.005 at 12 months. There was no difference in all-cause mortality.Conclusion: HFNC treatment reduced AECOPD, hospital admissions and

  13. The correlation between the rise of the tumor temperature during the hyperthermia treatment and the tumor blood flow measured by dynamic CT and 15O gas-positron emission tomography

    International Nuclear Information System (INIS)

    Hattori, Hideyuki


    This study was designed to determine the correlation between the rise of tumor temperature during hyperthermia treatment and the blood flow of the tumors measured by dynamic CT (DCT) and 15 O gas-positron emission tomography. In this report, we observed 20 patients with malignant tumors which underwent hyperthermia treatment. In each case, the temperature of the tumor was monitored with a photofiber sensor. DCT's and 15 O gas-positron emission tomographies were applied before the hyperthermia treatment. During the DCT, the tumor blood flow of each tumor was estimated by analyzing the time-dependent activity curve after a bolus injection. During the 15 O gas-positron emission tomography, the tumor blood flow was estimated by the C 15 O 2 -steady-state method. The value of the tumor blood flow estimated by DCT were proportional to those calculated by the 15 O gas-positron emission tomography. These values were inversely proportional to the rise of the temperature of the tumors during hyperthermia treatment. Our results imply that DCT as well as the 15 O gas-positron emission tomography can be used for the prediction of the tumor temperature rise during the hyperthermia treatment. (author)

  14. Start-up adjustment of a plug-flow digester for cassava wastewater (manipueira treatment Processo de partida de um biodigestor do tipo plug-flow para tratamento da manipueira

    Directory of Open Access Journals (Sweden)

    Maria Magdalena Ferreira Ribas


    Full Text Available Manipueira, wastewater of cassava (Manihot esculenta processing, can be treated by anaerobic biodigestion. To study the start-up process of a plug-flow digester for manipueira treatment, this work consisted of two stages: gradual decrease of the hydraulic retention time (HRT to the preset time of 4 days or maintaining a fixed HRT of 4 days with gradual increase of the substrate concentration. A digester of 1980 mL capacity was opperated, at constant temperature (32 ± 1º C, with substrate pH corrected between 5.5 and 6.0. The first stage had durations of 16.6; 13.6; 11.6; and 9.6 days and the organic loads were 3.1; 2.0; 2.3; and 2.9 COD L-1 d-1, (chemical oxigen demand respectively. The second stage was characterized by a fixed HRT (4 days and organic loads of 0.48; 0.86; 1.65; and 2.46 g COD L-1 d-1. Total solids (TS, volatile solids (VS, COD, alkalinity and volatile acidity were determined in the substrate and in the effluent. During the first stage, the HRT of 9.6 days and organic load of 2.9 g COD L-1 d-1 resulted in the best performence; reductions in COD, total and volatile solids were 60, 44 and 60%, respectively. During the second stage, with a 4-day HRT, the best results were achieved with the 0.86 g COD L-1 d-1 organic load, which provided reductions in COD, total and volatile solids of 71, 58 and 79%, respectively. The start-up of the plug-flow digester for manipueira treatment can be made by gradually by decreasing the HRT, or fixing HRT and increasing substrate concentration.Um dos resíduos gerados no processamento da mandioca (Manihot esculenta é a manipueira, passível de tratamento por biodigestão anaeróbia. Este trabalho objetivou estudar o processo de partida de um biodigestor tipo plug-flow, tratando manipueira de duas maneiras: diminuindo-se gradativamente o tempo de retenção hidráulica (TRH até se chegar ao tempo pré-estabelecido, quatro dias; ou mantendo-se o TRH fixo em quatro dias e aumentando-se gradativamente

  15. Continuous-flow photocatalytic treatment of pharmaceutical micropollutants: Activity, inhibition, and deactivation of TiO2 photocatalysts in wastewater effluent

    KAUST Repository

    Carbonaro, Sean


    Titanium dioxide (TiO2) photocatalysts have been shown to be effective at degrading a wide range of organic micropollutants during short-term batch experiments conducted under ideal laboratory solution conditions (e.g., deionized water). However, little research has been performed regarding longer-term photocatalyst performance in more complex matrices representative of contaminated water sources (e.g., wastewater effluent, groundwater). Here, a benchtop continuous-flow reactor was developed for the purpose of studying the activity, inhibition, and deactivation of immobilized TiO2 photocatalysts during water treatment applications. As a demonstration, degradation of four pharmaceutical micropollutants (iopromide, acetaminophen, sulfamethoxazole, and carbamazepine) was monitored in both a pH-buffered electrolyte solution and a biologically treated wastewater effluent (WWE) to study the effects of non-target constituents enriched in the latter matrix. Reactor performance was shown to be stable over 7d when treating micropollutants in buffered electrolyte, with 7-d averaged kobs values (acetaminophen=0.97±0.10h-1; carbamazepine=0.50±0.04h-1; iopromide=0.49±0.03h-1; sulfamethoxazole=0.79±0.06h-1) agreeing closely with measurements from short-term circulating batch reactions. When reactor influent was switched to WWE, treatment efficiencies decreased to varying degrees (acetaminophen=40% decrease; carbamazepine=60%; iopromide=78%; sulfamethoxazole=54%). A large fraction of the catalyst activity was recovered upon switching back to the buffered electrolyte influent after 4d, suggesting that much of the observed decrease resulted from reversible inhibition by non-target constituents (e.g., scavenging of photocatalyst-generated OH). However, there was also a portion of the decrease in activity that was not recovered, indicating WWE constituents also contributed to photocatalyst deactivation (acetaminophen=6% deactivation; carbamazepine=24%; iopromide=16

  16. [Impact of screening and treatment of low systemic blood flow in the prevention of severe intraventricular haemorrhage and/or death in pre-term infants]. (United States)

    Oulego Erroz, Ignacio; Alonso Quintela, Paula; Jiménez Gonzalez, Aquilina; Terroba Seara, Sandra; Rodríguez Blanco, Silvia; Rosón Varas, María; Castañón López, Leticia


    To assess the effect of a protocolised intervention for low systemic blood flow (SBF) in the occurrence of severe intraventricular haemorrhage (IVH) or death in pre-term infants. A study with a quasi-experimental design with retrospective controls was conducted on pre-term infants of less than 30weeks of gestational age, born between January 2016 and July 2017, who were consecutively included in the intervention period. The control cohort included pre-term infants (born between January 2013 and December 2015) matched by gestational age, birth weight, and gender (two controls for each case). The cases of low SBF diagnosed according to functional echocardiography during the study period received dobutamine (5-10μg/kg/min) for 48hours. The study included 29 cases (intervention period) and 54 controls (pre-intervention period). Ten out of 29 (34.5%) infants received dobutamine for low SBF during the intervention period, with 3/29 (10.3%) cases of severe IVH and/or death compared to 17/54 (31.5%) in the control cohort (p=.032). There was an independent association between the intervention and a decreased occurrence of severe IVH/death after adjusting for confounding factors both in the logistic regression model [OR 0.11 (95%CI: 0.01-0.65), p=.015], as well as in the sensitivity analysis using inverse probability of treatment weighting [OR 0.23 (95%CI: 0.09-0.56); p=.001]. In this study with retrospective controls, a protocolised screening, and treatment for low SBF was associated with a decreased occurrence of severe IVH or death in preterm infants. Large, adequately powered trials, are needed in order to determine whether postnatal interventions directed at low SBF can improve neurological outcomes. Copyright © 2018. Publicado por Elsevier España, S.L.U.

  17. Domestic wastewater treatment and power generation in continuous flow air-cathode stacked microbial fuel cell: Effect of series and parallel configuration. (United States)

    Estrada-Arriaga, Edson Baltazar; Hernández-Romano, Jesús; García-Sánchez, Liliana; Guillén Garcés, Rosa Angélica; Bahena-Bahena, Erick Obed; Guadarrama-Pérez, Oscar; Moeller Chavez, Gabriela Eleonora


    In this study, a continuous flow stack consisting of 40 individual air-cathode MFC units was used to determine the performance of stacked MFC during domestic wastewater treatment operated with unconnected individual MFC and in series and parallel configuration. The voltages obtained from individual MFC units were of 0.08-1.1 V at open circuit voltage, while in series connection, the maximum power and current density were 2500 mW/m 2 and 500 mA/m 2 (4.9 V), respectively. In parallel connection, the maximum power and current density was 5.8 mW/m 2 and 24 mA/m 2 , respectively. When the cells were not connected to each other MFC unit, the main bacterial species found in the anode biofilms were Bacillus and Lysinibacillus. After switching from unconnected to series and parallel connections, the most abundant species in the stacked MFC were Pseudomonas aeruginosa, followed by different Bacilli classes. This study demonstrated that when the stacked MFC was switched from unconnected to series and parallel connections, the pollutants removal, performance electricity and microbial community changed significantly. Voltages drops were observed in the stacked MFC, which was mainly limited by the cathodes. These voltages loss indicated high resistances within the stacked MFC, generating a parasitic cross current. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Evaluation of an up-flow anaerobic sludge bed (UASB) reactor containing diatomite and maifanite for the improved treatment of petroleum wastewater. (United States)

    Chen, Chunmao; Liang, Jiahao; Yoza, Brandon A; Li, Qing X; Zhan, Yali; Wang, Qinghong


    Novel diatomite (R1) and maifanite (R2) were utilized as support materials in an up-flow anaerobic sludge bed (UASB) reactor for the treatment of recalcitrant petroleum wastewater. At high organic loadings (11kg-COD/m 3 ·d), these materials were efficient at reducing COD (92.7% and 93.0%) in comparison with controls (R0) (88.4%). Higher percentages of large granular sludge (0.6mm or larger) were observed for R1 (30.3%) and R2 (24.6%) compared with controls (22.6%). The larger portion of granular sludge provided a favorable habitat that resulted in greater microorganism diversity. Increased filamentous bacterial communities are believed to have promoted granular sludge formation promoting a conductive environment for stimulation methanogenic Archaea. These communities had enhanced pH tolerance and produced more methane. This study illustrates a new potential use of diatomite and maifanite as support materials in UASB reactors for increased efficiency when treating refractory wastewaters. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Modeling the performance of 'up-flow anaerobic sludge blanket' reactor based wastewater treatment plant using linear and nonlinear approaches-A case study

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Kunwar P., E-mail: [Environmental Chemistry Division, Indian Institute of Toxicology Research (Council of Scientific and Industrial Research), Post Box No. 80, MG Marg, Lucknow-226 002, UP (India); Basant, Nikita [School of Graduate Studies-Multiscale Modeling, Computational Simulations and Characterization in Material and Life Sciences, University of Modena and Reggio E., Modena (Italy); Malik, Amrita; Jain, Gunja [Environmental Chemistry Division, Indian Institute of Toxicology Research (Council of Scientific and Industrial Research), Post Box No. 80, MG Marg, Lucknow-226 002, UP (India)


    The paper describes linear and nonlinear modeling of the wastewater data for the performance evaluation of an up-flow anaerobic sludge blanket (UASB) reactor based wastewater treatment plant (WWTP). Partial least squares regression (PLSR), multivariate polynomial regression (MPR) and artificial neural networks (ANNs) modeling methods were applied to predict the levels of biochemical oxygen demand (BOD) and chemical oxygen demand (COD) in the UASB reactor effluents using four input variables measured weekly in the influent wastewater during the peak (morning and evening) and non-peak (noon) hours over a period of 48 weeks. The performance of the models was assessed through the root mean squared error (RMSE), relative error of prediction in percentage (REP), the bias, the standard error of prediction (SEP), the coefficient of determination (R{sup 2}), the Nash-Sutcliffe coefficient of efficiency (E{sub f}), and the accuracy factor (A{sub f}), computed from the measured and model predicted values of the dependent variables (BOD, COD) in the WWTP effluents. Goodness of the model fit to the data was also evaluated through the relationship between the residuals and the model predicted values of BOD and COD. Although, the model predicted values of BOD and COD by all the three modeling approaches (PLSR, MPR, ANN) were in good agreement with their respective measured values in the WWTP effluents, the nonlinear models (MPR, ANNs) performed relatively better than the linear ones. These models can be used as a tool for the performance evaluation of the WWTPs.

  20. Modeling the performance of 'up-flow anaerobic sludge blanket' reactor based wastewater treatment plant using linear and nonlinear approaches-A case study

    International Nuclear Information System (INIS)

    Singh, Kunwar P.; Basant, Nikita; Malik, Amrita; Jain, Gunja


    The paper describes linear and nonlinear modeling of the wastewater data for the performance evaluation of an up-flow anaerobic sludge blanket (UASB) reactor based wastewater treatment plant (WWTP). Partial least squares regression (PLSR), multivariate polynomial regression (MPR) and artificial neural networks (ANNs) modeling methods were applied to predict the levels of biochemical oxygen demand (BOD) and chemical oxygen demand (COD) in the UASB reactor effluents using four input variables measured weekly in the influent wastewater during the peak (morning and evening) and non-peak (noon) hours over a period of 48 weeks. The performance of the models was assessed through the root mean squared error (RMSE), relative error of prediction in percentage (REP), the bias, the standard error of prediction (SEP), the coefficient of determination (R 2 ), the Nash-Sutcliffe coefficient of efficiency (E f ), and the accuracy factor (A f ), computed from the measured and model predicted values of the dependent variables (BOD, COD) in the WWTP effluents. Goodness of the model fit to the data was also evaluated through the relationship between the residuals and the model predicted values of BOD and COD. Although, the model predicted values of BOD and COD by all the three modeling approaches (PLSR, MPR, ANN) were in good agreement with their respective measured values in the WWTP effluents, the nonlinear models (MPR, ANNs) performed relatively better than the linear ones. These models can be used as a tool for the performance evaluation of the WWTPs.

  1. Enhanced treatment of Fischer-Tropsch wastewater using up-flow anaerobic sludge blanket system coupled with micro-electrolysis cell: A pilot scale study. (United States)

    Wang, Dexin; Han, Yuxing; Han, Hongjun; Li, Kun; Xu, Chunyan


    The coupling of micro-electrolysis cell (MEC) with an up-flow anaerobic sludge blanket (UASB) system in pilot scale was established for enhanced treatment of Fischer-Tropsch (F-T) wastewater. The lowest influent pH (4.99±0.10) and reduced alkali addition were accomplished under the assistance of anaerobic effluent recycling of 200% (stage 5). Simultaneously, the optimum COD removal efficiency (93.5±1.6%) and methane production (2.01±0.13m 3 /m 3 ·d) at the lower hydraulic retention time (HRT) were achieved in this stage. In addition, the dissolved iron from MEC could significantly increase the protein content of tightly bound extracellular polymeric substances (TB-EPS), which was beneficial to formation of stable granules. Furthermore, the high-throughput 16S rRNA gene pyrosequencing in this study further confirmed that Geobacter species could utilize iron oxides particles as electron conduit to perform the direct interspecies electron transfer (DIET) with Methanothrix, finally facilitating the syntrophic degradation of propionic acid and butyric acid and contributing completely methane production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Development of a sixth-generation down-flow hanging sponge (DHS) reactor using rigid sponge media for post-treatment of UASB treating municipal sewage. (United States)

    Onodera, Takashi; Tandukar, Madan; Sugiyana, Doni; Uemura, Shigeki; Ohashi, Akiyoshi; Harada, Hideki


    A sixth-generation down-flow hanging sponge reactor (DHS-G6), using rigid sponge media, was developed as a novel aerobic post-treatment unit for upflow anaerobic sludge blanket (UASB) treating municipal sewage. The rigid sponge media were manufactured by copolymerizing polyurethane with epoxy resin. The UASB and DHS system had a hydraulic retention time (HRT) of 10.6 h (8.6 h for UASB and 2 h for DHS) when operated at 10-28 °C. The system gave reasonable organic and nitrogen removal efficiencies. The final effluent had a total biochemical oxygen demand of only 12 mg/L and a total Kjeldahl nitrogen content of 6 mg/L. The DHS reactor gave particularly good nitrification performance, which was attributed to the new rigid sponge media. The sponge media helped to provide a sufficient HRT, and retained a high biomass concentration, extending the solids retention time. The DHS reactor maintained a high dissolved oxygen concentration under natural ventilation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. The use of palm kernel shell (PKS) as substrate material in vertical-flow engineered wetlands for septage treatment in Malaysia. (United States)

    Jong, Valerie Siaw Wee; Tang, Fu Ee


    In this study, the treatment of septage (originating from septic tanks) was carried out in a pilot-scale, two-staged, vertical-flow engineered wetland (VFEW). Palm kernel shells (PKS) were incorporated as part of the VFEW's substrate (B-PKS), to compare its organic matter (OM) and nitrogen (N) removal efficiency against wetlands with only sand substrates (B-SD). The results revealed satisfactory OM removal with >90% reduction efficiencies at both wetlands B-PKS and B-SD. No increment of chemical oxygen demand (COD) concentration was observed in the effluent of B-PKS. Ammonia load removal efficiencies were comparable (>91% and 95% in wetland B-PKS and B-SD, respectively). However, nitrate accumulation was observed in the effluent of B-SD where PKS was absent. This was due to the limited denitrification in B-SD, as sand is free of carbon. A lower nitrate concentration was associated with higher COD concentration in the effluent at B-PKS. This study has shown that the use of PKS was effective in improving the N removal efficiency in engineered wetlands.

  4. Improvement of biological nitrogen removal with nitrate-dependent Fe(II) oxidation bacterium Aquabacterium parvum B6 in an up-flow bioreactor for wastewater treatment. (United States)

    Zhang, Xiaoxin; Li, Ang; Szewzyk, Ulrich; Ma, Fang


    Aquabacterium parvum strain B6 exhibited efficient nitrate-dependent Fe(II) oxidation ability using nitrate as an electron acceptor. A continuous up-flow bioreactor that included an aerobic and an anoxic section was constructed, and strain B6 was added to the bioreactor as inocula to explore the application of microbial nitrate-dependent Fe(II) oxidizing (NDFO) efficiency in wastewater treatment. The maximum NRE (anoxic section) and TNRE of 46.9% and 79.7%, respectively, could be obtained at a C/N ratio of 5.3:1 in the influent with HRT of 17. Meanwhile, the taxonomy composition of the reactor was assessed, as well. The NDFO metabolism of strain B6 could be expected because of its relatively dominant position in the anoxic section, whereas potential heterotrophic nitrification and aerobic denitrification developed into the prevailing status in the aerobic section after 50days of continuous operation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Performance comparison and economics analysis of waste stabilization ponds and horizontal subsurface flow constructed wetlands treating domestic wastewater: a case study of the Juja sewage treatment works. (United States)

    Mburu, Njenga; Tebitendwa, Sylvie M; van Bruggen, Johan J A; Rousseau, Diederik P L; Lens, Piet N L


    The performance, effluent quality, land area requirement, investment and operation costs of a full-scale waste stabilization pond (WSP) and a pilot scale horizontal subsurface flow constructed wetland (HSSF-CW) at Jomo Kenyatta University of Agriculture and Technology (JKUAT) were investigated between November 2010 to January 2011. Both systems gave comparable medium to high levels of organic matter and suspended solids removal. However, the WSP showed a better removal for Total Phosphorus (TP) and Ammonium (NH4(+)-N). Based on the population equivalent calculations, the land area requirement per person equivalent of the WSP system was 3 times the area that would be required for the HSSF-CW to treat the same amount of wastewater. The total annual cost estimates consisting of capital, operation and maintenance (O&M) costs were comparable for both systems. However, the evaluation of the capital cost of either system showed that it is largely influenced by the size of the population served, local cost of land and the construction materials involved. Hence, one can select either system in terms of treatment efficiency. When land is available other factor including the volume of wastewater or the investment, and O&M costs determine the technology selection. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Treatment of hydrocephalus determined by the European Orbis Sigma Valve II survey: a multicenter prospective 5-year shunt survival study in children and adults in whom a flow-regulating shunt was used

    NARCIS (Netherlands)

    Hanlo, Patrick W.; Cinalli, Giuseppe; Vandertop, W. Peter; Faber, Joop A. J.; Bøgeskov, Lars; Børgesen, Svend E.; Boschert, Jürgen; Chumas, Paul; Eder, Hans; Pople, Ian K.; Serlo, Willy; Vitzthum, Eckehard


    OBJECT: The goal of this study was to evaluate the long-term results of a flow-regulating shunt (Orbis Sigma Valve [OSV] II Smart Valve System; Integra NeuroSciences, Sophia Antipolis, France) in the treatment of hydrocephalus, whether it was a first insertion procedure or surgical revision of

  7. A study on the effects of different hydraulic loading rates (HLR) on pollutant removal efficiency of subsurface horizontal-flow constructed wetlands used for treatment of domestic wastewaters. (United States)

    Çakir, Recep; Gidirislioglu, Ali; Çebi, Ulviye


    The research into the treatment of domestic wastewaters originating from Büyükdöllük village in Edirne Province was carried out over a 3 year experimental period. The wastewaters of the settlement were treated using a constructed wetland with subsurface horizontal flow, and the effects of different hydraulic loading levels on removal efficiency were studied. In order to achieve this goal, three equal chambers (ponds) of 300 m(2) each were constructed and planted with Phragmites australis. Each of the chambers was loaded with domestic wastewater with average flow discharge creating hydraulic loading rates of 0. m(3) day(-1) m(-2); 0.075 m(3) day(-1) m(-2) and 0.125 m(3) day(-1) m(-2), respectively. According to the results of the study, the inlet levels of the pollutant parameters with carbon origin in the water samples taken from the system entrance are high and the average values for three years are respectively: Biological Oxygen Demand, BOD5 -324.5 mg L(-1); Chemical Oxygen Demand, COD -484,0 mg L(-1); suspended solids (TSS) -147.3 mg L(-1) and Oil and Grease -0.123 mg L(-1). It was also determined that the removal rates of the system were closely dependent on the applied hydraulic loading levels and the highest removal rates of 64.9%, 62.5%, 86.3% and 80.34% for BOD5, COD, TSS and Oil and Grease, respectively, were determined in the pond with a hydraulic loading rate of 0.050 m(3) day(-1) m(-2). Lower removal of 57.9%, 55.5%, 81.4% and 74.5% for BOD5, COD, TSS and Oil and Grease were recorded in the pond with a hydraulic loading rate of 0.075 m(3) day(-1) m(-2); and these values were 49.1%, 47.8%, 70.9% and 62.1% for the pond with a hydraulic loading rate of 0.125 m(3) day(-1) m(-2). High removal rates were also recorded for the other investigated pollution parameters. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Development and Deployment of a Full-Scale Cross-Flow Filtration System for Treatment of Liquid Low-Level Waste at Oak Ridge National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Kent, T.E.


    A full-scale modular solid/liquid separation (SLS) system was designed, fabricated, installed, and successfully deployed for treatment of liquid low-level waste from the Melton Valley Storage Tanks (MVSTs) at Oak Ridge National Laboratory (ORNL). The SLS module, utilizing cross-flow filtration, was operated as part of an integrated tank waste pretreatment system (otherwise known as the Wastewater Triad) to remove suspended solids and prevent fouling of ion-exchange materials and heat exchange surfaces. The information gained from this testing was used to complete design specifications for the full-scale modular SLS system in May 1997. The contract for detailed design and fabrication of the system was awarded to NUMET in July 1997, and the design was completed in January 1998. Fabrication began in March 1998, and the completed system was delivered to ORNL on December 29, 1998. Installation of the system at the MVST facility was completed in May 1999. After completing an operational readiness assessment, approval was given to commence hot operations on June 7, 1999. Operations involving two of the eight MVSTs were performed safely and with very little unscheduled downtime. Filtration of supernatant from tank W-31 was completed on June 24, 1999 and W-26 processing was completed on August 20, 1999. The total volume processed during these two campaigns was about 45,000 gal. The suspended solids content of the liquid processed from tank W-31 was lower than expected, resulting in higher-than-expected filtrate production for nearly the entire operation. The liquid processed from tank W-26 was higher in suspended solids content, and filtrate production was lower, but comparable to the rates expected based on the results of previous pilot-scale, single-element filtration tests. The quality of the filtrate consistently met the requirements for feed to the downstream ion-exchange and evaporation processes. From an equipment and controls standpoint, the modular system (pumps

  9. Endovascular treatment of intracranial aneurysms with the p64 flow diverter stent: mid-term results in 35 patients with 41 intracranial aneurysms. (United States)

    Morais, Ricardo; Mine, Benjamin; Bruyère, Pierre Julien; Naeije, Gilles; Lubicz, Boris


    The p64 flow diverter (FD) device is a fully resheathable and detachable stent dedicated for endovascular treatment (EVT) of intracranial aneurysms (IAs). We report our mid-term experience with this device. Between January 2015 and February 2016, we retrospectively identified, in our prospectively maintained database, all patients treated with p64 FDs in two institutions. Independent clinical follow-up was performed by a vascular neurologist. Imaging follow-up included a digitalized subtraction angiography (DSA) at 3, 6, and 12 months and a magnetic resonance angiography (MRA) at 12 months. Thirty-nine patients (22 women/17 men; median age 54 years) with 48 IAs (median aneurysm size 6.2 mm; mean neck size 3.4 mm) were identified. All IAs were saccular and unruptured. Failure of safe stent delivery occurred in 15% of cases (7/48 IAs) which were excluded. Transient neurological morbidity occurred in 2/35 patients (5.7%) including one delayed thromboembolic complication. No permanent morbidity or mortality was encountered. Complete aneurysmal occlusion at 3, 6, and 12 months was 20/30 (66.6%), 18/27 (66.6%), and 24/28 (85.7%), respectively. Intra-stent stenosis was observed in 9/29 patients (31%) and classified as moderate in 4/29 (13.7%) and mild in 5/29 patients (17.2%). These stenoses gradually improved over time, with only mild stenoses being identified at 6 months and at 12 months. In our small case series, the p64 FD stent appears safe and effective for EVT of IAs. A high occlusion rate and a low morbidity rate were observed.

  10. Flow visualization

    CERN Document Server

    Merzkirch, Wolfgang


    Flow Visualization describes the most widely used methods for visualizing flows. Flow visualization evaluates certain properties of a flow field directly accessible to visual perception. Organized into five chapters, this book first presents the methods that create a visible flow pattern that could be investigated by visual inspection, such as simple dye and density-sensitive visualization methods. It then deals with the application of electron beams and streaming birefringence. Optical methods for compressible flows, hydraulic analogy, and high-speed photography are discussed in other cha

  11. Influence of different flow conditions on the occurrence and behavior of potentially hazardous organic xenobiotics in the influent and effluent of a municipal sewage treatment plant in Germany: an effect-directed approach

    Energy Technology Data Exchange (ETDEWEB)

    Faber, Peter [University of Trier (Germany). Department of Hydrology; Max-Planck-Institute for Chemistry, Mainz (Germany). Particle Chemistry Dept.; Bierl, Reinhard [University of Trier (Germany). Department of Hydrology


    Flow conditions in the sewer systems are particularly important for the chemical and toxicological characteristics of raw and treated wastewater. Nevertheless, this topic has not been thoroughly investigated to date. In this study, composite wastewater samples were taken daily from the influent and effluent of a municipal sewage treatment plant. Polarity-based fractionation of the samples was carried out through sequential solid phase extractions. Biological testing of single and recombinant fractions was performed using bioluminescence inhibition assay according to DIN EN ISO 11348-2. Selected compounds (pharmaceuticals and polycyclic aromatic hydrocarbons) were also included in the chemical analysis by liquid chromatography coupled with tandem mass spectrometry and gas chromatography coupled with mass spectrometry. By analyzing different flow conditions, this study clarifies how these fractions contribute to the total toxicity of organic substances in wastewater. Additionally, it demonstrates the extent to which the potentially hazardous effects of the fractions can be reduced at the examined sewage treatment plant. Summarizing, medium to highly polar organic compounds were particularly relevant for the total toxicity of organic xenobiotics. For rising wastewater flow under wet weather conditions, we observed a significant decrease in the overall toxicity of the organic pollutants and specifically in the toxic effects of the moderately polar fraction 2. The results provide the starting point for an important risk assessment regarding the occurrence and behavior of potentially toxic xenobiotics by differentiated polarity in municipal wastewater for varying flow conditions. (orig.)

  12. Impact of L-DOPA treatment on regional cerebral blood flow and metabolism in the basal ganglia in a rat model of Parkinson's disease. (United States)

    Ohlin, K Elisabet; Sebastianutto, Irene; Adkins, Chris E; Lundblad, Cornelia; Lockman, Paul R; Cenci, M Angela


    Large increases in regional cerebral blood flow (rCBF) have been measured in patients with Parkinson's disease (PD) following the administration of L-DOPA, but the underlying mechanisms have remained unknown. In this study, rats with unilateral 6-hydroxydopamine (6-OHDA) lesions were used to compare patterns of rCBF and regional cerebral glucose utilisation (rCGU) in chronically L-DOPA-treated subjects following a final injection of L-DOPA or saline. The same animal model was used to the leakage of a blood-brain barrier (BBB) tracer molecule at 60 min vs. 24h following the last L-DOPA injection of a chronic treatment. All the parameters under investigation were examined with brain autoradiography following intravenous injections of specific radiotracers in awake animals ([14C]-iodoantipyrine for rCBF, [14C]-2-deoxyglucose for rCGU, and [14C]-α-aminoisobutyric acid for BBB leakage). Significant changes in rCBF and rCGU on the side ipsilateral to the 6-OHDA lesion relative to the non-lesioned side were seen at 60 min ("ON") but not 24h ("OFF") following L-DOPA administration. These changes were not seen in sham-operated rats. In the output nuclei of the basal ganglia (the entopeduncular nucleus and the substantia nigra pars reticulata) both rCBF and rCGU were elevated both in acutely L-DOPA-treated rats and chronically L-DOPA-treated rats displaying dyskinesia, but did not change significantly in chronically L-DOPA-treated non-dyskinetic cases. Acutely and chronically L-DOPA-treated rats with dyskinesia exhibited increases in rCBF "ON L-DOPA" also in the motor cortex, the striatum, and the globus pallidus, but the corresponding changes in rCGU did not show the same direction, magnitude, and/or relative group differences. The uptake of a BBB tracer (studied in the striatum and the substantia nigra reticulata in chronically L-DOPA treated rats) was significantly higher ON vs. OFF L-DOPA. The present results are the first to show that the administration of L-DOPA is

  13. Flow regimes

    International Nuclear Information System (INIS)

    Liles, D.R.


    Internal boundaries in multiphase flow greatly complicate fluid-dynamic and heat-transfer descriptions. Different flow regimes or topological configurations can have radically dissimilar interfacial and wall mass, momentum, and energy exchanges. To model the flow dynamics properly requires estimates of these rates. In this paper the common flow regimes for gas-liquid systems are defined and the techniques used to estimate the extent of a particular regime are described. Also, the current computer-code procedures are delineated and introduce a potentially better method is introduced

  14. Derivation and treatment of the flow wetted surface and other geosphere parameters in the transport models FARF31 and COMP23 for use in safety assessment

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Johan; Hermansson, Jan [Golder Grundteknik KB (Sweden); Elert, M.; Gylling, B. [Kemakta Konsult AB, Stockholm (Sweden); Moreno, L [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Chemical Engineering and Technology; Selroos, J.O. [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)


    This report concerns the selection of flow related transport parameters for the SR 97 safety assessment project. Interrelationships of the parameters controlling migration and matrix diffusion in the far-field and the issue of spatially varying properties along the migration paths are discussed. Available field information on porosity, flow wetted surface and dispersivity from Aberg, Beberg and Ceberg are explored and values and uncertainty ranges to be used in the assessment calculations are suggested. It is shown how to combine results from the hydrogeological modelling of SR 97 with the data estimates in order to produce parameters to the source term and far-field migration codes. Evaluation of migration and matrix diffusion along varying flow paths demonstrates that the assessment relevant parameter for migration modelling of sorbing elements is the `F-quotient`. If averaged along a flow path the F-quotient could alternatively be expressed in terms of the quotient between the `flow wetted surface per volume of rock` times the migration path length and the Darcy velocity, or as the product between water `transit time` and flow wetted surface per volume of water. In a spatially varying flow field the proper means of defining these average properties are not self evident. However, it can be shown that the sum of the F-quotient in a series of segments, where properties are constant within each segment, can be used as an effective F-quotient for the entire migration path. For non-sorbing species the F-quotient is not sufficient to describe transport. Dispersion, modelled as a Peclet number, is far less important than the F-quotient for sorbing species, at least for Peclet numbers larger than 2. The site specific transport relevant information available for the SR 97 sites comprise tracer tests, geological characterisation, hydraulic measurements, and modelling. It appears that the most defensible means of estimating the flow wetted surface per volume of rock would

  15. Potent Stimulation of Blood Flow in Fingers of Volunteers after Local Short-Term Treatment with Low-Frequency Magnetic Fields from a Novel Device

    Directory of Open Access Journals (Sweden)

    Richard H. W. Funk


    Full Text Available A novel hand-held low-frequency magnetic stimulator (MagCell-SR was tested for its ability to stimulate microcirculation in fingers of healthy volunteers. Blood flow during and after 5 minutes exposure was quantified using Laser Doppler Perfusion Imaging Technique. The device was positioned between the wrist and the dorsal part of the backhand. Because the increase in blood flow could be caused by a release of nitric oxide (NO from the vascular endothelial cells we tested NO production with a fluorescence marker and quantified the measurements in cell cultures of human umbilical endothelial cells (HUVEC. Exposure increased blood flow significantly, persisted several minutes, and then disappeared gradually. In order to assess the effect of a static magnetic field, the measurements were also carried out with the device shutoff. Here, only a small increase in blood flow was noted. The application of the rotating MagCell-SR to the HUVEC cultures leads to a rapid onset and a significant increase of NO release after 15 minutes. Thus, frequencies between 4 and 12 Hz supplied by the device improve microcirculation significantly. Therefore, this device can be used in all clinical situations where an improvement of the microcirculation is useful like in chronic wound healing deficits.

  16. Does hyperbaric oxygen treatment have the potential to increase salivary flow rate and reduce xerostomia in previously irradiated head and neck cancer patients? A pilot study

    DEFF Research Database (Denmark)

    Forner, Lone; Hansen, Ole Hyldegaard; von Brockdorff, Annet Schack


    Irradiated head and neck cancer survivors treated in the Hyperbaric Oxygen (HBO) Unit, Copenhagen University Hospital, spontaneously reported improvement of radiation-induced dry mouth feeling. The aim of this pilot study was to evaluate salivary flow rate and xerostomia before and after HBO...

  17. Amenability of European silver fir (Abies alba Mill.) to preservative treatment by the full-cell process in longitudinal, tangential, radial and triplex flow pathways on the base of wood drying

    Energy Technology Data Exchange (ETDEWEB)

    Usta, Ilker [Wood Products Industrial Engineering, Hacettepe University, 06532-Beytepe, Ankara (Turkey)


    This paper discusses the effects of wood drying upon treatability (as determined by preservative uptake and gain-in-weight retention) of European silver fir on the two moisture content (MC) levels which were designed to be above and below the fibre saturation point (FSP). The treatability behaviour was investigated for individual flow pathways: longitudinal (L, along the stem), tangential (T, along the growth rings) and radial (R, along the rays), and also for the triplex (t, cumulative of all three directions: all faces left open). As the FSP was observed 32.7%, MC of the experimental samples-for each flow path-nominated to around 50% and 9% by recommended kiln drying schedule using a conventional kiln. The samples were then treated with a 2.5% concentration of commercial Tanalith C of CCA (chromium/copper/arsenic) via a mild schedule of full-cell impregnation process using a model pressure treatment plant. Treatability of European silver fir was noticed in different behaviour in either flow paths before and after drying. According to the experimental results, MC regulate the preservative uptake (as the percentage of void volume filled with preservative, VVF%) along the grain (L) and VVF% was improved by kiln drying process effectively, however, it was seemed to be contradictory across the grain (in both T and R). In the cumulative form (t), treatability-in either above or below the FSP-was appeared to be slightly greater than that for L due to support of the longitudinal flow. Therefore, it could be suggested that wood material which is subjected to be used in constructional purposes has to be initially dried to below the FSP, and - for efficient preservative treatment - it has to be treated with all faces unsealed (free from any pre-coating and/or painting). This shall be more ideal which in turn influences the quality of treated wood allowing better performance in its service life. (author)

  18. A numerical treatment of radiative nanofluid 3D flow containing gyrotactic microorganism with anisotropic slip, binary chemical reaction and activation energy. (United States)

    Lu, Dianchen; Ramzan, M; Ullah, Naeem; Chung, Jae Dong; Farooq, Umer


    A numerical investigation of steady three dimensional nanofluid flow carrying effects of gyrotactic microorganism with anisotropic slip condition along a moving plate near a stagnation point is conducted. Additionally, influences of Arrhenius activation energy, joule heating accompanying binary chemical reaction and viscous dissipation are also taken into account. A system of nonlinear differential equations obtained from boundary layer partial differential equations is found by utilization of apposite transformations. RK fourth and fifth order technique of Maple software is engaged to acquire the solution of the mathematical model governing the presented fluid flow. A Comparison with previously done study is also made and a good agreement is achieved with existing results; hence reliable results are being presented. Evaluations are carried out for involved parameters graphically against velocity, temperature, concentration fields, microorganism distribution, density number, local Nusselt and Sherwood numbers. It is detected that microorganism distribution exhibit diminishing behavior for rising values of bio-convection Lewis and Peclet numbers.



    Noël, Xavier; Sferrazza, Rita; Van der Linden, Martial; Paternot, Jacques; Verhas, Michel; Hanak, Catherine; Pelc, Isidore; Verbanck, Paul


    — Aim: To determine whether inhibition and working memory deficits, and reduced regional cerebral blood flow (rCBF) (previously shown to be related), measured at the end of a detoxification programme, predict alcoholic relapse 2 months later. Methods: Twenty uncomplicated alcoholic inpatients were investigated at the end of detoxification, at least 7 days since the last dose of diazepam, and a mean of 18.8 days since the last drink. Their performance was assessed on the inhibition (Hayling) t...

  20. Automatic flow-batch system for cold vapor atomic absorption spectroscopy determination of mercury in honey from Argentina using online sample treatment. (United States)

    Domínguez, Marina A; Grünhut, Marcos; Pistonesi, Marcelo F; Di Nezio, María S; Centurión, María E


    An automatic flow-batch system that includes two borosilicate glass chambers to perform sample digestion and cold vapor atomic absorption spectroscopy determination of mercury in honey samples was designed. The sample digestion was performed by using a low-cost halogen lamp to obtain the optimum temperature. Optimization of the digestion procedure was done using a Box-Behnken experimental design. A linear response was observed from 2.30 to 11.20 μg Hg L(-1). The relative standard deviation was 3.20% (n = 11, 6.81 μg Hg L(-1)), the sample throughput was 4 sample h(-1), and the detection limit was 0.68 μg Hg L(-1). The obtained results with the flow-batch method are in good agreement with those obtained with the reference method. The flow-batch system is simple, allows the use of both chambers simultaneously, is seen as a promising methodology for achieving green chemistry goals, and is a good proposal to improving the quality control of honey.

  1. Static platelet adhesion, flow cytometry and serum TXB2 levels for monitoring platelet inhibiting treatment with ASA and clopidogrel in coronary artery disease: a randomised cross-over study

    Directory of Open Access Journals (Sweden)

    Hedbäck Bo


    Full Text Available Abstract Background Despite the use of anti-platelet agents such as acetylsalicylic acid (ASA and clopidogrel in coronary heart disease, some patients continue to suffer from atherothrombosis. This has stimulated development of platelet function assays to monitor treatment effects. However, it is still not recommended to change treatment based on results from platelet function assays. This study aimed to evaluate the capacity of a static platelet adhesion assay to detect platelet inhibiting effects of ASA and clopidogrel. The adhesion assay measures several aspects of platelet adhesion simultaneously, which increases the probability of finding conditions sensitive for anti-platelet treatment. Methods With a randomised cross-over design we evaluated the anti-platelet effects of ASA combined with clopidogrel as well as monotherapy with either drug alone in 29 patients with a recent acute coronary syndrome. Also, 29 matched healthy controls were included to evaluate intra-individual variability over time. Platelet function was measured by flow cytometry, serum thromboxane B2 (TXB2-levels and by static platelet adhesion to different protein surfaces. The results were subjected to Principal Component Analysis followed by ANOVA, t-tests and linear regression analysis. Results The majority of platelet adhesion measures were reproducible in controls over time denoting that the assay can monitor platelet activity. Adenosine 5'-diphosphate (ADP-induced platelet adhesion decreased significantly upon treatment with clopidogrel compared to ASA. Flow cytometric measurements showed the same pattern (r2 = 0.49. In opposite, TXB2-levels decreased with ASA compared to clopidogrel. Serum TXB2 and ADP-induced platelet activation could both be regarded as direct measures of the pharmacodynamic effects of ASA and clopidogrel respectively. Indirect pharmacodynamic measures such as adhesion to albumin induced by various soluble activators as well as SFLLRN

  2. Flow assurance

    Energy Technology Data Exchange (ETDEWEB)

    Mullins, O.C.; Dong, C. [Schlumberger-Doll Research Center, Cambridge, MA (United States); Elshahawi, H. [Shell Exploration and Production Company, The Hague (Netherlands)


    This study emphasized the need for considering flow assurance for producing oil and gas, particularly in high cost areas such as deepwater. Phase behaviour studies, sticking propensities, and interfacial interactions have been investigated in many laboratory studies using asphaltenes, wax, hydrates, organic and inorganic scale, and even diamondoids. However, the spatial variation of reservoir fluids has received little attention, despite the fact that it is one of the most important factors affecting flow assurance. This issue was difficult to address in a systematic way in the past because of cost constraints. Today, reservoir fluid variation and flow assurance can be considered at the outset of a project given the technological advances in downhole fluid analysis. This study described the origins of reservoir fluid compositional variations and the controversies surrounding them. It also described the indispensable chemical analytical technology. The impact of these reservoir fluid compositional variations on flow assurance considerations was also discussed. A methodology that accounts for these variations at the outset in flow assurance evaluation was also presented.

  3. Treatment of Cervical Internal Carotid Artery Spontaneous Dissection with Pseudoaneurysm and Unilateral Lower Cranial Nerves Palsy by Two Silk Flow Diverters

    Energy Technology Data Exchange (ETDEWEB)

    Zelenak, Kamil, E-mail: [University Hospital, Department of Radiology (Slovakia); Zelenakova, Jana [University Hospital, Department of Neurology (Slovakia); DeRiggo, Julius [University Hospital, Department of Neurosurgery (Slovakia); Kurca, Egon; Kantorova, Ema [University Hospital, Department of Neurology (Slovakia); Polacek, Hubert [University Hospital, Department of Radiology (Slovakia)


    Internal carotid artery (ICA) lesions in the parapharyngeal space (a dissection and a pseudoaneurysm) may present as isolated lower cranial nerves (IX, X, XI, and XII) palsy (Collet-Sicard syndrome). Some arteriopathies such as fibromuscular dysplasia and tortuosity make a vessel predisposed to dissection. Extreme vessel tortuosity makes the treatment by a stent graft impossible. Two Silk stents were used in a 46 year-old man with left lower cranial nerves (IX-XII) palsy for the treatment of left ICA spontaneous dissection with pseudoaneurysm. A follow-up angiogram 5 months later confirmed pseudoaneurysm thrombosis and patency of the left ICA. The patient recovered completely from the deficits.

  4. Quality control of flow cytometry data analysis for evaluation of minimal residual disease in bone marrow from acute leukemia patients during treatment

    DEFF Research Database (Denmark)

    Bjorklund, E.; Matinlauri, I.; Tierens, A.


    before implementation of MRD at cutoff level 10 as one of stratifying parameters in next Nordic Society of Pediatric Hematology and Oncology (NOPHO) treatment program for ALL. In 4 quality control (QC) rounds 15 laboratories determined the MRD levels in 48 follow-up samples from 12 ALL patients treated...

  5. Granular flow

    DEFF Research Database (Denmark)

    Mitarai, Namiko; Nakanishi, Hiizu


    Granular material is a collection of macroscopic particles that are visible with naked eyes. The non-equilibrium nature of the granular materials makes their rheology quite different from that of molecular systems. In this minireview, we present the unique features of granular materials focusing ...... on the shear flow of dry granular materials and granule-liquid mixture....

  6. Lubrication Flows. (United States)

    Papanastasiou, Tasos C.


    Discusses fluid mechanics for undergraduates including the differential Navier-Stokes equations, dimensional analysis and simplified dimensionless numbers, control volume principles, the Reynolds lubrication equation for confined and free surface flows, capillary pressure, and simplified perturbation techniques. Provides a vertical dip coating…

  7. Cerebral blood flow and glucose metabolism in appetite-related brain regions in type 1 diabetic patients after treatment with insulin detemir and NPH insulin: a randomized controlled crossover trial. (United States)

    van Golen, Larissa W; IJzerman, Richard G; Huisman, Marc C; Hensbergen, Jolanda F; Hoogma, Roel P; Drent, Madeleine L; Lammertsma, Adriaan A; Diamant, Michaela


    To test the hypothesis that insulin detemir, which is associated with less weight gain than other basal insulin formulations, exerts its weight-modulating effects by acting on brain regions involved in appetite regulation, as represented by altered cerebral blood flow (CBF) or cerebral glucose metabolism (CMRglu). Twenty-eight male type 1 diabetic patients (age 36.9 ± 9.7 years, BMI 24.9 ± 2.7 kg/m(2), A1C 7.5 ± 0.6%) successfully completed a randomized crossover study, consisting of two periods of 12-week treatment with either insulin detemir or NPH insulin, both in combination with prandial insulin aspart. After each treatment period, patients underwent positron emission tomography scans to measure regional CBF and CMRglu. After 12 weeks, A1C, daily insulin doses, fasting insulin, and blood glucose levels were similar between treatments. Insulin detemir resulted in body weight loss, whereas NPH insulin induced weight gain (between-treatment difference 1.3 kg; P = 0.02). After treatment with insulin detemir relative to NPH insulin, CBF was higher in brain regions involved in appetite regulation, whereas no significant difference in CMRglu was observed. Treatment with insulin detemir versus NPH insulin resulted in weight loss, paralleled by increased CBF in appetite-related brain regions in the resting state, in men with well-controlled type 1 diabetes. These findings lend support to the hypothesis that a differential effect on the brain may contribute to the consistently observed weight-sparing effect of insulin detemir.

  8. A Curvature Flow Unifying Symplectic Curvature Flow And Pluriclosed Flow


    Dai, Song


    Streets and Tian introduced pluriclosed flow and symplectic curvature flow in recent years. Here we construct a curvature flow to unify these two flows. We show the short time existence of our flow and exhibit an obstruction to long time existence.

  9. Stable fetal hemodynamics measured by Doppler flow after initiation of anti-hypertensive treatment with methyldopa in pregnant women with diabetes

    DEFF Research Database (Denmark)

    Pedersen, Berit Woetmann; Ringholm, Lene; Damm, Peter


     mg three times daily) was performed and the cerebro-placental ratio (CPR) was calculated. RESULTS: Methyldopa treatment was initiated at median 249 (range 192-260) gestational days, mainly due to gestational hypertension (n = 7). Blood pressure declined from 142 (112-156)/92 (76-103) mmHg before...... to 129 (108-144)/82 (75-90) mmHg after initiation of methyldopa treatment (p = 0.11 and 0.04 for systolic and diastolic blood pressure, respectively). There were no significant changes in the umbilical artery PI (0.82 (0.72-1.40) versus 0.87 (0.64-0.95), p = 0.62) or CPR (1.94 (0.96-2.33) versus 1.78 (1...

  10. Characterisation of winery wastewater from continuous flow settling basins and waste stabilisation ponds over the course of 1 year: implications for biological wastewater treatment and land application. (United States)

    Welz, P J; Holtman, G; Haldenwang, R; le Roes-Hill, M


    Wineries generate 0.2 to 4 L of wastewater per litre of wine produced. Many cellars make use of irrigation as a means of disposal, either directly or after storage. In order to consider the potential downstream impacts of storage/no storage, this study critically compared the seasonal organic and inorganic composition of fresh winery effluent with effluent that had been stored in waste stabilisation ponds. Ethanol and short chain volatile fatty acids were the main contributors to chemical oxygen demand (COD), with average concentrations of 2,086 and 882 mgCOD/L, respectively. Total phenolics were typically present in concentrations wastewater treatment by natural nitrogen supplementation. It is therefore recommended that if land requirements can be met, winery effluent should be stored in ponds prior to treatment.

  11. MHD Flow Control (United States)


    used in this analysis is based on the full 2D time-dependent Navier - Stocks equations coupled with 2D electrodynamics equation in the low magnetic...includes the treatment of chemical reacting flows on the base of full Navier - Stockes approach, chemical kinetics model, and MHD effects model...code family, PlasmAero based on full Navier -Stokes 8 equations, MHD approximation of Maxwell equations, and plasma-chemical kinetics equations is an

  12. Contribution of frontal cerebral blood flow measured by (99m)Tc-Bicisate spect and executive function deficits to predicting treatment outcome in alcohol-dependent patients. (United States)

    Noël, Xavier; Sferrazza, Rita; Van Der Linden, Martial; Paternot, Jacques; Verhas, Michel; Hanak, Catherine; Pelc, Isidore; Verbanck, Paul


    To determine whether inhibition and working memory deficits, and reduced regional cerebral blood flow (rCBF) (previously shown to be related), measured at the end of a detoxification programme, predict alcoholic relapse 2 months later. Twenty uncomplicated alcoholic inpatients were investigated at the end of detoxification, at least 7 days since the last dose of diazepam, and a mean of 18.8 days since the last drink. Their performance was assessed on the inhibition (Hayling) test, working memory (Alpha-span task), episodic memory (California Verbal Learning Test) and abstract reasoning (Progressive Matrices). Frontal CBF was assessed at the same time with a semiquantitative (99m)Tc-Bicisate SPECT procedure. Patients were contacted 2 months later. Patients who abstained (n = 9) did not differ from those who relapsed (n = 11) on age, gender, smoking, duration of alcohol misuse, number of previous detoxifications, amount of ethanol consumed the month prior to admission to the detoxification programme, state anxiety, trait anxiety, or depression. Relapsed subjects had shown a lower uptake of (99m)Tc-Bicisate in the bilateral medial frontal gyrus (n = 9; mean ratio +/- SD = 0.69 +/- 0.006) than abstainers (n = 11; 0.85 +/- 0.19), and poorer performance on the Alpha-span task and the Hayling test. The other tests were not different. Inhibition and working memory deficits, associated with low levels of CBF in the medial frontal gyrus, are related to the difficulty of maintaining short-term abstinence from alcohol.

  13. Treatment and recycling flow of copper-containing waste in Japan; Do gan`yu haikibutsu no shori to recycle no jittai

    Energy Technology Data Exchange (ETDEWEB)

    Okada, T.; Oyama, S. [The Center for Eo-mining, Tokyo (Japan); Katagiri, N.; Shimada, M.; Maeda, S. [Shinko Research Co. Ltd., Kobe (Japan)


    To clarify the downstream region of material flow (recycling and landfill), actual situation of landfill and recycling of copper, zinc and lead in all of their uses has been investigated for buildings, industrial machines, metal products with much uncertainty. This paper describes the actual situation of copper. A total of 560 thousand tons of old scrap copper were estimated to be generated as waste products. Among them, 337 thousand tons were recycled in Japan and 45 thousand tons were recycled abroad. The Residual 178 thousand tons were estimated to be landfilled. The recycling ratio of waste copper was 382/560=68.2%, being relatively high. However, this was due to 100% recovery and recycling of 197 thousand tons of cables used for power, communication and railway. The recycling ratio of waste copper except for cables was not so high, which is estimated to be increased in the future. The recycling ratio of waste industrial machines and metal products except those fixed with buildings was 21.8%, being rather low. The amount of copper recycling from buildings was estimated to be 77.4 thousand tons. 1 ref., 3 figs., 1 tab.

  14. Flow Game

    DEFF Research Database (Denmark)

    Olsen, Jesper Lind


    Flow Game er et dialogspil, der kan bruges som ledelsesværktøj, ledertræning, samtaletræning, coachingtræning og ideudvikling m.m. Gennem dilemmakort provokeres en dialog og teori-U inspireret afklaring- og udviklingsproces, hvor der enten arbejdes på en gruppes eller et individs vision/innovatio......Flow Game er et dialogspil, der kan bruges som ledelsesværktøj, ledertræning, samtaletræning, coachingtræning og ideudvikling m.m. Gennem dilemmakort provokeres en dialog og teori-U inspireret afklaring- og udviklingsproces, hvor der enten arbejdes på en gruppes eller et individs vision...

  15. Media Flow

    DEFF Research Database (Denmark)

    Kabel, Lars


    News and other kinds of journalistic stories, 16-17 hours a day, all year round, on all platforms, also the moderated social media. The key research thesis behind this article is that the continuous and speedy stream of news stories and media content now is becoming the centre of the production...... processes and the value creation in converged multimedia newsrooms. The article identify new methods and discuss editorial challenges in handling media flow....

  16. Network Flows (United States)


    n Vlog n ), which is a linear time algorithm for all but the sparsest classes of shortest path problems. 3.4. Label Correcting Algorithms Label...11962] (Programming , Games and Transportation Networks), Iri (1969] (Network Flows, Transportation and Scheduling), Hu [1969] (Integer Programming and...though the improvements are not as dramatic as they have been for E>inic’s and the FIFO preflow push algorithms. For example, the 0(nm + n^ Vlog U

  17. Development of a new non-aeration-based sewage treatment technology: Performance evaluation of a full-scale down-flow hanging sponge reactor employing third-generation sponge carriers. (United States)

    Okubo, Tsutomu; Kubota, Kengo; Yamaguchi, Takashi; Uemura, Shigeki; Harada, Hideki


    A practical-scale down-flow hanging sponge (DHS) reactor using third-generation (G3) sponge carriers was applied for treatment of the effluent from an up-flow anaerobic sludge blanket (UASB) reactor treating municipal sewage. The process performance of the DHS reactor filled with G3 sponge carriers (DHS-G3) was evaluated by conducting an on-site experiment in India over one year. The performance of the DHS-G3 for removal of organic matter and ammonium-nitrogen at a relatively short hydraulic retention time (HRT) of only 0.66 h satisfied the Indian effluent quality standards except for fecal coliform. The removal rate constants for total biochemical oxygen demand (BOD) and fecal coliform determined based on the water quality profiles along the DHS-G3 almost reached equilibrium approximately four months after the start of operation, i.e., 2.45 h(-1) for BOD and 2.30 h(-1) for fecal coliform, respectively. The oxygen utilization activity of retained sludge was determined to assess the distribution of heterotrophic and autotrophic bacteria along the DHS-G3. Nitrification was promoted in the lower portion of the DHS-G3 reactor in the duration with low organic load, while it decreased when the organic load was increased, probably due to proliferation of heterotrophic bacteria. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Woven EndoBridge Intrasaccular Flow Disrupter for the Treatment of Ruptured and Unruptured Wide-Neck Cerebral Aneurysms: Report of 55 Cases. (United States)

    Behme, D; Berlis, A; Weber, W


    The safety and efficacy of the Woven EndoBridge (WEB) device for the treatment of cerebral aneurysms have been investigated in several studies. Most of these studies focused on specific aneurysms or a certain WEB device. Our objective was to report the experience of 2 German centers with the WEB device, including technical feasibility, safety, and short-term angiographic outcome. We performed a retrospective study of all ruptured and unruptured aneurysms that were treated with a WEB device (WEB Double-Layer, Single-Layer, and Single-Layer Sphere) between April 2012 and August 2014. Primary outcome measures included the feasibility of the implantation and the angiographic outcome at 3-month follow-up. Secondary outcome measures included the clinical outcome at discharge and procedural complications. Fifty-five aneurysms in 52 patients, including 14 ruptured aneurysms, underwent treatment with the WEB device. The median age of patients was 55 years (range, 30-75 years); 19/55 (37%) were men. The device could be deployed in all patients and was implanted in 51/55 (93%) cases. Procedural complications occurred in 6/51 (12%), comprising 2 thromboembolic events, 2 thrombus formations, 1 high-grade posterior cerebral artery stenosis, and 1 aneurysm rupture. None of these had clinical sequelae. Angiographic follow-up at 3 months was available for 44/51 (86%) aneurysms. A favorable angiographic result at 3 months was achieved in 29/44 (66%) cases, whereas the percentage of good anatomic results increased from 40% in 2012 to 75% in 2014. The WEB device proved to be safe. Acceptable occlusion rates can be achieved but seem to require wide experience with the device. © 2015 by American Journal of Neuroradiology.

  19. Filamentary Flows (United States)

    Kirk, Helen


    Observations over the last few years, especially those from the Herschel Space Telescope have shown that filaments are intimately connected with dense cores. Both theory and observations are starting to suggest that filaments may provide an important reservoir of material both in the accretion of relatively isolated dense cores found along filaments, as well cluster-forming cores, which tend to be found at the junction of multiple filaments. I will review some of the recent evidence of gas flows in filaments, highlighting results from the young Serpens South cluster-forming region. I will also touch on recent analysis of numerical simulations which suggests a similar behavior.

  20. Full-Scale Modeling Explaining Large Spatial Variations of Nitrous Oxide Fluxes in a Step-Feed Plug-Flow Wastewater Treatment Reactor. (United States)

    Ni, Bing-Jie; Pan, Yuting; van den Akker, Ben; Ye, Liu; Yuan, Zhiguo


    Nitrous oxide (N2O) emission data collected from wastewater treatment plants (WWTPs) show huge variations between plants and within one plant (both spatially and temporarily). Such variations and the relative contributions of various N2O production pathways are not fully understood. This study applied a previously established N2O model incorporating two currently known N2O production pathways by ammonia-oxidizing bacteria (AOB) (namely the AOB denitrification and the hydroxylamine pathways) and the N2O production pathway by heterotrophic denitrifiers to describe and provide insights into the large spatial variations of N2O fluxes in a step-feed full-scale activated sludge plant. The model was calibrated and validated by comparing simulation results with 40 days of N2O emission monitoring data as well as other water quality parameters from the plant. The model demonstrated that the relatively high biomass specific nitrogen loading rate in the Second Step of the reactor was responsible for the much higher N2O fluxes from this section. The results further revealed the AOB denitrification pathway decreased and the NH2OH oxidation pathway increased along the path of both Steps due to the increasing dissolved oxygen concentration. The overall N2O emission from this step-feed WWTP would be largely mitigated if 30% of the returned sludge were returned to the Second Step to reduce its biomass nitrogen loading rate.

  1. Experimental Flow Characterization of a Flow Diverting Device (United States)

    Sparrow, Eph; Chow, Ricky; Campbell, Gary; Divani, Afshin; Sheng, Jian


    Flow diverters, such as the Pipeline Embolization Device, are a new class of endovascular devices for the treatment of intracranial aneurysms. While clinical studies have demonstrated safety and efficacy, their impact on intra-aneurysmal flow is not confirmed experimentally. As such, optimization of the flow diversion behavior is not currently possible. A quasi-3D PIV technique was developed and applied in various glass models at Re = 275 and 550 to determine the changes to flow characteristics due to the deployment of a flow diverter across the aneurysm neck. Outcomes such as mean velocity, wall shear stress, and others metrics will be presented. Glass models with varying radii of curvature and aneurysm locations will be examined. Experiments were performed in a fully index-matched flow facility using ~10 μm diameter polystyrene particles doped with Rhodium 6G dye. The particles were illuminated with a 532nm laser sheet and observed with a CCD camera and a 592nm +/-43 nm bandpass filter. A quasi 3D flow field was reconstructed from multiple orthogonal planes (spaced 0.4mm apart) encompassing the entire glass model. Wall stresses were evaluated from the near-wall flow viscous stresses.

  2. Towards low flow risk maps (United States)

    Blauhut, Veit; Stölzle, Michael; Stahl, Kerstin


    Drought induced low flow extremes, despite a variety of management strategies, can cause direct and indirect impacts on socio economic and ecological functions of rivers. These negative effects determine local risk and are a function of the regional drought hazard and the river system's vulnerability. Whereas drought risk analysis is known to be essential for drought management, risk analysis for low flow is less common. Where no distributed hydrological models exist, merely the local hazard at gauging stations is available to represent the entire catchment. Vulnerability information are only sparsely available. Hence, a comprehensive understanding of the drivers of low flow risk along the longitudinal river profile is often lacking. For two different rivers in southwestern Germany, this study analysed major low flow events of the past five decades. Applying a transdisciplinary approach, the hazard component is assessed by hydro-climatic analysis, hydrological modelling and forward looking stress test scenarios; the vulnerability component is estimated by a combination of impact assessment and vulnerability estimation, based on stakeholder workshops, questionnaires and regional characteristics. The results show distinct differences in low flow risk between the catchments and along the river. These differences are due to: hydrogeological characteristics that govern groundwater-surface water interaction, catchment-specific anthropogenic stimuli such as low flow decrease by near-stream groundwater pumping for public water supply or low flow augmentation by treatment plant discharge. Thus, low flow risk is anthropogenically influenced in both ways: positive and negative. Furthermore, the measured longitudinal profiles highlight the impracticability of single gauges to represent quantitative and qualitative conditions of entire rivers. Hence, this work calls for a comprehensive spatially variable consideration of flow characteristics and human influences to analyse low

  3. Impact of Routine Fractional Flow Reserve on Management Decision and 1-Year Clinical Outcome of Patients With Acute Coronary Syndromes: PRIME-FFR (Insights From the POST-IT [Portuguese Study on the Evaluation of FFR-Guided Treatment of Coronary Disease] and R3F [French FFR Registry] Integrated Multicenter Registries - Implementation of FFR [Fractional Flow Reserve] in Routine Practice). (United States)

    Van Belle, Eric; Baptista, Sergio-Bravo; Raposo, Luís; Henderson, John; Rioufol, Gilles; Santos, Lino; Pouillot, Christophe; Ramos, Ruben; Cuisset, Thomas; Calé, Rita; Teiger, Emmanuel; Jorge, Elisabete; Belle, Loic; Machado, Carina; Barreau, Didier; Costa, Marco; Hanssen, Michel; Oliveira, Eduardo; Besnard, Cyril; Costa, João; Dallongeville, Jean; Pipa, João; Sideris, Georgios; Fonseca, Nuno; Bretelle, Christophe; Guardado, Jorge; Lhoest, Nicolas; Silva, Bruno; Barnay, Pierre; Sousa, Maria-João; Leborgne, Laurent; Silva, João Carlos; Vincent, Flavien; Rodrigues, Alberto; Seca, Luís; Fernandes, Renato; Dupouy, Patrick


    Fractional flow reserve (FFR) is not firmly established as a guide to treatment in patients with acute coronary syndromes (ACS). Primary goals were to evaluate the impact of integrating FFR on management decisions and on clinical outcome of patients with ACS undergoing coronary angiography, as compared with patients with stable coronary artery disease. R3F (French FFR Registry) and POST-IT (Portuguese Study on the Evaluation of FFR-Guided Treatment of Coronary Disease), sharing a common design, were pooled as PRIME-FFR (Insights From the POST-IT and R3F Integrated Multicenter Registries - Implementation of FFR in Routine Practice). Investigators prospectively defined management strategy based on angiography before performing FFR. Final decision after FFR and 1-year clinical outcome were recorded. From 1983 patients, in whom FFR was prospectively used to guide treatment, 533 sustained ACS (excluding acute ST-segment-elevation myocardial infarction). In ACS, FFR was performed in 1.4 lesions per patient, mostly in left anterior descending (58%), with a mean percent stenosis of 58±12% and a mean FFR of 0.82±0.09. In patients with ACS, reclassification by FFR was high and similar to those with non-ACS (38% versus 39%; P =NS). The pattern of reclassification was different, however, with less patients with ACS reclassified from revascularization to medical treatment compared with those with non-ACS ( P =0.01). In ACS, 1-year outcome of patients reclassified based on FFR (FFR against angiography) was as good as that of nonreclassified patients (FFR concordant with angiography), with no difference in major cardiovascular event (8.0% versus 11.6%; P =0.20) or symptoms (92.3% versus 94.8% angina free; P =0.25). Moreover, FFR-based deferral to medical treatment was as safe in patients with ACS as in patients with non-ACS (major cardiovascular event, 8.0% versus 8.5%; P =0.83; revascularization, 3.8% versus 5.9%; P =0.24; and freedom from angina, 93.6% versus 90.2%; P =0

  4. Thermo-fluid dynamics of two-phase flow

    CERN Document Server

    Ishii, Mamoru; Ishii, Mamoru; Ishii, M


    Provides a very systematic treatment of two phase flow problems from a theoretical perspectiveProvides an easy to follow treatment of modeling and code devlopemnt of two phase flow related phenomenaCovers new results of two phase flow research such as coverage of fuel cells technology.

  5. Integrated soft sensor model for flow control. (United States)

    Aijälä, G; Lumley, D


    Tighter discharge permits often require wastewater treatment plants to maximize utilization of available facilities in order to cost-effectively reach these goals. Important aspects are minimizing internal disturbances and using available information in a smart way to improve plant performance. In this study, flow control throughout a large highly automated wastewater treatment plant (WWTP) was implemented in order to reduce internal disturbances and to provide a firm foundation for more advanced process control. A modular flow control system was constructed based on existing instrumentation and soft sensor flow models. Modules were constructed for every unit process in water treatment and integrated into a plant-wide model. The flow control system is used to automatically control recirculation flows and bypass flows at the plant. The system was also successful in making accurate flow estimations at points in the plant where it is not possible to have conventional flow meter instrumentation. The system provides fault detection for physical flow measuring devices. The module construction allows easy adaptation for new unit processes added to the treatment plant.

  6. New heavy crude oil flow improver increases delivery : application scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Pierce, J.; Johnston, R.; Lauzon, P. [ConocoPhillips Specialty Products Inc., Houston, TX (United States)


    Flow improvers or drag reducing agents have been used for over 25 years as a method to increase fluid flow in hydrocarbon pipelines. The technology is effective in refined projects, light and medium crude oils. This paper presented a new development in flow improver technology that allows treatment of heavy crude oil slates. It discussed case studies of flow improver treatment of heavy oils in various pipeline system as well as factors that affect commercial success. tabs., figs.

  7. Flow Diversion Panacea or Poison?

    Directory of Open Access Journals (Sweden)

    Mario eZanaty


    Full Text Available Endovascular therapy is now the treatment of choice for intracranial aneurysms (IAs for its efficacy and safety profile. the use of FD has recently expanded to cover many types of IAs in various locations. Some institutions even attempt FD as first line treatment for unruptured IAs. The most widely used devices are the Pipeline embolization device (PED, the SILK flow diverter (SFD, the flow redirection endoluminal device (FRED and Surpass. Many questions were raised regarding the long-term complications, the optimal regimen of dual antiplatelet therapy, and the durability of treatment effect. We reviewed the literature to address these questions as well as other concerns on FD when treating IAs.

  8. Flow of Aqueous Humor (United States)

    ... Home Flow of Aqueous Humor Flow of Aqueous Humor Most, but not all, forms of glaucoma are ... remains normal when some of the fluid (aqueous humor) produced by the eye's ciliary body flows out ...

  9. Relaminarization of fluid flows

    International Nuclear Information System (INIS)

    Narasimha, R.; Sreenivasan, K.R.


    The mechanisms of the relaminarization of turbulent flows are investigated with a view to establishing any general principles that might govern them. Three basic archetypes of reverting flows are considered: the dissipative type, the absorptive type, and the Richardson type exemplified by a turbulent boundary layer subjected to severe acceleration. A number of other different reverting flows are then considered in the light of the analysis of these archetypes, including radial Poiseuille flow, convex boundary layers, flows reverting by rotation, injection, and suction, as well as heated horizontal and vertical gas flows. Magnetohydrodynamic duct flows are also examined. Applications of flow reversion for turbulence control are discussed

  10. Synthetic Aperture Vector Flow Imaging

    DEFF Research Database (Denmark)

    Villagómez Hoyos, Carlos Armando

    The main objective of this project was to continue the development of a synthetic aperture vector flow estimator. This type of estimator is capable of overcoming two of the major limitations in conventional ultrasound systems: 1) the inability to scan large region of interest with high temporal......, this thesis showed that novel information can be obtained with vector velocity methods providing quantitative estimates of blood flow and insight into the complexity of the hemodynamics dynamics. This could give the clinician a new tool in assessment and treatment of a broad range of diseases....

  11. Modeling Vertical Flow Treatment Wetland Hydraulics to Optimize Treatment Efficiency (United States)


    other containing 20% sand, 40% peat, and 40% Bion soil, a commercially available product derived from agricultural waste (Kassenga et al., 2003). A...20% sand 40% peat and 40% Bion soil Porosity (n) 0.76±0.04 0.72±0.06 Retardation Factor (R) cDCE 3.51 TCE 2.75 1,1,1-TCA 3.69 VC 1.07 cDCE


    Energy Technology Data Exchange (ETDEWEB)

    Rieger, F. M. [ZAH, Institut für Theoretische Astrophysik, Universität Heidelberg, Philosophenweg 12, D-69120 Heidelberg (Germany); Duffy, P., E-mail:, E-mail: [University College Dublin, Belfield, Dublin 4 (Ireland)


    Shear flows are naturally expected to occur in astrophysical environments and potential sites of continuous non-thermal Fermi-type particle acceleration. Here we investigate the efficiency of expanding relativistic outflows to facilitate the acceleration of energetic charged particles to higher energies. To this end, the gradual shear acceleration coefficient is derived based on an analytical treatment. The results are applied to the context of the relativistic jets from active galactic nuclei. The inferred acceleration timescale is investigated for a variety of conical flow profiles (i.e., power law, Gaussian, Fermi–Dirac) and compared to the relevant radiative and non-radiative loss timescales. The results exemplify that relativistic shear flows are capable of boosting cosmic-rays to extreme energies. Efficient electron acceleration, on the other hand, requires weak magnetic fields and may thus be accompanied by a delayed onset of particle energization and affect the overall jet appearance (e.g., core, ridge line, and limb-brightening).

  13. Intelligent Flow Control Valve (United States)

    Kelley, Anthony R (Inventor)


    The present invention is an intelligent flow control valve which may be inserted into the flow coming out of a pipe and activated to provide a method to stop, measure, and meter flow coming from the open or possibly broken pipe. The intelligent flow control valve may be used to stop the flow while repairs are made. Once repairs have been made, the valve may be removed or used as a control valve to meter the amount of flow from inside the pipe. With the addition of instrumentation, the valve may also be used as a variable area flow meter and flow controller programmed based upon flowing conditions. With robotic additions, the valve may be configured to crawl into a desired pipe location, anchor itself, and activate flow control or metering remotely.

  14. Closing loops for material flows in surface treatment processes. Pt. 14: ecological and economic assessment and optimization. Final report and appendix; Stoffkreislaufschliessung bei abtragenden Verfahren in Prozessloesungen. Teilprojekt 14: Oekologische und oekonomische Beurteilung und Optimierung. Endbericht und Anhang

    Energy Technology Data Exchange (ETDEWEB)

    Fleischer, G.; Ackermann, R.; Scholz, C. [and others


    The industrial surface treatment of metallic and non-metallic materials is a relevant area in environmental protection. The surface-treatment industry causes polluted waste water and in addition sludges contaminated with heavy metals, which often have to be deposited as hazardous waste. Improvement of process techniques of the surface treatment is therefore an effective possibility decreasing the environmental impact. Target of this section of the research project was the ecological and economic evaluation of potential optimization possibilities for the involved enterprises and the co-operation during the optimization. For this research assignment it was determined to operate with a bottom-up methodology as in the systems analysis. The general instrument results thus as a derivative from the analysis of the methodologies with the special examples, which are processed as sample solutions. Within the framework of the work took place a use of methodical items from the LCI and the business administration. Additionally methods of process engineering and of systems analysis were applied. For the fulfillment of the target within this research assignment an objective evaluation and optimization instrument was developed and tested. With the help of this instrument it is possible to judge whether modifications on system actually reduce the ecological and economic impacts within the total system boundaries. For the support of the instrument several software-programs were used and developed. In addition, generalizable process models were elaborated and algorithms for determination and conversion to flow of material-minimizing technologies were derived and represented in generally. (orig.) [German] Die industrielle Oberflaechenbehandlung mit den zahlreichen Moeglichkeiten der Beschichtung und Abtragung von vorwiegend metallischen Werkstoffen ist ein relevanter Bereich im Umweltschutz. Es fallen neben belasteten Abwaessern auch schwermetallhaltige Schlaemme an, die oft als

  15. Hyperhomocysteinemia decreases bone blood flow

    Directory of Open Access Journals (Sweden)

    Neetu T


    Full Text Available Neetu Tyagi*, Thomas P Vacek*, John T Fleming, Jonathan C Vacek, Suresh C TyagiDepartment of Physiology and Biophysics, School of Medicine, University of Louisville, Louisville, KY, USA *These authors have equal authorshipAbstract: Elevated plasma levels of homocysteine (Hcy, known as hyperhomocysteinemia (HHcy, are associated with osteoporosis. A decrease in bone blood flow is a potential cause of compromised bone mechanical properties. Therefore, we hypothesized that HHcy decreases bone blood flow and biomechanical properties. To test this hypothesis, male Sprague–Dawley rats were treated with Hcy (0.67 g/L in drinking water for 8 weeks. Age-matched rats served as controls. At the end of the treatment period, the rats were anesthetized. Blood samples were collected from experimental or control rats. Biochemical turnover markers (body weight, Hcy, vitamin B12, and folate were measured. Systolic blood pressure was measured from the right carotid artery. Tibia blood flow was measured by laser Doppler flow probe. The results indicated that Hcy levels were significantly higher in the Hcy-treated group than in control rats, whereas vitamin B12 levels were lower in the Hcy-treated group compared with control rats. There was no significant difference in folate concentration and blood pressure in Hcy-treated versus control rats. The tibial blood flow index of the control group was significantly higher (0.78 ± 0.09 flow unit compared with the Hcy-treated group (0.51 ± 0.09. The tibial mass was 1.1 ± 0.1 g in the control group and 0.9 ± 0.1 in the Hcy-treated group. The tibia bone density was unchanged in Hcy-treated rats. These results suggest that Hcy causes a reduction in bone blood flow, which contributes to compromised bone biomechanical properties.Keywords: homocysteine, tibia, bone density

  16. Flow Element Models

    DEFF Research Database (Denmark)

    Heiselberg, Per; Nielsen, Peter V.

    Air distribution in ventilated rooms is a flow process that can be divided into different elements such as supply air jets, exhaust flows, thermal plumes, boundary layer flows, infiltration and gravity currents. These flow elements are isolated volumes where the air movement is controlled...... by a restricted number of parameters, and the air movement is fairly independent of the general flow in the enclosure. In many practical situations, the most convenient· method is to design the air distribution system using flow element theory....

  17. Dynamic power flow controllers

    Energy Technology Data Exchange (ETDEWEB)

    Divan, Deepakraj M.; Prasai, Anish


    Dynamic power flow controllers are provided. A dynamic power flow controller may comprise a transformer and a power converter. The power converter is subject to low voltage stresses and not floated at line voltage. In addition, the power converter is rated at a fraction of the total power controlled. A dynamic power flow controller controls both the real and the reactive power flow between two AC sources having the same frequency. A dynamic power flow controller inserts a voltage with controllable magnitude and phase between two AC sources; thereby effecting control of active and reactive power flows between two AC sources.

  18. Introduction to compressible fluid flow

    CERN Document Server

    Oosthuizen, Patrick H


    IntroductionThe Equations of Steady One-Dimensional Compressible FlowSome Fundamental Aspects of Compressible FlowOne-Dimensional Isentropic FlowNormal Shock WavesOblique Shock WavesExpansion Waves - Prandtl-Meyer FlowVariable Area FlowsAdiabatic Flow with FrictionFlow with Heat TransferLinearized Analysis of Two-Dimensional Compressible FlowsHypersonic and High-Temperature FlowsHigh-Temperature Gas EffectsLow-Density FlowsBibliographyAppendices

  19. Glial and neuronal control of brain blood flow

    DEFF Research Database (Denmark)

    Attwell, David; Buchan, Alastair M; Charpak, Serge


    recognized that neurotransmitter-mediated signalling has a key role in regulating cerebral blood flow, that much of this control is mediated by astrocytes, that oxygen modulates blood flow regulation, and that blood flow may be controlled by capillaries as well as by arterioles. These conceptual shifts......Blood flow in the brain is regulated by neurons and astrocytes. Knowledge of how these cells control blood flow is crucial for understanding how neural computation is powered, for interpreting functional imaging scans of brains, and for developing treatments for neurological disorders. It is now...... in our understanding of cerebral blood flow control have important implications for the development of new therapeutic approaches....

  20. Optimization of up-flow anaerobic sludge blanket reactor for ...

    African Journals Online (AJOL)

    Optimization of up-flow anaerobic sludge blanket reactor for treatment of composite fermentation and distillation wastewater. ... Keywords: Composite wastewater, up-flow anaerobic sludge blanket (UASB), anaerobic biological treatment, biogas, granulated anaerobic sludge, industrial wastewater. African Journal of ...

  1. Organocatalysis in continuous flow

    NARCIS (Netherlands)

    Berg, van den S.A.


    Continuous flow chemistry is an enabling technique in organic chemistry. Advantages include extremely fast mixing and heat transfer capabilities as well as rapid screening of reaction conditions. Combining continuous flow chemistry with solid-supported organocatalysis presents challenges that have

  2. Review of zonal flows

    International Nuclear Information System (INIS)

    Diamond, P.H.; Itoh, S.-I.; Itoh, K.; Hahm, T.S.


    A comprehensive review of zonal flow phenomena in plasmas is presented. While the emphasis is on zonal flows in laboratory plasmas, zonal flows in nature are discussed as well. The review presents the status of theory, numerical simulation and experiments relevant to zonal flows. The emphasis is on developing an integrated understanding of the dynamics of drift wave - zonal flow turbulence by combining detailed studies of the generation of zonal flows by drift waves, the back-interaction of zonal flows on the drift waves, and the various feedback loops by which the system regulates and organizes itself. The implications of zonal flow phenomena for confinement in, and the phenomena of fusion devices are discussed. Special attention is given to the comparison of experiment with theory and to identifying direction for progress in future research. (author)

  3. Practical flow cytometry

    National Research Council Canada - National Science Library

    Shapiro, Howard M


    ... ... Conflict: Resolution ... 1.3 Problem Number One: Finding The Cell(s) ... Flow Cytometry: Quick on the Trigger ... The Main Event ... The Pulse Quickens, the Plot Thickens ... 1.4 Flow Cytometry: ...

  4. Peak flow meter (image) (United States)

    A peak flow meter is commonly used by a person with asthma to measure the amount of air that can be ... become narrow or blocked due to asthma, peak flow values will drop because the person cannot blow ...

  5. Material Flow Analysis for Industrial Waste Management in Thailand


    Plubcharoensuk, Patsarporn; Nakayama, Hirofumi; Shimaoka, Takayuki; 中山, 裕文; 島岡, 隆行


    Material flow analysis (MFA) is an excellent tool in supporting decision making regarding waste management problems. MFA allows the calculation of the amount and composition of wastes by balancing the process of waste generation and the process of waste treatment. MFA can be used to analyze wastes flow because inputs-outputs of waste treatment can be linked. The industrial waste management system in Thailand is still lacking comprehensive data on industrial waste generation and flow. Therefor...

  6. Load flow optimization and optimal power flow

    CERN Document Server

    Das, J C


    This book discusses the major aspects of load flow, optimization, optimal load flow, and culminates in modern heuristic optimization techniques and evolutionary programming. In the deregulated environment, the economic provision of electrical power to consumers requires knowledge of maintaining a certain power quality and load flow. Many case studies and practical examples are included to emphasize real-world applications. The problems at the end of each chapter can be solved by hand calculations without having to use computer software. The appendices are devoted to calculations of line and cable constants, and solutions to the problems are included throughout the book.

  7. Hyperspectral imaging flow cytometer (United States)

    Sinclair, Michael B.; Jones, Howland D. T.


    A hyperspectral imaging flow cytometer can acquire high-resolution hyperspectral images of particles, such as biological cells, flowing through a microfluidic system. The hyperspectral imaging flow cytometer can provide detailed spatial maps of multiple emitting species, cell morphology information, and state of health. An optimized system can image about 20 cells per second. The hyperspectral imaging flow cytometer enables many thousands of cells to be characterized in a single session.

  8. Granular media : flow & agitations

    NARCIS (Netherlands)

    Dijksman, Joshua Albert


    This thesis is about weakly driven granular flows and suspensions. Chapter 1 is an overview of the current knowledge of slow granular flows in so-called split-bottom geometries, which in essence consist of a disk rotating at the bottom of a container. In chapter 2 we study dry granular flows in this

  9. OpenFlow cookbook

    CERN Document Server

    Smiler S, Kingston


    This book is intended for network protocol developers, SDN controller application developers, and academics who would like to understand and develop their own OpenFlow switch or OpenFlow controller in any programming language. With basic understanding of OpenFlow and its components, you will be able to follow the recipes in this book.

  10. Thermal flow micro sensors

    NARCIS (Netherlands)

    Elwenspoek, Michael Curt


    A review is given on sensors fabricated by silicon micromachining technology using the thermal domain for the measurement of fluid flow. Attention is paid especially to performance and geometry of the sensors. Three basic types of thermal flow sensors are discussed: anemometers, calorimetric flow

  11. A Study of Flow in Entrepreneurs


    Woodruff, Timothy James


    What is the experience of flow like in Entrepreneurs? This work defines the concept of an entrepreneur, discusses that concept in regards to creativity, and accesses the impact Flow has on entrepreneurial behaviour. Within entrepreneurship theory and cognitive theories of creativity extensive research has been performed. However, the experience of entrepreneurship itself has had no such treatment. Most authors recognise the role that creativity plays in entrepreneurship, and, within that clai...

  12. Operação de Blalock-Taussig modificada para o tratamento paliativo de cardiopatias congênitas com hipofluxo pulmonar Blalock-Taussig operation for palliative treatment of congenital heart disease with low pulmonary flow

    Directory of Open Access Journals (Sweden)

    Miguel A Maluf


    úrgica. A operação de Blalock-Taussig modificada demonstrou ser um método confiável e seguro no tratamento paliativo das cardiopatias com hipofluxo pulmonarFrom January 1990 to November 1994, 72 patients with congenital heart defects and low pulmonary flow underwent modified Blalock-Taussig produce. There were 44 (61.1% males and 28 (38.8% females with ages ranging from 2 days to 11 years (average 9 months. Thirty eight (52,8% patients had Tetralogy of Fallot; 7 (9,7% had pulmonary atresia with intact ventricular septum (PA/IVS; 6 (8.4%, had transposition of the great arteries (TGA with pulmonary stenosis (PS; 6 (8,4% had tricuspid atresia (TA with PS; 6 (8.4% had double inlet of right ventricle (RV or left ventricle (LV and PS; 3 (4.2% had corrected transposition of the great arteries (CTGA with ventricular septal defects (VSD and PS; 2 (2.7% had double outlet of RV or LV and PS; 2 (2.7% had atrio-ventricular canal defects (A-VC and PS; 2 (2.7% patients had right or left Isomerism and PS. The decision to surgical indication was based on: a new borns with "ductus dependent" heart defects; b lactents with important cianosis or hypoxia; c infants with heart defects without possibilities of biventricular correction. The surgical technique employed was the Blalock-Taussig operation using 4 or 5 mm Polytetrafluoroethy (PTFE prosthesis in 69 (94.5% cases, umbilical vein in 3 (4.1% cases and bovine thoracic artery in 1 (1.4% case. Before the arteries were clamped 1 mg/kg of héparine was given without mobilization, with protamine, after the procedure. During the post-operative period, anticoagulants were not given. The prosthesis obstruction was the main cause of death and was related to artery anatomy: subclavian and pulmonary artery diameter and/or problems with the technique. The modified Blalock-Taussig operation showed itself to be a reliable palliative treatment to heart defects with low pulmonary flow

  13. Separation of flow

    CERN Document Server

    Chang, Paul K


    Interdisciplinary and Advanced Topics in Science and Engineering, Volume 3: Separation of Flow presents the problem of the separation of fluid flow. This book provides information covering the fields of basic physical processes, analyses, and experiments concerning flow separation.Organized into 12 chapters, this volume begins with an overview of the flow separation on the body surface as discusses in various classical examples. This text then examines the analytical and experimental results of the laminar boundary layer of steady, two-dimensional flows in the subsonic speed range. Other chapt

  14. Signal flow analysis

    CERN Document Server

    Abrahams, J R; Hiller, N


    Signal Flow Analysis provides information pertinent to the fundamental aspects of signal flow analysis. This book discusses the basic theory of signal flow graphs and shows their relation to the usual algebraic equations.Organized into seven chapters, this book begins with an overview of properties of a flow graph. This text then demonstrates how flow graphs can be applied to a wide range of electrical circuits that do not involve amplification. Other chapters deal with the parameters as well as circuit applications of transistors. This book discusses as well the variety of circuits using ther

  15. Lateral flow strip assay (United States)

    Miles, Robin R [Danville, CA; Benett, William J [Livermore, CA; Coleman, Matthew A [Oakland, CA; Pearson, Francesca S [Livermore, CA; Nasarabadi, Shanavaz L [Livermore, CA


    A lateral flow strip assay apparatus comprising a housing; a lateral flow strip in the housing, the lateral flow strip having a receiving portion; a sample collection unit; and a reagent reservoir. Saliva and/or buccal cells are collected from an individual using the sample collection unit. The sample collection unit is immersed in the reagent reservoir. The tip of the lateral flow strip is immersed in the reservoir and the reagent/sample mixture wicks up into the lateral flow strip to perform the assay.

  16. Annular Flow Distribution test

    Energy Technology Data Exchange (ETDEWEB)

    Kielpinski, A.L. (ed.) (Westinghouse Savannah River Co., Aiken, SC (United States)); Childerson, M.T.; Knoll, K.E.; Manolescu, M.I.; Reed, M.J. (Babcock and Wilcox Co., Alliance, OH (United States). Research Center)


    This report documents the Babcock and Wilcox (B W) Annular Flow Distribution testing for the Savannah River Laboratory (SRL). The objective of the Annular Flow Distribution Test Program is to characterize the flow distribution between annular coolant channels for the Mark-22 fuel assembly with the bottom fitting insert (BFI) in place. Flow rate measurements for each annular channel were obtained by establishing hydraulic similarity'' between an instrumented fuel assembly with the BFI removed and a reference'' fuel assembly with the BFI installed. Empirical correlations of annular flow rates were generated for a range of boundary conditions.

  17. Annular Flow Distribution test

    International Nuclear Information System (INIS)

    Kielpinski, A.L.; Childerson, M.T.; Knoll, K.E.; Manolescu, M.I.; Reed, M.J.


    This report documents the Babcock and Wilcox (B ampersand W) Annular Flow Distribution testing for the Savannah River Laboratory (SRL). The objective of the Annular Flow Distribution Test Program is to characterize the flow distribution between annular coolant channels for the Mark-22 fuel assembly with the bottom fitting insert (BFI) in place. Flow rate measurements for each annular channel were obtained by establishing ''hydraulic similarity'' between an instrumented fuel assembly with the BFI removed and a ''reference'' fuel assembly with the BFI installed. Empirical correlations of annular flow rates were generated for a range of boundary conditions

  18. Physics of zonal flows

    International Nuclear Information System (INIS)

    Itoh, K.; Fujisawa, A.; Itoh, S.-I.; Yagi, M.; Nagashima, Y.; Diamond, P.H.; Tynan, G.R.; Hahm, T.S.


    Zonal flows, which means azimuthally symmetric band-like shear flows, are ubiquitous phenomena in nature and the laboratory. It is now widely recognized that zonal flows are a key constituent in virtually all cases and regimes of drift wave turbulence, indeed, so much so that this classic problem is now frequently referred to as ''drift wave-zonal flow turbulence.'' In this review, new viewpoints and unifying concepts are presented, which facilitate understanding of zonal flow physics, via theory, computation and their confrontation with the results of laboratory experiment. Special emphasis is placed on identifying avenues for further progress. (author)


    NARCIS (Netherlands)



    In a comparative cross-over trial we examined the influence of the betablocker bisoprolol and the ACE-inhibitor lisinopril on the peripheral blood flow of 2 groups of hypertensive patients with and without concomitant intermittent claudication. In 11 patients with hypertension without peripheral

  20. Cerebral Blood Flow and Glucose Metabolism in Appetite-Related Brain Regions in Type 1 Diabetic Patients After Treatment With Insulin Detemir and NPH Insulin A randomized controlled crossover trial

    NARCIS (Netherlands)

    van Golen, L.W.; IJzerman, R.G.; Huisman, M.C.; Hensbergen, J.F.; Hoogma, R.P.; Drent, M.L.; Lammertsma, A.A.; Diamant, M.


    Objective-To test the hypothesis that insulin detemir, which is associated with less weight gain than other basal insulin formulations, exerts its weight-modulating effects by acting on brain regions involved in appetite regulation, as represented by altered cerebral blood flow (CBF) or cerebral

  1. Simulation and modeling of turbulent flows

    CERN Document Server

    Gatski, Thomas B; Lumley, John L


    This book provides students and researchers in fluid engineering with an up-to-date overview of turbulent flow research in the areas of simulation and modeling. A key element of the book is the systematic, rational development of turbulence closure models and related aspects of modern turbulent flow theory and prediction. Starting with a review of the spectral dynamics of homogenous and inhomogeneous turbulent flows, succeeding chapters deal with numerical simulation techniques, renormalization group methods and turbulent closure modeling. Each chapter is authored by recognized leaders in their respective fields, and each provides a thorough and cohesive treatment of the subject.

  2. Alterations in whole saliva flow rate induced by fractionated radiotherapy

    International Nuclear Information System (INIS)

    Wescott, W.B.; Mira, J.G.; Starcke, E.N.; Shannon, I.L.; Thornby, J.L.


    Sequential changes in flow rate of whole saliva are detailed in 13 patients. Samples were collected without exogenous stimulation during a course of fractionated radiotherapy involving major portions of the salivary glands. Flow rate decreased markedly during the initial 3 treatment days and gradually thereafter until a minimal flow rate was reached. Early in the treatment, variable degrees of recovery were seen on Mondays following a weekend (Friday-Sunday) without treatment. After a minimal flow rate was reached, no such recovery was observed. Radiation needed to produce minimal flow varied from 450 to 4,050 rad. Patients with higher initial flow rates required higher dosages to reach the minimum. No return of secretory function was noted after extended periods of time

  3. Alterations in whole saliva flow rate induced by fractionated radiotherapy. (United States)

    Wescott, W B; Mira, J G; Starcke, E N; Shannon, I L; Thornby, J I


    Sequential changes in flow rate of whole saliva are detailed in 13 patients. Samples were collected without exogneous stimulation during a course of fractionated radiotherapy involving major portions of the salivary glands. Flow rate decreased markedly during the initial 3 treatment days and gradually thereafter until a minimal flow rate was reached. Early in the treatment, variable degrees of recovery were seen on Mondays following a weekend (Friday-Sunday) without treatment. After a minimal flow rate was reached, no such recovery was observed. Radiation needed to produce minimal flow varied from 450 to 4,050 rad. Patients with higher initial flow rates required higher dosages to reach the minimum. No return of secretory function was noted after extended periods of time.

  4. 46 CFR 154.546 - Excess flow valve: Closing flow. (United States)


    ... 46 Shipping 5 2010-10-01 2010-10-01 false Excess flow valve: Closing flow. 154.546 Section 154.546... and Process Piping Systems § 154.546 Excess flow valve: Closing flow. (a) The rated closing flow of vapor or liquid cargo for an excess flow valve must be specially approved by the Commandant (CG-522). (b...

  5. Group flow, complex flow, unit vector flow, and the (2+ϵ)-flow conjecture

    DEFF Research Database (Denmark)

    Thomassen, Carsten


    If F is a (possibly infinite) subset of an abelian group Γ, then we define f(F,Γ) as the smallest natural number such that every f(F,Γ)-edge-connected (finite) graph G has a flow where all flow values are elements in F. We prove that f(F,Γ) exists if and only if some odd sum of elements in F equals...... some even sum. We discuss various instances of this problem. We prove that every 6-edge-connected graph has a flow whose flow values are the three roots of unity in the complex plane. If the edge-connectivity 6 can be reduced, then it can be reduced to 4, and the 3-flow conjecture follows. We prove...... that every 14-edge-connected graph has a flow whose flow values are the five roots of unity in the complex plane. Any such flow is balanced modulo 5. So, if the edge-connectivity 14 can be reduced to 9, then the 5-flow conjecture follows, as observed by F. Jaeger. We use vector flow to prove that, for each...

  6. CRADA final report: Technical assessment of roll-to-roll operation of lamination process, thermal treatment, and alternative carbon fiber precursors for low-cost, high-efficiency manufacturing of flow battery stacks and other energy devices

    Energy Technology Data Exchange (ETDEWEB)

    Daniel, Claus [ORNL; Madden, Thomas [Lockheed Martin Corporation; Wood III, David L [ORNL; Muth, Thomas R [ORNL; Warrington, Curtis [Lockheed Martin Corporation; Ozcan, Soydan [ORNL; Manson, Hunter [Oak Ridge National Laboratory (ORNL); Tekinalp, Halil L [ORNL; Smith, Mark A [ORNL; Lu, Yuan [ORNL; Loretz, Jeremy [Oak Ridge National Laboratory (ORNL)


    Among the various stationary-storage technologies under development, redox flow batteries (RFBs) offer the greatest potential to deliver inexpensive, scalable, and efficient grid-scale electrical-energy storage. Unlike traditional sealed batteries, in a flow battery power and energy are decoupled. Cell area and cell count in the stack determine the device power, and the chemical storage volume determines the total energy. Grid-scale energy-storage applications require megawatt-scale devices, which require the assembly of hundreds of large-area, bipolar cells per power plant. The cell-stack is the single system component with the largest impact on capital cost (due to the large number of highly engineered components) and operating costs (determined by overall round-trip efficiency).

  7. Comment on the treatment of residual water content in “A consistent set of parametric models for the two-phase flow of immiscible fluids in the subsurface” by L. Luckner et al. (United States)

    Nimmo, John R.


    Luckner et al. [1989] (hereinafter LVN) present a clear summary and generalization of popular formulations used for convenient representation of porous media fluid flow characteristics, including water content (θ) related to suction (h) and hydraulic conductivity (K) related to θ or h. One essential but problematic element in the LVN models is the concept of residual water content (θr; in LVN, θw,r). Most studies using θr determine its value as a fitted parameter and make the assumption that liquid flow processes are negligible at θ values less than θr. While the LVN paper contributes a valuable discussion of the nature of θr, it leaves several problems unresolved, including fundamental difficulties in associating a definite physical condition with θr, practical inadequacies of the models at low θ values, and difficulties in designating a main wetting curve.

  8. Design flow factors for sewerage systems in small arid communities

    Directory of Open Access Journals (Sweden)

    Emad H. Imam


    Full Text Available Reliable estimation of sewage flow rates is essential for the proper design of sewers, pumping stations, and treatment plants. The design of the various components of the sewerage system should be based on the most critical flow rates with a focus on extremely low and peak flow rates that would be sustained for a duration related to the acceptable limits of behavior of the components under consideration. The extreme flow conditions and to what extent they differ from the average values are closely related to the size of the community or network, and the socioeconomic conditions. A single pumping station is usually sufficient to pump flow from small community in either flat or non-undulating topography. Therefore, the hydraulic loading on the wastewater treatment plant (WWTP results from the pumped flow from the pumping station rather than the trunk sewer flow. The intermittent operation of the pumping units further accentuates the sewage hydrograph in the final trunk sewer. Accordingly, the design flow for the various components of the WWTP should be determined based on their relevant flow factors. In this study, analysis of one representative small community out of five monitored small communities in Egypt and the Kingdom of Saudi Arabia is presented. Pumped sewage flow rates were measured and the sewer incoming flows were hydraulically derived. The hourly and daily sewer and pumped flow records were analyzed to derive the relationship between the flow factors that would be sustained for various durations (instantaneously, 1 h, 2 h, etc. and their probability of non-exceedance. The resulting peaking factors with a consideration for their sustained flow duration and specified probability would permit the design of the various components of the treatment plant using more accurate critical flows.

  9. Design flow factors for sewerage systems in small arid communities. (United States)

    Imam, Emad H; Elnakar, Haitham Y


    Reliable estimation of sewage flow rates is essential for the proper design of sewers, pumping stations, and treatment plants. The design of the various components of the sewerage system should be based on the most critical flow rates with a focus on extremely low and peak flow rates that would be sustained for a duration related to the acceptable limits of behavior of the components under consideration. The extreme flow conditions and to what extent they differ from the average values are closely related to the size of the community or network, and the socioeconomic conditions. A single pumping station is usually sufficient to pump flow from small community in either flat or non-undulating topography. Therefore, the hydraulic loading on the wastewater treatment plant (WWTP) results from the pumped flow from the pumping station rather than the trunk sewer flow. The intermittent operation of the pumping units further accentuates the sewage hydrograph in the final trunk sewer. Accordingly, the design flow for the various components of the WWTP should be determined based on their relevant flow factors. In this study, analysis of one representative small community out of five monitored small communities in Egypt and the Kingdom of Saudi Arabia is presented. Pumped sewage flow rates were measured and the sewer incoming flows were hydraulically derived. The hourly and daily sewer and pumped flow records were analyzed to derive the relationship between the flow factors that would be sustained for various durations (instantaneously, 1 h, 2 h, etc.) and their probability of non-exceedance. The resulting peaking factors with a consideration for their sustained flow duration and specified probability would permit the design of the various components of the treatment plant using more accurate critical flows.

  10. Nutrient and nonnutrient renal blood flow

    International Nuclear Information System (INIS)

    Young, J.S.; Passmore, J.C.; Hartupee, D.A.; Baker, C.H.


    The role of prostaglandins in the distribution of total renal blood flow (TRBF) between nutrient and nonnutrient compartments was investigated in anesthetized mongrel dogs. Renal blood flow distribution was assessed by the xenon 133 freeze-dissection technique and by rubidium 86 extraction after ibuprofen treatment. Ibuprofen (13 mg/kg) significantly decreased TRBF by 16.3% +/- 1.2% (mean +/- SEM electromagnetic flow probe; p less than 0.005), but did not alter blood flows to the outer cortex (3.7 vs 4.3 ml/min per gram), the inner cortex (2.6 vs 2.7 ml/min per gram), and the other medulla (1.5 vs 1.5 ml/min per gram), which suggests a decrease in nonnutrient flow. In a separate group of animals the effect of reduced blood flow on the nutrient and nonnutrient components was determined by mechanically reducing renal arterial blood flow by 48%. Unlike the ibuprofen group, nutrient blood flows were proportionally reduced with the mechanical decrease in TRBF in the outer cortex (1.9 ml/min per gram, p less than 0.05), the inner cortex (1.4 ml/min per gram, p less than 0.05), and the outer medulla (0.8 ml/min per gram, p less than 0.01). These results indicate no shift between nutrient and nonnutrient compartments. Nutrient and nonnutrient renal blood flows of the left kidney were also determined by 86Rb extraction. After ibuprofen treatment, nonextracted 86Rb decreased to 12.1% from the control value of 15.6% (p less than 0.05). Mechanical reduction of TRBF did not significantly decrease the proportion of unextracted 86Rb (18.7%)

  11. A neural flow estimator

    DEFF Research Database (Denmark)

    Jørgensen, Ivan Harald Holger; Bogason, Gudmundur; Bruun, Erik


    This paper proposes a new way to estimate the flow in a micromechanical flow channel. A neural network is used to estimate the delay of random temperature fluctuations induced in a fluid. The design and implementation of a hardware efficient neural flow estimator is described. The system...... is implemented using switched-current technique and is capable of estimating flow in the μl/s range. The neural estimator is built around a multiplierless neural network, containing 96 synaptic weights which are updated using the LMS1-algorithm. An experimental chip has been designed that operates at 5 V...

  12. Responses of prawn to water flow rates

    Energy Technology Data Exchange (ETDEWEB)

    Vascotto, G.L.; Nilas, P.U.


    An aquarium study to determine the responses of postlarval macrobrachium rosenbergii to varying water changes was carried out. Six week old postlarvae were raised in glass aquaria receiving 0, 1.15, 7.2 and 14.4 water changes per day over a 12 week period. The treatments had significant influences on survival, biomass, and average size of the animals. Maximum survival and highest biomass were found in the 1.15 water turnover treatment; however, this treatment also produced the smallest average size animals. Early high mortalities were attributed to poor growing conditions in the high and low flow treatments, while later mortality appeared to be biomass dependent.

  13. Treatment Option Overview (Vaginal Cancer) (United States)

    ... Nearby lymph nodes are also removed. Artificial openings ( stoma ) are made for urine and stool to flow ... information on cancer prevention, detection, genetics, treatment, supportive care, and complementary and alternative medicine. Most summaries come ...

  14. Treatment Option Overview (Vulvar Cancer) (United States)

    ... nearby lymph nodes are also removed. Artificial openings ( stoma ) are made for urine and stool to flow ... information on cancer prevention, detection, genetics, treatment, supportive care, and complementary and alternative medicine. Most summaries come ...

  15. Flow visualization using bubbles

    International Nuclear Information System (INIS)

    Henry, J.P.


    Soap bubbles were used for visualizing flows. The tests effected allowed some characteristics of flows around models in blow tunnels to be precised at mean velocities V 0 5 . The velocity of a bubble is measured by chronophotography, the bulk envelope of the trajectories is also registered [fr

  16. Airport Network Flow Simulator (United States)


    The Airport Network Flow Simulator is a FORTRAN IV simulation of the flow of air traffic in the nation's 600 commercial airports. It calculates for any group of selected airports: (a) the landing and take-off (Type A) delays; and (b) the gate departu...

  17. Flow cytometry protocols

    National Research Council Canada - National Science Library

    Jaroszeski, Mark J; Heller, Richard


    ... are individually analyzed, and it is typical for flow cytometers to quantitatively process thousands of individual particles in a matter of seconds. This a powerful analytic feat particularly if one relates it to the time required to examine several thousand individual cells using a microscope. This leaves little doubt regarding why the field of flow cytometry has...

  18. Flow Around Steep Topography (United States)


    Flow around steep topography T. M. Shaun Johnston Scripps Institution of Oceanography University of California, San Diego 9500 Gilman Drive, M...tall, steep, submarine topography and islands. During the Flow Encountering Abrupt Topography (FLEAT) DRI, investigators will determine: • Whether...estimates from making accurate statistical/deterministic predictions at ᝺ km resolution around submarine topography and islands? How can we

  19. Biomimetic Flow Sensors

    NARCIS (Netherlands)

    Casas, J.; Liu, Chang; Krijnen, Gijsbertus J.M.


    Biomimetic flow sensors are biologically inspired devices that measure the speed and direction of fluids. This survey starts by describing the role and functioning of airflow-sensing hairs in arthropods and in fishes, carries on with the biomimetic MEMS implementations, both for air and water flow

  20. Flow og anerkendelse

    DEFF Research Database (Denmark)

    Kristensen, René


    Artiklen handler om pædagogisk perspektivering af flow i forhold til anerkendelse og kreativitet. Procedural hukommelsesdannelse inddrages i forbindelse med flowforståelsen......Artiklen handler om pædagogisk perspektivering af flow i forhold til anerkendelse og kreativitet. Procedural hukommelsesdannelse inddrages i forbindelse med flowforståelsen...

  1. Flow i hverdagen

    DEFF Research Database (Denmark)

    Andersen, Frans Ørsted; Hanssen, Nina

    Bogen afspejler et eksplorativt dansk-norsk forskningsprojekt med fokus på hverdagslivets psykiske sider, herunder størrelser som stress og flow.......Bogen afspejler et eksplorativt dansk-norsk forskningsprojekt med fokus på hverdagslivets psykiske sider, herunder størrelser som stress og flow....

  2. Delays of Interconnected Flows (United States)

    Sorger, U.; Suchanecki, Z.


    A rigorous approach to flows of particles in networks is presented. Under the assumption of independence of the transversal flows the asymptotic distributions of inter-delay times between particles are shown to be log-normal. In the case of dependent transversal traffic the ARCH and GARCH time series models, as well as martingale approach, have been applied.

  3. AUTO-EXPANSIVE FLOW (United States)

    Physics suggests that the interplay of momentum, continuity, and geometry in outward radial flow must produce density and concomitant pressure reductions. In other words, this flow is intrinsically auto-expansive. It has been proposed that this process is the key to understanding...

  4. Improved modeling techniques for turbomachinery flow fields

    Energy Technology Data Exchange (ETDEWEB)

    Lakshminarayana, B.; Fagan, J.R. Jr.


    This program has the objective of developing an improved methodology for modeling turbomachinery flow fields, including the prediction of losses and efficiency. Specifically, the program addresses the treatment of the mixing stress tensor terms attributed to deterministic flow field mechanisms required in steady-state Computational Fluid Dynamic (CFD) models for turbomachinery flow fields. These mixing stress tensors arise due to spatial and temporal fluctuations (in an absolute frame of reference) caused by rotor-stator interaction due to various blade rows and by blade-to-blade variation of flow properties. This will be accomplished in a cooperative program by Penn State University and the Allison Engine Company. These tasks include the acquisition of previously unavailable experimental data in a high-speed turbomachinery environment, the use of advanced techniques to analyze the data, and the development of a methodology to treat the deterministic component of the mixing stress tenor.

  5. Optimised Renormalisation Group Flows

    CERN Document Server

    Litim, Daniel F


    Exact renormalisation group (ERG) flows interpolate between a microscopic or classical theory and the corresponding macroscopic or quantum effective theory. For most problems of physical interest, the efficiency of the ERG is constrained due to unavoidable approximations. Approximate solutions of ERG flows depend spuriously on the regularisation scheme which is determined by a regulator function. This is similar to the spurious dependence on the ultraviolet regularisation known from perturbative QCD. Providing a good control over approximated ERG flows is at the root for reliable physical predictions. We explain why the convergence of approximate solutions towards the physical theory is optimised by appropriate choices of the regulator. We study specific optimised regulators for bosonic and fermionic fields and compare the optimised ERG flows with generic ones. This is done up to second order in the derivative expansion at both vanishing and non-vanishing temperature. An optimised flow for a ``proper-time ren...

  6. Mere om flow

    DEFF Research Database (Denmark)

    Wohlgemuth, Ole


    "Begrebet flow, som det er formuleret af den ungarskefødte, amerikanske psykolog Mihaly Csikszentmihalyi", "beskriver en koncentreret tilstand af opslugthed i forbindelse med en oplevelse eller aktivitet. Flow betragtes som den tilstand, hvor læring foregår mest meningsfuldt, intensivt og...... grundlæggende; flow er endog blevet beskrevet som "de positive følelser kroppen belønner os med, når vi lærer noget vigtigt". Flow har sit udspring i positiv psykologi, som er et begreb indenfor den psykologiske forskning, der fokuserer på spørgsmålet om, hvad skal der til for at mennesker og samfund bedre kan...... trives og blomstre frem for et fokus på sygdomsfremkaldende og negative sammenhænge." ... "flow er en væsentlig tilstand at være fokuseret på og arbejde mod i forbindelse med formidling af naturen."...

  7. Vega flow assurance system

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, Marit; Munaweera, Sampath


    Vega is a gas condensate field located at the west coast of Norway and developed as a tie-in to the Gjoea platform. Operator is Statoil, production startup is estimated to the end of 2010. Flow assurance challenges are high reservoir pressure and temperature, hydrate and wax control, liquid accumulation and monitoring the well/template production rates. The Vega Flow Assurance System (FAS) is a software that supports monitoring and operation of the field. The FAS is based FlowManagerTM designed for real time systems. This is a flexible tool with its own steady state multiphase- and flow assurance models. Due to the long flowlines lines and the dynamic behavior, the multiphase flow simulator OLGA is also integrated in the system. Vega FAS will be used as: - An online monitoring tool - An offline what-if simulation and validation tool - An advisory control system for well production allocation. (Author)

  8. Environmental stratified flows

    CERN Document Server

    Armenio, Vincenzo


    The volume covers the theory of stratified flows, from basic concepts to recent developments in the area of environmental fluid mechanics. The state of art of numerical techniques suited for stratified flows is given. Results of very recent researches in the areas of environmental stratified flows are discussed with details. The topics are treated in four separate chapters. The volume gives a unified view of stratified turbulent flows, from small-scale mixing, to large-scale environmental phenomena, also including detailed discussion on interaction between turbulence and internal gravity waves. The book will serve as an important review tool for all the scientists involved in the investigation of small scale as well as geophysical stratified flows.

  9. Flow regime analysis of non-Newtonian duct flows (United States)

    Speetjens, Michel; Rudman, Murray; Metcalfe, Guy


    Reoriented duct flows of generalized Newtonian fluids are an idealization of non-Newtonian fluid flow in industrial in-line mixers. Based on scaling analysis and computation we find that non-Newtonian duct flows have several limit behaviors, in the sense that such flows can become (nearly) independent of one or more of the rheological and dynamical control parameters, simplifying the general flow and mixing problem. These limit flows give several levels of modeling complexity to the full problem of non-Newtonian duct flow. We describe the sets of simplified flow models and their corresponding regions of validity. This flow-model decomposition captures the essential rheological and dynamical characteristics of the reoriented duct flows and enables a more efficient and systematic study and design of flow and mixing of non-Newtonian fluids in ducts. Key aspects of the flow-model decomposition are demonstrated via a specific, but representative, duct flow.

  10. Flow in bedrock canyons. (United States)

    Venditti, Jeremy G; Rennie, Colin D; Bomhof, James; Bradley, Ryan W; Little, Malcolm; Church, Michael


    Bedrock erosion in rivers sets the pace of landscape evolution, influences the evolution of orogens and determines the size, shape and relief of mountains. A variety of models link fluid flow and sediment transport processes to bedrock incision in canyons. The model components that represent sediment transport processes are increasingly well developed. In contrast, the model components being used to represent fluid flow are largely untested because there are no observations of the flow structure in bedrock canyons. Here we present a 524-kilometre, continuous centreline, acoustic Doppler current profiler survey of the Fraser Canyon in western Canada, which includes 42 individual bedrock canyons. Our observations of three-dimensional flow structure reveal that, as water enters the canyons, a high-velocity core follows the bed surface, causing a velocity inversion (high velocities near the bed and low velocities at the surface). The plunging water then upwells along the canyon walls, resulting in counter-rotating, along-stream coherent flow structures that diverge near the bed. The resulting flow structure promotes deep scour in the bedrock channel floor and undercutting of the canyon walls. This provides a mechanism for channel widening and ensures that the base of the walls is swept clear of the debris that is often deposited there, keeping the walls nearly vertical. These observations reveal that the flow structure in bedrock canyons is more complex than assumed in the models presently used. Fluid flow models that capture the essence of the three-dimensional flow field, using simple phenomenological rules that are computationally tractable, are required to capture the dynamic coupling between flow, bedrock erosion and solid-Earth dynamics.

  11. Stabilization of Navier-Stokes flows

    CERN Document Server

    Barbu, Viorel


    This volume presents recent and notable progress in the mathematical theory of stabilization of Newtonian fluid flows. It avoids the tedious technical details often seen in mathematical treatments of the subject and will thus appeal to a wide range of readers.

  12. Lava flows are fractals (United States)

    Bruno, B. C.; Taylor, G. J.; Rowland, S. K.; Lucey, P. G.; Self, S.


    Results are presented of a preliminary investigation of the fractal nature of the plan-view shapes of lava flows in Hawaii (based on field measurements and aerial photographs), as well as in Idaho and the Galapagos Islands (using aerial photographs only). The shapes of the lava flow margins are found to be fractals: lava flow shape is scale-invariant. This observation suggests that nonlinear forces are operating in them because nonlinear systems frequently produce fractals. A'a and pahoehoe flows can be distinguished by their fractal dimensions (D). The majority of the a'a flows measured have D between 1.05 and 1.09, whereas the pahoehoe flows generally have higher D (1.14-1.23). The analysis is extended to other planetary bodies by measuring flows from orbital images of Venus, Mars, and the moon. All are fractal and have D consistent with the range of terrestrial a'a and have D consistent with the range of terrestrial a'a and pahoehoe values.

  13. Hypoxic stop-flow liver perfusion: Preliminary results in the treatment of multiple hepatic metastases; Perfusione antiblastica ipossica con blocco del flusso nella terapia delle metastasi epatiche: Risultati preliminari

    Energy Technology Data Exchange (ETDEWEB)

    Roversi, Rigoantonio; Ricci, Stefano; Rossi, Giuseppe; Roversi, Marina [Ospedale ``Bellaria - C.A. Pizzardi``, Bologna (Italy). Servizio di Radiologia Diagnostica; Cavallo, Giovanna [Ospedale ``Bellaria - C.A. Pizzardi``, Bologna (Italy). Divisione di Radioterapia e Oncologia; Fiorentini, Gianmaria [Ospedale ``S. Maria delle Croci``, Ravenna (Italy). Divisione di Oncologia


    Patients and methods: 27 patients (14 men and 13 women aged 35 to 71 years; average: 59 years), with 3-11 months` follow-up (average: 5 months) were treated for hepatic metastases (17/22 from colorectal, 10/22 from other primary tumors) with hypoxic locoregional hepatic perfusion. Sixteen of 22 patients had been pretreated with resection, systemic chemotherapy or free flow locoregional infusion. Their protocol consists in blocking arterial flow with an occlusion balloon catheter inflated in the hepatic artery; the main catheter channel is connected with a pump system and 250-300 ml saline with 30-40 mg Mitomycin C are perfused in the arterial hepatic system. Results: 19/27 patients are still alive, and 8/27 are dead but death was caused by the progression of intrahepatic disease in only 2/27 (7 %). Iatrogenic lesions of the arterial wall were shown at follow-up DSA in 15/22 patients (56 %). Thirteen CR (48 %) and 9 PR (33 %) were demonstrated at CT follow-up amounting to 81 % of objective responses. Follow-up showed a clinical CR in 12/18 symptomatic patients (66 %). No case of hematologic toxicity was observed. Mean CEA values changed from 129 to 10.60. Twelve of 27 patients exhibited mild posttreatment sequels, none of them lasting longer than three days; ischemic cholecystitis was seen in 3/15 cases (14 %). Conclusions: The occlusion catheters on the market are not optimal for this procedure; the axillary percutaneous approach is advantageous. CR rate was very high in their series but the objective response rate doses do not differ from those in the series with free-flow procedures. The highest CR rate was observed in untreated patients; the rate of clinical sequels was low, clinical CR rates were high and there was non hematologic toxicity. This well-tolerated procedure provides good local disease control, but the high rate of deaths from extrahepatic progression suggests that systemic chemotherapy and long-step intraarterial perfusion be combined.

  14. Predicting Peak Flows following Forest Fires (United States)

    Elliot, William J.; Miller, Mary Ellen; Dobre, Mariana


    Following forest fires, peak flows in perennial and ephemeral streams often increase by a factor of 10 or more. This increase in peak flow rate may overwhelm existing downstream structures, such as road culverts, causing serious damage to road fills at stream crossings. In order to predict peak flow rates following wildfires, we have applied two different tools. One is based on the U.S.D.A Natural Resource Conservation Service Curve Number Method (CN), and the other is by applying the Water Erosion Prediction Project (WEPP) to the watershed. In our presentation, we will describe the science behind the two methods, and present the main variables for each model. We will then provide an example of a comparison of the two methods to a fire-prone watershed upstream of the City of Flagstaff, Arizona, USA, where a fire spread model was applied for current fuel loads, and for likely fuel loads following a fuel reduction treatment. When applying the curve number method, determining the time to peak flow can be problematic for low severity fires because the runoff flow paths are both surface and through shallow lateral flow. The WEPP watershed version incorporates shallow lateral flow into stream channels. However, the version of the WEPP model that was used for this study did not have channel routing capabilities, but rather relied on regression relationships to estimate peak flows from individual hillslope polygon peak runoff rates. We found that the two methods gave similar results if applied correctly, with the WEPP predictions somewhat greater than the CN predictions. Later releases of the WEPP model have incorporated alternative methods for routing peak flows that need to be evaluated.

  15. Flow in rod bundles

    International Nuclear Information System (INIS)

    Hazi, G.; Mayer, G.


    For power upgrading VVER-440 reactors we need to know exactly how the temperature measured by the thermocouples is related to the average outlet temperature of the fuel assemblies. Accordingly, detailed knowledge on mixing process in the rod bundles and in the fuel assembly head have great importance. Here we study the hydrodynamics of rod bundles based on the results of direct numerical and large eddy simulation of flows in subchannels. It is shown that secondary flow and flow pulsation phenomena can be observed using both methodologies. Some consequences of these observations are briefly discussed. (author)

  16. Initiation of slug flow

    International Nuclear Information System (INIS)

    Hanratty, T.J.; Woods, B.D.


    The initiation of slug flow in a horizontal pipe can be predicted either by considering the stability of a slug or by considering the stability of a stratified flow. Measurements of the shedding rate of slugs are used to define necessary conditions for the existence of a slug. Recent results show that slugs develop from an unstable stratified flow through the evolution of small wavelength waves into large wavelength waves that have the possibility of growing to form a slug. The mechanism appears to be quite different for fluids with viscosities close to water than for fluids with large viscosities (20 centipoise)

  17. Magnetic vortex filament flows

    International Nuclear Information System (INIS)

    Barros, Manuel; Cabrerizo, Jose L.; Fernandez, Manuel; Romero, Alfonso


    We exhibit a variational approach to study the magnetic flow associated with a Killing magnetic field in dimension 3. In this context, the solutions of the Lorentz force equation are viewed as Kirchhoff elastic rods and conversely. This provides an amazing connection between two apparently unrelated physical models and, in particular, it ties the classical elastic theory with the Hall effect. Then, these magnetic flows can be regarded as vortex filament flows within the localized induction approximation. The Hasimoto transformation can be used to see the magnetic trajectories as solutions of the cubic nonlinear Schroedinger equation showing the solitonic nature of those

  18. Cash flow statement

    Directory of Open Access Journals (Sweden)

    Pavlović Miloš


    Full Text Available A cash flow is "bloodstream" of business and without constant cash flow a company would not be able to function. The cash flow statement is statutory financial report that provides information to the interested parties on cash inflows and outflows from operating, investing and financing activities during the accounting period. This paper will discuss the origin and significance of the cash slow statement; in addition, we will define the main categories of this statement and present the methodology of its composition in accordance with IAS 7.

  19. Red Cedar River Basin, Wisconsin; low-flow characteristics (United States)

    Gebert, W.A.


    Low-flow characteristics in the Red Cedar River basin, Wis., where surplus water may be diverted, and methods to determine low-flow characteristics at additional sites are presented. The low-flow characteristics were determined by various methods at 71 sites. For the three gaging stations in the basin, frequency analysis was used to determine the low-flow characteristics. At 17 partial-record sites correlation analyses were used to estimate the low-flow characteristics. Where only a single base-flow measurement was available (41 sites), equations were developed to estimate low-flow characteristics. The relationships were determined from multiple-regression analyses that related low-flow characteristics at gaging stations, low-flow partial-record stations, and sewage-treatment-plant sites to the drainage area and base-flow index values. The standard errors of estimate were determined to be 25 percent for the Q7,2 equation and 34 percent for the Q7,10 equation. For the main stem of the Red Cedar River where only one discharge measurement was available the low-flow characteristics were determined from a drainage area-discharge relationship. Low-flow characteristics were determined at an additional 30 sites in the Red Cedar River basin by various methods. The method used for these sites depended upon the type and amount of data available at each site. (Woodard-USGS)

  20. Refrigeration. Two-Phase Flow. Flow Regimes and Pressure Drop

    DEFF Research Database (Denmark)

    Knudsen, Hans-Jørgen Høgaard


    The note gives the basic definitions used in two-phase flow. Flow regimes and flow regimes map are introduced. The different contributions to the pressure drop are stated together with an imperical correlation from the litterature.......The note gives the basic definitions used in two-phase flow. Flow regimes and flow regimes map are introduced. The different contributions to the pressure drop are stated together with an imperical correlation from the litterature....

  1. Improving flow distribution in influent channels using computational fluid dynamics. (United States)

    Park, No-Suk; Yoon, Sukmin; Jeong, Woochang; Lee, Seungjae


    Although the flow distribution in an influent channel where the inflow is split into each treatment process in a wastewater treatment plant greatly affects the efficiency of the process, and a weir is the typical structure for the flow distribution, to the authors' knowledge, there is a paucity of research on the flow distribution in an open channel with a weir. In this study, the influent channel of a real-scale wastewater treatment plant was used, installing a suppressed rectangular weir that has a horizontal crest to cross the full channel width. The flow distribution in the influent channel was analyzed using a validated computational fluid dynamics model to investigate (1) the comparison of single-phase and two-phase simulation, (2) the improved procedure of the prototype channel, and (3) the effect of the inflow rate on flow distribution. The results show that two-phase simulation is more reliable due to the description of the free-surface fluctuations. It should first be considered for improving flow distribution to prevent a short-circuit flow, and the difference in the kinetic energy with the inflow rate makes flow distribution trends different. The authors believe that this case study is helpful for improving flow distribution in an influent channel.

  2. Glial and neuronal control of brain blood flow

    DEFF Research Database (Denmark)

    Attwell, David; Buchan, Alastair M; Charpak, Serge


    Blood flow in the brain is regulated by neurons and astrocytes. Knowledge of how these cells control blood flow is crucial for understanding how neural computation is powered, for interpreting functional imaging scans of brains, and for developing treatments for neurological disorders. It is now...

  3. Complex Flow Workshop Report

    Energy Technology Data Exchange (ETDEWEB)



    This report documents findings from a workshop on the impacts of complex wind flows in and out of wind turbine environments, the research needs, and the challenges of meteorological and engineering modeling at regional, wind plant, and wind turbine scales.

  4. Reversed extension flow

    DEFF Research Database (Denmark)

    Nielsen, Jens Kromann; Rasmussen, Henrik K.


    Afilament stretching rheometer (FSR) was used for measuring the start-up of uni-axial elongational flow followed by reversed bi-axial flow, both with a constant elongational rate. A narrow molecular mass distribution linear polystyrene with a molecular weight of 145 kg / mole wis subjected...... to the start-up of elongation for three Hencky strain units and subsequently the reversed flow. The integral molecular stress function formulation within the 'interchain pressure' concept agrees with the experiments. In the experiments the Hencky strain at which the str~ss becomes zero (the recovery strain......) in the reversed flow has been identified. The recovery strain is found to increase with elongational rate, and has a maximum value of approximately 1.45. The Doi Edwards model using any stretch evolution equation is not able to predict the correct level of the recovery strain....

  5. Web life: Ice Flows (United States)


    Computer and video gamers of a certain vintage will have fond memories of Lemmings, a game in which players must shepherd pixelated, suicidal rodents around a series of obstacles to reach safety. At first glance, Ice Flows is strikingly similar.

  6. Turbulent flow computation

    National Research Council Canada - National Science Library

    Drikakis, D; Geurts, Bernard


    ... discretization 3 A test-case: turbulent channel flow 4 Conclusions 75 75 82 93 98 4 Analysis and control of errors in the numerical simulation of turbulence Sandip Ghosal 1 Introduction 2 Source...

  7. Flow Cytometry Section (United States)

    Federal Laboratory Consortium — The primary goal of the Flow Cytometry Section is to provide the services of state-of-the-art multi-parameter cellular analysis and cell sorting for researchers and...

  8. Flow cytometry bioinformatics.

    Directory of Open Access Journals (Sweden)

    Kieran O'Neill

    Full Text Available Flow cytometry bioinformatics is the application of bioinformatics to flow cytometry data, which involves storing, retrieving, organizing, and analyzing flow cytometry data using extensive computational resources and tools. Flow cytometry bioinformatics requires extensive use of and contributes to the development of techniques from computational statistics and machine learning. Flow cytometry and related methods allow the quantification of multiple independent biomarkers on large numbers of single cells. The rapid growth in the multidimensionality and throughput of flow cytometry data, particularly in the 2000s, has led to the creation of a variety of computational analysis methods, data standards, and public databases for the sharing of results. Computational methods exist to assist in the preprocessing of flow cytometry data, identifying cell populations within it, matching those cell populations across samples, and performing diagnosis and discovery using the results of previous steps. For preprocessing, this includes compensating for spectral overlap, transforming data onto scales conducive to visualization and analysis, assessing data for quality, and normalizing data across samples and experiments. For population identification, tools are available to aid traditional manual identification of populations in two-dimensional scatter plots (gating, to use dimensionality reduction to aid gating, and to find populations automatically in higher dimensional space in a variety of ways. It is also possible to characterize data in more comprehensive ways, such as the density-guided binary space partitioning technique known as probability binning, or by combinatorial gating. Finally, diagnosis using flow cytometry data can be aided by supervised learning techniques, and discovery of new cell types of biological importance by high-throughput statistical methods, as part of pipelines incorporating all of the aforementioned methods. Open standards, data

  9. RCA and information flow

    International Nuclear Information System (INIS)


    RCA is an inter-governmental agreement among IAEA Member States in Asia and the Pacific. The Member States are Australia, Bangladesh, China, India, Indonesia, Japan, Korea, Malaysia, Mongolia, Myanmar, New Zealand, Pakistan, The Philippines, Singapore, Sri Lanka, Thailand and Viet Nam. The RCA Thematic Sectors are Agriculture, Human Health, Industry, Environment, Energy, Research Reactors, Radiation Safety, Electronic Networking and Outreach. This PowerPoint presentation gives an overview about the RCA projects, the information flow mechanism and the information flow programme

  10. Flow assurance study


    Böser, W.; Belfroid, S.P.C.


    Generally large scale carbon capture projects require pipeline systems for the transporting of the CO2 from its point of capture to the storage site. The article will give information on the proposed operational management system. This has to work for all process situations, ranging from steady flow at varying injection conditions and flow rates, to start-up and shutdown procedures and also for emergency shutdown at the platform. In all these operational situations the phase behaviour of CO2 ...

  11. Electrochemical flow capacitors (United States)

    Gogotsi, Yury; Presser, Volker; Kumbur, Emin Caglan


    The present invention generally relates to devices for energy storage technologies, and more particularly to electrochemical flow capacitor systems and applications. In some aspects, these flow capacitors have at least one electrode comprising a non-stationary solid or semi-solid composition comprising supercapacitive particles and an electrolytic solvent in electrical communication with at least one current collector, and energy is stored and/or released by charging and/or discharging the electrode(s).

  12. Flow energy conversion system

    International Nuclear Information System (INIS)

    Sargsyan, R.A.


    A cost-effective hydropower system called here Flow Energy Converter was developed, patented, manufactured and tested for water pumping, electricity generation and other purposes especially useful for the rural communities. The system consists of water-driven turbine with plane-surface blades, power transmission means and pump and/or generator. Working sample of the Flow Energy Converter was designed and manufactured at the Institute of Radio Physics and Electronics

  13. Stability of parallel flows

    CERN Document Server

    Betchov, R


    Stability of Parallel Flows provides information pertinent to hydrodynamical stability. This book explores the stability problems that occur in various fields, including electronics, mechanics, oceanography, administration, economics, as well as naval and aeronautical engineering. Organized into two parts encompassing 10 chapters, this book starts with an overview of the general equations of a two-dimensional incompressible flow. This text then explores the stability of a laminar boundary layer and presents the equation of the inviscid approximation. Other chapters present the general equation

  14. Flow with Negative Differential Viscosity


    川口, 明彦; Akihiko, KAWAGUCHI; 京大人環; Graduate School of Human and Enviromental Studies, Kyoto University


    Only a monotonous flow appears to the movement of the incompressible flow body in a porous medium under a simple condition according to Darcy's law. However, the character of the flow changes greatly if we think about the model by which the temperature dependency in the coefficient of viscosity is considered. Becoming of the inclination of pressure deifference-flow velocity specific characteristics nagative if we think about the one-dimensnional flow under a suitable condition, that is, "Flow...

  15. Modular load flow for restructured power systems

    CERN Document Server

    Hariharan, M V; Gupta, Pragati P


    In the subject of power systems, authors felt that a re-look is necessary at some conventional methods of analysis. In this book, the authors have subjected the time-honoured load flow to a close scrutiny. Authors have discovered and discussed a new load flow procedure – Modular Load Flow. Modular Load Flow explores use of power – a scalar – as source for electrical circuits which are conventionally analysed by means of phasors – the ac voltages or currents. The method embeds Kirchhoff’s circuit laws as topological property into its scalar equations and results in a unique wonderland where phase angles do not exist! Generators are shown to have their own worlds which can be superimposed to obtain the state of the composite power system. The treatment is useful in restructured power systems where stakeholders and the system operators may desire to know individual generator contributions in line flows and line losses for commercial reasons. Solution in Modular Load Flow consists of explicit expression...

  16. Pulsatile flow in ventricular catheters for hydrocephalus (United States)

    Giménez, Á.; Galarza, M.; Thomale, U.; Schuhmann, M. U.; Valero, J.; Amigó, J. M.


    The obstruction of ventricular catheters (VCs) is a major problem in the standard treatment of hydrocephalus, the flow pattern of the cerebrospinal fluid (CSF) being one important factor thereof. As a first approach to this problem, some of the authors studied previously the CSF flow through VCs under time-independent boundary conditions by means of computational fluid dynamics in three-dimensional models. This allowed us to derive a few basic principles which led to designs with improved flow patterns regarding the obstruction problem. However, the flow of the CSF has actually a pulsatile nature because of the heart beating and blood flow. To address this fact, here we extend our previous computational study to models with oscillatory boundary conditions. The new results will be compared with the results for constant flows and discussed. It turns out that the corrections due to the pulsatility of the CSF are quantitatively small, which reinforces our previous findings and conclusions. This article is part of the themed issue `Mathematical methods in medicine: neuroscience, cardiology and pathology'.

  17. Laminar flow resistance in short microtubes

    Energy Technology Data Exchange (ETDEWEB)

    Phares, D.J. [Texas A and M University, College Station, TX (United States). Dept. of Mechanical Engineering; Smedley, G.T.; Zhou, J. [Glaukos Corp., Laguna Hills, CA (United States). Dept. of Research and Development


    We have measured the pressure drop for the flow of liquid through a series of short microtubes ranging from 80 to 150 {mu}m in diameter with aspect ratios between L/D = 2 and L/D = 5. These dimensions were selected to resemble lumens of implantable microstents that are under consideration for the treatment of glaucoma. For physiologically relevant pressure drops and flow rates, we have determined that a fully-developed laminar pipe flow may be assumed throughout the microtube when (L/D) > 0.20Re, where Re is the Reynolds number based on the diameter, D, and L is the length of the tube. We have examined flow rates between 0.1 and 10 {mu}L/s, corresponding to Reynolds numbers between 1 and 150. For smooth microtubes, no difference from macroscopic flow is observed for the tube sizes considered. However, flow resistance is found to be sensitive to the relative surface roughness of the tube walls. (author)

  18. Xerostomia: causes and treatment. (United States)

    Wick, Jeanette Y


    When reduced salivary flow causes perpetual dry and sticky mucosa or sticky, stringy saliva, it becomes xerostomia-not a disease, but a symptom. Up to 30% of various populations self-report dry mouth (xerostomia) or have proven low salivary flow rates. Saliva is necessary for digestion and dental health, and it may have yet-unidentified immunological roles in humans. Xerostomia can lead to digestive problems, weight loss, and accelerated dental decay. Medications-several hundred of them-can cause or exacerbate xerostomia. Cancer, autoimmune diseases, and bone marrow transplants are associated with xerostomia. Including a dentist on the treatment team is essential for residents with dry mouth. As xerostomia progresses, they should shift focus primarily to prevention, maintenance, oral comfort, and emergency treatment. In all stages, they should keep treatment noninvasive if possible.

  19. Wastewater treatment

    Directory of Open Access Journals (Sweden)

    Ranđel N. Kitanović


    mechanical, chemical and biological agents. Mechanical methods are based on the effect of physical forces. Chemical agents are based on chemical processes. Biological measures are based on natural laws and activities of living beings. Water saving and its rational use are some of the most effective ways of saving water from pollution. Water treatment Water treatment is done in two ways: by sedimentation and filtration. Dirt falling on the bottom is called deposition. The passage of clean water through the material is called filtering. Water containing dissolved substances is purified by distillation. To improve the taste of distilled water, aeration should be performed. The sun’s ultraviolet rays destroy biological pollutants. Mechanical, biological and chemical methods are used for water purification. Mechanical methods Mechanical methods are based on the removal of physical impurities from water and the action of natural forces. For this purpose we use: grids and sieves, sedimentation, flotation, filtration, centrifugation, sand sedimentation tanks, grease traps, primary sedimentation tanks and flow equalization tanks. Wastewater aeration equipment is also used within these facilities. Grids and Sieves Larger, insoluble and floating substances in wastewater are removed with grids and sieves. Sedimentation The application of grids and sieves as well as sand sedimentation tanks and grease traps can be viewed as a process of deposition using certain infrastructure facilities intended for this type of separation of impurities. Infrastructure facilities are sedimentation tanks. There are vertical, horizontal and radial flow sedimentation tanks. Flotation Particle resurfacing with bubbles of air is called flotation. The best effect is achieved by aeration of bubbles of smaller diameters in a larger area. Filtration Filtration is a process used in water conditioning to remove insoluble substances. During filtration, water passes through a layer of granular material placed on a

  20. Assessment of a combined dry anaerobic digestion and post-composting treatment facility for source-separated organic household waste, using material and substance flow analysis and life cycle inventory. (United States)

    Jensen, Morten Bang; Møller, Jacob; Scheutz, Charlotte


    The fate of total solids, volatile solids, total organic carbon, fossil carbon, biogenic carbon and 17 substances (As, Ca, CaCO 3 , Cd, Cl, Cr, Cu, H, Hg, K, Mg, N, Ni, O, P, Pb, S, Zn) in a combined dry anaerobic digestion and post-composting facility were assessed. Mass balances showed good results with low uncertainties for non-volatile substances, while balances for nitrogen, carbon, volatile solids and total organic carbon showed larger but reasonable uncertainties, due to volatilisation and emissions into the air. Material and substance flow analyses were performed in order to obtain transfer coefficients for a combined dry anaerobic digestion and post-composting facility. All metals passed through the facility and ended up in compost or residues, but all concentrations of metals in the compost complied with legislation. About 23% of the carbon content of the organic waste was transferred to the biogas, 24% to the compost, 13% to residues and 40% into the atmosphere. For nitrogen, 69% was transferred to the compost, 10% volatilised to the biofilter, 11% directly into the atmosphere and 10% to residues. Finally, a full life cycle inventory was conducted for the combined dry anaerobic digestion and post-composting facility, including waste received, fuel consumption, energy use, gaseous emissions, products, energy production and chemical composition of the compost produced. Copyright © 2017. Published by Elsevier Ltd.

  1. Planetary heat flow measurements. (United States)

    Hagermann, Axel


    The year 2005 marks the 35th anniversary of the Apollo 13 mission, probably the most successful failure in the history of manned spaceflight. Naturally, Apollo 13's scientific payload is far less known than the spectacular accident and subsequent rescue of its crew. Among other instruments, it carried the first instrument designed to measure the flux of heat on a planetary body other than Earth. The year 2005 also should have marked the launch of the Japanese LUNAR-A mission, and ESA's Rosetta mission is slowly approaching comet Churyumov-Gerasimenko. Both missions carry penetrators to study the heat flow from their target bodies. What is so interesting about planetary heat flow? What can we learn from it and how do we measure it?Not only the Sun, but all planets in the Solar System are essentially heat engines. Various heat sources or heat reservoirs drive intrinsic and surface processes, causing 'dead balls of rock, ice or gas' to evolve dynamically over time, driving convection that powers tectonic processes and spawns magnetic fields. The heat flow constrains models of the thermal evolution of a planet and also its composition because it provides an upper limit for the bulk abundance of radioactive elements. On Earth, the global variation of heat flow also reflects the tectonic activity: heat flow increases towards the young ocean ridges, whereas it is rather low on the old continental shields. It is not surprising that surface heat flow measurements, or even estimates, where performed, contributed greatly to our understanding of what happens inside the planets. In this article, I will review the results and the methods used in past heat flow measurements and speculate on the targets and design of future experiments.

  2. Oscillatory flow chemical reactors

    Directory of Open Access Journals (Sweden)

    Slavnić Danijela S.


    Full Text Available Global market competition, increase in energy and other production costs, demands for high quality products and reduction of waste are forcing pharmaceutical, fine chemicals and biochemical industries, to search for radical solutions. One of the most effective ways to improve the overall production (cost reduction and better control of reactions is a transition from batch to continuous processes. However, the reactions of interests for the mentioned industry sectors are often slow, thus continuous tubular reactors would be impractically long for flow regimes which provide sufficient heat and mass transfer and narrow residence time distribution. The oscillatory flow reactors (OFR are newer type of tube reactors which can offer solution by providing continuous operation with approximately plug flow pattern, low shear stress rates and enhanced mass and heat transfer. These benefits are the result of very good mixing in OFR achieved by vortex generation. OFR consists of cylindrical tube containing equally spaced orifice baffles. Fluid oscillations are superimposed on a net (laminar flow. Eddies are generated when oscillating fluid collides with baffles and passes through orifices. Generation and propagation of vortices create uniform mixing in each reactor cavity (between baffles, providing an overall flow pattern which is close to plug flow. Oscillations can be created by direct action of a piston or a diaphragm on fluid (or alternatively on baffles. This article provides an overview of oscillatory flow reactor technology, its operating principles and basic design and scale - up characteristics. Further, the article reviews the key research findings in heat and mass transfer, shear stress, residence time distribution in OFR, presenting their advantages over the conventional reactors. Finally, relevant process intensification examples from pharmaceutical, polymer and biofuels industries are presented.

  3. Blood flow patterns underlie developmental heart defects. (United States)

    Midgett, Madeline; Thornburg, Kent; Rugonyi, Sandra


    Although cardiac malformations at birth are typically associated with genetic anomalies, blood flow dynamics also play a crucial role in heart formation. However, the relationship between blood flow patterns in the early embryo and later cardiovascular malformation has not been determined. We used the chicken embryo model to quantify the extent to which anomalous blood flow patterns predict cardiac defects that resemble those in humans and found that restricting either the inflow to the heart or the outflow led to reproducible abnormalities with a dose-response type relationship between blood flow stimuli and the expression of cardiac phenotypes. Constricting the outflow tract by 10-35% led predominantly to ventricular septal defects, whereas constricting by 35-60% most often led to double outlet right ventricle. Ligation of the vitelline vein caused mostly pharyngeal arch artery malformations. We show that both cardiac inflow reduction and graded outflow constriction strongly influence the development of specific and persistent abnormal cardiac structure and function. Moreover, the hemodynamic-associated cardiac defects recapitulate those caused by genetic disorders. Thus our data demonstrate the importance of investigating embryonic blood flow conditions to understand the root causes of congenital heart disease as a prerequisite to future prevention and treatment. NEW & NOTEWORTHY Congenital heart defects result from genetic anomalies, teratogen exposure, and altered blood flow during embryonic development. We show here a novel "dose-response" type relationship between the level of blood flow alteration and manifestation of specific cardiac phenotypes. We speculate that abnormal blood flow may frequently underlie congenital heart defects. Copyright © 2017 the American Physiological Society.

  4. Flow: Statistics, visualization and informatics for flow cytometry

    Directory of Open Access Journals (Sweden)

    Kepler Thomas B


    Full Text Available Abstract Flow is an open source software application for clinical and experimental researchers to perform exploratory data analysis, clustering and annotation of flow cytometric data. Flow is an extensible system that offers the ease of use commonly found in commercial flow cytometry software packages and the statistical power of academic packages like the R BioConductor project.

  5. Load flow analysis using decoupled fuzzy load flow under critical ...

    African Journals Online (AJOL)


    The conventional load flow methods like Newton-Raphson load flow (NRLF), Fast Decoupled load flow (FDLF) provide poor performance under critical conditions such as high R/X ratio, heavily loading condition etc. Exploiting the decoupling properties of power system, reliable fuzzy load flow is developed to overcome the ...

  6. Tomographic multiphase flow measurement

    International Nuclear Information System (INIS)

    Sætre, C.; Johansen, G.A.; Tjugum, S.A.


    Measurement of multiphase flow of gas, oil and water is not at all trivial and in spite of considerable achievements over the past two decades, important challenges remain (). These are related to reducing measurement uncertainties arising from variations in the flow regime, improving long term stability and developing new means for calibration, adjustment and verification of the multiphase flow meters. This work focuses on the first two issues using multi gamma beam (MGB) measurements for identification of the type of flow regime. Further gamma ray tomographic measurements are used for reference of the gas/liquid distribution. For the MGB method one Am-241 source with principal emission at 59.5 keV is used because this relatively low energy enables efficient collimation and thereby shaping of the beams, as well as compact detectors. One detector is placed diametrically opposite the source whereas the second is positioned to the side so that this beam is close to the pipe wall. The principle is then straight forward to compare the measured intensities of these detectors and through that identify the flow pattern, i.e. the instantaneous cross-sectional gas-liquid distribution. The measurement setup also includes Compton scattering measurements, which can provide information about the changes in the water salinity for flow segments with high water liquid ratio and low gas fractions. By measuring the transmitted intensity in short time slots (<100ms), rapid regime variations are revealed. From this we can select the time sections suitable for salinity measurements. Since the salinity variations change at the time scale of hours, a running average can be performed to increase the accuracy of the measurements. Recent results of this work will be presented here. - Highlights: ► Multiphase flow gas-fraction and flow regime measurements by multi gamma ray beams. ► High-speed gamma ray tomograph as reference for the flow pattern and gas fraction. ► Dual modality

  7. Radiotracer techniques for measuring fluid flow and calibrating flow meters

    International Nuclear Information System (INIS)

    Cooper, E.L.


    Radiotracer techniques can be used to measure accurately both gas and liquid flow rates under operating conditions in a wide range of flow systems. They are ideally suited for calibrating flow meters as well as for measuring unmetered flows in industrial plants. Applications of these techniques range from measuring the flows of fuels and process fluids for energy and mass balance studies to measuring the flows of liquid and airborne effluents for pollution control. This report describes the various radiotracer techniques which can be used to measure fluid flows. The range of application and inherent accuracy of each technique is discussed

  8. Upscaling of Forchheimer flows

    KAUST Repository

    Aulisa, Eugenio


    In this work we propose upscaling method for nonlinear Forchheimer flow in heterogeneous porous media. The generalized Forchheimer law is considered for incompressible and slightly-compressible single-phase flows. We use recently developed analytical results (Aulisa et al., 2009) [1] and formulate the resulting system in terms of a degenerate nonlinear flow equation for the pressure with the nonlinearity depending on the pressure gradient. The coarse scale parameters for the steady state problem are determined so that the volumetric average of velocity of the flow in the domain on fine scale and on coarse scale are close. A flow-based coarsening approach is used, where the equivalent permeability tensor is first evaluated following streamline methods for linear cases, and modified in order to take into account the nonlinear effects. Compared to previous works (Garibotti and Peszynska, 2009) [2], (Durlofsky and Karimi-Fard) [3], this approach can be combined with rigorous mathematical upscaling theory for monotone operators, (Efendiev et al., 2004) [4], using our recent theoretical results (Aulisa et al., 2009) [1]. The developed upscaling algorithm for nonlinear steady state problems is effectively used for variety of heterogeneities in the domain of computation. Direct numerical computations for average velocity and productivity index justify the usage of the coarse scale parameters obtained for the special steady state case in the fully transient problem. For nonlinear case analytical upscaling formulas in stratified domain are obtained. Numerical results were compared to these analytical formulas and proved to be highly accurate. © 2014.

  9. Micromodel foam flow study

    Energy Technology Data Exchange (ETDEWEB)

    Chambers, K.T.; Radke, C.J.


    Foams are often utilized as part of enhanced oil recovery techniques. This report presents the results of a micromodel foam flow study. Micromodels are valuable tools in uncovering capillary phenomena responsible for lamellae generation and coalescence during foam flow in porous media. Among the mechanisms observed are snap-off, weeping-flow breakup, and lamella division and leave behind. Coalescence mechanisms include dynamic capillary-pressure-induced lamella drainage and gas diffusion. These phenomena are sensitive to the mode of injection, the local capillary environment, and the geometry of the pore structure. An important consideration in presenting a tractable model of foam flow behavior is the ability to identify the pore-level mechanisms having the greatest impact on foam texture. The predominant mechanisms will vary depending upon the application for foam as an enhanced oil recovery (EOR) fluid. Both simultaneous gas and surfactant injection and surfactant alternating with gas injection (SAG) have been used to create foam for mobility control in EOR projects. The model developed is based on simultaneous gas and surfactant injection during steady-state conditions into a Berea sandstone core. The lamellae generation and coalescence mechanisms included in this model are snap-off, lamella division, and dynamic capillary-pressure-induced lamella drainage. This simplified steady-state model serves as a foundation for developing more complete rate expressions and for extending the population balance to handle transient foam flow behavior. 70 refs., 30 figs.

  10. Turbine flow meter response in two-phase flows

    International Nuclear Information System (INIS)

    Shim, W.J.; Dougherty, T.J.; Cheh, H.Y.


    The purpose of this paper is to suggest a simple method of calibrating turbine flow meters to measure the flow rates of each phase in a two-phase flow. The response of two 50.8 mm (2 inch) turbine flow meters to air-water, two-phase mixtures flowing vertically in a 57 mm I.D. (2.25 inch) polycarbonate tube has been investigated for both upflow and downflow. The flow meters were connected in series with an intervening valve to provide an adjustable pressure difference between them. Void fractions were measured by two gamma densitometers, one upstream of the flow meters and the other downstream. The output signal of the turbine flow meters was found to depend only on the actual volumetric flow rate of the gas, F G , and liquid, F L , at the location of the flow meter

  11. Designing reliability information flows

    International Nuclear Information System (INIS)

    Petkova, Valia T.; Lu Yuan; Ion, Roxana A.; Sander, Peter C.


    It is well-known [Reliab. Eng. Syst. Saf. 75 (2002) 295] that in modern development processes it is essential to have an information flow structure that facilitates fast feedback from product users (customers) to departments at the front end, in particular development and production. As information is only relevant if it is used when taking decisions, this paper presents a guideline for building field feedback information flows that facilitate the decision taking during the product creation and realisation process. The guideline takes into consideration that the type of decisions depends on the span-of-control, therefore following Parsons [Structure and Process in Modern Societies (1990)] the span-of-control is subdivided into the following three levels: strategic, tactic, and executive. The guideline is illustrated with a case in which it is used for analysing the quality of existing field feedback flows

  12. Particles in flows

    CERN Document Server

    Galdi, Giovanni; Nečasová, Šárka


    This book aims to face particles in flows from many different, but essentially interconnected sides and points of view. Thus the selection of authors and topics represented in the chapters, ranges from deep mathematical analysis of the associated models, through the techniques of their numerical solution, towards real applications and physical implications. The scope and structure of the book as well as the selection of authors was motivated by the very successful summer course and workshop "Particles in Flows'' that was held in Prague in the August of 2014. This meeting revealed the need for a book dealing with this specific and challenging multidisciplinary subject, i.e. particles in industrial, environmental and biomedical flows and the combination of fluid mechanics, solid body mechanics with various aspects of specific applications.

  13. Choked flow through cracks

    International Nuclear Information System (INIS)

    Feburie, V.; Giot, M.; Granger, S.; Seynhaeve, J.M.


    The leaks through steam-generator cracks are the subject of a research carried out in cooperation between EDF and UCL. A software called ECREVISSE to predict the mass flow rate has been developed and has been successfully validated. The purpose of the paper is to present the mathematical model used in ECREVISSE as well as some comparison between the results and the presently available data. The model takes into account the persistence of some metastable liquid in the crack and the special flow pattern which appears in such particular geometry. Although the model involves the use of several correlations (friction, heat transfer), no adjustment of parameters against the data has been needed, neither in the single-phase part of the flow, or in the two-phase part. (authors). 8 figs., 1 tab., 20 refs

  14. Robust Optical Flow Estimation

    Directory of Open Access Journals (Sweden)

    Javier Sánchez Pérez


    Full Text Available n this work, we describe an implementation of the variational method proposed by Brox etal. in 2004, which yields accurate optical flows with low running times. It has several benefitswith respect to the method of Horn and Schunck: it is more robust to the presence of outliers,produces piecewise-smooth flow fields and can cope with constant brightness changes. Thismethod relies on the brightness and gradient constancy assumptions, using the information ofthe image intensities and the image gradients to find correspondences. It also generalizes theuse of continuous L1 functionals, which help mitigate the effect of outliers and create a TotalVariation (TV regularization. Additionally, it introduces a simple temporal regularizationscheme that enforces a continuous temporal coherence of the flow fields.

  15. Numerical investigation of flow parameters for solid rigid spheroidal particle in a pulsatile pipe flow (United States)

    Varghese, Joffin; Jayakumar, J. S.


    Quantifying, forecasting and analysing the displacement rates of suspended particles are essential while discussing about blood flow analysis. Because blood is one of the major organs in the body, which enables transport phenomena, comprising of numerous blood cells. In order to model the blood flow, a flow domain was created and numerically simulated. Flow field velocity in the stream is solved utilizing Finite Volume Method utilizing FVM unstructured solver. In pulsatile flow, the effect of parameters such as average Reynolds number, tube radius, particle size and Womersley number are taken into account. In this study spheroidal particle trajectory in axial direction is simulated at different values of pulsating frequency including 1.2 Hz, 3.33 Hz and 4.00 Hz and various densities including 1005 kg/m3 and 1025 kg/m3 for the flow domain. The analysis accomplishes the interaction study of blood constituents for different flow situations which have applications in diagnosis and treatment of cardio vascular related diseases.

  16. Multiphase flow dynamics 5 nuclear thermal hydraulics

    CERN Document Server

    Kolev, Nikolay Ivanov


    This Volume 5 of the successful book package "Multiphase Flow Dynamics" is devoted to nuclear thermal hydraulics which is a substantial part of nuclear reactor safety. It provides knowledge and mathematical tools for adequate description of the process of transferring the fission heat released in materials due to nuclear reactions into its environment. It step by step introduces into the heat release inside the fuel, temperature fields in the fuels, the "simple" boiling flow in a pipe described using ideas of different complexity like equilibrium, non equilibrium, homogeneity, non homogeneity. Then the "simple" three-fluid boiling flow in a pipe is described by gradually involving the mechanisms like entrainment and deposition, dynamic fragmentation, collisions, coalescence, turbulence. All heat transfer mechanisms are introduced gradually discussing their uncertainty. Different techniques are introduced like boundary layer treatments or integral methods. Comparisons with experimental data at each step demons...

  17. Multiphase Flow Dynamics 5 Nuclear Thermal Hydraulics

    CERN Document Server

    Kolev, Nikolay Ivanov


    The present Volume 5 of the successful book package "Multiphase Flow Dynamics" is devoted to nuclear thermal hydraulics which is a substantial part of nuclear reactor safety. It provides knowledge and mathematical tools for adequate description of the process of transferring the fission heat released in materials due to nuclear reactions into its environment. It step by step introduces into the heat release inside the fuel, temperature fields in the fuels, the "simple" boiling flow in a pipe described using ideas of different complexity like equilibrium, non equilibrium, homogeneity, non homogeneity. Then the "simple" three-fluid boiling flow in a pipe is described by gradually involving the mechanisms like entrainment and deposition, dynamic fragmentation, collisions, coalescence, turbulence. All heat transfer mechanisms are introduced gradually discussing their uncertainty. Different techniques are introduced like boundary layer treatments or integral methods. Comparisons with experimental data at each step...

  18. Fluid Flow at Branching Junctions


    Sochi, Taha


    The flow of fluids at branching junctions plays important kinematic and dynamic roles in most biological and industrial flow systems. The present paper highlights some key issues related to the flow of fluids at these junctions with special emphasis on the biological flow networks particularly blood transportation vasculature.

  19. The squeezing flow

    Directory of Open Access Journals (Sweden)

    Nilankush Acharya


    Full Text Available The present article investigates the squeezing flow of two types of nanofluids such as Cu-water and Cu-kerosene between two parallel plates in the presence of magnetic field. The governing non-linear partial differential equations are transformed into ordinary differential equations by applying suitable similarity transformation and then solved numerically using RK-4 method with shooting technique and analytically using differential transformation method (DTM. The influence of arising relevant parameters on flow characteristics has been discussed through graphs and tables. A comparative study has been taken into account between existing results and present work and it is found to be in excellent harmony.

  20. Three-Dimensional Flows

    CERN Document Server

    Araujo, Vitor; Viana, Marcelo


    In this book, the authors present the elements of a general theory for flows on three-dimensional compact boundaryless manifolds, encompassing flows with equilibria accumulated by regular orbits. The book aims to provide a global perspective of this theory and make it easier for the reader to digest the growing literature on this subject. This is not the first book on the subject of dynamical systems, but there are distinct aspects which together make this book unique. Firstly, this book treats mostly continuous time dynamical systems, instead of its discrete counterpart, exhaustively treated

  1. Flow Analysis Software Toolkit (United States)

    Watson, Velvin; Castagnera, Karen; Plessel, Todd; Merritt, Fergus; Kelaita, Paul; West, John; Sandstrom, Tim; Clucas, Jean; Globus, AL; Bancroft, Gordon; hide


    Flow Analysis Software Toolkit (FAST) computer program provides software environment facilitating visualization of data. Collection of separate programs (modules) running simultaneously and helps user to examine results of numerical and experimental simulations. Intended for graphical depiction of computed flows, also assists in analysis of other types of data. Combines capabilities of such programs as PLOT3D, RIP, SURF, and GAS into one software environment with modules sharing data. All modules have consistent, highly interactive graphical user interface. Modular construction makes it flexible and extensible. Environment custom-configured, and new modules developed and added as needed. Written in ANSI compliant FORTRAN 77 and C language.

  2. Mechanics of fluid flow

    CERN Document Server

    Basniev, Kaplan S; Chilingar, George V 0


    The mechanics of fluid flow is a fundamental engineering discipline explaining both natural phenomena and human-induced processes, and a thorough understanding of it is central to the operations of the oil and gas industry.  This book, written by some of the world's best-known and respected petroleum engineers, covers the concepts, theories, and applications of the mechanics of fluid flow for the veteran engineer working in the field and the student, alike.  It is a must-have for any engineer working in the oil and gas industry.

  3. Analysis of artery blood flow before and after angioplasty (United States)

    Tomaszewski, Michał; Baranowski, Paweł; Małachowski, Jerzy; Damaziak, Krzysztof; Bukała, Jakub


    The study presents a comparison of results obtained from numerical simulations of blood flow in two different arteries. One of them was considered to be narrowed in order to simulate an arteriosclerosis obstructing the blood flow in the vessel, whereas the second simulates the vessel after angioplasty treatment. During the treatment, a biodegradable stent is inserted into the artery, which prevents the vessel walls from collapsing. The treatment was simulated through the use of numerical simulation using the finite element method. The final mesh geometry obtained from the analysis was exported to the dedicated software in order to create geometry in which a flow domain inside the artery with the stent was created. The flow analysis was conducted in ANSYS Fluent software with non-deformable vessel walls.

  4. A new CFD modeling method for flow blockage accident investigations

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Wenyuan, E-mail:; Peng, Changhong, E-mail:; Chen, Yangli, E-mail:; Guo, Yun, E-mail:


    Highlights: • Porous-jump treatment is applied to CFD simulation on flow blockages. • Porous-jump treatment predicts consistent results with direct CFD treatment. • Relap5 predicts abnormal flow rate profiles in MTR SFA blockage scenario. • Relap5 fails to simulate annular heat flux in blockage case of annular assembly. • Porous-jump treatment provides reasonable and generalized CFD results. - Abstract: Inlet flow blockages in both flat and annular plate-type fuel assemblies are simulated by (Computational Fluid Dynamics) CFD and system analysis methods, with blockage ratio ranging from 60 to 90%. For all the blockage scenarios, mass flow rate of the blocked channel drops dramatically as blockage ratio increases, while mass flow rates of non-blocked channels are almost steady. As a result of over-simplifications, the system code fails to capture details of mass flow rate profiles of non-blocked channels and power redistribution of fuel plates. In order to acquire generalized CFD results, a new blockage modeling method is developed by using the porous-jump condition. For comparisons, direct CFD simulations are conducted toward postulated blockages. For the porous-jump treatment, conservative flow and heat transfer conditions are predicted for the blocked channel, while consistent predictions are obtained for non-blocked channels. Besides, flow fields in the blocked channel, asymmetric power redistributions of fuel plates, and complex heat transfer phenomena in annular fuel assembly are obtained and discussed. The present study indicates that the porous-jump condition is a reasonable blockage modeling method, which predicts generalized CFD results for flow blockages.

  5. Transient two-phase flow

    International Nuclear Information System (INIS)

    Hsu, Y.Y.


    The following papers related to two-phase flow are summarized: current assumptions made in two-phase flow modeling; two-phase unsteady blowdown from pipes, flow pattern in Laval nozzle and two-phase flow dynamics; dependence of radial heat and momentum diffusion; transient behavior of the liquid film around the expanding gas slug in a vertical tube; flooding phenomena in BWR fuel bundles; and transient effects in bubble two-phase flow. (U.S.)

  6. Using Crossflow for Flow Measurements and Flow Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Gurevich, A.; Chudnovsky, L.; Lopeza, A. [Advanced Measurement and Analysis Group Inc., Ontario (Canada); Park, M. H. [Sungjin Nuclear Engineering Co., Ltd., Gyeongju (Korea, Republic of)


    Ultrasonic Cross Correlation Flow Measurements are based on a flow measurement method that is based on measuring the transport time of turbulent structures. The cross correlation flow meter CROSSFLOW is designed and manufactured by Advanced Measurement and Analysis Group Inc. (AMAG), and is used around the world for various flow measurements. Particularly, CROSSFLOW has been used for boiler feedwater flow measurements, including Measurement Uncertainty Recovery (MUR) reactor power uprate in 14 nuclear reactors in the United States and in Europe. More than 100 CROSSFLOW transducers are currently installed in CANDU reactors around the world, including Wolsung NPP in Korea, for flow verification in ShutDown System (SDS) channels. Other CROSSFLOW applications include reactor coolant gross flow measurements, reactor channel flow measurements in all channels in CANDU reactors, boiler blowdown flow measurement, and service water flow measurement. Cross correlation flow measurement is a robust ultrasonic flow measurement tool used in nuclear power plants around the world for various applications. Mathematical modeling of the CROSSFLOW agrees well with laboratory test results and can be used as a tool in determining the effect of flow conditions on CROSSFLOW output and on designing and optimizing laboratory testing, in order to ensure traceability of field flow measurements to laboratory testing within desirable uncertainty.

  7. Is flow verification necessary

    International Nuclear Information System (INIS)

    Beetle, T.M.


    Safeguards test statistics are used in an attempt to detect diversion of special nuclear material. Under assumptions concerning possible manipulation (falsification) of safeguards accounting data, the effects on the statistics due to diversion and data manipulation are described algebraically. A comprehensive set of statistics that is capable of detecting any diversion of material is defined in terms of the algebraic properties of the effects. When the assumptions exclude collusion between persons in two material balance areas, then three sets of accounting statistics are shown to be comprehensive. Two of the sets contain widely known accountancy statistics. One of them does not require physical flow verification - comparisons of operator and inspector data for receipts and shipments. The third set contains a single statistic which does not require physical flow verification. In addition to not requiring technically difficult and expensive flow verification, this single statistic has several advantages over other comprehensive sets of statistics. This algebraic approach as an alternative to flow verification for safeguards accountancy is discussed in this paper

  8. Flow on noisy terrains

    DEFF Research Database (Denmark)

    Tsirogiannis, Konstantinos; Haverkort, Herman


    Computing watersheds on triangulated terrain models in a robust manner is a difficult task as it is sensitive to noise that appears in the elevation values of the input. This is amplified by the existence of many very small watersheds (corresponding to spurious minima) that obscure the overall hy...... to use a robust flow model together with exact arithmetic....

  9. Erosion in extruder flow (United States)

    Kaufman, Miron; Fodor, Petru S.

    A detailed analysis of the fluid flow in Tadmor's unwound channel model of the single screw extruder is performed by combining numerical and analytical methods. Using the analytical solution for the longitudinal velocity field (in the limit of zero Reynolds number) allows us to devote all the computational resources solely for a detailed numerical solution of the transversal velocity field. This high resolution 3D model of the fluid flow in a single-screw extruder allows us to identify the position and extent of Moffatt eddies that impede mixing. We further consider the erosion of particles (e.g. carbon-black agglomerates) advected by the polymeric flow. We assume a particle to be made of primary fragments bound together. In the erosion process a primary fragment breaks out of a given particle. Particles are advected by the laminar flow and they disperse because of the shear stresses imparted by the fluid. The time evolution of the numbers of particles of different sizes is described by the Bateman coupled differential equations used to model radioactivity. Using the particle size distribution we compute an entropic fragmentation index which varies from 0 for a monodisperse system to 1 for an extreme poly-disperse system.

  10. ECAL Energy Flow Calibration

    CERN Multimedia

    CERN. Geneva


    My talk will be covering my work as a whole over the course of the semester. The focus will be on using energy flow calibration in ECAL to check the precision of the corrections made by the light monitoring system used to account for transparency loss within ECAL crystals due to radiation damage over time.

  11. Flow Control and Diagnostics

    Indian Academy of Sciences (India)

    A multi-component wind tunnel balance, working with fibre-optic sensors, was already demonstrated by the authors in ... often for mapping surface pressure fields on wind tunnel models. The paint is a fluorescent ... When a gas turbine engine operates close to its peak performance, flow within the com- pressor can become ...

  12. Flow Injection Analysis

    DEFF Research Database (Denmark)

    Hansen, Elo Harald


    Learning objectives:* To provide an introduction to automated assays* To describe the basic principles of FIA * To demonstrate the capabilities of FIA in relation to batch assays and conventional continuous flow systems* To show that FIA allows one to augment existing analytical techniques* To show...

  13. Flow assurance study

    NARCIS (Netherlands)

    Böser, W.; Belfroid, S.P.C.


    Generally large scale carbon capture projects require pipeline systems for the transporting of the CO2 from its point of capture to the storage site. The article will give information on the proposed operational management system. This has to work for all process situations, ranging from steady flow

  14. Quaternions and ideal flows

    Energy Technology Data Exchange (ETDEWEB)

    Eshraghi, H [Iran University of Science and Technology (IUST), School of Physics, Institute for Studies in Theoretical Physics and Mathematics, Tehran (Iran, Islamic Republic of); Gibbon, J D [Department of Mathematics, Imperial College London, London SW7 2AZ (United Kingdom)


    After a review of some of the recent works by Holm and Gibbon on quaternions and their application to Lagrangian flows, particularly the incompressible Euler equations and the equations of ideal MHD, this paper investigates the compressible and relativistic Euler equations using these methods.

  15. Water Flow Experiments

    Indian Academy of Sciences (India)

    This is a simple exercise in elementary fluid dynamics for the undergraduate and the secondary school level. Here, we explore the flow of water through an orifice at the bottom of a cylindri- cal bottle/tank, first through a tube attached to the bottom of the bottle/tank and then without the tube. The experiment is easy to perform.

  16. Lateral flow assays

    NARCIS (Netherlands)

    Posthuma-Trumpie, G.A.; Amerongen, van A.


    A simple version of immunochemical-based methods is the Lateral Flow Assay (LFA). It is a dry chemistry technique (reagents are included); the fluid from the sample runs through a porous membrane (often nitrocellulose) by capillary force. Typically the membrane is cut as a strip of 0.5*5 cm. In most

  17. Probabilistic Load Flow

    DEFF Research Database (Denmark)

    Chen, Peiyuan; Chen, Zhe; Bak-Jensen, Birgitte


    This paper reviews the development of the probabilistic load flow (PLF) techniques. Applications of the PLF techniques in different areas of power system steady-state analysis are also discussed. The purpose of the review is to identify different available PLF techniques and their corresponding...

  18. CFD simulation of neutral ABL flows

    DEFF Research Database (Denmark)

    Zhang, Xiaodong

    This work is to evaluate the CFD prediction of Atmospheric Boundary Layer flow field over different terrains employing Fluent 6.3 software. How accurate the simulation could achieve depend on following aspects: viscous model, wall functions, agreement of CFD model with inlet wind velocity profile...... and top boundary condition. Fluent employ wall function roughness modifications based on data from experiments with sand grain roughened pipes and channels, describe wall adjacent zone with Roughness Height (Ks) instead of Roughness Length (z0). In a CFD simulation of ABL flow, the mean wind velocity...... could do. In this paper, a new near wall treatment function is designed, which, in some degree, can correct the horizontal gradients problem. Based on the corrected model constants and near wall treatment function, a simulation of Askervein Hill is carried out. The wind condition is neutrally stratified...

  19. Enceladus' Enigmatic Heat Flow (United States)

    Howett, C.; Spencer, J. R.; Spencer, D.; Verbiscer, A.; Hurford, T.; Segura, M.


    Accurate knowledge of Enceladus' heat flow is important because it provides a vital constraint on Enceladus' tidal dissipation mechanisms, orbital evolution, and the physical processes that generate the plumes. In 2011 we published an estimate of the current heat flow from Enceladus' active south polar terrain: 15.8 +/- 3.1 GW (Howett et al., 2011). This value was calculated by first estimating by modeling, and then removing, the passive component from 17 to 1000 micron observations made of the entire south polar terrain by Cassini's Composite Infrared Spectrometer (CIRS). The heat flow was then directly calculated from the residual, assumed endogenic, component. The derived heat flow of 15.8 GW was surprisingly high, about 10 times greater than that predicted by steady-state tidal heating (Meyer and Wisdom, 2007). CIRS has also returned high spatial resolution observations of Enceladus' active south polar terrain. Two separate observations are used: 9 to 16 micron observations taken over nearly the complete south polar terrain and a single 17 to 1000 micron scan over Damascus, Baghdad and Cairo. The shorter wavelength observations are only sensitive to high temperature emission (>70 K), and so longer wavelength observations are required (despite their limited spatial coverage) to estimate the low temperature emission from the stripes. Analysis of these higher resolution observations tells a different story of Enceladus' endogenic heat flow: the preliminary estimate of the heat flow from the active tiger stripes using these observations is 4.2 GW. An additional 0.5 GW must be added to this number to account for the latent heat release by the plumes (Ingersoll and Pankine 2009), giving a total preliminary estimate of 4.9 GW. The discrepancy in these two numbers is significant and we are currently investigating the cause. One possible reason is that there is significantly higher endogenic emission from the regions between the tiger stripes than we currently estimate

  20. Simulation of turbulent flows containing strong shocks (United States)

    Fryxell, Bruce; Menon, Suresh


    Simulation of turbulent flows with strong shocks is a computationally challenging problem. The requirements for a method to produce accurate results for turbulence are orthogonal to those needed to treat shocks properly. In order to prevent an unphysical rate of decay of turbulent structures, it is necessary to use a method with very low numerical dissipation. Because of this, central difference schemes are widely used. However, computing strong shocks with a central difference scheme can produce unphysical post-shock oscillations that corrupt the entire flow unless additional dissipation is added. This dissipation can be difficult to localize to the area near the shock and can lead to inaccurate treatment of the turbulence. Modern high-resolution shock-capturing methods usually use upwind algorithms to provide the dissipation necessary to stabilize shocks. However, this upwind dissipation can also lead to an unphysical rate of decay of the turbulence. This paper discusses a hybrid method for simulating turbulent flows with strong shocks that couples a high-order central difference scheme with a high-resolution shock-capturing method. The shock-capturing method is used only in the vicinity of discontinuities in the flow, whereas the central difference scheme is used in the remainder of the computational domain. Results of this new method will be shown for a variety of test problems. Preliminary results for a realistic application involving detonation in gas-particle flows will also be presented.

  1. Simulation of turbulent flows containing strong shocks

    International Nuclear Information System (INIS)

    Fryxell, Bruce; Menon, Suresh


    Simulation of turbulent flows with strong shocks is a computationally challenging problem. The requirements for a method to produce accurate results for turbulence are orthogonal to those needed to treat shocks properly. In order to prevent an unphysical rate of decay of turbulent structures, it is necessary to use a method with very low numerical dissipation. Because of this, central difference schemes are widely used. However, computing strong shocks with a central difference scheme can produce unphysical post-shock oscillations that corrupt the entire flow unless additional dissipation is added. This dissipation can be difficult to localize to the area near the shock and can lead to inaccurate treatment of the turbulence. Modern high-resolution shock-capturing methods usually use upwind algorithms to provide the dissipation necessary to stabilize shocks. However, this upwind dissipation can also lead to an unphysical rate of decay of the turbulence. This paper discusses a hybrid method for simulating turbulent flows with strong shocks that couples a high-order central difference scheme with a high-resolution shock-capturing method. The shock-capturing method is used only in the vicinity of discontinuities in the flow, whereas the central difference scheme is used in the remainder of the computational domain. Results of this new method will be shown for a variety of test problems. Preliminary results for a realistic application involving detonation in gas-particle flows will also be presented.

  2. Uso de leitos cultivados de fluxo vertical por batelada no pós-tratamento de efluente de reator anaeróbio compartimentado Post-treatment of effluent of anaerobic baffled reactor using batchwise vertical flow constructed wetland beds

    Directory of Open Access Journals (Sweden)

    Marcelo Mazzola


    Full Text Available Neste trabalho avaliou-se o desempenho de um Reator Anaeróbio Compartimentado (RAC de duas câmaras em série, seguido de três leitos cultivados (constructed wetlands de fluxo vertical por batelada. A unidade experimental, em escala piloto, foi instalada na Faculdade de Engenharia Agrícola - UNICAMP, Campinas, SP, Brasil. O volume total do reator era de 2,3 m³ (TDH de 12 h. O efluente do RAC foi tratado em três leitos, dois cultivados com macrófitas (gêneros Typha sp. e Eleocharis sp. e um utilizado como controle (não cultivado. Os leitos, com 2,0 m³ cada um e brita #2 (24 - 35 mm como meio suporte, operaram com fluxo vertical por batelada (com tempos de reação de 24, 48, 72 e 96 h. Na avaliação do RAC, observou-se tendência de estabilização dos parâmetros pH, alcalinidade, ácidos voláteis, sólidos sedimentáveis e suspensos totais, porém a remoção de DQO revelou-se limitada (50%. Nos leitos cultivados o aumento do tempo de reação (até 72 h foi acompanhado pelo aumento de remoção de turbidez, DQO, fósforo e nitrato. O melhor desempenho de remoção de fósforo total foi obtido no leito vegetado com Typha sp para os tempos de 72 e 96 h, respectivamente, de 30 e 25%.This study evaluated the performance of vertical constructed wetlands treating effluent of anaerobic baffled reactor. The anaerobic reactor volume was 2.3 m³; it was operated with daily flow of 4.6 m³ (12 hours Hydraulic Retention Time. The reactor effluent was split into three wetlands beds, two of them cultivated with macrophytes (Typha sp. and Eleocharis sp., and one control. The wetlands were operated as a batch reactor. The medium utilized was gravel, the size ranging from 7 to 12 mm. The reaction time for each cycle (filling - reaction - drainage was 24, 48, 72, and 96 h. The anaerobic reactor achieved the following removal rates: settable solids, 93%; suspended solids, 80%; and COD 39%. The increase in reaction time (up to 72 h for the constructed

  3. Physics of Traffic Flow (United States)

    Davis, L. C.


    The Texas A&M Transportation Institute estimated that traffic congestion cost the United States 121 billion in 2011 (the latest data available). The cost is due to wasted time and fuel. In addition to accidents and road construction, factors contributing to congestion include large demand, instability of high-density free flow and selfish behavior of drivers, which produces self-organized traffic bottlenecks. Extensive data collected on instrumented highways in various countries have led to a better understanding of traffic dynamics. From these measurements, Boris Kerner and colleagues developed a new theory called three-phase theory. They identified three major phases of flow observed in the data: free flow, synchronous flow and wide moving jams. The intermediate phase is called synchronous because vehicles in different lanes tend to have similar velocities. This congested phase, characterized by lower velocities yet modestly high throughput, frequently occurs near on-ramps and lane reductions. At present there are only two widely used methods of congestion mitigation: ramp metering and the display of current travel-time information to drivers. To find more effective methods to reduce congestion, researchers perform large-scale simulations using models based on the new theories. An algorithm has been proposed to realize Wardrop equilibria with real-time route information. Such equilibria have equal travel time on alternative routes between a given origin and destination. An active area of current research is the dynamics of connected vehicles, which communicate wirelessly with other vehicles and the surrounding infrastructure. These systems show great promise for improving traffic flow and safety.

  4. Development of a Linear Flow Channel Reactor for sulphur removal ...

    African Journals Online (AJOL)


    Sep 23, 2013 ... Channel Reactor in an acid mine drainage passive treatment environment have been undertaken in field studies. Keywords: floating sulphur biofilms, acid mine drainage, AMD passive treatment, linear flow channel reactor, sulphur .... then filtered through a 0.45 µm nylon filter before being passed through ...

  5. The phenomenon of information a conceptual approach to information flow

    CERN Document Server

    Pérez-Montoro, Mario


    This study examines critically major theories of information and offers an original treatment of information flows that attempts to remedy weaknesses in earlier treatments and may serve as a basis on which a satisfactory analysis of the concept of information can be developed.

  6. Low flow hydrology: a review

    CSIR Research Space (South Africa)

    Smakhtin, VU


    Full Text Available prolonged dry weather’. This definition does not make a clear distinction between low flows and droughts. Low flows is a seasonal phenomenon, and an integral component of a flow regime of any river. Drought, on the other hand, is a natural event...-flow generating mechanisms is rather limited. At the same time, identification of relative importance of various low-flow generation mechanisms and factors should ideally precede any low-flow analysis and also form an integral part of developing plans...

  7. Measurement of LBE flow velocity profile by UDVP

    International Nuclear Information System (INIS)

    Kikuchi, Kenji; Takeda, Yasushi; Obayashi, Hiroo; Tezuka, Masao; Sato, Hiroshi


    Measurements of liquid metal lead-bismuth eutectic (LBE), flow velocity profile were realized in the spallation neutron source target model by the ultrasonic Doppler velocity profiler (UVDP) technique. So far, it has not been done well, because both of poor wetting property of LBE with stainless steels and poor performance of supersonic probes at high temperatures. The measurement was made for a return flow in the target model, which has coaxially arranged annular and tube channels, in the JAEA Lead Bismuth Loop-2 (JLBL-2). The surface treatment of LBE container was examined. It was found that the solder coating was effective to enhance an intensity of reflected ultrasonic wave. This treatment has been applied to the LBE loop, which was operated up to 150 deg. C. The electro magnetic pump generates LBE flow and the flow rate was measured by the electro magnetic flow meter. By changing the flow rate of LBE, velocity profiles in the target were measured. It was confirmed that the maximum velocity in the time-averaged velocity distribution on the target axis was proportional to the flow rate measured by the electro magnetic flow meter

  8. Pressure Driven Poiseuille Flow

    DEFF Research Database (Denmark)

    Stotz, Ingo Leonardo; Iaffaldano, Giampiero; Davies, D. Rhodri


    and lithosphere mutually exchange, by virtue of Newton's third law of motion. In light of these constraints, the notion that subduction is the main driver of present–day Pacific plate motion becomes somewhat unviable, as the pulling force that would be required by slabs exceeds the maximum available from......The Pacific plate is thought to be driven mainly by slab pull, associated with subduction along the Aleutians–Japan, Marianas–Izu–Bonin and Tonga–Kermadec trenches. This implies that viscous flow within the sub–Pacific asthenosphere is mainly generated by overlying plate motion (i.e. Couette flow......), and that the associated shear–stresses at the lithosphere's base are resisting such motion. Recent studies on glacial isostatic adjustment and lithosphere dynamics provide tighter constraints on the viscosity and thickness of Earth's asthenosphere and, therefore, on the amount of shear–stress that asthenosphere...

  9. Fracture flow code

    International Nuclear Information System (INIS)

    Dershowitz, W; Herbert, A.; Long, J.


    The hydrology of the SCV site will be modelled utilizing discrete fracture flow models. These models are complex, and can not be fully cerified by comparison to analytical solutions. The best approach for verification of these codes is therefore cross-verification between different codes. This is complicated by the variation in assumptions and solution techniques utilized in different codes. Cross-verification procedures are defined which allow comparison of the codes developed by Harwell Laboratory, Lawrence Berkeley Laboratory, and Golder Associates Inc. Six cross-verification datasets are defined for deterministic and stochastic verification of geometric and flow features of the codes. Additional datasets for verification of transport features will be documented in a future report. (13 figs., 7 tabs., 10 refs.) (authors)

  10. Structural power flow measurement

    Energy Technology Data Exchange (ETDEWEB)

    Falter, K.J.; Keltie, R.F.


    Previous investigations of structural power flow through beam-like structures resulted in some unexplained anomalies in the calculated data. In order to develop structural power flow measurement as a viable technique for machine tool design, the causes of these anomalies needed to be found. Once found, techniques for eliminating the errors could be developed. Error sources were found in the experimental apparatus itself as well as in the instrumentation. Although flexural waves are the carriers of power in the experimental apparatus, at some frequencies longitudinal waves were excited which were picked up by the accelerometers and altered power measurements. Errors were found in the phase and gain response of the sensors and amplifiers used for measurement. A transfer function correction technique was employed to compensate for these instrumentation errors.

  11. Nanocatalysis in Flow. (United States)

    Ricciardi, Roberto; Huskens, Jurriaan; Verboom, Willem


    Nanocatalysis in flow is catalysis by metallic nanoparticles (NPs; 1-50 nm) performed in microstructured reactors. These catalytic processes make use of the enhanced catalytic activity and selectivity of NPs and fulfill the requirements of green chemistry. Anchoring catalytically active metal NPs within a microfluidic reactor enhances the reagent/catalyst interaction, while avoiding diffusion limitations experienced in classical approaches. Different strategies for supporting NPs are reviewed herein, namely, packed-bed reactors, monolithic flow-through reactors, wall catalysts, and a selection of novel approaches (NPs embedded on nanotubes, nanowires, catalytic membranes, and magnetic NPs). Through a number of catalytic reactions, such as hydrogenations, oxidations, and cross-coupling reactions, the advantages and possible drawbacks of each approach are illustrated. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Slow viscous flow

    CERN Document Server

    Langlois, William E


    Leonardo wrote, 'Mechanics is the paradise of the mathematical sciences, because by means of it one comes to the fruits of mathematics' ; replace 'Mechanics' by 'Fluid mechanics' and here we are." -    from the Preface to the Second Edition Although the exponential growth of computer power has advanced the importance of simulations and visualization tools for elaborating new models, designs and technologies, the discipline of fluid mechanics is still large, and turbulence in flows remains a challenging problem in classical physics. Like its predecessor, the revised and expanded Second Edition of this book addresses the basic principles of fluid mechanics and solves fluid flow problems where viscous effects are the dominant physical phenomena. Much progress has occurred in the nearly half a century that has passed since the edition of 1964. As predicted, aspects of hydrodynamics once considered offbeat have risen to importance. For example, the authors have worked on problems where variations in viscosity a...

  13. Optimal Power Flow Pursuit

    Energy Technology Data Exchange (ETDEWEB)

    Dall' Anese, Emiliano; Simonetto, Andrea


    This paper considers distribution networks featuring inverter-interfaced distributed energy resources, and develops distributed feedback controllers that continuously drive the inverter output powers to solutions of AC optimal power flow (OPF) problems. Particularly, the controllers update the power setpoints based on voltage measurements as well as given (time-varying) OPF targets, and entail elementary operations implementable onto low-cost microcontrollers that accompany power-electronics interfaces of gateways and inverters. The design of the control framework is based on suitable linear approximations of the AC power-flow equations as well as Lagrangian regularization methods. Convergence and OPF-target tracking capabilities of the controllers are analytically established. Overall, the proposed method allows to bypass traditional hierarchical setups where feedback control and optimization operate at distinct time scales, and to enable real-time optimization of distribution systems.

  14. Lateral flow assays. (United States)

    Koczula, Katarzyna M; Gallotta, Andrea


    Lateral flow assays (LFAs) are the technology behind low-cost, simple, rapid and portable detection devices popular in biomedicine, agriculture, food and environmental sciences. This review presents an overview of the principle of the method and the critical components of the assay, focusing on lateral flow immunoassays. This type of assay has recently attracted considerable interest because of its potential to provide instantaneous diagnosis directly to patients. The range and interpretation of results and parameters used for evaluation of the assay will also be discussed. The main advantages and disadvantages of LFAs will be summarized and relevant future improvements to testing devices and strategies will be proposed. Finally, the major recent advances and future diagnostic applications in the LFA field will be explored. © 2016 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  15. Lateral flow assays (United States)

    Koczula, Katarzyna M.


    Lateral flow assays (LFAs) are the technology behind low-cost, simple, rapid and portable detection devices popular in biomedicine, agriculture, food and environmental sciences. This review presents an overview of the principle of the method and the critical components of the assay, focusing on lateral flow immunoassays. This type of assay has recently attracted considerable interest because of its potential to provide instantaneous diagnosis directly to patients. The range and interpretation of results and parameters used for evaluation of the assay will also be discussed. The main advantages and disadvantages of LFAs will be summarized and relevant future improvements to testing devices and strategies will be proposed. Finally, the major recent advances and future diagnostic applications in the LFA field will be explored. PMID:27365041

  16. Fast X-ray imaging of two-phase flows: Application to cavitating flows

    International Nuclear Information System (INIS)

    Khlifa, Ilyass


    A promising method based on fast X-ray imaging has been developed to investigate the dynamics and the structure of complex two-phase flows. It has been applied in this work on cavitating flows created inside a Venturi-type test section and helped therefore to better understand flows inside cavitation pockets. Seeding particles were injected into the flow to trace the liquid phase. Thanks to the characteristics of the beam provided by the APS synchrotron (Advance Photon Source, USA), high definition X-ray images of the flow containing simultaneously information for both liquid and vapour were obtained. Velocity fields of both phases were thus calculated using image cross-correlation algorithms. Local volume fractions of vapour have also been obtained using local intensities of the images. Beforehand however, image processing is required to separate phases for velocity measurements. Validation methods of all applied treatments were developed, they allowed to characterise the measurement accuracy. This experimental technique helped us to have more insight into the dynamic of cavitating flows and especially demonstrates the presence of significant slip velocities between phases. (author)

  17. Flow og fordybelse

    DEFF Research Database (Denmark)

    Andersen, Frans Ørsted


    Artiklen handler om flow og fordybelse i et nyt tværfagligt / naturfagligt undervisningskoncept, "Overvågningens dilemma", til brug i folkeskolens 7.-9.kl. og på gymnasiale uddannelser. Konceptet sætter fokus på den overvågning der foregår og er mulig i nutidens IT og hi-tec samfund og der arbejd...

  18. Cash flow analysis

    International Nuclear Information System (INIS)



    This chapter addresses the cash flow analysis of dual-purpose power plants. The topics discussed include the impact of inflation (including the relative inflation of individual cost components such as purchased power, supplemental power, standby charges, buy back rate, heating fuel costs, power plants costs, staffing, maintenance, insurance, and administrative charges), controlling costs, purchased power and fuel price projections, varying the assumptions, financing, and modeling of tax impacts

  19. Divergent flow isoelectric focusing

    Czech Academy of Sciences Publication Activity Database

    Šlais, Karel


    Roč. 29, č. 12 (2008), s. 2451-2457 ISSN 0173-0835 R&D Projects: GA AV ČR IAAX00310701; GA ČR GA203/06/1179 Institutional research plan: CEZ:AV0Z40310501 Keywords : isoelectric focusing * divergent flow * pI markers Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.509, year: 2008

  20. TensorFlow Distributions


    Dillon, Joshua V.; Langmore, Ian; Tran, Dustin; Brevdo, Eugene; Vasudevan, Srinivas; Moore, Dave; Patton, Brian; Alemi, Alex; Hoffman, Matt; Saurous, Rif A.


    The TensorFlow Distributions library implements a vision of probability theory adapted to the modern deep-learning paradigm of end-to-end differentiable computation. Building on two basic abstractions, it offers flexible building blocks for probabilistic computation. Distributions provide fast, numerically stable methods for generating samples and computing statistics, e.g., log density. Bijectors provide composable volume-tracking transformations with automatic caching. Together these enable...

  1. Measurement of flow in supercritical flow regime using cutthroat flumes

    Indian Academy of Sciences (India)

    [6] Smith R E, Chery D L, Renard K G and Gwinn W R 1981. Supercritical flow flumes for measuring sediment-laden flow,. United States Department of Agriculture, Technical Bulletin number 1655. [7] Manekar V L, Porey P D and Ingle R N 2007 Discharge rela- tion for cutthroat flume under free flow condition. J. Irrig.

  2. Low flow Coriolis flow controller with piezo operated control valve

    NARCIS (Netherlands)

    Katerberg, M.R.; Ratering, G.H.J.M.; Platenkamp, T.H.; van de Geest, J.W.; Klein Hesselink, S.; Lötters, Joost Conrad


    We developed a compact conventional steel tube Coriolis mass flow controller for low flow rates down to 10mg/min and up to 3g/min in one instrument. The mechanical construction of the flow controller has been optimized to have a low internal dead volume for control speed and stability. An on board

  3. Convective heat flow probe (United States)

    Dunn, James C.; Hardee, Harry C.; Striker, Richard P.


    A convective heat flow probe device is provided which measures heat flow and fluid flow magnitude in the formation surrounding a borehole. The probe comprises an elongate housing adapted to be lowered down into the borehole; a plurality of heaters extending along the probe for heating the formation surrounding the borehole; a plurality of temperature sensors arranged around the periphery of the probe for measuring the temperature of the surrounding formation after heating thereof by the heater elements. The temperature sensors and heater elements are mounted in a plurality of separate heater pads which are supported by the housing and which are adapted to be radially expanded into firm engagement with the walls of the borehole. The heat supplied by the heater elements and the temperatures measured by the temperature sensors are monitored and used in providing the desired measurements. The outer peripheral surfaces of the heater pads are configured as segments of a cylinder and form a full cylinder when taken together. A plurality of temperature sensors are located on each pad so as to extend along the length and across the width thereof, with a heating element being located in each pad beneath the temperature sensors. An expansion mechanism driven by a clamping motor provides expansion and retraction of the heater pads and expandable packer-type seals are provided along the probe above and below the heater pads.

  4. Conversational flow promotes solidarity. (United States)

    Koudenburg, Namkje; Postmes, Tom; Gordijn, Ernestine H


    Social interaction is fundamental to the development of various aspects of "we-ness". Previous research has focused on the role the content of interaction plays in establishing feelings of unity, belongingness and shared reality (a cluster of variables referred to as solidarity here). The present paper is less concerned with content, but focuses on the form of social interaction. We propose that the degree to which conversations flow smoothly or not is, of itself, a cue to solidarity. We test this hypothesis in samples of unacquainted and acquainted dyads who communicate via headsets. Conversational flow is disrupted by introducing a delay in the auditory feedback (vs. no delay). Results of three studies show that smoothly coordinated conversations (compared with disrupted conversations and a control condition) increase feelings of belonging and perceptions of group entitativity, independently of conversation content. These effects are driven by the subjective experience of conversational flow. Our data suggest that this process occurs largely beyond individuals' control. We conclude that the form of social interaction is a powerful cue for inferring group solidarity. Implications for the impact of modern communication technology on developing a shared social identity are discussed.

  5. Tratamento endovascular de aneurisma da artéria renal por embolização com micromolas preservando o fluxo sangüíneo renal: relato de caso Endovascular treatment of renal artery aneurysm using microcoil embolization and renal blood flow preservation: case report

    Directory of Open Access Journals (Sweden)

    Marco Aurélio Cardozo


    Full Text Available O tratamento endovascular da doença aneurismática da artéria renal tem sido, cada vez mais, aceito como uma alternativa à cirurgia convencional, especialmente em casos de aneurismas complexos intra-parenquimatosos ou que comprometam a bifurcação da artéria renal. Os autores relatam a experiência do tratamento endovascular de uma paciente com aneurisma sacular da bifurcação da artéria renal direita, associado à hipertensão renovascular de difícil controle. Foi realizada a cateterização seletiva da artéria renal, com a inserção de micromolas no saco aneurismático. O aneurisma foi completamente ocluído com preservação total do fluxo sanguíneo renal. A evolução clínica foi satisfatória com redução significativa das medicações anti-hipertensivas. A angio-tomografia de controle, após o oitavo mês do procedimento, confirmou o sucesso do tratamento.Endovascular treatment of renal artery aneurysmal disease has been increasingly accepted as an alternative to conventional surgery, especially in cases of renal artery bifurcation or complex intrarenal aneurysms. The authors report a case of endovascular treatment of a saccular aneurysm of the right renal artery bifurcation associated with poorly controlled renovascular hypertension. Selective catheterization of the renal artery was performed and microcoils were inserted into the aneurysmal sac. The aneurysm was completely obliterated with total preservation of renal blood flow. Clinical evolution was satisfactory with significant reduction in anti-hypertensive drugs. Control tomographic angiography, after eight months, confirmed treatment success.

  6. Towards Sustainable Flow Management - Introduction

    DEFF Research Database (Denmark)

    Moss, Timothy; Elle, Morten


    Outlines the conditions for the three Local Agenda 21 case-studies in the Sustainable Flow Management Project......Outlines the conditions for the three Local Agenda 21 case-studies in the Sustainable Flow Management Project...

  7. Towards Sustainable Flow Management - Introduction

    DEFF Research Database (Denmark)

    Moss, Timothy; Elle, Morten


    Outlines the conditions for the three Local Agenda 21 case-studies in the Sustainable Flow Management project......Outlines the conditions for the three Local Agenda 21 case-studies in the Sustainable Flow Management project...

  8. Flow list and test results (United States)

    U.S. Environmental Protection Agency — These data accompany the manuscript 'Critical Review of Elementary Flows in LCA Data'. Each file presents a subgroup of the elementary flows (data used for analysis)...

  9. Asymmetric reactions in continuous flow

    Directory of Open Access Journals (Sweden)

    Xiao Yin Mak


    Full Text Available An overview of asymmetric synthesis in continuous flow and microreactors is presented in this review. Applications of homogeneous and heterogeneous asymmetric catalysis as well as biocatalysis in flow are discussed.

  10. Measuring Your Peak Flow Rate (United States)

    ... your child so they can help monitor your child's asthma symptoms . Why Should I Measure My Flow Rate? ... help parents determine what might be triggering their child's asthma. How Do You Use a Peak Flow Meter? ...

  11. Radial flow pulse jet mixer (United States)

    VanOsdol, John G.


    The disclosure provides a pulse jet mixing vessel for mixing a plurality of solid particles. The pulse jet mixing vessel is comprised of a sludge basin, a flow surface surrounding the sludge basin, and a downcoming flow annulus between the flow surface and an inner shroud. The pulse jet mixing vessel is additionally comprised of an upper vessel pressurization volume in fluid communication with the downcoming flow annulus, and an inner shroud surge volume separated from the downcoming flow annulus by the inner shroud. When the solid particles are resting on the sludge basin and a fluid such as water is atop the particles and extending into the downcoming flow annulus and the inner shroud surge volume, mixing occurs by pressurization of the upper vessel pressurization volume, generating an inward radial flow over the flow surface and an upwash jet at the center of the sludge basin.

  12. The Control of Junction Flows

    National Research Council Canada - National Science Library

    Smith, Charles


    An experimental study of the effects of spatially-limited (i.e. localized) surface suction on unsteady laminar and turbulent junction flows was performed using hydrogen bubble flow visualization and Particle Image Velocimetry (PIV...

  13. [Outpatient treatment for patients with eating disorders]. (United States)


    In the treatment of eating disorders, patients in either the acute or chronic stage are generally treated on outpatient basis as much as possible in the living condition of daily life. This paper describes the flow of diagnosis and treatment, first examination and introduction into treatment, way of parents treating their child, parental counseling, criteria for admission (immediate hospitalization or not), and outpatient therapy.

  14. Investigations on flow reversal in stratified horizontal flow

    International Nuclear Information System (INIS)

    Staebler, T.; Meyer, L.; Schulenberg, T.; Laurien, E.


    The phenomena of flow reversal in stratified flows are investigated in a horizontal channel with application to the Emergency Core Cooling System (ECCS) in Pressurized Water Reactors (PWR). In case of a Loss-of-Coolant-Accident (LOCA), coolant can be injected through a secondary pipe within the feeding line of the primary circuit, the so called hot leg, counter-currently to the steam flow. It is essential that the coolant reaches the reactor core to prevent overheating. Due to high temperatures in such accident scenarios, steam is generated in the core, which escapes from the reactor vessel through the hot leg. In case of sufficiently high steam flow rates, only a reduced amount of coolant or even no coolant will be delivered to the reactor core. The WENKA test facility at the Institute for Nuclear and Energy Technologies (IKET) at Forschungszentrum Karlsruhe is capable to investigate the fluid dynamics of two-phase flows in such scenarios. Water and air flow counter-currently in a horizontal channel made of clear acrylic glass to allow full optical access. Flow rates of water and air can be varied independently within a wide range. Once flow reversal sets in, a strong hysteresis effect must be taken into account. This was quantified during the present investigations. Local experimental data are needed to expand appropriate models on flow reversal in horizontal two-phase flow and to include them into numerical codes. Investigations are carried out by means of Particle Image Velocimetry (PIV) to obtain local flow velocities without disturbing the flow. Due to the wavy character of the flow, strong reflections at the interfacial area must be taken into account. Using fluorescent particles and an optical filter allows eliminating the reflections and recording only the signals of the particles. The challenges in conducting local investigations in stratified wavy flows by applying optical measurement techniques are discussed. Results are presented and discussed allowing

  15. Information Flow in Logical Environments


    Kent, Robert E.


    This paper describes information flow within logical environments. The theory of information flow, the logic of distributed systems, was first defined by Barwise and Seligman (Information Flow: The Logic of Distributed Systems. 1997). Logical environments are a semantic-oriented version of institutions. The theory of institutions, which was initiated by Goguen and Burstall (Institutions: Abstract Model Theory for Specification and Programming. 1992), is abstract model theory. Information flow...

  16. Intra-aneurysmal flow patterns: illustrative comparison among digital subtraction angiography, optical flow, and computational fluid dynamics. (United States)

    Brina, O; Ouared, R; Bonnefous, O; van Nijnatten, F; Bouillot, P; Bijlenga, P; Schaller, K; Lovblad, K-O; Grünhagen, T; Ruijters, D; Pereira, V Mendes


    Digital subtraction angiography is the gold standard vascular imaging and it is used for all endovascular treatment of intracranial anerysms. Optical flow imaging has been described as a potential method to evaluate cerebral hemodynamics through DSA. In this study, we aimed to compare the flow patterns measured during angiography, by using an optical flow method, with those measured by using computational fluid dynamics in intracranial aneurysms. A consecutive series of 21 patients harboring unruptured saccular intracranial aneurysms who underwent diagnostic angiography before treatment was considered. High-frame-rate digital subtraction angiography was performed to obtain an intra-aneurysmal velocity field by following the cardiac-modulated contrast wave through the vascular structures by using optical flow principles. Additionally, computational fluid dynamics modeling was performed for every case by using patient-specific inlet-boundary conditions measured with the optical flow method from both DSA and 3D rotational angiography datasets. Three independent observers compared qualitatively both the inflow direction and the apparent recirculation in regular DSA, optical flow images, and computational fluid dynamics flow patterns for each patient; κ statistics were estimated. We included 21 patients. In 14 of these 21, the flow patterns were conclusive and matching between the optical flow images and computational fluid dynamics within the same projection view (κ = .91). However, in only 8 of these 14 patients the optical flow images were conclusive and matching regular DSA images (observer κ = 0.87). In 7 of the 21 patients, the flow patterns in the optical flow images were inconclusive, possibly due to improper projection angles. The DSA-based optical flow technique was considered qualitatively consistent with computational fluid dynamics outcomes in evaluating intra-aneurysmal inflow direction and apparent recirculation. Moreover, the optical flow technique

  17. Simulation of gas compressible flow by free surface water flow

    International Nuclear Information System (INIS)

    Altafini, C.R.; Silva Ferreira, R.T. da


    The analogy between the water flow with a free surface and the compressible fluid flow, commonly called hydraulic analogy, is analyzed and its limitations are identified. The water table is the equipment used for this simulation, which allows the quatitative analysis of subsonic and supersonic flow with a low cost apparatus. The hydraulic analogy is applied to subsonic flow around circular cylinders and supersonic flow around cones. The results are compared with available theoretical and experimental data and a good agreement is achieved. (Author) [pt

  18. Risk assessment future cash flows


    Chachina H. G.


    This article is about risk assessment in planning future cash flows. Discount rate in DCF-model must include four factors: risk cash flow, inflation, value of investments, turnover assets. This has an influence net present value cash flow and make his incomparable.

  19. Peak flow meter use - slideshow (United States)

    ... page: // Peak flow meter use - Series—Peak flow meter use - part one To use the sharing ... slide 7 out of 7 Overview A peak flow meter helps you check how well your asthma ...

  20. Flow shapes and higher harmonics in anisotropic transverse collective flow

    Energy Technology Data Exchange (ETDEWEB)

    Argintaru, Danut; Baban, Valerica [Constanta Maritime University, Faculty of Navigation and Naval Transport, Constanta (Romania); Besliu, Calin; Jipa, Alexandru; Grossu, Valeriu [University of Bucharest, Faculty of Physics, Bucharest (Romania); Esanu, Tiberiu; Cherciu, Madalin [Institute of Space Sciences Bucharest-Magurele, Bucharest (Romania)


    In this paper we show that by using a jet-finder algorithm (the Anti-k{sub T} one) on UrQMD/C simulated (Au+Au at 4, 10 and 15A GeV) collisions, we can identify different flow shape structures (single flow stream events, two flow streams events, three flow streams events, etc.) and order the bulk of events in equivalence flow shape classes. Considering these flow streams as the main directions of anisotropic transverse flow, we show that the Fourier coefficients v{sub n} of anisotropic flow are better emphasized when we analyze the different event flow shape classes than when the events are mixed. Also, if we do not know the real orientation of the reaction plane, we can use as reference the Flow stream 1 - the main particle flow stream - orientation (Ψ{sub Flowstream} {sub 1}) to highlight the initial shape of the participant nuclear matter in a central to peripheral collision, and the orientation of the participant plane of order n. (orig.)

  1. Gas flow meter and method for measuring gas flow rate (United States)

    Robertson, Eric P.


    A gas flow rate meter includes an upstream line and two chambers having substantially equal, fixed volumes. An adjustable valve may direct the gas flow through the upstream line to either of the two chambers. A pressure monitoring device may be configured to prompt valve adjustments, directing the gas flow to an alternate chamber each time a pre-set pressure in the upstream line is reached. A method of measuring the gas flow rate measures the time required for the pressure in the upstream line to reach the pre-set pressure. The volume of the chamber and upstream line are known and fixed, thus the time required for the increase in pressure may be used to determine the flow rate of the gas. Another method of measuring the gas flow rate uses two pressure measurements of a fixed volume, taken at different times, to determine the flow rate of the gas.

  2. Virus movement in soil during saturated and unsaturated flow. (United States)

    Lance, J C; Gerba, C P


    Virus movement in soil during saturated and unsaturated flow was compared by adding poliovirus to sewage water and applying the water at different rates to a 250-cm-long soil column equipped with ceramic samplers at different depths. Movement of viruses during unsaturated flow of sewage through soil columns was much less than during saturated flow. Viruses did not move below the 40-cm level when sewage water was applied at less than the maximum infiltration rate; virus penetration in columns flooded with sewage was at least 160 cm. Therefore, virus movement in soils irrigated with sewage should be less than in flooded groundwater recharge basins or in saturated soil columns. Management of land treatment systems to provide unsaturated flow through the soil should minimize the depth of virus penetration. Differences in virus movement during saturated and unsaturated flow must be considered in the development of any model used to simulate virus movement in soils.

  3. Dynamics of Supercritical Flows (United States)


    Joncas and Maslow (53) performed a linear stability study of a compressible coaxial jet with velocity and temperature profiles characteristic of a...interface d‟une couche de mélange liquide-gaz”, Thèse de Doctorat, Université Joseph Fourier, Grenoble, 1997. 53. Perrault-Joncas, D., Maslowe , S. A...characteristics of the flow (Sevilla et al. [35], Perrault-Joncas and Maslowe [49]). Sevilla et al. [35] investigate the effect of outer to inner jet

  4. Providing Compassion through Flow

    Directory of Open Access Journals (Sweden)

    Lydia Royeen


    Full Text Available Meg Kral, MS, OTR/L, CLT, is the cover artist for the Summer 2015 issue of The Open Journal of Occupational Therapy. Her untitled piece of art is an oil painting and is a re-creation of a photograph taken while on vacation. Meg is currently supervisor of outpatient services at Rush University Medical Center. She is lymphedema certified and has a specific interest in breast cancer lymphedema. Art and occupational therapy serve similar purposes for Meg: both provide a sense of flow. She values the outcomes, whether it is a piece of art or improved functional status

  5. Sulphur flows on Io

    International Nuclear Information System (INIS)

    Sagan, C.


    Voyager 1 close-encounter photomosaics have clarified both the coloration of Io and its surface variation. These colour patterns seem explicable in terms of liquid sulphur produced in ionian volcanoes and solfataras and quenched at Io ambient temperatures approximately equal to 135 K. The liquid sulphur flow fronts and frozen rivers which appear in the Voyager images are discussed. It is argued that the volcanic deposition rates and the vapour pressure over sulphur melts are both consistent with the notion that the surface of Io changes significantly in geologically very short periods of time. (UK)

  6. Forecasting freight flows

    DEFF Research Database (Denmark)

    Lyk-Jensen, Stéphanie


    model. The analysis uses a structural relationship to explain the structure of the exchange of the goods—a relationship that can be used in the year of forecast. This article also provides a new methodology for converting monetary aggregates into quantity aggregates. The resulting commodity growth rates....... This article models long-term dynamic physical trade flows and estimates a dynamic panel data model for foreign trade for the EU15 and two countries from the EFTA (European Free Trade Association) 1967–2002. The analysis suggests that a dynamic three-way-effects gravity equation is the best-fitted econometric...

  7. Diffusion or bulk flow

    DEFF Research Database (Denmark)

    Schulz, Alexander


    assimilate movement includes an apoplasmic step, this mode is called apoplasmic loading. Well established is also the polymer-trap loading mode, where the phloem-transport sugars are raffinose-family oligomers in herbaceous plants. Also this mode depends on the investment of energy, here for sugar...... is currently matter of discussion, called passive symplasmic loading. Based on the limited material available, this review compares the different loading modes and suggests that diffusion is the driving force in apoplasmic loaders, while bulk flow plays an increasing role in plants having a continuous...

  8. Experimental techniques in unsteady flows (United States)

    Oldfield, M. L. G.


    Notes for four lectures intended as a practical user guide to some unsteady aerodynamic flow experimental measurement techniques are presented. Unsteady flows to be measured, including frequency and length scale, large scale unsteadiness, turbulence, boundary layer transition, shear layers and wakes, periodically time varying flows, shock waves and vortex flows, are explained. Wind tunnel requirements, intrusive measurements by hot wire and film anemometry and pressure probes, and surface measurements are described. Optical techniques covered include Schlieren photography, shadowgraph, holography, laser anemometry and flow tracing. Instrumentation and data acquisition and processing of unsteady data, using frequency analysis by fast Fourier transforms, convolution and correlation are described.

  9. Overview of zonal flow physics

    International Nuclear Information System (INIS)

    Diamond, P.H.; Itoh, K.; Itoh, S.-I.; Hahm, T.S.


    Zonal flows, by which we mean azimuthally symmetric band-like shear flows, are ubiquitous phenomena in nature and the laboratory. It is now widely recognized that zonal flows are a key constituent in virtually all cases and regimes of drift wave turbulence, indeed, so much so that this classic problem is now frequently referred to as 'drift wave-zonal flow turbulence'. In this theory overview, we present new viewpoints and unifying concepts which facilitate understanding of zonal flow physics, via theory, computation and their confrontation with the results of laboratory experiment. Special emphasis is placed on identifying avenues for further progress. (author)

  10. Industrial energy-flow management

    International Nuclear Information System (INIS)

    Lampret, Marko; Bukovec, Venceslav; Paternost, Andrej; Krizman, Srecko; Lojk, Vito; Golobic, Iztok


    Deregulation of the energy market has created new opportunities for the development of new energy-management methods based on energy assets, risk management, energy efficiency and sustainable development. Industrial energy-flow management in pharmaceutical systems, with a responsible approach to sustainable development, is a complex task. For this reason, an energy-information centre, with over 14,000 online measured data/nodes, was implemented. This paper presents the energy-flow rate, exergy-flow rate and cost-flow rate diagrams, with emphasis on cost-flow rate per energy unit or exergy unit of complex pharmaceutical systems

  11. Treatment Options by Stage (Cervical Cancer) (United States)

    ... nearby lymph nodes are also removed. Artificial openings ( stoma ) are made for urine and stool to flow ... information on cancer prevention, detection, genetics, treatment, supportive care, and complementary and alternative medicine. Most summaries come ...

  12. Treatment Options by Stage (Vaginal Cancer) (United States)

    ... Nearby lymph nodes are also removed. Artificial openings ( stoma ) are made for urine and stool to flow ... information on cancer prevention, detection, genetics, treatment, supportive care, and complementary and alternative medicine. Most summaries come ...

  13. Treatment Options by Stage (Vulvar Cancer) (United States)

    ... nearby lymph nodes are also removed. Artificial openings ( stoma ) are made for urine and stool to flow ... information on cancer prevention, detection, genetics, treatment, supportive care, and complementary and alternative medicine. Most summaries come ...

  14. Treatment Methods for Kidney Failure in Children (United States)

    ... 5 hours. During treatment, the child can do homework, read, write, sleep, talk, or watch TV. Some ... treat these problems with adjustments to the dialysis solution prescription and the speed at which blood flows ...

  15. Experimental Study of Flow Through Carotid Aneurysms (United States)

    Masoomi, Faezeh; Mejia-Alvarez, Ricardo


    There is evidence that traditional endovascular techniques like coiling are not effective for treatment of wide-neck cerebral aneurysms. Flow Diverter Stents (FDS) have emerged as promising devices for treating complex aneurysms since they enable treatment of aneurysms that were considered untreatable before. Recent studies suggest a number of associated risks with FDS, including in-stent thrombosis, perianeurysmal edema, delayed hemorrhage, and perforator occlusions. Chong et al. simulated hemodynamic behavior using patient-specific data. From their study, it is possible to infer that the standard deviation of energy loss could be a good predictor for intervention success. The aim of this study is to investigate the flow in models of cerebral aneurysms before and after FDS insertion using PIV. These models will be based on actual clinical studies and will be fabricated with advanced additive manufacturing techniques. These data will then be used to explore flow parameters that could inform the likelihood of post-intervention aneurysm rupture, and help determine FDS designs that better suit any particular patient before its procedure.

  16. RIPPLE: A new model for incompressible flows with free surfaces (United States)

    Kothe, D. B.; Mjolsness, R. C.


    A new free surface flow model, RIPPLE, is summarized. RIPPLE obtains finite difference solutions for incompressible flow problems having strong surface tension forces at free surfaces of arbitrarily complex topology. The key innovation is the Continuum Surface Force (CSF) model which represents surface tension as a (strongly) localized volume force. Other features include a high-order momentum advection model, a volume-of-fluid free surface treatment, and an efficient two-step projection solution method. RIPPLE'S unique capabilities are illustrated with two example problems: low-gravity jet-induced tank flow, and the collision and coalescence of two cylindrical rods.

  17. RIPPLE - A new model for incompressible flows with free surfaces (United States)

    Kothe, D. B.; Mjolsness, R. C.


    A new free surface flow model, RIPPLE, is summarized. RIPPLE obtains finite difference solutions for incompressible flow problems having strong surface tension forces at free surfaces of arbitrarily complex topology. The key innovation is the continuum surface force model which represents surface tension as a (strongly) localized volume force. Other features include a higher-order momentum advection model, a volume-of-fluid free surface treatment, and an efficient two-step projection solution method. RIPPLE's unique capabilities are illustrated with two example problems: low-gravity jet-induced tank flow, and the collision and coalescence of two cylindrical rods.

  18. Ground vortex flow field investigation (United States)

    Kuhn, Richard E.; Delfrate, John H.; Eshleman, James E.


    Flow field investigations were conducted at the NASA Ames-Dryden Flow Visualization Facility (water tunnel) to investigate the ground effect produced by the impingement of jets from aircraft nozzles on a ground board in a STOL operation. Effects on the overall flow field with both a stationary and a moving ground board were photographed and compared with similar data found in other references. Nozzle jet impingement angles, nozzle and inlet interaction, side-by-side nozzles, nozzles in tandem, and nozzles and inlets mounted on a flat plate model were investigated. Results show that the wall jet that generates the ground effect is unsteady and the boundary between the ground vortex flow field and the free-stream flow is unsteady. Additionally, the forward projection of the ground vortex flow field with a moving ground board is one-third less than that measured over a fixed ground board. Results also showed that inlets did not alter the ground vortex flow field.

  19. Experimental investigation of cavity flows

    Energy Technology Data Exchange (ETDEWEB)

    Loeland, Tore


    This thesis uses LDV (Laser Doppler Velocimetry), PIV (Particle Image Velocimetry) and Laser Sheet flow Visualisation to study flow inside three different cavity configurations. For sloping cavities, the vortex structure inside the cavities is found to depend upon the flow direction past the cavity. The shape of the downstream corner is a key factor in destroying the boundary layer flow entering the cavity. The experimental results agree well with numerical simulations of the same geometrical configurations. The results of the investigations are used to find the influence of the cavity flow on the accuracy of the ultrasonic flowmeter. A method to compensate for the cavity velocities is suggested. It is found that the relative deviation caused by the cavity velocities depend linearly on the pipe flow. It appears that the flow inside the cavities should not be neglected as done in the draft for the ISO technical report on ultrasonic flowmeters. 58 refs., 147 figs., 2 tabs.

  20. Exotic RG flows from holography

    Energy Technology Data Exchange (ETDEWEB)

    Kiritsis, Elias [APC, Universite Paris 7, CNRS/IN2P3, CEA/IRFU, Obs. de Paris, Sorbonne Paris Cite (France); Crete Center for Theoretical Physics, Institute for Theoretical and Computational Physics, Department of Physics, University of Crete, Heraklion (Greece); Crete Center for Quantum Complexity and Nanotechnology, Department of Physics, University of Crete, Heraklion (Greece); Nitti, Francesco; Silva Pimenta, Leandro [APC, Universite Paris 7, CNRS/IN2P3, CEA/IRFU, Obs. de Paris, Sorbonne Paris Cite (France)


    Holographic RG flows are studied in an Einstein-dilaton theory with a general potential. The superpotential formalism is utilized in order to characterize and classify all solutions that are associated with asymptotically AdS space-times. Such solutions correspond to holographic RG flows and are characterized by their holographic β-functions. Novel solutions are found that have exotic properties from a RG point-of view. Some have β-functions that are defined patch-wise and lead to flows where the β-function changes sign without the flow stopping. Others describe flows that end in non-neighboring extrema in field space. Finally others describe regular flows between two minima of the potential and correspond holographically to flows driven by the VEV of an irrelevant operator in the UV CFT. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Multiphase flow models for hydraulic fracturing technology (United States)

    Osiptsov, Andrei A.


    The technology of hydraulic fracturing of a hydrocarbon-bearing formation is based on pumping a fluid with particles into a well to create fractures in porous medium. After the end of pumping, the fractures filled with closely packed proppant particles create highly conductive channels for hydrocarbon flow from far-field reservoir to the well to surface. The design of the hydraulic fracturing treatment is carried out with a simulator. Those simulators are based on mathematical models, which need to be accurate and close to physical reality. The entire process of fracture placement and flowback/cleanup can be conventionally split into the following four stages: (i) quasi-steady state effectively single-phase suspension flow down the wellbore, (ii) particle transport in an open vertical fracture, (iii) displacement of fracturing fluid by hydrocarbons from the closed fracture filled with a random close pack of proppant particles, and, finally, (iv) highly transient gas-liquid flow in a well during cleanup. The stage (i) is relatively well described by the existing hydralics models, while the models for the other three stages of the process need revisiting and considerable improvement, which was the focus of the author’s research presented in this review paper. For stage (ii), we consider the derivation of a multi-fluid model for suspension flow in a narrow vertical hydraulic fracture at moderate Re on the scale of fracture height and length and also the migration of particles across the flow on the scale of fracture width. At the stage of fracture cleanaup (iii), a novel multi-continua model for suspension filtration is developed. To provide closure relationships for permeability of proppant packings to be used in this model, a 3D direct numerical simulation of single phase flow is carried out using the lattice-Boltzmann method. For wellbore cleanup (iv), we present a combined 1D model for highly-transient gas-liquid flow based on the combination of multi-fluid and

  2. Experimental research of the couette flow with cross flow

    Directory of Open Access Journals (Sweden)

    Schmidt Marcus


    Full Text Available When a solid cylinder is rotating inside a hollow cylinder, a characteristic fluid flow occurs inside the gap between the two cylinders, caused by the adhesion of the fluid at the walls. This flow problem is widely known as the Couette-flow. If an additional flow entrances through a radial located feedhole at the outer hollow cylinder, there is an interaction between the cross flow and the Couette-flow. In result there are complex three dimensional flow structures in the gap at the area around the feedhole. These arising flow structures are closely related with the technical important flow inside the gap of hydrodynamic lubricated journal bearings. When the flow conditions inside the bearing gap are well explored and appreciated, it will be possible to give suggestions for constructive details like the design, the location and the dimension of the feedhole for longer lifecycles or an even more efficiently running. In this paper the test rig of the bearing model will be presented. Moreover some representative results from researches with a Laser-Doppler-Velocimeter (LDV in comparison with the output of three dimensional numerical simulations will be illustrated.

  3. Thermosensitive gas flow sensor

    International Nuclear Information System (INIS)

    Berlicki, T.; Osadnik, S.; Prociow, E.


    Results of investigations on thermal gas flow sensor have been presented. The sensor consists of three thin film resistors Si+Ta. The circuit was designed in the form of two bridges; one of them serves for measurement of the heater temperature, the second one for the measurement of temperature difference of peripheral resistors. The measurement of output voltage versus the rate of nitrogen flow at various power levels dissipated at the heater and various temperatures have been made. The measurements were carried out in three versions; (a) at constant temperature of the heater, (b) at constant power dissipated in the heater, controlled by the power of the heater, (c) at constant temperature of the heater controlled by the power dissipated in the peripheral resistors of the sensor. Due to measurement range it is advantageous to stabilize the temperature of the heater, especially by means of the power supplied to the peripheral resistors. In this case the wider measurement range can be obtained. (author)

  4. Radial flow heat exchanger (United States)

    Valenzuela, Javier


    A radial flow heat exchanger (20) having a plurality of first passages (24) for transporting a first fluid (25) and a plurality of second passages (26) for transporting a second fluid (27). The first and second passages are arranged in stacked, alternating relationship, are separated from one another by relatively thin plates (30) and (32), and surround a central axis (22). The thickness of the first and second passages are selected so that the first and second fluids, respectively, are transported with laminar flow through the passages. To enhance thermal energy transfer between first and second passages, the latter are arranged so each first passage is in thermal communication with an associated second passage along substantially its entire length, and vice versa with respect to the second passages. The heat exchangers may be stacked to achieve a modular heat exchange assembly (300). Certain heat exchangers in the assembly may be designed slightly differently than other heat exchangers to address changes in fluid properties during transport through the heat exchanger, so as to enhance overall thermal effectiveness of the assembly.

  5. Blood flow and microgravity (United States)

    Bureau, Lionel; Coupier, Gwennou; Dubois, Frank; Duperray, Alain; Farutin, Alexander; Minetti, Christophe; Misbah, Chaouqi; Podgorski, Thomas; Tsvirkun, Daria; Vysokikh, Mikhail


    The absence of gravity during space flight can alter cardio-vascular functions partially due to reduced physical activity. This affects the overall hemodynamics, and in particular the level of shear stresses to which blood vessels are submitted. Long-term exposure to space environment is thus susceptible to induce vascular remodeling through a mechanotransduction cascade that couples vessel shape and function with the mechanical cues exerted by the circulating cells on the vessel walls. Central to such processes, the glycocalyx - i.e. the micron-thick layer of biomacromolecules that lines the lumen of blood vessels and is directly exposed to blood flow - is a major actor in the regulation of biochemical and mechanical interactions. We discuss in this article several experiments performed under microgravity, such as the determination of lift force and collective motion in blood flow, and some preliminary results obtained in artificial microfluidic circuits functionalized with endothelium that offer interesting perspectives for the study of the interactions between blood and endothelium in healthy condition as well as by mimicking the degradation of glycocalyx caused by long space missions. A direct comparison between experiments and simulations is discussed. xml:lang="fr"

  6. UZ Flow Models and Submodels

    International Nuclear Information System (INIS)

    Y. Wu


    The purpose of this report is to document the unsaturated zone (UZ) flow models and submodels, as well as the flow fields that have been generated using the UZ flow model(s) of Yucca Mountain, Nevada. In this report, the term ''UZ model'' refers to the UZ flow model and the several submodels, which include tracer transport, temperature or ambient geothermal, pneumatic or gas flow, and geochemistry (chloride, calcite, and strontium) submodels. The term UZ flow model refers to the three-dimensional models used for calibration and simulation of UZ flow fields. This work was planned in the ''Technical Work Plan (TWP) for: Unsaturated Zone Flow Analysis and Model Report Integration'' (BSC 2004 [DIRS 169654], Section 1.2.7). The table of included Features, Events, and Processes (FEPs), Table 6.2-11, is different from the list of included FEPs assigned to this report in the ''Technical Work Plan for: Unsaturated Zone Flow Analysis and Model Report Integration'' (BSC 2004 [DIRS 169654], Table 2.1.5-1), as discussed in Section 6.2.6. The UZ model has revised, updated, and enhanced the previous UZ model (BSC 2001 [DIRS 158726]) by incorporating the repository design with new grids, recalibration of property sets, and more comprehensive validation effort. The flow fields describe fracture-fracture, matrix-matrix, and fracture-matrix liquid flow rates, and their spatial distributions as well as moisture conditions in the UZ system. These three-dimensional UZ flow fields are used directly by Total System Performance Assessment (TSPA). The model and submodels evaluate important hydrogeologic processes in the UZ as well as geochemistry and geothermal conditions. These provide the necessary framework to test hypotheses of flow and transport at different scales, and predict flow and transport behavior under a variety of climatic conditions. In addition, the limitations of the UZ model are discussed in Section 8.11

  7. Modeling flow inside an anaerobic digester by CFD techniques

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza, Alexandra Martinez; Jimenez, P. Amparo Lopez [Departmento do Ingenieria Hidralica y Medio Ambiente, Universitat Politecnica de Valencia, Camino de Vera S/N 46022 (Spain); Martinez, Tatiana Montoya; Monanana, Vincente Fajardo [Grupo Aquas de Valencia. Avenida Marques del Turia 19 46005 Valencia (Spain)


    Anaerobic processes are used to treat high strength organic wastewater as well as for the treatment of primary and secondary sludge from conventional wastewater treatment plants. In these processes, heterotrophic microorganisms convert biodegradable organic matter to methane and carbon dioxide in the absence of dissolved oxygen and nitrate. Some of the most important aspects of the design of anaerobic digesters are related to hydraulic considerations. In spite of its important role in performance, hydraulics of flow inside digesters has not been quantified or adequately characterized. In this contribution a three-dimensional steady-state computational fluid dynamics (CFD) simulation has been performed for a particular anaerobic digester, in order to visualize the flow patterns. Flow and velocities profiles have been represented inside the digester to identify possible dead zones or stratifications. The geometry of a real digester installed in Valencia Waste Water Treatment Plant (located in Quart-Benager, Valencia, Spain) has been used in order to consider the proposed methodology.

  8. Modeling metal stocks and flows: a review of dynamic material flow analysis methods. (United States)

    Müller, Esther; Hilty, Lorenz M; Widmer, Rolf; Schluep, Mathias; Faulstich, Martin


    Dynamic material flow analysis (MFA) is a frequently used method to assess past, present, and future stocks and flows of metals in the anthroposphere. Over the past fifteen years, dynamic MFA has contributed to increased knowledge about the quantities, qualities, and locations of metal-containing goods. This article presents a literature review of the methodologies applied in 60 dynamic MFAs of metals. The review is based on a standardized model description format, the ODD (overview, design concepts, details) protocol. We focus on giving a comprehensive overview of modeling approaches and structure them according to essential aspects, such as their treatment of material dissipation, spatial dimension of flows, or data uncertainty. The reviewed literature features similar basic modeling principles but very diverse extrapolation methods. Basic principles include the calculation of outflows of the in-use stock based on inflow or stock data and a lifetime distribution function. For extrapolating stocks and flows, authors apply constant, linear, exponential, and logistic models or approaches based on socioeconomic variables, such as regression models or the intensity-of-use hypothesis. The consideration and treatment of further aspects, such as dissipation, spatial distribution, and data uncertainty, vary significantly and highly depends on the objectives of each study.

  9. Online traffic flow model applying dynamic flow-density relation

    International Nuclear Information System (INIS)

    Kim, Y.


    This dissertation describes a new approach of the online traffic flow modelling based on the hydrodynamic traffic flow model and an online process to adapt the flow-density relation dynamically. The new modelling approach was tested based on the real traffic situations in various homogeneous motorway sections and a motorway section with ramps and gave encouraging simulation results. This work is composed of two parts: first the analysis of traffic flow characteristics and second the development of a new online traffic flow model applying these characteristics. For homogeneous motorway sections traffic flow is classified into six different traffic states with different characteristics. Delimitation criteria were developed to separate these states. The hysteresis phenomena were analysed during the transitions between these traffic states. The traffic states and the transitions are represented on a states diagram with the flow axis and the density axis. For motorway sections with ramps the complicated traffic flow is simplified and classified into three traffic states depending on the propagation of congestion. The traffic states are represented on a phase diagram with the upstream demand axis and the interaction strength axis which was defined in this research. The states diagram and the phase diagram provide a basis for the development of the dynamic flow-density relation. The first-order hydrodynamic traffic flow model was programmed according to the cell-transmission scheme extended by the modification of flow dependent sending/receiving functions, the classification of cells and the determination strategy for the flow-density relation in the cells. The unreasonable results of macroscopic traffic flow models, which may occur in the first and last cells in certain conditions are alleviated by applying buffer cells between the traffic data and the model. The sending/receiving functions of the cells are determined dynamically based on the classification of the

  10. Low-flow-storage solar system for domestic hot water; Low-flow Speicherkonzept fuer die solare Trinkwassererwaermung

    Energy Technology Data Exchange (ETDEWEB)

    Leibfried, U. [CONSOLAR Energiespeicher- und Regelungssysteme GmbH, Frankfurt am Main (Germany)


    Solar domestic hot water treatment relies on effective and insulated reservoirs to maximize solar efficiency. The article describes a newly developed low flow stratification tank. Key feature of this system is the spiral flow of the coolant in countermovement to the drinking water being heated. (orig.) [German] Bei der Solaren Trinkwassererwaermung ist der Einsatz effektiver Speichersysteme notwendig, um den solaren Ertrag zu maximieren. Im Bericht wird ein low-flow Speicherkonzept vorgestellt. Bei diesem System stroemt der vom Solarkollektor kommende Waermetraeger spiralfoermig von oben nach unten im Gegenstrom zu sich erwaermenden Trinkwasser. (orig.)

  11. Cross-flow filtration and axial filtration

    International Nuclear Information System (INIS)

    Kraus, K.A.


    Two relatively novel alternative solid-liquid-separation techniques of filtration are discussed. In cross-flow filtration, the feed is pumped past the filtering surface. While in axial filtration the filter, mounted on a rotor, is moved with respect to the feed. While large-scale application of the axial filter is still in doubt, it permits with little expenditure of time and money, duplication of many hydrodynamic aspects of cross-flow filtration for fine-particle handling problems. The technique has been applied to municipal wastes, low-level radioactive waste treatment plant, lead removal from industrial wastes, removal of pulp-mill contaminants, textile-mill wastes, and pretreatment of saline waters by lime-soda process in preparation for hyperfiltration. Economics and energy requirements are also discussed

  12. Theoretical treatment of fluid flow for accelerating bodies

    CSIR Research Space (South Africa)

    Gledhill, Irvy MA


    Full Text Available Most computational fluid dynamics simulations are, at present, performed in a body-fixed frame, for aeronautical purposes. With the advent of sharp manoeuvre, which may lead to transient effects originating in the acceleration of the centre of mass...

  13. Arterial secondary blood flow patterns visualized with vector flow ultrasound

    DEFF Research Database (Denmark)

    Pedersen, Mads Møller; Pihl, Michael Johannes; Hansen, Jens Munk


    and velocity magnitudes the blood flow patterns were visualised with streamlines in Matlab (Mathworks, Natick, MA, USA). The rotational flow was quantified by the angular frequency for each cardiac cycle, and the mean rotational frequencies and standard deviations were calculated for the abdominal aorta f-1......This study presents the first quantification and visualisation of secondary flow patterns with vector flow ultrasound. The first commercial implementation of the vector flow method Transverse Oscillation was used to obtain in-vivo, 2D vector fields in real-time. The hypothesis of this study...... was that the rotational direction is constant within each artery. Three data sets of 10 seconds were obtained from three main arteries in healthy volunteers. For each data set the rotational flow patterns were identified during the diastole. Each data set contains a 2D vector field over time and with the vector angles...

  14. Radioisotopic flow scanning for portal blood flow and portal hypertension

    International Nuclear Information System (INIS)

    Hesdorffer, C.S.; Bezwoda, W.R.; Danilewitz, M.D.; Esser, J.D.; Tobias, M.


    The use of a simple, noninvasive, isotope scanning technique for the determination of relative portal blood flow and detection of portal hypertension is described. Using this technique the presence of portal hypertension was demonstrated in seven of nine patients known to have elevated portal venous pressure. By contrast, esophageal varices were demonstrated in only five of these patients, illustrating the potential value of the method. Furthermore, this technique has been adapted to the study of portal blood flow in patients with myeloproliferative disorders with splenomegaly but without disturbances in hepatic architecture. Results demonstrate that the high relative splenic flow resulting from the presence of splenomegaly may in turn be associated with elevated relative portal blood flow and portal hypertension. The theoretic reasons for the development of flow-related portal hypertension and its relationship to splenic blood flow are discussed

  15. Uso de modelação matemática para projeto de câmaras mecanizadas de floculação em série em estações de tratamento de água The use of mathematical modeling to the design of continous flow completely mixed chambers in series for flocculation in water treatment plants

    Directory of Open Access Journals (Sweden)

    Luiz Di Bernardo


    Full Text Available A metodologia encontrada na literatura para a otimização do gradiente de velocidade médio em reatores de mistura completa, com câmaras em série de escoamento contínuo, a partir de ensaios em reator estático tipo jarteste, baseia-se em modelos matemáticos que descrevem a cinética dos encontros entre partículas durante a floculação. Considerando-se que a aplicabilidade desta metodologia tem-se revelado inconsistente, como observado por diversos autores, este trabalho propõe uma metodologia racional para utilizar e otimizar os dados experimentais obtidos em reatores estáticos e, utilizando modelos matemáticos, obter dados para o projeto de floculadores mecanizados em série em estações de tratamento de água.The existing methodology in the literature to optimize the velocity gradients in continuous flow completely mixed reactors using batch test data (static reactors is based on mathematical models that describe the flocculation kinetics. Since this methodology has been shown to be inconsistent, as observed by several researchers, this work was carried out in order to propose a rational methodology to optimize the static reactors experimental data to obtain the design parameters of mechanized flocculation systems for water treatment plants.

  16. Integrated Lateral Flow Device for Flow Control with Blood Separation and Biosensing

    Directory of Open Access Journals (Sweden)

    Veronica Betancur


    Full Text Available Lateral flow devices are versatile and serve a wide variety of purposes, including medical, agricultural, environmental, and military applications. Yet, the most promising opportunities of these devices for diagnosis might reside in point-of-care (POC applications. Disposable paper-based lateral flow strips have been of particular interest, because they utilize low-cost materials and do not require expensive fabrication instruments. However, there are constraints on tuning flow rates and immunoassays functionalization in papers, as well as technical challenges in sensors’ integration and concentration units for low-abundant molecular detection. In the present work, we demonstrated an integrated lateral flow device that applied the capillary forces with functionalized polymer-based microfluidics as a strategy to realize a portable, simplified, and self-powered lateral flow device (LFD. The polydimethylsiloxane (PDMS surface was rendered hydrophilic via functionalization with different concentrations of Pluronic F127. Controlled flow is a key variable for immunoassay-based applications for providing enough time for protein binding to antibodies. The flow rate of the integrated LFD was regulated by the combination of multiple factors, including Pluronic F127 functionalized surface properties and surface treatments of microchannels, resistance of the integrated flow resistor, the dimensions of the microstructures and the spacing between them in the capillary pump, the contact angles, and viscosity of the fluids. Various plasma flow rates were regulated and achieved in the whole device. The LFD combined the ability to separate high quality plasma from human whole blood by using a highly asymmetric plasma separation membrane, and created controlled and steady fluid flow using capillary forces produced by the interfacial tensions. Biomarker immunoglobulin G (IgG detection from plasma was demonstrated with a graphene nanoelectronic sensor integrated

  17. Towards a universal description of cohesive-particle flows (United States)

    Lamarche, Casey; Liu, Peiyuan; Kellogg, Kevin; Lattanzi, Aaron; Hrenya, Christine


    A universal framework for describing cohesive granular flows seems unattainable based on prior works, making a fundamental continuum theory to predict such flows appear unachievable. For the first time, universal behavior of cohesive-grain flows is demonstrated by linking the macroscopic (many-grain) behavior to grain-grain interactions via two dimensionless groups: a generalized Bond number BoG - ratio of maximum cohesive force to the force driving flow - and a new Agglomerate number Ag - ratio of critical cohesive energy to the granular energy. Cohesive-grain flow is investigated in several systems, and universal behavior is determined via collapse of a cohesion-dependent output variable from each system with the appropriate dimensionless group. Universal behavior is observed using BoG for dense (enduring-contact-dominated) flows and Ag for dilute (collision-dominated) flows, as BoG accounts for the cohesive contact force and Ag for increased collisional dissipation due to cohesion. Hence, a new physical picture is presented, namely, BoG dominates in dense flows, where force chains drive momentum transfer, and Ag dominates in dilute systems, where the dissipative collisions dominate momentum transfer. Apparent discrepancies with past treatments are resolved. Dow Corning Corporation.

  18. Surface obstacles in pulsatile flow (United States)

    Carr, Ian A.; Plesniak, Michael W.


    Flows past obstacles mounted on flat surfaces have been widely studied due to their ubiquity in nature and engineering. For nearly all of these studies, the freestream flow over the obstacle was steady, i.e., constant velocity, unidirectional flow. Unsteady, pulsatile flows occur frequently in biology, geophysics, biomedical engineering, etc. Our study is aimed at extending the comprehensive knowledge base that exists for steady flows to considerably more complex pulsatile flows. Characterizing the vortex and wake dynamics of flows around surface obstacles embedded in pulsatile flows can provide insights into the underlying physics in all wake and junction flows. In this study, we experimentally investigate the wake of two canonical obstacles: a cube and a circular cylinder with an aspect ratio of unity. Our previous studies of a surface-mounted hemisphere in pulsatile flow are used as a baseline for these two new, more complex geometries. Phase-averaged PIV and hot-wire anemometry are used to characterize the dynamics of coherent structures in the wake and at the windward junction of the obstacles. Complex physics occur during the deceleration phase of the pulsatile inflow. We propose a framework for understanding these physics based on self-induced vortex propagation, similar to the phenomena exhibited by vortex rings.

  19. Flow instability in flow past O-grooved circular cylinder

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jaehee; Yang, Kyungsoo [Inha University, Inchun (Korea, Republic of)


    This study was devoted to elucidating the change in the flow characteristics of a laminar flow past a circular cylinder by modifying the cylinder shape with O-grooves. A numerical analysis was performed in a two-dimensional framework. The cylinder was represented using an immersed boundary method and marker particles on a Cartesian grid system. The number and locations of the O-grooves were the key parameters. An analysis of the flow pattern and flow induced forces was performed at Re = 40 and 50. In addition, we calculated the critical Reynolds number depending on the number of O-grooves and their locations.

  20. Dispersed flow film boiling

    International Nuclear Information System (INIS)

    Andreani, M.; Yadigaroglu, G.


    Dispersed flow film boiling is the heat transfer regime that occurs at high void fractions in a heated channel. The way this transfer mode is modelled in the NRC computer codes (RELAP5 and TRAC) and the validity of the assumption and empirical correlations used is discussed. An extensive review of the theoretical and experimental work related with heat transfer to highly dispersed mixtures reveals the basic deficiencies of these models: the investigation refers mostly to the typical conditions of low rate bottom reflooding, since the simulation of this physical situation by the computer codes has often showed poor results. The alternative models that are available in the literature are reviewed, and their merits and limits are highlighted. The modification that could improve the physics of the models implemented in the codes are identified. (author) 13 figs., 123 refs

  1. Lymphatic System Flows (United States)

    Moore, James E., Jr.; Bertram, Christopher D.


    The supply of oxygen and nutrients to tissues is performed by the blood system and involves a net leakage of fluid outward at the capillary level. One of the principal functions of the lymphatic system is to gather this fluid and return it to the blood system to maintain overall fluid balance. Fluid in the interstitial spaces is often at subatmospheric pressure, and the return points into the venous system are at pressures of approximately 20 cmH2O. This adverse pressure difference is overcome by the active pumping of collecting lymphatic vessels, which feature closely spaced one-way valves and contractile muscle cells in their walls. Passive vessel squeezing causes further pumping. The dynamics of lymphatic pumping have been investigated experimentally and mathematically, revealing complex behaviors that indicate that the system performance is robust against minor perturbations in pressure and flow. More serious disruptions can lead to incurable swelling of tissues called lymphedema.

  2. Transonic conical flow (United States)

    Agopian, K. G.


    The problem of inviscid, steady transonic conical flow, formulated in terms of the small disturbance theory, is studied. The small disturbance equation and similarity rules are presented, and a boundary value problem is formulated for the case of a supersonic freestream Mach number. The equation for the perturbation potential is solved numerically using an elliptic finite difference system. The difference equations are solved with a point relaxation algorithm that is also capable of capturing the shock wave during the iteration procedure by using the boundary conditions at the shock. Numerical calculations, for shock location, pressure distribution and drag coefficient, are presented for a family of nonlifting conical wings. The theory of slender wings is also presented and analytical results for pressure and drag coefficients are obtained.

  3. Flow Injection Analysis

    DEFF Research Database (Denmark)

    Hansen, Elo Harald


    This chapter provides an introduction to automated chemical analysis, which essentially can be divided into two groups: batch assays, where the solution is stationary while the container is moved through a number of stations where various unit operations performed; and continuous-flow procedures,......, but it permits thr execution of novel and unique analytical procedures which are difficult or even impossible by conventional means. The performance and applicability of FIA, SI and LOV are illustrated by a series of practical examples....... FIA is based on the creation of a concentration gradient of the injected sample solution and on reproducible and precise timing of all events, it allows exploitation of a transient read-out. This in turn implies that not only does FIA allow the augmentation of existing analytical techniques...

  4. Fuel cells flows study

    International Nuclear Information System (INIS)

    Riva, R.; Bador, B.; Marchand, M.; Lebaigue, O.


    Fuel cells are energy converters, which directly and continuously produce electricity from paired oxidation reduction-reactions: In most cases, the reactants are oxygen and hydrogen with water as residue. There are several types of fuel cells using various electrolytes and working at different temperatures. Proton Exchange Membrane Fuel Cells are, in particular, studied in the GESTEAU facility. PEMFC performance is chiefly limited by two thermal-hydraulic phenomena: the drying of membranes and the flooding of gas distributors. Up to now, work has been focused on water flooding of gas channels. This has showed the influence of flow type on the electrical behaviour of the cells and the results obtained have led to proposals for new duct geometries. (authors)

  5. Waves and compressible flow

    CERN Document Server

    Ockendon, Hilary


    Now in its second edition, this book continues to give readers a broad mathematical basis for modelling and understanding the wide range of wave phenomena encountered in modern applications.  New and expanded material includes topics such as elastoplastic waves and waves in plasmas, as well as new exercises.  Comprehensive collections of models are used to illustrate the underpinning mathematical methodologies, which include the basic ideas of the relevant partial differential equations, characteristics, ray theory, asymptotic analysis, dispersion, shock waves, and weak solutions. Although the main focus is on compressible fluid flow, the authors show how intimately gasdynamic waves are related to wave phenomena in many other areas of physical science.   Special emphasis is placed on the development of physical intuition to supplement and reinforce analytical thinking. Each chapter includes a complete set of carefully prepared exercises, making this a suitable textbook for students in applied mathematics, ...

  6. Lateral Flow Immunoassay. (United States)

    Ching, Kathryn H


    Lateral flow immunoassays (LFIAs) are a staple in the field of rapid diagnostics. These small handheld devices require no specialized training or equipment to operate, and generate a result within minutes of sample application. They are an ideal format for many types of home test kits, for emergency responders and for food manufacturers and producers looking for a quick evaluation of a given sample. LFIAs rely on high quality monoclonal antibodies that recognize the analyte of interest. As monoclonal antibody technology becomes more accessible to smaller laboratories, there has been increased interest in developing LFIA prototypes for potential commercial manufacture. In this chapter, the basics of designing and building an LFIA prototype are described.

  7. Wastewater treatment by flotation

    Directory of Open Access Journals (Sweden)

    F.P. Puget


    Full Text Available This work deals with the performance analysis of a separation set-up characterized by the ejector-hydrocyclone association, applied in the treatment of a synthetic dairy wastewater effluent. The results obtained were compared with the results from a flotation column (cylindrical body of a hydrocyclone operated both batch and continuously. As far as the experimental set-up studied in this work and the operating conditions imposed to the process, it is possible to reach a 25% decrease in the total effluent chemical oxygen demand (COD. This corresponds approximately to 60% of the COD of the material in suspension. The best results are obtained for ratios air flow rate-feed flow rate (Qair/Q L greater then 0.15 and for ratios underflow rate-overflow rate (Qu/Qo lower than 1.0.

  8. Uranyl Nitrate Flow Loop

    International Nuclear Information System (INIS)

    Ladd-Lively, Jennifer L


    The objectives of the work discussed in this report were to: (1) develop a flow loop that would simulate the purified uranium-bearing aqueous stream exiting the solvent extraction process in a natural uranium conversion plant (NUCP); (2) develop a test plan that would simulate normal operation and disturbances that could be anticipated in an NUCP; (3) use the flow loop to test commercially available flowmeters for use as safeguards monitors; and (4) recommend a flowmeter for production-scale testing at an NUCP. There has been interest in safeguarding conversion plants because the intermediate products [uranium dioxide (UO 2 ), uranium tetrafluoride (UF 4 ), and uranium hexafluoride (UF 6 )] are all suitable uranium feedstocks for producing special nuclear materials. Furthermore, if safeguards are not applied virtually any nuclear weapons program can obtain these feedstocks without detection by the International Atomic Energy Agency (IAEA). Historically, IAEA had not implemented safeguards until the purified UF 6 product was declared as feedstock for enrichment plants. H. A. Elayat et al. provide a basic definition of a safeguards system: 'The function of a safeguards system on a chemical conversion plant is in general terms to verify that no useful nuclear material is being diverted to use in a nuclear weapons program'. The IAEA now considers all highly purified uranium compounds as candidates for safeguarding. DOE is currently interested in 'developing instruments, tools, strategies, and methods that could be of use to the IAEA in the application of safeguards' for materials found in the front end of the nuclear fuel cycle-prior to the production of the uranium hexafluoride or oxides that have been the traditional starting point for IAEA safeguards. Several national laboratories, including Oak Ridge, Los Alamos, Lawrence Livermore, and Brookhaven, have been involved in developing tools or techniques for safeguarding conversion plants. This study was sponsored by

  9. Imposed Work of Breathing for Flow Meters with In-Line versus Flow-Through Technique during Simulated Neonatal Breathing.

    Directory of Open Access Journals (Sweden)

    Snorri Donaldsson

    Full Text Available The ability to determine airflow during nasal CPAP (NCPAP treatment without adding dead space or resistance would be useful when investigating the physiologic effects of different NCPAP systems on breathing. The aim of this study was to investigate the effect on pressure stability of different flow measuring devices at the in-line and flow-through position, using simulated neonatal breathing.Six different flow measure devices were evaluated by recording pressure changes and imposed work of breathing for breaths with 16 and 32 ml tidal volumes. The tests were performed initially with the devices in an in line position and with 5 and 10 L/min using flow through technique, without CPAP. The flow meters were then subsequently tested with an Infant Flow CPAP system at 3, 5 and 8 cm H2O pressure using flow through technique. The quality of the recorded signals was compared graphically.The resistance of the measuring devices generated pressure swings and imposed work of breathing. With bias flow, the resistance also generated CPAP pressure. Three of the devices had low resistance and generated no changes in pressure stability or CPAP pressure. The two devices intended for neonatal use had the highest measured resistance.The importance of pressure stability and increased work of breathing during non-invasive respiratory support are insufficiently studied. Clinical trials using flow-through technique have not focused on pressure stability. Our results indicate that a flow-through technique might be a way forward in obtaining a sufficiently high signal quality without the added effects of rebreathing and increased work of breathing. The results should stimulate further research and the development of equipment for dynamic flow measurements in neonates.

  10. Efficiency of osmotic pipe flows

    DEFF Research Database (Denmark)

    Haaning, Louise Sejling; Jensen, Kaare Hartvig; Helix Nielsen, Claus


    on the relative magnitude of radial diffusion and advection as well as the ratio of the osmotic velocity to pumping velocity, in very good agreement with experiments and with no adjustable parameters. Our analysis provides criteria that are useful for optimizing osmotic flow processes in, e.g., water purification......We present experiments and theory for flows of sugar or salt solutions in cylindrical tubes with semipermeable walls (hollow fiber membranes) immersed in water, quantifying the strength of the osmotic driving force in relation to the dimensionless parameters that specify the system. The pumping...... efficiency of these flows is limited by the presence of “unstirred” concentration boundary layers near the tube walls, and our primary aim is to understand and quantify these layers and their effect on the flow. We measure the outlet flow rate Qout while varying the inlet flow rate Q*, concentration c...

  11. Flow, affect and visual creativity. (United States)

    Cseh, Genevieve M; Phillips, Louise H; Pearson, David G


    Flow (being in the zone) is purported to have positive consequences in terms of affect and performance; however, there is no empirical evidence about these links in visual creativity. Positive affect often--but inconsistently--facilitates creativity, and both may be linked to experiencing flow. This study aimed to determine relationships between these variables within visual creativity. Participants performed the creative mental synthesis task to simulate the creative process. Affect change (pre- vs. post-task) and flow were measured via questionnaires. The creativity of synthesis drawings was rated objectively and subjectively by judges. Findings empirically demonstrate that flow is related to affect improvement during visual creativity. Affect change was linked to productivity and self-rated creativity, but no other objective or subjective performance measures. Flow was unrelated to all external performance measures but was highly correlated with self-rated creativity; flow may therefore motivate perseverance towards eventual excellence rather than provide direct cognitive enhancement.

  12. Active combustion flow modulation valve (United States)

    Hensel, John Peter; Black, Nathaniel; Thorton, Jimmy Dean; Vipperman, Jeffrey Stuart; Lambeth, David N; Clark, William W


    A flow modulation valve has a slidably translating hollow armature with at least one energizable coil wound around and fixably attached to the hollow armature. The energizable coil or coils are influenced by at least one permanent magnet surrounding the hollow armature and supported by an outer casing. Lorentz forces on the energizable coils which are translated to the hollow armature, increase or decrease the flow area to provide flow throttling action. The extent of hollow armature translation depends on the value of current supplied and the direction of translation depends on the direction of current flow. The compact nature of the flow modulation valve combined with the high forces afforded by the actuator design provide a flow modulation valve which is highly responsive to high-rate input control signals.

  13. Endovascular blood flow measurement system (United States)

    Khe, A. K.; Cherevko, A. A.; Chupakhin, A. P.; Krivoshapkin, A. L.; Orlov, K. Yu


    In this paper an endovascular measurement system used for intraoperative cerebral blood flow monitoring is described. The system is based on a Volcano ComboMap Pressure and Flow System extended with analogue-to-digital converter and PC laptop. A series of measurements performed in patients with cerebrovascular pathologies allows us to introduce “velocity-pressure” and “flow rate-energy flow rate” diagrams as important characteristics of the blood flow. The measurement system presented here can be used as an additional instrument in neurosurgery for assessment and monitoring of the operation procedure. Clinical data obtained with the system are used for construction of mathematical models and patient-specific simulations. The monitoring of the blood flow parameters during endovascular interventions was approved by the Ethics Committee at the Meshalkin Novosibirsk Research Institute of Circulation Pathology and included in certain surgical protocols for pre-, intra- and postoperative examinations.

  14. Corticosteroid Reduces Blood Flow to Femoral Heads in Rabbits. (United States)

    Hou, S.M.; Liu, T.K.; Kao, M.C.


    Avascular necrosis of the femoral head is one of the common problems in orthopedic practice in Taiwan. The subchondral bone loses its blood supply which weakens its biomechanical support. Steroid overuse is one of many possible etiologies in reducing blood flow to the femoral head. Laser Doppler velocimeter is a precise monitor of regional blood flow of bone which is expressed in perfusion units (PU). In the control group the rabbits were injected with normal saline and there were no statistical differences between blood flow to the right hip (39.26 +/- 5.64 PU) and left hip (38.58 +/- 4.35 PU). In group B a weekly injection of methylprednisolone into rabbits for 6 weeks demonstrated the reduction of blood flow of femoral head (24.74 +/- 3.13 PU) by the laser Doppler velocimeter. The flow decreased further (15.93 +/- 2.33 PU) by 12 weeks of steroid treatment. In group C after a weekly injection of steroid for 6 weeks the flow became 31.63 +/- 4.79 PU. The steroid was then discontinued for 3 weeks and the flow was 34.6 +/- 1.34 PU. In group D the blood flow was 25.89 +/- 4.01 PU after 6 weeks of steroid treatment and we stopped the steroid for 6 weeks, the blood flow became 29.86 +/- 2.59 PU. The merit of our experiment established a model of study in avascular necrosis of the femoral head in rabbits. Copyright 1994 S. Karger AG, Basel

  15. Characterization of Accelerating Pipe Flow. (United States)


    Journal of Chemical Engineering of Japan , vol...92, January 1970. 17. K. Kataoka, T. Kawabata, and K. Miki, "The Start-Up Response of Pipe Flow to a Step Change in Flow Rate," Journal of Chemical Engineering of Japan , vol...Pipe Flows," Journal of Chemical Engineering of Japan , vol. 9, no. 6, pp. 431-439, 1975. 19. E. van de Sande, A.P. Belde, B.J.G. Hamer, and W.

  16. High Speed Smoke Flow Visualization. (United States)


    releasable to the National Technical Information Service (NTIS). At NTIS, it will be available to the general public, including foreign nations. This... information . 9 The initial work focused on the evaluation of the flow field within the high speed flow visualization tunnels and the optical and...with the high speed flow visuLl iza tion; it waIs used to take simul taneous smoke/Schlieren photographs. Siice it allowed for this unique method of

  17. Identification of material flow systems. (United States)

    Bauer, G; Deistler, M; Gleiss, A; Glenck, E; Matyus, T


    Material Flow Analysis (MFA) has become an important instrument in environmental science and pollution research. In this paper, we look at the MFA problem as a particularly structured system identification problem. Special emphasis is given to the linear, static case, where we describe a procedure for reconciliating the flow measurements and for estimating the unmeasured flows and the transfer coefficients by taking into account a priori restrictions such as balance equations.

  18. Flow intake control using dry-weather forecast (United States)

    Icke, Otto; van Schagen, Kim; Huising, Christian; Wuister, Jasper; van Dijk, Edward; Budding, Arjan


    Level-based control of the influent flow causes peak discharges at a waste water treatment plant (WWTP) after rainfall events. Furthermore, the capacity of the post-treatment is in general smaller than the maximum hydraulic capacity of the WWTP. This results in a significant bypass of the post-treatment during peak discharge. The optimisation of influent flow reduces peak discharge, and increases the treatment efficiency of the whole water cycle, which benefits the surface water quality. In this paper, it is shown that half of the bypasses of the post-treatment can be prevented by predictive control. A predictive controller for influent flow is implemented using the Aquasuitetext">® Advanced Monitoring and Control platform. Based on real-time measured water levels in the sewerage and both rainfall and dry-weather flow (DWF) predictions, a discharge limitation is determined by a volume optimisation technique. For the analysed period (February-September 2016) results at WWTP Bennekom show that about 50 % of bypass volume can be prevented. Analysis of single rainfall events shows that the used approach is still conservative and that the bypass can be even further decreased by allowing discharge limitation during precipitation.

  19. Acceleration methods for multi-physics compressible flow (United States)

    Peles, Oren; Turkel, Eli


    In this work we investigate the Runge-Kutta (RK)/Implicit smoother scheme as a convergence accelerator for complex multi-physics flow problems including turbulent, reactive and also two-phase flows. The flows considered are subsonic, transonic and supersonic flows in complex geometries, and also can be either steady or unsteady flows. All of these problems are considered to be a very stiff. We then introduce an acceleration method for the compressible Navier-Stokes equations. We start with the multigrid method for pure subsonic flow, including reactive flows. We then add the Rossow-Swanson-Turkel RK/Implicit smoother that enables performing all these complex flow simulations with a reasonable CFL number. We next discuss the RK/Implicit smoother for time dependent problem and also for low Mach numbers. The preconditioner includes an intrinsic low Mach number treatment inside the smoother operator. We also develop a modified Roe scheme with a corresponding flux Jacobian matrix. We then give the extension of the method for real gas and reactive flow. Reactive flows are governed by a system of inhomogeneous Navier-Stokes equations with very stiff source terms. The extension of the RK/Implicit smoother requires an approximation of the source term Jacobian. The properties of the Jacobian are very important for the stability of the method. We discuss what the chemical physics theory of chemical kinetics tells about the mathematical properties of the Jacobian matrix. We focus on the implication of the Le-Chatelier's principle on the sign of the diagonal entries of the Jacobian. We present the implementation of the method for turbulent flow. We use a two RANS turbulent model - one equation model - Spalart-Allmaras and a two-equation model - k-ω SST model. The last extension is for two-phase flows with a gas as a main phase and Eulerian representation of a dispersed particles phase (EDP). We present some examples for such flow computations inside a ballistic evaluation

  20. A Marine Traffic Flow Model

    Directory of Open Access Journals (Sweden)

    Tsz Leung Yip


    Full Text Available A model is developed for studying marine traffic flow through classical traffic flow theories, which can provide us with a better understanding of the phenomenon of traffic flow of ships. On one hand, marine traffic has its special features and is fundamentally different from highway, air and pedestrian traffic. The existing traffic models cannot be simply extended to marine traffic without addressing marine traffic features. On the other hand, existing literature on marine traffic focuses on one ship or two ships but does not address the issues in marine traffic flow.