WorldWideScience

Sample records for adaptive bolus chasing

  1. Saving radiation dose and contrast media in intravenous digital subtraction angiography by use of bolus chasing

    Purpose: This study evaluates the dose area product, the amount of contrast media and the examination quality of the bolus chasing technique compared to the single-step technique in intravenous digital subtraction angiography. Material and Methods: 15 examinations each with bolus chasing and single-step technique were compared. The dose area product and the volume of contrast media were recorded. The examination quality was scored by two examiners. Results: With bolus chasing the volume of the administered contrast media could be decreased on average by 114 ml (43%). The difference between the dose area product of bolus chasing (722 dGy/cm2) and single-step technique (1910 dGy/cm2) was significant. No significant difference in examination quality was found. Conclusions: The intravenous bolus chasing technique is a practicable method. Compared to the single-step technique it allows a remarkable dose reduction and a low consumption of contrast media without restriction of examination quality. (orig.)

  2. The application of DSA bolus chase technology in diagnosing the vascular disorders of lower extremities due to diabetes mellitus

    Objective: To retrospectively evaluate the digital subtraction angiography (DSA) bolus chase technology in diagnosing the vascular disorders of lower extremities due to diabetes mellitus. Methods: From January 2004 to March 2010, DSA was performed in forty-five diabetes patients with suspicious vascular diseases of lower extremities. Among them, 24 cases (31 lower limbs)were examined with DSA bolus chase technology and the remaining 21 cases (21 lower limbs)were examined with traditional segmentational technique. The contrast dosage used in angiography, the total exposure time, the examination time and the imaging value for making diagnosis were analyzed and compared between two techniques. Results: For DSA bolus chase technology group, the contrast dosage used in angiography, the total exposure time and the examination time were 25.26 ml, 13.23 s and 37.26 min, respectively,with an average exposure of 101.65 pictures. For traditional segmentational technique group, the contrast dosage used in angiography, the total exposure time and the examination time were 130.00 ml, 52.38 s and 50.48 min, respectively, with an average exposure of 118.33 pictures. The percentage of high quality images in bolus chase technology group and in traditional segmentational technique group were 90.3% and 90.5%, respectively. All the images could meet the requirements for making a reliable diagnosis. Conclusion: Digital subtraction angiography by using bolus-chase technology can well demonstrate the vascular pathology of lower extremities caused by diabetes mellitus, obtain sufficient imaging information necessary for making a reliable diagnosis. DSA bolus chase technology is superior to traditional segmentational technique in shortening procedure time, reducing contrast medium dosage and decreasing radiation dose. (authors)

  3. Digital distal lower limb angiography: comparison of selective iliac injection with vasodilators and bolus chasing technique

    From October 1992 to May 1993 we carried out a prospective study on 30 patients, mean age 70 years, suffering from lower limb ischaemia (mild, n = 12; moderate, n = 9; severe, n = 9). Four masked investigators compared the outcome of two techniques for the preoperative evaluation of distal vessels of the lower limbs. The reference technique was digital subtraction angiography (DSA) with selective iliac injection, fixed centring on one ankle, and use of vasodilators. The new method was DSA with the so-called bolus chasing technique: after an injection above the aortic bifurcation, an acquisition during a continuous longitudinal translation movement allows all the arteries of the lower limbs to be visualised down to the most distal point. Both techniques are well tolerated and we found no significant difference in the number of distal arteries seen with the two methods. To assess the permeability of the distal lower limb network, the bolus tracking technique is as informative as an iliac selective injection, without its constraints. Consequently, we will routinely use it as the technique of choice. (orig.)

  4. Bolus characteristics based on Magnetic Resonance Angiography

    Bi Xiaoming

    2006-10-01

    Full Text Available Abstract Background A detailed contrast bolus propagation model is essential for optimizing bolus-chasing Computed Tomography Angiography (CTA. Bolus characteristics were studied using bolus-timing datasets from Magnetic Resonance Angiography (MRA for adaptive controller design and validation. Methods MRA bolus-timing datasets of the aorta in thirty patients were analyzed by a program developed with MATLAB. Bolus characteristics, such as peak position, dispersion and bolus velocity, were studied. The bolus profile was fit to a convolution function, which would serve as a mathematical model of bolus propagation in future controller design. Results The maximum speed of the bolus in the aorta ranged from 5–13 cm/s and the dwell time ranged from 7–13 seconds. Bolus characteristics were well described by the proposed propagation model, which included the exact functional relationships between the parameters and aortic location. Conclusion The convolution function describes bolus dynamics reasonably well and could be used to implement the adaptive controller design.

  5. Lockheed L-1011 TriStar to support Adaptive Performance Optimization study with NASA F-18 chase plan

    1995-01-01

    This Lockheed L-1011 Tristar, seen here June 1995, is currently the subject of a new flight research experiment developed by NASA's Dryden Flight Research Center, Edwards, California, to improve the effiecency of large transport aircraft. Shown with a NASA F-18 chase plane over California's Sierra Nevada mountains during an earlier baseline flight, the jetliner operated by Oribtal Sciences Corp., recently flew its first data-gathering mission in the Adaptive Performance Optimization project. The experiment seeks to reduce fuel comsumption of large jetliners by improving the aerodynamic efficiency of their wings at cruise conditions. A research computer employing a sophisticated software program adapts to changing flight conditions by commanding small movements of the L-1011's outboard ailerons to give its wings the most efficient - or optimal - airfoil. Up to a dozen research flights will be flown in the current and follow-on phases of the project over the next couple years.

  6. Chasing Noise

    Mendel, Brock; Shleifer, Andrei

    2012-01-01

    We present a simple model in which rational but uninformed traders occasionally chase noise as if it were information, thereby amplifying sentiment shocks and moving prices away from fundamental values. We fill a theoretical gap in the literature by showing conditions under which noise traders can have an impact on market equilibrium disproportionate to their size in the market. The model offers a partial explanation for the surprisingly low market price of financial risk in the Spring of 2007.

  7. Anatomy of the chase

    Grahne, Gosta; Onet, Adrian

    2013-01-01

    A lot of research activity has recently taken place around the chase procedure, due to its usefulness in data integration, data exchange, query optimization, peer data exchange and data correspondence, to mention a few. As the chase has been investigated and further developed by a number of research groups and authors, many variants of the chase have emerged and associated results obtained. Due to the heterogeneous nature of the area it is frequently difficult to verify the scope of each resu...

  8. Stop the Chase

    Meier, Michael; Schmidt, Michael; Lausen, Georg

    2009-01-01

    The chase procedure, an algorithm proposed 25+ years ago to fix constraint violations in database instances, has been successfully applied in a variety of contexts, such as query optimization, data exchange, and data integration. Its practicability, however, is limited by the fact that - for an arbitrary set of constraints - it might not terminate; even worse, chase termination is an undecidable problem in general. In response, the database community has proposed sufficient restrictions on to...

  9. Esophageal contractions, bolus transit and perception of transit after swallows of liquid and solid boluses in normal subjects

    Juciléia Dalmazo

    2012-12-01

    Full Text Available CONTEXT: Esophageal dysphagia is the sensation that the ingested material has a slow transit or blockage in its normal passage to the stomach. It is not always associated with motility or transit alterations. OBJECTIVES: To evaluate in normal volunteers the possibility of perception of bolus transit through the esophagus after swallows of liquid and solid boluses, the differences in esophageal contraction and transit with these boluses, and the association of transit perception with alteration of esophageal contraction and/or transit. METHODS: The investigation included 11 asymptomatic volunteers, 4 men and 7 women aged 19-58 years. The subjects were evaluated in the sitting position. They performed swallows of the same volume of liquid (isotonic drink and solid (macaroni boluses in a random order and in duplicate. After each swallow they were asked about the sensation of bolus passage through the esophagus. Contractions and transit were evaluated simultaneously by solid state manometry and impedance. RESULTS: Perception of bolus transit occurred only with the solid bolus. The amplitude and area under the curve of contractions were higher with swallows of the solid bolus than with swallows of the liquid bolus. The difference was more evident in swallows with no perception of transit (n = 12 than in swallows with perception (n = 10. The total bolus transit time was longer for the solid bolus than for the liquid bolus only with swallows followed by no perception of transit. CONCLUSION: The results suggest that the perception of esophageal transit may be the consequence of inadequate adaptation of esophageal transit and contraction to the characteristics of the swallowed bolus.

  10. Chase Lake Wetland Management District, Chase Lake National Wildlife Refuge, Chase Lake Prairie Project: Annual narrative report: 1997

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Chase Lake WMD, Chase Lake NWR, Chase Lake Prairie Project, and Halfway Lake NWR outlines Refuge accomplishments during the 1997...

  11. A Theory of Ambulance Chasing

    Backović, Mihailo

    2016-01-01

    Ambulance chasing is a common socio-scientific phenomenon in particle physics. I argue that despite the seeming complexity, it is possible to gain insight into both the qualitative and quantitative features of ambulance chasing dynamics. Compound-Poisson statistics suffices to accommodate the time evolution of the cumulative number of papers on a topic, where basic assumptions that the interest in the topic as well as the number of available ideas decrease with time appear to drive the time e...

  12. Evaluation of Pharyngeal Function between No Bolus and Bolus Propofol Induced Sedation for Advanced Upper Endoscopy

    Shinsuke Kiriyama; Hiroshi Naitoh; Minoru Fukuchi; Takaharu Fukasawa; Kana Saito; Yuichi Tabe; Hayato Yamauchi; Tomonori Yoshida; Hiroyuki Kuwano

    2014-01-01

    This study aimed to assess pharyngeal function between no bolus and bolus propofol induced sedation during gastric endoscopic submucosal dissection. A retrospective study was conducted involving consecutive gastric cancer patients. Patients in the no bolus group received a 3 mg/kg/h maintenance dose of propofol after the initiation of sedation without bolus injection. All patients in the bolus group received the same maintenance dose of propofol with bolus 0.5 mg/kg propofol injection. Pharyn...

  13. A Theory of Ambulance Chasing

    Backović, Mihailo

    2016-01-01

    Ambulance chasing is a common socio-scientific phenomenon in particle physics. I argue that despite the seeming complexity, it is possible to gain insight into both the qualitative and quantitative features of ambulance chasing dynamics. Compound-Poisson statistics suffices to accommodate the time evolution of the cumulative number of papers on a topic, where basic assumptions that the interest in the topic as well as the number of available ideas decrease with time appear to drive the time evolution. It follows that if the interest scales as an inverse power law in time, the cumulative number of papers on a topic is well described by a di-gamma function, with a distinct logarithmic behavior at large times. In cases where the interest decreases exponentially with time, the model predicts that the total number of papers on the topic will converge to a fixed value as time goes to infinity. I demonstrate that the two models are able to fit at least 9 specific instances of ambulance chasing in particle physics us...

  14. Chase Lake Wetland Management District, Chase Lake Prairie Project: Annual narrative report: Calendar year 1994

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Chase Lake WMD, Chase Lake Prairie Project, and Halfway Lake NWR outlines Refuge accomplishments during the 1994 calendar year. The...

  15. Chase Lake Wetland Management District, Chase Lake Prairie Project: Annual narrative report - 1993

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Chase Lake WMD, Chase Lake Prairie Project, and Halfway Lake NWR outlines Refuge accomplishments during the 1993 calendar year. The...

  16. Annual narrative report 1995: Chase Lake Wetland Management District, Chase Lake Prairie Project

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Chase Lake WMD, Chase Lake Prairie Project, and Halfway Lake NWR outlines Refuge accomplishments during the 1995 calendar year. The...

  17. Bolus propagation in pig ureter in vitro

    van Mastrigt, Ron; Tauecchio, E.A.

    1984-01-01

    textabstractPig ureters were made to propagate injected fluid boluses by electrical stimulation in vitro. The propagation velocity was determined from EMG measurements made at several points along the ureter. It was found that this velocity varied both along the ureter and as a function of time, and that it was related to the contraction pressure but not to the bolus size.

  18. Routing Discovery Algorithm Using Parallel Chase Packet

    Amera Al-Ameri

    2013-04-01

    Full Text Available On demand routing protocols for ad hoc networks such as Ad Hoc On Demand Distance Vector (AODV initiate a route discovery process when a route is needed by flooding the network with a route request packet. The route discovery process in such protocols depends on a simple flooding as a broadcast technique due to its simplicity. Simple flooding results in packet congestion, route request overhead and excessive collisions, namely broadcast storm problem. A number of routing techniques have been proposed to control the simple flooding technique. Ideally, the broadcast of route request or the route discovery process must be stopped as soon as the destination node is found. This will free the network from many redundant packets that may cause network collision and contention. In this paper, chasing packet technique is used with standard AODV routing protocol to end the fulfilled route requests. The chase packet is initiated by the source node and is broadcasted in parallel with route request packet. As soon as the destination is found the chase packet starts its work by trying to catch and discard the route request in early stages before it broadcasts further in the network. Performance evaluation is conducted using simulation to investigate the performance of the proposed scheme against the existing approach that uses chase packet technique such as Traffic Locality Route Discovery Algorithm with Chase (TLRDA-C. Results reveal that the proposed scheme minimizes end-to-end packet delays and achieves low routing request overhead.

  19. Accidental Bolus of Parenteral Nutrition.

    Lodeserto, Frank; Al-Jaghbeer, Mohammed; Huang, David

    2016-08-01

    There is a paucity of data that exists regarding acute toxicity and management in the setting of parental nutrition (PN) overdose. We describe a case of a patient who received an accidental rapid bolus of PN and fat emulsion. She developed a seizure, metabolic acidosis, arrhythmias, myocardial ischemia, altered mental status, hypotension, and hypoxemia likely caused by elevated triglycerides, leading to a hyperviscosity syndrome. After failing standard therapy, she was successfully treated with a single-volume plasma exchange with resolution of symptoms. Fat emulsion or intravenous lipid emulsion and much of its safety have been recently described in its use as a rescue therapy in resuscitation from drug-related toxicity. Elevated serum triglyceride levels can result in a picture similar to a hyperviscosity syndrome. Plasma exchange is a known therapeutic modality for the management of hyperviscosity syndrome and a novel therapy in the treatment of hyperviscosity syndrome due to fat emulsion therapy. In a patient receiving PN with development of rapid deterioration of clinical status, without an obvious etiology, there should be consideration of PN overdose. A rapid assessment and treatment of severe electrolyte abnormalities should be undertaken immediately to prevent life-threatening cardiovascular and central nervous system collapse. If fat emulsion was rapidly coadministered and there are signs and symptoms of hyperviscosity syndrome, then consideration should be given to plasma exchange as an effective therapeutic treatment option. PMID:25666023

  20. The data-exchange chase under the microscope

    Grahne, Gosta; Onet, Adrian

    2014-01-01

    In this paper we take closer look at recent developments for the chase procedure, and provide additional results. Our analysis allows us create a taxonomy of the chase variations and the properties they satisfy. Two of the most central problems regarding the chase is termination, and discovery of restricted classes of sets of dependencies that guarantee termination of the chase. The search for the restricted classes has been motivated by a fairly recent result that shows that it is undecidabl...

  1. 'Super Stuff' as bolus in radiotherapy

    The use of bolus materials for a tissue-equivalent field compensation is discussed and the application of compensation filters for high-energetic radiation is stressed. The properties of 'Super Stuff', which is colloidal, tissue-equivalent bolus, are described and compared with those of other materials such as polystyrene, plexiglas and water. The universal possibilities of applying 'Super Stuff' as field compensating material are demonstrated on a practical example in the field of the kV therapy. (orig.)

  2. Oesophageal food bolus impaction in elderly people

    Mitrović Slobodan M.

    2014-01-01

    Full Text Available Introduction. The diagnosis of food bolus impaction in the esophagus is based on the data obtained from the patient, clinical examination, radiographic diagnosis, and endoscopy. The aim of this study was to examine the influence of possible factors causing oesophageal impaction of food boluses in elderly people. Material and Methods. This retrospective study included six male and eight female patients treated at the Department of Ear, Nose, and Throat Disease in Novi Sad. Results. Post-corrosive oesophageal stricture was diagnosed in 28.57% of patients and non-corrosive stricture was found in 21.43%. Total tooth loss was recorded in 64.29% of patients and 14.29% of patients had partial tooth loss. An impacted food bolus was located at a distance of 15-25 cm or 30-40 cm distance from the upper incisors in 42.86% of the study sample. Discussion and conclusion. The impaction of food boluses in the esophagus is significantly higher in women, usually after 76 years of age. There is a positive correlation between the presence of oesophageal stricture and recurrence of food bolus impaction. Partial and total tooth loss is present in a high percentage but there is no correlation with the food bolus impaction. Impaction of food bolus was equally found in the upper and lower third of the oesophagus and it was usually meat. Radiographic diagnosis should precede each esophagoscopy. Esophagoscopy with rigid oesophagoscope is a reliable method for the extraction of a bolus of food from the oesophagus in elderly patients.

  3. Comprehensive MR angiography of the lower limbs: a hybrid dual-bolus approach including the pedal arteries

    Schmitt, R.; Coblenz, G.; Cherevatyy, O.; Brunner, H.; Froehner, S.; Wedell, E.; Christopoulos, G. [Herz- und Gefaessklinik GmbH, Diagnostic and Interventional Radiology, Bad Neustadt an der Saale (Germany); Karg, G. [Siemens Medical Solutions, Erlangen (Germany)

    2005-12-01

    The purpose of this study was to include the pedal vasculature into the coverage of peripheral multistation magnetic resonance angiography (3DceMRA). A total of 216 patients suffering from peripheral vascular disease were examined with a modified hybrid dual-bolus technique. The cruropedal arteries were acquired first with two sagittal slabs and time-resolved 3D sequences. Then the aortofemoral vessels were visualized using the bolus-chase technique and a second contrast injection. Interventional procedures were performed in 104 patients, and in 69 of those, the cruropedal vessels were also examined with digital subtraction angiography (iaDSA). Using 3DceMRA, the cruropedal arteries were displayed with both excellent and good quality in 95% (205/216 cases), and without any venous overlay in 94% (203/216 cases). The aortofemoral vessels were not jeopardized by the first contrast injection. With iaDSA as the standard of reference, observed sensitivity of 3DceMRA was found in ranges from 80% (29%, 99%) to 100% (86%, 100%) for assessing significant stenoses, and observed specificity ranged between 93% [80%, 98%] and 100% (82%, 100%). In conclusion, hybrid dual-bolus 3DceMRA significantly reduces the limitations of standard single-bolus 3DceMRA in anatomic coverage and temporal resolution of the cruropedal arteries, thus providing high-quality images of the entire peripheral vasculature. (orig.)

  4. Chinese Learning Journeys: Chasing the Dream

    Su, Feng, Ed.

    2011-01-01

    Eight students from mainland China chart their learning journeys across national and continental boundaries and socio-cultural contexts. The five women and three men structure their experiences of studying in China and the West around the turning points and life changing choices they made in chasing their dreams. They embody its emergent…

  5. Chases and Bag-Set Certain Answers

    Thorne, Camilo

    2014-01-01

    In this paper we show that the chase technique is powerful enough to capture the bag-set semantics of conjunctive queries over IDBs and IDs and TGDs. In addition, we argue that in such cases it provides efficient (LogSpace) query evaluation algorithms and that, moreover, it can serve as a basis for evaluating some restricted classes of aggregate queries under incomplete information.

  6. Taming the Infinite Chase: Query Answering under Expressive Integrity Constraints

    Cali, Andrea; Gottlob, Georg; Kifer, Michael

    2012-01-01

    The chase algorithm is a fundamental tool for query evaluation and query containment under constraints, where the constraints are (sub-classes of) tuple-generating dependencies (TGDs) and equality generating depencies (EGDs). So far, most of the research on this topic has focused on cases where the chase procedure terminates, with some notable exceptions. In this paper we take a general approach, and we propose large classes of TGDs under which the chase does not always terminate. Our languag...

  7. 21 CFR 520.2345c - Tetracycline boluses.

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Tetracycline boluses. 520.2345c Section 520.2345c... DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2345c Tetracycline boluses. (a) Specifications. Each bolus contains 500 milligrams of tetracycline (as the hydrochloride)....

  8. The comparison of imaging quality between bolus-triggering and test-bolus technique used in 64-slice spiral CT angiography of lower extremity arteries

    .01). Conclusion: There was a wide interindividual variation in transit time for contrast medium to reach aorta and politeal artery. Adaptive method by using two low-dose test bolus injection determined interindividual variation in delay time and scan time and thus above parameters was able to produce better quality images than using bolus triggering technique in below knee and foot region arteries. (authors)

  9. eCHASE: Exploiting Cultural Heritage using the Semantic Web

    Sinclair, Patrick; Lewis, Paul; Martinez, Kirk; Addis, Matthew; Pillinger, Adrian; Prideaux, Daniel

    2005-01-01

    The eCHASE project is using semantic web technologies to demonstrate sustainable business models based on access and exploitation of digital cultural heritage content at a European level. In this paper we describe the eCHASE project and outline the system architecture.

  10. Paper Chase and the Socratic Method of Teaching Law.

    Dillon, J. T.

    1980-01-01

    It is argued that the Socratic method of teaching law as depicted in the book, movie, and TV series "Paper Chase" is not really the Socratic method at all. The genuine Socratic method and the questioning technique used in "Paper Chase" are examined and their appropriateness and effectiveness as methods for teaching contract law are questioned.…

  11. A study on developing customized bolus using 3D prints

    Jung, Sang Min; Yang, Jin Ho; Lee, Seung Hyun; Kim, Jin Uk; Yeom, Du Seok [Dept. of Proton Therapy Center, National Cancer Center, Ilsan (Korea, Republic of)

    2015-06-15

    3D Printers are used to create three-dimensional models based on blueprints. Based on this characteristic, it is feasible to develop a bolus that can minimize the air gap between skin and bolus in radiotherapy. This study aims to compare and analyze air gap and target dose at the branded 1 cm bolus with the developed customized bolus using 3D printers. RANDO phantom with a protruded tumor was used to procure images using CT simulator. CT DICOM file was transferred into the STL file, equivalent to 3D printers. Using this, customized bolus molding box (maintaining the 1 cm width) was created by processing 3D printers, and paraffin was melted to develop the customized bolus. The air gap of customized bolus and the branded 1 cm bolus was checked, and the differences in air gap was used to compare D{sub max}, D{sub min}, D{sub mean}, D{sub 95%} and V{sub 95%} in treatment plan through Eclipse. Customized bolus production period took about 3 days. The total volume of air gap was average 3.9 cm{sup 3} at the customized bolus. And it was average 29.6cm{sup 3} at the branded 1 cm bolus. The customized bolus developed by the 3D printer was more useful in minimizing the air gap than the branded 1 cm bolus. In the 6 MV photon, at the customized bolus, D{sub max}, D{sub min}, D{sub mean}, D{sub 95%}, V{sub 95%} of GTV were 102.8%, 88.1%, 99.1%, 95.0%, 94.4% and the D{sub max}, D{sub min}, D{sub mean}, D{sub 95%}, V{sub 95%} of branded 1 cm bolus were 101.4%, 92.0%, 98.2%, 95.2%, 95.7%, respectively. In the proton, at the customized bolus, D{sub max}, D{sub min}, D{sub mean}, D{sub 95%}, V{sub 95%} of GTV were 104.1%, 84.0%, 101.2%, 95.1%, 99.8% and the D{sub max}, D{sub min}, D{sub mean}, D{sub 95%}, V{sub 95%} of branded 1cm bolus were 104.8%, 87.9%, 101.5%, 94.9%, 99.9%, respectively. Thus, in treatment plan, there was no significant difference between the customized bolus and 1 cm bolus. However, the normal tissue nearby the GTV showed relatively lower radiation dose. The

  12. Degradation Parameters from Pulse-Chase Experiments

    Sin, Celine; Chiarugi, Davide; Valleriani, Angelo

    2016-01-01

    Pulse-chase experiments are often used to study the degradation of macromolecules such as proteins or mRNA. Considerations for the choice of pulse length include the toxicity of the pulse to the cell and maximization of labeling. In the general case of non-exponential decay, varying the length of the pulse results in decay patterns that look different. Analysis of these patterns without consideration to pulse length would yield incorrect degradation parameters. Here we propose a method that constructively includes pulse length in the analysis of decay patterns and extracts the parameters of the underlying degradation process. We also show how to extract decay parameters reliably from measurements taken during the pulse phase. PMID:27182698

  13. Optical tracking of contrast medium bolus to optimize bolus shape and timing in dynamic computed tomography

    Eisa, Fabian; Brauweiler, Robert; Peetz, Alexander; Hupfer, Martin; Nowak, Tristan; Kalender, Willi A.

    2012-05-01

    One of the biggest challenges in dynamic contrast-enhanced CT is the optimal synchronization of scan start and duration with contrast medium administration in order to optimize image contrast and to reduce the amount of contrast medium. We present a new optically based approach, which was developed to investigate and optimize bolus timing and shape. The time-concentration curve of an intravenously injected test bolus of a dye is measured in peripheral vessels with an optical sensor prior to the diagnostic CT scan. The curves can be used to assess bolus shapes as a function of injection protocols and to determine contrast medium arrival times. Preliminary results for phantom and animal experiments showed the expected linear behavior between dye concentration and absorption. The kinetics of the dye was compared to iodinated contrast medium and was found to be in good agreement. The contrast enhancement curves were reliably detected in three mice with individual bolus shapes and delay times of 2.1, 3.5 and 6.1 s, respectively. The optical sensor appears to be a promising approach to optimize injection protocols and contrast enhancement timing and is applicable to all modalities without implying any additional radiation dose. Clinical tests are still necessary.

  14. Knowing When to Stop: The Brain Mechanisms of Chasing Losses

    Campbell-Meiklejohn, Daniel; Woolrich, Mark; Passingham, Dick;

    2008-01-01

    adult participants decided to chase losses or decided to quit gambling to prevent further losses.ResultsChasing losses was associated with increased activity in cortical areas linked to incentive-motivation and an expectation of reward. By contrast, quitting was associated with decreased activity in......-chasing behavior in pathological gambling might involve a failure to appropriately balance activity within neural systems coding conflicting motivational states. Similar mechanisms might underlie the loss-of-control over appetitive behaviors in other impulse control disorders....

  15. Chases and escapes the mathematics of pursuit and evasion

    Nahin, Paul J

    2012-01-01

    We all played tag when we were kids. What most of us don't realize is that this simple chase game is in fact an application of pursuit theory, and that the same principles of games like tag, dodgeball, and hide-and-seek are also at play in military strategy, high-seas chases by the Coast Guard, and even romantic pursuits. In Chases and Escapes, Paul Nahin gives us the first complete history of this fascinating area of mathematics, from its classical analytical beginnings to the present day. Drawing on game theory, geometry, linear algebra, target-tracking algorithms, and much

  16. Panicum sect. Dichotomiflora (Hitchc. & Chase) Honda e P. sect. Virgata Hitchc. & Chase ex Pilg. (Poaceae: Panicoideae: Paniceae) no Brasil Panicum sect. Dichotomiflora (Hitchc. & Chase) Honda and P. sect. Virgata Hitchc. & Chase ex Pilg. (Poaceae: Panicoideae: Paniceae) in Brazil

    Adriana Guglieri; Hilda Maria Longhi-Wagner; Fernando O Zuloaga

    2007-01-01

    (Panicum sect. Dichotomiflora (Hitchc. & Chase) Honda e P. sect. Virgata Hitchc. & Chase ex Pilg. (Poaceae: Panicoideae: Paniceae) no Brasil). Panicum L. subg. Panicum inclui cerca de 100 espécies predominantemente tropicais. Deste total, aproximadamente 50 espécies são americanas e ocorrem desde o Canadá até Argentina, Uruguai e Brasil. Está representado no Brasil por 30 espécies, três delas sem seção definida, e as demais distribuídas entre P. sect. Dichotomiflora (Hitchc. & Chase) Honda, P...

  17. Bolus materials mainly made of chewing gum base

    The authors preliminarily report useful bolus materials for therapy with high energy electrons and photons. The substances are made of mainly chewing gum base (CGB), and have thermoplasticity around 400C. Two bolus materials (CGB-3 and -4) are available, and these radiological properties are as follows (1) effective atomic number -7.51 for both, (2) electron density relative to water -1.05 for CGB-3, 1.00 for CGB-4. The basic studies, process to make bolus, clinical uses and indications are described. The characteristics of these bolus materials in radiotherapy planning with CT scanner and in high energy electron beam therapy are discussed. (author)

  18. ECMO: Improving our Results by Chasing the Rabbits

    Luiz Fernando Canêo

    2015-12-01

    Full Text Available ABSTRACT As Marcelo Giugale published in the Financial Times, Latin America, on the whole, has not excelled at innovation - doing the same things in a new and better way or at doing new things. It has been slow to acquire, adopt and adapt technologies by this time available in other places[1]. Although extracorporeal membrane oxygenation (ECMO is not a new technology, its use in Latin America is not widespread as needed. Furthermore, we still have a number centers doing ECMO, not reporting their cases, lacking a structured training program and not registered with the extracorporeal life support organization (ELSO. With this scenario, and accepting that ECMO is the first step in any circulatory support program, it is difficult to anticipate the incorporation of new and more complex devices as the technologically advanced world is currently doing. However, the good news is that with the support of experts from USA, Europe and Canada the results in Latin America ELSO'S centers are improving by following its guidelines for training, and using a standard educational process. There is no doubt that we can learn a great deal from the high velocity organizations - the rabbits - whom everyone chases but never catches, that manage to stay ahead because of their endurance, responsiveness, and their velocity in self-correction[2].

  19. ECMO: Improving our Results by Chasing the Rabbits.

    Canêo, Luiz Fernando; Neirotti, Rodolfo A

    2015-12-01

    As Marcelo Giugale published in the Financial Times, Latin America, on the whole, has not excelled at innovation - doing the same things in a new and better way or at doing new things. It has been slow to acquire, adopt and adapt technologies by this time available in other places[1]. Although extracorporeal membrane oxygenation (ECMO) is not a new technology, its use in Latin America is not widespread as needed. Furthermore, we still have a number centers doing ECMO, not reporting their cases, lacking a structured training program and not registered with the extracorporeal life support organization (ELSO). With this scenario, and accepting that ECMO is the first step in any circulatory support program, it is difficult to anticipate the incorporation of new and more complex devices as the technologically advanced world is currently doing. However, the good news is that with the support of experts from USA, Europe and Canada the results in Latin America ELSO'S centers are improving by following its guidelines for training, and using a standard educational process. There is no doubt that we can learn a great deal from the high velocity organizations - the rabbits - whom everyone chases but never catches, that manage to stay ahead because of their endurance, responsiveness, and their velocity in self-correction[2]. PMID:26934407

  20. Esophageal contractions, bolus transit and perception of transit after swallows of liquid and solid boluses in normal subjects

    Juciléia Dalmazo; Lilian Rose Otoboni Aprile; Roberto Oliveira Dantas

    2012-01-01

    CONTEXT: Esophageal dysphagia is the sensation that the ingested material has a slow transit or blockage in its normal passage to the stomach. It is not always associated with motility or transit alterations. OBJECTIVES: To evaluate in normal volunteers the possibility of perception of bolus transit through the esophagus after swallows of liquid and solid boluses, the differences in esophageal contraction and transit with these boluses, and the association of transit perception with alteratio...

  1. Chase Lake National Wildlife Refuge [Land Status Map

    US Fish and Wildlife Service, Department of the Interior — This map was produced by the Division of Realty to depict landownership at Chase Lake National Wildlife Refuge. It was generated from rectified aerial photography,...

  2. Episodic chasing in pathological gamblers using the Iowa gambling task

    Linnet, J.; Rojskjaer, S.; Nygaard, Jørgen;

    2006-01-01

    "Chasing ones losses" is a key symptom among pathological gamblers (PGs). This study focuses on quantitative differences in episodic chasing (i.e., sequences of disadvantageous decisions within a single gambling session) between PGs and non-pathological gamblers (NPGs). We compared 61 PGs and 39...... NPGs on the Iowa Gambling Task (IGT) and the Zuckerman Sensation Seeking Scale (SSS). The PGs showed significantly more chasing and had significantly poorer decision-making strategies than NPGs, particularly among males (F = 4.52, p <0.05). Random players were significantly less sensation seeking than...... advantageous and disadvantageous (i.e., chasing) players, but there was no interaction with group or gender. The results suggest that quantifiable within-session gambling behavior holds important implications for detecting underlying vulnerabilities to gambling pathology....

  3. SWFSC/MMTD/ETP: Chase Encirclement Stress Studies (CHESS) 2001

    National Oceanic and Atmospheric Administration, Department of Commerce — The CHase Encirclement Stress Studies (CHESS) are part of a comprehensive research program designed to investigate the status of dolphin stocks that are involved in...

  4. Converging to the Chase - a Tool for Finite Controllability

    Gogacz, T.; Marcinkowski, J.

    2012-01-01

    We solve a problem, stated in [CGP10], showing that Sticky Datalog, defined in the cited paper as an element of the Datalog\\pm project, has the finite controllability property. In order to do that, we develop a technique, which we believe can have further applications, of approximating Chase(D, T), for a database instance D and some sets of tuple generating dependencies T, by an infinite sequence of finite structures, all of them being models of T.

  5. Chip-Level HARQ Chase Combining for HSUPA

    Et Tolba, Mohamed; Saoudi, Samir; Visoz, Raphaël; Ait-Idir, Tarik

    2009-01-01

    Hybrid automatic repeat request (HARQ) is used in high-speed uplink packet access (HSUPA) to increase the data rate. Chase combining is the simplest of HARQ algorithms. It provides a time diversity and requires a small memory. In this paper, we propose a technique to increase the chase combining efficiency. In this method, HARQ transmissions are seen as additional receive antennas which are jointly combined at chip-level using a space-time linear minimum square error (LMMSE). We demonstrate t...

  6. Analysis of bolus formation in micropipette ejection systems.

    Mirbod, Parisa; Meng, Diwen

    2015-06-01

    The ejection of drugs from micropipettes is practiced frequently in biomedical research and clinical studies however, little is known about the dynamics of this process. The fundamentals of disperse fluid injection via a capillary into an ambient immiscible fluid have been investigated extensively. Here, we experimentally investigate the bolus formation in micropipette ejection systems, where the injection and ambient fluid are the same. We experimentally measure the temporal evolution of the bolus formation in the same fluid. There are three different bolus formation mechanisms that arise from different Re t regimes: a) a nearly spherical bolus, b) a pear-like bolus, and c) a large distortion or axial jet. We examine the scaled dimensions of the bolus, R b/D t, L b/D t, H/D t, and α, as a function of the dimensionless parameters such as tip Reynolds number, Re t, dimensionless value of g/(D t (.) V t), the dimensionless time, tV t/D t, and the distance between the edge of the micropipette and the free surface, D/D t. The bolus radius for 0.2 < Re t < 30 grows according to t (1/2) in the entire time range, which allows us to estimate the time for complete bolus formation. PMID:26100535

  7. Infants' preference for individual agents within chasing interactions.

    Galazka, Martyna; Nyström, Pär

    2016-07-01

    Infants, like adults, are able to discriminate between chasing and non-chasing interactions when watching animations with simple geometric shapes. But where infants derive the necessary information for discrimination and how chasing detection influences later visual attention has been previously unexplored. Here, using eye tracking, we investigated how 5- and 12-month-old infants (N=94) distribute their visual attention among individual members within different interactions depending on a type of interaction. Infant gaze was examined when observing animations depicting chasing and following interactions compared with animations displaying randomly moving shapes. Results demonstrate that when observing chasing and following interactions, all infants strongly preferred to attend to the agent that initiates an interaction and trails behind another. Low-level features, such as changes in agent-specific velocity profiles, could not account for this preference (Study 2). Rather, the strong preference for the agent going behind seems to be dependent on the initial goal-directed or "heat-seeking" motion of one agent toward another (Study 3). The current set of experiments suggests that, similar to adults, 5-months-olds' visual attention depends on the motion features of an individual agent within the interaction and is fine-tuned to agents that display goal-directed motion toward other agents. PMID:27017143

  8. The CHASE laboratory search for chameleon dark energy

    Steffen, Jason H.; /Fermilab

    2010-11-01

    A scalar field is a favorite candidate for the particle responsible for dark energy. However, few theoretical means exist that can simultaneously explain the observed acceleration of the Universe and evade tests of gravity. The chameleon mechanism, whereby the properties of a particle depend upon the local environment, is one possible avenue. We present the results of the Chameleon Afterglow Search (CHASE) experiment, a laboratory probe for chameleon dark energy. CHASE marks a significant improvement other searches for chameleons both in terms of its sensitivity to the photon/chameleon coupling as well as its sensitivity to the classes of chameleon dark energy models and standard power-law models. Since chameleon dark energy is virtually indistinguishable from a cosmological constant, CHASE tests dark energy models in a manner not accessible to astronomical surveys.

  9. The CHASE laboratory search for chameleon dark energy

    Steffen, Jason [Fermi National Accelerator Laboratory - Fermilab, P.O. Box 500, Batavia, IL 60510-5011 (United States)

    2010-07-01

    A scalar field is a favorite candidate for the particle responsible for dark energy. However, few theoretical means exist that can simultaneously explain the observed acceleration of the Universe and evade tests of gravity. The chameleon mechanism, whereby the properties of a particle depend upon the local environment, is one possible avenue. I present the results of the Chameleon Afterglow Search (CHASE) experiment, a laboratory probe for chameleon dark energy. CHASE marks a significant improvement over other searches for chameleons both in terms of its sensitivity to the photon/chameleon coupling as well as its sensitivity to the classes of chameleon dark energy models and standard power-law models. Since chameleon dark energy is virtually indistinguishable from a cosmological constant, CHASE tests dark energy models in a manner not accessible to astronomical surveys. (author)

  10. The CHASE laboratory search for chameleon dark energy

    A scalar field is a favorite candidate for the particle responsible for dark energy. However, few theoretical means exist that can simultaneously explain the observed acceleration of the Universe and evade tests of gravity. The chameleon mechanism, whereby the properties of a particle depend upon the local environment, is one possible avenue. We present the results of the Chameleon Afterglow Search (CHASE) experiment, a laboratory probe for chameleon dark energy. CHASE marks a significant improvement other searches for chameleons both in terms of its sensitivity to the photon/chameleon coupling as well as its sensitivity to the classes of chameleon dark energy models and standard power-law models. Since chameleon dark energy is virtually indistinguishable from a cosmological constant, CHASE tests dark energy models in a manner not accessible to astronomical surveys.

  11. Chase Lake Prairie Project/WMD: Annual narrative report: Calendar year 1996

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Chase Lake WMD, Chase Lake Prairie Project, and Halfway Lake NWR outlines Refuge accomplishments during the 1996 calendar year. The...

  12. Cooperative and Human Aspects of Software Engineering (CHASE 2008)

    2008-01-01

    The CHASE 2008 workshop is concerned with exploring the cooperative and human aspects of software engineering, and providing a forum for discussing high-quality research. Accepted papers reflect diversity of the field of software engineering – ranging from requirements to testing, and from...... ethnographic research to experiments. Moreover, the background of attendees reflects the diversity of researchers in this domain, ranging from sociology to psychology, from informatics to software engineering. CHASE 1008 met its goals in presenting high-quality research and building community through a mixture...... of presentations, discussions, posters, and social activities....

  13. A Performance Analysis of Chasing Intruders by Implementing Mobile Agents

    Omid Mahdi Ebadati E.

    2010-10-01

    Full Text Available An Intrusion Detection System in network fetches the intrusions information from systems by using Mobile Agents aid. Intrusion Detection System detects intrusions based on the collected information and routes the intrusion. The intelligent decisions on communications, permit agents to gain their goals more efficiently and provide more survivability and security of an agent system. The proposed model showed a formal representation of information assurance in agent messaging over a dynamic network by probability of redundant routes. The proposed Intrusion Detection System, chase intruders and collect information by the Mobile Agents. Our propose architecture is an information exchange method and chasing intrusion along with a method by implementing Mobile Agents.

  14. Methods of bolusing the tracheostomy stoma

    Purpose: The tracheostomy stoma is a potential site of recurrence for patients who have subglottic cancer or subglottic spread of cancer. In these patients, it is important that the anterior supraclavicular field does not underdose the posterior wall of the tracheostomy stoma when using a 6-MV anterior photon field. Conventionally, this problem is surmounted with placement of a plastic tracheostomy tube, which is uncomfortable for the patient, potentially traumatic, and can interfere with vocalization via a tracheal esophageal puncture. Our study was designed to investigate the dosimetry of this region and see if alternate methods would be effective. Methods and Materials: A phantom was constructed using a No. 6 tracheostomy tube as the model for the tracheostomy curvature and size. Using the water-equivalent phantom, film dosimetry, and films oriented parallel to the en face field, we investigated the dose at the depth of the surface of the posterior wall of the phantom's tracheostomy stoma. Dose was measured both in space and at the tissue interface by scanning points of interest both horizontally and vertically. We measured doses with a No. 6 and No. 8 plastic tracheostomy tube, either 0.5 cm and 1.0 cm of bolus (1-cm airhole) with no tracheostomy tube, as well as 0.3 cm and 0.6 cm tissue-equivalent Aquaplast (Med-Tec Co., Orange City, Iowa) over the tracheostomy. Dosimetry at the posterior interface was confirmed using thermoluminescent dosimeters. Results: Three mm and 6 mm of Aquaplast produced a posterior tracheal dose of 93% and 100%. Conclusion: There is no need for these patients to wear a temporary plastic tracheostomy tube during their external radiation therapy. Aquaplast should allow better position reproducibility, reduce trauma, not interfere with patient respiratory efforts, and be compatible with vocalization via a tracheal esophageal puncture

  15. Micropropagation of Gerbera (Gerbera jamesonii Bolus).

    Minerva, Ghani; Kumar, Surinder

    2013-01-01

    Gerbera (Gerbera jamesonii Bolus) is one of the most popular ornamental flowers worldwide and used both as cut flower and potted plant. Some of them show excellent agronomic characters such as color, floral diameter, stem length, and vigor, which make this plant of commercial importance. Conventionally, multiplication is done through seeds or rhizome cuttings. Rapid multiplication of elite cultivars of Gerbera, with improved agronomic traits, has been achieved by using both direct and indirect tissue culture methods. Direct shoot regeneration was accomplished from stem apices on MS medium supplemented with 1 mg/L 6-benzyladenine (BA) and 1 mg/L kinetin. Indirect shoot induction succeeded from callus differentiation has been achieved on MS medium containing 2 mg/L 2,4-dichlorophenoxyacetic acid, 0.5 mg/L indole-3-acetic acid, and 2 mg/L BA. The in vitro shoots, 4-5 cm long, were rooted by quick dipping the shoot bases for 3-5 s in 2,000 mg/L indole-3-butyric acid solution followed by transfer to the pots containing farmyard manure, soil, and sand (1:1:1 by volume). Initially, in vitro plantlets were covered with glass jars to maintain a high relative humidity (85-90%). As soon as new shoot growth begins, relative humidity is decreased by exposing them to the open environmental conditions prior transferring to the glasshouse. Indirect shoot regeneration increased the frequency of somaclonal variations. The selected somaclones were used in developing new and novel cultivars. PMID:23179709

  16. Episodic chasing in pathological gamblers using the Iowa gambling task

    Linnet, J.; Rojskjaer, S.; Nygaard, Jørgen; Maher, B.A.

    2006-01-01

    NPGs on the Iowa Gambling Task (IGT) and the Zuckerman Sensation Seeking Scale (SSS). The PGs showed significantly more chasing and had significantly poorer decision-making strategies than NPGs, particularly among males (F = 4.52, p <0.05). Random players were significantly less sensation seeking than...

  17. Panicum sect. Dichotomiflora (Hitchc. & Chase Honda e P. sect. Virgata Hitchc. & Chase ex Pilg. (Poaceae: Panicoideae: Paniceae no Brasil Panicum sect. Dichotomiflora (Hitchc. & Chase Honda and P. sect. Virgata Hitchc. & Chase ex Pilg. (Poaceae: Panicoideae: Paniceae in Brazil

    Adriana Guglieri

    2007-12-01

    Full Text Available (Panicum sect. Dichotomiflora (Hitchc. & Chase Honda e P. sect. Virgata Hitchc. & Chase ex Pilg. (Poaceae: Panicoideae: Paniceae no Brasil. Panicum L. subg. Panicum inclui cerca de 100 espécies predominantemente tropicais. Deste total, aproximadamente 50 espécies são americanas e ocorrem desde o Canadá até Argentina, Uruguai e Brasil. Está representado no Brasil por 30 espécies, três delas sem seção definida, e as demais distribuídas entre P. sect. Dichotomiflora (Hitchc. & Chase Honda, P. sect. Panicum, P. sect. Rudgeana (Hitchc. Zuloaga, P. sect. Urvilleana (Hitchc. & Chase Pilger e P. sect. Virgata Hitchc. & Chase ex Pilg. O presente trabalho tem como objetivo fornecer meios para a identificação das espécies de Panicum sect. Dichotomiflora e P. sect. Virgata nativas e exóticas naturalizadas ocorrentes no Brasil, contribuindo para o conhecimento da flora agrostológica brasileira e fornecendo subsídios para pesquisas em outras áreas. Para este estudo foram realizadas revisão bibliográfica, revisão de herbários, coletas e observação de populações no campo, bem como análise da superfície do segundo antécio em Microscopia Eletrônica de Varredura (MEV. Panicum sect. Dichotomiflora inclui cerca de 11 espécies neotropicais, das quais seis têm ocorrência confirmada no Brasil e ocorrem principalmente em ambientes úmidos como brejos e margens de cursos d'agua. Panicum sect. Virgata inclui aproximadamente oito espécies neotropicais, das quais quatro ocorrem no Brasil, em ambientes variados tais como cerrado, campos e brejos. O trabalho apresenta chaves para identificação dos grupos taxonômicos atualmente aceitos em Panicum e ocorrentes no Brasil, tabela comparativa das seções de Panicum subg. Panicum, bem como chave para identificação, descrições, dados de distribuição geográfica e da superfície do segundo antécio em MEV, ilustrações e fotomicrografias das espécies de P. sect. Dichotomiflora e P. sect

  18. 'Chasing the dragon': new knowledge for an old practice.

    Cordova, Juan P; Balan, Sabish; Romero, Jorge; Korniyenko, Aleksandr; Alviar, Carlos L; Paniz-Mondolfi, Alberto; Jean, Raymonde

    2014-01-01

    Heroin administration by "chasing the dragon," whereby the user places freebase heroin on aluminum foil, heats it below with a flame, and inhales the pyrolysate through a straw, can be associated with the rare development of a delayed-onset spongiform leukoencephalopathy. We report the case of a 46-year-old woman with a psychiatric diagnosis of depression and heroin dependence by "chasing the dragon" admitted with features of altered mental status and later development of catatonia, abulia, and akinetic mutism. A brain magnetic resonance image evidenced bilateral symmetric high-signal lesions in the white matter of the cerebrum and cerebellum on T2-weighted images compatible with toxic leukoencephalopathy. The patient's condition resolved after a hospital stay of 2 months with supportive treatment. Acute onset of neurobehavioral changes, including confusion, apathy, and cerebellar signs in a person with exposure to heroin, should prompt one to consider toxic leukoencephalopathy as a cause of presentation. PMID:21519216

  19. JPMorgan Chase London Whale H: Cross-Border Regulation

    Arwin G. Zeissler; Andrew Metrick

    2014-01-01

    As a global financial service provider, JPMorgan Chase (JPM) is supervised by banking regulatory agencies in different countries. Bruno Iksil, the derivatives trader primarily responsible for the $6 billion trading loss in 2012, was based in JPM’s London office. This office was regulated both by the Office of the Comptroller of the Currency (OCC) of the United States and by the Financial Services Authority (FSA), which served as the sole regulator of all financial services in the United Kingd...

  20. Chasing an Elusive Target With a Mobile Robot

    Coué, Christophe; Bessiere, Pierre

    2001-01-01

    This paper describes how a mobile robot (a six-wheeled Koala equiped with a PAL pan-tilt camera) can chase an elusive target (a remote controlled toy car) in an unknown and unconstrained environment. The first purpose of the paper is to demonstrate efficiency, simplicity, and adequacy of Bayesian Robot Programming (BRP) to quickly develop such applications. The second purpose of the paper is to illustrate that tremendous information compression ratio may be obtained by some pertinent sensori-...

  1. eCHASE: Sustainable Exploitation of Electronic Cultural Heritage

    Sinclair, Patrick; Lewis, Paul; Martinez, Kirk; Addis, Matthew; Prideaux, Daniel; Fina, Daniela; Da Bormida, Giorgio

    2005-01-01

    Europe’s digital cultural heritage content has tremendous exploitation potential in applications such as Education, Publishing, e-Commerce, Public Access and Tourism. Value is hugely amplified if the content can be aggregated, repurposed and distributed at a European level. The eCHASE project seeks to demonstrate that public-private partnerships between content holders and commercial service providers can create new services and a sustainable business based on access and exploitation of digit...

  2. Northern Lights Chase Tours : Experiences from Northern Norway

    Bertella, Giovanna

    2013-01-01

    This study is focused on the development of northern lights chase tourism, a particular type of northern lights tourism consisting in guided tours that have the goal to find good views of the northern lights. The theoretical approach is based on the understanding of the northern lights experience as a visual experience, and on the recognition of the tourism practitioners as the driving force to new product development. The empirical case concerns the recent development of northern lights chas...

  3. Adapt

    Bargatze, L. F.

    2015-12-01

    Active Data Archive Product Tracking (ADAPT) is a collection of software routines that permits one to generate XML metadata files to describe and register data products in support of the NASA Heliophysics Virtual Observatory VxO effort. ADAPT is also a philosophy. The ADAPT concept is to use any and all available metadata associated with scientific data to produce XML metadata descriptions in a consistent, uniform, and organized fashion to provide blanket access to the full complement of data stored on a targeted data server. In this poster, we present an application of ADAPT to describe all of the data products that are stored by using the Common Data File (CDF) format served out by the CDAWEB and SPDF data servers hosted at the NASA Goddard Space Flight Center. These data servers are the primary repositories for NASA Heliophysics data. For this purpose, the ADAPT routines have been used to generate data resource descriptions by using an XML schema named Space Physics Archive, Search, and Extract (SPASE). SPASE is the designated standard for documenting Heliophysics data products, as adopted by the Heliophysics Data and Model Consortium. The set of SPASE XML resource descriptions produced by ADAPT includes high-level descriptions of numerical data products, display data products, or catalogs and also includes low-level "Granule" descriptions. A SPASE Granule is effectively a universal access metadata resource; a Granule associates an individual data file (e.g. a CDF file) with a "parent" high-level data resource description, assigns a resource identifier to the file, and lists the corresponding assess URL(s). The CDAWEB and SPDF file systems were queried to provide the input required by the ADAPT software to create an initial set of SPASE metadata resource descriptions. Then, the CDAWEB and SPDF data repositories were queried subsequently on a nightly basis and the CDF file lists were checked for any changes such as the occurrence of new, modified, or deleted

  4. INFLUENCE OF AGE ON SWALLOWS OF A HIGHLY VISCOUS LIQUID BOLUS

    Weslania Viviane NASCIMENTO

    2015-03-01

    Full Text Available Background Swallow function has a decline with aging, mainly in those over 80 years old. In the population over 69 years, about 11% of subjects reported symptoms indicative of significant dysphagia. Objectives Our objective was to evaluate the hypothesis that older asymptomatic subjects before 80 years old have compensations to sustain a safe and efficient swallow, at least with swallows of liquid bolus. Methods We performed videofluoroscopic evaluation of swallows in 55 normal volunteers, a younger group with 33 subjects (16 men and 17 women aged 19 to 55 years, mean 35.5±9.8 years, and an older group with 22 subjects (15 men and 7 women aged 56 to 77 years, mean 64.8±6.8 years. The subjects swallowed in duplicate 5 mL and 10 mL of liquid barium with a pH of 7.9, density of 1.82 g/cm3, and viscosity of 895 cp. Results The mean duration of pharyngeal transit, pharyngeal clearance, upper esophageal sphincter opening, hyoid movement and oral-pharyngeal transit were longer in the younger group compared with the older group. The relation between pharyngeal clearance duration and hyoid movement duration was similar in younger and older subjects, for 5 mL and 10 mL bolus volumes. Conclusions On average, a highly viscous liquid bolus crosses the pharynx faster in older subjects (56-77 years old than in younger subjects (19-55 years old, which suggested an adaptation to the aging process to maintain a safe swallow.

  5. Physical Properties of Ethyl Methacrylate as a Bolus in Radiotherapy

    Bolus is a soft and resilient material which is used for increasing skin dose or to even out the irregular patient contour. The main property of various materials used presently as bolus is the water-equivalent electron density. Ethyl methacrylate is used as a soft-liner in dentistry and its physical and chemical properties are proved to be nontoxic for human body. The goal of this study was to assess the feasibility of using this material as bolus in radiotherapy and also evaluating some parameters such as mass, electron densities, and transmission factors. Computed tomography data from the sample material were acquired to assess mass and electron densities with various techniques (mA and kVp). Circular ROIs were delineated on CT DICOM images and densities were calculated using CT numbers. Transmission factors were calculated for 6 and 18 MV. Evaluation of our results are evident that showed that mass and electron densities of ethyl methacrylate are similar to those of water and soft tissue. Furthermore, transmission factors are close to those of water. According to the results of this study and other properties such as flexibility and harmlessness, it seems that ethyl methacrylate is a suitable material to be used as bolus in radiotherapy.

  6. Water bolus for electron irradiation of the ear canal

    Purpose: To demonstrate that water bolus in the external ear can decrease the dose inhomogeneity caused by auricular surface irregularities when the ear is in an electron-beam field. Methods and Materials: Three-dimensional (3D) dose distributions with and without water bolus in the external ear were calculated for a representative patient. The electron dose calculations were made using the Hogstrom pencil beam algorithm as implemented in 3D by Starkschall. To demonstrate the use of water bolus in the ear clinically, the case of a patient with squamous carcinoma of the concha who was treated with electrons is presented. Results: Water bolus markedly lessens the dose heterogeneity caused by the surface irregularities of the ear and the air in the external auditory canal. In the test case, the maximum dose was reduced by 25% using this technique. Conclusion: When the ear is in an electron beam field, warm water should be placed in the external auditory canal and concha. This maneuver may reduce the incidence of auricular complications that occur after electron-beam therapy

  7. Effects of Verbal Cue on Bolus Flow during Swallowing

    Daniels, Stephanie K.; Schroeder, Mae Fern; DeGeorge, Pamela C.; Corey, David M.; Rosenbek, John C.

    2007-01-01

    Purpose: To examine the effects of verbal cuing to initiate swallowing on bolus flow measures in healthy adults. Method: Videofluoroscopic examinations were completed in 12 healthy older adults (median age = 69 years) as they swallowed 5 ml of self-administered liquid barium in 2 conditions: verbally cued and noncued swallows. In the cued…

  8. 21 CFR 520.540b - Dexamethasone tablets and boluses.

    2010-04-01

    ... of dexamethasone. (2) Sponsor. See No. 000061 in § 510.600(c) of this chapter. (3) Conditions of use. (i) Dexamethasone bolus is indicated in cases where cattle and horses require additional steroid... use in viral infections during the viremic stage. With bacterial infections, appropriate...

  9. SU-C-213-06: Dosimetric Verification of 3D Printed Electron Bolus

    Rasmussen, K; Corbett, M; Pelletier, C; Huang, Z; Feng, Y; Jung, J [East Carolina Univ, Greenville, NC (United States)

    2015-06-15

    Purpose: To determine the dosimetric effect of 3D printed bolus in an anthropomorphic phantom. Methods: Conformable bolus material was generated for an anthropomorphic phantom from a DICOM volume. The bolus generated was a uniform expansion of 5mm applied to the nose region of the phantom, as this is a difficult area to uniformly apply bolus clinically. A Printrbot metal 3D Printer using PLA plastic generated the bolus. A 9MeV anterior beam with a 5cm cone was used to deliver dose to the nose of the phantom. TLD measurements were compared to predicted values at the phantom surface. Film planes were analyzed for the printed bolus, a standard 5mm bolus sheet placed on the phantom, and the phantom with no bolus applied to determine depth and dose distributions. Results: TLDs measured within 2.5% of predicted value for the 3D bolus. Film demonstrated a more uniform dose distribution in the nostril region for the 3d printed bolus than the standard bolus. This difference is caused by the air gap created around the nostrils by the standard bolus, creating a secondary build-up region. Both demonstrated a 50% central axis dose shift of 5mm relative to the no bolus film. HU for the bolus calculated the PLA electron density to be ∼1.1g/cc. Physical density was measured to be 1.3g/cc overall. Conclusion: 3D printed PLA bolus demonstrates improved dosimetric performance to standard bolus for electron beams with complex phantom geometry.

  10. SU-C-213-03: Custom 3D Printed Boluses for Radiation Therapy

    Zhao, B; Yang, M; Yan, Y; Rahimi, A; Chopra, R; Jiang, S [UT Southwestern Medical Center, Dallas, TX (United States)

    2015-06-15

    Purpose: To develop a clinical workflow and to commission the process of creating custom 3d printed boluses for radiation therapy. Methods: We designed a workflow to create custom boluses using a commercial 3D printer. Contours of several patients were deformably mapped to phantoms where the test bolus contours were designed. Treatment plans were created on the phantoms following our institutional planning guideline. The DICOM file of the bolus contours were then converted to stereoLithography (stl) file for the 3d printer. The boluses were printed on a commercial 3D printer using polylactic acid (PLA) material. Custom printing parameters were optimized in order to meet the requirement of bolus composition. The workflow was tested on multiple anatomical sites such as skull, nose and chest wall. The size of boluses varies from 6×9cm2 to 12×25cm2. To commission the process, basic CT and dose properties of the printing materials were measured in photon and electron beams and compared against water and soft superflab bolus. Phantoms were then scanned to confirm the placement of custom boluses. Finally dose distributions with rescanned CTs were compared with those computer-generated boluses. Results: The relative electron density(1.08±0.006) of the printed boluses resemble those of liquid tap water(1.04±0.004). The dosimetric properties resemble those of liquid tap water(1.04±0.004). The dosimetric properties were measured at dmax with an ion chamber in electron and photon open beams. Compared with solid water and soft bolus, the output difference was within 1% for the 3D printer material. The printed boluses fit well to the phantom surfaces on CT scans. The dose distribution and DVH based on the printed boluses match well with those based on TPS generated boluses. Conclusion: 3d printing provides a cost effective and convenient solution for patient-specific boluses in radiation therapy.

  11. SU-C-213-06: Dosimetric Verification of 3D Printed Electron Bolus

    Purpose: To determine the dosimetric effect of 3D printed bolus in an anthropomorphic phantom. Methods: Conformable bolus material was generated for an anthropomorphic phantom from a DICOM volume. The bolus generated was a uniform expansion of 5mm applied to the nose region of the phantom, as this is a difficult area to uniformly apply bolus clinically. A Printrbot metal 3D Printer using PLA plastic generated the bolus. A 9MeV anterior beam with a 5cm cone was used to deliver dose to the nose of the phantom. TLD measurements were compared to predicted values at the phantom surface. Film planes were analyzed for the printed bolus, a standard 5mm bolus sheet placed on the phantom, and the phantom with no bolus applied to determine depth and dose distributions. Results: TLDs measured within 2.5% of predicted value for the 3D bolus. Film demonstrated a more uniform dose distribution in the nostril region for the 3d printed bolus than the standard bolus. This difference is caused by the air gap created around the nostrils by the standard bolus, creating a secondary build-up region. Both demonstrated a 50% central axis dose shift of 5mm relative to the no bolus film. HU for the bolus calculated the PLA electron density to be ∼1.1g/cc. Physical density was measured to be 1.3g/cc overall. Conclusion: 3D printed PLA bolus demonstrates improved dosimetric performance to standard bolus for electron beams with complex phantom geometry

  12. SU-C-213-03: Custom 3D Printed Boluses for Radiation Therapy

    Purpose: To develop a clinical workflow and to commission the process of creating custom 3d printed boluses for radiation therapy. Methods: We designed a workflow to create custom boluses using a commercial 3D printer. Contours of several patients were deformably mapped to phantoms where the test bolus contours were designed. Treatment plans were created on the phantoms following our institutional planning guideline. The DICOM file of the bolus contours were then converted to stereoLithography (stl) file for the 3d printer. The boluses were printed on a commercial 3D printer using polylactic acid (PLA) material. Custom printing parameters were optimized in order to meet the requirement of bolus composition. The workflow was tested on multiple anatomical sites such as skull, nose and chest wall. The size of boluses varies from 6×9cm2 to 12×25cm2. To commission the process, basic CT and dose properties of the printing materials were measured in photon and electron beams and compared against water and soft superflab bolus. Phantoms were then scanned to confirm the placement of custom boluses. Finally dose distributions with rescanned CTs were compared with those computer-generated boluses. Results: The relative electron density(1.08±0.006) of the printed boluses resemble those of liquid tap water(1.04±0.004). The dosimetric properties resemble those of liquid tap water(1.04±0.004). The dosimetric properties were measured at dmax with an ion chamber in electron and photon open beams. Compared with solid water and soft bolus, the output difference was within 1% for the 3D printer material. The printed boluses fit well to the phantom surfaces on CT scans. The dose distribution and DVH based on the printed boluses match well with those based on TPS generated boluses. Conclusion: 3d printing provides a cost effective and convenient solution for patient-specific boluses in radiation therapy

  13. Chasing the negawatt: visualization for sustainable living.

    Bartram, Lyn; Rodgers, Johnny; Muise, Kevin

    2010-01-01

    Energy and resource management is an important and growing research area at the intersection of conservation, sustainable design, alternative energy production, and social behavior. Energy consumption can be significantly reduced by simply changing how occupants inhabit and use buildings, with little or no additional costs. Reflecting this fact, an emerging measure of grid energy capacity is the negawatt: a unit of power saved by increasing efficiency or reducing consumption.Visualization clearly has an important role in enabling residents to understand and manage their energy use. This role is tied to providing real-time feedback of energy use, which encourages people to conserve energy.The challenge is to understand not only what kinds of visualizations are most effective but also where and how they fit into a larger information system to help residents make informed decisions. In this article, we also examine the effective display of home energy-use data using a net-zero solar-powered home (North House) and the Adaptive Living Interface System (ALIS), North House's information backbone. PMID:20650713

  14. Tournament Chasing NASCAR Style: Driver Incentives in Stock Car Racing's Playoff Season

    J Brian O'Roark; Wood, William C.; Benjamin Demblowski

    2012-01-01

    This paper applies tournament theory to NASCAR racing's playoff season, the Chase for the Cup. The consequences of a mixed tournament with the top 10 and lower-ranked drivers racing simultaneously are explored and tested. Using individual driver and race data, we empirically show that Chase races experience more accidents. In the lead up to the Chase, the relative position of drivers to the leader in terms of rank is more important in predicting accidents than the absolute position in terms o...

  15. Revisiting Chase Termination for Existential Rules and their Extension to Nonmonotonic Negation

    Baget, Jean-François; Garreau, Fabien; Mugnier, Marie-Laure; Rocher, Swan

    2014-01-01

    Existential rules have been proposed for representing ontological knowledge, specifically in the context of Ontology- Based Data Access. Entailment with existential rules is undecidable. We focus in this paper on conditions that ensure the termination of a breadth-first forward chaining algorithm known as the chase. Several variants of the chase have been proposed. In the first part of this paper, we propose a new tool that allows to extend existing acyclicity conditions ensuring chase termin...

  16. 21 CFR 520.1660c - Oxytetracycline hydrochloride tablets/boluses.

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Oxytetracycline hydrochloride tablets/boluses. 520....1660c Oxytetracycline hydrochloride tablets/boluses. (a) Specifications. Each tablet or bolus contains 250, 500, or 1,000 milligrams of oxytetracycline hydrochloride. (b) Sponsors. For sponsors in §...

  17. A simple formula to determine the bolus thickness on an oblique surface

    For certain clinical situations such as breast treatments, a bolus is used and must be accounted for in monitor unit calculations. Because of the oblique incidence involved, the thickness of bolus traversed by the radiation beam, as opposed to its nominal thickness, must be used. Using principles of geometry, a simple method is derived to calculate the thickness of bolus for these calculations

  18. Building 059: Phase 1 Pipe Chase Room Remediation

    This report documents the Phase I activities and results of the Building 059 Remediation project. The project consisted of removing, packaging, and shipping approximately 30 linear feet of 5-ft-dia activated steel vacuum duct and supports, over 100 tons of activated sand, and miscellaneous other radioactive waste for burial at the DOE radioactive burial site in Hanford, Washington. A total of 4562 ft3 of low specific activity waste was disposed of during the project. Following removal of the activated materials, the region of water intrusion into the Pipe Chase Room was identified and sealed. All technical objectives of the Phase I portion of the project were achieved

  19. Chasing literacy reading and writing in an age of acceleration

    Keller, Daniel

    2013-01-01

    Arguing that composition should renew its interest in reading pedagogy and research, Chasing Literacy offers writing instructors and literacy scholars a framework for understanding and responding to the challenges posed by the proliferation of interactive and multimodal communication technologies in the twenty-first century.Employing case-study research of student reading practices, Keller explores reading-writing connections in new media contexts. He identifies a culture of acceleration-a gathering of social, educational, economic, and technological forces that reinforce the values of speed,

  20. Intravenous contrast material administration at high-pitch dual-source CT pulmonary angiography: Test bolus versus bolus-tracking technique

    Kerl, J. Matthias, E-mail: matthias.kerl@gmail.com [Institute for Diagnostic and Interventional Radiology, Clinic of the Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Lehnert, Thomas, E-mail: Thomas.lehnert@kgu.de [Institute for Diagnostic and Interventional Radiology, Clinic of the Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Schell, Boris, E-mail: boris.schell@googlemail.com [Institute for Diagnostic and Interventional Radiology, Clinic of the Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Bodelle, Boris, E-mail: Boris.bodelle@kgu.de [Institute for Diagnostic and Interventional Radiology, Clinic of the Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Beeres, Martin, E-mail: Martin.Beeres@kgu.de [Institute for Diagnostic and Interventional Radiology, Clinic of the Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Jacobi, Volkmar, E-mail: v.jacobi@em.uni-frankfurt.de [Institute for Diagnostic and Interventional Radiology, Clinic of the Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Vogl, Thomas J., E-mail: T.Vogl@em.uni-frankfurt.de [Institute for Diagnostic and Interventional Radiology, Clinic of the Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Bauer, Ralf W., E-mail: ralfwbauer@aol.com [Institute for Diagnostic and Interventional Radiology, Clinic of the Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany)

    2012-10-15

    Purpose: To compare test bolus and bolus tracking for the determination of scan delay of high-pitch dual-source CT pulmonary angiography in patients with suspected pulmonary embolism using 50 ml of contrast material. Materials and methods: Data of 80 consecutive patients referred for CT pulmonary angiography were evaluated. All scans were performed on a 128-channel dual-source CT scanner with a high-pitch protocol (pitch 3.0, 100 kV, 180 mA s). Contrast enhancement was achieved by injecting 50 ml of iomeprol followed by a saline chaser of 50 ml injected at a rate of 4 ml/s. The scan delay was determined using either the test bolus (n = 40) or bolus tracking (n = 40) technique. Test bolus required another 15 ml CM to determine time to peak enhancement of the contrast bolus within the pulmonary trunk. Attenuation profiles in the pulmonary trunk and on segmental level as well as in the ascending aorta were measured to evaluate the timing techniques. Additionally, overall image quality was evaluated. Results: In all patients an adequate and homogeneous contrast enhancement of more than 250 HU was achieved in the pulmonary arteries. No statistically significant difference between test bolus and bolus tracking was found regarding attenuation of the pulmonary arteries or overall image quality. However, using bolus tracking 15 ml CM less was injected. Conclusion: A homogeneous opacification of the pulmonary arteries and sufficient image quality can be achieved with both the bolus tracking and test bolus techniques with significant lower contrast doses compared to conventional contrast material injection protocols.

  1. A customized bolus produced using a 3-dimensional printer for radiotherapy.

    Shin-Wook Kim

    Full Text Available OBJECTIVE: Boluses are used in high-energy radiotherapy in order to overcome the skin sparing effect. In practice though, commonly used flat boluses fail to make a perfect contact with the irregular surface of the patient's skin, resulting in air gaps. Hence, we fabricated a customized bolus using a 3-dimensional (3D printer and evaluated its feasibility for radiotherapy. METHODS: We designed two kinds of bolus for production on a 3D printer, one of which was the 3D printed flat bolus for the Blue water phantom and the other was a 3D printed customized bolus for the RANDO phantom. The 3D printed flat bolus was fabricated to verify its physical quality. The resulting 3D printed flat bolus was evaluated by assessing dosimetric parameters such as D1.5 cm, D5 cm, and D10 cm. The 3D printed customized bolus was then fabricated, and its quality and clinical feasibility were evaluated by visual inspection and by assessing dosimetric parameters such as Dmax, Dmin, Dmean, D90%, and V90%. RESULTS: The dosimetric parameters of the resulting 3D printed flat bolus showed that it was a useful dose escalating material, equivalent to a commercially available flat bolus. Analysis of the dosimetric parameters of the 3D printed customized bolus demonstrated that it is provided good dose escalation and good contact with the irregular surface of the RANDO phantom. CONCLUSIONS: A customized bolus produced using a 3D printer could potentially replace commercially available flat boluses.

  2. EFFECT OF A BITTER BOLUS ON ORAL, PHARYNGEAL AND ESOPHAGEAL TRANSIT OF HEALTHY SUBJECTS

    Leda Maria Tavares ALVES

    2013-03-01

    Full Text Available Context During swallowing, boluses stimulate sensory receptors of the oral, pharyngeal, laryngeal, and esophageal regions. Sweet and tasteless foods are more acceptable for swallowing than bitter foods. A bitter bolus is unpleasant for most subjects. Our hypothesis was that the ingestion of a bitter bolus might alter the oral behavior, pharyngeal and esophageal transit when compared to a sweet bolus. Objective To evaluate whether the bitter taste of a liquid bolus causes alteration on oral, pharyngeal and/or esophageal transit in normal subjects in comparison with sweet bolus.' Method Scintigraphic evaluation of oral, pharyngeal and esophageal transit was performed in 43 asymptomatic subjects, 22 women and 21 men, ages 23-71 years, without problems with the ingestion of liquid and solid foods, and without digestive, cardiac or neurologic diseases. Each subject swallowed in random sequence and at room temperature 5 mL of a liquid bolus with bitter taste, prepared with 50 mL of water with 2 g of leaves of Peumus boldus, heated until boiling (boldus tea, and 5 mL of a liquid bolus with sweet taste, prepared with 50 mL of water with 3 g of sucrose, both labeled with 37 MBq of technetium phytate (Tc99m. Results There was no difference between the bitter bolus and the sweet bolus in mouth, pharynx and esophageal transit and clearance duration and in the amount of residues. Conclusion A bitter bolus, considered an unpleasant bolus, does not alter the duration of oral, pharyngeal and esophageal phases of swallowing, when compared with a sweet bolus, considered a pleasant bolus.

  3. Transversus Abdominis Plane Catheter Bolus Analgesia after Major Abdominal Surgery

    Nils Bjerregaard

    2012-01-01

    Full Text Available Purpose. Transversus abdominis plane (TAP blocks have been shown to reduce pain and opioid requirements after abdominal surgery. The aim of the present case series was to demonstrate the use of TAP catheter injections of bupivacaine after major abdominal surgery. Methods. Fifteen patients scheduled for open colonic resection surgery were included. After induction of anesthesia, bilateral TAP catheters were placed, and all patients received a bolus dose of 20 mL bupivacaine 2.5 mg/mL with epinephrine 5 μg/mL through each catheter. Additional bolus doses were injected bilaterally 12, 24, and 36 hrs after the first injections. Supplemental pain treatment consisted of paracetamol, ibuprofen, and gabapentin. Intravenous morphine was used as rescue analgesic. Postoperative pain was rated on a numeric rating scale (NRS, 0–10 at regular predefined intervals after surgery, and consumption of intravenous morphine was recorded. Results. The TAP catheters were placed without any technical difficulties. NRS scores were ≤3 at rest and ≤5 during cough at 4, 8, 12, 18, 24, and 36 hrs after surgery. Cumulative consumption of intravenous morphine was 28 (23–48 mg (median, IQR within the first 48 postoperative hours. Conclusion. TAP catheter bolus injections can be used to prolong analgesia after major abdominal surgery.

  4. Analysis of bolus formation from the micropipette ejection systems

    Meng, Diwen; Mirbod, Parisa

    2013-11-01

    Ejection of drugs from micropipettes has significant applications in biomedical research and clinical studies, however little is known about the dynamics of the process involved. The experimental results show that micropipette ejection systems operate in a tip Reynolds number (Ret). A series of experiments was performed from a micropipette to visualize the shape of the droplet. The observations led to the following conclusions: a) A nearly spherical bolus, closely corresponding to Sampson flow through a circular orifice, could be achieved provided at Ret 1 an axial jet develops. Consequently, the transition point between the flow domains represents an important operating point. In this research, laminar is demarcated from turbulent regime by studying the influence of the various material and process parameters on the transition point. Three-dimensional numerical simulations on bolus formation and growth with different tip diameter were investigated and the results were validated with the experimental observations. Effects of fluid physical properties, operation conditions and tip exit size on bolus behavior were also analyzed.

  5. Cycloheximide Chase Analysis of Protein Degradation in Saccharomyces cerevisiae.

    Buchanan, Bryce W; Lloyd, Michael E; Engle, Sarah M; Rubenstein, Eric M

    2016-01-01

    Regulation of protein abundance is crucial to virtually every cellular process. Protein abundance reflects the integration of the rates of protein synthesis and protein degradation. Many assays reporting on protein abundance (e.g., single-time point western blotting, flow cytometry, fluorescence microscopy, or growth-based reporter assays) do not allow discrimination of the relative effects of translation and proteolysis on protein levels. This article describes the use of cycloheximide chase followed by western blotting to specifically analyze protein degradation in the model unicellular eukaryote, Saccharomyces cerevisiae (budding yeast). In this procedure, yeast cells are incubated in the presence of the translational inhibitor cycloheximide. Aliquots of cells are collected immediately after and at specific time points following addition of cycloheximide. Cells are lysed, and the lysates are separated by polyacrylamide gel electrophoresis for western blot analysis of protein abundance at each time point. The cycloheximide chase procedure permits visualization of the degradation kinetics of the steady state population of a variety of cellular proteins. The procedure may be used to investigate the genetic requirements for and environmental influences on protein degradation. PMID:27167179

  6. Group chase and escape model with chasers' interaction

    Saito, Takuya; Nakamura, Tomomichi; Ohira, Toru

    2016-04-01

    Group chase and escape is a new direction of studying collective behaviors merged with the traditional mathematical problems of chases and escapes proposed by Kamimura and Ohira in 2010. In their model, the chasers recognize only the escapees and pursue the nearest neighbor escapee, and the escapees recognize only the chasers and flee from the nearest neighbor chaser. We call the basic moving rule the nearest opponent interaction (NOI) strategy. In this paper we introduce a new strategy in the model. It is a local interaction that the chasers do not get too close each other, where we call the chasers' local interaction (CLI) strategy. The result of comparisons of the two strategies shows that when the number of the chasers is relatively small compared to the number of the escapees, the trapping time by the CLI strategy is much shorter than that by the NOI strategy. On the other hand, when the number of the chasers is larger than that of the escapees, this advantage of the CLI strategy does not appear. Also, we find that although chasers form clusters (spatial aggregates of chasers) when we apply the NOI strategy, the clusters appear less when we apply the CLI strategy.

  7. The influence of a solid and liquid bolus on food-stimulated gastroesophageal reflux

    Naeser, A.; Behrens, J.K.; Vejen-Christiansen, L.; Funch-Jensen, P.; Thommesen, P. (Aarhus Kommunehospital (Denmark). GI Motility Lab. Aarhus Kommunehospital (Denmark). Dept. of Diagnostic Radiology R)

    1992-02-01

    Using a radiological method to demonstrate food-stimulated gastroesophageal reflux (GER), a comparative study was carried out employing a solid, already validated bolus versus a liquid one. One hundred and four consecutive patients received both a solid and a liquid bolus in randomized order. GER was observed in 37 (35.6%) patients receiving the solid bolus versus 28 (26.9%) with the liquid one. This means that the solid bolus provokes significantly more reflux (P<0.02). GER, grade II (reflux above the level of the carina), occurred equally often as a result of both types of bolus, however. The study suggests that significant, food-stimulated GER is independent of the consistency of the foodstuffs and may be detected employing a liquid bolus. This result might be used in the examination of infants for GER, using milk as a food stimulus. (orig.).

  8. The influence of a solid and liquid bolus on food-stimulated gastroesophageal reflux

    Using a radiological method to demonstrate food-stimulated gastroesophageal reflux (GER), a comparative study was carried out employing a solid, already validated bolus versus a liquid one. One hundred and four consecutive patients received both a solid and a liquid bolus in randomized order. GER was observed in 37 (35.6%) patients receiving the solid bolus versus 28 (26.9%) with the liquid one. This means that the solid bolus provokes significantly more reflux (P<0.02). GER, grade II (reflux above the level of the carina), occurred equally often as a result of both types of bolus, however. The study suggests that significant, food-stimulated GER is independent of the consistency of the foodstuffs and may be detected employing a liquid bolus. This result might be used in the examination of infants for GER, using milk as a food stimulus. (orig.)

  9. Postprandial transduodenal bolus transport is regulated by complex peristaltic sequence

    Huan Nam Nguyen; Ron Winograd; Gerson Ricardo Souza Domingues; Frank Lammert

    2006-01-01

    AIM: To study the relationship between the patterns of postprandial peristalsis and transduodenal bolus transport in healthy subjects.METHODS: Synchronous recording of chyme transport and peristaltic activity was performed during the fasting state and after administration of a test meal using a special catheter device with cascade configuration of impedance electrodes and solid-state pressure transducers. The catheter was placed into the duodenum,where the first channel was located in the first part of the duodenum and the last channel at the duodenojejunal junction. After identification of previously defined chyme transport patterns the associated peristaltic patterns were analyzed.RESULTS: The interdigestive phase 3 complex was reliably recorded with both techniques. Of 497 analyzed impedance bolus transport events, 110 (22%) were short-spanned propulsive, 307 (62%) long-spanned propulsive, 70 (14%)complex propulsive, and 10 (2%) retrograde transport.Short-spanned chyme transports were predominantly associated with stationary or propagated contractions propagated over short distance. Long-spanned and complex chyme transports were predominantly associated with propulsive peristaltic patterns, which were frequently complex and comprised multiple contractions. Propagated double wave contraction, propagated contraction with a clustered contraction, and propagated cluster of contractions have been identified to be an integralted part of a peristaltic sequence in human duodenum.CONCLUSION: Combined impedancometry andmanometry improves the analysis of the peristaltic patterns that are associated with postprandial transduodenal chyme transport. Postprandial transduodenal bolus transport is regulated by propulsive peristaltic patterns, which are frequently complex but well organized. This finding should be taken into consideration in the analysis of intestinal motility studies.

  10. Optimal Set-point Chasing of Position Moored Vessel

    Fang, Shaoji; Blanke, Mogens; Bernt, Leira

    2010-01-01

    Dynamic positioning of surface vessels moored to the seabed via a spread mooring system are referred to as position mooring (PM), the main objective of which is to keep the vessel within a small radius from a given position while preventing mooring line breakage. When environmental loads become...... high, position mooring systems apply thruster forces to protect mooring lines and position accuracy may need be relaxed. This paper suggests an new position chasing algorithm that works entirely online, is optimal according to a criterion and can protect any number of mooring lines simultaneously....... Tensions of all mooring lines are included in a cost function where the criticality for each mooring line determine individual weights. With this strategy, external environment effects are included directly by without needing predefined tabular settings of environmental loads as in earlier approaches...

  11. NO2 DOAS Measurements of Traffic Emissions by Chasing Cars

    Zhu, Ying; Lipkowitsch, Ivo; Chan, Ka Lok; Bräu, Melanie; Wenig, Mark

    2016-04-01

    On this poster we present NO2 measurements using a Cavity-Enhanced DOAS on a measurement bus which we used to chase other vehicles to measure their NO2 emissions. Emissions of nitrogen oxides from on-road vehicles have received highly attention recently due to the increasing trend of ambient NOx level. It is particularly important to identify and quantify the direct emission and secondary formation of NO2 contributed by traffic emissions, in order to study the impact to the local air quality. We sampled on-road emissions in different environments and different driving conditions (e.g. urban, highway, different speeds). We analyse the data set in terms of spatial and temporal variability to search for temporal and spatial patterns. We present mean values sorted for different vehicle types, distance to the target car and travelling speeds to provide an emission data base from this measurement study.

  12. A Single-Molecule Hershey-Chase Experiment

    Van Valen, David; Chen, Yi-Ju; Tuson, Hannah; Wiggins, Paul; Phillips, Rob

    2012-01-01

    Ever since Hershey and Chase used phages to establish DNA as the carrier of genetic information in 1952, the precise mechanisms of phage DNA translocation have been a mystery. While bulk measurements have set a time scale for in vivo DNA translocation during bacteriophage infection, measurements of DNA ejection by single bacteriophages have only been made in vitro. Here, we present direct visualization of single bacteriophages infecting individual Escherichia coli cells. For bacteriophage lambda, we establish a mean ejection time of roughly 5 minutes with significant cell-to-cell variability, including pausing events. In contrast, corresponding in vitro single-molecule ejections take only 10 seconds to reach completion and do not exhibit significant variability. Our data reveal that the velocity of ejection for two different genome lengths collapses onto a single curve. This suggests that in vivo ejections are controlled by the amount of DNA ejected, in contrast with in vitro DNA ejections, which are governed...

  13. Child and adolescent service experience (ChASE): measuring service quality and therapeutic process.

    Day, Crispin; Michelson, Daniel; Hassan, Imren

    2011-11-01

    OBJECTIVES. Dissatisfaction with services has been associated with poorer child mental health outcomes, early treatment termination as well as disagreements over the nature of mental health difficulties, reasons for referral and therapy goals. The development of straightforward, reliable, and accurate methods of eliciting service users' views is essential within child and adolescent mental health care. This paper describes the development of the child and adolescent service experience (ChASE), a tool to measure children and young people's service experience DESIGN. The study comprises a non-experimental, cross-sectional design. METHODS. Participants were 132 mental health service users aged 8-18 years. Participants and their main carer completed the ChASE, Parent Satisfaction Questionnaire (PSQ) (Stallard, 1996) and Strengths and Difficulties (SDQ) Impact Supplement. Clinicians completed the SDQ Impact Supplement and provided clinical activity data. A sub-sample of participants completed the ChASE on a second occasion, 6 weeks after the completion of the first questionnaire. RESULTS. Scrutiny of ChASE data indicated high levels of completion. Principal axis factoring identified three factors within the ChASE: Relationship, Privacy, and Session Activity. The ChASE has good internal consistency and test-retest reliability. Significant correlations were found between the ChASE and carer satisfaction, service use, and youth clinical outcomes. CONCLUSIONS. The ChASE is a short, psychometrically robust tool for routine measurement of children, and young people's experience of mental health services, which users can complete easily. The results underline the importance of alliance factors to children and young people and their association with clinical improvement as well as the potential for the ChASE to be used a measure of children's therapeutic progress and alliance. PMID:22003953

  14. Impact of bolus volume on small intestinal intra-luminal impedance in healthy subjects

    Nam; Q; Nguyen; Laura; K; Bryant; Carly; M; Burgstad; Robert; J; Fraser; Daniel; Sifrim; Richard; H; Holloway

    2010-01-01

    AIM: To assess the impact of bolus volume on the characteristics of small intestinal (SI) impedance signals.METHODS: Concurrent SI manometry-impedance measurements were performed on 12 healthy volunteers to assess the pattern of proximal jejunal fluid bolus movement over a 14 cm-segment.Each subject was given 34 boluses of normal saline (volume from 1 to 30 mL) via the feeding tube placed immediately above the proximal margin of the studied segment.A bolus-induced impedance event occurred if there was > 12%...

  15. Split-bolus MR urography: synchronous visualization of obstructing vessels and collecting system in children.

    Battal, Bilal; Kocaoğlu, Murat; Akgün, Veysel; İnce, Selami; Gök, Faysal; Taşar, Mustafa

    2015-01-01

    Several vascular abnormalities related with urinary system such as crossing accessory renal vessels, retroiliac ureters, retrocaval ureters, posterior nutcracker syndrome, and ovarian vein syndrome may be responsible for urinary collecting system obstruction. Split-bolus magnetic resonance urography (MRU) using contrast material as two separate bolus injections provides superior demonstration of the collecting system and obstructing vascular anomalies simultaneously and enables accurate preoperative radiologic diagnosis. In this pictorial review we aimed to outline the split-bolus MRU technique in children, list the coexisting congenital collecting system and vascular abnormalities, and exhibit the split-bolus MRU appearances of concurrent urinary collecting system and vascular abnormalities. PMID:26359874

  16. A New Chase-type Soft-decision Decoding Algorithm for Reed-Solomon Codes

    Tang, Siyun; Member, Xiao Ma

    2013-01-01

    This paper addresses three relevant issues arising in designing Chase-type algorithms for Reed-Solomon codes: 1) how to choose the set of testing patterns; 2) given the set of testing patterns, what is the optimal testing order in the sense that the most-likely codeword is expected to appear earlier; and 3) how to identify the most-likely codeword. A new Chase-type soft-decision decoding algorithm is proposed, referred to as tree-based Chase-type algorithm. The proposed algorithm takes the se...

  17. Comparison of bolus remifentanil versus bolus fentanyl for blunting cardiovascular intubation responses in children: a randomized, double-blind study

    YANG Quan-yong; XUE Fu-shan; LIAO Xu; LIU He-ping; LUO Mao-ping; XU Ya-chao; LIU Yi; ZHANG Yan-ming

    2009-01-01

    Background The authors found no study to compare the efficacy of bolus dose fentanyl and remifentanil blunting the cardiovascular intubation response in children, so they designed this randomized, double-blind clinical study to assess the effects of remifentanil 2 ug/kg and fentanyl 2 ug/kg by bolus injection on the cardiovascular intubation response in healthy children.Methods One hundred and two children, the American Society of Anesthesiologists (ASA) physical status 1-2 and scheduled for elective plastic surgery under general anesthesia, were randomly divided into one of two groups to receive the following treatments in a double blind manner: remifentanil 2 ug/kg (Group R) and fentanyl 2 ug/kg (Group F) when anesthesia was induced with propofol and vecuronium. The orotracheal intubation was performed using a direct laryngoscope. Blood pressure (BP) and heart rate (HR) were recorded before anesthesia induction (baseline values), immediately before intubation, at intubation and every minute for 5 minutes after intubation. The percent changes of systolic blood pressure (SBP) and HR relative to baseline values and the rate pressure product (RPP) at every observing point were calculated. The incidences of SBP and HR percent changes >30% of baseline values and RPP >22 000 during the observation were recorded. Results There were no significant differences between groups in the demographic data, baseline values of BP and HR and the intubation time. As compared to baseline values, BP, HR and RPP at intubation and their maximum values during observation increased significantly in Group F, but they all decreased significantly in Group R. BP, HR and RPP at all observed points, and their maximum values during the observation, were significantly different between groups. There were also significant differences between groups in the percent change of SBP and HR relative to baseline values at all observed points and their maximum percent changes during the observation. The

  18. Bolus injection of acetylcholine terminates atrial fibrillation in rats.

    Fleidervish, Ilya A; Goldberg, Yuri; Ovsyshcher, I Eli

    2008-01-28

    It is well established that a tonic increase in the availability of the atrial muscarinic K(+) channels, either by enhanced vagal tone or by steady infusion of a low-dose of cholinergic or adenosine receptor agonists, promotes the genesis of atrial fibrillation. Here, we aimed to test the hypothesis that bolus administration of a muscarinic receptor agonist would destabilize and terminate atrial arrhythmia by uniformly and transiently activating K(+) channels throughout the atria, and that if the agonist was rapidly hydrolysable, it would dissipate before the more tonic, pro-arrhythmic effects could take hold. The episodes of untreated atrial fibrillation, induced in anesthetized rats by programmed electrical stimulation via trans-esophageal bipolar catheter, lasted on average 8.6+/-2.2 min (n=32). Intravenous injection of a model hydrolysable muscarinic agonist, acetylcholine (0.2 mg/kg body weight), converted atrial fibrillation into sinus rhythm within 8.4+/-1.9 s (n=10, Ppre-atrial fibrillation values within 10-20 s of injection. In conclusion, our evidence indicates that bolus administration of rapidly hydrolysable muscarinic agonist could be an effective way to pharmacologically terminate atrial fibrillation and restore sinus rhythm. PMID:18078927

  19. 78 FR 23800 - JPMorgan Chase & Co., et al.; Notice of Application

    2013-04-22

    ... obligation to a JPMorgan Chase Third Party Fund, will not be subject to condition 3 below. All other side-by... documents, rather than by negotiable certificates that could be misappropriated. Applicants assert...

  20. Chase Global Markets: Defining New Business Models in the Investment Bank Industry

    Woodham, Richard; Ross, Jeanne W.

    2002-01-01

    Like most financial institutions, Chase Global Markets (now part of J.P. Morgan Chase) found that e-business opportunities challenged its core business model. The Global Markets business serves large institutional investors (as opposed to individual investors) and thus handles very large transactions. The nature of the business creates unique challenges in an ebusiness environment, where investors want more competitor comparisons online but prefer to complete their transactions with a persona...

  1. Avidin chase can reduce myelotoxicity associated with radioimmunotherapy of experimental liver micrometastases in mice

    Myelotoxicity is the main factor which decides the maximum tolerated dose (MTD) in radioimmunotherapy (RIT). Since bone marrow is mostly irradiated from blood radioactivity, enhancing the clearance of unbound circulating radiolabeled antibody is important to reduce myelotoxicity and to increase the MTD. We applied the avidin chase method, which was devised to obtain high tumor-to-background ratios in tumor-targeting, to RIT of experimental liver micrometastases and evaluated its influence on the side effects and therapeutic outcome. Seven days after intrasplenic injection of human colon cancer LS174T cells, nude mice were intravenously injected with biotinylated 131I-labeled anti-CEA monoclonal antibody (MAb) (24-38 μg, 11.1 MBq). Mice of the chase group then received an intravenous injection of avidin twice (24 and 30 h, 72-115 μg each). Biodistribution, side effects (white blood cell counts and body weight change), and short- and long-term therapeutic effects were determined. Avidin chase markedly accelerated the clearance of radiolabeled MAb from the blood (P<0.0001) and normal tissues, resulting in milder leukocytopenia and body weight loss, both of which recovered earlier than in the non-chase group (P<0.01). The tumor uptake of radiolabeled MAb was also decreased by avidin chase, but the metastases-to-background ratios were increased. Avidin chase gave the therapeutic gain ratio of 1.89. Treated groups with and without avidin chase showed significant therapeutic effects compared to the non-treated group. There was no significant difference in the therapeutic effects between the two treated groups. Avidin chase effectively reduced the side effects of RIT and should increase the MTD. (author)

  2. Correlations between aorto-popliteal bolus transit speed and aortic and popliteal bolus transit time during CT angiography of aortoiliac and lower extremity arteries

    Purpose: The purpose of this study was to investigate correlations between the aorto-popliteal bolus transit speed and aortic and popliteal bolus transit time in order to evaluate the possibility for prediction of bolus transit speed by single test injection technique. Materials and methods: Approval was obtained from our institutional review board for this study, which included 42 patients, from all of whom written informed consent was obtained. Low-dose serial CT scanning after injection of 12 ml contrast material (300 mg/ml) at a rate of 3 ml/s followed by saline flush was performed twice, first at the level of the upper abdomen and second at the level of the knee joint. The times needed to reach peak enhancement of the upper abdominal aorta (T-aorta) and bilateral popliteal arteries (T-popliteal) were obtained, and aorto-popliteal bolus transit speeds between the abdominal aorta and popliteal arteries were calculated. ABI was recorded for the bilateral feet. The Pearson's product-moment correlation coefficient was used to investigate the correlation between the bolus transit speed and T-aorta, T-popliteal, ABI, and patient age. Result: The respective correlation coefficients for bolus transit speed on the one hand and T-aorta, T-popliteal, ABI, patient age on the other were -0.50, -0.84, 0.36, and -0.52. Conclusion: The time to peak enhancement for popliteal arteries showed the strongest correlation with aorto-popliteal bolus transit speeds, and was considered to be the most accurate predictor for aorto-popliteal bolus transit speeds.

  3. MO-H-19A-03: Patient Specific Bolus with 3D Printing Technology for Electron Radiotherapy

    Zou, W; Swann, B; Siderits, R; McKenna, M; Khan, A; Yue, N; Zhang, M [Rutgers University, New Brunswick, NJ (United States); Fisher, T [Memorial Medical Center, Modesto, CA (United States)

    2014-06-15

    Purpose: Bolus is widely used in electron radiotherapy to achieve desired dose distribution. 3D printing technologies provide clinicians with easy access to fabricate patient specific bolus accommodating patient body surface irregularities and tissue inhomogeneity. This study presents the design and the clinical workflow of 3D printed bolus for patient electron therapy in our clinic. Methods: Patient simulation CT images free of bolus were exported from treatment planning system (TPS) to an in-house developed software package. Bolus with known material properties was designed in the software package and then exported back to the TPS as a structure. Dose calculation was carried out to examine the coverage of the target. After satisfying dose distribution was achieved, the bolus structure was transferred in Standard Tessellation Language (STL) file format for the 3D printer to generate the machine codes for printing. Upon receiving printed bolus, a quick quality assurance was performed with patient resimulated with bolus in place to verify the bolus dosimetric property before treatment started. Results: A patient specific bolus for electron radiotherapy was designed and fabricated in Form 1 3D printer with methacrylate photopolymer resin. Satisfying dose distribution was achieved in patient with bolus setup. Treatment was successfully finished for one patient with the 3D printed bolus. Conclusion: The electron bolus fabrication with 3D printing technology was successfully implemented in clinic practice.

  4. MO-H-19A-03: Patient Specific Bolus with 3D Printing Technology for Electron Radiotherapy

    Purpose: Bolus is widely used in electron radiotherapy to achieve desired dose distribution. 3D printing technologies provide clinicians with easy access to fabricate patient specific bolus accommodating patient body surface irregularities and tissue inhomogeneity. This study presents the design and the clinical workflow of 3D printed bolus for patient electron therapy in our clinic. Methods: Patient simulation CT images free of bolus were exported from treatment planning system (TPS) to an in-house developed software package. Bolus with known material properties was designed in the software package and then exported back to the TPS as a structure. Dose calculation was carried out to examine the coverage of the target. After satisfying dose distribution was achieved, the bolus structure was transferred in Standard Tessellation Language (STL) file format for the 3D printer to generate the machine codes for printing. Upon receiving printed bolus, a quick quality assurance was performed with patient resimulated with bolus in place to verify the bolus dosimetric property before treatment started. Results: A patient specific bolus for electron radiotherapy was designed and fabricated in Form 1 3D printer with methacrylate photopolymer resin. Satisfying dose distribution was achieved in patient with bolus setup. Treatment was successfully finished for one patient with the 3D printed bolus. Conclusion: The electron bolus fabrication with 3D printing technology was successfully implemented in clinic practice

  5. Efficacy of bolus intravenous iron treatment in peritoneal dialysis patients

    Jovanović Nataša

    2005-01-01

    Full Text Available Introduction. Normocytic, normochromic anemia is one of the first signs of chronic renal failure and it is common in patients on chronic dialysis treatment. It causes decrease in oxygen supply to tissues, increases cardiac minute volume, causes left ventricular hyperthrophy, cardiac insufficiency, disorders related to cognitive functions and immune response, and increases morbidity and mortality rates. The leading cause of anemia in patients on chronic peritoneal dialysis (PD is iron depletion and most patients on PD need oral or parenteral iron supplementation. The aim of this study was to evaluate our first experience with bolus intravenous ferrogluconate therapy in patients on chronic peritoneal dialysis at the Nephrology Clinic of the Clinical Center of Serbia (CCS. Material and Methods. We examined 11 patients, 7 males and 4 females, mean-age 49 years (range 31 to 68 years on chronic PD. All patients received blood transfusions, oral or intramuscular iron supplementation before 465 to 665 mg ferrogluconate therapy was given in 500 ml. saline intravenous infusion; 5 of them were on erythropoietin therapy and 2 of them started with EPO therapy after the ferrogluconate therapy. Results. The blood count improved during the first 3 months after application of bolus intravenous iron therapy (ferrogluconate; erythropoietin dose was not increased during the follow-up. Some patients suffered from side effects during infusion and 6 patients received the complete treatment. Discussion. Blood count improves in a number of patients affected by end-stage renal disease during the first months on continuous ambulatory peritoneal dialysis (CAPD treatment. But a large number of patients on chronic CAPD treatment are iron-depleted and they require oral or parenteral substitution. Side effects and complications of intravenous iron therapy were not severe and only one patient suffered from allergic manifestations. Ferremia and blood count improved in patients

  6. A Bolus Calculator Based on Continuous-Discrete Unscented Kalman Filtering for Type 1 Diabetics

    Boiroux, Dimitri; Aradóttir, Tinna Björk; Hagdrup, Morten;

    2015-01-01

    after or 30 minutes after the beginning of the meal). We implement a continuous-discrete unscented Kalman filter to estimate the states and insulin sensitivity. These estimates are used in a bolus calculator. The numerical results demonstrate that administering the meal bolus 15 minutes after mealtime...

  7. Bolus dose with continuous infusion of midazolam as sedation for outpatient surgery.

    Luyk, N H; Zacharias, M; Wanwimolaruk, S

    1992-06-01

    This double-blind, randomised, cross-over trial in 41 patients for 3rd molar surgery compared the safety, amnesic properties and psychomotor recovery between a bolus injection of midazolam and a bolus injection followed by continuous infusion of midazolam. The latter showed good safety and better amnesia to events during the procedure, but prolonged the recovery time. PMID:1640130

  8. Split-bolus MR urography: synchronous visualization of obstructing vessels and collecting system in children

    Battal, Bilal; KOCAOĞLU, Murat; Akgün, Veysel; İnce, Selami; Gök, Faysal; Taşar, Mustafa

    2015-01-01

    Several vascular abnormalities related with urinary system such as crossing accessory renal vessels, retroiliac ureters, retrocaval ureters, posterior nutcracker syndrome, and ovarian vein syndrome may be responsible for urinary collecting system obstruction. Split-bolus magnetic resonance urography (MRU) using contrast material as two separate bolus injections provides superior demonstration of the collecting system and obstructing vascular anomalies simultaneously and enables accurate preop...

  9. Chelate chase of radiopharmaceuticals reversibly bound to monoclonal antibodies improves dosimetry

    One hundred micrograms of monoclonal antibody (MoAb) CHA 255 with a binding constant Kb of 4 x 109 was complexed with indium-111 labeled BLEDTA II, GLEDTA IV, benzyl EDTA, and an EDTA conjugate of Fab. The 24-hour tumor and organ distribution in BALB/c mice bearing KHJJ tumors was studied for each compound alone, the antibody complex, and 3 hours following a chelate chase of the antibody complex. Whole-body biological half-life was measured for 7 days with and without a chelate chase for each antibody complex. The 24-hour whole-body counts dropped 20-60% within 3 hours of administering the chelate chase. Blood concentration fell over 89% within 3 hours of administering the chase and there was a decrease in concentration in all organs, except the kidneys, of 10 to 85%. Theoretical equivalent human doses were calculated from the 24-hour organ concentrations, effective half-life, and MIRD 11 S values (absorbed dose per cumulated activity). Liver and spleen were the target organs, with the dose ranging from 0.50 to 3.91 rads per millicurie. The reduction in organ radiation dose varied up to 95% following the chelate chase. Rapid selective renal clearance of chelate labeled radiopharmaceuticals by competitive inhibition (chelate chase) of their reversible binding to monoclonal antibodies, greatly improves the radiation dosimetry of tumor imaging agents. 28 references, 5 figures, 5 tables

  10. Respostas fisiológicas de estresse no matrinxã (Brycon amazonicus após exercício físico intenso durante a captura Physiological stress responses of matrinxã (Brycon amazonicus after chasing

    Márcio Aquio Hoshiba

    2009-01-01

    Full Text Available Para determinar as respostas de estresse do matrinxã após perseguição com puçá, juvenis (26,7±6,7 g foram aclimatados em caixas plásticas e submetidos aos tratamentos: Controle (sem perseguição, Perseguição por 2 minutos, Perseguição por 5 minutos, Perseguição por 10 minutos (quatro repetições, N=8/tratamento. Amostras de sangue foram coletadas 15, 30 e 60 minutos após a perseguição para determinação do cortisol, glicose, sódio, cloreto, potássio, hematócrito, hemoglobina, número total de eritrócitos e osmolaridade. O perfil das respostas após o exercício físico dos peixes não mostrou as alterações típicas do estresse. Até 60 minutos após o estímulo, não ocorreram alterações nos níveis sanguíneos de cortisol, glicose e potássio nos peixes dos diferentes tratamentos. Os n��veis de cloreto foram reduzidos 15 minutos após a natação forçada, enquanto os níveis do sódio mais baixos foram registrados 60 minutos depois. Houve redução da osmolaridade a partir dos 30 minutos após o estímulo, independente do tempo de perseguição. A natação forçada não interferiu nos indicadores hematológicos, corroborando os outros indicadores usados. Dessa forma, o exercício intenso dos peixes por até 10 minutos não foi estímulo suficiente para gerar respostas de estresse, sugerindo que o matrinxã é bastante resistente ao manejo de criação.This study reports the stress responses of matrinxã after chasing. Juvenile fish (26.7±6.7 g were adapted to 100L plastic boxes and submitted to the treatments: Control (no chasing, Chasing for 2 min, Chasing for 5 min, Chasing for 10 min (four boxes/treatment, 32 fish. Blood was drawn 15, 30 and 60 min after chasing to determine levels of cortisol, glucose, sodium, chloride, potassium, calcium, hematocrit, hemoglobin, erythrocytes number and osmolality. Matrinxã responses after forced swimming did not show the typical stress responses. There were no changes in

  11. Very rapid bolus injection as routine method in excretion urography

    Weigert, F.; Wehweck, H.; Eggemann, F.

    1982-09-01

    The authors report on a comparative examination of the tolerance and diagnostic value of excretion urography using a standard dose of 50 ml of a 77% solution of the meglumine-sodium salt of ioxythalamic acid (Telebrix 380) at conventional injection speed (60-90 sec.) compared with a very rapid bolus injection (less than 10 sec.) Although the risk of severe side effects is probably the same in both cases, the rate of mild or so-called non-specific side effects is significantly lower with the more rapid type of injection. At the same time, it is possible to improve the diagnostic value with a slightly greater effort (vascular early nephrogram.

  12. Very rapid bolus injection as routine method in excretion urography

    The authors report on a comparative examination of the tolerance and diagnostic value of excretion urography using a standard dose of 50 ml of a 77% solution of the meglumine-sodium salt of ioxythalamic acid (Telebrix 380) at conventional injection speed (60-90 sec.) compared with a very rapid bolus injection (less than 10 sec.) Although the risk of severe side effects is probably the same in both cases, the rate of mild or so-called non-specific side effects is significantly lower with the more rapid type of injection. At the same time, it is possible to improve the diagnostic value with a slightly greater effort (vascular early nephrogram. (orig.)

  13. Dispersion of a nanoliter bolus in microfluidic co-flow

    Microfluidic systems enable reactions and assays on the scale of nanoliters. However, at this scale non-uniformities in sample delivery become significant. To determine the fundamental minimum sample volume required for a particular device, a detailed understanding of mass transport is required. Co-flowing laminar streams are widely used in many devices, but typically only in the steady-state. Because establishing the co-flow steady-state consumes excess sample volume and time, there is a benefit to operating devices in the transient state, which predominates as the volume of the co-flow reactor decreases. Analysis of the co-flow transient has been neglected thus far. In this work we describe the fabrication of a pneumatically controlled microfluidic injector constructed to inject a discrete 50 nL bolus into one side of a two-stream co-flow reactor. Using dye for image analysis, injections were performed at a range of flow rates from 0.5–10 µL min−1, and for comparison we collected the co-flow steady-state data for this range. The results of the image analysis were also compared against theory and simulations for device validation. For evaluation, we established a metric that indicates how well the mass distribution in the bolus injection approximates steady-state co-flow. Using such analysis, transient-state injections can approximate steady-state conditions within pre-defined errors, allowing straightforward measurements to be performed with reduced reagent consumption. (paper)

  14. Chasing Venus: Putting the Transits of Venus on Exhibition

    Brashear, R. S.

    2003-12-01

    The upcoming 2004 transit of Venus provides a great opportunity to develop programs to educate the public about the history of the observations of the transits. The Smithsonian Institution Libraries is well-placed to take part in this effort with its collection of rare books that deal with the 17th- and 18th-century transits. The exhibition called ``Chasing Venus" will be on display at the National Museum of American History, Behring Center, from March 2004 to April 2005. The Museum will loan a number of its 19th-century artifacts and the US Naval Observatory is also cooperating with the loan of a telescope and some rare books from the USNO Library to flesh out the story of the 19th-century transits. The talk will take a closer look at the books and artifacts that will be used to tell the history of the transit observations in the special context of a library exhibition. Books from a wide variety of authors such as Kepler, Horrocks, Capt. Cook, Rittenhouse, Mason & Dixon, and even John Philip Sousa (!) will help express the authors' excitement about the event to the public at large.

  15. 'Chasing the Dragon' - imaging of heroin inhalation leukoencephalopathy

    'Chasing the dragon' refers to the inhalation of heroin pyrolysate vapors produced when the freebase form of heroin is heated. Inhalation of these vapors can result in a rare toxic spongiform leukoencephalopathy. The patients may progress through 3 defined clinical stages, with one-quarter reaching the terminal stage, which invariably leads to death. Imaging and, in particular, magnetic resonance imaging (MRI) demonstrates white matter findings that are felt to be specific for this entity and essential in its early diagnosis. We present the typical imaging findings in a pictorial essay format, using images taken from 9 patients who presented within an 18-month period at UBC-affiliated hospitals. These findings include low computed tomography (CT) attenuation and high T2 MRI signal most commonly in the posterior cerebral and cerebellar white matter, cerebellar peduncles, splenium of the corpus callosum, and posterior limb of the internal capsules. In addition, there is often selective, symmetric involvement of the corticospinal tract, the medial lemniscus, and the tractus solitarius. We also present the variable diffusion-weighted imaging arid apparent diffusion coefficient findings from 4 of our patients, which to our knowledge, have not been described in the literature. (author)

  16. Patterns of Light Chasing the Spectrum from Aristotle to LEDs

    Beeson, Steven

    2008-01-01

    Light is all around us – even when we do not see it. Our eyes do not detect the higher energy and shorter-than-visible-wavelength ultraviolet radiation, yet we know it is there from the sunburn we receive in Arizona. We know that window glass can block ultraviolet rays so we do not get a burn while driving with the windows rolled up. Our eyes do not detect the low-energy, long-wavelength infrared (IR) radiation but we know it exists from discussions of war applications and televised images of guided weapons targets. We also know about radio waves from the little boxes that talk to us and x-rays from the dentist's office. Patterns of Light, Chasing the Spectrum from Aristotle to LEDs, written by Steve Beeson and Jim Mayer starts with the visible – the straight path of light. It continues with chapters detailing reflection (mirrors, storefront windows) and refraction (eyeglasses, binoculars). Color is then introduced with the query "Why is the sky blue?" After answering that and other similar questions ("Wh...

  17. Correlation of esophageal pressure-flow analysis findings with bolus transit patterns on videofluoroscopy.

    Omari, T I; Szczesniak, M M; Maclean, J; Myers, J C; Rommel, N; Cock, C; Cook, I J

    2016-01-01

    Pressure-flow analysis quantifies the interactions between bolus transport and pressure generation. We undertook a pilot study to assess the interrelationships between pressure-flow metrics and fluoroscopically determined bolus clearance and bolus transport across the esophagogastric junction (EGJ). We hypothesized that findings of abnormal pressure-flow metrics would correlate with impaired bolus clearance and reduced flow across the EGJ. Videofluoroscopic images, impedance, and pressure were recorded simultaneously in nine patients with dysphagia (62-82 years, seven male) tested with liquid barium boluses. A 3.6 mm diameter solid-state catheter with 25 × 1 cm pressure/12 × 2 cm impedance was utilized. Swallowed bolus clearance was assessed using a validated 7-point radiological bolus transport scale. The cumulative period of bolus flow across the EGJ was also fluoroscopically measured (EGJ flow time). Pressure only parameters included the length of breaks in the 20 mmHg iso-contour and the 4 second integrated EGJ relaxation pressure (IRP4s). Pressure-flow metrics were calculated for the distal esophagus, these were: time from nadir impedance to peak pressure (TNadImp to PeakP) to quantify bolus flow timing; pressure flow index (PFI) to integrate bolus pressurization and flow timing; and impedance ratio (IR) to assess bolus clearance. When compared with controls, patients had longer peristaltic breaks, higher IRs, and higher residual EGJ relaxation pressures (break length of 8 [2, 13] vs. 2 [0, 2] cm, P = 0.027; IR 0.5 ± 0.1 vs. 0.3 ± 0.0, P = 0.019; IRP4s 11 ± 2 vs. 6 ± 1 mmHg, P = 0.070). There was a significant positive correlation between higher bolus transport scores and longer peristaltic breaks (Spearman correlation r = 0.895, P times correlated with a shorter TNadImp to PeakP (r = -0.733, P metric TNadImp to PeakP appears to be a marker of the period of time over which the bolus flows across the EGJ. PMID:25515292

  18. The comparison of bolus tracking and test bolus techniques for computed tomography thoracic angiography in healthy beagles

    Nicolette Cassel

    2013-02-01

    Full Text Available Computed tomography thoracic angiography studies were performed on five adult beagles using the bolus tracking (BT technique and the test bolus (TB technique, which were performed at least two weeks apart. For the BT technique, 2 mL/kg of 300 mgI/mL iodinated contrast agent was injected intravenously. Scans were initiated when the contrast in the aorta reached 150 Hounsfield units (HU. For the TB technique, the dogs received a test dose of 15% of 2 mL/kg of 300 mgI/mL iodinated contrast agent, followed by a series of low dose sequential scans. The full dose of the contrast agent was then administered and the scans were conducted at optimal times as identified from time attenuation curves. Mean attenuation in HU was measured in the aorta (Ao and right caudal pulmonary artery (rCPA. Additional observations included the study duration, milliAmpere (mA, computed tomography dose index volume (CTDI[vol] and dose length product (DLP. The attenuation in the Ao (BT = 660 52 HU ± 138 49 HU, TB = 469 82 HU ± 199 52 HU, p = 0.13 and in the rCPA (BT = 606 34 HU ± 143 37 HU, TB = 413 72 HU ± 174.99 HU, p = 0.28 did not differ significantly between the two techniques. The BT technique was conducted in a significantly shorter time period than the TB technique (p = 0.03. The mean mA for the BT technique was significantly lower than the TB technique (p = 0.03, as was the mean CTDI(vol (p = 0.001. The mean DLP did not differ significantly between the two techniques (p = 0.17. No preference was given to either technique when evaluating the Ao or rCPA but the BT technique was shown to be shorter in duration and resulted in less DLP than the TB technique.

  19. The use of Coca-Cola in the management of bolus obstruction in benign oesophageal stricture.

    Karanjia, N D; Rees, M

    1993-03-01

    Oesophageal stricture is a complication of oesophageal reflux and may itself be complicated by bolus obstruction. We reviewed the records of patients presenting with dysphagia and who were found to have benign oesophageal strictures. We studied the outcome of bolus obstruction in 13 episodes affecting eight patients. In six episodes Coca-Cola was administered on the day before endoscopy, and in all these patients the bolus had cleared. In seven episodes nothing was administered before endoscopy, and in all seven a bolus was evident at endoscopy. In five of these seven the bolus was removed piecemeal and in each of these instances the endoscope had to be passed between two and five times. In the remaining two instances the procedure was abandoned and the patients returned to the ward for the administration of Coca-Cola. At subsequent endoscopy these patients were found to be clear of any bolus. These results suggest that the administration of Coca-Cola (or other aerated drinks) may clear a bolus in the acutely obstructed oesophagus. PMID:8476194

  20. Efficacy study of Styplon Vet Bolus as supportive therapy in management of hemorrhagic conditions of ruminants

    B R Ravikumar

    Full Text Available On-field trial was conducted in dairy animals to evaluate efficacy of Styplon Vet Bolus (M/s Himalaya Drug Company, Banglore, India as supportive therapy in management of hemorrhagic conditions (Hematuria, hemoagalectia, bleeding wounds, uterine bleeding and epistaxis of ruminants. Styplon Vet 1-2 boli twice daily was administered to cows and buffaloes, and ½ bolus twice daily for sheep till they recover clinically. The results indicated that Styplon Vet Bolus is a safe and effective styptic in ruminants. [Vet World 2009; 2(12.000: 470-471

  1. Intravenous ranitidine: Rapid bolus can lead to cardiac arrest

    Kamlesh J Upadhyay

    2015-01-01

    Full Text Available This is a rare case report of a 30-year-old male, who was admitted to the Maxillofacial Surgery Department of the Dental College for a malunited fracture of the mandible and zygomatic bones. He was given oral medications namely, cefixime, metronidazole, ondansetron, and ranitidine for three days prior to the operation with complete normal preoperative workup. He had no significant past medical or family history. On the day of the operation, he was given injectable dexamethasone, cefotaxime, ondansetron, ranitidine, and metronidazole half-an-hour prior to the operation. In less than five minutes of giving a bolus ranitidine injection, the patient developed a cardiac arrest and was resuscitated by the anesthetist team on duty. He was transferred to the Intensive Care Unit (ICU on a ventilator, which was soon removed and the patient was off vasopressors, with stable vitals for 24 hours after the event. He was then transferred to the general ward of Medicine Department and observed for a further two days during which the patient remained uneventful and was finally transferred back to the Dental Department.

  2. Intravenous ranitidine: Rapid bolus can lead to cardiac arrest.

    Upadhyay, Kamlesh J; Parmar, Sarita J; Parikh, Rohan Pravinbhai; Gauswami, Prashant K; Dadhaniya, Nikunj; Surela, Abhilash

    2015-01-01

    This is a rare case report of a 30-year-old male, who was admitted to the Maxillofacial Surgery Department of the Dental College for a malunited fracture of the mandible and zygomatic bones. He was given oral medications namely, cefixime, metronidazole, ondansetron, and ranitidine for three days prior to the operation with complete normal preoperative workup. He had no significant past medical or family history. On the day of the operation, he was given injectable dexamethasone, cefotaxime, ondansetron, ranitidine, and metronidazole half-an-hour prior to the operation. In less than five minutes of giving a bolus ranitidine injection, the patient developed a cardiac arrest and was resuscitated by the anesthetist team on duty. He was transferred to the Intensive Care Unit (ICU) on a ventilator, which was soon removed and the patient was off vasopressors, with stable vitals for 24 hours after the event. He was then transferred to the general ward of Medicine Department and observed for a further two days during which the patient remained uneventful and was finally transferred back to the Dental Department. PMID:25969659

  3. Intravenous ranitidine: Rapid bolus can lead to cardiac arrest

    Upadhyay, Kamlesh J; Parmar, Sarita J; Parikh, Rohan Pravinbhai; Gauswami, Prashant K; Dadhaniya, Nikunj; Surela, Abhilash

    2015-01-01

    This is a rare case report of a 30-year-old male, who was admitted to the Maxillofacial Surgery Department of the Dental College for a malunited fracture of the mandible and zygomatic bones. He was given oral medications namely, cefixime, metronidazole, ondansetron, and ranitidine for three days prior to the operation with complete normal preoperative workup. He had no significant past medical or family history. On the day of the operation, he was given injectable dexamethasone, cefotaxime, ondansetron, ranitidine, and metronidazole half-an-hour prior to the operation. In less than five minutes of giving a bolus ranitidine injection, the patient developed a cardiac arrest and was resuscitated by the anesthetist team on duty. He was transferred to the Intensive Care Unit (ICU) on a ventilator, which was soon removed and the patient was off vasopressors, with stable vitals for 24 hours after the event. He was then transferred to the general ward of Medicine Department and observed for a further two days during which the patient remained uneventful and was finally transferred back to the Dental Department. PMID:25969659

  4. The rapid-chase theory does not extend to movement execution.

    Flannigan, Jenna C; Chua, Romeo; Cressman, Erin K

    2016-05-01

    It is assumed that the processing of a prime followed by a mask occurs sequentially in a feedforward manner when the three (initiation, takeover, and independence) criteria outlined by the rapid-chase theory are met. The purpose of the current study was to determine if the processing of the prime and mask fit the predictions of the rapid-chase theory when the prime and mask are presented during an ongoing movement. In two experiments, participants made rapid pointing movements to a target indicated by the mask. In Experiment 1, the prime was presented at movement onset and the prime-mask stimulus onset asynchrony (SOA) was manipulated. In Experiment 2, the prime-mask SOA was constant but the delay between movement and prime onset was manipulated. Although the results support the initiation and takeover criteria, the data did not support the independence criterion. Consequently, the rapid-chase theory does not appear to extend to movement execution. PMID:26998560

  5. INDUCED SPUTUM DERIVES FROM THE CENTRAL AIRWAYS: CONFIRMATION USING A RADIOLABELED AEROSOL BOLUS DELIVERY TECHNIQUE

    Indirect evidence suggests that induced sputum derives from the surfaces of the bronchial airways. To confirm this experimentally, we employed a radiolabeled aerosol bolus delivery technique that preferentially deposits aerosol in the central airways in humans. We hypothesized th...

  6. The Effects of Bolus Consistency in Pharyngeal Transit Duration during Normal Swallowing

    Im, Ikjae; Kim, Youngsun; Oommen, Elizabeth; Kim, Hyungi; Ko, Myoung Hwan

    2012-01-01

    Objective To examine the effects of age, gender and bolus consistency in normal populations using the temporal measurement of Pharyngeal Transit Duration (PTD), which reflects the duration of bolus flow from the ramus of the mandible to the upper esophageal sphincter. Method 40 normal and healthy subjects had Videofluoroscopic Swallowing Examinations (VFSEs) of 5 ml thin and nectar thick liquids, and puree consistencies. A slow motion and frame by frame analysis was performed. Three-way analy...

  7. Causes of death after fluid bolus resuscitation: new insights from FEAST

    Myburgh, John; Finfer, Simon

    2013-01-01

    The Fluid Expansion as Supportive Therapy (FEAST study) was an extremely well conducted study that gave unexpected results. The investigators had reported that febrile children with impaired perfusion treated in low-income countries without access to intensive care are more likely to die if they receive bolus resuscitation with albumin or saline compared with no bolus resuscitation at all. In a secondary analysis of the trial, published in BMC Medicine, the authors found that increased mortal...

  8. The effect of food bolus location on jaw movement smoothness and masticatory efficiency

    Molenaar, W N B; Gezelle Meerburg, P J; Luraschi, Julien; Whittle, T; Schimmel, Martin; Lobbezoo, F; Peck, C C; Murray, G. M.; Minami, I

    2012-01-01

    Masticatory efficiency in individuals with extensive tooth loss has been widely discussed. However, little is known about jaw movement smoothness during chewing and the effect of differences in food bolus location on movement smoothness and masticatory efficiency. The aim of this study was to determine whether experimental differences in food bolus location (anterior versus posterior) had an effect on masticatory efficiency and jaw movement smoothness. Jaw movement smoothness was evaluated by...

  9. GammeV and GammeV-CHASE

    Wester, W.; /Fermilab

    2011-11-01

    Physics beyond the Standard Model might include Weakly Interacting Slim Particles (WISPs) that address questions such as what is the nature of dark matter or even shed insight into the underlying nature of dark energy. WISPs are a general class of particles that include axions, axion-like particles, hidden sector photons, milli-charged particles, chameleons, etc. The GammeV (Gamma to milli-eV) experiment originated in 2007 in order to test a positive anomalous axion-like particle interpretation of the PVLAS experiment which was not evident in subsequent data. The experiment was also motivated as it was realized that the milli-eV scale appears naturally in a see-saw between the electroweak and Planck scales, neutrino mass differences, the dark energy density, and the possible mass for certain dark matter candidates. GammeV was first to exclude both a scalar and pseudoscalar axion-like particle interpretation of the anomalous PVLAS result setting a limit of around 3.1 x 10{sup -7} GeV{sup -1} on the coupling to photons for low mass axion-like particles. It has also been found that the parameter space of a variety of other WISP candidates is both largely unexplored and is accessible by modest experiments employing lasers and possibly accelerator magnets. GammeV data has also been used to set limits on possible hidden sector photons. Further work by the GammeV team has focused on a reconfiguration of the apparatus to be sensitive to possible chameleon particles. Chameleons are scalar (or pseudoscalar) particles that couple to the stress energy tensor in a potential such that their properties depend on their environment. In particular, a chameleon acquires an effective mass which increases with local matter density, {rho}. For a certain class of such potentials, the chameleon field has properties that might explain dark energy. GammeV set the first limits on the coupling of chameleons to photons. A dedicated follow-up experiment, GammeV-CHASE, (CHameleon Afterglow

  10. GammeV and GammeV-CHASE

    Physics beyond the Standard Model might include Weakly Interacting Slim Particles (WISPs) that address questions such as what is the nature of dark matter or even shed insight into the underlying nature of dark energy. WISPs are a general class of particles that include axions, axion-like particles, hidden sector photons, milli-charged particles, chameleons, etc. The GammeV (Gamma to milli-eV) experiment originated in 2007 in order to test a positive anomalous axion-like particle interpretation of the PVLAS experiment which was not evident in subsequent data. The experiment was also motivated as it was realized that the milli-eV scale appears naturally in a see-saw between the electroweak and Planck scales, neutrino mass differences, the dark energy density, and the possible mass for certain dark matter candidates. GammeV was first to exclude both a scalar and pseudoscalar axion-like particle interpretation of the anomalous PVLAS result setting a limit of around 3.1 x 10-7 GeV-1 on the coupling to photons for low mass axion-like particles. It has also been found that the parameter space of a variety of other WISP candidates is both largely unexplored and is accessible by modest experiments employing lasers and possibly accelerator magnets. GammeV data has also been used to set limits on possible hidden sector photons. Further work by the GammeV team has focused on a reconfiguration of the apparatus to be sensitive to possible chameleon particles. Chameleons are scalar (or pseudoscalar) particles that couple to the stress energy tensor in a potential such that their properties depend on their environment. In particular, a chameleon acquires an effective mass which increases with local matter density, ρ. For a certain class of such potentials, the chameleon field has properties that might explain dark energy. GammeV set the first limits on the coupling of chameleons to photons. A dedicated follow-up experiment, GammeV-CHASE, (CHameleon Afterglow SEarch), has also

  11. Clinical Study Double Bolus Application in TWIST-MR-Angiography of the Cervical Arteries

    Purpose. The aim of the present work was to test the feasibility of the time-resolved MR-angiography (TWIST-MRA) of cervical arteries using double bolus injection. Material and Methods. TWIST-MRA with a temporal resolution of 8.4 seconds for each frame and a spatial resolution with a voxel size of 0.61 × 0.58 × 0.8 mm3 was performed in 24 patients. A biphasic bolus injection protocol was used with the second injection being started 21 seconds after the first contrast dye bolus. Diagnostic image quality was rated according to a 4-point scale. Results. In 12 patients (50%) no clear separation between the cervical venous and arterial vessels was evident after the first bolus injection. Using TWIST-MRA data acquired after the second bolus a sufficient diagnostic image quality (rating ≥ 3 , mean 3.5) could be obtained in 22 of 24 patients (92%). Discussion. The double bolus injection protocol using TWIST-MRA allows for very good separation of the cervical arteries

  12. Pressure Flow Analysis in the Assessment of Preswallow Pharyngeal Bolus Presence in Dysphagia

    Lara Ferris

    2015-01-01

    Full Text Available Objectives. Preswallow pharyngeal bolus presence is evident in patients with oropharyngeal dysphagia. Pressure flow analysis (PFA using high resolution manometry with impedance (HRMI with AIMplot software is a method for objective interpretation of pharyngeal and upper esophageal sphincter (UES pressures and bolus flow patterns during swallowing. This study aimed to observe alterations in PFA metrics in the event of preswallow pharyngeal bolus presence as seen on videofluoroscopy (VFSS. Methods. Swallows from 40 broad dysphagia patients and 8 controls were recorded with a HRMI catheter during simultaneous VFSS. Evidence of bolus presence and level reached prior to pharyngeal swallow onset was recorded. AIMPlot software derived automated PFA functional metrics. Results. Patients with bolus movement to the pyriform sinuses had a higher SRI, indicating greater swallow dysfunction. Amongst individual metrics, TNadImp to PeakP was shorter and flow interval longer in patient groups compared to controls. A higher pharyngeal mean impedance and UES mean impedance differentiated the two patient groups. Conclusions. This pilot study identifies specific altered PFA metrics in patients demonstrating preswallow pharyngeal bolus presence to the pyriform sinuses. PFA metrics may be used to guide diagnosis and treatment of patients with oropharyngeal dysphagia and track changes in swallow function over time.

  13. Effect of oral calcium bolus supplementation on early-lactation health and milk yield in commercial dairy herds.

    Oetzel, G R; Miller, B E

    2012-12-01

    The objective of this study was to evaluate the effect of supplementation with oral Ca boluses after calving on early-lactation health and milk yield. Cows in their second lactation or greater (n=927) from 2 large dairies in Wisconsin were enrolled during the summer of 2010. Both herds were fed supplemental anions during the prefresh period and less than 1% of fresh cows were treated for clinical milk fever. Cows were scored before calving for lameness and body condition, and then randomly assigned to either a control group or an oral Ca bolus-supplemented group. Control cows received no oral Ca boluses around calving. Cows in the oral Ca bolus group received 2 oral Ca boluses (Bovikalc, Boehringer Ingelheim, St. Joseph, MO), one bolus 0 to 2h after calving and the second 8 to 35 h after calving. The oral Ca bolus administration schedule allowed fresh cows to be restrained in headlocks only once daily. Whole-blood samples were collected immediately before the second oral Ca bolus was given and were analyzed for ionized Ca (Ca(2+)) concentration. Early-lactation health events were recorded and summed for each cow. Only 6 cases (0.6% of calvings) of clinical milk fever occurred during the trial, and only 14% of cows tested were hypocalcemic (Ca(2+) less than 1.0 mmol/L) at 8 to 35 h after calving. Mean Ca(2+) concentrations were not different between the control and oral Ca bolus-supplemented groups. Blood samples from the cows given oral Ca boluses were collected an average of 20.6 h after administration of the first bolus. Subpopulations of cows with significant responses to oral Ca bolus supplementation were identified based on significant interactions between oral Ca bolus supplementation and covariates in mixed multiple regression models. Lame cows supplemented with oral Ca boluses averaged 0.34 fewer health events in the first 30 d in milk compared with lame cows that were not supplemented with oral Ca boluses. Cows with a higher previous lactation mature

  14. Kinetic analysis of the metabotropic glutamate subtype 5 tracer [(18)F]FPEB in bolus and bolus-plus-constant-infusion studies in humans.

    Sullivan, Jenna M; Lim, Keunpoong; Labaree, David; Lin, Shu-Fei; McCarthy, Timothy J; Seibyl, John P; Tamagnan, Gilles; Huang, Yiyun; Carson, Richard E; Ding, Yu-Shin; Morris, Evan D

    2013-04-01

    [(18)F]FPEB is a positron emission tomography tracer which, in preclinical studies, has shown high specificity and selectivity toward the metabotropic glutamate receptor 5 (mGluR5). It possesses the potential to be used in human studies to evaluate mGluR5 function in a range of neuropsychiatric disorders, such as anxiety and Fragile X syndrome. To define optimal scan methodology, healthy human subjects were scanned for 6 hours following either a bolus injection (n=5) or bolus-plus-constant-infusion (n=5) of [(18)F]FPEB. Arterial blood samples were collected and parent fraction measured by high-performance liquid chromatography (HPLC) to determine the metabolite-corrected plasma input function. Time activity curves were extracted from 13 regions and fitted by various models to estimate V(T) and BPND. [(18)F]FPEB was well fitted by the two-tissue compartment model, MA1 (t*=30), and MRTM (using cerebellum white matter as a reference). Highest V(T) values were observed in the anterior cingulate and caudate, and lowest V(T) values were observed in the cerebellum and pallidum. For kinetic modeling studies, VT and BPND were estimated from bolus or bolus-plus-constant-infusion scans as short as 90 minutes. Bolus-plus-constant-infusion of [(18)F]FPEB reduced intersubject variability in V(T) and allowed equilibrium analysis to be completed with a 30-minute scan, acquired 90-120 minutes after the start of injection. PMID:23250105

  15. Cineradiography of the liquid bolus swallow. A study of the speed ot the bolus and peristaltic wave and of movement of the hyoid bone, larynx, and epiglottis

    In the evaluation of the dysphagic patient, radiology is crucial as a technique for monitoring morphology and function. In particular, high-speed cineradiography can reveal a variety of pharyngeal dysfunctions. However, in the literature and in practice the difference between normal and abnormal function is not always clear. This monography is based on high-speed cineradiographies of swallowing in 75 non-dysphagic volunteers and in 189 dysphagic patients. The purpose was to study whether differences in bolus volumes, patient position, age and gender had any effects on the following parameters: the speed of the peristaltic wave and apex of the liquid barium bolus, the length of movement and the movement pattern of the hyoid bone and larynx, and epiglottic function. The study disclosed that the speed of the bolus, the anterior-superior movement and net movement of the hyoid bone increased significantly with larger bolus volumes. The position of the individual in relation to gravity significantly influenced the speed of peristalsis. In most of the measured parameters there were no differences between non-dysphagic and dysphagic individuals expect for differences in the intrapersonal variations and in the anterior-superior movement of the hyoid bone. In patients with pharyngeal dysfunction the initial stage of the elevation of the larynx was significantly lower than in patients without dysfunction. The approximation of the thyroid cartilage to the hyoid bone was significantly greater in individuals with normal epiglottic function than in those with epiglottic dysmobility. It is suggested that abnormal speed of peristalsis may be a mild form of dysfunction. Measurements of the aforementioned speed and movements can be done if bolus volume, age and position of the patient, film speed and magnifications factors are known. Hypotheses concerning epiglottic function and central control of swallowing are proposed. (au)

  16. 76 FR 58805 - Notice of Availability of Environmental Assessment; Jonathan and Jayne Chase

    2011-09-22

    ... Commission's regulations, 18 CFR Part 380 (Order No. 486, 52 FR 47879), the Office of Energy Projects has... Energy Regulatory Commission Notice of Availability of Environmental Assessment; Jonathan and Jayne Chase... Commission strongly encourages electronic filing, documents may also be paper-filed. To paper-file, mail...

  17. Inquiring into "Techniques of Power" with Preservice Teachers through the "School Film""The Paper Chase."

    Trier, James

    2003-01-01

    Describes a project in which a cohort of preservice teachers engaged in an inquiry into techniques of power, focusing on the power relations between teachers and students. The project analyzed the film, "The Paper Chase" and articulated eight techniques of power and certain elements from Foucault's "Discipline and Punish." The article explains how…

  18. Search Characteristics and the Effects of Experience on End Users of PaperChase.

    King, Natalie Schoch

    1991-01-01

    Reports on a study that examined transaction logs of end users of PaperChase searching UM-MEDLINE at the University of Michigan to describe the use of various search features and to determine the effects of search experience on the use of search features. Boolean operators are discussed, and further studies are suggested. (23 references) (LRW)

  19. Dual bolus intravenous contrast injection technique for multiregion paediatric body CT

    Thomas, Karen E.; Mann, E.H.; Padfield, N.; Greco, L.; BenDavid, G. [The Hospital for Sick Children, Department of Diagnostic Imaging, Toronto (Canada); Alzahrani, A. [King Abdulaziz Medical City, PO Box 22490, Riyadh (Saudi Arabia)

    2015-04-01

    Optimal vascular and parenchymal enhancement for multi-region paediatric body computed tomography (CT) has many challenges. A variety of approaches are currently employed, associated with varying image quality and radiation dose implications. We present a dual bolus intravenous (DBI) contrast technique for single-acquisition imaging of the chest, abdomen and pelvis, with evaluation of multi-compartmental vascular enhancement. A DBI regime was designed for use with a programmable dual head pump injector. A larger initial bolus (two-thirds volume) is followed by a smaller bolus (one-third volume) before imaging the chest, abdomen and pelvis in a single acquisition, 45-65 seconds from the start of initial injection. Flow rates and second bolus timing were tailored to patient weight and contrast volume, using five weight categories. Multi-compartmental vascular opacification was graded and image quality was assessed in a cohort of 130 patients. The DBI technique resulted in concordant multi-compartmental (thoracic aortic, pulmonary arterial, abdominal aortic and portal venous) vascular enhancement. Early splenic parenchymal enhancement artefacts and alterations to renal enhancement were observed. We present a weight-stratified dual bolus intravenous contrast technique to improve image quality in paediatric multi-region body CT. (orig.)

  20. Effects of copper oxide wire particle bolus therapy on trichostrongyle fecal egg counts in exotic artiodactylids.

    Fontenot, Deidre K; Kinney-Moscona, Allyson; Kaplan, Ray M; Miller, James

    2008-12-01

    Four species of artiodactylids (scimitar-horned oryx [Oryx dama]), roan antelope [Hippotragus equinus], blackbuck [Antilope cervicapra]), and blesbok [Damaliscus pygargus phillipsi]) totaling 13 animals were treated with a one-time 12.5-g dose of copper oxide wire particles (COWPs) in a bolus form. Pretreatment, individual trichostrongyle fecal egg counts (FECs) were performed using the McMaster technique. Individual posttreatment FECs were performed every 7 days for 35 days beginning 7 days after bolus administration, and FEC reduction ratios (FECRRs) expressed as percentage reductions from pretreatment values were calculated every 7 days. Mean FECRRs for the 13 animals were 93% +/- 16%, 98% +/- 7%, 91% +/- 28%, 94% +/- 16%, and 90% +/- 13% at 7, 14, 21, 28, and 35 days posttreatment, respectively. These data demonstrate that COWPs in a bolus form were an effective method for reducing FEC in exotic artiodactylids. Based on this limited data, COWPs show promise as an anthelmintic alternative for exotic artiodactylids in zoologic collections. PMID:19110710

  1. Development of a water bolus for high-energy radiation therapy

    A sheet-type bolus has been developed and is used in Japan for hyperthermia treatment. This sheet substance is made from water (89%) and high-polymer absorbant (11%). Its density is 1.03 g/cm3. The authors tested the quantitative and qualitative character of this substance as a bolus for radiation therapy. The substance is transparent, flexible, nontoxic, and odorless, can be conformed well to human surface contours, and can be easily cut in any size. Dosimetry data are equivalent to human tissue phantoms and have been obtained with a Farmer-type chamber. This sheet was found to be very useful as a bolus material for radiation therapy

  2. A shredded-gel bolus material for use with an EMI CT1010 brain scanner

    Packing has to be applied around a patient's head prior to scanning, and the thin rubber, powder-filled bolus bags supplied by EMI have several shortcomings which are responsible for artefacts in CT examinations of young children and babies. A description is given of a new bolus material consisting of a shredded mix of water, gelatin, ethanol and a bacteriostatic agent. Tests have shown that bags containing this material gave accurate CT scans for these patients using the standard EMI CT1010 system. The gelatin-based packing is cheaper and more convenient in use than several EMI bolus bags used either alone or in conjunction with small field carbon wedges for these small heads. (UK)

  3. Advantages of the intravenous bolus CT scan in differentiation of hepatic masses

    We performed IV bolus CT scan in 40 patients with final diagnosis of various hepatic masses in order to evaluate hemodynamic changes and differentiating characters of the lesions. Preenhanced, early and late phase post enhanced, and delayed CT scans were obtained with rapid IV bolus injection of contrast materials and table sliding method for pertinent scans. In hepatomas, early enhanced CT scan directly showed hypervascular change and active viable portion of the mass and late phase CT scan showed capsular enhancement. In addition, extracapsular invasion and post-embolization recurrence were more easily visualized. In hemangiomas, early and late enhancing types could be categorized according to the time of maximal enhancement. In metastatic liver malignancies and cholangiocarcinomas, specific findings were seen in early phase and delayed CT scans and not in conventional CT scan. In conclusion, IV bolus CT scan is a very useful CT method in demonstrating the characteristic hemodynamic patterns and in differential diagnosis of the hepatic masses

  4. Oral and pharyngeal bolus transit in patients with chronic obstructive pulmonary disease

    Cassiani RA

    2015-03-01

    Full Text Available Rachel Aguiar Cassiani, Carla Manfredi Santos, José Baddini-Martinez, Roberto Oliveira Dantas Department of Medicine, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil Background: Patients with respiratory diseases, such as chronic obstructive pulmonary disease (COPD, may have swallowing dysfunction. Objective: The aim of this investigation was to evaluate the oral and pharyngeal phases of swallowing in patients with COPD. Methods: We studied 16 patients with clinical manifestations and pulmonary function tests diagnosis of COPD (mean age: 68 years and 15 nonsmoking healthy volunteers (mean age: 65 years with normal pulmonary function tests. All subjects were submitted to clinical and videofluoroscopic evaluation of swallowing. Each subject performed in duplicate swallows of 5 mL and 10 mL of liquid bolus, paste bolus, and a solid bolus. Results: In general, the duration of the events of the pharyngeal phase of swallowing was longer in COPD patients than controls. The difference was significant in the laryngeal vestibular closure, hyoid movement, and pharyngeal transit with swallows of both volumes of liquid bolus; in oral–pharyngeal transit with 5 mL paste bolus; and in pharyngeal and oral–pharyngeal transit with solid bolus. The difference between the duration of maximal laryngeal elevation and the duration of pharyngeal transit was higher in control subjects than in patients with COPD. Conclusion: The results suggested that patients with COPD have a longer pharyngeal swallowing phase than normal subjects, which is associated with a decrease in the difference between the duration of maximal laryngeal elevation and the duration of pharyngeal transit. Keywords: COPD, videofluoroscopy, oral–pharyngeal transit, swallowing, deglutition

  5. The Consideration of Bolus Effects of Games Attached on Lesion area

    The aim of this study is to evaluate the effect of skin dose and PDD by using wounds protecting gauzes or Vaselinespread gauzes. And it was studied that the possibility to substitute custom bolus into gauzes. 4 MV photon (CL600C, varian, US), Polystyrene Phantom (30(W) X 30(L) X 30(H)) with Markus chamber(PTW, US) were used for dose measurement. This study was distinguished natural gauzes and spread over Vaseline gauzes. We gave variety to the gauze thickness at 5, 10 and 15 sheets respectively. For comparison between using bolus and not that, we had used 1.0 cm thickness bolus so that analyzed surface dose and PDD at the same conditions above mentioned. When maximum point was defined as reference point, surface dose was measured as 35% in open beam. When the gauzes were attached to surface as 5, 10 and 15 sheets, surface dose were increased as 69, 80 and 91% respectively according to thickness of gauzes. When spread over Vaseline gauzes were attached to surface as 5, 10 and 15 sheets, surface dose were increased respectively as 98, 100 and 98% according to thickness of gauzes. Also when 0.5 cm bolus and 5 sheets gauzes were composed, surface dose was measured as 98%. The gauzes that were attached to skin surface in radiation therapy had been scattering material and contributed increasing surface dose without variation of percentage depth dose. However, if we want to delivery much dose to skin surface then we have to apply many sheets of gauzes to skin surface. Although we get easy that result by bolus or spread over Vaseline gauzes, we have to revise percentage depth dose at calculation. Therefore, if we find pertinent conditions based on measured data that are considered skin dose and patient setup efficiency, to replace custom bolus with gauzes will be helpful to efficient treatment.

  6. Optimum bolus wizard settings in insulin pumps in children with Type 1 diabetes

    Andersen, A J B; Ostenfeld, A; Pipper, C B;

    2016-01-01

    AIM: To evaluate current insulin pump settings in an optimally regulated paediatric population using bolus wizard. METHODS: We used a retrospective study design to analyse data from 124 children on insulin pump therapy who had optimum HbA1c levels [... hypoglycaemic events. Bolus wizard settings were used to calculate the insulin to carbohydrate factors and insulin sensitivity factors. Multiple regression analysis was used to analyse the variables associated with the calculation factors. RESULTS: Insulin to carbohydrate factor varied from 276 in the youngest...

  7. Chase-and-run between adjacent cell populations promotes directional collective migration

    Theveneau, Eric; Steventon, Benjamin; Scarpa, Elena; Garcia, Simon; Trepat, Xavier; Streit, Andrea; Mayor, Roberto

    2016-01-01

    Collective cell migration in morphogenesis and cancer progression often involves the coordination of multiple cell types. How reciprocal interactions between adjacent cell populations lead to new emergent behaviours remains unknown. Here we studied the interaction between Neural Crest (NC) cells, a highly migratory cell population, and placodal cells, an epithelial tissue that contributes to sensory organs. We found that NC cells “chase” placodal cells by chemotaxis, while placodal cells “run” when contacted by NC. Chemotaxis to Sdf1 underlies the chase, while repulsion involving PCP and N-Cadherin signalling is responsible for the run. This “chase-and-run” requires the generation of asymmetric forces, which depend on local inhibition of focal adhesions. The cell interactions described here are essential for correct NC migration and for segregation of placodes in vivo and are likely to represent a general mechanism of coordinated migration. PMID:23770678

  8. Behavioral criteria of feedforward processing in rapid-chase theory: Some formal considerations

    Schmidt, Thomas

    2014-01-01

    The rapid-chase theory of response priming defines a set of behavioral criteria that indicate feedforward processing of visual stimulus features rather than recurrent processing. These feedforward criteria are strong predictions from a feedforward model that argues that sequentially presented prime and target stimuli lead to strictly sequential waves of visuomotor processing that can still be traced in continuous motor output, for instance, in pointing movements, muscle forces, or EEG readine...

  9. iChase: Supporting Exploration and Awareness of Editing Activities on Wikipedia

    Henry Riche, Nathalie; Lee, Bongshin; Chevalier, Fanny

    2010-01-01

    To increase its credibility and preserve the trust of its readers, Wikipedia needs to ensure a good quality of its articles. To that end, it is critical for Wikipedia administrators to be aware of contributors' editing activity to monitor vandalism, encourage reliable contributors to work on specific articles, or find mentors for new contributors. In this paper, we present iChase, a novel interactive visualization tool to provide administrators with better awareness of editing activities on W...

  10. Analysis and Throughput Optimization of Selective Chase Combining for OFDM Systems

    Shafique, Taniya; Zia, Muhammad; Han, Huy Dung

    2015-01-01

    In this paper, we present throughput analysis and optimization of bandwidth efficient selective retransmission method at modulation layer for conventional Chase Combining (CC) method under orthogonal frequency division multiplexing (OFDM) signaling. Most of the times, there are fewer errors in a failed packet and receiver can recover from errors receiving partial copy of original frame. The proposed selective retransmission method at modulation layer for OFDM modulation requests retransmissio...

  11. Unknown Safety and Efficacy of Smartphone Bolus Calculator Apps Puts Patients at Risk for Severe Adverse Outcomes.

    Hirsch, Irl B; Parkin, Christopher G

    2016-07-01

    Manual calculation of bolus insulin dosages can be challenging for individuals treated with multiple daily insulin injections (MDI) therapy. Automated bolus calculator capability has recently been made available via enhanced blood glucose meters and smartphone apps. Use of this technology has been shown to improve glycemic control and reduce glycemic variability without changing hypoglycemia; however, the clinical utility of app-based bolus calculators has not been demonstrated. Moreover, recent evidence challenges the safety and efficacy of these smartphone apps. Although the ability to automatically calculate bolus insulin dosages addresses a critical need of MDI-treated individuals, this technology raises concerns about efficacy of treatment and the protection of patient safety. This article discusses key issues and considerations associated with automated bolus calculator use. PMID:26798082

  12. The effect of food bolus location on jaw movement smoothness and masticatory efficiency

    W.N.B. Molenaar; P.J. Gezelle Meerburg; J. Luraschi; T. Whittle; M. Schimmel; F. Lobbezoo; C.C. Peck; G.M. Murray; I. Minami

    2012-01-01

    Masticatory efficiency in individuals with extensive tooth loss has been widely discussed. However, little is known about jaw movement smoothness during chewing and the effect of differences in food bolus location on movement smoothness and masticatory efficiency. The aim of this study was to determ

  13. Use of an automated bolus calculator in MDI-treated type 1 diabetes

    Schmidt, Signe; Meldgaard, Merete; Serifovski, Nermin;

    2012-01-01

    To investigate the effect of flexible intensive insulin therapy (FIIT) and an automated bolus calculator (ABC) in a Danish type 1 diabetes population treated with multiple daily injections. Furthermore, to test the feasibility of teaching FIIT in a 3-h structured course....

  14. Cardiorespiratory effects of intravenous bolus administration and infusion of ketamine-midazolam in dogs.

    Jacobson, J D; Hartsfield, S M

    1993-10-01

    Twelve healthy dogs were used to determine the cardiorespiratory effects of i.v. administered ketamine (10 mg/kg of body weight) and midazolam (0.5 mg/kg). Half the dogs received a ketamine-midazolam combination (K-M) as a bolus over 30 seconds and the other half received the K-M as an infusion over 15 minutes. Induction of anesthesia by use of K-M was good in all dogs. Ketamine-midazolam combination as a bolus or infusion induced minimal cardiorespiratory effects, except for significant (P dogs of the infusion group. Mild and transient respiratory depression was observed in dogs of both groups immediately after administration of K-M, but was greater in dogs of the bolus group than in dogs of the infusion group. Duration of action of K-M for chemical restraint was short. Salivation and defecation were observed in a few dogs. Extreme muscular tone developed in 1 dog after K-M bolus administration. PMID:8250397

  15. Tolerance to continuous intrathecal baclofen infusion can be reversed by pulsatile bolus infusion

    Heetla, H. W.; Staal, M. J.; van Laar, T.

    2010-01-01

    Study design: Pilot study. Objective: To study the effect of pulsatile bolus infusion of intrathecal baclofen (ITB) on daily ITB dose, in patients showing dose increases, probably due to tolerance. Setting: Department of neurology and neurosurgery, University Medical Center Groningen, the Netherland

  16. Improved evaluation of renal transplant perfusion by deconvolution of the artery bolus

    Full text: Perfusion indices can assist in renal transplant management. Chaiwatanarat et al. (J Nucl Med 1994; 35: 1792) deconvolved the artery bolus from the renal bolus to generate an index which discriminated between acute tubular necrosis (ATN) and acute rejection. We could not replicate this result, however, so we have investigated refinements to the method. Our criterion for success was separation between 13 ATN and 8 acute rejection patients, either on the basis of a single scan or when compared to a day 1 baseline scan. We acquired 40 one-second perfusion images and applied iliac artery, kidney and background ROls to generate background-corrected iliac artery and kidney curves. We applied the following methods of preprocessing the curves to optimize Fourier deconvolution: (1) the conventional method of appending a curve (cosine or exponential) to the end of the data at various points after the bolus peak; (2) a new approach of subtracting an estimate of the functional component from the renal curve before deconvolution. Neither method was successful with a single scan. When compared to a baseline scan, method 1 (as used in the above publication) still did not separate ATN and rejection, and varying the appended curves and their starting points did not help. When compared to a baseline scan, however, method 2 was successful providing the perfusion index was computed using the response function up to the end of the first pass of the artery bolus. The form of the function curve subtracted was found to be critical

  17. Lung Volume during Swallowing: Single Bolus Swallows in Healthy Young Adults

    Hegland, Karen M. Wheeler; Huber, Jessica E.; Pitts, Teresa; Sapienza, Christine M.

    2009-01-01

    Purpose: This study examined the relationship between swallowing and lung volume initiation in healthy adults during single swallows of boluses differing in volume and consistency. Differences in lung volume according to respiratory phase surrounding the swallow were also assessed. Method: Nine men and 11 women between the ages of 19 and 28 years…

  18. Pharmacokinetics of midazolam administered concurrently with ketamine after intravenous bolus or infusion in dogs.

    Brown, S A; Jacobson, J D; Hartsfield, S M

    1993-12-01

    Midazolam, a water-soluble benzodiazepine tranquilizer, has been considered by some veterinary anaesthesiologists to be suitable as a combination anaesthetic agent when administered concurrently with ketamine because of its water solubility and miscibility with ketamine. However, the pharmacokinetics of midazolam have not been extensively described in the dog. Twelve clinically healthy mixed breed dogs (22.2-33.4 kg) were divided into two groups at random and were administered ketamine (10 mg/kg) and midazolam (0.5 mg/kg) either as an intravenous bolus over 30 s (group 1) or as an i.v. infusion in 0.9% NaCl (2 ml/kg) over 15 min. Blood samples were obtained immediately before the drugs were injected and periodically for 6 h afterwards. Serum concentrations were determined using gas chromatography with electron-capture detection. Serum concentrations were best described using a two-compartment open model and indicated a t1/2-alpha of 1.8 min and t1/2-beta of 27.8 min after i.v. bolus, and t1/2-alpha of 1.35 min and t1/2-beta of 31.6 min after i.v. infusion. The calculated pharmacokinetic coefficient B was significantly smaller after i.v. infusion (429 +/- 244 ng/ml) than after i.v. bolus (888 +/- 130 ng/ml, P = 0.004). Furthermore, AUC was significantly smaller after i.v. infusion (29,800 +/- 6120 ng/h/ml) than after i.v. bolus (42,500 +/- 8460 ng/h/ml, P infusion (17.4 +/- 4.00 ml/min/kg than after i.v. bolus (12.1 +/- 2.24 ml/min/kg, P < 0.05). No other pharmacokinetic value was significantly affected by rate of intravenous administration. PMID:8126758

  19. Effects of a long-acting, trace mineral, reticulorumen bolus on range cow productivity and trace mineral profiles.

    Sprinkle, J E; Cuneo, S P; Frederick, H M; Enns, R M; Schafer, D W; Carstens, G E; Daugherty, S B; Noon, T H; Rickert, B M; Reggiardo, C

    2006-06-01

    The objectives were to determine if strategic supplementation of range cows with a long-acting (6 mo), trace mineral, reticulorumen bolus containing Cu, Se, and Co would: (1) increase cow BCS and BW, and calf birth, weaning, and postweaning weights, or weight per day of age (WDA); (2) increase liver concentrations of Cu or Zn in cows, or blood Se, Cu, or Zn concentrations in cows and calves; and (3) vary by cow breed for any of these response variables. There were 192 control and 144 bolused Composite cows (C; 25% Hereford, Angus, Gelbevieh, and Senepol or Barzona); 236 control and 158 bolused Hereford (H) cows; and 208 control and 149 bolused Brahman cross (B) cows used in a 3-yr experiment. Cows were weighed and scored for body condition in January, May, and September, and all bolused cows received boluses in January. Each year, from among the 3 breed groups a subset of 15 control and 15 bolused cows (n = 90) had samples obtained in January and May for liver Cu and Zn, blood Se, and serum Cu and Zn. As for cows, blood and serum from the calves of these cows were sampled each year in May and September for Cu, Se, and Zn. There was a significant breed x year x treatment interaction (P = 0.001) for cow weight loss from January to May. Calf WDA, weaning, and postweaning weights did not differ (P > 0.40) between bolused and control cows, but there was a significant (P = 0.022) breed x year x treatment interaction for birth weight. Liver Cu was deficient ( 0.50) in blood Se between treatment groups in January, but bolused cows had greater (P < 0.01) blood Se in May. Breed differences for blood Se concentrations existed for bolused cows, with B having greater (P < 0.05) blood Se than either C or H cows. Breed differences also existed for control cows, with H having less blood Se (P < 0.04) than B or C cows. Calves from bolused cows had greater blood Se than calves from control cows (P = 0.01). Supplementation via a long-acting trace mineral bolus was successful in

  20. EFFECT OF A BITTER BOLUS ON ORAL, PHARYNGEAL AND ESOPHAGEAL TRANSIT OF HEALTHY SUBJECTS

    Leda Maria Tavares ALVES

    2013-03-01

    Full Text Available Context During swallowing, boluses stimulate sensory receptors of the oral, pharyngeal, laryngeal, and esophageal regions. Sweet and tasteless foods are more acceptable for swallowing than bitter foods. A bitter bolus is unpleasant for most subjects. Our hypothesis was that the ingestion of a bitter bolus might alter the oral behavior, pharyngeal and esophageal transit when compared to a sweet bolus. Objective To evaluate whether the bitter taste of a liquid bolus causes alteration on oral, pharyngeal and/or esophageal transit in normal subjects in comparison with sweet bolus.' Method Scintigraphic evaluation of oral, pharyngeal and esophageal transit was performed in 43 asymptomatic subjects, 22 women and 21 men, ages 23-71 years, without problems with the ingestion of liquid and solid foods, and without digestive, cardiac or neurologic diseases. Each subject swallowed in random sequence and at room temperature 5 mL of a liquid bolus with bitter taste, prepared with 50 mL of water with 2 g of leaves of Peumus boldus, heated until boiling (boldus tea, and 5 mL of a liquid bolus with sweet taste, prepared with 50 mL of water with 3 g of sucrose, both labeled with 37 MBq of technetium phytate (Tc99m. Results There was no difference between the bitter bolus and the sweet bolus in mouth, pharynx and esophageal transit and clearance duration and in the amount of residues. Conclusion A bitter bolus, considered an unpleasant bolus, does not alter the duration of oral, pharyngeal and esophageal phases of swallowing, when compared with a sweet bolus, considered a pleasant bolus. Contexto Durante a deglutição o bolo estimula os receptores sensoriais da boca, faringe, laringe e esôfago. Os alimentos doces e sem gosto são mais aceitáveis para a deglutição do que os alimentos amargos, que tem gosto desagradável para a maioria dos indivíduos. A hipótese destes autores era que a ingestão de um bolo amargo pode alterar o trânsito oral

  1. Sci—Thur AM: YIS - 07: Design and production of 3D printed bolus for electron radiation therapy

    This is a proof-of-concept study demonstrating the capacity for modulated electron radiation therapy (MERT) using 3D printed bolus. Previous reports have involved bolus design using an electron pencil beam model and fabrication using a milling machine. In this study, an in-house algorithm is presented that optimizes the dose distribution with regard to dose coverage, conformity and homogeneity within planning target volume (PTV). The algorithm uses calculated result of a commercial electron Monte Carlo dose calculation as input. Distances along ray lines from distal side of 90% isodose to distal surface of PTV are used to estimate the bolus thickness. Inhomogeneities within the calculation volume are accounted for using coefficient of equivalent thickness method. Several regional modulation operators are applied to improve dose coverage and uniformity. The process is iterated (usually twice) until an acceptable MERT plan is realized, and the final bolus is printed using solid polylactic acid. The method is evaluated with regular geometric phantoms, anthropomorphic phantoms and a clinical rhabdomyosarcoma pediatric case. In all cases the dose conformity is improved compared to that with uniform bolus. The printed boluses conform well to the surface of complex anthropomorphic phantoms. For the rhabdomyosarcoma patient, the MERT plan yields a reduction of mean dose by 38.2% in left kidney relative to uniform bolus. MERT using 3D printed bolus appears to be a practical, low cost approach to generating optimized bolus for electron therapy. The method is effective in improving conformity of prescription isodose surface and in sparing immediately adjacent normal tissues

  2. Sci—Thur AM: YIS - 07: Design and production of 3D printed bolus for electron radiation therapy

    Su, Shiqin [Department of Physics and Atmospheric Science, Dalhousie University, Halifax, Nova Scotia (Canada); Moran, Kathryn [Queen Elizabeth II Health Sciences Centre, Nova Scotia Cancer Centre, Halifax, Nova Scotia (Canada); Robar, James L. [Department of Physics and Atmospheric Science, Dalhousie University, Halifax, Nova Scotia (Canada); Department of Radiation Oncology, Dalhousie University, Halifax, Nova Scotia (Canada)

    2014-08-15

    This is a proof-of-concept study demonstrating the capacity for modulated electron radiation therapy (MERT) using 3D printed bolus. Previous reports have involved bolus design using an electron pencil beam model and fabrication using a milling machine. In this study, an in-house algorithm is presented that optimizes the dose distribution with regard to dose coverage, conformity and homogeneity within planning target volume (PTV). The algorithm uses calculated result of a commercial electron Monte Carlo dose calculation as input. Distances along ray lines from distal side of 90% isodose to distal surface of PTV are used to estimate the bolus thickness. Inhomogeneities within the calculation volume are accounted for using coefficient of equivalent thickness method. Several regional modulation operators are applied to improve dose coverage and uniformity. The process is iterated (usually twice) until an acceptable MERT plan is realized, and the final bolus is printed using solid polylactic acid. The method is evaluated with regular geometric phantoms, anthropomorphic phantoms and a clinical rhabdomyosarcoma pediatric case. In all cases the dose conformity is improved compared to that with uniform bolus. The printed boluses conform well to the surface of complex anthropomorphic phantoms. For the rhabdomyosarcoma patient, the MERT plan yields a reduction of mean dose by 38.2% in left kidney relative to uniform bolus. MERT using 3D printed bolus appears to be a practical, low cost approach to generating optimized bolus for electron therapy. The method is effective in improving conformity of prescription isodose surface and in sparing immediately adjacent normal tissues.

  3. SU-C-213-05: Evaluation of a Composite Copper-Plastic Material for a 3D Printed Radiation Therapy Bolus

    Vitzthum, L; Ehler, E; Sterling, D; Reynolds, T; Higgins, P; Dusenbery, K [University of Minnesota, Minneapolis, MN (United States)

    2015-06-15

    Purpose: To evaluate a novel 3D printed bolus fabricated from a copper-plastic composite as a thin flexible, custom fitting device that can replicate doses achieved with conventional bolus techniques. Methods: Two models of bolus were created on a 3D printer using a composite copper-PLA/PHA. Firstly, boluses were constructed at thicknesses of 0.4, 0.6 and 0.8 mm. Relative dose measurements were performed under the bolus with an Attix Chamber as well as with radiochromic film. Results were compared to superficial Attix Chamber measurements in a water equivalent material to determine the dosimetric water equivalence of the copper-PLA/PHA plastic. Secondly, CT images of a RANDO phantom were used to create a custom fitting bolus across the anterolateral scalp. Surface dose with the bolus placed on the RANDO phantom was measured with radiochromic film at tangential angles with 6, 10, 10 flattening filter free (FFF) and 18 MV photon beams. Results: Mean surface doses for 6, 10, 10FFF and 18 MV were measured as a percent of Dmax for the flat bolus devices of each thickness. The 0.4 mm thickness bolus was determined to be near equivalent to 2.5 mm depth in water for all four energies. Surface doses ranged from 59–63% without bolus and 85–90% with the custom 0.4 mm copper-plastic bolus relative to the prescribed dose for an oblique tangential beam arrangement on the RANDO phantom. Conclusion: Sub-millimeter thickness, 3D printed composite copper-PLA/PHA bolus can provide a build-up effect equivalent to conventional bolus. At this thickness, the 3D printed bolus allows a level of flexure that may provide more patient comfort than current 3D printing materials used in bolus fabrication while still retaining the CT based custom patient shape. Funding provided by an intra-department grant of the University of Minnesota Department of Radiation Oncology.

  4. SU-C-213-05: Evaluation of a Composite Copper-Plastic Material for a 3D Printed Radiation Therapy Bolus

    Purpose: To evaluate a novel 3D printed bolus fabricated from a copper-plastic composite as a thin flexible, custom fitting device that can replicate doses achieved with conventional bolus techniques. Methods: Two models of bolus were created on a 3D printer using a composite copper-PLA/PHA. Firstly, boluses were constructed at thicknesses of 0.4, 0.6 and 0.8 mm. Relative dose measurements were performed under the bolus with an Attix Chamber as well as with radiochromic film. Results were compared to superficial Attix Chamber measurements in a water equivalent material to determine the dosimetric water equivalence of the copper-PLA/PHA plastic. Secondly, CT images of a RANDO phantom were used to create a custom fitting bolus across the anterolateral scalp. Surface dose with the bolus placed on the RANDO phantom was measured with radiochromic film at tangential angles with 6, 10, 10 flattening filter free (FFF) and 18 MV photon beams. Results: Mean surface doses for 6, 10, 10FFF and 18 MV were measured as a percent of Dmax for the flat bolus devices of each thickness. The 0.4 mm thickness bolus was determined to be near equivalent to 2.5 mm depth in water for all four energies. Surface doses ranged from 59–63% without bolus and 85–90% with the custom 0.4 mm copper-plastic bolus relative to the prescribed dose for an oblique tangential beam arrangement on the RANDO phantom. Conclusion: Sub-millimeter thickness, 3D printed composite copper-PLA/PHA bolus can provide a build-up effect equivalent to conventional bolus. At this thickness, the 3D printed bolus allows a level of flexure that may provide more patient comfort than current 3D printing materials used in bolus fabrication while still retaining the CT based custom patient shape. Funding provided by an intra-department grant of the University of Minnesota Department of Radiation Oncology

  5. OPTIMAL REGIMENS OF THE BASAL-BOLUS INSULIN THERAPY IN ADOLESCENTS WITH TYPE 1 DIABETES MELLITUS

    G. A. Galkina

    2015-01-01

    Full Text Available This study was aimed to determine peculiarities in regimens of the pump insulin therapy and to reveal the optimal basal-to-bolus insulin ratio that are necessary for achieving optimal glycemic control in adoles-cents with type 1 diabetes mellitus (T1DM.  82 adolescents at the age of 14–18 with T1DM, using continuous subcutaneous insulin infusion (CSII from 5 months to 7.5 years were monitored with continuous glucose monitoring (CGM system «Guar-dian Real Time» or CGM system, built in MiniMed Paradigm Revel System 722 (Medtronic Minimed, USA. Assessing the quality of glycaemic control was based on the level of glycated haemoglobin (HbA1c. The results of CGM were reviewed and average for 3 days performances: total daily dose of insulin, dose of basal and bolus insulin, basal-to-bolus insulin ratio, carbohydrate content of the meal, expressed in BE, carbohydrate ratio, insulin sensitivity factor were determined. The patients were subdivided into 2 groups: group 1 – adolescents with the optimal/suboptimal glycemic control (n = 55, 2 – adolescents with long-standing poorly controlled T1DM (n = 27. Average total daily dose of basal insulin (U in a day, U per kg in a day in adolescents group 1 was significantly higher, com-pared with patients in group 2 (р = 0.043; р = 0.038 respectively. Patients in group 2 received more car-bohydrates with a meal intake and had higher doses of average total daily bolus insulin. The average ba-sal-to-bolus ratio from group 1 patients was 51/49%, compared with group 2 patients – 45/55% (р = 0.026.  An important condition for achieving optimal glycemic control is a high level of compliance and skills of adolescents. Optimal well-balanced basal-to-bolus insulin ratio in adolescents with T1DM on CSII, which can provide improvements in blood glucose management and reducing the risk of complications of the disease, is 51/49%. 

  6. Comparison of Three Different Helmet Bolus Device for Total Scalp Irradiation

    This study evaluated the usefulness of Helmet bolus device using Bolx-II, paraffin wax, solid thermoplastic material in total scalp irradiation. Using Rando phantom, we applied Bolx-II (Action Products, USA), paraffin wax (Densply, USA), solid thermoplastic material (Med-Tec, USA) on the whole scalp to make helmet bolus device. Computed tomography (GE, Ultra Light Speed16) images were acquired at 5 mm thickness. Then, we set up the optimum treatment plan and analyzed the variation in density of each bolus (Philips, Pinnacle). To evaluate the dose distribution, Dose-homogeneity index (DHI, D90/D10) and Conformity index (CI, V95/TV) of Clinical Target Volume (CTV) using Dose-Volume Histogram (DVH) and V20,V30 of normal brain tissues. we assessed the efficiency of production process by measuring total time taken to produce. Thermoluminescent dosimeters (TLD) were used to verify the accuracy. Density variation value of Bolx-II, paraffin wax, solid thermoplastic material turned out to be 0.952±0.13 g/cm3, 0.842±0.17 g/cm3, 0.908±0.24 g/cm3, respectively. The DHI and CI of each helmet bolus device which used Bolx-II, paraffin wax, solid thermoplastic material were 0.89, 0.85, 0.77 and 0.86, 0.78, 0.74, respectively. The result of Bolx-II was the best. V20 and V30 of brain tissues were 11.50%, 10.80%, 10.07% and 7.62%, 7.40%, 7.31%, respectively. It took 30, 120, 90 minutes to produce. The measured TLD results were within ±7% of the planned values. The application of helmet bolus which used Bolx-II during total scalp irradiation not only improves homogeneity and conformity of Clinical Target Volume but also takes short time and the production method is simple. Thus, the helmet bolus which used Bolx-II is considered to be useful for the clinical trials.

  7. Chasing behaviour and optomotor following in free-flying male blowflies: flight performance and interactions of the underlying control systems

    Christine Trischler

    2010-05-01

    Full Text Available The chasing behaviour of male blowflies after small targets belongs to the most rapid and virtuosic visually guided behaviours found in nature. Since in a structured environment any turn towards a target inevitably leads to a displacement of the entire retinal image in the opposite direction, it might evoke optomotor following responses counteracting the turn. To analyse potential interactions between the control systems underlying chasing behaviour and optomotor following, respectively, we performed behavioural experiments on male blowflies and examined the characteristics of the two flight control systems in isolation and in combination. Three findings are particularly striking. (i The characteristic saccadic flight and gaze style – a distinctive feature of blowfly cruising flights – is largely abandoned when the entire visual surroundings move around the fly; in this case flies tend to follow the moving pattern in a relatively continuous and smooth way. (ii When male flies engage in following a small target, they also employ a smooth pursuit strategy. (iii Although blowflies are reluctant to fly at high background velocities, the performance and dynamical characteristics of the chasing system are not much affected when the background moves in either the same or in the opposite direction as the target. Hence, the optomotor following response is largely suppressed by the chasing system and does not much impair chasing performance.

  8. Should colloid boluses be prioritized over crystalloid boluses for the management of dengue shock syndrome in the presence of ascites and pleural effusions?

    Weerasinghe Mindu

    2011-02-01

    Full Text Available Abstract Background Although the WHO guideline for the management of dengue fever considers the presence of ascites or pleural effusions in the diagnosis of DSS, it does not emphasize the importance of their presence when selecting fluids for resuscitation. Case presentation We highlight three patients with DSS who received boluses of crystalloids on priority basis as recommended by WHO guidelines during resuscitation. All three patients had varying degrees of third space fluid loss (ascites and pleural effusions at the time of development of DSS. Ascites and pleural effusions were detected in all 3 patients at the time of shock irrespective of whether iv fluids were given or not. All three patients had documented liver involvement at the time of shock evidenced by elevation of AST (4800 iu/L, 5000 iu/L and 1960 iu/L. One patient who had profound shock died 6 hours after admission with evidence of acute pulmonary oedema in the convalescence phase. All of them needed CPAP ventilator support and potent diuretics. Conclusions We therefore feel that resuscitation of patients with DSS who already have third space fluid accumulation with crystalloid boluses on priority basis may contribute to recovery phase pulmonary oedema.

  9. F-18 chase craft with NASA test pilots Schneider and Fulton

    1992-01-01

    Ed Schneider, (left), is the project pilot for the F-18 High Angle of Attack program at NASA's Dryden Flight Research Center, Edwards, California. He has been a NASA research pilot at Dryden since 1983. In addition to his assignment with the F-18 High Angle of Attack program, Schneider is a project pilot for the F-15B aeronautical research aircraft, the NASA NB-52B launch aircraft, and the SR-71 'Blackbird' aircraft. He is a Fellow and was the 1994 President of the Society of Experimental Test Pilots. In 1996 he was awarded the NASA Exceptional Service Medal. Schneider is seen here with Fitzhugh L. Fulton Jr., (right), who was a civilian research pilot at Dryden. from August 1, 1966, until July 3, 1986, following 23 years of service as a pilot in the U.S. Air Force. Fulton was the project pilot on all early tests of the 747 Shuttle Carrier Aircraft (SCA) used to air launch the Space Shuttle prototype Enterprise in the Approach and Landing Tests (ALT) at Dryden in l977. For his work in the ALT program, Fulton received NASA's Exceptional Service Medal. He also received the Exceptional Service Medal again in 1983 for flying the 747 SCA during the European tour of the Space Shuttle Enterprise. During his career at Dryden, Fulton was project pilot on NASA's NB-52B launch aircraft used to air launch a variety of piloted and unpiloted research aircraft, including the X-15s and lifting bodies. He flew the XB-70 prototype supersonic bomber on both NASA-USAF tests and NASA research flights during the late 1960s, attaining speeds exceeding Mach 3. He was also a project pilot on the YF-12A and YF-12C research program from April 14, 1969, until September 25, 1978. The F/A-18 Hornet seen behind them is used primarily as a safety chase and support aircraft at NASA's Dryden Flight Research Center, Edwards, Calif. As support aircraft, the F-18's are used for safety chase, pilot proficiency and aerial photography. As a safety chase aircraft, F-18's, flown by research pilots

  10. War and the Media in Border Minstrelsy: The Ballad of Chevy Chase (book chapter)

    Perry, Ruth

    2010-01-01

    The ballad of Chevy Chase is a very old ballad, probably dating back to the fifteenth century and referring to events that transpired in the middle of that century or even back to the fourteenth century. Appreciated by writers and singers from feudal times to the age of Enlightenment, this ballad also crossed the line from oral culture to manuscript and printed text and back again—moving back and forth between broadside and song, sometimes part of a living tradition and sometimes an antiquari...

  11. Development and Dosimetric Characterization of a Tissue Substitute (Bolus) For Use in Linear Accelerator Electron Radiotherapy

    We propose the design of a new custom made material, to be used as a tissue substitute in external beam electron radiotherapy, based on cotton fabric and beeswax. Due to its inexpensive, easy preparation, constant thickness, flexibility, uniform density and physical properties similar to those of soft tissue, this bolus will insure personalized optimal dose build up and dose distribution in irregular treatment regions. Materials and Methods: We used commercial Campeche beeswax and 100% cotton fabric to prepare the bolus. Beeswax's physical characteristics were determined by thermal and density analysis. Its chemical properties are to be determined by electronic microscopy. We performed quality control tests and calibration of the Varian 2100C linear accelerator. The tissue equivalence of the material is established for a range of electron energies (6, 9, 12, 16, 20 MeV) using a water equivalent solid phantom (PTW; Freiburg, Germany) and a plane parallel ionization chamber (PTW) associated to a PTW electrometer. Results: Beeswax's absolute density was found to be 0.9181g/ml at 21 deg. C, with a melting point of 45 deg. C. For the bolus elaboration, the cotton fabric was soaked in liquid beeswax and thin sheets of approximately 1 mm were obtained. These presented high flexibility, physical stability (color, texture, thickness) and homogeneity. Determination of this dosimetric characteristics and equivalent thickness are still in process. Discussion and conclusions: Our preliminary results suggest that the tissue substitute is easily made, inexpensive to produce, molds well to the treatment area and its positioning is easy and reproducible over the course of the treatment. So we consider that it's a good alternative to the commercial bolus

  12. Comparison of continuous epidural infusion and programmed intermittent epidural bolus in labor analgesia

    Lin Y; Li Q; Yang R; Liu J

    2016-01-01

    Yunan Lin, Qiang Li, Jinlu Liu, Ruimin Yang, Jingchen Liu Department of Anesthesiology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, People’s Republic of China Background: This study aims to investigate differences between continuous epidural infusion (CEI) and programmed intermittent epidural bolus (IEB) analgesia for the Chinese parturients undergoing spontaneous delivery and to approach their safety to parturients and neonates.Methods: Two hundred ...

  13. Surfactant bolus instillation: effects of different doses on blood pressure and cerebral blood flow velocities

    Rey, M.; Segerer, Hugo; Kiessling, C.; Obladen, Michael

    1994-01-01

    Fifteen preterm infants suffering from respiratory distress syndrome were randomly allocated to receive either high-dose (200 mg/kg) or low-dose (100 mg/kg) surfactant treatment. Retreatments were done with the low dose. Blood pressure, blood gases and cerebral blood flow velocities were determined before and after 24 bolus instillations. With the high dose mean blood pressure and mean cerebral blood flow velocity dropped significantly. With the low dose only mean cerebral blood flow velocity...

  14. Dopamine D(2) receptor quantification in extrastriatal brain regions using [(123)I]epidepride with bolus/infusion

    Pinborg, L H; Videbaek, C; Knudsen, G M;

    2000-01-01

    The iodinated benzamide epidepride, which shows a picomolar affinity binding to dopamine D(2) receptors, has been designed for in vivo studies using SPECT. The aim of the present study was to apply a steady-state condition by the bolus/infusion approach with [(123)I]epidepride for the...... bolus/infusion (B/I) experiment was applied. It was predicted that a B/I protocol with infusion of one-third of the initial bolus per hour would be appropriate. Steady-state conditions were attained in extrastriatal regions within 3-4 h but the infusion continued up to 7 h in order to minimize the...... has a unique signal-to-noise ratio compared to [(123)I]IBZM but present difficulties for steady-state measurements of striatal regions. The bolus/infusion approach is particularly feasible for quantification of the binding potential in extrastriatal regions....

  15. Electrical characterization of bolus material as phantom for use in electrical impedance and computed tomography fusion imaging

    Parvind Kaur Grewal

    2014-04-01

    Full Text Available Phantoms are widely used in medical imaging to predict image quality prior to clinical imaging. This paper discusses the possible use of bolus material, as a conductivity phantom, for validation and interpretation of electrical impedance tomography (EIT images. Bolus is commonly used in radiation therapy to mimic tissue. When irradiated, it has radiological characteristics similar to tissue. With increased research interest in CT/EIT fusion imaging there is a need to find a material which has both the absorption coefficient and electrical conductivity similar to biological tissues. In the present study the electrical properties, specifically resistivity, of various commercially available bolus materials were characterized by comparing their frequency response with that of in-vivo connective adipose tissue. It was determined that the resistivity of Gelatin Bolus is similar to in-vivo tissue in the frequency range 10 kHz to 1MHz and therefore has potential to be used in EIT/CT fusion imaging studies.

  16. Accuracy of pencil-beam redefinition algorithm dose calculations in patient-like cylindrical phantoms for bolus electron conformal therapy

    Purpose: The purpose of this study was to document the improved accuracy of the pencil beam redefinition algorithm (PBRA) compared to the pencil beam algorithm (PBA) for bolus electron conformal therapy using cylindrical patient phantoms based on patient computed tomography (CT) scans of retromolar trigone and nose cancer.Methods: PBRA and PBA electron dose calculations were compared with measured dose in retromolar trigone and nose phantoms both with and without bolus. For the bolus treatment plans, a radiation oncologist outlined a planning target volume (PTV) on the central axis slice of the CT scan for each phantom. A bolus was designed using the planning.decimal® (p.d) software (.decimal, Inc., Sanford, FL) to conform the 90% dose line to the distal surface of the PTV. Dose measurements were taken with thermoluminescent dosimeters placed into predrilled holes. The Pinnacle3 (Philips Healthcare, Andover, MD) treatment planning system was used to calculate PBA dose distributions. The PBRA dose distributions were calculated with an in-house C++ program. In order to accurately account for the phantom materials a table correlating CT number to relative electron stopping and scattering powers was compiled and used for both PBA and PBRA dose calculations. Accuracy was determined by comparing differences in measured and calculated dose, as well as distance to agreement for each measurement point.Results: The measured doses had an average precision of 0.9%. For the retromolar trigone phantom, the PBRA dose calculations had an average ±1σ dose difference (calculated − measured) of −0.65%± 1.62% without the bolus and −0.20%± 1.54% with the bolus. The PBA dose calculation had an average dose difference of 0.19%± 3.27% without the bolus and −0.05%± 3.14% with the bolus. For the nose phantom, the PBRA dose calculations had an average dose difference of 0.50%± 3.06% without bolus and −0.18%± 1.22% with the bolus. The PBA dose calculations had an average

  17. Development of a universal dual-bolus injection scheme for the quantitative assessment of myocardial perfusion cardiovascular magnetic resonance

    Alfakih Khaled

    2011-05-01

    Full Text Available Abstract Background The dual-bolus protocol enables accurate quantification of myocardial blood flow (MBF by first-pass perfusion cardiovascular magnetic resonance (CMR. However, despite the advantages and increasing demand for the dual-bolus method for accurate quantification of MBF, thus far, it has not been widely used in the field of quantitative perfusion CMR. The main reasons for this are that the setup for the dual-bolus method is complex and requires a state-of-the-art injector and there is also a lack of post processing software. As a solution to one of these problems, we have devised a universal dual-bolus injection scheme for use in a clinical setting. The purpose of this study is to show the setup and feasibility of the universal dual-bolus injection scheme. Methods The universal dual-bolus injection scheme was tested using multiple combinations of different contrast agents, contrast agent dose, power injectors, perfusion sequences, and CMR scanners. This included 3 different contrast agents (Gd-DO3A-butrol, Gd-DTPA and Gd-DOTA, 4 different doses (0.025 mmol/kg, 0.05 mmol/kg, 0.075 mmol/kg and 0.1 mmol/kg, 2 different types of injectors (with and without "pause" function, 5 different sequences (turbo field echo (TFE, balanced TFE, k-space and time (k-t accelerated TFE, k-t accelerated balanced TFE, turbo fast low-angle shot and 3 different CMR scanners from 2 different manufacturers. The relation between the time width of dilute contrast agent bolus curve and cardiac output was obtained to determine the optimal predefined pause duration between dilute and neat contrast agent injection. Results 161 dual-bolus perfusion scans were performed. Three non-injector-related technical errors were observed (1.9%. No injector-related errors were observed. The dual-bolus scheme worked well in all the combinations of parameters if the optimal predefined pause was used. Linear regression analysis showed that the optimal duration for the predefined

  18. Electrical characterization of bolus material as phantom for use in electrical impedance and computed tomography fusion imaging

    Parvind Kaur Grewal; Majid Shokoufi; Jeff Liu; Krishnan Kalpagam; Kirpal Singh Kohli

    2014-01-01

    Phantoms are widely used in medical imaging to predict image quality prior to clinical imaging. This paper discusses the possible use of bolus material, as a conductivity phantom, for validation and interpretation of electrical impedance tomography (EIT) images. Bolus is commonly used in radiation therapy to mimic tissue. When irradiated, it has radiological characteristics similar to tissue. With increased research interest in CT/EIT fusion imaging there is a need to find a material which h...

  19. Dynamic properties of chasers in a moving queue based on a delayed chasing model

    Ning, Guo; Jian-Xun, Ding; Xiang, Ling; Qin, Shi; Reinhart, Kühne

    2016-05-01

    A delayed chasing model is proposed to simulate the chase behavior in the queue, where each member regards the closest one ahead as the target, and the leader is attracted to a target point with slight fluctuation. When the initial distances between neighbors possess an identical low value, the fluctuating target of the leader can cause an amplified disturbance in the queue. After a long period of time, the queue recovers the stable state from the disturbance, forming a straight-line-like pattern again, but distances between neighbors grow. Whether the queue can keep stable or not depends on initial distance, desired velocity, and relaxation time. Furthermore, we carry out convergence analysis to explain the divergence transformation behavior and confirm the convergence conditions, which is in approximate agreement with simulations. Project supported by the National Natural Science Foundation of China (Grant Nos. 71071044, 71001001, 71201041, and 11247291), the Doctoral Program of the Ministry of Education of China (Grant Nos. 20110111120023 and 20120111120022), the Postdoctoral Fund Project of China (Grant No. 2013M530295), the National Basic Research Program of China (Grant No. 2012CB725404), and 1000 Plan for Foreign Talent, China (Grant No. WQ20123400070).

  20. "Chasing Spots"

    Höltgen, Stefan

    2010-01-01

    Das Berliner Computerspiele-Museum stellt zusammen mit einem Special Guest pünktlich zur Games Convention 2009 eine "History of Videogames"-Timeline vor. Die Geschichte der Videospiele ist am Maßstab der Mediengeschichte gemessen noch recht jung. Als Kapitel des Computerzeitalters ist sie jedoch längst Gegenstand archäologischen Interesses. Das Berliner Computerspiele-Museum hat jetzt eine interaktive "History of Videogames" auf seinen Webseiten veröffentlicht, die nach und nach die wesentlic...

  1. Chasing Patents

    Menezes, Flavio Marques; Pitchford, Rohan

    2002-01-01

    We examine the problem faced by a company that wishes to purchase patents in the hands of two di¤erent patent owners. Complementarity of these patents in the production process of the company is a prime e¢ciency reason for them being owned (or licenced) by the company. We show that this very same complementarity can lead to patent owners behaving strategically in bargaining, and delaying their sale to the company. When the company is highly leveraged, such ine¢cient delay is limited. Comparat...

  2. Chasing volatility

    Caporin, Massimiliano; Rossi, Eduardo; Santucci de Magistris, Paolo

    The realized volatility of financial returns is characterized by persistence and occurrence of unpreditable large increments. To capture those features, we introduce the Multiplicative Error Model with jumps (MEM-J). When a jump component is included in the multiplicative specification, the...... estimate alternative specifications of the model using a set of daily bipower measures for 7 stock indexes and 16 individual NYSE stocks. The estimates of the jump component confirm that the probability of jumps dramatically increases during the financial crisis. Compared to other realized volatility...... models, the introduction of the jump component provides a sensible improvement in the fit, as well as for in-sample and out-of-sample volatility tail forecasts....

  3. Esophageal contractions, bolus transit and perception of transit after swallows of liquid and solid boluses in normal subjects Contrações esofágicas, trânsito do bolo e percepção do trânsito após deglutições de bolos líquido e sólido em voluntários normais

    Juciléia Dalmazo

    2012-12-01

    Full Text Available CONTEXT: Esophageal dysphagia is the sensation that the ingested material has a slow transit or blockage in its normal passage to the stomach. It is not always associated with motility or transit alterations. OBJECTIVES: To evaluate in normal volunteers the possibility of perception of bolus transit through the esophagus after swallows of liquid and solid boluses, the differences in esophageal contraction and transit with these boluses, and the association of transit perception with alteration of esophageal contraction and/or transit. METHODS: The investigation included 11 asymptomatic volunteers, 4 men and 7 women aged 19-58 years. The subjects were evaluated in the sitting position. They performed swallows of the same volume of liquid (isotonic drink and solid (macaroni boluses in a random order and in duplicate. After each swallow they were asked about the sensation of bolus passage through the esophagus. Contractions and transit were evaluated simultaneously by solid state manometry and impedance. RESULTS: Perception of bolus transit occurred only with the solid bolus. The amplitude and area under the curve of contractions were higher with swallows of the solid bolus than with swallows of the liquid bolus. The difference was more evident in swallows with no perception of transit (n = 12 than in swallows with perception (n = 10. The total bolus transit time was longer for the solid bolus than for the liquid bolus only with swallows followed by no perception of transit. CONCLUSION: The results suggest that the perception of esophageal transit may be the consequence of inadequate adaptation of esophageal transit and contraction to the characteristics of the swallowed bolus.CONTEXTO: Disfagia esofágica é a sensação de que o alimento ingerido tem trânsito lento ou é bloqueado em sua passagem para o estômago. Nem sempre o sintoma é associado com alterações em trânsito ou motilidade. OBJETIVOS: Avaliar, em voluntários normais, a

  4. A pulse-chase strategy for EdU labelling assay is able to rapidly quantify cell division orientation.

    Yin, Xiaofeng; Tsukaya, Hirokazu

    2016-09-01

    Measurement of the direction of cell division is an important, yet difficult, task to analyse how a plant organ acquires its final shape from an initially small group of cells. We introduce a method that rapidly and easily quantifies cell division direction and is applicable to all plant species. A pulse-chase strategy for 5-ethynyl-2'-deoxyuridine (EdU) labelling assay was established and was shown to be successful for leaves of Arabidopsis thaliana (Arabidopsis) and Juncus prismatocarpus. By optimization of the pulse and chase periods, most of the signals obtained were sets of daughter nuclei. For Arabidopsis, the optimal time was a 45-min pulse and a 7-h chase. For J. prismatocarpus, the optimal time was a 2-h pulse and a 13.5-h chase. The positions of the daughter nuclei were used to quantify cell division direction in the Arabidopsis leaf primordia. Overall, cell division along the proximal-distal axis was more frequent than along the medial-lateral axis. In petiole, major vein, minor vein and margin areas, the major cell division direction seemed to be coincident with the direction of auxin flow. The advantages of our method over the few methods used previously are discussed. We anticipate that it will provide opportunities to study plant development in the near future. PMID:27121010

  5. Biosynthesis of intestinal microvillar proteins. Pulse-chase labelling studies on maltase-glucoamylase, aminopeptidase A and dipeptidyl peptidase IV

    Danielsen, E M; Sjöström, H; Norén, Ove

    1983-01-01

    The biogenesis of three intestinal microvillar enzymes, maltase-glucoamylase (EC 3.2.1.20), aminopeptidase A (aspartate aminopeptidase, EC 3.4.11.7) and dipeptidyl peptidase IV (EC 3.4.14.5), was studied by pulse-chase labelling of pig small-intestinal explants kept in organ culture. The earliest...

  6. Biosynthesis of intestinal microvillar proteins. Pulse-chase labelling studies on aminopeptidase N and sucrase-isomaltase

    Danielsen, Erik Michael

    1982-01-01

    The biogenesis of two microvillar enzymes, aminopeptidase N (EC 3.4.11.2) and sucrase (EC 3.2.1.48)-isomaltase (EC 3.2.1.10), was studied by pulse-chase labelling of pig small-intestinal explants kept in organ culture. Both enzymes became inserted into the membrane during or immediately after...

  7. Self-Service Computerized Bibliographic Retrieval: A Comparison of Colleague and PaperChase, Programs That Search the MEDLINE Database

    Porter, Douglas; Wigton, Robert S.; Reidelbach, Marie A.; Bleich, Howard L.; Slack, Warner V.

    1988-01-01

    Colleague and PaperChase are the two most widely used computer systems designed for clinicians and scientists who wish to search the National Library of Medicine's MEDLINE data base of biomedical references. The present study compares the performance of these two systems.

  8. Understanding Within-Session Loss-Chasing: An Experimental Investigation of the Impact of Stake Size on Cognitive Control.

    Parke, Adrian; Harris, Andrew; Parke, Jonathan; Goddard, Paul

    2016-06-01

    Loss-chasing is a central feature of problematic gambling, yet it remains a poorly conceived and understood concept. Loss-chasing is believed to stem from an erosion of cognitive control when gambling. The opportunity to gamble at significantly disparate stake sizes on a gambling activity is considered to be a risk factor for loss-chasing. This study investigated the impact of gambling at disparate stake sizes on executive processes integral to maintaining cognitive control when gambling, namely response inhibition and reflection impulsivity. Frequent adult non-problem gamblers (n = 32) participated in a repeated measures experiment; and gambled at three disparate stake sizes (£20, £2 and no stake per bet) on a simulated gambling task. Participants' response inhibition performance and reflection impulsivity levels after gambling at various stake sizes were compared via a go/no-go task and information sampling task, respectively. Quality of decision-making i.e. the evaluation of available information to make probability judgements was impaired after gambling at higher stakes in comparison to lower stakes, indicating an increase in reflection impulsivity. No effect on response inhibition was observed. Although exploratory, this suggests that the opportunity for participants to substantially increase stake size on a gambling activity may be a risk factor for impaired cognitive performance when gambling, and perhaps create vulnerability for within-session loss-chasing in some players. PMID:26323795

  9. Biosynthesis of the D2 cell adhesion molecule: pulse-chase studies in cultured fetal rat neuronal cells

    Lyles, J M; Norrild, B; Bock, E

    1984-01-01

    chase times the Mr of both molecules increased to 187,000-201,000 (A) and 137,000-158,000 (B). These were similar to the sizes of D2-CAM labeled with [14C]glucosamine, [3H]fucose and [14C]mannosamine, indicating that the higher Mr species are glycoproteins. In the presence of tunicamycin, which...

  10. Tissue distribution of 3H-nicotine in rats after bolus or constant injection

    Two groups of rats, (N = 7), were fasted for 24 hrs prior to the study. On the day of the experiment, the animals were anesthetized and infused with either 5 ml nicotine solution (200 μg/L) in saline containing 5 μc 3H-nicotine, (sp. activity 50-80 mCi/mol) for 90 minutes or injected as a bolus with 0.5 ml of the same nicotine (200 μg/L) solution. The animals were sacrificed 60 minutes after the injection or after the infusion was stopped. Blood and tissue samples were counted by liquid scintillation counting. Percent distribution of 3H-nicotine per gm of tissue was calculated from the total radioactivity recovered in individual tissues over the total activity injected into the rat and the values were compared using student's t test. Results: Distribution of 3H-nicotine was found highest in kidney (45-49%) among all tissues examined and was not different between routes of administration. Significantly higher retention of 3H-nicotine was found with continuous infusion in esophagus, fundus, antrum, spleen, cecum, pancreas, testes, heart and muscle when 3H-nicotine retentions were compared with bolus injection. In contrast, the distribution of 3H-nicotine in adrenal gland, was significantly lower in continuous infusion group. Distribution in blood was 6 fold higher in continuous infusion (7.26%) compared to bolus (1.11%) injection. The distribution 3H-nicotine in other tissues were not different by either routes of injection

  11. Prevalence of eosinophilic oesophagitis in adults presenting with oesophageal food bolus obstruction

    Neel; Heerasing; Shok; Yin; Lee; Sina; Alexander; Damian; Dowling

    2015-01-01

    AIM: To look at the relationship between eosinophilic oesophagitis(EO) and food bolus impaction in adults. METHODS: We retrospectively analysed medical records of 100 consecutive patients who presented to our hospital with oesophageal food bolus obstruction(FBO) between 2012 and 2014. In this cohort, 96 were adults(64% male), and 4 paediatric patients were excluded from the analysis as our centre did not have paediatric gastroenterologists. Eighty-five adult patients underwent emergency gastroscopy. The food bolus was either advanced into the stomach using the push technique or retrieved using a standard retrieval net. Biopsies were obtained in 51 patients from the proximal and distal parts of the oesophagus at initial gastroscopy. All biopsy specimens were assessed and reviewed by dedicated gastrointestinal pathologists at the Department of Pathology, University Hospital Geelong. The diagnosis of EO was defined and established by the presence of the following histological features:(1) peak eosinophil counts > 20/hpf;(2) eosinophil microabscess;(3) superficial layering of eosinophils;(4) extracellular eosinophil granules;(5) basal cell hyperplasia;(6) dilated intercellular spaces; and(7) subepithelial or lamina propria fibrosis. The histology results of the biopsy specimens were accessed from the pathology database of the hospital and recorded for analysis. RESULTS: Our cohort had a median age of 60. Seventeen/51(33%) patients had evidence of EO on biopsy findings. The majority of patients with EO were male(71%). Classical endoscopic features of oesophageal rings, furrows or white plaques and exudates werefound in 59% of patients with EO. Previous episodes of FBO were present in 12/17 patients and 41% had a history of eczema, hay fever or asthma. Reflux oesophagitis and benign strictures were found in 20/34 patients who did not have biopsies. CONCLUSION: EO is present in approximately one third of patients who are admitted with FBO. Biopsies should be performed

  12. A comparison of bolus injection of landiolol versus oral administration of propranolol before cardiac computed tomography

    Nakamura, Yoshitaka; Yamaji, Kyohei; Saho, Tatsunori; Matsuzaki, Zyousin; Yuda, Itsuo; Soga, Yoshimitsu; Shirai, Shinichi; Ando, Kenji; Nobuyoshi, Masakiyo

    2014-01-01

    Heart rate (HR) reduction is essential to achieve good image quality for cardiac computed tomography (CCT). We evaluated the efficacy of a bolus injection of landiolol, an ultra-short acting β-blocker, without the administration of oral β-blocker to reduce HR prior to CCT. We enrolled 678 consecutive patients who underwent CCT from December 2011 to March 2012 and divided them into three groups, which were a propranolol group (n = 277), a low-dose landiolol group (n = 188), and a high-dose lan...

  13. OPTIMAL REGIMENS OF THE BASAL-BOLUS INSULIN THERAPY IN ADOLESCENTS WITH TYPE 1 DIABETES MELLITUS

    G A Galkina; A. A. Voropay; M. A. Levkovich; S. V. Vorobiov; M V Komkova; N. V. Morozova

    2015-01-01

    This study was aimed to determine peculiarities in regimens of the pump insulin therapy and to reveal the optimal basal-to-bolus insulin ratio that are necessary for achieving optimal glycemic control in adoles-cents with type 1 diabetes mellitus (T1DM).  82 adolescents at the age of 14–18 with T1DM, using continuous subcutaneous insulin infusion (CSII) from 5 months to 7.5 years were monitored with continuous glucose monitoring (CGM) system «Guar-dian Real Time» or CGM system, built in MiniM...

  14. The benefit of individualized custom bolus in the postmastectomy radiation therapy: numerical analysis with 3-D treatment planning

    Cho, Jae Ho; Cho, Kwang Hwan; Keum, Ki Chang; Han, Yong Yih; Kim, Yong Bae; Chu, Sung Sil; Suh, Chang Ok [College of Medicine, Yonsei Univ., Seoul (Korea, Republic of)

    2003-03-01

    To reduce the irradiation dose to the lungs and heart in the case of chest wall irradiation using an oppositional electron beam, we used an individualized custom bolus, which was precisely designed to compensate for the differences in chest wall thickness. The benefits were evaluated by comparing the normal tissue complication probabilities (NTCPs) and dose statistics both with and without boluses Boluses were made, and their effects evaluated in ten patients treated using the reverse hockey-stick technique. The electron beam energy was determined so as to administer 80% of the irradiation prescription dose to the deepest lung-chest wall border, which was usually located at the internal mammary lymph node chain. An individualized custom bolus was prepared to compensate for a chest wall thinner than the prescription depth by meticulously measuring the chest wall thickness at 1 cm{sup 2} intervals on the planning CT images. A second planning CT was obtained overlying the individualized custom bolus for each patient's chest wall. 3-D treatment planning was performed using ADAC-Pinnacle{sup 3} for all patients with and without bolus, NTCPs based on 'the Lyman-Kutcher' model were analyzed and the mean, maximum, minimum doses, V{sub 50} and V{sub 95} for the heart and lungs were computed. The average NTCPs in the ipsilateral lung showed a statistically significant reduction (p<0.01), from 80.2{+-}3.43% to 47.7{+-}4.61%, with the use of the individualized custom boluses. The mean lung irradiation dose to the ipsilateral lung was also significantly reduced by about 430 cGy from 2757 cGy to 2,327 cGy (p<0.01). The V{sub 50} and V{sub 95} in the ipsilateral lung markedly decreased from the averages of 54.5 and 17.4% to 45.3 and 11.0%, respectively. The V{sub 50} and V{sub 95} in the heart also decreased from the averages of 16.8 and 6.1% to 9.8% and 2.2%, respectively. The NTCP in the contralateral lung and the heart were 0%, even for the cases with no bolus

  15. Chasing Science at Sea: Racing Hurricanes, Stalking Sharks, and Living Undersea With Ocean Experts

    Lee, Cindy

    2008-12-01

    Ellen Prager's new book, Chasing Science at Sea, is a personal account of why fieldwork is so important in many areas of ocean science, and how exciting that fieldwork can be. Prager has interwoven her own story of studying carbonates at the interface between biology and geology with stories from friends and colleagues. Storm stories and up-close-and-personal encounters with ocean creatures such as reef squid, marine iguanas, and whales abound. Throughout the book, she emphasizes the idea that the combination of observations and serendipity plays a critical role in science, and she gives examples of where this combination has led to especially important discoveries (e.g., that of hydrothermal vent organisms).

  16. Cardiovascular effects of intravenous bolus administration and infusion of ketamine-midazolam in isoflurane-anesthetized dogs.

    Jacobson, J D; Hartsfield, S M

    1993-10-01

    Cardiovascular effects of IV administered ketamine (10 mg/kg) and midazolam (0.5 mg/kg) were determined in 12 healthy isoflurane-anesthetized (1.7% end-tidal concentration) dogs. Six dogs received a ketamine-midazolam combination (K-M) as a bolus over 30 seconds and 6 dogs received K-M as an infusion over 15 minutes. Ketamine-midazolam combination as a bolus and an infusion caused early significant (P dogs of the infusion group and returned to the baseline value near the end of the study. One dog died after K-M bolus administration. Mean maximal decreases from baseline for systemic blood pressure, cardiac index, and stroke index were significantly (P dogs of the bolus group than in dogs of the infusion group; therefore, cardiovascular effects of K-M after infusion were less severe than those after bolus. Base excess and pHa decreased significantly (P infusion group, although similar changes occurred in both groups. Four dogs were maintained with 1.7% end-tidal isoflurane to determine temporal effects of isoflurane; these dogs did not receive K-M. Increases in heart rate, cardiac index, stroke index, and left and right ventricular stroke work indexes were significant (P < 0.05) at various sample collection intervals, particularly during the later stages of the study. Isoflurane anesthesia effectively blocked the cardiostimulatory properties of K-M.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8250398

  17. Feasibility of a fixed scan delay technique using a previous bolus tracking technique data for dynamic hepatic CT

    Objective: To compare the quality of contrast enhancement and hepatic CT images acquired using bolus tracking technique at two different time points and those acquired with fixed scan delay technique using a previous bolus tracking data. Materials and methods: Fifty patients who underwent 3 different hepatic CT exams (25-s fixed injection of 600 mg iodine (I)/kg or 100 mL of 370 mg I/mL nonionic contrast medium) were enrolled. The first and second exams were performed with a bolus tracking technique. The third exam was performed with a fixed scan delay technique using the first exam data. Differences in attenuation values in the abdominal organs were examined and evaluated visually on hepatic arterial phase images. Results: There was no significant difference in the mean 50-HU threshold times between the first and second bolus tracking exams with intra-patient differences between them (1.3 ± 0.9 s). No significant intra-patient differences were noted in organ attenuation and visual evaluation on hepatic arterial phase images between the 3 exams. Conclusion: The fixed scan delay technique using a previous bolus tracking data is feasible for hepatic CT exams to follow up hepatocellular carcinoma.

  18. Note: Utilization of polymer gel as a bolus compensator and a dosimeter in the near-surface buildup region for breast-conserving therapy

    Tangential beam radiotherapy is routinely used for radiation therapy after breast conserving surgery. A tissue-equivalent bolus placed on the irradiated area shifts the depth of the dose distribution; this bolus provides uniform dose distribution to the breast. The gel bolus made by the BANG-Pro® polymer gel and in an oxygen non-transmission pack was applicable as a dosimeter to measure dose distribution in near-surface buildup region. We validated the use of the gel bolus to improve in the whole-breast/chest wall, including the near-surface buildup region

  19. Note: Utilization of polymer gel as a bolus compensator and a dosimeter in the near-surface buildup region for breast-conserving therapy

    Fuse, Hiraku, E-mail: fuseh@ipu.ac.jp; Inohira, Masaya; Kawamura, Hiraku; Fujisaki, Tatsuya [Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, Inashiki-gun, Ibaraki 300-0331 (Japan); Shinoda, Kazuya [Graduate School of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, Ibaraki (Japan); Department of Radiological Technology, Tsukuba Medical Center Hospital, Tsukuba (Japan); Miyamoto, Katsumi [Department of Radiological Technology, Tsukuba Medical Center Hospital, Tsukuba (Japan); Sakae, Takeji [Faculty of Medicine, University of Tsukuba, Tsukuba (Japan)

    2015-09-15

    Tangential beam radiotherapy is routinely used for radiation therapy after breast conserving surgery. A tissue-equivalent bolus placed on the irradiated area shifts the depth of the dose distribution; this bolus provides uniform dose distribution to the breast. The gel bolus made by the BANG-Pro{sup ®} polymer gel and in an oxygen non-transmission pack was applicable as a dosimeter to measure dose distribution in near-surface buildup region. We validated the use of the gel bolus to improve in the whole-breast/chest wall, including the near-surface buildup region.

  20. Study of the usefulness on liver CT using intermittent bolus injection method

    Usefulness on the liver CT using intermittent bolus injection method of contrast media (IM-CE) was studied in 108 hepatic space occupying lesions, particularly to analyze hepatocellular carcinoma (HCC). Scans were obtained before, 20∼30 (arterial phase) and 60 seconds (parenchymal phase) after intravenous bolus injection of 65%-diatrizoate (angiografin) or 300 mg I-iopamidol (iopamiron 300), and in case of necessity, added 3∼15 minutes (late phase) after all injections of contrast media. These scans imaging the features of hepatic mass provided us much useful information. Early enhancement of the arterial phase, and early wash out of the parenchymal phase and delayed ring enhancement of the capsule improved the rates of detection to 96%, 60%, and 49% respectively in case of HCC. Especially. at the small HCC (less than 2cm in diameter), these rates were 89%, 50%, and 28% respectively. Combination of these 3 findings suggested the possibility of HCC in comparison with other hepatic mass. The rate of accurate diagnosis of HCC by this IM-CE was 81%. Thus IM-CE CT provides the useful information in diagnosis of hepatic mass and should be considered as the routine examination of hepatic mass. (author)

  1. Bolus timing in high-pitch CT angiography of the aorta

    Beeres, Martin, E-mail: beeres@gmx.net [Clinic of the Goethe University, Department of Diagnostic and Interventional Radiology, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Loch, Matthias, E-mail: MatthiasLoch@gmx.net [Clinic of the Goethe University, Department of Diagnostic and Interventional Radiology, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Schulz, Boris, E-mail: boris.schell@googlemail.com [Clinic of the Goethe University, Department of Diagnostic and Interventional Radiology, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Kerl, Matthias, E-mail: matthias.kerl@gmail.com [Clinic of the Goethe University, Department of Diagnostic and Interventional Radiology, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Al-Butmeh, Firas, E-mail: Firas.Albutmeh@gmail.com [Clinic of the Goethe University, Department of Diagnostic and Interventional Radiology, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Bodelle, Boris, E-mail: bbodelle@googlemail.com [Clinic of the Goethe University, Department of Diagnostic and Interventional Radiology, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Herrmann, Eva, E-mail: Herrmann@Med.Uni-Frankfurt.de [Clinic of the Goethe University, Department of Biostatistics, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Gruber-Rouh, Tatjana, E-mail: tatjanagruber2004@yahoo.de [Clinic of the Goethe University, Department of Diagnostic and Interventional Radiology, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Lee, Clara, E-mail: Clara.Lee@kgu.de [Clinic of the Goethe University, Department of Diagnostic and Interventional Radiology, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Jacobi, Volkmar, E-mail: Volkmar.Jacobi@kgu.de [Clinic of the Goethe University, Department of Diagnostic and Interventional Radiology, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Vogl, Thomas J., E-mail: T.Vogl@em.uni-frankfurt.de [Clinic of the Goethe University, Department of Diagnostic and Interventional Radiology, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); and others

    2013-06-15

    Objective: To investigate the bolus geometry in high-pitch CT angiography (CTA) of the aorta without ECG synchronisation in comparison to single-source CT. Methods: Overall 160 consecutive patients underwent CTA either in conventional single-source mode with a pitch of 1.2 (group 1), or in dual-source mode with a pitch of 3.0 (groups 2, 3 and 4) using different contrast media timings with bolus triggering at 140 HU (5 s, group 1; 10 s, group 2; 12 s, group 3; 14 s, group 4). Contrast material, saline flush, flow rate and kV/mAs settings were kept equal for optimum comparability. Aortic attenuation was measured along the z-axis of the patient at different anatomic landmarks and subjective image quality was compared. Results: The most homogeneous enhancement of the aorta was reached with a delay of 10 s after reaching the trigger threshold. The imaging length was not significantly different, but the examination time was significantly (p < 0.001) shorter in the high-pitch group (7.7 s vs. 1.7 s for group 1 vs. 2, 3 and 4). Conclusion: In high-pitch CT angiography using a start delay of 10 s after a trigger threshold of 140 HU in the descending aorta is reached, a homogenous contrast along the z-axis is accomplished.

  2. Ocular dynamics of Garcinia cola (Heckel on healthy volunteers following bolus ingestion

    S. A. Igwe

    2007-01-01

    Full Text Available Garcinia cola Heckel, an angiospermae belonging to the  family Guttiferae, is known in commerce as bitter cola. It is a plant found in the West African subregion, mostly in moist conditions, and often in association with Cola acuminata. The seeds are highly valued ingredients in African ethonomedicine. The seeds have several social uses and applications in folk medicine. These seeds are ordinarily chewed by the local people without prescription or restriction. In an in vivo case control study, the effects of Garcinia cola on some visual functions: pupil diameter, near point of convergence (NPC, amplitude of accommodation (AA, intraocular pressure (IOP, visual acuity (VA and habitual phoria; following bolus ingestion of 20 g was undertaken using healthy visually active volunteers. Results showed that bolus ingestion of Garcinia cola constricted the pupil by 68%, reduced the NPC by 28%, increased the AA by 17.8% at peak effect and decreased the intraocular pressure by 31% without affecting the distance and near VA. The lateral phoria at far and near tended towards esophoria. Possibly the miotic effect and reduction in IOP could be of benefit to patients with raised IOP where conventional drugs may not be effective. Also it is possible that the effects on phoria could be exploited in oculomotor function in combination with visual training.

  3. The Effect of Bolus Volume on Hyoid Kinematics in Healthy Swallowing

    Ahmed Nagy

    2014-01-01

    Full Text Available Hyoid movement in swallowing is biomechanically linked to closure of the laryngeal vestibule for airway protection and to opening of the upper esophageal sphincter. Studies suggest that the range of hyoid movement is highly variable in the healthy population. However, other aspects of hyoid movement such as velocity remain relatively unexplored. In this study, we analyze data from a sample of 20 healthy young participants (10 male to determine whether hyoid movement distance, duration, velocity, and peak velocity vary systematically with increases in thin liquid bolus volume from 5 to 20 mL. The temporal correspondence between peak hyoid velocity and laryngeal vestibule closure was also examined. The results show that maximum hyoid position and peak velocity increase significantly for 20 mL bolus volumes compared to smaller volumes, and that the timing of peak velocity is closely linked to achieving laryngeal vestibule closure. This suggests that generating hyoid movements with increased power is a strategy for handling larger volumes.

  4. A retrospective comparison of smart prep and test bolus multi-detector CT pulmonary angiography protocols

    Optimal arterial opacification is crucial in imaging the pulmonary arteries using computed tomography (CT). This poses the challenge of precisely timing data acquisition to coincide with the transit of the contrast bolus through the pulmonary vasculature. The aim of this quality assurance exercise was to investigate if a change in CT pulmonary angiography (CTPA) scanning protocol resulted in improved opacification of the pulmonary arteries. Comparison was made between the smart prep protocol (SPP) and the test bolus protocol (TBP) for opacification in the pulmonary trunk. A total of 160 CTPA examinations (80 using each protocol) performed between January 2010 and February 2011 were assessed retrospectively. CT attenuation coefficients were measured in Hounsfield Units (HU) using regions of interest at the level of the pulmonary trunk. The average pixel value, standard deviation (SD), maximum, and minimum were recorded. For each of these variables a mean value was then calculated and compared for these two CTPA protocols. Minimum opacification of 200 HU was achieved in 98% of the TBP sample but only 90% of the SPP sample. The average CT attenuation over the pulmonary trunk for the SPP was 329 (SD = ±21) HU, whereas for the TBP it was 396 (SD = ±22) HU (P = 0.0017). The TBP also recorded higher maximum (P = 0.0024) and minimum (P = 0.0039) levels of opacification. This study has found that a TBP resulted in significantly better opacification of the pulmonary trunk than the SPP

  5. Peristaltic Transport of a Rheological Fluid: Model for Movement of Food Bolus Through Esophagus

    Misra, J C

    2011-01-01

    Fluid mechanical peristaltic transport through esophagus has been of concern in the paper. A mathematical model has been developed with an aim to study the peristaltic transport of a rheological fluid for arbitrary wave shapes and tube lengths. The Ostwald-de Waele power law of viscous fluid is considered here to depict the non-Newtonian behaviour of the fluid. The model is formulated and analyzed with the specific aim of exploring some important information concerning the movement of food bolus through the esophagus. The analysis has been carried out by using lubrication theory. The study is particularly suitable for cases where the Reynolds number is small. The esophagus is treated as a circular tube through which the transport of food bolus takes places by periodic contraction of the esophageal wall. Variation of different variables concerned with the transport phenomena such as pressure, flow velocity, particle trajectory and reflux are investigated for a single wave as well as for a train of periodic per...

  6. A retrospective comparison of smart prep and test bolus multi-detector CT pulmonary angiography protocols

    Suckling, Tara [Medical Imaging Department, Tamworth Rural Referral Hospital, Tamworth, New South Wales (Australia); Smith, Tony [University Department of Rural Health, The University of Newcastle, Tamworth, New South Wales (Australia); Reed, Warren [Discipline of Medical Radiation Sciences, The University of Sydney, Lidcombe (Australia); Medical Imaging Department, Tamworth Rural Referral Hospital, Tamworth, New South Wales (Australia)

    2013-06-15

    Optimal arterial opacification is crucial in imaging the pulmonary arteries using computed tomography (CT). This poses the challenge of precisely timing data acquisition to coincide with the transit of the contrast bolus through the pulmonary vasculature. The aim of this quality assurance exercise was to investigate if a change in CT pulmonary angiography (CTPA) scanning protocol resulted in improved opacification of the pulmonary arteries. Comparison was made between the smart prep protocol (SPP) and the test bolus protocol (TBP) for opacification in the pulmonary trunk. A total of 160 CTPA examinations (80 using each protocol) performed between January 2010 and February 2011 were assessed retrospectively. CT attenuation coefficients were measured in Hounsfield Units (HU) using regions of interest at the level of the pulmonary trunk. The average pixel value, standard deviation (SD), maximum, and minimum were recorded. For each of these variables a mean value was then calculated and compared for these two CTPA protocols. Minimum opacification of 200 HU was achieved in 98% of the TBP sample but only 90% of the SPP sample. The average CT attenuation over the pulmonary trunk for the SPP was 329 (SD = ±21) HU, whereas for the TBP it was 396 (SD = ±22) HU (P = 0.0017). The TBP also recorded higher maximum (P = 0.0024) and minimum (P = 0.0039) levels of opacification. This study has found that a TBP resulted in significantly better opacification of the pulmonary trunk than the SPP.

  7. Oscillation and collective conveyor of water-in-oil droplets by microfluidic bolus flow

    Ohmura, Takuya; Kamei, Ken-ichiro; Maeda, Yusuke T

    2015-01-01

    Microfluidic techniques have been extensively developed to realize micro-total analysis systems in a small chip. For microanalysis, the trapping or arranging of objects in a line is a critical step. Physical effects such as inertial lift force have been utilized so far, however, hydrodynamic interaction in a many body system is yet to be explored despite its relevance to pattern formation. Here, we report water-in-oil (W/O) droplets can be transported with sequential order in the grid of one-dimensional array of another large W/O droplets. As each droplet comes close to an interspace of the large droplet array, while exhibiting persistent back-and-forth motion, it is conveyed at a velocity equal to the droplet array. The droplet also makes asymmetric orbit to and from the large droplet behind, suggesting vortex like stream was involved. We confirm the appearance of closed streamlines, which called bolus flow, in numerical simulation based on lattice Boltzmann method. The existence region of bolus flow account...

  8. High bolus tirofiban vs abciximab in acute STEMI patients undergoing primary PCI - The tamip study

    Mohammed A Balghith

    2012-01-01

    Full Text Available Background: Primary percutaneous coronary intervention (PCI has been shown to be an effective therapy for patients with acute myocardial infarction (MI. Glycoprotein (GP IIb/IIIa receptor blockers reduce thrombotic complications in patients undergoing PCI. Most available data relate to Reopro, which has been registered for this indication. GP IIb/IIIa reduce unfavorable outcome in U/A and non ST-elevation myocardial infarction (STEMI patients. Only few studies focused on high dose Aggrastat for STEMI patients in the emergency department (ED before PCI. The aim is to increase the patency during the time awaiting coronary angioplasty in patients with acute MI. Objectives: To study the effect of upfront high bolus dose (HDR of tirofiban on the extent of residual ST segment deviation 1 hour after primary PCI and the incidence of TIMI 3 flow of the infarct-related artery (IRA. Materials and Methods: A randomized, open label, single center study in the ED. A total of 90 patients with acute ST-elevation MI, diagnosed clinically by ECG criteria (ST segment elevation of >2 mm in two adjacent ECG leads, and with an expectation that a patient will undergo primary PCI. Patients were aged 21-85 years and all received heparin 5000 u, aspirin 160 mg, and Plavix 600 mg. Patients were divided in two groups (group I: triofiban high bolus vs group II: Reopro with 45 patients in each group. In group I, high bolus triofiban 25 mcg/kg over 3 min was started in the ED with maintenance infusion of 0.15 mcg/ kg/min continued for 12 hours and transferred to cath lab for PCI. Patients in group II were transferred to cath lab, where a standard dose of Reopro was given with a bolus of 0.25 mcg/kg and maintenance infusion of 0.125 mcg/kg/min over 12 hours. Results: ST segment resolution and TIMI flow were evaluated in both groups before and after PCI. Thirty-five patients (78% enrolled in group I and 29 patients (64% in group II had resolution of ST segment (P-value 0

  9. A biomechanical model of swallowing for understanding the influence of saliva and food bolus viscosity on flavour release

    De Loubens, Clément; Doyennette, Marion; Tréléa, Ioan Cristian; Souchon, Isabelle

    2013-01-01

    After swallowing a liquid or a semi-liquid food product, a thin film responsible for the dynamic profile of aroma release coats the pharyngeal mucosa. The objective of the present article was to understand and quantify physical mechanisms explaining pharyngeal mucosa coating. An elastohydrodynamic model of swallowing was developed for Newtonian liquids that focused on the most occluded region of the pharyngeal peristaltic wave. The model took lubrication by a saliva film and mucosa deformability into account. Food bolus flow rate and generated load were predicted as functions of three dimensionless variables: the dimensionless saliva flow rate, the viscosity ratio between saliva and the food bolus, and the elasticity number. Considering physiological conditions, the results were applied to predict aroma release kinetics. Two sets of conditions were distinguished. The first one was obtained when the saliva film is thin, in which case food bolus viscosity has a strong impact on mucosa coating and on flavour rel...

  10. Myocardial extravascular extracellular volume fraction measurement by gadolinium cardiovascular magnetic resonance in humans: slow infusion versus bolus

    Jones Bobby L

    2011-03-01

    Full Text Available Abstract Background Myocardial extravascular extracellular volume fraction (Ve measures quantify diffuse fibrosis not readily detectable by conventional late gadolinium (Gd enhancement (LGE. Ve measurement requires steady state equilibrium between plasma and interstitial Gd contrast. While a constant infusion produces steady state, it is unclear whether a simple bolus can do the same. Given the relatively slow clearance of Gd, we hypothesized that a bolus technique accurately measures Ve, thus facilitating integration of myocardial fibrosis quantification into cardiovascular magnetic resonance (CMR workflow routines. Assuming equivalence between techniques, we further hypothesized that Ve measures would be reproducible across scans. Methods In 10 volunteers (ages 20-81, median 33 yr, 3 females, we compared serial Ve measures from a single short axis slice from two scans: first, during a constant infusion, and second, 12-50 min after a bolus (0.2 mmol/kg gadoteridol on another day. Steady state during infusion was defined when serial blood and myocardial T1 data varied Results No subject exhibited LGE near the short axis slices where Ve was measured. The Ve range was 19.3-29.2% and 18.4-29.1% by constant infusion and bolus, respectively. In GEE models, serial Ve measures by constant infusion and bolus did not differ significantly (difference = 0.1%, p = 0.38. For both techniques, Ve was strongly related to age (p Conclusion Myocardial Ve can be measured reliably and accurately 12-50 minutes after a simple bolus. Ve measures are also reproducible across CMR scans. Ve estimation can be integrated into CMR workflow easily, which may simplify research applications involving the quantification of myocardial fibrosis.

  11. Management of hypertensive emergencies of pregnancy by hydralazine bolus injection vs continuous drip--a comparative study.

    Begum, Mosammat Rashida; Quadir, Ehsan; Begum, Anowara; Akhter, Sayeba; Rahman, Khalilur

    2002-01-01

    This prospective study was conducted at Dhaka Medical College and Hospital, Bangladesh. The objective was to identify the time required to control high blood pressure levels in obstetric patients by injection of hydralazine in a bolus intravenous dose vs continuous drip. Seventy-seven patients with eclampsia and hypertensive emergencies comprised the target population. Patients were managed either by hydralazine drip in normal saline (existing official protocol, n = 33) or hydralazine bolus injection (as experiment, n = 44) until diastolic blood pressure fell to 90-95 mmHg. Results were compared. Student's t-test was done for statistical significance, and a P value of hypertensive emergencies in pregnancy. PMID:12466730

  12. Arrowwood National Wildlife Refuge, Chase Lake National Wildlife Refuge, Half-Way Lake Easement Refuge, Johnson Lake Easement Refuge : Narrative report : Calendar year - 1971

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Arrowwood NWR (including Chase Lake NWR and the easement refuges) outlines Refuge accomplishments during the 1971 calendar year....

  13. A CHASE domain containing protein kinase OsCRL4, represents a new AtCRE1-like gene family in rice

    韩秋敏; 姜华武; 齐晓朋; 丁洁; 吴平

    2004-01-01

    AtCRE1 is known to be a cytokinin receptor inArabidopsis. The AtCRE1 protein contains CHASE domain at the N-terminal part, followed by a transmitter (histidine kinase) domain and two receiver domains. The N-terminal CHASE domain of AtCRE1 contains putative recognition sites for cytokinin. Five CHASE domains containing proteins were found in rice, OsCRLla, OsCRLlb, OsCRL2, OsCRL3, and OsCRL4. OsCRL1a, OsCRL1b, OsCRL2 and OsCRL3 contain the four domains existing in CRE1, whereas OsCRL4 only contains the CHASE domain and a putative Ser/Thr protein kinase domain The authors cloned the encoding gene OsCRL4 and found that it represents a new member of the cytokinin receptor protein in rice.

  14. Allocation and residence time of photosynthetic products in a boreal forest using a low-level 14C pulse-chase labeling technique

    Carbone, MS; Czimczik, CI; McDuffee, KE; Trumbore, SE

    2007-01-01

    Much of our understanding about how carbon (C) is allocated in plants comes from radiocarbon (14C) pulse-chase labeling experiments. However, the large amounts of 14C required for decay-counting mean that these studies have been restricted for the most part to mesocosm or controlled laboratory experiments. Using the enhanced sensitivity for 14C detection available with accelerator mass spectrometry (AMS), we tested the utility of a low-level 14C pulse-chase labeling technique for quantifying ...

  15. Changes in thymidylate synthase mRNA in blood leukocytes from patients with colorectal cancer after bolus administration of 5-fluorouracil

    Ehrnrooth, E; Sørensen, B; Poulsen, J H;

    2000-01-01

    5-fluorouracil (5-FU) is considered the standard antineoplastic drug of choice for metastatic colorectal cancer. It has been suggested that 5-FU administered as bolus infusion is cytotoxic mainly through an RNA damaging effect. We investigated the effect of i.v. bolus 5-FU 500-600 mg/m2 on the 5-FU...

  16. The eCHASE System for Cross-border Use of European Multimedia Cultural Heritage Content in Education and Publishing

    Addis, M. J.; Hafeez, S; Prideaux, D.; Lowe, R.; Lewis, P H; K.; Martinez; Sinclair, P. A. S.

    2006-01-01

    Europe’s digital cultural heritage content has tremendous exploitation potential in applications such as Education, Publishing, e-Commerce, Public-Access and Tourism. Value is hugely amplified if the content can be aggregated repurposed and distributed at a European level. The eCHASE project seeks to demonstrate that public-private partnerships between content holders and commercial service providers can create new services and a sustainable business based on access and exploitation of digita...

  17. The regeneration of a multi-ethnic mixed-use area: The case of Robin Hood Chase

    Ian Bentley; Georgia Butina Watson

    1997-01-01

    Urban designers show increasing interest in promoting community participation in urban regeneration and especially housing regeneration. However, effective participation has proved difficult in multi-ethnic mixed-use areas, with their wide range of different (and often conflicting) interest groups. This paper, presented in case-study form, analyses a project in one such area: the Robin Hood Chase local centre in St. Ann’s area of Nottingham. It pays particular attention to the identification ...

  18. Evaluation of T2* change in hollow fiber dialyzer after bolus injection of gadopentetate dimeglumine

    It has been demonstrated in a simulation that diffusion is an important component in determining T2* contrast. When a high-susceptibility agent permeates from intravascular to extracellular space, the changes in its spatial distribution affect the signal intensity of T2*-weighted images so as to potentially represent a diffusion process. To experimentally demonstrate the effects of permeation on T2*-weighted images, we assessed the dynamic changes in T2* signal after a bolus injection of Gd-DTPA (Magnevist: Schering) solution into a hollow fiber dialyzer as a phantom of intravascular and extracellular space. The signal intensity of the hollow fiber dialyzer in gradient-echo images was compared with that in spin-echo images. (author)

  19. Bolus tracking with nanofilter-based multispectral videography for capturing microvasculature hemodynamics

    Najiminaini, Mohamadreza; Kaminska, Bozena; St. Lawrence, Keith; Carson, Jeffrey J. L.

    2014-04-01

    Multispectral imaging is a highly desirable modality for material-based analysis in diverse areas such as food production and processing, satellite-based reconnaissance, and biomedical imaging. Here, we present nanofilter-based multispectral videography (nMSV) in the 700 to 950 nm range made possible by the tunable extraordinary-optical-transmission properties of 3D metallic nanostructures. Measurements made with nMSV during a bolus injection of an intravascular tracer in the ear of a piglet resulted in spectral videos of the microvasculature. Analysis of the multispectral videos generated contrast measurements representative of arterial pulsation, the distribution of microvascular transit times, as well as a separation of the venous and arterial signals arising from within the tissue. Therefore, nMSV is capable of acquiring serial multispectral images relevant to tissue hemodynamics, which may have application to the detection and identification of skin cancer.

  20. Phase II study of simultaneous radiation therapy, continuous infusion, 5-FU and bolus mitomycin-C

    This paper presents preliminary experience in the treatment of 110 patients with different types of neoplasms, who have been treated with a combination of radiation, continuous infusion of 5-FU and bolus Mitomycin-C. The patients selected for this particular mode of therapy were those with carcinomas of the anal canal, esophagus and advanced carcinomas of the head and neck, cervix, pancreas, rectum, lung or bladder. The results with carcinomas of the lung with a variety of non-small cell types, adenocarcinomas of the pancreas, rectum and stomach and transitional-cell carcinomas of the bladder, were disappointing. Although stabilization of disease has been achieved in a number of patients, complete responses seem to be anecdotal

  1. Determination of the pulmonary hypertension by means of the method of the first bolus passage

    The patients suffering from pulmonary hypertension have been examined by the method of the first bolus passage of the isotope administered in the elbow vein (15-20 mCi Tc 99m-Pertechnetat). Placing the camera over the heart the movement of the labelled substance in the heart cavities has been detected. On the basis of these findings and in accordance with the clinical and haemodynamical examinations the severity of the disease has been classified into 3 stages. At the evaluation of the obtained results also other important haemodynamical characteristics of the disease could be defined by calculation. The use of these methods in the everyday clinical routine work is recommended. (author)

  2. Rate of chase-promoted hydrolysis of ATP in the high affinity catalytic site of beef heart mitochondrial ATPase

    Incubation of [γ-32P]ATP with a molar excess of the soluble, homogeneous ATPase from beef heart mitochondria (F1) results in binding of substrate primarily in a single, very high affinity catalytic site and in a slow rate of hydrolysis characteristic of single site catalysis. Subsequent addition of millimolar concentrations of nonradioactive ATP as a cold chase, sufficient to fill catalytic sites on the enzyme, results in an acceleration of hydrolysis of bound radioactive ATP of as much as 106-fold, that is to V/sub max/ rates. For this reason, it was proposed that the high affinity catalytic site is a normal catalytic site on the molecule. This paper shows, in experiments with a rapid mixing-chemical quench apparatus, that hydrolysis of ATP bound in the high affinity catalytic site is accelerated to V/sub max/ rates following addition of 5 μM ATP as a cold chase. Hydrolysis of bound ATP appears to precede that of the chase. The weight of the available evidence continues to support the original suggestion that the high affinity catalytic site of beef heart F1 is a normal catalytic site

  3. Individualized chest wall compensating bolus for electron irradiation following mastectomy: an ultrasound approach

    A-mode ultrasound is used in a procedure to construct individualized tissue compensating bolus for electron beam irradiation of the chest wall, where the thickness of tissues over the lung may vary by as much as 3 cm. Electron energies corresponding to the thickest tissues in the field would normally cause lung tissues beneath the thinner regions to receive the full tumor dose. The problem is made more serious by the fact that electron ranges in lung are 2-3 times greater than in muscle. We feel that some form of individualized compensation is necessary for patients with large variations in chest wall thickness within a given electron treatment field. The A-Scan procedure is particularly suited to deliniation of the pleura-lung interface because of the strong identifiable reflection from this discontinuity. In the first approach, a moldable gelatanous bolus material, mixed to transmit ultrasound at 5 MHz with a velocity equal to the speed of sound in muscle, is placed on the chest wall covering the entire field. The thickness of the compensating material is then reduced at each point in the field so that the total thickness (muscle plus compensator) indicated by the A-scan is everywhere the same as the chosen maximum treatment depth. Because the compensator has nearly the same electron stopping power as muscle, the compensated chest wall is now uniform in thickness over the entire field. In the second approach, we sacrifice the one-step advantages of using sonically transparent compensator material in order to obtain a more rugged and rapid setting compensator. Four patients have been treated with no evidence of pneumonitis. The more elegant combination of these two approaches awaits the development of rugged materials which are both quick setting and sonically transparent

  4. Use of 3D printers to create a patient-specific 3D bolus for external beam therapy.

    Burleson, Sarah; Baker, Jamie; Hsia, An Ting; Xu, Zhigang

    2015-01-01

    The purpose of this paper is to demonstrate that an inexpensive 3D printer can be used to manufacture patient-specific bolus for external beam therapy, and to show we can accurately model this printed bolus in our treatment planning system for accurate treatment delivery. Percent depth-dose measurements and tissue maximum ratios were used to determine the characteristics of the printing materials, acrylonitrile butadiene styrene and polylactic acid, as bolus material with physical density of 1.04 and 1.2 g/cm3, and electron density of 3.38 × 10²³ electrons/cm3 and 3.80 × 10²³ electrons/ cm3, respectively. Dose plane comparisons using Gafchromic EBT2 film and the RANDO phantom were used to verify accurate treatment planning. We accurately modeled a printing material in Eclipse treatment planning system, assigning it a Hounsfield unit of 260. We were also able to verify accurate treatment planning using gamma analysis for dose plane comparisons. With gamma criteria of 5% dose difference and 2 mm DTA, we were able to have 86.5% points passing, and with gamma criteria of 5% dose difference and 3 mm DTA, we were able to have 95% points passing. We were able to create a patient-specific bolus using an inexpensive 3D printer and model it in our treatment planning system for accurate treatment delivery. PMID:26103485

  5. Low-dose esmolol bolus reduces seizure duration during electroconvulsive therapy: a double-blind, placebo-controlled study

    W.W. van den Broek (Walter); A.F. Leentjens; A. Kusuma (Ari); J.A. Bruijn (Jan); P.G.H. Mulder (Paul)

    1999-01-01

    textabstractWe have measured the effect of a bolus dose of esmolol 80 mg i.v. on heart rate, and systolic (SAP), diastolic (DAP) and mean (MAP) arterial pressures during electroconvulsive therapy (ECT). We also assessed seizure duration using both the cuff method and tw

  6. Implementation of a split-bolus single-pass CT protocol at a UK major trauma centre to reduce excess radiation dose in trauma pan-CT

    Aim: To quantify the dose reduction and ensure that the use of a split-bolus protocol provided sufficient vascular enhancement. Materials and methods: Between 1 January 2014 and 31 May 2014, both split bolus and traditional two-phase scans were performed on a single CT scanner (SOMATOM Definition AS+, Siemens Healthcare) using a two-pump injector (Medrad Stellant). Both protocols used Siemens' proprietary tube current and tube voltage modulation techniques (CARE dose and CARE kV). The protocols were compared retrospectively to assess the dose–length product (DLP), aortic radiodensity at the level of the coeliac axis and radiodensity of the portal vein. Results: There were 151 trauma CT examinations during this period. Seventy-eight used the split-bolus protocol. Seventy-one had traditional two-phase imaging. One patient was excluded as they were under the age of 18 years. The radiodensity measurements for the portal vein were significantly higher (p<0.001) in the split-bolus protocol. The mean aortic enhancement in both protocols exceeded 250 HU, although the traditional two-phase protocol gave greater arterial enhancement (p<0.001) than the split-bolus protocol. The split-bolus protocol had a significantly lower (p<0.001) DLP with 43.5% reduction in the mean DLP compared to the traditional protocol. Conclusion: Split-bolus CT imaging offers significant dose reduction for this relatively young population while retaining both arterial and venous enhancement. -- Highlights: •We implemented a split bolus pan-CT protocol for trauma CT. •We compared the radiation dose and vascular enhancement of the split bolus protocol to a traditional two phase protocol. •The split bolus protocol had a 43.5% reduction in mean DLP

  7. Care-bolus tracking systems in multislice-helical computed tomography - a new method in the screening of cardiovascular failure?

    Purpose. Recently bolus tracking systems were developed to improve the timing of intravenous contrast media application in helical computed tomography. We investigated the benefit of this new method as a parameter of the cardiac function.Material and methods. Retrospective analysis of 64 patients which incidentally underwent bolus triggered contrast enhanced helical CT and invasive investigation of the heart within one week. All examinations were performed on the CT scanner Somatom Plus 4 Volume Zoom (Siemens Corp., Forchheim, Germany) using the C.A.R.E. trademark Bolus software. This performs repetitive low- dose test scans (e.g. for the abdomen: 140 kV, 20 mA, TI 0,5 s) and measures the Hounsfield attenuation (increase over the baseline) in a preselected region of interest. The displayed increase of vascular density over the time after peripheral contrast media injection (75 ml Iopromid (300 mg/ml), 2 ml/s) was categorised to three types: (a) rapid increase, (b) deceleration before a 100 HE threshold was reached and (c) one or more peaks. The findings of the invasive investigation of the heart were correlated to the findings of the bolus-tracking measurements.Results. The examinations were categorized as follows: 19 type A, 34 type B, 11 type C. We found a high significant correlation between the type of the Hounsfield attenuation and systolic pressure in the left ventricle. There was no correlation between the type of the Hounsfield attenuation and the diastolic pressure in the left ventricle, the pressures related to the right ventricle or the ejection fraction. The bolus- tacking system showed a sensitivity of 53, a specificity of 82, an accuracy of 70%, a positive predictive value of 70% and a negative predictive value of 70% in detection of left heart failure.Conclusion. The bolus tracking system C.A.R.E.-bolus copyright often shows atypical Hounsfield attenuation in cases of cardiac failure but is not suitable as a screening method of the cardiopulmonary

  8. Degradation dynamics of microRNAs revealed by a novel pulse-chase approach.

    Marzi, Matteo J; Ghini, Francesco; Cerruti, Benedetta; de Pretis, Stefano; Bonetti, Paola; Giacomelli, Chiara; Gorski, Marcin M; Kress, Theresia; Pelizzola, Mattia; Muller, Heiko; Amati, Bruno; Nicassio, Francesco

    2016-04-01

    The regulation of miRNAs is critical to the definition of cell identity and behavior in normal physiology and disease. To date, the dynamics of miRNA degradation and the mechanisms involved in remain largely obscure, in particular, in higher organisms. Here, we developed a pulse-chase approach based on metabolic RNA labeling to calculate miRNA decay rates at genome-wide scale in mammalian cells. Our analysis revealed heterogeneous miRNA half-lives, with many species behaving as stable molecules (T1/2> 24 h), while others, including passenger miRNAs and a number (25/129) of guide miRNAs, are quickly turned over (T1/2= 4-14 h). Decay rates were coupled with other features, including genomic organization, transcription rates, structural heterogeneity (isomiRs), and target abundance, measured through quantitative experimental approaches. This comprehensive analysis highlighted functional mechanisms that mediate miRNA degradation, as well as the importance of decay dynamics in the regulation of the miRNA pool under both steady-state conditions and during cell transitions. PMID:26821571

  9. Sperm whale predator-prey interactions involve chasing and buzzing, but no acoustic stunning.

    Fais, A; Johnson, M; Wilson, M; Aguilar Soto, N; Madsen, P T

    2016-01-01

    The sperm whale carries a hypertrophied nose that generates powerful clicks for long-range echolocation. However, it remains a conundrum how this bizarrely shaped apex predator catches its prey. Several hypotheses have been advanced to propose both active and passive means to acquire prey, including acoustic debilitation of prey with very powerful clicks. Here we test these hypotheses by using sound and movement recording tags in a fine-scale study of buzz sequences to relate the acoustic behaviour of sperm whales with changes in acceleration in their head region during prey capture attempts. We show that in the terminal buzz phase, sperm whales reduce inter-click intervals and estimated source levels by 1-2 orders of magnitude. As a result, received levels at the prey are more than an order of magnitude below levels required for debilitation, precluding acoustic stunning to facilitate prey capture. Rather, buzzing involves high-frequency, low amplitude clicks well suited to provide high-resolution biosonar updates during the last stages of capture. The high temporal resolution helps to guide motor patterns during occasionally prolonged chases in which prey are eventually subdued with the aid of fast jaw movements and/or buccal suction as indicated by acceleration transients (jerks) near the end of buzzes. PMID:27340122

  10. 'Chasing the Dragon' - imaging of heroin inhalation leukoencephalopathy

    Hagel, J. [Vancouver General Hospital, Dept. of Radiology, Vancouver, British Columbia (Canada)]. E-mail: jeff_hagel@hotmail.com; Andrews, G. [UBC Hospital, Dept. of Radiology, Vancouver, British Columbia (Canada); Vertinsky, T. [Vancouver General Hospital, Dept. of Radiology, Vancouver, British Columbia (Canada); Heran, M.K.S. [Vancouver General Hospital, Div. of Neuroradiology, Vancouver, British Columbia (Canada); Keogh, C. [BC Cancer Agency, Dept. of Radiology, Vancouver, British Columbia (Canada)

    2005-10-15

    'Chasing the dragon' refers to the inhalation of heroin pyrolysate vapors produced when the freebase form of heroin is heated. Inhalation of these vapors can result in a rare toxic spongiform leukoencephalopathy. The patients may progress through 3 defined clinical stages, with one-quarter reaching the terminal stage, which invariably leads to death. Imaging and, in particular, magnetic resonance imaging (MRI) demonstrates white matter findings that are felt to be specific for this entity and essential in its early diagnosis. We present the typical imaging findings in a pictorial essay format, using images taken from 9 patients who presented within an 18-month period at UBC-affiliated hospitals. These findings include low computed tomography (CT) attenuation and high T2 MRI signal most commonly in the posterior cerebral and cerebellar white matter, cerebellar peduncles, splenium of the corpus callosum, and posterior limb of the internal capsules. In addition, there is often selective, symmetric involvement of the corticospinal tract, the medial lemniscus, and the tractus solitarius. We also present the variable diffusion-weighted imaging arid apparent diffusion coefficient findings from 4 of our patients, which to our knowledge, have not been described in the literature. (author)

  11. Degradation dynamics of microRNAs revealed by a novel pulse-chase approach

    Marzi, Matteo J.; Ghini, Francesco; Cerruti, Benedetta; de Pretis, Stefano; Bonetti, Paola; Giacomelli, Chiara; Gorski, Marcin M.; Kress, Theresia; Pelizzola, Mattia; Muller, Heiko; Amati, Bruno; Nicassio, Francesco

    2016-01-01

    The regulation of miRNAs is critical to the definition of cell identity and behavior in normal physiology and disease. To date, the dynamics of miRNA degradation and the mechanisms involved in remain largely obscure, in particular, in higher organisms. Here, we developed a pulse-chase approach based on metabolic RNA labeling to calculate miRNA decay rates at genome-wide scale in mammalian cells. Our analysis revealed heterogeneous miRNA half-lives, with many species behaving as stable molecules (T1/2 > 24 h), while others, including passenger miRNAs and a number (25/129) of guide miRNAs, are quickly turned over (T1/2 = 4–14 h). Decay rates were coupled with other features, including genomic organization, transcription rates, structural heterogeneity (isomiRs), and target abundance, measured through quantitative experimental approaches. This comprehensive analysis highlighted functional mechanisms that mediate miRNA degradation, as well as the importance of decay dynamics in the regulation of the miRNA pool under both steady-state conditions and during cell transitions. PMID:26821571

  12. Dopamine D(2) receptor quantification in extrastriatal brain regions using [(123)I]epidepride with bolus/infusion.

    Pinborg, L H; Videbaek, C; Knudsen, G M; Swahn, C G; Halldin, C; Friberg, L; Paulson, O B; Lassen, N A

    2000-06-15

    The iodinated benzamide epidepride, which shows a picomolar affinity binding to dopamine D(2) receptors, has been designed for in vivo studies using SPECT. The aim of the present study was to apply a steady-state condition by the bolus/infusion approach with [(123)I]epidepride for the quantification of striatal and extrastriatal dopamine D(2) receptors in humans. In this way the distribution volume of the tracer can be determined from a single SPECT image and one blood sample. Based on bolus experiments, an algorithm using conventional convolution arguments for prediction of the outcome of a bolus/infusion (B/I) experiment was applied. It was predicted that a B/I protocol with infusion of one-third of the initial bolus per hour would be appropriate. Steady-state conditions were attained in extrastriatal regions within 3-4 h but the infusion continued up to 7 h in order to minimize the significance of individual differences in plasma clearance and binding parameters. A steady-state condition, however, could not be attained in striatal brain regions using a B/I protocol of 20 h, even after 11 h. Under near steady-state conditions a striatal:cerebellar ratio of 23 was demonstrated. Epidepride has a unique signal-to-noise ratio compared to [(123)I]IBZM but present difficulties for steady-state measurements of striatal regions. The bolus/infusion approach is particularly feasible for quantification of the binding potential in extrastriatal regions. PMID:10819910

  13. Geology and hydrogeology of Naval Air Station Chase Field and Naval Auxiliary Landing Field Goliad, Bee and Goliad counties, Texas

    Snyder, G.L.

    1995-01-01

    The geologic formations that crop out near Naval Air Station Chase Field and Naval Auxiliary Landing Field Goliad military bases consist of fluvial to fluvial-deltaic sediments of Tertiary and Quaternary age. These formations include the Fleming and Goliad Formations of Miocene age, Lissie Formation of Pleistocene age, fluvial terrace deposits of Pleistocene to Holocene age, and alluvium of Holocene age. The lithology of these formations consists of sand, sandstone, silt, and clay, with lesser amounts of gravel and caliche in the outcrops. The freshwater aquifers underlying the study area are the unconfined Evangeline (watertable) aquifer, comprising the upper sandy parts of the Fleming Formation and Goliad Formation, and confined Fleming aquifers, comprising the thick sandstone beds of the Fleming Formation. Both military bases withdraw potable water from one of the confined aquifers. At Naval Air Station Chase Field, the transmissivity and storativity of the confined aquifer where the base withdraws its public water supply are 1,060 feet squared per day and 1.2xlO4, respectively, as computed from the results of a 74-hour constant-discharge aquifer test. Selected water-quality field measurements of specific conductance, pH, and temperature indicate that each of the three aquifers at Naval Air Station Chase Field are somewhat insulated from one another by the intervening confining units. Large vertical hydraulic-head gradients are present between the unconfined Evangeline aquifer and confined Fleming aquifers at Naval Air Station Chase Field and Naval Auxiliary Landing Field Goliad. These gradients, together with the results of the aquifer test at Naval Air Station Chase Field and assumed characteristics of the confining units, indicate that downward flow of ground water probably occurs from the water-table aquifer to the underlying aquifers. The rate of downward flow between the two confined Fleming aquifers (from A-sand to B-sand) can be approximated using an

  14. A model of emotion game for chasing between virtual humans%一种虚拟人追逐过程中的情绪博弈模型

    卞玉龙; 刘箴

    2012-01-01

    追逐行为在人类社会生活中十分常见,模拟追逐过程中的情绪变化,有助于揭示情绪和运动的关系.在借鉴博弈论的基础上,研究了虚拟人围绕障碍物追逐的情绪博弈模型,依据追逐的剧情,拟定了虚拟人的情绪强度公式,定量描述了虚拟人的速度和体力的变化,提出了追逐过程中虚拟人情绪博弈策略.采用OpenSceneGraph图形库实现了虚拟人追逐动画,实验结果表明,该模型能很好地模拟追逐中虚拟人情绪的变化规律.%Chasing behavior is very common in human social life, and simulation of the emotion variation in a cha-sing process is helpful to reveal the relationship between emotion and motion. An emotion game model for chasing between virtual human around obstacles was studied on the basis of game theory. The formulas of the emotion inten-sities were constructed by a chasing story, and the variation of a virtual human' s speed and energy were quantita-tively described. The emotion game strategy for a chasing process was presented. The chasing behavior animation of a virtual human was realized in an OpenSceneGraph graphic library. The experimental results show that the model can closely simulate the variation of emotion in a chasing process.

  15. ATTENUATION OF HAEMODYNAMIC RESPONSES TO LARYNGOSCOPY AND ENDOTRACHEAL INTUBATION: ROLE OF I.V. BOLUS DOSE OF ESMOLOL HYDROCHLORIDE AND LIGNOCAINE HYDROCHLORIDE : A COMPARATIVE STUDY

    Padma

    2015-09-01

    Full Text Available AIM: The aim of the study is to compare the efficacy of intravenous Bolus dose of Esmolol Hydrochloride and Lignocaine Hydrochloride to attenuate the Haemodynamic responses to Laryngoscopy and Endotracheal intubation. MATERIALS & METHODS : A study of Esmolol hydrochloride and Lignocaine hydrochloride in attenuation of the cardiovascular respons e during Laryngoscopy and intubation was compared in 50 adult patient, undergoing surgery under general anaesthesia. This study was taken in 2 groups. Group - I consists of 25 patients, where Lignocaine hydrochloride 2 mg per kg IV was used for attenuation of cardiovascular response to Laryngoscopy and intubation. Group - II consists of 25 patients where Esmolol hydrochloride 200 mg IV bolus was used as study drug. RESULTS : Results of the present study are consistent with the studies in attenuating haemodyna mic responses to Laryngoscopy and intubation by the use of intravenous bolus dose of 200 mg of Esmolol is superior to Lignocaine hydrochloride. 2mg per kg body weight IV bolus. CONCLUSION : It establishes the usefulness of intravenous bolus dose of Esmolol to attenuate the haemodynamic responses to Laryngoscopy and endotracheal intubation. This study shows the 200 mg of bolus dose of Esmolol hydrochloride is superior to intravenous Lignocaine hydrochloride 2 mg per kg body weight IV bolus to attenuate the ha emodynamic responses to Laryngoscopy and endotracheal intubation. No side effects were noted with Esmolol and Lignocaine hydrochloride

  16. WE-F-16A-05: Use of 3D-Printers to Create a Tissue Equivalent 3D-Bolus for External Beam Therapy

    Burleson, S; Baker, J; Hsia, A; Xu, Z [Stony Brook Medicine, Stony Brook, NY (United States)

    2014-06-15

    Purpose: The purpose of this project is to demonstrate that a non-expensive 3D-printer can be used to manufacture a 3D-bolus for external beam therapy. The printed bolus then can be modeled in our treatment planning system to ensure accurate dose delivery to the patient. Methods: We developed a simple method to manufacture a patient-specific custom 3Dbolus. The bolus is designed using Eclipse Treatment Planning System, contoured onto the patients CT images. The bolus file is exported from Eclipse to 3D-printer software, and then printed using a 3D printer. Various tests were completed to determine the properties of the printing material. Percent depth dose curves in this material were measured with electron and photon beams for comparison to other materials. In order to test the validity of the 3D printed bolus for treatment planning, a custom bolus was printed and tested on the Rando phantom using film for a dose plane comparison. We compared the dose plane measured on the film to the same dose plane exported from our treatment planning system using Film QA software. The gamma-dose distribution tool was used in our film analysis. Results: We compared point measurements throughout the dose plane and were able to achieve greater than 95% passing rate at 3% dose difference and 3 mm distance to agreement, which is our departments acceptable gamma pixel parameters. Conclusion: The printed 3D bolus has proven to be accurately modeled in our treatment planning system, it is more conformal to the patient surface and more durable than other bolus currently used (wax, superflab etc.). It is also more convenient and less costly than comparable bolus from milling machine companies.

  17. WE-F-16A-05: Use of 3D-Printers to Create a Tissue Equivalent 3D-Bolus for External Beam Therapy

    Purpose: The purpose of this project is to demonstrate that a non-expensive 3D-printer can be used to manufacture a 3D-bolus for external beam therapy. The printed bolus then can be modeled in our treatment planning system to ensure accurate dose delivery to the patient. Methods: We developed a simple method to manufacture a patient-specific custom 3Dbolus. The bolus is designed using Eclipse Treatment Planning System, contoured onto the patients CT images. The bolus file is exported from Eclipse to 3D-printer software, and then printed using a 3D printer. Various tests were completed to determine the properties of the printing material. Percent depth dose curves in this material were measured with electron and photon beams for comparison to other materials. In order to test the validity of the 3D printed bolus for treatment planning, a custom bolus was printed and tested on the Rando phantom using film for a dose plane comparison. We compared the dose plane measured on the film to the same dose plane exported from our treatment planning system using Film QA software. The gamma-dose distribution tool was used in our film analysis. Results: We compared point measurements throughout the dose plane and were able to achieve greater than 95% passing rate at 3% dose difference and 3 mm distance to agreement, which is our departments acceptable gamma pixel parameters. Conclusion: The printed 3D bolus has proven to be accurately modeled in our treatment planning system, it is more conformal to the patient surface and more durable than other bolus currently used (wax, superflab etc.). It is also more convenient and less costly than comparable bolus from milling machine companies

  18. The influence of carbon monoxide bolus on the measurement of total haemoglobin mass using the optimized CO-rebreathing method

    The optimized carbon monoxide (CO) rebreathing method (oCOR-method) is routinely used to measure total haemoglobin mass (tHbmass). The tHbmass measure is subject to a test-retest typical error of ∼2%, mostly from the precision of carboxyhaemoglobin (HbCO) measurement. We hypothesized that tHbmass would be robust to differences in the bolus of CO administered during the oCOR-method. Twelve participants (ten males and two females; age 27 ± 6 yr, height 177 ± 11 cm and mass 73.9 ± 12.1 kg) completed the oCOR-method on four occasions. Different bolus of CO were administered (LOW: 0.6 ml kg−1; MED1: 1.0 ml kg−1 and HIGH: 1.4 ml kg−1); to determine the reliability of MED1, a second trial was conducted (MED2). tHbmass was found to be significantly less from the HIGH CO bolus (776 ± 148 g) when compared to the LOW CO (791 ± 149 g) or MED1 CO (788 ± 149 g) trials. MED2 CO was 785 ± 150 g. The measurement of tHbmass is repeatable to within 0.8%, but a small and notable difference was seen when using a HIGH CO bolus (1.4 to 1.9% less), potentially due to differences in CO uptake kinetics. Previously, an improved precision of the oCOR-method was thought to require a higher bolus of CO (i.e. larger ▵%HbCO), as commercial hemoximeters only estimate %HbCO levels to a single decimal place (usually ± 0.1%). With the new hemoximeter used in this study, a bolus of 1.0 ml kg−1 allows adequate precision with acceptable safety. (note)

  19. Radiation dermatitis caused by a bolus effect from an abdominal compression device.

    Connor, Michael; Wei, Randy L; Yu, Suhong; Sehgal, Varun; Klempner, Samuel J; Daroui, Parima

    2016-01-01

    American Association of Physicists in Medicine (AAPM) Task Group 176 evaluated the dosimetric effects caused by couch tops and immobilization devices. The report analyzed the extensive physics-based literature on couch tops, stereotactic body radiation therapy (SBRT) frames, and body immobilization bags, while noting the scarcity of clinical reports of skin toxicity because of external devices. Here, we present a clinical case report of grade 1 abdominal skin toxicity owing to an abdominal compression device. We discuss the dosimetric implications of the utilized treatment plan as well as post hoc alternative plans and quantify differences in attenuation and skin dose/build-up between the device, a lower-density alternative device, and an open field. The description of the case includes a 66-year-old male with HER2 amplified poorly differentiated distal esophageal adenocarcinoma treated with neoadjuvant chemo-radiation and the use of an abdominal compression device. Radiation was delivered using volumetric modulated arc therapy (VMAT) with 2 arcs using abdominal compression and image guidance. The total dose was 50.4Gy delivered over 40 elapsed days. With 2 fractions remaining, the patient developed dermatitis in the area of the compression device. The original treatment plan did not include a contour of the device. Alternative post hoc treatment plans were generated, one to contour the device and a second with anterior avoidance. In conclusion, replanning with the device contoured revealed the bolus effect. The skin dose increased from 27 to 36Gy. planned target volume (PTV) coverage at 45Gy was reduced to 76.5% from 95.8%. The second VMAT treatment plan with an anterior avoidance sector and more oblique beam angles maintained PTV coverage and spared the anterior wall, however at the expense of substantially increased dose to lung. This case report provides an important reminder of the bolus effect from external devices such as abdominal compression. Special

  20. Continuous versus bolus cardiac output monitoring during or thotopic liver transplantation

    Fang-Ping Bao; Jian Wu

    2008-01-01

    BACKGROUND: Cardiac output monitoring is important for critical patients. This study aimed to determine the delayed response of continuous cardiac output (CCO) thermodilution measurement, whether CCO and bolus cardiac output (BCO) thermodilution agree sufifciently to be used interchangeably, and whether CCO monitoring is reliable for patients undergoing liver transplantation. METHODS:Thirteen patients undergoing liver transplan-tation without veno-venous bypass were studied (37-66 years old, weight 46-75 kg). Continuous and bolus thermodilution measurements were performed at predeifned time points using an "Opti-Q" SvO2/CCO monitor (Abbott Laboratories, North Chicago, IL, USA). Bias and 95% limits of agreement were calculated according to Bland and Altman analysis. The limits of agreement by which two methods are judged to be interchangeable were deifned in advance as ±(13%× BCOmean) L/min. The repeatability and relative error of CCO, and the differences between CCO and the mean of the two measurements were calculated. RESULTS:Cardiac output measurements yielded 196 data pairs with ranges of 1.9 to 17.9 L/min for CCO and 2.1 to 18.3 L/min for BCO. The response time of CCO was delayed in the early phases after caval clamping and after reperfusion. At most of the measurement points, bias and 95%limits of agreement were-0.18±1.91 L/min. 95%limits of agreement did not fall within the predetermined limits of agreement of ±1.14 L/min. The repeatability coefifcient of CCO was 0.36 L/min and the relative error was 4.6±4.7%. The mean difference between CCO and the average of the two methods was-0.09 L/min (0.49 L/min). CONCLUSIONS:In patients undergoing liver transplan-tation, the delayed response of CCO limits its application during the early phases after caval clamping and after reperfusion of the graft. The two methods are not interchangeable even in hemodynamic stability. Continuous thermodilution monitoring, however, is reliable or acceptable for clinical purposes.

  1. Visual processing in rapid-chase systems: Image processing, attention, and awareness

    ThomasSchmidt

    2011-07-01

    Full Text Available Visual stimuli can be classified so rapidly that their analysis may be based on a single sweep of feedforward processing through the visuomotor system. Behavioral criteria for feedforward processing can be evaluated in response priming tasks where speeded pointing or keypress responses are performed towards target stimuli which are preceded by prime stimuli. We apply this method to several classes of complex stimuli. 1 When participants classify natural images into animals or non-animals, the time course of their pointing responses indicates that prime and target signals remain strictly sequential throughout all processing stages, meeting stringent behavioral criteria for feedforward processing (rapid-chase criteria. 2 Such priming effects are boosted by selective visual attention for positions, shapes, and colors, in a way consistent with bottom-up enhancement of visuomotor processing, even when primes cannot be consciously identified. 3 Speeded processing of phobic images is observed in participants specifically fearful of spiders or snakes, suggesting enhancement of feedforward processing by long-term perceptual learning. 4 When the perceived brightness of primes in complex displays is altered by means of illumination or transparency illusions, priming effects in speeded keypress responses can systematically contradict subjective brightness judgments, such that one prime appears brighter than the other but activates motor responses as if it was darker. We propose that response priming captures the output of the first feedforward pass of visual signals through the visuomotor system, and that this output lacks some characteristic features of more elaborate, recurrent processing. This way, visuomotor measures may become dissociated from several aspects of conscious vision. We argue that "fast" visuomotor measures predominantly driven by feedforward processing should supplement "slow" psychophysical measures predominantly based on visual

  2. SR-71B - in Flight with F-18 Chase Aircraft - View from Air Force Tanker

    1996-01-01

    NASA 831, an SR-71B operated by the Dryden Flight Research Center, Edwards, California, cruises over the Mojave Desert with an F/A-18 Hornet flying safety chase. They were photographed on a 1996 mission from an Air Force refueling tanker The F/A-18 Hornet is used primarily as a safety chase and support aircraft at Dryden. As support aircraft, the F-18s are used for safety chase, pilot proficiency and aerial photography. Two SR-71 aircraft have been used by NASA as testbeds for high-speed and high-altitude aeronautical research. The aircraft, an SR-71A and an SR-71B pilot trainer aircraft, have been based here at NASA's Dryden Flight Research Center, Edwards, California. They were transferred to NASA after the U.S. Air Force program was cancelled. As research platforms, the aircraft can cruise at Mach 3 for more than one hour. For thermal experiments, this can produce heat soak temperatures of over 600 degrees Fahrenheit (F). This operating environment makes these aircraft excellent platforms to carry out research and experiments in a variety of areas -- aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic boom characterization. The SR-71 was used in a program to study ways of reducing sonic booms or over pressures that are heard on the ground, much like sharp thunderclaps, when an aircraft exceeds the speed of sound. Data from this Sonic Boom Mitigation Study could eventually lead to aircraft designs that would reduce the 'peak' overpressures of sonic booms and minimize the startling affect they produce on the ground. One of the first major experiments to be flown in the NASA SR-71 program was a laser air data collection system. It used laser light instead of air pressure to produce airspeed and attitude reference data, such as angle of attack and sideslip, which are normally obtained with small tubes and vanes extending into the airstream. One of Dryden's SR-71s was used

  3. Dosimetry characterization and clinical application of Exa skin: Bolus of high of high density for use with photons; Caracterizacion dosimetrica y aplicacion clinica de Exaskin: bolus de alta densidad para uso con fotones

    Ortiz Seidel, M.; Velazquez Miranda, S.

    2013-07-01

    Bolus of high density eXaSkin of density 1.6 g/cm{sub 3} is calculated correctly in the planning systems, is easy to use and generates optimum coupling with the radiation area, at the same time which is easily reproducible in their placement, avoiding the use of electron beams. On the other hand its behavior varies very slightly with the presence of air gaps. (Author)

  4. Optimizing computed tomography pulmonary angiography using right atrium bolus monitoring combined with spontaneous respiration

    CT pulmonary angiography (CTPA) aims to provide pulmonary arterial opacification in the absence of significant pulmonary venous filling. This requires accurate timing of the imaging acquisition to ensure synchronization with the peak pulmonary artery contrast concentration. This study was designed to test the utility of right atrium (RA) monitoring in ensuring optimal timing of CTPA acquisition. Sixty patients referred for CTPA were divided into two groups. Group A (n = 30): CTPA was performed using bolus triggering from the pulmonary trunk, suspended respiration and 70 ml of contrast agent (CA). Group B (n = 30): CTPA image acquisition was triggered using RA monitoring with spontaneous respiration and 40 ml of CA. Image quality was compared. Subjective image quality, average CT values of pulmonary arteries and density difference between artery and vein pairs were significantly higher whereas CT values of pulmonary veins were significantly lower in group B (all P < 0.05). There was no significant difference between the groups in the proportion of subjects where sixth grade pulmonary arteries were opacified (P > 0.05). RA monitoring combined with spontaneous respiration to trigger image acquisition in CTPA produces optimal contrast enhancement in pulmonary arterial structures with minimal venous filling even with reduced doses of CA. (orig.)

  5. Basal or bolus dose, which is the key factor in CSII?

    YANG Nai-long; XUE Bing; LIN Peng

    2006-01-01

    Objective: To observe the value of HbA1c level evaluating the total daily basal insulin dose by continuous subcutaneous insulin infusion (CSII) in 268 patients with type 2 diabetes mellitus. Methods: 5-point capillary blood glucose was monitored in pre- and post-CSII and the insulin dose which could stabilize blood glucose was defmed as the total daily dose of insulin,including basal and bolus total dose. Correlation between HbA1c level and total daily dose of insulin in patients with type 2 diabetes mellitus was analyzed. Correlation between HbA1c level and 5-point capillary blood glucose was also analyzed. Results:Obvious correlation was observed between HbA1c level and the basal total daily dose of insulin if HbA1c was more than 9.3%(r=0.635, P<0.05). The average of 5-point capillary blood glucose was best correlated with HbA1c and fasting blood glucose next best. Conclusion: HbA1c level can forecast basal total daily dose of insulin in CSII.

  6. Optimizing computed tomography pulmonary angiography using right atrium bolus monitoring combined with spontaneous respiration

    Min, Wang; Jian, Li; Rui, Zhai [Jining No. 1 People' s Hospital, Department of Computed Tomography, Jining City, ShanDong Province (China); Wen, Li [Jining No. 1 People' s Hospital, Department of Gastroenterology, Jining, ShanDong (China); Dai, Lun-Hou [Shandong Chest Hospital, Department of Radiology, Jinan, ShanDong (China)

    2015-09-15

    CT pulmonary angiography (CTPA) aims to provide pulmonary arterial opacification in the absence of significant pulmonary venous filling. This requires accurate timing of the imaging acquisition to ensure synchronization with the peak pulmonary artery contrast concentration. This study was designed to test the utility of right atrium (RA) monitoring in ensuring optimal timing of CTPA acquisition. Sixty patients referred for CTPA were divided into two groups. Group A (n = 30): CTPA was performed using bolus triggering from the pulmonary trunk, suspended respiration and 70 ml of contrast agent (CA). Group B (n = 30): CTPA image acquisition was triggered using RA monitoring with spontaneous respiration and 40 ml of CA. Image quality was compared. Subjective image quality, average CT values of pulmonary arteries and density difference between artery and vein pairs were significantly higher whereas CT values of pulmonary veins were significantly lower in group B (all P < 0.05). There was no significant difference between the groups in the proportion of subjects where sixth grade pulmonary arteries were opacified (P > 0.05). RA monitoring combined with spontaneous respiration to trigger image acquisition in CTPA produces optimal contrast enhancement in pulmonary arterial structures with minimal venous filling even with reduced doses of CA. (orig.)

  7. Prevalence of Eosinophilic Esophagitis and Lymphocytic Esophagitis in Adults with Esophageal Food Bolus Impaction.

    Truskaite, Kotryna; Dlugosz, Aldona

    2016-01-01

    Background. The relation of esophageal food bolus impaction (FBI) to eosinophilic esophagitis (EoE) and lymphocytic esophagitis (LyE) is unclear. The aim of this study was to determine the prevalence of EoE and LyE among adults with FBI. Methods. In this retrospective study we analyzed data from all patients referred for gastroscopy during the past 5 years, because of a present or recent episode of FBI. Results. We found 238 patients with FBI (median age 51 (17-96), 71% males). Endoscopic therapy was required in 143 patients. Esophageal biopsies were obtained in 185 (78%) patients. All biopsies were assessed for numbers of eosinophils and lymphocytes. EoE was found in 18% of patients who underwent biopsy. We found 41 patients (22%) who fulfilled the criteria for both EoE and LyE (EoE/LyE). LyE was found in the 9% of patients with FBI. EoE together with EoE/LyE was the leading cause of FBI in patients ≤50 years (64%). GERD was the leading cause of FBI among patients older than 50 years (42%). Conclusions. Our study showed that EoE was the leading cause of FBI in particular among young adults. Our study highlights the need for esophageal biopsies in any patient with FBI. PMID:27547221

  8. Thoracic pathologies on scout views and bolus tracking slices for computed tomographic cerebral angiography

    Groth, M.; Fiehler, J.; Buhk, J.H. [University Medical Center Hamburg-Eppendorf (Germany). Dept. of Diagnostic and Interventional Neuroradiology; Henes, F.O. [University Medical Center Hamburg-Eppendorf (Germany). Dept. of Diagnostic and Interventional Radiology

    2015-08-15

    To evaluate the incidence of additional thoracic pathologic findings (TPF) detected on scout views and corresponding bolus tracking slices (SVBT) for computed tomographic cerebral angiography (CTCA) and to test the reliability and accuracy of these findings. The study collective included 505 consecutive patients who underwent multidetector CTCA. Appendant SVBT of all patients were reviewed for any pathologic findings and patient medical reports were analyzed, if any medical treatment was initiated for the detected pathologic findings. In 18 patients thoracic CT scans were performed in the same session. These were additionally reviewed by two blinded observers to test for intra- and interobserver reliability as well as for accuracy of detecting thoracic pathologies on SVBT. TPF were detected in 165 (33 %) SVBT. The five most common pathologic findings were: pleural effusion, 12 %; pneumonia, 8 %; atelectasis/dystelecatsis, 6 %; pericardial effusion, 2 % and elevated diaphragm, 1 %. For 48 % of these findings medical treatment was initiated. SVBT showed a sensitivity of 53 %, a specificity of 99 %, a positive predictive value of 89 %, a negative predictive value of 94 % and accuracy of 94 % for the detection of TPF. The intraobserver reliability was very good and the interobserver reliability showed moderate agreement. SVBT for CTCA should be reviewed with care by radiologists, since additional TPF can affect patient management. Nevertheless, despite a high specificity of SVBT for detecting TPF, an only moderate sensitivity has to be taken into account.

  9. Longitudinal dispersion of Xenon-133 bolus in the oropharynx and the larynx

    The study aims at confirming that the upper airways (oropharynx) cannot be considered as a simple dead space playing no specific role in the mixing and to establish the transfer function of these airways during inspiration and expiration. The experiments are performed on five healthy subjects. A 133Xe bolus is injected in front of the lips while the subject breathes air at a constant flow rate. The radioactivity is measured during inspiration and expiration by two counter probes in front of the lips and at the level of the upper opening of the trachea. The experimental outputs, under the glottis for inspiration and in front of the lips for expiration, are compared with the responses of a mathematical model which takes into account the longitudinal mixing of gas in the oropharynx and the larynx. This method mades it possible to determine the parameters which the transfer function depends on. Our results suggest that the relationships between the longitudinal dispersion coefficient and the product of the mean axial velocity u by the diameter d or the length L of the upper airways, is linear. The transfer function is the same for the five subjects but the inspiratory and expiratory transfer functions are different

  10. Pixel-by-pixel deconvolution of bolus-tracking data: optimization and implementation

    Sourbron, S.; Dujardin, M.; Makkat, S.; Luypaert, R.

    2007-01-01

    Quantification of haemodynamic parameters with a deconvolution analysis of bolus-tracking data is an ill-posed problem which requires regularization. In a previous study, simulated data without structural errors were used to validate two methods for a pixel-by-pixel analysis: standard-form Tikhonov regularization with either the L-curve criterion (LCC) or generalized cross validation (GCV) for selecting the regularization parameter. However, problems of image artefacts were reported when the methods were applied to patient data. The aim of this study was to investigate the nature of these problems in more detail and evaluate strategies of optimization for routine application in the clinic. In addition we investigated to which extent the calculation time of the algorithm can be minimized. In order to ensure that the conclusions are relevant for a larger range of clinical applications, we relied on patient data for evaluation of the algorithms. Simulated data were used to validate the conclusions in a more quantitative manner. We conclude that the reported problems with image quality can be removed by appropriate optimization of either LCC or GCV. In all examples this could be achieved with LCC without significant perturbation of the values in pixels where the regularization parameter was originally selected accurately. GCV could not be optimized for the renal data, and in the CT data only at the cost of image resolution. Using the implementations given, calculation times were sufficiently short for routine application in the clinic.

  11. GH receptor signaling in skeletal muscle and adipose tissue in human subjects following exposure to an intravenous GH bolus

    Jørgensen, Jens O L; Jessen, Niels; Pedersen, Steen Bønløkke;

    2006-01-01

    Growth hormone (GH) regulates muscle and fat metabolism, which impacts on body composition and insulin sensitivity, but the underlying GH signaling pathways have not been studied in vivo in humans. We investigated GH signaling in biopsies from muscle and abdominal fat obtained 30 (n = 3) or 60 (n...... = 3) min after an intravenous bolus of GH (0.5 mg) vs. saline in conjunction with serum sampling in six healthy males after an overnight fast. Expression of the following signal proteins were assayed by Western blotting: STAT5/p-STAT5, MAPK, and Akt/PKB. IRS-1-associated PI 3-kinase activity...... tended to increase after GH in muscle and fat, respectively. We conclude that 1) STAT5 is acutely activated in human muscle and fat after a GH bolus, but additional downstream GH signaling was significant only in fat; 2) the direct GH effects in muscle need further characterization; and 3) this human...

  12. Periodic versus intermittent adaptive cycles in quasispecies coevolution.

    Seeholzer, Alexander; Frey, Erwin; Obermayer, Benedikt

    2014-09-19

    We study an abstract model for the coevolution between mutating viruses and the adaptive immune system. In sequence space, these two populations are localized around transiently dominant strains. Delocalization or error thresholds exhibit a novel interdependence because immune response is conditional on the viral attack. An evolutionary chase is induced by stochastic fluctuations and can occur via periodic or intermittent cycles. Using simulations and stochastic analysis, we show how the transition between these two dynamic regimes depends on mutation rate, immune response, and population size. PMID:25279644

  13. Reduction of contrast medium volume in abdominal aorta CTA: Multiphasic injection technique versus a test bolus volume

    Nijhof, Wouter H., E-mail: w.h.nijhof@student.utwente.nl [University of Twente, MIRA-Institute for Biomedical Technology and Technical Medicine, P.O. Box 21, 7500 AE Enschede (Netherlands); Vos, Charlotte S. van der, E-mail: c.s.vandervos@student.utwente.nl [University of Twente, MIRA-Institute for Biomedical Technology and Technical Medicine, P.O. Box 21, 7500 AE Enschede (Netherlands); Anninga, Bauke, E-mail: b.anninga@student.utwente.nl [University of Twente, MIRA-Institute for Biomedical Technology and Technical Medicine, P.O. Box 21, 7500 AE Enschede (Netherlands); Jager, Gerrit J., E-mail: g.jager@JBZ.nl [Department of Radiology, Jeroen Bosch Hospital, Henri Dunantstraat 1, 5223 GZ ’s-Hertogenbosch (Netherlands); Rutten, Matthieu J.C.M., E-mail: mj.rutten@online.nl [Department of Radiology, Jeroen Bosch Hospital, Henri Dunantstraat 1, 5223 GZ ’s-Hertogenbosch (Netherlands)

    2013-09-15

    Objective: The purpose of this study is to reduce the administered contrast medium volume in abdominal CTA by using a test bolus injection, with the preservation of adequate quantitative and qualitative vessel enhancement. Study design: For this technical efficacy study 30 patients, who were referred for a CTA examination of the abdominal aorta, were included. Randomly 15 patients were assigned to undergo a multiphasic injection protocol and received 89 mL of contrast medium (Optiray 350) (protocol I). Fifteen patients were assigned to the test bolus injection protocol (protocol II), which implies injection of a 10 mL test bolus of Optiray 350 prior to performing CTA with a 40 mL of contrast medium. Quantitative assessment of vascular enhancement was performed by measuring the amount of Hounsfield Units in the aorta at 30 positions from the celiac trunk to the iliac arteries in both groups. Qualitative assessment was performed by three radiologists who scored the images at a 5-point scale. Results: Quantitative assessment showed that there was no significant difference in vascular enhancement for patients between the two protocols, with mean attenuation values of 280.9 ± 50.84 HU and 258.60 ± 39.28 HU, respectively. The image quality of protocol I was rated 4.31 (range: 3.67/5.00) and of protocol II 4.11 (range: 2.67/5.00). These differences were not statistically significant. Conclusion: This study showed that by using a test bolus injection and the administration of 50 mL of contrast medium overall, CTA of the abdominal aorta can reliably be performed, with regard to quantitative and qualitative adequate vessel enhancement.

  14. Transcatheter Thrombolysis with High-Dose Bolus Tissue Plasminogen Activator in Iatrogenic Arterial Occlusion after Femoral Arterial Catheterization

    Purpose: To assess the efficacy of percutaneous local thrombolysis with high-dose bolus recombinant tissue plasminogen activator (rt-PA) in patients with acute limb ischemia due to arterial thrombosis after cardiac catheterization.Methods: We treated eight patients (7 men; mean age 56 years) with thrombotic occlusion of both the common femoral artery (CFA) and external iliac artery (EIA) in six patients and of the CFA only in two patients. Two 5 mg boluses of rt-PA were injected into the proximal clot through a 5 Fr end-hole catheter and subsequently two additional boluses of 5 mg rt-PA were given through a catheter with multiple side-holes. In case of a significant amount of residual thrombus, a continuous infusion of 2.5 mg/hr of rt-PA was started.Results: Successful lysis was achieved in all patients. The mean duration of lysis was 2 hr 41 min. The mean total amount of rt-PA delivered was 23.16 mg. In four patients unmasked flow-limited dissections confined to the CFA were managed by prolonged balloon dilatation, while in the remaining four patients with extension of the dissection to the external iliac artery one or two Easy Wallstents were implanted. There was prompt relief of lower limb ischemic symptoms and signs in all patients. Two groin hematomas were conservatively treated.Clinical and color Doppler flow imaging follow-up with a mean duration of 15 months, showed no reappearance of ischemic symptoms or development of restenosis in any of the patients. One patient died 6 months after thrombolysis.Conclusions: Transcatheter thrombolysis with high-dose bolus rt-PA is a safe and effective treatment inpatients with iatrogenic arterial occlusion after femoral catheterization. Underlying dissections should be treated by prolonged balloon dilatation but stent implantation is often required

  15. Low-dose esmolol bolus reduces seizure duration during electroconvulsive therapy: a double-blind, placebo-controlled study

    Broek, Walter; Leentjens, A.F.; Kusuma, Ari; Bruijn, Jan; Mulder, Paul

    1999-01-01

    textabstractWe have measured the effect of a bolus dose of esmolol 80 mg i.v. on heart rate, and systolic (SAP), diastolic (DAP) and mean (MAP) arterial pressures during electroconvulsive therapy (ECT). We also assessed seizure duration using both the cuff method and two-lead EEG. We studied 20 patients in a double-blind, placebo-controlled, within-patient blocked randomized study. No patient was receiving psychotherapeutic drugs or had cardiovascular disease. Esmolol significantly reduced he...

  16. Bolus ingestion of individual branched-chain amino acids alters plasma amino acid profiles in young healthy men

    Matsumoto, Takuya; Nakamura, Koichi; Matsumoto, Hideki; Sakai, Ryosei; Kuwahara, Tomomi; Kadota, Yoshihiro; Kitaura, Yasuyuki; SATO, JUICHI; Shimomura, Yoshiharu

    2014-01-01

    Physiological conditions in humans affect plasma amino acid profiles that might have potential for medical use. Because the branched-chain amino acids (BCAAs) leucine, isoleucine and valine are used as medicines and supplements, we investigated the acute effects of individual BCAAs (10–90 mg/kg body weight) or mixed BCAAs ingested as a bolus on plasma amino acid profiles in young healthy men. Plasma leucine levels rapidly increased and peaked around 30 min after leucine ingestion. Concentrati...

  17. Cross comparison and modelling of Goldman Sachs, Morgan Stanley, JPMorgan Chase, Bank of America, and Franklin Resources

    Kitov, Ivan

    2012-01-01

    We have studied statistical characteristics of five share price time series. For each stock price, we estimated a best fit quantitative model for the monthly closing price as based on the decomposition into two defining consumer price indices selected from a large set of CPIs. It was found that there are two pairs of similar models (Bank of America/Morgan Stanley and Goldman Sachs/JPMorgan Chase) with a standalone model for Franklin Resources. From each pair, one can choose the company with t...

  18. Cardiac output obtained from test bolus injections as a factor in contrast injection rate revision of following coronary CT angiography

    Konno, Masahiko [Division of Diagnostic Image Analysis, Graduate School of Medicine, Tohoku University, Miyagi (Japan); Yamagata Prefecture Comprehensive Rehabilitation and Education Center, Yamagata (Japan)], E-mail: mkonno@med.tohoku.ac.jp; Hosokai, Yoshiyuki; Usui, Akihito; Abe, Mitsuya; Tateishi, Toshiki; Kawasumi, Yusuke; Saito, Haruo [Division of Diagnostic Image Analysis, Graduate School of Medicine, Tohoku University, Miyagi (Japan); Tsuda, Masashi; Ota, Hideki; Takase, Kei [Division of Diagnostic Radiology, Graduate School of Medicine, Tohoku University, Miyagi (Japan)

    2012-12-15

    Background.. Optimal contrast enhancement is crucial for the detection of coronary artery stenoses and atherosclerotic changes in coronary CT angiography (CTA). Purpose To demonstrate the feasibility of using the cardiac output (CO) obtained from the test bolus injection data-set (CO test) as a factor in contrast injection rate revision of the following coronary CTA. Material and Methods. The test bolus injection data-sets of 52 consecutive coronary CTAs were examined. CO test was calculated from the test bolus data-set. Aortic peak enhancement (APE) was measured on the following coronary CTA. We simulated the APE at a fixed contrast injection rate of 4 mL/s (simAPE) in each patient. Results. The ranges of COtest and simAPE were 2.82-7.56 L/min and 194-527 Hounsfield Units, respectively. There was a significant negative correlation (R = -0.802, P < 0.001) between simAPE and COtest. Conclusion. COtest can be used for injection rate revision on coronary CTA.

  19. Locoregional Outcomes of Inflammatory Breast Cancer Patients Treated With Standard Fractionation Radiation and Daily Skin Bolus in the Taxane Era

    Purpose: To assess locoregional outcomes of inflammatory breast cancer (IBC) patients who received standard fractionation radiation with daily skin bolus and taxanes as part of combined-modality therapy (CMT). Methods and Materials: We retrospectively reviewed the charts of 107 patients diagnosed with IBC between January 1995 and March 2006 who presented to our department for adjuvant radiation therapy (RT). Results: All patients received chemotherapy (95% anthracycline and 95% taxane), modified radical mastectomy, and RT to the chest wall and regional lymphatics using standard fractionation to 50 Gy and daily skin bolus. The RT to the chest wall was delivered via electrons (55%) or photons (45%) in daily fractions of 180 cGy (73%) or 200 cGy (27%). Scar boost was performed in 11%. A majority (84%) of patients completed the prescribed treatment. Median follow-up was 47 months (range, 10-134 months). Locoregional control (LRC) at 3 years and 5 years was 90% and 87%, respectively. Distant metastases-free survival (DMFS) at 3 years and 5 years was 61% and 47%, respectively. Conclusions: Excellent locoregional control was observed in this population of IBC patients who received standard fractionation radiation with daily skin bolus and taxanes as part of combined-modality therapy. Distant metastases-free survival remains a significant therapeutic challenge.

  20. Proteomic Analysis of Protein Turnover by Metabolic Whole Rodent Pulse-Chase Isotopic Labeling and Shotgun Mass Spectrometry Analysis.

    Savas, Jeffrey N; Park, Sung Kyu; Yates, John R

    2016-01-01

    The analysis of protein half-life and degradation dynamics has proven critically important to our understanding of a broad and diverse set of biological conditions ranging from cancer to neurodegeneration. Historically these protein turnover measures have been performed in cells by monitoring protein levels after "pulse" labeling of newly synthesized proteins and subsequent chase periods. Comparing the level of labeled protein remaining as a function of time to the initial level reveals the protein's half-life. In this method we provide a detailed description of the workflow required for the determination of protein turnover rates on a whole proteome scale in vivo.Our approach starts with the metabolic labeling of whole rodents by restricting all the nitrogen in their diet to exclusively nitrogen-15 in the form of spirulina algae. After near complete organismal labeling with nitrogen-15, the rodents are then switched to a normal nitrogen-14 rich diet for time periods of days to years. Tissues are harvested, the extracts are fractionated, and the proteins are digested to peptides. Peptides are separated by multidimensional liquid chromatography and analyzed by high resolution orbitrap mass spectrometry (MS). The nitrogen-15 containing proteins are then identified and measured by the bioinformatic proteome analysis tools Sequest, DTASelect2, and Census. In this way, our metabolic pulse-chase approach reveals in vivo protein decay rates proteome-wide. PMID:26867752

  1. Decoding Biosynthetic Pathways in Plants by Pulse-Chase Strategies Using 13CO2 as a Universal Tracer

    Adelbert Bacher

    2016-07-01

    Full Text Available 13CO2 pulse-chase experiments monitored by high-resolution NMR spectroscopy and mass spectrometry can provide 13C-isotopologue compositions in biosynthetic products. Experiments with a variety of plant species have documented that the isotopologue profiles generated with 13CO2 pulse-chase labeling are directly comparable to those that can be generated by the application of [U-13C6]glucose to aseptically growing plants. However, the application of the 13CO2 labeling technology is not subject to the experimental limitations that one has to take into account for experiments with [U-13C6]glucose and can be applied to plants growing under physiological conditions, even in the field. In practical terms, the results of biosynthetic studies with 13CO2 consist of the detection of pairs, triples and occasionally quadruples of 13C atoms that have been jointly contributed to the target metabolite, at an abundance that is well above the stochastic occurrence of such multiples. Notably, the connectivities of jointly transferred 13C multiples can have undergone modification by skeletal rearrangements that can be diagnosed from the isotopologue data. As shown by the examples presented in this review article, the approach turns out to be powerful in decoding the carbon topology of even complex biosynthetic pathways.

  2. Automated bolus advisor control and usability study (ABACUS: does use of an insulin bolus advisor improve glycaemic control in patients failing multiple daily insulin injection (MDI therapy? [NCT01460446

    Cavan David A

    2012-10-01

    Full Text Available Abstract Background People with T1DM and insulin-treated T2DM often do not follow and/or adjust their insulin regimens as needed. Key contributors to treatment non-adherence are fear of hypoglycaemia, difficulty and lack of self-efficacy associated with insulin dose determination. Because manual calculation of insulin boluses is both complex and time consuming, people may rely on empirical estimates, which can result in persistent hypoglycaemia and/or hyperglycaemia. Use of automated bolus advisors (BA has been shown to help insulin pump users to more accurately meet prandial insulin dosage requirements, improve postprandial glycaemic excursions, and achieve optimal glycaemic control with an increased time within optimal range. Use of a BA containing an early algorithm based on sliding scales for insulin dosing has also been shown to improve HbA1c levels in people treated with multiple daily insulin injections (MDI. We designed a study to determine if use of an automated BA can improve clinical and psychosocial outcomes in people treated with MDI. Methods/design The Automated Bolus Advisor Control and Usability Study (ABACUS is a 6-month, prospective, randomised, multi-centre, multi-national trial to determine if automated BA use improves glycaemic control as measured by a change in HbA1c in people using MDI with elevated HbA1c levels (#62;7.5%. A total of 226 T1DM and T2DM participants will be recruited. Anticipated attrition of 20% will yield a sample size of 90 participants, which will provide #62;80% power to detect a mean difference of 0.5%, with SD of 0.9%, using a one-sided 5% t-test, with 5% significance level. Other measures of glycaemic control, self-care behaviours and psychosocial issues will also be assessed. Discussion It is critical that healthcare providers utilise available technologies that both facilitate effective glucose management and address concerns about safety and lifestyle. Automated BAs may help people using MDI to

  3. A randomized phase III multicenter trial comparing irinotecan in combination with the Nordic bolus 5-FU and folinic acid schedule or the bolus/infused de Gramont schedule (Lv5FU2) in patients with metastatic colorectal cancer

    Glimelius, B; Sørbye, H; Balteskard, L;

    2008-01-01

    resection rate did not differ (4% versus 6%, P = 0.3). Grade 3/4 neutropenia (11% versus 5%, P = 0.01) and grade 2 alopecia (18% versus 9%, P = 0.002) were more common in the FLIRI group. The 60-day mortality was 2.4% versus 2.1%. CONCLUSIONS: Irinotecan with the bolus Nordic schedule (FLIRI) is a...... convenient treatment with PFS and OS comparable to irinotecan with the Lv5FU2 schedule. Neutropenia and alopecia are more prevalent, but both regimens are equally well tolerated....

  4. Low contrast volume run-off CT angiography with optimized scan time based on double-level test bolus technique – feasibility study

    Purpose: To verify the technical feasibility of low contrast volume (40 mL) run-off CT angiography (run-off CTA) with the individual scan time optimization based on double-level test bolus technique. Materials and methods: A prospective study of 92 consecutive patients who underwent run-off CTA performed with 40 mL of contrast medium (injection rate of 6 mL/s) and optimized scan times on a second generation of dual-source CT. Individual optimized scan times were calculated from aortopopliteal transit times obtained on the basis of double-level test bolus technique – the single injection of 10 mL test bolus and dynamic acquisitions in two levels (abdominal aorta and popliteal arteries). Intraluminal attenuation (HU) was measured in 6 levels (aorta, iliac, femoral and popliteal arteries, middle and distal lower-legs) and subjective quality (3-point score) was assessed. Relations of image quality, test bolus parameters and arterial circulation involvement were analyzed. Results: High mean attenuation (HU) values (468; 437; 442; 440; 342; 274) and quality score in all monitored levels was achieved. In 91 patients (0.99) the sufficient diagnostic quality (score 1–2) in aorta, iliac and femoral arteries was determined. A total of 6 patients (0.07) were not evaluable in distal lower-legs. Only the weak indirect correlation of image quality and test-bolus parameters was proved in iliac, femoral and popliteal levels (r values: −0.263, −0.298 and −0.254). The statistically significant difference of the test-bolus parameters and image quality was proved in patients with occlusive and aneurysmal disease. Conclusion: We proved the technical feasibility and sufficient quality of run-off CTA with low volume of contrast medium and optimized scan time according to aortopopliteal transit time calculated from double-level test bolus

  5. Low contrast volume run-off CT angiography with optimized scan time based on double-level test bolus technique – feasibility study

    Baxa, Jan, E-mail: baxaj@fnplzen.cz [Department of Imaging Methods, University Hospital and Charles University Medical School in Pilsen (Czech Republic); Vendiš, Tomáš [Department of Imaging Methods, University Hospital and Charles University Medical School in Pilsen (Czech Republic); Moláček, Jiří [Department of Surgery, University Hospital and Charles University Medical School in Pilsen (Czech Republic); Štěpánková, Lucie [Department of Internal Medicine, University Hospital and Charles University Medical School in Pilsen (Czech Republic); Flohr, Thomas; Schmidt, Bernhard; Korporaal, Johannes G. [Siemens Healthcare, Computed Tomography Division, Forchheim (Germany); Ferda, Jiří [Department of Imaging Methods, University Hospital and Charles University Medical School in Pilsen (Czech Republic)

    2014-03-15

    Purpose: To verify the technical feasibility of low contrast volume (40 mL) run-off CT angiography (run-off CTA) with the individual scan time optimization based on double-level test bolus technique. Materials and methods: A prospective study of 92 consecutive patients who underwent run-off CTA performed with 40 mL of contrast medium (injection rate of 6 mL/s) and optimized scan times on a second generation of dual-source CT. Individual optimized scan times were calculated from aortopopliteal transit times obtained on the basis of double-level test bolus technique – the single injection of 10 mL test bolus and dynamic acquisitions in two levels (abdominal aorta and popliteal arteries). Intraluminal attenuation (HU) was measured in 6 levels (aorta, iliac, femoral and popliteal arteries, middle and distal lower-legs) and subjective quality (3-point score) was assessed. Relations of image quality, test bolus parameters and arterial circulation involvement were analyzed. Results: High mean attenuation (HU) values (468; 437; 442; 440; 342; 274) and quality score in all monitored levels was achieved. In 91 patients (0.99) the sufficient diagnostic quality (score 1–2) in aorta, iliac and femoral arteries was determined. A total of 6 patients (0.07) were not evaluable in distal lower-legs. Only the weak indirect correlation of image quality and test-bolus parameters was proved in iliac, femoral and popliteal levels (r values: −0.263, −0.298 and −0.254). The statistically significant difference of the test-bolus parameters and image quality was proved in patients with occlusive and aneurysmal disease. Conclusion: We proved the technical feasibility and sufficient quality of run-off CTA with low volume of contrast medium and optimized scan time according to aortopopliteal transit time calculated from double-level test bolus.

  6. Contrast agent bolus tracking with a fixed threshold or a manual fast start for coronary CT angiography

    Comparison of bolus tracking with a fixed threshold versus a manual fast start for coronary CT angiography. We retrospectively analysed 320-row coronary CT angiography of 50 patients with suspected or known coronary artery disease. Twenty-five examinations were initiated by a bolus tracking method (group 1), 25 examinations with a manual fast surestart (group 2). Mean attenuation values in the ascending aorta were 519 ± 111 Hounsfield units (HU) in group 1 and 476 ± 65 HU in group 2 (p = 0.10). Assessable vessel lengths were 171 ± 44 mm vs 172 ± 29 mm for the right coronary artery (p = 0.91), 11 ± 4 mm vs 12 ± 4 mm for the left main (p = 0.9), 163 ± 28 mm vs 151 ± 26 mm for the left anterior descending coronary artery (p = 0.11) and 125 ± 41 mm vs 110 ± 37 mm for the left circumflex coronary artery (p = 0.18). Image quality for all coronary arteries was not significantly different between the groups (p > 0.41). The attenuation ratio between the left and right ventricle was 2.8 ± 0.7 vs 3.6 ± 1.0 (p = 0.003). Significantly less contrast agent was used in group 2 (64 ± 6 ml vs 80 ± 0 ml; p < 0.001). Bolus tracking with a fixed threshold and with a manual fast start are both suitable methods; the fast start allowed a reduction of contrast agent volumes. (orig.)

  7. Evaluation of rapid sequence CT scan with intravenous bolus injection of contrast medium on the diagnosis of pancreatic disease

    Hase, Mamoru; Sako, Masao; Watanabe, Hideaki; Shimizu, Tadafumi; Okuda, Kenichiro; Kono, Michio; Sakamoto, Kazuo; Yonezawa, Kazuyuki.

    1988-08-01

    Rapid sequential CT scans with 6 to 10 multislices were performed after intravenous bolus injection of contrast media on 46 patients with suspected pancreatic diseases. The procedure remarkably improved the ability to visualize the whole pancreatic parenchym as well as adjacent vascular structures, to result from not to permit scan-skipping due to respiratory movement. The main pancreatic duct was well delineated against the back ground of highly enhanced pancreatic parenchym. In case of pancreatic carcinoma, the tumors were well defined as low density area. Invasion to peripancreatic vessels, even to gastroduodenal artery were detectable. The procedure may become an essential diagnostic method for detecting small lesions of the pancreas.

  8. Adaptive Lighting

    Petersen, Kjell Yngve; Søndergaard, Karin; Kongshaug, Jesper

    2015-01-01

    Adaptive LightingAdaptive lighting is based on a partial automation of the possibilities to adjust the colour tone and brightness levels of light in order to adapt to people’s needs and desires. IT support is key to the technical developments that afford adaptive control systems. The possibilities offered by adaptive lighting control are created by the ways that the system components, the network and data flow can be coordinated through software so that the dynamic variations are controlled i...

  9. The Coevolution of "Tyrannosaurus" & Its Prey: Could "Tyrannosaurus" Chase down & Kill a "Triceratops" for Lunch?

    May, S. Randolph

    2014-01-01

    Students will analyze the coevolution of the predator-prey relationships between "Tyrannosaurus rex" and its prey species using analyses of animal speeds from fossilized trackways, prey-animal armaments, adaptive behaviors, bite marks on prey-animal fossils, predator-prey ratios, and scavenger competition. The students will be asked to…

  10. Evaluation of diesel fleet emissions and control policies from plume chasing measurements of on-road vehicles

    Lau, Chui Fong; Rakowska, Agata; Townsend, Thomas; Brimblecombe, Peter; Chan, Tat Leung; Yam, Yat Shing; Močnik, Griša; Ning, Zhi

    2015-12-01

    Vehicle emissions are an important source of urban air pollution. Diesel fuelled vehicles, although constituting a relatively small fraction of fleet population in many cities, are significant contributors to the emission inventory due to their often long mileage for goods and public transport. Recent classification of diesel exhaust as carcinogenic by the World Health Organization also raises attention to more stringent control of diesel emissions to protect public health. Although various mandatory and voluntary based emission control measures have been implemented in Hong Kong, there have been few investigations to evaluate if the fleet emission characteristics have met desired emission reduction objectives and if adoption of an Inspection/Maintenance (I/M) programme has been effective in achieving these objectives. The limitations are partially due to the lack of cost-effective approaches for the large scale characterisation of fleet based emissions to assess the effectiveness of control measures and policy. This study has used a plume chasing method to collect a large amount of on-road vehicle emission data of Hong Kong highways and a detailed analysis was carried out to provide a quantitative evaluation of the emission characteristics in terms of the role of high and super-emitters in total emission reduction, impact of after-treatment on the multi-pollutants reduction strategy and the trend of NO2 emissions with newer emission standards. The study revealed that not all the high-emitters are from those vehicles of older Euro emission standards. Meanwhile, there is clear evidence that high-emitters for one pollutant may not be a high-emitter for another pollutant. Multi-pollutant control strategy needs to be considered in the enactment of the emission control policy which requires more comprehensive retrofitting technological solutions and matching I/M programme to ensure the proper maintenance of fleets. The plume chasing approach used in this study also

  11. Comparison of dose distribution by means of bolus versus water bath phantom technique in treatment of cutaneous sarcoma of an extremity

    Research showed that cutaneous involvement by Kaposi sarcoma is frequently diffuse, requiring large-field irradiation. The authors have compared selective tissue compensation accomplished with a 1.5-cm bolus cast with that achieved by the 2-cm water bath phantom technique. Dosimetric determinations were performed by using 6MVX and cobalt-60 with heterogeneity corrections. Application of a 1.5-cm bolus effectively eliminated dose buildup and provided tissue compensation equivalent or superior to that of water bath phantom technique. Treatment of other cutaneous lesions (such as angiosarcoma) that require higher total doses should be accompanied by dosimetric evaluation, because a ±5% range in delivered dose may result in a significant total dose differential over the target volume (300-700 cGy) in either technique. Application of 1.5-cm bolus provided superior accuracy in treatment positioning and dose homogeneity comparable to the more standard water bath phantom technique

  12. Effects of Bolus and Continuous Nasogastric Feeding on Gastric Emptying, Small Bowel Water Content, Superior Mesenteric Artery Blood Flow, and Plasma Hormone Concentrations in Healthy Adults

    Chowdhury, Abeed H.; Murray, Kathryn; Hoad, Caroline L.; Costigan, Carolyn; Marciani, Luca; Macdonald, Ian A.; Bowling, Timothy E.; Lobo, Dileep N.

    2016-01-01

    Objective: We aimed to demonstrate the effect of continuous or bolus nasogastric feeding on gastric emptying, small bowel water content, and splanchnic blood flow measured by magnetic resonance imaging (MRI) in the context of changes in plasma gastrointestinal hormone secretion. Background: Nasogastric/nasoenteral tube feeding is often complicated by diarrhea but the contribution of feeding strategy to the etiology is unclear. Methods: Twelve healthy adult male participants who underwent nasogastric intubation before a baseline MRI scan, received 400 mL of Resource Energy (Nestle) as a bolus over 5 minutes or continuously over 4 hours via pump in this randomized crossover study. Changes in gastric volume, small bowel water content, and superior mesenteric artery blood flow and velocity were measured over 4 hours using MRI and blood glucose and plasma concentrations of insulin, peptide YY, and ghrelin were assayed every 30 minutes. Results: Bolus nasogastric feeding led to significant elevations in gastric volume (P < 0.0001), superior mesenteric artery blood flow (P < 0.0001), and velocity (P = 0.0011) compared with continuous feeding. Both types of feeding reduced small bowel water content, although there was an increase in small bowel water content with bolus feeding after 90 minutes (P < 0.0068). Similarly, both types of feeding led to a fall in plasma ghrelin concentration although this fall was greater with bolus feeding (P < 0.0001). Bolus feeding also led to an increase in concentrations of insulin (P = 0.0024) and peptide YY (P < 0.0001), not seen with continuous feeding. Conclusion: Continuous nasogastric feeding does not increase small bowel water content, thus fluid flux within the small bowel is not a major contributor to the etiology of tube feeding-related diarrhea. PMID:25549202

  13. Adaptive skills

    Staša Stropnik; Jana Kodrič

    2013-01-01

    Adaptive skills are defined as a collection of conceptual, social and practical skills that are learned by people in order to function in their everyday lives. They include an individual's ability to adapt to and manage her or his surroundings to effectively function and meet social or community expectations. Good adaptive skills promote individual's independence in different environments, whereas poorly developed adaptive skills are connected to individual's dependency and with g...

  14. Arrowwood National Wildlife Refuge, Chase Lake National Wildlife Refuge, Half-Way Lake Easement Refuge, Hobart Lake Easement Refuge, Stoney Slough Easement Refuge, Tomahawk Easement Refuge : Narrative report : Calendar year - 1969

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Arrowwood NWR (including Chase Lake NWR and the easement refuges) outlines Refuge accomplishments during the 1969 calendar year....

  15. Arrowwood National Wildlife Refuge, Chase Lake National Wildlife Refuge, Half-Way Lake Easement Refuge, Hobart Lake Easement Refuge, Stoney Slough Easement Refuge, Tomahawk Easement Refuge : Narrative report : Calendar year - 1970

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Arrowwood NWR (including Chase Lake NWR and the easement refuges) outlines Refuge accomplishments during the 1970 calendar year....

  16. Arrowwood National Wildlife Refuge, Chase Lake National Wildlife Refuge, Half-Way Lake Easement Refuge, Hobart Lake Easement Refuge, Stoney Slough Easement Refuge, Tomahawk Easement Refuge : Narrative report : Calendar year - 1968

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Arrowwood NWR (including Chase Lake NWR and the easement refuges) outlines Refuge accomplishments during the 1968 calendar year....

  17. Oceanographic station data from bottle casts from the CHASE from Ocean Weather Station B (OWS-B) in the North Atlantic Ocean from 27 December 1973 to 07 January 1974 (NODC Accession 7400475)

    National Oceanic and Atmospheric Administration, Department of Commerce — Oceanographic station data were collected from the CHASE within a 1-mile radius of Ocean Weather Station B (5630N 5100W) and in transit. Data were collected by the...

  18. Oceanographic station data from bottle casts from the CHASE from Ocean Weather Station D (OWS-D) in the North Atlantic Ocean 08 February 1971 to 02 March 1971 (NODC Accession 7101184)

    National Oceanic and Atmospheric Administration, Department of Commerce — Oceanographic station data were collected from the CHASE within a 1-mile radius of Ocean Weather Station D (4400N 04100W) and in transit. Data were collected by the...

  19. Oceanographic station data from CTD casts from the CHASE AND ESCANABA from Ocean Weather Station D (OWS-D) and E (OWS-E) in the North Atlantic Ocean 11 April 1969 to 12 May 1969 (NODC Accession 6900885)

    National Oceanic and Atmospheric Administration, Department of Commerce — Oceanographic station data were collected from the CHASE and ESCANABA within a 1-mile radius of Ocean Weather Station D (4400N 04100W), E (3500N 04800W), and in...

  20. Oceanographic station data from CTD and bottle casts from the CHASE from Ocean Weather Station D (OWS-D) in the North Atlantic Ocean from 24 March 1972 to 18 April 1972 (NODC Accession 7300020)

    National Oceanic and Atmospheric Administration, Department of Commerce — Oceanographic station data were collected from the CHASE within a 1-mile radius of Ocean Weather Station D (4400N 4100W) and in transit. Data were collected by the...

  1. Identificação de Paspalum notatum fluegge e Axonopus affinis chase através da análise de fragmentos foliares Identification of Paspalum notatum fluegge and Axonopus affinis chase through leaf fragments analysis

    Maria Cláudia Lopes Nogueira

    1999-03-01

    Full Text Available Este trabalho teve como objetivo a caracterização e identificação de fragmentos foliares de Paspalum notatum Fluegge e Axonopus affinis Chase, como forma de subsidiar projetos de avaliação da dieta de animais fistulados. Para a caracterização das espécies, foram feitas várias coletas de folhas em áreas de pastagem natural do Campus da Universidade Federal de Santa Maria (RS, de maio de 1992 a junho de 1993. A diferenciação das espécies foi baseada no padrão de nervação, presença de pêlos e características do ápice e bordo foliar, observadas com auxílio de estereomicroscópio. A habilidade de um observador em identificar fragmentos das duas espécies numa mistura e a eficácia dos descritores foliares mencionados foram testadas através de análise estatística. Desta forma, foi constatado que o padrão de nervação é o melhor critério de diferenciação e que A. affinis difere de P. notatum, basicamente, pelo ápice foliar obtuso e pela presença de nervuras quaternárias. A análise estatística confirmou a capacidade do observador em reconhecer fragmentos das duas espécies.This research aimed at the characterization and identification of leaves, fragments of Paspalum notatum Fluegge and Axonopus affinis Chase, for future studies of diet evaluation of fistuleted animals. For the species characterization, several collections of leaves were made in native pasture areas at the UFSM Campus (Santa Maria, RS from May, 1992 to June, 1993. The differentiation of the species was based on the leave’s venation pattern, hair presence, leaf border and apex features, observed with a stereomicroscope. The obverver’s ability to identify the two species of leaves in a misture were tested with statistical analysis. It was observed that the venation pattern is the best characterization criteria and that A. affinis differs from P. notatum mainly by the obtuse leaf apex and by the quaternary vein presence. The statistical analysis

  2. The usefulness of test bolus examination in three-dimensional contrast-enhanced MR angiography of the carotid artery

    To compare the usefulness of test bolus examination in three-dimensional contrast enhanced MR angiography of the carotid artery with that of the fixed delay time method. Sixty consecutive patients (mean age, 60.1 years) in whom carotid arterial disease was suspected and who were examined during a 17-month period were divided into two equal groups. For group A, a fixed delay time of 5 secs was used, while for group B, the delay time of the test bolus examination was calculated from the signal intensity versus time curve of the carotid artery, obtained after the test injection of 1ml contrast material into the right brachial vein. Overall image quality, discrimination between the arterial and the venous phase, and the contrast-to-noise ratio(CNR) of the carotid artery were compared between the two groups. Overall image quality was classified as excellent, good, moderate or poor, and discrimination between the two phases was graded IV-I according to the degree of jugular venous enhancement. In group A, overall image quality of the carotid artery was classified as excellent or good in 13 (43.3%) and 9 (30.0%) cases, respectively, while in group B the corresponding figures were 23 (76.7%) and 5 (16.7%). The differences between the two groups were statistically significant (ρ <0.05). In terms of discrimination between the arterial and venous phase, 20 (66.7%) of the 30 cases in group A were assigned grade IV or III, while 28 (93.3%) of the 30 in group B were assigned these same grades (ρ <0.05). The CNR of the carotid artery was higher in group B(67.1±16.1) than in group A(27.3±17.8), with statistical significance(ρ <0.05). For examination of the carotid artery, contrast enhanced MR angiography using a test bolus is superior to the fixed delay time method

  3. Adaptive Lighting

    Petersen, Kjell Yngve; Søndergaard, Karin; Kongshaug, Jesper

    2015-01-01

    Adaptive Lighting Adaptive lighting is based on a partial automation of the possibilities to adjust the colour tone and brightness levels of light in order to adapt to people’s needs and desires. IT support is key to the technical developments that afford adaptive control systems. The possibilities...... offered by adaptive lighting control are created by the ways that the system components, the network and data flow can be coordinated through software so that the dynamic variations are controlled in ways that meaningfully adapt according to people’s situations and design intentions. This book discusses...... distributed differently into an architectural body. We also examine what might occur when light is dynamic and able to change colour, intensity and direction, and when it is adaptive and can be brought into interaction with its surroundings. In short, what happens to an architectural space when artificial...

  4. Designing and living in a new industrial suburb: experiences in the Cannock Chase coalfield from the 1950s to the 1970s

    Gareth Evans; Peter J Larkham

    2004-01-01

    The immediate postwar period was one of major change in UK industry and society. The restructuring of the coal industry involved large-scale population movement from declining areas to more productive areas including Cannock Chase. New housing estates were constructed to house these migrants. In this paper we review aspects of the location and design of these estates, and discuss a long-term study of the experiences of miners and their families in a new physical and cultural context. The long...

  5. 虚拟人追逐行为的一种决策模型%Decision-making Model of Virtual Human's Chasing Behavior

    卞玉龙; 刘箴

    2012-01-01

    Behavior simulation is an important issue in the field of virtual reality, chasing is a common behavior of animal and human, and modeling chasing behavior is an interesting topic. A chasing behavior between chaser and escaper was analyzed, the parameters of human physiology and emotion were introduced, and the formulas among emotion, energy and velocity were set up. The behavior decision model was proposed based on non-cooperative dynamic game. A simulation test on a computer was designed. The result shows that the method can well simulate some physiological features and psychological characteristics of human’s chasing behavior.%行为仿真是虚拟现实领域中的一个重要课题,追逐是动物和人类最常见的行为,建立追逐行为模型是一个有趣的话题。分析了一种包含追逐者和逃跑者的追逐行为,引入人的生理参数和情绪参数,建立了情绪、体力和速度之间的计算公式。根据非合作动态博弈原理建立了行为决策模型,我们在计算上进行了仿真实验,结果表明,我们的模型能较好模拟生命体追逐行为的一些生理特征和心理特性。

  6. Acute Effect of Whole-Body Periodic Acceleration on Brachial Flow-Mediated Vasodilatation Assessed by a Novel Semi-Automatic Vessel Chasing UNEXEF18G System

    Takase, Bonpei; Hattori, Hidemi; Tanaka, Yoshihiro; Uehata, Akimi; Nagata, Masayoshi; Ishihara, Masayuki; Fujita, Masatoshi

    2013-01-01

    Background Repeated application of whole-body periodic acceleration (WBPA) upregulates endothelial nitric oxide synthase and improves brachial artery endothelial function (BAEF) as assessed by measurement of flow-mediated vasodilatation (FMD). However, the acute effect of a single application of WBPA on BAEF has not been fully characterized. In addition, although a novel semi-automatic vessel chasing system (UNEXEF18G) has now been developed in Japan, the direct comparison of UNEXEF18G with a...

  7. A two-year revision: cross comparison and modeling of Goldman Sachs, Morgan Stanley, JPMorgan Chase, Bank of America, and Franklin Resources

    Kitov, Ivan

    2014-01-01

    Approximately two years ago we presented results of price modeling and extensive statistical analysis for share prices of five banks: Bank of America (BAC), Franklin Resources (BEN), Goldman Sachs (GS), JPMorgan Chase (JPM), and Morgan Stanley (MS). Using monthly closing prices (adjusted for splits and dividends) as a proxy to stock prices, we estimated the best fit (LSQ) quantitative price models based on the decomposition into two defining consumer price indices selected from a large set of...

  8. Capillary permeability of 99mTc-DTPA in canine myocardium determined by intracoronary bolus injection and residue detection

    Svendsen, Jesper Hastrup; Efsen, F; Haunsø, S

    1989-01-01

    chest dogs (group A) these indicators were administered separately as bolus injections into a cannulated diagonal branch of the left anterior descending coronary artery (LAD) and the curve of the response function was recorded by external activity registration. In further experiments on closed and open...... chest dogs (group B) 99mTc-DTPA was injected via a coronary angiography catheter into the ostium of the left coronary artery and the response curve was obtained by external registration. Regional myocardial perfusion coefficients were determined by the local 133xenon washout technique and from kinetic...... analysis of SIRD experiments. Plasma perfusion coefficients calculated by kinetic analysis of response curves from 99mTc-DTPA SIRD experiments (group A) were on average 98 v 102 ml.min-1.100 g-1 in 51Cr-EDTA experiments, in good agreement with the average plasma flow rate of 92 ml.min-1.100 g-1 determined...

  9. Model of the Glucose-Insulin-Glucagon Dynamics after Subcutaneous Administration of a Glucagon Rescue Bolus in Healthy Humans

    Wendt, Sabrina Lyngbye; Møller, Jan Kloppenborg; Haidar, Ahmad;

    In healthy individuals, insulin and glucagon work in a complex fashion to maintain blood glucose levels within a narrow range. This regulation is distorted in patients with diabetes. The hepatic glucose response due to an elevated glucagon level depends on the current insulin concentration and thus...... endogenous glucose production (EGP) can not be modelled without knowledge of the concentration of both hormones in plasma. Furthermore, literature suggests an upper limit to EGP irrespective of glucagon levels. We build a simulation model of the glucose-insulin-glucagon dynamics in man including saturation...... effect of EGP. Ten healthy subjects received a 1 mg subcutaneous (SC) glucagon bolus (GlucaGen®). Plasma samples were collected until 300 minutes post dose and analyzed for glucagon, insulin, and glucose concentrations. All observations were used to fit a physiological model of the glucose...

  10. Comparação do tempo de recuperação do mivacúrio em bolus e em infusão contínua Comparación del tiempo de recuperación del mivacúrio en bolus y en infusión continuada Comparison of recovery time of bolus and continuous infusion mivacurium

    Maria Cristina Simões de Almeida

    2005-02-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: O mivacúrio é um bloqueador neuromuscular (BNM de ação curta, que apresenta uma duração total não ultrapassando 24 minutos. As primeiras comunicações científicas relataram não haver diferenças significativas no tempo de recuperação, independentemente da forma de administração. No entanto, a experiência clínica aponta para recuperações mais prolongadas quando se administra o fármaco em infusão contínua. Este trabalho tem por objetivo comparar o tempo de recuperação do mivacúrio quando administrado em bolus e em forma contínua, em um grupo de pacientes jovens e adultos. MÉTODO: Foram analisados 40 pacientes jovens sem doenças neuromusculares. Após receberem midazolam como medicação pré-anestésica, foram monitorizados na sala de operação com ECG na derivação D II e realizada a aferição da pressão arterial indireta por método automático. Todos receberam propofol e fentanil, e a anestesia foi mantida com isoflurano, óxido nitroso e oxigênio. Após a indução, foram instalados o monitor da transmissão neuromuscular por acelerometria e, após a intubação, o capnógrafo e o analisador de gases. Foram divididos em 2 grupos iguais de acordo com o regime de administração de mivacúrio: os do grupo 1 receberam somente dose inicial em bolus e os do grupo 2, após a dose inicial e terem recuperado 10% de T1, receberam infusão contínua para manter uma T1 nesse valor. Foram anotados em ambos os grupos os valores de T1 e T4/T1 na fase de recuperação, a partir de T1 em 10% da resposta inicial, de minuto a minuto, até 30 minutos. RESULTADOS: Os grupos foram homogêneos em relação às variáveis antropométricas. O grupo 2 apresentou tempo de recuperação mais lenta do que os pacientes que receberam somente a dose inicial em bolus. Houve grande variação de doses de infusão entre pacientes e no próprio paciente no decorrer da infusão. CONCLUSÕES: Em pacientes jovens e adultos

  11. Experimental and clinical studies on CT diagnosis of pancreas cancer by intra-venous bolus injection of contrast medium

    CT scan with intravennus bolus injection of contrast medium (CT-Angio) was studied to improve the diagnostic ability for pancreatic carcinoma. CT scan planning of this procedure was estimated by intravenous bolus injection of sup(99m)Tc pertechnetate, the time-activity curve of which obtained corresponding to the pancreas indicated, that the optimal scan timing was 20 seconds after the beginning of the injection. Subsequently, CT-Angio was performed in 24 patients with proved pancreatic carcinoma, with an injection of 50 - 60 ml of 65% Angiografin at a rate of 5ml/sec. And the diagnostic accuracy of this procedure was evaluated comparing to that of plain-CT, conventional enhancement CT(CE-CT), and angiography. The difference of attenuation value between tumor and pancreas parenchyma was measured using ROI cursor which demonstrated 3 H.U. (mean) in plain CT, 32.2 H.U. (mean) in CE-CT, and 55.4 H.U. (mean) in CT-Angio respectively. In addition to this, the vessels adjacent to the pancreas, including superior mesenteric, splenic, and portal vein were also highly enhanced, demonstrating the irregularity or occluation when tumor invasion was present. And this indicated the useful role of CT-Angio in the diagnosis of the vascular involvement of pancreas carcinoma. CT-Angio was experimentally detectable the tumor as small as 2 cm in dog pancreas, which prepared with intraparenchymal injection of cyanoacrylate through a fine needle. From these results; we considered CT-Angio is essential not only in the detection of early pancreatic carcinoma, but also in the diagnosis of its tumor-extent. (author)

  12. The reliability and validity of passive leg raise and fluid bolus to assess fluid responsiveness in spontaneously breathing emergency department patients

    Duus, Nicolaj; Shogilev, Daniel J; Skibsted, Simon;

    2015-01-01

    : Prospective, observational study of a convenience sample of adult ED patients receiving intravenous fluid bolus. We assessed stroke volume (SV) using NICOM and obtained results from PLR, where the head of the bed was changed from semirecumbent to supine while the patients' legs raised to 45° for 3 minutes...

  13. Predicting erythroid response to recombinant erythropoietin plus granulocyte colony-stimulating factor therapy following a single subcutaneous bolus in patients with myelodysplasia

    BOWEN, D; Hyslop, A.; Keenan, N.; Groves, M.; Culligan, D.; Johnson, P; Shaw, A.; Geddes, F.; Evans, P.; Porter, J.; Cavill, I.

    2006-01-01

    We randomized 21 patients with low-risk myelodysplastic syndromes (MDS) to receive a single subcutaneous bolus of recombinant erythropoietin (epoietin) +/- granulocyte-colony stimulating factor (G-CSF), or placebo and monitored erythropoietic response over 7 days. In this small study, the reticulocyte response at day 7 was highly predictive of subsequent response to a therapeutic trial of epoietin + G-CSF.

  14. Automatic measurement of contrast bolus distribution in carotid arteries using a C-arm angiography system to support interventional perfusion imaging

    Fieselmann, Andreas; Ganguly, Arundhuti; Yu, Deuerling-Zheng; Boese, Jan; Hornegger, Joachim; Fahrig, Rebecca

    2011-03-01

    Brain perfusion CT using a C-arm angiography system capable of CT-like imaging could optimize patient treatment during stroke therapy procedures. For this application, an intra-arterial contrast bolus injection at the aortic arch could be used provided that the location of the injection catheter enables uniform distribution of the bolus into the two common carotid arteries (CCA). In this work, we present a novel method to support optimal injection catheter placement by providing additional quantitative information about the distribution of the contrast bolus into the CCAs. Our fully automatic method uses 2-D digital subtraction angiography (DSA) images following a test bolus injection. It segments both CCAs and computes the relative contrast distribution. We have tested the method in DSA data sets from 5 healthy pigs and our method achieved successful segmentation of both CCAs in all data sets. The results showed that the contrast is uniformly distributed (mean relative difference less or equal than 10%) if the injection location is properly chosen.

  15. Monte-Carlo-Model for the aerosol bolus dispersion in the human lung. Part 2. Model predictions for the diseased lung

    After a mathematical extension of the existing model for the theoretical description of the aerosol bolus dispersion, the behavior of particle pulses in diseased lung structures was simulated. The geometry used for healthy lungs was modified in two aspects: First, a modelling of possible airway obstructions, which usually occur in patients with chronic bronchitis, chronic asthma or cystic fibrosis, was carried out and, second, a theoretical approximation of the emphysema, being observed in lungs of smokers, but also as an accompanying phenomenon in obstructive diseases, was established. According to the modified model, in lungs with airway obstructions the exhaled bolus exhibited a decreased dispersion with respect to healthy subjects, whereas in emphysematous lungs the respective half-width of the peak was increased. Standard deviation and skewness of the bolus were similarly influenced by the modified lung architecture. A combination of airway obstruction and emphysema caused an extensive compensation of individual dispersion effects, complicating a secure distinction from the healthy lung. According to the model, a special diagnostic value may be assigned to the bolus deposition, showing significant deviations from the normal case for all simulated diseases. (orig.)

  16. An inter-observer study of the bolus-and-burst method for analysing pancreatic perfusion by contrast-enhanced ultrasound

    Stangeland, M.; Engjom, T.; Mézl, M.; Jiřík, Radovan; Gilja, O.H.; Dimcevski, G.; Nylund, K.

    Bergen : Allkopi, 2015, s. 82-85. ISBN 978-82-998920-5-6. [MedViz Conference 2015. Innovation in Imaging and Visualization. Bergen (NO), 15.06.2015-16.06.2015] Institutional support: RVO:68081731 Keywords : ultrasound perfusion analysis * bolus and burst method * blood volume * blood flow * mean transit time Subject RIV: BH - Optics, Masers, Lasers

  17. Split-bolus single-phase cardiac multidetector computed tomography for reliable detection of left atrial thrombus. Comparison to transesophageal echocardiography

    Evaluation of a new cardiac MDCT protocol using a split-bolus contrast injection protocol and single MDCT scan for reliable diagnosis of LA/LAA thrombi in comparison to TEE, optimizing radiation exposure and use of contrast agent. A total of 182 consecutive patients with drug refractory AF scheduled for PVI (62.6% male, mean age: 64.1 ± 10.2 years) underwent routine diagnostic work including TEE and cardiac MDCT for the evaluation of LA/LAA anatomy and thrombus formation between November 2010 and March 2012. Contrast media injection was split into a pre-bolus of 30 ml and main bolus of 70 ml iodinated contrast agent separated by a short time delay. In this study, split-bolus cardiac MDCT identified 14 of 182 patients with filling defects of the LA/LAA. In all of these 14 patients, abnormalities were found in TEE. All 5 of the 14 patients with thrombus formation in cardiac MDCT were confirmed by TEE. MDCT was 100% accurate for thrombus, with strong but not perfect overall results for SEC equivalent on MDCT.

  18. Split-bolus single-phase cardiac multidetector computed tomography for reliable detection of left atrial thrombus. Comparison to transesophageal echocardiography

    Staab, W.; Zwaka, P.A.; Sohns, J.M.; Schwarz, A.; Lotz, J. [University Medical Center Goettingen Univ. (Germany). Inst. for Diagnostic and Interventional Radiology; Sohns, C.; Vollmann, D.; Zabel, M.; Hasenfuss, G. [Goettingen Univ. (Germany). Dept. of Cardiology and Pneumology; Schneider, S. [Goettingen Univ. (Germany). Dept. of Medical Statistics

    2014-11-15

    Evaluation of a new cardiac MDCT protocol using a split-bolus contrast injection protocol and single MDCT scan for reliable diagnosis of LA/LAA thrombi in comparison to TEE, optimizing radiation exposure and use of contrast agent. A total of 182 consecutive patients with drug refractory AF scheduled for PVI (62.6% male, mean age: 64.1 ± 10.2 years) underwent routine diagnostic work including TEE and cardiac MDCT for the evaluation of LA/LAA anatomy and thrombus formation between November 2010 and March 2012. Contrast media injection was split into a pre-bolus of 30 ml and main bolus of 70 ml iodinated contrast agent separated by a short time delay. In this study, split-bolus cardiac MDCT identified 14 of 182 patients with filling defects of the LA/LAA. In all of these 14 patients, abnormalities were found in TEE. All 5 of the 14 patients with thrombus formation in cardiac MDCT were confirmed by TEE. MDCT was 100% accurate for thrombus, with strong but not perfect overall results for SEC equivalent on MDCT.

  19. ATTENUATION OF HAEMODYNAMIC RESPONSES TO LARYNGOSCOPY AND ENDOTRACHEAL INTUBATION: ROLE OF I.V. BOLUS DOSE OF ESMOLOL HYDROCHLORIDE AND LIGNOCAINE HYDROCHLORIDE : A COMPARATIVE STUDY

    Padma; Mydhili

    2015-01-01

    AIM: The aim of the study is to compare the efficacy of intravenous Bolus dose of Esmolol Hydrochloride and Lignocaine Hydrochloride to attenuate the Haemodynamic responses to Laryngoscopy and Endotracheal intubation. MATERIALS & METHODS : A study of Esmolol hydrochloride and Lignocaine hydrochloride in attenuation of the cardiovascular respons e during Laryngoscopy and intubation was compared in 50 adult patient, undergoing s...

  20. Adaptive Lighting

    Petersen, Kjell Yngve; Søndergaard, Karin; Kongshaug, Jesper

    2015-01-01

    Adaptive Lighting Adaptive lighting is based on a partial automation of the possibilities to adjust the colour tone and brightness levels of light in order to adapt to people’s needs and desires. IT support is key to the technical developments that afford adaptive control systems. The possibilities...... offered by adaptive lighting control are created by the ways that the system components, the network and data flow can be coordinated through software so that the dynamic variations are controlled in ways that meaningfully adapt according to people’s situations and design intentions. This book discusses...... the investigations of lighting scenarios carried out in two test installations: White Cube and White Box. The test installations are discussed as large-scale experiential instruments. In these test installations we examine what could potentially occur when light using LED technology is integrated and...

  1. Adaptive skills

    Staša Stropnik

    2013-02-01

    Full Text Available Adaptive skills are defined as a collection of conceptual, social and practical skills that are learned by people in order to function in their everyday lives. They include an individual's ability to adapt to and manage her or his surroundings to effectively function and meet social or community expectations. Good adaptive skills promote individual's independence in different environments, whereas poorly developed adaptive skills are connected to individual's dependency and with greater need for control and help with everyday tasks. Assessment of adaptive skills is often connected to assessment of intellectual disability, due to the reason that the diagnosis of intellectual disability includes lower levels of achievements on standardized tests of intellectual abilities as well as important deficits in adaptive skills. Assessment of adaptive behavior is a part of standard assessment battery with children and adults with different problems, disorders or disabilities that affect their everyday functioning. This contribution also presents psychometric tools most regularly used for assessment of adaptive skills and characteristics of adaptive skills with individual clinical groups.

  2. ADAPT Dataset

    National Aeronautics and Space Administration — Advanced Diagnostics and Prognostics Testbed (ADAPT) Project Lead: Scott Poll Subject Fault diagnosis in electrical power systems Description The Advanced...

  3. SU-E-T-356: Accuracy of Eclipse Electron Macro Monte Carlo Dose Algorithm for Use in Bolus Electron Conformal Therapy

    Purpose: To evaluate the accuracy of electron dose distribution calculated by the Varian Eclipse electron Monte Carlo (eMC) algorithm for use with recent commercially available bolus electron conformal therapy (ECT). Methods: eMC-calculated electron dose distributions for bolus ECT have been compared to those previously measured for cylindrical phantoms (retromolar trigone and nose), whose axial cross sections were based on the mid-PTV CT anatomy for each site. The phantoms consisted of SR4 muscle substitute, SR4 bone substitute, and air. The bolus ECT treatment plans were imported into the Eclipse treatment planning system and calculated using the maximum allowable histories (2×109), resulting in a statistical error of <0.2%. Smoothing was not used for these calculations. Differences between eMC-calculated and measured dose distributions were evaluated in terms of absolute dose difference as well as distance to agreement (DTA). Results: Results from the eMC for the retromolar trigone phantom showed 89% (41/46) of dose points within 3% dose difference or 3 mm DTA. There was an average dose difference of −0.12% with a standard deviation of 2.56%. Results for the nose phantom showed 95% (54/57) of dose points within 3% dose difference or 3 mm DTA. There was an average dose difference of 1.12% with a standard deviation of 3.03%. Dose calculation times for the retromolar trigone and nose treatment plans were 15 min and 22 min, respectively, using 16 processors (Intel Xeon E5-2690, 2.9 GHz) on a Varian Eclipse framework agent server (FAS). Results of this study were consistent with those previously reported for accuracy of the eMC electron dose algorithm and for the .decimal, Inc. pencil beam redefinition algorithm used to plan the bolus. Conclusion: These results show that the accuracy of the Eclipse eMC algorithm is suitable for clinical implementation of bolus ECT

  4. Performance of a Chase-type decoding algorithm for Reed-Solomon codes on perpendicular magnetic recording channels

    Wang, H.; Chang, W.; Cruz, J. R.

    Algebraic soft-decision Reed-Solomon (RS) decoding algorithms with improved error-correcting capability and comparable complexity to standard algebraic hard-decision algorithms could be very attractive for possible implementation in the next generation of read channels. In this work, we investigate the performance of a low-complexity Chase (LCC)-type soft-decision RS decoding algorithm, recently proposed by Bellorado and Kavčić, on perpendicular magnetic recording channels for sector-long RS codes of practical interest. Previous results for additive white Gaussian noise channels have shown that for a moderately long high-rate code, the LCC algorithm can achieve a coding gain comparable to the Koetter-Vardy algorithm with much lower complexity. We present a set of numerical results that show that this algorithm provides small coding gains, on the order of a fraction of a dB, with similar complexity to the hard-decision algorithms currently used, and that larger coding gains can be obtained if we use more test patterns, which significantly increases its computational complexity.

  5. Chase Sound Boys Out of Earth”: The Aura of Dubplate Specials in Finnish Reggae Sound System Culture

    Kim Ramstedt

    2015-11-01

    Full Text Available This study seeks to expand our understanding of how dubplate specials are produced, circulated, and culturally valued in the international reggae sound system culture of the dub diaspora by analysing the production and performance of “Chase the Devil” (2005, a dubplate special commissioned by the Finnish MPV sound system from Jamaican reggae singer Max Romeo. A dubplate special is a unique recording where, typically, a reggae artist re-records the vocals to one of his or her popular songs with new lyrics that praise the sound system that commissioned the recording. Scholars have previously theorized dubplates using Walter Benjamin’s concept of aura, thereby drawing attention to the exclusivity and uniqueness of these traditionally analog recordings. However, since the advent of digital technologies in both recording and sound system performance, what Benjamin calls the “cult value” of producing and performing dubplates has become increasingly complex and multi-layered, as digital dubplates now remediate prior aesthetic forms of the analog. By turning to ethnographic accounts from the sound system’s DJ selectors, I investigate how digital dubplates are still culturally valued for their aura, even as the very concept of aura falls into question when applied to the recording and performance of digital dubplates.

  6. The regeneration of a multi-ethnic mixed-use area: The case of Robin Hood Chase

    Ian Bentley

    1997-01-01

    Full Text Available Urban designers show increasing interest in promoting community participation in urban regeneration and especially housing regeneration. However, effective participation has proved difficult in multi-ethnic mixed-use areas, with their wide range of different (and often conflicting interest groups. This paper, presented in case-study form, analyses a project in one such area: the Robin Hood Chase local centre in St. Ann’s area of Nottingham. It pays particular attention to the identification of different interest groups and their associated institutions, the use of local media and social events to involve these groups in the urban design process, the use of rearrangeable models in a process of “enquiry by design”, and the production of a widely acceptable urban design strategy for the area. Analysis of feedback from participants indicates a high level of satisfaction both with the final physical design proposal and with the process itself; and also identifies directions for further development in the approach and techniques employed.

  7. Plasma level monitoring of the major metabolites of diacetylmorphine (heroin) by the "chasing the dragon" route in severe heroin addicts.

    Dubois, N; Demaret, I; Ansseau, M; Rozet, E; Hubert, Ph; Charlier, C

    2013-01-01

    The objective of the present study was to verify if severe physical health problems frequently encountered in heroin addicts and the concomitant use of alcohol and legal or illegal drugs other than heroin influenced the pharmacokinetics of the major metabolites of heroin. We conducted a 90 minutes follow-up of the plasma concentrations of the pharmaceutical heroin, named diacetylmorphine (DAM), in patients recruited in a DAM assisted treatment centre. TADAM (Traitement Assisté par DiAcétylMorphine) aimed to compare the efficacy of heroin-assisted treatment (HAT) compared with methadone maintenance treatment (MMT) for heroin users considered as treatment resistant patients and who have severe physical and mental health problems. Eleven patients were recruited. Blood samples were collected at baseline and 15, 45 and 90 minutes after DAM administration. All patients received DAM by the "chasing the dragon" route. Plasma samples were analyzed by a previously described ultra-high pressure liquid chromatography coupled to tandem mass spectrometry (UHPLC/MS-MS) method. A principal component analysis (PCA) was performed and 8 metabolite concentrations ratios were calculated to evaluate the influence of various factors (DAM dose, patient pathologies, concomitant use of medications, methadone, street heroin, alcohol and cocaine) on heroin metabolite pharmacokinetics. It seemed to be not affected by the DAM dose, patient pathologies and the concomitant use of medications, methadone, street heroin and alcohol. Cocaine use was the only parameter which showed differences in heroin pharmacokinetics. PMID:24579243

  8. The Nudix Hydrolase CDP-Chase, a CDP-Choline Pyrophosphatase, Is an Asymmetric Dimer with Two Distinct Enzymatic Activities

    Duong-Ly, Krisna C.; Gabelli, Sandra B.; Xu, WenLian; Dunn, Christopher A.; Schoeffield, Andrew J.; Bessman, Maurice J.; Amzel, L. Mario (Loyola); (JHU)

    2011-09-06

    A Nudix enzyme from Bacillus cereus catalyzes the hydrolysis of CDP-choline to produce CMP and phosphocholine. Here, we show that in addition, the enzyme has a 3{prime} {yields} 5{prime} RNA exonuclease activity. The structure of the free enzyme, determined to a 1.8-{angstrom} resolution, shows that the enzyme is an asymmetric dimer. Each monomer consists of two domains, an N-terminal helical domain and a C-terminal Nudix domain. The N-terminal domain is placed relative to the C-terminal domain such as to result in an overall asymmetric arrangement with two distinct catalytic sites: one with an 'enclosed' Nudix pyrophosphatase site and the other with a more open, less-defined cavity. Residues that may be important for determining the asymmetry are conserved among a group of uncharacterized Nudix enzymes from Gram-positive bacteria. Our data support a model where CDP-choline hydrolysis is catalyzed by the enclosed Nudix site and RNA exonuclease activity is catalyzed by the open site. CDP-Chase is the first identified member of a novel Nudix family in which structural asymmetry has a profound effect on the recognition of substrates.

  9. Fifty years of chasing lizards: new insights advance optimal escape theory.

    Samia, Diogo S M; Blumstein, Daniel T; Stankowich, Theodore; Cooper, William E

    2016-05-01

    Systematic reviews and meta-analyses often examine data from diverse taxa to identify general patterns of effect sizes. Meta-analyses that focus on identifying generalisations in a single taxon are also valuable because species in a taxon are more likely to share similar unique constraints. We conducted a comprehensive phylogenetic meta-analysis of flight initiation distance in lizards. Flight initiation distance (FID) is a common metric used to quantify risk-taking and has previously been shown to reflect adaptive decision-making. The past decade has seen an explosion of studies focused on quantifying FID in lizards, and, because lizards occur in a wide range of habitats, are ecologically diverse, and are typically smaller and differ physiologically from the better studied mammals and birds, they are worthy of detailed examination. We found that variables that reflect the costs or benefits of flight (being engaged in social interactions, having food available) as well as certain predator effects (predator size and approach speed) had large effects on FID in the directions predicted by optimal escape theory. Variables that were associated with morphology (with the exception of crypsis) and physiology had relatively small effects, whereas habitat selection factors typically had moderate to large effect sizes. Lizards, like other taxa, are very sensitive to the costs of flight. PMID:25620002

  10. Case studies in quantitative biology: Biochemistry on a leash and a single-molecule Hershey-Chase experiment

    Van Valen, David

    2011-12-01

    The last 50 years of biological research has seen a marked increase in the amount of quantitative data that describes living systems. This wealth of data provides a unique opportunity to recast the pictorial level descriptions of biological processes in the language of mathematics, with the hope that such an undertaking will lead to deeper insights into the behavior of living systems. To achieve this end, we have undertaken three case studies in physical biology. In the first case study, we used statistical mechanics and polymer physics to construct a simple model that describes how flexible chains of amino acids, referred to as tethers, influence the information processing properties of signaling proteins. In the second case study, we studied the DNA ejection process of phage lambda in vitro. In particular, we used bulk and single-molecule methods to study the control parameters that govern the force and kinematics of the ejection process in vitro. In the last case study, we studied the DNA ejection process of phage lambda in vivo. We developed an assay that allows real-time monitoring of DNA ejection in vivo at the single-molecule level. We also developed a parallel system that allows the simultaneous visualization of both phage capsids and phage DNA at the single-cell level, constituting a true single-molecule Hershey-Chase experiment. The work described in this thesis outlines new tools, both in theory and experiment, that can be used to study biological systems as well as a paradigm that can be employed to mathematicize the cartoons of biology.

  11. Ambiguous Adaptation

    Møller Larsen, Marcus; Lyngsie, Jacob

    We investigate why some exchange relationships terminate prematurely. We argue that investments in informal governance structures induce premature termination in relationships already governed by formal contracts. The formalized adaptive behavior of formal governance structures and the flexible and...... reciprocal adaptation of informal governance structure create ambiguity in situations of contingencies, which, subsequently, increases the likelihood of premature relationship termination. Using a large sample of exchange relationships in the global service provider industry, we find support for a hypothesis...

  12. Strategic Adaptation

    Andersen, Torben Juul

    2015-01-01

    This article provides an overview of theoretical contributions that have influenced the discourse around strategic adaptation including contingency perspectives, strategic fit reasoning, decision structure, information processing, corporate entrepreneurship, and strategy process. The related...... concepts of strategic renewal, dynamic managerial capabilities, dynamic capabilities, and strategic response capabilities are discussed and contextualized against strategic responsiveness. The insights derived from this article are used to outline the contours of a dynamic process of strategic adaptation...

  13. Is adaptation. Truly an adaptation? Is adaptation. Truly an adaptation?

    Thais Flores Nogueira Diniz

    2008-04-01

    Full Text Available The article begins by historicizing film adaptation from the arrival of cinema, pointing out the many theoretical approaches under which the process has been seen: from the concept of “the same story told in a different medium” to a comprehensible definition such as “the process through which works can be transformed, forming an intersection of textual surfaces, quotations, conflations and inversions of other texts”. To illustrate this new concept, the article discusses Spike Jonze’s film Adaptation. according to James Naremore’s proposal which considers the study of adaptation as part of a general theory of repetition, joined with the study of recycling, remaking, and every form of retelling. The film deals with the attempt by the scriptwriter Charles Kaufman, cast by Nicholas Cage, to adapt/translate a non-fictional book to the cinema, but ends up with a kind of film which is by no means what it intended to be: a film of action in the model of Hollywood productions. During the process of creation, Charles and his twin brother, Donald, undergo a series of adventures involving some real persons from the world of film, the author and the protagonist of the book, all of them turning into fictional characters in the film. In the film, adaptation then signifies something different from itstraditional meaning. The article begins by historicizing film adaptation from the arrival of cinema, pointing out the many theoretical approaches under which the process has been seen: from the concept of “the same story told in a different medium” to a comprehensible definition such as “the process through which works can be transformed, forming an intersection of textual surfaces, quotations, conflations and inversions of other texts”. To illustrate this new concept, the article discusses Spike Jonze’s film Adaptation. according to James Naremore’s proposal which considers the study of adaptation as part of a general theory of repetition

  14. Comparison of first pass bolus AIFs extracted from sequential 18F-FDG PET and DSC-MRI of mice

    Accurate kinetic modelling of in vivo physiological function using positron emission tomography (PET) requires determination of the tracer time–activity curve in plasma, known as the arterial input function (AIF). The AIF is usually determined by invasive blood sampling methods, which are prohibitive in murine studies due to low total blood volumes. Extracting AIFs from PET images is also challenging due to large partial volume effects (PVE). We hypothesise that in combined PET with magnetic resonance imaging (PET/MR), a co-injected bolus of MR contrast agent and PET ligand can be tracked using fast MR acquisitions. This protocol would allow extraction of a MR AIF from MR contrast agent concentration–time curves, at higher spatial and temporal resolution than an image-derived PET AIF. A conversion factor could then be applied to the MR AIF for use in PET kinetic analysis. This work has compared AIFs obtained from sequential DSC-MRI and PET with separate injections of gadolinium contrast agent and 18F-FDG respectively to ascertain the technique′s validity. An automated voxel selection algorithm was employed to improve MR AIF reproducibility. We found that MR and PET AIFs displayed similar character in the first pass, confirmed by gamma variate fits (p<0.02). MR AIFs displayed reduced PVE compared to PET AIFs, indicating their potential use in PET/MR studies

  15. Regional cerebral blood flow measurement with intravenous [15O]water bolus and [18F]fluoromethane inhalation

    In 20 patients with ischemic cerebrovascular disease, classic migraine, or angiomas, we compared paired dynamic positron emission tomographic measurements of regional cerebral blood flow using both [15O]water and [18F]fluoromethane as tracers. Cerebral blood flow was also determined according to the autoradiographic technique with a bolus injection of [15O]water. There were reasonable overall correlations between dynamic [15O]water and [18F]fluoromethane values for cerebral blood flow (r = 0.82) and between dynamic and autoradiographic [15O]water values for cerebral blood flow (r = 0.83). We found a close correspondence between abnormal pathologic findings and visually evaluated cerebral blood flow tomograms obtained with the two tracers. On average, dynamic [15O]water cerebral blood flow was 6% lower than that measured with [18F]fluoromethane. There also was a general trend toward a greater underestimation with [15O]water in high-flow areas, particularly in hyperemic areas, probably due to incomplete first-pass extraction of [15O]water. Underestimation was not detected in low-flow areas or in the cerebellum. Absolute cerebral blood flow values were less closely correlated between tracers and techniques than cerebral blood flow patterns. The variability of the relation between absolute flow values was probably caused by confounding effects of the variation in the circulatory delay time. The autoradiographic technique was most sensitive to this type error

  16. Bolus arrival time and its effect on tissue characterization with dynamic contrast-enhanced magnetic resonance imaging.

    Mehrtash, Alireza; Gupta, Sandeep N; Shanbhag, Dattesh; Miller, James V; Kapur, Tina; Fennessy, Fiona M; Kikinis, Ron; Fedorov, Andriy

    2016-01-01

    Matching the bolus arrival time (BAT) of the arterial input function (AIF) and tissue residue function (TRF) is necessary for accurate pharmacokinetic (PK) modeling of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). We investigated the sensitivity of volume transfer constant ([Formula: see text]) and extravascular extracellular volume fraction ([Formula: see text]) to BAT and compared the results of four automatic BAT measurement methods in characterization of prostate and breast cancers. Variation in delay between AIF and TRF resulted in a monotonous change trend of [Formula: see text] and [Formula: see text] values. The results of automatic BAT estimators for clinical data were all comparable except for one BAT estimation method. Our results indicate that inaccuracies in BAT measurement can lead to variability among DCE-MRI PK model parameters, diminish the quality of model fit, and produce fewer valid voxels in a region of interest. Although the selection of the BAT method did not affect the direction of change in the treatment assessment cohort, we suggest that BAT measurement methods must be used consistently in the course of longitudinal studies to control measurement variability. PMID:26989759

  17. Comparative study of intravenous urographic bolus (I.U.B.) and intravenous urographic infusion (I.U.I.) in dogs

    Two urographic methods were compared: the intravenous urographic bolus (i.u.b.) and the intravenous urographic infusion (i.u.i.). In both methods, two groups of seven healthy adult dogs of both sexes, weighing7.0 to 16.5 kg were used and were anaesthesized with 2% thiopentone sodium in doses of 20 mg/kg via cephalica. In the i.u.b., meglumine diatrizoate (Hypaque-M, 60%) was injected via saphena with a concentration of 282 mg of iodine per mi in doses of 564 mg of iodine per kg. In the i.u.i., meglumine diatrizoate was injected via saphena by drip infusion with a concentration of 200 mg of iodine per mi in doses of 500 mg of iodine per kg. Three series of two X-rays each were taken in ventrodorsal projection 1, 4 and 8 min and left lateral recumbency 30 sec after administering the contrast medium. The X-ray plates obtained were analyzed and compared intra and inter group considering the advance speed of the contrast medium, the radiographic density and outline, and kidney size. The advance speed of the contrast medium was higher in the i.u.i., reaching the kidney, ureter and bladder 1 min after administration in both projections; in ventrodorsal projections in the i.u.b. only the kidneys were reached while in the left lateral recumbency, the kidney and ureters were reached

  18. Dose Regimens, Variability, and Complications Associated with Using Repeat-Bolus Dosing to Extend a Surgical Plane of Anesthesia in Laboratory Mice

    Jaber, Samer M.; Hankenson, F Claire; Heng, Kathleen; McKinstry-Wu, Andrew; Kelz, Max B.; Marx, James O

    2014-01-01

    Extending a surgical plane of anesthesia in mice by using injectable anesthetics typically is accomplished by repeat-bolus dosing. We compared the safety and efficacy of redosing protocols administered either during an anesthetic surgical plane (maintaining a continuous surgical plane, CSP), or immediately after leaving this plane (interrupted surgical plane, ISP) in C57BL/6J mice. Anesthesia was induced with ketamine, xylazine, and acepromazine (80, 8, and 1 mg/kg IP, respectively), and redo...

  19. SU-D-18C-05: Variable Bolus Arterial Spin Labeling MRI for Accurate Cerebral Blood Flow and Arterial Transit Time Mapping

    Johnston, M; Jung, Y [Wake Forest School of Medicine, Winston-Salem, NC (United States)

    2014-06-01

    Purpose: Arterial spin labeling (ASL) is an MRI perfusion imaging method from which quantitative cerebral blood flow (CBF) maps can be calculated. Acquisition with variable post-labeling delays (PLD) and variable TRs allows for arterial transit time (ATT) mapping and leads to more accurate CBF quantification with a scan time saving of 48%. In addition, T1 and M0 maps can be obtained without a separate scan. In order to accurately estimate ATT and T1 of brain tissue from the ASL data, variable labeling durations were invented, entitled variable-bolus ASL. Methods: All images were collected on a healthy subject with a 3T Siemens Skyra scanner. Variable-bolus Psuedo-continuous ASL (PCASL) images were collected with 7 TI times ranging 100-4300ms in increments of 700ms with TR ranging 1000-5200ms. All boluses were 1600ms when the TI allowed, otherwise the bolus duration was 100ms shorter than the TI. All TI times were interleaved to reduce sensitivity to motion. Voxel-wise T1 and M0 maps were estimated using a linear least squares fitting routine from the average singal from each TI time. Then pairwise subtraction of each label/control pair and averaging for each TI time was performed. CBF and ATT maps were created using the standard model by Buxton et al. with a nonlinear fitting routine using the T1 tissue map. Results: CBF maps insensitive to ATT were produced along with ATT maps. Both maps show patterns and averages consistent with literature. The T1 map also shows typical T1 contrast. Conclusion: It has been demonstrated that variablebolus ASL produces CBF maps free from the errors due to ATT and tissue T1 variations and provides M0, T1, and ATT maps which have potential utility. This is accomplished with a single scan in a feasible scan time (under 6 minutes) with low sensivity to motion.

  20. SU-D-18C-05: Variable Bolus Arterial Spin Labeling MRI for Accurate Cerebral Blood Flow and Arterial Transit Time Mapping

    Purpose: Arterial spin labeling (ASL) is an MRI perfusion imaging method from which quantitative cerebral blood flow (CBF) maps can be calculated. Acquisition with variable post-labeling delays (PLD) and variable TRs allows for arterial transit time (ATT) mapping and leads to more accurate CBF quantification with a scan time saving of 48%. In addition, T1 and M0 maps can be obtained without a separate scan. In order to accurately estimate ATT and T1 of brain tissue from the ASL data, variable labeling durations were invented, entitled variable-bolus ASL. Methods: All images were collected on a healthy subject with a 3T Siemens Skyra scanner. Variable-bolus Psuedo-continuous ASL (PCASL) images were collected with 7 TI times ranging 100-4300ms in increments of 700ms with TR ranging 1000-5200ms. All boluses were 1600ms when the TI allowed, otherwise the bolus duration was 100ms shorter than the TI. All TI times were interleaved to reduce sensitivity to motion. Voxel-wise T1 and M0 maps were estimated using a linear least squares fitting routine from the average singal from each TI time. Then pairwise subtraction of each label/control pair and averaging for each TI time was performed. CBF and ATT maps were created using the standard model by Buxton et al. with a nonlinear fitting routine using the T1 tissue map. Results: CBF maps insensitive to ATT were produced along with ATT maps. Both maps show patterns and averages consistent with literature. The T1 map also shows typical T1 contrast. Conclusion: It has been demonstrated that variablebolus ASL produces CBF maps free from the errors due to ATT and tissue T1 variations and provides M0, T1, and ATT maps which have potential utility. This is accomplished with a single scan in a feasible scan time (under 6 minutes) with low sensivity to motion

  1. Effects of Bolus and Continuous Nasogastric Feeding on Gastric Emptying, Small Bowel Water Content, Superior Mesenteric Artery Blood Flow, and Plasma Hormone Concentrations in Healthy Adults

    Chowdhury, Abeed H.; Murray, Kathryn; Hoad, Caroline L.; Costigan, Carolyn; Marciani, Luca; Macdonald, Ian A.; Bowling, Timothy E.; Lobo, Dileep N

    2016-01-01

    Objective: We aimed to demonstrate the effect of continuous or bolus nasogastric feeding on gastric emptying, small bowel water content, and splanchnic blood flow measured by magnetic resonance imaging (MRI) in the context of changes in plasma gastrointestinal hormone secretion. Background: Nasogastric/nasoenteral tube feeding is often complicated by diarrhea but the contribution of feeding strategy to the etiology is unclear. Methods: Twelve healthy adult male participants who underwent naso...

  2. Cost comparison of insulin glargine with insulin detemir in a basal-bolus regime with mealtime insulin aspart in type 2 diabetes in Germany

    Dippel, Franz-Werner

    2010-01-01

    Full Text Available Objective: To compare the treatment costs of insulin glargine (IG; Lantus® to detemir (ID; Levemir®, both combined with bolus insulin aspart (NovoRapid® in type 2 diabetes (T2D in Germany. Methods: Cost comparison was based on data of a 1-year randomised controlled trial [1]. IG was administered once daily and ID once (57% of patients or twice daily (43% according to treatment response. At the end of the trial, mean daily basal insulin doses were 0.59 U/kg (IG and 0.82 U/kg (ID. Aspart doses were 0.32 U/kg (IG and 0.36 U/kg (ID. Costs were calculated from the German statutory health insurance (SHI perspective using official 2008 prices. Sensitivity analyses were performed to test robustness of the results. Results: Annual basal and bolus insulin costs per patient were € 1,473 (IG and € 1,940 (ID. The cost of lancets and blood glucose test strips were € 1,125 (IG and € 1,286 (ID. Annual costs for needles were € 393 (IG and € 449 (ID. The total annual cost per patient of administering IG was € 2,991 compared with € 3,675 for ID, translating into a 19% annual cost difference of € 684/patient. Base case results were robust to varying assumptions for insulin dose, insulin price, change in weight and proportion of ID once daily administrations. Conclusion: IG and ID basal-bolus regimes have comparative safety and efficacy, based on the Hollander study, IG however may represent a significantly more cost saving option for T2D patients in Germany requiring basal-bolus insulin analogue therapy with potential annual cost savings of € 684/patient compared to ID.

  3. Finns det nån här? – Förmedling av paranormala fenomen i TV-serien Chasing the Dead

    Heinänen, Thomas

    2013-01-01

    Genom denna kvalitativa innehållsanalys av TV-serien Chasing the Dead, undersöks på vilket sätt dokumenterade "bevis" på paranormala audiovisuella fenomen har presenterats av seriemakarna. Materialet analyseras med hjälp av forskningsresultat från, för denna TV-genre relevanta, studier av fenomen som Electronic Voice Phenomenon, Electro Magnetic Field, Orber. Biologiska fenomen som Apophenia och Pareidolia har tagits i beaktande då materialet har analyserats. Syftet med denna underso...

  4. Biphasic Insulin Aspart 30/70: Pharmacokinetics and Pharmacodynamics Compared With Once-Daily Biphasic Human Insulin and Basal-Bolus Therapy

    Heise, Tim; Heinemann, Lutz; Hövelmann, Ulrike; Brauns, Bianca; Nosek, Leszek; Haahr, Hanne L.; Olsen, Klaus J.

    2009-01-01

    OBJECTIVE Pharmacological profiles of biphasic insulin aspart 30/70 (BIAsp 30) once daily (OD), twice daily (b.i.d.), and three times daily (t.i.d.) were compared with other insulin regimens in two crossover glucose clamp studies of insulin-treated type 2 diabetic patients. RESEARCH DESIGNS AND METHODS Study 1 consisted of BIAsp 30 OD, b.i.d., and t.i.d. versus biphasic human insulin 30/70 (BHI 30), OD (n = 24). Study 2 examined BIAsp 30 t.i.d. versus basal-bolus therapy (insulin glargine OD plus insulin glulisine t.i.d.) (n = 24). Pharmacokinetics/pharmacodynamics (PK/PD) were investigated over 24 h. RESULTS Study 1: PK and PD were markedly different between BIAsp 30 OD and BHI 30 OD: the maximum insulin concentration and glucose infusion rate (GIR) were higher for BIAsp 30; time to maximum metabolism was 1.7 h sooner for BIAsp 30. Study 2: both regimens showed three distinct prandial-related GIR peaks. GIR 24-h area under the curve for BIAsp t.i.d. was higher than for basal-bolus therapy: 2,585.2 vs. 2,289.2 mg/kg. CONCLUSIONS BIAsp had pharmacological advantages over BHI. BIAsp t.i.d. had a similar PD profile to basal-bolus therapy. PMID:19487640

  5. Effects of maintenance of propofol-ketamine anesthesia with repeat bolus and constant rate infusion of propofol on physiological, biochemical, anesthetic and analgesic indices in dogs

    Njoku Uchechukwu Njoku

    2015-12-01

    Full Text Available The research work was aimed at investigating physiological, biochemical, analgesic and anesthetic indices of dogs anesthetized with propofol-ketamine and maintained with repeat bolus and constant infusions of propofol. Eight dogs, assigned to two groups (n=4, were used in this study. All dogs were pre-medicated with atropine (at 0.03 mg/kg bwt and xylazine (at 2 mg/kg bwt. Anesthesia was induced by a concurrent administration of propofol (at 4 mg/kg bwt and ketamine (at 2.5 mg/kg bwt. Maintenance of anesthesia in Group 1 was done with a repeat bolus of propofol (at 2 mg/kg bwt, while in Group 2 it was done with a constant infusion of propofol (at 0.2 mg/kg bwt/min. Gastrotomy was performed in both groups, and anesthesia was maintained for 60 min. Physiological, analgesic, anesthetic parameters and plasma glucose concentration were measured. There was no significant (P>0.05 difference found in the analgesia and pedal reflex scores, durations of analgesia and recumbency, recovery time and standing time between the groups. The heart rate, respiratory rate and rectal temperature reduced significantly (P0.05 between the groups. In conclusion, both maintenance protocols are suitable for dogs, although the repeat bolus technique produces marked cardiopulmonary depression.

  6. Laser Stimulation of the Chloroplast/Endoplasmic Reticulum Nexus in Tobacco Transiently Produces Protein Aggregates (Boluses) within the Endoplasmic Reticulum and Stimulates Local ER Remodeling

    Lawrence R. Griffing

    2011-01-01

    Does the ER subdomain that associates with the chloroplast in vivo,hereafter referred to as the chloroplast/ER nexus,play a role in protein flow within the ER? In studies of tobacco cells either constitutively or transiently expressing ER-retained luminal,GFP-HDEL,or trans-membrane,YFP-RHD3,fluorescent fusion proteins,brief 405-nm (3-6-mW) laser stimulation of the nexus causes a qualitative difference in the movement and behavior of proteins in the ER.Photostimulating the nexus produces fluorescent protein punctate aggregates (boluses) within the lumen and membrane of the ER.The aggregation propagates through the membrane network throughout the cell,but within minutes can revert to normal,with disaggregation propagating back toward the originally photostimulated nexus.In the meantime,the ER grows and anastomoses around the chloroplast,forming a dense cisternal and tubular network.If this network is again photostimulated,bolus formation does not recur and,if the photostimulation results in photobleaching,fluorescence recovery after photobleaching occurs as it would typically in areas away from the nexus.Bolus propagation is not mediated by the actin cytoskeleton,but can be reversed by pre-conditioning the cells for 30 min with high,40-45℃,temperature (heat stress).Because it is not reversed with heat stress,the reorganization of the ER at the nexus following photostimulation is a separate event.

  7. Treatment of Advanced Gastric Carcinoma Patients with Calcium Folinate, a 5-Fluorouracil Bolus and Continous Infusion with 5-Infusion with 5-Fluorouracil Combined with Oxaliplatin

    Qilian Liang; Saihong Chen; Dachao Pan; Jierong Xie; Liangzhen Cai; Shujun Li

    2008-01-01

    OBJECTIVE To examine the therapeutic effects and toxicity of high-dose-folinic acid plus a 5-fluorouracil (5-FU) bolus and continuous infusion with 5-FU combined with locally produced oxaliplatin (L-HOP)in treating advanced gastric carcinoma patients.METHODS Sixty-five patients with advanced gastric carcinoma were treated with high-dose-folinic acid plus a 5-FU bolus and a 48-h continuous infusion of 5-FU combined with oxaliplatin. The effects of treatment and toxicity were observed.RESULTS There were 4 complete responses, 26 partial responses,30 with no change and 5 with progressive disease. The overall effective response rate was 46.2% (30/65). The median duration was 7 months, with the main side effects including nausea and vomiting, peripheral phlebitis, alopecia, leukopenia, dental ulcers,peripheral neuritis and diarrhea. All the side effects were tolerated and minimal.CONCLUSION The results showed that high-dose folinic acid plus a 5-FU bolus and continuous infusion of 5-FU combined with oxaliplatin appears to be a safe and effective therapy for patients with advanced gastric carcinoma. This therapeutic regimen is of value for these patients.

  8. Intracoronary Compared to Intravenous Bolus Abciximab during Primary Percutaneous Coronary Intervention in ST-segment Elevation Myocardial Infarction (STEMI) Patients Reduces 30-day Mortality and Target Vessel Revascularization: A Randomized Trial

    Iversen, Allan; Abildgaard, Ulrik; Galloe, Anders;

    2011-01-01

    Background: Abciximab is beneficial in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (pPCI). However, the optimal administration route of the initial bolus of abciximab, that is, intravenous (IV) versus intracoronary (IC), has...... been questioned. Preliminary studies suggest that IC-bolus is superior, probably due to high local concentration. In this study, we assess the short-term efficacy and safety of IC compared to IV bolus of abciximab in patients with STEMI during pPCI. Methods: In 2006-2008, we randomized 355 STEMI...... patients who underwent pPCI and had indication for abciximab to either IV or IC bolus followed by a 12-hour IV infusion. Primary end-points at 30 days were target vessel revascularization (TVR), recurrent myocardial infarction (MI) or death, and the composite of the three. Secondary end-points were...

  9. Adaptive test

    Kjeldsen, Lars Peter; Eriksen, Mette Rose

    2010-01-01

    Artikelen er en evaluering af de adaptive tests, som blev indført i folkeskolen. Artiklen sætter særligt fokus på evaluering i folkeskolen, herunder bidrager den med vejledning til evaluering, evalueringsværktøjer og fagspecifkt evalueringsmateriale.......Artikelen er en evaluering af de adaptive tests, som blev indført i folkeskolen. Artiklen sætter særligt fokus på evaluering i folkeskolen, herunder bidrager den med vejledning til evaluering, evalueringsværktøjer og fagspecifkt evalueringsmateriale....

  10. Monte Carlo characterization of skin doses in 6 MV transverse field MRI-linac systems: Effect of field size, surface orientation, magnetic field strength, and exit bolus

    Purpose: The main focus of this work is to continue investigations into the Monte Carlo predicted skin doses seen in MRI-guided radiotherapy. In particular, the authors aim to characterize the 70 μm skin doses over a larger range of magnetic field strength and x-ray field size than in the current literature. The effect of surface orientation on both the entry and exit sides is also studied. Finally, the use of exit bolus is also investigated for minimizing the negative effects of the electron return effect (ERE) on the exit skin dose. Methods: High resolution GEANT4 Monte Carlo simulations of a water phantom exposed to a 6 MV x-ray beam (Varian 2100C) have been performed. Transverse magnetic fields of strengths between 0 and 3 T have been applied to a 30x30x20 cm3 phantom. This phantom is also altered to have variable entry and exit surfaces with respect to the beam central axis and they range from -75 deg. to +75 deg. The exit bolus simulated is a 1 cm thick (water equivalent) slab located on the beam exit side. Results: On the entry side, significant skin doses at the beam central axis are reported for large positive surface angles and strong magnetic fields. However, over the entry surface angle range of -30 deg. to -60 deg., the entry skin dose is comparable to or less than the zero magnetic field skin dose, regardless of magnetic field strength and field size. On the exit side, moderate to high central axis skin dose increases are expected except at large positive surface angles. For exit bolus of 1 cm thickness, the central axis exit skin dose becomes an almost consistent value regardless of magnetic field strength or exit surface angle. This is due to the almost complete absorption of the ERE electrons by the bolus. Conclusions: There is an ideal entry angle range of -30 deg. to -60 deg. where entry skin dose is comparable to or less than the zero magnetic field skin dose. Other than this, the entry skin dose increases are significant, especially at higher

  11. Monte Carlo characterization of skin doses in 6 MV transverse field MRI-linac systems: Effect of field size, surface orientation, magnetic field strength, and exit bolus

    Oborn, B. M.; Metcalfe, P. E.; Butson, M. J.; Rosenfeld, A. B. [Illawarra Cancer Care Centre (ICCC), Wollongong, New South Wales 2500 (Australia) and Centre for Medical Radiation Physics (CMRP), University of Wollongong, Wollongong, New South Wales 2500 (Australia); Centre for Medical Radiation Physics (CMRP), University of Wollongong, Wollongong, New South Wales 2500 (Australia); Illawarra Cancer Care Centre (ICCC), Wollongong, New South Wales 2500 (Australia); Centre for Medical Radiation Physics (CMRP), University of Wollongong, Wollongong, New South Wales 2500 (Australia)

    2010-10-15

    Purpose: The main focus of this work is to continue investigations into the Monte Carlo predicted skin doses seen in MRI-guided radiotherapy. In particular, the authors aim to characterize the 70 {mu}m skin doses over a larger range of magnetic field strength and x-ray field size than in the current literature. The effect of surface orientation on both the entry and exit sides is also studied. Finally, the use of exit bolus is also investigated for minimizing the negative effects of the electron return effect (ERE) on the exit skin dose. Methods: High resolution GEANT4 Monte Carlo simulations of a water phantom exposed to a 6 MV x-ray beam (Varian 2100C) have been performed. Transverse magnetic fields of strengths between 0 and 3 T have been applied to a 30x30x20 cm{sup 3} phantom. This phantom is also altered to have variable entry and exit surfaces with respect to the beam central axis and they range from -75 deg. to +75 deg. The exit bolus simulated is a 1 cm thick (water equivalent) slab located on the beam exit side. Results: On the entry side, significant skin doses at the beam central axis are reported for large positive surface angles and strong magnetic fields. However, over the entry surface angle range of -30 deg. to -60 deg., the entry skin dose is comparable to or less than the zero magnetic field skin dose, regardless of magnetic field strength and field size. On the exit side, moderate to high central axis skin dose increases are expected except at large positive surface angles. For exit bolus of 1 cm thickness, the central axis exit skin dose becomes an almost consistent value regardless of magnetic field strength or exit surface angle. This is due to the almost complete absorption of the ERE electrons by the bolus. Conclusions: There is an ideal entry angle range of -30 deg. to -60 deg. where entry skin dose is comparable to or less than the zero magnetic field skin dose. Other than this, the entry skin dose increases are significant, especially at

  12. Chase the direct impact of rainfall into groundwater in Mt. Fuji from multiple analyses including microbial DNA

    Kato, Kenji; Sugiyama, Ayumi; Nagaosa, Kazuyo; Tsujimura, Maki

    2016-04-01

    A huge amount of groundwater is stored in subsurface environment of Mt. Fuji, the largest volcanic mountain in Japan. Based on the concept of piston flow transport of groundwater an apparent residence time was estimated to ca. 30 years by 36Cl/Cl ratio (Tosaki et al., 2011). However, this number represents an averaged value of the residence time of groundwater which had been mixed before it flushes out. We chased signatures of direct impact of rainfall into groundwater to elucidate the routes of groundwater, employing three different tracers; stable isotopic analysis (delta 18O), chemical analysis (concentration of silica) and microbial DNA analysis. Though chemical analysis of groundwater shows an averaged value of the examined water which was blended by various water with different sources and routes in subsurface environment, microbial DNA analysis may suggest the place where they originated, which may give information of the source and transport routes of the water examined. Throughout the in situ observation of four rainfall events showed that stable oxygen isotopic ratio of spring water and shallow groundwater obtained from 726m a.s.l. where the average recharge height of rainfall was between 1500 and 1800 m became higher than the values before a torrential rainfall, and the concentration of silica decreased after this event when rainfall exceeded 300 mm in precipitation of an event. In addition, the density of Prokaryotes in spring water apparently increased. Those changes did not appear when rainfall did not exceed 100 mm per event. Thus, findings shown above indicated a direct impact of rainfall into shallow groundwater, which appeared within a few weeks of torrential rainfall in the studied geological setting. In addition, increase in the density of Archaea observed at deep groundwater after the torrential rainfall suggested an enlargement of the strength of piston flow transport through the penetration of rainfall into deep groundwater. This finding was

  13. EVALUATION OF PHYTOTOXIC EFFECT OF DELETERIOUS RHIZOBACTERIA ON THE ROOT GROWTH OF AXONOPUS AFFINIS (CHASE AND LENS ESCULENTA (MOENCH

    X.J Pacheco-Hernández

    2015-11-01

    Full Text Available Las malezas ocasionan una gran pérdida en las tierras agrícolas y comúnmente, las medidas de manejo y contención de estas especies se dan con la aplicación de herbicidas, sin embargo; en años recientes se ha presentado un interés en establecer mecanismos de biocontrol seguros, con el empleo de bacterias inhibidoras del crecimiento conocidas como rizobacterias deletéreas (Deleterious rhizobacteria: DRBque se consideran generalmente como no parasíticas, y causan, de manera sutil, efectos deletéreos a través de la producción de metabolitos dañinos a las plantas. El presente trabajo tuvo como objetivo caracterizar la producción de ácido cianhídrico de pseudomonas rizobacterianas de malezas de un cultivo de alfalfa (Medicago sativa L. y evaluar el efecto fitotóxico de éstas sobre el crecimiento radical de plántulas de Axonopus affinis (Chase y Lens esculenta (Moench. De acuerdo con los resultados obtenidos con relación a la evidencia de que los aislados de pseudomonadas son rizobacterias cianogénicas y de su efecto fitotóxico medido sobre las especies vegetales bajo estudio; se sugieren a éstas como posibles agentes de biocontrol con pastos que sean considerados malezas; ya que en general se observó que inhiben su crecimiento radical; sin embargo, un enfoque particular lo tiene la rizobacteria Pseudomonas sp. A52, la cual presentó no solamente actividad como una DRB sino también como una rizobacteria promotora del crecimiento vegetal; lo que la hace más importante de analizar en cuanto a su potencial y espectro de acción; tanto para malezas monocotiledóneas como para dicotiledóneas, recomendable como un posible agente de biocontrol con actividad múltiple.

  14. MPI as high temporal resolution imaging technique for in vivo bolus tracking of Ferucarbotran in mouse model

    Jung, C.; Salamon, J.; Hofmann, M.; Kaul, M. G.; Adam, G.; Ittrich, H.; Knopp, T.

    2016-03-01

    Purpose: The goal of this study was to achieve a real time 3D visualisation of the murine cardiovascular system by intravenously injected superparamagnetic nanoparticles using Magnetic particle imaging (MPI). Material and Methods: MPI scans of FVB mice were performed using a 3D imaging sequence (1T/m gradient strength, 10mT drive-field strength). A dynamic scan with a temporal resolution of 21.5ms per 3D volume acquisition was performed. 50μl ferucarbotran (Resovist®, Bayer Healthcare AG) were injected into the tail vein after baseline MPI measurements. As MPI delivers no anatomic information, MRI scans at a 7T ClinScan (Bruker) were performed using a T2-weighted 2D TSE sequence. The reconstruction of the MPI data was performed on the MPI console (ParaVision 6.0/MPI, Bruker). Image fusion was done using additional image processing software (Imalytics, Philips). The dynamic information was extracted using custom software developed in the Julia programming environment. Results: The combined MRI-MPI measurements were carried out successfully. MPI data clearly demonstrated the passage of the SPIO tracer through the inferior vena cava, the heart and finally the liver. By co-registration with MRI the anatomical regions were identified. Due to the volume frame rate of about 46 volumes per second a signal modulation with the frequency of the heart beat was detectable and a heart beat of 520 beats per minute (bpm) has been assumed. Moreover, the blood flow velocity of approximately 5cm/s in the vena cava has been estimated. Conclusions: The high temporal resolution of MPI allows real-time imaging and bolus tracking of intravenous injected nanoparticles and offers a real time tool to assess blood flow velocity.

  15. Bolus intravenous 0.9% saline, but not 4% albumin or 5% glucose, causes interstitial pulmonary edema in healthy subjects.

    Bihari, Shailesh; Wiersema, Ubbo F; Schembri, David; De Pasquale, Carmine G; Dixon, Dani-Louise; Prakash, Shivesh; Lawrence, Mark D; Bowden, Jeffrey J; Bersten, Andrew D

    2015-10-01

    Rapid intravenous (iv) infusion of 0.9% saline alters respiratory mechanics in healthy subjects. However, the relative cardiovascular and respiratory effects of bolus iv crystalloid vs. colloid are unknown. Six healthy male volunteers were given 30 ml/kg iv 0.9% saline, 4% albumin, and 5% glucose at a rate of 100 ml/min on 3 separate days in a double-blinded, randomized crossover study. Impulse oscillometry, spirometry, lung volumes, diffusing capacity (DLCO), and blood samples were measured before and after fluid administration. Lung ultrasound B-line score (indicating interstitial pulmonary edema) and Doppler echocardiography indices of cardiac preload were measured before, midway, immediately after, and 1 h after fluid administration. Infusion of 0.9% saline increased small airway resistance at 5 Hz (P = 0.04) and lung ultrasound B-line score (P = 0.01) without changes in Doppler echocardiography measures of preload. In contrast, 4% albumin increased DLCO, decreased lung volumes, and increased the Doppler echocardiography mitral E velocity (P = 0.001) and E-to-lateral/septal e' ratio, estimated blood volume, and N-terminal pro B-type natriuretic peptide (P = 0.01) but not lung ultrasound B-line score, consistent with increased pulmonary blood volume without interstitial pulmonary edema. There were no significant changes with 5% glucose. Plasma angiopoietin-2 concentration increased only after 0.9% saline (P = 0.001), suggesting an inflammatory mechanism associated with edema formation. In healthy subjects, 0.9% saline and 4% albumin have differential pulmonary effects not attributable to passive fluid filtration. This may reflect either different effects of these fluids on active signaling in the pulmonary circulation or a protective effect of albumin. PMID:26228998

  16. Approximate semianalytical solution for tracer injection tests in a confined aquifer with a radially converging flow field and finite volume of tracer and chase fluid

    An approximate analytical solution describing the movement of a conservative tracer of finite volume in a radially converging flow field is proposed. The solution is divided into two phases: injection and transport. During the injection phase, an injection of chase fluid immediately following the tracer is allowed. Hydrodynamic dispersion effects are assumed to be negligible during this phase. The geometry of the tracer plume is determined by a particle-tracking technique. During the plume transport phase, the tracer plume is approximated by a series of contiguous pulses. An approximate analytical solution for each pulse has been derived through linearization of the transport equation. The approximate solution has been verified by comparison with numerical solutions. The distribution of tracer in space and time is obtained by summing the contributions from all the pulses. Four geometrical parameters governing the geometry of the tracer plume immediately after injection are presented and discussed. The solution shows that the geometry of the initial tracer plume has an effect of the breakthrough curves. The volume of tracer and chase fluid has to be taken into account in tracer test design and data analysis. Limitations of the proposed solution are also discussed

  17. Chasing Graduate Jobs?

    Mosca, Irene; Wright, Robert

    2011-01-01

    This paper examines empirically the relationship between under-employment and migration amongst five cohorts of graduates of Scottish higher education institutions with micro-data collected by the Higher Education Statistical Agency. The data indicate that there is a strong positive relationship between migration and graduate employment - those graduates who move after graduation from Scotland to the rest of the UK or abroad have a much higher rate of graduate employment. Versions of probit r...

  18. Chasing the radium rainbow

    Soon after the discovery of radium, its potential for curing cancer was realized. This important use, along with industrial applications, generated a demand which was met by the establishment of a radium mining and extraction industry. The first large supplier was the United States, later completely supplanted by Belgium. The Canadian radium industry arose with Eldorado Gold Mines Ltd. mining pitchblende ore near Great Bear Lake and extracting radium at Port Hope. The venture foundered financially, but Eldorado's technical and marketing expertise provided the foundation for later successes in fields in which Canada is now a world leader

  19. Chasing the holy grail

    Jenvey, N.

    2001-05-01

    Sufficient port capacity for South Africa's coal exporters remains a dream, despite the promises of recent years. The only firm plans for Richards Bay Terminal seem to be an expansion of capacity by 10 mt to 82 mtpa. An environmental impact assessment is currently being made. Mozambique's port of Maputo however does seem to be progressing well. Phase two of a construction development which will double production capacity starts later this year. 4 photos.

  20. Chasing Unachievable Outcomes

    Pangrazi, Robert P.

    2010-01-01

    Today, teachers complain about the lack of physical education time and the lack of physical education programming. In addition, a great deal of time is spent advocating the relationship between "healthy mind-healthy body." Today's drive to show a relationship between physical fitness/activity and academic achievement is really not different than…

  1. Chasing the Hofstadter Butterfly

    Satija, Indu

    2014-03-01

    The experimental observation of the Hofstadter butterfly, the fascinating quantum fractal that also encodes the Chern numbers associated with quantum Hall state, continues to remain a challenging task. It may be possible to observe the fine structure of the butterfly, consisting of small gaps of the spectrum characterized by topological invariants greater than unity, with a resolution matching that of the Chern-1 gaps that form the skeleton of the butterfly. The tiny gaps of the butterfly emanating from a rational flux p / q are found to be associated with infinity of possible solutions (of Diophantine equation)for the rational flux. Not supported by the simple square lattice nearest-neighbor hopping model of the Hofstadter system, these solutions are found to be hiding in neighborhood of these fluxes. By perturbing this simple system, it is possible to ``amplify'' these small gaps corresponding to higher Chern states where they replace the Chern 1 gap of the Hofstadter butterfly. In other words, by tuning a parameter, it is possible to induce topological quantum phase transitions where the finer gaps become the new major gaps that dominate the spectrum. This may provide a possible pathway to see the topological landscape of the Hofstadter butterfly fractal in its entirety.

  2. Chasing Captain Hook

    2009-01-01

    Somalia has come into the international media spotlight because of the high-profile pirate attacks off its coast. But piracy is only part of the Horn of Africa country’s ordeal. Somalia has been embroiled in armed conflicts between feuding warlords since 1991, without a central government that can put the country under effective control. In an interview with Beijing Review reporter Yan Wei, Somalia’s Ambassador to China Mohammed Awil called on the international community to help his war-torn country fight piracy, stop illegal fishing and waste dumping in Somali waters and achieve peace and reconciliation. The ambassador also gave positive evaluation to China’s naval presence on Somali waters. Excerpts of the interview follow

  3. Adaptation Laboratory

    Huq, Saleemul

    2011-11-15

    Efforts to help the world's poor will face crises in coming decades as climate change radically alters conditions. Action Research for Community Adapation in Bangladesh (ARCAB) is an action-research programme on responding to climate change impacts through community-based adaptation. Set in Bangladesh at 20 sites that are vulnerable to floods, droughts, cyclones and sea level rise, ARCAB will follow impacts and adaptation as they evolve over half a century or more. National and international 'research partners', collaborating with ten NGO 'action partners' with global reach, seek knowledge and solutions applicable worldwide. After a year setting up ARCAB, we share lessons on the programme's design and move into our first research cycle.

  4. Hedonic "adaptation"

    Paul Rozin

    2008-02-01

    Full Text Available People live in a world in which they are surrounded by potential disgust elicitors such as ``used'' chairs, air, silverware, and money as well as excretory activities. People function in this world by ignoring most of these, by active avoidance, reframing, or adaptation. The issue is particularly striking for professions, such as morticians, surgeons, or sanitation workers, in which there is frequent contact with major disgust elicitors. In this study, we study the ``adaptation'' process to dead bodies as disgust elicitors, by measuring specific types of disgust sensitivity in medical students before and after they have spent a few months dissecting a cadaver. Using the Disgust Scale, we find a significant reduction in disgust responses to death and body envelope violation elicitors, but no significant change in any other specific type of disgust. There is a clear reduction in discomfort at touching a cold dead body, but not in touching a human body which is still warm after death.

  5. Adaptive ethnography

    Berth, Mette

    2005-01-01

    This paper focuses on the use of an adaptive ethnography when studying such phenomena as young people's use of mobile media in a learning perspective. Mobile media such as PDAs and mobile phones have a number of affordances which make them potential tools for learning. However, before we begin to...... design and develop educational materials for mobile media platforms we must first understand everyday use and behaviour with a medium such as a mobile phone. The paper outlines the research design for a PhD project on mobile learning which focuses on mobile phones as a way to bridge the gap between...... formal and informal learning contexts. The paper also proposes several adaptive methodological techniques for studying young people's interaction with mobiles....

  6. Adaptable positioner

    This paper describes the circuits and programs in assembly language, developed to control the two DC motors that give mobility to a mechanical arm with two degrees of freedom. As a whole, the system is based in a adaptable regulator designed around a 8 bit microprocessor that, starting from a mode of regulation based in the successive approximation method, evolve to another mode through which, only one approximation is sufficient to get the right position of each motor. (Author) 22 fig. 6 ref

  7. Adaptive positioner

    This paper describes the circuits and programs in assembly language, developed to control the two DC motors that give mobility to a mechanical arm with two degrees of freedom. As a whole, the system is based in a adaptable regulator designed around a 8 bit microprocessor that, starting from a mode of regulation based in the successive approximation method, evolve to another mode through which, only one approximation is sufficient to get the right position of each motor. (Author) 6 refs

  8. Adaptive noise

    Viney, Mark; Reece, Sarah E.

    2013-01-01

    In biology, noise implies error and disorder and is therefore something which organisms may seek to minimize and mitigate against. We argue that such noise can be adaptive. Recent studies have shown that gene expression can be noisy, noise can be genetically controlled, genes and gene networks vary in how noisy they are and noise generates phenotypic differences among genetically identical cells. Such phenotypic differences can have fitness benefits, suggesting that evolution can shape noise ...

  9. Gastrostomy feeding tube - bolus

    ... a gastrostomy tube. Delmar’s Fundamental and Advanced Nursing Skills . 2nd Ed. Albany, NY: Delmar Thomson Learning; 2003: 742-749. Simmons, Remmington R.The percutaneous endoscopic gastrostomy tube: a nurse's guide to PEG tubes. Medsurg Nurs . 2013 Mar- ...

  10. Optimal scan techniques for dynamic gadolinium-enhanced MR imaging of the liver. Usefulness of test injection method and automated bolus tracking technique

    This study was performed to determine optimal scan techniques and important factors in dynamic gadolinium-enhanced MR imaging of the liver. Comparing the influence of test bolus injection to that of the automatic trigger was done in the same cases. One hundred patients were enrolled in the whole liver dynamic study using a 1.5 T MR system. MR imaging using a power injector was performed in 85 cases, while manual injection was performed in the other 15 cases. Fast spoiled GRASS (FSPGR) or enhanced 3D fast gradient echo (efgre3d) pulse sequence was used for the study. MR SmartPrep, which is a computer assisted bolus tracking technique, was performed in 37 of the 57 cases with efgre3d. Both test bolus and MR SmartPrep were used in 10 of the 57 cases. Hepatic arterial phase images were designated to 3 grades of scan timing. Optimal timing was determined when a faint depiction of portal vein in addition to a description of second branches of the hepatic artery were present. The best timing was found in efgre3d 3 ml/s with a SmartPrep in which the acquisition delay time was 10 s. The mean delay time from the initiation of contrast agent administration to the beginning of arterial phase scanning was 17.0±4.71 s (mean±SD, range 10-29 s). Although similar effects might be achieved when the test injection method is used, it requires complicated steps. These results indicate that we can perform optimal timing for the hepatic arterial phase of dynamic MR imaging. We can also set the delay time for individual cases with the power injector. (author)

  11. Meta-analysis of insulin aspart versus regular human insulin used in a basal–bolus regimen for the treatment of diabetes mellitus

    Heller, Simon; Bode, Bruce; Kozlovski, Plamen; Svendsen, Anne Louise

    2013-01-01

    Background: The objective of the current study was to compare the efficacy of two different insulin formulations, insulin aspart (IAsp) and regular human insulin (RHI), for prandial insulin coverage with neutral protamine Hagedorn (NPH) insulin as basal insulin using a meta-analysis approach. The primary endpoint was change in A1c over time. Secondary endpoints included incidence of hypoglycemia and postprandial glycemic control. Methods Clinical trials (Type 1 and Type 2 diabetes) complying with Good Clinical Practice, and with individual patient data, were included in the meta-analysis. Trials were randomized, consisting of (at least) two treatment arms and had a minimum duration of 12 weeks. Estimates were calculated using fixed-effects and random-effects models. Heterogeneity was assessed for each analysis. The effect of baseline parameters on A1c was analyzed in extended simultaneous models. Results The mean difference in A1c was 0.1% (95% confidence interval [CI] [−0.15; −0.04], P < 0.001) in favor of IAsp. Higher accumulated dose of IAsp, higher age and increased rates of hypoglycemia were associated with improved A1c outcome. Fasting plasma glucose was not significantly different between regimens. Postprandial glucose was significantly lower after treatment with IAsp compared with RHI, but the analysis did present a significant level of heterogeneity (P < 0.001). The overall rate of hypoglycemia was the same with both regimens, but nocturnal hypoglycemia was significantly lower with IAsp. Conclusions A basal–bolus regimen with IAsp as bolus insulin provided minimal, but statistically significant, improvement in overall glycemic control with a lower rate of nocturnal hypoglycemic episodes, compared with a corresponding regimen with bolus RHI. PMID:23586846

  12. Comparison of bolus and continuous infusion of esmolol on hemodynamic response to laryngoscopy, endotracheal intubation and sternotomy in coronary artery bypass graft

    Esra Mercanooglu Efe

    2014-07-01

    Full Text Available BACKGROUND AND OBJECTIVE: The aim of this randomized, prospective and double blinded study is to investigate effects of different esmolol use on hemodynamic response of laryngoscopy, endotracheal intubation and sternotomy in coronary artery bypass graft surgery. METHODS: After approval of local ethics committee and patients' written informed consent, 45 patients were randomized into three groups equally. In Infusion Group; from 10 min before intubation up to 5th minute after sternotomy, 0.5 mg/kg/min esmolol infusion, in Bolus Group; 2 min before intubation and sternotomy 1.5 mg/kg esmolol IV bolus and in Control Group; %0.9 NaCl was administered. All demographic parameters were recorded. Heart rate and blood pressure were recorded before infusion up to anesthesia induction in every minute, during endotracheal intubation, every minute for 10 minutes after endotracheal intubation and before, during and after sternotomy at first and fifth minutes. RESULTS: While area under curve (AUC (SAP × time was being found more in Group B and C than Group I, AUC (SAP × T int and T st and AUC (SAP × T2 was found more in Group B and C than Group I (p < 0.05. Moreover AUC (HR × T st was found less in Group B than Group C but no significant difference was found between Group B and Group I. CONCLUSION: This study highlights that esmolol infusion is more effective than esmolol bolus administration on controlling systolic arterial pressure during endotracheal intubation and sternotomy in CABG surgery.

  13. Quantitative Determination of Ursolic Acid in Dashanzha Bolus by Spectrophotometry%分光光度法测定大山楂丸中熊果酸含量

    李莹; 陈新梅

    2013-01-01

    目的 建立可见分光光度法测定自制大山楂丸中熊果酸含量的方法.方法 采用可见分光光度法,用5%香草醛-冰醋酸、高氯酸显色,以熊果酸标准品为对照,波长545 nm处测定自制大山楂丸中熊果酸的含量.结果 熊果酸在12~60 μg/mL浓度范围内具有良好的吸光度与浓度的线性关系(r=0.9995);样品平均回收率为98.47%,RSD=1.57%.精密度、重现性好;对照品和样品溶液在1h内稳定.结论 此法操作方便、简练、高效,可用于大山楂丸中熊果酸含量的测定.%Objective To establish a method for the determination of ursolic acid in Dashanzha bolus by spectrophotometry.Methods With spectrophotometry,5 % vanillin-acetic acid,perchloric acid for color,the ursolic acid standard control,ursolic acid content of homemade Dashanzha bolus was determined at the wavelength of 545 nm.Results The method can accurately determined the content of malol in Dashanzha bolus.ursolic acid at the concentration of 12~60 μg/mL had a good linear relationship between the absorbance and the concentration (r=0.9995).Sample average recovery rate was 98.47 %,RSD=1.57 %.Standard and sample solution were stable within 1 h.Conclusion The method has the advantages of convenient operation,simplicity,high efficiency,and can be used for determination of ursolic acid content in Dashanzha bolus.

  14. A randomized double-blind placebo-controlled trial to evaluate the value of a single bolus intravenous alfentanil in CT colonography

    Boellaard Thierry N

    2011-11-01

    Full Text Available Abstract Background Although CT colonography is a less invasive alternative for colonoscopy for the detection of colorectal polyps and cancer, procedural pain is common. In several studies, CT colonography pain and burden is higher than in colonoscopy. Apart from discomfort, anxiety and its related stress-induced peri- procedural side effects, this may influence the adherence for CT colonography as a possible screening tool for colorectal cancer. We hypothesize that a single bolus intravenous alfentanil will give a clinically relevant reduction in maximum pain defined as at least 1.3 point reduction on an 11-point numeric rating scale (NRS. Methods/Design A randomized double-blind placebo-controlled trial in which patients scheduled for elective CT colonography in a single tertiary centre are eligible for inclusion. The first 90 consenting patient will be block-randomized to either the alfentanil group or the placebo group. Before bowel insufflation, the alfentanil group receives a single bolus intravenous alfentanil 7.5 μg/kg dissolved in 0.9% NaCl, while the placebo group receives an intravenous bolus injection of pure 0.9% NaCl. For both groups an equal amount of fluid per kilogram (75 μL/kg is injected. The primary outcome is the difference in maximum pain on an 11-point NRS. Secondary outcomes include: pain and burden of different CT colonography aspects, side effects, procedural time and recovery time. For the primary outcome an independent samples t-test is performed and a P value Discussion This study will provide evidence whether a single bolus intravenous alfentanil gives a clinically relevant reduction in maximum pain during CT colonography. Trial registration Netherlands Trial Register (NTR: NTR2902 This trial will be conducted in accordance with the protocol and in compliance with the moral, ethical, and scientific principles governing clinical research as set out in the Declaration of Helsinki (1989 and Good Clinical Practice

  15. Effects of maintenance of propofol-ketamine anesthesia with repeat bolus and constant rate infusion of propofol on physiological, biochemical, anesthetic and analgesic indices in dogs

    Njoku Uchechukwu Njoku

    2015-01-01

    The research work was aimed at investigating physiological, biochemical, analgesic and anesthetic indices of dogs anesthetized with propofol-ketamine and maintained with repeat bolus and constant infusions of propofol. Eight dogs, assigned to two groups (n=4), were used in this study. All dogs were pre-medicated with atropine (at 0.03 mg/kg bwt) and xylazine (at 2 mg/kg bwt). Anesthesia was induced by a concurrent administration of propofol (at 4 mg/kg bwt) and ketamine (at 2.5 mg/kg bwt). Ma...

  16. Reducing the radiation dose to the eye lens region during CT brain examination: the potential beneficial effect of the combined use of bolus and a bismuth shield

    Objective: Computed Tomography (CT) is the leading contributor to medical exposure to ionizing radiation. Although the use of CT brain scans for patients with head injuries and convulsions has shown a tremendous growth, it has raised substantial concerns in the general public because of the risk of radiation-induced cataracts: the current available strategies to reduce the radiation dose to the eye lens region are limited. Therefore, the present research project was initiated with the aim of evaluating the potential benefit of the combined use of bolus and a bismuth shield on reducing the radiation dose to the eye lens region during CT brain examination. Materials and methods: We conducted a series of phantom studies to measure the entrance surface dose (ESD) that is delivered to the eye lens region during CT brain examination under the effect of different scanning and shielding setups. Results: Our results indicated, during CT brain examination: (1) a drastic reduction of 92.5% in the ESD to the eye lens region was found when the CT gantry was tilted from 0 deg. (overall ESD = 30.7 mGy) to 30 deg. cranially (overall ESD = 2.4 mGy), and (2) when the CT gantry was positioned at 0 deg. (the common practice in the clinical setting), the setups with the application of a) a bismuth shield, b) a bismuth shield with a face shield (air gap), c) a bismuth shield with bolus, and d) a bismuth shield with bolus and an air gap can result in an acceptable level of image quality with a smaller overall ESD delivered to the eye lens region (overall ESD = 23.2 mGy, 24 mGy, 21 mGy and 19.9 mGy, respectively) than the setup without the bismuth shield applied (overall ESD = 30.7 mGy). Conclusion: When the primary beam scanning through the eye lens region is unavoidable during CT brain examination, the combined use of a bismuth shield with bolus and a face shield is an easy-to-use and inexpensive shielding setup to reduce the radiation dose delivered to the eye lens region while

  17. Treatment planning at the neutron facility of the hospital of the University of Pennsylvania and the hospital of the Fox Chase Cancer Center in Philadelphia

    In the paper the method is demonstrated being used at the Fox Chase Cancer Center Hospital Neutron Facility for obtaining accurate computer generated isodose distributions. Their determination is based on the Cunningham code, allowing separate calculation of primary and scatter dose components. Tissue inhomogeneity corrections for the neutron beam will be determined from measurements of the tissue air ratio in bone equivalent solution and granulated tissue equivalent plastic used to simulate lung tissue. The correction in the dose when the neutron beam enters subcutaneous fat or brain tissue, which have higher hydrogen concentrations than muscle, will be obtained from measurements of tissue-air ratios in liquids (hydrocarbons) with various hydrogen concentrations. Finally, the treatment planning at the neutron facility will take advantage of the three-dimensional perspectives of the internal anatomy of the patient that can be obtained from multi-sectional computer axial tomographic scans. Superimposed on these scans will be the calculated three-dimensional dose distributions. (orig.)

  18. Black carbon, particle number concentration and nitrogen oxide emission factors of random in-use vehicles measured with the on-road chasing method

    I. Ježek

    2015-06-01

    Full Text Available The chasing method was used in an on-road measurement campaign, and emission factors (EF of black carbon (BC, particle number (PN and nitrogen oxides (NOx were determined for 139 individual vehicles of different types encountered on the roads. The aggregated results provide EFs for BC, NOx and PN for three vehicle categories: goods vehicles, gasoline and diesel passenger cars. This is the first on-road measurement study where BC EFs of numerous individual diesel cars were determined in real-world driving conditions. We found good agreement between EFs of goods vehicles determined in this campaign and the results of previous studies that used either chasing or remote sensing measurement techniques. The composition of the sampled car fleet determined from the national vehicle registry information is reflective of Eurostat statistical data on the Slovenian and European vehicle fleet. The median BC EF of diesel and gasoline cars that were in use for less than 5 years, decreased by 60 and 47% from those in use for 5–10 years, respectively, the median NOx and PN EFs, of goods vehicles that were in use for less than five years, decreased from those in use for 5–10 years by 52 and 67%, respectively. The influence of engine maximum power of the measured EFs showed an increase in NOx EF from least to more powerful vehicles with diesel engines. Finally a disproportionate contribution of high emitters to the total emissions of the measured fleet was found; the top 25% of emitting diesel cars contributed 63, 47 and 61% of BC, NOx and PN emissions respectively. With the combination of relatively simple on-road measurements with sophisticated post processing individual vehicles EF can be determined and useful information about the fleet emissions can be obtained by exactly representing vehicles which contribute disproportionally to vehicle fleet emissions; and monitor how the numerous emission reduction approaches are reflected in on-road driving

  19. Adaptive management

    Rist, Lucy; Campbell, Bruce Morgan; Frost, Peter

    2013-01-01

    in scientific articles, policy documents and management plans, but both understanding and application of the concept is mixed. This paper reviews recent literature from conservation and natural resource management journals to assess diversity in how the term is used, highlight ambiguities and consider how......Adaptive management (AM) emerged in the literature in the mid-1970s in response both to a realization of the extent of uncertainty involved in management, and a frustration with attempts to use modelling to integrate knowledge and make predictions. The term has since become increasingly widely used...... the concept might be further assessed. AM is currently being used to describe many different management contexts, scales and locations. Few authors define the term explicitly or describe how it offers a means to improve management outcomes in their specific management context. Many do not adhere to the idea...

  20. Development and Clinical Implementation of a Universal Bolus to Maintain Spot Size During Delivery of Base of Skull Pencil Beam Scanning Proton Therapy

    Both, Stefan, E-mail: Stefan.Both@uphs.upenn.edu [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States); Shen, Jiajian [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States); Department of Radiation Oncology, Mayo Clinic, Phoenix, Arizona (United States); Kirk, Maura; Lin, Liyong; Tang, Shikui; Alonso-Basanta, Michelle; Lustig, Robert; Lin, Haibo; Deville, Curtiland; Hill-Kayser, Christine; Tochner, Zelig; McDonough, James [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States)

    2014-09-01

    Purpose: To report on a universal bolus (UB) designed to replace the range shifter (RS); the UB allows the treatment of shallow tumors while keeping the pencil beam scanning (PBS) spot size small. Methods and Materials: Ten patients with brain cancers treated from 2010 to 2011 were planned using the PBS technique with bolus and the RS. In-air spot sizes of the pencil beam were measured and compared for 4 conditions (open field, with RS, and with UB at 2- and 8-cm air gap) in isocentric geometry. The UB was applied in our clinic to treat brain tumors, and the plans with UB were compared with the plans with RS. Results: A UB of 5.5 cm water equivalent thickness was found to meet the needs of the majority of patients. By using the UB, the PBS spot sizes are similar with the open beam (P>.1). The heterogeneity index was found to be approximately 10% lower for the UB plans than for the RS plans. The coverage for plans with UB is more conformal than for plans with RS; the largest increase in sparing is usually for peripheral organs at risk. Conclusions: The integrity of the physical properties of the PBS beam can be maintained using a UB that allows for highly conformal PBS treatment design, even in a simple geometry of the fixed beam line when noncoplanar beams are used.

  1. Development and Clinical Implementation of a Universal Bolus to Maintain Spot Size During Delivery of Base of Skull Pencil Beam Scanning Proton Therapy

    Purpose: To report on a universal bolus (UB) designed to replace the range shifter (RS); the UB allows the treatment of shallow tumors while keeping the pencil beam scanning (PBS) spot size small. Methods and Materials: Ten patients with brain cancers treated from 2010 to 2011 were planned using the PBS technique with bolus and the RS. In-air spot sizes of the pencil beam were measured and compared for 4 conditions (open field, with RS, and with UB at 2- and 8-cm air gap) in isocentric geometry. The UB was applied in our clinic to treat brain tumors, and the plans with UB were compared with the plans with RS. Results: A UB of 5.5 cm water equivalent thickness was found to meet the needs of the majority of patients. By using the UB, the PBS spot sizes are similar with the open beam (P>.1). The heterogeneity index was found to be approximately 10% lower for the UB plans than for the RS plans. The coverage for plans with UB is more conformal than for plans with RS; the largest increase in sparing is usually for peripheral organs at risk. Conclusions: The integrity of the physical properties of the PBS beam can be maintained using a UB that allows for highly conformal PBS treatment design, even in a simple geometry of the fixed beam line when noncoplanar beams are used

  2. Usefulness of the Bolus-Tracking Baseline Scan for the Diagnosis of Hepatic Steatosis in Abdominal Computed Tomography: A Feasibility Study

    Nonalcoholic fatty liver disease (NAFLD) is a common pathology in western societies. Unenhanced computed tomography (CT) of the liver is a valuable tool in determining the presence of steatosis hepatis, but in most departments standard CT protocols of abdomen often do not include unenhanced scans anymore. In a small series of 22 patients the liver density was measured in the acquired low-dose baseline scan for bolus tracking and was compared to the measurement in a regular unenhanced CT scan of the upper abdomen. The mean difference between the unenhanced CT scan and the low-dose baseline scan was 3.4 HU (range 0.2–8.6 HU); the difference between these two scans was 5 HU or smaller in 82% of the patients. There was a significant difference between the two used CT scanners; this has to be kept in mind before implementing this approach into daily practice. All but one patient with fatty liver disease on unenhanced CT were diagnosed using the baseline scan. The baseline scan for bolus tracking may be useful for the diagnosis or in the followup of fatty liver disease

  3. Solving delay differential equations in S-ADAPT by method of steps.

    Bauer, Robert J; Mo, Gary; Krzyzanski, Wojciech

    2013-09-01

    S-ADAPT is a version of the ADAPT program that contains additional simulation and optimization abilities such as parametric population analysis. S-ADAPT utilizes LSODA to solve ordinary differential equations (ODEs), an algorithm designed for large dimension non-stiff and stiff problems. However, S-ADAPT does not have a solver for delay differential equations (DDEs). Our objective was to implement in S-ADAPT a DDE solver using the methods of steps. The method of steps allows one to solve virtually any DDE system by transforming it to an ODE system. The solver was validated for scalar linear DDEs with one delay and bolus and infusion inputs for which explicit analytic solutions were derived. Solutions of nonlinear DDE problems coded in S-ADAPT were validated by comparing them with ones obtained by the MATLAB DDE solver dde23. The estimation of parameters was tested on the MATLB simulated population pharmacodynamics data. The comparison of S-ADAPT generated solutions for DDE problems with the explicit solutions as well as MATLAB produced solutions which agreed to at least 7 significant digits. The population parameter estimates from using importance sampling expectation-maximization in S-ADAPT agreed with ones used to generate the data. PMID:23810514

  4. Switching from Twice-Daily Basal Insulin Injections to Once-Daily Insulin Degludec Injection for Basal-Bolus Insulin Regimen in Japanese Patients with Type 1 Diabetes: A Pilot Study

    Yuka Tosaka; Akio Kanazawa; Fuki Ikeda; Mayu Iida; Junko Sato; Kazuhisa Matsumoto; Toyoyoshi Uchida; Yoshifumi Tamura; Takeshi Ogihara; Tomoya Mita; Tomoaki Shimizu; Hiromasa Goto; Chie Ohmura; Yoshio Fujitani; Hirotaka Watada

    2015-01-01

    The aim of this study was to investigate the efficacy of insulin degludec used for basal-bolus insulin regimen after switching from twice-daily basal insulin in Japanese patients with type 1 diabetes mellitus. The subjects were 22 type 1 diabetes patients treated with basal-bolus insulin regimen with twice-daily basal insulin. Basal insulin was switched to once-daily injection of insulin degludec with 10% dose reduction. HbA1c and fasting plasma glucose (FPG) were measured before and 12 weeks...

  5. Radiation treatment for the right naris in a pediatric anesthesia patient using an adaptive oral airway technique

    Radiation therapy for pediatric patients often includes the use of intravenous anesthesia with supplemental oxygen delivered via the nasal cannula. Here, we describe the use of an adaptive anesthesia technique for electron irradiation of the right naris in a preschool-aged patient treated under anesthesia. The need for an intranasal bolus plug precluded the use of standard oxygen supplementation. This novel technique required the multidisciplinary expertise of anesthesiologists, radiation therapists, medical dosimetrists, medical physicists, and radiation oncologists to ensure a safe and reproducible treatment course

  6. Radiation treatment for the right naris in a pediatric anesthesia patient using an adaptive oral airway technique

    Sponseller, Patricia, E-mail: sponselp@uw.edu; Pelly, Nicole; Trister, Andrew; Ford, Eric; Ermoian, Ralph

    2015-10-01

    Radiation therapy for pediatric patients often includes the use of intravenous anesthesia with supplemental oxygen delivered via the nasal cannula. Here, we describe the use of an adaptive anesthesia technique for electron irradiation of the right naris in a preschool-aged patient treated under anesthesia. The need for an intranasal bolus plug precluded the use of standard oxygen supplementation. This novel technique required the multidisciplinary expertise of anesthesiologists, radiation therapists, medical dosimetrists, medical physicists, and radiation oncologists to ensure a safe and reproducible treatment course.

  7. Effects of orally applied butyrate bolus on histone acetylation and cytochrome P450 enzyme activity in the liver of chicken – a randomized controlled trial

    Mátis Gábor

    2013-01-01

    Full Text Available Abstract Background Butyrate is known as histone deacetylase inhibitor, inducing histone hyperacetylation in vitro and playing a predominant role in the epigenetic regulation of gene expression and cell function. We hypothesized that butyrate, endogenously produced by intestinal microbial fermentation or applied as a nutritional supplement, might cause similar in vivo modifications in the chromatin structure of the hepatocytes, influencing the expression of certain genes and therefore modifying the activity of hepatic microsomal drug-metabolizing cytochrome P450 (CYP enzymes. Methods An animal study was carried out in chicken as a model to investigate the molecular mechanisms of butyrate’s epigenetic actions in the liver. Broiler chicks in the early post-hatch period were treated once daily with orally administered bolus of butyrate following overnight starvation with two different doses (0.25 or 1.25 g/kg body weight per day for five days. After slaughtering, cell nucleus and microsomal fractions were separated by differential centrifugation from the livers. Histones were isolated from cell nuclei and acetylation of hepatic core histones was screened by western blotting. The activity of CYP2H and CYP3A37, enzymes involved in biotransformation in chicken, was detected by aminopyrine N-demethylation and aniline-hydroxylation assays from the microsomal suspensions. Results Orally added butyrate, applied in bolus, had a remarkable impact on nucleosome structure of hepatocytes: independently of the dose, butyrate caused hyperacetylation of histone H2A, but no changes were monitored in the acetylation state of H2B. Intensive hyperacetylation of H3 was induced by the higher administered dose, while the lower dose tended to increase acetylation ratio of H4. In spite of the observed modification in histone acetylation, no significant changes were observed in the hepatic microsomal CYP2H and CYP3A37 activity. Conclusion Orally added butyrate in bolus

  8. Use Case Design for AdaptIVe

    Wolter, Stefan; Kelsch, Johann

    2014-01-01

    AdaptIVe is a large scale European project on vehicle automation and the pertaining human-machine interaction. The use case design process is a crucial part of the system design process and a part of the human-vehicle integration subproject. This paper explains the methodology for describing use cases in AdaptIVe. They are primarily based on sequence diagrams with main and alternative flows.

  9. Adaptively robust filtering with classified adaptive factors

    CUI Xianqiang; YANG Yuanxi

    2006-01-01

    The key problems in applying the adaptively robust filtering to navigation are to establish an equivalent weight matrix for the measurements and a suitable adaptive factor for balancing the contributions of the measurements and the predicted state information to the state parameter estimates. In this paper, an adaptively robust filtering with classified adaptive factors was proposed, based on the principles of the adaptively robust filtering and bi-factor robust estimation for correlated observations. According to the constant velocity model of Kalman filtering, the state parameter vector was divided into two groups, namely position and velocity. The estimator of the adaptively robust filtering with classified adaptive factors was derived, and the calculation expressions of the classified adaptive factors were presented. Test results show that the adaptively robust filtering with classified adaptive factors is not only robust in controlling the measurement outliers and the kinematic state disturbing but also reasonable in balancing the contributions of the predicted position and velocity, respectively, and its filtering accuracy is superior to the adaptively robust filter with single adaptive factor based on the discrepancy of the predicted position or the predicted velocity.

  10. PK/PD modelling of glucose-insulin-glucagon dynamics in healthy dogs after a subcutaneous bolus administration of native glucagon or a novel glucagon analogue

    Wendt, Sabrina Lyngbye; Møller, Jan Kloppenborg; Boye Knudsen, Carsten;

    Objective We aim to develop a simulation model of the complex glucose-insulin-glucagon dynamics based on physiology and data. Furthermore, we compare pharmacokinetic (PK) and pharmacodynamic (PD) characteristics of marketed reconstituted glucagon with a stable liquid glucagon analogue invented by...... received two subcutaneous (SC) bolus injections of low and high doses of glucagon and ZP-GA-1 (20 and 120 nmol/kg). Results We report posterior probability distributions and correlations for all identifiable model parameters. Based on visual inspection and residual analysis, the PD model described data...... parameters given priors reported in the literature. We used profile likelihood analysis to investigate parameter identifiability and reduce the number of model variables. We estimated model parameters in pre-clinical data from one cross-over study with a total of 20 experiments in five dogs. The dogs...

  11. Reproducibility of 5-HT2A receptor measurements and sample size estimations with [18F]altanserin PET using a bolus/infusion approach

    Haugbøl, Steven; Pinborg, Lars H; Arfan, Haroon M; Frøkjaer, Vibe M; Madsen, Jacob; Dyrby, Tim; Svarer, Claus; Knudsen, Gitte M

    2006-01-01

    PURPOSE: To determine the reproducibility of measurements of brain 5-HT2A receptors with an [18F]altanserin PET bolus/infusion approach. Further, to estimate the sample size needed to detect regional differences between two groups and, finally, to evaluate how partial volume correction affects...... reproducibility and the required sample size. METHODS: For assessment of the variability, six subjects were investigated with [18F]altanserin PET twice, at an interval of less than 2 weeks. The sample size required to detect a 20% difference was estimated from [18F]altanserin PET studies in 84 healthy subjects......% (range 5-12%), whereas in regions with a low receptor density, BP1 reproducibility was lower, with a median difference of 17% (range 11-39%). Partial volume correction reduced the variability in the sample considerably. The sample size required to detect a 20% difference in brain regions with high...

  12. ESTUDIO DEL EFECTO DE LA APLICACIÓN DE BIOFERTILIZANTES SOBRE ALGUNAS VARIABLES DE CRECIMIENTO Y RENDIMIENTO EN Gerbera jamesonii cv. Bolus

    María R. Soroa

    2003-01-01

    Full Text Available El trabajo experimental se desarrolló con el objetivo de estudiar el efecto de la aplicación de biofertilizantes a partir de hongos micorrizógenos arbusculares (HMA y rizobacterias promotoras del crecimiento vegetal (RPCV, sobre algunas variables de crecimiento y rendimiento en Gerbera jamesonii cv. Bolus, especie que se emplea como flor cortada y planta florecida en macetas. La experiencia mostró que se produjeron importantes incrementos al emplear estos microorganismos en el cultivo en estudio, siendo el tratamiento inoculado con Glomus fasciculatum el que mejor se comportó de manera integral y destacándose al analizar las variables: diámetro de las flores (27.9 % de incremento, rendimiento e inicio de la floración (50 días antes con respecto al tratamiento control.

  13. Black carbon, particle number concentration and nitrogen oxide emission factors of random in-use vehicles measured with the on-road chasing method

    Ježek, I.; Katrašnik, T.; Westerdahl, D.; Močnik, G.

    2015-10-01

    The chasing method was used in an on-road measurement campaign, and emission factors (EF) of black carbon (BC), particle number (PN) and nitrogen oxides (NOx) were determined for 139 individual vehicles of different types encountered on the roads. The aggregated results provide EFs for BC, NOx and PN for three vehicle categories: goods vehicles, gasoline and diesel passenger cars. This is the first on-road measurement study where BC EFs of numerous individual diesel cars were determined in real-world driving conditions. We found good agreement between EFs of goods vehicles determined in this campaign and the results of previous studies that used either chasing or remote-sensing measurement techniques. The composition of the sampled car fleet determined from the national vehicle registry information is reflective of Eurostat statistical data on the Slovenian and European vehicle fleet. The median BC EF of diesel and gasoline cars that were in use for less than 5 years decreased by 60 and 47 % from those in use for 5-10 years, respectively; the median NOx and PN EFs of goods vehicles that were in use for less than 5 years decreased from those in use for 5-10 years by 52 and 67 %, respectively. Surprisingly, we found an increase of BC EFs in the newer goods vehicle fleet compared to the 5-10-year old one. The influence of engine maximum power of the measured EFs showed an increase in NOx EF from least to more powerful vehicles with diesel engines. Finally, a disproportionate contribution of high emitters to the total emissions of the measured fleet was found; the top 25 % of emitting diesel cars contributed 63, 47 and 61 % of BC, NOx and PN emissions respectively. With the combination of relatively simple on-road measurements and sophisticated post processing, individual vehicle EF can be determined and useful information about the fleet emissions can be obtained by exactly representing vehicles which contribute disproportionally to vehicle fleet emissions; and

  14. Metastasizing, Luciferase Transduced MAT-Lu Rat Prostate Cancer Models: Follow up of Bolus and Metronomic Therapy with Doxorubicin as Model Drug

    The most fatal outcomes of prostate carcinoma (PCa) result from hormone-refractory variants of the tumor, especially from metastatic spread rather than from primary tumor burden. The goal of the study was to establish and apply rat MAT-Lu prostate cancer tumor models for improved non-invasive live follow up of tumor growth and metastasis by in vivo bioluminescence. We established luciferase transduced MAT-Lu rat PCa cells and studied tumor growth and metastatic processes in an ectopic as well as orthotopic setting. An intravenous bolus treatment with doxorubicin was used to demonstrate the basic applicability of in vivo imaging to follow up therapeutic intervention in these models. In vitro analysis of tissue homogenates confirmed major metastatic spread of subcutaneous tumors into the lung. Our sensitive method, however, for the first time detects metastasis also in lymph node (11/24), spleen (3/24), kidney (4/24), liver (5/24), and bone tissue (femur or spinal cord - 5/20 and 12/20, respectively). Preliminary data of orthotopic implantation (three animals) showed metastatic invasion to investigated organs in all animals but with varying preference (e.g., to lymph nodes). Intravenous bolus treatment of MAT-Lu PCa with doxorubicin reduced subcutaneous tumor growth by about 50% and the number of animals affected by metastatic lesions in lymph nodes (0/4), lung (3/6) or lumbar spine (0/2), as determined by in vivo imaging and in vitro analysis. Additionally, the possible applicability of the luciferase transduced MAT-Lu model(s) to study basic principles of metronomic therapies via jugular vein catheter, using newly established active microport pumping systems, is presented

  15. Metastasizing, Luciferase Transduced MAT-Lu Rat Prostate Cancer Models: Follow up of Bolus and Metronomic Therapy with Doxorubicin as Model Drug

    Jantscheff, Peter, E-mail: jantscheff@tumorbio.uni-freiburg.de [Tumour Biology Center, Clinical Research, Department Lipids & Liposomes, Breisacher Str.117, D-79106 Freiburg (Germany); Esser, Norbert [ProQinase GmbH, Breisacher Str. 117, D-79106 Freiburg (Germany); Geipel, Andreas; Woias, Peter [Laboratory for Design of Microsystems, Department of Microsystems Engineering (IMTEK), Georges-Köhler-Allee 106, D-79110 Freiburg (Germany); Ziroli, Vittorio [Tumour Biology Center, Clinical Research, Department Lipids & Liposomes, Breisacher Str.117, D-79106 Freiburg (Germany); Goldschmidtboing, Frank [Laboratory for Design of Microsystems, Department of Microsystems Engineering (IMTEK), Georges-Köhler-Allee 106, D-79110 Freiburg (Germany); Massing, Ulrich [Tumour Biology Center, Clinical Research, Department Lipids & Liposomes, Breisacher Str.117, D-79106 Freiburg (Germany)

    2011-06-17

    The most fatal outcomes of prostate carcinoma (PCa) result from hormone-refractory variants of the tumor, especially from metastatic spread rather than from primary tumor burden. The goal of the study was to establish and apply rat MAT-Lu prostate cancer tumor models for improved non-invasive live follow up of tumor growth and metastasis by in vivo bioluminescence. We established luciferase transduced MAT-Lu rat PCa cells and studied tumor growth and metastatic processes in an ectopic as well as orthotopic setting. An intravenous bolus treatment with doxorubicin was used to demonstrate the basic applicability of in vivo imaging to follow up therapeutic intervention in these models. In vitro analysis of tissue homogenates confirmed major metastatic spread of subcutaneous tumors into the lung. Our sensitive method, however, for the first time detects metastasis also in lymph node (11/24), spleen (3/24), kidney (4/24), liver (5/24), and bone tissue (femur or spinal cord - 5/20 and 12/20, respectively). Preliminary data of orthotopic implantation (three animals) showed metastatic invasion to investigated organs in all animals but with varying preference (e.g., to lymph nodes). Intravenous bolus treatment of MAT-Lu PCa with doxorubicin reduced subcutaneous tumor growth by about 50% and the number of animals affected by metastatic lesions in lymph nodes (0/4), lung (3/6) or lumbar spine (0/2), as determined by in vivo imaging and in vitro analysis. Additionally, the possible applicability of the luciferase transduced MAT-Lu model(s) to study basic principles of metronomic therapies via jugular vein catheter, using newly established active microport pumping systems, is presented.

  16. Metastasizing, Luciferase Transduced MAT‑Lu Rat Prostate Cancer Models: Follow up of Bolus and Metronomic Therapy with Doxorubicin as Model Drug

    Peter Woias

    2011-06-01

    Full Text Available The most fatal outcomes of prostate carcinoma (PCa result from hormone-refractory variants of the tumor, especially from metastatic spread rather than from primary tumor burden. The goal of the study was to establish and apply rat MAT-Lu prostate cancer tumor models for improved non-invasive live follow up of tumor growth and metastasis by in vivo bioluminescence. We established luciferase transduced MAT-Lu rat PCa cells and studied tumor growth and metastatic processes in an ectopic as well as orthotopic setting. An intravenous bolus treatment with doxorubicin was used to demonstrate the basic applicability of in vivo imaging to follow up therapeutic intervention in these models. In vitro analysis of tissue homogenates confirmed major metastatic spread of subcutaneous tumors into the lung. Our sensitive method, however, for the first time detects metastasis also in lymph node (11/24, spleen (3/24, kidney (4/24, liver (5/24, and bone tissue (femur or spinal cord - 5/20 and 12/20, respectively. Preliminary data of orthotopic implantation (three animals showed metastatic invasion to investigated organs in all animals but with varying preference (e.g., to lymph nodes. Intravenous bolus treatment of MAT-Lu PCa with doxorubicin reduced subcutaneous tumor growth by about 50% and the number of animals affected by metastatic lesions in lymph nodes (0/4, lung (3/6 or lumbar spine (0/2, as determined by in vivo imaging and in vitro analysis. Additionally, the possible applicability of the luciferase transduced MAT-Lu model(s to study basic principles of metronomic therapies via jugular vein catheter, using newly established active microport pumping systems, is presented.

  17. Monte-Carlo-Model for the aerosol bolus dispersion in the human lung. Part 2. Model predictions for the diseased lung; Monte-Carlo-Modell der Aerosolbolusdispersion in der menschlichen Lunge. Teil 2. Modellvorhersagen fuer die kranke Lunge

    Sturm, R.; Pawlak, E.; Hofmann, W. [Salzburg Univ. (Austria). Abt. fuer Physik und Biophysik

    2007-07-01

    After a mathematical extension of the existing model for the theoretical description of the aerosol bolus dispersion, the behavior of particle pulses in diseased lung structures was simulated. The geometry used for healthy lungs was modified in two aspects: First, a modelling of possible airway obstructions, which usually occur in patients with chronic bronchitis, chronic asthma or cystic fibrosis, was carried out and, second, a theoretical approximation of the emphysema, being observed in lungs of smokers, but also as an accompanying phenomenon in obstructive diseases, was established. According to the modified model, in lungs with airway obstructions the exhaled bolus exhibited a decreased dispersion with respect to healthy subjects, whereas in emphysematous lungs the respective half-width of the peak was increased. Standard deviation and skewness of the bolus were similarly influenced by the modified lung architecture. A combination of airway obstruction and emphysema caused an extensive compensation of individual dispersion effects, complicating a secure distinction from the healthy lung. According to the model, a special diagnostic value may be assigned to the bolus deposition, showing significant deviations from the normal case for all simulated diseases. (orig.)

  18. Adaptive Image Denoising by Mixture Adaptation.

    Luo, Enming; Chan, Stanley H; Nguyen, Truong Q

    2016-10-01

    We propose an adaptive learning procedure to learn patch-based image priors for image denoising. The new algorithm, called the expectation-maximization (EM) adaptation, takes a generic prior learned from a generic external database and adapts it to the noisy image to generate a specific prior. Different from existing methods that combine internal and external statistics in ad hoc ways, the proposed algorithm is rigorously derived from a Bayesian hyper-prior perspective. There are two contributions of this paper. First, we provide full derivation of the EM adaptation algorithm and demonstrate methods to improve the computational complexity. Second, in the absence of the latent clean image, we show how EM adaptation can be modified based on pre-filtering. The experimental results show that the proposed adaptation algorithm yields consistently better denoising results than the one without adaptation and is superior to several state-of-the-art algorithms. PMID:27416593

  19. An isotope approach based on C-13 pulse-chase labelling vs. the root trenching method to separate heterotrophic and autotrophic respiration in cultivated peatlands

    Biasi, C.; Pitkamaki, A. S.; Tavi, N. M.; Koponen, H. T.; Martikainen, P. J. [Univ.of Eastern Finland, Kuopio (Finland). Dept. of Environmental Science], e-mail: christina.biasi@uef.fi

    2012-11-01

    We tested an isotope method based on C-13 pulse-chase labelling for determining the fractional contribution of soil microbial respiration to overall soil respiration in an organic soil (cutaway peatland, eastern Finland), cultivated with the bioenergy crop, reed canary grass. The plants were exposed to CO{sub 2}-13 for five hours and the label was thereafter determined in CO{sub 2} derived from the soil-root system. A two-pool isotope mixing model was used to separate sources of respiration. The isotopic approach showed that a minimum of 50% of the total CO{sub 2} originated from soil-microbial respiration. Even though the method uses undisturbed soil-plant systems, it has limitations concerning the experimental determination of the true isotopic signal of all components contributing to autotrophic respiration. A trenching experiment which was comparatively conducted resulted in a 71% fractional contribution of soil-microbial respiration. This value was likely overestimated. Further studies are needed to evaluate critically the output from these two partitioning approaches. (orig.)

  20. Adaptive Modular Playware

    Lund, Henrik Hautop; Þorsteinsson, Arnar Tumi

    2011-01-01

    In this paper, we describe the concept of adaptive modular playware, where the playware adapts to the interaction of the individual user. We hypothesize that there are individual differences in user interaction capabilities and styles, and that adaptive playware may adapt to the individual user’s...

  1. Adaptive Sticky Generalized Metropolis

    Fabrizio Leisen; Roberto Casarin; David Luengo; Luca Martino

    2013-01-01

    We introduce a new class of adaptive Metropolis algorithms called adaptive sticky algorithms for efficient general-purpose simulation from a target probability distribution. The transition of the Metropolis chain is based on a multiple-try scheme and the different proposals are generated by adaptive nonparametric distributions. Our adaptation strategy uses the interpolation of support points from the past history of the chain as in the adaptive rejection Metropolis. The algorithm efficiency i...

  2. Evapotranspiration modelling of horticultural crops grown with soilless culture [Lycopersicon esculentum Mill.; Gerbera jamesonii Bolus ex Adlam

    This work aims at validating the evapotranspiration model developed by Baille (1994) on tomato and gerbera grown with different concentration of NaCl. Relevant to tomato, the original Baille model was adapted on daily scale and a Boltzman equation for estimating the LAI as a function of thermal day degrees was used. The model was calibrated on data collected in Spring 2004 from a soilless closed-loop tomato culture and validated on datasets collected in 2001 and 2002. Hourly data collected in Spring and Autumn 2005 from a soilless closed-loop gerbera culture grown with different irrigation water quality (0 and 10 meq lE-1 NaCl) were used. Evapotranspiration in gerbera was influenced by different water quality and by radiation levels, while in tomato those factors were negligible. In both crops a good correspondence between estimated and measured data was observed. The developed models will be implemented in a Decision Support System in order to help growers to manage the soilless closed-loop cultivation

  3. Comparison of thrice daily biphasic human insulin (30/70) versus basal detemir & bolus aspart in patients with poorly controlled type 2 diabetes mellitus – A pilot study

    Shanmugasundar, G.; Bhansali, Anil; Walia, Rama; Dutta, Pinaki; Upreti, Vimal

    2012-01-01

    Background & objectives: Conventionally, biphasic human insulin (30/70, BHI) is used twice daily for the management of patients with diabetes. However, this regimen is suboptimal to control post-lunch and/or pre-dinner hyperglycaemia in some patients. This study was undertaken to compare the efficacy and safety of thrice-daily biphasic human insulin (30/70, BHI) versus basal detemir and bolus aspart (BB) in patients with poorly controlled type 2 diabetes mellitus (T2DM). Methods: In this open labelled randomized pilot study, 50 patients with uncontrolled T2DM on twice-daily BHI and insulin sensitizers were randomized either to BHI thrice-daily or BB regimen. HbA1c, six point plasma glucose profile, increment in insulin dose, weight gain, hypoglycaemic episodes and cost were compared between the two treatment groups at the end of 12 wk. Results: Mean HbAlc (±SD) decreased from 9.0±0.9 per cent at randomization to 7.9±0.8 per cent in BHI (P<0.001) and from 9.4±1.3 to 8.2±1.0 per cent in BB regimen (P<0.001) after 12 wk of treatment. The mean (±SEM) weight gain in patients in the BHI regimen was 1.5±0.33 kg compared to 1.4±0.34 kg in the BB regimen. Insulin dose increment at 12 wk was significantly more in the BB regimen 0.46±0.32 U/kg/day compared to 0.15±0.21 U/kg/day in the BHI regimen (P<0.001). The incidence of major as well as minor hypoglycaemic episodes was not different in both the regimen. The BB regimen was more expensive than the BHI regimen (P<0.001). Interpretation & conclusions: The thrice daily biphasic human insulin regimen is non-inferior to the basal bolus insulin analogue regimen in terms efficacy and safety in patients with poorly controlled T2DM. However, these data require further substantiation in large long term prospective studies. PMID:22382187

  4. Expressing Adaptation Strategies Using Adaptation Patterns

    Zemirline, N.; Bourda, Y.; Reynaud, C.

    2012-01-01

    Today, there is a real challenge to enable personalized access to information. Several systems have been proposed to address this challenge including Adaptive Hypermedia Systems (AHSs). However, the specification of adaptation strategies remains a difficult task for creators of such systems. In this paper, we consider the problem of the definition…

  5. Study protocol. ECSSIT - Elective Caesarean Section Syntocinon Infusion Trial. A multi-centre randomised controlled trial of oxytocin (Syntocinon) 5 IU bolus and placebo infusion versus oxytocin 5 IU bolus and 40 IU infusion for the control of blood loss at elective caesarean section.

    Murphy, Deirdre J

    2012-02-01

    BACKGROUND: Caesarean section is one of the most commonly performed major operations in women throughout the world. Rates are escalating, with studies from the United States of America, the United Kingdom, China and the Republic of Ireland reporting rates between 20% and 25%. Operative morbidity includes haemorrhage, anaemia, blood transfusion and in severe cases, maternal death. The value of routine oxytocics in the third stage of vaginal birth has been well established and it has been assumed that these benefits apply to caesarean delivery as well. A slow bolus dose of oxytocin is recommended following delivery of the baby at caesarean section. Some clinicians use an additional infusion of oxytocin for a further period following the procedure. Intravenous oxytocin has a very short half-life (4-10 minutes) therefore the potential advantage of an oxytocin infusion is that it maintains uterine contractility throughout the surgical procedure and immediate postpartum period, when most primary haemorrhages occur. The few trials to date addressing the optimal approach to preventing haemorrhage at caesarean section have been under-powered to evaluate clinically important outcomes. There has been no trial to date comparing the use of an intravenous slow bolus of oxytocin versus an oxytocin bolus and infusion. METHODS AND DESIGN: A multi-centre randomised controlled trial is proposed. The study will take place in five large maternity units in Ireland with collaboration between academics and clinicians in the disciplines of obstetrics and anaesthetics. It will involve 2000 women undergoing elective caesarean section after 36 weeks gestation. The main outcome measure will be major haemorrhage (blood loss >1000 ml). A study involving 2000 women will have 80% power to detect a 36% relative change in the risk of major haemorrhage with two-sided 5% alpha. DISCUSSION: It is both important and timely that we evaluate the optimal approach to the management of the third stage at

  6. Study protocol. ECSSIT - Elective Caesarean Section Syntocinon Infusion Trial. A multi-centre randomised controlled trial of oxytocin (Syntocinon) 5 IU bolus and placebo infusion versus oxytocin 5 IU bolus and 40 IU infusion for the control of blood loss at elective caesarean section.

    Murphy, Deirdre J

    2009-01-01

    BACKGROUND: Caesarean section is one of the most commonly performed major operations in women throughout the world. Rates are escalating, with studies from the United States of America, the United Kingdom, China and the Republic of Ireland reporting rates between 20% and 25%. Operative morbidity includes haemorrhage, anaemia, blood transfusion and in severe cases, maternal death. The value of routine oxytocics in the third stage of vaginal birth has been well established and it has been assumed that these benefits apply to caesarean delivery as well. A slow bolus dose of oxytocin is recommended following delivery of the baby at caesarean section. Some clinicians use an additional infusion of oxytocin for a further period following the procedure. Intravenous oxytocin has a very short half-life (4-10 minutes) therefore the potential advantage of an oxytocin infusion is that it maintains uterine contractility throughout the surgical procedure and immediate postpartum period, when most primary haemorrhages occur. The few trials to date addressing the optimal approach to preventing haemorrhage at caesarean section have been under-powered to evaluate clinically important outcomes. There has been no trial to date comparing the use of an intravenous slow bolus of oxytocin versus an oxytocin bolus and infusion. METHODS AND DESIGN: A multi-centre randomised controlled trial is proposed. The study will take place in five large maternity units in Ireland with collaboration between academics and clinicians in the disciplines of obstetrics and anaesthetics. It will involve 2000 women undergoing elective caesarean section after 36 weeks gestation. The main outcome measure will be major haemorrhage (blood loss >1000 ml). A study involving 2000 women will have 80% power to detect a 36% relative change in the risk of major haemorrhage with two-sided 5% alpha. DISCUSSION: It is both important and timely that we evaluate the optimal approach to the management of the third stage at

  7. Uncertainty in adaptive capacity

    The capacity to adapt is a critical element of the process of adaptation: it is the vector of resources that represent the asset base from which adaptation actions can be made. Adaptive capacity can in theory be identified and measured at various scales, from the individual to the nation. The assessment of uncertainty within such measures comes from the contested knowledge domain and theories surrounding the nature of the determinants of adaptive capacity and the human action of adaptation. While generic adaptive capacity at the national level, for example, is often postulated as being dependent on health, governance and political rights, and literacy, and economic well-being, the determinants of these variables at national levels are not widely understood. We outline the nature of this uncertainty for the major elements of adaptive capacity and illustrate these issues with the example of a social vulnerability index for countries in Africa. (authors)

  8. Adaptive Rationality, Adaptive Behavior and Institutions

    Volchik Vyacheslav, V.

    2015-12-01

    Full Text Available The economic literature focused on understanding decision-making and choice processes reveals a vast collection of approaches to human rationality. Theorists’ attention has moved from absolutely rational, utility-maximizing individuals to boundedly rational and adaptive ones. A number of economists have criticized the concepts of adaptive rationality and adaptive behavior. One of the recent trends in the economic literature is to consider humans irrational. This paper offers an approach which examines adaptive behavior in the context of existing institutions and constantly changing institutional environment. It is assumed that adaptive behavior is a process of evolutionary adjustment to fundamental uncertainty. We emphasize the importance of actors’ engagement in trial and error learning, since if they are involved in this process, they obtain experience and are able to adapt to existing and new institutions. The paper aims at identifying relevant institutions, adaptive mechanisms, informal working rules and practices that influence actors’ behavior in the field of Higher Education in Russia (Rostov Region education services market has been taken as an example. The paper emphasizes the application of qualitative interpretative methods (interviews and discourse analysis in examining actors’ behavior.

  9. Effects of a long-acting trace mineral rumen bolus supplement on growth performance, metabolic profiles, and trace mineral status of growing camels.

    Alhidary, Ibrahim A; Abdelrahman, Mutassim M; Harron, Raafat M

    2016-04-01

    A study was conducted to evaluate the effects of a long-acting trace mineral rumen bolus (TMB) supplement on the productive performance, metabolic profiles, and trace mineral status of growing camels under natural grazing conditions. Fifteen 6-month-old growing male camels (average bodyweight 139.51 ± 26.49 kg) were used in a 150-day trial. Animals were individually housed in a shaded pen and randomly assigned to receive zero (control group, CON), one (TMB1), or two (TMB2) long-acting TMBs. Feed intake was measured weekly, and camels were weighed monthly. Blood samples were collected from all camels on days 1, 30, 60, 90, 120, and 150 to obtain metabolic profiles. Zinc, selenium, copper, cobalt, and manganese concentrations were determined in the diet, serum, and liver. In comparison with controls, giving camels one TMB increased the average daily gain (14.38%; P copper, selenium, cobalt, and manganese were greater (P mineral profiles of camels. Different levels, sources, and synergistic combinations of trace minerals can be used in further studies to elucidate their abilities to increase productive variables as well as their availability and cost to the camel industry. PMID:26894497

  10. Comparison of first pass bolus AIFs extracted from sequential {sup 18}F-FDG PET and DSC-MRI of mice

    Evans, Eleanor, E-mail: ee244@cam.ac.uk [Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0QQ (United Kingdom); Sawiak, Stephen J. [Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0QQ (United Kingdom); Behavioural and Clinical Neuroscience Institute, Department of Experimental Psychology, University of Cambridge, Cambridge, CB2 3EB (United Kingdom); Ward, Alexander O.; Buonincontri, Guido; Hawkes, Robert C.; Adrian Carpenter, T. [Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0QQ (United Kingdom)

    2014-01-11

    Accurate kinetic modelling of in vivo physiological function using positron emission tomography (PET) requires determination of the tracer time–activity curve in plasma, known as the arterial input function (AIF). The AIF is usually determined by invasive blood sampling methods, which are prohibitive in murine studies due to low total blood volumes. Extracting AIFs from PET images is also challenging due to large partial volume effects (PVE). We hypothesise that in combined PET with magnetic resonance imaging (PET/MR), a co-injected bolus of MR contrast agent and PET ligand can be tracked using fast MR acquisitions. This protocol would allow extraction of a MR AIF from MR contrast agent concentration–time curves, at higher spatial and temporal resolution than an image-derived PET AIF. A conversion factor could then be applied to the MR AIF for use in PET kinetic analysis. This work has compared AIFs obtained from sequential DSC-MRI and PET with separate injections of gadolinium contrast agent and {sup 18}F-FDG respectively to ascertain the technique′s validity. An automated voxel selection algorithm was employed to improve MR AIF reproducibility. We found that MR and PET AIFs displayed similar character in the first pass, confirmed by gamma variate fits (p<0.02). MR AIFs displayed reduced PVE compared to PET AIFs, indicating their potential use in PET/MR studies.

  11. Hepatic 123I-insulin binding kinetics in non-insulin-dependent (Type 2) diabetic patients after i.v. bolus administration

    Insulin binding kinetics in the liver were studied in non insulin dependent (Type 2) diabetic patients, by i.v. bolus administration of 123I-insulin. Eight Type 2 diabetic patients were compared with six male volunteers. Uptake of 123I-insulin by liver and kidneys was measured by dynamic scintigraphy with a gamma camera during 30 min. Images of liver and kidneys appeared within 2-3 min after administration of 123I-insulin at a dose of 1 mCi (37 MBq). Peak radioactivity for the liver was found 7.5±0.2 and 6.9±0.3 min after injection for the healthy and the diabetic subjects, respectively (N.S.). The percentage 123I-insulin hepatic uptake was not significantly different for the diabetic and the healthy subjects. Although a large variation exists for maximal uptake of radioactivity within both groups, the data suggest that binding differences in the liver in Type 2 diabetic patients, as compared to healthy subjects, may not account for hepatic insulin resistance. (orig.)

  12. Blood Glucose Control Using a Novel Continuous Blood Glucose Monitor and Repetitive Intravenous Insulin Boluses: Exploiting Natural Insulin Pulsatility as a Principle for a Future Artificial Pancreas

    Nils K. Skjaervold

    2013-01-01

    Full Text Available The aim of this study was to construct a glucose regulatory algorithm by employing the natural pulsatile pattern of insulin secretion and the oscillatory pattern of resting blood glucose levels and further to regulate the blood glucose level in diabetic pigs by this method. We developed a control algorithm based on repetitive intravenous bolus injections of insulin and combined this with an intravascular blood glucose monitor. Four anesthetized pigs were used in the study. The animals developed a mildly diabetic state from streptozotocin pretreatment. They were steadily brought within the blood glucose target range of 4.5–6.0 mmol/L in 21 to 121 min and kept within that range for 128 to 238 min (hypoglycemic values varied from 2.9 to 51.1 min. The study confirmed our hypotheses regarding the feasibility of this new principle for blood glucose control, and the algorithm was constantly improved during the study to produce the best results in the last animals. The main obstacles were the drift of the IvS-1 sensor and problems with the calibration procedure, which calls for an improvement in the sensor stability before this method can be applied fully in new studies in animals and humans.

  13. Adaptive Coordinate Descent

    Loshchilov, Ilya; Schoenauer, Marc; Sebag, Michèle

    2011-01-01

    Independence from the coordinate system is one source of efficiency and robustness for the Covariance Matrix Adaptation Evolution Strategy (CMA-ES). The recently proposed Adaptive Encoding (AE) procedure generalizes CMA-ES adaptive mechanism, and can be used together with any optimization algorithm. Adaptive Encoding gradually builds a transformation of the coordinate system such that the new coordinates are as decorrelated as possible with respect to the objective function. But any optimizat...

  14. Adaptation to climate change

    J. Carmin; K. Tierney; E. Chu; L.M. Hunter; J.T. Roberts; L. Shi

    2015-01-01

    Climate change adaptation involves major global and societal challenges such as finding adequate and equitable adaptation funding and integrating adaptation and development programs. Current funding is insufficient. Debates between the Global North and South center on how best to allocate the financ

  15. Assessment of Model Predictive and Adaptive Glucose Control Strategies for People with Type 1 Diabetes

    Boiroux, Dimitri; Duun-Henriksen, Anne Katrine; Schmidt, Signe;

    2014-01-01

    This paper addresses overnight blood glucose stabilization in people with type 1 diabetes using a Model Predictive Controller (MPC). We use a control strategy based on an adaptive ARMAX model in which we use a Recursive Extended Least Squares (RELS) method to estimate parameters of the stochastic...... part. We compare this model structure with an autoregressive integrated moving average with exogenous input (ARIMAX) structure, and with an autoregressive moving average with exogenous input (ARMAX) model, i.e. without an integrator. Additionally, safety layers improve the controller robustness and...... reduce the risk of hypoglycemia. We test our control strategies on a virtual clinic of 100 randomly generated patients with a representative inter-subject variability. This virtual clinic is based on the Hovorka model. We consider the case where only half of the meal bolus is administered at mealtime...

  16. Five-year Results of Whole Breast Intensity Modulated Radiation Therapy for the Treatment of Early Stage Breast Cancer: The Fox Chase Cancer Center Experience

    Purpose: To report the 5-year outcomes using whole-breast intensity-modulated radiation therapy (IMRT) for the treatment of early-stage-breast cancer at the Fox Chase Cancer Center. Methods and Materials: A total of 946 women with early-stage breast cancer (stage 0, I, or II) were treated with IMRT after surgery with or without systemic therapy from 2003-2010. Whole-breast radiation was delivered via an IMRT technique with a median whole-breast radiation dose of 46 Gy and median tumor bed boost of 14 Gy. Endpoints included local-regional recurrence, cosmesis, and late complications. Results: With a median follow-up of 31 months (range, 1-97 months), there were 12 ipsilateral breast tumor recurrences (IBTR) and one locoregional recurrence. The 5-year actuarial IBTR and locoregional recurrence rates were 2.0% and 2.4%. Physician-reported cosmestic outcomes were available for 645 patients: 63% were considered “excellent”, 33% “good”, and 900 cc, or boost volumes >34 cc were significantly associated with a “fair/poor” cosmetic outcome. Fibrosis, edema, erythema, and telangectasia were also associated with “fair/poor” physician-reported cosmesis; erythema and telangectasia remained significant on multivariate analysis. Patient-reported cosmesis was available for 548 patients, and 33%, 50%, and 17% of patients reported “excellent”, “good”, and “fair/poor” cosmesis, respectively. The use of a boost and increased boost volume: breast volume ratio were significantly associated with “fair/poor” outcomes. No parameter for patient-reported cosmesis was significant on multivariate analysis. The chances of experiencing a treatment related effect was significantly associated with a boost dose ≥16 Gy, receipt of chemotherapy and endocrine therapy, large breast size, and electron boost energy. Conclusions: Whole-breast IMRT is associated with very low rates of local recurrence at 5 years, 83%-98% “good/excellent” cosmetic outcomes, and minimal

  17. Five-year Results of Whole Breast Intensity Modulated Radiation Therapy for the Treatment of Early Stage Breast Cancer: The Fox Chase Cancer Center Experience

    Keller, Lanea M.M., E-mail: Lanea.Keller@fccc.edu [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Sopka, Dennis M. [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Li Tianyu [Department of Biostatistics, Fox Chase Cancer Center, Philadelphia, PA (United States); Klayton, Tracy; Li Jinsheng; Anderson, Penny R. [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Bleicher, Richard J.; Sigurdson, Elin R. [Department of Surgical Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Freedman, Gary M. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA (United States)

    2012-11-15

    Purpose: To report the 5-year outcomes using whole-breast intensity-modulated radiation therapy (IMRT) for the treatment of early-stage-breast cancer at the Fox Chase Cancer Center. Methods and Materials: A total of 946 women with early-stage breast cancer (stage 0, I, or II) were treated with IMRT after surgery with or without systemic therapy from 2003-2010. Whole-breast radiation was delivered via an IMRT technique with a median whole-breast radiation dose of 46 Gy and median tumor bed boost of 14 Gy. Endpoints included local-regional recurrence, cosmesis, and late complications. Results: With a median follow-up of 31 months (range, 1-97 months), there were 12 ipsilateral breast tumor recurrences (IBTR) and one locoregional recurrence. The 5-year actuarial IBTR and locoregional recurrence rates were 2.0% and 2.4%. Physician-reported cosmestic outcomes were available for 645 patients: 63% were considered 'excellent', 33% 'good', and <1.5% 'fair/poor'. For physician-reported cosmesis, boost doses {>=}16 Gy, breast size >900 cc, or boost volumes >34 cc were significantly associated with a 'fair/poor' cosmetic outcome. Fibrosis, edema, erythema, and telangectasia were also associated with 'fair/poor' physician-reported cosmesis; erythema and telangectasia remained significant on multivariate analysis. Patient-reported cosmesis was available for 548 patients, and 33%, 50%, and 17% of patients reported 'excellent', 'good', and 'fair/poor' cosmesis, respectively. The use of a boost and increased boost volume: breast volume ratio were significantly associated with 'fair/poor' outcomes. No parameter for patient-reported cosmesis was significant on multivariate analysis. The chances of experiencing a treatment related effect was significantly associated with a boost dose {>=}16 Gy, receipt of chemotherapy and endocrine therapy, large breast size, and electron boost energy

  18. Does the time of the sampling matter in 13C pulse labeling and chasing experiments? A case study on beech seedlings

    Gavrichkova, Olga; Thoms, Ronny; Muhr, Jan; Karlowsky, Stefan; Keitel, Claudia; Kayler, Zachary; Calfapietra, Carlo; Gessler, Arthur; Brugnoli, Enrico; Gleixner, Gerd

    2016-04-01

    13C pulse labeling and chasing is a valuable and very popular tool for determination of the fate and turnover rates of C in plant-soil systems. Continuous isoflux measurements became an accessible reality allowing to cover completely the diurnal variation in label assimilation and respiration fluxes. Label turnover in multiple pools, especially of those located belowground, is more often assessed instead by isolated day-time samplings. By increasing the sampling frequency of belowground compartments we aimed to catch the short-term diurnal variations in label allocation and to link these processes with label dynamics in the aboveground biomass. For these purposes we labeled 3-m height soil-grown European beech seedlings with 13C enriched CO2 and traced the flow of 13C within belowground plant-soil continuum. Continuous soil isoflux measurements were accompanied by a 3-h-frequency sampling of root and soil material during the first 48 h, followed by a daily sampling in the successive 5 days. The amount of label found in microbial biomass depended partially on the amount of roots in the sample. Microbial biomass C (MBC) and microbial respiration showed very strong correlation, suggesting the possibility to use one as a proxy of the other. MBC enrichment showed a clear diurnal pattern with night-time and early morning peaks. These peaks were similar in shape and shifted by one sampling when compared to root sugars enrichment. Soil respiration showed instead a single bell-shape peak in 13C, likely due to a sequence of peaks of root and microbial origin. 13C flow into soil microbial functional groups was assessed less frequently through phospholipid fatty acid analyses (PLFA). The microorganisms were separated into two distinct groups by the time of the appearance of the label in the single PLFAs. The first group was characterized by a fast appearance of the label and higher enrichment and was composed of Gram negative bacteria and saprotrophic fungi likely living in

  19. Dose regimens, variability, and complications associated with using repeat-bolus dosing to extend a surgical plane of anesthesia in laboratory mice.

    Jaber, Samer M; Hankenson, F Claire; Heng, Kathleen; McKinstry-Wu, Andrew; Kelz, Max B; Marx, James O

    2014-11-01

    Extending a surgical plane of anesthesia in mice by using injectable anesthetics typically is accomplished by repeat-bolus dosing. We compared the safety and efficacy of redosing protocols administered either during an anesthetic surgical plane (maintaining a continuous surgical plane, CSP), or immediately after leaving this plane (interrupted surgical plane, ISP) in C57BL/6J mice. Anesthesia was induced with ketamine, xylazine, and acepromazine (80, 8, and 1 mg/kg IP, respectively), and redosing protocols included 25% (0.25K), 50% (0.5K), or 100% (1.0K) of the initial ketamine dose or 25% (0.25KX) or 50% (0.5KX) of the initial ketamine-xylazine dose. In the ISP group, the surgical plane was extended by 13.8 ± 2.1 min (mean ± SEM) after redosing for the 0.25K redose with 50% returning to a surgical plane, 42.7 ± 4.5 min for the 0.5K redose with 88% returning to a surgical plane, and 44.3 ± 15.4 min for the 1.0K redose, 52.8 ± 7.2 min for the 0.25KX redose, and 45.9 ± 2.9 min for the 0.5KX redose, with 100% of mice returning to a surgical plane of anesthesia in these 3 groups. Mortality rates for ISP groups were 0%, 12%, 33%, 12%, and 18%, respectively. Mice in CSP groups had 50% mortality, independent of the repeat-dosing protocol. We recommend redosing mice with either 50% of the initial ketamine dose or 25% of the initial ketamine-xylazine dose immediately upon return of the pedal withdrawal reflex to extend the surgical plane of anesthesia in mice, optimize the extension of the surgical plane, and minimize mortality. PMID:25650976

  20. Metabolism of the A{sub 1} adenosine receptor PET ligand [{sup 18}F]CPFPX by CYP1A2: implications for bolus/infusion PET studies

    Matusch, Andreas [Institute of Medicine, Research Center Juelich GmbH, D-52425 Juelich (Germany); Meyer, Philipp T. [Department of Neurology, University Hospital Aachen, D-52074 Aachen (Germany); Bier, Dirk [Institute for Neuroscience and Biophysics (INB4)-Nuclear Chemistry, Research Center Juelich GmbH, D-52425 Juelich (Germany); Holschbach, Marcus H. [Institute for Neuroscience and Biophysics (INB4)-Nuclear Chemistry, Research Center Juelich GmbH, D-52425 Juelich (Germany); Woitalla, Dirk [Neurological Department, Ruhr-University Bochum, D-44791 Bochum (Germany); Elmenhorst, David [Institute of Medicine, Research Center Juelich GmbH, D-52425 Juelich (Germany); Winz, Oliver H. [Institute of Medicine, Research Center Juelich GmbH, D-52425 Juelich (Germany); Zilles, Karl [Institute of Medicine, Research Center Juelich GmbH, D-52425 Juelich (Germany); Bauer, Andreas [Institute of Medicine, Research Center Juelich GmbH, D-52425 Juelich (Germany)]. E-mail: an.bauer@fz-juelich.de

    2006-10-15

    The A{sub 1} adenosine receptor positron emission tomography (PET) ligand 8-cyclopentyl-3-(3-[{sup 18}F]fluoropropyl)-1-propylxanthine ([{sup 18}F]CPFPX, ) undergoes a fast hepatic metabolism. An optimal design of PET quantitation approaches (e.g., bolus/infusion studies) necessitates the knowledge of factors that influence this metabolism. Metabolites of were separated by radio thin-layer chromatography. Metabolism in vivo, in pooled human liver microsomes and in recombinant human cytochrome isoenzyme preparations was studied. Dynamic PET studies using were performed on three controls and two patients, one treated with the antidepressant and inhibitor of cytochrome CYP1A2 fluvoxamine, the other suffering from liver cirrhosis. CPFPX is metabolized by cytochrome CYP1A2 with high selectivity [K {sub M}=1.1 {mu}M (95% confidence interval, or CI, 0.6-2.0 {mu}M) and V {sub max}=243 pmol min{sup -1} mg{sup -1} (95% CI, 112-373 pmol min{sup -1} mg{sup -1}) corresponding to 2.4 pmol min{sup -1} pmol{sup -1} cytochrome P-450]. This metabolism can competitively be inhibited by fluvoxamine with K {sub I}=68 nM (95% CI, 34-138 nM). At least eight compounds found in human plasma and in the CYP1A2 in vitro preparations have an identical migration pattern and account together for >90% and >80% of the respective metabolite yield. Metabolism was considerably delayed in the two patients. In conclusion, is metabolized by cytochrome CYP1A2. Its metabolism is therefore subdued to disease-related or xenobiotic-induced changes of CYP1A2 activity. The identification of the metabolic pathway of 1 allows to optimize image quantification in A{sub 1} adenosine receptor PET studies.

  1. 14CO2 pulse-12CO2 chase analyses of C4-acid metabolism in C3-C4 intermediate species of Flaveria at the CO2 compensation concentration (r)

    Photosynthetic C4-acid metabolism in leaves of C3-C4 intermediate Flaveria species was examined by 14CO2 pulse-12CO2 chase experiments conducted at external CO2-levels approximating air and γ. Analysis of the percent distribution of 14C after a 10-s pulse showed an enhanced labeling of malate and aspartate at γ in the C3-C4 species. This stimulation of 14CO2 fixation by PEP carboxylase ranged from 1.7-(F. floridana) to 3.6-fold (F. anomala). A 12CO2-chase at γ revealed a significant turnover of C4 acids for only F. floridana. C4-acid labeling in C3 and C4 Flaveria species was relatively unresponsive to changes in pCO2. These data imply that the C3-C4 intermediate Flaveria species with less advanced C4 attributes have a greater capacity for increased CO2 fixation via PEP carboxylase at γ versus air. Thus, labeling of C3-C4 leaves at Σ may be an effective tool for assessing the degree of true C4-photosynthesis as well as the potential mechanism involved in reducing photorespiration

  2. Origins of adaptive immunity.

    Liongue, Clifford; John, Liza B; Ward, Alister

    2011-01-01

    Adaptive immunity, involving distinctive antibody- and cell-mediated responses to specific antigens based on "memory" of previous exposure, is a hallmark of higher vertebrates. It has been argued that adaptive immunity arose rapidly, as articulated in the "big bang theory" surrounding its origins, which stresses the importance of coincident whole-genome duplications. Through a close examination of the key molecules and molecular processes underpinning adaptive immunity, this review suggests a less-extreme model, in which adaptive immunity emerged as part of longer evolutionary journey. Clearly, whole-genome duplications provided additional raw genetic materials that were vital to the emergence of adaptive immunity, but a variety of other genetic events were also required to generate some of the key molecules, whereas others were preexisting and simply co-opted into adaptive immunity. PMID:21395512

  3. Technology transfer for adaptation

    Biagini, Bonizella; Kuhl, Laura; Gallagher, Kelly Sims; Ortiz, Claudia

    2014-09-01

    Technology alone will not be able to solve adaptation challenges, but it is likely to play an important role. As a result of the role of technology in adaptation and the importance of international collaboration for climate change, technology transfer for adaptation is a critical but understudied issue. Through an analysis of Global Environment Facility-managed adaptation projects, we find there is significantly more technology transfer occurring in adaptation projects than might be expected given the pessimistic rhetoric surrounding technology transfer for adaptation. Most projects focused on demonstration and early deployment/niche formation for existing technologies rather than earlier stages of innovation, which is understandable considering the pilot nature of the projects. Key challenges for the transfer process, including technology selection and appropriateness under climate change, markets and access to technology, and diffusion strategies are discussed in more detail.

  4. Diffusion Adaptation over Networks

    Sayed, Ali H

    2012-01-01

    Adaptive networks are well-suited to perform decentralized information processing and optimization tasks and to model various types of self organized and complex behavior encountered in nature. Adaptive networks consist of a collection of agents with processing and learning abilities. The agents are linked together through a connection topology, and they cooperate with each other through local interactions to solve distributed inference problems in real-time. The continuous diffusion of information across the network enables agents to adapt their performance in relation to changing data and network conditions; it also results in improved adaptation and learning performance relative to non-cooperative networks. This article provides an overview of diffusion strategies for adaptation and learning over networks. The article is divided into several sections: 1. Motivation; 2. Mean-Square-Error Estimation; 3. Distributed Optimization via Diffusion Strategies; 4. Adaptive Diffusion Strategies; 5. Performance of Ste...

  5. Consciousness And Adaptive Behavior

    Sieb, Richard/A.

    2005-01-01

    Consciousness has resisted scientific explanation for centuries. The main problem in explaining consciousness is its subjectivity. Subjective systems may be adaptive. Humans can produce voluntary new or novel intentional (adaptive) action and such action is always accompanied by consciousness. Action normally arises from perception. Perception must be rerepresented in order to produce new or novel adaptive action. The internal explicit states produced by a widespread nonlinear emergen...

  6. Human Adaptations: Free divers

    Tournat, Troy Z.

    2014-01-01

    Freediving has been around for thousands of years and was only way to dive until the inventionof oxygen tanks in the 19th century. Around the world, people dove for goods such as pearls, andtoday people freedive for sport. Divers stretch the limit of their body and mind’s capabilitiesthrough psychological adaptations from thermal, respiratory, and cardiovascular responses.Findings conclude that thermal adaptations are a similar process to cold adaptive response. Withthe implementation of wets...

  7. Adaptive Multimedia Retrieval: Semantics, Context, and Adaptation

    This book constitutes the thoroughly refereed post-conference proceedings of the 10th International Conference on Adaptive Multimedia Retrieval, AMR 2012, held in Copenhagen, Denmark, in October 2012. The 17 revised full papers presented were carefully reviewed and selected from numerous submissi......This book constitutes the thoroughly refereed post-conference proceedings of the 10th International Conference on Adaptive Multimedia Retrieval, AMR 2012, held in Copenhagen, Denmark, in October 2012. The 17 revised full papers presented were carefully reviewed and selected from numerous...

  8. Decentralized adaptive control

    Oh, B. J.; Jamshidi, M.; Seraji, H.

    1988-01-01

    A decentralized adaptive control is proposed to stabilize and track the nonlinear, interconnected subsystems with unknown parameters. The adaptation of the controller gain is derived by using model reference adaptive control theory based on Lyapunov's direct method. The adaptive gains consist of sigma, proportional, and integral combination of the measured and reference values of the corresponding subsystem. The proposed control is applied to the joint control of a two-link robot manipulator, and the performance in computer simulation corresponds with what is expected in theoretical development.

  9. Adaptive Wireless Transceiver Project

    National Aeronautics and Space Administration — Wireless technologies are an increasingly attractive means for spatial data, input, manipulation, and distribution. Mobitrum is proposing an innovative Adaptive...

  10. Chasing White-Light Flares

    Hudson, H. S.

    2016-06-01

    In this memoir I describe my life in research, mostly in the area of solar physics. The recurring theme is "white-light flares," and several sections of this paper deal with this and related phenomena; I wind up describing how I see the state of the art in this still-interesting and crucially important (as it has been since 1859) area of flare research. I also describe my participation in two long-lived satellite programs dedicated to solar observations (Yohkoh and RHESSI) and elaborate on their discoveries. These have both helped with white-light flares both directly and also with closely related X-ray and γ-ray emissions), with the result that this article leans heavily in that direction.

  11. Chasing extreme blazars with INTEGRAL

    Bassani, Loredana; Landi, R; Malizia, A; Bird, A J; Bazzano, A; Ubertini, P

    2013-01-01

    Within the blazar population, hard X-ray selected objects are of particular interest as they tend to lie at each end of the blazar sequence. In particular, flat spectrum radio quasars located at high redshifts display the most powerful jets, the largest black hole masses and the most luminous accretion disks: their spectral energy distribution has a Compton peak in the sub-MeV region which favours their detection by instruments like INTEGRAL/IBIS and Swift/BAT. These sources are even more extreme than blazars selected in other wavebands, like, for example, the gamma-ray range explored by Fermi. Here we report on a sample of 12 high redshift blazars detected so far by INTEGRAL, including 3 newly identified objects. Some properties of the combined IBIS/BAT sample of high redshift blazars (z>2) are also compared to those of a similar similar sample obtained by Fermi.

  12. Einstein Chases a Light Beam

    Weinstein, Galina

    2012-01-01

    This is a prelude to a book which I intend to publish. This paper describes my temporary thoughts on Einstein's pathway to the special theory of relativity. See my papers on my thoughts on Einstein's pathway to his general theory of relativity. Never say that you know how Einstein had arrived at his special theory of relativity, even if you read his letters to his wife and friends, and some other primary documents. Einstein gave many talks and wrote pieces, but at the end of the day, he told ...

  13. Chasing White-Light Flares

    Hudson, H. S.

    2016-05-01

    In this memoir I describe my life in research, mostly in the area of solar physics. The recurring theme is "white-light flares," and several sections of this paper deal with this and related phenomena; I wind up describing how I see the state of the art in this still-interesting and crucially important (as it has been since 1859) area of flare research. I also describe my participation in two long-lived satellite programs dedicated to solar observations ( Yohkoh and RHESSI) and elaborate on their discoveries. These have both helped with white-light flares both directly and also with closely related X-ray and γ-ray emissions), with the result that this article leans heavily in that direction.

  14. Behavioral Adaptation and Acceptance

    Martens, M.H.; Jenssen, G.D.

    2012-01-01

    One purpose of Intelligent Vehicles is to improve road safety, throughput, and emissions. However, the predicted effects are not always as large as aimed for. Part of this is due to indirect behavioral changes of drivers, also called behavioral adaptation. Behavioral adaptation (BA) refers to uninte

  15. Behavioural adaptation and acceptance

    Martens, M.H.; Jenssen, G.D.; Eskandarian, A.

    2012-01-01

    One purpose of Intelligent Vehicles is to improve road safety, throughput, and emissions. However, the predicted effects are not always as large as aimed for. Part of this is due to indirect behavioral changes of drivers, also called behavioral adaptation. Behavioral adaptation (BA) refers to uninte

  16. Adaptive Capacity and Traps

    William A. Brock

    2008-12-01

    Full Text Available Adaptive capacity is the ability of a living system, such as a social–ecological system, to adjust responses to changing internal demands and external drivers. Although adaptive capacity is a frequent topic of study in the resilience literature, there are few formal models. This paper introduces such a model and uses it to explore adaptive capacity by contrast with the opposite condition, or traps. In a social–ecological rigidity trap, strong self-reinforcing controls prevent the flexibility needed for adaptation. In the model, too much control erodes adaptive capacity and thereby increases the risk of catastrophic breakdown. In a social–ecological poverty trap, loose connections prevent the mobilization of ideas and resources to solve problems. In the model, too little control impedes the focus needed for adaptation. Fluctuations of internal demand or external shocks generate pulses of adaptive capacity, which may gain traction and pull the system out of the poverty trap. The model suggests some general properties of traps in social–ecological systems. It is general and flexible, so it can be used as a building block in more specific and detailed models of adaptive capacity for a particular region.

  17. Adapt or Become Extinct!

    Goumas, Georgios; McKee, Sally A.; Själander, Magnus;

    2011-01-01

    boundaries (walls) for applications which limit software development (parallel programming wall), performance (memory wall, communication wall) and viability (power wall). The only way to survive in such a demanding environment is by adaptation. In this paper we discuss how dynamic information collected...... during the execution of an application can be utilized to adapt the execution context and may lead to performance gains beyond those provided by static information and compile-time adaptation. We consider specialization based on dynamic information like user input, architectural characteristics such as...... from static analysis (either during ahead-of-time or just-in-time) compilation. We extend the notion of information-driven adaptation and outline the architecture of an infrastructure designed to enable information ow and adaptation throughout the life-cycle of an application....

  18. Appraising Adaptive Management

    Kai N. Lee

    1999-12-01

    Full Text Available Adaptive management is appraised as a policy implementation approach by examining its conceptual, technical, equity, and practical strengths and limitations. Three conclusions are drawn: (1 Adaptive management has been more influential, so far, as an idea than as a practical means of gaining insight into the behavior of ecosystems utilized and inhabited by humans. (2 Adaptive management should be used only after disputing parties have agreed to an agenda of questions to be answered using the adaptive approach; this is not how the approach has been used. (3 Efficient, effective social learning, of the kind facilitated by adaptive management, is likely to be of strategic importance in governing ecosystems as humanity searches for a sustainable economy.

  19. Adaptive noise cancellation

    In this report we describe the concept of adaptive noise canceling, an alternative method of estimating signals corrupted by additive noise of interference. The method uses 'primary' input containing the corrupted signal and a 'reference' input containing noise correlated in some unknown way with the primary noise, the reference input is adaptively filtered and subtracted from the primary input to obtain the signal estimate. Adaptive filtering before subtraction allows the treatment of inputs that are deterministic or stochastic, stationary or time variable. When the reference input is free of signal and certain other conditions are met then noise in the primary input can be essentially eliminated without signal distortion. It is further shown that the adaptive filter also acts as notch filter. Simulated results illustrate the usefulness of the adaptive noise canceling technique. (author)

  20. Adaptive signal processor

    An experimental, general purpose adaptive signal processor system has been developed, utilizing a quantized (clipped) version of the Widrow-Hoff least-mean-square adaptive algorithm developed by Moschner. The system accommodates 64 adaptive weight channels with 8-bit resolution for each weight. Internal weight update arithmetic is performed with 16-bit resolution, and the system error signal is measured with 12-bit resolution. An adapt cycle of adjusting all 64 weight channels is accomplished in 8 μsec. Hardware of the signal processor utilizes primarily Schottky-TTL type integrated circuits. A prototype system with 24 weight channels has been constructed and tested. This report presents details of the system design and describes basic experiments performed with the prototype signal processor. Finally some system configurations and applications for this adaptive signal processor are discussed

  1. Test-retest reproducibility of the metabotropic glutamate receptor 5 ligand [18F]FPEB with bolus plus constant infusion in humans

    [18F]FPEB is a promising PET radioligand for the metabotropic glutamate receptor 5 (mGluR5), a potential target for the treatment of neuropsychiatric diseases. The purpose of this study was to evaluate the test-retest reproducibility of [18F]FPEB in the human brain. Seven healthy male subjects were scanned twice, 3 - 11 weeks apart. Dynamic data were acquired using bolus plus infusion of 162 ± 32 MBq [18F]FPEB. Four methods were used to estimate volume of distribution (VT): equilibrium analysis (EQ) using arterial (EQA) or venous input data (EQV), MA1, and a two-tissue compartment model (2 T). Binding potential (BPND) was also estimated using cerebellar white matter (CWM) or gray matter (CGM) as the reference region using EQ, 2 T and MA1. Absolute test-retest variability (aTRV) of VT and BPND were calculated for each method. Venous blood measurements (CV) were compared with arterial input (CA) to examine their usability in EQ analysis. Regional VT estimated by the four methods displayed a high degree of agreement (r2 ranging from 0.83 to 0.99 among the methods), although EQA and EQV overestimated VT by a mean of 9 % and 7 %, respectively, compared to 2 T. Mean values of aTRV of VT were 11 % by EQA, 12 % by EQV, 14 % by MA1 and 14 % by 2 T. Regional BPND also agreed well among the methods and mean aTRV of BPND was 8 - 12 % (CWM) and 7 - 9 % (CGM). Venous and arterial blood concentrations of [18F]FPEB were well matched during equilibrium (CV = 1.01 . CA, r2 = 0.95). [18F]FPEB binding shows good TRV with minor differences among analysis methods. Venous blood can be used as an alternative for input function measurement instead of arterial blood in EQ analysis. Thus, [18F]FPEB is an excellent PET imaging tracer for mGluR5 in humans. (orig.)

  2. Randomized trial comparing conventional intravenous bolus FEC and FEC with high-dose infusional 5-fluorouracil as first-line treatment of advanced breast cancer.

    Hebbar, M; Bonneterre, J; Fournier, C; Vanlemmens, L; Pion, J M; Adenis, A; Kamus, E; Hecquet, B; Conroy, T; Tubiana-Hulin, M

    1995-01-01

    FEC (5-FU 500 mg/m2, epirubicin 50 mg/m2, and cyclophosphamide 500 mg/m2) administered as a conventional bolus schedule is widely used in treatment of advanced breast cancer. 5-FU is thought to be more efficient when administered at high doses as a continuous infusion. The aim of this study was to compare the response rate, time to treatment failure, and overall survival obtained with standard FEC regimen (group A) and FEC with high-dose infusional 5-FU (750 mg/m2 per day/days 1 to 5) (group B). One hundred and seventy-eight patients entered this study, 89 in each arm; 10 were noneligible. Both groups were comparable for age, performance status, menopausal status, hormonal receptor status and prior treatment of the initial tumor, duration of relapse free interval, and type and number of disease sites. One hundred and forth patients were evaluable for efficacy. The response rate was 33.3% in group A (1.4% complete response-CR), and 39.4% in group B (9.8% CR) (ns). In an intent to treat basis (n = 168) the response rates were 26.8% and 34.1%, respectively, in groups A and B (ns). The response rate in liver metastasis was significantly higher in group B (57.1%) than in group A (20.0%) (P = 0.03). The time to treatment failure and overall survival were not different between the two groups. One hundred and fifty-three patients were evaluable for toxicity. 10.7% of the patients in group A and 16.0% in group B stopped treatment due to toxicity. Stomatitis was more frequently observed in group B than in group A (46.7% versus 2.6%, respectively, p < 10(-9)). The rates of other side effects were similar in the two groups. In conclusion, the two regimens gave similar overall response rates, time to treatment failure and survival, but infusional 5-FU yielded a better response rate in the liver metastasis. PMID:8934728

  3. Test-retest reproducibility of the metabotropic glutamate receptor 5 ligand [{sup 18}F]FPEB with bolus plus constant infusion in humans

    Park, Eunkyung; Sullivan, Jenna M.; Planeta, Beata; Gallezot, Jean-Dominique; Lim, Keunpoong; Lin, Shu-Fei; Ropchan, Jim; Huang, Yiyun; Carson, Richard E. [Yale School of Medicine, PET Center, Department of Diagnostic Radiology, 801 Howard Avenue, PO Box 208048, New Haven, CT (United States); McCarthy, Timothy J. [Pfizer Worldwide Research and Development, Cambridge, MA (United States); Ding, Yu-Shin [New York University School of Medicine, Department of Radiology, New York, NY (United States); Morris, Evan D.; Williams, Wendol A. [Yale School of Medicine, PET Center, Department of Diagnostic Radiology, 801 Howard Avenue, PO Box 208048, New Haven, CT (United States); Yale School of Medicine, Department of Psychiatry, New Haven, CT (United States)

    2015-09-15

    [{sup 18}F]FPEB is a promising PET radioligand for the metabotropic glutamate receptor 5 (mGluR5), a potential target for the treatment of neuropsychiatric diseases. The purpose of this study was to evaluate the test-retest reproducibility of [{sup 18}F]FPEB in the human brain. Seven healthy male subjects were scanned twice, 3 - 11 weeks apart. Dynamic data were acquired using bolus plus infusion of 162 ± 32 MBq [{sup 18}F]FPEB. Four methods were used to estimate volume of distribution (V{sub T}): equilibrium analysis (EQ) using arterial (EQ{sub A}) or venous input data (EQ{sub V}), MA1, and a two-tissue compartment model (2 T). Binding potential (BP{sub ND}) was also estimated using cerebellar white matter (CWM) or gray matter (CGM) as the reference region using EQ, 2 T and MA1. Absolute test-retest variability (aTRV) of V{sub T} and BP{sub ND} were calculated for each method. Venous blood measurements (C{sub V}) were compared with arterial input (C{sub A}) to examine their usability in EQ analysis. Regional V{sub T} estimated by the four methods displayed a high degree of agreement (r{sup 2} ranging from 0.83 to 0.99 among the methods), although EQ{sub A} and EQ{sub V} overestimated V{sub T} by a mean of 9 % and 7 %, respectively, compared to 2 T. Mean values of aTRV of V{sub T} were 11 % by EQ{sub A}, 12 % by EQ{sub V}, 14 % by MA1 and 14 % by 2 T. Regional BP{sub ND} also agreed well among the methods and mean aTRV of BP{sub ND} was 8 - 12 % (CWM) and 7 - 9 % (CGM). Venous and arterial blood concentrations of [{sup 18}F]FPEB were well matched during equilibrium (C{sub V} = 1.01 . C{sub A}, r{sup 2} = 0.95). [{sup 18}F]FPEB binding shows good TRV with minor differences among analysis methods. Venous blood can be used as an alternative for input function measurement instead of arterial blood in EQ analysis. Thus, [{sup 18}F]FPEB is an excellent PET imaging tracer for mGluR5 in humans. (orig.)

  4. Feasibility of power contrast injections and bolus triggering during CT scans in oncologic patients with totally implantable venous access ports of the forearm

    Background: Conventional totally implantable venous access ports (TIVAPs) are not approved for power contrast injections but often remain the only venous access site in oncologic patients. Therefore, these devices can play an important role if patients with a TIVAP are scheduled for a contrast-enhanced computed tomography (ceCT) as vascular access may become more difficult during the course of chemotherapy. Purpose: To evaluate the feasibility and safety of power injections in conventional TIVAPs in the forearm and to analyze the feasibility of bolus triggering during CT scans. Material and Methods: In this retrospective study we analyzed 177 power injections in 141 patients with TIVAPs in the forearm. Between October 2008 and March 2010 all patients underwent power injections (1.5 mL/s, 150 psi) via the TIVAP for ceCT because conventional vascular access via a peripheral vein had failed. Adequate functioning and catheter's tip location after injection were evaluated. Peak injection pressure and attenuation levels of aorta, liver and spleen were analyzed and compared with results of 50 patients who were injected via classical peripheral cannulas (3 mL/s, 300 psi). Feasibility of automatic scan initiation was evaluated. In vitro the port was stressed with 5 mL/s (300 psi). Results: One TIVAP showed tip dislocation with catheter rupture. Three (2.1%) devices were explanted owing to assumed infection within 4 weeks after the injection. Mean injection pressure was 121.9 ±24.1 psi. Triggering with automatic scan initiation succeeded in 13/44 (29.6%) scans. Injection via classical cannulas resulted in significantly higher enhancement (p < 0.05). In vitro the port system tolerated flow rates of up to 5 mL/s, injection pressures of up to 338 psi. Conclusion: Power injection is a safe alternative for patients with TIVAPs in the forearm if classic vascular access ultimately fails. Triggering was successful in one-third of the attempts. Image quality in the arterial phase

  5. The process of organisational adaptation through innovations, and organisational adaptability

    Tikka, Tommi

    2010-01-01

    This study is about the process of organisational adaptation and organisational adaptability. The study generates a theoretical framework about organisational adaptation behaviour and conditions that have influence on success of organisational adaptation. The research questions of the study are: How does an organisation adapt through innovations, and which conditions enhance or impede organisational adaptation through innovations? The data were gathered from five case organisations withi...

  6. Adaptive network countermeasures.

    McClelland-Bane, Randy; Van Randwyk, Jamie A.; Carathimas, Anthony G.; Thomas, Eric D.

    2003-10-01

    This report describes the results of a two-year LDRD funded by the Differentiating Technologies investment area. The project investigated the use of countermeasures in protecting computer networks as well as how current countermeasures could be changed in order to adapt with both evolving networks and evolving attackers. The work involved collaboration between Sandia employees and students in the Sandia - California Center for Cyber Defenders (CCD) program. We include an explanation of the need for adaptive countermeasures, a description of the architecture we designed to provide adaptive countermeasures, and evaluations of the system.

  7. Introduction to adaptive arrays

    Monzingo, Bob; Haupt, Randy

    2011-01-01

    This second edition is an extensive modernization of the bestselling introduction to the subject of adaptive array sensor systems. With the number of applications of adaptive array sensor systems growing each year, this look at the principles and fundamental techniques that are critical to these systems is more important than ever before. Introduction to Adaptive Arrays, 2nd Edition is organized as a tutorial, taking the reader by the hand and leading them through the maze of jargon that often surrounds this highly technical subject. It is easy to read and easy to follow as fundamental concept

  8. [Adaptive optics for ophthalmology].

    Saleh, M

    2016-04-01

    Adaptive optics is a technology enhancing the visual performance of an optical system by correcting its optical aberrations. Adaptive optics have already enabled several breakthroughs in the field of visual sciences, such as improvement of visual acuity in normal and diseased eyes beyond physiologic limits, and the correction of presbyopia. Adaptive optics technology also provides high-resolution, in vivo imaging of the retina that may eventually help to detect the onset of retinal conditions at an early stage and provide better assessment of treatment efficacy. PMID:27019970

  9. Theory of adaptive adjustment

    Weihong Huang

    2000-01-01

    Full Text Available Conventional adaptive expectation as a mechanism of stabilizing an unstable economic process is reexamined through a generalization to an adaptive adjustment framework. The generic structures of equilibria that can be stabilized through an adaptive adjustment mechanism are identified. The generalization can be applied to a broad class of discrete economic processes where the variables interested can be adjusted or controlled directly by economic agents such as in cobweb dynamics, Cournot games, Oligopoly markets, tatonnement price adjustment, tariff games, population control through immigration etc.

  10. Symmetry Adapted Basis Sets

    Avery, John Scales; Rettrup, Sten; Avery, James Emil

    In theoretical physics, theoretical chemistry and engineering, one often wishes to solve partial differential equations subject to a set of boundary conditions. This gives rise to eigenvalue problems of which some solutions may be very difficult to find. For example, the problem of finding...... such problems can be much reduced by making use of symmetry-adapted basis functions. The conventional method for generating symmetry-adapted basis sets is through the application of group theory, but this can be difficult. This book describes an easier method for generating symmetry-adapted basis sets...

  11. Asimovian Adaptive Agents

    Gordon, D F

    2011-01-01

    The goal of this research is to develop agents that are adaptive and predictable and timely. At first blush, these three requirements seem contradictory. For example, adaptation risks introducing undesirable side effects, thereby making agents' behavior less predictable. Furthermore, although formal verification can assist in ensuring behavioral predictability, it is known to be time-consuming. Our solution to the challenge of satisfying all three requirements is the following. Agents have finite-state automaton plans, which are adapted online via evolutionary learning (perturbation) operators. To ensure that critical behavioral constraints are always satisfied, agents' plans are first formally verified. They are then reverified after every adaptation. If reverification concludes that constraints are violated, the plans are repaired. The main objective of this paper is to improve the efficiency of reverification after learning, so that agents have a sufficiently rapid response time. We present two solutions: ...

  12. Limits to adaptation

    Dow, Kirstin; Berkhout, Frans; Preston, Benjamin L.; Klein, Richard J. T.; Midgley, Guy; Shaw, M. Rebecca

    2013-04-01

    An actor-centered, risk-based approach to defining limits to social adaptation provides a useful analytic framing for identifying and anticipating these limits and informing debates over society's responses to climate change.

  13. The genomics of adaptation.

    Radwan, Jacek; Babik, Wiesław

    2012-12-22

    The amount and nature of genetic variation available to natural selection affect the rate, course and outcome of evolution. Consequently, the study of the genetic basis of adaptive evolutionary change has occupied biologists for decades, but progress has been hampered by the lack of resolution and the absence of a genome-level perspective. Technological advances in recent years should now allow us to answer many long-standing questions about the nature of adaptation. The data gathered so far are beginning to challenge some widespread views of the way in which natural selection operates at the genomic level. Papers in this Special Feature of Proceedings of the Royal Society B illustrate various aspects of the broad field of adaptation genomics. This introductory article sets up a context and, on the basis of a few selected examples, discusses how genomic data can advance our understanding of the process of adaptation. PMID:23097510

  14. Adaptive shared control system

    Sanders, David

    2009-01-01

    A control system to aid mobility is presented that is intended to assist living independently and that provides physical guidance. The system has two levels: a human machine interface and an adaptive shared controller.

  15. Adaptations, exaptations, and spandrels.

    Buss, D M; Haselton, M G; Shackelford, T K; Bleske, A L; Wakefield, J C

    1998-05-01

    Adaptation and natural selection are central concepts in the emerging science of evolutionary psychology. Natural selection is the only known causal process capable of producing complex functional organic mechanisms. These adaptations, along with their incidental by-products and a residue of noise, comprise all forms of life. Recently, S. J. Gould (1991) proposed that exaptations and spandrels may be more important than adaptations for evolutionary psychology. These refer to features that did not originally arise for their current use but rather were co-opted for new purposes. He suggested that many important phenomena--such as art, language, commerce, and war--although evolutionary in origin, are incidental spandrels of the large human brain. The authors outline the conceptual and evidentiary standards that apply to adaptations, exaptations, and spandrels and discuss the relative utility of these concepts for psychological science. PMID:9612136

  16. Adapt or Die

    Brody, Joshua Eric; Larsen, Kasper Green

    2015-01-01

    In this paper, we study the role non-adaptivity plays in maintaining dynamic data structures. Roughly speaking, a data structure is non-adaptive if the memory locations it reads and/or writes when processing a query or update depend only on the query or update and not on the contents of previously...... read cells. We study such non-adaptive data structures in the cell probe model. This model is one of the least restrictive lower bound models and in particular, cell probe lower bounds apply to data structures developed in the popular word-RAM model. Unfortunately, this generality comes at a high cost......: the highest lower bound proved for any data structure problem is only polylogarithmic. Our main result is to demonstrate that one can in fact obtain polynomial cell probe lower bounds for non-adaptive data structures. To shed more light on the seemingly inherent polylogarithmic lower bound barrier, we...

  17. Adaptive Space Structures

    Wada, B.

    1993-01-01

    The term adaptive structures refers to a structural control approach in which sensors, actuators, electronics, materials, structures, structural concepts, and system-performance-validation strategies are integrated to achieve specific objectives.

  18. Adaptive Spectral Doppler Estimation

    Gran, Fredrik; Jakobsson, Andreas; Jensen, Jørgen Arendt

    2009-01-01

    In this paper, 2 adaptive spectral estimation techniques are analyzed for spectral Doppler ultrasound. The purpose is to minimize the observation window needed to estimate the spectrogram to provide a better temporal resolution and gain more flexibility when designing the data acquisition sequence....... The methods can also provide better quality of the estimated power spectral density (PSD) of the blood signal. Adaptive spectral estimation techniques are known to pro- vide good spectral resolution and contrast even when the ob- servation window is very short. The 2 adaptive techniques are tested and...... compared with the averaged periodogram (Welch’s method). The blood power spectral capon (BPC) method is based on a standard minimum variance technique adapted to account for both averaging over slow-time and depth. The blood amplitude and phase estimation technique (BAPES) is based on finding a set of...

  19. Adaptive multiresolution methods

    Schneider Kai

    2011-12-01

    Full Text Available These lecture notes present adaptive multiresolution schemes for evolutionary PDEs in Cartesian geometries. The discretization schemes are based either on finite volume or finite difference schemes. The concept of multiresolution analyses, including Harten’s approach for point and cell averages, is described in some detail. Then the sparse point representation method is discussed. Different strategies for adaptive time-stepping, like local scale dependent time stepping and time step control, are presented. Numerous numerical examples in one, two and three space dimensions validate the adaptive schemes and illustrate the accuracy and the gain in computational efficiency in terms of CPU time and memory requirements. Another aspect, modeling of turbulent flows using multiresolution decompositions, the so-called Coherent Vortex Simulation approach is also described and examples are given for computations of three-dimensional weakly compressible mixing layers. Most of the material concerning applications to PDEs is assembled and adapted from previous publications [27, 31, 32, 34, 67, 69].

  20. Adaptive Heat Engine

    Allahverdyan, A. E.; Babajanyan, S. G.; Martirosyan, N. H.; Melkikh, A. V.

    2016-07-01

    A major limitation of many heat engines is that their functioning demands on-line control and/or an external fitting between the environmental parameters (e.g., temperatures of thermal baths) and internal parameters of the engine. We study a model for an adaptive heat engine, where—due to feedback from the functional part—the engine's structure adapts to given thermal baths. Hence, no on-line control and no external fitting are needed. The engine can employ unknown resources; it can also adapt to results of its own functioning that make the bath temperatures closer. We determine resources of adaptation and relate them to the prior information available about the environment.

  1. Adaptive Architectural Envelope

    Foged, Isak Worre; Kirkegaard, Poul Henning

    2010-01-01

    Recent years have seen an increasing variety of applications of adaptive architectural structures for improvement of structural performance by recognizing changes in their environments and loads, adapting to meet goals, and using past events to improve future performance or maintain serviceability....... The general scopes of this paper are to develop a new adaptive kinetic architectural structure, particularly a reconfigurable architectural structure which can transform body shape from planar geometries to hyper-surfaces using different control strategies, i.e. a transformation into more than one or...... two different shape alternatives. The adaptive structure is a proposal for a responsive building envelope which is an idea of a first level operational framework for present and future investigations towards performance based responsive architectures through a set of responsive typologies. A mock- up...

  2. Statistical Physics of Adaptation

    Perunov, Nikolai; England, Jeremy

    2014-01-01

    All living things exhibit adaptations that enable them to survive and reproduce in the natural environment that they inhabit. From a biological standpoint, it has long been understood that adaptation comes from natural selection, whereby maladapted individuals do not pass their traits effectively to future generations. However, we may also consider the phenomenon of adaptation from the standpoint of physics, and ask whether it is possible to delineate what the difference is in terms of physical properties between something that is well-adapted to its surrounding environment, and something that is not. In this work, we undertake to address this question from a theoretical standpoint. Building on past fundamental results in far-from-equilibrium statistical mechanics, we demonstrate a generalization of the Helmholtz free energy for the finite-time stochastic evolution of driven Newtonian matter. By analyzing this expression term by term, we are able to argue for a general tendency in driven many-particle systems...

  3. Adaptive trial designs.

    Lai, Tze Leung; Lavori, Philip William; Shih, Mei-Chiung

    2012-01-01

    We review adaptive designs for clinical trials, giving special attention to the control of the Type I error in late-phase confirmatory trials, when the trial planner wishes to adjust the final sample size of the study in response to an unblinded analysis of interim estimates of treatment effects. We point out that there is considerable inefficiency in using the adaptive designs that employ conditional power calculations to reestimate the sample size and that maintain the Type I error by using certain weighted test statistics. Although these adaptive designs have little advantage over familiar group-sequential designs, our review also describes recent developments in adaptive designs that are both flexible and efficient. We also discuss the use of Bayesian designs, when the context of use demands control over operating characteristics (Type I and II errors) and correction of the bias of estimated treatment effects. PMID:21838549

  4. Leak test adapter for containers

    Hallett, Brian H.; Hartley, Michael S.

    1996-01-01

    An adapter is provided for facilitating the charging of containers and leak testing penetration areas. The adapter comprises an adapter body and stem which are secured to the container's penetration areas. The container is then pressurized with a tracer gas. Manipulating the adapter stem installs a penetration plug allowing the adapter to be removed and the penetration to be leak tested with a mass spectrometer. Additionally, a method is provided for using the adapter.

  5. Frustratingly Easy Domain Adaptation

    Daumé, Hal

    2009-01-01

    We describe an approach to domain adaptation that is appropriate exactly in the case when one has enough ``target'' data to do slightly better than just using only ``source'' data. Our approach is incredibly simple, easy to implement as a preprocessing step (10 lines of Perl!) and outperforms state-of-the-art approaches on a range of datasets. Moreover, it is trivially extended to a multi-domain adaptation problem, where one has data from a variety of different domains.

  6. Adaptive quantum teleportation

    Modlawska, Joanna; Grudka, Andrzej

    2008-01-01

    We consider multiple teleportation in the Knill-Laflamme-Milburn (KLM) scheme. We introduce adaptive teleportation, i.e., such that the choice of entangled state used in the next teleportation depends on the results of the measurements performed during the previous teleportations. We show that adaptive teleportation enables an increase in the probability of faithful multiple teleportation in the KLM scheme. In particular if a qubit is to be teleported more than once then it is better to use n...

  7. The Adaptive Automation Design

    Calefato, Caterina; Montanari, Roberto; TESAURI, Francesco

    2008-01-01

    After considering the positive effects of adaptive automation implementation, this chapter focuses on two partly overlapping phenomena: on the one hand, the role of trust in automation is considered, particularly as to the effects of overtrust and mistrust in automation's reliability; on the other hand, long-term lack of exercise on specific operation may lead users to skill deterioration. As a future work, it will be interesting and challenging to explore the conjunction of adaptive automati...

  8. The genomics of adaptation

    Radwan, Jacek; Babik, Wiesław

    2012-01-01

    The amount and nature of genetic variation available to natural selection affect the rate, course and outcome of evolution. Consequently, the study of the genetic basis of adaptive evolutionary change has occupied biologists for decades, but progress has been hampered by the lack of resolution and the absence of a genome-level perspective. Technological advances in recent years should now allow us to answer many long-standing questions about the nature of adaptation. The data gathered so far ...

  9. Facilitation of CRISPR adaptation

    Abedon, Stephen T.

    2011-01-01

    CRISPR systems, as bacterial defenses against phages, logically must display in their functioning a sequence of at least three major steps. These, in order of occurrence, are “facilitation,” adaptation and interference, where the facilitation step is the main issue considered in this commentary. Interference is the blocking of phage infections as mediated in part by CRISPR spacer sequences. Adaptation, at least as narrowly defined, is the acquisition of these spacer sequences by CRISPR loci. ...

  10. Robust Adaptive Control

    Narendra, K. S.; Annaswamy, A. M.

    1985-01-01

    Several concepts and results in robust adaptive control are are discussed and is organized in three parts. The first part surveys existing algorithms. Different formulations of the problem and theoretical solutions that have been suggested are reviewed here. The second part contains new results related to the role of persistent excitation in robust adaptive systems and the use of hybrid control to improve robustness. In the third part promising new areas for future research are suggested which combine different approaches currently known.

  11. Climate Adaptation in Europe

    At the Conference of Parties in Copenhagen, Denmark, December 7-18, 2009 Change Magazine will present a special issue on 'Climate Adaptation in Europe'. The magazine contains articles on climate policy strategies in European countries and cross-border studies on climate change, articles on climate adaptation in the Alps, on water quality as a bottleneck for the agricultural sector, and drought in the mediterranean countries. How will member countries in the European Union tackle the climate crisis?.

  12. Network and adaptive sampling

    Chaudhuri, Arijit

    2014-01-01

    Combining the two statistical techniques of network sampling and adaptive sampling, this book illustrates the advantages of using them in tandem to effectively capture sparsely located elements in unknown pockets. It shows how network sampling is a reliable guide in capturing inaccessible entities through linked auxiliaries. The text also explores how adaptive sampling is strengthened in information content through subsidiary sampling with devices to mitigate unmanageable expanding sample sizes. Empirical data illustrates the applicability of both methods.

  13. Opportunistic Adaptation Knowledge Discovery

    Badra, Fadi; Cordier, Amélie; Lieber, Jean

    2009-01-01

    The original publication is available at www.springerlink.com International audience Adaptation has long been considered as the Achilles' heel of case-based reasoning since it requires some domain-specific knowledge that is difficult to acquire. In this paper, two strategies are combined in order to reduce the knowledge engineering cost induced by the adaptation knowledge (CA) acquisition task: CA is learned from the case base by the means of knowledge discovery techniques, and the CA a...

  14. Learning to Adapt. Organisational Adaptation to Climate Change Impacts

    Analysis of human adaptation to climate change should be based on realistic models of adaptive behaviour at the level of organisations and individuals. The paper sets out a framework for analysing adaptation to the direct and indirect impacts of climate change in business organisations with new evidence presented from empirical research into adaptation in nine case-study companies. It argues that adaptation to climate change has many similarities with processes of organisational learning. The paper suggests that business organisations face a number of obstacles in learning how to adapt to climate change impacts, especially in relation to the weakness and ambiguity of signals about climate change and the uncertainty about benefits flowing from adaptation measures. Organisations rarely adapt 'autonomously', since their adaptive behaviour is influenced by policy and market conditions, and draws on resources external to the organisation. The paper identifies four adaptation strategies that pattern organisational adaptive behaviour

  15. Adaptation and perceptual norms

    Webster, Michael A.; Yasuda, Maiko; Haber, Sara; Leonard, Deanne; Ballardini, Nicole

    2007-02-01

    We used adaptation to examine the relationship between perceptual norms--the stimuli observers describe as psychologically neutral, and response norms--the stimulus levels that leave visual sensitivity in a neutral or balanced state. Adapting to stimuli on opposite sides of a neutral point (e.g. redder or greener than white) biases appearance in opposite ways. Thus the adapting stimulus can be titrated to find the unique adapting level that does not bias appearance. We compared these response norms to subjectively defined neutral points both within the same observer (at different retinal eccentricities) and between observers. These comparisons were made for visual judgments of color, image focus, and human faces, stimuli that are very different and may depend on very different levels of processing, yet which share the property that for each there is a well defined and perceptually salient norm. In each case the adaptation aftereffects were consistent with an underlying sensitivity basis for the perceptual norm. Specifically, response norms were similar to and thus covaried with the perceptual norm, and under common adaptation differences between subjectively defined norms were reduced. These results are consistent with models of norm-based codes and suggest that these codes underlie an important link between visual coding and visual experience.

  16. Rapid contrast infusion of bolus injection for i. v. urography; Comparative density measurements of the renal collecting system during sequential CT. Kontrastmittel-Kurzinfusion oder -Bolusinjektion bei der i. v. Urographie; Vergleichende Dichtemessungen im Nierenbecken-Kelchsystem mit der Sequenz-Computertomographie

    Kaltenborn, H. (Institut fuer Klinische Strahlenkunde am Klinikum der Johannes-Gutenberg-Univ., Mainz (Germany)); Klose, P. (Institut fuer Klinische Strahlenkunde am Klinikum der Johannes-Gutenberg-Univ., Mainz (Germany)); Klose, K. (Institut fuer Klinische Strahlenkunde am Klinikum der Johannes-Gutenberg-Univ., Mainz (Germany)); Schmiedel, E. (Byk Gulden, Konstanz (Germany))

    1993-06-01

    The rate of contrast injection during i.v. urography may vary considerably (bolus injection or drip infusion). The effect of 5 rates of injection (6, 12, 18, 36 and 72 ml/min) on the contrast density in the renal collecting system was examined over a period of 30 minutes. Measurements showed an inter-individual difference of more than 200% in each group. The intra-individual variations for different rates of injection were very slight; individual concentration in the kidney for a given dose depends only slightly on the rate of injection. There is no statistically significant improvement in contrast values as a result of a bolus injection. The reduced incidence of side effects justifies the use of bolus injections but pressure injections are unnecessary from a diagnostic point view. (orig.)

  17. On Adaptive vs. Non-adaptive Security of Multiparty Protocols

    Canetti, Ran; Damgård, Ivan Bjerre; Dziembowski, Stefan; Ishai, Yuval; Malkin, Tal

    course of the computation. We study the relations between adaptive security (i.e., security in the adaptive setting) and non-adaptive security, according to two definitions and in several models of computation. While affirming some prevailing beliefs, we also obtain some unexpected results. Some...... definition of Canetti, for honest-but-curious adversaries, adaptive security is equivalent to non-adaptive security when the number of parties is logarithmic, and is strictly stronger than non-adaptive security when the number of parties is super-logarithmic. For Byzantine adversaries, adaptive security is...

  18. Solar Adaptive Optics

    Thomas R. Rimmele

    2011-06-01

    Full Text Available Adaptive optics (AO has become an indispensable tool at ground-based solar telescopes. AO enables the ground-based observer to overcome the adverse effects of atmospheric seeing and obtain diffraction limited observations. Over the last decade adaptive optics systems have been deployed at major ground-based solar telescopes and revitalized ground-based solar astronomy. The relatively small aperture of solar telescopes and the bright source make solar AO possible for visible wavelengths where the majority of solar observations are still performed. Solar AO systems enable diffraction limited observations of the Sun for a significant fraction of the available observing time at ground-based solar telescopes, which often have a larger aperture than equivalent space based observatories, such as HINODE. New ground breaking scientific results have been achieved with solar adaptive optics and this trend continues. New large aperture telescopes are currently being deployed or are under construction. With the aid of solar AO these telescopes will obtain observations of the highly structured and dynamic solar atmosphere with unprecedented resolution. This paper reviews solar adaptive optics techniques and summarizes the recent progress in the field of solar adaptive optics. An outlook to future solar AO developments, including a discussion of Multi-Conjugate AO (MCAO and Ground-Layer AO (GLAO will be given.

  19. Adaptation and risk management

    Preston, Benjamin L [ORNL

    2011-01-01

    Adaptation assessment methods are compatible with the international risk management standard ISO:31000. Risk management approaches are increasingly being recommended for adaptation assessments at both national and local levels. Two orientations to assessments can commonly be identified: top-down and bottom-up, and prescriptive and diagnostic. Combinations of these orientations favor different types of assessments. The choice of orientation can be related to uncertainties in prediction and taking action, in the type of adaptation and in the degree of system stress. Adopting multiple viewpoints is to be encouraged, especially in complex situations. The bulk of current guidance material is consistent with top-down and predictive approaches, thus is most suitable for risk scoping and identification. Abroad range ofmaterial fromwithin and beyond the climate change literature can be used to select methods to be used in assessing and implementing adaptation. The framing of risk, correct formulation of the questions being investigated and assessment methodology are critical aspects of the scoping phase. Only when these issues have been addressed should be issue of specific methods and tools be addressed. The reorientation of adaptation from an assessment focused solely on anthropogenic climate change to broader issues of vulnerability/resilience, sustainable development and disaster risk, especially through a risk management framework, can draw from existing policy and management understanding in communities, professions and agencies, incorporating existing agendas, knowledge, risks, and issues they already face.

  20. Decoupled Adapt-then-Combine diffusion networks with adaptive combiners

    Fernandez-Bes, Jesus; Arenas-García, Jerónimo; Silva, Magno T. M.; Azpicueta-Ruiz, Luis A.

    2015-01-01

    In this paper we analyze a novel diffusion strategy for adaptive networks called Decoupled Adapt-then-Combine, which keeps a fully local estimate of the solution for the adaptation step. Our strategy, which is specially convenient for heterogeneous networks, is compared with the standard Adapt-then-Combine scheme and theoretically analyzed using energy conservation arguments. Such comparison shows the need of implementing adaptive combiners for both schemes to obtain a good performance in cas...

  1. Evolution of adaptation mechanisms: Adaptation energy, stress, and oscillating death.

    Gorban, Alexander N; Tyukina, Tatiana A; Smirnova, Elena V; Pokidysheva, Lyudmila I

    2016-09-21

    In 1938, Selye proposed the notion of adaptation energy and published 'Experimental evidence supporting the conception of adaptation energy.' Adaptation of an animal to different factors appears as the spending of one resource. Adaptation energy is a hypothetical extensive quantity spent for adaptation. This term causes much debate when one takes it literally, as a physical quantity, i.e. a sort of energy. The controversial points of view impede the systematic use of the notion of adaptation energy despite experimental evidence. Nevertheless, the response to many harmful factors often has general non-specific form and we suggest that the mechanisms of physiological adaptation admit a very general and nonspecific description. We aim to demonstrate that Selye׳s adaptation energy is the cornerstone of the top-down approach to modelling of non-specific adaptation processes. We analyze Selye׳s axioms of adaptation energy together with Goldstone׳s modifications and propose a series of models for interpretation of these axioms. Adaptation energy is considered as an internal coordinate on the 'dominant path' in the model of adaptation. The phenomena of 'oscillating death' and 'oscillating remission' are predicted on the base of the dynamical models of adaptation. Natural selection plays a key role in the evolution of mechanisms of physiological adaptation. We use the fitness optimization approach to study of the distribution of resources for neutralization of harmful factors, during adaptation to a multifactor environment, and analyze the optimal strategies for different systems of factors. PMID:26801872

  2. Adaptive cancellation techniques

    1983-11-01

    An adaptive signal canceller has been evaluated for the enhancement of pulse signal reception during the transmission of a high power ECM jamming signal. The canceller design is based on the use of DRFM(Digital RF Memory) technology as part of an adaptive multiple tapped delay line. The study includes analysis of relationship of tap spacing and waveform bandwidth, survey of related documents in areas of sidelobe cancellers, transversal equalizers, and adaptive filters, and derivation of control equations and corresponding control processes. The simulation of overall processes included geometric analysis of the multibeam transmitting antenna, multiple reflection sources and the receiving antenna; waveforms, tap spacings and bandwidths; and alternate control algorithms. Conclusions are provided regarding practical system control algorithms, design characteristics and limitations.

  3. Adaptable Embedded Systems

    Lisbôa, Carlos; Carro, Luigi

    2013-01-01

    As embedded systems become more complex, designers face a number of challenges at different levels: they need to boost performance, while keeping energy consumption as low as possible, they need to reuse existent software code, and at the same time they need to take advantage of the extra logic available in the chip, represented by multiple processors working together.  This book describes several strategies to achieve such different and interrelated goals, by the use of adaptability. Coverage includes reconfigurable systems, dynamic optimization techniques such as binary translation and trace reuse, new memory architectures including homogeneous and heterogeneous multiprocessor systems, communication issues and NOCs, fault tolerance against fabrication defects and soft errors, and finally, how one can combine several of these techniques together to achieve higher levels of performance and adaptability.  The discussion also includes how to employ specialized software to improve this new adaptive system, and...

  4. Engineering Adaptive Web Applications

    Dolog, Peter

    2007-01-01

    Information and services on the web are accessible for everyone. Users of the web differ in their background, culture, political and social environment, interests and so on. Ambient intelligence was envisioned as a concept for systems which are able to adapt to user actions and needs....... With the growing amount of information and services, the web applications become natural candidates to adopt the concepts of ambient intelligence. Such applications can deal with divers user intentions and actions based on the user profile and can suggest the combination of information content and services which...... suit the user profile the most. This paper summarizes the domain engineering framework for such adaptive web applications. The framework provides guidelines to develop adaptive web applications as members of a family. It suggests how to utilize the design artifacts as knowledge which can be used...

  5. Adaptive Metric Kernel Regression

    Goutte, Cyril; Larsen, Jan

    1998-01-01

    Kernel smoothing is a widely used nonparametric pattern recognition technique. By nature, it suffers from the curse of dimensionality and is usually difficult to apply to high input dimensions. In this paper, we propose an algorithm that adapts the input metric used in multivariate regression by...... minimising a cross-validation estimate of the generalisation error. This allows one to automatically adjust the importance of different dimensions. The improvement in terms of modelling performance is illustrated on a variable selection task where the adaptive metric kernel clearly outperforms the standard...

  6. STUDYING COMPLEX ADAPTIVE SYSTEMS

    John H. Holland

    2006-01-01

    Complex adaptive systems (cas) - systems that involve many components that adapt or learn as they interact - are at the heart of important contemporary problems. The study of cas poses unique challenges: Some of our most powerful mathematical tools, particularly methods involving fixed points, attractors, and the like, are of limited help in understanding the development of cas. This paper suggests ways to modify research methods and tools, with an emphasis on the role of computer-based models, to increase our understanding of cas.

  7. Adaptive metric kernel regression

    Goutte, Cyril; Larsen, Jan

    2000-01-01

    Kernel smoothing is a widely used non-parametric pattern recognition technique. By nature, it suffers from the curse of dimensionality and is usually difficult to apply to high input dimensions. In this contribution, we propose an algorithm that adapts the input metric used in multivariate...... regression by minimising a cross-validation estimate of the generalisation error. This allows to automatically adjust the importance of different dimensions. The improvement in terms of modelling performance is illustrated on a variable selection task where the adaptive metric kernel clearly outperforms the...

  8. Adaptive radar resource management

    Moo, Peter

    2015-01-01

    Radar Resource Management (RRM) is vital for optimizing the performance of modern phased array radars, which are the primary sensor for aircraft, ships, and land platforms. Adaptive Radar Resource Management gives an introduction to radar resource management (RRM), presenting a clear overview of different approaches and techniques, making it very suitable for radar practitioners and researchers in industry and universities. Coverage includes: RRM's role in optimizing the performance of modern phased array radars The advantages of adaptivity in implementing RRMThe role that modelling and

  9. The Adaptability of Teams

    Jørgensen, Frances; Boer, Harry

    2006-01-01

    In this paper, data from a longitudinal case study in an organization attempting to adapt its internal work processes to changes in its external context are presented, analyzed and discussed. Specifically, functionally structured work teams in one department of a Danish production facility were...... proper alignment between the structuring of the work processes and characteristics of the external context (Lawrence & Lorsch, 1967) – it provides a unique opportunity to explore the adaptation process in practice. The paper contributes to the development of contingency theory by lending support to the...

  10. Adaptive heat engine

    Allahverdyan, A.E.; Babajanyan, S. G.; Martirosyan, N. H.; Melkikh, A. V.

    2016-01-01

    A major limitations for many heat engines is that their functioning demands on-line control, and/or an external fitting between environmental parameters (e.g. temperatures of thermal baths) and internal parameters of the engine. We study a model for an adaptive heat engine, where---due to feedback from the functional part---the engine's structure adapts to given thermal baths. Hence no on-line control and no external fitting are needed. The engine can employ unknown resources, it can also ada...

  11. Intestinal mucosal adaptation

    Laurie Drozdowski; Alan BR Thomson

    2006-01-01

    Intestinal failure is a condition characterized by malnutrition and/or dehydration as a result of the inadequate digestion and absorption of nutrients. The most common cause of intestinal failure is short bowel syndrome, which occurs when the functional gut mass is reduced below the level necessary for adequate nutrient and water absorption. This condition may be congenital, or may be acquired as a result of a massive resection of the small bowel. Following resection, the intestine is capable of adaptation in response to enteral nutrients as well as other trophic stimuli. Identifying factors that may enhance the process of intestinal adaptation is an exciting area of research with important potential clinical applications.

  12. How harmful are adaptation restrictions

    Bruin, de, B.; Dellink, R.B.

    2009-01-01

    The dominant assumption in economic models of climate policy remains that adaptation will be implemented in an optimal manner. There are, however, several reasons why optimal levels of adaptation may not be attainable. This paper investigates the effects of suboptimal levels of adaptation, i.e. adaptation restrictions, on the composition and level of climate change costs and on welfare. Several adaptation restrictions are identified and then simulated in a revised DICE model, extended with ad...

  13. Robust Optimal Adaptive Control Method with Large Adaptive Gain

    Nguyen, Nhan T.

    2009-01-01

    In the presence of large uncertainties, a control system needs to be able to adapt rapidly to regain performance. Fast adaptation is referred to the implementation of adaptive control with a large adaptive gain to reduce the tracking error rapidly. However, a large adaptive gain can lead to high-frequency oscillations which can adversely affect robustness of an adaptive control law. A new adaptive control modification is presented that can achieve robust adaptation with a large adaptive gain without incurring high-frequency oscillations as with the standard model-reference adaptive control. The modification is based on the minimization of the Y2 norm of the tracking error, which is formulated as an optimal control problem. The optimality condition is used to derive the modification using the gradient method. The optimal control modification results in a stable adaptation and allows a large adaptive gain to be used for better tracking while providing sufficient stability robustness. Simulations were conducted for a damaged generic transport aircraft with both standard adaptive control and the adaptive optimal control modification technique. The results demonstrate the effectiveness of the proposed modification in tracking a reference model while maintaining a sufficient time delay margin.

  14. Magnetic adaptive testing

    Tomáš, Ivan; Vértesy, G.

    Rijeka : INTECHWEB.ORG, 2012 - (Omar, M.), s. 145-184 ISBN 978-953-51-0108-6 R&D Projects: GA ČR GA101/09/1323 Institutional research plan: CEZ:AV0Z10100520 Keywords : ferromagnetic materials * nondestructive testing * steel * cast iron * industrial degradation * Magnetic Adaptive Testing Subject RIV: BM - Solid Matter Physics ; Magnetism

  15. Prism Adaptation in Schizophrenia

    Bigelow, Nirav O.; Turner, Beth M.; Andreasen, Nancy C.; Paulsen, Jane S.; O'Leary, Daniel S.; Ho, Beng-Choon

    2006-01-01

    The prism adaptation test examines procedural learning (PL) in which performance facilitation occurs with practice on tasks without the need for conscious awareness. Dynamic interactions between frontostriatal cortices, basal ganglia, and the cerebellum have been shown to play key roles in PL. Disruptions within these neural networks have also…

  16. Generalization of Prism Adaptation

    Redding, Gordon M.; Wallace, Benjamin

    2006-01-01

    Prism exposure produces 2 kinds of adaptive response. Recalibration is ordinary strategic remapping of spatially coded movement commands to rapidly reduce performance error. Realignment is the extraordinary process of transforming spatial maps to bring the origins of coordinate systems into correspondence. Realignment occurs when spatial…

  17. Adaptive municipal electronic forms

    Kuiper, Pieter; Dijk, van Betsy; Bondarouk, Tanya; Ruël, Huub; Guiderdoni-Jourdain, Karine; Oiry, Ewan

    2009-01-01

    Adaptation of electronic forms (e-forms) seems to be a step forward to reduce the burden for people who fill in forms. Municipalities more and more offer e-forms online that can be used by citizens to request a municipal product or service or by municipal employees to place a request on behalf of a

  18. Adaptive Computerized Instruction.

    Ray, Roger D.; And Others

    1995-01-01

    Describes an artificially intelligent multimedia computerized instruction system capable of developing a conceptual image of what a student is learning while the student is learning it. It focuses on principles of learning and adaptive behavioral control systems theory upon which the system is designed and demonstrates multiple user modes.…

  19. Robust Adaptive Structural Control

    Yang, Chi-Ming; Beck, James L.

    1995-01-01

    A new robust adaptive structural control design methodology is developed and presented which treats modeling uncertainties and limitations of control devices. Furthermore, no restriction is imposed on the structural models and the nature of the control devices so that the proposed method is very general. A simple linear single degree-of-freedom numerical example is presented to illustrate this approach.

  20. Adenosine in exercise adaptation.

    Simpson, R E; Phillis, J. W.

    1992-01-01

    By influencing the regulation of the mechanisms of angiogenesis, erythropoietin production, blood flow, myocardial glucose uptake, glycogenolysis, systolic blood pressure, respiration, plasma norepinephrine and epinephrine levels, adenosine may exert a significant effect on the body's adaptation response to exercise. However, adenosine's possible influence over the vasodilatory response to exercise in skeletal muscle is controversial and more research is required to resolve this issue. Variou...

  1. Adapting to Environmental Jolts.

    Meyer, Alan D.

    1982-01-01

    Examines the reactions of three San Francisco (California) hospitals to the 1975 doctors' strike. Analyzes the anticipatory, responsive, and readjustment phases of the hospitals' adaptations in terms of each hospital's previous market strategy, organizational structure and ideology, and deployment of slack resources, including financial, human,…

  2. ADAM: ADaptive Autonomous Machine

    Oosten, van Daan C.; Nijenhuis, Lucas F.J.; Bakkers, André W.P.; Vervoort, Wiek A.

    1996-01-01

    This paper describes a part of the development of an adaptive autonomous machine that is able to move in an unknown world extract knowledge out of the perceived data, has the possibility to reason, and finally has the capability to exchange experiences and knowledge with other agents. The agent is n

  3. Adaptation investments and homeownership

    Hansen, Jørgen Drud; Skak, Morten

    2008-01-01

    This article develops a model where ownership improves efficiency of the housing market as it enhances the utility of housing consumption for some consumers. The model is based on an extended Hotelling-Lancaster utility approach in which the ideal variant of housing is obtainable only by adapting...

  4. Unbiased Adaptive Expectation Schemes

    Antonio Palestrini; Mauro Gallegati

    2015-01-01

    There are situations in which the old-fashioned adaptive expectation process seems to provide a good description of agents' behavior (Chow, 2011). Unfortunately, this expectation scheme may not satisfy the necessary rationality condition (unconditional mean-zero error). This paper shows how to simply fix the problem introducing a bias correction term.

  5. Exploring Adaptive Program Behavior

    Bonnichsen, Lars Frydendal; Probst, Christian W.

    . Both solutions come at a cost; adaptivity issues a runtime overhead and requires more design effort, while dynamic recompilation takes time to perform. In this project, we plan to investigate the possibilities, limitations, and benefits of these techniques. This abstract covers our thoughts on how...

  6. Aging and dark adaptation.

    Jackson, G R; Owsley, C; McGwin, G

    1999-11-01

    Older adults have serious difficulty seeing under low illumination and at night, even in the absence of ocular disease. Optical changes in the aged eye, such as pupillary miosis and increased lens density, cannot account for the severity of this problem, and little is known about its neural basis. Dark adaptation functions were measured on 94 adults ranging in age from the 20s to the 80s to assess the rate of rod-mediated sensitivity recovery after exposure to a 98% bleach. Fundus photography and a grading scale were used to characterize macular health in subjects over age 49 in order to control for macular disease. Thresholds for each subject were corrected for lens density based on individual estimates, and pupil diameter was controlled. Results indicated that during human aging there is a dramatic slowing in rod-mediated dark adaptation that can be attributed to delayed rhodopsin regeneration. During the second component of the rod-mediated phase of dark adaptation, the rate of sensitivity recovery decreased 0.02 log unit/min per decade, and the time constant of rhodopsin regeneration increased 8.4 s/decade. The amount of time to reach within 0.3 log units of baseline scotopic sensitivity increased 2.76 min/decade. These aging-related changes in rod-mediated dark adaptation may contribute to night vision problems commonly experienced by the elderly. PMID:10748929

  7. Adaptive acoustooptic filter

    Psaltis, Demetri; Hong, John

    1984-01-01

    A new adaptive filter utilizing acoustooptic devices in a space integrating architecture is described. Two configurations are presented; one of them, suitable for signal estimation, is shown to approximate the Wiener filter, while the other, suitable for detection, is shown to approximate the matched filter.

  8. Transformational adaptation when incremental adaptations to climate change are insufficient.

    Kates, Robert W; Travis, William R; Wilbanks, Thomas J

    2012-05-01

    All human-environment systems adapt to climate and its natural variation. Adaptation to human-induced change in climate has largely been envisioned as increments of these adaptations intended to avoid disruptions of systems at their current locations. In some places, for some systems, however, vulnerabilities and risks may be so sizeable that they require transformational rather than incremental adaptations. Three classes of transformational adaptations are those that are adopted at a much larger scale, that are truly new to a particular region or resource system, and that transform places and shift locations. We illustrate these with examples drawn from Africa, Europe, and North America. Two conditions set the stage for transformational adaptation to climate change: large vulnerability in certain regions, populations, or resource systems; and severe climate change that overwhelms even robust human use systems. However, anticipatory transformational adaptation may be difficult to implement because of uncertainties about climate change risks and adaptation benefits, the high costs of transformational actions, and institutional and behavioral actions that tend to maintain existing resource systems and policies. Implementing transformational adaptation requires effort to initiate it and then to sustain the effort over time. In initiating transformational adaptation focusing events and multiple stresses are important, combined with local leadership. In sustaining transformational adaptation, it seems likely that supportive social contexts and the availability of acceptable options and resources for actions are key enabling factors. Early steps would include incorporating transformation adaptation into risk management and initiating research to expand the menu of innovative transformational adaptations. PMID:22509036

  9. Adaptation: Needs, Financing and Institutions

    Klein, Richard J.T.; Kartha, Sivan; Persson, Aasa; Watkiss, Paul; Ackerman, Frank; Downing, Thomas E.; Kjellen, Bo; Schipper, Lisa (Stockholm Environment Institute, Stockholm (SE))

    2008-07-01

    Regardless of the efforts put into mitigation, some impacts of climate change are already unavoidable. Adaptation to climate change has therefore become a key component of domestic climate policy, along with mitigation. Adaptation has also become key to the success of global climate policy. Without an agreement on supporting adaptation in developing countries, there will be no agreement on mitigation. Strong mitigation efforts make it more likely that adaptation will be effective and affordable. The world cannot rely on adaptation alone: it would eventually lead to a level of climate change to which adaptation is no longer feasible. Government action is needed to create an enabling environment for adaptation. This includes removing existing financial, legal, institutional and knowledge barriers to adaptation, and strengthening the capacity of people and organisations to adapt. The success of adaptation relies on the success of development, and vice versa. Poverty reduction, good governance, education, environmental protection, health and gender equality all contribute to adaptive capacity. Substantially more money is needed to support adaptation in developing countries. Current levels of funding will soon have to be scaled up by two orders of magnitude (from US$ hundreds of million to US$ tens of billion per year). An agreement on adaptation in Copenhagen in 2009 will need to include concrete steps towards a strengthened knowledge base for adaptation, substantially more funding for developing countries, and enhanced adaptation planning and implementation at the national level. Recommendations: Developed countries should accept a transparent, principle-based allocation of responsibility for adaptation funding, resulting in adequate, new and additional money to support adaptation programmes in developing countries. Levies on carbon market transactions and auctioning emission permits are two existing mechanisms of generating new and additional funds consistent with

  10. Cerebral hemodynamic changes measured by gradient-echo or spin-echo bolus tracking and its correlation to changes in ICA blood flow measured by phase-mapping MRI

    Marstrand, J.R.; Rostrup, Egill; Garde, Ellen; Larsson, Henrik B.W.

    2001-01-01

    Changes in cerebral blood flow (CBF) induced by Acetazolamide (ACZ) were measured using dynamic susceptibility contrast MRI (DSC-MRI) with both spin echo (SE) EPI and gradient echo (GE) EPI, and related to changes in internal carotid artery (ICA) flow measured by phase-mapping. Also examined was...... significant increase in CBF and CBV in response to ACZ, while SE-EPI measured a significant increase in CBV and MTT. CBV and MTT change measured by SE-EPI was sensitive to previous bolus injections. There was a significant linear relation between change in CBF measured by GE-EPI and change in ICA flow. In...... conclusion, GE-EPI under the present condition was superior to SE-EPI in monitoring cerebral vascular changes...

  11. Performance Comparison of Adaptive Algorithms for Adaptive line Enhancer

    Sanjeev Kumar Dhull; Sandeep K. Arya; O. P. Sahu

    2011-01-01

    We have designed and simulated an adaptive line enhancer system for conferencing. This system is based upon a least-mean-square (LMS) and recursive adaptive algorithm (RLS) Performance of ALE is compared for LMSandRLS algorithms.

  12. Adaptive versus non-adaptive strategies for quantum channel discrimination

    Harrow, Aram W.; Hassidim, Avinatan; Leung, Debbie W.; Watrous, John

    2009-01-01

    We provide a simple example that illustrates the advantage of adaptive over non-adaptive strategies for quantum channel discrimination. In particular, we give a pair of entanglement-breaking channels that can be perfectly discriminated by means of an adaptive strategy that requires just two channel evaluations, but for which no non-adaptive strategy can give a perfect discrimination using any finite number of channel evaluations.

  13. AdaptME toolkit : adaptation monitoring and evaluation

    Pringle, Patrick

    2011-01-01

    Organisations that have undertaken adaptation activities now face the challenge of evaluating what worked, what didn’t, how and why. This toolkit responds to a growing demand for practical support in evaluating adaptation progress and performance. AdaptME will help you to think through some of the factors that can make an evaluation of adaptation activities inherently challenging, and equip you to design a robust evaluation. You will be able to ‘tweak’ a single part of your evaluation des...

  14. The Alkali/Surfactant/ Polymer Process: Effects of Slug Size, Core Length and a Chase Polymer Le procédé alkali/surfactant/polymère : effets de la taille du bouchon, de la longueur de la carotte et d'un polymère de déplacement

    Green K. A.; Nasr-El-Din H. A.; Schramm L. L.

    2006-01-01

    An experimental study was conducted to examine the effects of slug size, core length, and a chase polymer on the effectiveness of the alkali/surfactant/polymer (A/S/P) process in recovering waterflood residual oil. Core flood experiments were conducted with unfired linear Berea sandstone cores. The tertiary oil recovery, oil cut, pressure drop, and chemical propagation were measured for each flood. Tertiary oil recovery significantly increased with the slug size up to 0. 5 of a pore volume. I...

  15. SpotADAPT

    Kaulakiene, Dalia; Thomsen, Christian; Pedersen, Torben Bach;

    2015-01-01

    Amazon Web Services (AWS). The users aiming for the spot market are presented with many instance types placed in multiple datacenters in the world, and thus it is difficult to choose the optimal deployment. In this paper, we propose the framework SpotADAPT (Spot-Aware (re-)Deployment of Analytical...... Processing Tasks) which is designed to help users by first, estimating the workload execution time on different AWS instance types, and, second, proposing the deployment (i.e., specific availability zone, instance type, pricing model) aligned with user-provided optimization goals (fastest or cheapest...... execution within boundaries). Moreover, during the execution of the workload, SpotADAPT suggests a redeployment if the current spot instance gets terminated by Amazon or a better deployment becomes possible due to fluctuations of the spot prices. The approach is evaluated using the actual execution times of...

  16. Unconsciously triggered conflict adaptation.

    Simon van Gaal

    Full Text Available In conflict tasks such as the Stroop, the Eriksen flanker or the Simon task, it is generally observed that the detection of conflict in the current trial reduces the impact of conflicting information in the subsequent trial; a phenomenon termed conflict adaptation. This higher-order cognitive control function has been assumed to be restricted to cases where conflict is experienced consciously. In the present experiment we manipulated the awareness of conflict-inducing stimuli in a metacontrast masking paradigm to directly test this assumption. Conflicting response tendencies were elicited either consciously (through primes that were weakly masked or unconsciously (strongly masked primes. We demonstrate trial-by-trial conflict adaptation effects after conscious as well as unconscious conflict, which could not be explained by direct stimulus/response repetitions. These findings show that unconscious information can have a longer-lasting influence on our behavior than previously thought and further stretch the functional boundaries of unconscious cognition.

  17. NEEDS - Information Adaptive System

    Kelly, W. L.; Benz, H. F.; Meredith, B. D.

    1980-01-01

    The Information Adaptive System (IAS) is an element of the NASA End-to-End Data System (NEEDS) Phase II and is focused toward onboard image processing. The IAS is a data preprocessing system which is closely coupled to the sensor system. Some of the functions planned for the IAS include sensor response nonuniformity correction, geometric correction, data set selection, data formatting, packetization, and adaptive system control. The inclusion of these sensor data preprocessing functions onboard the spacecraft will significantly improve the extraction of information from the sensor data in a timely and cost effective manner, and provide the opportunity to design sensor systems which can be reconfigured in near real-time for optimum performance. The purpose of this paper is to present the preliminary design of the IAS and the plans for its development.

  18. Adaptive manifold learning.

    Zhang, Zhenyue; Wang, Jing; Zha, Hongyuan

    2012-02-01

    Manifold learning algorithms seek to find a low-dimensional parameterization of high-dimensional data. They heavily rely on the notion of what can be considered as local, how accurately the manifold can be approximated locally, and, last but not least, how the local structures can be patched together to produce the global parameterization. In this paper, we develop algorithms that address two key issues in manifold learning: 1) the adaptive selection of the local neighborhood sizes when imposing a connectivity structure on the given set of high-dimensional data points and 2) the adaptive bias reduction in the local low-dimensional embedding by accounting for the variations in the curvature of the manifold as well as its interplay with the sampling density of the data set. We demonstrate the effectiveness of our methods for improving the performance of manifold learning algorithms using both synthetic and real-world data sets. PMID:21670485

  19. Adaptive Large Neighbourhood Search

    Røpke, Stefan

    Large neighborhood search is a metaheuristic that has gained popularity in recent years. The heuristic repeatedly moves from solution to solution by first partially destroying the solution and then repairing it. The best solution observed during this search is presented as the final solution. This...... tutorial introduces the large neighborhood search metaheuristic and the variant adaptive large neighborhood search that dynamically tunes parameters of the heuristic while it is running. Both heuristics belong to a broader class of heuristics that are searching a solution space using very large...... neighborhoods. The tutorial also present applications of the adaptive large neighborhood search, mostly related to vehicle routing problems for which the heuristic has been extremely successful. We discuss how the heuristic can be parallelized and thereby take advantage of modern desktop computers that...

  20. Adaptive semantics visualization

    Nazemi, Kawa

    2016-01-01

    This book introduces a novel approach for intelligent visualizations that adapts the different visual variables and data processing to human’s behavior and given tasks. Thereby a number of new algorithms and methods are introduced to satisfy the human need of information and knowledge and enable a usable and attractive way of information acquisition. Each method and algorithm is illustrated in a replicable way to enable the reproduction of the entire “SemaVis” system or parts of it. The introduced evaluation is scientifically well-designed and performed with more than enough participants to validate the benefits of the methods. Beside the introduced new approaches and algorithms, readers may find a sophisticated literature review in Information Visualization and Visual Analytics, Semantics and information extraction, and intelligent and adaptive systems. This book is based on an awarded and distinguished doctoral thesis in computer science.