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Sample records for boosting high-intensity focused

  1. High-intensity, focused ultrasonic fields

    DEFF Research Database (Denmark)

    Jensen, Leif Bjørnø

    1988-01-01

    machines marketed by companies in Germany and France, in particular. Two main types of ESWL systems are prevailing, the spark gap-based and the piezoelectric disk-based systems. This paper is introduced by a brief reconsideration of the features of pressure waves in water produced by an electrical...... distribution, etc. involving nonlinearity, diffraction, and absorption in the high-intensity focused ultrasonic fields produced by an ellipsoid as well as a spherical cap focusing geometry. Data from the development of an ESWL of the piezoelectric disk type are reported including demands to transducers...

  2. Final focus system for high intensity beams

    Directory of Open Access Journals (Sweden)

    Enrique Henestroza

    2005-05-01

    Full Text Available The neutralized transport experiment (NTX at the Heavy Ion Fusion Virtual National Laboratory is exploring the performance of neutralized final-focus systems for high perveance heavy ion beams. The final-focus scenario in a heavy ion fusion driver consists of several large aperture quadrupole magnets followed by a drift section in which the beam space charge is neutralized by a plasma. This beam is required to hit a millimeter-sized target spot at the end of the drift section. The objective of the NTX experiments and associated theory and simulations is to study the various physical mechanisms that determine the final spot size (radius r_{s} at a given distance (f from the end of the last quadrupole. In a fusion driver, f is the standoff distance required to keep the chamber wall and superconducting magnets properly protected. The NTX final quadrupole focusing system produces a converging beam at the entrance to the neutralized drift section where it focuses to a small spot. The final spot is determined by the conditions of the beam entering the quadrupole section, the beam dynamics in the magnetic lattice, and the plasma neutralization dynamics in the drift section. The main issues are the control of emittance growth due to high order fields from magnetic multipoles and image fields. In this paper, we will describe the theoretical and experimental aspects of the beam dynamics in the quadrupole lattice, and how these physical effects influence the final beam size. In particular, we present theoretical and experimental results on the dependence of final spot size on geometric aberrations and perveance.

  3. High-Intensity Focused Ultrasound Therapy: an Overview for Radiologists

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Sun; Rhim, Hyun Chul; Lim, Hyo Keun; Choi, Dong Il [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Choi, Min Joo [College of Medicine, Cheju National University, Jeju (Korea, Republic of)

    2008-08-15

    High-intensity focused ultrasound therapy is a novel, emerging, therapeutic modality that uses ultrasound waves, propagated through tissue media, as carriers of energy. This completely non-invasive technology has great potential for tumor ablation as well as hemostasis, thrombolysis and targeted drug/gene delivery. However, the application of this technology still has many drawbacks. It is expected that current obstacles to implementation will be resolved in the near future. In this review, we provide an overview of high-intensity focused ultrasound therapy from the basic physics to recent clinical studies with an interventional radiologist's perspective for the purpose of improving the general understanding of this cutting-edge technology as well as speculating on future developments

  4. Pulmonary Vein Isolation by High Intensity Focused Ultrasound

    Directory of Open Access Journals (Sweden)

    Matthias Antz

    2007-04-01

    Full Text Available Pulmonary vein isolation (PVI using radiofrequency current (RFC ablation is a potentially curative treatment option for patients with atrial fibrillation (AF. The shortcomings of the RFC technology (technically challenging, long procedure times, complications steadily kindle the interest in new energy sources and catheter designs. High intensity focused ultrasound (HIFU has the ability to precisely focus ultrasound waves in a defined area with a high energy density. HIFU balloon catheters (BC positioned at the PV ostia appear to be an ideal tool to transmit the ablation energy in a circumferential manner to the PV ostia and may therefore bear substantial advantage over conventional ablation catheters in PVI procedures. In clinical trials the HIFU BC has shown promising success rates similar to RFC catheter ablation for PVI in patients with AF. However, procedure times are still long and serious complications have been observed. Therefore, it may be a valuable alternative to the conventional techniques in selected patients but further clinical trials have to be initiated.

  5. Multifunctional pulse generator for high-intensity focused ultrasound system

    Science.gov (United States)

    Tamano, Satoshi; Yoshizawa, Shin; Umemura, Shin-Ichiro

    2017-07-01

    High-intensity focused ultrasound (HIFU) can achieve high spatial resolution for the treatment of diseases. A major technical challenge in implementing a HIFU therapeutic system is to generate high-voltage high-current signals for effectively exciting a multichannel HIFU transducer at high efficiencies. In this paper, we present the development of a multifunctional multichannel generator/driver. The generator can produce a long burst as well as an extremely high-voltage short pulse of pseudosinusoidal waves (trigger HIFU) and second-harmonic superimposed waves for HIFU transmission. The transmission timing, waveform, and frequency can be controlled using a field-programmable gate array (FPGA) via a universal serial bus (USB) microcontroller. The hardware is implemented in a compact printed circuit board. The test results of trigger HIFU reveal that the power consumption and the temperature rise of metal-oxide semiconductor field-effect transistors were reduced by 19.9% and 38.2 °C, respectively, from the previous design. The highly flexible performance of the novel generator/driver is demonstrated in the generation of second-harmonic superimposed waves, which is useful for cavitation-enhanced HIFU treatment, although the previous design exhibited difficulty in generating it.

  6. Robotic Assisted Laparoscopic Prostatectomy after High Intensity Focused Ultrasound Failure

    Directory of Open Access Journals (Sweden)

    Leon Telis

    2017-01-01

    Full Text Available Background. Prostate cancer is the most common cancer diagnosed in men. As new focal therapies become more popular in treatment of prostate cancer, failure cases requiring salvage therapy with either surgical or other techniques are being reported. Objective. To report the options in treatment of prostate cancer after recurrence or failure of the primary treatment modality. Methods. We report a salvage robotic assisted laparoscopic radical prostatectomy (RALP for prostate cancer recurrence following high intensity focused ultrasound treatment (HIFU in the United States. Results. A 67-year-old man who underwent HIFU treatment for prostate adenocarcinoma 2 years prior was presented with a rising prostate specific antigen of 6.1 ng/mL to our clinic. A biopsy proven recurrent disease in the area of previous treatment documented the failure of treatment. The patient elected to undergo a salvage RALP. The operation time was 159 minutes. The patient was discharged from the hospital on postoperative day 1 with no complications. The catheter was removed on post-op day 10. The patient reserved sexual function and urinary continence. The PSA levels on 6 months’ follow-up are undetectable. Conclusions. Salvage RALP is an effective and safe treatment choice for recurrent prostate adenocarcinoma following failed HIFU treatment if operated by an experienced surgeon.

  7. CT and Ultrasound Guided Stereotactic High Intensity Focused Ultrasound (HIFU)

    International Nuclear Information System (INIS)

    Wood, Bradford J.; Frenkel, V.; Viswanathan, A.; Dromi, S.; Oh, K.; Kam, A.; Li, K. C. P.; Yanof, J.; Bauer, C.; Kruecker, J.; Seip, R.

    2006-01-01

    To demonstrate the feasibility of CT and B-mode Ultrasound (US) targeted HIFU, a prototype coaxial focused ultrasound transducer was registered and integrated to a CT scanner. CT and diagnostic ultrasound were used for HIFU targeting and monitoring, with the goals of both thermal ablation and non-thermal enhanced drug delivery. A 1 megahertz coaxial ultrasound transducer was custom fabricated and attached to a passive position-sensing arm and an active six degree-of-freedom robotic arm via a CT stereotactic frame. The outer therapeutic transducer with a 10 cm fixed focal zone was coaxially mounted to an inner diagnostic US transducer (2-4 megahertz, Philips Medical Systems). This coaxial US transducer was connected to a modified commercial focused ultrasound generator (Focus Surgery, Indianapolis, IN) with a maximum total acoustic power of 100 watts. This pre-clinical paradigm was tested for ability to heat tissue in phantoms with monitoring and navigation from CT and live US. The feasibility of navigation via image fusion of CT with other modalities such as PET and MRI was demonstrated. Heated water phantoms were tested for correlation between CT numbers and temperature (for ablation monitoring). The prototype transducer and integrated CT/US imaging system enabled simultaneous multimodality imaging and therapy. Pre-clinical phantom models validated the treatment paradigm and demonstrated integrated multimodality guidance and treatment monitoring. Temperature changes during phantom cooling corresponded to CT number changes. Contrast enhanced or non-enhanced CT numbers may potentially be used to monitor thermal ablation with HIFU. Integrated CT, diagnostic US, and therapeutic focused ultrasound bridges a gap between diagnosis and therapy. Preliminary results show that the multimodality system may represent a relatively inexpensive, accessible, and simple method of both targeting and monitoring HIFU effects. Small animal pre-clinical models may be translated to large

  8. CT and Ultrasound Guided Stereotactic High Intensity Focused Ultrasound (HIFU)

    Science.gov (United States)

    Wood, Bradford J.; Yanof, J.; Frenkel, V.; Viswanathan, A.; Dromi, S.; Oh, K.; Kruecker, J.; Bauer, C.; Seip, R.; Kam, A.; Li, K. C. P.

    2006-05-01

    To demonstrate the feasibility of CT and B-mode Ultrasound (US) targeted HIFU, a prototype coaxial focused ultrasound transducer was registered and integrated to a CT scanner. CT and diagnostic ultrasound were used for HIFU targeting and monitoring, with the goals of both thermal ablation and non-thermal enhanced drug delivery. A 1 megahertz coaxial ultrasound transducer was custom fabricated and attached to a passive position-sensing arm and an active six degree-of-freedom robotic arm via a CT stereotactic frame. The outer therapeutic transducer with a 10 cm fixed focal zone was coaxially mounted to an inner diagnostic US transducer (2-4 megahertz, Philips Medical Systems). This coaxial US transducer was connected to a modified commercial focused ultrasound generator (Focus Surgery, Indianapolis, IN) with a maximum total acoustic power of 100 watts. This pre-clinical paradigm was tested for ability to heat tissue in phantoms with monitoring and navigation from CT and live US. The feasibility of navigation via image fusion of CT with other modalities such as PET and MRI was demonstrated. Heated water phantoms were tested for correlation between CT numbers and temperature (for ablation monitoring). The prototype transducer and integrated CT/US imaging system enabled simultaneous multimodality imaging and therapy. Pre-clinical phantom models validated the treatment paradigm and demonstrated integrated multimodality guidance and treatment monitoring. Temperature changes during phantom cooling corresponded to CT number changes. Contrast enhanced or non-enhanced CT numbers may potentially be used to monitor thermal ablation with HIFU. Integrated CT, diagnostic US, and therapeutic focused ultrasound bridges a gap between diagnosis and therapy. Preliminary results show that the multimodality system may represent a relatively inexpensive, accessible, and simple method of both targeting and monitoring HIFU effects. Small animal pre-clinical models may be translated to large

  9. [Transcranial focused ultrasound: Neurological applications of magnetic resonance-guided high-intensity focused ultrasound].

    Science.gov (United States)

    Werner, B; Martin, E

    2015-11-01

    Ultrasound surgery uses the thermal effects of the absorption of high-intensity focused ultrasound to induce localized thermal ablation of diseased tissue. The clinical introduction in recent years was made possible by a better understanding of the interactions of ultrasound with biological structures and the resulting physiological changes, major advances in the design of ultrasound applicators and the development of imaging modalities for reliable guiding the interventions. Magnetic resonance imaging-guided focused ultrasound surgery (MRgFUS) is especially appealing for applications in the brain where target volumes have to be accessed with high precision without inflicting collateral damage to surrounding healthy tissue. In 2013 a MRgFUS system was CE certified for the treatment of functional neurological disorders, such as chronic neuropathic pain and movement disorders. Currently, some 400 patients have been treated worldwide using this system, which is also undergoing clinical testing for the treatment of primary brain tumors and brain metastases. This article describes the technical basis of transcranial focused ultrasound neurosurgery and summarizes the current clinical experience of this new class of image-guided, non-invasive interventions.

  10. MRI-guided High-Intensity Focused Ultrasound of Breast Cancer

    NARCIS (Netherlands)

    Merckel, L.G.

    2014-01-01

    Magnetic resonance imaging-guided high-intensity focused ultrasound (MR-HIFU) is a promising technique for completely noninvasive tumor ablation. This thesis focuses on its application for the treatment of patients with breast cancer. The first part of the thesis describes the role of breast MRI for

  11. Bone metastasis treatment using magnetic resonance-guided high intensity focused ultrasound

    NARCIS (Netherlands)

    Yeo, Sin Yuin; Elevelt, Aaldert; Donato, Katia; van Rietbergen, Bert; ter Hoeve, Natalie D.; van Diest, Paul J.|info:eu-repo/dai/nl/075281775; Grüll, Holger

    2015-01-01

    Objectives: Bone pain resulting from cancer metastases reduces a patient's quality of life. Magnetic Resonance-guided High Intensity Focused Ultrasound (MR-HIFU) is a promising alternative palliative thermal treatment technique for bone metastases that has been tested in a few clinical studies.

  12. Dynamics of cavitation clouds within a high-intensity focused ultrasonic beam

    NARCIS (Netherlands)

    Lu, Yuan; Katz, Joseph; Prosperetti, Andrea

    2013-01-01

    In this experimental study, we generate a 500 kHz high-intensity focused ultrasonic beam, with pressure amplitude in the focal zone of up to 1.9 MPa, in initially quiescent water. The resulting pressure field and behavior of the cavitation bubbles are measured using high-speed digital in-line

  13. High Voltage Staircase Drive Circuit for Triggered High-Intensity Focused Ultrasound Treatment

    Science.gov (United States)

    Takada, Keisuke; Okada, Jumpei; Nakamura, Kotaro; Yoshizawa, Shin; Umemura, Shin-ichiro

    2012-07-01

    In triggered high-intensity focused ultrasound (HIFU) treatment, cavitation clouds are produced by extremely high intensity trigger pulses and enhance the effect of following heating waves. The ultrasound intensity must be quickly changed from that for trigger pulses to that for heating waves before cavitation clouds vanish. We newly designed and constructed a class D amplifier based on a staircase voltage drive concept, which has the capability of outputting high voltage waves for trigger pulses and continuous waves for heating waves and the capability of fast switching between the two modes. Its efficacy was confirmed by an experiment with a BSA containing polyacrylamide gel.

  14. Clinical applications for magnetic resonance guided high intensity focused ultrasound (MRgHIFU): present and future

    International Nuclear Information System (INIS)

    Ellis, Samatha; Rieke, Viola; Kohi, Maureen; Westphalen, Antonio C.

    2013-01-01

    It has been well known for decades that high intensity focused ultrasound (HIFU) generates heat in tissues resulting in coagulative necrosis. Implementation, however, has been slow, due to difficulties with finding an appropriate imaging modality that could not only guide treatment, but also provide real-time thermal feedback. These problems have been overcome with the newest magnetic resonance-guided high intensity focused ultrasound systems (MRgHIFU). With its superior spatial resolution enabling accurate image guidance coupled with its ability to provide real-time thermography during treatments, MRI is moving further into the realm of therapeutics for oncologic patient care. This article will discuss the implementation of an MR-guided HIFU system, current clinical indications and touch on future directions.

  15. Current status of high-intensity focused ultrasound for the management of uterine adenomyosis

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Vincent Y. T. [Dept. of Obstetrics and Gynaecology, Queen Mary Hospital, The University of Hong Kong, Hong Kong (China)

    2017-04-15

    While high-intensity focused ultrasound has been used for some time in the management of uterine fibroids, its effectiveness and safety in managing adenomyosis is less well established. A literature review was performed of all eligible reports using this modality as a treatment for adenomyosis. Relevant publications were obtained from the PubMed electronic database from inception through March 2016. Eleven articles, including information from 1,150 treatments and follow-up data from 990 patients, were reviewed. High-intensity focused ultrasound appears to be effective and safe in the management of symptomatic adenomyosis, and can be considered as an alternative uterine-sparing option for women with this condition.

  16. Magnetic resonance–guided interstitial high-intensity focused ultrasound for brain tumor ablation

    Science.gov (United States)

    MacDonell, Jacquelyn; Patel, Niravkumar; Rubino, Sebastian; Ghoshal, Goutam; Fischer, Gregory; Burdette, E. Clif; Hwang, Roy; Pilitsis, Julie G.

    2018-01-01

    Currently, treatment of brain tumors is limited to resection, chemotherapy, and radiotherapy. Thermal ablation has been recently explored. High-intensity focused ultrasound (HIFU) is being explored as an alternative. Specifically, the authors propose delivering HIFU internally to the tumor with an MRI-guided robotic assistant (MRgRA). The advantage of the authors’ interstitial device over external MRI-guided HIFU (MRgHIFU) is that it allows for conformal, precise ablation and concurrent tissue sampling. The authors describe their workflow for MRgRA HIFU delivery. PMID:29385926

  17. Application of Zernike polynomials towards accelerated adaptive focusing of transcranial high intensity focused ultrasound

    Science.gov (United States)

    Kaye, Elena A.; Hertzberg, Yoni; Marx, Michael; Werner, Beat; Navon, Gil; Levoy, Marc; Pauly, Kim Butts

    2012-01-01

    Purpose: To study the phase aberrations produced by human skulls during transcranial magnetic resonance imaging guided focused ultrasound surgery (MRgFUS), to demonstrate the potential of Zernike polynomials (ZPs) to accelerate the adaptive focusing process, and to investigate the benefits of using phase corrections obtained in previous studies to provide the initial guess for correction of a new data set. Methods: The five phase aberration data sets, analyzed here, were calculated based on preoperative computerized tomography (CT) images of the head obtained during previous transcranial MRgFUS treatments performed using a clinical prototype hemispherical transducer. The noniterative adaptive focusing algorithm [Larrat , “MR-guided adaptive focusing of ultrasound,” IEEE Trans. Ultrason. Ferroelectr. Freq. Control 57(8), 1734–1747 (2010)]10.1109/TUFFC.2010.1612 was modified by replacing Hadamard encoding with Zernike encoding. The algorithm was tested in simulations to correct the patients’ phase aberrations. MR acoustic radiation force imaging (MR-ARFI) was used to visualize the effect of the phase aberration correction on the focusing of a hemispherical transducer. In addition, two methods for constructing initial phase correction estimate based on previous patient's data were investigated. The benefits of the initial estimates in the Zernike-based algorithm were analyzed by measuring their effect on the ultrasound intensity at the focus and on the number of ZP modes necessary to achieve 90% of the intensity of the nonaberrated case. Results: Covariance of the pairs of the phase aberrations data sets showed high correlation between aberration data of several patients and suggested that subgroups can be based on level of correlation. Simulation of the Zernike-based algorithm demonstrated the overall greater correction effectiveness of the low modes of ZPs. The focal intensity achieves 90% of nonaberrated intensity using fewer than 170 modes of ZPs. The

  18. High-Intensity Focused Ultrasound for Pain Management in Patients with Cancer.

    Science.gov (United States)

    Dababou, Susan; Marrocchio, Cristina; Scipione, Roberto; Erasmus, Hans-Peter; Ghanouni, Pejman; Anzidei, Michele; Catalano, Carlo; Napoli, Alessandro

    2018-01-01

    Cancer-related pain affects up to 80% of patients with malignancies. Pain is an important distressing symptom that diminishes the quality of life and negatively affects the survival of patients. Opioid analgesics are generally the primary therapy for cancer-related pain, with surgery, radiation therapy, chemotherapy, and other interventions used in cases of treatment-resistant pain. These treatments, which can be associated with substantial side effects and systemic toxicity, may not be effective. High-intensity focused ultrasound is an entirely noninvasive technique that is approved for treatment of uterine fibroids, bone metastases, and essential tremors. With magnetic resonance imaging or ultrasonographic guidance, high-intensity ultrasound waves are focused on a small well-demarcated region to result in precise localized ablation. This treatment may represent a multimodality approach to treating patients with malignant diseases-facilitating pain palliation, enhanced local drug delivery and radiation therapy effects, and stimulation of anticancer specific immune responses, and potentially facilitating local tumor control. Focused ultrasound can be used to achieve pain palliation by producing several effects, including tissue denervation, tumor mass reduction, and neuromodulation, that can influence different pathways at the origin of the pain. This technology has several key advantages compared with other analgesic therapies: It is completely noninvasive, might be used to achieve rapid pain control, can be safely repeated, and can be used in combination with chemotherapy and radiation therapy to enhance their effects. Online supplemental material is available for this article. © RSNA, 2018.

  19. Transcostal high-intensity-focused ultrasound: ex vivo adaptive focusing feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Aubry, J-F; Pernot, M; Marquet, F; Tanter, M; Fink, M [Laboratoire Ondes et Acoustique, CNRS UMR 7587, Universite Paris VII, Inserm, ESPCI, 10 rue Vauquelin, 75005 Paris (France)], E-mail: jean-francois.aubry@espci.fr

    2008-06-07

    Ex vivo experiments have been conducted through excised pork rib with bone, cartilage, muscle and skin. The aberrating effect of the ribcage has been experimentally evaluated. Adaptive ultrasonic focusing through ribs has been studied at low power. Without any correction, the pressure fields in the focal plane were both affected by inhomogeneous attenuation and phase distortion and three main effects were observed: a mean 2 mm shift of the main lobe, a mean 1.25 mm spreading of the half width of the main lobe and up to 20 dB increase of the secondary lobe level. Thanks to time-reversal focusing, a 5 dB decrease in the secondary lobes was obtained and the ratio between the energy deposited at the target location and the total amount of energy emitted by the therapeutic array was six times higher than that without correction. Time-reversal minimizes the heating of the ribs by automatically sonicating between the ribs, as demonstrated by temperature measurements using thermocouples placed at different locations on the ribcage. It is also discussed how this aberration correction process could be achieved non-invasively for clinical application.

  20. Focusing of high intensity ultrasound through the rib cage using a therapeutic random phased array

    Science.gov (United States)

    Bobkova, Svetlana; Gavrilov, Leonid; Khokhlova, Vera; Shaw, Adam; Hand, Jeffrey; #, ||

    2010-01-01

    A method for focusing high intensity ultrasound through a rib cage that aims to minimize heating of the ribs whilst maintaining high intensities at the focus (or foci) is proposed and tested theoretically and experimentally. Two approaches, one based on geometric acoustics and the other accounting for diffraction effects associated with propagation through the rib cage, are investigated theoretically for idealized source conditions. It is shown that for an idealized radiator the diffraction approach provides a 23% gain in peak intensity and results in significantly less power losses on the ribs (1% versus 7.5% of the irradiated power) compared with the geometric one. A 2D 1-MHz phased array with 254 randomly distributed elements, tissue mimicking phantoms, and samples of porcine rib cages are used in experiments; the geometric approach is used to configure how the array is driven. Intensity distributions are measured in the plane of the ribs and in the focal plane using an infra-red camera. Theoretical and experimental results show that it is possible to provide adequate focusing through the ribs without overheating them for a single focus and several foci, including steering at ± 10–15 mm off and ± 20 mm along the array axis. Focus splitting due to the periodic spatial structure of ribs is demonstrated both in simulations and experiments; the parameters of splitting are quantified. The ability to produce thermal lesions with a split focal pattern in ex vivo porcine tissue placed beyond the rib phantom is also demonstrated. The results suggest that the method is potentially useful for clinical applications of HIFU for which the rib cage lies between the transducer(s) and the targeted tissue. PMID:20510186

  1. PRESAGE® as a new calibration method for high intensity focused ultrasound therapy

    Science.gov (United States)

    Costa, M.; McErlean, C.; Rivens, I.; Adamovics, J.; Leach, M. O.; ter Haar, G.; Doran, S. J.

    2015-01-01

    High Intensity Focused ultrasound (HIFU) is a non-invasive cancer therapy that makes use of the mainly thermal effects of ultrasound to destroy tissue. In order to achieve reliable treatment planning, it is necessary to characterise the ultrasound source (transducer) and to understand how the wave propagates in tissue and the energy deposition in the focal region. This novel exploratory study investigated how HIFU affects PRESAGE®, an optical phantom used for radiotherapy dosimetry, which is potentially a rapid method of calibrating the transducer. Samples, of two different formulations, were exposed to focused ultrasound and imaged using Optical Computed Tomography. First results showed that, PRESAGE® changes colour on ultrasound exposure (darker green regions were observed) with the alterations being related to the acoustic power and sample composition. Future work will involve quantification of these alterations and understanding how to relate them to the mechanisms of action of HIFU.

  2. MO-AB-210-03: Workshop [Advancements in high intensity focused ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Z. [University of Chicago (United States)

    2015-06-15

    The goal of this ultrasound hands-on workshop is to demonstrate advancements in high intensity focused ultrasound (HIFU) and to demonstrate quality control (QC) testing in diagnostic ultrasound. HIFU is a therapeutic modality that uses ultrasound waves as carriers of energy. HIFU is used to focus a beam of ultrasound energy into a small volume at specific target locations within the body. The focused beam causes localized high temperatures and produces a well-defined regions of necrosis. This completely non-invasive technology has great potential for tumor ablation and targeted drug delivery. At the workshop, attendees will see configurations, applications, and hands-on demonstrations with on-site instructors at separate stations. The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. At the workshop, an array of ultrasound testing phantoms and ultrasound scanners will be provided for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations of the techniques. Target audience: Medical physicists and other medical professionals in diagnostic imaging and radiation oncology with interest in high-intensity focused ultrasound and in diagnostic ultrasound QC. Learning Objectives: Learn ultrasound physics and safety for HIFU applications through live demonstrations Get an overview of the state-of-the art in HIFU technologies and equipment Gain familiarity with common elements of a quality control program for diagnostic ultrasound imaging Identify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools List of supporting vendors for HIFU and diagnostic ultrasound QC hands-on workshop: Philips Healthcare Alpinion Medical Systems Verasonics, Inc Zonare Medical Systems, Inc Computerized Imaging Reference Systems (CIRS), Inc. GAMMEX, Inc., Cablon Medical BV Steffen Sammet: NIH/NCI grant 5R25CA132822, NIH/NINDS grant 5R25NS

  3. A radiation emission shielding method for high intensity focus ultrasound probes.

    Science.gov (United States)

    Wu, Hao; Shen, Guofeng; Chen, Yazhu

    2015-01-01

    Electromagnetic compatibility (EMC) is a key issue in the design and development of safe and effective medical instruments. The treatment probes of high intensity focused ultrasound (HIFU) systems not only receive and transmit electromagnetic waves, but also radiate ultrasound waves, resulting in electromagnetic coupling. In this paper, an electromagnetic shielding method involving the enclosure of the probe in a copper wire mesh was introduced. First, sound pressure distribution simulations and measurements were performed using a hydrophone in order to evaluate the effects of the wire mesh on the acoustic performance of the HIFU system. The results indicated that the wire mesh did not disturb the normalized sound pressure field. In addition, the attenuation of the maximum pressure in the focal plane was equal to 6.2%. Then, the electronic emission level was tested in a chamber. After the implementation of the wire mesh, the 10-100 MHz frequency band radiation was suppressed, and the HIFU system satisfied the national EMC standards.

  4. High-Intensity Focused Ultrasound (HIFU) for the Treatment of Localized Prostate Cancer using Sonablate-500

    Science.gov (United States)

    Uchida, Toyoaki; Ohkusa, Hiroshi; Yamashita, Hideyuki; Nagata, Yoshihiro

    2005-03-01

    We evaluated 181 patients with localized prostate cancer treated with high-intensity focused ultrasound (HIFU) for biochemical disease-free rate, safety, morbidity and predictors of biochemical outcome. A total of 181 patients underwent HIFU with the Sonablate-500 and with at least 12 months of follow-up. Biochemical failure was defined according to the criteria recommended by the American Society for Therapeutic Radiology and Oncology Consensus Panel. The biochemical disease-free rates at 1, 3 and 5 years in all patients were 84%, 80% and 78%, respectively. The biochemical disease-free rates at 3 years for patients with pretreatment PSA less than 10 ng/ml, 10.01 to 20.0 ng/ml and more than 20.0 ng/ml were 94%, 75% and 35%, respectively (ppatients with localized prostate cancer, especially those with a pretreatment PSA level less than 20 ng/ml.

  5. A random phased array device for delivery of high intensity focused ultrasound

    International Nuclear Information System (INIS)

    Hand, J W; Shaw, A; Sadhoo, N; Rajagopal, S; Dickinson, R J; Gavrilov, L R

    2009-01-01

    Randomized phased arrays can offer electronic steering of a single focus and simultaneous multiple foci concomitant with low levels of secondary maxima and are potentially useful as sources of high intensity focused ultrasound (HIFU). This work describes laboratory testing of a 1 MHz random phased array consisting of 254 elements on a spherical shell of radius of curvature 130 mm and diameter 170 mm. Acoustic output power and efficiency are measured for a range of input electrical powers, and field distributions for various single- and multiple-focus conditions are evaluated by a novel technique using an infrared camera to provide rapid imaging of temperature changes on the surface of an absorbing target. Experimental results show that the array can steer a single focus laterally to at least ±15 mm off axis and axially to more than ±15 mm from the centre of curvature of the array and patterns of four and five simultaneous foci ±10 mm laterally and axially whilst maintaining low intensity levels in secondary maxima away from the targeted area in good agreement with linear theoretical predictions. Experiments in which pork meat was thermally ablated indicate that contiguous lesions several cm 3 in volume can be produced using the patterns of multiple foci.

  6. [Effects of high intensity focused ultrasound with SonoVue on blood vessels pathological examinations].

    Science.gov (United States)

    Qin, Yan; Bai, Jin; Li, Faqi; Wang, Zhibiao

    2010-12-01

    The injury of tumor blood vessels will break up the nutrition supply for the tumor. In this paper, we investigated the effects exerted by high intensity focused ultrasound (HIFU) combined with ultrasound microbubble agent on blood vessels. Ultrasound diagnosis was used to find the goat hepatic blood vessels each being approximately 3mm in diameter. HIFU was focused on the blood vessels. The acoustic power was 250W; HIFU irradiating Mode was line scan (the length of the line: 10 mm; speed: 3 mm/s; irradiating time: 30s). In the experimental group, 0.03 ml/kg SonoVue was injected into the goat before HIFU irradiation,while normal saline was given to the control group. The goats were killed at 24h after HIFU irradiation, then goat liver tissues and blood vessels of target area were taken out. HE staining and Victoria's blue and Ponceau's staining of tissue section showed that the endothelial cells of blood vessels dropped off and became necrosed, and the continuity of blood vessels was interrupted. HIFU combined with SonoVue will damage large blood vessels on HIFU focus, but there is no evident discrepancy between the group with SonoVue and the group without SonoVue.

  7. High-Intensity Focused Ultrasound (HIFU) in Uterine Fibroid Treatment: Review Study

    International Nuclear Information System (INIS)

    Mahmoud, Mustafa Z.; Alkhorayef, Mohammed; Alzimami, Khalid S.; Aljuhani, Manal Saud; Sulieman, Abdelmoneim

    2014-01-01

    High-intensity focused ultrasound (HIFU) is a highly precise medical procedure used locally to heat and destroy diseased tissue through ablation. This study intended to review HIFU in uterine fibroid therapy, to evaluate the role of HIFU in the therapy of leiomyomas as well as to review the actual clinical activities in this field including efficacy and safety measures beside the published clinical literature. An inclusive literature review was carried out in order to review the scientific foundation, and how it resulted in the development of extracorporeal distinct devices. Studies addressing HIFU in leiomyomas were identified from a search of the Internet scientific databases. The analysis of literature was limited to journal articles written in English and published between 2000 and 2013. In current gynecologic oncology, HIFU is used clinically in the treatment of leiomyomas. Clinical research on HIFU therapy for leiomyomas began in the 1990s, and the majority of patients with leiomyomas were treated predominantly with HIFUNIT 9000 and prototype single focus ultrasound devices. HIFU is a non-invasive and highly effective standard treatment with a large indication range for all sizes of leiomyomas, associated with high efficacy, low operative morbidity and no systemic side effects. Uterine fibroid treatment using HIFU was effective and safe in treating symptomatic uterine fibroids. Few studies are available in the literature regarding uterine artery embolization (UAE). HIFU provides an excellent option to treat uterine fibroids

  8. [Study on therapeutic dosimetry and biologic effect of high intensity focused ultrasound].

    Science.gov (United States)

    He, Xuemei; Xiong, Xin; Zou, Jianzhong; Li, Faqi; Ma, Ping; Wang, Zhibiao

    2009-02-01

    This study was aimed at exploring the high intensity focused ultrasound(HIFU) therapeutic dosimetry and its biologic effect. In-vitro, bovine liver was immersed into 0.9% NS and degassed for application. The JC Model-focused ultrasound tumor therapeutic system was used in the experiment. The HIFU parameters were: frequency 1.6 MHz, depth 20 mm, acoustic power from 16.44 W to 196.32 W. Under each power, at radiating times from is to 20 s, bioptic specimens were obtained from all samples. The results showed when the acoustic power was equal to or higher than 179.96 W, only is of radiating is adequate to induce coagulative necrosis, and when the acoustic power was lower than 65.44 W, the radiating time to produce coagulative necrosis was about 7 s. In the range of 65.44-179.96 W, at each time when the acoustic power was set up with an increment of 16.36 W, the time to produce coagulative necrosis was 1-2 s shorter. The form of biological focal region (BFR) varied with the acoustic power and HIFU irradiation time. The size of BFR increased with the increase of HIFU irradiation dosage (acoustic power x exposure time). There is positive correlation between the size of BFR and the dosage of HIFU irradiation (y = 0.0164x(1.05591), R5 = 0.9238, P < 0.05).

  9. Controlled tissue emulsification produced by high intensity focused ultrasound shock waves and millisecond boiling.

    Science.gov (United States)

    Khokhlova, Tatiana D; Canney, Michael S; Khokhlova, Vera A; Sapozhnikov, Oleg A; Crum, Lawrence A; Bailey, Michael R

    2011-11-01

    In high intensity focused ultrasound (HIFU) applications, tissue may be thermally necrosed by heating, emulsified by cavitation, or, as was recently discovered, emulsified using repetitive millisecond boiling caused by shock wave heating. Here, this last approach was further investigated. Experiments were performed in transparent gels and ex vivo bovine heart tissue using 1, 2, and 3 MHz focused transducers and different pulsing schemes in which the pressure, duty factor, and pulse duration were varied. A previously developed derating procedure to determine in situ shock amplitudes and the time-to-boil was refined. Treatments were monitored using B-mode ultrasound. Both inertial cavitation and boiling were observed during exposures, but emulsification occurred only when shocks and boiling were present. Emulsified lesions without thermal denaturation were produced with shock amplitudes sufficient to induce boiling in less than 20 ms, duty factors of less than 0.02, and pulse lengths shorter than 30 ms. Higher duty factors or longer pulses produced varying degrees of thermal denaturation combined with mechanical emulsification. Larger lesions were obtained using lower ultrasound frequencies. The results show that shock wave heating and millisecond boiling is an effective and reliable way to emulsify tissue while monitoring the treatment with ultrasound.

  10. Simulation of high-intensity focused ultrasound lesions in presence of boiling.

    Science.gov (United States)

    Grisey, Anthony; Yon, Sylvain; Letort, Véronique; Lafitte, Pauline

    2016-01-01

    The lesions induced by high-intensity focused ultrasound (HIFU) thermal ablations are particularly difficult to simulate due to the complexity of the involved phenomena. In particular, boiling has a strong influence on the lesion shape. Thus, it must be accounted for if it happens during the pulses to be modeled. However, no acoustic model enables the simulation of the resulting wave scattering. Therefore, we propose an equivalent model for the heat deposition pattern in the presence of boiling. Firstly, the acoustic field is simulated with k-Wave and the heat source term is calculated. Then, a thermal model is designed, including the equivalent model for boiling. It is rigorously calibrated and validated through the use of diversified ex vivo and in vivo data, including usually unexploited data types related to the bubble clouds. The proposed model enabled to efficiently simulate unitary pulses properties, including the sizes of the lesions, their morphology, the boiling onset time, and the influence of the boiling onset time on the lesions sizes. In this article, the whole procedure of model design, calibration, and validation is discussed. In addition to depicting the creative use of data, our modeling approach focuses on the understanding of the mechanisms influencing the shape of the lesion. Further work is required to study the influence of the remaining bubble clouds in the context of pulse groups.

  11. Motion compensation with skin contact control for high intensity focused ultrasound surgery in moving organs

    Science.gov (United States)

    Diodato, A.; Cafarelli, A.; Schiappacasse, A.; Tognarelli, S.; Ciuti, G.; Menciassi, A.

    2018-02-01

    High intensity focused ultrasound (HIFU) is an emerging therapeutic solution that enables non-invasive treatment of several pathologies, mainly in oncology. On the other hand, accurate targeting of moving abdominal organs (e.g. liver, kidney, pancreas) is still an open challenge. This paper proposes a novel method to compensate the physiological respiratory motion of organs during HIFU procedures, by exploiting a robotic platform for ultrasound-guided HIFU surgery provided with a therapeutic annular phased array transducer. The proposed method enables us to keep the same contact point between the transducer and the patient’s skin during the whole procedure, thus minimizing the modification of the acoustic window during the breathing phases. The motion of the target point is compensated through the rotation of the transducer around a virtual pivot point, while the focal depth is continuously adjusted thanks to the axial electronically steering capabilities of the HIFU transducer. The feasibility of the angular motion compensation strategy has been demonstrated in a simulated respiratory-induced organ motion environment. Based on the experimental results, the proposed method appears to be significantly accurate (i.e. the maximum compensation error is always under 1 mm), thus paving the way for the potential use of this technique for in vivo treatment of moving organs, and therefore enabling a wide use of HIFU in clinics.

  12. First Experience Of Application Of High-Intensity Focused Ultrasonic Ablation (Hifu In Prostate Cancer Treatment

    Directory of Open Access Journals (Sweden)

    A.V. Stativko

    2009-12-01

    Full Text Available The scientific article points out that 40 sessions of HIFU prostate ablation have been performed for estimation of clinical efficiency. Average frequency of influences presents 628±164 impulses; average volume of tissues subjected to influence during one procedure is 33,8±16,3 smi (132 % of prostate volume; average operation time constitutes 150 minutes (from 90 to 200 minutes. During the operation no complications have been occurred. In the first days after the session of HIFU there was a peak of PSA increase and then during 1,5-3 months there was decrease to the lowest index. Minimal PSA level was reached in 10-12 weeks after treatment and it constituted from 0,04 till 1,1 ngml depending on the disease state. Reduction of prostate volume occurred in average from the 30th day of postoperative period and lasted for 6 months, reaching in average 50 % from initial volume. Postoperative period varied from 10 till 16 days and constituted in average 12±0,8 days. Thus application of high-intensity focused ultrasonic ablation allows treating successfully various stages of prostate cancer with minimal number of side-effects and makes possible the early estimation of treatment efficiency

  13. Treatment of murine tumors using acoustic droplet vaporization-enhanced high intensity focused ultrasound

    International Nuclear Information System (INIS)

    Zhu Meili; Zhang Aili; Xu, Lisa X; Jiang Lixing; Fabiilli, Mario L; Fowlkes, J Brian

    2013-01-01

    High intensity focused ultrasound (HIFU) can be applied focally and noninvasively to thermally ablate solid tumors. Long treatment times are typically required for large tumors, which can expose patients to certain risks while potentially decreasing the therapeutic efficacy of the treatment. Acoustic droplet vaporization (ADV) is a promising modality that can enhance the efficacy of tumor treatment using HIFU. In this study, the therapeutic effects of combined HIFU and ADV was evaluated in mice bearing subcutaneously-implanted 4T1 tumors. Histological examination showed that the combination of HIFU and ADV generated a mean necrotic area in the tumor that was 2.9-fold larger than with HIFU alone. A significant enhancement of necrosis was found in the periphery of the tumor, where the blood supply was abundant. Seven days after treatment, the tumors treated with combined HIFU and ADV were 30-fold smaller in volume than tumors treated with HIFU alone. The study demonstrates the potential advantage of combining HIFU and ADV in tumor treatment. (paper)

  14. Measurement and numerical simulation of high intensity focused ultrasound field in water

    Science.gov (United States)

    Lee, Kang Il

    2017-11-01

    In the present study, the acoustic field of a high intensity focused ultrasound (HIFU) transducer in water was measured by using a commercially available needle hydrophone intended for HIFU use. To validate the results of hydrophone measurements, numerical simulations of HIFU fields were performed by integrating the axisymmetric Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation from the frequency-domain perspective with the help of a MATLAB-based software package developed for HIFU simulation. Quantitative values for the focal waveforms, the peak pressures, and the size of the focal spot were obtained in various regimes of linear, quasilinear, and nonlinear propagation up to the source pressure levels when the shock front was formed in the waveform. The numerical results with the HIFU simulator solving the KZK equation were compared with the experimental data and found to be in good agreement. This confirms that the numerical simulation based on the KZK equation is capable of capturing the nonlinear pressure field of therapeutic HIFU transducers well enough to make it suitable for HIFU treatment planning.

  15. PATHOMORPHISM OF PROSTATE CANCER DURING HIGH-INTENSITY FOCUSED ULTRASOUND TREATMENT

    Directory of Open Access Journals (Sweden)

    R. N. Fomkin

    2014-07-01

    Full Text Available The purpose of the study was to evaluate the efficiency of prostate cancer (PC treatment using high-intensity focused ultrasound (HIFU on the basis of morphometric and immunohistochemical (IHC analyses of postoperative prostate biopsy specimens. The study subjects were 40 patients with localized and locally advanced PC. The postoperative morphological analysis was made on the basis of standard hematoxylineosin staining and morphometric and IHC studies using the following antibodies: PCNA, Bcl-2, AMACR, Е-cadherin, and ANDR (Dako. Pre- and post-HIFU therapy histological examination of the routinely hematoxylin-eosin-stained specimens showed that the therapeutic pathomorphism of the tumor corresponded to grades III and IV. It was established that the IHC study should be used as an additional crite-rion for the efficiency of PC therapy after HIFU ablation. In spite of positive clinical, laboratory, instrumental, and objective changes, the patients with high AMACR and Bcl-2 levels and decreased Е-cadherin expression may be considered as a group at risk for prolonged malignant growth or recurrent PC.

  16. Feasibility study on photoacoustic guidance for high-intensity focused ultrasound-induced hemostasis

    Science.gov (United States)

    Nguyen, Van Phuc; Kim, Jeehyun; Ha, Kang-lyeol; Oh, Junghwan; Kang, Hyun Wook

    2014-10-01

    The feasibility of photoacoustic imaging (PAI) application was evaluated to map punctured blood vessels thermally treated by high-intensity focused ultrasound (HIFU) for hemostasis. A single-element HIFU transducer with a central frequency of 2.0 MHz, was used to induce thermal hemostasis on the punctured arteries. The HIFU-treated lesion was imaged and localized by high-contrast PAI guidance. The results showed that complete hemostasis was achieved after treatment of the damaged blood vessels within 25 to 52 s at the acoustic intensity of 3600 W/cm2. The coagulation time for the animal artery was ˜20% longer than that of the phantom possibly due to a lower Young's modulus. The reconstructed PA images were able to distinguish the treated area from the surrounding tissue in terms of augmented signal amplitudes (up to three times). Spectroscopic studies demonstrated that the optimal imaging wavelength was found to be 700 nm in order to reconstruct high-contrast photoacoustic images on HIFU-treated lesions. The proposed PAI integrated with HIFU treatment can be a feasible application to obtain safe and rapid hemostasis for acute arterial bleeding.

  17. Noninvasive body sculpting technologies with an emphasis on high-intensity focused ultrasound.

    Science.gov (United States)

    Jewell, Mark L; Solish, Nowell J; Desilets, Charles S

    2011-10-01

    Body-sculpting procedures are becoming increasingly popular in the United States. Although surgical lipoplasty remains the most common body sculpting procedure, a demand exists for noninvasive alternatives capable of reducing focal adiposity without the risks of adverse events (AEs) associated with invasive excisional body-sculpting procedures. This report describes the mechanism of action, efficacy, safety, and tolerability of cryolipolysis, radiofrequency ablation, low-level external laser therapy, injection lipolysis, low-intensity nonthermal ultrasound, and high-intensity focused ultrasound (HIFU), with an emphasis on thermal HIFU. The articles cited were identified via a PubMed search, with additional article citations identified by manual searching of the reference lists of articles identified through the literature search. Each of the noninvasive treatments reviewed can be administered on an outpatient basis. These treatments generally have fewer complications than lipoplasty and require little or no anesthesia or analgesia. However, HIFU is the only treatment that can produce significant results in a single treatment, and only radiofrequency, low-level laser therapy, and cryolipolysis have been approved for use in the United States. Early clinical data on HIFU support its efficacy and safety for body sculpting. In contrast, radiofrequency, laser therapy, and injection lipolysis have been associated with significant AEs. The published literature suggests that noninvasive body-sculpting techniques such as radiofrequency ablation, cryolipolysis, external low-level lasers, laser ablation, nonthermal ultrasound, and HIFU may be appropriate options for nonobese patients requiring modest reduction of adipose tissue.

  18. Ultrasound-guided high-intensity focused ultrasound treatment for abdominal wall endometriosis: Preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Wang Yang [Department of Ultrasound, Chinese PLA General Hospital, 28 Fuxing Road, Beijing 100853 (China); Wang Wei, E-mail: wangyang301301@yahoo.com.cn [Department of Ultrasound, Chinese PLA General Hospital, 28 Fuxing Road, Beijing 100853 (China); Wang Longxia; Wang Junyan; Tang Jie [Department of Ultrasound, Chinese PLA General Hospital, 28 Fuxing Road, Beijing 100853 (China)

    2011-07-15

    Purpose: To evaluate the safety and therapeutic efficacy of ultrasound (US)-guided high-intensity focused ultrasound (HIFU) ablation for the treatment of abdominal wall endometriosis (AWE). Materials and methods: Twenty-one consecutive patients with AWE were treated as outpatients by US-guided HIFU ablation under conscious sedation. The median size of the AWE was 2.4 cm (range 1.0-5.3 cm). An acoustic power of 200-420 W was used, intermittent HIFU exposure of 1 s was applied. Treatment was considered complete when the entire nodule and its nearby 1 cm margin become hyperechoic on US. Pain relief after HIFU ablation was observed and the treated nodule received serial US examinations during follow-up. Results: All AWE was successfully ablated after one session of HIFU ablation, the ablation time lasted for 5-48 min (median 13 min), no major complications occurred. The cyclic pain disappeared in all patients during a mean follow-up of 18.7 months (range 3-31 months). The treated nodules gradually shank over time, 16 nodules became unnoticeable on US during follow-up. Conclusion: US-guided HIFU ablation appears to be safe and effective for the treatment of AWE.

  19. High-Intensity Focused Ultrasound Circular Cyclocoagulation in Glaucoma: A Step Forward for Cyclodestruction?

    Directory of Open Access Journals (Sweden)

    Rodolfo Mastropasqua

    2017-01-01

    Full Text Available The ciliary body ablation is still considered as a last resort treatment to reduce the intraocular pressure (IOP in uncontrolled glaucoma. Several ablation techniques have been proposed over the years, all presenting a high rate of complications, nonselectivity for the target organ, and unpredictable dose-effect relationship. These drawbacks limited the application of cyclodestructive procedures almost exclusively to refractory glaucoma. High-intensity focused ultrasound (HIFU, proposed in the early 1980s and later abandoned because of the complexity and side effects of the procedure, was recently reconsidered in a new approach to destroy the ciliary body. Ultrasound circular cyclocoagulation (UC3, by using miniaturized transducers embedded in a dedicated circular-shaped device, permits to selectively treat the ciliary body in a one-step, computer-assisted, and non-operator-dependent procedure. UC3 shows a high level of safety along with a predictable and sustained IOP reduction in patients with refractory glaucoma. Because of this, the indication of UC3 was recently extended also to naïve-to-surgery patients, thus reconsidering the role and timing of ciliary body ablation in the surgical management of glaucoma. This article provides a review of the most used cycloablative techniques with particular attention to UC3, summarizing the current knowledge about this procedure and future possible developments.

  20. High intensity focused ultrasound technology, its scope and applications in therapy and drug delivery.

    Science.gov (United States)

    Phenix, Christopher Peter; Togtema, Melissa; Pichardo, Samuel; Zehbe, Ingeborg; Curiel, Laura

    2014-01-01

    Ultrasonography is a safe, inexpensive and wide-spread diagnostic tool capable of producing real-time non-invasive images without significant biological effects. However, the propagation of higher energy, intensity and frequency ultrasound waves through living tissues can induce thermal, mechanical and chemical effects useful for a variety of therapeutic applications. With the recent development of clinically approved High Intensity Focused Ultrasound (HIFU) systems, therapeutic ultrasound is now a medical reality. Indeed, HIFU has been used for the thermal ablation of pathological lesions; localized, minimally invasive ultrasound-mediated drug delivery through the transient formation of pores on cell membranes; the temporary disruption of skin and the blood brain barrier; the ultrasound induced break-down of blood clots; and the targeted release of drugs using ultrasound and temperature sensitive drug carriers. This review seeks to engage the pharmaceutical research community by providing an overview on the biological effects of ultrasound as well as highlighting important therapeutic applications, current deficiencies and future directions.

  1. Deep tissue penetration of nanoparticles using pulsed-high intensity focused ultrasound

    Science.gov (United States)

    You, Dong Gil; Yoon, Hong Yeol; Jeon, Sangmin; Um, Wooram; Son, Sejin; Park, Jae Hyung; Kwon, Ick Chan; Kim, Kwangmeyung

    2017-11-01

    Recently, ultrasound (US)-based drug delivery strategies have received attention to improve enhanced permeation and retention (EPR) effect-based passive targeting efficiency of nanoparticles in vitro and in vivo conditions. Among the US treatment techniques, pulsed-high intensity focused ultrasound (pHIFU) have specialized for improving tissue penetration of various macromolecules and nanoparticles without irreversible tissue damages. In this study, we have demonstrated that pHIFU could be utilized to improve tissue penetration of fluorescent dye-labeled glycol chitosan nanoparticles (FCNPs) in femoral tissue of mice. pHIFU could improve blood flow of the targeted-blood vessel in femoral tissue. In addition, tissue penetration of FCNPs was specifically increased 5.7-, 8- and 9.3-folds than that of non-treated (0 W pHIFU) femoral tissue, when the femoral tissue was treated with 10, 20 and 50 W of pHIFU, respectively. However, tissue penetration of FCNPs was significantly reduced after 3 h post-pHIFU treatment (50 W). Because overdose (50 W) of pHIFU led to irreversible tissue damages, including the edema and chapped red blood cells. These overall results support that pHIFU treatment can enhance the extravasation and tissue penetration of FCNPs as well as induce irreversible tissue damages. We expect that our results can provide advantages to optimize pHIFU-mediated delivery strategy of nanoparticles for further clinical applications.

  2. Dynamic T2-mapping during magnetic resonance guided high intensity focused ultrasound ablation of bone marrow

    Science.gov (United States)

    Waspe, Adam C.; Looi, Thomas; Mougenot, Charles; Amaral, Joao; Temple, Michael; Sivaloganathan, Siv; Drake, James M.

    2012-11-01

    Focal bone tumor treatments include amputation, limb-sparing surgical excision with bone reconstruction, and high-dose external-beam radiation therapy. Magnetic resonance guided high intensity focused ultrasound (MR-HIFU) is an effective non-invasive thermotherapy for palliative management of bone metastases pain. MR thermometry (MRT) measures the proton resonance frequency shift (PRFS) of water molecules and produces accurate (<1°C) and dynamic (<5s) thermal maps in soft tissues. PRFS-MRT is ineffective in fatty tissues such as yellow bone marrow and, since accurate temperature measurements are required in the bone to ensure adequate thermal dose, MR-HIFU is not indicated for primary bone tumor treatments. Magnetic relaxation times are sensitive to lipid temperature and we hypothesize that bone marrow temperature can be determined accurately by measuring changes in T2, since T2 increases linearly in fat during heating. T2-mapping using dual echo times during a dynamic turbo spin-echo pulse sequence enabled rapid measurement of T2. Calibration of T2-based thermal maps involved heating the marrow in a bovine femur and simultaneously measuring T2 and temperature with a thermocouple. A positive T2 temperature dependence in bone marrow of 20 ms/°C was observed. Dynamic T2-mapping should enable accurate temperature monitoring during MR-HIFU treatment of bone marrow and shows promise for improving the safety and reducing the invasiveness of pediatric bone tumor treatments.

  3. Positioning device for MRI-guided high intensity focused ultrasound system

    Energy Technology Data Exchange (ETDEWEB)

    Damianou, Christakis [Frederick Institute of Technology (FIT), Limassol (Cyprus); MEDSONIC, LTD, Limassol (Cyprus); Ioannides, Kleanthis [Polikliniki Igia, Limassol (Cyprus); Milonas, Nicos [Frederick Institute of Technology (FIT), Limassol (Cyprus)

    2008-04-15

    A prototype magnetic resonance imaging (MRI)- compatible positioning device was used to move an MRI-guided high intensity focused ultrasound (HIFU) transducer. The positioning device has three user-controlled degrees of freedom that allow access to various targeted lesions. The positioning device was designed and fabricated using construction materials selected for compatibility with high magnetic fields and fast switching magnetic field gradients encountered inside MRI scanners. The positioning device incorporates only MRI compatible materials such as piezoelectric motors, plastic sheets, brass screws, plastic pulleys and timing belts. The HIFU/MRI system includes the multiple subsystems (a) HIFU system, (b) MR imaging, (c) Positioning device (robot) and associate drivers, (d) temperature measurement, (e) cavitation detection, (f) MRI compatible camera, and (g) Soft ware. The MRI compatibility of the system was successfully demonstrated in a clinical high-field MRI scanner. The ability of the robot to accurately move the transducer thus creating discrete and overlapping lesions in biological tissue was tested successfully. A simple, cost effective, portable positioning device has been developed which can be used in virtually any clinical MRI scanner since it can be sited on the scanner's table. The propagation of HIFU can use either a lateral or superior-inferior approach. Discrete and large lesions were created successfully with reproducible results. (orig.)

  4. Enhanced high intensity focused ultrasound heat deposition for more efficient hemostasis

    Science.gov (United States)

    Labuda, Cecille Pemberton

    High intensity focused ultrasound (HIFU) is currently being developed for hemorrhage control since it provides rapid energy deposition in the form of heat in the HIFU focal region. When the HIFU focus is targeted on soft tissue wounds, the resulting elevation of tissue temperature cauterizes the tissues thus stopping the bleeding. If HIFU is targeted near blood vessels with millimeter-range diameter, the rate of heat deposition is limited by loss of heat to the blood flow. Maximizing the local heat deposition is important for the achievement of HIFU-induced hemorrhage control, or "hemostasis", near large vessels. In this study, the effect of a fiber device on the heat deposition in the HIFU focal region is investigated in tissue-mimicking flow phantoms with liquid albumen as the heat-sensitive denaturing flow fluid. The effect of the embedded fiber on albumen coagulation in the flow phantom is compared to the degree and rate of albumen coagulation when no fiber is present. The effect of the fiber device on the size of lesions formed in a heat-sensitive tissue-mimicking phantom is also investigated. Finally, finite difference time domain simulations are performed to determine the heat deposition in a tissue-mimicking phantom with a nylon disc embedded and a phantom with the nylon disc removed. The results of this study are quite promising for the possibility of increased efficacy of hemostasis for such a device in concert with HIFU in vessel-containing tissue volumes where HIFU alone is not completely effective.

  5. High Intensity Focused Ultrasound Monitoring using Harmonic Motion Imaging for Focused Ultrasound (HMIFU) under boiling or slow denaturation conditions

    Science.gov (United States)

    Hou, Gary Y.; Marquet, Fabrice; Wang, Shutao; Apostolakis, Iason-Zacharias; Konofagou, Elisa E.

    2015-01-01

    Harmonic Motion Imaging for Focused Ultrasound (HMIFU) is a recently developed High-Intensity Focused Ultrasound (HIFU) treatment monitoring method that utilizes an amplitude-modulated therapeutic ultrasound beam to induce an oscillatory radiation force at the HIFU focus and estimates the focal tissue displacement to monitor the HIFU thermal treatment. In this study, the performance of HMIFU under acoustic, thermal and mechanical effects were investigated. The performance of HMIFU was assessed in ex vivo canine liver specimens (n=13) under slow denaturation or boiling regimes. Passive Cavitation Detector (PCD) was used to assess the acoustic cavitation activity while a bare-wire thermocouple was used to monitor the focal temperature change. During lesioning with slow denaturation, high quality displacements (correlation coefficient above 0.97) were observed under minimum cavitation noise, indicating tissue the initial-softening-then-stiffening property change. During HIFU with boiling, HMIFU monitored a consistent change in lesion-to-background displacement contrast (0.46±0.37) despite the presence of strong cavitation noise due to boiling during lesion formation. Therefore, HMIFU effectively monitored softening-then-stiffening during lesioning under slow denaturation, and detected lesioning under boiling with a distinct change in displacement contrast under boiling in the presence of cavitation. In conclusion, HMIFU was shown effective in HIFU monitoring and lesioning identification without being significantly affected by cavitation noise. PMID:26168177

  6. High-intensity focused ultrasound monitoring using harmonic motion imaging for focused ultrasound (HMIFU) under boiling or slow denaturation conditions.

    Science.gov (United States)

    Hou, Gary Y; Marquet, Fabrice; Wang, Shutao; Apostolakis, Iason-Zacharias; Konofagou, Elisa E

    2015-07-01

    Harmonic motion imaging for focused ultrasound (HMIFU) is a recently developed high-intensity focused ultrasound (HIFU) treatment monitoring method that utilizes an amplitude-modulated therapeutic ultrasound beam to induce an oscillatory radiation force at the HIFU focus and estimates the focal tissue displacement to monitor the HIFU thermal treatment. In this study, the performance of HMIFU under acoustic, thermal, and mechanical effects was investigated. The performance of HMIFU was assessed in ex vivo canine liver specimens (n = 13) under slow denaturation or boiling regimes. A passive cavitation detector (PCD) was used to assess the acoustic cavitation activity, and a bare-wire thermocouple was used to monitor the focal temperature change. During lesioning with slow denaturation, high quality displacements (correlation coefficient above 0.97) were observed under minimum cavitation noise, indicating the tissue initial-softening-then- stiffening property change. During HIFU with boiling, HMIFU monitored a consistent change in lesion-to-background displacement contrast (0.46 ± 0.37) despite the presence of strong cavitation noise due to boiling during lesion formation. Therefore, HMIFU effectively monitored softening-then-stiffening during lesioning under slow denaturation, and detected lesioning under boiling with a distinct change in displacement contrast under boiling in the presence of cavitation. In conclusion, HMIFU was shown under both boiling and slow denaturation regimes to be effective in HIFU monitoring and lesioning identification without being significantly affected by cavitation noise.

  7. Effects of oxytocin on high intensity focused ultrasound (HIFU) ablation of adenomysis: A prospective study

    International Nuclear Information System (INIS)

    Zhang, Xin; Zou, Min; Zhang, Cai; He, Jia; Mao, Shihua; Wu, Qingrong; He, Min; Wang, Jian; Zhang, Ruitao; Zhang, Lian

    2014-01-01

    Objective: To investigate the effects of oxytocin on high-intensity focused ultrasound (HIFU) ablation for the treatment of adenomyosis. Materials and methods: Eighty-six patients with adenomyosis from three hospitals were randomly assigned to the oxytocin group or control group for HIFU treatment. During HIFU treatment, 80 units of oxytocin was added in 500 ml of 0.9% normal saline running at the rate of 2 ml/min (0.32 U/min) in the oxytocin group, while 0.9% normal saline was used in the control group. Both patients and HIFU operators were blinded to oxytocin or saline application. Treatment results, adverse effects were compared. Results: When using oxytocin, the non-perfused volume (NPV) ratio was 80.7 ± 11.6%, the energy-efficiency factor (EEF) was 8.1 ± 9.9 J/mm 3 , and the sonication time required to ablate 1 cm 3 was 30.0 ± 36.0 s/cm 3 . When not using oxytocin, the non-perfused volume ratio was 70.8 ± 16.7%, the EEF was 15.8 ± 19.6 J/mm 3 , and the sonication time required to ablate 1 cm 3 was 58.2 ± 72.7 S/cm 3 . Significant difference in the NPV ratio, EEF, and the sonication time required to ablate 1 cm 3 between the two groups was observed. No oxytocin related adverse effects occurred. Conclusion: Oxytocin could significantly decrease the energy for ablating adenomyosis with HIFU, safely enhance the treatment efficiency

  8. An integrated ultrasound-guided high intensity focused ultrasound system for in-vivo experiment

    Science.gov (United States)

    Liu, Dalong; Ebbini, Emad S.

    2017-03-01

    We present the system architecture of an integrated Ultrasound-guided High Intensity Focused Ultrasound (USgHIFU) system for image-guided surgery and temperature tracking in vivo. The system is capable of operating with multiple frontends. Current implementation has a SonixRP for imaging and a custom designed dual mode ultrasound array (DMUA) system (32Tx/32Rx) for imaging/therapy. The highlights of the system include a fully-programmable, multiple data stream capable data processing engine, and an arbitrarily programmable high power array driver that is able to synthesize complex beam patterns in space and time. The data processing engine features a pipeline-style design that can be programmed on-the-fly by re-arranging the pre-verified GPU-accelerated high performance pipeline blocks, which cover an extensive range from basic functions such as filtering to specialized processing like speckle tracking. Furthermore, the pipeline design also has the option of bringing in MATLAB (Mathworks, Natick, MA, US) as part of the processing chain, thus vastly increase the capability of the system. By properly balancing the processing load between GPU-enabled routine and MATLAB script. This allows one to achieve a high degree of flexibility while meeting real-time constraints. Results are presented from in vivo rat experiment. Where low dose of therapeutic ultrasound was delivered into the hind limb of the Copenhagen rats using DMUA and temperature was tracked using a linear probe (HST, Ultrasonix). The data is processed in realtime with MATLAB in the loop to perform temperature regularization. Results show that we can reliably track the low temperature heating in the presence of motion artifacts (respiration and pulsation).

  9. Modelling the temperature evolution of bone under high intensity focused ultrasound

    Science.gov (United States)

    ten Eikelder, H. M. M.; Bošnački, D.; Elevelt, A.; Donato, K.; Di Tullio, A.; Breuer, B. J. T.; van Wijk, J. H.; van Dijk, E. V. M.; Modena, D.; Yeo, S. Y.; Grüll, H.

    2016-02-01

    Magnetic resonance-guided high intensity focused ultrasound (MR-HIFU) has been clinically shown to be effective for palliative pain management in patients suffering from skeletal metastasis. The underlying mechanism is supposed to be periosteal denervation caused by ablative temperatures reached through ultrasound heating of the cortex. The challenge is exact temperature control during sonication as MR-based thermometry approaches for bone tissue are currently not available. Thus, in contrast to the MR-HIFU ablation of soft tissue, a thermometry feedback to the HIFU is lacking, and the treatment of bone metastasis is entirely based on temperature information acquired in the soft tissue adjacent to the bone surface. However, heating of the adjacent tissue depends on the exact sonication protocol and requires extensive modelling to estimate the actual temperature of the cortex. Here we develop a computational model to calculate the spatial temperature evolution in bone and the adjacent tissue during sonication. First, a ray-tracing technique is used to compute the heat production in each spatial point serving as a source term for the second part, where the actual temperature is calculated as a function of space and time by solving the Pennes bio-heat equation. Importantly, our model includes shear waves that arise at the bone interface as well as all geometrical considerations of transducer and bone geometry. The model was compared with a theoretical approach based on the far field approximation and an MR-HIFU experiment using a bone phantom. Furthermore, we investigated the contribution of shear waves to the heat production and resulting temperatures in bone. The temperature evolution predicted by our model was in accordance with the far field approximation and agreed well with the experimental data obtained in phantoms. Our model allows the simulation of the HIFU treatments of bone metastasis in patients and can be extended to a planning tool prior to MR

  10. Modelling the temperature evolution of bone under high intensity focused ultrasound

    International Nuclear Information System (INIS)

    Ten Eikelder, H M M; Bošnački, D; Breuer, B J T; Van Wijk, J H; Van Dijk, E V M; Modena, D; Yeo, S Y; Grüll, H; Elevelt, A; Donato, K; Di Tullio, A

    2016-01-01

    Magnetic resonance-guided high intensity focused ultrasound (MR-HIFU) has been clinically shown to be effective for palliative pain management in patients suffering from skeletal metastasis. The underlying mechanism is supposed to be periosteal denervation caused by ablative temperatures reached through ultrasound heating of the cortex. The challenge is exact temperature control during sonication as MR-based thermometry approaches for bone tissue are currently not available. Thus, in contrast to the MR-HIFU ablation of soft tissue, a thermometry feedback to the HIFU is lacking, and the treatment of bone metastasis is entirely based on temperature information acquired in the soft tissue adjacent to the bone surface. However, heating of the adjacent tissue depends on the exact sonication protocol and requires extensive modelling to estimate the actual temperature of the cortex. Here we develop a computational model to calculate the spatial temperature evolution in bone and the adjacent tissue during sonication. First, a ray-tracing technique is used to compute the heat production in each spatial point serving as a source term for the second part, where the actual temperature is calculated as a function of space and time by solving the Pennes bio-heat equation. Importantly, our model includes shear waves that arise at the bone interface as well as all geometrical considerations of transducer and bone geometry. The model was compared with a theoretical approach based on the far field approximation and an MR-HIFU experiment using a bone phantom. Furthermore, we investigated the contribution of shear waves to the heat production and resulting temperatures in bone. The temperature evolution predicted by our model was in accordance with the far field approximation and agreed well with the experimental data obtained in phantoms. Our model allows the simulation of the HIFU treatments of bone metastasis in patients and can be extended to a planning tool prior to MR

  11. Gold nanoparticle nucleated cavitation for enhanced high intensity focused ultrasound therapy

    Science.gov (United States)

    McLaughlan, J. R.; Cowell, D. M. J.; Freear, S.

    2018-01-01

    High intensity focused ultrasound (HIFU) or focused ultrasound surgery is a non-invasive technique for the treatment of cancerous tissue, which is limited by difficulties in getting real-time feedback on treatment progress and long treatment durations. The formation and activity of acoustic cavitation, specifically inertial cavitation, during HIFU exposures has been demonstrated to enhance heating rates. However, without the introduction of external nuclei its formation an activity can be unpredictable, and potentially counter-productive. In this study, a combination of pulse laser illumination (839 nm), HIFU exposures (3.3 MHz) and plasmonic gold nanorods (AuNR) was demonstrated as a new approach for the guidance and enhancement of HIFU treatments. For imaging, short duration HIFU pulses (10 μs) demonstrated broadband acoustic emissions from AuNR nucleated cavitation with a signal-to-noise ranging from 5-35 dB for peak negative pressures between 1.19-3.19  ±  0.01 MPa. In the absence of either AuNR or laser illumination these emissions were either not present or lower in magnitude (e.g. 5 dB for 3.19 MPa). Continuous wave (CW) HIFU exposures for 15 s, were then used to generate thermal lesions for peak negative pressures from 0.2-2.71  ±  0.01 MPa at a fluence of 3.4 mJ cm-2 . Inertial cavitation dose (ICD) was monitored during all CW exposures, where exposures combined with both laser illumination and AuNRs resulted in the highest level of detectable emissions. This parameter was integrated over the entire exposure to give a metric to compare with measured thermal lesion area, where it was found that a minimum total ICD of 1.5 × 103 a.u. was correlated with the formation of thermal lesions in gel phantoms. Furthermore, lesion area (mm2) was increased for equivalent exposures without either AuNRs or laser illumination. Once combined with cancer targeting AuNRs this approach could allow for the future theranostic use of HIFU, such as

  12. A retrospective comparison of microwave ablation and high intensity focused ultrasound for treating symptomatic uterine fibroids

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Wen-Peng, E-mail: zwp215@163.com; Han, Zhi-Yu, E-mail: hanzhiyu301@hotmail.com; Zhang, Jing, E-mail: zjbch@sina.com; Liang, Ping, E-mail: liangping301@hotmail.com

    2015-03-15

    Highlights: •Both HIFU and PMWA are thermal ablation techniques and they all provide safe and reliable alternative treatment methods for uterine fibroids. •However, whether there are obvious difference between these two kinds of approaches in improving symptom, treatment time, ablation rate, regression rate and adverse events, until now, there are no clinical trials which have been performed to compare the therapeutic effects of HIFU and PMWA. •In this research, we retrospectively compare the results of these two treatment methods. •To our knowledge, our study is the first directly comparing long-term outcome after PMWA and HIFU in patients with uterine fibroids. -- Abstract: Objectives: To retrospectively compare the effectiveness and safety of percutaneous microwave ablation (PMWA) and ultrasound-guided high-intensity focused ultrasound (USgHIFU) for treating symptomatic uterine fibroids. Methods: Seventy-three women with symptomatic uterine fibroids who met the inclusion criteria were enrolled in our study from September 2012 to December 2013. Thirty-one patients with forty uterine fibroids underwent PMWA, and forty-two patients with fifty-one uterine fibroids underwent USgHIFU. A contrast-enhanced MRI was performed before and after treatment, and all patients were followed up for 6 months. Assessment endpoints included symptom severity scores (SSS), treatment time, ablation rate, fibroid regression rate and adverse events. Results: The mean age of the patients in our study was 35.4 ± 6.2 years (range, 21–49 years), and the median volume of uterine fibroids was 95.7 cm{sup 3} (60.3–131.5 cm{sup 3}). The ablation rate of uterine fibroids was 79.8 ± 18.2% and 77.1 ± 14.9% in the PMWA group and the USgHIFU group, respectively, and showed no significant difference between the groups. Changes in SSS after PMWA were similar in the PMWA group (47.7 pre-treatment vs. 29.9 post-treatment) and USgHIFU group (42.1 pre-treatment vs. 24.6 post-treatment). The

  13. Complete high-intensity focused ultrasound in prostate cancer: outcome from the @-Registry.

    Science.gov (United States)

    Blana, A; Robertson, C N; Brown, S C W; Chaussy, C; Crouzet, S; Gelet, A; Conti, G N; Ganzer, R; Pasticier, G; Thuroff, S; Ward, J F

    2012-09-01

    To analyze data on patients with localized prostate cancer who were treated with complete high-intensity focused ultrasound (HIFU) prospectively captured within a voluntary HIFU user database (@-Registry). The @-Registry includes data from consecutive patients treated with Ablatherm (EDAP-TMS) HIFU at nine European Centres during the period 1994 and 2009. For this analysis, the data repository was reviewed for information on patients with localized prostate cancer (T1 -- T2) treated with complete (whole-gland) HIFU on the basis of an anterior-posterior prostate height of ≤24 mm and a treated volume >120% of the prostate volume. Patients were regularly followed with PSA measurement and biopsy. Biochemical failure was defined for this study as PSA nadir +2 ngml(-1) (Phoenix definition). Disease-free survival was based on a biopsy, retreatment and biochemical data. Patients were risk group-stratified using the D'Amico classification system. The median follow-up was 2.8 years for the 356 patients included in the analysis. The majority could be classified as either low (44.9%) or intermediate risk (39.6%); 14.6% patients were classified as high risk. The median (mean, s.d.) PSA nadir was 0.11 ng ml(-1) (0.78 and 3.6), achieved at a mean (s.d.) of 14.4 (11.6) weeks after HIFU. Follow-up biopsies on 226/356 (63.5%) patients revealed an overall negative biopsy rate of 80.5% (182/226); there was no statistically significant difference in positive biopsy rate by risk group-stratification. Actuarial freedom from biochemical recurrence at 5 and 7 years according to the Phoenix definition was 85% and 79%, respectively. Disease-free progression rates at 5 and 7 years were 64% and 54%, respectively. Whole-gland prostate HIFU as primary monotherapy for localized prostate cancer achieves a recurrence-free survival in short-term analysis as assessed by prostate biopsy and serum PSA endpoints in a majority of patients.

  14. Thermal and mechanical high-intensity focused ultrasound: perspectives on tumor ablation, immune effects and combination strategies

    NARCIS (Netherlands)

    Bijgaart, R.J.E. van den; Eikelenboom, D.C.; Hoogenboom, M.; Futterer, J.J.; Brok, M.H.M.G.M. den; Adema, G.J.

    2017-01-01

    Tumor ablation technologies, such as radiofrequency-, cryo- or high-intensity focused ultrasound (HIFU) ablation will destroy tumor tissue in a minimally invasive manner. Ablation generates large volumes of tumor debris in situ, releasing multiple bio-molecules like tumor antigens and

  15. A framework for continuous target tracking during MR-guided high intensity focused ultrasound thermal ablations in the abdomen

    NARCIS (Netherlands)

    Zachiu, Cornel; Denis de Senneville, Baudouin; Dmitriev, Ivan D.; Moonen, Chrit T.W.; Ries, Mario

    2017-01-01

    Background: During lengthy magnetic resonance-guided high intensity focused ultrasound (MRg-HIFU) thermal ablations in abdominal organs, the therapeutic work-flow is frequently hampered by various types of physiological motion occurring at different time-scales. If left un-addressed this can lead to

  16. Sampling strategies for subsampled segmented EPI PRF thermometry in MR guided high intensity focused ultrasound

    Science.gov (United States)

    Odéen, Henrik; Todd, Nick; Diakite, Mahamadou; Minalga, Emilee; Payne, Allison; Parker, Dennis L.

    2014-01-01

    Purpose: To investigate k-space subsampling strategies to achieve fast, large field-of-view (FOV) temperature monitoring using segmented echo planar imaging (EPI) proton resonance frequency shift thermometry for MR guided high intensity focused ultrasound (MRgHIFU) applications. Methods: Five different k-space sampling approaches were investigated, varying sample spacing (equally vs nonequally spaced within the echo train), sampling density (variable sampling density in zero, one, and two dimensions), and utilizing sequential or centric sampling. Three of the schemes utilized sequential sampling with the sampling density varied in zero, one, and two dimensions, to investigate sampling the k-space center more frequently. Two of the schemes utilized centric sampling to acquire the k-space center with a longer echo time for improved phase measurements, and vary the sampling density in zero and two dimensions, respectively. Phantom experiments and a theoretical point spread function analysis were performed to investigate their performance. Variable density sampling in zero and two dimensions was also implemented in a non-EPI GRE pulse sequence for comparison. All subsampled data were reconstructed with a previously described temporally constrained reconstruction (TCR) algorithm. Results: The accuracy of each sampling strategy in measuring the temperature rise in the HIFU focal spot was measured in terms of the root-mean-square-error (RMSE) compared to fully sampled “truth.” For the schemes utilizing sequential sampling, the accuracy was found to improve with the dimensionality of the variable density sampling, giving values of 0.65 °C, 0.49 °C, and 0.35 °C for density variation in zero, one, and two dimensions, respectively. The schemes utilizing centric sampling were found to underestimate the temperature rise, with RMSE values of 1.05 °C and 1.31 °C, for variable density sampling in zero and two dimensions, respectively. Similar subsampling schemes

  17. Sampling strategies for subsampled segmented EPI PRF thermometry in MR guided high intensity focused ultrasound

    International Nuclear Information System (INIS)

    Odéen, Henrik; Diakite, Mahamadou; Todd, Nick; Minalga, Emilee; Payne, Allison; Parker, Dennis L.

    2014-01-01

    Purpose: To investigate k-space subsampling strategies to achieve fast, large field-of-view (FOV) temperature monitoring using segmented echo planar imaging (EPI) proton resonance frequency shift thermometry for MR guided high intensity focused ultrasound (MRgHIFU) applications. Methods: Five different k-space sampling approaches were investigated, varying sample spacing (equally vs nonequally spaced within the echo train), sampling density (variable sampling density in zero, one, and two dimensions), and utilizing sequential or centric sampling. Three of the schemes utilized sequential sampling with the sampling density varied in zero, one, and two dimensions, to investigate sampling the k-space center more frequently. Two of the schemes utilized centric sampling to acquire the k-space center with a longer echo time for improved phase measurements, and vary the sampling density in zero and two dimensions, respectively. Phantom experiments and a theoretical point spread function analysis were performed to investigate their performance. Variable density sampling in zero and two dimensions was also implemented in a non-EPI GRE pulse sequence for comparison. All subsampled data were reconstructed with a previously described temporally constrained reconstruction (TCR) algorithm. Results: The accuracy of each sampling strategy in measuring the temperature rise in the HIFU focal spot was measured in terms of the root-mean-square-error (RMSE) compared to fully sampled “truth.” For the schemes utilizing sequential sampling, the accuracy was found to improve with the dimensionality of the variable density sampling, giving values of 0.65 °C, 0.49 °C, and 0.35 °C for density variation in zero, one, and two dimensions, respectively. The schemes utilizing centric sampling were found to underestimate the temperature rise, with RMSE values of 1.05 °C and 1.31 °C, for variable density sampling in zero and two dimensions, respectively. Similar subsampling schemes

  18. SU-E-J-04: Integration of Interstitial High Intensity Therapeutic Ultrasound Applicators On a Clinical MRI-Guided High Intensity Focused Ultrasound Treatment Planning Software Platform

    Energy Technology Data Exchange (ETDEWEB)

    Ellens, N [Johns Hopkins University, Baltimore, Maryland (United States); Partanen, A [Philips Healthcare, Andover, Massachusetts (United States); Ghoshal, G; Burdette, E [Acoustic MedSystems Inc., Savoy, IL (United States); Farahani, K [National Cancer Institute, Bethesda, MD (United States)

    2015-06-15

    Purpose: Interstitial high intensity therapeutic ultrasound (HITU) applicators can be used to ablate tissue percutaneously, allowing for minimally-invasive treatment without ionizing radiation [1,2]. The purpose of this study was to evaluate the feasibility and usability of combining multielement interstitial HITU applicators with a clinical magnetic resonance imaging (MRI)-guided focused ultrasound software platform. Methods: The Sonalleve software platform (Philips Healthcare, Vantaa, Finland) combines anatomical MRI for target selection and multi-planar MRI thermometry to provide real-time temperature information. The MRI-compatible interstitial US applicators (Acoustic MedSystems, Savoy, IL, USA) had 1–4 cylindrical US elements, each 1 cm long with either 180° or 360° of active surface. Each applicator (4 Fr diameter, enclosed within a 13 Fr flexible catheter) was inserted into a tissue-mimicking agar-silica phantom. Degassed water was circulated around the transducers for cooling and coupling. Based on the location of the applicator, a virtual transducer overlay was added to the software to assist targeting and to allow automatic thermometry slice placement. The phantom was sonicated at 7 MHz for 5 minutes with 6–8 W of acoustic power for each element. MR thermometry data were collected during and after sonication. Results: Preliminary testing indicated that the applicator location could be identified in the planning images and the transducer locations predicted within 1 mm accuracy using the overlay. Ablation zones (thermal dose ≥ 240 CEM43) for 2 active, adjacent US elements ranged from 18 mm × 24 mm (width × length) to 25 mm × 25 mm for the 6 W and 8 W sonications, respectively. Conclusion: The combination of interstitial HITU applicators and this software platform holds promise for novel approaches in minimally-invasive MRI-guided therapy, especially when bony structures or air-filled cavities may preclude extracorporeal HIFU.[1] Diederich et al

  19. SU-E-J-04: Integration of Interstitial High Intensity Therapeutic Ultrasound Applicators On a Clinical MRI-Guided High Intensity Focused Ultrasound Treatment Planning Software Platform

    International Nuclear Information System (INIS)

    Ellens, N; Partanen, A; Ghoshal, G; Burdette, E; Farahani, K

    2015-01-01

    Purpose: Interstitial high intensity therapeutic ultrasound (HITU) applicators can be used to ablate tissue percutaneously, allowing for minimally-invasive treatment without ionizing radiation [1,2]. The purpose of this study was to evaluate the feasibility and usability of combining multielement interstitial HITU applicators with a clinical magnetic resonance imaging (MRI)-guided focused ultrasound software platform. Methods: The Sonalleve software platform (Philips Healthcare, Vantaa, Finland) combines anatomical MRI for target selection and multi-planar MRI thermometry to provide real-time temperature information. The MRI-compatible interstitial US applicators (Acoustic MedSystems, Savoy, IL, USA) had 1–4 cylindrical US elements, each 1 cm long with either 180° or 360° of active surface. Each applicator (4 Fr diameter, enclosed within a 13 Fr flexible catheter) was inserted into a tissue-mimicking agar-silica phantom. Degassed water was circulated around the transducers for cooling and coupling. Based on the location of the applicator, a virtual transducer overlay was added to the software to assist targeting and to allow automatic thermometry slice placement. The phantom was sonicated at 7 MHz for 5 minutes with 6–8 W of acoustic power for each element. MR thermometry data were collected during and after sonication. Results: Preliminary testing indicated that the applicator location could be identified in the planning images and the transducer locations predicted within 1 mm accuracy using the overlay. Ablation zones (thermal dose ≥ 240 CEM43) for 2 active, adjacent US elements ranged from 18 mm × 24 mm (width × length) to 25 mm × 25 mm for the 6 W and 8 W sonications, respectively. Conclusion: The combination of interstitial HITU applicators and this software platform holds promise for novel approaches in minimally-invasive MRI-guided therapy, especially when bony structures or air-filled cavities may preclude extracorporeal HIFU.[1] Diederich et al

  20. Investigation of Generation, Acceleration, Transport and Final Focusing of High-Intensity Heavy Ion Beams from Sources to Targets

    Energy Technology Data Exchange (ETDEWEB)

    Chiping Chen

    2006-10-26

    Under the auspices of the research grant, the Intense Beam Theoretical Research Goup at Massachusetts Institute of Technology's Plasma Science and Fusion Center made significant contributions in a number of important areas in the HIF and HEDP research, including: (a) Derivation of rms envelope equations and study of rms envelope dynamics for high-intensity heavy ion beams in a small-aperture AG focusing transport systems; (b) Identification of a new mechanism for chaotic particle motion, halo formation, and beam loss in high-intensity heavy ion beams in a small-aperture AG focusing systems; Development of elliptic beam theory; (d) Study of Physics Issues in the Neutralization Transport Experiment (NTX).

  1. Investigation of Generation, Acceleration, Transport and Final Focusing of High-Intensity Heavy Ion Beams from Sources to Targets

    International Nuclear Information System (INIS)

    Chiping Chen

    2006-01-01

    Under the auspices of the research grant, the Intense Beam Theoretical Research Group at Massachusetts Institute of Technology's Plasma Science and Fusion Center made significant contributions in a number of important areas in the HIF and HEDP research, including: (a) Derivation of rms envelope equations and study of rms envelope dynamics for high-intensity heavy ion beams in a small-aperture AG focusing transport systems; (b) Identification of a new mechanism for chaotic particle motion, halo formation, and beam loss in high-intensity heavy ion beams in a small-aperture AG focusing systems; (c) Development of elliptic beam theory; and (d) Study of Physics Issues in the Neutralization Transport Experiment (NTX)

  2. High-Intensity Focused Ultrasound for the Treatment of Wrinkles and Skin Laxity in Seven Different Facial Areas

    OpenAIRE

    Park, Hyunchul; Kim, Eunjin; Kim, Jeongeun; Ro, Youngsuck; Ko, Jooyeon

    2015-01-01

    Background High-intensity focused ultrasound (HIFU) treatment has recently emerged in response to the increasing demand for noninvasive procedures for skin lifting and tightening. Objective This study was aimed at evaluating the clinical efficacy of and patient satisfaction with HIFU treatment for wrinkles and laxity in seven different areas of the face in Asian skin. Methods Twenty Korean patients with facial wrinkle and laxity were analyzed after a single session of HIFU treatment. Two inde...

  3. Efficient generation of cavitation bubbles and reactive oxygen species using triggered high-intensity focused ultrasound sequence for sonodynamic treatment

    Science.gov (United States)

    Yasuda, Jun; Yoshizawa, Shin; Umemura, Shin-ichiro

    2016-07-01

    Sonodynamic treatment is a method of treating cancer using reactive oxygen species (ROS) generated by cavitation bubbles in collaboration with a sonosensitizer at a target tissue. In this treatment method, both localized ROS generation and ROS generation with high efficiency are important. In this study, a triggered high-intensity focused ultrasound (HIFU) sequence, which consists of a short, extremely high intensity pulse immediately followed by a long, moderate-intensity burst, was employed for the efficient generation of ROS. In experiments, a solution sealed in a chamber was exposed to a triggered HIFU sequence. Then, the distribution of generated ROS was observed by the luminol reaction, and the amount of generated ROS was quantified using KI method. As a result, the localized ROS generation was demonstrated by light emission from the luminol reaction. Moreover, it was demonstrated that the triggered HIFU sequence has higher efficiency of ROS generation by both the KI method and the luminol reaction emission.

  4. Numerical Simulation of High Intensity Focused Ultrasound Therapy with Volume Model of Human Body

    Science.gov (United States)

    Okita, Kohei; Sugiyama, Kazuyasu; Ono, Kenji; Takagi, Shu; Matsumoto, Yoichiro

    2010-03-01

    The development of the HIFU therapy for the deeply placed cancer has been desired. On problem is the displacement of the focal point due to the inhomogeneity of human body. The objectives are to realize the appropriate phase control of an array transducer and to support the preoperative planning of HIFU therapy by the computational prediction of treatment regions. Our approach is to solve the mass and momentum equations for mixture with the equation of state of media. The heat equation with a heat source of a viscous dissipation is solved to estimate the ablation region of tissue. The ablation, i.e., the heat denaturation of protein, is modeled as a phase transition by the phase field model. The HIFU therapy with a bowl-shape array transducer for a liver cancer is simulated. As the result with a phase control, we obtain a clear focus which is closer to a target point than the focus without a phase control, when the ultrasound propagates through lib bones. In addition, the development of the ablation region is reproduced numerically.

  5. Smooth transverse and longitudinal focusing in high-intensity ion linacs

    International Nuclear Information System (INIS)

    Billen, J.H.; Takeda, Harunori; Young, L.M.

    1996-01-01

    We examine ion linac designs that start with a high energy radio- frequency quadrupole (RFQ) followed by either a drift-tube linac (DTL) or a coupled-cavity drift-tube linac (CCDTL). For high energies a conventional CCL follows the CCDTL. High RFQ output energy allows tailoring the transverse and longitudinal focusing strengths to match into the following structure. When the RFQ beam enters a higher frequency structure, the DTL or CCDTL starts with a low accelerating gradient and large negative synchronous phase. The gradient and phase both ramp up gradually to higher values. Other changes later in the machine are also gradual. Beam dynamics simulations show that these linacs require no separate matching sections. Applications include a cw 100 mA H + beam from a 350-MHz, 6.7 MeV RFQ injecting a 700 MHz CCDTL and CCL; a 7% duty 28 mA H - beam from a 402.5 MHz RFQ and DTL injecting 805 MHz structures; a cw 135 mA D + beam produced by a 175 MHz, 8 MeV RFQ and DTL; and a 2.4% duty, 80 mA H + beam using a 433 MHz 10 MeV RFQ and a 1300 MHz CCDTL. The machines take advantage of the considerable flexibility of the CCDTL. Designs can use a variety of different transverse focusing lattices. Use of two coupling cavity orientations permits a constant period even when the number of drift tubes per cavity changes along the linac

  6. Therapeutic effects of microbubble added to combined high-intensity focused ultrasound and chemotherapy in a pancreatic cancer xenograft model

    International Nuclear Information System (INIS)

    Yu, Mi Hye; Lee, Jae Young; Kim, Bo Ram; Park, Eun Joo; Kim, Hoe Suk; Han, Joon Koo; Kim, Hae Ri; Choi, Byung Ihn

    2016-01-01

    To investigate whether high-intensity focused ultrasound (HIFU) combined with microbubbles enhances the therapeutic effects of chemotherapy. A pancreatic cancer xenograft model was established using BALB/c nude mice and luciferase-expressing human pancreatic cancer cells. Mice were randomly assigned to five groups according to treatment: control (n = 10), gemcitabine alone (GEM; n = 12), HIFU with microbubbles (HIFU + MB, n = 11), combined HIFU and gemcitabine (HIGEM; n = 12), and HIGEM + MB (n = 13). After three weekly treatments, apoptosis rates were evaluated using the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay in two mice per group. Tumor volume and bioluminescence were monitored using high-resolution 3D ultrasound imaging and in vivo bioluminescence imaging for eight weeks in the remaining mice. The HIGEM + MB group showed significantly higher apoptosis rates than the other groups (p < 0.05) and exhibited the slowest tumor growth. From week 5, the tumor-volume-ratio relative to the baseline tumor volume was significantly lower in the HIGEM + MB group than in the control, GEM, and HIFU + MB groups (p < 0.05). Despite visible distinction, the HIGEM and HIGEM + MB groups showed no significant differences. High-intensity focused ultrasound combined with microbubbles enhances the therapeutic effects of gemcitabine chemotherapy in a pancreatic cancer xenograft model

  7. Therapeutic Effects of Microbubbles Added to Combined High-Intensity Focused Ultrasound and Chemotherapy in a Pancreatic Cancer Xenograft Model

    International Nuclear Information System (INIS)

    Yu, Mi Hye; Lee, Jae Young; Kim, Hae Ri; Kim, Bo Ram; Park, Eun-Joo; Kim, Hoe Suk; Han, Joon Koo; Choi, Byung Ihn

    2016-01-01

    To investigate whether high-intensity focused ultrasound (HIFU) combined with microbubbles enhances the therapeutic effects of chemotherapy. A pancreatic cancer xenograft model was established using BALB/c nude mice and luciferase-expressing human pancreatic cancer cells. Mice were randomly assigned to five groups according to treatment: control (n = 10), gemcitabine alone (GEM; n = 12), HIFU with microbubbles (HIFU + MB, n = 11), combined HIFU and gemcitabine (HIGEM; n = 12), and HIGEM + MB (n = 13). After three weekly treatments, apoptosis rates were evaluated using the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay in two mice per group. Tumor volume and bioluminescence were monitored using high-resolution 3D ultrasound imaging and in vivo bioluminescence imaging for eight weeks in the remaining mice. The HIGEM + MB group showed significantly higher apoptosis rates than the other groups (p < 0.05) and exhibited the slowest tumor growth. From week 5, the tumor-volume-ratio relative to the baseline tumor volume was significantly lower in the HIGEM + MB group than in the control, GEM, and HIFU + MB groups (p < 0.05). Despite visible distinction, the HIGEM and HIGEM + MB groups showed no significant differences. High-intensity focused ultrasound combined with microbubbles enhances the therapeutic effects of gemcitabine chemotherapy in a pancreatic cancer xenograft model

  8. Therapeutic effects of microbubble added to combined high-intensity focused ultrasound and chemotherapy in a pancreatic cancer xenograft model

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Mi Hye [Dept. of Radiology, Konkuk University Medical Center, Seoul (Korea, Republic of); Lee, Jae Young; Kim, Bo Ram; Park, Eun Joo; Kim, Hoe Suk; Han, Joon Koo [Dept. of Radiology, Seoul National University Hospital, Seoul (Korea, Republic of); Kim, Hae Ri [Dept. of Pre-Dentistry, Gangneung-Wonju National University College of Dentistry, Gangneung (Korea, Republic of); Choi, Byung Ihn [Dept. of Radiology, Chung-Ang University Hospital, Seoul (Korea, Republic of)

    2016-09-15

    To investigate whether high-intensity focused ultrasound (HIFU) combined with microbubbles enhances the therapeutic effects of chemotherapy. A pancreatic cancer xenograft model was established using BALB/c nude mice and luciferase-expressing human pancreatic cancer cells. Mice were randomly assigned to five groups according to treatment: control (n = 10), gemcitabine alone (GEM; n = 12), HIFU with microbubbles (HIFU + MB, n = 11), combined HIFU and gemcitabine (HIGEM; n = 12), and HIGEM + MB (n = 13). After three weekly treatments, apoptosis rates were evaluated using the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay in two mice per group. Tumor volume and bioluminescence were monitored using high-resolution 3D ultrasound imaging and in vivo bioluminescence imaging for eight weeks in the remaining mice. The HIGEM + MB group showed significantly higher apoptosis rates than the other groups (p < 0.05) and exhibited the slowest tumor growth. From week 5, the tumor-volume-ratio relative to the baseline tumor volume was significantly lower in the HIGEM + MB group than in the control, GEM, and HIFU + MB groups (p < 0.05). Despite visible distinction, the HIGEM and HIGEM + MB groups showed no significant differences. High-intensity focused ultrasound combined with microbubbles enhances the therapeutic effects of gemcitabine chemotherapy in a pancreatic cancer xenograft model.

  9. Therapeutic Effects of Microbubbles Added to Combined High-Intensity Focused Ultrasound and Chemotherapy in a Pancreatic Cancer Xenograft Model

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Mi Hye [Department of Radiology, Konkuk University Medical Center, Seoul 05030 (Korea, Republic of); Lee, Jae Young [Department of Radiology, Seoul National University Hospital, Seoul 03080 (Korea, Republic of); Kim, Hae Ri [Department of Pre-Dentistry, Gangneung-Wonju National University College of Dentistry, Gangneung 25457 (Korea, Republic of); Kim, Bo Ram; Park, Eun-Joo; Kim, Hoe Suk; Han, Joon Koo [Department of Radiology, Seoul National University Hospital, Seoul 03080 (Korea, Republic of); Choi, Byung Ihn [Department of Radiology, Chung-Ang University Hospital, Seoul 06973 (Korea, Republic of)

    2016-11-01

    To investigate whether high-intensity focused ultrasound (HIFU) combined with microbubbles enhances the therapeutic effects of chemotherapy. A pancreatic cancer xenograft model was established using BALB/c nude mice and luciferase-expressing human pancreatic cancer cells. Mice were randomly assigned to five groups according to treatment: control (n = 10), gemcitabine alone (GEM; n = 12), HIFU with microbubbles (HIFU + MB, n = 11), combined HIFU and gemcitabine (HIGEM; n = 12), and HIGEM + MB (n = 13). After three weekly treatments, apoptosis rates were evaluated using the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay in two mice per group. Tumor volume and bioluminescence were monitored using high-resolution 3D ultrasound imaging and in vivo bioluminescence imaging for eight weeks in the remaining mice. The HIGEM + MB group showed significantly higher apoptosis rates than the other groups (p < 0.05) and exhibited the slowest tumor growth. From week 5, the tumor-volume-ratio relative to the baseline tumor volume was significantly lower in the HIGEM + MB group than in the control, GEM, and HIFU + MB groups (p < 0.05). Despite visible distinction, the HIGEM and HIGEM + MB groups showed no significant differences. High-intensity focused ultrasound combined with microbubbles enhances the therapeutic effects of gemcitabine chemotherapy in a pancreatic cancer xenograft model.

  10. Volumetric intensity dependence on the formation of molecular and atomic ions within a high intensity laser focus.

    Science.gov (United States)

    Robson, Lynne; Ledingham, Kenneth W D; McKenna, Paul; McCanny, Thomas; Shimizu, Seiji; Yang, Jiamin M; Wahlström, Claes-Göran; Lopez-Martens, Rodrigo; Varju, Katalin; Johnsson, Per; Mauritsson, Johan

    2005-01-01

    The mechanism of atomic and molecular ionization in intense, ultra-short laser fields is a subject which continues to receive considerable attention. An inherent difficulty with techniques involving the tight focus of a laser beam is the continuous distribution of intensities contained within the focus, which can vary over several orders of magnitude. The present study adopts time of flight mass spectrometry coupled with a high intensity (8 x 10(15) Wcm(-2)), ultra-short (20 fs) pulse laser in order to investigate the ionization and dissociation of the aromatic molecule benzene-d1 (C(6)H(5)D) as a function of intensity within a focused laser beam, by scanning the laser focus in the direction of propagation, while detecting ions produced only in a "thin" slice (400 and 800 microm) of the focus. The resultant TOF mass spectra varies significantly, highlighting the dependence on the range of specific intensities accessed and their volumetric weightings on the ionization/dissociation pathways accessed.

  11. Development of a Tissue-Mimicking Phantom for Evaluating the Focusing Performance of High Intensity Focused Ultrasound

    International Nuclear Information System (INIS)

    Jing Zongyu; Li Faqi; Zou Jiangzhong; Wang Zhibiao

    2006-01-01

    Objectives: To develop a tissue mimicking phantom which can be used to evaluate the focusing performance of the HIFU transducer, and the phantom should has the same acoustic characteristic and thermotics characteristic as the biological tissue. Materials and methods: The tissue mimicking phantom was made from water, gelatin, fresh biologic tissue Its ultrasonic parameters (attenuation coefficient) of the phantom was measured by the method of radiation pressure, and thermotics parameters of the phantom, including thermal conductivity, specific heat/fusion point et al were tested under the Measurement meter. The HIFU biological effect of the phantom was evaluated under the Model JC focused ultrasound tumor therapeutic system, developed and produced by Chongqing HIFU Technology Co. Ltd (working frequency: 0.7MHz; acoustic power: 200W; focal distance: 135mm; Acoustic focal region: 3x3x25 cubic mm). Results: The self-made phantom is sable, has smooth and glossy appearance, well-distributed construction, and good elasticity. We measured the followed values for acoustic and thermal properties: density 1049±2 kg/m3; attenuation 0.532±0.017 dB/cm (0.8 MHz), 0.612±0.021 dB/cm (1.0 MHz); thermal conductivity 0.76±0.08 W/m/- deg. C; specific heat 3653±143 J/kg- deg. C; fusion point154±8 deg. C. The BFR induced in the phantom after HIFU exposure was stable in its size and appearance. Conclusion: We produced and improved one tissue mimicking phantom successfully which had semblable ultrasound and thermphysical properties like the soft tissue, and can replace the bovine liver to investigate the HIFU biological effect and to detect the focusing performance of the HIFU energy transducer. The research was supported by Chongqing University of Medical Science (CX200320)

  12. High-Intensity Focused Ultrasound (HIFU) Using Sonablate-500 for the Treatment of Localized Prostate Cancer: 6-year experience

    Science.gov (United States)

    Uchida, Toyoaki; Shoji, Sunao; Nagata, Yoshihiro

    2006-05-01

    We evaluated 281 patients of localized prostate cancer treated with high-intensity focused ultrasound (HIFU) for biochemical disease-free rate, safety, morbidity and predictors of biochemical outcome. A total of 281 patients underwent HIFU with the use of Sonablate-500 and with at least 12 months of follow-up. Biochemical failure was defined according to the criteria recommended by the American Society for Therapeutic Radiology and Oncology Consensus Panel. The biochemical disease-free rates at 1, 3 and 5 years in all patients were 78%, 74% and 72%, respectively. The biochemical disease-free rates at 5 years for patients with pretreatment PSA less than 10 ng/ml, 10.01 to 20.0 ng/ml and more than 20.0 ng/ml were 88%, 70% and 17%, respectively (ppatients with localized prostate cancer, especially those with a pretreatment PSA level less than 20 ng/ml.

  13. Decline of the self-focusing of a pulsed high intensity electron beam owing to gas breakdown

    International Nuclear Information System (INIS)

    Hotta, H.; Arai, H.

    1977-01-01

    The self-focusing of a pulsed high-intensity electron beam in a gas declines in the intermediate pressure region owing to gas breakdown. The degree of the self-focusing of a beam from a Febetron 706 in monatomic gases increases by increasing the breakdown time (t/sub B/), which is defined as the time when the plasma conductivity becomes 10 mho/cm. Secondary electrons are consumed appreciably in polyatomic gases after t/sub B/ through their reactions with ions and neutral molecules. Therefore, in such gases, the amount of the consumption must be estimated to analyze the self-focusing. For the estimation of the consumption, we must remark that the mean energy of secondary electrons is quite different between before and after t/sub B/ because of the different strength of induced longitudinal electric field. As a result of the numerical analyses, we obtain the equation t/sub B/-t/sub N/ =12/w (α-eta) (t/sub N/ is neutralization time, w is electron drift velocity, α is the first Townsend ionization coefficient, and eta is the electron attachment coefficient). Since eta is usually negligibly small before t/sub B/ and t/sub N/ is also negligibly small above a certain pressure, t/sub B/ is approximately inversely proportional to wα. The t/sub B/ in polyatomic gases, however, must be corrected for the consumption described above

  14. MR-Guided High-Intensity Focused Ultrasound Ablation of Breast Cancer with a Dedicated Breast Platform

    Energy Technology Data Exchange (ETDEWEB)

    Merckel, Laura G., E-mail: L.G.Merckel-2@umcutrecht.nl [University Medical Center Utrecht, Department of Radiology (Netherlands); Bartels, Lambertus W., E-mail: W.Bartels@umcutrecht.nl [University Medical Center Utrecht, Image Sciences Institute (Netherlands); Koehler, Max O., E-mail: max.kohler@philips.com [Philips Healthcare (Finland); Bongard, H. J. G. Desiree van den, E-mail: D.vandenBongard@umcutrecht.nl [University Medical Center Utrecht, Department of Radiotherapy (Netherlands); Deckers, Roel, E-mail: R.Deckers-2@umcutrecht.nl [University Medical Center Utrecht, Image Sciences Institute (Netherlands); Mali, Willem P. Th. M., E-mail: W.Mali@umcutrecht.nl [University Medical Center Utrecht, Department of Radiology (Netherlands); Binkert, Christoph A., E-mail: Christoph.Binkert@ksw.ch [Cantonal Hospital Winterthur, Department of Radiology (Switzerland); Moonen, Chrit T., E-mail: C.Moonen@umcutrecht.nl [University Medical Center Utrecht, Image Sciences Institute (Netherlands); Gilhuijs, Kenneth G. A., E-mail: K.G.A.Gilhuijs@umcutrecht.nl; Bosch, Maurice A. A. J. van den, E-mail: mbosch@umcutrecht.nl [University Medical Center Utrecht, Department of Radiology (Netherlands)

    2013-04-15

    Optimizing the treatment of breast cancer remains a major topic of interest. In current clinical practice, breast-conserving therapy is the standard of care for patients with localized breast cancer. Technological developments have fueled interest in less invasive breast cancer treatment. Magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) is a completely noninvasive ablation technique. Focused beams of ultrasound are used for ablation of the target lesion without disrupting the skin and subcutaneous tissues in the beam path. MRI is an excellent imaging method for tumor targeting, treatment monitoring, and evaluation of treatment results. The combination of HIFU and MR imaging offers an opportunity for image-guided ablation of breast cancer. Previous studies of MR-HIFU in breast cancer patients reported a limited efficacy, which hampered the clinical translation of this technique. These prior studies were performed without an MR-HIFU system specifically developed for breast cancer treatment. In this article, a novel and dedicated MR-HIFU breast platform is presented. This system has been designed for safe and effective MR-HIFU ablation of breast cancer. Furthermore, both clinical and technical challenges are discussed, which have to be solved before MR-HIFU ablation of breast cancer can be implemented in routine clinical practice.

  15. Noninvasive, in vivo determination of uterine fibroid thermal conductivity in MRI-guided high intensity focused ultrasound therapy.

    Science.gov (United States)

    Zhang, Jiming; Fischer, John; Warner, Lizette; Oto, Aytekin; Hor, Pei-Herng; Muthupillai, Raja

    2015-06-01

    To estimate the local thermal conductivity of uterine fibroid in vivo at a high temperature range (60-80°C) typically encountered in magnetic resonance imaging-guided high-intensity focused ultrasound (MRgHIFU) surgery. The thermal conductivity of uterine fibroids in vivo is unknown and knowledge about tissue thermal conductivity may aid in effective delivery of thermal energy for ablation. All subjects (nine women) provided written informed consent to participate in this Institutional Review Board-approved study. A total of 10 fibroids were treated using MRgHIFU surgery with real-time temperature monitoring during both heating and cooling periods. The local thermal conductivity was determined by analyzing the spatiotemporal spread of temperature during the cooling period. The thermal conductivity of MRgHIFU-treated uterine fibroids was 0.47 ± 0.07 W·m(-1) ·K(-1) (range: 0.25∼0.67 W·m(-1) ·K(-1) ) which is slightly lower than the reported value for skeletal muscle at temperatures of thermal conductivity of uterine fibroids in vivo from the spatiotemporal spread of temperature around the HIFU focus during the cooling period. © 2014 Wiley Periodicals, Inc.

  16. The role of acoustic nonlinearity in tissue heating behind the rib cage using high intensity focused ultrasound phased array

    Science.gov (United States)

    Yuldashev, Petr V.; Shmeleva, Svetlana M.; Ilyin, Sergey A.; Sapozhnikov, Oleg A.; Gavrilov, Leonid R.; Khokhlova, Vera A.

    2013-01-01

    The goal of this study was to investigate theoretically the effects of nonlinear propagation in a high intensity focused ultrasound (HIFU) field produced by a therapeutic phased array and the resultant heating of tissue behind a rib cage. Three configurations of focusing were simulated: in water, in water with ribs in the beam path, and in water with ribs backed by a layer of soft tissue. The Westervelt equation was used to model the nonlinear HIFU field and a 1 MHz phased array consisting of 254 circular elements was used as a boundary condition to the model. The temperature rise in tissue was modelled using the bioheat equation, and thermally necrosed volumes were calculated using the thermal dose formulation. The shapes of lesions predicted by the modelling were compared with those previously obtained in in vitro experiments at low power sonications. Intensity levels at the face of the array elements that corresponded to formation of high amplitude shock fronts in the focal region were determined as 10 W·cm−2 in the free field in water and 40 W·cm−2 in the presence of ribs. It was shown that exposures with shocks provided a substantial increase in tissue heating, and its better spatial localization in the main focal region only. The relative effects of overheating ribs and splitting of the focus due to the periodic structure of the ribs were therefore reduced. These results suggest that utilizing nonlinear propagation and shock formation effects can be beneficial for inducing confined HIFU lesions when irradiating through obstructions such as ribs. Design of compact therapeutic arrays to provide maximum power outputs with lower intensity levels at the elements is necessary to achieve shock wave regimes for clinically relevant sonication depths in tissue. PMID:23528338

  17. High-Intensity Focused Ultrasound for the Treatment of Wrinkles and Skin Laxity in Seven Different Facial Areas.

    Science.gov (United States)

    Park, Hyunchul; Kim, Eunjin; Kim, Jeongeun; Ro, Youngsuck; Ko, Jooyeon

    2015-12-01

    High-intensity focused ultrasound (HIFU) treatment has recently emerged in response to the increasing demand for noninvasive procedures for skin lifting and tightening. This study was aimed at evaluating the clinical efficacy of and patient satisfaction with HIFU treatment for wrinkles and laxity in seven different areas of the face in Asian skin. Twenty Korean patients with facial wrinkle and laxity were analyzed after a single session of HIFU treatment. Two independent, blinded clinicians evaluated the clinical improvement in seven areas of the face by comparison of standardized photographs obtained before, and at 3 and 6 months after treatment. Assessment of subjective satisfaction and adverse effects of treatment were done by using questionnaires. The physicians' evaluation and patients' satisfaction with the clinical effects of HIFU in each area were similar regardless of the number of treatment shots. The jawline, cheek, and perioral areas were the sites where HIFU was most effective, in decreasing order. The adverse effects included erythema and swelling in six cases, and purpura and bruising in two cases. However, the adverse effects were mild and transient. HIFU could be a safe, effective, and noninvasive procedure that can be used to improve facial wrinkles and skin laxity in Asian skin. It is particularly effective for clinical improvement in the jawline, cheek, and perioral areas.

  18. Imaging high-intensity focused ultrasound-induced tissue denaturation by multispectral photoacoustic method: an ex vivo study.

    Science.gov (United States)

    Sun, Yao; O'Neill, Brian

    2013-03-10

    We present an ex vivo study for the first time, to the best of our knowledge, in multispectral photoacoustic imaging (PAI) of tissue denaturation induced by high-intensity focused ultrasound (HIFU) in this paper. Tissue of bovine muscle was thermally treated in a heated water bath and by HIFU, and then was imaged using a multispectral photoacoustic approach. Light at multiple optical wavelengths between 700 and 900 nm was delivered to the treated bovine muscle tissue to excite the photoacoustic signal. Apparent tissue denaturation has been observed in multispectral photoacoustic images after being treated in a water bath and by HIFU. It is interesting that the denaturation is more striking at shorter optical wavelength photoacoustic images than at longer optical wavelength photoacoustic images. Multispectral photoacoustic images of the tissue denaturation were further analyzed and the photoacoustic spectrums of the denaturized tissue were calculated in this paper. This study suggests that a multispectral PAI approach might be a promising tool to evaluate tissue denaturation induced by HIFU treatment.

  19. First clinical experience with a dedicated MRI-guided high-intensity focused ultrasound system for breast cancer ablation

    Energy Technology Data Exchange (ETDEWEB)

    Merckel, Laura G.; Knuttel, Floor M.; Peters, Nicky H.G.M.; Mali, Willem P.T.M.; Bosch, Maurice A.A.J. van den [University Medical Center Utrecht, Department of Radiology, HP E 01.132, Utrecht (Netherlands); Deckers, Roel; Moonen, Chrit T.W.; Bartels, Lambertus W. [University Medical Center Utrecht, Image Sciences Institute, Utrecht (Netherlands); Dalen, Thijs van [Diakonessenhuis Utrecht, Department of Surgery, Utrecht (Netherlands); Schubert, Gerald [Philips Healthcare, Best (Netherlands); Weits, Teun [Diakonessenhuis Utrecht, Department of Radiology, Utrecht (Netherlands); Diest, Paul J. van [University Medical Center Utrecht, Department of Pathology, Utrecht (Netherlands); Vaessen, Paul H.H.B. [University Medical Center Utrecht, Department of Anesthesiology, Utrecht (Netherlands); Gorp, Joost M.H.H. van [Diakonessenhuis Utrecht, Department of Pathology, Utrecht (Netherlands)

    2016-11-15

    To assess the safety and feasibility of MRI-guided high-intensity focused ultrasound (MR-HIFU) ablation in breast cancer patients using a dedicated breast platform. Patients with early-stage invasive breast cancer underwent partial tumour ablation prior to surgical resection. MR-HIFU ablation was performed using proton resonance frequency shift MR thermometry and an MR-HIFU system specifically designed for breast tumour ablation. The presence and extent of tumour necrosis was assessed by histopathological analysis of the surgical specimen. Pearson correlation coefficients were calculated to assess the relationship between sonication parameters, temperature increase and size of tumour necrosis at histopathology. Ten female patients underwent MR-HIFU treatment. No skin redness or burns were observed in any of the patients. No correlation was found between the applied energy and the temperature increase. In six patients, tumour necrosis was observed with a maximum diameter of 3-11 mm. In these patients, the number of targeted locations was equal to the number of areas with tumour necrosis. A good correlation was found between the applied energy and the size of tumour necrosis at histopathology (Pearson = 0.76, p = 0.002). Our results show that MR-HIFU ablation with the dedicated breast system is safe and results in histopathologically proven tumour necrosis. (orig.)

  20. Single High Intensity Focused Ultrasound Session as a Whole Gland Primary Treatment for Clinically Localized Prostate Cancer: 10-Year Outcomes

    Directory of Open Access Journals (Sweden)

    Ksenija Limani

    2014-01-01

    Full Text Available Objectives. To assess the treatment outcomes of a single session of whole gland high intensity focused ultrasound (HIFU for patients with localized prostate cancer (PCa. Methods. Response rates were defined using the Stuttgart and Phoenix criteria. Complications were graded according to the Clavien score. Results. At a median follow-up of 94months, 48 (44.4% and 50 (46.3% patients experienced biochemical recurrence for Phoenix and Stuttgart definition, respectively. The 5- and 10-year actuarial biochemical recurrence free survival rates were 57% and 40%, respectively. The 10-year overall survival rate, cancer specific survival rate, and metastasis free survival rate were 72%, 90%, and 70%, respectively. Preoperative high risk category, Gleason score, preoperative PSA, and postoperative nadir PSA were independent predictors of oncological failure. 24.5% of patients had self-resolving LUTS, 18.2% had urinary tract infection, and 18.2% had acute urinary retention. A grade 3b complication occurred in 27 patients. Pad-free continence rate was 87.9% and the erectile dysfunction rate was 30.8%. Conclusion. Single session HIFU can be alternative therapy for patients with low risk PCa. Patients with intermediate risk should be informed about the need of multiple sessions of HIFU and/or adjuvant treatments and HIFU performed very poorly in high risk patients.

  1. Transarterial infusion chemotherapy combined with high intensity focused ultrasound for the treatment of pancreatic carcinomas: a clinical study

    International Nuclear Information System (INIS)

    Zhang Yiping; Zhao Jingzhi; Qiao Xinrong; Huang Hankui

    2011-01-01

    Objective: To assess the clinical value of transarterial infusion chemotherapy combined with high intensity focused ultrasound (HIFU) for the treatment of pancreatic carcinomas. Methods: A total of 64 patients with inoperable pancreatic carcinomas were randomly divided into study group (n=32) and control group (n=32). Transarterial infusion chemotherapy combined with HIFU was employed in patients of study group, while simple transarterial infusion chemotherapy was conducted in patients of control group. The effective rate, the clinical benefit rate (CBR), the occurrence of side effect and the survival time of the two groups were recorded. The results were compared between the two groups. Results: The effective rate (PR + MR), the median survival time and the one-year survival rate of the study group were 55.56%, 13.0 months and 68.75% respectively, while the effective rate (PR + MR), the median survival time and the one-year survival rate of the control group were 28.57%, 9.0 months and 43.75% respectively. Both the effective rate and the one-year survival rate of the study group were significantly higher than those of the control group (P<0.05). Conclusion: Compared with pure transarterial infusion chemotherapy, transarterial infusion chemotherapy combined with HIFU can significantly improve the short-term efficacy and increase the one-year survival rate for patients with advanced pancreatic carcinomas. (authors)

  2. Polylactic acid nano- and microchamber arrays for encapsulation of small hydrophilic molecules featuring drug release via high intensity focused ultrasound.

    Science.gov (United States)

    Gai, Meiyu; Frueh, Johannes; Tao, Tianyi; Petrov, Arseniy V; Petrov, Vladimir V; Shesterikov, Evgeniy V; Tverdokhlebov, Sergei I; Sukhorukov, Gleb B

    2017-06-01

    Long term encapsulation combined with spatiotemporal release for a precisely defined quantity of small hydrophilic molecules on demand remains a challenge in various fields ranging from medical drug delivery, controlled release of catalysts to industrial anti-corrosion systems. Free-standing individually sealed polylactic acid (PLA) nano- and microchamber arrays were produced by one-step dip-coating a PDMS stamp into PLA solution for 5 s followed by drying under ambient conditions. The wall thickness of these hydrophobic nano-microchambers is tunable from 150 nm to 7 μm by varying the PLA solution concentration. Furthermore, small hydrophilic molecules were successfully in situ precipitated within individual microchambers in the course of solvent evaporation after sonicating the PLA@PDMS stamp to remove air-bubbles and to load the active substance containing solvent. The cargo capacity of single chambers was determined to be in the range of several picograms, while it amounts to several micrograms per cm 2 . Two different methods for sealing chambers were compared: microcontact printing versus dip-coating whereby microcontact printing onto a flat PLA sheet allows for entrapment of micro-air-bubbles enabling microchambers with both ultrasound responsiveness and reduced permeability. Cargo release triggered by external high intensity focused ultrasound (HIFU) stimuli is demonstrated by experiment and compared with numerical simulations.

  3. Use of high-intensity focused ultrasound in the treatment of both benign and malignant prostatic disease

    Science.gov (United States)

    Kernen, Kenneth M.; Miles, Brian J.

    2000-05-01

    Prostate cancer, the most common malignancy in men in the United States, accounts for more than 29% of all male cancers diagnosed and 13% of all cancer deaths. This translates into approximately 200,000 men diagnosed and 37,000 men who will die from the disease this year in this country. A significant number of patients ultimately choose external beam radiation or interstitial radioactive implants (brachytherapy) combined with external beam radiotherapy as their primary treatment. Approximately 25 - 35% of external beam irradiation patients and 20 - 30% of interstitial implants combined with external beam radiotherapy will fail within 10 years. The treatment options for patients with localized radiorecurrent disease include watchful waiting, endocrine therapy, salvage radiotherapy, and salvage radical prostatectomy, cryotherapy and now high intensity focused ultrasound therapy (HIFU). Although some studies regarding watchful waiting demonstrated comparable results to formal treatment for early prostate cancer, other studies have shown metastatic and mortality rates that are significantly higher, and that radiorecurrent patients would have even greater rates of metastasis and progression to death. Prostate cancer cure by means of endocrine therapy is highly unlikely and its role is still one of palliation with a side effect profile which includes hot flashes, osteoporosis, fatigue, loss of muscle mass, anemia, loss of libido and potency. The role of salvage radiotherapy may offer local control, however long term efficacy has yet to be determined. In a recent series, only 50% of the patients were controlled for a mean of four years with salvage radiotherapy. Salvage prostatectomy has the advantage of providing excellent local control and even a cure if the cancer is confined to the prostate or within the surrounding periprostatic tissue. Historically, salvage prostatectomy is technically demanding and fraught with higher complications. In one large series

  4. Monitoring imaging of lesions induced by high intensity focused ultrasound based on differential ultrasonic attenuation and integrated backscatter estimation.

    Science.gov (United States)

    Zhong, Hui; Wan, Ming-Xi; Jiang, Yi-Feng; Wang, Su-Pin

    2007-01-01

    We investigated the feasibility of two monitoring imaging methods to visualize and evaluate the high intensity focused ultrasound (HIFU) induced lesions in vitro during and after their formation, which were based on differential ultrasonic parameter estimation. Firstly, ultrasonic attenuation slope of tissue sample was estimated based on the spectral analysis of ultrasound RF backscattered signals. The differential attenuation slope maps were acquired, which were interpreted as the differences between the pretreatment image and those obtained in different stages during HIFU therapy. Secondly, ultrasonic integrated backscatter (IBS), defined as the frequency average of the backscatter transfer function over the useful bandwidth, was proposed quantitatively to evaluate the extent of lesions with the same RF signals as the first method. Differential IBS maps were also acquired to visualize temporal evolution of lesion formation. It was found in pig liver in vitro that more precise definition of the treated area was obtained from the differential IBS images than from differential attenuation slope images. Dramatic increase in both attenuation and IBS value was observed during the therapy, which may be related to dramatic enhancement of cavitation due to boiling and accompanying tissue damage. Two methods to obtain one differential image were compared and the cumulative differential image was found to be able to eliminate noises and artifacts to some extent, which was the cumulation of a series of differential images acquired from the differences between the temporally adjacent RF data frames. Moreover, we presented a bidirectional color code for identification of the artifacts due to tissue movements caused by HIFU radiation force. We conclude that cumulative differential IBS images have the potential to monitor the formation of HIFU-induced lesions.

  5. Concurrent Chemotherapy and Pulsed High-Intensity Focused Ultrasound Therapy for the Treatment of Unresectable Pancreatic Cancer: Initial Experiences

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Young; Choi, Byung Ihn; Ryu, Ji Kon; Kim, Yong Tae; Kim, Se Hyung; Han, Joon Koo [Seoul National University Hospital, Seoul (Korea, Republic of); Hwang, Joo Ha [University of Washington Medical Center, Seattle (United States)

    2011-04-15

    This study was performed to evaluate the potential clinical value of concurrent chemotherapy and pulsed high intensity focused ultrasound (HIFU) therapy (CCHT), as well as the safety of pulsed HIFU, for the treatment of unresectable pancreatic cancer. Twelve patients were treated with HIFU from October 2008 to May 2010, and three of them underwent CCHT as the main treatment (the CCHT group). The overall survival (OS), the time to tumor progression (TTP), the complications and the current performance status in the CCHT and non-CCHT groups were analyzed. Nine patients in the non-CCHT group were evaluated to determine why CCHT could not be performed more than twice. The OS of the three patients in the CCHT group was 26.0, 21.6 and 10.8 months, respectively, from the time of diagnosis. Two of them were alive at the time of preparing this manuscript with an excellent performance status, and one of them underwent a surgical resection one year after the initiation of CCHT. The TTP of the three patients in the CCHT group was 13.4, 11.5 and 9.9 months, respectively. The median OS and TTP of the non-CCHT group were 10.3 months and 4.4 months, respectively. The main reasons why the nine patients of the non-CCHT group failed to undergo CCHT more than twice were as follows: pancreatitis (n = 1), intolerance of the pain during treatment (n = 4), palliative use of HIFU for pain relief (n = 1) and a poor physical condition due to disease progression (n = 3). No major complications were encountered except one case of pancreatitis. This study shows that CCHT is a potentially effective and safe modality for the treatment of unresectable pancreatic cancer

  6. Non-invasive Measurement of Thermal Diffusivity Using High-Intensity Focused Ultrasound and Through-Transmission Ultrasonic Imaging.

    Science.gov (United States)

    Yeshurun, Lilach; Azhari, Haim

    2016-01-01

    Thermal diffusivity at the site ablated by high-intensity focused ultrasound (HIFU) plays an important role in the final therapeutic outcome, as it influences the temperature's spatial and temporal distribution. Moreover, as tissue thermal diffusivity is different in tumors as compared with normal tissue, it could also potentially be used as a new source of imaging contrast. The aim of this study was to examine the feasibility of combining through-transmission ultrasonic imaging and HIFU to estimate thermal diffusivity non-invasively. The concept was initially evaluated using a computer simulation. Then it was experimentally tested on phantoms made of agar and ex vivo porcine fat. A computerized imaging system combined with a HIFU system was used to heat the phantoms to temperatures below 42°C to avoid irreversible damage. Through-transmission scanning provided the time-of-flight values in a region of interest during its cooling process. The time-of-flight values were consequently converted into mean values of speed of sound. Using the speed-of-sound profiles along with the developed model, we estimated the changes in temperature profiles over time. These changes in temperature profiles were then used to calculate the corresponding thermal diffusivity of the studied specimen. Thermal diffusivity for porcine fat was found to be lower by one order of magnitude than that obtained for agar (0.313×10(-7)m(2)/s vs. 4.83×10(-7)m(2)/s, respectively, p ultrasound thermal diffusivity mapping is feasible. The suggested method may particularly be suitable for breast scanning. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  7. Histopathology of breast cancer after magnetic resonance-guided high-intensity focused ultrasound and radiofrequency ablation.

    Science.gov (United States)

    Knuttel, Floortje M; Waaijer, Laurien; Merckel, Laura G; van den Bosch, Maurice A A J; Witkamp, Arjen J; Deckers, Roel; van Diest, Paul J

    2016-08-01

    Magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) ablation and radiofrequency ablation (RFA) are being researched as possible substitutes for surgery in breast cancer patients. The histopathological appearance of ablated tissue has not been studied in great detail. This study aimed to compare histopathological features of breast cancer after MR-HIFU ablation and RFA. MR-HIFU ablation and RFA were performed in- and ex-vivo. Tumours in six mastectomy specimens were partially ablated with RFA or MR-HIFU. In-vivo MR-HIFU ablation was performed 3-6 days before excision; RFA was performed in the operation room. Tissue was fixed in formalin and processed to haematoxylin and eosin (H&E) and cytokeratin-8 (CK-8)-stained slides. Morphology and cell viability were assessed. Ex-vivo ablation resulted in clear morphological changes after RFA versus subtle differences after MR-HIFU. CK-8 staining was decreased or absent. H&E tended to underestimate the size of thermal damage. In-vivo MR-HIFU resulted in necrotic-like changes. Surprisingly, some ablated lesions were CK-8-positive. Histopathology after in-vivo RFA resembled ex-vivo RFA, with hyper-eosinophilic stroma and elongated nuclei. Lesion borders were sharp after MR-HIFU and indistinct after RFA. Histopathological differences between MR-HIFU-ablated tissue and RF-ablated tissue were demonstrated. CK-8 was more reliable for cell viability assessment than H&E when used directly after ablation, while H&E was more reliable in ablated tissue left in situ for a few days. Our results contribute to improved understanding of histopathological features in breast cancer lesions treated with minimally invasive ablative techniques. © 2016 John Wiley & Sons Ltd.

  8. Therapeutic response assessment of high intensity focused ultrasound therapy for uterine fibroid: Utility of contrast-enhanced ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Xiaodong [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China)]. E-mail: zhouxd@fmmu.edu.cn; Ren Xiaolong [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China)]. E-mail: renxiaolong70@hotmail.com; Zhang Jun [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); He Guangbin [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Zheng Minjuan [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Tian Xue [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Li Li [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Zhu Ting [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Zhang Min [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Wang Lei [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Luo Wen [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China)

    2007-05-15

    Purpose: To assess the utility of contrast-enhanced ultrasonography (ceUS) in the assessment of the therapeutic response to high intensity focused ultrasound (HIFU) ablation in patients with uterine fibroid. Materials and methods: Sixty-four patients with a total of 64 uterine fibroids (mean: 5.3 {+-} 1.2 cm; range: 3.2-8.9 cm) treated with HIFU ablation under the ultrasound guidance were evaluated with ceUS after receiving an intravenous bolus injection of a microbubble contrast agent (SonoVue) within 1 week after intervention. We obtained serial ceUS images during the time period from beginning to 5 min after the initiation of the bolus contrast injection. All of the patients underwent a contrast enhanced MRI (ceMRI) and ultrasound guided needle puncture biopsy within 1 week after HIFU ablation. And as a follow-up, all of the patients underwent US at 1, 3, 6 and 12 months after HIFU treatment. The volume change was observed and compared to pre- and post-HIFU ablation. The results of the ceUS were compared with those of the ceMRI in terms of the presence or absence of residual unablated tumor and pathologic change in the treated lesions. Results: On ceUS, diagnostic accuracy was 100%, while residual unablated tumors were found in three uterine fibroids (4.7%) and failed treatment was found in eight uterine fibroids (12.5%). All the 11 fibroids were subjected to additional HIFU ablation. Of the 58 ablated fibroids without residual tumors on both the ceUS and ceMRI after the HIFU ablation, the volumes of all the fibroids decreased in different degrees during the 1 year follow-up USs. And histologic examinations confirmed findings of necrotic and viable tumor tissue, respectively. Conclusion: CEUS is potentially useful for evaluating the early therapeutic effect of percutaneous HIFU ablation for uterine fibroids.

  9. Contrast-Enhanced Ultrasound for Evaluation of High-Intensity Focused Ultrasound Treatment of Benign Uterine Diseases

    Science.gov (United States)

    Cheng, Chong-Qing; Zhang, Rui-Tao; Xiong, Yu; Chen, Li; Wang, Jian; Huang, Guo-Hua; Li, Ke-Quan; Zhang, Lian; Bai, Jin

    2015-01-01

    Abstract As a noninvasive treatment technique, ultrasound-guided high-intensity focused ultrasound (HIFU) has been considered as a routine treatment for uterine fibroids and adenomyosis in China. Contrast-enhanced ultrasound (CEUS) has been proposed as another option to assess the treatment efficacy during HIFU treatment. The aim of this investigation is to evaluate the adverse effects of HIFU ablation for benign uterine diseases in a group of patients studied with ultrasound contrast agent (UCA), in comparison with a group of patients not exposed to UCA. From November 2010 to December 2013, 2604 patients with benign uterine diseases were treated with HIFU. Among them, 1300 patients were exposed to an UCA, whereas 1304 patients were not. During HIFU procedure, the incidences of leg pain, sacral/buttock pain, groin pain, treatment area pain, and the discomfort “hot” sensation on skin were higher in the patients who were exposed to SonoVue (Bracco, Milan, Italy) than those who were not (20.5% vs 11.7%, 52.5% vs 42.3%, 6.5% vs 4.5%, 68.9% vs 55.4%, and 48.1% vs 42.9%, respectively). Among the postoperative adverse effects, the incidence of lower abdominal pain was significantly higher in patients who were exposed to an UCA than those who were not (51.2% vs 39.9%, P < 0.05). Two patients who were exposed to an UCA had acute renal function failure. In conclusion, UCA may increase the incidences of some common HIFU-related adverse effects during HIFU treatment for benign uterine diseases, but most of which were acceptable and self-limited. After HIFU treatment, renal function should be monitored in patients with a history of hypertension or taking nonsteroidal anti-inflammatory drugs. PMID:25906100

  10. Transmission electron microscopy of VX2 liver tumors after high-intensity focused ultrasound ablation enhanced with SonoVue.

    Science.gov (United States)

    Li, Qiuyang; Du, Junfeng; Yu, Ming; He, Guangbin; Luo, Wen; Li, Hongling; Zhou, Xiaodong

    2009-01-01

    The purpose of this study was to observe sequential changes in rabbit VX2 liver tumors using transmission electron microscopy after high-intensity focused ultrasound (HIFU) ablation enhanced with the contrast agent SonoVuer (Bracco, Milan, Italy). Thirty New Zealand rabbits with VX2 liver tumors were randomly divided into two groups. The liver tumors of rabbits in Group A underwent single HIFU ablation; those in Group B were given the ultrasound contrast agent SonoVue 0.2 mL/kg before HIFU exposure. Five rabbits from each of the two groups were killed at 0 hours, 6 days, and 14 days after HIFU ablation. Tissue samples that included targeted and untargeted tissue were observed using transmission electron microscopy. Using transmission electron microscopy, it was evident that most of the cellular organs in the targeted areas of tumors in Groups A and B had disappeared early after HIFU, but the basic cell structure was seen in Group A. On the sixth day after HIFU ablation, all cells in the targeted areas were disrupted, and fibrous bands were detected in the rims of targeted areas in both groups. In the surrounding areas, cell swelling in Group B was more severe than in Group A, and a greater number of apoptotic bodies were found in Group B. The use of an ultrasound contrast agent can enhance the effects of HIFU ablation on the destruction of cell ultrastructure and can enlarge the region of HIFU ablation; this provides experimental evidence for the use of contrast agents in controlling the effects of HIFU.

  11. Treatment of hepatic tumors by thermal versus mechanical effects of pulsed high intensity focused ultrasound in vivo

    Science.gov (United States)

    Peng, Song; Zhou, Ping; He, Wei; Liao, Manqiong; Chen, Lili; Ma, C.-M.

    2016-09-01

    The purpose of this study is to comparatively assess the thermal versus mechanical effects of pulsed high intensity focused ultrasound (HIFU) treatment on hepatic tumors in vivo. Forty-five rabbits with hepatic VX2 tumors were randomly separated into three groups (15 animals per group) before HIFU ablation. The total HIFU energy (in situ) of 1250 J was used for each tumor for three groups. In groups I and II, animals were treated with 1 MHz pulsed ultrasound at 1 Hz pulsed repetition frequency (PRF), 0.5 duty cycle (0.5 s on and 0.5 s off) and10 s duration for one spot sonication. For group II, in addition to HIFU treatment, microbubbles (SonoVue, Bracco, Milan, Italy) were injected via vein before sonication acting as a synergist. In group III, animals were treated with 1 MHz pulsed ultrasound at 10 Hz PRF, 0.1 duty cycle (0.1 s on and 0.9 s off) and 10 s duration for one sonication. The total treatment spots were calculated according to the tumor volume. Tumors were examined with contrast-enhanced computed tomography (CECT) immediately prior to and post HIFU treatment. Histopathologic assessment was performed 3 h after treatment. Our study showed that all animals tolerated the HIFU treatment well. Our data showed that mechanical HIFU could lead to controlled injury in rabbit hepatic tumors with different histological changes in comparison to thermal HIFU with or without microbubbles.

  12. Therapeutic response assessment of high intensity focused ultrasound therapy for uterine fibroid: Utility of contrast-enhanced ultrasonography

    International Nuclear Information System (INIS)

    Zhou Xiaodong; Ren Xiaolong; Zhang Jun; He Guangbin; Zheng Minjuan; Tian Xue; Li Li; Zhu Ting; Zhang Min; Wang Lei; Luo Wen

    2007-01-01

    Purpose: To assess the utility of contrast-enhanced ultrasonography (ceUS) in the assessment of the therapeutic response to high intensity focused ultrasound (HIFU) ablation in patients with uterine fibroid. Materials and methods: Sixty-four patients with a total of 64 uterine fibroids (mean: 5.3 ± 1.2 cm; range: 3.2-8.9 cm) treated with HIFU ablation under the ultrasound guidance were evaluated with ceUS after receiving an intravenous bolus injection of a microbubble contrast agent (SonoVue) within 1 week after intervention. We obtained serial ceUS images during the time period from beginning to 5 min after the initiation of the bolus contrast injection. All of the patients underwent a contrast enhanced MRI (ceMRI) and ultrasound guided needle puncture biopsy within 1 week after HIFU ablation. And as a follow-up, all of the patients underwent US at 1, 3, 6 and 12 months after HIFU treatment. The volume change was observed and compared to pre- and post-HIFU ablation. The results of the ceUS were compared with those of the ceMRI in terms of the presence or absence of residual unablated tumor and pathologic change in the treated lesions. Results: On ceUS, diagnostic accuracy was 100%, while residual unablated tumors were found in three uterine fibroids (4.7%) and failed treatment was found in eight uterine fibroids (12.5%). All the 11 fibroids were subjected to additional HIFU ablation. Of the 58 ablated fibroids without residual tumors on both the ceUS and ceMRI after the HIFU ablation, the volumes of all the fibroids decreased in different degrees during the 1 year follow-up USs. And histologic examinations confirmed findings of necrotic and viable tumor tissue, respectively. Conclusion: CEUS is potentially useful for evaluating the early therapeutic effect of percutaneous HIFU ablation for uterine fibroids

  13. Dynamic T{sub 2}-mapping during magnetic resonance guided high intensity focused ultrasound ablation of bone marrow

    Energy Technology Data Exchange (ETDEWEB)

    Waspe, Adam C.; Looi, Thomas; Mougenot, Charles; Amaral, Joao; Temple, Michael; Sivaloganathan, Siv; Drake, James M. [Centre for Image Guided Innovation and Therapeutic Intervention, The Hospital for Sick Children, Toronto, ON, M5G 1X8 (Canada); Philips Healthcare Canada, Markham, ON, L6C 2S3 (Canada); Centre for Image Guided Innovation and Therapeutic Intervention, The Hospital for Sick Children, Toronto, ON, M5G 1X8 (Canada); Department of Applied Mathematics, University of Waterloo, Waterloo, ON, N2L 3G1 (Canada); Centre for Image Guided Innovation and Therapeutic Intervention, The Hospital for Sick Children, Toronto, ON, M5G 1X8 (Canada)

    2012-11-28

    Focal bone tumor treatments include amputation, limb-sparing surgical excision with bone reconstruction, and high-dose external-beam radiation therapy. Magnetic resonance guided high intensity focused ultrasound (MR-HIFU) is an effective non-invasive thermotherapy for palliative management of bone metastases pain. MR thermometry (MRT) measures the proton resonance frequency shift (PRFS) of water molecules and produces accurate (<1 Degree-Sign C) and dynamic (<5s) thermal maps in soft tissues. PRFS-MRT is ineffective in fatty tissues such as yellow bone marrow and, since accurate temperature measurements are required in the bone to ensure adequate thermal dose, MR-HIFU is not indicated for primary bone tumor treatments. Magnetic relaxation times are sensitive to lipid temperature and we hypothesize that bone marrow temperature can be determined accurately by measuring changes in T{sub 2}, since T{sub 2} increases linearly in fat during heating. T{sub 2}-mapping using dual echo times during a dynamic turbo spin-echo pulse sequence enabled rapid measurement of T{sub 2}. Calibration of T{sub 2}-based thermal maps involved heating the marrow in a bovine femur and simultaneously measuring T{sub 2} and temperature with a thermocouple. A positive T{sub 2} temperature dependence in bone marrow of 20 ms/ Degree-Sign C was observed. Dynamic T{sub 2}-mapping should enable accurate temperature monitoring during MR-HIFU treatment of bone marrow and shows promise for improving the safety and reducing the invasiveness of pediatric bone tumor treatments.

  14. Feasibility of ultrasound-guided high intensity focused ultrasound ablating uterine fibroids with hyperintense on T2-weighted MR imaging

    International Nuclear Information System (INIS)

    Zhao, Wen-Peng; Chen, Jin-Yun; Zhang, Lian; Li, Quan; Qin, Juan

    2013-01-01

    Purpose: To retrospectively investigate whether uterine fibroids with hyperintense on pretreatment T2-weighted magnetic resonance imaging (MRI) could be treated with ultrasound-guided high intensity focused ultrasound (USgHIFU). Materials and methods: 282 patients with 282 symptomatic uterine fibroids who underwent USgHIFU treatment were retrospectively analyzed. Based on the signal intensity of T2-weighted MRI, uterine fibroids were classified as hypointense, isointense and hyperintense. Hyperintense fibroids were subjectively further subdivided into heterogeneous hyperintense, slightly homogeneous hyperintense and markedly homogeneous hyperintense based on the signal intensity of fibroid relative to myometrium and endometrium on T2-weighted MRI. Enhanced MRI was performed within one month after HIFU treatment. Non-perfused volume (NPV, indicative of successful ablation) ratio, treatment time, treatment efficiency, energy effect ratio and adverse events were recorded. Results: The median volume of uterine fibroids was 70.3 cm 3 (interquartile range, 41.1–132.5 cm 3 ). The average NPV ratio, defined as non-perfused volume divided by the fibroid volume after HIFU treatment, was 76.8 ± 19.0% (range, 0–100%) in the 282 patients. It was 86.3 ± 11.9% (range, 40.9–100.0%) in the group with hypointense fibroids, 77.1 ± 16.5% (range, 32.2–100.0%) in isointense fibroids, and 67.6 ± 23.9% (range, 0–100.0%) in hyperintense fibroids. The lowest NPV ratio, lowest treatment efficiency, more treatment time, more sonication energy and pain scores were observed in the slightly homogeneous hyperintense fibroids, and the NPV ratio was 55.8 ± 26.7% (range, 0–83.9%) in this subgroup. Conclusion: Based on our results, the heterogeneous and markedly homogeneous hyperintense fibroids were suitable for USgHIFU, and only the slightly homogeneous hyperintense fibroids should be excluded

  15. Assessment of Gold Nanoparticle-Mediated-Enhanced Hyperthermia Using MR-Guided High-Intensity Focused Ultrasound Ablation Procedure.

    Science.gov (United States)

    Devarakonda, Surendra B; Myers, Matthew R; Lanier, Mathew; Dumoulin, Charles; Banerjee, Rupak K

    2017-04-12

    High-intensity focused ultrasound (HIFU) has gained increasing popularity as a noninvasive therapeutic procedure to treat solid tumors. However, collateral damage due to the use of high acoustic powers during HIFU procedures remains a challenge. The objective of this study is to assess the utility of using gold nanoparticles (gNPs) during HIFU procedures to locally enhance heating at low powers, thereby reducing the likelihood of collateral damage. Phantoms containing tissue-mimicking material (TMM) and physiologically relevant concentrations (0%, 0.0625%, and 0.125%) of gNPs were fabricated. Sonications at acoustic powers of 10, 15, and 20 W were performed for a duration of 16 s using an MR-HIFU system. Temperature rises and lesion volumes were calculated and compared for phantoms with and without gNPs. For an acoustic power of 10 W, the maximum temperature rise increased by 32% and 43% for gNPs concentrations of 0.0625% and 0.125%, respectively, when compared to the 0% gNPs concentration. For the power of 15 W, a lesion volume of 0, 44.5 ± 7, and 63.4 ± 32 mm 3 was calculated for the gNPs concentration of 0%, 0.0625%, and 0.125%, respectively. For a power of 20 W, it was found that the lesion volume doubled and tripled for concentrations of 0.0625% and 0.125% gNPs, respectively, when compared to the concentration of 0% gNPs. We conclude that gNPs have the potential to locally enhance the heating and reduce damage to healthy tissue during tumor ablation using HIFU.

  16. Preliminary safety and efficacy results with robotic high-intensity focused ultrasound : A single center Indian experience

    Directory of Open Access Journals (Sweden)

    Shashikant Mishra

    2011-01-01

    Full Text Available Background : There are no Indian data of high-intensity focused ultrasound (HIFU. Being an alternative, still experimental modality, reporting short-term safety outcome is paramount. Aims : This study was aimed at to assess the safety and short-term outcome in patients with prostate cancer treated by HIFU. Settings and Design : A retrospective study of case records of 30 patients undergoing HIFU between January 2008 to September 2010 was designed and conducted. Materials and Methods : The procedural safety was analyzed at 3 months. Follow-up consisted of 3 monthly prostate-specific antigen (PSA levels and transrectal biopsy if indicated. All the patients had a minimum follow-up of 6 months. Results : A mean prostate volume of 26.9 ± 8.5 cm 3 was treated in a mean time of 115 ± 37.4 min. There was no intraoperative complication. The postoperative pain visual analogue score at day 0 was 2.1 ± 1.9 and at day 1 was 0.4 ± 0.8 on a scale of 1-10. Mean duration of perurethral catheter removal was 3.9 days. The complications after treatment were: LUTS in seven patients, stress incontinence in two, stricture in two, and symptomatic urinary tract infection in five. Average follow-up duration was 10.4 months (range, 6-20 months. Mean time to obtain PSA nadir was 6 ± 3 months with a median PSA nadir value of 0.3 ng/ml. Two patients had positive prostatic biopsy in the localized (high risk group. Conclusions : HIFU was safe in carcinoma prostate patients. The short-term results were efficacious in localized disease. The low complication rates and favorable functional outcome support the planning of further larger studies.

  17. Proton Therapy as Salvage Treatment for Local Relapse of Prostate Cancer Following Cryosurgery or High-Intensity Focused Ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Holtzman, Adam L. [University of Florida Health Proton Therapy Institute, University of Florida College of Medicine, Jacksonville, Florida (United States); Hoppe, Bradford S., E-mail: bhoppe@floridaproton.org [University of Florida Health Proton Therapy Institute, University of Florida College of Medicine, Jacksonville, Florida (United States); Letter, Haley P.; Bryant, Curtis; Nichols, Romaine C.; Henderson, Randal H.; Mendenhall, William M.; Morris, Christopher G. [University of Florida Health Proton Therapy Institute, University of Florida College of Medicine, Jacksonville, Florida (United States); Williams, Christopher R. [Department of Surgery, University of Florida College of Medicine, Jacksonville, Florida (United States); Li, Zuofeng; Mendenhall, Nancy P. [University of Florida Health Proton Therapy Institute, University of Florida College of Medicine, Jacksonville, Florida (United States)

    2016-05-01

    Purpose: Local recurrence of prostate cancer after cryosurgery (CS) and high-intensity focused ultrasound (HIFU) is an emerging problem for which optimal management is unknown. Proton therapy (PT) may offer advantages over other local therapeutic options. This article reviews a single institution's experience using PT for salvage of local recurrent disease after HIFU or CS. Methods and Materials: We reviewed the medical records of 21 consecutive patients treated with salvage PT following a local recurrence of prostate cancer after CS (n=12) or HIFU (n=9) between January 2007 and July 2014. Patients were treated to a median dose of 74 Gy(relative biological effectiveness [RBE]; range: 74-82 Gy[RBE]) and 8 patients received androgen deprivation therapy with radiation therapy. Patients were evaluated for quality of life (QOL) by using the Expanded Prostate Index Composite questionnaire and toxicity by using Common Terminology Criteria for Adverse Events, version 3.0, weekly during treatment, every 6 months for 2 years after treatment, and then annually. Results: Median follow-up was 37 months (range: 6-95 months). The 3-year biochemical progression-free survival (bPFS) rate was 77%. The 3-year grade 3 toxicity rate was 17%; however, 2 of these patients had pre-existing grade 3 GU toxicities from their HIFU/CRYO prior to PT. At 1 year, bowel summary, urinary incontinence, and urinary obstructive QOL scores declined, but only the bowel QOL score at 12 months met the minimally important difference threshold. Conclusions: PT achieved a high rate of bPFS with acceptable toxicity and minimal changes in QOL scores compared with baseline pre-PT functions. Although most patients have done fairly well, the study size is small, follow-up is short, and early results suggest that outcomes with PT for salvage after HIFU or CS failure are inferior to outcomes with PT given in the de novo setting with respect to disease control, toxicity, and QOL.

  18. Magnetic Resonance–Guided High-Intensity Focused Ultrasound Hyperthermia for Recurrent Rectal Cancer: MR Thermometry Evaluation and Preclinical Validation

    Energy Technology Data Exchange (ETDEWEB)

    Chu, William, E-mail: William.Chu@sunnybrook.ca [Department of Radiation Oncology, Sunnybrook Health Sciences Centre and the University of Toronto, Toronto, Ontario (Canada); Physical Sciences, Sunnybrook Research Institute, Toronto, Ontario (Canada); Staruch, Robert M. [Clinical Sites Research Program, Philips Research, Cambridge, Massachusetts (United States); Pichardo, Samuel [Thunder Bay Regional Research Institute, Thunder Bay, Ontario (Canada); Physics and Electrical Engineering, Lakehead University, Thunder Bay, Ontario (Canada); Tillander, Matti; Köhler, Max O. [MR Therapy, Philips Healthcare, Vantaa (Finland); Huang, Yuexi [Physical Sciences, Sunnybrook Research Institute, Toronto, Ontario (Canada); Ylihautala, Mika [MR Therapy, Philips Healthcare, Vantaa (Finland); McGuffin, Merrylee [Department of Radiation Oncology, Sunnybrook Health Sciences Centre and the University of Toronto, Toronto, Ontario (Canada); Czarnota, Gregory [Department of Radiation Oncology, Sunnybrook Health Sciences Centre and the University of Toronto, Toronto, Ontario (Canada); Physical Sciences, Sunnybrook Research Institute, Toronto, Ontario (Canada); Hynynen, Kullervo [Physical Sciences, Sunnybrook Research Institute, Toronto, Ontario (Canada)

    2016-07-15

    Purpose: To evaluate the feasibility of magnetic resonance–guided high-intensity focused ultrasound (MR-HIFU) mild hyperthermia in deep tissue targets for enhancing radiation therapy and chemotherapy in the context of recurrent rectal cancer. A preclinical study was performed to evaluate the safety and performance of MR-HIFU mild hyperthermia. A prospective imaging study was performed in volunteers with rectal cancer to evaluate MR thermometry quality near the rectum and accessibility of rectal tumors using MR-HIFU. Methods and Materials: Mild hyperthermia was performed in pig thigh (9 sonications, 6 pigs) using a clinical MR-HIFU system. Targets near the rectal wall and deep thigh were evaluated. Thermal maps obtained in 6 planes every 3.2 seconds were used to control sonications in 18-mm diameter treatment regions at temperatures of 42°C to 42.5°C for 10 to 60 minutes. Volunteer imaging-only studies to assess the quality of MR thermometry (without heating) were approved by the institutional research ethics board. Anatomic and MR thermometry images were acquired in consenting volunteers with rectal cancer. In 3 of 6 study participants, rectal filling with saline was used to reduce motion-related MR thermometry artifacts near the tumor. Results: In pigs, mean target temperature matched the desired hyperthermia temperature within 0.2°C; temporal standard deviation ≤0.5°C. With optimized control thresholds, no undesired tissue damage was observed. In human volunteers, MR temperature measurements had adequate precision and stability, especially when rectal filling was used to reduce bowel motion. Conclusions: In pigs, MR-HIFU can safely deliver mild hyperthermia (41°C-43°C) to a targeted volume for 30 minutes. In humans, careful patient selection and preparation will enable adequate targeting for recurrent rectal cancers and sufficient MR temperature mapping stability to control mild hyperthermia. These results enable human trials of MR-HIFU hyperthermia.

  19. Real-time monitoring of high-intensity focused ultrasound treatment using axial strain and axial-shear strain elastograms.

    Science.gov (United States)

    Xia, Rongmin; Thittai, Arun K

    2014-03-01

    Axial strain elastograms (ASEs) have been found to help visualize sonographically invisible thermal lesions. However, in most studies involving high-intensity focused ultrasound (HIFU)-induced thermal lesions, elastography imaging was performed separately later, after the lesion was formed. In this article, the feasibility of monitoring, in real time, tissue elasticity variation during HIFU treatment and immediately thereafter is explored using quasi-static elastography. Further, in addition to ASEs, we also explore the use of simultaneously acquired axial-shear strain elastograms (ASSEs) for HIFU lesion visualization. Experiments were performed on commercial porcine liver samples in vitro. The HIFU experiments were conducted at two applied acoustic power settings, 35 and 20 W. The experimental setup allowed us to interrupt the HIFU pulse momentarily several different times during treatment to perform elastographic compression and data acquisition. At the end of the experiments, the samples were cut along the imaging plane and photographed to compare size and location of the formed lesion with those visualized on ASEs and ASSEs. Single-lesion and multiple-lesion experiments were performed to assess the contribution of ASEs and ASSEs to lesion visualization and treatment monitoring tasks. At both power settings, ASEs and ASSEs provided accurate location information during HIFU treatment. At the low-power setting case, ASEs and ASSEs provide accurate lesion size in real-time monitoring. Lesion appearance in ASEs and ASSEs was affected by the cavitation bubbles produced at the high-power setting. The results further indicate that the cavitation bubbles influence lesion appearance more in ASEs than in ASSEs. Both ASEs and ASSEs provided accurate size information after a waiting period that allowed the cavitation bubbles to disappear. The results indicate that ASSEs not only improve lesion visualization and size measurement of a single lesion, but, under certain

  20. Proton Therapy as Salvage Treatment for Local Relapse of Prostate Cancer Following Cryosurgery or High-Intensity Focused Ultrasound

    International Nuclear Information System (INIS)

    Holtzman, Adam L.; Hoppe, Bradford S.; Letter, Haley P.; Bryant, Curtis; Nichols, Romaine C.; Henderson, Randal H.; Mendenhall, William M.; Morris, Christopher G.; Williams, Christopher R.; Li, Zuofeng; Mendenhall, Nancy P.

    2016-01-01

    Purpose: Local recurrence of prostate cancer after cryosurgery (CS) and high-intensity focused ultrasound (HIFU) is an emerging problem for which optimal management is unknown. Proton therapy (PT) may offer advantages over other local therapeutic options. This article reviews a single institution's experience using PT for salvage of local recurrent disease after HIFU or CS. Methods and Materials: We reviewed the medical records of 21 consecutive patients treated with salvage PT following a local recurrence of prostate cancer after CS (n=12) or HIFU (n=9) between January 2007 and July 2014. Patients were treated to a median dose of 74 Gy(relative biological effectiveness [RBE]; range: 74-82 Gy[RBE]) and 8 patients received androgen deprivation therapy with radiation therapy. Patients were evaluated for quality of life (QOL) by using the Expanded Prostate Index Composite questionnaire and toxicity by using Common Terminology Criteria for Adverse Events, version 3.0, weekly during treatment, every 6 months for 2 years after treatment, and then annually. Results: Median follow-up was 37 months (range: 6-95 months). The 3-year biochemical progression-free survival (bPFS) rate was 77%. The 3-year grade 3 toxicity rate was 17%; however, 2 of these patients had pre-existing grade 3 GU toxicities from their HIFU/CRYO prior to PT. At 1 year, bowel summary, urinary incontinence, and urinary obstructive QOL scores declined, but only the bowel QOL score at 12 months met the minimally important difference threshold. Conclusions: PT achieved a high rate of bPFS with acceptable toxicity and minimal changes in QOL scores compared with baseline pre-PT functions. Although most patients have done fairly well, the study size is small, follow-up is short, and early results suggest that outcomes with PT for salvage after HIFU or CS failure are inferior to outcomes with PT given in the de novo setting with respect to disease control, toxicity, and QOL.

  1. Intrapleural fluid infusion for MR-guided high-intensity focused ultrasound ablation in the liver dome.

    Science.gov (United States)

    Wijlemans, Joost W; de Greef, Martijn; Schubert, Gerald; Moonen, Chrit T W; van den Bosch, Maurice A A J; Ries, Mario

    2014-12-01

    Magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) ablation of tumors in the liver dome is challenging because of the presence of air in the costophrenic angle. In this study, we used a porcine liver model and a clinical MR-HIFU system to assess the feasibility and safety of using intrapleural fluid infusion (IPI) to create an acoustic window for MR-HIFU ablation in the liver dome. Healthy adult Dalland land pigs (n = 6) under general anesthesia were used with animal committee approval. Degassed saline (200-800 mL) was infused into the intrapleural space under ultrasound guidance. A clinical 1.5-T MR-HIFU system was used to perform sonications (4-mm treatment cells, 300-450 W, 20-30 seconds) in the liver dome under real-time MR thermometry. An intercostal firing technique was used to prevent rib heating in one experiment. Technical success was defined as a temperature increase (>10°C) in the target area. After termination, the animal was examined for thermal damage to liver, diaphragm, pleura, lung, or intercostal muscle. An acoustic window was established in all animals. A temperature increase in the target area was achieved in all animals (max. 47°C-67°C). MR thermometry showed no heating outside the target area. Intercostal firing effectively reduced rib heating (55°C vs. 42°C). Postmortem examination revealed no unwanted thermal damage. One complication occurred, in the first experiment, because of an ill-suited needle (displacement of the needle). The results indicate that IPI may be used safely to assist MR-HIFU ablation of tumors in the liver dome. For reliable tissue coagulation, IPI must be combined with an intercostal sonication technique. Considering the proportion of patients with tumors in the liver dome, IPI widens the applicability of MR-HIFU ablation for liver tumors considerably. Copyright © 2014 AUR. Published by Elsevier Inc. All rights reserved.

  2. Boiling histotripsy lesion characterization on a clinical magnetic resonance imaging-guided high intensity focused ultrasound system.

    Directory of Open Access Journals (Sweden)

    Avinash Eranki

    Full Text Available High intensity focused ultrasound (HIFU is a non-invasive therapeutic technique that can thermally ablate tumors. Boiling histotripsy (BH is a HIFU approach that can emulsify tissue in a few milliseconds. Lesion volume and temperature effects for different BH sonication parameters are currently not well characterized. In this work, lesion volume, temperature distribution, and area of lethal thermal dose were characterized for varying BH sonication parameters in tissue-mimicking phantoms (TMP and demonstrated in ex vivo tissues.The following BH sonication parameters were varied using a clinical MR-HIFU system (Sonalleve V2, Philips, Vantaa, Finland: acoustic power, number of cycles/pulse, total sonication time, and pulse repetition frequency (PRF. A 3×3×3 pattern was sonicated inside TMP's and ex vivo tissues. Post sonication, lesion volumes were quantified using 3D ultrasonography and temperature and thermal dose distributions were analyzed offline. Ex vivo tissues were sectioned and stained with H&E post sonication to assess tissue damage.Significant increase in lesion volume was observed while increasing the number of cycles/pulse and PRF. Other sonication parameters had no significant effect on lesion volume. Temperature full width at half maximum at the end of sonication increased significantly with all parameters except total sonication time. Positive correlation was also found between lethal thermal dose and lesion volume for all parameters except number of cycles/pulse. Gross pathology of ex vivo tissues post sonication displayed either completely or partially damaged tissue at the focal region. Surrounding tissues presented sharp boundaries, with little or no structural damage to adjacent critical structures such as bile duct and nerves.Our characterization of effects of HIFU sonication parameters on the resulting lesion demonstrates the ability to control lesion morphologic and thermal characteristics with a clinical MR-HIFU system in

  3. Effects of magnetic resonance-guided high-intensity focused ultrasound ablation on bone mechanical properties and modeling.

    Science.gov (United States)

    Yeo, Sin Yuin; Arias Moreno, Andrés J; van Rietbergen, Bert; Ter Hoeve, Natalie D; van Diest, Paul J; Grüll, Holger

    2015-01-01

    Magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) is a promising technique for palliative treatment of bone pain. In this study, the effects of MR-HIFU ablation on bone mechanics and modeling were investigated. A total of 12 healthy rat femurs were ablated using 10 W for 46 ± 4 s per sonication with 4 sonications for each femur. At 7 days after treatments, all animals underwent MR and single photon emission computed tomography/computed tomography (SPECT/CT) imaging. Then, six animals were euthanized. At 1 month following ablations, the remaining six animals were scanned again with MR and SPECT/CT prior to euthanization. Thereafter, both the HIFU-treated and contralateral control bones of three animals from each time interval were processed for histology, whereas the remaining bones were subjected to micro-CT (μCT), three-point bending tests, and micro-finite element (micro-FE) analyses. At 7 days after HIFU ablations, edema formation around the treated bones coupled with bone marrow and cortical bone necrosis was observed on MRI and histological images. SPECT/CT and μCT images revealed presence of bone modeling through an increased uptake of (99m)Tc-MDP and formation of woven bone, respectively. At 31 days after ablations, as illustrated by imaging and histology, healing of the treated bone and the surrounding soft tissue was noted, marked by decreased in amount of tissue damage, formation of scar tissue, and sub-periosteal reaction. The results of three-point bending tests showed no significant differences in elastic stiffness, ultimate load, and yield load between the HIFU-treated and contralateral control bones at 7 days and 1 month after treatments. Similarly, the elastic stiffness and Young's moduli determined by micro-FE analyses at both time intervals were not statistically different. Multimodality imaging and histological data illustrated the presence of HIFU-induced bone damage at the cellular level, which activated the

  4. Focusing and transport of high-intensity multi-MeV proton bunches from a compact laser-driven source

    Science.gov (United States)

    Busold, S.; Schumacher, D.; Deppert, O.; Brabetz, C.; Frydrych, S.; Kroll, F.; Joost, M.; Al-Omari, H.; Blažević, A.; Zielbauer, B.; Hofmann, I.; Bagnoud, V.; Cowan, T. E.; Roth, M.

    2013-10-01

    Laser ion acceleration provides for compact, high-intensity ion sources in the multi-MeV range. Using a pulsed high-field solenoid, for the first time high-intensity laser-accelerated proton bunches could be selected from the continuous exponential spectrum and delivered to large distances, containing more than 109 particles in a narrow energy interval around a central energy of 9.4 MeV and showing ≤30mrad envelope divergence. The bunches of only a few nanoseconds bunch duration were characterized 2.2 m behind the laser-plasma source with respect to arrival time, energy width, and intensity as well as spatial and temporal bunch profile.

  5. Focusing and transport of high-intensity multi-MeV proton bunches from a compact laser-driven source

    Directory of Open Access Journals (Sweden)

    S. Busold

    2013-10-01

    Full Text Available Laser ion acceleration provides for compact, high-intensity ion sources in the multi-MeV range. Using a pulsed high-field solenoid, for the first time high-intensity laser-accelerated proton bunches could be selected from the continuous exponential spectrum and delivered to large distances, containing more than 10^{9} particles in a narrow energy interval around a central energy of 9.4 MeV and showing ≤30  mrad envelope divergence. The bunches of only a few nanoseconds bunch duration were characterized 2.2 m behind the laser-plasma source with respect to arrival time, energy width, and intensity as well as spatial and temporal bunch profile.

  6. Single session of high-intensity focused ultrasound therapy for the management of organ-confined prostate cancer: A single-institute experience

    Directory of Open Access Journals (Sweden)

    Yu-Cing Juho

    2016-12-01

    Conclusion: High-intensity focused ultrasound is an alternative therapy for patients with localized prostate cancer. In combination with preceding transurethral resection of the prostate, this treatment shows promise in disease control with a low complication rate in short-term follow-up.

  7. Cluster analysis of DCE-MRI data identifies regional tracer-kinetic changes after tumor treatment with high intensity focused ultrasound

    NARCIS (Netherlands)

    Jacobs, Igor; Hectors, Stefanie J. C. G.; Schabel, Matthias C.; Grüll, Holger; Strijkers, Gustav J.; Nicolay, Klaas

    2015-01-01

    Evaluation of high intensity focused ultrasound (HIFU) treatment with MRI is generally based on assessment of the non-perfused volume from contrast-enhanced T1-weighted images. However, the vascular status of tissue surrounding the non-perfused volume has not been extensively investigated with MRI.

  8. The contemporary role of ablative treatment approaches in the management of renal cell carcinoma (RCC): focus on radiofrequency ablation (RFA), high-intensity focused ultrasound (HIFU), and cryoablation.

    Science.gov (United States)

    Klatte, Tobias; Kroeger, Nils; Zimmermann, Uwe; Burchardt, Martin; Belldegrun, Arie S; Pantuck, Allan J

    2014-06-01

    Currently, most of renal tumors are small, low grade, with a slow growth rate, a low metastatic potential, and with up to 30 % of these tumors being benign on the final pathology. Moreover, they are often diagnosed in elderly patients with preexisting medical comorbidities in whom the underlying medical conditions may pose a greater risk of death than the small renal mass. Concerns regarding overdiagnosis and overtreatment of patients with indolent small renal tumors have led to an increasing interest in minimally invasive, ablative as an alternative to extirpative interventions for selected patients. To provide an overview about the state of the art in radiofrequency ablation (RFA), high-intensity focused ultrasound, and cryoablation in the clinical management of renal cell carcinoma. A PubMed wide the literature search of was conducted. International consensus panels recommend ablative techniques in patients who are unfit for surgery, who are not considered candidates for or elect against elective surveillance, and who have small renal masses. The most often used techniques are cryoablation and RFA. These ablative techniques offer potentially curative outcomes while conferring several advantages over extirpative surgery, including improved patient procedural tolerance, faster recovery, preservation of renal function, and reduction in the risk of intraoperative and postsurgical complications. While it is likely that outcomes associated with ablative modalities will improve with further advances in technology, their application will expand to more elective indications as longer-term efficacy data become available. Ablative techniques pose a valid treatment option in selected patients.

  9. High intensity circular proton accelerators

    International Nuclear Information System (INIS)

    Craddock, M.K.

    1987-12-01

    Circular machines suitable for the acceleration of high intensity proton beams include cyclotrons, FFAG accelerators, and strong-focusing synchrotrons. This paper discusses considerations affecting the design of such machines for high intensity, especially space charge effects and the role of beam brightness in multistage accelerators. Current plans for building a new generation of high intensity 'kaon factories' are reviewed. 47 refs

  10. The 'Critical Power' Concept: Applications to Sports Performance with a Focus on Intermittent High-Intensity Exercise.

    Science.gov (United States)

    Jones, Andrew M; Vanhatalo, Anni

    2017-03-01

    The curvilinear relationship between power output and the time for which it can be sustained is a fundamental and well-known feature of high-intensity exercise performance. This relationship 'levels off' at a 'critical power' (CP) that separates power outputs that can be sustained with stable values of, for example, muscle phosphocreatine, blood lactate, and pulmonary oxygen uptake ([Formula: see text]), from power outputs where these variables change continuously with time until their respective minimum and maximum values are reached and exercise intolerance occurs. The amount of work that can be done during exercise above CP (the so-called W') is constant but may be utilized at different rates depending on the proximity of the exercise power output to CP. Traditionally, this two-parameter CP model has been employed to provide insights into physiological responses, fatigue mechanisms, and performance capacity during continuous constant power output exercise in discrete exercise intensity domains. However, many team sports (e.g., basketball, football, hockey, rugby) involve frequent changes in exercise intensity and, even in endurance sports (e.g., cycling, running), intensity may vary considerably with environmental/course conditions and pacing strategy. In recent years, the appeal of the CP concept has been broadened through its application to intermittent high-intensity exercise. With the assumptions that W' is utilized during work intervals above CP and reconstituted during recovery intervals below CP, it can be shown that performance during intermittent exercise is related to four factors: the intensity and duration of the work intervals and the intensity and duration of the recovery intervals. However, while the utilization of W' may be assumed to be linear, studies indicate that the reconstitution of W' may be curvilinear with kinetics that are highly variable between individuals. This has led to the development of a new CP model for intermittent exercise in

  11. Multi-parametric monitoring and assessment of High Intensity Focused Ultrasound (HIFU) boiling by Harmonic Motion Imaging for Focused Ultrasound (HMIFU): An ex vivo feasibility study

    Science.gov (United States)

    Hou, Gary Y.; Marquet, Fabrice; Wang, Shutao; Konofagou, Elisa E.

    2014-01-01

    Harmonic Motion Imaging for Focused Ultrasound (HMIFU) is a recently developed high-intensity focused ultrasound (HIFU) treatment monitoring method with feasibilities demonstrated in vitro and in vivo. Here, a multi-parametric study is performed to investigate both elastic and acoustics-independent viscoelastic tissue changes using the Harmonic Motion Imaging (HMI) displacement, axial compressive strain and change in relative phase-shift during high energy HIFU treatment with tissue boiling. Forty three (n=43) thermal lesions were formed in ex vivo canine liver specimens (n=28). Two dimensional (2D) transverse HMI displacement maps were also obtained before and after lesion formation. The same method was repeated in 10-s, 20-s and 30-s HIFU durations at three different acoustic powers of 8, 10, and 11W, which were selected and verified as treatment parameters capable of inducing boiling using both thermocouple and Passive Cavitation Detection (PCD) measurements. Although a steady decrease in the displacement, compressive strain, and relative change in the focal phase shift (Δφ) were obtained in numerous cases, indicating an overall increase in relative stiffness, the study outcomes also showed that during boiling, a reverse lesion-to-background displacement contrast was detected, indicating potential change in tissue absorption, geometrical change and/or, mechanical gelatification or pulverization. Following treatment, corresponding 2D HMI displacement images of the thermal lesions also mapped consistent discrepancy in the lesion-to-background displacement contrast. Despite unpredictable changes in acoustic properties with boiling, the relative change in phase shift showed a consistent decrease, indicating its robustness to monitor biomechanical properties independent of the acoustic property change throughout the HIFU treatment. In addition, the 2D HMI displacement images confirmed and indicated the increase in the thermal lesion size with treatment duration

  12. Multi-parametric monitoring and assessment of high-intensity focused ultrasound (HIFU) boiling by harmonic motion imaging for focused ultrasound (HMIFU): an ex vivo feasibility study.

    Science.gov (United States)

    Hou, Gary Y; Marquet, Fabrice; Wang, Shutao; Konofagou, Elisa E

    2014-03-07

    Harmonic motion imaging for focused ultrasound (HMIFU) is a recently developed high-intensity focused ultrasound (HIFU) treatment monitoring method with feasibilities demonstrated in vitro and in vivo. Here, a multi-parametric study is performed to investigate both elastic and acoustics-independent viscoelastic tissue changes using the Harmonic Motion Imaging (HMI) displacement, axial compressive strain and change in relative phase shift during high energy HIFU treatment with tissue boiling. Forty three (n = 43) thermal lesions were formed in ex vivo canine liver specimens (n = 28). Two-dimensional (2D) transverse HMI displacement maps were also obtained before and after lesion formation. The same method was repeated in 10 s, 20 s and 30 s HIFU durations at three different acoustic powers of 8, 10, and 11 W, which were selected and verified as treatment parameters capable of inducing boiling using both thermocouple and passive cavitation detection (PCD) measurements. Although a steady decrease in the displacement, compressive strain, and relative change in the focal phase shift (Δϕ) were obtained in numerous cases, indicating an overall increase in relative stiffness, the study outcomes also showed that during boiling, a reverse lesion-to-background displacement contrast was detected, indicating potential change in tissue absorption, geometrical change and/or, mechanical gelatification or pulverization. Following treatment, corresponding 2D HMI displacement images of the thermal lesions also mapped consistent discrepancy in the lesion-to-background displacement contrast. Despite the expectedly chaotic changes in acoustic properties with boiling, the relative change in phase shift showed a consistent decrease, indicating its robustness to monitor biomechanical properties independent of the acoustic property changes throughout the HIFU treatment. In addition, the 2D HMI displacement images confirmed and indicated the increase in the thermal lesion size with

  13. Transrectal high-intensity focused ultrasound (HIFU) treatment of localized prostate cancer: Review of technical incidents and morbidity after 5 years of use

    OpenAIRE

    RIPERT, Thomas; AZEMAR, Marie Dominique; MENARD, Johann; BAYOUD, Younes; MESSAOUDI, Rabah; DUVAL, François; STAERMAN, Frédéric

    2010-01-01

    Abstract OBJECTIVE To report on technical incidents, and early and late complications, occurring on high-intensity focused ultrasound (HIFU) treatment of patients with localized prostate cancer. PATIENTS AND METHODS We performed a retrospective review of patients who were treated by Ablatherm? in our centre. We recorded all technical incidents, treatment discontinuations, and early (< 1 month) and late complications. RESULTS A total of 74 HIFU procedures were perfor...

  14. Sequential transcatheter arterial chemoembolization, three-dimensional conformal radiotherapy, and high-intensity focused ultrasound treatment for unresectable hepatocellular carcinoma patients

    OpenAIRE

    Ni, Shengfa; Liu, Lingxiang; Shu, Yongqian

    2012-01-01

    The purpose of this study was to evaluate the outcome of patients with unresectable hepatocellular carcinoma (HCC) treated by sequential therapy of transcatheter arterial chemoembolization (TACE), three-dimensional conformal radiotherapy (3-DCRT) and high-intensity focused ultrasound (HIFU). From October, 2005 to September, 2010, 120 patients with unresectable HCC received the sequential treatments of several courses of TACE followed in 2-4 weeks by 3-DCRT and then a single session of HIFU wi...

  15. Magnetic Resonance-Guided High-Intensity-Focused Ultrasound for Palliation of Painful Skeletal Metastases: A Pilot Study.

    Science.gov (United States)

    Chan, Michael; Dennis, Kristopher; Huang, Yuexi; Mougenot, Charles; Chow, Edward; DeAngelis, Carlo; Coccagna, Jennifer; Sahgal, Arjun; Hynynen, Kullervo; Czarnota, Gregory; Chu, William

    2017-10-01

    Bone is one of the most common sites of metastases, with bone metastases-related pain representing a significant source of morbidity among patients with cancer. Magnetic resonance-guided focused ultrasound is a noninvasive, outpatient modality with the potential for treating painful bone metastases. The aim of this study is to report our initial experience with magnetic resonance-guided focused ultrasound in the treatment of bone metastases and our preliminary analysis of urinary cytokine levels after therapy. This was a single-center pilot study of 10 patients with metastatic cancer to investigate the feasibility of magnetic resonance-guided focused ultrasound for primary pain control in device-accessible skeletal metastases. Treatments were performed on a clinical magnetic resonance-guided focused ultrasound system using a volumetric ablation technique. Primary efficacy was assessed using Brief Pain Inventory scores and morphine equivalent daily dose intake at 3 time points: before, day 14, and day 30 after the magnetic resonance-guided focused ultrasound treatment. Urine cytokines were measured 3 days before treatment and 2 days after the treatment. Of the 10 patients, 8 were followed up 14 days and 6 were followed up 30 days after the treatment. At day 14, 3 patients (37.5%) exhibited partial pain response and 4 patients (50%) exhibited an indeterminate response, and at day 30 after the treatment, 5 patients (83%) exhibited partial pain response. No treatment-related adverse events were recorded. Of the urine cytokines measured, only Transforming growth factor alpha (TGFα) demonstrated an overall decrease, with a trend toward statistical significance ( P = .078). Our study corroborates magnetic resonance-guided focused ultrasound as a feasible and safe modality as a primary, palliative treatment for painful bone metastases and contributes to the limited body of literature using magnetic resonance-guided focused ultrasound for this clinical indication.

  16. MR-guided pulsed high intensity focused ultrasound enhancement of docetaxel combined with radiotherapy for prostate cancer treatment

    International Nuclear Information System (INIS)

    Mu Zhaomei; Ma, C-M; Chen Xiaoming; Cvetkovic, Dusica; Chen Lili; Pollack, Alan

    2012-01-01

    The purpose of this study is to evaluate the efficacy of the enhancement of docetaxel by pulsed focused ultrasound (pFUS) in combination with radiotherapy (RT) for treatment of prostate cancer in vivo. LNCaP cells were grown in the prostates of male nude mice. When the tumors reached a designated volume by MRI, tumor bearing mice were randomly divided into seven groups (n = 5): (1) pFUS alone; (2) RT alone; (3) docetaxel alone; (4) docetaxel + pFUS; (5) docetaxel + RT; (6) docetaxel + pFUS + RT, and (7) control. MR-guided pFUS treatment was performed using a focused ultrasound treatment system (InSightec ExAblate 2000) with a 1.5T GE MR scanner. Animals were treated once with pFUS, docetaxel, RT or their combinations. Docetaxel was given by i.v. injection at 5 mg kg −1 before pFUS. RT was given 2 Gy after pFUS. Animals were euthanized 4 weeks after treatment. Tumor volumes were measured on MRI at 1 and 4 weeks post-treatment. Results showed that triple combination therapies of docetaxel, pFUS and RT provided the most significant tumor growth inhibition among all groups, which may have potential for the treatment of prostate cancer due to an improved therapeutic ratio. (paper)

  17. Effect of high-intensity focused ultrasound (HIFU combined with radiotherapy on tumor malignancy in patients with advanced pancreatic cancer and evaluation of side effects

    Directory of Open Access Journals (Sweden)

    Jing Li

    2017-02-01

    Full Text Available Objective: To study the effect of high-intensity focused ultrasound (HIFU combined with radiotherapy on tumor malignancy in patients with advanced pancreatic cancer and the corresponding side effects. Methods: A total of 84 patients with advanced pancreatic cancer treated in our hospital between May 2013 and March 2016 were selected and randomly divided into HIFU group and IGRT group, HIFU group accepted high-intensity focused ultrasound combined with radiotherapy and IGRT group received radiotherapy alone. 4 weeks after treatment, the levels of tumor markers, liver and kidney function indexes, perineural invasionrelated molecules and cytokines in serum as well as the levels of immune cells in peripheral blood were determined. Results: 4 weeks after treatment, serum CA199, CA242, OPN, NGAL, RBP4, NGF, TrkA, p75, BDNF and TrkB levels of HIFU group were significantly lower than those of IGRT group, serum IL-2, TNF-毩, IFN-γ and IL-13 levels as well as peripheral blood NKT cell and CD4+T cell levels were significantly higher than those of IGRT group, and serum ALT, AST, Cr and BUN levels were not significantly different from those of IGRT group. Conclusion: HIFU combined with radiotherapy treatment of advanced pancreatic cancer can more effectively kill cancer cells, inhibit pancreatic cancer cell invasion to the peripheral nerve and enhance the antitumor immune response mediated by NKT cells and CD4+T cells.

  18. MO-AB-210-00: Diagnostic Ultrasound Imaging Quality Control and High Intensity Focused Ultrasound Therapy Hands-On Workshop

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-06-15

    The goal of this ultrasound hands-on workshop is to demonstrate advancements in high intensity focused ultrasound (HIFU) and to demonstrate quality control (QC) testing in diagnostic ultrasound. HIFU is a therapeutic modality that uses ultrasound waves as carriers of energy. HIFU is used to focus a beam of ultrasound energy into a small volume at specific target locations within the body. The focused beam causes localized high temperatures and produces a well-defined regions of necrosis. This completely non-invasive technology has great potential for tumor ablation and targeted drug delivery. At the workshop, attendees will see configurations, applications, and hands-on demonstrations with on-site instructors at separate stations. The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. At the workshop, an array of ultrasound testing phantoms and ultrasound scanners will be provided for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations of the techniques. Target audience: Medical physicists and other medical professionals in diagnostic imaging and radiation oncology with interest in high-intensity focused ultrasound and in diagnostic ultrasound QC. Learning Objectives: Learn ultrasound physics and safety for HIFU applications through live demonstrations Get an overview of the state-of-the art in HIFU technologies and equipment Gain familiarity with common elements of a quality control program for diagnostic ultrasound imaging Identify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools List of supporting vendors for HIFU and diagnostic ultrasound QC hands-on workshop: Philips Healthcare Alpinion Medical Systems Verasonics, Inc Zonare Medical Systems, Inc Computerized Imaging Reference Systems (CIRS), Inc. GAMMEX, Inc., Cablon Medical BV Steffen Sammet: NIH/NCI grant 5R25CA132822, NIH/NINDS grant 5R25NS

  19. MO-AB-210-00: Diagnostic Ultrasound Imaging Quality Control and High Intensity Focused Ultrasound Therapy Hands-On Workshop

    International Nuclear Information System (INIS)

    2015-01-01

    The goal of this ultrasound hands-on workshop is to demonstrate advancements in high intensity focused ultrasound (HIFU) and to demonstrate quality control (QC) testing in diagnostic ultrasound. HIFU is a therapeutic modality that uses ultrasound waves as carriers of energy. HIFU is used to focus a beam of ultrasound energy into a small volume at specific target locations within the body. The focused beam causes localized high temperatures and produces a well-defined regions of necrosis. This completely non-invasive technology has great potential for tumor ablation and targeted drug delivery. At the workshop, attendees will see configurations, applications, and hands-on demonstrations with on-site instructors at separate stations. The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. At the workshop, an array of ultrasound testing phantoms and ultrasound scanners will be provided for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations of the techniques. Target audience: Medical physicists and other medical professionals in diagnostic imaging and radiation oncology with interest in high-intensity focused ultrasound and in diagnostic ultrasound QC. Learning Objectives: Learn ultrasound physics and safety for HIFU applications through live demonstrations Get an overview of the state-of-the art in HIFU technologies and equipment Gain familiarity with common elements of a quality control program for diagnostic ultrasound imaging Identify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools List of supporting vendors for HIFU and diagnostic ultrasound QC hands-on workshop: Philips Healthcare Alpinion Medical Systems Verasonics, Inc Zonare Medical Systems, Inc Computerized Imaging Reference Systems (CIRS), Inc. GAMMEX, Inc., Cablon Medical BV Steffen Sammet: NIH/NCI grant 5R25CA132822, NIH/NINDS grant 5R25NS

  20. Feasibility of magnetic resonance imaging-guided high intensity focused ultrasound therapy for ablating uterine fibroids in patients with bowel lies anterior to uterus

    International Nuclear Information System (INIS)

    Zhang Lian; Chen Wenzhi; Liu Yinjiang; Hu Xiao; Zhou Kun; Chen Li; Peng Song; Zhu Hui; Zou Huiling; Bai Jin; Wang Zhibiao

    2010-01-01

    Purpose: To prospectively evaluate the feasibility of magnetic resonance (MR) imaging-guided high intensity focused ultrasound (HIFU) therapeutic ablation of uterine fibroids in patients with bowel lies anterior to uterus. Materials and methods: Twenty-one patients with 23 uterine fibroids underwent MR imaging-guided high intensity focused ultrasound treatment, with a mean age of 39.4 ± 6.9 (20-49) years, with fibroids average measuring 6.0 ± 1.6 (range, 2.9-9.5) cm in diameter. After being compressed with a degassed water balloon on abdominal wall, MR imaging-guided high intensity focused ultrasound treatment was performed under conscious sedation by using fentanyl and midazolam. This procedure was performed by a Haifu JM focused ultrasound tumour therapeutic system (JM2.5C, Chongqing Haifu Technology Co., Ltd., China), in combination with a 1.5-Tesla MRI system (Symphony, Siemens, Germany), which provides real-time guidance and control. Contrast-enhanced MR imaging was performed to evaluate the efficacy of thermal ablation immediately and 3 months after HIFU treatment. The treatment time and adverse events were recorded. Results: The mean fibroid volume was 97.0 ± 78.3 (range, 12.7-318.3) cm 3 . According to the treatment plan, an average 75.0 ± 11.4% (range, 37.8-92.4%) of the fibroid volume was treated. The mean fibroid volume immediately after HIFU was 109.7 ± 93.1 (range, 11.9-389.6) cm 3 , slightly enlarged because of edema. The average non-perfused volume was 83.3 ± 71.7 (range, 7.7-282.9) cm 3 , the average fractional ablation, which was defined as non-perfused volume divided by the fibroid volume immediately after HIFU treatment, was 76.9 ± 18.7% (range, 21.0-97.0%). There were no statistically significant differences between the treatment volume and the non-perfused volume. Follow-up magnetic resonance imaging (MRI) at 3 months obtained in 12 patients, the fibroid volume decreased by 31.4 ± 29.3% (range, -1.9 to 60.0%) in average, with paired t

  1. Feasibility of magnetic resonance imaging-guided high intensity focused ultrasound therapy for ablating uterine fibroids in patients with bowel lies anterior to uterus

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Lian; Chen Wenzhi [Clinical Center for Tumour Therapy of 2nd Affiliated Hospital of Chongqing University of Medical Sciences, Chongqing 400010 (China); Liu Yinjiang; Hu Xiao [National Engineering Research Center of Ultrasound Medicine, Chongqing 400010 (China); Zhou Kun [Clinical Center for Tumour Therapy of 2nd Affiliated Hospital of Chongqing University of Medical Sciences, Chongqing 400010 (China); Chen Li [National Engineering Research Center of Ultrasound Medicine, Chongqing 400010 (China); Peng Song; Zhu Hui [Clinical Center for Tumour Therapy of 2nd Affiliated Hospital of Chongqing University of Medical Sciences, Chongqing 400010 (China); Zou Huiling [National Engineering Research Center of Ultrasound Medicine, Chongqing 400010 (China); Bai Jin [Institute of Ultrasound Engineering in Medicine of Chongqing University of Medical Sciences, Chongqing 400016 (China); Wang Zhibiao [Clinical Center for Tumour Therapy of 2nd Affiliated Hospital of Chongqing University of Medical Sciences, Chongqing 400010 (China); National Engineering Research Center of Ultrasound Medicine, Chongqing 400010 (China); Institute of Ultrasound Engineering in Medicine of Chongqing University of Medical Sciences, Chongqing 400016 (China)], E-mail: wangzhibiao@haifu.com.cn

    2010-02-15

    Purpose: To prospectively evaluate the feasibility of magnetic resonance (MR) imaging-guided high intensity focused ultrasound (HIFU) therapeutic ablation of uterine fibroids in patients with bowel lies anterior to uterus. Materials and methods: Twenty-one patients with 23 uterine fibroids underwent MR imaging-guided high intensity focused ultrasound treatment, with a mean age of 39.4 {+-} 6.9 (20-49) years, with fibroids average measuring 6.0 {+-} 1.6 (range, 2.9-9.5) cm in diameter. After being compressed with a degassed water balloon on abdominal wall, MR imaging-guided high intensity focused ultrasound treatment was performed under conscious sedation by using fentanyl and midazolam. This procedure was performed by a Haifu JM focused ultrasound tumour therapeutic system (JM2.5C, Chongqing Haifu Technology Co., Ltd., China), in combination with a 1.5-Tesla MRI system (Symphony, Siemens, Germany), which provides real-time guidance and control. Contrast-enhanced MR imaging was performed to evaluate the efficacy of thermal ablation immediately and 3 months after HIFU treatment. The treatment time and adverse events were recorded. Results: The mean fibroid volume was 97.0 {+-} 78.3 (range, 12.7-318.3) cm{sup 3}. According to the treatment plan, an average 75.0 {+-} 11.4% (range, 37.8-92.4%) of the fibroid volume was treated. The mean fibroid volume immediately after HIFU was 109.7 {+-} 93.1 (range, 11.9-389.6) cm{sup 3}, slightly enlarged because of edema. The average non-perfused volume was 83.3 {+-} 71.7 (range, 7.7-282.9) cm{sup 3}, the average fractional ablation, which was defined as non-perfused volume divided by the fibroid volume immediately after HIFU treatment, was 76.9 {+-} 18.7% (range, 21.0-97.0%). There were no statistically significant differences between the treatment volume and the non-perfused volume. Follow-up magnetic resonance imaging (MRI) at 3 months obtained in 12 patients, the fibroid volume decreased by 31.4 {+-} 29.3% (range, -1.9 to 60

  2. Multimodality Image Fusion with PSMA PET/CT and High-Intensity Focused Ultrasound Focal Therapy for Primary Diagnosis and Management of Prostate Cancer: A Planned Research Initiative

    Directory of Open Access Journals (Sweden)

    Marcia C. Javitt

    2017-10-01

    Full Text Available Recent developments in diagnostic imaging herald a new approach to diagnosis and management of prostate cancer. Multimodality fusion that combines anatomic with functional imaging data has surpassed either of the two alone. This opens up the possibility to “find and fix” malignancy with greater accuracy than ever before. This is particularly important for prostate cancer because it is the most common male cancer in most developed countries. This article describes technical advances under investigation at our institution and others using multimodality image fusion of magnetic resonance imaging (MRI, transrectal ultrasound (TRUS, and PSMA PET/CT (defined as the combination of prostate-specific membrane antigen [PSMA], positron emission tomography [PET], and computed tomography [CT] for personalized medicine in the diagnosis and focal therapy of prostate cancer with high-intensity focused ultrasound (HiFUS.

  3. High-Intensity Focused Ultrasound (HIFU) Using Sonablate® Devices for the Treatment of Benign Prostatic Hyperplasia and Localized Prostate Cancer: 18-year experience

    Science.gov (United States)

    Uchida, Toyoaki

    2011-09-01

    From 1993 to 2010, we have treated 156 patients benign prostatic hyperplasia (BPH) and 1,052 patients localized prostate cancer high-intensity focused ultrasound (HIFU). Four different HIFU devices, SonablateR-200, SonablateR-500, SonablateR-500 version 4 and Sonablate® TCM, have been used for this study. Clinical outcome of HIFU for BPH did not show any superior effects to transurethral resection of the prostate, laser surgery or transurethral vapolization of the prostate. However, HIFU appears to be a safe and minimally invasive therapy for patients with localized prostate cancer, especially low- and intermediate-risk patients. The rate of clinical outcome has significantly improved over the years due to technical improvements in the device.

  4. Development and internal validation of prediction models for biochemical failure and composite failure after focal salvage high intensity focused ultrasound for local radiorecurrent prostate cancer : Presentation of risk scores for individual patient prognoses

    NARCIS (Netherlands)

    Peters, Max; Kanthabalan, Abi; Shah, Taimur T; McCartan, Neil; Moore, Caroline M.; Arya, Manit; van der Voort van Zyp, Jochem R.; Moerland, Marinus A.; Hindley, Richard G.; Emberton, Mark; Ahmed, Hashim U

    2018-01-01

    Purpose Patient selection for focal salvage remains difficult. Therefore, we developed and internally validated prediction models for biochemical failure (BF) and a composite endpoint (CE) following focal salvage high intensity focused ultrasound (HIFU) for radiorecurrent prostate cancer. Materials

  5. In-line silica capillary tube all-silica fiber-optic Fabry-Perot interferometric sensor for detecting high intensity focused ultrasound fields.

    Science.gov (United States)

    Wang, D H; Wang, S J; Jia, P G

    2012-06-01

    Aiming at detecting high intensity focused ultrasound (HIFU) fields, this letter reports on a novel in-line silica capillary tube all-silica fiber-optic Fabry-Perot (ILSCT-ASFP) interferometric sensor fabricated by splicing a commercially available silica capillary tube to two single-mode fibers. The experimental results show that such a novel ILSCT-ASFP interferometric sensor with a cavity length of ∼60.76 μm has an excellent fringe visibility of up to ∼20 dB, and the fringe visibility is still good when the cavity length extends up to ∼1031.07 μm. The measured wavelength-temperature sensitivity of 0.000858 nm/°C shows that the wavelength drift of the fabricated ILSCT-ASFP interferometric sensor towards temperature is extremely low. Meanwhile, the measurement of HIFU fields by this novel sensor is demonstrated, and the experimental results indicate that the signal-to-noise ratio of the sensing system for sensing a 0.93 MHz HIFU field with a pressure of 2.69 MPa in the focus area can reach 42.8 dB. The corresponding noise equivalent pressure is 0.0194 MPa, and the calculated acoustic sensitivity is 65.4 mV/MPa over a 2.5 MHz measurement bandwidth.

  6. Jet formation and shock wave emission during collapse of ultrasound-induced cavitation bubbles and their role in the therapeutic applications of high-intensity focused ultrasound

    International Nuclear Information System (INIS)

    Brujan, E A; Ikeda, T; Matsumoto, Y

    2005-01-01

    The dynamics of inertial cavitation bubbles produced by short pulses of high-intensity focused ultrasound near a rigid boundary are studied to get a better understanding of the role of jet formation and shock wave emission during bubble collapse in the therapeutic applications of ultrasound. The bubble dynamics are investigated by high-speed photography with up to 2 million frames/s and acoustic measurements, as well as by numerical calculations. The significant parameter of this study is the dimensionless stand-off, γ, which is defined as the distance of the bubble centre at its maximum expansion scaled by the maximum bubble radius. High-speed photography is applied to observe the bubble motion and the velocity of the liquid jet formed during bubble collapse. Hydrophone measurements are used to determine the pressure and the duration of the shock wave emitted during bubble rebound. Calculations yield the variation with time of the bubble wall, the maximum velocity and the kinetic energy of the re-entrant jet. The comparisons between experimental and numerical data are favourable with regard to both shape history and translational motion of the bubble. The acoustic energy constitutes the largest individual amount in the energy balance of bubble collapse. The ratio of the shock wave energy, measured at 10 mm from the emission centre, to the cavitation bubble energy was 1:2.4 at γ = 1.55 and 1:3.5 at γ = 1. At this distance, the shock wave pressure ranges from 0.122 MPa, at γ = 1, to 0.162 MPa, at γ 1.55, and the temporal duration at the half maximum level is 87 ns. The maximum jet velocity ranges from 27 m s -1 , at γ = 1, to 36 m s -1 , at γ = 1.55. For γ < 1.2, the re-entrant jet can generate an impact pressure on the nearby boundary larger than 50 MPa. We discuss the implications of the results for the therapeutic applications of high-intensity focused ultrasound

  7. Basic study on ultrasonic monitoring using 1.5-dimensional ultrasound phased array for ultrasound-guided high-intensity focused ultrasound treatment

    Science.gov (United States)

    Takagi, Ryo; Iwasaki, Ryosuke; Tomiyasu, Kentaro; Yoshizawa, Shin; Umemura, Shin-ichiro

    2017-07-01

    We have been studying a real-time detection method for tissue changes induced by high-intensity focused ultrasound (HIFU) treatment using ultrasonic RF signals. It has been difficult to track the target region when the tissue to be treated deviates from the imaging plane along the elevation axis of the probe. In this study, a new 1.5-dimensional (1.5D) prototype phased array probe consisting of transducer elements along both the lateral and elevation axes was developed to track tissue motion along the elevation axis of the probe, and the elevational displacement range where the tracking is effective was investigated. The complex cross-correlation coefficient based on a block matching algorithm was applied to 2.5D volumetric RF images acquired by the 1.5D probe and the displacement vector along the elevation axis was calculated. From the results, it was found that the effective tracking range using this prototype probe was up to 3 mm, about 3 times that of a conventional 1D imaging probe. The proposed 1.5D phased array probe has the potential to track target tissue with intrafractional motion.

  8. Robotized High Intensity Focused Ultrasound (HIFU) system for treatment of mobile organs using motion tracking by ultrasound imaging: An in vitro study.

    Science.gov (United States)

    Chanel, Laure-Anais; Nageotte, Florent; Vappou, Jonathan; Luo, Jianwen; Cuvillon, Loic; de Mathelin, Michel

    2015-01-01

    High Intensity Focused Ultrasound (HIFU) therapy is a very promising method for ablation of solid tumors. However, intra-abdominal organ motion, principally due to breathing, is a substantial limitation that results in incorrect tumor targeting. The objective of this work is to develop an all-in-one robotized HIFU system that can compensate motion in real-time during HIFU treatment. To this end, an ultrasound visual servoing scheme working at 20 Hz was designed. It relies on the motion estimation by using a fast ultrasonic speckle tracking algorithm and on the use of an interleaved imaging/HIFU sonication sequence for avoiding ultrasonic wave interferences. The robotized HIFU system was tested on a sample of chicken breast undergoing a vertical sinusoidal motion at 0.25 Hz. Sonications with and without motion compensation were performed in order to assess the effect of motion compensation on thermal lesions induced by HIFU. Motion was reduced by more than 80% thanks to this ultrasonic visual servoing system.

  9. MR thermometry analysis program for laser- or high-intensity focused ultrasound (HIFU)-induced heating at a clinical MR scanner

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Ju; Jeong, Ki Young; Oh, Seung Jae; Park, Eun Hae; Lee, Young Han; Suh, Jin Suck [Yonsei University College of Medicine, Seoul (Korea, Republic of); Kim, Dae Hong [National Cancer Center, Goyang (Korea, Republic of)

    2014-12-15

    Magnetic resonance (MR) thermometry is a noninvasive method for monitoring local temperature change during thermal therapy. In this study, a MR temperature analysis program was established for a laser with gold nanorods (GNRs) and high-intensity focused ultrasound (HIFU)-induced heating MR thermometry. The MR temperature map was reconstructed using the water proton resonance frequency (PRF) method. The temperature-sensitive phase difference was acquired by using complex number subtraction instead of direct phase subtraction in order to avoid another phase unwrapping process. A temperature map-analyzing program was developed and implemented in IDL (Interactive Data Language) for effective temperature monitoring. This one program was applied to two different heating devices at a clinical MR scanner. All images were acquired with the fast spoiled gradient echo (fSPGR) pulse sequence on a 3.0 T GE Discovery MR750 scanner with an 8-channel knee array coil or with a home-built small surface coil. The analyzed temperature values were confirmed by using values simultaneously measured with an optical temperature probe (R{sup 2} = 0.996). The temperature change in small samples induced by a laser or by HIFU was analyzed by using a raw data, that consisted of complex numbers. This study shows that our MR thermometry analysis program can be used for thermal therapy study with a laser or HIFU at a clinical MR scanner. It can also be applied to temperature monitoring for any other thermal therapy based on the PRF method.

  10. Enhancing effects of SonoVue, a microbubble sonographic contrast agent, on high-intensity focused ultrasound ablation in rabbit livers in vivo.

    Science.gov (United States)

    Luo, Wen; Zhou, Xiaodong; Ren, Xiaolong; Zheng, Minjuan; Zhang, Jun; He, Guangbin

    2007-04-01

    The purpose of this study was to explore the enhancing biological effects of SonoVue (Bracco SpA, Milan, Italy), a sulfur hexafluoride sonographic contrast agent, on high-intensity focused ultrasound (HIFU) ablation in vivo. Forty-five rabbits were randomly divided into 3 groups and underwent laparotomy. Animals in group 1 were given injections of 0.2 mL of SonoVue intravenously; animals in group 2 were given physiologic saline; and those in group 3 were not given injections as control. The exposure time was set at 2 seconds with the acoustic power at 600 W. After HIFU ablations, volumes of coagulated regions were measured. Liver tissues were examined under light microscopy with hematoxylin-eosin staining and under transmission electron microscopy. Coagulated volumes in group 1 (mean +/- SD, 2.41 +/- 0.44 cm(3)) were larger than those in group 2 (0.80 +/- 0.13 cm(3)) and group 3 (0.83 +/- 0.16 cm(3)) (P SonoVue can substantially enhance the ablation effects of HIFU, suggesting that microbubble contrast agents may be useful for improving HIFU efficiency.

  11. Can pre- and postoperative magnetic resonance imaging predict recurrence-free survival after whole-gland high-intensity focused ablation for prostate cancer?

    Energy Technology Data Exchange (ETDEWEB)

    Rosset, Remy; Bratan, Flavie [Hopital Edouard Herriot, Hospices Civils de Lyon, Department of Urinary and Vascular Radiology, Lyon (France); Crouzet, Sebastien [Hopital Edouard Herriot, Hospices Civils de Lyon, Department of Urology, Lyon (France); Universite de Lyon, Lyon (France); Faculte de Medecine Lyon Est, Universite Lyon 1, Lyon (France); Inserm, U1032, LabTau, Lyon (France); Tonoli-Catez, Helene [Hopital Edouard Herriot, Hospices Civils de Lyon, Department of Urology, Lyon (France); Mege-Lechevallier, Florence [Hopital Edouard Herriot, Hospices Civils de Lyon, Department of Pathology, Lyon (France); Gelet, Albert [Hopital Edouard Herriot, Hospices Civils de Lyon, Department of Urology, Lyon (France); Inserm, U1032, LabTau, Lyon (France); Rouviere, Olivier [Hopital Edouard Herriot, Hospices Civils de Lyon, Department of Urinary and Vascular Radiology, Lyon (France); Universite de Lyon, Lyon (France); Faculte de Medecine Lyon Est, Universite Lyon 1, Lyon (France); Inserm, U1032, LabTau, Lyon (France)

    2017-04-15

    Our aim was to assess whether magnetic resonance imaging (MRI) features predict recurrence-free survival (RFS) after prostate cancer high-intensity focused ultrasound (HIFU) ablation. We retrospectively selected 81 patients who underwent (i) whole-gland HIFU ablation between 2007 and 2011 as first-line therapy or salvage treatment after radiotherapy or brachytherapy, and (ii) pre- and postoperative MRI. On preoperative imaging, two senior (R1, R2) and one junior (R3) readers assessed the number of sectors invaded by the lesion with the highest Likert score (dominant lesion) using a 27-sector diagram. On postoperative imaging, readers assessed destruction of the dominant lesion using a three-level score. Multivariate analysis included the number of sectors invaded by the dominant lesion, its Likert and destruction scores, the pre-HIFU prostate-specific antigen (PSA) level, Gleason score, and the clinical setting (primary/salvage). The most significant predictor was the number of prostate sectors invaded by the dominant lesion for R2 and R3 (p≤0.001) and the destruction score of the dominant lesion for R1 (p = 0.011). The pre-HIFU PSA level was an independent predictor for R2 (p = 0.014), but with only marginal significance for R1 (p = 0.059) and R3 (p = 0.053). The dominant lesion's size and destruction assessed by MRI provide independent prognostic information compared with usual predictors. (orig.)

  12. MRI-guided high-intensity focused ultrasound ablation of bone: evaluation of acute findings with MR and CT imaging in a swine model.

    Science.gov (United States)

    Bucknor, Matthew D; Rieke, Viola; Do, Loi; Majumdar, Sharmila; Link, Thomas M; Saeed, Maythem

    2014-11-01

    To evaluate hyperacute (guided high-intensity focused ultrasound (MRgHIFU) in a swine bone model as a function of sonication number and energy. Experimental procedures received approval from the local Institutional Animal Care and Use Committee. MRgHIFU was used to create distal and proximal ablations in the right femur of eight pigs. Each target was dosed with four or six sonications within similar volumes. The energy dosed to the distal target was higher (419 ± 19 J) than the proximal target (324 ± 17 J). The targeted femur and contralateral control were imaged before and after ablation using MR at 3T. Qualitative changes in signal on T1-weighted, T2-weighted, and T1-weighted postcontrast images were assessed. Ablation dimensions were calculated from postcontrast MRI. The 64-slice CT images were also obtained before and after ablation and qualitative changes were assessed. MRgHIFU bone ablation size measured on average 8.5 × 21.1 × 16.2 mm (transverse × craniocaudal × anteroposterior). Interestingly, within similar prescribed volumes, increasing the number of sonications from 4 to 6 increased the depth of the intramedullary hypoenhanced zone from 2.9 mm to 6.5 mm (P bone. Unlike CT, T2-weighted and contrast-enhanced MR demonstrated the hyperacute structural changes in the femur and surrounding soft tissue. © 2013 Wiley Periodicals, Inc.

  13. A comparison of ultrasound-guided high intensity focused ultrasound for the treatment of uterine fibroids in patients with an anteverted uterus and a retroverted uterus.

    Science.gov (United States)

    Zhang, Wenyi; He, Min; Huang, Guohua; He, Jia

    2016-09-01

    The aim of this study was to compare the treatment outcomes of ultrasound-guided high-intensity focused ultrasound (USgHIFU) for uterine fibroids in patients with an anteverted uterus versus a retroverted uterus. Based on the principles of statistics we enrolled 221patients with an anteverted uterus and 221 with a retroverted uterus. All patients had a solitary uterine fibroid and every fibroid was identified as hypointense on the T2 weighted images (T2WI) on magnetic resonance. The baseline characteristics of the patients, treatment results and adverse events were compared between the two groups. There were no significant differences in baseline characteristics between the two groups. The average non-perfused volume ratio of fibroids was 85.2 ± 18.7% in the group of patients with a retroverted uterus, while it was 87.7 ± 11.8% in patients with an anteverted uterus (P uterus were treated using lower sonication power and longer sonication time. During the procedure patients with a retroverted uterus had a higher incidence of sciatic/buttock pain and groin pain, while patients with an anteverted uterus complained of lower abdominal pain or a burning sensation on the skin. Immediately after USgHIFU, the rates of sciatic/buttock pain and skin burn were significantly higher in patients with a retroverted uterus. The results of this study indicated that uterine fibroids with hypointensity on T2WI in a retroverted uterus can be safely and effectively treated with USgHIFU. However, the fibroids in an anteverted uterus are easier to treat with USgHIFU.

  14. Superparamagnetic PLGA-iron oxide microcapsules for dual-modality US/MR imaging and high intensity focused US breast cancer ablation.

    Science.gov (United States)

    Sun, Yang; Zheng, Yuanyi; Ran, Haitao; Zhou, Yang; Shen, Hongxia; Chen, Yu; Chen, Hangrong; Krupka, Tianyi M; Li, Ao; Li, Pan; Wang, Zhibiao; Wang, Zhigang

    2012-08-01

    Organic/inorganic, hybrid, multifunctional, material-based platforms combine the merits of diverse functionalities of inorganic nanoparticles and the excellent biocompatibility of organic systems. In this work, superparamagnetic poly(lactic-co-glycolic acid) (PLGA) microcapsules (Fe(3)O(4)/PLGA) have been developed, as a proof-of-concept, for the application in ultrasound/magnetic resonance dual-modality biological imaging and enhancing the therapeutic efficiency of high intensity focused ultrasound (HIFU) breast cancer surgery in vitro and in vivo. Hydrophobic Fe(3)O(4) nanoparticles were successfully integrated into PLGA microcapsules by a typical double emulsion evaporation process. In this process, highly dispersed superparamagnetic Fe(3)O(4)/PLGA composite microcapsules with well-defined spherical morphology were obtained with an average diameter of 885.6 nm. The potential of these microcapsules as dual contrast agents for ultrasonography and magnetic resonance imaging were demonstrated in vitro and, also, preliminarily in vivo. Meanwhile, the prepared superparamagnetic composite microcapsules were administrated into rabbits bearing breast cancer model for the evaluation of the in vivo HIFU synergistic ablation efficiency caused by the introduction of such microcapsules. Our results showed that the employment of the composite microcapsules could efficiently enhance ultrasound imaging of cancer, and greatly enhance the HIFU ablation of breast cancer in rabbits. In addition, pathological examination was systematically performed to detect the structural changes of the target tissue caused by HIFU ablation. This finding demonstrated that successful introduction of these superparamagnetic microcapsules into HIFU cancer surgery provided an alternative strategy for the highly efficient imaging-guided non-invasive HIFU synergistic therapy of cancer. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Evaluation of superparamagnetic iron oxide-polymer composite microcapsules for magnetic resonance-guided high-intensity focused ultrasound cancer surgery.

    Science.gov (United States)

    Sun, Yang; Zheng, Yuanyi; Li, Pan; Wang, Dong; Niu, Chengcheng; Gong, Yuping; Huang, Rongzhong; Wang, Zhibiao; Wang, Zhigang; Ran, Haitao

    2014-11-03

    Superparamagnetic poly (lactic-co-glycolic acid) (PLGA)-coated Fe3O4 microcapsules are receiving increased attention as potential diagnostic and therapeutic modalities in the field of oncology. In this study, PLGA-coated Fe3O4 microcapsules were combined with a magnetic resonance imaging-guided high-intensity focused ultrasound (MR-guided HIFU) platform, with the objective of investigating the effects of these composite microcapsules regarding MR-guided HIFU liver cancer surgery in vivo. PLGA-coated Fe3O4 microcapsules consisting of a liquid core and a PLGA-Fe3O4 shell were fabricated using a modified double emulsion evaporation method. Their acute biosafety was confirmed in vitro using MDA cells and in vivo using rabbits. To perform MR-guided HIFU surgery, the microcapsules were intravenously injected into a rabbit liver tumor model before MR-guided HIFU. T2-weighted images and MR signal intensity in normal liver parenchyma and tumor tissue were acquired before and after injection, to assess the MR imaging ability of the microcapsules. After MR-guided HIFU ablation tissue temperature mapping, the coagulative volume and histopathology of the tumor tissue were analyzed to investigate the ablation effects of MR-guided HIFUs. Scanning and transmission electron microscopy showed that the microcapsules displayed a spherical morphology and a shell-core structure (mean diameter, 587 nm). The hysteresis curve displayed the typical superparamagnetic properties of the microcapsules, which are critical to their application in MR-guided HIFU surgery. In MR-guided HIFU surgery, these microcapsules functioned as an MRI contrast agent, induced significant hyperthermal enhancement (P microcapsules is a potentially synergistic technique regarding the enhancement of MR-guided HIFU cancer surgery.

  16. Evaluation of the therapeutic efficacy of high-intensity focused ultrasound ablation of hepatocellular carcinoma by three-dimensional sonography with a perflubutane-based contrast agent

    International Nuclear Information System (INIS)

    Numata, Kazushi; Fukuda, Hiroyuki; Ohto, Masao; Itou, Ryu; Nozaki, Akito; Kondou, Masaaki; Morimoto, Manabu; Karasawa, Eii; Tanaka, Katsuaki

    2010-01-01

    Objective: We performed contrast-enhanced three-dimensional sonography (CE 3D US) with a perflubutane-based contrast agent to immediately evaluate the completeness of ablation of small hepatocellular carcinoma (HCC) lesions by extracorporeal high-intensity focused ultrasound (HIFU). Subjects and methods: Twenty-one HCC lesions were treated by a single ultrasound-guided HIFU ablation session, and CE 3D US was performed before, immediately after, and 1 week, and 1 month after HIFU, and contrast-enhanced CT (CE CT) or contrast-enhanced MRI (CE MRI) was performed before HIFU, 1 week and 1 month after HIFU, and during the follow-up period. Results: Immediately and 1 month after HIFU, 17 lesions were evaluated as adequately ablated by CE 3D US, and the other 4 lesions as residual tumors. One month after HIFU, 18 were evaluated as adequately ablated by CE CT or CE MRI, and the other 3 as residual tumors. The evaluation by CE 3D US immediately after HIFU and by CE CT or CE MRI 1 month after HIFU was concordant with 20 lesions. The kappa value for agreement between the findings of CE 3D US and other modalities by two blinded observers was 0.83. When the 1-month CE CT or CE MRI findings were used as the reference standard, the sensitivity, specificity, and accuracy of CE 3D US immediately after HIFU for the diagnosis of the adequate ablation were 100%, 75%, and 95%, respectively. Conclusion: CE 3D US appears to be a useful method for immediate evaluation of therapeutic efficacy of HIFU ablation of HCC lesions.

  17. High intensity focused ultrasound treatment of adenomyosis: The relationship between the features of magnetic resonance imaging on T2 weighted images and the therapeutic efficacy

    International Nuclear Information System (INIS)

    Gong, Chunmei; Setzen, Raymond; Liu, Zhongqiong; Liu, Yunchang; Xie, Bin; Aili, Aixingzi; Zhang, Lian

    2017-01-01

    Objectives: To investigate the relationship between the features of magnetic resonance imaging (MRI) on T2 weighted images (T2WI) and the therapeutic efficacy of high intensity focused ultrasound (HIFU) on adenomyosis. Materials and methods: From January 2011 to November 2015, four hundred and twenty-eight patients with symptomatic adenomyosis were treated with HIFU. Based on the signal intensity and the number of hyperintense foci in the adenomyotic lesions on T2WI, the patients were classified into groups. The day after HIFU ablation patients underwent contrast-enhanced MRI and a comparison was made of non-perfused volume (NPV) ratio, energy efficiency factor (EEF), treatment time, sonication time, and adverse effects. Results: No significant difference in terms of HIFU treatment settings and results was observed between the group of patients with hypointense adenomyotic lesions and the group with isointense adenomyotic lesions (P > 0.05). However, the sonication time and EEF were significantly higher in the group with multiple hyperintense foci compared to the group with few hyperintense foci. The NPV ratio achieved in the lesions with multiple hyperintenese foci was significantly lower than that in the lesions with few hyperintense foci (P < 0.05). No significant difference was observed in the rate of adverse effects between the two groups. Conclusions: Based on our results, the response of the adenomyotic lesions to HIFU treatment is not related to the signal intensity of adenomyotic lesions on T2WI. However, the number of the high signal intensity foci in the adenomyotic lesions on T2WI can be considered as a predictive factor to help select patients for HIFU treatment.

  18. The potential of high intensity focused ultrasound (HIFU) combine phase-sensitive optical coherence tomography (PhS-OCT) for diseases diagnosis, treatment and monitoring

    Science.gov (United States)

    Zhou, Kanheng; Wang, Yan; Feng, Kairui; Li, Chunhui; Huang, Zhihong

    2018-02-01

    HIFU is a truly noninvasive, acoustic therapeutic technique that utilizes high intensity acoustic field in the focus to kill the targeted tissue for disease treatment purpose. The mechanical properties of targeted tissue changes before and after treatment, and this change can be accurately detected by shear wave elastography. Hence, shear wave elastography is usually used for monitoring HIFU treatment asynchronously. To improve the low spatial resolution in ultrasound shear wave elastography, and to perform diseases diagnosis, treatment and monitoring in the same system, a new setup that combines HIFU and PhS-OCT system was proposed in this study. This proposed setup could do 1) HIFU treatment when the transducer works at high energy level, 2) ultrasound induced shear wave optical coherence elastography for HIFU treatment asynchronous monitoring when the transducer works at low energy level. Ex-vivo bovine liver tissue was treated at the same energy level for different time (0s, 1s, 5s, 9s) in this research. Elastography was performed on the lesion area of the sample after HIFU treatment, and the elastogram was reconstructed by the time of flight time method. The elastogram results clearly show the boundary of HIFU lesion area and surrounding normal tissue, even for 1s treatment time. And the average elasticity of the lesion grows linearly as the treatment time increases. Combined with OCT needle probe, the proposed method has a large potential not only to be used for superficial diseases treatment, but also to be used for high-precision-demanded diseases treatment, e.g. nervous disease treatment.

  19. Clinical utility of a microbubble-enhancing contrast (“SonoVue”) in treatment of uterine fibroids with high intensity focused ultrasound: A retrospective study

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Song [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Key Laboratory of Ultrasound in Medicine and Engineering, Department of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Non-invasive and Minimally Invasive Therapeutic Research Center for Uterine Benign Diseases of Chongqing, Chongqing 401121 (China); Xiong, Yu [Department of Obstetrics of Chongqing Haifu Hospital, Chongqing 401121 (China); Non-invasive and Minimally Invasive Therapeutic Research Center for Uterine Benign Diseases of Chongqing, Chongqing 401121 (China); Li, Kequan [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Key Laboratory of Ultrasound in Medicine and Engineering, Department of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Non-invasive and Minimally Invasive Therapeutic Research Center for Uterine Benign Diseases of Chongqing, Chongqing 401121 (China); He, Min [Department of Obstetrics of Chongqing Haifu Hospital, Chongqing 401121 (China); Department of Obstetrics and Gynecology, Suining Central Hospital, Sichuan 629000 (China); Deng, Yongbin; Chen, Li; Zou, Min [Department of Obstetrics of Chongqing Haifu Hospital, Chongqing 401121 (China); Chen, Wenzhi; Wang, Zhibiao [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Key Laboratory of Ultrasound in Medicine and Engineering, Department of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Non-invasive and Minimally Invasive Therapeutic Research Center for Uterine Benign Diseases of Chongqing, Chongqing 401121 (China); He, Jia, E-mail: hejia0820@sina.com.cn [Department of Obstetrics and Gynecology, Suining Central Hospital, Sichuan 629000 (China); and others

    2012-12-15

    Purpose: To evaluate the clinical value of the contrast agent SonoVue in the treatment of uterine fibroids with ultrasound-guided high intensity focused ultrasound (HIFU) therapeutic ablation. Materials and Methods: A total of 291 patients with solitary uterine fibroid from three centers were treated with ultrasound-guided HIFU. Among them, 129 patients from Suining Central Hospital of Sichuan were treated without using SonoVue. 162 patients from the First Hospital of Chongqing Medical University and Chongqing Haifu Hospital were treated with using SonoVue before, during and after HIFU procedure to assess the extent of HIFU. Results: The non-perfused volume (indicative of successful ablation) was observed in all treated uterine fibroids immediately after HIFU ablation; median fractional ablation, defined as non-perfused volume divided by the fibroid volume immediately after HIFU treatment, was 86.0% (range, 28.8–100.0%) in the group with using SonoVue, and 83.0% (8.7–100.0%) without SonoVue. The rate of massive gray scale changes was higher with SonoVue than without the agent. The sonication time to achieve massive gray scale changes was shorter with SonoVue than without. The sonication time for ablating 1 cm{sup 3} of fibroid volume was significantly shorter with using SonoVue than without. No major complications were observed in any patients. Conclusions: Based on our results, SonoVue may enhance the outcome of HIFU ablation and can be used to assess the extent of treatment.

  20. Clinical utility of a microbubble-enhancing contrast ("SonoVue") in treatment of uterine fibroids with high intensity focused ultrasound: a retrospective study.

    Science.gov (United States)

    Peng, Song; Xiong, Yu; Li, Kequan; He, Min; Deng, Yongbin; Chen, Li; Zou, Min; Chen, Wenzhi; Wang, Zhibiao; He, Jia; Zhang, Lian

    2012-12-01

    To evaluate the clinical value of the contrast agent SonoVue in the treatment of uterine fibroids with ultrasound-guided high intensity focused ultrasound (HIFU) therapeutic ablation. A total of 291 patients with solitary uterine fibroid from three centers were treated with ultrasound-guided HIFU. Among them, 129 patients from Suining Central Hospital of Sichuan were treated without using SonoVue. 162 patients from the First Hospital of Chongqing Medical University and Chongqing Haifu Hospital were treated with using SonoVue before, during and after HIFU procedure to assess the extent of HIFU. The non-perfused volume (indicative of successful ablation) was observed in all treated uterine fibroids immediately after HIFU ablation; median fractional ablation, defined as non-perfused volume divided by the fibroid volume immediately after HIFU treatment, was 86.0% (range, 28.8-100.0%) in the group with using SonoVue, and 83.0% (8.7-100.0%) without SonoVue. The rate of massive gray scale changes was higher with SonoVue than without the agent. The sonication time to achieve massive gray scale changes was shorter with SonoVue than without. The sonication time for ablating 1cm(3) of fibroid volume was significantly shorter with using SonoVue than without. No major complications were observed in any patients. Based on our results, SonoVue may enhance the outcome of HIFU ablation and can be used to assess the extent of treatment. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  1. Comparison of the synergistic effect of lipid nanobubbles and SonoVue microbubbles for high intensity focused ultrasound thermal ablation of tumors

    Directory of Open Access Journals (Sweden)

    Yuanzhi Yao

    2016-02-01

    Full Text Available Microbubbles (MBs are considered as an important enhancer for high intensity focused ultrasound (HIFU treatment of benign or malignant tumors. Recently, different sizes of gas-filled bubbles have been investigated to improve the therapeutic efficiency of HIFU thermal ablation and reduce side effects associated with ultrasound power and irradiation time. However, nanobubbles (NBs as an ultrasound contrast agent for synergistic therapy of HIFU thermal ablation remain controversial due to their small nano-size in diameter. In this study, phospholipid-shell and gas-core NBs with a narrow size range of 500–600 nm were developed. The synergistic effect of NBs for HIFU thermal ablation was carefully studied both in excised bovine livers and in breast tumor models of rabbits, and made a critical comparison with that of commercial SonoVue microbubbles (SonoVue MBs. In addition, the pathological changes of the targeted area in tumor tissue after HIFU ablation were further investigated. Phosphate buffer saline (PBS was used as the control. Under the same HIFU parameters, the quantitative echo intensity of B-mode ultrasound image and the volume of coagulative necrosis in lipid NBs groups were significantly higher and larger than that in PBS groups, but could not be demonstrated a difference to that in SonoVue MBs groups both ex vivo and in vivo. These results showed that the synergistic effect of lipid NBs for HIFU thermal ablation were similar with that of SonoVue MBs, and further indicate that lipid NBs could potentially become an enhancer for HIFU thermal ablation of tumors.

  2. Comparison of the synergistic effect of lipid nanobubbles and SonoVue microbubbles for high intensity focused ultrasound thermal ablation of tumors.

    Science.gov (United States)

    Yao, Yuanzhi; Yang, Ke; Cao, Yang; Zhou, Xuan; Xu, Jinshun; Liu, Jianxin; Wang, Qi; Wang, Zhigang; Wang, Dong

    2016-01-01

    Microbubbles (MBs) are considered as an important enhancer for high intensity focused ultrasound (HIFU) treatment of benign or malignant tumors. Recently, different sizes of gas-filled bubbles have been investigated to improve the therapeutic efficiency of HIFU thermal ablation and reduce side effects associated with ultrasound power and irradiation time. However, nanobubbles (NBs) as an ultrasound contrast agent for synergistic therapy of HIFU thermal ablation remain controversial due to their small nano-size in diameter. In this study, phospholipid-shell and gas-core NBs with a narrow size range of 500-600 nm were developed. The synergistic effect of NBs for HIFU thermal ablation was carefully studied both in excised bovine livers and in breast tumor models of rabbits, and made a critical comparison with that of commercial SonoVue microbubbles (SonoVue MBs). In addition, the pathological changes of the targeted area in tumor tissue after HIFU ablation were further investigated. Phosphate buffer saline (PBS) was used as the control. Under the same HIFU parameters, the quantitative echo intensity of B-mode ultrasound image and the volume of coagulative necrosis in lipid NBs groups were significantly higher and larger than that in PBS groups, but could not be demonstrated a difference to that in SonoVue MBs groups both ex vivo and in vivo. These results showed that the synergistic effect of lipid NBs for HIFU thermal ablation were similar with that of SonoVue MBs, and further indicate that lipid NBs could potentially become an enhancer for HIFU thermal ablation of tumors.

  3. Numerical Study for Optimizing Parameters of High-Intensity Focused Ultrasound-Induced Thermal Field during Liver Tumor Ablation: HIFU Simulator

    Directory of Open Access Journals (Sweden)

    Somayeh gharloghi

    2017-03-01

    Full Text Available Introduction High intensity focused ultrasound (HIFU is considered a noninvasive and effective technique for tumor ablation. Frequency and acoustic power are the most effective parameters for temperature distribution and the extent of tissue damage. The aim of this study was to optimize the operating transducer parameters such as frequency and input power in order to acquire suitable temperature and thermal dose distribution in the course of a numerical assessment. Materials and Methods To model the sound propagation, the Khokhlov-Zabolotskava-Kuznetsov (KZK nonlinear wave equation was used and simulation was carried out using MATLAB HIFU toolbox. Bioheat equation was applied to calculate the transient temperature in the liver tissue. Frequency ranges of 2, 3, 4, and 5 MHz and power levels of 50 and 100 W were applied using an extracorporeal transducer. Results Using a frequency of 2 MHz, the maximum temperatures reached 53°C and 90°C in the focal point for power levels of 50 W and 100 W, respectively. With the same powers and using a frequency of 3 MHz, the temperature reached to 71°C and 170°C, respectively. In addition, for these power levels at the frequency of 4 MHz, the temperature reached to 72°C and 145°C, respectively. However, at the 5 MHz frequency, the temperature in the focal spot was either 57°C or 79°C. Conclusion Use of frequency of 2 MHz and power of 100 W led to higher thermal dose distribution, and subsequently, reduction of the treatment duration and complications at the same exposure time in ablation of large tumors.

  4. Preservation of the endometrial enhancement after magnetic resonance imaging-guided high-intensity focused ultrasound ablation of submucosal uterine fibroids

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young-sun [Samsung Medical Center, Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Seoul (Korea, Republic of); Uterine Fibroid Integrated Management Center, MINT Intervention Hospital, Department of Radiology, Seoul (Korea, Republic of); Kim, Tae-Joong; Lee, Jeong-Won; Kim, Byoung-Gie [Samsung Medical Center, Sungkyunkwan University School of Medicine, Department of Obstetrics and Gynecology, Seoul (Korea, Republic of); Lim, Hyo Keun [Samsung Medical Center, Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Seoul (Korea, Republic of); SAIHST, Sungkyunkwan University, Department of Health Sciences and Technology, Seoul (Korea, Republic of); Rhim, Hyunchul [Samsung Medical Center, Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Seoul (Korea, Republic of); Jung, Sin-Ho [SAIHST, Sungkyunkwan University, Department of Health Sciences and Technology, Seoul (Korea, Republic of); Samsung Medical Center, Department of Biostatistics and Clinical Epidemiology, Seoul (Korea, Republic of); Ahn, Joong Hyun [Samsung Biomedical Research Institute, Samsung Medical Center, Biostatistics Team, Seoul (Korea, Republic of)

    2017-09-15

    To evaluate the integrity of endometrial enhancement after magnetic resonance imaging-guided high-intensity focused ultrasound (MR-HIFU) ablation of submucosal uterine fibroids based on contrast-enhanced MRI findings, and to identify the risk factors for endometrial impairment. In total, 117 submucosal fibroids (diameter: 5.9 ± 3.0 cm) in 101 women (age: 43.6 ± 4.4 years) treated with MR-HIFU ablation were retrospectively analysed. Endometrial integrity was assessed with contrast-enhanced T1-weighted images at immediate (n = 101), 3-month (n = 62) and 12-month (n = 15) follow-ups. Endometrial impairment was classified into grades 0 (continuous endometrium), 1 (pin-point, full-thickness discontinuity), 2 (between grade 1 and 3), or 3 (full-thickness discontinuity >1 cm). Risk factors were assessed with generalized estimating equation (GEE) analysis. Among 117 fibroids, grades 0, 1, 2 and 3 endometrial impairments were observed at initial examination in 56.4%, 24.8%, 13.7% and 4.3%, respectively. Among 37 fibroid cases of endometrial impairment for which follow-ups were conducted, 30 showed improvements at 3- and/or 12-month follow-up. GEE analysis revealed the degree of endometrial protrusion was significantly associated with severity of endometrial injury (P < 0.0001). After MR-HIFU ablation of submucosal fibroids, endometrial enhancement was preserved intact or minimally impaired in most cases. Impaired endometrium, which is more common after treating endometrially-protruded fibroids, may recover spontaneously. (orig.)

  5. [High-intensity focused ultrasound (HIFU) for tumor pain relief in inoperable pancreatic cancer : Evaluation with the pain sensation scale (SES)].

    Science.gov (United States)

    Marinova, M; Strunk, H M; Rauch, M; Henseler, J; Clarens, T; Brüx, L; Dolscheid-Pommerich, R; Conrad, R; Cuhls, H; Radbruch, L; Schild, H H; Mücke, M

    2017-02-01

    High-intensity focused ultrasound (HIFU) in combination with palliative standard therapy is an innovative and effective treatment option for pain reduction in patients with inoperable pancreatic cancer. Evaluation of the effects of additive ultrasound (US)-guided HIFU treatment in inoperable pancreatic cancer on the sensory and affective pain perception using validated questionnaries. In this study 20 patients with locally advanced inoperable pancreatic cancer and tumor-related pain were treated by US-guided HIFU (6 stage III, 12 stage IV according to UICC and 2 with local recurrence after surgery). Ablation was performed using the JC HIFU system (HAIFU, Chongqing, China) with an ultrasonic device for real-time imaging. Clinical assessment included evaluation of pain severity using validated questionnaires with particular attention to the pain sensation scale (SES) with its affective and sensory component and the numeric rating scale (NRS). The average pain reduction after HIFU was 2.87 points on the NRS scale and 57.3 % compared to the mean baseline score (n = 15, 75 %) in 19 of 20 treated patients. Four patients did not report pain relief, however, the previous opioid medication could be stopped (n = 2) or the analgesic dosage could be reduced (n = 2). No pain reduction was achieved in one patient. Furthermore, after HIFU emotional as well as sensory pain aspects were significantly reduced (before vs. 1 week after HIFU, p pain scales). US-guided HIFU can be used for effective and early pain relief and reduction of emotional and sensory pain sensation in patients with locally advanced pancreatic cancer.

  6. Preservation of the endometrial enhancement after magnetic resonance imaging-guided high-intensity focused ultrasound ablation of submucosal uterine fibroids

    International Nuclear Information System (INIS)

    Kim, Young-sun; Kim, Tae-Joong; Lee, Jeong-Won; Kim, Byoung-Gie; Lim, Hyo Keun; Rhim, Hyunchul; Jung, Sin-Ho; Ahn, Joong Hyun

    2017-01-01

    To evaluate the integrity of endometrial enhancement after magnetic resonance imaging-guided high-intensity focused ultrasound (MR-HIFU) ablation of submucosal uterine fibroids based on contrast-enhanced MRI findings, and to identify the risk factors for endometrial impairment. In total, 117 submucosal fibroids (diameter: 5.9 ± 3.0 cm) in 101 women (age: 43.6 ± 4.4 years) treated with MR-HIFU ablation were retrospectively analysed. Endometrial integrity was assessed with contrast-enhanced T1-weighted images at immediate (n = 101), 3-month (n = 62) and 12-month (n = 15) follow-ups. Endometrial impairment was classified into grades 0 (continuous endometrium), 1 (pin-point, full-thickness discontinuity), 2 (between grade 1 and 3), or 3 (full-thickness discontinuity >1 cm). Risk factors were assessed with generalized estimating equation (GEE) analysis. Among 117 fibroids, grades 0, 1, 2 and 3 endometrial impairments were observed at initial examination in 56.4%, 24.8%, 13.7% and 4.3%, respectively. Among 37 fibroid cases of endometrial impairment for which follow-ups were conducted, 30 showed improvements at 3- and/or 12-month follow-up. GEE analysis revealed the degree of endometrial protrusion was significantly associated with severity of endometrial injury (P < 0.0001). After MR-HIFU ablation of submucosal fibroids, endometrial enhancement was preserved intact or minimally impaired in most cases. Impaired endometrium, which is more common after treating endometrially-protruded fibroids, may recover spontaneously. (orig.)

  7. Clinical utility of a microbubble-enhancing contrast (“SonoVue”) in treatment of uterine fibroids with high intensity focused ultrasound: A retrospective study

    International Nuclear Information System (INIS)

    Peng, Song; Xiong, Yu; Li, Kequan; He, Min; Deng, Yongbin; Chen, Li; Zou, Min; Chen, Wenzhi; Wang, Zhibiao; He, Jia

    2012-01-01

    Purpose: To evaluate the clinical value of the contrast agent SonoVue in the treatment of uterine fibroids with ultrasound-guided high intensity focused ultrasound (HIFU) therapeutic ablation. Materials and Methods: A total of 291 patients with solitary uterine fibroid from three centers were treated with ultrasound-guided HIFU. Among them, 129 patients from Suining Central Hospital of Sichuan were treated without using SonoVue. 162 patients from the First Hospital of Chongqing Medical University and Chongqing Haifu Hospital were treated with using SonoVue before, during and after HIFU procedure to assess the extent of HIFU. Results: The non-perfused volume (indicative of successful ablation) was observed in all treated uterine fibroids immediately after HIFU ablation; median fractional ablation, defined as non-perfused volume divided by the fibroid volume immediately after HIFU treatment, was 86.0% (range, 28.8–100.0%) in the group with using SonoVue, and 83.0% (8.7–100.0%) without SonoVue. The rate of massive gray scale changes was higher with SonoVue than without the agent. The sonication time to achieve massive gray scale changes was shorter with SonoVue than without. The sonication time for ablating 1 cm 3 of fibroid volume was significantly shorter with using SonoVue than without. No major complications were observed in any patients. Conclusions: Based on our results, SonoVue may enhance the outcome of HIFU ablation and can be used to assess the extent of treatment.

  8. Feasibility Study on MR-Guided High-Intensity Focused Ultrasound Ablation of Sciatic Nerve in a Swine Model: Preliminary Results

    Energy Technology Data Exchange (ETDEWEB)

    Kaye, Elena A., E-mail: kayee@mskcc.org [Memorial Sloan Kettering Cancer Center, Department of Medical Physics (United States); Gutta, Narendra Babu, E-mail: gnbabu.aiims@gmail.com [Memorial Sloan Kettering Cancer Center, Department of Radiology (United States); Monette, Sebastien, E-mail: monettes@mskcc.org [The Rockefeller University, Tri-Institutional Laboratory of Comparative Pathology, Memorial Sloan Kettering Cancer Center, Weill Cornell Medical College (United States); Gulati, Amitabh, E-mail: gulatia@mskcc.org; Loh, Jeffrey, E-mail: jeffreyloh@gmail.com [Memorial Sloan Kettering Cancer Center, Department of Anesthesiology-Critical Care (United States); Srimathveeravalli, Govindarajan, E-mail: srimaths@mskcc.org [Memorial Sloan Kettering Cancer Center, Department of Radiology (United States); Ezell, Paula C., E-mail: paula.ezell@intusurg.com [The Rockefeller University, Tri-Institutional Laboratory of Comparative Pathology, Memorial Sloan Kettering Cancer Center, Weill Cornell Medical College (United States); Erinjeri, Joseph P., E-mail: erinjerj@mskcc.org; Solomon, Stephen B., E-mail: solomons@mskcc.org; Maybody, Majid, E-mail: maybodym@mskcc.org [Memorial Sloan Kettering Cancer Center, Department of Radiology (United States)

    2015-08-15

    IntroductionSpastic patients often seek neurolysis, the permanent destruction of the sciatic nerve, for better pain management. MRI-guided high-intensity focused ultrasound (MRgHIFU) may serve as a noninvasive alternative to the prevailing, more intrusive techniques. This in vivo acute study is aimed at performing sciatic nerve neurolysis using a clinical MRgHIFU system.MethodsThe HIFU ablation of sciatic nerves was performed in swine (n = 5) using a HIFU system integrated with a 3 T MRI scanner. Acute lesions were confirmed using T1-weighted contrast-enhanced (CE) MRI and histopathology using hematoxylin and eosin staining. The animals were euthanized immediately following post-ablation imaging.ResultsReddening and mild thickening of the nerve and pallor of the adjacent muscle were seen in all animals. The HIFU-treated sections of the nerves displayed nuclear pyknosis of Schwann cells, vascular hyperemia, perineural edema, hyalinization of the collagenous stroma of the nerve, myelin sheet swelling, and loss of axons. Ablations were visible on CE MRI. Non-perfused volume of the lesions (5.8–64.6 cc) linearly correlated with estimated lethal thermal dose volume (4.7–34.2 cc). Skin burn adjacent to the largest ablated zone was observed in the first animal. Bilateral treatment time ranged from 55 to 138 min, and preparation time required 2 h on average.ConclusionThe acute pilot study in swine demonstrated the feasibility of a noninvasive neurolysis of the sciatic nerve using a clinical MRgHIFU system. Results revealed that acute HIFU nerve lesions were detectable on CE MRI, gross pathology, and histology.

  9. High intensity focused ultrasound (HIFU) applied to hepato-bilio-pancreatic and the digestive system—current state of the art and future perspectives

    Science.gov (United States)

    Diana, Michele; Schiraldi, Luigi; Liu, Yu-Yin; Memeo, Riccardo; Mutter, Didier; Pessaux, Patrick

    2016-01-01

    Background High intensity focused ultrasound (HIFU) is emerging as a valid minimally-invasive image-guided treatment of malignancies. We aimed to review to current state of the art of HIFU therapy applied to the digestive system and discuss some promising avenues of the technology. Methods Pertinent studies were identified through PubMed and Embase search engines using the following keywords, combined in different ways: HIFU, esophagus, stomach, liver, pancreas, gallbladder, colon, rectum, and cancer. Experimental proof of the concept of endoluminal HIFU mucosa/submucosa ablation using a custom-made transducer has been obtained in vivo in the porcine model. Results Forty-four studies reported on the clinical use of HIFU to treat liver lesions, while 19 series were found on HIFU treatment of pancreatic cancers and four studies included patients suffering from both liver and pancreatic cancers, reporting on a total of 1,682 and 823 cases for liver and pancreas, respectively. Only very limited comparative prospective studies have been reported. Conclusions Digestive system clinical applications of HIFU are limited to pancreatic and liver cancer. It is safe and well tolerated. The exact place in the hepatocellular carcinoma (HCC) management algorithm remains to be defined. HIFU seems to add clear survival advantages over trans arterial chemo embolization (TACE) alone and similar results when compared to radio frequency (RF). For pancreatic cancer, HIFU achieves consistent cancer-related pain relief. Further research is warranted to improve targeting accuracy and efficacy monitoring. Furthermore, additional work is required to transfer this technology on appealing treatments such as endoscopic HIFU-based therapies. PMID:27500145

  10. High intensity focused ultrasound treatment of adenomyosis: The relationship between the features of magnetic resonance imaging on T2 weighted images and the therapeutic efficacy

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Chunmei [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Key Laboratory of Ultrasound in Medicine and Engineering, Chongqing Haifu Hospital, College of Biomedical Engineering, Chongqing Medical University, Chongqing (China); Setzen, Raymond [Department of Obstetrics and Gynecology, Chris Hani Baragwanath Academic Hospital, Johannesburg (South Africa); Liu, Zhongqiong; Liu, Yunchang [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Key Laboratory of Ultrasound in Medicine and Engineering, Chongqing Haifu Hospital, College of Biomedical Engineering, Chongqing Medical University, Chongqing (China); Xie, Bin [Department of Ultrasound, Huanggang Central Hospital, Huanggang City, Hubei 438000 (China); Aili, Aixingzi, E-mail: 1819483078@qq.com [Shanghai First Maternity and Infant Health Hospital, Shanghai (China); Zhang, Lian, E-mail: lianwzhang@yahoo.com [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Key Laboratory of Ultrasound in Medicine and Engineering, Chongqing Haifu Hospital, College of Biomedical Engineering, Chongqing Medical University, Chongqing (China)

    2017-04-15

    Objectives: To investigate the relationship between the features of magnetic resonance imaging (MRI) on T2 weighted images (T2WI) and the therapeutic efficacy of high intensity focused ultrasound (HIFU) on adenomyosis. Materials and methods: From January 2011 to November 2015, four hundred and twenty-eight patients with symptomatic adenomyosis were treated with HIFU. Based on the signal intensity and the number of hyperintense foci in the adenomyotic lesions on T2WI, the patients were classified into groups. The day after HIFU ablation patients underwent contrast-enhanced MRI and a comparison was made of non-perfused volume (NPV) ratio, energy efficiency factor (EEF), treatment time, sonication time, and adverse effects. Results: No significant difference in terms of HIFU treatment settings and results was observed between the group of patients with hypointense adenomyotic lesions and the group with isointense adenomyotic lesions (P > 0.05). However, the sonication time and EEF were significantly higher in the group with multiple hyperintense foci compared to the group with few hyperintense foci. The NPV ratio achieved in the lesions with multiple hyperintenese foci was significantly lower than that in the lesions with few hyperintense foci (P < 0.05). No significant difference was observed in the rate of adverse effects between the two groups. Conclusions: Based on our results, the response of the adenomyotic lesions to HIFU treatment is not related to the signal intensity of adenomyotic lesions on T2WI. However, the number of the high signal intensity foci in the adenomyotic lesions on T2WI can be considered as a predictive factor to help select patients for HIFU treatment.

  11. Magnetic resonance imaging for the exploitation of bubble-enhanced heating by high-intensity focused ultrasound: a feasibility study in ex vivo liver.

    Science.gov (United States)

    Elbes, Delphine; Denost, Quentin; Robert, Benjamin; Köhler, Max O; Tanter, Mickaël; Bruno, Quesson

    2014-05-01

    Bubble-enhanced heating (BEH) may be exploited to improve the heating efficiency of high-intensity focused ultrasound in liver and to protect tissues located beyond the focal point. The objectives of this study, performed in ex vivo pig liver, were (i) to develop a method to determine the acoustic power threshold for induction of BEH from displacement images measured by magnetic resonance acoustic radiation force imaging (MR-ARFI), and (ii) to compare temperature distribution with MR thermometry for HIFU protocols with and without BEH. The acoustic threshold for generation of BEH was determined in ex vivo pig liver from MR-ARFI calibration curves of local tissue displacement resulting from sonication at different powers. Temperature distributions (MR thermometry) resulting from "conventional" sonications (20 W, 30 s) were compared with those from "composite" sonications performed at identical parameters, but after a HIFU burst pulse (0.5 s, acoustic power over the threshold for induction of BEH). Displacement images (MR-ARFI) were acquired between sonications to measure potential modifications of local tissue displacement associated with modifications of tissue acoustic characteristics induced by the burst HIFU pulse. The acoustic threshold for induction of BEH corresponded to a displacement amplitude of approximately 50 μm in ex vivo liver. The displacement and temperature images of the composite group exhibited a nearly spherical pattern, shifted approximately 4 mm toward the transducer, in contrast to elliptical shapes centered on the natural focal position for the conventional group. The gains in maximum temperature and displacement values were 1.5 and 2, and the full widths at half-maximum of the displacement data were 1.7 and 2.2 times larger than in the conventional group in directions perpendicular to ultrasound propagation axes. Combination of MR-ARFI and MR thermometry for calibration and exploitation of BEH appears to increase the efficiency and safety

  12. Magnetic Resonance–Guided High-Intensity Focused Ultrasound (MRgHIFU) Treatment of Symptomatic Uterine Fibroids: An Evidence-Based Analysis

    Science.gov (United States)

    Pron, G

    2015-01-01

    Background Magnetic resonance–guided high-intensity focused ultrasound (MRgHIFU) is a noninvasive uterine-preserving treatment alternative to hysterectomy for women with symptomatic uterine leiomyomas (fibroids). Uterine fibroids commonly occur, have a broad impact on women's health and lifestyle, continue to be the main indication for hysterectomy, and represent a costly public health burden. Objectives The objectives of the analysis were to evaluate patients’ eligibility for MRgHIFU treatment of symptomatic uterine fibroids and the technical success, safety, effectiveness, and durability of this treatment. The review also compared the safety and effectiveness of MRgHIFU with other minimally invasive uterine-preserving treatments and surgeries for uterine fibroids. Methods A literature search was performed on March 27, 2014, using Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid EMBASE, EBSCO Cumulative Index to Nursing & Allied Health Literature (CINAHL), and EBM Reviews, for studies published from January 1, 2000, to March 27, 2014. Results The evidence review identified 2 systematic reviews, 2 RCTs, 45 cohort study reports, and 19 case reports involving HIFU treatment of symptomatic uterine fibroids. Eligibility for MRgHIFU treatment was variable, ranging from 14% to 74%. In clinical cohort studies involving 1,594 patients, 26 major complications (1.6%) were reported. MRgHIFU resulted in statistically and clinically significant reductions in fibroid-related symptoms in studies conducted in 10 countries, although few involved follow-up longer than 1 year. Retreatment rates following MRgHIFU were higher in early clinical studies involving regulated restrictions in the extent of fibroid ablation than in later reports involving near-complete ablation. Emergent interventions, however, were rare. Although a desire for fertility was an exclusion criteria for treatment, spontaneous term pregnancies did occur following HIFU. There were no

  13. Magnetic Resonance-Guided High-Intensity Focused Ultrasound (MRgHIFU) Treatment of Symptomatic Uterine Fibroids: An Evidence-Based Analysis.

    Science.gov (United States)

    Pron, G

    2015-01-01

    Magnetic resonance-guided high-intensity focused ultrasound (MRgHIFU) is a noninvasive uterine-preserving treatment alternative to hysterectomy for women with symptomatic uterine leiomyomas (fibroids). Uterine fibroids commonly occur, have a broad impact on women's health and lifestyle, continue to be the main indication for hysterectomy, and represent a costly public health burden. The objectives of the analysis were to evaluate patients' eligibility for MRgHIFU treatment of symptomatic uterine fibroids and the technical success, safety, effectiveness, and durability of this treatment. The review also compared the safety and effectiveness of MRgHIFU with other minimally invasive uterine-preserving treatments and surgeries for uterine fibroids. A literature search was performed on March 27, 2014, using Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid EMBASE, EBSCO Cumulative Index to Nursing & Allied Health Literature (CINAHL), and EBM Reviews, for studies published from January 1, 2000, to March 27, 2014. The evidence review identified 2 systematic reviews, 2 RCTs, 45 cohort study reports, and 19 case reports involving HIFU treatment of symptomatic uterine fibroids. Eligibility for MRgHIFU treatment was variable, ranging from 14% to 74%. In clinical cohort studies involving 1,594 patients, 26 major complications (1.6%) were reported. MRgHIFU resulted in statistically and clinically significant reductions in fibroid-related symptoms in studies conducted in 10 countries, although few involved follow-up longer than 1 year. Retreatment rates following MRgHIFU were higher in early clinical studies involving regulated restrictions in the extent of fibroid ablation than in later reports involving near-complete ablation. Emergent interventions, however, were rare. Although a desire for fertility was an exclusion criteria for treatment, spontaneous term pregnancies did occur following HIFU. There were no randomized trials comparing MRgHIFU and

  14. Intercostal high intensity focused ultrasound for liver ablation: The influence of beam shaping on sonication efficacy and near-field risks

    International Nuclear Information System (INIS)

    Greef, M. de; Wijlemans, J. W.; Bartels, L. W.; Moonen, C. T. W.; Ries, M.; Schubert, G.; Koskela, J.

    2015-01-01

    Purpose: One of the major issues in high intensity focused ultrasound ablation of abdominal lesions is obstruction of the ultrasound beam by the thoracic cage. Beam shaping strategies have been shown by several authors to increase focal point intensity while limiting rib exposure. However, as rib obstruction leaves only part of the aperture available for energy transmission, conserving total emitted acoustic power, the intensity in the near-field tissues inherently increases after beam shaping. Despite of effective rib sparing, those tissues are therefore subjected to increased risk of thermal damage. In this study, for a number of clinically representative intercostal sonication geometries, modeling clinically available hardware, the effect of beam shaping on both the exposure of the ribs and near-field to acoustic energy was evaluated and the implications for the volumetric ablation rate were addressed. Methods: A relationship between rib temperature rise and acoustic energy density was established by means of in vivo MR thermometry and simulations of the incident acoustic energy for the corresponding anatomies. This relationship was used for interpretation of rib exposure in subsequent numerical simulations in which rib spacing, focal point placement, and the focal point trajectory were varied. The time required to heat a targeted region to 65 °C was determined without and with the application of beam shaping. The required sonication time was used to calculate the acoustic energy density at the fat–muscle interface and at the surface of the ribs. At the fat–muscle interface, exposure was compared to available literature data and rib exposure was interpreted based on the earlier obtained relation between measured temperature rise and simulated acoustic energy density. To estimate the volumetric ablation rate, the cool-down time between periods of energy exposure was estimated using a time-averaged power limit of 100 kJ/h. Results: At the level of the ribs

  15. Intercostal high intensity focused ultrasound for liver ablation: The influence of beam shaping on sonication efficacy and near-field risks

    Energy Technology Data Exchange (ETDEWEB)

    Greef, M. de, E-mail: m.degreef@umcutrecht.nl; Wijlemans, J. W.; Bartels, L. W.; Moonen, C. T. W.; Ries, M. [Imaging Division, University Medical Center Utrecht, Utrecht 3508GA (Netherlands); Schubert, G.; Koskela, J. [Philips Healthcare, Vantaa FI-01511 (Finland)

    2015-08-15

    Purpose: One of the major issues in high intensity focused ultrasound ablation of abdominal lesions is obstruction of the ultrasound beam by the thoracic cage. Beam shaping strategies have been shown by several authors to increase focal point intensity while limiting rib exposure. However, as rib obstruction leaves only part of the aperture available for energy transmission, conserving total emitted acoustic power, the intensity in the near-field tissues inherently increases after beam shaping. Despite of effective rib sparing, those tissues are therefore subjected to increased risk of thermal damage. In this study, for a number of clinically representative intercostal sonication geometries, modeling clinically available hardware, the effect of beam shaping on both the exposure of the ribs and near-field to acoustic energy was evaluated and the implications for the volumetric ablation rate were addressed. Methods: A relationship between rib temperature rise and acoustic energy density was established by means of in vivo MR thermometry and simulations of the incident acoustic energy for the corresponding anatomies. This relationship was used for interpretation of rib exposure in subsequent numerical simulations in which rib spacing, focal point placement, and the focal point trajectory were varied. The time required to heat a targeted region to 65 °C was determined without and with the application of beam shaping. The required sonication time was used to calculate the acoustic energy density at the fat–muscle interface and at the surface of the ribs. At the fat–muscle interface, exposure was compared to available literature data and rib exposure was interpreted based on the earlier obtained relation between measured temperature rise and simulated acoustic energy density. To estimate the volumetric ablation rate, the cool-down time between periods of energy exposure was estimated using a time-averaged power limit of 100 kJ/h. Results: At the level of the ribs

  16. Moderate-to-deep sedation technique, using propofol and ketamine, allowing synchronised breathing for magnetic resonance high-intensity focused ultrasound (MR-HIFU) treatment for uterine fibroids : a pilot study

    NARCIS (Netherlands)

    Vaessen, Hermanus H B; Knuttel, F M; van Breugel, J M M; Ikink, M E; Dieleman, J M; van den Bosch, Maurice; Knape, J T A

    2017-01-01

    BACKGROUND: Magnetic resonance high-intensity focused ultrasound (MR-HIFU) treatment for uterine fibroids is rapidly gaining popularity as a treatment modality. This procedure is generally uncomfortable, painful, and requires minimal or absence of movement and an MR-HIFU synchronised breathing

  17. Focusing on Increasing Velocity during Heavy Resistance Knee Flexion Exercise Boosts Hamstring Muscle Activity in Chronic Stroke Patients

    Directory of Open Access Journals (Sweden)

    Jonas Vinstrup

    2016-01-01

    Full Text Available Background. Muscle strength is markedly reduced in stroke patients, which has negative implications for functional capacity and work ability. Different types of feedback during strength training exercises may alter neuromuscular activity and functional gains. Objective. To compare levels of muscle activity during conditions of blindfolding and intended high contraction speed with a normal condition of high-intensity knee flexions. Methods. Eighteen patients performed unilateral machine knee flexions with a 10-repetition maximum load. Surface electromyography (EMG was recorded from the quadrics and hamstring muscles and normalized to maximal EMG (nEMG of the nonparetic limb. Results. For the paretic leg, the speed condition showed higher values of muscle activity compared with the normal and blindfolded conditions for both biceps femoris and semitendinosus. Likewise, the speed condition showed higher co-contraction values compared with the normal and blindfolded conditions for the vastus lateralis. No differences were observed between exercise conditions for the nonparetic leg. Conclusion. Chronic stroke patients are capable of performing heavy resistance training with intended high speed of contraction. Focusing on speed during the concentric phase elicited higher levels of muscle activity of the hamstrings compared to normal and blindfolded conditions, which may have implications for regaining fast muscle strength in stroke survivors.

  18. Non-Invasive Targeted Peripheral Nerve Ablation Using 3D MR Neurography and MRI-Guided High-Intensity Focused Ultrasound (MR-HIFU): Pilot Study in a Swine Model.

    Science.gov (United States)

    Huisman, Merel; Staruch, Robert M; Ladouceur-Wodzak, Michelle; van den Bosch, Maurice A; Burns, Dennis K; Chhabra, Avneesh; Chopra, Rajiv

    2015-01-01

    Ultrasound (US)-guided high intensity focused ultrasound (HIFU) has been proposed for noninvasive treatment of neuropathic pain and has been investigated in in-vivo studies. However, ultrasound has important limitations regarding treatment guidance and temperature monitoring. Magnetic resonance (MR)-imaging guidance may overcome these limitations and MR-guided HIFU (MR-HIFU) has been used successfully for other clinical indications. The primary purpose of this study was to evaluate the feasibility of utilizing 3D MR neurography to identify and guide ablation of peripheral nerves using a clinical MR-HIFU system. Volumetric MR-HIFU was used to induce lesions in the peripheral nerves of the lower limbs in three pigs. Diffusion-prep MR neurography and T1-weighted images were utilized to identify the target, plan treatment and immediate post-treatment evaluation. For each treatment, one 8 or 12 mm diameter treatment cell was used (sonication duration 20 s and 36 s, power 160-300 W). Peripheral nerves were extracted < 3 hours after treatment. Ablation dimensions were calculated from thermal maps, post-contrast MRI and macroscopy. Histological analysis included standard H&E staining, Masson's trichrome and toluidine blue staining. All targeted peripheral nerves were identifiable on MR neurography and T1-weighted images and could be accurately ablated with a single exposure of focused ultrasound, with peak temperatures of 60.3 to 85.7°C. The lesion dimensions as measured on MR neurography were similar to the lesion dimensions as measured on CE-T1, thermal dose maps, and macroscopy. Histology indicated major hyperacute peripheral nerve damage, mostly confined to the location targeted for ablation. Our preliminary results indicate that targeted peripheral nerve ablation is feasible with MR-HIFU. Diffusion-prep 3D MR neurography has potential for guiding therapy procedures where either nerve targeting or avoidance is desired, and may also have potential for post

  19. Enhancing ablation effects of a microbubble-enhancing contrast agent ("SonoVue") in the treatment of uterine fibroids with high-intensity focused ultrasound: a randomized controlled trial.

    Science.gov (United States)

    Jiang, Nan; Xie, Bin; Zhang, Xin; He, Min; Li, Kequan; Bai, Jin; Wang, Zhibiao; He, Jia; Zhang, Lian

    2014-10-01

    To evaluate the role of the ultrasound contrast agent SonoVue in enhancing the ablation effects of ultrasound-guided high-intensity focused ultrasound (HIFU) on uterine fibroids. Eighty patients with solitary uterine fibroids at a single center were randomly assigned to a control or SonoVue group. Of these, 40 were treated using HIFU alone; 40 who were pretreated with SonoVue received a bolus before the HIFU procedure. All patients underwent magnetic resonance imaging (MRI) scan before and after HIFU treatment. The post-HIFU MRI showed the nonperfused volume (NPV) in all of the treated uterine fibroids; the mean fractional ablation (NPV ratio) was 90.4 ± 8.3 % (range 66.4-100 %) in the SonoVue group and 82.8 ± 13.3 % (range 53.4-100 %) in the control group. The frequency of massive gray-scale changes that occurred during HIFU was greater in the group that received SonoVue than the group that did not. The average sonication time to reach massive gray-scale changes was significantly shorter in the group receiving SonoVue than the group without SonoVue. The acoustic energy for treating 1 mm(3) of uterine fibroid was less in the SonoVue group than the control group. No any major complication occurred in this study. Based on the results of this randomized controlled trial, SonoVue could be safely used to enhance the effects of HIFU treatment for uterine fibroids.

  20. In vivo optimisation study for multi-baseline MR-based thermometry in the context of hyperthermia using MR-guided high intensity focused ultrasound for head and neck applications.

    Science.gov (United States)

    Pichardo, Samuel; Köhler, Max; Lee, Justin; Hynnyen, Kullervo

    2014-12-01

    In this in vivo study, the feasibility to perform hyperthermia treatments in the head and neck using magnetic resonance image-guided high intensity focused ultrasound (MRgHIFU) was established using a porcine acute model. Porcine specimens with a weight between 17 and 18 kg were treated in the omohyoid muscle in the neck. Hyperthermia was applied with a target temperature of 41 °C for 30 min using a Sonalleve MRgHIFU system. MR-based thermometry was calculated using water-proton resonance frequency shift and multi-baseline look-up tables indexed by peak-to-peak displacement (Dpp) measurements using a pencil-beam navigator. Three hyperthermia experiments were conducted at different Dpp values of 0.2, 1.0 and 3.0 mm. An optimisation study was carried out to establish the optimal parameters controlling the multi-baseline method that ensured a minimisation of spatial-average peak-to-peak temperature (TSA-pp) and temperature direct current bias (TSA-DC). The multi-baseline technique reduced considerably the noise on both TSA-pp and TSA-DC. The reduction of noise was more important when Dpp was higher. For Dpp = 3 mm the average (±standard deviation (SD)) of TSA-pp and TSA-DC was reduced from 4.5 (± 2.5) and 2.5 (±0.6) °C, respectively, to 0.8 (± 0.7) and 0.09 (± 0.2) °C. This in vivo study showed the level of noise in PRFS-based thermometry introduced by respiratory motion in the context of MRgHIFU hyperthermia treatment for head and neck and the feasibility of reducing this noise using a multi-baseline technique.

  1. Diffusion-weighted magnetic resonance imaging using different b-value combinations for the evaluation of treatment results after volumetric MR-guided high-intensity focused ultrasound ablation of uterine fibroids

    Energy Technology Data Exchange (ETDEWEB)

    Ikink, Marlijne E.; Voogt, Marianne J.; Bosch, Maurice A.A.J. van den; Nijenhuis, Robbert J. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Keserci, Bilgin [Samsung Medical Center, High-intensity Focused Ultrasound (HIFU) Center, Seoul (Korea, Republic of); Philips Healthcare, Advanced Science and Development, Seoul (Korea, Republic of); Kim, Young-sun [Samsung Medical Center, High-intensity Focused Ultrasound (HIFU) Center, Seoul (Korea, Republic of); Samsung Medical Center, Sunkyunkwan University, Department of Radiology and Center for Imaging Science, Seoul (Korea, Republic of); Vincken, Koen L.; Bartels, Lambertus W. [University Medical Center Utrecht, Department of Radiology and Image Sciences Institute, Utrecht (Netherlands)

    2014-09-15

    To assess the value of diffusion-weighted magnetic resonance imaging (DWI) and apparent diffusion coefficient (ADC) mapping using different b-value combinations for treatment evaluation after magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) of uterine fibroids. Fifty-six patients with 67 uterine fibroids were treated with volumetric MR-HIFU. Pre-treatment and post-treatment images were obtained using contrast-enhanced T1-weighted MRI (CE-T1WI) and DWI using b = 0, 200, 400, 600, 800 s/mm{sup 2}. ADC maps were generated using subsets of b-values to investigate the effects of tissue ablation on water diffusion and perfusion in fibroids treated with MR-HIFU. Four combinations of b-values were used: (1) all b-values; (2) b = 0, 200 s/mm{sup 2}; (3) b = 400, 600, 800 s/mm{sup 2}; and (4) b = 0, 800 s/mm{sup 2}. Using the lowest b-values (0 and 200 s/mm{sup 2}), the mean ADC value in the ablated tissue reduced significantly (p < 0.001) compared with baseline. Calculating the ADC value with the highest b-values (400, 600, 800 s/mm{sup 2}), the ADC increased significantly (p < 0.001) post-treatment. ADC maps calculated with the lowest b-values resulted in the best visual agreement of non-perfused fibroid tissue detected on CE images. Other b-value combinations and normal myometrium showed no difference in ADC after MR-HIFU treatment. A decrease in contrast agent uptake within the ablated region on CE-T1WI was correlated to a significantly decreased ADC when b = 0 and 200 s/mm{sup 2} were used. (orig.)

  2. Bone remodeling after MR imaging-guided high-intensity focused ultrasound ablation: evaluation with MR imaging, CT, Na(18)F-PET, and histopathologic examination in a swine model.

    Science.gov (United States)

    Bucknor, Matthew D; Rieke, Viola; Seo, Youngho; Horvai, Andrew E; Hawkins, Randall A; Majumdar, Sharmila; Link, Thomas M; Saeed, Maythem

    2015-02-01

    To serially monitor bone remodeling in the swine femur after magnetic resonance (MR) imaging-guided high-intensity focused ultrasound (HIFU) ablation with MR imaging, computed tomography (CT), sodium fluorine 18 (Na(18)F)-positron emission tomography (PET), and histopathologic examination, as a function of sonication energy. Experimental procedures received approval from the local institutional animal care and use committee. MR imaging-guided HIFU was used to create distal and proximal ablations in the right femurs of eight pigs. The energy used at the distal target was higher (mean, 419 J; range, 390-440 J) than that used at the proximal target (mean, 324 J; range, 300-360 J). Imaging was performed before and after ablation with 3.0-T MR imaging and 64-section CT. Animals were reevaluated at 3 and 6 weeks with MR imaging (n = 8), CT (n = 8), Na(18)F-PET (n = 4), and histopathologic examination (n = 4). Three-dimensional ablation lengths were measured on contrast material-enhanced MR images, and bone remodeling in the cortex was measured on CT images. Ablation sizes at MR imaging 3 and 6 weeks after MR imaging-guided HIFU ablation were similar between proximal (low-energy) and distal (high-energy) lesions (average, 8.7 × 21.9 × 16.4 mm). However, distal ablation lesions (n = 8) demonstrated evidence of subperiosteal new bone formation at CT, with a subtle focus of new ossification at 3 weeks and a larger focus of ossification at 6 weeks. New bone formation was associated with increased uptake at Na(18)F-PET in three of four animals; this was confirmed at histopathologic examination in four of four animals. MR imaging-guided HIFU ablation of bone may result in progressive remodeling, with both subcortical necrosis and subperiosteal new bone formation. This may be related to the use of high energies. MR imaging, CT, and PET are suitable noninvasive techniques to monitor bone remodeling after MR imaging-guided HIFU ablation. © RSNA, 2014.

  3. Bone Remodeling after MR Imaging–guided High-Intensity Focused Ultrasound Ablation: Evaluation with MR Imaging, CT, Na18F-PET, and Histopathologic Examination in a Swine Model

    Science.gov (United States)

    Rieke, Viola; Seo, Youngho; Horvai, Andrew E.; Hawkins, Randall A.; Majumdar, Sharmila; Link, Thomas M.; Saeed, Maythem

    2015-01-01

    Purpose To serially monitor bone remodeling in the swine femur after magnetic resonance (MR) imaging–guided high-intensity focused ultrasound (HIFU) ablation with MR imaging, computed tomography (CT), sodium fluorine 18 (Na18F)–positron emission tomography (PET), and histopathologic examination, as a function of sonication energy. Materials and Methods Experimental procedures received approval from the local institutional animal care and use committee. MR imaging–guided HIFU was used to create distal and proximal ablations in the right femurs of eight pigs. The energy used at the distal target was higher (mean, 419 J; range, 390–440 J) than that used at the proximal target (mean, 324 J; range, 300–360 J). Imaging was performed before and after ablation with 3.0-T MR imaging and 64-section CT. Animals were reevaluated at 3 and 6 weeks with MR imaging (n = 8), CT (n = 8), Na18F-PET (n = 4), and histopathologic examination (n = 4). Three-dimensional ablation lengths were measured on contrast material–enhanced MR images, and bone remodeling in the cortex was measured on CT images. Results Ablation sizes at MR imaging 3 and 6 weeks after MR imaging–guided HIFU ablation were similar between proximal (low-energy) and distal (high-energy) lesions (average, 8.7 × 21.9 × 16.4 mm). However, distal ablation lesions (n = 8) demonstrated evidence of subperiosteal new bone formation at CT, with a subtle focus of new ossification at 3 weeks and a larger focus of ossification at 6 weeks. New bone formation was associated with increased uptake at Na18F-PET in three of four animals; this was confirmed at histopathologic examination in four of four animals. Conclusion MR imaging–guided HIFU ablation of bone may result in progressive remodeling, with both subcortical necrosis and subperiosteal new bone formation. This may be related to the use of high energies. MR imaging, CT, and PET are suitable noninvasive techniques to monitor bone remodeling after MR imaging

  4. ATLAS Boosted Objects tagging performance

    CERN Document Server

    Ferreira de Lima, D E; The ATLAS collaboration

    2014-01-01

    In the session on the performance of jet substructure reconstruction and boosted object tagging. This first contribution focuses on boosted object tagging performance. Material includes the shower deconstruction CONF note (missed BOOST2013, public), the Boosted boson tagging note (ATL-PHYS-PUB-2014-004, public since April). New papers on W/Z dsicrimination or top tagging are unlikely.

  5. WE-EF-BRA-12: Magnetic Resonance- Guided High-Intensity Focused Ultrasound for Localized Ablation of Head and Neck Tissue Structures: A Feasibility Study in An Animal Model

    Energy Technology Data Exchange (ETDEWEB)

    Partanen, A [Philips Healthcare, Andover, Massachusets (United States); Ellens, N; Noureldine, S; Tufano, R [Johns Hopkins University School of Medicine, Baltimore, MD (United States); Burdette, E [Acoustic MedSystems Inc., Savoy, IL (United States); Farahani, K [National Cancer Institute, Bethesda, MD (United States)

    2015-06-15

    Purpose: High-intensity focused ultrasound (HIFU) ablation is feasible in the head and neck [1]. This study aims to expand upon these findings to assess the feasibility of treatment planning and monitoring via magnetic resonance imaging (MRI) guidance using a clinical MR-guided HIFU platform. Methods: Two 31 kg pigs were anaesthetized, shaved, and positioned prone on the HIFU table (Sonalleve, Philips Healthcare, Vantaa, Finland). The necks were acoustically coupled to the integrated transducer using gel pads and degassed water. MR imaging verified acoustic coupling and facilitated target selection in the thyroid and thymus. Targets were thermally ablated with 130–200 W of acoustic power over a period of 16 s at a frequency of 1.2 MHz while being monitored through real-time, multi-planar MR-thermometry. Contrast-enhanced MR imaging was used to assess treatment efficacy. Post-treatment, animals were euthanized and sonicated tissues were harvested for histology assessment. Results: MR-thermometry, post-contrast-imaging, and gross pathology demonstrated that the system was capable of causing localized thermal ablation in both the thyroid and the thymus without damaging the aerodigestive tract. In one animal, superficial bruising was observed in the ultrasound beam path. Otherwise, there were no adverse events. Analysis of the tissue histology found regions of damage consistent with acute thermal injury at the targeted locations. Conclusion: It is feasible to use a clinical MR-guided HIFU platform for extracorporeal ablation of porcine head and neck tissues. MR guidance and thermometry are sufficient to target and monitor treatment in the thyroid region, despite the presence of the inhomogeneous aerodigestive tract. Further study is necessary to assess efficacy and survival using a tumor model, and to examine what modifications should be made to the transducer positioning system and associated patient positioning aids to adapt it for clinical head and neck targets

  6. LHC Report: reaching high intensity

    CERN Document Server

    Jan Uythoven

    2015-01-01

    After both beams having been ramped to their full energy of 6.5 TeV, the last two weeks saw the beam commissioning process advancing on many fronts. An important milestone was achieved when operators succeeded in circulating a nominal-intensity bunch. During the operation, some sudden beam losses resulted in beam dumps at top energy, a problem that needed to be understood and resolved.   In 2015 the LHC will be circulating around 2800 bunches in each beam and each bunch will contain just over 1 x 1011 protons. Until a few days ago commissioning was taking place with single bunches of 5 x 109 protons. The first nominal bunch with an intensity of 1 x 1011 protons was injected on Tuesday, 21 April. In order to circulate such a high-intensity bunch safely, the whole protection system must be working correctly: collimators, which protect the aperture, are set at preliminary values known as coarse settings; all kicker magnets for injecting and extracting the beams are commissioned with beam an...

  7. High intensity heat pulse problem

    International Nuclear Information System (INIS)

    Yalamanchili, R.

    1977-01-01

    The use of finite-difference methods for the solution of partial differential equations is common in both design and research and development because of the advance of computers. The numerical methods for the unsteady heat diffusion equation received most attention not only because of heat transfer problems but also happened to be the basis for any study of parabolic partial differential equations. It is common to test the heat equation first even the methods developed for complex nonlinear parabolic partial differential equations arising in fluid mechanics or convective heat transfer. It is concluded that the finite-element method is conservative in both stability and monoscillation characteristics than the finite-difference method but not as conservative as the method of weighted-residuals. Since the finite-element is unique because of Gurtin's variational principle and numerous finite-differences can be constructed, it is found that some finite-difference schemes are better than the finite-element scheme in accuracy also. Therefore, further attention is focused here on finite-difference schemes only. Various physical problems are considered in the field of heat transfer. These include: numerous problems in steady and unsteady heat conduction; heat pulse problems, such as, plasma torch; problems arising from machining operations, such as, abrasive cut-off and surface grinding. (Auth.)

  8. Cyclotrons for high-intensity beams

    CERN Document Server

    Seidel, Mike

    2013-01-01

    This paper reviews the important physical and technological aspects of cyclotrons for the acceleration of high-intensity beams. Special emphasis is given to the discussion of beam loss mechanisms and extraction schemes.

  9. High Intensity Exercise in Multiple Sclerosis

    DEFF Research Database (Denmark)

    Wens, Inez; Dalgas, Ulrik; Vandenabeele, Frank

    2015-01-01

    composition, maximal endurance capacity and self-reported physical activity levels were assessed before and after 12 weeks. Results Compared to SED, 12 weeks of high intensity exercise increased mean fiber CSA (HITR: +21±7%, HCTR: +23±5%). Furthermore, fiber type I CSA increased in HCTR (+29±6%), whereas type......±5%) and lean tissue mass (+1.4±0.5%) only increased in HITR. Finally self-reported physical activity levels increased 73±19% and 86±27% in HCTR and HITR, respectively. Conclusion High intensity cardiovascular exercise combined with resistance training was safe, well tolerated and improved muscle contractile...... exercise groups that performed 12 weeks of a high intensity interval (HITR, n = 12) or high intensity continuous cardiovascular training (HCTR, n = 11), both in combination with resistance training. M.vastus lateralis fiber cross sectional area (CSA) and proportion, knee-flexor/extensor strength, body...

  10. High-Intensity Plasma Glass Melter

    Energy Technology Data Exchange (ETDEWEB)

    None

    2004-01-01

    Modular high-intensity plasma melter promises improved performance, reduced energy use, and lower emissions. The glass industry has used the same basic equipment for melting glass for the past 100 years.

  11. Overview of High Intensity Linac Programs in Europe

    CERN Document Server

    Garoby, R

    2004-01-01

    Recent years have seen a boost in the support by the European Union (EU) of accelerator research in Europe. Provided they coordinate their efforts and define common goals and strategies, laboratories and institutions from the member states can receive a financial support reaching 50% of the total project cost. In the field of High Intensity Linacs, the EU has already supported the EURISOL initiative for nuclear physics, which this year is applying for funding of a Design Study, and the development of linacs for Waste Transmutation. More recently, an initiative for high-energy physics has been approved, which includes a programme for the development of pulsed linac technologies. The coordination and synergy imposed by the EU rules increase the benefit of the allocated resources. Combined with the ongoing internal projects in the partner laboratories, these European initiatives represent a strong effort focussed towards the development of linac technologies. This paper summarises the requests from the various E...

  12. Pulsed Power Applications in High Intensity Proton Rings

    CERN Document Server

    Zhang, Wu; Ducimetière, Laurent; Fowler, Tony; Kawakubo, Tadamichi; Mertens, Volker; Sandberg, Jon; Shirakabe, Yoshihisa

    2005-01-01

    The pulsed power technology has been applied in particle accelerators and storage rings for over four decades. It is most commonly used in injection, extraction, beam manipulation, source, and focusing systems. These systems belong to the class of repetitive pulsed power. In this presentation, we review and discuss the history, present status, and future challenge of pulsed power applications in high intensity proton accelerators and storage rings.

  13. rf coaxial couplers for high-intensity linear accelerators

    International Nuclear Information System (INIS)

    Manca, J.J.; Knapp, E.A.

    1980-02-01

    Two rf coaxial couplers that are particularly suitable for intertank connection of the disk-and-washer accelerating structure for use in high-intensity linear accelerators have been developed. These devices have very high coupling to the accelerating structure and very low rf power loss at the operating frequency, and they can be designed for any relative particle velocity β > 0.4. Focusing and monitoring devices can be located inside these couplers

  14. High-intensity laser application in Orthodontics

    OpenAIRE

    Sant’Anna, Eduardo Franzotti; Araújo, Mônica Tirre de Souza; Nojima, Lincoln Issamu; Cunha, Amanda Carneiro da; Silveira, Bruno Lopes da; Marquezan, Mariana

    2017-01-01

    ABSTRACT Introduction: In dental practice, low-level laser therapy (LLLT) and high-intensity laser therapy (HILT) are mainly used for dental surgery and biostimulation therapy. Within the Orthodontic specialty, while LLLT has been widely used to treat pain associated with orthodontic movement, accelerate bone regeneration after rapid maxillary expansion, and enhance orthodontic tooth movement, HILT, in turn, has been seen as an alternative for addressing soft tissue complications associated ...

  15. The high intensity neutron source FRANZ

    CERN Document Server

    Lederer, Claudia

    2014-01-01

    The Frankfurt neutron source of Stern Gerlach Zentrum FRANZ is currently under construction at the University of Frankfurt. At FRANZ, a high intensity neutron beam in the keV energy region will be produced by bombarding a $^7$Li target with a proton beam of several mA. These unprecedented high neutron fluxes will allow a number of neutron induced cross section measurements for the first time. Measurements can be performed by the time-of-flight and by the activation technique.

  16. Plasma-Immersion Formation of High-Intensity Ion Beams

    Science.gov (United States)

    Ryabchikov, A. I.; Anan'in, P. S.; Dektyarev, S. V.; Sivin, D. O.; Shevelev, A. E.

    2017-12-01

    For the first time, the possibility of forming high-intensity beams of low-energy metal and gas ions is demonstrated experimentally. The use of a hybrid system for ion-beam formation including plasmaimmersion extraction and ion acceleration and their subsequent ballistic focusing in an equipotential space with neutralization of the space charge of the beam made possible the pulse-periodic formation of titanium and nitrogen ion beams with an ion-current density of more than 1 A/cm2 and a pulsed power density of 2.6 kW/cm2.

  17. Spectral and photopic studies for high intensity discharge (HID lamps

    Directory of Open Access Journals (Sweden)

    Abd-Elmageed A.-E.A.

    2015-01-01

    Full Text Available Outdoor lighting sources such as High Intensity Discharge lamps (HID are common in these days. This research is focusing on the relation between the spectral power distribution and luminous efficiency function V(λ, which describes the average spectral sensitivity of human visual perception of brightness. The most useable HID lamps inside Egyptian markets are high pressure mercury (HPM, high pressure sodium (HPS and metal halide (MH. A set up based on single monochromator and integrating sphere for relative spectral power distribution and absolute luminous flux measurements are used, respectively. The accompanied standard uncertainties with the measurements are evaluated.

  18. High-intensity laser application in Orthodontics.

    Science.gov (United States)

    Sant'Anna, Eduardo Franzotti; Araújo, Mônica Tirre de Souza; Nojima, Lincoln Issamu; Cunha, Amanda Carneiro da; Silveira, Bruno Lopes da; Marquezan, Mariana

    2017-01-01

    In dental practice, low-level laser therapy (LLLT) and high-intensity laser therapy (HILT) are mainly used for dental surgery and biostimulation therapy. Within the Orthodontic specialty, while LLLT has been widely used to treat pain associated with orthodontic movement, accelerate bone regeneration after rapid maxillary expansion, and enhance orthodontic tooth movement, HILT, in turn, has been seen as an alternative for addressing soft tissue complications associated to orthodontic treatment. The aim of this study is to discuss HILT applications in orthodontic treatment. This study describes the use of HILT in surgical treatments such as gingivectomy, ulotomy, ulectomy, fiberotomy, labial and lingual frenectomies, as well as hard tissue and other dental restorative materials applications. Despite the many applications for lasers in Orthodontics, they are still underused by Brazilian practitioners. However, it is quite likely that this demand will increase over the next years - following the trend in the USA, where laser therapies are more widely used.

  19. ARRONAX, a high intensity cyclotron in Nantes

    Energy Technology Data Exchange (ETDEWEB)

    Haddad, F.; Michel, N.; Guertin, A.; Martino, J. [Nantes Univ., SUBATECH, IN2P3-CNRS, Ecole des Mines de Nantes, 44 (France); Barbet, J.; Chatal, J.F. [Nantes Univ., Dept. de Recherche en Cancerologie, Inserm, U601, 44 (France)

    2008-07-01

    A cyclotron named ARRONAX is being built in Nantes (France). It is mainly devoted to radiochemistry and nuclear medicine research and will be operational during the last quarter of 2008. This machine will accelerate both protons and {alpha}-particles at high energy (up to 70 MeV) and high intensity (2 simultaneous proton beams with intensity up to 350 {mu}A). In nuclear medicine, these characteristics will allow the cyclotron to produce a large variety of radionuclides on a regular schedule and in sufficient amount to perform clinical trials. A priority list of 12 radioisotopes, which contains isotopes for therapeutic use as well as for PET imaging, has been established by an international scientific committee. In radiochemistry, a vertical pulsed {alpha}-beam will allow fundamental studies of radiolysis in aqueous media, which is of great interest for radiobiology and for nuclear waste management. (authors)

  20. A High Intensity Hadron Facility, AGS II

    International Nuclear Information System (INIS)

    Lee, Y.Y.; Lowenstein, D.I.

    1988-01-01

    We have present one of several possibilities for the evolution of the AGS complex into a high intensity hadron facility. One could consider other alternatives, such as using the AGS as the Collector and constructing a new 9-30 GeV machine. We believe the most responsible scenario must minimize the cost and downtime to the ongoing physics program. With a stepwise approach, starting with the Booster, the physics program can evolve without a single major commitment in funds. At each step an evaluation of the funds versus physics merit can be made. As a final aside, each upgrade at the AGS and Booster is presently being implemented to support an interleaved operation of both protons and ions. 1 fig., 6 tabs

  1. Project BOOST implementation: lessons learned.

    Science.gov (United States)

    Williams, Mark V; Li, Jing; Hansen, Luke O; Forth, Victoria; Budnitz, Tina; Greenwald, Jeffrey L; Howell, Eric; Halasyamani, Lakshmi; Vidyarthi, Arpana; Coleman, Eric A

    2014-07-01

    Enhancing care coordination and reducing hospital readmissions have been a focus of multiple quality improvement (QI) initiatives. Project BOOST (Better Outcomes by Optimizing Safe Transitions) aims to enhance the discharge transition from hospital to home. Previous research indicates that QI initiatives originating externally often face difficulties gaining momentum or effecting lasting change in a hospital. We performed a qualitative evaluation of Project BOOST implementation by examining the successes and failures experienced by six pilot sites. We also evaluated the unique physician mentoring component of this program. Finally, we examined the impact of intensification of the physician mentoring model on adoption of BOOST interventions in two later Illinois cohorts (27 hospitals). Qualitative analysis of six pilot hospitals used a process of methodological triangulation and analysis of the BOOST enrollment applications, the listserv, and content from telephone interviews. Evaluation of BOOST implementation at Illinois hospitals occurred via mid-year and year-end surveys. The identified common barriers included inadequate understanding of the current discharge process, insufficient administrative support, lack of protected time or dedicated resources, and lack of frontline staff buy-in. Facilitators of implementation included the mentor, a small beginning, teamwork, and proactive engagement of the patient. Notably, hospitals viewed their mentors as essential facilitators of change. Sites consistently commented that the individualized mentoring was extremely helpful and provided significant accountability and stimulated creativity. In the Illinois cohorts, the improved mentoring model showed more complete implementation of BOOST interventions. The implementation of Project BOOST was well received by hospitals, although sites faced substantial barriers consistent with other QI research reports. The unique mentorship element of Project BOOST proved extremely

  2. Ablation of high intensity focused ultrasound combined with SonoVue on rabbit VX2 liver tumors: assessment with conventional gray-scale US, conventional color/power Doppler US, contrast-enhanced color Doppler US, and contrast-enhanced pulse-inversion harmonic US.

    Science.gov (United States)

    Luo, Wen; Zhou, Xiaodong; He, Guangbin; Li, Qiuyang; Zheng, Xiaoying; Fan, Zhiyong; Liu, Qing; Yu, Ming; Han, Zenghui; Zhang, Jun; Qian, Yunqiu

    2008-10-01

    We investigated effects of high intensity focused ultrasound (HIFU) combined with contrast agent SonoVue on rabbit VX2 liver tumors by using conventional gray-scale ultrasonography (US), color/power Doppler (CD/PD) US, contrast-enhanced color Doppler (CE CD) US, and contrast-enhanced pulse-inversion harmonic (CE PIH) US. Fourteen days after implantation of VX2 tumors in livers of 50 rabbits, animals were randomly separated into two groups. Based on principles of HIFU, the volume of the tumor was divided into several parallel "planes" to be ablated. Before ablation on each "plane," 0.2 mL SonoVue was injected in bolus via ear veins of rabbits in group II and normal saline solution was administrated in group I. Conventional gray-scale US, CD US, PD US, CE CD US, and CE PIH US were performed before and after ablation. Twenty-three surviving rabbits in each group underwent HIFU ablation. Conventional gray-scale US showed ablated areas diffusely hyperechoic. On CE PIH US, coagulated areas presented perfusion defect. Both conventional gray-scale US and CE PIH US showed the ablated volume in group II was larger than that in group I. CD US and PD US demonstrated residual vessels in periphery ablated areas in group I, but no residual vessels in group II. CE CD US and CE PIH US depicted less residual vessels in periphery ablated areas in group II than that in group I. By enlarging ablated volume of tissue and reducing residual vessels, effects of HIFU ablation on rabbit VX2 liver tumors were enhanced by contrast agent SonoVue.

  3. High intensity neutrino oscillation facilities in Europe

    CERN Document Server

    Edgecock, T.R.; Davenne, T.; Densham, C.; Fitton, M.; Kelliher, D.; Loveridge, P.; Machida, S.; Prior, C.; Rogers, C.; Rooney, M.; Thomason, J.; Wilcox, D.; Wildner, E.; Efthymiopoulos, I.; Garoby, R.; Gilardoni, S.; Hansen, C.; Benedetto, E.; Jensen, E.; Kosmicki, A.; Martini, M.; Osborne, J.; Prior, G.; Stora, T.; Melo-Mendonca, T.; Vlachoudis, V.; Waaijer, C.; Cupial, P.; Chancé, A.; Longhin, A.; Payet, J.; Zito, M.; Baussan, E.; Bobeth, C.; Bouquerel, E.; Dracos, M.; Gaudiot, G.; Lepers, B.; Osswald, F.; Poussot, P.; Vassilopoulos, N.; Wurtz, J.; Zeter, V.; Bielski, J.; Kozien, M.; Lacny, L.; Skoczen, B.; Szybinski, B.; Ustrzycka, A.; Wroblewski, A.; Marie-Jeanne, M.; Balint, P.; Fourel, C.; Giraud, J.; Jacob, J.; Lamy, T.; Latrasse, L.; Sortais, P.; Thuillier, T.; Mitrofanov, S.; Loiselet, M.; Keutgen, Th.; Delbar, Th.; Debray, F.; Trophine, C.; Veys, S.; Daversin, C.; Zorin, V.; Izotov, I.; Skalyga, V.; Burt, G.; Dexter, A.C.; Kravchuk, V.L.; Marchi, T.; Cinausero, M.; Gramegna, F.; De Angelis, G.; Prete, G.; Collazuol, G.; Laveder, M.; Mazzocco, M.; Mezzetto, M.; Signorini, C.; Vardaci, E.; Di Nitto, A.; Brondi, A.; La Rana, G.; Migliozzi, P.; Moro, R.; Palladino, V.; Gelli, N.; Berkovits, D.; Hass, M.; Hirsh, T.Y.; Schaumann, M.; Stahl, A.; Wehner, J.; Bross, A.; Kopp, J.; Neuffer, D.; Wands, R.; Bayes, R.; Laing, A.; Soler, P.; Agarwalla, S.K.; Cervera Villanueva, A.; Donini, A.; Ghosh, T.; Gómez Cadenas, J.J.; Hernández, P.; Martín-Albo, J.; Mena, O.; Burguet-Castell, J.; Agostino, L.; Buizza-Avanzini, M.; Marafini, M.; Patzak, T.; Tonazzo, A.; Duchesneau, D.; Mosca, L.; Bogomilov, M.; Karadzhov, Y.; Matev, R.; Tsenov, R.; Akhmedov, E.; Blennow, M.; Lindner, M.; Schwetz, T.; Fernández Martinez, E.; Maltoni, M.; Menéndez, J.; Giunti, C.; González García, M. C.; Salvado, J.; Coloma, P.; Huber, P.; Li, T.; López-Pavón, J.; Orme, C.; Pascoli, S.; Meloni, D.; Tang, J.; Winter, W.; Ohlsson, T.; Zhang, H.; Scotto-Lavina, L.; Terranova, F.; Bonesini, M.; Tortora, L.; Alekou, A.; Aslaninejad, M.; Bontoiu, C.; Kurup, A.; Jenner, L.J.; Long, K.; Pasternak, J.; Pozimski, J.; Back, J.J.; Harrison, P.; Beard, K.; Bogacz, A.; Berg, J.S.; Stratakis, D.; Witte, H.; Snopok, P.; Bliss, N.; Cordwell, M.; Moss, A.; Pattalwar, S.; Apollonio, M.

    2013-02-20

    The EUROnu project has studied three possible options for future, high intensity neutrino oscillation facilities in Europe. The first is a Super Beam, in which the neutrinos come from the decay of pions created by bombarding targets with a 4 MW proton beam from the CERN High Power Superconducting Proton Linac. The far detector for this facility is the 500 kt MEMPHYS water Cherenkov, located in the Fr\\'ejus tunnel. The second facility is the Neutrino Factory, in which the neutrinos come from the decay of {\\mu}+ and {\\mu}- beams in a storage ring. The far detector in this case is a 100 kt Magnetised Iron Neutrino Detector at a baseline of 2000 km. The third option is a Beta Beam, in which the neutrinos come from the decay of beta emitting isotopes, in particular 6He and 18Ne, also stored in a ring. The far detector is also the MEMPHYS detector in the Fr\\'ejus tunnel. EUROnu has undertaken conceptual designs of these facilities and studied the performance of the detectors. Based on this, it has determined the ph...

  4. High-intensity laser application in Orthodontics

    Directory of Open Access Journals (Sweden)

    Eduardo Franzotti Sant’Anna

    Full Text Available ABSTRACT Introduction: In dental practice, low-level laser therapy (LLLT and high-intensity laser therapy (HILT are mainly used for dental surgery and biostimulation therapy. Within the Orthodontic specialty, while LLLT has been widely used to treat pain associated with orthodontic movement, accelerate bone regeneration after rapid maxillary expansion, and enhance orthodontic tooth movement, HILT, in turn, has been seen as an alternative for addressing soft tissue complications associated to orthodontic treatment. Objective: The aim of this study is to discuss HILT applications in orthodontic treatment. Methods: This study describes the use of HILT in surgical treatments such as gingivectomy, ulotomy, ulectomy, fiberotomy, labial and lingual frenectomies, as well as hard tissue and other dental restorative materials applications. Conclusion: Despite the many applications for lasers in Orthodontics, they are still underused by Brazilian practitioners. However, it is quite likely that this demand will increase over the next years - following the trend in the USA, where laser therapies are more widely used.

  5. Beam halo in high-intensity hadron linacs

    International Nuclear Information System (INIS)

    Gerigk, F.

    2006-01-01

    This document aims to cover the most relevant mechanisms for the development of beam halo in high-intensity hadron linacs. The introduction outlines the various applications of high-intensity linacs and it will explain why, in the case of the CERN Superconducting Proton Linac (SPL) study a linac was chosen to provide a high-power beam, rather than a different kind of accelerator. The basic equations, needed for the understanding of halo development are derived and employed to study the effects of initial and distributed mismatch on high-current beams. The basic concepts of the particle-core model, envelope modes, parametric resonances, the free-energy approach, and the idea of core-core resonances are introduced and extended to study beams in realistic linac lattices. The approach taken is to study the behavior of beams not only in simplified theoretical focusing structures but to highlight the beam dynamics in realistic accelerators. All effects which are described and derived with simplified analytic models, are tested in realistic lattices and are thus related to observable effects in linear accelerators. This approach involves the use of high-performance particle tracking codes, which are needed to simulate the behavior of the outermost particles in distributions of up to 100 million macro particles. In the end a set of design rules are established and their impact on the design of a typical high-intensity machine, the CERN SPL, is shown. The examples given in this document refer to two different design evolutions of the SPL study: the first conceptual design report (SPL I) and the second conceptual design report (SPL II). (orig.)

  6. Beam halo in high-intensity hadron linacs

    Energy Technology Data Exchange (ETDEWEB)

    Gerigk, F.

    2006-12-21

    This document aims to cover the most relevant mechanisms for the development of beam halo in high-intensity hadron linacs. The introduction outlines the various applications of high-intensity linacs and it will explain why, in the case of the CERN Superconducting Proton Linac (SPL) study a linac was chosen to provide a high-power beam, rather than a different kind of accelerator. The basic equations, needed for the understanding of halo development are derived and employed to study the effects of initial and distributed mismatch on high-current beams. The basic concepts of the particle-core model, envelope modes, parametric resonances, the free-energy approach, and the idea of core-core resonances are introduced and extended to study beams in realistic linac lattices. The approach taken is to study the behavior of beams not only in simplified theoretical focusing structures but to highlight the beam dynamics in realistic accelerators. All effects which are described and derived with simplified analytic models, are tested in realistic lattices and are thus related to observable effects in linear accelerators. This approach involves the use of high-performance particle tracking codes, which are needed to simulate the behavior of the outermost particles in distributions of up to 100 million macro particles. In the end a set of design rules are established and their impact on the design of a typical high-intensity machine, the CERN SPL, is shown. The examples given in this document refer to two different design evolutions of the SPL study: the first conceptual design report (SPL I) and the second conceptual design report (SPL II). (orig.)

  7. High intensity neutrino oscillation facilities in Europe

    Directory of Open Access Journals (Sweden)

    T. R. Edgecock

    2013-02-01

    Full Text Available The EUROnu project has studied three possible options for future, high intensity neutrino oscillation facilities in Europe. The first is a Super Beam, in which the neutrinos come from the decay of pions created by bombarding targets with a 4 MW proton beam from the CERN High Power Superconducting Proton Linac. The far detector for this facility is the 500 kt MEMPHYS water Cherenkov, located in the Fréjus tunnel. The second facility is the Neutrino Factory, in which the neutrinos come from the decay of μ^{+} and μ^{-} beams in a storage ring. The far detector in this case is a 100 kt magnetized iron neutrino detector at a baseline of 2000 km. The third option is a Beta Beam, in which the neutrinos come from the decay of beta emitting isotopes, in particular ^{6}He and ^{18}Ne, also stored in a ring. The far detector is also the MEMPHYS detector in the Fréjus tunnel. EUROnu has undertaken conceptual designs of these facilities and studied the performance of the detectors. Based on this, it has determined the physics reach of each facility, in particular for the measurement of CP violation in the lepton sector, and estimated the cost of construction. These have demonstrated that the best facility to build is the Neutrino Factory. However, if a powerful proton driver is constructed for another purpose or if the MEMPHYS detector is built for astroparticle physics, the Super Beam also becomes very attractive.

  8. ORBIT : BEAM DYNAMICS CALCULATIONS FOR HIGH - INTENSITY RINGS

    International Nuclear Information System (INIS)

    HOLMES, J.A.; DANILOV, V.; GALAMBOS, J.; SHISHLO, A.; COUSINEAU, S.; CHOU, W.; MICHELOTTI, L.; OSTIGUY, F.; WEI, J.

    2002-01-01

    We are developing a computer code, ORBIT, specifically for beam dynamics calculations in high-intensity rings. Our approach allows detailed simulation of realistic accelerator problems. ORBIT is a particle-in-cell tracking code that transports bunches of interacting particles through a series of nodes representing elements, effects, or diagnostics that occur in the accelerator lattice. At present, ORBIT contains detailed models for strip-foil injection including painting and foil scattering; rf focusing and acceleration; transport through various magnetic elements; longitudinal and transverse impedances; longitudinal, transverse, and three-dimensional space charge forces; collimation and limiting apertures; and the calculation of many useful diagnostic quantities. ORBIT is an object-oriented code, written in C++ and utilizing a scripting interface for the convenience of the user. Ongoing improvements include the addition of a library of accelerator maps, BEAMLINE/MXYZPTLK the introduction of a treatment magnet errors and fringe fields; the conversion of the scripting interface to the standard scripting language, Python; and the parallelization of the computations using MPI. The ORBIT code is an open source, powerful, and convenient tool for studying beam dynamics in high-intensity rings

  9. A transparent vacuum window for high-intensity pulsed beams

    CERN Document Server

    Monteil, M; Veness, R

    2011-01-01

    The HiRadMat (High-Radiation to Materials) facility Ill will allow testing of accelerator components, in particular those of the Large Hadron Collider (LHC) at CERN, under the impact of high-intensity pulsed beams. To reach this intensity range, the beam will be focused on a focal point where the target to be tested is located. A 60 mm aperture vacuum window will separate the vacuum of the beam line which is kept under high vacuum 10(-8) mbar, from the test area which is at atmospheric pressure. This window has to resist collapse due to beam passage. The high-intensity of the beam means that typical materials used for standard vacuum windows (such as stainless steel, aluminium and titanium alloy) cannot endure the energy deposition induced by the beam passage. Therefore, a vacuum window has been designed to maintain the differential pressure whilst resisting collapse due to the beam impact on the window. In this paper, we will present calculations of the energy transfer from beam to window, the design of the ...

  10. A boost for the ISOLDE beams

    CERN Multimedia

    Corinne Pralavorio

    2015-01-01

    The first HIE-ISOLDE cryomodule was commissioned at the end of October. The radioactive ion beams can now be accelerated to 4.3 MeV per nucleon.   The ISOLDE beamline that supplies the Miniball array. The first HIE-ISOLDE cryomodule can be seen in the background, in its light-grey cryostat. ISOLDE is getting an energy boost. The first cryomodule of the new superconducting linear accelerator HIE-ISOLDE (High Intensity and Energy ISOLDE), located downstream of the REX-ISOLDE accelerator, increases the energy of the radioactive ion beams from 3 to 4.3 MeV per nucleon. It supplies the Miniball array, where an experiment using radioactive zinc ions (see box) began at the end of October. This is the first stage in the commissioning of HIE-ISOLDE. The facility will ultimately be equipped with four cryomodules that will accelerate the beams to 10 MeV per nucleon. Each cryomodule has five accelerating cavities and a solenoid, which focuses the beam. All of these components are superconducting. This first ...

  11. Wet high-intensity magnetic separation

    International Nuclear Information System (INIS)

    Levin, J.; Shanks, R.I.

    1980-01-01

    Miscellaneous laboratory tests (most of them on cyanide residues) were undertaken to supplement on-site pilot-plant work on wet high intensity magnetic separation (WHIMS). Initially, the main concern was with blockage of the matrix, and consideration was given to the use of a reverse-flushing system. The laboratory tests on this system were encouraging, but they were not of sufficiently long duration to be conclusive. The velocity of the pulp through the matrix is important, because it determines the capacity of the separator and the recovery obtainable. Of almost equal importance is the magnetic load, which affects the velocity of the pulp and the recovery. Typically, a recovery of 51 per cent of the uranium was reduced to one of 40 per cent as the magnetic load was increased from 25 to 100 g/l, while the pulp velocity decreased from 62 to 36 mm/s. There was some indication that, for the same pulp velocity, lower recoveries are obtained when free-fall feeding is used. Some benefit was observed in the application of WHIMS to coarsely ground ore; from a Blyvooruitzicht rod-mill product, 25 per cent of the total uranium was recovered when only 29 per cent of the rod-mill product (the finest portion) was treated. A similar recovery was made from 43 per cent of the rod-mill product from Stilfontein; a second stage of treatment after regrinding raised the overall recovery of uranium to 76,4 per cent. Recoveries of 55 and 42 per cent of the uranium were obtained in tests on two flotation tailings from Free State Geduld. In a determination of the mass magnetic susceptibilities of the constituents in a typical concentrate obtained by WHIMS, it was found that some 20 per cent of the magnetic product had a susceptibility of less than 5,4 X 10 -6 e.m.u. but contained 38 per cent of the uranium recovered by WHIMS. A few tests were conducted on different types of matrix. A matrix of spaced horizontal rods is recommended for possible future consideration [af

  12. Specificity of high-intensity intermittent action remains important to MMA athletes' physical conditioning: response to Paillard (2011).

    Science.gov (United States)

    Del Vecchio, Fabrício Boscolo; Franchini, Emerson

    2013-02-01

    This response to Paillard (2011) focuses on the intermittent nature of mixed martial arts (MMA). It also emphasizes that the main goal of MMA athletes is to win by knockout or submission and that these actions normally are high-intensity actions or preceded by high-intensity actions. Additionally, there is evidence that high-intensity intermittent exercise protocols are able to improve aerobic fitness. It is important only to adjust physical training to the athletes' techniques and tactics.

  13. Boosted top: experimental tools overview

    CERN Document Server

    Usai, Emanuele

    2015-01-01

    An overview of tools and methods for the reconstruction of high-boost top quark decays at the LHC is given in this report. The focus is on hadronic decays, in particular an overview of the current status of top quark taggers in physics analyses is presented. The most widely used jet substructure techniques, normally used in combination with top quark taggers, are reviewed. Special techniques to treat pileup in large cone jets are described, along with a comparison of the performance of several boosted top quark reconstruction techniques.

  14. Boosting foundations and algorithms

    CERN Document Server

    Schapire, Robert E

    2012-01-01

    Boosting is an approach to machine learning based on the idea of creating a highly accurate predictor by combining many weak and inaccurate "rules of thumb." A remarkably rich theory has evolved around boosting, with connections to a range of topics, including statistics, game theory, convex optimization, and information geometry. Boosting algorithms have also enjoyed practical success in such fields as biology, vision, and speech processing. At various times in its history, boosting has been perceived as mysterious, controversial, even paradoxical.

  15. Beam halo in high-intensity beams

    International Nuclear Information System (INIS)

    Wangler, T.P.

    1993-01-01

    In space-charge dominated beams the nonlinear space-charge forces produce a filamentation pattern, which in projection to the 2-D phase spaces results in a 2-component beam consisting of an inner core and a diffuse outer halo. The beam-halo is of concern for a next generation of cw, high-power proton linacs that could be applied to intense neutron generators for nuclear materials processing. The author describes what has been learned about beam halo and the evolution of space-charge dominated beams using numerical simulations of initial laminar beams in uniform linear focusing channels. Initial results are presented from a study of beam entropy for an intense space-charge dominated beam

  16. High intensity positron program at LLNL

    International Nuclear Information System (INIS)

    Asoka-Kumar, P.; Howell, R.H.; Stoeffl, W.

    1998-01-01

    Lawrence Livermore National Laboratory (LLNL) is the home of the world's highest current beam of keV positrons. The potential for establishing a national center for materials analysis using positron annihilation techniques around this capability is being actively pursued. The high LLNL beam current will enable investigations in several new areas. We are developing a positron microprobe that will produce a pulsed, focused positron beam for 3-dimensional scans of defect size and concentration with submicron resolution. Below we summarize the important design features of this microprobe. Several experimental end stations will be available that can utilize the high current beam with a time distribution determined by the electron linac pulse structure, quasi-continuous, or bunched at 20 MHz, and can operate in an electrostatic or (and) magnetostatic environment. Some of the planned early experiments are: two-dimensional angular correlation of annihilation radiation of thin films and buried interfaces, positron diffraction holography, positron induced desorption, and positron induced Auger spectra

  17. SemiBoost: boosting for semi-supervised learning.

    Science.gov (United States)

    Mallapragada, Pavan Kumar; Jin, Rong; Jain, Anil K; Liu, Yi

    2009-11-01

    Semi-supervised learning has attracted a significant amount of attention in pattern recognition and machine learning. Most previous studies have focused on designing special algorithms to effectively exploit the unlabeled data in conjunction with labeled data. Our goal is to improve the classification accuracy of any given supervised learning algorithm by using the available unlabeled examples. We call this as the Semi-supervised improvement problem, to distinguish the proposed approach from the existing approaches. We design a metasemi-supervised learning algorithm that wraps around the underlying supervised algorithm and improves its performance using unlabeled data. This problem is particularly important when we need to train a supervised learning algorithm with a limited number of labeled examples and a multitude of unlabeled examples. We present a boosting framework for semi-supervised learning, termed as SemiBoost. The key advantages of the proposed semi-supervised learning approach are: 1) performance improvement of any supervised learning algorithm with a multitude of unlabeled data, 2) efficient computation by the iterative boosting algorithm, and 3) exploiting both manifold and cluster assumption in training classification models. An empirical study on 16 different data sets and text categorization demonstrates that the proposed framework improves the performance of several commonly used supervised learning algorithms, given a large number of unlabeled examples. We also show that the performance of the proposed algorithm, SemiBoost, is comparable to the state-of-the-art semi-supervised learning algorithms.

  18. Extending statistical boosting. An overview of recent methodological developments.

    Science.gov (United States)

    Mayr, A; Binder, H; Gefeller, O; Schmid, M

    2014-01-01

    Boosting algorithms to simultaneously estimate and select predictor effects in statistical models have gained substantial interest during the last decade. This review highlights recent methodological developments regarding boosting algorithms for statistical modelling especially focusing on topics relevant for biomedical research. We suggest a unified framework for gradient boosting and likelihood-based boosting (statistical boosting) which have been addressed separately in the literature up to now. The methodological developments on statistical boosting during the last ten years can be grouped into three different lines of research: i) efforts to ensure variable selection leading to sparser models, ii) developments regarding different types of predictor effects and how to choose them, iii) approaches to extend the statistical boosting framework to new regression settings. Statistical boosting algorithms have been adapted to carry out unbiased variable selection and automated model choice during the fitting process and can nowadays be applied in almost any regression setting in combination with a large amount of different types of predictor effects.

  19. The impact of high intensity physical training on motor and non-motor symptoms in patients with Parkinson's disease (PIP)

    DEFF Research Database (Denmark)

    Morberg, Bo M; Jensen, Joakim; Bode, Matthias

    2014-01-01

    BACKGROUND: Parkinson's disease (PD) is a neurodegenerative disease caused by loss of dopaminergic nigrostriatal neurons. Several studies have investigated various physical interventions on PD. The effects of a high intensity exercise program with focus on resistance; cardio; equilibrium; and fle...

  20. Development of high intensity beam handling system, 4

    International Nuclear Information System (INIS)

    Yamanoi, Yutaka; Tanaka, Kazuhiro; Minakawa, Michifumi

    1992-01-01

    We have constructed the new counter experimental hall at the KEK 12 GeV Proton Synchrotron (KEK-PS) in order to handle high intensity primary proton beams of up to 1x10 3 pps (protons per second), which is one order of magnitude greater than the present beam intensity of the KEK-PS, 1x10 12 pps. New technologies for handling high-intensity beams have, then, been developed and employed in the construction of the new hall. A part of our R/D work on handling high intensity beams will be reported. (author)

  1. ELECTRON CLOUD EFFECTS IN HIGH INTENSITY PROTON ACCELERATORS

    International Nuclear Information System (INIS)

    Wei, J.; Macek, R.J.

    2002-01-01

    One of the primary concerns in the design and operation of high-intensity proton synchrotrons and accumulators is the electron cloud and associated beam loss and instabilities. Electron-cloud effects are observed at high-intensity proton machines like the Los Alamos National Laboratory's PSR and CERN's SPS, and investigated experimentally and theoretically. In the design of next-generation high-intensity proton accelerators like the Spallation Neutron Source ring, emphasis is made in minimizing electron production and in enhancing Landau damping. This paper reviews the present understanding of the electron-cloud effects and presents mitigation measures

  2. ELECTRON CLOUD EFFECTS IN HIGH INTENSITY PROTON ACCELERATORS.

    Energy Technology Data Exchange (ETDEWEB)

    WEI,J.; MACEK,R.J.

    2002-04-14

    One of the primary concerns in the design and operation of high-intensity proton synchrotrons and accumulators is the electron cloud and associated beam loss and instabilities. Electron-cloud effects are observed at high-intensity proton machines like the Los Alamos National Laboratory's PSR and CERN's SPS, and investigated experimentally and theoretically. In the design of next-generation high-intensity proton accelerators like the Spallation Neutron Source ring, emphasis is made in minimizing electron production and in enhancing Landau damping. This paper reviews the present understanding of the electron-cloud effects and presents mitigation measures.

  3. Energy compensation after sprint- and high-intensity interval training.

    Science.gov (United States)

    Schubert, Matthew M; Palumbo, Elyse; Seay, Rebekah F; Spain, Katie K; Clarke, Holly E

    2017-01-01

    Many individuals lose less weight than expected in response to exercise interventions when considering the increased energy expenditure of exercise (ExEE). This is due to energy compensation in response to ExEE, which may include increases in energy intake (EI) and decreases in non-exercise physical activity (NEPA). We examined the degree of energy compensation in healthy young men and women in response to interval training. Data were examined from a prior study in which 24 participants (mean age, BMI, & VO2max = 28 yrs, 27.7 kg•m-2, and 32 mL∙kg-1∙min-1) completed either 4 weeks of sprint-interval training or high-intensity interval training. Energy compensation was calculated from changes in body composition (air displacement plethysmography) and exercise energy expenditure was calculated from mean heart rate based on the heart rate-VO2 relationship. Differences between high (≥ 100%) and low (interval training. In agreement with prior work, increases in ΔVO2max and ΔNEPA were associated with lower energy compensation. Future studies should focus on identifying if a dose-response relationship for energy compensation exists in response to interval training, and what underlying mechanisms and participant traits contribute to the large variation between individuals.

  4. Apparatus for controlled mixing in a high intensity mixer

    International Nuclear Information System (INIS)

    Crocker, Z.; Gupta, V.P.

    1982-01-01

    An apparatus and a process is disclosed for controlled mixing of a mixable material in a high intensity mixer. The system enables instantaneous, precise and continual monitoring of a batch in a high intensity mixer which heretofore could not be achieved. The process comprises the steps of feeding a batch of material into a high intensity mixer, agitating the batch in the mixer, monitoring batch temperature separately from mixer temperature and discharging the batch from the mixer when the batch temperature reaches a final predetermined level. The apparatus includes means for monitoring batch temperature in a high intensity mixer separately from mixer temperature, and means responsive to the batch temperature to discharge the batch when the batch temperature reaches a final predetermined level

  5. Concept for a new high resolution high intensity diffractometer

    Energy Technology Data Exchange (ETDEWEB)

    Stuhr, U. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-09-01

    A concept of a new time-of-flight powder-diffractometer for a thermal neutral beam tube at SINQ is presented. The design of the instrument optimises the contradictory conditions of high intensity and high resolution. The high intensity is achieved by using many neutron pulses simultaneously. By analysing the time-angle-pattern of the detected neutrons an assignment of the neutrons to a single pulse is possible. (author) 3 figs., tab., refs.

  6. Case Study on Justification: High Intensity Discharge Lamps. Annex II

    International Nuclear Information System (INIS)

    2016-01-01

    High intensity discharge lamps produce bright white light of a high intensity in an energy efficient manner. These lamps are typically used in large numbers in public and professional settings such as shops, warehouses, hotels and offices. They are also used in outdoor applications to illuminate streets, buildings, statues, flags and gardens and further as architectural lighting. They also have applications associated with film projection in cinemas, manufacture of semiconductors, fluorescence endoscopy and microscopy, schlieren photography, hologram projection, ultraviolet curing, sky beamers and car headlights. Some types of high intensity discharge lamp, as well as certain other consumer products for lighting, contain radioactive substances for functional reasons. The radionuclides that are typically incorporated into high intensity discharge lamps are 85 Kr and 232 Th. Given the wide range of uses, specific decisions on justification may be required for different applications. A small number of safety assessments for high intensity discharge lamps have been carried out and published. No published decisions at the national level specifically addressing the justification of the use of high intensity discharge lamps have been identified

  7. Learning Boost C++ libraries

    CERN Document Server

    Mukherjee, Arindam

    2015-01-01

    If you are a C++ programmer who has never used Boost libraries before, this book will get you up-to-speed with using them. Whether you are developing new C++ software or maintaining existing code written using Boost libraries, this hands-on introduction will help you decide on the right library and techniques to solve your practical programming problems.

  8. Upgrading the GANIL facilities for high-intensity heavy ion beams

    International Nuclear Information System (INIS)

    Baron, E.

    1995-01-01

    A new project, called THI, is underway at GANIL for taking advantage of the high intensities extracted from the 14 GHz ion source. The goal is to boost the present beam intensities by a factor of the order of 15 for light ion species up to Ar while coping with beam powers of several kW. The status of the numerous components of this upgrading is described, including non-interceptive beam diagnostics, beam loss detection, supervision of electric and magnetic supplies, thermal shielding, solutions for radiation and safety problems, movable stripper, etc. The status of a re-buncher to be placed between the two separated sector cyclotrons in order to ameliorate the extraction efficiency of the last cyclotron is also presented. (author)

  9. Repeated high-intensity exercise in professional rugby union.

    Science.gov (United States)

    Austin, Damien; Gabbett, Tim; Jenkins, David

    2011-07-01

    The aim of the present study was to describe the frequency, duration, and nature of repeated high-intensity exercise in Super 14 rugby union. Time-motion analysis was used during seven competition matches over the 2008 and 2009 Super 14 seasons; five players from each of four positional groups (front row forwards, back row forwards, inside backs, and outside backs) were assessed (20 players in total). A repeated high-intensity exercise bout was considered to involve three or more sprints, and/or tackles and/or scrum/ruck/maul activities within 21 s during the same passage of play. The range of repeated high-intensity exercise bouts for each group in a match was as follows: 11-18 for front row forwards, 11-21 for back row forwards, 13-18 for inside backs, and 2-11 for outside backs. The durations of the most intense repeated high-intensity exercise bouts for each position ranged from 53 s to 165 s and the minimum recovery periods between repeated high-intensity exercise bouts ranged from 25 s for the back row forwards to 64 s for the front row forwards. The present results show that repeated high-intensity exercise bouts vary in duration and activities relative to position but all players in a game will average at least 10 changes in activity in the most demanding bouts and complete at least one tackle and two sprints. The most intense periods of activity are likely to last as long as 120 s and as little as 25 s recovery may separate consecutive repeated high-intensity exercise bouts. The present findings can be used by coaches to prepare their players for the most demanding passages of play likely to be experienced in elite rugby union.

  10. Self-guiding of high-intensity laser pulses for laser wake field acceleration

    International Nuclear Information System (INIS)

    Umstader, D.; Liu, X.

    1992-01-01

    A means of self-guiding an ultrashort and high-intensity laser pulse is demonstrated both experimentally and numerically. Its relevance to the laser wake field accelerator concept is discussed. Self-focusing and multiple foci formation are observed when a high peak power (P>100 GW), 1 μm, subpicosecond laser is focused onto various gases (air or hydrogen). It appears to result from the combined effects of self-focusing by the gas, and de-focusing both by diffraction and the plasma formed in the central high-intensity region. Quasi-stationary computer simulations show the same multiple foci behavior as the experiments. The results suggest much larger nonlinear electronic susceptibilities of a gas near or undergoing ionization in the high field of the laser pulse. Although self-guiding of a laser beam by this mechanism appears to significantly extend its high-intensity focal region, small-scale self-focusing due to beam non-uniformity is currently a limitation

  11. Deep Incremental Boosting

    OpenAIRE

    Mosca, Alan; Magoulas, George D

    2017-01-01

    This paper introduces Deep Incremental Boosting, a new technique derived from AdaBoost, specifically adapted to work with Deep Learning methods, that reduces the required training time and improves generalisation. We draw inspiration from Transfer of Learning approaches to reduce the start-up time to training each incremental Ensemble member. We show a set of experiments that outlines some preliminary results on some common Deep Learning datasets and discuss the potential improvements Deep In...

  12. Performance of highway bridges during high intensity earthquakes ...

    African Journals Online (AJOL)

    Performance of highway bridges during high intensity earthquakes. ... Journal of Civil Engineering, JKUAT ... The earthquake incurred tremendous damage to infrastructure mostly highway bridges and buildings caused by fault ruptures, near-fault strong motion and inadequate unseating prevention mechanism. Damage to ...

  13. Simulation study of the high intensity S-Band photoinjector

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Xiongwei; Nakajima, Kazuhisa [High Energy Accelerator Research Organization, Tsukuba, Ibaraki (Japan)

    2001-10-01

    In this paper, we report the results of simulation study of the high intensity S-Band photoinjector. The aim of the simulation study is to transport high bunch charge with low emittance evolution. The simulation result shows that 7nC bunch with rms emittance 22.3 {pi} mm mrad can be outputted at the exit of photoinjector. (author)

  14. Annotated bibliography on high-intensity linear accelerators. [240 citations

    Energy Technology Data Exchange (ETDEWEB)

    Jameson, R.A.; Roybal, E.U.

    1978-01-01

    A technical bibliography covering subjects important to the design of high-intensity beam transport systems and linear accelerators is presented. Space charge and emittance growth are stressed. Subject and author concordances provide cross-reference to detailed citations, which include an abstract and notes on the material. The bibliography resides in a computer database that can be searched for key words and phrases.

  15. High-Intensity Interval Training for Improving Postprandial Hyperglycemia

    Science.gov (United States)

    Little, Jonathan P.; Francois, Monique E.

    2014-01-01

    High-intensity interval training (HIIT) has garnered attention in recent years as a time-efficient exercise option for improving cardiovascular and metabolic health. New research demonstrates that HIIT may be particularly effective for improving postprandial hyperglycemia in individuals with, or at risk for, type 2 diabetes (T2D). These findings…

  16. Reuse Recycler: High Intensity Proton Stacking at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, P. [Fermilab

    2016-07-17

    After a successful career as an antiproton storage and cooling ring, Recycler has been converted to a high intensity proton stacker for the Main Injector. We discuss the commissioning and operation of the Recycler in this new role, and the progress towards the 700 kW design goal.

  17. High-intensity exercise and recovery during short-term ...

    African Journals Online (AJOL)

    Thirty active but not sprint-trained male subjects were randomly assigned to 1 of 3 groups: creatine plus protein-carbohydrate formula (CRF); creatine only (CRE); and control (CON). All groups were exposed to the same high-intensity sprint exercise programme, 3 times per week for 30 days. Main outcome measures.

  18. The high intensity approximation applied to multiphoton ionization

    International Nuclear Information System (INIS)

    Brandi, H.S.; Davidovich, L.; Zagury, N.

    1980-08-01

    It is shown that the most commonly used high intensity approximations as applied to ionization by strong electromagnetic fields are related. The applicability of the steepest descent method in these approximations, and the relation between them and first-order perturbation theory, are also discussed. (Author) [pt

  19. Influence of high intensity ultrasound with different probe diameter ...

    African Journals Online (AJOL)

    The main goal of this research is to analyze the influence of ultrasonic probe diameters (7 and 10 mm) of high-intensity ultrasound with constant frequency (30 kHz) on the degree of homogenization (variance) of cow milk. Influence of different probe diameters on the physical properties of cow milk was also tested. Changes ...

  20. Drift tube suspension for high intensity linear accelerators

    International Nuclear Information System (INIS)

    Clark, D.C.; Frank, J.A.; Liska, D.J.; Potter, R.C.; Schamaun, R.G.

    1982-01-01

    The disclosure relates to a drift tube suspension for high intensity linear accelerators. The system comprises a series of box-sections girders independently adjustably mounted on a linear accelerator. A plurality of drift tube holding stems are individually adjustably mounted on each girder

  1. Kaon physics with a high-intensity proton driver

    CERN Document Server

    Belyaev, A; Ceccucci, Augusto; Chizhov, M V; D'Ambrosio, G; Dorokhov, A E; Ellis, Jonathan Richard; Gómez, M E; Hurth, Tobias; Isidori, Gino; Kalmus, George Ernest; Lola, S; Zuber, K

    2004-01-01

    We study opportunities for future high-precision experiments in kaon physics using a high-intensity proton driver, which could be part of the front-end of a muon storage ring complex. We discuss in particular the rare decays $K_L\\to\\pi^0\

  2. Development plan of basic technology for a high intensity proton linear accelerator

    International Nuclear Information System (INIS)

    Mizumoto, M.

    1990-01-01

    The national program called OMEGA (Option Making Extra Gains from Actinide and Fission Products) has started with the aim of promoting the research and development of the new technologies for nuclear waste partitioning and transmutation. As a part of this program, Japan Atomic Energy Research Institute, JAERI, has laid out several R and D plans for accelerator based actinide transmutation. The present article first outlines the status of the high intensity proton linear accelerator. Then it describes the time schedule for the development of a high intensity proton linac, focusing on the first step development (basic technology accelerator), second step development (engineering test accelerator, and third step development (commercial plant). It also outlines the conceptual design study and preliminary design calculations for basic technology accelerator, focusing on general consideration, ion source, radio frequency quadrupole, drift tube linac, and high beta linac. (N.K.)

  3. Frequency conversion of high-intensity, femtosecond laser pulses

    Energy Technology Data Exchange (ETDEWEB)

    Banks, P S

    1997-06-01

    Almost since the invention of the laser, frequency conversion of optical pulses via non- linear processes has been an area of active interest. However, third harmonic generation using ~(~1 (THG) in solids is an area that has not received much attention because of ma- terial damage limits. Recently, the short, high-intensity pulses possible with chirped-pulse amplification (CPA) laser systems allow the use of intensities on the order of 1 TW/cm2 in thin solids without damage. As a light source to examine single-crystal THG in solids and other high field inter- actions, the design and construction of a Ti:sapphire-based CPA laser system capable of ultimately producing peak powers of 100 TW is presented. Of special interest is a novel, all-reflective pulse stretcher design which can stretch a pulse temporally by a factor of 20,000. The stretcher design can also compensate for the added material dispersion due to propagation through the amplifier chain and produce transform-limited 45 fs pulses upon compression. A series of laser-pumped amplifiers brings the peak power up to the terawatt level at 10 Hz, and the design calls for additional amplifiers to bring the power level to the 100 TW level for single shot operation. The theory for frequency conversion of these short pulses is presented, focusing on conversion to the third harmonic in single crystals of BBO, KD*P, and d-LAP (deuterated I-arginine phosphate). Conversion efficiencies of up to 6% are obtained with 500 fs pulses at 1053 nm in a 3 mm thick BBO crystal at 200 GW/cm 2. Contributions to this process by unphasematched, cascaded second harmonic generation and sum frequency generation are shown to be very significant. The angular relationship between the two orders is used to measure the tensor elements of C = xt3)/4 with Crs = -1.8 x 1O-23 m2/V2 and .15Cri + .54Crs = 4.0 x 1O-23 m2/V2. Conversion efficiency in d-LAP is about 20% that in BBO and conversion efficiency in KD*P is 1% that of BBO. It is calculated

  4. Is high-intensity exercise better than moderate-intensity exercise for weight loss?

    Science.gov (United States)

    De Feo, P

    2013-11-01

    This viewpoint debates the state-of-the-art research focusing on the optimal intensity of the exercise programs for inducing a sustained weight or fat-mass loss in overweight/obese people. In our demanding society, the most attractive messages in the popular press are those promising the best results in a short time. This might explain the emphasis given by media to those scientific articles that report the efficacy on weight loss of exercise programs by their shorter duration and higher intensity. However, in the literature on overweight or obese people, there is little conclusive evidence for more favorable effects with high-intensity training than with continuous moderate-intensity exercise on body weight or fat mass loss. Since both exercise protocols have been demonstrated as useful to reduce body weight, the decision on the intensity of exercise prescription should be individualized and based on outcomes different from fat or weight loss. In this regard, there are pro and contra arguments for the prescription of high-intensity aerobic exercise in obese people. Among the pro arguments, is the demonstration that, in several studies, high-intensity training appears to induce superior improvements in aerobic fitness. Among the contra arguments to prescribe high-intensity exercise is the demonstration that prescribing a higher-intensity exercise decreases adherence and results in the completion of less exercise. Thus, a successful exercise program should be proposed at a moderate intensity and a low perceived effort because obese subjects who have low self-efficacy, poor mood status, and are not familiar with high-intensity workouts could easily drop out. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. BEAM HALO FORMATION IN HIGH-INTENSITY BEAMS.

    Energy Technology Data Exchange (ETDEWEB)

    FEDOTOV, A.V.

    2005-03-18

    Studies of beam halo became unavoidable feature of high-intensity machines where uncontrolled beam loss should be kept to extremely small level. For a well controlled stable beam such a loss is typically associated with the low density halo surrounding beam core. In order to minimize uncontrolled beam loss or improve performance of an accelerator, it is very important to understand what are the sources of halo formation in a specific machine of interest. The dominant mechanisms are, in fact, different in linear accelerators, circular machines or Energy Recovering Linacs (ERL). In this paper, we summarize basic mechanisms of halo formation in high-intensity beams and discuss their application to various types of accelerators of interest, such as linacs, rings and ERL.

  6. CW high intensity non-scaling FFAG proton drivers

    OpenAIRE

    Johnstone, C.; Berz, M.; Makino, K.; Snopok, P.

    2012-01-01

    Accelerators are playing increasingly important roles in basic science, technology, and medicine including nuclear power, industrial irradiation, material science, and neutrino production. Proton and light-ion accelerators in particular have many research, energy and medical applications, providing one of the most effective treatments for many types of cancer. Ultra high-intensity and high-energy (GeV) proton drivers are a critical technology for accelerator-driven sub-critical reactors (ADS)...

  7. Spallation neutron source and other high intensity froton sources

    International Nuclear Information System (INIS)

    Weiren Chou

    2003-01-01

    This lecture is an introduction to the design of a spallation neutron source and other high intensity proton sources. It discusses two different approaches: linac-based and synchrotron-based. The requirements and design concepts of each approach are presented. The advantages and disadvantages are compared. A brief review of existing machines and those under construction and proposed is also given. An R and D program is included in an appendix

  8. NUMERICAL METHODS FOR THE SIMULATION OF HIGH INTENSITY HADRON SYNCHROTRONS

    International Nuclear Information System (INIS)

    LUCCIO, A.; D'IMPERIO, N.; MALITSKY, N.

    2005-01-01

    Numerical algorithms for PIC simulation of beam dynamics in a high intensity synchrotron on a parallel computer are presented. We introduce numerical solvers of the Laplace-Poisson equation in the presence of walls, and algorithms to compute tunes and twiss functions in the presence of space charge forces. The working code for the simulation here presented is SIMBAD, that can be run as stand alone or as part of the UAL (Unified Accelerator Libraries) package

  9. Numerical methods for simulation of high-intensity hadron synchrotrons

    International Nuclear Information System (INIS)

    Luccio, Alfredo U.; D'Imperio, Nicholas; Malitsky, Nikolay

    2006-01-01

    Numerical algorithms for PIC simulation of beam dynamics in a high-intensity synchrotron on a parallel computer are presented. We introduce numerical solvers of the Laplace-Poisson equation in the presence of walls, and algorithms to compute tunes and twiss functions in the presence of space-charge forces. The working code for the simulation here presented is SIMBAD, that can be run as standalone or as part of the Unified Accelerator Libraries (UAL) package

  10. Numerical methods for simulation of high-intensity hadron synchrotrons

    Energy Technology Data Exchange (ETDEWEB)

    Luccio, Alfredo U. [Brookhaven National Laboratory, C-AD Department, Upton, NY 11973 (United States)]. E-mail: luccio@bnl.gov; D' Imperio, Nicholas [Brookhaven National Laboratory, C-AD Department, Upton, NY 11973 (United States); Malitsky, Nikolay [Brookhaven National Laboratory, C-AD Department, Upton, NY 11973 (United States)

    2006-06-01

    Numerical algorithms for PIC simulation of beam dynamics in a high-intensity synchrotron on a parallel computer are presented. We introduce numerical solvers of the Laplace-Poisson equation in the presence of walls, and algorithms to compute tunes and twiss functions in the presence of space-charge forces. The working code for the simulation here presented is SIMBAD, that can be run as standalone or as part of the Unified Accelerator Libraries (UAL) package.

  11. NUMERICAL METHODS FOR THE SIMULATION OF HIGH INTENSITY HADRON SYNCHROTRONS.

    Energy Technology Data Exchange (ETDEWEB)

    LUCCIO, A.; D' IMPERIO, N.; MALITSKY, N.

    2005-09-12

    Numerical algorithms for PIC simulation of beam dynamics in a high intensity synchrotron on a parallel computer are presented. We introduce numerical solvers of the Laplace-Poisson equation in the presence of walls, and algorithms to compute tunes and twiss functions in the presence of space charge forces. The working code for the simulation here presented is SIMBAD, that can be run as stand alone or as part of the UAL (Unified Accelerator Libraries) package.

  12. Evidence based exercise - clinical benefits of high intensity interval training.

    Science.gov (United States)

    Shiraev, Tim; Barclay, Gabriella

    2012-12-01

    Aerobic exercise has a marked impact on cardiovascular disease risk. Benefits include improved serum lipid profiles, blood pressure and inflammatory markers as well as reduced risk of stroke, acute coronary syndrome and overall cardiovascular mortality. Most exercise programs prescribed for fat reduction involve continuous, moderate aerobic exercise, as per Australian Heart Foundation clinical guidelines. This article describes the benefits of exercise for patients with cardiovascular and metabolic disease and details the numerous benefits of high intensity interval training (HIIT) in particular. Aerobic exercise has numerous benefits for high-risk populations and such benefits, especially weight loss, are amplified with HIIT. High intensity interval training involves repeatedly exercising at a high intensity for 30 seconds to several minutes, separated by 1-5 minutes of recovery (either no or low intensity exercise). HIT is associated with increased patient compliance and improved cardiovascular and metabolic outcomes and is suitable for implementation in both healthy and 'at risk' populations. Importantly, as some types of exercise are contraindicated in certain patient populations and HIIT is a complex concept for those unfamiliar to exercise, some patients may require specific assessment or instruction before commencing a HIIT program.

  13. Boosting China's research collaboration | IDRC - International ...

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

    Boosting China's research collaboration. Rong Li presenting. Rong Li. Research Awards ... “China's cooperation to date has also largely ignored the role of research collaboration,” he says. Li focused on what China's foreign ... It was my first time formally working abroad,” he says. “It will definitely benefit my future career.”.

  14. Electron cloud instability in high intensity proton rings

    Directory of Open Access Journals (Sweden)

    K. Ohmi

    2002-11-01

    Full Text Available An e^{-}p instability has been observed in some proton rings. The instability, which causes beam loss, limits the performance of the ring. The instability may be serious for 3 and 50 GeV proton storage rings in the Japan Proton Accelerator Research Complex (J-PARC. We study the e^{-}p instability in several high intensity proton storage rings operated in the world. This work informs J-PARC of the necessity to cure the instability, for example, by applying a TiN coating on the chamber surface.

  15. P-West High Intensity Secondary Beam Area Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Cox, A.; Currier, R.; Eartly, D.; Guthke, A.; Johnson, G.; Lee, D.; Dram, R.; Villegas, E.; Rest, J.; Tilles, E.; Vander Arend, P.

    1977-03-01

    This report gives the initial design parameters of a 1000 GeV High Intensity Superconducting Secondary Beam Laboratory to be situated in the Proton Area downstream of the existing Proton West experimental station. The area will provide Fermilab with a major capability for experimentation with pion and antiproton beams of intensities and of energies available at no other laboratory and with an electron beam with excellent spot size, intensity, and purity at energies far above that available at electron machines. Detailed beam design, area layouts, and cost estimates are presented, along with the design considerations.

  16. Investigation on Beam Dynamics Design of High-Intensity RFQs

    CERN Document Server

    Zhang, C

    2004-01-01

    Recently various potential uses of high-intensity beams bring new opportunities as well as challenges to RFQ accelerator research because of the new problems arising from the strong space-charge effects. Unconventional concepts of beam dynamics design, which surround the choice of basic parameters and the optimization of main dynamics parameters’ variation along the machine, are illustrated by the designing Peking University (PKU) Deuteron RFQ. An efficient tool of LANL RFQ Design Codes for beam dynamics simulation and analysis, RFQBAT, is introduced. Some quality criterions are also presented for evaluating design results.

  17. HELIOS: A high intensity chopper spectrometer at LANSCE

    Energy Technology Data Exchange (ETDEWEB)

    Mason, T.E. [Oak Ridge National Lab., TN (United States); Broholm, C. [Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Physics and Astronomy; Fultz, B. [California Inst. of Tech., Pasadena, CA (United States). Dept. of Materials Science] [and others

    1998-12-31

    A proposal to construct a high intensity chopper spectrometer at LANSCE as part of the SPSS upgrade project is discussed. HELIOS will be optimized for science requiring high sensitivity neutron spectroscopy. This includes studies of phonon density of states in small polycrystalline samples, magnetic excitations in quantum magnets and highly correlated electron systems, as well as parametric studies (as a function of pressure, temperature, or magnetic field) of S(Q,{omega}). By employing a compact design together with the use of supermirror guide in the incident flight path the neutron flux at HELIOS will be significantly higher than any other comparable instrument now operating.

  18. The joint project for high-intensity proton accelerators

    International Nuclear Information System (INIS)

    1999-08-01

    Japan Atomic Energy Research Institute (JAERI) and the High Energy Accelerator Research Organization (KEK) agreed to promote the joint project integrating both the Neutron Science Project (NSP) of JAERI and the Japan Hadron Facility Project (JHF) of KEK for comprehensive studies on basic science and technology using high-intensity proton accelerator. This document describes the joint proposal prepared by the Joint Project Team of JAERI and KEK to construct accelerators and research facilities necessary both for the NSP and the JHF at the site of JAERI Tokai Establishment. (author)

  19. HELIOS: A high intensity chopper spectrometer at LANSCE

    International Nuclear Information System (INIS)

    Mason, T.E.; Broholm, C.; Fultz, B.

    1998-01-01

    A proposal to construct a high intensity chopper spectrometer at LANSCE as part of the SPSS upgrade project is discussed. HELIOS will be optimized for science requiring high sensitivity neutron spectroscopy. This includes studies of phonon density of states in small polycrystalline samples, magnetic excitations in quantum magnets and highly correlated electron systems, as well as parametric studies (as a function of pressure, temperature, or magnetic field) of S(Q,ω). By employing a compact design together with the use of supermirror guide in the incident flight path the neutron flux at HELIOS will be significantly higher than any other comparable instrument now operating

  20. Proton and Ion Sources for High Intensity Accelerators

    CERN Multimedia

    Scrivens, R

    2004-01-01

    Future high intensity ion accelerators, including the Spallation Neutron Source (SNS), the European Spallation Source (ESS), the Superconducting Proton Linac (SPL) etc, will require high current and high duty factor sources for protons and negative hydrogen ions. In order to achieve these goals, a comparison of the Electron Cyclotron Resonance, radio-frequency and Penning ion sources, among others, will be made. For each of these source types, the present operational sources will be compared to the state-of-the-art research devices with special attention given to reliability and availability. Finally, the future research and development aims will be discussed.

  1. Multi-energy ion implantation from high-intensity laser

    Czech Academy of Sciences Publication Activity Database

    Cutroneo, Mariapompea; Torrisi, L.; Ullschmied, Jiří; Dudžák, Roman

    2016-01-01

    Roč. 61, č. 2 (2016), s. 109-113 ISSN 0029-5922. [PLASMA 2015 : International Conference on Research and Applications of Plasmas. Warsaw, 07.09.2015-11.09.2015] R&D Projects: GA MŠk(CZ) LM2011019; GA ČR(CZ) GBP108/12/G108 Institutional support: RVO:61389021 ; RVO:61389005 Keywords : high-intensity laser * implantation * material modification Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders; BL - Plasma and Gas Discharge Physics (UFP-V) Impact factor: 0.760, year: 2016

  2. Injection and capture simulations for a high intensity proton synchrotron

    International Nuclear Information System (INIS)

    Cho, Y.; Lessner, E.; Symon, K.; Univ. of Wisconsin, Madison, WI

    1994-01-01

    The injection and capture processes in a high intensity, rapid cycling, proton synchrotron are simulated by numerical integration. The equations of motion suitable for rapid numerical simulation are derived so as to maintain symplecticity and second-order accuracy. By careful bookkeeping, the authors can, for each particle that is lost, determine its initial phase space coordinates. They use this information as a guide for different injection schemes and rf voltage programming, so that a minimum of particle losses and dilution are attained. A fairly accurate estimate of the space charge fields is required, as they influence considerably the particle distribution and reduce the capture efficiency. Since the beam is represented by a relatively coarse ensemble of macro particles, the authors study several methods of reducing the statistical fluctuations while retaining the fine structure (high intensity modulations) of the beam distribution. A pre-smoothing of the data is accomplished by the cloud-in-cell method. The program is checked by making sure that it gives correct answers in the absence of space charge, and that it reproduces the negative mass instability properly. Results of simulations for stationary distributions are compared to their analytical predictions. The capture efficiency for the rapid-cycling synchrotron is analyzed with respect to variations in the injected beam energy spread, bunch length, and rf programming

  3. TT40 Damage during 2004 High Intensity SPS Extraction

    CERN Document Server

    Goddard, B; Mertens, V; Uythoven, J; Wenninger, J; CERN. Geneva. AB Department

    2005-01-01

    During high intensity extraction on 25/10/04 an incident occurred in which the vacuum chamber of the TT40 magnet QTRF4002 was badly damaged. The beam was a 450 GeV full LHC injection batch of 3.4 1013 p+ in 288 bunches, and was extracted from SPS LSS4 with the wrong trajectory. Prior to the fatal extraction, problems had occurred over several hours during the setting-up, with beam-induced noise causing the extraction septum interlock to trip the power convertor, and also with the bumped beam position interlock. Deficiencies in the extraction setting-up process, in the interlocking and in the operational procedures used for the high-intensity test were contributing factors. In this note the incident causes are identified, the details reconstructed from the logged data, and the damage to the vacuum chamber analysed. The remedial measures which have already been taken are explained, and further recommendations made concerning the interlocking system performance and tests, as well as the operational procedures wh...

  4. Pedalling rate affects endurance performance during high-intensity cycling

    DEFF Research Database (Denmark)

    Nielsen, Jens Steen; Hansen, Ernst Albin; Sjøgaard, Gisela

    2004-01-01

    The purpose of this study into high-intensity cycling was to: (1) test the hypothesis that endurance time is longest at a freely chosen pedalling rate (FCPR), compared to pedalling rates 25% lower (FCPR-25) and higher (FCPR+25) than FCPR, and (2) investigate how physiological variables, such as m......The purpose of this study into high-intensity cycling was to: (1) test the hypothesis that endurance time is longest at a freely chosen pedalling rate (FCPR), compared to pedalling rates 25% lower (FCPR-25) and higher (FCPR+25) than FCPR, and (2) investigate how physiological variables......, such as muscle fibre type composition and power reserve, relate to endurance time. Twenty males underwent testing to determine their maximal oxygen uptake (VO(2max)), power output corresponding to 90% of VO(2max) at 80 rpm (W90), FCPR at W90, percentage of slow twitch muscle fibres (% MHC I), maximal leg power......, and endurance time at W90 with FCPR-25, FCPR, and FCPR+25. Power reserve was calculated as the difference between applied power output at a given pedalling rate and peak crank power at this same pedalling rate. W90 was 325 (47) W. FCPR at W90 was 78 (11) rpm, resulting in FCPR-25 being 59 (8) rpm and FCPR+25...

  5. High Intensity Focused Ultrasound: A Novel Model of Mild Traumatic Brain Injury

    Science.gov (United States)

    2013-11-07

    Berry A, Capone F, Giorgio M, Pelicci P, de Kloet E, et al . 2007. Deletion of the life span determinant p66Shc prevents age-dependent increases in...in humans. Limitations to animal research must be recognized as well. Shanks et al (78) argue that animal models are not predictive of responses in...brain injury in animals to model mild traumatic brain injuries (mTBI) in humans. Wahab et al (95) reported that HIFU can impair neural axonal

  6. Magnetic Resonance-Guided High Intensity Focused Ultrasound Ablation of Breast Cancer

    NARCIS (Netherlands)

    Knuttel, Floor; van den Bosch, Maurice A A J

    2016-01-01

    This chapter describes several aspects of MR-HIFU treatment for breast cancer. The current and future applications, technical developments and clinical results are discussed. MR-HIFU ablation is under investigation for the treatment of breast cancer, but is not yet ready for clinical implementation.

  7. Anti-inflammatory effect with high intensity focused ultrasound-mediated pulsatile delivery of diclofenac.

    Science.gov (United States)

    Wang, Chih-Yu; Yang, Chih-Hui; Lin, Yung-Sheng; Chen, Chih-Hsin; Huang, Keng-Shiang

    2012-02-01

    A pulsatile ultrasound controlled drug release platform with diclofenac-loaded alginate microcapsules (fabricated with a home-made electrostatic device, 75% embedded rate) was established to evaluate anti-inflammation efficiency. Better anti-inflammation efficiency was found using the ultrasound system and the drug delivery can be adjusted based on the programmed ultrasound cycle. The results of the in vitro study show that an approx. 30% higher drug release rate was obtained by using continuous ultrasound irradiation (9-Watt, 180 min), and an approx. 16% higher drug release rate was obtained by using pulsatile ultrasound irradiation (9-Watt, 60 min) compared to without ultrasound activation. For the in vivo study, the anti-inflammatory test with carrageenan-induced rat's paw edema shows that diclofenac-loaded microcapsules followed by ultrasound irradiation (9-Watt, 60 min) contributed to an 81% inhibition rate, which was significantly higher than diclofenac only (approx. 60% higher). In addition, because of their heat conducting properties, gold nanoparticles encapsulated in the diclofenac-loaded microcapsules resulted in better drug release efficiency, but tended to depress the anti-inflammation effect. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Heart ablation using a planar rectangular high intensity focused ultrasound transducer and MRI guidance

    Science.gov (United States)

    Couppis, Andreas; Damianou, Christakis; Ioannides, Kleanthis; Mylonas, Nicos; Iosif, Demitris; Kyriakou, Panagiotis; Lafon, Cyril; Chavrier, Francoise; Chapelon, Jean-Yves; Birer, Alain

    2011-09-01

    The aim of this study was to evaluate the performance of a flat rectangular (3×10 mm2) MRI compatible transducer operating at 5 MHz in creating deep lesions in heart at a depth of at least 15 mm. The size of thermal necrosis in heart tissue was estimated as a function of power and time using a simulation model. The system was then tested in freshly excised heart of pig and lamb. In this study we were able to create lesions 15 mm deep with an acoustic power of 6W for an exposure of approximately one minute. The contrast to noise ratio (CNR) between lesion and heart tissue was evaluated using Fast Spin Echo (FSE). With T1W FSE the CNR value was approximately 22. Maximum CNR was achieved with repetition times (TR) between 300 and 800 ms. With T2W FSE the corresponding CNR was approximately 13. The transducer was tested in rabbits in vivo and despite the motion of the heart; it was possible to create thermal lesions.

  9. Rehabilitation Using High-Intensity Physical Training and Long-Term Return-to-Work in Cancer Survivors

    NARCIS (Netherlands)

    Thijs, Karin M.; de Boer, Angela G. E. M.; Vreugdenhil, Gerard; van de Wouw, Agnès J.; Houterman, Saskia; Schep, Goof

    2012-01-01

    Introduction Due to large and increasing numbers of cancer survivors, long-term cancer-related health issues have become a major focus of attention. This study examined the relation between a high-intensity physical rehabilitation program and return-to-work in cancer survivors who had received

  10. Max Tech and Beyond: High-Intensity Discharge Lamps

    Energy Technology Data Exchange (ETDEWEB)

    Scholand, Michael

    2012-04-01

    High-intensity discharge (HID) lamps are most often found in industrial and commercial applications, and are the light source of choice in street and area lighting, and sports stadium illumination. HID lamps are produced in three types - mercury vapor (MV), high pressure sodium (HPS) and metal halide (MH). Of these, MV and MH are considered white-light sources (although the MV exhibits poor color rendering) and HPS produces a yellow-orange color light. A fourth lamp, low-pressure sodium (LPS), is not a HID lamp by definition, but it is used in similar applications and thus is often grouped with HID lamps. With the notable exception of MV which is comparatively inefficient and in decline in the US from both a sales and installed stock point of view; HPS, LPS and MH all have efficacies over 100 lumens per watt. The figure below presents the efficacy trends over time for commercially available HID lamps and LPS, starting with MV and LPS in 1930's followed by the development of HPS and MH in the 1960's. In HID lamps, light is generated by creating an electric arc between two electrodes in an arc tube. The particles in the arc are partially ionized, making them electrically conductive, and a light-emitting 'plasma' is created. This arc occurs within the arc tube, which for most HID lamps is enclosed within an evacuated outer bulb that thermally isolates and protects the hot arc tube from the surroundings. Unlike a fluorescent lamp that produces visible light through down-converting UV light with phosphors, the arc itself is the light source in an HID lamp, emitting visible radiation that is characteristic of the elements present in the plasma. Thus, the mixture of elements included in the arc tube is one critical factor determining the quality of the light emitted from the lamp, including its correlated color temperature (CCT) and color rendering index (CRI). Similar to fluorescent lamps, HID lamps require a ballast to start and maintain stable

  11. High Intensity Beam Issues in the CERN Proton Synchrotron

    CERN Document Server

    Aumon, Sandra; Rivkin, Leonid

    This PhD work is about limitations of high intensity proton beams observed in the CERN Proton Synchrotron (PS) and, in particular, about issues at injection and transition energies. With its 53 years, the CERN PS would have to operate beyond the limit of its performance to match the future requirements. Beam instabilities driven by transverse impedance and aperture restrictions are important issues for the operation and for the High-Luminosity LHC upgrade which foresees an intensity increase delivered by the injectors. The main subject of the thesis concerns the study of a fast transverse instability occurring at transition energy. The proton beams crossing this energy range are particularly sensitive to wake forces because of the slow synchrotron motion. This instability can cause a strong vertical emittance blow-up and severe losses in less than a synchrotron period. Experimental observations show that the particles at the peak density of the beam longitudinal distribution oscillate in the vertical plane du...

  12. Increased collection efficiency of LIFI high intensity electrodeless light source

    Science.gov (United States)

    Hafidi, Abdeslam; DeVincentis, Marc; Duelli, Markus; Gilliard, Richard

    2008-02-01

    Recently, RF driven electrodeless high intensity light sources have been implemented successfully in the projection display systems for HDTV and videowall applications. This paper presents advances made in the RF waveguide and electric field concentrator structures with the purpose of reducing effective arc size and increasing light collection. In addition, new optical designs are described that further improve system efficiency. The results of this work demonstrate that projection system light throughput is increased relative to previous implementations and performance is optimized for home theater and other front projector applications that maintain multi-year lifetime without re-lamping, complete spectral range, fast start times and high levels of dynamic contrast due to dimming flexibility in the light source system.

  13. High-Intensity Intermittent Exercise and Fat Loss

    Directory of Open Access Journals (Sweden)

    Stephen H. Boutcher

    2011-01-01

    Full Text Available The effect of regular aerobic exercise on body fat is negligible; however, other forms of exercise may have a greater impact on body composition. For example, emerging research examining high-intensity intermittent exercise (HIIE indicates that it may be more effective at reducing subcutaneous and abdominal body fat than other types of exercise. The mechanisms underlying the fat reduction induced by HIIE, however, are undetermined. Regular HIIE has been shown to significantly increase both aerobic and anaerobic fitness. HIIE also significantly lowers insulin resistance and results in a number of skeletal muscle adaptations that result in enhanced skeletal muscle fat oxidation and improved glucose tolerance. This review summarizes the results of HIIE studies on fat loss, fitness, insulin resistance, and skeletal muscle. Possible mechanisms underlying HIIE-induced fat loss and implications for the use of HIIE in the treatment and prevention of obesity are also discussed.

  14. Effect of high intensive football match on selected physiological variables

    Directory of Open Access Journals (Sweden)

    VINAY PAWAR

    2011-04-01

    Full Text Available The aim of the study was to find out the effect of high intensive football match on selected physiologicalvariables. For this purpose 20 male football players with the mean age 24.6 ± 1.74 year were acted as a subject.Oral body temperature, body weight & blood pressure were the selected as physiological variables, which weremeasured by digital thermometer, weight machine and digital blood pressure. All the data were collected fifteenminute prior and instantly after the end of the match. Paired “t” was used as a statically tool which revealedthat there were statistical significant was observed in all the selected physiological variables. The obtained “t”value for oral body temperature was 9.18, for body weight 7.12, for diastolic blood pressure 8.17 & for systolicblood pressure 8.88 was found between all the physiological variables before and after the high intensivefootball match.

  15. Low and high intensity beam monitoring and tracking

    CERN Document Server

    Lietti, D.; Bolognini, D.; Colombo, J.; Hasan, S.; Mattera, A.; Mozzanica, A.; Prest, M.; Schmitt, B.; Vallazza, E.

    Several detector types have been designed and assembled in order to monitor charged particle beams in a wide range of intensities: silicon microstrip detectors for high precision tracking (spatial resolution better than 5 μm), a scintillating fiber tracker with multianode photomultiplier readout for coarse but fast monitoring, a microstrip silicon detector readout by a counting ASIC to monitor very high intensity beams. These detectors and their readout electronics have been characterized at the BTF (Beam Test Facility) of the INFN National Laboratories of Frascati and used on the H8 line at the CERN SPS as tracking media for the data taking of the H8RD22 collaboration. The paper describes the results obtained in terms of spatial resolution and maximum counting rates.

  16. High intensity accelerator for a wide range of applications

    International Nuclear Information System (INIS)

    Conard, E.M.

    1994-01-01

    When looking at commercial applications of accelerators from a market point of view, it appears that a common accelerator design could meet different users' needs. This would benefit both the manufacturer and the user by multiplying the number of machines sold, thus lowering their cost and improving their quality. These applications include: radioisotope production for medical imaging (positron emission tomography), industrial imaging and non-destructive testing (e.g. neutron radiography, explosive and drug detection in luggage or freight). This paper investigates the needs of the various applications and defines their common denominator to establish suitable specifications (type of particles, energy, intensity). Different accelerator types (cyclotrons, linear accelerators and electrostatic machines) are reviewed and compared on performance and estimated costs. A high intensity tandem accelerator design is studied in more detail as it seems the most appropriate candidate. ((orig.))

  17. Fast damping in mismatched high intensity beam transportation

    Directory of Open Access Journals (Sweden)

    V. Variale

    2001-08-01

    Full Text Available A very fast damping of beam envelope oscillation amplitudes was recently observed in simulations of high intensity beam transport, through periodic FODO cells, in mismatched conditions [V. Variale, Nuovo Cimento Soc. Ital. Fis. 112A, 1571–1582 (1999 and T. Clauser et al., in Proceedings of the Particle Accelerator Conference, New York, 1999 (IEEE, Piscataway, NJ, 1999, p. 1779]. A Landau damping mechanism was proposed at the origin of observed effect. In this paper, to further investigate the source of this fast damping, extensive simulations have been carried out. The results presented here support the interpretation of the mechanism at the origin of the fast damping as a Landau damping effect.

  18. Relativistic electron mirrors from high intensity laser nanofoil interactions

    International Nuclear Information System (INIS)

    Kiefer, Daniel

    2012-01-01

    The reflection of a laser pulse from a mirror moving close to the speed of light could in principle create an X-ray pulse with unprecedented high brightness owing to the increase in photon energy and accompanying temporal compression by a factor of 4γ 2 , where γ is the Lorentz factor of the mirror. While this scheme is theoretically intriguingly simple and was first discussed by A. Einstein more than a century ago, the generation of a relativistic structure which acts as a mirror is demanding in many different aspects. Recently, the interaction of a high intensity laser pulse with a nanometer thin foil has raised great interest as it promises the creation of a dense, attosecond short, relativistic electron bunch capable of forming a mirror structure that scatters counter-propagating light coherently and shifts its frequency to higher photon energies. However, so far, this novel concept has been discussed only in theoretical studies using highly idealized interaction parameters. This thesis investigates the generation of a relativistic electron mirror from a nanometer foil with current state-of-the-art high intensity laser pulses and demonstrates for the first time the reflection from those structures in an experiment. To achieve this result, the electron acceleration from high intensity laser nanometer foil interactions was studied in a series of experiments using three inherently different high power laser systems and free-standing foils as thin as 3nm. A drastic increase in the electron energies was observed when reducing the target thickness from the micrometer to the nanometer scale. Quasi-monoenergetic electron beams were measured for the first time from ultrathin (≤5nm) foils, reaching energies up to ∝35MeV. The acceleration process was studied in simulations well-adapted to the experiments, indicating the transition from plasma to free electron dynamics as the target thickness is reduced to the few nanometer range. The experience gained from those

  19. Relativistic electron mirrors from high intensity laser nanofoil interactions

    Energy Technology Data Exchange (ETDEWEB)

    Kiefer, Daniel

    2012-12-21

    The reflection of a laser pulse from a mirror moving close to the speed of light could in principle create an X-ray pulse with unprecedented high brightness owing to the increase in photon energy and accompanying temporal compression by a factor of 4γ{sup 2}, where γ is the Lorentz factor of the mirror. While this scheme is theoretically intriguingly simple and was first discussed by A. Einstein more than a century ago, the generation of a relativistic structure which acts as a mirror is demanding in many different aspects. Recently, the interaction of a high intensity laser pulse with a nanometer thin foil has raised great interest as it promises the creation of a dense, attosecond short, relativistic electron bunch capable of forming a mirror structure that scatters counter-propagating light coherently and shifts its frequency to higher photon energies. However, so far, this novel concept has been discussed only in theoretical studies using highly idealized interaction parameters. This thesis investigates the generation of a relativistic electron mirror from a nanometer foil with current state-of-the-art high intensity laser pulses and demonstrates for the first time the reflection from those structures in an experiment. To achieve this result, the electron acceleration from high intensity laser nanometer foil interactions was studied in a series of experiments using three inherently different high power laser systems and free-standing foils as thin as 3nm. A drastic increase in the electron energies was observed when reducing the target thickness from the micrometer to the nanometer scale. Quasi-monoenergetic electron beams were measured for the first time from ultrathin (≤5nm) foils, reaching energies up to ∝35MeV. The acceleration process was studied in simulations well-adapted to the experiments, indicating the transition from plasma to free electron dynamics as the target thickness is reduced to the few nanometer range. The experience gained from those

  20. High intensity accelerator for a wide range of applications

    Science.gov (United States)

    Conard, E. Milo

    1994-12-01

    When looking at commercial applications of accelerators from a market point of view, it appears that a common accelerator design could meet different users' needs. This would benefit both the manufacturer and the user by multiplying the number of machines sold, thus lowering their cost and improving their quality. These applications include: radioisotope production for medical imaging (positron emission tomography), industrial imaging and non-destructive testing (e.g. neutron radiography, explosive and drug detection in luggage or freight). This paper investigates the needs of the various applications and defines their common denominator to establish suitable specifications (type of particles, energy, intensity). Different accelerator types (cyclotrons, linear accelerators and electrostatic machines) are reviewed and compared on performance and estimated costs. A high intensity tandem accelerator design is studied in more detail as it seems the most appropriate candidate.

  1. Fast Acting Optical Forces From Far Detuned, High Intensity Light

    Science.gov (United States)

    Corder, Christopher; Arnold, Brian; Hua, Xiang; Metcalf, Harold

    2015-05-01

    We are exploring fast acting, strong optical forces from standing wave light fields with high intensity and large detuning δ >> γ , where γ is the transition linewidth. We observe these fast acting forces on a time scale of a few times the excited state lifetime τ ≡ 1 / γ thus an atom may experience at most one or two spontaneous emission events. The dipole force is typically considered when the Rabi frequency Ω transverse velocity distribution of a beam of 23S He after a chosen interaction time with a perpendicular standing wave detuned from the 23S -->33P transition near 389 nm. The distribution shows velocity resonance effects that persist over a large range of Ω. We also simulate the experiment numerically using the Optical Bloch Equations and the results are consistent with our measurements. Supported by ONR and Dept. of Education GAANN

  2. What IAPT CBT High-Intensity Trainees Do After Training.

    Science.gov (United States)

    Liness, Sheena; Lea, Susan; Nestler, Steffen; Parker, Hannah; Clark, David M

    2017-01-01

    The UK Department of Health Improving Access to Psychological Therapies (IAPT) initiative set out to train a large number of therapists in cognitive behaviour therapies (CBT) for depression and anxiety disorders. Little is currently known about the retention of IAPT CBT trainees, or the use of CBT skills acquired on the course in the workplace after training has finished. This study set out to conduct a follow-up survey of past CBT trainees on the IAPT High Intensity CBT Course at the Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King's College London (KCL), one of the largest IAPT High Intensity courses in the UK. Past trainees (n = 212) across 6 cohorts (2008-2014 intakes) were contacted and invited to participate in a follow-up survey. A response rate of 92.5% (n = 196) was achieved. The vast majority of IAPT trainees continue to work in IAPT services posttraining (79%) and to practise CBT as their main therapy modality (94%); 61% have become CBT supervisors. A minority (23%) have progressed to other senior roles in the services. Shortcomings are reported in the use of out-of-office CBT interventions, the use of disorder-specific outcome measures and therapy recordings to inform therapy and supervision. Past trainees stay working in IAPT services and continue to use CBT methods taught on the course. Some NICE recommended treatment procedures that are likely to facilitate patients' recovery are not being routinely implemented across IAPT services. The results have implications for the continued roll out of the IAPT programme, and other future large scale training initiatives.

  3. Distribution-Specific Agnostic Boosting

    OpenAIRE

    Feldman, Vitaly

    2009-01-01

    We consider the problem of boosting the accuracy of weak learning algorithms in the agnostic learning framework of Haussler (1992) and Kearns et al. (1992). Known algorithms for this problem (Ben-David et al., 2001; Gavinsky, 2002; Kalai et al., 2008) follow the same strategy as boosting algorithms in the PAC model: the weak learner is executed on the same target function but over different distributions on the domain. We demonstrate boosting algorithms for the agnostic learning framework tha...

  4. Boost C++ application development cookbook

    CERN Document Server

    Polukhin, Antony

    2013-01-01

    This book follows a cookbook approach, with detailed and practical recipes that use Boost libraries.This book is great for developers new to Boost, and who are looking to improve their knowledge of Boost and see some undocumented details or tricks. It's assumed that you will have some experience in C++ already, as well being familiar with the basics of STL. A few chapters will require some previous knowledge of multithreading and networking. You are expected to have at least one good C++ compiler and compiled version of Boost (1.53.0 or later is recommended), which will be used during the exer

  5. Gradient Boosting Machines, A Tutorial

    Directory of Open Access Journals (Sweden)

    Alexey eNatekin

    2013-12-01

    Full Text Available Gradient boosting machines are a family of powerful machine-learning techniques that have shown considerable success in a wide range of practical applications. They are highly customizable to the particular needs of the application, like being learned with respect to different loss functions. This article gives a tutorial introduction into the methodology of gradient boosting methods. A theoretical information is complemented with many descriptive examples and illustrations which cover all the stages of the gradient boosting model design. Considerations on handling the model complexity are discussed. A set of practical examples of gradient boosting applications are presented and comprehensively analyzed.

  6. Inelastic scattering in condensed matter with high intensity Moessbauer radiation

    International Nuclear Information System (INIS)

    Yelon, W.B.; Schupp, G.

    1993-02-01

    The QUEGS facility at MURR has produced a number of new results and demonstrated the range of potential applications of high resolution, high intensity Moessbauer scattering. This work has been carried out by both MU and Purdue researchers and includes published results on Na, W, pentadecane, polydimethylsiloxane and other systems, manuscripts submitted on alkali halides (Phys. Rev. B) and accurate Moessbauer lineshape measurements (Phys. Rev. C), and manuscripts in preparation on glycerol, NiAl and Moessbauer spectra obtained by modulating a scattering crystal. Recently, new collaborations have been initiated which will substantially enhance our efforts. These are with W. Steiner (Vienna), G. Coddens (Saclay), and R. D. Taylor (Los Alamos). Steiner is experienced with Fe-57 Moessbauer scattering, while Coddens specializes in quasielastic neutron scattering; both of these areas naturally complement our work. R. D. Taylor has pioneered Moessbauer spectroscopy from the time of its discovery and has already made important contributions to our study of lattice dynamics and superconductivity for lead alloyed with small quantities of tin. At the same time, a significant instrument upgrade is underway, funded in part by the DOE-URIP program

  7. The WARP Code: Modeling High Intensity Ion Beams

    Science.gov (United States)

    Grote, David P.; Friedman, Alex; Vay, Jean-Luc; Haber, Irving

    2005-03-01

    The Warp code, developed for heavy-ion driven inertial fusion energy studies, is used to model high intensity ion (and electron) beams. Significant capability has been incorporated in Warp, allowing nearly all sections of an accelerator to be modeled, beginning with the source. Warp has as its core an explicit, three-dimensional, particle-in-cell model. Alongside this is a rich set of tools for describing the applied fields of the accelerator lattice, and embedded conducting surfaces (which are captured at sub-grid resolution). Also incorporated are models with reduced dimensionality: an axisymmetric model and a transverse "slice" model. The code takes advantage of modern programming techniques, including object orientation, parallelism, and scripting (via Python). It is at the forefront in the use of the computational technique of adaptive mesh refinement, which has been particularly successful in the area of diode and injector modeling, both steady-state and time-dependent. In the presentation, some of the major aspects of Warp will be overviewed, especially those that could be useful in modeling ECR sources. Warp has been benchmarked against both theory and experiment. Recent results will be presented showing good agreement of Warp with experimental results from the STS500 injector test stand. Additional information can be found on the web page http://hif.lbl.gov/theory/WARP_summary.html.

  8. Design alternatives for beam halo monitors in high intensity accelerators

    CERN Document Server

    Braun, H; Corsini, R; Lefèvre, T; Schulte, Daniel; Tecker, F A; Welsch, C P

    2005-01-01

    In future high intensity, high energy accelerators it must be ensured that particle losses are minimized as activation of the vacuum chambers or other components makes maintenance and upgrade work time consuming and costly. It is imperative to have a clear understanding of the mechanisms that can lead to halo formation and to have the possibility to test available theoretical models with an adequate experimental setup. Optical transition radiation (OTR) provides an interesting opportunity for linear real-time measurements of the transverse beam profile with a resolution which has been so far at best in the some μm range. However, the dynamic range of standard OTR systems is typically limited and needs to be improved for its application for halo measurements. In this contribution, the existing OTR system as it is installed in the CLIC test facility (CTF3) is analyzed and the contribution of each component to the final image quality discussed. Finally, possible halo measurement techniques based on OTR are pres...

  9. High Intensity Effects in the SNS Accumulator Ring

    International Nuclear Information System (INIS)

    Holmes, Jeffrey A.; Cousineau, Sarah M.; Danilov, Viatcheslav; Plum, Michael A.; Shishlo, Andrei P.

    2008-01-01

    Currently operating at 0.5 MW beam power on target, the Spallation Neutron Source (SNS) is already the world's most powerful pulsed neutron source. However, we are only one third of the way to full power. As we ramp toward full power, the control of the beam and beam loss in the ring will be critical. In addition to practical considerations, such as choice of operating point, painting scheme, RF bunching, and beam scattering, it may be necessary to understand and mitigate collective effects due to space charge, impedances, and electron clouds. At each stage of the power ramp-up, we use all available resources to understand and to minimize beam losses. From the standpoint of beam dynamics, the losses observed so far under normal operating conditions have not involved collective phenomena. We are now entering the intensity regime in which this may change. In dedicated high intensity beam studies, we have already observed resistive wall, extraction kicker impedance-driven, and electron cloud activities. The analysis and simulation of this data are important ongoing activities at SNS. This paper discusses the status of this work, as well as other considerations necessary to the successful full power operation of SNS.

  10. The WARP Code: Modeling High Intensity Ion Beams

    International Nuclear Information System (INIS)

    Grote, David P.; Friedman, Alex; Vay, Jean-Luc; Haber, Irving

    2005-01-01

    The Warp code, developed for heavy-ion driven inertial fusion energy studies, is used to model high intensity ion (and electron) beams. Significant capability has been incorporated in Warp, allowing nearly all sections of an accelerator to be modeled, beginning with the source. Warp has as its core an explicit, three-dimensional, particle-in-cell model. Alongside this is a rich set of tools for describing the applied fields of the accelerator lattice, and embedded conducting surfaces (which are captured at sub-grid resolution). Also incorporated are models with reduced dimensionality: an axisymmetric model and a transverse ''slice'' model. The code takes advantage of modern programming techniques, including object orientation, parallelism, and scripting (via Python). It is at the forefront in the use of the computational technique of adaptive mesh refinement, which has been particularly successful in the area of diode and injector modeling, both steady-state and time-dependent. In the presentation, some of the major aspects of Warp will be overviewed, especially those that could be useful in modeling ECR sources. Warp has been benchmarked against both theory and experiment. Recent results will be presented showing good agreement of Warp with experimental results from the STS500 injector test stand

  11. Formation of a high intensity low energy positron string

    Science.gov (United States)

    Donets, E. D.; Donets, E. E.; Syresin, E. M.; Itahashi, T.; Dubinov, A. E.

    2004-05-01

    The possibility of a high intensity low energy positron beam production is discussed. The proposed Positron String Trap (PST) is based on the principles and technology of the Electron String Ion Source (ESIS) developed in JINR during the last decade. A linear version of ESIS has been used successfully for the production of intense highly charged ion beams of various elements. Now the Tubular Electron String Ion Source (TESIS) concept is under study and this opens really new promising possibilities in physics and technology. In this report, we discuss the application of the tubular-type trap for the storage of positrons cooled to the cryogenic temperatures of 0.05 meV. It is intended that the positron flux at the energy of 1-5 eV, produced by the external source, is injected into the Tubular Positron Trap which has a similar construction as the TESIS. Then the low energy positrons are captured in the PST Penning trap and are cooled down because of their synchrotron radiation in the strong (5-10 T) applied magnetic field. It is expected that the proposed PST should permit storing and cooling to cryogenic temperature of up to 5×109 positrons. The accumulated cooled positrons can be used further for various physics applications, for example, antihydrogen production.

  12. Longitudinal tracking studies for a high intensity proton synchrotron

    International Nuclear Information System (INIS)

    Lessner, E.; Cho, Y.; Harkay, K.; Symon, K.

    1995-01-01

    Results from longitudinal tracking studies for a high intensity proton synchrotron designed for a 1-MW spallation source are presented. The machine delivers a proton beam of 0.5 mA time-averaged current at a repetition rate of 30 Hz. The accelerator is designed to have radiation levels that allow hands-on-maintenance. However, the high beam intensity causes strong space charge fields whose effects may lead to particle loss and longitudinal instabilities. The space charge fields modify the particle distribution, distort the stable bucket area and reduce the rf linear restoring force. Tracking simulations were conducted to analyze the space charge effects on the dynamics of the injection and acceleration processes and means to circumvent them. The tracking studies led to the establishment of the injected beam parameters and rf voltage program that minimized beam loss and longitudinal instabilities. Similar studies for a 10-GeV synchrotron that uses the 2-GeV synchrotron as its injector are also discussed

  13. Magnetoresistance oscillations induced by high-intensity terahertz radiation

    Science.gov (United States)

    Herrmann, T.; Kvon, Z. D.; Dmitriev, I. A.; Kozlov, D. A.; Jentzsch, B.; Schneider, M.; Schell, L.; Bel'kov, V. V.; Bayer, A.; Schuh, D.; Bougeard, D.; Kuczmik, T.; Oltscher, M.; Weiss, D.; Ganichev, S. D.

    2017-09-01

    We report on observation of pronounced terahertz radiation-induced magnetoresistivity oscillations in AlGaAs/GaAs two-dimensional electron systems, the terahertz analog of the microwave induced resistivity oscillations (MIRO). Applying high-power radiation of a pulsed molecular laser we demonstrate that MIRO, so far observed at low power only, are not destroyed even at very high intensities. Experiments with radiation intensity ranging over five orders of magnitude from 0.1 to 104W/cm 2 reveal high-power saturation of the MIRO amplitude, which is well described by an empirical fit function I /(1+I /Is) β with β ˜1 . The saturation intensity Is is of the order of tens of watts per square centimeter and increases by a factor of 6 by increasing the radiation frequency from 0.6 to 1.1 THz. The results are discussed in terms of microscopic mechanisms of MIRO and compared to nonlinear effects observed earlier at significantly lower excitation frequencies.

  14. Muscular soreness following prolonged intermittent high-intensity shuttle running.

    Science.gov (United States)

    Thompson, D; Nicholas, C W; Williams, C

    1999-05-01

    The aim of this study was to examine the impact of prolonged intermittent high-intensity shuttle running on soreness and markers of muscle damage. Sixteen males took part in the study, half of whom were assigned to a running group and half to a resting control group. The exercise protocol involved 90 min of intermittent shuttle running and walking (Loughborough Intermittent Shuttle Test: LIST), reflecting the activity pattern found in multiple-sprint sports such as soccer. Immediately after exercise, there was a significant increase (P < 0.05) in serum activities of creatine kinase and aspartate aminotransferase, and values remained above baseline for 48 h (P < 0.05). Median peak activities of creatine kinase and aspartate aminotransferase occurred 24 h post-exercise and were 774 and 43 U x l(-1), respectively. The intensity of general muscle soreness, and in the specific muscles investigated, was greater than baseline for 72 h after the shuttle test (P < 0.05), peaking 24-48 h post-exercise (P < 0.05). Muscle soreness was not correlated with either creatine kinase or aspartate aminotransferase activity. Soreness was most frequently reported in the hamstrings. Neither soreness nor serum enzyme activity changed in the controls over the 4 day observation period. It appears that unaccustomed performance of prolonged intermittent shuttle running produces a significant increase in both soreness and markers of muscle damage.

  15. Production and Studies of Photocathodes for High Intensity Electron Beams

    CERN Document Server

    Chevallay, E; Legros, P; Suberlucq, Guy; Trautner, H

    2000-01-01

    For short, high-intensity electron bunches, alkali-tellurides have proved to be a reliable photo-cathode material. Measurements of lifetimes in an rf gun of the CLIC Test Facility II at field strengths greater than 100 MV/m are presented. Before and after using them in this gun, the spectral response of the CS-Te and Rb-Te cathodes were determined with the help of an optical parametric oscillator. The behaviour of both materials can be described by Spicer's 3-step model. Whereas during the use the threshold for photo-emission in Cs-Te was shifted to higher proton energies, that of Rb-Te did not change. Our latest investigations on the stoichiometric ratio of the components are shown. The preparation of the photo-cathodes was monitored with 320 nm wavelength light , with the aim of improving the measurement sensitivity. The latest results on the protection of Cs-Te cathode surfaces with CsBr against pollution are summarized. New investigations on high mean current production are presented.,

  16. Formation of a high intensity low energy positron string

    International Nuclear Information System (INIS)

    Donets, E.D.; Donets, E.E.; Syresin, E.M.; Itahashi, T.; Dubinov, A.E.

    2004-01-01

    The possibility of a high intensity low energy positron beam production is discussed. The proposed Positron String Trap (PST) is based on the principles and technology of the Electron String Ion Source (ESIS) developed in JINR during the last decade. A linear version of ESIS has been used successfully for the production of intense highly charged ion beams of various elements. Now the Tubular Electron String Ion Source (TESIS) concept is under study and this opens really new promising possibilities in physics and technology. In this report, we discuss the application of the tubular-type trap for the storage of positrons cooled to the cryogenic temperatures of 0.05 meV. It is intended that the positron flux at the energy of 1-5 eV, produced by the external source, is injected into the Tubular Positron Trap which has a similar construction as the TESIS. Then the low energy positrons are captured in the PST Penning trap and are cooled down because of their synchrotron radiation in the strong (5-10 T) applied magnetic field. It is expected that the proposed PST should permit storing and cooling to cryogenic temperature of up to 5x10 9 positrons. The accumulated cooled positrons can be used further for various physics applications, for example, antihydrogen production

  17. Creatine kinase response to high-intensity aerobic exercise in adult-onset muscular dystrophy

    DEFF Research Database (Denmark)

    Andersen, Søren P; Sveen, Marie-Louise; Hansen, Regitze S

    2013-01-01

    We investigated the effect of high-intensity exercise on plasma creatine kinase (CK) in patients with muscular dystrophies.......We investigated the effect of high-intensity exercise on plasma creatine kinase (CK) in patients with muscular dystrophies....

  18. Compliance with High-Intensity Radiated Fields Regulations - Emitter's Perspective

    Science.gov (United States)

    Statman, Joseph; Jamnejad, Vahraz; Nguyen, Lee

    2012-01-01

    NASA's Deep Space Network (DSN) uses high-power transmitters on its large antennas to communicate with spacecraft of NASA and its partner agencies. The prime reflectors of the DSN antennas are parabolic, at 34m and 70m in diameter. The DSN transmitters radiate Continuous Wave (CW) signals at 20 kW - 500 kW at X-band and S-band frequencies. The combination of antenna reflector size and high frequency results in a very narrow beam with extensive oscillating near-field pattern. Another unique feature of the DSN antennas is that they (and the radiated beam) move mostly at very slow sidereal rate, essentially identical in magnitude and at the opposite direction of Earth rotation.The DSN is in the process of revamping its documentation to provide analysis of the High Intensity Radiation Fields (HIRF) environment resulting from radio frequency radiation from DSN antennas for comparison to FAA regulations regarding certification of HIRF protection as outlined in the FAA regulations on HIRF protection for aircraft electrical and electronic systems (Title 14, Code of Federal Regulations (14 CFR) [section sign][section sign] 23.1308, 25.1317, 27.1317, and 29.1317).This paper presents work done at JPL, in consultation with the FAA. The work includes analysis of the radiated field structure created by the unique DSN emitters (combination of transmitters and antennas) and comparing it to the fields defined in the environments in the FAA regulations. The paper identifies areas that required special attention, including the implications of the very narrow beam of the DSN emitters and the sidereal rate motion. The paper derives the maximum emitter power allowed without mitigation and the mitigation zones, where required.Finally, the paper presents summary of the results of the analyses of the DSN emitters and the resulting DSN process documentation.

  19. Effects of high-intensity interval training on canoeing performance.

    Science.gov (United States)

    Yang, Ming-Ta; Lee, Mien-Mien; Hsu, Shu-Ching; Chan, Kuei-Hui

    2017-08-01

    The purpose of this study was to compare the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) utilizing a canoeing ergometer on endurance determinants, as well as aerobic and anaerobic performances among flat-water canoeists. Fourteen well-trained male flat-water canoeists were divided into an HIIT group or an MICT group. All subjects performed a continuous graded exercise test (GXT) and three fixed-distance (200, 500, and 1000 m) performance tests on a canoeing ergometer to determine canoeing economy, peak oxygen uptake (VO 2 peak), and power at VO 2 peak, and to calculate the critical velocity (CV) and anaerobic work capacity before and after the training programmes. The training programme involved training on a canoeing ergometer three times per week for four weeks. HIIT consisted of seven 2 min canoeing bouts at an intensity of 90% VO 2 peak separated by 1 min of rest. The MICT group was trained at an intensity of 65% VO 2 peak continuously for 20 min. After four weeks of training, performance in the 200-m distance test and the power at VO 2 peak significantly improved in the HIIT group; performance in the 500 m and 1000 m distances and CV significantly improved in the MICT group. However, all variables were not significantly different between groups. It is concluded that HIIT for four weeks is an effective training strategy for improvement of short-distance canoeing performance. In contrast, MICT improves middle-distance canoeing performances and aerobic capacity.

  20. Inelastic scattering in condensed matter with high intensity Moessbauer radiation

    International Nuclear Information System (INIS)

    Yelon, W.B.; Schupp, G.

    1990-10-01

    We give a progress report for the work which has been carried out in the last three years with DOE support. A facility for high-intensity Moessbauer scattering is now fully operational at the University of Missouri Research Reactor (MURR) as well as facility at Purdue, using special isotopes produced at MURR. High precision, fundamental Moessbauer effect studies have been carried out using scattering to filter the unwanted radiation. These have led to a new Fourier transform method for describing Moessbauer effect (ME) lineshape and a direct method of fitting ME data to the convolution integral. These methods allow complete correction for source resonance self absorption (SRSA) and the accurate representation of interference effects that add an asymmetric component to the ME lines. We have begun applying these techniques to attenuated ME sources whose central peak has been attenuated by stationary resonant absorbers, to more precisely determine interference parameters and line-shape behavior in the resonance asymptotic region. This analysis is important to both the fundamental ME studies and to scattering studies for which a deconvolution is essential for extracting the correct recoilless fractions and interference parameters. A number of scattering studies have been successfully carried out including a study of the thermal diffuse scattering in Si, which led to an analysis of the resolution function for gamma-ray scattering. Also studied was the anharmonic motion in Na and the satellite reflection Debye-Waller factor in TaS 2 , which indicate phason rather than phonon behavior. We have begun quasielastic diffusion studies in viscous liquids and current results are summarized. These advances, coupled to our improvements in MIcrofoil Conversion Electron spectroscopy lay the foundation for the proposed research outlined in this request for a three-year renewal of DOE support

  1. Gamma scattering in condensed matter with high intensity Moessbauer radiation

    International Nuclear Information System (INIS)

    1990-01-01

    We give a progress report for the work which has been carried out in the last three years with DOE support. A facility for high-intensity Moessbauer scattering is now fully operational at the University of Missouri Research Reactor (MURR) as well as a facility at Purdue, using special isotopes produced at MURR. High precision, fundamental Moessbauer effect studies have been carried out using scattering to filter the unwanted radiation. These have led to a new Fourier transform method for describing Moessbauer effect (ME) lineshape and a direct method of fitting ME data to the convolution integral. These methods allow complete correction for source resonance self absorption (SRSA) and the accurate representation of interference effects that add an asymmetric component to the ME lines. We have begun applying these techniques to attenuated ME sources whose central peak has been attenuated by stationary resonant absorbers, to more precisely determine interference parameters and line-shape behavior in the resonance asymptotic region. This analysis is important to both the fundamental ME studies and to scattering studies for which a deconvolution is essential for extracting the correct recoilless fractions and interference parameters. A number of scattering studies have been successfully carried out including a study of the thermal diffuse scattering in Si, which led to an analysis of the resolution function for gamma-ray scattering. Also studied was the anharmonic motion in Na and the satellite reflection Debye-Waller factor in TaS 2 , which indicate phason rather than phonon behavior. We have begun quasielastic diffusion studies in viscous liquids and current results are summarized. These advances, coupled to our improvements in MIcrofoil Conversion Electron spectroscopy lay the foundation for the proposed research outlined in this request for a three-year renewal of DOE support

  2. Inelastic scattering in condensed matter with high intensity moessbauer radiation

    International Nuclear Information System (INIS)

    Yelon, W.B.; Schupp, G.

    1991-05-01

    We give a progress report for the work which has been carried out in the last three years with DOE support. A facility for high-intensity Moessbauer scattering is not fully operational at the University of Missouri Research Reactor (MURR) as well as a facility at Purdue, using special isotopes produced at MURR. High precision, fundamental Moessbauer effect studies have been carried out using Bragg scattering filters to suppress unwanted radiation. These have led to a Fourier transform method for describing Moessbauer effect (ME) lineshape and a direct method of fitting ME data to the convolution integral. These methods allow complete correction for source resonance self absorption and the accurate representation of interference effects that add an asymmetric component to the ME lines. We have begun applying these techniques to attenuated ME sources whose central peak has been attenuated by stationary resonant absorbers, to make a novel independent determination of interference parameters and line-shape behavior in the resonance asymptotic region. This analysis is important to both fundamental ME studies and to scattering studies for which a deconvolution is essential for extracting the correct recoilless fractions and interference parameters. A number of scattering studies have been successfully carried out including a study of the thermal diffuse scattering in Si, which led to an analysis of the resolution function for gamma-ray scattering. Also studied was the anharmonic motion in Na metal and the charge density wave satellite reflection Debye-Waller factor in TaS 2 , which indicate phason rather than phonon behavior. Using a specially constructed sample cell which enables us to vary temperatures from -10 C to 110 C, we have begun quasielastic diffusion studies in viscous liquids and current results are summarized. Included are the temperature and Q dependence of the scattering in pentadecane and diffusion in glycerol

  3. Perception of Breakfast Ingestion Enhances High Intensity Cycling Performance.

    Science.gov (United States)

    Mears, Stephen A; Dickinson, Kathryn; Bergin-Taylor, Kurt; Dee, Reagan; Kay, Jack; James, Lewis J

    2017-09-27

    To examine the effect on short duration, high intensity cycling time trial performance when a semi-solid breakfast containing carbohydrate or a taste and texture matched placebo is ingested 90 minutes pre-exercise compared to a water control. Thirteen well trained cyclists (25 ± 8 years, 71.1 ± 5.9 kg, 1.76 ± 0.04 m, 383 ± 46 W max , VO 2peak 4.42 ± 0.53 L·min -1 ) performed three experimental trials examining breakfast ingestion 90 minutes before a 10 minute steady state cycle (60% W max ) and a ~20 minute time trial (to complete a workload target of 376 ± 36 kJ). Subjects consumed either water (WAT), a semi-solid carbohydrate breakfast (2 g carbohydrate·kg -1 body mass; CHO) or a taste and texture matched placebo (PLA). Blood lactate and glucose concentrations were measured periodically throughout the rest and exercise periods. The time trial was completed quicker in CHO (1120 ± 69 s; P=0.006) and PLA (1112 ± 50 s; P=0.030) compared to WAT (1146 ± 74 s). Ingestion of carbohydrate caused an increase in blood glucose concentration throughout the rest period in CHO (peak at 30 minutes rest: 7.37 ± 1.10 mmol·l -1 ; Pcycling. A short duration cycling time trial was completed quicker when subjects perceived that they consumed breakfast (PLA or CHO) 90 minutes prior to the start of exercise. The improvement in performance is likely attributable to a psychological rather than physiological effect.

  4. Weight loss, dietary carbohydrate modifications, and high intensity, physical performance.

    Science.gov (United States)

    Horswill, C A; Hickner, R C; Scott, J R; Costill, D L; Gould, D

    1990-08-01

    Well trained subjects (N = 12) were studied before and after losing approximately 6% of body weight to determine whether physical performance could be maintained while consuming a hypocaloric, high percentage carbohydrate diet. During a 4-d period of weight loss, subjects were randomly assigned to a high carbohydrate (HC) or low carbohydrate (LC) diet. A crossover design was used; subjects were measured before (PRE) and after (POST) weight loss on both diets for a 6-min bout of high intensity arm cranking, weight, skinfold thickness, and profile of mood states (POMS). Hemoglobin, hematocrit, and glycerol concentrations were analyzed for resting blood samples, while lactate, pH, and base excess were analyzed for blood samples drawn at rest and 1, 3, and 5 min after arm cranking. A three-way ANOVA of sprint work revealed a weight loss effect, a diet by weight loss interaction, and an order by diet by weight loss interaction (P less than 0.05). Total sprint work (mean +/- SE) PRE and POST HC was 37.7 +/- 2.1 kJ and 37.4 +/- 2.2 kJ, respectively. Sprint work was higher for PRE LC vs POST LC, with mean values of 37.4 +/- 2.1 kJ and 34.4 +/- 2.2 kJ, respectively. Post-arm cranking lactate was significantly higher PRE compared to POST for both HC and LC. Post-exercise blood pH was lower (P less than 0.05) at PRE vs POST, with no diet effect. Regardless of the diet, POMS variables tension, depression, anger, fatigue, and confusion were significantly elevated from PRE to POST; vigor was significantly lower.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Outcomes of exertional rhabdomyolysis following high-intensity resistance training.

    Science.gov (United States)

    Huynh, A; Leong, K; Jones, N; Crump, N; Russell, D; Anderson, M; Steinfort, D; Johnson, D F

    2016-05-01

    High-intensity resistance training (HIRT) programmes are increasingly popular amongst personal trainers and those attending gymnasiums. We report the experience of exertional rhabdomyolysis (ER) at two tertiary hospitals in Melbourne, Australia. To compare the clinical outcomes of ER with other causes of rhabdomyolysis. Retrospective cross-sectional study of patients presenting with a serum creatine kinase (CK) of greater than 25 000 units/L from 1 September 2013 to 31 August 2014 at two tertiary referral hospitals in Melbourne, Australia. Records were examined to identify care measures implemented during hospital stay, clinical outcomes during admission and on subsequent follow up. Thirty four cases of rhabdomyolysis with a CK of greater than 25 000 units/L (normal range: 20-180 units/L) were identified during the 12-month study period. Twelve of the 34 cases (35%) had ER with 10 of 12 related to HIRT. No acute kidney injury, intensive care admission or death were seen among those with ER. All cases were managed conservatively, with 11 admitted and 9 receiving intravenous fluids only. In contrast, patients with rhabdomyolysis from other causes experienced significantly higher rates of intensive care admission (64%, P = 0.0002), acute kidney injury (82%, P = 0.0001) and death (27%, P = 0.069). ER resulting from HIRT appears to have a benign course compared with rhabdomyolysis of other aetiologies in patients with a serum CK greater than 25 000 units/L. Conservative management of ER appears to be adequate, although this requires confirmation in future prospective studies. © 2016 Royal Australasian College of Physicians.

  6. Boosted Higgs Shapes

    CERN Document Server

    Schlaffer, Matthias; Takeuchi, Michihisa; Weiler, Andreas; Wymant, Chris

    2014-01-01

    The inclusive Higgs production rate through gluon fusion has been measured to be in agreement with the Standard Model (SM). We show that even if the inclusive Higgs production rate is very SM-like, a precise determination of the boosted Higgs transverse momentum shape offers the opportunity to see effects of natural new physics. These measurements are generically motivated by effective field theory arguments and specifically in extensions of the SM with a natural weak scale, like composite Higgs models and natural supersymmetry. We show in detail how a measurement at high transverse momentum of $H\\to 2\\ell+\\mathbf{p}\\!\\!/_T$ via $H\\to \\tau\\tau$ and $H\\to WW^*$ could be performed and demonstrate that it offers a compelling alternative to the $t\\bar t H$ channel. We discuss the sensitivity to new physics in the most challenging scenario of an exactly SM-like inclusive Higgs cross-section.

  7. ORBIT: A code for collective beam dynamics in high-intensity rings

    International Nuclear Information System (INIS)

    Holmes, J.A.; Danilov, V.; Galambos, J.; Shishlo, A.; Cousineau, S.; Chou, W.; Michelotti, L.; Ostiguy, J.-F.; Wei, J.

    2002-01-01

    We are developing a computer code, ORBIT, specifically for beam dynamics calculations in high-intensity rings. Our approach allows detailed simulation of realistic accelerator problems. ORBIT is a particle-in-cell tracking code that transports bunches of interacting particles through a series of nodes representing elements, effects, or diagnostics that occur in the accelerator lattice. At present, ORBIT contains detailed models for strip-foil injection, including painting and foil scattering; rf focusing and acceleration; transport through various magnetic elements; longitudinal and transverse impedances; longitudinal, transverse, and three-dimensional space charge forces; collimation and limiting apertures; and the calculation of many useful diagnostic quantities. ORBIT is an object-oriented code, written in C++ and utilizing a scripting interface for the convenience of the user. Ongoing improvements include the addition of a library of accelerator maps, BEAMLINE/MXYZPTLK; the introduction of a treatment of magnet errors and fringe fields; the conversion of the scripting interface to the standard scripting language, Python; and the parallelization of the computations using MPI. The ORBIT code is an open source, powerful, and convenient tool for studying beam dynamics in high-intensity rings

  8. ORBIT: A Code for Collective Beam Dynamics in High-Intensity Rings

    Science.gov (United States)

    Holmes, J. A.; Danilov, V.; Galambos, J.; Shishlo, A.; Cousineau, S.; Chou, W.; Michelotti, L.; Ostiguy, J.-F.; Wei, J.

    2002-12-01

    We are developing a computer code, ORBIT, specifically for beam dynamics calculations in high-intensity rings. Our approach allows detailed simulation of realistic accelerator problems. ORBIT is a particle-in-cell tracking code that transports bunches of interacting particles through a series of nodes representing elements, effects, or diagnostics that occur in the accelerator lattice. At present, ORBIT contains detailed models for strip-foil injection, including painting and foil scattering; rf focusing and acceleration; transport through various magnetic elements; longitudinal and transverse impedances; longitudinal, transverse, and three-dimensional space charge forces; collimation and limiting apertures; and the calculation of many useful diagnostic quantities. ORBIT is an object-oriented code, written in C++ and utilizing a scripting interface for the convenience of the user. Ongoing improvements include the addition of a library of accelerator maps, BEAMLINE/MXYZPTLK; the introduction of a treatment of magnet errors and fringe fields; the conversion of the scripting interface to the standard scripting language, Python; and the parallelization of the computations using MPI. The ORBIT code is an open source, powerful, and convenient tool for studying beam dynamics in high-intensity rings.

  9. ORBIT: A CODE FOR COLLECTIVE BEAM DYNAMICS IN HIGH INTENSITY RINGS

    International Nuclear Information System (INIS)

    HOLMES, J.A.; DANILOV, V.; GALAMBOS, J.; SHISHLO, A.; COUSINEAU, S.; CHOU, W.; MICHELOTTI, L.; OSTIGUY, J.F.; WEI, J.

    2002-01-01

    We are developing a computer code, ORBIT, specifically for beam dynamics calculations in high-intensity rings. Our approach allows detailed simulation of realistic accelerator problems. ORBIT is a particle-in-cell tracking code that transports bunches of interacting particles through a series of nodes representing elements, effects, or diagnostics that occur in the accelerator lattice. At present, ORBIT contains detailed models for strip-foil injection, including painting and foil scattering; rf focusing and acceleration; transport through various magnetic elements; longitudinal and transverse impedances; longitudinal, transverse, and three-dimensional space charge forces; collimation and limiting apertures; and the calculation of many useful diagnostic quantities. ORBIT is an object-oriented code, written in C++ and utilizing a scripting interface for the convenience of the user. Ongoing improvements include the addition of a library of accelerator maps, BEAMLINE/MXYZPTLK, the introduction of a treatment of magnet errors and fringe fields; the conversion of the scripting interface to the standard scripting language, Python; and the parallelization of the computations using MPI. The ORBIT code is an open source, powerful, and convenient tool for studying beam dynamics in high-intensity rings

  10. High-intensity interval exercise training for public health: a big HIT or shall we HIT it on the head?

    Science.gov (United States)

    Biddle, Stuart J H; Batterham, Alan M

    2015-07-18

    The efficacy of high-intensity interval training for a broad spectrum of cardio-metabolic health outcomes is not in question. Rather, the effectiveness of this form of exercise is at stake. In this paper we debate the issues concerning the likely success or failure of high-intensity interval training interventions for population-level health promotion. Biddle maintains that high-intensity interval training cannot be a viable public health strategy as it will not be adopted or maintained by many people. This conclusion is based on an analysis of perceptions of competence, the psychologically aversive nature of high-intensity exercise, the affective component of attitudes, the less conscious elements of motivated behaviour that reflect our likes and dislikes, and analysis using the RE-AIM framework. Batterham argues that this appraisal is based on a constrained and outmoded definition of high-intensity interval training and that truly practical and scalable protocols have been - and continue to be - developed. He contends that the purported displeasure associated with this type of exercise has been overstated. Biddle suggests that the way forward is to help the least active become more active rather than the already active to do more. Batterham claims that traditional physical activity promotion has been a spectacular failure. He proposes that, within an evolutionary health promotion framework, high-intensity interval training could be a successful population strategy for producing rapid physiological adaptations benefiting public health, independent of changes in total physical activity energy expenditure. Biddle recommends that we focus our attention elsewhere if we want population-level gains in physical activity impacting public health. His conclusion is based on his belief that high-intensity interval training interventions will have limited reach, effectiveness, and adoption, and poor implementation and maintenance. In contrast, Batterham maintains that there

  11. Physiological changes during low- and high-intensity noninvasive ventilation.

    Science.gov (United States)

    Lukácsovits, J; Carlucci, A; Hill, N; Ceriana, P; Pisani, L; Schreiber, A; Pierucci, P; Losonczy, G; Nava, S

    2012-04-01

    In a physiological randomised cross-over study performed in stable hypercapnic chronic obstructive disease patients, we assessed the short-term effects of two settings of noninvasive ventilation. One setting was aimed at maximally reducing arterial carbon dioxide tension (P(a,CO(2))) (high-intensity (Hi) noninvasive positive pressure ventilation (NPPV)): mean ± SD 27.6 ± 2.1 cmH(2)O of inspiratory positive airway pressure, 4 ± 0 cmH(2)O of expiratory positive airway pressure and respiratory rate of 22 breaths · min(-1). The other was performed according to the usual parameters used in earlier studies (low-intensity (Li)-NPPV): 17.7 ± 1.6 cmH(2)O of inspiratory positive airway pressure, 4 ± 0 cmH(2)O of expiratory positive airway pressure and respiratory rate of 12 breaths · min(-1). Both modes of ventilation significantly improved gas exchange compared with spontaneous breathing (SB), but to a greater extent using Hi-NPPV (P(a,CO(2)) 59.3 ± 7.5, 55.2 ± 6.9 and 49.4 ± 7.8 mmHg for SB, Li-NPPV and Hi-NPPV, respectively). Similarly, Hi-NPPV induced a greater reduction in the pressure-time product of the diaphragm per minute from 323 ± 149 cmH(2)O · s · min(-1) during SB to 132 ± 139 cmH(2)O · s · min(-1) during Li-NPPV and 40 ± 69 cmH(2)O · s · min(-1) during Hi-NPPV, while in nine out of 15 patients, it completely abolished SB activity. Hi-NPPV also induced a marked reduction in cardiac output (CO) measured noninvasively with a Finometer PRO (Finapres Medical Systems BV, Amsterdam, the Netherlands) compared with Li-NPPV. We conclude that while Hi-NPPV is more effective than Li-NPPV in improving gas exchange and in reducing inspiratory effort, it induces a marked reduction in CO, which needs to be considered when Hi-NPPV is applied to patients with pre-existing cardiac disease.

  12. Advanced approaches to high intensity laser-driven ion acceleration

    International Nuclear Information System (INIS)

    Henig, Andreas

    2010-01-01

    Since the pioneering work that was carried out 10 years ago, the generation of highly energetic ion beams from laser-plasma interactions has been investigated in much detail in the regime of target normal sheath acceleration (TNSA). Creation of ion beams with small longitudinal and transverse emittance and energies extending up to tens of MeV fueled visions of compact, laser-driven ion sources for applications such as ion beam therapy of tumors or fast ignition inertial con finement fusion. However, new pathways are of crucial importance to push the current limits of laser-generated ion beams further towards parameters necessary for those applications. The presented PhD work was intended to develop and explore advanced approaches to high intensity laser-driven ion acceleration that reach beyond TNSA. In this spirit, ion acceleration from two novel target systems was investigated, namely mass-limited microspheres and nm-thin, free-standing diamond-like carbon (DLC) foils. Using such ultrathin foils, a new regime of ion acceleration was found where the laser transfers energy to all electrons located within the focal volume. While for TNSA the accelerating electric field is stationary and ion acceleration is spatially separated from laser absorption into electrons, now a localized longitudinal field enhancement is present that co-propagates with the ions as the accompanying laser pulse pushes the electrons forward. Unprecedented maximum ion energies were obtained, reaching beyond 0.5 GeV for carbon C 6+ and thus exceeding previous TNSA results by about one order of magnitude. When changing the laser polarization to circular, electron heating and expansion were shown to be efficiently suppressed, resulting for the first time in a phase-stable acceleration that is dominated by the laser radiation pressure which led to the observation of a peaked C 6+ spectrum. Compared to quasi-monoenergetic ion beam generation within the TNSA regime, a more than 40 times increase in

  13. Advanced approaches to high intensity laser-driven ion acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Henig, Andreas

    2010-04-26

    Since the pioneering work that was carried out 10 years ago, the generation of highly energetic ion beams from laser-plasma interactions has been investigated in much detail in the regime of target normal sheath acceleration (TNSA). Creation of ion beams with small longitudinal and transverse emittance and energies extending up to tens of MeV fueled visions of compact, laser-driven ion sources for applications such as ion beam therapy of tumors or fast ignition inertial con finement fusion. However, new pathways are of crucial importance to push the current limits of laser-generated ion beams further towards parameters necessary for those applications. The presented PhD work was intended to develop and explore advanced approaches to high intensity laser-driven ion acceleration that reach beyond TNSA. In this spirit, ion acceleration from two novel target systems was investigated, namely mass-limited microspheres and nm-thin, free-standing diamond-like carbon (DLC) foils. Using such ultrathin foils, a new regime of ion acceleration was found where the laser transfers energy to all electrons located within the focal volume. While for TNSA the accelerating electric field is stationary and ion acceleration is spatially separated from laser absorption into electrons, now a localized longitudinal field enhancement is present that co-propagates with the ions as the accompanying laser pulse pushes the electrons forward. Unprecedented maximum ion energies were obtained, reaching beyond 0.5 GeV for carbon C{sup 6+} and thus exceeding previous TNSA results by about one order of magnitude. When changing the laser polarization to circular, electron heating and expansion were shown to be efficiently suppressed, resulting for the first time in a phase-stable acceleration that is dominated by the laser radiation pressure which led to the observation of a peaked C{sup 6+} spectrum. Compared to quasi-monoenergetic ion beam generation within the TNSA regime, a more than 40 times

  14. Radiative properties of ceramic metal-halide high intensity discharge lamps containing additives in argon plasma

    Science.gov (United States)

    Cressault, Yann; Teulet, Philippe; Zissis, Georges

    2016-07-01

    The lighting represents a consumption of about 19% of the world electricity production. We are thus searching new effective and environment-friendlier light sources. The ceramic metal-halide high intensity lamps (C-MHL) are one of the options for illuminating very high area. The new C-MHL lamps contain additives species that reduce mercury inside and lead to a richer spectrum in specific spectral intervals, a better colour temperature or colour rendering index. This work is particularly focused on the power radiated by these lamps, estimated using the net emission coefficient, and depending on several additives (calcium, sodium, tungsten, dysprosium, and thallium or strontium iodides). The results show the strong influence of the additives on the power radiated despite of their small quantity in the mixtures and the increase of visible radiation portion in presence of dysprosium.

  15. Benchmark of Space Charge Simulations and Comparison with Experimental Results for High Intensity, Low Energy Accelerators

    CERN Document Server

    Cousineau, Sarah M

    2005-01-01

    Space charge effects are a major contributor to beam halo and emittance growth leading to beam loss in high intensity, low energy accelerators. As future accelerators strive towards unprecedented levels of beam intensity and beam loss control, a more comprehensive understanding of space charge effects is required. A wealth of simulation tools have been developed for modeling beams in linacs and rings, and with the growing availability of high-speed computing systems, computationally expensive problems that were inconceivable a decade ago are now being handled with relative ease. This has opened the field for realistic simulations of space charge effects, including detailed benchmarks with experimental data. A great deal of effort is being focused in this direction, and several recent benchmark studies have produced remarkably successful results. This paper reviews the achievements in space charge benchmarking in the last few years, and discusses the challenges that remain.

  16. Optical Frequency Optimization of a High Intensity Laser Power Beaming System Utilizing VMJ Photovoltaic Cells

    Science.gov (United States)

    Raible, Daniel E.; Dinca, Dragos; Nayfeh, Taysir H.

    2012-01-01

    An effective form of wireless power transmission (WPT) has been developed to enable extended mission durations, increased coverage and added capabilities for both space and terrestrial applications that may benefit from optically delivered electrical energy. The high intensity laser power beaming (HILPB) system enables long range optical 'refueling" of electric platforms such as micro unmanned aerial vehicles (MUAV), airships, robotic exploration missions and spacecraft platforms. To further advance the HILPB technology, the focus of this investigation is to determine the optimal laser wavelength to be used with the HILPB receiver, which utilizes vertical multi-junction (VMJ) photovoltaic cells. Frequency optimization of the laser system is necessary in order to maximize the conversion efficiency at continuous high intensities, and thus increase the delivered power density of the HILPB system. Initial spectral characterizations of the device performed at the NASA Glenn Research Center (GRC) indicate the approximate range of peak optical-to-electrical conversion efficiencies, but these data sets represent transient conditions under lower levels of illumination. Extending these results to high levels of steady state illumination, with attention given to the compatibility of available commercial off-the-shelf semiconductor laser sources and atmospheric transmission constraints is the primary focus of this paper. Experimental hardware results utilizing high power continuous wave (CW) semiconductor lasers at four different operational frequencies near the indicated band gap of the photovoltaic VMJ cells are presented and discussed. In addition, the highest receiver power density achieved to date is demonstrated using a single photovoltaic VMJ cell, which provided an exceptionally high electrical output of 13.6 W/sq cm at an optical-to-electrical conversion efficiency of 24 percent. These results are very promising and scalable, as a potential 1.0 sq m HILPB receiver of

  17. AveBoost2: Boosting for Noisy Data

    Science.gov (United States)

    Oza, Nikunj C.

    2004-01-01

    AdaBoost is a well-known ensemble learning algorithm that constructs its constituent or base models in sequence. A key step in AdaBoost is constructing a distribution over the training examples to create each base model. This distribution, represented as a vector, is constructed to be orthogonal to the vector of mistakes made by the pre- vious base model in the sequence. The idea is to make the next base model's errors uncorrelated with those of the previous model. In previous work, we developed an algorithm, AveBoost, that constructed distributions orthogonal to the mistake vectors of all the previous models, and then averaged them to create the next base model s distribution. Our experiments demonstrated the superior accuracy of our approach. In this paper, we slightly revise our algorithm to allow us to obtain non-trivial theoretical results: bounds on the training error and generalization error (difference between training and test error). Our averaging process has a regularizing effect which, as expected, leads us to a worse training error bound for our algorithm than for AdaBoost but a superior generalization error bound. For this paper, we experimented with the data that we used in both as originally supplied and with added label noise-a small fraction of the data has its original label changed. Noisy data are notoriously difficult for AdaBoost to learn. Our algorithm's performance improvement over AdaBoost is even greater on the noisy data than the original data.

  18. The effect of progressive high-intensity inspiratory muscle training and fixed high-intensity inspiratory muscle training on the asymmetry of diaphragm thickness in stroke patients.

    Science.gov (United States)

    Jung, Ju-Hyeon; Kim, Nan-Soo

    2015-10-01

    [Purpose] This study investigated the effects of progressive load and fixed load high-intensity inspiratory muscle training on the asymmetry of diaphragm thickness in stroke patients. [Subjects] Twenty-one stroke patients were assigned to one of three groups: progressive load high-intensity inspiratory muscle training (n = 8), fixed load high-intensity inspiratory muscle training (n = 6), and controls (n = 7). [Methods] The progressive load and fixed load high-intensity inspiratory muscle training participants undertook an exercise program for 20 minutes, three times weekly, for 6 weeks. After each session, diaphragm thickness was measured using ultrasonography. The diaphragm asymmetry ratio and diaphragm thickening ratio were standardized using a formula. [Results] After intervention, the diaphragm asymmetry ratio significantly differed among the three groups, and the diaphragm asymmetry ratio significantly increased in the control group. A significant increase was identified in the diaphragm thickening ratio within the progressive load and fixed load high-intensity inspiratory muscle training groups. [Conclusion] Progressive load and fixed load high-intensity inspiratory muscle training decreased the asymmetry of diaphragm thickness in stroke patients; this effect, in turn, increased the diaphragm thickening ratio in stroke patients. The two interventions examined here should be selectively applied to individuals in the clinical field.

  19. Handling of high intensity proton beams at 12 GeV

    International Nuclear Information System (INIS)

    Takasaki, M.; Minakawa, M.; Yamanoi, Y.; Ieiri, M.; Kato, Y.; Ishii, H.; Suzuki, Y.; Suzuki, T.; Tanaka, K.H.

    1990-01-01

    A new counter experimental hall is now being constructed at the KEK (National Laboratory for High Energy Physics, Japan) 12 GeV Proton Synchrotron (KEK-PS). This hall will be completed by the end of 1989, immediately followed by magnet installation. The present report describes the new technical achievements employed at the hall. The most important and essential feature of the equipment is that the beam-handling system is maintenance-free, though in case of need, maintenance should be carried out quickly from a distant location in order to reduce the absorbed dose during the maintenance work. This paper is divided into three parts. The first part outlines the general design concept of the hall, focusing on the handling of high-intensity beams. The second part addresses the development of a quick-disconnect system, focusing on electric power, interlock signals, cooling water, pumping port, and vacuum flange. The third part describes the development of radiation-resistant instruments, focusing on polyimide magnets and cement magnets. (N.K.)

  20. High intensity proton linac activities at Los Alamos

    International Nuclear Information System (INIS)

    Rusnak, B.; Chan, K.C.; Campbell, B.

    1998-01-01

    High-current proton linear accelerators offer an attractive alternative for generating the intense neutron fluxes needed for transmutations technologies, tritium production and neutron science. To achieve the fluxes required for tritium production, a 100-mA, 1700-MeV cw proton accelerator is being designed that uses superconducting cavities for the high-energy portion of the linac, from 211 to 1,700 MeV. The development work supporting the linac design effort is focused on three areas: superconducting cavity performance for medium-beta cavities at 700 MHz, high power rf coupler development, and cryomodule design. An overview of the progress in these three areas is presented

  1. Focal construct geometry for high intensity energy dispersive x-ray diffraction based on x-ray capillary optics

    Energy Technology Data Exchange (ETDEWEB)

    Li, Fangzuo; Liu, Zhiguo; Sun, Tianxi, E-mail: stx@bnu.edu.cn; Jiang, Bowen; Zhu, Yu [The Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China)

    2016-03-14

    We presented a focal construct geometry (FCG) method for high intensity energy dispersive X-ray diffraction by utilizing a home-made ellipsoidal single-bounce capillary (ESBC) and a polycapillary parallel X-ray lens (PPXRL). The ESBC was employed to focus the X-rays from a conventional laboratory source into a small focal spot and to produce an annular X-ray beam in the far-field. Additionally, diffracted polychromatic X-rays were confocally collected by the PPXRL attached to a stationary energy-resolved detector. Our FCG method based on ESBC and PPXRL had achieved relatively high intensity diffraction peaks and effectively narrowed the diffraction peak width which was helpful in improving the potential d-spacing resolution for material phase analysis.

  2. High-intensity light-ion beam research at NRL

    International Nuclear Information System (INIS)

    Cooperstein, G.; Colombant, D.G.; Barker, R.J.

    1982-01-01

    High-brightness proton beams (.4 MA, 1 MV) have recently been extracted from 20 cm 2 axial pinch-reflex diodes (PRDs) mounted on the NRL Gamble II generator. A source power brightness of GT 10 TW/cm 2 rad 2 was achieved in these experiments. A new barrel-shaped equitorial PRD that can be coupled to PBFA-II has also been operated on Gamble II and has demonstrated 50% proton efficiency with predominately azimuthally-symmetric charged-particle flow. In other experiments the stopping power of deuterons in hot plasmas was measured using a PRD on Gamble II. Results show about 40% enhancement in stopping power over that in cold targets when the beam was focused to about .25 MA/cm 2 . Research is also being performed on transporting ion beams in large-diameter channels (>= 2.5 cm) and on a post-transport, plasma-filled, magnetic-focusing section to bring the beam to pellet dimensions. (author)

  3. High-intensity pulsed beam source with tunable operation mode

    Science.gov (United States)

    Nashilevskiy, A. V.; Kanaev, G. G.; Ezhov, V. V.; Shamanin, V. I.

    2017-05-01

    The report presents the design of an electron and an ion pulsed accelerator. The powerful high-voltage pulse generator of the accelerator and the vacuum bushing insulator is able to change the polarity of the output voltage. The low-inductance matching transformer provides an increase in the DFL output impedance by 4 times. The generator based on a high voltage pulse transformer and a pseudo spark switch is applied for DFL charging. The high-impedance magnetically insulated focusing diode with Br magnetic field and the “passive” anode was used to realize the ion beam generation mode. The plasma is formed on the surface of the anode caused by an electrical breakdown at the voltage edge pulse; as a result, the carbon ion and proton beam is generated. This beam has the following parameters: the current density is about 400 A/cm2 (in focus): the applied voltage is up to 450 kV. The accelerator is designed for the research on the interaction of the charged particle pulsed beams with materials and for the development of technological processes of a material modification.

  4. High-intensity laser diagnostics for OMEGA EP

    International Nuclear Information System (INIS)

    Bromage, J.; Zuegel, J.D.; Bahk, S.W.; Vickery, D.S.; Waxer, L.J.; Irwin, D.; Bagnoud, V.; Boni, R.; Moore, M.D.; Jungquist, R.; Stoeckl, C.

    2006-01-01

    OMEGA EP (Extended Performance) is a new high-energy peta-watt laser system under construction at the University of Rochester's Laboratory for Laser Energetics. This paper describes our designs for two diagnostics critical to OMEGA EP's mission. The focal-spot diagnostic (FSD) is responsible for characterizing the focal spot of OMEGA EP's off-axis parabolic mirror at full energy. The ultrafast temporal diagnostic (UTD) is responsible for characterizing pulse shapes of full-energy target shots ranging in width from < 1 to 100 ps as well as setting the desired pulse width before the shot. These diagnostics will enable, for the first time, complete spatial and temporal characterization of the focus of a high-energy peta-watt laser at full energy. (authors)

  5. High-Intensity Plasma Glass Melter Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Gonterman, J. Ronald; Weinstein, Michael A.

    2006-10-27

    The purpose of this project was to demonstrate the energy efficiency and reduced emissions that can be obtained with a dual torch DC plasma transferred arc-melting system. Plasmelt Glass Technologies, LLC was formed to solicit and execute the project, which utilize a full-scale test melter system. The system is similar to the one that was originally constructed by Johns Manville, but Plasmelt has added significant improvements to the torch design and melter system that has extended the original JM short torch lives. The original JM design has been shown to achieve melt rates 5 to 10 times faster than conventional gas or electric melting, with improved energy efficiency and reduced emissions. This project began on 7/28/2003 and ended 7/27/06. A laboratory scale melter was designed, constructed, and operated to conduct multiple experimental melting trials on various glass compositions. Glass quality was assessed. Although the melter design is generic and equally applicable to all sectors within the glass industry, the development of this melter has focused primarily on fiberglass with additional exploratory melting trials of frits, specialty, and minerals-melting applications. Throughput, energy efficiency, and glass quality have been shown to be heavily dependent on the selected glass composition. During this project, Plasmelt completed the proof-of-concept work in our Boulder, CO Lab to show the technical feasibility of this transferred-arc plasma melter. Late in the project, the work was focused on developing the processes and evaluating the economic viability of plasma melting aimed at the specific glasses of interest to specific client companies. Post project work is on going with client companies to address broader non-glass materials such as refractories and industrial minerals. Exploratory melting trials have been conducted on several glasses of commercial interest including: C-glass, E-glass, S-Glass, AR-Glass, B-glass, Lighting Glass, NE-Glass, and various

  6. Interaction of High Intensity Electromagnetic Waves with Plasmas: Final Report

    International Nuclear Information System (INIS)

    Shvets, G.

    2008-01-01

    The focus of our work during the duration of this grant was on the following areas: (a) the fundamental plasma physics of intense laser-plasma interactions, including the nonlinear excitation of plasma waves for accelerator applications, as well as the recently discovered by us phenomenon of the relativistic bi-stability of relativistic plasma waves driven by a laser beatwave; (b) interaction of high power microwave beams with magnetized plasma, including some of the recently discovered by us phenomena such as the Undulator Induced Transparency (UIT) as well as the new approaches to dynamic manipulation of microwave pulses; (c) investigations of the multi-color laser pulse interactions in the plasma, including the recently discovered by us phenomenon of Electromagnetic Cascading (EC) and the effect of the EC of three-dimensional dynamics of laser pulses (enhanced/suppressed selffocusing etc.); (d) interaction of high-current electron beams with the ambient plasma in the context of Fast Ignitor (FI) physics, with the emphasis on the nonlinear dynamics of the Weibel instability and beam filamentation.

  7. 21 CFR 1040.30 - High-intensity mercury vapor discharge lamps.

    Science.gov (United States)

    2010-04-01

    ... advertisement. Advertising for any high-intensity mercury vapor discharge lamp that does not comply with... mercury and that is contained within an outer envelope. (2) Advertisement means any catalog, specification... 21 Food and Drugs 8 2010-04-01 2010-04-01 false High-intensity mercury vapor discharge lamps. 1040...

  8. High-intensity training reduces CD8+ T-cell redistribution in response to exercise

    NARCIS (Netherlands)

    Witard, O.C.; Turner, J.E.; Jackman, S.R.; Tipton, K.D.; Jeukendrup, A.E.; Kies, A.K.; Bosch, J.A.

    2012-01-01

    Purpose: We examined whether exercise-induced lymphocytosis and lymphocytopenia are impaired with high-intensity training. Methods: Eight trained cyclists (V·O2max = 64.2 ± 6.5 mL·kg-1·min-1) undertook 1 wk of normal-intensity training and a second week of high-intensity training. On day 7 of each

  9. The influence of basketball dribbling on repeated high-intensity intermittent runs

    Directory of Open Access Journals (Sweden)

    Zhaowei Kong

    2015-12-01

    Conclusion: The results suggest that the Yo-Yo IE2 test could reflect the repeatability of high-intensity intermittent basketball dribbling performance, while dribbling skills may have different influences on high-intensity intermittent exercise capacity in adolescent players at different ages.

  10. Underutilization of high-intensity statin therapy after hospitalization for coronary heart disease.

    Science.gov (United States)

    Rosenson, Robert S; Kent, Shia T; Brown, Todd M; Farkouh, Michael E; Levitan, Emily B; Yun, Huifeng; Sharma, Pradeep; Safford, Monika M; Kilgore, Meredith; Muntner, Paul; Bittner, Vera

    2015-01-27

    National guidelines recommend use of high-intensity statins after hospitalization for coronary heart disease (CHD) events. This study sought to estimate the proportion of Medicare beneficiaries filling prescriptions for high-intensity statins after hospital discharge for a CHD event and to analyze whether statin intensity before hospitalization is associated with statin intensity after discharge. We conducted a retrospective cohort study using a 5% random sample of Medicare beneficiaries between 65 and 74 years old. Beneficiaries were included in the analysis if they filled a statin prescription after a CHD event (myocardial infarction or coronary revascularization) in 2007, 2008, or 2009. High-intensity statins included atorvastatin 40 to 80 mg, rosuvastatin 20 to 40 mg, and simvastatin 80 mg. Among 8,762 Medicare beneficiaries filling a statin prescription after a CHD event, 27% of first post-discharge fills were for a high-intensity statin. The percent filling a high-intensity statin post-discharge was 23.1%, 9.4%, and 80.7%, for beneficiaries not taking statins pre-hospitalization, taking low/moderate-intensity statins, and taking high-intensity statins before their CHD event, respectively. Compared with beneficiaries not on statin therapy pre-hospitalization, multivariable adjusted risk ratios for filling a high-intensity statin were 4.01 (3.58-4.49) and 0.45 (0.40-0.52) for participants taking high-intensity and low/moderate-intensity statins before their CHD event, respectively. Only 11.5% of beneficiaries whose first post-discharge statin fill was for a low/moderate-intensity statin filled a high-intensity statin within 365 days of discharge. The majority of Medicare beneficiaries do not fill high-intensity statins after hospitalization for CHD. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  11. Topological Design and Modulation Strategy for Buck-Boost Three-Level Inverters

    DEFF Research Database (Denmark)

    Gao, Feng; Loh, Poh Chiang; Teodorescu, Remus

    2009-01-01

    To date, designed topologies for dc-ac inversion with both voltage buck and boost capabilities are mainly focused on two-level circuitries with extensions to three-level possibilities left nearly unexplored. Contributing to this area of research, this paper presents the design of a number of viable...... can perform distinct five-level line voltage and three-level phase voltage switching by simply controlling the active switches located in the designed voltage boost section of the circuits. As a cost saving option, one active switch can further be removed from the voltage boost section of the circuits...... buck-boost threelevel inverters that can also support bidirectional power conversion. The proposed front-end circuitry is developed from the C´ ukderived buck-boost two-level inverter, and by using the "alternative phase opposition disposition" modulation scheme, the buck-boost three-level inverters...

  12. Boost.Asio C++ network programming

    CERN Document Server

    Torjo, John

    2013-01-01

    What you want is an easy level of abstraction, which is just what this book provides in conjunction with Boost.Asio. Switching to Boost.Asio is just a few extra #include directives away, with the help of this practical and engaging guide.This book is great for developers that need to do network programming, who don't want to delve into the complicated issues of a raw networking API. You should be familiar with core Boost concepts, such as smart pointers and shared_from_this, resource classes (noncopyable), functors and boost::bind, boost mutexes, and the boost date/time library. Readers should

  13. Short-term effects of implemented high intensity shoulder elevation during computer work

    Directory of Open Access Journals (Sweden)

    Madeleine Pascal

    2009-08-01

    Full Text Available Abstract Background Work-site strength training sessions are shown effective to prevent and reduce neck-shoulder pain in computer workers, but difficult to integrate in normal working routines. A solution for avoiding neck-shoulder pain during computer work may be to implement high intensity voluntary contractions during the computer work. However, it is unknown how this may influence productivity, rate of perceived exertion (RPE as well as activity and rest of neck-shoulder muscles during computer work. The aim of this study was to investigate short-term effects of a high intensity contraction on productivity, RPE and upper trapezius activity and rest during computer work and a subsequent pause from computer work. Methods 18 female computer workers performed 2 sessions of 15 min standardized computer mouse work preceded by 1 min pause with and without prior high intensity contraction of shoulder elevation. RPE was reported, productivity (drawings per min measured, and bipolar surface electromyography (EMG recorded from the dominant upper trapezius during pauses and sessions of computer work. Repeated measure ANOVA with Bonferroni corrected post-hoc tests was applied for the statistical analyses. Results The main findings were that a high intensity shoulder elevation did not modify RPE, productivity or EMG activity of the upper trapezius during the subsequent pause and computer work. However, the high intensity contraction reduced the relative rest time of the uppermost (clavicular trapezius part during the subsequent pause from computer work (p Conclusion Since a preceding high intensity shoulder elevation did not impose a negative impact on perceived effort, productivity or upper trapezius activity during computer work, implementation of high intensity contraction during computer work to prevent neck-shoulder pain may be possible without affecting the working routines. However, the unexpected reduction in clavicular trapezius rest during a

  14. Q-Boosted Optomechanical Resonators

    Science.gov (United States)

    2015-11-18

    proposing team in 2004 [6], and apparently copied now by some in the optomechanical world, who seem to be calling it a spoke-supported toroid . Beyond merely...FA9550-10-1-0293 “Q-Boosted Optomechanical Resonators” CTN 9/18/15 24 [20] D. Armani, T. Kippenberg, S. Spillane and K. Vahala, "Ultra-high-Q toroid

  15. BIM-Boost in Nederland

    NARCIS (Netherlands)

    Berlo, L.A.H.M.

    2012-01-01

    Onlangs sloot TNO een samenwerkingsovereenkomst met brancheorganisaties in de bouwkolom waaromder Bouwend Nederland en BNA. Doel van de overeenkomst: een BIM-boost in Nederland bewerkstelligen. Een gesprek met Leon van Berlo van TNO over deze en andere BIM-actualiteiten

  16. High-intensity intermittent swimming improves cardiovascular health status for women with mild hypertension

    DEFF Research Database (Denmark)

    Mohr, Magni; Nordsborg, Nikolai Baastrup; Lindenskov, Annika

    2014-01-01

    To test the hypothesis that high-intensity swim training improves cardiovascular health status in sedentary premenopausal women with mild hypertension, sixty-two women were randomized into high-intensity (n = 21; HIT), moderate-intensity (n = 21; MOD), and control groups (n = 20; CON). HIT...... training strategy to improve cardiovascular health and physical performance...... in sedentary women with mild hypertension. Adaptations are similar with high- and moderate-intensity training, despite markedly less total time spent and distance covered in the high-intensity group....

  17. Effects of High-Intensity Interval Training versus Continuous Training on Physical Fitness, Cardiovascular Function and Quality of Life in Heart Failure Patients.

    NARCIS (Netherlands)

    Benda, N.M.M.; Seeger, J.P.; Stevens, G.G.; Hijmans-Kersten, B.T.P.; Dijk, A.P.J. van; Bellersen, L.; Lamfers, E.J.; Hopman, M.T.E.; Thijssen, D.H.J.

    2015-01-01

    INTRODUCTION: Physical fitness is an important prognostic factor in heart failure (HF). To improve fitness, different types of exercise have been explored, with recent focus on high-intensity interval training (HIT). We comprehensively compared effects of HIT versus continuous training (CT) in HF

  18. Effects of strength training on muscle fiber types and size; consequences for athletes training for high-intensity sport

    DEFF Research Database (Denmark)

    Andersen, J L; Aagaard, P

    2010-01-01

    of the muscle and finally how will this affect the performance of the athlete. In addition, the review will deal with muscle hypertrophy and how it develops with strength training. Overall, it is not the purpose of this review to give a comprehensive up-date of the area, but to pin-point a few issues from which...... way into almost all sports in which high intense work is conducted. In this review we will focus on a few selected aspects and consequences of strength training; namely what effects do strength training have of muscle fiber type composition, and how may these effects change the contractile properties...

  19. Radiative properties of Ceramic Metal-Halide High Intensity Discharge lamps (CMH) containing additives in argon plasma

    Science.gov (United States)

    Cressault, Yann; Teulet, Philippe; Zissis, Georges; Laplace Team

    2015-09-01

    The lighting represents a consumption of about 19% of the world electricity production. We are thus searching new effective and environment-friendlier light sources. The Ceramic Metal-Halide High Intensity Lamps (CMH) are one of the options for illuminating very high area. The new CMH lamps are mercury free and contain additives species which lead to a richer spectrum in specific spectral intervals, a better colour temperature or colour rendering index. This work is particularly focused on the power radiated by these lamps, estimated using the Net Emission Coefficient, and depending on several additives (calcium, sodium, tungsten, dysprosium, thallium or strontium).

  20. Effects of strength training on muscle fiber types and size; consequences for athletes training for high-intensity sport

    DEFF Research Database (Denmark)

    Andersen, J L; Aagaard, P

    2010-01-01

    way into almost all sports in which high intense work is conducted. In this review we will focus on a few selected aspects and consequences of strength training; namely what effects do strength training have of muscle fiber type composition, and how may these effects change the contractile properties...... functional training advises can be made. Thus, more than a review in the traditional context this review should be viewed upon as an attempt to bring sports-physiologists and coaches or others working directly with the athletes together for a mutual discussion on how recently acquired physiological knowledge...

  1. A conceptual design of the DTL-SDTL for the JAERI high intensity proton accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Ino, Hiroshi; Kabeya, Zenzaburo [Mitsubishi Heavy Industries Ltd., Tokyo (Japan); Chishiro, Etsuji; Ouchi, Nobuo; Hasegawa, Kazuo; Mizumoto, Motoharu

    1998-08-01

    A high intensity proton linear accelerator with an energy of 1.5 GeV and an average beam power of 8 MW has been proposed for the Neutron Science Project (NSP) at JAERI. This linac starts with radio-frequency quadrupole (RFQ) linac, which is followed by a drift-tube linac (DTL), separated-type DTL (SDTL), and a superconducting structure. In this report, we focus on the DTL and SDTL part of the accelerator. The DTL accelerates the beam from 2 to 51 MeV, and SDTL accelerates the beam from 51 to 10 MeV. Since the main features of the requirement for the DTL-SDTL are high peak current ({approx}30 mA) and a high-duty factor ({approx}CW), the conceptual design should be determined not only based on the result of a beam-dynamics calculation, but by careful study of the cooling problems. The design processes of the DTL-SDTL and the matching sections (RFQ to DTL, CW-Pulse merge section, and SDTL to SCC) and the result of a heat transfer analysis of DTL are described. (author)

  2. Time Integrated Soft X-ray Imaging in High Intensity Laser Experiments (thesis)

    Energy Technology Data Exchange (ETDEWEB)

    Stafford, David [Univ. of California, Davis, CA (United States)

    2009-01-01

    2009 marks a significant achievement and the dawn of a new era in high intensity laser research with the final commissioning of all 192 beams at the National Ignition Facility (NIF). NIF is a department of energy (DOE) funded project more than 10 years in the making located at the Lawrence Livermore National Laboratory (LLNL). The following research was done as one of many preliminary experiments done to prepare for these historic events. The primary focus of the experimental campaign this paper addresses is to test and develop a thermal x-radiation source using a short pulse laser. This data is hoped to provide information about the thermal transport mechanisms important in the development of prediction models in High Energy Density (HED) science. One of several diagnostics fielded was a soft x-ray imager (SXRI) which is detailed in this paper. The SXRI will be used to measure the relative size of the heated region and also the relative level of specific x-ray emissions among several shot and target configurations. The laser system used was the Titan laser located in the Jupiter Laser Facility (JLF) at Lawrence Livermore National Laboratory (LLNL). Titan uses the JLF Janus Nd:glass laser west frontend system with a Optical Parametric Chirped Pulse Amplification (OPCPA) in place of the nanosecond oscillator. The system is capable of producing laser intensities of over a petawatt with several tens of joules delivered in the beam.

  3. Proton probing of ultra-thin foil dynamics in high intensity regime

    Science.gov (United States)

    Prasad, Rajendra; Aktan, Esin; Aurand, Bastian; Cerchez, Mirela; Willi, Oswald

    2017-10-01

    The field of laser driven ion acceleration has been enriched significantly over the past decade, thanks to the advanced laser technologies. Already, from 100s TW class systems, laser driven sources of particles and radiations are being considered in number of potential applications in science and medicine due to their unique properties. New physical effects unearthed at these systems may help understand and conduct successful experiments at several PW class multi-beam facilities with high rep rate systems, e.g. ELI. Here we present the first experimental results on ultra-thin foil dynamics irradiated by an ultra-high intensity (1020 W/cm2) , ultra-high contrast (10-12) laser pulse at ARCTURUS laser facility at HHU Duesseldorf. By employing the elegant proton probing technique it is observed that for the circular polarization of laser light, a 100nm thin target is pushed forward as a compressed layer due to the radiation pressure of light. Whereas, the linear polarization seems to decompress the target drastically. 2D particle-in-cell simulations corroborate the experimental findings. Our results confirm the previous simulation studies investigating the fundamental role played by light polarization, finite focus spot size effect and eventually electron heating including the oblique incidence at the target edges.

  4. High-intensity interval exercise and cerebrovascular health: curiosity, cause, and consequence

    Science.gov (United States)

    Lucas, Samuel J E; Cotter, James D; Brassard, Patrice; Bailey, Damian M

    2015-01-01

    Exercise is a uniquely effective and pluripotent medicine against several noncommunicable diseases of westernised lifestyles, including protection against neurodegenerative disorders. High-intensity interval exercise training (HIT) is emerging as an effective alternative to current health-related exercise guidelines. Compared with traditional moderate-intensity continuous exercise training, HIT confers equivalent if not indeed superior metabolic, cardiac, and systemic vascular adaptation. Consequently, HIT is being promoted as a more time-efficient and practical approach to optimize health thereby reducing the burden of disease associated with physical inactivity. However, no studies to date have examined the impact of HIT on the cerebrovasculature and corresponding implications for cognitive function. This review critiques the implications of HIT for cerebrovascular function, with a focus on the mechanisms and translational impact for patient health and well-being. It also introduces similarly novel interventions currently under investigation as alternative means of accelerating exercise-induced cerebrovascular adaptation. We highlight a need for studies of the mechanisms and thereby also the optimal dose-response strategies to guide exercise prescription, and for studies to explore alternative approaches to optimize exercise outcomes in brain-related health and disease prevention. From a clinical perspective, interventions that selectively target the aging brain have the potential to prevent stroke and associated neurovascular diseases. PMID:25833341

  5. Beam Dynamics Studies of the ISOLDE Post-accelerator for the High Intensity and Energy Upgrade

    CERN Document Server

    Fraser, Matthew Alexander; Pasini, M

    2012-01-01

    The High Intensity and Energy (HIE) project represents a major upgrade of the ISOLDE (On-Line Isotope Mass Separator) nuclear facility at CERN with a mandate to significantly increase the energy, intensity and quality of the radioactive nuclear beams provided to the European nuclear physics community for research at the forefront of topics such as nuclear structure physics and nuclear astrophysics. The HIE-ISOLDE project focuses on the upgrade of the existing Radioactive ion beam EXperiment (REX) post-accelerator with the addition of a 40MVsuperconducting linac comprising 32 niobium sputter-coated copper quarter-wave cavities operating at 101.28 MHz and at an accelerating gradient close to 6 MV/m. The energy of post-accelerated radioactive nuclear beams will be increased from the present ceiling of 3 MeV/u to over 10 MeV/u, with full variability in energy, and will permit, amongst others, Coulomb interaction and few-nucleon transfer reactions to be carried out on the full inventory of radionuclides available ...

  6. Is High Intensity Functional Training (HIFT)/CrossFit® Safe for Military Fitness Training?

    Science.gov (United States)

    Poston, Walker S.C.; Haddock, Christopher K.; Heinrich, Katie M.; Jahnke, Sara A.; Jitnarin, Nattinee; Batchelor, David B.

    2016-01-01

    High-intensity functional training (HIFT) is a promising fitness paradigm that gained popularity among military populations. Rather than biasing workouts toward maximizing fitness domains such as aerobic endurance, HIFT workouts are designed to promote general physical preparedness. HIFT programs have proliferated due to concerns about the relevance of traditional physical training (PT), which historically focused on aerobic condition via running. Other concerns about traditional PT include: 1) the relevance of service fitness tests given current combat demands; 2) the perception that military PT is geared toward passing service fitness tests; and 3) that training for combat requires more than just aerobic endurance. Despite its’ popularity in the military, concerns have been raised about HIFT’s injury potential, leading to some approaches being labeled as “extreme conditioning programs” by several military and civilian experts. Given HIFT programs’ popularity in the military and concerns about injury, a review of data on HIFT injury potential is needed to inform military policy. The purpose of this review is to: 1) provide an overview of scientific methods used to appropriately compare injury rates among fitness activities; and 2) evaluate scientific data regarding HIFT injury risk compared to traditional military PT and other accepted fitness activities PMID:27391615

  7. Is High-Intensity Functional Training (HIFT)/CrossFit Safe for Military Fitness Training?

    Science.gov (United States)

    Poston, Walker S C; Haddock, Christopher K; Heinrich, Katie M; Jahnke, Sara A; Jitnarin, Nattinee; Batchelor, David B

    2016-07-01

    High-intensity functional training (HIFT) is a promising fitness paradigm that gained popularity among military populations. Rather than biasing workouts toward maximizing fitness domains such as aerobic endurance, HIFT workouts are designed to promote general physical preparedness. HIFT programs have proliferated as a result of concerns about the relevance of traditional physical training (PT), which historically focused on aerobic condition via running. Other concerns about traditional PT include: (1) the relevance of service fitness tests given current combat demands, (2) the perception that military PT is geared toward passing service fitness tests, and (3) that training for combat requires more than just aerobic endurance. Despite its' popularity in the military, concerns have been raised about HIFT's injury potential, leading to some approaches being labeled as "extreme conditioning programs" by several military and civilian experts. Given HIFT programs' popularity in the military and concerns about injury, a review of data on HIFT injury potential is needed to inform military policy. The purpose of this review is to: (1) provide an overview of scientific methods used to appropriately compare injury rates among fitness activities and (2) evaluate scientific data regarding HIFT injury risk compared to traditional military PT and other accepted fitness activities. Reprint & Copyright © 2016 Association of Military Surgeons of the U.S.

  8. Beam dynamics studies of the ISOLDE post-accelerator for the high intensity and energy upgrade

    CERN Document Server

    Fraser, M A

    2012-01-01

    The High Intensity and Energy (HIE) project represents a major upgrade of the ISOLDE (On-Line Isotope Mass Separator) nuclear facility at CERN with a mandate to significantly increase the energy, intensity and quality of the radioactive nuclear beams provided to the European nuclear physics community for research at the forefront of topics such as nuclear structure physics and nuclear astrophysics. The HIE-ISOLDE project focuses on the upgrade of the existing Radioactive ion beam EXperiment (REX) post-accelerator with the addition of a 40MVsuperconducting linac comprising 32 niobium sputter-coated copper quarter-wave cavities operating at 101.28 MHz and at an accelerating gradient close to 6 MV/m. The energy of post-accelerated radioactive nuclear beams will be increased from the present ceiling of 3 MeV/u to over 10 MeV/u, with full variability in energy, and will permit, amongst others, Coulomb interaction and few-nucleon transfer reactions to be carried out on the full inventory of radionuclides available ...

  9. An improved permanent magnet quadrupole design with larger good field region for high intensity proton linacs

    International Nuclear Information System (INIS)

    Mathew, Jose V.; Rao, S.V.L.S.; Krishnagopal, S.; Singh, P.

    2013-01-01

    The Low Energy High Intensity Proton Accelerator (LEHIPA), being developed at the Bhabha Atomic Research Centre (BARC) will produce a 20 MeV, 30 mA, continuous wave (CW) proton beam. At these low velocities, space-charge forces dominate, and could lead to larger beam sizes and beam halos. Hence in the design of the focusing lattice of the LEHIPA drift tube linac (DTL) using permanent magnet quadrupoles (PMQs), a larger good field region is preferred. Here we study, using the two dimensional (2D) and three dimensional (3D) simulation codes PANDIRA and RADIA, four different types of cylindrical PMQ designs: 16-segment trapezoidal Halbach configuration, bullet-nosed geometry and 8- and 16-segment rectangular geometries. The trapezoidal Halbach geometry is used in a variety of accelerators since it provides very high field gradients in small bores, while the bullet-nosed geometry, which is a combination of the trapezoidal and rectangular designs, is used in some DTLs. This study shows that a larger good field region is possible in the 16-segment rectangular design as compared to the Halbach and bullet-nosed designs, making it more attractive for high-intensity proton linacs. An improvement in good-field region by ∼16% over the Halbach design is obtained in the optimized 16-segment rectangular design, although the field gradient is lower by ∼20%. Tolerance studies show that the rectangular segment PMQ design is substantially less sensitive to the easy axis orientation errors and hence will be a better choice for DTLs. -- Highlights: • An improved permanent magnet quadrupole (PMQ) design with larger good field region is proposed. • We investigate four PMQ designs, including the widely used Halbach and bullet nosed designs. • Analytical calculations are backed by 2D as well as 3D numerical solvers, PANDIRA and RADIA. • The optimized 16 segment rectangular PMQ design is identified to exhibit the largest good field region. • The effect of easy axis orientation

  10. Design study of a radio-frequency quadrupole for high-intensity beams

    Science.gov (United States)

    Bahng, Jungbae; Kim, Eun-San; Choi, Bong-Hyuk

    2017-07-01

    The Rare isotope Accelerator Of Newness (RAON) heavy-ion accelerator has been designed for the Rare Isotope Science Project (RISP) in Korea. The RAON will produce heavy-ion beams from 660-MeV-proton to 200-MeV/u-uranium with continuous wave (CW) power of 400 kW to support research in various scientific fields. Its system consists of an ECR ion source, LEBTs with 10 keV/u, CW RFQ accelerator with 81.25 MHz and 500 keV/u, a MEBT system, and a SC linac. In detail, the driver linac system consists of a Quarter Wave Resonator (QWR) section with 81.25 MHz and a Half Wave Resonator (HWR) section with 162.5 MHz, Linac-1, and a Spoke Cavity section with 325 MHz, Linac-2. These linacs have been designed to optimize the beam parameters to meet the required design goals. At the same time, a light-heavy ion accelerator with high-intensity beam, such as proton, deuteron, and helium beams, is required for experiments. In this paper, we present the design study of the high intensity RFQ for a deuteron beam with energies from 30 keV/u to 1.5 MeV/u and currents in the mA range. This system is composed of an Penning Ionization Gauge ion source, short LEBT with a RF deflector, and shared SC Linac. In order to increase acceleration efficiency in a short length with low cost, the 2nd harmonic of 162.5 MHz is applied as the operation frequency in the D+ RFQ design. The D+ RFQ is designed with 4.97 m, 1.52 bravery factor. Since it operates with 2nd harmonic frequency, the beam should be 50% of the duty factor while the cavity should be operated in CW mode, to protect the downstream linac system. We focus on avoiding emittance growth by the space-charge effect and optimizing the RFQ to achieve a high transmission and low emittance growth. Both the RFQ beam dynamics study and RFQ cavity design study for two and three dimensions will be discussed. Supported by Korea University Future Research Grant

  11. ATLAS measurements of boosted object production

    CERN Document Server

    Arguin, Jean-Francois; The ATLAS collaboration

    2015-01-01

    This talk reviews ATLAS Standard Model measurements performed with boosted objects, i.e. boosted top quarks and W and Z bosons, which decay hadronically and are reconstructed as a single large radius jet.

  12. Effect of a multimodal high intensity exercise intervention in cancer patients undergoing chemotherapy: randomised controlled trial

    DEFF Research Database (Denmark)

    Adamsen, Lis; Quist, Morten; Andersen, Christina

    2009-01-01

    -up. INTERVENTION: Supervised exercise comprising high intensity cardiovascular and resistance training, relaxation and body awareness training, massage, nine hours weekly for six weeks in addition to conventional care, compared with conventional care. MAIN OUTCOME MEASURES: European Organization for Research...

  13. Work in progress at the North Area High Intensity Facility (NAHIF)

    CERN Multimedia

    CERN PhotoLab

    1979-01-01

    Installation of the H10, high intensity pion beamto the forst experiment NA10, showing, in particular, a pair of 5 m long, toroidally-magnetized muon collimators (or 'scrapers') designed to defocus negative muons around the negative pion beam.

  14. A high intensity beam handling system at the KEK-PS new experimental hall

    International Nuclear Information System (INIS)

    Tanaka, K.H.; Minakawa, M.; Yamanoi, Y.

    1991-01-01

    We would like to summarize newly developed technology for handling high-intensity beams. This was practically employed in the beam-handling system of primary protons at the KEK-PS new experimental hall. (author)

  15. Short-term effects of implemented high intensity shoulder elevation during computer work

    DEFF Research Database (Denmark)

    Larsen, Mette K; Samani, Afshin; Madeleine, Pascal

    2009-01-01

    contractions during the computer work. However, it is unknown how this may influence productivity, rate of perceived exertion (RPE) as well as activity and rest of neck-shoulder muscles during computer work. The aim of this study was to investigate short-term effects of a high intensity contraction...... on productivity, RPE and upper trapezius activity and rest during computer work and a subsequent pause from computer work. METHODS: 18 female computer workers performed 2 sessions of 15 min standardized computer mouse work preceded by 1 min pause with and without prior high intensity contraction of shoulder....... RESULTS: The main findings were that a high intensity shoulder elevation did not modify RPE, productivity or EMG activity of the upper trapezius during the subsequent pause and computer work. However, the high intensity contraction reduced the relative rest time of the uppermost (clavicular) trapezius...

  16. Photocathode fatigue of L-24 PM head due to high intensity light pulses

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, K.F.

    1980-01-08

    The sensitivity of radiation detectors which utilizes photomultipliers was determined after exposing the multiplier phototubes to high intensity light pulses. Test results found that generally less than a 5% change was found. (FS)

  17. High intensity radiated field external environments for civil aircraft operating in the United States of America

    Science.gov (United States)

    1998-12-01

    NAWCAD Patuxent River, Maryland, was tasked by the FAA to determine the High Intensity Radiated Field (HIRF) levels for civil aircraft operating in the U.S. The electromagnetic field survey will apply to civil aircraft seeking FAA certification under...

  18. Milne boost from Galilean gauge theory

    Science.gov (United States)

    Banerjee, Rabin; Mukherjee, Pradip

    2018-03-01

    Physical origin of Milne boost invariance of the Newton Cartan spacetime is traced to the effect of local Galilean boosts in its metric structure, using Galilean gauge theory. Specifically, we do not require any gauge field to understand Milne boost invariance.

  19. High Intensity Laser Therapy (HILT) versus TENS and NSAIDs in low back pain: clinical study

    Science.gov (United States)

    Zati, Allesandro; Fortuna, Damiano; Valent, A.; Filippi, M. V.; Bilotta, Teresa W.

    2004-09-01

    Low back pain, caused by lumbar disc herniation, is prevalently treated with a conservative approach. In this study we valued the efficacy of High Intensity Laser Therapy (HILT), compared with accepted therapies such as TENS and NSAIDs. Laser therapy obtained similar results in the short term, but better clinical effect over time than TENS and NSAIDs. In conclusion high intensity laser therapy appears to be a interesting new treatment, worthy of further research.

  20. Short-term effects of implemented high intensity shoulder elevation during computer work.

    Science.gov (United States)

    Larsen, Mette K; Samani, Afshin; Madeleine, Pascal; Olsen, Henrik B; Søgaard, Karen; Holtermann, Andreas

    2009-08-10

    Work-site strength training sessions are shown effective to prevent and reduce neck-shoulder pain in computer workers, but difficult to integrate in normal working routines. A solution for avoiding neck-shoulder pain during computer work may be to implement high intensity voluntary contractions during the computer work. However, it is unknown how this may influence productivity, rate of perceived exertion (RPE) as well as activity and rest of neck-shoulder muscles during computer work. The aim of this study was to investigate short-term effects of a high intensity contraction on productivity, RPE and upper trapezius activity and rest during computer work and a subsequent pause from computer work. 18 female computer workers performed 2 sessions of 15 min standardized computer mouse work preceded by 1 min pause with and without prior high intensity contraction of shoulder elevation. RPE was reported, productivity (drawings per min) measured, and bipolar surface electromyography (EMG) recorded from the dominant upper trapezius during pauses and sessions of computer work. Repeated measure ANOVA with Bonferroni corrected post-hoc tests was applied for the statistical analyses. The main findings were that a high intensity shoulder elevation did not modify RPE, productivity or EMG activity of the upper trapezius during the subsequent pause and computer work. However, the high intensity contraction reduced the relative rest time of the uppermost (clavicular) trapezius part during the subsequent pause from computer work (p shoulder elevation did not impose a negative impact on perceived effort, productivity or upper trapezius activity during computer work, implementation of high intensity contraction during computer work to prevent neck-shoulder pain may be possible without affecting the working routines. However, the unexpected reduction in clavicular trapezius rest during a pause with preceding high intensity contraction requires further investigation before high

  1. The Effects of Electrostimulation and Core Exercises on Recovery After High-Intensity Exercise

    OpenAIRE

    Ahmet Mor; Gökhan İpekoğlu; Cansel Arslanoglu; Kursat Acar; Erkal Arslanoglu

    2017-01-01

    Introduction and objectives: The purpose of this study was to determine the effects of electrostimulation and core exercises on recovery after high-intensity exercise. Methods: The participants of this study consists of 12 male bodybuilders who regularly train and between the ages 18-30. Tabata high intensity interval training (HIIT) was applied with different recovery methods to the athletes on three different days and the recovery levels of athletes were analysed. Heart rate and blood lacta...

  2. Negative beliefs about low back pain are associated with persistent high intensity low back pain.

    Science.gov (United States)

    Ng, Sin Ki; Cicuttini, Flavia M; Wang, Yuanyuan; Wluka, Anita E; Fitzgibbon, Bernadette; Urquhart, Donna M

    2017-08-01

    While previous cross-sectional studies have found that negative beliefs about low back pain are associated with pain intensity, the relationship between back beliefs and persistent low back pain is not well understood. This cohort study aimed to examine the role of back beliefs in persistent low back pain in community-based individuals. A hundred and ninety-two participants from a previous musculoskeletal health study were invited to take part in a two-year follow-up study. Beliefs about back pain were assessed by the Back Beliefs Questionnaire (BBQ) at baseline and low back pain intensity was measured by the Chronic Pain Grade Questionnaire at baseline and follow-up. Of the 150 respondents (78.1%), 16 (10.7%) reported persistent high intensity low back pain, 12 (8.0%) developed high intensity low back pain, in 16 (10.7%) their high intensity low back pain resolved and 106 (70.7%) experienced no high intensity low back pain. While participants were generally positive about low back pain (BBQ mean (SD) = 30.2 (6.4)), those with persistent high intensity pain reported greater negativity (BBQ mean (SD) = 22.6 (4.9)). Negative beliefs about back pain were associated with persistent high intensity low back pain after adjusting for confounders (M (SE) = 23.5 (1.6) vs. >30.1 (1.7), p back beliefs were associated with persistent high intensity low back pain over 2 years in community-based individuals. While further longitudinal studies are required, these findings suggest that targeting beliefs in programs designed to treat and prevent persistent high intensity low back pain may be important.

  3. Comparison of High-Intensity Laser Therapy and Ultrasound Treatment in the Patients with Lumbar Discopathy

    OpenAIRE

    Boyraz, Ismail; Yildiz, Ahmet; Koc, Bunyamin; Sarman, Hakan

    2015-01-01

    The aim of the present study was to evaluate the efficiency of high intensity laser and ultrasound therapy in patients who were diagnosed with lumbar disc herniation and who were capable of performing physical exercises. 65 patients diagnosed with lumbar disc were included in the study. The patients were randomly divided into three groups: Group 1 received 10 sessions of high intensity laser to the lumbar region, Group 2 received 10 sessions of ultrasound, and Group 3 received medical therapy...

  4. ada: An R Package for Stochastic Boosting

    Directory of Open Access Journals (Sweden)

    Mark Culp

    2006-09-01

    Full Text Available Boosting is an iterative algorithm that combines simple classification rules with ‘mediocre’ performance in terms of misclassification error rate to produce a highly accurate classification rule. Stochastic gradient boosting provides an enhancement which incorporates a random mechanism at each boosting step showing an improvement in performance and speed in generating the ensemble. ada is an R package that implements three popular variants of boosting, together with a version of stochastic gradient boosting. In addition, useful plots for data analytic purposes are provided along with an extension to the multi-class case. The algorithms are illustrated with synthetic and real data sets.

  5. ada: An R Package for Stochastic Boosting

    Directory of Open Access Journals (Sweden)

    Mark Culp

    2006-09-01

    Full Text Available Boosting is an iterative algorithm that combines simple classification rules with "mediocre" performance in terms of misclassification error rate to produce a highly accurate classification rule. Stochastic gradient boosting provides an enhancement which incorporates a random mechanism at each boosting step showing an improvement in performance and speed in generating the ensemble. ada is an R package that implements three popular variants of boosting, together with a version of stochastic gradient boosting. In addition, useful plots for data analytic purposes are provided along with an extension to the multi-class case. The algorithms are illustrated with synthetic and real data sets.

  6. High-Intensity Interval Training Interventions in Children and Adolescents: A Systematic Review.

    Science.gov (United States)

    Eddolls, William T B; McNarry, Melitta A; Stratton, Gareth; Winn, Charles O N; Mackintosh, Kelly A

    2017-11-01

    Whilst there is increasing interest in the efficacy of high-intensity interval training in children and adolescents as a time-effective method of eliciting health benefits, there remains little consensus within the literature regarding the most effective means for delivering a high-intensity interval training intervention. Given the global health issues surrounding childhood obesity and associated health implications, the identification of effective intervention strategies is imperative. The aim of this review was to examine high-intensity interval training as a means of influencing key health parameters and to elucidate the most effective high-intensity interval training protocol. Studies were included if they: (1) studied healthy children and/or adolescents (aged 5-18 years); (2) prescribed an intervention that was deemed high intensity; and (3) reported health-related outcome measures. A total of 2092 studies were initially retrieved from four databases. Studies that were deemed to meet the criteria were downloaded in their entirety and independently assessed for relevance by two authors using the pre-determined criteria. From this, 13 studies were deemed suitable. This review found that high-intensity interval training in children and adolescents is a time-effective method of improving cardiovascular disease biomarkers, but evidence regarding other health-related measures is more equivocal. Running-based sessions, at an intensity of >90% heart rate maximum/100-130% maximal aerobic velocity, two to three times a week and with a minimum intervention duration of 7 weeks, elicit the greatest improvements in participant health. While high-intensity interval training improves cardiovascular disease biomarkers, and the evidence supports the effectiveness of running-based sessions, as outlined above, further recommendations as to optimal exercise duration and rest intervals remain ambiguous owing to the paucity of literature and the methodological limitations of

  7. Giving top quark effective operators a boost

    CERN Document Server

    Englert, Christoph

    2016-01-01

    We investigate the prospects to systematically improve generic effective field theory-based searches for new physics in the top sector during LHC run 2 as well as the high luminosity phase. In particular, we assess the benefits of high momentum transfer final states on top EFT-fit as a function of systematic uncertainties in comparison with sensitivity expected from fully-resolved analyses focusing on $t\\bar t$ production. We find that constraints are typically driven by fully-resolved selections, while boosted top quarks can serve to break degeneracies in the global fit. This demystifies and clarifies the importance of high momentum transfer final states for global fits to new interactions in the top sector from direct measurements.

  8. High Intensity Interval Training Increases Natural Killer Cell Number and Function in Obese Breast Cancer-challenged Mice and Obese Women.

    Science.gov (United States)

    Barra, Nicole G; Fan, Isabella Y; Gillen, Jenna B; Chew, Marianne; Marcinko, Katarina; Steinberg, Gregory R; Gibala, Martin J; Ashkar, Ali A

    2017-12-01

    High intensity interval training (HIIT) boosts natural killer (NK) cell number and activity in normal weight breast cancer patients; however, whether this occurs in obese individuals is not well established. The goal of this study was to determine whether HIIT effectively boosts NK cells as a therapeutic strategy against breast cancer in an obese mouse model and in overweight/obese women. Diet induced female C57Bl/6 obese mice were assigned to undergo HIIT for four weeks or remain sedentary. Female participants were subjected to a six weeks HIIT protocol. HIIT mice acclimatized to treadmill running were subsequently injected with 5 × 10 5 polyoma middle T (MT) breast cancer cells intravenously. NK cell number and activation were monitored using flow cytometry, and tumor burden or lipid content evaluated from histological lung and liver tissues, respectively. In both mice and humans, circulating NK cell number and activation (CD3-NK1.1+CD27+ and CD3-CD56+, respectively) markedly increased immediately after HIIT. HIIT obese mice had reduced lung tumor burden compared to controls following MT challenge, and had diminished hepatic lipid deposition despite minimal body weight loss. Our findings demonstrate that HIIT can benefit obese individuals by enhancing NK cell number and activity, reducing tumor burden, and enhancing metabolic health.

  9. Effect of high intensity vs. soft-start halogen irradiation on light-cured resin-based composites. Part I. Temperature rise and polymerization shrinkage.

    Science.gov (United States)

    Hofmann, Norbert; Markert, Tanja; Hugo, Burkard; Klaiber, Bernd

    2003-12-01

    To determine polymerization shrinkage kinetics and temperature rise of light-cured resin-based composites after high intensity vs. soft-start quartz tungsten halogen irradiation. Shrinkage kinetics was evaluated using the "deflecting disk technique", modified for simultaneous measurement of temperature within the resin-based composite using a thermocouple. Additional irradiations after 60 and 65 minutes allowed the determination of temperature rises caused by radiation or by reaction heat. Four hybrids (Filtek Z250, Herculite, Solitaire 2, Tetric Ceram), an inhomogeneously filled hybrid (InTen-S) and a microfill (Filtek A110, formerly Silux Plus) were cured using the quartz tungsten halogen units Astralis 10 and Optilux 501 in the high intensity (A10 HiPo: 10 seconds at 1300 mW/cm2; OL Boost: 10 seconds at 1140 mW/cm2) or soft-start modes (A10 Pulse: increase to 700 mW/cm2 within 10 seconds, three periods of 2 seconds at 1300 mW/cm2 alternating with two periods of 2 seconds at 700 mW/cm2; OL Ramp: exponential increase within 10 seconds, followed by 10 seconds at 1140 mW/cm2). The soft-start protocols produced less contraction, and polymerization shrinkage started later and progressed slower (or: more slowly), compared to high intensity irradiation [correction]. The lowest shrinkage was observed for InTen-S, followed by Filtek Z250 and A110, whereas Solitaire 2, Herculite and Tetric Ceram scored highest for this parameter. Temperature rise was caused more or less equally by radiation and by reaction heat and reached values of up to 28.9 degrees C relative to a baseline of 37 degrees C. For some combinations of curing modes and resin-based composites, less heat was generated by the soft-start protocols and by Optilux 501.

  10. Effect of high-intensity training on endothelial function in patients with cardiovascular and cerebrovascular disease

    DEFF Research Database (Denmark)

    Kolmos, Mia; Krawcyk, Rikke Steen; Kruuse, Christina

    2016-01-01

    was to gather current knowledge on the effects of high-intensity training versus moderate-intensity continuous exercise on endothelial function in cardiovascular and cerebrovascular patients. METHODS: A systematic review was performed in PubMed database, Embase and Cochrane libraries and on PEDro using...... the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies were restricted to cardiovascular and cerebrovascular patients, and healthy subjects as general reference. Interventions comprised of high-intensity training alone, high-intensity training compared to moderate......OBJECTIVES: Exercise improves endothelial dysfunction, the key manifestation of cardiovascular and cerebrovascular disease, and is recommended in both cardiovascular and cerebrovascular rehabilitation. Disagreement remains, however, on the role of intensity of exercise. The purpose of this review...

  11. Effects of high-intensity training on cardiovascular risk factors in pre- and postmenopausal women

    DEFF Research Database (Denmark)

    Mandrup Jensen, Camilla Maria; Egelund, Jon; Nyberg, Michael Permin

    2017-01-01

    and cardiovascular disease in late pre- and early postmenopausal women, matched by age and body composition, and investigate the effect of high-intensity training. METHODS: A 3-month high-intensity aerobic training intervention, involving healthy, non-obese, late pre- (n=40) and early postmenopausal (n=39) women....... A three month intervention of high-intensity aerobic training reduces risk factors for type 2 diabetes and cardiovascular disease to a similar extent in late pre- and early postmenopausal women.......BACKGROUND: Menopause is associated with increased risk of cardiovascular disease and the causal factors have been proposed to be the loss of estrogen and the subsequent alterations of the hormonal milieu. However, which factors that contribute to the deterioration of cardio-metabolic health...

  12. Hydration and muscular performance: does fluid balance affect strength, power and high-intensity endurance?

    Science.gov (United States)

    Judelson, Daniel A; Maresh, Carl M; Anderson, Jeffrey M; Armstrong, Lawrence E; Casa, Douglas J; Kraemer, William J; Volek, Jeff S

    2007-01-01

    Significant scientific evidence documents the deleterious effects of hypohydration (reduced total body water) on endurance exercise performance; however, the influence of hypohydration on muscular strength, power and high-intensity endurance (maximal activities lasting >30 seconds but physiological demands of strength, power and high-intensity endurance couple with a lack of scientific support to argue against previous hypotheses that suggest alterations in cardiovascular, metabolic and/or buffering function represent the performance-reducing mechanism of hypohydration. On the other hand, hypohydration might directly affect some component of the neuromuscular system, but this possibility awaits thorough evaluation. A critical review of the available literature suggests hypohydration limits strength, power and high-intensity endurance and, therefore, is an important factor to consider when attempting to maximise muscular performance in athletic, military and industrial settings.

  13. Effects of high-intensity physical training on muscle fiber characteristics in poststroke patients

    DEFF Research Database (Denmark)

    Andersen, Jesper Løvind; Jørgensen, Jørgen R.; Zeeman, Peter

    2017-01-01

    INTRODUCTION: Stroke is a leading cause of disability worldwide. High-intensity physical training can improve muscle strength and gait speed, but adaptive mechanisms at the muscle cellular level are largely unknown. METHODS: Outpatients with poststroke hemiparesis participated in a 3-month...... rehabilitation program combining high-intensity strength and body-weight supported treadmill-training. Biopsies sampled bilaterally from vastus lateralis muscles, before, after, and at 1-year follow-up after intervention, were analyzed for fiber size, type, and capillarization. RESULTS: At baseline, paretic...... lower limbs had smaller muscle fiber size and lower type I and IIA and higher type IIX percentages than nonparetic lower limbs. Paretic lower limbs had increased type IIA fibers after training. At follow-up, no difference between the lower limbs remained. CONCLUSIONS: Although high-intensity training...

  14. High-intensity erotic visual stimuli de-activate the primary visual cortex in women.

    Science.gov (United States)

    Huynh, Hieu K; Beers, Caroline; Willemsen, Antoon; Lont, Erna; Laan, Ellen; Dierckx, Rudi; Jansen, Monique; Sand, Michael; Weijmar Schultz, Willibrord; Holstege, Gert

    2012-06-01

    The primary visual cortex, Brodmann's area (BA 17), plays a vital role in basic survival mechanisms in humans. In most neuro-imaging studies in which the volunteers have to watch pictures or movies, the primary visual cortex is similarly activated independent of the content of the pictures or movies. However, in case the volunteers perform demanding non-visual tasks, the primary visual cortex becomes de-activated, although the amount of incoming visual sensory information is the same. Do low- and high-intensity erotic movies, compared to neutral movies, produce similar de-activation of the primary visual cortex? Brain activation/de-activation was studied by Positron Emission Tomography scanning of the brains of 12 healthy heterosexual premenopausal women, aged 18-47, who watched neutral, low- and high-intensity erotic film segments. We measured differences in regional cerebral blood flow (rCBF) in the primary visual cortex during watching neutral, low-intensity erotic, and high-intensity erotic film segments. Watching high-intensity erotic, but not low-intensity erotic movies, compared to neutral movies resulted in strong de-activation of the primary (BA 17) and adjoining parts of the secondary visual cortex. The strong de-activation during watching high-intensity erotic film might represent compensation for the increased blood supply in the brain regions involved in sexual arousal, also because high-intensity erotic movies do not require precise scanning of the visual field, because the impact is clear to the observer. © 2012 International Society for Sexual Medicine.

  15. Influence of mature men way of life on highly intensive physical activity

    Directory of Open Access Journals (Sweden)

    O.B. Pryshva

    2017-04-01

    Full Text Available Highly intensive physical activity is the most effective for men’s health protection. In modern life conditions its level is insufficient. It requires organism’s appropriate physical activity, which is determined by way of life. Especially important it is before trainings. Purpose: to study special aspects of different intensity’s physical activity; of eating special food and sleeping regime of mature men before their highly intensive physical trainings. Material: in experiment men (n=26, age - 35-53years, who practice healthy life style and independent physical activity of high intensity, participated. We used bio-register Basis B1. Every day we registered: Peak - physical activity of different intensity; duration and quality of sleep; relative weight of consumed food. Besides, we calculated body mass index and physical condition. The study was conducted during 30 days in winter period. The following results were compared: indicators before not planned physical activity and average-monthly indicators. Results: Before arbitrary physical functioning we found in men: confident weakening of average intensity (by 9-11% and low intensity (by 10% physical activity; confident increase of consumed food’s relative weight (by 6.82%, vegetarian food (by 10.64% and raw food (by 7.61%; confident reduction of animal origin food (by 8.7%. No changes were found in duration and quality of sleep before highly intensive physical functioning. Conclusions: specific features of mature men’s way of life before their not planned highly intensive physical functioning are as follows: reduction of general physical activity; increase of consumed food. These factors facilitate energy accumulation in organism for its realization in highly intensive physical functioning the next day.

  16. Strategies for minimizing emittance growths in high intensity CW FEL injectors

    International Nuclear Information System (INIS)

    Liu, Hongxiu

    1996-01-01

    We discuss beam emittance growths in high intensity CW FEL injectors due to linear and non-linear space charge fields, phase space bifurcation, skew-quad effect, longitudinal momentum modification by space charges in bends, and equipartitioning, etc. We generalize Kim's RF laser gun theory to DC laser guns. We discuss the traditional free energy theory of emittance growth. The best strategies for designing high-intensity CW FEL injectors are derived, and their application to the design analysis of the CEBAF 10 MeV DC laser gun CW FEL injector test stand is discussed

  17. The Benefits of High Intensity Functional Training (HIFT) Fitness Programs for Military Personnel

    Science.gov (United States)

    Haddock, Christopher K.; Poston, Walker S.C.; Heinrich, Katie M.; Jahnke, Sara A.; Jitnarin, Nattinee

    2016-01-01

    High intensity functional training (HIFT) programs are designed to address multiple fitness domains, potentially providing improved physical and mental readiness in a changing operational environment. Programs consistent with HIFT principals such as CrossFit, SEALFIT and the US Marine Corps’ High Intensity Tactical Training (HITT) program are increasingly popular among military personnel. This article reviews the practical, health, body composition, and military fitness implications of HIFT exercise programs. We conclude that, given the unique benefits of HIFT, the military should consider evaluating whether these programs should be the standard for military fitness training. PMID:27849484

  18. High-intensity running in English FA Premier League soccer matches

    DEFF Research Database (Denmark)

    Bradley, Paul S.; Sheldon, William; Wooster, Blake

    2009-01-01

    The aims of this study were to (1) determine the activity profiles of a large sample of English FA Premier League soccer players and (2) examine high-intensity running during elite-standard soccer matches for players in various playing positions. Twenty-eight English FA Premier League games were...... with and without ball possession is reduced during various phases of elite-standard soccer matches and the activity profiles and fatigue patterns vary among playing positions. The current findings provide valuable information about the high-intensity running patterns of a large sample of elite-standard soccer...

  19. Effects of high-intensity resistance training on bone mineral density in young male powerlifters.

    Science.gov (United States)

    Tsuzuku, S; Ikegami, Y; Yabe, K

    1998-10-01

    The effects of high-intensity resistance training on bone mineral density (BMD) and its relationship to strength were investigated. Lumbar spine (L2-L4), proximal femur, and whole body BMD were measured in 10 male powerlifters and 11 controls using dual-energy X-ray absorptiometry (DXA). There were significant differences in lumbar spine and whole body BMD between powerlifters and controls, but not in proximal femur BMD. A significant correlation was found between lumbar spine BMD and powerlifting performance. These results suggest that high-intensity resistance training is effective in increasing the lumbar spine and whole body BMD.

  20. Focused ultrasound in ophthalmology

    Directory of Open Access Journals (Sweden)

    Silverman RH

    2016-09-01

    Full Text Available Ronald H Silverman1,2 1Department of Ophthalmology, Columbia University Medical Center, 2F.L. Lizzi Center for Biomedical Engineering, Riverside Research, New York, NY, USA Abstract: The use of focused ultrasound to obtain diagnostically significant information about the eye goes back to the 1950s. This review describes the historical and technological development of ophthalmic ultrasound and its clinical application and impact. Ultrasound, like light, can be focused, which is crucial for formation of high-resolution, diagnostically useful images. Focused, single-element, mechanically scanned transducers are most common in ophthalmology. Specially designed transducers have been used to generate focused, high-intensity ultrasound that through thermal effects has been used to treat glaucoma (via cilio-destruction, tumors, and other pathologies. Linear and annular transducer arrays offer synthetic focusing in which precise timing of the excitation of independently addressable array elements allows formation of a converging wavefront to create a focus at one or more programmable depths. Most recently, linear array-based plane-wave ultrasound, in which the array emits an unfocused wavefront and focusing is performed solely on received data, has been demonstrated for imaging ocular anatomy and blood flow. While the history of ophthalmic ultrasound extends back over half-a-century, new and powerful technologic advances continue to be made, offering the prospect of novel diagnostic capabilities. Keywords: ophthalmic ultrasound, ultrasound biomicroscopy (UBM, high-intensity focused ultrasound (HIFU, ultrafast imaging, Doppler imaging 

  1. Recursive bias estimation and L2 boosting

    Energy Technology Data Exchange (ETDEWEB)

    Hengartner, Nicolas W [Los Alamos National Laboratory; Cornillon, Pierre - Andre [INRA, FRANCE; Matzner - Lober, Eric [RENNE, FRANCE

    2009-01-01

    This paper presents a general iterative bias correction procedure for regression smoothers. This bias reduction schema is shown to correspond operationally to the L{sub 2} Boosting algorithm and provides a new statistical interpretation for L{sub 2} Boosting. We analyze the behavior of the Boosting algorithm applied to common smoothers S which we show depend on the spectrum of I - S. We present examples of common smoother for which Boosting generates a divergent sequence. The statistical interpretation suggest combining algorithm with an appropriate stopping rule for the iterative procedure. Finally we illustrate the practical finite sample performances of the iterative smoother via a simulation study.

  2. Effects of High Intensity Interval Training on Increasing Explosive Power, Speed, and Agility

    Science.gov (United States)

    Fajrin, F.; Kusnanik, N. W.; Wijono

    2018-01-01

    High Intensity Interval Training (HIIT) is a type of exercise that combines high-intensity exercise and low intensity exercise in a certain time interval. This type of training is very effective and efficient to improve the physical components. The process of improving athletes achievement related to how the process of improving the physical components, so the selection of a good practice method will be very helpful. This study aims to analyze how is the effects of HIIT on increasing explosive power, speed, and agility. This type of research is quantitative with quasi-experimental methods. The design of this study used the Matching-Only Design, with data analysis using the t-test (paired sample t-test). After being given the treatment for six weeks, the results showed there are significant increasing in explosive power, speed, and agility. HIIT in this study used a form of exercise plyometric as high-intensity exercise and jogging as mild or moderate intensity exercise. Increase was due to the improvement of neuromuscular characteristics that affect the increase in muscle strength and performance. From the data analysis, researchers concluded that, Exercises of High Intensity Interval Training significantly effect on the increase in Power Limbs, speed, and agility.

  3. High-intensity exercise attenuates postprandial lipaemia and markers of oxidative stress.

    Science.gov (United States)

    Gabriel, Brendan; Ratkevicius, Aivaras; Gray, Patrick; Frenneaux, Michael P; Gray, Stuart R

    2012-09-01

    Regular exercise can reduce the risk of CVD (cardiovascular disease). Although moderate-intensity exercise can attenuate postprandial TAG (triacylglycerol), high-intensity intermittent exercise might be a more effective method to improve health. We compared the effects of high-intensity intermittent exercise and 30 min of brisk walking on postprandial TAG, soluble adhesion molecules and markers of oxidative stress. Nine men each completed three 2-day trials. On day 1, subjects rested (control), walked briskly for 30 min (walking) or performed 5×30 s maximal sprints (high-intensity). On day 2, subjects consumed a high-fat meal for breakfast and 3 h later for lunch. Blood samples were taken at various times and analysed for TAG, glucose, insulin, ICAM-1 (intracellular adhesion molecule-1), VCAM-1 (vascular adhesion molecule-1), TBARS (thiobarbituric acid- reactive substances), protein carbonyls and β-hydroxybutyrate. On day 2 of the high-intensity trial, there was a lower (Ppostprandial TAG and markers of oxidative stress after the consumption of a high-fat meal.

  4. Intramedullary high intensity lesion on T2-weighted MR images in compressive cervical myelopathy

    Energy Technology Data Exchange (ETDEWEB)

    Kameyama, Takashi; Mizuno, Tetsuya; Yanagi, Tsutomu; Yasuda, Takeshi; Hirose, Yoshikiyo (Nagoya Daini Red Hospital (Japan))

    1991-11-01

    Magnetic resonance (MR) imaging was performed in 147 patients with compressive lesion of the cervical spinal canal. Intramedullary high intensity lesions were observed on T2-weighted or proton density spin-echo images in patients with cervical spondylotic myelopathy (20.0%) and ossification of the posterior longitudinal ligament of the cervical spine (25.7%), while such signal abnormality was not found in patients with cervical spondylotic radiculopathy. Frequency of this finding was proportional to clinical severity of myelopathy and degree of spinal cord compression. The pathophysiological basis of such signal abnormality was presumed to vary from acute edema to chronic myelomalacia. In most cases showing intramedullary high intensity lesion, the spinal cord was compressed at multiple levels, but the high intensity was usually found at a signal level where the compression was maximum. There was a good correlation between the neurological level and the high intensity level on MR images. Thus, the intramedullary lesion on MR images is considered to be the main site of lesion responsible for the neurological symptoms. (author).

  5. Intramedullary high intensity lesion on T2-weighted MR images in compressive cervical myelopathy

    International Nuclear Information System (INIS)

    Kameyama, Takashi; Mizuno, Tetsuya; Yanagi, Tsutomu; Yasuda, Takeshi; Hirose, Yoshikiyo

    1991-01-01

    Magnetic resonance (MR) imaging was performed in 147 patients with compressive lesion of the cervical spinal canal. Intramedullary high intensity lesions were observed on T2-weighted or proton density spin-echo images in patients with cervical spondylotic myelopathy (20.0%) and ossification of the posterior longitudinal ligament of the cervical spine (25.7%), while such signal abnormality was not found in patients with cervical spondylotic radiculopathy. Frequency of this finding was proportional to clinical severity of myelopathy and degree of spinal cord compression. The pathophysiological basis of such signal abnormality was presumed to vary from acute edema to chronic myelomalacia. In most cases showing intramedullary high intensity lesion, the spinal cord was compressed at multiple levels, but the high intensity was usually found at a signal level where the compression was maximum. There was a good correlation between the neurological level and the high intensity level on MR images. Thus, the intramedullary lesion on MR images is considered to be the main site of lesion responsible for the neurological symptoms. (author)

  6. High-intensity interval training and athletic performance in Taekwondo athletes.

    Science.gov (United States)

    Monks, Lynne; Seo, Myong-Won; Kim, Hyun-Bae; Jung, Hyun C; Song, Jong K

    2017-10-01

    The purpose of this study was to determine the effects of high-intensity interval training (HIIT) on athletic performance in Taekwondo athletes. Thirty-three male and female collegiate Taekwondo athletes were randomly divided into a HIIT group (N.=16) or a high-intensity continuous running (HICR) group (N.=17). The HIIT group undertook training of high-intensity sprints interspersed with active rest periods whilst the HICR group participated in high-intensity running for a continuous period. Both groups completed 11 sessions over 4 weeks. Physique, body composition, Wingate anaerobic test and VO2max test were measured. The vertical jump test, agility T-test and sit-ups were used to assess physical fitness. Repeated measures ANCOVAs with sex as a covariate were applied and significant level was set at 0.05. Following 11 sessions of training, significant improvements in anaerobic peak power (Pperformance in collegiate Taekwondo athletes. This could inform the future planning of Taekwondo athletes' pre-competition training, specifically the influence of training intensity on anaerobic capacity.

  7. Effects of music and video on perceived exertion during high-intensity exercise

    Directory of Open Access Journals (Sweden)

    Enoch C. Chow

    2017-03-01

    Conclusion: Music and video in combination may result in lower perceived exertion during high-intensity exercise when compared to music or video in isolation. Future research will be necessary to test if reductions in perceived exertion in response to dissociative attentional stimuli have implications for exercise adherence.

  8. Selected List of Low Energy Beam Transport Facilities for Light-Ion, High-Intensity Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Prost, L. R. [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)

    2016-02-17

    This paper presents a list of Low Energy Beam Transport (LEBT) facilities for light-ion, high-intensity accelerators. It was put together to facilitate comparisons with the PXIE LEBT design choices. A short discussion regarding the importance of the beam perveance in the choice of the transport scheme follows.

  9. Characterization of a proton beam driven by a high-intensity laser

    International Nuclear Information System (INIS)

    Sagisaka, Akito; Daido, Hiroyuki; Ogura, Koichi; Orimo, Satoshi; Hayashi, Yukio; Mori, Michiaki; Nishiuchi, Mamiko; Yogo, Akifumi; Kado, Masataka; Fukumi, Atsushi; Li, Zhong; Pirozhkov, Alexander S.; Nakamura, Shu

    2007-01-01

    High-energy protons are observed with a 3 μm thick tantalum target irradiated with a high intensity laser. The maximum proton energy is ∼900 keV. The half angle of the generated proton beam (>500 keV) is about 10deg. Characterization of the proton beam will significantly contribute to the proton applications. (author)

  10. Effects of 12 weeks high-intensity & reduced-volume training in elite athletes

    DEFF Research Database (Denmark)

    Kilen, Anders; Larsson, Tanja Hultengren; Jørgensen, Majke

    2014-01-01

    It was investigated if high-intensity interval training (HIT) at the expense of total training volume improves performance, maximal oxygen uptake and swimming economy. 41 elite swimmers were randomly allocated to a control (CON) or HIT group. For 12 weeks both groups trained ∼12 h per week. HIT...

  11. Effect of a High-intensity Interval Training method on maximum oxygen consumption in Chilean schoolchildren

    Directory of Open Access Journals (Sweden)

    Sergio Galdames-Maliqueo

    2017-12-01

    Full Text Available Introduction: The low levels of maximum oxygen consumption (VO2max evaluated in Chilean schoolchildren suggest the startup of trainings that improve the aerobic capacity. Objective: To analyze the effect of a High-intensity Interval Training method on maximum oxygen consumption in Chilean schoolchildren. Materials and methods: Thirty-two high school students from the eighth grade, who were divided into two groups, were part of the study (experimental group = 16 students and control group = 16 students. The main analyzed variable was the maximum oxygen consumption through the Course Navette Test. A High-intensity Interval training method was applied based on the maximum aerobic speed obtained through the Test. A mixed ANOVA was used for statistical analysis. Results: The experimental group showed a significant increase in the Maximum Oxygen Consumption between the pretest and posttest when compared with the control group (p < 0.0001. Conclusion: The results of the study showed a positive effect of the High-intensity Interval Training on the maximum consumption of oxygen. At the end of the study, it is concluded that High-intensity Interval Training is a good stimulation methodology for Chilean schoolchildren.

  12. Free mobilization and low- to high-intensity exercise in immobilization-induced muscle atrophy.

    Science.gov (United States)

    Kannus, P; Jozsa, L; Järvinen, T L; Kvist, M; Vieno, T; Järvinen, T A; Natri, A; Järvinen, M

    1998-04-01

    After 3 wk of immobilization, the effects of free cage activity and low- and high-intensity treadmill running (8 wk) on the morphology and histochemistry of the soleus and gastrocnemius muscles in male Sprague-Dawley rats were investigated. In both muscles, immobilization produced a significant (P < 0.001) increase in the mean percent area of intramuscular connective tissue (soleus: 18.9% in immobilized left hindlimb vs. 3.6% in nonimmobilized right hindlimb) and in the relative number of muscle fibers with pathological alterations (soleus: 66% in immobilized hindlimb vs. 6% in control), with a simultaneous significant (P < 0.001) decrease in the intramuscular capillary density (soleus: mean capillary density in the immobilized hindlimb only 63% of that in the nonimmobilized hindlimb) and muscle fiber size (soleus type I fibers: mean fiber size in the immobilized hindlimb only 69% of that in the nonimmobilized hindlimb). Many of these changes could not be corrected by free remobilization, whereas low- and high-intensity treadmill running clearly restored the changes toward control levels, the effect being most complete in the high-intensity running group. Collectively, these findings indicate that immobilization-induced pathological structural and histochemical alterations in rat calf muscles are, to a great extent, reversible phenomena if remobilization is intensified by physical training. In this respect, high-intensity exercise seems more beneficial than low-intensity exercise.

  13. Physics with a high-intensity proton accelerator below 30 GeV

    International Nuclear Information System (INIS)

    Hoffman, C.M.

    1982-01-01

    The types of physics that would be pursued at a high-intensity, moderate-energy proton accelerator are discussed. The discussion is drawn from the deliberations of the 30-GeV subgroup of the Fixed-Target Group at this workshop

  14. Effectiveness and Safety of High-Intensity Interval Training in Patients With Type 2 Diabetes

    Science.gov (United States)

    Francois, Monique E.

    2015-01-01

    IN BRIEF Recent research has shown that high-intensity interval training (HIIT) can promote improvements in glucose control and cardiovascular health in individuals with type 2 diabetes. This article summarizes the evidence and highlights the ways in which HIIT might be safely implemented as an adjunct to more traditional exercise approaches. PMID:25717277

  15. Spatial and spectral coherence in propagating high-intensity twin beams

    Czech Academy of Sciences Publication Activity Database

    Haderka, O.; Machulka, R.; Peřina ml., Jan; Allevi, A.; Bondani, M.

    2015-01-01

    Roč. 5, Sep (2015), s. 14365 ISSN 2045-2322 R&D Projects: GA ČR GAP205/12/0382 Institutional support: RVO:68378271 Keywords : spatial and spectral coherence * high-intensity twin beams Subject RIV: BH - Optics, Masers, Lasers Impact factor: 5.228, year: 2015

  16. A High Intensity Multi-Purpose D-D Neutron Generator for Nuclear Engineering Laboratories

    International Nuclear Information System (INIS)

    Ka-Ngo Leung; Jasmina L. Vujic; Edward C. Morse; Per F. Peterson

    2005-01-01

    This NEER project involves the design, construction and testing of a low-cost high intensity D-D neutron generator for teaching nuclear engineering students in a laboratory environment without radioisotopes or a nuclear reactor. The neutron generator was designed, fabricated and tested at Lawrence Berkeley National Laboratory (LBNL)

  17. Increased mortality in patients with severe COPD associated with high-intensity exercise

    DEFF Research Database (Denmark)

    Schaadt, Lone; Christensen, Robin; Kristensen, Lars Erik

    2016-01-01

    observed a striking mortality rate among participants who had attended the high-intensity rehabilitation courses (five deaths) compared to the standard rehabilitation (zero deaths). Four of the five deaths were COPD exacerbations. Fisher's exact test was statistically significant (P=0.046), as was a log...

  18. Scapular muscle activity from selected strengthening exercises performed at low and high intensity

    DEFF Research Database (Denmark)

    Andersen, Christoffer H; Zebis, Mette K; Saervoll, Charlotte

    2012-01-01

    for proper exercise prescription. This study determines scapular muscle activity during strengthening exercises for scapular muscles performed at low and high intensities (Borg-CR10 level 3 and 8). Surface electromyography (EMG) from selected scapular muscles was recorded during seven strengthening exercises...

  19. Reliability of a Novel High Intensity One Leg Dynamic Exercise Protocol to Measure Muscle Endurance.

    Directory of Open Access Journals (Sweden)

    Benjamin Pageaux

    Full Text Available We recently developed a high intensity one leg dynamic exercise (OLDE protocol to measure muscle endurance and investigate the central and peripheral mechanisms of muscle fatigue. The aims of the present study were to establish the reliability of this novel protocol and describe the isokinetic muscle fatigue induced by high intensity OLDE and its recovery. Eight subjects performed the OLDE protocol (time to exhaustion test of the right leg at 85% of peak power output three times over a week period. Isokinetic maximal voluntary contraction torque at 60 (MVC60, 100 (MVC100 and 140 (MVC140 deg/s was measured pre-exercise, shortly after exhaustion (13 ± 4 s, 20 s (P20 and 40 s (P40 post-exercise. Electromyographic (EMG signal was analyzed via the root mean square (RMS for all three superficial knee extensors. Mean time to exhaustion was 5.96 ± 1.40 min, coefficient of variation was 8.42 ± 6.24%, typical error of measurement was 0.30 min and intraclass correlation was 0.795. MVC torque decreased shortly after exhaustion for all angular velocities (all P < 0.001. MVC60 and MVC100 recovered between P20 (P < 0.05 and exhaustion and then plateaued. MVC140 recovered only at P40 (P < 0.05. High intensity OLDE did not alter maximal EMG RMS of the three superficial knee extensors during MVC. The results of this study demonstrate that this novel high intensity OLDE protocol could be reliably used to measure muscle endurance, and that muscle fatigue induced by high intensity OLDE should be examined within ~ 30 s following exhaustion.

  20. Psychophysiological effects of music on acute recovery from high-intensity interval training.

    Science.gov (United States)

    Jones, Leighton; Tiller, Nicholas B; Karageorghis, Costas I

    2017-03-01

    Numerous studies have examined the multifarious effects of music applied during exercise but few have assessed the efficacy of music as an aid to recovery. Music might facilitate physiological recovery via the entrainment of respiratory rhythms with music tempo. High-intensity exercise training is not typically associated with positive affective responses, and thus ways of assuaging negative affect warrant further exploration. This study assessed the psychophysiological effects of music on acute recovery and prevalence of entrainment in between bouts of high-intensity exercise. Thirteen male runners (M age =20.2±1.9years; BMI=21.7±1.7; V̇O 2 max=61.6±6.1mL·kg·min -1 ) completed three exercise sessions comprising 5×5-min bouts of high-intensity intervals interspersed with 3-min periods of passive recovery. During recovery, participants were administered positively-valenced music of a slow-tempo (55-65bpm), fast-tempo (125-135bpm), or a no-music control. A range of measures including affective responses, RPE, cardiorespiratory indices (gas exchange and pulmonary ventilation), and music tempo-respiratory entrainment were recorded during exercise and recovery. Fast-tempo, positively-valenced music resulted in higher Feeling Scale scores throughout recovery periods (pmusic-moderated differences in cardiorespiratory responses. In conclusion, fast-tempo, positively-valenced music applied during recovery periods engenders a more pleasant experience. However, there is limited evidence that music expedites cardiorespiratory recovery in between bouts of high-intensity exercise. These findings have implications for athletic training strategies and individuals seeking to make high-intensity exercise sessions more pleasant. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Numerical study of lipid translocation driven by nanoporation due to multiple high-intensity, ultrashort electrical pulses.

    Science.gov (United States)

    Sridhara, Viswanadham; Joshi, Ravindra P

    2014-03-01

    The dynamical translocation of lipids from one leaflet to another due to membrane permeabilization driven by nanosecond, high-intensity (>100kV/cm) electrical pulses has been probed. Our simulations show that lipid molecules can translocate by diffusion through water-filled nanopores which form following high voltage application. Our focus is on multiple pulsing, and such simulations are relevant to gauge the time duration over which nanopores might remain open, and facilitate continued lipid translocations and membrane transport. Our results are indicative of a N(½) scaling with pulse number for the pore radius. These results bode well for the use of pulse trains in biomedical applications, not only due to cumulative behaviors and in reducing electric intensities and pulsing hardware, but also due to the possibility of long-lived thermo-electric physics near the membrane, and the possibility for pore coalescence. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Experimental platform for investigations of high-intensity laser plasma interactions in the magnetic field of a pulsed power generator

    Science.gov (United States)

    Ivanov, V. V.; Maximov, A. V.; Swanson, K. J.; Wong, N. L.; Sarkisov, G. S.; Wiewior, P. P.; Astanovitskiy, A. L.; Covington, A. M.

    2018-03-01

    An experimental platform for the studying of high-intensity laser plasma interactions in strong magnetic fields has been developed based on the 1 MA Zebra pulsed power generator coupled with the 50-TW Leopard laser. The Zebra generator produces 100-300 T longitudinal and transverse magnetic fields with different types of loads. The Leopard laser creates plasma at an intensity of 1019 W/cm2 in the magnetic field of coil loads. Focusing and targeting systems are integrated in the vacuum chamber of the pulsed power generator and protected from the plasma debris and strong mechanical shock. The first experiments with plasma at laser intensity >2 × 1018 W/cm2 demonstrated collimation of the laser produced plasma in the axial magnetic field strength >100 T.

  3. Investigation of optical properties of an overdense magnetized plasma lens in the interaction with high-intensity Gaussian laser pulses

    Science.gov (United States)

    Ghorbanalilu, M.; Shokri, B.

    2018-03-01

    Self-focusing of a high-intensity circularly polarized Gaussian laser pulse by an overdense magnetized thin plasma lens is numerically investigated. The quasi-static axial magnetic field can be produced by inverse Faraday effect (IFE) mechanism in laser-plasma interaction. It has been shown that the inclusion of self-transparency, ponderomotive force, and magnetic field effects significantly affect the self-focusing properties. When the strength of the magnetic field increases, the self-focusing property is enhanced for the right and is weakened for the left-handed circularly polarized laser pulse. The ponderomotive force repels electrons from the axis and drives electron cavitation and as a result further lowers the plasma frequency. When the influence of the ponderomotive force is taken into account, self-focusing for both polarizations is strongly affected. The clear difference between the effects of the right- and left-handed circularly polarized pulses may lead us to use them for different experimental applications.

  4. Advanced Airfoils Boost Helicopter Performance

    Science.gov (United States)

    2007-01-01

    Carson Helicopters Inc. licensed the Langley RC4 series of airfoils in 1993 to develop a replacement main rotor blade for their Sikorsky S-61 helicopters. The company's fleet of S-61 helicopters has been rebuilt to include Langley's patented airfoil design, and the helicopters are now able to carry heavier loads and fly faster and farther, and the main rotor blades have twice the previous service life. In aerial firefighting, the performance-boosting airfoils have helped the U.S. Department of Agriculture's Forest Service control the spread of wildfires. In 2003, Carson Helicopters signed a contract with Ducommun AeroStructures Inc., to manufacture the composite blades for Carson Helicopters to sell

  5. ATLAS boosted object tagging 2

    CERN Document Server

    Caudron, Julien; The ATLAS collaboration

    2015-01-01

    A detailed study into the optimal techniques for identifying boosted hadronically decaying W or Z bosons is presented. Various algorithms for reconstructing, grooming and tagging bosonic jets are compared for W bosons with a wide range of transverse momenta using 8 TeV data and 8 TeV and 13 TeV MC simulations. In addition, given that a hadronic jet has been identified as resulting from the hadronic decay of a W or Z, a technique is developed to discriminate between W and Z bosons. The modeling of the tagging variables used in this technique is studied using 8 TeV pp collision data and systematic uncertainties for the tagger efficiency and fake rates are evaluated.

  6. Beam dynamics in high intensity cyclotrons including neighboring bunch effects: Model, implementation, and application

    Directory of Open Access Journals (Sweden)

    J. J. Yang (杨建俊

    2010-06-01

    Full Text Available Space-charge effects, being one of the most significant collective effects, play an important role in high intensity cyclotrons. However, for cyclotrons with small turn separation, other existing effects are of equal importance. Interactions of radially neighboring bunches are also present, but their combined effects have not yet been investigated in any great detail. In this paper, a new particle in the cell-based self-consistent numerical simulation model is presented for the first time. The model covers neighboring bunch effects and is implemented in the three-dimensional object-oriented parallel code OPAL-cycl, a flavor of the OPAL framework. We discuss this model together with its implementation and validation. Simulation results are presented from the PSI 590 MeV ring cyclotron in the context of the ongoing high intensity upgrade program, which aims to provide a beam power of 1.8 MW (CW at the target destination.

  7. Moderate-to-High Intensity Physical Exercise in Patients with Alzheimer's Disease: A Randomized Controlled Trial

    DEFF Research Database (Denmark)

    Hoffmann, Kristine; Sobol, Nanna A; Frederiksen, Kristian S

    2016-01-01

    Background: Studies of physical exercise in patients with Alzheimer’s disease (AD) are few and results have been inconsistent. Objective: To assess the effects of a moderate-to-high intensity aerobic exercise program in patients with mild AD. Methods: In a randomized controlled trial, we recruited...... 200 patients with mild AD to a supervised exercise group (60-min sessions three times a week for 16 weeks) or to a control group. Primary outcome was changed from baseline in cognitive performance estimated by Symbol Digit Modalities Test (SDMT) in the intention-to-treat (ITT) group. Secondary...... baseline in SDMT as compared with the control group (mean: 4.2, 95% CI 0.5 to 7.9, p = 0.028), suggesting a dose-response relationship between exercise and cognition. Conclusions: This is the first randomized controlled trial with supervised moderate-to-high intensity exercise in patients with mild AD...

  8. HIGH-INTENSITY EFFECTS IN THE LONGITUDINAL MOTION OF STORED PARTICLE BEAMS

    Energy Technology Data Exchange (ETDEWEB)

    Sessler, Andrew M.

    1973-02-01

    A brief review is given of the various self-field phenomena associated with the longitudinal motion of particles in storage rings. Although there are some high-intensity phenomena for which the coupling of longitudinal and transverse motion is essential, such as, for example, the headtail effect; the great majority of high-intensity phenomena primarily involve either longitudinal or transverse degrees of freedom. In this review, we restrict our attention to phenomena which are essentially longitudinal in nature. It is convenient to consider separately the behavior of unbunched (coasting) and bunched (external RF system in operation) beams. Detailed experimental information on coasting beams has been obtained on the ISR, on the (old) CERN electron model CESAR, and on electron ring accelerators. All high-energy electron storage rings have bunched beams and, of course, so do synchrotrons, so that there are a large number of sources of experimental information about the longitudinal motion of bunched beams.

  9. Recovery of a soil under different vegetation one year after a high intensity wildfire

    Directory of Open Access Journals (Sweden)

    A. Martín

    2013-05-01

    Full Text Available Studies on soil recovery in fragile ecosystems following high intensity wildfires are scarce. The aim of the present investigation is to evaluate the impact of a high intensity wildfire in an ecosystem under different vegetation (shrubland and pinewood located at Vilardevós (Galicia, NW Spain and highly susceptible to suffer soil erosion due to the steep relief and high erositivity of the rainfall. Soil samples were collected from the A horizon (0-5 cm 1 year after the fire and soil quality was evaluated by analysis of several physical, chemical and biochemical properties measured in the fraction chemical properties > physical properties. The data also showed that the fire impact was different depending on the soil vegetation considered (shrubland and pinewood. Moreover, the data confirmed the slow soil recovery in this fragile ecosystem and, therefore, the need of adopting post-fire stabilisation and rehabilitation treatments in order to minimize the post-fire erosion and soil degradation.

  10. Dose rate laser simulation tests adequacy: Shadowing and high intensity effects analysis

    International Nuclear Information System (INIS)

    Nikiforov, A.Y.; Skorobogatov, P.K.

    1996-01-01

    The adequacy of laser based simulation of the flash X-ray effects in microcircuits may be corrupted mainly due to laser radiation shadowing by the metallization and the non-linear absorption in a high intensity range. The numerical joint solution of the optical equations and the fundamental system of equations in a two-dimensional approximation were performed to adjust the application range of laser simulation. As a result the equivalent dose rate to laser intensity correspondence was established taking into account the shadowing as well as the high intensity effects. The simulation adequacy was verified in the range up to 4·10 11 rad(Si)/s with the comparative laser test of a specially designed test structure

  11. High-intensity interval training has positive effects on performance in ice hockey players.

    Science.gov (United States)

    Naimo, M A; de Souza, E O; Wilson, J M; Carpenter, A L; Gilchrist, P; Lowery, R P; Averbuch, B; White, T M; Joy, J

    2015-01-01

    In spite of the well-known benefits that have been shown, few studies have looked at the practical applications of high-intensity interval training (HIIT) on athletic performance. This study investigated the effects of a HIIT program compared to traditional continuous endurance exercise training. 24 hockey players were randomly assigned to either a continuous or high-intensity interval group during a 4-week training program. The interval group (IG) was involved in a periodized HIIT program. The continuous group (CG) performed moderate intensity cycling for 45-60 min at an intensity that was 65% of their calculated heart rate reserve. Body composition, muscle thickness, anaerobic power, and on-ice measures were assessed pre- and post-training. Muscle thickness was significantly greater in IG (p=0.01) when compared to CG. The IG had greater values for both ∆ peak power (pperformance. © Georg Thieme Verlag KG Stuttgart · New York.

  12. Beam Dynamics Studies for High-Intensity Beams in the CERN Proton Synchrotron

    CERN Document Server

    AUTHOR|(CDS)2082016; Benedikt, Michael

    With the discovery of the Higgs boson, the existence of the last missing piece of the Standard Model of particle physics (SM) was confirmed. However, even though very elegant, this theory is unable to explain, for example, the generation of neutrino masses, nor does it account for dark energy or dark matter. To shed light on some of these open questions, research in fundamental particle physics pursues two complimentary approaches. On the one hand, particle colliders working at the high-energy frontier, such as the Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN), located in Geneva, Switzerland, are utilized to investigate the fundamental laws of nature. Alternatively, fixed target facilities require high-intensity beams to create a large flux of secondary particles to investigate, for example, rare particle decay processes, or to create neutrino beams. This thesis investigates limitations arising during the acceleration of high-intensity beams at the CERN Proton Synchrotro...

  13. Transverse Beam Halo Measurements at High Intensity Neutrino Source (HINS) using Vibrating Wire Monitor

    Energy Technology Data Exchange (ETDEWEB)

    Chung, M.; Hanna, B.; Scarpine, V.; Shiltsev, V.; Steimel, J.; Artinian, S.; Arutunian, S.

    2015-02-26

    The measurement and control of beam halos will be critical for the applications of future high-intensity hadron linacs. In particular, beam profile monitors require a very high dynamic range when used for the transverse beam halo measurements. In this study, the Vibrating Wire Monitor (VWM) with aperture 60 mm was installed at the High Intensity Neutrino Source (HINS) front-end to measure the transverse beam halo. A vibrating wire is excited at its resonance frequency with the help of a magnetic feedback loop, and the vibrating and sensitive wires are connected through a balanced arm. The sensitive wire is moved into the beam halo region by a stepper motor controlled translational stage. We study the feasibility of the vibrating wire for the transverse beam halo measurements in the low-energy front-end of the proton linac.

  14. Moderate-to-high intensity aerobic exercise in patients with mild to moderate Alzheimer's disease

    DEFF Research Database (Denmark)

    Frederiksen, Kristian S; Sobol, Nanna; Beyer, Nina

    2014-01-01

    OBJECTIVES: Physical exercise may modulate neuropathology and symptoms of Alzheimer's disease (AD). This pilot study assessed the feasibility of conducting a study of moderate-to-high intensity aerobic exercise in home-dwelling patients with mild AD. METHODS: An uncontrolled preintervention......-postintervention test design with a single group receiving the same intervention. A total of eight patients with mild to moderate AD from the Copenhagen Memory clinic were included in the study. The intervention lasted for 14 weeks and consisted of supervised, 1-h sessions of aerobic exercise three times per week (50......-to-high intensity aerobic exercise in community-dwelling patients with mild AD. Our findings indicate that aspects such as a longer adaptation period, information about injury prevention, and need for involvement and support from caregivers should be addressed when planning an exercise intervention in an AD...

  15. High-intensity interval training in facioscapulohumeral muscular dystrophy type 1

    DEFF Research Database (Denmark)

    Andersen, Grete; Heje, Karen; Buch, Astrid Emile

    2017-01-01

    Increasing evidence suggests that high-intensity training (HIT) is a time-efficient exercise strategy to improve fitness. HIT has never been explored in neuromuscular diseases, likely because it may seem counterintuitive. A single session of high-intensity exercise has been studied without signs...... fitness (3.3 ml O2/min/kg, CI 1.2-5.5, P training effect on other outcomes. Patients preferred HIT over strength and moderate-intensity aerobic training. It may seem...... counterintuitive to perform HIT in muscular dystrophies, but this RCT shows that regular HIT is safe, efficacious, and well liked by moderately affected patients with FSHD1, which suggests that HIT is a feasible method for rehabilitating patients with FSHD1....

  16. High intensity training improves exercise performance in elite women volleyball players during a competitive season

    DEFF Research Database (Denmark)

    Purkhús, Elisabeth; Krustrup, Peter; Mohr, Magni

    2016-01-01

    improved by 12.6 and 18.3% post-intervention, respectively, with greater (Phigh intensity in-season training performed as interval running improved agility, repeated sprint ability and high intensity intermittent exercise performance in elite......Elite women volleyball players (n=25; age; 19±5 yrs, height; 171±7 cm, weight; 63±10 kg; means±SD) volunteered to participate in the study. They were randomized into a high intensity training group (HIT; n=13) and a control group (CON; n=12). In addition to the normal team training and games, HIT...... performed 6-10x30-s all-out running intervals separated by 3-min recovery periods 3 times per wk during a 4-wk in-season period, while CON only completed team training sessions and games. Pre and post intervention all players completed the Arrowhead Agility Test (AAT), a repeated sprint test (RST; 5x30 m...

  17. Automated system for the determination of patterns of high-intensity LEDs

    International Nuclear Information System (INIS)

    Baly, L.; Bolaño, L.; Arteche, R.; Broco, Y.; Quesada, I.; Rodríguez, E.

    2008-01-01

    Determination of high-intensity LEDs lighting patterns is an important step for the simulation and planning of arrays of these devices configurations. Currently there are systems based on CCD cameras able to efficiently solve this problem, however the high cost of these is a limiting factor for use. Another limitation of CCD cameras, is that they are designed for light levels much lower than those produced by a high-intensity LED. In this paper we present an automated system for the determination of the intensity of LEDs based on the scan point to point patterns. The results of the analysis of a type of LED based on arrays of bars with built-in optical system is presented.

  18. Changes in satellite cells in human skeletal muscle after a single bout of high intensity exercise

    DEFF Research Database (Denmark)

    Crameri, Regina M; Langberg, Henning; Magnusson, Peter

    2004-01-01

    No studies to date have reported activation of satellite cells in vivo in human muscle after a single bout of high intensity exercise. In this investigation, eight individuals performed a single bout of high intensity exercise with one leg, the contralateral leg being the control. A significant...... increase in mononuclear cells staining for the neural cell adhesion molecule (N-CAM) and fetal antigen 1 (FA1) were observed within the exercised human vastus lateralis muscle on days 4 and 8 post exercise. In addition, a significant increase in the concentration of the FA1 protein was determined...... in the control leg. Despite this increase in N-CAM- and FA1-positive mononuclear cells, an increased expression of myogenin and the neonatal isoform of the myosin heavy chain (MHCn) was not observed. Interestingly, myofibre lesions resulting from extensive damage to the proteins within the myofibre, particularly...

  19. Effects of High-Intensity Blood Flow Restriction Exercise on Muscle Fatigue

    Directory of Open Access Journals (Sweden)

    Neto Gabriel R.

    2014-07-01

    Full Text Available Strength training combined with blood flow restriction (BFR have been used to improve the levels of muscle adaptation. The aim of this paper was to investigate the acute effect of high intensity squats with and without blood flow restriction on muscular fatigue levels. Twelve athletes (aged 25.95 ± 0.84 years were randomized into two groups: without Blood Flow Restriction (NFR, n = 6 and With Blood Flow Restriction (WFR, n = 6 that performed a series of free weight squats with 80% 1-RM until concentric failure. The strength of the quadriceps extensors was assessed in a maximum voluntary isometric contraction integrated to signals from the surface electromyogram. The average frequency showed significant reductions in the WFR group for the vastus lateralis and vastus medialis muscles, and intergroup only for the vastus medialis. In conclusion, a set of squats at high intensity with BFR could compromise muscle strength immediately after exercise, however, differences were not significant between groups.

  20. Perspectives on high-intensity interval exercise for health promotion in children and adolescents

    Science.gov (United States)

    Bond, Bert; Weston, Kathryn L; Williams, Craig A; Barker, Alan R

    2017-01-01

    Physical activity lowers future cardiovascular disease (CVD) risk; however, few children and adolescents achieve the recommended minimum amount of daily activity. Accordingly, there is virtue in identifying the efficacy of small volumes of high-intensity exercise for health benefits in children and adolescents for the primary prevention of CVD risk. The purpose of this narrative review is to provide a novel overview of the available literature concerning high-intensity interval-exercise (HIIE) interventions in children and adolescents. Specifically, the following areas are addressed: 1) outlining the health benefits observed following a single bout of HIIE, 2) reviewing the role of HIIE training in the management of pediatric obesity, and 3) discussing the effectiveness of school-based HIIE training. In total, 39 HIIE intervention studies were included in this review. Based upon the available data, a single bout of high-intensity exercise provides a potent stimulus for favorable, acute changes across a range of cardiometabolic outcomes that are often superior to a comparative bout of moderate-intensity exercise (14 studies reviewed). HIIE also promotes improvements in cardiorespiratory fitness and cardiometabolic health status in overweight and obese children and adolescents (10 studies reviewed) and when delivered in the school setting (15 studies reviewed). We thus conclude that high-intensity exercise is a feasible and potent method of improving a range of cardiometabolic outcomes in children and adolescents. However, further work is needed to optimize the delivery of HIIE interventions in terms of participant enjoyment and acceptability, to include a wider range of health outcomes, and to control for important confounding variables (eg, changes in diet and habitual physical activity). Finally, research into the application of HIIE training interventions to children and adolescents of different ages, sexes, pubertal status, and sociocultural backgrounds is

  1. A Highly intense DC muon source, MuSIC and muon CLFV search

    International Nuclear Information System (INIS)

    Hino, Y.; Kuno, Y.; Sato, A.; Sakamoto, H.; Matsumoto, Y.; Tran, N.H.; Hashim, I.H.; Fukuda, M.; Hayashida, Y.; Ogitsu, T.; Yamamoto, A.; Yoshida, M.

    2014-01-01

    MuSIC is a new muon facility, which provides the world's highest intense muon beam with continuous time structure at Research Center of Nuclear Physics (RCNP), Osaka University. It's intensity is designed to be 10 8 muons per second with only 0.4 kW proton beam. Such a high intense muon beam is very important for searches of rare decay processes, for example search for the muon to electron conversion

  2. High-intensity cyclotrons for radioisotope production and accelerator driven systems

    Energy Technology Data Exchange (ETDEWEB)

    Jongen, Y.; Vandeplassche, D.; Kleeven, W.; Beeckman, W.; Zaremba, S.; Lannoye, G.; Stichelbaut, F

    2002-04-22

    IBA recently proposed a new method to extract high-intensity positive ion beams from a cyclotron based on the concept of auto-extraction. We review the design of a 14 MeV, multi-milliampere cyclotron using this new technology. IBA is also involved in the design of the accelerator system foreseen to drive the MYRRHA facility, a multipurpose neutron source developed jointly by SCK-CEN and IBA.

  3. Fat Utilization During High-Intensity Exercise: When Does It End?

    OpenAIRE

    Peric, Ratko; Meucci, Marco; Nikolovski, Zoran

    2016-01-01

    Background This study examined substrate oxidation at high-intensity exercise and aimed to determine when fat oxidation ends (FATmin). We hypothesized the existence of a connection between the anaerobic threshold (AnT) and FATmin point. Methods Breath-by-breath data obtained from indirect calorimetry during a graded treadmill test were used to measure substrate oxidation and maximal oxygen uptake (VO2max) on 47 males (30 athletes (ATL) and 17 non-athletes (NATL)). Pearson correlation coeffici...

  4. Report from the NSLS workshop: Sources and applications of high intensity uv-vuv light

    International Nuclear Information System (INIS)

    Johnson, E.D.; Hastings, J.B.

    1990-01-01

    A workshop was held to evaluate sources and applications of high intensity, ultra violet (UV) radiation for biological, chemical, and materials sciences. The proposed sources are a UV free electron laser (FEL) driven by a high brightness linac and undulators in long, straight sections of a specially designed low energy (400 MeV) storage ring. These two distinct types of sources will provide a broad range of scientific opportunities that were discussed in detail during the workshop

  5. Analysis of plasma channels in mm-scale plasmas formed by high intensity laser beams

    International Nuclear Information System (INIS)

    Murakami, R; Habara, H; Iwawaki, T; Uematsu, Y; Tanaka, K A; Ivancic, S; Anderson, K; Haberberger, D; Stoeckl, C; Theobald, W; Sakagami, H

    2016-01-01

    A plasma channel created by a high intensity infrared laser beam was observed in a long scale-length plasma (L ∼ 240 μm) with the angular filter refractometry technique, which indicated a stable channel formation up to the critical density. We analyzed the observed plasma channel using a rigorous ray-tracing technique, which provides a deep understanding of the evolution of the channel formation. (paper)

  6. Postexercise cold-water immersion improves intermittent high-intensity exercise performance in normothermia.

    Science.gov (United States)

    McCarthy, Avina; Mulligan, James; Egaña, Mikel

    2016-11-01

    A brief cold water immersion between 2 continuous high-intensity exercise bouts improves the performance of the latter compared with passive recovery in the heat. We investigated if this effect is apparent in normothermic conditions (∼19 °C), employing an intermittent high-intensity exercise designed to reflect the work performed at the high-intensity domain in team sports. Fifteen young active men completed 2 exhaustive cycling protocols (Ex1 and Ex2: 12 min at 85% ventilatory threshold (VT) and then an intermittent exercise alternating 30-s at 40% peak power (P peak ) and 30 s at 90% P peak to exhaustion) separated by 15 min of (i) passive rest, (ii) 5-min cold-water immersion at 8 °C, and (iii) 10-min cold-water immersion at 8 °C. Core temperature, heart rate, rates of perceived exertion, and oxygen uptake kinetics were not different during Ex1 among conditions. Time to failure during the intermittent exercise was significantly (P immersions (7.2 ± 3.5 min and 7.3 ± 3.3 min, respectively) compared with passive rest (5.8 ± 3.1 min). Core temperature, heart rate, and rates of perceived exertion were significantly (P immersions compared with passive rest. The time constant of phase II oxygen uptake response during the 85% VT bout of Ex2 was not different among the 3 conditions. A postexercise, 5- to 10-min cold-water immersion increases subsequent intermittent high-intensity exercise compared with passive rest in normothermia due, at least in part, to reductions in core temperature, circulatory strain, and effort perception.

  7. Report from the NSLS workshop: Sources and applications of high intensity uv-vuv light

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, E.D.; Hastings, J.B. (eds.)

    1990-01-01

    A workshop was held to evaluate sources and applications of high intensity, ultra violet (UV) radiation for biological, chemical, and materials sciences. The proposed sources are a UV free electron laser (FEL) driven by a high brightness linac and undulators in long, straight sections of a specially designed low energy (400 MeV) storage ring. These two distinct types of sources will provide a broad range of scientific opportunities that were discussed in detail during the workshop.

  8. Report from the NSLS workshop: Sources and applications of high intensity uv-vuv light

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, E.D.; Hastings, J.B. [eds.

    1990-12-31

    A workshop was held to evaluate sources and applications of high intensity, ultra violet (UV) radiation for biological, chemical, and materials sciences. The proposed sources are a UV free electron laser (FEL) driven by a high brightness linac and undulators in long, straight sections of a specially designed low energy (400 MeV) storage ring. These two distinct types of sources will provide a broad range of scientific opportunities that were discussed in detail during the workshop.

  9. High-intensity cycle interval training improves cycling and running performance in triathletes.

    Science.gov (United States)

    Etxebarria, Naroa; Anson, Judith M; Pyne, David B; Ferguson, Richard A

    2014-01-01

    Effective cycle training for triathlon is a challenge for coaches. We compared the effects of two variants of cycle high-intensity interval training (HIT) on triathlon-specific cycling and running. Fourteen moderately-trained male triathletes ([Formula: see text]O2peak 58.7 ± 8.1 mL kg(-1) min(-1); mean ± SD) completed on separate occasions a maximal incremental test ([Formula: see text]O2peak and maximal aerobic power), 16 × 20 s cycle sprints and a 1-h triathlon-specific cycle followed immediately by a 5 km run time trial. Participants were then pair-matched and assigned randomly to either a long high-intensity interval training (LONG) (6-8 × 5 min efforts) or short high-intensity interval training (SHORT) (9-11 × 10, 20 and 40 s efforts) HIT cycle training intervention. Six training sessions were completed over 3 weeks before participants repeated the baseline testing. Both groups had an ∼7% increase in [Formula: see text]O2peak (SHORT 7.3%, ±4.6%; mean, ±90% confidence limits; LONG 7.5%, ±1.7%). There was a moderate improvement in mean power for both the SHORT (10.3%, ±4.4%) and LONG (10.7%, ±6.8%) groups during the last eight 20-s sprints. There was a small to moderate decrease in heart rate, blood lactate and perceived exertion in both groups during the 1-h triathlon-specific cycling but only the LONG group had a substantial decrease in the subsequent 5-km run time (64, ±59 s). Moderately-trained triathletes should use both short and long high-intensity intervals to improve cycling physiology and performance. Longer 5-min intervals on the bike are more likely to benefit 5 km running performance.

  10. 650 mm long liquid hydrogen target for use in a high intensity electron beam

    International Nuclear Information System (INIS)

    Mark, J.W.

    1983-07-01

    This paper describes a 650 mm long liquid hydrogen target constructed for use in the high intensity electron beam at the Stanford Linear Accelerator Center. The main design problem was to construct a target that would permit the heat deposited by the electron beam to be removed rapidly without boiling the hydrogen so as to maintain constant target density for optimum data taking. Design requirements, construction details and operating experience are discussed

  11. Targets for production of high-intensity radioactive ion-beams

    International Nuclear Information System (INIS)

    Hagebo, E.; Hoff, P.; Steffensen, K.

    1991-01-01

    The recent developments of target systems for production of high intensity radioactive ion-beams at the ISOLDE mass separators is described. Methods for chemically selective production through separation of molecular ions are outlined and the effects of the addition of reactive gases has been studied. Results and further possible applications in the light element region are discussed. (author) 10 refs.; 9 figs.; 1 tab

  12. The effect of pre-exercise galactose and glucose ingestion on high-intensity endurance cycling.

    OpenAIRE

    O'Hara, J; Carroll, S; Cooke, CB; King, RF

    2014-01-01

    This study evaluated the effects of the pre-exercise (30 minutes) ingestion of galactose (Gal) or glucose (Glu) on endurance capacity as well as glycemic and insulinemic responses. Ten trained male cyclists completed 3 randomized high-intensity cycling endurance tests. Thirty minutes before each trial, cyclists ingested 1 L of either 40 g of glucose, 40 g of galactose, or a placebo in a double-blind manner. The protocol comprised 20 minutes of progressive incremental exercise (70-85% maximal ...

  13. Proceedings of the third ICFA mini-workshop on high intensity, high brightness hadron accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Roser, T.

    1997-11-01

    The third mini-workshop on high intensity, high brightness hadron accelerators was held at Brookhaven National Laboratory on May 7-9, 1997 and had about 30 participants. The workshop focussed on rf and longitudinal dynamics issues relevant to intense and/or bright hadron synchrotrons. A plenary session was followed by four sessions on particular topics. This document contains copies of the viewgraphs used as well as summaries written by the session chairs.

  14. Design concept of radiation control system for the high intensity proton accelerator facility

    CERN Document Server

    Miyamoto, Y; Harada, Y; Ikeno, K

    2002-01-01

    Description is given for the characteristic radiation environment for the High Intensity Proton Accelerator Facility and the design concept of the radiation control system of it. The facility is a large scale accelerator complex consisting of high energy proton accelerators carrying the highest beam intensity in the world and the related experimental facilities and therefore provides various issues relevant to the radiation environment. The present report describes the specifications for the radiation control system for the facility, determined in consideration of these characteristics.

  15. In-Season High-Intensity Interval Training Improves Conditioning In High School Soccer Players

    OpenAIRE

    HOWARD, NEAL; STAVRIANEAS, STASINOS

    2017-01-01

    Soccer is characterized by high aerobic demands interspersed with frequent bursts of anaerobic activity. High-intensity interval training (HIIT) is considered a viable alternative to traditional endurance conditioning and offers the additional time-saving benefits of anaerobic training. We hypothesized that HIIT will compare favorably to traditional (aerobic-based) soccer conditioning over the course of a high school soccer season. Junior varsity soccer players were split into control (CON, n...

  16. Effects and Sustainability of a 13-Day High-Intensity Shock Microcycle in Soccer

    OpenAIRE

    Wahl, Patrick; Güldner, Matthias; Mester, Joachim

    2014-01-01

    The preseason in soccer is a short period of 6-8 weeks where conditional abilities, technical and tactical elements need to be trained. Therefore, time is lacking to perform long term preparation periods for different abilities, especially endurance training. There is evidence that the implementation of high-intensity shock microcycles in preseason training could be one way to improve physical performance in a short period of time. Therefore, the purpose of the present study was to examine th...

  17. SPES: A new cyclotron-based facility for research and applications with high-intensity beams

    Science.gov (United States)

    Maggiore, M.; Campo, D.; Antonini, P.; Lombardi, A.; Manzolaro, M.; Andrighetto, A.; Monetti, A.; Scarpa, D.; Esposito, J.; Silvestrin, L.

    2017-06-01

    In 2016, Laboratori Nazionali di Legnaro (Italy) started the commissioning of a new accelerator facility based on a high-power cyclotron able to deliver proton beams up to 70 MeV of energy and 700 μA current. Such a machine is the core of the Selective Production of Exotic Species (SPES) project whose main goal is to provide exotics beam for nuclear and astrophysics research and to deliver high-intensity proton beams for medical applications and neutrons generator.

  18. Short-term effects of implemented high intensity shoulder elevation during computer work

    OpenAIRE

    Larsen, Mette K; Samani, Afshin; Madeleine, Pascal; Olsen, Henrik B; S?gaard, Karen; Holtermann, Andreas

    2009-01-01

    Abstract Background Work-site strength training sessions are shown effective to prevent and reduce neck-shoulder pain in computer workers, but difficult to integrate in normal working routines. A solution for avoiding neck-shoulder pain during computer work may be to implement high intensity voluntary contractions during the computer work. However, it is unknown how this may influence productivity, rate of perceived exertion (RPE) as well as activity and rest of neck-shoulder muscles during c...

  19. The impact of brief high-intensity exercise on blood glucose levels

    OpenAIRE

    Adams, O Peter

    2013-01-01

    O Peter AdamsFaculty of Medical Sciences, the University of the West Indies, Cave Hill Campus, St Michael, BarbadosBackground: Moderate-intensity exercise improves blood glucose (BG), but most people fail to achieve the required exercise volume. High-intensity exercise (HIE) protocols vary. Maximal cycle ergometer sprint interval training typically requires only 2.5 minutes of HIE and a total training time commitment (including rest and warm up) of 25 minutes per session. The effect of brief ...

  20. A Highly intense DC muon source, MuSIC and muon CLFV search

    Energy Technology Data Exchange (ETDEWEB)

    Hino, Y.; Kuno, Y.; Sato, A. [Department of Physics, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043 (Japan); Sakamoto, H. [Department of Physics, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043 (Japan); Research Center of Nuclear Physics, 10-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan); Matsumoto, Y.; Tran, N.H.; Hashim, I.H. [Department of Physics, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043 (Japan); Fukuda, M.; Hayashida, Y. [Research Center of Nuclear Physics, 10-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan); Ogitsu, T.; Yamamoto, A.; Yoshida, M. [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan)

    2014-08-15

    MuSIC is a new muon facility, which provides the world's highest intense muon beam with continuous time structure at Research Center of Nuclear Physics (RCNP), Osaka University. It's intensity is designed to be 10{sup 8} muons per second with only 0.4 kW proton beam. Such a high intense muon beam is very important for searches of rare decay processes, for example search for the muon to electron conversion.

  1. APPLICATION OF UAL TO HIGH INTENSITY BEAM DYNAMICS STUDIES IN THE SNS ACCUMULATOR RING

    International Nuclear Information System (INIS)

    MALITSKY, N.; FEDOTOV, A.V.; WEI, J.

    2002-01-01

    The SNS Ring off-line parallel simulation environment based on the Unified Accelerator Libraries (UAL) has been implemented and used for extensive full-scale beam dynamics studies arising in high-intensity rings. The paper describes the structure of this environment and its application to the development and analysis of the SNS accumulator ring beam loss model including a complex combination of several physical effects

  2. APPLICATION OF UAL TO HIGH INTENSITY BEAM DYNAMICS STUDIES IN THE SNS ACCUMULATOR RING.

    Energy Technology Data Exchange (ETDEWEB)

    MALITSKY,N.; FEDOTOV,A.V.; WEI,J.

    2002-06-03

    The SNS Ring off-line parallel simulation environment based on the Unified Accelerator Libraries (UAL) has been implemented and used for extensive full-scale beam dynamics studies arising in high-intensity rings. The paper describes the structure of this environment and its application to the development and analysis of the SNS accumulator ring beam loss model including a complex combination of several physical effects.

  3. Effects of high-intensity physical training on muscle fiber characteristics in poststroke patients.

    Science.gov (United States)

    Andersen, Jesper L; Jørgensen, Jørgen R; Zeeman, Peter; Bech-Pedersen, Daniel T; Sørensen, Jane; Ara, Ignacio; Andersen, Lars L

    2017-11-01

    Stroke is a leading cause of disability worldwide. High-intensity physical training can improve muscle strength and gait speed, but adaptive mechanisms at the muscle cellular level are largely unknown. Outpatients with poststroke hemiparesis participated in a 3-month rehabilitation program combining high-intensity strength and body-weight supported treadmill-training. Biopsies sampled bilaterally from vastus lateralis muscles, before, after, and at 1-year follow-up after intervention, were analyzed for fiber size, type, and capillarization. At baseline, paretic lower limbs had smaller muscle fiber size and lower type I and IIA and higher type IIX percentages than nonparetic lower limbs. Paretic lower limbs had increased type IIA fibers after training. At follow-up, no difference between the lower limbs remained. Although high-intensity training appeared not to induce changes in fiber size or capillarization, increased type IIA fiber percentages may contribute to muscle power and endurance, which is crucial for functional capacity. Muscle Nerve 56: 954-962, 2017. © 2016 Wiley Periodicals, Inc.

  4. HIGH INTENSITY EXERCISE AND FLEXIBILITY OF THE LOWER LIMBS: DOSE-EFFECT STUDY

    Directory of Open Access Journals (Sweden)

    João Rafael Valentim-Silva

    Full Text Available ABSTRACT Introduction: Sports scientists have been studying the phenomenon involving different types of exercises and their influence on other activities. Stretching exercises have a negative influence on muscular strength and power output, as do high intensity or long duration cardiovascular training. Nevertheless, several studies have found the opposite to be true Nevertheless, few investigations have studied the opposite. Objective: To determine whether high intensity power exercise influences muscular flexibility in an acute manner. Methods: A sample of forty-three male and female young adults aged between 18 and 28 years, with a mean age of 22.88 + 3.04 years, who have practiced physical activity for at least six months. To determine flexibility, the sit-and-reach test was used. For the high intensity training, a 45º leg press was used. A 10-rep movement was performed at 85% of 1 RM, in both pre- and post-tests. Statistic analysis was conducted using the ANOVA and Scheffer's post-hoc tests, with a level of significance for differences of < 0.05. Results: Comparison of the pre- and post-tests proved to be statistically significant from the baseline from the fourth to the seventh repetitions. Conclusion: Strength exercises at 85% of 1RM seem to significantly increase range of motion in an acute manner, and the growth of this range of motion has a dose-effect response.

  5. High intensity aerobic interval training improves peak oxygen consumption in patients with metabolic syndrome: CAT

    Directory of Open Access Journals (Sweden)

    Alexis Espinoza Salinas

    2014-06-01

    Full Text Available Introduction A number of cardiovascular risk factors characterizes the metabolic syndrome: insulin resistance (IR, low HDL cholesterol and high triglycerides. The aforementioned risk factors lead to elevated levels of abdominal adipose tissue, resulting in oxygen consumption deficiency. Purpose To verify the validity and applicability of using high intensity interval training (HIIT in subjects with metabolic syndrome and to answer the following question: Can HIIT improve peak oxygen consumption? Method The systematic review "Effects of aerobic interval training on exercise capacity and metabolic risk factors in individuals with cardiometabolic disorders" was analyzed. Results Data suggests high intensity aerobic interval training increases peak oxygen consumption by a standardized mean difference of 3.60 mL/kg-1/min-1 (95% confidence interval, 0.28-4.91. Conclusion In spite of the methodological shortcomings of the primary studies included in the systematic review, we reasonably conclude that implementation of high intensity aerobic interval training in subjects with metabolic syndrome, leads to increases in peak oxygen consumption.

  6. Effects of High-Intensity Endurance Exercise on Epidermal Barriers against Microbial Invasion

    Science.gov (United States)

    Eda, Nobuhiko; Shimizu, Kazuhiro; Suzuki, Satomi; Lee, Eunjae; Akama, Takao

    2013-01-01

    For athletes, preventing infectious disease on skin is important. Examination measurement of epidermal barriers could provide valuable information on the risk of skin infections. The aim of this study was to determine the effects of high-intensity endurance exercise on epidermal barriers. Six healthy adult males (age; 22.3 ± 1.6 years) performed bicycle exercise at 75%HRmax for 60 min from 18:30 to 19:30. Skin surface samples were measured 18:30 (pre), 19:30 (post), 20:30 (60 min), and 21:30 (120 min). Secretory immunoglobulin A (SIgA) and human β-defensin 2 (HBD-2) concentrations were measured using an enzyme-linked immunosorbent assay (ELISA). SIgA concentration at pre was significantly higher than at post, 60 min and 120 min (p immune barrier and physical barrier and enhance the risk of skin infection. On the other hand, the biochemical barrier increases after exercise, and our findings suggest that this barrier might supplement the compromised function of other skin barriers. Key points The immune barrier and physical barrier might be depressed and the risk of skin infection might be enhanced by high-intensity endurance exercise. The biochemical barrier increases after high-intensity endurance exercise and might supplement the compromised function of other skin barriers. We recommend that athletes maintain their skin surface in good condition, for example, by showering immediately after sports activities and using moisturizers. PMID:24149724

  7. High-Intensity Interval Training in Heart Transplant Recipients: A Systematic Review with Meta-Analysis.

    Science.gov (United States)

    Perrier-Melo, Raphael José; Figueira, Fernando Augusto Marinho Dos Santos; Guimarães, Guilherme Veiga; Costa, Manoel da Cunha

    2018-02-01

    Heart transplantation (HTx) is considered an efficient and gold-standard procedure for patients with end-stage heart failure. After surgery, patients have lower aerobic power (VO2max) and compensatory hemodynamic responses. The aim of the present study was to assess through a systematic review with meta-analysis whether high-intensity interval training (HIIT) can provide benefits for those parameters. This is a systematic review with meta-analysis, which searched the databases and data portals PubMed, Web of Science, Scopus, Science Direct and Wiley until December 2016 (pairs). The following terms and descriptors were used: "heart recipient" OR "heart transplant recipient" OR "heart transplant" OR "cardiac transplant" OR "heart graft". Descriptors via DeCS and Mesh were: "heart transplantation'' OR "cardiac transplantation". The words used in combination (AND) were: "exercise training" OR "interval training" OR "high intensity interval training" OR "high intensity training" OR "anaerobic training" OR "intermittent training" OR "sprint training". The initial search identified 1064 studies. Then, only those studies assessing the influence of HIIT on the post-HTx period were added, resulting in three studies analyzed. The significance level adopted was 0.05. Heart transplant recipients showed significant improvement in VO2peak, heart rate and peak blood pressure in 8 to 12 weeks of intervention.

  8. Benefits of High-Intensity Intensive Care Unit Physician Staffing under the Affordable Care Act

    Directory of Open Access Journals (Sweden)

    Sachin Logani

    2011-01-01

    Full Text Available The Affordable Care Act signed into law by President Obama, with its value-based purchasing program, is designed to link payment to quality processes and outcomes. Treatment of critically ill patients represents nearly 1% of the gross domestic product and 25% of a typical hospital budget. Data suggest that high-intensity staffing patterns in the intensive care unit (ICU are associated with cost savings and improved outcomes. We evaluate the literature investigating the cost-effectiveness and clinical outcomes of high-intensity ICU physician staffing as recommended by The Leapfrog Group (a consortium of companies that purchase health care for their employees and identify ways to overcome barriers to nationwide implementation of these standards. Hospitals that have implemented the Leapfrog initiative have demonstrated reductions in mortality and length of stay and increased cost savings. High-intensity staffing models appear to be an immediate cost-effective way for hospitals to meet the challenges of health care reform.

  9. Effects of high-intensity interval cycling performed after resistance training on muscle strength and hypertrophy.

    Science.gov (United States)

    Tsitkanou, S; Spengos, K; Stasinaki, A-N; Zaras, N; Bogdanis, G; Papadimas, G; Terzis, G

    2017-11-01

    Aim of the study was to investigate whether high-intensity interval cycling performed immediately after resistance training would inhibit muscle strength increase and hypertrophy expected from resistance training per se. Twenty-two young men were assigned into either resistance training (RE; N = 11) or resistance training plus high-intensity interval cycling (REC; N = 11). Lower body muscle strength and rate of force development (RFD), quadriceps cross-sectional area (CSA) and vastus lateralis muscle architecture, muscle fiber type composition and capillarization, and estimated aerobic capacity were evaluated before and after 8 weeks of training (2 times per week). Muscle strength and quadriceps CSA were significantly and similarly increased after both interventions. Fiber CSA increased significantly and similarly after both RE (type I: 13.6 ± 3.7%, type IIA: 17.6 ± 4.4%, type IIX: 23.2 ± 5.7%, P strength/hypertrophy after 2 months of training, while it prompts aerobic capacity and muscle capillarization. The addition of high-intensity cycling after heavy-resistance exercise may decrease RFD partly due to muscle architectural changes. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. HIGH INTENSITY PHYSICAL TRAINING EXERCISE PROGRAM IN IMPROVING BREAST CANCER RELATED FATIGUE

    Directory of Open Access Journals (Sweden)

    Intsar S. Wake

    2016-02-01

    Full Text Available Background: Breast cancer is a prevalent disease that requires intense and prolonged treatments. Because of improved detection and treatment options, the mortality rate from breast cancer has decreased, greatly increasing the number of survivors who are living with the disease and its side effects. Fatigue is one of the most common debilitating symptoms experienced by patients with cancer. It is a persistent feeling of exhaustion and decreased physical and mental capacity unrelieved by rest or sleep. The purpose of current study was to evaluate the effect of high intensity physical training exercise program in improving breast cancer related fatigue. Methods: Forty six patients suffering from breast cancer related fatigue, were randomly divided into two groups of equal number. Exercise group (E; received high intensity physical training program while Control group (C received usual medical care and kept their habitual activity. The intensity of fatigue and quality of life score were measured at the beginning and after eight weeks of treatment. Results: Results of the study showed that there was significant reduction of fatigue after eight weeks in exercise (E group more than control group with the percentage of improvement was 53%, 2% respectively. As regard to QOL measurements, there was significant increase of QOL score after treatment in exercise (E group more than control group with the percentage of improvement was 43%, 3% respectively. Conclusion: High intensity physical exercise program may have beneficial effects in reduction of fatigue intensity and thereby improving quality of life in breast cancer patient.

  11. Beetroot Juice Supplementation Improves High-Intensity Intermittent Type Exercise Performance in Trained Soccer Players

    Science.gov (United States)

    Nyakayiru, Jean; Jonvik, Kristin L.; Trommelen, Jorn; Pinckaers, Philippe J. M.; Senden, Joan M.; van Loon, Luc J. C.; Verdijk, Lex B.

    2017-01-01

    It has been shown that nitrate supplementation can enhance endurance exercise performance. Recent work suggests that nitrate ingestion can also increase intermittent type exercise performance in recreational athletes. We hypothesized that six days of nitrate supplementation can improve high-intensity intermittent type exercise performance in trained soccer players. Thirty-two male soccer players (age: 23 ± 1 years, height: 181 ± 1 m, weight: 77 ± 1 kg, playing experience: 15.2 ± 0.5 years, playing in the first team of a 2nd or 3rd Dutch amateur league club) participated in this randomized, double-blind cross-over study. All subjects participated in two test days in which high-intensity intermittent running performance was assessed using the Yo-Yo IR1 test. Subjects ingested nitrate-rich (140 mL; ~800 mg nitrate/day; BR) or a nitrate-depleted beetroot juice (PLA) for six subsequent days, with at least eight days of wash-out between trials. The distance covered during the Yo-Yo IR1 was the primary outcome measure, while heart rate (HR) was measured continuously throughout the test, and a single blood and saliva sample were collected just prior to the test. Six days of BR ingestion increased plasma and salivary nitrate and nitrite concentrations in comparison to PLA (p effectively improves high-intensity intermittent type exercise performance in trained soccer players. PMID:28327503

  12. Repeated High Intensity Bouts with Long Recovery: Are Bicarbonate or Carbohydrate Supplements an Option?

    Directory of Open Access Journals (Sweden)

    Thomas Stöggl

    2014-01-01

    Full Text Available The effects of varying recovery modes and the influence of preexercise sodium bicarbonate and carbohydrate ingestion on repeated high intensity performance, acid-base response, and recovery were analyzed in 12 well-trained males. They completed three repeated high intensity running bouts to exhaustion with intervening recovery periods of 25 min under the following conditions: sodium bicarbonate, active recovery (BIC; carbohydrate ingestion, active recovery (CHO; placebo ingestion, active recovery (ACTIVE; placebo ingestion, passive recovery (PASSIVE. Blood lactate (BLa, blood gases, heart rate, and time to exhaustion were collected. The three high intensity bouts had a duration of 138±9, 124±6, and 121±6 s demonstrating a decrease from bout 1 to bout 3. Supplementation strategy had no effect on performance in the first bout, even with differences in pH and bicarbonate (HCO3-. Repeated sprint performance was not affected by supplementation strategy when compared to ACTIVE, while PASSIVE resulted in a more pronounced decrease in performance compared with all other interventions. BIC led to greater BLa, pH, and HCO3- values compared with all other interventions, while for PASSIVE the opposite was found. BLa recovery was lowest in PASSIVE; recovery in pH, and HCO3- was lower in PASSIVE and higher in BIC.

  13. Changes in technique and efficiency after high-intensity exercise in cross-country skiers.

    Science.gov (United States)

    Åsan Grasaas, Christina; Ettema, Gertjan; Hegge, Ann Magdalen; Skovereng, Knut; Sandbakk, Øyvind

    2014-01-01

    This study investigated changes in technique and efficiency after high-intensity exercise to exhaustion in elite cross-country skiers. Twelve elite male skiers completed 4 min submaximal exercise before and after a high-intensity incremental test to exhaustion with the G3 skating technique on a 5% inclined roller-ski treadmill. Kinematics and kinetics were monitored by instrumented roller skis, work rate was calculated as power against roller friction and gravity, aerobic metabolic cost was determined from gas exchange, and blood lactate values indicated the anaerobic contribution. Gross efficiency was the work rate divided by aerobic metabolic rate. A recovery period of 10 min between the incremental test and the posttest was included to allow the metabolic values to return to baseline. Changes in neuromuscular fatigue in upper and lower limbs before and after the incremental test were indicated by peak power in concentric bench press and squat-jump height. From pretest to posttest, cycle length decreased and cycle rate increased by approximately 5% (P squat-jump performance remained unaltered. Elite cross-country skiers demonstrated a less efficient technique and shorter cycle length during submaximal roller-ski skating after high-intensity exercise. However, there were no changes in ski forces or peak power in the upper and lower limbs that could explain these differences.

  14. [Effect of high-intensity alternating magnetic field 
on viscosity of sheep blood].

    Science.gov (United States)

    Tao, Pengxian; Wu, Xiangyang; Zhao, Lingzhi; Wang, Feng; Xia, Qi; Peng, Yan; Gao, Bingren

    2017-12-28

    To explore the changes of blood viscosity in high-intensity alternating magnetic field and the mechanisms.
 Methods: Five adult sheep were randomly selected and the blood samples were placed in high-intensity alternating magnetic field. Before and after exposure, the blood samples were taken and divided into 2 groups: a control group and a magnetic field group. The blood rheology and transmission electron microscopy (TEM) were performed.
 Results: Compared to the control group, the high shear viscosity of whole blood was decreased in the magnetic field group (P<0.05); the whole blood low shear viscosity and plasma viscosity were also decreased (both P<0.01). TEM showed the changes in red blood cell morphology and the double concave disc curvature. The radian of double concave disc and cell volume in the magnetic field group was larger than those in the control group.
 Conclusion: The high intensity alternating magnetic field may affect the distribution of surface charge and molecular current in blood cells, which in turn decrease the aggregation of cells and the blood viscosity.

  15. Atomic motion in a high-intensity standing wave laser field

    International Nuclear Information System (INIS)

    Saez Ramdohr, L.F.

    1987-01-01

    This work discusses the effect of a high-intensity standing wave laser field on the motion of neutral atoms moving with a relatively high velocity. The analysis involves a detailed calculation of the force acting on the atoms and the calculation of the diffusion tensor associated with the fluctuations of the quantum force operator. The high-intensity laser field limit corresponds to a Rabi frequency much greater than the natural rate of the atom. The general results are valid for any atomic velocity. Results are then specialized to the case of slow and fast atoms where the Doppler shift of the laser frequency due to the atomic motion is either smaller or larger than the natural decay rate of the atom. The results obtained for the force and diffusion tensor are applied to a particular ideal experiment that studies the evolution of a fast atomic beam crossing a high-intensity laser beam. The theories developed previously, for a similar laser configuration, discuss only the low atomic velocities case and not the more realistic case of fast atoms. Here, an approximate solution of the equation for the distribution is obtained. Starting from the approximate distribution function, the deflection angle and dispersion angle for the atomic beam with respect to the free motion are calculated

  16. Joint Cooling does not Hinder Athletic Performance during High-intensity Intermittent Exercise.

    Science.gov (United States)

    Kim, H; Lee, D; Choi, H-M; Park, J

    2016-07-01

    We examined the effects of ankle and knee joint cooling on 20-m sprint times and maximal vertical jump heights during high-intensity intermittent exercise. 21 healthy collegiate male basketball (n=14) and handball players (n=7) underwent 3 experimental sessions. Each session consisted of four 15-min quarters of high-intensity intermittent exercises including various intensities of 20-m shuttle running and jumping. A 20-min bilateral joint cooling (ankle, knee, or control-no cooling: in a counterbalanced order) was applied before quarters 1 and 3. After joint cooling, no warm-up activity other than the exercise protocol was given. The 20-m sprint times and maximal vertical jump heights in each experimental session were recorded at baseline (prior to quarter-1) and during each quarter. To test joint cooling effects over time, we performed 3×5 mixed model ANOVAs. Neither ankle nor knee joint cooling changed 20-m sprint times (F8,280=1.45; p=0.18) or maximal vertical jump heights (F8,280=0.76; p=0.64). However, a trend was observed in which joint cooling immediately decreased (quarters 1 and 3) but active warm-up for approximately 20 min improved 20-min sprint times (quarters 2 and 4). Our study suggests that athletic performance such as sprinting and jumping are not altered by joint cooling applied prior to or during high-intensity intermittent exercise. © Georg Thieme Verlag KG Stuttgart · New York.

  17. Potential Universal Application of High-intensity Interval Training from Athletes and Sports Lovers to Patients.

    Science.gov (United States)

    Azuma, Koichiro; Matsumoto, Hideo

    2017-06-25

    Recently, high-intensity interval training (HIIT) has received much attention as a promising exercise option not only to improve aerobic fitness, but also to prevent and improve lifestyle-related diseases. Epidemiological studies have shown that the exercise volume, as determined by the product of exercise intensity, duration, and frequency, has been shown to be important for improvements in muscle mitochondrial activity and subsequent improvements in aerobic fitness, insulin sensitivity, and metabolic variables. Therefore, continuous moderate-intensity training has been widely recommended. On the other hand, the main contributor of HIIT to improvements in aerobic fitness and metabolic variables is its high-intensity nature, and many recent studies have shown results favoring HIIT when compared with conventional continuous training, despite its shorter exercise duration and smaller exercise volume. In this review, we aim to show the possible universal application of HIIT in a hospital setting, where athletes, sports lovers, and patients have sought medical advice and have the opportunity to undergo detailed evaluations, including an exercise stress test. For athletes, HIIT is mandatory to achieve further improvements in aerobic fitness. For patients, though higher levels of motivation and careful evaluation are required, the time constraints of HIIT are smaller and both aerobic and resistance training can be expected to yield favorable results because of the high-intensity nature of HIIT.

  18. High Temperature Boost (HTB) Power Processing Unit (PPU) Formulation Study

    Science.gov (United States)

    Chen, Yuan; Bradley, Arthur T.; Iannello, Christopher J.; Carr, Gregory A.; Mohammad, Mojarradi M.; Hunter, Don J.; DelCastillo, Linda; Stell, Christopher B.

    2013-01-01

    This technical memorandum is to summarize the Formulation Study conducted during fiscal year 2012 on the High Temperature Boost (HTB) Power Processing Unit (PPU). The effort is authorized and supported by the Game Changing Technology Division, NASA Office of the Chief Technologist. NASA center participation during the formulation includes LaRC, KSC and JPL. The Formulation Study continues into fiscal year 2013. The formulation study has focused on the power processing unit. The team has proposed a modular, power scalable, and new technology enabled High Temperature Boost (HTB) PPU, which has 5-10X improvement in PPU specific power/mass and over 30% in-space solar electric system mass saving.

  19. Orthodontics Align Crooked Teeth and Boost Self-Esteem

    Science.gov (United States)

    ... desktop! more... Orthodontics Align Crooked Teeth and Boost Self- esteem Article Chapters Orthodontics Align Crooked Teeth and Boost Self- esteem print full article print this chapter email this ...

  20. High-Intensity Interval Training in Normobaric Hypoxia Leads to Greater Body Fat Loss in Overweight/Obese Women than High-Intensity Interval Training in Normoxia

    Directory of Open Access Journals (Sweden)

    Alba Camacho-Cardenosa

    2018-02-01

    Full Text Available A moderate hypoxic stimulus is considered a promising therapeutic modality for several pathological states including obesity. There is scientific evidence suggesting that when hypoxia and physical activity are combined, they could provide benefits for the obese population. The aim of the present study was to investigate if exposure to hypoxia combined with two different protocols of high-intensity interval exercise in overweight/obese women was more effective compared with exercise in normoxia. Study participants included 82 overweight/obese women, who started a 12 week program of 36 sessions, and were randomly divided into four groups: (1 aerobic interval training in hypoxia (AitH; FiO2 = 17.2%; n = 13, (2 aerobic interval training in normoxia (AitN; n = 15, (3 sprint interval training in hypoxia (SitH; n = 15, and (4 sprint interval training in normoxia (SitN; n = 18. Body mass, body mass index, percentage of total fat mass, muscle mass, basal metabolic rate, fat, and carbohydrate oxidation, and fat and carbohydrate energy were assessed. Outcomes were measured at baseline (T1, after 18 training sessions (T2, 7 days after the last session (T3, and 4 weeks after the last session (T4. The fat mass in the SitH group was significantly reduced compared with the SitN group from T1 to T3 (p < 0.05 and from T1 to T4 (p < 0.05 and muscle mass increased significantly from T1 to T4 (p < 0.05. Fat mass in the AitH group decreased significantly (p < 0.01 and muscle mass increased (p = 0.022 compared with the AitN group from T1 to T4. All training groups showed a reduction in the percentage of fat mass, with a statistically significant reduction in the hypoxia groups (p < 0.05. Muscle mass increased significantly in the hypoxia groups (p < 0.05, especially at T4. While fat oxidation tended to increase and oxidation of carbohydrates tended to decrease in both hypoxia groups, the tendency was reversed in the normoxia groups. Thus, high-intensity interval

  1. Modeling of asymmetrical boost converters

    Directory of Open Access Journals (Sweden)

    Eliana Isabel Arango Zuluaga

    2014-01-01

    Full Text Available The asymmetrical interleaved dual boost (AIDB is a fifth-order DC/DC converter designed to interface photovoltaic (PV panels. The AIDB produces small current harmonics to the PV panels, reducing the power losses caused by the converter operation. Moreover, the AIDB provides a large voltage conversion ratio, which is required to step-up the PV voltage to the large dc-link voltage used in grid-connected inverters. To reject irradiance and load disturbances, the AIDB must be operated in a closed-loop and a dynamic model is required. Given that the AIDB converter operates in Discontinuous Conduction Mode (DCM, classical modeling approaches based on Continuous Conduction Mode (CCM are not valid. Moreover, classical DCM modeling techniques are not suitable for the AIDB converter. Therefore, this paper develops a novel mathematical model for the AIDB converter, which is suitable for control-pur-poses. The proposed model is based on the calculation of a diode current that is typically disregarded. Moreover, because the traditional correction to the second duty cycle reported in literature is not effective, a new equation is designed. The model accuracy is contrasted with circuital simulations in time and frequency domains, obtaining satisfactory results. Finally, the usefulness of the model in control applications is illustrated with an application example.

  2. Studies of Ion Acceleration from Thin Solid-Density Targets on High-Intensity Lasers

    Science.gov (United States)

    Willis, Christopher R.

    experiment utilized new liquid crystal film targets developed at OSU, which may be formed at variable thicknesses from tens of nanometers to several microns. On this experiment, an optimum ion energy and flux was reached for targets of 600-900 nm, providing a peak proton energy of 24 MeV, and total ion flux of > 109 protons over 3.4 MeV from 5.5 J of laser energy at an intensity of 1 x 1020 W cm -2. The primary ion diagnostics for these two experiments are described in detail, including the analysis techniques needed to extract absolutely calibrated spatial and spectral distributions of the accelerated ions. Additionally, a new technique for target alignment is presented, providing repeatable target alignment on the micron scale. This allows for a repeatable laser intensity on target, allowing improved shot to shot consistency on high intensity experiments. In addition to these two experiments, work on the upgrade and characterization of the 400 TW Scarlet laser is discussed, including several calculations critical to the design and upgrade of the laser system, as well as prepulse characterization needed for experiments on thin targets.

  3. CANCER Escape from senescence boosts tumour growth

    NARCIS (Netherlands)

    Medema, Jan Paul

    2018-01-01

    Some chemotherapies block cancer growth by driving tumour cells into a state of cell-division arrest termed senescence. It emerges that such cells have a boosted capacity to drive tumour growth if they exit senescence

  4. Boosting Learning Algorithm for Stock Price Forecasting

    Science.gov (United States)

    Wang, Chengzhang; Bai, Xiaoming

    2018-03-01

    To tackle complexity and uncertainty of stock market behavior, more studies have introduced machine learning algorithms to forecast stock price. ANN (artificial neural network) is one of the most successful and promising applications. We propose a boosting-ANN model in this paper to predict the stock close price. On the basis of boosting theory, multiple weak predicting machines, i.e. ANNs, are assembled to build a stronger predictor, i.e. boosting-ANN model. New error criteria of the weak studying machine and rules of weights updating are adopted in this study. We select technical factors from financial markets as forecasting input variables. Final results demonstrate the boosting-ANN model works better than other ones for stock price forecasting.

  5. Avoiding Anemia: Boost Your Red Blood Cells

    Science.gov (United States)

    ... Issues Subscribe January 2014 Print this issue Avoiding Anemia Boost Your Red Blood Cells En español Send ... Disease When Blood Cells Bend Wise Choices Preventing Anemia To prevent or treat iron-deficiency anemia: Eat ...

  6. Passive recovery is superior to active recovery during a high-intensity shock microcycle.

    Science.gov (United States)

    Wahl, Patrick; Zinner, Christoph; Grosskopf, Christoph; Rossmann, Roman; Bloch, Wilhelm; Mester, Joachim

    2013-05-01

    The purpose was to examine the effects of a 2-week high-intensity shock microcycle on maximal oxygen consumption and parameters of exercise performance in junior triathletes on the one hand and to evaluate the long-term effects of active (A) vs. passive (P) recovery on the other hand. Sixteen healthy junior triathletes participated in the study. For the assignment to the A or P group, the subjects were matched according to age and performance. Within 2 weeks, a total of 15 high-intensity interval sessions within three 3-day training blocks were performed. Before and 1 week after the last training session, the athletes performed a ramp test to determine V[Combining Dot Above]O2max, a time trial (TT) and a Wingate test. Furthermore, total hemoglobin (Hb) mass was determined. The results of the whole group, independent of the arrangement of recovery, were analyzed at first; second, the A and P groups were analyzed separately. Peak power output (PPO) during the ramp test and TT performance significantly increased in the whole group. The comparison of the 2 groups revealed increases for the mentioned parameters and for V[Combining Dot Above]O2 and power output at VT2 for the P group only. The V[Combining Dot Above]O2max did not change. Wingate performance increased in the A group only. The tHb mass slightly decreased. The main finding of this study was that a 14-day shock microcycle is able to improve TT performance and PPO in junior triathletes in a short period of time. Furthermore, not only the intensity but also the arrangement of interval training seems to be important as well, because only the P group showed improvements in endurance performance, despite a slightly lower training volume. These findings might be relevant for future arrangements of high-intensity interval training.

  7. Effect of caffeine ingestion after creatine supplementation on intermittent high-intensity sprint performance.

    Science.gov (United States)

    Lee, Chia-Lun; Lin, Jung-Charng; Cheng, Ching-Feng

    2011-08-01

    The aim of this study was to investigate the effects of acute caffeine ingestion on intermittent high-intensity sprint performance after 5 days of creatine loading. After completing a control trial (no ergogenic aids, CON), twelve physically active men were administered in a double-blind, randomized crossover protocol to receive CRE + PLA (0.3 g kg(-1) day(-1) of creatine for 5 days then followed by 6 mg kg(-1) of placebo) and CRE + CAF (0.3 g kg(-1) day(-1) of creatine for 5 days and followed by 6 mg kg(-1) of caffeine), after which they performed a repeated sprint test. Each test consisted of six 10-s intermittent high-intensity sprints on a cycling ergometer, with 60-s rest intervals between sprints. Mean power, peak power, rating of perceived exertion (RPE), and heart rates were measured during the test. Blood samples for lactate, glucose, and catecholamine concentrations were drawn at specified intervals. The mean and peak power observed in the CRE + CAF were significantly higher than those found in the CON during Sprints 1 and 3; and the CRE + CAF showed significantly higher mean and peak power than that in the CRE + PLA during Sprints 1 and 2. The mean and peak power during Sprint 3 in the CRE + PLA was significantly greater than that in the CON. Heart rates, plasma lactate, and glucose increased significantly with CRE + CAF during most sprints. No significant differences were observed in the RPE among the three trials. The present study determined that caffeine ingestion after creatine supplements augmented intermittent high-intensity sprint performance.

  8. ARRONAX, a high-energy and high-intensity cyclotron for nuclear medicine

    International Nuclear Information System (INIS)

    Haddad, Ferid; Guertin, Arnaud; Michel, Nathalie; Ferrer, Ludovic; Carlier, Thomas; Barbet, Jacques; Chatal, Jean-Francois

    2008-01-01

    This study was aimed at establishing a list of radionuclides of interest for nuclear medicine that can be produced in a high-intensity and high-energy cyclotron. We have considered both therapeutic and positron emission tomography radionuclides that can be produced using a high-energy and a high-intensity cyclotron such as ARRONAX, which will be operating in Nantes (France) by the end of 2008. Novel radionuclides or radionuclides of current limited availability have been selected according to the following criteria: emission of positrons, low-energy beta or alpha particles, stable or short half-life daughters, half-life between 3 h and 10 days or generator-produced, favourable dosimetry, production from stable isotopes with reasonable cross sections. Three radionuclides appear well suited to targeted radionuclide therapy using beta ( 67 Cu, 47 Sc) or alpha ( 211 At) particles. Positron emitters allowing dosimetry studies prior to radionuclide therapy ( 64 Cu, 124 I, 44 Sc), or that can be generator-produced ( 82 Rb, 68 Ga) or providing the opportunity of a new imaging modality ( 44 Sc) are considered to have a great interest at short term whereas 86 Y, 52 Fe, 55 Co, 76 Br or 89 Zr are considered to have a potential interest at middle term. Several radionuclides not currently used in routine nuclear medicine or not available in sufficient amount for clinical research have been selected for future production. High-energy, high-intensity cyclotrons are necessary to produce some of the selected radionuclides and make possible future clinical developments in nuclear medicine. Associated with appropriate carriers, these radionuclides will respond to a maximum of unmet clinical needs. (orig.) 5

  9. ARRONAX, a high-energy and high-intensity cyclotron for nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    Haddad, Ferid; Guertin, Arnaud; Michel, Nathalie [SUBATECH, Universite de Nantes, Ecole des Mines de Nantes, CNRS/IN2P3, La Chantrerie, 4, rue A. Kastler, BP 20722, Nantes (France); Ferrer, Ludovic [Universite de Nantes, Departement de Recherche en Cancerologie, Inserm, Nantes (France); Rene Gauducheau Cancer Center, Nantes (France); Carlier, Thomas; Barbet, Jacques; Chatal, Jean-Francois [Universite de Nantes, Departement de Recherche en Cancerologie, Inserm, Nantes (France)

    2008-07-15

    This study was aimed at establishing a list of radionuclides of interest for nuclear medicine that can be produced in a high-intensity and high-energy cyclotron. We have considered both therapeutic and positron emission tomography radionuclides that can be produced using a high-energy and a high-intensity cyclotron such as ARRONAX, which will be operating in Nantes (France) by the end of 2008. Novel radionuclides or radionuclides of current limited availability have been selected according to the following criteria: emission of positrons, low-energy beta or alpha particles, stable or short half-life daughters, half-life between 3 h and 10 days or generator-produced, favourable dosimetry, production from stable isotopes with reasonable cross sections. Three radionuclides appear well suited to targeted radionuclide therapy using beta ({sup 67}Cu, {sup 47}Sc) or alpha ({sup 211}At) particles. Positron emitters allowing dosimetry studies prior to radionuclide therapy ({sup 64}Cu, {sup 124}I, {sup 44}Sc), or that can be generator-produced ({sup 82}Rb, {sup 68}Ga) or providing the opportunity of a new imaging modality ({sup 44}Sc) are considered to have a great interest at short term whereas {sup 86}Y, {sup 52}Fe, {sup 55}Co, {sup 76}Br or {sup 89}Zr are considered to have a potential interest at middle term. Several radionuclides not currently used in routine nuclear medicine or not available in sufficient amount for clinical research have been selected for future production. High-energy, high-intensity cyclotrons are necessary to produce some of the selected radionuclides and make possible future clinical developments in nuclear medicine. Associated with appropriate carriers, these radionuclides will respond to a maximum of unmet clinical needs. (orig.)

  10. ARRONAX, a high-energy and high-intensity cyclotron for nuclear medicine.

    Science.gov (United States)

    Haddad, Ferid; Ferrer, Ludovic; Guertin, Arnaud; Carlier, Thomas; Michel, Nathalie; Barbet, Jacques; Chatal, Jean-François

    2008-07-01

    This study was aimed at establishing a list of radionuclides of interest for nuclear medicine that can be produced in a high-intensity and high-energy cyclotron. We have considered both therapeutic and positron emission tomography radionuclides that can be produced using a high-energy and a high-intensity cyclotron such as ARRONAX, which will be operating in Nantes (France) by the end of 2008. Novel radionuclides or radionuclides of current limited availability have been selected according to the following criteria: emission of positrons, low-energy beta or alpha particles, stable or short half-life daughters, half-life between 3 h and 10 days or generator-produced, favourable dosimetry, production from stable isotopes with reasonable cross sections. Three radionuclides appear well suited to targeted radionuclide therapy using beta ((67)Cu, (47)Sc) or alpha ((211)At) particles. Positron emitters allowing dosimetry studies prior to radionuclide therapy ((64)Cu, (124)I, (44)Sc), or that can be generator-produced ((82)Rb, (68)Ga) or providing the opportunity of a new imaging modality ((44)Sc) are considered to have a great interest at short term whereas (86)Y, (52)Fe, (55)Co, (76)Br or (89)Zr are considered to have a potential interest at middle term. Several radionuclides not currently used in routine nuclear medicine or not available in sufficient amount for clinical research have been selected for future production. High-energy, high-intensity cyclotrons are necessary to produce some of the selected radionuclides and make possible future clinical developments in nuclear medicine. Associated with appropriate carriers, these radionuclides will respond to a maximum of unmet clinical needs.

  11. Locomotor muscle fatigue does not alter oxygen uptake kinetics during high-intensity exercise

    Directory of Open Access Journals (Sweden)

    James Hopker

    2016-10-01

    Full Text Available The slow component (VO2sc that develops during high-intensity aerobic exercise is thought to be strongly associated with locomotor muscle fatigue. We sought to experimentally test this hypothesis by pre-fatiguing the locomotor muscles used during subsequent high-intensity cycling exercise. Over two separate visits, eight healthy male participants were asked to either perform a non-metabolically stressful 100 intermittent drop-jumps protocol (pre fatigue condition or rest for 33 minutes (control condition according to a random and counterbalanced order. Locomotor muscle fatigue was quantified with 6-second maximal sprints at a fixed pedaling cadence of 90 rev·min-1. Oxygen kinetics and other responses (heart rate, capillary blood lactate concentration and rating of perceived exertion, RPE were measured during two subsequent bouts of 6 min cycling exercise at 50% of the delta between the lactate threshold and VO2max determined during a preliminary incremental exercise test. All tests were performed on the same cycle ergometer. Despite significant locomotor muscle fatigue (P = 0.03, the VO2sc was not significantly different between the pre fatigue (464 ± 301 mL·min-1 and the control (556 ± 223 mL·min-1 condition (P = 0.50. Blood lactate response was not significantly different between conditions (P = 0.48 but RPE was significantly higher following the pre-fatiguing exercise protocol compared with the control condition (P < 0.01 suggesting higher muscle recruitment. These results demonstrate experimentally that locomotor muscle fatigue does not significantly alter the VO2 kinetic response to high intensity aerobic exercise, and challenge the hypothesis that the VO2sc is strongly associated with locomotor muscle fatigue.

  12. Effect of high-intensity statin therapy on atherosclerosis in non-infarct-related coronary arteries (IBIS-4)

    DEFF Research Database (Denmark)

    Räber, Lorenz; Taniwaki, Masanori; Zaugg, Serge

    2015-01-01

    AIM: The effect of long-term high-intensity statin therapy on coronary atherosclerosis among patients with acute ST-segment elevation myocardial infarction (STEMI) is unknown. The aim of this study was to quantify the impact of high-intensity statin therapy on plaque burden, composition, and phen......AIM: The effect of long-term high-intensity statin therapy on coronary atherosclerosis among patients with acute ST-segment elevation myocardial infarction (STEMI) is unknown. The aim of this study was to quantify the impact of high-intensity statin therapy on plaque burden, composition......, P = 0.15). CONCLUSION: High-intensity rosuvastatin therapy over 13 months is associated with regression of coronary atherosclerosis in non-infarct-related arteries without changes in RF-IVUS defined necrotic core or plaque phenotype among STEMI patients....

  13. Top reconstruction and boosted top experimental overview

    CERN Document Server

    Skinnari, Louise

    2015-01-01

    An overview of techniques used to reconstruct resolved and boosted top quarks is presented. Techniques for resolved top quark reconstruction include kinematic likelihood fitters and pseudo- top reconstruction. Many tools and methods are available for the reconstruction of boosted top quarks, such as jet grooming techniques, jet substructure variables, and dedicated top taggers. Different techniques as used by ATLAS and CMS analyses are described and the performance of different variables and top taggers are shown.

  14. Surface hardness monitoring of cement during curing by high-intensity aerial ultrasonic waves

    Science.gov (United States)

    Fujiwara, Hajime; Osumi, Ayumu; Ito, Youichi

    2017-07-01

    We propose a method for monitoring the surface hardness of cement during curing by using high-intensity aerial ultrasonic waves and optical equipment. Our method estimates the progress of curing from the vibrations generated on the object surface by aerial ultrasonic wave irradiation. We monitored cement curing from a liquid state immediately after placement in real time and investigated a method for decreasing the dispersion of the measured values. As a result, we demonstrated that cement could be monitored from the liquid state to the solid state after placement. In addition, we confirmed that the effects of various external factors were avoided by using median measurement values.

  15. Design concept of radiation control system for the high intensity proton accelerator facility

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, Yukihiro; Ikeno, Koichi; Akiyama, Shigenori; Harada, Yasunori [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2002-11-01

    Description is given for the characteristic radiation environment for the High Intensity Proton Accelerator Facility and the design concept of the radiation control system of it. The facility is a large scale accelerator complex consisting of high energy proton accelerators carrying the highest beam intensity in the world and the related experimental facilities and therefore provides various issues relevant to the radiation environment. The present report describes the specifications for the radiation control system for the facility, determined in consideration of these characteristics. (author)

  16. No effect of glycogen level on glycogen metabolism during high intensity exercise

    DEFF Research Database (Denmark)

    Vandenberghe, Katleen; Hespel, P.; Eynde, Bart Vanden

    1995-01-01

    This study examined the effect of glycogen supercompensation on glycogen breakdown, muscle and blood lactate accumulation, blood-pH, and performance during short-term high-intensity exercise. Young healthy volunteers performed two supramaximal (125% of VO2max) exercise tests on a bicycle ergometer...... and blood-lactate, and the fall in blood-pH were similar during N and CHR. In protocol 2, time to exhaustion was identical for N and CHR. It is concluded that during short-term intense exercise during which muscle glycogen availability exceeds glycogen demand, rate of glycogen breakdown, lactate...

  17. The 1989 progress report: Laboratory for the Utilization of High-Intensity Laser

    International Nuclear Information System (INIS)

    Fabre, E.

    1989-01-01

    The 1989 progress report of the laboratory for the Utilization of High-Intensity Lasers of the Polytechnic School (France) is presented. The investigations reported were performed in the following fields: laser-matter interactions in fusion experiments, particles' laser acceleration, picoseconds and femtoseconds interactions, low-flux interactions, development of hydrodynamic codes, laser chocks simulation codes, x-ray lasers, generation of high pressures, implosion physics at 0.26 microns, dense plasmas, material's hardening by laser radiation. The published papers, the conferences and the Laboratory staff are listed [fr

  18. Effect of moderate- and high-intensity acute exercise on appetite in obese individuals

    DEFF Research Database (Denmark)

    Martins, Catia; Stensvold, Dorthe; Finlayson, Graham

    2015-01-01

    PURPOSE: The effect of acute exercise, and exercise intensity, on appetite control in obese individuals requires further study. The aim of this study was to compare the effects of acute isocaloric bouts (250 kcal) of high-intensity intermittent cycling (HIIC) and moderate-intensity continuous....../obese volunteers. Participants were assigned to the control, MICC, HIIC, and S-HIIC conditions, 1 wk apart, in a counterbalanced order. Exercise was performed 1 h after a standard breakfast. An ad libitum test lunch was served 3 h after breakfast. Fasting/postprandial plasma samples of insulin, acylated ghrelin...

  19. The Effect of High-Intensity Intermittent Exercise on Body Composition of Overweight Young Males

    Directory of Open Access Journals (Sweden)

    M. Heydari

    2012-01-01

    Full Text Available To determine the effect of a 12-week high intensity intermittent exercise (HIIE intervention on total body, abdominal, trunk, visceral fat mass, and fat free mass of young overweight males. Participants were randomly assigned to either exercise or control group. The intervention group received HIIE three times per week, 20 min per session, for 12 weeks. Aerobic power improved significantly (P0.05 occurred in levels of insulin, HOMA-IR, and blood lipids. Twelve weeks of HIIE resulted in significant reductions in total, abdominal, trunk, and visceral fat and significant increases in fat free mass and aerobic power.

  20. High-Intensity Training Improves Exercise Performance in Elite Women Volleyball Players During a Competitive Season.

    Science.gov (United States)

    Purkhús, Elisabeth; Krustrup, Peter; Mohr, Magni

    2016-11-01

    Purkhús, E, Krustrup, P, and Mohr, M. High-intensity training improves exercise performance in elite women volleyball players during a competitive season. J Strength Cond Res 30(11): 3066-3072, 2016-Elite women volleyball players (n = 25; mean ± SD: age, 19 ± 5 years; height, 171 ± 7 cm; weight, 63 ± 10 kg) volunteered to participate in the study. They were randomized into a high-intensity training (HIT; n = 13) group and a control (CON; n = 12) group. In addition to the normal team training and games, HIT performed 6-10 × 30-seconds all-out running intervals separated by 3-minute recovery periods 3 times per week during a 4-week in-season period whereas CON only completed the team training sessions and games. Preintervention and postintervention, all players completed the arrowhead agility test (AAT), a repeated sprint test (RST; 5 × 30 meters separated by 25 seconds of recovery), and the Yo-Yo Intermittent Recovery level 2 test (Yo-Yo IR2) followed by a-10 minute rest period and the Yo-Yo IR1 test. Mean running distance during HIT in week 1 was 152 ± 4 m and increased (p ≤ 0.05) by 4.6% (159 ± 3 m) in week 4. The AAT performance improved (p ≤ 0.05) by 2.3% (18.87 ± 0.97-18.44 ± 1.06 seconds) and RST by 4.3% postintervention in the HIT group only. Baseline RST fatigue index was 7.0 ± 2.9 and 6.2 ± 5.0% in HIT and CON, respectively, but was lowered (p ≤ 0.05) to 2.7 ± 3.0% posttraining in HIT and remained unaltered in CON (5.5 ± 5.0%). In HIT, Yo-Yo IR2 and Yo-Yo IR1 performance improved by 12.6 and 18.3% postintervention, respectively, with greater (p ≤ 0.05) Yo-yo IR1 change scores than in CON. In conclusion, additional high-intensity in-season training performed as interval running improved agility, repeated sprint ability, and high-intensity intermittent exercise performance in elite women volleyball players.

  1. The development and applications of sucralose, a new high-intensity sweetener.

    Science.gov (United States)

    Knight, I

    1994-04-01

    Sucralose is a new sweetener discovered during a collaborative research program between Tate & Lyle and Queen Elizabeth College of the University of London. It is made by selective substitution of sucrose hydroxyl groups by chlorine, resulting in a highly intense (600x) sugarlike sweetness and exceptional stability at both high temperature and low pH. The research leading to the discovery of sweetness in differently halogenated sucrose is described, as well as the development of sucralose and the process of safety testing and government approval. Finally, sucralose properties and applications in Canada's food and beverage industries are discussed.

  2. Continuous Exercise but Not High Intensity Interval Training Improves Fat Distribution in Overweight Adults

    Science.gov (United States)

    Keating, Shelley E.; Machan, Elizabeth A.; O'Connor, Helen T.; Gerofi, James A.; Sainsbury, Amanda; Caterson, Ian D.; Johnson, Nathan A.

    2014-01-01

    Objective. The purpose of this study was to assess the effect of high intensity interval training (HIIT) versus continuous aerobic exercise training (CONT) or placebo (PLA) on body composition by randomized controlled design. Methods. Work capacity and body composition (dual-energy X-ray absorptiometry) were measured before and after 12 weeks of intervention in 38 previously inactive overweight adults. Results. There was a significant group × time interaction for change in work capacity (P exercise in inactive, overweight adults. However, in this population HIIT does not confer the same benefit to body fat levels as continuous exercise training. PMID:24669314

  3. High-intensity interval training improves insulin sensitivity in older individuals

    DEFF Research Database (Denmark)

    Søgaard, D; Lund, M T; Scheuer, C M

    2017-01-01

    AIM: Metabolic health may deteriorate with age as a result of altered body composition and decreased physical activity. Endurance exercise is known to counter these changes delaying or even preventing onset of metabolic diseases. High-intensity interval training (HIIT) is a time efficient...... HIIT session consisted of five 1-minute intervals interspersed with 1½-minute rest. Prior to the first and after the last HIIT session whole-body insulin sensitivity, measured by a hyperinsulinaemic-euglycaemic clamp, plasma lipid levels, HbA1c, glycaemic parameters, body composition and maximal oxygen......-density lipoprotein (P body fat (P

  4. A data acquisition system for a high intensity powder diffractometer at HANARO

    International Nuclear Information System (INIS)

    Cheon, Jong-Kyu; Moon, Myung-Kook; Lee, Chang-Hee; Em, V. T; Lee, Seong-Su; Nam, Uk-Won; Yi, Jung-Hwan; Park, Je-Geun; Kim, Hong-Ju

    2010-01-01

    A data acquisition (DAQ) and control system for the high intensity powder diffractometer (HIPD) at High-flux Advanced Neutron Application ReactOr (HANARO) is developed in this paper. The HIPD provides the advantage of wide-angle coverage of neutron diffraction operations, which can reduce the time that is required for experiments. The HIPD DAQ and control system was commissioned into operation and the diffraction data of Al 2 O 3 was recorded successfully. The details of the detector, the data acquisition process and the instrument controls system used in the operation of the HIPD are presented.

  5. Analysis of a high intensity shear zone between overlapping fiber ends in a polymer matrix composite

    DEFF Research Database (Denmark)

    Lindgreen, Britta

    2008-01-01

    The formation of high intensity shear zones in a glass fiber reinforced thermoplast is studied numerically. The thermoplast is characterized by a finite strain elastic-viscoplastic constitutive relation and the calculations are carried out using a dynamic finite element program where plane strain...... that develop as the highly deformed region approaches the limit resulting from network stiffening in the polymer. A simple analysis assuming periodicity is included in order to study the mechanical behaviour of the polymer matrix between fiber ends with long overlap....

  6. Discussion of superconducting and room-temperature high-intensity ion linacs

    International Nuclear Information System (INIS)

    Jameson, R.A.

    1996-01-01

    The point of view taken in this discussion is that the basic technology base exists in all essential respects for both superconducting or room-temperature rf linac accelerators and associated power and control systems, and thus a project can make a choice between these technologies on overall system considerations. These include performance, cost, availability, flexibility, and upgradability. Large high-intensity neutron source proposals involving light-ion rf linacs in three categories are reviewed in this context. The categories arc cw linacs to high (∼1 GeV) and low (∼40 MeV) output energy, and pulsed linacs to energy ∼1 GeV

  7. Effects and sustainability of a 13-day high-intensity shock microcycle in soccer.

    Science.gov (United States)

    Wahl, Patrick; Güldner, Matthias; Mester, Joachim

    2014-05-01

    The preseason in soccer is a short period of 6-8 weeks where conditional abilities, technical and tactical elements need to be trained. Therefore, time is lacking to perform long term preparation periods for different abilities, especially endurance training. There is evidence that the implementation of high-intensity shock microcycles in preseason training could be one way to improve physical performance in a short period of time. Therefore, the purpose of the present study was to examine the effects and the sustainability of a high-intensity shock microcycle on soccer specific performance. Over 2 weeks, 12 male soccer players (26.1 ± 4.5 years) performed 12 high-intensity training (HIT) sessions in addition to their usual training. Before (pre), 6 days (6d) and 25 days (25d) after training, subjects performed Counter Movement Jump (CMJ), Repeated-Sprint Ability (RSA) test and Yo-Yo Intermittent Recovery Test Level 2 (YYIR2). Mean sprint time (RSAMean) (cohen's d = -1.15), percentage decrement score (RSAIndex) (cohen's d = -1.99) and YYIR2 (cohen's d = +1.92) improved significantly from pre to 6d. 25d after, values showed a significant reduction for YYIR2 (cohen's d = -0.81) and small to moderate but not significant increase for RSAMean (cohen's d = +0.37) and RSAIndex (cohen's d = +0.7) compared to 6d values. Small but no significant increases were found for CMJ (cohen's d = +0.33) and no significant and substantial changes were found for RSABest (cohen's d = -0.07) from pre to 6d. For competitive soccer players, block periodization of HIT offers a promising way to largely improve RSA and YYIR2 in a short period of time. Despite moderate to large decreases in RSAIndex and YYIR2 performance in the 19 day period without HIT, values still remained significantly higher 25d after the last HIT session compared to pre-values. However, it might be necessary to include isolated high-intensity sessions after a HIT training block in order to maintain the higher level of

  8. Effects and Sustainability of a 13-Day High-Intensity Shock Microcycle in Soccer

    Directory of Open Access Journals (Sweden)

    Patrick Wahl

    2014-06-01

    Full Text Available The preseason in soccer is a short period of 6-8 weeks where conditional abilities, technical and tactical elements need to be trained. Therefore, time is lacking to perform long term preparation periods for different abilities, especially endurance training. There is evidence that the implementation of high-intensity shock microcycles in preseason training could be one way to improve physical performance in a short period of time. Therefore, the purpose of the present study was to examine the effects and the sustainability of a high-intensity shock microcycle on soccer specific performance. Over 2 weeks, 12 male soccer players (26.1 ± 4.5 years performed 12 high-intensity training (HIT sessions in addition to their usual training. Before (pre, 6 days (6d and 25 days (25d after training, subjects performed Counter Movement Jump (CMJ, Repeated-Sprint Ability (RSA test and Yo-Yo Intermittent Recovery Test Level 2 (YYIR2. Mean sprint time (RSAMean (cohen’s d = -1.15, percentage decrement score (RSAIndex (cohen’s d = -1.99 and YYIR2 (cohen’s d = +1.92 improved significantly from pre to 6d. 25d after, values showed a significant reduction for YYIR2 (cohen’s d = -0.81 and small to moderate but not significant increase for RSAMean (cohen’s d = +0.37 and RSAIndex (cohen’s d = +0.7 compared to 6d values. Small but no significant increases were found for CMJ (cohen’s d = +0.33 and no significant and substantial changes were found for RSABest (cohen’s d = -0.07 from pre to 6d. For competitive soccer players, block periodization of HIT offers a promising way to largely improve RSA and YYIR2 in a short period of time. Despite moderate to large decreases in RSAIndex and YYIR2 performance in the 19 day period without HIT, values still remained significantly higher 25d after the last HIT session compared to pre-values. However, it might be necessary to include isolated high-intensity sessions after a HIT training block in order to maintain the

  9. High intensity compact Compton X-ray sources: Challenges and potential of applications

    Energy Technology Data Exchange (ETDEWEB)

    Jacquet, M., E-mail: mjacquet@lal.in2p3.fr

    2014-07-15

    Thanks to the exceptional development of high power femtosecond lasers in the last 15 years, Compton based X-ray sources are in full development over the world in the recent years. Compact Compton sources are able to combine the compactness of the instrument with a beam of high intensity, high quality, tunable in energy. In various fields of applications such as biomedical science, cultural heritage preservation and material science researches, these sources should provide an easy working environment and the methods currently used at synchrotrons could be largely developed in a lab-size environment as hospitals, labs, or museums.

  10. Potency of high-intensity ultrasonic treatment for grain refinement of magnesium alloys

    International Nuclear Information System (INIS)

    Ramirez, A.; Qian Ma; Davis, B.; Wilks, T.; StJohn, D.H.

    2008-01-01

    High-intensity ultrasonic treatment (UT) for grain refinement of magnesium alloys has been investigated using a novel theoretical approach in order to better understand its grain-refining potential and the mechanism of nucleation. The process demonstrated significantly superior grain-refining potency to carbon inoculation for Al-containing magnesium alloys but inferior potency to zirconium for Al-free alloys. Details revealed by applying the theoretical approach to ultrasonic grain refinement provide new clues to understanding the mechanism of grain nucleation by UT

  11. Target surface area effects on hot electron dynamics from high intensity laser-plasma interactions

    Science.gov (United States)

    Zulick, C.; Raymond, A.; McKelvey, A.; Chvykov, V.; Maksimchuk, A.; Thomas, A. G. R.; Willingale, L.; Yanovsky, V.; Krushelnick, K.

    2016-06-01

    Reduced surface area targets were studied using an ultra-high intensity femtosecond laser in order to determine the effect of electron sheath field confinement on electron dynamics. X-ray emission due to energetic electrons was imaged using a {K}α imaging crystal. Electrons were observed to travel along the surface of wire targets, and were slowed mainly by the induced fields. Targets with reduced surface areas were correlated with increased hot electron densities and proton energies. Hybrid Vlasov-Fokker-Planck simulations demonstrated increased electric sheath field strength in reduced surface area targets.

  12. New initiatives on lepton flavor violation and neutrino oscillation with high intense muon and neutrino sources

    CERN Document Server

    Kuno, Yoshitaka; Pakvasa, Sandip

    2002-01-01

    The area of physics involving muons and neutrinos has become exciting in particle physics. Using their high intensity sources, physicists undertake, in various ways, extensive searches for new physics beyond the Standard Model, such as tests of supersymmetric grand unification (SUSY-GUT) and precision measurements of the muon and neutrino properties, which will in future extend to ambitious studies such as determination of the three-generation neutrino mixing matrix elements and CP violation in the lepton sector. The physics of this field is advancing, with potential improvements of the source

  13. The influence of basketball dribbling on repeated high-intensity intermittent runs

    OpenAIRE

    Zhaowei Kong; Fengxue Qi; Qingde Shi

    2015-01-01

    Background/Objective: This research examines whether or not the Yo-Yo testing performance could reflect the repeatability of high-intensity intermittent dribbling in adolescent basketball players. Methods: Thirty-six teenage basketball players aged 13–18 years were invited to participate in this study. Results: A test–retest showed that the Yo-Yo intermittent endurance Level 2 (IE2) test with dribbling (intraclass correlation coefficient = 0.92; coefficient of variation = 12.6%; d = 0.2...

  14. Physiological responses of young thoroughbred horses to intermittent high-intensity treadmill training.

    Science.gov (United States)

    Ohmura, Hajime; Matsui, Akira; Hada, Tetsuro; Jones, James H

    2013-08-17

    Training of young Thoroughbred horses must balance development of cardiopulmonary function and aerobic capacity with loading of the musculoskeletal system that can potentially cause structural damage and/or lameness. High-speed equine treadmills are sometimes used to supplement exercise on a track in the training of young Thoroughbreds because the horse can run at high speeds but without the added weight of a rider. We tested the hypothesis that intermittent high-intensity exercise on a treadmill of young Thoroughbred horses entering training can enhance development of aerobic capacity (VO2max) and running performance more than conventional training under saddle, and do so without causing lameness. Twelve yearling Thoroughbreds trained for 8 months with conventional riding (C) only, conventional riding plus a short (2 month, S) interval of once-per-week high-intensity treadmill exercise, or a long (8 month, L) interval of once-per-week high-intensity treadmill exercise. Three treadmill exercise tests evaluated VO2max, oxygen transport and running performance variables in June of the yearling year (only for L), October of the yearling year and April of the 2-year-old year. No horses experienced lameness during the study. Aerobic capacity increased in all groups after training. In both October and April, VO2max in L was higher than in C, but did not differ between L and S or S and C. Running speeds eliciting VO2max also increased in all groups after training, with S (809±3 m/s) and L (804±9 m/s) higher than C (764±27 m/s). Maximum heart rate decreased for all groups after training. Hematocrit and hemoglobin concentration increased for L throughout training. Young Thoroughbred horses can increase aerobic capacity and running performance more than by strictly using track training under saddle with the addition of intermittent high-intensity treadmill exercise, and they can do so without experiencing lameness. This finding suggests that young racehorses might be able

  15. Stereotactic Body Radiation Therapy Boost in Locally Advanced Pancreatic Cancer

    International Nuclear Information System (INIS)

    Seo, Young Seok; Kim, Mi-Sook; Yoo, Sung Yul; Cho, Chul Koo; Yang, Kwang Mo; Yoo, Hyung Jun; Choi, Chul Won; Lee, Dong Han; Kim, Jin; Kim, Min Suk; Kang, Hye Jin; Kim, YoungHan

    2009-01-01

    Purpose: To investigate the clinical application of a stereotactic body radiation therapy (SBRT) boost in locally advanced pancreatic cancer patients with a focus on local efficacy and toxicity. Methods and Materials: We retrospectively reviewed 30 patients with locally advanced and nonmetastatic pancreatic cancer who had been treated between 2004 and 2006. Follow-up duration ranged from 4 to 41 months (median, 14.5 months). A total dose of 40 Gy was delivered in 20 fractions using a conventional three-field technique, and then a single fraction of 14, 15, 16, or 17 Gy SBRT was administered as a boost without a break. Twenty-one patients received chemotherapy. Overall and local progression-free survival were calculated and prognostic factors were evaluated. Results: One-year overall survival and local progression-free survival rates were 60.0% and 70.2%, respectively. One patient (3%) developed Grade 4 toxicity. Carbohydrate antigen 19-9 response was found to be an independent prognostic factor for survival. Conclusions: Our findings indicate that a SBRT boost provides a safe means of increasing radiation dose. Based on the results of this study, we recommend that a well controlled Phase II study be conducted on locally advanced pancreatic cancer.

  16. Boosted dark matter signals uplifted with self-interaction

    Energy Technology Data Exchange (ETDEWEB)

    Kong, Kyoungchul, E-mail: kckong@ku.edu [Department of Physics and Astronomy, University of Kansas, Lawrence, KS 66045 (United States); Mohlabeng, Gopolang, E-mail: mohlabeng319@gmail.com [Department of Physics and Astronomy, University of Kansas, Lawrence, KS 66045 (United States); Park, Jong-Chul, E-mail: log1079@gmail.com [Department of Physics and Astronomy, University of Kansas, Lawrence, KS 66045 (United States); Department of Physics, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2015-04-09

    We explore detection prospects of a non-standard dark sector in the context of boosted dark matter. We focus on a scenario with two dark matter particles of a large mass difference, where the heavier candidate is secluded and interacts with the standard model particles only at loops, escaping existing direct and indirect detection bounds. Yet its pair annihilation in the galactic center or in the Sun may produce boosted stable particles, which could be detected as visible Cherenkov light in large volume neutrino detectors. In such models with multiple candidates, self-interaction of dark matter particles is naturally utilized in the assisted freeze-out mechanism and is corroborated by various cosmological studies such as N-body simulations of structure formation, observations of dwarf galaxies, and the small scale problem. We show that self-interaction of the secluded (heavier) dark matter greatly enhances the capture rate in the Sun and results in promising signals at current and future experiments. We perform a detailed analysis of the boosted dark matter events for Super-Kamiokande, Hyper-Kamiokande and PINGU, including notable effects such as evaporation due to self-interaction and energy loss in the Sun.

  17. Boosted dark matter signals uplifted with self-interaction

    Directory of Open Access Journals (Sweden)

    Kyoungchul Kong

    2015-04-01

    Full Text Available We explore detection prospects of a non-standard dark sector in the context of boosted dark matter. We focus on a scenario with two dark matter particles of a large mass difference, where the heavier candidate is secluded and interacts with the standard model particles only at loops, escaping existing direct and indirect detection bounds. Yet its pair annihilation in the galactic center or in the Sun may produce boosted stable particles, which could be detected as visible Cherenkov light in large volume neutrino detectors. In such models with multiple candidates, self-interaction of dark matter particles is naturally utilized in the assisted freeze-out mechanism and is corroborated by various cosmological studies such as N-body simulations of structure formation, observations of dwarf galaxies, and the small scale problem. We show that self-interaction of the secluded (heavier dark matter greatly enhances the capture rate in the Sun and results in promising signals at current and future experiments. We perform a detailed analysis of the boosted dark matter events for Super-Kamiokande, Hyper-Kamiokande and PINGU, including notable effects such as evaporation due to self-interaction and energy loss in the Sun.

  18. High-Intensity Interval Training in Normobaric Hypoxia Leads to Greater Body Fat Loss in Overweight/Obese Women than High-Intensity Interval Training in Normoxia.

    Science.gov (United States)

    Camacho-Cardenosa, Alba; Camacho-Cardenosa, Marta; Burtscher, Martin; Martínez-Guardado, Ismael; Timon, Rafael; Brazo-Sayavera, Javier; Olcina, Guillermo

    2018-01-01

    A moderate hypoxic stimulus is considered a promising therapeutic modality for several pathological states including obesity. There is scientific evidence suggesting that when hypoxia and physical activity are combined, they could provide benefits for the obese population. The aim of the present study was to investigate if exposure to hypoxia combined with two different protocols of high-intensity interval exercise in overweight/obese women was more effective compared with exercise in normoxia. Study participants included 82 overweight/obese women, who started a 12 week program of 36 sessions, and were randomly divided into four groups: (1) aerobic interval training in hypoxia (AitH; FiO 2 = 17.2%; n = 13), (2) aerobic interval training in normoxia (AitN; n = 15), (3) sprint interval training in hypoxia (SitH; n = 15), and (4) sprint interval training in normoxia (SitN; n = 18). Body mass, body mass index, percentage of total fat mass, muscle mass, basal metabolic rate, fat, and carbohydrate oxidation, and fat and carbohydrate energy were assessed. Outcomes were measured at baseline (T1), after 18 training sessions (T2), 7 days after the last session (T3), and 4 weeks after the last session (T4). The fat mass in the SitH group was significantly reduced compared with the SitN group from T1 to T3 ( p training groups showed a reduction in the percentage of fat mass, with a statistically significant reduction in the hypoxia groups ( p interval training under normobaric intermittent hypoxia for 12 weeks in overweight/obese women seems to be promising for reducing body fat content with a concomitant increase in muscle mass.

  19. HILL: The High-Intensity Laser Laboratory Core Team's Reply to Questions from the NNSA Experimental Facilities Panel

    International Nuclear Information System (INIS)

    Albright, B.J.

    2012-01-01

    Question 1 - The type of physics regimes that HILL can access for weapons studies is quite interesting. The question that arises for the proposal team is what priority does this type of experimental data have versus data that can be obtained with NIF, and Z. How does HILL rank in priority compared to MARIE 1.0 in terms of the experimental data it will provide? We reiterate that isochoric heating experiments to be conducted with HILL are complementary to the high energy density physics experiments at NIF and Z and uniquely access states of matter that neither other facility can access. It is our belief that HILL will enable several important questions, e.g., as related to mix morphology, radiation transfer from corrugated surfaces, and equations of state, to be run to ground through carefully diagnosed, 'unit-physics' experiments. Such experiments will substantially improve confidence in our computer models and provide a rigorous science basis for certification. Question 2 - A secondary question relates to the interests of LLNL and SNL in the physics that HILL can address. This should be spelled out clearly. I would like to see the other labs be part of the discussion regarding how important this capability would be if built. Both sister Labs have a keen interest in the physics enabled by high-intensity, high-energy lasers, as evinced by the Z Petawatt and NIF ARC upgrades to their signature facilities. LANL scientists have teamed with scientists from both Laboratories in high-intensity laser 'first experiments' envisioned for HILL and we fully intend to continue these profitable discussions going forward. In the preparation of the HILL proposal, feedback was solicited from the broader HEDP and weapons science communities. The consensus view was that HILL filled a critical gap and that there was a need for a facility like HILL to address outstanding questions in weapons science. It was recognized that co-location of HILL with a facility such as MaRIE 1.0, Z, NIF, or

  20. Microbiological properties of poultry breast meat treated with high-intensity ultrasound.

    Science.gov (United States)

    Piñon, M I; Alarcon-Rojo, A D; Renteria, A L; Carrillo-Lopez, L M

    2018-01-03

    Lactic acid, psychrophilic, and mesophilic bacteria, Escherichia coli, Salmonella spp. and Staphylococcus aureus were enumerated on chicken breasts after treatment with different high intensity ultrasound (frequency 40 kHz, intensity 9.6 W/cm -2 ) application times (0, 30, and 50 min) and packaging atmospheres (aerobic and vacuum) after a 7-day storage. The experiment was performed in commercial 7-week-old chicken breasts. Counts were performed prior to and immediately after ultrasonication, and on the 7th day of chill-storage. After sonication and storage, mesophiles, psychrophiles, LAB and S. aureus increased statistically. Psychrophiles decreased significantly under anaerobic packaging. There were no differences among ultrasonication times in terms of mesophiles, psychrophiles, LAB, E. coli and Salmonella spp. S. aureus numbers had a significant reduction after 50 min sonication. Under these experimental conditions, high-intensity ultrasound for 50 min is a control method of S. aureus and the anaerobic packaging reduces numbers of psychrophiles in chicken breast. The effect of ultrasound is only significant after the storage time. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. Differential effect of metabolic alkalosis and hypoxia on high-intensity cycling performance.

    Science.gov (United States)

    Flinn, Samantha; Herbert, Kathryn; Graham, Kenneth; Siegler, Jason C

    2014-10-01

    The purpose of this study was to investigate the effects of sodium bicarbonate (NaHCO3) ingestion and acute hypoxic exposure on repeated bouts of high-intensity cycling to task failure. Twelve subjects completed 4 separate intermittent cycling bouts cycling bouts to task failure (120% peak power output for 30-second interspersed with 30-second active recovery) under the following conditions: normoxia (FIO2% at 20.93%) alkalosis (NA), normoxia placebo (NP), hypoxia (FIO2% at 14.7%) alkalosis (HA), and hypoxia placebo (HP). For the NA and HA trials, the buffer solution (0.3 g·kg of NaHCO3) was dispensed into gelatin capsules and consumed over 90 minutes with 1 L of water. Whole-blood acid-base findings demonstrated metabolic alkalosis in both NA and HA before exercise (HCO3: 32.8 ± 1.8 mmol·L). Time to task failure was significantly impaired in the hypoxic conditions (NA: 199.1 ± 62.3 seconds, NP: 183.8 ± 45.0 seconds, HA: 127.8 ± 27.9 seconds, HP: 133.3 ± 28.7 seconds; p metabolic acidosis during intermittent high-intensity cycling to task failure. In application, the use of hypoxia and NaHCO3 concurrently to improve performance under these conditions does not seem warranted.

  2. Development of the theragnostic optical system for a high-intensity laser therapy (HILT).

    Science.gov (United States)

    Lee, Sangkwan; Kim, Tae-Hoon; Youn, Jong-In

    2014-09-01

    Recently, high-intensity laser therapy (HILT) has been introduced for muscle disorders, but its efficacy has not been confirmed due to the absence of quantitative assessments and treatment feedback data in real-time. In this clinical study, a theragnostic optical system comprised of a high-intensity laser and a non-invasive optical monitoring system was developed to assess spasticity. To avoid interference between the two different light sources, the therapeutic wavelength for HILT was selected at 808 nm, one of the isosbestic points. The monitoring system based on a near-infrared spectroscopy (NIRS) was utilized for measuring hemoglobin concentrations according to a modified Beer-Lambert's law. The transitory HILT effect was evaluated from patients experiencing spasticity after stroke. Our results showed the proportionate relationship between manual muscle testing grades and the HILT effect on hemiplegic patients. The developed system proved to be useful for the simultaneous assessment and treatment of spasticity, and it holds promise for real-time monitoring of hemoglobin concentrations during laser therapy.

  3. REPORT OF THE SNOWMASS M6 WORKING GROUP ON HIGH INTENSITY PROTON SOURCES

    International Nuclear Information System (INIS)

    CHOU, W.; WEI, J.

    2001-01-01

    The M6 working group had more than 40 active participants (listed in Section 4). During the three weeks at Snowmass, there were about 50 presentations, covering a wide range of topics associated with high intensity proton sources. The talks are listed in Section 5. This group also had joint sessions with a number of other working groups, including E1 (Neutrino Factories and Muon Colliders), E5 (Fixed-Target Experiments), M1 (Muon Based Systems), T4 (Particle Sources), T5 (Beam dynamics), T7 (High Performance Computing) and T9 (Diagnostics). The M6 group performed a survey of the beam parameters of existing and proposed high intensity proton sources, in particular, of the proton drivers. The results are listed in Table 1. These parameters are compared with the requirements of high-energy physics users of secondary beams in Working Groups E1 and E5. According to the consensus reached in the E1 and E5 groups, the U.S. HEP program requires an intense proton source, a 1-4 MW Proton Driver, by the end of this decade

  4. Body armor, performance, and physiology during repeated high-intensity work tasks.

    Science.gov (United States)

    Larsen, Brianna; Netto, Kevin; Skovli, Daniel; Vincs, Kim; Vu, Sarah; Aisbett, Brad

    2012-11-01

    This study examined the effect of body armor during repeated, intermittent high-intensity simulated military work. Twelve males performed 11 repetitions of a military style circuit, wearing no armor on one occasion and full armor (approximately 17 kg) on another. Performance was measured by the time to complete individual work tasks plus overall circuit time to completion. Heart rate, intestinal temperature, and rating of perceived exertion were recorded after each circuit. Participants' circuit time to completion was 7.3 +/- 1.0 seconds slower (p armor. Shooting, vaulting, and crawling were also slower (0.8 +/- 0.2, 0.4 +/- 0.2, and 1.0 +/- 0.4 seconds, respectively; all p armor condition for circuit's 7 to 11 (p = 0.01-0.05). Rating of perceived exertion was higher (1 +/- 0; p = 0.03) when wearing armor. No differences were observed for heart rate. Wearing armor impairs repeated high-intensity military task performance. In the relatively short work time utilized, this decrement did not accrue over time. The impairment may, then, be related to the armor load, rather than accumulating fatigue.

  5. Cancer and Exercise: Warburg Hypothesis, Tumour Metabolism and High-Intensity Anaerobic Exercise

    Directory of Open Access Journals (Sweden)

    Peter Hofmann

    2018-01-01

    Full Text Available There is ample evidence that regular moderate to vigorous aerobic physical activity is related to a reduced risk for various forms of cancer to suggest a causal relationship. Exercise is associated with positive changes in fitness, body composition, and physical functioning as well as in patient-reported outcomes such as fatigue, sleep quality, or health-related quality of life. Emerging evidence indicates that exercise may also be directly linked to the control of tumour biology through direct effects on tumour-intrinsic factors. Beside a multitude of effects of exercise on the human body, one underscored effect of exercise training is to target the specific metabolism of tumour cells, namely the Warburg-type highly glycolytic metabolism. Tumour metabolism as well as the tumour–host interaction may be selectively influenced by single bouts as well as regularly applied exercise, dependent on exercise intensity, duration, frequency and mode. High-intensity anaerobic exercise was shown to inhibit glycolysis and some studies in animals showed that effects on tumour growth might be stronger compared with moderate-intensity aerobic exercise. High-intensity exercise was shown to be safe in patients; however, it has to be applied carefully with an individualized prescription of exercise.

  6. Effects of creatine supplementation on high-intensity intermittent exercise: discrepancies and methodological appraisals

    Directory of Open Access Journals (Sweden)

    Bruno Gualano

    2008-07-01

    Full Text Available http://dx.doi.org/10.5007/1980-0037.2008v10n2p189 After a brief review of the literature on the effects of creatine supplementation on high-intensity intermittent exercise performance, the main aim of this study was to discuss methodological differences between studies which could explain the discrepancies observed in the literature. The effects of creatine supplementation on high-intensity intermittent exercise performance have been investigated in depth. Although the results of much research demonstrates the effi cacy of this supplement, there is just as much evidence that does not support this ergogenic effect. The explanation for this divergence appears to be multifactorial, although it is always linked to methodological characteristics. Study design (crossover or parallel groups, individual variability of muscular creatine content, chronic high meat intake, sample size, exercise protocol characteristics (body weight dependence and time between series, and gender and age all differ between studies and are potentially the variables responsible, to differing extents, for the discrepancies observed in the literature. Studies involving young males, with parallel group design, adequate statistical power, control of the incorporation of creatine into muscles, food intake assessment and intermittent exercise protocols in which performance is independent of body weight and with rest-recovery intervals of 1 to 6 minutes, usually produce positive results. The many methodological factors which can contribute to divergence on the ergogenic effects of creatine should be considered in futures studies, as well as when prescribing creatine supplementation.

  7. Effectiveness of High Intensity Laser Therapy for Reduction of Pain in Knee Osteoarthritis

    Directory of Open Access Journals (Sweden)

    Anna Angelova

    2016-01-01

    Full Text Available Introduction. Osteoarthritis is the most common type of arthritis. It is the main cause of chronic musculoskeletal pain and disability among the elderly population. Aim. This is a pilot, randomized clinical study about the effect of high intensity laser therapy in patients with osteoarthritis of the knee (OA of the knee. Material and Method. 72 patients (aged between 39 and 83 years with (clinically and radiographically proved OA of the knee were included in the study. They were randomized in two groups: therapeutic (test one (n=37, 65,11 ± 1,40 (mean ± SD years old; patients were treated with HILT and control group (n=35, 64,71 ± 1,98; patients receive sham laser. Both groups had seven sessions of treatment. VAS and dolorimetry were used for assessment of pain before and after the therapy. Pedobarometric analysis (static and dynamic was used to assess comparatively the contact surface area and maximum pressure under the heel. Results. Pain levels measured by VAS and dolorimetry decreased significantly in the therapeutic group after seven days of treatment (p< 0,001. Conclusion. The results after seven days of treatment show more intensive and cumulative effect after the application of high intensity laser therapy in comparison to sham laser. This is the reason why HILT can be a method of choice in the treatment of gonarthrosis.

  8. Methodological Considerations When Quantifying High-Intensity Efforts in Team Sport Using Global Positioning System Technology.

    Science.gov (United States)

    Varley, Matthew C; Jaspers, Arne; Helsen, Werner F; Malone, James J

    2017-09-01

    Sprints and accelerations are popular performance indicators in applied sport. The methods used to define these efforts using athlete-tracking technology could affect the number of efforts reported. This study aimed to determine the influence of different techniques and settings for detecting high-intensity efforts using global positioning system (GPS) data. Velocity and acceleration data from a professional soccer match were recorded via 10-Hz GPS. Velocity data were filtered using either a median or an exponential filter. Acceleration data were derived from velocity data over a 0.2-s time interval (with and without an exponential filter applied) and a 0.3-second time interval. High-speed-running (≥4.17 m/s 2 ), sprint (≥7.00 m/s 2 ), and acceleration (≥2.78 m/s 2 ) efforts were then identified using minimum-effort durations (0.1-0.9 s) to assess differences in the total number of efforts reported. Different velocity-filtering methods resulted in small to moderate differences (effect size [ES] 0.28-1.09) in the number of high-speed-running and sprint efforts detected when minimum duration was GPS. Changes to how high-intensity efforts are defined affect reported data. Therefore, consistency in data processing is advised.

  9. Effects of Respiratory Muscle Warm-up on High-Intensity Exercise Performance

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    Taylor S. Thurston

    2015-11-01

    Full Text Available Exercise performance is partially limited by the functionality of the respiratory musculature. Training these muscles improves steady-state exercise performance. However, less is known about the efficacy of executing a respiratory muscle warm-up (RWU immediately prior to high-intensity exercise. Our study purpose was to use a practitioner-friendly airflow restriction device to investigate the effects of a high, medium, or low intensity RWU on short, high-intensity exercise and pulmonary, cardiovascular, and metabolic function. Eleven recreationally active, males (24.9 ± 4.2 y, 178.8 ± 9.0 cm, 78.5 ± 10.4 kg, 13.4% ± 4.2% body fat cycled at 85% peak power to exhaustion (TTE following four different RWU conditions (separate days, in random order: (1 high; (2 medium; (3 low airflow inspiration restriction, or no RWU. When analyzed as a group, TTE did not improve following any RWU (4.73 ± 0.33 min. However, 10 of the 11 participants improved ≥25 s in one of the three RWU conditions (average = 47.6 ± 13.2 s, which was significantly better than (p < 0.05 the control trial (CON. Neither blood lactate nor perceived difficulty was altered by condition. In general, respiratory exchange ratios were significantly lower during the early stages of TTE in all RWU conditions. Our findings suggest RWU efficacy is predicated on identifying optimal inspiration intensity, which clearly differs between individuals.

  10. The physiological stress response to high-intensity sprint exercise following the ingestion of sodium bicarbonate.

    Science.gov (United States)

    Peart, Daniel J; Kirk, Richard J; Hillman, Angela R; Madden, Leigh A; Siegler, Jason C; Vince, Rebecca V

    2013-01-01

    The purpose of this study was to investigate the effects of pre-exercise alkalosis on the physiological stress response to high-intensity exercise. Seven physically active males (age 22 ± 3 years, height 1.82 ± 0.06 m, mass 81.3 ± 8.4 kg and peak power output 300 ± 22 W) performed a repeated sprint cycle exercise following a dose of 0.3 g kg(-1) body mass of sodium bicarbonate (NaHCO(3)) (BICARB), or a placebo of 0.045 g kg(-1) body mass of sodium chloride (PLAC). Monocyte-expressed heat shock protein 72 (HSP72) and plasma thiobarbituric acid reactive substances (TBARS) were significantly attenuated in BICARB compared to PLAC (p = 0.04 and p = 0.039, respectively), however total anti-oxidant capacity, the ratio of oxidised to total glutathione, cortisol, interleukin 6 and interleukin 8 were not significantly induced by the exercise. In conclusion, monocyte-expressed HSP72 is significantly increased following high-intensity anaerobic exercise, and its attenuation following such exercise with the ingestion of NaHCO(3) is unlikely to be due to a decreased oxidative stress.

  11. The Utility of a High-intensity Exercise Protocol to Prospectively Assess ACL Injury Risk.

    Science.gov (United States)

    Bossuyt, F M; García-Pinillos, F; Raja Azidin, R M F; Vanrenterghem, J; Robinson, M A

    2016-02-01

    This study investigated the utility of a 5-min high-intensity exercise protocol (SAFT(5)) to include in prospective cohort studies investigating ACL injury risk. 15 active females were tested on 2 occasions during which their non-dominant leg was analysed before SAFT(5) (PRE), immediately after (POST0), 15 min after (POST15), and 30 min after (POST30). On the first occasion, testing included 5 maximum isokinetic contractions for eccentric and concentric hamstring and concentric quadriceps and on the second occasion, 3 trials of 2 landing tasks (i. e., single-leg hop and drop vertical jump) were conducted. Results showed a reduced eccentric hamstring peak torque at POST0, POST15 and POST30 (pACL injury risk and similar to observations from match simulations. Our findings therefore support the utility of a high-intensity exercise protocol such as SAFT(5) to strengthen injury screening tests and to include in prospective cohort studies where time constraints apply. © Georg Thieme Verlag KG Stuttgart · New York.

  12. The Effects of Electrostimulation and Core Exercises on Recovery After High-Intensity Exercise

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    Ahmet Mor

    2017-12-01

    Full Text Available Introduction and objectives: The purpose of this study was to determine the effects of electrostimulation and core exercises on recovery after high-intensity exercise. Methods: The participants of this study consists of 12 male bodybuilders who regularly train and between the ages 18-30. Tabata high intensity interval training (HIIT was applied with different recovery methods to the athletes on three different days and the recovery levels of athletes were analysed. Heart rate and blood lactate levels were measured at baseline (PRE at immediately after the HIIT (POST, at the 1 minutes after HIIT (1min, at the 5 minutes after HIIT (5min, and at the 10 minutes after HIIT (10min. On the rest days, serum lactate dehydrogenase (LDH and serum creatine kinase (CK  measurements were done to determine the muscle damage. Results: The in-group comparisons for lactate levels showed no significant difference (p>0,01. The level of lactate on the 10min was found to be significantly lower than the 5min in the core exercise group (p0,01. These results show that the lactate level reaches to the maximum level after HIIT, and the level of lactate decreases between the 5th and the 10th minutes. Discussion and conclusion: These indicate that the active recovery methods are more effective than the passive. It was found that the active recovery methods accelerate the lactate removal from the metabolism and provide effective recovery in short time during the recovery period after exercise.

  13. High-intensity exercise training for the prevention of type 2 diabetes mellitus.

    Science.gov (United States)

    Rynders, Corey A; Weltman, Arthur

    2014-02-01

    Aerobic exercise training and diet are recommended for the primary prevention of type 2 diabetes mellitus and cardiovascular disease. The American Diabetes Association (ADA) recommends that adults with prediabetes engage in ≥ 150 minutes per week of moderate activity and target a 7% weight loss. However, traditional moderate-intensity (MI) exercise training programs are often difficult to sustain for prediabetic adults; a commonly cited barrier to physical activity in this population is the "lack of time" to exercise. When matched for total energy expenditure, high-intensity (HI) exercise training has a lower overall time commitment compared with traditional low-intensity (LI) or MI exercise training. Several recent studies comparing HI exercise training with LI and MI exercise training reported that HI exercise training improves skeletal muscle metabolic control and cardiovascular function in a comparable and/or superior way relative to LI and MI exercise training. Although patients can accrue all exercise benefits by performing LI or MI activities such as walking, HI activities represent a time-efficient alternative to meeting physical activity guidelines. High-intensity exercise training is a potent tool for improving cardiometabolic risk for prediabetic patients with limited time and may be prescribed when appropriate.

  14. High Intensity Exercise: Can It Protect You from A Fast Food Diet?

    Science.gov (United States)

    Duval, Christian; Rouillier, Marc-Antoine; Rabasa-Lhoret, Rémi; Karelis, Antony D

    2017-08-26

    The purpose of this study was to assess the ability of high intensity exercise to counteract the deleterious effects of a fast food diet on the cardiometabolic profile of young healthy men. Fifteen men were subjected to an exclusive fast food diet from a popular fast food restaurant chain (three extra value meals/day + optional snack) for 14 consecutive days. Simultaneously, participants were asked to perform each day high intensity interval training (HIIT) (15 × 60 sec sprint intervals (~90% of maximal heart rate)) on a treadmill. Fast food diet and energy expenditure profiles of the participants during the intervention were assessed as well as body composition (DXA), cardiometabolic profile (lipid, hepatic enzymes, glycated hemoglobin, glucose, insulin, hsC-reactive protein (hsCRP) and blood pressure) and estimated maximal oxygen consumption (VO2 max) pre- and post-experiment. We found significant improvements for fat mass, lean body mass, estimated VO₂ max, fasting glucose, serum lipoprotein(a) and hsCRP after the intervention ( p fast food diet.

  15. Dose-Response of High-Intensity Training (HIT) on Atheroprotective miRNA-126 Levels

    Science.gov (United States)

    Schmitz, Boris; Schelleckes, Katrin; Nedele, Johanna; Thorwesten, Lothar; Klose, Andreas; Lenders, Malte; Krüger, Michael; Brand, Eva; Brand, Stefan-Martin

    2017-01-01

    Aim: MicroRNA-126 (miR-126) exerts beneficial effects on vascular integrity, angiogenesis, and atherosclerotic plaque stability. The purpose of this investigation was to analyze the dose-response relationship of high-intensity interval training (HIIT) on miR-126-3p and -5p levels. Methods: Sixty-one moderately trained individuals (females = 31 [50.8%]; 22.0 ± 1.84 years) were consecutively recruited and allocated into three matched groups using exercise capacity. During a 4-week intervention a HIIT group performed three exercise sessions/week of 4 × 30 s at maximum speed (all-out), a progressive HIIT (proHIIT) group performed three exercise sessions/week of 4 × 30 s at maximum speed (all-out) with one extra session every week (up to 7 × 30 s) and a low-intensity training (LIT) control group performed three exercise sessions/week for 25 min HIIT groups (after 4 min of high-intensity running). After the intervention, the LIT group presented an increase in miR-126-3p, while in the HIIT group, miR-126-3p levels were still reduced (all p HIIT (−1.05 ± 2.6 units). Conclusions: LIT and proHIIT may be performed to increase individual miR-126 levels. HIIT without progression was less effective in increasing miR-126. PMID:28611681

  16. A MOTIVATIONAL MUSIC AND VIDEO INTERVENTION IMPROVES HIGH-INTENSITY EXERCISE PERFORMANCE

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    Martin J. Barwood

    2009-09-01

    Full Text Available Music and video are utilised by recreational gym users to enhance their exercise experience. Music and video have not been investigated for their combined ergogenic effect during high intensity exercise. To induce fatigue, this study was performed in warm (~26°C, moist conditions (~50%RH. Six, non-acclimated, male participants took part in the study. Each participant completed three 30-minute exercise bouts on a motorised treadmill under three counterbalanced conditions on separate days: control (CON, motivational music plus video intervention (M, non-motivational intervention (NM. They completed a warm-up (5 km·h-1 [5 minutes], 9km·h-1 [10 minutes] followed by a maximal effort run (15 minutes. Participants did not receive any feedback of time elapsed, distance run or speed. Measures: Distance covered (metres, heart rate, blood lactate accumulation (Blac and ratings of perceived exertion (RPE. Participants in the M condition ran significantly further than in the NM (M: 3524 [388]metres; NM: 3110 [561]metres; CON: 3273 [458]metres and CON conditions, accumulated more Blac, but did not increase their peak RPE rating (p < 0.05. The M intervention improved tolerance of high intensity exercise in warm conditions. It was proposed that a change in attentional processing from internal (physical sensations to external perspective (music and video may have facilitated this improvement. These findings have strong implications for improving health, fitness and engagement in gym-based exercise programs

  17. Virtual coaching for the high-intensity training of a powerlifter following coronary artery bypass grafting.

    Science.gov (United States)

    Adams, Richard; Adams, Jenny; Qin, Huanying; Bilbrey, Tim; Schussler, Jeffrey M

    2015-01-01

    A 55-year-old powerlifter in Tennessee learned about the sport-specific, high-intensity cardiac rehabilitation training available in Dallas, Texas, and contacted the staff by phone. He was recovering from quadruple coronary artery bypass grafting (CABG) and had completed several weeks of traditional cardiac rehabilitation in his hometown, but the exercise program no longer met his needs. He wanted help in returning both to his normal training regimen and to powerlifting competition but was unable to attend the Dallas program in person. An exercise physiologist with the program devised a virtual coaching model in which the patient was sent a wrist blood pressure cuff for self-monitoring and was advised about exercises that would not harm his healing sternum, even as the weight loads were gradually increased. After 17 weeks of symptom-limited, high-intensity training that was complemented by phone and e-mail support, the patient was lifting heavier loads than he had before CABG. At a powerlifting competition 10 months after CABG, he placed first in his age group. This case report exemplifies the need for alternative approaches to the delivery of cardiac rehabilitation services.

  18. Comparison of high-intensity laser therapy and ultrasound treatment in the patients with lumbar discopathy.

    Science.gov (United States)

    Boyraz, Ismail; Yildiz, Ahmet; Koc, Bunyamin; Sarman, Hakan

    2015-01-01

    The aim of the present study was to evaluate the efficiency of high intensity laser and ultrasound therapy in patients who were diagnosed with lumbar disc herniation and who were capable of performing physical exercises. 65 patients diagnosed with lumbar disc were included in the study. The patients were randomly divided into three groups: Group 1 received 10 sessions of high intensity laser to the lumbar region, Group 2 received 10 sessions of ultrasound, and Group 3 received medical therapy for 10 days and isometric lumbar exercises. The efficacy of the treatment modalities was compared with the assessment of the patients before the therapy at the end of the therapy, and in third month after the therapy. Comparing the changes between groups, statically significant difference was observed in MH (mental health) parameter before treatment between Groups 1 and 2 and in MH parameter and VAS score in third month of the therapy between Groups 2 and 3. However, the evaluation of the patients after ten days of treatment did not show significant differences between the groups compared to baseline values. We found that HILT, ultrasound, and exercise were efficient therapies for lumbar discopathy but HILT and ultrasound had longer effect on some parameters.

  19. Comparison of High-Intensity Laser Therapy and Ultrasound Treatment in the Patients with Lumbar Discopathy

    Directory of Open Access Journals (Sweden)

    Ismail Boyraz

    2015-01-01

    Full Text Available The aim of the present study was to evaluate the efficiency of high intensity laser and ultrasound therapy in patients who were diagnosed with lumbar disc herniation and who were capable of performing physical exercises. 65 patients diagnosed with lumbar disc were included in the study. The patients were randomly divided into three groups: Group 1 received 10 sessions of high intensity laser to the lumbar region, Group 2 received 10 sessions of ultrasound, and Group 3 received medical therapy for 10 days and isometric lumbar exercises. The efficacy of the treatment modalities was compared with the assessment of the patients before the therapy at the end of the therapy, and in third month after the therapy. Comparing the changes between groups, statically significant difference was observed in MH (mental health parameter before treatment between Groups 1 and 2 and in MH parameter and VAS score in third month of the therapy between Groups 2 and 3. However, the evaluation of the patients after ten days of treatment did not show significant differences between the groups compared to baseline values. We found that HILT, ultrasound, and exercise were efficient therapies for lumbar discopathy but HILT and ultrasound had longer effect on some parameters.

  20. Accelerator technical design report for high-intensity proton accelerator facility project, J-PARC

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-03-01

    This report presents the detail of the technical design of the accelerators for the High-Intensity Proton Accelerator Facility Project, J-PARC. The accelerator complex comprises a 400-MeV room-temperature linac (600-MeV superconducting linac), 3-GeV rapid-cycling synchrotron (RCS), and a 50-GeV synchrotron (MR). The 400-MeV beam is injected to the RCS, being accelerated to 3 GEV. The 1-MW beam thus produced is guided to the Materials Life Science Experimental Facility, with both the pulsed spallation neutron source and muon source. A part of the beam is transported to the MR, which provides the 0.75-MW beam to either the Nuclear and Fundamental Particle Experimental Facility or the Neutrino Production Target. On the other hand, the beam accelerated to 600 MeV by the superconducting linac is used for the Nuclear Waster Transmutation Experiment. In this way, this facility is unique, being multipurpose one, including many new inventions and Research and Development Results. This report is based upon the accomplishments made by the Accelerator Group and others of the Project Team, which is organized on the basis of the Agreement between JAERI and KEK on the Construction and Research and Development of the High-Intensity Proton Accelerator Facility. (author)