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Sample records for cancer frequency intensity

  1. Efficacy of low-frequency low-intensity electrotherapy in the treatment of breast cancer-related lymphoedema: a cross-over randomized trial

    PubMed Central

    Tejero, Marta; Ferrer, Montse; Muniesa, Josep M; Duarte, Esther; Cunillera, Oriol; Escalada, Ferran

    2012-01-01

    Objective: To compare the efficacy of low-frequency low-intensity electrotherapy and manual lymphatic drainage in the treatment of chronic upper limb breast cancer-related lymphoedema. Design: Cross-over single-blind random clinical trial. Setting: Rehabilitation service. Participants: Thirty-six women with chronic upper limb breast cancer-related lymphoedema. Methods: Patients were randomized to undergo 10 sessions of manual lymphatic drainage followed by 10 sessions of low-frequency low-intensity electrotherapy or to undergo first low-frequency low-intensity electrotherapy followed by manual lymphatic drainage. There was a month of washout time between treatments. Each patient was examined just before and after each treatment. Researchers and outcome assessors were blinded for assigned treatment. Measures: Outcomes were lymphoedema volume, pain, heaviness and tightness, and health-related quality of life measured with the Functional Assessment of Cancer Therapy Questionnaire for Breast Cancer version 4 (FACT-B+4). Carry-over, period and treatment effects were analysed. Treatment effect was assessed using paired t-test. Results: Thirty patients finalized treatment. Comparing the changes in low-frequency low-intensity electrotherapy with manual lymphatic drainage changes, there were no significant differences. Low-frequency low-intensity electrotherapy did not reduce lymphoedema volume (mean of change = 19.77 mL, P = 0.36), but significant reductions were observed in pain, heaviness and tightness (mean of change = 13.1, 16.2 and 6.4 mm, respectively), and FACT-B+4 summaries improved significantly (Trial Outcome Index mean of change = 5.4, P = 0.015). Manual lymphatic drainage showed no significant changes in any of the outcomes Conclusion: Although there are no significant differences between treatment changes, the observed trend towards a better health-related quality of life is remarkable in low-frequency low-intensity electrotherapy. PMID:22172923

  2. Developing estimates of frequency and intensity of exposure to three types of metalworking fluids in a population-based case-control study of bladder cancer

    PubMed Central

    Friesen, Melissa C; Park, Dong-Uk; Colt, Joanne S; Baris, Dalsu; Schwenn, Molly; Karagas, Margaret R.; Armenti, Karla R.; Johnson, Alison; Silverman, Debra T; Stewart, Patricia A

    2014-01-01

    Background A systematic, transparent, and data-driven approach was developed to estimate frequency and intensity of exposure to straight, soluble, and synthetic/semi-synthetic metalworking fluids (MWFs) within a case-control study of bladder cancer in New England. Methods We assessed frequency using individual-level information from job-specific questionnaires wherever possible, then derived and applied job group-level patterns to likely exposed jobs with less information. Intensity estimates were calculated using a statistical model developed from measurements and determinants extracted from the published literature. Results For jobs with probabilities of exposure ≥0.5, median frequencies were 8 to 10 hours per week, depending on MWF type. Median intensities for these jobs were 2.5, 2.1, and 1.0 mg/m3 for soluble, straight, and synthetic/semi-synthetic MWFs, respectively. Conclusions Compared to case-by-case assessment, these data-driven decision rules are transparent and reproducible and may result in less biased estimates. These rules can also aid future exposure assessments of MWFs in population-based studies. PMID:25060071

  3. Optimization of low-frequency low-intensity ultrasound-mediated microvessel disruption on prostate cancer xenografts in nude mice using an orthogonal experimental design

    PubMed Central

    YANG, YU; BAI, WENKUN; CHEN, YINI; LIN, YANDUAN; HU, BING

    2015-01-01

    The present study aimed to provide a complete exploration of the effect of sound intensity, frequency, duty cycle, microbubble volume and irradiation time on low-frequency low-intensity ultrasound (US)-mediated microvessel disruption, and to identify an optimal combination of the five factors that maximize the blockage effect. An orthogonal experimental design approach was used. Enhanced US imaging and acoustic quantification were performed to assess tumor blood perfusion. In the confirmatory test, in addition to acoustic quantification, the specimens of the tumor were stained with hematoxylin and eosin and observed using light microscopy. The results revealed that sound intensity, frequency, duty cycle, microbubble volume and irradiation time had a significant effect on the average peak intensity (API). The extent of the impact of the variables on the API was in the following order: Sound intensity; frequency; duty cycle; microbubble volume; and irradiation time. The optimum conditions were found to be as follows: Sound intensity, 1.00 W/cm2; frequency, 20 Hz; duty cycle, 40%; microbubble volume, 0.20 ml; and irradiation time, 3 min. In the confirmatory test, the API was 19.97±2.66 immediately subsequent to treatment, and histological examination revealed signs of tumor blood vessel injury in the optimum parameter combination group. In conclusion, the Taguchi L18 (3)6 orthogonal array design was successfully applied for determining the optimal parameter combination of API following treatment. Under the optimum orthogonal design condition, a minimum API of 19.97±2.66 subsequent to low-frequency and low-intensity mediated blood perfusion blockage was obtained. PMID:26722279

  4. Rainfall intensity-duration-frequency formulas.

    USGS Publications Warehouse

    Chen, C.-L.

    1983-01-01

    A new general rainfall intensity-duration-frequency formula is presented, utilizing a method similar to, but more accurate than one previously developed. The previously developed formula was based on the average depth-duration ratio of about 40% and the mean depth-frequency ratio of 1.48. It is shown that this formula is only a particular form of the writer's more general formulation. -from Author

  5. Effect of Gaussian intensity profiles on difference-frequency generation

    NASA Astrophysics Data System (ADS)

    Rustagi, K. C.; Gupta, P. K.

    1980-04-01

    The effect of a Gaussian intensity profile on the efficiency of difference-frequency generation in the near-field limit is evaluated. The effect of a nonuniform intensity profile in the incident beams are significant qualitatively as well as quantitatively. These effects become more important when the incident pump intensity is much larger than the incident idler intensity.

  6. [Frequency of cancer at older ages].

    PubMed

    Hill, Catherine; Doyon, Françoise

    2008-05-28

    The dependency between the risk of death and age is analysed, and the contribution of cancer to the overall risk of death is evaluated as a function of age. The frequency of the different cancer sites is described in different age groups. Lastly cancer mortality trends are presented by age. The risk of death from cancer increases markedly with age, but the risk of a death from a cardiovascular disease increases even more rapidly, consequently the importance of cancer as a cause of death decreases with age. In the male population, lung and head and neck cancers are the most frequent cancers before age 65, whereas prostate and colorectal cancers are more frequent at older ages. In the female population, breast and colorectal cancers are the most frequent cancers except for mortality before age 65 where lung cancer is the second killer after breast cancer. The risk of cancer death decreases in recent years for all age groups.

  7. Problems of intensive therapy in childhood cancer

    SciTech Connect

    Skelton, J.; Pizzo, P.A.

    1986-07-15

    Tremendous progress has been made in the treatment of childhood cancers. Certain hematologic malignancies have an impressive cure rate with the current intensive antineoplastic treatment regimens. There is optimism that the treatment of children who have advanced stage solid tumors with intensive, multimodality therapy may improve their chances for long-term survival. These treatment programs, though potentially curative, are highly toxic, with severe myelosuppression and damage to other organ systems. An awareness of these potential toxicities, an understanding of how to prevent or minimize certain problems, and the ability to treat those complications which do arise are all essential to the successful management of childhood cancer. 206 references.

  8. Trends in Northern Hemisphere surface cyclone frequency and intensity

    USGS Publications Warehouse

    McCabe, G.J.; Clark, M.P.; Serreze, M.C.

    2001-01-01

    One of the hypothesized effects of global warming from increasing concentrations of greenhouse gases is a change in the frequency and/or intensity of extratropical cyclones. In this study, winter frequencies and intensities of extratropical cyclones in the Northern Hemisphere for the period 1959-97 are examined to determine if identifiable trends are occurring. Results indicate a statistically significant decrease in midlatitude cyclone frequency and a significant increase in high-latitude cyclone frequency. In addition, storm intensity has increased in both the high and midlatitudes. The changes in storm frequency correlate with changes in winter Northern Hemisphere temperature and support hypotheses that global warming may result in a northward shift of storm tracks in the Northern Hemisphere.

  9. Observed emotion frequency versus intensity as predictors of socioemotional maladjustment.

    PubMed

    Hernández, Maciel M; Eisenberg, Nancy; Valiente, Carlos; Spinrad, Tracy L; VanSchyndel, Sarah K; Diaz, Anjolii; Berger, Rebecca H; Silva, Kassondra M; Southworth, Jody; Piña, Armando A

    2015-12-01

    The purpose of this study was to assess whether observed emotional frequency (the proportion of instances an emotion was observed) and intensity (the strength of an emotion when it was observed) uniquely predicted kindergartners' (N = 301) internalizing and externalizing problems. Analyses were tested in a structural equation modeling (SEM) framework with data from multireporters (reports of problem behaviors from teachers and parents) and naturalistic observations of emotion in the fall semester. For observed positive emotion, both frequency and intensity negatively predicted parent- or teacher-reported internalizing symptoms. Anger frequency positively predicted parent- and teacher-reported externalizing symptoms, whereas anger intensity positively predicted parent- and teacher-reported externalizing and parent-reported internalizing symptoms. The findings support the importance of examining both aspects of emotion when predicting maladjustment.

  10. All-optical frequency and intensity noise suppression of single-frequency fiber laser.

    PubMed

    Li, Can; Xu, Shanhui; Huang, Xiang; Xiao, Yu; Feng, Zhouming; Yang, Changsheng; Zhou, Kaijun; Lin, Wei; Gan, Jiulin; Yang, Zhongmin

    2015-05-01

    An all-optical frequency and intensity noise suppression technique of a single-frequency fiber laser is demonstrated. By exploiting the recursive noise reduction effect of a semiconductor optical amplifier (SOA) in a self-injection locked fiber laser, the frequency and intensity noise of the laser are remarkably suppressed in a significantly wide frequency range. In addition to the linewidth suppression from 3.5 kHz to 700 Hz, the frequency noise has been reduced by ∼25  dB. After suppression, the relative intensity noise (RIN) is within 5 dB of the shot noise limit at frequencies from 1.5 to 3 MHz, and the frequency range of the suppression reaches about 30 MHz. The relaxation oscillation peak is observed to shift to lower frequencies and is reduced by about 35 dB from -90  dB/Hz to -125  dB/Hz. It is believed that the achieved low noise makes the fiber laser a promising candidate in applications such as ultra-long haul coherent optical communication and LIDAR.

  11. Intense harmonics generation with customized photon frequency and optical vortex

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaomei; Shen, Baifei; Shi, Yin; Zhang, Lingang; Ji, Liangliang; Wang, Xiaofeng; Xu, Zhizhan; Tajima, Toshiki

    2016-08-01

    An optical vortex with orbital angular momentum (OAM) enriches the light and matter interaction process, and helps reveal unexpected information in relativistic nonlinear optics. A scheme is proposed for the first time to explore the origin of photons in the generated harmonics, and produce relativistic intense harmonics with expected frequency and an optical vortex. When two counter-propagating Laguerre-Gaussian laser pulses impinge on a solid thin foil and interact with each other, the contribution of each input pulse in producing harmonics can be distinguished with the help of angular momentum conservation of photons, which is almost impossible for harmonic generation without an optical vortex. The generation of tunable, intense vortex harmonics with different photon topological charge is predicted based on the theoretical analysis and three-dimensional particle-in-cell simulations. Inheriting the properties of OAM and harmonics, the obtained intense vortex beam can be applied in a wide range of fields, including atom or molecule control and manipulation.

  12. Intense harmonics generation with customized photon frequency and optical vortex

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaomei; Shen, Baifei; Shi, Yin; Zhang, Lingang; Ji, Liangliang; Wang, Xiaofeng; Xu, Zhizhan; Tajima, Toshiki

    2016-08-01

    An optical vortex with orbital angular momentum (OAM) enriches the light and matter interaction process, and helps reveal unexpected information in relativistic nonlinear optics. A scheme is proposed for the first time to explore the origin of photons in the generated harmonics, and produce relativistic intense harmonics with expected frequency and an optical vortex. When two counter-propagating Laguerre–Gaussian laser pulses impinge on a solid thin foil and interact with each other, the contribution of each input pulse in producing harmonics can be distinguished with the help of angular momentum conservation of photons, which is almost impossible for harmonic generation without an optical vortex. The generation of tunable, intense vortex harmonics with different photon topological charge is predicted based on the theoretical analysis and three-dimensional particle-in-cell simulations. Inheriting the properties of OAM and harmonics, the obtained intense vortex beam can be applied in a wide range of fields, including atom or molecule control and manipulation.

  13. Frequency domain stress intensity calibration of damped cracked panels

    NASA Technical Reports Server (NTRS)

    Doyle, James F.; Rizzi, Stephen A.

    1993-01-01

    This paper discusses two schemes for doing finite element K calibration in the frequency domain. The baseline scheme uses the definition of K as a limit toward the crack tip. The limiting process requires using a very fine mesh around the crack tip making the scheme computationally very expensive. It is shown that the behavior of K as a function of frequency is very similar to a modal response. Taking advantage of this, a more efficient scheme involves a modal analysis of the cracked sheet and scaling the response to that of the static stress intensity. In this way, only a static K calibration need be performed. All the examples shown are for a frequency range spanning multiple resonances and with two levels of damping.

  14. Frequency and Intensity of drought events over Ebro River basin

    NASA Astrophysics Data System (ADS)

    Valencia, J. L.; Saa-Requejo, A.; Gascó, J. M.; Tarquis, A. M.

    2012-04-01

    Lately, several researchers have pointed out that climate change is expected to increase temperatures and lower rainfall in Mediterranean regions, simultaneously increasing the intensity of extreme rainfall events. These changes could have consequences regarding rainfall regime, erosion, sediment transport and water quality, soil management, and new designs in diversion ditches. Climate change is expected to result in increasingly unpredictable and variable rainfall, in amount and timing, changing seasonal patterns and increasing the frequency of extreme weather events. Consequently, the evolution of frequency and intensity of drought periods is of most important as in agro-ecosystems many processes will be affected by them. Realising the complex and important consequences of an increasing frequency of extreme droughts at the Ebro River basin, our aim is to study the evolution of drought events at this site statistically, with emphasis on the occurrence and intensity of them. For this purpose, fourteen meteorological stations were selected based on the length of the rainfall series and the climatic classification to obtain a representative untreated dataset from the river basin. Daily rainfall series from 1957 to 2002 were obtained from each meteorological station and no-rain period frequency as the consecutive numbers of days were extracted. Based on this data, we study changes in the probability distribution in several sub-periods. Moreover we used the Standardized Precipitation Index (SPI) for identification of drought events in a year scale and then we use this index to fit log-linear models to the contingency tables between the SPI index and the sub-periods, this adjusted is carried out with the help of ANOVA inference. Funding provided by ENESA, under projects P030225764 and P070225564, and by Spanish Ministerio de Ciencia e Innovación (MICINN) through project no. AGL2010-21501/AGR is greatly appreciated.

  15. Diversity-disturbance relationships: frequency and intensity interact.

    PubMed

    Hall, Alex R; Miller, Adam D; Leggett, Helen C; Roxburgh, Stephen H; Buckling, Angus; Shea, Katriona

    2012-10-23

    An influential ecological theory, the intermediate disturbance hypothesis (IDH), predicts that intermediate levels of disturbance will maximize species diversity. Empirical studies, however, have described a wide variety of diversity-disturbance relationships (DDRs). Using experimental populations of microbes, we show that the form of the DDR depends on an interaction between disturbance frequency and intensity. We find that diversity shows a monotonically increasing, unimodal or flat relationship with disturbance, depending on the values of the disturbance aspects considered. These results confirm recent theoretical predictions, and potentially reconcile the conflicting body of empirical evidence on DDRs.

  16. Frequency and duration of handwashing in an intensive care unit.

    PubMed

    Graham, M

    1990-04-01

    The effects on hand decontamination of the introduction of an antiseptic handrub lotion in an intensive care unit was studied. To obtain baseline data, nursing, medical, physiotherapy, radiology, and orderly staff members were observed. Further observations were carried out after the introduction of the handrub lotion. Patient care activities were classified as high or low, according to the degree of contact with the patients or their equipment. A total of 884 patient contacts and 341 hand decontamination episodes was observed: 440 contacts and 140 handwashes in stage one (32%) and 444 contacts and 201 handwashes in stage two (45%). There was an increase of 13% in hand decontamination frequency after the introduction of the handrub lotion. The data indicate that the frequency of hand decontamination is below levels recommended by infection control authorities. Increasing the accessibility of hand decontamination facilities did result in a slight increase in handwashing compliance.

  17. Convective Cloud Towers and Precipitation Initiation, Frequency and Intensity

    NASA Astrophysics Data System (ADS)

    Vant-hull, B.; Mahani, S. E.; Autones, F.; Rabin, R.; Mecikalski, J. R.; Khanbilvardi, R.

    2012-12-01

    : Geosynchronous satellite retrieval of precipitation is desirable because it would provide continuous observation throughout most of the globe in regions where radar data is not available. In the current work the distribution of precipitation rates is examined as a function of cloud tower area and cloud top temperature. A thunderstorm tracking algorithm developed at Meteo-France is used to track cumulus towers that are matched up with radar data at 5 minute 1 km resolution. It is found that roughly half of the precipitation occurs in the cloud mass that surrounds the towers, and when a tower is first detected the precipitation is already in progress 50% of the time. The average density of precipitation per area is greater as the towers become smaller and colder, yet the averaged shape of the precipitation intensity distribution is remarkably constant in all convective situations with cloud tops warmer than 220 K. This suggests that on average all convective precipitation events look the same, unaffected by the higher frequency of occurrence per area inside the convective towers. Only once the cloud tops are colder than 220 K does the precipitation intensity distribution become weighted towards higher instantaneous intensities. Radar precipitation shown in shades of green to blue, lightning in orange; black diamonds are coldest points in each tower. Ratio of number of pixels of given precipitation inside versus outside the convective towers, for various average cloud top temperatures. A flat plot indicates the distribution of rainfall inside and outside the towers has the same shape.

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

    SciTech Connect

    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

  19. Frequency and intensity of comet showers from the Oort cloud

    SciTech Connect

    Heisler, J.; Alcock, C.; Tremaine, S.

    1987-05-01

    The nature of new comets and the frequency and intensity of comet showers are presently studied by means of a simulation in which an ensemble of one million comets is perturbed at random times by the Bahcall-Soneira (1980) Galaxy model's population of main sequence stars and white dwarfs. The time-integrated flux is dominated by the showers for comets whose semimajor axes are less than about 30,000 AU. The inclusion of tidal effects increases the loss rate of comets with semimajor axes between 10,000 and 20,000 AU by a factor of about 4, so that the Galactic tide, rather than individual stellar perturbations, is the dominant Oort cloud evolution-driving mechanism. 44 references.

  20. Photodetachment of H- from intense, short, high-frequency pulses

    NASA Astrophysics Data System (ADS)

    Shao, Hua-Chieh; Robicheaux, F.

    2016-05-01

    We study the photodetachment of an electron from the hydrogen anion due to short, high-frequency laser pulses by numerically solving the time-dependent Schrödinger equation. Simulations are performed to investigate the dependence of the photoelectron spectra on the duration, chirp, and intensity of the pulses. Specifically, we concentrate on the low-energy distributions in the spectra that result from the Raman transitions of the broadband pulses. Contrary to the one-photon ionization, the low-energy distribution maintains a similar width as the laser bandwidth is expanded by chirping the pulses. In addition, we study the transitions of the ionization dynamics from the perturbative to strong-field regime. At high intensities, the positions of the net one- and two-photon absorption peaks in the spectrum shifts and the peaks split to multiple subpeaks because of the multiphoton effects. Moreover, although the one- and two-photon peaks and low-energy distribution exhibit saturation of the ionization yields, the latter shows relatively mild saturation. This work has been supported by DOE under Award No. DE-SC0012193.

  1. Low intensity ultrasound stimulates osteoblast migration at different frequencies.

    PubMed

    Man, Jennifer; Shelton, Richard M; Cooper, Paul R; Landini, Gabriel; Scheven, Ben A

    2012-09-01

    This study investigated the effects of different frequencies of low intensity ultrasound on osteoblast migration using an in vitro scratch-wound healing assay. Mouse calvarial-derived MC3T3-E1 osteoblasts in culture were exposed to continuous 45 kHz ultrasound (25 mW/cm(2)) or pulsed 1 MHz ultrasound (250 mW/cm(2)) for 30 min followed by 2 days' culture. Ultrasound treatment with either kHz or MHz output similarly and significantly increased cell numbers after 2 days in culture compared with untreated control cultures. In the scratch-wound healing assay the presence of the cell proliferation inhibitor mitomycin C (MMC) did not influence scratch-wound closure in control cultures indicating that cell migration was responsible for the in vitro wound healing. Application of ultrasound significantly stimulated wound closure. MMC did not affect kHz-stimulated in vitro wound healing; however, MMC reduced in part the scratch-wound closure rate in MHz-treated cultures suggesting that enhanced cell proliferation as well as migration was involved in the healing promoted by MHz ultrasound. In conclusion, both continuous kHz and pulsed MHz ultrasound promoted osteoblastic migration; however, subtle differences were apparent in the manner the different ultrasound regimens enhanced in vitro scratch-wound healing.

  2. Radar QPE for hydrological design: Intensity-Duration-Frequency curves

    NASA Astrophysics Data System (ADS)

    Marra, Francesco; Morin, Efrat

    2015-04-01

    Intensity-duration-frequency (IDF) curves are widely used in flood risk management since they provide an easy link between the characteristics of a rainfall event and the probability of its occurrence. They are estimated analyzing the extreme values of rainfall records, usually basing on raingauge data. This point-based approach raises two issues: first, hydrological design applications generally need IDF information for the entire catchment rather than a point, second, the representativeness of point measurements decreases with the distance from measure location, especially in regions characterized by steep climatological gradients. Weather radar, providing high resolution distributed rainfall estimates over wide areas, has the potential to overcome these issues. Two objections usually restrain this approach: (i) the short length of data records and (ii) the reliability of quantitative precipitation estimation (QPE) of the extremes. This work explores the potential use of weather radar estimates for the identification of IDF curves by means of a long length radar archive and a combined physical- and quantitative- adjustment of radar estimates. Shacham weather radar, located in the eastern Mediterranean area (Tel Aviv, Israel), archives data since 1990 providing rainfall estimates for 23 years over a region characterized by strong climatological gradients. Radar QPE is obtained correcting the effects of pointing errors, ground echoes, beam blockage, attenuation and vertical variations of reflectivity. Quantitative accuracy is then ensured with a range-dependent bias adjustment technique and reliability of radar QPE is assessed by comparison with gauge measurements. IDF curves are derived from the radar data using the annual extremes method and compared with gauge-based curves. Results from 14 study cases will be presented focusing on the effects of record length and QPE accuracy, exploring the potential application of radar IDF curves for ungauged locations and

  3. Projection of future changes in the frequency of intense tropical cyclones

    NASA Astrophysics Data System (ADS)

    Sugi, Masato; Murakami, Hiroyuki; Yoshida, Kohei

    2016-09-01

    Recent modeling studies have consistently shown that the global frequency of tropical cyclones will decrease but that of very intense tropical cyclones may increase in the future warmer climate. It has been noted, however, that the uncertainty in the projected changes in the frequency of very intense tropical cyclones, particularly the changes in the regional frequency, is very large. Here we present a projection of the changes in the frequency of intense tropical cyclones estimated by a statistical downscaling of ensemble of many high-resolution global model experiments. The results indicate that the changes in the frequency of very intense (category 4 and 5) tropical cyclones are not uniform on the globe. The frequency will increase in most regions but decrease in the south western part of Northwest Pacific, the South Pacific, and eastern part of the South Indian Ocean.

  4. A REVIEW OF LOW-INTENSITY ULTRASOUND FOR CANCER THERAPY

    PubMed Central

    WOOD, ANDREW K. W.; SEHGAL, CHANDRA M.

    2015-01-01

    The literature describing the use of low-intensity ultrasound in four major areas of cancer therapy was reviewed - sonodynamic therapy, ultrasound mediated chemotherapy, ultrasound mediated gene delivery and antivascular ultrasound therapy. Each technique consistently resulted in the death of cancer cells and the bioeffects of ultrasound were primarily attributed to thermal actions and inertial cavitation. In each therapeutic modality, theranostic contrast agents composed of microbubbles played a role in both therapy and vascular imaging. The development of these agents is important as it establishes a therapeutic-diagnostic platform which can monitor the success of anti-cancer therapy. Little attention, however, has been given to either the direct assessment of the underlying mechanisms of the observed bioeffects or to the viability of these therapies in naturally occurring cancers in larger mammals; if such investigations provided encouraging data there could be a prompt application of a therapy technique in treating cancer patients. PMID:25728459

  5. Leg stiffness adjustment during hopping at different intensities and frequencies.

    PubMed

    Mrdakovic, Vladimir; Ilic, Dusko; Vulovic, Radun; Matic, Milan; Jankovic, Nenad; Filipovic, Nenad

    2014-01-01

    Understanding leg and joint stiffness adjustment during maximum hopping may provide important information for developing more effective training methods. It has been reported that ankle stiffness has major influence on stable spring-mass dynamics during submaximal hopping, and that knee stiffness is a major determinant for hopping performance during maximal hopping task. Furthermore, there are no reports on how the height of the previous hop could affect overall stiffness modulation of the subsequent maximum one. The purpose of the present study was to determine whether and how the jump height of the previous hop affects leg and joint stiffness for subsequent maximum hop. Ten participants completed trials in which they repeatedly hopped as high as possible (MX task) and trials in which they were instructed to perform several maximum hops with 3 preferred (optimal) height hops between each of them (P3MX task). Both hopping tasks were performed at 2.2 Hz hopping frequency and at the participant's preferred (freely chosen) frequency as well. By comparing results of those hopping tasks, we found that ankle stiffness at 2.2 Hz ( p = 0.041) and knee stiffness at preferred frequency ( p = 0.045) was significantly greater for MX versus P3MX tasks. Leg stiffness for 2.2 Hz hopping is greater than for the preferred frequency. Ankle stiffness is greater for 2.2 Hz than for preferred frequencies; opposite stands for knee stiffness. The results of this study suggest that preparatory hop height can be considered as an important factor for modulation of maximum hop. PMID:25308379

  6. Structure, Anharmonic Vibrational Frequencies, and Intensities of NNHNN(+).

    PubMed

    Yu, Qi; Bowman, Joel M; Fortenberry, Ryan C; Mancini, John S; Lee, Timothy J; Crawford, T Daniel; Klemperer, William; Francisco, Joseph S

    2015-11-25

    A semiglobal potential energy surface (PES) and quartic force field (QFF) based on fitting high-level electronic structure energies are presented to describe the structures and spectroscopic properties of NNHNN(+). The equilibrium structure of NNHNN(+) is linear with the proton equidistant between the two nitrogen groups and thus of D(∞h) symmetry. Vibrational second-order perturbation theory (VPT2) calculations based on the QFF fails to describe the proton "rattle" motion, i.e., the antisymmetric proton stretch, due to the very flat nature of PES around the global minimum but performs properly for other modes with sharper potential wells. Vibrational self-consistent field/virtual state configuration interaction (VSCF/VCI) calculations using a version of MULTIMODE without angular momentum terms successfully describe this motion and predict the fundamental to be at 759 cm(-1). This is in good agreement with the value of 746 cm(-1) from a fixed-node diffusion Monte Carlo calculation and the experimental Ar-tagged result of 743 cm(-1). Other VSCF/VCI energies are in good agreement with other experimentally reported ones. Both double-harmonic intensity and rigorous MULTIMODE intensity calculations show the proton-transfer fundamental has strong intensity. PMID:26529262

  7. High-intensity focused ultrasound therapy for prostate cancer.

    PubMed

    Uchida, Toyoaki; Nakano, Mayura; Hongo, Satoko; Shoji, Sunao; Nagata, Yohishiro; Satoh, Takefumi; Baba, Shiro; Usui, Yukio; Terachi, Toshiro

    2012-03-01

    Recent advances in high-intensity focused ultrasound, which was developed in the 1940s as a viable thermal tissue ablation approach, have increased its popularity. High-intensity focused ultrasound is currently utilized the most in Europe and Japan, but has not yet been approved by the Food and Drug Administration, USA, for this indication. The purpose of the present report is to review the scientific foundation of high-intensity focused ultrasound technology and the clinical outcomes achieved with commercially available devices. Recently published articles were reviewed to evaluate the current status of high-intensity focused ultrasound as a primary or salvage treatment option for localized prostate cancer. Improvements in the clinical outcome as a result of technical, imaging and technological advancements are described herein. A wide range of treatment options for organ-confined prostate cancer is available. However, high-intensity focused ultrasound is an attractive choice for men willing to choose less invasive options, although establishing the efficacy of high-intensity focused ultrasound requires longer follow-up periods. Technological advances, together with cultural and economic factors, have caused a dramatic shift from traditional open, radical prostatectomy to minimally invasive techniques. High-intensity focused ultrasound is likely to play a significant role in the future of oncology practice. PMID:22188161

  8. Patients with cancer in the intensive monitoring unit. New perspectives.

    PubMed

    Prieto Del Portillo, I; Polo Zarzuela, M; Pujol Varela, I

    2014-10-01

    In recent years, there has been a significant improvement in the survival of patients with cancer in intensive care units (ICUs). Advances in medical and surgical treatments and better selection of patients has helped improve the life expectancy of this type of patient. An appropriate and early resuscitation in the ICU, without initial limitations on the life support techniques, has been shown to also decrease the mortality of patients with cancer. At present, we should not deny admission to the ICU based only on the underlying neoplastic disease. However, the mortality rate for patients with cancer in the ICU, especially those with hematologic disease, remains high. In some cases, an ICU admission test (ICU test) is required for at least 3 days to identify patients who can benefit from intensive treatment. We would like to propose a decision algorithm for ICU admission that will help in making decisions in an often complex situation.

  9. Patients with cancer in the intensive monitoring unit. New perspectives.

    PubMed

    Prieto Del Portillo, I; Polo Zarzuela, M; Pujol Varela, I

    2014-10-01

    In recent years, there has been a significant improvement in the survival of patients with cancer in intensive care units (ICUs). Advances in medical and surgical treatments and better selection of patients has helped improve the life expectancy of this type of patient. An appropriate and early resuscitation in the ICU, without initial limitations on the life support techniques, has been shown to also decrease the mortality of patients with cancer. At present, we should not deny admission to the ICU based only on the underlying neoplastic disease. However, the mortality rate for patients with cancer in the ICU, especially those with hematologic disease, remains high. In some cases, an ICU admission test (ICU test) is required for at least 3 days to identify patients who can benefit from intensive treatment. We would like to propose a decision algorithm for ICU admission that will help in making decisions in an often complex situation. PMID:24776089

  10. Spike-frequency adaptation generates intensity invariance in a primary auditory interneuron.

    PubMed

    Benda, Jan; Hennig, R Matthias

    2008-04-01

    Adaptation of the spike-frequency response to constant stimulation, as observed on various timescales in many neurons, reflects high-pass filter properties of a neuron's transfer function. Adaptation in general, however, is not sufficient to make a neuron's response independent of the mean intensity of a sensory stimulus, since low frequency components of the stimulus are still transmitted, although with reduced gain. We here show, based on an analytically tractable model, that the response of a neuron is intensity invariant, if the fully adapted steady-state spike-frequency response to constant stimuli is independent of stimulus intensity. Electrophysiological recordings from the AN1, a primary auditory interneuron of crickets, show that for intensities above 60 dB SPL (sound pressure level) the AN1 adapted with a time-constant of approximately 40 ms to a steady-state firing rate of approximately 100 Hz. Using identical random amplitude-modulation stimuli we verified that the AN1's spike-frequency response is indeed invariant to the stimulus' mean intensity above 60 dB SPL. The transfer function of the AN1 is a band pass, resulting from a high-pass filter (cutoff frequency at 4 Hz) due to adaptation and a low-pass filter (100 Hz) determined by the steady-state spike frequency. Thus, fast spike-frequency adaptation can generate intensity invariance already at the first level of neural processing.

  11. Intense electrostatic waves near the upper hybrid resonance frequency. [beyond plasmapause

    NASA Technical Reports Server (NTRS)

    Kurth, W. S.; Craven, J. D.; Frank, L. A.; Gurnett, D. A.

    1979-01-01

    Plasma wave measurements using instruments on the Imp 6 and Hawkeye satellites are utilized in a study of very intense electrostatic waves near the upper hybrid resonance frequency in the region just outside the plasmapause. Studies of these electrostatic disturbances show that the events occur at local times and at magnetic latitudes varying from the equator to 50 deg, and the polarization of these waves is such that the wave electric field vector is oriented perpendicular to the geomagnetic field. In most cases the center frequency of the intense waves corresponds to an (n + 1/2) fg(-) harmonic near the upper hybrid resonance frequency. The hot distribution on function is described for a few events showing temperature anisotropy and a loss cone distribution. A possible mechanism for producing intense waves near the upper hybrid resonance frequency is suggested, and evidence which indicates that the intense electrostatic waves may be a source of nonthermal continuum radiation is given.

  12. Features of electromagnetic radiation time-and-frequency fluctuation intensity distributions from human brain structures.

    PubMed

    Kublanov, V S; Gasilov, V L; Kazakov, Y E

    2000-01-01

    Time-and-frequency fluctuation intensity distributions' analysis is made of the electromagnetic radiation obtained from deep human brain structures. The role of monitoring the distribution changes due to various cerebral circulation disorders is explained.

  13. Cancer Knowledge and Examination Frequency in College Students.

    ERIC Educational Resources Information Center

    Craun, Ann M.; Deffenbacher, Jerry L.

    1981-01-01

    A study investigated whether the personality construct of repression-sensitization could identify which college students would or would not practice regular examinations for breast, cervical, or testicular cancer. Although knowledge of cancer increased after the lecture, no change was found in the frequency of breast self-examination while…

  14. Computed tomography in evolution of testicular cancer during intensive chemotherapy.

    PubMed

    Javadpour, N; Anderson, T; Doppman, J L

    1979-10-01

    The evolution of malignant testicular tumor to mature teratoma has been studied in 4 patients. Computed tomography has been helpful in early diagnosis of this biologic phenomenon in these patients receiving intensive chemotherapy for disseminated non-seminomatous testicular cancer. Although the potential significance of this conversion in terms of survival is not known its early recognition by computed tomography has been useful in selecting and monitoring the therapy of these patients.

  15. High-Intensity Focused Ultrasound Treatment for Advanced Pancreatic Cancer

    PubMed Central

    Zhou, Yufeng

    2014-01-01

    Pancreatic cancer is under high mortality but has few effective treatment modalities. High-intensity focused ultrasound (HIFU) is becoming an emerging approach of noninvasively ablating solid tumor in clinics. A variety of solid tumors have been tried on thousands of patients in the last fifteen years with great success. The principle, mechanism, and clinical outcome of HIFU were introduced first. All 3022 clinical cases of HIFU treatment for the advanced pancreatic cancer alone or in combination with chemotherapy or radiotherapy in 241 published papers were reviewed and summarized for its efficacy, pain relief, clinical benefit rate, survival, Karnofsky performance scale (KPS) score, changes in tumor size, occurrence of echogenicity, serum level, diagnostic assessment of outcome, and associated complications. Immune response induced by HIFU ablation may become an effective way of cancer treatment. Comments for a better outcome and current challenges of HIFU technology are also covered. PMID:25053938

  16. Frequency dependence and intensity fluctuations due to shallow water internal waves.

    PubMed

    Badiey, Mohsen; Katsnelson, Boris G; Lynch, James F; Pereselkov, Serguey

    2007-08-01

    A theory and experimental results for sound propagation through an anisotropic shallow water environment are presented to examine the frequency dependence of the scintillation index in the presence of internal waves. The theory of horizontal rays and vertical modes is used to establish the azimutal and frequency behavior of the sound intensity fluctuations, specifically for shallow water broadband acoustic signals propagating through internal waves. This theory is then used to examine the frequency dependent, anisotropic acoustic field measured during the SWARM'95 experiment. The frequency dependent modal scintillation index is described for the frequency range of 30-200 Hz on the New Jersey continental shelf.

  17. Intensity-modulated radiotherapy in the treatment of prostate cancer.

    PubMed

    Bauman, G; Rumble, R B; Chen, J; Loblaw, A; Warde, P

    2012-09-01

    Three-dimensional conformal radiotherapy (3DCRT) as the primary treatment for prostate cancer has improved outcomes compared with conventional radiotherapy, but with an associated increase in toxicity due to radiation effects on the bladder and rectum. Intensity-modulated radiotherapy (IMRT) is a newer method of radiotherapy that uses intensity-modulated beams that can provide multiple intensity levels for any single beam direction and any single source position allowing concave dose distributions and dose gradients with narrower margins than those possible using conventional methods. IMRT is ideal for treating complex treatment volumes and avoiding close proximity organs at risk that may be dose limiting and provides increased tumour control through an escalated dose and reduces normal tissue complications through organ at risk sparing. Given the potential advantages of IMRT and the availability of IMRT-enabled treatment planning systems and linear accelerators, IMRT has been introduced in a number of disease sites, including prostate cancer. This systematic review examined the evidence for IMRT in the treatment of prostate cancer in order to quantify the potential benefits of this new technology and to make recommendations for radiation treatment programmes considering adopting this technique. The findings were in favour of recommending IMRT over 3DCRT in the radical treatment of localised prostate cancer where doses greater than 70 Gy are required, based on a review of 11 published reports including 4559 patients. There were insufficient data to recommend IMRT over 3DCRT in the postoperative setting. Future research should examine image-guided IMRT in the post-prostatectomy setting, with altered fractionation, and in combination with hormone and chemotherapy.

  18. Diagnosis of colon cancer using frequency domain fluorescence imaging technique

    NASA Astrophysics Data System (ADS)

    Dinish, U. S.; Gulati, P.; Murukeshan, V. M.; Seah, L. K.

    2007-03-01

    Early detection and treatment of colon cancer has been associated with better disease prognosis. Conventional and reported optical techniques have limitations in detecting early stages of colon cancer growth. In this paper, a homodyne signal processing assisted frequency domain (FD) fluorescence imaging methodology is proposed for the early diagnosis of colon cancer. Simulated phantom tissues representing the biopsy samples at different stages of colon cancer growth are prepared and used for the imaging study. Selective imaging of healthy and diseased sites simulated in the samples was achieved even for fluorescence emissions having close lifetimes and wavelength values. Possible extension of the methodology for in vivo investigations is also discussed.

  19. Systems for controlling the intensity variations in a laser beam and for frequency conversion thereof

    DOEpatents

    Skupsky, Stanley; Craxton, R. Stephen; Soures, John

    1990-01-01

    In order to control the intensity of a laser beam so that its intensity varies uniformly and provides uniform illumination of a target, such as a laser fusion target, a broad bandwidth laser pulse is spectrally dispersed spatially so that the frequency components thereof are spread apart. A disperser (grating) provides an output beam which varies spatially in wavelength in at least one direction transverse to the direction of propagation of the beam. Temporal spread (time delay) across the beam is corrected by using a phase delay device (a time delay compensation echelon). The dispersed beam may be amplified with laser amplifiers and frequency converted (doubled, tripled or quadrupled in frequency) with nonlinear optical elements (birefringent crystals). The spectral variation across the beam is compensated by varying the angle of incidence on one of the crystals with respect to the crystal optical axis utilizing a lens which diverges the beam. Another lens after the frequency converter may be used to recollimate the beam. The frequency converted beam is recombined so that portions of different frequency interfere and, unlike interference between waves of the same wavelength, there results an intensity pattern with rapid temoral oscillations which average out rapidly in time thereby producing uniform illumination on target. A distributed phase plate (also known as a random phase mask), through which the spectrally dispersed beam is passed and then focused on a target, is used to provide the interference pattern which becomes nearly modulation free and uniform in intensity in the direction of the spectral variation.

  20. Systems for controlling the intensity variations in a laser beam and for frequency conversion thereof

    DOEpatents

    Skupsky, S.; Craxton, R.S.; Soures, J.

    1990-10-02

    In order to control the intensity of a laser beam so that its intensity varies uniformly and provides uniform illumination of a target, such as a laser fusion target, a broad bandwidth laser pulse is spectrally dispersed spatially so that the frequency components thereof are spread apart. A disperser (grating) provides an output beam which varies spatially in wavelength in at least one direction transverse to the direction of propagation of the beam. Temporal spread (time delay) across the beam is corrected by using a phase delay device (a time delay compensation echelon). The dispersed beam may be amplified with laser amplifiers and frequency converted (doubled, tripled or quadrupled in frequency) with nonlinear optical elements (birefringent crystals). The spectral variation across the beam is compensated by varying the angle of incidence on one of the crystals with respect to the crystal optical axis utilizing a lens which diverges the beam. Another lens after the frequency converter may be used to recollimate the beam. The frequency converted beam is recombined so that portions of different frequency interfere and, unlike interference between waves of the same wavelength, there results an intensity pattern with rapid temporal oscillations which average out rapidly in time thereby producing uniform illumination on target. A distributed phase plate (also known as a random phase mask), through which the spectrally dispersed beam is passed and then focused on a target, is used to provide the interference pattern which becomes nearly modulation free and uniform in intensity in the direction of the spectral variation. 16 figs.

  1. What can the cancer patient expect from intensive meditation?

    PubMed

    Meares, A

    1980-05-01

    The results of treatment of 73 patients with advanced cancer who have been able to attend at least 20 sessions of intensive meditation, indicates that nearly all such patients should expect significant reduction of anxiety and depression, together with much less discomfort and pain. There is reason to expect a ten per cent chance of quite remarkable slowing of the rate of growth of the tumour, and a ten per cent chance of less marked but still significant slowing. The results indicate that patients with advanced cancer have a ten per cent chance of regression of the growth. There is a fifty per cent chance of greatly improved quality of life and for those who die, a ninety per cent chance of death with dignity.

  2. Physical activity and quality of life: assessing the influence of activity frequency, intensity, volume, and motives.

    PubMed

    Lustyk, M Kathleen B; Widman, Laura; Paschane, Amy A E; Olson, Karen C

    2004-01-01

    In the present study, the authors investigated the impact of exercise frequency, intensity, and volume along with exercise motives on quality of life (QOL) reports. The authors assessed exercise habits with the Godin Leisure Time Activity Scale and measured exercise motives with the Reasons for Exercise Inventory. The Quality of Life Inventory assessed satisfaction in 16 domains including health, work, and recreation. High-frequency exercisers reported significantly higher health, helping, and community-related QOL than those who exercised less frequently. The authors noted significantly higher health-related QOL in the heavy volume group compared with the other volume groups. Multiple regression tests revealed that activity intensity and exercise motives significantly predicted QOL reports. The strongest bivariate correlations with QOL existed for mild activity and exercising for fitness and health reasons. Thus, high-frequency activity of mild intensity that produces high kcal utilization and is performed to improve health and fitness has the strongest influence on QOL reports.

  3. Frequency and intensity of palaeofloods at the interface of Atlantic and Mediterranean climate domains

    NASA Astrophysics Data System (ADS)

    Wilhelm, Bruno; Vogel, Hendrik; Crouzet, Christian; Etienne, David; Anselmetti, Flavio S.

    2016-04-01

    The long-term response of the flood activity to both Atlantic and Mediterranean climatic influences was explored by studying a lake sequence (Lake Foréant) of the Western European Alps. High-resolution sedimentological and geochemical analysis revealed 171 event layers, 168 of which result from past flood events over the last millennium. The layer thickness was used as a proxy of intensity of past floods. Because the Foréant palaeoflood record is in agreement with the documented variability of historical floods resulting from local and mesoscale, summer-to-autumn convective events, it is assumed to highlight changes in flood frequency and intensity related to such events typical of both Atlantic (local events) and Mediterranean (meso-scale events) climatic influences. Comparing the Foréant record with other Atlantic-influenced and Mediterranean-influenced regional flood records highlights a common feature in all flood patterns that is a higher flood frequency during the cold period of the Little Ice Age (LIA, AD 1300-1900). In contrast, high-intensity flood events are apparent during both, the cold LIA and the warm Medieval Climate Anomaly (MCA, AD 950-1250). However, there is a tendency towards higher frequencies of high-intensity flood events during the warm MCA. The MCA extremes could mean that under the global warming scenario, we might see an increase in intensity (not in frequency). However, the flood frequency and intensity in course of 20th century warming trend did not change significantly. Uncertainties in future evolution of flood intensity lie in the interpretation of the lack of 20th century extremes (transition or stable?) and the different climate forcing factors between the two periods (greenhouse gases vs. solar/volcanic eruptions).

  4. Frequency and intensity of palaeofloods at the interface of Atlantic and Mediterranean climate domains

    NASA Astrophysics Data System (ADS)

    Wilhelm, B.; Vogel, H.; Crouzet, C.; Etienne, D.; Anselmetti, F. S.

    2016-02-01

    Mediterranean climatic influences was explored by studying a lake sequence (Lake Foréant) of the Western European Alps. High-resolution sedimentological and geochemical analysis revealed 171 event layers, 168 of which result from past flood events over the last millennium. The layer thickness was used as a proxy of intensity of past floods. Because the Foréant palaeoflood record is in agreement with the documented variability of historical floods resulting from local and mesoscale, summer-to-autumn convective events, it is assumed to highlight changes in flood frequency and intensity related to such events typical of both Atlantic (local events) and Mediterranean (mesoscale events) climatic influences. Comparing the Foréant record with other Atlantic-influenced and Mediterranean-influenced regional flood records highlights a common feature in all flood patterns that is a higher flood frequency during the cold period of the Little Ice Age (LIA, AD 1300-1900). In contrast, high-intensity flood events are apparent during both the cold LIA and the warm Medieval Climate Anomaly (MCA, AD 950-1250). However, there is a tendency towards higher frequencies of high-intensity flood events during the warm MCA. The MCA extremes could mean that under the global warming scenario, we might see an increase in intensity (not in frequency). However, the flood frequency and intensity in the course of the 20th century warming trend did not change significantly. Uncertainties in future evolution of flood intensity lie in the interpretation of the lack of 20th century extremes (transition or stable?) and the different climate forcing factors between the two periods (greenhouse gases vs. solar and/or volcanic eruptions).

  5. Intensity discrimination as a function of level and frequency in three species of birds

    NASA Astrophysics Data System (ADS)

    Lauer, Amanda M.; Poling, Kirsten; Dooling, Robert J.

    2003-04-01

    Many studies have examined frequency discrimination in birds, but there has not been as complete a description of avian intensity discrimination abilities. Birds appear to be slightly less sensitive to changes in intensity than humans and other mammals; however, few studies have systematically looked at the effects of both frequency and presentation level on intensity discrimination in birds. Here we describe intensity discrimination as a function of frequency and sensation level in two small songbird species, the canary (Serinus canarius), the zebra finch (Taeniopygia guttata), and a nonsongbird species, the budgerigar (Melopsittacus undulatus). Intensity difference limens (DLIs) for pure tones were obtained from birds using standard operant conditioning procedures and the Method of Constant Stimuli. DLIs ranged from approximately 2-6 dB, which are slightly larger than the DLIs reported in mammals. For all three species, DLIs become smaller with increasing presentation level, but show little effect across frequency for a given level. These results are consistent with previous reports in other species. [Work supported by NIH DC01372 to RJD and DC05450 to AML.

  6. [Application of low-intensity and ultrahigh frequency electromagnetic radiation in modern pediatric practice].

    PubMed

    Azov, N A; Azova, E A

    2009-01-01

    The use of an Amfit-0,2/10-01 apparatus generating low-intensity ultrahigh frequency (UHF) electromagnetic radiation improved efficiency of therapy of sick children. This treatment allowed to reduce the frequency of intake of anesthetics in the post-operative period, correct metabolic disorders in children with type 1 diabetes mellitus, reduce severity of diabetic nephropathy and polyneuropathy, prevent formation of fresh foci of lipoid necrobiosis. The results of the study indicate that the use of low-intensity UHF electromagnetic radiation may be recommended for more extensive introduction into practical clinical work of pediatric endocrinologists and surgeons.

  7. Significant intensity noise suppression of single-frequency fiber laser via cascading semiconductor optical amplifier

    NASA Astrophysics Data System (ADS)

    Feng, Zhouming; Li, Can; Xu, Shanhui; Huang, Xiang; Yang, Changsheng; Zhou, Kaijun; Gan, Jiulin; Deng, Huaqiu; Yang, Zhongmin

    2015-09-01

    Significant suppression of the intensity noise of single-frequency fiber laser is demonstrated with a cascading semiconductor optical amplifier (SOA). Based on the nonlinear amplification dynamics of the SOA, intensity noise reduction would take place in every transmission of the laser signal. By cascading two SOAs, a maximum noise suppression of 30 dB at around the resonant relaxation oscillation (RRO) frequency as well as a suppression bandwidth of up to 50 MHz is realized. Moreover, the RRO peak is restricted to a significant narrow frequency band, outside of which the laser noise approaches the noise floor of the measurement. The remarkable amplified spontaneous emission (ASE) introduced by the SOA is entirely filtered out with a fiber Bragg grating (FBG). Furthermore, no noticeable degradation of laser frequency noise has been observed.

  8. Intratympanic manganese administration revealed sound intensity and frequency dependent functional activity in rat auditory pathway.

    PubMed

    Jin, Seong-Uk; Lee, Jae-Jun; Hong, Kwan Soo; Han, Mun; Park, Jang-Woo; Lee, Hui Joong; Lee, Sangheun; Lee, Kyu-Yup; Shin, Kyung Min; Cho, Jin Ho; Cheong, Chaejoon; Chang, Yongmin

    2013-09-01

    The cochlear plays a vital role in the sense and sensitivity of hearing; however, there is currently a lack of knowledge regarding the relationships between mechanical transduction of sound at different intensities and frequencies in the cochlear and the neurochemical processes that lead to neuronal responses in the central auditory system. In the current study, we introduced manganese-enhanced MRI (MEMRI), a convenient in vivo imaging method, for investigation of how sound, at different intensities and frequencies, is propagated from the cochlear to the central auditory system. Using MEMRI with intratympanic administration, we demonstrated differential manganese signal enhancements according to sound intensity and frequencies in the ascending auditory pathway of the rat after administration of intratympanic MnCl2.Compared to signal enhancement without explicit sound stimuli, auditory structures in the ascending auditory pathway showed stronger signal enhancement in rats who received sound stimuli of 10 and 40 kHz. In addition, signal enhancement with a stimulation frequency of 40 kHz was stronger than that with 10 kHz. Therefore, the results of this study seem to suggest that, in order to achieve an effective response to high sound intensity or frequency, more firing of auditory neurons, or firing of many auditory neurons together for the pooled neural activity is needed.

  9. Intensity-modulated radiotherapy in the treatment of gynaecological cancers.

    PubMed

    D'Souza, D P; Rumble, R B; Fyles, A; Yaremko, B; Warde, P

    2012-09-01

    Intensity-modulated radiotherapy (IMRT) is a newer method of radiotherapy that uses intensity-modulated beams that can provide multiple intensity levels for any single beam direction and any single source position allowing concave dose distributions and dose gradients with narrower margins than those possible using conventional methods. IMRT is ideal for treating complex treatment volumes and avoiding close proximity organs at risk that may be dose limiting and provides increased tumour control through an escalated dose and reduces normal tissue complications through organ at risk sparing. Given the potential advantages of IMRT and the availability of IMRT-enabled treatment planning systems and linear accelerators, IMRT has been introduced in a number of disease sites. This systematic review examined the evidence for IMRT in the treatment of gynaecological cancers to quantify the potential benefits of this new technology and to make recommendations for radiation treatment programmes considering adopting this technique. Findings were based on a review of four cohort studies, one of which was prospective, including a total of 619 patients. If reducing acute and chronic toxicity are the main outcomes of interest, then IMRT may be considered over three-dimensional conformal radiotherapy for women with gynaecological cancers; if disease-related outcomes are the main outcomes of interest, there are insufficient data to recommend IMRT over three-dimensional conformal radiotherapy. Future research should focus on prospective multicentre studies reporting on both acute and chronic toxicity as well as survival and recurrence. Dose escalation studies should be carried out to investigate the effect of higher doses on disease.

  10. Frequency and intensity modulation characteristics of GaAs lasers in an external cavity

    SciTech Connect

    Carter, G.M.; Huang, Kao Yang . Dept. of Electrical Engineering); Brotman, J.; Grober, R.; Mandelberg, H. )

    1993-12-01

    Frequency and intensity modulation characteristics were measured for external cavity GaAs diode lasers as a function of modulation frequency. The data, displayed as a Chirp-to-Power (CPR) ratio, showed at low modulation frequencies a flat response and a zero or 180 degree relative phase depending on laser structure. A model incorporating a carrier density dependent imaginary part of the differential gain (Henry alpha factor) was developed to explain the data. The model yields simple scaling of the CPR with injection current and photon lifetime. The agreement between the model and data including scaling is excellent. These results provide strong evidence for transverse spatial hole burning'' in these lasers.

  11. Rapid skin permeabilization by the simultaneous application of dual-frequency, high-intensity ultrasound.

    PubMed

    Schoellhammer, Carl M; Polat, Baris E; Mendenhall, Jonathan; Maa, Ruby; Jones, Brianna; Hart, Douglas P; Langer, Robert; Blankschtein, Daniel

    2012-10-28

    Low-frequency ultrasound has been studied extensively due to its ability to enhance skin permeability. In spite of this effort, improvements in enhancing the efficacy of transdermal ultrasound treatments have been limited. Currently, when greater skin permeability is desired at a given frequency, one is limited to increasing the intensity or the duration of the ultrasound treatment, which carries the risk of thermal side effects. Therefore, the ability to increase skin permeability without increasing ultrasound intensity or treatment time would represent a significant and desirable outcome. Here, we hypothesize that the simultaneous application of two distinct ultrasound frequencies, in the range of 20 kHz to 3 MHz, can enhance the efficacy of ultrasound exposure. Aluminum foil pitting experiments showed a significant increase in cavitational activity when two frequencies were applied instead of just one low frequency. Additionally, in vitro tests with porcine skin indicated that the permeability and resulting formation of localized transport regions are greatly enhanced when two frequencies (low and high) are used simultaneously. These results were corroborated with glucose (180 Da) and inulin (5000 Da) transdermal flux experiments, which showed greater permeant delivery both into and through the dual-frequency pre-treated skin.

  12. Local frequency estimation from intensity gradients in spatial carrier fringe pattern analysis

    NASA Astrophysics Data System (ADS)

    Zhang, Ruihua; Guo, Hongwei

    2016-06-01

    Spatial carrier fringe pattern analysis is an effective tool in optical measurement, e.g. in interferometry and fringe projection technique. With it, the very large phase deformations in a spatial carrier fringe pattern may increases the bandwidth of fringe component thus leading to difficulties in retrieving its phase map. In order to overcome this problem, many local-adaptive methods have been developed for processing the spatial carrier fringe pattern with large phase variations, and in fact, the local spatial frequency estimation is central to these methods. This paper introduces a simple algorithm for estimating the local frequencies of a fringe pattern with spatial carrier. First, the intensity gradients of the fringe pattern are calculated, and then the standard deviations (SDs) of the intensity gradients at each pixel are estimated from its neighborhood. Finally the local frequencies are estimated from the SDs just calculated simply using an arccosine function. This algorithm is potential in developing effective techniques for retrieving phases from a spatial carrier fringe pattern with large phase variations. For example, we can recover the phase map by directly integrating the local frequencies or by use of an adaptive spatial carrier phase shifting algorithm (SCPS) with the local frequencies being the local phase shifts. It can also be used in Fourier transform method for exactly determining the carrier frequencies, or for extrapolating aperture in order to reduce the boundary effect. Combined with time-frequency techniques such as windowed Fourier transform and wavelet transform methods, it is helpful for alleviating the computational burdens.

  13. Posttraumatic Stress Disorder's Frequency and Intensity Ratings Are Associated with Factor Structure Differences in Military Veterans

    ERIC Educational Resources Information Center

    Elhai, Jon D.; Palmieri, Patrick A.; Biehn, Tracey L.; Frueh, B. Christopher; Magruder, Kathryn M.

    2010-01-01

    We examined possible differences in the factor structure of posttraumatic stress disorder (PTSD) on the basis of whether frequency or intensity symptom response formats were used to assess PTSD. Participants included 669 veterans recruited from an epidemiological study of four Veterans Affairs Medical Centers' primary care clinics in the…

  14. Relationship between Frequency and Intensity of Physical Activity and Health Behaviors of Adolescents

    ERIC Educational Resources Information Center

    Delisle, Tony T.; Werch, Chudley E.; Wong, Alvin H.; Bian, Hui; Weiler, Robert

    2010-01-01

    Background: While studies have determined the importance of physical activity in advancing health outcomes, relatively few have explored the relationship between exercise and various health behaviors of adolescents. The purpose of this study is to examine the relationship between frequency and intensity of physical activity and both health risk…

  15. Trade-off between Intensity and Frequency of Global Tropical Cyclones

    NASA Astrophysics Data System (ADS)

    Kang, N. Y.; Elsner, J.

    2015-12-01

    Global tropical cyclone climate has been investigated with indicators of frequency, intensity and activity. However, a full understanding of global warming's influence on tropical cyclone climate remains elusive because of the incomplete nature of these indicators. Here we form a complete three-dimensional variability space of tropical cyclone climate where the variabilities are continuously linked and find that global ocean warmth best explains the out-of-phase relationship between intensity and frequency of global tropical cyclones. In a year with greater ocean warmth, the tropical troposphere is capped by higher pressure anomaly in the middle and upper troposphere even with higher moist static energy anomaly in the lower troposphere, which is thought to inhibit overall tropical cyclone occurrences but lead to greater intensities. Statistical consequence is the trade-off between intensity and frequency. We calculate an average increase in global tropical cyclone intensity of 1.3 m/s over the past 30 years of ocean warming occurring at the expense of 6.1 tropical cyclones worldwide.

  16. Modeled impact of anthropogenic warming on the frequency of intense Atlantic hurricanes.

    PubMed

    Bender, Morris A; Knutson, Thomas R; Tuleya, Robert E; Sirutis, Joseph J; Vecchi, Gabriel A; Garner, Stephen T; Held, Isaac M

    2010-01-22

    Several recent models suggest that the frequency of Atlantic tropical cyclones could decrease as the climate warms. However, these models are unable to reproduce storms of category 3 or higher intensity. We explored the influence of future global warming on Atlantic hurricanes with a downscaling strategy by using an operational hurricane-prediction model that produces a realistic distribution of intense hurricane activity for present-day conditions. The model projects nearly a doubling of the frequency of category 4 and 5 storms by the end of the 21st century, despite a decrease in the overall frequency of tropical cyclones, when the downscaling is based on the ensemble mean of 18 global climate-change projections. The largest increase is projected to occur in the Western Atlantic, north of 20 degrees N.

  17. Frequency and intensity of palaeofloods at the interface of Atlantic and Mediterranean climate domains

    NASA Astrophysics Data System (ADS)

    Wilhelm, B.; Vogel, H.; Crouzet, C.; Etienne, D.; Anselmetti, F. S.

    2015-10-01

    The long-term response of the flood activity to both Atlantic and Mediterranean climatic influences was explored by studying a lake sequence (Lake Foréant) of the Western European Alps. High-resolution sedimentological and geochemical analysis revealed 171 turbidites, 168 of which result from past flood events over the last millennium. The deposit thickness was used as a proxy of intensity of past floods. Because the Foréant palaeoflood record is in agreement with the documented variability of historical floods resulting from local and mesoscale convective events, it is assumed to highlight changes in flood frequency and intensity related to such events typical of both climatic influences. Comparing the Foréant record with other Atlantic-influenced and Mediterranean-influenced regional flood records highlights a common feature in all flood patterns that is a higher flood frequency during the cold period of the Little Ice Age (LIA). In contrast, high-intensity flood events are apparent during both, the cold LIA and the warm Medieval Climate Anomaly (MCA). However, there is a tendency towards higher frequencies of these events during the warm MCA. The MCA extremes could mean that under the global warming scenario, we might see an increase in intensity (not in frequency). However, the flood frequency and intensity in course of 20th century warming trend did not change significantly. Uncertainties lie in the interpretation of the lack of 20th century extremes (transition or stable?) and the different climate forcing factors (greenhouse gases vs. solar/volcanic eruptions).

  18. TCIQ: An identification by intensity and frequency of potent testing cues in science

    NASA Astrophysics Data System (ADS)

    Kermis, William J.

    Everyone experiences some anxiety while taking an examination. High-test-anxious (HTA) and low-test-anxious (LTA) students are described by two characteristic differences: frequency and intensity of anxious responses and attentional direction to testing cues. The purposes of this study were threefold: (1) to report potent testing cues (i.e., 90% response agreement for both intensity and frequency) that were identified by HTA and LTA students; (2) to report differences between HTA and LTA students for frequencies and intensities of responses to testing cues; and (3) to report differences between HTA and LTA students of attentional direction to testing cues. A pool of 396 males and females who were enrolled in physical geology completed the State-Trait Anxiety Inventory. A random sample consisting of 93 HTA and 40 LTA subjects completed the Test Cues Identification Questionnaire (TCIQ). The TCIQ consists of 28 disruptive items and 27 helpful items. Subjects responded with both frequency and intensity ratings for all of the 55 items in the TCIQ. Results revealed that 22 items were viewed by subjects as potent testing cues. Empirical evidence obtained did not support previous theoretical reports of differences between HTA and LTA students for either frequency and intensity of anxious responses or attentional direction to the set of disruptive and helpful testing cues. Although test anxiousness did not appear to be associated with those two characteristics differences, a discriminant analysis revealed 24 items in the TCIQ which significantly, 2 (24) = 47.59, p < 0.004, separated HTA and LTA subjects responses. Apparently, HTA and LTA students differ in their responses to specific disruptive and helpful cues but not in their responses to the set of testing cues as was previously postulated.

  19. Effects of Stimulus Intensity on Low-Frequency Toneburst Cochlear Microphonic Waveforms

    PubMed Central

    Zhang, Ming

    2013-01-01

    This study investigates changes in amplitude and delays in low-frequency toneburst cochlear microphonic (CM) waveforms recorded at the ear canal in response to different stimulus intensities. Ten volunteers aged 20-30 were recruited. Low-frequency CM waveforms at 500 Hz in response to a 14-ms toneburst were recorded from an ear canal electrode using electrocochleography techniques. The data was statistically analyzed in order to confirm whether the differences were significant in the effects of stimulus intensity on the amplitudes and delays of the low-frequency CM waveforms. Electromagnetic interference artifacts can jeopardize CM measurements but such artifacts can be avoided. The CM waveforms can be recorded at the ear canal in response to a toneburst which is longer than that used in ABR measurements. The CM waveforms thus recorded are robust, and the amplitude of CM waveforms is intensity-dependent. In contrast, the delay of CM waveforms is intensity-independent, which is different from neural responses as their delay or latency is intensity-dependent. These findings may be useful for development of the application of CM measurement as a supplementary approach to otoacoustic emission (OAE) measurement in the clinic which is severely affected by background acoustic noise. The development of the application in the assessment of low-frequency cochlear function may become possible if a further series of studies can verify the feasibility, but it is not meant to be a substitute for audiometry or OAE measurements. The measurement of detection threshold of CM waveform responses using growth function approach may become possible in the clinic. The intensity-independent nature of CMs with regards to delay measurements may also become an impacting factor for differential diagnoses and for designing new research studies. PMID:26557341

  20. Intensity-modulated radiation therapy: supportive data for prostate cancer.

    PubMed

    Cahlon, Oren; Hunt, Margie; Zelefsky, Michael J

    2008-01-01

    Since its introduction into clinical use in the mid-1990s, intensity-modulated radiation therapy (IMRT) has emerged as the most effective and widely used form of external-beam radiotherapy for localized prostate cancer. Multiple studies have confirmed the importance of delivering sufficiently high doses to the prostate to achieve cure. The dosimetric superiority of IMRT over conventional techniques to produce conformal dose distributions that allow for organ sparing has been shown. A growing number of reports have confirmed that IMRT is the safest way to deliver high doses of external-beam irradiation to the prostate and the regional lymph nodes. Advances in imaging and onboard verification systems continue to advance the capabilities of IMRT and have potential implications with regards to further dose escalation and hypofractionated regimens. The clinical data in support of IMRT and the associated technical aspects of IMRT treatment planning and implementation are highlighted in this review.

  1. Differential Influence of Frequency, Timing, and Intensity Cues in a Complex Acoustic Categorization Task

    PubMed Central

    Nagel, Katherine I.; McLendon, Helen M.

    2010-01-01

    Songbirds, which, like humans, learn complex vocalizations, provide an excellent model for the study of acoustic pattern recognition. Here we examined the role of three basic acoustic parameters in an ethologically relevant categorization task. Female zebra finches were first trained to classify songs as belonging to one of two males and then asked whether they could generalize this knowledge to songs systematically altered with respect to frequency, timing, or intensity. Birds' performance on song categorization fell off rapidly when songs were altered in frequency or intensity, but they generalized well to songs that were changed in duration by >25%. Birds were not deaf to timing changes, however; they detected these tempo alterations when asked to discriminate between the same song played back at two different speeds. In addition, when birds were retrained with songs at many intensities, they could correctly categorize songs over a wide range of volumes. Thus although they can detect all these cues, birds attend less to tempo than to frequency or intensity cues during song categorization. These results are unexpected for several reasons: zebra finches normally encounter a wide range of song volumes but most failed to generalize across volumes in this task; males produce only slight variations in tempo, but females generalized widely over changes in song duration; and all three acoustic parameters are critical for auditory neurons. Thus behavioral data place surprising constraints on the relationship between previous experience, behavioral task, neural responses, and perception. We discuss implications for models of auditory pattern recognition. PMID:20610781

  2. Intensity of follow-up after pancreatic cancer resection.

    PubMed

    Castellanos, Jason A; Merchant, Nipun B

    2014-03-01

    The prognosis of patients diagnosed with pancreatic adenocarcinoma remains dismal. Of the 15-20 % of patients who are candidates for potentially curative resection, 66-92 % will develop recurrent disease. Although guidelines for surveillance in the postoperative setting exist, they are not evidence based, and there is wide variability of strategies utilized. Current surveillance guidelines as suggested by the National Comprehensive Cancer Network (NCCN) include routine history and physical, measurement of serum cancer-associated antigen 19-9 (CA19-9) levels, and computed tomographic imaging at 3- to 6-month intervals for the first 2 years, and annually thereafter. However, the lack of prospective clinical data examining the efficacy of different surveillance strategies has led to a variability of the intensity of follow-up and a lack of consensus on its necessity and efficacy. Recent therapeutic advances may have the potential to significantly alter survival after recurrence, but a careful consideration of current surveillance strategies should be undertaken to optimize existing approaches in the face of high recurrence and low survival rates.

  3. A microchip laser source with stable intensity and frequency used for self-mixing interferometry.

    PubMed

    Zhang, Shaohui; Zhang, Shulian; Tan, Yidong; Sun, Liqun

    2016-05-01

    We present a stable 40 × 40 × 30 mm(3) Laser-diode (LD)-pumped-microchip laser (ML) laser source used for self-mixing interferometry which can measure non-cooperative targets. We simplify the coupling process of pump light in order to make its polarization and intensity robust against environmental disturbance. Thermal frequency stabilization technology is used to stabilize the laser frequency of both LD and ML. Frequency stability of about 1 × 10(-7) and short-term intensity fluctuation of 0.1% are achieved. The theoretical long-term displacement accuracy limited by frequency and intensity fluctuation is about 10 nm when the measuring range is 0.1 m. The line-width of this laser is about 25 kHz corresponding to 12 km coherent length and 6 km measurement range for self-mixing interference. The laser source has been equipped to a self-mixing interferometer, and it works very well. PMID:27250399

  4. Dosimetrically Triggered Adaptive Intensity Modulated Radiation Therapy for Cervical Cancer

    SciTech Connect

    Lim, Karen; Stewart, James; Kelly, Valerie; Xie, Jason; Brock, Kristy K.; Moseley, Joanne; Cho, Young-Bin; Fyles, Anthony; Lundin, Anna; Rehbinder, Henrik; Löf, Johan; Jaffray, David A.; Milosevic, Michael

    2014-09-01

    Purpose: The widespread use of intensity modulated radiation therapy (IMRT) for cervical cancer has been limited by internal target and normal tissue motion. Such motion increases the risk of underdosing the target, especially as planning margins are reduced in an effort to reduce toxicity. This study explored 2 adaptive strategies to mitigate this risk and proposes a new, automated method that minimizes replanning workload. Methods and Materials: Thirty patients with cervical cancer participated in a prospective clinical study and underwent pretreatment and weekly magnetic resonance (MR) scans over a 5-week course of daily external beam radiation therapy. Target volumes and organs at risk (OARs) were contoured on each of the scans. Deformable image registration was used to model the accumulated dose (the real dose delivered to the target and OARs) for 2 adaptive replanning scenarios that assumed a very small PTV margin of only 3 mm to account for setup and internal interfractional motion: (1) a preprogrammed, anatomy-driven midtreatment replan (A-IMRT); and (2) a dosimetry-triggered replan driven by target dose accumulation over time (D-IMRT). Results: Across all 30 patients, clinically relevant target dose thresholds failed for 8 patients (27%) if 3-mm margins were used without replanning. A-IMRT failed in only 3 patients and also yielded an additional small reduction in OAR doses at the cost of 30 replans. D-IMRT assured adequate target coverage in all patients, with only 23 replans in 16 patients. Conclusions: A novel, dosimetry-triggered adaptive IMRT strategy for patients with cervical cancer can minimize the risk of target underdosing in the setting of very small margins and substantial interfractional motion while minimizing programmatic workload and cost.

  5. Modeling non-stationarity in intensity, duration and frequency of extreme rainfall over India

    NASA Astrophysics Data System (ADS)

    Mondal, Arpita; Mujumdar, P. P.

    2015-02-01

    Significant changes are reported in extreme rainfall characteristics over India in recent studies though there are disagreements on the spatial uniformity and causes of trends. Based on recent theoretical advancements in the Extreme Value Theory (EVT), we analyze changes in extreme rainfall characteristics over India using a high-resolution daily gridded (1° latitude × 1° longitude) dataset. Intensity, duration and frequency of excess rain over a high threshold in the summer monsoon season are modeled by non-stationary distributions whose parameters vary with physical covariates like the El-Nino Southern Oscillation index (ENSO-index) which is an indicator of large-scale natural variability, global average temperature which is an indicator of human-induced global warming and local mean temperatures which possibly indicate more localized changes. Each non-stationary model considers one physical covariate and the best chosen statistical model at each rainfall grid gives the most significant physical driver for each extreme rainfall characteristic at that grid. Intensity, duration and frequency of extreme rainfall exhibit non-stationarity due to different drivers and no spatially uniform pattern is observed in the changes in them across the country. At most of the locations, duration of extreme rainfall spells is found to be stationary, while non-stationary associations between intensity and frequency and local changes in temperature are detected at a large number of locations. This study presents the first application of non-stationary statistical modeling of intensity, duration and frequency of extreme rainfall over India. The developed models are further used for rainfall frequency analysis to show changes in the 100-year extreme rainfall event. Our findings indicate the varying nature of each extreme rainfall characteristic and their drivers and emphasize the necessity of a comprehensive framework to assess resulting risks of precipitation induced flooding.

  6. [Degranulation of skin mast cells caused by high frequency electromagnetic irradiation of low intensity].

    PubMed

    Popov, V I; Rogachevskiĭ, V V; Gapeev, A B; Khramov, R N; Fesenko, E E

    2001-01-01

    It was shown by light and electron microscopy that local exposure of the projection of the MC-8 lao-gun acupuncture point in rat pad to low-intensity (0.05 mW/cm2) extremely high-frequency (42.0 GHz) electromagnetic radiation caused a degranulation of derma mast cells. It was suggested that the response of skin mast cells is an important amplifying mechanism in the chain of events leading to a systemic response of the organism to low-intensity electromagnetic radiation.

  7. Switching circuit to improve the frequency modulation difference-intensity THz quantum cascade laser imaging

    SciTech Connect

    Saat, N. K.; Dean, P.; Khanna, S. P.; Salih, M.; Linfield, E. H.; Davies, A. G.

    2015-04-24

    We demonstrate new switching circuit for difference-intensity THz quantum cascade laser (QCL) imaging by amplitude modulation and lock in detection. The switching circuit is designed to improve the frequency modulation so that it can stably lock the amplitude modulation of the QCL and the detector output. The combination of a voltage divider and a buffer in switching circuit to quickly switch the amplitude of the QCL biases of 15.8 V and 17.2 V is successfully to increase the frequency modulation up to ∼100 Hz.

  8. Examining Spatio-Temporal Intensity-Frequency Variations in Extreme Monsoon Rainfall using High Resolution Data

    NASA Astrophysics Data System (ADS)

    Devak, M.; Rajendran, V.; C T, D.

    2015-12-01

    The study of extreme events has gained the attention of hydrologists in recent times. Though these events are rare, the effects are catastrophic. It is reported that the frequency of the occurrence of these events has increased in recent decades, and is attributed to the recent revelation of climate change. Numerous studies have pointed out significant changes in extremely heavy precipitation over India, using coarse resolution data. Though there are disagreements in the results and its spatial uniformity, all these studies emphasize the need of fine resolution analysis. Fine resolution analysis is necessary mainly due to the highly heterogeneous characteristics of Indian monsoon, and for the proper employment in flood hazard preparedness and water resources management. The present study aims to analyse the spatio-temporal variation and trends in the intensity and frequency of heavy precipitation during Indian monsoon using 0.25°×0.25° resolution gridded data for a period of 113 years (1901-2013). The exceedance threshold is fixed at 90th percentile of rainfall over 113 years and parameters are defined accordingly. The maximum intensity of each extreme rainfall episode of 30 year moving window has been modelled using Peak Over Threshold based Extreme Value Theory to compute return level (considered for intensity). In addition, the number of such episodes in a particular year has been termed as frequency. Non-parametric Mann-Kendall test has been carried out for both intensity and frequency, to compute the statistical trend. In addition, moving block bootstrap approach has been used to incorporate the serial correlation. The significance of the trend has been evaluated at different significance levels and finally, change in trend over last century has been examined.

  9. Validation of simulated earthquake ground motions based on evolution of intensity and frequency content

    USGS Publications Warehouse

    Rezaeian, Sanaz; Zhong, Peng; Hartzell, Stephen; Zareian, Farzin

    2015-01-01

    Simulated earthquake ground motions can be used in many recent engineering applications that require time series as input excitations. However, applicability and validation of simulations are subjects of debate in the seismological and engineering communities. We propose a validation methodology at the waveform level and directly based on characteristics that are expected to influence most structural and geotechnical response parameters. In particular, three time-dependent validation metrics are used to evaluate the evolving intensity, frequency, and bandwidth of a waveform. These validation metrics capture nonstationarities in intensity and frequency content of waveforms, making them ideal to address nonlinear response of structural systems. A two-component error vector is proposed to quantify the average and shape differences between these validation metrics for a simulated and recorded ground-motion pair. Because these metrics are directly related to the waveform characteristics, they provide easily interpretable feedback to seismologists for modifying their ground-motion simulation models. To further simplify the use and interpretation of these metrics for engineers, it is shown how six scalar key parameters, including duration, intensity, and predominant frequency, can be extracted from the validation metrics. The proposed validation methodology is a step forward in paving the road for utilization of simulated ground motions in engineering practice and is demonstrated using examples of recorded and simulated ground motions from the 1994 Northridge, California, earthquake.

  10. Real-time seismic intensity prediction using frequency-dependent site amplification factors

    NASA Astrophysics Data System (ADS)

    Ogiso, Masashi; Aoki, Shigeki; Hoshiba, Mitsuyuki

    2016-05-01

    A promising approach for the next generation of earthquake early warning system is based on predicting ground motion directly from observed ground motion, without any information of hypocenter. In this study, we predicted seismic intensity at the target stations from the observed ground motion at adjacent stations, employing two different methods of correction for site amplification factors. The first method was frequency-dependent correction prediction, in which we used a digital causal filter to correct the site amplification for the observed waveform in the time domain. The second method was scalar correction, in which we used average differences in seismic intensity between two stations for the site amplification correction. Results from thousands of station pairs that covered almost all of Japan showed that seismic intensity prediction with frequency-dependent correction prediction was more accurate than prediction with scalar correction. Frequency-dependent correction for site amplification in the time domain may lead to more accurate prediction of ground motion in real time.

  11. The negative event scale: measuring frequency and intensity of adult hassles.

    PubMed

    Maybery, D J; Neale, Jason; Arentz, Alex; Jones-Ellis, Jenny

    2007-06-01

    This study examined the structure, concurrent validity, and reliability of a hassle measure for middle-aged adults in both event frequency and intensity recordings. The measure included a range of interpersonal day-to-day events and re-examined aspects of the primary appraisal confounding debate between Lazarus and colleagues (Lazarus, Delongis, Folkman, & Gruen, 1985) and Dohrenwend and Shrout (1985). Of the 373 participants, 73% were female, 72% were in paid work, 69% were in permanent relationships and 62% had children. Principal component analyses of separate hassle frequency and intensity scores highlighted components consistent with previous research. There were seven interpersonal and four non-interpersonal subscales associated with negative events with family and friends, work, health, money, and household. The subscales had very good reliability and concurrent validity and there were generally strong correlations (i.e. up .84) between frequency and intensity scores for each subscale. Given some important sampling limitations (e.g. female overrepresentation) the findings show a psychometrically sound hassle scale for adults. PMID:17999222

  12. Extremely low frequency electromagnetic fields and cancer: The epidemiologic evidence

    SciTech Connect

    Bates, M.N. )

    1991-11-01

    This paper reviews the epidemiologic evidence that low frequency electromagnetic fields generated by alternating current may be cause of cancer. Studies examining residential exposures of children and adults and studies of electrical and electronics workers are reviewed. Using conventional epidemiologic criteria for inferring causal associations, including strength and consistency of the relationship, biological plausibility, and the possibility of bias as an explanation, it is concluded that the evidence is strongly suggestive that such radiation is carcinogenic. The evidence is strongest for brain and central nervous system cancers in electrical workers and children. Weaker evidence supports an association with leukemia in electrical workers. Some evidence also exists for an association with melanoma in electrical workers. Failure to find consistent evidence of a link between residential exposures and adult cancers may be attributable to exposure misclassification. Studies so far have used imperfect surrogates for any true biologically effective magnetic field exposure. The resulting exposure misclassification has produced relative risk estimates that understate any true risk.

  13. Radio Frequency Ultrasound Time Series Signal Analysis to Evaluate High-intensity Focused Ultrasound Lesion Formation Status in Tissue

    PubMed Central

    Mobasheri, Saeedeh; Behnam, Hamid; Rangraz, Parisa; Tavakkoli, Jahan

    2016-01-01

    High-intensity focused ultrasound (HIFU) is a novel treatment modality used by scientists and clinicians in the recent decades. This modality has had a great and significant success as a noninvasive surgery technique applicable in tissue ablation therapy and cancer treatment. In this study, radio frequency (RF) ultrasound signals were acquired and registered in three stages of before, during, and after HIFU exposures. Different features of RF time series signals including the sum of amplitude spectrum in the four quarters of the frequency range, the slope, and intercept of the best-fit line to the entire power spectrum and the Shannon entropy were utilized to distinguish between the HIFU-induced thermal lesion and the normal tissue. We also examined the RF data, frame by frame to identify exposure effects on the formation and characteristics of a HIFU thermal lesion at different time steps throughout the treatment. The results obtained showed that the spectrum frequency quarters and the slope and intercept of the best fit line to the entire power spectrum both increased two times during the HIFU exposures. The Shannon entropy, however, decreased after the exposures. In conclusion, different characteristics of RF time series signal possess promising features that can be used to characterize ablated and nonablated tissues and to distinguish them from each other in a quasi-quantitative fashion. PMID:27186536

  14. Frequency domain approach for time-resolved pump-probe microscopy using intensity modulated laser diodes.

    PubMed

    Miyazaki, J; Kawasumi, K; Kobayashi, T

    2014-09-01

    We present a scheme for time-resolved pump-probe microscopy using intensity modulated laser diodes. The modulation frequencies of the pump and probe beams are varied up to 500 MHz with fixed frequency detuning typically set at 15 kHz. The frequency response of the pump-probe signal is detected using a lock-in amplifier referenced at the beat frequency. This frequency domain method is capable of characterizing the nanosecond to picosecond relaxation dynamics of sample species without the use of a high speed detector or a high frequency lock-in amplifier. Furthermore, as the pump-probe signal is based on the nonlinear interaction between the two laser beams and the sample, our scheme provides better spatial resolution than the conventional diffraction-limited optical microscopes. Time-resolved pump-probe imaging of fluorescence beads and aggregates of quantum dots demonstrates that this method is useful for the microscopic analysis of optoelectronic devices. The system is implemented using compact and low-cost laser diodes, and thus has a broad range of applications in the fields of photochemistry, optical physics, and biological imaging.

  15. Membrane properties specialize mammalian inner hair cells for frequency or intensity encoding

    PubMed Central

    Johnson, Stuart L

    2015-01-01

    The auditory pathway faithfully encodes and relays auditory information to the brain with remarkable speed and precision. The inner hair cells (IHCs) are the primary sensory receptors adapted for rapid auditory signaling, but they are not thought to be intrinsically tuned to encode particular sound frequencies. Here I found that under experimental conditions mimicking those in vivo, mammalian IHCs are intrinsically specialized. Low-frequency gerbil IHCs (~0.3 kHz) have significantly more depolarized resting membrane potentials, faster kinetics, and shorter membrane time constants than high-frequency cells (~30 kHz). The faster kinetics of low-frequency IHCs allow them to follow the phasic component of sound (frequency-following), which is not required for high-frequency cells that are instead optimally configured to encode sustained, graded responses (intensity-following). The intrinsic membrane filtering of IHCs ensures accurate encoding of the phasic or sustained components of the cell’s in vivo receptor potential, crucial for sound localization and ultimately survival. DOI: http://dx.doi.org/10.7554/eLife.08177.001 PMID:26544545

  16. Planck intermediate results. XXII. Frequency dependence of thermal emission from Galactic dust in intensity and polarization

    NASA Astrophysics Data System (ADS)

    Planck Collaboration; Ade, P. A. R.; Alves, M. I. R.; Aniano, G.; Armitage-Caplan, C.; Arnaud, M.; Atrio-Barandela, F.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barreiro, R. B.; Battaner, E.; Benabed, K.; Benoit-Lévy, A.; Bernard, J.-P.; Bersanelli, M.; Bielewicz, P.; Bock, J. J.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Boulanger, F.; Burigana, C.; Cardoso, J.-F.; Catalano, A.; Chamballu, A.; Chiang, H. C.; Colombo, L. P. L.; Combet, C.; Couchot, F.; Coulais, A.; Crill, B. P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R. D.; Davis, R. J.; de Bernardis, P.; de Zotti, G.; Delabrouille, J.; Désert, F.-X.; Dickinson, C.; Diego, J. M.; Donzelli, S.; Doré, O.; Douspis, M.; Dunkley, J.; Dupac, X.; Enßlin, T. A.; Eriksen, H. K.; Falgarone, E.; Finelli, F.; Forni, O.; Frailis, M.; Fraisse, A. A.; Franceschi, E.; Galeotta, S.; Ganga, K.; Ghosh, T.; Giard, M.; González-Nuevo, J.; Górski, K. M.; Gregorio, A.; Gruppuso, A.; Guillet, V.; Hansen, F. K.; Harrison, D. L.; Helou, G.; Hernández-Monteagudo, C.; Hildebrandt, S. R.; Hivon, E.; Hobson, M.; Holmes, W. A.; Hornstrup, A.; Jaffe, A. H.; Jaffe, T. R.; Jones, W. C.; Keihänen, E.; Keskitalo, R.; Kisner, T. S.; Kneissl, R.; Knoche, J.; Kunz, M.; Kurki-Suonio, H.; Lagache, G.; Lamarre, J.-M.; Lasenby, A.; Lawrence, C. R.; Leahy, J. P.; Leonardi, R.; Levrier, F.; Liguori, M.; Lilje, P. B.; Linden-Vørnle, M.; López-Caniego, M.; Lubin, P. M.; Macías-Pérez, J. F.; Maffei, B.; Magalhães, A. M.; Maino, D.; Mandolesi, N.; Maris, M.; Marshall, D. J.; Martin, P. G.; Martínez-González, E.; Masi, S.; Matarrese, S.; Mazzotta, P.; Melchiorri, A.; Mendes, L.; Mennella, A.; Migliaccio, M.; Miville-Deschênes, M.-A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Nati, F.; Natoli, P.; Netterfield, C. B.; Noviello, F.; Novikov, D.; Novikov, I.; Oppermann, N.; Oxborrow, C. A.; Pagano, L.; Pajot, F.; Paoletti, D.; Pasian, F.; Perdereau, O.; Perotto, L.; Perrotta, F.; Piacentini, F.; Pietrobon, D.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Popa, L.; Pratt, G. W.; Rachen, J. P.; Reach, W. T.; Reinecke, M.; Remazeilles, M.; Renault, C.; Ricciardi, S.; Riller, T.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Roudier, G.; Rubiño-Martín, J. A.; Rusholme, B.; Salerno, E.; Sandri, M.; Savini, G.; Scott, D.; Spencer, L. D.; Stolyarov, V.; Stompor, R.; Sudiwala, R.; Sutton, D.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J. A.; Terenzi, L.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Valenziano, L.; Valiviita, J.; Van Tent, B.; Vielva, P.; Villa, F.; Wandelt, B. D.; Zacchei, A.; Zonca, A.

    2015-04-01

    Planck has mapped the intensity and polarization of the sky at microwave frequencies with unprecedented sensitivity. We use these data to characterize the frequency dependence of dust emission. We make use of the Planck 353 GHz I, Q, and U Stokes maps as dust templates, and cross-correlate them with the Planck and WMAP data at 12 frequencies from 23 to 353 GHz, over circular patches with 10° radius. The cross-correlation analysis is performed for both intensity and polarization data in a consistent manner. The results are corrected for the chance correlation between the templates and the anisotropies of the cosmic microwave background. We use a mask that focuses our analysis on the diffuse interstellar medium at intermediate Galactic latitudes. We determine the spectral indices of dust emission in intensity and polarization between 100 and 353 GHz, for each sky patch. Both indices are found to be remarkably constant over the sky. The mean values, 1.59 ± 0.02 for polarization and 1.51 ± 0.01 for intensity, for a mean dust temperature of 19.6 K, are close, but significantly different (3.6σ). We determine the mean spectral energy distribution (SED) of the microwave emission, correlated with the 353 GHz dust templates, by averaging the results of the correlation over all sky patches. We find that the mean SED increases for decreasing frequencies at ν< 60 GHz for both intensity and polarization. The rise of the polarization SED towards low frequencies may be accounted for by a synchrotron component correlated with dust, with no need for any polarization of the anomalous microwave emission. We use a spectral model to separate the synchrotron and dust polarization and to characterize the spectral dependence of the dust polarization fraction. The polarization fraction (p) of the dust emission decreases by (21 ± 6)% from 353 to 70 GHz. We discuss this result within the context of existing dust models. The decrease in p could indicate differences in polarization

  17. Trends in the Annual Frequency of Atlantic Basin Intense Hurricanes: Implications for the Near-Term

    NASA Technical Reports Server (NTRS)

    Wilson, Robert M.

    1998-01-01

    During the interval of 1944-1997, 120 intense hurricanes (category 3, 4, or 5 on the Saffir-Simpson hurricane scale) have been observed in the Atlantic basin. These intense hurricanes have had an observed annual frequency of 0-7 events per year (having a mean, mode, and median equal to about 2 events per year), being preferentially lower during El Ninio years and higher during non-El Ninio years. Also, it has recently been established that a long-term downward trend in the annual frequency of intense hurricanes, spanning about five decades, has taken place, although this trend can, alternatively, be explained as a shift from a more active state prior to the mid 1960's to a less active state thereafter (rather than as a simple linear decline). In this paper, on the basis of 10-yr moving averages, the long4erm trend of the frequency of intense hurricanes is compared against one for the annual mean temperature at Armagh Observatory, Northern Ireland (which serves as a proxy for climatic change). Interestingly, the two sets of 10-yr moving averages correlate extremely well, especially, when incorporating a slight 6-yr lag between them (with temperature leading; r = 0.90). This suggests that the current leading trend of temperature, which had been downward, but now is upward, may portend a return to the more active state for intense hurricanes. Thus, the 1998 season (presuming the abatement of El Ninio prior to the start of the hurricane season), and for several years thereafter (at least, into the early years of the next millennium), may have an annual frequency of intense hurricanes that is commensurate with the previously observed active state that was seen prior to the mid 1960's. If true, then, the shift to the more active state, probably, occurred in the mid-to-late 1980's, apparently, having gone undetected because of the masking, or modulating, effect of El Ninio, which has been rampant since the mid-to-late 1980's.

  18. [Modalities of breast cancer irradiation in 2016: Aims and indications of intensity modulated radiation therapy].

    PubMed

    Bourgier, C; Fenoglietto, P; Lemanski, C; Ducteil, A; Charissoux, M; Draghici, R; Azria, D

    2016-10-01

    Irradiation techniques for breast cancer (arctherapy, tomotherapy) are evolving and intensity-modulated radiation therapy is being increasingly considered for the management of these tumours. Here, we propose a review of intensity-modulated radiation therapy planning issues, clinical toxicities and indications for breast cancer. PMID:27614497

  19. Risk of second cancer from scattered radiation of intensity-modulated radiotherapies with lung cancer

    PubMed Central

    2013-01-01

    Purpose To compare the risk of secondary cancer from scattered and leakage doses following intensity-modulated radiotherapy (IMRT), volumetric arc therapy (VMAT) and tomotherapy (TOMO) in patients with lung cancer. Methods IMRT, VMAT and TOMO were planned for five lung cancer patients. Organ equivalent doses (OEDs) are estimated from the measured corresponding secondary doses during irradiation at various points 20 to 80 cm from the iso-center by using radio-photoluminescence glass dosimeter (RPLGD). Results The secondary dose per Gy from IMRT, VMAT and TOMO for lung cancer, measured 20 to 80 cm from the iso-center, are 0.02~2.03, 0.03~1.35 and 0.04~0.46 cGy, respectively. The mean values of relative OED of secondary dose of VMAT and TOMO, which is normalized by IMRT, ranged between 88.63% and 41.59% revealing 88.63% and 41.59% for thyroid, 82.33% and 41.85% for pancreas, 77.97% and 49.41% for bowel, 73.42% and 72.55% for rectum, 74.16% and 81.51% for prostate. The secondary dose and OED from TOMO became similar to those from IMRT and VMAT as the distance from the field edge increased. Conclusions OED based estimation suggests that the secondary cancer risk from TOMO is less than or comparable to the risks from conventional IMRT and VMAT. PMID:23452670

  20. The body self and the frequency, intensity and acceptance of menopausal symptoms

    PubMed Central

    Wycisk, Jowita

    2015-01-01

    Introduction There are many studies on the concept of body image (usually understood narrowly as body acceptance) in menopausal women, but relationships between the body self and menopausal symptoms have not been explored yet. In the research discussed in this paper, a complex model of the body self, including its functions, body identity and body image, has been presented. Aim of the study Aim of the study was to explore the relationships between different aspects of the body self, and the frequency, intensity and acceptance of menopausal symptoms. Material and methods The investigated sample consisted of 81 women (age: 51.8 ± 4.2 years; range: 45-58 years). The authors used an extended version of the Menopause Symptom List and the Body Self Questionnaire. Results Perception of sensations, interpretation and regulation of emotions and physical states as well as body identity were the most important correlates of the intensity and frequency of menopausal symptoms (psychological, vasomotor and somatic). Among the body image aspects investigated in the study, the appearance evaluation was associated with the frequency of vasomotor and psychological symptoms. The level of acceptance of symptoms was only related to the ability to cope with emotions and physical needs. Conclusions The findings indicate that aspects of the body self (which are stable personality traits) are significant for the way women experience menopausal symptoms. PMID:26327894

  1. Short and Intense Tailor-Made Notched Music Training against Tinnitus: The Tinnitus Frequency Matters

    PubMed Central

    Teismann, Henning; Okamoto, Hidehiko; Pantev, Christo

    2011-01-01

    Tinnitus is one of the most common diseases in industrialized countries. Here, we developed and evaluated a short-term (5 subsequent days) and intensive (6 hours/day) tailor-made notched music training (TMNMT) for patients suffering from chronic, tonal tinnitus. We evaluated (i) the TMNMT efficacy in terms of behavioral and magnetoencephalographic outcome measures for two matched patient groups with either low (≤8 kHz, N = 10) or high (>8 kHz, N = 10) tinnitus frequencies, and the (ii) persistency of the TMNMT effects over the course of a four weeks post-training phase. The results indicated that the short-term intensive TMNMT took effect in patients with tinnitus frequencies ≤8 kHz: subjective tinnitus loudness, tinnitus-related distress, and tinnitus-related auditory cortex evoked activity were significantly reduced after TMNMT completion. However, in the patients with tinnitus frequencies >8 kHz, significant changes were not observed. Interpreted in their entirety, the results also indicated that the induced changes in auditory cortex evoked neuronal activity and tinnitus loudness were not persistent, encouraging the application of the TMNMT as a longer-term training. The findings are essential in guiding the intended transfer of this neuro-scientific treatment approach into routine clinical practice. PMID:21935438

  2. Effect of Herbal Therapy to Intensity Chemotherapy-Induced Nausea and Vomiting in Cancer Patients.

    PubMed Central

    Montazeri, Akram Sadat; Raei, Mehdi; Ghanbari, Atefeh; Dadgari, Ali; Montazeri, Azam Sadat; Hamidzadeh, Azam

    2013-01-01

    Background: Chemotherapy-induced nausea and vomiting are the most important complications for cancer patients as its prevalence has been reported to be about 54-96 percent. ginger has been used for medicinal purposes including nausea and vomiting in traditional Persian, Chinese and Indian pharmacopoeia. Objectives: The objective of this study was to evaluate the efficacy of complimentary ginger among cancer patients experiencing nausea and vomiting. Material and Methods: A randomized cross-over clinical trial was carried out on patients under chemotherapy treatment for at least 2 episodes of chemotherapy and at least 2 episodes of previous experience of nausea and vomiting. Subjects of this study received 2 different complementary regimes with 250mg ginger capsule in regime A and placebo capsule in regime B. subjects of the study were crossed over to receive the other regime during the two cycles of chemotherapy. Results: Findings of the study indicated that subjects receiving ginger showed significant reduction in frequency and intensity of nausea and vomiting compared to placebo receiving subjects. Conclusions: According to finding of this study, in accordance to most of other researches, ginger is an effective agent to reduce chemotherapy-induced nausea and vomiting. However, there are some researches supporting ginger as a moderate antiemetic agent among cancerous patients under chemotherapy. PMID:24693415

  3. A Simplified Instrument for Recording and Indicating Frequency and Intensity of Icing Conditions Encountered in Flight

    NASA Technical Reports Server (NTRS)

    Perkins, Porter J; Mccullough, Stuart; Lewis, Ralph D

    1951-01-01

    An instrument for recording and indicating the frequency and intensity of aircraft icing conditions encountered in flight has been developed by the NACA Lewis Laboratory to obtain statistical icing data over world-wide air routes during routine airline operations. The operation of the instrument is based on the creation of a differential pressure between an ice-free total-pressure system and a total-pressure system in which small total-pressure holes vented to static pressure are allowed to plug with ice accretion. The simplicity of this operating principle permits automatic operation, and provides relative freedom from maintenance and operating problems. The complete unit weighing only 18 pounds records icing rate, airspeed, and altitude on photographic film and provides visual indications of icing intensity to the pilot.

  4. Cell-stimulation therapy of lateral epicondylitis with frequency-modulated low-intensity electric current.

    PubMed

    Aliyev, R M; Geiger, G

    2012-03-01

    In addition to the routine therapy, the patients with lateral epicondylitis included into experimental group were subjected to a 12-week cell-stimulation therapy with low-intensity frequency-modulated electric current. The control group received the same routine therapy and sham stimulation (the therapeutic apparatus was not energized). The efficiency of this microcurrent therapy was estimated by comparing medical indices before therapy and at the end of a 12-week therapeutic course using a 10-point pain severity numeric rating scale (NRS) and Roles-Maudsley pain score. The study revealed high therapeutic efficiency of cell-stimulation with low-intensity electric current resulting probably from up-regulation of intracellular transmitters, interleukins, and prostaglandins playing the key role in the regulation of inflammation.

  5. Development of Intensity-Duration-Frequency curves at ungauged sites: risk management under changing climate

    NASA Astrophysics Data System (ADS)

    Liew, San Chuin; Raghavan, Srivatsan V.; Liong, Shie-Yui

    2014-12-01

    The impact of a changing climate is already being felt on several hydrological systems both on a regional and sub-regional scale of the globe. Southeast Asia is one of the regions strongly affected by climate change. With climate change, one of the anticipated impacts is an increase in the intensity and frequency of extreme rainfall which further increase the region's flood catastrophes, human casualties and economic loss. Optimal mitigation measures can be undertaken only when stormwater systems are designed using rainfall Intensity-Duration-Frequency (IDF) curves derived from a long and good quality rainfall data. Developing IDF curves for the future climate can be even more challenging especially for ungauged sites. The current practice to derive current climate's IDF curves for ungauged sites is, for example, to `borrow' or `interpolate' data from regions of climatologically similar characteristics. Recent measures to derive IDF curves for present climate was performed by extracting rainfall data from a high spatial resolution Regional Climate Model driven by ERA-40 reanalysis dataset. This approach has been demonstrated on an ungauged site (Java, Indonesia) and the results were quite promising. In this paper, the authors extend the application of the approach to other ungauged sites particularly in Peninsular Malaysia. The results of the study undoubtedly have significance contribution in terms of local and regional hydrology (Malaysia and Southeast Asian countries). The anticipated impacts of climate change especially increase in rainfall intensity and its frequency appreciates the derivation of future IDF curves in this study. It also provides policy makers better information on the adequacy of storm drainage design, for the current climate at the ungauged sites, and the adequacy of the existing storm drainage to cope with the impacts of climate change.

  6. Multiphoton Absorption by Helium, Magnesium and H2 at High Frequencies and Intensities

    NASA Astrophysics Data System (ADS)

    Taylor, K. T.

    We review principally some recent work carried out in Belfast and Heraklion which handles the few-electron dynamics of atomic and molecular systems exposed to high frequency, high intensity laser fields. The design and application of the quantitatively accurate computational methods is discussed. The Belfast work is illustrated by results for double ionization of helium and the hydrogen molecule where in each case the two electrons have been handled in full-dimensionality. The first results for multiphoton, double ionization of a complex atom, namely magnesium demonstrate an important application of the Heraklion approach.

  7. Self-focusing of intense high frequency electromagnetic waves in a collisional magnetoactive plasma

    SciTech Connect

    Niknam, A. R.; Hashemzadeh, M.; Aliakbari, A.; Majedi, S.; Haji Mirzaei, F.

    2011-11-15

    The self-focusing of an intense electromagnetic beam in a collisional magnetoactive plasma has been investigated by the perturbation method. Considering the relativistic and ponderomotive nonlinearities and the first three terms of perturbation expansion for the electron density and velocity, the nonlinear wave equation is obtained. This wave equation is solved by applying the source dependent expansion method and the evolution of electromagnetic beam spot-size is discussed. It is shown that the laser spot-size decreases with increasing the collision frequency and external magnetic field strength.

  8. Rigorous intensity and phase-shift manipulation in optical frequency conversion.

    PubMed

    Yang, Bo; Yue, Yang-Yang; Lu, Rong-Er; Hong, Xu-Hao; Zhang, Chao; Qin, Yi-Qiang; Zhu, Yong-Yuan

    2016-01-01

    A simple method is employed to investigate the nonlinear frequency conversion in optical superlattices (OSL) with pump depletion. Four rigorous phase-matching conditions for different purposes are obtained directly from the nonlinear coupled equations, and the resulting OSL domain structures are generally aperiodic rather than periodic. With this method, not only the intensity but also the phase-shift of the harmonic waves can be manipulated at will. The second-harmonic generation of Gaussian beam is further investigated. This work may provide a guidance for the practical applications of designing nonlinear optical devices with high conversion efficiency. PMID:27272308

  9. Rigorous intensity and phase-shift manipulation in optical frequency conversion

    NASA Astrophysics Data System (ADS)

    Yang, Bo; Yue, Yang-Yang; Lu, Rong-Er; Hong, Xu-Hao; Zhang, Chao; Qin, Yi-Qiang; Zhu, Yong-Yuan

    2016-06-01

    A simple method is employed to investigate the nonlinear frequency conversion in optical superlattices (OSL) with pump depletion. Four rigorous phase-matching conditions for different purposes are obtained directly from the nonlinear coupled equations, and the resulting OSL domain structures are generally aperiodic rather than periodic. With this method, not only the intensity but also the phase-shift of the harmonic waves can be manipulated at will. The second-harmonic generation of Gaussian beam is further investigated. This work may provide a guidance for the practical applications of designing nonlinear optical devices with high conversion efficiency.

  10. A statistical analysis of the association between tropical cyclone intensity change and tornado frequency

    NASA Astrophysics Data System (ADS)

    Moore, Todd W.

    2016-07-01

    Tropical cyclones often produce tornadoes that have the potential to compound the injury and fatality counts and the economic losses associated with tropical cyclones. These tornadoes do not occur uniformly through time or across space. Multiple statistical methods were used in this study to analyze the association between tropical cyclone intensity change and tornado frequency. Results indicate that there is an association between the two and that tropical cyclones tend to produce more tornadoes when they are weakening, but the association is weak. Tropical cyclones can also produce a substantial number of tornadoes when they are relatively stable or strengthening.

  11. Rigorous intensity and phase-shift manipulation in optical frequency conversion

    PubMed Central

    Yang, Bo; Yue, Yang-Yang; Lu, Rong-er; Hong, Xu-Hao; Zhang, Chao; Qin, Yi-Qiang; Zhu, Yong-Yuan

    2016-01-01

    A simple method is employed to investigate the nonlinear frequency conversion in optical superlattices (OSL) with pump depletion. Four rigorous phase-matching conditions for different purposes are obtained directly from the nonlinear coupled equations, and the resulting OSL domain structures are generally aperiodic rather than periodic. With this method, not only the intensity but also the phase-shift of the harmonic waves can be manipulated at will. The second-harmonic generation of Gaussian beam is further investigated. This work may provide a guidance for the practical applications of designing nonlinear optical devices with high conversion efficiency. PMID:27272308

  12. The Safety of Using High Frequency, Low Intensity Ultrasound to Enhance Thrombolysis

    SciTech Connect

    Soltani, Azita

    2006-05-08

    The EKOS Ultrasound Infusion Systems (EKOS Corporation, Bothell, WA) use high frequency, low intensity ultrasound to accelerate thrombolysis by enhancing clot permeability and lytic drug penetration into thrombus. These systems are designed to provide efficacious catheter-directed treatment for the management of stroke, peripheral arterial occlusion and deep vein thrombosis. The in vitro and in vivo results of investigating the stability of therapeutic and diagnostic compounds used in combination with EKOS devices, the potential for adverse biological effects and the clot fragmentation confirmed the safety of EKOS ultrasound infusion systems in thrombolysis treatment.

  13. The Safety of Using High Frequency, Low Intensity Ultrasound to Enhance Thrombolysis

    NASA Astrophysics Data System (ADS)

    Soltani, Azita

    2006-05-01

    The EKOS Ultrasound Infusion Systems (EKOS Corporation, Bothell, WA) use high frequency, low intensity ultrasound to accelerate thrombolysis by enhancing clot permeability and lytic drug penetration into thrombus. These systems are designed to provide efficacious catheter-directed treatment for the management of stroke, peripheral arterial occlusion and deep vein thrombosis. The in vitro and in vivo results of investigating the stability of therapeutic and diagnostic compounds used in combination with EKOS devices, the potential for adverse biological effects and the clot fragmentation confirmed the safety of EKOS ultrasound infusion systems in thrombolysis treatment.

  14. Perturbative approach in the frequency domain for the intensity correlation spectrum in electromagnetically induced transparency

    NASA Astrophysics Data System (ADS)

    Florez, H. M.; González, C.; Martinelli, M.

    2016-07-01

    Correlation spectroscopy has been proposed as a spectroscopic technique for measuring the coherence between the ground states in electromagnetically induced transparency (EIT). While in the time domain the steep dispersion in the EIT condition accounts for the robustness of the correlation linewidth against power broadening, such physical insight was not directly established in the frequency domain. We propose a perturbative approach to describe the correlation spectroscopy of two noisy lasers coupled to a Λ transition in cold atoms, leading to EIT. Such approach leads to an analytical expression that maps the intensity correlation directly in terms of the absorption and dispersion of the light fields. Low and high perturbative regimes are investigated and demonstrate that, for coherent light sources, the first-order term in perturbation expansion represents a sufficient description for the correlation. Sideband resonances are also observed, showing the richness of the frequency domain approach.

  15. Intensity and Timing in Life of Recreational Physical Activity in Relation to Breast Cancer Risk Among Pre- and Postmenopausal Women

    PubMed Central

    2010-01-01

    Regular recreational physical activity has been found to be associated with a decrease in breast cancer risk in women in the majority of epidemiologic studies, but research findings are inconsistent regarding the intensity of activity and timing in life. To address these issues the relations of moderate and vigorous intensity recreational physical activity during ages 14-20, 21-34, 35-50, and over age 50 years to pre- and postmenopausal breast cancer risk were examined. A case-control study of 858 women, with histological confirmation of invasive breast cancer, and 1085 controls, free of any cancer diagnosis, all subjects aged 28-79 years was conducted in the Region of Western Pomerania (Poland). Physical activity was assessed using a self-administered questionnaire with questions on type of activity, duration, frequency, and intensity for each type of activity. Odds ratios (OR) and 95% confidence intervals (CI) of breast cancer associated with physical activity were calculated using unconditional logistic regression. Vigorous physical activity at ages 14-20 and 21-34 years lowered breast cancer risk by at least 35% in premenopausal women and by at least 51% in postmenopausal women for the highest versus lowest quartiles of the activity. The risk was also reduced in postmenopausal women who reported on average more than 1.74 hours per week of vigorous intensity recreational activity in ages >50 years (OR = 0.58; 95%CI = 0.27-0.97; P for trend = 0.013). For moderate activity the relationships remained statistically significant only in postmenopausal women active during ages 14- 20 years. The results indicate also a plausible risk reduction among premeno-pausal women. These results support the hypothesis that recrea-tional activity, particularly done early in life, is associated with a decrease in the invasive breast cancer risk in postmenopausal women. Among premenopausal women, only vigorous forms of activity may significantly decrease the risk. Key points

  16. Frequencies of poor metabolizers of cytochrome P450 2C19 in esophagus cancer, stomach cancer, lung cancer and bladder cancer in Chinese population

    PubMed Central

    Shi, Wei-Xing; Chen, Shu-Qing

    2004-01-01

    AIM: To investigate the association between cytochrome P450 2C19 (CYP2C19) gene polymorphism and cancer susceptibility by genotyping of CYP2C19 poor metabolizers (PMs) in cancer patients. METHODS: One hundred and thirty-five cases of esophagus cancer, 148 cases of stomach cancer, 212 cases of lung cancer, 112 cases of bladder cancer and 372 controls were genotyped by allele specific amplification-polymerase chain reaction (ASA-PCR) for CYP2C19 PMs. The frequencies of PMs in cancer groups and control group were compared. RESULTS: The frequencies of PMs of CYP2C19 were 34.1% (46/135) in the group of esophagus cancer patients, 31.8% (47/148) in the stomach cancer patients, 34.4% (73/212) in the group of lung cancer patients, only 4.5% (5/112) in the bladder cancer patients and 14.0% (52/372) in control group. There were statistical differences between the cancer groups and control group (esophagus cancer, χ2 = 25.65, P < 0.005, OR = 3.18, 95%CI = 2.005-5.042; stomach cancer, χ2 = 21.70, P < 0.005, OR = 2.86, 95%CI = 1.820-4.501; lung cancer, χ2 = 33.58, P < 0.005, OR = 3.23, 95%CI = 1.503-6.906; bladder cancer, χ2 = 7.50, P < 0.01, OR = 0.288, 95%CI = 0.112-0.740). CONCLUSION: CYP2C19 PMs have a high incidence of esophagus cancer, stomach cancer and lung cancer, conversely they have a low incidence of bladder cancer. It suggests that CYP2C19 may participate in the activation of procarcinogen of esophagus cancer, stomach cancer and lung cancer, but may involve in the detoxification of carcinogens of bladder cancer. PMID:15222046

  17. A method for estimating the intensity of overdominant selection from the distribution of allele frequencies.

    PubMed Central

    Slatkin, M; Muirhead, C A

    2000-01-01

    A method is proposed for estimating the intensity of overdominant selection scaled by the effective population size, S = 2Ns, from allele frequencies. The method is based on the assumption that, with strong overdominant selection, allele frequencies are nearly at their deterministic equilibrium values and that, to a first approximation, deviations depend only on S. Simulations verify that reasonably accurate estimates of S can be obtained for realistic sample sizes. The method is applied to data from several loci in the major histocompatibility complex (Mhc) in numerous human populations. For alleles distinguished by both serological typing and the sequence of the peptide-binding region, our estimates of S are comparable to those obtained by analysis of DNA sequences in showing that selection is strongest on HLA-B and weaker on HLA-A, HLA-DRB1, and HLA-DQA1. The intensity of selection on HLA-B varied considerably among populations. Two populations, Native American and Inuit, showed an excess rather than a deficiency in homozygosity. Comparable estimates of S were obtained for alleles at Mhc class II loci distinguished by serological reactions (serotyping) and by differences in the amino acid sequences of the peptide-binding region (molecular typing). A comparison of two types of data for DQA1 and DRB1 showed that serotyping led to generally lower estimates of S. PMID:11102400

  18. The Interannual Stability of Cumulative Frequency Distributions for Convective System Size and Intensity

    NASA Technical Reports Server (NTRS)

    Mohr, Karen I.; Molinari, John; Thorncroft, Chris D,

    2010-01-01

    The characteristics of convective system populations in West Africa and the western Pacific tropical cyclone basin were analyzed to investigate whether interannual variability in convective activity in tropical continental and oceanic environments is driven by variations in the number of events during the wet season or by favoring large and/or intense convective systems. Convective systems were defined from TRMM data as a cluster of pixels with an 85 GHz polarization-corrected brightness temperature below 255 K and with an area at least 64 km 2. The study database consisted of convective systems in West Africa from May Sep for 1998-2007 and in the western Pacific from May Nov 1998-2007. Annual cumulative frequency distributions for system minimum brightness temperature and system area were constructed for both regions. For both regions, there were no statistically significant differences among the annual curves for system minimum brightness temperature. There were two groups of system area curves, split by the TRMM altitude boost in 2001. Within each set, there was no statistically significant interannual variability. Sub-setting the database revealed some sensitivity in distribution shape to the size of the sampling area, length of sample period, and climate zone. From a regional perspective, the stability of the cumulative frequency distributions implied that the probability that a convective system would attain a particular size or intensity does not change interannually. Variability in the number of convective events appeared to be more important in determining whether a year is wetter or drier than normal.

  19. Intensity statistics of very high frequency sound scattered from wind-driven waves.

    PubMed

    Walstead, Sean P; Deane, Grant B

    2016-05-01

    The interaction of vhf 100-1000 kHz underwater sound with the ocean surface is explored. The bistatic forward scatter of 300 kHz sound is measured in a wind driven wave channel. Fluctuations in arrival amplitude are described by the scintillation index (SI) which is a measure of arrival intensity variance. SI initially increases with wind speed but eventually saturates to a value of 0.5 when the root-mean-square (rms) roughness is 0.5 mm. An adjusted scintillation index (SI*) is suggested that accounts for the multiple arrivals and properly saturates to a value of 1. Fluctuations in arrival time do not saturate and increase proportionately to the dominant surface wave component. Forward scattering is modeled at frequencies ranging from 50 to 2000 kHz using the Helmholtz-Kirchhoff integral with surface wave realizations derived from wave gauge data. The amplitude and temporal statistics of the simulated scattering agree well with measured data. Intensity saturation occurs at lower wind speeds for higher frequency sound. Both measured and modeled vhf sound is characterized by many surface arrivals at saturation. Doppler shifts associated with wave motion are expected to vary rapidly for vhf sound however further analysis is required.

  20. Intensity statistics of very high frequency sound scattered from wind-driven waves.

    PubMed

    Walstead, Sean P; Deane, Grant B

    2016-05-01

    The interaction of vhf 100-1000 kHz underwater sound with the ocean surface is explored. The bistatic forward scatter of 300 kHz sound is measured in a wind driven wave channel. Fluctuations in arrival amplitude are described by the scintillation index (SI) which is a measure of arrival intensity variance. SI initially increases with wind speed but eventually saturates to a value of 0.5 when the root-mean-square (rms) roughness is 0.5 mm. An adjusted scintillation index (SI*) is suggested that accounts for the multiple arrivals and properly saturates to a value of 1. Fluctuations in arrival time do not saturate and increase proportionately to the dominant surface wave component. Forward scattering is modeled at frequencies ranging from 50 to 2000 kHz using the Helmholtz-Kirchhoff integral with surface wave realizations derived from wave gauge data. The amplitude and temporal statistics of the simulated scattering agree well with measured data. Intensity saturation occurs at lower wind speeds for higher frequency sound. Both measured and modeled vhf sound is characterized by many surface arrivals at saturation. Doppler shifts associated with wave motion are expected to vary rapidly for vhf sound however further analysis is required. PMID:27250171

  1. [Polish guidelines of 2001 for maximum admissible intensities in high frequency EMF versus European Union recommendations].

    PubMed

    Aniołczyk, Halina

    2003-01-01

    In 1999, a draft of amendments to maximum admissible intensities (MAI) of electromagnetic fields (0 Hz-300 GHz) was prepared by Professor H. Korniewicz of the Central Institute for Labour Protection, Warsaw, in cooperation with the Nofer Institute of Occupational Medicine, Łódź (radio- and microwaves) and the Military Institute of Hygiene and Epidemiology, Warsaw (pulse radiation). Before 2000, the development of the national MAI guidelines for the frequency range of 0.1 MHz-300 GHz was based on the knowledge of biological and health effects of EMF exposure available on the turn of the 1960s. A current basis for establishing the MAI international standards is a well-documented thermal effect measured by the value of a specific absorption rate (SAR), whereas the effects of resonant absorption imposes the nature of the functional dependency on EMF frequency. The Russian standards, already thoroughly analyzed, still take so-called non-thermal effects and the conception of energetic load for a work-shift with its progressive averaging (see hazardous zone in Polish guidelines) as a basis for setting maximum admissible intensities. The World Health Organization recommends a harmonization of the EMF protection guidelines, existing in different countries, with the guidelines of the International Commission for Non-Ionizing Radiation Protection (ICNIRP), and its position is supported by the European Union.

  2. High-frequency ultrasound imaging for breast cancer biopsy guidance.

    PubMed

    Cummins, Thomas; Yoon, Changhan; Choi, Hojong; Eliahoo, Payam; Kim, Hyung Ham; Yamashita, Mary W; Hovanessian-Larsen, Linda J; Lang, Julie E; Sener, Stephen F; Vallone, John; Martin, Sue E; Kirk Shung, K

    2015-10-01

    Image-guided core needle biopsy is the current gold standard for breast cancer diagnosis. Microcalcifications, an important radiographic finding on mammography suggestive of early breast cancer such as ductal carcinoma in situ, are usually biopsied under stereotactic guidance. This procedure, however, is uncomfortable for patients and requires the use of ionizing radiation. It would be preferable to biopsy microcalcifications under ultrasound guidance since it is a faster procedure, more comfortable for the patient, and requires no radiation. However, microcalcifications cannot reliably be detected with the current standard ultrasound imaging systems. This study is motivated by the clinical need for real-time high-resolution ultrasound imaging of microcalcifications, so that biopsies can be accurately performed under ultrasound guidance. We have investigated how high-frequency ultrasound imaging can enable visualization of microstructures in ex vivo breast tissue biopsy samples. We generated B-mode images of breast tissue and applied the Nakagami filtering technique to help refine image output so that microcalcifications could be better assessed during ultrasound-guided core biopsies. We describe the preliminary clinical results of high-frequency ultrasound imaging of ex vivo breast biopsy tissue with microcalcifications and without Nakagami filtering and the correlation of these images with the pathology examination by hematoxylin and eosin stain and whole slide digital scanning. PMID:26693167

  3. The BDNF Val66Met Polymorphism Modulates Sleep Intensity: EEG Frequency- and State-Specificity

    PubMed Central

    Bachmann, Valérie; Klein, Carina; Bodenmann, Sereina; Schäfer, Nikolaus; Berger, Wolfgang; Brugger, Peter; Landolt, Hans-Peter

    2012-01-01

    Study Objectives: EEG slow waves are the hallmark of deep NREM sleep and may reflect the restorative functions of sleep. Evidence suggests that increased sleep slow waves after sleep deprivation reflect plastic synaptic processes, and that brain-derived neurotrophic factor (BDNF) is causally involved in their homeostatic regulation. The functional Val66Met polymorphism of the gene encoding pro-BDNF causes impaired activity-dependent secretion of mature BDNF protein. We investigated whether this polymorphism contributes to the pronounced inter-individual variation in sleep slow wave activity (SWA) in humans. Setting: Sleep laboratory in temporal isolation unit. Participants: Eleven heterozygous Met allele carriers and 11 individually sex- and age-matched Val/Val homozygotes. Interventions: Forty hours prolonged wakefulness. Measurements and Results: Cognitive performance, subjective state, and waking and sleep EEG in baseline and after sleep deprivation were studied. Val/Val homozygotes showed better response accuracy than Met allele carriers on a verbal 2-back working memory task. This difference did not reflect genotype-dependent differences in sleepiness, well-being, or sustained attention. In baseline and recovery nights, deep stage 4 sleep and NREM sleep intensity as quantified by EEG SWA (0.75-4.5 Hz) were higher in Val/Val compared to Val/Met genotype. Similar to sleep deprivation, the difference was most pronounced in the first NREM sleep episode. By contrast, increased activity in higher EEG frequencies (> 6 Hz) in wakefulness and REM sleep was distinct from the effects of prolonged wakefulness. Conclusion: BDNF contributes to the regulation of sleep slow wave oscillations, suggesting that genetically determined variation in neuronal plasticity modulates NREM sleep intensity in humans. Citation: Bachmann V; Klein C; Bodenmann S; Schäfer N; Berger W; Brugger P; Landolt HP. The BDNF Val66Met polymorphism modulates sleep intensity: EEG frequency- and state

  4. Rainfall Intensity Estimation by Ground-Based Dual-Frequency Microwave Radiometers.

    NASA Astrophysics Data System (ADS)

    Liu, Gin-Rong; Liu, Chung-Chih; Kuo, Tsung-Hua

    2001-06-01

    Many investigators have used satellite data to derive rainfall intensity and to compare them with rain gauge data. However, there has always been a problem: what is the optimal time period for the two different types of data? A set of well-controlled data collected by ground-based dual-frequency microwave radiometers at the National Central University (24.9°N, 121.1°E) in Taiwan between January of 1996 and December of 1997 was used to find the answer. The results show that a 1-h interval would be the optimal time period and that hourly data will provide a better accuracy than other options (5, 10, or 30 min or 2 h). Two algorithms, the differential and the brightness temperature, were established to estimate rainfall intensity using ground-based dual-frequency microwave brightness temperature and rain gauge data. The results show that the root-mean-square error and the correlation coefficient are 0.63 mm h1 and 0.88, respectively, for the differential method, and 0.91 mm h1 and 0.71 for the brightness temperature method. The analysis also shows that because the atmospheric background and environmental influence in the continuous observations are identical, the changes in brightness temperature are only caused from the changes in liquid water content in the air. That probably made the differential method a better choice for rainfall intensity estimation than the brightness temperature method. Moreover, ground-based radiometers measure downwelling radiation from bottom up, and little ice-particle scattering or horizontal inhomogeneity is involved. The results can be compared with retrievals from satellite microwave radiometers for a better understanding of the physics of microwave emission and scattering due to raindrops or ice particles.

  5. Effects of Disturbance Intensity and Frequency on Bacterial Community Composition and Function

    PubMed Central

    Berga, Mercè; Székely, Anna J.; Langenheder, Silke

    2012-01-01

    Disturbances influence community structure and ecosystem functioning. Bacteria are key players in ecosystems and it is therefore crucial to understand the effect of disturbances on bacterial communities and how they respond to them, both compositionally and functionally. The main aim of this study was to test the effect of differences in disturbance strength on bacterial communities. For this, we implemented two independent short-term experiments with dialysis bags containing natural bacterial communities, which were transplanted between ambient and ‘disturbed’ incubation tanks, manipulating either the intensity or the frequency of a salinity disturbance. We followed changes in community composition by terminal restriction fragment analysis (T-RFLP) and measured various community functions (bacterial production, carbon substrate utilization profiles and rates) directly after and after a short period of recovery under ambient conditions. Increases in disturbance strength resulted in gradually stronger changes in bacterial community composition and functions. In the disturbance intensity experiment, the sensitivity to the disturbance and the ability of recovery differed between different functions. In the disturbance frequency experiment, effects on the different functions were more consistent and recovery was not observed. Moreover, in case of the intensity experiment, there was also a time lag in the responses of community composition and functions, with functional responses being faster than compositional ones. To summarize, our study shows that disturbance strength has the potential to change the functional performance and composition of bacterial communities. It further highlights that the overall effects, rates of recovery and the degree of congruence in the response patterns of community composition and functioning along disturbance gradients depend on the type of function and the character of the disturbance. PMID:22606316

  6. Simulation of reflected light intensity changes during navigation and radio-frequency lesioning in the brain.

    PubMed

    Johansson, Johannes D; Fredriksson, Ingemar; Wårdell, Karin; Eriksson, Ola

    2009-01-01

    An electrode with adjacent optical fibers for measurements during navigation and radio frequency lesioning in the brain is modeled for Monte Carlo simulations of light transport in brain tissue. Relative reflected light intensity at 780 nm, I780, from this electrode and probes with identical fiber configuration are simulated using the intensity from native white matter as reference. Models are made of homogeneous native and coagulated gray, thalamus, and white matter as well as blood. Dual layer models, including models with a layer of cerebrospinal fluid between the fibers and the brain tissue, are also made. Simulated I780 was 0.16 for gray matter, 0.67 for coagulate gray matter, 0.36 for thalamus, 0.39 for coagulated thalamus, unity for white matter, 0.70 for coagulated white matter, and 0.24 for blood. Thalamic matter is also found to reflect more light than gray matter and less than white matter in clinical studies. In conclusion, the reflected light intensity can be used to differentiate between gray and white matter during navigation. Furthermore, coagulation of light gray tissue, such as the thalamus, might be difficult to detect using I780, but coagulation in darker gray tissue should result in a rapid increase of I780.

  7. Simulation of reflected light intensity changes during navigation and radio-frequency lesioning in the brain

    NASA Astrophysics Data System (ADS)

    Johansson, Johannes D.; Fredriksson, Ingemar; Wa˚Rdell, Karin; Eriksson, Ola

    2009-07-01

    An electrode with adjacent optical fibers for measurements during navigation and radio frequency lesioning in the brain is modeled for Monte Carlo simulations of light transport in brain tissue. Relative reflected light intensity at 780 nm, I780, from this electrode and probes with identical fiber configuration are simulated using the intensity from native white matter as reference. Models are made of homogeneous native and coagulated gray, thalamus, and white matter as well as blood. Dual layer models, including models with a layer of cerebrospinal fluid between the fibers and the brain tissue, are also made. Simulated I780 was 0.16 for gray matter, 0.67 for coagulate gray matter, 0.36 for thalamus, 0.39 for coagulated thalamus, unity for white matter, 0.70 for coagulated white matter, and 0.24 for blood. Thalamic matter is also found to reflect more light than gray matter and less than white matter in clinical studies. In conclusion, the reflected light intensity can be used to differentiate between gray and white matter during navigation. Furthermore, coagulation of light gray tissue, such as the thalamus, might be difficult to detect using I780, but coagulation in darker gray tissue should result in a rapid increase of I780.

  8. Transient analysis of the dynamic stress intensity factors using SGBEM for frequency-domain elastodynamics

    SciTech Connect

    Phan, Anh-Vu; Gray, Leonard J; Salvadori, Alberto

    2010-01-01

    In this paper, a two-dimensional symmetric-Galerkin boundary integral formulation for elastodynamic fracture analysis in the frequency domain is described. The numerical implementation is carried out with quadratic elements, allowing the use of an improved quarter-point element for accurately determining frequency responses of the dynamic stress intensity factors (DSIFs). To deal with singular and hypersingular integrals, the formulation is decomposed into two parts: the first part is identical to that for elastostatics while the second part contains at most logarithmic singularities. The treatment of the elastostatic singular and hypersingular singular integrals employs an exterior limit to the boundary, while the weakly singular integrals in the second part are handled by Gauss quadrature. Time histories (transient responses) of the DSIFs can be obtained in a post-processing step by applying the fast Fourier transform (FFT) and inverse FFT to the frequency responses of these DSIFs. Several test examples are presented for the calculation of the DSIFs due to two types of impact loading: Heaviside step loading and blast loading. The results suggest that the combination of symmetric-Galerkin and FFT algorithms in determining transient responses of the DSIFs is robust and effective.

  9. A regional GEV scale-invariant framework for Intensity-Duration-Frequency analysis

    NASA Astrophysics Data System (ADS)

    Blanchet, J.; Ceresetti, D.; Molinié, G.; Creutin, J.-D.

    2016-09-01

    We propose in this paper a regional formulation of Intensity-Duration-Frequency curves of point-rainfall maxima in a scale-invariant Generalized Extreme Value (GEV) framework. The two assumptions we make is that extreme daily rainfall is GEV-distributed - which is justified by Extreme Value Theory (EVT) - and that extremes of aggregated daily rainfall follow simple-scaling relationships. Following these assumptions, we develop in a unified way a GEV simple-scaling model for extremes of aggregated daily rainfall over the range of durations where scaling applies. Then we propose a way of correcting this model for measurement frequency, giving a new GEV-scaling model for extremes of aggregated hourly rainfall. This model deviates from the simple-scaling assumption. This framework is applied to the Mediterranean region of Cévennes-Vivarais, France. A network of about 300 daily raingage stations covering the last 50 years and accumulated to span the range 1 day-1 week is used to fit the scale invariant GEV-model locally. By means of spatial interpolation of the model parameters, and correction for measurement frequency, we are able to build a regional model with good performances down to 1 h duration, even though only one hourly station is used to build the model. Finally we produce mean and return level maps within the region in the range 1 h-1 week and comment on the potential rain storms leading to these maps.

  10. A frequency-based hypothesis for mechanically targeting and selectively attacking cancer cells

    PubMed Central

    Fraldi, M.; Cugno, A.; Deseri, L.; Dayal, K.; Pugno, N. M.

    2015-01-01

    Experimental studies recently performed on single cancer and healthy cells have demonstrated that the former are about 70% softer than the latter, regardless of the cell lines and the measurement technique used for determining the mechanical properties. At least in principle, the difference in cell stiffness might thus be exploited to create mechanical-based targeting strategies for discriminating neoplastic transformations within human cell populations and for designing innovative complementary tools to cell-specific molecular tumour markers, leading to possible applications in the diagnosis and treatment of cancer diseases. With the aim of characterizing and gaining insight into the overall frequency response of single-cell systems to mechanical stimuli (typically low-intensity therapeutic ultrasound), a generalized viscoelastic paradigm, combining classical and spring-pot-based models, is introduced for modelling this problem by neglecting the cascade of mechanobiological events involving the cell nucleus, cytoskeleton, elastic membrane and cytosol. Theoretical results show that differences in stiffness, experimentally observed ex vivo and in vitro, allow healthy and cancer cells to be discriminated, by highlighting frequencies (from tens to hundreds of kilohertz) associated with resonance-like phenomena—prevailing on thermal fluctuations—that could be helpful in targeting and selectively attacking tumour cells. PMID:26378121

  11. Changes in heat waves characteristics over Extremadura (SW Spain): duration, intensity and frequency

    NASA Astrophysics Data System (ADS)

    Acero, Javier; Parey, Sylvie; Fernández-Fernández, María Isabel; Carrasco, Víctor Manuel; Agustín García, José

    2016-04-01

    Heat waves (HW) are increasing and its consequences are important not only for the effects over the population but also for the agriculture and biodiversity. That's why trends in heat wave events over Extremadura, a Region located in the southwest of Spain and characterized by irrigated land with crops like corn or tomatoes growing in summers, has been studied. Heat waves are defined as days occurring above the 95th percentile of the summer (June-August) maximum temperature time series. Another event named as Warm Event (WE) has been studied and defined as exceedance over the 75th percentile. For this purpose, a set of 13 regularly distributed daily maximum temperature time series was selected from a larger database for the Region of Extremadura for the common period 1965-2014. A stochastic seasonal functional heteroscedastic auto-regressive model developed to simulate daily (minimum, maximum, or mean) temperature time series coherent with observed time series (Parey et al., 2014, Dacunha-Castelle et al., 2015) has been used. This stochastic temperature generator is used to reproduce 1000 time series equivalent to the observed ones in order to investigate the significance of the changes in HW characteristics: duration, intensity and frequency; using different sub-periods length for the observed period. The results show that the changes in HW frequencies of the last 10-year sub-period comparing to the first are significant for 7 of the 13 observatories but the changes in HW durations and intensities are not significant. But when considering the lower threshold (75th percentile) to study changes in WE characteristics, frequency shows significant changes in 8 observatories, duration for 4 observatories and intensity for 2. Then, the parameters of the WE are increasing higher than the corresponding to the HW events. References: Parey, S., T. T. H. Hoang, and D. Dacunha-Castelle (2014), Validation of a stochastic temperature generator focusing on extremes, and an

  12. Diffusion optical spectroscopy of cancerous and normal prostate tissues in time-resolved and frequency domain

    NASA Astrophysics Data System (ADS)

    Zhou, Kenneth J.; Pu, Yang; Chen, Jun

    2014-03-01

    It is well-known that light transport can be well described using Maxwell's electromagnetic theory. In biological tissue, the scattering particles cause the interaction of scattered waves from neighboring particles. Since such interaction cannot be ignored, multiple scattering occurs. The theoretical solution of multiple scattering is complicated. A suitable description is that the wavelike behavior of light is ignored and the transport of an individual photon is considered to be absorbed or scattered. This is known as the Radiative Transfer Equation (RTE) theory. Analytical solutions to the RTE that explicitly describes photon migration can be obtained by introducing some proper approximations. One of the most popular models used in the field of tissue optics is the Diffusion Approximation (DA). In this study, we report on the results of our initial study of optical properties of ex vivo normal and cancerous prostate tissues and how tissue parameters affect the near infrared light transporting in the two types of tissues. The time-resolved transport of light is simulated as an impulse isotropic point source of energy within a homogeneous unbounded medium with different absorption and scattering properties of cancerous and normal prostate tissues. Light source is also modulated sinusoidally to yield a varied fluence rate in frequency domain at a distant observation point within the cancerous and normal prostate tissues. Due to difference of the absorption and scattering coefficients between cancerous and normal tissues, the expansion of light pulse, intensity, phase are found to be different.

  13. High Intensity Focused Ultrasound for Cancer Therapy--harnessing its non-linearity

    SciTech Connect

    Haar, Gail ter

    2008-06-24

    In medicine in general, and for cancer treatments in particular, there is a drive to find effective non-invasive therapies. High Intensity Focused Ultrasound (HIFU) represents one such technique. In principle, it is simple--a high energy ultrasound beam is brought to a tight focus within a target which may lie several centimetres below the skin surface (for example, in a tumour of the liver), and is used to destroy a selected tissue volume. The main mechanism for cell killing in a HIFU beam is heat. Ultrasound energy absorption is frequency dependent, the higher frequencies being absorbed most strongly. Significant thermal advantage may therefore be gained from non-linear propagation, which generates higher harmonics, in tissue. Acoustic cavitation and thermal exsolution of gas (boiling) also contribute to tissue damage. This activity leads to the local mechanical disruption of cells. In addition, the non-linear oscillation of these bubbles leads to enhanced energy deposition. The acoustic emissions from such bubbles are characteristic of their behaviour and may be correlated to some extent with the appearance of the disruption produced. The more widespread clinical acceptance of HIFU is awaiting faster, and more efficient, energy delivery and treatment monitoring. A better understanding of the nonlinear aspects of HIFU propagation in tissue is thus important if this technique is to benefit more patients.

  14. Nonstationary Precipitation Intensity-Duration-Frequency Curves for Infrastructure Design in a Changing Climate

    PubMed Central

    Cheng, Linyin; AghaKouchak, Amir

    2014-01-01

    Extreme climatic events are growing more severe and frequent, calling into question how prepared our infrastructure is to deal with these changes. Current infrastructure design is primarily based on precipitation Intensity-Duration-Frequency (IDF) curves with the so-called stationary assumption, meaning extremes will not vary significantly over time. However, climate change is expected to alter climatic extremes, a concept termed nonstationarity. Here we show that given nonstationarity, current IDF curves can substantially underestimate precipitation extremes and thus, they may not be suitable for infrastructure design in a changing climate. We show that a stationary climate assumption may lead to underestimation of extreme precipitation by as much as 60%, which increases the flood risk and failure risk in infrastructure systems. We then present a generalized framework for estimating nonstationary IDF curves and their uncertainties using Bayesian inference. The methodology can potentially be integrated in future design concepts. PMID:25403227

  15. Measurement of spontaneity: the relationship between intensity and frequency of the spontaneous experience.

    PubMed

    Kipper, David A; Buras, Eva

    2009-04-01

    In the present article, the construct validity of one aspect of the definition of spontaneity is examined. Two ways of measuring spontaneity are presented. One involves the use of the revised version of a Spontaneity Assessment Inventory in which respondents are asked to indicate the intensity of the feeling of spontaneity they experience during a typical day. The second was a specially worded version of the Spontaneity Assessment Inventory-Revised: respondents were asked to indicate the frequency with which they experienced spontaneity during a typical day. 81 students responded to the two versions, which were given 1 wk. apart. The order of administration of the two versions was counterbalanced across the participants. The very high positive correlation between versions (r = .84) suggests that either measure may be used as an estimator of spontaneity.

  16. Prediction of Fundamental Vibrational Frequencies and Infrared Intensities: a Benchmark Study

    NASA Astrophysics Data System (ADS)

    Vázquez, Juana; Harding, Michael E.; Stanton, John F.

    2011-06-01

    In this work we investigate the performance of second-order vibrational perturbation theory (VPT2) using force fields computed at the fc-CCSD(T) level in conjunction with different double-, triple-, and quadruple-ζ basis sets for the prediction of fundamental vibrational frequencies and infrared intensities. A benchmark study comprising more than thirty small and medium sized molecules illustrates the accuracy and limitations of the presented scheme. Atomic natural orbital (ANOY, Y=0,1,2) [J. Almlöf and P. R. Taylor, J. Chem. Phys. 86, 4070 (1987)] and correlation-consistent (cc-pVXZ, X=D,T,Q) [T. H. Dunning, Jr., J. Chem. Phys. 90, 1007 (1989)] basis sets.

  17. Nonstationary precipitation Intensity-Duration-Frequency curves for infrastructure design in a changing climate.

    PubMed

    Cheng, Linyin; AghaKouchak, Amir

    2014-01-01

    Extreme climatic events are growing more severe and frequent, calling into question how prepared our infrastructure is to deal with these changes. Current infrastructure design is primarily based on precipitation Intensity-Duration-Frequency (IDF) curves with the so-called stationary assumption, meaning extremes will not vary significantly over time. However, climate change is expected to alter climatic extremes, a concept termed nonstationarity. Here we show that given nonstationarity, current IDF curves can substantially underestimate precipitation extremes and thus, they may not be suitable for infrastructure design in a changing climate. We show that a stationary climate assumption may lead to underestimation of extreme precipitation by as much as 60%, which increases the flood risk and failure risk in infrastructure systems. We then present a generalized framework for estimating nonstationary IDF curves and their uncertainties using Bayesian inference. The methodology can potentially be integrated in future design concepts. PMID:25403227

  18. Nonstationary Intensity-Duration-Frequency Curves for Drainge Infrastructure Coping with Climate Change

    NASA Astrophysics Data System (ADS)

    Kim, Byung Sik; Jeung, Se Jin; Lee, Dong Seop; Han, Woo Suk

    2015-04-01

    As the abnormal rainfall condition has been more and more frequently happen and serious by climate change and variabilities, the question whether the design of drainage system could be prepared with abnormal rainfall condition or not has been on the rise. Usually, the drainage system has been designed by rainfall I-D-F (Intensity-Duration-Frequency) curve with assumption that I-D-F curve is stationary. The design approach of the drainage system has limitation not to consider the extreme rainfall condition of which I-D-F curve is non-stationary by climate change and variabilities. Therefore, the assumption that the I-D-F curve is stationary to design drainage system maybe not available in the climate change period, because climate change has changed the characteristics of extremes rainfall event to be non-stationary. In this paper, design rainfall by rainfall duration and non-stationary I-D-F curve are derived by the conditional GEV distribution considering non-stationary of rainfall characteristics. Furthermore, the effect of designed peak flow with increase of rainfall intensity was analyzed by distributed rainfall-runoff model, S-RAT(Spatial Runoff Assessment Tool). Although there are some difference by rainfall duration, the traditional I-D-F curves underestimates the extreme rainfall events for high-frequency rainfall condition. As a result, this paper suggest that traditional I-D-F curves could not be suitable for the design of drainage system under climate change condition. Keywords : Drainage system, Climate Change, non-stationary, I-D-F curves This research was supported by a grant 'Development of multi-function debris flow control technique considering extreme rainfall event' [NEMA-Natural-2014-74] from the Natural Hazard Mitigation Research Group, National Emergency Management Agency of KOREA

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

    NASA Technical Reports Server (NTRS)

    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

  20. Modelling stock order flows with non-homogeneous intensities from high-frequency data

    NASA Astrophysics Data System (ADS)

    Gorshenin, Andrey K.; Korolev, Victor Yu.; Zeifman, Alexander I.; Shorgin, Sergey Ya.; Chertok, Andrey V.; Evstafyev, Artem I.; Korchagin, Alexander Yu.

    2013-10-01

    A micro-scale model is proposed for the evolution of such information system as the limit order book in financial markets. Within this model, the flows of orders (claims) are described by doubly stochastic Poisson processes taking account of the stochastic character of intensities of buy and sell orders that determine the price discovery mechanism. The proposed multiplicative model of stochastic intensities makes it possible to analyze the characteristics of the order flows as well as the instantaneous proportion of the forces of buyers and sellers, that is, the imbalance process, without modelling the external information background. The proposed model gives the opportunity to link the micro-scale (high-frequency) dynamics of the limit order book with the macro-scale models of stock price processes of the form of subordinated Wiener processes by means of limit theorems of probability theory and hence, to use the normal variance-mean mixture models of the corresponding heavy-tailed distributions. The approach can be useful in different areas with similar properties (e.g., in plasma physics).

  1. Intensity, duration, and frequency of precipitation extremes under 21st-century warming scenarios

    SciTech Connect

    Kao, Shih-Chieh; Ganguly, Auroop R

    2011-01-01

    Recent research on the projection of precipitation extremes has either focused on conceptual physical mechanisms that generate heavy precipitation or rigorous statistical methods that extrapolate tail behavior. However, informing both climate prediction and impact assessment requires concurrent physically and statistically oriented analysis. A combined examination of climate model simulations and observation-based reanalysis data sets suggests more intense and frequent precipitation extremes under 21st-century warming scenarios. Utilization of statistical extreme value theory and resampling-based uncertainty quantification combined with consideration of the Clausius-Clapeyron relationship reveals consistently intensifying trends for precipitation extremes at a global-average scale. However, regional and decadal analyses reveal specific discrepancies in the physical mechanisms governing precipitation extremes, as well as their statistical trends, especially in the tropics. The intensifying trend of precipitation extremes has quantifiable impacts on intensity-duration-frequency curves, which in turn have direct implications for hydraulic engineering design and water-resources management. The larger uncertainties at regional and decadal scales suggest the need for caution during regional-scale adaptation or preparedness decisions. Future research needs to explore the possibility of uncertainty reduction through higher resolution global climate models, statistical or dynamical downscaling, as well as improved understanding of precipitation extremes processes.

  2. Very low frequency radio events with a reduced intensity observed by the low-altitude DEMETER spacecraft

    NASA Astrophysics Data System (ADS)

    Záhlava, J.; Němec, F.; Santolík, O.; Kolmašová, I.; Parrot, M.; Rodger, C. J.

    2015-11-01

    We present results of a systematic study of unusual very low frequency (VLF) radio events with a reduced intensity observed in the frequency-time spectrograms measured by the low-orbiting Detection of Electro-Magnetic Emissions Transmitted from Earthquake Regions (DEMETER) spacecraft. They occur exclusively on the nightside. During these events, the intensity of fractional hop whistlers at specific frequencies is significantly reduced. These frequencies are usually above about 3.4 kHz (second Earth-ionosphere waveguide cutoff frequency), but about 20% of events extend down to about 1.7 kHz (first Earth-ionosphere waveguide cutoff frequency). The frequencies of a reduced intensity vary smoothly with time. We have inspected 6.5 years of DEMETER data, and we identified in total 1601 such events. We present a simple model of the event formation based on the wave propagation in the Earth-ionosphere waveguide. We apply the model to two selected events, and we demonstrate that the model is able to reproduce both the minimum frequencies of the events and their approximate frequency-time shapes. The overall geographic distribution of the events is shifted by about 3000 km westward and slightly southward with respect to the areas with high long-term average lightning activity. We demonstrate that this shift is related to the specific DEMETER orbit, and we suggest its qualitative explanation by the east-west asymmetry of the wave propagation in the Earth-ionosphere waveguide.

  3. Demeter/ICE Experiment: Study of low frequency transmitter intensity variations

    NASA Astrophysics Data System (ADS)

    Boudjada, M. Y.; Moldovan, I.; Schwingenschuh, K.; Al-Haddad, E.; Biagi, P. F.; Parrot, M.

    2012-04-01

    We report on low frequency (LF) transmitter signal recorded by the 'Instrument Capteur Electrique' (ICE) experiment onboard the DEMETER micro-satellite. We mainly consider the signal emitted by the Brasov broadcasting station (25.60E, 45.75N) at frequency of about 153 kHz. We analyze the reception conditions of this transmitter several weeks before the occurrence of the Vrancea earthquakes, on October, 27th, 2004. Ground-based observations revealed the presence of sudden decrease of the Y-component of the magnetic field at Muntele Rosu Observatory (Romania), at about 68 km from the epicenter, as reported by Moldovan et al. (Rom. Journ. Phys., Vol. 54, Nos. 1-2, p. 249-261, Bucharest, 2009). In this contribution we attempt to check if the LF Brasov signal was also subject to similar disturbances as observed by the ground-station. We focus on the variation of the LF transmitter intensity levels, several weeks before and after the Vrancea earthquake occurrence. We discuss the physical parameters which may disturb the signal reception in particular the geomagnetic activity and the signal to noise ratios.

  4. The molecular structure, vibrational force field, spectral frequencies, and infrared intensities of CH 3POF 2

    NASA Astrophysics Data System (ADS)

    von Carlowitz, Sunhild; Zeil, Werner; Pulay, Pðer; Boggs, James E.

    The molecular structure of CH 3POF 2 has been determined by MO-LCAO-SCF single determinant calculations using split valence shell basis sets with polarization functions on phosphorus. Interpretation of the results was aided by similar structural calculations on CH 3POH 2, CH 3PF 2, CH 3PH 2 and POF 3. In all cases, geometry optimization was performed by the gradient method using the TEXAS program. Comparison with experimental microwave results for CH 3POF 2 reveals an apparent error of interpretation in the experimental study leading to a radically incorrect angular distribution of bonds around the phosphorus atom. The vibrational force field of CH 3POF 2 has been determined by numerical differentiation of analytically determined energy gradients and used to compute the molecular vibrational spectrum and to provide approximate mode descriptions of the vibrational transitions. Agreement between the calculated and observed frequencies is reasonable and can be made very satisfactory by evaluation of a small number of scale factors to remove the systematic error common to vibrational frequencies calculated at this level of approximation. Dipole moment derivatives are also calculated and used to predict IR intensities.

  5. The effects of high-intensity, low-frequency active sonar on rainbow trout.

    PubMed

    Popper, Arthur N; Halvorsen, Michele B; Kane, Andrew; Miller, Diane L; Smith, Michael E; Song, Jiakun; Stein, Peter; Wysocki, Lidia E

    2007-07-01

    This study investigated the effects on rainbow trout (Oncorhynchus mykiss) of exposure to high-intensity, low-frequency sonar using an element of the standard Surveillance Towed Array Sensor System Low Frequency Active (LFA) sonar source array. Effects of the LFA sonar on hearing were tested using auditory brainstem responses. Effects were also examined on inner ear morphology using scanning electron microscopy and on nonauditory tissues using general pathology and histopathology. Animals were exposed to a maximum received rms sound pressure level of 193 dB re 1 microPa(2) for 324 or 648 s, an exposure that is far in excess of any exposure a fish would normally encounter in the wild. The most significant effect was a 20-dB auditory threshold shift at 400 Hz. However, the results varied with different groups of trout, suggesting developmental and/or genetic impacts on how sound exposure affects hearing. There was no fish mortality during or after exposure. Sensory tissue of the inner ears did not show morphological damage even several days post-sound exposure. Similarly, gross- and histopathology observations demonstrated no effects on nonauditory tissues.

  6. Broad-bandwidth near-shot-noise-limited intensity noise suppression of a single-frequency fiber laser.

    PubMed

    Zhao, Qilai; Xu, Shanhui; Zhou, Kaijun; Yang, Changsheng; Li, Can; Feng, Zhouming; Peng, Mingying; Deng, Huaqiu; Yang, Zhongmin

    2016-04-01

    A significant broad-bandwidth near-shot-noise-limited intensity noise suppression of a single-frequency fiber laser is demonstrated based on a semiconductor optical amplifier (SOA) with optoelectronic feedback. By exploiting the gain saturation effect of the SOA and the intensity feedback loop, a maximum noise suppression of over 50 dB around the relaxation oscillation frequencies and a suppression bandwidth of up to 50 MHz are obtained. The relative intensity noise of -150  dB/Hz in the frequency range from 0.8 kHz to 50 MHz is achieved, which approaches the shot-noise limit. The obtained optical signal-to-noise ratio is more than 70 dB. This near-shot-noise-limited laser source shows important implications for the advanced fields of high-precision frequency stabilization, quantum key distribution, and gravitational wave detection. PMID:27192229

  7. Frequency of hospital acquired pneumonia and its microbiological etiology in medical intensive care unit

    PubMed Central

    Imran, Muhammad; Amjad, Alina; Haidri, Fakhir Raza

    2016-01-01

    Objective: The objectives were to assess the frequency of hospital acquired pneumonia (HAP) in patients admitted to intensive care unit (ICU) and to determine the frequencies of different etiological organisms in these patients. Methods: This was descriptive cross sectional study, which was carried out in medical ICU of Shifa International Hospital Islamabad from January 2013 to January 2014. A total of 1866 patients were admitted in the department of medicine including medical ICU. They were evaluated for HAP and the causative organisms were cultured from these patients. Identification was carried out by standard biochemical profile of the organisms. Results: The total number of patients admitted in medical ICU for any reason were 346. HAP was diagnosed in 88 patients (25.4%). The average age of patients admitted in Medical ICU with HAP was 48 years with the range of 16 to 82 years. 56 were male and 32 females. 42 patients (47.7%) died in medical ICU with HAP. Microbiological analysis showed that Pseudomonas aeruginosa were 27 (30.6%), Acinetobacter spp. were 12 (13.6%), Candida albicans were 12 (13.6%), Klebsiellapneumoniae were 9 (10.2%), Streptococcus spp. were 9 (10.2%), Escherichia coli were 5 (5.6%), Stenotrophomonas spp. were 4(4.5%), Methicillin Resistant Staphylococcus Aureus (MRSA) were 4 (4.5%) others organisms 6 (6.8%). Conclusion: The frequency of HAP in Medical ICU of our hospital is 88 out of 346 (25.4%). The commonest organism identified was Pseudomonas aeruginosa (30.6%) followed by Acinetobacter and Candida albican (13.6% each).

  8. Frequency of hospital acquired pneumonia and its microbiological etiology in medical intensive care unit

    PubMed Central

    Imran, Muhammad; Amjad, Alina; Haidri, Fakhir Raza

    2016-01-01

    Objective: The objectives were to assess the frequency of hospital acquired pneumonia (HAP) in patients admitted to intensive care unit (ICU) and to determine the frequencies of different etiological organisms in these patients. Methods: This was descriptive cross sectional study, which was carried out in medical ICU of Shifa International Hospital Islamabad from January 2013 to January 2014. A total of 1866 patients were admitted in the department of medicine including medical ICU. They were evaluated for HAP and the causative organisms were cultured from these patients. Identification was carried out by standard biochemical profile of the organisms. Results: The total number of patients admitted in medical ICU for any reason were 346. HAP was diagnosed in 88 patients (25.4%). The average age of patients admitted in Medical ICU with HAP was 48 years with the range of 16 to 82 years. 56 were male and 32 females. 42 patients (47.7%) died in medical ICU with HAP. Microbiological analysis showed that Pseudomonas aeruginosa were 27 (30.6%), Acinetobacter spp. were 12 (13.6%), Candida albicans were 12 (13.6%), Klebsiellapneumoniae were 9 (10.2%), Streptococcus spp. were 9 (10.2%), Escherichia coli were 5 (5.6%), Stenotrophomonas spp. were 4(4.5%), Methicillin Resistant Staphylococcus Aureus (MRSA) were 4 (4.5%) others organisms 6 (6.8%). Conclusion: The frequency of HAP in Medical ICU of our hospital is 88 out of 346 (25.4%). The commonest organism identified was Pseudomonas aeruginosa (30.6%) followed by Acinetobacter and Candida albican (13.6% each). PMID:27648021

  9. [The patient with lung cancer in intensive care].

    PubMed

    Meert, A-P; Berghmans, T; Sculier, J-P

    2014-12-01

    In Western countries, lung cancer (LC) is the most common cause of cancer death. It is present in 15-20% of patients admitted to the ICU with a neoplastic condition. The purpose of this article is to review the causes of admission to ICU of patients with LC, their prognosis and the results of different life-support techniques. Most studies include mixed populations of non-small cell (NSCLC) and small-cell lung cancers (SCLC). However, there is preponderance of NSCLC (70%) and LC of advanced or metastatic stages, reflecting the distribution in the general population of LC. The cause of admission of LC patients to ICU is most often of respiratory origin. The ICU mortality rate currently ranges from 13 to 47% and the hospital mortality rate from 24 to 65%. The predictors of in-hospital mortality are mainly severity scores, organ dysfunction, general condition (performance status), respiratory distress and the need for mechanical ventilation or vasopressor drugs. When considering the long-term mortality, it is the features of the cancer (presence of metastases, cancer progression) that are important predictive factors.

  10. Is the interannual variability of summer rainfall in China dominated by precipitation frequency or intensity? An analysis of relative importance

    NASA Astrophysics Data System (ADS)

    Lu, Er; Ding, Ying; Zhou, Bing; Zou, Xukai; Chen, Xianyan; Cai, Wenyue; Zhang, Qiang; Chen, Haishan

    2016-07-01

    The summer rainfall in China has a large interannual variability, which results from the concurrent variations of precipitation frequency and intensity. Using the observed daily precipitation in the 194 stations during recent 62 years, we examine the relative importance of the frequency and intensity in the variability of the rainfall. A simple method, based on linear regression, is used to estimate the relative importance. The products of the change rates of rainfall with respect to frequency and intensity, determined from the regression, and the corresponding standard deviations of the two variables, which reflect their variation scales, are defined to measure the importance of frequency and intensity. To determine the frequency, rainfall amount, and intensity from daily precipitation, we need a threshold to define the "rainy day". In this study, we use a series of thresholds, ranging from 1 to 30 mm/day. So, while presenting the result of relative importance for each threshold, we also examine how the relative importance varies with the threshold. Results show that for the threshold of 1 mm/day, with which the rainfall may include even the light rains, the variabilities of summer rainfall in most stations are dominated by intensity. With the increase in threshold, the importance of frequency increases, while the importance of intensity decreases. When the threshold reaches 30 mm/day, with which the rainfall includes only moderate-to-heavy rains, the variabilities of the rainfall in all stations are dominated by frequency. Analysis suggests that such a change, in the dominance with the threshold, is reasonable. This reasonability, in turn, supports the reliability and robustness of the method.

  11. Splitting intensity measurements of North America and finite-frequency modeling of upper mantle anisotropy

    NASA Astrophysics Data System (ADS)

    Hongsresawat, Sutatcha

    micro terranes with both continental and oceanic origins throughout its accretion history making it a very complex geological setting including the presence of the north-striking western Idaho shear zone (WISZ) in the middle. We deployed 85 temporary seismic stations with station-spacing of ˜30 km during 2011--2013 and passively recorded seismic data for an average duration of 1.5 years. The SKS phase of the seismogram is used to obtain splitting intensity, which we use to model realistic 3-D upper-mantle anisotropy. There are two parts in this study, first SKS splitting intensity measurements were made from seismograms recorded at 83 IDOR seismic stations and 45 USArray-TA stations, which consist of analyzing more than 75,000 individual traces. As a result, we obtain high-resolution and spatially coherent shear-wave splitting dataset of the IDOR region. Second, we use back-azimuthal variations of splitting intensity at all stations to model for 3-D anisotropy using the finite-frequency approach. Preliminary models show depth-dependent behaviors of both fast polarization direction and strength of anisotropy down to ˜150 km where the model starts to show poor resolution due to the size of the SKS fresnel zone. Last, we show preliminary inverted models for 3-D upper-mantle anisotropy of North America as well as our progress of spherical coordinate inversion of the USArray-TA splitting measurements. This will set up a starting point for performing a joint-inversion with surface wave dataset that will be measured at exact seismic stations. This last task will be exercised by the help of 3-D finite-frequency Frechet sensitivity kernels for surface waveforms based on the Born approximation with a model parametrized for hexagonal symmetry. Their formulation will provide a complementary approach to invert surface wave data in combination with our SI data for upper mantle anisotropy model of North America with highest resolution for the first time.

  12. Neurons in the inferior colliculus of the rat show stimulus-specific adaptation for frequency, but not for intensity.

    PubMed

    Duque, Daniel; Wang, Xin; Nieto-Diego, Javier; Krumbholz, Katrin; Malmierca, Manuel S

    2016-04-12

    Electrophysiological and psychophysical responses to a low-intensity probe sound tend to be suppressed by a preceding high-intensity adaptor sound. Nevertheless, rare low-intensity deviant sounds presented among frequent high-intensity standard sounds in an intensity oddball paradigm can elicit an electroencephalographic mismatch negativity (MMN) response. This has been taken to suggest that the MMN is a correlate of true change or "deviance" detection. A key question is where in the ascending auditory pathway true deviance sensitivity first emerges. Here, we addressed this question by measuring low-intensity deviant responses from single units in the inferior colliculus (IC) of anesthetized rats. If the IC exhibits true deviance sensitivity to intensity, IC neurons should show enhanced responses to low-intensity deviant sounds presented among high-intensity standards. Contrary to this prediction, deviant responses were only enhanced when the standards and deviants differed in frequency. The results could be explained with a model assuming that IC neurons integrate over multiple frequency-tuned channels and that adaptation occurs within each channel independently. We used an adaptation paradigm with multiple repeated adaptors to measure the tuning widths of these adaption channels in relation to the neurons' overall tuning widths.

  13. Neurons in the inferior colliculus of the rat show stimulus-specific adaptation for frequency, but not for intensity

    PubMed Central

    Duque, Daniel; Wang, Xin; Nieto-Diego, Javier; Krumbholz, Katrin; Malmierca, Manuel S.

    2016-01-01

    Electrophysiological and psychophysical responses to a low-intensity probe sound tend to be suppressed by a preceding high-intensity adaptor sound. Nevertheless, rare low-intensity deviant sounds presented among frequent high-intensity standard sounds in an intensity oddball paradigm can elicit an electroencephalographic mismatch negativity (MMN) response. This has been taken to suggest that the MMN is a correlate of true change or “deviance” detection. A key question is where in the ascending auditory pathway true deviance sensitivity first emerges. Here, we addressed this question by measuring low-intensity deviant responses from single units in the inferior colliculus (IC) of anesthetized rats. If the IC exhibits true deviance sensitivity to intensity, IC neurons should show enhanced responses to low-intensity deviant sounds presented among high-intensity standards. Contrary to this prediction, deviant responses were only enhanced when the standards and deviants differed in frequency. The results could be explained with a model assuming that IC neurons integrate over multiple frequency-tuned channels and that adaptation occurs within each channel independently. We used an adaptation paradigm with multiple repeated adaptors to measure the tuning widths of these adaption channels in relation to the neurons’ overall tuning widths. PMID:27066835

  14. Radio frequency radiation-induced hyperthermia using Si nanoparticle-based sensitizers for mild cancer therapy.

    PubMed

    Tamarov, Konstantin P; Osminkina, Liubov A; Zinovyev, Sergey V; Maximova, Ksenia A; Kargina, Julia V; Gongalsky, Maxim B; Ryabchikov, Yury; Al-Kattan, Ahmed; Sviridov, Andrey P; Sentis, Marc; Ivanov, Andrey V; Nikiforov, Vladimir N; Kabashin, Andrei V; Timoshenko, Victor Yu

    2014-01-01

    Offering mild, non-invasive and deep cancer therapy modality, radio frequency (RF) radiation-induced hyperthermia lacks for efficient biodegradable RF sensitizers to selectively target cancer cells and thus avoid side effects. Here, we assess crystalline silicon (Si) based nanomaterials as sensitizers for the RF-induced therapy. Using nanoparticles produced by mechanical grinding of porous silicon and ultraclean laser-ablative synthesis, we report efficient RF-induced heating of aqueous suspensions of the nanoparticles to temperatures above 45-50 °C under relatively low nanoparticle concentrations (<1 mg/mL) and RF radiation intensities (1-5 W/cm(2)). For both types of nanoparticles the heating rate was linearly dependent on nanoparticle concentration, while laser-ablated nanoparticles demonstrated a remarkably higher heating rate than porous silicon-based ones for the whole range of the used concentrations from 0.01 to 0.4 mg/mL. The observed effect is explained by the Joule heating due to the generation of electrical currents at the nanoparticle/water interface. Profiting from the nanoparticle-based hyperthermia, we demonstrate an efficient treatment of Lewis lung carcinoma in vivo. Combined with the possibility of involvement of parallel imaging and treatment channels based on unique optical properties of Si-based nanomaterials, the proposed method promises a new landmark in the development of new modalities for mild cancer therapy. PMID:25391603

  15. Radio frequency radiation-induced hyperthermia using Si nanoparticle-based sensitizers for mild cancer therapy.

    PubMed

    Tamarov, Konstantin P; Osminkina, Liubov A; Zinovyev, Sergey V; Maximova, Ksenia A; Kargina, Julia V; Gongalsky, Maxim B; Ryabchikov, Yury; Al-Kattan, Ahmed; Sviridov, Andrey P; Sentis, Marc; Ivanov, Andrey V; Nikiforov, Vladimir N; Kabashin, Andrei V; Timoshenko, Victor Yu

    2014-11-13

    Offering mild, non-invasive and deep cancer therapy modality, radio frequency (RF) radiation-induced hyperthermia lacks for efficient biodegradable RF sensitizers to selectively target cancer cells and thus avoid side effects. Here, we assess crystalline silicon (Si) based nanomaterials as sensitizers for the RF-induced therapy. Using nanoparticles produced by mechanical grinding of porous silicon and ultraclean laser-ablative synthesis, we report efficient RF-induced heating of aqueous suspensions of the nanoparticles to temperatures above 45-50 °C under relatively low nanoparticle concentrations (<1 mg/mL) and RF radiation intensities (1-5 W/cm(2)). For both types of nanoparticles the heating rate was linearly dependent on nanoparticle concentration, while laser-ablated nanoparticles demonstrated a remarkably higher heating rate than porous silicon-based ones for the whole range of the used concentrations from 0.01 to 0.4 mg/mL. The observed effect is explained by the Joule heating due to the generation of electrical currents at the nanoparticle/water interface. Profiting from the nanoparticle-based hyperthermia, we demonstrate an efficient treatment of Lewis lung carcinoma in vivo. Combined with the possibility of involvement of parallel imaging and treatment channels based on unique optical properties of Si-based nanomaterials, the proposed method promises a new landmark in the development of new modalities for mild cancer therapy.

  16. Radio frequency radiation-induced hyperthermia using Si nanoparticle-based sensitizers for mild cancer therapy

    NASA Astrophysics Data System (ADS)

    Tamarov, Konstantin P.; Osminkina, Liubov A.; Zinovyev, Sergey V.; Maximova, Ksenia A.; Kargina, Julia V.; Gongalsky, Maxim B.; Ryabchikov, Yury; Al-Kattan, Ahmed; Sviridov, Andrey P.; Sentis, Marc; Ivanov, Andrey V.; Nikiforov, Vladimir N.; Kabashin, Andrei V.; Timoshenko, Victor Yu

    2014-11-01

    Offering mild, non-invasive and deep cancer therapy modality, radio frequency (RF) radiation-induced hyperthermia lacks for efficient biodegradable RF sensitizers to selectively target cancer cells and thus avoid side effects. Here, we assess crystalline silicon (Si) based nanomaterials as sensitizers for the RF-induced therapy. Using nanoparticles produced by mechanical grinding of porous silicon and ultraclean laser-ablative synthesis, we report efficient RF-induced heating of aqueous suspensions of the nanoparticles to temperatures above 45-50°C under relatively low nanoparticle concentrations (<1 mg/mL) and RF radiation intensities (1-5 W/cm2). For both types of nanoparticles the heating rate was linearly dependent on nanoparticle concentration, while laser-ablated nanoparticles demonstrated a remarkably higher heating rate than porous silicon-based ones for the whole range of the used concentrations from 0.01 to 0.4 mg/mL. The observed effect is explained by the Joule heating due to the generation of electrical currents at the nanoparticle/water interface. Profiting from the nanoparticle-based hyperthermia, we demonstrate an efficient treatment of Lewis lung carcinoma in vivo. Combined with the possibility of involvement of parallel imaging and treatment channels based on unique optical properties of Si-based nanomaterials, the proposed method promises a new landmark in the development of new modalities for mild cancer therapy.

  17. Frequency analysis of ultrasonic echo intensities of the skeletal muscle in elderly and young individuals

    PubMed Central

    Nishihara, Ken; Kawai, Hisashi; Hayashi, Hiroyuki; Naruse, Hideo; Kimura, Akihiko; Gomi, Toshiaki; Hoshi, Fumihiko

    2014-01-01

    Background The skeletal muscle echo intensity (EI) during ultrasound imaging has been investigated to evaluate the muscle quality. However, EI fluctuates according to the scanning conditions. Methods The motor functions and ultrasound images of 19 elderly (73±3.2 years) and 19 young (22±1.5 years) individuals were investigated and an EI frequency component was assessed for more reliable evaluations. Healthy elderly and young subjects participated in this study. The motor functions were assessed during walking and according to the knee extension muscle strength. The muscle thicknesses of rectus femoris (RF), vastus intermedius (VI), and quadriceps femoris (QF) were investigated. EIs were calculated and the mean frequencies of the regions of interest (MFROIs) for RF and VI were analyzed. Results EIs and MFROIs were greater in elderly subjects than in young subjects (P<0.01 for RF, and P<0.001 for VI, in EIs; and P<0.01 for RF, and P<0.05 for VI, in MFROIs). In young subjects, EI of RF was greater than that of VI; however, there was no difference between the RF and VI MFROIs in both elderly and young subjects. EIs of VI exhibited a significantly negative correlation with the QF thickness in both elderly and young subjects. RF MFROIs negatively correlated with the QF thickness and positively correlated with EI of VI in elderly subjects alone. Conclusion These findings suggest that MFROIs of elderly individuals would have a larger value than those of young individuals; moreover, MFROIs did not fluctuate greatly with the tissue depth and scanning conditions. MFROIs might be thus useful for further investigations of muscle quality and applications for the early prevention of age-related motor functional decline. PMID:25228800

  18. Radio frequency needle hyperthermia of normal and cancerous animal tissue

    NASA Astrophysics Data System (ADS)

    Shalhav, Arieh; Ramon, J.; Goldwasser, Benad; Nativ, Ofer; Cherniack, Ramy; Zajdel, Liliana

    1994-12-01

    Capacitative radio frequency (RF) was met with little success when used to treat human cancer. Conductive rf needle hyperthermia (RFNH) is used successfully for human tissue ablation in neurosurgery, cardiology, and recently in urology. RFNH ablates tissue by causing thermal damage limited to the vicinity of the rf needle. We conducted a series of studies to evaluate the effect of RFNH on cancerous and normal tissue. RFNH was applied to normal porcine livers during open surgery. Liver function tests were elevated two days post treatment, then returned to normal. Pigs were sequentially sacrificed. RFNH induced lesions were found to be maximal in size on days 2 - 4 post treatment and later became smaller as liver regenerated. Phase 2 included mice bearing two subcutaneous murine bladder tumors (MBT2). The rf needle was inserted into both tumors of each mouse, but rf current was applied to one tumor only. Energies of 3 to 7.5 watts were applied for 30 seconds to 5 minutes using a 0.02 inch needle. Mice were sacrificed 0, 1, and 3 days after treatment. Necrotic lesions 0.5 - 1.2 cm in diameter were found within the treated tumors. In phase 3, mice bearing a single 8 - 18 mm subcutaneous tumor were treated by RFNH aiming for complete tumor destruction. All control mice died of huge tumors within 31 days. Treated mice were alive with no signs of tumor when sacrificed 60 days after treatment. In phase 3 RFNH is capable of complete tumor eradication with little damage to surrounding normal tissue. It may have clinical applications for percutaneous endoscopic and laparoscopic treatment of tumors.

  19. Suppression of the low frequency intensity noise of a single-frequency Yb3+-doped phosphate fiber laser at 1083 nm

    NASA Astrophysics Data System (ADS)

    Feng, Z.; Li, C.; Xu, S.; Yang, C.; Mo, S.; Chen, D.; Peng, M.; Yang, Z.

    2014-06-01

    The suppression of the low frequency intensity noise of a 1083 nm single-frequency Yb3+-doped phosphate fiber laser is reported. The noise suppression scheme is to use a liquid crystal device as a variable attenuator to modulate the laser power to close to the desired level. The achieved long term (12 h) laser instability is less than 0.2%, while the relative intensity noise (RIN) has been decreased to lower than -140 dB Hz-1 at frequencies from 250 Hz to 1 kHz. Moreover, the laser linewidth value remains the same as before suppression, while the degree of polarization (DOP) declined slightly.

  20. Neutron intensity modulation and time-focusing with integrated Larmor and resonant frequency techniques

    SciTech Connect

    Zhao, Jinkui Hamilton, William A.; Robertson, J. L.; Crow, Lowell; Lee, Sung-Woo; Kang, Yoon W.

    2015-09-14

    The analysis of neutron diffraction experiments often assumes that neutrons are elastically scattered from the sample. However, there is growing evidence that a significant fraction of the detected neutrons is in fact inelastically scattered, especially from soft materials and aqueous samples. Ignoring these inelastic contributions gives rise to inaccurate experimental results. To date, there has been no simple method with broad applicability for inelastic signal separation in neutron diffraction experiments. Here, we present a simple and robust method that we believe could be suited for this purpose. We use two radio frequency resonant spin flippers integrated with a Larmor precession field to modulate the neutron intensity and to encode the inelastic scattering information into the neutron data. All three components contribute to the spin encoding. The Larmor field serves several additional purposes. Its usage facilitates neutron time-focusing, eliminates the need for stringent magnetic shielding, and allows for compact setups. The scheme is robust, simple, and flexible. We believe that, with further improvements, it has the potential of adding inelastic signal discrimination capabilities to many existing diffraction instruments in the future.

  1. Frequency and intensity of exposure mediate resistance to experimental infection with the hookworm, Ancylostoma ceylanicum

    PubMed Central

    Davey, Dylan; Manickam, Nisha; Simms, Benjamin T.; Harrison, Lisa M.; Vermeire, Jon J.; Cappello, Michael

    2013-01-01

    Hookworms are bloodfeeding intestinal nematodes that are a major cause of anemia in resource-limited countries. Despite repeated exposure beginning in early childhood, humans retain lifelong susceptibility to infection without evidence of sterilizing immunity. In contrast, experimental infection of laboratory animals is typically characterized by varying degrees of resistance following primary infection, although the mechanisms underlying this phenomenon remain unknown. In this study, hamsters subjected to a single drug-terminated infection with 100 third stage hookworm larvae were confirmed to be resistant to pathological effects following a subsequent challenge. In a second experiment, hamsters infected twice-weekly with 10 third stage larvae (low inoculum) exhibited clinical and parasitological evidence of continued susceptibility, while those given 100 L3 (high inoculum) developed apparent resistance within 3 days following the initial exposure. The kinetics of parasite-specific IgA, IgM, and IgG antibody production varied by group, which suggests that the humoral immune response to hookworm infection is stimulated by the nature (frequency and intensity) of larval exposure. These results suggest that intermittent low-inoculum larval exposure, which is characterized by prolonged susceptibility to infection, may serve as a more representative model of human hookworm disease for studies of pathogenesis, as well as drug and vaccine development. PMID:23232252

  2. Neutron intensity modulation and time-focusing with integrated Larmor and resonant frequency techniques

    NASA Astrophysics Data System (ADS)

    Zhao, Jinkui; Hamilton, William A.; Lee, Sung-Woo; Robertson, J. L.; Crow, Lowell; Kang, Yoon W.

    2015-09-01

    The analysis of neutron diffraction experiments often assumes that neutrons are elastically scattered from the sample. However, there is growing evidence that a significant fraction of the detected neutrons is in fact inelastically scattered, especially from soft materials and aqueous samples. Ignoring these inelastic contributions gives rise to inaccurate experimental results. To date, there has been no simple method with broad applicability for inelastic signal separation in neutron diffraction experiments. Here, we present a simple and robust method that we believe could be suited for this purpose. We use two radio frequency resonant spin flippers integrated with a Larmor precession field to modulate the neutron intensity and to encode the inelastic scattering information into the neutron data. All three components contribute to the spin encoding. The Larmor field serves several additional purposes. Its usage facilitates neutron time-focusing, eliminates the need for stringent magnetic shielding, and allows for compact setups. The scheme is robust, simple, and flexible. We believe that, with further improvements, it has the potential of adding inelastic signal discrimination capabilities to many existing diffraction instruments in the future.

  3. High-frequency, correlated nuclear and electron oscillations in molecules in intense laser fields

    NASA Astrophysics Data System (ADS)

    Bandrauk, André D.; Chelkowski, Szczepan; Lu, Huizhong

    2013-03-01

    We have solved numerically the time-dependent Schrödinger equation (TDSE) describing dissociative-ionization of a H2 (and of a D2) molecule exposed to intense short-pulse laser light in one dimension. From the time dependent wave function we calculated the total average acceleration of the two electrons and the relative proton acceleration and the average of internuclear distance. We find that the general shape of the power spectra of electron and proton motion is very similar except that for the electrons the peaks occur at odd harmonics whereas for protons the peaks occur at even harmonics. We relate this to the appearance of higher order polarizabilities. The wavelet time-frequency analysis shows that, surprisingly, time profiles of electron and proton accelerations are nearly identical for high order harmonics. The wavelet time profiles confirm predictions of the three-step quasi-classical model of harmonic generation by identifying several (up to three) electron return times with high precision.

  4. Prototype fiber Bragg Grattings (FBG) sensor based on intensity modulation of the laser diode low frequency vibrations measurement

    NASA Astrophysics Data System (ADS)

    Setiono, Andi; Ula, Rini Khamimatul; Hanto, Dwi; Widiyatmoko, Bambang; Purnamaningsih, Retno Wigajatri

    2016-02-01

    In general, Fiber Bragg Grating (FBG) sensor works based on observation of spectral response characteristic to detect the desired parameter. In this research, we studied intensity response characteristic of FBG to detect the dynamic strain. Experiment result show that the reflected intensity had linier relationships with dynamic strain. Based on these characteristics, we developed the FBG sensor to detect low frequency vibration. This sensor is designed by attaching the FBG on the bronze cantilever with dimensions of 85×3×0.5 mm. Measurement results showed that the sensor was able to detect vibrations in the frequency range of 7-10 Hz at temperature range of 25-45 ˚C. The measured frequency range is still within the frequency range of digging activity, therefore this vibration sensor can be applied for oil pipelines vandalisation detection system.

  5. Ovarian blood flow responses to electro-acupuncture stimulation at different frequencies and intensities in anaesthetized rats.

    PubMed

    Stener-Victorin, Elisabet; Kobayashi, Rie; Kurosawa, Mieko

    2003-10-31

    The purpose of the present study was to investigate changes in ovarian blood flow (OBF) in response to electro-acupuncture (EA) stimulation at different frequencies and intensities in anaesthetized rats. Whether the ovarian sympathetic nerves were involved in OBF responses was elucidated by severance of the ovarian sympathetic nerves. In addition, how changes in the systemic circulation affected OBF was evaluated by continuously recording blood pressure. OBF was measured on the surface of the left ovary using laser Doppler flowmeter. Acupuncture needles with a diameter of 0.3 mm were inserted bilaterally into the abdominal and the hindlimb muscles and connected to an electrical stimulator. Two frequencies-2 Hz (low) and 80 Hz (high)-with three different intensities-1.5, 3, and 6 mA-were applied for 35 s. Both low- and high-frequency EA at 1.5 mA and high-frequency EA at 3 mA had no effect on OBF or mean arterial blood pressure (MAP). Low-frequency EA at 3 and 6 mA elicited significant increases in OBF. In contrast, high-frequency EA with an intensity of 6 mA evoked significant decreases in OBF, followed by decreases in MAP. After severance of the ovarian sympathetic nerves, the increases in the OBF responses to low-frequency EA at 3 and 6 mA were totally abolished, and the responses at 6 mA showed a tendency to decrease, probably because of concomitant decreases in MAP. The decreased OBF and MAP responses to high-frequency EA at 6 mA remained after the ovarian sympathectomy, and the difference in the responses before and after ovarian sympathectomy was nonsignificant. In conclusion, the present study showed that low-frequency EA stimulation increases OBF as a reflex response via the ovarian sympathetic nerves, whereas high-frequency EA stimulation decreases OBF as a passive response following systemic circulatory changes.

  6. Intensity noise in diode-pumped single-frequency Nd:YAG lasers and its control by electronic feedback

    NASA Technical Reports Server (NTRS)

    Kane, Thomas J.

    1990-01-01

    The power spectrum of the relative intensity noise (RIN) of single-frequency diode-pumped Nd:YAG lasers is observed to be shot-noise limited at frequencies above 20 MHz for a photocurrent of up to 4.4 mA. Relaxation oscillations result in noise 60-70 dB above shot noise at a few hundred kHz. These relaxation oscillations have been suppressed using electronic feedback.

  7. Effect of Air-Sea coupling on the Frequency Distribution of Intense Tropical Cyclones over the Northwestern Pacific

    NASA Astrophysics Data System (ADS)

    Ogata, Tomomichi; Mizuta, Ryo; Adachi, Yukimasa; Murakami, Hiroyuki; Ose, Tomomaki

    2016-04-01

    Effect of air-sea coupling on the frequency distribution of intense tropical cyclones (TCs) over the northwestern Pacific (NWP) region is investigated using an atmosphere and ocean coupled general circulation model (AOGCM). Monthly varying flux adjustment enables AOGCM to simulate both subseasonal air-sea interaction and realistic seasonal to interannual SST variability. The maximum of intense TC distribution around 20-30°N in the AGCM shifts equatorward in the AOGCM due to the air-sea coupling. Hence AOGCM reduces northward intense TC distribution bias seen in AGCM. Over the NWP, AOGCM-simulated SST variability is large around 20-30°N where the warm mixed layer becomes shallower rapidly. Active entrainment from subsurface water over this region causes stronger SST cooling and hence TC intensity decreases. These results suggest that air-sea coupling characterized by subsurface oceanic condition causes more realistic distribution of intense TCs over the NWP.

  8. Effect of air-sea coupling on the frequency distribution of intense tropical cyclones over the northwestern Pacific

    NASA Astrophysics Data System (ADS)

    Ogata, Tomomichi; Mizuta, Ryo; Adachi, Yukimasa; Murakami, Hiroyuki; Ose, Tomoaki

    2015-12-01

    Effect of air-sea coupling on the frequency distribution of intense tropical cyclones (TCs) over the northwestern Pacific (NWP) region is investigated using an atmosphere and ocean coupled general circulation model (AOGCM). Monthly varying flux adjustment enables AOGCM to simulate both subseasonal air-sea interaction and realistic seasonal to interannual sea surface temperature (SST) variability. The maximum of intense TC distribution around 20-30°N in the AGCM shifts equatorward in the AOGCM due to the air-sea coupling. Hence, AOGCM reduces northward intense TC distribution bias seen in AGCM. Over the NWP, AOGCM-simulated SST variability is large around 20-30°N where the warm mixed layer becomes shallower rapidly. Active entrainment from subsurface water over this region causes stronger SST cooling, and hence, TC intensity decreases. These results suggest that air-sea coupling characterized by subsurface oceanic condition causes more realistic distribution of intense TCs over the NWP.

  9. The radiation techniques of tomotherapy & intensity-modulated radiation therapy applied to lung cancer

    PubMed Central

    Zhu, Zhengfei

    2015-01-01

    Radiotherapy (RT) plays an important role in the management of lung cancer. Development of radiation techniques is a possible way to improve the effect of RT by reducing toxicities through better sparing the surrounding normal tissues. This article will review the application of two forms of intensity-modulated radiation therapy (IMRT), fixed-field IMRT and helical tomotherapy (HT) in lung cancer, including dosimetric and clinical studies. The advantages and potential disadvantages of these two techniques are also discussed. PMID:26207214

  10. Transrectal high-intensity focused ultrasound for the treatment of prostate cancer: Past, present, and future

    PubMed Central

    Mearini, Luigi; Porena, Massimo

    2010-01-01

    Upon a review of recently published articles on high-intensity focused ultrasound (HIFU) in the treatment of prostate cancer, we evaluated the current status of HIFU as a primary treatment option for localized prostate cancer and its use as salvage therapy when radiation failed. We also briefly discuss current issues in indications, definition of response, and finally the future of HIFU development. PMID:20535278

  11. Increased risk of cancer in radon-exposed miners with elevated frequency of chromosomal aberrations.

    PubMed

    Smerhovsky, Zdenek; Landa, Karel; Rössner, Pavel; Juzova, Dagmar; Brabec, Marek; Zudova, Zdena; Hola, Nora; Zarska, Hana; Nevsimalova, Emilie

    2002-02-15

    In spite of the extensive use of cytogenetic analysis of human peripheral blood lymphocytes in the biomonitoring of exposure to various mutagens and carcinogens, the long-term effects of an increased frequency of chromosomal aberrations in individuals are still uncertain. Few epidemiologic studies have addressed this issue, and a moderate risk of cancer in individuals with an elevated frequency of chromosomal aberrations has been observed. In the present study, we analyzed data on 1323 cytogenetic assays and 225 subjects examined because of occupational exposures to radon (range of exposure from 1.7 to 662.3 working level month (WLM)). Seventy-five subjects were non-smokers. We found 36 cases of cancer in this cohort. Chromatid breaks were the most frequently observed type of aberrations (mean frequency 1.2 per 100 cells), which statistically significantly correlated with radon exposure (Spearman's correlation coefficient R=0.22, P<0.001). Also, the frequency of aberrant cells (median of 2.5%) correlated with radon exposure (Spearman's correlation coefficient R=0.16, P<0.02). Smoking and silicosis were not associated with results of cytogenetic analyses. The Cox regression models, which accounted for the age at time of first cytogenetic assay, radon exposure, and smoking showed strong and statistically significant associations between cancer incidence and frequency of chromatid breaks and frequency of aberrant cells, respectively. A 1% increase in the frequency of aberrant cells was paralleled by a 62% increase in risk of cancer (P<0.000). An increase in frequency of chromatid breaks by 1 per 100 cells was followed by a 99% increase in risk of cancer (P<0.000). We obtained similar results when we analyzed the incidence of lung cancer and the incidence other than lung cancer separately. Contrary to frequency of chromatid breaks and frequency of aberrant cells, the frequency of chromatid exchanges, and chromosome-type aberrations were not predictive of cancer.

  12. A Comparative Study of Fibroid Ablation Rates Using Radio Frequency or High-Intensity Focused Ultrasound

    SciTech Connect

    Meng Xin; He Guangbin; Zhang Jun; Han Zenghui; Yu Ming; Zhang Miaomiao; Tang Yu; Fang Ling; Zhou Xiaodong

    2010-08-15

    This study compared the technical success of fibroid devascularization using high-intensity focused ultrasound (HIFU) and radio frequency (RF) to provide an experimental basis for the clinical selection of a suitable, minimally invasive method for treating uterine fibroids. Patients were randomly divided into two groups and treated with HIFU or RF accordingly. The two groups of patients were divided again into subgroups A, B, and C based on fibroid diameter and subgroups A', B', and C' based on fibroid blood supply grades. The fibroid diameters in subgroups A, B, and C were 2.0 cm {<=} D < 4.0 cm, 4.0 cm {<=} D<6.0 cm and 6.0 cm {<=} D<8.0 cm, respectively, and fibroid blood supplies were classified into three grades corresponding to subgroups A', B', and C', respectively. The complete ablation rates of the two treatments were compared by contrast-enhanced ultrasound. Both treatments were effective, but the general complete ablation rate of RF was higher than that of HIFU (p < 0.05). The comparison between the two treatments in subgroup A and subgroup A' showed that the complete ablation rate of HIFU was as good as that of RF (p > 0.05). In other subgroups, the complete ablation rates of RF were better than those of HIFU (p < 0.05). No severe complications were observed after these two treatments. RF can be applied for the majority of fibroids. As a noninvasive therapy, HIFU could be the preferred method for the treatment of small, hypovascular fibroids.

  13. Regime shifts in annual maximum rainfall across Australia - implications for intensity-frequency-duration (IFD) relationships

    NASA Astrophysics Data System (ADS)

    Verdon-Kidd, D. C.; Kiem, A. S.

    2015-12-01

    Rainfall intensity-frequency-duration (IFD) relationships are commonly required for the design and planning of water supply and management systems around the world. Currently, IFD information is based on the "stationary climate assumption" that weather at any point in time will vary randomly and that the underlying climate statistics (including both averages and extremes) will remain constant irrespective of the period of record. However, the validity of this assumption has been questioned over the last 15 years, particularly in Australia, following an improved understanding of the significant impact of climate variability and change occurring on interannual to multidecadal timescales. This paper provides evidence of regime shifts in annual maximum rainfall time series (between 1913-2010) using 96 daily rainfall stations and 66 sub-daily rainfall stations across Australia. Furthermore, the effect of these regime shifts on the resulting IFD estimates are explored for three long-term (1913-2010) sub-daily rainfall records (Brisbane, Sydney, and Melbourne) utilizing insights into multidecadal climate variability. It is demonstrated that IFD relationships may under- or over-estimate the design rainfall depending on the length and time period spanned by the rainfall data used to develop the IFD information. It is recommended that regime shifts in annual maximum rainfall be explicitly considered and appropriately treated in the ongoing revisions of the Engineers Australia guide to estimating and utilizing IFD information, Australian Rainfall and Runoff (ARR), and that clear guidance needs to be provided on how to deal with the issue of regime shifts in extreme events (irrespective of whether this is due to natural or anthropogenic climate change). The findings of our study also have important implications for other regions of the world that exhibit considerable hydroclimatic variability and where IFD information is based on relatively short data sets.

  14. Electroacupuncture increased cerebral blood flow and reduced ischemic brain injury: dependence on stimulation intensity and frequency

    PubMed Central

    Zhou, Fei; Guo, Jingchun; Cheng, Jieshi; Wu, Gencheng

    2011-01-01

    Stroke causes ischemic brain injury and is a leading cause of neurological disability and death. There is, however, no promising therapy to protect the brain from ischemic stress to date. Here we show an exciting finding that optimal electroacupuncture (EA) effectively protects the brain from ischemic injury. The experiments were performed on rats subjected to middle cerebral artery occlusion (MCAO) with continuous monitoring of cerebral blood flow. EA was delivered to acupoints of “Shuigou” (Du 26) and “Baihui” (Du 20) with different intensities and frequencies to optimize the stimulation parameters. The results showed that 1) EA at 1.0–1.2 mA and 5–20 Hz remarkably reduced ischemic infarction, neurological deficit, and death rate; 2) the EA treatment increased the blood flow by >100%, which appeared immediately after the initiation of EA and disappeared after the cessation of EA; 3) the EA treatment promoted the recovery of the blood flow after MCAO; 4) “nonoptimal” parameters of EA (e.g., <0.6 mA or >40 Hz) could not improve the blood flow or reduce ischemic injury; and 5) the same EA treatment with optimal parameters could not increase the blood flow in naive brains. These novel observations suggest that appropriate EA treatment protects the brain from cerebral ischemia by increasing blood flow to the ischemic brain region via a rapid regulation. Our findings have far-reaching impacts on the prevention and treatment of ischemic encephalopathy, and the optimized EA parameters may potentially be a useful clue for the clinical application of EA. PMID:21836043

  15. Outcomes for patients with lung cancer admitted to intensive care units

    PubMed Central

    Müller, Alice Mânica; Gazzana, Marcelo Basso; Silva, Denise Rossato

    2013-01-01

    Objective This study aimed to evaluate the outcomes for patients with lung cancer admitted to intensive care units and assess their clinical and demographic profiles. Methods Retrospective, analytical, observational study, wherein the outcomes for patients diagnosed with lung cancer admitted to the intensive care unit of university hospital from January 2010 until February 2011 were evaluated. Results Thirty-four patients' medical records were included. Twenty-six (76.5%) patients received some type of ventilatory support, of whom 21 (61.8%) used invasive mechanical ventilation and 11 (32.4%) used noninvasive ventilation at some point during their stay at the intensive care unit. Regarding mortality, 12 (35.3%) patients died during hospitalization at the intensive care unit, totaling 15 (44.1%) deaths during the entire hospitalization period; 19 (55.9%) patients were discharged from the hospital. The analysis of the variables showed that the patients who died had remained on invasive mechanical ventilation for a longer period 5.0 (0.25 to 15.0) days than the survivors (1.0 (0 to 1.0) days) (p=0.033) and underwent dialysis during their stay at the intensive care unit (p=0.014). Conclusions The mortality of patients with lung cancer admitted to the intensive care unit is associated with the time spent on invasive mechanical ventilation and the need for dialysis. PMID:23887754

  16. Intense, carrier frequency and bandwidth tunable quasi single-cycle pulses from an organic emitter covering the Terahertz frequency gap

    NASA Astrophysics Data System (ADS)

    Vicario, C.; Monoszlai, B.; Jazbinsek, M.; Lee, S.-H.; Kwon, O.-P.; Hauri, C. P.

    2015-09-01

    In Terahertz (THz) science, one of the long-standing challenges has been the formation of spectrally dense, single-cycle pulses with tunable duration and spectrum across the frequency range of 0.1-15 THz (THz gap). This frequency band, lying between the electronically and optically accessible spectra hosts important molecular fingerprints and collective modes which cannot be fully controlled by present strong-field THz sources. We present a method that provides powerful single-cycle THz pulses in the THz gap with a stable absolute phase whose duration can be continuously selected between 68 fs and 1100 fs. The loss-free and chirp-free technique is based on optical rectification of a wavelength-tunable pump pulse in the organic emitter HMQ-TMS that allows for tuning of the spectral bandwidth from 1 to more than 7 octaves over the entire THz gap. The presented source tunability of the temporal carrier frequency and spectrum expands the scope of spectrally dense THz sources to time-resolved nonlinear THz spectroscopy in the entire THz gap. This opens new opportunities towards ultrafast coherent control over matter and light.

  17. Intense, carrier frequency and bandwidth tunable quasi single-cycle pulses from an organic emitter covering the Terahertz frequency gap

    PubMed Central

    Vicario, C.; Monoszlai, B.; Jazbinsek, M.; Lee, S. -H.; Kwon, O. -P.; Hauri, C. P.

    2015-01-01

    In Terahertz (THz) science, one of the long-standing challenges has been the formation of spectrally dense, single-cycle pulses with tunable duration and spectrum across the frequency range of 0.1–15 THz (THz gap). This frequency band, lying between the electronically and optically accessible spectra hosts important molecular fingerprints and collective modes which cannot be fully controlled by present strong-field THz sources. We present a method that provides powerful single-cycle THz pulses in the THz gap with a stable absolute phase whose duration can be continuously selected between 68 fs and 1100 fs. The loss-free and chirp-free technique is based on optical rectification of a wavelength-tunable pump pulse in the organic emitter HMQ-TMS that allows for tuning of the spectral bandwidth from 1 to more than 7 octaves over the entire THz gap. The presented source tunability of the temporal carrier frequency and spectrum expands the scope of spectrally dense THz sources to time-resolved nonlinear THz spectroscopy in the entire THz gap. This opens new opportunities towards ultrafast coherent control over matter and light. PMID:26400005

  18. Acoustic characterization of multi-element, dual-frequency transducers for high-intensity contact ultrasound therapy

    NASA Astrophysics Data System (ADS)

    Burtnyk, M.; N'Djin, W. A.; Persaud, L.; Bronskill, M.; Chopra, R.

    2012-10-01

    High-intensity contact ultrasound therapy can generate precise volumes of thermal damage in deep-seated tissue using interstitial or intracavitary devices. Multi-element, dual-frequency transducers offer increased spatial control of the heating pattern by enabling modulation of ultrasound power and frequency along the device. The performance and acoustic coupling between elements of simple, multi-element, dual-frequency transducers was measured. Transducer arrays were fabricated by cutting halfway through a rectangular plate of PZT, creating individual 4 × 5 mm segments with fundamental frequency (4.1 MHz) and third harmonic (13.3 MHz). Coupling between elements was investigated using a scanning laser vibrometer to measure transducer surface displacements at each frequency and different acoustic powers (0, 10, 20 W/cm2). The measured acoustic power was proportional to the input electrical power with no hysteresis and efficiencies >50% at both frequencies. Maximum transducer surface displacements were observed near element centers, reducing to ˜1/3-maximum near edges. The power and frequency of neighboring transducer segments had little impact on an element's output. In the worst case, an element operating at 4.1 MHz and 20 W/cm2 coupled only 1.5 W/cm2 to its immediate neighboring element. Multi-element, dual-frequency transducers were successfully constructed using a simple dicing method. Coupling between elements was minor, therefore the power and frequency of each transducer element could be considered independent.

  19. Radiation-Induced Cancers From Modern Radiotherapy Techniques: Intensity-Modulated Radiotherapy Versus Proton Therapy

    SciTech Connect

    Yoon, Myonggeun; Ahn, Sung Hwan; Kim, Jinsung; Shin, Dong Ho; Park, Sung Yong; Lee, Se Byeong; Shin, Kyung Hwan; Cho, Kwan Ho

    2010-08-01

    Purpose: To assess and compare secondary cancer risk resulting from intensity-modulated radiotherapy (IMRT) and proton therapy in patients with prostate and head-and-neck cancer. Methods and Materials: Intensity-modulated radiotherapy and proton therapy in the scattering mode were planned for 5 prostate caner patients and 5 head-and-neck cancer patients. The secondary doses during irradiation were measured using ion chamber and CR-39 detectors for IMRT and proton therapy, respectively. Organ-specific radiation-induced cancer risk was estimated by applying organ equivalent dose to dose distributions. Results: The average secondary doses of proton therapy for prostate cancer patients, measured 20-60cm from the isocenter, ranged from 0.4 mSv/Gy to 0.1 mSv/Gy. The average secondary doses of IMRT for prostate patients, however, ranged between 3 mSv/Gy and 1 mSv/Gy, approximately one order of magnitude higher than for proton therapy. Although the average secondary doses of IMRT were higher than those of proton therapy for head-and-neck cancers, these differences were not significant. Organ equivalent dose calculations showed that, for prostate cancer patients, the risk of secondary cancers in out-of-field organs, such as the stomach, lungs, and thyroid, was at least 5 times higher for IMRT than for proton therapy, whereas the difference was lower for head-and-neck cancer patients. Conclusions: Comparisons of organ-specific organ equivalent dose showed that the estimated secondary cancer risk using scattering mode in proton therapy is either significantly lower than the cases in IMRT treatment or, at least, does not exceed the risk induced by conventional IMRT treatment.

  20. Aichi Cancer Center Initial Experience of Intensity Modulated Radiation Therapy for Nasopharyngeal Cancer Using Helical Tomotherapy

    SciTech Connect

    Kodaira, Takeshi Tomita, Natsuo; Tachibana, Hiroyuki; Nakamura, Tatsuya; Nakahara, Rie; Inokuchi, Haruo; Fuwa, Nobukazu

    2009-03-15

    Purpose: To assess the feasibility of helical tomotherapy (HT) for patients with nasopharyngeal carcinoma. Methods and Materials: From June 2006 to June 2007, 20 patients with nasopharyngeal carcinoma were treated with HT with (n = 18) or without (n = 2) systemic chemotherapy. The primary tumor and involved lymph node (PTV1) were prescribed 70 Gy and the prophylactic region 54 Gy at D95, respectively. The majority of patients received 2 Gy per fraction for PTV1 in 35 fractions. Parotid function was evaluated using quantitative scintigraphy at pretreatment, and posttreatment at 3 months and 1 year later. Results: The median patient age was 53 years, ranging from 15 to 83. Our cohort included 5, 8, 4, 2, and 1 patients with disease Stages IIB, III, IVA, IVB, and IVC, respectively. Histopathological record revealed two for World Health Organization Type I and 18 for Type 2 or 3. The median duration time for treatment preparation was 9.5 days, and all plans were thought to be acceptable regarding dose constraints of both the planning target volume and organ at risk. All patients completed their treatment procedure of intensity-modulated radiation therapy (IMRT). All patients achieved clinical remission after IMRT. The majority of patients had Grade 3 or higher toxicity of skin, mucosa, and neutropenia. At the median follow-up of 10.9 months, two patients recurred, and one patient died from cardiac disease. Parotid gland function at 1 year after completion of IMRT was significantly improved compared with that at 3 months. Conclusion: HT was clinically effective in terms of IMRT planning and utility for patients with nasopharyngeal cancer.

  1. Frequency- and intensity-noise suppression in Yb3+-doped single-frequency fiber laser by a passive optical-feedback loop.

    PubMed

    Hou, Yubin; Zhang, Qian; Wang, Pu

    2016-06-13

    The frequency and intensity noise of an Yb3+-doped single-frequency distributed Bragg reflector (DBR) fiber laser are effectively reduced by a simple, passive optical-feedback loop (POFL), which consists of only two optical couplers. The feedback loop, which has resonance with the high reflective grating of the DBR laser and relative long optical path compared to the DBR cavity, results in narrower linewidth and lower relative intensity noise (RIN) in the feedback signal. The RIN of relaxation oscillation is reduced by 20dB from -99.9dB/Hz @ 993 kHz to -119.4dB/Hz @ 192 kHz, and the frequency noise was suppressed at frequencies higher than 1 kHz, with a maximum reduction of about 30 dB from 10 kHz to 100 kHz, which results in a spectral linewidth compression from 3.96 kHz to 540 Hz. Even after one fiber amplification stage, the noise did not increase significantly, and a spectral linewidth well below 1 kHz were also achieved at output power of 10W. PMID:27410318

  2. Effects of climate change on the intensity and frequency of hot spells in northeastern Spain during the 21st century

    NASA Astrophysics Data System (ADS)

    ElKenawy, A. H.; Brunsell, N. A.; Lopez Moreno, J. I.; Vicente-Serrano, S. M.

    2011-12-01

    The intensity and frequency of hot spells in northeastern Spain are simulated using data from ten different RCMs from the PRUDENCE and ENSEMBLE datasets for a control period (1970-2000) and three greenhouse emission scenarios (SRES A1, A2 and B2) for two sub-periods in the 21st century (2020-2050 and 2070-2100). Uncertainty in the predictions has been assessed by means of a set of validation statistics including: mean bias error (MBE), mean absolute error (MAE), root mean square error (RMSE) and D Williomtt statistic. Possible changes in the frequency and intensity of these high-frequency temperature events are projected with the A1, A2 and B2 scenarios. Comparisons between future and control simulations enabled a quantification of these expected changes across the study domain. Our results demonstrate a statistically significant increase in the frequency and intensity of these hot events under the A1 and A2 greenhouse gas emission scenarios. Under these scenarios, considerable spatial variability has also been observed, particularly along the coastal and highly elevated regions (e.g. the Pyrenees). Our results could help to better understanding hot spells snow evolution in the future, which could have potential implications for hydrological modeling, environmental management and various human activities.

  3. Using phase retrieval to measure the intensity and phase of ultrashort pulses: Frequency-resolved optical gating

    SciTech Connect

    Trebino, R. ); Kane, D.J. )

    1993-05-01

    The authors recently introduced a new technique, frequency-resolved optical gating (FROG). For directly determining the full intensity I(t) and phase [var phi](t) of a single femtosecond pulse. By using almost any instantaneous nonlinear-optical interaction of two replicas of the ultrashort pulse to be measured, FROG involves measuring the spectrum of the signal pulse as a function of the delay between the replicas. The resulting trace of intensity versus frequency and delay yields an intuitive display of the pulse that is similar to the pulse spectrogram, except that the gate is a function of the pulse to be measured. The problem of inverting the FROG trace to obtain the pulse intensity and phase can also be considered a complex two-dimensional phase-retrieval problem. As a result, the FROG trace yields, in principle, an essentially unique pulse intensity and phase. It is shown that this is also the case in practice. An iterative-Fourier-transform algorithm is presented for inverting the FROG trace. The algorithm is unusual in its use of a novel constraint: the mathematical form of the signal field. Without the use of a support constraint, the algorithm performs quite well in practice, even for pulses with serious phase distortions and for experimental data with noise, although it occasionally stagnates when pulses with large intensity fluctuations are used. 49 refs., 15 figs.

  4. Increased consultation frequency in primary care, a risk marker for cancer: a case–control study

    PubMed Central

    Ewing, Marcela; Naredi, Peter; Nemes, Szilard; Zhang, Chenyang; Månsson, Jörgen

    2016-01-01

    Objective To identify early diagnostic profiles such as diagnostic codes and consultation patterns of cancer patients in primary care one year prior to cancer diagnosis. Design Total population-based case–control study. Setting and subjects 4562 cancer patients and 17,979 controls matched by age, sex, and primary care unit. Data were collected from the Swedish Cancer Register and the Regional Healthcare Database. Method We identified cancer patients in the Västra Götaland Region of Sweden diagnosed in 2011 with prostate, breast, colorectal, lung, gynaecological, and skin cancers including malignant melanoma. We studied the symptoms and diagnoses identified by diagnostic codes during a diagnostic interval of 12 months before the cancer diagnosis. Main outcome measures Consultation frequency, symptom density by cancer type, prevalence and odds ratios (OR) for the diagnostic codes in the cancer population as a whole. Results The diagnostic codes with the highest OR were unspecified lump in breast, neoplasm of uncertain behaviour, and abnormal serum enzyme levels. The codes with the highest prevalence were hyperplasia of prostate, other skin changes and abdominal and pelvic pain. The frequency of diagnostic codes and consultations in primary care rose in tandem 50 days before diagnosis for breast and gynaecological cancer, 60 days for malignant melanoma and skin cancer, 80 days for prostate cancer and 100 days for colorectal and lung cancer. Conclusion Eighty-seven percent of patients with the most common cancers consulted a general practitioner (GP) a year before their diagnosis. An increase in consultation frequency and presentation of any symptom should raise the GP’s suspicion of cancer. Key pointsKnowledge about the prevalence of early symptoms and other clinical signs in cancer patients in primary care remains insufficient.• Eighty-seven percent of the patients with the seven most common cancers consulted a general practitioner 12 months prior to cancer

  5. Coupled calculation of vibrational frequencies and intensities. Part VI. IR and Raman spectra of crotonaldehyde, methacrolein and methyl-vinylketone

    NASA Astrophysics Data System (ADS)

    Oelichmann, H.-J.; Bougeard, D.; Schrader, B.

    1981-12-01

    The vibrational spectra of trans-crotonaldehyde, methacrolein and methylvinylketone have been reinvestigated and the bands assigned. Normal coordinate analyses of these molecules based on the given assignments have been carried out in the valence force field approximation. A transferable force field for α, β-unsaturated aldehydes and ketones was obtained leading to good agreement between observed and calculated frequencies. The relative cartesian displacements of the atoms given in the L matrices were used to compute the IR and Raman intensities of each mode by a modified CNDO/2 procedure. The intensity calculations confirm the assignments and support the calculated force constants.

  6. High intensity focused ultrasound: A noninvasive therapy for locally advanced pancreatic cancer

    PubMed Central

    Wu, Feng

    2014-01-01

    The noninvasive ablation of pancreatic cancer with high intensity focused ultrasound (HIFU) energy is received increasingly widespread interest. With rapidly temperature rise to cytotoxic levels within the focal volume of ultrasound beams, HIFU can selectively ablate a targeted lesion of the pancreas without any damage to surrounding or overlying tissues. Preliminary studies suggest that this approach is technical safe and feasible, and can be used alone or in combination with systemic chemotherapy for the treatment of patients with locally advanced pancreatic cancer. It can effectively alleviate cancer-related abdominal pain, and may confer an additional survival benefit with few significant complications. This review provides a brief overview of HIFU, describes current clinical applications, summarizes characteristics of continuous and pulsed HIFU, and discusses future applications and challenges in the treatment of pancreatic cancer. PMID:25469016

  7. Assessing dietary intake in childhood cancer survivors: Food frequency questionnaire versus 24-hour diet recalls

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cancer diagnosis and treatment may influence dietary intake. The validity of using self-reported methods to quantify dietary intake has not been evaluated in childhood cancer survivors. We validated total energy intake (EI) reported from Food Frequency Questionnaire (FFQ) and repeated 24-hour diet r...

  8. Method of expected earthquake losses estimation based on the frequency of seismic site intensity

    NASA Astrophysics Data System (ADS)

    Gao, Meng-Tan

    1995-05-01

    During a given period, a site will suffer the attack from earthquake several times. But this effect is neglected in the currently used model of loss estimation from earthquake. When calculating the occurrence rate of the affected intensity, the difference of the exceeding probability is used. Such treatment will underestimate the earthquake loss, especially when the exposure period is long. To overcome the shortcomings of the model currently used, a new frame of earthquake loss estimation is provided from the logic sense: during the given period, the expected earthquake loss responding to the specific affected intensity is equal to the expected number of the intensity multiplying the expected loss under the condition of such an affected intensity, and the total expected loss is equal to the effects of all the possible intensities. On the basis of the seismicity model used in compiling the “ Chinese Seismic Intensity Zoning Map (1990)”, a new formula of expected loss evaluation and the variance of the evaluation are provided. It is inferred from the example and the comparison with the currently used method that the new method is applicable and necessary. These results will lay a scientific foundation for the estimation of earthquake loss, insurance and disaster prevention.

  9. Spatial Intensity Duration Frequency Relationships Using Hierarchical Bayesian Analysis for Urban Areas

    NASA Astrophysics Data System (ADS)

    Rupa, Chandra; Mujumdar, Pradeep

    2016-04-01

    In urban areas, quantification of extreme precipitation is important in the design of storm water drains and other infrastructure. Intensity Duration Frequency (IDF) relationships are generally used to obtain design return level for a given duration and return period. Due to lack of availability of extreme precipitation data for sufficiently large number of years, estimating the probability of extreme events is difficult. Typically, a single station data is used to obtain the design return levels for various durations and return periods, which are used in the design of urban infrastructure for the entire city. In an urban setting, the spatial variation of precipitation can be high; the precipitation amounts and patterns often vary within short distances of less than 5 km. Therefore it is crucial to study the uncertainties in the spatial variation of return levels for various durations. In this work, the extreme precipitation is modeled spatially using the Bayesian hierarchical analysis and the spatial variation of return levels is studied. The analysis is carried out with Block Maxima approach for defining the extreme precipitation, using Generalized Extreme Value (GEV) distribution for Bangalore city, Karnataka state, India. Daily data for nineteen stations in and around Bangalore city is considered in the study. The analysis is carried out for summer maxima (March - May), monsoon maxima (June - September) and the annual maxima rainfall. In the hierarchical analysis, the statistical model is specified in three layers. The data layer models the block maxima, pooling the extreme precipitation from all the stations. In the process layer, the latent spatial process characterized by geographical and climatological covariates (lat-lon, elevation, mean temperature etc.) which drives the extreme precipitation is modeled and in the prior level, the prior distributions that govern the latent process are modeled. Markov Chain Monte Carlo (MCMC) algorithm (Metropolis Hastings

  10. Frequency of TERT promoter mutations in human cancers.

    PubMed

    Vinagre, João; Almeida, Ana; Pópulo, Helena; Batista, Rui; Lyra, Joana; Pinto, Vasco; Coelho, Ricardo; Celestino, Ricardo; Prazeres, Hugo; Lima, Luis; Melo, Miguel; da Rocha, Adriana Gaspar; Preto, Ana; Castro, Patrícia; Castro, Ligia; Pardal, Fernando; Lopes, José Manuel; Santos, Lúcio Lara; Reis, Rui Manuel; Cameselle-Teijeiro, José; Sobrinho-Simões, Manuel; Lima, Jorge; Máximo, Valdemar; Soares, Paula

    2013-01-01

    Reactivation of telomerase has been implicated in human tumorigenesis, but the underlying mechanisms remain poorly understood. Here we report the presence of recurrent somatic mutations in the TERT promoter in cancers of the central nervous system (43%), bladder (59%), thyroid (follicular cell-derived, 10%) and skin (melanoma, 29%). In thyroid cancers, the presence of TERT promoter mutations (when occurring together with BRAF mutations) is significantly associated with higher TERT mRNA expression, and in glioblastoma we find a trend for increased telomerase expression in cases harbouring TERT promoter mutations. Both in thyroid cancers and glioblastoma, TERT promoter mutations are significantly associated with older age of the patients. Our results show that TERT promoter mutations are relatively frequent in specific types of human cancers, where they lead to enhanced expression of telomerase. PMID:23887589

  11. Modulation-frequency dependencies of the intensity and the phase delay of photoinduced absorption from conjugated polymers

    NASA Astrophysics Data System (ADS)

    Furukawa, Yukio

    2000-03-01

    The modulation-frequency dependencies of the intensity and the phase delay of photoinduced infrared absorption from poly(p-phenylene) have been observed and simulated numerically on the basis of a model based on second-order kinetics involving a neutralization recombination process between the positive and negative charge carriers (polarons) that are formed from a photogenerated polaron pair (interchain charge-transfer exciton). The rate constant of the bimolecular recombination has been obtained.

  12. The mechanism of modulation of geoacoustic emission intensity by weak electromagnetic fields in the audio-frequency range

    NASA Astrophysics Data System (ADS)

    Gavrilov, V. A.

    2016-07-01

    We propose a physical mechanism explaining the mechanism of modulation of the geoacoustic emission intensity by an external electromagnetic field in the audio-frequency range, which was previously revealed as a result of borehole measurements at the Petropavlovsk-Kamchatskii geodynamic testing area. It was established that electric double layers (EDL) at the interface between solid and liquid phases in a fluidsaturated geological medium play a key role in the mechanism proposed.

  13. Racial Differences in Diffusion of Intensity-Modulated Radiation Therapy for Localized Prostate Cancer.

    PubMed

    Cobran, Ewan K; Chen, Ronald C; Overman, Robert; Meyer, Anne-Marie; Kuo, Tzy-Mey; O'Brien, Jonathon; Sturmer, Til; Sheets, Nathan C; Goldin, Gregg H; Penn, Dolly C; Godley, Paul A; Carpenter, William R

    2016-09-01

    Intensity-modulated radiation therapy (IMRT), an innovative treatment option for prostate cancer, has rapidly diffused over the past decade. To inform our understanding of racial disparities in prostate cancer treatment and outcomes, this study compared diffusion of IMRT in African American (AA) and Caucasian American (CA) prostate cancer patients during the early years of IMRT diffusion using the Surveillance, Epidemiology and End Results (SEER)-Medicare linked database. A retrospective cohort of 947 AA and 10,028 CA patients diagnosed with localized prostate cancer from 2002 through 2006, who were treated with either IMRT or non-IMRT as primary treatment within 1 year of diagnoses was constructed. Logistic regression was used to examine potential differences in diffusion of IMRT in AA and CA patients, while adjusting for socioeconomic and clinical covariates. A significantly smaller proportion of AA compared with CA patients received IMRT for localized prostate cancer (45% vs. 53%, p < .0001). Racial differences were apparent in multivariable analysis though did not achieve statistical significance, as time and factors associated with race (socioeconomic, geographic, and tumor related factors) explained the preponderance of variance in use of IMRT. Further research examining improved access to innovative cancer treatment and technologies is essential to reducing racial disparities in cancer care.

  14. A Distributed Network for Intensive Longitudinal Monitoring in Metastatic Triple-Negative Breast Cancer.

    PubMed

    Blau, C Anthony; Ramirez, Arturo B; Blau, Sibel; Pritchard, Colin C; Dorschner, Michael O; Schmechel, Stephen C; Martins, Timothy J; Mahen, Elisabeth M; Burton, Kimberly A; Komashko, Vitalina M; Radenbaugh, Amie J; Dougherty, Katy; Thomas, Anju; Miller, Christopher P; Annis, James; Fromm, Jonathan R; Song, Chaozhong; Chang, Elizabeth; Howard, Kellie; Austin, Sharon; Schmidt, Rodney A; Linenberger, Michael L; Becker, Pamela S; Senecal, Francis M; Mecham, Brigham H; Lee, Su-In; Madan, Anup; Ronen, Roy; Dutkowski, Janusz; Heimfeld, Shelly; Wood, Brent L; Stilwell, Jackie L; Kaldjian, Eric P; Haussler, David; Zhu, Jingchun

    2016-01-01

    Accelerating cancer research is expected to require new types of clinical trials. This report describes the Intensive Trial of OMics in Cancer (ITOMIC) and a participant with triple-negative breast cancer metastatic to bone, who had markedly elevated circulating tumor cells (CTCs) that were monitored 48 times over 9 months. A total of 32 researchers from 14 institutions were engaged in the patient's evaluation; 20 researchers had no prior involvement in patient care and 18 were recruited specifically for this patient. Whole-exome sequencing of 3 bone marrow samples demonstrated a novel ROS1 variant that was estimated to be present in most or all tumor cells. After an initial response to cisplatin, a hypothesis of crizotinib sensitivity was disproven. Leukapheresis followed by partial CTC enrichment allowed for the development of a differential high-throughput drug screen and demonstrated sensitivity to investigational BH3-mimetic inhibitors of BCL-2 that could not be tested in the patient because requests to the pharmaceutical sponsors were denied. The number and size of CTC clusters correlated with clinical status and eventually death. Focusing the expertise of a distributed network of investigators on an intensively monitored patient with cancer can generate high-resolution views of the natural history of cancer and suggest new opportunities for therapy. Optimization requires access to investigational drugs. PMID:26733551

  15. A Distributed Network for Intensive Longitudinal Monitoring in Metastatic Triple-Negative Breast Cancer.

    PubMed

    Blau, C Anthony; Ramirez, Arturo B; Blau, Sibel; Pritchard, Colin C; Dorschner, Michael O; Schmechel, Stephen C; Martins, Timothy J; Mahen, Elisabeth M; Burton, Kimberly A; Komashko, Vitalina M; Radenbaugh, Amie J; Dougherty, Katy; Thomas, Anju; Miller, Christopher P; Annis, James; Fromm, Jonathan R; Song, Chaozhong; Chang, Elizabeth; Howard, Kellie; Austin, Sharon; Schmidt, Rodney A; Linenberger, Michael L; Becker, Pamela S; Senecal, Francis M; Mecham, Brigham H; Lee, Su-In; Madan, Anup; Ronen, Roy; Dutkowski, Janusz; Heimfeld, Shelly; Wood, Brent L; Stilwell, Jackie L; Kaldjian, Eric P; Haussler, David; Zhu, Jingchun

    2016-01-01

    Accelerating cancer research is expected to require new types of clinical trials. This report describes the Intensive Trial of OMics in Cancer (ITOMIC) and a participant with triple-negative breast cancer metastatic to bone, who had markedly elevated circulating tumor cells (CTCs) that were monitored 48 times over 9 months. A total of 32 researchers from 14 institutions were engaged in the patient's evaluation; 20 researchers had no prior involvement in patient care and 18 were recruited specifically for this patient. Whole-exome sequencing of 3 bone marrow samples demonstrated a novel ROS1 variant that was estimated to be present in most or all tumor cells. After an initial response to cisplatin, a hypothesis of crizotinib sensitivity was disproven. Leukapheresis followed by partial CTC enrichment allowed for the development of a differential high-throughput drug screen and demonstrated sensitivity to investigational BH3-mimetic inhibitors of BCL-2 that could not be tested in the patient because requests to the pharmaceutical sponsors were denied. The number and size of CTC clusters correlated with clinical status and eventually death. Focusing the expertise of a distributed network of investigators on an intensively monitored patient with cancer can generate high-resolution views of the natural history of cancer and suggest new opportunities for therapy. Optimization requires access to investigational drugs.

  16. A Distributed Network for Intensive Longitudinal Monitoring in Metastatic Triple-Negative Breast Cancer

    PubMed Central

    Blau, C. Anthony; Ramirez, Arturo B.; Blau, Sibel; Pritchard, Colin C.; Dorschner, Michael O.; Schmechel, Stephen C.; Martins, Timothy J.; Mahen, Elisabeth M.; Burton, Kimberly A.; Komashko, Vitalina M.; Radenbaugh, Amie J.; Dougherty, Katy; Thomas, Anju; Miller, Christopher P.; Annis, James; Fromm, Jonathan R.; Song, Chaozhong; Chang, Elizabeth; Howard, Kellie; Austin, Sharon; Schmidt, Rodney A.; Linenberger, Michael L.; Becker, Pamela S.; Senecal, Francis M.; Mecham, Brigham H.; Lee, Su-In; Madan, Anup; Ronen, Roy; Dutkowski, Janusz; Heimfeld, Shelly; Wood, Brent L.; Stilwell, Jackie L.; Kaldjian, Eric P.; Haussler, David; Zhu, Jingchun

    2016-01-01

    Accelerating cancer research is expected to require new types of clinical trials. This report describes the Intensive Trial of OMics in Cancer (ITOMIC) and a participant with triple-negative breast cancer metastatic to bone, who had markedly elevated circulating tumor cells (CTCs) that were monitored 48 times over 9 months. A total of 32 researchers from 14 institutions were engaged in the patient’s evaluation; 20 researchers had no prior involvement in patient care and 18 were recruited specifically for this patient. Whole-exome sequencing of 3 bone marrow samples demonstrated a novel ROS1 variant that was estimated to be present in most or all tumor cells. After an initial response to cisplatin, a hypothesis of crizotinib sensitivity was disproven. Leukapheresis followed by partial CTC enrichment allowed for the development of a differential high-throughput drug screen and demonstrated sensitivity to investigational BH3-mimetic inhibitors of BCL-2 that could not be tested in the patient because requests to the pharmaceutical sponsors were denied. The number and size of CTC clusters correlated with clinical status and eventually death. Focusing the expertise of a distributed network of investigators on an intensively monitored patient with cancer can generate high-resolution views of the natural history of cancer and suggest new opportunities for therapy. Optimization requires access to investigational drugs. PMID:26733551

  17. Observations of a free-energy source for intense electrostatic waves. [in upper atmosphere near upper hybrid resonance frequency

    NASA Technical Reports Server (NTRS)

    Kurth, W. S.; Frank, L. A.; Gurnett, D. A.; Burek, B. G.; Ashour-Abdalla, M.

    1980-01-01

    Significant progress has been made in understanding intense electrostatic waves near the upper hybrid resonance frequency in terms of the theory of multiharmonic cyclotron emission using a classical loss-cone distribution function as a model. Recent observations by Hawkeye 1 and GEOS 1 have verified the existence of loss-cone distributions in association with the intense electrostatic wave events, however, other observations by Hawkeye and ISEE have indicated that loss cones are not always observable during the wave events, and in fact other forms of free energy may also be responsible for the instability. Now, for the first time, a positively sloped feature in the perpendicular distribution function has been uniquely identified with intense electrostatic wave activity. Correspondingly, we suggest that the theory is flexible under substantial modifications of the model distribution function.

  18. Influence of different frequencies of transcutaneous electrical nerve stimulation on the threshold and pain intensity in young subjects

    PubMed Central

    Gomes, Adriana de Oliveira; Silvestre, Ana Caroline; da Silva, Cristina Ferreira; Gomes, Mariany Ribeiro; Bonfleur, Maria Lúcia; Bertolini, Gladson Ricardo Flor

    2014-01-01

    Objective To investigate the effects of different transcutaneous electrical nerve stimulation frequencies in nociception front of a pressure pain threshold and cold in healthy individuals. Methods Twenty healthy subjects were divided into four groups, all of which have gone through all forms of electrical stimulation at different weeks. Assessments were pre and post-therapy, 20 and 60 minutes after stimulation. To evaluate the pressure pain threshold, an algometer was used with one tapered tip, pressing the hypothenar region until voluntary report the word “pain”. Cold pain intensity was assessed by immersion in water at 5°C for 30 seconds; at the end, the subject was asked to quantify the pain intensity on a Visual Analog Scale for Pain. For electrical stimulation, two electrodes were used near the elbow, for 20 minutes, with an intensity strong, but not painful. The frequency was in accordance with the group: 0Hz (placebo); 7Hz; 100Hz; and 255Hz. Results Both for the assessment of pressure pain threshold as the cold pain intensity, there was no significant difference (p>0.05). Conclusion We conclude that the use of transcutaneous electrical nerve stimulation on dermatomes C6 to C8 produced no significant change in pressure pain threshold or cold discomfort. PMID:25295453

  19. Associations between psychosocial functioning and smiling intensity in patients with head and neck cancer.

    PubMed

    Lee, Juhun; Teo, Irene; Guindani, Michele; Reece, Gregory P; Markey, Mia K; Fingeret, Michelle Cororve

    2015-01-01

    Increasing attention is being given to developing quantitative measures of facial expression. This study used quantitative facial expression analysis to examine associations between smiling intensity and psychosocial functioning in patients with head and neck cancer (HNC). Smiling intensity of 95 HNC patients was measured using 48 quantitative measures calculated from facial photographs with and without a smile. We computed a composite smiling intensity score for each patient representing the degree of similarity to healthy controls. A lower composite score indicates that the person is less expressive, on average, than healthy controls. Patients also completed self-report measures assessing domains of body image and quality of life (QOL). Spearman rank correlations were computed to examine relationships between composite scores and psychosocial functioning. Composite scores were significantly correlated with multiple measures of body image and QOL. Specifically, decreased smiling intensity was associated with feelings of dissatisfaction with one's body, perceived negative social impact of body image, increased use of avoidance as a body image-coping strategy, reduced functional well-being, and greater head and neck cancer-specific issues. To the best of our knowledge, this is the first study to demonstrate associations between an objectively quantified facial expression (i.e. smiling) and psychosocial functioning. Most previous studies have measured facial expression qualitatively. These findings indicate that smiling intensity may serve as an important clinical indicator of psychosocial well-being and warrants further clinical investigation.

  20. Intense Low-frequency Chorus Waves Observed by Van Allen Probes: Fine Structures and Potential Effect on Radiation Belt Electrons

    NASA Astrophysics Data System (ADS)

    Gao, Z.; Su, Z.; Zhu, H.

    2015-12-01

    Whistler-mode chorus emission in the low-density plasmatrough contributes significantly to the radiation belt electron dynamics. Chorus was usually considered to occur in the frequency range 0.1-0.8 fce (with the equatorial electron gyrofrequency fce ). We here report an event of intense low-frequency chorus with nearly half of wave power distributed below 0.1 fce observed by the Van Allen Probes on 27 August 2014. This emission exhibited little discrete rising tones but mainly the hiss-like signatures, had the high ellipticity of ˜1 and propagated quasi-parallel to the magnetic field. Compared with the typical chorus, the low-frequency chorus can produce weaker (2 times at ~ MeV and even up to several orders of magnitude at ~0.1MeV) momentum diffusion of the near-equatorially trapped electrons, but much stronger (1-2 orders of magnitude) pitch-angle diffusion near the loss cone. The acceleration and particularly loss effect of such intense low-frequency chorus may need to be taken into account in future radiation belt models.

  1. Conventional and Kilohertz-frequency Spinal Cord Stimulation Produces Intensity- and Frequency-dependent Inhibition of Mechanical Hypersensitivity in a Rat Model of Neuropathic Pain

    PubMed Central

    Shechter, Ronen; Yang, Fei; Xu, Qian; Cheong, Yong-Kwan; He, Shao-Qiu; Sdrulla, Andrei; Carteret, Alene F.; Wacnik, Paul W.; Dong, Xinzhong; Meyer, Richard A.; Raja, Srinivasa N.; Guan, Yun

    2013-01-01

    Background Spinal cord stimulation (SCS) is a useful neuromodulatory technique for treatment of certain neuropathic pain conditions. However, the optimal stimulation parameters remain unclear. Methods In rats after L5 spinal nerve ligation, we compared the inhibitory effects on mechanical hypersensitivity from bipolar SCS of different intensities (20%, 40%, 80% motor threshold) and frequencies (50-Hz, 1-kHz, and 10-kHz). We then compared the effects of 1-kHz and 50-Hz dorsal column stimulation at high and low stimulus intensities on conduction properties of afferent Aα/β-fibers and spinal wide-dynamic-range neuronal excitability. Results Three consecutive daily SCS at different frequencies progressively inhibited mechanical hypersensitivity in an intensity-dependent manner. At 80% motor threshold, the ipsilateral paw withdrawal threshold (%preinjury) increased significantly from pre-SCS measures, beginning with the first day of SCS at the frequencies of 1-kHz (50.2 ± 5.7% from 23.9 ± 2.6%, n = 19, mean ± SEM) and 10-kHz (50.8 ± 4.4 % from 27.9 ± 2.3%, n = 17), while it was significantly increased beginning on the second day in the 50-Hz group (38.9 ± 4.6% from 23.8 ± 2.1%, n = 17). At high intensity, both 1-kHz and 50-Hz dorsal column stimulation reduced Aα/β-compound action potential size recorded at the sciatic nerve, but only 1-kHz stimulation was partially effective at the lower intensity. The number of actions potentials in C-fiber component of wide-dynamic-range neuronal response to windup-inducing stimulation was significantly decreased after 50-Hz (147.4 ± 23.6 from 228.1 ± 39.0, n = 13), but not 1-kHz (n = 15), dorsal column stimulation. Conclusions Kilohertz SCS attenuated mechanical hypersensitivity in a time course and amplitude that differed from conventional 50-Hz SCS, and may involve different peripheral and spinal segmental mechanisms. PMID:23880991

  2. Fiber optic sensing systems using high frequency resonant sensing heads with intensity sensors

    NASA Technical Reports Server (NTRS)

    Adamovsky, Grigory; Maitland, Duncan J., IV

    1988-01-01

    Optical fibers have an inherent capability of transmitting high bandwidth analog and digital signals. To apply this property of fiber optics to remote sensing, special sensing heads as well as signal processing electronics have to be developed. In systems employing intensity modulating sensors, there is also a need for a referencing technique to compensate for changes in the transmission of the connecting fibers and light source intensity. Fiber optic sensing systems incorporated in sensing heads of a special configuration are discussed. Different modes of operation as well as resonant conditions are explained. Theoretical and experimental analyses are also given.

  3. [Antitumor effect of low-intensity extremely high-frequency electromagnetic radiation on a model of solid Ehrlich carcinoma].

    PubMed

    Gapeev, A B; Shved, D M; Mikhaĭlik, E N; Korystov, Iu N; Levitman, M Kh; Shaposhnikova, V V; Sadovnikov, V B; Alekhin, A I; Goncharov, N G; Chemeris, N K

    2009-01-01

    The influence of different exposure regimes of low-intensity extremely high-frequency electromagnetic radiation on the growth rate of solid Ehrlich carcinoma in mice has been studied. It was shown that, at an optimum repetition factor of exposure (20 min daily for five consecutive days after the tumor inoculation), there is a clearly pronounced frequency dependence of the antitumor effect. The analysis of experimental data indicates that the mechanisms of antitumor effects of the radiation may be related to the modification of the immune status of the organism. The results obtained show that extremely high-frequency electromagnetic radiation at a proper selection of exposure regimes can result in distinct and stable antitumor effects.

  4. High-Frequency, Moderate-Intensity Training in Sedentary Middle-Aged Women.

    ERIC Educational Resources Information Center

    Johannessen, S.; And Others

    1986-01-01

    The effects of a five-day-a-week, moderate-intensity aerobic training program were studied in previously sedentary middle-aged women. After 10 weeks of graduated-length sessions of continuous exercise, the subjects showed a 20 percent improvement in maximal oxygen uptake but no change in body weight or composition. Results are discussed.…

  5. Assessing Dietary Intake in Childhood Cancer Survivors: Food Frequency Questionnaire Versus 24-Hour Diet Recalls.

    PubMed

    Zhang, Fang Fang; Roberts, Susan B; Must, Aviva; Wong, William W; Gilhooly, Cheryl H; Kelly, Michael J; Parsons, Susan K; Saltzman, Edward

    2015-10-01

    Cancer diagnosis and treatment may influence dietary intake. The validity of using self-reported methods to quantify dietary intake has not been evaluated in childhood cancer survivors. We validated total energy intake (EI) reported from Food Frequency Questionnaire (FFQ) and repeated 24-hour diet recalls (24HRs) against total energy expenditure (TEE) measured using the doubly labeled water method in 16 childhood cancer survivors. Dietary underreporting, assessed by (EI-TEE)/TEE × 100%, was 22% for FFQ and 1% for repeated 24HRs. FFQ significantly underestimates dietary intake and should not be used to assess the absolute intake of foods and nutrients in childhood cancer survivors.

  6. Assessing Dietary Intake in Childhood Cancer Survivors: Food Frequency Questionnaire versus 24-Hour Diet Recalls

    PubMed Central

    Zhang, Fang Fang; Roberts, Susan B.; Must, Aviva; Wong, William W.; Gilhooly, Cheryl H.; Kelly, Michael J.; Parsons, lkSusan K.; Saltzman, Edward

    2015-01-01

    Cancer diagnosis and treatment may influence dietary intake. The validity of using self-reported methods to quantify dietary intake has not been evaluated in childhood cancer survivors. We validated total energy intake (EI) reported from food frequency questionnaire (FFQ) and repeated 24-hour diet recalls (24HRs) against total energy expenditure (TEE) measured using the doubly labeled water method in 16 childhood cancer survivors. Dietary underreporting, assessed by (EI-TEE)/TEE ×100%, was 22% for FFQ and 1% for repeated 24HRs. FFQ significantly underestimates dietary intake and should not be used to assess the absolute intake of foods and nutrients in childhood cancer survivors. PMID:25883059

  7. Taste intensity and hedonic responses to simple beverages in gastrointestinal cancer patients.

    PubMed

    Bossola, Maurizio; Cadoni, Gabriella; Bellantone, Rocco; Carriero, Concetta; Carriero, Elena; Ottaviani, Fabrizio; Borzomati, Domenico; Tortorelli, Antonio; Doglietto, Giovan Battista

    2007-11-01

    Changes in the taste of food have been implicated as a potential cause of reduced dietary intake among cancer patients. However, data on intensity and hedonic responses to the four basic tastes in cancer are scanty and contradictory. The present study aimed at evaluating taste intensity and hedonic responses to simple beverages in 47 anorectic patients affected by gastrointestinal cancer and in 55 healthy subjects. Five suprathreshold concentrations of each of the four test substances (sucrose in black current drinks, citric acid in lemonade, NaCl in unsalted tomato juice, and urea in tonic water) were used. Patients were invited to express a judgment of intensity and pleasantness ranging from 0 to 10. Mean intensity scores directly correlated with concentrations of sour, salty, bitter, and sweet stimuli, in both normals and those with cancer. Intensity judgments were higher in cancer patients with respect to sweet (for median and high concentrations, P<0.05), salty (for all concentrations, P<0.05), and bitter tastes (for median concentration, P<0.01). Hedonic function increased with the increase of the stimuli only for the sweet taste. A negative linear correlation was found between sour, bitter, and salty concentrations and hedonic score. Both in cancer patients and in healthy subjects, hedonic judgments increased with the increase of the stimulus for the sweet taste (r=0.978 and r=0.985, P=0.004 and P=0.002, respectively), and decreased for the salty (r=-0.827 and r=-0.884, P=0.084 and P=0.047, respectively) and bitter tastes (r=-0.990 and r=-0.962, P=0.009 and P=0.001, respectively). For the sour taste, the hedonic scores remained stable with the increase of the stimulus in noncancer controls (r=-0.785, P=0.115) and decreased in cancer patients (r=-0.996, P=0.0001). The hedonic scores for the sweet taste and the bitter taste were similar in cancer patients and healthy subjects, and these scores were significantly higher in cancer patients than in healthy

  8. Intense high-frequency gyrotron-based microwave beams for material processing

    SciTech Connect

    Hardek, T.W.; Cooke, W.D.; Katz, J.D.; Perry, W.L.; Rees, D.E.

    1997-03-01

    Microwave processing of materials has traditionally utilized frequencies in the 0.915 and 2.45 GHz regions. Microwave power sources are readily available at these frequencies but the relatively long wavelengths can present challenges in uniformly heating materials. An additional difficulty is the poor coupling of ceramic based materials to the microwave energy. Los Alamos National Laboratory scientists, working in conjunction with the National Center for Manufacturing Sciences (NCMS), have assembled a high-frequency demonstration processing facility utilizing gyrotron based RF sources. The facility is primarily intended to demonstrate the unique features available at frequencies as high as 84 GHz. The authors can readily provide quasi-optical, 37 GHz beams at continuous wave (CW) power levels in the 10 kW range. They have also provided beams at 84 GHz at 10 kW CW power levels. They are presently preparing a facility to demonstrate the sintering of ceramics at 30 GHz. This paper presents an overview of the present demonstration processing facility and describes some of the features they have available now and will have available in the near future.

  9. Clinical evaluation of intensity-modulated radiotherapy for head and neck cancers

    PubMed Central

    Bhide, S A; Newbold, K L; Harrington, K J; Nutting, C M

    2012-01-01

    Radiotherapy and surgery are the principal curative modalities in treatment of head and neck cancer. Conventional two-dimensional and three-dimensional conformal radiotherapy result in significant side effects and altered quality of life. Intensity-modulated radiotherapy (IMRT) can spare the normal tissues, while delivering a curative dose to the tumour-bearing tissues. This article reviews the current role of IMRT in head and neck cancer from the point of view of normal tissue sparing, and also reviews the current published literature by individual head and neck cancer subsites. In addition, we briefly discuss the role of image guidance in head and neck IMRT, and future directions in this area. PMID:22556403

  10. Clinical Application of High-intensity Focused Ultrasound in Cancer Therapy

    PubMed Central

    Hsiao, Yi-Hsuan; Kuo, Shou-Jen; Tsai, Horng-Der; Chou, Ming-Chih; Yeh, Guang-Perng

    2016-01-01

    The treatment of cancer is an important issue in both developing and developed countries. Clinical use of ultrasound in cancer is not only for the diagnosis but also for the treatment. Focused ultrasound surgery (FUS) is a noninvasive technique. By using the combination of high-intensity focused ultrasound (HIFU) and imaging method, FUS has the potential to ablate tumor lesions precisely. The main mechanisms of HIFU ablation involve mechanical and thermal effects. Recent advances in HIFU have increased its popularity. Some promising results were achieved in managing various malignancies, including pancreas, prostate, liver, kidney, breast and bone. Other applications include brain tumor ablation and disruption of the blood-brain barrier. We aim at briefly outlining the clinical utility of FUS as a noninvasive technique for a variety of types of cancer treatment. PMID:26918034

  11. Intense low-frequency chorus waves observed by Van Allen Probes: Fine structures and potential effect on radiation belt electrons

    NASA Astrophysics Data System (ADS)

    Gao, Zhonglei; Su, Zhenpeng; Zhu, Hui; Xiao, Fuliang; Zheng, Huinan; Wang, Yuming; Shen, Chao; Wang, Shui

    2016-02-01

    Frequency distribution is a vital factor in determining the contribution of whistler mode chorus to radiation belt electron dynamics. Chorus is usually considered to occur in the frequency range 0.1-0.8fce_eq (with the equatorial electron gyrofrequency fce_eq). We here report an event of intense low-frequency chorus with nearly half of wave power distributed below 0.1fce_eq observed by Van Allen Probe A on 27 August 2014. This emission propagated quasi-parallel to the magnetic field and exhibited hiss-like signatures most of the time. The low-frequency chorus can produce the rapid loss of low-energy (˜0.1 MeV) electrons, different from the normal chorus. For high-energy (≥0.5 MeV) electrons, the low-frequency chorus can yield comparable momentum diffusion to that of the normal chorus but much stronger (up to 2 orders of magnitude) pitch angle diffusion near the loss cone.

  12. Exercise Intensity Guidelines for Cancer Survivors: a Comparison with Reference Values.

    PubMed

    Gil-Rey, E; Quevedo-Jerez, K; Maldonado-Martin, S; Herrero-Román, F

    2014-11-27

    The optimal dose of physical activity (PA) in cancer survivors (CS) is unknown due to the large variety of types of cancer, illness stages and treatments, low cardiorespiratory fitness, and physical inactivity. It is recommended that CS follow current PA guidelines for healthy population. There are no specific exercise prescription guidelines for CS. To know the cardiorespiratory parameters of CS in order to create exercise prescription guidelines for this population, 152 inactive CS were recruited to perform a cardiopulmonary exercise test. Peak oxygen uptake (VO2peak), ventilatory threshold (VT) and respiratory compensation point (RCP) determined 3 exercise intensity zones to create exercise intensity classification guidelines for CS. VO2peak (18.7±4.6 mL·kg(-1)·min(-1)) and peak heart rate (HRpeak) (145.1±17.9 bpm) were lower than the estimated values (p<0.001). Moderate intensity zone for CS was different from the current PA guidelines for healthy population: 41-64% VO2max, 55-70% HRmax, 23-48% HRres, 2.5-4 METs and 8-14 points on RPE scale. Intensities in PA guidelines for healthy population are not adapted to the characteristics of CS. For individual exercise prescription in CS specific PA guidelines should be used in order to maximize the benefits obtained by the use of aerobic exercise training.

  13. On the Annual Frequency of Intense Hurricanes in Relation to the Extremes of ENSO and the Interludes Between Them

    NASA Technical Reports Server (NTRS)

    Wilson, Robert M.

    1998-01-01

    On the basis of Trenberth's quantitative definition for marking the occurrence of an El Nino, one can precisely identify some 15 El Nino and 10 La Nina events during the interval of 1950-1997. The statistical aspects of these identified extremes and the intervening periods between them (interludes) are determined. Also, a comparison of the appearances of these extremes and interludes with yearly hurricane seasons shows that of the last 48 hurricane seasons, 20 (42%) are El Nino-related (i.e., an El Nino was in progress during all, or part, of the yearly hurricane season - June-November), 13 (27%) are La Nina-related, and 15 (31%) are interlude - related. Combining the two subgroups of La Nino- and interlude - related seasons into a single grouping called non-El Nino-related seasons, one finds that the non-El Nino-related seasons have a mean annual frequency of intense hurricanes measuring 2.8, while the El Nino-related seasons have a mean annual frequency of intense hurricanes measuring 1.3, and the observed difference in the means is inferred to be statistically important at the 99.8% level of confidence. Therefore, during El Nino-related seasons, fewer intense hurricanes (typically, less than or equal to 2) should be expected, while durin(y non-El Nino-related seasons, more (typically, greater than or equal to 2) should be expected. Implications for the upcoming 1998 and future hurricane seasons are discussed.

  14. High-Frequency, Low-Intensity Pulsed Ultrasound Enhances Alveolar Bone Healing of Extraction Sockets in Rats: A Pilot Study.

    PubMed

    Kang, Kyung Lhi; Kim, Eun-Cheol; Park, Joon Bong; Heo, Jung Sun; Choi, Yumi

    2016-02-01

    Most studies of the beneficial effects of low-intensity pulsed ultrasound (LIPUS) on bone healing have used frequencies between 1.0 and 1.5 MHz. However, after consideration of ultrasound wave characteristics and depth of target tissue, higher-frequency LIPUS may have been more effective on superficially positioned alveolar bone. We investigated this hypothesis by applying LIPUS (frequency, 3.0 MHz; intensity, 30 mW/cm(2)) on shaved right cheeks over alveolar bones of tooth extraction sockets in rats for 10 min/d for 2 wk after tooth extraction; the control group (left cheek of the same rats) did not receive LIPUS treatment. Compared with the control group, the LIPUS group manifested more new bone growth inside the sockets on histomorphometric analysis (maximal difference = 2.5-fold on the seventh day after extraction) and higher expressions of osteogenesis-related mRNAs and proteins than the control group did. These findings indicate that 3.0-MHz LIPUS could enhance alveolar bone formation and calcification in rats.

  15. Total intensity data in geomagnetic fields locate earthquakes by using the frequency wavenumber analysis in Taiwan

    NASA Astrophysics Data System (ADS)

    Chen, C.; Liu, J.; Chang, T.; Yen, H.

    2008-12-01

    In this paper, a magnetic network with eight magnetometers is employed in detecting the 3 earthquake (Ml>=5.5) locations in Taiwan. To determine the earthquake epicenter, the northern and southern arrays are separated from the network. The propagation azimuths and the phase velocities of earthquake emission waves are estimated by the frequency wavenumber analysis at the frequency of 0.05Hz every 30 minutes. By subtracting the normalized azimuth distributions of the durations during -7~-3 and 3~7 from - 2~2 days to the earthquakes, directions associated with earthquake emissions can be obtained at these two arrays, respectively. The earthquake epicenter can be roughly located by the directions of these two arrays.

  16. Multiple-frequency injection-seeded nanosecond pulsed laser without parasitic intensity modulation.

    PubMed

    Penninckx, D; Luce, J; Diaz, R; Bonville, O; Courchinoux, R; Lamaignère, L

    2016-07-15

    Thanks to a phase-modulated injection seeder, we report the operation of a nanosecond Nd:YAG Q-switched laser with pulses having both a large spectral bandwidth and a smooth temporal waveform. Because of the smooth temporal waveform, such pulses allow, for instance, reducing the impact of the Kerr effect and, because of the large spectral bandwidth, suppressing stimulated Brillouin scattering. We conducted a parametric study of the features of the generated pulses versus the injection conditions. We show that, as opposed to the central frequency (wavelength) of the seeder, the phase modulation frequency has to be carefully chosen, but it is not a critical parameter and does not require any particular feedback. PMID:27420504

  17. Chronic effects of low-frequency low-intensity electrical stimulation of stretched human muscle

    NASA Astrophysics Data System (ADS)

    Shenkman, Boris S.; Lyubaeva, Ekaterina V.; Popov, Daniil V.; Netreba, Aleksey I.; Bravy, Yan R.; Tarakin, Pavel P.; Lemesheva, Yulia S.; Vinogradova, Olga L.

    2007-02-01

    Effects of low-frequency electrical stimulation, which is currently considered to be a possible countermeasure for long-duration spaceflights, with and without stretch were evaluated. Twelve young male volunteers were randomly distributed into two groups. In one group anterior thigh muscles—knee extensors of both legs were stimulated with frequency of 15 Hz for 4.5 wks, six times a week; each session was 6-h long. In the other group, electrical stimulation with the same parameters was applied to stretched knee extensors. Following stimulation the subjects exhibited an increase in fatigue resistance, and in the succinate dehydrogenase activity and a 10% gain in the percentage of muscle fibers with slow myosin heavy chain isoforms. In a stimulated group the peak voluntary strength went down significantly, the CSA of fast muscle fibers in m. quadriceps femoris became slightly less in size (10%). Electrical stimulation of the stretched muscles induced an insignificant decline in their strength and an increase of cross-sectional area of muscle fibers of both types. Thus chronic low-frequency electrical stimulation may be proposed as a candidate countermeasure against muscle strength and mass loss if it is combined with stretch.

  18. Measurement of intense coherent synchrotron radiation at frequencies around 0.1 THz using the compact S-band linac

    SciTech Connect

    Sei, Norihiro; Kuroda, Ryunosuke; Yasumoto, Masato; Toyokawa, Hiroyuki; Ogawa, Hiroshi; Koike, Masaki; Yamada, Kawakatsu

    2008-12-01

    We measured intense radiation from an electron bunch in a millimeter wave region using the compact S-band linac. The dependence of the radiation on the electron-bunch charge was measured with an rf detector system at frequencies around 0.1 THz and was confirmed to be a coherent synchrotron radiation (CSR). The total power of the horizontally and vertically polarized CSRs, which were extracted through the Z-cut quartz window within 1 ns, was calculated to be about 88 and 30 nJ/pulse, excluding the absorption by the window. The two-dimensional distribution of the vertically polarized CSR was measured at a distance of about 0.7 m from the radiation point. The CSR distribution was comparatively uniform in the horizontal plane. Intense CSR, which was reflected in the vacuum chamber, was extracted with a delay of about 6 ns. This suggests that measurement of temporal structure is needed for CSR applications.

  19. Representative electromagnetic field intensities near the Clam Lake, Wisconsin and Republic, Michigan ELF (Extremely Low Frequency) facilities

    NASA Astrophysics Data System (ADS)

    1984-01-01

    Extremely low frequency electromagnetic fields produced by ELF antennas and commercial power lines at Clam Lake, WI, and by commercial power lines at Republic, MI, have been measured at residences, businesses and forest recreational areas for the continuing assessment of the Navy's ELF Communications Program. The ELF fields from existing antennas at Clam Lake, and from power lines in both states are low. Introducing ELF antenna fields at Republic, MI in several years will not significantly change the electromagnetic environment there. The existing field intensities are interpreted and compared with independent expert, judgment, professional standards-setting and judicial and administrative law opinions regarding safe exposure of the public to ELF electromagnetic fields.

  20. Phase and intensity characterization of femtosecond pulses from a chirped-pulse amplifier by frequency-resolved optical gating

    SciTech Connect

    Kohler, B.; Yakovlev, V.V.; Wilson, K.R.; Squier, J.; DeLong, K.W.; Trebino, R.

    1995-03-01

    Frequency-resolved optical gating (FROG) measurements were made to characterize pulses from a Ti:sapphire chirped-pulse amplified laser system. By characterizing both the pulse intensity and the phase, the FROG data provided the first direct observation to our knowledge of residual phase distortion in a chirped-pulse amplifier. The FROG technique was also used to measure the regenerative amplifier dispersion and to characterize an amplitude-shaped pulse. The data provide an experimental demonstration of the value of FROG for characterizing complex pulses, including tailored femtosecond pulses for quantum control.

  1. A comparison of intense electrostatic waves near f-UHR with linear instability theory. [upper hybrid resonance frequency

    NASA Technical Reports Server (NTRS)

    Kurth, W. S.; Frank, L. A.; Gurnett, D. A.; Burek, B. J.; Ashour-Abdalla, M.; Kennel, C. F.; Sentman, D. D.

    1979-01-01

    Intense electrostatic waves near the upper hybrid resonance frequency (f-UHR) have recently been detected near but beyond the plasmapause between + or -50 deg magnetic latitude at all local times. The paper shows that the electrostatic waves observed with the ISEE 1 plasma wave receiver near f-UHR are in qualitative agreement with linear theory of multicyclotron harmonic emissions. The peak amplitudes and bandwidths observed are similar to those calculated for maximum spatial growth rates. Measurements on Hawkeye of similar waves suggest that the electric field polarization is also consistent with theory. For a wide range of plasma parameters, nonconvective instability or large spatial growth rates occur within the cyclotron band encompassing the cold upper hybrid frequency.

  2. Two-frequency acousto-optic modulator driver to improve the beam pointing stability during intensity ramps

    SciTech Connect

    Froehlich, B.; Lahaye, T.; Kaltenhaeuser, B.; Kuebler, H.; Mueller, S.; Koch, T.; Fattori, M.; Pfau, T.

    2007-04-15

    We report on a scheme to improve the pointing stability of the first order beam diffracted by an acousto-optic modulator (AOM). Due to thermal effects inside the crystal, the angular position of the beam can change by as much as 1 mrad when the radio-frequency power in the AOM is reduced to decrease the first order beam intensity. This is done, for example, to perform forced evaporative cooling in ultracold atom experiments using far-off-resonant optical traps. We solve this problem by driving the AOM with two radio frequencies f{sub 1} and f{sub 2}. The power of f{sub 2} is adjusted relative to the power of f{sub 1} to keep the total power constant. Using this, the beam displacement is decreased by a factor of 20. The method is simple to implement in existing experimental setups, without any modification of the optics.

  3. The Ex-Vivo Detection of Human Breast Cancer through High-Frequency Ultrasound

    NASA Astrophysics Data System (ADS)

    Jensen, Scott; Doyle, Timothy; Hart, Vern; Goodrich, Jeffrey; Neumayer, Leigh; Factor, Rachel

    2010-10-01

    Ex-vivo studies of human mammary surgical tissues were performed at the Huntsman Cancer Institute in order to develop an ultrasonic method to detect microscopic cancer in surgical margins during breast conservation surgery. Both pitch-catch and pulse-echo measurements were acquired using a high-frequency ultrasound system operating at 50 MHz. The ultrasonic tissue signatures were categorized into three groups: Malignant tumors, fibroadenomas, and normal tissues. An analysis in the frequency domain was performed to detect frequency dependencies and unique signatures for each of these groups. Signatures were then used in a final analysis to determine future possibilities in systematic cancer detection using this approach. Results of this study and spectral comparisons are reported.

  4. Intensity-modulated radiation therapy, protons, and the risk of second cancers

    SciTech Connect

    Hall, Eric J. . E-mail: ejh1@columbia.edu

    2006-05-01

    Intensity-modulated radiation therapy (IMRT) allows dose to be concentrated in the tumor volume while sparing normal tissues. However, the downside to IMRT is the potential to increase the number of radiation-induced second cancers. The reasons for this potential are more monitor units and, therefore, a larger total-body dose because of leakage radiation and, because IMRT involves more fields, a bigger volume of normal tissue is exposed to lower radiation doses. Intensity-modulated radiation therapy may double the incidence of solid cancers in long-term survivors. This outcome may be acceptable in older patients if balanced by an improvement in local tumor control and reduced acute toxicity. On the other hand, the incidence of second cancers is much higher in children, so that doubling it may not be acceptable. IMRT represents a special case for children for three reasons. First, children are more sensitive to radiation-induced cancer than are adults. Second, radiation scattered from the treatment volume is more important in the small body of the child. Third, the question of genetic susceptibility arises because many childhood cancers involve a germline mutation. The levels of leakage radiation in current Linacs are not inevitable. Leakage can be reduced but at substantial cost. An alternative strategy is to replace X-rays with protons. However, this change is only an advantage if the proton machine employs a pencil scanning beam. Many proton facilities use passive modulation to produce a field of sufficient size, but the use of a scattering foil produces neutrons, which results in an effective dose to the patient higher than that characteristic of IMRT. The benefit of protons is only achieved if a scanning beam is used in which the doses are 10 times lower than with IMRT.

  5. A meta-analysis of MSI frequency and race in colorectal cancer

    PubMed Central

    Ashktorab, Hassan; Ahuja, Sadhna; Kannan, Lakshmi; Llor, Xavier; Ellis, Nathan A.; Xicola, Rosa M.; Laiyemo, Adeyinka O.; Carethers, John M.; Brim, Hassan; Nouraie, Mehdi

    2016-01-01

    PURPOSE African Americans (AA) are at a higher risk of colorectal cancer (CRC) and some studies report a higher frequency of microsatellite instability (MSI) in this population while others report lower frequency compared to Caucasians. AIM To determine and evaluate the association of race and clinical factors with MSI frequency through meta- analysis. METHODS Twenty-two studies out of 15,105 (1997-2015) were evaluated after a search in different literature databases, using keywords “colorectal cancer, microsatellite instability, African Americans, Caucasians and Hispanics”. We used random effect meta-analysis to calculate the MSI frequency in all studies as well as in African American and Caucasian samples. Meta-regression analysis was used to assess the univariate effect of race, gender, age, tumor location and stage on MSI frequency. RESULTS The overall MSI frequency among CRCs was 17% (95%CI: 15%-19%, I²=91%). In studies with available race data, The MSI rate among AAs, Hispanics and Caucasians were 12%, 12% and 14% respectively and was not significantly different. Sub-group analysis of studies with racial information indicates MSI OR of 0.78 for AAs compared to Caucasians. CONCLUSION CRCs demonstrate an overall MSI frequency of 17%. MSI frequency differences between AAs and Caucasians were not pronounced, suggesting that other factors contribute to the racial disparity. The methodological approaches and biological sources of the variation seen in MSI frequency between different studies need to be further investigated. PMID:27120810

  6. Effects of Extratropical Cyclone Frequency and Intensity on mass balance of the Greenland Ice Sheet

    NASA Astrophysics Data System (ADS)

    Auger, J.; Birkel, S. D.; Maasch, K. A.; Mayewski, P. A.

    2014-12-01

    Significant Arctic-wide warming over the past decade is thought to result in part from a weakening of the equator-pole thermal gradient in the atmosphere. Francis and Vavrus (2012) and others link Arctic amplification, or enhanced Arctic warming, to decreasing extratropical cyclone (ETC) speeds, and increasing northward meridional heat transports. Here, we are using the latest high-resolution reanalysis models (ASR, JRA-55, CFSR, ERA-Interim, MERRA) to evaluate how Arctic amplification may be impacting the mass balance of the Greenland Ice Sheet. Our approach is to assess synoptic-scale changes in circulation as represented by changes in storm tracks and storm intensities in the North Atlantic region. As part of this work, we are validating the reanalysis models against existing accumulation, ablation, and meteorological station data available across Greenland, and therefore hope to gain insights on model performance and applicability to the problem domain.

  7. Infrared frequencies and intensities for astrophysically important polycyclic aromatic hydrocarbon cations

    NASA Technical Reports Server (NTRS)

    Szczepanski, Jan; Vala, Martin

    1993-01-01

    Polycyclic aromatic hydrocarbons (PAHs) have been implicated as the carriers of the 'unidentified infrared' (UIR) emission bands observed from the interstellar medium. It has long been thought that these molecules, if present, probably exist as cations. In this paper we present infrared spectra of the cations of five moderate-sized PAHs. The PAH cations have been produced by low-energy electron impact and then trapped and stabilized in argon matrices at 12 K. To date, results have been obtained on naphthalene, anthracene, pyrene, perylene, and coronene. A common feature of the infrared spectra of all these cations is the very different intensity pattern of the ions compared to the neutral parents. Visible and (partial) infrared spectra of the coronene cation are also presented. It is shown that the out-of-plane CH bending mode shifts to a position very close to the UIR band at 11.3 microns. The astrophysical impact of these observations is discussed.

  8. Proton therapy versus intensity modulated x-ray therapy in the treatment of prostate cancer: Estimating secondary cancer risks

    NASA Astrophysics Data System (ADS)

    Fontenot, Jonas David

    External beam radiation therapy is used to treat nearly half of the more than 200,000 new cases of prostate cancer diagnosed in the United States each year. During a radiation therapy treatment, healthy tissues in the path of the therapeutic beam are exposed to high doses. In addition, the whole body is exposed to a low-dose bath of unwanted scatter radiation from the pelvis and leakage radiation from the treatment unit. As a result, survivors of radiation therapy for prostate cancer face an elevated risk of developing a radiogenic second cancer. Recently, proton therapy has been shown to reduce the dose delivered by the therapeutic beam to normal tissues during treatment compared to intensity modulated x-ray therapy (IMXT, the current standard of care). However, the magnitude of stray radiation doses from proton therapy, and their impact on this incidence of radiogenic second cancers, was not known. The risk of a radiogenic second cancer following proton therapy for prostate cancer relative to IMXT was determined for 3 patients of large, median, and small anatomical stature. Doses delivered to healthy tissues from the therapeutic beam were obtained from treatment planning system calculations. Stray doses from IMXT were taken from the literature, while stray doses from proton therapy were simulated using a Monte Carlo model of a passive scattering treatment unit and an anthropomorphic phantom. Baseline risk models were taken from the Biological Effects of Ionizing Radiation VII report. A sensitivity analysis was conducted to characterize the uncertainty of risk calculations to uncertainties in the risk model, the relative biological effectiveness (RBE) of neutrons for carcinogenesis, and inter-patient anatomical variations. The risk projections revealed that proton therapy carries a lower risk for radiogenic second cancer incidence following prostate irradiation compared to IMXT. The sensitivity analysis revealed that the results of the risk analysis depended only

  9. Expert Consensus Contouring Guidelines for Intensity Modulated Radiation Therapy in Esophageal and Gastroesophageal Junction Cancer

    SciTech Connect

    Wu, Abraham J.; Bosch, Walter R.; Chang, Daniel T.; Hong, Theodore S.; Jabbour, Salma K.; Kleinberg, Lawrence R.; Mamon, Harvey J.; Thomas, Charles R.; Goodman, Karyn A.

    2015-07-15

    Purpose/Objective(s): Current guidelines for esophageal cancer contouring are derived from traditional 2-dimensional fields based on bony landmarks, and they do not provide sufficient anatomic detail to ensure consistent contouring for more conformal radiation therapy techniques such as intensity modulated radiation therapy (IMRT). Therefore, we convened an expert panel with the specific aim to derive contouring guidelines and generate an atlas for the clinical target volume (CTV) in esophageal or gastroesophageal junction (GEJ) cancer. Methods and Materials: Eight expert academically based gastrointestinal radiation oncologists participated. Three sample cases were chosen: a GEJ cancer, a distal esophageal cancer, and a mid-upper esophageal cancer. Uniform computed tomographic (CT) simulation datasets and accompanying diagnostic positron emission tomographic/CT images were distributed to each expert, and the expert was instructed to generate gross tumor volume (GTV) and CTV contours for each case. All contours were aggregated and subjected to quantitative analysis to assess the degree of concordance between experts and to generate draft consensus contours. The panel then refined these contours to generate the contouring atlas. Results: The κ statistics indicated substantial agreement between panelists for each of the 3 test cases. A consensus CTV atlas was generated for the 3 test cases, each representing common anatomic presentations of esophageal cancer. The panel agreed on guidelines and principles to facilitate the generalizability of the atlas to individual cases. Conclusions: This expert panel successfully reached agreement on contouring guidelines for esophageal and GEJ IMRT and generated a reference CTV atlas. This atlas will serve as a reference for IMRT contours for clinical practice and prospective trial design. Subsequent patterns of failure analyses of clinical datasets using these guidelines may require modification in the future.

  10. Phytoplankton dynamics and blooms: study of the spectral dynamics and extreme intensities using high frequency data

    NASA Astrophysics Data System (ADS)

    Derot, J.; Schmitt, F. G.; Gentilhomme, V.; Zongo, S.

    2012-12-01

    We consider in this study the fluorescence time series from an automatic measuring buoy in the Eastern English Channel (Boulogne-sur-mer, France). The data are recorded at an automatic station equipped with physic-chemical measuring devices with time resolution of 20 minutes. The fluorescence data are measured from 2004 to present and the fluorescence sensor covers measurement from 0 up to 50 FFU. The fluorescence data from 2004 to 2012 reveal very large fluctuations at all scales showing the different intensities that are often associated with phytoplankton blooms. We consider the dynamics by studying the Fourier power-law regimes and also by using empirical mode decomposition of the time series. In order to consider the extremes, we estimate the probability density function of fluorescence and characterize its extremes by comparing lognormal and power law fits. We finally perform year-by-year analyses of the dynamics and extreme statistics, in order to obtain universal behaviour in relation with mean annual abundance.

  11. Frequency and outcome of patients with nonthyroidal illness syndrome in a medical intensive care unit.

    PubMed

    Plikat, Katharina; Langgartner, Julia; Buettner, Roland; Bollheimer, L Cornelius; Woenckhaus, Ulrike; Schölmerich, Jürgen; Wrede, Christian E

    2007-02-01

    Acute and chronic critical conditions are associated with reduced serum levels of free triiodothyronine (FT(3)), free thyroxine FT(4), and thyrotropin, known as nonthyroidal illness syndrome (NTIS). It is still controversial whether these changes reflect a protective mechanism or a maladaptive process during prolonged illness. However, larger studies to determine the prevalence of the NTIS and its association with outcome in medical intensive care units (ICUs) are missing. Complete thyroid hormone levels from 247 of 743 patients admitted to our ICU between October 2002 and February 2004 were retrospectively evaluated. From these patients, Acute Physiology and Chronic Health II scores, ICU mortality, length of stay, mechanical ventilation, and concomitant medication were recorded. Ninety-seven patients (44.1%) had low FT(3) levels indicating an NTIS, either with normal (23.6%) or reduced (20.5%) serum thyrotropin levels. Of 97 patients with NTIS, 24 (23.3%) also showed reduced serum FT(4) levels. The NTIS was significantly associated with Acute Physiology and Chronic Health II scores, mortality, length of stay, and mechanical ventilation. In a multivariate Cox regression analysis, the combination of low FT(3) and low FT(4) was an independent risk factor for survival. Nonthyroidal illness syndrome is frequent at a medical ICU. A reduction of FT(4) together with FT(3) is associated with an increase in mortality and might reflect a maladaptive process, thereby worsening the disease.

  12. Statistical Modeling of Effects of ENSO on the Intensity, Duration and Frequency of Hot Spells in India

    NASA Astrophysics Data System (ADS)

    Mondal, A.; Mujumdar, P.

    2013-12-01

    Global climate change is expected to intensify climate and weather extremes which can cause significant societal impacts through interactions with existing human and natural systems. A comprehensive statistical study of such extreme events is thus necessary; at the same time, such a study is challenging since extreme events are rare by definition. The theoretical foundation of the statistical extreme value theory (EVT) and the recent advances in it that allow incorporating temporal trends in modelling the extreme values have rarely been explored for modelling hot spells and heat waves. Hot spells and heat waves are particularly significant for a warm country like India, and natural climate variability modes like the ENSO are reported to be associated with extreme temperature indices in the Indian region. We attempt to model the non-stationary effects of ENSO on the intensity, duration and frequency of hot spells in the summer season, at 1 degree x 1 degree lat-lon grids over India. In the threshold exceedence model that we employ, the intensity and frequency of hot spells are modeled by a Poisson-Generalized Pareto (Poisson-GP) model, and the spell lengths are modeled by a Geometric distribution. Average sea surface temperature (SST) anomaly time series over the NINO3.4 region, which is the ENSO index here, and annual cycles in time are considered as covariates in each of the distributions. Hot spells are defined as the time period when the daily maximum temperature is above a chosen threshold, and they are separated by at least one day when the daily maximum temperature falls below the threshold. The occurrence of hot spells is assumed to be a Poisson process and the maximum of each hot spell is taken as the intensity, which is modeled by the Generalized Pareto (GP) distribution. Trends in the Poisson and Geometric distributions are introduced through a generalized linear model (GLM) framework. Significance of trends in the parameters of the distributions due to

  13. Relationship between spontaneous frequency of aneuploidy and cancer risk in 2145 healthy Hungarian subjects.

    PubMed

    Farkas, Gyöngyi; Jurányi, Zsolt; Székely, Gábor; Kocsis, Zsuzsa S; Gundy, Sarolta

    2016-09-01

    Numerical and structural chromosomal abnormalities are the hallmarks of cancer. Whereas the structural chromosome aberrations got more substantial attention for cancer risk assessment in a healthy population, the role of aneuploidy is much less understood in this respect. We analysed the frequency of numerical (and structural) aberrations in peripheral blood lymphocytes of 2145 healthy individuals between 1989 and 2010, taking into account different biological- and exposure-conditions. We also studied to what extent chromosome gains or losses may predict the probability of cancer. The average frequency of all aneuploid cells was 1.78±0.06% in the entire study population, which increased linearly with age. Gender and smoking did not influence the values, however, occupational exposures did. The highest frequency of aneuploidy was found in chemical industry-workers (1.89±0.05%) compared with the lowest value of medical radiation workers (1.44±0.10%), respectively. No correlation was found between numerical and structural chromosomal aberrations. Cancer incidence followed for 1-23 years after the chromosome analysis showed a 1.26-fold relative risk (confidence interval: 1.02-1.58; P = 0.04) for those with higher frequency of aneuploid cells (1.82% vs. 1.44% in controls). Hypodiploidy had higher impact on the cancer risk than hyperdiploidy (1.72% vs. 0.10%). Our findings on the frequency of numerical aberrations in a healthy cohort represent the largest cytogenetic database from one laboratory with an unchanged mechanistic scoring method during a 30-year period, and provide basic information not only for genotoxicological studies but also confirm the association between numerical aberrations and cancer risk. PMID:27245077

  14. Low-frequency acoustic pressure, velocity, and intensity thresholds in a bottlenose dolphin (Tursiops truncatus) and white whale (Delphinapterus leucas)

    NASA Astrophysics Data System (ADS)

    Finneran, James J.; Carder, Donald A.; Ridgway, Sam H.

    2002-01-01

    The relative contributions of acoustic pressure and particle velocity to the low-frequency, underwater hearing abilities of the bottlenose dolphin (Tursiops truncatus) and white whale (Delphinapterus leucas) were investigated by measuring (masked) hearing thresholds while manipulating the relationship between the pressure and velocity. This was accomplished by varying the distance within the near field of a single underwater sound projector (experiment I) and using two underwater sound projectors and an active sound control system (experiment II). The results of experiment I showed no significant change in pressure thresholds as the distance between the subject and the sound source was changed. In contrast, velocity thresholds tended to increase and intensity thresholds tended to decrease as the source distance decreased. These data suggest that acoustic pressure is a better indicator of threshold, compared to particle velocity or mean active intensity, in the subjects tested. Interpretation of the results of experiment II (the active sound control system) was difficult because of complex acoustic conditions and the unknown effects of the subject on the generated acoustic field; however, these data also tend to support the results of experiment I and suggest that odontocete thresholds should be reported in units of acoustic pressure, rather than intensity.

  15. Substantial fluctuation of acoustic intensity transmittance through a bone-phantom plate and its equalization by modulation of ultrasound frequency.

    PubMed

    Saito, Osamu; Wang, Zuojun; Mitsumura, Hidetaka; Ogawa, Takeki; Iguchi, Yasuyuki; Yokoyama, Masayuki

    2015-05-01

    For safe and efficient sonothrombolysis therapies, accurate estimation of ultrasound transmittance through the human skull is essential. The present study clarifies uncertainty surrounding this transmittance and experimentally verifies the equalization of transmittance through the modulation of ultrasound frequency. By changing three factors (ultrasound frequency, the thickness of a bone-phantom plate, and the distance between a transducer and a bone-phantom plate), we measured the intensity of ultrasound passing through the plate. Two activating methods, sinusoidal waves at 500 kHz and modulated waves, were compared. When we changed (1) the distance between a transducer and a bone-phantom plate and (2) the thickness of the bone-phantom plate, ultrasound transmittance through the plates substantially fluctuated. The substantial fluctuation in transmittance was observed also for a cut piece of human temporal skull bone. This fluctuation significantly declined for the modulated wave. In conclusion, modulation of ultrasound frequency can equalize the transmittance with an approximately 30-65% fluctuation drop and an approximately 40% fluctuation drop for a bone-phantom plate and for a cut piece of skull bone, respectively. By using modulated waves, we can develop safer and more effective sonothrombolysis therapies.

  16. Barrett's oesophagus: frequency and prediction of dysplasia and cancer.

    PubMed

    Falk, Gary W

    2015-02-01

    The incidence of oesophageal adenocarcinoma is continuing to increase at an alarming rate in the Western world today. Barrett's oesophagus is a clearly recognized risk factor for the development of oesophageal adenocarcinoma, but the overwhelming majority of patients with Barrett's oesophagus will never develop oesophageal cancer. A number of endoscopic, histologic and epidemiologic risk factors identify Barrett's oesophagus patients at increased risk for progression to high-grade dysplasia and oesophageal adenocarcinoma. Endoscopic factors include segment length, mucosal abnormalities as seemingly trivial as oesophagitis and the 12 to 6 o'clock hemisphere of the oesophagus. Both intestinal metaplasia and low grade dysplasia, the latter only if confirmed by a pathologist with expertise in Barrett's oesophagus pathologic interpretation are the histologic risk factors for progression. Epidemiologic risk factors include ageing, male gender, obesity, and smoking. Factors that may protect against the development of adenocarcinoma include a diet rich in fruits and vegetables, and the use of proton pump inhibitors, aspirin/NSAIDs and statins. PMID:25743461

  17. Barrett's oesophagus: frequency and prediction of dysplasia and cancer.

    PubMed

    Falk, Gary W

    2015-02-01

    The incidence of oesophageal adenocarcinoma is continuing to increase at an alarming rate in the Western world today. Barrett's oesophagus is a clearly recognized risk factor for the development of oesophageal adenocarcinoma, but the overwhelming majority of patients with Barrett's oesophagus will never develop oesophageal cancer. A number of endoscopic, histologic and epidemiologic risk factors identify Barrett's oesophagus patients at increased risk for progression to high-grade dysplasia and oesophageal adenocarcinoma. Endoscopic factors include segment length, mucosal abnormalities as seemingly trivial as oesophagitis and the 12 to 6 o'clock hemisphere of the oesophagus. Both intestinal metaplasia and low grade dysplasia, the latter only if confirmed by a pathologist with expertise in Barrett's oesophagus pathologic interpretation are the histologic risk factors for progression. Epidemiologic risk factors include ageing, male gender, obesity, and smoking. Factors that may protect against the development of adenocarcinoma include a diet rich in fruits and vegetables, and the use of proton pump inhibitors, aspirin/NSAIDs and statins.

  18. The changes of the frequency specific impedance of the human body due to the resonance in the kHz range in cancer diagnostics

    NASA Astrophysics Data System (ADS)

    Michalak, K. P.; Nawrocka-Bogusz, H.

    2011-12-01

    The frequency-specific absorption of kHz signals has been postulated for different tissues, trace elements, vitamins, toxins, pathogens, allergens etc. for low-power (μV) signals. An increase in the impedance of the human body is observed only up to the given power of the applied signal. The highest amplification of the given signal being damped by the body makes it possible to determine the intensity of the given process in the body (e.g. amount of the toxin, trace element, intensity of the allergy) being connected with a given frequency spectrum of the signal. The mechanism of frequency-specific absorption can be explained by means of the Quantum Field Theory being applied to the structure of the water. Substantially high coincidence between the frequencies of the rotation of free quasi-excited electrons in coherent domains of water and the frequencies being used in the MORA diagnostics (Med-Tronic GmbH, EN ISO 13485, EN ISO 9001) can be observed. These frequencies are located in the proximity of f = 7kHz · i (i = 1,3,5,7,...). This fact suggests that the coherent domains with the admixtures of the given substances create structure-specific coherent domains that possess frequency-specific absorption spectra. The diagnostic tool called "MORA System diagnosis" was used to investigate 102 patients with different types and stages of cancer. Many signals were observed to be absorbed by many cancer patients, e.g.: 'Cellular defense system', 'Degeneration tendencies', Manganese, Magnesium, Zinc, Selenium, Vitamin E, Glutamine, Glutathione, Cysteine, Candida albicans, Mycosis. The results confirm the role of oxidative stress, immunological system deficiency and mitochondria malfunction in the development of cancer.

  19. The inaugural Frank Ellis Lecture--latrogenic cancer: the impact of intensity-modulated radiotherapy.

    PubMed

    Hall, E J

    2006-05-01

    It is an honour and personal pleasure to give the inaugural Frank Ellis Lecture to celebrate his 100th birthday, and to acknowledge his enormous contributions to radiation oncology. Intensity-modulated radiotherapy (IMRT) allows dose to be concentrated in the tumour volume while sparing normal tissues. However, the downside to IMRT is the potential to increase the number of radiation-induced second cancers because more fields are used which involves a bigger volume of normal tissue exposed to lower doses. It has been estimated that IMRT may double the incidence of solid cancers in long-term survivors. This may be acceptable in older patients if balanced by an improvement in local tumour control and reduced toxicity. On the other hand, the incidence of second cancers is higher in children, so that doubling it may not be acceptable. IMRT represents a special case for children. First, they are more sensitive to radiation-induced cancer than adults. Second, radiation scattered from the treatment volume is more important in the small body of the child. Third, there is the question of genetic susceptibility, as many childhood cancers involve a germline mutation. The levels of leakage radiation in current Linacs can be reduced, but the cost would be substantial. An alternative strategy is to replace X-rays with protons. This is an advantage only if the proton machine uses a pencil scanning beam, as passive modulation of a scattering foil produces neutrons, which results in an effective dose to the patient higher than that characteristic of IMRT.

  20. Low-Frequency Low-Intensity Ultrasounds Do Not Influence the Survival and Immune Functions of Cultured Keratinocytes and Dendritic Cells

    PubMed Central

    Scarponi, Claudia; Nasorri, Francesca; Pavani, Francesca; Madonna, Stefania; Sestito, Rosanna; Simonacci, Marco; De Pità, Ornella; Cavani, Andrea; Albanesi, Cristina

    2009-01-01

    Low-frequency ultrasounds (US) are used to enhance drug transdermal transport. Although this phenomenon has been extensively analyzed, information on US effects on the single skin cell components is limited. Here, we investigated the possible effects of low-frequency US on viability and immune functions of cultured human keratinocytes and dendritic cells (DC), skin cells involved in the regulation of many immune-mediated dermatoses. We demonstrated that US, employed at low-frequency (42 KHz) and low-intensity (0.15 W/cm2) values known to enhance drug and water transdermal transport, did not affect extracellular-signal-regulated-kinase (ERK)1/2 activation, cell viability, or expression of adhesion molecules in cultured keratinocytes. Moreover, US at these work frequency and intensity did not influence the keratinocyte expression and release of immunomodulatory molecules. Similarly, cultured DC treated with low-frequency low-intensity US were viable, and did not show an altered membrane phenotype, cytokine profile, nor antigen presentation ability. However, intensity enhancement of low-frequency US to 5 W/cm2 determined an increase of the apoptotic rate of both keratinocytes and DC as well as keratinocyte CXCL8 release and ERK1/2 activation, and DC CD40 expression. Our study sustains the employment of low-frequency and low-intensity US for treatment of those immune skin disorders, where keratinocytes and DC have a pathogenetic role. PMID:20145702

  1. Effect of Intensity-Modulated Pelvic Radiotherapy on Second Cancer Risk in the Postoperative Treatment of Endometrial and Cervical Cancer

    SciTech Connect

    Zwahlen, Daniel R. Ruben, Jeremy D.; Jones, Phillip; Gagliardi, Frank; Millar, Jeremy L.; Schneider, Uwe

    2009-06-01

    Purpose: To estimate and compare intensity-modulated radiotherapy (IMRT) with three-dimensional conformal radiotherapy (3DCRT) in terms of second cancer risk (SCR) for postoperative treatment of endometrial and cervical cancer. Methods and Materials: To estimate SCR, the organ equivalent dose concept with a linear-exponential, a plateau, and a linear dose-response model was applied to dose distributions, calculated in a planning computed tomography scan of a 68-year-old woman. Three plans were computed: four-field 18-MV 3DCRT and nine-field IMRT with 6- and 18-MV photons. SCR was estimated as a function of target dose (50.4 Gy/28 fractions) in organs of interest according to the International Commission on Radiological Protection Results: Cumulative SCR relative to 3DCRT was +6% (3% for a plateau model, -4% for a linear model) for 6-MV IMRT and +26% (25%, 4%) for the 18-MV IMRT plan. For an organ within the primary beam, SCR was +12% (0%, -12%) for 6-MV and +5% (-2%, -7%) for 18-MV IMRT. 18-MV IMRT increased SCR 6-7 times for organs away from the primary beam relative to 3DCRT and 6-MV IMRT. Skin SCR increased by 22-37% for 6-MV and 50-69% for 18-MV IMRT inasmuch as a larger volume of skin was exposed. Conclusion: Cancer risk after IMRT for cervical and endometrial cancer is dependent on treatment energy. 6-MV pelvic IMRT represents a safe alternative with respect to SCR relative to 3DCRT, independently of the dose-response model. 18-MV IMRT produces second neutrons that modestly increase the SCR.

  2. Intensity-Modulated Radiotherapy for Sinonasal Cancer: Improved Outcome Compared to Conventional Radiotherapy

    SciTech Connect

    Dirix, Piet; Vanstraelen, Bianca; Jorissen, Mark; Vander Poorten, Vincent; Nuyts, Sandra

    2010-11-15

    Purpose: To evaluate clinical outcome and toxicity of postoperative intensity-modulated radiotherapy (IMRT) for malignancies of the nasal cavity and paranasal sinuses. Methods and Materials: Between 2003 and 2008, 40 patients with cancer of the paranasal sinuses (n = 34) or nasal cavity (n = 6) received postoperative IMRT to a dose of 60 Gy (n = 21) or 66 Gy (n = 19). Treatment outcome and toxicity were retrospectively compared with that of a previous patient group (n = 41) who were also postoperatively treated to the same doses but with three-dimensional conformal radiotherapy without intensity modulation, from 1992 to 2002. Results: Median follow-up was 30 months (range, 4-74 months). Two-year local control, overall survival, and disease-free survival were 76%, 89%, and 72%, respectively. Compared to the three-dimensional conformal radiotherapy treatment, IMRT resulted in significantly improved disease-free survival (60% vs. 72%; p = 0.02). No grade 3 or 4 toxicity was reported in the IMRT group, either acute or chronic. The use of IMRT significantly reduced the incidence of acute as well as late side effects, especially regarding skin toxicity, mucositis, xerostomia, and dry-eye syndrome. Conclusions: Postoperative IMRT for sinonasal cancer significantly improves disease-free survival and reduces acute as well as late toxicity. Consequently, IMRT should be considered the standard treatment modality for malignancies of the nasal cavity and paranasal sinuses.

  3. High Frequency Migraine Is Associated with Lower Acute Pain Sensitivity and Abnormal Insula Activity Related to Migraine Pain Intensity, Attack Frequency, and Pain Catastrophizing

    PubMed Central

    Mathur, Vani A.; Moayedi, Massieh; Keaser, Michael L.; Khan, Shariq A.; Hubbard, Catherine S.; Goyal, Madhav; Seminowicz, David A.

    2016-01-01

    Migraine is a pain disorder associated with abnormal brain structure and function, yet the effect of migraine on acute pain processing remains unclear. It also remains unclear whether altered pain-related brain responses and related structural changes are associated with clinical migraine characteristics. Using fMRI and three levels of thermal stimuli (non-painful, mildly painful, and moderately painful), we compared whole-brain activity between 14 migraine patients and 14 matched controls. Although, there were no significant differences in pain thresholds nor in pre-scan pain ratings to mildly painful thermal stimuli, patients did have aberrant suprathreshold nociceptive processing. Brain imaging showed that, compared to controls, patients had reduced activity in pain modulatory regions including left dorsolateral prefrontal, posterior parietal, and middle temporal cortices and, at a lower-threshold, greater activation in the right mid-insula to moderate pain vs. mild pain. We also found that pain-related activity in the insula was associated with clinical variables in patients, including associations between: bilateral anterior insula and pain catastrophizing (PCS); bilateral anterior insula and contralateral posterior insula and migraine pain intensity; and bilateral posterior insula and migraine frequency at a lower-threshold. PCS and migraine pain intensity were also negatively associated with activity in midline regions including posterior cingulate and medial prefrontal cortices. Diffusion tensor imaging revealed a negative correlation between fractional anisotropy (a measure of white matter integrity; FA) and migraine duration in the right mid-insula and a positive correlation between left mid-insula FA and PCS. In sum, while patients showed lower sensitivity to acute noxious stimuli, the neuroimaging findings suggest enhanced nociceptive processing and significantly disrupted modulatory networks, particularly involving the insula, associated with indices

  4. Intensive terahertz emission from GaSe0.91S0.09 under collinear difference frequency generation

    NASA Astrophysics Data System (ADS)

    Huang, Jingguo; Huang, Zhiming; Tong, Jingchao; Ouyang, Cheng; Chu, Junhao; Andreev, Yury; Kokh, Konstantin; Lanskii, Grigory; Shaiduko, Anna

    2013-08-01

    An intensive, broad tunable monochromatic Terahertz (THz) emission is generated from S-doped (2 wt. %) GaSe (solid solution GaSe0.91S0.09) crystals by collinear difference frequency generation method. The generated THz signal of 3.8 ns covers the spectral range of 0.57-3.57 THz (84.0-528.0 μm), with a maximal THz output peak power of 21.8 W at 1.62 THz. The THz power conversion efficiency is of 45% higher than that of undoped GaSe, which is mainly contributed to the improved optical properties. The terahertz source is of great potential to be exploited for the out-of-door applications due to the increased crystal hardness.

  5. Age-related prevalence, intensity and frequency distribution of gastrointestinal helminth infection in urban slum children from Kuala Lumpur, Malaysia.

    PubMed

    Bundy, D A; Kan, S P; Rose, R

    1988-01-01

    The gastrointestinal helminth infection status of 1574 children living in a slum area of Kuala Lumpur, Malaysia was assessed by quantitative coprology. Almost two-thirds were infected with Trichuris trichiura, 49.6% with Ascaris lumbricoides, and 5.3% with hookworm. Infection prevalence rose rapidly to a stable asymptote at 7 years of age, and the age-intensity profile was convex with maximal values in the 5-10 year age classes. This pattern was the same for males and females, but differed markedly between different ethnic groups. The frequency distributions of A. lumbricoides and T. trichiura were highly overdispersed (k values were 0.21 and 0.27, respectively), and age-dependent over the 0-8 year age classes. This suggests that the force of infection with these nematodes is lower in infants than in older children.

  6. Intensity-modulated linear-frequency-modulated continuous-wave lidar for distributed media: fundamentals of technique.

    PubMed

    Batet, Oscar; Dios, Federico; Comeron, Adolfo; Agishev, Ravil

    2010-06-10

    We analyze the intensity-modulation frequency-modulated continuous-wave (FMCW) technique for lidar remote sensing in the context of its application to distributed media. The goal of the technique is the reproduction of the sounded-medium profile along the emission path. A conceptual analysis is carried out to show the problems the basic version of the method presents for this application. The principal point is the appearance of a bandpass filtering effect, which seems to hinder its use in this context. A modified version of the technique is proposed to overcome this problem. A number of computer simulations confirm the ability of the modified FMCW technique to sound distributed media. PMID:20539357

  7. Sunflower exposed to high-intensity microwave-frequency electromagnetic field: electrophysiological response requires a mechanical injury to initiate.

    PubMed

    Roux, David; Catrain, Alexandre; Lallechere, Sébastien; Joly, Jean-Christophe

    2015-01-01

    We have monitored the electrical potential variations (EPV) of sunflower plants illuminated by a high-intensity microwave-frequency (2.5 GHz, 1.5 kV/m) electromagnetic field (EMF). We have designed an appropriate set-up that allows parallel temperature and EPV measurements while part of the plant is being exposed to the field. The results show that the considered EMF does not induce plant EPV directly. This electrophysiological response appears only when the EMF leads to a mechanical injury of the tissues via a thermal effect (dielectric heating). Once the plant inner temperature reached a threshold, we systematically observed burn-like lesions associated with the bending of the stem or leaf-stalks. Theses mechanical constraints were rapidly followed by EPVs, moving through the stem.

  8. Risk of secondary cancers from scattered radiation during intensity-modulated radiotherapies for hepatocellular carcinoma

    PubMed Central

    2014-01-01

    Purpose To evaluate and compare the risks of secondary cancers from therapeutic doses received by patients with hepatocellular carcinoma (HCC) during intensity-modulated radiotherapy (IMRT), volumetric arc therapy (VMAT), and tomotherapy (TOMO). Methods Treatments for five patients with hepatocellular carcinoma (HCC) were planned using IMRT, VMAT, and TOMO. Based on the Biological Effects of Ionizing Radiation VII method, the excess relative risk (ERR), excess absolute risk (EAR), and lifetime attributable risk (LAR) were evaluated from therapeutic doses, which were measured using radiophotoluminescence glass dosimeters (RPLGDs) for each organ inside a humanoid phantom. Results The average organ equivalent doses (OEDs) of 5 patients were measured as 0.23, 1.18, 0.91, 0.95, 0.97, 0.24, and 0.20 Gy for the thyroid, lung, stomach, liver, small intestine, prostate (or ovary), and rectum, respectively. From the OED measurements, LAR incidence were calculated as 83, 46, 22, 30, 2 and 6 per 104 person for the lung, stomach, normal liver, small intestine, prostate (or ovary), and rectum. Conclusions We estimated the secondary cancer risks at various organs for patients with HCC who received different treatment modalities. We found that HCC treatment is associated with a high secondary cancer risk in the lung and stomach. PMID:24886163

  9. Changes in circulating immunosuppressive cytokine levels of cancer patients after high intensity focused ultrasound treatment.

    PubMed

    Zhou, Qiang; Zhu, Xue-Qiang; Zhang, Jun; Xu, Zhong-Lin; Lu, Pei; Wu, Feng

    2008-01-01

    Immunosuppression in a patient with malignant tumor is a major obstacle in cancer treatment. In this study, we investigated changes in the circulating level of all measured immunosuppressive cytokines in patients with malignancy before and after high intensity focused ultrasound (HIFU) treatment. Fifteen patients with solid malignancy were enrolled in this study and an enzyme-linked immunoabsorbent assay (ELISA) method was used to measure serum level of vascular endothelial growth factor (VEGF), transforming growth factor-beta1 (TGF-beta1), transforming growth factor-beta2 (TGF-beta2), interleukin 6 (IL-6) and interleukin 10 (IL-10), respectively before and 1 wk after HIFU treatment. Among them, seven patients had distant metastasis and the remaining eight had no metastasis. All patients received one-session HIFU treatment for primary cancer, including complete ablation in eight patients without metastasis, and partial ablation in seven patients with metastases. The results showed that serum immunosuppressive cytokine levels decreased after HIFU treatment, and there were significant decreases of VEGF, TGF-beta1, and TGF-beta2 before and after HIFU treatment. Compared with the values in the metastatic patients, serum levels of immunosuppressive cytokines were significantly lower in the nonmetastatic patients after HIFU treatment. It is concluded that HIFU can decrease tumor-secreted immunosuppressive cytokine production in addition to its direct tumor destruction. This change may lessen tumor-induced immunosuppression and renew antitumor immunity after HIFU in cancer patients.

  10. Effect of frequency tuning on bremsstrahlung spectra, beam intensity, and shape in the 10 GHz NANOGAN electron cyclotron resonance ion source

    SciTech Connect

    Rodrigues, G. Mal, Kedar; Kumar, Narender; Lakshmy, P. S.; Mathur, Y.; Kumar, P.; Kanjilal, D.; Roy, A.; Baskaran, R.

    2014-02-15

    Studies on the effect of the frequency tuning on the bremsstrahlung spectra, beam intensities, and beam shape of various ions have been carried out in the 10 GHz NANOGAN ECR ion source. The warm and cold components of the electrons were found to be directly correlated with beam intensity enhancement in case of Ar{sup 9+} but not so for O{sup 5+}. The warm electron component was, however, much smaller compared to the cold component. The effect of the fine tuning of the frequency on the bremsstrahlung spectrum, beam intensities and beam shape is presented.

  11. Frequency of virulence genes of Escherichia coli among newborn piglets from an intensive pig farm in Argentina.

    PubMed

    Alustiza, Fabrisio E; Picco, Natalia Y; Bellingeri, Romina V; Terzolo, Horacio R; Vivas, Adriana B

    2012-01-01

    The enterotoxigenic and porcine enteropathogenic Escherichia coli (EtEc and PEPEc) strains are agents associated with swine neonatal diarrhea, causing economic losses in swine production. The main goal of this study was to identify virulence genes of EtEc, verotoxigenic (VtEc) and PEPEc in intestinal strains responsible for swine diseases, by molecular typing using Pcr in newborn piglets from an intensive farm system. Two hundred and sixty seven rectal swabbings from 7-15 days- old landrace x large White crossbred piglets were taken, and 123 randomly selected samples, biochemically compatible with E. coli, were tested for E. coli virulence genes by Pcr. A frequency (%) compatible with: 68 EtEc, 24 VtEc, and 8 EPEc were found. of all E. coli strains studied, 19.51 % carried at least one virulence gene. These data showed conclusively that, in spite of the application of strict sanitary measures in the intensive farm, genes encoding virulence factors of intestinal pathogens compatible with EtEc are still detected; therefore these strains will probably keep circulating among animals. PMID:23267620

  12. Construction of intensity-duration-frequency (IDF) curves for precipitation with annual maxima data in Rwanda, Central Africa

    NASA Astrophysics Data System (ADS)

    Demarée, G. R.; Van de Vyver, H.

    2013-06-01

    Detailed probabilistic information on the intensity of precipitation in Central Africa is highly needed in order to cope with the risk analysis of natural hazards. In the mountainous areas of Rwanda land slides frequently occur and might cause a heavy toll in human lives. The establishment of Intensity-Duration-Frequency curves for precipitation in Central Africa remains a difficult task as adequate long-term data sets for short aggregation times are usually not available. In 1962 recording raingauges were installed at several stations in Rwanda. According to the climatological procedures in use at that time in Congo, Rwanda and Burundi, maximum monthly and annual precipitation depths for fixed-time durations of 15, 30, 45, 60 and 120 min were determined from the rainfall charts. The data set is completed by the monthly and annual daily precipitation extremes from the non-recording raingauge at the stations. The authors used the dataset to establish the IDF-curves for precipitation at 3 stations in Rwanda having more than 20 yr of operation. The fixed-hour intervals of multiple 15 min require the use of a technique converting data from fixed-time intervals into data of arbitrary starting intervals. Therefore, the van Montfort technique was used.

  13. Uncertainty Characterization and Delineation of Nonstationarity in Intensity-Duration-Frequency Curves of Precipitation Relevant for Infrastructural Design

    NASA Astrophysics Data System (ADS)

    Kumar, D.; Ganguly, A. R.

    2014-12-01

    Understanding the degree of stationarity in intensity-duration-frequency (IDF) curves of precipitation extremes relates to the design and maintenance of hydraulic infrastructures and hence to flood resilience. Statistical analysis of observations and climate models forced with projected emissions scenarios point to more frequent and intense precipitation extremes at global and century scales. A statistical delineation of changes in IDF curves at scales relevant for infrastructures has proved elusive, owing to significant spatial variability, data and model quality, and estimation uncertainties. The contribution of climate internal variability, in addition to thresholds and intermittences, has not received much attention in the literature. However, this relatively irreducible component of the uncertainty may dominate for decadal planning horizons, especially at the spatial scales relevant for hydraulic infrastructures. A characterization of the irreducible uncertainties, which in turn yields an envelope of plausible scenarios, may need to be a critical pathway for resilient engineering. Statistical and information theoretic methods are developed or adapted from the literature to characterize predictability and nonstationarity of IDF curves. Risk management methods are examined to develop best practices for translating the characterization of irreducible uncertainty to guidelines for infrastructural decisions and resource allocations.

  14. Effects of a Low-Intensity Laser on Dental Implant Osseointegration: Removal Torque and Resonance Frequency Analysis in Rabbits.

    PubMed

    Blay, Alberto; Blay, Claudia C; Tunchel, Samy; Gehrke, Sergio Alexandre; Shibli, Jamil Awad; Groth, Eduardo B; Zezell, Denise M

    2016-08-01

    The objective of this study was to investigate how a low-intensity laser affects the stability and reverse torque resistance of dental implants installed in the tibia of rabbits. Thirty rabbits received 60 dental implants with the same design and surface treatment, one in each proximal metaphysis of the tibia. Three groups were prepared (n = 10 animals each): conventional osseointegration without treatment (control group), surgical sites irradiated with a laser beam emitted in the visible range of 680 nm (Lg1 group), surgical sites irradiated with a laser beam with a wavelength in the infrared range of 830 nm (Lg2 group). Ten irradiation sessions were performed 48 hours apart; the first session was during the immediate postoperative period. Irradiation energy density was 4 J/cm(2) per point in 2 points on each side of the tibias. The resonance frequency and removal torque values were measured at 2 time points after the implantations (3 and 6 weeks). Both laser groups (Lg1 and Lg2) presented a significant difference between resonance frequency analysis values at the baseline and the values obtained after 3 and 6 weeks (P > .05). Although the removal torque values of all groups increased after 6 weeks (P < .05), both laser groups presented greater mean values than those of the control group (P < .01). Photobiomodulation using laser irradiation with wavelengths of 680 and 830 nm had a better degree of bone integration than the control group after 6 weeks of observation time.

  15. Frequency tuning and intensity coding of sound in the auditory periphery of the lake sturgeon, Acipenser fulvescens

    PubMed Central

    Meyer, Michaela; Fay, Richard R.; Popper, Arthur N.

    2010-01-01

    Acipenser fulvescens, the lake sturgeon, belongs to one of the few extant non-teleost ray-finned (bony) fishes. The sturgeons (family Acipenseridae) have a phylogenetic history that dates back about 250 million years. The study reported here is the first investigation of peripheral coding strategies for spectral analysis in the auditory system in a non-teleost bony fish. We used a shaker system to simulate the particle motion component of sound during electrophysiological recordings of isolated single units from the eighth nerve innervating the saccule and lagena. Background activity and response characteristics of saccular and lagenar afferents (such as thresholds, response–level functions and temporal firing) resembled the ones found in teleosts. The distribution of best frequencies also resembled data in teleosts (except for Carassius auratus, goldfish) tested with the same stimulation method. The saccule and lagena in A. fulvescens contain otoconia, in contrast to the solid otoliths found in teleosts, however, this difference in otolith structure did not appear to affect threshold, frequency tuning, intensity- or temporal responses of auditory afferents. In general, the physiological characteristics common to A. fulvescens, teleosts and land vertebrates reflect important functions of the auditory system that may have been conserved throughout the evolution of vertebrates. PMID:20400642

  16. [Effect of Low-Intensity 900 MHz Frequency Electromagnetic Radiation on Rat Brain Enzyme Activities Linked to Energy Metabolism].

    PubMed

    Petrosyan, M S; Nersesova, L S; Gazaryants, M G; Meliksetyan, G O; Malakyan, M G; Bajinyan, S A; Akopian, J I

    2015-01-01

    The research deals with the effect of low-intensity 900 MHz frequency electromagnetic radiation (EMR), power density 25 μW/cm2, on the following rat brain and blood serum enzyme activities: creatine kinase (CK), playing a central role in the process of storing and distributing the cell energy, as well as alanine aminotransferase (ALT) and aspartate aminotransferase (AST) that play a key role in providing the conjunction of carbohydrate and amino acid metabolism. The comparative analysis of the changes in the enzyme activity studied at different times following the two-hour single, as well as fractional, radiation equivalent of the total time showed that the most radiosensitive enzyme is the brain creatine kinase, which may then be recommended as a marker of the radio frequency radiation impact. According to the analysis of the changing dynamics of the CK, ALT and AST activity level, with time these changes acquire the adaptive character and are directed to compensate the damaged cell energy metabolism.

  17. Determination of the effect of source intensity profile on speckle contrast using coherent spatial frequency domain imaging

    PubMed Central

    Rice, Tyler B.; Konecky, Soren D.; Owen, Christopher; Choi, Bernard; Tromberg, Bruce J.

    2012-01-01

    Laser Speckle Imaging (LSI) is fast, noninvasive technique to image particle dynamics in scattering media such as biological tissue. While LSI measurements are independent of the overall intensity of the laser source, we find that spatial variations in the laser source profile can impact measured flow rates. This occurs due to differences in average photon path length across the profile, and is of significant concern because all lasers have some degree of natural Gaussian profile in addition to artifacts potentially caused by projecting optics. Two in vivo measurement are performed to show that flow rates differ based on location with respect to the beam profile. A quantitative analysis is then done through a speckle contrast forward model generated within a coherent Spatial Frequency Domain Imaging (cSFDI) formalism. The model predicts remitted speckle contrast as a function of spatial frequency, optical properties, and scattering dynamics. Comparison with experimental speckle contrast images were done using liquid phantoms with known optical properties for three common beam shapes. cSFDI is found to accurately predict speckle contrast for all beam shapes to within 5% root mean square error. Suggestions for improving beam homogeneity are given, including a widening of the natural beam Gaussian, proper diffusing glass spreading, and flat top shaping using microlens arrays. PMID:22741080

  18. Compression? Yes, but for low or high frequencies, for low or high intensities, and with what response times?

    PubMed

    Dillon, H

    1996-08-01

    Several rationales for using compression in hearing aids are outlined. These rationales comprise discomfort avoidance, loudness normalization, noise reduction, short term signal dynamic range reduction, empirically determined compression, and long-term signal dynamic range reduction. The compression systems needed to implement each of these differ greatly, and these differences can be viewed as differences in the frequency range undergoing most compression, the intensity range undergoing most compression, and the speed at which the compressor(s) operate. A classification system along these lines is introduced and examples of currently available hearing aids falling into each category are given. The effects of each type of compression on speech intelligibility is investigated via a review of published research. The results of this indicate that, for speech in quiet at a comfortable level, no compression scheme yet tested offers better intelligibility than individually selected linear amplification. If input level is then decreased and the aid wearer is prevented from adjusting the volume control, many types of compression provide intelligibility superior to that available from linear amplification. In broadband noise, only one system, containing wideband compression followed by fast acting high-frequency compression, has so far been shown to provide significant intelligibility advantages.

  19. Semantic Web-based integration of cancer pathways and allele frequency data.

    PubMed

    Holford, Matthew E; Rajeevan, Haseena; Zhao, Hongyu; Kidd, Kenneth K; Cheung, Kei-Hoi

    2009-01-01

    We demonstrate the use of Semantic Web technology to integrate the ALFRED allele frequency database and the Starpath pathway resource. The linking of population-specific genotype data with cancer-related pathway data is potentially useful given the growing interest in personalized medicine and the exploitation of pathway knowledge for cancer drug discovery. We model our data using the Web Ontology Language (OWL), drawing upon ideas from existing standard formats BioPAX for pathway data and PML for allele frequency data. We store our data within an Oracle database, using Oracle Semantic Technologies. We then query the data using Oracle's rule-based inference engine and SPARQL-like RDF query language. The ability to perform queries across the domains of population genetics and pathways offers the potential to answer a number of cancer-related research questions. Among the possibilities is the ability to identify genetic variants which are associated with cancer pathways and whose frequency varies significantly between ethnic groups. This sort of information could be useful for designing clinical studies and for providing background data in personalized medicine. It could also assist with the interpretation of genetic analysis results such as those from genome-wide association studies.

  20. Reduced Acute Bowel Toxicity in Patients Treated With Intensity-Modulated Radiotherapy for Rectal Cancer

    SciTech Connect

    Samuelian, Jason M.; Callister, Matthew D.; Ashman, Jonathan B.; Young-Fadok, Tonia M.; Borad, Mitesh J.; Gunderson, Leonard L.

    2012-04-01

    Purpose: We have previously shown that intensity-modulated radiotherapy (IMRT) can reduce dose to small bowel, bladder, and bone marrow compared with three-field conventional radiotherapy (CRT) technique in the treatment of rectal cancer. The purpose of this study was to review our experience using IMRT to treat rectal cancer and report patient clinical outcomes. Methods and Materials: A retrospective review was conducted of patients with rectal cancer who were treated at Mayo Clinic Arizona with pelvic radiotherapy (RT). Data regarding patient and tumor characteristics, treatment, acute toxicity according to the Common Terminology Criteria for Adverse Events v 3.0, tumor response, and perioperative morbidity were collected. Results: From 2004 to August 2009, 92 consecutive patients were treated. Sixty-one (66%) patients were treated with CRT, and 31 (34%) patients were treated with IMRT. All but 2 patients received concurrent chemotherapy. There was no significant difference in median dose (50.4 Gy, CRT; 50 Gy, IMRT), preoperative vs. postoperative treatment, type of concurrent chemotherapy, or history of previous pelvic RT between the CRT and IMRT patient groups. Patients who received IMRT had significantly less gastrointestinal (GI) toxicity. Sixty-two percent of patients undergoing CRT experienced {>=}Grade 2 acute GI side effects, compared with 32% among IMRT patients (p = 0.006). The reduction in overall GI toxicity was attributable to fewer symptoms from the lower GI tract. Among CRT patients, {>=}Grade 2 diarrhea and enteritis was experienced among 48% and 30% of patients, respectively, compared with 23% (p = 0.02) and 10% (p = 0.015) among IMRT patients. There was no significant difference in hematologic or genitourinary acute toxicity between groups. In addition, pathologic complete response rates and postoperative morbidity between treatment groups did not differ significantly. Conclusions: In the management of rectal cancer, IMRT is associated with a

  1. Outcomes After Intensity-Modulated Versus Conformal Radiotherapy in Older Men With Nonmetastatic Prostate Cancer

    SciTech Connect

    Bekelman, Justin E.; Mitra, Nandita; Efstathiou, Jason; Liao Kaijun; Sunderland, Robert; Yeboa, Deborah N.; Armstrong, Katrina

    2011-11-15

    Purpose: There is little evidence comparing complications after intensity-modulated (IMRT) vs. three-dimensional conformal radiotherapy (CRT) for prostate cancer. The study objective was to test the hypothesis that IMRT, compared with CRT, is associated with a reduction in bowel, urinary, and erectile complications in elderly men with nonmetastatic prostate cancer. Methods and Materials: We undertook an observational cohort study using registry and administrative claims data from the SEER-Medicare database. We identified men aged 65 years or older diagnosed with nonmetastatic prostate cancer in the United States between 2002 and 2004 who received IMRT (n = 5,845) or CRT (n = 6,753). The primary outcome was a composite measure of bowel complications. Secondary outcomes were composite measures of urinary and erectile complications. We also examined specific subsets of bowel (proctitis/hemorrhage) and urinary (cystitis/hematuria) events within the composite complication measures. Results: IMRT was associated with reductions in composite bowel complications (24-month cumulative incidence 18.8% vs. 22.5%; hazard ratio [HR] 0.86; 95% confidence interval [CI], 0.79-0.93) and proctitis/hemorrhage (HR 0.78; 95% CI, 0.64-0.95). IMRT was not associated with rates of composite urinary complications (HR 0.93; 95% CI, 0.83-1.04) or cystitis/hematuria (HR 0.94; 95% CI, 0.83-1.07). The incidence of erectile complications involving invasive procedures was low and did not differ significantly between groups, although IMRT was associated with an increase in new diagnoses of impotence (HR 1.27, 95% CI, 1.14-1.42). Conclusion: IMRT is associated with a small reduction in composite bowel complications and proctitis/hemorrhage compared with CRT in elderly men with nonmetastatic prostate cancer.

  2. Adoption of Intensity Modulated Radiation Therapy For Early-Stage Breast Cancer From 2004 Through 2011

    SciTech Connect

    Wang, Elyn H.; Mougalian, Sarah S.; Soulos, Pamela R.; Smith, Benjamin D.; Haffty, Bruce G.; Gross, Cary P.; Yu, James B.

    2015-02-01

    Purpose: Intensity modulated radiation therapy (IMRT) is a newer method of radiation therapy (RT) that has been increasingly adopted as an adjuvant treatment after breast-conserving surgery (BCS). IMRT may result in improved cosmesis compared to standard RT, although at greater expense. To investigate the adoption of IMRT, we examined trends and factors associated with IMRT in women under the age of 65 with early stage breast cancer. Methods and Materials: We performed a retrospective study of early stage breast cancer patients treated with BCS followed by whole-breast irradiation (WBI) who were ≤65 years old in the National Cancer Data Base from 2004 to 2011. We used logistic regression to identify factors associated with receipt of IMRT (vs standard RT). Results: We identified 11,089 women with early breast cancer (9.6%) who were treated with IMRT and 104,448 (90.4%) who were treated with standard RT, after BCS. The proportion of WBI patients receiving IMRT increased yearly from 2004 to 2009, with 5.3% of WBI patients receiving IMRT in 2004 and 11.6% receiving IMRT in 2009. Further use of IMRT declined afterward, with the proportion remaining steady at 11.0% and 10.7% in 2010 and 2011, respectively. Patients treated in nonacademic community centers were more likely to receive IMRT (odds ratio [OR], 1.36; 95% confidence interval [CI], 1.30-1.43 for nonacademic vs academic center). Compared to privately insured patients, the uninsured patients (OR, 0.81; 95% CI, 0.70-0.95) and those with Medicaid insurance (OR, 0.87; 95% CI, 0.79-0.95) were less likely to receive IMRT. Conclusions: The use of IMRT rose from 2004 to 2009 and then stabilized. Important nonclinical factors associated with IMRT use included facility type and insurance status.

  3. Effects of the intensity of masking noise on ear canal recorded low-frequency cochlear microphonic waveforms in normal hearing subjects.

    PubMed

    Zhang, Ming

    2014-07-01

    Compared to auditory brainstem responses (ABRs), cochlear microphonics (CMs) may be more appropriate to serve as a supplement to the test of otoacoustic emissions (OAEs). Researchers have shown that low-frequency CMs from the apical cochlea are measurable at the tympanic membrane using high-pass masking noise. Our objective is to study the effect of such noise at different intensities on low-frequency CMs recorded at the ear canal, which is not completely known. Six components were involved in this CM measurement including an ear canal electrode (1), a relatively long and low-frequency toneburst (2), and high-pass masking noise at different intensities (3). The rest components include statistical analysis based on multiple human subjects (4), curve modeling based on amplitudes of CM waveforms (CMWs) and noise intensity (5), and a technique based on electrocochleography (ECochG or ECoG) (6). Results show that low-frequency CMWs appeared clearly. The CMW amplitude decreased with an increase in noise level. It decreased first slowly, then faster, and finally slowly again. In conclusion, when masked with high-pass noise, the low-frequency CMs are measurable at the human ear canal. Such noise reduces the low-frequency CM amplitude. The reduction is noise-intensity dependent but not completely linear. The reduction may be caused by the excited basal cochlea which the low-frequency has to travel and pass through. Although not completely clear, six mechanisms related to such reduction are discussed.

  4. Hypofractionated Intensity-Modulated Arc Therapy for Lymph Node Metastasized Prostate Cancer

    SciTech Connect

    Fonteyne, Valerie; De Gersem, Werner; De Neve, Wilfried; Jacobs, Filip; Lumen, Nicolaas; Vandecasteele, Katrien; Villeirs, Geert; De Meerleer, Gert

    2009-11-15

    Purpose: To determine the planning results and acute toxicity after hypofractionated intensity-modulated arc radiotherapy and androgen deprivation for lymph node metastasized (Stage N1) prostate cancer. Methods and Materials: A total of 31 patients with Stage T1-T4N1M0 prostate cancer were treated with intensity-modulated arc radiotherapy and 3 years of androgen deprivation as primary treatment. The clinical target volume (CTV{sub p}) was the prostate and seminal vesicles. Elective lymph node areas ({sub e}) were delineated and expanded by 2 mm to create the CTV{sub e}. The planning target volumes (PTV{sub p} and PTV{sub e}) were created using a three-dimensional expansion of the CTV{sub p} and CTV{sub e}, respectively, of 7 mm. A median dose of 69.3 Gy and 50 Gy was prescribed to the PTV{sub p} and PTV{sub e} respectively, to be delivered in 25 fractions. Upper and lower gastrointestinal toxicity was scored using the Radiation Therapy Oncology Group toxicity and radiotherapy-induced lower intestinal toxicity scoring system. Genitourinary toxicity was scored using a combined Radiation Therapy Oncology Group, LENT-SOMA (late effects normal tissue-subjective, objective, management, analytic), and Common Toxicity Criteria toxicity scoring system. Results: The median follow-up time was 3 months. The mean prescription dose to the CTV{sub p} and PTV{sub p} was 70.4 Gy and 68.6 Gy, respectively. The minimal dose to the CTV{sub e} and PTV{sub e} was 49.0 Gy and 47.0 Gy, respectively. No acute Grade 2 or greater gastrointestinal toxicity occurred. Fourteen patients developed acute Grade 2 lower gastrointestinal toxicity. Acute Grade 3 and 2 genitourinary toxicity developed in 2 and 14 patients, respectively. Conclusion: The results of our study have shown that hypofractionated intensity-modulated arc radiotherapy as primary therapy for N1 prostate cancer is feasible with low toxicity.

  5. Apolipoprotein E Allelic Frequency Altered in Women with Early-onset Breast Cancer.

    PubMed

    Porrata-Doria, Tirtsa; Matta, Jaime L; Acevedo, Summer F

    2010-05-24

    Among women, the most prevalent type of cancer is breast cancer, affecting 1 out of every 8 women in the United States; in Puerto Rico, 70 out of every 100,000 will develop some type of breast cancer. Therefore, a better understand of the potential risk factors for breast cancer could lead to the development of early detection tools. A gene that has been proposed as a risk factor in several populations around the world is Apolipoprotein E (apoE). ApoE functions as a mechanism of transport for lipoproteins and cholesterol throughout the body, with 3 main isoforms present in humans (apoE2, apoE3, and apoE4). Whether or not apoE4 is a risk factor for breast cancer remains controversial. Previous studies have either included test subjects of all ages (20-80) or have focused on late-onset (after age 50) breast cancer; none has concentrated specifically on early-onset (aged 50 and younger) breast cancer. The objectives of this study was to examine (in a Puerto Rican population) the differences in the relative frequency of occurrence of apoE4 in non-breast cancer versus breast cancer patients and to examine, as well, the potential differences of same in early- versus late-onset patients. We found an increased frequency of apoE4 (odds ratio 2.15) only in early-onset breast cancer survivors, which is similar to the findings of those studies that combined or adjusted for age as well as for an association between apoE4 and decreased tumor size. ApoE is also a potential risk factor for long-term cognitive effects after chemotherapy and affects response to hormone replacement. Our data supports the theory that knowing the apoE genotype of women who are at risk of developing breast cancer may be beneficial, as such knowledge would aid in the prediction of tumor size and the development of treatment regimens.

  6. Low-frequency Intensity Variation of the South Asian High and its relationship to Boreal Summer Intraseasonal Oscillation

    NASA Astrophysics Data System (ADS)

    Shang, Wei; Ren, Xuejuan

    2016-04-01

    and northwest from day -12 to day 0 is associated with the Boreal Summer Intraseasonal Oscillation 2 (BSISO 2) of 10 - 30 days in the Asian monsoon areas. When BSISO2 propagates from subtropics to Asian continents , more anomalous rainfall appear in the Asian monsoon areas, which correspond more anomalous condensation heat release. The anomalous heating stimulate positive height anomalies with an anomalous anticyclonic circulation to its northwest in the upper troposphere, causing the strengthening of the SAH intensity. In addition, the strengthening of the west part of SAH may result from an anomalous low-frequency anticyclonic in the upper troposphere propagating northward from Arabian Sea to Iranian plateau.

  7. Intensity-Modulated Radiotherapy for Head-and-Neck Cancer in the Community Setting

    SciTech Connect

    Seung, Steven Bae, Joseph; Solhjem, Matthew; Bader, Stephen; Gannett, David; Hansen, Eric K.; Louie, Jeannie; Underhill, Kelly Cha Christine

    2008-11-15

    Purpose: To review outcomes with intensity-modulated radiation therapy (IMRT) in the community setting for the treatment of nasopharyngeal and oropharyngeal cancer. Methods and Materials: Between April 2003 and April 2007, 69 patients with histologically confirmed cancer of the nasopharynx and oropharynx underwent IMRT in our practice. The primary sites included nasopharynx (11), base of tongue (18), and tonsil (40). The disease stage distribution was as follows: 2 Stage I, 11 Stage II, 16 Stage III, and 40 Stage IV. All were treated with a simultaneous integrated boost IMRT technique. The median prescribed doses were 70 Gy to the planning target volume, 59.4 Gy to the high-risk subclinical volume, and 54 Gy to the low-risk subclinical volume. Forty-five patients (65%) received concurrent chemotherapy. Toxicity was graded according to the Radiation Therapy Oncology Group toxicity criteria. Progression-free and overall survival rates were estimated with the Kaplan-Meier product-limit method. Results: Median duration of follow-up was 18 months. The estimated 2-year local control, regional control, distant control, and overall survival rates were 98%, 100%, 98%, and 90%, respectively. The most common acute toxicities were dermatitis (32 Grade 1, 32 Grade 2, 5 Grade 3), mucositis (8 Grade 1, 33 Grade 2, 28 Grade 3), and xerostomia (0 Grade 1, 29 Grade 2, 40 Grade 3). Conclusions: Intensity-modulated radiotherapy in the community setting can be accomplished safely and effectively. Systematic internal review systems are recommended for quality control until sufficient experience develops.

  8. Radio-frequency radiation exposure from AM radio transmitters and childhood leukemia and brain cancer.

    PubMed

    Ha, Mina; Im, Hyoungjune; Lee, Mihye; Kim, Hyun Joo; Kim, Byung-Chan; Gimm, Yoon-Myoung; Pack, Jeong-Ki

    2007-08-01

    Leukemia and brain cancer patients under age 15 years, along with controls with respiratory illnesses who were matched to cases on age, sex, and year of diagnosis (1993-1999), were selected from 14 South Korean hospitals using the South Korean Medical Insurance Data System. Diagnoses were confirmed through the South Korean National Cancer Registry. Residential addresses were obtained from medical records. A newly developed prediction program incorporating a geographic information system that was modified by the results of actual measurements was used to estimate radio-frequency radiation (RFR) exposure from 31 amplitude modulation (AM) radio transmitters with a power of 20 kW or more. A total of 1,928 leukemia patients, 956 brain cancer patients, and 3,082 controls were analyzed. Cancer risks were estimated using conditional logistic regression adjusted for residential area, socioeconomic status, and community population density. The odds ratio for all types of leukemia was 2.15 (95% confidence interval (CI): 1.00, 4.67) among children who resided within 2 km of the nearest AM radio transmitter as compared with those resided more than 20 km from it. For total RFR exposure from all transmitters, odds ratios for lymphocytic leukemia were 1.39 (95% CI: 1.04, 1.86) and 1.59 (95% CI: 1.19, 2.11) for children in the second and third quartiles, respectively, versus the lowest quartile. Brain cancer and infantile cancer were not associated with AM RFR.

  9. Extremely low frequency electromagnetic fields (EMF) and brain cancer in adults and children: review and comment.

    PubMed Central

    Gurney, J. G.; van Wijngaarden, E.

    1999-01-01

    Epidemiologic and experimental research on the potential carcinogenic effects of extremely low frequency electromagnetic fields (EMF) has now been conducted for over two decades. Cancer epidemiology studies in relation to EMF have focused primarily on brain cancer and leukemia, both from residential sources of exposure in children and adults and from occupational exposure in adult men. Because genotoxic effects of EMF have not been shown, most recent laboratory research has attempted to show biological effects that could be related to cancer promotion. In this report, we briefly review residential and occupational EMF studies on brain cancer. We also provide a general review of experimental studies as they relate both to the biological plausibility of an EMF-brain cancer relation and to the insufficiency of such research to help guide exposure assessment in epidemiologic studies. We conclude from our review that no recent research, either epidemiologic or experimental, has emerged to provide reasonable support for a causal role of EMF on brain cancer. PMID:11550314

  10. End-of-Life Care Intensity among Adolescent and Young Adult Cancer Patients in Kaiser Permanente Southern California

    PubMed Central

    Mack, Jennifer W.; Chen, Lie H.; Cannavale, Kimberley; Sattayapiwat, Olivia; Cooper, Robert M.; Chao, Chun R.

    2015-01-01

    Importance Cancer is the leading disease-related cause of death among adolescents and young adults (AYAs), but little is known about the care that AYA patients with cancer receive at the end of life (EOL). Objective To evaluate the intensity of EOL care among AYA cancer patients. Design Cross-sectional study using cancer registry and electronic health record data. Setting Kaiser Permanente Southern California (KSPC), an integrated health care delivery system. Participants 663 AYA patients with either (1) stage I-III cancer and evidence of cancer recurrence or (2) stage IV cancer at diagnosis who received care in KPSC and died in the years 2001–2010. Patients were eligible if they were aged 15–39 at death. Main Outcome Measures Chemotherapy use in the last 14 days of life, intensive care unit (ICU) care in the last 30 days of life, more than one emergency room (ER) visit in the last 30 days of life, hospitalization in the last 30 days of life, and a composite measure of medically intensive EOL care comprising any of the aforementioned measures. Results 11% of patients (72/663) received chemotherapy within 14 days of death. In the last 30 days of life, 22% of patients (144/663) were admitted to the ICU; 22% (147/663) had >1 ER visit; and 62% (413/663) were hospitalized. Overall, 68% (449/663) of subjects received at least one medically intensive EOL care measure. Conclusions and Relevance Most AYA patients receive at least one form of medically intensive EOL care. These findings suggest the need to better understand EOL care preferences and decision-making in this young population. PMID:26181778

  11. Comprehensive experimental and numerical investigations of the effect of frequency and acoustic intensity on the sonolytic degradation of naphthol blue black in water.

    PubMed

    Ferkous, Hamza; Merouani, Slimane; Hamdaoui, Oualid; Rezgui, Yacine; Guemini, Miloud

    2015-09-01

    In the present work, comprehensive experimental and numerical investigations of the effects of frequency and acoustic intensity on the sonochemical degradation of naphthol blue black (NBB) in water have been carried out. The experiments have been examined at three frequencies (585, 860 and 1140 kHz) and over a wide range of acoustic intensities. The observed experimental results have been discussed using a more realistic approach that combines the single bubble sonochemistry and the number of active bubbles. The single bubble yield has been predicted using a model that combines the bubble dynamics with chemical kinetics consisting of series of chemical reactions (73 reversible reactions) occurring inside an air bubble during the strong collapse. The experimental results showed that the sonochemical degradation rate of NBB increased substantially with increasing acoustic intensity and decreased with increasing ultrasound frequency. The numerical simulations revealed that NBB degraded mainly through the reaction with hydroxyl radical (OH), which is the dominant oxidant detected in the bubble during collapse. The production rate of OH radical inside a single bubble followed the same trend as that of NBB degradation rate. It increased with increasing acoustic intensity and decreased with increasing frequency. The enhancing effect of acoustic intensity toward the degradation of NBB was attributed to the rise of both the individual chemical bubble yield and the number of active bubbles with increasing acoustic intensity. The reducing effect of frequency was attributed to the sharp decrease in the chemical bubble yield with increasing frequency, which would not compensated by the rise of the number of active bubbles with the increase in ultrasound frequency. PMID:25753313

  12. 68Ga-PSMA PET/MR Showing Intense PSMA Uptake in Nodular Fasciitis Mimicking Prostate Cancer Metastasis.

    PubMed

    Henninger, Martin; Maurer, Tobias; Hacker, Charlotte; Eiber, Matthias

    2016-10-01

    The recently introduced PSMA PET has developed as a powerful imaging tool for staging of prostate cancer. This case showed an intense uptake of Ga-PSMA in a soft-tissue mass of the rectus femoris muscle. Histopathology revealed the diagnosis of fasciitis nodularis. Therefore, it advises caution particularly in patients with solitary and atypical located lesions as they might not be indicative for metastatic prostate cancer, but eventually be caused by different conditions. PMID:27488427

  13. 68Ga-PSMA PET/MR Showing Intense PSMA Uptake in Nodular Fasciitis Mimicking Prostate Cancer Metastasis.

    PubMed

    Henninger, Martin; Maurer, Tobias; Hacker, Charlotte; Eiber, Matthias

    2016-10-01

    The recently introduced PSMA PET has developed as a powerful imaging tool for staging of prostate cancer. This case showed an intense uptake of Ga-PSMA in a soft-tissue mass of the rectus femoris muscle. Histopathology revealed the diagnosis of fasciitis nodularis. Therefore, it advises caution particularly in patients with solitary and atypical located lesions as they might not be indicative for metastatic prostate cancer, but eventually be caused by different conditions.

  14. Characterization of nonmelanoma skin cancer for light therapy using spatial frequency domain imaging

    PubMed Central

    Rohrbach, Daniel J.; Zeitouni, Nathalie C.; Muffoletto, Daniel; Saager, Rolf; Tromberg, Bruce J.; Sunar, Ulas

    2015-01-01

    The dosimetry of light-based therapies critically depends on both optical and vascular parameters. We utilized spatial frequency domain imaging to quantify optical and vascular parameters, as well as estimated light penetration depth from 17 nonmelanoma skin cancer patients. Our data indicates that there exist substantial spatial variations in these parameters. Characterization of these parameters may inform understanding and optimization of the clinical response of light-based therapies. PMID:26137378

  15. Marginal Misses After Postoperative Intensity-Modulated Radiotherapy for Head and Neck Cancer

    SciTech Connect

    Chen, Allen M.; Farwell, D. Gregory; Luu, Quang; Chen, Leon M.; Vijayakumar, Srinivasan; Purdy, James A.

    2011-08-01

    Purpose: To describe the spatial distribution of local-regional recurrence (LRR) among patients treated postoperatively with intensity-modulated radiotherapy (IMRT) for head and neck cancer. Methods and Materials: The medical records of 90 consecutive patients treated by gross total resection and postoperative IMRT for squamous cell carcinoma of the head and neck from January 2003 to July 2009 were reviewed. Sites of disease were the oral cavity (43 patients), oropharynx (20 patients), larynx (15 patients), and hypopharynx (12 patients). Fifty patients (56%) received concurrent chemotherapy. Results: Seventeen of 90 patients treated with postoperative IMRT experienced LRR, yielding a 2-year estimate of local regional control of 80%. Among the LRR patients, 11 patients were classified as in-field recurrences, occurring within the physician-designated clinical target volume, and 6 patients were categorized as marginal recurrences. There were no out-of-field geographical misses. Sites of marginal LRRs included the contralateral neck adjacent to the spared parotid gland (3 patients), the dermal/subcutaneous surface (2 patients), and the retropharyngeal/retrostyloid lymph node region (1 patient). Conclusions: Although the incidence of geographical misses was relatively low, the possibility of this phenomenon should be considered in the design of target volumes among patients treated by postoperative IMRT for head and neck cancer.

  16. A novel high intensity focused ultrasound robotic system for breast cancer treatment.

    PubMed

    Yonetsuji, Taizan; Ando, Takehiro; Wang, Junchen; Fujiwara, Keisuke; Itani, Kazunori; Azuma, Takashi; Yoshinaka, Kiyoshi; Sasaki, Akira; Takagi, Shu; Kobayashi, Etsuko; Liao, Hongen; Matsumoto, Yoichiro; Sakuma, Ichiro

    2013-01-01

    High intensity focused ultrasound (HIFU) is a promising technique for cancer treatment owing to its minimal invasiveness and safety. However, skin burn, long treatment time and incomplete ablation are main shortcomings of this method. This paper presents a novel HIFU robotic system for breast cancer treatment. The robot has 4 rotational degrees of freedom with the workspace located in a water tank for HIFU beam imaging and ablation treatment. The HIFU transducer combined with a diagnostic 2D linear ultrasound probe is mounted on the robot end-effector, which is rotated around the HIFU focus when ablating the tumor. HIFU beams are visualized by the 2D probe using beam imaging. Skin burn can be prevented or alleviated by avoiding long time insonification towards the same skin area. The time cost could be significantly reduced, as there is no need to interrupt the ablation procedure for cooling the skin. In addition, our proposed robot control strategies can avoid incomplete ablation. Experiments were carried out and the results showed the effectiveness of our proposed system. PMID:24505785

  17. A novel high intensity focused ultrasound robotic system for breast cancer treatment.

    PubMed

    Yonetsuji, Taizan; Ando, Takehiro; Wang, Junchen; Fujiwara, Keisuke; Itani, Kazunori; Azuma, Takashi; Yoshinaka, Kiyoshi; Sasaki, Akira; Takagi, Shu; Kobayashi, Etsuko; Liao, Hongen; Matsumoto, Yoichiro; Sakuma, Ichiro

    2013-01-01

    High intensity focused ultrasound (HIFU) is a promising technique for cancer treatment owing to its minimal invasiveness and safety. However, skin burn, long treatment time and incomplete ablation are main shortcomings of this method. This paper presents a novel HIFU robotic system for breast cancer treatment. The robot has 4 rotational degrees of freedom with the workspace located in a water tank for HIFU beam imaging and ablation treatment. The HIFU transducer combined with a diagnostic 2D linear ultrasound probe is mounted on the robot end-effector, which is rotated around the HIFU focus when ablating the tumor. HIFU beams are visualized by the 2D probe using beam imaging. Skin burn can be prevented or alleviated by avoiding long time insonification towards the same skin area. The time cost could be significantly reduced, as there is no need to interrupt the ablation procedure for cooling the skin. In addition, our proposed robot control strategies can avoid incomplete ablation. Experiments were carried out and the results showed the effectiveness of our proposed system.

  18. High-frequency, high-intensity transcutaneous electrical nerve stimulation as treatment of pain after surgical abortion.

    PubMed

    Platon, B; Andréll, P; Raner, C; Rudolph, M; Dvoretsky, A; Mannheimer, C

    2010-01-01

    The aim of the study was to compare the pain-relieving effect and the time spent in the recovery ward after treatment with high-frequency, high-intensity transcutaneous electrical nerve stimulation (TENS) or intravenous (IV) conventional pharmacological treatment after surgical abortion. Two-hundred women who underwent surgical abortion and postoperatively reported a visual analogue scale (VAS) pain score3 were included. The patients were randomised to TENS or conventional pharmacological treatment for their postoperative pain. The TENS treatment was given with a stimulus intensity between 20 and 60 mA during 1 min and repeated once if insufficient pain relief (VAS3). In the conventional pharmacological treatment group, a maximum dose of 100 microg fentanyl was given IV. There was no difference between the groups with regard to pain relief according to the VAS pain score (TENS=VAS 1.3 vs. IV opioids=VAS 1.6; p=0.09) upon discharge from the recovery ward. However, the patients in the TENS group spent shorter time (44 min) in the recovery ward than the conventional pharmacological treatment group (62 min; p<0.0001). The number of patients who needed additional analgesics in the recovery ward was comparable in both groups, as was the reported VAS pain score upon leaving the hospital (TENS=2.0 vs. conventional pharmacological treatment=1.8, NS). These results suggest that the pain-relieving effect of TENS seems to be comparable to conventional pharmacological treatment with IV opioids. Hence, TENS may be a suitable alternative to conventional pain management with IV opioids after surgical abortion.

  19. [Anatomopathological behavior of gallbladder cancer. Frequency and importance of precancerous epithelial lesions of gallbladder cancer].

    PubMed

    Trujillo, C; Olaechea de Careaga, B; Uría, J L; Villagómez, G; Antelo, J

    1986-01-01

    Surgical and autopsy materials were analyzed in a period of six years at La Paz, Bolivia "Bolivian Japanese Gastroenterological Institute" (Instituto de Gastroenterología Boliviano Japonés de La Paz, Bolivia), searching for macro and microscopic appearance of gallbladder cancer. Adenocarcinoma with infiltrative growth was the most frequent finding. Cholecystitis and Cholelithiasis were present in all the cases of gallbladder cancer. Epithelial lesions such hyperplasia, atypical hyperplasia and carcinoma in situ were frequent findings in the surrounding mucosa of invasive gallbladder carcinoma and not so frequent in benign gallbladder lesions. Group V of Nevin classification was common in our cases.

  20. Carotid sparing intensity modulated radiotherapy on early glottic cancer: preliminary study

    PubMed Central

    Choi, Hoon Sik; Jeong, Bae Kwon; Jeong, Hojin; Song, Jin Ho; Kim, Jin Pyeong; Park, Jung Je; Woo, Seung Hoon

    2016-01-01

    Purpose To compare the dose distribution between carotid sparing intensity modulated radiotherapy (IMRT) and opposed lateral field technique (LAFT), and to determine the effects of carotid sparing IMRT in early glottic cancer patients who have risk factors for atherosclerosis. Materials and Methods Ten early glottic cancer patients were treated with carotid sparing IMRT. For each patient, the conventional LAFT plan was developed for comparison. IMRT and LAFT plans were compared in terms of planning target volume (PTV) coverage, conformity index, homogeneity index, and the doses to planning organ at risk volume (PRV) for carotid arteries, spinal cord and pharyngeal constrictor muscle. Results Recurrence was not observed in any patients during the follow-up period. V95% for PTV showed no significant difference between IMRT and LAFT plans, while V100% was significantly higher in the IMRT plan (95.5% vs. 94.6%, p = 0.005). The homogeneity index (11.6%) and conformity index (1.4) in the IMRT plan were significantly better than those in the LAFT plans (8.5% and 5.1, respectively) (p = 0.005). The median V5Gy (90.0%), V25Gy (13.5%), and V50Gy (0%) for carotid artery PRV in the IMRT plan were significantly lower than those in the LAFT plan (99.1%, 89.0%, and 77.3%, respectively) (p = 0.005). Conclusion Our study suggests that carotid sparing IMRT can significantly decrease the dose to carotid arteries compared to LAFT, and it would be considered for early glottic cancer patient with high risk of atherosclerosis. PMID:27104164

  1. Intensive chemotherapy as salvage treatment for solid tumors: focus on germ cell cancer

    PubMed Central

    Selle, F.; Gligorov, J.; Richard, S.; Khalil, A.; Alexandre, I.; Avenin, D.; Provent, S.; Soares, D.G.; Lotz, J.P.

    2014-01-01

    Germ cell tumors present contrasting biological and molecular features compared to many solid tumors, which may partially explain their unusual sensitivity to chemotherapy. Reduced DNA repair capacity and enhanced induction of apoptosis appear to be key factors in the sensitivity of germ cell tumors to cisplatin. Despite substantial cure rates, some patients relapse and subsequently die of their disease. Intensive doses of chemotherapy are used to counter mechanisms of drug resistance. So far, high-dose chemotherapy with hematopoietic stem cell support for solid tumors is used only in the setting of testicular germ cell tumors. In that indication, high-dose chemotherapy is given as the first or late salvage treatment for patients with either relapsed or progressive tumors after initial conventional salvage chemotherapy. High-dose chemotherapy is usually given as two or three sequential cycles using carboplatin and etoposide with or without ifosfamide. The administration of intensive therapy carries significant side effects and can only be efficiently and safely conducted in specialized referral centers to assure optimum patient care outcomes. In breast and ovarian cancer, most studies have demonstrated improvement in progression-free survival (PFS), but overall survival remained unchanged. Therefore, most of these approaches have been dropped. In germ cell tumors, clinical trials are currently investigating novel therapeutic combinations and active treatments. In particular, the integration of targeted therapies constitutes an important area of research for patients with a poor prognosis. PMID:25493378

  2. Sedentary behaviors and light-intensity activities in relation to colorectal cancer risk.

    PubMed

    Keum, NaNa; Cao, Yin; Oh, Hannah; Smith-Warner, Stephanie A; Orav, John; Wu, Kana; Fuchs, Charles S; Cho, Eunyoung; Giovannucci, Edward L

    2016-05-01

    A recent meta-analysis found that sedentary behaviors are associated with an increased colorectal cancer (CRC) risk. Yet, the finding on TV viewing time, the most widely used surrogate of sedentary behaviors, was based on only two studies. Furthermore, light-intensity activities (e.g., standing and slow walking), non-sedentary by posture but close to sedentary behaviors by Metabolic Equivalent Task values, have not been investigated in relation to CRC risk. Thus, we prospectively analyzed the relationships based on 69,715 women from Nurses' Health Study (1992-2010) and 36,806 men from Health Professionals Follow-Up Study (1988 - 2010). Throughout follow-up, time spent on sedentary behaviors including sitting watching TV and on light-intensity activities were assessed repeatedly; incidence of CRC was ascertained. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards models from each cohort. A total of 1,119 and 913 incident cases were documented from women and men, respectively. The multivariable HR comparing ≥ 21 versus < 7 hr/week of sitting watching TV was 1.21 (95% CI = 1.02 to 1.43, ptrend =.01) in women and 1.06 (95% CI = 0.84 to 1.34, ptrend =.93) in men. In women, those highly sedentary and physically less active had an approximately 41% elevated risk of CRC (95% CI = 1.03 to 1.92) compared with those less sedentary and physically more active. The other sedentary behaviors and light-intensity activities were not related to CRC risk in women or men. In conclusion, we found that prolonged sitting time watching TV was associated with an increased CRC risk in women but not in men. PMID:26649988

  3. Interfractional Dose Variations in Intensity-Modulated Radiotherapy With Breath-Hold for Pancreatic Cancer

    SciTech Connect

    Nakamura, Mitsuhiro; Shibuya, Keiko; Nakamura, Akira; Shiinoki, Takehiro; Matsuo, Yukinori; Nakata, Manabu; Sawada, Akira; Mizowaki, Takashi; Hiraoka, Masahiro

    2012-04-01

    Purpose: To investigate the interfractional dose variations for intensity-modulated radiotherapy (RT) combined with breath-hold (BH) at end-exhalation (EE) for pancreatic cancer. Methods and Materials: A total of 10 consecutive patients with pancreatic cancer were enrolled. Each patient was fixed in the supine position on an individualized vacuum pillow with both arms raised. Computed tomography (CT) scans were performed before RT, and three additional scans were performed during the course of chemoradiotherapy using a conventional RT technique. The CT data were acquired under EE-BH conditions (BH-CT) using a visual feedback technique. The intensity-modulated RT plan, which used five 15-MV coplanar ports, was designed on the initial BH-CT set with a prescription dose of 39 Gy at 2.6 Gy/fraction. After rigid image registration between the initial and subsequent BH-CT scans, the dose distributions were recalculated on the subsequent BH-CT images under the same conditions as in planning. Changes in the dose-volume metrics of the gross tumor volume (GTV), clinical target volume (CTV = GTV + 5 mm), stomach, and duodenum were evaluated. Results: For the GTV and clinical target volume (CTV), the 95th percentile of the interfractional variations in the maximal dose, mean dose, dose covering 95% volume of the region of structure, and percentage of the volume covered by the 90% isodose line were within {+-}3%. Although the volume covered by the 39 Gy isodose line for the stomach and duodenum did not exceed 0.1 mL at planning, the volume covered by the 39 Gy isodose line for these structures was up to 11.4 cm{sup 3} and 1.8 cm{sup 3}, respectively. Conclusions: Despite variations in the gastrointestinal state and abdominal wall position at EE, the GTV and CTV were mostly ensured at the planned dose, with the exception of 1 patient. Compared with the duodenum, large variations in the stomach volume receiving high-dose radiation were observed, which might be beyond the

  4. Treatment and prognosis of patients with late rectal bleeding after intensity-modulated radiation therapy for prostate cancer

    PubMed Central

    2012-01-01

    Background Radiation proctitis after intensity-modulated radiation therapy (IMRT) differs from that seen after pelvic irradiation in that this adverse event is a result of high-dose radiation to a very small area in the rectum. We evaluated the results of treatment for hemorrhagic proctitis after IMRT for prostate cancer. Methods Between November 2004 and February 2010, 403 patients with prostate cancer were treated with IMRT at 2 institutions. Among these patients, 64 patients who developed late rectal bleeding were evaluated. Forty patients had received IMRT using a linear accelerator and 24 by tomotherapy. Their median age was 72 years. Each patient was assessed clinically and/or endoscopically. Depending on the severity, steroid suppositories or enemas were administered up to twice daily and Argon plasma coagulation (APC) was performed up to 3 times. Response to treatment was evaluated using the Rectal Bleeding Score (RBS), which is the sum of Frequency Score (graded from 1 to 3 by frequency of bleeding) and Amount Score (graded from 1 to 3 by amount of bleeding). Stoppage of bleeding over 3 months was scored as RBS 1. Results The median follow-up period for treatment of rectal bleeding was 35 months (range, 12–69 months). Grade of bleeding was 1 in 31 patients, 2 in 26, and 3 in 7. Nineteen of 45 patients (42%) observed without treatment showed improvement and bleeding stopped in 17 (38%), although mean RBS did not change significantly. Eighteen of 29 patients (62%) treated with steroid suppositories or enemas showed improvement (mean RBS, from 4.1 ± 1.0 to 3.0 ± 1.8, p = 0.003) and bleeding stopped in 9 (31%). One patient treated with steroid enema 0.5-2 times a day for 12 months developed septic shock and died of multiple organ failure. All 12 patients treated with APC showed improvement (mean RBS, 4.7 ± 1.2 to 2.3 ± 1.4, p < 0.001) and bleeding stopped in 5 (42%). Conclusions After adequate periods of observation

  5. The Role of Parental Perceptions of Tic Frequency and Intensity in Predicting Tic-Related Functional Impairment in Youth with Chronic Tic Disorders

    PubMed Central

    Espil, Flint M.; Capriotti, Matthew R.; Conelea, Christine A.; Woods, Douglas W.

    2014-01-01

    Tic severity is composed of several dimensions. Tic frequency and intensity are two such dimensions, but little empirical data exist regarding their relative contributions to functional impairment in those with Chronic Tic Disorders (CTD). The present study examined the relative contributions of these dimensions in predicting tic-related impairment across several psychosocial domains. Using data collected from parents of youth with CTD, multivariate regression analyses revealed that both tic frequency and intensity predicted tic-related impairment in several areas; including family and peer relationships, school interference, and social endeavors, even when controlling for the presence of comorbid anxiety symptoms and Attention Deficit Hyperactivity Disorder diagnostic status. Results showed that tic intensity predicted more variance across more domains than tic frequency. PMID:24395287

  6. The role of parental perceptions of tic frequency and intensity in predicting tic-related functional impairment in youth with chronic tic disorders.

    PubMed

    Espil, Flint M; Capriotti, Matthew R; Conelea, Christine A; Woods, Douglas W

    2014-12-01

    Tic severity is composed of several dimensions. Tic frequency and intensity are two such dimensions, but little empirical data exist regarding their relative contributions to functional impairment in those with chronic tic disorders (CTD). The present study examined the relative contributions of these dimensions in predicting tic-related impairment across several psychosocial domains. Using data collected from parents of youth with CTD, multivariate regression analyses revealed that both tic frequency and intensity predicted tic-related impairment in several areas; including family and peer relationships, school interference, and social endeavors, even when controlling for the presence of comorbid anxiety symptoms and Attention Deficit Hyperactivity Disorder diagnostic status. Results showed that tic intensity predicted more variance across more domains than tic frequency.

  7. [Intensity-modulated radiotherapy for head and neck cancer. Dose constraint for salivary gland and mandible].

    PubMed

    Pointreau, Y; Lizée, T; Bensadoun, R-J; Boisselier, P; Racadot, S; Thariat, J; Graff, P

    2016-10-01

    Intensity-modulated radiation therapy (IMRT) is the gold standard for head and neck irradiation. It allows better protection to the organs at risk such as salivary glands and mandible, and can reduce the frequency of xerostomia, trismus and osteoradionecrosis. At the time of treatment planning, the mean dose to a single parotid gland should be kept below 26Gy, the mean dose to a single submandibular gland below 39Gy, the mean dose to the mandible below 60 to 65Gy and the D2% to a single temporomandibular joint below 65Gy. These dose constraints could be further improved with data extracted from cohorts of patients receiving IMRT exclusively. The dose administered to the target volumes should not be lessened to spare the salivary glands or mandible.

  8. Intensity-modulated radiotherapy, not 3D conformal, is the preferred technique for treating locally advanced lung cancer

    PubMed Central

    Chang, Joe Y.

    2015-01-01

    When used to treat lung cancer, intensity-modulated radiotherapy (IMRT) can deliver higher dose to the targets and spare more critical organs in lung cancer than can 3D conformal radiotherapy (3DCRT). However, tumor-motion management and optimized radiotherapy planning based on four-dimensional computed tomography (4D CT) scanning are crucial to maximize the benefit of IMRT and to eliminate or minimize potential uncertainties. This article summarizes these strategies and reviews published findings supporting the safety and efficacy of IMRT for lung cancer. PMID:25771415

  9. 1.319 μm excited intense 800 nm frequency upconversion emission in Tm3+-doped fluorogermanate glass

    NASA Astrophysics Data System (ADS)

    Gouveia-Neto, A. S.; Vermelho, M. V. D.; Gouveia, E. A.; Bueno, L. A.; Jacinto, C.

    2015-11-01

    Generation of near-infrared light within the first biological optical window via frequency upconversion in Tm3+-doped PbGeO3-PbF2-CdF2 glass excited within the second biological window at 1.319 μm is reported. The upconversion emission at 800 nm is the sole light signal observed in the entire ultraviolet-visible-near-infrared spectral region making it possible obtaining high contrast imaging. The dependence of the 800 nm signal upon the sample temperature was investigated and results showed an increase by a factor of ×2.5 in the 30-280 °C range. Generation of detectable 690 nm for temperatures above 100 °C in addition to the intense 800 nm main signal was also observed. The proposed excitation mechanism for the 800 nm thulium emitting level is assigned to a multiphonon-assisted excitation from the ground-state 3H6 to the 3H5 excited-state level, a rapid relaxation to the 3F4 level and followed by an excited-state absorption of the pump photons mediated by multiphonons connecting the 3F4 level to the 3H4 emitting level.

  10. [Effect of low-intensity 900 MHz frequency electromagnetic radiation on rat liver and blood serum enzyme activities].

    PubMed

    Nersesova, L S; Petrosian, M S; Gazariants, M G; Mkrtchian, Z S; Meliksetian, G O; Pogosian, L G; Akopian, Zh I

    2014-01-01

    The comparative analysis of the rat liver and blood serum creatine kinase, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and purine nucleoside phosphorylase post-radiation activity levels after a total two-hour long single and fractional exposure of the animals to low-intensity 900 MHz frequency electromagnetic field showed that the most sensitive enzymes to the both schedules of radiation are the liver creatine kinase, as well as the blood serum creatine kinase and alkaline phosphatase. According to the comparative analysis of the dynamics of changes in the activity level of the liver and blood serum creatine kinase, alanine aminotransferase, aspartate aminotransferase and purine nucleoside phosphorylase, both single and fractional radiation schedules do not affect the permeability of a hepatocyte cell membrane, but rather cause changes in their energetic metabolism. The correlation analysis of the post-radiation activity level changes of the investigated enzymes did not reveal a clear relationship between them. The dynamics of post-radiation changes in the activity of investigated enzyme levels following a single and short-term fractional schedules of radiation did not differ essentially.

  11. Reducing Production Basis Risk through Rainfall Intensity Frequency (RIF) Indexes: Global Sensitivity Analysis' Implication on Policy Design

    NASA Astrophysics Data System (ADS)

    Muneepeerakul, Chitsomanus; Huffaker, Ray; Munoz-Carpena, Rafael

    2016-04-01

    The weather index insurance promises financial resilience to farmers struck by harsh weather conditions with swift compensation at affordable premium thanks to its minimal adverse selection and moral hazard. Despite these advantages, the very nature of indexing causes the presence of "production basis risk" that the selected weather indexes and their thresholds do not correspond to actual damages. To reduce basis risk without additional data collection cost, we propose the use of rain intensity and frequency as indexes as it could offer better protection at the lower premium by avoiding basis risk-strike trade-off inherent in the total rainfall index. We present empirical evidences and modeling results that even under the similar cumulative rainfall and temperature environment, yield can significantly differ especially for drought sensitive crops. We further show that deriving the trigger level and payoff function from regression between historical yield and total rainfall data may pose significant basis risk owing to their non-unique relationship in the insured range of rainfall. Lastly, we discuss the design of index insurance in terms of contract specifications based on the results from global sensitivity analysis.

  12. The role of fatty acids in anti-inflammatory effects of low-intensity extremely high-frequency electromagnetic radiation.

    PubMed

    Gapeyev, Andrew B; Kulagina, Tatiana P; Aripovsky, Alexander V; Chemeris, Nikolay K

    2011-07-01

    The effects of low-intensity extremely high-frequency electromagnetic radiation (EHF EMR; 42.2 GHz, 0.1 mW/cm(2) , exposure duration 20 min) on the fatty acid (FA) composition of thymic cells and blood plasma in normal mice and in mice with peritoneal inflammation were studied. It was found that the exposure of normal mice to EHF EMR increased the content of polyunsaturated FAs (PUFAs) (eicosapentaenoic and docosapentaenoic) in thymic cells. Using a model of zymosan-induced peritoneal inflammation, it was shown that the exposure of mice to EHF EMR significantly increased the content of PUFAs (dihomo-γ-linolenic, arachidonic, eicosapentaenoic, docosapentaenoic, and docosahexaenoic) and reduced the content of monounsaturated FAs (MUFAs) (palmitoleic and oleic) in thymic cells. Changes in the FA composition in the blood plasma were less pronounced and manifested themselves as an increase in the level of saturated FAs during the inflammation. The data obtained support the notion that MUFAs are replaced by PUFAs that can enter into the thymic cells from the external media. Taking into account the fact that the metabolites of PUFAs are lipid messengers actively involved in inflammatory and immune reactions, we assume that the increase in the content of n-3 and n-6 PUFAs in phospholipids of cellular membranes facilitates the realization of anti-inflammatory effects of EHF EMR.

  13. Invited commentary: extremely low-frequency magnetic fields and breast cancer--now it is enough!

    PubMed

    Feychting, Maria

    2013-10-01

    Research on an association between extremely low frequency (ELF) magnetic fields and breast cancer has been conducted since the 1980s, based on the hypothesis that ELF fields suppress melatonin production and melatonin protects against breast cancer development. In this issue of the Journal, Li et al. (Am J Epidemiol. 2013;178(7):1038-1045) present a well-designed study on occupational exposure to ELF fields and breast cancer that adds to the already large pool of data that has not supported the hypothesis. Over time, the quality and statistical power of studies within this research area have increased considerably, and advances in exposure assessment have reduced exposure misclassification. The evidence is consistently negative. A World Health Organization health risk assessment concluded in 2005 that the evidence from experimental and epidemiologic studies is sufficient to give confidence that ELF magnetic fields do not cause breast cancer. The new study adds even more confidence to this conclusion. We should now focus our time and research resources on more promising hypotheses, the results of which could make a difference for public health and advance science. Further epidemiologic studies on ELF fields and breast cancer are likely to have little new knowledge to add. PMID:24043435

  14. Effects of wave function modifications on calculated CF and CCl vibrational frequencies and infrared intensities of the dihaloethylenes

    NASA Astrophysics Data System (ADS)

    Ramos, Mozart N.; da Silva, João Bosco P.; Bruns, Roy E.

    1997-09-01

    The CF and CCl calculated stretching frequencies are shown to obey different factorial models. On average, Møller-Plesset 2 treatment lowers the CF stretching frequencies by 100 cm -1 whereas it only lowers the CCl ones by 37 cm -1. Diffuse functions have negligible effects on these CCl frequencies but lower the CF stretching values by 24 cm -1. However, inclusion of polarization functions in the basis set increases both the CF and CCl stretching frequencies by 90 cm -1. The use of Møller-Plesset 2 treatment also lowers the bending frequencies and the inclusion of polarization functions increases them, although these effects are smaller than those for the stretching frequencies. The stretching and bending mode fundamental intensities of these dihaloethylenes all follow very different factorial models. Low dimensional principal component projections are shown to provide accurate representations of the agreement of the calculated frequencies and intensities with the experimental values. Wave function modifications leading to more accurate characteristic frequency values appear to be relatively insensitive to the vibration's symmetry or the molecular environment of the characteristic CF or CCI groups.

  15. Fruit and Vegetable Dietary Behavior in Response to a Low-Intensity Dietary Intervention: The Rural Physician Cancer Prevention Project

    ERIC Educational Resources Information Center

    Carcaise-Edinboro, Patricia; McClish, Donna; Kracen, Amanda C.; Bowen, Deborah; Fries, Elizabeth

    2008-01-01

    Context: Increased fruit and vegetable intake can reduce cancer risk. Information from this study contributes to research exploring health disparities in high-risk dietary behavior. Purpose: Changes in fruit and vegetable behavior were evaluated to assess the effects of a low-intensity, physician-endorsed dietary intervention in a rural…

  16. Moderate-to-vigorous intensity physical activity across the life course and risk of pre- and post-menopausal breast cancer.

    PubMed

    Kobayashi, Lindsay C; Janssen, Ian; Richardson, Harriet; Lai, Agnes S; Spinelli, John J; Aronson, Kristan J

    2013-06-01

    Moderate-to-vigorous intensity physical activity (MVPA) reduces breast cancer risk, although the effects of MVPA in different settings across the life course and how they may differ by menopausal status are unclear. This gap was addressed using data from a case-control study of 1,110 incident breast cancer cases and 1,172 cancer-free controls, frequency matched by age, from Vancouver and Kingston, Canada. In Vancouver, cases were recruited from the British Columbia Cancer Registry and controls from the Screening Mammography Program of British Columbia and in Kingston cases and controls were recruited from a breast assessment center. Lifetime leisure-time, household, and occupational MVPA energy expenditures were assessed in an open-ended questionnaire and mean weekly metabolic equivalent hours (MET-h/week) were calculated for the age periods 12-17, 18-34, 35-49, and ≥50 years and for the total lifetime. Odds ratios were estimated separately for pre- and for post-menopausal women using unconditional logistic regression. Among post-menopausal women, each of >22.9 MET-h/week of mean lifetime leisure-time MVPA (equivalent to running for 3 h) and >61.1 MET-h/week of mean lifetime household MVPA (equivalent to 24 h of moderate household work) reduced breast cancer risk by 40 %, compared to 0 MET-h/week of each. The respective ORs were 0.63 (95 % CI 0.42-0.94) and 0.58 (95 % CI 0.43-0.79). Among post-menopausal women, leisure-time MVPA after age 35 was more strongly associated with reduced breast cancer risk than MVPA in early life, while household MVPA was associated with reduced risk at all adulthood age periods. The weekly volume of leisure-time MVPA required to reduce post-menopausal breast cancer risk was consistent with amount recommended in the World Cancer Research Fund/American Institute for Cancer Research guidelines for cancer prevention.

  17. Regional Relapse After Intensity-Modulated Radiotherapy for Head-and-Neck Cancer

    SciTech Connect

    Duprez, Frederic; Bonte, Katrien; De Neve, Wilfried; Boterberg, Tom; De Gersem, Werner; Madani, Indira

    2011-02-01

    Purpose: To evaluate the regional relapse rate in the elective neck using intensity-modulated radiotherapy (IMRT) for head-and-neck cancer. Methods and Materials: We retrospectively analyzed the data from 285 patients treated with IMRT between 2000 and 2008. The median dose prescription to the primary tumor and involved lymph nodes was 69 Gy in 32 fractions. The elective neck was treated simultaneously according to Protocol 1 (multiple dose prescription levels of 56-69 Gy; 2-Gy normalized isoeffective dose, 51-70 Gy; 222 patients) or Protocol 2 (one dose prescription level of 56 Gy; 2-Gy normalized isoeffective dose, 51 Gy; 63 patients). Primary surgery or lymph node dissection was performed before IMRT in 72 (25%) and 157 (55%) patients, respectively. Also, 92 patients (32%) received concomitant chemotherapy. The median follow-up of living patients was 27.4 months (range, 0.3-99). Results: Regional, local, and distant relapse were observed in 16 (5.6%), 35 (12.3%), and 47 (16.5%) patients, respectively. The 2- and 5-year rate of regional relapse was 7% and 10%, respectively, with a trend favoring Protocol 2 (p = 0.06). Seven isolated regional relapses were detected at a median follow-up of 7.3 months in patients treated with Protocol 1 and none in those treated with Protocol 2. Percutaneous gastrostomy was required more frequently in patients who received Protocol 1 (p = 0.079). Conclusion: Isolated regional relapse is rare after IMRT for head-and-neck cancer. Elective neck node doses >51 Gy for a 2-Gy normalized isoeffective dose do not seem to improve regional control.

  18. Stereotactic Body Radiation Therapy Versus Intensity-Modulated Radiation Therapy for Prostate Cancer: Comparison of Toxicity

    PubMed Central

    Yu, James B.; Cramer, Laura D.; Herrin, Jeph; Soulos, Pamela R.; Potosky, Arnold L.; Gross, Cary P.

    2014-01-01

    Purpose Stereotactic body radiation therapy (SBRT) is a technically demanding prostate cancer treatment that may be less expensive than intensity-modulated radiation therapy (IMRT). Because SBRT may deliver a greater biologic dose of radiation than IMRT, toxicity could be increased. Studies comparing treatment cost to the Medicare program and toxicity are needed. Methods We performed a retrospective study by using a national sample of Medicare beneficiaries age ≥ 66 years who received SBRT or IMRT as primary treatment for prostate cancer from 2008 to 2011. Each SBRT patient was matched to two IMRT patients with similar follow-up (6, 12, or 24 months). We calculated the cost of radiation therapy treatment to the Medicare program and toxicity as measured by Medicare claims; we used a random effects model to compare genitourinary (GU), GI, and other toxicity between matched patients. Results The study sample consisted of 1,335 SBRT patients matched to 2,670 IMRT patients. The mean treatment cost was $13,645 for SBRT versus $21,023 for IMRT. In the 6 months after treatment initiation, 15.6% of SBRT versus 12.6% of IMRT patients experienced GU toxicity (odds ratio [OR], 1.29; 95% CI, 1.05 to 1.53; P = .009). At 24 months after treatment initiation, 43.9% of SBRT versus 36.3% of IMRT patients had GU toxicity (OR, 1.38; 95% CI, 1.12 to 1.63; P = .001). The increase in GU toxicity was due to claims indicative of urethritis, urinary incontinence, and/or obstruction. Conclusion Although SBRT was associated with lower treatment costs, there appears to be a greater rate of GU toxicity for patients undergoing SBRT compared with IMRT, and prospective correlation with randomized trials is needed. PMID:24616315

  19. Hypofractionated intensity-modulated radiotherapy in patients with localized prostate cancer: a preliminary study

    PubMed Central

    Kang, Hye Jin; Son, Seok Hyun; Kim, Myungsoo; Jo, In Young; Lee, So Jung; Lee, Dong Hwan; Suh, Hong Jin; Choi, Yong Sun

    2016-01-01

    Purpose The aim of this work was to assess the efficacy and tolerability of hypofractionated intensity-modulated radiotherapy (IMRT) in patients with localized prostate cancer. Materials and Methods Thirty-nine patients who received radical hypofractionated IMRT were retrospectively reviewed. Based on a pelvic lymph node involvement risk of 15% as the cutoff value, we decided whether to deliver treatment prostate and seminal vesicle only radiotherapy (PORT) or whole pelvis radiotherapy (WPRT). Sixteen patients (41%) received PORT with prostate receiving 45 Gy in 4.5 Gy per fraction in 2 weeks and the other 23 patients (59%) received WPRT with the prostate receiving 72 Gy in 2.4 Gy per fraction in 6 weeks. The median equivalent dose in 2 Gy fractions to the prostate was 79.9 Gy based on the assumption that the α/β ratio is 1.5 Gy. Results The median follow-up time was 38 months (range, 4 to 101 months). The 3-year biochemical failure-free survival rate was 88.2%. The 3-year clinical failure-free and overall survival rates were 94.5% and 96.3%, respectively. The rates of grade 2 acute genitourinary (GU) and gastrointestinal (GI) toxicities were 20.5% and 12.8%, respectively. None of the patients experienced grade ≥3 acute GU and GI toxicities. The grade 2-3 late GU and GI toxicities were found in 8.1% and 5.4% of patients, respectively. No fatal late toxicity was observed. Conclusion Favorable biochemical control with low rates of toxicity was observed after hypofractionated IMRT, suggesting that our radiotherapy schedule can be an effective treatment option in the treatment of localized prostate cancer. PMID:27104166

  20. Intensity-modulated stereotactic body radiotherapy for stage I non-small cell lung cancer.

    PubMed

    Kim, Min-Jeong; Yeo, Seung-Gu; Kim, Eun Seok; Min, Chul Kee; Se An, Pyung

    2013-03-01

    This study aimed to investigate the clinical outcomes of intensity-modulated radiotherapy (IMRT)-based stereotactic body radiotherapy (SBRT) for patients with stage I non-small cell lung cancer (NSCLC). A prospective database of 16 consecutive patients receiving SBRT for pathologically-proven and peripherally-located stage I NSCLC was reviewed. Fifteen patients were medically inoperable and one patient refused to undergo surgery. The median age of the patients was 76 years (range, 69-86). Treatment planning used four-dimensional computed tomography and fixed-field IMRT (n=11) or volumetric-modulated arc therapy (VMAT; n=5). The SBRT scheme was 48 Gy in four fractions (n=9) or 55 Gy in five fractions (n=7), delivered on consecutive days. The overall response rate at 6 months was 78.6%, including a complete response in three (21.4%) patients and a partial response in eight (57.1%). Three patients (21.4%) demonstrated a stable disease status. The median follow-up time was 14 months (range, 6-20) for the surviving patients. One patient developed local failure at 11 months, while another suffered from regional failure in a subcarinal lymph node at 4 months. Two patients did not survive within the first 6 months; one patient died during salvage chemotherapy for mediastinal lymph node metastasis and the other succumbed to a cause unrelated to lung cancer. The Kaplan-Meier estimates of local failure-free, progression-free and overall survival rates at 18 months were 91.0, 85.2 and 87.5%, respectively. The toxicity was mild; no severe (grade ≥3) toxicity was identified. IMRT-based (including VMAT) delivery of SBRT for patients with stage I NSCLC demonstrated favorable responses and local control without severe toxicity.

  1. Intensity-Modulated Radiotherapy for Cervical Lymph Node Metastases From Unknown Primary Cancer

    SciTech Connect

    Madani, Indira Vakaet, Luc; Bonte, Katrien; Boterberg, Tom; Neve, Wilfried de

    2008-07-15

    Purpose: To compare the effectiveness of intensity-modulated radiotherapy (IMRT) and conventional (two-dimensional) radiotherapy in the treatment of cervical lymph node metastases from unknown primary cancer (UPC). Methods and Materials: Between February 2003 and September 2006, 23 patients with UPC of squamous cell carcinoma were treated with IMRT. Extended putative mucosal and bilateral nodal sites were irradiated to a median dose of 66 Gy. In 19 patients, IMRT was performed after lymph node dissection, and in 4 patients primary radiotherapy was given. The conventional radiotherapy group (historical control group) comprised 18 patients treated to a median dose of 66 Gy between August 1994 and October 2003. Results: Twenty patients completed treatment. As compared with conventional radiotherapy, the incidence of Grade 3 acute dysphagia was significantly lower in the IMRT group (4.5% vs. 50%, p = 0.003). By 6 months, Grade 3 xerostomia was detected in 11.8% patients in the IMRT group vs. 53.4% in the historical control group (p = 0.03). No Grade 3 dysphagia or skin fibrosis was observed after IMRT but these were noted after conventional radiotherapy (26.7%, p = 0.01) and 26.7%, p = 0.03) respectively). With median follow-up of living patients of 17 months, there was no emergence of primary cancer. One patient had persistent nodal disease and another had nodal relapse at 5 months. Distant metastases were detected in 4 patients. The 2-year overall survival and distant disease-free probability after IMRT did not differ significantly from those for conventional radiotherapy (74.8% vs. 61.1% and 76.3% vs. 68.4%, respectively). Conclusions: Use of IMRT for UPC resulted in lower toxicity than conventional radiotherapy, and was similar in efficacy.

  2. The effect of photon energy on intensity-modulated radiation therapy (IMRT) plans for prostate cancer

    PubMed Central

    Sung, Wonmo; Park, Jong Min; Choi, Chang Heon; Ha, Sung Whan

    2012-01-01

    Purpose To evaluate the effect of common three photon energies (6-MV, 10-MV, and 15-MV) on intensity-modulated radiation therapy (IMRT) plans to treat prostate cancer patients. Materials and Methods Twenty patients with prostate cancer treated locally to 81.0 Gy were retrospectively studied. 6-MV, 10-MV, and 15-MV IMRT plans for each patient were generated using suitable planning objectives, dose constraints, and 8-field setting. The plans were analyzed in terms of dose-volume histogram for the target coverage, dose conformity, organs at risk (OAR) sparing, and normal tissue integral dose. Results Regardless of the energies chosen at the plans, the target coverage, conformity, and homogeneity of the plans were similar. However, there was a significant dose increase in rectal wall and femoral heads for 6-MV compared to those for 10-MV and 15-MV. The V20 Gy of rectal wall with 6-MV, 10-MV, and 15-MV were 95.6%, 88.4%, and 89.4% while the mean dose to femoral heads were 31.7, 25.9, and 26.3 Gy, respectively. Integral doses to the normal tissues in higher energy (10-MV and 15-MV) plans were reduced by about 7%. Overall, integral doses in mid and low dose regions in 6-MV plans were increased by up to 13%. Conclusion In this study, 10-MV prostate IMRT plans showed better OAR sparing and less integral doses than the 6-MV. The biological and clinical significance of this finding remains to be determined afterward, considering neutron dose contribution. PMID:23120741

  3. Comparative outcomes for three-dimensional conformal versus intensity-modulated radiation therapy for esophageal cancer.

    PubMed

    Freilich, J; Hoffe, S E; Almhanna, K; Dinwoodie, W; Yue, B; Fulp, W; Meredith, K L; Shridhar, R

    2015-01-01

    Emerging data suggests a benefit for using intensity modulated radiation therapy (IMRT) for the management of esophageal cancer. We retrospectively reviewed patients treated at our institution who received definitive or preoperative chemoradiation with either IMRT or 3D conformal radiation therapy (3DCRT) between October 2000 and January 2012. Kaplan Meier analysis and the Cox proportional hazard model were used to evaluate survival outcomes. We evaluated a total of 232 patients (138 IMRT, 94 3DCRT) who received a median dose of 50.4 Gy (range, 44-64.8) to gross disease. Median follow up for all patients, IMRT patients alone, and 3DCRT patients alone was 18.5 (range, 2.5-124.2), 16.5 (range, 3-59), and 25.9 months (range, 2.5-124.2), respectively. We observed no significant difference based on radiation technique (3DCRT vs. IMRT) with respect to median overall survival (OS) (median 29 vs. 32 months; P = 0.74) or median relapse free survival (median 20 vs. 25 months; P = 0.66). On multivariable analysis (MVA), surgical resection resulted in improved OS (HR 0.444; P < 0.0001). Superior OS was also associated on MVA with stage I/II disease (HR 0.523; P = 0.010) and tumor length ≤5 cm (HR 0.567; P = 0.006). IMRT was also associated on univariate analysis with a significant decrease in acute weight loss (mean 6% + 4.3% vs 9% + 7.4%, P = 0.012) and on MVA with a decrease in objective grade ≥3 toxicity, defined as any hospitalization, feeding tube, or >20% weight loss (OR 0.51; P = 0.050). Our data suggest that while IMRT-based chemoradiation for esophageal cancer does not impact survival there was significantly less toxicity. In the IMRT group there was significant decrease in weight loss and grade ≥3 toxicity compared to 3DCRT.

  4. Intensity-Modulated Radiation Therapy Significantly Improves Acute Gastrointestinal Toxicity in Pancreatic and Ampullary Cancers

    SciTech Connect

    Yovino, Susannah; Poppe, Matthew; Jabbour, Salma; David, Vera; Garofalo, Michael; Pandya, Naimesh; Alexander, Richard; Hanna, Nader; Regine, William F.

    2011-01-01

    Purpose: Among patients with upper abdominal malignancies, intensity-modulated radiation therapy (IMRT) can improve dose distributions to critical dose-limiting structures near the target. Whether these improved dose distributions are associated with decreased toxicity when compared with conventional three-dimensional treatment remains a subject of investigation. Methods and Materials: 46 patients with pancreatic/ampullary cancer were treated with concurrent chemoradiation (CRT) using inverse-planned IMRT. All patients received CRT based on 5-fluorouracil in a schema similar to Radiation Therapy Oncology Group (RTOG) 97-04. Rates of acute gastrointestinal (GI) toxicity for this series of IMRT-treated patients were compared with those from RTOG 97-04, where all patients were treated with three-dimensional conformal techniques. Chi-square analysis was used to determine if there was a statistically different incidence in acute GI toxicity between these two groups of patients. Results: The overall incidence of Grade 3-4 acute GI toxicity was low in patients receiving IMRT-based CRT. When compared with patients who had three-dimensional treatment planning (RTOG 97-04), IMRT significantly reduced the incidence of Grade 3-4 nausea and vomiting (0% vs. 11%, p = 0.024) and diarrhea (3% vs. 18%, p = 0.017). There was no significant difference in the incidence of Grade 3-4 weight loss between the two groups of patients. Conclusions: IMRT is associated with a statistically significant decrease in acute upper and lower GI toxicity among patients treated with CRT for pancreatic/ampullary cancers. Future clinical trials plan to incorporate the use of IMRT, given that it remains a subject of active investigation.

  5. Patterns of Failure and Toxicity after Intensity-Modulated Radiotherapy for Head and Neck Cancer

    SciTech Connect

    Schoenfeld, Gordon O.; Amdur, Robert J.; Morris, Christopher G.; Li, Jonathan G.; Hinerman, Russell W.; Mendenhall, William M.

    2008-06-01

    Purpose: To determine the outcome of patients treated with intensity-modulated radiotherapy (IMRT) for head and neck cancer. Methods and Materials: We reviewed the charts of 100 consecutive patients treated with IMRT for squamous cell carcinoma of the oropharynx (64%), nasopharynx (16%), hypopharynx (14%), and larynx (6%). Most patients were treated with a concomitant boost schedule to 72 Gy. Of the 100 patients, 54 (54%) received adjuvant chemotherapy, mostly concurrent cisplatin. The dosimetry plans for patients with either locoregional failure or Grade 4-5 complications were reviewed and fused over the computed tomography images corresponding with the location of the event. Marginal failures were defined as those that occurred at a region of high-dose falloff, where conventional fields would have provided better coverage. Results: The median follow-up of living patients was 3.1 years (range, 1-5.2 years). The 3-year rate of local control, locoregional control, freedom from relapse, cause-specific survival, and overall survival for all patients was 89%, 87%, 72%, 78%, and 71%, respectively. The 3-year rate of freedom from relapse, cause-specific survival, and overall survival for the 64 oropharynx patients was 86%, 92%, and 84%, respectively. Of the 10 local failures, 2 occurred at the margin of the high-dose planning target volume. Both regional failures occurred within the planning target volume. No locoregional failures occurred outside the planning target volume. Of the 100 patients, 8 and 5 had Grade 4 and 5 complications from treatment, respectively. All patients with Grade 5 complications had received adjuvant chemotherapy. No attempt was made to discriminate between the complications from IMRT and other aspects of the patients' treatment. Conclusion: Intensity-modulated radiotherapy did not compromise the outcome compared with what we have achieved with conventional techniques. The 2 cases of recurrence in the high-dose gradient region highlight the

  6. The Cytotoxic Effects of Low Intensity Visible and Infrared Light on Human Breast Cancer (MCF7) cells.

    PubMed

    Peidaee, P; Almansour, N; Shukla, R; Pirogova, E

    2013-01-01

    A concept of using low intensity light therapy (LILT) as an alternative approach to cancer treatment is at early stages of development; while the therapeutic effects of LILT as a non-invasive treatment modality for localized joint and soft tissue wound healing are widely corroborated. The LEDs-based exposure system was designed and constructed to irradiate the selected cancer and normal cells and evaluate the biological effects induced by light exposures in visible and infrared light range. In this study, human breast cancer (MCF7) cells and human epidermal melanocytes (HEM) cells (control) were exposed to selected far infrared light (3400nm, 3600nm, 3800nm, 3900nm, 4100nm and 4300nm) and visible and near infrared wavelengths (466nm, 585nm, 626nm, 810nm, 850nm and 950nm). The optical intensities of LEDs used for exposures were in the range of 15µW to 30µW. Cellular morphological changes of exposed and sham-exposed cells were evaluated using light microscopy. The cytotoxic effects of these low intensity light exposures on human cancer and normal cell lines were quantitatively determined by Lactate dehydrogenase (LDH) cytotoxic activity and PrestoBlue™ cell viability assays. Findings reveal that far-infrared exposures were able to reduce cell viability of MCF7 cells as measured by increased LDH release activity and PrestoBlue™ assays. Further investigation of the effects of light irradiation on different types of cancer cells, study of possible signaling pathways affected by electromagnetic radiation (EMR) and in vivo experimentation are required in order to draw a firm conclusion about the efficacy of low intensity light as an alternative non-invasive cancer treatment.

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

    SciTech Connect

    Merckel, Laura G.; Bartels, Lambertus W.; Koehler, Max O.; Bongard, H. J. G. Desiree van den; Deckers, Roel; Mali, Willem P. Th. M.; Binkert, Christoph A.; Moonen, Chrit T.; Gilhuijs, Kenneth G. A. Bosch, Maurice A. A. J. van den

    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.

  8. Acinetobacter infections prevalence and frequency of the antibiotics resistance: comparative study of intensive care units versus other hospital units

    PubMed Central

    Uwingabiye, Jean; Frikh, Mohammed; Lemnouer, Abdelhay; Bssaibis, Fatna; Belefquih, Bouchra; Maleb, Adil; Dahraoui, Souhail; Belyamani, Lahcen; Bait, Abdelouahed; Haimeur, Charki; Louzi, Lhoussain; Ibrahimi, Azeddine; Elouennass, Mostafa

    2016-01-01

    Introduction This study aims to determine the Acinetobacter sp clinical isolates frequency and its antibiotic susceptibility pattern by comparing results obtained from the Intensive Care Units (ICUs) to that of other units at the Mohammed V Military Teaching Hospital in Rabat. Methods This is a retrospective study over a 2-years period where we collected all clinical isolates of Acinetobacter sp obtained from samples for infection diagnosis performed on hospitalized patients between 2012 to 2014. Results During the study period, 441 clinical and non-repetitive isolates of Acinetobacter sp were collected representing 6.94% of all bacterial clinical isolates (n = 6352) and 9.6% of Gram negative rods (n = 4569). More than a half of the isolates were from the ICUs and were obtained from 293 infected patients of which 65, 2% (191 cases) were males (sex ratio = 1.9) and the median age was 56 years (interquartile range: 42-68 years). Acinetobacter clinical isolates were obtained from respiratory samples (44.67%) followed by blood cultures (14.51%). The resistance to ciprofloxacin, ceftazidime, piperacillin / tazobactam, imipenem, amikacin, tobramycin, netilmicin, rifampicin and colistin was respectively 87%, 86%, 79%, 76%; 52%, 43%, 33% 32% and 1.7%. The difference in resistance between the ICUs and the other units was statistically significant (p <0.05) except for colistin, tetracycline and rifampicin. Conclusion This paper shows that solving the problem of prevalence and high rate of multidrug resistant Acinetobacter infection which represents a therapeutic impasse, requires the control of the hospital environment and optimizing hands hygiene and antibiotics use in the hospital. PMID:27347280

  9. Extended field intensity-modulated radiotherapy plus concurrent nedaplatin treatment in cervical cancer

    PubMed Central

    LIU, YUNQIN; YU, JINMING; QIAN, LITING; ZHANG, HONGYAN; MA, JUN

    2016-01-01

    The present study assessed the efficacy and toxicity of definitive extended-field intensity-modulated radiotherapy (EF-IMRT) plus concurrent chemotherapy in cervical cancer. A total of 48 patients with cervical cancer received the planning target volume between 39.6 and 50.4 Gy in 1.8–2.0 Gy daily fractions, while the enlarged pelvic and/or para-aortic nodes were treated with a total dose of 55–60 Gy in 2.0–2.4 Gy daily fractions using simultaneous integrated boost-IMRT. All patients underwent high dose-rate brachytherapy. Concurrent to EF-IMRT, nedaplatin was administered weekly at a median dose of 30 mg/m2 (range, 25–40 mg/m2) for 5 weeks with a total of 150 mg/m2. Of the 48 patients, 46 patients exhibited initial complete responses and 2 patients had partial responses, with a response rate of 100%. After 4–24 months of treatment, 12 patients (27.08%) had local and/or distant failure and 39 patients (81.25%) were alive at the last follow-up. The 12-month overall survival (OS) and disease-free survival (DFS) were 87.5 and 75.8%, respectively, while the 24-month OS and DFS were 69.7 and 49.7%, respectively. Grade ≥3 acute neutropenia and thrombcytopenia occurred in 20 (41.7%) and 4 (8.3%) patients, respectively, while 2 patients (4.2%) developed grade ≥3 diarrhea and 2 (4.2%) had grade ≥3 late toxicities. However, no patients exhibited grade ≥3 vomiting. Thus, concurrent nedaplatin chemotherapy with definitive EF-IMRT was effective and relatively safe for treating patients with cervical cancer. Furthermore, EF-IMRT was able to deliver ≤60 Gy to enlarged para-aortic and/or pelvic nodes using simultaneous integrated boost without increased acute and late gastrointestinal toxicity. PMID:27123128

  10. Ab initio calculations of vibrational frequencies and infrared intensities for global warning potential of CFC substitutes. CF{sub 3}CH{sub 2}F (HFC-134a)

    SciTech Connect

    Papasavva, S.; Tai, S.; Esslinger, A.; Illinger, K.H.; Kenny, J.E.

    1995-03-16

    We have investigated the feasibility of using ab initio molecular orbital methods for predicting the global warming potential of the proposed chlorofluorocarbon (CFC) substitute CF{sub 3}CH{sub 2}F, HFC-134a. Various levels of theory and basis sets were used to optimize geometry and calculate harmonic vibrational frequencies and infrared intensities for the molecule using the GAUSSIAN 92 software package. In attempting to assess the quality of the computations, we found it necessary to reconsider the vibrational assignments available in the literature. On the basis of the current assignment, we find that for the highest level calculation, MP2/6-31G{sup **}, the calculated harmonic frequencies agree extremely well with the experimentally observed ones at frequencies below 800 cm{sup {minus}1}, with a systematic error toward higher calculated frequencies becoming apparent above 800 cm{sup {minus}1}. At lower levels of theory, the systematic error is apparent at all frequencies. The regularity of the deviation between calculated and observed frequencies makes ab initio calculations of vibrational frequencies much more useful than semiempirical calculations, which tend to show random deviations, as demonstrated with a PM3-UHF calculation in this work. The calculated absolute intensities are in good agreement with the limited experimental measurements previously reported. 23 refs., 3 figs., 5 tabs.

  11. A 3-week multimodal intervention involving high-intensity interval training in female cancer survivors: a randomized controlled trial.

    PubMed

    Schmitt, Joachim; Lindner, Nathalie; Reuss-Borst, Monika; Holmberg, Hans-Christer; Sperlich, Billy

    2016-02-01

    To compare the effects of a 3-week multimodal rehabilitation involving supervised high-intensity interval training (HIIT) on female breast cancer survivors with respect to key variables of aerobic fitness, body composition, energy expenditure, cancer-related fatigue, and quality of life to those of a standard multimodal rehabilitation program. A randomized controlled trial design was administered. Twenty-eight women, who had been treated for cancer were randomly assigned to either a group performing exercise of low-to-moderate intensity (LMIE; n = 14) or a group performing high-intensity interval training (HIIT; n = 14) as part of a 3-week multimodal rehabilitation program. No adverse events related to the exercise were reported. Work economy improved following both HIIT and LMIE, with improved peak oxygen uptake following LMIE. HIIT reduced mean total body fat mass with no change in body mass, muscle or fat-free mass (best P < 0.06). LMIE increased muscle and total fat-free body mass. Total energy expenditure (P = 0.45) did not change between the groups, whereas both improved quality of life to a similar high extent and lessened cancer-related fatigue. This randomized controlled study demonstrates that HIIT can be performed by female cancer survivors without adverse health effects. Here, HIIT and LMIE both improved work economy, quality of life and cancer-related fatigue, body composition or energy expenditure. Since the outcomes were similar, but HIIT takes less time, this may be a time-efficient strategy for improving certain aspects of the health of female cancer survivors.

  12. A 3-week multimodal intervention involving high-intensity interval training in female cancer survivors: a randomized controlled trial.

    PubMed

    Schmitt, Joachim; Lindner, Nathalie; Reuss-Borst, Monika; Holmberg, Hans-Christer; Sperlich, Billy

    2016-02-01

    To compare the effects of a 3-week multimodal rehabilitation involving supervised high-intensity interval training (HIIT) on female breast cancer survivors with respect to key variables of aerobic fitness, body composition, energy expenditure, cancer-related fatigue, and quality of life to those of a standard multimodal rehabilitation program. A randomized controlled trial design was administered. Twenty-eight women, who had been treated for cancer were randomly assigned to either a group performing exercise of low-to-moderate intensity (LMIE; n = 14) or a group performing high-intensity interval training (HIIT; n = 14) as part of a 3-week multimodal rehabilitation program. No adverse events related to the exercise were reported. Work economy improved following both HIIT and LMIE, with improved peak oxygen uptake following LMIE. HIIT reduced mean total body fat mass with no change in body mass, muscle or fat-free mass (best P < 0.06). LMIE increased muscle and total fat-free body mass. Total energy expenditure (P = 0.45) did not change between the groups, whereas both improved quality of life to a similar high extent and lessened cancer-related fatigue. This randomized controlled study demonstrates that HIIT can be performed by female cancer survivors without adverse health effects. Here, HIIT and LMIE both improved work economy, quality of life and cancer-related fatigue, body composition or energy expenditure. Since the outcomes were similar, but HIIT takes less time, this may be a time-efficient strategy for improving certain aspects of the health of female cancer survivors. PMID:26869680

  13. THE FREQUENCY OF RISK FACTORS ON TRENDS OF PANCREATIC CANCER IN KOSOVO

    PubMed Central

    Ramadani, Naser; Dedushi, Kreshnike; Muçaj, Sefedin; Kabashi, Serbeze; Jerliu, Naim; Hoxhaj, Astrit

    2016-01-01

    The aim: The aim of this paper is to analyze different factors that influence the trends of pancreatic cancer mortality and morbidity of patients treated at the UCCK of Kosovo. Within this study, we have evaluated pancreatic cancer risk factors, durability and lethality regarding Kosovan patients who have been diagnosed and treated within Kosovo. The study in question is that of retrospective research traversing the period of 2011-2015. Materials and methodology: This retrospective research study includes 362 patients recently diagnosed with pancreatic cancer, 2011-2015 at the University Clinical Center of Kosovo in Pristina. The main important factors included in this study are: age, sex and risk factors that altogether have considerable influence in incidence of pancreatic cancer. The imaging diagnostics are performed with the use of 2D ECHO Phillips, MSCT Sensation 64 and 6 and 1.5T MRI Symphony Siemens that are situated in the Radiologic Clinic of UCCK. The statistic data were obtained from NIPH of Kosovo and Agency of Statistics of Kosovo. Results: Out of the total number of the 362 patients diagnosed with pancreatic cancer, the mortality in all age groups was higher at male patients–61.6 % of cases (n=223) with the highest number found at 51–60 years age group. The 38.4 % (n= 139) were female patients with the highest incidence frequency at F 61–70 years age group. The F/M ratio is 1:1.6. The “plane” nicotine users were found at 34 % (n=123) while the joined, nicotine/alcohol addiction was detected at 26 % (n= 94). The 18.5% (n=67) have had established diagnose of the diabetes mellitus tip II and 9.6 % (n=35) have undergone the medical treatment of the gastroduodenal peptic ulcerations. The total number of deaths is 310 (85.6%) and there are only 52 patients (14.4%) still alive. The mortality rate of the pancreatic cancer in Kosovo was 17.2 in 100.000 residents while the morbidity rate was 2.8 in 100.000 residents. Discussion and conclusion: This

  14. Effects of terahertz irradiation at nitric oxide frequencies on intensity of lipoperoxidation and antioxidant properties of the blood under stress conditions.

    PubMed

    Kirichuk, V F; Tsymbal, A A

    2009-08-01

    The effects of terahertz irradiation at the nitric oxide frequencies (150.176-150.664 GHz) on the intensity of lipoperoxidation and antioxidant properties of the blood were examined on albino rats subjected to immobilization stress. This terahertz irradiation completely normalized LPO processes and functional activity of antioxidants in stressed rats. PMID:20027328

  15. Low-Frequency Repetitive Transcranial Magnetic Stimulation and Intensive Occupational Therapy for Poststroke Patients with Upper Limb Hemiparesis: Preliminary Study of a 15-Day Protocol

    ERIC Educational Resources Information Center

    Kakuda, Wataru; Abo, Masahiro; Kobayashi, Kazushige; Momosaki, Ryo; Yokoi, Aki; Fukuda, Akiko; Ishikawa, Atsushi; Ito, Hiroshi; Tominaga, Ayumi

    2010-01-01

    The purpose of the study was to determine the safety and feasibility of a 15-day protocol of low-frequency repetitive transcranial magnetic stimulation (rTMS) combined with intensive occupational therapy (OT) on motor function and spasticity in hemiparetic upper limbs in poststroke patients. Fifteen poststroke patients (age at study entry 55 [plus…

  16. Suitability of frequency modulated thermal wave imaging for skin cancer detection-A theoretical prediction.

    PubMed

    Bhowmik, Arka; Repaka, Ramjee; Mulaveesala, Ravibabu; Mishra, Subhash C

    2015-07-01

    A theoretical study on the quantification of surface thermal response of cancerous human skin using the frequency modulated thermal wave imaging (FMTWI) technique has been presented in this article. For the first time, the use of the FMTWI technique for the detection and the differentiation of skin cancer has been demonstrated in this article. A three dimensional multilayered skin has been considered with the counter-current blood vessels in individual skin layers along with different stages of cancerous lesions based on geometrical, thermal and physical parameters available in the literature. Transient surface thermal responses of melanoma during FMTWI of skin cancer have been obtained by integrating the heat transfer model for biological tissue along with the flow model for blood vessels. It has been observed from the numerical results that, flow of blood in the subsurface region leads to a substantial alteration on the surface thermal response of the human skin. The alteration due to blood flow further causes a reduction in the performance of the thermal imaging technique during the thermal evaluation of earliest melanoma stages (small volume) compared to relatively large volume. Based on theoretical study, it has been predicted that the method is suitable for detection and differentiation of melanoma with comparatively large volume than the earliest development stages (small volume). The study has also performed phase based image analysis of the raw thermograms to resolve the different stages of melanoma volume. The phase images have been found to be clearly individuate the different development stages of melanoma compared to raw thermograms.

  17. High frequency of tumor cells with nuclear Egr-1 protein expression in human bladder cancer is associated with disease progression

    PubMed Central

    2009-01-01

    Background Egr-1 (early growth response-1 transcription factor) has been proposed to be involved in invasion and metastasis processes of human bladder cancer, but Egr-1 protein expression levels in human bladder cancer have not been investigated. In the present study we investigated the expression levels of Egr-1 protein in early stages of human bladder cancer and correlated it to later progression. Methods Expression of Egr-1 protein in human bladder cancer was examined by immunohistochemistry, on a tissue microarray constructed from tumors from 289 patients with non-muscle invasive urothelial bladder cancer. Results The frequency of tumor cells with nuclear Egr-1 immunolabelling correlated to bladder cancer stage, grade and to later progression to muscle-invasive bladder cancer (T2-4). Stage T1 tumors exhibited significantly higher frequencies of tumor cells with nuclear Egr-1 immunolabelling than Ta tumors (P = 0.001). Furthermore, Kaplan-Meier survival analysis showed that a high frequency of tumor cells with nuclear Egr-1 immunolabelling was significantly associated with a higher risk of progression to stage T2-4 (log-rank test, P = 0.035). Tumor cells with nuclear Egr-1 immunolabelling were found to localize at the tumor front in some of the tumor biopsies. Conclusion The results from this study support a potential involvement of Egr-1 in the progression from non-muscle invasive bladder cancers to muscle invasive bladder cancer. PMID:19878561

  18. Intensity-Modulated Radiotherapy in Postoperative Treatment of Oral Cavity Cancers

    SciTech Connect

    Gomez, Daniel R. Zhung, Joanne E.; Gomez, Jennifer; Chan, Kelvin; Wu, Abraham J.; Wolden, Suzanne L.; Pfister, David G.; Shaha, Ashok; Shah, Jatin P.; Kraus, Dennis H.; Wong, Richard J.; Lee, Nancy Y.

    2009-03-15

    Purpose: To present our single-institution experience of intensity-modulated radiotherapy (IMRT) for oral cavity cancer. Methods and Materials: Between September 2000 and December 2006, 35 patients with histologically confirmed squamous cell carcinoma of the oral cavity underwent surgery followed by postoperative IMRT. The sites included were buccal mucosa in 8, oral tongue in 11, floor of the mouth in 9, gingiva in 4, hard palate in 2, and retromolar trigone in 1. Most patients had Stage III-IV disease (80%). Ten patients (29%) also received concurrent postoperative chemotherapy with IMRT. The median prescribed radiation dose was 60 Gy. Results: The median follow-up for surviving patients was 28.1 months (range, 11.9-85.1). Treatment failure occurred in 11 cases as follows: local in 4, regional in 2, and distant metastases in 5. Of the 5 patients with distant metastases, 2 presented with dermal metastases. The 2- and 3-year estimates of locoregional progression-free survival, distant metastasis-free survival, disease-free survival, and overall survival were 84% and 77%, 85% and 85%, 70% and 64%, and 74% and 74%, respectively. Acute Grade 2 or greater dermatitis, mucositis, and esophageal reactions were experienced by 54%, 66%, and 40% of the patients, respectively. Documented late complications included trismus (17%) and osteoradionecrosis (5%). Conclusion: IMRT as an adjuvant treatment after surgical resection for oral cavity tumors is feasible and effective, with promising results and acceptable toxicity.

  19. Intensity-modulated radiation therapy for the treatment of nonanaplastic thyroid cancer

    SciTech Connect

    Rosenbluth, Benjamin D.; Serrano, Victoria B.S.; Happersett, Laura; Shaha, Ashok R.; Tuttle, R. Michael; Narayana, Ashwatha; Wolden, Suzanne L.; Rosenzweig, Kenneth E.; Chong, Lanceford M.; Lee, Nancy Y. . E-mail: leen2@mskcc.org

    2005-12-01

    Purpose: Intensity-modulated radiation therapy (IMRT) enables highly conformal treatment for thyroid cancer (TC). In this study, we review outcomes/toxicity in a series of TC patients treated with IMRT. Methods and Materials: Between July 2001 and January 2004, 20 nonanaplastic TC patients underwent IMRT. Mean age was 55. There were 3 T2 and 17 T4 patients. Sixteen patients had N1 disease. Seven patients had metastases before RT. Fifteen underwent surgery before RT. Radioactive iodine (RAI) and chemotherapy were used in 70% and 40%, respectively. Median total RT dose was 63 Gy. Results: With two local failures, 2-year local progression-free rate was 85%. There were six deaths, with a 2-year overall survival rate of 60%. For patients with M0 disease, the 2-year distant metastases-free rate was 46%. The worst acute mucositis and pharyngitis was Grade 3 (n = 7 and 3, respectively). Two patients had Grade 3 acute skin toxicity and 2 had Grade 3 acute laryngeal toxicity. No significant radiation-related late effects were reported. Conclusions: IMRT for TC is feasible and effective in appropriately selected cases. Acute toxicity is manageable with proactive clinical care. Ideal planning target volume doses have yet to be determined. Additional patients and long-term follow-up are needed to confirm these preliminary findings and to clarify late toxicities.

  20. Salvage High-intensity Focused Ultrasound for the Recurrent Prostate Cancer after Radiotherapy

    SciTech Connect

    Shoji, S.; Nakano, M.; Omata, T.; Harano, Y.; Nagata, Y.; Uchida, T.; Usui, Y.; Terachi, T.

    2010-03-09

    To investigate the use of minimally invasive high-intensity focused ultrasound (HIFU) as a salvage therapy in men with localized prostate cancer recurrence following external beam radiotherapy (EBRT), brachytherapy or proton therapy. A review of 20 cases treated using the Sonablate registered 500 HIFU device, between August 28, 2002 and September 1, 2009, was carried out. All men had presumed organ-confined, histologically confirmed recurrent prostate adenocarcinoma following radiation therapy. All men with presumed, organ-confined, recurrent disease following EBRT in 8 patients, brachytherapy in 7 patients or proton therapy in 5 patients treated with salvage HIFU were included. The patients were followed for a mean (range) of 16.0 (3-80) months. Biochemical disease-free survival (bDFS) rates in patients with low-intermediate and high risk groups were 86% and 50%, respectively. Side-effects included urethral stricture in 2 of the 16 patients (13%), urinary tract infection or dysuria syndrome in eight (26%), and urinary incontinence in one (6%). Recto-urethral fistula occurred in one patient (6%). Transrectal HIFU is an effective treatment for recurrence after radiotherapy especially in patients with low- and intermediate risk groups.

  1. Salvage High-intensity Focused Ultrasound for the Recurrent Prostate Cancer after Radiotherapy

    NASA Astrophysics Data System (ADS)

    Shoji, S.; Nakano, M.; Omata, T.; Harano, Y.; Nagata, Y.; Usui, Y.; Terachi, T.; Uchida, T.

    2010-03-01

    To investigate the use of minimally invasive high-intensity focused ultrasound (HIFU) as a salvage therapy in men with localized prostate cancer recurrence following external beam radiotherapy (EBRT), brachytherapy or proton therapy. A review of 20 cases treated using the Sonablate® 500 HIFU device, between August 28, 2002 and September 1, 2009, was carried out. All men had presumed organ-confined, histologically confirmed recurrent prostate adenocarcinoma following radiation therapy. All men with presumed, organ-confined, recurrent disease following EBRT in 8 patients, brachytherapy in 7 patients or proton therapy in 5 patients treated with salvage HIFU were included. The patients were followed for a mean (range) of 16.0 (3-80) months. Biochemical disease-free survival (bDFS) rates in patients with low-intermediate and high risk groups were 86% and 50%, respectively. Side-effects included urethral stricture in 2 of the 16 patients (13%), urinary tract infection or dysuria syndrome in eight (26%), and urinary incontinence in one (6%). Recto-urethral fistula occurred in one patient (6%). Transrectal HIFU is an effective treatment for recurrence after radiotherapy especially in patients with low- and intermediate risk groups.

  2. Association of Early Patient-Physician Care Planning Discussions and End-of-Life Care Intensity in Advanced Cancer

    PubMed Central

    Tisnado, Diana M.; Walling, Anne M.; Dy, Sydney M.; Asch, Steven M.; Ettner, Susan L.; Kim, Benjamin; Pantoja, Philip; Schreibeis-Baum, Hannah C.; Lorenz, Karl A.

    2015-01-01

    Abstract Background: Early patient-physician care planning discussions may influence the intensity of end-of-life (EOL) care received by veterans with advanced cancer. Objective: The study objective was to evaluate the association between medical record documentation of patient-physician care planning discussions and intensity of EOL care among veterans with advanced cancer. Methods: This was a retrospective cohort study. Subjects were 665 veteran decedents diagnosed with stage IV colorectal, lung, or pancreatic cancer in 2008, and followed till death or the end of the study period in 2011. We estimated the effect of patient-physician care planning discussions documented within one month of metastatic diagnosis on the intensity of EOL care measured by receipt of acute care, intensive interventions, chemotherapy, and hospice care, using multivariate logistic regression models. Results: Veterans in our study were predominantly male (97.1%), white (74.7%), with an average age at diagnosis of 66.4 years. Approximately 31% received some acute care, 9.3% received some intensive intervention, and 6.5% had a new chemotherapy regimen initiated in the last month of life. Approximately 41% of decedents received no hospice or were admitted within three days of death. Almost half (46.8%) had documentation of a care planning discussion within the first month after diagnosis and those who did were significantly less likely to receive acute care at EOL (OR: 0.67; p=0.025). Documented discussions were not significantly associated with intensive interventions, chemotherapy, or hospice care. Conclusion: Early care planning discussions are associated with lower rates of acute care use at the EOL in a system with already low rates of intensive EOL care. PMID:26186553

  3. A Study of the Frequency and Social Determinants of Exposure to Cancer-Related Direct-to-Consumer Advertising Among Breast, Prostate, and Colorectal Cancer Patients.

    PubMed

    Tan, Andy S L

    2015-01-01

    Cancer-related direct-to-consumer advertising (DTCA) is controversial because cancer treatment is complex and entails more risks and costs than typical treatments that are advertised for other conditions. Drawing from the Structural Influence Model of Communication, this study explores communication inequalities in DTCA exposure across social determinants among a population-based sample of 2013 patients diagnosed with breast, prostate, or colorectal cancers. Three survey items assessed patients' frequency of encountering ads concerning treatment alternatives for cancer, dealing with side effects of treatment, and doctors or hospitals offering services for cancer following their diagnosis. The analysis showed that overall exposure to DTCA in this study population was modest (median was once per week). Breast cancer patients reported significantly higher exposure to all three ad categories and overall DTCA exposure than prostate and colorectal cancer patients. Older patients consistently reported lower overall exposure to DTCA across the three cancer types. Other significant correlates included ethnicity (higher exposures among African American prostate cancer patients vs. White; lower exposures in Hispanic colorectal cancer patients vs. White) and cancer stage (higher exposures in Stage IV prostate cancer patients vs. Stages 0-II). Education level did not predict patients' DTCA exposure. The implications of these observed inequalities in DTCA exposure on cancer outcomes are discussed. PMID:25357119

  4. A Study of the Frequency and Social Determinants of Exposure to Cancer-Related Direct-to-Consumer Advertising Among Breast, Prostate, and Colorectal Cancer Patients.

    PubMed

    Tan, Andy S L

    2015-01-01

    Cancer-related direct-to-consumer advertising (DTCA) is controversial because cancer treatment is complex and entails more risks and costs than typical treatments that are advertised for other conditions. Drawing from the Structural Influence Model of Communication, this study explores communication inequalities in DTCA exposure across social determinants among a population-based sample of 2013 patients diagnosed with breast, prostate, or colorectal cancers. Three survey items assessed patients' frequency of encountering ads concerning treatment alternatives for cancer, dealing with side effects of treatment, and doctors or hospitals offering services for cancer following their diagnosis. The analysis showed that overall exposure to DTCA in this study population was modest (median was once per week). Breast cancer patients reported significantly higher exposure to all three ad categories and overall DTCA exposure than prostate and colorectal cancer patients. Older patients consistently reported lower overall exposure to DTCA across the three cancer types. Other significant correlates included ethnicity (higher exposures among African American prostate cancer patients vs. White; lower exposures in Hispanic colorectal cancer patients vs. White) and cancer stage (higher exposures in Stage IV prostate cancer patients vs. Stages 0-II). Education level did not predict patients' DTCA exposure. The implications of these observed inequalities in DTCA exposure on cancer outcomes are discussed.

  5. A Comparison of Helical Intensity-Modulated Radiotherapy, Intensity-Modulated Radiotherapy, and 3D-Conformal Radiation Therapy for Pancreatic Cancer

    SciTech Connect

    Poppe, Matthew M.; Narra, Venkat; Yue, Ning J.; Zhou Jinghao; Nelson, Carl; Jabbour, Salma K.

    2011-01-01

    We assessed dosimetric differences in pancreatic cancer radiotherapy via helical intensity-modulated radiotherapy (HIMRT), linac-based IMRT, and 3D-conformal radiation therapy (3D-CRT) with regard to successful plan acceptance and dose to critical organs. Dosimetric analysis was performed in 16 pancreatic cases that were planned to 54 Gy; both post-pancreaticoduodenectomy (n = 8) and unresected (n = 8) cases were compared. Without volume modification, plans met constraints 75% of the time with HIMRT and IMRT and 13% with 3D-CRT. There was no statistically significantly improvement with HIMRT over conventional IMRT in reducing liver V35, stomach V45, or bowel V45. HIMRT offers improved planning target volume (PTV) dose homogeneity compared with IMRT, averaging a lower maximum dose and higher volume receiving the prescription dose (D100). HIMRT showed an increased mean dose over IMRT to bowel and liver. Both HIMRT and IMRT offer a statistically significant improvement over 3D-CRT in lowering dose to liver, stomach, and bowel. The results were similar for both unresected and resected patients. In pancreatic cancer, HIMRT offers improved dose homogeneity over conventional IMRT and several significant benefits to 3D-CRT. Factors to consider before incorporating IMRT into pancreatic cancer therapy are respiratory motion, dose inhomogeneity, and mean dose.

  6. Dosimetric Evaluation of Different Intensity-Modulated Radiotherapy Techniques for Breast Cancer After Conservative Surgery.

    PubMed

    Zhang, Fuli; Wang, Yadi; Xu, Weidong; Jiang, Huayong; Liu, Qingzhi; Gao, Junmao; Yao, Bo; Hou, Jun; He, Heliang

    2015-10-01

    Intensity-modulated radiotherapy (IMRT) potentially leads to a more favorite dose distribution compared to 3-dimensional or conventional tangential radiotherapy (RT) for breast cancer after conservative surgery or mastectomy. The aim of this study was to compare dosimetric parameters of the planning target volume (PTV) and organs at risk (OARs) among helical tomotherapy (HT), inverse-planned IMRT (IP-IMRT), and forward-planned field in field (FP-FIF) IMRT techniques after breast-conserving surgery. Computed tomography scans from 20 patients (12 left sided and 8 right sided) previously treated with T1N0 carcinoma were selected for this dosimetric planning study. We designed HT, IP-IMRT, and FP-FIF plans for each patient. Plans were compared according to dose-volume histogram analysis in terms of PTV homogeneity and conformity indices (HI and CI) as well as OARs dose and volume parameters. Both HI and CI of the PTV showed statistically significant difference among IP-IMRT, FP-FIF, and HT with those of HT were best (P < .05). Compared to FP-FIF, IP-IMRT showed smaller exposed volumes of ipsilateral lung, heart, contralateral lung, and breast, while HT indicated smaller exposed volumes of ipsilateral lung but larger exposed volumes of contralateral lung and breast as well as heart. In addition, HT demonstrated an increase in exposed volume of ipsilateral lung (except for fraction of lung volume receiving >30 Gy and 20 Gy), heart, contralateral lung, and breast compared with IP-IMRT. For breast cancer radiotherapy (RT) after conservative surgery, HT provides better dose homogeneity and conformity of PTV compared to IP-IMRT and FP-FIF techniques, especially for patients with supraclavicular lymph nodes involved. Meanwhile, HT decreases the OAR volumes receiving higher doses with an increase in the volumes receiving low doses, which is known to lead to an increased rate of radiation-induced secondary malignancies. Hence, composite factors including dosimetric advantage

  7. Time-Frequency Analysis of Peptide Microarray Data: Application to Brain Cancer Immunosignatures

    PubMed Central

    O’Donnell, Brian; Maurer, Alexander; Papandreou-Suppappola, Antonia; Stafford, Phillip

    2015-01-01

    One of the gravest dangers facing cancer patients is an extended symptom-free lull between tumor initiation and the first diagnosis. Detection of tumors is critical for effective intervention. Using the body’s immune system to detect and amplify tumor-specific signals may enable detection of cancer using an inexpensive immunoassay. Immunosignatures are one such assay: they provide a map of antibody interactions with random-sequence peptides. They enable detection of disease-specific patterns using classic train/test methods. However, to date, very little effort has gone into extracting information from the sequence of peptides that interact with disease-specific antibodies. Because it is difficult to represent all possible antigen peptides in a microarray format, we chose to synthesize only 330,000 peptides on a single immunosignature microarray. The 330,000 random-sequence peptides on the microarray represent 83% of all tetramers and 27% of all pentamers, creating an unbiased but substantial gap in the coverage of total sequence space. We therefore chose to examine many relatively short motifs from these random-sequence peptides. Time-variant analysis of recurrent subsequences provided a means to dissect amino acid sequences from the peptides while simultaneously retaining the antibody–peptide binding intensities. We first used a simple experiment in which monoclonal antibodies with known linear epitopes were exposed to these random-sequence peptides, and their binding intensities were used to create our algorithm. We then demonstrated the performance of the proposed algorithm by examining immunosignatures from patients with Glioblastoma multiformae (GBM), an aggressive form of brain cancer. Eight different frameshift targets were identified from the random-sequence peptides using this technique. If immune-reactive antigens can be identified using a relatively simple immune assay, it might enable a diagnostic test with sufficient sensitivity to detect tumors

  8. Effect of varying the intensity and train frequency of forelimb and cerebellar mossy fiber conditioned stimuli on the latency of conditioned eye-blink responses in decerebrate ferrets.

    PubMed

    Svensson, P; Ivarsson, M; Hesslow, G

    1997-01-01

    To study the role of the mossy fiber afferents to the cerebellum in classical eye-blink conditioning, in particular the timing of the conditioned responses, we compared the effects of varying a peripheral conditioned stimulus with the effects of corresponding variations of direct stimulation of the mossy fibers. In one set of experiments, decerebrate ferrets were trained in a Pavlovian eye-blink conditioning paradigm with electrical forelimb train stimulation as conditioned stimulus and electrical periorbital stimulation as the unconditioned stimulus. When stable conditioning had been achieved, the effect of increasing the intensity or frequency of the forelimb stimulation was tested. By increasing the intensity from 1 to 2 mA, or the train frequency from 50 to 100 Hz, an immediate decrease was induced in both the onset latency and the latency to peak of the conditioned response. If the conditioned stimulus intensity/frequency was maintained at the higher level, the response latencies gradually returned to preshift values. In a second set of experiments, the forelimb stimulation was replaced by direct train stimulation of the middle cerebellar peduncle as conditioned stimulus. Varying the frequency of the stimulus train between 50 and 100 Hz had effects that were almost identical to those obtained when using a forelimb conditioned stimulus. The functional meaning of the latency effect is discussed. It is also suggested that the results support the view that the conditioned stimulus is transmitted through the mossy fibers and that the mechanism for timing the conditioned response is situated in the cerebellum.

  9. Dosimetric effects of endorectal balloons on intensity-modulated radiation therapy plans for prostate cancer

    NASA Astrophysics Data System (ADS)

    Kim, Jae-Sung; Chung, Jin-Beom; Kim, In-Ah; Eom, Keun-Yong

    2013-10-01

    We used an endorectal balloon (ERB) for prostate immobilization during intensity-modulated radiotherapy (IMRT) for prostate cancer treatment. To investigate the dosimetric effects of ERB-filling materials, we changed the ERB Hounsfield unit (HU) from 0 to 1000 HU in 200-HU intervals to simulate the various ERB fillings; 0 HU simulated a water-filled ERB, and 1000 HU simulated the densest material-filled ERB. Dosimetric data (coverage, homogeneity, conformity, maximal dose, and typical volume dose) for the tumor and the organs at risk (OARs) were evaluated in prostate IMRT treatment plans with 6-MV and 15-MV beams. The tumor coverage appeared to differ by approximately 1%, except for the clinical target volume (CTV) V100% and the planning target volume (PTV) V100%. The largest difference for the various ERB fillings was observed in the PTV V100%. In spite of increasing HU, the prostate IMRT plans at both energies had relatively low dosimetric effects on the PTV and the CTV. However, the maximal and the typical volume doses (D25%, D30%, and D50%) to the rectal wall and the bladder increased with increasing HU. For an air-filled ERB, the maximal doses to the rectal wall and the monitor units were lower than the corresponding values for the water-filled and the densest material-filled ERBs. An air-filled ERB spared the rectal wall because of its dosimetric effect. Thus, we conclude that the use of an air-filled ERB provides a dosimetric benefit to the rectal wall without a loss of target coverage and is an effective option for prostate IMRT treatment.

  10. Salvage high-intensity focused ultrasound for the recurrent prostate cancer after radiotherapy in Japan

    NASA Astrophysics Data System (ADS)

    Shoji, S.; Nakano, M.; Nagata, Y.; Uchida, T.

    2012-10-01

    Aim: to investigate the use of minimally invasive high-intensity focused ultrasound (HIFU) as a salvage therapy in men with localized prostate cancer recurrence following external beam radiotherapy (EBRT), brachytherapy or proton therapy. A review of 22 cases treated using the Sonablate® 500 HIFU device, between August 28, 2002 and April 1, 2010, was carried out. All men had presumed organ-confined, histologically confirmed recurrent prostate adenocarcinoma following radiation therapy. The mean (range) age was 65 (52-80) years with a mean PSA level before radiation therapy of 14.3 (5.7-118) ng/mL. The mean (range) period after radiation therapy to HIFU was 36 (4-96) months. All men with presumed, organ-confined, recurrent disease following EBRT in 14 patients, brachytherapy in 5 patients (4 patients with high-dose brachytherapy with In192 and 1 with low-dose brachytherapy with Au98) or proton therapy in 3 patients treated with salvage HIFU were included. The patients were followed for a mean (range) of 24 months. Biochemical disease-free survival (bDFS) rates in patients with low-, intermediate-and high risk groups were 100%, 86%, and 14%, respectively. All nine patients who received a post HIFU prostate biopsy showed no malignancy. Side-effects included urethral stricture in 4 of the 25 patients (16%) and urinary incontinence in 4 of the 25 patients (16%). Recto-urethral fistula occurred in one patient (4%). Salvage HIFU is a minimally invasive for patients with low-and intermediate risk group with comparable morbidity to other forms of salvage treatment.

  11. Evaluation of Parotid Gland Function following Intensity Modulated Radiation Therapy for Head and Neck Cancer

    PubMed Central

    Lee, Seok Ho; Kim, Tae Hyun; Kim, Joo Young; Park, Sung Yong; Pyo, Hong Ryull; Shin, Kyung Hwan; Kim, Dae Yong; Kim, Joo Young

    2006-01-01

    Purpose This study was undertaken to determine the parotid gland tolerance dose levels following intensity modulated radiation therapy (IMRT) for treating patients who suffered with head and neck cancer. Materials and Methods From February 2003 through June 2004, 34 head and neck patients with 6 months of follow-up were evaluated for xerostomia after being treated by IMRT. Their median age was 59 years (range: 29~78). Xerostomia was assessed using a 4-question xerostomia questionnaire score (XQS) and a test for the salivary flow rates (unstimulated and stimulated: USFR and SSFR, respectively). The patients were also given a validated LENT SOMA scale (LSS) questionnaire. Evaluations were performed before IMRT and at 1, 3 and 6 months after IMRT. Results All 34 patients showed significant changes in the XQS, LSS and Salivary Flow rates (USFR and SSFR) after IMRT. No significant changes in the XQS or LSS were noted in 12 patients who received a total parotid mean dose of ≤3,100 cGy at 1, 3 and 6 months post-IMRT relative to the baseline values. However, for the 22 patients who received >3,100 cGy, significant increases in the XQS and LSS were observed. The USFR and SSFR from the parotid glands in 7 patients who received ≤2,750 cGy were significantly preserved at up to 6 months after IMRT. However, the USFR and SSFR in 27 patients who were treated with >2,750 cGy were significantly lower than the baseline values at all times after IMRT. Conclusion We suggest that the total parotid mean dose should be limited to ≤2,750 cGy to preserve the USFR and SSFR and so improve the subsequent quality of life. PMID:19771265

  12. Salvage High-intensity Focused Ultrasound for the Recurrent Prostate Cancer after Radiotherapy in Japan

    NASA Astrophysics Data System (ADS)

    Shoji, S.; Nakano, M.; Nagata, Y.; Uchida, T.

    2011-09-01

    To investigate the use of minimally invasive high-intensity focused ultrasound (HIFU) as a salvage therapy in men with localized prostate cancer recurrence following external beam radiotherapy (EBRT), brachytherapy or proton therapy. A review of 20 cases treated using the Sonablate® 500 HIFU device, between August 28, 2002 and June 1, 2010, was carried out. All men had presumed organ-confined, histologically confirmed recurrent prostate adenocarcinoma following radiation therapy. The mean (range) age was 65 (52-80) years with a mean PSA level before radiation therapy of 26.6 (4.8-118) ng/mL. The mean (range) period after radiation therapy to HIFU was 41 (4-96) months. All men with presumed, organ-confined, recurrent disease following EBRT in 13 patients, brachytherapy in 5 patients (4 patients with high-dose brachytherapy with In192 and 1 with low-dose brachytherapy with Au98) or proton therapy in 4 patients treated with salvage HIFU were included. The patients were followed for a mean (range) of 21 months. Biochemical disease-free survival (bDFS) rates in patients with low-, intermediate- and high risk groups were 100%, 85.7%, and 18.2%, respectively. All nine patients who received a post HIFU prostate biopsy showed no malignancy. Side-effects included urethral stricture in 4 of the 22 patients (18%) and urinary incontinence in 4 of the 22 patients (18%). Recto-urethral fistula occurred in one patient (5%). Salvage HIFU is a minimally invasive for patients with low-and intermediate risk group with comparable morbidity to other forms of salvage treatment.

  13. Concurrent Chemotherapy and Intensity-Modulated Radiotherapy for Locoregionally Advanced Laryngeal and Hypopharyngeal Cancers

    SciTech Connect

    Lee, Nancy Y. O'Meara, William; Chan, Kelvin; Della-Bianca, Cesar; Mechalakos, James G.; Zhung, Joanne; Wolden, Suzanne L.; Narayana, Ashwatha; Kraus, Dennis; Shah, Jatin P.; Pfister, David G.

    2007-10-01

    Purpose: To perform a retrospective review of laryngeal/hypopharyngeal carcinomas treated with concurrent chemotherapy and intensity-modulated radiotherapy (IMRT). Methods and Materials: Between January 2002 and June 2005, 20 laryngeal and 11 hypopharyngeal carcinoma patients underwent IMRT with concurrent platinum-based chemotherapy; most patients had Stage IV disease. The prescription of the planning target volume for gross, high-risk, and low-risk subclinical disease was 70, 59.4, and 54 Gy, respectively. Acute/late toxicities were retrospectively scored using the Common Toxicity Criteria scale. The 2-year local progression-free, regional progression-free, laryngectomy-free, distant metastasis-free, and overall survival rates were calculated using the Kaplan-Meier method. Results: The median follow-up of the living patients was 26 months (range, 17-58 months). The 2-year local progression-free, regional progression-free, laryngectomy-free, distant metastasis-free, and overall survival rate was 86%, 94%, 89%, 92%, and 63%, respectively. Grade 2 mucositis or higher occurred in 48% of patients, and all experienced Grade 2 or higher pharyngitis during treatment. Xerostomia continued to decrease over time from the end of RT, with none complaining of Grade 2 toxicity at this analysis. The 2-year post-treatment percutaneous endoscopic gastrostomy-dependency rate for those with hypopharyngeal and laryngeal tumors was 31% and 15%, respectively. The most severe late complications were laryngeal necrosis, necrotizing fascitis, and a carotid rupture resulting in death 3 weeks after salvage laryngectomy. Conclusion: These preliminary results have shown that IMRT achieved encouraging locoregional control of locoregionally advanced laryngeal and hypopharyngeal carcinomas. Xerostomia improved over time. Pharyngoesophageal stricture with percutaneous endoscopic gastrostomy dependency remains a problem, particularly for patients with hypopharyngeal carcinoma and, to a lesser

  14. Intensity-Modulated Proton Therapy Versus Helical Tomotherapy in Nasopharynx Cancer: Planning Comparison and NTCP Evaluation

    SciTech Connect

    Widesott, Lamberto Pierelli, Alessio; Fiorino, Claudio; Dell'Oca, Italo; Broggi, Sara; Cattaneo, Giovanni Mauro; Di Muzio, Nadia; Fazio, Ferruccio; Calandrino, Riccardo; Schwarz, Marco

    2008-10-01

    Purpose: To compare intensity-modulated proton therapy (IMPT) and helical tomotherapy (HT) treatment plans for nasopharynx cancer using a simultaneous integrated boost approach. Methods and Materials: The data from 6 patients who had previously been treated with HT were used. A three-beam IMPT technique was optimized in the Hyperion treatment planning system, simulating a 'beam scanning' technique. HT was planned using the tomotherapy treatment planning system. Both techniques were optimized to simultaneously deliver 66 Gy in 30 fractions to planning target volume (PTV1; GTV and enlarged nodes) and 54 Gy to PTV2 subclinical, electively treated nodes. Normal tissue complication probability calculation was performed for the parotids and larynx. Results: Very similar PTVs coverage and homogeneity of the target dose distribution for IMPT and HT were found. The conformity index was significantly lower for protons than for photons (1.19 vs. 1.42, respectively). The mean dose to the ipsilateral and contralateral parotid glands decreased by 6.4 Gy and 5.6 Gy, respectively, with IMPT. The volume of mucosa and esophagus receiving {>=}20 Gy and {>=}30 Gy with IMPT was significantly lower than with HT. The average volume of larynx receiving {>=}50 Gy was significantly lower with HT, while for thyroid, it was comparable. The volume receiving {>=}30, {>=}20, and {>=}10 Gy in total body volume decreased with IMPT by 14.5%, 19.4%, and 23.1%, respectively. The normal tissue complication probability for the parotid glands was significantly lower with IMPT for all sets of parameters; however, we also estimated an almost full recovery of the contralateral parotid with HT. The normal tissue complication probability for the larynx was not significantly different between the two irradiation techniques. Conclusion: Excellent target coverage, homogeneity within the PTVs, and sparing of the organs at risk were reached with both modalities. IMPT allows for better sparing of most organs at

  15. Retrospective estimate of the quality of intensity-modulated radiotherapy plans for lung cancer

    NASA Astrophysics Data System (ADS)

    Koo, Jihye; Yoon, Myonggeun; Chung, Weon Kuu; Kim, Dong Wook

    2015-07-01

    This study estimated the planning quality of intensity-modulated radiotherapy in 42 lung cancer cases to provide preliminary data for the development of a planning quality assurance algorithm. Organs in or near the thoracic cavity (ipsilateral lung, contralateral lung, heart, liver, esophagus, spinal cord, and bronchus) were selected as organs at risk (OARs). Radiotherapy plans were compared by using the conformity index (CI), coverage index (CVI), and homogeneity index (HI) of the planning target volume (PTV), the OAR-PTV distance and the OAR-PTV overlap volume, and the V10 Gy , V20 Gy , and equivalent uniform dose (EUD) of the OARs. The CI, CVI, and HI of the PTV were 0.54-0.89 (0.77 ± 0.08), 0.90-1.00 (0.98 ± 0.02), and 0.11-0.41, (0.15 ± 0.05), respectively. The mean EUDs (V10 Gy , V20 Gy ) of the ipsilateral lung, contralateral lung, esophagus, cord, liver, heart, and bronchus were 8.07 Gy (28.06, 13.17), 2.59 Gy (6.53, 1.18), 7.02 Gy (26.17, 12.32), 3.56 Gy (13.56, 4.48), 0.72 Gy (2.15, 0.91), 5.14 Gy (19.68, 8.62), and 10.56 Gy (36.08, 19.79), respectively. EUDs tended to decrease as the OAR-PTV distance increased and the OAR-PTV overlap volume decreased. Because the plans in this study were from a single department, relatively few people were involved in treatment planning. Differences in treatment results for a given patient would be much more pronounced if many departments were involved.

  16. Dosimetric comparison of intensity-modulated solutions for intact prostate cancer

    SciTech Connect

    Neill, Cory J.

    2014-01-01

    The purpose of this study is intended to investigate the implementation of a modified class solution for intact prostate intensity-modulated radiation therapy (IMRT). The class solution uses 2 additional optimization structures intended to increase target conformity and decrease unnecessary dose to healthy tissue. A total of 10 randomly selected intact prostate IMRT patients were chosen for this retrospective study. Each of the original IMRT plans was compared with a modified class solution. The class solution implemented 2 additional optimization structures. The 95{sub O}PT was intended to increase target conformity, and the Avoidance{sub 3}780 was intended to reduce normal tissue. Each plan was evaluated for minimum, maximum, and mean doses to the target. Additionally, mean normal tissue dose, total monitor units (MUs), and segments were investigated. Conformity index and normal healthy index were also compared. All comparisons were evaluated using a paired t-test using GraphPad software. Evaluations of MUs; segments; minimum, maximum, mean target doses; mean normal tissue dose; and conformity index did not demonstrate a significant difference between the modified class solution and the original plans. However, evaluation of healthy tissue conformity index indicated a significant difference. Overall, 70% of the original plans failed to demonstrate a satisfactory score (< 0.6) of properly sparing normal healthy tissue, whereas 70% of the modified plans exhibited a satisfactory score (> 0.6). Most (90%) of the modified plans demonstrated a greater number of segments than the compared original plan. A modified class solution provides a good starting point for planning intact prostate cancer. The addition of the Avoidance{sub 3}780 structure increases the healthy tissue conformity index score.

  17. Acute Esophagus Toxicity in Lung Cancer Patients After Intensity Modulated Radiation Therapy and Concurrent Chemotherapy

    SciTech Connect

    Kwint, Margriet; Uyterlinde, Wilma; Nijkamp, Jasper; Chen, Chun; Bois, Josien de; Sonke, Jan-Jakob; Heuvel, Michel van den; Knegjens, Joost; Herk, Marcel van; Belderbos, Jose

    2012-10-01

    Purpose: The purpose of this study was to investigate the dose-effect relation between acute esophageal toxicity (AET) and the dose-volume parameters of the esophagus after intensity modulated radiation therapy (IMRT) and concurrent chemotherapy for patients with non-small cell lung cancer (NSCLC). Patients and Methods: One hundred thirty-nine patients with inoperable NSCLC treated with IMRT and concurrent chemotherapy were prospectively analyzed. The fractionation scheme was 66 Gy in 24 fractions. All patients received concurrently a daily dose of cisplatin (6 mg/m Superscript-Two ). Maximum AET was scored according to Common Toxicity Criteria 3.0. Dose-volume parameters V5 to V70, D{sub mean} and D{sub max} of the esophagus were calculated. A logistic regression analysis was performed to analyze the dose-effect relation between these parameters and grade {>=}2 and grade {>=}3 AET. The outcome was compared with the clinically used esophagus V35 prediction model for grade {>=}2 after radical 3-dimensional conformal radiation therapy (3DCRT) treatment. Results: In our patient group, 9% did not experience AET, and 31% experienced grade 1 AET, 38% grade 2 AET, and 22% grade 3 AET. The incidence of grade 2 and grade 3 AET was not different from that in patients treated with CCRT using 3DCRT. The V50 turned out to be the most significant dosimetric predictor for grade {>=}3 AET (P=.012). The derived V50 model was shown to predict grade {>=}2 AET significantly better than the clinical V35 model (P<.001). Conclusions: For NSCLC patients treated with IMRT and concurrent chemotherapy, the V50 was identified as most accurate predictor of grade {>=}3 AET. There was no difference in the incidence of grade {>=}2 AET between 3DCRT and IMRT in patients treated with concurrent chemoradiation therapy.

  18. Magnetic liposomes for colorectal cancer cells therapy by high-frequency magnetic field treatment

    NASA Astrophysics Data System (ADS)

    Hardiansyah, Andri; Huang, Li-Ying; Yang, Ming-Chien; Liu, Ting-Yu; Tsai, Sung-Chen; Yang, Chih-Yung; Kuo, Chih-Yu; Chan, Tzu-Yi; Zou, Hui-Ming; Lian, Wei-Nan; Lin, Chi-Hung

    2014-09-01

    In this study, we developed the cancer treatment through the combination of chemotherapy and thermotherapy using doxorubicin-loaded magnetic liposomes. The citric acid-coated magnetic nanoparticles (CAMNP, ca. 10 nm) and doxorubicin were encapsulated into the liposome (HSPC/DSPE/cholesterol = 12.5:1:8.25) by rotary evaporation and ultrasonication process. The resultant magnetic liposomes ( ca. 90 to 130 nm) were subject to characterization including transmission electron microscopy (TEM), dynamic light scattering (DLS), X-ray diffraction (XRD), zeta potential, Fourier transform infrared (FTIR) spectrophotometer, and fluorescence microscope. In vitro cytotoxicity of the drug carrier platform was investigated through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay using L-929 cells, as the mammalian cell model. In vitro cytotoxicity and hyperthermia (inductive heating) studies were evaluated against colorectal cancer (CT-26 cells) with high-frequency magnetic field (HFMF) exposure. MTT assay revealed that these drug carriers exhibited no cytotoxicity against L-929 cells, suggesting excellent biocompatibility. When the magnetic liposomes with 1 μM doxorubicin was used to treat CT-26 cells in combination with HFMF exposure, approximately 56% cells were killed and found to be more effective than either hyperthermia or chemotherapy treatment individually. Therefore, these results show that the synergistic effects between chemotherapy (drug-controlled release) and hyperthermia increase the capability to kill cancer cells.

  19. Magnetic liposomes for colorectal cancer cells therapy by high-frequency magnetic field treatment

    PubMed Central

    2014-01-01

    In this study, we developed the cancer treatment through the combination of chemotherapy and thermotherapy using doxorubicin-loaded magnetic liposomes. The citric acid-coated magnetic nanoparticles (CAMNP, ca. 10 nm) and doxorubicin were encapsulated into the liposome (HSPC/DSPE/cholesterol = 12.5:1:8.25) by rotary evaporation and ultrasonication process. The resultant magnetic liposomes (ca. 90 to 130 nm) were subject to characterization including transmission electron microscopy (TEM), dynamic light scattering (DLS), X-ray diffraction (XRD), zeta potential, Fourier transform infrared (FTIR) spectrophotometer, and fluorescence microscope. In vitro cytotoxicity of the drug carrier platform was investigated through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay using L-929 cells, as the mammalian cell model. In vitro cytotoxicity and hyperthermia (inductive heating) studies were evaluated against colorectal cancer (CT-26 cells) with high-frequency magnetic field (HFMF) exposure. MTT assay revealed that these drug carriers exhibited no cytotoxicity against L-929 cells, suggesting excellent biocompatibility. When the magnetic liposomes with 1 μM doxorubicin was used to treat CT-26 cells in combination with HFMF exposure, approximately 56% cells were killed and found to be more effective than either hyperthermia or chemotherapy treatment individually. Therefore, these results show that the synergistic effects between chemotherapy (drug-controlled release) and hyperthermia increase the capability to kill cancer cells. PMID:25246875

  20. Estimates of the gene frequency of BRCA1 and its contribution to breast and ovarian cancer incidence

    SciTech Connect

    Ford, D.; Easton, D.F.; Peto, J.

    1995-12-01

    The majority of multiple-case families that segregate both breast and ovarian cancer in a dominant fashion are due to mutations in the BRCA1 gene on chromosome 17q. In this paper, we have combined penetrance estimates for BRCA1 with the results of two population-based genetic epidemiological studies to estimate the gene frequency of BRCA1. On the assumption that the excess risk of ovarian cancer in first degree relatives of breast cancer patients and the breast cancer excess in relatives of ovarian cancer patients are both entirely accounted for by BRCA1, we estimate that the BRCA1 gene frequency is 0.0006 (95% confidence interval [0.0002-0.001]) and that the proportion of breast cancer cases in the general population due to BRCA1 is 5.3% below age 40 years, 2.2% between ages 40 and 49 years, and 1.1% between ages 50 and 70 years. The corresponding estimates for ovarian cancer are 5.7%, 4.6%, and 2.1%, respectively. Our results suggest that the majority of breast cancer families with less than four cases and no ovarian cancer are not due to rare highly penetrant genes such as BRCA1 but are more likely to be due either to chance or to more common genes of lower penetrance. 22 refs., 3 tabs.

  1. Early and Intensive Dietary Counseling in Lung Cancer Patients Receiving (Chemo)Radiotherapy-A Pilot Randomized Controlled Trial.

    PubMed

    Kiss, Nicole; Isenring, Elisabeth; Gough, Karla; Wheeler, Greg; Wirth, Andrew; Campbell, Belinda A; Krishnasamy, Meinir

    2016-01-01

    Malnutrition is prevalent in patients undergoing (chemo)radiotherapy (RT) for lung cancer. This pilot study tested the feasibility and acceptability of delivering an intensive nutrition intervention for lung cancer patients receiving RT. Twenty-four patients with lung cancer were randomized to receive the intervention which employed a care pathway to guide intensive dietary counseling from pretreatment until 6-wk posttreatment or usual care. Nutritional, fatigue, and functional outcomes were assessed using valid and reliable questionnaires before randomization, at the start and end of RT and 1- and 3-mo post-RT. Consent rate was 57% with an overall attrition of 37%. Subject compliance with the completion of study questionnaires was 100%. A clinically important mean difference indicated greater overall satisfaction with nutritional care in the intervention group (5.00, interquartile range [IQR] 4.50-5.00; 4.00, IQR 4.00-4.00). Clinically important differences favoring the intervention were observed for weight (3.0 kg; 95% confidence interval [CI] -0.8, 6.8), fat-free mass (0.6 kg; 95% CI -2.1, 3.3), physical well-being (2.1; 95% CI -2.3, 6.5), and functional well-being (5.1; 95% CI 1.6, 8.6), but all 95% CIs were wide and most included zero. Recruitment feasibility and acceptability of the intervention were demonstrated, which suggest larger trials using an intensive nutrition intervention would be achievable. PMID:27348253

  2. Simple Carotid-Sparing Intensity-Modulated Radiotherapy Technique and Preliminary Experience for T1-2 Glottic Cancer

    SciTech Connect

    Rosenthal, David I.; Fuller, Clifton D.; Barker, Jerry L.; Mason, Bryan M.S.; Garcia, John A. C.; Lewin, Jan S.; Holsinger, F. Christopher; Stasney, C. Richard; Frank, Steven J.; Schwartz, David L.; Morrison, William H.; Garden, Adam S.; Ang, K. Kian

    2010-06-01

    Purpose: To investigate the dosimetry and feasibility of carotid-sparing intensity-modulated radiotherapy (IMRT) for early glottic cancer and to report preliminary clinical experience. Methods and Materials: Digital Imaging and Communications in Medicine radiotherapy (DICOM-RT) datasets from 6 T1-2 conventionally treated glottic cancer patients were used to create both conventional IMRT plans. We developed a simplified IMRT planning algorithm with three fields and limited segments. Conventional and IMRT plans were compared using generalized equivalent uniform dose and dose-volume parameters for in-field carotid arteries, target volumes, and organs at risk. We have treated 11 patients with this simplified IMRT technique. Results: Intensity-modulated radiotherapy consistently reduced radiation dose to the carotid arteries (p < 0.05) while maintaining the clinical target volume coverage. With conventional planning, median carotid V35, V50, and V63 were 100%, 100%, and 69.0%, respectively. With IMRT planning these decreased to 2%, 0%, and 0%, respectively (p < 0.01). Radiation planning and treatment times were similar for conventional radiotherapy and IMRT. Treatment results have been excellent thus far. Conclusions: Intensity-modulated radiotherapy significantly reduced unnecessary radiation dose to the carotid arteries compared with conventional lateral fields while maintaining clinical target volume coverage. Further experience and longer follow-up will be required to demonstrate outcomes for cancer control and carotid artery effects.

  3. Transmitter release from cochlear hair cells is phase locked to cyclic stimuli of different intensities and frequencies.

    PubMed

    Goutman, Juan D

    2012-11-21

    The auditory system processes time and intensity through separate brainstem pathways to derive spatial location as well as other salient features of sound. The independent coding of time and intensity begins in the cochlea, where afferent neurons can fire action potentials at constant phase throughout a wide range of stimulus intensities. We have investigated time and intensity coding by simultaneous presynaptic and postsynaptic recording at the hair cell-afferent synapse from rats. Trains of depolarizing steps to the hair cell were used to elicit postsynaptic currents that occurred at constant phase for a range of membrane potentials over which release probability varied significantly. To probe the underlying mechanisms, release was examined using single steps to various command voltages. As expected for vesicular release, first synaptic events occurred earlier as presynaptic calcium influx grew larger. However, synaptic depression produced smaller responses with longer first latencies. Thus, during repetitive hair cell stimulation, as the hair cell is more strongly depolarized, increased calcium channel gating hurries transmitter release, but the resulting vesicular depletion produces a compensatory slowing. Quantitative simulation of ribbon function shows that these two factors varied reciprocally with hair cell depolarization (stimulus intensity) to produce constant synaptic phase. Finally, we propose that the observed rapid vesicle replenishment would help maintain the vesicle pool, which in turn would equilibrate with the stimulus intensity (and therefore the number of open Ca(2+) channels), so that for trains of different levels the average phase will be conserved. PMID:23175853

  4. [The frequency of cancer in France: mortality trends since 1950 and summary of the report on the causes of cancer].

    PubMed

    Hill, Catherine; Doyon, Françoise

    2008-01-01

    In 2005, a total number of 149,000 cancer deaths were observed in France, 89,000 in the male population and 60,000 in the female population. Age-standardised mortality rates are decreasing for most cancer sites, at least in recent years, the main exception being lung cancer in the female population which has become the second cause of cancer deaths after breast cancer. The report on the attributable causes of cancer in France from the International Agency for Research on Cancer, the French Science and Medical Academies and the Fédération Nationale des Centres de Lutte Contre le Cancer shows the importance of tobacco alcohol and infections. They are the most important causes of cancer in France, leading respectively to 24 %, 7 % and 4 % of cancer deaths. Cancer prevention is possible as demonstrated by the decrease in tobacco and alcohol consumption in the male population leading to a reduction in the risk of cancer.

  5. Intensity-Modulated Whole Abdominal Radiotherapy After Surgery and Carboplatin/Taxane Chemotherapy for Advanced Ovarian Cancer: Phase I Study

    SciTech Connect

    Rochet, Nathalie; Sterzing, Florian; Jensen, Alexandra D.; Dinkel, Julien; Herfarth, Klaus K.; Schubert, Kai; Eichbaum, Michael H.; Schneeweiss, Andreas; Sohn, Christof; Debus, Juergen; Harms, Wolfgang

    2010-04-15

    Purpose: To assess the feasibility and toxicity of consolidative intensity-modulated whole abdominal radiotherapy (WAR) after surgery and chemotherapy in high-risk patients with advanced ovarian cancer. Methods and Materials: Ten patients with optimally debulked ovarian cancer International Federation of Gynecology and Obstetrics Stage IIIc were treated in a Phase I study with intensity-modulated WAR up to a total dose of 30 Gy in 1.5-Gy fractions as consolidation therapy after adjuvant carboplatin/taxane chemotherapy. Treatment was delivered using intensity-modulated radiotherapy in a step-and-shoot technique (n = 3) or a helical tomotherapy technique (n = 7). The planning target volume included the entire peritoneal cavity and the pelvic and para-aortal node regions. Organs at risk were kidneys, liver, heart, vertebral bodies, and pelvic bones. Results: Intensity-modulated WAR resulted in an excellent coverage of the planning target volume and an effective sparing of the organs at risk. The treatment was well tolerated, and no severe Grade 4 acute side effects occurred. Common Toxicity Criteria Grade III toxicities were as follows: diarrhea (n = 1), thrombocytopenia (n = 1), and leukopenia (n = 3). Radiotherapy could be completed by all the patients without any toxicity-related interruption. Median follow-up was 23 months, and 4 patients had tumor recurrence (intraperitoneal progression, n = 3; hepatic metastasis, n = 1). Small bowel obstruction caused by adhesions occurred in 3 patients. Conclusions: The results of this Phase I study showed for the first time, to our knowledge, the clinical feasibility of intensity-modulated whole abdominal radiotherapy, which could offer a new therapeutic option for consolidation treatment of advanced ovarian carcinoma after adjuvant chemotherapy in selected subgroups of patients. We initiated a Phase II study to further evaluate the toxicity of this intensive multimodal treatment.

  6. A randomised trial of low-dose/high-frequency chemotherapy as palliative treatment of poor-prognosis small-cell lung cancer: a Cancer research Campaign trial.

    PubMed Central

    James, L. E.; Gower, N. H.; Rudd, R. M.; Spiro, S. G.; Harper, P. G.; Trask, C. W.; Partridge, M.; Ruiz de Elvira, M. C.; Souhami, R. L.

    1996-01-01

    We report the results of a randomised trial in extensive small-cell lung cancer (SCLC) of a novel approach to palliative chemotherapy. A widely used 3 weekly regimen was compared with the same drugs given at half the dose but twice the frequency with the same intended overall dose intensity (DI). A total of 167 patients defined as having extensive SCLC with adverse prognostic features were randomised to receive either a 3 weekly regimen of cisplatin 60 mg m-2 i.v. on day 1 and etoposide 120 mg m-2 i.v. on day 1 and 100 mg b.d. orally on days 2 and 3 alternating with cyclophosphamide 600 mg m-2 i.v., doxorubicin 50 mg m-2 i.v. and vincristine 2 mg i.v. all on day 1 for a maximum of six courses (3 weekly); or treatment with the same drugs but with each course consisting of half the 3 weekly dose given every 10 or 11 days for a maximum of 12 courses. In the 10/11 day regimen overall response rate was 58.9% (95% CI, 47.9-69.2%) with 12.8% complete responses (CR). For the 3 weekly treatment the overall response rate was 44.9% (95% CI, 35.0-55.5%) with 10.1% CR. Median survival was similar in the two arms at 6.4 months (95% CI, 4.9-7.3 months) and 5.8 months (95% CI, 4.0-6.6 months) respectively. Survival at 1 year was 9.9% (95% CI, 5.0-18.5%) and 8.9% (95% CI, 4.6-16.6%). The 95% CI for the difference in survival at 1 year is -7.09% to +9.09%. Haematological toxicity and treatment delays owing to infection were more frequent with the 10/11 day regimen but other toxicities were equal in both arms. Other aspects of quality of life were measured in a small representative cohort of patients using a daily diary card (DDC). There was a trend of improved quality of life on the 10/11 day arm, but there was little difference between the two treatments. The trial shows that a low-dose/high-frequency regimen with the same DI as conventionally scheduled chemotherapy gives similar response rates and survival. This and other modifications of the schedule may offer new approaches to

  7. Report: Evaluation on diagnosis significance of single high frequency Ultrasonography and mammography and combination on Breast Cancer.

    PubMed

    Sun, Huifang; Wang, Bo; Ding, Changmao; Yu, Zhan; Gao, Jianbo

    2016-07-01

    To evaluate the diagnosis significance of single high-frequency ultrasonography and mammography and combination therapy of both on breast cancer. 352 cases of female breast cancer patients were selected from The First Affiliated Hospital of Zhengzhou University from January 2012 to December 2014. Among the 352 patients, 124 patients had only performed high-frequency ultrasonography detection, 102 cases of patients were only conducted mammography, and 126 patients had applied the combination detection of high-frequency ultrasonography and mammography. The coincidence rate of single mammography detection was 79.4%, the misdiagnosis rate was 10.8%, and the missed diagnosis rate was 9.8%; the coincidence rate of single high frequency ultrasonography detection was 83.9%, the misdiagnosis rate was 11.5%, the missed diagnosis rate was 4.6%; the coincidence rate of combination of high frequency ultrasonography detection was 89.7%, the misdiagnosis rate was 6.3%, the missed diagnosis rate was 4.0%. The detection rate and missed diagnosis rate of combination diagnosis had statistical difference with single high frequency ultrasonography and single mammography. There was no statistical difference on misdiagnosis rate. mammography and high frequency ultrasonography respectively had their own advantages. The combination application of both had better diagnosis complementary, and could significantly improved the detection rate and accuracy rate on breast cancer, and decreased the misdiagnosis rate and missed diagnosis rate. PMID:27592481

  8. Airway turbulence and changes in upper airway hydraulic diameter can be estimated from the intensity of high frequency inspiratory sounds in sleeping adults

    PubMed Central

    Rembold, Christopher M; Suratt, Paul M

    2014-01-01

    Obstructive sleep disordered breathing can cause death and significant morbidity in adults and children. We previously found that children with smaller upper airways (measured by magnetic resonance imaging while awake) generated loud high frequency inspiratory sounds (HFIS, defined as inspiratory sounds > 2 kHz) while they slept. The purpose of this study was (1) to determine what characteristics of airflow predicted HFIS intensity, and (b) to determine if we could calculate changes in hydraulic diameter (D) in both an in vitro model and in the upper airways of sleeping humans. In an in vitro model, high frequency sound intensity was an estimate of airflow turbulence as reflected by the Reynold's number (Re). D of the in vitro model was calculated using Re, the pressure gradient, Swamee–Jain formula and Darcy formula. D was proportional to but smaller than the actual diameters (r2 = 0.94). In humans, we measured HFIS intensity and the pressure gradient across the upper airway (estimated with oesophageal pressure, Pes) during polysomnography in four adult volunteers and applied the same formulae to calculate D. At apnoea termination when the airway opens, we observed (1) an increase in HFIS intensity suggesting an increase in turbulence (higher Re), and (2) a larger calculated D. This method allows dynamic estimation of changes in relative upper airway hydraulic diameter (D) in sleeping humans with narrowed upper airways. PMID:24973405

  9. High frequency and allele-specific differences of BRCA1 founder mutations in breast cancer and ovarian cancer patients from Belarus.

    PubMed

    Bogdanova, N V; Antonenkova, N N; Rogov, Y I; Karstens, J H; Hillemanns, P; Dörk, T

    2010-10-01

    Breast cancer and ovarian cancer are common malignancies in Belarus accounting for about 3500 and 800 new cases per year, respectively. For breast cancer, the rates and age of onset appear to vary significantly in regions differentially affected by the Chernobyl accident. We assessed the frequency and distribution of three BRCA1 founder mutations 5382insC, 4153delA and Cys61Gly in two hospital-based series of 1945 unselected breast cancer patients and of 201 unselected ovarian cancer patients from Belarus as well as in 1019 healthy control females from the same population. Any of these mutations were identified in 4.4% of the breast cancer patients, 26.4% of the ovarian cancer patients and 0.5% of the controls. In the breast cancer patients, BRCA1 mutations were strongly associated with earlier age at diagnosis, with oestrogen receptor (ER) negative tumours and with a first-degree family history of breast cancer, although only 35% of the identified BRCA1 mutation carriers had such a family history. There were no marked differences in the regional distribution of BRCA1 mutations, so that the significant differences in age at diagnosis and family history of breast cancer patients from areas afflicted by the Chernobyl accident could not be explained by BRCA1. We next observed a higher impact and a shifted mutational spectrum of BRCA1 in the series of Byelorussian ovarian cancer patients where the three founder mutations accounted for 26.4% (53/201). While the Cys61Gly mutation appeared underrepresented in ovarian cancer as compared with breast cancer cases from the same population (p = 0.01), the 4153delA mutation made a higher contribution to ovarian cancer than to breast cancer (p < 0.01). BRCA1 mutations were significantly enriched among ovarian cancer cases with a first-degree family history of breast or ovarian cancer, whereas the median age at ovarian cancer diagnosis was not different between mutation carriers and non-carriers. Taken together, these results

  10. Forward-planning intensity-modulated radiotherapy technique for prostate cancer.

    PubMed

    Metwaly, Mohamed; Awaad, Awaad Mousa; El-Sayed, El-Sayed Mahmoud; Sallam, Abdel Sattar Mohamed

    2007-11-05

    In this study, we present an intensity-modulated radiotherapy technique based on forward planning dose calculations to provide a concave dose distribution to the prostate and seminal vesicles by means of modified dynamic arc therapy (M-DAT). Dynamic arcs (350 degrees) conforming to the beam's eye view of the prostate and seminal vesicles while shielding the rectum, combined with two lateral oblique conformal fields (15 degrees with respect to laterals) fitting the prostate only,were applied to deliver doses of 78 Gy and 61.23 Gy in 39 fractions to the prostate and seminal vesicles respectively. Dynamic wedges (45 degrees of thick end, anteriorly oriented) were used with conformal beams to adjust the dose homogeneity to the prostate, although in some cases, hard wedges (30 degrees of thick part,inferiorly oriented) were used with arcs to adjust the dose coverage to the seminal vesicles. The M-DAT was applied to 10 patients in supine and 10 patients in prone positioning to determine the proper patient positioning for optimum protection of the rectum. The M-DAT was compared with the simplified intensity-modulated arc therapy (SIMAT) technique, composed of three phases of bilateral dynamic arcs. The mean rectal dose in M-DAT for prone patients was 22.5 +/- 5.1 Gy; in M-DAT and SIMAT for supine patients, it was 30.2 +/- 5.1 Gy and 39.4 +/- 6.0 Gy respectively. The doses to 15%, 25%, 35%, and 50% of the rectum volume in M-DAT for prone patients were 44.5 +/- 10.2 Gy, 33.0 +/- 8.2 Gy, 25.3 +/- 6.4 Gy, and 16.3 +/- 5.6 Gy respectively. These values were lower than those in M-DAT and in SIMAT for supine patients by 7.7%, 18.2%, 22.4%, and 28.5% and by 25.0%, 32.1%, 34.9%, and 41.9% of the prescribed dose (78 Gy) respectively. Ion chamber measurements showed good agreement of the calculated and measured isocentric dose (maximum deviation of 3.5%). Accuracy of the dose distribution calculation was evaluated by film dosimetry using a gamma index, allowing 3% dose variation and

  11. Impact of geometric uncertainties on dose calculations for intensity modulated radiation therapy of prostate cancer

    NASA Astrophysics Data System (ADS)

    Jiang, Runqing

    Intensity-modulated radiation therapy (IMRT) uses non-uniform beam intensities within a radiation field to provide patient-specific dose shaping, resulting in a dose distribution that conforms tightly to the planning target volume (PTV). Unavoidable geometric uncertainty arising from patient repositioning and internal organ motion can lead to lower conformality index (CI) during treatment delivery, a decrease in tumor control probability (TCP) and an increase in normal tissue complication probability (NTCP). The CI of the IMRT plan depends heavily on steep dose gradients between the PTV and organ at risk (OAR). Geometric uncertainties reduce the planned dose gradients and result in a less steep or "blurred" dose gradient. The blurred dose gradients can be maximized by constraining the dose objective function in the static IMRT plan or by reducing geometric uncertainty during treatment with corrective verification imaging. Internal organ motion and setup error were evaluated simultaneously for 118 individual patients with implanted fiducials and MV electronic portal imaging (EPI). A Gaussian probability density function (PDF) is reasonable for modeling geometric uncertainties as indicated by the 118 patients group. The Gaussian PDF is patient specific and group standard deviation (SD) should not be used for accurate treatment planning for individual patients. In addition, individual SD should not be determined or predicted from small imaging samples because of random nature of the fluctuations. Frequent verification imaging should be employed in situations where geometric uncertainties are expected. Cumulative PDF data can be used for re-planning to assess accuracy of delivered dose. Group data is useful for determining worst case discrepancy between planned and delivered dose. The margins for the PTV should ideally represent true geometric uncertainties. The measured geometric uncertainties were used in this thesis to assess PTV coverage, dose to OAR, equivalent

  12. Postoperative intensity modulated radiation therapy in high risk prostate cancer: a dosimetric comparison.

    PubMed

    Digesú, Cinzia; Cilla, Savino; De Gaetano, Andrea; Massaccesi, Mariangela; Macchia, Gabriella; Ippolito, Edy; Deodato, Francesco; Panunzi, Simona; Iapalucci, Chiara; Mattiucci, Gian Carlo; D'Angelo, Elisa; Padula, Gilbert D A; Valentini, Vincenzo; Cellini, Numa; Piermattei, Angelo; Morganti, Alessio G

    2011-01-01

    The aim of this study was to compare intensity-modulated radiation therapy (IMRT) with 3D conformal technique (3D-CRT), with respect to target coverage and irradiation of organs at risk for high dose postoperative radiotherapy (PORT) of the prostate fossa. 3D-CRT and IMRT treatment plans were compared with respect to dose to the rectum and bladder. The dosimetric comparison was carried out in 15 patients considering 2 different scenarios: (1) exclusive prostate fossa irradiation, and (2) pelvic node irradiation followed by a boost on the prostate fossa. In scenario (1), a 3D-CRT plan (box technique) and an IMRT plan were calculated and compared for each patient. In scenario (2), 3 treatment plans were calculated and compared for each patient: (a) 3D-CRT box technique for both pelvic (prophylactic nodal irradiation) and prostate fossa irradiation (3D-CRT only); (b) 3D-CRT box technique for pelvic irradiation followed by an IMRT boost to the prostatic fossa (hybrid 3D-CRT and IMRT); and (c) IMRT for both pelvic and prostate fossa irradiation (IMRT only). For exclusive prostate fossa irradiation, IMRT significantly reduced the dose to the rectum (lower Dmean, V50%, V75%, V90%, V100%, EUD, and NTCP) and the bladder (lower Dmean, V50%, V90%, EUD and NTCP). When prophylactic irradiation of the pelvis was also considered, plan C (IMRT only) performed better than plan B (hybrid 3D-CRT and IMRT) as respect to both rectum and bladder irradiation (reduction of Dmean, V50%, V75%, V90%, equivalent uniform dose [EUD], and normal tissue complication probability [NTCP]). Plan (b) (hybrid 3D-CRT and IMRT) performed better than plan (a) (3D-CRT only) with respect to dose to the rectum (lower Dmean, V75%, V90%, V100%, EUD, and NTCP) and the bladder (Dmean, EUD, and NTCP). Postoperative IMRT in prostate cancer significantly reduces rectum and bladder irradiation compared with 3D-CRT.

  13. Reference-tissue correction of T2-weighted signal intensity for prostate cancer detection

    NASA Astrophysics Data System (ADS)

    Peng, Yahui; Jiang, Yulei; Oto, Aytekin

    2014-03-01

    The purpose of this study was to investigate whether correction with respect to reference tissue of T2-weighted MRimage signal intensity (SI) improves its effectiveness for classification of regions of interest (ROIs) as prostate cancer (PCa) or normal prostatic tissue. Two image datasets collected retrospectively were used in this study: 71 cases acquired with GE scanners (dataset A), and 59 cases acquired with Philips scanners (dataset B). Through a consensus histology- MR correlation review, 175 PCa and 108 normal-tissue ROIs were identified and drawn manually. Reference-tissue ROIs were selected in each case from the levator ani muscle, urinary bladder, and pubic bone. T2-weighted image SI was corrected as the ratio of the average T2-weighted image SI within an ROI to that of a reference-tissue ROI. Area under the receiver operating characteristic curve (AUC) was used to evaluate the effectiveness of T2-weighted image SIs for differentiation of PCa from normal-tissue ROIs. AUC (+/- standard error) for uncorrected T2-weighted image SIs was 0.78+/-0.04 (datasets A) and 0.65+/-0.05 (datasets B). AUC for corrected T2-weighted image SIs with respect to muscle, bladder, and bone reference was 0.77+/-0.04 (p=1.0), 0.77+/-0.04 (p=1.0), and 0.75+/-0.04 (p=0.8), respectively, for dataset A; and 0.81+/-0.04 (p=0.002), 0.78+/-0.04 (p<0.001), and 0.79+/-0.04 (p<0.001), respectively, for dataset B. Correction in reference to the levator ani muscle yielded the most consistent results between GE and Phillips images. Correction of T2-weighted image SI in reference to three types of extra-prostatic tissue can improve its effectiveness for differentiation of PCa from normal-tissue ROIs, and correction in reference to the levator ani muscle produces consistent T2-weighted image SIs between GE and Phillips MR images.

  14. Postoperative Intensity-Modulated Arc Therapy for Cervical and Endometrial Cancer: A Prospective Report on Toxicity

    SciTech Connect

    Vandecasteele, Katrien; Tummers, Philippe; Makar, Amin; Eijkeren, Marc van; Delrue, Louke; Denys, Hannelore; Lambert, Bieke; Beerens, Anne-Sophie; Van den Broecke, Rudy; Lambein, Kathleen; Fonteyne, Valerie; De Meerleer, Gert

    2012-10-01

    Purpose: To report on toxicity after postoperative intensity-modulated arc therapy (IMAT) for cervical (CC) and endometrial cancer (EC). Methods and Materials: Twenty-four CC and 41 EC patients were treated with postoperative IMAT. If indicated, para-aortic lymph node irradiation (preventive or when affected, PALN) and/or concomitant cisplatin (40 mg/m Superscript-Two , weekly) was administered. The prescribed dose for IMAT was 45 Gy (CC, 25 fractions) and 46 Gy (EC, 23 fractions), followed by a brachytherapeutic boost if possible. Radiation-related toxicity was assessed prospectively. The effect of concomitant cisplatin and PALN irradiation was evaluated. Results: Regarding acute toxicity (n = 65), Grade 3 and 2 acute gastrointestinal toxicity was observed in zero and 63% of patients (79% CC, 54% EC), respectively. Grade 3 and 2 acute genitourinary toxicity was observed in 1% and 18% of patients, respectively. Grade 2 (21%) and 3 (12%) hematologic toxicity (n = 41) occurred only in CC patients. Seventeen percent of CC patients and 2% of EC patients experienced Grade 2 fatigue and skin toxicity, respectively. Adding cisplatin led to an increase in Grade >2 nausea (57% vs. 9%; p = 0.01), Grade 2 nocturia (24% vs. 4%; p = 0.03), Grade {>=}2 hematologic toxicity (38% vs. nil, p = 0.003), Grade {>=}2 leukopenia (33% vs. nil, p = 0.009), and a strong trend toward more fatigue (14% vs. 2%; p = 0.05). Para-aortic lymph node irradiation led to an increase of Grade 2 nocturia (31% vs. 4%, p = 0.008) and a strong trend toward more Grade >2 nausea (44% vs. 18%; p = 0.052). Regarding late toxicity (n = 45), no Grade 3 or 4 late toxicity occurred. Grade 2 gastrointestinal toxicity, genitourinary toxicity, and fatigue occurred in 4%, 9%, and 1% of patients. Neither concomitant cisplatin nor PALN irradiation increased late toxicity rates. Conclusions: Postoperative IMAT for EC or CC is associated with low acute and late toxicity. Concomitant chemotherapy and PALN irradiation

  15. Effectiveness of robust optimization in intensity-modulated proton therapy planning for head and neck cancers

    SciTech Connect

    Liu Wei; Li Xiaoqiang; Park, Peter C.; Ronald Zhu, X.; Mohan, Radhe; Frank, Steven J.; Li Yupeng; Dong Lei

    2013-05-15

    Purpose: Intensity-modulated proton therapy (IMPT) is highly sensitive to uncertainties in beam range and patient setup. Conventionally, these uncertainties are dealt using geometrically expanded planning target volume (PTV). In this paper, the authors evaluated a robust optimization method that deals with the uncertainties directly during the spot weight optimization to ensure clinical target volume (CTV) coverage without using PTV. The authors compared the two methods for a population of head and neck (H and N) cancer patients. Methods: Two sets of IMPT plans were generated for 14 H and N cases, one being PTV-based conventionally optimized and the other CTV-based robustly optimized. For the PTV-based conventionally optimized plans, the uncertainties are accounted for by expanding CTV to PTV via margins and delivering the prescribed dose to PTV. For the CTV-based robustly optimized plans, spot weight optimization was guided to reduce the discrepancy in doses under extreme setup and range uncertainties directly, while delivering the prescribed dose to CTV rather than PTV. For each of these plans, the authors calculated dose distributions under various uncertainty settings. The root-mean-square dose (RMSD) for each voxel was computed and the area under the RMSD-volume histogram curves (AUC) was used to relatively compare plan robustness. Data derived from the dose volume histogram in the worst-case and nominal doses were used to evaluate the plan optimality. Then the plan evaluation metrics were averaged over the 14 cases and were compared with two-sided paired t tests. Results: CTV-based robust optimization led to more robust (i.e., smaller AUCs) plans for both targets and organs. Under the worst-case scenario and the nominal scenario, CTV-based robustly optimized plans showed better target coverage (i.e., greater D{sub 95%}), improved dose homogeneity (i.e., smaller D{sub 5%}- D{sub 95%}), and lower or equivalent dose to organs at risk. Conclusions: CTV

  16. Whole pelvic radiotherapy for prostate cancer using 3D conformal and intensity-modulated radiotherapy

    SciTech Connect

    Ashman, Jonathan B.; Zelefsky, Michael J. . E-mail: zelefskm@mskcc.org; Hunt, Margie S.; Leibel, Steven A.; Fuks, Zvi

    2005-11-01

    Purpose: To investigate the correlations between observed clinical morbidity and dosimetric parameters for whole pelvic radiotherapy (WPRT) for prostate cancer using either three-dimensional conformal radiotherapy (3D-CRT) or intensity-modulated radiotherapy (IMRT). Methods and Materials: Between December 1996 and January 2002, 27 patients with prostate adenocarcinoma were treated with conformal WPRT as part of their definitive treatment. WPRT was delivered with 3D-CRT in 14 patients and with IMRT in 13 patients. For each of the patients treated with IMRT, optimized conventional two-dimensional (2D) and 3D-CRT plans were retrospectively generated for the whole pelvic phase of the treatment. Dose-volume histograms for the bowel, bladder, and rectum were compared for the three techniques. Acute toxicities were evaluated for all 27 patients, and late toxicities were evaluated for 25 patients with sufficient follow-up. Toxicities were scored according to the Radiation Therapy Oncology Group morbidity grading scales. Median follow-up was 30 months. Results: Three-dimensional-CRT resulted in a 40% relative reduction (p < 0.001) in the volume of bowel receiving 45 Gy compared with 2D, and IMRT provided a further 60% reduction relative to 3D-CRT (p < 0.001). Compared with either 2D or 3D-CRT, IMRT reduced the volume of rectum receiving 45 Gy by 90% (p < 0.001). Overall, 9 patients (33%) experienced acute Grade 2 gastrointestinal (GI) toxicity, and only 1 of these patients was treated with IMRT. Antidiarrhea medication was required for 6 patients (22%). However, 5 of these 6 patients also received chemotherapy, and none were treated with IMRT. No Grade 3 or higher acute or late GI toxicities were observed. No cases of late radiation enteritis were observed. Acute and late genitourinary toxicity did not appear significantly increased by the addition of conformal WPRT. Conclusions: Compared to conventional 2D planning, conformal planning for WPRT resulted in significant

  17. Larynx-sparing techniques using intensity-modulated radiation therapy for oropharyngeal cancer

    SciTech Connect

    Bar Ad, Voichita; Lin, Haibo; Hwang, Wei-Ting; Deville, Curtiland; Dutta, Pinaki R.; Tochner, Zelig; Both, Stefan

    2012-01-01

    The purpose of the current study was to explore whether the laryngeal dose can be reduced by using 2 intensity-modulated radiation therapy (IMRT) techniques: whole-neck field IMRT technique (WF-IMRT) vs. junctioned IMRT (J-IMRT). The effect on planning target volumes (PTVs) coverage and laryngeal sparing was evaluated. WF-IMRT technique consisted of a single IMRT plan, including the primary tumor and the superior and inferior neck to the level of the clavicular heads. The larynx was defined as an organ at risk extending superiorly to cover the arytenoid cartilages and inferiorly to include the cricoid cartilage. The J-IMRT technique consisted of an IMRT plan for the primary tumor and the superior neck, matched to conventional antero-posterior opposing lower neck fields at the level of the thyroid notch. A central block was used for the anterior lower neck field at the level of the larynx to restrict the dose to the larynx. Ten oropharyngeal cancer cases were analyzed. Both the primary site and bilateral regional lymphatics were included in the radiotherapy targets. The averaged V95 for the PTV57.6 was 99.2% for the WF-IMRT technique compared with 97.4% (p = 0.02) for J-IMRT. The averaged V95 for the PTV64 was 99.9% for the WF-IMRT technique compared with 98.9% (p = 0.02) for J-IMRT and the averaged V95 for the PT70 was 100.0% for WF-IMRT technique compared with 99.5% (p = 0.04) for J-IMRT. The averaged mean laryngeal dose was 18 Gy with both techniques. The averaged mean doses within the matchline volumes were 69.3 Gy for WF-MRT and 66.2 Gy for J-IMRT (p = 0.03). The WF-IMRT technique appears to offer an optimal coverage of the target volumes and a mean dose to the larynx similar with J-IMRT and should be further evaluated in clinical trials.

  18. Optimal beam design on intensity-modulated radiation therapy with simultaneous integrated boost in nasopharyngeal cancer

    SciTech Connect

    Cheng, Mei-Chun; Hu, Yu-Wen; Liu, Ching-Sheng; Lee, Jeun-Shenn; Huang, Pin-I; Yen, Sang-Hue; Lee, Yuh-Lin; Hsieh, Chun-Mei; Shiau, Cheng-Ying

    2014-10-01

    This study aims to determine the optimal beam design among various combinations of field numbers and beam trajectories for intensity-modulated radiation therapy (IMRT) with simultaneous integrated boost (SIB) technique for the treatment of nasopharyngeal cancer (NPC). We used 10 fields with gantry angles of 155°, 130°, 75°, 25°, 0° L, 0° R, 335°, 285°, 230°, and 205° denoted as F10. To decrease doses in the spinal cord, the F10 technique was designed by featuring 2 pairs of split-opposed beam fields at 155° to 335° and 205° to 25°, as well as one pair of manually split beam fields at 0°. The F10 technique was compared with 4 other common field arrangements: F7E, 7 fields with 50° equally spaced gantry angles; F7, the basis of F10 with 155°, 130°, 75°, 0°, 285°, 230°, and 205°; F9E, 9 fields with 40° equally spaced gantry angles; and FP, 7 posterior fields with 180°, 150°, 120°, 90°, 270°, 240°, and 210°. For each individual case of 10 patients, the customized constraints derived after optimization with the standard F10 technique were applied to 4 other field arrangements. The 4 new optimized plans of each individual case were normalized to achieve the same coverage of planning target volume (PTV){sub 63} {sub Gy} as that of the standard F10 technique. The F10 field arrangement exhibited the best coverage in PTV{sub 70} {sub Gy} and the least mean dose in the trachea-esophagus region. Furthermore, the F10 field arrangement demonstrated the highest level of conformity in the low-dose region and the least monitor unit. The F10 field arrangement performed more outstandingly than the other field arrangements in PTV{sub 70} {sub Gy} coverage and spared the central organ. This arrangement also exhibited the highest conformity and delivery efficiency. The F10 technique is recommended as the standard beam geometry for the SIB-IMRT of NPC.

  19. Homogeneous and inhomogeneous broadenings and the Voigt line shapes in the phase-resolved and intensity sum-frequency generation vibrational spectroscopy.

    PubMed

    Chen, Shun-Li; Fu, Li; Gan, Wei; Wang, Hong-Fei

    2016-01-21

    In this report, we show that the ability to measure the sub-1 cm(-1) resolution phase-resolved and intensity high-resolution broadband sum frequency generation vibrational spectra of the -CN stretch vibration of the Langmuir-Blodgett (LB) monolayer of the 4-n-octyl-4'-cyanobiphenyl (8CB) on the z-cut α-quartz surface allows the direct comparison and understanding of the homogeneous and inhomogeneous broadenings in the imaginary and intensity SFG vibrational spectral line shapes in detail. The difference of the full width at half maximum (FWHM) of the imaginary and intensity sum-frequency generation vibrational spectroscopy spectra of the same vibrational mode is the signature of the Voigt line shape and it measures the relative contribution to the overall line shape from the homogeneous and inhomogeneous broadenings in SFG vibrational spectra. From the phase-resolved and intensity spectra, we found that the FWHM of the 2238.00 ± 0.02 cm(-1) peak in the phase-resolved imaginary and intensity spectra is 19.2 ± 0.2 cm(-1) and 21.6 ± 0.4 cm(-1), respectively, for the -CN group of the 8CB LB monolayer on the z-cut α-quartz crystal surface. The FWHM width difference of 2.4 cm(-1) agrees quantitatively with a Voigt line shape with a homogeneous broadening half width of Γ = 5.29 ± 0.08 cm(-1) and an inhomogeneous standard derivation width Δω = 5.42 ± 0.07 cm(-1). These results shed new lights on the understanding and interpretation of the line shapes of both the phase-resolved and the intensity SFG vibrational spectra, as well as other incoherent and coherent spectroscopic techniques in general. PMID:26801040

  20. Homogeneous and inhomogeneous broadenings and the Voigt line shapes in the phase-resolved and intensity sum-frequency generation vibrational spectroscopy

    NASA Astrophysics Data System (ADS)

    Chen, Shun-Li; Fu, Li; Gan, Wei; Wang, Hong-Fei

    2016-01-01

    In this report, we show that the ability to measure the sub-1 cm-1 resolution phase-resolved and intensity high-resolution broadband sum frequency generation vibrational spectra of the -CN stretch vibration of the Langmuir-Blodgett (LB) monolayer of the 4-n-octyl-4'-cyanobiphenyl (8CB) on the z-cut α-quartz surface allows the direct comparison and understanding of the homogeneous and inhomogeneous broadenings in the imaginary and intensity SFG vibrational spectral line shapes in detail. The difference of the full width at half maximum (FWHM) of the imaginary and intensity sum-frequency generation vibrational spectroscopy spectra of the same vibrational mode is the signature of the Voigt line shape and it measures the relative contribution to the overall line shape from the homogeneous and inhomogeneous broadenings in SFG vibrational spectra. From the phase-resolved and intensity spectra, we found that the FWHM of the 2238.00 ± 0.02 cm-1 peak in the phase-resolved imaginary and intensity spectra is 19.2 ± 0.2 cm-1 and 21.6 ± 0.4 cm-1, respectively, for the -CN group of the 8CB LB monolayer on the z-cut α-quartz crystal surface. The FWHM width difference of 2.4 cm-1 agrees quantitatively with a Voigt line shape with a homogeneous broadening half width of Γ = 5.29 ± 0.08 cm-1 and an inhomogeneous standard derivation width Δω = 5.42 ± 0.07 cm-1. These results shed new lights on the understanding and interpretation of the line shapes of both the phase-resolved and the intensity SFG vibrational spectra, as well as other incoherent and coherent spectroscopic techniques in general.

  1. Long-term cancer-related fatigue outcomes in patients with locally advanced prostate cancer after intensity-modulated radiotherapy combined with hormonal therapy

    PubMed Central

    Luo, Hua-Chun; Lei, Yong; Cheng, Hui-Hua; Fu, Zhi-Chao; Liao, Shao-Guang; Feng, Jing; Yin, Qin; Chen, Qun-Hua; Lin, Gui-Shan; Zhu, Jin-Feng; Xu, Jian-Feng; Wang, Dian

    2016-01-01

    Abstract The aim of our study was to investigate the relationship between cancer-related fatigue and clinical parameters, and the effect factors of fatigue for the prostate cancer patients. Long-term follow-up is performed using the Fatigue Symptom Inventory before treatment (A), at the end of intensity-modulated radiotherapy (B), and 3 months (C), 12 months (D), 24 months (E), 36 months (F), and 48 months (G) after the end of intensity-modulated radiotherapy. Three dimensions of fatigue are assessed during follow-up: severity, perceived interference with quality of life, and duration in the past week. In all, 97 patients with locally advanced prostate cancer were enrolled in the study. Median follow-up time was 43.9 months. The fatigue index was significantly higher in the prostate-specific antigen >20 ng/mL, Gleason score >8, the Eastern Cooperative Oncology Group scores, and the higher education. The most severe fatigue occurred at time points B and C. The score for duration of fatigue fluctuated across the time points, with significantly increased scores at time points D, E, and F. In conclusion, we show that cancer-related fatigue is the important symptom which affects the quality of life for the prostate cancer patients. For patients with locally advanced prostate cancer with a high Eastern Cooperative Oncology Group score, a Gleason score of >8 points, prostate-specific antigen levels of >20 ng/mL, and high education, attention should be paid to the interference of fatigue with quality of life, especially general level of activity, ability to concentrate, and mood, after radiotherapy combined with hormonal therapy. PMID:27336890

  2. Si nanoparticles as sensitizers for radio frequency-induced cancer hyperthermia

    NASA Astrophysics Data System (ADS)

    Kabashin, A. V.; Tamarov, K. P.; Ryabchikov, Yu. V.; Osminkina, L. A.; Zinovyev, S. V.; Kargina, J. V.; Gongalsky, M. B.; Al-Kattan, A.; Yakunin, V. G.; Sentis, M. L.; Ivanov, A. V.; Nikiforov, V. N.; Kanavin, A. P.; Zavestovskaya, I. N.; Timoshenko, V. Y.

    2016-03-01

    We review our recently obtained data on the employment of Si nanoparticles as sensitizers of radiofrequency (RF) - induced hyperthermia for mild cancer therapy tasks. Such an approach makes possible the heating of aqueous suspensions of Si nanoparticles by tens of degrees Celsius under relatively low intensities (1-5 W/cm2) of 27 MHz RF radiation. The heating effect is demonstrated for nanoparticles synthesized by laser ablation in water and mechanical grinding of porous silicon, while laser-ablated nanoparticles demonstrate a remarkably higher heating rate than porous silicon-based ones for the whole range of the used concentrations. The observed RF heating effect can be explained in the frame of a model considering the polarization of Si NPs and electrolyte in the external oscillating electromagnetic field and the corresponding release of heat by electric currents around the nanoparticles. Our tests evidence relative safety of Si nanostructures and their efficient dissolution in physiological solutions, suggesting potential clearance of nanoparticles from a living organism without any side effects. Profiting from Si nanoparticle-based heating, we finally demonstrate an efficient treatment of Lewis Lung carcinoma in vivo. The obtained data promise a breakthrough in the development of mild, non-invasive methods for cancer therapy.

  3. The Dosimetric Consequences of Intensity Modulated Radiotherapy for Cervix Cancer: The Impact of Organ Motion, Deformation and Tumour Regression

    NASA Astrophysics Data System (ADS)

    Lim, Karen Siah Huey

    Hypothesis: In intensity modulated radiotherapy (IMRT) for cervix cancer, the dose received by the tumour target and surrounding normal tissues is significantly different to that indicated by a single static plan. Rationale: The optimal use of IMRT in cervix cancer requires a greater attention to clinical target volume (CTV) definition and tumour & normal organ motion to assure maximum tumour control with the fewest side effects. Research Aims: 1) Generate consensus CTV contouring guidelines for cervix cancer; 2) Evaluate intra-pelvic tumour and organ dynamics during radiotherapy; 3) Analyze the dose consequences of intra-pelvic organ dynamics on different radiotherapy strategies. Results: Consensus CTV definitions were generated using experts-in-the-field. Substantial changes in tumour volume and organ motion, resulted in significant reductions in accumulated dose to tumour targets and variability in accumulated dose to surrounding normal tissues. Significance: Formalized CTV definitions for cervix cancer is important in ensuring consistent standards of practice. Complex and unpredictable tumour and organ dynamics mandates daily soft-tissue image guidance if IMRT is used. To maximize the benefits of IMRT for cervix cancer, a strategy of adaptation is necessary.

  4. Physical activity type and intensity among rural breast cancer survivors: patterns and associations with fatigue and depressive symptoms

    PubMed Central

    Markwell, Stephen J.; Courneya, Kerry S.; McAuley, Edward; Verhulst, Steven

    2011-01-01

    Introduction Our study aims were to describe physical activity patterns and associations with fatigue and depressive symptoms among rural breast cancer survivors. Methods Population-based, mailed survey of 483 rural breast cancer survivors including the International Physical Activity Questionnaire (IPAQ). Results With regard to type and intensity, domestic/gardening and moderate intensity accounted for the largest percentage of total energy expenditure (i.e., 60% and 69%, respectively). MET-mins/week variables were categorized as 0, > 0 to < 500, and ≥ 500 to reflect sedentary, insufficient, and meets current public health recommendations. After adjustment, fatigue was significantly associated with domestic/gardening (mean fatigue for sedentary, insufficient, and meets recommendations were 18.9, 16.4, and 13.4, respectively; p=.0019), leisure activity (means were 16.0, 14.5, and 11.8, respectively; p=.047), moderate intensity (means were 18.4, 16.7, and 13.7, respectively; p=.011), and daily minutes sitting (means for ≤ 120 min, > 120 to ≤ 360 min, and > 360 min of sitting were 12.5, 14.2, and 17.2, respectively; p=.0029). Fatigue was not associated with occupational, transportation, walking, or vigorous activity. After adjustment, only leisure activity was associated with depressive symptoms (means for sedentary, insufficient, and meets recommendations were 7.8, 7.7, and 6.2, respectively; p=.039). Conclusions Physical activity measurement tools that do not include domestic/gardening activities may underestimate physical activity in rural breast cancer populations. Physical activity associations with fatigue and depressive symptoms differed based on physical activity type and intensity suggesting hypotheses related to exercise effects on fatigue and depressive symptoms. PMID:21110134

  5. Thermoacoustic contrast of prostate cancer due to heating by very high frequency irradiation

    NASA Astrophysics Data System (ADS)

    Patch, S. K.; Hull, D.; Thomas, M.; Griep, SK; Jacobsohn, K.; See, WA

    2015-01-01

    Applying the thermoacoustic (TA) effect to diagnostic imaging was first proposed in the 1980s. The object under test is irradiated by high-power pulses of electromagnetic energy, which heat tissue and cause thermal expansion. Outgoing TA pressure pulses are detected by ultrasound transducers and reconstructed to provide images of the object. The TA contrast mechanism is strongly dependent upon the frequency of the irradiating electromagnetic pulse. When very high frequency (VHF) electromagnetic irradiation is utilized, TA signal production is driven by ionic content. Prostatic fluids contain high levels of ionic metabolites, including citrate, zinc, calcium, and magnesium. Healthy prostate glands produce more ionic metabolites than diseased glands. VHF pulses are therefore expected to generate stronger TA signal in healthy prostate glands than in diseased glands. A benchtop system for performing ex vivo TA computed tomography with VHF energy is described and images are presented. The system utilizes irradiation pulses of 700 ns duration exceeding 20 kW power. Reconstructions frequently visualize anatomic landmarks such as the urethra and verumontanum. TA reconstructions from three freshly excised human prostate glands with little, moderate, and severe cancerous involvement are compared with histology. TA signal strength is negatively correlated with percent cancerous involvement in this small sample size. For the 45 regions of interest analyzed, a reconstruction value of 0.4 mV provides 100% sensitivity but only 29% specificity. This sample size is far too small to draw sweeping conclusions, but the results warrant a larger volume study including comparison of TA images to the gold standard, histology.

  6. Thermoacoustic contrast of prostate cancer due to heating by very high frequency irradiation.

    PubMed

    Patch, S K; Hull, D; Thomas, M; Griep, S K; Jacobsohn, K; See, W A

    2015-01-21

    Applying the thermoacoustic (TA) effect to diagnostic imaging was first proposed in the 1980s. The object under test is irradiated by high-power pulses of electromagnetic energy, which heat tissue and cause thermal expansion. Outgoing TA pressure pulses are detected by ultrasound transducers and reconstructed to provide images of the object. The TA contrast mechanism is strongly dependent upon the frequency of the irradiating electromagnetic pulse. When very high frequency (VHF) electromagnetic irradiation is utilized, TA signal production is driven by ionic content. Prostatic fluids contain high levels of ionic metabolites, including citrate, zinc, calcium, and magnesium. Healthy prostate glands produce more ionic metabolites than diseased glands. VHF pulses are therefore expected to generate stronger TA signal in healthy prostate glands than in diseased glands. A benchtop system for performing ex vivo TA computed tomography with VHF energy is described and images are presented. The system utilizes irradiation pulses of 700 ns duration exceeding 20 kW power. Reconstructions frequently visualize anatomic landmarks such as the urethra and verumontanum. TA reconstructions from three freshly excised human prostate glands with little, moderate, and severe cancerous involvement are compared with histology. TA signal strength is negatively correlated with percent cancerous involvement in this small sample size. For the 45 regions of interest analyzed, a reconstruction value of 0.4 mV provides 100% sensitivity but only 29% specificity. This sample size is far too small to draw sweeping conclusions, but the results warrant a larger volume study including comparison of TA images to the gold standard, histology.

  7. Detection and attribution of non-stationarity in intensity and frequency of daily and 4-h extreme rainfall of Hyderabad, India

    NASA Astrophysics Data System (ADS)

    Agilan, V.; Umamahesh, N. V.

    2015-11-01

    The high intensity rainfall has a significant contribution in urban area flooding and understanding this high intensity rainfall over urban areas may help us to reduce the damage caused by urban floods. In this study, the changes in Hyderabad city daily and sub-daily (4-h) extreme rainfall are analyzed using various climate change detection indices. Our analysis indicates that there is increasing trend in intensity and frequency of Hyderabad city daily extreme rainfall. In addition, increasing trend in intensity and frequency of monsoon months' (June-August) 1 a.m. to 4 a.m., 5 p.m. to 8 p.m. and 9 p.m. to 12 a.m. and non-monsoon months' 5 p.m. to 8 p.m. extreme rainfall is also observed. Based on recent theoretical development in the Extreme Value Theory (EVT), the changes in extreme rainfall of Hyderabad city are further attributed through modelling the non-stationarity (trend) present in the extreme rainfall intensity and frequency. The extreme rainfall intensity is modelled with peaks-over-threshold (POT) based Generalized Pareto Distribution (GPD) and frequency is modelled using inhomogeneous Poisson distribution. The trend is incorporated as covariate in the scale parameter (σ) of the GPD and the rate parameter (λ) of the Poisson distribution. In this study, four physical processes, i.e. Urbanization, El Niño-Southern Oscillation (ENSO) cycle, local temperature changes, and global warming are used as covariates. Further, the combinations of these covariates are also considered for modelling the non-stationarity. Based on covariates and their combinations, fifteen non-stationary models and one stationary model are constructed and the best model is chosen based on the corrected Akaike Information Criterion (AICc) value. The covariate(s) in the best chosen non-stationary statistical model is/are attributed as the most significant physical process/processes which causes non-stationarity in the series. The study results indicate that the non-stationarity in

  8. Increased chromosome-type chromosome aberration frequencies as biomarkers of cancer risk in a blackfoot endemic area.

    PubMed

    Liou, S H; Lung, J C; Chen, Y H; Yang, T; Hsieh, L L; Chen, C J; Wu, T N

    1999-04-01

    To examine whether biomarkers such as sister chromatid exchanges (SCEs) and chromosome aberrations (CAs) can predict cancer development, a nested case-control study was performed in a blackfoot endemic area with a known high cancer risk. A cohort of 686 residents was recruited from three villages in the blackfoot endemic area. Personal characteristics were collected, and venous blood was drawn for lymphocyte culture and stored in a refrigerator. The vital status and cancer development were followed using the National Death Registry, Cancer Registry, and Blackfoot Disease Registry. The follow-up period was from August 1991 to July 1995. During this 4-year period, 31 residents developed various types of cancer. Blood culture samples from nine of these subjects were unsuitable for experiments due to improper storage. Finally, a total of 22 cancer cases had cytogenetic samples that could be analyzed. Twenty-two control subjects were selected from those who did not develop cancer in the study period, and these subjects were matched to cases by sex, age, smoking habits, and residential area. The results showed that there was no significant difference in the frequencies of SCE and chromatid-type CAs between the case and control groups. However, the frequencies of chromosome-type CAs, e.g., chromosome-type gaps, chromosome-type breaks, chromosome-type breaks plus exchanges, total chromosome-type aberrations, and total frequencies of CAs in the case group, were significantly higher than those in the control group (P < 0.05). The odds ratio of cancer risk in subjects with more than zero chromosome-type breaks was 5.0 (95% confidence interval = 1.09-22.82) compared to those with zero chromosomal breaks. The odds ratios for more than zero chromosome-type breaks plus exchanges and a frequency of total chromosome-type aberrations of >1.007% were 11.0 and 12.0, respectively (P < 0.05). Subjects with a total CA frequency of >4.023% had a 9-fold increase for cancer risk. These

  9. Frequency of Precancerous Changes and Cervical Cancer Recorded in Three Health Centres in Tuzla Canton in Period 2010-2011

    PubMed Central

    Jahic, Mahira; Mulavdic, Mirsada; Dautbasic, Fatima; Fejzic, Mara; Jahic, Elmir

    2013-01-01

    Cervical cancer is the second most common cancer in the world and the leading cause of death. Frequency and mortality are significantly reduced thanks to cytological Papanicolau test (PAP). Regular PAP test can reduce approximately 80% of cases of this cancer Aim of the study: To examine frequency of cervical cancer and changes of cervix, the age of risk for the changes and effect of frequency of PAP test. Materials and methods: 3383 PAP (cytological) findings have been retrospectively ana lysed in three Health Centres of Tuzla Canton: Tuzla, Srebrenik and Sapna. During 2010 and 2011 protocols of Health Centers have been analyzed. Results: Analysis of 3383 smears detected the following: abnormal PAP tests in 20.8% (705) and without abnormalities in 79.1% (2678). Normal findings in 9.1% (311), inflammatory changes in 69.6% (2357), ASCUS in 12.9% (438), ASC-H in 0.3% (11), LSIL in 5.4% (183), HSIL in 1.4% (49) and Squamous cell carcinoma in 0.7% (24). Cervical cancer has mostly been found in women from Srebrenik 1.1% (15) and least in women from Tuzla 0.3%(4).The highest number of abnormal findings (ASCUS, ASC-H , LSIL, H SIL and Cc) was also found in women from Srebrenik 39.5% (279). The average age of the examinees with the cancer was 41.7. In 62.5% (15) of women PAP test was performed for the first time and they were diagnosed with cervical cancer. Cervical cancer hasn’t been found in women who had PAP test once a year or more. Conclusion: Women with the abnormal findings in their first PAP test and should be persuaded to accept the treatment in order to prevent development of cervical cancer. PMID:24511270

  10. Feasibility demonstration of frequency domain terahertz imaging in breast cancer margin determination

    PubMed Central

    Yngvesson, Sigfrid K.; St. Peter, Benjamin; Siqueira, Paul; Kelly, Patrick; Glick, Stephen; Karellas, Andrew; Khan, Ashraf

    2013-01-01

    In breast conservation surgery, surgeons attempt to remove malignant tissue along with a surrounding margin of healthy tissue. Subsequent pathological analysis determines if those margins are clear of malignant tissue, a process that typically requires at least one day. Only then can it be determined whether a follow-up surgery is necessary. This possibility of re-excision is undesirable in terms of reducing patient morbidity, emotional stress and healthcare. It has been shown that terahertz (THz) images of breast specimens can accurately differentiate between breast carcinoma, normal fibroglandular tissue, and adipose tissue. That study employed the Time-Domain Spectroscopy (TDS) technique. We are instead developing a new technique, Frequency-Domain Terahertz Imaging (FDTI). In this joint project between UMass/Amherst and UMass Medical School/Worcester (UMMS), we are investigating the feasibility of the FDTI technique for THz reflection imaging of breast cancer margins. Our system, which produces mechanically scanned images of size 2cm × 2cm, uses a THz gas laser. The system is calibrated with mixtures of water and ethanol and reflection coefficients as low as 1% have been measured. Images from phantoms and specimens cut from breast cancer lumpectomies at UMMS will be presented. Finally, there will be a discussion of a possible transition of this FDTI setup to a compact and inexpensive CMOS THz camera for use in the operating room. PMID:24353380

  11. Feasibility demonstration of frequency domain terahertz imaging in breast cancer margin determination

    NASA Astrophysics Data System (ADS)

    Yngvesson, Sigfrid K.; St. Peter, Benjamin; Siqueira, Paul; Kelly, Patrick; Glick, Stephen; Karellas, Andrew; Khan, Ashraf

    2012-03-01

    In breast conservation surgery, surgeons attempt to remove malignant tissue along with a surrounding margin of healthy tissue. Subsequent pathological analysis determines if those margins are clear of malignant tissue, a process that typically requires at least one day. Only then can it be determined whether a follow-up surgery is necessary. This possibility of re-excision is undesirable in terms of reducing patient morbidity, emotional stress and healthcare. It has been shown that terahertz (THz) images of breast specimens can accurately differentiate between breast carcinoma, normal fibroglandular tissue, and adipose tissue. That study employed the Time-Domain Spectroscopy (TDS) technique. We are instead developing a new technique, Frequency-Domain Terahertz Imaging (FDTI). In this joint project between UMass/Amherst and UMass Medical School/Worcester (UMMS), we are investigating the feasibility of the FDTI technique for THz reflection imaging of breast cancer margins. Our system, which produces mechanically scanned images of size 2cm x 2cm, uses a THz gas laser. The system is calibrated with mixtures of water and ethanol and reflection coefficients as low as 1% have been measured. Images from phantoms and specimens cut from breast cancer lumpectomies at UMMS will be presented. Finally, there will be a discussion of a possible transition of this FDTI setup to a compact and inexpensive CMOS THz camera for use in the operating room.

  12. A Phase 1 Study of Everolimus + Weekly Cisplatin + Intensity Modulated Radiation Therapy in Head-and-Neck Cancer

    SciTech Connect

    Fury, Matthew G.; Lee, Nancy Y.; Sherman, Eric; Ho, Alan L.; Rao, Shyam; Heguy, Adriana; Shen, Ronglai; Korte, Susan; Lisa, Donna; Ganly, Ian; Patel, Snehal; Wong, Richard J.; Shaha, Ashok; Shah, Jatin; Haque, Sofia; Katabi, Nora; Pfister, David G.

    2013-11-01

    Purpose: Elevated expression of eukaryotic protein synthesis initiation factor 4E (eIF4E) in histologically cancer-free margins of resected head and neck squamous cell carcinomas (HNSCCs) is mediated by mammalian target of rapamycin complex 1 (mTORC1) and has been associated with increased risk of disease recurrence. Preclinically, inhibition of mTORC1 with everolimus sensitizes cancer cells to cisplatin and radiation. Methods and Materials: This was single-institution phase 1 study to establish the maximum tolerated dose of daily everolimus given with fixed dose cisplatin (30 mg/m{sup 2} weekly × 6) and concurrent intensity modulated radiation therapy for patients with locally and/or regionally advanced head-and-neck cancer. The study had a standard 3 + 3 dose-escalation design. Results: Tumor primary sites were oral cavity (4), salivary gland (4), oropharynx (2), nasopharynx (1), scalp (1), and neck node with occult primary (1). In 4 of 4 cases in which resected HNSCC surgical pathology specimens were available for immunohistochemistry, elevated expression of eIF4E was observed in the cancer-free margins. The most common grade ≥3 treatment-related adverse event was lymphopenia (92%), and dose-limiting toxicities (DLTs) were mucositis (n=2) and failure to thrive (n=1). With a median follow up of 19.4 months, 2 patients have experienced recurrent disease. The maximum tolerated dose was everolimus 5 mg/day. Conclusions: Head-and-neck cancer patients tolerated everolimus at therapeutic doses (5 mg/day) given with weekly cisplatin and intensity modulated radiation therapy. The regimen merits further evaluation, especially among patients who are status post resection of HNSCCs that harbor mTORC1-mediated activation of eIF4E in histologically negative surgical margins.

  13. The doppler frequency shift caused by the inhomogeneities of a medium induced by pulses of intense laser radiation

    NASA Astrophysics Data System (ADS)

    Rozanov, N. N.; Kiselev, Al. S.; Kiselev, An. S.

    2008-08-01

    Self-reflection of pulses of intense laser radiation from an inhomogeneity induced by them in a medium with fast optical nonlinearity is analyzed. The reflected radiation is characterized by a considerable Doppler shift and by a signal magnitude that is sufficient for experimental detection.

  14. A new time-frequency method to reveal quantum dynamics of atomic hydrogen in intense laser pulses: Synchrosqueezing transform

    SciTech Connect

    Sheu, Yae-lin; Hsu, Liang-Yan; Wu, Hau-tieng; Li, Peng-Cheng; Chu, Shih-I

    2014-11-15

    This study introduces a new adaptive time-frequency (TF) analysis technique, the synchrosqueezing transform (SST), to explore the dynamics of a laser-driven hydrogen atom at an ab initio level, upon which we have demonstrated its versatility as a new viable venue for further exploring quantum dynamics. For a signal composed of oscillatory components which can be characterized by instantaneous frequency, the SST enables rendering the decomposed signal based on the phase information inherited in the linear TF representation with mathematical support. Compared with the classical type of TF methods, the SST clearly depicts several intrinsic quantum dynamical processes such as selection rules, AC Stark effects, and high harmonic generation.

  15. [Effects of low-intensity extremely high frequency electromagnetic radiation on chromatin structure of lymphoid cells in vivo and in vitro].

    PubMed

    Gapeev, A B; Lushnikov, K V; Shumilina, Iu V; Sirota, N P; Sadovnikov, V B; Chemeris, N K

    2003-01-01

    Using a comet assay technique, it was shown for the first time that low-intensity extremely high-frequency electromagnetic radiation (EHF EMR) in vivo causes oppositely directed effects on spatial organization of chromatin in cells of lymphoid organs. In 3 hrs after single whole-body exposure of NMRI mice for 20 min at 42.0 GHz and 0.15 mW/cm2, an increase by 16% (p < 0.03 as compared with control) and a decrease by 16% (p < 0.001) in fluorescence intensity of nucleoids stained with ethidium bromide were found in thymocytes and splenocytes, respectively. The fluorescence intensity of stained nucleoids in peripheral blood leukocytes was not changed after the exposure. The exposure of cells of Raji hunan lymphoid line and peripheral blood leukocytes to the EHF EMR in vitro induced a decrease in fluorescence intensity by 23% (p < 0.001) and 18% (p < 0.05), respectively. These effects can be determined by changes in a number of physiological alkali-labile sites in DNA of exposed cells. We suggested that the effects of low-intensity EHF EMR on the immune system cells are realized with the participation of neuroendocrine and central nervous systems.

  16. Breast cancer margin detection with a single frequency terahertz imaging system

    NASA Astrophysics Data System (ADS)

    Yngvesson, Sigfrid K.; Karellas, Andrew; Glick, Stephen; Khan, Ashraf; Siqueira, Paul R.; Kelly, Patrick A.; St. Peter, Benjamin

    2016-03-01

    The ability to discern malignant from benign tissue in excised human breast specimens in Breast Conservation Surgery (BCS) was evaluated using a prototype single frequency terahertz radiation. Terahertz (THz) images of the specimens in reflection mode were obtained by employing a gas laser source and mechanical scanning. The images were correlated with optical histological micrographs of the same specimens, and a mean discrimination of 73% was found for five out of six samples using Receiver Operating Characteristic (ROC) analysis. This result is similar to what has previously been obtained using Terahertz pulsed imaging (TPI) techniques. We will discuss the specific advantages of Single frequency THz imaging (SFTI) compared with TPI for potentially allowing the development of much faster, more compact and less expensive cancer imaging systems that could be adapted for employment in the operating room. The system design and characterization of the prototype SFTI system are discussed in detail. The initial results are encouraging but further development of the technology and clinical evaluation is needed to evaluate its feasibility in the clinical environment.

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

    PubMed Central

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

    2016-01-01

    Objective To investigate whether high-intensity focused ultrasound (HIFU) combined with microbubbles enhances the therapeutic effects of chemotherapy. Materials and Methods 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. Results 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. Conclusion High-intensity focused ultrasound combined with microbubbles enhances the therapeutic effects of gemcitabine chemotherapy in a pancreatic cancer xenograft model. PMID:27587968

  18. Spatially-dense, multi-spectral, frequency-domain diffuse optical tomography of breast cancer

    NASA Astrophysics Data System (ADS)

    Ban, Han Yong

    Diffuse optical tomography (DOT) employs near-infrared light to image the concentration of chromophores and cell organelles in tissue and thereby providing access to functional parameters that can differentiate cancerous from normal tissues. This thesis describes research at the bench and in the clinic that explores and identifies the potential of DOT breast cancer imaging. The bench and clinic instrumentation differ but share important features: they utilize a very large, spatially dense, set of source-detector pairs (10 7) for imaging in the parallel-plate geometry. The bench experiments explored three-dimensional (3D) image resolution and fidelity as a function of numerous parameters and also ascertained the effects of a chest wall phantom. The chest wall is always present but is typically ignored in breast DOT. My experiments clarified chest wall influences and developed schemes to mitigate these effects. Mostly, these schemes involved selective data exclusion, but their efficacy also depended on reconstruction approach. Reconstruction algorithms based on analytic (fast) Fourier inversion and linear algebraic techniques were explored. The clinical experiments centered around a DOT instrument that I designed, constructed, and have begun to test (in-vitro and in-vivo). This instrumentation offers many features new to the field. Specifically, the imager employs spatially-dense, multi-spectral, frequency-domain data; it possesses the world's largest optical source-detector density yet reported, facilitated by highly-parallel CCD-based frequency-domain imaging based on gain-modulation heterodyne detection. The instrument thus measures both phase and amplitude of the diffusive light waves. Other features include both frontal and sagittal breast imaging capabilities, ancillary cameras for measurement of breast boundary profiles, real-time data normalization, and mechanical improvements for patient comfort. The instrument design and construction is my most significant

  19. Intensive vs. Standard Post-Operative Surveillance in High-Risk Breast Cancer Patients (INSPIRE): Japan Clinical Oncology Group Study JCOG1204.

    PubMed

    Hojo, Takashi; Masuda, Norikazu; Mizutani, Tomonori; Shibata, Taro; Kinoshita, Takayuki; Tamura, Kenji; Hara, Fumikata; Fujisawa, Tomomi; Inoue, Kenichi; Saji, Shigehira; Nakamura, Kenichi; Fukuda, Haruhiko; Iwata, Hiroji

    2015-10-01

    This Phase III trial aims to determine the superiority of intensive follow-up to standard follow-up in terms of overall survival in high-risk breast cancer patients, who are expected to have recurrence rates of over 30% within 5 years after surgery. Eligible patients are randomized either to the intensive follow-up group or to the standard follow-up group; the former will undergo physical examination, bone scintigraphy, chest computed tomography, abdominal computed tomography, brain magnetic resonance imaging/computed tomography and frequent tumor marker evaluations, whereas the latter will undergo physical examination at the same frequency and tumor markers will be evaluated once a year. Mammography once a year is planned for both groups. The primary endpoint is overall survival. Patient accrual was started in November 2013. A total of 1700 patients will be enrolled for 3 years and followed up for 7 years after closure of accrual. This trial has been registered at the UMIN Clinical Trials Registry as UMIN000012429.

  20. Effect of 24 Sessions of High-Intensity Aerobic Interval Training Carried out at Either High or Moderate Frequency, a Randomized Trial

    PubMed Central

    Hatle, Håvard; Støbakk, Per Kristian; Mølmen, Harald Edvard; Brønstad, Eivind; Tjønna, Arnt Erik; Steinshamn, Sigurd; Skogvoll, Eirik; Wisløff, Ulrik; Ingul, Charlotte Björk; Rognmo, Øivind

    2014-01-01

    Purpose The training response of an intensified period of high-intensity exercise is not clear. Therefore, we compared the cardiovascular adaptations of completing 24 high-intensity aerobic interval training sessions carried out for either three or eight weeks, respectively. Methods Twenty-one healthy subjects (23.0±2.1 years, 10 females) completed 24 high-intensity training sessions throughout a time-period of either eight weeks (moderate frequency, MF) or three weeks (high frequency, HF) followed by a detraining period of nine weeks without any training. In both groups, maximal oxygen uptake (VO2max) was evaluated before training, at the 9th and 17th session and four days after the final 24th training session. In the detraining phase VO2max was evaluated after 12 days and thereafter every second week for eight weeks. Left ventricular echocardiography, carbon monoxide lung diffusion transfer factor, brachial artery flow mediated dilatation and vastus lateralis citrate maximal synthase activity was tested before and after training. Results The cardiovascular adaptation after HF training was delayed compared to training with MF. Four days after ending training the HF group showed no improvement (+3.0%, p = 0.126), whereas the MF group reached their highest VO2max with a 10.7% improvement (p<0.001: group difference p = 0.035). The HF group reached their highest VO2max (6.1% increase, p = 0.026) twelve days into the detraining period, compared to a concomitant reduction to 7.9% of VO2max (p<0.001) above baseline in the MF group (group difference p = 0.609). Conclusion Both HF and MF training of high-intensity aerobic exercise improves VO2max. The cardiovascular adaptation following a HF programme of high-intensity exercise is however delayed compared to MF training. Trial Registration ClinicalTrials.gov NCT00733941. PMID:24516645

  1. A novel femtosecond-gated, high-resolution, frequency-shifted shearing interferometry technique for probing pre-plasma expansion in ultra-intense laser experiments

    SciTech Connect

    Feister, S. Orban, C.; Nees, J. A.; Morrison, J. T.; Frische, K. D.; Chowdhury, E. A.; Roquemore, W. M.

    2014-11-15

    Ultra-intense laser-matter interaction experiments (>10{sup 18} W/cm{sup 2}) with dense targets are highly sensitive to the effect of laser “noise” (in the form of pre-pulses) preceding the main ultra-intense pulse. These system-dependent pre-pulses in the nanosecond and/or picosecond regimes are often intense enough to modify the target significantly by ionizing and forming a plasma layer in front of the target before the arrival of the main pulse. Time resolved interferometry offers a robust way to characterize the expanding plasma during this period. We have developed a novel pump-probe interferometry system for an ultra-intense laser experiment that uses two short-pulse amplifiers synchronized by one ultra-fast seed oscillator to achieve 40-fs time resolution over hundreds of nanoseconds, using a variable delay line and other techniques. The first of these amplifiers acts as the pump and delivers maximal energy to the interaction region. The second amplifier is frequency shifted and then frequency doubled to generate the femtosecond probe pulse. After passing through the laser-target interaction region, the probe pulse is split and recombined in a laterally sheared Michelson interferometer. Importantly, the frequency shift in the probe allows strong plasma self-emission at the second harmonic of the pump to be filtered out, allowing plasma expansion near the critical surface and elsewhere to be clearly visible in the interferograms. To aid in the reconstruction of phase dependent imagery from fringe shifts, three separate 120° phase-shifted (temporally sheared) interferograms are acquired for each probe delay. Three-phase reconstructions of the electron densities are then inferred by Abel inversion. This interferometric system delivers precise measurements of pre-plasma expansion that can identify the condition of the target at the moment that the ultra-intense pulse arrives. Such measurements are indispensable for correlating laser pre-pulse measurements

  2. Modeling secondary cancer risk following paediatric radiotherapy: a comparison of intensity modulated proton therapy and photon therapy

    NASA Astrophysics Data System (ADS)

    Shin, Naomi

    Proton radiotherapy is known to reduce the radiation dose delivered to normal healthy tissue compared to photon techniques. The increase in normal tissue sparing could result in fewer acute and late effects from radiation therapy. In this work proton therapy plans were created for patients previously treated using photon therapy. Intensity modulated proton therapy (IMPT) plans were planned using inverse planning in VarianRTM's Eclipse(TM) treatment planning system with a scanning proton beam model to the same relative biological effectiveness (RBE)-weighted prescription dose as the photon plan. Proton and photon plans were compared for target dose conformity and homogeneity, body volumes receiving 2 Gy and 5 Gy, integral dose, dose to normal tissues and second cancer risk. Secondary cancer risk was determined using two methods. The relative risk of secondary cancer was found using the method described by Nguyen et al. 1 by applying a linear relationship between integral dose and relative risk of secondary cancer. The second approach used Schneider et al. 's organ equivalent dose concept to describe the dose in the body and then calculate the excess absolute risk and cumulative risk for solid cancers in the body. IMPT and photon plans had similar target conformity and homogeneity. However IMPT plans had reduced integral dose and volumes of the body receiving low dose. Overall the risk of radiation induced secondary cancer was lower for IMPT plans compared to the corresponding photon plans with a reduction of ~36% using the integral dose model and ˜50% using the organ equivalent dose model. *Please refer to dissertation for footnotes.

  3. Cardiac Exposure in the Dynamic Conformal Arc Therapy, Intensity-Modulated Radiotherapy and Volumetric Modulated Arc Therapy of Lung Cancer

    PubMed Central

    Ming, Xin; Feng, Yuanming; Liu, Huan; Zhang, Ying; Zhou, Li; Deng, Jun

    2015-01-01

    Purpose To retrospectively evaluate the cardiac exposure in three cohorts of lung cancer patients treated with dynamic conformal arc therapy (DCAT), intensity-modulated radiotherapy (IMRT), or volumetric modulated arc therapy (VMAT) at our institution in the past seven years. Methods and Materials A total of 140 lung cancer patients were included in this institutional review board approved study: 25 treated with DCAT, 70 with IMRT and 45 with VMAT. All plans were generated in a same commercial treatment planning system and have been clinically accepted and delivered. The dose distribution to the heart and the effects of tumor laterality, the irradiated heart volume and the beam-to-heart distance on the cardiac exposure were investigated. Results The mean dose to the heart among all 140 plans was 4.5 Gy. Specifically, the heart received on average 2.3, 5.2 and 4.6 Gy in the DCAT, IMRT and VMAT plans, respectively. The mean heart doses for the left and right lung tumors were 4.1 and 4.8 Gy, respectively. No patients died with evidence of cardiac disease. Three patients (2%) with preexisting cardiac condition developed cardiac disease after treatment. Furthermore, the cardiac exposure was found to increase linearly with the irradiated heart volume while decreasing exponentially with the beam-to-heart distance. Conclusions Compared to old technologies for lung cancer treatment, modern radiotherapy treatment modalities demonstrated better heart sparing. But the heart dose in lung cancer radiotherapy is still higher than that in the radiotherapy of breast cancer and Hodgkin’s disease where cardiac complications have been extensively studied. With strong correlations of mean heart dose with beam-to-heart distance and irradiated heart volume, cautions should be exercised to avoid long-term cardiac toxicity in the lung cancer patients undergoing radiotherapy. PMID:26630566

  4. Passive coherent discriminator using phase diversity for the simultaneous measurement of frequency noise and intensity noise of a continuous-wave laser

    NASA Astrophysics Data System (ADS)

    Michaud-Belleau, V.; Bergeron, H.; Light, P. S.; Hébert, N. B.; Deschênes, J. D.; Luiten, A. N.; Genest, J.

    2016-10-01

    The frequency noise and intensity noise of a laser set the performance limits in many modern photonics applications and, consequently, must often be characterized. As lasers continue to improve, the measurement of these noises however becomes increasingly challenging. Current approaches for the characterization of very high-performance lasers often call for a second laser with equal or higher performance to the one that is to be measured, an incoherent interferometer having an extremely long delay-arm, or an interferometer that relies on an active device. These instrumental features can be impractical or problematic under certain experimental conditions. As an alternative, this paper presents an entirely passive coherent interferometer that employs an optical 90° hybrid coupler to perform in-phase and quadrature detection. We demonstrate the technique by measuring the frequency noise power spectral density of a highly-stable 192 THz (1560 nm) fiber laser over five frequency decades. Simultaneously, we are able to measure its relative intensity noise power spectral density and characterize the correlation between its amplitude noise and phase noise. We correct some common misconceptions through a detailed theoretical analysis and demonstrate the necessity to account for normal imperfections of the optical 90° hybrid coupler. We finally conclude that this passive coherent discriminator is suitable for reliable and simple noise characterization of highly-stable lasers, with bandwidth and dynamic range benefits but susceptibility to additive noise contamination.

  5. A low-frequency high-voltage rf-barrier-bunching system for high-intensity neutron source compressor rings

    SciTech Connect

    Hardek, T.W.; Ziomek, C.; Rees, D.

    1995-05-01

    A Los Alamos design for a 1-MW pulsed neutron source incorporates a ring utilizing an rf-barrier bunching system. This bunching concept allows uniform longitudinal beam distributions with low momentum spread. Bunching cavities are operated at the revolution frequency (1.5 MHz in this case) and each of the 2nd, 3rd, 4th, and 5th revolution frequency harmonics. Their effects combine to maintain a beam free gap in the longitudinal distribution of the accumulated beam. The cavities are driven by low-plate-resistance common-cathode configured retrode amplifiers incorporating local rf feedback. Additional adaptive feed-forward hardware is included to reduce the beam-induced bunching-gap voltages well below that achievable solely with rf feedback. Details of this system are presented along with a discussion of the various feed-back and feed-forward techniques incorporated.

  6. The road to clinical use of high-intensity focused ultrasound for liver cancer: technical and clinical consensus

    PubMed Central

    2013-01-01

    Clinical use of high-intensity focused ultrasound (HIFU) under ultrasound or MR guidance as a non-invasive method for treating tumors is rapidly increasing. Tens of thousands of patients have been treated for uterine fibroid, benign prostate hyperplasia, bone metastases, or prostate cancer. Despite the methods' clinical potential, the liver is a particularly challenging organ for HIFU treatment due to the combined effect of respiratory-induced liver motion, partial blocking by the rib cage, and high perfusion/flow. Several technical and clinical solutions have been developed by various groups during the past 15 years to compensate for these problems. A review of current unmet clinical needs is given here, as well as a consensus from a panel of experts about technical and clinical requirements for upcoming pilot and pivotal studies in order to accelerate the development and adoption of focused ultrasound for the treatment of primary and secondary liver cancer. PMID:25512859

  7. The road to clinical use of high-intensity focused ultrasound for liver cancer: technical and clinical consensus.

    PubMed

    Aubry, Jean-Francois; Pauly, Kim Butts; Moonen, Chrit; Haar, Gail Ter; Ries, Mario; Salomir, Rares; Sokka, Sham; Sekins, Kevin Michael; Shapira, Yerucham; Ye, Fangwei; Huff-Simonin, Heather; Eames, Matt; Hananel, Arik; Kassell, Neal; Napoli, Alessandro; Hwang, Joo Ha; Wu, Feng; Zhang, Lian; Melzer, Andreas; Kim, Young-Sun; Gedroyc, Wladyslaw M

    2013-01-01

    Clinical use of high-intensity focused ultrasound (HIFU) under ultrasound or MR guidance as a non-invasive method for treating tumors is rapidly increasing. Tens of thousands of patients have been treated for uterine fibroid, benign prostate hyperplasia, bone metastases, or prostate cancer. Despite the methods' clinical potential, the liver is a particularly challenging organ for HIFU treatment due to the combined effect of respiratory-induced liver motion, partial blocking by the rib cage, and high perfusion/flow. Several technical and clinical solutions have been developed by various groups during the past 15 years to compensate for these problems. A review of current unmet clinical needs is given here, as well as a consensus from a panel of experts about technical and clinical requirements for upcoming pilot and pivotal studies in order to accelerate the development and adoption of focused ultrasound for the treatment of primary and secondary liver cancer. PMID:25512859

  8. Optical pathology of human brain metastasis of lung cancer using combined resonance Raman and spatial frequency spectroscopies

    NASA Astrophysics Data System (ADS)

    Zhou, Yan; Liu, Cheng-hui; Pu, Yang; Cheng, Gangge; Zhou, Lixin; Chen, Jun; Zhu, Ke; Alfano, Robert R.

    2016-03-01

    Raman spectroscopy has become widely used for diagnostic purpose of breast, lung and brain cancers. This report introduced a new approach based on spatial frequency spectra analysis of the underlying tissue structure at different stages of brain tumor. Combined spatial frequency spectroscopy (SFS), Resonance Raman (RR) spectroscopic method is used to discriminate human brain metastasis of lung cancer from normal tissues for the first time. A total number of thirty-one label-free micrographic images of normal and metastatic brain cancer tissues obtained from a confocal micro- Raman spectroscopic system synchronously with examined RR spectra of the corresponding samples were collected from the identical site of tissue. The difference of the randomness of tissue structures between the micrograph images of metastatic brain tumor tissues and normal tissues can be recognized by analyzing spatial frequency. By fitting the distribution of the spatial frequency spectra of human brain tissues as a Gaussian function, the standard deviation, σ, can be obtained, which was used to generate a criterion to differentiate human brain cancerous tissues from the normal ones using Support Vector Machine (SVM) classifier. This SFS-SVM analysis on micrograph images presents good results with sensitivity (85%), specificity (75%) in comparison with gold standard reports of pathology and immunology. The dual-modal advantages of SFS combined with RR spectroscopy method may open a new way in the neuropathology applications.

  9. [Intensity-modulated radiotherapy of head and neck cancers. Dose constraint for spinal cord and brachial plexus].

    PubMed

    Boisselier, P; Racadot, S; Thariat, J; Graff, P; Pointreau, Y

    2016-10-01

    Given the ballistic opportunities it offers, intensity-modulated radiotherapy has emerged as the gold standard treatment for head and neck cancers. Protection of organs at risk is one of the objectives of optimization during the planning process. The compliance of dose constraints to the nervous system must be prioritized over all others. To avoid complications, it is recommended to respect a maximum dose of 50Gy to the spinal cord, and 60Gy to the brachial plexus using conventional fractionation of 2Gy per fraction. These constraints can be adapted depending on the clinical situation; they will probably be refocused by the follow-up of the IMRT studies. PMID:27614529

  10. [Intensity-modulated radiotherapy of head and neck cancers. Dose constraint for spinal cord and brachial plexus].

    PubMed

    Boisselier, P; Racadot, S; Thariat, J; Graff, P; Pointreau, Y

    2016-10-01

    Given the ballistic opportunities it offers, intensity-modulated radiotherapy has emerged as the gold standard treatment for head and neck cancers. Protection of organs at risk is one of the objectives of optimization during the planning process. The compliance of dose constraints to the nervous system must be prioritized over all others. To avoid complications, it is recommended to respect a maximum dose of 50Gy to the spinal cord, and 60Gy to the brachial plexus using conventional fractionation of 2Gy per fraction. These constraints can be adapted depending on the clinical situation; they will probably be refocused by the follow-up of the IMRT studies.

  11. Frequency of mutations in mismatch repair genes in a population-based study of women with ovarian cancer

    PubMed Central

    Pal, T; Akbari, M R; Sun, P; Lee, J-H; Fulp, J; Thompson, Z; Coppola, D; Nicosia, S; Sellers, T A; McLaughlin, J; Risch, H A; Rosen, B; Shaw, P; Schildkraut, J; Narod, S A

    2012-01-01

    Background: Mutations in genes for hereditary non-polyposis colorectal cancer (HNPCC) in ovarian cancer patients remains poorly defined. We sought to estimate the frequency and characteristics of HNPCC gene mutations in a population-based sample of women with epithelial ovarian cancer. Methods: The analysis included 1893 women with epithelial ovarian cancer ascertained from three population-based studies. Full-germline DNA sequencing of the coding regions was performed on three HNPCC genes, MLH1, MSH2 and MSH6. Collection of demographic, clinical and family history information was attempted in all women. Results: Nine clearly pathogenic mutations were identified, including five in MSH6, two each in MLH1 and MSH2. In addition, 28 unique predicted pathogenic missense variants were identified in 55 patients. Pathogenic mutation carriers had an earlier mean age at diagnosis of ovarian cancer, overrepresentation of cancers with non-serous histologies and a higher number of relatives with HNPCC-related cancers. Conclusions: Our findings suggest that fewer than 1% of women with ovarian cancer harbour a germline mutation in the HNPCC genes, with overrepresentation of MSH6 mutations. This represents a lower-range estimate due to the large number of predicted pathogenic variants in which pathogenicity could not definitively be determined. Identification of mismatch repair gene mutations has the potential to impact screening and treatment decisions in these women. PMID:23047549

  12. Dose Volume Histogram (DVH) Analysis in Intensity Modulation Radiation Therapy (IMRT) Treatments for Prostate Cancers

    NASA Astrophysics Data System (ADS)

    Pyakuryal, Anil

    2009-05-01

    Studies have shown that as many as 8 out of 10 men had prostate cancer by age 80.Prostate cancer begins with small changes (prostatic intraepithelial neoplasia(PIN)) in size and shape of prostate gland cells,known as prostate adenocarcinoma.With advent in technology, prostate cancer has been the most widely used application of IMRT with the longest follow-up periods.Prostate cancer fits the ideal target criteria for IMRT of adjacent sensitive dose-limiting tissue (rectal, bladder).A retrospective study was performed on 10 prostate cancer patients treated with radiation to a limited pelvic field with a standard 4 field arrangements at dose 45 Gy, and an IMRT boost field to a total isocenter dose of 75 Gy.Plans were simulated for 4 field and the supplementary IMRT treatments with proposed dose delivery at 1.5 Gy/fraction in BID basis.An automated DVH analysis software, HART (S. Jang et al., 2008,Med Phys 35,p.2812)was used to perform DVH assessments in IMRT plans.A statistical analysis of dose coverage at targets in prostate gland and neighboring critical organs,and the plan indices(homogeneity, conformality etc) evaluations were also performed using HART extracted DVH statistics.Analyzed results showed a better correlation with the proposed outcomes (TCP, NTCP) of the treatments.

  13. Intensity/frequency indicator for detection in space the high values of the incident solar or laser optical radiation in comparison with the appropriate maximum permissible exposure

    NASA Astrophysics Data System (ADS)

    Tsitomeneas, S.; Petropoulos, B.

    2001-08-01

    The solar or laser optical radiation impact to humans in space depends on the intensity, on the exposure type (direct or indirect) & duration and on the matching of radiation wavelength to tissue characteristics. The main protection factor in space is the application of exposure limits. This paper describes the main biological optical interaction parameters, the optical exposure hazards and the development of a small active lightweight indicator, with output beeper rate depended to the ratio of optical irradiance / exposure limit. The indicator may be used as warning element on the side of helmets, goggles, spectacles, etc, with low power consumption. Electronically the indicator is an intensity/frequency converter, based on the value of the ratio of exposure / exposure limits, with audio & light beepers like the indication output of the ionizing (radioactive) radiation monitors.

  14. Intensity/frequency indicator for detection in space: the high values of the incident solar or laser optical radiation in comparison with the appropriate maximum permissible exposure.

    PubMed

    Tsitomeneas, S; Petropoulos, B

    2001-01-01

    The solar or laser optical radiation impact to humans in space depends on the intensity, on the exposure type (direct or indirect) & duration and on the matching of radiation wavelength to tissue characteristics. The main protection factor in space is the application of exposure limits. This paper describes the main biological optical interaction parameters, the optical exposure hazards and the development of a small active lightweight indicator, with output beeper rate depended to the ratio of optical irradiance/exposure limit. The indicator may be used as warning element on the side of helmets, goggles, spectacles, etc, with low power consumption. Electronically the indicator is an intensity/frequency converter, based on the value of the ratio of exposure/exposure limits, with audio & light beepers like the indication output of the ionizing (radioactive) radiation monitors.

  15. Effects of an intense, high-frequency laser field on bound states in Ga1 - xInxNyAs1 - y/GaAs double quantum well.

    PubMed

    Ungan, Fatih; Yesilgul, Unal; Sakiroğlu, Serpil; Kasapoglu, Esin; Erol, Ayse; Arikan, Mehmet Cetin; Sarı, Huseyin; Sökmen, Ismail

    2012-10-31

    Within the envelope function approach and the effective-mass approximation, we have investigated theoretically the effect of an intense, high-frequency laser field on the bound states in a GaxIn1 - xNyAs1 - y/GaAs double quantum well for different nitrogen and indium mole concentrations. The laser-dressed potential, bound states, and squared wave functions related to these bound states in Ga1 - xInxNyAs1 - y/GaAs double quantum well are investigated as a function of the position and laser-dressing parameter. Our numerical results show that both intense laser field and nitrogen (indium) incorporation into the GaInNAs have strong influences on carrier localization.

  16. Frequency and intensity dependence of the sub-band-gap features observed in the surface photovoltage spectrum of semi-insulating GaAs

    NASA Astrophysics Data System (ADS)

    Sharma, T. K.; Kumar, Shailendra; Rustagi, K. C.

    2002-11-01

    Surface photovoltage spectroscopy studies on thick semi-insulating GaAs wafers are reported in the range 850-950 nm using the chopped light geometry. We observed some interesting sharp features in the sub-band-gap of SI-GaAs, which were reported recently [Appl. Phys. Lett. 79, 1715(2001); Rev. Sci. Instrum. 73, 1835 (2002)]. In this article, we present the dependence of these features on the chopping frequency and the source intensity. The intensity variation in the above-band-gap region and for the A peak (898 nm) in the sub-band-gap region could be fitted with single component while it is necessary to consider more than one component to fit the data for the Q peak (887 nm) in the sub-band-gap region. A model consistent with the observed features is also proposed.

  17. Stability, Bistability, and Critical Thresholds in Fire-prone Forested Landscapes: How Frequency and Intensity of Disturbance Interact and Influence Forest Cover

    NASA Astrophysics Data System (ADS)

    Miller, A. D.

    2015-12-01

    Many aspects of disturbance processes can have large impacts on the composition of plant communities, and associated changes in land cover type in turn have biogeochemical feedbacks to climate. In particular, changes to disturbance regimes can potentially change the number and stability of equilibrial states, and plant community states can differ dramatically in their carbon (C) dynamics, energy balance, and hydrology. Using the Klamath region of northern California as a model system, we present a theoretical analysis of how changes to climate and associated fire dynamics can disrupt high-carbon, long-lived conifer forests and replace them with shrub-chaparral communities that have much lower biomass and are more pyrogenic. Specifically, we develop a tractable model of plant community dynamics, structured by size class, life-history traits, lottery-type competition, and species-specific responses to disturbance. We assess the stability of different states in terms of disturbance frequency and intensity, and quantitatively partition long-term low-density population growth rates into mechanisms that influence critical transitions from stable to bistable behavior. Our findings show how different aspects of disturbance act and interact to control competitive outcomes and stable states, hence ecosystem-atmosphere C exchange. Forests tend to dominate in low frequency and intensity regimes, while shrubs dominate at high fire frequency and intensity. In other regimes, the system is bistable, and the fate of the system depends both on initial conditions and random chance. Importantly, the system can cross a critical threshold where hysteresis prevents easy return to the prior forested state. We conclude that changes in disturbance-recovery dynamics driven by projected climate change can shift this system away from forest dominated in the direction of shrub-dominated landscape. This will result in a large net C release from the landscape, and alter biophysical ecosystem

  18. Translating aboveground cosmic-ray neutron intensity to high-frequency soil moisture profiles at sub-kilometer scale

    NASA Astrophysics Data System (ADS)

    Rosolem, R.; Hoar, T.; Arellano, A.; Anderson, J. L.; Shuttleworth, W. J.; Zeng, X.; Franz, T. E.

    2014-11-01

    Above-ground cosmic-ray neutron measurements provide an opportunity to infer soil moisture at the sub-kilometer scale. Initial efforts to assimilate those measurements have shown promise. This study expands such analysis by investigating (1) how the information from aboveground cosmic-ray neutrons can constrain the soil moisture at distinct depths simulated by a land surface model, and (2) how changes in data availability (in terms of retrieval frequency) impact the dynamics of simulated soil moisture profiles. We employ ensemble data assimilation techniques in a "nearly-identical twin" experiment applied at semi-arid shrubland, rainfed agricultural field, and mixed forest biomes in the USA. The performance of the Noah land surface model is compared with and without assimilation of observations at hourly intervals, as well as every 2 days. Synthetic observations of aboveground cosmic-ray neutrons better constrain the soil moisture simulated by Noah in root-zone soil layers (0-100cm), despite the limited measurement depth of the sensor (estimated to be 12-20cm). The ability of Noah to reproduce a "true" soil moisture profile is remarkably good, regardless of the frequency of observations at the semi-arid site. However, soil moisture profiles are better constrained when assimilating synthetic cosmic-ray neutron observations hourly rather than every 2 days at the cropland and mixed forest sites. This indicates potential benefits for hydrometeorological modeling when soil moisture measurements are available at a relatively high frequency. Moreover, differences in summertime meteorological forcing between the semi-arid site and the other two sites may indicate a possible controlling factor to soil moisture dynamics in addition to differences in soil and vegetation properties.

  19. Assessing risk of thyroid cancer using resonance-frequency based electrical impedance measurements

    NASA Astrophysics Data System (ADS)

    Zheng, Bin; Tublin, Mitchell E.; Lederman, Dror; Klym, Amy H.; Brown, Erica D.; Gur, David

    2011-03-01

    The incidence of thyroid cancer has risen faster than many malignancies and has nearly doubled in the USA over the past 30 years. Palpable nodules and subclinical nodules detected by imaging are found in a large percentage of the USA population. Most of these (.>95%) are fortunately benign. This vast reservoir of nodules makes the detection and diagnosis of thyroid cancer a diagnostic dilemma. Ultrasound guided Fine Needle Aspiration Biopsy (FNAB) is excellent for triaging patients but up to 25% of FNABs are inconclusive. As a result, definitive diagnosis is often only possible with a diagnostic lobectomy; many thousands of these are performed in the USA annually for ultimately benign disease. It would be extremely beneficial if we could develop a non-invasive procedure that could assist the diagnostician in reliably predicting the likelihood of malignancy of otherwise indeterminate thyroid nodules, thereby reducing the number of these "exploratory/diagnostic" lobectomies performed under general anesthesia. Electrical Impedance Spectroscopy (EIS) was considered as a possible approach to address this problem. However, the diagnostic accuracy of EIS is too low for routine clinical use to date. In our group, we developed a substantially modified technology termed Resonance-frequency Electrical Impedance Spectroscopy (REIS), which yields usable information for classifying risk of having breast abnormalities. We preliminarily applied REIS to measure signals on participants having thyroid nodules aiming to assess whether we can assist in improving diagnosis of indeterminate thyroid nodules. In this study we present a new multi-probe based REIS device specifically designed for the assessment of indeterminate thyroid nodules. Our preliminary assessment presented here demonstrates the feasibility of using this proposed REIS device in a busy tertiary care center.

  20. Cancer risk assessment of extremely low frequency electric and magnetic fields: a critical review of methodology.

    PubMed Central

    McCann, J

    1998-01-01

    This review provides a discussion of cancer risk assessment methodology pertinent to developing a strategy for extremely low frequency electric and magnetic fields (EMF). Approaches taken for chemical agents or ionizing radiation in six key topic areas are briefly reviewed, and then those areas are examined from the perspective of EMF, identifying issues to be addressed in developing a risk assessment strategy. The following recommendations are offered: 1) risk assessment should be viewed as an iterative process that informs an overall judgment as to health risk and consists of a complex of related activities incorporating both positive and negative data, tumor and nontumor end points, and human and nonhuman sources of information; 2) a hazard identification resulting in a conclusion of weak or null effects, such as may be associated with EMF, will need to assign significant weight to animal cancer bioassays conducted under defined exposure conditions as well as to human epidemiologic studies; 3) a default factor to account for possible age differences in sensitivity to carcinogenesis should be included in an EMF risk assessment; 4) lack of evidence of dose response and the apparent lack of DNA reactivity of EMF suggest that a safety (or uncertainty) factor or margin of exposure type of risk characterization may be most appropriate; and 5) an EMF risk assessment should permit at least tentative conclusions to be reached as to the limits of carcinogenic risk from exposure to EMF, and should also define an efficient research agenda aimed at clarifying uncertainties appropriate to a more complete assessment. PMID:9799185

  1. Measurements of ion cyclotron range of frequencies mode converted wave intensity with phase contrast imaging in Alcator C-Mod and comparison with full-wave simulations

    NASA Astrophysics Data System (ADS)

    Tsujii, N.; Porkolab, M.; Bonoli, P. T.; Lin, Y.; Wright, J. C.; Wukitch, S. J.; Jaeger, E. F.; Green, D. L.; Harvey, R. W.

    2012-08-01

    Radio frequency waves in the ion cyclotron range of frequencies (ICRF) are widely used to heat tokamak plasmas. In ICRF heating schemes involving multiple ion species, the launched fast waves convert to ion cyclotron waves or ion Bernstein waves at the two-ion hybrid resonances. Mode converted waves are of interest as actuators to optimise plasma performance through current drive and flow drive. In order to describe these processes accurately in a realistic tokamak geometry, numerical simulations are essential, and it is important that these codes be validated against experiment. In this study, the mode converted waves were measured using a phase contrast imaging technique in D-H and D-3He plasmas. The measured mode converted wave intensity in the D-3He mode conversion regime was found to be a factor of ˜50 weaker than the full-wave predictions. The discrepancy was reduced in the hydrogen minority heating regime, where mode conversion is weaker.

  2. Sheet beam model for intense space-charge: with application to Debye screening and the distribution of particle oscillation frequencies in a thermal equilibrium beam

    SciTech Connect

    Lund, Steven M.; Friedman, Alex; Bazouin, Guillaume

    2011-01-10

    A one-dimensional Vlasov-Poisson model for sheet beams is reviewed and extended to provide a simple framework for analysis of space-charge effects. Centroid and rms envelope equations including image charge effects are derived and reasonable parameter equivalences with commonly employed 2D transverse models of unbunched beams are established. This sheet beam model is then applied to analyze several problems of fundamental interest. A sheet beam thermal equilibrium distribution in a continuous focusing channel is constructed and shown to have analogous properties to two- d three-dimensional thermal equilibrium models in terms of the equilibrium structure and Deybe screening properties. The simpler formulation for sheet beams is exploited to explicitly calculate the distribution of particle oscillation frequencies within a thermal equilibrium beam. It is shown that as space-charge intensity increases, the frequency distribution becomes broad, suggesting that beams with strong space-charge can have improved stability.

  3. Reply to Comment on ‘Roles of interbasin frequency changes in the poleward shifts of maximum intensity location of tropical cyclones’

    NASA Astrophysics Data System (ADS)

    Moon, Il-Ju; Kim, Sung-Hun; Klotzbach, Phil; Chan, Johnny C. L.

    2016-06-01

    Recently a pronounced global poleward shift in the latitude at which the maximum intensities of tropical cyclones (TC) occur has been identified. Moon et al (2015 Environ. Res. Lett. 10 104004) reported that the poleward migration is significantly influenced by changes in interbasin frequency. These frequency changes are a larger contributor to the poleward shift than the intrabasin migration component. The strong role of interbasin frequency changes in the poleward migration also suggest that the poleward trend could be changed to an opposite equatorward trend in the future due to multi-decadal variability that significantly impacts Northern Hemisphere TC frequency. In the accompanying comment, Kossin et al (2016 Environ. Res. Lett. 11 068001) questioned the novelty and robustness of our results by raising issues associated with subsampling, contributions from some basins to poleward migration, and data dependency. Here, we explain the originality and importance of our main findings, which are different from those of Kossin et al (2014 Nature 509 349–52) and reaffirm that our conclusions are maintained regardless of the issues that were raised.

  4. Choosing an Intensity-Modulated Radiation Therapy Technique in the Treatment of Head-and-Neck Cancer

    SciTech Connect

    Lee, Nancy . E-mail: leen2@mskcc.org; Mechalakos, James; Puri, Dev R.; Hunt, Margie

    2007-08-01

    Purpose: With the emerging use of intensity-modulated radiation therapy (IMRT) in the treatment of head-and-neck cancer, selection of technique becomes a critical issue. The purpose of this article is to establish IMRT guidelines for head-and-neck cancer at a given institution. Methods and Materials: Six common head-and-neck cancer cases were chosen to illustrate the points that must be considered when choosing between split-field (SF) IMRT, in which the low anterior neck (LAN) is treated with an anterior field, and the extended whole-field (EWF) IMRT in which the LAN is included with the IMRT fields. For each case, the gross tumor, clinical target, and planning target volumes and the surrounding critical normal tissues were delineated. Subsequently, the SF and EWF IMRT plans were compared using dosimetric parameters from dose-volume histograms. Results: Target coverage and doses delivered to the critical normal structures were similar between the two different techniques. Cancer involving the nasopharynx and oropharynx are best treated with the SF IMRT technique to minimize the glottic larynx dose. The EWF IMRT technique is preferred in situations in which the glottic larynx is considered as a target, i.e., cancer of the larynx, hypopharynx, and unknown head-and-neck primary. When the gross disease extends inferiorly and close to the glottic larynx, EWF IMRT technique is also preferred. Conclusion: Depending on the clinical scenario, different IMRT techniques and guidelines are suggested to determine a preferred IMRT technique. We found that having this treatment guideline when treating these tumors ensures a smoother flow for the busy clinic.

  5. Bone Marrow Sparing in Intensity Modulated Proton Therapy for Cervical Cancer: Efficacy and Robustness under Range and Setup Uncertainties

    PubMed Central

    Dinges, Eric; Felderman, Nicole; McGuire, Sarah; Gross, Brandie; Bhatia, Sudershan; Mott, Sarah; Buatti, John; Wang, Dongxu

    2015-01-01

    Background and Purpose This study evaluates the potential efficacy and robustness of functional bone marrow sparing (BMS) using intensity-modulated proton therapy (IMPT) for cervical cancer, with the goal of reducing hematologic toxicity. Material and Methods IMPT plans with prescription dose of 45 Gy were generated for ten patients who have received BMS intensity-modulated x-ray therapy (IMRT). Functional bone marrow was identified by 18F-flourothymidine positron emission tomography. IMPT plans were designed to minimize the volume of functional bone marrow receiving 5–40 Gy while maintaining similar target coverage and healthy organ sparing as IMRT. IMPT robustness was analyzed with ±3% range uncertainty errors and/or ±3mm translational setup errors in all three principal dimensions. Results In the static scenario, the median dose volume reductions for functional bone marrow by IMPT were: 32% for V5GY, 47% for V10Gy, 54% for V20Gy, and 57% for V40Gy, all with p<0.01 compared to IMRT. With assumed errors, even the worst-case reductions by IMPT were: 23% for V5Gy, 37% for V10Gy, 41% for V20Gy, and 39% for V40Gy, all with p<0.01. Conclusions The potential sparing of functional bone marrow by IMPT for cervical cancer is significant and robust under realistic systematic range uncertainties and clinically relevant setup errors. PMID:25981130

  6. Intensity-Modulated Radiation Therapy for the Treatment of Squamous Cell Anal Cancer With Para-aortic Nodal Involvement

    SciTech Connect

    Hodges, Joseph C.; Das, Prajnan; Eng, Cathy; Reish, Andrew G.; Beddar, A. Sam; Delclos, Marc E.; Krishnan, Sunil; Crane, Christopher H.

    2009-11-01

    Purpose: To determine the rates of toxicity, locoregional control, distant control, and survival in anal cancer patients with para-aortic nodal involvement, treated with intensity-modulated radiotherapy (IMRT) and concurrent chemotherapy at a single institution. Methods and Materials: Between 2001 and 2007, 6 patients with squamous cell anal cancer and para-aortic nodal involvement were treated with IMRT and concurrent infusional 5-fluorouracil and cisplatin. The primary tumor was treated with a median dose of 57.5 Gy (range, 54-60 Gy), involved para-aortic, pelvic, and inguinal lymph nodes were treated with a median dose of 55 Gy (range, 50.5-55 Gy), and noninvolved nodal regions were treated with a median dose of 45 Gy (range, 43.5-45 Gy). Results: After a median follow-up of 25 months, none of the patients had a recurrence at the primary tumor, pelvic/inguinal nodes, or para-aortic nodes, whereas 2 patients developed distant metastases to the liver. Four of the 6 patients are alive. The 3-year actuarial locoregional control, distant control, and overall survival rates were 100%, 56%, and 63%, respectively. Four of the 6 patients developed Grade 3 acute gastrointestinal toxicity during chemoradiation. Conclusions: Intensity-modulated radiotherapy and concurrent chemotherapy could potentially serve as definitive therapy in anal cancer patients with para-aortic nodal involvement. Adjuvant chemotherapy may be indicated in these patients, as demonstrated by the distant failure rates. These patients need to be followed carefully because of the potential for treatment-related toxicities.

  7. A Phase II Trial of Arc-Based Hypofractionated Intensity-Modulated Radiotherapy in Localized Prostate Cancer

    SciTech Connect

    Lock, Michael; Best, Lara; Wong, Eugene; Bauman, Glenn; D'Souza, David; Venkatesan, Varagur; Sexton, Tracy; Ahmad, Belal; Izawa, Jonathan; Rodrigues, George

    2011-08-01

    Purpose: To evaluate acute and late genitourinary (GU) and gastrointestinal (GI) toxicity and biochemical control of hypofractionated, image-guided (fiducial markers or ultrasound guidance), simplified intensity-modulated arc therapy for localized prostate cancer. Methods and Materials: This Phase II prospective clinical trial for T1a-2cNXM0 prostate cancer enrolled 66 patients who received 63.2 Gy in 20 fractions over 4 weeks. Fiducial markers were used for image guidance in 30 patients and daily ultrasound for the remainder. Toxicity was scored according to the National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0. Results: Median follow-up was 36 months. Acute Phase Grade 2 and 3 toxicity was 34% and 9% for GU vs. 25% and 10% for GI symptoms. One Grade 4 acute GI toxicity occurred in a patient with unrecognized Crohn's disease. Late Grade 2 and 3 toxicity for GU was 14% and 5%, and GI toxicity was 25% and 3%. One late GI Grade 4 toxicity was observed in a patient with significant comorbidities (anticoagulation, vascular disease). Acute GI toxicity {>=}Grade 2 was shown to be a predictor for late toxicity Grade {>=}2 (p < 0.001). The biochemical disease-free survival at 3 years was 95%. Conclusions: Hypofractionated simplified intensity-modulated arc therapy radiotherapy given as 63.2 Gy in 20 fractions demonstrated promising biochemical control rates; however, higher rates of acute Grade 3 GU and GI toxicity and higher late Grade 2 GU and GI toxicity were noted. Ongoing randomized controlled trials should ultimately clarify issues regarding patient selection and the true rate of severe toxicity that can be directly attributed to hypofractionated radiotherapy.

  8. Advances in the Measurement of CO2 using Swept-Frequency, Intensity-Modulated, Continuous-Wave Laser Absorption Spectroscopy

    NASA Astrophysics Data System (ADS)

    Harrison, F. W.; Ismail, S.; Nehrir, A. R.; Lin, B.; Browell, E. V.; McGregor, D.; Kooi, S. A.; Dobler, J. T.; Collins, J. E.; Choi, Y.; Obland, M. D.

    2013-12-01

    Understanding the carbon balance in the environment is critical to projections of the future evolution of the Earth's climate. Large uncertainties in the forecast of future atmospheric carbon dioxide (CO2) concentrations and carbon sources and sinks persist due to the limited set of observations from the current network of in-situ and surface measurements. Global, spaceborne measurements of atmospheric CO2 can reduce these uncertainties. Feasibility studies of space column CO2 mixing ratio (XCO2) measurements using laser remote sensing have been initiated by NASA. The XCO2 measurement requires the simultaneous measurement of both CO2 and O2 number density columns weighted to the near surface and that biases from aerosols or clouds be minimized. This paper discusses the latest flight test results from the Multi-Functional Fiber Laser Lidar (MFLL), a laser absorption spectrometer (LAS) system under development by Exelis, Inc. in partnership with NASA Langley Research Center (LaRC) for the ASCENDS mission. The MFLL uses Intensity-Modulated, Continuous-Wave narrow-band lasers operated on and off of a CO2 absorption feature to measure the differential absorption of atmospheric CO2. By simultaneously modulating the laser beam with range-encoded signals, the retrieval of column CO2 concentrations to the Earth's surface, to the top of optically thick clouds, and through optically thin clouds is enabled. In early 2013, MFLL participated in an intensive flight campaign designed to flight test three ASCENDS prototype instruments onboard the NASA DC-8. The campaign consisted of nine flights of the NASA DC-8 over surfaces of varying reflectivity and in atmospheric conditions including clouds. Here we report on the evaluation of MFLL remote measurements of CO2 column concentrations as compared to the CO2 columns derived from contemporaneous airborne in situ CO2 profile measurements. This paper describes the modulation techniques employed by MFLL, presents algorithms for

  9. Dynamic interference in the photoionization of He by coherent intense high-frequency laser pulses: Direct propagation of the two-electron wave packets on large spatial grids

    NASA Astrophysics Data System (ADS)

    Artemyev, Anton N.; Müller, Anne D.; Hochstuhl, David; Cederbaum, Lorenz S.; Demekhin, Philipp V.

    2016-04-01

    The direct ionization of the helium atom by intense coherent high-frequency short laser pulses is investigated theoretically from first principles. To this end, we solve numerically the time-dependent Schrödinger equation for the two-electron wave packet and its interaction with the linearly polarized pulse by the efficient time-dependent restricted-active-space configuration-interaction method (TD-RASCI). In particular, we consider photon energies which are nearly resonant for the 1 s →2 p excitation in the He+ ion. Thereby, we investigate the dynamic interference of the photoelectrons of the same kinetic energy emitted at different times along the pulse in the two-electron system. In order to enable observation of the dynamic interference in the computed spectrum, the electron wave packets were propagated on large spatial grids over long times. The computed photoionization spectra of He exhibit pronounced interference patterns the complexity of which increases with the decrease of the photon energy detuning and with the increase of the pulse intensity. Our numerical results pave the way for experimental verification of the dynamic interference effect at presently available high-frequency laser pulse sources.

  10. Self-rated measure of pain frequency, intensity, and burden: psychometric properties of a new instrument for the assessment of pain

    PubMed Central

    dela Cruz, Adriane M.; Bernstein, Ira H.; Greer, Tracy L.; Walker, Robrina; Rethorst, Chad D.; Grannemann, Bruce; Carmody, Thomas; Trivedi, Madhukar H.

    2014-01-01

    Background A brief, self-administered measurement of pain frequency, intensity, and burden is desirable in both research and clinical settings. We describe the development and initial psychometric properties of a new instrument, the Pain Frequency, Intensity, and Burden Scale (P-FIBS). Methods The P-FIBS was administered to all participants (N=302) with psychostimulant use disorders in the National Institute on Drug Abuse Clinical Trials Network’s STRIDE (Stimulant Reduction Intervention using Dose Exercise) multisite trial. Results The four items on the P-FIBS demonstrate high item-total correlations (range 0.70–0.85) with a high Cronbach’s alpha (0.90). The P-FIBS demonstrated a strong negative correlation with the bodily pain sub-score of the Short Form Health Survey (r=−0.76, p<0.0001) and did not correlate with a measure of cocaine (r=0.09, p=0.12) or methamphetamine (r=−0.06, p=0.33) craving. Conclusions The P-FIBS demonstrates good psychometric properties. This brief measure can be used to assess pain in research settings or as a screen in clinical settings. Further research is needed to assess the measure’s sensitivity to change with treatment. PMID:25194231

  11. High Intensity Focused Ultrasound versus Brachytherapy for the Treatment of Localized Prostate Cancer: A Matched-Pair Analysis.

    PubMed

    Aoun, Fouad; Limani, Ksenija; Peltier, Alexandre; Marcelis, Quentin; Zanaty, Marc; Chamoun, Alexandre; Vanden Bossche, Marc; Roumeguère, Thierry; van Velthoven, Roland

    2015-01-01

    Purpose. To evaluate postoperative morbidity and long term oncologic and functional outcomes of high intensity focused ultrasound (HIFU) compared to brachytherapy for the treatment of localized prostate cancer. Material and Methods. Patients treated by brachytherapy were matched 1 : 1 with patients who underwent HIFU. Differences in postoperative complications across the two groups were assessed using Wilcoxon's rank-sum or χ (2) test. Kaplan-Meier curves, log-rank tests, and Cox regression models were constructed to assess differences in survival rates between the two groups. Results. Brachytherapy was significantly associated with lower voiding LUTS and less frequent acute urinary retention (p < 0.05). Median oncologic follow-up was 83 months (13-123 months) in the HIFU cohort and 44 months (13-89 months) in the brachytherapy cohort. Median time to achieve PSA nadir was statistically shorter in the HIFU. Biochemical recurrence-free survival rate was significantly higher in the brachytherapy cohort compared to HIFU cohort (68.5% versus 53%, p < 0.05). No statistically significant difference in metastasis-free, cancer specific, and overall survivals was observed between the two groups. Conclusion. HIFU and brachytherapy are safe with no significant difference in cancer specific survival on long term oncologic follow-up. Nonetheless, a randomized controlled trial is needed to confirm these results. PMID:26357511

  12. High Intensity Focused Ultrasound versus Brachytherapy for the Treatment of Localized Prostate Cancer: A Matched-Pair Analysis

    PubMed Central

    Aoun, Fouad; Limani, Ksenija; Peltier, Alexandre; Marcelis, Quentin; Zanaty, Marc; Chamoun, Alexandre; Vanden Bossche, Marc; Roumeguère, Thierry; van Velthoven, Roland

    2015-01-01

    Purpose. To evaluate postoperative morbidity and long term oncologic and functional outcomes of high intensity focused ultrasound (HIFU) compared to brachytherapy for the treatment of localized prostate cancer. Material and Methods. Patients treated by brachytherapy were matched 1 : 1 with patients who underwent HIFU. Differences in postoperative complications across the two groups were assessed using Wilcoxon's rank-sum or χ2 test. Kaplan-Meier curves, log-rank tests, and Cox regression models were constructed to assess differences in survival rates between the two groups. Results. Brachytherapy was significantly associated with lower voiding LUTS and less frequent acute urinary retention (p < 0.05). Median oncologic follow-up was 83 months (13–123 months) in the HIFU cohort and 44 months (13–89 months) in the brachytherapy cohort. Median time to achieve PSA nadir was statistically shorter in the HIFU. Biochemical recurrence-free survival rate was significantly higher in the brachytherapy cohort compared to HIFU cohort (68.5% versus 53%, p < 0.05). No statistically significant difference in metastasis-free, cancer specific, and overall survivals was observed between the two groups. Conclusion. HIFU and brachytherapy are safe with no significant difference in cancer specific survival on long term oncologic follow-up. Nonetheless, a randomized controlled trial is needed to confirm these results. PMID:26357511

  13. Synergistic ablation of liver tissue and liver cancer cells with high-intensity focused ultrasound and ethanol.

    PubMed

    Hoang, Nguyen H; Murad, Hakm Y; Ratnayaka, Sithira H; Chen, Chong; Khismatullin, Damir B

    2014-08-01

    We investigated the combined effect of ethanol and high-intensity focused ultrasound (HIFU), first, on heating and cavitation bubble activity in tissue-mimicking phantoms and porcine liver tissues and, second, on the viability of HepG2 liver cancer cells. Phantoms or porcine tissues were injected with ethanol and then subjected to HIFU at acoustic power ranging from 1.2 to 20.5 W (HIFU levels 1-7). Cavitation events and the temperature around the focal zone were measured with a passive cavitation detector and embedded type K thermocouples, respectively. HepG2 cells were subjected to 4% ethanol solution in growth medium (v/v) just before the cells were exposed to HIFU at 2.7, 8.7 or 12.0 W for 30 s. Cell viability was measured 2, 24 and 72 h post-treatment. The results indicate that ethanol and HIFU have a synergistic effect on liver cancer ablation as manifested by greater temperature rise and lesion volume in liver tissues and reduced viability of liver cancer cells. This effect is likely caused by reduction of the cavitation threshold in the presence of ethanol and the increased rate of ethanol diffusion through the cell membrane caused by HIFU-induced streaming, sonoporation and heating.

  14. Determination of the allelic frequencies of an L-myc and a p53 polymorphism in human lung cancer.

    PubMed

    Weston, A; Ling-Cawley, H M; Caporaso, N E; Bowman, E D; Hoover, R N; Trump, B F; Harris, C C

    1994-04-01

    The L-myc and p53 genes have been implicated in lung cancer. Both of these genes have restriction fragment length polymorphisms (RFLPs) that could account for differential expression or activity of variant forms. An EcoRI restriction site in the L-myc gene was previously reported to be a predictor of poor prognosis in Japanese lung cancer patients. There are several RFLPs in the p53 gene. In exon 4 there is a polymorphism that codes for either an arginine or proline residue at codon 72. We previously reported the frequency of DNA-RFLPs at these gene loci revealed by EcoRI and AccII respectively. Here we report results from a study comparing lung cancer cases (n = 31) with chronic obstructive pulmonary disease controls (n = 49). No association was found between these RFLPs and disease status. Previous observations that the frequencies of these RFLPs varied by race were confirmed. The p53 arginine allele was found to be more common in Caucasians (0.71) than African-Americans (0.50). The EcoRI restriction site present allele in L-myc was more frequent in African-Americans (0.71) than Caucasians (0.49). Thus, the allelic frequency for L-myc was similar in African-Americans to that reported for Japanese, and the allelic frequency for p53 was similar in Caucasians to that reported for Japanese.

  15. Intensity-modulated radiation therapy for pancreatic and prostate cancer using pulsed low-dose rate delivery techniques.

    PubMed

    Li, Jie; Lang, Jinyi; Wang, Pei; Kang, Shengwei; Lin, Mu-Han; Chen, Xiaoming; Chen, Fu; Guo, Ming; Chen, Lili; Ma, Chang-Ming Charlie

    2014-01-01

    Reirradiation of patients who were previously treated with radiotherapy is vastly challenging. Pulsed low-dose rate (PLDR) external beam radiotherapy has the potential to reduce normal tissue toxicities while providing significant tumor control for recurrent cancers. This work investigates treatment planning techniques for intensity-modulated radiation therapy (IMRT)-based PLDR treatment of various sites, including cases with pancreatic and prostate cancer. A total of 20 patients with clinical recurrence were selected for this study, including 10 cases with pancreatic cancer and 10 with prostate cancer. Large variations in the target volume were included to test the ability of IMRT using the existing treatment planning system and optimization algorithm to deliver uniform doses in individual gantry angles/fields for PLDR treatments. Treatment plans were generated with 10 gantry angles using the step-and-shoot IMRT delivery technique, which can be delivered in 3-minute intervals to achieve an effective low dose rate of 6.7cGy/min. Instead of dose constraints on critical structures, ring structures were mainly used in PLDR-IMRT optimization. In this study, the PLDR-IMRT plans were compared with the PLDR-3-dimensional conformal radiation therapy (3DCRT) plans and the PLDR-RapidArc plans. For the 10 cases with pancreatic cancer that were investigated, the mean planning target volume (PTV) dose for each gantry angle in the PLDR-IMRT plans ranged from 17.6 to 22.4cGy. The maximum doses ranged between 22.9 and 34.8cGy. The minimum doses ranged from 8.2 to 17.5cGy. For the 10 cases with prostate cancer that were investigated, the mean PTV doses for individual gantry angles ranged from 18.8 to 22.6cGy. The maximum doses per gantry angle were between 24.0 and 34.7cGy. The minimum doses per gantry angle ranged from 4.4 to 17.4cGy. A significant reduction in the organ at risk (OAR) dose was observed with the PLDR-IMRT plan when compared with that using the PLDR-3DCRT plan. The

  16. Intensity-modulated radiation therapy for pancreatic and prostate cancer using pulsed low–dose rate delivery techniques

    SciTech Connect

    Li, Jie; Lang, Jinyi; Wang, Pei; Kang, Shengwei; Lin, Mu-han; Chen, Xiaoming; Chen, Fu; Guo, Ming; Chen, Lili; Ma, Chang-Ming Charlie

    2014-01-01

    Reirradiation of patients who were previously treated with radiotherapy is vastly challenging. Pulsed low–dose rate (PLDR) external beam radiotherapy has the potential to reduce normal tissue toxicities while providing significant tumor control for recurrent cancers. This work investigates treatment planning techniques for intensity-modulated radiation therapy (IMRT)-based PLDR treatment of various sites, including cases with pancreatic and prostate cancer. A total of 20 patients with clinical recurrence were selected for this study, including 10 cases with pancreatic cancer and 10 with prostate cancer. Large variations in the target volume were included to test the ability of IMRT using the existing treatment planning system and optimization algorithm to deliver uniform doses in individual gantry angles/fields for PLDR treatments. Treatment plans were generated with 10 gantry angles using the step-and-shoot IMRT delivery technique, which can be delivered in 3-minute intervals to achieve an effective low dose rate of 6.7 cGy/min. Instead of dose constraints on critical structures, ring structures were mainly used in PLDR-IMRT optimization. In this study, the PLDR-IMRT plans were compared with the PLDR-3-dimensional conformal radiation therapy (3DCRT) plans and the PLDR-RapidArc plans. For the 10 cases with pancreatic cancer that were investigated, the mean planning target volume (PTV) dose for each gantry angle in the PLDR-IMRT plans ranged from 17.6 to 22.4 cGy. The maximum doses ranged between 22.9 and 34.8 cGy. The minimum doses ranged from 8.2 to 17.5 cGy. For the 10 cases with prostate cancer that were investigated, the mean PTV doses for individual gantry angles ranged from 18.8 to 22.6 cGy. The maximum doses per gantry angle were between 24.0 and 34.7 cGy. The minimum doses per gantry angle ranged from 4.4 to 17.4 cGy. A significant reduction in the organ at risk (OAR) dose was observed with the PLDR-IMRT plan when compared with that using the PLDR-3DCRT

  17. Effect of bacterial ice nuclei on the frequency and intensity of lightning activity inferred by the BRAMS model

    NASA Astrophysics Data System (ADS)

    Gonçalves, F. L. T.; Martins, J. A.; Albrecht, R. I.; Morales, C. A.; Silva Dias, M. A.; Morris, C. E.

    2012-07-01

    Many studies from the last decades have shown that airborne microorganisms can be intrinsically linked to atmospheric processes. Certain bacteria may constitute the most active ice nuclei found in the atmosphere and might have some influence on the formation of ice crystals in clouds. This study deals with the ice nucleation activity of Pseudomonas syringae inside of thunderstorms through numerical simulations using BRAMS (Brazilian Regional Atmospheric Model System). The numerical simulations were developed in order to investigate the effect on the total amount of rainwater as a function of ice nuclei (IN) P. syringae concentrations with different scenarios (classified as S2 to S4 scenarios) corresponding to a maximum of 102 to 104 IN bacteria per liter of cloud water plus the BRAMS default (classified as S5 scenario). Additionally, two other scenarios were included without any IN (S1) and the sum of RAMS default and S4 scenario (classified as S6). The chosen radiosonde data is for 3 March 2003, typical summertime in São Paulo City which presents a strong convective cell. The objective of the simulations was to analyze the effect of the IN concentrations on the BRAMS modeled cloud properties and precipitation. The simulated electrification of the cloud permitted analysis of the total flashes estimated from precipitable and non-precipitable ice mass fluxes in two different lightning frequencies. Among all scenarios, only S4 and S6 presented a tendency to decrease the total cloud water, and all bacteria scenarios presented a tendency to decrease the total amount of rain (-8%), corroborating other reports in the literature. All bacteria scenarios also present higher precipitable ice concentrations compared to S5 scenario, the RAMS default. The main results present the total flash number per simulation as well. From the results, the total flash numbers, from both lightning frequencies, in S4 and S6 scenarios, are from 3.1 to 3.7 higher than the BRAMS default. Even

  18. Effect of intense THz pulses on expression of genes associated with skin cancer and inflammatory skin conditions

    NASA Astrophysics Data System (ADS)

    Titova, Lyubov V.; Ayesheshim, Ayesheshim K.; Purschke, David; Golubov, Andrey; Rodriguez-Juarez, Rocio; Woycicki, Rafal; Hegmann, Frank A.; Kovalchuk, Olga

    2014-03-01

    The growing experimental evidence suggests that broadband, picosecond-duration THz pulses may influence biological systems and functions. While the mechanisms by which THz pulse-induced biological effects are not yet known, experiments using in vitro cell cultures, tissue models, as well as recent in vivo studies have demonstrated that THz pulses can elicit cellular and molecular changes in exposed cells and tissues in the absence of thermal effects. Recently, we demonstrated that intense, picosecond THz pulses induce phosphorylation of H2AX, indicative of DNA damage, and at the same time activate DNA damage response in human skin tissues. We also find that intense THz pulses have a profound impact on global gene expression in human skin. Many of the affected genes have important functions in epidermal differentiation and have been implicated in skin cancer and inflammatory skin conditions. The observed THzinduced changes in expression of these genes are in many cases opposite to disease-related changes, suggesting possible therapeutic applications of intense THz pulses.

  19. High intensity focused ultrasound (HIFU) for treatment of T1/T2 prostate cancer

    NASA Astrophysics Data System (ADS)

    Sanghvi, N.; Gardner, T.; Koch, M.

    2003-04-01

    This FDA approved phase I/II clinical trial is to evaluate the safety and efficacy of the Sonablate device (Focus Surgery, Inc.) for the treatment of organ confined prostate cancer. 20 patients with biopsy proven prostate cancer, Gleason <=7 and PSA <=10 were treated under general anesthesia. Outcome data included serum PSA collected at day 3, 14, 30, 90, 180, PSA nadir (mean/median), and biopsy results at 6 months. Quality of life was assessed using the International Prostate Symptom Score, International Impotence and Erectile Function score, and the SF-36 health survey. The mean patient age is 62.0, Gleason score of 6.18, PSA of 5.2, and prostate size 26.0 gm. Mean PSA results were 5.62, 44, 20, 1.68, 0.87, and 0.44 ng/ml at screening, 48-72 hours, 14 days, 30 days, 90 days and 180 days, respectively. There was one patient (9%) with a positive TRUS biopsy at 6 months, which resulted in a retreatment. There were no rectal injuries. Average pre-treatment IPSS, IIEF, and SF-36 scores were 9.55, 16.1, and 103.5. At the 30 day follow-up, they were 18.3, 3, and 97.4, respectively. HIFU is a minimally invasive modality that achieves complete prostatic ablation and is efficacious in the treatment of low-stage prostate cancer.

  20. Effect Modification of the Association of Cumulative Exposure and Cancer Risk by Intensity of Exposure and Time Since Exposure Cessation: A Flexible Method Applied to Cigarette Smoking and Lung Cancer in the SYNERGY Study

    PubMed Central

    Vlaanderen, Jelle; Portengen, Lützen; Schüz, Joachim; Olsson, Ann; Pesch, Beate; Kendzia, Benjamin; Stücker, Isabelle; Guida, Florence; Brüske, Irene; Wichmann, Heinz-Erich; Consonni, Dario; Landi, Maria Teresa; Caporaso, Neil; Siemiatycki, Jack; Merletti, Franco; Mirabelli, Dario; Richiardi, Lorenzo; Gustavsson, Per; Plato, Nils; Jöckel, Karl-Heinz; Ahrens, Wolfgang; Pohlabeln, Hermann; Tardón, Adonina; Zaridze, David; Field, John K.; 't Mannetje, Andrea; Pearce, Neil; McLaughlin, John; Demers, Paul; Szeszenia-Dabrowska, Neonila; Lissowska, Jolanta; Rudnai, Peter; Fabianova, Eleonora; Stanescu Dumitru, Rodica; Bencko, Vladimir; Foretova, Lenka; Janout, Vladimir; Boffetta, Paolo; Forastiere, Francesco; Bueno-de-Mesquita, Bas; Peters, Susan; Brüning, Thomas; Kromhout, Hans; Straif, Kurt; Vermeulen, Roel

    2014-01-01

    The indiscriminate use of the cumulative exposure metric (the product of intensity and duration of exposure) might bias reported associations between exposure to hazardous agents and cancer risk. To assess the independent effects of duration and intensity of exposure on cancer risk, we explored effect modification of the association of cumulative exposure and cancer risk by intensity of exposure. We applied a flexible excess odds ratio model that is linear in cumulative exposure but potentially nonlinear in intensity of exposure to 15 case-control studies of cigarette smoking and lung cancer (1985–2009). Our model accommodated modification of the excess odds ratio per pack-year of cigarette smoking by time since smoking cessation among former smokers. We observed negative effect modification of the association of pack-years of cigarette smoking and lung cancer by intensity of cigarette smoke for persons who smoked more than 20–30 cigarettes per day. Patterns of effect modification were similar across individual studies and across major lung cancer subtypes. We observed strong negative effect modification by time since smoking cessation. Application of our method in this example of cigarette smoking and lung cancer demonstrated that reducing a complex exposure history to a metric such as cumulative exposure is too restrictive. PMID:24355332

  1. Effect modification of the association of cumulative exposure and cancer risk by intensity of exposure and time since exposure cessation: a flexible method applied to cigarette smoking and lung cancer in the SYNERGY Study.

    PubMed

    Vlaanderen, Jelle; Portengen, Lützen; Schüz, Joachim; Olsson, Ann; Pesch, Beate; Kendzia, Benjamin; Stücker, Isabelle; Guida, Florence; Brüske, Irene; Wichmann, Heinz-Erich; Consonni, Dario; Landi, Maria Teresa; Caporaso, Neil; Siemiatycki, Jack; Merletti, Franco; Mirabelli, Dario; Richiardi, Lorenzo; Gustavsson, Per; Plato, Nils; Jöckel, Karl-Heinz; Ahrens, Wolfgang; Pohlabeln, Hermann; Tardón, Adonina; Zaridze, David; Field, John K; 't Mannetje, Andrea; Pearce, Neil; McLaughlin, John; Demers, Paul; Szeszenia-Dabrowska, Neonila; Lissowska, Jolanta; Rudnai, Peter; Fabianova, Eleonora; Stanescu Dumitru, Rodica; Bencko, Vladimir; Foretova, Lenka; Janout, Vladimir; Boffetta, Paolo; Forastiere, Francesco; Bueno-de-Mesquita, Bas; Peters, Susan; Brüning, Thomas; Kromhout, Hans; Straif, Kurt; Vermeulen, Roel

    2014-02-01

    The indiscriminate use of the cumulative exposure metric (the product of intensity and duration of exposure) might bias reported associations between exposure to hazardous agents and cancer risk. To assess the independent effects of duration and intensity of exposure on cancer risk, we explored effect modification of the association of cumulative exposure and cancer risk by intensity of exposure. We applied a flexible excess odds ratio model that is linear in cumulative exposure but potentially nonlinear in intensity of exposure to 15 case-control studies of cigarette smoking and lung cancer (1985-2009). Our model accommodated modification of the excess odds ratio per pack-year of cigarette smoking by time since smoking cessation among former smokers. We observed negative effect modification of the association of pack-years of cigarette smoking and lung cancer by intensity of cigarette smoke for persons who smoked more than 20-30 cigarettes per day. Patterns of effect modification were similar across individual studies and across major lung cancer subtypes. We observed strong negative effect modification by time since smoking cessation. Application of our method in this example of cigarette smoking and lung cancer demonstrated that reducing a complex exposure history to a metric such as cumulative exposure is too restrictive.

  2. Time dependent Doppler shifts in high-order harmonic generation in intense laser interactions with solid density plasma and frequency chirped pulses

    SciTech Connect

    Welch, E. C.; Zhang, P.; He, Z.-H.; Dollar, F.; Krushelnick, K.; Thomas, A. G. R.

    2015-05-15

    High order harmonic generation from solid targets is a compelling route to generating intense attosecond or even zeptosecond pulses. However, the effects of ion motion on the generation of harmonics have only recently started to be considered. Here, we study the effects of ion motion in harmonics production at ultrahigh laser intensities interacting with solid density plasma. Using particle-in-cell simulations, we find that there is an optimum density for harmonic production that depends on laser intensity, which scales linearly with a{sub 0} with no ion motion but with a reduced scaling if ion motion is included. We derive a scaling for this optimum density with ion motion and also find that the background ion motion induces Doppler red-shifts in the harmonic structures of the reflected pulse. The temporal structure of the Doppler shifts is correlated to the envelope of the incident laser pulse. We demonstrate that by introducing a frequency chirp in the incident pulse we are able to eliminate these Doppler shifts almost completely.

  3. Australasian Gastrointestinal Trials Group (AGITG) Contouring Atlas and Planning Guidelines for Intensity-Modulated Radiotherapy in Anal Cancer

    SciTech Connect

    Ng, Michael; Leong, Trevor; Chander, Sarat; Chu, Julie; Kneebone, Andrew; Carroll, Susan; Wiltshire, Kirsty; Ngan, Samuel; Kachnic, Lisa

    2012-08-01

    Purpose: To develop a high-resolution target volume atlas with intensity-modulated radiotherapy (IMRT) planning guidelines for the conformal treatment of anal cancer. Methods and Materials: A draft contouring atlas and planning guidelines for anal cancer IMRT were prepared at the Australasian Gastrointestinal Trials Group (AGITG) annual meeting in September 2010. An expert panel of radiation oncologists contoured an anal cancer case to generate discussion on recommendations regarding target definition for gross disease, elective nodal volumes, and organs at risk (OARs). Clinical target volume (CTV) and planning target volume (PTV) margins, dose fractionation, and other IMRT-specific issues were also addressed. A steering committee produced the final consensus guidelines. Results: Detailed contouring and planning guidelines and a high-resolution atlas are provided. Gross tumor and elective target volumes are described and pictorially depicted. All elective regions should be routinely contoured for all disease stages, with the possible exception of the inguinal and high pelvic nodes for select, early-stage T1N0. A 20-mm CTV margin for the primary, 10- to 20-mm CTV margin for involved nodes and a 7-mm CTV margin for the elective pelvic nodal groups are recommended, while respecting anatomical boundaries. A 5- to 10-mm PTV margin is suggested. When using a simultaneous integrated boost technique, a dose of 54 Gy in 30 fractions to gross disease and 45 Gy to elective nodes with chemotherapy is appropriate. Guidelines are provided for OAR delineation. Conclusion: These consensus planning guidelines and high-resolution atlas complement the existing Radiation Therapy Oncology Group (RTOG) elective nodal ano-rectal atlas and provide additional anatomic, clinical, and technical instructions to guide radiation oncologists in the planning and delivery of IMRT for anal cancer.

  4. Low-intensity ultrasound enhances the anticancer activity of cetuximab in human head and neck cancer cells.

    PubMed

    Masui, Takashi; Ota, Ichiro; Kanno, Masatoshi; Yane, Katsunari; Hosoi, Hiroshi

    2013-01-01

    The potential clinical use of ultrasound in inducing cell apoptosis and enhancing the effects of anticancer drugs in the treatment of cancers has previously been investigated. In this study, the combined effects of low-intensity ultrasound (LIU) and cetuximab, an anti-epidermal growth factor receptor (EGFR) antibody, on cell killing and induction of apoptosis in HSC-3 and HSC-4 head and neck cancer cells, and its mechanisms were investigated. Experiments were divided into 4 groups: non-treated (CNTRL), cetuximab-treated (CETU), ultrasound-treated (UST) and the combination of cetuximab and US-treated (COMB). Cell viability was assessed by trypan blue staining assay and induction of apoptosis was detected by fluorescein isothiocyanate (FITC)-Annexin V and propidium iodide (PI) staining assay at 24 h after cetuximab and/or US treatment. To elucidate the effect of cetuximab and US on EGFR signaling and apoptosis in head and neck cancer cells after the treatments, the expression of EGFR, phospho-EGFR, and the activation of caspase-3 were evaluated with western blotting. More cell killing features were evident in the COMB group in HSC-3 and HSC-4 cells compared with the other groups. No differences in EGFR expression among the CETU, UST and COMB groups was observed, while the expression of phospho-EGFR in the CETU group was downregulated compared with that in the CNTRL group. Phospho-EGFR expression was much more downregulated in the COMB group compared with that in the other groups. In addition, the activation of caspase-3 in the UST group was upregulated compared with that in the CNTRL group. Caspase-3 activation was much more upregulated in the COMB group than that in the other groups. These data indicated that LIU was able to enhance the anticancer effect of cetuximab in HSC-3 and HSC-4 head and neck cancer cells.

  5. Cervical Lymph Node Metastases From Unknown Primary Cancer: A Single-Institution Experience With Intensity-Modulated Radiotherapy

    SciTech Connect

    Villeneuve, Hugo; Despres, Philippe; Fortin, Bernard; Filion, Edith; Donath, David; Soulieres, Denis; Guertin, Louis; Ayad, Tarek; Christopoulos, Apostolos; Nguyen-Tan, Phuc Felix

    2012-04-01

    Purpose: To determine the effectiveness and rate of complications of intensity-modulated radiotherapy (IMRT) in the treatment of cervical lymph node metastases from unknown primary cancer. Methods and Materials: Between February 2005 and November 2008, 25 patients with an unknown primary cancer underwent IMRT, with a median radiation dose of 70 Gy. The bilateral neck and ipsilateral putative pharyngeal mucosa were included in the target volume. All patients had squamous cell carcinoma, except for 1 patient who had adenosquamous differentiation. They were all treated with curative intent. Of the 25 included patients, 20 were men and 5 were women, with a median age of 54 years. Of these patients, 3 had Stage III, 18 had Stage IVa, and 4 had Stage IVb. Of the 25 patients, 18 (72%) received platinum-based chemotherapy in a combined-modality setting. Neck dissection was reserved for residual disease after definitive IMRT. Overall survival, disease-free survival, and locoregional control were calculated using the Kaplan-Meier method. Results: With a median follow-up of 38 months, the overall survival, disease-free survival, and locoregional control rates were all 100% at 3 years. No occurrence of primary cancer was observed during the follow-up period. The reported rates of xerostomia reduced with the interval from the completion of treatment. Nine patients (36%) reported Grade 2 or greater xerostomia at 6 months, and only 2 (8%) of them reported the same grade of salivary function toxicity after 24 months of follow-up. Conclusion: In our institution, IMRT for unknown primary cancer has provided good overall and disease-free survival in all the patients with an acceptable rate of complications. IMRT allowed us to address the bilateral neck and ipsilateral putative pharyngeal mucosa with minimal late salivary function toxicity. The use of concurrent chemotherapy and IMRT for more advanced disease led to good clinical results with reasonable toxicities.

  6. Rainfall and runoff Intensity-Duration-Frequency Curves for Washington State considering the change and uncertainty of observed and anticipated extreme rainfall and snow events

    NASA Astrophysics Data System (ADS)

    Demissie, Y. K.; Mortuza, M. R.; Li, H. Y.

    2015-12-01

    The observed and anticipated increasing trends in extreme storm magnitude and frequency, as well as the associated flooding risk in the Pacific Northwest highlighted the need for revising and updating the local intensity-duration-frequency (IDF) curves, which are commonly used for designing critical water infrastructure. In Washington State, much of the drainage system installed in the last several decades uses IDF curves that are outdated by as much as half a century, making the system inadequate and vulnerable for flooding as seen more frequently in recent years. In this study, we have developed new and forward looking rainfall and runoff IDF curves for each county in Washington State using recently observed and projected precipitation data. Regional frequency analysis coupled with Bayesian uncertainty quantification and model averaging methods were used to developed and update the rainfall IDF curves, which were then used in watershed and snow models to develop the runoff IDF curves that explicitly account for effects of snow and drainage characteristic into the IDF curves and related designs. The resulted rainfall and runoff IDF curves provide more reliable, forward looking, and spatially resolved characteristics of storm events that can assist local decision makers and engineers to thoroughly review and/or update the current design standards for urban and rural storm water management infrastructure in order to reduce the potential ramifications of increasing severe storms and resulting floods on existing and planned storm drainage and flood management systems in the state.

  7. Reduction of Edge Localized Mode Intensity on DIII-D by On-demand triggering with High Frequency Pellet Injection and Implications for ITER

    SciTech Connect

    Baylor, Larry R; Commaux, Nicolas JC; Jernigan, T. C.; Meitner, Steven J; Combs, Stephen Kirk; Isler, Ralph C; Unterberg, Ezekial A; Brooks, N. H.; Evans, T. E.; Leonard, A. W.; Osborne, T. H.; Parks, P. B.; Snyder, P. B.; Strait, E. J.; Fenstermacher, M. E.; Lasnier, C. J.; Moyer, R. A.; Loarte, A.; Huijsmans, G. T.A.; Futantani, S.

    2013-01-01

    The injection of small deuterium pellets at high repetition rates up to 12 the natural edge localized mode (ELM) frequency has been used to trigger high-frequency ELMs in otherwise low natural ELM frequency H-mode deuterium discharges in the DIII-D tokamak [J. L. Luxon and L. G. Davis, Fusion Technol. 8, 441 (1985)]. The resulting pellet-triggered ELMs result in up to 12 lower energy and particle fluxes to the divertor than the natural ELMs. The plasma global energy confinement and density are not strongly affected by the pellet perturbations. The plasma core impurity density is strongly reduced with the application of the pellets. These experiments were performed with pellets injected from the low field side pellet in plasmas designed to match the ITER baseline configuration in shape and normalized operation with input heating power just above the H-mode power threshold. Nonlinear MHD simulations of the injected pellets show that destabilization of ballooning modes by a local pressure perturbation is responsible for the pellet ELM triggering. This strongly reduced ELM intensity shows promise for exploitation in ITER to control ELM size while maintaining high plasma purity and performance.

  8. Reduction of edge localized mode intensity on DIII-D by on-demand triggering with high frequency pellet injection and implications for ITER

    SciTech Connect

    Baylor, L. R.; Commaux, N.; Jernigan, T. C.; Meitner, S. J.; Combs, S. K.; Isler, R. C.; Unterberg, E. A.; Brooks, N. H.; Evans, T. E.; Leonard, A. W.; Osborne, T. H.; Parks, P. B.; Snyder, P. B.; Strait, E. J.; Fenstermacher, M. E.; Lasnier, C. J.; Moyer, R. A.; Loarte, A.; Huijsmans, G. T. A.; Futatani, S.

    2013-08-15

    The injection of small deuterium pellets at high repetition rates up to 12× the natural edge localized mode (ELM) frequency has been used to trigger high-frequency ELMs in otherwise low natural ELM frequency H-mode deuterium discharges in the DIII-D tokamak [J. L. Luxon and L. G. Davis, Fusion Technol. 8, 441 (1985)]. The resulting pellet-triggered ELMs result in up to 12× lower energy and particle fluxes to the divertor than the natural ELMs. The plasma global energy confinement and density are not strongly affected by the pellet perturbations. The plasma core impurity density is strongly reduced with the application of the pellets. These experiments were performed with pellets injected from the low field side pellet in plasmas designed to match the ITER baseline configuration in shape and normalized β operation with input heating power just above the H-mode power threshold. Nonlinear MHD simulations of the injected pellets show that destabilization of ballooning modes by a local pressure perturbation is responsible for the pellet ELM triggering. This strongly reduced ELM intensity shows promise for exploitation in ITER to control ELM size while maintaining high plasma purity and performance.

  9. High frequency occurrence of 1-OPRD variant of PRNP gene in gastric cancer cell lines and Chinese population with gastric cancer.

    PubMed

    Liang, J; Wang, J B; Pan, Y L; Wang, J; Liu, L L; Guo, X Y; Sun, L; Lin, T; Han, S; Xie, H H; Yin, F; Guo, X G; Fan, D

    2006-11-01

    The prion protein gene PRNP encodes PrPc and PrPsc, causing a number of neurological disorders. Approximately 10-15% of human prion disease is inherited and more than 20 pathogenic mutations have been found. Most of the genetic alterations are point mutations, with the exception of genetic insertions of one to nine extra octapeptide repeats occurring in the important octapeptide-coding region. Our previous work showed that PrPc was overexpressed in gastric cancer. We wondered whether mutations of PrPc existed in human gastric cancer. DNA sequencing and gel electrophoresis were used to determine the possible mutation of PrPc in patients and cell lines of gastric cancer. We found that 1-OPRD (one octapeptide-repeat deletion) homozygosity or heterozygosity exists in several gastric cancer cell lines, e.g. MKN28 and KatoIII are homozygous for 1-OPRD, and SGC7901 and BGC-823 are heterozygous for 1-OPRD. The mutation frequency in tissues of gastric cancer cases is significantly higher than that in the common population (p<0.05). All positive cases in gastric cancer were found to be heterozygous for 1-OPRD. Further study of the variant may be helpful in understanding the mechanisms of occurrence and development of clinical gastric carcinoma as well as the biology of the mysterious gene PRNP. PMID:16914329

  10. Robotic high-intensity focused ultrasound (rHIFU) for the prostate cancer treatment

    NASA Astrophysics Data System (ADS)

    Solovov, Vyacheslav; Shaplygin, Leonid; Vozdvizhenskiy, Mikhail

    2012-11-01

    Introduction & Objectives: rHIFU shows a successful treatment for localized prostate cancer (PC). Here we explored the effectiveness of the rHIFU treatment for the prostate cancer, hormone-resistant prostate cancer (HRPC) and failure after external beam radiotherapy (EBRT) and radical prostatectomy (RPE). Materials & Methods: 748 patients were treated in our center between Sep 2007 - February 2012: 137 - hormone-resistance (median time before hormone-resistance 25 months), 286 - received neoadjuvant hormone therapy 6 months, 293 - no treatment before HIFU, 32 - after the EBRT failure. 667 patients underwent TURP+rHIFU, 81 only rHIFU (volume prostate <40cc). Mean follow-up is 38 months (range 3-52). All patients were divided into 3 groups: low risk progression (Gleason <7, stage T1-2N0M0, PSA<20, n= 465), high risk progression - (Gleason ≤9, stage T2-3N0M0, PSA <60, n= 251), after EBRT and RPE failure (n= 39). The mean age of the whole group of patients were 70 (52-89) years, mean prostate volume - 39 (5,5-108) cc. Results: Median PSA level 12 months after rHIFU treatment were 0,04 (0-2,24) ng/ml - low risk group, for high risk group - 0,5 (0-48,4) ng/ml, with failure after EBRT and RPE- 0,5 (0-3,2) ng/ml; 36 months after rHIFU treatment were 0,5 (0,02-3,6) ng/ml - low risk group, for high risk group - 3,2 (0-21,38) ng/ml, with failure after EBRT and RPE - 1,7 (0-9,8) ng/ml. Patients with low risk had 4,5% of progression, with high risk PC - 25%, with failure after EBRT and RPE - 19,6%. Kaplan-Meir analyses of the total group indicated that the risk of progression after 1 year follow-up was 10%, the risk of progression was 23% after 4 years of follow-up. Complications: incontinence I - 17,5%, incontinence II - 7,7%, stricture - 18,2%, fistula - 0,3 %. Conclusions: Our experience shows that rHIFU ablation is safe, minimally invasive, effective treatment with moderate side effects for the PC, hormone-resistant prostate cancer, rHIFU also may be used as a salvage

  11. Transrectal high-intensity focused ultrasound ablation of prostate cancer: effective treatment requiring accurate imaging.

    PubMed

    Rouvière, Olivier; Souchon, Rémi; Salomir, Rarès; Gelet, Albert; Chapelon, Jean-Yves; Lyonnet, Denis

    2007-09-01

    Transrectal HIFU ablation has become a reasonable option for the treatment of localized prostate cancer in non-surgical patients, with 5-year disease-free survival similar to that of radiation therapy. It is also a promising salvage therapy of local recurrence after radiation therapy. These favourable results are partly due to recent improvements in prostate cancer imaging. However, further improvements are needed in patient selection, pre-operative localization of the tumor foci, assessment of the volume treated and early detection of recurrence. A better knowledge of the factors influencing the HIFU-induced tissue destruction and a better pre-operative assessment of them by imaging techniques should improve treatment outcome. Whereas prostate HIFU ablation is currently performed under transrectal ultrasound guidance, MR guidance with real-time operative monitoring of temperature will be available in the near future. If this technique will give better targeting and more uniform tissue destruction, its cost-effectiveness will have to be carefully evaluated. Finally, a recently reported synergistic effect between HIFU ablation and chemotherapy opens possibilities for treatment in high-risk or clinically advanced tumors.

  12. The association between frequencies of mitomycin C-induced sister chromatid exchange and cancer risk in arseniasis.

    PubMed

    Liou, Saou-Hsing; Chen, Yeong-Hwang; Loh, Ching-Hui; Yang, Tsan; Wu, Trong-Neng; Chen, Chien-Jen; Hsieh, Ling-Ling

    2002-03-28

    In order to examine whether biomarkers of cytogenetic damage and susceptibility, such as spontaneous and mitomycin C-induced sister chromatid exchange (SCE) can predict cancer development, a nested case-control study was performed in a blackfoot endemic area with known high cancer risk. A cohort of 686 residents was recruited from three villages in the arseniasis area. Personal characteristics were collected and venous blood was drawn for lymphocyte culture and stored in a refrigerator. The vital status and cancer development was followed using the National Death Registry, Cancer Registry, and Blackfoot Disease Registry. The follow up period was from August 1991 to July 1997. During this 6-year-period, 55 residents developed various types of cancer. Blood culture samples from 23 of these subjects were unsuitable for spontaneous SCE experiments and 45 of these subjects were unsuitable for mitomycin C-induced SCE experiments due to improper storage. Finally, a total of 32 cancer cases had cytogenetic samples that could be analyzed. About 32 control subjects were selected from those who did not develop cancer in the study period and these subjects were matched to cases by sex, age, smoking habits, and residential area. The results showed that there was no significant difference in the frequencies of spontaneous and mitomycin C-induced SCE between the case and control groups. There was also no significant difference in the net difference of spontaneous and mitomycin C-induced SCE between the case and control groups. These results suggest that SCEs, either spontaneous or mitomycin C-induced, might not be good markers to predict cancer risk.

  13. Intensity-modulated radiation therapy for head and neck cancer: emphasis on the selection and delineation of the targets.

    PubMed

    Eisbruch, Avraham; Foote, Robert L; O'Sullivan, Brian; Beitler, Jonathan J; Vikram, Bhadrasain

    2002-07-01

    The head and neck contain many critical, noninvolved structures in close vicinity to the targets. The tightly conformal doses produced by intensity-modulated radiation therapy (IMRT), and the lack of internal organ motion in the head and neck, provide the potential for organ sparing and improved tumor irradiation. Many studies of treatment planning for head and neck cancer have demonstrated the dosimetric superiority of IMRT over conventional techniques in these respects. The initial results of clinical studies demonstrate reduced xerostomia. They suggest an improvement in tumor control, which needs to be verified in larger studies and longer follow-up. Critical issues for successful outcome of head and neck IMRT are accurate selection of the neck lymph nodes that require adjuvant treatment, and accurate delineation on the planning computed tomography (CT) of the lymph-node bearing areas and subclinical disease adjoining the gross tumor. This review emphasizes these topics and provides some guidelines. PMID:12118389

  14. Evaluation of Dose Distribution in Intensity Modulated Radiosurgery for Lung Cancer under Condition of Respiratory Motion

    PubMed Central

    Yoon, Mee Sun; Jeong, Jae-Uk; Nam, Taek-Keun; Ahn, Sung-Ja; Chung, Woong-Ki; Song, Ju-Young

    2016-01-01

    The dose of a real tumor target volume and surrounding organs at risk (OARs) under the effect of respiratory motion was calculated for a lung tumor plan, based on the target volume covering the whole tumor motion range for intensity modulated radiosurgery (IMRS). Two types of IMRS plans based on simulated respiratory motion were designed using humanoid and dynamic phantoms. Delivery quality assurance (DQA) was performed using ArcCHECK and MapCHECK2 for several moving conditions of the tumor and the real dose inside the humanoid phantom was evaluated using the 3DVH program. This evaluated dose in the tumor target and OAR using the 3DVH program was higher than the calculated dose in the plan, and a greater difference was seen for the RapidArc treatment than for the standard intensity modulated radiation therapy (IMRT) with fixed gantry angle beams. The results of this study show that for IMRS plans based on target volume, including the whole tumor motion range, tighter constraints of the OAR should be considered in the optimization process. The method devised in this study can be applied effectively to analyze the dose distribution in the real volume of tumor target and OARs in IMRT plans targeting the whole tumor motion range. PMID:27648949

  15. Evaluation of Dose Distribution in Intensity Modulated Radiosurgery for Lung Cancer under Condition of Respiratory Motion.

    PubMed

    Yoon, Mee Sun; Jeong, Jae-Uk; Nam, Taek-Keun; Ahn, Sung-Ja; Chung, Woong-Ki; Song, Ju-Young

    2016-01-01

    The dose of a real tumor target volume and surrounding organs at risk (OARs) under the effect of respiratory motion was calculated for a lung tumor plan, based on the target volume covering the whole tumor motion range for intensity modulated radiosurgery (IMRS). Two types of IMRS plans based on simulated respiratory motion were designed using humanoid and dynamic phantoms. Delivery quality assurance (DQA) was performed using ArcCHECK and MapCHECK2 for several moving conditions of the tumor and the real dose inside the humanoid phantom was evaluated using the 3DVH program. This evaluated dose in the tumor target and OAR using the 3DVH program was higher than the calculated dose in the plan, and a greater difference was seen for the RapidArc treatment than for the standard intensity modulated radiation therapy (IMRT) with fixed gantry angle beams. The results of this study show that for IMRS plans based on target volume, including the whole tumor motion range, tighter constraints of the OAR should be considered in the optimization process. The method devised in this study can be applied effectively to analyze the dose distribution in the real volume of tumor target and OARs in IMRT plans targeting the whole tumor motion range. PMID:27648949

  16. Positron Emission Tomography-Guided, Focal-Dose Escalation Using Intensity-Modulated Radiotherapy for Head and Neck Cancer

    SciTech Connect

    Madani, Indira . E-mail: indira@krtkg1.ugent.be; Duthoy, Wim; Derie, Cristina R.N.; De Gersem, Werner Ir.; Boterberg, Tom; Saerens, Micky; Jacobs, Filip Ir.; Gregoire, Vincent; Lonneux, Max; Vakaet, Luc; Vanderstraeten, Barbara; Bauters, Wouter; Bonte, Katrien; Thierens, Hubert; Neve, Wilfried de

    2007-05-01

    Purpose: To assess the feasibility of intensity-modulated radiotherapy (IMRT) using positron emission tomography (PET)-guided dose escalation, and to determine the maximum tolerated dose in head and neck cancer. Methods and Materials: A Phase I clinical trial was designed to escalate the dose limited to the [{sup 18}-F]fluoro-2-deoxy-D-glucose positron emission tomography ({sup 18}F-FDG-PET)-delineated subvolume within the gross tumor volume. Positron emission tomography scanning was performed in the treatment position. Intensity-modulated radiotherapy with an upfront simultaneously integrated boost was employed. Two dose levels were planned: 25 Gy (level I) and 30 Gy (level II), delivered in 10 fractions. Standard IMRT was applied for the remaining 22 fractions of 2.16 Gy. Results: Between 2003 and 2005, 41 patients were enrolled, with 23 at dose level I, and 18 at dose level II; 39 patients completed the planned therapy. The median follow-up for surviving patients was 14 months. Two cases of dose-limiting toxicity occurred at dose level I (Grade 4 dermitis and Grade 4 dysphagia). One treatment-related death at dose level II halted the study. Complete response was observed in 18 of 21 (86%) and 13 of 16 (81%) evaluated patients at dose levels I and II (p < 0.7), respectively, with actuarial 1-year local control at 85% and 87% (p n.s.), and 1-year overall survival at 82% and 54% (p = 0.06), at dose levels I and II, respectively. In 4 of 9 patients, the site of relapse was in the boosted {sup 18}F-FDG-PET-delineated region. Conclusions: For head and neck cancer, PET-guided dose escalation appears to be well-tolerated. The maximum tolerated dose was not reached at the investigated dose levels.

  17. Dynamics of a one-dimensional model and a three-dimensional hydrogen atom in an intense high-frequency short-pulse laser

    SciTech Connect

    Tang, X. ); Basile, S. di Fisica Teorica dell'Universita, Casello Postale 50, 98166 Sant'Agata di Messina, Messina, Italy )

    1991-08-01

    We present nonperturbative calculations of ionizing and trapping probabilities for a one-dimensional model and a three-dimensional hydrogen atom in an intense high-frequency Gaussian-pulsed laser field. Investigating the dynamics of the ionization process (for one- and two-photon ionization), we find that only for extremely short pulses, especially for hydrogen, does the system have a significant probability of surviving at the end of the pulse, leading to the phenomenon of atomic stabilization with respect to ionization. We also find that a one-dimensional model has a higher survival probability at the end of a Gaussian pulse, as compared to the three-dimensional hydrogen atom.

  18. [Changes in the chromatin structure of lymphoid cells under the influence of low-intensity extremely high-frequency electromagnetic radiation against the background of inflammatory process].

    PubMed

    Gapeev, A B; Romanova, N A; Chemeris, N K

    2011-01-01

    Using the alkaline single cell gel electrophoresis technique (comet assay), changes in chromatin structure of peripheral blood leukocytes and peritoneal neutrophils have been studied in mice exposed to low-intensity extremely high-frequency electromagnetic radiation (42.2 GHz, 0.1 mW/cm2, 20 min at 1 h after induction of inflammation) against the background of the systemic inflammatory process. It was revealed that the exposure of mice with the developing inflammation leads to a pronounced decrease in the level of DNA damage to peripheral blood leukocytes and peritoneal neutrophils. It is supposed that the changes in the chromatin structure of lymphoid cells have a genoprotective character in the inflammatory process and can underlie the mechanisms of realization of antiinflammatory effects of the electromagnetic radiation.

  19. [The influence of ultrahigh-frequency electromagnetic radiation and low-intensity laser radiation on the body core temperature and basal metabolism in rats with systemic inflammation].

    PubMed

    Zhavoronok, I P; Molchanova, A Iu; Ulashik, V S

    2012-01-01

    The effects of ultrahigh-frequency electromagnetic radiation (UHF EMR) and low-intensity laser irradiation (LILI) on the body and skin temperature, oxygen consumption, production of carbon dioxide and heat release were investigated in the experiments on intact rats and during LPS-induced polyphasic fever. It was found that UHF EMR with the wavelength of 4,9 mm, 5,6 mm or 7,1 mm and LILI with the wavelength of 0.47 microm, 0.67 microm and 0.87 microm caused modulation of basal metabolism and thermal response to systemically administered lipopolysaccharide (LPS). These findings suggest that the most pronounced antipyretic and hypometabolic effects were observed after the treatment with UHF EMR at 7,1 mm and LILI at 470 microm.

  20. A prospective comparison of acute intestinal toxicity following whole pelvic versus small field intensity-modulated radiotherapy for prostate cancer

    PubMed Central

    Kim, Yeon Joo; Park, Jin-hong; Yun, In-Ha; Kim, Young Seok

    2016-01-01

    Purpose To compare the acute intestinal toxicity of whole pelvic (WP) and small field (SF) intensity-modulated radiotherapy (IMRT) for prostate cancer using dosimetric and metabolic parameters as well as clinical findings. Methods Patients who received IMRT in either a definitive or postoperative setting were prospectively enrolled. Target volume and organs at risk including intestinal cavity (IC) were delineated in every patient by a single physician. The IC volume that received a 10–50 Gy dose at 5-Gy intervals (V10–V50) and the percentage of irradiated volume as a fraction of total IC volume were calculated. Plasma citrulline levels, as an objective biological marker, were checked at three time points: baseline and after exposure to 30 Gy and 60 Gy. Results Of the 41 patients, only six experienced grade 1 acute intestinal toxicity. Although all dose–volume parameters were significantly worse following WP than SF IMRT, there was no statistically significant relationship between these dosimetric parameters and clinical symptoms. Plasma citrulline levels did not show a serial decrease by radiotherapy volume difference (WP versus SF) and were not relevant to the irradiated doses. Conclusion Given that WP had comparable acute intestinal toxicities to those associated with SF, WP IMRT appears to be a feasible approach for the treatment of prostate cancer despite dosimetric disadvantages. PMID:27022287

  1. Dosimetric evaluation of a simple planning method for improving intensity-modulated radiotherapy for stage III lung cancer

    PubMed Central

    Lu, Jia-Yang; Lin, Zhu; Zheng, Jing; Lin, Pei-Xian; Cheung, Michael Lok-Man; Huang, Bao-Tian

    2016-01-01

    This study aimed to evaluate the dosimetric outcomes of a base-dose-plan-compensation (BDPC) planning method for improving intensity-modulated radiotherapy (IMRT) for stage III lung cancer. For each of the thirteen included patients, three types of planning methods were applied to obtain clinically acceptable plans: (1) the conventional optimization method (CO); (2) a split-target optimization method (STO), in which the optimization objectives were set higher dose for the target with lung density; (3) the BDPC method, which compensated for the optimization-convergence error by further optimization based on the CO plan. The CO, STO and BDPC methods were then compared regarding conformity index (CI), homogeneity index (HI) of the target, organs at risk (OARs) sparing and monitor units (MUs). The BDPC method provided better HI/CI by 54%/7% on average compared to the CO method and by 38%/3% compared to the STO method. The BDPC method also spared most of the OARs by up to 9%. The average MUs of the CO, STO and BDPC plans were 890, 937 and 1023, respectively. Our results indicated that the BDPC method can effectively improve the dose distribution in IMRT for stage III lung cancer, at the expense of more MUs. PMID:27009235

  2. Feasibility of intensity-modulated radiotherapy combined with gemcitabine and S-1 for patients with pancreatic cancer

    PubMed Central

    KENNOKI, NORIFUMI; NAKAYAMA, HIDETSUGU; NAGAKAWA, YUICHI; HOSOKAWA, YUICHI; ITONAGA, TOMOHIRO; TAJIMA, YU; SHIRAISHI, SACHICA; MIKAMI, RYUJI; TSUCHIDA, AKIHIKO; TOKUUYE, KOICHI

    2016-01-01

    The aim of the present study was to establish whether intensity-modulated radiotherapy (IMRT) with concurrent gemcitabine and S-1 is a feasible treatment option for patients with locally advanced pancreatic ductal adenocarcinoma. Patients with pancreatic ductal adenocarcinoma were prospectively enrolled. An IMRT dose of 50.4 Gy in 28 fractions with concurrent gemcitabine at a dose of 600 mg/m2 and S-1 at a dose of 60 mg were administrated. Adverse events and associated dosimetric factors were assessed. Between February 2012 and January 2014, 17 patients with borderline resectable and 4 with unresectable pancreatic cancer were enrolled. None of the patients experienced grade 3 or worse nausea and vomiting. The planning target volume (≥200 vs. <200 ml) was a statistically significant predictive factor for neutrocytopenia (≥500 vs. 500/µl, P=0.02). Concurrent IMRT with gemcitabine and S-1 for patients with locally advanced pancreatic cancer is feasible, with tolerable hematological toxicities and low gastrointestinal toxicities. PMID:26870355

  3. Use of maximum intensity projections (MIP) for target volume generation in 4DCT scans for lung cancer

    SciTech Connect

    Underberg, Rene W.M.; Lagerwaard, Frank J. . E-mail: fj.lagerwaard@vumc.nl; Slotman, Ben J.; Cuijpers, Johan P.; Senan, Suresh

    2005-09-01

    Purpose: Single four-dimensional CT (4DCT) scans reliably capture intrafractional tumor mobility for radiotherapy planning, but generating internal target volumes (ITVs) requires the contouring of gross tumor volumes (GTVs) in up to 10 phases of a 4DCT scan, as is routinely performed in our department. We investigated the use of maximum intensity projection (MIP) protocols for rapid generation of ITVs. Methods and Materials: 4DCT data from a mobile phantom and from 12 patients with Stage I lung cancer were analyzed. A single clinician contoured GTVs in all respiratory phases of a 4DCT, as well as in three consecutive phases selected for respiratory gating. MIP images were generated from both phantom and patient data, and ITVs were derived from encompassing volumes of the respective GTVs. Results: In the phantom study, the ratio between ITVs generated from all 10 phases and those from MIP scans was 1.04. The corresponding center of mass of both ITVs differed by less than 1 mm. In scans from patients, good agreement was observed between ITVs derived from 10 and 3 (gating) phases and corresponding MIPs, with ratios of 1.07 {+-} 0.05 and 0.98 {+-} 0.05, respectively. In addition, the center of mass of the respective ITVs differed by only 0.4 and 0.5 mm. Conclusion: MIPs are a reliable clinical tool for generating ITVs from 4DCT data sets, thereby permitting rapid assessment of mobility for both gated and nongated 4D radiotherapy in lung cancer.

  4. Flattening Filter-Free Beams in Intensity-Modulated Radiotherapy and Volumetric Modulated Arc Therapy for Sinonasal Cancer

    PubMed Central

    Huang, Bao-Tian

    2016-01-01

    Purpose To evaluate the dosimetric impacts of flattening filter-free (FFF) beams in intensity-modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) for sinonasal cancer. Methods For fourteen cases, IMRT and VMAT planning was performed using 6-MV photon beams with both conventional flattened and FFF modes. The four types of plans were compared in terms of target dose homogeneity and conformity, organ-at-risk (OAR) sparing, number of monitor units (MUs) per fraction, treatment time and pure beam-on time. Results FFF beams led to comparable target dose homogeneity, conformity, increased number of MUs and lower doses to the spinal cord, brainstem and normal tissue, compared with flattened beams in both IMRT and VMAT. FFF beams in IMRT resulted in improvements by up to 5.4% for sparing of the contralateral optic structures, with shortened treatment time by 9.5%. However, FFF beams provided comparable overall OAR sparing and treatment time in VMAT. With FFF mode, VMAT yielded inferior homogeneity and superior conformity compared with IMRT, with comparable overall OAR sparing and significantly shorter treatment time. Conclusions Using FFF beams in IMRT and VMAT is feasible for the treatment of sinonasal cancer. Our results suggest that the delivery mode of FFF beams may play an encouraging role with better sparing of contralateral optic OARs and treatment efficiency in IMRT, but yield comparable results in VMAT. PMID:26734731

  5. Pulsed high-intensity focused ultrasound therapy enhances targeted delivery of cetuximab to colon cancer xenograft model in mice.

    PubMed

    Park, Min Jung; Kim, Young-Sun; Yang, Jehoon; Sun, Woo Chul; Park, Hajan; Chae, Sun Young; Namgung, Mi-Sun; Choi, Kyu-Sil

    2013-02-01

    Our aim was to evaluate whether pulsed high-intensity focused ultrasound (HIFU) therapy enhances the effect of an epidermal growth factor receptor-targeted chemotherapeutic drug, cetuximab, in treating human colon cancer xenografts in a mouse model. Balb/c nude mice with subcutaneous xenografts of HT-29 cells were randomly categorized into control (n = 9), pulsed HIFU alone (n = 10), cetuximab monotherapy (n = 8) or combined pulsed HIFU and cetuximab therapy (n = 9) group. Cetuximab, pulsed HIFU therapy, or both were administered three times per week starting from day 8 after tumor cell injection. Based on tumor growth curves up to 34 days, the combination therapy group showed more suppressed tumor growth than all other groups (p < 0.05). The final relative tumor volumes were 5.4 ± 2.1, 5.2 ± 1.3, 4.8 ± 1.8, and 3.1 ± 0.9 for control, pulsed HIFU alone, cetuximab monotherapy, and combination therapy groups, respectively. In conclusion, pulsed HIFU therapy appears to enhance the anti-tumor effect of epidermal growth factor receptor-targeted cetuximab on human colon cancer xenograft models in mice. PMID:23219035

  6. Dosimetric evaluation of a simple planning method for improving intensity-modulated radiotherapy for stage III lung cancer.

    PubMed

    Lu, Jia-Yang; Lin, Zhu; Zheng, Jing; Lin, Pei-Xian; Cheung, Michael Lok-Man; Huang, Bao-Tian

    2016-01-01

    This study aimed to evaluate the dosimetric outcomes of a base-dose-plan-compensation (BDPC) planning method for improving intensity-modulated radiotherapy (IMRT) for stage III lung cancer. For each of the thirteen included patients, three types of planning methods were applied to obtain clinically acceptable plans: (1) the conventional optimization method (CO); (2) a split-target optimization method (STO), in which the optimization objectives were set higher dose for the target with lung density; (3) the BDPC method, which compensated for the optimization-convergence error by further optimization based on the CO plan. The CO, STO and BDPC methods were then compared regarding conformity index (CI), homogeneity index (HI) of the target, organs at risk (OARs) sparing and monitor units (MUs). The BDPC method provided better HI/CI by 54%/7% on average compared to the CO method and by 38%/3% compared to the STO method. The BDPC method also spared most of the OARs by up to 9%. The average MUs of the CO, STO and BDPC plans were 890, 937 and 1023, respectively. Our results indicated that the BDPC method can effectively improve the dose distribution in IMRT for stage III lung cancer, at the expense of more MUs. PMID:27009235

  7. Salvage robotic-assisted laparoscopic radical prostatectomy following failed primary high-intensity focussed ultrasound treatment for localised prostate cancer.

    PubMed

    Murphy, Declan G; Pedersen, John; Costello, Anthony J

    2008-09-01

    We report the first case of salvage robotic-assisted laparoscopic radical prostatectomy (RALP) following failed primary high-intensity focussed ultrasound (HIFU) for localised carcinoma of the prostate. A 66-year-old male with a presenting prostate-specific antigen (PSA) of 5 ng/ml was diagnosed with T1c Gleason 3 + 4 prostate cancer. He underwent transurethral resection of the prostate and HIFU. His PSA dropped to 2.0 ng/ml and repeat biopsy revealed upgrading of his prostate cancer to Gleason 4 + 3. He was referred to us for a second opinion and, following discussion of his options, he underwent RALP. The total operative time was 159 min. There were no intra- or postoperative complications. He was discharged on postoperative day two and was fully continent 10 days following removal of his catheter. His PSA remained undetectable 6 months postoperatively. Salvage RALP was feasible in this case with good functional and short-term oncological outcomes for the patient. PMID:27628262

  8. Participation in the SUCCESS-A Trial Improves Intensity and Quality of Care for Patients with Primary Breast Cancer

    PubMed Central

    Andergassen, U.; Kasprowicz, N. S.; Hepp, P.; Schindlbeck, C.; Harbeck, N.; Kiechle, M.; Sommer, H.; Beckmann, M. W.; Friese, K.; Janni, W.; Rack, B.; Scholz, C.

    2013-01-01

    The SUCCESS-A trial is a prospective, multicenter, phase III clinical trial for high-risk primary breast cancer. It compares disease-free survival after randomization in patients treated with fluorouracil, epirubicin and cyclophosphamide followed by 3 cycles of docetaxel (FEC-D) with that of patients treated with 3 cycles of FEC followed by 3 cycles of gemcitabine and docetaxel (FEC-DG). After a second randomization patients were treated with zoledronate for 2 or 5 years. A total of 251 centers took part in the trial and 3754 patients were recruited over a period of 18 months which ended in March 2007. In a questionnaire-based survey we investigated the impact of enrollment in the trial on patient care, the choice of chemotherapy protocol and access to current oncologic information as well as overall satisfaction in the respective centers. Analysis of the 78 questionnaires returned showed that 40 % of the centers had never previously enrolled patients with these indications in clinical studies. Prior to participating in the study, 4 % of the centers prescribed CMF or other protocols in patients with high-primary breast cancer risk, 46 % administered anthracycline-based chemotherapy and 50 % gave taxane-based chemotherapy. Around half of the participating centers noted that intensity of care and overall quality of care became even better and that access to breast cancer-specific information improved through participation in the trial. After their experience with the SUCCESS-A trial, all of the centers stated that they were prepared to enroll patients in clinical phase III trials again in the future. These data indicate that both patients and physicians benefit from clinical trials, as enrollment improves treatment strategies and individual patient care, irrespective of study endpoints. PMID:24771886

  9. Helical Tomotherapy Versus Conventional Intensity-Modulated Radiation Therapy for Primary Chemoradiation in Cervical Cancer Patients: An Intraindividual Comparison

    SciTech Connect

    Marnitz, Simone; Lukarski, Dusko; Koehler, Christhardt; Wlodarczyk, Waldemar; Ebert, Andreas; Budach, Volker; Schneider, Achim; Stromberger, Carmen

    2011-10-01

    Purpose: To compare intensity-modulated radiotherapy (IMRT) delivered by helical tomotherapy (HT) with conventional IMRT for primary chemoradiation in cervical cancer patients. Methods and Materials: Twenty cervical cancer patients undergoing primary chemoradiation received radiation with HT; 10 patients underwent pelvic irradiation (PEL) and 10 extended-field irradiation (EXT). For treatment planning, the simultaneously integrated boost (SIB) concept was applied. Tumor, pelvic, with or without para-aortic lymph nodes were defined as planning target volume A (PTV-A) with a prescribed dose of 1.8/50.4 Gy (28 fractions). The SIB dose for the parametrium (PTV-B), was 2.12/59.36 Gy. The lower target constraints were 95% of the prescribed dose in 95% of the target volume, and the upper dose constraint was 107%. The irradiated small-bowel volumes were kept as low as possible. For every HT plan, a conventional IMRT plan was calculated and compared with regard to dose-volume histogram, conformity index and conformity number, and homogeneity index. Results: Both techniques allowed excellent target volume coverage and sufficient SB sparing. Conformity index and conformity number results for both PTV-A and PTV-B, homogeneity index for PTV-B, and SB sparing for V45, V50, Dmax, and D1% were significantly better with HT. SB sparing was significantly better for conventional IMRT at low doses (V10). Conclusions: Both HT and conventional IMRT provide optimal treatment of cervical cancer patients. The HT technique was significantly favored with regard to target conformity, homogeneity, and SB sparing. Randomized trials are needed to assess the oncological outcome, toxicity, and clinical relevance of these differences.

  10. Limited Advantages of Intensity-Modulated Radiotherapy Over 3D Conformal Radiation Therapy in the Adjuvant Management of Gastric Cancer

    SciTech Connect

    Alani, Shlomo; Soyfer, Viacheslav; Strauss, Natan; Schifter, Dan; Corn, Benjamin W.

    2009-06-01

    Purpose: Although chemoradiotherapy was considered the standard adjuvant treatment for gastric cancer, a recent Phase III trial (Medical Research Council Adjuvant Gastric Infusional Chemotherapy [MAGIC]) did not include radiotherapy in the randomization scheme because it was considered expendable. Given radiotherapy's potential, efforts needed to be made to optimize its use for treating gastric cancer. We assessed whether intensity-modulated radiotherapy (IMRT) could improve upon our published results in patients treated with three-dimensional (3D) conformal therapy. Methods and Materials: Fourteen patients with adenocarcinoma of the stomach were treated with adjuvant chemoradiotherapy using a noncoplanar four-field arrangement. Subsequently, a nine-field IMRT plan was designed using a CMS Xio IMRT version 4.3.3 module. Two IMRT beam arrangements were evaluated: beam arrangement 1 consisted of gantry angles of 0 deg., 53 deg., 107 deg., 158 deg., 204 deg., 255 deg., and 306 deg.. Beam arrangement 2 consisted of gantry angles of 30 deg., 90 deg., 315 deg., and 345 deg.; a gantry angle of 320 deg./couch, 30 deg.; and a gantry angle of 35{sup o}/couch, 312{sup o}. Both the target volume coverage and the dose deposition in adjacent critical organs were assessed in the plans. Dose-volume histograms were generated for the clinical target volume, kidneys, spine, and liver. Results: Comparison of the clinical target volumes revealed satisfactory coverage by the 95% isodose envelope using either IMRT or 3D conformal therapy. However, IMRT was only marginally better than 3D conformal therapy at protecting the spine and kidneys from radiation. Conclusions: IMRT confers only a marginal benefit in the adjuvant treatment of gastric cancer and should be used only in the small subset of patients with risk factors for kidney disease or those with a preexisting nephropathy.

  11. A Fully Automated Method for CT-on-Rails-Guided Online Adaptive Planning for Prostate Cancer Intensity Modulated Radiation Therapy

    SciTech Connect

    Li, Xiaoqiang; Quan, Enzhuo M.; Li, Yupeng; Pan, Xiaoning; Zhou, Yin; Wang, Xiaochun; Du, Weiliang; Kudchadker, Rajat J.; Johnson, Jennifer L.; Kuban, Deborah A.; Lee, Andrew K.; Zhang, Xiaodong

    2013-08-01

    Purpose: This study was designed to validate a fully automated adaptive planning (AAP) method which integrates automated recontouring and automated replanning to account for interfractional anatomical changes in prostate cancer patients receiving adaptive intensity modulated radiation therapy (IMRT) based on daily repeated computed tomography (CT)-on-rails images. Methods and Materials: Nine prostate cancer patients treated at our institution were randomly selected. For the AAP method, contours on each repeat CT image were automatically generated by mapping the contours from the simulation CT image using deformable image registration. An in-house automated planning tool incorporated into the Pinnacle treatment planning system was used to generate the original and the adapted IMRT plans. The cumulative dose–volume histograms (DVHs) of the target and critical structures were calculated based on the manual contours for all plans and compared with those of plans generated by the conventional method, that is, shifting the isocenters by aligning the images based on the center of the volume (COV) of prostate (prostate COV-aligned). Results: The target coverage from our AAP method for every patient was acceptable, while 1 of the 9 patients showed target underdosing from prostate COV-aligned plans. The normalized volume receiving at least 70 Gy (V{sub 70}), and the mean dose of the rectum and bladder were reduced by 8.9%, 6.4 Gy and 4.3%, 5.3 Gy, respectively, for the AAP method compared with the values obtained from prostate COV-aligned plans. Conclusions: The AAP method, which is fully automated, is effective for online replanning to compensate for target dose deficits and critical organ overdosing caused by interfractional anatomical changes in prostate cancer.

  12. Grading xerostomia by physicians or by patients after intensity-modulated radiotherapy of head-and-neck cancer

    SciTech Connect

    Meirovitz, Amichay; Murdoch-Kinch, Carol Anne; Schipper, Mathew; Pan, Charlie; Eisbruch, Avraham . E-mail: eisbruch@umich.edu

    2006-10-01

    Purpose: To assess observer-based vs. patient self-reported scoring of xerostomia after intensity-modulated radiotherapy (IMRT) of head-and-neck (HN) cancer. Methods: A total of 38 patients who had received IMRT for HN cancer underwent xerostomia evaluations 6 to 24 months after completion of therapy using three methods each time: (1) Grading by 3 observers according to the Radiotherapy Oncology Group/European Organization for Research and Therapy of Cancer (RTOG/EORTC) system; (2) patient self-reported validated xerostomia questionnaire (XQ); and (3) major salivary gland flow measurements. Results: The interobserver agreement regarding the RTOG/EORTC grades was moderate: {kappa}-coefficient 0.54 (95% CI = 0.31-0.76). The correlations between the average RTOG/EORTC grades and the salivary flow rates were not statistically significant. A trend for significant correlation was observed between these grades and the percent (relative to the pretherapy) nonstimulated salivary flow rates (p = 0.07), but not with the percent stimulated flow rates. Better correlations were found between grading made more than the median time (15 min) after the last liquid sipping and the nonstimulated (but not the stimulated) flows compared with grading made shortly after sipping. In contrast, significant correlations were found between the XQ scores and the nonstimulated (p < 0.005) and the stimulated (p < 0.005) salivary flow rates, as well as with the percentages of the corresponding pretherapy values (p = 0.002 and 0.038, respectively). No significant correlation was found between the RTOG/EORTC grades and the XQ scores. The observer-based grades underestimated the severity of xerostomia compared with the patient self-reported scores. Conclusions: Patient self-reported, rather than physician-assessed scores, should be the main end points in evaluating xerostomia.

  13. Long-Term Breast Cancer Patient Outcomes After Adjuvant Radiotherapy Using Intensity-Modulated Radiotherapy or Conventional Tangential Radiotherapy

    PubMed Central

    Yang, Jen-Fu; Lee, Meei-Shyuan; Lin, Chun-Shu; Chao, Hsing-Lung; Chen, Chang-Ming; Lo, Cheng-Hsiang; Fan, Chao-Yueh; Tsao, Chih-Cheng; Huang, Wen-Yen

    2016-01-01

    Abstract The aim of the article is to analyze breast cancer patient clinical outcomes after long-term follow-up using intensity-modulated radiotherapy (IMRT) or conventional tangential radiotherapy (cRT). We retrospectively reviewed patients with stage 0–III breast cancer who received breast conserving therapy between April 2004 and December 2007. Of the 234 patients, 103 (44%) were treated with IMRT and 131 (56%) were treated with cRT. A total prescription dose of 45 to 50 Gy (1.8–2 Gy per fraction) was delivered to the whole breast. A 14 Gy boost dose was delivered in 7 fractions. The median follow-up was 8.2 years. Five of 131 (3.8%) cRT-treated patients and 2 of 103 (1.9%) IMRT-treated patients had loco-regional failure. The 8-year loco-regional failure-free survival rates were 96.7% and 97.6% (P = 0.393) in the cRT and IMRT groups, respectively, whereas the 8-year disease-free survival (DFS) rates were 91.2% and 93.1%, respectively (P = 0.243). Patients treated with IMRT developed ≥ grade 2 acute dermatitis less frequently than patients treated with cRT (40.8% vs 56.5%; P = 0.017). There were no differences in late toxicity. IMRT reduces ≥ grade 2 acute skin toxicity. Local control, DFS, and overall survival were equivalent with IMRT and cRT. IMRT can be considered a standard technique for breast cancer treatment. PMID:26986158

  14. Critical determination of the frequency of c-erbB-2 amplification in breast cancer.

    PubMed Central

    Hubbard, A. L.; Doris, C. P.; Thompson, A. M.; Chetty, U.; Anderson, T. J.

    1994-01-01

    Tissues from 323 methacarn-fixed and paraffin-embedded breast cancers were assessed for c-erbB-2 gene amplification by differential polymerase chain reaction (dPCR). The sensitivity of dPCR was ascertained using cell lines with c-erbB-2 amplification, and the relationship between dPCR ratio value and gene copy number was established. In clinical material the technique was not affected by the DNA contribution of normal tissue elements or by cancer DNA ploidy change. c-erbB-2 gene amplification was detected in 55% of invasive cancers and in 66% of in situ cancers. c-erbB-2 protein overexpression in breast cancer cells, as determined by specific immunohistochemistry, was only detected in 11% of invasive cancers and 43% of in situ cancers. Comparisons show that a substantial number of cancers with c-erbB-2 amplification lack detectable protein overexpression. This illustrates the complex nature of c-erbB-2 gene disregulation in cancer and suggests that multiple combinations of biological events and consequences are possible. Images Figure 3 PMID:7915911

  15. Comparable effects of low-intensity electromagnetic irradiation at the frequency of 51.8 and 53 GHz and antibiotic ceftazidime on Lactobacillus acidophilus growth and survival.

    PubMed

    Soghomonyan, Diana; Trchounian, Armen

    2013-01-01

    The effects of low-intensity electromagnetic irradiation (EMI) with the frequencies of 51.8 and 53 GHz on Lactobacillus acidophilus growth and survival were revealed. These effects were compared with antibacterial effects of antibiotic ceftazidime. Decrease in bacterial growth rate by EMI was comparable with the inhibitory effect of ceftazidime (minimal inhibitory concentration-16 μM) and no enhanced action was observed with combined effects of EMI and the antibiotic. However, EMI-enhanced antibiotic inhibitory effect on bacterial survival. The kinetics of the bacterial suspension oxidation-reduction potential up to 24 h of the growth was changed by EMI and ceftazidime. The changes were more strongly expressed by combined effects of EMI and antibiotic especially up to 12 h. Moreover, EMI did not change overall energy (glucose)-dependent H(+) efflux across the membrane but it increased N,N'-dicyclohexylcarbodiimide (DCCD)-inhibited H(+) efflux. In contrast, this EMI in combination with ceftazidime decreased DCCD-sensitive H(+) efflux. Low-intensity EMI had inhibitory effect on L. acidophilus bacterial growth and survival. The effect on bacterial survival was more significant in the combination with ceftazidime. The H(+)-translocating F 0 F 1-ATPase, for which DCCD is specific inhibitor, might be a target for EMI and ceftazidime. The revealed bactericide effects on L. acidophilus can be applied in biotechnology, food producing and safety technology.

  16. Self-regulatory mode (locomotion and assessment), well-being (subjective and psychological), and exercise behavior (frequency and intensity) in relation to high school pupils’ academic achievement

    PubMed Central

    Jimmefors, Alexander; Mousavi, Fariba; Adrianson, Lillemor; Rosenberg, Patricia; Archer, Trevor

    2015-01-01

    Background. Self-regulation is the procedure implemented by an individual striving to reach a goal and consists of two inter-related strategies: assessment and locomotion. Moreover, both subjective and psychological well-being along exercise behaviour might also play a role on adolescents academic achievement. Method. Participants were 160 Swedish high school pupils (111 boys and 49 girls) with an age mean of 17.74 (sd = 1.29). We used the Regulatory Mode Questionnaire to measure self-regulation strategies (i.e., locomotion and assessment). Well-being was measured using Ryff’s Psychological Well-Being Scales short version, the Temporal Satisfaction with Life Scale, and the Positive Affect and Negative Affect Schedule. Exercise behaviour was self-reported using questions pertaining to frequency and intensity of exercise compliance. Academic achievement was operationalized through the pupils’ mean value of final grades in Swedish, Mathematics, English, and Physical Education. Both correlation and regressions analyses were conducted. Results. Academic achievement was positively related to assessment, well-being, and frequent/intensive exercise behaviour. Assessment was, however, negatively related to well-being. Locomotion on the other hand was positively associated to well-being and also to exercise behaviour. Conclusions. The results suggest a dual (in)direct model to increase pupils’ academic achievement and well-being—assessment being directly related to higher academic achievement, while locomotion is related to frequently exercising and well-being, which in turn, increase academic achievement. PMID:25861553

  17. Self-regulatory mode (locomotion and assessment), well-being (subjective and psychological), and exercise behavior (frequency and intensity) in relation to high school pupils' academic achievement.

    PubMed

    Garcia, Danilo; Jimmefors, Alexander; Mousavi, Fariba; Adrianson, Lillemor; Rosenberg, Patricia; Archer, Trevor

    2015-01-01

    Background. Self-regulation is the procedure implemented by an individual striving to reach a goal and consists of two inter-related strategies: assessment and locomotion. Moreover, both subjective and psychological well-being along exercise behaviour might also play a role on adolescents academic achievement. Method. Participants were 160 Swedish high school pupils (111 boys and 49 girls) with an age mean of 17.74 (sd = 1.29). We used the Regulatory Mode Questionnaire to measure self-regulation strategies (i.e., locomotion and assessment). Well-being was measured using Ryff's Psychological Well-Being Scales short version, the Temporal Satisfaction with Life Scale, and the Positive Affect and Negative Affect Schedule. Exercise behaviour was self-reported using questions pertaining to frequency and intensity of exercise compliance. Academic achievement was operationalized through the pupils' mean value of final grades in Swedish, Mathematics, English, and Physical Education. Both correlation and regressions analyses were conducted. Results. Academic achievement was positively related to assessment, well-being, and frequent/intensive exercise behaviour. Assessment was, however, negatively related to well-being. Locomotion on the other hand was positively associated to well-being and also to exercise behaviour. Conclusions. The results suggest a dual (in)direct model to increase pupils' academic achievement and well-being-assessment being directly related to higher academic achievement, while locomotion is related to frequently exercising and well-being, which in turn, increase academic achievement. PMID:25861553

  18. Four-Week Course of Radiation for Breast Cancer Using Hypofractionated Intensity Modulated Radiation Therapy With an Incorporated Boost

    SciTech Connect

    Freedman, Gary M. . E-mail: Gary.Freedman@FCCC.edu; Anderson, Penny R.; Goldstein, Lori J.; Ma Changming; Li Jinsheng; Swaby, Ramona F.; Litwin, Samuel; Watkins-Bruner, Deborah; Sigurdson, Elin R.; Morrow, Monica

    2007-06-01

    Purpose: Standard radiation for early breast cancer requires daily treatment for 6 to 7 weeks. This is an inconvenience to many women, and for some a barrier for breast conservation. We present the acute toxicity of a 4-week course of hypofractionated radiation. Methods and Materials: A total of 75 patients completed radiation on a Phase II trial approved by the hospital institutional review board. Eligibility criteria were broad to include any patient normally eligible for standard radiation: age {>=}18 years, invasive or in situ cancer, American Joint Committee on Cancer Stage 0 to II, breast-conserving surgery, and any systemic therapy not given concurrently. The median age was 52 years (range, 31-81 years). Of the patients, 15% had ductal carcinoma in situ, 67% T1, and 19% T2; 71% were N0, 17% N1, and 12% NX. Chemotherapy was given before radiation in 44%. Using photon intensity-modulated radiation therapy and incorporated electron beam boost, the whole breast received 45 Gy and the lumpectomy bed 56 Gy in 20 treatments over 4 weeks. Results: The maximum acute skin toxicity by the end of treatment was Grade 0 in 9 patients (12%), Grade 1 in 49 (65%) and Grade 2 in 17 (23%). There was no Grade 3 or higher skin toxicity. After radiation, all Grade 2 toxicity had resolved by 6 weeks. Hematologic toxicity was Grade 0 in most patients except for Grade 1 neutropenia in 2 patients, and Grade 1 anemia in 11 patients. There were no significant differences in baseline vs. 6-week posttreatment patient-reported or physician-reported cosmetic scores. Conclusions: This 4-week course of postoperative radiation using intensity-modulated radiation therapy is feasible and is associated with acceptable acute skin toxicity and quality of life. Long-term follow-up data are needed. This radiation schedule may represent an alternative both to longer 6-week to 7-week standard whole-breast radiation and more radically shortened 1-week, partial-breast treatment schedules.

  19. Ion heating, burnout of the high-frequency field, and ion sound generation under the development of a modulation instability of an intense Langmuir wave in a plasma

    SciTech Connect

    Kirichok, A. V. Kuklin, V. M.; Pryimak, A. V.; Zagorodny, A. G.

    2015-09-15

    The development of one-dimensional parametric instabilities of intense long plasma waves is considered in terms of the so-called hybrid models, with electrons being treated as a fluid and ions being regarded as particles. The analysis is performed for both cases when the average plasma field energy is lower (Zakharov's hybrid model—ZHM) or greater (Silin's hybrid model—SHM) than the plasma thermal energy. The efficiency of energy transfer to ions and to ion perturbations under the development of the instability is considered for various values of electron-to-ion mass ratios. The energy of low-frequency oscillations (ion-sound waves) is found to be much lower than the final ion kinetic energy. We also discuss the influence of the changes in the damping rate of the high-frequency (HF) field on the instability development. The decrease of the absorption of the HF field inhibits the HF field burnout within plasma density cavities and gives rise to the broadening of the HF spectrum. At the same time, the ion velocity distribution tends to the normal distribution in both ZHM and SHM.

  20. Measurements of ion cyclotron range of frequencies mode converted wave intensity with phase contrast imaging in Alcator C-Mod and comparison with full-wave simulations

    SciTech Connect

    Tsujii, N.; Porkolab, M.; Bonoli, P. T.; Lin, Y.; Wright, J. C.; Wukitch, S. J.; Jaeger, E. F.; Green, D. L.; Harvey, R. W.

    2012-08-15

    Radio frequency waves in the ion cyclotron range of frequencies (ICRF) are widely used to heat tokamak plasmas. In ICRF heating schemes involving multiple ion species, the launched fast waves convert to ion cyclotron waves or ion Bernstein waves at the two-ion hybrid resonances. Mode converted waves are of interest as actuators to optimise plasma performance through current drive and flow drive. In order to describe these processes accurately in a realistic tokamak geometry, numerical simulations are essential, and it is important that these codes be validated against experiment. In this study, the mode converted waves were measured using a phase contrast imaging technique in D-H and D-{sup 3}He plasmas. The measured mode converted wave intensity in the D-{sup 3}He mode conversion regime was found to be a factor of {approx}50 weaker than the full-wave predictions. The discrepancy was reduced in the hydrogen minority heating regime, where mode conversion is weaker.

  1. Ion heating, burnout of the high-frequency field, and ion sound generation under the development of a modulation instability of an intense Langmuir wave in a plasma

    NASA Astrophysics Data System (ADS)

    Kirichok, A. V.; Kuklin, V. M.; Pryimak, A. V.; Zagorodny, A. G.

    2015-09-01

    The development of one-dimensional parametric instabilities of intense long plasma waves is considered in terms of the so-called hybrid models, with electrons being treated as a fluid and ions being regarded as particles. The analysis is performed for both cases when the average plasma field energy is lower (Zakharov's hybrid model—ZHM) or greater (Silin's hybrid model—SHM) than the plasma thermal energy. The efficiency of energy transfer to ions and to ion perturbations under the development of the instability is considered for various values of electron-to-ion mass ratios. The energy of low-frequency oscillations (ion-sound waves) is found to be much lower than the final ion kinetic energy. We also discuss the influence of the changes in the damping rate of the high-frequency (HF) field on the instability development. The decrease of the absorption of the HF field inhibits the HF field burnout within plasma density cavities and gives rise to the broadening of the HF spectrum. At the same time, the ion velocity distribution tends to the normal distribution in both ZHM and SHM.

  2. [Effect of coherent extremely high-frequency and low-intensity electromagnetic radiation on the activity of membrane systems in Escherichia coli].

    PubMed

    Tadevosian, A; Trchunian, A

    2009-01-01

    It has been shown that the exposure of wild-type Escherichia coli K12 bacteria grown in anaerobic conditions upon fermentation of glucose to coherent extremely high-frequency (51.8 and 53 GHz) electromagnetic radiation (EMR) or millimeter waves (wavelength 5.8 to 6.7 mm) of low intensity (flux capacity 0.06 mW/cm2) caused a marked decrease in energy-dependent and N,N'-dicyclohexylcarbodiimide- or azide-sensitive proton and potassium ions transport fluxes through the membrane, including proton fluxes via proton F0F1-ATPase and through the potassium uptake Trk system, correspondingly. K+ uptake was less for the E. coli mutant Trk 1110. The rate of molecular hydrogen production by formate hydrogen lyase 2 is strongly inhibited. The results indicate that the bacterial effect of coherent extremely high-frequency EMR includes changes in the activity of membrane transport and enzymatic systems in which the F0F1-ATPase plays a key role.

  3. Changes in the Intensity and Frequency of Atmospheric Blocking and Associated Heat Waves During Northern Summer Over Eurasia in the CMIP5 Model Simulations

    NASA Technical Reports Server (NTRS)

    Kim, Kyu-Myong; Lau, K. M.; Wu, H. T.; Kim, Maeng-Ki; Cho, Chunho

    2012-01-01

    The Russia heat wave and wild fires of the summer of 2010 was the most extreme weather event in the history of the country. Studies show that the root cause of the 2010 Russia heat wave/wild fires was an atmospheric blocking event which started to develop at the end of June and peaked around late July and early August. Atmospheric blocking in the summer of 2010 was anomalous in terms of the size, duration, and the location, which shifted to the east from the normal location. This and other similar continental scale severe summertime heat waves and blocking events in recent years have raised the question of whether such events are occurring more frequently and with higher intensity in a warmer climate induced by greenhouse gases. We studied the spatial and temporal distributions of the occurrence and intensity of atmospheric blocking and associated heat waves for northern summer over Eurasia based on CMIPS model simulations. To examine the global warming induced change of atmospheric blocking and heat waves, experiments for a high emissions scenario (RCP8.S) and a medium mitigation scenario (RCP4.S) are compared to the 20th century simulations (historical). Most models simulate the mean distributions of blockings reasonably well, including major blocking centers over Eurasia, northern Pacific, and northern Atlantic. However, the models tend to underestimate the number of blockings compared to MERRA and NCEPIDOE reanalysis, especially in western Siberia. Models also reproduced associated heat waves in terms of the shifting in the probability distribution function of near surface temperature. Seven out of eight models used in this study show that the frequency of atmospheric blocking over the Europe will likely decrease in a warmer climate, but slightly increase over the western Siberia. This spatial pattern resembles the blocking in the summer of 2010, indicating the possibility of more frequent occurrences of heat waves in western Siberia. In this talk, we will also

  4. Age related vascular endothelial function following lifelong sedentariness: positive impact of cardiovascular conditioning without further improvement following low frequency high intensity interval training

    PubMed Central

    Grace, Fergal M.; Herbert, Peter; Ratcliffe, John W.; New, Karl J.; Baker, Julien S.; Sculthorpe, Nicholas F.

    2015-01-01

    Abstract Aging is associated with diffuse impairments in vascular endothelial function and traditional aerobic exercise is known to ameliorate these changes. High intensity interval training (HIIT) is effective at improving vascular function in aging men with existing disease, but its effectiveness remains to be demonstrated in otherwise healthy sedentary aging. However, the frequency of commonly used HIIT protocols may be poorly tolerated in older cohorts. Therefore, the present study investigated the effectiveness of lower frequency HIIT (LfHIIT) on vascular function in a cohort of lifelong sedentary (SED; n =22, age 62.7 ± 5.2 years) men compared with a positive control group of lifelong exercisers (LEX; n = 17, age 61.1 ± 5.4 years). The study consisted of three assessment phases; enrolment to the study (Phase A), following 6 weeks of conditioning exercise in SED (Phase B) and following 6 weeks of low frequency HIIT in both SED and LEX (LfHIIT; Phase C). Conditioning exercise improved FMD in SED (3.4 ± 1.5% to 4.9 ± 1.1%; P <0.01) such that the difference between groups on enrolment (3.4 ± 1.5% vs. 5.3 ± 1.4%; P <0.01) was abrogated. This was maintained but not further improved following LfHIIT in SED whilst FMD remained unaffected by LfHIIT in LEX. In conclusion, LfHIIT is effective at maintaining improvements in vascular function achieved during conditioning exercise in SED. LfHIIT is a well‐tolerated and effective exercise mode for reducing cardiovascular risk and maintaining but does not improve vascular function beyond that achieved by conditioning exercise in aging men, irrespective of fitness level. PMID:25626864

  5. Signal to Noise Ratio Estimation for a Space-borne Swept-Frequency Intensity-Modulated CO2 Laser Absorption Spectrometer

    NASA Astrophysics Data System (ADS)

    Chen, S.; Lin, B.; Petway, L. B.; Ismail, S.; Campbell, J. F.; Bai, Y.; Harrison, F. W.; Refaat, T. F.; Obland, M. D.; Meadows, B.; Browell, E. V.

    2014-12-01

    The Signal to Noise Ratio (SNR) in the digital lock-in detection for a space-borne swept-frequency Intensity-Modulated Continuous-Wave (IM-CW) CO2 Laser Absorption Spectrometer (LAS) has a direct influence on the accuracy of the CO2 measurement. According to the Maximum Likelihood Estimation (MLE) method, we have theoretically analyzed a linear swept-frequency sine wave signal in an additive high Gaussian-distributed noise with a constant variance, which is a good approximation for the detector-noise-limited system or the solar background noise dominated space-borne IM-CW CO2 LAS. The general MLE equations for the amplitude and the phase of the swept-frequency IM_CW signal have been generated and solved by a nonlinear optimization procedure. The variances of the amplitude and the phase have been obtained by using the Cramer-Rao lower bound, a lower bound on the variance of the estimated parameters. Under the large sampling numbers, the SNR, signal amplitude divided by the square-root of the amplitude variance, increases as the square-root of the total sampling numbers. Thousands of numerical simulations with randomly generated uniform distributed Gaussian noise were completed for the statistical verification of the estimation. The estimation has also been applied to a space-borne IM-CW CO2 LAS with typical parameters under averaged daytime solar background to confirm the feasibilities of the instrument design of the space-borne IM-CW CO2 LAS.

  6. Frequency and Correlates of Posttraumatic-Stress-Disorder-Like Symptoms after Treatment for Breast Cancer.

    ERIC Educational Resources Information Center

    Cordova, Matthew J.; And Others

    1995-01-01

    Assessed Quality Of Life (QOL) and symptoms similar to posttraumatic stress disorder (PTSD) in women posttreatment for breast cancer. Negatively related PTSD symptomatology to QOL, income, and age. Time since treatment, type of cytotoxic treatment, and stage of disease were unrelated to PTSD symptoms. Suggests that in breast cancer survivors,…

  7. Liposome-mediated transfection of wild-type P53 DNA into human prostate cancer cells is improved by low-frequency ultrasound combined with microbubbles

    PubMed Central

    BAI, WEN-KUN; ZHANG, WEI; HU, BING; YING, TAO

    2016-01-01

    Prostate cancer is a common type of cancer in elderly men. The aim of the present study was to evaluate the effects of ultrasound exposure in combination with SonoVue microbubbles on liposome-mediated transfection of wild-type P53 genes into human prostate cancer cells. PC-3 human prostate cancer cells were exposed to ultrasound; duty cycle was controlled at 20% (2 sec on, 8 sec off) for 5 min with and without SonoVue microbubble echo-contrast agent using a digital sonifier (frequency, 21 kHz; intensity, 46 mW/cm2). The cells were divided into eight groups, as follows: Group A (SonoVue + wild-type P53), group B (ultrasound + wild-type P53), group C (SonoVue + ultrasound + wild-type P53), group D (liposome + wild-type P53), group E (liposome + SonoVue + wild-type P53), group F (liposome + wild-type P53 + ultrasound), group G (liposome + wild-type P53 + ultrasound + SonoVue) and the control group (wild-type P53). Following treatment, a hemocytometer was used to measure cell lysis, reverse transcription-quantitative polymerase chain reaction and western blotting were performed to detect P53 gene transfection efficiency, Cell Counting Kit-8 was employed to reveal cell proliferation and Annexin V/propidium iodide staining was used to determine cell apoptosis. Cell lysis was minimal in each group. Wild-type P53 gene and protein expression were significantly increased in the PC-3 cells in group G compared with the control and all other groups (P<0.01). Cell proliferation was significantly suppressed in group G compared with the control group and all other groups (P<0.01). Cell apoptosis levels in group G were significantly improved compared with the control group and all other groups (P<0.01). Thus, the results of the present study indicate that the use of low-frequency and low-energy ultrasound in combination with SonoVue microbubbles may be a potent physical method for increasing liposome gene delivery efficiency. PMID:27313702

  8. Treatment of Nasopharyngeal Carcinoma Using Intensity-Modulated Radiotherapy-The National Cancer Centre Singapore Experience

    SciTech Connect

    Tham, Ivan Weng-Keong; Hee, Siew Wan; Yeo, Richard Ming-Chert; Salleh, Patemah; Lee, James; Tan, Terence Wee-Kiat; Fong, Kam Weng; Chua, Eu Tiong; Wee, Joseph Tien-Seng

    2009-12-01

    Purpose: The aim of this study was to determine the efficacy and acute toxicity of our early experience with treating nasopharyngeal carcinoma (NPC) patients with intensity-modulated radiotherapy (IMRT). Methods and materials: A review was conducted on case records of 195 patients with histologically proven, nonmetastatic NPC treated with IMRT between 2002 and 2005. MRI of the head and neck was fused with CT simulation images. All plans had target volumes at three dose levels, with a prescribed dose of 70 Gy to the gross disease, in 2.0-2.12 Gy/fraction over 33-35 fractions. Cisplatin-based chemotherapy was offered to Stage III/IV patients. Results: Median patient age was 52 years, and 69% were male. Median follow-up was 36.5 months. One hundred and twenty-three patients had Stage III/IV disease (63%); 50 (26%) had T4 disease. One hundred and eighty-eight (96%) had complete response; 7 (4%) had partial response. Of the complete responders, 10 (5.3%) had local recurrence, giving a 3-year local recurrence-free survival estimate of 93.1% and a 3-year disease-free survival of 82.1%. Fifty-one patients (26%) had at least one Grade 3 toxicity. Conclusions: Results from our series are comparable to those reported by other centers. Acute toxicity is common. Local failure or persistent disease, especially in patients with bulky T4 disease, are issues that must be addressed in future trials.

  9. An Experimental Study of High Intensity Focused Ultrasound on Pig's Pancreas and the Early Clinical Experience on Pancreatic Cancer

    NASA Astrophysics Data System (ADS)

    Xiong, LiuLin; Huang, XiaoBo; Yao, SongSen; Yu, JinSheng; Hwang, JooHa; Fei, XingBo; Yu, QiuHong; Xue, WeiCheng; Zheng, ZhuYing; Wang, XiaoFeng

    2007-05-01

    Objective: To investigate the feasibility and safety of high intensity focused ultrasound (HIFU) treatment of in vivo pig pancreases, and to evaluate the safety and efficacy of HIFU in the clinical treatment of pancreatic cancer in humans. Methods: HIFU was performed in 12 domestic pig pancreases in vivo with varying acoustic energies. The safety of HIFU treatments was assessed by necropsy. The pathology and microstructure of the treated pancreases were evaluated using standard histology and transmission electron microscopy. Following the animal studies 62 patients with advanced pancreas cancer were treated with 250 - 420 W of acoustic power. There were 3 patients with stage II, 23 patients with stage III, and 36 patients with stage IV disease. Results: In animal studies, precise regions of coagulation necrosis were identified on pathology in 8 specimens that were treated with 420 W or 645 W acoustic power. Treatment effects were unable to be identified in 4 specimens treated with 300˜340 W acoustic power; however, damages to the cells microstructure and apoptosis were identified on electron microscopy. Damage to the stomach and colon were seen in some animals treated with 645 W. In the clinical treatments in humans the following were seen: local tumor control: complete response (CR) 0%, partial response (PR) 17.7%, no change (NC) 54.8%, progressive disease (PD) 27.5%. Pain relief was achieved in 87.1% of patients. The median survival for stage II and III patients was 11.2 months and median survival for stage IV patients was 5.6 months. The total median survival was 8.6 months. The survival rate at 1 year was as follows: stage II and III 42.3%, stage IV 5.6%. The survival rate at 2 years was as follows: stage II and III 15.4%, stage IV 0%. There were no severe complications or adverse events related to HIFU therapy seen in any of the patients treated. Conclusions: This study supports the feasibility of HIFU in the treatment of pancreatic cancer. The clinical

  10. Twelve years' experience with high-intensity focused ultrasound (HIFU) using sonablate™ devices for the treatment of localized prostate cancer

    NASA Astrophysics Data System (ADS)

    Uchida, Toyoaki; Nakano, Muyura; Shoji, Sunao; Nagata, Yoshihiro; Usui, Yukio; Terachi, Toshiro

    2012-10-01

    To report on the long-term results of high-intensity focused ultrasound (HIFU) in the treatment of localized prostate cancer. Patients with clinical Stage T1c-T3N0M0, biopsy proven, localized prostate cancer, with a serum prostate specific antigen (PSA) level of <30 ng/ml, any Gleason score were included. All patients underwent HIFU using the Sonablate™ (S) device and were required to have a minimal follow-up of 2 years after the last HIFU session to be included in this analysis. Four different generation HIFU devices, S200, S500, S500 version 4 and S500 TCM, have been used for this study. Biochemical failure was defined according to the Phoenix definition (PSA nadir+2ng/ml). Seven hundred and fifty-three men with prostate cancer were included. The patients were divided into two groups: in the Former group, 421 patients were treated with S200 and 500 from 1990 to 2005; in the Latter group, 332 patients were treated with S500 ver. 4 and TCM from 2005 to 2009. The mean age, PSA, Gleason score, operation time, and follow-up period in the Former and Latter groups were 68 and 67 years, 11.3 and 9.7 ng/ml, 6.2 and 6.6, 167 and 101 min, and 49 and 38 months, respectively. The biochemical disease-free rate (BDFR) in the groups at 5 years was, respectively, 67% and 53%, and was 50% at 10 years in the Former group (p<0.0001). The BDFR in patients in the low-, intermediate-, and high-risk groups in the Former group at 5 and 10 years were 68% and 65%, 52% and 48%, and 43% and 40%, respectively (p<0.0001). The BDFR in patients in the low-, intermediate-, and high-risk groups in the Latter group at 5 years were 83%, 76%, and 42% (p<0.0001). The negative prostate biopsy rate in the Former and Latter groups was 81% and 93%, respectively. Postoperative erectile dysfunction was noted in 45%, 38%, and 24% of patients at 6 months, 12 months, and 2 years after HIFU. The results after long-term follow-up have indicated that HIFU is an efficient and safe treatment for patients with

  11. Is Planned Neck Dissection Necessary for Head and Neck Cancer After Intensity-Modulated Radiotherapy?

    SciTech Connect

    Yao Min |. E-mail: min-yao@uiowa.edu; Hoffman, Henry T.; Funk, Gerry F. |; Chang, Kristi; Smith, Russell B. |; Tan Huaming; Clamon, Gerald H.; Dornfeld, Ken |; Buatti, John M. |

    2007-07-01

    Purpose: The objective of this study was to determine regional control of local regional advanced head and neck squamous cell carcinoma (HNSCC) treated with intensity-modulated radiotherapy (IMRT), along with the role and selection criteria for neck dissection after IMRT. Methods and Materials: A total of 90 patients with stage N2A or greater HNSCC were treated with definitive IMRT from December 1999 to July 2005. Three clinical target volumes were defined and were treated to 70 to 74 Gy, 60 Gy, and 54 Gy, respectively. Neck dissection was performed for selected patients after IMRT. Selection criteria evolved during this period with emphasis on post-IMRT [{sup 18}F] fluorodeoxyglucose positron emission tomography in recent years. Results: Median follow-up for all patients was 29 months (range, 0.2-74 months). All living patients were followed at least 9 months after completing treatment. Thirteen patients underwent neck dissection after IMRT because of residual lymphadenopathy. Of these, 6 contained residual viable tumor. Three patients with persistent adenopathy did not undergo neck dissection: 2 refused and 1 had lung metastasis. Among the remaining 74 patients who were observed without neck dissection, there was only 1 case of regional failure. Among all 90 patients in this study, the 3-year local and regional control was 96.3% and 95.4%, respectively. Conclusions: Appropriately delivered IMRT has excellent dose coverage for cervical lymph nodes. A high radiation dose can be safely delivered to the abnormal lymph nodes. There is a high complete response rate. Routine planned neck dissection for patients with N2A and higher stage after IMRT is not necessary. Post-IMRT [{sup 18}F] fluorodeoxyglucose positron emission tomography is a useful tool in selecting patients appropriate for neck dissection.

  12. Utility of Smart Arc CDR for intensity-modulated radiation therapy for prostate cancer.

    PubMed

    Hatanaka, Shogo; Tamaki, Seiichi; Endo, Haruna; Mizuno, Norifumi; Nakamura, Naoki

    2014-07-01

    Volumetric-modulated arc therapy (VMAT) is a widespread intensity-modulated radiation therapy (IMRT) method, however, VMAT requires adaptation of the radiation treatment planning system (RTPS) and linear accelerator (linac); these upgrades are quite expensive. The Smart Arc of Pinnacle(3) (Philips), which is the software used in VMAT calculations, can select constant dose rate (CDR) mode. This approach has a low initial cost because the linac upgrade is not required. The objective of this study was to clarify the utility of CDR mode for prostate IMRT. Pinnacle(3) and Clinac 21EX linac (Varian, 10 MV X-rays) were used for planning. The plans were created for 28 patients using a fixed multi-field IMRT (f-IMRT), VMAT and CDR techniques. The dose distribution results were classified into three groups: optimal, suboptimal and reject. For the f-IMRT, VMAT and CDR results, 25, 26 and 21 patients were classified as 'optimal', respectively. Our results show a significant reduction in the achievement rate of 'optimal' for a CDR when the bladder volume is <100 cm(3). The total numbers of monitoring units (MUs) (average ± 1σ) were 469 ± 53, 357 ± 35 and 365 ± 33; the average optimization times were ∼50 min, 2 h and 2 h 40 min, and the irradiation times were ∼280 s, 60 s and 110 s, respectively. CDR can reduce the total MUs and irradiation time compared with f-IMRT, and CDR has a lower initial cost compared with VMAT. Thus, for institutions that do not currently perform VMAT, CDR is a useful option. Additionally, in the context of patient identification, bladder volume may be useful.

  13. Automatically-generated rectal dose constraints in intensity-modulated radiation therapy for prostate cancer

    NASA Astrophysics Data System (ADS)

    Hwang, Taejin; Kim, Yong Nam; Kim, Soo Kon; Kang, Sei-Kwon; Cheong, Kwang-Ho; Park, Soah; Yoon, Jai-Woong; Han, Taejin; Kim, Haeyoung; Lee, Meyeon; Kim, Kyoung-Joo; Bae, Hoonsik; Suh, Tae-Suk

    2015-06-01

    The dose constraint during prostate intensity-modulated radiation therapy (IMRT) optimization should be patient-specific for better rectum sparing. The aims of this study are to suggest a novel method for automatically generating a patient-specific dose constraint by using an experience-based dose volume histogram (DVH) of the rectum and to evaluate the potential of such a dose constraint qualitatively. The normal tissue complication probabilities (NTCPs) of the rectum with respect to V %ratio in our study were divided into three groups, where V %ratio was defined as the percent ratio of the rectal volume overlapping the planning target volume (PTV) to the rectal volume: (1) the rectal NTCPs in the previous study (clinical data), (2) those statistically generated by using the standard normal distribution (calculated data), and (3) those generated by combining the calculated data and the clinical data (mixed data). In the calculated data, a random number whose mean value was on the fitted curve described in the clinical data and whose standard deviation was 1% was generated by using the `randn' function in the MATLAB program and was used. For each group, we validated whether the probability density function (PDF) of the rectal NTCP could be automatically generated with the density estimation method by using a Gaussian kernel. The results revealed that the rectal NTCP probability increased in proportion to V %ratio , that the predictive rectal NTCP was patient-specific, and that the starting point of IMRT optimization for the given patient might be different. The PDF of the rectal NTCP was obtained automatically for each group except that the smoothness of the probability distribution increased with increasing number of data and with increasing window width. We showed that during the prostate IMRT optimization, the patient-specific dose constraints could be automatically generated and that our method could reduce the IMRT optimization time as well as maintain the

  14. Intensity-Modulated Radiotherapy in the Treatment of Oropharyngeal Cancer: Clinical Outcomes and Patterns of Failure

    SciTech Connect

    Daly, Megan E.; Le, Quynh-Thu; Maxim, Peter G.; Loo, Billy W.; Kaplan, Michael J.; Fischbein, Nancy J.; Pinto, Harlan; Chang, Daniel T.

    2010-04-15

    Purpose: To report outcomes, failures, and toxicities in patients treated with intensity-modulated radiotherapy (IMRT) for squamous cell carcinoma of the oropharynx. Methods And Materials: Between Aug 2001 and Oct 2007, 107 patients were treated with IMRT with curative intent at Stanford University. Twenty-two patients were treated postoperatively, and 85 were treated definitively. Concurrent platinum-based chemotherapy was administered to 86 patients (80%) and cetuximab to 8 patients (7%). The prescribed dose was 66 Gy at 2.2 Gy/fraction for definitively treated cases and 60 Gy at 2 Gy/fraction for postoperative cases. Median follow-up was 29 months among surviving patients (range, 4-105 months). Results: Eight patients had persistent disease or local-regional failure at a median of 6.5 months (range, 0-9.9 months). Six local failures occurred entirely within the high-risk clinical target volume (CTV) (one with simultaneous distant metastasis). One patient relapsed within the high- and intermediate-risk CTV. One patient had a recurrence at the junction between the IMRT and low-neck fields. Seven patients developed distant metastasis as the first site of failure. The 3-year local-regional control (LRC), freedom from distant metastasis, overall survival, and disease-free survival rates were 92%, 92%, 83%, and 81%, respectively. T stage (T4 vs. T1-T3) was predictive of poorer LRC (p = 0.001), overall survival (p = 0.001), and disease-free survival (p < 0.001) rates. Acute toxicity consisted of 58% grade 3 mucosal and 5% grade 3 skin reactions. Six patients (6%) developed grade >=3 late complications. Conclusions: IMRT provides excellent LRC for oropharyngeal squamous cell carcinoma. Distant metastases are a major failure pattern. No marginal failures were observed.

  15. Dosimetric investigation of breath-hold intensity-modulated radiotherapy for pancreatic cancer

    SciTech Connect

    Nakamura, Mitsuhiro; Kishimoto, Shun; Iwamura, Kohei; Shiinoki, Takehiro; Nakamura, Akira; Matsuo, Yukinori; Shibuya, Keiko; Hiraoka, Masahiro

    2012-01-15

    Purpose: To experimentally investigate the effects of variations in respiratory motion during breath-holding (BH) at end-exhalation (EE) on intensity-modulated radiotherapy (BH-IMRT) dose distribution using a motor-driven base, films, and an ionization chamber. Methods: Measurements were performed on a linear accelerator, which has a 120-leaf independently moving multileaf collimator with 5-mm leaf width at the isocenter for the 20-cm central field. Polystyrene phantoms with dimensions of 40 x 40 x 10 cm were set on a motor-driven base. All gantry angles of seven IMRT plans (a total of 35 fields) were changed to zero, and doses were then delivered to a film placed at a depth of 4 cm and an ionization chamber at a depth of 5 cm in the phantom with a dose rate of 600 MU/min under the following conditions: pulsation from the abdominal aorta and baseline drift with speeds of 0.2 mm/s (BD{sub 0.2mm/s}) and 0.4 mm/s (BD{sub 0.4mm/s}). As a reference for comparison, doses were also delivered to the chamber and film under stationary conditions. Results: In chamber measurements, means {+-} standard deviations of the dose deviations between stationary and moving conditions were -0.52% {+-} 1.03% (range: -3.41-1.05%), -0.07% {+-} 1.21% (range: -1.88-4.31%), and 0.03% {+-} 1.70% (range: -2.70-6.41%) for pulsation, BD{sub 0.2mm/s}, and BD{sub 0.4mm/s}, respectively. The {gamma} passing rate ranged from 99.5% to 100.0%, even with the criterion of 2%/1 mm for pulsation pattern. In the case of BD{sub 0.4mm/s}, the {gamma} passing rate for four of 35 fields (11.4%) did not reach 90% with a criterion of 3%/3 mm. The differences in {gamma} passing rate between BD{sub 0.2mm/s} and BD{sub 0.4mm/s} were statistically significant for each criterion. Taking {gamma} passing rates of > 90% as acceptable with a criterion of 3%/3 mm, large differences were observed in the {gamma} passing rate between the baseline drift of {<=}5 mm and that of >5 mm (minimum {gamma} passing rate: 92.0% vs 82

  16. Increased chromosome aberration frequencies in the Bowen's patients compared to non-cancerous skin lesions individuals exposed to arsenic.

    PubMed

    Ghosh, Pritha; Banerjee, Mayukh; De Chaudhuri, Sujata; Das, Jayanta K; Sarma, Nilendu; Basu, Arindam; Giri, Ashok K

    2007-08-15

    Cytogenetic biomarkers are essential for assessing environmental exposure that can predict adverse human health effects such as cellular damage. Chromosomal aberrations are the most important cytogenetic end-points successfully used for the cancer risk assessment of populations occupationally or environmentally exposed to different toxic chemicals. Previous reports suggest that, increased frequency of chromosomal aberration (CA), in peripheral blood lymphocytes, is a predictor of cancer. Arsenic is a paradoxical human carcinogen, clastogen and aneugen. Despite of exposure at similar extent, only 15-20% of individuals show arsenic induced skin lesions including Bowen's disease (BD). Previously we have reported the significant increase in CA in the individuals with arsenic induced skin lesions when compared to individuals without any skin lesions, drinking arsenic contaminated water at similar extent. Presently, a matched case-control study was performed to examine whether biomarkers such as chromosomal aberrations can predict the development of arsenic induced Bowen's (in situ carcinoma) diseases. Chromosomal aberrations (both chromosome and chromatid types) and mitotic index were analyzed from the lymphocytes of 25 cases of Bowen's patient which was compared to matched control from the individuals with arsenic induced non-cancerous skin lesions such as raindrop pigmentation, keratosis of palm and sole, hypo and hyper pigmentation. Chromosomal aberrations/cell, chromosome type aberrations and total percentage of aberrant cells were significantly higher in cases compared to control (p<0.01). These results suggest that chromosomal aberrations can be used for cancer risk assessment of the population exposed to arsenic through drinking water.

  17. Determining the frequency of pathogenic germline variants from exome sequencing in patients with castrate-resistant prostate cancer

    PubMed Central

    Hart, Steven N; Ellingson, Marissa S; Schahl, Kim; Vedell, Peter T; Carlson, Rachel E; Sinnwell, Jason P; Barman, Poulami; Sicotte, Hugues; Eckel-Passow, Jeanette E; Wang, Liguo; Kalari, Krishna R; Qin, Rui; Kruisselbrink, Teresa M; Jimenez, Rafael E; Bryce, Alan H; Tan, Winston; Weinshilboum, Richard; Wang, Liewei; Kohli, Manish

    2016-01-01

    Objectives To determine the frequency of pathogenic inherited mutations in 157 select genes from patients with metastatic castrate-resistant prostate cancer (mCRPC). Design Observational. Setting Multisite US-based cohort. Participants Seventy-one adult male patients with histological confirmation of prostate cancer, and had progressive disease while on androgen deprivation therapy. Results Twelve patients (17.4%) showed evidence of carrying pathogenic or likely pathogenic germline variants in the ATM, ATR, BRCA2, FANCL, MSR1, MUTYH, RB1, TSHR and WRN genes. All but one patient opted in to receive clinically actionable results at the time of study initiation. We also found that pathogenic germline BRCA2 variants appear to be enriched in mCRPC compared to familial prostate cancers. Conclusions Pathogenic variants in cancer-susceptibility genes are frequently observed in patients with mCRPC. A substantial proportion of patients with mCRPC or their family members would derive clinical utility from mutation screening. Trial registration number NCT01953640; Results. PMID:27084275

  18. Dosimetric evaluation of planning target volume margin reduction for prostate cancer via image-guided intensity-modulated radiation therapy

    NASA Astrophysics Data System (ADS)

    Hwang, Taejin; Kang, Sei-Kwon; Cheong, Kwang-Ho; Park, Soah; Yoon, Jai-Woong; Han, Taejin; Kim, Haeyoung; Lee, Meyeon; Kim, Kyoung-Joo; Bae, Hoonsik; Suh, Tae-Suk

    2015-07-01

    The aim of this study was to quantitatively estimate the dosimetric benefits of the image-guided radiation therapy (IGRT) system for the prostate intensity-modulated radiation therapy (IMRT) delivery. The cases of eleven patients who underwent IMRT for prostate cancer without a prostatectomy at our institution between October 2012 and April 2014 were retrospectively analyzed. For every patient, clinical target volume (CTV) to planning target volume (PTV) margins were uniformly used: 3 mm, 5 mm, 7 mm, 10 mm, 12 mm, and 15 mm. For each margin size, the IMRT plans were independently optimized by one medical physicist using Pinnalce3 (ver. 8.0.d, Philips Medical System, Madison, WI) in order to maintain the plan quality. The maximum geometrical margin (MGM) for every CT image set, defined as the smallest margin encompassing the rectum at least at one slice, was between 13 mm and 26 mm. The percentage rectum overlapping PTV (%V ROV ), the rectal normal tissue complication probability (NTCP) and the mean rectal dose (%RD mean ) increased in proportion to the increase of PTV margin. However the bladder NTCP remained around zero to some extent regardless of the increase of PTV margin while the percentage bladder overlapping PTV (%V BOV ) and the mean bladder dose (%BD mean ) increased in proportion to the increase of PTV margin. Without relatively large rectum or small bladder, the increase observed for rectal NTCP, %RDmean and %BD mean per 1-mm PTV margin size were 1.84%, 2.44% and 2.90%, respectively. Unlike the behavior of the rectum or the bladder, the maximum dose on each femoral head had little effect on PTV margin. This quantitative study of the PTV margin reduction supported that IG-IMRT has enhanced the clinical effects over prostate cancer with the reduction of normal organ complications under the similar level of PTV control.

  19. Quality of Life After Hypofractionated Concomitant Intensity-Modulated Radiotherapy Boost for High-Risk Prostate Cancer

    SciTech Connect

    Quon, Harvey; Cheung, Patrick C.F.; Loblaw, D. Andrew; Morton, Gerard; Pang, Geordi; Szumacher, Ewa; Danjoux, Cyril; Choo, Richard; Kiss, Alex; Mamedov, Alexandre; Deabreu, Andrea

    2012-06-01

    Purpose: To evaluate the change in health-related quality of life (QOL) of patients with high-risk prostate cancer treated using hypofractionated radiotherapy combined with long-term androgen deprivation therapy. Methods and Materials: A prospective Phase I-II study enrolled patients with any of the following: clinical Stage T3 disease, prostate-specific antigen level {>=}20 ng/mL, or Gleason score 8-10. Radiotherapy consisted of 45 Gy (1.8 Gy per fraction) to the pelvic lymph nodes with a concomitant 22.5 Gy intensity-modulated radiotherapy boost to the prostate, for a total of 67.5 Gy (2.7 Gy per fraction) in 25 fractions over 5 weeks. Daily image guidance was performed using three gold seed fiducials. Quality of life was measured using the Expanded Prostate Cancer Index Composite (EPIC), a validated tool that assesses four primary domains (urinary, bowel, sexual, and hormonal). Results: From 2004 to 2007, 97 patients were treated. Median follow-up was 39 months. Compared with baseline, at 24 months there was no statistically significant change in the mean urinary domain score (p = 0.99), whereas there were decreases in the bowel (p < 0.01), sexual (p < 0.01), and hormonal (p < 0.01) domains. The proportion of patients reporting a clinically significant difference in EPIC urinary, bowel, sexual, and hormonal scores at 24 months was 27%, 31%, 55%, and 60%, respectively. However, moderate and severe distress related to these symptoms was minimal, with increases of only 3% and 5% in the urinary and bowel domains, respectively. Conclusions: Hypofractionated radiotherapy combined with long-term androgen deprivation therapy was well tolerated. Although there were modest rates of clinically significant patient-reported urinary and bowel toxicity, most of this caused only mild distress, and moderate and severe effects on QOL were limited. Additional follow-up is ongoing to characterize long-term QOL.

  20. Cost-Effectiveness Analysis of Intensity Modulated Radiation Therapy Versus 3-Dimensional Conformal Radiation Therapy for Anal Cancer

    SciTech Connect

    Hodges, Joseph C.; Beg, Muhammad S.; Das, Prajnan; Meyer, Jeffrey

    2014-07-15

    Purpose: To compare the cost-effectiveness of intensity modulated radiation therapy (IMRT) and 3-dimensional conformal radiation therapy (3D-CRT) for anal cancer and determine disease, patient, and treatment parameters that influence the result. Methods and Materials: A Markov decision model was designed with the various disease states for the base case of a 65-year-old patient with anal cancer treated with either IMRT or 3D-CRT and concurrent chemotherapy. Health states accounting for rates of local failure, colostomy failure, treatment breaks, patient prognosis, acute and late toxicities, and the utility of toxicities were informed by existing literature and analyzed with deterministic and probabilistic sensitivity analysis. Results: In the base case, mean costs and quality-adjusted life expectancy in years (QALY) for IMRT and 3D-CRT were $32,291 (4.81) and $28,444 (4.78), respectively, resulting in an incremental cost-effectiveness ratio of $128,233/QALY for IMRT compared with 3D-CRT. Probabilistic sensitivity analysis found that IMRT was cost-effective in 22%, 47%, and 65% of iterations at willingness-to-pay thresholds of $50,000, $100,000, and $150,000 per QALY, respectively. Conclusions: In our base model, IMRT was a cost-ineffective strategy despite the reduced acute treatment toxicities and their associated costs of management. The model outcome was sensitive to variations in local and colostomy failure rates, as well as patient-reported utilities relating to acute toxicities.

  1. Early Clinical Outcome With Concurrent Chemotherapy and Extended-Field, Intensity-Modulated Radiotherapy for Cervical Cancer

    SciTech Connect

    Beriwal, Sushil . E-mail: beriwals@upmc.edu; Gan, Gregory N.; Heron, Dwight E.; Selvaraj, Raj N.; Kim, Hayeon; Lalonde, Ron; Kelley, Joseph L.; Edwards, Robert P.

    2007-05-01

    Purpose: To assess the early clinical outcomes with concurrent cisplatin and extended-field intensity-modulated radiotherapy (EF-IMRT) for carcinoma of the cervix. Methods and Materials: Thirty-six patients with Stage IB2-IVA cervical cancer treated with EF-IMRT were evaluated. The pelvic lymph nodes were involved in 19 patients, and of these 19 patients, 10 also had para-aortic nodal disease. The treatment volume included the cervix, uterus, parametria, presacral space, upper vagina, and pelvic, common iliac, and para-aortic nodes to the superior border of L1. Patients were assessed for acute toxicities according to the National Cancer Institute Common Toxicity Criteria for Adverse Events, version 3.0. All late toxicities were scored with the Radiation Therapy Oncology Group late toxicity score. Results: All patients completed the prescribed course of EF-IMRT. All but 2 patients received brachytherapy. Median length of treatment was 53 days. The median follow-up was 18 months. Acute Grade {>=}3 gastrointestinal, genitourinary, and myelotoxicity were seen in 1, 1, and 10 patients, respectively. Thirty-four patients had complete response to treatment. Of these 34 patients, 11 developed recurrences. The first site of recurrence was in-field in 2 patients (pelvis in 1, pelvis and para-aortic in 1) and distant in 9 patients. The 2-year actuarial locoregional control, disease-free survival, overall survival, and Grade {>=}3 toxicity rates for the entire cohort were 80%, 51%, 65%, and 10%, respectively. Conclusion: Extended-field IMRT with concurrent chemotherapy was tolerated well, with acceptable acute and early late toxicities. The locoregional control rate was good, with distant metastases being the predominant mode of failure. We are continuing to accrue a larger number of patients and longer follow-up data to further extend our initial observations with this approach.

  2. Parotid Gland Dose in Intensity-Modulated Radiotherapy for Head and Neck Cancer: Is What You Plan What You Get?

    SciTech Connect

    O'Daniel, Jennifer C.; Garden, Adam S.; Schwartz, David L.; Wang He; Ang, Kian K.; Ahamad, Anesa; Rosenthal, David I.; Morrison, William H.; Asper, Joshua A.; Zhang Lifei; Tung Shihming; Mohan, Radhe; Dong Lei

    2007-11-15

    Purpose: To quantify the differences between planned and delivered parotid gland and target doses, and to assess the benefits of daily bone alignment for head and neck cancer patients treated with intensity-modulated radiotherapy (IMRT). Methods and Materials: Eleven head and neck cancer patients received two CT scans per week with an in-room CT scanner over the course of their radiotherapy. The clinical IMRT plans, designed with 3-mm to 4-mm planning margins, were recalculated on the repeat CT images. The plans were aligned using the actual treatment isocenter marked with radiopaque markers (BB) and bone alignment to the cervical vertebrae to simulate image-guided setup. In-house deformable image registration software was used to map daily dose distributions to the original treatment plan and to calculate a cumulative delivered dose distribution for each patient. Results: Using conventional BB alignment led to increases in the parotid gland mean dose above the planned dose by 5 to 7 Gy in 45% of the patients (median, 3.0 Gy ipsilateral, p = 0.026; median, 1.0 Gy contralateral, p = 0.016). Use of bone alignment led to reductions relative to BB alignment in 91% of patients (median, 2 Gy; range, 0.3-8.3 Gy; 15 of 22 parotids improved). However, the parotid dose from bone alignment was still greater than planned (median, 1.0 Gy, p = 0.007). Neither approach affected tumor dose coverage. Conclusions: With conventional BB alignment, the parotid gland mean dose was significantly increased above the planned mean dose. Using daily bone alignment reduced the parotid dose compared with BB alignment in almost all patients. A 3- to 4-mm planning margin was adequate for tumor dose coverage.

  3. Dosimetric Comparison of Bone Marrow-Sparing Intensity-Modulated Radiotherapy Versus Conventional Techniques for Treatment of Cervical Cancer

    SciTech Connect

    Mell, Loren K.; Tiryaki, Hanifi; Ahn, Kang-Hyun; Mundt, Arno J.; Roeske, John C.; Aydogan, Bulent

    2008-08-01

    Purpose: To compare bone marrow-sparing intensity-modulated pelvic radiotherapy (BMS-IMRT) with conventional (four-field box and anteroposterior-posteroanterior [AP-PA]) techniques in the treatment of cervical cancer. Methods and Materials: The data from 7 cervical cancer patients treated with concurrent chemotherapy and IMRT without BMS were analyzed and compared with data using four-field box and AP-PA techniques. All plans were normalized to cover the planning target volume with the 99% isodose line. The clinical target volume consisted of the pelvic and presacral lymph nodes, uterus and cervix, upper vagina, and parametrial tissue. Normal tissues included bowel, bladder, and pelvic bone marrow (PBM), which comprised the lumbosacral spine and ilium and the ischium, pubis, and proximal femora (lower pelvis bone marrow). Dose-volume histograms for the planning target volume and normal tissues were compared for BMS-IMRT vs. four-field box and AP-PA plans. Results: BMS-IMRT was superior to the four-field box technique in reducing the dose to the PBM, small bowel, rectum, and bladder. Compared with AP-PA plans, BMS-IMRT reduced the PBM volume receiving a dose >16.4 Gy. BMS-IMRT reduced the volume of ilium, lower pelvis bone marrow, and bowel receiving a dose >27.7, >18.7, and >21.1 Gy, respectively, but increased dose below these thresholds compared with the AP-PA plans. BMS-IMRT reduced the volume of lumbosacral spine bone marrow, rectum, small bowel, and bladder at all dose levels in all 7 patients. Conclusion: BMS-IMRT reduced irradiation of PBM compared with the four-field box technique. Compared with the AP-PA technique, BMS-IMRT reduced lumbosacral spine bone marrow irradiation and reduced the volume of PBM irradiated to high doses. Therefore BMS-IMRT might reduce acute hematologic toxicity compared with conventional techniques.

  4. Adaptive Planning in Intensity-Modulated Radiation Therapy for Head and Neck Cancers: Single-Institution Experience and Clinical Implications

    SciTech Connect

    Ahn, Peter H.; Chen, Chin-Cheng; Ahn, Andrew I.; Hong, Linda; Scripes, Paola G.; Shen Jin; Lee, Chen-Chiao; Miller, Eken