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

    PubMed

    Yang, Y U; Bai, Wenkun; Chen, Yini; Lin, Yanduan; Hu, Bing

    2015-11-01

    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/cm(2); 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.

  5. Cancer cell proliferation is inhibited by specific modulation frequencies

    PubMed Central

    Zimmerman, J W; Pennison, M J; Brezovich, I; Yi, N; Yang, C T; Ramaker, R; Absher, D; Myers, R M; Kuster, N; Costa, F P; Barbault, A; Pasche, B

    2012-01-01

    Background: There is clinical evidence that very low and safe levels of amplitude-modulated electromagnetic fields administered via an intrabuccal spoon-shaped probe may elicit therapeutic responses in patients with cancer. However, there is no known mechanism explaining the anti-proliferative effect of very low intensity electromagnetic fields. Methods: To understand the mechanism of this novel approach, hepatocellular carcinoma (HCC) cells were exposed to 27.12 MHz radiofrequency electromagnetic fields using in vitro exposure systems designed to replicate in vivo conditions. Cancer cells were exposed to tumour-specific modulation frequencies, previously identified by biofeedback methods in patients with a diagnosis of cancer. Control modulation frequencies consisted of randomly chosen modulation frequencies within the same 100 Hz–21 kHz range as cancer-specific frequencies. Results: The growth of HCC and breast cancer cells was significantly decreased by HCC-specific and breast cancer-specific modulation frequencies, respectively. However, the same frequencies did not affect proliferation of nonmalignant hepatocytes or breast epithelial cells. Inhibition of HCC cell proliferation was associated with downregulation of XCL2 and PLP2. Furthermore, HCC-specific modulation frequencies disrupted the mitotic spindle. Conclusion: These findings uncover a novel mechanism controlling the growth of cancer cells at specific modulation frequencies without affecting normal tissues, which may have broad implications in oncology. PMID:22134506

  6. 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.

  7. Intensity and fundamental frequency control in tracheoesophageal voice

    PubMed Central

    Schindler, A; Canale, A; Cavalot, AL; Albera, R; Capaccio, P; Ottaviani, F; Schindler, O

    2005-01-01

    Summary Tracheo-oesophageal voice prostheses are currently widely used following total laryngectomy. Data on maximum phonation time and spectrum have been studied by various Authors and are well known. On the contrary, intensity and fundamental frequency control have received little attention. Intensity and fundamental frequency play an important role in the prosodic aspects of speech. Fundamental frequency variations have been studied in tone language speakers, but the ability to voluntarily change intensity and fundamental frequency remain to be fully investigated. Aim of the present study was to analyse the ability of tracheo-oesophageal voice users to change intensity and fundamental frequency. A total of 12 male subjects who underwent total laryngectomy, in whom a tracheo-oesophageal prosthesis had been inserted, were considered. Maximum phonation time was calculated. Each subject was asked to utter an /a/ as loud as possible and an /a/ as soft as possible. Each subject was then asked to utter an /a/ at comfortable pitch and then at an interval of a fifth. Intensity as well as fundamental frequency variations were compared using Wilcoxon signed rank test. Correlation between maximum phonation time and variation in intensity and in fundamental frequency as well as between the two latter variables was calculated using Spearman’s rank correlation coefficient. Mean maximum phonation time was 8 (± 3.8) sec. Mean energy was 50 (± 4.8) dB SPL for soft phonation and 68 (± 4.7) dB SPL for loud phonation. The difference observed was statistically significant (p < 0.02). Mean fundamental frequency values were 106 (± 14) Hz and 135 (± 34) Hz at the interval of a fifth. The difference observed was statistically significant (p < 0.02). Tracheo-oesophageal voice users were able to change intensity and fundamental frequency, but their control was rather poor. Variations in intensity, as well as fundamental frequency, did not show any correlation with maximum phonation

  8. 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.

  9. Intensity and frequency: dimensions underlying positive and negative affect.

    PubMed

    Diener, E; Larsen, R J; Levine, S; Emmons, R A

    1985-05-01

    Research on emotions and several happiness scales suggest that positive and negative affect are strongly inversely correlated. However, work on subjective well-being indicates that over time, positive and negative affect are independent across persons. In order to reconcile this inconsistency, two dimensions are proposed for personal affective structure: the frequency of positive versus negative affect and the intensity of affect. Subjects in three studies completed daily and momentary reports on their moods. In support of the intensity dimension, the correlations between positive and negative intensity were strong and positive in all three studies. The intensities of specific emotions across persons were also highly correlated. Across the three studies the frequency and intensity of affect varied independently. Although average levels of positive and negative affect showed low correlations, this relation became strongly inverse when intensity was partialed out. Thus the intensity dimension helps explain the relative independence of positive and negative affect. In addition, emotional intensity is offered as a new personality dimension that manifests interesting characteristics.

  10. Bayesian estimation of rainfall intensity-duration-frequency relationships

    NASA Astrophysics Data System (ADS)

    Van de Vyver, H.

    2015-10-01

    Rainfall intensity-duration-frequency (IDF) curves are one of the most commonly used tools in water resources engineering. They give an idea of how return levels of extreme rainfall intensities vary with duration over a range of return periods. It is assumed that the annual maximum intensity follows the generalised extreme value (GEV) distribution. Conventional methods of estimating IDF relationships do not provide estimates of uncertainty. We propose a Bayesian framework for handling uncertainties in IDF models. Firstly, we collect annual maximum intensity data over a relevant range of rainfall durations. Secondly, we define an approximate likelihood, the ;independence; likelihood, in which the correlations have been ignored between maximum intensity data of different durations. Finally, we apply Bayesian inference to obtain the adjusted posterior, which accounts for likelihood misspecification. A comparison with earlier methods, without any adjustment amongst others, shows that the adjusted posteriors are considerably wider.

  11. Radio Frequency Ablation for Primary Liver Cancer

    PubMed Central

    2004-01-01

    Executive Summary Objective The Medical Advisory Secretariat undertook a review of the evidence on the safety, clinical effectiveness, and cost-effectiveness of radio frequency ablation (RFA) compared with other treatments for unresectable hepatocellular carcinoma (HCC) in Ontario. Background Liver cancer is the fifth most common type of cancer globally, although it is most prevalent in Asia and Africa. The incidence of liver cancer has been increasing in the Western world, primarily because of an increased prevalence of hepatitis B and C. Data from Cancer Care Ontario from 1998 to 2002 suggest that the age-adjusted incidence of liver cancer in men rose slightly from 4.5 cases to 5.4 cases per 100,000 men. For women, the rates declined slightly, from 1.8 cases to 1.4 cases per 100,000 women during the same period. Most people who present with symptoms of liver cancer have a progressive form of the disease. The rates of survival in untreated patients in the early stage of the disease range from 50% to 82% at 1 year and 26% to 32% at 2 years. Patients with more advanced stages have survival rates ranging from 0% to 36% at 3 years. Surgical resection and transplantation are the procedures that have the best prognoses; however, only 15% to 20% of patients presenting with liver cancer are eligible for surgery. Resection is associated with a 50% survival rate at 5 years. The Technology: Radio Frequency Ablation RFA is a relatively new technique for the treatment of small liver cancers that cannot be treated with surgery. This technique applies alternating high-frequency electrical currents to the cancerous tissue. The intense heat leads to thermal coagulation that can kill the tumour. RFA is done under general or local anesthesia and can be done percutaneously (through the skin with a small needle), laparoscopically (microinvasively, using a small video camera), or intraoperatively. Percutaneous RFA is usually a day procedure. Methods The leading international

  12. 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.

  13. Hazard from intense low-frequency acoustic impulses. Final report

    SciTech Connect

    Price, G.R.

    1986-10-01

    It was predicted that because the ear is spectrally tuned, it should be most affected by intense impulses with spectral peaks near the frequency where it is tuned best (3.0 kHz for the human ear) and progressively less affected by impulses at lower frequencies. This prediction is counter to all the DRCs for impulse noise; therefore, an adequate test is essential. In order to augment the data on hearing loss to low-spectral-frequency impulses, three groups of cats (eight, nine, and ten animals) were exposed on one occasion to 50 impulses from a 105-mm howitzer at peak SPLs of 153, 159, and 166 dB. Threshold shifts were measured electrophysiologically on the day of exposure (CTS) and following a 2-month recovery period (PTS). Maximum PTSs appeared at 4 kHz (even though the spectral peak of the impulse had been at about 100 Hz), and CTSs recovered into PTSs about half as large. Furthermore, the group data, even small CTSs tended to have a permanent component. These data raise the question as to whether or not any threshold shift persisting an hour or two after exposure to high levels should be considered tolerable. When compared with data from rifle fire exposures, the data confirmed the earlier prediction that as the spectral frequency drops, hazard declines at the rate of a little more than 3 dB/oct, contrary to the rating by existing DRCs.

  14. Pain in Persons With Postpolio Syndrome: Frequency, Intensity, and Impact

    PubMed Central

    Stoelb, Brenda L.; Carter, Gregory T.; Abresch, Richard T.; Purekal, Sophia; McDonald, Craig M.; Jensen, Mark P.

    2008-01-01

    Objective To describe the frequency, intensity, and impact of pain in persons with postpoliomyelitis syndrome (PPS). Design Retrospective, cross-sectional survey. Setting Community-based survey. Participants Convenience sample of people with PPS. Interventions Not applicable. Main Outcome Measures Overall intensity and duration of pain, pain sites, pain interference, pain treatments, and relief provided by pain treatments. Results A total of 91% (n=57) of the study participants (N=63) reported pain. The most frequently reported pain sites were the shoulders, lower back, legs, and hips. Participants reported pain intensity to be the greatest in the knees, legs, wrists, lower back, and head. Pain interfered most with sleep and with activities requiring a high level of musculoskeletal involvement. Respondents also reported pain problems that were more severe than those of the general population and than those of a sample of people with multiple sclerosis. Many treatments had been tried previously for pain, but continued use of treatments was reported by relatively few participants at the time of the survey. Conclusions The findings indicate that pain is a persistent and common problem in persons with PPS, highlighting the need for effective and accessible pain treatments for this population. PMID:18929021

  15. 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

  16. Hazard from intense low-frequency acoustic impulses.

    PubMed

    Price, G R

    1986-10-01

    It was predicted that because the ear is spectrally tuned, it should be most affected by intense impulses with spectral peaks near the frequency where it is tuned best (3.0 kHz for the human ear) and progressively less affected by impulses at lower frequencies [G.R. Price, Scand. Audiol. Suppl. 16, 111-121 (1982)]. This prediction is counter to all the DRCs for impulse noise; therefore an adequate test is essential. In order to augment the data on hearing loss to low-spectral-frequency impulses, three groups of cats (eight, nine, and ten animals) were exposed on one occasion to 50 impulses from a 105-mm howitzer at peak SPLs of 153, 159, and 166 dB. Threshold shifts were measured electrophysiologically on the day of exposure (CTS) and following a 2-month recovery period (PTS). Maximum PTSs appeared at 4 kHz (even though the spectral peak of the impulse had been at about 100 Hz), and CTSs recovered into PTSs about half as large. Furthermore, for group data, even small CTSs tended to have a permanent component. These data raise the question as to whether or not any threshold shift persisting an hour or two after exposure to high levels should be considered tolerable. When compared with data from rifle fire exposures, the data confirmed the earlier prediction that as the spectral frequency drops, hazard declines at the rate of a little more than 3 dB/oct, contrary to the rating by existing DRCs.

  17. Aftereffects of Intense Low-Frequency Sound on Spontaneous Otoacoustic Emissions: Effect of Frequency and Level.

    PubMed

    Jeanson, Lena; Wiegrebe, Lutz; Gürkov, Robert; Krause, Eike; Drexl, Markus

    2017-02-01

    The presentation of intense, low-frequency (LF) sound to the human ear can cause very slow, sinusoidal oscillations of cochlear sensitivity after LF sound offset, coined the "Bounce" phenomenon. Changes in level and frequency of spontaneous otoacoustic emissions (SOAEs) are a sensitive measure of the Bounce. Here, we investigated the effect of LF sound level and frequency on the Bounce. Specifically, the level of SOAEs was tracked for minutes before and after a 90-s LF sound exposure. Trials were carried out with several LF sound levels (93 to 108 dB SPL corresponding to 47 to 75 phons at a fixed frequency of 30 Hz) and different LF sound frequencies (30, 60, 120, 240 and 480 Hz at a fixed loudness level of 80 phons). At an LF sound frequency of 30 Hz, a minimal sound level of 102 dB SPL (64 phons) was sufficient to elicit a significant Bounce. In some subjects, however, 93 dB SPL (47 phons), the lowest level used, was sufficient to elicit the Bounce phenomenon and actual thresholds could have been even lower. Measurements with different LF sound frequencies showed a mild reduction of the Bounce phenomenon with increasing LF sound frequency. This indicates that the strength of the Bounce not only is a simple function of the spectral separation between SOAE and LF sound frequency but also depends on absolute LF sound frequency, possibly related to the magnitude of the AC component of the outer hair cell receptor potential.

  18. Calculation of externally applied electric field intensity for disruption of cancer cell proliferation.

    PubMed

    Sardari, Dariush; Verga, Nicolae

    2010-06-01

    It is already known that electrostatic, magnetostatic, extremely low-frequency electric fields, and pulsed electric field could be utilized in cancer treatment. The healing effect depends on frequency and amplitude of electric field. In the present work, a simple theoretical model is developed to estimate the intensity of electrostatic field that damages a living cell during division. By this model, it is shown that magnification of electric field in the bottleneck of dividing cell is enough to break chemical bounds between molecules by an avalanche process. Our model shows that the externally applied electric field of 4 V/cm intensity is able to hurt a cancer cell at the dividing stage.

  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. Frequency and intensity noise in an injection-locked, solid-state laser

    NASA Astrophysics Data System (ADS)

    Farinas, Alejandro D.; Gustafson, Eric K.; Byer, Robert L.

    1995-02-01

    We have calculated transfer functions for frequency and intensity fluctuations in an injection-locked solid-state laser. At modulation frequencies well below the locking frequency we find significant frequency-noise reduction, and at modulation frequencies above the locking frequency we find that the frequency noise is that of the free-running slave laser. Our intensity-noise theory predicts substantial damping of relaxation oscillations in the slave laser. To verify these results we have measured the frequency and intensity noise of a 5-W, injection-locked Nd:YAG laser.

  1. Analysis of cancer patients admitted to intensive care unit

    PubMed Central

    Aksoy, Yakup; Kaydu, Ayhan; Sahin, Omer Fatih; Kacar, Cem Kivilcim

    2016-01-01

    OBJECTIVE: The present study is an analysis of cancer patients who received follow-up treatment for either cancer-related complications or treatment-associated side effects while hospitalized in the intensive care unit (ICU). METHODS: Records of cancer patients treated at Dr. Lütfi Kırdar Kartal Training and Research Hospital ICU between January 1, 2011 and December 31, 2012 were retrospectively reviewed. Demographic data and type of cancer were recorded in prepared forms and subsequently analyzed. RESULTS: Among 2240 ICU patients treated and hospitalized between January 1, 2011 and December 31, 2012, 482 cancer patients were identified and included in the study. Percentage of cancer patients in ICU was 23.9%. Male to female ratio was determined to be 1.55. First 3 most common cancers found were colorectal (19.7%), lung (15.7%), and stomach cancers (11.6%). Mortality rate of cancer patients hospitalized in ICU was 46.6%. Larynx, lung, urinary bladder, skin, rectosigmoid, hematological, and kidney cancer were more prevalent in male patients, whereas esophageal cancer was seen in more female patients than male patients. Incidence of stomach, brain, and pancreatic cancers, as well as unclassified tumors, was found to be unrelated to gender. CONCLUSION: Rectosigmoid cancer was most common type of cancer observed in our ICU. Esophageal cancer was observed in more females than males, while larynx cancer was more frequently present in males. PMID:28275754

  2. Using spiral intensity profile to quantify head and neck cancer

    PubMed Central

    Kong, Koon Y.; Shanna, Yachna; Raza, S. Hussain; Chen, Zhuo (Georgia); Muller, Susan; Wang, May D.

    2016-01-01

    During the analysis of microscopy images, researchers locate regions of interest (ROI) and extract relevant information within it. Identifying the ROI is mostly done manually and subjectively by pathologists. Computer algorithms could help in reducing their workload and improve reproducibility. In particular, we want to assess the validity of the folic acid receptor as a biomarker for head and neck cancer. We are only interested in folic acid receptors appearing in cancerous tissue. Therefore, the first step is to segment images into cancerous and noncancerous regions. We propose to use a spiral intensity profile for segmentation of light microscopy images. Many algorithms identify objects in an image by considering pixel intensity and spatial information separately. Our algorithm integrates intensity and spatial information by considering the change, or profile, of pixel intensity in a spiral fashion. Using a spiral intensity profile can also perform segmentation at different scales from cancer regions to nuclei cluster to individual nuclei. We compared our algorithm with manually segmented image and obtained a specificity of 83.7% and sensitivity of 61.1%. Spiral intensity profiles can be used as a feature to improve other segmentation algorithms. Segmentation of cancerous images at different scales allows effective quantification of folic acid receptor inside cancerous regions, nuclei clusters, or individual cells.

  3. 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

  4. Single-frequency CW Ti:sapphire laser with intensity noise manipulation and continuous frequency-tuning.

    PubMed

    Jin, Pixian; Lu, Huadong; Wei, Yixiao; Su, Jing; Peng, Kunchi

    2017-01-01

    We present a tunable single-frequency CW Ti:sapphire laser with intensity noise manipulation. The manipulation of the laser intensity noise is realized by varying the frequency of the modulation signal loaded on the electrodes of an intracavity electro-optic etalon. A lithium niobate (LiNbO3) crystal is used to act as the electro-optic etalon, and its electro-optic effect is utilized to modulate the intracavity laser intensity for locking itself to the oscillating wavelength of the laser to implement continuous frequency-tuning. When the electro-optic etalon is locked to the oscillating mode of the Ti:sapphire laser with arbitrarily selected modulation frequency, the maximal continuous frequency-tuning range can reach to 20 GHz, and the laser intensity noise is successfully manipulated simultaneously.

  5. Anti-inflammatory effects of low-intensity extremely high-frequency electromagnetic radiation: frequency and power dependence.

    PubMed

    Gapeyev, A B; Mikhailik, E N; Chemeris, N K

    2008-04-01

    Using a model of acute zymosan-induced footpad edema in NMRI mice, the frequency and power dependence of anti-inflammatory effect of low-intensity extremely high-frequency electromagnetic radiation (EHF EMR) was found. Single whole-body exposure of animals to EHF EMR at the intensity of 0.1 mW/cm(2) for 20 min at 1 h after zymosan injection reduced both the footpad edema and local hyperthermia on average by 20% at the frequencies of 42.2, 51.8, and 65 GHz. Some other frequencies from the frequency range of 37.5-70 GHz were less effective or not effective at all. At fixed frequency of 42.2 GHz and intensity of 0.1 mW/cm(2), the effect had bell-shaped dependence on exposure duration with a maximum at 20-40 min. Reduction of intensity to 0.01 mW/cm(2) resulted in a change of the effect dependence on exposure duration to a linear one. Combined action of cyclooxygenase inhibitor sodium diclofenac and EHF EMR exposure caused a partial additive effect of decrease in footpad edema. Combined action of antihistamine clemastine and EHF EMR exposure caused a dose-dependent abolishment of the anti-inflammatory effect of EHF EMR. The results obtained suggest that arachidonic acid metabolites and histamine are involved in realization of anti-inflammatory effects of low-intensity EHF EMR.

  6. 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

  7. 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.

  8. Bidirectional Shifting Effects of the Sound Intensity on the Best Frequency in the Rat Auditory Cortex

    PubMed Central

    Tao, Can; Zhang, Guangwei; Zhou, Chang; Wang, Lijuan; Yan, Sumei; Zhou, Yi; Xiong, Ying

    2017-01-01

    Frequency and intensity are two independent attributes of sound stimuli. Psychoacoustic studies have found that the sound intensity can affect the perception of frequency; however, the underlying neuronal mechanism remains largely unknown. To investigate if and how the sound level affects the frequency coding for auditory cortical neurons, we recorded the activities of neuronal ensembles and single neurons, as well as the synaptic input evoked by pure tones of different frequency and intensity combinations, in layer 4 of the rat primary auditory cortex. We found that the best frequency (BF) shifted bidirectionally with the increases in intensity. Specifically, the BF of neurons with a low characteristic frequency (CF) shifted lower, whereas the BF of neurons with a higher CF shifted higher. Meanwhile, we found that these shifts in the BF can lead to the expansion of high- and low-frequency areas in the tonotopic map, increasing the evenness of the BF distribution at high intensities. Our results revealed that the frequency tuning can bidirectionally shift with an increase in the sound intensity at both the cellular and population level. This finding is consistent with the perceptual illusions observed in humans and could provide a potential mechanism for this psychoacoustic effect. PMID:28290533

  9. Mechanisms underlying intensity-dependent changes in cortical selectivity for frequency-modulated sweeps.

    PubMed

    Razak, K A

    2012-04-01

    Frequency-modulated (FM) sweeps are common components of species-specific vocalizations. The intensity of FM sweeps can cover a wide range in the natural environment, but whether intensity affects neural selectivity for FM sweeps is unclear. Bats, such as the pallid bat, which use FM sweeps for echolocation, are suited to address this issue, because the intensity of echoes will vary with target distance. In this study, FM sweep rate selectivity of pallid bat auditory cortex neurons was measured using downward sweeps at different intensities. Neurons became more selective for FM sweep rates present in the bat's echolocation calls as intensity increased. Increased selectivity resulted from stronger inhibition of responses to slower sweep rates. The timing and bandwidth of inhibition generated by frequencies on the high side of the excitatory tuning curve [sideband high-frequency inhibition (HFI)] shape rate selectivity in cortical neurons in the pallid bat. To determine whether intensity-dependent changes in FM rate selectivity were due to altered inhibition, the timing and bandwidth of HFI were quantified at multiple intensities using the two-tone inhibition paradigm. HFI arrived faster relative to excitation as sound intensity increased. The bandwidth of HFI also increased with intensity. The changes in HFI predicted intensity-dependent changes in FM rate selectivity. These data suggest that neural selectivity for a sweep parameter is not static but shifts with intensity due to changes in properties of sideband inhibition.

  10. Frequency Distribution of Seismic Intensity in Japan between 1950 and 2009

    NASA Astrophysics Data System (ADS)

    Kato, M.; Kohayakawa, Y.

    2012-12-01

    JMA Seismic Intensity is an index of seismic ground motion which is frequently used and reported in the media. While it is always difficult to represent complex ground motion with one index, the fact that it is widely accepted in the society makes the use of JMA Seismic Intensity preferable when seismologists communicate with the public and discuss hazard assessment and risk management. With the introduction on JMA Instrumental Intensity in 1996, the number of seismic intensity observation sites has substantially increased and the spatial coverage has improved vastly. Together with a long history of non-instrumental intensity records, the intensity data represent some aspects of the seismic ground motion in Japan. We investigate characteristics of seismic ground motion between 1950 and 2009 utilizing JMA Seismic Intensity Database. Specifically we are interested in the frequency distribution of intensity recordings. Observations of large intensity is rare compared to those of small intensity, and previous studies such as Ikegami [1961] demonstrated that frequency distribution of observed intensity obeys an exponential law, which is equivalent to the Ishimoto-Iida law [Ishimoto & Iida, 1939]. Such behavior could be used to empirically construct probabilistic seismic hazard maps [e.g., Kawasumi, 1951]. For the recent instrumental intensity data as well as pre-instrumental data, we are able to confirm that Ishimoto-Iida law explains the observation. Exponents of the Ishimoto-Iida law, or slope of the exponential law in the semi-log plot, is approximately 0.5. At stations with long recordings, there is no apparent difference between pre-instrumental and instrumental intensities when Ishimoto-Iida law is used as a measure. Numbers of average intensity reports per year and exponents of the frequency distribution curve vary regionally and local seismicity is apparently the controlling factor. The observed numbers of large intensity is slightly less than extrapolated and

  11. 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.

  12. Effect of low-intensity extremely high frequency radiation on reproductive function in wistar rats.

    PubMed

    Subbotina, T I; Tereshkina, O V; Khadartsev, A A; Yashin, A A

    2006-08-01

    The exposure to low-intensity extremely high frequency electromagnetic radiation during spermatogenesis was accompanied by pathological changes, which resulted in degeneration and polymorphism of spermatozoa. The number of newborn rats increased in the progeny of irradiated animals.

  13. Estimation of Thermodynamic and Dynamic Contribution on Regional Precipitation Intensity and Frequency Changes under Global Warming

    NASA Astrophysics Data System (ADS)

    Chen, C.-A.; Chou, C.; Chen, C.-T.

    2012-04-01

    From global point of view, an increased tendency of mean precipitation, which is associated with a shift toward more intense and extreme precipitation, has been found in observations and global warming simulations. However, changes in regional precipitation might be different due to contributions of thermodynamic and dynamic components. It implies that changes in regional rainfall intensity and frequency, which is connected to regional mean precipitation changes, should be more complicated under global warming. To understand how regional intensity and frequency will change under global warming, the global warming simulations from the World Climate Research Programme (WCRP) Coupled Model Intercomparison Project phase 3 (CMIP3) multimodel dataset in the A1B scenario were examined in this study. Over regions with increased mean precipitation, positive precipitation anomaly is usually contributed by more frequent heavy rain and enhanced rainfall intensity, even though there are less light rain events in the future. On the other hand, over regions with decreased mean precipitation, negative precipitation anomaly is associated with decreases in frequency for almost every rain events and weakened rainfall intensity, even though there are more very heavy and light rain events. The thermodynamic component is uniform in different regions, and tends to enhance precipitation frequency and intensity, while the dynamic component varies with regions, and can either enhance or reduce precipitation frequency and intensity.

  14. 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.

  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 and Intensity Stabilization of Planar Waveguide-External Cavity Lasers

    NASA Astrophysics Data System (ADS)

    Tellez, Gregorio; Shoen, Steven; Quetschke, Volker

    2012-02-01

    Planar Waveguide External Cavity Lasers (PW-ECL) show an immense potential for use in precision measurement tasks and space missions because of its compactness and simple design. We show the techniques used to frequency and intensity stabilize a PW-ECL 1550nm laser system with the goal of achieving a frequency stability of 30 Hz/sqrt(Hz) and a RIN of less than 10-6. These PW-ECL systems are a potential replacement for Non-Planar Ring Oscillator (NPRO) laser systems, which have become a standard for low-noise interferometric applications, if the PW-ECL can meet the required stability. We present the initial experimental results of the intensity and frequency stabilization setup and we show a comparison between PW-ECL lasers and NPRO lasers with respect to measurements and applications requiring a high frequency and intensity stability.

  17. 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…

  18. Fast electron beam measurements from relativistically intense, frequency-doubled laser-solid interactions

    NASA Astrophysics Data System (ADS)

    Scott, R. H. H.; Pérez, F.; Streeter, M. J. V.; Clark, E. L.; Davies, J. R.; Schlenvoigt, H.-P.; Santos, J. J.; Hulin, S.; Lancaster, K. L.; Dorchies, F.; Fourment, C.; Vauzour, B.; Soloviev, A. A.; Baton, S. D.; Rose, S. J.; Norreys, P. A.

    2013-09-01

    Experimental measurements of the fast electron beam created by the interaction of relativistically intense, frequency-doubled laser light with planar solid targets and its subsequent transport within the target are presented and compared with those of a similar experiment using the laser fundamental frequency. Using frequency-doubled laser light, the fast electron source size is significantly reduced, while evidence suggests the divergence angle may be reduced. Pyrometric measurements of the target rear surface temperature and the Cu Kα imager data indicate the laser to fast electron absorption fraction is reduced using frequency doubled laser light. Bremsstrahlung measurements indicate the fast electron temperature is 125 keV, while the laser energy absorbed into forward-going fast electrons was found to be 16 ± 4% for frequency doubled light at a mean laser intensity of 5 ± 3 × 1018 W cm-2.

  19. Dependence of low-frequency sonophoresis on ultrasound parameters; distance of the horn and intensity.

    PubMed

    Terahara, T; Mitragotri, S; Kost, J; Langer, R

    2002-03-20

    Sonophoresis at a frequency of 20 kHz has been shown to enhance transdermal drug delivery, a phenomenon referred to as low-frequency sonophoresis. This study provides an investigation of the dependence of low-frequency sonophoresis on various ultrasound parameters, including the distance of the horn from the skin, intensity, and frequency. We performed in vitro experiments with full thickness pig skin to measure enhancements of skin conductivity and drug permeability. Ultrasound was applied to pretreat the skin using a sonicator operating at a frequency of either 20 or 40 kHz. We also measured pitting of aluminum foil to measure cavitation, which is the principal mechanism of low-frequency sonophoresis. The skin conductivity enhancement was found to be inversely proportional to the distance of the horn from the skin. As the intensity increased, skin conductivity enhancement also increased up to a certain threshold, and then dropped off. The intensities (I(max)) at which maximum enhancement occur are about 14 W/cm2 for 20 kHz and 17 W/cm2 for 40 kHz. These findings may be useful in optimizing low-frequency sonophoresis. Overall, the dependence of transport on ultrasound parameters is similar to that of aluminum foil pitting. These results support the role of cavitation in low-frequency sonophoresis.

  20. Cancer in Chiang Mai, North Thailand. A Relative Frequency Study

    PubMed Central

    Menakanit, W.; Muir, C. S.; Jain, D. K.

    1971-01-01

    The relative frequency of histologically diagnosed cancer at the Chiang Mai Medical School in North Thailand in 1964-67 inclusive is examined. Most of the 1877 cancers seen are in Thais (males, 927; females, 908), the remainder arising in Chinese (males, 21; females, 12), Hill People (males, 6; females, 1) and others (females, 2). The cancers in Thais are presented by site, sex and 10-year age-group together with the relative frequency (crude and corrected for age). In Thais, the outstanding finding is the extraordinarily high frequency of cancer of the hypopharyngeal-laryngeal region in both sexes (males, 18.4 per cent; females, 3.4 per cent). This may be associated with the smoking of a local variety of the cigar called “keeyo” This cigar, smoked in the usual manner, contains approximately equal quantities of home-grown, sun-dried, Thai tobacco and the chopped bark of the “koi” tree (Streblus asper). In women, who also smoke “keeyo”, the frequency of hypopharyngeal-laryngeal cancer is unusually high by occidental standards. There is no sex difference in the frequency of bronchial cancer (4 per cent). In males cancer of the penis, in second rank (6.6 per cent) is much more frequent than cancer of the prostate and testis combined. Stomach and skin cancers (ICD 191) are in third place (each 5.7 per cent). In females the most frequent cancers are cervix uteri (19.8 per cent), breast (8.8 per cent) and skin (ICD 191) (6.1 per cent). Cancers of the lip and skin of the head and neck are more frequent in females than in males. Choriocarcinoma is common (1.9 per cent) and there is a large number of vulvar cancers in young women (2.6 per cent). The geography, economy and medical facilities of Chiang Mai Province are described. It is considered that, although there is likely to be considerable under-reporting of internal cancers, the high frequency of hypopharyngeallaryngeal cancer is not due to selective bias. ImagesFig. 2 PMID:5165581

  1. 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.

  2. 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.

  3. The Relation between Frequency of E-Cigarette Use and Frequency and Intensity of Cigarette Smoking among South Korean Adolescents

    PubMed Central

    Lee, Jung Ah; Lee, Sungkyu; Cho, Hong-Jun

    2017-01-01

    Introduction: The prevalence of adolescent electronic cigarette (e-cigarette) use has increased in most countries. This study aims to determine the relation between the frequency of e-cigarette use and the frequency and intensity of cigarette smoking. Additionally, the study evaluates the association between the reasons for e-cigarette use and the frequency of its use. Materials and Methods: Using the 2015 Korean Youth Risk Behavior Web-Based Survey, we included 6655 adolescents with an experience of e-cigarette use who were middle and high school students aged 13–18 years. We compared smoking experience, the frequency and intensity of cigarette smoking, and the relation between the reasons for e-cigarette uses and the frequency of e-cigarette use. Results: The prevalence of e-cigarette ever and current (past 30 days) users were 10.1% and 3.9%, respectively. Of the ever users, approximately 60% used e-cigarettes not within 1 month. On the other hand, 8.1% used e-cigarettes daily. The frequent and intensive cigarette smoking was associated with frequent e-cigarette uses. The percentage of frequent e-cigarette users (≥10 days/month) was 3.5% in adolescents who did not smoke within a month, but 28.7% among daily smokers. Additionally, it was 9.1% in smokers who smoked less than 1 cigarette/month, but 55.1% in smokers who smoked ≥20 cigarettes/day. The most common reason for e-cigarette use was curiosity (22.9%), followed by the belief that they are less harmful than conventional cigarettes (18.9%), the desire to quit smoking (13.1%), and the capacity for indoor use (10.7%). Curiosity was the most common reason among less frequent e-cigarette users; however, the desire to quit smoking and the capacity for indoor use were the most common reasons among more frequent users. Conclusions: Results showed a positive relation between frequency or intensity of conventional cigarette smoking and the frequency of e-cigarette use among Korean adolescents, and frequency of e

  4. Intensity and frequency dependence of laryngeal afferent inputs to respiratory hypoglossal motoneurons.

    PubMed

    Mifflin, S W

    1997-12-01

    Inspiratory hypoglossal motoneurons (IHMs) mediate contraction of the genioglossus muscle and contribute to the regulation of upper airway patency. Intracellular recordings were obtained from antidromically identified IHMs in anesthetized, vagotomized cats, and IHM responses to electrical activation of superior laryngeal nerve (SLN) afferent fibers at various frequencies and intensities were examined. SLN stimulus frequencies <2 Hz evoked an excitatory-inhibitory postsynaptic potential (EPSP-IPSP) sequence or only an IPSP in most IHMs that did not change in amplitude as the stimulus was maintained. During sustained stimulus frequencies of 5-10 Hz, there was a reduction in the amplitude of SLN-evoked IPSPs with time with variable changes in the EPSP. At stimulus frequencies >25 Hz, the amplitude of EPSPs and IPSPs was reduced over time. At a given stimulus frequency, increasing stimulus intensity enhanced the decay of the SLN-evoked postsynaptic potentials (PSPs). Frequency-dependent attenuation of SLN inputs to IHMs also occurred in newborn kittens. These results suggest that activation of SLN afferents evokes different PSP responses in IHMs depending on the stimulus frequency. At intermediate frequencies, inhibitory inputs are selectively filtered so that excitatory inputs predominate. At higher frequencies there was no discernible SLN-evoked PSP temporally locked to the SLN stimuli. Alterations in SLN-evoked PSPs could play a role in the coordination of genioglossal contraction during respiration, swallowing, and other complex motor acts where laryngeal afferents are activated.

  5. Monaural loudness adaptation for middle-intensity middle-frequency signals: the importance of measurement technique.

    PubMed

    Tannen, R S; Weiler, E M; Warm, J S; Dember, W N; Simon, J O

    2001-10-01

    Using the Simple Adaptation technique (SA) and the Ipsilateral Comparison Paradigm (ICP), the authors studied monaural loudness adaptation to a middle-intensity [60 dB(A)] tone at signal frequencies of 250, 1000, and 4000 Hz in the left and right ears. Adaptation effects were absent when the SA procedure was used. However, they were observed uniformly across all frequency values with the ICP, a result that challenges the assertion in the literature, on the basis of SA measures, that loudness adaptation for middle-intensity signals occurs only at frequencies above 4000 Hz. The ICP features periodic intensity modulations (+/-10 dB relative to the base signal) to accommodate listeners' needs for referents by which they can gauge subtle changes in the loudness of the adapting tone, a key component that is missing in the SA method. Adaptation effects in this investigation were similar in both ears, supporting the equal susceptibility assumption common in loudness adaptation studies.

  6. Body mass index, lifetime smoking intensity and lung cancer risk.

    PubMed

    El-Zein, Mariam; Parent, Marie-Elise; Nicolau, Belinda; Koushik, Anita; Siemiatycki, Jack; Rousseau, Marie-Claude

    2013-10-01

    There is as yet no generally accepted explanation for the common finding that low body mass index (BMI) is associated with an increased risk of lung cancer. We investigated this association in a Canadian population-based case-control study (1996-2002) with a particular view to assessing the hypothesis that the observed association was due to residual confounding by smoking. Analyses were based on 1,076 cases and 1,439 controls who provided their height at enrollment and their weight at two points in time, at age 20 and 2 years before enrollment. BMI, in kg/m(2) , was classified into underweight (<18.5), normal (18.5-24.9), overweight (25.0-29.9), and obese (≥30). Smoking history was synthesized into a comprehensive smoking index (CSI) that integrated duration, intensity and time since quitting. Odds ratios (ORs) and 95% confidence intervals (CIs) for BMI-lung cancer associations were estimated, adjusting for CSI as well as several sociodemographic, lifestyle and occupational factors. The normal BMI category was used as the reference. Among those who were underweight at age 20, there was a lower risk of lung cancer (OR = 0.69, 95% CI: 0.50-0.95). Conversely, lung cancer risk was increased among those who were underweight 2 years before enrollment (OR = 2.30, 95% CI: 1.30-4.10). The results were almost identical when stratifying analyses based on smoking history into never/lighter and heavier smokers. The inverse association between recent BMI and lung cancer is unlikely to be largely attributable to residual confounding by smoking. Reverse causality or a true relationship between BMI and lung cancer remain plausible.

  7. 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).

  8. 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).

  9. Quantifying the effect of forests on frequency and intensity of rockfalls

    NASA Astrophysics Data System (ADS)

    Moos, Christine; Dorren, Luuk; Stoffel, Markus

    2017-02-01

    Forests serve as a natural means of protection against small rockfalls. Due to their barrier effect, they reduce the intensity and the propagation probability of falling rocks and thus reduce the occurrence frequency of a rockfall event for a given element at risk. However, despite established knowledge on the protective effect of forests, they are generally neglected in quantitative rockfall risk analyses. Their inclusion in quantitative rockfall risk assessment would, however, be necessary to express their efficiency in monetary terms and to allow comparison of forests with other protective measures, such as nets and dams. The goal of this study is to quantify the effect of forests on the occurrence frequency and intensity of rockfalls. We therefore defined an onset frequency of blocks based on a power-law magnitude-frequency distribution and determined their propagation probabilities on a virtual slope based on rockfall simulations. Simulations were run for different forest and non-forest scenarios under varying forest stand and terrain conditions. We analysed rockfall frequencies and intensities at five different distances from the release area. Based on two multivariate statistical prediction models, we investigated which of the terrain and forest characteristics predominantly drive the role of forest in reducing rockfall occurrence frequency and intensity and whether they are able to predict the effect of forest on rockfall risk. The rockfall occurrence frequency below forested slopes is reduced between approximately 10 and 90 % compared to non-forested slope conditions; whereas rockfall intensity is reduced by 10 to 70 %. This reduction increases with increasing slope length and decreases with decreasing tree density, tree diameter and increasing rock volume, as well as in cases of clustered or gappy forest structures. The statistical prediction models reveal that the cumulative basal area of trees, block volume and horizontal forest structure represent key

  10. [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.

  11. 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.

  12. Regional and yearly variations of hail frequency and intensity in France

    NASA Astrophysics Data System (ADS)

    Berthet, C.; Dessens, J.; Sanchez, J. L.

    2011-06-01

    In addition to the ground seeding hail prevention project, the Association Nationale d'Etude et de Lutte contre les Fléaux Atmosphériques (ANELFA) operates hailpad networks in four of the most hailed regions of France: Atlantic, Pyrenean, Central and Mediterranean. During the past 22 years of continuous measurements, more than five thousand point hailfalls have been recorded at 922 stations (mean annual value) installed in a 66,500 km² area. At the scale of a region and of a hail season, hail is found to be the product of two nearly independent parameters, the frequency and the mean intensity of hailfalls. The frequency is highest in the Pyrenean region, while the intensity is highest both in the Pyrenean and Central regions. This can be explained, for the frequency, by the proximity of Spain, and, for the intensity, by the mean hailstone size distributions which are different in the continental and maritime regions. The time variations and trends of hail during the 1989-2009 period are computed from the data at 457 stations which never changed during this period. The annual frequency is subject to cyclic variations, while the yearly mean intensity is affected by irregular severe hail events. The frequency did not change significantly during the period, while the intensity increased by 70%. The mean monthly distribution of hail is bimodal, with two maximums in May and July, suggesting that two types of meteorological conditions are at the origin of hailstorms. April and May are solely responsible for the mean hail increase observed during the period. A computation of the year-to-year correlation between hail intensity and mean minimum surface temperature for each month suggests that the large hail increase in April and May is at least partially due to the observed concomitant increase in temperature, and then may be a consequence of global warning.

  13. 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.

  14. 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…

  15. 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…

  16. Effects of intensity and frequency of crown damage on resprouting of Erica arborea L. (Ericaceae)

    NASA Astrophysics Data System (ADS)

    Riba, Miquel

    1998-02-01

    A clipping experiment was conducted to analyse the effects of intensity and frequency of crown damage on compensatory responses by resprouting in the shrub species Erica arborea. Increased sprout removal (crown damage intensity) promoted recruitment and increased the total dry weight of new sprout cohorts. Mean size (diameter) of new sprout cohorts was greater under increased intensity of crown damage, although no differences in size variability (CV) were obtained. Increased crown damage events stimulated recruitment of new sprouts, but had no effect on their total dry weight and reduced their mean size. Increased intensity and frequency of crown damage also promoted growth (RGR) of uncut sprouts according to local position on the lignotuber. The results show that qualitatively different compensatory responses can be obtained depending on the modular structure of the genet and the frequency and intensity of crown damage. They also suggest that competition for underground resources might be important for explaining the interactions among sprouts within the genet. Modular behavior in resprouting species under extreme disturbance regimes (e.g. heavy grazing after fire) is also expected to have a negative effect on overall genet growth and reproduction.

  17. Peri-threshold encoding of stimulus frequency and intensity in the M100 latency.

    PubMed

    Stufflebeam, S M; Poeppel, D; Rowley, H A; Roberts, T P

    1998-01-05

    Recent work has suggested that, in addition to spatial tonotopy, pitch and timbre information may be encoded in the temporal activity of the auditory cortex. Specifically, the post-stimulus latency of the maximal cortical evoked neuromagnetic field (M100 or N1m) is a function of stimulus frequency. We investigated the additional effect of varying the stimulus intensity on the M100 response. A 37-channel biomagnetometer recorded neuromagnetic fields over the temporal lobe of healthy volunteers in response to monaurally presented tones. The frequency dependence of the M100 latency remained remarkably invariant even at low stimulus intensity. Thus, for peri-threshold stimuli, frequency information appears encoded in the temporal form of the evoked response.

  18. 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.

  19. 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.

  20. The effect of rainfall trends in the estimation of intensity-duration-frequency curves

    NASA Astrophysics Data System (ADS)

    Carvalho, S. C. P.; de Lima, M. I. P.; de Lima, J. L. M. P.; Coelho, M. F. E. S.

    2010-05-01

    Intensity-duration-frequency (IDF) curves are extensively used as tools for the planning and design of many engineering projects. The design of urban drainage systems is an example where short-duration extreme rainfall has particular importance. The estimation of IDF curves is based on the assumption that the rainfall time series are stationary. However, the observed intensity-frequency relation in rain does not stay unchanged over time. Recent studies are stressing that in the next decades more frequent extreme rainfall events, of a given magnitude, could be expected. Thus, it is pertinent to understand the information in the IDF curves in the context of a changing climate. This work focuses on characterizing the effect of trends in short-term rainfall on the estimation of IDF curves. The study uses rainfall-intensity annual maxima for 5, 10, 15, 30 and 60 minutes events. The data are from 11 meteorological stations, located in Mainland Portugal; the record lengths range from 29 to 41 years. Two versions of IDF curves were obtained: one was estimated from the original series and the other one from the series obtained after the trend component was removed. For each rainfall event-duration, the intensity trend was studied using the Mann-Kendall nonparametric test and the Sen's nonparametric method. Although the majority of the rainfall series did not exhibit any sign of statistically significant trends, the characterization of the effect of those trends (or changes of behaviour over time) on the IDF curves suggests that there is a need to revise and update the existing formulation of the intensity-duration-frequency relationships. Whilst, in general, the analyses reveal no simple pattern for changes in the rainfall process over time and for different geographical locations, we are led to conclude that hydrological risk assessment should pay attention to the increased uncertainty in rainfall intensity-duration-frequency estimations.

  1. Bio-effects and safety of low-intensity, low-frequency ultrasonic exposure.

    PubMed

    Ahmadi, Farzaneh; McLoughlin, Ian V; Chauhan, Sunita; ter-Haar, Gail

    2012-04-01

    Low-frequency (LF) ultrasound (20-100 kHz) has a diverse set of industrial and medical applications. In fact, high power industrial applications of ultrasound mainly occupy this frequency range. This range is also used for various therapeutic medical applications including sonophoresis (ultrasonic transdermal drug delivery), dentistry, eye surgery, body contouring, the breaking of kidney stones and eliminating blood clots. While emerging LF applications such as ultrasonic drug delivery continue to be developed and undergo translation for human use, significant gaps exist in the coverage of safety standards for this frequency range. Accordingly, the need to understand the biological effects of LF ultrasound is becoming more important. This paper presents a broad overview of bio-effects and safety of LF ultrasound as an aid to minimize and control the risk of these effects. Its particular focus is at low intensities where bio-effects are initially observed. To generate a clear perspective of hazards in LF exposure, the mechanisms of bio-effects and the main differences in action at low and high frequencies are investigated and a survey of harmful effects of LF ultrasound at low intensities is presented. Mechanical and thermal indices are widely used in high frequency diagnostic applications as a means of indicating safety of ultrasonic exposure. The direct application of these indices at low frequencies needs careful investigation. In this work, using numerical simulations based on the mathematical and physical rationale behind the indices at high frequencies, it is observed that while thermal index (TI) can be used directly in the LF range, mechanical index (MI) seems to become less reliable at lower frequencies. Accordingly, an improved formulation for the MI is proposed for frequencies below 500 kHz.

  2. Low Frequency Propagation and Observed Intensity Pattern of Jovian Radio Emissions

    NASA Astrophysics Data System (ADS)

    Lecacheux, A.

    Low frequency radio emissions from Jupiter have been extensively observed by sev- eral spacecraft (Voyager, Ulysses, Galileo and, more recently, Cassini), but some of their basic properties (exact location, radiation pattern) are still in discussion or just inferred. The whole set of observations were carried out within a few degrees from the Jovian equatorial plane (with the only exception of Ulysses in its outbound trajectory). As a consequence, radio sources were usually observed after propagation through the Io plasma torus, whose maximum critical frequency (about 0.5 MHz) is comparable in magnitude to the frequency range of HOM (hectometric) and DAM (decametric) components. One can expect several kinds of propagation effects: at small scales, in- cluding diffractive scintillation linked to turbulence properties of the medium, and at large scales, due to refraction by the Io torus, which optically acts as a diverging lens. The aim of this presentation is to examine the latter kind of effects and, in particu- lar, to quantitatively assess the spatial distribution of intensity from a small radiating source at Jupiter, when observed far from the planet through the Io plasma torus. A specific ray tracing calculation in dispersive inhomogeneous plasma was developped for this purpose, allowing the computation of both ray trace and ray intensity along its path. The method permits the determination of spatial directions from where one can observe intensity reduction (shadow zone) as well as intensity amplification (focusing and caustics) of radiation from a point source. While highly depending on the accu- racy of the used Io torus electron density model, the performed calculations show that substantial intensity drops and rises are to be expected in the lower frequency range up to several MHz. This may provide an alternative explanation for the absorption band recently described in the literature as a permanent feature of the HOM emission.

  3. Multidie LED combined with homogenizing optics to improve frequency response and intensity for FLIM applications.

    PubMed

    Liu, H-T; Lin, W-L; Feng, Y-L; Lin, Y; Chen, Y-C

    2017-03-15

    Application of light-emitting diodes (LEDs) in frequency-domain fluorescence lifetime imaging microscopy (FLIM) has been limited by the trade-off between modulation frequency and illumination intensity of LEDs, which affects the signal-to-noise ratio in fluorescence lifetime measurements. To increase modulation frequency without sacrificing output power of LEDs, we propose to use LEDs with multiple dice connected in series. The LED capacitance was reduced with series connection; therefore, the frequency response of multidie LED was significantly increased. LEDs in visible light, including blue, green, amber and red, were all applicable in FLIM. We also present a homogenizing optics design, so that multidie LEDs produced uniform illumination on the same focal spot. When the homogenizing optics was combined with multicolour emitters, it provides multiple colour selection in a compact and convenient design.

  4. Electric-field effects on the OH vibrational frequency and infrared absorption intensity for water

    NASA Astrophysics Data System (ADS)

    Hermansson, Kersti

    1993-07-01

    The variations of the anharmonic OH frequency and the infrared absorption intensity with field strength have been calculated for the uncoupled OH stretching vibration of a water molecule in a static, homogeneous electric field using ab initio methods at the MP4 level with a nearly saturated basis set. The OH frequency is found to be virtually independent of the field components perpendicular to the vibrating OH bond. For the parallel component, the frequency vs field curve is close to quadratic, with a maximum for a slightly negative (directed from H to O) field strength. The external field perturbation, defined as Vext(E∥,rOH)=Vtot(E∥, rOH)-Vfree(rOH), is found to be closely linear in rOH, except when the field strength E∥ is both large and negative. The linear external force constant is almost perfectly accounted for by the sum of two terms, -E∥ṡdμ∥free/drOH and -1/2ṡE∥ṡ∂μ∥induced/∂rOH. These derivatives are quite insensitive to the choice of basis-set. The ∂μ∥induced/∂rOH derivative is approximately proportional to E∥, and gives rise to the arclike shape of the frequency vs field curve. The frequency maximum occurs where ∂μ∥tot/∂rOH≊0. It is the sign of dμ∥free/drOH which determines that the frequency maximum occurs at a negative field strength for water (but at a positive field strength for OH-, for example), i.e., that a frequency red-shift (blue-shift for OH-) occurs when the molecule is bound. The linear relationship between the infrared absorption intensity and frequency of the water OH vibration is derived.

  5. Generation of Low-Frequency Electromagnetic Waves by Spectrally Broad Intense Laser Pulses in a Plasma

    NASA Astrophysics Data System (ADS)

    Tsintsadze, L. N.; Tajima, T.; Nishikawa, K.; Koga, J. K.; Nakagawa, K.; Kishimoto, Y.

    A new mechanism for the emission of low-frequency electromagnetic (EM) waves, including the generation of a quasistatic magnetic field, by a relativistically intense laser pulse with a wide spectrum is presented. The emission is due to modulational and filamentational instabilities of the photon gas in a plasma. The generation of the magnetic field is associated with a significant change in the laser pulse shape during the propagation. This process is identified in our 2D particle-in-cell (PIC) simulations with a high intensity (1019

  6. Mid-frequency acoustic propagation in shallow water on the New Jersey shelf: mean intensity.

    PubMed

    Tang, Dajun; Henyey, Frank S; Wang, Zhongkang; Williams, Kevin L; Rouseff, Daniel; Dahl, Peter H; Quijano, Jorge; Choi, Jee Woong

    2008-09-01

    Mid-frequency (1-10 kHz) sound propagation was measured at ranges 1-9 km in shallow water in order to investigate intensity statistics. Warm water near the bottom results in a sound speed minimum. Environmental measurements include sediment sound speed and water sound speed and density from a towed conductivity-temperature-depth chain. Ambient internal waves contribute to acoustic fluctuations. A simple model involving modes with random phases predicts the mean transmission loss to within a few dB. Quantitative ray theory fails due to near axial focusing. Fluctuations of the intensity field are dominated by water column variability.

  7. 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.

  8. 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.

  9. Effects of low-intensity ultrahigh frequency electromagnetic radiation on inflammatory processes.

    PubMed

    Lushnikov, K V; Shumilina, Yu V; Yakushina, V S; Gapeev, A B; Sadovnikov, V B; Chemeris, N K

    2004-04-01

    Low-intensity ultrahigh frequency electromagnetic radiation (42 GHz, 100 microW/cm(2)) reduces the severity of inflammation and inhibits production of active oxygen forms by inflammatory exudate neutrophils only in mice with inflammatory process. These data suggest that some therapeutic effects of electromagnetic radiation can be explained by its antiinflammatory effect which is realized via modulation of functional activity of neutrophils in the focus of inflammation.

  10. Quantitative explanation of strong multi-frequency intensity scintillation spectra using refractive scattering

    NASA Astrophysics Data System (ADS)

    Vats, H. O.; Booker, H. G.; Majidiahi, G.

    1981-12-01

    Strong intensity spectra were observed simultaneously by Vats (1981) on transmissions through the ionospheric F-region at 40, 140, and 360 MHz from a stationary satellite. These spectra are explained quantitatively in terms of refractive scattering, using the approach of Booker and MajidiAhi (1981). The outer and inner scales are 50 km and 5 m, respectively, and the integrated mean square fluctuation of ionization density is 10 to the 28th/m. The spectral index of three produces the correct spectral behavior at high fluctuation frequencies, and the correct ratios of the upper roll-off frequencies at three wave frequencies. The rms fluctuation of phase is about 130 rad at 360 MHz, 340 rad at 140 MHz, and 1200 rad at 40 MHz. At 40 MHz, the scale of the intensity fluctuation at ground level is about 10 m; removal of almost all fluctuations in the ionosphere at scales below the Fresnel scale leaves the fine structure of the intensity spectrum at ground level virtually unaffected.

  11. Quantitative explanation of strong multi-frequency intensity scintillation spectra using refractive scattering

    NASA Astrophysics Data System (ADS)

    O. Vats, Hari; Booker, Henry G.; Majidiahi, Gholamreza

    Under evening equatorial conditions, strong intensity spectra observed simultaneously on transmissions through the ionospheric F-region at 40, 140 and 360 MHz from a stationary satellite are explained quantitatively in terms of refractive scattering using the approach of BOOKER and MAJIDIAHI (1981). Use is made of an outer scale (wavelength/2gp) of 50 km, an inner scale of 5 m and an integrated mean square fluctuation of ionization density [ ∝ overline(ΔN) 2dz] of 10 28 m -5. The spectral index required to fit the observations is 3, and no major departure from this value is permissible either way. This produces the correct spectral behavior at high fluctuation frequencies and the correct ratios of the upper roll-off frequencies at the three wave frequencies. The RMS fluctuation of phase is about 130 rad at 360 MHz, 340 rad at 140 MHz and 1200 rad at 40 MHz. At 40MHz the scale of the intensity fluctuation at ground level is about 10m, and this is caused by refractive scattering in the ionosphere at scales of the order of the outer scale; removal of practically all fluctuations in the ionosphere at scales below the Fresnel scale leaves the fine structure of the intensity spectrum at ground level virtually unaffected.

  12. 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.

  13. Circularly polarized harmonic generation by intense bicircular laser pulses: electron recollision dynamics and frequency dependent helicity

    NASA Astrophysics Data System (ADS)

    Bandrauk, André D.; Mauger, François; Yuan, Kai-Jun

    2016-12-01

    Numerical solutions of time-dependent Schrödinger equations for one and two electron cyclic molecules {{{H}}}nq+ exposed to intense bichromatic circularly polarized laser pulses of frequencies {ω }1 and {ω }2, such that {ω }1/{ω }2={n}1/{n}2 (integer) produce circularly polarized high order harmonics with a cut-off recollision maximum energy at and greater than the linear polarization law (in atomic units) {N}m{ω }1={I}p+3.17{U}p, where I p is the ionization potential and {U}p={(2{E}0)}2/4{ω }2 is the ponderomotive energy defined by the field E 0 (intensity I={{cE}}02/8π ) from each pulse and mean frequency ω =({ω }1+{ω }2)/2 . An electron recollision model in a rotating frame at rotating frequency {{Δ }}ω =({ω }1-{ω }2)/2 predicts this simple result as a result of recollision dynamics in a combination of bichromatic circularly polarized pulses. The harmonic helicities and their intensities are shown to depend on compatible symmetries of the net pulse electric fields with that of the molecules.

  14. Formulation of Intensity-Duration-Frequency Curves Incorporating Non-Stationarity

    NASA Astrophysics Data System (ADS)

    Yousef, L. A.; Ouarda, T.

    2013-12-01

    The methodology behind the formulation of Intensity-Duration-Frequency (IDF) curves dates back to the 1930's. They are a commonly used tool in the planning and design of water-related projects. The principle of any IDF formula is to find the relationship between three variables of rainfall events: the intensity of the event, its duration, and its expected frequency. The general IDF methodology proposed by Koutsoyiannis et al. (1998) provides a simple expression of the relationship between the intensity of rainfall with its duration and frequency. The use of this general relationship has become increasingly popular in the literature, due to how it eliminates the complexity involved with other alternative relationships. Current research advances recognize the existence of non-stationarity in records of hydroclimatic variables, rendering it necessary for it to be incorporated into analyses involving these variables. Non-stationarity is caused by the changes in climate and environment across the world. Numerous studies have proven that neglecting to incorporate non-stationarity does have an impact on the results of modeling hydroclimatic variables. Examples of models worked with previously, taking non-stationarity into consideration, are Flood-Duration-Frequency (QDF) and Flood-Frequency-Analysis (FFA). The purpose of this study is to incorporate the non-stationarity that exists in rainfall records into the general IDF relationship, by making the parameters involved in it time-dependent. The Generalized Extreme Value (GEV) distribution is proposed as the distribution function to be used with the time dependent numerator of the general IDF relationship. Generalized Maximum Likelihood (GML) estimators are proposed to be used for determining the parameters of the GEV function, based on the work of El Adlouni et al. (2007).

  15. 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

  16. Estimation of bending wave intensity in beams using the frequency response technique

    NASA Astrophysics Data System (ADS)

    Linjama, J.; Lahti, T.

    1992-02-01

    The frequency response approach is applied to the measurement of bending wave intensity, with two or four accelerometers being used. Based on the known structural intensity equations, a comprehensive set of frequency domain expressions is derived for power measurements in a beam. A practical procedure is developed for the general four-transducer method, which allows a usual dual channel FFT analyzer to be employed in multi-channel measurements. The procedure uses the sequential frequency response technique, and is applicable if the situation remains stationary during the data acquisition. In addition, expressions are derived for the determination of the force- and moment-related bending wave power components separately. In a laboratory experiment, the power carried by bending waves was measured in a simple beam, and the methods developed were tested and compared. The frequency response approach was shown to work well in detecting the total power. The estimation of the two bending wave power components, both in the near and the far field, was also demonstrated.

  17. 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

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

    NASA Astrophysics Data System (ADS)

    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.

  19. EFFECTS OF FREQUENCY OF WRITING AND INTENSITY OF TEACHER EVALUATION UPON HIGH SCHOOL STUDENTS' PERFORMANCE IN WRITTEN COMPOSITION.

    ERIC Educational Resources Information Center

    ARNOLD, LOIS V.; BURTON, DWIGHT L.

    THE PROBLEM OF THIS RESEARCH WAS TO INVESTIGATE THE EFFECTS OF FREQUENCY OF WRITING AND INTENSITY OF TEACHER EVALUATION UPON PERFORMANCE BY STUDENTS OF VARYING ABILITIES. THE STUDY WAS DESIGNED TO INCLUDE EIGHT 10TH-GRADE CLASSES WITH TWO TEACHERS FOLLOWING FOUR DIFFERENT APPROACHES TO INTENSITY OF TEACHER EVALUATION AND FREQUENCY OF WRITING.…

  20. [Pain relief by low-intensity frequency-modulated millimeter waves acting on the acupuncture points].

    PubMed

    Samosiuk, I Z; Kulikovich, Iu N; Tamarova, Z A; Samosiuk, N I; Kazhanova, A K

    2000-01-01

    Analgetic effect of low-intensive frequency-modulated millimetric waves (MW) was studied in mice with formalin induced nociceptive behavior reaction (licking of defeat hindpaw). MW were applied to the acupoint E 36 of the defeat hindpaw. The following MW were used: 60 GHz (1) and 118 GHz (2) which were modulated by 4 Hz; noise MW within the range of 42-95 GHz (3) and 90-140 GHz (4) which were modulated in accidental order by frequencies 1-60 Hz; combinations of fixed frequencies with noise - 60 GHz + noise 42-95 GHz (5) and 118 GHz + noise 90-140 GHz (6). All used MW combinations suppressed licking of the defeat hindpaw and increased duration of sleep and eating. The strongest analgesia was achieved in series 1-3 (42.4-69.7%), the weakest in series 6 and 4 of the experiment (12.2-19.7%).

  1. An intense, cold, velocity-controlled molecular beam by frequency-chirped laser slowing

    NASA Astrophysics Data System (ADS)

    Truppe, S.; Williams, H. J.; Fitch, N. J.; Hambach, M.; Wall, T. E.; Hinds, E. A.; Sauer, B. E.; Tarbutt, M. R.

    2017-02-01

    Using frequency-chirped radiation pressure slowing, we precisely control the velocity of a pulsed CaF molecular beam down to a few m s–1, compressing its velocity spread by a factor of 10 while retaining high intensity: at a velocity of 15 m s–1 the flux, measured 1.3 m from the source, is 7 × 105 molecules per cm2 per shot in a single rovibrational state. The beam is suitable for loading a magneto-optical trap or, when combined with transverse laser cooling, improving the precision of spectroscopic measurements that test fundamental physics. We compare the frequency-chirped slowing method with the more commonly used frequency-broadened slowing method.

  2. 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

  3. [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.

  4. Coupled solitons of intense high-frequency and low-frequency waves in Zakharov-type systems.

    PubMed

    Gromov, Evgeny; Malomed, Boris

    2016-12-01

    One-parameter families of exact two-component solitary-wave solutions for interacting high-frequency (HF) and low-frequency (LF) waves are found in the framework of Zakharov-type models, which couple the nonlinear Schrödinger equation for intense HF waves to the Boussinesq (Bq) or Korteweg-de Vries (KdV) equation for the LF component through quadratic terms. The systems apply, in particular, to the interaction of surface (HF) and internal (LF) waves in stratified fluids. These solutions are two-component generalizations of the single-component Bq and KdV solitons. Perturbed dynamics and stability of the solitary waves are studied in detail by means of analytical and numerical methods. Essentially, they are stable against separation of the HF and LF components if the latter one is shaped as a potential well acting on the HF field, and unstable, against splitting of the two components, with a barrier-shaped LF one. Collisions between the solitary waves are studied by means of direct simulations, demonstrating a trend to merger of in-phase solitons, and elastic interactions of out-of-phase ones.

  5. Coupled solitons of intense high-frequency and low-frequency waves in Zakharov-type systems

    NASA Astrophysics Data System (ADS)

    Gromov, Evgeny; Malomed, Boris

    2016-12-01

    One-parameter families of exact two-component solitary-wave solutions for interacting high-frequency (HF) and low-frequency (LF) waves are found in the framework of Zakharov-type models, which couple the nonlinear Schrödinger equation for intense HF waves to the Boussinesq (Bq) or Korteweg-de Vries (KdV) equation for the LF component through quadratic terms. The systems apply, in particular, to the interaction of surface (HF) and internal (LF) waves in stratified fluids. These solutions are two-component generalizations of the single-component Bq and KdV solitons. Perturbed dynamics and stability of the solitary waves are studied in detail by means of analytical and numerical methods. Essentially, they are stable against separation of the HF and LF components if the latter one is shaped as a potential well acting on the HF field, and unstable, against splitting of the two components, with a barrier-shaped LF one. Collisions between the solitary waves are studied by means of direct simulations, demonstrating a trend to merger of in-phase solitons, and elastic interactions of out-of-phase ones.

  6. Intensity modulated radiation therapy for breast cancer: current perspectives

    PubMed Central

    Buwenge, Milly; Cammelli, Silvia; Ammendolia, Ilario; Tolento, Giorgio; Zamagni, Alice; Arcelli, Alessandra; Macchia, Gabriella; Deodato, Francesco; Cilla, Savino; Morganti, Alessio G

    2017-01-01

    Background Owing to highly conformed dose distribution, intensity modulated radiation therapy (IMRT) has the potential to improve treatment results of radiotherapy (RT). Postoperative RT is a standard adjuvant treatment in conservative treatment of breast cancer (BC). The aim of this review is to analyze available evidence from randomized controlled trials (RCTs) on IMRT in BC, particularly in terms of reduction of side effects. Methods A literature search of the bibliographic database PubMed, from January 1990 through November 2016, was performed. Only RCTs published in English were included. Results Ten articles reporting data from 5 RCTs fulfilled the selection criteria and were included in our review. Three out of 5 studies enrolled only selected patients in terms of increased risk of toxicity. Three studies compared IMRT with standard tangential RT. One study compared the results of IMRT in the supine versus the prone position, and one study compared standard treatment with accelerated partial breast IMRT. Three studies reported reduced acute and/or late toxicity using IMRT compared with standard RT. No study reported improved quality of life. Conclusion IMRT seems able to reduce toxicity in selected patients treated with postoperative RT for BC. Further analyses are needed to better define patients who are candidates for this treatment modality. PMID:28293119

  7. 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

  8. Vibrotactile perceived intensity for mobile devices as a function of direction, amplitude, and frequency.

    PubMed

    Hwang, Inwook; Seo, Jongman; Kim, Myongchan; Choi, Seungmoon

    2013-01-01

    Vibrotactile rendering is an emerging interaction method for information transmission in mobile devices, replacing or supplementing visual and auditory displays. To design effective vibrotactile actuators or display algorithms, an understanding of the perceived intensity (strength) of their vibrations is essential. This paper aims to build a robust model for the perceived intensities of mobile device vibrations, which can be immediately used by engineers and application designers. To this end, we carried out two psychophysical experiments using absolute magnitude estimation procedures. In Experiment I, we investigated the effects of vibration direction and device weight on the perceived intensity of mobile device vibrations. The vibration directions tested (height, width, and depth), and the device weights (90-130 g) were determined considering those of contemporary mobile devices. Only the vibration direction was found to be a statistically significant factor, showing the highest perceived intensities along the height direction of a mobile device. In Experiment II, we measured the perceived intensities of vibrations with various amplitudes and frequencies along the three vibration directions. Then, for each direction, a psychophysical magnitude function and equal sensation contours were constructed based on Stevens' power law, which clearly visualize the consequences of vibration parameter changes on the resulting perceptual strength. In addition, we found a monotonic relationship between the physical power of vibration absorbed by the hand and the resulting perceived intensity. This suggests that the former, which is greatly easier to acquire in practice, is a reliable predictor of the latter. We expect that the results of this study can provide immediate knowledge about the perceptual strength of vibrations that engineers and applications developers will find useful.

  9. 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.

  10. 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.

  11. Intensity-modulated radiotherapy for neoadjuvant treatment of gastric cancer

    SciTech Connect

    Knab, Brian; Rash, Carla; Farrey, Karl; Jani, Ashesh B. . E-mail: jani@rover.uchicago.edu

    2006-01-01

    Radiation therapy plays an integral role in the treatment of gastric cancer in the postsurgery setting, the inoperable/palliative setting, and, as in the case of the current report, in the setting of neoadjuvant therapy prior to surgery. Typically, anterior-posterior/posterior-anterior (AP/PA) or 3-field techniques are used. In this report, we explore the use of intensity-modulated radiotherapy (IMRT) treatment in a patient whose care was transferred to our institution after 3-field radiotherapy (RT) was given to a dose of 30 Gy at an outside institution. If the 3-field plan were continued to 50 Gy, the volume of irradiated liver receiving greater than 30 Gy would have been unacceptably high. To deliver the final 20 Gy, an opposed parallel AP/PA plan and an IMRT plan were compared to the initial 3-field technique for coverage of the target volume as well as dose to the kidneys, liver, small bowel, and spinal cord. Comparison of the 3 treatment techniques to deliver the final 20 Gy revealed reduced median and maximum dose to the whole kidney with the IMRT plan. For this 20-Gy boost, the volume of irradiated liver was lower for both the IMRT plan and the AP/PA plan vs. the 3-field plan. Comparing the IMRT boost plan to the AP/PA boost-dose range (<10 Gy) in comparison to the AP/PA plan; however, the IMRT plan irradiated a smaller liver volume within the higher dose region (>10 Gy) in comparison to the AP/PA plan. The IMRT boost plan also irradiated a smaller volume of the small bowel compared to both the 3-field plan and the AP/PA plan, and also delivered lower dose to the spinal cord in comparison to the AP/PA plan. Comparison of the composite plans revealed reduced dose to the whole kidney using IMRT. The V20 for the whole kidney volume for the composite IMRT plan was 30% compared to approximately 60% for the composite AP/PA plan. Overall, the dose to the liver receiving greater than 30 Gy was lower for the composite IMRT plan and was well below acceptable limits

  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. 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.

  14. 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.

  15. Extremely low frequency fields and cancer: laboratory studies

    SciTech Connect

    Anderson, Larry E. )

    1998-10-01

    There is now convincing evidence from a large number of laboratories, that exposure to extremely low frequency (ELF) magnetic and electric fields produces biological responses in animals. However, no animal studies clearly demonstrate deleterious effects of ELF fields, although several are suggestive of potential health impacts. A major current emphasis in laboratory research is to determine whether or not the reported epidemiological studies that suggest an association between EMF exposure and risk of cancer are supported in studies using animal models. Several approaches are outlined in the experimental approach to this question. With specific reference to the radiofrequencies (RF) associated with wireless technology, even less research has been carried out than with ELF. Particularly, in regard to research on carcinogenesis and RF exposure in animals, little is known This section addresses laboratory studies in animals exposed to extremely low-power-frequency EMF, the relevance of which, to RF, is unknown. However, the approaches used with ELF may be useful in guiding laboratory research on the issue of RF exposure and cancer. From the perspective of laboratory animal studies, this paper will discuss studies investigating the potential relationship between ELF magnetic and/or electric field exposure and the risk of cancer.

  16. 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.

  17. 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.

  18. Intensity-Duration-Frequency (IDF) rainfall curves, for data series and climate projection in African cities

    NASA Astrophysics Data System (ADS)

    De Paola, Francesco; Giugni, Maurizio; Topa, Maria Elena; Coly, Adrien; Yeshitela, Kumelachew; Kombe, Wilbard; Tonye, Emmanuel; Touré, Hamidou

    2013-04-01

    The intensity-duration-frequency curves are used in hydrology to express in a synthetic way, the link between the maximum rainfall height h and a generic duration d of a rainfall event, fixed a given return period T. Generally, IDF curves can be characterized by a bi-parameter power law: h(d,T) = a(T)dn where a(T), and n are the parameters that have to be estimated through a probabilistic approach. An intensity-duration-frequency analysis starts by gathering time series record of different durations and extracting annual extremes for each duration. The annual extreme data are then fitted by a probability distribution. The present study, carried out within the FP7-ENV-2010 CLUVA project (CLimate change and Urban Vulnerability in Africa), regards the evaluation of the IDF curves for five case studies: Addis Ababa (Ethiopia), Dar Es Salaam (Tanzania), Douala (Cameroon), Ouagadouogou (Burkina Faso) and Saint Louis (Senegal). The probability distribution chosen to fit the annual extreme data is the classic Gumbel distribution. However, for the case studies, only the maximum annual daily rainfall heights are available. Therefore, to define the IDF curves and the extreme values in a smaller time window (10', 30', 1h, 3h, 6h, 12h), it is required to develop disaggregation techniques of the collected data, in order to generate a synthetic sequence of rainfall, with statistical properties equal to the recorded data. The daily rainfalls were disaggregated using two models: short-time intensity disaggregation model (10', 30', 1h); cascade-based disaggregation model (3h, 6h, 12h). On the basis of disaggegation models and Gumbel distribution , the parameters of the IDF curves for the five test cities were evaluated. In order to estimate the contingent influence of climate change on the IDF curves, the illustrated procedure has been applied to the climate (rainfall) simulations over the time period 2010-2050 provided by the CMCC (Centro Euro-Mediterraneo sui Cambiamenti Climatici

  19. Assessing Climate change Impacts to Rainfall Intensity-Duration-Frequency Curves over the Florida Panhandle &Peninsula

    NASA Astrophysics Data System (ADS)

    Ghosh, D. K.; Wang, D.; Obeysekera, J.; Hagen, S. C.

    2013-12-01

    The type, amount, intensity and frequency of rainfall are being directly influenced and altered due to potential climate changes. Consideration should be given to a revision of the rainfall intensity-duration-frequency (IDF) curve, developed based on the historical rainfall data, for storm water drainage design and flood control facilities. Proper adaptation by quantifying the potential effects of climate changes is one of the major ways to reduce vulnerability. As a result, updating IDF curves based on the future climate condition is very important for managing the hydraulic structures. In this study, the climate change impact to rainfall IDF curves over the Florida panhandle and peninsula are assessed using the COAPS Regional Downscaling data from the Florida Climate Institute. The COAPS Land-Atmosphere Regional Ensemble Climate Change Experiment for the Southeast United States at 10-km resolution consists of three regional climate models (RCM) by downscaling the general circulation models: the Community Climate System Model (CCSM), the Hadley Centre Coupled Model version 3 (HadCM3), and the Geophysical Fluid Dynamics Laboratory GCM (GFDL). The RCMs have been performed for the historical simulations (1969-1999) and the future projections (2038-2070) under the AR4 A2 emissions scenario. In this study, more than 30-years of hourly precipitation data are gathered from 57 weather stations in Florida. The performance of the RCMs is evaluated by comparing historical simulations with observations. The parameters of generalized extreme value (GEV) distributions including location, scale, and shape parameters are mapped for the period of 1969-1999 and 2038-2070. The spatial distribution map of rainfall intensity under various durations and return periods will be presented. The response on the Florida panhandle will be compared and contrasted with that of the larger peninsula. These maps will provide insight that can lead to a useful engineering tool for designing the

  20. Impact of climate change on intensity-duration-frequency (IDF) curves in the United States

    NASA Astrophysics Data System (ADS)

    Zhu, J.

    2013-12-01

    Changes in climate may potentially alter extreme rainfall intensity in most regions. In order for government agencies and design engineers to incorporate potential future changes into assessment and design processes, tools for planning and design should be capable of considering non-stationary climate conditions. In this study, potential changes in intensity-duration-frequency (IDF) curves at a range of locations in the United States, which are often used for assessment of extreme rainfall events, are explored using climate model historic runs, reanalysis runs, and future climate projections. The concept of the adjustment factor, which represents the general ability of climate models in representing the reanalysis data that is a reasonable estimate of actual gridded historical climate at the model grid scale, is applied to investigate potential impacts of climate change on IDF curves. For most of the study regions, future climate projections suggest an increase in the intensity of extreme storms for a given return period and duration with strong regional variations. The results also reveal the dependence of the adjustment factor values on return period and storm durations as related to the characteristics of extreme rainfalls, as it varies significantly with region, storm duration, and return period. We illustrate that impacts of climate change on extreme hydrologic events are highly regional and thus such assessments should be performed for specific locations.

  1. Direct ultrashort-pulse intensity and phase retrieval by frequency-resolved optical gating and a computational neural network.

    PubMed

    Krumbügel, M A; Ladera, C L; Delong, K W; Fittinghoff, D N; Sweetser, J N; Trebino, R

    1996-01-15

    Ultrashort-laser-pulse retrieval in frequency-resolved optical gating has previously required an iterative algorithm. Here, however, we show that a computational neural network can directly and rapidly recover the intensity and phase of a pulse.

  2. 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.

  3. Crop Frequency Mapping for Land Use Intensity Estimation During Three Decades

    NASA Astrophysics Data System (ADS)

    Schmidt, Michael; Tindall, Dan

    2016-08-01

    Crop extent and frequency maps are an important input to inform the debate around land value and competitive land uses, food security and sustainability of agricultural practices. Such spatial datasets are likely to support decisions on natural resource management, planning and policy. The complete Landsat Time Series (LTS) archive for 23 Landsat footprints in western Queensland from 1987 to 2015 was used in a multi-temporal mapping approach. Spatial, spectral and temporal information were combined in multiple crop-modelling steps, supported by on ground training data sampled across space and time for the classes Crop and No-Crop. Temporal information within summer and winter growing seasons for each year were summarised, and combined with various vegetation indices and band ratios computed from a mid-season spectral-composite image. All available temporal information was spatially aggregated to the scale of image segments in the mid- season composite for each growing season and used to train a random forest classifier for a Crop and No- Crop classification. Validation revealed that the predictive accuracy varied by growing season and region to be within k = 0.88 to 0.97 and are thus suitable for mapping current and historic cropping activity. Crop frequency maps were produced for all regions at different time intervals. The crop frequency maps were validated separately with a historic crop information time series. Different land use intensities and conversions e.g. from agricultural to pastures are apparent and potential drivers of these conversions are discussed.

  4. 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

  5. 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

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

    PubMed Central

    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.

    2015-01-01

    Abstract. 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

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

    PubMed

    Cheng, Linyin; AghaKouchak, Amir

    2014-11-18

    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.

  8. 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

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

    NASA Astrophysics Data System (ADS)

    Cheng, Linyin; Aghakouchak, Amir

    2014-11-01

    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.

  10. 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

  11. Uncertainty of Intensity-Duration-Frequency (IDF) curves due to varied climate baseline periods

    NASA Astrophysics Data System (ADS)

    Fadhel, Sherien; Rico-Ramirez, Miguel Angel; Han, Dawei

    2017-04-01

    Storm water management systems depend on Intensity-Duration-Frequency (IDF) curves as a standard design tool. However, due to climate change, the extreme precipitation quantiles represented by IDF curves will be subject to alteration over time. Currently, a common approach is to adopt a single benchmark period for bias correction, which is inadequate in deriving reliable future IDF curves. This study assesses the expected changes between the IDF curves of the current climate and those of a projected future climate and the uncertainties associated with such curves. To provide future IDF curves, daily precipitation data simulated by a 1-km regional climate model were temporally bias corrected by using eight reference periods with a fixed length of 30 years and a moving window of 5 years between the cases for the period 1950-2014. Then the bias-corrected data were further disaggregated into ensemble of 5-min series by using an algorithm which combines the Nonparametric Prediction (NPRED) model and the method of fragments (MoF) framework. The algorithm uses the radar data to resample the disaggregated future rainfall fragments conditioned to the daily rainfall and temperature data. The disaggregated data were then aggregated into different durations based on concentration time. The results suggest that uncertainty in the percentage of change in the projected rainfall compared to the rainfall in the current climate varies significantly depending on which of the eight reference periods are used for the bias correction. Both the maximum projection of rainfall intensity and the maximum change in future projections are affected by using different reference periods for different frequencies and durations. Such an important issue has been largely ignored by the engineering community and this study has shown the importance of including the uncertainty of benchmarking periods in bias-correcting future climate projections.

  12. Intensity-Duration-Frequency (IDF) rainfall curves, for data series and climate projection in African cities.

    PubMed

    De Paola, Francesco; Giugni, Maurizio; Topa, Maria Elena; Bucchignani, Edoardo

    2014-01-01

    Changes in the hydrologic cycle due to increase in greenhouse gases cause variations in intensity, duration, and frequency of precipitation events. Quantifying the potential effects of climate change and adapting to them is one way to reduce urban vulnerability. Since rainfall characteristics are often used to design water structures, reviewing and updating rainfall characteristics (i.e., Intensity-Duration-Frequency (IDF) curves) for future climate scenarios is necessary (Reg Environ Change 13(1 Supplement):25-33, 2013). The present study regards the evaluation of the IDF curves for three case studies: Addis Ababa (Ethiopia), Dar Es Salaam (Tanzania) and Douala (Cameroon). Starting from daily rainfall observed data, to define the IDF curves and the extreme values in a smaller time window (10', 30', 1 h, 3 h, 6 h, 12 h), disaggregation techniques of the collected data have been used, in order to generate a synthetic sequence of rainfall, with statistical properties similar to the recorded data. Then, the rainfall pattern of the three test cities was analyzed and IDF curves were evaluated. In order to estimate the contingent influence of climate change on the IDF curves, the described procedure was applied to the climate (rainfall) simulations over the time period 2010-2050, provided by CMCC (Centro Euro-Mediterraneo sui Cambiamenti Climatici). The evaluation of the IDF curves allowed to frame the rainfall evolution of the three case studies, considering initially only historical data, then taking into account the climate projections, in order to verify the changes in rainfall patterns. The same set of data and projections was also used for evaluating the Probable Maximum Precipitation (PMP).

  13. 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

  14. 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

    2009-01-01

    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 Tropical Rainfall Measuring Mission (TRMM) data as a cluster of pixels with an 85-GHz polarization-corrected brightness temperature below 255 K and with an area of at least 64 square kilometers. The study database consisted of convective systems in West Africa from May to September 1998-2007, and in the western Pacific from May to November 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 between 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. Subsetting the database revealed some sensitivity in distribution shape to the size of the sampling area, the length of the sample period, and the 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 either wetter or drier than normal.

  15. Extremely low frequency electromagnetic fields and cancer: the epidemiologic evidence.

    PubMed Central

    Bates, M N

    1991-01-01

    This paper reviews the epidemiologic evidence that low frequency electromagnetic fields generated by alternating current may be a 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. PMID:1821368

  16. 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.

  17. 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).

  18. 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.

  19. [The frequency of cancer in France: Most recent data and trends].

    PubMed

    Ribassin-Majed, Laureen; Le-Teuff, Gwénaël; Hill, Catherine

    2017-01-01

    We present and discuss recent data on the frequency of cancer in France and on cancer survival. In the male population, the incidence of prostate and head and neck cancers diminishes rapidly and the incidence of the other common cancers: lung and colorectal diminishes less markedly; cancer mortality decreases for most sites. In the female population, the incidence of breast cancer diminishes rapidly, the incidence of colorectal and uterus cancers diminish less markedly and the incidence of lung cancer increases very fast: the mortality trends are similar. Cancer survival has improved in the last 16 years but some of the improvements are an artifact induced by overdiagnosis.

  20. 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.

  1. 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.

  2. Optimization of Breast Cancer Treatment by Dynamic Intensity Modulated Electron Radiotherapy

    DTIC Science & Technology

    2006-04-01

    AD_________________ Award Number: DAMD17-01-1-0435 TITLE: Optimization of Breast Cancer Treatment by...Optimization of Breast Cancer Treatment by Dynamic Intensity Modulated Electron Radiotherapy 5b. GRANT NUMBER DAMD17-01-1-0435 5c. PROGRAM ELEMENT

  3. Antibiotic Susceptibility and mecA Frequency in Staphylococcus epidermidis, Isolated From Intensive Care Unit Patients

    PubMed Central

    Najar-Peerayeh, Shahin; Jazayeri Moghadas, Ali; Behmanesh, Mehrdad

    2014-01-01

    Background: Coagulase-negative staphylococci (CoNS), especially Staphylococcus epidermidis, are considered as normal flora of human epithelia and also important opportunistic pathogens for nosocomial infections. S. epidermidis can also act as a reservoir for mecA, responsible for high-level resistance to methicillin and transferring it to S. aureus. Objectives: The aim of this study was to determine the prevalence of S. epidermidis as well as antibiotic susceptibility pattern and mecA prevalence in S. epidermidis isolated from intensive care unit (ICU) patients. Materials and Methods: A cross-sectional study was conducted from September 2010 to September 2011 and 184 coagulase-negative staphylococci were collected from different clinical samples in three hospitals. S. epidermidis was identified by conventional bacteriological tests. Antibiotic susceptibility testing was performed using disk diffusion method. Frequency of mecA was detected by specific PCR. Results: Frequency of S. epidermidis was 34.8%, the most susceptibility was seen to linezolid and vancomycin, and the least susceptibility was seen to tetracycline.Majority of the S. epidermidis isolates carried mecA (92.2%). The most common resistant pattern was trimethoprim-sulfamethoxazole, tetracycline, erythromycin, and methicillin resistance, found in 23.4% of the isolates, followed by resistance to methicillin as the second-most common resistant pattern, observed in 20.3% of the isolates. Conclusions: Frequency of S. epidermidis was significantly lower, compared to other studies. Presence rate of mecA and susceptibility to linezolid and vancomycin did not show significant differences with other investigations, while resistant to trimethoprim-sulfamethoxazole was significantly lower compared to other investigations, and resistance to tetracycline was significantly higher in comparison to other investigations. Presence of methicillin-resistant S. epidermidis in ICU patients, especially in individuals with

  4. Acute toxicity of hypofractionated intensity-modulated radiotherapy for prostate cancer

    PubMed Central

    Drodge, C.S.; Boychak, O.; Patel, S.; Usmani, N.; Amanie, J.; Parliament, M.B.; Murtha, A.; Field, C.; Ghosh, S.; Pervez, N.

    2015-01-01

    Background Dose-escalated hypofractionated radiotherapy (hfrt) using intensity-modulated radiotherapy (imrt), with inclusion of the pelvic lymph nodes (plns), plus androgen suppression therapy (ast) in high-risk prostate cancer patients should improve patient outcomes, but acute toxicity could limit its feasibility. Methods Our single-centre phase ii prospective study enrolled 40 high-risk prostate cancer patients. All patients received hfrt using imrt with daily mega-voltage computed tomography imaging guidance, with 95% of planning target volumes (ptv68 and ptv50) receiving 68 Gy and 50 Gy (respectively) in 25 daily fractions. The boost volume was targeted to the involved plns and the prostate (minus the urethra plus 3 mm and minus 3 mm from adjacent rectal wall) and totalled up to 75 Gy in 25 fractions. Acute toxicity scores were recorded weekly during and 3 months after radiotherapy (rt) administration. Results For the 37 patients who completed rt and the 3-month follow-up, median age was 65.5 years (range: 50–76 years). Disease was organ-confined (T1c–T2c) in 23 patients (62.1%), and node-positive in 5 patients (13.5%). All patients received long-term ast. Maximum acute genitourinary (gu) and gastrointestinal (gi) toxicity peaked at grade 2 in 6 of 36 evaluated patients (16.6%) and in 4 of 31 evaluated patients (12.9%) respectively. Diarrhea and urinary frequency were the chief complaints. Dose–volume parameters demonstrated no correlation with toxicity. The ptv treatment objectives were met in 36 of the 37 patients. Conclusions This hfrt dose-escalation trial in high-risk prostate cancer has demonstrated the feasibility of administering 75 Gy in 25 fractions with minimal acute gi and gu toxicities. Further follow-up will report late toxicities and outcomes. PMID:25908924

  5. 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.

  6. 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

  7. Frequency and intensity of extreme drought in the Delaware Basin, 1600-2002

    NASA Astrophysics Data System (ADS)

    Kauffman, G. J.; Vonck, K. J.

    2011-05-01

    The frequency and severity of drought in the Delaware Basin between 1600 and 2002 are examined using the Palmer Drought Severity Index (PDSI) estimated from tree ring data and correlated with reconstructed annual low flows. In the Delaware Basin, the most severe drought in nearly a century occurred during 1995-2002 as the Brandywine River, Delaware's largest surface water supply, ran dry at its mouth and declined to the lowest flow on record since 1912. To evaluate the long-term context of the 1995-2002 droughts given a variable hydroclimate, tree ring and PDSI data were correlated to reconstruct flows along the river to 1600, the beginning of European exploration to the Delaware Bay. Reconstructed PDSI and low flows were fit using general extreme value (GEV) distributions to estimate drought frequency. Some variability is present as reconstructed low flows tend to overestimate recorded streamflow in severe dry years, a finding reported by others. Some uncertainty appears in the correlations as the coefficient of multiple determination (CRSQ) between recorded and estimated PDSI from tree ring data is 0.50-0.54, a level of variance considered to be "quite good," and the coefficient of determination (r2) between PDSI and low flow is 0.52. Given the uncertainty, PDSI and reconstructed low flow data both agree that the most extreme drought in 400 years occurred during 1635, and the drought of 1995-2000 was historically extreme with differences only in the degree of severity. On the basis of PDSI, the 2002, 1999, and 1995 droughts were the sixth, twelfth, and seventeenth most severe in 400 years with frequencies of once every 50, 33, and 16 years, respectively. Based on low flow, the 2002, 1999, and 1995 droughts were the second, fourth, and ninth most severe since 1600 with frequencies of once every 200, 100, and 50 years, respectively. The record drought of 2002 has a low probability of reoccurring in any given year (2.0% by PDSI and 0.5% by low flow), but droughts

  8. High-Frequency Acoustic Impedance Imaging of Cancer Cells.

    PubMed

    Fadhel, Muhannad N; Berndl, Elizabeth S L; Strohm, Eric M; Kolios, Michael C

    2015-10-01

    Variations in the acoustic impedance throughout cells and tissue can be used to gain insight into cellular microstructures and the physiologic state of the cell. Ultrasound imaging can be used to create a map of the acoustic impedance, on which fluctuations can be used to help identify the dominant ultrasound scattering source in cells, providing information for ultrasound tissue characterization. The physiologic state of a cell can be inferred from the average acoustic impedance values, as many cellular physiologic changes are linked to an alteration in their mechanical properties. A recently proposed method, acoustic impedance imaging, has been used to measure the acoustic impedance maps of biological tissues, but the method has not been used to characterize individual cells. Using this method to image cells can result in more precise acoustic impedance maps of cells than obtained previously using time-resolved acoustic microscopy. We employed an acoustic microscope using a transducer with a center frequency of 375 MHz to calculate the acoustic impedance of normal (MCF-10 A) and cancerous (MCF-7) breast cells. The generated acoustic impedance maps and simulations suggest that the position of the nucleus with respect to the polystyrene substrate may have an effect on the measured acoustic impedance value of the cell. Fluorescence microscopy and confocal microscopy were used to correlate acoustic impedance images with the position of the nucleus within the cell. The average acoustic impedance statistically differed between normal and cancerous breast cells (1.636 ± 0.010 MRayl vs. 1.612 ± 0.006 MRayl), indicating that acoustic impedance could be used to differentiate between normal and cancerous cells.

  9. 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.

  10. Remote excitation of neuronal circuits using low-intensity, low-frequency ultrasound.

    PubMed

    Tyler, William J; Tufail, Yusuf; Finsterwald, Michael; Tauchmann, Monica L; Olson, Emily J; Majestic, Cassondra

    2008-01-01

    Possessing the ability to noninvasively elicit brain circuit activity yields immense experimental and therapeutic power. Most currently employed neurostimulation methods rely on the somewhat invasive use of stimulating electrodes or photon-emitting devices. Due to its ability to noninvasively propagate through bone and other tissues in a focused manner, the implementation of ultrasound (US) represents a compelling alternative approach to current neuromodulation strategies. Here, we investigated the influence of low-intensity, low-frequency ultrasound (LILFU) on neuronal activity. By transmitting US waveforms through hippocampal slice cultures and ex vivo mouse brains, we determined LILFU is capable of remotely and noninvasively exciting neurons and network activity. Our results illustrate that LILFU can stimulate electrical activity in neurons by activating voltage-gated sodium channels, as well as voltage-gated calcium channels. The LILFU-induced changes in neuronal activity were sufficient to trigger SNARE-mediated exocytosis and synaptic transmission in hippocampal circuits. Because LILFU can stimulate electrical activity and calcium signaling in neurons as well as central synaptic transmission we conclude US provides a powerful tool for remotely modulating brain circuit activity.

  11. Development of Sub-Daily Intensity Duration Frequency (IDF) Curves for Major Urban Areas in India

    NASA Astrophysics Data System (ADS)

    Ali, H.; Mishra, V.

    2014-12-01

    Extreme precipitation events disrupt urban transportation and cause enormous damage to infrastructure. Urban areas are fast responding catchments due to significant impervious surface. Stormwater designs based on daily rainfall data provide inadequate information. We, therefore, develop intensity-duration-frequency curves using sub-daily (1 hour to 12 hour) rainfall data for 57 major urban areas in India. While rain gage stations data from urban areas are most suitable, but stations are unevenly distributed and their data have gaps and inconsistencies. Therefore, we used hourly rainfall data from the Modern Era Retrospective-analysis for Research and Applications (MERRA), which provides a long term data (1979 onwards). Since reanalysis products have uncertainty associated with them we need to enhance their accuracy before their application. We compared daily rain gage station data obtained from Global Surface Summary of Day Data (GSOD) available for 65 stations for the period of 2000-2010 with gridded daily rainfall data provided by Indian Meteorological Department (IMD). 3-hourly data from NOAA/Climate Prediction Center morphing technique (CMORPH), Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks (PERSIANN), and the Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis (TMPA) were aggregated to daily for comparison with GSOD station data . TMPA is found to be best correlated with GSOD data. We used TMPA data to correct MERRA's hourly precipitation, which were applied to develop IDF curves. We compared results with IDF curves from empirical methods and found substantial disparities in the existing stormwater designs in India.

  12. 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.

  13. Prevention of Slip-Related Backward Balance Loss: Effect of Session Intensity and Frequency on Long-Term Retention

    PubMed Central

    Bhatt, Tanvi; Pai, Yi-Chung

    2008-01-01

    Objective To examine effects of session intensity (number of slip exposures) and frequency on retention of acquired adaptation for prevention of backward balance loss following repeated-slip training. Setting Biomechanics research laboratory. Participants Healthy young subjects (N=46; 21 males). Intervention Twenty-four subjects experienced a high-intensity session of 24 repeated right-side slips; 12 received additional single-slip sessions at a frequency of 1-week, 2-week, and 1-month, while the rest got no ancillary training. Another 24 subjects received a low-intensity initial session of a single slip; 12 received the same high-frequency ancillary training, while the rest got none. All groups were retested with a single-slip, 4 months after first session. Main Outcome Measures Incidence of backward balance loss, gait stability, and limb support. Results The high-intensity groups irrespective of ancillary training displayed similar improvements in all 3 outcome measures. Remarkably, the low-intensity group receiving ancillary training also significantly improved in all measures, with retention comparable to that observed in the other 2 groups. A single slip exposure without ancillary sessions was insufficient to yield longer-term effect. Conclusions Frequent ancillary sessions may be unnecessary for slip-related fall prevention up to 4 months, if initial session intensity is sufficient. Furthermore, the minimum of a single slip may be as effective, if subject is exposed to frequent ancillary sessions. PMID:19154827

  14. 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.

  15. Positive Prehabilitative Effect of Intense Treadmill Exercise for Ameliorating Cancer Cachexia Symptoms in a Mouse Model

    PubMed Central

    Jee, Hyunseok; Chang, Ji-Eun; Yang, Eun Joo

    2016-01-01

    Due to the importance of exercise in prehabilitation, we conducted this study to understand the effects of different exercise intensities on cancer-related cachexia. Forty adult male CDF1 mice were randomly divided into a non-cancer control group (N=10, NC), cancer control group (N=10, CC), cancer with moderate exercise group (N=10, ME, 70% maxHR), and cancer with intense exercise group (N=10, SE, 90% maxHR) for obtaining data such as tissue weight and body weight changes, quality of life (QoL) indicators, and levels of cytokines and a muscle homeostasis regulatory protein. We verified that mouse colonic carcinoma cancer cells metastasized based on our observation that the weight of CC group lungs was almost 87% greater than NC group lungs. Survival rates of SE, NC, ME, and CC groups were 100%, 100%, 80%, and 50%, respectively (p<0.01). Other results such as tissue and body weight changes, QoL indicators, and protein analyses also supported our hypothesis that the SE group had improved survival compared to CC and ME groups (p<0.05 and p<0.01, respectively). Our results suggest that exercise, especially intense exercise, improves QoL and survival rate and prevents muscle atrophy. These data suggest that exercise is an optimal prehabilitation choice to alleviate the negative impacts of cancer cachexia. PMID:27994677

  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. 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.

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

    PubMed Central

    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/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. PMID:25391603

  19. 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.

  20. Effect of pulse repetition frequency of high-intensity focused ultrasound on in vitro thrombolysis.

    PubMed

    Yang, Wenjing; Zhou, Yufeng

    2017-03-01

    Vascular occlusion by the thrombi is the main reason for ischemic stroke and deep vein thrombosis. High-intensity focused ultrasound (HIFU) and histotripsy or microtripsy pulses can effectively dissolve the blood clot with no use of thrombolytic agent and ultrasound contrast agent (microbubbles). In this study, HIFU bursts at the same duty cycle (2%) but varied pulse repetition frequency (PRF) from 1Hz to 1000Hz were delivered to in vitro porcine blood clot for 30s. Thrombolysis efficiency initially increases slightly with the PRF, 86.4±10.3%, 89.9±11.9, and 92.9±12.8% at the PRF of 1Hz, 10Hz, and 100Hz, respectively, without significant difference (p>0.05), but then drops dramatically to 37.9±6.9% at the PRF of 1000Hz (p<0.05). The particle size in the supernatant of dissolution is 547.1±129.5nm, which suggests the disruption of thrombi into the subcellular level. Thrombi motion during HIFU exposure shows violent motion and significant curling at the low PRF, rotation about its axis with occasional curling at the moderate PRF, and localized vibration at the high PRF due to the generation of acoustic radiation force and streaming. Quantitative analysis of recorded motion shows the axial displacement decreases with the PRF of delivered HIFU bursts, from 3.9±1.5mm at 1Hz to 0.7±0.4mm at 1000Hz. Bubble cavitation during HIFU exposure to the blood clot was also monitored. The increase of PRF led to the increase of inertial cavitation but the decrease of stable cavitation. In summary, the PRF of delivered HIFU bursts at the same output energy has a significant effect on the thrombi motion, bubble cavitation activities, and subsequently thrombolysis efficiencies.

  1. What are the best covariates for developing non-stationary rainfall Intensity-Duration-Frequency relationship?

    NASA Astrophysics Data System (ADS)

    Agilan, V.; Umamahesh, N. V.

    2017-03-01

    Present infrastructure design is primarily based on rainfall Intensity-Duration-Frequency (IDF) curves with so-called stationary assumption. However, in recent years, the extreme precipitation events are increasing due to global climate change and creating non-stationarity in the series. Based on recent theoretical developments in the Extreme Value Theory (EVT), recent studies proposed a methodology for developing non-stationary rainfall IDF curve by incorporating trend in the parameters of the Generalized Extreme Value (GEV) distribution using Time covariate. But, the covariate Time may not be the best covariate and it is important to analyze all possible covariates and find the best covariate to model non-stationarity. In this study, five physical processes, namely, urbanization, local temperature changes, global warming, El Niño-Southern Oscillation (ENSO) cycle and Indian Ocean Dipole (IOD) are used as covariates. Based on these five covariates and their possible combinations, sixty-two non-stationary GEV models are constructed. In addition, two non-stationary GEV models based on Time covariate and one stationary GEV model are also constructed. The best model for each duration rainfall series is chosen based on the corrected Akaike Information Criterion (AICc). From the findings of this study, it is observed that the local processes (i.e., Urbanization, local temperature changes) are the best covariate for short duration rainfall and global processes (i.e., Global warming, ENSO cycle and IOD) are the best covariate for the long duration rainfall of the Hyderabad city, India. Furthermore, the covariate Time is never qualified as the best covariate. In addition, the identified best covariates are further used to develop non-stationary rainfall IDF curves of the Hyderabad city. The proposed methodology can be applied to other situations to develop the non-stationary IDF curves based on the best covariate.

  2. 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.

  3. Critically ill patients with cancer: chances and limitations of intensive care medicine—a narrative review

    PubMed Central

    Schellongowski, Peter; Sperr, Wolfgang R; Wohlfarth, Philipp; Knoebl, Paul; Rabitsch, Werner; Watzke, Herbert H; Staudinger, Thomas

    2016-01-01

    This narrative review deals with the challenge of defining adequate therapy goals and intensive care unit (ICU) admission criteria for critically ill patients with cancer. Several specific complications of critically ill patients with cancer require close collaborations of intensive care and cancer specialists. Intensivists require a basic understanding of the pathophysiology, diagnosis and therapy of common cancer-specific problems. Cancer specialists must be knowledgeable in preventing, detecting and treating imminent or manifest organ failures. In case of one or more organ dysfunctions, ICU admissions must be evaluated early. In order to properly define the therapy goals for critically ill patients with cancer, decision-makers must be aware of the short-term intensive care prognosis as well as the long-term oncological options and perspectives. Multidisciplinary teamwork is key when it comes down to decisions on ICU admission, planning of therapeutic aims, patient management in the ICU and tailored therapy limiting with smooth transition into a palliative care (PC) setting, whenever appropriate. PMID:27843637

  4. 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

  5. Radio frequency electromagnetic fields: cancer, mutagenesis, and genotoxicity.

    PubMed

    Heynick, Louis N; Johnston, Sheila A; Mason, Patrick A

    2003-01-01

    We present critiques of epidemiologic studies and experimental investigations, published mostly in peer-reviewed journals, on cancer and related effects from exposure to nonionizing electromagnetic fields in the nominal frequency range of 3 kHz to 300 GHz of interest to Subcommittee 4 (SC4) of the International Committee on Electromagnetic Safety (ICES). The major topics discussed are presented under the headings Epidemiologic and Other Findings on Human Exposure, Mammals Exposed In Vivo, Mammalian Live Tissues and Cell Preparations Exposed In Vitro, and Mutagenesis and Genotoxicity in Microorganisms and Fruit Flies. Under each major topic, we present minireviews of papers on various specific endpoints investigated. The section on Epidemiologic and Other Findings on Human Exposure is divided into two subsections, the first on possible carcinogenic effects of exposure from emitters not in physical contact with the populations studied, for example, transmitting antennas and other devices. Discussed in the second subsection are studies of postulated carcinogenic effects from use of mobile phones, with prominence given to brain tumors from use of cellular and cordless telephones in direct physical contact with an ear of each subject. In both subsections, some investigations yielded positive findings, others had negative findings, including papers directed toward experimentally verifying positive findings, and both were reported in a few instances. Further research on various important aspects may resolve such differences. Overall, however, the preponderance of published epidemiologic and experimental findings do not support the supposition that in vivo or in vitro exposures to such fields are carcinogenic.

  6. 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.

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. Influence of different breathing frequencies on the severity of inspiratory muscle fatigue induced by high-intensity front crawl swimming.

    PubMed

    Jakovljevic, Djordje G; McConnell, Alison K

    2009-07-01

    The aim of the present study was to assess the influence of 2 different breathing frequencies on the magnitude of inspiratory muscle fatigue after high-intensity front crawl swimming. The influence of different breathing frequencies on postexercise blood lactate ([La]) and heart rate (HR) was also examined. Ten collegiate swimmers performed 2 x 200-m front crawl swims at 90% of race pace with the following breathing frequencies: 1) 1 breath every second stroke (B2), and 2) 1 breath every fourth stroke (B4). Maximal inspiratory pressure (PImax) was measured at the mouth from residual volume before (baseline) and after swimming, in a standing position. The HR and [La] were assessed at rest and immediately at the cessation of swimming. The PImax decreased by 21% after B4 and by 11% after B2 compared with baseline (p < 0.05). The [La] was lower by 15% after B4 than after B2 (p < 0.05). The HR was not significantly different between B2 and B4. These data suggest that there is significant global inspiratory muscle fatigue after high-intensity swimming. Inspiratory muscle fatigue is, however, greater when breathing frequency is reduced during high-intensity front crawl swimming. Respiratory muscle training should be used to improve respiratory muscle strength and endurance in swimmers.

  12. Backwash intensity and frequency impact the microbial community structure and function in a fixed-bed biofilm reactor.

    PubMed

    Li, Xu; Yuen, Wangki; Morgenroth, Eberhard; Raskin, Lutgarde

    2012-11-01

    Linkages among bioreactor operation and performance and microbial community structure were investigated for a fixed-bed biofilm system designed to remove perchlorate from drinking water. Perchlorate removal was monitored to evaluate reactor performance during and after the frequency and intensity of the backwash procedure were changed, while the microbial community structure was studied using clone libraries and quantitative PCR targeting the 16S rRNA gene. When backwash frequency was increased from once per month to once per day, perchlorate removal initially deteriorated and then recovered, and the relative abundance of perchlorate-reducing bacteria (PRB) initially increased and then decreased. This apparent discrepancy suggested that bacterial populations other than PRB played an indirect role in perchlorate removal, likely by consuming dissolved oxygen, a competing electron acceptor. When backwash intensity was increased, the reactor gradually lost its ability to remove perchlorate, and concurrently the relative abundance of PRB decreased. The results indicated that changes in reactor operation had a profound impact on reactor performance through altering the microbial community structure. Backwashing is an important yet poorly characterized procedure when operating fixed-bed biofilm reactors. Compared to backwash intensity, changes in backwash frequency exerted less disturbance on the microbial community in the current study. If this finding can be confirmed in future work, backwash frequency may serve as the primary parameter when optimizing backwash procedures.

  13. 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.

  14. [Intensity-modulated radiotherapy in head and neck cancer: ethics and methodology].

    PubMed

    Lapeyre, M; Biau, J; Miroir, J; Servagi-Vernat, S; Giraud, P

    2014-10-01

    Numerous studies have shown that intensity-modulated radiation therapy is the standard technique for the radiation treatment of head and neck cancers. Intensity-modulated radiation therapy reduces side effects (xerostomia, dysphagia, fibrosis, etc.) and improves the results for cancer localizations with highly complex shapes such as the cavum or nasal cavity. Intensity-modulated radiation therapy is also a costly technique that necessitates a numerous staff, highly trained, with regular practice. If this technique cannot be available (understaffing, overwork, etc.) the choice between entrusting the patient to a colleague and treating the patient with a less sophisticated technique such as 3-dimensional conformal radiation therapy depends on different objective and ethical criteria.

  15. Influence of high intensity focused ultrasound (HIFU) treatment to the pancreatic function in pancreatic cancer patients.

    PubMed

    Shi, Yulan; Ying, Xiao; Hu, Xiaoye; Zhao, Jing; Fang, Xuefeng; Wu, Minghui; Chen, Tian Zhou; Shen, Hong

    2015-05-01

    Present study was designed to investigate the pancreatic endocrine and exocrine function damage after High Intensity Focused Ultrasound (HIFU) therapy in patients with advanced pancreatic cancer. It was a retrospective analysis of blood glucose and amylase changes in 59 advanced pancreatic cancer patients treated with HIFU from 2010 February to 2014 January. The mean glucose and amylase before HIFU treatment were 6.02mmol/L and 59.17 U/L respectively. After HIFU treatment, it was shown that the mean glucose and amylase levels were 5.66mmol/L and 57.86/L respectively. There was no statistical significance between them. No acute pancreatitis was observed. The endocrine and exocrine function of pancreatic cancer patients was not damaged by HIFU treatment. HIFU treatment for the pancreatic cancer patients seems to be safe.

  16. 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.

  17. Proactive nurse management guidelines for managing intensive chemotherapy regimens in patients with advanced gastric cancer.

    PubMed

    Baker, J; Ajani, J A

    2008-07-01

    Patients with advanced gastric cancer have a poor prognosis. Intensive chemotherapy regimens may be effective for the treatment of this disease but may be associated with a significant number of severe adverse events. Optimal management of these adverse events can improve outcome for the patient. Currently, there is little information in the literature about the nursing management of this particular group of patients. This American study involved the nursing management of all patients with gastric or gastroesophageal cancer enrolled in clinical trials at a single center. Patients had close contact with research nurses and received education about adverse events and how to deal with them. Patients completed a detailed treatment diary for each cycle of treatment. Protocols were established for the management of emergent adverse events. The guidelines developed during this study could help to underpin the role of the specialist oncology nurse and improve the management of patients undergoing intensive chemotherapy for gastric and gastroesophageal cancer, with the potential of improving outcome, or at least quality of life, for the patients. The nurses' role should be pivotal in the management of intensive chemotherapy for gastric and gastroesophageal cancer.

  18. Pain Intensity and Pain Interference in patients with lung cancer: A pilot study of Biopsychosocial Predictors

    PubMed Central

    Dalton, Jo Ann; Higgins, Melinda K.; Miller, Andrew H.; Keefe, Francis J.; Khuri, Fadlo R.

    2013-01-01

    Objective To explore biopsychosocial factors (beliefs, depression, catastrophizing cytokines) in individuals newly diagnosed with lung cancer and no pain in order to determine their relationship at diagnosis and across time and to determine whether these factors contribute to pain intensity or pain interference with function at pain onset. Methods A longitudinal, exploratory, pilot study was implemented in a private medical center and a VA medical center in the southeast. Twelve subjects not experiencing pain related to cancer of the lung or its treatment were recruited. A Karnofsky status of 40% and Hemoglobin of 8 grams were required. Five questionnaires were completed and 10 cc of blood was drawn at Baseline; 4 questionnaires and blood draws were repeated monthly for 5 months. One Baseline questionnaire and a pain assessment were added at Final. Demographic, clinical and questionnaire data were summarized; standardized scale scores were calculated. Results Biopsychosocial scores that were low at Baseline increased from T1-T4 but decreased slightly T5-T6. Individuals with higher pain intensity and higher pain interference at Final had higher psychosocial scores at Baseline than individuals with lower pain intensity and lower pain interference at Final. Conclusions Unrelated to disease stage, metastasis or treatment, unique, levels of biopsychosocial factors are observed in patients newly diagnosed with lung cancer who report higher levels of Pain Intensity and higher levels of Pain Interference at the time pain occurs. Replication studies are needed to validate this response pattern and determine the value of repeated individual assessments. PMID:24064756

  19. Influence of intensity and frequency of ultrasonic waves on capillary interaction and oil recovery from different rock types.

    PubMed

    Naderi, Khosrow; Babadagli, Tayfun

    2010-03-01

    Oil saturated cylindrical sandstone cores were placed into imbibition cells where they contacted with an aqueous phase and oil recovery performances were tested with and without ultrasonic radiation keeping all other conditions and parameters constant. Experiments were conducted for different initial water saturation, oil viscosity and wettability. The specifications of acoustic sources such as ultrasonic intensity (45-84W/sqcm) and frequency (22 and 40kHz) were also changed. An increase in recovery was observed with ultrasonic energy in all cases. This change was more remarkable for the oil-wet medium. The additional recovery with ultrasonic energy became lower as the oil viscosity increased. We also designed a setup to measure the ultrasonic energy penetration capacity in different media, namely air, water, and slurry (sand+water mixture). A one-meter long water or slurry filled medium was prepared and the ultrasonic intensity and frequency were monitored as a function of distance from the source. The imbibition cells were placed at certain distances from the sources and the oil recovery was recorded. Then, the imbibition recovery was related to the ultrasonic intensity, frequency, and distance from the ultrasonic source.

  20. 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.

  1. 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

  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

    1989-01-01

    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. 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.

  4. [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.

  5. Low intensity electromagnetic irradiation with 70.6 and 73 GHz frequencies affects Escherichia coli growth and changes water properties.

    PubMed

    Torgomyan, Heghine; Kalantaryan, Vitaly; Trchounian, Armen

    2011-07-01

    The low intensity electromagnetic irradiation (EMI) of the 70.6 and 73 GHz frequency is resonant for Escherichia coli but not for water. In this study, E. coli irradiation with this EMI during 1 h directly and in bi-distilled water or in the assay buffer with those frequencies resulted with noticeable changes in bacterial growth parameters. Furthermore, after EMI, 2 h rest of bacteria renewed their growth in 1.2-fold, but repeated EMI--had no significant action. Moreover, water absorbance, pH, and electric conductance were changed markedly after such irradiation. The results point out that EMI of the 70.6 and 73 GHz frequency can interact with bacteria affecting growth and in the same time with the surrounding medium (water) as well.

  6. 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...

  7. 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.…

  8. Topographic distribution, frequency, and intensity dependence of stimulus-specific adaptation in the inferior colliculus of the rat.

    PubMed

    Duque, Daniel; Pérez-González, David; Ayala, Yaneri A; Palmer, Alan R; Malmierca, Manuel S

    2012-12-05

    The ability to detect unexpected sounds within the environment is an important function of the auditory system, as a rapid response may be required for the organism to survive. Previous studies found a decreased response to repetitive stimuli (standard), but an increased response to rare or less frequent sounds (deviant) in individual neurons in the inferior colliculus (IC) and at higher levels. This phenomenon, known as stimulus-specific adaptation (SSA) has been suggested to underpin change detection. Currently, it is not known how SSA varies within a single neuron receptive field, i.e., it is unclear whether SSA is a unique property of the neuron or a feature that is frequency and/or intensity dependent. In the present experiments, we used the common SSA index (CSI) to quantify and compare the degree of SSA under different stimulation conditions in the IC of the rat. We calculated the CSI at different intensities and frequencies for each individual IC neuron to map the neuronal CSI within the receptive field. Our data show that high SSA is biased toward the high-frequency and low-intensity regions of the receptive field. We also find that SSA is better represented in the earliest portions of the response, and there is a positive correlation between the width of the frequency response area of the neuron and the maximum level of SSA. The present data suggest that SSA in the IC is not mediated by the intrinsic membrane properties of the neurons and instead might be related to an excitatory and/or inhibitory input segregation.

  9. 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.

  10. Midbrain Frequency Representation following Moderately Intense Neonatal Sound Exposure in a Precocious Animal Model (Chinchilla laniger)

    PubMed Central

    2016-01-01

    Auditory brain areas undergo reorganization resulting from abnormal sensory input during early postnatal development. This is evident from studies at the cortical level but it remains unclear whether there is reorganization in the auditory midbrain in a species similar to the human, that is, with early hearing onset. We have explored midbrain plasticity in the chinchilla, a precocious species that matches the human in terms of hearing development. Neonatal chinchillas were chronically exposed to a 2 kHz narrowband sound at 70 dB SPL for 4 weeks. Tonotopic maps in inferior colliculus (central nucleus) were defined based on single neuron characteristic frequency. We hypothesized an overrepresentation of the 2 kHz region of the maps. However, we observed a significant decrease in the proportion of neurons dedicated to the 2 kHz octave band and also away from the exposure frequency at 8 kHz. In addition, we report a significant increase in low frequency representation (<1 kHz), again a change to tonotopic mapping distant to the 2 kHz region. Thus in a precocious species, tonotopic maps in auditory midbrain are altered following abnormal stimulation during development. However, these changes are more complex than the overrepresentation of exposure related frequency regions that are often reported. PMID:27895941

  11. Super-resolution imaging using the spatial-frequency filtered intensity fluctuation correlation

    NASA Astrophysics Data System (ADS)

    Sprigg, Jane; Peng, Tao; Shih, Yanhua

    2016-12-01

    We report an experimental demonstration of a nonclassical imaging mechanism with super-resolving power beyond the Rayleigh limit. When the classical image is completely blurred out due to the use of a small imaging lens, by taking advantage of the intensity fluctuation correlation of thermal light, the demonstrated camera recovered the image of the resolution testing gauge. This method could be adapted to long distance imaging, such as satellite imaging, which requires large diameter camera lenses to achieve high image resolution.

  12. 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.

  13. 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

  14. 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.

  15. Prostate Cancer and Ambient Pesticide Exposure in Agriculturally Intensive Areas in California

    PubMed Central

    Cockburn, Myles; Mills, Paul; Zhang, Xinbo; Zadnick, John; Goldberg, Dan; Ritz, Beate

    2011-01-01

    In a population-based case-control study in California's intensely agricultural Central Valley (2005–2006), the authors investigated relations between environmental pesticide/fungicide exposure and prostate cancer. Cases (n = 173) were obtained from a population-based cancer registry, and controls (n = 162) were obtained from Medicare listings and tax assessor mailings. Past ambient exposures to pesticides/fungicides were derived from residential history and independently recorded pesticide and land-use data, using a novel geographic information systems approach. In comparison with unexposed persons, increased risks of prostate cancer were observed among persons exposed to compounds which may have prostate-specific biologic effects (methyl bromide (odds ratio = 1.62, 95% confidence interval: 1.02, 2.59) and a group of organochlorines (odds ratio = 1.64, 95% confidence interval: 1.02, 2.63)) but not among those exposed to other compounds that were included as controls (simazine, maneb, and paraquat dichloride). The authors assessed the possibility of selection bias due to less-than-100% enrollment of eligible cases and controls (a critical methodological concern in studies of this kind) and determined that there was little evidence of bias affecting the estimated effect size. This study provides evidence of an association between prostate cancer and ambient pesticide exposures in and around homes in intensely agricultural areas. The associations appear specific to compounds with a plausible biologic role in prostate carcinogenesis. PMID:21447478

  16. Targeted treatment of cancer with radiofrequency electromagnetic fields amplitude-modulated at tumor-specific frequencies.

    PubMed

    Zimmerman, Jacquelyn W; Jimenez, Hugo; Pennison, Michael J; Brezovich, Ivan; Morgan, Desiree; Mudry, Albert; Costa, Frederico P; Barbault, Alexandre; Pasche, Boris

    2013-11-01

    In the past century, there have been many attempts to treat cancer with low levels of electric and magnetic fields. We have developed noninvasive biofeedback examination devices and techniques and discovered that patients with the same tumor type exhibit biofeedback responses to the same, precise frequencies. Intrabuccal administration of 27.12 MHz radiofrequency (RF) electromagnetic fields (EMF), which are amplitude-modulated at tumor-specific frequencies, results in long-term objective responses in patients with cancer and is not associated with any significant adverse effects. Intrabuccal administration allows for therapeutic delivery of very low and safe levels of EMF throughout the body as exemplified by responses observed in the femur, liver, adrenal glands, and lungs. In vitro studies have demonstrated that tumor-specific frequencies identified in patients with various forms of cancer are capable of blocking the growth of tumor cells in a tissue- and tumor-specific fashion. Current experimental evidence suggests that tumor-specific modulation frequencies regulate the expression of genes involved in migration and invasion and disrupt the mitotic spindle. This novel targeted treatment approach is emerging as an appealing therapeutic option for patients with advanced cancer given its excellent tolerability. Dissection of the molecular mechanisms accounting for the anti-cancer effects of tumor-specific modulation frequencies is likely to lead to the discovery of novel pathways in cancer.

  17. Targeted treatment of cancer with radiofrequency electromagnetic fields amplitude-modulated at tumor-specific frequencies

    PubMed Central

    Zimmerman, Jacquelyn W.; Jimenez, Hugo; Pennison, Michael J.; Brezovich, Ivan; Morgan, Desiree; Mudry, Albert; Costa, Frederico P.; Barbault, Alexandre; Pasche, Boris

    2013-01-01

    In the past century, there have been many attempts to treat cancer with low levels of electric and magnetic fields. We have developed noninvasive biofeedback examination devices and techniques and discovered that patients with the same tumor type exhibit biofeedback responses to the same, precise frequencies. Intrabuccal administration of 27.12 MHz radiofrequency (RF) electromagnetic fields (EMF), which are amplitude-modulated at tumor-specific frequencies, results in long-term objective responses in patients with cancer and is not associated with any significant adverse effects. Intrabuccal administration allows for therapeutic delivery of very low and safe levels of EMF throughout the body as exemplified by responses observed in the femur, liver, adrenal glands, and lungs. In vitro studies have demonstrated that tumor-specific frequencies identified in patients with various forms of cancer are capable of blocking the growth of tumor cells in a tissue- and tumor-specific fashion. Current experimental evidence suggests that tumor-specific modulation frequencies regulate the expression of genes involved in migration and invasion and disrupt the mitotic spindle. This novel targeted treatment approach is emerging as an appealing therapeutic option for patients with advanced cancer given its excellent tolerability. Dissection of the molecular mechanisms accounting for the anti-cancer effects of tumor-specific modulation frequencies is likely to lead to the discovery of novel pathways in cancer. PMID:24206915

  18. Basic study on pulse-intensity-domain depth-controlled photodynamic therapy for transurethral prostate cancer

    NASA Astrophysics Data System (ADS)

    Ohmori, Sayaka; Masuda, Kensuke; Yamakawa, Yuko; Arai, Tsunenori

    2006-02-01

    Photodynamic therapy (PDT) is promising modality for cancer. Prostate cancer is the most common cancer in USA. We proposed transurethral prostate cancer treatment using the pulse-intensity-domain depth-controlled PDT to preserve urethra wall. We have found that photocytotoxicity has been suppressed under high-intensity pulsed excitation with the second generation photosensitizers. We aim to apply this effect to form intact portion on the surface of the irradiated field. Irradiation condition dependence of photocytotoxicity of rat prostate cancer cell line R3327-AT-1 was investigated with two clinical photosensitizers, Porfimer sodium and Talaporfin sodium. A pulsed laser was irradiated with the power energy density ranging from 1.25 to 10 mJ/cm2. Near-infrared luminescence from singlet oxygen in the solution of those two photosensitizers was measured transiently. We performed PDT against a rat subcutaneous prostate tumor mode with Talaporfin sodium (2mg/kg) injected intravenously 1 h prior to the irradiation. The laser was irradiated with the power energy density 2.5 or 10 mW/cm2, with the total fluence of 50 J/cm2. Photocytotoxicity in vitro and the singlet oxygen generation were both suppressed with the 10mJ/cm2 irradiation with Talaporfin sodium, while these with Porfimer sodium were kept relatively constant. The surface of the irradiated field of 1mm in thickness remained intact, while the tumor damaged layer of 1.3 mm in thickness was obtained in the case of 10mJ/cm2 irradiation. We think Talaporfin sodium has high sensitivity to the pulse energy density, which might be useful to realize urethra preserved PDT for prostate cancer.

  19. 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.

  20. Super-resolution imaging using the spatial-frequency filtered intensity fluctuation correlation

    PubMed Central

    Sprigg, Jane; Peng, Tao; Shih, Yanhua

    2016-01-01

    We report an experimental demonstration of a nonclassical imaging mechanism with super-resolving power beyond the Rayleigh limit. When the classical image is completely blurred out due to the use of a small imaging lens, by taking advantage of the intensity fluctuation correlation of thermal light, the demonstrated camera recovered the image of the resolution testing gauge. This method could be adapted to long distance imaging, such as satellite imaging, which requires large diameter camera lenses to achieve high image resolution. PMID:27905498

  1. 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.

  2. Time Evolution of low-Frequency Periodicities in Cosmic ray Intensity

    NASA Astrophysics Data System (ADS)

    Kudela, K.; Rybák, J.; Antalová, A.; Storini, M.

    2002-01-01

    The long-time series of daily means of cosmic-ray intensity observed by four neutron monitors at different cutoff rigidities (Calgary, Climax, Lomnický Štít and Huancayo/Haleakala) were analyzed by means of the wavelet transform method in the period range ~60 to ~1000 days. The contributions of the time evolution of three quasi-periodic cosmic-ray signals (~150 d, ~1.3 yr and ~1.7 yr) to the global one are obtained. While the ~1.7-yr quasi-periodicity, the most remarkable one in the studied interval, strongly contributes to the cosmic ray intensity profile of solar cycle 21 (particularly in 1982), the ~1.3-yr one, which is better correlated with the same periodicity of the interplanetary magnetic field strength, is present as a characteristic feature for the decreasing phases of the cycles 20 and 22. Transitions between these quasi-periodicities are seen in the wavelet power spectra plots. Obtained results support the claimed difference in the solar activity evolution during odd and even solar activity cycles.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Correlation between HLA-A2 gene frequency, latitude, ovarian and prostate cancer mortality rates.

    PubMed

    De Petris, Luigi; Bergfeldt, Kjell; Hising, Christina; Lundqvist, Andreas; Tholander, Bengt; Pisa, Pavel; van der Zanden, Henk G M; Masucci, Giuseppe

    2004-01-01

    Molecular-target therapies are novel approaches to the treatment of prostate and ovarian cancer, but to ensure the best response, a very careful selection of patients, based on immunological characteristics, must be performed. We screened for HLA type, 24 patients with advanced ovarian cancer and 26 patients with hormone-refractory prostate cancer, in order to be recruited to vaccine protocols. HLA typing was performed with PCR in ovarian cancer patients and with serological assay in prostate cancer patients. The results were then extended to a population level, comparing the HLA genotype frequencies in Europe with ovarian and prostate cancer mortality rates. An overrepresentation of HLA-A2 phenotype was observed in both patient groups compared to the normal Swedish population (p = 0.01). As it is already known, the higher phenotype frequency of this allele found in Scandinavian countries decreases significantly as one moves further south in Europe. Ovarian and prostate cancer mortality rates decrease as well as the demographic changes in HLA-A2. These observations have to be confirmed by more extended investigations in order to elucidate if HLA-A2 higher frequency is already present at the diagnosis (risk factor) or is selected during the course of the disease (prognostic factor). Moreover, this fact would suggest different strategies for specific immunotherapy in addition to first line conventional treatments.

  8. Backreflection diagnostics for ultra-intense laser plasma experiments based on frequency resolved optical gating

    NASA Astrophysics Data System (ADS)

    Wagner, F.; Hornung, J.; Schmidt, C.; Eckhardt, M.; Roth, M.; Stöhlker, T.; Bagnoud, V.

    2017-02-01

    We report on the development and implementation of a time resolved backscatter diagnostics for high power laser plasma experiments at the petawatt-class laser facility PHELIX. Pulses that are backscattered or reflected from overcritical plasmas are characterized spectrally and temporally resolved using a specially designed second harmonic generation frequency resolved optical gating system. The diagnostics meets the requirements made by typical experiments, i.e., a spectral bandwidth of more than 30 nm with sub-nanometer resolution and a temporal window of 10 ps with 50 fs temporal resolution. The diagnostics is permanently installed at the PHELIX target area and can be used to study effects such as laser-hole boring or relativistic self-phase-modulation which are important features of laser-driven particle acceleration experiments.

  9. Intense THz pulses down-regulate genes associated with skin cancer and psoriasis: a new therapeutic avenue?

    PubMed Central

    Titova, Lyubov V.; Ayesheshim, Ayesheshim K.; Golubov, Andrey; Rodriguez-Juarez, Rocio; Woycicki, Rafal; Hegmann, Frank A.; Kovalchuk, Olga

    2013-01-01

    Terahertz (THz) radiation lies between the infrared and microwave regions of the electromagnetic spectrum and is non-ionizing. We show that exposure of artificial human skin tissue to intense, picosecond-duration THz pulses affects expression levels of numerous genes associated with non-melanoma skin cancers, psoriasis and atopic dermatitis. Genes affected by intense THz pulses include nearly half of the epidermal differentiation complex (EDC) members. EDC genes, which are mapped to the chromosomal human region 1q21, encode for proteins that partake in epidermal differentiation and are often overexpressed in conditions such as psoriasis and skin cancer. In nearly all the genes differentially expressed by exposure to intense THz pulses, the induced changes in transcription levels are opposite to disease-related changes. The ability of intense THz pulses to cause concerted favorable changes in the expression of multiple genes implicated in inflammatory skin diseases and skin cancers suggests potential therapeutic applications of intense THz pulses. PMID:23917523

  10. Effect of venous dexamethasone, oral caffeine and acetaminophen on relative frequency and intensity of postdural puncture headache after spinal anesthesia

    PubMed Central

    Masoudifar, Mehrdad; Aghadavoudi, Omid; Adib, Sajjad

    2016-01-01

    Background: Postdural puncture headache (PDPH) is a relatively common complication after regional anesthesia, especially in younger people, bothersome to patients and needs prophylaxis to prevent this complication. This study was conducted aiming to determine the preventive effect of dexamethasone plus caffeine and acetaminophen on relative frequency and intensity of PDPH after spinal anesthesia. Materials and Methods: In a clinical trial study, 90 candidates for the lower extremities orthopedic elective operation were divided into two groups of 45 individuals each. Intervention group received the compound of 500 mg acetaminophen +65 mg oral caffeine +8 mg venous dexamethasone an hour before spinal blocking, and the control group received placebo tablets + a dexamethasone equivalent volume of venous normal saline. The level of postoperative headache at the time of entrance to recovery and discharge, 6, 12, 24, 48, and 72 h postoperatively were measured based on Visual Analog Scale criterion in the two groups and then compared with each other. Results: During the study, 24 patients in the control group and 17 patients in the intervention group were afflicted with headache; however, with no significant difference (P = 0.14). Total frequency of headache incidence was 35 times in the control group and 27 times in the intervention group (P = 0.32). Conclusions: Though the taking of acetaminophen + caffeine + dexamethasone is associated with a decrease in headache intensity and duration and decrease in PDPH incidence, compared with placebo, however, no essentially and statistically significant effect was produced. PMID:27169097

  11. The frequency of painful procedures in neonatal intensive care units in South Korea.

    PubMed

    Jeong, Ihn Sook; Park, Soon Mi; Lee, Jeon Ma; Choi, Yoon Jin; Lee, Joohyun

    2014-08-01

    This study was to evaluate the performed painful procedures among all sick neonates cared for at two university hospital neonatal intensive care units (NICUs) in the Republic of Korea. This prospective study was done with all newborns admitted to the NICUs between 1 October and 20 November 2010. Data collection was done with self-administered questionnaire by each nurse for the first 2 weeks of admission and discontinued if the neonate was discharged, transferred or died. The number of painful procedures, according to general characteristics of the neonates, were compared using Mann-Whitney U-test and Kruskal-Wallis test. Oral suctioning was the most frequently performed procedure, followed by tracheal suctioning and nasal suctioning. The number of painful procedures increased as the gestation period became shorter and birthweight decreased. In conclusion, nurses should reappraise the need for painful procedures, in particular, among neonates with a gestation period of ≤ 27 weeks and babies with ≤ 1000 g of birthweight, and execute their performance only if necessary.

  12. 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.

  13. Effects of different intensities of extremely low frequency pulsed electromagnetic fields on formation of osteoclast-like cells.

    PubMed

    Chang, Kyle; Chang, Walter Hong-Shong; Wu, Mei-Ling; Shih, Chung

    2003-09-01

    Over the past 30 years, the beneficial therapeutic effects of selected low energy, time varying electromagnetic fields (EMF) have been documented with increasing frequency to treat therapeutically resistant problems of the musculoskeletal system. However, the underlying mechanisms at a cellular level are still not completely understood. In this study, the effects of extremely low frequency pulsed electromagnetic fields (ELF-PEMF) on osteoclastogenesis, cultured from murine bone marrow cells and stimulated by 1,25(OH)(2)D(3), were examined. Primary bone marrow cells were cultured from mature Wistar rats and exposed to ELF-PEMF stimulation daily for 7 days with different intensities of induced electric field (4.8, 8.7, and 12.2 micro V/cm rms) and stimulation times (0.5, 2, and 8 h/day). Recruitment and authentication of osteoclast-like cells were evaluated, respectively, by determining multinuclear, tartrate resistant acid phosphatase (TRAP) positive cells on day 8 of culture and by the pit formation assay. During the experiments, cytokines such as tumor necrosis factor-alpha (TNF-alpha), interleukin 1-beta (IL-1beta), and prostaglandin-E(2) (PGE(2)) were assayed using the enzyme linked immunosorbent assay (ELISA). These findings suggest that ELF-PEMF can both enhance (approximately 50%) and suppress (approximately 27%) the formation of osteoclast-like cells in bone marrow culture, depending on the induced electric field intensity. In addition, consistent correlations were observed between TNF-alpha, IL-1beta, and osteoclast-like cell number after exposure to different induced electric field intensities of ELF-PEMF. This in vitro study could be considered as groundwork for in vivo ELF-PEMF clinical applications on some osteoclast-associated bone diseases.

  14. Simulation of the Generation of Low Frequency Radiation From Argon Clusters lluminated by High-Intensity Short Pulse Lasers

    NASA Astrophysics Data System (ADS)

    Cordova, Clay

    2005-10-01

    The interaction of high-powered lasers with small plasma clusters is of interest due to its range of applications including the generation of fast ions and electrons for advanced accelerators, self-focusing phenomenon in optics, and production of x-ray and extreme ultraviolet (EUV) radiation. We simulate the interaction of high-intensity lasers with solid density clusters using the fully electromagnetic PIC code TurboWAVE^2. We analyze a range of cluster sizes, laser intensities, and pulse durations to investigate the dependence of low frequency radiation production on these parameters. In this poster, we illustrate the results of this study. In particular, we present calculations of the energy absorbed and released from the cluster, as well as an analysis of the far-field radiation distribution, intensity, and power spectrum. Finally, we present conclusions that may guide future simulations and experiments. 1. ccor@lanl.gov 2. D. Gordon et al. IEEE TRANSACTIONS ON PLASMA SCIENCE, 28 (4), 8/2000, 1135

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

    PubMed

    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.

  16. 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.

  17. Multi-model assessment of potential changes in Intensity-Duration-Frequency curves over Canada

    NASA Astrophysics Data System (ADS)

    Rasmussen, P. F.

    2013-12-01

    Climate change is expected to modify precipitation patterns across the globe, but there are considerable differences between climate models in their projections of change amplitude for individual locations. Most climate change studies focus on changes in mean precipitation, yet in many hydrological applications extreme precipitation is the main interest. In this study, we examine and compare the statistical properties of extreme precipitation in observational records and in output from the North American Regional Climate Change Assessment Program (NARCCAP) ensemble of regional climate models, focusing specifically on Canada. Climate models have significant biases in extreme precipitation statistics which tend to be relatively more important for shorter-duration rainfall. We propose to deal with this issue by exploiting the fact that extreme rainfall events obey certain temporal scaling laws that we assume will remain largely unaltered in future climates, even if the frequency of these events change. This hypothesis is used to develop IDF curves for different regions of Canada. The general conclusion is that there is evidence of more extreme precipitation in future climates and these changes tend to be relatively more important for shorter durations and for higher return periods. However, the multi-model approach also indicates that the exact amount of change is subject to considerable uncertainties.

  18. 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.

  19. 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

  20. 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

  1. [High-intensity focused ultrasound and prostate cancer: technology, state of the art and future].

    PubMed

    Vespasiani, G; Asimakopoulos, A D; Finazzi Agrò, E; Virgili, G

    2008-01-01

    BACKGROUND. The potential applications of the high-intensity focused ultrasound (HIFU) as a minimally invasive therapy of the localized prostate cancer explain the growing interest of the urologic community towards this technique. HIFU has been assessed for its role in the treatment of localized prostate cancer in patients who otherwise would not have benefited from surgery, and in local recurrences after radiation failure. Methods. Relevant information on HIFU treatment was identified through a literature search of published studies. RESULTS. High biochemical efficacy, excellent tumor local control and favorable mid- and long-term oncological data with a low morbidity rate have been shown in many series of patients. CONCLUSIONS. Although HIFU is a recent and emerging technology, it has been well studied and developed to a point that HIFU will undoubtedly be an effective alternative to radiation therapy.

  2. Light-Intensity Activity Attenuates Functional Decline in Older Cancer Survivors

    PubMed Central

    Blair, Cindy K.; Morey, Miriam C.; Desmond, Renee A.; Cohen, Harvey Jay; Sloane, Richard; Snyder, Denise C.; Demark-Wahnefried, Wendy

    2014-01-01

    While moderate-vigorous intensity physical activities (MVPA) confer the greatest health benefits, evidence suggests that light-intensity activities are also beneficial, particularly for older adults and individuals with moderate-severe comorbidities. Purpose To examine cross-sectional and longitudinal associations between light-intensity activity and physical function in older cancer survivors at increased risk for age- and treatment-related comorbidities, including accelerated functional decline. Methods The analysis included data from 641 breast, prostate, and colorectal cancer survivors (54% female) aged 65 and older who participated in a 1-year, home-based diet and exercise intervention designed to reduce the rate of physical function decline. ANCOVA was used to compare means of physical function across levels of PA intensity (low-light (LLPA): 1.5-2.0 METs; high-light (HLPA): 2.1-2.9 METs; MVPA: ≥3.0 METs). Results In cross-sectional analyses, increasing tertiles of light-intensity activity were associated with higher scores for all 3 measures of physical function (all p-values <0.005), after adjustment for age, sex, BMI, comorbidity, symptoms, and MVPA. Associations were stronger for HLPA than for LLPA. Compared with survivors who decreased or remained stable in MVPA and HLPA at the post-intervention follow-up, those who increased in HLPA, but decreased or remained stable in MVPA, reported higher physical function scores (LSMeans (95% CI): SF-36 physical function subscale: -5.58 (-7.96, -3.20) vs. -2.54 (-5.83, 0.75), p=0.14; basic lower extremity function: -2.00 (-3.45, -0.55) vs. 0.28 (-1.72, 2.28), p=0.07; advanced lower extremity function: -2.58 (-4.00, -1.15) vs. 0.44 (-1.52, 2.40), p=0.01). Conclusion Our findings suggest that increasing light-intensity activities, especially HLPA, may be a viable approach to reducing the rate of physical function decline in individuals who are unable or reluctant to initiate or maintain adequate levels of moderate-intensity

  3. Intensity-modulated radiotherapy for previously irradiated, recurrent head-and-neck cancer.

    PubMed

    Chen, Yi-Jen; Kuo, Jeffrey V; Ramsinghani, Nilam S; Al-Ghazi, Muthana S A L

    2002-01-01

    The purpose of this work is to evaluate our initial experience in treating previously irradiated, recurrent head-and-neck cancers using intensity-modulated radiotherapy (IMRT). Between July 1997 and September 1999, 12 patients with previously irradiated, locally recurrent head-and-neck cancers were treated with IMRT. These included cancers of the nasopharynx, oropharynx, hypopharynx, larynx, paranasal sinus, skin of the head-and-neck region, and malignant melanoma. Five of these 12 patients had received radiation as the primary treatment, with doses ranging from 66.0 to 126.0 Gy, and the remaining 7 patients had undergone definitive surgeries followed by an adjuvant course of radiation treatment, with doses ranging between 36.0 and 64.8 Gy. Recurrence after the initial course of radiation occurred in periods ranging from 4 to 35 months, with 11 of 12 cases recurring fully in the fields of previous irradiation. Recurrent tumors were treated with IMRT to total doses between 30 to 70 Gy (> 50 Gy in 10 cases) prescribed at the 75% to 92% isodose lines with daily fractions of 1.8 to 2 Gy. The results revealed that acute toxicities were acceptable except in 1 patient who died of aspiration pneumonia during the course of retreatment. There were 4 complete responders, 2 partial responders, and 2 patients with stable disease in the IMRT-treated volumes. Three patients received IMRT as adjuvant treatment following salvage surgery. At 4 to 16 months of follow-up, 7 patients were still alive, with 5 revealing no evidence of disease. In conclusion, this pilot study demonstrates that IMRT offers a viable mode of re-irradiation for recurrent head-and-neck cancers in previously irradiated sites. Longer follow-up time and a larger number of patients are needed to better define the therapeutic advantage of IMRT in recurrent, previously irradiated head-and-neck cancers.

  4. 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.

  5. 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.

  6. 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.

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

    PubMed Central

    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. PMID:25482761

  8. 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

  9. Magnetic resonance image-guided versus ultrasound-guided high-intensity focused ultrasound in the treatment of breast cancer

    PubMed Central

    Li, Sheng; Wu, Pei-Hong

    2013-01-01

    Image-guided high-intensity focused ultrasound (HIFU) has been used for more than ten years, primarily in the treatment of liver and prostate cancers. HIFU has the advantages of precise cancer ablation and excellent protection of healthy tissue. Breast cancer is a common cancer in women. HIFU therapy, in combination with other therapies, has the potential to improve both oncologic and cosmetic outcomes for breast cancer patients by providing a curative therapy that conserves mammary shape. Currently, HIFU therapy is not commonly used in breast cancer treatment, and efforts to promote the application of HIFU is expected. In this article, we compare different image-guided models for HIFU and reviewed the status, drawbacks, and potential of HIFU therapy for breast cancer. PMID:23237221

  10. 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.

  11. 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.

  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. Diffraction of high-intensity field in focal region as dynamics of nonlinear system with low-frequency dispersion

    NASA Astrophysics Data System (ADS)

    Rudenko, O. V.; Hedberg, C. M.

    2015-01-01

    The stationary profile in the focal region of a focused nonlinear acoustic wave is described. Three models following from the Khokhlov-Zabolotskaya (KZ) equation with three independent variables are used: (i) the simplified one-dimensional Ostrovsky-Vakhnenko equation, (ii) the system of equations for paraxial series expansion of the acoustic field in powers of transverse coordinates, and (iii) the KZ equation reduced to two independent variables. The structure of the last equation is analogous to the Westervelt equation. Linearization through the Legendre transformation and reduction to the well-studied Euler-Tricomi equation is shown. At high intensities the stationary profiles are periodic sequences of arc sections having singularities of derivative in their matching points. The occurrence of arc profiles was pointed out by Makov. These appear in different nonlinear systems with low-frequency dispersion. Profiles containing discontinuities (shock fronts) change their form while passing through the focal region and are non-stationary waves. The numerical estimations of maximum pressure and intensity in the focus agree with computer calculations and experimental measurements.

  15. 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

  16. Intensity modulated radiotherapy induces pro-inflammatory and pro-survival responses in prostate cancer patients

    PubMed Central

    EL-SAGHIRE, HOUSSEIN; VANDEVOORDE, CHARLOT; OST, PIET; MONSIEURS, PIETER; MICHAUX, ARLETTE; DE MEERLEER, GERT; BAATOUT, SARAH; THIERENS, HUBERT

    2014-01-01

    Intensity modulated radiotherapy (IMRT) is one of the modern conformal radiotherapies that is widely used within the context of cancer patient treatment. It uses multiple radiation beams targeted to the tumor, however, large volumes of the body receive low doses of irradiation. Using γ-H2AX and global genome expression analysis, we studied the biological responses induced by low doses of ionizing radiation in prostate cancer patients following IMRT. By means of different bioinformatics analyses, we report that IMRT induced an inflammatory response via the induction of viral, adaptive, and innate immune signaling. In response to growth factors and immune-stimulatory signaling, positive regulation in the progression of cell cycle and DNA replication were induced. This denotes pro-inflammatory and pro-survival responses. Furthermore, double strand DNA breaks were induced in every patient 30 min after the treatment and remaining DNA repair and damage signaling continued after 18–24 h. Nine genes belonging to inflammatory responses (TLR3, SH2D1A and IL18), cell cycle progression (ORC4, SMC2 and CCDC99) and DNA damage and repair (RAD17, SMC6 and MRE11A) were confirmed by quantitative RT-PCR. This study emphasizes that the risk assessment of health effects from the out-of-field low doses during IMRT should be of concern, as these may increase the risk of secondary cancers and/or systemic inflammation. PMID:24435511

  17. An 11-channel radio frequency phased array coil for magnetic resonance guided high-intensity focused ultrasound of the breast.

    PubMed

    Minalga, E; Payne, A; Merrill, R; Todd, N; Vijayakumar, S; Kholmovski, E; Parker, D L; Hadley, J R

    2013-01-01

    In this study, a radio frequency phased array coil was built to image the breast in conjunction with a magnetic resonance guided high-intensity focused ultrasound (MRgHIFU) device designed specifically to treat the breast in a treatment cylinder with reduced water volume. The MRgHIFU breast coil was comprised of a 10-channel phased array coil placed around an MRgHIFU treatment cylinder where nearest-neighbor decoupling was achieved with capacitive decoupling in a shared leg. In addition a single loop coil was placed at the chest wall making a total of 11 channels. The radio frequency coil array design presented in this work was chosen based on ease of implementation, increased visualization into the treatment cylinder, image reconstruction speed, temporal resolution, and resulting signal-to-noise ratio profiles. This work presents a dedicated 11-channel coil for imaging of the breast tissue in the MRgHIFU setup without obstruction of the ultrasound beam and, specifically, compares its performance in signal-to-noise, overall imaging time, and temperature measurement accuracy to that of the standard single chest-loop coil typically used in breast MRgHIFU.

  18. [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.

  19. Superdressed H+2 and H2+3 molecular ions in intense, high-frequency laser fields

    NASA Astrophysics Data System (ADS)

    Zuo, T.; Bandrauk, A. D.

    1995-01-01

    We study the radiative distortion of the lowest two potential surfaces of H+2 and H2+3 molecular ions in a superintense (I>~1016 W/cm2), high-frequency, linearly polarized laser field, using the space-translation or acceleration representation of laser-matter interaction. The electron clouds undergo field-induced redistribution in the molecular ions due to the presence of field-induced ``dichotomous'' dressed Coulomb potentials. Such super-field-dressed systems have a greater tendency to transfer electronic charge into the region between the nuclei and hence become more ``stable'' than the field-free ones. For example, at the equilibrium nuclear separation the dissociation energy of the superdressed H+2 is found to increase by about 20% compared with the field-free H+2. More dramatically, the lowest two surfaces of H2+3 that are repulsive in zero field become attractive (bonding) in the presence of an intense, high-frequency field. The possibility of molecules becoming stabilized against both ionization and dissociation in superintense fields is discussed.

  20. Efficacy of Pulsed 405-nm Light-Emitting Diodes for Antimicrobial Photodynamic Inactivation: Effects of Intensity, Frequency, and Duty Cycle

    PubMed Central

    Gillespie, Jonathan B.; Given, Martin J.; Wilson, Mark P.; Judd, Martin D.; Timoshkin, Igor V.; MacGregor, Scott J.

    2017-01-01

    Abstract Objective: This study investigates possible advantages in pulsed over continuous 405-nm light-emitting diode (LED) light for bacterial inactivation and energy efficiency. Background: Alternative nonantibiotic methods of disinfection and infection control have become of significant interest. Recent studies have demonstrated the application of systems using 405-nm LEDs for continuous disinfection of the clinical environment, and also for potential treatment of contaminated wounds. Methods: Liquid suspensions of 103 colony-forming units/mL populations of Staphylococcus aureus were subject to pulsed 405-nm light of different frequencies, duty cycles, and intensities and for different lengths of time. Results: Pulsed exposures with the same average irradiance of 16 mW/cm2 and varying duty cycle (25%, 50%, 75%) showed very similar performance compared with continuous exposures, with 95–98% reduction of S. aureus achieved for all duty cycles. The pulsing frequency was varied in intervals from 100 Hz to 10 kHz and appeared to have little effect on antimicrobial efficacy. However, when comparing pulsed with continuous exposure, an improvement in inactivation per unit optical energy was achieved, with results showing an increase of approximately 83% in optical efficiency. Conclusions: These results suggest that under pulsed conditions, a lower energy consumption and lower perceived brightness could be achieved, thus potentially providing improved operating conditions for medical/infection control applications without compromising antimicrobial efficacy. PMID:27759498

  1. Moderate-Intensity Physical Activity Ameliorates the Breast Cancer Risk in Diabetic Women

    PubMed Central

    Torres-Mejía, Gabriela; Angeles-Llerenas, Angélica; Ortega-Olvera, Carolina; Lazcano-Ponce, Eduardo; Ziv, Elad; Pulido-Rodríguez, José; García-Solis, Manuel de Jesús; Murillo-Zamora, Efrén; Vázquez-Lara, Julia; Romieu, Isabelle

    2012-01-01

    OBJECTIVE To evaluate the association between self-reported diabetes and the risk of breast cancer (BC) and its interaction with moderate-intensity physical activity in pre- and postmenopausal Mexican women. RESEARCH DESIGN AND METHODS A population-based case-control study was conducted using 1,000 incident case subjects and 1,074 control subjects. Blood samples and information on health, diet, physical activity, and anthropometric measurements were obtained. RESULTS The association between diabetes and BC risk decreased with increasing tertiles of moderate-intensity physical activity (odds ratio [OR] = 4.9 [95% CI 2.3–10.8]; 3.0 [1.3–6.9]; and 1.0 [0.1–9.2], respectively, for each tertile) (test for interaction = 0.04). Compared with the women in the lowest tertiles, increased risk was observed in those premenopausal women with the highest serum C-peptide, IGF-1, and IGF-1 binding protein 3 levels. CONCLUSIONS Moderate-intensity physical activity can substantially ameliorate the increased BC risk in diabetic women. PMID:23033240

  2. Evolution in Intensity and Frequency of Extreme Events of Precipitation in Northeast Region and Brazilian Amazon in XXI Century

    NASA Astrophysics Data System (ADS)

    Fonseca, P. M.; Veiga, J. A.; Correia, F. S.; Brito, A. L.

    2013-05-01

    The aim of this research was evaluate changes in frequency and intensity of extreme events of precipitation in Brazilian Amazon and Northeast Region, doubling CO2 concentration in agreement of IPCC A2 emissions scenarios (Nakicenovic et al., 2001). For this evaluation was used ETA model (Chou et al., 2011), forced with CCSM3 Global model data (Meehl, 2006) to run 4 experiments, only for January, February and March: 1980-1990, 2000-2010, 2040-2050 and 2090-2100. Using the first decade as reference (1980-1990), was evaluated changes occurred in following decades, with a methodology to classify extremes events adapted from Frich (2002) and Gao (2006). Higher was the class, more intense is the event. An increase of 25% was observed in total precipitation in Brazilian Amazon for the end of XXI century and 12% for extreme events type 1, 9% for events type 2 and 10% for type 3. By the other hand, a 17% decrease of precipitation in Brazilian Northeast was observed, and a pronounced decay of 24% and 15% in extreme events contribution type 1 and 2 to total amount of precipitation, respectively. The difference between total normal type events was positive in this three decades compared with reference decade 1980-1990, varying positively from 4 to 6 thousand events included in normality by decade, these events was decreased in your majority of Class 1 events, which presented a decay of at least 3.500 events by each decade. This suggests an intensification of extreme events, considering that the amount of precipitation by class increased, and the number of events by class decreased. To Northeast region, an increasing in 9% of contribution to events type 3 class was observed, as well as in the frequency of this type of events (about of 700 more events). Major decreasing in number of classes extreme events occur in 2000-2010, to classes 1 and 3, with 7,2 and 5,6%, and by the end of century in class 3, with 4,5%. For the three analyzed decades a total decrease of 8.400 events was

  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. 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

  5. Proton Versus Intensity-Modulated Radiotherapy for Prostate Cancer: Patterns of Care and Early Toxicity

    PubMed Central

    2013-01-01

    Background Proton radiotherapy (PRT) is an emerging treatment for prostate cancer despite limited knowledge of clinical benefit or potential harms compared with other types of radiotherapy. We therefore compared patterns of PRT use, cost, and early toxicity among Medicare beneficiaries with prostate cancer with those of intensity-modulated radiotherapy (IMRT). Methods We performed a retrospective study of all Medicare beneficiaries aged greater than or equal to 66 years who received PRT or IMRT for prostate cancer during 2008 and/or 2009. We used multivariable logistic regression to identify factors associated with receipt of PRT. To assess toxicity, each PRT patient was matched with two IMRT patients with similar clinical and sociodemographic characteristics. The main outcome measures were receipt of PRT or IMRT, Medicare reimbursement for each treatment, and early genitourinary, gastrointestinal, and other toxicity. All statistical tests were two-sided. Results We identified 27,647 men; 553 (2%) received PRT and 27,094 (98%) received IMRT. Patients receiving PRT were younger, healthier, and from more affluent areas than patients receiving IMRT. Median Medicare reimbursement was $32,428 for PRT and $18,575 for IMRT. Although PRT was associated with a statistically significant reduction in genitourinary toxicity at 6 months compared with IMRT (5.9% vs 9.5%; odds ratio [OR] = 0.60, 95% confidence interval [CI] = 0.38 to 0.96, P = .03), at 12 months post-treatment there was no difference in genitourinary toxicity (18.8% vs 17.5%; OR = 1.08, 95% CI = 0.76 to 1.54, P = .66). There was no statistically significant difference in gastrointestinal or other toxicity at 6 months or 12 months post-treatment. Conclusions Although PRT is substantially more costly than IMRT, there was no difference in toxicity in a comprehensive cohort of Medicare beneficiaries with prostate cancer at 12 months post-treatment. PMID:23243199

  6. 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.

  7. Patterns of Disease Recurrence Following Treatment of Oropharyngeal Cancer With Intensity Modulated Radiation Therapy

    SciTech Connect

    Garden, Adam S.; Dong, Lei; Morrison, William H.; Stugis, Erich M.; Glisson, Bonnie S.; Schwartz, David L.; Kies, Merill S.; Ang, K. Kian; Rosenthal, David I.

    2013-03-15

    Purpose: To report mature results of a large cohort of patients diagnosed with squamous cell carcinoma of the oropharynx who were treated with intensity modulated radiation therapy (IMRT). Methods and Materials: The database of patients irradiated at The University of Texas, M.D. Anderson Cancer Center was searched for patients diagnosed with oropharyngeal cancer and treated with IMRT between 2000 and 2007. A retrospective review of outcome data was performed. Results: The cohort consisted of 776 patients. One hundred fifty-nine patients (21%) were current smokers, 279 (36%) former smokers, and 337 (43%) never smokers. T and N categories and American Joint Committee on Cancer group stages were distributed as follows: T1/x, 288 (37%); T2, 288 (37%); T3, 113 (15%); T4, 87 (11%); N0, 88(12%); N1/x, 140 (18%); N2a, 101 (13%); N2b, 269 (35%); N2c, 122 (16%); and N3, 56 (7%); stage I, 18(2%); stage II, 40(5%); stage III, 150(19%); and stage IV, 568(74%). Seventy-one patients (10%) presented with nodes in level IV. Median follow-up was 54 months. The 5-year overall survival, locoregional control, and overall recurrence-free survival rates were 84%, 90%, and 82%, respectively. Primary site recurrence developed in 7% of patients, and neck recurrence with primary site control in 3%. We could only identify 12 patients (2%) who had locoregional recurrence outside the high-dose target volumes. Poorer survival rates were observed in current smokers, patients with larger primary (T) tumors and lower neck disease. Conclusions: Patients with oropharyngeal cancer treated with IMRT have excellent disease control. Locoregional recurrence was uncommon, and most often occurred in the high dose volumes. Parotid sparing was accomplished in nearly all patients without compromising tumor coverage.

  8. Salvage image-guided intensity modulated or stereotactic body reirradiation of local recurrence of prostate cancer

    PubMed Central

    Jereczek-Fossa, B A; Fodor, C; Bazzani, F; Maucieri, A; Ronchi, S; Ferrario, S; Colangione, S P; Gerardi, M A; Caputo, M; Cecconi, A; Gherardi, F; Vavassori, A; Comi, S; Cambria, R; Garibaldi, C; Cattani, F; De Cobelli, O; Orecchia, R

    2015-01-01

    Objective: To retrospectively evaluate external beam reirradiation (re-EBRT) delivered to the prostate/prostatic bed for local recurrence, after radical or adjuvant/salvage radiotherapy (RT). Methods: 32 patients received re-EBRT between February 2008 and October 2013. All patients had clinical/radiological local relapse in the prostate or prostatic bed and no distant metastasis. re-EBRT was delivered with selective RT technologies [stereotactic RT including CyberKnifeTM (Accuray, Sunnyvale, CA); image-guidance and intensity-modulated RT etc.]. Toxicity was evaluated using the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer criteria. Biochemical control was assessed according to the Phoenix definition (NADIR + 2 ng ml−1). Results: Acute urinary toxicity: G0, 24 patients; G1, 6 patients; G2, 2 patients. Acute rectal toxicity: G0, 28 patients; G1, 2 patients; and G2, 1 patient. Late urinary toxicity (evaluated in 30 cases): G0, 23 patients; G1, 6 patients; G2, 1 patient. Late renal toxicity: G0, 25 patients; G1, 5 patients. A mean follow-up of 21.3 months after re-EBRT showed that 13 patients were free of cancer, 3 were alive with biochemical relapse and 12 patients were alive with clinically evident disease. Four patients had died: two of disease progression and two of other causes. Conclusion: re-EBRT using modern technology is a feasible approach for local prostate cancer recurrence offering 2-year tumour control in about half of the patients. Toxicity of re-EBRT is low. Future studies are needed to identify the patients who would benefit most from this treatment. Advances in knowledge: Our series, based on experience in one hospital alone, shows that re-EBRT for local relapse of prostate cancer is feasible and offers a 2-year cure in about half of the patients. PMID:26055506

  9. 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.

  10. 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.

  11. 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.

  12. Phase-noise characteristics of a 25-GHz-spaced optical frequency comb based on a phase- and intensity-modulated laser.

    PubMed

    Ishizawa, Atsushi; Nishikawa, Tadashi; Mizutori, Akira; Takara, Hidehiko; Takada, Atsushi; Sogawa, Tetsuomi; Koga, Masafumi

    2013-12-02

    We investigated phase-noise characteristics of both a phase/intensity-modulated laser with 25-GHz mode spacing and a mode-locked fiber laser with carrier-envelope-offset (CEO) locking. As the separation from the frequency of the continuous wave (CW) laser diode (LD) for a seed light source increases, the integrated phase noise of each comb mode of both the phase/intensity-modulated laser and supercontinuum light originating from it increases with the same slope as a function of mode number. The dependence of the integrated phase noise on mode number with the phase/intensity-modulated laser is much larger than with the mode-locked fiber laser of the CEO locking. However, the phase noise of the phase/intensity-modulated laser is extremely lower than that of the mode-locked fiber laser with CEO locking in the frequency region around the CW LD. The phase noise of the phase/intensity-modulated laser with 25-GHz mode spacing and that of the mode-locked fiber laser with the CEO locking could be estimated and were found to be almost the same at the wavelengths required in an f-to-2f self-referencing interferometer. Our experimental results indicate the possibility of achieving an offset-frequency-locked frequency comb with the phase/intensity-modulated laser.

  13. 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.

  14. A High Frequency of BRCA Mutations in Young Black Women with Breast Cancer from Florida

    PubMed Central

    Pal, Tuya; Bonner, Devon; Cragun, Deborah; Monteiro, Alvaro N.A.; Phelan, Catherine; Servais, Lily; Kim, Jongphil; Narod, Steven A.; Akbari, Mohammad R.; Vadaparampil, Susan

    2015-01-01

    PURPOSE Black women are disproportionately affected with triple negative breast cancer and have relatively poor survival. It is not known to what extent differences in clinical presentation of breast cancer in Non-Hispanic White (NHW) women and Black women can be accounted for by the presence of mutations in the BRCA1 and BRCA2 (BRCA) genes. We sought to evaluate the frequency of BRCA pathogenic variants in a population-based sample of young Black women with breast cancer. PATIENTS AND METHODS Black women diagnosed with invasive breast cancer at or before age 50 from 2009 to 2012 were recruited to the study through the Florida Cancer Registry. Participants underwent genetic counseling, completed a study questionnaire and consented to release of their medical records. Saliva specimens were collected for BRCA sequencing and large rearrangement testing through MLPA. RESULTS A DNA sample was evaluated for 396 women of whom 49 (12.4%) had a mutation in BRCA1 or BRCA2. Eight recurrent mutations accounted for 49% of all pathogenic variants. CONCLUSIONS The prevalence of BRCA mutations among our Florida-based sample of young Black women with breast cancer exceeds that previously reported for NHW women. It is appropriate to recommend BRCA testing in all young Black women with invasive breast cancer. PMID:26287763

  15. Implementation of intensity modulated radiotherapy for prostate cancer in a private radiotherapy service in Mexico

    PubMed Central

    Poitevin-Chacón, María Adela; Reséndiz González, Gabriel; Alvarado Zermeño, Adriana; Flores Castro, Jesús Manuel; Flores Balcázar, Christian Haydée; Rosales Pérez, Samuel; Pérez Pastenes, Miguel Angel; Rodríguez Laguna, Alejandro; Vázquez Fernández, Patricio; Calvo Fernández, Alejandro; Bastida Ventura, Jorge

    2014-01-01

    Intensity modulated radiation therapy (IMRT) allows physicians to deliver higher conformal doses to the tumour, while avoiding adjacent structures. As a result the probability of tumour control is higher and toxicity may be reduced. However, implementation of IMRT is highly complex and requires a rigorous quality assurance (QA) program both before and during treatment. The present article describes the process of implementing IMRT for localized prostate cancer in a radiation therapy department. In our experience, IMRT implementation requires careful planning due to the need to simultaneously implement specialized software, multifaceted QA programs, and training of the multidisciplinary team. Establishing standardized protocols and ensuring close collaboration between a multidisciplinary team is challenging but essential. PMID:25535587

  16. 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.

  17. Accelerated Partial Breast Irradiation with Intensity-Modulated Radiotherapy Is Feasible for Chinese Breast Cancer Patients

    PubMed Central

    He, Zhenyu; Wu, Sangang; Zhou, Juan; Sun, Jiayan; Lin, Qin; Lin, Huanxin; Guan, Xunxing

    2014-01-01

    Purpose Several accelerated partial breast irradiation (APBI) techniques are being investigated in patients with early-stage breast cancer. The present study evaluated the feasibility, early toxicity, initial efficacy, and cosmetic outcomes of accelerated partial breast intensity-modulated radiotherapy (IMRT) for Chinese female patients with early-stage breast cancer after breast-conserving surgery. Methods A total of 38 patients met the inclusion criteria and an accelerated partial breast intensity-modulated radiotherapy (APBI-IMRT) plan was designed for each patient. The prescription dose was 34 Gy in 10 fractions, 3.4 Gy per fraction, twice a day, in intervals of more than 6 hours. Results Of the 38 patients, six patients did not meet the planning criteria. The remaining 32 patients received APBI-IMRT with a mean target volume conformity index of 0.67 and a dose homogeneity index of 1.06. The median follow-up time was 53 months and no local recurrence or distant metastasis was detected. The most common acute toxicities observed within 3 months after radiotherapy were erythema, breast edema, pigmentation, and pain in the irradiated location, among which 43.8%, 12.5%, 31.3%, and 28.1% were grade 1 toxicities, respectively. The most common late toxicities occurring after 3 months until the end of the follow-up period were breast edema, pigmentation, pain in the irradiated location, and subcutaneous fibrosis, among which 6.2%, 28.1%, 21.9%, and 37.5% were grade 1 toxicities, respectively. Thirty-one patients (96.8%) had fine or excellent cosmetic outcomes, and only one patient had a poor cosmetic outcome. Conclusion It is feasible for Chinese females to receive APBI-IMRT after breast conserving surgery. The radiotherapeutic toxicity is acceptable, and both the initial efficacy and cosmetic outcomes are good. PMID:25320624

  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. Robust and fast characterization of OCT-based optical attenuation using a novel frequency-domain algorithm for brain cancer detection

    NASA Astrophysics Data System (ADS)

    Yuan, Wu; Kut, Carmen; Liang, Wenxuan; Li, Xingde

    2017-03-01

    Cancer is known to alter the local optical properties of tissues. The detection of OCT-based optical attenuation provides a quantitative method to efficiently differentiate cancer from non-cancer tissues. In particular, the intraoperative use of quantitative OCT is able to provide a direct visual guidance in real time for accurate identification of cancer tissues, especially these without any obvious structural layers, such as brain cancer. However, current methods are suboptimal in providing high-speed and accurate OCT attenuation mapping for intraoperative brain cancer detection. In this paper, we report a novel frequency-domain (FD) algorithm to enable robust and fast characterization of optical attenuation as derived from OCT intensity images. The performance of this FD algorithm was compared with traditional fitting methods by analyzing datasets containing images from freshly resected human brain cancer and from a silica phantom acquired by a 1310 nm swept-source OCT (SS-OCT) system. With graphics processing unit (GPU)-based CUDA C/C++ implementation, this new attenuation mapping algorithm can offer robust and accurate quantitative interpretation of OCT images in real time during brain surgery.

  20. Robust and fast characterization of OCT-based optical attenuation using a novel frequency-domain algorithm for brain cancer detection

    PubMed Central

    Yuan, Wu; Kut, Carmen; Liang, Wenxuan; Li, Xingde

    2017-01-01

    Cancer is known to alter the local optical properties of tissues. The detection of OCT-based optical attenuation provides a quantitative method to efficiently differentiate cancer from non-cancer tissues. In particular, the intraoperative use of quantitative OCT is able to provide a direct visual guidance in real time for accurate identification of cancer tissues, especially these without any obvious structural layers, such as brain cancer. However, current methods are suboptimal in providing high-speed and accurate OCT attenuation mapping for intraoperative brain cancer detection. In this paper, we report a novel frequency-domain (FD) algorithm to enable robust and fast characterization of optical attenuation as derived from OCT intensity images. The performance of this FD algorithm was compared with traditional fitting methods by analyzing datasets containing images from freshly resected human brain cancer and from a silica phantom acquired by a 1310 nm swept-source OCT (SS-OCT) system. With graphics processing unit (GPU)-based CUDA C/C++ implementation, this new attenuation mapping algorithm can offer robust and accurate quantitative interpretation of OCT images in real time during brain surgery. PMID:28327613

  1. Robust and fast characterization of OCT-based optical attenuation using a novel frequency-domain algorithm for brain cancer detection.

    PubMed

    Yuan, Wu; Kut, Carmen; Liang, Wenxuan; Li, Xingde

    2017-03-22

    Cancer is known to alter the local optical properties of tissues. The detection of OCT-based optical attenuation provides a quantitative method to efficiently differentiate cancer from non-cancer tissues. In particular, the intraoperative use of quantitative OCT is able to provide a direct visual guidance in real time for accurate identification of cancer tissues, especially these without any obvious structural layers, such as brain cancer. However, current methods are suboptimal in providing high-speed and accurate OCT attenuation mapping for intraoperative brain cancer detection. In this paper, we report a novel frequency-domain (FD) algorithm to enable robust and fast characterization of optical attenuation as derived from OCT intensity images. The performance of this FD algorithm was compared with traditional fitting methods by analyzing datasets containing images from freshly resected human brain cancer and from a silica phantom acquired by a 1310 nm swept-source OCT (SS-OCT) system. With graphics processing unit (GPU)-based CUDA C/C++ implementation, this new attenuation mapping algorithm can offer robust and accurate quantitative interpretation of OCT images in real time during brain surgery.

  2. Use of radar QPE for the derivation of Intensity-Duration-Frequency curves in a range of climatic regimes

    NASA Astrophysics Data System (ADS)

    Marra, Francesco; Morin, Efrat

    2015-12-01

    Intensity-Duration-Frequency (IDF) curves are widely used in flood risk management because they provide an easy link between the characteristics of a rainfall event and the probability of its occurrence. Weather radars provide distributed rainfall estimates with high spatial and temporal resolutions and overcome the scarce representativeness of point-based rainfall for regions characterized by large gradients in rainfall climatology. This work explores the use of radar quantitative precipitation estimation (QPE) for the identification of IDF curves over a region with steep climatic transitions (Israel) using a unique radar data record (23 yr) and combined physical and empirical adjustment of the radar data. IDF relationships were derived by fitting a generalized extreme value distribution to the annual maximum series for durations of 20 min, 1 h and 4 h. Arid, semi-arid and Mediterranean climates were explored using 14 study cases. IDF curves derived from the study rain gauges were compared to those derived from radar and from nearby rain gauges characterized by similar climatology, taking into account the uncertainty linked with the fitting technique. Radar annual maxima and IDF curves were generally overestimated but in 70% of the cases (60% for a 100 yr return period), they lay within the rain gauge IDF confidence intervals. Overestimation tended to increase with return period, and this effect was enhanced in arid climates. This was mainly associated with radar estimation uncertainty, even if other effects, such as rain gauge temporal resolution, cannot be neglected. Climatological classification remained meaningful for the analysis of rainfall extremes and radar was able to discern climatology from rainfall frequency analysis.

  3. 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.

  4. Role of Intensity-Modulated Radiotherapy in Reducing Toxicity in Dose Escalation for Localized Prostate Cancer

    SciTech Connect

    Al-Mamgani, Abrahim Heemsbergen, Wilma D.; Peeters, Stephanie T.H.; Lebesque, Joos V.

    2009-03-01

    Purpose: To compare the acute and late gastrointestinal (GI) and genitourinary (GU) toxicity in prostate cancer patients treated to a total dose of 78 Gy with either a three-conformal radiotherapy technique with a sequential boost (SEQ) or a simultaneous integrated boost using intensity-modulated radiotherapy (SIB-IMRT). Patients and Methods: A total of 78 prostate cancer patients participating in the randomized Dutch trial comparing 68 Gy and 78 Gy were the subject of this analysis. They were all treated at the same institution to a total dose of 78 Gy. The median follow-up was 76 and 56 months for the SEQ and SIB-IMRT groups, respectively. The primary endpoints were acute and late GI and GU toxicity. Results: A significantly lower incidence of acute Grade 2 or greater GI toxicity occurred in patients treated with SIB-IMRT compared with SEQ (20% vs. 61%, p = 0.001). For acute GU toxicity and late GI and GU toxicity, the incidence was lower after SIB-IMRT, but these differences were not statistically significant. No statistically significant difference were found in the 5-year freedom from biochemical failure rate (Phoenix definition) between the two groups (70% for the SIB-IMRT group vs. 61% for the SEQ group, p = 0.3). The same was true for the 5-year freedom from clinical failure rate (90% vs. 72%, p = 0.07). Conclusion: The results of our study have shown that SIB-IMRT reduced the toxicity without compromising the outcome in patients with localized prostate cancer treated to 78 Gy radiation.

  5. Intensity-Modulated Radiotherapy for Head and Neck Cancer of Unknown Primary: Toxicity and Preliminary Efficacy

    SciTech Connect

    Klem, Michelle L. Mechalakos, James G.; Wolden, Suzanne L.; Zelefsky, Michael J.; Singh, Bhuvanesh; Kraus, Dennis; Shaha, Ashok; Shah, Jatin; Pfister, David G.; Lee, Nancy Y.

    2008-03-15

    Purpose: Unknown primary head and neck cancers often require comprehensive mucosal and bilateral neck irradiation. With conventional techniques, significant toxicity can develop. Intensity-modulated radiotherapy (IMRT) has the potential to minimize the toxicity. Methods and Materials: Between 2000 and 2005, 21 patients underwent IMRT for unknown primary head and neck cancer at our center. Of the 21 patients, 5 received IMRT with definitive intent and 16 as postoperative therapy; 14 received concurrent chemotherapy and 7 IMRT alone. The target volumes included the bilateral neck and mucosal surface. The median dose was 66 Gy. Acute and chronic toxicities, esophageal strictures, and percutaneous endoscopic gastrostomy tube dependence were evaluated. Progression-free survival, regional progression-free survival, distant metastasis-free survival, and overall survival were estimated with Kaplan-Meier curves. Results: With a median follow-up of 24 months, the 2-year regional progression-free survival, distant metastasis-free survival, and overall survival rate was 90%, 90%, and 85%, respectively. Acute grade 1 and 2 xerostomia was seen in 57% and 43% of patients, respectively. Salivary function improved with time. Percutaneous endoscopic gastrostomy tube placement was required in 72% with combined modality treatment and 43% with IMRT alone. Only 1 patient required percutaneous endoscopic gastrostomy support at the last follow-up visit. Two patients treated with combined modality and one treated with IMRT alone developed esophageal strictures, but all had improvement or resolution with dilation. Conclusion: The preliminary analysis of IMRT for unknown primary head and neck cancer has shown acceptable toxicity and encouraging efficacy. The analysis of the dosimetric variables showed excellent tumor coverage and acceptable doses to critical normal structures. Esophageal strictures developed but were effectively treated with dilation. Techniques to limit the esophageal dose

  6. Clinical response of advanced cancer patients to cellular immunotherapy and intensity-modulated radiation therapy

    PubMed Central

    Hasumi, Kenichiro; Aoki, Yukimasa; Wantanabe, Ryuko; Mann, Dean L

    2013-01-01

    Patients afflicted with advanced cancers were treated with the intratumoral injection of autologous immature dendritic cells (iDCs) followed by activated T-cell infusion and intensity-modulated radiation therapy (IMRT). A second round of iDCs and activated T cells was then administered to patients after the last radiation cycle. This complete regimen was repeated for new and recurring lesions after 6 weeks of follow-up. One year post therapy, outcome analyses were performed to evaluate treatment efficacy. Patients were grouped according to both the number and size of tumors and clinical parameters at treatment initiation, including recurrent disease after standard cancer therapy, Stage IV disease, and no prior therapy. Irrespective of prior treatment status, 23/37 patients with ≤ 5 neoplastic lesions that were ≤ 3 cm in diameter achieved complete responses (CRs), and 5/37 exhibited partial responses (PRs). Among 130 individuals harboring larger and more numerous lesions, CRs were observed in 7/74 patients that had received prior SCT and in 2/56 previously untreated patients. Some patients manifested immune responses including an increase in CD8+CD56+ lymphocytes among circulating mononuclear cells in the course of treatment. To prospectively explore the therapeutic use of these cells, CD8+ cells were isolated from patients that had been treated with cellular immunotherapy and IMRT, expanded in vitro, and injected into recurrent metastatic sites in 13 individuals who underwent the same immunoradiotherapeutic regimens but failed to respond. CRs were achieved in 34 of 58 of such recurrent lesions while PRs in 17 of 58. These data support the expanded use of immunoradiotherapy in advanced cancer patients exhibiting progressive disease. PMID:24349874

  7. High-Intensity Focused Ultrasound (HIFU) in Localized Prostate Cancer Treatment

    PubMed Central

    Alkhorayef, Mohammed; Mahmoud, Mustafa Z.; Alzimami, Khalid S.; Sulieman, Abdelmoneim; Fagiri, Maram A.

    2015-01-01

    Summary Background High-intensity focused ultrasound (HIFU) applies high-intensity focused ultrasound energy to locally heat and destroy diseased or damaged tissue through ablation. This study intended to review HIFU to explain the fundamentals of HIFU, evaluate the evidence concerning the role of HIFU in the treatment of prostate cancer (PC), review the technologies used to perform HIFU and the published clinical literature regarding the procedure as a primary treatment for PC. Material/Methods Studies addressing HIFU in localized PC were identified in a search of internet scientific databases. The analysis of outcomes was limited to journal articles written in English and published between 2000 and 2013. Results HIFU is a non-invasive approach that uses a precisely delivered ultrasound energy to achieve tumor cell necrosis without radiation or surgical excision. In current urological oncology, HIFU is used clinically in the treatment of PC. Clinical research on HIFU therapy for localized PC began in the 1990s, and the majority of PC patients were treated with the Ablatherm device. Conclusions HIFU treatment for localized PC can be considered as an alternative minimally invasive therapeutic modality for patients who are not candidates for radical prostatectomy. Patients with lower pre-HIFU PSA level and favourable pathologic Gleason score seem to present better oncologic outcomes. Future advances in technology and safety will undoubtedly expand the HIFU role in this indication as more of patient series are published, with a longer follow-up period. PMID:25806099

  8. Intensive or not surveillance of patients with colorectal cancer after curative resection

    PubMed Central

    Rosati, Gerardo

    2010-01-01

    It is common practice to follow patients with colorectal cancer for some years after resection and/or adjuvant treatment. Data are lacking about how often patients should be seen, what tests should be performed, and what surveillance strategy has a significant impact on patient outcome. Seven randomized trials have addressed this issue, but none had sufficient statistical power. Four published meta-analyses have established that overall survival is significantly improved for patients in the more intensive programs of follow-up. This improvement amounts to a risk difference of 7% (95% CI: 3%-12%, P = 0.002) in 5-year survival. This should be partly attributable to more frequent reoperation for cure of asymptomatic recurrence, or more intense follow-up, as well other factors, such increased psychosocial support and well-being, diet and lifestyle optimization, and/or improved treatment of coincidental diseases. A large-scale multicenter European study [Gruppo Italiano di Lavoro per la Diagnosi Anticipata (GILDA)] is underway to answer the question of what constitutes optimal surveillance for patients after primary therapy, based on an adequately powered study. PMID:20333780

  9. 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

  10. 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

  11. 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.

  12. 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.

  13. Hypofractionated Concomitant Intensity-Modulated Radiotherapy Boost for High-Risk Prostate Cancer: Late Toxicity

    SciTech Connect

    Quon, Harvey; Cheung, Patrick C.F.; Loblaw, D. Andrew; Morton, Gerard; Pang, Geordi; Szumacher, Ewa; Danjoux, Cyril; Choo, Richard; Thomas, Gillian; Kiss, Alex; Mamedov, Alexandre; Deabreu, Andrea

    2012-02-01

    Purpose: To report the acute and late toxicities of patients with high-risk localized prostate cancer treated using a concomitant hypofractionated, intensity-modulated radiotherapy boost combined with long-term androgen deprivation therapy. Methods and Materials: A prospective Phase I-II study of patients with any of the following: clinical Stage T3 disease, prostate-specific antigen level {>=}20 ng/mL, or Gleason score 8-10. A dose of 45 Gy (1.8 Gy/fraction) was delivered to the pelvic lymph nodes with a concomitant 22.5 Gy prostate intensity-modulated radiotherapy boost, to a total of 67.5 Gy (2.7 Gy/fraction) in 25 fractions within 5 weeks. Image guidance was performed using three gold seed fiducials. The National Cancer Institute Common Terminology Criteria for Adverse Events, version 3.0, and Radiation Therapy Oncology Group late morbidity scores were used to assess the acute and late toxicities, respectively. Biochemical failure was determined using the Phoenix definition. Results: A total of 97 patients were treated and followed up for a median of 39 months, with 88% having a minimum of 24 months of follow-up. The maximal toxicity scores were recorded. The grade of acute gastrointestinal toxicity was Grade 0 in 4%, 1 in 59%, and 2 in 37%. The grade of acute urinary toxicity was Grade 0 in 8%, 1 in 50%, 2 in 39%, and 3 in 4%. The grade of late gastrointestinal toxicity was Grade 0 in 54%, 1 in 40%, and 2 in 7%. No Grade 3 or greater late gastrointestinal toxicities developed. The grade of late urinary toxicity was Grade 0 in 82%, 1 in 9%, 2 in 5%, 3 in 3%, and 4 in 1% (1 patient). All severe toxicities (Grade 3 or greater) had resolved at the last follow-up visit. The 4-year biochemical disease-free survival rate was 90.5%. Conclusions: A hypofractionated intensity-modulated radiotherapy boost delivering 67.5 Gy in 25 fractions within 5 weeks combined with pelvic nodal radiotherapy and long-term androgen deprivation therapy was well tolerated, with low rates

  14. 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

  15. [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.

  16. 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.

  17. 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.

  18. Difference frequency generation of femtosecond mid infrared pulses employing intense Stokes pulses excitation in a photonic crystal fiber.

    PubMed

    Yao, Yuhong; Knox, Wayne H

    2012-11-05

    We demonstrate a novel method of generating milli-watt level mid-IR (MIR) pulses based on difference frequency mixing of the output from a 40 MHz Yb fiber Chirped Pulse Amplifier (CPA) and the intense Stokes pulses generated in a photonic crystal fiber (PCF) with two closely spaced zero dispersion wavelengths (ZDW). By taking advantage of the unique dispersion profile of the fiber, high power narrowband Stokes pulses are selectively generated in the normal dispersion region of the PCF with up to 1.45 nJ of pulse energy. Mixing with 12 nJ of pump pulses at 1035 nm in a type-II AgGaS(2) crystal yields MIR pulses around 5.5 µm wavelength with up to 3 mW of average power and 75 pJ of pulse energy. The reported method can be extended to generation of other MIR wavelengths by selecting PCFs with different second ZDWs or engineering the fiber dispersion profile via longitudinal tapering.

  19. [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.

  20. Analysis of KIR gene frequencies and HLA class I genotypes in prostate cancer and control group.

    PubMed

    Portela, P; Jobim, L F; Salim, P H; Koff, W J; Wilson, T J; Jobim, M R; Schwartsmann, G; Roesler, R; Jobim, M

    2012-10-01

    Prostate cancer is the second most common cancer in men, with a significant increase in incidence and mortality in men over 50 years of age. Natural killer cells (NK) are part of the innate immune system recognizing class I HLA molecules on target cells through their membrane receptors, called killer cell immunoglobulin-like receptors (KIR). The aim of our study is to evaluate the association between the KIR genes and HLA alleles in patients with prostate cancer and healthy controls. Two hundred patients with prostate cancer and 185 healthy controls were typed for HLA class I and KIR genes by PCR-SSP. When both groups were compared, no significant differences were found for HLA-C group 1 and group 2, HLA-Bw4, HLA-A3 and A11. No difference was seen either in KIR frequency between patients with prostate cancer and controls. In conclusion, our data suggest no potential role for the KIR gene system in prostate cancer.

  1. 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

  2. Intense Uptake in Amyloidosis of the Seminal Vesicles on 68Ga-PSMA PET Mimicking Locally Advanced Prostate Cancer.

    PubMed

    Stephens, Maximilian; Kim, David Insoo; Shepherd, Benjamin; Gustafson, Sonja; Thomas, Paul

    2017-02-01

    We report a case of benign senile seminal vesicle amyloidosis demonstrating intense Ga-prostate-specific membrane antigen (PSMA) uptake on PET/CT. A 68-year-old man underwent staging PSMA PET/CT and MRI for biopsy-proven prostate adenocarcinoma. There was an intense focus of Ga-PSMA uptake in the primary malignancy, as well as symmetrical intense uptake in the seminal vesicles bilaterally that was reported as multifocal disease with local invasion. Final histology after radical prostatectomy showed amyloidosis of the seminal vesicles without any evidence of prostate cancer. Care should be taken in the interpretation of seminal vesicle PSMA uptake to avoid overstaging.

  3. 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

  4. Exome sequencing identifies a spectrum of mutation frequencies in advanced and lethal prostate cancers

    PubMed Central

    Kumar, Akash; White, Thomas A.; MacKenzie, Alexandra P.; Clegg, Nigel; Lee, Choli; Dumpit, Ruth F.; Coleman, Ilsa; Ng, Sarah B.; Salipante, Stephen J.; Rieder, Mark J.; Nickerson, Deborah A.; Corey, Eva; Lange, Paul H.; Morrissey, Colm; Vessella, Robert L.; Nelson, Peter S.; Shendure, Jay

    2011-01-01

    To catalog protein-altering mutations that may drive the development of prostate cancers and their progression to metastatic disease systematically, we performed whole-exome sequencing of 23 prostate cancers derived from 16 different lethal metastatic tumors and three high-grade primary carcinomas. All tumors were propagated in mice as xenografts, designated the LuCaP series, to model phenotypic variation, such as responses to cancer-directed therapeutics. Although corresponding normal tissue was not available for most tumors, we were able to take advantage of increasingly deep catalogs of human genetic variation to remove most germline variants. On average, each tumor genome contained ∼200 novel nonsynonymous variants, of which the vast majority was specific to individual carcinomas. A subset of genes was recurrently altered across tumors derived from different individuals, including TP53, DLK2, GPC6, and SDF4. Unexpectedly, three prostate cancer genomes exhibited substantially higher mutation frequencies, with 2,000–4,000 novel coding variants per exome. A comparison of castration-resistant and castration-sensitive pairs of tumor lines derived from the same prostate cancer highlights mutations in the Wnt pathway as potentially contributing to the development of castration resistance. Collectively, our results indicate that point mutations arising in coding regions of advanced prostate cancers are common but, with notable exceptions, very few genes are mutated in a substantial fraction of tumors. We also report a previously undescribed subtype of prostate cancers exhibiting “hypermutated” genomes, with potential implications for resistance to cancer therapeutics. Our results also suggest that increasingly deep catalogs of human germline variation may challenge the necessity of sequencing matched tumor-normal pairs. PMID:21949389

  5. Epidemiological appraisal of studies of residential exposure to power frequency magnetic fields and adult cancers.

    PubMed Central

    Li, C Y; Thériault, G; Lin, R S

    1996-01-01

    OBJECTIVES: To appraise epidemiological evidence of the purported association between residential exposure to power frequency magnetic fields and adult cancers. METHODS: Literature review and epidemiological evaluation. RESULTS: Seven epidemiological studies have been conducted on the risk of cancer among adults in relation to residential exposure to power frequency magnetic fields. Leukaemia was positively associated with magnetic fields in three case-control studies. The other two case-control studies and two cohort studies did not show such a link. Brain tumours and breast cancer have rarely been examined by these studies. Based on the epidemiological results, the analysis of the role of chance and bias, and the criteria for causal inferences, it seems that the evidence is not strong enough to support the putative causal relation between residential exposure to magnetic fields and adult leukaemia, brain tumours, or breast cancer. Inadequate statistical power is far more a concern than selection bias, information bias, and confounding in interpreting the results from these studies, and in explaining inconsistencies between studies. CONCLUSIONS: Our reviews suggested that the only way to answer whether residential exposure to magnetic fields is capable of increasing the risks of adult cancers is to conduct more studies carefully avoiding methodological flaws, in particular small sample size. We also suggested that the risk of female breast cancer should be the object of additional investigations, and that future studies should attempt to include information on exposure to magnetic fields from workplaces as well as residential exposure to estimate the effects of overall exposure to magnetic fields. PMID:8983460

  6. 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…

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

    PubMed Central

    Quist, Morten; Andersen, Christina; Møller, Tom; Herrstedt, Jørn; Kronborg, Dorte; Baadsgaard, Marie T; Vistisen, Kirsten; Midtgaard, Julie; Christiansen, Birgitte; Stage, Maria; Kronborg, Morten T; Rørth, Mikael

    2009-01-01

    Objective To assess the effect of a multimodal group exercise intervention, as an adjunct to conventional care, on fatigue, physical capacity, general wellbeing, physical activity, and quality of life in patients with cancer who were undergoing adjuvant chemotherapy or treatment for advanced disease. Design Randomised controlled trial. Setting Two university hospitals in Copenhagen, Denmark. Participants 269 patients with cancer; 73 men, 196 women, mean age 47 years (range 20-65) representing 21 diagnoses. Main exclusion criteria were brain or bone metastases. 235 patients completed follow-up. Intervention Supervised exercise comprising high intensity cardiovascular and resistance training, relaxation and body awareness training, massage, nine hours weekly for six weeks in addition to conventional care, compared with conventional care. Main outcome measures European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30), Medical Outcomes Study Short Form (MOS SF-36), Leisure Time Physical Activity Questionnaire, muscular strength (one repetition maximum), maximum oxygen consumption (Vo2max). Statistical methods The general linear model was used for continuous outcome while analysis of associates between categorical outcomes was performed as analysis of marginal homogeneity in contingency tables. Results Adjusted for baseline score, disease, and demographic covariates, the intervention group showed an estimated improvement at six weeks for the primary outcome, fatigue, of −6.6 points (95% confidence interval −12.3 to −0.9, P=0.02; effect size=0.33, 0.04 to 0.61). Significant effects were seen on vitality (effect size 0.55, 95% CI 0.27 to 0.82), physical functioning (0.37, 0.09 to 0.65), role physical (0.37, 0.10 to 0.64), role emotional (0.32, 0.05 to 0.59), and mental health (0.28, 0.02 to 0.56) scores. Improvement was noted in physical capacity: estimated mean difference between groups for maximum oxygen consumption

  8. Whole pelvic intensity-modulated radiotherapy for high-risk prostate cancer: a preliminary report

    PubMed Central

    Joo, Ji Hyeon; Kim, Yeon Joo; Choi, Eun Kyung; Kim, Jong Hoon; Lee, Sang-wook; Song, Si Yeol; Yoon, Sang Min; Kim, Su Ssan; Park, Jin-hong; Jeong, Yuri; Ahn, Hanjong; Kim, Choung-Soo; Lee, Jae-Lyun; Ahn, Seung Do

    2013-01-01

    Purpose To assess the clinical efficacy and toxicity of whole pelvic intensity-modulated radiotherapy (WP-IMRT) for high-risk prostate cancer. Materials and Methods Patients with high-risk prostate cancer treated between 2008 and 2013 were reviewed. The study included patients who had undergone WP-IMRT with image guidance using electronic portal imaging devices and/or cone-beam computed tomography. The endorectal balloon was used in 93% of patients. Patients received either 46 Gy to the whole pelvis plus a boost of up to 76 Gy to the prostate in 2 Gy daily fractions, or 44 Gy to the whole pelvis plus a boost of up to 72.6 Gy to the prostate in 2.2 Gy fractions. Results The study cohort included 70 patients, of whom 55 (78%) had a Gleason score of 8 to 10 and 50 (71%) had a prostate-specific antigen level > 20 ng/mL. The androgen deprivation therapy was combined in 62 patients. The biochemical failure-free survival rate was 86.7% at 2 years. Acute any grade gastrointestinal (GI) and genitourinary (GU) toxicity rates were 47% and 73%, respectively. The actuarial rate of late grade 2 or worse toxicity at 2 years was 12.9% for GI, and 5.7% for GU with no late grade 4 toxicity. Conclusion WP-IMRT was well tolerated with no severe acute or late toxicities, resulting in at least similar biochemical control to that of the historic control group with a small field. The long-term efficacy and toxicity will be assessed in the future, and a prospective randomized trial is needed to verify these findings. PMID:24501707

  9. 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.

  10. 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.

  11. Clinical Outcome of Adjuvant Treatment of Endometrial Cancer Using Aperture-Based Intensity-Modulated Radiotherapy

    SciTech Connect

    Bouchard, Myriam; Nadeau, Sylvain M.Sc.; Gingras, Luc; Raymond, Paul-Emile; Beaulieu, Frederic; Beaulieu, Luc; Fortin, Andre; Germain, Isabelle

    2008-08-01

    Purpose: To assess disease control and acute and chronic toxicity with aperture-based intensity-modulated radiotherapy (AB-IMRT) for postoperative pelvic irradiation of endometrial cancer. Methods and Materials: Between January and July 2005, after hysterectomy for endometrial cancer, 15 patients received 45 Gy to the pelvis using AB-IMRT. The AB-IMRT plans were generated by an in-house treatment planning system (Ballista). The AB-IMRT plans were used for treatment and were dosimetrically compared with three other approaches: conventional four-field, enlarged four-field, and beamlet-based IMRT (BB-IMRT). Disease control and toxicity were prospectively recorded and compared with retrospective data from 30 patients treated with a conventional four-field technique. Results: At a median follow-up of 27 months (range, 23-30), no relapse was noted among the AB-IMRT group compared with five relapses in the control group (p = 0.1). The characteristics of each group were similar, except for the mean body mass index, timing of brachytherapy, and applicator type used. Patients treated with AB-IMRT experienced more frequent Grade 2 or greater gastrointestinal acute toxicity (87% vs. 53%, p 0.02). No statistically significant difference was noted between the two groups regarding the incidence or severity of chronic toxicities. AB-IMRT plans significantly improved target coverage (93% vs. 76% of planning target volume receiving 45 Gy for AB-IMRT vs. conventional four-field technique, respectively). The sparing of organs at risk was similar to that of BB-IMRT. Conclusion: The results of our study have shown that AB-IMRT provides excellent disease control with equivalent late toxicity compared with the conventional four-field technique. AB-IMRT provided treatment delivery and quality assurance advantages compared with BB-IMRT and could reduce the risk of second malignancy compared with BB-IMRT.

  12. 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.

  13. Automated Weekly Replanning for Intensity-Modulated Radiotherapy of Cervix Cancer

    SciTech Connect

    Stewart, James

    2010-10-01

    Purpose: The adoption of intensity-modulated radiotherapy (IMRT) to treat cervical malignancies has been limited in part by complex organ and tumor motion during treatment. This study explores the limits of a highly adaptive, small-margin treatment scenario to accommodate this motion. In addition, the dosimetric consequences of organ and tumor motion are modeled using a combination of deformable registration and fractional dose accumulation techniques. Methods and Materials: Thirty-three cervix cancer patients had target volumes and organs-at-risk contoured on fused, pretreatment magnetic resonance-computed tomography images and weekly magnetic resonance scans taken during treatment. The dosimetric impact of interfraction organ and target motion was compared for two hypothetical treatment scenarios: a 3-mm margin plan with no replanning, and a 3-mm margin plan with an automated replan performed on the updated weekly patient geometry. Results: Of the 33 patients, 24 (73%) met clinically acceptable target coverage (98% of the clinical target volume receiving at least 95% of the prescription dose) using the 3-mm margin plan without replanning. The range in dose to 98% of the clinical target volume across all patients was 7.9% of the prescription dose if no replanning was performed. After weekly replanning, this range was tightened to 2.6% of the prescription dose and all patients met clinically acceptable target coverage while maintaining organ-at-risk dose sparing. Conclusions: The dosimetric impact of anatomical motion underscores the challenges of applying IMRT to treat cervix cancer. An appropriate adaptive strategy can ensure target coverage for small-margin IMRT treatments and maintain favorable organ-at-risk dose sparing.

  14. Low Intensity, High Frequency Vibration Training to Improve Musculoskeletal Function in a Mouse Model of Duchenne Muscular Dystrophy

    PubMed Central

    Novotny, Susan A.; Mader, Tara L.; Greising, Angela G.; Lin, Angela S.; Guldberg, Robert E.; Warren, Gordon L.; Lowe, Dawn A.

    2014-01-01

    The objective of the study was to determine if low intensity, high frequency vibration training impacted the musculoskeletal system in a mouse model of Duchenne muscular dystrophy, relative to healthy mice. Three-week old wildtype (n = 26) and mdx mice (n = 22) were randomized to non-vibrated or vibrated (45 Hz and 0.6 g, 15 min/d, 5 d/wk) groups. In vivo and ex vivo contractile function of the anterior crural and extensor digitorum longus muscles, respectively, were assessed following 8 wks of vibration. Mdx mice were injected 5 and 1 days prior to sacrifice with Calcein and Xylenol, respectively. Muscles were prepared for histological and triglyceride analyses and subcutaneous and visceral fat pads were excised and weighed. Tibial bones were dissected and analyzed by micro-computed tomography for trabecular morphometry at the metaphysis, and cortical geometry and density at the mid-diaphysis. Three-point bending tests were used to assess cortical bone mechanical properties and a subset of tibiae was processed for dynamic histomorphometry. Vibration training for 8 wks did not alter trabecular morphometry, dynamic histomorphometry, cortical geometry, or mechanical properties (P≥0.34). Vibration did not alter any measure of muscle contractile function (P≥0.12); however the preservation of muscle function and morphology in mdx mice indicates vibration is not deleterious to muscle lacking dystrophin. Vibrated mice had smaller subcutaneous fat pads (P = 0.03) and higher intramuscular triglyceride concentrations (P = 0.03). These data suggest that vibration training at 45 Hz and 0.6 g did not significantly impact the tibial bone and the surrounding musculature, but may influence fat distribution in mice. PMID:25121503

  15. Frequency of and Risk Factors for Acute Kidney Injury Associated With Vancomycin Use in the Pediatric Intensive Care Unit

    PubMed Central

    Bresee, Lauren C.; Kraft, Timothy; Ross, B. Catherine; Dersch-Mills, Deonne

    2016-01-01

    BACKGROUND: Published information evaluating frequency of and risk factors for vancomycin-induced acute kidney injury (AKI) in the pediatric intensive care unit (PICU) population is conflicting. OBJECTIVES: The primary objective was to describe the proportion of our PICU patients who developed AKI with intravenous (IV) vancomycin. The secondary objective was to describe the associated potential risk factors. METHODS: Pediatric patients (0–18 years) who received their first IV vancomycin dose in the PICU were evaluated in this retrospective chart review. AKI was defined based on Pediatric-Modified RIFLE (pRIFLE) criteria. Patient demographics, vancomycin trough concentrations, concomitant nephrotoxins, and estimated creatinine clearance changes were analyzed. RESULTS: Of 265 patients included, the primary outcome of AKI (defined by meeting any pRIFLE criteria) occurred in 62 (23.4%) patients (48 category R, 11 category I, 3 category F). Patients who received vancomycin treatment for = 5 days were more likely to develop AKI (unadjusted odds ratio [uOR]: 2.52; 95% confidence interval [CI]: 1.11–5.73), as were patients with a maximum vancomycin trough level = 20 mg/L (OR: 2.99; 95% CI: 1.54–5.78) and patients on 1 (uOR: 2.29; 95% CI: 1.12–4.66) or more concurrent nephrotoxin (uOR: 3.11; 95% CI: 1.43–6.77). Among nephrotoxins, patients receiving furosemide concomitantly with vancomycin were more likely to develop AKI (uOR: 3.47; 95% CI: 1.92–6.27). After adjustment, only furosemide was a significant predictor of risk of AKI/AKI (adjusted OR: 3.52; 95% CI: 1.88–6.62). The study was limited by its retrospective and observational design, and confounding variables. CONCLUSIONS: Patients who were receiving vancomycin with concurrent furosemide were at highest risk of developing AKI. PMID:28018150

  16. 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

  17. Low intensity, high frequency vibration training to improve musculoskeletal function in a mouse model of Duchenne muscular dystrophy.

    PubMed

    Novotny, Susan A; Mader, Tara L; Greising, Angela G; Lin, Angela S; Guldberg, Robert E; Warren, Gordon L; Lowe, Dawn A

    2014-01-01

    The objective of the study was to determine if low intensity, high frequency vibration training impacted the musculoskeletal system in a mouse model of Duchenne muscular dystrophy, relative to healthy mice. Three-week old wildtype (n = 26) and mdx mice (n = 22) were randomized to non-vibrated or vibrated (45 Hz and 0.6 g, 15 min/d, 5 d/wk) groups. In vivo and ex vivo contractile function of the anterior crural and extensor digitorum longus muscles, respectively, were assessed following 8 wks of vibration. Mdx mice were injected 5 and 1 days prior to sacrifice with Calcein and Xylenol, respectively. Muscles were prepared for histological and triglyceride analyses and subcutaneous and visceral fat pads were excised and weighed. Tibial bones were dissected and analyzed by micro-computed tomography for trabecular morphometry at the metaphysis, and cortical geometry and density at the mid-diaphysis. Three-point bending tests were used to assess cortical bone mechanical properties and a subset of tibiae was processed for dynamic histomorphometry. Vibration training for 8 wks did not alter trabecular morphometry, dynamic histomorphometry, cortical geometry, or mechanical properties (P ≥ 0.34). Vibration did not alter any measure of muscle contractile function (P ≥ 0.12); however the preservation of muscle function and morphology in mdx mice indicates vibration is not deleterious to muscle lacking dystrophin. Vibrated mice had smaller subcutaneous fat pads (P = 0.03) and higher intramuscular triglyceride concentrations (P = 0.03). These data suggest that vibration training at 45 Hz and 0.6 g did not significantly impact the tibial bone and the surrounding musculature, but may influence fat distribution in mice.

  18. 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

  19. Robust Intensity Modulated Proton Therapy (IMPT) Increases Estimated Clinical Benefit in Head and Neck Cancer Patients

    PubMed Central

    van Dijk, Lisanne V.; Steenbakkers, Roel J. H. M.; ten Haken, Bennie; van der Laan, Hans Paul; van ‘t Veld, Aart A.; Langendijk, Johannes A.; Korevaar, Erik W.

    2016-01-01

    Purpose To compare the clinical benefit of robust optimized Intensity Modulated Proton Therapy (minimax IMPT) with current photon Intensity Modulated Radiation Therapy (IMRT) and PTV-based IMPT for head and neck cancer (HNC) patients. The clinical benefit is quantified in terms of both Normal Tissue Complication Probability (NTCP) and target coverage in the case of setup and range errors. Methods and Materials For 10 HNC patients, PTV-based IMRT (7 fields), minimax and PTV-based IMPT (2, 3, 4, 5 and 7 fields) plans were tested on robustness. Robust optimized plans differed from PTV-based plans in that they target the CTV and penalize possible error scenarios, instead of using the static isotropic CTV-PTV margin. Perturbed dose distributions of all plans were acquired by simulating in total 8060 setup (±3.5 mm) and range error (±3%) combinations. NTCP models for xerostomia and dysphagia were used to predict the clinical benefit of IMPT versus IMRT. Results The robustness criterion was met in the IMRT and minimax IMPT plans in all error scenarios, but this was only the case in 1 of 40 PTV-based IMPT plans. Seven (out of 10) patients had relatively large NTCP reductions in minimax IMPT plans compared to IMRT. For these patients, xerostomia and dysphagia NTCP values were reduced by 17.0% (95% CI; 13.0–21.1) and 8.1% (95% CI; 4.9–11.2) on average with minimax IMPT. Increasing the number of fields did not contribute to plan robustness, but improved organ sparing. Conclusions The estimated clinical benefit in terms of NTCP of robust optimized (minimax) IMPT is greater than that of IMRT and PTV-based IMPT in HNC patients. Furthermore, the target coverage of minimax IMPT plans in the presence of errors was comparable to IMRT plans. PMID:27030987

  20. 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.

  1. Modulated single-bubble sonoluminescence: Dependence of phase of flashes, their intensity and rise/decay times on viscosity, the modulation strength, and frequency

    NASA Astrophysics Data System (ADS)

    Mastikhin, Igor; Djurkovic, Borko

    2004-05-01

    The single-bubble sonoluminescence (SBSL) signal was studied for the case of driving frequency modulated by lower frequency with an offset. In our work, the driving frequency of 28 kHz and the modulation frequencies of 25-1000 Hz were used. The modulation strength of 0.2, 0.5, and 0.8 was defined as the difference of highest and lowest pressures over modulation period. The measurements were performed for water-glycerol mixtures of various viscosities. The measured SBSL signal appeared as a train of flashes for modulation frequencies below 250 Hz, and as a continuous modulated signal for higher frequencies. At the same frequency, the flashes covered similar phase intervals for different modulation strengths and, accordingly, pressure ranges. At higher glycerol concentrations (up to 24%) both the intensity and the stability of flashes increased, due to damped shape instabilities and reduced dancing; however, the phase interval of flashes remained about the same. Such phase-locked behavior can be explained by translational movements of the bubble due to modulated Bjerknes force and changes in the symmetry of the bubble collapse. The changes in intensities and rise/decay times can serve as a measure of the gas exchange between the bubble and its surroundings during silent and luminescent intervals.

  2. 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.

  3. 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…

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. High-Intensity Focused Ultrasound for Prostate Cancer: Long-Term Followup and Complications Rate

    PubMed Central

    Maestroni, Umberto; Dinale, Francesco; Minari, Roberto; Salsi, Paolo; Ziglioli, Francesco

    2012-01-01

    Introduction. As it is well known, High Intensity Focused Ultrasound (HIFU) is a minimally invasive procedure for prostate cancer. Many investigators reported their series of patients, demonstrating the effectiveness of the treatment. The most majority of Authors, however, do not report the side effects and the complications of the procedure, which is the aim of our study. The diagnosis and management of complications is discussed, and the oncologic outcome is reported in terms of quality of life. Materials and Methods. We report our experience in 89 patients, low-, intermediate-, and high-risk patients according with D'Amico classification. All data collected along the study were analyzed, including side effects and complications of the procedure. Results. Our series demonstrates the effectiveness of the procedure, in line with larger series reported in literature by other investigators. The most important side effects are sexual function impairment and transient incontinence in a minority of cases. Minor complications are reported as well as rare cases of major complications, which can require surgical treatment. PMID:22927842

  10. High and low frequency subharmonic imaging of angiogenesis in a murine breast cancer model

    PubMed Central

    Dahibawkar, Manasi; Forsberg, Mark A.; Gupta, Aditi; Jaffe, Samantha; Dulin, Kelly; Eisenbrey, John R.; Halldorsdottir, Valgerdur G.; Forsberg, Anya I.; Dave, Jaydev K.; Marshall, Andrew; Machado, Priscilla; Fox, Traci B.; Liu, Ji-Bin; Forsberg, Flemming

    2015-01-01

    This project compared quantifiable measures of tumor vascularity obtained from contrast-enhanced high frequency (HF) and low frequency (LF) subharmonic ultrasound imaging (SHI) to 3 immunohistochemical markers of angiogenesis in a murine breast cancer model (since angiogenesis is an important marker of malignancy and the target of many novel cancer treatments). Nineteen athymic, nude, female rats were implanted with 5×106 breast cancer cells (MDA-MB-231) in the mammary fat pad. The contrast agent Definity (Lantheus Medical Imaging, N Billerica, MA) was injected in a tail vein (dose: 180µl/kg) and low frequency pulse-inversion SHI was performed with a modified Sonix RP scanner (Analogic Ultrasound, Richmond, BC, Canada) using a L9-4 linear array (transmitting/receiving at 8/4MHz in SHI mode) followed by high frequency imaging with a Vevo 2100 scanner (Visualsonics, Toronto, ON, Canada) using a MS250 linear array transmitting and receiving at 24MHz. The radiofrequency data was filtered using a 4th order IIR Butterworth bandpass filter (11–13MHz) to isolate the subharmonic signal. After the experiments, specimens were stained for endothelial cells (CD31), vascular endothelial growth factor (VEGF) and cyclooxygenase-2 (COX-2). Fractional tumor vascularity was calculated as contrast enhanced pixels over all tumor pixels for SHI, while the relative area stained over total tumor area was calculated from specimens. Results were compared using linear regression analysis. Out of 19 rats, 16 showed tumor growth (84%) and 11 of them were successfully imaged. HF SHI demonstrated better resolution, but weaker signals than LF SHI (0.06±0.017 vs. 0.39±0.059; p<0.001). The strongest overall correlation in this breast cancer model was between HF SHI and VEGF (r=−0.38; p=0.03). In conclusion, quantifiable measures of tumor neovascularity derived from contrast-enhanced HF SHI appear to be a better method than LF SHI for monitoring angiogenesis in a murine xenograft model of

  11. 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.

  12. A search for nitrosamines in East African spirit samples from areas of varying oesophageal cancer frequency

    PubMed Central

    Collis, C. H.; Cook, Paula J.; Foreman, J. K.; Palframan, J. F.

    1971-01-01

    Following the report of the presence of nitrosamine-like substances in samples of homemade spirit from Zambia, which had been obtained from an area where cancer of the oesophagus is common, samples of distilled alcoholic drinks were collected throughout western Kenya and southern Uganda from areas where the frequency of cancer of the oesophagus varies from very common to very rare. The 44 samples of spirit were screened by polarography and substances giving a similar response to nitrosamines were indicated at levels as high as 21 ppm. Subsequent analysis by gas chromatography for selected individual nitrosamines showed no evidence for the occurrence of methylethylnitrosamine (MEN), diethylnitrosamine (DEN), dipropylnitrosamine (DPN), ethylbutylnitrosamine (EBN), dibutylnitrosamine (DBN), nor of N nitrosopiperidine (N Pipn), but traces of compounds having a similar retention time as dimethylnitrosamine (DMN) were observed. However, subsequent examination by mass spectrometry showed no evidence of dimethylnitrosamine. There was no apparent association between the levels of unknown constituents indicated by polarography and gas chromatography, nor between either of these levels and the frequency of cancer of the oesophagus. The results by gas chromatography and mass spectrometry confirm that polarography is too unspecific to be a useful indicator of nitrosamines. PMID:5157131

  13. Influence of DNA-repair gene variants on the micronucleus frequency in thyroid cancer patients.

    PubMed

    García-Quispes, W A; Pastor, S; Galofré, P; Biarnés, F; Castell, J; Velázquez, A; Marcos, R

    2013-01-20

    The role of different DNA-repair genes (OGG1, XRCC1, XRCC2 and XRCC3) on both the spontaneous and the induced frequency of micronuclei (MN) has been studied in the lymphocytes of a group of 114 patients with differentiated thyroid cancer (DTC). Induction of MN was achieved by treatment of the lymphocytes with 0.5Gy of gamma-radiation. The selected genes are involved in base-excision repair (BER) (OGG1, Ser326Cys; XRCC1, Arg280His and Arg399Gln), and in homologous recombination repair (HRR) (XRCC2, Arg188His and XRCC3, IVS5-14G). Genotyping was carried out by use of the iPLEX (Sequenom) technique. Results indicate that only the OGG1-Ser326Cys polymorphism was able to modulate the MN frequency. This effect was only observed in the spontaneous MN frequency (P=0.016), but not in the MN frequency induced after irradiation. In addition, a strong correlation was observed between spontaneous and induced MN frequency, which would suggest an underlying genetic background.

  14. 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

  15. Development of a method of robust rain gauge network optimization based on intensity-duration-frequency results

    NASA Astrophysics Data System (ADS)

    Chebbi, A.; Bargaoui, Z. K.; da Conceição Cunha, M.

    2012-12-01

    Based on rainfall intensity-duration-frequency (IDF) curves, a robust optimization approach is proposed to identify the best locations to install new rain gauges. The advantage of robust optimization is that the resulting design solutions yield networks which behave acceptably under hydrological variability. Robust optimisation can overcome the problem of selecting representative rainfall events when building the optimization process. This paper reports an original approach based on Montana IDF model parameters. The latter are assumed to be geostatistical variables and their spatial interdependence is taken into account through the adoption of cross-variograms in the kriging process. The problem of optimally locating a fixed number of new monitoring stations based on an existing rain gauge network is addressed. The objective function is based on the mean spatial kriging variance and rainfall variogram structure using a variance-reduction method. Hydrological variability was taken into account by considering and implementing several return periods to define the robust objective function. Variance minimization is performed using a simulated annealing algorithm. In addition, knowledge of the time horizon is needed for the computation of the robust objective function. A short and a long term horizon were studied, and optimal networks are identified for each. The method developed is applied to north Tunisia (area = 21 000 km2). Data inputs for the variogram analysis were IDF curves provided by the hydrological bureau and available for 14 tipping bucket type rain gauges. The recording period was from 1962 to 2001, depending on the station. The study concerns an imaginary network augmentation based on the network configuration in 1973, which is a very significant year in Tunisia because there was an exceptional regional flood event in March 1973. This network consisted of 13 stations and did not meet World Meteorological Organization (WMO) recommendations for the minimum

  16. Development of a method of robust rain gauge network optimization based on intensity-duration-frequency results

    NASA Astrophysics Data System (ADS)

    Chebbi, A.; Bargaoui, Z. K.; da Conceição Cunha, M.

    2013-10-01

    Based on rainfall intensity-duration-frequency (IDF) curves, fitted in several locations of a given area, a robust optimization approach is proposed to identify the best locations to install new rain gauges. The advantage of robust optimization is that the resulting design solutions yield networks which behave acceptably under hydrological variability. Robust optimization can overcome the problem of selecting representative rainfall events when building the optimization process. This paper reports an original approach based on Montana IDF model parameters. The latter are assumed to be geostatistical variables, and their spatial interdependence is taken into account through the adoption of cross-variograms in the kriging process. The problem of optimally locating a fixed number of new monitoring stations based on an existing rain gauge network is addressed. The objective function is based on the mean spatial kriging variance and rainfall variogram structure using a variance-reduction method. Hydrological variability was taken into account by considering and implementing several return periods to define the robust objective function. Variance minimization is performed using a simulated annealing algorithm. In addition, knowledge of the time horizon is needed for the computation of the robust objective function. A short- and a long-term horizon were studied, and optimal networks are identified for each. The method developed is applied to north Tunisia (area = 21 000 km2). Data inputs for the variogram analysis were IDF curves provided by the hydrological bureau and available for 14 tipping bucket type rain gauges. The recording period was from 1962 to 2001, depending on the station. The study concerns an imaginary network augmentation based on the network configuration in 1973, which is a very significant year in Tunisia because there was an exceptional regional flood event in March 1973. This network consisted of 13 stations and did not meet World Meteorological

  17. Reduced frequency of extracolonic cancers in hereditary nonpolyposis colorectal cancer families with monoallelic hMLH1 expression.

    PubMed Central

    Jäger, A C; Bisgaard, M L; Myrhøj, T; Bernstein, I; Rehfeld, J F; Nielsen, F C

    1997-01-01

    Hereditary nonpolyposis colorectal cancer (HNPCC) is an autosomal dominant disease caused by mutations in one of at least four different DNA mismatch repair genes, hMLH1, hMSH2, hPMS1, and hPMS2. Phenotypically, HNPCC is characterized by the early onset of colorectal cancers and various extracolonic cancers. Depending on the presence or absence of extracolonic tumors, HNPCG-has been divided into two syndromes (Lynch syndrome I and Lynch syndrome II), but, so far, no correlation to distinct genotypes has been demonstrated. In this study, we present a frequent hMLH1 intron 14 founder mutation that is associated with a highly reduced frequency of extracolonic tumors. The mutation disrupts the splice donor site and silences the mutated allele. Tumors exhibited microsatellite instability, and loss of the wild-type hMLH1 allele was prevalent. We propose that the mutation results in a milder phenotype, because the mutated hMLH1 protein is prevented from exerting a dominant negative effect on the concerted action of the mismatch repair system. Images Figure 1 Figure 2 Figure 3 PMID:9245993

  18. Low-frequency phased-array 2D fluorescence localization in breast cancer detection

    NASA Astrophysics Data System (ADS)

    Liu, Qian; Chen, Yu; Chance, Britton; Luo, Qingming

    2003-12-01

    A method for rapid, non-invasive 2D fluorescence localization of breast cancer using low frequency phased array near-infrared technique is presented in this article. In our study, we have developed a dual-channel fluorescence detection system to locate breast cancer. This system consists two pair of in-phase and out-of-phase light emitting diodes (LEDs) as the light sources and Photomultiplier Tube (PMT) as the detector. Two null planes generated by cancellation of diffusion photon density waves (DPDW) will indicate the 2D position of breast cancer with exogenous contrast agents. The fluorescent contrast agent used in this study is Indocyanine Green (ICG) and the minimum amount of ICG detected by our system is 0.5 μM. With the 2 cm separation of sources and detector, the maximum depth our system can detect is 10 mm. The whole system is in compact size and portable. Phantom experiments show that the system can provide real time detection and localization of small hidden absorbing-fluorescent objects inside the highly scattering medium with high accuracy of +/-3 mm. The potential application is that it is low-cost and can be used for breast cancer localization as operation aid and self-examination.

  19. 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.

  20. Higher frequency but random distribution of EGFR mutation subtypes in familial lung cancer patients

    PubMed Central

    Hsu, Kuo-Hsuan; Tseng, Jeng-Sen; Wang, Chih-Liang; Yang, Tsung-Ying; Tseng, Chien-Hua; Chen, Hsuan-Yu; Chen, Kun-Chieh; Tsai, Chi-Ren; Yang, Cheng-Ta; Yu, Sung-Liang; Su, Kang-Yi; Yu, Chong-Jen; Ho, Chao-Chi; Hsia, Te-Chun; Wu, Ming-Fang; Chiu, Kuo-Liang; Liu, Chien-Ming; Yang, Pan-Chyr; Chen, Jeremy J.W.; Chang, Gee-Chen

    2016-01-01

    Despite the advancement of epidermal growth factor receptor (EGFR) inhibitors in lung cancer therapy, it remains unclear whether EGFR mutation status in familial lung cancers is different from that of sporadic cases. In this multicenter retrospective study, we compared both the EGFR mutation frequency and patterns between familial and sporadic cases. The results explored that family history of lung cancer is an independent predictor for higher EGFR mutation rate in 1713 lung adenocarcinoma patients (Odd ratio 1.68, 95% CI 1.06–2.67, P = 0.028). However, the distribution of EGFR mutation subtypes was similar to that of sporadic cases. Part of our study involved 40 lung cancer families with at least 2 tumor tissues available within each single family (n = 88) and there was no familial aggregation pattern in EGFR mutation subtypes. There were two families harboring the YAP1 R331W germline risk allele and EGFR mutation statuses among YAP1 family members also varied. These phenomena may hint at the direction of future research into lung carcinogenesis and EGFR mutagenesis. PMID:27449093

  1. [A successful treatment of percutaneous radio frequency ablation for advanced thyroid cancer].

    PubMed

    Miyabayashi, Chiharu; Ooiwa, Ako; Katakura, Masafumi; Ando, Takayuki; Hasumoto, Yuushi; Terao, Yumiko; Tsukada, Kenichirou; Kubota, Yoshiki; Nagai, Minoru; Neishi, Masao; Hara, Masahiro; Hashizume, Kiyoshi

    2005-10-01

    The patient was a 69-year-old woman. She received chemotherapy and radiation for thyroid tumor (undifferentiated cancer) following an operation in 1998. The chemotherapy was regularly repeated for relapse. The tumor increased gradually and came to cause dysphagia. She initially rejected nutritional management that depends on intravenous hyper alimentation or gastrostomy. After receiving an informed consent, we performed percutaneous radio frequency ablation (RFA) for the tumor using a Cool-tip needle on April 2, 2003. The algorithm of RFA was 9 min: 30 --> 120 W, 12 min: 50 --> 110 W, 9 min: 50 --> 100 W. After 2 days, the covered stent was implanted in the esophagus and an oral intake was started. Although the operation for undifferentiated thyroid cancer is controversial, we performed RFA and esophageal stenting for improving of QOL. This is the first case report in Japan.

  2. 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.

  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 Central

    Tan, Andy SL

    2014-01-01

    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. High-intensity interstitial ultrasound for thermal ablation of focal cancer targets in prostate

    NASA Astrophysics Data System (ADS)

    Salgaonkar, Vasant A.; Scott, Serena; Kurhanewicz, John; Diederich, Chris J.

    2017-03-01

    Recent advances in image based techniques such as multi-parametric MRI (MP-MRI) can provide precise targeting of focal disease in the prostate. Thermal ablation of such cancer targets while avoiding rectum, urethra, neurovascular bundles (NVB) and sphincter is clinically challenging. The approach described here employs multi-element ultrasound linear arrays designed for transperineal placement within prostate. They consist of independently powered sectored tubular transducers (6.5 - 8.0 MHz) that provide spatial control of energy deposition in angle and length. Volumetric ablation strategies were investigated through patient-specific biothermal models based on Pennes bioheat transfer equation. The acoustic and heat transfer models used here have been validated in several previous simulation and experimental studies. Focal disease sites in prostate were identified through multi-parametric MR images of representative patient cases (n=3). Focal cancer lesions and critical anatomy (prostate, urethra, rectum, bladder, seminal vesicles) were manually segmented (Mimics, Materialise) and converted to 3D finite element meshes (3-Matic, Materialise). The chosen test cases consisted of patients with medium and large sized glands and models of bulk tissue ablation covered volumes in a single quadrant in posterior prostate, hemi-gland targets and "hockey-stick" targets (lesions in three quadrants). Ultrasound applicator placement was determined such that devices were positioned along the prostate periphery while avoiding surrounding anatomy. Transducer sector angles were chosen based on applicator location within limits of fabrication practicability. Thermal models were numerically solved using finite element methods (FEM) in COMSOL Multiphysics. Temperature and thermal dose distributions were calculated to determine treated volumes (> 240 CEM43C, >52 °C) and safety profiles (<10 CEM43C, <45 °C) for nerve, rectal and urethral sparing. Modeling studies indicated that focal

  5. Esophageal Stenosis Associated With Tumor Regression in Radiotherapy for Esophageal Cancer: Frequency and Prediction

    SciTech Connect

    Atsumi, Kazushige; Shioyama, Yoshiyuki; Arimura, Hidetaka; Terashima, Kotaro; Matsuki, Takaomi; Ohga, Saiji; Yoshitake, Tadamasa; Nonoshita, Takeshi; Tsurumaru, Daisuke; Ohnishi, Kayoko; Asai, Kaori; Matsumoto, Keiji; Nakamura, Katsumasa; Honda, Hiroshi

    2012-04-01

    Purpose: To determine clinical factors for predicting the frequency and severity of esophageal stenosis associated with tumor regression in radiotherapy for esophageal cancer. Methods and Materials: The study group consisted of 109 patients with esophageal cancer of T1-4 and Stage I-III who were treated with definitive radiotherapy and achieved a complete response of their primary lesion at Kyushu University Hospital between January 1998 and December 2007. Esophageal stenosis was evaluated using esophagographic images within 3 months after completion of radiotherapy. We investigated the correlation between esophageal stenosis after radiotherapy and each of the clinical factors with regard to tumors and therapy. For validation of the correlative factors for esophageal stenosis, an artificial neural network was used to predict the esophageal stenotic ratio. Results: Esophageal stenosis tended to be more severe and more frequent in T3-4 cases than in T1-2 cases. Esophageal stenosis in cases with full circumference involvement tended to be more severe and more frequent than that in cases without full circumference involvement. Increases in wall thickness tended to be associated with increases in esophageal stenosis severity and frequency. In the multivariate analysis, T stage, extent of involved circumference, and wall thickness of the tumor region were significantly correlated to esophageal stenosis (p = 0.031, p < 0.0001, and p = 0.0011, respectively). The esophageal stenotic ratio predicted by the artificial neural network, which learned these three factors, was significantly correlated to the actual observed stenotic ratio, with a correlation coefficient of 0.864 (p < 0.001). Conclusion: Our study suggested that T stage, extent of involved circumference, and esophageal wall thickness of the tumor region were useful to predict the frequency and severity of esophageal stenosis associated with tumor regression in radiotherapy for esophageal cancer.

  6. 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

  7. 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

  8. 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.

  9. 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.

  10. Intensity-modulated radiotherapy reduces gastrointestinal toxicity in locally advanced pancreas cancer

    PubMed Central

    Prasad, Shreya; Cambridge, Lajhem; Huguet, Florence; Chou, Joanne F.; Zhang, Zhigang; Wu, Abraham J.; O'Reilly, Eileen M.; Allen, Peter; Goodman, Karyn A.

    2016-01-01

    Purpose We compared gastrointestinal (GI) and hematologic toxicity in patients with locally advanced pancreas cancer (LAPC) undergoing definitive chemoradiation using intensity modulated radiotherapy (IMRT) or 3D conformal radiotherapy (3D-CRT) planning. Methods and Materials We retrospectively studied 205 patients with LAPC undergoing IMRT (n=134) and 3D-CRT (n=71) between 05/03 and 03/12. Patient, tumor, and treatment characteristics and acute GI/hematology toxicity according to Common Terminology Criteria for Adverse Events v3.0 were recorded. Multivariable logistic regression models were used to test association between acute grade 2+ GI and hematologic toxicity outcomes and predictors. Propensity score analysis for grade 2+ GI toxicity was performed to reduce bias for confounding variables: age, gender, radiation dose, field size, and chemotherapy type. Results Median follow-up time for survivors was 22 months, similar between groups. Median RT dose was significantly higher for IMRT vs. 3D-CRT (5600 cGy vs 5040 cGy, P<.001); concurrent chemotherapy was mainly gemcitabine (56%) or 5-fluorouracil (5-FU, 38%). Grade 2+ GI toxicity occurred in 34% (n=24) of 3D-CRT compared with 16% (n=21) of IMRT patients. Using propensity-score analysis, 3D-CRT had significantly higher grade 2+ GI toxicity (odds ratio, 1.26 [95%CI, 1.08-1.45], P=.001). Grade 2+ hematologic toxicity was similar between IMRT and 3D-CRT groups but was significantly greater in recipients of concurrent gemcitabine over 5-FU (62% vs 29%, P<.0001). Conclusions IMRT is associated with significant lower grade 2+ GI toxicity versus 3D-CRT for patients undergoing definitive chemoradiotherapy for LAPC. Since IMRT is better tolerated at higher doses and may allow further dose escalation, potentially improving local control for this aggressive disease. Further prospective studies of dose-escalated chemoradiation using IMRT are warranted. PMID:26577010

  11. 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.

  12. Intensity-modulated radiation therapy (IMRT) in the treatment of anal cancer: Toxicity and clinical outcome

    SciTech Connect

    Milano, Michael T.; Jani, Ashesh B.; Farrey, Karl J.; Rash, Carla C.; Heimann, Ruth; Chmura, Steven J. . E-mail: schmura@radonc.uchicago.edu

    2005-10-01

    Purpose: To assess survival, local control, and toxicity of intensity modulated radiation therapy (IMRT) in squamous cell carcinoma of the anal canal. Methods and Materials: Seventeen patients were treated with nine-field IMRT plans. Thirteen received concurrent 5-fluorouracil and mitomycin C, whereas 1 patient received 5-fluorouracil alone. Seven patients were planned with three-dimensional anteroposterior/posterior-anterior (AP/PA) fields for dosimetric comparison to IMRT. Results: Compared with AP/PA, IMRT reduced the mean and threshold doses to small bowel, bladder, and genitalia. Treatment was well tolerated, with no Grade {>=}3 acute nonhematologic toxicity. There were no treatment breaks attributable to gastrointestinal or skin toxicity. Of patients who received mitomycin C, 38% experienced Grade 4 hematologic toxicity. IMRT did not afford bone marrow sparing, possibly resulting from the clinical decision to prescribe 45 Gy to the whole pelvis in most patients, vs. the Radiation Therapy Oncology Group-recommended 30.6 Gy whole pelvic dose. Three of 17 patients, who did not achieve a complete response, proceeded to an abdominoperineal resection and colostomy. At a median follow-up of 20.3 months, there were no other local failures. Two-year overall survival, disease-free survival, and colostomy-free survival are: 91%, 65%, and 82% respectively. Conclusions: In this hypothesis-generating analysis, the acute toxicity and clinical outcome with IMRT in the treatment of anal cancer is encouraging. Compared with historical controls, local control is not compromised despite efforts to increase conformality and reduce normal structure dose.

  13. 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.

  14. 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.

  15. 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.

  16. Effects of pain education program on pain intensity, pain treatment satisfaction, and barriers in Turkish cancer patients.

    PubMed

    Yildirim, Yasemin Kuzeyli; Cicek, Fadiloglu; Uyar, Meltem

    2009-12-01

    The purpose of this randomized controlled study was to investigate the effect of a pain education program (PEP) on pain intensity, patients' satisfaction with pain treatment, and patient-related barriers to pain management among Turkish patients with cancer. The study was conducted in a sample of 40 patients who were hospitalized for cancer and experiencing pain. The patients were equally randomized to either a PEP or a control group. The data were collected by means of the McGill Pain Questionnaire, the Numeric Rating Scale, and the Barrier Questionnaire-Revised. After the completion of the questionnaires at the first interview, patients in the PEP group received pain education using a pain educational booklet and an explanatory slide program that discussed the booklet's content with the patients. Patients in the control group received routine clinical care. The questionnaires were reapplied to the patients in both groups after 2, 4, and 8 weeks. Participation in a PEP was associated with decreased pain intensity scores for "present" and "least pain" during weeks 2, 4, and 8 (p < .05). Similarly, there were significant differences between the groups with respect to weeks 2, 4, and 8 satisfaction with pain treatment (p < .05). At the end of second week, the total BQ-r score decreased significantly in the PEP group from 2.12 to 1.29 compared with 2.30 to 2.28 in the control group (p < .001). The findings suggest that the PEP decreases pain intensity, improves satisfaction with treatment, and decreases barriers about cancer pain management in cancer patients. Incorparation of PEP into the standard of care for cancer patients with pain may improve the quality of pain management.

  17. 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

  18. 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.

  19. Calculation of the fundamental vibrational frequencies and intensities of H2, D2, and N2 in the presence of Li(+) or Na

    NASA Astrophysics Data System (ADS)

    Bishop, David M.; Cybulski, Slawomir M.

    1994-11-01

    Self-consistent-field (SCF) and second-order Moller-Plesset (MP2) calculations, using large basis sets, have been carried out for the system X2...Y(+), with X = H, D, and N and Y = Li and Na. In particular, the fundamental vibrational frequency shifts and intensities induced in the diatomic by the cation have been found. For Y = Na these properties may be compared with the experimental infrared spectra of the same diatomics when trapped in a NaA zeolite. There is good agreement between theory and experiment for the frequency shifts but the calculated intensity for N2...Na(+) is several times larger than that found in the zeolite. This indicates that either the model for the trapped species is too simple or the experimental result needs reassessment.

  20. On the consideration of scaling properties of extreme rainfall in Madrid (Spain) for developing a generalized intensity-duration-frequency equation and assessing probable maximum precipitation estimates

    NASA Astrophysics Data System (ADS)

    Casas-Castillo, M. Carmen; Rodríguez-Solà, Raúl; Navarro, Xavier; Russo, Beniamino; Lastra, Antonio; González, Paula; Redaño, Angel

    2016-11-01

    The fractal behavior of extreme rainfall intensities registered between 1940 and 2012 by the Retiro Observatory of Madrid (Spain) has been examined, and a simple scaling regime ranging from 25 min to 3 days of duration has been identified. Thus, an intensity-duration-frequency (IDF) master equation of the location has been constructed in terms of the simple scaling formulation. The scaling behavior of probable maximum precipitation (PMP) for durations between 5 min and 24 h has also been verified. For the statistical estimation of the PMP, an envelope curve of the frequency factor (k m ) based on a total of 10,194 station-years of annual maximum rainfall from 258 stations in Spain has been developed. This curve could be useful to estimate suitable values of PMP at any point of the Iberian Peninsula from basic statistical parameters (mean and standard deviation) of its rainfall series.

  1. Extremely low frequency electric and magnetic fields and cancer: A literature review

    SciTech Connect

    Creasey, W.A.; Goldberg, R.B. )

    1989-12-01

    Epidemiologic studies suggest a weak link between occupational or residential exposure to extremely low frequency electromagnetic fields and cancer, especially tumors of the central nervous and hematopoietic systems. This report discusses these studies with reference to basic research on ELF EMF bioeffects relevant to cancer-promoting mechanisms. Many of the studies suggest a possible interaction of ELF EMF with the immune system, endocrine system, or growth-regulatory signals and morphogenic movements that involve calcium flux through cell membranes. Many bioeffects have been reported only with certain specific combinations of frequency, amplitude, and orientation of the EMF signal with respect to the geomagnetic field. The possibility of signal-specific effects raises a complication in dosimetry for both epidemiologic and experimental studies since ELF EMF effects may not be directly related to field strength. The report concludes with a discussion of design considerations for ELF EMF exposure systems to be used in animal experiments. Original abstracts of selected references are included in an appendix. 260 refs., 1 fig., 1 tab.

  2. Characterization of thyroid cancer in mouse models using high-frequency quantitative ultrasound techniques.

    PubMed

    Lavarello, Roberto J; Ridgway, William R; Sarwate, Sandhya S; Oelze, Michael L

    2013-12-01

    Currently, the evaluation of thyroid cancer relies on the use of fine-needle aspiration biopsy, as non-invasive imaging methods do not provide sufficient levels of accuracy for the diagnosis of this disease. In this study, the potential of quantitative ultrasound methods for characterization of thyroid tissues was studied using a rodent model ex vivo. A high-frequency ultrasonic scanning system (40 MHz) was used to scan thyroids extracted from mice that had spontaneously developed thyroid lesions (cancerous or benign). Three sets of mice were acquired having different predispositions to developing three thyroid anomalies: C-cell adenoma, papillary thyroid carcinoma (PTC) and follicular variant papillary thyroid carcinoma (FV-PTC). A fourth set of mice that did not develop thyroid anomalies (normal mice) were used as controls. The backscatter coefficient was estimated from excised thyroid lobes the different mice. From the backscatter coefficient versus frequency (25-45 MHz), the effective scatterer diameter (ESD) and effective acoustic concentration (EAC) were estimated. From the envelope of the backscattered signal, the homodyned K distribution was used to estimate the k parameter (ratio of coherent to incoherent signal energy) and the μ parameter (number of scatterers per resolution cell). Statistically significant differences were observed between cancerous thyroids and normal thyroids based on the ESD, EAC and μ parameters. The mean ESD values were 18.0 ± 0.92, 15.9 ± 0.81 and 21.5 ± 1.80 μm for the PTC, FV-PTC and normal thyroids, respectively. The mean EAC values were 59.4 ± 1.74, 62.7 ± 1.61 and 52.9 ± 3.42 dB (mm(-3)) for the PTC, FV-PTC and normal thyroids, respectively. The mean μ values were 2.55 ± 0.37, 2.59 ± 0.43 and 1.56 ± 0.99 for the PTC, FV-PTC and normal thyroids, respectively. Statistically significant differences were observed between cancerous thyroids and C-cell adenomas based on the ESD and EAC parameters, with an estimated ESD

  3. 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.

  4. 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.

  5. High and low frequency subharmonic imaging of angiogenesis in a murine breast cancer model.

    PubMed

    Dahibawkar, Manasi; Forsberg, Mark A; Gupta, Aditi; Jaffe, Samantha; Dulin, Kelly; Eisenbrey, John R; Halldorsdottir, Valgerdur G; Forsberg, Anya I; Dave, Jaydev K; Marshall, Andrew; Machado, Priscilla; Fox, Traci B; Liu, Ji-Bin; Forsberg, Flemming

    2015-09-01

    This project compared quantifiable measures of tumor vascularity obtained from contrast-enhanced high frequency (HF) and low frequency (LF) subharmonic ultrasound imaging (SHI) to 3 immunohistochemical markers of angiogenesis in a murine breast cancer model (since angiogenesis is an important marker of malignancy and the target of many novel cancer treatments). Nineteen athymic, nude, female rats were implanted with 5×10(6) breast cancer cells (MDA-MB-231) in the mammary fat pad. The contrast agent Definity (Lantheus Medical Imaging, N Billerica, MA) was injected in a tail vein (dose: 180μl/kg) and LF pulse-inversion SHI was performed with a modified Sonix RP scanner (Analogic Ultrasound, Richmond, BC, Canada) using a L9-4 linear array (transmitting/receiving at 8/4MHz in SHI mode) followed by HF imaging with a Vevo 2100 scanner (Visualsonics, Toronto, ON, Canada) using a MS250 linear array transmitting and receiving at 24MHz. The radiofrequency data was filtered using a 4th order IIR Butterworth bandpass filter (11-13MHz) to isolate the subharmonic signal. After the experiments, specimens were stained for endothelial cells (CD31), vascular endothelial growth factor (VEGF) and cyclooxygenase-2 (COX-2). Fractional tumor vascularity was calculated as contrast-enhanced pixels over all tumor pixels for SHI, while the relative area stained over total tumor area was calculated from specimens. Results were compared using linear regression analysis. Out of 19 rats, 16 showed tumor growth (84%) and 11 of them were successfully imaged. HF SHI demonstrated better resolution, but weaker signals than LF SHI (0.06±0.017 vs. 0.39±0.059; p<0.001). The strongest overall correlation in this breast cancer model was between HF SHI and VEGF (r=-0.38; p=0.03). In conclusion, quantifiable measures of tumor neovascularity derived from contrast-enhanced HF SHI appear to be a better method than LF SHI for monitoring angiogenesis in a murine xenograft model of breast cancer

  6. 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.

  7. The effects of different intensities, frequencies and exposure times of extremely low-frequency electromagnetic fields on the growth of Staphylococcus aureus and Escherichia coli O157:H7.

    PubMed

    Bayır, Ece; Bilgi, Eyüp; Şendemir-Ürkmez, Aylin; Hameş-Kocabaş, E Esin

    2015-03-01

    The impact of different types of extremely low-frequency electromagnetic fields (ELF-EMF) on the growth of Staphylococcus aureus and Escherichia coli O157:H7 was investigated. The cultures of bacteria in broth media were exposed to sinusoidal homogenous ELF-EMF with 2 and 4 mT magnetic intensities. Each intensity for each bacteria was combined with three different frequencies (20, 40 and 50 Hz), and four different exposure times (1, 2, 4 and 6 h). A cell suspension of each experiment was diluted for the appropriate range and inoculated to Mueller-Hinton Agar (MHA) plates after exposure to ELF-EMF. The number of colony forming units (CFU) of both strains was obtained after incubation at 37 °C for 24 h. Data were statistically evaluated by one-way analysis of variance (ANOVA), statistical significance was described at p < 0.05 and data were compared with their non-exposed controls. Magnetic intensity, frequency and exposure time of ELF-EMFs changed the characteristic responses for both microorganisms. Samples exposed to ELF-EMF showed a statistically significant decrease compared to their controls in colony forming capability, especially at long exposure times. An exposure to 4 mT-20 Hz ELF-EMF of 6 h produced maximum inhibition of CFU compared to their controls for both microorganisms (95.2% for S. aureus and 85% for E. coli).

  8. 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

  9. 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.

  10. Larynx-sparing techniques using intensity-modulated radiation therapy for oropharyngeal cancer.

    PubMed

    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.

  11. 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.

  12. 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

  13. Postoperative Intensity Modulated Radiation Therapy in High Risk Prostate Cancer: A Dosimetric Comparison

    SciTech Connect

    Digesu, 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

    2011-10-01

    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.

  14. 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.

  15. 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.

  16. [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.

  17. 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.

  18. 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.

  19. 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

  20. 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

  1. 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.

  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. 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

  4. Thermoacoustic Contrast of Prostate Cancer due to Heating by Very High Frequency Irradiation

    PubMed Central

    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 thermoacoustic 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. PMID:25554968

  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. 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.

  8. Proton-beam vs intensity-modulated radiation therapy. Which is best for treating prostate cancer?

    PubMed

    Nguyen, Paul L; Trofimov, Alexei; Zietman, Anthony L

    2008-06-01

    There is a growing interest in the use of proton therapy for the treatment of many cancers. With its unique dose-distribution properties, proton therapy has the potential to improve the therapeutic ratio of prostate radiation by allowing for an increase in dose without a substantial increase in side effects. While much evidence supports this notion in the context of many oncologic sites, only limited clinical data have compared protons to photons in prostate cancer. Therefore, the increasing enthusiasm for the use of protons in prostate cancer has aroused considerable concern. Some have questioned its ability to limit morbidity, and others have questioned its value relative to the cost. In addition, theoretical concerns have been raised about a potential additional risk for secondary malignancies. In this article, we review the current status of the evidence supporting the use of protons in prostate cancer and discuss the active controversies that surround this modality.

  9. [Frequency of chronic bronchitis in an intensely polluted urban zone. Preliminary results in children. Analysis of the implicated factors].

    PubMed

    Bungeţianu, G; Radu, G; Opriş, C; Păltineanu, V; Ruşdea, N; Cresco, F; Silaghi, I

    1980-01-01

    The starting point is that environment factors induce chronic bronchitis in adults and children and that the disease in adult is a consequence of respiratory tree susceptibility which might be better evidenced during childhood. The authors have studied a group of children aged 0--14 years in a highly air-poluted workers' quarter in the city of Baia-Mare. The frequence of chronic bronchitis was 10.3% with higher values in children below 5 years and over 10 years, the age group 5--9 years being a group with higher resistance to this disease. The figures are three times higher in boys than in girls, on possible endogenous factors. The girls could be, however, more subjected to "passive smoking" because of smokers presence in family and in bed room. The number of children in a family did not correlate with chronic bronchitis frequence. This frequence was significantly influenced by allergic and ear-nose-throat phenomena in the history, more evidently in 0--4 years and 10-14 years groups of age. These elements could be thus considered as risk factors. They also indicate the place to be acted upon in order to prevent chronic bronchitis in children.

  10. Feasibility demonstration of frequency domain terahertz imaging in breast cancer margin determination.

    PubMed

    Yngvesson, Sigfrid K; St Peter, Benjamin; Siqueira, Paul; Kelly, Patrick; Glick, Stephen; Karellas, Andrew; Khan, Ashraf

    2012-02-09

    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.

  11. Handheld low-frequency phased array near-infrared (NIR) breast cancer localizer

    NASA Astrophysics Data System (ADS)

    Liu, Qian; Chen, Yu; Luo, Qingming

    2003-07-01

    A system for rapid and precise localization of breast cancer using low frequency phased array near-infrared technique has been developed. In this system, in-phase and out-of-phase of sine-wave signals at 3 kHz modulate two light emitting diode (LED) sources respectively. And amplitude cancellation of two photon density waves will occur in the silicon-detector at the mid-plane of two sources reference. Cancellation signal is displayed by an embedded amplitude and phase detector and is displayed acoustically. The whole system is pocket-size, handheld with the dimension of 6.0cm×5.0cm×2.5cm and the weight is 140g. Experiments with phantom and animals show that the system can provide real time detection and localization of small hidden absorbing-fluorescent objects inside the highly scattering medium at the depth of 2cm with high accuracy of +/-1 ~ 2mm. The limit of object detection with 20 mA LED current is 1cm and with 40 mA is 2cm. The potential application is that it can be used for early breast cancer detection as a convenient self-examination device.

  12. Fatal deep vein thrombosis after allogeneic reduced intensity hematopoietic stem cell transplantation for the treatment of metastatic gastric cancer.

    PubMed

    Kamitsuji, Yuri; Mori, Shin-Ichiro; Kami, Masahiro; Yamada, Hirofumi; Shirakawa, Kazuo; Kishi, Yukiko; Murashige, Naoko; Kim, Sung-Won; Heike, Yuji; Takaue, Yoichi

    2004-08-01

    A 61-year-old man received reduced intensity stem cell transplantation (RIST) for the treatment of metastatic gastric cancer. The cytoreductive course of RIST was uneventful until day 0, when fever suddenly developed and his performance status deteriorated. Edema developed in the bilateral lower extremities by day 7, which was diagnosed by Doppler ultrasonography as deep vein thrombosis (DVT) involving the femoral veins to the inferior vena cava. While the edema improved with anticoagulation treatment, gastrointestinal graft-versus-host disease (GVHD) followed on day 13. Diarrhea subsided spontaneously, but hypoalbuminemia persisted, with the subsequent development of oliguria and jaundice on day 18. He died of sepsis on day 30, without any evidence of cancer progression. This case demonstrates that DVT is a potentially significant problem following RIST for solid tumors.

  13. Homogeneous and inhomogeneous broadenings and the Voigt line shapes in the phase-resolved and intensity sum-frequency generation vibrational spectroscopy

    SciTech Connect

    Chen, Shunli; Fu, Li; Gan, Wei; Wang, Hongfei

    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 (HR-BB-SFG-VS) 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 for the first time the direct comparison and understanding of the homogeneous and inhomogeneous broadenings in the imaginary and intensity SFG vibrational spectral lineshapes in detail. The difference of the full width at half maxima (FWHM) of the imaginary and intensity SFG-VS spectra of the same vibrational mode is the signature of the Voigt lineshape and it measures the relative contribution to the overall lineshape 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 lineshape with a homogeneous broadening half width of Γ = 5.29 ± 0.08 cm-1 and a inhomogeneous standard derivation width Δω = 5.42 ± 0.07 cm-1. These results shed new lights on the understanding and interpretation of the lineshapes of both the phase-resolved and the intensity SFG vibrational spectra, as well as other incoherent and coherent spectroscopic techniques in general.

  14. Low frequency KRAS mutations in colorectal cancer patients and the presence of multiple mutations in oncogenic drivers in non-small cell lung cancer patients.

    PubMed

    Jiang, Liyan; Huang, Jiaqi; Morehouse, Chris; Zhu, Wei; Korolevich, Susana; Sui, Dan; Ge, Xiaoxiao; Lehmann, Kim; Liu, Zheng; Kiefer, Christine; Czapiga, Meggan; Su, Xinying; Brohawn, Philip; Gu, Yi; Higgs, Brandon W; Yao, Yihong

    2013-01-01

    Intratumor heterogeneity can confound the results of mutation analyses in oncodriver genes using traditional methods thereby challenging the application of targeted cancer therapy strategies for patients Ultradeep sequencing can detect low frequency and expanded clonal mutations in primary tumors to better inform treatment decisions. KRAS coding exons in 61 treatment-naive colorectal cancer (CRC) tumors and KRAS, EGFR, ALK, and MET in lung tumors from three Chinese non-small cell lung cancer (NSCLC) patients were sequenced using ultradeep sequencing methods. Forty-one percent of CRC patients (25/61) harbored mutations in the KRAS active domain, eight of which (13%) were not detected by Sanger sequencing. Three (of eight) had frequencies less than 10% and one patient harbored more than one mutation. Low frequency KRAS active (G12R) and EGFR kinase domain mutations (G719A) were identified in one NSCLC patient. A second NSCLC patient showed an EML4-ALK fusion with ALK, EGFR, and MET mutations. A third NSCLC patient harbored multiple low frequency mutations in KRAS, EGFR, and MET as well as ALK gene copy number increases. Within the same patient, multiple low frequency mutations occurred within a gene. A complex pattern of intrinsic low frequency driver mutations in well-known tumor oncogenes may exist prior to treatment, resulting in resistance to targeted therapies. Ultradeep sequencing can characterize intratumor heterogeneity and identify such mutations to ultimately affect treatment decisions.

  15. Lazarus response to treatment of patients with lung cancer and oncogenic mutations in the intensive care unit

    PubMed Central

    Chien, Chun-Ru

    2016-01-01

    Novel targeted therapy for patients with non-small-cell lung cancer (NSCLC) and oncogenic mutations along with poor performance status (PS) sometimes evokes a “Lazarus” response. Moreover, for critically ill patients with NSCLC and respiratory failure requiring mechanical ventilation (MV) in the intensive care unit (ICU), only a few case reports have demonstrated positive outcomes with targeted therapy. This perspective review describes in detail the most recently published data in order to highlight the findings and the main pitfalls of targeted therapy for patients with NSCLC in the ICU. PMID:28066630

  16. [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.

  17. Delayed intensive care unit admission is associated with increased mortality in patients with cancer with acute respiratory failure.

    PubMed

    Mokart, Djamel; Lambert, Jérôme; Schnell, David; Fouché, Louis; Rabbat, Antoine; Kouatchet, Achille; Lemiale, Virginie; Vincent, François; Lengliné, Etienne; Bruneel, Fabrice; Pene, Frederic; Chevret, Sylvie; Azoulay, Elie

    2013-08-01

    Acute respiratory failure (ARF) is the leading reason for intensive care unit (ICU) admission in patients with cancer. The aim of this study was to identify early predictors of death in patients with cancer admitted to the ICU for ARF who were not intubated at admission. We conducted analysis of a prospective randomized controlled trial including 219 patients with cancer with ARF in which day-28 mortality was a secondary endpoint. Mortality at day 28 was 31.1%. By multivariate analysis, independent predictors of day-28 mortality were: age (odds ratio [OR] 1.30/10 years, 95% confidence interval [CI] [1.01-1.68], p = 0.04), more than one line of chemotherapy (OR 2.14, 95% CI [1.08-4.21], p = 0.03), time between respiratory symptoms onset and ICU admission > 2 days (OR 2.50, 95% CI [1.25-5.02], p = 0.01), oxygen flow at admission (OR 1.07/L, 95% CI [1.00-1.14], p = 0.04) and extra-respiratory symptoms (OR 2.84, 95%CI [1.30-6.21], p = 0.01). After adjustment for the logistic organ dysfunction (LOD) score at admission, only time between respiratory symptoms onset and ICU admission > 2 days and LOD score were independently associated with day-28 mortality. Determinants of death include both factors non-amenable to change, and delay in ARF management. These results suggest that early intensive care management of patients with cancer with ARF may translate to better survival.

  18. 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.

  19. 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.

  20. 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

  1. Characterization of thyroid cancer in mouse models using high-frequency quantitative ultrasound techniques

    PubMed Central

    Lavarello, R. J.; Ridgway, W. R.; Sarwate, S.; Oelze, M. L.

    2013-01-01

    Currently, the evaluation of thyroid cancer relies on the use of fine needle aspiration biopsy as non-invasive imaging methods do not provide sufficient levels of accuracy for the diagnosis of this disease. In this study, the potential of quantitative ultrasound methods for characterizing thyroid tissues was studied using a rodent model ex vivo. A high-frequency ultrasonic scanning system (40 MHz) was used to scan thyroids extracted from mice that had spontaneously developed thyroid lesions (cancerous or benign). Three sets of mice were acquired having different predispositions to developing thyroid anomalies (a C-cell adenoma, a papillary thyroid carcinoma (PTC), and a follicular variant papillary thyroid carcinoma (FV-PTC)). A fourth set of mice did not develop thyroid anomalies (normal mice) and were used as controls. The backscatter coefficient was estimated from excised thyroid lobes for the different mice. From the backscatter coefficient versus frequency (25 to 45 MHz), the effective scatterer diameter (ESD) and effective acoustic concentration (EAC) were estimated. From the envelope of the backscattered signal, the homodyned K distribution was used to estimate the k parameter (ratio of coherent to incoherent signal energy) and the μ parameter (number of scatterers per resolution cell). Statistically significant differences were observed between the malignant thyroids and the normal thyroids based on the ESD, EAC and μ parameters. The mean values of the ESDs were 18.0 ± 0.92, 15.9 ± 0.81, and 21.5 ± 1.80 µm for the PTC, FV-PTC and the normal thyroids, respectively. The mean values of the EACs were 59.4 ± 1.74, 62.7 ± 1.61, and 52.9 ± 3.42 dB (mm−3) for the PTC, FV-PTC and the normal thyroids, respectively. The mean values of the μ parameters were 2.55 ± 0.37, 2.59 ± 0.43, and 1.56 ± 0.99 for the PTC, FV-PTC and the normal thyroids, respectively. Statistically significant differences were observed between the malignant thyroids and the C

  2. Exome genotyping arrays to identify rare and low frequency variants associated with epithelial ovarian cancer risk.

    PubMed

    Permuth, Jennifer B; Pirie, Ailith; Ann Chen, Y; Lin, Hui-Yi; Reid, Brett M; Chen, Zhihua; Monteiro, Alvaro; Dennis, Joe; Mendoza-Fandino, Gustavo; Anton-Culver, Hoda; Bandera, Elisa V; Bisogna, Maria; Brinton, Louise; Brooks-Wilson, Angela; Carney, Michael E; Chenevix-Trench, Georgia; Cook, Linda S; Cramer, Daniel W; Cunningham, Julie M; Cybulski, Cezary; D'Aloisio, Aimee A; Anne Doherty, Jennifer; Earp, Madalene; Edwards, Robert P; Fridley, Brooke L; Gayther, Simon A; Gentry-Maharaj, Aleksandra; Goodman, Marc T; Gronwald, Jacek; Hogdall, Estrid; Iversen, Edwin S; Jakubowska, Anna; Jensen, Allan; Karlan, Beth Y; Kelemen, Linda E; Kjaer, Suzanne K; Kraft, Peter; Le, Nhu D; Levine, Douglas A; Lissowska, Jolanta; Lubinski, Jan; Matsuo, Keitaro; Menon, Usha; Modugno, Rosemary; Moysich, Kirsten B; Nakanishi, Toru; Ness, Roberta B; Olson, Sara; Orlow, Irene; Pearce, Celeste L; Pejovic, Tanja; Poole, Elizabeth M; Ramus, Susan J; Anne Rossing, Mary; Sandler, Dale P; Shu, Xiao-Ou; Song, Honglin; Taylor, Jack A; Teo, Soo-Hwang; Terry, Kathryn L; Thompson, Pamela J; Tworoger, Shelley S; Webb, Penelope M; Wentzensen, Nicolas; Wilkens, Lynne R; Winham, Stacey; Woo, Yin-Ling; Wu, Anna H; Yang, Hannah; Zheng, Wei; Ziogas, Argyrios; Phelan, Catherine M; Schildkraut, Joellen M; Berchuck, Andrew; Goode, Ellen L; Pharoah, Paul D P; Sellers, Thomas A

    2016-08-15

    Rare and low frequency variants are not well covered in most germline genotyping arrays and are understudied in relation to epithelial ovarian cancer (EOC) risk. To address this gap, we used genotyping arrays targeting rarer protein-coding variation in 8,165 EOC cases and 11,619 controls from the international Ovarian Cancer Association Consortium (OCAC). Pooled association analyses were conducted at the variant and gene level for 98,543 variants directly genotyped through two exome genotyping projects. Only common variants that represent or are in strong linkage disequilibrium (LD) with previously-identified signals at established loci reached traditional thresholds for exome-wide significance (P < 5.0 × 10 (-)  (7)). One of the most significant signals (Pall histologies = 1.01 × 10 (-)  (13);Pserous = 3.54 × 10 (-)  (14)) occurred at 3q25.31 for rs62273959, a missense variant mapping to the LEKR1 gene that is in LD (r(2 )=( )0.90) with a previously identified 'best hit' (rs7651446) mapping to an intron of TIPARP. Suggestive associations (5.0 × 10 (-)  (5 )>( )P≥5.0 ×10 (-)  (7)) were detected for rare and low-frequency variants at 16 novel loci. Four rare missense variants were identified (ACTBL2 rs73757391 (5q11.2), BTD rs200337373 (3p25.1), KRT13 rs150321809 (17q21.2) and MC2R rs104894658 (18p11.21)), but only MC2R rs104894668 had a large effect size (OR = 9.66). Genes most strongly associated with EOC risk included ACTBL2 (PAML = 3.23 × 10 (-)  (5); PSKAT-o = 9.23 × 10 (-)  (4)) and KRT13 (PAML = 1.67 × 10 (-)  (4); PSKAT-o = 1.07 × 10 (-)  (5)), reaffirming variant-level analysis. In summary, this large study identified several rare and low-frequency variants and genes that may contribute to EOC susceptibility, albeit with possible small effects. Future studies that integrate epidemiology, sequencing, and functional assays are needed to further

  3. 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.

  4. [The effects of electromagnetic radiation of extremely high frequency and low intensity on the growth rate of bacteria Escherichia coli and the role of medium pH].

    PubMed

    Tadevosian, A; Kalantarian, V; Trchunian, A

    2007-01-01

    It has been shown that coherent electromagnetic irradiation (EMI) of extremely high frequency (45-53 GHz) or millimeter waves (wavelength 5.6-6.7 mm) of low intensity (flux capacity 0.06 mW/cm2) of Escherichia coli K12, grown under anaerobic conditions during the fermentation of sugar (glucose) for 30 min or 1 h, caused a decrease in their growth rate, the maximum inhibitory effect being achieved at a frequency of 51.8 or 53 GHz. This effect depended on medium pH when the maximal action was determined at pH 7.5. In addition, separate 30-min of 1-h irradiation (frequency 51.8 or 53 GHz) of doubly distilled water or some inorganic ions contained in Tris-phosphate buffer where the cells were transferred induced oppositely directed changes in further growth of these bacteria under anaerobic conditions; irradiation of water caused a decrease in the growth rate of bacteria. A significant change in pH of water (0.5-1.5 unit) was induced by a 30-irradiation at a frequency of 49, 50.3, 51.8, or 53 GHz, when the initial pH value was 6.0 or 8.0, but not 7.5. These results indicate the changes in the properties of water and its role in the effects of EMI of extremely high frequency. The marked effect of EMI on bacteria disappeared upon repeated irradiation for 1 h at a frequency of 51.8 or 53 GHz with an interval of 2 hours. This result indicates some compensatory mechanisms in bacteria.

  5. 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.

  6. 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.

  7. 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

  8. Non-Thermal High-Intensity Focused Ultrasound for Breast Cancer Therapy

    DTIC Science & Technology

    2013-07-01

    AVAILABILITY STATEMENT Approved for Public Release; Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Several in vitro studies have...is not affected by the local biochemical environment and shows less radiation resistance. However, there have been no in vivo animal studies ...potential normal tissue toxicities, if any, associated with non-thermal HIFU treatment for breast cancer. Extensive phantom studies have been completed

  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. Frequency of 5382insC mutation of BRCA1 gene among breast cancer patients: an experience from Eastern India.

    PubMed

    Chakraborty, Abhijit; Mukhopadhyay, Ashis; Bhattacharyya, Deboshree; Bose, Chinmoy Kr; Choudhuri, Keya; Mukhopadhyay, Soma; Basak, Jayasri

    2013-09-01

    The incidence of breast cancer in India is on the rise and is rapidly becoming the number one cancer in females pushing the cervical cancer to the second position. The mutations in two breast cancer susceptibility genes, BRCA1 and BRCA2, are frequently associated with familial breast cancer. The main objective of the study was to determine the frequency of the mutation 5382insC in BRCA1 of eastern Indian breast cancer patients and also study the hormonal receptor status and histopathology of the patients. Altogether 92 patients affected with breast cancer were included in this study. ARMS-PCR based amplification was used to detect the presence of mutation. The mutations were considered only after pedigree analysis. Out of 92 patients (age range: 20-77 years) with family history (57 individuals) and without family history (35 individuals) were screened. Fifty controls have been systematically investigated. Seven patients and two family members were found to be carriers of 5382insC mutation in BRCA1 gene. We have found 42.64 % ER(-)/PR(-) cancer and 20.58 % triple negative cancer. Invasive ductal carcinoma is the most common histology among the investigated individuals. The presented data confirm a noticeable contribution of BRCA1 5382insC mutation in BC development in Eastern India, which may justify an extended BRCA1 5382insC testing within this patient population. We found HER-2/neu negativity and BRCA1 positivity associated with familial breast cancer. From the hospital's patient history, it was revealed that the age of menarche plays an important role in development of breast cancer.

  11. Greater intensity and frequency of Cryptosporidium and Giardia oocyst shedding beyond the neonatal period is associated with reductions in growth, carcase weight and dressing efficiency in sheep.

    PubMed

    Jacobson, Caroline; Williams, Andrew; Yang, Rongchang; Ryan, Una; Carmichael, Ian; Campbell, Angus J; Gardner, Graham E

    2016-09-15

    Associations between intensity and frequency of Cryptosporidium and Giardia shedding with growth, carcase weight and dressing% were investigated using a longitudinal study of 1182 lambs on eight Australian farms. Live weight was recorded and faecal samples were collected on three sampling occasions; weaning (approximately 12 weeks of age), post-weaning (approximately 19 weeks) and pre-slaughter (approximately 29 weeks). Hot standard carcase weight (HSCW) and dressing% were measured at slaughter. Faecal samples were screened for presence and concentration of Cryptosporidium, Giardia and Haemonchus oocysts using a quantitative PCR. Trichostrongylid eggs were quantified with modified McMaster faecal worm egg count (WEC). Protozoan shedding intensity was categorised as high (above median oocyst concentration in positive sheep), low (below median oocyst concentration in positive sheep) or not detected. Shedding was also categorised for shedding type (no shedding, single Giardia infection, single Cryptosporidium infection, concurrent Giardia and Cryptosporidium infection) and lambs were categorised for frequency of shedding (shedding identified on 0, 1, 2 or 3 occasions). Associations of parasite shedding intensity category, shedding type, shedding frequency, WEC and Haemonchus status (positive or negative) with lamb production were assessed using general linear models (HSCW and dressing%) and linear mixed effects models (live weight). High Cryptosporidium parvum shedding was associated with lower live weight, ranging 2.31-4.52kg over the 3 sampling occasions. Cryptosporidium parvum shedding was associated with less HSCW in high (3.22kg less) and low (3.22kg less) shedding lambs post-weaning, and high (2.21kg less) and low (2.60kg less) shedding lambs pre-slaughter as well as lower dressing% (2.7% lower in high shedding lambs post-weaning). Cryptosporidium (all species) shedding pre-slaughter was associated with reduced dressing% in both high (1.25% lower) and low (1

  12. 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.

  13. 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.

  14. 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

  15. 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.

  16. Frequency of Early-Stage Lymphedema and Risk Factors in Postoperative Patients with Breast Cancer

    PubMed Central

    Soyder, Aykut; Taştaban, Engin; Özbaş, Serdar; Boylu, Şükrü; Özgün, Hedef

    2014-01-01

    Objective Lymphedema is a chronic major complication that is seen frequently post-operatively and has negative effects on quality of life. In our study, determining the early-stage postoperative lymphedema frequency and specifying the risk factors in its development has been aimed. Materials and Methods One hundred one cases that were operated on for breast cancer were evaluated regarding the 12-month control of their clinical specifications, histopathological specifications, and specifications related with the surgical intervention retrospectively. The data related to the parameters envisioned as risk factors were evaluated. Results Lymphedema development was found in 7 (6.9%) out of 101 cases constituting the study group. No significant difference (p>0.05) in terms of lymphedema development was determined among age, body mass index (BMI), chemotherapy (CT), postoperative seroma or infection, mastectomy with the dominant arm, and breast-conserving surgery (BCS), which were evaluated as risk factors. There was a significance (p<0.05) between the other risk factors, which were axillary dissection (AD), number of positive lymph nodes (LN), radiotherapy (RT), the tumor size (T), and lymphedema existence. In every case in which lymphedema was determined, it was seen that there was axillary LN involvement and 15≤LN were ablated in the dissection (p<0.05). Conclusion It is seen that AD, RT applied to the breast cancer patients, and T are important risk factors in early-stage lymphedema development. No early-stage lymphedema development was determined in any of the patients to whom sentinel lymph node dissection (SLND) was applied.

  17. Development of a simplified, mass producible hybridized ambient, low frequency, low intensity vibration energy scavenger (half-lives)

    NASA Astrophysics Data System (ADS)

    Khbeis, Michael Tawfik

    Scavenging energy from environmental sources is an active area of research to enable remote sensing and microsystems applications. Furthermore, as energy demands soar, there is a significant need to explore new sources and curb waste. Vibration energy scavenging is one environmental source for remote applications and a candidate for recouping energy wasted by mechanical sources that can be harnessed to monitor and optimize operation of critical infrastructure (e.g. Smart Grid). Current vibration scavengers are limited by volume and ancillary requirements for operation such as control circuitry overhead and battery sources. This dissertation, for the first time, reports a mass producible hybrid energy scavenger system that employs both piezoelectric and electrostatic transduction on a common MEMS device. The piezoelectric component provides an inherent feedback signal and pre-charge source that enables electrostatic scavenging operation while the electrostatic device provides the proof mass that enables low frequency operation. The piezoelectric beam forms the spring of the resonant mass-spring transducer for converting vibration excitation into an AC electrical output. A serially poled, composite shim, piezoelectric bimorph produces the highest output rectified voltage of over 3.3V and power output of 145muW using ¼ g vibration acceleration at 120Hz. Considering solely the volume of the piezoelectric beam and tungsten proof mass, the volume is 0.054cm3, resulting in a power density of 2.68mW/cm3. Incorporation of a simple parallel plate structure that provides the proof mass for low frequency resonant operation in addition to cogeneration via electrostatic energy scavenging provides a 19.82 to 35.29 percent increase in voltage beyond the piezoelectric generated DC rails. This corresponds to approximately 2.1nW additional power from the electrostatic scavenger component and demonstrates the first instance of hybrid energy scavenging using both piezoelectric and

  18. SU-E-T-07: 4DCT Robust Optimization for Esophageal Cancer Using Intensity Modulated Proton Therapy

    SciTech Connect

    Liao, L; Yu, J; Zhu, X; Li, H; Zhang, X; Li, Y; Lim, G

    2015-06-15

    Purpose: To develop a 4DCT robust optimization method to reduce the dosimetric impact from respiratory motion in intensity modulated proton therapy (IMPT) for esophageal cancer. Methods: Four esophageal cancer patients were selected for this study. The different phases of CT from a set of 4DCT were incorporated into the worst-case dose distribution robust optimization algorithm. 4DCT robust treatment plans were designed and compared with the conventional non-robust plans. Result doses were calculated on the average and maximum inhale/exhale phases of 4DCT. Dose volume histogram (DVH) band graphic and ΔD95%, ΔD98%, ΔD5%, ΔD2% of CTV between different phases were used to evaluate the robustness of the plans. Results: Compare to the IMPT plans optimized using conventional methods, the 4DCT robust IMPT plans can achieve the same quality in nominal cases, while yield a better robustness to breathing motion. The mean ΔD95%, ΔD98%, ΔD5% and ΔD2% of CTV are 6%, 3.2%, 0.9% and 1% for the robustly optimized plans vs. 16.2%, 11.8%, 1.6% and 3.3% from the conventional non-robust plans. Conclusion: A 4DCT robust optimization method was proposed for esophageal cancer using IMPT. We demonstrate that the 4DCT robust optimization can mitigate the dose deviation caused by the diaphragm motion.

  19. Effects of tumor type, degree of obesity, and chemotherapy regimen on chemotherapy dose intensity in obese cancer patients.

    PubMed

    Miyahara, T; Mochinaga, S; Kimura, S; Aragane, N; Yakabe, T; Morita, S; Okudaira, K; Fujito, H

    2013-01-01

    The American Society of Clinical Oncology recently published a Clinical Practice Guideline entitled "Appropriate Chemotherapy Dosing for Obesity Adult Patients with Cancer." The panel recommended that full weight (actual weight)-based cytotoxic chemotherapy doses are used to treat obese patients with cancer, particularly when the goal of treatment is cure. However, no study has examined dosage calculation methods used for obese cancer patients in Japan. Here, we retrospectively studied the relationships between chemotherapy dose intensity, the occurrence of adverse events, and treatment outcomes in obese patients undergoing chemotherapy. Patients were divided into two groups: the actual BW group (BWg) was composed of patients receiving dosage amounts calculated using their actual BW (n = 64), and the ideal BWg was composed of patients receiving dosage amounts calculated using their ideal BW (n = 41). There were significant differences in the incidence of Grade 3/4 hematological toxicity in the actual and ideal BWg in solid tumor patients, but not in patients with hematological malignancies. In solid tumor patients with ≥30 body mass index (BMI), the incidence of Grade 3/4 hematological toxicity was significantly lower in the ideal BWg than in the actual BWg. Particularly, in patients with complications, incidence of Grade 4 hematological toxicity was significantly higher in the actual BWg than in the ideal BWg. These results suggest that the tumor type, degree of obesity, complications, and choice of chemotherapy regimen should be considered when determining chemotherapy dosage for obese patients.

  20. Assessment of histopathological features of needle biopsy in recurrent prostate cancer following salvage high-intensity focused ultrasound

    PubMed Central

    Billia, Michele; Siddiqui, Khurram M.; Chan, Susanne; Li, Fan; Al-Zahrani, Ali; Gomez, Jose A.; Chin, Joseph L.

    2016-01-01

    Introduction Local recurrence of prostate cancer (PCa) following radiotherapy may be treated with curative intent using salvage high-intensity focused ultrasound (s-HIFU). The interpretation of needle core biopsy specimens following s-HIFU is a daunting task, even for experienced pathologists. We describe various histopathological features encountered in biopsy specimens following whole-gland s-HIFU in one of the largest descriptive studies to date. Methods Fifty-five patients with biopsy-proven localized radio-recurrent PCa underwent s-HIFU and transrectal ultrasound (TRUS)-guided prostatic needle biopsies at 180 days post-treatment. All biopsies were reviewed by two genitourinary pathologists. Results PCa was detected in 11 (24%) biopsies. Radiation therapy-associated changes were identified in all cases. Additional findings included extensive coagulative stromal necrosis (100%), smudgy chromatin of cancer nuclei (82%), and markedly enlarged bizarre nuclei in the residual cancer (55%). Gleason grade assignment was possible in 10 (91%) of these biopsies and concordance of Gleason grading between pre- and post-therapy specimens was observed in six (60%) cases. Conclusions The histological interpretation of needle biopsies following salvage HIFU is challenging and requires an understanding of the histopathological changes associated with this procedure in both tumoural and non-tumoural prostatic tissue. Accurate interpretation of the morphological changes following s-HIFU is instrumental for optimization of clinical decision-making and treatment planning in recurrent PCa. PMID:28096917

  1. Regional intensity-duration-frequency analysis in the Eastern Black Sea Basin, Turkey, by using L-moments and regression analysis

    NASA Astrophysics Data System (ADS)

    Ghiaei, Farhad; Kankal, Murat; Anilan, Tugce; Yuksek, Omer

    2016-10-01

    The analysis of rainfall frequency is an important step in hydrology and water resources engineering. However, a lack of measuring stations, short duration of statistical periods, and unreliable outliers are among the most important problems when designing hydrology projects. In this study, regional rainfall analysis based on L-moments was used to overcome these problems in the Eastern Black Sea Basin (EBSB) of Turkey. The L-moments technique was applied at all stages of the regional analysis, including determining homogeneous regions, in addition to fitting and estimating parameters from appropriate distribution functions in each homogeneous region. We studied annual maximum rainfall height values of various durations (5 min to 24 h) from seven rain gauge stations located in the EBSB in Turkey, which have gauging periods of 39 to 70 years. Homogeneity of the region was evaluated by using L-moments. The goodness-of-fit criterion for each distribution was defined as the ZDIST statistics, depending on various distributions, including generalized logistic (GLO), generalized extreme value (GEV), generalized normal (GNO), Pearson type 3 (PE3), and generalized Pareto (GPA). GLO and GEV determined the best distributions for short (5 to 30 min) and long (1 to 24 h) period data, respectively. Based on the distribution functions, the governing equations were extracted for calculation of intensities of 2, 5, 25, 50, 100, 250, and 500 years return periods (T). Subsequently, the T values for different rainfall intensities were estimated using data quantifying maximum amount of rainfall at different times. Using these T values, duration, altitude, latitude, and longitude values were used as independent variables in a regression model of the data. The determination coefficient (R 2) value indicated that the model yields suitable results for the regional relationship of intensity-duration-frequency (IDF), which is necessary for the design of hydraulic structures in small and

  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. Estimation of intensity-duration-frequency relationships according to the property of scale invariance and regionalization analysis in a Mediterranean coastal area

    NASA Astrophysics Data System (ADS)

    Ghanmi, Hanen; Bargaoui, Zoubeida; Mallet, Cécile

    2016-10-01

    Usually, networks of daily rainfall raingauges have a higher spatial cover than tippet bucket raingauges networks. Consequently, it would be of high interest to make use of daily rainfall information to asses IDF curves for unobserved locations. The present work proposes achieving this goal by using the assumption of simple scaling invariance. Indeed, series observed over sufficiently long periods for 10 tippet bucket raingauge, allowed us to test the hypothesis of simple scaling of annual maximum rainfall intensities in northern Tunisia. This assumption, combined with Gumbel model of maximum rainfall intensities allowed us to develop a methodology to estimate IDF curves from the daily rainfall totals. In fact, a regionalization formula which involves the percentile 90% of the annual maximum daily rainfall was developed and validated. This regionalization formula applied to daily data of 25 rainfall stations in the sub area of Tunis region, combined with the assumption of simple scaling has enabled us to develop Intensity Duration Area Frequency (IDAF) curves for Tunis area.

  4. Assessment of the intensity-duration-frequency (IDF) curves for storms in Peninsular Malaysia based on the generalized extreme value distribution

    NASA Astrophysics Data System (ADS)

    Mohd Ariff, Noratiqah; Jemain, Abdul Aziz; Wan Zin, Wan Zawiah

    2013-04-01

    Rainfall characteristics can be analyzed by using storm events with storms representing actual rainfall events instead of rainfall amounts in fixed time frames. One of the most commonly used methods in rainfall analysis is the construction of intensity-duration-frequency (IDF) curves. IDF curves help in designing hydraulic structures by providing a mathematical relationship between storm intensity, duration and return period. In Peninsular Malaysia, these curves are often built using the generalized extreme value (GEV) distribution to represent annual maximum storm intensity. The mathematical formula for the curves is usually taken from either known empirical equations or from quantile functions of probability distributions. However, there is no research which compares and analyzes the differences between the curves obtained for storms in Peninsular Malaysia based on the empirical and quantile functions. Thus, the aim of this study is to build IDF curves for storms in Peninsular Malaysia using typical empirical equations and the quantile function of the GEV distribution. Then, the analysis of differences is performed on the curves obtained from both approaches. The analysis consists of the coefficient of variation of root mean square error mean percentage difference and the coefficient of determination, R2. The analysis shows small differences between the curves based on the empirical equations and those obtained using the quantile function of GEV distribution. According to these results, it can be concluded that the simple empirical equations are sufficient in constructing IDF curves based on GEV distribution for storms in Peninsular Malaysia.

  5. Rainfall extremes, excesses, and intensity-duration-frequency curves: A unified asymptotic framework and new nonasymptotic results based on multifractal measures

    NASA Astrophysics Data System (ADS)

    Veneziano, Daniele; Yoon, Seonkyoo

    2013-07-01

    We present a unified asymptotic theory of rainfall extremes including annual maxima, excesses above high thresholds, and intensity-duration-frequency (IDF) curves that builds on previous findings and derive new nonasymptotic results. The analysis is based on stationary multifractal representations of rainfall and produces extensions of the familiar results from extreme value (EV) and extreme excess (EE) theories. The latter results apply to the T-yr maximum as T→∞ and the excess above z as z→∞. By exploiting the scaling relationship among the distributions of rainfall intensity for different averaging durations d, the multifractal asymptotics include, in addition, results in the small-scale limits d→0 and >(d→0,T∝d-α→∞>) with α > 0. In all cases, the maximum distributions are of the generalized extreme value (GEV) type, but the index k depends on the limit considered. Multifractal models also produce asymptotic scaling results for the IDF curves. For the nonasymptotic case (d and T finite), we obtain accurate approximations of the IDF curves and derive a semitheoretical formula for the index k of the GEV model that best approximates the distribution of the annual maximum over a finite range of return-period intensities. The nonasymptotic analysis explains several observed deviations of rainfall extremes from the asymptotic predictions, such as the tendency of k to decrease as the averaging duration d increases and the tendency of the IDF curves to converge as d or the return period T increase.

  6. Positron Emission Tomography/Computed Tomography-Guided Intensity-Modulated Radiotherapy for Limited-Stage Small-Cell Lung Cancer

    SciTech Connect

    Shirvani, Shervin M.; Komaki, Ritsuko; Heymach, John V.; Fossella, Frank V.

    2012-01-01

    Purpose: Omitting elective nodal irradiation from planning target volumes does not compromise outcomes in patients with non-small-cell lung cancer, but whether the same is true for those with limited-stage small-cell lung cancer (LS-SCLC) is unknown. Therefore, in the present study, we sought to determine the clinical outcomes and the frequency of elective nodal failure in patients with LS-SCLC staged using positron emission tomography/computed tomography and treated with involved-field intensity-modulated radiotherapy. Methods and Materials: Between 2005 and 2008, 60 patients with LS-SCLC at our institution underwent disease staging using positron emission tomography/computed tomography before treatment using an intensity-modulated radiotherapy plan in which elective nodal irradiation was intentionally omitted from the planning target volume (mode and median dose, 45 Gy in 30 fractions; range, 40.5 Gy in 27 fractions to 63.8 Gy in 35 fractions). In most cases, concurrent platinum-based chemotherapy was administered. We retrospectively reviewed the clinical outcomes to determine the overall survival, relapse-free survival, and failure patterns. Elective nodal failure was defined as recurrence in initially uninvolved hilar, mediastinal, or supraclavicular nodes. Survival was assessed using the Kaplan-Meier method. Results: The median age of the study patients at diagnosis was 63 years (range, 39-86). The median follow-up duration was 21 months (range, 4-58) in all patients and 26 months (range, 4-58) in the survivors. The 2-year actuarial overall survival and relapse-free survival rate were 58% and 43%, respectively. Of the 30 patients with recurrence, 23 had metastatic disease and 7 had locoregional failure. We observed only one isolated elective nodal failure. Conclusions: To our knowledge, this is the first study to examine the outcomes in patients with LS-SCLC staged with positron emission tomography/computed tomography and treated with definitive intensity

  7. 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

  8. Climate change is projected to have severe impacts on the frequency and intensity of peak electricity demand across the United States.

    PubMed

    Auffhammer, Maximilian; Baylis, Patrick; Hausman, Catherine H

    2017-02-21

    It has been suggested that climate change impacts on the electric sector will account for the majority of global economic damages by the end of the current century and beyond [Rose S, et al. (2014) Understanding the Social Cost of Carbon: A Technical Assessment]. The empirical literature has shown significant increases in climate-driven impacts on overall consumption, yet has not focused on the cost implications of the increased intensity and frequency of extreme events driving peak demand, which is the highest load observed in a period. We use comprehensive, high-frequency data at the level of load balancing authorities to parameterize the relationship between average or peak electricity demand and temperature for a major economy. Using statistical models, we analyze multiyear data from 166 load balancing authorities in the United States. We couple the estimated temperature response functions for total daily consumption and daily peak load with 18 downscaled global climate models (GCMs) to simulate climate change-driven impacts on both outcomes. We show moderate and heterogeneous changes in consumption, with an average increase of 2.8% by end of century. The results of our peak load simulations, however, suggest significant increases in the intensity and frequency of peak events throughout the United States, assuming today's technology and electricity market fundamentals. As the electricity grid is built to endure maximum load, our findings have significant implications for the construction of costly peak generating capacity, suggesting additional peak capacity costs of up to 180 billion dollars by the end of the century under business-as-usual.

  9. Climate change is projected to have severe impacts on the frequency and intensity of peak electricity demand across the United States

    PubMed Central

    Auffhammer, Maximilian; Baylis, Patrick; Hausman, Catherine H.

    2017-01-01

    It has been suggested that climate change impacts on the electric sector will account for the majority of global economic damages by the end of the current century and beyond [Rose S, et al. (2014) Understanding the Social Cost of Carbon: A Technical Assessment]. The empirical literature has shown significant increases in climate-driven impacts on overall consumption, yet has not focused on the cost implications of the increased intensity and frequency of extreme events driving peak demand, which is the highest load observed in a period. We use comprehensive, high-frequency data at the level of load balancing authorities to parameterize the relationship between average or peak electricity demand and temperature for a major economy. Using statistical models, we analyze multiyear data from 166 load balancing authorities in the United States. We couple the estimated temperature response functions for total daily consumption and daily peak load with 18 downscaled global climate models (GCMs) to simulate climate change-driven impacts on both outcomes. We show moderate and heterogeneous changes in consumption, with an average increase of 2.8% by end of century. The results of our peak load simulations, however, suggest significant increases in the intensity and frequency of peak events throughout the United States, assuming today’s technology and electricity market fundamentals. As the electricity grid is built to endure maximum load, our findings have significant implications for the construction of costly peak generating capacity, suggesting additional peak capacity costs of up to 180 billion dollars by the end of the century under business-as-usual. PMID:28167756

  10. Low intensity ultrasound induces apoptosis via MPT channel on mitochondrial membrane: Target for regulating cancer therapy or not?

    NASA Astrophysics Data System (ADS)

    Feng, Yi; Wan, Mingxi

    2017-03-01

    To discuss how the mitochondrion is involved in low intensity ultrasound induced apoptosis, HepG2 cells were irradiated by low intensity focused ultrasound (ISPTA = 3W/cm2, 1 min) and then cultured from 3-12 h post irradiation in the study. The morphological alteration was examined by light and fluorescent microscopy respectively. Cell viability and apoptosis were examined by trypan blue staining and flow cytometry with double staining of FITC-labelled Annexin-V/PI. Key proteins responded to irradiation were screened out by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and shotgun proteomic methods with Agilent 1100 HPLC-Chip-MS technology. Representative apoptotic morphological characteristics and increased percentage of apoptotic cells were achieved. Six important proteins (4 up-regulated and 2 down-regulated) were selected and analyzed. It revealed low intensity focused ultrasound could induce apoptosis in HepG2 cells and the US-induced apoptosis was mitochondria-dependent and caspases-dependent. Moreover, mitochondrial membrane permeability transition (MPT) is related to ultrasound induced apoptosis, but VDAC may be not the main MPT channel. Understanding it could help to assist the cancer therapy by regulating the MPT as the target.

  11. 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.

  12. Geostatistical analysis of disease data: estimation of cancer mortality risk from empirical frequencies using Poisson kriging

    PubMed Central

    Goovaerts, Pierre

    2005-01-01

    Background Cancer mortality maps are used by public health officials to identify areas of excess and to guide surveillance and control activities. Quality of decision-making thus relies on an accurate quantification of risks from observed rates which can be very unreliable when computed from sparsely populated geographical units or recorded for minority populations. This paper presents a geostatistical methodology that accounts for spatially varying population sizes and spatial patterns in the processing of cancer mortality data. Simulation studies are conducted to compare the performances of Poisson kriging to a few simple smoothers (i.e. population-weighted estimators and empirical Bayes smoothers) under different scenarios for the disease frequency, the population size, and the spatial pattern of risk. A public-domain executable with example datasets is provided. Results The analysis of age-adjusted mortality rates for breast and cervix cancers illustrated some key features of commonly used smoothing techniques. Because of the small weight assigned to the rate observed over the entity being smoothed (kernel weight), the population-weighted average leads to risk maps that show little variability. Other techniques assign larger and similar kernel weights but they use a different piece of auxiliary information in the prediction: global or local means for global or local empirical Bayes smoothers, and spatial combination of surrounding rates for the geostatistical estimator. Simulation studies indicated that Poisson kriging outperforms other approaches for most scenarios, with a clear benefit when the risk values are spatially correlated. Global empirical Bayes smoothers provide more accurate predictions under the least frequent scenario of spatially random risk. Conclusion The approach presented in this paper enables researchers to incorporate the pattern of spatial dependence of mortality rates into the mapping of risk values and the quantification of the

  13. Non-thermal High-intensity Focused Ultrasound for Breast Cancer Therapy

    DTIC Science & Technology

    2012-07-01

    Form 298 (Rev. 8-98) Prescribed by ANSI Std. Z39.18 Several in vitro studies have demonstrated the non-thermal (< 42 ºC) cell killing effect of HIFU...radiation resistance. However, there have been no in vivo animal studies performed on non-thermal HIFU to demonstrate its therapeutic potential. This...associated with non-thermal HIFU treatment for breast cancer. Extensive phantom studies have been completed to determine suitable ultrasound parameters for

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. Noninvasive Brain Stimulation With High-Frequency and Low-Intensity Repetitive Transcranial Magnetic Stimulation Treatment for Posttraumatic Stress Disorder

    PubMed Central

    Boggio, Paulo Sergio; Rocha, Martha; Oliveira, Maira Okada; Fecteau, Shirley; Cohen, Roni B.; Campanhã, Camila; Ferreira-Santos, Eduardo; Meleiro, Alexandrina; Corchs, Felipe; Zaghi, Soroush; Pascual-Leone, Alvaro; Fregni, Felipe

    2011-01-01

    Objective We aimed to investigate the efficacy of 20 Hz repetitive transcranial magnetic stimulation (rTMS) of either right or left dorsolateral prefrontal cortex (DLPFC) as compared to sham rTMS for the relief of posttraumatic stress disorder (PTSD)–associated symptoms. Method In this double-blind, placebo-controlled phase II trial conducted between October 2005 and July 2008, 30 patients with DSM-IV–diagnosed PTSD were randomly assigned to receive 1 of the following treatments: active 20 Hz rTMS of the right DLPFC, active 20 Hz rTMS of the left DLPFC, or sham rTMS. Treatments were administered in 10 daily sessions over 2 weeks. A blinded rater assessed severity of core PTSD symptoms, depression, and anxiety before, during, and after completion of the treatment protocol. In addition, a battery of neuropsychological tests was measured before and after treatment. Results Results show that both active conditions—20 Hz rTMS of left and right DLPFC—induced a significant decrease in PTSD symptoms as indexed by the PTSD Checklist and Treatment Outcome PTSD Scale; however, right rTMS induced a larger effect as compared to left rTMS. In addition, there was a significant improvement of mood after left rTMS and a significant reduction of anxiety following right rTMS. Improvements in PTSD symptoms were long lasting; effects were still significant at the 3-month follow-up. Finally, neuropsychological evaluation showed that active 20 Hz rTMS is not associated with cognitive worsening and is safe for use in patients with PTSD. Conclusions These results support the notion that modulation of prefrontal cortex can alleviate the core symptoms of PTSD and suggest that high-frequency rTMS of right DLPFC might be the optimal treatment strategy. PMID:20051219

  20. Tinnitus in Normal-Hearing Participants after Exposure to Intense Low-Frequency Sound and in Ménière's Disease Patients.

    PubMed

    Ueberfuhr, Margarete Anna; Wiegrebe, Lutz; Krause, Eike; Gürkov, Robert; Drexl, Markus

    2016-01-01

    Tinnitus is one of the three classical symptoms of Ménière's disease (MD), an inner ear disease that is often accompanied by endolymphatic hydrops. Previous studies indicate that tinnitus in MD patients is dominated by low frequencies, whereas tinnitus in non-hydropic pathologies is typically higher in frequency. Tinnitus of rather low-frequency (LF) quality was also reported to occur for about 90 s in normal-hearing participants after presentation of intense, LF sound (120 dB SPL, 30 Hz, 90 s). LF sound has been demonstrated to also cause temporary endolymphatic hydrops in animal models. Here, we quantify tinnitus in two study groups with chronic (MD patients) and presumably transient endolymphatic hydrops (normal-hearing participants after LF exposure) with a psychophysical procedure. Participants matched their tinnitus either with a pure tone of adjustable frequency and level or with a noise of adjustable spectral shape and level. Sensation levels of matching stimuli were lower for MD patients (mean: 8 dB SL) than for normal-hearing participants (mean: 15 dB SL). Transient tinnitus after LF-exposure occurred in all normal-hearing participants (N = 28). About half of the normal-hearing participants matched noise to their tinnitus, the other half chose a pure tone with frequencies below 2 kHz. MD patients matched their tinnitus with either high-frequency pure tones, mainly above 3 kHz, or with a noise. Despite a significant proportion of MD patients matching low-pass (roaring) noises to their tinnitus, the range of matched stimuli was more heterogeneous than previous data suggested. We propose that in those participants with noise-like tinnitus, the percept is probably generated by increased spontaneous activity of auditory nerve fibers with a broad range of characteristic frequencies, due to an impaired ion balance in the cochlea. For tonal tinnitus, additional mechanisms are conceivable: focal hair cell loss can result in decreased auditory

  1. Tinnitus in Normal-Hearing Participants after Exposure to Intense Low-Frequency Sound and in Ménière’s Disease Patients

    PubMed Central

    Ueberfuhr, Margarete Anna; Wiegrebe, Lutz; Krause, Eike; Gürkov, Robert; Drexl, Markus

    2017-01-01

    Tinnitus is one of the three classical symptoms of Ménière’s disease (MD), an inner ear disease that is often accompanied by endolymphatic hydrops. Previous studies indicate that tinnitus in MD patients is dominated by low frequencies, whereas tinnitus in non-hydropic pathologies is typically higher in frequency. Tinnitus of rather low-frequency (LF) quality was also reported to occur for about 90 s in normal-hearing participants after presentation of intense, LF sound (120 dB SPL, 30 Hz, 90 s). LF sound has been demonstrated to also cause temporary endolymphatic hydrops in animal models. Here, we quantify tinnitus in two study groups with chronic (MD patients) and presumably transient endolymphatic hydrops (normal-hearing participants after LF exposure) with a psychophysical procedure. Participants matched their tinnitus either with a pure tone of adjustable frequency and level or with a noise of adjustable spectral shape and level. Sensation levels of matching stimuli were lower for MD patients (mean: 8 dB SL) than for normal-hearing participants (mean: 15 dB SL). Transient tinnitus after LF-exposure occurred in all normal-hearing participants (N = 28). About half of the normal-hearing participants matched noise to their tinnitus, the other half chose a pure tone with frequencies below 2 kHz. MD patients matched their tinnitus with either high-frequency pure tones, mainly above 3 kHz, or with a noise. Despite a significant proportion of MD patients matching low-pass (roaring) noises to their tinnitus, the range of matched stimuli was more heterogeneous than previous data suggested. We propose that in those participants with noise-like tinnitus, the percept is probably generated by increased spontaneous activity of auditory nerve fibers with a broad range of characteristic frequencies, due to an impaired ion balance in the cochlea. For tonal tinnitus, additional mechanisms are conceivable: focal hair cell loss can result in decreased

  2. 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.

  3. 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.

  4. 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

  5. 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.

  6. SU-E-T-358: Empirical Beam Angle Optimization for Lung Cancer Intensity Modulated Radiation Therapy

    SciTech Connect

    Doozan, B; Pella, S

    2015-06-15

    Purpose: Creating an improved BAO can decrease the amount of time a dosimetrist spends on making a treatment plan, improve the treatment quality and enhance the tools an inexperienced dosimetrist can use to develop planning techniques. Methods: Using empirical data created by experienced dosimetrists from 69 patients treated for lung cancer, the most frequently used gantry angles were applied to four different regions in each lung to gather an optimal set of fields that could be used to treat future lung cancer patients. This method, given the moniker FAU BAO, is compared in 7 plans created with the Eclipse BAO choosing 5 fields and 9 fields. Results: The results show that the conformality index improved by 30% or 3% when using the 5 and 9 fields. The conformation number was better by 12% from the 5 fields and 9% from the 9 fields. The organs at risk (OAR) were overall more protected to produce fewer nonstochastic effects from the radiation treatment with the FAU BAO. Conclusion: Empirical methods for beam angle optimization is a viable method for IMRT treatment planning techniques.

  7. Low intensity focused ultrasound (LOFU) modulates unfolded protein response and sensitizes prostate cancer to 17AAG

    PubMed Central

    Saha, Subhrajit; Bhanja, Payel; Partanen, Ari; Zhang, Wei; Liu, Laibin; Tomé, Wolfgang; Guha, Chandan

    2014-01-01

    The hypoxic tumor microenvironment generates oxidative Endoplasmic Reticulum (ER) stress, resulting in protein misfolding and unfolded protein response (UPR). UPR induces several molecular chaperones including heat-shock protein 90 (HSP90), which corrects protein misfolding and improves survival of cancer cells and resistance to tumoricidal therapy although prolonged activation of UPR induces cell death. The HSP90 inhibitor, 17AAG, has shown promise against various solid tumors, including prostate cancer (PC). However, therapeutic doses of 17AAG elicit systemic toxicity. In this manuscript, we describe a new paradigm where the combination therapy of a non-ablative and non-invasive low energy focused ultrasound (LOFU) and a non-toxic, low dose 17AAG causes synthetic lethality and significant tumoricidal effects in mouse and human PC xenografts. LOFU induces ER stress and UPR in tumor cells without inducing cell death. Treatment with a non-toxic dose of 17AAG further increased ER stress in LOFU treated PC and switch UPR from a cytoprotective to an apoptotic response in tumors resulting significant induction of apoptosis and tumor growth retardation. These observations suggest that LOFU-induced ER stress makes the ultrasound-treated tumors more susceptible to chemotherapeutic agents, such as 17AAG. Thus, a novel therapy of LOFU-induced chemosensitization may be designed for locally advanced and recurrent tumors. PMID:25594042

  8. 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

  9. [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.

  10. Trends in malignant skin melanoma and other skin cancers in Spain, 1975-1983, and their relation to solar radiation intensity.

    PubMed

    Morales Suárez-Varela, M; Llopis-González, A; Lacasaña-Navarro, M; Ferrandiz-Ferragud, J

    1990-01-01

    Epidemiological studies have shown solar exposure to play an important role in the appearance of skin cancer. We investigated the association between mortality standardized by the indirect method for malignant skin melanoma and other skin cancers and the mean intensity of solar radiation during July and August for the different provinces in Spain. A statistically significant relation was observed (p less than .05) for these two months but not upon considering mean annual solar radiation. We thus suggest that intermittent, intense exposure to sunlight constitutes an important risk factor for skin cancer. We observed an 8.5% and 15.72% increase in mortality due to malignant skin melanoma and other skin cancers, respectively, during the period 1975-1983. Mortality was slightly higher among males than females.

  11. [The first experience with using high frequency thermo-destruction in patients with metastatic cancer of the liver].

    PubMed

    Iarema, I V; Kolobov, S V; Trandofilov, M M

    2003-01-01

    Thermodestruction of the metastatic cancer of the liver was used in 18 patients. A high frequency induction thermodestructor ELECTROTOM HITT ("Berhtold" Germany) with the working frequency 343 kHz and power 0-60 Wt was used. After the ablation of the main focus the thermodestruction of metastases was performed in the liver. The effects of thermodestruction were estimated by the intraoperative biopsy before and after thermodestruction. The procedure was considered effective if biopsy revealed necrobiotic tissues. A connective tissue scar was formed at the place of thermodestruction. After operation the patients were given polychemotherapy.

  12. Postoperative Intensity-Modulated Radiotherapy in Low-Risk Endometrial Cancers: Final Results of a Phase I Study

    SciTech Connect

    Macchia, Gabriella; Cilla, Savino M.P.; Ferrandina, Gabriella; Padula, Gilbert D.A.; Deodato, Francesco; Digesu, Cinzia; Caravatta, Luciana; Picardi, Vincenzo; Corrado, Giacomo; Piermattei, Angelo; Valentini, Vincenzo; Cellini, Numa; Scambia, Giovanni; Morganti, Alessio Giuseppe

    2010-04-15

    Purpose: To determine the maximum tolerated dose of short-course radiotherapy (intensity-modulated radiotherapy technique) to the upper two thirds of the vagina in endometrial cancers with low risk of local recurrence. Patients and Methods: A Phase I clinical trial was performed. Eligible patients had low-risk resected primary endometrial adenocarcinomas. Radiotherapy was delivered in 5 fractions over 1 week. The planning target volume was the clinical target volume plus 5 mm. The clinical target volume was defined as the upper two thirds of the vagina as evidenced at CT simulation by a vaginal radio-opaque device. The planning target volume was irradiated by a seven-field intensity-modulated radiotherapy technique, planned by the Plato Sunrise inverse planning system. A first cohort of 6 patients received 25 Gy (5-Gy fractions), and a subsequent cohort received 30 Gy (6-Gy fractions). The Common Toxicity Criteria scale, version 3.0, was used to score toxicity. Results: Twelve patients with endometrial cancer were enrolled. Median age was 58 years (range, 49-74 years). Pathologic stage was IB (83.3%) and IC (16.7%). Median tumor size was 30 mm (range, 15-50 mm). All patients completed the prescribed radiotherapy. No patient experienced a dose-limiting toxicity at the first level, and the radiotherapy dose was escalated from 25 to 30 Gy. No patients at the second dose level experienced dose-limiting toxicity. The most common Grade 2 toxicity was gastrointestinal, which was tolerable and manageable. Conclusions: The maximum tolerated dose of short-course radiotherapy was 30 Gy at 6 Gy per fraction. On the basis of this result, we are conducting a Phase II study with radiotherapy delivered at 30 Gy.

  13. 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.

  14. Enhancement of cancer chemotherapy in vitro by intense ultrawideband electric field pulses

    NASA Astrophysics Data System (ADS)

    Jordan, David W.; Uhler, Michael D.; Gilgenbach, Ronald M.; Lau, Y. Y.

    2006-05-01

    Experiments have been performed to enhance the Jurkat cell-killing effects of the cancer chemotherapy agent bleomycin using electric field pulses of 50-200 kV/cm peak electric field strength, ~150 ns duration, and nanosecond rise time. Dramatic increases in cell killing (factors of ~1000) were observed with a low dose of bleomycin after treatment with trains of ten or more pulses at all electric field strengths tested, compared to pulse-only or drug-only treatments. Cell death occurred within 24 h for treated cells, with some evidence of membrane phosphatidylserine externalization at 6 h postexposure but no significant increase in caspase activity, indicating that the primary mode of cell death was not caspase-mediated apoptosis.

  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. 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

  18. 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

  19. Review of allogeneic hematopoietic stem cell transplantation with reduced intensity conditioning in solid tumors excluding breast cancer

    PubMed Central

    Karadurmus, Nuri; Sahin, Ugur; Basgoz, Bilgin Bahadir; Arpaci, Fikret; Demirer, Taner

    2016-01-01

    Solid tumors in adults constitute a heterogeneous group of malignancy originating from various organ systems. Solid tumors are not completely curable by chemotherapy, even though some subgroups are very chemo-sensitive. Recently, oncologists have focused on the use of allogeneic hematopoietic stem cell transplantation (allo-HSCT) with reduced intensity conditioning (RIC) for the treatment of some refractory solid tumors. After the demonstration of allogeneic graft-versus-leukemia effect in patients with hematological malignancies who received allo-HSCT, investigators evaluated this effect in patients with refractory metastatic solid tumors. According to data from experimental animal models and preliminary clinical trials, a graft-versus-tumor (GvT) effect may also be observed in the treatment of some solid tumors (e.g., renal cell cancer, colorectal cancer, etc.) after allo-HSCT with RIC. The use of RIC regimens offers an opportunity of achieving full-donor engraftment with GvT effect, as well as, a reduced transplant-related mortality. Current literature suggests that allo-HSCT with RIC might become a choice for elderly and medically fragile patients with refractory metastatic solid tumors. PMID:28058217

  20. Comparison between high-intensity focused ultrasound devices for the treatment of patients with localized prostate cancer

    NASA Astrophysics Data System (ADS)

    Kim, Hakushi; Tomonaga, Tetsuro; Shoji, Sunao; Uchida, Toyoaki

    2017-03-01

    To evaluate the association between long-term clinical outcomes and morbidity of patients with prostate cancer who underwent high-intensity focused ultrasound (HIFU). We included 918 patients with stage T1c-T3N0M0 prostate cancer who were treated with Sonablate™ (SB) devices during 1999-2012 and followed-up for >2 years. Risk stratification and complication rates were compared between the treatment groups. The 10-year overall and cancer-specific survival rates were 89.6% and 97.4%, respectively. The 5-year biochemical disease-free survival (bDFS) rates in the SB200/500, SB500 version 4, and SB500 tissue change monitor groups were 48.3%, 62.3%, and 82.0%, respectively (p < 0.0001). In the low-, intermediate-, and high-risk categories, the 10-year bDFS rates for all patients were 63%, 52%, and 32%, respectively (p < 0.0001), whereas the 5-year bDFS rates in the tissue change monitor group were 95%, 84%, and 72%, respectively (p = 0.0134). The overall negative biopsy rate was 87.3%. Multivariate analysis showed pre-treatment serum prostate-specific antigen levels, neoadjuvant hormonal therapy, and devices as significant predictors (p < 0.0001). Urethral stricture, epididymitis, and urinary incontinence were observed in 19.7%, 6.2%, and 2.3% of the cases, respectively. Long-term follow-up with HIFU demonstrated improved clinical outcomes owing to technical, imaging, and technological advancements.

  1. 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.

  2. 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.

  3. [High-intensity focused ultrasound (HIFU): our experience in the treatment of prostate cancer relapsing after radiotherapy].

    PubMed

    Giovanessi, Luca; Peroni, Angelo; Mirabella, Giuseppe; Fugini, Andrea Vismara; Zani, Danilo; Cunico, Sergio Cosciani; Simeone, Claudio

    2011-01-01

    The aim of the study is to evaluate the safety and efficacy of high-intensity focused ultrasound (HIFU) treatment in patients with local prostate cancer recurrence after radiotherapy. From February 2009 to June 2010, 14 patients with prostate cancer recurrence after radiotherapy were selected for HIFU treatment; all patients had a positive TRUS-guided biopsy and the absence of distant metastases was confirmed by computer tomography, PET choline or bone scintigraphy. We classified all patients in 3 groups using D'Amico's classification: 4 patients high risk (PSA >20 ng/ml - 8≤ Gleason Score≤ 10 - clinical stage≥T2c), 8 patients intermediate risk (10 PSAnadir+1.2ng/ml) or after adjuvant therapy introduction. All complications were recorded. Of the 14 patients selected, 12 patients underwent HIFU treatments; 2 patients were excluded because of rectal strictures induced by radiotherapy. At a mean 13 months' follow-up, biochemical success rate was obtained in 1 of the high risk patients and in 5 of the low and intermediate risk patients; 1 man died for a disease not correlated with prostate cancer recurrence. Complications included urinary tract infection, acute urinary retentions, urethral strictures and light stress incontinence. In our experience salvage HIFU is a safe treatment option for local relapse after radiotherapy; its efficacy depends on a careful patient selection.

  4. Use of a correlation analysis model in the optimization of intensity-modulated radiotherapy of prostate cancer.

    PubMed

    Li, Xiadong; Deng, Qinghua; Ma, Shenglin; Zhang, K E; Wu, Zhibing; Lai, Jianjun; Tang, Rongjun; Ren, Yao; Wang, Jiahao; Xu, Lixia

    2015-12-01

    The aim of the present study was to develop a statistical model-based method for the optimization of intensity-modulated radiotherapy (IMRT). A prostate cancer IMRT plan was redesigned while retaining the same beam orientation and prescribed dose as the regular plan. A series of dosimetric parameters were generated, and a 4-step protocol was performed to analyze the data: i) The tumor control probability of the target was ensured by setting a number of strict constraint parameters so that much of the target was covered by the 95% isodose line; ii) the parameters for optimization [weight ratio, equivalent characteristic parameter a and maximum equivalent uniform dose of the organ at risk (OAR)] were adjusted; iii) the overall optimization space (OOS) was determined via analysis of the dose-parameter tables based on the correlation factor (CF) and optimization efficiency factor analysis; iv) the OOS in the Pinnacle V7.6 treatment planning system with IMRT function was transposed. A selected optimization phenomenon existed when different optimization methods were used to optimize dose distribution to the targets and OARs, which demonstrates a wide variation in the CFs between the percentage of planning target volume receiving 95% of the prescribed dose and the maximum dose of the bladder, rectum and femur. The OOS used to optimize the randomly selected plan exhibited relatively high efficiency, with benefits for the optimization of IMRT plans. For patients with prostate cancer who require complex IMRT plan optimization, the obtained OOS from the two core analysis techniques is likely to have relatively high efficiency in achieving an optimized plan. These results suggest that the correlation analysis model is a novel method for the optimization of IMRT for prostate cancer.

  5. 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.

  6. 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

  7. Long-Term Breast Cancer Patient Outcomes After Adjuvant Radiotherapy Using Intensity-Modulated Radiotherapy or Conventional Tangential Radiotherapy.

    PubMed

    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

    2016-03-01

    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.

  8. Beam Path Toxicities to Non-Target Structures During Intensity-Modulated Radiation Therapy for Head and Neck Cancer

    SciTech Connect

    Rosenthal, David I. Chambers, Mark S.; Fuller, Clifton D.; Kies, Merrill S.

    2008-11-01

    Background: Intensity-modulated radiation therapy (IMRT) beams traverse nontarget normal structures not irradiated during three-dimensional conformal RT (3D-CRT) for head and neck cancer (HNC). This study estimates the doses and toxicities to nontarget structures during IMRT. Materials and Methods: Oropharyngeal cancer IMRT and 3D-CRT cases were reviewed. Dose-volume histograms (DVH) were used to evaluate radiation dose to the lip, cochlea, brainstem, occipital scalp, and segments of the mandible. Toxicity rates were compared for 3D-CRT, IMRT alone, or IMRT with concurrent cisplatin. Descriptive statistics and exploratory recursive partitioning analysis were used to estimate dose 'breakpoints' associated with observed toxicities. Results: A total of 160 patients were evaluated for toxicity; 60 had detailed DVH evaluation and 15 had 3D-CRT plan comparison. Comparing IMRT with 3D-CRT, there was significant (p {<=} 0.002) nonparametric differential dose to all clinically significant structures of interest. Thirty percent of IMRT patients had headaches and 40% had occipital scalp alopecia. A total of 76% and 38% of patients treated with IMRT alone had nausea and vomiting, compared with 99% and 68%, respectively, of those with concurrent cisplatin. IMRT had a markedly distinct toxicity profile than 3D-CRT. In recursive partitioning analysis, National Cancer Institute's Common Toxicity Criteria adverse effects 3.0 nausea and vomiting, scalp alopecia and anterior mucositis were associated with reconstructed mean brainstem dose >36 Gy, occipital scalp dose >30 Gy, and anterior mandible dose >34 Gy, respectively. Conclusions: Dose reduction to specified structures during IMRT implies an increased beam path dose to alternate nontarget structures that may result in clinical toxicities that were uncommon with previous, less conformal approaches. These findings have implications for IMRT treatment planning and research, toxicity assessment, and multidisciplinary patient

  9. SU-E-T-617: Plan Quality Estimation of Intensity-Modulated Radiotherapy Cases for Lung Cancer

    SciTech Connect

    Koo, J; Yoon, M; Chung, W; Kim, D

    2015-06-15

    Purpose: To estimate the planning quality of intensity-modulated radiotherapy in lung cancer cases and to provide preliminary data for the development of a planning quality assurance algorithm. Methods: 42 IMRT plans previously used in cases of solitary lung cancers were collected. Organs in or near the thoracic cavity, such as lung (ipsilateral, contralateral), heart, liver, esophagus, cord and bronchus were considered as organs at risk (OARs) in this study. The coverage index (CVI), conformity index (CI), homogeneity index (HI), volume, irregularity (standard deviation of center-surface distance) were used to compare PTV dose characteristics. The effective uniform dose (EUD), V10Gy, and V20Gy of the OARs were used to compare OAR dose characteristics. Results: Average CVI, CI, HI values were 0.9, 0.8, 0.1, respectively. CVI and CI had narrow Gaussian distribution curves without a singular value, but one case had a relatively high (0.25) HI because of location and irregular shape (Irregularity of 18.5 when average was 12.5) of PTV. EUDs tended to decrease as OAR-PTV distance increased and OAR-PTV overlap volume decreased. Conclusion: This work indicates the potential for significant plan quality deviation of similar lung cancer cases. Considering that this study were from a single department, differences in the treatment results for a given patient would be much more pronounced if multiple departments (and therefore more planners) were involved. Therefore, further examination of QA protocols is needed to reduce deviations in radiation treatment planning.

  10. [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.

  11. Invoking the frequency dependence in square modulated light intensity techniques for the measurement of electron time constants in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Ghaithan, Hamid M.; Qaid, Saif M.; Hezam, Mahmoud; Siddique, Muhemmad B.; Bedja, Idriss M.; Aldwayyana, Abdullah S.

    2015-08-01

    Dye-sensitized solar cells (DSSCs) have been considered as one of the most promising new generation solar cells. Enormous research efforts have been invested to improve the efficiency of solar energy conversion which is determined by the light harvesting efficiency, electron injection efficiency and undesirable electron lifetime. A simple, cheap and trustable laser-induced photovoltage and photocurrent decay (LIPVCD) technique is adopted in this work in order to determine the electron lifetime (τe) and electron transport (τtr) in DSSCs. In LIPVCD technique, DSSC is illuminated by a small squared intensity-modulated laser beam. Time-based response of the DSSC is recorded using a transient digitized oscilloscope for further analysis. Frequency-based response was also investigated in this work. The frequency-dependent measurements turned out to be a powerful method to determine electron time constants in a fast, real-time fashion. Measurements were carried out using a standard dye-sensitized solar cell, and results were in excellent agreement with results obtained from traditional IMVS-MPS measurements. Measurements were also performed for a variety of DSSCs, having various electrodes including TiO2 nanoparticles, TiO2 nanosheets with exposed {001} facets and ZnO vertically aligned nanowires. Results will also be presented and discussed in this work.

  12. 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.

  13. 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.

  14. A frequency-based approach to locate common structure for 2D-3D intensity-based registration of setup images in prostate radiotherapy

    SciTech Connect

    Munbodh, Reshma; Chen Zhe; Jaffray, David A.; Moseley, Douglas J.; Knisely, Jonathan P. S.; Duncan, James S.

    2007-07-15

    In many radiotherapy clinics, geometric uncertainties in the delivery of 3D conformal radiation therapy and intensity modulated radiation therapy of the prostate are reduced by aligning the patient's bony anatomy in the planning 3D CT to corresponding bony anatomy in 2D portal images acquired before every treatment fraction. In this paper, we seek to determine if there is a frequency band within the portal images and the digitally reconstructed radiographs (DRRs) of the planning CT in which bony anatomy predominates over non-bony anatomy such that portal images and DRRs can be suitably filtered to achieve high registration accuracy in an automated 2D-3D single portal intensity-based registration framework. Two similarity measures, mutual information and the Pearson correlation coefficient were tested on carefully collected gold-standard data consisting of a kilovoltage cone-beam CT (CBCT) and megavoltage portal images in the anterior-posterior (AP) view of an anthropomorphic phantom acquired under clinical conditions at known poses, and on patient data. It was found that filtering the portal images and DRRs during the registration considerably improved registration performance. Without filtering, the registration did not always converge while with filtering it always converged to an accurate solution. For the pose-determination experiments conducted on the anthropomorphic phantom with the correlation coefficient, the mean (and standard deviation) of the absolute errors in recovering each of the six transformation parameters were {theta}{sub x}:0.18(0.19) deg., {theta}{sub y}:0.04(0.04) deg., {theta}{sub z}:0.04(0.02) deg., t{sub x}:0.14(0.15) mm, t{sub y}:0.09(0.05) mm, and t{sub z}:0.49(0.40) mm. The mutual information-based registration with filtered images also resulted in similarly small errors. For the patient data, visual inspection of the superimposed registered images showed that they were correctly aligned in all instances. The results presented in this

  15. 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

  16. 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,