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Sample records for craniospinal axis irradiation

  1. Craniospinal axis irradiation: an improved electron technique for irradiation of the spinal axis

    International Nuclear Information System (INIS)

    Chun Li; Vijayakumar, S.; Myrianthopoulos, L.C.; Kuchnir, F.T.; Muller-Runkel, R.

    1994-01-01

    The authors review dosimetric features of craniospinal axis irradiation in the areas of matching cranial and spinal fields, with reference to normal structures within the spinal field. The implications of the use of photon or electron modalities for the spinal port were evaluated. A novel method of matching the cranial photon and the spinal electron fields involving a computer-aided junction design is presented, involving moving the photon beam in three steps to degrade its penumbra to match that of the electron field. Thermoluminescent dosimetry in a Rando phantom and computed tomography-based dose-volume histogram study for an illustrative paediatric case were used to compare dose to normal structures within the spinal field. Results show that the use of electrons for the spinal field leads to better sparing of deep seated normal structures. For bone marrow, the use of a customized bolus for the spinal field results in an improved dose distribution, making electrons potentially superior to photons for radiobiological reasons. (author)

  2. Kinetic modeling of tumor growth and dissemination in the craniospinal axis: implications for craniospinal irradiation

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    Halperin Edward C

    2006-12-01

    Full Text Available Abstract Background Medulloblastoma and other types of tumors that gain access to the cerebrospinal fluid can spread throughout the craniospinal axis. The purpose of this study was to devise a simple multi-compartment kinetic model using established tumor cell growth and treatment sensitivity parameters to model the complications of this spread as well as the impact of treatment with craniospinal radiotherapy. Methods A two-compartment mathematical model was constructed. Rate constants were derived from previously published work and the model used to predict outcomes for various clinical scenarios. Results The model is simple and with the use of known and estimated clinical parameters is consistent with known clinical outcomes. Treatment outcomes are critically dependent upon the duration of the treatment break and the radiosensitivity of the tumor. Cross-plot analyses serve as an estimate of likelihood of cure as a function of these and other factors. Conclusion The model accurately describes known clinical outcomes for patients with medulloblastoma. It can help guide treatment decisions for radiation oncologists treating patients with this disease. Incorporation of other treatment modalities, such as chemotherapy, that enhance radiation sensitivity and/or reduce tumor burden, are predicted to significantly increase the probability of cure.

  3. Craniospinal axis irradiation in children. Treatment in supine position including field verification as a prerequisite for anesthesia without intubation

    International Nuclear Information System (INIS)

    Rades, D.; Holtzhauer, R.; Baumann, R.; Karstens, J.H.; Leuwer, M.

    1999-01-01

    Purpose: For craniospinal axis irradiation in young children sometimes anesthesia is required. In order to minimize risks from the anesthesist's point of view supine position would be preferable to standard prone position. In case of irradiation in supine position verification of the 3-field junction in the cervical region causes problems, because there is no direct visual control. For such situations the clinical application of a new technique is presented. Patients and Methods: For treatment planning a modern 3D planning system was necessary. Patient's positioning was done by using a vacuum-form body immobilizer and an integrated head mask. Radiation fields were placed only by table movements being calculated by the planning system in relation to a reference point at the patient's surface. In addition to common verification films specially prepared small films were used for the 3-field junction in the cervical region. These films were placed close to the patient for the whole time of each radiation session being exposed by every radiation field. Results: Two children (age 3 and 5 years, respectively) were irradiated as described. Twenty-eight of those specially prepared films were exposed. Two films (7%) had to be excluded because of inadequate exposure. An overlap of radiation fields was seen on 1 of the 26 remaining films (4%), whereas an unacceptable gap was not found. Acute skin reactions were comparable to those observed in patients being irradiated in standard prone position. Conclusion: The presented technique for craniospinal axis irradiation in supine position including field verification was not only precise and reproducible, but also comfortable and safe for the patient. We suggest it as a new option for craniospinal axis irradiation in children. (orig.) [de

  4. Craniospinal Irradiation for Trilateral Retinoblastoma Following Ocular Irradiation

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    Marks, Lawrence B.; Bentel, Gunilla; Sherouse, George W.; Spencer, David P.; Light, Kim

    2015-01-15

    A case study is presented. Craniospinal radiotherapy and a three-field pineal boost for trilateral retinoblastoma were delivered to a patient previously irradiated for ocular retinoblastoma. The availability of CT-based three-dimensional treatment planning provided the capability of identifying the previously irradiated volume as a three-dimensional anatomic structure and of designing a highly customized set of treatment beams that minimized reirradiation of that volume.

  5. The technique of craniospinal irradiation of paediatric patients in supine position

    International Nuclear Information System (INIS)

    Slampa, P.; Seneklova, Z.; Simicek, J.; Soumarova, R.; Burkon, P.; Burianova, L.

    2001-01-01

    Background. Postoperative radiation therapy has significant impact on local control and overall survival of paediatric patients with brain tumours but an irradiated volume is often a controversial issue. Our aim was to describe a new technique of craniospinal irradiation as a postoperative treatment in patients with the risk of relapse of brain tumours as well as to estimate the side effects of such craniospinal irradiation. Patients and methods. In the last 4 years, 17 paediatric patients under 15 years of age with medulloblastoma (8) ependymoma (6) and glioblastoma (3) received postoperative craniospinal axis radiotherapy by a new technique developed in our departments. This technique is based on irradiation in supine position with the use of asymmetric jaws of the linear accelerator. Results. Radiotherapy was well tolerated and dose-reduction was not needed in any case. Skin reactions were mild in all patients. The gastrointestinal and haematological toxicity was mild to moderate (WHO grade I-II). Conclusion. The proposed new technique of craniospinal irradiation is advantageous in terms of side effects and could be recommended to be widely used. Craniospinal irradiation in supine position is an alternative method to the treatment in prone position. The evaluation of the effectiveness was limited by a short follow-up interval. (author)

  6. HIT`91 (prospective, co-operative study for the treatment of malignant brain tumors in childhood): accuracy and acute toxicity of the irradiation of the craniospinal axis

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    Kortmann, R.D.; Timmermann, B.; Bamberg, M. [Tuebingen Univ. (Germany). Dept. of Radiotherapy; Kuehl, J. [Wuerzburg Univ. (Germany). Children`s Hospital; Willich, N. [Muenster Univ. (Germany). Dept. of Radiotherapy; Flentje, M. [Wuerzburg Univ. (Germany). Dept. of Radiotherapy; Meisner, C. [Tuebingen Univ. (Germany). Inst. for Medical Information Processing

    1999-04-01

    Background: It was the aim of the quality control program of the randomized trial HIT `91 (intensive chemotherapy before irradiation versus maintenance chemotherapy after irradiation) to assess prospectively the quality of neuroaxis irradiation with respect to the protocol guidelines and to evaluate acute toxicity with respect to treatment arm. Patients, Materials and Methods: Data of 134 patients undergoing irradiation of the craniospinal axis were available. Positioning aids, shielding techniques, treatment machines, choice of energy, total dose and fractionation were evaluated. A total of 651 simulation and verification films were analyzed to assess the coverage of the clinical target volume (whole brain, posterior fossa, sacral nerve roots) and deviations of field alignment between simulation and verification of first treatment. Field matching between whole brain and adjacent cranial spinal fields was analyzed with respect to site and width of junction. Acute maximal side effects were evaluated according to a modified WHO score for neurotoxicity, infections, skin, mucosa and myelotoxicity. Results: In 91.3% of patients contemporary positioning aids and individualized shielding techniques were used to assure a reproducible treatment. In 98 patients (73.1%) linear accelerators and in 36 patients (26.8%) {sup 60}Cobalt machines were used. Single and total dose were administered according to the protocol guidelines in more than 90% of patients. In 20.2% of patients the cribriform plate, in 1.4% the middle cranial fossa and in 21.1% the posterior fossa and in 4.5% the 2nd sacral segment were incompletely encompassed by the treatment portals. Ninety-five percent of deviations of field alignment were less than 13.0 mm (whole brain) and 12 mm (cranial spinal field) with a random error between 4.9 and 7.6 mm (whole brain) and 6.9 mm and 9.9 mm (spinal canal), respectively. In 77.5% of patients the junctions between whole brain and cranial spinal fields were placed

  7. Lymphopenia caused by cranial irradiation in children receiving craniospinal radiotherapy

    International Nuclear Information System (INIS)

    Harisiadis, L.; Kopelson, G.; Chang, C.H.

    1977-01-01

    The peripheral blood changes were studied in 67 children who received craniospinal irradiation for posterior fossa tumors. At the completion of a cranial dose of about 3500 rad to the whole brain port, the lymphocytes were reduced to 858/mm 3 from 3084/mm 3 preoperatively. The counts of the remaining leukocytes stayed at a level somewhat higher than preoperatively; the eosinophils rose to 288/mm 3 from 125/mm 3 . With the initiation of the spinal field irradiation, which included a large proportion of the total bone marrow, the numbers of all the leukocytes decreased rapidly; the observed leukopenia was mainly secondary to neutropenia. A mechanism that was operating to restore the number of leukocytes became manifest immediately after the completion of radiotherapy, though the number of lymphocytes had not been totally restored to the preoperative level 6 years later. Irradiation of the lymphocytes that circulate through the vascular bed can explain the lymphopenia observed during cranial radiotherapy. Mild leukopenia observed in patients receiving radiotherapy through a relatively small port may be secondary to lymphopenia, and this does not necessarily indicate impaired bone marrow reserves

  8. Craniospinal Irradiation With Spinal IMRT to Improve Target Homogeneity

    International Nuclear Information System (INIS)

    Panandiker, Atmaram Pai; Ning, Holly; Likhacheva, Anna; Ullman, Karen; Arora, Barbara; Ondos, John C.; Karimpour, Shervin; Packer, Roger; Miller, Robert; Citrin, Deborah

    2007-01-01

    Purpose: To report a new technique for the spinal component of craniospinal irradiation (CSI) in the supine position, to describe a verification procedure for this method, and to compare this technique with conventional plans. Methods and Materials: Twelve patients were treated between 1998 and 2006 with CSI using a novel technique. Sixteen children were treated with a conventional field arrangement. All patients were followed for outcomes and toxicity. CSI was delivered using a posteroanterior (PA) intensity-modulated radiation therapy (IMRT) spinal field matched to conventional, opposed lateral cranial fields. Treatment plans were generated for each patient using the IMRT technique and a standard PA field technique. The resulting dosimetry was compared to determine target homogeneity, maximum dose to normal tissues, and total monitor units delivered. Results: Evaluation of the spinal IMRT technique compared with a standard PA technique reveals a 7% reduction in the target volume receiving ≥110% of the prescribed dose and an 8% increase in the target volume receiving ≥95% of the prescribed dose. Although target homogeneity was improved, the maximum dose delivered in the paraspinal muscles was increased by approximately 8.5% with spinal IMRT compared to the PA technique. Follow-up evaluations revealed no unexpected toxicity associated with the IMRT technique. Conclusions: A new technique of spine IMRT is presented in combination with a quality assurance method. This method improves target dose uniformity compared to the conventional CSI technique. Longer follow-up will be required to determine any benefit with regard to toxicity and disease control

  9. CT simulation technique for craniospinal irradiation in supine position

    International Nuclear Information System (INIS)

    Lee, Suk; Kim, Yong Bae; Chu, Sung Sil; Suh, Chang Ok; Kwon, Soo Il

    2002-01-01

    In order to perform craniospinal irradiation (CSI) in the supine position on patients who are unable to lie in the prone position, a new simulation technique using a CT simulator was developed and its availability was evaluated. A CT simulator and a 3-D conformal treatment planning system were used to develop CSI in the supine position. The head and neck were immobilized with a thermoplastic mask in the supine position and the entire body was immobilized with a Vac-Loc. A volumetric image was then obtained using the CT simulator. In order to improve the reproducibility of the patients' setup, datum lines and points were marked on the head and the body. Virtual fluoroscopy was performed with the removal of visual obstacles such as the treatment table or the immobilization devices. After the virtual simulation, the treatment isocenters of each field were marked on the body and the immobilization devices at the conventional simulation room. Each treatment field was confirmed by comparing the fluoroscopy images with the digitally reconstructed radiography (DRR)/digitally composite radiography (DCR) images from the virtual simulation. The port verification films from the first treatment were also compared with the DRR/DCR images for a geometrical verification. CSI in the supine position was successfully performed in 9 patients. It required less than 20 minutes to construct the immobilization device and to obtain the whole body volumetric images. This made it possible to not only reduce the patients' inconvenience, but also to eliminate the position change variables during the long conventional simulation process. In addition, by obtaining the CT volumetric image, critical organs, such as the eyeballs and spinal cord, were better defined, and the accuracy of the port designs and shielding was improved. The difference between the DRRs and the portal films were less than 3 mm in the vertebral contour. CSI in the supine position is feasible in patients who cannot lie on

  10. CT simulation technique for craniospinal irradiation in supine position

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    Lee, Suk; Kim, Yong Bae; Chu, Sung Sil; Suh, Chang Ok [Yonsei Cancer Center, College of Medicine, Yonsei University, Seoul (Korea, Republic of); Kwon, Soo Il [Kyonggi University, Seoul (Korea, Republic of)

    2002-06-15

    In order to perform craniospinal irradiation (CSI) in the supine position on patients who are unable to lie in the prone position, a new simulation technique using a CT simulator was developed and its availability was evaluated. A CT simulator and a 3-D conformal treatment planning system were used to develop CSI in the supine position. The head and neck were immobilized with a thermoplastic mask in the supine position and the entire body was immobilized with a Vac-Loc. A volumetric image was then obtained using the CT simulator. In order to improve the reproducibility of the patients' setup, datum lines and points were marked on the head and the body. Virtual fluoroscopy was performed with the removal of visual obstacles such as the treatment table or the immobilization devices. After the virtual simulation, the treatment isocenters of each field were marked on the body and the immobilization devices at the conventional simulation room. Each treatment field was confirmed by comparing the fluoroscopy images with the digitally reconstructed radiography (DRR)/digitally composite radiography (DCR) images from the virtual simulation. The port verification films from the first treatment were also compared with the DRR/DCR images for a geometrical verification. CSI in the supine position was successfully performed in 9 patients. It required less than 20 minutes to construct the immobilization device and to obtain the whole body volumetric images. This made it possible to not only reduce the patients' inconvenience, but also to eliminate the position change variables during the long conventional simulation process. In addition, by obtaining the CT volumetric image, critical organs, such as the eyeballs and spinal cord, were better defined, and the accuracy of the port designs and shielding was improved. The difference between the DRRs and the portal films were less than 3 mm in the vertebral contour. CSI in the supine position is feasible in patients who cannot

  11. Effects of vertebral-body-sparing proton craniospinal irradiation on the spine of young pediatric patients with medulloblastoma.

    Science.gov (United States)

    MacEwan, Iain; Chou, Brian; Moretz, Jeremy; Loredo, Lilia; Bush, David; Slater, Jerry D

    2017-01-01

    To investigate the long-term effects of vertebral-body-sparing proton craniospinal irradiation (CSI) on the spine of young patients with medulloblastoma. Six children between the ages of 3 and 5 years with medulloblastoma were treated with vertebral-body-sparing proton CSI after maximal safe resection. Radiation therapy was delivered in the supine position with posterior beams targeting the craniospinal axis, and the proton beam was stopped anterior to the thecal sac. Patients were treated with a dose of either 23.4 Gy or 36 Gy to the craniospinal axis followed by a boost to the posterior fossa and any metastatic lesions. Chemotherapy varied by protocol. Radiographic effects on the spine were evaluated with serial imaging, either with magnetic resonance imaging scans or plain film using Cobb angle calculations, the presence of thoracic lordosis, lumbar vertebral body-to-disc height ratios, and anterior-posterior height ratios. Clinical outcomes were evaluated by patient/family interview and medical chart review. Overall survival and disease free survival were 83% (5/6) at follow-up. Median clinical and radiographic follow-up were 13.6 years and 12.3 years, respectively. Two patients were clinically diagnosed with scoliosis and treated conservatively. At the time of follow-up, no patients had experienced chronic back pain or required spine surgery. No patients were identified to have thoracic lordosis. Diminished growth of the posterior portions of vertebral bodies was identified in all patients, with an average posterior to anterior ratio of 0.88, which was accompanied by compensatory hypertrophy of the posterior intervertebral discs. Vertebral-body-sparing CSI with proton beam did not appear to cause increased severe spinal abnormalities in patients treated at our institution. This approach could be considered in future clinical trials in an effort to reduce toxicity and the risk of secondary malignancy and to improve adult height.

  12. Technique for sparing previously irradiated critical normal structures in salvage proton craniospinal irradiation

    International Nuclear Information System (INIS)

    McDonald, Mark W; Wolanski, Mark R; Simmons, Joseph W; Buchsbaum, Jeffrey C

    2013-01-01

    Cranial reirradiation is clinically appropriate in some cases but cumulative radiation dose to critical normal structures remains a practical concern. The authors developed a simple technique in 3D conformal proton craniospinal irradiation (CSI) to block organs at risk (OAR) while minimizing underdosing of adjacent target brain tissue. Two clinical cases illustrate the use of proton therapy to provide salvage CSI when a previously irradiated OAR required sparing from additional radiation dose. The prior radiation plan was coregistered to the treatment planning CT to create a planning organ at risk volume (PRV) around the OAR. Right and left lateral cranial whole brain proton apertures were created with a small block over the PRV. Then right and left lateral “inverse apertures” were generated, creating an aperture opening in the shape of the area previously blocked and blocking the area previously open. The inverse aperture opening was made one millimeter smaller than the original block to minimize the risk of dose overlap. The inverse apertures were used to irradiate the target volume lateral to the PRV, selecting a proton beam range to abut the 50% isodose line against either lateral edge of the PRV. Together, the 4 cranial proton fields created a region of complete dose avoidance around the OAR. Comparative photon treatment plans were generated with opposed lateral X-ray fields with custom blocks and coplanar intensity modulated radiation therapy optimized to avoid the PRV. Cumulative dose volume histograms were evaluated. Treatment plans were developed and successfully implemented to provide sparing of previously irradiated critical normal structures while treating target brain lateral to these structures. The absence of dose overlapping during irradiation through the inverse apertures was confirmed by film. Compared to the lateral X-ray and IMRT treatment plans, the proton CSI technique improved coverage of target brain tissue while providing the least

  13. Survival of very young children with medulloblastoma (primitive neuroectodermal tumor of the posterior fossa) treated with craniospinal irradiation

    International Nuclear Information System (INIS)

    Saran, Frank H.; Driever, Pablo Herniz; Thilmann, Christoph; Mose, Stephan; Wilson, Paula; Sharpe, Geoff; Adamietz, Irenaeus A.; Boettcher, Heinz D.

    1998-01-01

    Purpose: Very young children with medulloblastoma are considered to have a worse prognosis than older children. As radiotherapy remains an important part of the treatment, the adverse prognosis could be due to inadequate radiation treatment rather than biological factors. We analyzed the published literature to examine the impact of radiotherapy on survival in this group. Methods and Materials: A Medline search was performed and we reviewed studies of treatment of medulloblastoma where radiotherapy was delivered using megavoltage equipment and the minimum follow-up allowed the calculation of 5-year survival rates. Results: Thirty-nine studies were published between 1979 and 1996 with a treatment including craniospinal irradiation and boost to the posterior fossa. Eleven studies comprising 1366 patients analyzed survival by age at diagnosis. Eight of 11 studies showed a worse 5-year survival for the younger patient group which reached statistical significance in two. There is also a suggestion of a higher proportion of children with metastatic disease at presentation in the very young age group. The usual policy in younger children was to give a lower dose of radiotherapy to the craniospinal axis (CSA) and posterior fossa (PF) with reduction of dose in the range of 15 to 25% compared to standard treatment. As dose reduction to the posterior fossa is associated with worse survival and local recurrence is the predominant site of failure, the major determinant of worse survival in very young children with medulloblastoma may be suboptimal radiotherapy. Protocols including postoperative chemotherapy with delayed, omitted, or only local tumor irradiation do not reach survival rates of protocols with standard radiotherapy, also suggesting a continued importance for irradiation. Conclusion: Very young children with medulloblastoma have a worse prognosis than older children. Inadequate radiation dose and technique to the primary tumor region may be a major contributing

  14. A mono isocentric radiotherapy technique for craniospinal irradiation using asymmetric jaws

    International Nuclear Information System (INIS)

    Isin, G; Oezyar, E.; Guerdalli, S.; Arslan, G.; Uzal, D.; Atahan, I. L.

    1995-01-01

    Dose distribution across the junction of matching of craniospinal fields (lateral cranial fields and posterior spinal field) is important as severe complications may result if the beams overlap or disease may recurs if the gapping is too conservative. Various techniques have been used to achieve an effective transverse plane match and half-beam block technique is one of these techniques. Here, we describe a mono isocentric technique for the treatment of craniospinal fields using the asymmetric jaws of our linear accelerator (Philips SL-25). Before the clinical application of this non-standard technique, basic dosimetry parameters are evaluated. Asymmetric collimator dose distributions for various asymmetric field sizes were obtained and compared with symmetric dose distributions for 6 MV x-ray. A computerized 3-D water phantom with a pair of ionization chambers (reference and field) was used for dose profiles, isodose distributions and Percentage Depth Dose (PDD) for various asymmetric field sizes and different off axis distances. The measured values of off axis ratios for the interested depths were used in MU calculations. This new mono isocentric technique provides an ideal dose distribution at match-line as there is no need to move the patient during treatment. Use of heavy secondary cerrobend blocks (beam splitters) is eliminated. This technique provides the ease of consequent daily set-up's and fulfills the requirements for a conformal radiotherapy

  15. Acute toxicity profile of craniospinal irradiation with intensity-modulated radiation therapy in children with medulloblastoma: A prospective analysis

    International Nuclear Information System (INIS)

    Cox, Maurice C.; Kusters, Johannes M.; Gidding, Corrie E.; Schieving, Jolanda H.; Lindert, Erik J. van; Kaanders, Johannes H.; Janssens, Geert O.

    2015-01-01

    To report on the acute toxicity in children with medulloblastoma undergoing intensity-modulated radiation therapy (IMRT) with daily intrafractionally modulated junctions. Newly diagnosed patients, aged 3–21, with standard-risk (SR) or high-risk (HR) medulloblastoma were eligible. A dose of 23.4 or 36.0Gy in daily fractions of 1.8Gy was prescribed to the craniospinal axis, followed by a boost to the primary tumor bed (54 or 55.8Gy) and metastases (39.6–55.8Gy), when indicated. Weekly, an intravenous bolus of vincristine was combined for patients with SR medulloblastoma and patients participating in the COG-ACNS-0332 study. Common toxicity criteria (CTC, version 2.0) focusing on skin, alopecia, voice changes, conjunctivitis, anorexia, dysphagia, gastro-intestinal symptoms, headache, fatigue and hematological changes were scored weekly during radiotherapy. From 2010 to 2014, data from 15 consecutive patients (SR, n = 7; HR, n = 8) were collected. Within 72 h from onset of treatment, vomiting (66 %) and headache (46 %) occurred. During week 3 of treatment, a peak incidence in constipation (33 %) and abdominal pain/cramping (40 %) was observed, but only in the subgroup of patients (n = 9) receiving vincristine (constipation: 56 vs 0 %, P = .04; pain/cramping: 67 vs 0 %, P = .03). At week 6, 73 % of the patients developed faint erythema of the cranial skin with dry desquamation (40 %) or moist desquamation confined to the skin folds of the auricle (33 %). No reaction of the skin overlying the spinal target volume was observed. Headache at onset and gastro-intestinal toxicity, especially in patients receiving weekly vincristine, were the major complaints of patients with medulloblastoma undergoing craniospinal irradiation with IMRT

  16. Comparing conformal, arc radiotherapy and helical tomotherapy in craniospinal irradiation planning.

    Science.gov (United States)

    Myers, Pamela A; Mavroidis, Panayiotis; Papanikolaou, Nikos; Stathakis, Sotirios

    2014-09-08

    Currently, radiotherapy treatment plan acceptance is based primarily on dosimetric performance measures. However, use of radiobiological analysis to assess benefit in terms of tumor control and harm in terms of injury to normal tissues can be advantageous. For pediatric craniospinal axis irradiation (CSI) patients, in particular, knowing the technique that will optimize the probabilities of benefit versus injury can lead to better long-term outcomes. Twenty-four CSI pediatric patients (median age 10) were retrospectively planned with three techniques: three-dimensional conformal radiation therapy (3D CRT), volumetric-modulated arc therapy (VMAT), and helical tomotherapy (HT). VMAT plans consisted of one superior and one inferior full arc, and tomotherapy plans were created using a 5.02cm field width and helical pitch of 0.287. Each plan was normalized to 95% of target volume (whole brain and spinal cord) receiving prescription dose 23.4Gy in 13 fractions. Using an in-house MATLAB code and DVH data from each plan, the three techniques were evaluated based on biologically effective uniform dose (D=), the complication-free tumor control probability (P+), and the width of the therapeutically beneficial range. Overall, 3D CRT and VMAT plans had similar values of D= (24.1 and 24.2 Gy), while HT had a D= slightly lower (23.6 Gy). The average values of the P+ index were 64.6, 67.4, and 56.6% for 3D CRT, VMAT, and HT plans, respectively, with the VMAT plans having a statistically significant increase in P+. Optimal values of D= were 28.4, 33.0, and 31.9 Gy for 3D CRT, VMAT, and HT plans, respectively. Although P+ values that correspond to the initial dose prescription were lower for HT, after optimizing the D= prescription level, the optimal P+ became 94.1, 99.5, and 99.6% for 3D CRT, VMAT, and HT, respectively, with the VMAT and HT plans having statistically significant increases in P+. If the optimal dose level is prescribed using a radiobiological evaluation method, as

  17. Frontal recurrence of medulloblastoma five years after excision and craniospinal irradiation

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    Roka Y

    2009-07-01

    Full Text Available Medulloblastomas were originally classified under gliomas of the cerebellum until Bailey and Cushing in 1925 named these tumors as medulloblastoma. At present these tumors are classified under primitive neuroectodermal tumor. Surgical excision followed by craniospinal irradiation is the treatment of choice. A 13-year-old-girl operated for posterior fossa medulloblastoma 5 years ago presented with history of headache and vomiting on and off for 4 days in late August 2008. The MRI showed left frontal tumor which on excision was reported as medulloblastoma. Even after optimal treatment reports of recurrence abound in literature. The most common location is in the posterior fossa, followed by spinal, supratentorial, and uncommonly, systemic metastases. We conclude that medulloblastomas are highly aggressive tumor with high local recurrences if the initial excision is incomplete and that recurrence in the supratentorial area although uncommon is still a possibility. This mandates regular follow up of these children till adulthood to catch early recurrences and metastatic disease.

  18. Field-In-Field Technique With Intrafractionally Modulated Junction Shifts for Craniospinal Irradiation

    International Nuclear Information System (INIS)

    Yom, Sue S.; Frija, Erik K. C.; Mahajan, Anita; Chang, Eric; Klein, Kelli C.; Shiu, Almon; Ohrt, Jared; Woo, Shiao

    2007-01-01

    Purpose: To plan craniospinal irradiation with 'field-in-field' (FIF) homogenization in combination with daily, intrafractional modulation of the field junctions, to minimize the possibility of spinal cord overdose. Methods and Materials: Lateral cranial fields and posterior spinal fields were planned using a forward-planned, step-and-shoot FIF technique. Field junctions were automatically modulated and custom-weighted for maximal homogeneity within each treatment fraction. Dose-volume histogram analyses and film dosimetry were used to assess results. Results: Plan inhomogeneity improved with FIF. Planning with daily modulated junction shifts provided consistent dose delivery during each fraction of treatment across the junctions. Modulation minimized the impact of a 5-mm setup error at the junction. Film dosimetry confirmed that no point in the junction exceeded the anticipated dose. Conclusions: Field-in-field planning and modulated junction shifts improve the homogeneity and consistency of daily dose delivery, simplify treatment, and reduce the impact of setup errors

  19. Response to growth hormone treatment and final height after cranial or craniospinal irradiation

    International Nuclear Information System (INIS)

    Sulmont, V.; Brauner, R.; Fontoura, M.; Rappaport, R.

    1990-01-01

    Growth hormone (GH) deficiency (GHD) induced by cranial irradiation has become a frequent indication of hGH substitutive therapy. This study analyses the growth response to hGH therapy and the factors involved in the decrease in growth velocity observed after cranial irradiation. One hundred children given cranial radiation for pathology distant from the hypothalamo-pituitary area were studied. Fifty-six of them received hGH therapy for GHD resulting in decreased growth velocity. The initial annual height gain in the cranial-irradiated group was comparable to that of patients treated for idiopathic GHD; additional spinal irradiation significantly reduced the growth response. Twenty-eight hGH-treated patients reached final heights which were compared to those of 2 untreated irradiated groups, one with GHD (n=27) and the other with normal GH secretion (n=17). The height SD score changes observed in hGH therapy were +0.3 in the cranial (n=10) and -1.2 SD in the craniospinal (n=18) groups. GH deficiency had contributed to a mean height loss of 1 SD and spinal irradiation to a loss of 1.4SD. The small effect of hGH therapy on final height is probably linked to the small bone age retardation at onset of hGH therapy and to the fact that irradiated children entered puberty at a younger age in terms of chronological age and bone age than the idiopathic GHD patients. These data suggest that the results of gGH therapy in irradiated children might be improved with higher and more fractionated hGH doses and, in some patients, by delaying puberty using luteinizing hormone releasing hormone analogs

  20. Local Setup Reproducibility of the Spinal Column When Using Intensity-Modulated Radiation Therapy for Craniospinal Irradiation With Patient in Supine Position

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    Stoiber, Eva Maria, E-mail: eva.stoiber@med.uni-heidelberg.de [Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg (Germany); Department of Medical Physics, German Cancer Research Center, Heidelberg (Germany); Giske, Kristina [Department of Medical Physics, German Cancer Research Center, Heidelberg (Germany); Schubert, Kai; Sterzing, Florian; Habl, Gregor; Uhl, Matthias; Herfarth, Klaus [Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg (Germany); Bendl, Rolf [Department of Medical Physics, German Cancer Research Center, Heidelberg (Germany); Medical Informatics, Heilbronn University, Heilbronn (Germany); Debus, Juergen [Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg (Germany)

    2011-12-01

    Purpose: To evaluate local positioning errors of the lumbar spine during fractionated intensity-modulated radiotherapy of patients treated with craniospinal irradiation and to assess the impact of rotational error correction on these uncertainties for one patient setup correction strategy. Methods and Materials: 8 patients (6 adults, 2 children) treated with helical tomotherapy for craniospinal irradiation were retrospectively chosen for this analysis. Patients were immobilized with a deep-drawn Aquaplast head mask. Additionally to daily megavoltage control computed tomography scans of the skull, once-a-week positioning of the lumbar spine was assessed. Therefore, patient setup was corrected by a target point correction, derived from a registration of the patient's skull. The residual positioning variations of the lumbar spine were evaluated applying a rigid-registration algorithm. The impact of different rotational error corrections was simulated. Results: After target point correction, residual local positioning errors of the lumbar spine varied considerably. Craniocaudal axis rotational error correction did not improve or deteriorate these translational errors, whereas simulation of a rotational error correction of the right-left and anterior-posterior axis increased these errors by a factor of 2 to 3. Conclusion: The patient fixation used allows for deformations between the patient's skull and spine. Therefore, for the setup correction strategy evaluated in this study, generous margins for the lumbar spinal target volume are needed to prevent a local geographic miss. With any applied correction strategy, it needs to be evaluated whether or not a rotational error correction is beneficial.

  1. The Parotid Gland is an Underrecognized Organ at Risk for Craniospinal Irradiation.

    Science.gov (United States)

    King, Martin T; Modlin, Leslie; Million, Lynn; Donaldson, Sarah S; Gibbs, Iris C; Choi, Clara Y H; Soltys, Scott G

    2016-06-01

    Current craniospinal irradiation (CSI) protocols do not include the parotid gland as an organ at risk, potentially leading to late effects of xerostomia and secondary parotid malignancies. We analyzed the effect of CSI treatment parameters on parotid dose. We retrospectively reviewed 50 consecutive patients treated with CSI to an intracranial dose >26 Gy. Parotid dose was compared to a Radiation Therapy Oncology Group (RTOG) dose constraint (at least 1 parotid with mean dose parotid dose were analyzed using multivariate regression analysis. The RTOG parotid dose constraint was exceeded in 22 (44%) of 50 patients. On multivariate regression analysis, lower CSI dose and VMAT CSI technique were associated with reduced parotid dose for the CSI fields. For the boost fields, lower boost dose and supratentorial boost location were associated with lower parotid dose. All 5 patients who underwent VMAT CSI met dose constraints. Furthermore, for infratentorial lesions with a total (CSI plus boost) dose prescription dose >50 Gy (n = 24), 11 of 16 patients who received low-dose CSI (18-23.4 Gy) were able to meet dose constraints, when compared to only 2 of 8 patients who received high dose CSI (36 Gy). Given the large number of patients exceeding the parotid dose constraint, the parotid gland should be considered an organ at risk. CSI dose de-escalation and IMRT-based CSI techniques may minimize the risk of xerostomia. © The Author(s) 2015.

  2. Technical study of craniospinal irradiation in pediatric patients with patient position and field matching

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Masanori; Ise, Toshihide; Umezu, Mikio [Kangawa Children' s Medical Center, Yokohama (Japan); Hioki, Minoru

    2000-05-01

    Craniospinal irradiation (CSI) in leukemia and medulloblastoma patients is usually a three-field technique that involves parallel-opposed lateral cranial fields adjacent and orthogonal to a posterior spinal field. Since sedation is often necessary for pediatric patients, the supine position is more favorable than the prone position for respiratory monitoring. We practiced CSI in the supine position in one case of leukemia and three cases of medulloblastoma. Each location of the isocenter was determined by moving the couch to fit the center of the CSI on the basis of incisura intertragica. The angles of collimator rotation and couch rotation were calculated according to each treatment field size. The junction was also moved 2 cm day by day during the course of treatment so that over- and underdose at the junction would be prevented. The supine position did not allow us to visually confirm the proper junction between the lateral cranial fields and the spinal field. However, we succeeded in practicing complete conjunction between the fields by proper collimator and couch rotations on the assessment of the film-dose method. CSI in the supine position is naturally comfortable for pediatric patients and seems effective in pediatric treatments, which often require respiratory monitoring for sedation. (author)

  3. Technical study of craniospinal irradiation in pediatric patients with patient position and field matching

    International Nuclear Information System (INIS)

    Itoh, Masanori; Ise, Toshihide; Umezu, Mikio; Hioki, Minoru

    2000-01-01

    Craniospinal irradiation (CSI) in leukemia and medulloblastoma patients is usually a three-field technique that involves parallel-opposed lateral cranial fields adjacent and orthogonal to a posterior spinal field. Since sedation is often necessary for pediatric patients, the supine position is more favorable than the prone position for respiratory monitoring. We practiced CSI in the supine position in one case of leukemia and three cases of medulloblastoma. Each location of the isocenter was determined by moving the couch to fit the center of the CSI on the basis of incisura intertragica. The angles of collimator rotation and couch rotation were calculated according to each treatment field size. The junction was also moved 2 cm day by day during the course of treatment so that over- and underdose at the junction would be prevented. The supine position did not allow us to visually confirm the proper junction between the lateral cranial fields and the spinal field. However, we succeeded in practicing complete conjunction between the fields by proper collimator and couch rotations on the assessment of the film-dose method. CSI in the supine position is naturally comfortable for pediatric patients and seems effective in pediatric treatments, which often require respiratory monitoring for sedation. (author)

  4. Comparison of supine and prone craniospinal irradiation in children with medulloblastoma.

    Science.gov (United States)

    Verma, Jonathan; Mazloom, Ali; Teh, Bin S; South, Michael; Butler, E Brian; Paulino, Arnold C

    2015-01-01

    To compare port film rejection and treatment outcome according to craniospinal irradiation (CSI) position for medulloblastoma. We retrospectively searched for patients ≤19 years treated with CSI for medulloblastoma at 1 department. We collected the following data: age; sex; risk group; need for general anesthesia; radiation therapy (RT) dose and fractionation; and the acceptance or rejection of weekly port films during treatment. We also collected data on outcomes, including neuraxis recurrence and possible complications such as myelitis. Of 46 children identified, 23 were treated prone (median age, 8.1 years) and 23 supine (median age, 7.2 years). High-risk disease was seen in 26% of prone and 35% of supine patients (P = .25). There was no difference in use of general anesthesia between those treated prone versus supine (57% vs 61%). The rejection rate of cranial port films in the prone position was 35%, which was significantly higher than the rate of 8% in patients treated supine (P < .0001). The 5-year progression-free (P = .37) and overall survival (P = .18) rates were 62% and 67% for prone and 76% and 84% for supine patients. There were no isolated junctional failures or radiation myelitis in either CSI position. The supine position for CSI was found to have similar survival outcomes compared with the prone position. A higher proportion of rejected cranial port films was seen in children treated in the prone position. Copyright © 2015 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

  5. Physiologic and Radiographic Evidence of the Distal Edge of the Proton Beam in Craniospinal Irradiation

    International Nuclear Information System (INIS)

    Krejcarek, Stephanie C.; Grant, P. Ellen; Henson, John W.; Tarbell, Nancy J.; Yock, Torunn I.

    2007-01-01

    Purpose: Fatty replacement of bone marrow resulting from radiation therapy can be seen on T1-weighted magnetic resonance (MR) images. We evaluated the radiographic appearance of the vertebral bodies in children treated with proton craniospinal irradiation (CSI) to illustrate the distal edge effect of proton radiotherapy. Methods and Materials: The study cohort consisted of 13 adolescents aged 12-18 years who received CSI with proton radiotherapy at Massachusetts General Hospital. Ten of these patients had reached maximal or near-maximal growth. Proton beam radiation for these 10 patients was delivered to the thecal sac and exiting nerve roots only, whereas the remaining 3 patients had a target volume that included the thecal sac, exiting nerve roots, and entire vertebral bodies. Median CSI dose was 27 [range, 23.4-36] cobalt gray equivalent (CGE) given in 1.8-CGE fractions. Magnetic resonance images of the spine were obtained after completion of radiotherapy. Results: Magnetic resonance images of patients who received proton radiotherapy to the thecal sac only demonstrate a sharp demarcation of hyperintense T1-weighted signal in the posterior aspects of the vertebral bodies, consistent with radiation-associated fatty marrow replacement. Magnetic resonance images of the patients prescribed proton radiotherapy to the entire vertebral column had corresponding hyperintense T1-weighted signal involving the entire vertebral bodies. Conclusion: The sharp delineation of radiation-associated fatty marrow replacement in the vertebral bodies demonstrates the rapid decrease in energy at the edge of the proton beam. This provides evidence for a sharp fall-off in radiation dose and supports the premise that proton radiotherapy spares normal tissues unnecessary irradiation

  6. Craniospinal irradiation with concurrent temozolomide for primary metastatic pediatric high-grade or diffuse intrinsic pontine gliomas. A first report from the GPOH-HIT-HGG Study Group

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, K.; Schlamann, A.; Pietschmann, S.; Kortmann, R.D. [University Medical Center Leipzig, Department of Radiation Oncology, Leipzig (Germany); Guckenberger, M. [University Medical Center Wuerzburg, Department of Radiation Oncology, Wuerzburg (Germany); Warmuth-Metz, M. [University Medical Center Wuerzburg, Department of Neuroradiology, Wuerzburg (Germany); Glueck, A. [Clinic for Radiation Oncology Schwabing, Muenchen (Germany); Wawer, A. [University Medical Center Muenchen Schwabing, Department of Pediatric Hematology and Oncology, Muenchen (Germany); Kramm, C.; Bueren, A.O. von [University Medical Center Goettingen, Division of Pediatric Hematology and Oncology, Department of Pediatrics and Adolescent Medicine, Goettingen (Germany)

    2014-04-15

    High-grade (HGG) and diffuse intrinsic pontine gliomas (DIPG) with primary metastatic spread are extremely rare and have a dismal prognosis. Analogous to simultaneous radiochemotherapy in non-metastatic HGG and DIPG, concurrent craniospinal irradiation (CSI) and metronomic temozolomide (metroTMZ) may represent a reasonable therapeutic approach. However, the antitumor efficacy and toxicity of this treatment still have to be investigated. Between March 2007 and December 2012, six children with primary metastatic HGG (n=4) or DIPG (n=2) received CSI and concurrent metroTMZ based on individual treatment recommendations and, in some cases, within the HIT-HGG 2007 multicenter trial. Outcome and treatment-related toxicities were evaluated. All patients received irradiation to the entire craniospinal axis (35.2 Gy, n=5; 36 Gy, n=1:) and 5 received a local boost to macroscopic tumor deposits. Simultaneously, metroTMZ (75 mg/m{sup 2}/day, n=5; 60 mg/m{sup 2}/day, n=1) was administered. Additionally, 1 patient received nimotuzumab once per week. Within a median follow-up of 10.0 months (range 6.5-18.7 months), all patients experienced disease progression and 5 patients died. Median progression-free survival was 4.0±0.8 months (range 2.4-10.7 months) and median overall survival was 7.6±3.5 months (range 4.0-17.6 months). Acute myelosuppression most severely limited application of this aggressive treatment strategy. Severe hematotoxicities (= grade 3) occurred in all patients and metroTMZ had to be interrupted or discontinued in 4 out of 6 cases. Concurrent CSI and metroTMZ might represent a feasible treatment approach for primary metastatic HGG and DIPG. On the basis of our experience, severe but manageable acute hematotoxicity has to be expected. An international effort is warranted to reassess the efficacy and toxicity of this approach within a prospective study. (orig.)

  7. Updated results of a pilot study of low dose craniospinal irradiation plus chemotherapy for children under five with cerebellar primitive neuroectodermal tumors (medulloblastoma)

    International Nuclear Information System (INIS)

    Goldwein, Joel W.; Radcliffe, Jerilynn; Johnson, James; Moshang, Thomas; Packer, Roger J.; Sutton, Leslie N.; Rorke, Lucy B.; D'Angio, Giulio J.

    1996-01-01

    Purpose: Children under 5 years old with medulloblastoma (MB) have a poor prognosis. They are more susceptible to the deleterious effects of craniospinal irradiation (CSART) and have a higher relapse rate when treated with low-dose CSART alone. We, thus, embarked on a prospective trial testing the usefulness of very low dose CSART and adjuvant chemotherapy. This is an update of a previous report on these patients. Methods and Materials: Between January 1988 and March 1990, 10 patients with medulloblastoma were treated using 18 Gy radiation therapy (RT) to the craniospinal axis, a posterior fossa (PF) boost to 50.4-55.8 Gy and chemotherapy consisting of vincristine (VCR) weekly during RT. This was followed by VCR, cis-diamminedichloroplatinum (CDDP), and lomustine (CCNU) for eight, 6-week cycles. Patients between 18 and 60 months of age without evidence of tumor dissemination were eligible for study. Follow-up was available until September 1994 with a median follow-up for living patients of 6.3 years from diagnosis. Results: Actuarial survival at over 6 years is 70 ± 20%. Three of the 10 patients relapsed and died. In one patient, the relapse developed in the spine and brain outside the posterior fossa, in the second, concurrently in the posterior fossa, brain and spine, and the third, only in the spine. One surviving child developed a brain stem infarct 4.8 years after diagnosis and has since almost fully recovered. A mean intelligence quotient (IQ) score of 103 in six patients surviving at least 1 year is unchanged from the baseline group score of 107. Five children tested at baseline and 2 years following treatment had IQ scores of 101 and 102, respectively. Six children tested at baseline and at 3 years had IQ scores of 106 and 96, respectively. Excluding the child tested shortly after his brain stem infarct, baseline and 3 year IQ scores were 103 and 97, respectively. Five of the seven long-term survivors grew at rates significantly below their expected

  8. SU-F-T-504: Non-Divergent Planning Method for Craniospinal Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Sperling, N; Bogue, J; Parsai, E [University of Toledo Medical Center, Toledo, OH (United States)

    2016-06-15

    Purpose: Traditional Craniospinal Irradiation (CSI) planning techniques require careful field placement to allow optimal divergence and field overlap at depth, and measurement of skin gap. The result of this is a necessary field overlap resulting in dose heterogeneity in the spinal canal. A novel, nondivergent field matching method has been developed to allow simple treatment planning and delivery without the need to measure skin gap. Methods: The CSI patient was simulated in the prone, and a plan was developed. Bilateral cranial fields were designed with couch and collimator rotation to eliminate divergence with the upper spine field and minimize anterior divergence into the lenses. Spinal posterior-to-anterior fields were designed with the couch rotated to 90 degrees to allow gantry rotation to eliminate divergence at the match line, and the collimator rotated to 90 degrees to allow appropriate field blocking with the MLCs. A match line for the two spinal fields was placed and the gantry rotated to equal angles in opposite directions about the match line. Jaw positions were then defined to allow 1mm overlap at the match line to avoid cold spots. A traditional CSI plan was generated using diverging spinal fields, and a comparison between the two techniques was generated. Results: The non-divergent treatment plan was able to deliver a highly uniform dose to the spinal cord with a cold spot of only 95% and maximum point dose of 115.8%, as compared to traditional plan cold spots of 87% and hot spots of 132% of the prescription dose. Conclusion: A non-divergent method for planning CSI patients has been developed and clinically implemented. Planning requires some geometric manipulation in order to achieve an adequate dose distribution, however, it can help to manage cold spots and simplify the shifts needed between spinal fields.

  9. Proton Beam Craniospinal Irradiation Reduces Acute Toxicity for Adults With Medulloblastoma

    International Nuclear Information System (INIS)

    Brown, Aaron P.; Barney, Christian L.; Grosshans, David R.; McAleer, Mary Frances; Groot, John F. de; Puduvalli, Vinay K.; Tucker, Susan L.; Crawford, Cody N.; Khan, Meena; Khatua, Soumen; Gilbert, Mark R.; Brown, Paul D.; Mahajan, Anita

    2013-01-01

    Purpose: Efficacy and acute toxicity of proton craniospinal irradiation (p-CSI) were compared with conventional photon CSI (x-CSI) for adults with medulloblastoma. Methods and Materials: Forty adult medulloblastoma patients treated with x-CSI (n=21) or p-CSI (n=19) at the University of Texas MD Anderson Cancer Center from 2003 to 2011 were retrospectively reviewed. Median CSI and total doses were 30.6 and 54 Gy, respectively. The median follow-up was 57 months (range 4-103) for x-CSI patients and 26 months (range 11-63) for p-CSI. Results: p-CSI patients lost less weight than x-CSI patients (1.2% vs 5.8%; P=.004), and less p-CSI patients had >5% weight loss compared with x-CSI (16% vs 64%; P=.004). p-CSI patients experienced less grade 2 nausea and vomiting compared with x-CSI (26% vs 71%; P=.004). Patients treated with x-CSI were more likely to have medical management of esophagitis than p-CSI patients (57% vs 5%, P<.001). p-CSI patients had a smaller reduction in peripheral white blood cells, hemoglobin, and platelets compared with x-CSI (white blood cells 46% vs 55%, P=.04; hemoglobin 88% vs 97%, P=.009; platelets 48% vs 65%, P=.05). Mean vertebral doses were significantly associated with reductions in blood counts. Conclusions: This report is the first analysis of clinical outcomes for adult medulloblastoma patients treated with p-CSI. Patients treated with p-CSI experienced less treatment-related morbidity including fewer acute gastrointestinal and hematologic toxicities

  10. A simple planning technique of craniospinal irradiation in the eclipse treatment planning system

    Directory of Open Access Journals (Sweden)

    Hemalatha Athiyaman

    2014-01-01

    Full Text Available A new planning method for Craniospinal Irradiation by Eclipse treatment planning system using Field alignment, Field-in-Field technique was developed. Advantage of this planning method was also studied retrospectively for previously treated five patients of medulloblastoma with variable spine length. Plan consists of half beam blocked parallel opposed cranium, and a single posterior cervicospine field was created by sharing the same isocenter, which obviates divergence matching. Further, a single symmetrical field was created to treat remaining Lumbosacral spine. Matching between a inferior diverging edge of cervicospine field and superior diverging edge of a Lumbosacral field was done using the field alignment option. ′Field alignment′ is specific option in the Eclipse Treatment Planning System, which automatically matches the field edge divergence as per field alignment rule. Multiple segments were applied in both the spine field to manage with hot and cold spots created by varying depth of spinal cord. Plan becomes fully computerized using this field alignment option and multiple segments. Plan evaluation and calculated mean modified Homogeneity Index (1.04 and 0.1 ensured that dose to target volume is homogeneous and critical organ doses were within tolerance. Dose variation at the spinal field junction was verified using ionization chamber array (I′MatriXX for matched, overlapped and gap junction spine fields; the delivered dose distribution confirmed the ideal clinical match, over exposure and under exposure at the junction, respectively. This method is simple to plan, executable in Record and Verify mode and can be adopted for various length of spinal cord with only two isocenter in shorter treatment time.

  11. Craniospinal versus whole brain irradiation in Medulloblastoma patients, with introduction of utilizing a simple immobilization device

    Directory of Open Access Journals (Sweden)

    Haddad P

    2001-05-01

    Full Text Available Craniospinal irradiation plus posterior fossa boost (CS1 is the standard modality of post-operative treatment of patient with medulloblastoma, but considering the technical difficulties and limited facilities, often whole- brain irradiation plus posterior fossa boost (WBI had been used in our institution until 1991. Tust a retrospective study was undertaken to compare the patients treated by By WBI and CSI for recurrences and disease-free survival (DFS. Files of all medullobalstoma patients treated post-operatively in our department in the 10 – year period of 1986-1996 were reviewed. To obtain the best possible follow- up, a formal inquiry letter was mailed to all patients’ addresses.Total of 72 patients had been treated, with a mean age of 14.7 years and male-to-female ratio of 1.5:1 Thirty –seven patients had been treated by WBI and 35 by CS. A simple wooden device designed and made in our department was used for CSI patients’ set-up and immobilization. Mean radiation dose to posterior fossa was 4, 765 cGy in WBT and 5, 071 cGY in CSI (180-200 cGy fractions. Sixty-two patients (85% came back for follow-up, with 24 recurrences. Only 24% of CSI patients had recurrences, versus 51% in WBI Nearly all Wbi recurrences versus half of the CSI recurrences were spinal. DFS was 39 months in CSI and 26 months in WBI (P<0.001 . in multi-factorial analysis, only the extent of radiation (CSI versus WBI, P<0.001 was statistically significant. Mean age in our patients was higher than what is commonly reported in literature. The immobilization device introduce was a simple and useful accessory to CSI. Considering DFS, CSI in our department was acceptabley comparable to literature results and significantly superior to WBI. With regard to relatively high spinal recurrence rate even in CSI, the importance of suitable spinal cytological and imaging evaluation is again emphasized.

  12. Late effects of craniospinal irradiation for standard risk medulloblastoma in paediatric patients: A comparison of treatment techniques

    International Nuclear Information System (INIS)

    Leman, J.

    2016-01-01

    Background: Survival rates for standard risk medulloblastoma are favourable, but craniospinal irradiation (CSI) necessary to eradicate microscopic spread causes life limiting late effects. Aims: The aim of this paper is to compare CSI techniques in terms of toxicity and quality of life for survivors. Methods and materials: A literature search was conducted using synonyms of ‘medulloblastoma’, ’craniospinal’, ‘radiotherapy’ and ‘side effects’ to highlight 29 papers that would facilitate this discussion. Results and discussion: Intensity modulated radiotherapy (IMRT), tomotherapy and protons all provide CSI which can reduce dose to normal tissue, however photon methods cannot eliminate exit dose as well as protons can. Research for each technique requires longer term follow up in order to prove that survival rates remain high whilst reducing late effects. Findings/conclusion: Proton therapy is the superior method of CSI in term of late effects, but more research is needed to evidence this. Until proton therapy is available in the UK IMRT should be utilised. - Highlights: • Craniospinal irradiation is vital in the treatment of medulloblastoma. • Survivors often suffer long term side effects which reduce quality of life. • Tomotherapy, IMRT and proton therapy reduce late effects by sparing normal tissue. • Proton therapy offers superior dose distribution but further research is necessary. • IMRT should be employed for photon radiotherapy.

  13. Pulmonary Function After Treatment for Embryonal Brain Tumors on SJMB03 That Included Craniospinal Irradiation

    International Nuclear Information System (INIS)

    Green, Daniel M.; Merchant, Thomas E.; Billups, Catherine A.; Stokes, Dennis C.; Broniscer, Alberto; Bartels, Ute; Chintagumpala, Murali; Hassall, Timothy E.; Gururangan, Sridharan; McCowage, Geoffrey B.; Heath, John A.; Cohn, Richard J.; Fisher, Michael J.; Srinivasan, Ashok; Robinson, Giles W.; Gajjar, Amar

    2015-01-01

    Purpose: The treatment of children with embryonal brain tumors (EBT) includes craniospinal irradiation (CSI). There are limited data regarding the effect of CSI on pulmonary function. Methods: Protocol SJMB03 enrolled patients 3 to 21 years of age with EBT. Pulmonary function tests (PFTs) (forced expiratory volume in 1 second [FEV 1 ] and forced vital capacity [FVC] by spirometry, total lung capacity [TLC] by nitrogen washout or plethysmography, and diffusing capacity of the lung for carbon monoxide corrected for hemoglobin [DLCO corr ]) were obtained. Differences between PFTs obtained immediately after the completion of CSI and 24 or 60 months after the completion of treatment (ACT) were compared using exact Wilcoxon signed-rank tests and repeated-measures models. Results: Between June 24, 2003, and March 1, 2010, 303 eligible patients (spine dose: ≤2345 cGy, 201; >2345 cGy, 102; proton beam, 20) were enrolled, 260 of whom had at least 1 PFT. The median age at diagnosis was 8.9 years (range, 3.1-20.4 years). The median thoracic spinal radiation dose was 23.4 Gy (interquartile range [IQR], 23.4-36.0 Gy). The median cyclophosphamide dose was 16.0 g/m 2 (IQR, 15.7-16.0 g/m 2 ). At 24 and 60 months ACT, DLCO corr was <75% predicted in 23% (27/118) and 25% (21/84) of patients, FEV 1 was <80% predicted in 20% (34/170) and 29% (32/109) of patients, FVC was <80% predicted in 27% (46/172) and 28% (30/108) of patients, and TLC was <75% predicted in 9% (13/138) and 11% (10/92) of patients. DLCO corr was significantly decreased 24 months ACT (median difference [MD] in % predicted, 3.00%; P=.028) and 60 months ACT (MD in % predicted, 6.00%; P=.033) compared with the end of radiation therapy. These significant decreases in DLCO corr were also observed in repeated-measures models (P=.011 and P=.032 at 24 and 60 months ACT, respectively). Conclusions: A significant minority of EBT survivors experience PFT deficits after CSI. Continued monitoring of this cohort

  14. Pulmonary Function After Treatment for Embryonal Brain Tumors on SJMB03 That Included Craniospinal Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Green, Daniel M., E-mail: daniel.green@stjude.org [Department of Epidemiology and Cancer Control, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Merchant, Thomas E. [Department of Radiological Sciences, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Billups, Catherine A. [Department of Biostatistics, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Stokes, Dennis C. [Department of Pediatrics, University of Tennessee School of Medicine, Memphis, Tennessee (United States); Broniscer, Alberto [Department of Oncology, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Bartels, Ute [Department of Haematology and Oncology, The Hospital for Sick Children, Toronto, Ontario (Canada); Chintagumpala, Murali [Department of Pediatric Medicine, Texas Children' s Cancer and Hematology Centers, Baylor College of Medicine, Houston, Texas (United States); Hassall, Timothy E. [Department of Haematology and Oncology, Royal Children' s Hospital, Brisbane (Australia); Gururangan, Sridharan [Department of Pediatrics, Duke University Medical Center, Durham, North Carolina (United States); McCowage, Geoffrey B. [Department of Pediatrics, Children' s Hospital at Westmead, Sydney (Australia); Heath, John A. [Children' s Cancer Center, Royal Children' s Hospital Melbourne, Melbourne (Australia); Cohn, Richard J. [Department of Clinical Oncology, Sydney Children' s Hospital, Sydney (Australia); Fisher, Michael J. [Department of Pediatrics, Children' s Hospital of Philadelphia, Philadelphia, Pennsylvania (United States); Srinivasan, Ashok [Department of Bone Marrow Transplantation & Cellular Therapy, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Robinson, Giles W.; Gajjar, Amar [Department of Oncology, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States)

    2015-09-01

    Purpose: The treatment of children with embryonal brain tumors (EBT) includes craniospinal irradiation (CSI). There are limited data regarding the effect of CSI on pulmonary function. Methods: Protocol SJMB03 enrolled patients 3 to 21 years of age with EBT. Pulmonary function tests (PFTs) (forced expiratory volume in 1 second [FEV{sub 1}] and forced vital capacity [FVC] by spirometry, total lung capacity [TLC] by nitrogen washout or plethysmography, and diffusing capacity of the lung for carbon monoxide corrected for hemoglobin [DLCO{sub corr}]) were obtained. Differences between PFTs obtained immediately after the completion of CSI and 24 or 60 months after the completion of treatment (ACT) were compared using exact Wilcoxon signed-rank tests and repeated-measures models. Results: Between June 24, 2003, and March 1, 2010, 303 eligible patients (spine dose: ≤2345 cGy, 201; >2345 cGy, 102; proton beam, 20) were enrolled, 260 of whom had at least 1 PFT. The median age at diagnosis was 8.9 years (range, 3.1-20.4 years). The median thoracic spinal radiation dose was 23.4 Gy (interquartile range [IQR], 23.4-36.0 Gy). The median cyclophosphamide dose was 16.0 g/m{sup 2} (IQR, 15.7-16.0 g/m{sup 2}). At 24 and 60 months ACT, DLCO{sub corr} was <75% predicted in 23% (27/118) and 25% (21/84) of patients, FEV{sub 1} was <80% predicted in 20% (34/170) and 29% (32/109) of patients, FVC was <80% predicted in 27% (46/172) and 28% (30/108) of patients, and TLC was <75% predicted in 9% (13/138) and 11% (10/92) of patients. DLCO{sub corr} was significantly decreased 24 months ACT (median difference [MD] in % predicted, 3.00%; P=.028) and 60 months ACT (MD in % predicted, 6.00%; P=.033) compared with the end of radiation therapy. These significant decreases in DLCO{sub corr} were also observed in repeated-measures models (P=.011 and P=.032 at 24 and 60 months ACT, respectively). Conclusions: A significant minority of EBT survivors experience PFT deficits after CSI

  15. Comparison of therapeutic dosimetric data from passively scattered proton and photon craniospinal irradiations for medulloblastoma

    Directory of Open Access Journals (Sweden)

    Howell Rebecca M

    2012-07-01

    Full Text Available Abstract Background For many decades, the standard of care radiotherapy regimen for medulloblastoma has been photon (megavoltage x-rays craniospinal irradiation (CSI. The late effects associated with CSI are well-documented in the literature and are in-part attributed to unwanted dose to healthy tissue. Recently, there is growing interest in using proton therapy for CSI in pediatric and adolescent patients to reduce this undesirable dose. Previous comparisons of dose to target and non-target organs from conventional photon CSI and passively scattered proton CSI have been limited to small populations (n ≤ 3 and have not considered the use of age-dependent target volumes in proton CSI. Methods Standard of care treatment plans were developed for both photon and proton CSI for 18 patients. This cohort included both male and female medulloblastoma patients whose ages, heights, and weights spanned a clinically relevant and representative spectrum (age 2–16, BMI 16.4–37.9 kg/m2. Differences in plans were evaluated using Wilcoxon signed rank tests for various dosimetric parameters for the target volumes and normal tissue. Results Proton CSI improved normal tissue sparing while also providing more homogeneous target coverage than photon CSI for patients across a wide age and BMI spectrum. Of the 24 parameters (V5, V10, V15, and V20 in the esophagus, heart, liver, thyroid, kidneys, and lungs Wilcoxon signed rank test results indicated 20 were significantly higher for photon CSI compared to proton CSI (p ≤ 0.05 . Specifically, V15 and V20 in all six organs and V5, V10 in the esophagus, heart, liver, and thyroid were significantly higher with photon CSI. Conclusions Our patient cohort is the largest, to date, in which CSI with proton and photon therapies have been compared. This work adds to the body of literature that proton CSI reduces dose to normal tissue compared to photon CSI for pediatric patients who are at substantial risk for

  16. SU-F-T-515: Increased Skin Dose in Supine Craniospinal Irradiation Due to Carbon Fiber Couch and Vacuum Bag Immobilization Device

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, D; Zhao, Z; Wang, X; Yang, J [UT MD Anderson Cancer Center, Houston, TX (United States)

    2016-06-15

    Purpose: To measure the surface dose for supine craniospinal irradiation employing posterior beams, treating through an imaging couch and BlueBag immobilization device. Methods: The percentage depth dose (PDD) in the buildup region of a clinical 6 MV photon beam was measured using an Advanced Markus parallel plate ionization chamber in a solid water phantom. The PDD from a 10×10 cm{sup 2} anterior beam was measured at 100 cm SSD, simulating a traditional prone craniospinal technique. The measurements were compared to commissioning and treatment planning system data. The PDD was also measured in a posterior setup with the phantom surface laying directly on the Brainlab carbon fiber imaging couch, with the phantom surface 100 cm from the source, simulating a supine craniospinal setup. The posterior measurements were repeated with a BlueBag vacuum immobilization device between the couch and phantom, with thicknesses of 1.7 cm and 5 cm. The PDD from a 10×10 cm{sup 2} field and a typical 6×30 cm{sup 2} craniospinal field were also compared. The PDDs were normalized at 5 cm to reflect typical craniospinal prescription dose normalization. Results: The measured PDD curve from the anterior setup agreed well with commissioning and treatment planning data, with surface doses of 19.9%, 28.8% and 27.7%, respectively. The surface doses of the 10×10 cm{sup 2} and 6×30 cm{sup 2} fields delivered through the imaging couch were both 122.4%. The supine setup yielded surface doses of 122.4%, 121.6%, and 119.6% for the couch only, 1.7 cm bag, and 5 cm bag setups, respectively. Conclusion: Delivering craniospinal irradiation through a carbon fiber couch removes the majority of skin sparing. The addition of a vacuum bag immobilization device restores some skin sparing, but the magnitude of this effect is negligible.

  17. Comparison of a new noncoplanar intensity-modulated radiation therapy technique for craniospinal irradiation with 3 coplanar techniques

    DEFF Research Database (Denmark)

    Hansen, Anders T; Lukacova, Slavka; Lassen-Ramshad, Yasmin A.

    2015-01-01

    When standard conformal x-ray technique for craniospinal irradiation is used, it is a challenge to achieve satisfactory dose coverage of the target including the area of the cribriform plate, while sparing organs at risk. We present a new intensity-modulated radiation therapy (IMRT), noncoplanar...... patient using the noncoplanar IMRT-based technique, a coplanar IMRT-based technique, and a coplanar volumetric-modulated arch therapy (VMAT) technique. Dosimetry data for all patients were compared with the corresponding data from the conventional treatment plans. The new noncoplanar IMRT technique...... substantially reduced the mean dose to organs at risk compared with the standard radiation technique. The 2 other coplanar techniques also reduced the mean dose to some of the critical organs. However, this reduction was not as substantial as the reduction obtained by the noncoplanar technique. Furthermore...

  18. Comparison of risk of radiogenic second cancer following photon and proton craniospinal irradiation for a pediatric medulloblastoma patient

    Science.gov (United States)

    Zhang, Rui; Howell, Rebecca M.; Giebeler, Annelise; Taddei, Phillip J.; Mahajan, Anita; Newhauser, Wayne D.

    2013-02-01

    Pediatric patients who received radiation therapy are at risk of developing side effects such as radiogenic second cancer. We compared proton and photon therapies in terms of the predicted risk of second cancers for a 4 year old medulloblastoma patient receiving craniospinal irradiation (CSI). Two CSI treatment plans with 23.4 Gy or Gy (RBE) prescribed dose were computed: a three-field 6 MV photon therapy plan and a four-field proton therapy plan. The primary doses for both plans were determined using a commercial treatment planning system. Stray radiation doses for proton therapy were determined from Monte Carlo simulations, and stray radiation doses for photon therapy were determined from measured data. Dose-risk models based on the Biological Effects of Ionization Radiation VII report were used to estimate the risk of second cancer in eight tissues/organs. Baseline predictions of the relative risk for each organ were always less for proton CSI than for photon CSI at all attained ages. The total lifetime attributable risk of the incidence of second cancer considered after proton CSI was much lower than that after photon CSI, and the ratio of lifetime risk was 0.18. Uncertainty analysis revealed that the qualitative findings of this study were insensitive to any plausible changes of dose-risk models and mean radiation weighting factor for neutrons. Proton therapy confers lower predicted risk of second cancer than photon therapy for the pediatric medulloblastoma patient.

  19. Survival and Neurocognitive Outcomes After Cranial or Craniospinal Irradiation Plus Total-Body Irradiation Before Stem Cell Transplantation in Pediatric Leukemia Patients With Central Nervous System Involvement

    International Nuclear Information System (INIS)

    Hiniker, Susan M.; Agarwal, Rajni; Modlin, Leslie A.; Gray, Christine C.; Harris, Jeremy P.; Million, Lynn; Kiamanesh, Eileen F.; Donaldson, Sarah S.

    2014-01-01

    Purpose: To evaluate survival and neurocognitive outcomes in pediatric acute lymphoblastic leukemia (ALL) patients with central nervous system (CNS) involvement treated according to an institutional protocol with stem cell transplantation (SCT) and a component of craniospinal irradiation (CSI) in addition to total-body irradiation (TBI) as preparative regimen. Methods and Materials: Forty-one pediatric ALL patients underwent SCT with TBI and received additional cranial irradiation or CSI because of CNS leukemic involvement. Prospective neurocognitive testing was performed before and after SCT in a subset of patients. Cox regression models were used to determine associations of patient and disease characteristics and treatment methods with outcomes. Results: All patients received a cranial radiation boost; median total cranial dose was 24 Gy. Eighteen patients (44%) received a spinal boost; median total spinal dose for these patients was 18 Gy. Five-year disease-free survival (DFS) for all patients was 67%. Those receiving CSI had a trend toward superior DFS compared with those receiving a cranial boost alone (hazard ratio 3.23, P=.14). Patients with isolated CNS disease before SCT had a trend toward superior DFS (hazard ratio 3.64, P=.11, 5-year DFS 74%) compared with those with combined CNS and bone marrow disease (5-year DFS 59%). Neurocognitive testing revealed a mean post-SCT overall intelligence quotient of 103.7 at 4.4 years. Relative deficiencies in processing speed and/or working memory were noted in 6 of 16 tested patients (38%). Pre- and post-SCT neurocognitive testing revealed no significant change in intelligence quotient (mean increase +4.7 points). At a mean of 12.5 years after transplant, 11 of 13 long-term survivors (85%) had completed at least some coursework at a 2- or 4-year college. Conclusion: The addition of CSI to TBI before SCT in pediatric ALL with CNS involvement is effective and well-tolerated. Craniospinal irradiation plus TBI is worthy

  20. Survival and Neurocognitive Outcomes After Cranial or Craniospinal Irradiation Plus Total-Body Irradiation Before Stem Cell Transplantation in Pediatric Leukemia Patients With Central Nervous System Involvement

    Energy Technology Data Exchange (ETDEWEB)

    Hiniker, Susan M. [Department of Radiation Oncology, Stanford University, Stanford, California (United States); Agarwal, Rajni [Section of Stem Cell Transplantation, Department of Pediatrics, Stanford University, Stanford, California (United States); Modlin, Leslie A. [Department of Radiation Oncology, Stanford University, Stanford, California (United States); Gray, Christine C. [Division of Child and Adolescent Psychiatry, Department of Psychiatry, Stanford University, Stanford, California (United States); Harris, Jeremy P.; Million, Lynn [Department of Radiation Oncology, Stanford University, Stanford, California (United States); Kiamanesh, Eileen F. [Cancer Clinical Trials Office, Stanford Cancer Institute, Stanford University, Stanford, California (United States); Donaldson, Sarah S., E-mail: sarah2@stanford.edu [Department of Radiation Oncology, Stanford University, Stanford, California (United States)

    2014-05-01

    Purpose: To evaluate survival and neurocognitive outcomes in pediatric acute lymphoblastic leukemia (ALL) patients with central nervous system (CNS) involvement treated according to an institutional protocol with stem cell transplantation (SCT) and a component of craniospinal irradiation (CSI) in addition to total-body irradiation (TBI) as preparative regimen. Methods and Materials: Forty-one pediatric ALL patients underwent SCT with TBI and received additional cranial irradiation or CSI because of CNS leukemic involvement. Prospective neurocognitive testing was performed before and after SCT in a subset of patients. Cox regression models were used to determine associations of patient and disease characteristics and treatment methods with outcomes. Results: All patients received a cranial radiation boost; median total cranial dose was 24 Gy. Eighteen patients (44%) received a spinal boost; median total spinal dose for these patients was 18 Gy. Five-year disease-free survival (DFS) for all patients was 67%. Those receiving CSI had a trend toward superior DFS compared with those receiving a cranial boost alone (hazard ratio 3.23, P=.14). Patients with isolated CNS disease before SCT had a trend toward superior DFS (hazard ratio 3.64, P=.11, 5-year DFS 74%) compared with those with combined CNS and bone marrow disease (5-year DFS 59%). Neurocognitive testing revealed a mean post-SCT overall intelligence quotient of 103.7 at 4.4 years. Relative deficiencies in processing speed and/or working memory were noted in 6 of 16 tested patients (38%). Pre- and post-SCT neurocognitive testing revealed no significant change in intelligence quotient (mean increase +4.7 points). At a mean of 12.5 years after transplant, 11 of 13 long-term survivors (85%) had completed at least some coursework at a 2- or 4-year college. Conclusion: The addition of CSI to TBI before SCT in pediatric ALL with CNS involvement is effective and well-tolerated. Craniospinal irradiation plus TBI is worthy

  1. SU-F-T-446: Improving Craniospinal Irradiation Technique Using Volumetric Modulated Arc Therapy (VMAT) Planning and Its Dosimetric Verification

    Energy Technology Data Exchange (ETDEWEB)

    Yang, X; Tejani, M; Jiang, X; Elder, E; Dhabaan, A [Emory University, Atlanta, GA (United States)

    2016-06-15

    Purpose: The purpose of this study is to investigate a volumetric modulated arc therapy (VMAT) treatment planning technique for supine craniospinal irradiation (CSI). Evaluate the suitability of VMAT for CSI with dosimetric measurements and compare it to 3D conformal planning using specific plan metrics such as dose conformity, homogeneity, and dose of organs at risk (OAR). Methods: Ten CSI patients treated with conventional 3D technique were re-planned with VMAT. The PTV was contoured to include the whole contents of the brain and spinal canal with a uniform margin of 5 mm. VMAT plans were generated with two partial arcs covering the brain, two partial arcs for the superior portion of the spinal cord and two partial arcs covering the remaining inferior portion of the spinal cord. Conformity index (CI), heterogeneity indexes (HI) and max and mean doses of OAR were compared to 3D plans. VMAT plans were delivered onto an anthropomorphic phantom loaded with Gafchromic films and OSLDs placed at specific positions to evaluate the plan dose at the junctions and as well as the plan dose distributions. Results: This VMAT technique was validated with a clinical study of 10 patients. The average CI was 1.03±0.02 for VMAT plans and 1.96±0.32 for conformal plans. And the average HI was 1.15±0.01 for VMAT plans and 1.51±0.21 for conformal plans. The mean and max doses to the all OARs for VMAT plans were significantly lower than conformal plans. The measured dose in phantom for VAMT plans was comparable to the calculated dose in Eclipse and the doses at junctions were verified. Conclusion: VMAT CSI was able to achieve better dose conformity and heterogeneity as well as significantly reducing the dose to Heart, esophagus and larynx. VMAT CSI appears to be a dosimterically advantageous, faster delivery, has better reproducibility CSI treatment.

  2. Collimator rotation in volumetric modulated arc therapy for craniospinal irradiation and the dose distribution in the beam junction region

    International Nuclear Information System (INIS)

    Li, Qilin; Gu, Wendong; Mu, Jinming; Yin, Wenming; Gao, Min; Mo, Juncong; Pei, Honglei

    2015-01-01

    The purpose of this study was to investigate the role of beam collimator rotation in Volumetric Modulated Arc Therapy (VMAT) for craniospinal irradiation (CSI), and the impact on dose distribution in the beam junctions. Six adult patients were selected for the study. Six VMAT plans with different collimator angles were generated for each patient. The patients were treated in supine position with two beam isocenters. The plans were evaluated by analysis of Dose-Volume Histogram (DVHs) data for planning target volume (PTV) and organs at risk (OAR), and conformity index (CI) and homogeneity index (HI) for the target. Dose distributions in the beam junctions were examined carefully and experimentally validated in phantom, with measurement using an ion chamber array and film. The mean values of HI and CI for the plans with different beam collimator angles were not significantly different. The numbers of segments, monitor units (MUs) and the delivery time of the plans with 45° beam collimator were obviously higher than those in plans with other beam collimator angles. When collimator angle for both sets of beams were set at 0°, there was a 1 mm low dose gap measured in the junction region. By setting the collimator angle to 45°, only two isocenters were needed for the treatment of a target with the length up to 90 cm. The HI and CI of the plans were almost the same, regardless if the collimator angles were at 0°. The collimator angles for at least one set of beams should be off 0° in order to avoid a dose gap in the beam junction region. The online version of this article (doi:10.1186/s13014-015-0544-z) contains supplementary material, which is available to authorized users

  3. Verification techniques and dose distribution for computed tomographic planned supine craniospinal radiation therapy

    International Nuclear Information System (INIS)

    Chang, Eric L.; Wong Peifong; Forster, Kenneth M.; Petru, Mark D.; Kowalski, Alexander V.; Maor, Moshe H.

    2003-01-01

    A modified 3-field technique was designed with opposed cranial fields and a single spinal field encompassing the entire spinal axis. Two methods of plan verifications were performed before the first treatment. First, a system of orthogonal rulers plus the thermoplastic head holder was used to visualize the light fields at the craniospinal junction. Second, film phantom measurements were taken to visualize the gap between the fields at the level of the spinal cord. Treatment verification entailed use of a posterior-anterior (PA) portal film and placement of radiopaque wire on the inferior border of the cranial field. More rigorous verification required a custom-fabricated orthogonal film holder. The isocenter positions of both fields when they matched were recorded using a record-and-verify system. A single extended distance spinal field collimated at 42 degree sign encompassed the entire spinal neuraxis. Data were collected from 40 fractions of craniospinal irradiation (CSI). The systematic error observed for the actual daily treatments was -0.5 mm (underlap), while the stochastic error was represented by a standard deviation of 5.39 mm. Measured data across the gapped craniospinal junction with junction shifts included revealed a dose ranging from 89.3% to 108%. CSI can be performed without direct visualization of the craniospinal junction by using the verification methods described. While the use of rigorous film verification for supine technique may have reduced the systematic error, the inability to visualize the supine craniospinal junction on skin appears to have increased the stochastic error compared to published data on such errors associated with prone craniospinal irradiation

  4. A Three-Isocenter Jagged-Junction IMRT Approach for Craniospinal Irradiation Without Beam Edge Matching for Field Junctions

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Fred, E-mail: fcao@bccancer.bc.ca [Department of Medical Physics, Fraser Valley Centre, BC Cancer Agency, Surrey, British Columbia (Canada); Ramaseshan, Ramani; Corns, Robert; Harrop, Sheryl [Department of Medical Physics, Fraser Valley Centre, BC Cancer Agency, Surrey, British Columbia (Canada); Nuraney, Nimet; Steiner, Peter; Aldridge, Stephanie [Department of Radiation Oncology, Fraser Valley Centre, BC Cancer Agency, Surrey, British Columbia (Canada); Liu, Mitchell; Carolan, Hannah [Department of Radiation Oncology, Vancouver Centre, BC Cancer Agency, Vancouver, British Columbia (Canada); Agranovich, Alex; Karvat, Anand [Department of Radiation Oncology, Fraser Valley Centre, BC Cancer Agency, Surrey, British Columbia (Canada)

    2012-11-01

    Purpose: Traditionally craniospinal irradiation treats the central nervous system using two or three adjacent field sets. We propose a technique using a three-isocenter intensity-modulated radiotherapy (IMRT) plan (jagged-junction IMRT) which overcomes problems associated with field junctions and beam edge matching and improves planning and treatment setup efficiencies with homogenous target dose distribution. Methods and Materials: Treatments for 3 patients with a prescription of 36 Gy in 20 fractions were retrospectively planned with jagged-junction IMRT and compared to conventional treatment plans. Planning target volume (PTV) included the whole brain and spinal canal to the S3 vertebral level. The plan used three field sets, each with a unique isocenter. One field set with seven fields treated the cranium. Two field sets treated the spine, each set using three fields. Fields from adjacent sets were overlapped, and the optimization process smoothly integrated the dose inside the overlapped junction. Results: For jagged-junction IMRT plans vs. conventional technique, the average homogeneity index equaled 0.08 {+-} 0.01 vs. 0.12 {+-} 0.02, respectively, and conformity number equaled 0.79 {+-} 0.01 vs. 0.47 {+-} 0.12, respectively. The 95% isodose surface covered (99.5 {+-} 0.3)% of the PTV vs. (98.1 {+-} 2.0)%, respectively. Both jagged-junction IMRT plans and the conventional plans had good sparing of organs at risk. Conclusions: Jagged-junction IMRT planning provided good dose homogeneity and conformity to the target while maintaining a low dose to organs at risk. Results from jagged-junction IMRT plans were better than or equivalent to those from the conventional technique. Jagged-junction IMRT optimization smoothly distributed dose in the junction between field sets. Because there was no beam matching, this treatment technique is less likely to produce hot or cold spots at the junction, in contrast to conventional techniques. The planning process is also

  5. A Three-Isocenter Jagged-Junction IMRT Approach for Craniospinal Irradiation Without Beam Edge Matching for Field Junctions

    International Nuclear Information System (INIS)

    Cao, Fred; Ramaseshan, Ramani; Corns, Robert; Harrop, Sheryl; Nuraney, Nimet; Steiner, Peter; Aldridge, Stephanie; Liu, Mitchell; Carolan, Hannah; Agranovich, Alex; Karvat, Anand

    2012-01-01

    Purpose: Traditionally craniospinal irradiation treats the central nervous system using two or three adjacent field sets. We propose a technique using a three-isocenter intensity-modulated radiotherapy (IMRT) plan (jagged-junction IMRT) which overcomes problems associated with field junctions and beam edge matching and improves planning and treatment setup efficiencies with homogenous target dose distribution. Methods and Materials: Treatments for 3 patients with a prescription of 36 Gy in 20 fractions were retrospectively planned with jagged-junction IMRT and compared to conventional treatment plans. Planning target volume (PTV) included the whole brain and spinal canal to the S3 vertebral level. The plan used three field sets, each with a unique isocenter. One field set with seven fields treated the cranium. Two field sets treated the spine, each set using three fields. Fields from adjacent sets were overlapped, and the optimization process smoothly integrated the dose inside the overlapped junction. Results: For jagged-junction IMRT plans vs. conventional technique, the average homogeneity index equaled 0.08 ± 0.01 vs. 0.12 ± 0.02, respectively, and conformity number equaled 0.79 ± 0.01 vs. 0.47 ± 0.12, respectively. The 95% isodose surface covered (99.5 ± 0.3)% of the PTV vs. (98.1 ± 2.0)%, respectively. Both jagged-junction IMRT plans and the conventional plans had good sparing of organs at risk. Conclusions: Jagged-junction IMRT planning provided good dose homogeneity and conformity to the target while maintaining a low dose to organs at risk. Results from jagged-junction IMRT plans were better than or equivalent to those from the conventional technique. Jagged-junction IMRT optimization smoothly distributed dose in the junction between field sets. Because there was no beam matching, this treatment technique is less likely to produce hot or cold spots at the junction, in contrast to conventional techniques. The planning process is also simplified as

  6. Critical Combinations of Radiation Dose and Volume Predict Intelligence Quotient and Academic Achievement Scores After Craniospinal Irradiation in Children With Medulloblastoma

    International Nuclear Information System (INIS)

    Merchant, Thomas E.; Schreiber, Jane E.; Wu, Shengjie; Lukose, Renin; Xiong, Xiaoping; Gajjar, Amar

    2014-01-01

    Purpose: To prospectively follow children treated with craniospinal irradiation to determine critical combinations of radiation dose and volume that would predict for cognitive effects. Methods and Materials: Between 1996 and 2003, 58 patients (median age 8.14 years, range 3.99-20.11 years) with medulloblastoma received risk-adapted craniospinal irradiation followed by dose-intense chemotherapy and were followed longitudinally with multiple cognitive evaluations (through 5 years after treatment) that included intelligence quotient (estimated intelligence quotient, full-scale, verbal, and performance) and academic achievement (math, reading, spelling) tests. Craniospinal irradiation consisted of 23.4 Gy for average-risk patients (nonmetastatic) and 36-39.6 Gy for high-risk patients (metastatic or residual disease >1.5 cm 2 ). The primary site was treated using conformal or intensity modulated radiation therapy using a 2-cm clinical target volume margin. The effect of clinical variables and radiation dose to different brain volumes were modeled to estimate cognitive scores after treatment. Results: A decline with time for all test scores was observed for the entire cohort. Sex, race, and cerebrospinal fluid shunt status had a significant impact on baseline scores. Age and mean radiation dose to specific brain volumes, including the temporal lobes and hippocampi, had a significant impact on longitudinal scores. Dichotomized dose distributions at 25 Gy, 35 Gy, 45 Gy, and 55 Gy were modeled to show the impact of the high-dose volume on longitudinal test scores. The 50% risk of a below-normal cognitive test score was calculated according to mean dose and dose intervals between 25 Gy and 55 Gy at 10-Gy increments according to brain volume and age. Conclusions: The ability to predict cognitive outcomes in children with medulloblastoma using dose-effects models for different brain subvolumes will improve treatment planning, guide intervention, and help estimate

  7. Critical Combinations of Radiation Dose and Volume Predict Intelligence Quotient and Academic Achievement Scores After Craniospinal Irradiation in Children With Medulloblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Merchant, Thomas E., E-mail: thomas.merchant@stjude.org [Division of Radiation Oncology, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Schreiber, Jane E. [Department of Psychology, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Wu, Shengjie [Department of Biostatistcs, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Lukose, Renin [Division of Radiation Oncology, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Xiong, Xiaoping [Department of Biostatistcs, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Gajjar, Amar [Department of Oncology, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States)

    2014-11-01

    Purpose: To prospectively follow children treated with craniospinal irradiation to determine critical combinations of radiation dose and volume that would predict for cognitive effects. Methods and Materials: Between 1996 and 2003, 58 patients (median age 8.14 years, range 3.99-20.11 years) with medulloblastoma received risk-adapted craniospinal irradiation followed by dose-intense chemotherapy and were followed longitudinally with multiple cognitive evaluations (through 5 years after treatment) that included intelligence quotient (estimated intelligence quotient, full-scale, verbal, and performance) and academic achievement (math, reading, spelling) tests. Craniospinal irradiation consisted of 23.4 Gy for average-risk patients (nonmetastatic) and 36-39.6 Gy for high-risk patients (metastatic or residual disease >1.5 cm{sup 2}). The primary site was treated using conformal or intensity modulated radiation therapy using a 2-cm clinical target volume margin. The effect of clinical variables and radiation dose to different brain volumes were modeled to estimate cognitive scores after treatment. Results: A decline with time for all test scores was observed for the entire cohort. Sex, race, and cerebrospinal fluid shunt status had a significant impact on baseline scores. Age and mean radiation dose to specific brain volumes, including the temporal lobes and hippocampi, had a significant impact on longitudinal scores. Dichotomized dose distributions at 25 Gy, 35 Gy, 45 Gy, and 55 Gy were modeled to show the impact of the high-dose volume on longitudinal test scores. The 50% risk of a below-normal cognitive test score was calculated according to mean dose and dose intervals between 25 Gy and 55 Gy at 10-Gy increments according to brain volume and age. Conclusions: The ability to predict cognitive outcomes in children with medulloblastoma using dose-effects models for different brain subvolumes will improve treatment planning, guide intervention, and help

  8. Nonparallel changes of growth hormone (GH) and insulin-like growth factor-I, insulin-like growth factor binding protein-3, and GH-binding protein, after craniospinal irradiation and chemotherapy

    International Nuclear Information System (INIS)

    Nivot, S.; Adan, L.; Souberbielle, J.; Rappaport, R.; Brauner, R.; Benelli, C.; Clot, J.P.; Saucet, C.; Zucker, J.M.

    1994-01-01

    The authors studied the GH-insulin-like growth factor-I (IGF-I) axis serially over 24-36 months in six patients with medulloblastoma who underwent surgical removal of the tumor followed by craniospinal irradiation therapy for 6 weeks and then chemotherapy for 42 weeks. Eighteen and 24 months after beginning irradiation there was a decline in the peak GH secretory response to acute stimulation with arginine/insulin hypoglycemia. Six months after irradiation and during chemotherapy there was a transient decline in IGF-I, IGF binding protein-3 (IGFBP-3), and GH-BP values (respective mean values of 56.1 ± 9.0 ng/mL, 1.1 ± 0.2 μg/mL, and 7.6 ± 3.3% of radioactivity as compared to time 0 values: 139 ± 15 ng/mL, 2.2 ± 0.2 μg/mL, and 20.0 ± 4.0%, P < 0.001), although provoked GH secretion was normal at this time. The IGF-I, IGFBP-3, and GH-BP returned to pretreatment ranges by 12-36 months after initiation of the study. There was also a decline in body mass index and serum protein values at 6 months after irradiation in ligand and immunoblot analysis there was a decline in IGFBP-3 and an abnormal electrophoretic mobility of IGFBP-2 that were both normalized at 36 months. In one patient they observed a high level of IGFBP-3 proteolysis at this time. This study demonstrates that before the decrease of GH secretion in patients receiving cranial irradiation there is a transient phase of GH insensitivity that may be characteristic of the acute therapeutic phase including the chemotherapy. This partial insensitivity may explain the early growth retardation observed in these patients. 28 refs., 4 figs., 1 tab

  9. Multi-Institution Prospective Trial of Reduced-Dose Craniospinal Irradiation (23.4 Gy) Followed by Conformal Posterior Fossa (36 Gy) and Primary Site Irradiation (55.8 Gy) and Dose-Intensive Chemotherapy for Average-Risk Medulloblastoma

    International Nuclear Information System (INIS)

    Merchant, Thomas E.; Kun, Larry E.; Krasin, Matthew J.; Wallace, Dana; Chintagumpala, Murali M.; Woo, Shiao Y.; Ashley, David M.; Sexton, Maree; Kellie, Stewart J.; Ahern, Verity M.B.B.S.; Gajjar, Amar

    2008-01-01

    Purpose: Limiting the neurocognitive sequelae of radiotherapy (RT) has been an objective in the treatment of medulloblastoma. Conformal RT to less than the entire posterior fossa (PF) after craniospinal irradiation might reduce neurocognitive sequelae and requires evaluation. Methods and Materials: Between October 1996 and August 2003, 86 patients, 3-21 years of age, with newly diagnosed, average-risk medulloblastoma were treated in a prospective, institutional review board-approved, multi-institution trial of risk-adapted RT and dose-intensive chemotherapy. RT began within 28 days of definitive surgery and consisted of craniospinal irradiation (23.4 Gy), conformal PF RT (36.0 Gy), and primary site RT (55.8 Gy). The planning target volume for the primary site included the postoperative tumor bed surrounded by an anatomically confined margin of 2 cm that was then expanded with a geometric margin of 0.3-0.5 cm. Chemotherapy was initiated 6 weeks after RT and included four cycles of high-dose cyclophosphamide, cisplatin, and vincristine. Results: At a median follow-up of 61.2 months (range, 5.2-115.0 months), the estimated 5-year event-free survival and cumulative incidence of PF failure rate was 83.0% ± 5.3% and 4.9% ± 2.4% (± standard error), respectively. The targeting guidelines used in this study resulted in a mean reduction of 13% in the volume of the PF receiving doses >55 Gy compared with conventionally planned RT. The reductions in the dose to the temporal lobes, cochleae, and hypothalamus were statistically significant. Conclusion: This prospective trial has demonstrated that irradiation of less than the entire PF after 23.4 Gy craniospinal irradiation for average-risk medulloblastoma results in disease control comparable to that after treatment of the entire PF

  10. Anti-emetic effect of granisetron in patients undergoing cranial and craniospinal radiotherapy

    International Nuclear Information System (INIS)

    Yamasaki, Fumiyuki; Watanabe, Yosuke; Nosaka, Ryo

    2014-01-01

    Approximately 30-59% of patients undergoing cranial or craniospinal radiotherapy experience nausea and/or vomiting. Here, we evaluated the effectiveness of granisetron for controlling emesis in patients treated with cranial or craniospinal radiotherapy. Between December 2011 and January 2013, 34 patients (19 males, 15 females; age range, 3-80 years) received cranial or craniospinal radiotherapy at our department. All but one male patient, who developed meningitis during the irradiation period were enrolled in this retrospective study. Patients who experienced irradiation-induced vomiting (grade 1) or nausea (grade 2) were treated with granisetron as a rescue anti-emetic. Episodes were graded as no vomiting, no nausea, no anti-emetic; no vomiting, nausea, no anti-emetic; no vomiting, nausea with anti-emetic; and vomiting. Of the 9 patients who underwent whole-brain or whole neural-axis irradiation, 5 (55.6%) experienced grade 2 nausea or vomiting. Two of 6 patients (33.3%) treated with whole ventricle irradiation experienced grade 2 nausea or vomiting. Three of 18 patients (16.7%) who underwent local-field irradiation experienced grade 2 nausea or vomiting. Patients who underwent wide-field irradiation experienced nausea, vomiting, and anorexia (p<0.05). Complete response (no vomiting, no additional rescue anti-emetic, and no nausea) was observed in 5 of 9 patients treated with granisetron. Four of 9 patients (44.4%) treated with granisetron experienced constipation (grade 1 or 2); its administration had no major adverse effects in our study population. Rescue therapy with granisetron is safe and effective to treat nausea and vomiting in patients subjected to cranial or craniospinal irradiation. (author)

  11. Inter-Institutional Comparison of Personalized Risk Assessments for Second Malignant Neoplasms for a 13-Year-Old Girl Receiving Proton versus Photon Craniospinal Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Taddei, Phillip J., E-mail: pt06@aub.edu.lb [Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Unit 1202, 1515 Holcombe Blvd, Houston, TX 77030 (United States); The University of Texas Graduate School of Biomedical Sciences at Houston, P.O. Box 20334, Houston, TX 77225 (United States); Department of Radiation Oncology, American University of Beirut Medical Center, P.O. Box 11-0236, Riad El Solh, Beirut 1107 2020 (Lebanon); Khater, Nabil [Department of Radiation Oncology, Hôtel-Dieu de France Hospital, University of St. Joseph, P.O. Box 166830, Alfred Naccache Blvd, Beirut (Lebanon); Zhang, Rui [Medical Physics Program, Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Tower Dr., Baton Rouge, LA 70803 (United States); Department of Physics, Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, LA 70809 (United States); Geara, Fady B. [Department of Radiation Oncology, American University of Beirut Medical Center, P.O. Box 11-0236, Riad El Solh, Beirut 1107 2020 (Lebanon); Mahajan, Anita [Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Unit 1202, 1515 Holcombe Blvd, Houston, TX 77030 (United States); The University of Texas Graduate School of Biomedical Sciences at Houston, P.O. Box 20334, Houston, TX 77225 (United States); Jalbout, Wassim [Department of Radiation Oncology, American University of Beirut Medical Center, P.O. Box 11-0236, Riad El Solh, Beirut 1107 2020 (Lebanon); Pérez-Andújar, Angélica [Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Unit 1202, 1515 Holcombe Blvd, Houston, TX 77030 (United States); Youssef, Bassem [Department of Radiation Oncology, American University of Beirut Medical Center, P.O. Box 11-0236, Riad El Solh, Beirut 1107 2020 (Lebanon); Newhauser, Wayne D. [Medical Physics Program, Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Tower Dr., Baton Rouge, LA 70803 (United States); Department of Physics, Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, LA 70809 (United States)

    2015-03-10

    Children receiving radiotherapy face the probability of a subsequent malignant neoplasm (SMN). In some cases, the predicted SMN risk can be reduced by proton therapy. The purpose of this study was to apply the most comprehensive dose assessment methods to estimate the reduction in SMN risk after proton therapy vs. photon therapy for a 13-year-old girl requiring craniospinal irradiation (CSI). We reconstructed the equivalent dose throughout the patient’s body from therapeutic and stray radiation and applied SMN incidence and mortality risk models for each modality. Excluding skin cancer, the risk of incidence after proton CSI was a third of that of photon CSI. The predicted absolute SMN risks were high. For photon CSI, the SMN incidence rates greater than 10% were for thyroid, non-melanoma skin, lung, colon, stomach, and other solid cancers, and for proton CSI they were non-melanoma skin, lung, and other solid cancers. In each setting, lung cancer accounted for half the risk of mortality. In conclusion, the predicted SMN risk for a 13-year-old girl undergoing proton CSI was reduced vs. photon CSI. This study demonstrates the feasibility of inter-institutional whole-body dose and risk assessments and also serves as a model for including risk estimation in personalized cancer care.

  12. Craniospinal radiotherapy in adult medulloblastoma

    International Nuclear Information System (INIS)

    Selek, U.; Zorlu, F.; Hurmuz, P.; Cengiz, M.; Gurkaynak, M.; Turker, A.; Soylemezoglu, F.

    2007-01-01

    Purpose: To evaluate the outcome and prognostic factors of adult patients with medulloblastoma. Patients and Methods: 26 adult medulloblastoma patients with a median age of 27 were subjected to craniospinal radiotherapy. A dose of 30.6 Gy with 1.8 Gy/fraction/day was prescribed to M0 patients, while 36 Gy were to be applied in patients with positive cerebrospinal liquor findings. The posterior fossa was boosted to 54 Gy. While 20 patients underwent external-beam radiotherapy alone, only six received sequential adjuvant chemotherapy. Results: Male/female ratio was 1.2. Preradiotherapy Karnofsky performance status was recorded as median 100%. 50% were classified as poor risk (n = 10, subtotal resection; n = 3, M+). The median follow-up time was 46.5 months. The 5-year actuarial survival rates for recurrence-free, distant metastasis-free, disease-free, and overall survival were 82.5%, 90.8%, 73.5%, and 89.7%, respectively. Patient characteristics, treatment factors and tumor characteristics failed to show any significance in univariate analysis. Grade 3 or 4 late morbidities were not observed. Conclusion: Yet, the current standard of care seems to remain craniospinal irradiation after maximal surgical resection of the primary neoplasm without clear indications for adjuvant chemotherapy. (orig.)

  13. SU-F-T-429: Craniospinal Irradiation by VMAT Technique: Impact of FFF Beam and High Resolution MLC On Plan Quality

    Energy Technology Data Exchange (ETDEWEB)

    Ganesh, T; Sarkar, B; Munshi, A; Mohanti, B [Fortis Memorial Research Institute, Gurgaon, Haryana (India)

    2016-06-15

    Purpose: Objective of this study was to evaluate the impact of using flattening filter free (FFF) beam with 0.5 cm multileaf collimator (MLC) leaves over conventional flattened beam with 1 cm leaf width MLC on the treatment plan quality in cranio-spinal irradiation (CSI). Methods: For five medulloblastoma cases (3 males and 2 females), who were previously treated by volumetric modulated arc therapy (VMAT) technique using conventional flattened beam shaped by 1 cm width MLC leaves, four test plans were generated and compared against the delivered plan. These retrospective plans consisted of four different combinations of flattened and FFF beams from Elekta’s Agility treatment head with 0.5 cm width MLC leaves. Sparing of organs at risks (OAR) in terms of dose to 5%, 50%, 75% and 90% volumes, mean and maximum dose were evaluated. Results: All plans satisfied the planning objective of covering 95% of PTV by at least 95% of prescription dose. Marginal variation of dose spillage was observed between different VMAT plans at very low dose range (1–5 Gy). Variation in dose statistics for PTVs and OARs were within 1% or 1 Gy. Amongst the five plans, the plan with flattened beam with 1 cm MLC had the highest number of MUs, 2.13 times higher than the plan with Agility MLC with FFF beam that had the least number of MUs. No statistically significant difference (p≥0.05) was observed between the reference plan and the retrospectively generated plans in terms of PTV coverage, cold spot, hot spot and organ at risk doses. Conclusion: In the treatment of CSI cases by VMAT technique, FFF beams and/or finer width MLC did not exhibit advantage over the flattened beams or wider MLC in terms of plan quality except for reduction in MUs.

  14. A comparative study on the risks of radiogenic second cancers and cardiac mortality in a set of pediatric medulloblastoma patients treated with photon or proton craniospinal irradiation

    International Nuclear Information System (INIS)

    Zhang, Rui; Howell, Rebecca M.; Taddei, Phillip J.; Giebeler, Annelise; Mahajan, Anita; Newhauser, Wayne D.

    2014-01-01

    Purpose: To compare the risks of radiogenic second cancers and cardiac mortality in 17 pediatric medulloblastoma patients treated with passively scattered proton or field-in-field photon craniospinal irradiation (CSI). Material/methods: Standard of care photon or proton CSI treatment plans were created for all 17 patients in a commercial treatment planning system (TPS) (Eclipse version 8.9; Varian Medical Systems, Palo Alto, CA) and prescription dose was 23.4 or 23.4 Gy (RBE) to the age specific target volume at 1.8 Gy/fraction. The therapeutic doses from proton and photon CSI plans were estimated from TPS. Stray radiation doses were determined from Monte Carlo simulations for proton CSI and from measurements and TPS for photon CSI. The Biological Effects of Ionization Radiation VII report and a linear model based on childhood cancer survivor data were used for risk predictions of second cancer and cardiac mortality, respectively. Results: The ratios of lifetime attributable risk (RLARs) (proton/photon) ranged from 0.10 to 0.22 for second cancer incidence and ranged from 0.20 to 0.53 for second cancer mortality, respectively. The ratio of relative risk (RRR) (proton/photon) of cardiac mortality ranged from 0.12 to 0.24. The RLARs of both cancer incidence and mortality decreased with patient’s age at exposure (e), while the RRRs of cardiac mortality increased with e. Girls had a significantly higher RLAR of cancer mortality than boys. Conclusion: Passively scattered proton CSI provides superior predicted outcomes by conferring lower predicted risks of second cancer and cardiac mortality than field-in-field photon CSI for all medulloblastoma patients in a large clinically representative sample in the United States, but the magnitude of superiority depends strongly on the patients’ anatomical development status

  15. Ovarian function in survivors of childhood medulloblastoma: Impact of reduced dose craniospinal irradiation and high-dose chemotherapy with autologous stem cell rescue.

    Science.gov (United States)

    Balachandar, Sadana; Dunkel, Ira J; Khakoo, Yasmin; Wolden, Suzanne; Allen, Jeffrey; Sklar, Charles A

    2015-02-01

    Data on ovarian function (OvF) in medulloblastoma (MB) survivors is limited, with most studies describing outcomes in survivors treated with craniospinal irradiation (CSI) doses >24 Gy ± standard chemotherapy. The objective of the current study is to report on OvF: (i) across a range of CSI doses; and (ii) following high-dose chemotherapy with autologous stem cell rescue (ASCR). Retrospective review of female MB survivors who were diagnosed in childhood and followed at Memorial Sloan Kettering Cancer Center. Patients were divided into three groups: (i) CSI ≤24 Gy +/- standard chemotherapy; (ii) CSI ≥35 Gy +/- standard chemotherapy; and (iii) high-dose chemotherapy with ASCR +/- CSI. Primary ovarian dysfunction (POD) occurred in 2/17 subjects in group 1, 3/9 subjects in group 2 and 5/5 subjects in group 3 (P < 0.01). Normalization of function was noted in four subjects with POD. Persistent POD requiring hormone replacement (POF) was observed in 1/17 subjects in group 1, 2/9 in group 2, and 3/5 in group 3 (P = 0.02). Neither age at treatment nor type of standard chemotherapy correlated with risk of POD or POF. Both POD and POF appear to occur in a small proportion of patients who are treated with contemporary doses of CSI +/- standard chemotherapy. However, ovarian dysfunction requiring hormone replacement therapy is common following high-dose chemotherapy associated with ASCR. These findings will assist clinicians in counseling patients regarding fertility preservation and risk of impaired ovarian function/future fertility. Pediatr Blood Cancer 2015;62:317-321. © 2014 Wiley Periodicals, Inc. © 2014 Wiley Periodicals, Inc.

  16. Out-of-field doses from pediatric craniospinal irradiations using 3D-CRT, IMRT, helical tomotherapy and electron-based therapy

    Science.gov (United States)

    De Saint-Hubert, Marijke; Verellen, Dirk; Poels, Kenneth; Crijns, Wouter; Magliona, Federica; Depuydt, Tom; Vanhavere, Filip; Struelens, Lara

    2017-07-01

    Medulloblastoma treatment involves irradiation of the entire central nervous system, i.e. craniospinal irradiation (CSI). This is associated with the significant exposure of large volumes of healthy tissue and there is growing concern regarding treatment-associated side effects. The current study compares out-of-field organ doses in children receiving CSI through 3D-conformal radiotherapy (3D-CRT), intensity modulated radiotherapy (IMRT), helical tomotherapy (HT) and an electron-based technique, and includes radiation doses resulting from imaging performed during treatment. An extensive phantom study is performed, using an anthropomorphic phantom corresponding to a five year old child, in which organ absorbed doses are measured using thermoluminescent detectors. Additionally, the study evaluates and explores tools for calculating out-of-field patient doses using the treatment planning system (TPS) and analytical models. In our study, 3D-CRT resulted in very high doses to a limited number of organs, while it was able to spare organs such as the lungs and breast when compared to IMRT and HT. Both IMRT and HT spread the dose over more organs and were able to spare the heart, thyroid, bladder, uterus and testes when compared to 3D-CRT. The electron-based technique considerably decreased the out-of-field doses in deep-seated organs but could not avoid nearby out-of-field organs such as the lungs, ribs, adrenals, kidneys and uterus. The daily imaging dose is small compared to the treatment dose burden. The TPS error for out-of-field doses was most pronounced for organs further away from the target; nevertheless, no systematic underestimation was observed for any of the studied TPS systems. Finally, analytical modeling was most optimal for 3D-CRT although the number of organs that could be modeled was limited. To conclude, none of the techniques studied was capable of sparing all organs from out-of-field doses. Nevertheless, the electron-based technique showed the most

  17. Evaluating Intensity Modulated Proton Therapy Relative to Passive Scattering Proton Therapy for Increased Vertebral Column Sparing in Craniospinal Irradiation in Growing Pediatric Patients

    Energy Technology Data Exchange (ETDEWEB)

    Giantsoudi, Drosoula, E-mail: dgiantsoudi@mgh.harvard.edu; Seco, Joao; Eaton, Bree R.; Simeone, F. Joseph; Kooy, Hanne; Yock, Torunn I.; Tarbell, Nancy J.; DeLaney, Thomas F.; Adams, Judith; Paganetti, Harald; MacDonald, Shannon M.

    2017-05-01

    Purpose: At present, proton craniospinal irradiation (CSI) for growing children is delivered to the whole vertebral body (WVB) to avoid asymmetric growth. We aimed to demonstrate the feasibility and potential clinical benefit of delivering vertebral body sparing (VBS) versus WVB CSI with passively scattered (PS) and intensity modulated proton therapy (IMPT) in growing children treated for medulloblastoma. Methods and Materials: Five plans were generated for medulloblastoma patients, who had been previously treated with CSI PS proton radiation therapy: (1) single posteroanterior (PA) PS field covering the WVB (PS-PA-WVB); (2) single PA PS field that included only the thecal sac in the target volume (PS-PA-VBS); (3) single PA IMPT field covering the WVB (IMPT-PA-WVB); (4) single PA IMPT field, target volume including thecal sac only (IMPT-PA-VBS); and (5) 2 posterior-oblique (−35°, +35°) IMPT fields, with the target volume including the thecal sac only (IMPT2F-VBS). For all cases, 23.4 Gy (relative biologic effectiveness [RBE]) was prescribed to 95% of the spinal canal. The dose, linear energy transfer, and variable-RBE-weighted dose distributions were calculated for all plans using the tool for particle simulation, version 2, Monte Carlo system. Results: IMPT VBS techniques efficiently spared the anterior vertebral bodies (AVBs), even when accounting for potential higher variable RBE predicted by linear energy transfer distributions. Assuming an RBE of 1.1, the V10 Gy(RBE) decreased from 100% for the WVB techniques to 59.5% to 76.8% for the cervical, 29.9% to 34.6% for the thoracic, and 20.6% to 25.1% for the lumbar AVBs, and the V20 Gy(RBE) decreased from 99.0% to 17.8% to 20.0% for the cervical, 7.2% to 7.6% for the thoracic, and 4.0% to 4.6% for the lumbar AVBs when IMPT VBS techniques were applied. The corresponding percentages for the PS VBS technique were higher. Conclusions: Advanced proton techniques can sufficiently reduce the dose to the vertebral

  18. Evaluating Intensity Modulated Proton Therapy Relative to Passive Scattering Proton Therapy for Increased Vertebral Column Sparing in Craniospinal Irradiation in Growing Pediatric Patients

    International Nuclear Information System (INIS)

    Giantsoudi, Drosoula; Seco, Joao; Eaton, Bree R.; Simeone, F. Joseph; Kooy, Hanne; Yock, Torunn I.; Tarbell, Nancy J.; DeLaney, Thomas F.; Adams, Judith; Paganetti, Harald; MacDonald, Shannon M.

    2017-01-01

    Purpose: At present, proton craniospinal irradiation (CSI) for growing children is delivered to the whole vertebral body (WVB) to avoid asymmetric growth. We aimed to demonstrate the feasibility and potential clinical benefit of delivering vertebral body sparing (VBS) versus WVB CSI with passively scattered (PS) and intensity modulated proton therapy (IMPT) in growing children treated for medulloblastoma. Methods and Materials: Five plans were generated for medulloblastoma patients, who had been previously treated with CSI PS proton radiation therapy: (1) single posteroanterior (PA) PS field covering the WVB (PS-PA-WVB); (2) single PA PS field that included only the thecal sac in the target volume (PS-PA-VBS); (3) single PA IMPT field covering the WVB (IMPT-PA-WVB); (4) single PA IMPT field, target volume including thecal sac only (IMPT-PA-VBS); and (5) 2 posterior-oblique (−35°, +35°) IMPT fields, with the target volume including the thecal sac only (IMPT2F-VBS). For all cases, 23.4 Gy (relative biologic effectiveness [RBE]) was prescribed to 95% of the spinal canal. The dose, linear energy transfer, and variable-RBE-weighted dose distributions were calculated for all plans using the tool for particle simulation, version 2, Monte Carlo system. Results: IMPT VBS techniques efficiently spared the anterior vertebral bodies (AVBs), even when accounting for potential higher variable RBE predicted by linear energy transfer distributions. Assuming an RBE of 1.1, the V10 Gy(RBE) decreased from 100% for the WVB techniques to 59.5% to 76.8% for the cervical, 29.9% to 34.6% for the thoracic, and 20.6% to 25.1% for the lumbar AVBs, and the V20 Gy(RBE) decreased from 99.0% to 17.8% to 20.0% for the cervical, 7.2% to 7.6% for the thoracic, and 4.0% to 4.6% for the lumbar AVBs when IMPT VBS techniques were applied. The corresponding percentages for the PS VBS technique were higher. Conclusions: Advanced proton techniques can sufficiently reduce the dose to the vertebral

  19. A prospective neurocognitive evaluation of children treated with additional chemotherapy and craniospinal irradiation following isolated central nervous system relapse in acute lymphoblastic leukemia

    International Nuclear Information System (INIS)

    Kumar, Parvesh; Mulhern, Raymond K.; Regine, William F.; Rivera, Gaston K.; Kun, Larry E.

    1995-01-01

    Purpose: A prospective assessment of neurocognitive performance was conducted in children with acute lymphoblastic leukemia (ALL) following isolated central nervous system (CNS) relapse to evaluate the impact of additional systemic/intrathecal (IT) chemotherapy and craniospinal irradiation (CSI) upon long-term intellectual function. Methods and Materials: Twenty-one children with ALL manifesting an isolated CNS relapse between 1984 through 1989 underwent serial evaluations of intellectual function. Neurocognitive function was measured by the full-scale intelligence quotient (FSIQ) as determined by the age-appropriate Wechsler Intelligence Scale and by achievement in reading, math, and spelling as assessed by the Wide Range Achievement Test (WRAT). Intelligence testing was initiated following isolated CNS relapse after clearance of cerebrospinal fluid (CSF) cytology but prior to CSI and continued at annual intervals for a minimum of 4 years postmeningeal failure. Protocol treatment for isolated CNS relapse consisted of reinduction and maintenance systemic therapy, intrathecal (IT) triple-agent chemotherapy, and early CSI (cranium to 24 Gy and spine to 15 Gy at 1.5 Gy/fraction) as outlined on the institutional 'Total XI' trial. Results: All 21 children attained secondary CNS remission and underwent the planned additional systemic/IT chemotherapy and CSI. Fourteen of the 21 children remain in secondary continuous remission, while the remaining 7 experienced a second relapse and were removed from further neurocognitive assessment. For the eight female and six male long-term survivors, mean ages at original diagnosis and at CSI were 5.7 years (range = 0.6-16.2) and 7.0 years (range = 1.8-17.0), respectively. At a median follow-up interval of 4.6 years (ranges 1.7-6.8) post-CNS relapse, comparison of group mean initial to final FSIQs revealed no statistically significant difference between the two measures (94.5 vs. 95.9, respectively, n = 11, p = 0.52). None of the

  20. Acute toxicity and treatment interruption related to electron and photon craniospinal irradiation in pediatric patients treated at the University of Texas M. D. Anderson Cancer Center

    International Nuclear Information System (INIS)

    Chang, Eric L.; Allen, Pamela; Wu, Catherine; Ater, Joann; Kuttesch, John; Maor, Moshe H.

    2002-01-01

    Purpose: To determine the incidence of acute toxicity and treatment interruption associated with electron and photon craniospinal irradiation (CSI) in children treated with or without chemotherapy. Methods and Materials: A retrospective study involving a computerized search of the radiotherapy database at the University of Texas M. D. Anderson Cancer Center identified a total of 79 eligible patients ≤18 years old who had received electron (n=46) or photon (n=33) CSI from October 1980 to March 2000. Acute toxicity was graded according to the 1998 National Cancer Institute Common Toxicity Criteria. Chemotherapy sequencing was categorized as before or after CSI or no chemotherapy. The incidences of weight loss and skin toxicity were recorded and differences in treatment interruption and hematologic values with respect to modality used (electron vs. photon), age (≤6 or >6 years), and sequencing of chemotherapy were compared using chi-square tests. Results: The median age of the electron group was lower than that of the photon group (6.7 years and 11.7 years, respectively). The two groups were otherwise well matched in terms of median spinal dose (31.1 vs. 33.3 Gy), fraction size (1.57 vs. 1.63 Gy), and total treatment time (32.4 vs. 30.7 days). Only 2 patients in each group (photon and electron) had a treatment break (>3 days). The mean number of days interrupted was 0.94 (photon) and 1.1 (electron) (p=0.72). The electron and photon groups were well balanced in terms of receiving pre-CSI chemotherapy (37% vs. 41%, p=0.776). Chemotherapy given before radiotherapy vs. after or not at all was associated with an increased incidence of Grade 3-4 leukopenia (76% vs. 49%, p=0.02), thrombocytopenia (90% vs. 10%, p=0), and neutropenia (50% vs. 15%, p=0.005). A younger age was associated with Grade 3-4 thrombocytopenia (29% vs. 8.7%, p=0.034), and decreased hemoglobin (29% vs. 6.5%, p=0.014). The incidence of leukocyte depression of Grade 3-4 toxicity was 62% in the electron

  1. SU-E-T-229: Craniospinal Radiotherapy Planning with VMAT, Two First Years Experience

    Energy Technology Data Exchange (ETDEWEB)

    Lliso, F; Carmona, V; Gimeno, J; Candela-Juan, C; Bautista, J [La Fe University and Polytechnic Hospital, Valencia, Valencia (Spain); Richart, J [ITIC, Hospital Clinica Benidorm, Benidorm, Alicante (Spain); Perez-Calatayud, J [La Fe University and Polytechnic Hospital, Valencia, Valencia (Spain); ITIC, Hospital Clinica Benidorm, Benidorm, Alicante (Spain)

    2015-06-15

    Purpose: To describe how we moved to VMAT in the craniospinal radiotherapy planning process, the actual procedure details, and the results for the patients treated. Methods: Twelve patients underwent craniospinal irradiation with the new procedure, based on the paper by Lee et al. (IJROBP 82, 2012), with some additional modifications. Patients were treated in supine position in Varian Clinac iX linacs with 6 MV RapidArc; prescription doses ranged from 23.4 to 40 Gy (13 to 20 fractions); depending on the PTV length, 2 or 3 isocenters were used, all coordinates being equal except the longitudinal one, setting a few centimeter-long overlapping region; 2 arcs (RA) sharing isocentre for the cranial region, RA1 encompassing cranium and superior spinal region, and RA2 intended to improve conformity, only for cranium; for spine, 1 or 2 isocenters were employed; optimization was performed with Eclipse (V 13.0) using AAA algorithm, establishing sets of optimization parameters to give high conformity while sparing OAR. In pediatric patients, homogeneous irradiation of the vertebrae was also required.Conformity (CI) and heterogeneity (HI) indices (same as Lee et al.), and mean and maximum doses for OAR were calculated. Several pre-treatment verification methods were used: Octavius4D (PTW) for each isocentre, point dose at the junction region, Portal Dosimetry (when possible), and independent MU verification software (Diamond, PTW). Results: CI median value was 1.02 (0.99–1.07) and HI, 1.07 (1.06–1.09); a great reduction was observed for CI and OAR mean doses with respect to Lee et al. data; median maximum eye lens dose was 7.3 Gy (4.0–12.0); mean LungV20Gy was 1.9%; in children, vertebrae were homogeneously irradiated (D95%=20.8 Gy, Dmean= 23.2 Gy).All pre-treatment verifications were found within our action levels except for Portal Dosimetry. Conclusion: A RapidArc planning process for craniospinal axis irradiation has been implemented with significant advantages on

  2. Standard and Nonstandard Craniospinal Radiotherapy Using Helical TomoTherapy

    International Nuclear Information System (INIS)

    Parker, William; Brodeur, Marylene; Roberge, David; Freeman, Carolyn

    2010-01-01

    Purpose: To show the advantages of planning and delivering craniospinal radiotherapy with helical TomoTherapy (TomoTherapy Inc., Madison, WI) by presenting 4 cases treated at our institution. Methods and Materials: We first present a standard case of craniospinal irradiation in a patient with recurrent myxopapillary ependymoma (MPE) and follow this with 2 cases requiring differential dosing to multiple target volumes. One of these, a patient with recurrent medulloblastoma, required a lower dose to be delivered to the posterior fossa because the patient had been previously irradiated to the full dose, and the other required concurrent boosts to leptomeningeal metastases as part of his treatment for newly diagnosed MPE. The final case presented is a patient with pronounced scoliosis who required spinal irradiation for recurrent MPE. Results: The four cases presented were planned and treated successfully with Helical Tomotherapy. Conclusions: Helical TomoTherapy delivers continuous arc-based intensity-modulated radiotherapy that gives high conformality and excellent dose homogeneity for the target volumes. Increased healthy tissue sparing is achieved at higher doses albeit at the expense of larger volumes of tissue receiving lower doses. Helical TomoTherapy allows for differential dosing of multiple targets, resulting in very elegant dose distributions. Daily megavoltage computed tomography imaging allows for precision of patient positioning, permitting a reduction in planning margins and increased healthy tissue sparing in comparison with standard techniques.

  3. Irradiation effects on c-axis lattice parameter in EuBa{sub 2}Cu{sub 3}O{sub y} irradiated with energetic ions

    Energy Technology Data Exchange (ETDEWEB)

    Ishikawa, Norito; Chimi, Yasuhiro; Iwase, Akihiro; Maeta, Hiroshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Tsuru, Koji; Michikami, Osamu

    1997-03-01

    We report an irradiation effect on c-axis lattice parameter in EuBa{sub 2}Cu{sub 3}O{sub y} oxide superconductors when irradiated with ions of energy ranging from 0.85 to 200 MeV. For the irradiation with low energy (0.85-2 MeV) ions, the defect production and the resultant c-axis lattice expansion were dominated by elastic collisions. On the other hand, for the irradiation with high energy (120-200 MeV) ions, the change in the c-axis lattice parameter was found to be much greater than that expected from the elastic displacement of target atoms. For high energy ion irradiation we could observe the excessive increase of c-axis lattice parameter reflecting additional production of defects which can be attributed to the electronic excitation. The large increase in c-axis lattice parameter due to high energy ion irradiation should be taken into account for the study on the interaction between vortices and irradiation-induced defects. (author)

  4. Cobalt-60 total body irradiation dosimetry at 220 cm source-axis distance

    International Nuclear Information System (INIS)

    Glasgow, G.P.; Mill, W.B.

    1980-01-01

    Adults with acute leukemia are treated with cyclophosphamide and total body irradiation (TBI) followed by autologous marrow transplants. For TBI, patients seated in a stand angled 45 0 above the floor are treated for about 2 hours at 220 cm source-axis distance (SAD) with sequential right and left lateral 87 cm x 87 cm fields to a 900 rad mid-pelvic dose at about 8 rad/min using a 5000 Ci cobalt unit. Maximum (lateral) to minimum (mid-plane) dose ratios are: hips--1.15, shoulders--1.30, and head--1.05, which is shielded by a compensator filter. Organ doses are small intestine, liver and kidneys--1100 rad, lung--1100 to 1200 rad, and heart--1300 rad. Verification dosimetry reveals the prescribed dose is delivered to within +-5%. Details of the dosimetry of this treatment are presented

  5. Alleviating action of OK-432 (Picibanil) on the myelosuppression in medulloblastoma patients induced by whole axis irradiation

    International Nuclear Information System (INIS)

    Aoki, Yoshiro

    1982-01-01

    The test subjects termed as OK-432 group which consist of 4 patients of Medulloblastoma and 2 of Pinealoma, underwent the whole axis irradiation in combination with OK-432. The control group consisting of 9 Medulloblastoma patients was subjected to the same radiation treatment without OK-432. Six of the nine patients (66.7%) irradiated showed the decrease of peripheral white blood cell counts down to 2,500, whereas, only two of six patients showed a similar decrement in OK-432 group. Three of the nine patients (33.3%) in the control group showed the decrease of white blood cell down to 2,000, but only one of the six patients in OK-432 group. The neutrophil counts decreased below the level of 1,000 in three of the nine patients (33.3%) in the control group, but none in the OK-432 group. The platelet counts decreased below the level of 100,000 in five of the nine patients (55.6%) in the control group during the irradiation period, but only one patient in the OK-432 group showed a decrease down to 100,000 counts. Three of the nine patients (33.3%) in the control group had to be stopped irradiation due to the severe leukopenia and thrombocytopenia, in contrast to the OK-432 group, which completed whole axis irradiation without interruption. These results seem to indicate that OK-432 alleviated the myelosuppression induced in patients by whole axis irradiation. This alleviating action of OK-432 is considered to be applicable to the treatment of Medulloblastoma patients. (J.P.N.)

  6. Comprehensive Craniospinal Radiation for Controlling Central Nervous System Leukemia

    International Nuclear Information System (INIS)

    Walker, Gary V.; Shihadeh, Ferial; Kantarjian, Hagop; Allen, Pamela; Rondon, Gabriela; Kebriaei, Partow; O'Brien, Susan; Kedir, Aziza; Said, Mustefa; Grant, Jonathan D.; Thomas, Deborah A.; Gidley, Paul W.; Arzu, Isidora; Pinnix, Chelsea; Reed, Valerie; Dabaja, Bouthaina S.

    2014-01-01

    Purpose: To determine the benefit of radiation therapy (RT) in resolution of neurologic symptoms and deficits and whether the type of RT fields influences central nervous system (CNS) control in adults with CNS leukemia. Methods and Materials: A total of 163 adults from 1996 to 2012 were retrospectively analyzed. Potential associations between use of radiation and outcome were investigated by univariate and multivariate analysis. Results: The median survival time was 3.8 months after RT. Common presenting symptoms were headache in 79 patients (49%), cranial nerve VII deficit in 46 (28%), and cranial nerve II deficit in 44 (27%). RT was delivered to the base of skull in 48 patients (29%), to the whole brain (WB) in 67 (41%), and to the craniospinal axis (CS) in 48 (29%). Among 149 patients with a total of 233 deficits, resolution was observed in 34 deficits (15%), improvement in 126 deficits (54%), stability in 34 deficits (15%), and progression in 39 deficits (17%). The 12-month CNS progression-free survival was 77% among those receiving CS/WB and 51% among those receiving base of skull RT (P=.02). On multivariate analysis, patients who did not undergo stem cell transplantation after RT and base of skull RT were associated with worse CNS progression-free survival. Conclusions: Improvement or resolution of symptoms occurred in two thirds of deficits after RT. Comprehensive radiation to the WB or CS seems to offer a better outcome, especially in isolated CNS involvement

  7. Comprehensive Craniospinal Radiation for Controlling Central Nervous System Leukemia

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Gary V.; Shihadeh, Ferial [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Kantarjian, Hagop [Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Allen, Pamela [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Rondon, Gabriela; Kebriaei, Partow [Department of Stem Cell Transplantation, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); O' Brien, Susan [Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Kedir, Aziza; Said, Mustefa; Grant, Jonathan D. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Thomas, Deborah A. [Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Gidley, Paul W. [Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Arzu, Isidora; Pinnix, Chelsea; Reed, Valerie [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Dabaja, Bouthaina S., E-mail: bdabaja@mdanderson.org [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2014-12-01

    Purpose: To determine the benefit of radiation therapy (RT) in resolution of neurologic symptoms and deficits and whether the type of RT fields influences central nervous system (CNS) control in adults with CNS leukemia. Methods and Materials: A total of 163 adults from 1996 to 2012 were retrospectively analyzed. Potential associations between use of radiation and outcome were investigated by univariate and multivariate analysis. Results: The median survival time was 3.8 months after RT. Common presenting symptoms were headache in 79 patients (49%), cranial nerve VII deficit in 46 (28%), and cranial nerve II deficit in 44 (27%). RT was delivered to the base of skull in 48 patients (29%), to the whole brain (WB) in 67 (41%), and to the craniospinal axis (CS) in 48 (29%). Among 149 patients with a total of 233 deficits, resolution was observed in 34 deficits (15%), improvement in 126 deficits (54%), stability in 34 deficits (15%), and progression in 39 deficits (17%). The 12-month CNS progression-free survival was 77% among those receiving CS/WB and 51% among those receiving base of skull RT (P=.02). On multivariate analysis, patients who did not undergo stem cell transplantation after RT and base of skull RT were associated with worse CNS progression-free survival. Conclusions: Improvement or resolution of symptoms occurred in two thirds of deficits after RT. Comprehensive radiation to the WB or CS seems to offer a better outcome, especially in isolated CNS involvement.

  8. Hypothyroidism in children with medulloblastoma: a comparison of 3600 and 2340 cGy craniospinal radiotherapy

    International Nuclear Information System (INIS)

    Paulino, Arnold C.

    2002-01-01

    Purpose: To determine if low-dose craniospinal irradiation (2340 cGy) with chemotherapy is associated with a lower incidence of hypothyroidism compared to standard dose (3600 cGy) with or without chemotherapy in children with medulloblastoma. Patients and Methods: Between 1980 and 1999, 32 patients ≤20 years old survived after craniospinal irradiation with or without chemotherapy. Twenty patients received 3600 cGy craniospinal irradiation (CSI), whereas 12 had 2340 cGy CSI; all patients received a posterior fossa boost to a total dose 5040-5580 cGy. The median ages at the time of CSI for those receiving 2340 cGy and 3600 cGy were 7.2 and 10.2 years, respectively. Chemotherapy (CT) was employed in 22 children. All children who received 2340 cGy had CT consisting of vincristine, CCNU, and either cisplatin or cyclophosphamide. Ten of 20 (50%) patients receiving 3600 cGy had CT; the most common regimen was vincristine, CCNU, and prednisone. Serum-free thyroxine and thyroid-stimulating hormone concentrations were measured in all children at variable times after radiotherapy. Thyroid-stimulating hormone responses to i.v. thyrotrophin-releasing hormone were assessed in those suspected of having central hypothyroidism. Median follow-up for children receiving 2340 cGy was 5 years (range: 2-11.2 years), whereas for those receiving 3600 cGy, follow-up was 12.5 years (range: 2.4-20 years). Results: Eighteen patients (56%) developed hypothyroidism at a median time after radiotherapy of 41 months (range: 10 months to 18 years). Primary hypothyroidism was more common than central hypothyroidism (38% and 19%). All 7 children 10 years had hypothyroidism (p<0.001). Hypothyroidism was documented in 10 of 12 (83%) who had 2340 cGy + CT, 6 of 10 (60%) who had 3600 cGy + CT, and 2 of 10 (20%) who had 3600 cGy without CT (p<0.025). Conclusions: Current treatment regimens consisting of chemotherapy and 2340 cGy craniospinal irradiation followed by a posterior fossa boost for

  9. Low-dose prophylactic craniospinal radiotherapy for intracranial germinoma

    International Nuclear Information System (INIS)

    Schoenfeld, Gordon O.; Amdur, Robert J.; Schmalfuss, Ilona M.; Morris, Christopher G.; Keole, Sameer R.; Mendenhall, William M.; Marcus, Robert B.

    2006-01-01

    Purpose: To report outcomes of patients with localized intracranial germinoma treated with low-dose craniospinal irradiation (CSI) followed by a boost to the ventricular system and primary site. Methods and Materials: Thirty-one patients had pathologically confirmed intracranial germinoma and no spine metastases. Low-dose CSI was administered in 29 patients: usually 21 Gy of CSI, 9.0 Gy of ventricular boost, and a 19.5-Gy tumor boost, all at 1.5 Gy per fraction. Our neuroradiologist recorded three-dimensional tumor size on magnetic resonance images before, during, and after radiotherapy. Results: With a median follow-up of 7.0 years, 29 of 31 patients (94%) are disease free. One failure had nongerminomatous histology; the initial diagnosis was a sampling error. Of 3 patients who did not receive CSI, 1 died. No patient developed myelopathy, visual deficits, dementia, or skeletal growth problems. In locally controlled patients, tumor response according to magnetic resonance scan was nearly complete within 6 months after radiotherapy. Conclusions: Radiotherapy alone with low-dose prophylactic CSI cures almost all patients with localized intracranial germinoma. Complications are rare when the daily dose of radiotherapy is limited to 1.5 Gy and the total CSI dose to 21 Gy. Patients without a near-complete response to radiotherapy should undergo resection to rule out a nongerminomatous element

  10. Computed tomographic simulation of craniospinal fields in pediatric patients: improved treatment accuracy and patient comfort.

    Science.gov (United States)

    Mah, K; Danjoux, C E; Manship, S; Makhani, N; Cardoso, M; Sixel, K E

    1998-07-15

    To reduce the time required for planning and simulating craniospinal fields through the use of a computed tomography (CT) simulator and virtual simulation, and to improve the accuracy of field and shielding placement. A CT simulation planning technique was developed. Localization of critical anatomic features such as the eyes, cribriform plate region, and caudal extent of the thecal sac are enhanced by this technique. Over a 2-month period, nine consecutive pediatric patients were simulated and planned for craniospinal irradiation. Four patients underwent both conventional simulation and CT simulation. Five were planned using CT simulation only. The accuracy of CT simulation was assessed by comparing digitally reconstructed radiographs (DRRs) to portal films for all patients and to conventional simulation films as well in the first four patients. Time spent by patients in the CT simulation suite was 20 min on average and 40 min maximally for those who were noncompliant. Image acquisition time was absence of the patient, virtual simulation of all fields took 20 min. The DRRs were in agreement with portal and/or simulation films to within 5 mm in five of the eight cases. Discrepancies of > or =5 mm in the positioning of the inferior border of the cranial fields in the first three patients were due to a systematic error in CT scan acquisition and marker contouring which was corrected by modifying the technique after the fourth patient. In one patient, the facial shield had to be moved 0.75 cm inferiorly owing to an error in shield construction. Our analysis showed that CT simulation of craniospinal fields was accurate. It resulted in a significant reduction in the time the patient must be immobilized during the planning process. This technique can improve accuracy in field placement and shielding by using three-dimensional CT-aided localization of critical and target structures. Overall, it has improved staff efficiency and resource utilization.

  11. Computed tomographic simulation of craniospinal fields in pediatric patients: improved treatment accuracy and patient comfort

    International Nuclear Information System (INIS)

    Mah, Katherine; Danjoux, Cyril E.; Manship, Sharan; Makhani, Nadiya; Cardoso, Marlene; Sixel, Katharina E.

    1998-01-01

    Purpose: To reduce the time required for planning and simulating craniospinal fields through the use of a computed tomography (CT) simulator and virtual simulation, and to improve the accuracy of field and shielding placement. Methods and Materials: A CT simulation planning technique was developed. Localization of critical anatomic features such as the eyes, cribriform plate region, and caudal extent of the thecal sac are enhanced by this technique. Over a 2-month period, nine consecutive pediatric patients were simulated and planned for craniospinal irradiation. Four patients underwent both conventional simulation and CT simulation. Five were planned using CT simulation only. The accuracy of CT simulation was assessed by comparing digitally reconstructed radiographs (DRRs) to portal films for all patients and to conventional simulation films as well in the first four patients. Results: Time spent by patients in the CT simulation suite was 20 min on average and 40 min maximally for those who were noncompliant. Image acquisition time was <10 min in all cases. In the absence of the patient, virtual simulation of all fields took 20 min. The DRRs were in agreement with portal and/or simulation films to within 5 mm in five of the eight cases. Discrepancies of ≥5 mm in the positioning of the inferior border of the cranial fields in the first three patients were due to a systematic error in CT scan acquisition and marker contouring which was corrected by modifying the technique after the fourth patient. In one patient, the facial shield had to be moved 0.75 cm inferiorly owing to an error in shield construction. Conclusions: Our analysis showed that CT simulation of craniospinal fields was accurate. It resulted in a significant reduction in the time the patient must be immobilized during the planning process. This technique can improve accuracy in field placement and shielding by using three-dimensional CT-aided localization of critical and target structures. Overall

  12. Postoperative craniospinal radiotherapy of medulloblastoma in children and young adults

    Directory of Open Access Journals (Sweden)

    Golubičić Ivana V.

    2003-01-01

    Full Text Available PURPOSE The aim of this study was: 1. to evaluate treatment results of combined therapy (surgery, postoperative craniospinal radiotherapy with or without chemotherapy and 2. to assess factors affecting prognosis (extend of tumor removal, involvement of the brain stem, extent of disease postoperative meningitis, shunt placement, age, sex and time interval from surgery to start of postoperative radiotherapy. PATIENTS AND METHODS During the period 1986-1996, 78 patients with medulloblastoma, aged 1-22 years (median 8.6 years, were treated with combined modality therapy and 72 of them were evaluable for the study end-points. Entry criteria were histologically proven diagnosis, age under 22 years, and no history of previous malignant disease. The main characteristics of the group are shown in Table 1. Twenty-nine patients (37.2% have total, 8 (10.3% near total and 41 (52.5% partial removal. Seventy-two of 78 patients were treated with curative intent and received postoperative craniospinal irradiation. Radiotherapy started 13-285 days after surgery (median 36 days. Only 13 patients started radiotherapy after 60 days following surgery. Adjuvant chemotherapy was applied in 63 (80.7% patients. The majority of them (46 73% received chemotherapy with CCNU and Vincristine. The survival rates were calculated with the Kaplan-Meier method and the differences in survival were analyzed using the Wilcoxon test and log-rank test. RESULTS The follow-up period ranged from 1-12 years (median 3 years. Five-year overall survival (OS was 51% and disease-free survival (DFS 47% (Graph 1. During follow-up 32 relapses occurred. Patients having no brain stem infiltration had significantly better survival (p=0.0023 (Graph 2. Patients with positive myelographic findings had significantly poorer survival compared to dose with negative myelographic findings (p=0.0116. Significantly poorer survival was found in patients with meningitis developing in the postoperative period

  13. Radiation doses to normal tissues during craniospinal irradiation ...

    African Journals Online (AJOL)

    Mohamed Farouk Mostafa

    2011-10-15

    Oct 15, 2011 ... b Department of Radiology, Alexandria Faculty of Medicine, Alexandria University, Alexandria, Egypt. Available online ... For the cranial fields, parallel opposed fields were used with the isocenter of the fields in the mid- plan in the .... the lateral brain ports and the posterior spine port to meet at the cervical ...

  14. Radiation doses to normal tissues during craniospinal irradiation ...

    African Journals Online (AJOL)

    Objective: This dosimetric study is aiming to report the results of the analysis of doses received by target volumes and organs outside the target volumes during the treatment of medulloblastoma patients. And also by comparing the doses reaching the eyes and the lens with the use of different shielding methods.

  15. Nuclear EGFR-PKM2 axis induces cancer stem cell-like characteristics in irradiation-resistant cells.

    Science.gov (United States)

    Shi, Ying; Liu, Na; Lai, Weiwei; Yan, Bin; Chen, Ling; Liu, Shouping; Liu, Shuang; Wang, Xiang; Xiao, Desheng; Liu, Xiaoli; Mao, Chao; Jiang, Yiqun; Jia, Jiantao; Liu, Yating; Yang, Rui; Cao, Ya; Tao, Yongguang

    2018-05-28

    Radiation therapy has become an important tool in the treatment of cancer patients, but most patients relapse within 5 years. Relapse is due to the presence of cancer stem cells (CSCs), but the molecular mechanism of radioresistance in CSCs remains largely elusive. Here, we found that irradiation-resistant (IR) cells exhibited increased stem cell-like properties together with elevated anchorage-independent growth and metastasis ability. EGFR not only leads to increased acquisition of endometrial cancer stem cell markers in radioresistant sublines but is critical for the cancer stem-cell phenotype and tumorigenicity. Moreover, PKM2 functions as an interacting partner of EGFR, which induces the EMT phenotype and stem cell-like properties in IR cells. Finally, we found that the regulatory function of the EGFR-PKM2 axis is dependent on nuclear EGFR. In sum, our study indicated that EGFR and PKM2 directly interact and bind with each other to regulate the transcription of stemness-related genes and promote the stem-like phenotype, thus promoting invasion and metastasis. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. Effects of central-nervous-system irradiation on neuropsychologic functioning of children with acute lymphocytic leukemia

    International Nuclear Information System (INIS)

    Soni, S.S.; Marten, G.W.; Pitner, S.E.; Duenas, D.A.; Powazek, M.

    1975-01-01

    Two neuropsychologic studies were performed to determine the long-term effects of ''prophylactic'' cranial or craniospinal irradiation on the psychologic and neurologic functions of children with acute lymphocytic leukemia. In a prospective study, 34 patients with leukemia who received either craniospinal irradiation or cranial irradiation combined with intrathecal methotrexate were evaluated by standardized neurologic and psychologic examinations before and after irradiation. Their performance was compared with that of 27 controls who received irradiation to parts of the body other than the cranium. In a retrospective study, 11 patients with leukemia receiving prophylactic craniospinal irradiation and 12 controls with the disease not receiving such therapy were followed from the second year after either irradiation or the initial hematologic remission. Eighteen months after irradiation in the prospective study and four years after irradiation in the retrospective study, no noteworthy neurologic or psychologic differences were found between subjects and controls

  17. Supine proton beam craniospinal radiotherapy using a novel tabletop adapter

    Energy Technology Data Exchange (ETDEWEB)

    Buchsbaum, Jeffrey C., E-mail: jbuchsba@iupui.edu [IU Health Proton Therapy Center, Bloomington, IN (United States); Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN (United States); Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN (United States); Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN (United States); Besemer, Abby; Simmons, Joseph; Hoene, Ted; Simoneaux, Victor; Sandefur, Amy [IU Health Proton Therapy Center, Bloomington, IN (United States); Wolanski, Mark; Li, Zhao; Cheng, Chee-Wei [IU Health Proton Therapy Center, Bloomington, IN (United States); Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN (United States)

    2013-04-01

    To develop a device that allows supine craniospinal proton and photon therapy to the vast majority of proton and photon facilities currently experiencing limitations as a result of couch design issues. Plywood and carbon fiber were used for the development of a prototype unit. Once this was found to be satisfactory after all design issues were addressed, computer-assisted design (CAD) was used and carbon fiber tables were built to our specifications at a local manufacturer of military and racing car carbon fiber parts. Clinic-driven design was done using real-time team discussion for a prototype design. A local machinist was able to construct a prototype unit for us in <2 weeks after the start of our project. Once the prototype had been used successfully for several months and all development issues were addressed, a custom carbon fiber design was developed in coordination with a carbon fiber manufacturer in partnership. CAD methods were used to design the units to allow oblique fields from head to thigh on patients up to 200 cm in height. Two custom-designed carbon fiber craniospinal tabletop designs now exist: one long and one short. Four are in successful use in our facility. Their weight tolerance is greater than that of our robot table joint (164 kg). The long unit allows for working with taller patients and can be converted into a short unit as needed. An affordable, practical means of doing supine craniospinal therapy with protons or photons can be used in most locations via the use of these devices. This is important because proton therapy provides a much lower integral dose than all other therapy methods for these patients and the supine position is easier for patients to tolerate and for anesthesia delivery. These units have been successfully used for adult and pediatric supine craniospinal therapy, proton therapy using oblique beams to the low pelvis, treatment of various spine tumors, and breast-sparing Hodgkin's therapy.

  18. Comparison and Analysis of Instruments Measuring Plane-of-Array Irradiance for One-Axis Tracking Systems: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Dooraghi, Michael R [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Sengupta, Manajit [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Vignola, Frank [University of Oregon; Chiu, Chun-Yun [University of Oregon; Peterson, Josh [University of Oregon

    2018-04-12

    A variety of sensors are studied on a one-axis tracking surface and a horizontal surface in Golden, Colorado, and Eugene, Oregon. This is the first year of a long-term study that will look at not only a comparison between the instruments but also the longer-term degradation in calibration and/or performance. Initially, results from each location will be analyzed, and then results will be compared and contrasted between the two locations. A quick comparison at Eugene indicates that reference solar cells seem to compare better against a secondary standard pyranometer on a one-axis tracker than photodiode-based pyranometers. More study is needed to characterize and confirm this finding.

  19. Thyroid dysfunction as a late effect in childhood medulloblastoma: a comparison of hyperfractionated versus conventionally fractionated craniospinal radiotherapy

    International Nuclear Information System (INIS)

    Ricardi, Umberto; Corrias, Andrea; Einaudi, Silvia; Genitori, Lorenzo; Sandri, Alessandro; Cordero Di Montezemolo, Luca; Besenzon, Luigi; Madon, Enrico; Urgesi, Alessandro

    2001-01-01

    Purpose: Primary hypothyroidism is a common sequela of craniospinal radiotherapy in the treatment of childhood medulloblastoma. Due to the strong radiobiologic rationale, hyperfractionation can reduce the delayed effects of radiation injury. Methods and Materials: The authors compared the incidence of thyroid dysfunction after conventionally fractionated radiotherapy (Group A, n=20 patients) vs. hyperfractionated radiotherapy (Group B, n=12 patients) in a group of pediatric patients with posterior fossa primitive neuroectodermal tumor (PNET). Results: The mean age at the time of tumor diagnosis was 7.4 years in Group A and 8.4 years in Group B. Thyroid function was evaluated yearly, with ultrasonographic examination every 2 years. The patients were followed after diagnosis for a mean of 10.8 years for Group A and 6.0 years for Group B. Approximately 80% of the Group A (16/20) and 33.3% of the Group B (4/12) patients developed primary hypothyroidism within a similar period after irradiation (4.2 vs. 3.5 years, respectively). Analysis by cumulative incidence function demonstrated a significant difference in the risk of developing thyroid dysfunction between these two groups of patients (p<0.05). Ultrasonography showed reduced thyroid volume in 7 Group A patients and structural changes in 21 patients (17 Group A, 4 Group B cases); a thyroid benign nodule was detected in 2 Group A patients. Conclusions: The current study findings suggest that the use of hyperfractionated craniospinal radiotherapy in the treatment of childhood medulloblastoma is associated with a lower risk of these patients' developing late thyroid dysfunction

  20. The growth of a c-axis highly oriented sandwiched TiO{sub 2} film with superhydrophilic properties without UV irradiation on SnO:F substrate

    Energy Technology Data Exchange (ETDEWEB)

    Han Yangang; Wu Gang; Wang Mang; Chen Hongzheng [Department of Polymer Science and Engineering, Key Laboratory of Macromolecule Synthesis and Functionalization of Ministry of Education, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027 (China)], E-mail: wmang@zju.edu.cn, E-mail: hzchen@zju.edu.cn

    2009-06-10

    A c-axis highly oriented sandwiched film composed of single-crystalline rutile TiO{sub 2} on SnO:F (FTO) substrate was fabricated by a simple hydrothermal technique. The sandwich structure of the TiO{sub 2} film was found to be constructed by two layers of TiO{sub 2} nanorods, which grew towards both directions of the bulk solution and the substrate, respectively. One TiO{sub 2} nanoparticle interlayer between them acted as the 'seed' layer. The length and the density of the TiO{sub 2} nanoarrays could be tuned by varying the experimental parameters such as temperature and time. The resultant TiO{sub 2} films showed a specific superhydrophilicity without any prior UV irradiation, which can be kept for a long period of time.

  1. Management Strategies and Outcomes for VHL-related Craniospinal Hemangioblastomas

    Directory of Open Access Journals (Sweden)

    Christ Ordookhanian

    2017-08-01

    Full Text Available Hemangioblastomas are rare and benign tumors accounting for less than 2% of all central nervous system (CNS tumors. The vast majority of hemangioblastomas occur sporadically, whereas a small number of cases, especially in younger patients, are associated with Von Hippel–Lindau (VHL syndrome. It is thought that loss of tumor suppressor function of the VHL gene results in stabilization of hypoxia-inducible factor alpha with downstream activation of cellular proliferative and angiogenic genes that promote tumorigenesis. VHL-related hemangioblastomas predominantly occur in the cerebellum and spine. Lesions are often diagnosed on contrast-enhanced craniospinal MRIs, and the diagnosis of VHL occurs through assessment for germline VHL mutations. Surgical resection remains the primary treatment modality for symptomatic or worrisome lesions, with excellent local control rates and neurological outcomes. Stereotactic radiotherapy can be employed in patients who are deemed high risk for surgery, have multiple lesions, or have non-resectable lesions. Given the tendency for development of either new or multiple lesions, close radiographic surveillance is often recommended for asymptomatic lesions.

  2. Large intradural craniospinal arachnoid cyst: A case report and review of literature

    Directory of Open Access Journals (Sweden)

    Souvagya Panigrahi

    2012-01-01

    Full Text Available Presence of an arachnoid cyst at craniospinal junction is not very common. This is a very rare anatomic site, with only seven other cases reported in the literature. We report a case of large intradural craniospinal arachnoid cyst presenting with obstructive hydrocephalus and cranial nerve palsy. A 39-year-old male presented with 8-month history of neck pain, headache, vomiting, visual disturbances, diminished taste sensation, and numbness of face. He had bilateral papilledema on ophthalmoscopy. Magnetic resonance imaging (MRI revealed a posterior fossa arachnoid cyst extending down to the lower border of C5 vertebra. Posterior decompression was done through C5 laminectomy. He made a full recovery and was asymptomatic at 6-month follow-up examination. The clinical features, diagnosis, and management of these rare craniospinal arachnoid cysts are discussed.

  3. The Role of the Craniocervical Junction in Craniospinal Hydrodynamics and Neurodegenerative Conditions

    Directory of Open Access Journals (Sweden)

    Michael F. Flanagan

    2015-01-01

    Full Text Available The craniocervical junction (CCJ is a potential choke point for craniospinal hydrodynamics and may play a causative or contributory role in the pathogenesis and progression of neurodegenerative diseases such as Alzheimer’s disease, Parkinson’s disease, MS, and ALS, as well as many other neurological conditions including hydrocephalus, idiopathic intracranial hypertension, migraines, seizures, silent-strokes, affective disorders, schizophrenia, and psychosis. The purpose of this paper is to provide an overview of the critical role of the CCJ in craniospinal hydrodynamics and to stimulate further research that may lead to new approaches for the prevention and treatment of the above neurodegenerative and neurological conditions.

  4. The Role of the Craniocervical Junction in Craniospinal Hydrodynamics and Neurodegenerative Conditions

    Science.gov (United States)

    Flanagan, Michael F.

    2015-01-01

    The craniocervical junction (CCJ) is a potential choke point for craniospinal hydrodynamics and may play a causative or contributory role in the pathogenesis and progression of neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, MS, and ALS, as well as many other neurological conditions including hydrocephalus, idiopathic intracranial hypertension, migraines, seizures, silent-strokes, affective disorders, schizophrenia, and psychosis. The purpose of this paper is to provide an overview of the critical role of the CCJ in craniospinal hydrodynamics and to stimulate further research that may lead to new approaches for the prevention and treatment of the above neurodegenerative and neurological conditions. PMID:26770824

  5. Craniospinal malformations in a twelve-year fetopathological study; the efficiency of ultrasonography in view of fetopathological investigations.

    Science.gov (United States)

    Joó, József Gábor; Beke, Artúr; Szigeti, Zsanett; Csaba, Akos; Mezei, Gábor; Tóth-Pál, Erno; Papp, Csaba

    2008-02-01

    Craniospinal malformations represent a heterogeneous group of congenital malformations by their morphology and etiology alike. Certain craniospinal malformations could be diagnosed as early as the dawn of ultrasonography and this group of malformations has been the focus of attention ever since. : The aim of the authors was to review the main characteristics of craniospinal malformations, as well as to evaluate the efficiency of ultrasonography based on autopsy examinations during twelve years. The current study comprises the details of 339 pregnancies terminated by induced abortion for craniospinal malformation between 1995 and 2006. Maternal median age was 27+/-5.8 years, ranging from 15 to 47 years. In 24.5% of the cases, there was a positive obsterical-gynecological or genetic history. In 68.1% of the cases, ultrasonographic and autopsy findings were completely identical; in 24.2% a partial coincidence was found, but autopsy allowed for further diagnoses, while in 26 cases (7.7%) different findings were obtained by prenatal ultrasonography and fetopathological investigations. In half of the latter 26 cases, induced abortion was suggested due to hydrocephalus confirmed by ultrasonography but not justified by autopsy or the autopsy revealed the presence of other craniospinal malformation(s). It can be concluded that - in view of the diagnostic efficiency of fetopathological investigations - the ultrasonographic diagnosis of hydrocephalus should be interpreted independently from other craniospinal malformations on the basis of principles of ultrasonographic methodology and at different times.

  6. [Craniospinal malformations in a twelve-year fetopathological study; the efficiency of ultrasonography in view of fetopathological investigations].

    Science.gov (United States)

    Joó, József Gábor; Beke, Artúr; Szigeti, Zsanett; Csaba, Akos; Mezei, Gábor; Tóth-Pál, Erno; Papp, Zoltán; Papp, Csaba

    2008-01-06

    Craniospinal malformations represent a heterogeneous group of congenital malformations by their morphology and etiology alike. Certain craniospinal malformations could be diagnosed as early as the dawn of ultrasonography and this group of malformations has been the focus of attention ever since. The aim of the authors was to review the main characteristics of craniospinal malformations, as well as to evaluate the efficiency of ultrasonography based on autopsy examinations during twelve years. The current study comprises the details of 339 pregnancies terminated by induced abortion for craniospinal malformation between 1995 and 2006. Maternal median age was 27 +/- 5.8 years, ranging from 15 to 47 years. In 24.5% of the cases, there was a positive obstetrical-gynaecological or genetic history. In 68.1% of the cases, ultrasonographic and autopsy findings were completely identical; in 24.2% a partial coincidence was found, but autopsy allowed for further diagnoses, while in 26 cases (7.7%) different findings were obtained by prenatal ultrasonography and fetopathological investigations. In half of the latter 26 cases, induced abortion was suggested due to hydrocephalus confirmed by ultrasonography but not justified by autopsy or the autopsy revealed the presence of other craniospinal malformation(s). It can be concluded that--in view of the diagnostic efficiency of fetopathological investigations--the ultrasonographic diagnosis of hydrocephalus should be interpreted independently from other craniospinal malformations on the basis of principles of ultrasonographic methodology and at different times.

  7. Craniospinal treatment with IMRT multi-isocentric and image-guided linear accelerator based on Gantry

    International Nuclear Information System (INIS)

    Sanz Beltran, M.; Caballero Perea, B.; Rodriguez Rodriguez, C.; Arminio Diaz, E.; Lopez Fernandez, A.; Gomez Fervienza, J. R.; Crespo Diez, P.; Cantarero Valenzuela, N.; Alvarez Sanchez, M.; Martin Martin, G.; Gomez Fervienza, J. r.; Crespo Diez, P.; Cantarero Valenzuela, N.; Alvarez Sanchez, M.; Martin Martin, G.

    2011-01-01

    The objective is the realization of craniospinal treatment with a linear accelerator equipped with gantry based on MLC, carbon fiber table and Image Guided capability. The great length of treatment (patient l,80m in height) was a great difficulty for want of full length of the longitudinal movement of the table to adequately cover the PTV, plus free metallic screws fastening the head of the table extender preventing further incidents.

  8. Hyperfractionated craniospinal radiotherapy and adjuvant chemotherapy for children with newly diagnosed medulloblastoma and other primitive neuroectodermal tumors

    International Nuclear Information System (INIS)

    Allen, Jeffrey C.; Donahue, Bernadine; DaRosso, Robert; Nirenberg, Anita

    1996-01-01

    Purpose: This single-institution Phase I/II study conducted from 1989 to 1995 evaluates the feasibility of a multi-modality protocol combining hyperfractionated craniospinal radiotherapy (HFRT) followed by adjuvant chemotherapy in 23 patients with newly diagnosed primitive neuroectodermal tumors (PNET) arising in the central nervous system. Methods and Materials: All 23 patients had a histologically confirmed PNET and were over 3 years of age at diagnosis. The eligibility criteria for PNET patients with cerebellar primaries (medulloblastoma) included either a high T stage (T3b or 4) or high M stage (M1-3). All patients with noncerebellar primaries were eligible regardless of T or M stage. The median age of the 23 patients was 9 years (mean 3-25); 11 were female. The primary tumor arose in the cerebellum in 19. Of these medulloblastoma patients, 15 had high T stages (T3b or T4) with large locally invasive tumors and no evidence of metastases (M0), constituting Group 1. Thirteen (86%) of these patients had gross total resections. Four other medulloblastoma patients had both high T and high M stages, constituting Group 2. Group 3 consisted of four other patients with exocerebellar primaries (two brain, one brain stem, and one cauda equina), three of whom were M3. Hyperfractionated radiotherapy was administered within 4 weeks of surgery. Twice-daily 1-Gy fractions were administered separated by 4-6 h. The total dose to the primary intracranial tumor and other areas of measurable intracranial disease was 72 Gy. The prophylactic craniospinal axis dose was 36 Gy, and boosts of 44-56 Gy were administered to metastatic spinal deposits. Following radiotherapy, monthly courses of multiagent chemotherapy were administered sequentially (cyclophosphamide-vincristine followed by cisplatin-etoposide followed by carboplatin-vincristine) for a total of 9 months. Results: All patients completed radiotherapy as planned. Only three patients lost >10% of their body weight. One patient

  9. Radiotherapy in metastatic diseases of the cervical spine and the craniospinal region

    International Nuclear Information System (INIS)

    Mende, U.; Braun, A.; Reiden, K.; Voth, D.; Glees, P.

    1987-01-01

    The results of large autopsy studies indicate that 20 to 30% of all patients with carcinoma will develop sooner or later bone metastases. According to the incidence of the primary tumor itself as well as to its tendency to metastasize into the skeletal system more than 80% of all bone metastases are due to neoplasms of the breast, prostate, bronchus, kidney and thyroid. Most of the metastases are found in the red marrow with an unequivocal preference to the axial skeleton. This article discusses radiotherapy in metastatic diseases of the cervical spine and the craniospinal region

  10. Pre-Irradiation Chemotherapy in High Risk Medulloblastoma

    International Nuclear Information System (INIS)

    Abd-El-Aal, H.

    2006-01-01

    Rationale: The present study evaluates the effect of pre-irradiation chemotherapy in pediatric patients with high risk medulloblastoma. Twenty-four (24) pediatric patients attended the pediatric unit of Kasr-EI-Aini Center of Radiation Oncology and Nuclear Medicine (NEMROCK) from January 2000 to January 2003. Patients and Methods: Our patients were 13 boys and II girls aged 3-12 years with a median of 6.5 years. According to Chang staging system 6 cases had T2, 14 cases had T3 A and 4 cases had T3 B, 20 cases were M0, 3 cases were M I and I case was M2. All patients were treated by initial surgery, 2 cycles of pre-irradiation chemotherapy followed by craniospinal radiation then by 4 cycles of post-radiation chemotherapy. Results: Fifteen out of the 20 patients with M0 had objective response (10CR + 5PR) and no one had disease progression after pre-irradiation chemotherapy. Among 4 patients with M0 disease, 2 patients had PR and 2 had S.D. There was no disease progression among patients who received pre-irradiation chemotherapy. The 3-year overall survival and 3-year progression-free survival; (PFS) were 50% and 51 %, respectively, Myelosuppression was the main toxic effect observed during pre-irradiation chemotherapy; however, there was no delay or interruption of craniospinal irradiation. Conclusion: Pre-irradiation chemotherapy is effective in high risk medulloblastoma and is associated with acceptable side effects. The delay in craniospinal irradiation (CSI) for about 5 weeks to receive 2 courses of chemotherapy will not significantly increase disease progression. Multiple cycles of post-irradiation chemotherapy can be given safely after C51. A larger number of patients and longer follow-up is needed to confirm the results

  11. Polarity-dependence of the defect formation in c-axis oriented ZnO by the irradiation of an 8 MeV proton beam

    Science.gov (United States)

    Koike, Kazuto; Yano, Mitsuaki; Gonda, Shun-ichi; Uedono, Akira; Ishibashi, Shoji; Kojima, Kazunobu; Chichibu, Shigefusa F.

    2018-04-01

    The polarity dependence of the radiation hardness of single-crystalline ZnO bulk crystals is studied by irradiating the Zn-polar and O-polar c-planes with an 8 MeV proton beam up to the fluence of 4.2 × 1016 p/cm2. To analyze the hardness, radiation-induced defects were evaluated using positron annihilation (PA) analysis, and the recovery by post-annealing was examined using continuous-wave photoluminescence (PL) and time-resolved photoluminescence (TRPL) measurements. It was suggested by the PA and PL analyses that the major defects in both polarities were VZnVO divacancies. While the PA data did not show the clear dependence on the polarity, the PL and TRPL results showed that the Zn-polar c-plane had a little higher radiation tolerance than that of the O-polar c-plane, which was consistent with the result that the increase in the electrical resistance by proton beam irradiation was smaller for the former one. Considering these results in total, the polarity dependence is considered to be not so large, but the Zn-polar c-plane has a little higher tolerance than that of the O-polar one.

  12. Axis Spectrometer

    International Nuclear Information System (INIS)

    Park, Sungil

    2006-01-01

    The Cold Neutron Research Facility (CNRF) project carried out by Korea Atomic Energy Research Institute (KAERI) is an effort to bring cold neutron instrumentation to Korea's only large scale research reactor, HANARO, located in Daejeon. As part of the CNRF project, a cold neutron triple-axis spectrometer (Cold-TAS) is being developed along with other five: 40 m long and 12 m long small angle neutron scattering instruments (40m-SANS and 12m-SANS), disk-chopper time-of-flight spectrometer (DC-ToF), Bio- Reflectometer (Bio-REF) and the reflectometer with vertical sample geometry (REF-V). For those cold neutron instruments, the performance of an individual instrument depends not only on its design but also on the guide that feeds cold neutrons to the instrument. Therefore, the quality of the neutron flux at an instrument position has to be checked with the specification of the instrument. As for the Cold-TAS, since the instrument requires a tall beam and a high flux of short wavelength neutrons, it was tentatively decided that it would use the cold guide 4 (CG4). The detailed specification of the guide is listed. Checking the neutron flux of the guide at the instrument position is the obvious next step

  13. Functional modeling of the craniospinal system for in-vitro parameter studies on the pathogenesis of NPH

    Directory of Open Access Journals (Sweden)

    Benninghaus Anne

    2017-09-01

    Full Text Available Normal Pressure Hydrocephalus (NPH has become a common disease in the elderly coming along with typical symptoms of dementia, gait ataxia and urinary incontinence, which make the differential diagnosis with other forms of dementia difficult. Furthermore the pathogenesis of NPH is still not understood. About 10% of all demented patients might be suffering from NPH [1]. Many hypotheses suggest that modified biomechanical boundary conditions affect the craniospinal dynamics inducing the pathogenesis of NPH. We present a novel approach for an in-vitro model of the craniospinal system to investigate important hydrodynamic influences on the system such as (dynamic compliance of the vascular system and especially the spinal subarachnoid space (SAS as well as reabsorption and hydrostatics. The experimental set-up enables the individual adjustment of relevant parameters for sensitivity analyses regarding the impact of resulting CSF dynamics on the pathogenesis of NPH.

  14. Is posture-related craniospinal compliance shift caused by jugular vein collapse? A theoretical analysis.

    Science.gov (United States)

    Gehlen, Manuel; Kurtcuoglu, Vartan; Schmid Daners, Marianne

    2017-02-16

    Postural changes are related to changes in cerebrospinal fluid (CSF) dynamics. While sitting up leads to a decrease in cranial CSF pressure, it also causes shifts in the craniospinal CSF volume and compliance distribution. We hypothesized that jugular vein collapse in upright posture is a major contributor to these shifts in CSF volume and compliance. To test this hypothesis, we implemented a mathematical lumped-parameter model of the CSF system and the relevant parts of the cardiovascular system. In this model, the CSF and the venous system are each divided into a cranial and a spinal part. The pressures in these cranial and spinal portions differ by the posture-dependent hydrostatic pressure columns in the connecting vessels. Jugular collapse is represented by a reduction of the hydrostatic pressure difference between cranial and spinal veins. The CSF pressure-volume relationship is implemented as a function of the local CSF to venous pressure gradient. This implies that an increase in CSF volume leads to a simultaneous displacement of blood from adjacent veins. CSF pulsations driven by the cardiovascular system are introduced through a pulsating cranial arterial volume. In upright posture, the implemented CSF pressure-volume relationship shifts to lower cranial CSF pressures compared to the horizontal position, leading to a decrease in cranial CSF pressure when sitting up. Concurrently, the compliance of the spinal compartment decreases while the one of the cranial compartment increases. With this, in upright posture only 10% of the CSF system's compliance is provided by the spinal compartment compared to 35% in horizontal posture. This reduction in spinal compliance is accompanied by a caudal shift of CSF volume. Also, the ability of the spinal CSF compartment to compensate for cerebral arterial volume pulsations reduces in upright posture, which in turn reduces the calculated craniospinal CSF flow pulsations. The mathematical model enabled us to isolate the

  15. Intensity-modulated radiation therapy and volumetric-modulated arc therapy for adult craniospinal irradiation—A comparison with traditional techniques

    Energy Technology Data Exchange (ETDEWEB)

    Studenski, Matthew T., E-mail: matthew.studenski@jeffersonhospital.org [Department of Radiation Oncology, Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA (United States); Shen, Xinglei; Yu, Yan; Xiao, Ying; Shi, Wenyin [Department of Radiation Oncology, Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA (United States); Biswas, Tithi [Department of Radiation Oncology, Brody School of Medicine, East Carolina University, Greenville, NC (United States); Werner-Wasik, Maria; Harrison, Amy S. [Department of Radiation Oncology, Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA (United States)

    2013-04-01

    Craniospinal irradiation (CSI) poses a challenging planning process because of the complex target volume. Traditional 3D conformal CSI does not spare any critical organs, resulting in toxicity in patients. Here the dosimetric advantages of intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) are compared with classic conformal planning in adults for both cranial and spine fields to develop a clinically feasible technique that is both effective and efficient. Ten adult patients treated with CSI were retrospectively identified. For the cranial fields, 5-field IMRT and dual 356° VMAT arcs were compared with opposed lateral 3D conformal radiotherapy (3D-CRT) fields. For the spine fields, traditional posterior-anterior (PA) PA fields were compared with isocentric 5-field IMRT plans and single 200° VMAT arcs. Two adult patients have been treated using this IMRT technique to date and extensive quality assurance, especially for the junction regions, was performed. For the cranial fields, the IMRT technique had the highest planned target volume (PTV) maximum and was the least efficient, whereas the VMAT technique provided the greatest parotid sparing with better efficiency. 3D-CRT provided the most efficient delivery but with the highest parotid dose. For the spine fields, VMAT provided the best PTV coverage but had the highest mean dose to all organs at risk (OAR). 3D-CRT had the highest PTV and OAR maximum doses but was the most efficient. IMRT provides the greatest OAR sparing but the longest delivery time. For those patients with unresectable disease that can benefit from a higher, definitive dose, 3D-CRT–opposed laterals are the most clinically feasible technique for cranial fields and for spine fields. Although inefficient, the IMRT technique is the most clinically feasible because of the increased mean OAR dose with the VMAT technique. Quality assurance of the beams, especially the junction regions, is essential.

  16. Effects of vertebral-body-sparing proton craniospinal irradiation on the spine of young pediatric patients with medulloblastoma

    Directory of Open Access Journals (Sweden)

    Iain MacEwan, MD

    2017-04-01

    Conclusion: Vertebral-body-sparing CSI with proton beam did not appear to cause increased severe spinal abnormalities in patients treated at our institution. This approach could be considered in future clinical trials in an effort to reduce toxicity and the risk of secondary malignancy and to improve adult height.

  17. Postponed Is Not Canceled: Role of Craniospinal Radiation Therapy in the Management of Recurrent Infant Medulloblastoma—An Experience From the HIT-REZ 1997 and 2005 Studies

    Energy Technology Data Exchange (ETDEWEB)

    Müller, Klaus, E-mail: Klaus.Mueller@medizin.uni-leipzig.de [Department of Radiation Oncology, University of Leipzig Medical Center, Leipzig (Germany); Mynarek, Martin [Department of Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf, Hamburg (Germany); Zwiener, Isabella [Institute for Medical Biostatistics, Epidemiology and Informatics, University of Mainz Medical Center, Mainz (Germany); Siegler, Nele [University Hospital of Essen, Pediatrics III, Essen (Germany); Zimmermann, Martina [Department of Pediatric Hematology and Oncology, Children' s Hospital, University Hospital of Bonn, Bonn (Germany); Christiansen, Hans [Department of Radiotherapy, Hannover Medical School, Hannover (Germany); Budach, Wilfried [Clinic and Policlinic for Radiation Therapy and Radiooncology, University of Düsseldorf, Düsseldorf (Germany); Henke, Guido [Department of Radiation Oncology, Kantonsspital St. Gallen, St. Gallen (Switzerland); Warmuth-Metz, Monika [Department of Neuroradiology, University of Würzburg, Würzburg (Germany); Pietsch, Torsten [Department of Neuropathology, University of Bonn Medical Center, Bonn (Germany); Hoff, Katja von [Department of Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf, Hamburg (Germany); Bueren, Andre von [Department of Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf, Hamburg (Germany); Division of Pediatric Hematology and Oncology, Department of Pediatrics and Adolescent Medicine, University Medical Center Göttingen, Göttingen (Germany); Bode, Udo [Department of Pediatric Hematology and Oncology, Children' s Hospital, University Hospital of Bonn, Bonn (Germany); and others

    2014-04-01

    Purpose: To evaluate the efficacy of craniospinal irradiation (CSI) in the management of recurrent infant medulloblastoma after surgery and chemotherapy alone. Methods and Materials: Seventeen pediatric medulloblastoma patients registered in the HIT-REZ 1997 and 2005 studies underwent CSI as salvage treatment at first recurrence. All patients had achieved complete remission after first-line treatment consisting of surgery and chemotherapy. Eleven patients showed metastatic disease at relapse. Five patients underwent surgery prior to radiation therapy, which resulted in complete resection in 1 case. In 1 patient, complete resection of the residual tumor was performed after CSI. Eleven patients received chemotherapy prior, 6 patients during and 8 patients after CSI. All patients received CSI with a median total dose of 35.2 Gy, and all but 1 received a boost to the posterior fossa (median total dose, 55.0 Gy). Metastases were boosted with an individual radiation dose, depending on their location and extent. Results: During a median follow-up time of 6.2 years since recurrence, 11 patients showed progressive disease and died. Median progression-free (overall) survival was 2.9 ± 1.1 (3.8 ± 0.8) years. Progression-free survival (PFS) rates at 1, 3, and 5 years were 88% ± 8%, 46% ± 12%, and 40% ± 12%, respectively. Overall survival (OS) rates at 1, 3, and 5 years were 94% ± 6%, 58% ± 12%, and 39% ± 12%, respectively. For 11 patients with classic medulloblastoma, 3-year (and 5-year) PFS and OS were 62% ± 15% and 72% ± 14% (52% ± 16% and 51% ± 16%), respectively. On univariate analysis, metastatic disease was not associated with poorer progression-free and overall survival. Conclusions: Our results suggest that salvage treatment of relapsed medulloblastomas consisting of CSI and chemotherapy offers a second chance for cure, even for patients with classic histological findings. Metastatic disease at relapse did not have an impact

  18. Triple-axis spectrometer

    International Nuclear Information System (INIS)

    Toeroek, Gy.

    2001-01-01

    A triple-axis spectrometer has been designed for structural and dynamical studies of condensed matter. Because of the limited number of other operational equipment the triple axis spectrometer was used in a multi purpose regime, e.g. high resolution diffractometry, strain analysis, reflectometry, quasielastic and inelastic scattering. A polarization setup was also tested on this spectrometer. (R.P.)

  19. Gut-brain axis

    NARCIS (Netherlands)

    Romijn, Johannes A.; Corssmit, Eleonora P.; Havekes, Louis M.; Pijl, Hanno

    2008-01-01

    To summarize recent studies on the regulation and the functions of the gut-brain axis. Visual cues of food and food intake interact with the gut-brain axis at the level of the hypothalamus. However, the hypothalamic response to glucose intake is considerably altered in patients with type 2 diabetes

  20. SU-E-T-92: Achieving Desirable Lung Doses in Total Body Irradiation Based On in Vivo Dosimetry and Custom Tissue Compensation

    Energy Technology Data Exchange (ETDEWEB)

    Cui, G; Shiu, A; Zhou, S; Cui, J; Ballas, L [Univ Southern California, Los Angeles, CA (United States)

    2015-06-15

    Purpose: To achieve desirable lung doses in total body irradiation (TBI) based on in vivo dosimetry and custom tissue compensation. Methods: The 15 MV photon beam of a Varian TrueBeam STx linac was used for TBI. Patients were positioned in the lateral decubitus position for AP/PA treatment delivery. Dose was calculated using the midpoint of the separation distance across the patient’s umbilicus. Patients received 200 cGy twice daily for 3 days. The dose rate at the patient’s midplane was approximately 10 cGy/min. Cerrobend blocks with a 5-HVL thickness were used for the primary lung shielding. A custom styrofoam holder for rice-flour filled bags was created based on the lung block cutouts. This was used to provide further lung shielding based on in vivo dose measurements. Lucite plates and rice-flour bags were placed in the head, neck, chest, and lower extremity regions during the treatment to compensate for the beam off-axis output variations. Two patients were included in the study. Patients 1 and 2 received a craniospinal treatment (1080 cGy) and a mediastinum treatment (2520 cGy), respectively, before the TBI. During the TBI nanoDot dosimeters were placed on the patient skin in the forehead, neck, umbilicus, and lung regions for dose monitoring. The doses were readout immediately after the treatment. Based on the readings, fine tuning of the thickness of the rice-flour filled bags was exploited to achieve the desirable lung doses. Results: For both patients the mean lung doses, which took into consideration all treatments, were controlled within 900 +/−10% cGy, as desired. Doses to the forehead, neck, and umbilicus were achieved within +/−10% of the prescribed dose (1200 cGy). Conclusion: A reliable and robust method was developed to achieve desirable lung doses and uniform body dose in TBI based on in vivo dosimetry and custom tissue compensator.

  1. Vertical axis wind turbine

    International Nuclear Information System (INIS)

    Obretenov, V.; Tsalov, T.; Chakarov, T.

    2012-01-01

    In recent years, the interest in wind turbines with vertical axis noticeably increased. They have some important advantages: low cost, relatively simple structure, reliable packaging system of wind aggregate long period during which require no maintenance, low noise, independence of wind direction, etc.. The relatively low efficiency, however, makes them applicable mainly for small facilities. The work presents a methodology and software for approximately aerodynamic design of wind turbines of this type, and also analyzed the possibility of improving the efficiency of their workflow

  2. Vertical axis wind turbines

    Science.gov (United States)

    Krivcov, Vladimir [Miass, RU; Krivospitski, Vladimir [Miass, RU; Maksimov, Vasili [Miass, RU; Halstead, Richard [Rohnert Park, CA; Grahov, Jurij [Miass, RU

    2011-03-08

    A vertical axis wind turbine is described. The wind turbine can include a top ring, a middle ring and a lower ring, wherein a plurality of vertical airfoils are disposed between the rings. For example, three vertical airfoils can be attached between the upper ring and the middle ring. In addition, three more vertical airfoils can be attached between the lower ring and the middle ring. When wind contacts the vertically arranged airfoils the rings begin to spin. By connecting the rings to a center pole which spins an alternator, electricity can be generated from wind.

  3. Dose Distribution of Gamma Irradiators

    International Nuclear Information System (INIS)

    Park, Seung Woo; Shin, Sang Hun; Son, Ki Hong; Lee, Chang Yeol; Kim, Kum Bae; Jung, Hai Jo; Ji, Young Hoon

    2010-01-01

    Gamma irradiator using Cs-137 have been widely utilized to the irradiation of cell, blood, and animal, and the dose measurement and education. The Gamma cell 3000 Elan (Nordion International, Kanata, Ontario, Canada) irradiator was installed in 2003 with Cs-137 and dose rate of 3.2 Gy/min. And the BioBeam 8000 (Gamma-Service Medical GmbH, Leipzig, Germany) irradiator was installed in 2008 with Cs-137 and dose rate of 3.5 Gy/min. Our purpose was to evaluate the practical dosimetric problems associated with inhomogeneous dose distribution within the irradiated volume in open air state using glass dosimeter and Gafchromic EBT film dosimeter for routine Gamma irradiator dosimetry applications at the KIRAMS and the measurements were compared with each other. In addition, an user guideline for useful utilization of the device based on practical dosimetry will be prepared. The measurement results of uniformity of delivered dose within the device showed variation more than 14% between middle point and the lowest position at central axis. Therefore, to maintain dose variation within 10%, the criteria of useful dose distribution, for research radiation effects, the irradiated specimen located at central axis of the container should be placed within 30 mm from top and bottom surface, respectively. In addition, for measurements using the film, the variations of dose distribution were more then 50% for the case of less than 10 second irradiation, mostly within 20% for the case of more than 20 second irradiation, respectively. Therefore, the irradiation experiments using the BioBeam 8000 irradiator are recommended to be used for specimen required at least more than 20 second irradiation time.

  4. Food irradiation

    International Nuclear Information System (INIS)

    Soothill, R.

    1987-01-01

    The issue of food irradiation has become important in Australia and overseas. This article discusses the results of the Australian Consumers' Association's (ACA) Inquiry into food irradiation, commissioned by the Federal Government. Issues discussed include: what is food irradiation; why irradiate food; how much food is consumer rights; and national regulations

  5. Food irradiation

    International Nuclear Information System (INIS)

    Munasiri, M.A.

    1990-01-01

    Gives details of sources used for food irradiation, brief description of the process, safety of food irradiation process, practical applications and the amount of doses used for spices, condiments, mangoes etc., limitations of food irradiation, international status of clearance of irradiated foods, versatility of the process

  6. Food irradiation

    International Nuclear Information System (INIS)

    Lindqvist, H.

    1996-01-01

    This paper is a review of food irradiation and lists plants for food irradiation in the world. Possible applications for irradiation are discussed, and changes induced in food from radiation, nutritional as well as organoleptic, are reviewed. Possible toxicological risks with irradiated food and risks from alternative methods for treatment are also brought up. Ways to analyze weather food has been irradiated or not are presented. 8 refs

  7. Gut Microbiota-brain Axis.

    Science.gov (United States)

    Wang, Hong-Xing; Wang, Yu-Ping

    2016-10-05

    To systematically review the updated information about the gut microbiota-brain axis. All articles about gut microbiota-brain axis published up to July 18, 2016, were identified through a literature search on PubMed, ScienceDirect, and Web of Science, with the keywords of "gut microbiota", "gut-brain axis", and "neuroscience". All relevant articles on gut microbiota and gut-brain axis were included and carefully reviewed, with no limitation of study design. It is well-recognized that gut microbiota affects the brain's physiological, behavioral, and cognitive functions although its precise mechanism has not yet been fully understood. Gut microbiota-brain axis may include gut microbiota and their metabolic products, enteric nervous system, sympathetic and parasympathetic branches within the autonomic nervous system, neural-immune system, neuroendocrine system, and central nervous system. Moreover, there may be five communication routes between gut microbiota and brain, including the gut-brain's neural network, neuroendocrine-hypothalamic-pituitary-adrenal axis, gut immune system, some neurotransmitters and neural regulators synthesized by gut bacteria, and barrier paths including intestinal mucosal barrier and blood-brain barrier. The microbiome is used to define the composition and functional characteristics of gut microbiota, and metagenomics is an appropriate technique to characterize gut microbiota. Gut microbiota-brain axis refers to a bidirectional information network between the gut microbiota and the brain, which may provide a new way to protect the brain in the near future.

  8. Gut Microbiota-brain Axis

    OpenAIRE

    Wang, Hong-Xing; Wang, Yu-Ping

    2016-01-01

    Objective: To systematically review the updated information about the gut microbiota-brain axis. Data Sources: All articles about gut microbiota-brain axis published up to July 18, 2016, were identified through a literature search on PubMed, ScienceDirect, and Web of Science, with the keywords of “gut microbiota”, “gut-brain axis”, and “neuroscience”. Study Selection: All relevant articles on gut microbiota and gut-brain axis were included and carefully reviewed, with no limitation of s...

  9. Craniospinal treatment with IMRT multi-isocentric and image-guided linear accelerator based on Gantry; Tratamiento craneoespinal multi-isocentrico con IMRT y guiado por imagen en acelerador lineal basado en Gantry

    Energy Technology Data Exchange (ETDEWEB)

    Sanz Beltran, M.; Caballero Perea, B.; Rodriguez Rodriguez, C.; Arminio Diaz, E.; Lopez Fernandez, A.; Gomez Fervienza, J. R.; Crespo Diez, P.; Cantarero Valenzuela, N.; Alvarez Sanchez, M.; Martin Martin, G.; Gomez Fervienza, J. r.; Crespo Diez, P.; Cantarero Valenzuela, N.; Alvarez Sanchez, M.; Martin Martin, G.

    2011-07-01

    The objective is the realization of craniospinal treatment with a linear accelerator equipped with gantry based on MLC, carbon fiber table and Image Guided capability. The great length of treatment (patient l, 80m in height) was a great difficulty for want of full length of the longitudinal movement of the table to adequately cover the PTV, plus free metallic screws fastening the head of the table extender preventing further incidents.

  10. SU-E-CAMPUS-T-03: Development and Implementation of An Anthropomorphic Pediatric Spine Phantom for the Assessment of Craniospinal Irradiation Procedures in Proton Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, D; Summers, P; Followill, D; Sahoo, N; Mahajan, A; Stingo, F; Kry, S [UT MD Anderson Cancer Center, Houston, TX (United States)

    2014-06-15

    Purpose: To design an anthropomorphic pediatric spine phantom for use in the evaluation of proton therapy facilities for clinical trial participation by the Imaging and Radiation Oncology Core (IROC) Houston QA Center (formerly RPC). Methods: This phantom was designed to perform an end-to-end audit of the proton spine treatment process, including simulation, dose calculation by the treatment planning system (TPS), and proton treatment delivery. The design incorporated materials simulating the thoracic spinal column of a pediatric patient, along with two thermoluminescent dosimeter (TLD)-100 capsules and radiochromic film embedded in the phantom for dose evaluation. Fourteen potential materials were tested to determine relative proton stopping power (RSP) and Hounsfield unit (HU) values. Each material was CT scanned at 120kVp, and the RSP was obtained from depth ionization scans using the Zebra multilayer ion chamber (MLIC) at two energies: 160 MeV and 250 MeV. To determine tissue equivalency, the measured RSP for each material was compared to the RSP calculated by the Eclipse TPS for a given HU. Results: The materials selected as bone, tissue, and cartilage substitutes were Techron HPV Bearing Grade (Boedeker Plastics, Inc.), solid water, and blue water, respectively. The RSP values did not differ by more than 1.8% between the two energies. The measured RSP for each selected material agreed with the RSP calculated by the Eclipse TPS within 1.2%. Conclusion: An anthropomorphic pediatric proton spine phantom was designed to evaluate proton therapy delivery. The inclusion of multiple tissue substitutes increases heterogeneity and the level of difficulty for institutions to successfully treat the phantom. The following attributes will be evaluated: absolute dose agreement, distal range, field width, junction match and right/left dose profile alignment. The phantom will be tested at several institutions using a 5% dose agreement criterion, and a 5%/3mm gamma analysis criterion for the film planes. Work supported by grants CA10953, CA059267, and CA81647 (NCI, DHHS)

  11. RADIATION THERAPY QUALITY IN CCG/POG INTERGROUP 9961: IMPLICATIONS FOR CRANIOSPINAL IRRADIATION AND THE POSTERIOR FOSSA BOOST IN FUTURE MEDULLOBLASTOMA TRIALS

    Directory of Open Access Journals (Sweden)

    Bernadine eDonahue

    2012-12-01

    Full Text Available Purpose: Associations of RT deviations and outcomes in medulloblastoma have not been defined well, particularly in the era of reduced-dose CSI and chemotherapy. The aim of this study is to evaluate the quality of RT on CCG/POG 9961 and analyze associations of RT deviations with outcome.Methods and Materials: Major volume deviations were assessed based on the distance from specified anatomical region to field edge. We investigated associations of RT deviations with progression-free survival (PFS, overall survival (OS, and explored associations with demographics and clinical variables.Results: Of the 308 patients who were evaluable for volume deviations, 101 patients (33% did not have any. Of the remaining 207 patients, 50% had only minor deviations, 29% had only major deviations, and 21% had both minor and major deviations. Of the patients with major deviations, 73% had a single major deviation. The most common major deviation was in the cribriform plate region, followed by the posterior fossa; posterior fossa deviations resulted from treating less than whole posterior fossa. There were no significant differences in PFS or OS between patients with deviations and those without. There was no evidence of associations of deviations with patient age. Conclusions: Approximately one-third of patients had major volume deviations. There was no evidence of a significant association between these and outcome. This lack of correlation likely reflects the current high quality of radiation therapy delivered in COG institutions, our strict definition of volume deviations, and the relatively few instances of multiple major deviations in individual patients. In is noteworthy that the types of posterior fossa volume deviations observed in this study were not adversely associated with outcome. As we move forward, quality assurance will continue to play an important role to ensure that deviations on study do not influence study outcome.

  12. Food irradiation

    International Nuclear Information System (INIS)

    Sato, Tomotaro; Aoki, Shohei

    1976-01-01

    Definition and significance of food irradiation were described. The details of its development and present state were also described. The effect of the irradiation on Irish potatoes, onions, wiener sausages, kamaboko (boiled fish-paste), and mandarin oranges was evaluated; and healthiness of food irradiation was discussed. Studies of the irradiation equipment for Irish potatoes in a large-sized container, and the silo-typed irradiation equipment for rice and wheat were mentioned. Shihoro RI center in Hokkaido which was put to practical use for the irradiation of Irish potatoes was introduced. The state of permission of food irradiation in foreign countries in 1975 was introduced. As a view of the food irradiation in the future, its utilization for the prevention of epidemics due to imported foods was mentioned. (Serizawa, K.)

  13. Gamma irradiator

    International Nuclear Information System (INIS)

    Simonet, G.

    1986-09-01

    Fiability of devices set around reactors depends on material resistance under irradiation noticeably joints, insulators, which belongs to composition of technical, safety or physical incasurement devices. The irradiated fuel elements, during their desactivation in a pool, are an interesting gamma irradiation device to simulate damages created in a nuclear environment. The existing facility at Osiris allows to generate an homogeneous rate dose in an important volume. The control of the element distances to irradiation box allows to control this dose rate [fr

  14. Food irradiation

    International Nuclear Information System (INIS)

    Duchacek, V.

    1989-01-01

    The ranges of doses used for food irradiation and their effect on the processed foods are outlined. The wholesomeness of irradiated foods is discussed. The present food irradiation technology development in the world is described. A review of the irradiated foods permitted for public consumption, the purposes of food irradiaton, the doses used and a review of the commercial-scale food irradiators are tabulated. The history and the present state of food processing in Czechoslovakia are described. (author). 1 fig., 3 tabs., 13 refs

  15. Food irradiation

    International Nuclear Information System (INIS)

    Macklin, M.

    1987-01-01

    The Queensland Government has given its support the establishment of a food irradiation plant in Queensland. The decision to press ahead with a food irradiation plant is astonishing given that there are two independent inquiries being carried out into food irradiation - a Parliamentary Committee inquiry and an inquiry by the Australian Consumers Association, both of which have still to table their Reports. It is fair to assume from the Queensland Government's response to date, therefore, that the Government will proceed with its food irradiation proposals regardless of the outcomes of the various federal inquiries. The reasons for the Australian Democrats' opposition to food irradiation which are also those of concerned citizens are outlined

  16. Three axis attitude control system

    Science.gov (United States)

    Studer, Philip A. (Inventor)

    1988-01-01

    A three-axis attitude control system for an orbiting body comprised of a motor driven flywheel supported by a torque producing active magnetic bearing is described. Free rotation of the flywheel is provided about its central axis and together with limited angular torsional deflections of the flywheel about two orthogonal axes which are perpendicular to the central axis. The motor comprises an electronically commutated DC motor, while the magnetic bearing comprises a radially servoed permanent magnet biased magnetic bearing capable of producing cross-axis torques on the flywheel. Three body attitude sensors for pitch, yaw and roll generate respective command signals along three mutually orthogonal axes (x, y, z) which are coupled to circuit means for energizing a set of control coils for producing torques about two of the axes (x and y) and speed control of the flywheel about the third (z) axis. An energy recovery system, which is operative during motor deceleration, is also included which permits the use of a high-speed motor to perform effectively as a reactive wheel suspended in the magnetic bearing.

  17. Vertical axis wind turbine airfoil

    Science.gov (United States)

    Krivcov, Vladimir; Krivospitski, Vladimir; Maksimov, Vasili; Halstead, Richard; Grahov, Jurij Vasiljevich

    2012-12-18

    A vertical axis wind turbine airfoil is described. The wind turbine airfoil can include a leading edge, a trailing edge, an upper curved surface, a lower curved surface, and a centerline running between the upper surface and the lower surface and from the leading edge to the trailing edge. The airfoil can be configured so that the distance between the centerline and the upper surface is the same as the distance between the centerline and the lower surface at all points along the length of the airfoil. A plurality of such airfoils can be included in a vertical axis wind turbine. These airfoils can be vertically disposed and can rotate about a vertical axis.

  18. Gut Microbiota-brain Axis

    Science.gov (United States)

    Wang, Hong-Xing; Wang, Yu-Ping

    2016-01-01

    Objective: To systematically review the updated information about the gut microbiota-brain axis. Data Sources: All articles about gut microbiota-brain axis published up to July 18, 2016, were identified through a literature search on PubMed, ScienceDirect, and Web of Science, with the keywords of “gut microbiota”, “gut-brain axis”, and “neuroscience”. Study Selection: All relevant articles on gut microbiota and gut-brain axis were included and carefully reviewed, with no limitation of study design. Results: It is well-recognized that gut microbiota affects the brain's physiological, behavioral, and cognitive functions although its precise mechanism has not yet been fully understood. Gut microbiota-brain axis may include gut microbiota and their metabolic products, enteric nervous system, sympathetic and parasympathetic branches within the autonomic nervous system, neural-immune system, neuroendocrine system, and central nervous system. Moreover, there may be five communication routes between gut microbiota and brain, including the gut-brain's neural network, neuroendocrine-hypothalamic-pituitary-adrenal axis, gut immune system, some neurotransmitters and neural regulators synthesized by gut bacteria, and barrier paths including intestinal mucosal barrier and blood-brain barrier. The microbiome is used to define the composition and functional characteristics of gut microbiota, and metagenomics is an appropriate technique to characterize gut microbiota. Conclusions: Gut microbiota-brain axis refers to a bidirectional information network between the gut microbiota and the brain, which may provide a new way to protect the brain in the near future. PMID:27647198

  19. Foodstuff irradiation

    International Nuclear Information System (INIS)

    1982-01-01

    Report written on behalf of the Danish Food Institute summarizes national and international rules and developments within food irradiation technology, chemical changes in irradiated foodstuffs, microbiological and health-related aspects of irradiation and finally technological prospects of this conservation form. Food irradiatin has not been hitherto applied in Denmark. Radiation sources and secondary radiation doses in processed food are characterized. Chemical changes due to irradiation are compared to those due to p.ex. food heating. Toxicological and microbiological tests and their results give no unequivocal answer to the problem whether a foodstuff has been irradiated. The most likely application fields in Denmark are for low radiation dosis inhibition of germination, riping delay and insecticide. Medium dosis (1-10 kGy) can reduce bacteria number while high dosis (10-50 kGy) will enable total elimination of microorganisms and viruses. Food irradiation can be acceptable as technological possibility with reservation, that further studies follow. (EG)

  20. Hemibody irradiation

    International Nuclear Information System (INIS)

    Schen, B.C.; Mella, O.; Dahl, O.

    1992-01-01

    In a large number of cancer patients, extensive skeletal metastases or myelomatosis induce vast suffering, such as intolerable pain and local complications of neoplastic bone destruction. Analgetic drugs frequently do not yield sufficient palliation. Irradiation of local fields often has to be repeated, because of tumour growth outside previously irradiated volumes. Wide field irradiation of the lower or upper half of the body causes significant relief of pain in most patients. Adequate pretreatment handling of patients, method of irradiation, and follow-up are of importance to reduce side effects, and are described as they are carried out at the Department of Oncology, Haukeland Hospital, Norway. 16 refs., 2 figs

  1. Late adverse effects of whole cranial irradiation in childhood hematological disorders

    Energy Technology Data Exchange (ETDEWEB)

    Someya, Masanori; Nakata, Kensei; Nagakura, Hisayasu; Oouchi, Atsushi; Sakata, Kohichi; Hareyama, Masato [Sapporo Medical Coll. (Japan)

    2003-03-01

    The purpose of this study was to examine the late adverse effects of childhood hematological disorders treated with chemotherapy and radiotherapy including whole cranial irradiation at Sapporo Medical University Hospital. Twenty-eight patients were treated with chemotherapy and 18-24 Gy of prophylactic cranial irradiation (PCI) for acute lymphoblastic leukemia (ALL), and 14 patients were treated with 3-12.8 Gy of total body irradiation (TBI) and bone marrow transplantation (BMT) for ALL, acute myelogenous leukemia (AML), chronic myelogenous leukemia (CML), myelodysplastic syndrome (MDS), malignant lymphoma, and aplastic anemia (AA). Age at diagnosis ranged from 2 to 15 years old, and 28 were males and 14 were females. All patients were disease-free more than 2 years after diagnosis. Of 42 patients, 4 patients had decreased height (less than -2 S.D.), 3 patients required hormone replacement therapy, 2 patients had mental retardation, 3 patients had leukoencephalopathy, and 1 patient had a second malignancy. Except for the cases of decreased height, 3 of 7 late adverse effects were occurred in patients who had relapse of disease, and the risk of the adverse effects seemed to be higher for those patients whose doses of PCI were 22 Gy or more, or who received an additional craniospinal irradiation due to relapse of disease, and 18 Gy of PCI did not increase the risk of adverse effects. (author)

  2. Food irradiation

    International Nuclear Information System (INIS)

    Mercader, J.P.; Emily Leong

    1985-01-01

    The paper discusses the need for effective and efficient technologies in improving the food handling system. It defines the basic premises for the development of food handling. The application of food irradiation technology is briefly discussed. The paper points out key considerations for the adoption of food irradiation technology in the ASEAN region (author)

  3. Food irradiation

    International Nuclear Information System (INIS)

    Goodburn, K.E.

    1987-01-01

    The use of food preservation by irradiation over 30 years is reviewed in outline. Sprout inhibition, soft fruit preservation, suppression of salmonella in poultry, radiolytic products in foods, the detection of irradiated foods and safety studies so far are considered. (U.K.)

  4. Irradiation proctitis

    International Nuclear Information System (INIS)

    Minami, Akira

    1977-01-01

    Literatures on late rectal injuries are discussed, referring to two patients with uterine cervical cancer in whom irradiation proctitis occurred after telecobalt irradiation following uterine extirpation. To one patients, a total of 5000 rads was irradiated, dividing into 250 rads at one time, and after 3 months, irradiation with a total of 2000 rads, dividing into 200 rads at one time, was further given. In another one patient, two parallel opposing portal irradiation with a total of 6000 rads was given. About a year after the irradiation, rectal injuries and cystitis, accompanying with hemorrhage, were found in both of the patients. Rectal amputation and proctotoreusis were performed. Cystitis was treated by cystic irradiation in the urological department. Pathohistological studies of the rectal specimen revealed atrophic mucosa, and dilatation of the blood vessels and edema in the colonic submucosa. Incidence of this disease, term when the disease occurs, irradiation dose, type of the disease, treatment and prevention are described on the basis of the literatures. (Kanao, N.)

  5. Food irradiation

    International Nuclear Information System (INIS)

    Matsuyama, Akira

    1990-01-01

    This paper reviews researches, commentaries, and conference and public records of food irradiation, published mainly during the period 1987-1989, focusing on the current conditions of food irradiation that may pose not only scientific or technologic problems but also political issues or consumerism. Approximately 50 kinds of food, although not enough to fill economic benefit, are now permitted for food irradiation in the world. Consumerism is pointed out as the major factor that precludes the feasibility of food irradiation in the world. In the United States, irradiation is feasible only for spices. Food irradiation has already been feasible in France, Hollands, Belgium, and the Soviet Union; has under consideration in the Great Britain, and has been rejected in the West Germany. Although the feasibility of food irradiation is projected to increase gradually in the future, commercial success or failure depends on the final selection of consumers. In this respect, the role of education and public information are stressed. Meat radicidation and recent progress in the method for detecting irradiated food are referred to. (N.K.) 128 refs

  6. Food irradiation

    International Nuclear Information System (INIS)

    Webb, T.; Lang, T.

    1990-01-01

    There is a growing tendency worldwide to apply ionizing radiation for food preservation, or for delaying growth or ripening processes. However, research into the effects of such irradiation with ionizing radiation is lagging behind, leaving the knowledge about effects and possible hazards incomplete. The authors very carefully have analysed the available research results and present a detailed account of the current scientific knowledge and assessments. Their conclusion is: irradiated food is to be considered noxious unless its wholesomeness has been unambiguously proven. Consumers so far had not much chance to raise their voice in the debate about the wholesomeness of food irradiation, or have not been heard, the authors say. They call for establishing a European and a worldwide information network to bring together opponents to and information speaking against food irradiation, in order to create a counterweight to the market strategies of the pro-irradiation industry, and to launch initiatives on the political level. (orig./HP) [de

  7. Mobile gamma-irradiation robot

    International Nuclear Information System (INIS)

    Teply, J.; Vocilka, J.; Stetka, R.; Vins, J.; Krotil, J.; Franek, C.; Garba, A.

    1993-01-01

    A source container with 98 TBq of 137 Cs and shielding made from depleted uranium has the total weight of 264 kg, height of 0.370 and diameter 0.272 m is described. The container is joined to accessories allowing movement of the radiation beam. The dose rate at a distance of 0.4 m in the beam axis is 50 Gy/h. Various technical means are available for manipulation and transport. The irradiation process proceeds according to a precalculated program. Safety measures have been taken to secure the possible application of the irradiation plant for the radiopreservation of cultural objects. The licence from health physics authorities has been obtained. The first irradiation process performed is described. (author)

  8. Food irradiation

    International Nuclear Information System (INIS)

    Cormick, C.

    1987-01-01

    The advantages and disadvantages of food irradiation are discussed. Research into food irradiation has been going on for 40 years, yet studies have yet to demonstrate conclusively whether it is safe or harmful. The Australian House of Representatives has established an inquiry into food irradiation conducted by the Standing Committee on Environment and Conservation. It will inquire into the use of ionising radiation for commercial sterilisation, disinfestation, food preservation and other purposes with particular reference to human health and safety, environmental impacts and the adequacy of assessment and regulatory procedures

  9. Food irradiation

    International Nuclear Information System (INIS)

    Paganini, M.C.

    1991-06-01

    Food treatment by means of ionizing energy, or irradiation, is an innovative method for its preservation. In order to treat important volumes of food, it is necessary to have industrial irradiation installations. The effect of radiations on food is analyzed in the present special work and a calculus scheme for an Irradiation Plant is proposed, discussing different aspects related to its project and design: ionizing radiation sources, adequate civil work, security and auxiliary systems to the installations, dosimetric methods and financing evaluation methods of the project. Finally, the conceptual design and calculus of an irradiation industrial plant of tubercles is made, based on the actual needs of a specific agricultural zone of our country. (Author) [es

  10. Food irradiation

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    Food preservation by irradiation is one part of Eisenhower's Atoms for Peace program that is enjoying renewed interest. Classified as a food additive by the Food, Drug, and Cosmetic Act of 1958 instead of a processing technique, irradiation lost public acceptance. Experiments have not been done to prove that there are no health hazards from gamma radiation, but there are new pressures to get Food and Drug Administration approval for testing in order to make commercial use of some radioactive wastes. Irradiation causes chemical reactions and nutritional changes, including the destruction of several vitamins, as well as the production of radiolytic products not normally found in food that could have adverse effects. The author concludes that, lacking epidemiological evidence, willing buyers should be able to purchase irradiated food as long as it is properly labeled

  11. Bowel sparing in pediatric cranio-spinal radiotherapy: a comparison of combined electron and photon and helical TomoTherapy techniques to a standard photon method

    International Nuclear Information System (INIS)

    Harron, Elizabeth; Lewis, Joanne

    2012-01-01

    The aim of this study was to compare the dose to organs at risk (OARs) from different craniospinal radiotherapy treatment approaches available at the Northern Centre for Cancer Care (NCCC), with a particular emphasis on sparing the bowel. Method: Treatment plans were produced for a pediatric medulloblastoma patient with inflammatory bowel disease using 3D conformal 6-MV photons (3DCP), combined 3D 6-MV photons and 18-MeV electrons (3DPE), and helical photon TomoTherapy (HT). The 3DPE plan was a modification of the standard 3DCP technique, using electrons to treat the spine inferior to the level of the diaphragm. The plans were compared in terms of the dose-volume data to OARs and the nontumor integral dose. Results: The 3DPE plan was found to give the lowest dose to the bowel and the lowest nontumor integral dose of the 3 techniques. However, the coverage of the spine planning target volume (PTV) was least homogeneous using this technique, with only 74.6% of the PTV covered by 95% of the prescribed dose. HT was able to achieve the best coverage of the PTVs (99.0% of the whole-brain PTV and 93.1% of the spine PTV received 95% of the prescribed dose), but delivered a significantly higher integral dose. HT was able to spare the heart, thyroid, and eyes better than the linac-based techniques, but other OARs received a higher dose. Conclusions: Use of electrons was the best method for reducing the dose to the bowel and the integral dose, at the expense of compromised spine PTV coverage. For some patients, HT may be a viable method of improving dose homogeneity and reducing selected OAR doses.

  12. Fruit irradiation

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    Food spoilage is a common problem when marketing agricultural products. Promising results have already been obtained on a number of food irradiating applications. A process is described in this paper where irradiation of sub-tropical fruits, especially mangoes and papayas, combined with conventional heat treatment results in effective insect and fungal control, delays ripening and greatly improves the quality of fruit at both export and internal markets

  13. Blood irradiation

    International Nuclear Information System (INIS)

    Chandy, Mammen

    1998-01-01

    Viable lymphocytes are present in blood and cellular blood components used for transfusion. If the patient who receives a blood transfusion is immunocompetent these lymphocytes are destroyed immediately. However if the patient is immunodefficient or immunosuppressed the transfused lymphocytes survive, recognize the recipient as foreign and react producing a devastating and most often fatal syndrome of transfusion graft versus host disease [T-GVHD]. Even immunocompetent individuals can develop T-GVHD if the donor is a first degree relative since like the Trojan horse the transfused lymphocytes escape detection by the recipient's immune system, multiply and attack recipient tissues. T-GVHD can be prevented by irradiating the blood and different centers use doses ranging from 1.5 to 4.5 Gy. All transfusions where the donor is a first degree relative and transfusions to neonates, immunosuppressed patients and bone marrow transplant recipients need to be irradiated. Commercial irradiators specifically designed for irradiation of blood and cellular blood components are available: however they are expensive. India needs to have blood irradiation facilities available in all large tertiary institutions where immunosuppressed patients are treated. The Atomic Energy Commission of India needs to develop a blood irradiator which meets international standards for use in tertiary medical institutions in the country. (author)

  14. Tissue irradiator

    International Nuclear Information System (INIS)

    Hungate, F.P.; Riemath, W.F.; Bunnell, L.R.

    1975-01-01

    A tissue irradiator is provided for the in-vivo irradiation of body tissue. The irradiator comprises a radiation source material contained and completely encapsulated within vitreous carbon. An embodiment for use as an in-vivo blood irradiator comprises a cylindrical body having an axial bore therethrough. A radioisotope is contained within a first portion of vitreous carbon cylindrically surrounding the axial bore, and a containment portion of vitreous carbon surrounds the radioisotope containing portion, the two portions of vitreous carbon being integrally formed as a single unit. Connecting means are provided at each end of the cylindrical body to permit connections to blood-carrying vessels and to provide for passage of blood through the bore. In a preferred embodiment, the radioisotope is thulium-170 which is present in the irradiator in the form of thulium oxide. A method of producing the preferred blood irradiator is also provided, whereby nonradioactive thulium-169 is dispersed within a polyfurfuryl alcohol resin which is carbonized and fired to form the integral vitreous carbon body and the device is activated by neutron bombardment of the thulium-169 to produce the beta-emitting thulium-170

  15. Food irradiation

    International Nuclear Information System (INIS)

    1991-01-01

    Processing of food with low levels of radiation has the potential to contribute to reducing both spoilage of food during storage - a particular problem in developing countries - and the high incidence of food-borne disease currently seen in all countries. Approval has been granted for the treatment of more than 30 products with radiation in over 30 countries but, in general, governments have been slow to authorize the use of this new technique. One reason for this slowness is a lack of understanding of what food irradiation entails. This book aims to increase understanding by providing information on the process of food irradiation in simple, non-technical language. It describes the effects that irradiation has on food, and the plant and equipment that are necessary to carry it out safely. The legislation and control mechanisms required to ensure the safety of food irradiation facilities are also discussed. Education is seen as the key to gaining the confidence of the consumers in the safety of irradiated food, and to promoting understanding of the benefits that irradiation can provide. (orig.) With 4 figs., 1 tab [de

  16. Food irradiation

    International Nuclear Information System (INIS)

    Migdal, W.

    1995-01-01

    A worldwide standard on food irradiation was adopted in 1983 by codex Alimentarius Commission of the Joint Food Standard Programme of the Food and Agriculture Organization (FAO) of the United Nations and The World Health Organization (WHO). As a result, 41 countries have approved the use of irradiation for treating one or more food items and the number is increasing. Generally, irradiation is used to: food loses, food spoilage, disinfestation, safety and hygiene. The number of countries which use irradiation for processing food for commercial purposes has been increasing steadily from 19 in 1987 to 33 today. In the frames of the national programme on the application of irradiation for food preservation and hygienization an experimental plant for electron beam processing has been established in Inst. of Nuclear Chemistry and Technology. The plant is equipped with a small research accelerator Pilot (19 MeV, 1 kW) and industrial unit Electronika (10 MeV, 10 kW). On the basis of the research there were performed at different scientific institutions in Poland, health authorities have issued permissions for irradiation for; spices, garlic, onions, mushrooms, potatoes, dry mushrooms and vegetables. (author)

  17. A systematic comparison of on-axis and off-axis transmission Kikuchi diffraction

    DEFF Research Database (Denmark)

    Niessen, F.; Burrows, A.; Fanta, A. Bastos da Silva

    2018-01-01

    Abstract The capabilities of the novel on-axis transmission Kikuchi diffraction (TKD) technique were explored in a systematic comparison with conventional off-axis TKD. The effect of experimental parameters on the appearance of on-axis and off-axis Kikuchi patterns was measured and discussed. In ...

  18. Food irradiation

    International Nuclear Information System (INIS)

    Beishon, J.

    1991-01-01

    Food irradiation has been the subject of concern and controversy for many years. The advantages of food irradiation include the reduction or elimination of dangerous bacterial organisms, the control of pests and insects which destroy certain foods, the extension of the shelf-life of many products, for example fruit, and its ability to treat products such as seafood which may be eaten raw. It can also replace existing methods of treatment which are believed to have hazardous side-effects. However, after examining the evidence produced by the proponents of food irradiation, the author questions whether it has any major contribution to make to the problems of foodborne diseases or world food shortages. More acceptable solutions, he suggests, may be found in educating food handlers to ensure that hygienic conditions prevail in the production, storage and serving of food. (author)

  19. Irradiance gradients

    International Nuclear Information System (INIS)

    Ward, G.J.; Heckbert, P.S.; Technische Hogeschool Delft

    1992-04-01

    A new method for improving the accuracy of a diffuse interreflection calculation is introduced in a ray tracing context. The information from a hemispherical sampling of the luminous environment is interpreted in a new way to predict the change in irradiance as a function of position and surface orientation. The additional computation involved is modest and the benefit is substantial. An improved interpolation of irradiance resulting from the gradient calculation produces smoother, more accurate renderings. This result is achieved through better utilization of ray samples rather than additional samples or alternate sampling strategies. Thus, the technique is applicable to a variety of global illumination algorithms that use hemicubes or Monte Carlo sampling techniques

  20. Microwave Irradiation

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 5; Issue 3. Microwave Irradiation - Way to Eco-friendly, Green Chemistry. Rashmi Sanghi. General Article Volume 5 Issue 3 March 2000 pp 77-81. Fulltext. Click here to view fulltext PDF. Permanent link:

  1. Gonadal Irradiation

    African Journals Online (AJOL)

    division either by mitosis or meiosis show the least degree of radiation tolerance. This can be readily demonstrated histologically. Two hours after irradiation the spermatogenetic cell column starts to shrink because of a reduction in the number of spermatogonia, some of which are undergoing abnormal mitosis. Four days ...

  2. ion irradiation

    Indian Academy of Sciences (India)

    Swift heavy ions interact predominantly through inelastic scattering while traversing any polymer medium and produce excited/ionized atoms. Here samples of the polycarbonate Makrofol of approximate thickness 20 m, spin coated on GaAs substrate were irradiated with 50 MeV Li ion (+3 charge state). Build-in ...

  3. Microwave Irradiation

    Indian Academy of Sciences (India)

    Microwave Irradiation. Way to Eco-friendly, Green Chemistry. Rashmi Sanghi. This article highlights with examples, the usefulness of microwaves for carrying out a'variety of organic transfor- mations. Introduction and Background. The rapid heating of food in the kitchen using microwave ovens prompted a number of ...

  4. Principles of the prolactin/vasoinhibin axis.

    Science.gov (United States)

    Triebel, Jakob; Bertsch, Thomas; Bollheimer, Cornelius; Rios-Barrera, Daniel; Pearce, Christy F; Hüfner, Michael; Martínez de la Escalera, Gonzalo; Clapp, Carmen

    2015-11-15

    The hormonal family of vasoinhibins, which derive from the anterior pituitary hormone prolactin, are known for their inhibiting effects on blood vessel growth, vasopermeability, and vasodilation. As pleiotropic hormones, vasoinhibins act in multiple target organs and tissues. The generation, secretion, and regulation of vasoinhibins are embedded into the organizational principle of an axis, which integrates the hypothalamus, the pituitary, and the target tissue microenvironment. This axis is designated as the prolactin/vasoinhibin axis. Disturbances of the prolactin/vasoinhibin axis are associated with the pathogenesis of retinal and cardiac diseases and with diseases occurring during pregnancy. New phylogenetical, physiological, and clinical implications are discussed. Copyright © 2015 the American Physiological Society.

  5. Acute injuries of the axis vertebra

    Energy Technology Data Exchange (ETDEWEB)

    Burke, J.T. (United General Hospital, Sedro Woolley, WA (USA)); Harris, J.H. (Texas Univ., Houston, TX (USA). Dept. of Radiology)

    1989-08-01

    A retrospective analysis of 165 patients admitted to Hermann Hospital with acute injuries of the axis vertebra revealed 68 (41%) dens fractures, 62 (38%) cases of traumatic spondylolisthesis ('hangman's' fracture), 21 (13%) extension teardrop fractures, 10 (6%) hyperextension dislocations, and 2 (1.0%) fractures each of the laminae and spinous processes. Of the axis injuries 31 (18%) were limited to the axis body alone. Of these, 21 (61%) were hyperextension teardrop fractures and 10 (32%) were hyperextension dislocations. Axis injuries were associated with acute injuries of other cervical vertebrae in 14 (8%) of the patients. (orig./GDG).

  6. Food irradiation: An update

    International Nuclear Information System (INIS)

    Morrison, Rosanna M.

    1984-01-01

    Recent regulatory and commercial activity regarding food irradiation is highlighted. The effects of irradiation, used to kill insects and microorganisms which cause food spoilage, are discussed. Special attention is given to the current regulatory status of food irradiation in the USA; proposed FDA regulation regarding the use of irradiation; pending irradiation legislation in the US Congress; and industrial applications of irradiation

  7. Food irradiation

    International Nuclear Information System (INIS)

    Beerens, H.; Saint-Lebe, L.

    1979-01-01

    Various aspects of food treatment by cobalt 60 or caesium 137 gamma radiation are reviewed. One of the main applications of irradiation on foodstuffs lies in its ability to kill micro-organisms, lethal doses being all the lower as the organism concerned is more complex. The effect on parasites is also spectacular. Doses of 200 to 300 krad are recommended to destroy all parasites with no survival period and no resistance phenomenon has ever been observed. The action of gamma radiation on macromolecules was also investigated, the bactericide treatment giving rise to side effects by transformation of food components. Three examples were studied: starch, nucleic acids and a whole food, the egg. The organoleptic aspect of irradiation was examined for different treated foods, then the physical transformations of unpasteurized, heat-pasteurized and radio-pasteurized eggs were compared. The report ends with a brief analysis of the toxicity and conditions of application of the treatment [fr

  8. Orientational acoustic emission induced by electrons moving near a crystallographic axis in tungsten

    International Nuclear Information System (INIS)

    Alejnik, A.N.; Vorob'ev, S.A.; Zabaev, V.N.; Il'in, S.I.; Kalinin, B.N.; Potylitsyn, A.P.

    1988-01-01

    The measurement results of oriented acoustic irradiation of electrons with E 0 =900 MeV energies during their axial (along the direction) motion in tungsten monocrystal of 0.29 mm thickness are presented. The model describing the excitation of elastic waves in crystals as the consequence of the momentum transferred to the crystal by electrons during their motion near the axis is suggested. The model describes quite fully main laws of oriented acoustic irradiation. It permits to receive the information about the potential of the atom chain

  9. Design of Off-Axis PIAACMC Mirrors

    Science.gov (United States)

    Pluzhnik, Eugene; Guyon, Olivier; Belikov, Ruslan; Kern, Brian; Bendek, Eduardo

    2015-01-01

    The Phase-Induced Amplitude Apodization Complex Mask Coronagraph (PIAACMC) provides an efficient way to control diffraction propagation effects caused by the central obstruction/segmented mirrors of the telescope. PIAACMC can be optimized in a way that takes into account both chromatic diffraction effects caused by the telescope obstructed aperture and tip/tilt sensitivity of the coronagraph. As a result, unlike classic PIAA, the PIAACMC mirror shapes are often slightly asymmetric even for an on-axis configuration and require more care in calculating off-axis shapes when an off-axis configuration is preferred. A method to design off-axis PIAA mirror shapes given an on-axis mirror design is presented. The algorithm is based on geometrical ray tracing and is able to calculate off-axis PIAA mirror shapes for an arbitrary geometry of the input and output beams. The method is demonstrated using the third generation PIAACMC design for WFIRST-AFTA (Wide Field Infrared Survey Telescope-Astrophysics Focused Telescope Assets) telescope. Geometrical optics design issues related to the off-axis diffraction propagation effects are also discussed.

  10. The field performance of a 558 kWp ground mounted single-axis PV system in Pretoria, South Africa

    CSIR Research Space (South Africa)

    Roro, Kitessa T

    2017-12-01

    Full Text Available in sunniest parts of the world where the direct normal irradiance (DNI) component of sunlight is relatively high. However, very few studies have been reported on the field performance of single axis tracking systems installed and operated in the Southern...

  11. A high speed vertical axis wind machine

    National Research Council Canada - National Science Library

    South, P

    1976-01-01

    The operational feasibility of vertical axis wind machines was investigated at the National Aeronautical Establishment in Ottawa through use of a wind tunnel and a rotor with blades curved in a skipping rope shape...

  12. UMAPRM: Uniformly sampling the medial axis

    KAUST Repository

    Yeh, Hsin-Yi Cindy

    2014-05-01

    © 2014 IEEE. Maintaining clearance, or distance from obstacles, is a vital component of successful motion planning algorithms. Maintaining high clearance often creates safer paths for robots. Contemporary sampling-based planning algorithms That utilize The medial axis, or The set of all points equidistant To Two or more obstacles, produce higher clearance paths. However, They are biased heavily Toward certain portions of The medial axis, sometimes ignoring parts critical To planning, e.g., specific Types of narrow passages. We introduce Uniform Medial Axis Probabilistic RoadMap (UMAPRM), a novel planning variant That generates samples uniformly on The medial axis of The free portion of Cspace. We Theoretically analyze The distribution generated by UMAPRM and show its uniformity. Our results show That UMAPRM\\'s distribution of samples along The medial axis is not only uniform but also preferable To other medial axis samplers in certain planning problems. We demonstrate That UMAPRM has negligible computational overhead over other sampling Techniques and can solve problems The others could not, e.g., a bug Trap. Finally, we demonstrate UMAPRM successfully generates higher clearance paths in The examples.

  13. Actuator assembly including a single axis of rotation locking member

    Science.gov (United States)

    Quitmeyer, James N.; Benson, Dwayne M.; Geck, Kellan P.

    2009-12-08

    An actuator assembly including an actuator housing assembly and a single axis of rotation locking member fixedly attached to a portion of the actuator housing assembly and an external mounting structure. The single axis of rotation locking member restricting rotational movement of the actuator housing assembly about at least one axis. The single axis of rotation locking member is coupled at a first end to the actuator housing assembly about a Y axis and at a 90.degree. angle to an X and Z axis providing rotation of the actuator housing assembly about the Y axis. The single axis of rotation locking member is coupled at a second end to a mounting structure, and more particularly a mounting pin, about an X axis and at a 90.degree. angle to a Y and Z axis providing rotation of the actuator housing assembly about the X axis. The actuator assembly is thereby restricted from rotation about the Z axis.

  14. Anisotropic electrical conductivity in quartz during γ-irradiation

    International Nuclear Information System (INIS)

    Miyazaki, T.; Kato, N.; Fueki, K.; Ohshima, N.

    1989-01-01

    Electrical conductivity of quartz during γ-irradiation has been studied at 295Κ. A significant electric current was observed in z-cut quartz, but it could not be measured at all in x-cut quartz, y-cut quartz, and amorphous silica. The mobile ionic species produced during γ-irradiation migrate efficiently along the c axis of a quartz crystal. The G value (i.e., the number of product molecules (or ions) formed on irradiations per 100 eV of energy absorbed) of the mobile free ions was determined to be 0.018 from the field dependence of current at low dose rates

  15. Stimuli-Driven Control of the Helical Axis of Self-Organized Soft Helical Superstructures.

    Science.gov (United States)

    Bisoyi, Hari Krishna; Bunning, Timothy J; Li, Quan

    2018-03-30

    Supramolecular and macromolecular functional helical superstructures are ubiquitous in nature and display an impressive catalog of intriguing and elegant properties and performances. In materials science, self-organized soft helical superstructures, i.e., cholesteric liquid crystals (CLCs), serve as model systems toward the understanding of morphology- and orientation-dependent properties of supramolecular dynamic helical architectures and their potential for technological applications. Moreover, most of the fascinating device applications of CLCs are primarily determined by different orientations of the helical axis. Here, the control of the helical axis orientation of CLCs and its dynamic switching in two and three dimensions using different external stimuli are summarized. Electric-field-, magnetic-field-, and light-irradiation-driven orientation control and reorientation of the helical axis of CLCs are described and highlighted. Different techniques and strategies developed to achieve a uniform lying helix structure are explored. Helical axis control in recently developed heliconical cholesteric systems is examined. The control of the helical axis orientation in spherical geometries such as microdroplets and microshells fabricated from these enticing photonic fluids is also explored. Future challenges and opportunities in this exciting area involving anisotropic chiral liquids are then discussed. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Aeroelastically coupled blades for vertical axis wind turbines

    Science.gov (United States)

    Paquette, Joshua; Barone, Matthew F.

    2016-02-23

    Various technologies described herein pertain to a vertical axis wind turbine blade configured to rotate about a rotation axis. The vertical axis wind turbine blade includes at least an attachment segment, a rear swept segment, and optionally, a forward swept segment. The attachment segment is contiguous with the forward swept segment, and the forward swept segment is contiguous with the rear swept segment. The attachment segment includes a first portion of a centroid axis, the forward swept segment includes a second portion of the centroid axis, and the rear swept segment includes a third portion of the centroid axis. The second portion of the centroid axis is angularly displaced ahead of the first portion of the centroid axis and the third portion of the centroid axis is angularly displaced behind the first portion of the centroid axis in the direction of rotation about the rotation axis.

  17. Device to irradiate agricultural product on the production site, after harvesting

    International Nuclear Information System (INIS)

    Jegu, Jean; Palomo, Georges; Blaive, Daniel.

    1982-01-01

    The invention concerns a device to irradiate agricultural product on the production site, after harvesting. It includes an outer shielding to absorb the radiations and containers in which the products are placed for irradiation. The shielding is rotationally symmetrical around a vertical axis and holds an irradiation chamber containing a radioactive bar fitted along the shielding axis. The cylindrical containers are placed around the chamber with their axes parallel to the axis of the shielding. They are set in rotation by a motor and receive the farm products through their top ends which communicate with a supply system. Their bottom ends are closed by shutters covering a means for evacuating the products. The invention applies in particular to the irradiation of newly dug potatoes to avoid germination [fr

  18. Irradiation Facilities at CERN

    CERN Document Server

    Gkotse, Blerina; Carbonez, Pierre; Danzeca, Salvatore; Fabich, Adrian; Garcia, Alia, Ruben; Glaser, Maurice; Gorine, Georgi; Jaekel, Martin, Richard; Mateu,Suau, Isidre; Pezzullo, Giuseppe; Pozzi, Fabio; Ravotti, Federico; Silari, Marco; Tali, Maris

    2017-01-01

    CERN provides unique irradiation facilities for applications in many scientific fields. This paper summarizes the facilities currently operating for proton, gamma, mixed-field and electron irradiations, including their main usage, characteristics and information about their operation. The new CERN irradiation facilities database is also presented. This includes not only CERN facilities but also irradiation facilities available worldwide.

  19. Theoretical tool movement required to diamond turn an off-axis paraboloid on axis

    International Nuclear Information System (INIS)

    Thompson, D.C.

    1976-01-01

    Current techniques for manufacturing off-axis paraboloids are both expensive and insufficiently accurate. An alternative method, turning the workpiece about its axis on a diamond-turning machine, is presented, and the equations describing the necessary tool movement are derived. A discussion of a particular case suggests that the proposed technique is feasible

  20. Perspective on food irradiation

    International Nuclear Information System (INIS)

    Newsome, R.L.

    1987-01-01

    A brief review summarizes current scientific information on the safety and efficacy of irradiation processing of foods. Attention is focused on: specifics of the irradiation process and its effectiveness in food preservation; the historical development of food irradiation technology in the US; the response of the Institute of Food Technologists to proposed FDA guidelines for food irradiation; the potential uses of irradiation in the US food industry; and the findings of the absence of toxins and of unaltered nutrient density (except possibly for fats) in irradiated foods. The misconceptions of consumers concerning perceived hazards associated with food irradiation, as related to consumer acceptance, also are addressed

  1. Food irradiation in Britain

    International Nuclear Information System (INIS)

    Webb, T.

    1985-01-01

    This report explains the process and issues that concern consumers, workers in the food industry and people involved in food policy, public health and environmental protection. It argues that safety assurances by experts are not enough, and calls for a full public debate on all issues surrounding food irradiation, including a) wholesomeness of irradiated foods - food quality, nutrition losses, chemical and other changes in irradiated foods b) consumers rights to information about irradiated foods c) health and safety of food industry workers d) the economics of irradiation - food prices, changes in patters of employment, environmental impacts e) regulation and monitoring of food irradiation and imported irradiated foods. (U.K.)

  2. Modular off-axis solar concentrator

    Science.gov (United States)

    Plesniak, Adam P; Hall, John C

    2015-01-27

    A solar concentrator including a housing defining a vertical axis and including a receiving wall connected to a reflecting wall to define an internal volume and an opening into the internal volume, wherein the reflecting wall defines at least one primary optical element, and wherein at least a portion of the reflecting wall includes a layer of reflective material, the housing further including a cover connected to the receiving wall and the reflecting wall to seal the opening, and at least one receiver mounted on the receiving wall such that a vertical axis of the receiver is disposed at a non-zero angle relative to the vertical axis of the housing, the receiver including at least one photovoltaic cell.

  3. Enclosed, off-axis solar concentrator

    Science.gov (United States)

    Benitez, Pablo; Grip, Robert E; Minano, Juan C; Narayanan, Authi A; Plesniak, Adam; Schwartz, Joel A

    2013-11-26

    A solar concentrator including a housing having receiving wall, a reflecting wall and at least two end walls, the receiving, reflecting and end walls defining a three-dimensional volume having an inlet, wherein a vertical axis of the housing is generally perpendicular to the inlet, a receiver mounted on the receiving wall of the housing, the receiver including at least one photovoltaic cell, wherein a vertical axis of the receiver is disposed at a non-zero angle relative to the vertical axis of the housing, at least one clip disposed on the reflecting wall an optical element received within the three-dimensional volume, the optical element including at least one tab, the tab being engaged by the clip to align the optical element with the receiver, and a window received over the inlet to enclose the housing.

  4. Innovative Design of Vertical Axis Wind Turbine

    DEFF Research Database (Denmark)

    Chougule, Prasad

    2013-01-01

    The wind turbines can be classified as: i) Horizontal axis wind turbines (HAWT), and ii) Vertical axis wind turbines (VAWT). The HAWT is fully developed and the size is growing higher. Whereas, the VAWT is not developed because of the less efficiency and vibration issues of big structure. However......, and its aerodynamic characteristics are obtained by an experimental method. A new design is called D2퐴 − 푉퐴푊푇 and a test ring is made to validate the numerical results. A double multiple stream tube method (DMSTM) and blade element method (BEM) are used to determine the numerical performance of a proposed...

  5. Medulloblastoma subgroup-specific outcomes in irradiated children: who are the true high-risk patients?

    Science.gov (United States)

    Ramaswamy, Vijay; Remke, Marc; Adamski, Jennifer; Bartels, Ute; Tabori, Uri; Wang, Xin; Huang, Annie; Hawkins, Cynthia; Mabbott, Donald; Laperriere, Normand; Taylor, Michael D; Bouffet, Eric

    2016-02-01

    The advent of integrated genomics has fundamentally changed our understanding of medulloblastoma. Although survival differences exist among the 4 principal subgroups, this has yet to be elucidated in a North American cohort of irradiated patients. Ninety-two consecutive patients between the ages of 3 and 17 treated with surgery, craniospinal irradiation, and chemotherapy were identified at the Hospital for Sick Children. Molecular subgrouping was performed using nanoString. Two treatment periods were identified: prior to 2006 as per the protocols of the Children's Oncology Group, and after 2006 per the St Jude Medulloblastoma 03 protocol. Five-year progression-free survival (PFS) over the entire cohort was 0.801 (95% CI: 0.692-0.875) with no significant difference between treatment protocols. Strikingly, we found that Group 4 patients had excellent 5-year PFS of 0.959 (95% CI: 0.744-0.994) for average risk and 0.887 (95% CI: 0.727-0.956) across all Group 4 patients. Group 3 patients had 5-year PFS of 0.733 (95% CI: 0.436-0.891). Sonic hedgehog patients did poorly across both treatment protocols, with 5-year PFS of 0.613 (95% CI: 0.333-0.804), likely owing to a high proportion of TP53 mutated patients in this age group. In a cohort of irradiated patients over 3 years of age, PFS for Group 4 patients was significantly improved compared with initial reports. The impact of subgroup affiliation in these children needs to be assessed in large prospectively treated cooperative protocols to determine if more than just WNT patients can be safely selected for de-escalation of therapy. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Research of misalignment between dithered ring laser gyro angle rate input axis and dither axis

    Science.gov (United States)

    Li, Geng; Wu, Wenqi; FAN, Zhenfang; LU, Guangfeng; Hu, Shaomin; Luo, Hui; Long, Xingwu

    2014-12-01

    The strap-down inertial navigation system (SINS), especially the SINS composed by dithered ring laser gyroscope (DRLG) is a kind of equipment, which providing high reliability and performance for moving vehicles. However, the mechanical dither which is used to eliminate the "Lock-In" effect can cause vibration disturbance to the INS and lead to dithering coupling problem in the inertial measurement unit (IMU) gyroscope triad, so its further application is limited. Among DRLG errors between the true gyro rotation rate and the measured rotation rate, the frequently considered one is the input axis misalignment between input reference axis which is perpendicular to the mounting surface and gyro angular rate input axis. But the misalignment angle between DRLG dither axis and gyro angular rate input axis is often ignored by researchers, which is amplified by dither coupling problem and that would lead to negative effects especially in high accuracy SINS. In order to study the problem more clearly, the concept of misalignment between DRLG dither axis and gyro angle rate input axis is researched. Considering the error of misalignment is of the order of 10-3 rad. or even smaller, the best way to measure it is using DRLG itself by means of an angle exciter as an auxiliary. In this paper, the concept of dither axis misalignment is explained explicitly firstly, based on this, the frequency of angle exciter is induced as reference parameter, when DRLG is mounted on the angle exciter in a certain angle, the projections of angle exciter rotation rate and mechanical oscillation rate on the gyro input axis are both sensed by DRLG. If the dither axis has misalignment error with the gyro input axis, there will be four major frequencies detected: the frequency of angle exciter, the dither mechanical frequency, sum and difference frequencies of the former two frequencies. Then the amplitude spectrum of DRLG output signal obtained by the using LabVIEW program. if there are only angle

  7. Triple-axis spectrometer DruechaL

    International Nuclear Information System (INIS)

    Buehrer, W.; Keller, P.

    1996-01-01

    DruechaL is a triple-axis spectrometer located at a cold guide. The characteristics of guide and instrument allow the use of a broad spectral range of neutrons. The resolution in momentum and energy transfer can be tuned to match the experimental requirements by using either collimators or focusing systems (monochromator, antitrumpet, analyser). (author) figs., tabs., refs

  8. Triple-axis spectrometer DruechaL

    Energy Technology Data Exchange (ETDEWEB)

    Buehrer, W.; Keller, P. [Lab. for Neutron Scattering ETH Zurich, Zurich (Switzerland) and Paul Scherrer Institute, Villigen (Switzerland)

    1996-11-01

    DruechaL is a triple-axis spectrometer located at a cold guide. The characteristics of guide and instrument allow the use of a broad spectral range of neutrons. The resolution in momentum and energy transfer can be tuned to match the experimental requirements by using either collimators or focusing systems (monochromator, antitrumpet, analyser). (author) figs., tabs., refs.

  9. Microbes and the gut-brain axis.

    Science.gov (United States)

    Bercik, P; Collins, S M; Verdu, E F

    2012-05-01

    The 'gut-brain' or 'brain-gut axis', depending on whether we emphasize bottom-up or top-bottom pathways, is a bi-directional communication system, comprised of neural pathways, such as the enteric nervous system (ENS), vagus, sympathetic and spinal nerves, and humoral pathways, which include cytokines, hormones, and neuropeptides as signaling molecules. Recent evidence, mainly arising from animal models, supports a role of microbes as signaling components in the gut-brain axis. The purpose of this review is to summarize our current knowledge regarding the role of microbes, including commensals, probiotics and gastrointestinal pathogens, in bottom-up pathways of communication in the gut-brain axis. Although this has clear implications for psychiatric co-morbidity in functional and inflammatory conditions of the gut, the focus of this review will be to discuss the current evidence for a role of bacteria (commensals, probiotics, and pathogens) as key modulators of gut-brain communication. The strongest evidence for a role of microbes as signaling components in the gut-brain axis currently arises from animal studies and indicate that mechanisms of communication are likely to be multiple. There is need for the concepts generated in animal models to be translated to the human in the future. © 2012 Blackwell Publishing Ltd.

  10. The Trading Axis in Irkutsk Downtown

    Directory of Open Access Journals (Sweden)

    Elena Grigoryeva

    2016-10-01

    Full Text Available The article reveals a linear concentration of the trading function in the historical center of Irkutsk. It features historical prerequisites and continuation of the tradition in the post-Soviet period, given the conversion of plants and factories. The article analyses the current state and prospects of modernization of the trading axis with its transformation into a modern public space.

  11. Mechanical axis-derived femoral component rotation in extramedullary total knee arthroplasty: a comparison between femoral transverse axis and transepicondylar axis.

    Science.gov (United States)

    Seo, Jai-Gon; Moon, Young-Wan; Lim, Ji-Soon; Park, Se-Jun; Kim, Sang-Min

    2012-03-01

    Correct rotational alignment of the femoral component is paramount to the success of total knee arthroplasty, but debate continues as to which method is the most reliable. The purpose of this study was to evaluate mechanical axis-derived rotational axis of the femoral component using an extramedullary femoral alignment guide system. Between 2009 and 2010, 60 patients (120 knees) underwent simultaneous bilateral total knee arthroplasty. Postoperative CT scans were performed on all 120 knees. The mechanical axis-derived rotational axis of the femoral component was compared with the surgical transepicondylar axis on CT scans. The femoral component was externally rotated compared with the surgical transepicondylar axis (mean = 1.6°, SD = 2.2°, range: from 4.8° of internal rotation to 7.9° of external rotation). One hundred and nine of the 120 knees (90.8%) were rotated by less than 5° from the surgical transepicondylar axis. All inter-observer observations on CT scans were within a range of ±2.1° and showed no significant differences. Mechanical axis-derived rotational axis of the femoral component was found to be closely related to the surgical transepicondylar axis, to an extent which suggests that the mechanical axis-derived rotational axis could be a new alternative option in determining optimal rotational alignment of the femoral component during total knee arthroplasty. II.

  12. UARS PEM Level 2 AXIS 2 V001 (UARPE2AXIS2) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — The UARS Particle Environment Monitor (PEM) level 2 Atmosphere X-Ray Imaging Spectrometer (AXIS) unit 2 daily product contains the X-ray high-resolution spectral...

  13. UARS PEM Level 2 AXIS 1 V001 (UARPE2AXIS1) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — The UARS Particle Environment Monitor (PEM) level 2 Atmosphere X-Ray Imaging Spectrometer (AXIS) unit 1 daily product contains the X-ray high-resolution spectral...

  14. Facts about food irradiation: Food irradiation costs

    International Nuclear Information System (INIS)

    1991-01-01

    This fact sheet gives the cost of a typical food irradiation facility (US $1 million to US $3 million) and of the food irradiation process (US $10-15 per tonne for low-dose applications; US $100-250 per tonne for high-dose applications). These treatments also bring consumer benefits in terms of availability, storage life and improved hygiene. 2 refs

  15. Evaluation of the angles of magnetic axis relative to rotation axis of pulsars

    International Nuclear Information System (INIS)

    Kuz'min, A.D.; Dagkesamanskaya, I.M.

    1983-01-01

    The difference of an observed width of integrated pulse's profile and a beamwidth of pulsar emission is pointed out. A method to evaluate angle #betta# of the magnetic axis relative to the rotation axis is proposed. Values of #betta# are obtained for 308 pulsars. The secular decrease of #betta# has been found. The radius of the emitting region, #betta#-factors and the density of radiating particles are also evaluated

  16. Food irradiation in China

    International Nuclear Information System (INIS)

    Zhu Jiang

    1994-01-01

    In this paper, the author discussed the recent situation of food irradiation in China, its history, facilities, clearance, commercialization, and with emphasis on market testing and public acceptance of irradiated food. (author)

  17. Food irradiation makes progress

    International Nuclear Information System (INIS)

    Kooij, J. van

    1984-01-01

    In the past fifteen years, food irradiation processing policies and programmes have been developed both by a number of individual countries, and through projects supported by FAO, IAEA and WHO. These aim at achieving general acceptance and practical implementation of food irradiation through rigorous investigations of its wholesomeness, technological and economic feasibility, and efforts to achieve the unimpeded movement of irradiated foods in international trade. Food irradiation processing has many uses

  18. JMTR irradiation handbook

    International Nuclear Information System (INIS)

    1994-03-01

    A wide variety of nuclear irradiation and post-irradiation experiments are available using the Japan Materials Testing Reactor, 50 MW (JMTR) and the multi-cell hot laboratory associated with the JMTR. In this Handbook, an application manual for conducting irradiation and post-irradiation experiments using those facilities is provided. The Handbook is primarily designed to aid the experimenter and to serve as a reference for communications between the experimenter and the Department of JMTR Project. (author)

  19. Design of POTON irradiator

    International Nuclear Information System (INIS)

    Hans, R.P.; Modi, R.K.; Ramakumar, M.S.

    1997-01-01

    Clearance by Government of India, for irradiating various food items, to increase either its shelf life or for reducing post harvest losses, has opened up a challenge for designing a multi-product, high throughput and a reliable commercial food irradiator. Various design aspects of mechanical system for such type of commercial food irradiator i.e. POTON irradiator for potatoes and onions, are presented here. (author). 3 refs., 2 figs

  20. Dosimetry for Crystals Irradiation

    CERN Document Server

    Lecomte, Pierre

    2005-01-01

    Before shipment to CMS, all PbWO4 crystals produced in China are irradiated there with 60 Co , in order to insure that the induced absorption coefficient is within specifications. Acceptance tests at CERNand at ENEA also include irradiation with gamma rays from 60 Co sources. There were initially discrepancies in quoted doses and doserates as well as in induced absorption coefficients. The present work resolves the discrepancies in irradiation measurements and defines common dosimetry methods for consistency checks between irradiation facilities.

  1. A Portable Single Axis Magnetic Gradiometer

    DEFF Research Database (Denmark)

    Merayo, José M.G.; Petersen, Jan Raagaard; Nielsen, Otto V

    2001-01-01

    The single axis magnetic gradiometer based on two compact detector compensation (CDC) fluxgate ringcore sensors separated 20 cm is described. Despite its high stability and precision better than 1 nT, the calibration procedures are not straightforward. Firstly, the mono-axial measurement does not...... measurements is achieved by using a magnetic dipole of strength 2 mAm(2). In a coil facility, the gradient can be determined with an accuracy of 0.3 nT/m(RMS)....

  2. Resolution of a triple axis spectrometer

    DEFF Research Database (Denmark)

    Nielsen, Mourits; Bjerrum Møller, Hans

    1969-01-01

    A new method for obtaining the resolution function for a triple-axis neutron spectrometer is described, involving a combination of direct measurement and analytical calculation. All factors which contribute to the finite resolution of the instrument may be taken into account, and Gaussian...... or experimentally determined probability distributions may be used. The application to the study of the dispersion relation for excitations in a crystal is outlined...

  3. AXIS - Advanced X-ray Imaging Sarellite

    Science.gov (United States)

    Loewenstein, Michael; AXIS Team

    2018-01-01

    We present an overview of the Advanced X-ray Imaging Satellite (AXIS), a probe mission concept under study to the 2020 Decadal survey. AXIS follows in the footsteps of the spectacularly successful Chandra X-ray Observatory with similar or higher angular resolution and an order of magnitude more collecting area in the 0.3-10 keV band over a 15' field of view. These capabilities are designed to attain a wide range of science goals such as (i) measuring the event horizon scale structure in AGN accretion disks and the spin of supermassive black holes through monitoring of gravitationally microlensed quasars; (ii) understanding AGN and starburst feedback in galaxies and galaxy clusters through direct imaging of winds and interaction of jets and via spatially resolved imaging of galaxies at high-z; (iii) probing the fueling of AGN by resolving the SMBH sphere of influence in nearby galaxies; (iv) investigating hierarchical structure formation and the SMBH merger rate through measurement of the occurrence rate of dual AGN and occupation fraction of SMBHs; (v) advancing SNR physics and galaxy ecology through large detailed samples of SNR in nearby galaxies; (vi) measuring the Cosmic Web through its connection to cluster outskirts. With a nominal 2028 launch, AXIS benefits from natural synergies with LSST, ELTs, ALMA, WFIRST and ATHENA, and will be a valuable precursor to Lynx. AXIS utilizes breakthroughs in the construction of light-weight X-ray optics from mono-crystalline silicon blocks, and developments in the fabrication of large format, small pixel, high readout detectors.

  4. Containers in food irradiation

    International Nuclear Information System (INIS)

    Bolumen, S.; Espinosa, R.

    1997-01-01

    The preservation of food by irradiation is promising technology which increases industrial application. Packaging of irradiated foods is an integral part of the process. Judicious selection of the package material for successful trade is essential. In this paper is presented a brief review of important aspects of packaging in food irradiation [es

  5. Irradiation of foodstuffs

    International Nuclear Information System (INIS)

    Sjoeberg, A.M.

    1993-01-01

    Foodstuffs are irradiated to make them keep better. The ionizing radiation is not so strong as to cause radioactivity in the foodstuffs. At least so far, irradiation has not gained acceptance among consumers, although it has been shown to be a completely safe method of preservation. Irradiation causes only slight chemical changes in food. What irradiation does, however, is to damage living organisms, such as bacteria, DNA and proteins, thereby making the food keep longer. Irradiation can be detected from the food afterwards; thus it can be controlled effectively. (orig.)

  6. A device for external γ-irradiation of experimental animals

    International Nuclear Information System (INIS)

    Ivanitskaya, N.F.; Talakin, Yu.N.; Lekakh, V.A.

    1992-01-01

    A device was developed for external gamma-irradiation of experimental animals including a radiation source, a device for fixation of the total animal or a segment of its body in the focus of irradiation, and a shilding screen. To widen the sphere of this device application by making possible a simultaneous radiation exposure of a group of animals under various radiation schedules, the device involves two discs with a common axis. The lower disc is provided with an electric drive and containers with animals are placed on it, and the upper disc is for the shielding screen. The device is supplied with an operation block

  7. Theoretical tool movement required to diamond turn an off-axis paraboloid on axis

    International Nuclear Information System (INIS)

    Thompson, D.C.

    1975-01-01

    High-quality, off-axis parabolic reflectors, required by the CTR and laser-fusion programs at Lawrence Livermore Laboratory (LLL) and other ERDA laboratories, are currently manufactured by hand. There are several drawbacks to this method, including lead times of up to a year, costs in excess of dollars 75,000 for a small reflector, and unsatisfactory limits to the tolerances obtainable. This situation has led to a search for cheaper and more accurate methods of manufacturing off-axis paraboloids. An alternative method, turning the workpiece about its axis on a diamond-turning machine, is presented, and the equations describing the necessary tool movement are derived. A discussion of a particular case suggests that the proposed technique is feasible

  8. The Triple Axis and SPINS Spectrometers.

    Science.gov (United States)

    Trevino, S F

    1993-01-01

    In this paper are described the triple axis and spin polarized inelastic neutron scattering (SPINS) spectrometers which are installed at the NIST Cold Neutron Research Facility (CNRF). The general principle of operation of these two instruments is described in sufficient detail to allow the reader to make an informed decision as to their usefulness for his needs. However, it is the intention of the staff at the CNRF to provide the expert resources for their efficient use in any given situation. Thus, this work is not intended as a user manual but rather as a guide into the range of applicability of the two instruments.

  9. The triple axis and SPINS spectrometers

    International Nuclear Information System (INIS)

    Trevino, S.F.

    1993-01-01

    In this paper are described the triple axis and spin polarized inelastic neutron scattering (SPINS) spectrometers which are installed at the NIST Cold Neutron Research Facility (CNRF). The general principle of operation of these two instruments is described in sufficient detail to allow the reader to make an informed decision as to their usefulness for his needs. However, it is the intention of the staff at the CNRF to provide the expert resources for their efficient use in any given situation. Thus, this work is not intended as a user manual but rather as a guide into the range of applicability of the two instruments

  10. Sensory properties of irradiated foods

    International Nuclear Information System (INIS)

    Plestenjak, A.

    1997-01-01

    Food irradiation is a simple and effective preservation technique. The changes caused by irradiation depend on composition of food, on the absorbed dose, the water content and temperature during and after irradiation. In this paper the changes of food components caused by irradiation, doses for various food irradiation treatments, foods and countries where the irradiation is allowed, and sensory properties of irradiated food are reviewed

  11. Methamphetamine and the hypothalamic-pituitary-adrenal axis

    Directory of Open Access Journals (Sweden)

    Damian Gabriel Zuloaga

    2015-05-01

    Full Text Available Psychostimulants such as methamphetamine (MA induce significant alterations in the function of the hypothalamic-pituitary-adrenal (HPA axis. These changes in HPA axis function are associated with altered stress-related behaviors and might contribute to addictive processes such as relapse. In this mini-review we discuss acute and chronic effects of MA (adult and developmental exposure on the HPA axis, including effects on HPA axis associated genes/proteins, brain regions, and behaviors such as anxiety and depression. A better understanding of the mechanisms through which MA affects the HPA axis may lead to more effective treatment strategies for MA addiction.

  12. VERITAS: Versatile Triple-Axis Spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sung Il

    2006-04-15

    Korea Atomic Energy Research Institute is planning to build a cold neutron triple-axis spectrometer at HANARO, the 30 MW research reactor. The spectrometer is expected to be completed in 2008 with the following configuration from the upstream to the downstream. Guide Supermirror m = 2, In-pile Straight Section, {approx} 5 m Curved Guide, {approx} 26 m w/ R 1500 m Straight Guide before the Instrument, {approx} 40 m Filters PG and Be Neutron Velocity Selector (Future) Monochromators Vertically Focusing Monochromators PG(002) and Heusler(111) Doubly Focusing Monochromators (Future) Monochromator-Sample Distance 2 m Collimation C1 Soller Collimators, 20', 40' 80'Beam Height at the Sample Table 1.5 m Sample-Analyzer Distance 1.0 m Collimation C2 Soller Collimators, 20', 40', 80' Radial Collimator Analyzers Horizontally Focusing Analyzers w/ Fixed Vertical Focusing PG(002) and Heusler(111) Analyzer-Detector Distance 0.5 m Detectors 5 cm Tube Detector 25 cm wide Position Sensitive Detector Once completed, the neutron flux at sample is expected to surpass that of SPINS at NCNR, making this instrument one of the most powerful 2nd generation cold neutron triple-axis spectrometers in the world.

  13. VERITAS: Versatile Triple-Axis Spectrometer

    International Nuclear Information System (INIS)

    Park, Sung Il

    2006-04-01

    Korea Atomic Energy Research Institute is planning to build a cold neutron triple-axis spectrometer at HANARO, the 30 MW research reactor. The spectrometer is expected to be completed in 2008 with the following configuration from the upstream to the downstream. Guide Supermirror m = 2, In-pile Straight Section, ∼ 5 m Curved Guide, ∼ 26 m w/ R 1500 m Straight Guide before the Instrument, ∼ 40 m Filters PG and Be Neutron Velocity Selector (Future) Monochromators Vertically Focusing Monochromators PG(002) and Heusler(111) Doubly Focusing Monochromators (Future) Monochromator-Sample Distance 2 m Collimation C1 Soller Collimators, 20', 40' 80'Beam Height at the Sample Table 1.5 m Sample-Analyzer Distance 1.0 m Collimation C2 Soller Collimators, 20', 40', 80' Radial Collimator Analyzers Horizontally Focusing Analyzers w/ Fixed Vertical Focusing PG(002) and Heusler(111) Analyzer-Detector Distance 0.5 m Detectors 5 cm Tube Detector 25 cm wide Position Sensitive Detector Once completed, the neutron flux at sample is expected to surpass that of SPINS at NCNR, making this instrument one of the most powerful 2nd generation cold neutron triple-axis spectrometers in the world

  14. Debate on food irradiation

    International Nuclear Information System (INIS)

    1990-01-01

    An amendment moved on the food safety bill provided that any regulations made which relate to irradiation shall only be made after a diagnostic test has been established to determine whether or not food has been subject to irradiation and also that a scientific review has been conducted into the effects of irradiation on pesticide residues and other toxins in food, vitamin content of food, food additives and food packaging materials, and the results thereof published. The debate which followed lasted an hour and a quarter and is reported verbatim. After a short definition of irradiation, the debate was concerned with the nutritional value of irradiated food, the radiation effects for the public, the dose levels which are safe to use, public opinion and the lack of research into the effects of irradiating food. The amendment was withdrawn after the debate. (UK)

  15. Performance study on the east-west oriented single-axis tracked panel

    International Nuclear Information System (INIS)

    Chang, Tian Pau

    2009-01-01

    A theoretical study on the performance of an east-west oriented single-axis tracked panel was originally proposed in this paper. Mathematic expressions applicable for calculating the angle that the tracked panel should rotate by to follow the Sun are derived. The incident angle of sunlight upon the panel as well as the instantaneous increments of solar energy captured by the panel relative to a fixed horizontal surface are then demonstrated graphically. To simulate different operation environments, three kinds of radiation sources will be considered, i.e. the extraterrestrial radiation, global radiation predicted by empirical models under clear sky situation and global radiation observed in Taiwan. Simulation results show that the yearly gains correlate positively with the radiation level, i.e. 21.2%, 13.5% and 7.4% for the extraterrestrial, predicted and observed radiations, respectively, which are far less than those obtained from a north-south oriented single-axis tracked panel. The irradiation increases with the maximum rotation angle of the panel, the benefit of increasing the rotation in overcast environment is not as good as in clear sky, for annual energy collection 45 o is recommended. The irradiation received decreases with latitude, but it has a greater gain in higher latitude zone.

  16. Irradiation - who needs it?

    International Nuclear Information System (INIS)

    Scoular, C.

    1994-01-01

    In this paper the public's attitudes to the irradiation of food to ensure it is bacteria free and to prolong shelf-life are considered. The need to label irradiated food and to educate the public about its implications are emphasised. The opinions of the large food retailers who maintain that high standards in food processing, hygiene and refrigeration eliminate the need for food irradiation are discussed. (UK)

  17. Update on irradiation

    International Nuclear Information System (INIS)

    Wilkinson, Vanessa; Kilcast, David

    1988-01-01

    The authors summarize for the food manufacturing industries, the present legal situation and state of the art in the E.E.C., and immediate outlook in the U.K. in relation to food irradiation. They describe in outline the technology of irradiation and its potential in insect and microorganism control, with particular reference to combination processes, labelling, irradiation facilities, and changes in food components. (U.K.)

  18. Irradiation of food

    International Nuclear Information System (INIS)

    Lindell, B.; Danielsson-Tham, M.L.; Hoel, C.

    1983-01-01

    A committee has on instructions from the swedish government made an inquiry into the possible effects on health and working environment from irradition of food. In this report, a review is presented on the known positiv and negative effects of food irradiation Costs, availabilty, shelf life and quality of irradiated food are also discussed. According to the report, the production of radiolysis products during irradiation is not easily evaluated. The health risks from irradiation of spices are estimated to be lower than the risks associated with the ethenoxid treatment presently used. (L.E.)

  19. Gamma irradiation devices

    International Nuclear Information System (INIS)

    Foeldiak, Gabor; Stenger, Vilmos.

    1983-01-01

    The main parameters and the preparation procedures of the gamma radiation sources frequently applied for irradiation purposes are discussed. In addition to 60 Co and 137 Cs sources also the nuclear power plants offer further opportunities: spent fuel elements and products of certain (n,γ) reactions can serve as irradiation sources. Laboratory scale equipments, pilot plant facilities for batch or continuous operation, continuous industrial irradiators and special multipurpose, mobile and panorama type facilities are reviewed including those in Canada, USA, India, the Soviet Union, Hungary, UK, Japan and Australia. For irradiator design the source geometry dependence of the spatial distribution of dose rates can be calculated. (V.N.)

  20. Food irradiation: fiction and reality

    International Nuclear Information System (INIS)

    1991-01-01

    The International Consultative Group on Food Irradiation (IGCFI), sponsored by World Health Organization (WHO), Food and Agriculture Organization (FAO) and the International Atomic Energy Agency (IAEA), with the intention to provide to governments, especially those of developing countries, scientifically correct information about food irradiation, decided to organize a file and questions of general public interest. The document is composed by descriptive files related with the actual situation and future prospective, technical and scientific terms, food irradiation and the radioactivity, chemical transformations in irradiated food, genetic studies, microbiological safety of irradiated food, irradiation and harmlessness, irradiation and additives, packing, irradiation facilities control, process control, irradiation costs and benefits as well as consumers reaction

  1. Irradiation of the head, immediate effect on growth hormone secretion in children

    International Nuclear Information System (INIS)

    Dacou-Voutetakis, C.; Xypolyta, A.; Haidas, S.; Constantinidis, M.; Papavasiliou, C.; Zannos-Mariolea, L.

    1977-01-01

    Plasma growth hormone (GH) was determined in samples obtained hourly from 1000 h to 0700 h before, and after a 3 week course of ''prophylactic'' cranial irradiation, in ten leukemic children who had no clinical or laboratory evidence of central nervous system involvement. The mean per hour value of GH prior to irradiation (4.1 +- 2.4 ng/ml) was similar to that of 7 endocrinologically normal children (4.09 +- 2.4 ng/ml), a finding strongly suggesting normal pituitary function prior to irradiation. Following irradiation GH levels at each hour were, in general, lower than before. The difference is statistically significant at 0100h. The peak GH responses were lower following the preceding irradiation (p less than 0.02). The findings suggest an immediate suppressive effect of irradiation on the apparently normal hypothalamic pituitary axis in children

  2. New gas detector setup for on-axis STIM tomography experiments

    Energy Technology Data Exchange (ETDEWEB)

    Marques, A.C., E-mail: ana.marques@ctn.ist.utl.pt [IST/ITN, Instituto Superior Técnico, Universidade Técnica de Lisboa, Campus Tecnológico e Nuclear, E.N.10, 2686-953 Sacavém (Portugal); Centro de Física Nuclear da Universidade de Lisboa, Av. Prof. Gama Pinto 2, 1649-003 Lisboa (Portugal); Fraga, M.M.F.R. [Laboratório de Instrumentação e Física Experimental de Partículas, 3004-516 Coimbra (Portugal); Departamento de Física, Universidade de Coimbra, 3004-516 Coimbra (Portugal); Fonte, P. [Laboratório de Instrumentação e Física Experimental de Partículas, 3004-516 Coimbra (Portugal); Instituto Superior de Engenharia de Coimbra, 3030-199 Coimbra (Portugal); Beasley, D.G.; Alves, L.C.; Silva, R.C. da [IST/ITN, Instituto Superior Técnico, Universidade Técnica de Lisboa, Campus Tecnológico e Nuclear, E.N.10, 2686-953 Sacavém (Portugal); Centro de Física Nuclear da Universidade de Lisboa, Av. Prof. Gama Pinto 2, 1649-003 Lisboa (Portugal)

    2013-07-01

    A gas flow ionization chamber for use with on-axis scanning transmission ion microscopy tomography (STIM-T) has been developed. The entrance window is composed of a square silicon nitride membrane 100 nm thick and 1 mm{sup 2} in area. The use of this type of window does not add significantly to the energy resolution with the MeV H{sup +} or He{sup +} particles used in STIM, and proved to be resistant to high proton fluence in the irradiated spot. The ability of such detector to withstand direct beam hit with acceptable energy resolution makes it suitable for on-axis STIM-T, in this respect outperforming the more standard Si PIN diodes, which performance is known to degrade above fluences of ∼10{sup 10}–10{sup 12} cm{sup −2}. The present in-line design while allowing easy mounting of the detector to the existing target chamber, has the peculiarity of providing a practical way of replacing the Si{sub 3}N{sub 4} membrane in case it brakes while operating. The concept of gas ionization chamber under development is expected to become ideal for on-axis STIM-T experiments due to its low ageing during operation, and anticipated attainable speed and energy resolution.

  3. Modelling property changes in graphite irradiated at changing irradiation temperature

    CSIR Research Space (South Africa)

    Kok, S

    2011-01-01

    Full Text Available A new method is proposed to predict the irradiation induced property changes in nuclear; graphite, including the effect of a change in irradiation temperature. The currently used method; to account for changes in irradiation temperature, the scaled...

  4. RITA-type triple axis spectrometers

    International Nuclear Information System (INIS)

    Roennow, H.M.

    2001-01-01

    The RITA spectrometer at Risoe National Laboratory was the first to incorporate a complete re-thinking of the neutron-path from source, through detector to analysis. Since then, other RITA-type spectrometers such as SPINS at NIST, RITA-II at PSI have been built, and several new spectrometers around the world are adapting the same philosophy. The main novelty of RITA was the introduction of a single back-end tank featuring both an analyser block with multiple individually turnable analyser blades and a 2D position sensitive detector. Several new triple-axis spectrometers are presently being built at existing and future sources, and almost all of them have learnt from the experience with RITA. (R.P.)

  5. Polarized triple-axis spectrometer TASP

    Energy Technology Data Exchange (ETDEWEB)

    Boeni, P.; Keller, P. [Lab. for Neutron Scattering ETH Zurich, Zurich (Switzerland) and Paul Scherrer Institute, Villigen (Switzerland)

    1996-11-01

    The polarized triple-axis spectrometer TASP at SINQ has been optimized for measuring magnetic cross sections in condensed matter. The neutrons are polarized or analyzed either by means of benders or Heusler monochromators. The beam divergence, i.e. the intensity, and the spectral range of the neutrons is rather large because of the supermirror coatings of the feeding neutron guide. The intensity can be further increased at the sample position by means of a focussing monochromator and a focussing anti-trumpet. The end position of TASP allows the tailoring of the neutron beam already before the monochromator and to scatter neutrons over very wide ranges of angles. (author) 6 figs., 1 tab., 8 refs.

  6. Polarized triple-axis spectrometer TASP

    International Nuclear Information System (INIS)

    Boeni, P.; Keller, P.

    1996-01-01

    The polarized triple-axis spectrometer TASP at SINQ has been optimized for measuring magnetic cross sections in condensed matter. The neutrons are polarized or analyzed either by means of benders or Heusler monochromators. The beam divergence, i.e. the intensity, and the spectral range of the neutrons is rather large because of the supermirror coatings of the feeding neutron guide. The intensity can be further increased at the sample position by means of a focussing monochromator and a focussing anti-trumpet. The end position of TASP allows the tailoring of the neutron beam already before the monochromator and to scatter neutrons over very wide ranges of angles. (author) 6 figs., 1 tab., 8 refs

  7. Arterial thoracic vascularization in some deer species: pampas deer (Ozotoceros bezoarticus), brown brocket deer (Mazama gouazoubira) and axis deer (Axis axis).

    Science.gov (United States)

    Pérez, W; Erdoğan, S

    2014-12-01

    In this study, the arterial distributions of the aortic arches of three deer species (Axis axis, Ozotoceros bezoarticus and Mazama gouazoubira) were described. The animals were dissected immediately after being found dead. Latex injection method was used to observe the vascularization of the thorax. The branching pattern of the arteries of the thoracic aorta in O. bezoarticus was similar to domestic ruminants. In the M. gouazoubira and A. axis, there were no bicarotid trunk. Interestingly, the first branch of the brachiocephalic trunk was the left costocervical trunk in A. axis. Then, brachiocephalic trunk was divided into right and left subclavian arteries. M. gouazoubira and A. axis in contrast to O. bezoarticus were different when compared with other ruminants, and the absence of bicarotid trunk was more striking than previous reports. © 2014 Blackwell Verlag GmbH.

  8. Food irradiation: the facts

    International Nuclear Information System (INIS)

    Hamilton, M.

    1990-01-01

    The author explains in simple question and answer form what is entailed in the irradiation of food and attempts to dispel some of the anxieties surrounding the process. Benefits and limitations, controls, labelling safety, and tests for the detection of the use irradiation in food preparation are some of the topics dealt with in outline. (author)

  9. Food preservation by irradiation

    International Nuclear Information System (INIS)

    Labots, H.; Huis in 't Veld, G.J.P.; Verrips, C.T.

    1985-01-01

    After a review of several methods for the preservation of food and the routes of food infections, the following chapters are devoted to the preservation by irradiation. Applications and legal aspects of food irradiation are described. Special reference is made to the international situation. (Auth.)

  10. Perspective on food irradiation

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    Recent US Food and Drug Administration approval of irradiation treatment for fruit, vegetables and pork has stimulated considerable discussion in the popular press on the safety and efficacy of irradiation processing of food. This perspective is designed to summarize the current scientific information available on this issue

  11. Food irradiation: the facts

    International Nuclear Information System (INIS)

    Webb, Tony; Lang, Tim

    1987-01-01

    The London Food Commission summarizes its concerns about the use of food irradiation in the U.K. resulting from its working group surveys of general public opinion, trading standard officers and the food industry in the U.K., and from experience in countries already permitting irradiation to a variety of foods. (U.K.)

  12. Irradiation damage in superconductors

    International Nuclear Information System (INIS)

    Quere, Y.

    1989-01-01

    Most superconductors are quite sensitive to irradiation defects. Critical temperatures may be depressed, critical currents may be increased, by irradiation, but other behaviours may be encountered. In compounds, the sublattice in which defects are created is of significant importance. 24 refs

  13. Materials modified by irradiation

    International Nuclear Information System (INIS)

    Chmielewski, A.G.

    2007-01-01

    Application of radiation in pharmaceutical sciences and cosmetology, polymer materials, food industry, environment, health camre products and packing production is described. Nano-technology is described more detailed, because it is less known as irradiation using technology. Economic influence of the irradiation on the materials value addition is shown

  14. Food irradiation control

    International Nuclear Information System (INIS)

    Ley, F.J.

    1988-01-01

    A brief review is given of the control and monitoring of food irradiation with particular emphasis on the UK situation. After describing legal aspects, various applications of food irradiation in different countries are listed. Other topics discussed include code of practice for general control for both gamma radiation and electron beam facilities, dose specification, depth dose distribution and dosimetry. (U.K.)

  15. Irradiation Creep in Graphite

    Energy Technology Data Exchange (ETDEWEB)

    Ubic, Rick; Butt, Darryl; Windes, William

    2014-03-13

    An understanding of the underlying mechanisms of irradiation creep in graphite material is required to correctly interpret experimental data, explain micromechanical modeling results, and predict whole-core behavior. This project will focus on experimental microscopic data to demonstrate the mechanism of irradiation creep. High-resolution transmission electron microscopy should be able to image both the dislocations in graphite and the irradiation-induced interstitial clusters that pin those dislocations. The team will first prepare and characterize nanoscale samples of virgin nuclear graphite in a transmission electron microscope. Additional samples will be irradiated to varying degrees at the Advanced Test Reactor (ATR) facility and similarly characterized. Researchers will record microstructures and crystal defects and suggest a mechanism for irradiation creep based on the results. In addition, the purchase of a tensile holder for a transmission electron microscope will allow, for the first time, in situ observation of creep behavior on the microstructure and crystallographic defects.

  16. Issues in food irradiation

    International Nuclear Information System (INIS)

    Mills, S.

    1987-04-01

    This discussion paper has two goals: first, to raise public awareness of food irradiation, an emerging technology in which Canada has the potential to build a new industry, mainly oriented to promising overseas markets; and second, to help build consensus among government and private sector decision makers about what has to be done to realize the domestic and export potential. The following pages discuss the potential of food irradiation; indicate how food is irradiated; outline the uses of food irradiation; examine questions of the safety of the equipment and both the safety and nutritional value of irradiated food; look at international commercial developments; assess the current and emerging domestic scene; and finally, draw some conclusions and offer suggestions for action

  17. Extracorporeal irradiation -Physicist perspective

    International Nuclear Information System (INIS)

    Vijayaprabhu, N.; Saravanan, K.S.; Gunaseelan; Vivekanandam, S.; Reddy, K.S.; Parthasarathy; Mourougan, S.; Elangovan, K.

    2008-01-01

    Extracorporeal irradiation (ECI) involves irradiation of body tissues, particularly malignant bones of the extremities, outside the body. This involves en bloc resection of the tumour, extracorporeal irradiation of the bone segment with a single dose of 50 Gy or more, and reimplantation of the irradiated bone with fixation devices. Bone tumours like Ewing's Sarcoma, Chondrosarcoma and Oesteosarcoma; in the involved sites like femur, tibia, humerus, ilium and sacrum can be treated with ECI. The reimplanted bone simply acts as a framework for appositional bone growth from surrounding healthy bones. The conventional indications for postoperative irradiation are still applied. The major advantages of ECI are the precise anatomic fit of the reimplanted bone segment, preservation of joint mobility and its potential in avoiding the growth discrepancy commonly seen in prosthetic replacement. The use of ECI was first described in 1968 and practiced in Australia since 1996. In our center, we have completed six ECIs

  18. Upgrade to the Birmingham Irradiation Facility

    Science.gov (United States)

    Dervan, P.; French, R.; Hodgson, P.; Marin-Reyes, H.; Parker, K.; Wilson, J.; Baca, M.

    2015-10-01

    The Birmingham Irradiation Facility was developed in 2013 at the University of Birmingham using the Medical Physics MC40 cyclotron. It can achieve High Luminosity LHC (HL-LHC) fluences of 1015 (1 MeV neutron equivalent (neq)) cm-2 in 80 s with proton beam currents of 1 μA and so can evaluate effectively the performance and durability of detector technologies and new components to be used for the HL-LHC. Irradiations of silicon sensors and passive materials can be carried out in a temperature controlled cold box which moves continuously through the homogenous beamspot. This movement is provided by a pre-configured XY-axis Cartesian robot scanning system. In 2014 the cooling system and cold box were upgraded from a recirculating glycol chiller system to a liquid nitrogen evaporative system. The new cooling system achieves a stable temperature of -50 °C in 30 min and aims to maintain sub-0 °C temperatures on the sensors during irradiations. This paper reviews the design, development, commissioning and performance of the new cooling system.

  19. Upgrade to the Birmingham Irradiation Facility

    CERN Document Server

    Dervan, P; Hodgson, P; Marin- Reyes; Parker, K; Wilson, J; Baca, M

    2015-01-01

    The Birmingham Irradiation Facility was developed in 2013 at the University of Birmingham using the Medical Physics MC40 cyclotron. It can achieve High Luminosity LHC (HL-LHC) fluences of 10^15 (1 MeV neutron equivalent (neq)) cm^-2 in 80 s with proton beam currents of 1 μA and so can evaluate effectively the performance and durability of detector technologies and new components to be used for the HL-LHC. Irradiations of silicon sensors and passive materials can be carried out in a temperature controlled cold box which moves continuously through the homogenous beamspot. This movement is provided by a pre-configured XY-axis Cartesian robot scanning system. In 2014 the cooling system and cold box were upgraded from a recirculating glycol chiller system to a liquid nitrogen evaporative system. The new cooling system achieves a stable temperature of 50 1C in 30 min and aims to maintain sub-0 1C temperatures on the sensors during irradiations. This paper reviews the design, development, commissioning and perform...

  20. FTIR spectroscopy of electron irradiated polymers

    International Nuclear Information System (INIS)

    Finch, D.S.

    1988-04-01

    The chemical changes in electron beam irradiated polymers, in particular PVC, are considered in order to relate the formation of conjugated structures to changes in the electrical properties. Infrared spectroscopy has been used to measure these changes. Fourier Transform techniques and computing facilities make better data processing possible. A method for base line interpretation is demonstrated whereby a shift parallel to the abscisal axis in a region of the polymer that is non absorbing is used to evaluate the baseline. This technique has proved to be highly reproducible providing that the polymer films to be examined are optically homogeneous. Evaluation of the rate of decay of the total area of the carbon chlorine region of the polymer has been compared with the chlorine decay curve analysed by the measurement of x-ray emission during irradiation of bulk samples. The significant reduction in the evolution of atomic chlorine through x-ray analysis has been attributed to the trapping of HCl within the polymer film and its subsequent slow diffusion out of the polymer. With PVC, one of the main products as a result of irradiation is the formation of conjugated sequences. These were studied by the use of uv-visible spectroscopy. (author)

  1. Comparison of Pyranometers and Reference Cells on Fixed and One-Axis Tracking Surfaces: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Dooraghi, Michael R [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Sengupta, Manajit [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Vignola, Frank [University of Oregon; Peterson, Josh [University of Oregon; Mavromatakis, Fotis [Technological Educational Institute of Crete; Chiu, Chun-Yu [University of Oregon

    2017-12-19

    A wide variety of sensors are used to monitor the irradiance incident on solar modules to evaluate the performance of photovoltaic (PV) systems. These instruments range from secondary standard pyranometers to photodiode-based pyranometers to reference cells. Although instruments are mounted in the plane of array of the modules, a wide range of results have been obtained. Some of these difference have been assumed to come from systematic uncertainties associated with the irradiance sensors. This study is an attempt to quantify these differences by comparing the output of selected thermopile pyranometers to photodiode-based pyranometers and reference cells on a horizontal surface, a fixed-tilt surface, and a one-axis tracking surface. This analysis focuses on clear-sky results from two sites with different climatic conditions. Several important features were observed. Photodiode-based pyranometers and reference cells produce widely different results under clear skies, especially at larger angles of incidence, even though both instruments are based on measuring the short-circuit current of solar cells. The difference is caused by the scattering of light as it passes through the glazing of the reference cell or the diffuser lens of the photodioded-base pyranometer. Both instruments are shown to have similar response to the spectral distribution of the irradiance when compared to the thermopile-based pyranometer, which has a response nearly independent of the wavelength of light used by PV modules.

  2. A Method for Modeling of Floating Vertical Axis Wind Turbine

    DEFF Research Database (Denmark)

    Wang, Kai; Hansen, Martin Otto Laver; Moan, Torgeir

    2013-01-01

    It is of interest to investigate the potential advantages of floating vertical axis wind turbine (FVAWT) due to its economical installation and maintenance. A novel 5MW vertical axis wind turbine concept with a Darrieus rotor mounted on a semi-submersible support structure is proposed in this paper....... In order to assess the technical and economic feasibility of this novel concept, a comprehensive simulation tool for modeling of the floating vertical axis wind turbine is needed. This work presents the development of a coupled method for modeling of the dynamics of a floating vertical axis wind turbine...

  3. Concept of a Programmable Fixture for 3-Axis CNC

    Directory of Open Access Journals (Sweden)

    Ahmad Dalloul

    2017-09-01

    Full Text Available CNC machine is the one of the major reasons for industrial advancement in recent decades for its ability of producing accurate parts. The most commen CNC machines are of 3-axis and adopted widely in the industrial sector. However, for producing more complicated parts 5-axis CNC machines are required. Although the introduction of the 5-axis machine came after the 3-axis CNC machine has established itself and many manufacturers did not make the move toward the newer model and its high pricing compared to the 3-axis model did not help either. In this time the development of a fixture or a platform to help transfer the 3-axis to a 5-axis to some degree. This paper discusses the concept of a programmable fixture that gives 3-axis CNC machine the freedom to act in similar manner as the 5-axis. The paper describes the mechanism with some initial results of the testing. Result showed that the platform moves in translation manner with an average error of 5.58 % and 7.303% average error for rotation movement.

  4. Suicidal behavior on Axis VI: clinical data supporting a sixth Axis for DSM-V.

    Science.gov (United States)

    Van Orden, Kimberly A; Witte, Tracy K; Holm-Denoma, Jill; Gordon, Kathryn H; Joiner, Thomas E

    2011-01-01

    Oquendo and colleagues (Oquendo, Baca-García, Mann, & Giner, 2008; Oquendo & Currier, 2009) recommend that DSM-V emphasize suicide risk assessment on a sixth axis, thereby increasing regularity of suicide risk assessments. We propose that evidence of nonredundancy with Axis V - Global Assessment of Functioning (GAF) is one piece of data that can serve as a starting point for a line of research establishing incremental predictive utility for a separate suicide risk assessment in the DSM framework. A standardized suicide risk assessment protocol, measures of depressive, anxious, and eating disordered symptomatology, as well as an index of comorbidity were administered to a sample of 412 adult outpatients. Our data indicate that data from standardized suicide risk assessments are associated with indices of symptomatology severity as well as comorbidity, controlling for GAF. These results support the nonredundancy of the assessments and suggest the utility of longitudinal investigations of the predictive utility of a sixth DSM axis in the assessment of suicide risk.

  5. Food irradiation 2009

    International Nuclear Information System (INIS)

    Narvaiz, Patricia

    2009-01-01

    Food irradiation principles; its main applications, advantages and limitations; wholesomeness, present activities at Ezeiza Atomic Centre; research coordinated by the International Atomic Energy Agency; capacity building; and some aspects on national and international regulations, standards and commercialization are briefly described. At present 56 countries authorize the consumption of varied irradiated foods; trade is performed in 32 countries, with about 200 irradiation facilities. Argentina pioneered nuclear energy knowledge and applications in Latin America, food irradiation included. A steady growth of food industrial volumes treated in two gamma facilities can be observed. Food industry and producers show interest towards new facilities construction. However, a 15 years standstill in incorporating new approvals in the Argentine Alimentary Code, in spite of consecutive request performed either by CNEA or some food industries restricts, a wider industrial implementation, which constitute a drawback to future regional commercialization in areas such as MERCOSUR, where Brazil since 2000 freely authorize food irradiation. Besides, important chances in international trade with developed countries will be missed, like the high fresh fruits and vegetables requirements United States has in counter-season, leading to convenient sale prices. The Argentine food irradiation facilities have been designed and built in the country. Argentina produces Cobalt-60. These capacities, unusual in the world and particularly in Latin America, should be protected and enhanced. Being the irradiation facilities scarce and concentrated nearby Buenos Aires city, the possibilities of commercial application and even research and development are strongly limited for most of the country regions. (author) [es

  6. Burnable poison irradiation test

    International Nuclear Information System (INIS)

    1977-08-01

    The topical report describes the irradiation program developed to investigate different burnable poison rod material and designs. The purpose of the report is to present (1) technical support for the irradiation of several test burnable poison rod designs that have not been previously reviewed, and (2) describe the parameters that will be employed in the surveillance program for Combustion Engineering's (CE) standard burnable poison rod for 16 x 16 fuel assemblies. The test burnable poison rods will be placed in a CE reactor using 16 x 16 fuel assemblies, the first such reactor is Arkansas Nuclear One, Unit 2. The irradiation program has four phases. Phase I involves the irradiation of 48 standard burnable poison rods which (1) will be extensively precharacterized prior to irradiation and (2) will undergo interim performance evaluation and detailed post-irradiation examination. Phase II, III, and IV involve irradiation and performance evaluation of a small number of burnable poison rods of different proprietary designs. The report discusses the materials to be used in each phase, the methods of fabricating the rods, and the rods expected behavior in a reactor

  7. Irradiation-Induced Nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Birtcher, R.C.; Ewing, R.C.; Matzke, Hj.; Meldrum, A.; Newcomer, P.P.; Wang, L.M.; Wang, S.X.; Weber, W.J.

    1999-08-09

    This paper summarizes the results of the studies of the irradiation-induced formation of nanostructures, where the injected interstitials from the source of irradiation are not major components of the nanophase. This phenomena has been observed by in situ transmission electron microscopy (TEM) in a number of intermetallic compounds and ceramics during high-energy electron or ion irradiations when the ions completely penetrate through the specimen. Beginning with single crystals, electron or ion irradiation in a certain temperature range may result in nanostructures composed of amorphous domains and nanocrystals with either the original composition and crystal structure or new nanophases formed by decomposition of the target material. The phenomenon has also been observed in natural materials which have suffered irradiation from the decay of constituent radioactive elements and in nuclear reactor fuels which have been irradiated by fission neutrons and other fission products. The mechanisms involved in the process of this nanophase formation are discussed in terms of the evolution of displacement cascades, radiation-induced defect accumulation, radiation-induced segregation and phase decomposition, as well as the competition between irradiation-induced amorphization and recrystallization.

  8. Irradiation test of Dupic fuel

    International Nuclear Information System (INIS)

    Kee, Chan Song; Myung, Seung Yang; Hyun, Soo Park

    2002-01-01

    Simulated DUPIC fuel that had been fabricated from natural uranium oxide with simulated fission products was irradiated at the HANARO research reactor at KAERI in 1999. The objectives of this irradiation test were to estimate the in-core behaviour of DUPIC fuel, to verify the design of the non-instrumented irradiation rig developed for the irradiation test of DUPIC fuel and to ensure the irradiation requirements of DUPIC fuel at HANARO. The post-irradiation examinations, such as dimensional measurement, γ-scanning and EPMA, for irradiated simulated DUPIC fuel have been performed at the IMEF. The irradiation test of DUPIC fuel, fabricated with spent PWR fuel material, was performed at HANARO for two months as of May 2000. The resultant burn-up of irradiated DUPIC fuel was estimated to be 1 800 MWd/MTU. The irradiation behaviour of DUPIC fuel will be investigated based on the data from post-irradiation examinations. (authors)

  9. Yaw dynamics of horizontal axis wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, A.C. (Utah Univ., Salt Lake City, UT (United States))

    1992-05-01

    Designers of a horizontal axis wind turbine yaw mechanism are faced with a difficult decision. They know that if they elect to use a yaw- controlled rotor then the system will suffer increased initial cost and increased inherent maintenance and reliability problems. On the other hand, if they elect to allow the rotor to freely yaw they known they will have to account for unknown and random, though bounded, yaw rates. They will have a higher-risk design to trade-off against the potential for cost savings and reliability improvement. The risk of a yaw-free system could be minimized if methods were available for analyzing and understanding yaw behavior. The complexity of yaw behavior has, until recently, discouraged engineers from developing a complete yaw analysis method. The objectives of this work are to (1) provide a fundamental understanding of free-yaw mechanics and the design concepts most effective at eliminating yaw problems, and (2) provide tested design tools and guidelines for use by free-yaw wind systems manufacturers. The emphasis is on developing practical and sufficiently accurate design methods.

  10. Microbiota and the gut-brain axis.

    Science.gov (United States)

    Bienenstock, John; Kunze, Wolfgang; Forsythe, Paul

    2015-08-01

    Changes in gut microbiota can modulate the peripheral and central nervous systems, resulting in altered brain functioning, and suggesting the existence of a microbiota gut-brain axis. Diet can also change the profile of gut microbiota and, thereby, behavior. Effects of bacteria on the nervous system cannot be disassociated from effects on the immune system since the two are in constant bidirectional communication. While the composition of the gut microbiota varies greatly among individuals, alterations to the balance and content of common gut microbes may affect the production of molecules such as neurotransmitters, e.g., gamma amino butyric acid, and the products of fermentation, e.g., the short chain fatty acids butyrate, propionate, and acetate. Short chain fatty acids, which are pleomorphic, especially butyrate, positively influence host metabolism by promoting glucose and energy homeostasis, regulating immune responses and epithelial cell growth, and promoting the functioning of the central and peripheral nervous systems. In the future, the composition, diversity, and function of specific probiotics, coupled with similar, more detailed knowledge about gut microbiota, will potentially help in developing more effective diet- and drug-based therapies. © The Author(s) 2015. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  11. Gut/brain axis and the microbiota.

    Science.gov (United States)

    Mayer, Emeran A; Tillisch, Kirsten; Gupta, Arpana

    2015-03-02

    Tremendous progress has been made in characterizing the bidirectional interactions between the central nervous system, the enteric nervous system, and the gastrointestinal tract. A series of provocative preclinical studies have suggested a prominent role for the gut microbiota in these gut-brain interactions. Based on studies using rodents raised in a germ-free environment, the gut microbiota appears to influence the development of emotional behavior, stress- and pain-modulation systems, and brain neurotransmitter systems. Additionally, microbiota perturbations by probiotics and antibiotics exert modulatory effects on some of these measures in adult animals. Current evidence suggests that multiple mechanisms, including endocrine and neurocrine pathways, may be involved in gut microbiota-to-brain signaling and that the brain can in turn alter microbial composition and behavior via the autonomic nervous system. Limited information is available on how these findings may translate to healthy humans or to disease states involving the brain or the gut/brain axis. Future research needs to focus on confirming that the rodent findings are translatable to human physiology and to diseases such as irritable bowel syndrome, autism, anxiety, depression, and Parkinson's disease.

  12. Creating a Multi-axis Machining Postprocessor

    Directory of Open Access Journals (Sweden)

    Petr Vavruška

    2012-01-01

    Full Text Available This paper focuses on the postprocessor creation process. When using standard commercially available postprocessors it is often very difficult to modify its internal source code, and it is a very complex process, in many cases even impossible, to implement the newly-developed functions. It is therefore very important to have a method for creating a postprocessor for any CAM system, which allows CL data (Cutter Location data to be generated to a separate text file. The goal of our work is to verify the proposed method for creating a postprocessor. Postprocessor functions for multi-axis machiningare dealt with in this work. A file with CL data must be translated by the postprocessor into an NC program that has been customized for a specific production machine and its control system. The postprocessor is therefore verified by applications for machining free-form surfaces of complex parts, and by executing the NC programs that are generated on real machine tools. This is also presented here.

  13. Alaskan Commodities Irradiation Project

    International Nuclear Information System (INIS)

    Zarling, J.P.; Swanson, R.B.; Logan, R.R.

    1988-01-01

    The ninety-ninth US Congress commissioned a six-state food irradiation research and development program to evaluate the commercial potential of this technology. Hawaii, Washington, Iowa, Oklahoma and Florida as well as Alaska have participated in the national program; various food products including fishery products, red meats, tropical and citrus fruits and vegetables have been studied. The purpose of the Alaskan study was to review and evaluate those factors related to the technical and economic feasibility of an irradiator in Alaska. This options analysis study will serve as a basis for determining the state's further involvement in the development of food irradiation technology. 40 refs., 50 figs., 53 tabs

  14. Analysis of irradiated food

    International Nuclear Information System (INIS)

    Meier, W.

    1991-01-01

    Foods, e.g. chicken, shrimps, frog legs, spices, different dried vegetables, potatoes and fruits are legally irradiated in many countries and are probably also exported into countries, which do not permit irradiation of any food. Therefore all countries need analytical methods to determine whether food has been irradiated or not. Up to now, two physical (ESR-spectroscopy and thermoluminescence) and two chemical methods (o-tyrosine and volatile compounds) are available for routine analysis. Several results of the application of these four mentioned methods on different foods are presented and a short outlook on other methods (chemiluminescence, DNA-changes, biological assays, viscometric method and photostimulated luminescence) will be given. (author)

  15. Facts about food irradiation: Irradiated foods and the consumer

    International Nuclear Information System (INIS)

    1991-01-01

    This fact sheet discusses market testing of irradiate food, consumer response to irradiated products has always been positive, and in some countries commercial quantities of some irradiated food items have been sold on a regular basis. Consumers have shown no reluctance to buy irradiated food products. 4 refs

  16. Food irradiation now

    International Nuclear Information System (INIS)

    1982-01-01

    From the start the Netherlands has made an important contribution to the irradiation of food through microbiological and toxicological research as well as through the setting-up of a pilot plant by the government and through the practical application of 'Gammaster' on a commercial basis. The proceedings of this tenth anniversary symposium of 'Gammaster' present all aspects of food irradiation and will undoubtedly help to remove the many misunderstandings. They offer information and indicate to the potential user a method that can make an important contribution to the prevention of decay and spoilage of foodstuffs and to the exclusion of food-borne infections and food poisoning in man. The book includes 8 contributions and 4 panel discussions in the field of microbiology; technology; legal aspects; and consumer aspects of food irradiation. As an appendix, the report 'Wholesomeness of irradiated food' of a joint FAO/IAEA/WHO Expert Committee has been added. (orig./G.J.P.)

  17. Food preservation by irradiation

    International Nuclear Information System (INIS)

    Oztasiran, I.

    1984-01-01

    Irradiation is a physical process for treating food and as such it is comparable to other processing techniques such as heating or freezing foods for preservation. The energy level used in food irradiation is always below that producing radioactivity in the treated food, hence this aspect can be totally excluded in wholesomeness evaluations. Water is readily ionized and may be the primary source of ionization in foods with secondary effects on other molecules, possibly more a result of water ionization than of direct hits. In the presence of oxygen, highly reactive compounds may be produced, such as H, H 3 0+ and H 2 O 2 . Radiation at the energy flux levels used for food (<2 MeV) does not induce radioactivity. Food irradiation applications are already technically and economically feasible and that food so treated is suitable for consumption. Food irradiation techniques can play an important role for an improved preservation, storage and distribution of food products. (author)

  18. Packing for food irradiation

    International Nuclear Information System (INIS)

    Chmielewski, A.G.

    2006-01-01

    Joint FAO/IAEA/WHO Expert Committee approved the use of radiation treatment of foods. Nowadays food packaging are mostly made of plastics, natural or synthetic, therefore effect of irradiation on these materials is crucial for packing engineering for food irradiation technology. By selecting the right polymer materials for food packaging it can be ensured that the critical elements of material and product performance are not compromised. When packaging materials are in contact with food at the time of irradiation that regulatory approvals sometimes apply. The review of the R-and-D and technical papers regarding material selection, testing and approval is presented in the report. The most information come from the USA where this subject is well elaborated, the International Atomic Energy Agency (IAEA) reports are reviewed as well. The report can be useful for scientists and food irradiation plants operators. (author)

  19. Sterilization by gamma irradiation

    International Nuclear Information System (INIS)

    Reyes Frias, L.

    1992-01-01

    Since 1980 the National Institute of Nuclear Research counts with an Industrial Gamma Irradiator, for the sterilization of raw materials and finished products. Through several means has been promoted the use of this technology as alternative to conventional methods of sterilization as well as steam treatment and ethylene oxide. As a result of the made promotion this irradiator has come to its saturation limit being the sterilization irradiation one of the main services that National Institute of Nuclear Research offers to producer enterprises of disposable materials of medical use also of raw materials for the elaboration of cosmetic products and pharmaceuticals as well as dehydrated foods. It is presented the trend to the sterilization service by irradiation showed by the compilation data in a survey made by potential customers. (Author)

  20. Economics of food irradiation

    International Nuclear Information System (INIS)

    Deitch, J.

    1982-01-01

    This article examines the cost competitiveness of the food irradiation process. An analysis of the principal factors--the product, physical plant, irradiation source, and financing--that impact on cost is made. Equations are developed and used to calculate the size of the source for planned product throughput, efficiency factors, power requirements, and operating costs of sources, radionuclides, and accelerators. Methods of financing and capital investment are discussed. A series of tables show cost breakdowns of sources, buildings, equipment, and essential support facilities for both a cobalt-60 and a 10-MeV electron accelerator facility. Additional tables present irradiation costs as functions of a number of parameters--power input, source size, dose, and hours of annual operation. The use of the numbers in the tables are explained by examples of calculations of the irradiation costs for disinfestation of grains and radicidation of feed

  1. Food irradiation in perspective

    International Nuclear Information System (INIS)

    Henon, Y.M.

    1995-01-01

    Food irradiation already has a long history of hopes and disappointments. Nowhere in the world it plays the role that it should have, including in the much needed prevention of foodborne diseases. Irradiated food sold well wherever consumers were given a chance to buy them. Differences between national regulations do not allow the international trade of irradiated foods. While in many countries food irradiation is still illegal, in most others it is regulated as a food additive and based on the knowledge of the sixties. Until 1980, wholesomeness was the big issue. Then the ''prerequisite'' became detection methods. Large amounts of money have been spent to design and validate tests which, in fact, aim at enforcing unjustified restrictions on the use of the process. In spite of all the difficulties, it is believed that the efforts of various UN organizations and a growing legitimate demand for food safety should in the end lead to recognition and acceptance. (Author)

  2. Dosimetry for food irradiation

    International Nuclear Information System (INIS)

    2002-01-01

    A Manual of Food Irradiation Dosimetry was published in 1977 under the auspices of the IAEA as Technical Reports Series No. 178. It was the first monograph of its kind and served as a reference in the field of radiation processing and in the development of standards. While the essential information about radiation dosimetry in this publication has not become obsolete, other publications on radiation dosimetry have become available which have provided useful information for incorporation in this updated version. There is already a Codex General Standard for Irradiated Foods and an associated Code of Practice for Operation of Irradiation Facilities used for Treatment of Food, issued in 1984 by the Codex Alimentarius Commission of the FAO/WHO Food Standard Programme. The Codex Standard contains provisions on irradiation facilities and process control which include, among other requirements, that control of the processes within facilities shall include the keeping of adequate records including quantitative dosimetry. Appendix A of the Standard provides an explanation of process control and dosimetric requirements in compliance with the Codex Standard. By 1999, over 40 countries had implemented national regulations or issued specific approval for certain irradiated food items/classes of food based on the principles of the Codex Standard and its Code of Practice. Food irradiation is thus expanding, as over 30 countries are now actually applying this process for the treatment of one or more food products for commercial purposes. Irradiated foods are being marketed at retail level in several countries. With the increasing recognition and application of irradiation as a sanitary and phytosanitary treatment of food based on the provisions of the Agreement on the Application of Sanitary and Phytosanitary Measures of the World Trade Organization, international trade in irradiated food is expected to expand during the next decade. It is therefore essential that proper dosimetry

  3. Axis: Generating Explanations at Scale with Learnersourcing and Machine Learning

    Science.gov (United States)

    Williams, Joseph Jay; Kim, Juho; Rafferty, Anna; Heffernan, Neil; Maldonado, Samuel; Gajos, Krzysztof Z.; Lasecki, Walter S.; Heffernan, Neil

    2016-01-01

    While explanations may help people learn by providing information about why an answer is correct, many problems on online platforms lack high-quality explanations. This paper presents AXIS (Adaptive eXplanation Improvement System), a system for obtaining explanations. AXIS asks learners to generate, revise, and evaluate explanations as they solve…

  4. A psychology of the human brain-gut-microbiome axis.

    Science.gov (United States)

    Allen, Andrew P; Dinan, Timothy G; Clarke, Gerard; Cryan, John F

    2017-04-01

    In recent years, we have seen increasing research within neuroscience and biopsychology on the interactions between the brain, the gastrointestinal tract, the bacteria within the gastrointestinal tract, and the bidirectional relationship between these systems: the brain-gut-microbiome axis. Although research has demonstrated that the gut microbiota can impact upon cognition and a variety of stress-related behaviours, including those relevant to anxiety and depression, we still do not know how this occurs. A deeper understanding of how psychological development as well as social and cultural factors impact upon the brain-gut-microbiome axis will contextualise the role of the axis in humans and inform psychological interventions that improve health within the brain-gut-microbiome axis. Interventions ostensibly aimed at ameliorating disorders in one part of the brain-gut-microbiome axis (e.g., psychotherapy for depression) may nonetheless impact upon other parts of the axis (e.g., microbiome composition and function), and functional gastrointestinal disorders such as irritable bowel syndrome represent a disorder of the axis, rather than an isolated problem either of psychology or of gastrointestinal function. The discipline of psychology needs to be cognisant of these interactions and can help to inform the future research agenda in this emerging field of research. In this review, we outline the role psychology has to play in understanding the brain-gut-microbiome axis, with a focus on human psychology and the use of research in laboratory animals to model human psychology.

  5. Angular momentum projection of tilted axis rotating states

    Energy Technology Data Exchange (ETDEWEB)

    Oi, M.; Onishi, N.; Tajima, N. [Tokyo Univ. (Japan); Horibata, T.

    1998-03-01

    We applied an exact angular momentum projection to three dimensional cranked HFB (3d-CHFB) states. Tilted axis rotating states (TAR) and principal axis rotating states (PAR) are compared. It is shown that TAR is more adequate than PAR for description of the back bending phenomena driven by tilted rotation or wobbling motion. (author)

  6. Dead-end tract of the conduction axis

    NARCIS (Netherlands)

    Kurosawa, H.; Becker, A. E.

    1985-01-01

    In the definitive heart the anterior continuation of the main conduction axis is considered to be the right bundle branch. In this study three hearts from neonates and infants were examined in which this situation did not pertain. The conduction axis continued beyond the point of origin of the right

  7. The Performance Characteristics of a Closed Loop, One Axis ...

    African Journals Online (AJOL)

    This paper presents a closed loop one axis solar tracking device of the polar axis type, which achieves an accurate tracking of the sun with a steady state error of less, than 2%. This prototype uses a photo-sensing system to generate an error signal. This error signal switches on a relay, which actuates an electromechanical ...

  8. Spin-stabilized magnetic levitation without vertical axis of rotation

    Science.gov (United States)

    Romero, Louis [Albuquerque, NM; Christenson, Todd [Albuquerque, NM; Aaronson, Gene [Albuquerque, NM

    2009-06-09

    The symmetry properties of a magnetic levitation arrangement are exploited to produce spin-stabilized magnetic levitation without aligning the rotational axis of the rotor with the direction of the force of gravity. The rotation of the rotor stabilizes perturbations directed parallel to the rotational axis.

  9. Investigation of blade performance of horizontal axis wind turbine ...

    African Journals Online (AJOL)

    The shape of rotor blade plays an important role in determining the overall aerodynamic performance of a horizontal axis wind turbine. In this work, blade is designed for a 5KW horizontal axis wind turbine which is already in market. For designing blade, blade element momentum theory (BEMT) is used and a computer ...

  10. A psychology of the human brain–gut–microbiome axis

    Science.gov (United States)

    Allen, Andrew P.; Dinan, Timothy G.; Clarke, Gerard

    2017-01-01

    Abstract In recent years, we have seen increasing research within neuroscience and biopsychology on the interactions between the brain, the gastrointestinal tract, the bacteria within the gastrointestinal tract, and the bidirectional relationship between these systems: the brain–gut–microbiome axis. Although research has demonstrated that the gut microbiota can impact upon cognition and a variety of stress‐related behaviours, including those relevant to anxiety and depression, we still do not know how this occurs. A deeper understanding of how psychological development as well as social and cultural factors impact upon the brain–gut–microbiome axis will contextualise the role of the axis in humans and inform psychological interventions that improve health within the brain–gut–microbiome axis. Interventions ostensibly aimed at ameliorating disorders in one part of the brain–gut–microbiome axis (e.g., psychotherapy for depression) may nonetheless impact upon other parts of the axis (e.g., microbiome composition and function), and functional gastrointestinal disorders such as irritable bowel syndrome represent a disorder of the axis, rather than an isolated problem either of psychology or of gastrointestinal function. The discipline of psychology needs to be cognisant of these interactions and can help to inform the future research agenda in this emerging field of research. In this review, we outline the role psychology has to play in understanding the brain–gut–microbiome axis, with a focus on human psychology and the use of research in laboratory animals to model human psychology. PMID:28804508

  11. Sequence-dependent rotation axis changes in tennis.

    Science.gov (United States)

    Hansen, Clint; Martin, Caroline; Rezzoug, Nasser; Gorce, Philippe; Bideau, Benoit; Isableu, Brice

    2017-09-01

    The purpose of this study was to evaluate the role of rotation axes during a tennis serve. A motion capture system was used to evaluate the contribution of the potential axes of rotation (minimum inertia axis, shoulder-centre of mass axis and the shoulder-elbow axis) during the four discrete tennis serve phases (loading, cocking, acceleration and follow through). Ten ranked athletes (International Tennis Number 1-3) repeatedly performed a flat service aiming at a target on the other side of the net. The four serve phases are distinct and thus, each movement phase seems to be organised around specific rotation axes. The results showed that the limbs' rotational axis does not necessarily coincide with the minimum inertia axis across the cocking phase of the tennis serve. Even though individual serving strategies were exposed, all participants showed an effect due to the cocking phase and changed the rotation axis during the task. Taken together, the results showed that despite inter-individual differences, nine out of 10 participants changed the rotation axis towards the minimum inertia and/or the mass axis in an endeavour to maximise external rotation of the shoulder to optimally prepare for the acceleration phase.

  12. Food irradiation: progress in Canada

    International Nuclear Information System (INIS)

    Wilson, B.K.

    1985-01-01

    The subject is discussed under the headings: food irradiation regulatory situation in Canada; non-regulatory developments (poultry irradiation; fish irradiation; Government willingness to fund industry initiated projects; Government willingness to establish food irradiation research and pilot plant facilities; food industry interest is increasing significantly; Canadian Consumers Association positive response; the emergence of new consulting and entrepreneurial firms). (U.K.)

  13. Food irradiation in Malaysia

    International Nuclear Information System (INIS)

    Mohd Ghazali Hj Abd Rahman.

    1985-01-01

    Food irradiation has recently been visited as a technology that can contribute to the solution of problems associated with food preservation of Malaysia's agriculture produce and products thereby improving the economic status of the rural sector. However, the history of food irradiation in Malaysia is very recent. Research carried out on food irradiation only began in 1974 as a result of the installation of a 60 Co facility (initially 10,000 Ci) at the National University of Malaysia. Since its installation several studies have been carried out pertaining to the food irradiation. Presently its development has been slow. Research in this area has been confined to laboratory scale and purely academic. This limitation is due to a number of reasons, among others are: a) limited number of facilities; b) lack of expertise to conduct its research; c) other preservation methods can be improved with lower capital output. An important step towards its development was made when Malaysia actively participated in the RCA/IAEA food irradiation project, viz. the irradiation of pepper which was carried out at the National University of Malaysia in the 80's. As a result of this venture, research and development activities in food irradiation have been geared toward semi-plot scale with the view ot commercialization in the future. In 1982, a group of researchers was formed to conduct feasibility studies using irradiation techniques in trying to overcome several problems associated with our local paddy and rice. Another group is being organized by the National University of Malaysia to look into the problems associated with the preservation of frozen shrimps. (author)

  14. Irradiation of chilled lamb

    International Nuclear Information System (INIS)

    Roberts, P.B.

    1985-04-01

    Chilled, vacuum-packed New Zealand lamb loins have been irradiated at doses between 1-8 kGy. The report outlines the methods used and provides dosimetry details. An appendix summarises the results of a taste trial conducted on the irradiated meat by the Meat Industry Research Institute of New Zealand. This showed that, even at 1 kGy, detectable flavours were induced by the radiation treatment

  15. AGC-2 Irradiation Report

    Energy Technology Data Exchange (ETDEWEB)

    Rohrbaugh, David Thomas [Idaho National Lab. (INL), Idaho Falls, ID (United States); Windes, William [Idaho National Lab. (INL), Idaho Falls, ID (United States); Swank, W. David [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-06-01

    The Next Generation Nuclear Plant (NGNP) will be a helium-cooled, very high temperature reactor (VHTR) with a large graphite core. In past applications, graphite has been used effectively as a structural and moderator material in both research and commercial high temperature gas cooled reactor (HTGR) designs.[ , ] Nuclear graphite H 451, used previously in the United States for nuclear reactor graphite components, is no longer available. New nuclear graphites have been developed and are considered suitable candidates for the new NGNP reactor design. To support the design and licensing of NGNP core components within a commercial reactor, a complete properties database must be developed for these current grades of graphite. Quantitative data on in service material performance are required for the physical, mechanical, and thermal properties of each graphite grade with a specific emphasis on data related to the life limiting effects of irradiation creep on key physical properties of the NGNP candidate graphites. Based on experience with previous graphite core components, the phenomenon of irradiation induced creep within the graphite has been shown to be critical to the total useful lifetime of graphite components. Irradiation induced creep occurs under the simultaneous application of high temperatures, neutron irradiation, and applied stresses within the graphite components. Significant internal stresses within the graphite components can result from a second phenomenon—irradiation induced dimensional change. In this case, the graphite physically changes i.e., first shrinking and then expanding with increasing neutron dose. This disparity in material volume change can induce significant internal stresses within graphite components. Irradiation induced creep relaxes these large internal stresses, thus reducing the risk of crack formation and component failure. Obviously, higher irradiation creep levels tend to relieve more internal stress, thus allowing the

  16. Food irradiation: global aspects

    International Nuclear Information System (INIS)

    Vinning, G.

    1988-01-01

    As a commercial activity, food irradiation is twenty years old, but is backed by nearly eighty years of research on gamma irradiation and sixty years knowledge of application of the technology to food. An overview is given of the global boom and then the hiatus in its legislative and commercial applications. It is emphasised that in Australia, the overseas experience provides a number of models for proceeding further for food manufacturers, consumers and Government. 13 refs

  17. IAEA and food irradiation

    International Nuclear Information System (INIS)

    Machi, Sueo

    1995-01-01

    IAEA was founded in 1957. 122 countries take part in it. It is operated with the yearly ordinary budget of about 20 billion yen and the technical cooperation budget of about 6 billion yen and by 2200 personnel. Its two important roles are the promotion of the peaceful utilization of atomic energy and the prevention of nuclear proliferation. The activities of IAEA are shown. The cooperation with developing countries and the international research cooperation program are the important activities. The securing of foods is an urgent subject, and the utilization of radiation and isotopes has been promoted, aiming at sustaining agriculture. The necessity of food irradiation is explained, and at present, commercial food irradiation is carried out in 28 countries including Japan. The irradiation less than 10 kGy does not cause poisonous effect in any food, according to JECFI. The new international agreement is expected to be useful for promoting the international trade of irradiated foods. The international cooperation for the spread of food irradiation and the public acceptance of food irradiation are reported. (K.I.)

  18. Total lymphoid irradiation

    International Nuclear Information System (INIS)

    Sutherland, D.E.; Ferguson, R.M.; Simmons, R.L.; Kim, T.H.; Slavin, S.; Najarian, J.S.

    1983-01-01

    Total lymphoid irradiation by itself can produce sufficient immunosuppression to prolong the survival of a variety of organ allografts in experimental animals. The degree of prolongation is dose-dependent and is limited by the toxicity that occurs with higher doses. Total lymphoid irradiation is more effective before transplantation than after, but when used after transplantation can be combined with pharmacologic immunosuppression to achieve a positive effect. In some animal models, total lymphoid irradiation induces an environment in which fully allogeneic bone marrow will engraft and induce permanent chimerism in the recipients who are then tolerant to organ allografts from the donor strain. If total lymphoid irradiation is ever to have clinical applicability on a large scale, it would seem that it would have to be under circumstances in which tolerance can be induced. However, in some animal models graft-versus-host disease occurs following bone marrow transplantation, and methods to obviate its occurrence probably will be needed if this approach is to be applied clinically. In recent years, patient and graft survival rates in renal allograft recipients treated with conventional immunosuppression have improved considerably, and thus the impetus to utilize total lymphoid irradiation for its immunosuppressive effect alone is less compelling. The future of total lymphoid irradiation probably lies in devising protocols in which maintenance immunosuppression can be eliminated, or nearly eliminated, altogether. Such protocols are effective in rodents. Whether they can be applied to clinical transplantation remains to be seen

  19. Irradiating strand material

    International Nuclear Information System (INIS)

    Austin, J.R.; Brown, M.J.; Loan, L.D.

    1975-01-01

    Conductors covered with insulation which is to be irradiated are passed between two groups of coaxial sheaves mounted rotatably individually. Successive sections of the conductors are advanced past the window of one accelerator head, around the associated sheave or sheaves, and then past the window of another accelerator head. The accelerators face in substantially opposite directions and are staggered along the paths of the conductors to avoid any substantial overlap of the electron beams associated therewith. The windows extend vertically to encompass all the generally horizontal passes of the conductors as between the two groups of sheaves. Preferably, conductors are strung-up between the sheaves in a modified figure eight pattern. The pattern is a figure eight modified to intermittently include a pass between the sheaves which is parallel to a line joining the axes of the two groups of sheaves. This reverses the direction of travel of the conductors and optimizes the uniformity of exposure of the cross sectional area of the insulation of the conductors to irradiation. The use of a figure eight path for the conductors causes the successive sections of the conductor to turn about the longitudinal axes thereof as they are advanced around the sheaves. In this way the insulation is more uniformly irradiated. In a preferred embodiment, twisted conductor pairs may be irradiated. The twist accentuates the longitudinal turning of the conductor pair. The irradiation of twisted pairs achieves obvious manufacturing economies while avoiding the necessity of having to twist irradiation cross-linked conductors

  20. Food irradiation in Japan

    International Nuclear Information System (INIS)

    Ito, Hitoshi

    1995-01-01

    The basic research on food irradiation in Japan was begun around 1955 by universities and national laboratories. In 1967, food irradiation was designated to the specific general research on atomic energy, and the national project on large scale was continued until 1983. As the result, the treatment of germination prevention for potatoes was approved by the Ministry of Health and Welfare in 1972. The Co-60 gamma ray irradiation facility of Shihoro Agricultural Cooperative is famous as the facility that succeeded in the practical use of food irradiation for the first time in the world. But the practical use of food irradiation stagnates and the research activities were reduced in Japan due to the circumstances thereafter. The effect of radiation to foods and living things is explained. The features of the radiation treatment of foods are small temperature rise, large transmissivity, no residue, the small loss of nutrition and large quantity, continuous treatment. The safety of irradiated foods is explained. The subjects for hereafter are discussed. (K.I.)

  1. The hypothalamo-pituitary-adrenal axis in major affective disorder

    DEFF Research Database (Denmark)

    Christensen, M V; Kessing, L V

    2001-01-01

    This paper reviews studies of the hypothalamo-pituitary-adrenal (HPA)-axis activity in patients with affective disorders. It is concluded that, despite methodological drawbacks in most studies, dysregulation of the HPA axis seems to be a consistent finding in a proportion of patients with affective...... disorder. The HPA axis is a complex neuroendocrine network with multiple integrated levels of control, and it is likely that the dysregulation involves abnormalities at several sites within the axis. At present, it is not clear whether the abnormalities are related to the affective episodes only...... or to the disorder itself. There is a need for prospective studies of larger samples of patients to be followed during successive affective episodes with a combination of measurements of the HPA-axis activity and brain imaging....

  2. Radiation and the hypothalamic-pituitary axis

    International Nuclear Information System (INIS)

    Littley, M.D.; Shalet, S.M.; Beardwell, C.G.

    1991-01-01

    This paper reports on radiation therapy which is an essential treatment in the management of many conditions. It is important to appreciate the high incidence of subsequent endocrine morbidity, however, if the hypothalamic pituitary region is within the radiation fields. This is very much more common with external radiation therapy than with other forms of radiation treatment. The dose and fractional of administered radiation are important determinants of the endocrine deficits, their time on onset, and severity. Irradiation of large volumes of brain and hypothalamus may increase the risk of hormonal abnormalities as may preceding surgery in the treatment of pituitary disease. The phenomena observed in children and adults illustrate that there may be damage to pituitary, hypothalamus, and higher centers. In patients who have received a significant radiation dose to the hypothalamic-pituitary region, regular follow-up is mandatory. In adults, surveillance will include pituitary function testing on an annual basis for at least 10 years. In children careful monitoring of growth and pubertal development and early treatment of radiation-induced GH deficiency are vital

  3. Diamond amorphization in neutron irradiation

    International Nuclear Information System (INIS)

    Nikolaenko, V.A.; Gordeev, V.G.

    1996-01-01

    The paper presents the results on neutron irradiation of the diamond in a nuclear reactor. It is shown that the neutron irradiation stimulates the diamond transition to the amorphous state. At a temperature below 750 o K the time required for the diamond-graphite transition decreases with decreasing irradiation temperature. On the contrary, in irradiation at higher temperatures the time of diamond conversion into the amorphous state increases with decreasing but always remains shorter than in the absence of irradiation. (author)

  4. Irradiated produce reaches Midwest market

    International Nuclear Information System (INIS)

    Pszczola, D.E.

    1992-01-01

    In March 1992, the Chicago-area store gave its shoppers a choice between purchasing irradiated and nonirradiated fruits. The irradiated fruits were treated at Vindicator Inc., the first U.S. food irradiation facility (starting up on January 10, 1992). The plant, located in Mulberry, Fla., then shipped the fruits in trucks to the store where they were displayed under a hand-lettered sign describing the irradiated fruits and showing the irradiation logo

  5. Detection methods for irradiated foods

    International Nuclear Information System (INIS)

    Dyakova, A.; Tsvetkova, E.; Nikolova, R.

    2005-01-01

    In connection with the ongoing world application of irradiation as a technology in Food industry for increasing food safety, it became a need for methods of identification of irradiation. It was required to control international trade of irradiated foods, because of the certain that legally imposed food laws are not violated; supervise correct labeling; avoid multiple irradiation. Physical, chemical and biological methods for detection of irradiated foods as well principle that are based, are introducing in this summary

  6. Blood irradiation: Rationale and technique

    International Nuclear Information System (INIS)

    Lewis, M.C.

    1990-01-01

    Upon request by the local American Red Cross, the Savannah Regional Center for Cancer Care irradiates whole blood or blood components to prevent post-transfusion graft-versus-host reaction in patients who have severely depressed immune systems. The rationale for blood irradiation, the total absorbed dose, the type of patients who require irradiated blood, and the regulations that apply to irradiated blood are presented. A method of irradiating blood using a linear accelerator is described

  7. food irradiation: activities and potentialities

    International Nuclear Information System (INIS)

    Doellstaedt, R.; Huebner, G.

    1985-01-01

    After the acceptance of food irradiation up to an overall average dose of 10 kGy recommended by the Joint FAO/IAEA/WHO Expert Committee on the Wholesomeness of Irradiated Food in October 1980, the G.D.R. started a programme for the development of techniques for food irradiation. A special onion irradiator was designed and built as a pilot plant for studying technological and economic parameters of the irradiation of onions. (author)

  8. Prevalence and comorbidity of Axis I and Axis II disorders among treatment refractory adolescents admitted for specialized psychotherapy

    NARCIS (Netherlands)

    Feenstra, D.J.; Busschbach, J.J.V.; Verheul, R.; Hutsebaut, J.

    2011-01-01

    Research shows that approximately half of the adolescents in a clinical setting suffer from a personality disorder (PD). This finding has not yet been replicated in Europe. To test whether this finding also applies to Europe, structured diagnostic interviews for both Axis I and Axis II disorders

  9. Correlation of RDC/TMD axis I diagnoses and axis II pain-related disability. A multicenter study

    NARCIS (Netherlands)

    Manfredini, D.; Ahlberg, J.; Winocur, E.; Guarda-Nardini, L.; Lobbezoo, F.

    2011-01-01

    As part of an ongoing multicenter investigation involving four highly specialized tertiary clinics for temporomandibular disorders (TMD) treatment, retrospective analysis of Research Diagnostic Criteria for TMD (RDC/TMD) axis I and axis II data gathered on clinic and community cases were assessed

  10. Energy Gleaning to Increase the Efficiency of 2-Axis Time-Position Tracking Photovoltaic Arrays Under Variably Cloudy Skies

    Science.gov (United States)

    Quinn, Stephanie White

    Positioning a photovoltaic (PV) array in the optimal orientation increases the collection of solar radiation and the production of electricity. Many methods for determining the optimal tilt angle of a fixed PV array have been reported in the literature; however, few methods have been proposed for finding the optimal tilt angle of a 2-axis time-position tracking PV array. This dissertation derives and validates a simple formula for directly calculating the optimal tilt angle of a 2-axis time-position tracking PV array under varying sky conditions. By modifying the conventional tilt angle as the sky conditions change, the tracking PV array can glean the additional small amounts of irradiation that are overlooked and unused on cloudy days. The validity of this formula was verified using 36 months of weather data from an installation in the northeastern United States where clear skies occur about 40% of the time. Simulations indicated that modifying the conventional tracking angles in response to changing cloud cover results in 2.26% increase in collected insolation and 2.33% increase in AC energy over a 36-month period when compared with conventional 2-axis time-position tracking. During hourly and sub-hourly intervals with cloud cover, the increase in energy collection can reach up to 50% more than for conventional 2-axis tracking. The ability to modify the conventional tracking angles in response to changing cloud cover allows the PV array to glean the previously uncollected energy, thereby capturing more of the total available irradiation and increasing electrical power production.

  11. Longevity of irradiated burros

    International Nuclear Information System (INIS)

    Lushbaugh, C.C.; Brown, D.G.; Frome, E.L.

    1986-01-01

    During the course of external radiation exposures of burros to establish a dose-response curve for acute mortality after total irradiation, some of the animals at the three lowest exposures to gamma photons survived. These groups of 10, 9, and 10 burros were exposed to 320, 425, and 545 R, respectively. There were 10 unirradiated controls. In 1953, 20 burros were exposed to 375 R (gamma) in 25-R/week increments without acute mortality and were added to the life-span study. In 1957, 33 burros were exposed to mixed neutron-gamma radiation from nuclear weapons, and 14 controls were added. The total number of irradiated burros in the study was increased to 88 by the addition of 6 animals irradiated with 180 rads of neutron and gamma radiation (4:1) in a Godiva-type reactor in 1959. In this experiment two acute deaths occurred which were not included in the analysis. In the first 4 years after the single gamma exposures, there were deaths from pancytopenia and thrombocytopenia, obviously related to radiation-induced bone-marrow damage. After that period, however, deaths were from common equine diseases; no death has resulted from a malignant neoplasm. Of the original 112 burros, 15 survive (10 irradiated and 5 controls). Survival curves determined for unirradiated and neutron-gamma- and gamma-irradiated burros showed significant differences. The mean survival times were: controls, 28 years; gamma irradiation only, 26 years; and neutron-gamma irradiation, 23 years. 3 refs., 4 figs., 1 tab

  12. Positive ion irradiation facility

    International Nuclear Information System (INIS)

    Braby, L.A.

    1985-01-01

    Many questions about the mechanisms of the response of cells to ionizing radiation can best be investigated using monoenergetic heavy charged particle beams. Questions of the role of different types of damage in the LET effect, for example, are being answered by comparing repair kinetics for damage induced by electrons with that produced by helium ions. However, as the models become more sophicated, the differences between models can be detected only with more precise measurements, or by combining high- and low-LET irradiations in split-dose experiments. The design of the authors present cell irradiation beam line has limited the authors to irradiating cells in a partial vacuum. A new way to mount the dishes and bring the beam to the cells was required. Several means of irradiating cells in mylar-bottom dishes have been used at other laboratories. For example at the RARAF Facility, the dual ion experiments are done with the dish bottom serving as the beam exit window but the cells are in a partial vacuum to prevent breaking the window. These researchers have chosen instead to use the dish bottom as the beam window and to irradiate the entire dish in a single exposure. A special, very fast pumping system will be installed at the end of the beam line. This system will make it possible to irradiate cells within two minutes of installing them in the irradiation chamber. In this way, the interaction of electron and ion-induced damage in Chlamydomonas can be studied with time between doses as short as 5 minutes

  13. Celiac axis stenosis: incidence and etiologies in asymptomatic individuals

    International Nuclear Information System (INIS)

    Park, Chang Min; Chung, Jin Wook; Kim, Hyun Beom; Shin, Sang June; Park, Jae Hyung

    2000-01-01

    To determine the incidence and etiologies of celiac axis stenosis in asymptomatic individuals. This prospective study involved 400 consecutive patients (male: 319, female: 81) referred to us for celiac arteriography between April and July 1999. When celiac axis branches were opacified by collateral circulation during superior mesenteric arteriography, the presence of celiac axis stenosis was suspected; lateral projection celiac arteriography was performed and the pressure gradient was measured. The indicators used to determine whether or not celiac axis stenosis was significant were luminal narrowing of more than 50% and a resultant pressure gradient of at least 10 mmHg. Its etiology was determined on the basis of angiographic appearances and CT findings. Twenty-nine patients (7.3%) had celiac axis stenosis. The etiology of the condition was extrinsic compression due to the median arcuate ligament in 16 patients (55%) and atherosclerosis in three (10%), while in ten (35%) it was not determined. The incidence of celiac axis stenosis did not vary significantly according to sex, age and the presence of calcified aortic plaque representing atherosclerosis. The incidence of hemodynamically significant celiac axis stenosis in this asymptomatic Korean population was 7.3% and the most important etiology was extrinsic compression by the median arcuate ligament of the diaphragm. Atherosclerosis was only a minor cause of the condition

  14. Gamma Irradiation does not Cause Carcinogenesis of Irradiated Herbs

    International Nuclear Information System (INIS)

    Thongphasuk, Jarunee; Thongphasuk, Piyanuch; Eamsiri, Jarurut; Pongpat, Suchada

    2009-07-01

    Full text: Microbial contamination of medicinal herbs can be effectively reduced by gamma irradiation. Since irradiation may cause carcinogenicity of the irradiated herbs, the objective of this research is to study the effect of gamma irradiation (10 and 25 kGy) from cobalt-60 on carcinogenicity. The herbs studied were Pueraria candollei Grah., Curcuma longa Linn. Zingiber montanum, Senna alexandrina P. Miller, Eurycoma Longifolia Jack, Gymnostema pentaphylum Makino, Ginkgo biloba, Houttuynia cordata T., Andrographis paniculata, Thunbergia laurifolia L., Garcinia atroviridis G., and Cinnamomum verum J.S.Presl. The results showed that gamma irradiation at the dose of 10 and 25 kGy did not cause carcinogenicity of the irradiated herbs

  15. Post-irradiation diarrhea

    International Nuclear Information System (INIS)

    Meerwaldt, J.H.

    1984-01-01

    In radiotherapy of pelvic cancers, the X-ray dose to be delivered to the tumour is limited by the tolerance of healthy surrounding tissue. In recent years, a number of serious complications of irradiation of pelvic organs were encountered. Modern radiotherapy necessitates the acceptance of a calculated risk of complications in order to achieve a better cure rate. To calculate these risks, one has to know the radiation dose-effect relationship of normal tissues. Of the normal tissues most at risk when treating pelvic tumours only the bowel is studied. In the literature regarding post-irradiation bowel complications, severe and mild complications are often mixed. In the present investigation the author concentrated on the group of patients with relatively mild symptoms. He studied the incidence and course of post-irradiation diarrhea in 196 patients treated for carcinoma of the uterine cervix or endometrium. The aims of the present study were: 1) to determine the incidence, course and prognostic significance of post-irradiation diarrhea; 2) to assess the influence of radiotherapy factors; 3) to study the relation of bile acid metabolism to post-irradiation diarrhea; 4) to investigate whether local factors (reservoir function) were primarily responsible. (Auth.)

  16. Irradiation creep of graphite

    International Nuclear Information System (INIS)

    Kennedy, C.R.

    1990-01-01

    Displacement damage of graphite by neutron irradiation causes graphite to change dimensions. This dimensional instability requires careful attention when graphite is used as as moderator and reflector material in nuclear devices. Natural gradients in flux and temperature result in time-varying differential growth generating stresses similar to thermal stresses with an ever increasing temperature gradient. Graphite, however, does have the ability to creep under irradiation, allowing the stress intensity to relax below the fracture strength of the material. Creep strain also serves to average the radiation-induced strains, thus contributing to the stability of the core. As the dimensional instability is a function of temperature, so are the creep characteristics of graphite, and it is of interest to generalize the available data for extension to more extreme conditions of fluence and temperature. Irradiation creep of graphite is characterized by two stages of creep; a primary stage that saturates with time and a secondary stage that is generally assumed to be linear and constant with time. Virtually all past studies have not considered primary creep in detail primarily because there is limited available data at the very low fluences required to saturate primary creep. It is the purpose of this study to carefully examine primary creep in detail over the irradiation temperature range of 150 to 1000 degree C. These studies also include the combined effects of creep, differential growth, and structural changes in graphite by irradiation. 3 refs., 5 figs

  17. irradiated gem stones

    International Nuclear Information System (INIS)

    Salama, S.S.M

    2006-01-01

    gem stones are those stones which have beauty that can be based on its color, transparency, brilliance (degree to which light is scattered) and the crystalline perfection (no minerals or other inclusions). topaz AL 2 SiO 4 (F,OH) 2 Aluminum fluoro-hydroxyl -silicate, it belongs to class silicates and subclass cyclo silicates and it is used mainly as gemstones, it is most common irradiated gem on the market. high energy such as neutrons, have enough energy to produce color centres .irradiation is most often carried out in nuclear reactors (high-energy neutrons). irradiation of topaz in the egyptian research reactor (ETRR-2) by neutrons changes its cloudy white color to a reddish pink which could be changed to blue by heating. nuclear reactions inside the irradiated stones produce radioisotopes. resulting to residual radioactivity. residual radioactivity is potentially a problem;therefore stones have to be stored in storage for a period of time to reduce the residual radioactivity aiming to reach the safety level of transportation. the storage time of the stones is dependent on trace element concentrations connected with their life-times in topaz . therefore, inspection of the trace elements in the stones and their half-life times are essential before irradiation

  18. ORNL irradiation creep facility

    International Nuclear Information System (INIS)

    Reiley, T.C.; Auble, R.L.; Beckers, R.M.; Bloom, E.E.; Duncan, M.G.; Saltmarsh, M.J.; Shannon, R.H.

    1980-09-01

    A machine was developed at ORNL to measure the rates of elongation observed under irradiation in stressed materials. The source of radiation is a beam of 60 MeV alpha particles from the Oak Ridge Isochronous Cyclotron (ORIC). This choice allows experiments to be performed which simulate the effects of fast neutrons. A brief review of irradiation creep and experimental constraints associated with each measurement technique is given. Factors are presented which lead to the experimental choices made for the Irradiation Creep Facility (ICF). The ICF consists of a helium-filled chamber which houses a high-precision mechanical testing device. The specimen to be tested must be thermally stabilized with respect to the temperature fluctuations imposed by the particle beam which passes through the specimen. Electrical resistance of the specimen is the temperature control parameter chosen. Very high precision in length measurement and temperature control are required to detect the small elongation rates relevant to irradiation creep in the test periods available (approx. 1 day). The apparatus components and features required for the above are presented in some detail, along with the experimental procedures. The damage processes associated with light ions are discussed and displacement rates are calculated. Recent irradiation creep results are given, demonstrating the suitability of the apparatus for high resolution experiments. Also discussed is the suitability of the ICF for making high precision thermal creep measurements

  19. [Localization and registration of the hinge axis in black Africans].

    Science.gov (United States)

    Assi, K D; N'Guessan, K S; N'Dindin, C; Bamba, A

    2003-06-01

    The study of the cinematic method using "SAM" and "Quick Axis of FAG" added to mandibular condyle palpation for the hinge axis limited points, show that the Black Africans mandibular condyle rotation axis position is higher (3.5 mm) and backer (2 mm) than the Caucasians. The axial points are located to between 11 and 12 mm in front of the tragus and between 7 and 8 mm below on the perpendicular line to the furrow defining the tragus superior side to the Ectocanthus.

  20. Thoughts on the so-called radius-capitellum axis

    Energy Technology Data Exchange (ETDEWEB)

    Schild, H.; Mueller, H.A.; Wagner, H.; Baetz, W.

    1982-02-01

    We have studied 438 patients radiologically in order to observe the so-called 'radius-capitellum axis'. In about a quarter of people with normal elbows the axis passes lateral to the middle portion of the capitellum, so that even when there is marked deviation, there is no certainty that the humero-radial joint is abnormal. Deviation of the axis can be caused by changes in the shape of the capitellum or of the radius, or by distension of the capsule of the elbow joint, or by various changes in muscular pull.

  1. Rates and processes of crystallization in on-axis and off-axis MOR basaltic melts

    Science.gov (United States)

    Zellmer, Georg F.; Dulski, Peter; Iizuka, Yoshiyuki; Perfit, Michael R.

    2012-12-01

    Residence times of olivine and plagioclase phenocrysts and xenocrysts in mid-ocean ridge (MOR) basaltic melts have been studied since the mid 1980s using geospeedometric techniques (i.e. using diffusion of major and trace elements) in order to constrain the processes of melt ascent and differentiation in this important magmatic setting. Residence times range from a few hours to several years, but potential links between these timescales and specific tectonomagmatic variables such as spreading rate and relative locations of eruption site and ridge axis have remained elusive. Here we demonstrate how incomplete chemical diffusion of Sr within plagioclase crystals from MOR basalts erupted in on- and off-axis settings on a number of ridges with variable spreading rates provide geospeedometric constraints. We combine electron probe microanalytical crystal maps with detailed laser ablation profiles of almost 70 plagioclase crystals from the fast spreading East Pacific Rise (EPR) at 9-10°N, the intermediate spreading Gorda and Juan de Fuca (JdF) ridges, and the ultraslow spreading Gakkel ridge to calculate crystal residence times. These range from a few days to several months. The scarcity of residence times exceeding years corroborates previous data indicating that most of the growth of plagioclase phenocrysts occurs within the conduit at the onset of and during eruption on the sea floor, and extends this result to the fast-spreading EPR. Further, statistical analysis is employed to show for the first time that residence times are systematically longer at slower spreading rates, in off-axis samples, and samples sourced from laterally distal axial melt lenses. Plagioclase textures and residence time variations appear to be linked to differences in the dynamics of late-stage, pre-eruptive magma storage and ascent in the different tectonomagmatic settings investigated. In the future, geospeedometric work on MOR samples will be required to assess if the effect of spreading

  2. Food irradiation - general aspects

    International Nuclear Information System (INIS)

    Ley, F.J.

    1985-01-01

    This paper describes research and development experience in food irradiation followed by commercial utilisation of multi-purpose plants. The main design objectives should be high efficiency and uniform dose. Particular care must be given to dosimetry and the use of plastic dosimeters is described. Capital outlay for a 1 MCi Cobalt 60 irradiator is estimated to be 2.5 million dollars giving a unit processing cost of 0.566 dollars/ft 3 of throughput for 8000 hour/year use at a dose of 25 kGy. (2.5 Mrad). The sale of irradiated food for human consumption in Britain is not yet permitted but it is expected that enabling legislation will be introduced towards the end of 1985

  3. The Birmingham Irradiation Facility

    International Nuclear Information System (INIS)

    Dervan, P.; French, R.; Hodgson, P.; Marin-Reyes, H.; Wilson, J.

    2013-01-01

    At the end of 2012 the proton irradiation facility at the CERN PS will shut down for two years. With this in mind, we have been developing a new ATLAS scanning facility at the University of Birmingham Medical Physics cyclotron. With proton beams of energy approximately 30 MeV, fluences corresponding to those of the upgraded Large Hadron Collider (HL-LHC) can be reached conveniently. The facility can be used to irradiate silicon sensors, optical components and mechanical structures (e.g. carbon fibre sandwiches) for the LHC upgrade programme. Irradiations of silicon sensors can be carried out in a temperature controlled cold box that can be scanned through the beam. The facility is described in detail along with the first tests carried out with mini (1×1 cm 2 ) silicon sensors

  4. The Birmingham Irradiation Facility

    Energy Technology Data Exchange (ETDEWEB)

    Dervan, P. [The University of Liverpool, Department of Physics (United Kingdom); French, R.; Hodgson, P. [The University of Sheffield, Department of Physics and Astronomy (United Kingdom); Marin-Reyes, H., E-mail: h.marin-reyes@sheffield.ac.uk [The University of Sheffield, Department of Physics and Astronomy (United Kingdom); Wilson, J. [The University of Birmingham, School of Physics and Astronomy (United Kingdom)

    2013-12-01

    At the end of 2012 the proton irradiation facility at the CERN PS will shut down for two years. With this in mind, we have been developing a new ATLAS scanning facility at the University of Birmingham Medical Physics cyclotron. With proton beams of energy approximately 30 MeV, fluences corresponding to those of the upgraded Large Hadron Collider (HL-LHC) can be reached conveniently. The facility can be used to irradiate silicon sensors, optical components and mechanical structures (e.g. carbon fibre sandwiches) for the LHC upgrade programme. Irradiations of silicon sensors can be carried out in a temperature controlled cold box that can be scanned through the beam. The facility is described in detail along with the first tests carried out with mini (1×1 cm{sup 2}) silicon sensors.

  5. The Birmingham Irradiation Facility

    Science.gov (United States)

    Dervan, P.; French, R.; Hodgson, P.; Marin-Reyes, H.; Wilson, J.

    2013-12-01

    At the end of 2012 the proton irradiation facility at the CERN PS [1] will shut down for two years. With this in mind, we have been developing a new ATLAS scanning facility at the University of Birmingham Medical Physics cyclotron. With proton beams of energy approximately 30 MeV, fluences corresponding to those of the upgraded Large Hadron Collider (HL-LHC) can be reached conveniently. The facility can be used to irradiate silicon sensors, optical components and mechanical structures (e.g. carbon fibre sandwiches) for the LHC upgrade programme. Irradiations of silicon sensors can be carried out in a temperature controlled cold box that can be scanned through the beam. The facility is described in detail along with the first tests carried out with mini (1×1 cm2) silicon sensors.

  6. The Birmingham Irradiation Facility

    CERN Document Server

    Dervan, P; Hodgson, P; Marin-Reyes, H; Wilson, J

    2013-01-01

    At the end of 2012 the proton irradiation facility at the CERN PS [1] will shut down for two years. With this in mind, we have been developing a new ATLAS scanning facility at the University of Birmingham Medical Physics cyclotron. With proton beams of energy approximately 30 MeV, fluences corresponding to those of the upgraded Large Hadron Collider (HL-LHC) can be reached conveniently. The facility can be used to irradiate silicon sensors, optical components and mechanical structures (e.g. carbon fibre sandwiches) for the LHC upgrade programme. Irradiations of silicon sensors can be carried out in a temperature controlled cold box that can be scanned through the beam. The facility is described in detail along with the first tests carried out with mini (1 x 1 cm^2 ) silicon sensors.

  7. Neutron irradiation of seeds

    International Nuclear Information System (INIS)

    1967-01-01

    Neutrons are a valuable type of ionizing radiation for seed irradiation and radiobiological studies and for inducing mutations in crop plants. In experiments where neutrons are used in research reactors for seed irradiation it is difficult to measure the dose accurately and therefore to establish significant comparisons between experimental results obtained in various reactors and between repeated experiments in the same reactor. A further obstacle lies in the nature and response of the seeds themselves and the variety of ways in which they are exposed in reactors. The International Atomic Energy Agency decided to initiate international efforts to improve and standardize methods of exposing seeds in research reactors and of measuring and reporting the neutron dose. For this purpose, an International Neutron Seed Irradiation Programme has been established. The present report aims to give a brief but comprehensive picture of the work so far done in this programme. Refs, figs and tabs

  8. Energy and food irradiation

    International Nuclear Information System (INIS)

    Brynjolfsson, A.

    1978-01-01

    The energy used in food systems in the US amounts to about 16.5% of total US energy. An analysis has been made of the energy used in the many steps of the food-irradiation process. It is found that irradiation pasteurization uses only 21kJ/kg and radappertization 157kJ/kg, which is much less than the energy used in the other food processes. A comparison has also been made with other methods of preserving, distributing and preparing the meat for servings. It is found that the food irradiation can save significant amounts of energy. In the case of heat-sterilized and radiation-sterilized meats the largest fraction of the energy is used in the packaging, while in the frozen meats the largest energy consumption is by refrigeration in the distribution channels and in the home. (author)

  9. Food preservation by irradiation

    International Nuclear Information System (INIS)

    Kooij, J. van

    1981-01-01

    Twenty-five years of development work on the preservation of food by irradiation have shown that this technology has the potential to reduce post-harvest losses and to produce safe foods. The technological feasibility has been established but general acceptance of food irradiation by national regulatory bodies and consumers requires attention. The positive aspects of food preservation by irradiation include: the food keeps its freshness and its physical state, agents which cause spoilage (bacteria, etc.) are eliminated, recontamination does not take place, provided packaging materials are impermeable to bacteria and insects. It inhibits sprouting of root crops, kills insects and parasites, inactivates bacteria, spores and moulds, delays ripening of fruit, improves the technological properties of food. It makes foods biologically safe, allows the production of shelf-stable foods and is excellent for quarantine treatment, and generally improves food hygiene. The dose ranges needed for effective treatment are given

  10. Irradiation of food

    International Nuclear Information System (INIS)

    MacGregor, J.; Stanbrook, I.; Shersby, M.

    1989-01-01

    The House of Commons was asked to support the Government's intention to allow the use of the irradiation of foodstuffs under conditions that will fully safeguard the interests of the consumer. The Government, it was stated, regards this process as a useful additional way to ensure food safety. The effect of the radiation in killing bacteria will enhance safety standards in poultry meat, in some shell-fish and in herbs and spices. The problem of informing the public when the food has been irradiated, especially as there is no test to detect the irradiation, was raised. The subject was debated for an hour and a half and is reported verbatim. The main point raised was over whether the method gave safer food as not all bacteria were killed in the process. The motion was carried. (U.K.)

  11. Food preservation by irradiation

    International Nuclear Information System (INIS)

    Gottschalk, M.

    1978-01-01

    In November, 1977, an International Symposium on Food Preservation by Irradiation was held at Wageningen, the Netherlands. About 200 participants attended the Symposium which was organised by the International Atomic Energy Agency, the Food and Agriculture Organization of the United Nations and the World Health Organization; a reflection of the active interest which is being shown in food irradiation processing, particularly among developing countries. The 75 papers presented provided an excellent review of the current status of food irradiation on a wide range of different topics, and the Symposium also afforded the valuable opportunity for informal discussion among the participants and for developing personal contacts. A brief survey of the salient aspects discussed during the course of the meeting are reported on. (orig.) [de

  12. Studies of blood irradiator application

    International Nuclear Information System (INIS)

    Li Wenhong; Lu Yangqiao

    2004-01-01

    Transfusion is an important means for medical treatment, but it has many syndromes such as transfusion-associated graft-versus-host disease, it's occurrence rate of 5% and above 90% death-rate. Now many experts think the only proven method is using blood irradiator to prevent this disease. It can make lymphocyte of blood product inactive, so that it can not attack human body. Therefore, using irradiation blood is a trend, and blood irradiator may play an important role in medical field. This article summarized study of blood irradiator application, including the meaning of blood irradiation, selection of the dose for blood irradiation and so on

  13. Design characteristics to reduce inadvertent cross-axis coupling during side stick handling of aircraft pitch and roll axis control

    Science.gov (United States)

    Cote, Marie-Eve

    Integrating a manual flight control inceptor with coupled axes such as the side stick within a flight deck creates challenges for the pilot to input a one-axis command without inadvertently inducing inputs in the opposite axis. The present paper studies three design features of the side stick and armrest setup believed to help reduce inadvertent cross-axis coupling occurrences. Design features address the aimed pilot population anthropometry (1.57m woman to 1.9m male) and their variability in upper segment measurements. Seven pilots of varying anthropometric sizes were asked to perform one-axis manoeuvres in pitch and roll for each setup configuration. To compare the setups both the duration and the definite integral of the unintended cross-axis input were processed and analyzed for each manoeuvre. Findings show that a short armrest reduces the occurrences of cross-axis input for the roll manoeuvre, whereas the side stick skew reduces inadvertent cross-axis coupling for the pitch manoeuvres.

  14. Solar irradiation over Zambia

    International Nuclear Information System (INIS)

    Jain, P.C.

    1983-11-01

    Angstroem-Page linear regression equation between global irradiation and sunshine duration is fitted for five Zambian locations for which the direct measured values of the global irradiation exist. Excellent correlation is found to exist for all the five places. The values of the correlation coefficients for Lusaka, Livingstone, Ndola, Mansa and Mongu are found to be 0.99, 0.99, 0.98, 0.97 and 0.95, respectively, and the values of the regression coefficients (a,b) are (0.191, 0.534), (0.177, 0.638), (0.253, 0.434), (0.270, 0.483) and (0.235, 0.506), respectively. The regression coefficients are observed to vary with the elevation of the station above sea level. A linear relationship between the elevation and the coefficient a and a quadratic relationship between the elevation and the coefficient b is assumed and is used to estimate the values of the regression coefficients for 14 other stations in the country. Using the estimated values of the coefficients and the measured values of the sunshine duration, estimates of the global irradiation have been made for these locations. No data for the diffuse irradiation is available. The estimates for diffuse irradiation have been made for all the 19 locations using the expression Hsub(D)=H(0.754-0.654 S/S 0 ) used by Lewis, Solar Energy, 31, no. 1, 125-128 (1983), for estimating diffuse irradiation in Zimbabwean locations. (author)

  15. Facts about food irradiation: Nutritional quality of irradiated foods

    International Nuclear Information System (INIS)

    1991-01-01

    This fact sheet briefly considers the nutritional value of irradiated foods. Micronutrients, especially vitamins, are sensitive to any food processing method, but irradiation does not cause any special nutritional problems in food. 4 refs

  16. The Birmingham Irradiation Facility

    OpenAIRE

    French, R.S; Hodgson, P; Marin-Reyes, H

    2013-01-01

    At the end of 2012 the proton irradiation facility at the CERN PS [1] will shut down for two years. With this in mind, we have been developing a new ATLAS scanning facility at the University of Birmingham Medical Physics cyclotron. With proton beams of energy approximately 30 MeV, fluences corresponding to those of the upgraded large Hadron Collider (HL-LHC) can be reached conveniently. The facility can be used to irradiate silicon sensors, optical components and mechanical structures (e.g. ca...

  17. The Birmingham Irradiation Facility

    OpenAIRE

    Dervan, P.; French, R.; Hodgson, P.; Marin-Reyes, H.; Wilson, J.

    2013-01-01

    At the end of 2012 the proton irradiation facility at the CERN PS [1] will shut down for two years. With this in mind, we have been developing a new ATLAS scanning facility at the University of Birmingham Medical Physics cyclotron. With proton beams of energy approximately 30 MeV, fluences corresponding to those of the upgraded Large Hadron Collider (HL-LHC) can be reached conveniently. The facility can be used to irradiate silicon sensors, optical components and mechanical structures (e.g. c...

  18. Canadian Irradiation Centre

    International Nuclear Information System (INIS)

    1987-05-01

    The Canadian Irradiation Centre is a non-profit cooperative project between Atomic Energy of Canada Limited, Radiochemical Company and Universite du Quebec, Institut Armand-Frappier, Centre for Applied Research in Food Science. The Centre's objectives are to develop, demonstrate and promote Canada's radiation processing technology and its applications by conducting applied research; training technical, professional and scientific personnel; educating industry and government; demonstrating operational and scientific procedures; developing processing procedures and standards, and performing product and market acceptance trials. This pamphlet outlines the history of radoation technology and the services offered by the Canadian Irradiation Centre

  19. Microstructure of irradiated materials

    International Nuclear Information System (INIS)

    Robertson, I.M.

    1995-01-01

    The focus of the symposium was on the changes produced in the microstructure of metals, ceramics, and semiconductors by irradiation with energetic particles. the symposium brought together those working in the different material systems, which revealed that there are a remarkable number of similarities in the irradiation-produced microstructures in the different classes of materials. Experimental, computational and theoretical contributions were intermixed in all of the sessions. This provided an opportunity for these groups, which should interact, to do so. Separate abstracts were prepared for 58 papers in this book

  20. Fuel or irradiation subassembly

    International Nuclear Information System (INIS)

    Seim, O.S.; Hutter, E.

    1975-01-01

    A subassembly for use in a nuclear reactor is described which incorporates a loose bundle of fuel or irradiation pins enclosed within an inner tube which in turn is enclosed within an outer coolant tube and includes a locking comb consisting of a head extending through one side of the inner sleeve and a plurality of teeth which extend through the other side of the inner sleeve while engaging annular undercut portions in the bottom portion of the fuel or irradiation pins to prevent movement of the pins

  1. Economics of food irradiation

    International Nuclear Information System (INIS)

    Kunstadt, P.; Steeves, C.; Beaulieu, D.

    1993-01-01

    The number of products being radiation processed worldwide is constantly increasing and today includes such diverse items as medical disposables, fruits and vegetables, spices, meats, seafoods and waste products. This range of products to be processed has resulted in a wide range of irradiator designs and capital and operating cost requirements. This paper discusses the economics of low dose food irradiation applications and the effects of various parameters on unit processing costs. It provides a model for calculating specific unit processing costs by correlating known capital costs with annual operating costs and annual throughputs. It is intended to provide the reader with a general knowledge of how unit processing costs are derived. (author)

  2. Irradiated cocoa beans

    International Nuclear Information System (INIS)

    Ashby, R.; Tesh, J.M.

    1982-11-01

    Groups of 40 male and 40 female CD rats were fed powdered rodent diet containing 25% (w/w) of either non-irradiated, irradiated or fumigated cocoa beans. The diets were supplemented with certain essential dietary constituents designed to satisfy normal nutritional requirements. An additional 40 male and 40 female rats received basal rodent diet alone (ground) and acted as an untreated control. After 70 days of treatment, 15 male and 15 female rats from each group were used to assess reproductive function of the F 0 animals and growth and development of the F 1 offspring up to weaning; the remaining animals were killed after 91 days of treatment. (orig.)

  3. Microstructure evolution during irradiation

    International Nuclear Information System (INIS)

    Robertson, I.M.; Was, G.S.; Hobbs, L.W.; Diaz de la Rubia, T.

    1997-01-01

    The symposium focused on the microstructural changes produced in semiconductors, metals, ceramics and polymers by irradiation with energetic particles. The symposium provided an opportunity to bring together those working in different materials systems and revealed that there are a remarkable number of similarities in the changes produced by irradiation in the different classes of materials. Experimental, computational and theoretical contributions were intermixed throughout the sessions, which provided an opportunity for these groups to interact. Separate abstracts were prepared for most papers in this volume

  4. Half body irradiation

    International Nuclear Information System (INIS)

    Bartelink, H.; Battermann, J.; Hart, G.

    1980-01-01

    Twenty-one patients with complaints of severe pain from disseminated breast cancer were treated with half body irradiation with a single dose of 600 to 800 rad. All of them had a relief of pain for periods ranging from 14 to 280 days, with a median duration of 101 days. The objective effects of a single radiation dose was studied in 15 patients with lung metastases. The growth delay observed in these patients was of the same order as the period of pain relief observed in breast cancer patients after half body irradiation. In general a longer lasting palliation was obtained in patients with slowly growing tumors

  5. Particle orbit analysis for LHD helical axis configurations

    International Nuclear Information System (INIS)

    Guasp, J.; Yamazaki, K.; Motojima, O.

    1993-04-01

    Fast ion orbits for helical magnetic axis configurations in LHD (Large Helical Device) are analyzed and compared with the standard circular axis case. Boundaries between passing and helically trapped particle regions show clear differences: in the non-planar axis case the helically trapped region spreads, near the magnetic axis, over a much wider band across the 90deg pitch angle value and shows a very marked asymmetry. The locally trapped particle region is also wider than in the standard case. The differences in the loss cone boundaries of the two cases are rather small, however, the effects of re-entering criteria are very important in both cases. On the contrary, effects of finite coil size are not significant. (author)

  6. Tilted-axis wobbling in odd-mass nuclei

    Science.gov (United States)

    Budaca, R.

    2018-02-01

    A triaxial rotor Hamiltonian with a rigidly aligned high-j quasiparticle is treated by a time-dependent variational principle, using angular momentum coherent states. The resulting classical energy function has three unique critical points in a space of generalized conjugate coordinates, which can minimize the energy for specific ordering of the inertial parameters and a fixed angular momentum state. Because of the symmetry of the problem, there are only two unique solutions, corresponding to wobbling motion around a principal axis and, respectively, a tilted axis. The wobbling frequencies are obtained after a quantization procedure and then used to calculate E 2 and M 1 transition probabilities. The analytical results are employed in the study of the wobbling excitations of 135Pr nucleus, which is found to undergo a transition from low angular momentum transverse wobbling around a principal axis toward a tilted-axis wobbling at higher angular momentum.

  7. Off-axis vortex breakdown in a shallow whirlpool.

    Science.gov (United States)

    Herrada, Miguel A; Shtern, Vladimir N; López-Herrera, José María

    2013-06-01

    The off-axis emergence of vortex breakdown (VB) is revealed. The steady axisymmetric flow in a vertical sealed cylinder, which is partially filled with water and the rest is filled with air, is driven by the rotating bottom disk. The numerical simulations show that VB can emerge away from the rotation axis, interface, and walls. As the rotation intensifies, VB first develops in the water region. If the water height is less (larger) than nearly one half of the cylinder radius, VB emerges off (on) the axis. As the rotation further increases, the off-axis VB ring touches the interface and then a thin countercirculation layer develops in the air flow above the water VB domain. This two-fluid VB ring shrinks (it even disappears in a very shallow whirlpool) as the interface approaches the bottom disk.

  8. Space/Flight Operable Miniature Six Axis Transducer, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — FUTEK will fully design and manufacture a sensor capable of measuring forces in and about each axis. The unit will measure forces up to 300 Newton's in the principle...

  9. The effects of lateral head tilt on ocular astigmatic axis

    Directory of Open Access Journals (Sweden)

    Hamid Fesharaki

    2014-01-01

    Conclusion: Any minimal angle of head tilt may cause erroneous measurement of astigmatic axis and should be avoided during refraction. One cannot rely on the compensatory function of ocular counter-torsion during the refraction.

  10. Determination of Elastic Twist in Horizontal Axis Wind Turbines (HAWTs)

    Energy Technology Data Exchange (ETDEWEB)

    Stoddard, F.; Nelson, V.; Starcher, K.; Andrews, B.

    2006-06-01

    This report presents the results of a project at the Alternative Energy Institute (AEI) which measured and calculated the elastic twist of three representative composite horizontal-axis blades: Carter 300, Gougeon ESI 54, and UTRC 8 kW.

  11. UARS PEM Level 2 AXIS 1 V001

    Data.gov (United States)

    National Aeronautics and Space Administration — The UARS Particle Environment Monitor (PEM) level 2 Atmosphere X-Ray Imaging Spectrometer (AXIS) unit 1 daily product contains the X-ray high-resolution spectral...

  12. UARS PEM Level 2 AXIS 2 V001

    Data.gov (United States)

    National Aeronautics and Space Administration — The UARS Particle Environment Monitor (PEM) level 2 Atmosphere X-Ray Imaging Spectrometer (AXIS) unit 2 daily product contains the X-ray high-resolution spectral...

  13. Design of a Three-Axis Machine Tool Module

    National Research Council Canada - National Science Library

    Childers, Marshal

    2003-01-01

    This report documents the design improvement process of the components in a tool module for a three-axis machine tool, which occurred during the period of March-April 2002 in support of a critical U.S...

  14. Stress and the HPA Axis: Balancing Homeostasis and Fertility

    Directory of Open Access Journals (Sweden)

    Dana N. Joseph

    2017-10-01

    Full Text Available An organism’s reproductive fitness is sensitive to the environment, integrating cues of resource availability, ecological factors, and hazards within its habitat. Events that challenge the environment of an organism activate the central stress response system, which is primarily mediated by the hypothalamic–pituitary–adrenal (HPA axis. The regulatory functions of the HPA axis govern the cardiovascular and metabolic system, immune functions, behavior, and reproduction. Activation of the HPA axis by various stressors primarily inhibits reproductive function and is able to alter fetal development, imparting a biological record of stress experienced in utero. Clinical studies and experimental data indicate that stress signaling can mediate these effects through direct actions in the brain, gonads, and embryonic tissues. This review focuses on the mechanisms by which stress activation of the HPA axis impacts fertility and fetal development.

  15. Stress and the HPA Axis: Balancing Homeostasis and Fertility.

    Science.gov (United States)

    Joseph, Dana N; Whirledge, Shannon

    2017-10-24

    An organism's reproductive fitness is sensitive to the environment, integrating cues of resource availability, ecological factors, and hazards within its habitat. Events that challenge the environment of an organism activate the central stress response system, which is primarily mediated by the hypothalamic-pituitary-adrenal (HPA) axis. The regulatory functions of the HPA axis govern the cardiovascular and metabolic system, immune functions, behavior, and reproduction. Activation of the HPA axis by various stressors primarily inhibits reproductive function and is able to alter fetal development, imparting a biological record of stress experienced in utero. Clinical studies and experimental data indicate that stress signaling can mediate these effects through direct actions in the brain, gonads, and embryonic tissues. This review focuses on the mechanisms by which stress activation of the HPA axis impacts fertility and fetal development.

  16. Dual Axis Controller for Extreme Environments, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The Dual Axis Controller for Extreme Environments (DACEE) addresses a critical need of NASA's future exploration plans to investigate extreme environments within our...

  17. Three-Axis Gasless Sounding Rocket Payload Attitude Control

    Data.gov (United States)

    National Aeronautics and Space Administration — Gas released by current sounding rocket payload attitude control systems (ACS) has the potential to interfere with some types of science instruments. A single-axis...

  18. Consumer opinions in Argentina on food irradiation: irradiated onions

    International Nuclear Information System (INIS)

    Curzio, O.A.; Croci, C.A.

    1998-01-01

    Two surveys were carried out in Buenos Aires of consumer attitudes towards irradiated onions [no data given]. The first investigated the general level of consumer knowledge concerning food irradiation, whilst the second (which covered consumers who had actually bought irradiated onions) examined reasons for purchase and consumer satisfaction. Results reveal that more than 90% of consumers surveyed had a very limited knowledge of food irradiation

  19. Comparison of Pyranometers and Reference Cells on Fixed and One-axis Tracking Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Dooraghi, Michael R [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Sengupta, Manajit [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Vignola, Frank [University of Oregon; Peterson, Josh [University of Oregon; Mavromatakis, Fotis [Technological Educational Institute of Crete; Chiu, Chun-Yu [University of Oregon

    2017-10-12

    Photovoltaic (PV) system perfomance is monitored by a wide variety of sensors. These instruments range from secondary standard pyranometers to photodiode-based pyranometers to reference cells. Although instruments are mounted in the plane of array of the modules a wide range of results have been obtained. Some of these difference have been assumed to come from systematic uncertainties associated with the irradiance sensors. This study is an attempt to quantify these differences by comparing the output of selected thermopile-based pyranometers to photodiode-based pyranometers and reference cells on a horizontal surface, a fixed-tilt surface, and a one-axis tracking surface. This analysis focuses on clear-sky results from two sites with different climatic conditions. Several important features were observed. Photodiode-based pyranometers and reference cells produce widely different results under clear skies, especially at larger angles-of-incidence even though both instruments are based on measuring the short circuit current of solar cells. The difference is caused by the scattering of light as it passes through the glazing of the reference cell or the diffuser lens of the photodioded- base pyranometer. Both instruments are shown to have similar response to the spectral distribution of the irradiance when compared to the thermopile-based pyranometer that has a response nearly independent of the wavelength of light used by PV modules.

  20. Early programming of the IGF-I axis

    DEFF Research Database (Denmark)

    Larnkjær, Anni; Ingstrup, Helga Kristensen; Schack-Nielsen, Lene

    2009-01-01

    -I production. Conversely, studies suggest that later in childhood, those breastfed are taller and have higher IGF-I levels. Therefore, it has been suggested that the IGF-I axis may be programmed by diet during infancy. The association between IGF-I in infancy and later life is not known. OBJECTIVE: To examine......=-0.26, P=0.043, and n=109). CONCLUSION: The results support the hypothesis that the IGF-I axis can be programmed early in life....

  1. Mechanical and irradiation properties of zirconium alloys irradiated in HANARO

    International Nuclear Information System (INIS)

    Kwon, Oh Hyun; Eom, Kyong Bo; Kim, Jae Ik; Suh, Jung Min; Jeon, Kyeong Lak

    2011-01-01

    These experimental studies are carried out to build a database for analyzing fuel performance in nuclear power plants. In particular, this study focuses on the mechanical and irradiation properties of three kinds of zirconium alloy (Alloy A, Alloy B and Alloy C) irradiated in the HANARO (High-flux Advanced Neutron Application Reactor), one of the leading multipurpose research reactors in the world. Yield strength and ultimate tensile strength were measured to determine the mechanical properties before and after irradiation, while irradiation growth was measured for the irradiation properties. The samples for irradiation testing are classified by texture. For the irradiation condition, all samples were wrapped into the capsule (07M-13N) and irradiated in the HANARO for about 100 days (E > 1.0 MeV, 1.1 10 21 n/cm 2 ). These tests and results indicate that the mechanical properties of zirconium alloys are similar whether unirradiated or irradiated. Alloy B has shown the highest yield strength and tensile strength properties compared to other alloys in irradiated condition. Even though each of the zirconium alloys has a different alloying content, this content does not seem to affect the mechanical properties under an unirradiated condition and low fluence. And all the alloys have shown the tendency to increase in yield strength and ultimate tensile strength. Transverse specimens of each of the zirconium alloys have a slightly lower irradiation growth tendency than longitudinal specimens. However, for clear analysis of texture effects, further testing under higher irradiation conditions is needed

  2. Optic axis-driven new horizons for hyperbolic metamaterials

    Directory of Open Access Journals (Sweden)

    Boardman Allan D.

    2015-01-01

    Full Text Available The broad assertion here is that the current hyperbolic metamaterial world is only partially served by investigations that incorporate only some limited version of anisotropy. Even modest deviations of the optic axis from the main propagation axis lead to new phase shifts, which not only compete with those created by absorption but end up dominating them. Some progress has been attempted in the literature by introducing the terms “asymmetric hyperbolic media”, but it appears that this kind of asymmetry only involves an optic axis at an angle to the interface of a uniaxial crystal. From a device point of view, many new prospects should appear and the outcomes of the investigations presented here yield a new general theory. It is emphasised that the orientation of the optic axis is a significant determinant in the resulting optical properties. Whereas for conventional anisotropic waveguides homogeneous propagating waves occur over a limited range of angular dispositions of the optic axis it is shown that for a hyperbolic guide a critical angular setting exists, above which the guided waves are always homogeneous. This has significant implications for metawaveguide designs. The resulting structures are more tolerant to optic axis misalignment.

  3. Comparison of astigmatic axis in the seated and supine positions.

    Science.gov (United States)

    Smith, E M; Talamo, J H; Assil, K K; Petashnick, D E

    1994-01-01

    Refractive error is assessed in the seated position while keratorefractive procedures are performed in the supine position. Since position-induced ocular torsion could yield suboptimal results from improper axis alignment, this study was undertaken to ascertain whether ocular cyclotorsion occurs when a subject moves from a seated to supine position. Fifty eyes of 29 subjects with refractive cylinder greater than 0.50 diopters were enrolled. Refraction was done with a phoropter and the correction was placed in a trial frame using plus cylinder. Astigmatic axis was determined in the seated and supine positions for 32 eyes by utilizing the "rocking the cylinder" technique and for 32 eyes using the Jackson cross cylinder. Both techniques were used for 14 eyes. No statistically-significant difference for cylinder axis measured in the seated versus supine position was observed using the rocking the cylinder (4.3 degrees standard deviation [SD], 3.5 degrees, range 0 degrees to 13 degrees, p = NS) or the Jackson cross cylinder methods (2.3 degrees, SD, 1.9 degrees, range 0 degrees to 7 degrees, p = NS). Approximately 25% of eyes had a change in axis of 7 degrees to 16 degrees. These data suggest that the cylinder axis does not change significantly or predictably when most subjects move from the seated to supine position. The Jackson cross cylinder method seems more accurate and reproducible than the rocking the cylinder technique in determination of astigmatic axis under these circumstances.

  4. Design and optimize of 3-axis filament winding machine

    Science.gov (United States)

    Quanjin, Ma; Rejab, M. R. M.; Idris, M. S.; Bachtiar, B.; Siregar, J. P.; Harith, M. N.

    2017-10-01

    Filament winding technique is developed as the primary process for composite cylindrical structures fabrication at low cost. Fibres are wound on a rotating mandrel by a filament winding machine where resin impregnated fibres pass through a pay-out eye. This paper aims to develop and optimize a 3-axis, lightweight, practical, efficient, portable filament winding machine to satisfy the customer demand, which can fabricate pipes and round shape cylinders with resins. There are 3 main units on the 3-axis filament winding machine, which are the rotary unit, the delivery unit and control system unit. Comparison with previous existing filament winding machines in the factory, it has 3 degrees of freedom and can fabricate more complex shape specimens based on the mandrel shape and particular control system. The machine has been designed and fabricated on 3 axes movements with control system. The x-axis is for movement of the carriage, the y-axis is the rotation of mandrel and the z-axis is the movement of the pay-out eye. Cylindrical specimens with different dimensions and winding angles were produced. 3-axis automated filament winding machine has been successfully designed with simple control system.

  5. Self-starting aerodynamics analysis of vertical axis wind turbine

    Directory of Open Access Journals (Sweden)

    Jianyang Zhu

    2015-12-01

    Full Text Available Vertical axis wind turbine is a special type of wind-force electric generator which is capable of working in the complicated wind environment. The self-starting aerodynamics is one of the most important considerations for this kind of turbine. This article aims at providing a systematic synthesis on the self-starting aerodynamic characteristics of vertical axis wind turbine based on the numerical analysis approach. First, the physical model of vertical axis wind turbine and its parameter definitions are presented. Secondary, the interaction model between the vertical axis wind turbine and fluid is developed by using the weak coupling approach; the numerical data of this model are then compared with the wind tunnel experimental data to show its feasibility. Third, the effects of solidity and fixed pitch angle on the self-starting aerodynamic characteristics of the vertical axis wind turbine are analyzed systematically. Finally, the quantification effects of the solidity and fixed pitch angle on the self-starting performance of the turbine can be obtained. The analysis in this study will provide straightforward physical insight into the self-starting aerodynamic characteristics of vertical axis wind turbine.

  6. Energy Efficient Hybrid Dual Axis Solar Tracking System

    Directory of Open Access Journals (Sweden)

    Rashid Ahammed Ferdaus

    2014-01-01

    Full Text Available This paper describes the design and implementation of an energy efficient solar tracking system from a normal mechanical single axis to a hybrid dual axis. For optimizing the solar tracking mechanism electromechanical systems were evolved through implementation of different evolutional algorithms and methodologies. To present the tracker, a hybrid dual-axis solar tracking system is designed, built, and tested based on both the solar map and light sensor based continuous tracking mechanism. These light sensors also compare the darkness and cloudy and sunny conditions assisting daily tracking. The designed tracker can track sun’s apparent position at different months and seasons; thereby the electrical controlling device requires a real time clock device for guiding the tracking system in seeking solar position for the seasonal motion. So the combination of both of these tracking mechanisms made the designed tracker a hybrid one. The power gain and system power consumption are compared with a static and continuous dual axis solar tracking system. It is found that power gain of hybrid dual axis solar tracking system is almost equal to continuous dual axis solar tracking system, whereas the power saved in system operation by the hybrid tracker is 44.44% compared to the continuous tracking system.

  7. Childhood Head and Neck Irradiation

    Science.gov (United States)

    ... Thyroid Association ® www.thyroid.org Childhood Head & Neck Irradiation What is the thyroid gland? The thyroid gland ... Thyroid Association ® www.thyroid.org Childhood Head & Neck Irradiation Thyroid nodules (see Thyroid Nodule brochure) • Thyroid nodules ...

  8. Food irradiation and consumer values

    International Nuclear Information System (INIS)

    Bruhn, C.M.; Schutz, H.G.; Sommer, R.

    1988-01-01

    A mail survey technique was used to determine if value hierarchy, locus of control, innovativeness, and demographic parameters could distinguish between subjects expressing different levels of concern and willingness to buy irradiated food. Concern toward irradiated food was lower than concern for other food safety issues, probably because many expressed uncertainty regarding irradiation. Those ranking the value “an ecologically balanced world” expressed the greatest irradiation concern. Factors which could predict high irradiation concern were being highly concerned about the use of chemical sprays on food, completing more formal education and being female; those believing that life was controlled by luck were less concerned. Irradiation concern was a principal factor determining willingness to buy irradiated foods. Innovative consumers were more likely to try irradiated foods than noninnovative. Implications for consumer education are presented

  9. Irradiation procedures and radiation dosimetry

    International Nuclear Information System (INIS)

    Izard, M.E.

    1985-01-01

    The design and construction of an irradiation facility and the process controls to monitor safety and performance are discussed. Dose rate distribution in an irradiator, dose distribution within the product and the measurement of radiation dose are outlined

  10. Profitability of irradiation plants

    International Nuclear Information System (INIS)

    Bustos R, M.E.; Gonzalez F, C.; Liceaga C, G.; Ortiz A, G.

    1997-01-01

    In any industrial process it is seek an attractive profit from the contractor and the social points of view. The use of the irradiation technology in foods allows keep their hygienically, which aid to food supply without risks for health, an increment of new markets and a losses reduction. In other products -cosmetics or disposable for medical use- which are sterilized by irradiation, this process allows their secure use by the consumers. The investment cost of an irradiation plant depends mainly of the plant size and the radioactive material reload that principally is Cobalt 60, these two parameters are in function of the type of products for irradiation and the selected doses. In this work it is presented the economic calculus and the financial costs for different products and capacities of plants. In general terms is determined an adequate utility that indicates that this process is profitable. According to the economic and commercial conditions in the country were considered two types of credits for the financing of this projects. One utilizing International credit resources and other with national sources. (Author)

  11. NSUF Irradiated Materials Library

    Energy Technology Data Exchange (ETDEWEB)

    Cole, James Irvin [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-09-01

    The Nuclear Science User Facilities has been in the process of establishing an innovative Irradiated Materials Library concept for maximizing the value of previous and on-going materials and nuclear fuels irradiation test campaigns, including utilization of real-world components retrieved from current and decommissioned reactors. When the ATR national scientific user facility was established in 2007 one of the goals of the program was to establish a library of irradiated samples for users to access and conduct research through competitively reviewed proposal process. As part of the initial effort, staff at the user facility identified legacy materials from previous programs that are still being stored in laboratories and hot-cell facilities at the INL. In addition other materials of interest were identified that are being stored outside the INL that the current owners have volunteered to enter into the library. Finally, over the course of the last several years, the ATR NSUF has irradiated more than 3500 specimens as part of NSUF competitively awarded research projects. The Logistics of managing this large inventory of highly radioactive poses unique challenges. This document will describe materials in the library, outline the policy for accessing these materials and put forth a strategy for making new additions to the library as well as establishing guidelines for minimum pedigree needed to be included in the library to limit the amount of material stored indefinitely without identified value.

  12. Wholesomeness of irradiated food

    Energy Technology Data Exchange (ETDEWEB)

    Raica, Nicholas; McDowell, Marion E.; Darby, William J.

    1963-01-15

    The wholesomeness of irradiated foods was evaluated in mice, rats, dogs, and monkeys over a 2-year period, or 4 generations. Data are presented on the effects of a diet containing radiation-processed foods on growth, reproduction, hematology, histopathology, carcinogenicity, and life span. (86 references) (C.H.)

  13. Irradiated uranium reprocessing

    International Nuclear Information System (INIS)

    Gal, I.

    1961-12-01

    Task concerned with reprocessing of irradiated uranium covered the following activities: implementing the method and constructing the cell for uranium dissolving; implementing the procedure for extraction of uranium, plutonium and fission products from radioactive uranium solutions; studying the possibilities for using inorganic ion exchangers and adsorbers for separation of U, Pu and fission products

  14. Neutrons from Antiproton Irradiation

    DEFF Research Database (Denmark)

    Bassler, Niels; Holzscheiter, Michael; Petersen, Jørgen B.B.

    the volume targeted for irradiation. A major part of this peripheral dose arise from neutrons, which in particular are problematic due to their high RBE for secondary cancer incidence. We have measured the fast and thermal neutron spectrum in different geometrical configurations in order to experimentally...

  15. CERN IRRADIATION FACILITIES.

    Science.gov (United States)

    Pozzi, Fabio; Garcia Alia, Ruben; Brugger, Markus; Carbonez, Pierre; Danzeca, Salvatore; Gkotse, Blerina; Richard Jaekel, Martin; Ravotti, Federico; Silari, Marco; Tali, Maris

    2017-09-28

    CERN provides unique irradiation facilities for applications in dosimetry, metrology, intercomparison of radiation protection devices, benchmark of Monte Carlo codes and radiation damage studies to electronics. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. Irradiated fuel bundle counter

    International Nuclear Information System (INIS)

    Campbell, J.W.; Todd, J.L.

    1975-01-01

    The design of a prototype safeguards instrument for determining the number of irradiated fuel assemblies leaving an on-power refueled reactor is described. Design details include radiation detection techniques, data processing and display, unattended operation capabilities and data security methods. Development and operating history of the bundle counter is reported. (U.S.)

  17. Centurion -- a revolutionary irradiator

    International Nuclear Information System (INIS)

    McKinney, Dan; Perrins, Robert

    2000-01-01

    The facility characteristics for irradiation of red meat and poultry differ significantly from those of medical disposables. This paper presents the results of the market requirement definition which resulted in an innovative conceptual design. The process and the 'state of the art tools' used to bring this abstract idea into a proof of concept are presented. (author)

  18. Longevity of irradiated burros

    International Nuclear Information System (INIS)

    Lushbaugh, C.C.; Brown, D.G.; Frome, E.L.

    1984-01-01

    The unique radioresistance of burros has resulted in a large-animal life-span study that began in 1951. During the course of radiation exposures, some animals at three low exposures to gamma photons survived (10, 10, and 9 exposed to 320, 425, and 545 R, respectively). In 1953, 20 burros exposed to 375 R (gamma) in 25-R/wk increments were added to this life-span study. In 1957, 33 burros exposed to mixed neutron-gamma radiation from nuclear weapons were added. Six burros exposed to 180 rads of neutron and gamma radiation (4:1) in a ''Godiva-type'' reactor were added in 1959 along with 22 controls. In the first 4 years after the single gamma exposures (320-545 R), there were deaths from pancytopenia and thrombocytopenia). Afterward, however, all deaths have been attributable to common equine diseases; none from malignancies. Today, 20 of the original 112 burros in these studies survive (13 irradiated and 7 controls). Survival curves determined for unirradiated and neutron-gamma and gamma-only irradiated burros show significant differences. Median survival time: controls, 28 yrs; gamma irradiation, 26 yrs; neutron-gamma irradiation, 23 yrs. A Weibull probability analysis predicts maximum life-span to be 42 yrs

  19. Update on meat irradiation

    International Nuclear Information System (INIS)

    Olson, D.G.

    1997-01-01

    The irradiation of meat and poultry in the United States is intended to eliminate pathogenic bacteria from raw product, preferably after packaging to prevent recontamination. Irradiation will also increase the shelf life of raw meat and poultry products approximately two to three times the normal shelf life. Current clearances in the United States are for poultry (fresh or frozen) at doses from 1.5 to 3.0 kGy and for fresh pork at doses from 0.3 to 1.0 kGy. A petition for the clearance of all red meat was submitted to the Food and Drug Administration (FDA) in July 1994. The petition is for clearances of fresh meat at doses from 1.5 to 4.5 kGy and for frozen meat at ∼2.5 to 7.5 kGy. Clearance for red meat is expected before the end of 1997. There are 28 countries that have food irradiation clearances, of which 18 countries have clearances for meat or poultry. However, there are no uniform categories or approved doses for meat and poultry among the countries that could hamper international trade of irradiated meat and poultry

  20. Involvement of p38-βTrCP-Tristetraprolin-TNFα axis in radiation pneumonitis.

    Science.gov (United States)

    Krishnamurthy, Pranathi Meda; Shukla, Shirish; Ray, Paramita; Mehra, Rohit; Nyati, Mukesh K; Lawrence, Theodore S; Ray, Dipankar

    2017-07-18

    Early release of tumor necrosis factor-alpha (TNF-α) during radiotherapy of thoracic cancers plays an important role in radiation pneumonitis, whose inhibition may provide lung radioprotection. We previously reported radiation inactivates Tristetraprolin (TTP), a negative regulator of TNF-α synthesis, which correlated with increased TNF-α release. However, the molecular events involved in radiation-induced TTP inactivation remain unclear. To determine if eliminating Ttp in mice resulted in a phenotypic response to radiation, Ttp-null mice lungs were exposed to a single dose of 15 Gy, and TNF-α release and lung inflammation were analyzed at different time points post-irradiation. Ttp-/- mice with elevated (9.5±0.6 fold) basal TNF-α showed further increase (12.2±0.9 fold, pacute lung inflammation within a week post-irradiation. Further studies using mouse lung macrophage (MH-S), human lung fibroblast (MRC-5), and exogenous human TTP overexpressing U2OS and HEK293 cells upon irradiation (a single dose of 4 Gy) promoted p38-mediated TTP phosphorylation at the serine 186 position, which primed it to be recognized by an ubiquitin ligase (E3), beta transducing repeat containing protein (β-TrCP), to promote polyubiquitination-mediated proteasomal degradation. Consequently, a serine 186 to alanine (SA) mutant of TTP was resistant to radiation-induced degradation. Similarly, either a p38 kinase inhibitor (SB203580), or siRNA-mediated β-TrCP knockdown, or overexpression of dominant negative Cullin1 mutants protected TTP from radiation-induced degradation. Consequently, SB203580 pretreatment blocked radiation-induced TNF-α release and radioprotected macrophages. Together, these data establish the involvement of the p38-βTrCP-TTP-TNFα signaling axis in radiation-induced lung inflammation and identified p38 inhibition as a possible lung radioprotection strategy.

  1. Process for irradiation of polyethylene

    International Nuclear Information System (INIS)

    White, George.

    1983-01-01

    Irradiation of polyethylene affects its processabiltiy in the fabrication of products and affects the properties of products already fabricated. The present invention relates to a process for the irradiation of polyethylene, and especially to a process for the irradiation of homopolymers of ethylene and copolymers of ethylene and higher α-olefins, in the form of granules, with low levels of electron or gamma irradiation in the presence of an atomsphere of steam

  2. Switching the uniaxial magnetic anisotropy by ion irradiation induced compensation

    Science.gov (United States)

    Yuan, Ye; Amarouche, Teyri; Xu, Chi; Rushforth, Andrew; Böttger, Roman; Edmonds, Kevin; Campion, Richard; Gallagher, Bryan; Helm, Manfred; Jürgen von Bardeleben, Hans; Zhou, Shengqiang

    2018-04-01

    In the present work, the uniaxial magnetic anisotropy of GaMnAsP is modified by helium ion irradiation. According to the micro-magnetic parameters, e.g. resonance fields and anisotropy constants deduced from ferromagnetic resonance measurements, a rotation of the magnetic easy axis from out-of-plane [0 0 1] to in-plane [1 0 0] direction is achieved. From the application point of view, our work presents a novel avenue in modifying the uniaxial magnetic anisotropy in GaMnAsP with the possibility of lateral patterning by using lithography or focused ion beam.

  3. Food irradiation technology

    International Nuclear Information System (INIS)

    Cetinkaya, N.

    1999-01-01

    Trade in food and agricultural products is important to all countries, the economies of many developing countries would be significantly improved if they were able to export more food and agricultural products. Unfortunately, many products can not be traded because they are infested with, or hosts to, harmful pests, contaminated with microorganisms, or spoil quickly. Foods contaminated with microorganisms cause economic losses, widespread illness and death. Several technologies and products have been developed to resolve problems in trading food and to improve food safety, but none can provide all the solutions. Irradiation is an effective technology to resolve technical problems in trade of many food and agricultural products, either as a stand- alone technology or in combination with others. As a disinfestation treatment it allows different levels of quarantine security to be targeted and it is one of few methods to control internal pests. The ability of irradiation virtually to eliminate key pathogenic organisms from meat, poultry, and spices is an important public health advantage. In addition to controlling pests and eliminating harmful bacteria, irradiation also extends the storage life of many foods. In the laboratories of Turkish Atomic Energy Authority, many research projects were completed on the effects of gamma irradiation to the storage life of chicken meat, anchovy, Turkish fermented sausage, dried and fresh fruits and vegetables and also research projects were conducted on the effects of gamma irradiation on microorganisms (Salmonella, Campylo-bacteria, E.coli and S.aureus in white and red meat) and parasites (food-borne, trichostrongylus spp. and Nematodes spp.)

  4. Improvement of irradiation effects database

    International Nuclear Information System (INIS)

    Yuan Guohuo; Xu Xi; Jia Wenhai

    2003-01-01

    The design method of irradiation effects database is related in this paper. The structure of irradiation effects database is perfected by Delphi, query and calculation of the data have completed, and printing and outputting data report form have fulfilled. Therefore, data storage platform for reliability and vulnerability analyzing of harden irradiation effects of the component and system is offered

  5. Canadian perspectives on food irradiation

    International Nuclear Information System (INIS)

    Kunstadt, P.

    1988-01-01

    Canada has been in the forefront of irradiation technology for some 30 years. Nearly 90 of the 140 irradiators used worldwide are Canadian-built, yet Canadian food processors have been very slow to use the technology. The food irradiation regulatory situation in Canada, the factors that influence it, and some significant non-regulatory developments are reviewed. (author)

  6. New Irradiation Method with Indocyanine Green-Loaded Nanospheres for Inactivating Periodontal Pathogens.

    Science.gov (United States)

    Sasaki, Yasuyuki; Hayashi, Jun-Ichiro; Fujimura, Takeki; Iwamura, Yuki; Yamamoto, Genta; Nishida, Eisaku; Ohno, Tasuku; Okada, Kosuke; Yamamoto, Hiromitsu; Kikuchi, Takeshi; Mitani, Akio; Fukuda, Mitsuo

    2017-01-13

    Antimicrobial photodynamic therapy (aPDT) has been proposed as an adjunctive strategy for periodontitis treatments. However, use of aPDT for periodontal treatment is complicated by the difficulty in accessing morphologically complex lesions such as furcation involvement, which the irradiation beam (which is targeted parallel to the tooth axis into the periodontal pocket) cannot access directly. The aim of this study was to validate a modified aPDT method that photosensitizes indocyanine green-loaded nanospheres through the gingivae from outside the pocket using a diode laser. To establish this trans-gingival irradiation method, we built an in vitro aPDT model using a substitution for gingivae. Irradiation conditions and the cooling method were optimized before the bactericidal effects on Porphyromonas gingivalis were investigated. The permeable energy through the gingival model at irradiation conditions of 2 W output power in a 50% duty cycle was comparable with the transmitted energy of conventional irradiation. Intermittent irradiation with air cooling limited the temperature increase in the gingival model to 2.75 °C. The aPDT group showed significant bactericidal effects, with reductions in colony-forming units of 99.99% after 5 min of irradiation. This effect of aPDT against a periodontal pathogen demonstrates the validity of trans-gingival irradiation for periodontal treatment.

  7. New Irradiation Method with Indocyanine Green-Loaded Nanospheres for Inactivating Periodontal Pathogens

    Directory of Open Access Journals (Sweden)

    Yasuyuki Sasaki

    2017-01-01

    Full Text Available Antimicrobial photodynamic therapy (aPDT has been proposed as an adjunctive strategy for periodontitis treatments. However, use of aPDT for periodontal treatment is complicated by the difficulty in accessing morphologically complex lesions such as furcation involvement, which the irradiation beam (which is targeted parallel to the tooth axis into the periodontal pocket cannot access directly. The aim of this study was to validate a modified aPDT method that photosensitizes indocyanine green-loaded nanospheres through the gingivae from outside the pocket using a diode laser. To establish this trans-gingival irradiation method, we built an in vitro aPDT model using a substitution for gingivae. Irradiation conditions and the cooling method were optimized before the bactericidal effects on Porphyromonas gingivalis were investigated. The permeable energy through the gingival model at irradiation conditions of 2 W output power in a 50% duty cycle was comparable with the transmitted energy of conventional irradiation. Intermittent irradiation with air cooling limited the temperature increase in the gingival model to 2.75 °C. The aPDT group showed significant bactericidal effects, with reductions in colony-forming units of 99.99% after 5 min of irradiation. This effect of aPDT against a periodontal pathogen demonstrates the validity of trans-gingival irradiation for periodontal treatment.

  8. UV irradiation assisted growth of ZnO nanowires on optical fiber surface

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Bo; Shi, Tielin; Liao, Guanglan; Li, Xiaoping; Huang, Jie; Zhou, Temgyuan; Tang, Zirong, E-mail: zirong@mail.hust.edu.cn

    2017-06-01

    Highlights: • A new fabrication process combined a hydrothermal process with UV irradiation from optical fiber is developed. • The growth of ZnO nanowires is efficient in the utilization of UV light. • A novel hybrid structure which integrates ZnO nanowires on optical fiber surface is synthesized. • The UV assisted growth of ZnO nanowires shows preferred orientation and better quality. • A mechanism of growing ZnO nanowires under UV irradiation is proposed. - Abstract: In this paper, a novel approach was developed for the enhanced growth of ZnO nanowires on optical fiber surface. The method combined a hydrothermal process with the efficient UV irradiation from the fiber core, and the effects of UV irradiation on the growth behavior of ZnO nanowires were investigated. The results show that UV irradiation had great effects on the preferred growth orientation and the quality of the ZnO nanowires. The crystallization velocity along the c-axis would increase rapidly with the increase of the irradiation power, while the growth process in the lateral direction was marginally affected by the irradiation. The structure of ZnO nanowires also shows less oxygen vacancy with UV irradiation of higher power. The developed approach is applicable for the efficient growth of nanowires on the fiber surface, and the ZnO nanowires/optical fiber hybrid structures have great potentials for a wide variety of applications such as optical fiber sensors and probes.

  9. Design Of Single-Axis And Dual-Axis Solar Tracking Systems Protected Against High Wind Speeds

    Directory of Open Access Journals (Sweden)

    Mai Salaheldin Elsherbiny

    2017-09-01

    Full Text Available Solar energy is rapidly gaining ground as an important mean of expanding renewable energy use. Solar tracking is employed in order to maximize collected solar radiation by a photovoltaic panel. In this paper we present a prototype for Automatic solar tracker that is designed using Arduino UNO with Wind sensor to Cease Wind effect on panels if wind speed exceeds certain threshold. The Proposed solar tracker tracks the location of the sun anywhere in any time by calculating the position of the sun. For producing the maximum amount of solar energy a solar panel must always be perpendicular to the source of light. Because the sun motion plane varies daily and during the day it moves from east to west one needs two axis tracking to follow the suns position. Maximum possible power is collected when two axis tracking is done. However two axis tracking is relatively costly and complex. A compromise between maximum power collection and system simplicity is obtained by single axis tracking where the plane North south axis is fixed while the east west motion is accomplished. This work deals with the design of both single and two axis tracking systems. Automatic trackers is also compared to Fixed one in terms of Energy generated Efficiency Cost and System reliability.

  10. Ultrasound-guided internal jugular vein access: Comparison between short axis and long axis techniques

    Directory of Open Access Journals (Sweden)

    Tarek F Tammam

    2013-01-01

    Full Text Available The use of real-time ultrasound (US is advantageous in the insertion of central venous catheters (CVCs in adults, especially in whom difficulties are anticipated for various reasons. The aim of the present study was to compare two different real-time 2-dimensional US-guided techniques [short axis view/out-of-plane approach (SAX OOP approach versus long axis view/in-plane approach (LAX IP approach] for internal jugular vein (IJV cannulation. In this prospective study, 90 critical care and hemodialysis patients were assigned for insertion of CVCs using either the real-time US-guided (SAX OOP approach or LAX IP approach or landmark technique (control group. Failed catheter placement, risk of complications from placement, failure on first attempt at placement, number of attempts until successful catheterization, time to successful catheterization, incidence of central line-associated blood stream infection (CLA-BSI and demographics of each patient were recorded. There were no significant differences in patient′s demographic characteristics, side of cannulation (right or left or presence of risk factors for difficult venous cannulation between the three groups of patients. Cannulation of the IJV was achieved in all patients by using US (SAX OOP and LAX IP approaches and in 27 of the patients (90% by using the landmark technique (P = 0.045. Average access time (skin to vein and number of attempts were comparable between the SAX OOP and the LAX IP approaches while significantly reduced in both US groups of patients compared with the landmark group (P <0.001. In the landmark group, puncture of the carotid artery occurred in 16.7% of the patients, hematoma in 23.3% of the patients, pneumothorax in 3.3% of the patients and CLA-BSI in 20% of the patients, which were all significantly increased compared with the US group (P <0.05. The findings of this study suggest that the SAX OOP and LAX IP approaches were comparable for cannulation of IJV in critical

  11. Irradiation of Anastrepha suspensa (Diptera: Tephritidae): new irradiation facility

    International Nuclear Information System (INIS)

    Smittle, B.J.

    1993-01-01

    An irradiation facility financed by a Cooperative Agreement with the U.S. Dept. of Energy, is near completion in Gainesville, FL. It utilizes a GE-CGR linear accelerator as the irradiation source in a two level design. The lower level has a one meter horn for 10 Me V electrons to irradiate shallow layers of commodities. The upper level has a 2.5 meter horn equipped to produce 5 Me V X-rays to irradiate loads up to pallet size. Automated conveyors transport materials to be irradiated. The facility is divided for irradiated and unirradiated commodities with freezer and refrigerated storage on both sides. The facility is designed for both research and demonstration purposes and has the capacity to irradiate over 10 million Caribbean fruit fly larvae or pupae per minute

  12. Post irradiation test report of irradiated DUPIC simulated fuel

    International Nuclear Information System (INIS)

    Yang, Myung Seung; Jung, I. H.; Moon, J. S. and others

    2001-12-01

    The post-irradiation examination of irradiated DUPIC (Direct Use of Spent PWR Fuel in CANDU Reactors) simulated fuel in HANARO was performed at IMEF (Irradiated Material Examination Facility) in KAERI during 6 months from October 1999 to March 2000. The objectives of this post-irradiation test are i) the integrity of the capsule to be used for DUPIC fuel, ii) ensuring the irradiation requirements of DUPIC fuel at HANARO, iii) performance verification in-core behavior at HANARO of DUPIC simulated fuel, iv) establishing and improvement the data base for DUPIC fuel performance verification codes, and v) establishing the irradiation procedure in HANARO for DUPIC fuel. The post-irradiation examination performed are γ-scanning, profilometry, density, hardness, observation the microstructure and fission product distribution by optical microscope and electron probe microanalyser (EPMA)

  13. Postnatal development of the atlas and axis: CT study

    International Nuclear Information System (INIS)

    Byun, Sung Su; Kim, Hyung Jin; Lim, Myung Kwan; Kim, Won Hong; Jeon, Yong Sun; Kim, Jeong Ho; Kim, Sung Tae

    2003-01-01

    To evaluate normal postnatal development of the atlas and axis by means of CT scanning. We prospectively analyzed CT scans of the developing atlas and axis of 200 normal children aged less than 14, investigating the CT appearance of these regions with particular attenuation to two synchondroses related to the atlas and four synchondroses and one ossification center related to the axis. Fusion varying was categorized as either low (grade1-5) or high (grade4-5), according to the varying degrees of fusion at each synchondrosis of ossification center. Neurocentral synchondrosis of the atlas was low grade in all children less than five, and high grade in all aged nine or more, while posterior synchondrosis of the atlas was low grade in 97% of children less than three and high grade in 99% aged three or more. As for the axis, neurocentral synchondrosis was low grade in all children less than three, and high grade in 97% of children aged five or more. PS of the axis was low grade in both children less than 6 months, and high grade in all aged two years or more. Dentocentral synchondrosis of the axis was low grade in 93% of children less than three and high grade in 96% of those aged at least five. Intradental axial synchondrosis was high grade in all children. Fusion of the terminal ossicle with the remainder of the dens was low in all children less than five and high in 97% of those aged nine of more. CT can help determine the parameters of normal postnatal development of the atlas and axis. A knowledge of normal ossification patterns of these regions may help provide an understanding of developmental anomalies and also help prevent confusion with fractures

  14. The anatomical tibial axis: reliable rotational orientation in knee replacement.

    Science.gov (United States)

    Cobb, J P; Dixon, H; Dandachli, W; Iranpour, F

    2008-08-01

    The rotational alignment of the tibia is an unresolved issue in knee replacement. A poor functional outcome may be due to malrotation of the tibial component. Our aim was to find a reliable method for positioning the tibial component in knee replacement. CT scans of 19 knees were reconstructed in three dimensions and orientated vertically. An axial plane was identified 20 mm below the tibial spines. The centre of each tibial condyle was calculated from ten points taken round the condylar cortex. The tibial tubercle centre was also generated as the centre of the circle which best fitted eight points on the outside of the tubercle in an axial plane at the level of its most prominent point. The derived points were identified by three observers with errors of 0.6 mm to 1 mm. The medial and lateral tibial centres were constant features (radius 24 mm (SD 3), and 22 mm (SD 3), respectively). An anatomical axis was created perpendicular to the line joining these two points. The tubercle centre was found to be 20 mm (SD 7) lateral to the centre of the medial tibial condyle. Compared with this axis, an axis perpendicular to the posterior condylar axis was internally rotated by 6 degrees (SD 3). An axis based on the tibial tubercle and the tibial spines was also internally rotated by 5 degrees (sd 10). Alignment of the knee when based on this anatomical axis was more reliable than either the posterior surfaces or any axis involving the tubercle which was the least reliable landmark in the region.

  15. Mechanical impedance of the sitting human body in single-axis compared to multi-axis whole-body vibration exposure.

    Science.gov (United States)

    Holmlund, P; Lundström, R

    2001-01-01

    The study was aimed to investigate the mechanical impedance of the sitting human body and to compare data obtained in laboratory single-axis investigations with multi-axis data from in vehicle measurements. The experiments were performed in a laboratory for single-axis measurements. The multi-axis exposure was generated with an eight-seat minibus where the rear seats had been replaced with a rigid one. The subjects in the multi-axis experiment all participated in the single-axis experiments. There are quite a few investigations in the literature describing the human response to single-axis exposure. The response from the human body can be expected to be affected by multi-axis input in a different way than from a single-axis exposure. The present knowledge of the effect of multiple axis exposure is very limited. The measurements were performed using a specially designed force and accelerometer plate. This plate was placed between the subject and the hard seat. Outcome shows a clear difference between mechanical impedance for multi-axis exposure compared to single-axis. This is especially clear in the x-direction where the difference is very large. The conclusion is that it seems unlikely that single-axis mechanical impedance data can be directly transferred to a multi-axis environment. This is due to the force cross-talk between different directions.

  16. The return of food irradiation

    International Nuclear Information System (INIS)

    Hammerton, K.

    1992-01-01

    In discussing the need for food irradiation the author examines the problems that arise in processing foods of different kinds: spices, meat, fruits and vegetables. It is demonstrated that the relatively low dose of radiation required to eliminate the reproductive capacity of the pest can be tolerated by most fruits and vegetables without damage. Moreover the safety of irradiated food is acknowledged by major national and international food organizations and committees. The author agreed that when food irradiation has been approved by a country, consumers should be able to choose between irradiated and non-irradiated food. To enable the choice, clear and unambiguous labelling must be enforced. 13 refs., 1 tab., ills

  17. Diamond Machining of an Off-Axis Biconic Aspherical Mirror

    Science.gov (United States)

    Ohl, Raymond G.; Preuss, Werner; Sohn, Alex; MacKenty, John

    2009-01-01

    Two diamond-machining methods have been developed as part of an effort to design and fabricate an off-axis, biconic ellipsoidal, concave aluminum mirror for an infrared spectrometer at the Kitt Peak National Observatory. Beyond this initial application, the methods can be expected to enable satisfaction of requirements for future instrument mirrors having increasingly complex (including asymmetrical), precise shapes that, heretofore, could not readily be fabricated by diamond machining or, in some cases, could not be fabricated at all. In the initial application, the mirror is prescribed, in terms of Cartesian coordinates x and y, by aperture dimensions of 94 by 76 mm, placements of -2 mm off axis in x and 227 mm off axis in y, an x radius of curvature of 377 mm, a y radius of curvature of 407 mm, an x conic constant of 0.078, and a y conic constant of 0.127. The aspect ratio of the mirror blank is about 6. One common, "diamond machining" process uses single-point diamond turning (SPDT). However, it is impossible to generate the required off-axis, biconic ellipsoidal shape by conventional SPDT because (1) rotational symmetry is an essential element of conventional SPDT and (2) the present off-axis biconic mirror shape lacks rotational symmetry. Following conventional practice, it would be necessary to make this mirror from a glass blank by computer-controlled polishing, which costs more than diamond machining and yields a mirror that is more difficult to mount to a metal bench. One of the two present diamond machining methods involves the use of an SPDT machine equipped with a fast tool servo (FTS). The SPDT machine is programmed to follow the rotationally symmetric asphere that best fits the desired off-axis, biconic ellipsoidal surface. The FTS is actuated in synchronism with the rotation of the SPDT machine to generate the difference between the desired surface and the best-fit rotationally symmetric asphere. In order to minimize the required stroke of the FTS

  18. Measurement Axis Searching Model for Terrestrial Laser Scans Registration

    Directory of Open Access Journals (Sweden)

    Shaoxing Hu

    2016-01-01

    Full Text Available Nowadays, terrestrial Lidar scans can cover rather a large area; the point densities are strongly varied because of the line-of-sight measurement principle in potential overlaps with scans taken from different viewpoints. Most of the traditional methods focus on registration algorithm and ignore searching model. Sometimes the traditional methods are directly used to align two point clouds; a large critically unsolved problem of the large biases will be created in areas distant from the overlaps while the local overlaps are often aligned well. So a novel measurement axis searching model (MASM has been proposed in this paper. The method includes four steps: (1 the principal axis fitting, (2 the measurement axis generation, (3 low-high-precision search, and (4 result generation. The principal axis gives an orientation to the point cloud; the search scope is limited by the measurement axis. The point cloud orientation can be adjusted gradually until the achievement of the global optimum using low- and high-precision search. We perform some experiments with simulated point clouds and real terrestrial laser scans. The results of simulated point clouds have shown the processing steps of our method, and the results of real terrestrial laser scans have shown the sensitivity of the approach with respect to the indoor and outdoor scenes.

  19. Vitamin A in irradiated foodstuffs

    International Nuclear Information System (INIS)

    Diehl, J.F.

    1979-01-01

    Vitamin A losses induced by 10 MeV electrons in cream cheese, calf liver sausage, pig liver, whole egg powder and margarine continued to increase during storage for 4-8 weeks in presence of air. Thus, vitamin A loss in sausage irradiated with 5 Mrad was 22% on the day after irradiation, 61% after 4 weeks. Irradiation and storage at 0 0 C instead of at ambient temperature reduced these losses considerably. Exclusion of air (vacuum, nitrogen) or irradiation on dry ice (approx. -80 0 C) were even more effective in preventing destruction of vitamin A. After 4 weeks of storage, cream cheese irradiated at 5 Mrad had lost 60% when irradiated and stored in air at ambient temperature, 20% in nitrogen atmosphere, 5% in vacuum package, and 5% when irradiated on dry ice and stored at ambient temperture. (orig.) [de

  20. Vitamin A in irradiated foodstuffs

    International Nuclear Information System (INIS)

    Diehl, J.F.

    1979-01-01

    Vitamin A losses induced by 10 MeV electrons in cream cheese, calf liver sausage, pig liver, whole egg powder and magarine continued to increase during storage for 4-8 weeks in presence of air. Thus, vitamin A loss in sausage irradiated with 5 Mrad was 22% on the day after irradiation, 61% after 4 weeks. Irradiation and storage at 0 0 C instead of ambient temperature reduced these losses considerably. Exclusion of air (vacuum, nitrogen) or irradiation on dry ice (approx. -80 0 C) were even more effective in preventing destruction of vitamin A. After 4 weeks of storage, cream cheese irradiated at 5 Mrad had lost 60% when irradiated and stored in air at ambient temperature, 20% in nitrogen atmosphere, 5% in vacuum package, and 5% when irradiated on dry ice and stored at ambient temperature. (orig.) [de

  1. Irradiation of foods

    International Nuclear Information System (INIS)

    Pai, J.S.

    2001-01-01

    Although irradiation is being investigated for the last more than 50 years for the application in preservation of food, it has not yet been exploited commercially in some countries like India. No other food processing technique has undergone such close scrutiny. There are many advantages to this process, which few others can claim. The temperature remains ambient during the process and the form of the food does not change resulting in very few changes in the sensory and nutritive quality of the food product. At the same time the microorganisms are effectively destroyed. Most of the spoilage and pathogenic organisms are sensitive to irradiation. Fortunately, most governments are supportive for the process and enacting laws permitting the process for foods

  2. The irradiation of foods

    International Nuclear Information System (INIS)

    Laizier, J.; Thomas, J.C.; Nairaud, D.

    1998-01-01

    The irradiation of foods opens the way to new products and processes that are potentially very attractive to the agro-food industry. The treatments have been shown to be safe and their implementation can be adequately controlled. However, to date, these methods have only been used in a very restricted way. We discuss here the reasons for this limited use, the factors likely to affect future development of the technique and its current regulation. The next publication of European Community directives should greatly change the nature of French regulation. In particular, there are likely to be major changes in product labelling, with an obligation not only to label treated products but also to label ingredients and ingredients of constituents of the product as being 'treated by irradiation' or 'treated with ionising radiation'. (authors)

  3. Food Irradiation. Standing legislation

    International Nuclear Information System (INIS)

    Verdejo S, M.

    1997-01-01

    The standing legislation in Mexico on food irradiation matter has its basis on the Constitutional Policy of the Mexican United States on the 4 Th. article by its refers to Secretary of Health, 27 Th. article to the Secretary of Energy and 123 Th. of the Secretary of Work and Social Security. The laws and regulations emanated of the proper Constitution establishing the general features which gives the normative frame to this activity. The general regulations of Radiological Safety expedited by the National Commission for Nuclear Safety and Safeguards to state the specifications which must be fulfill the industrial installations which utilizing ionizing radiations, between this line is founded, just as the requirements for the responsible of the radiological protection and the operation of these establishments. The project of Regulation of the General Health Law in matter of Sanitary Control of Benefits and Services, that in short time will be officialized, include a specific chapter on food irradiation which considers the International Organizations Recommendations and the pertaining harmonization stated for Latin America, which elaboration was in charge of specialized group where Mexico was participant. Additionally, the Secretary of Health has a Mexican Official Standard NOM-033-SSA1-1993 named 'Food irradiation; permissible doses in foods, raw materials and support additives' standing from the year 1995, where is established the associated requirements to the control registers, service constancies and dose limits for different groups of foods, moreover of the specific guidelines for its process. This standard will be adequate considering the updating Regulation of Benefits and Services and the limits established the Regulation for Latin America. The associated laws that cover in general terms it would be the requirements for food irradiation although such term is not manageable. (Author)

  4. Surface segregation during irradiation

    International Nuclear Information System (INIS)

    Rehn, L.E.; Lam, N.Q.

    1985-10-01

    Gibbsian adsorption is known to alter the surface composition of many alloys. During irradiation, four additional processes that affect the near-surface alloy composition become operative: preferential sputtering, displacement mixing, radiation-enhanced diffusion and radiation-induced segregation. Because of the mutual competition of these five processes, near-surface compositional changes in an irradiation environment can be extremely complex. Although ion-beam induced surface compositional changes were noted as long as fifty years ago, it is only during the past several years that individual mechanisms have been clearly identified. In this paper, a simple physical description of each of the processes is given, and selected examples of recent important progress are discussed. With the notable exception of preferential sputtering, it is shown that a reasonable qualitative understanding of the relative contributions from the individual processes under various irradiation conditions has been attained. However, considerably more effort will be required before a quantitative, predictive capability can be achieved. 29 refs., 8 figs

  5. Irradiation of dates

    International Nuclear Information System (INIS)

    Farkas, J.; Al-Charchafchy, F.; Al-Shaikhaly, M.H.; Mirjan, J.; Auda, H.

    1974-01-01

    Testing of the technical feasibility of radurization of fresh dates was attempted. In addition preliminary studies were carried out to investigate the applicability of gamma rays to date syrup manufacture. The varieties Zahdi, Lelwi and Tabarzel were studied at different stages of ripening. The eating quality of fresh dates was not affected significantly by irradiation even with doses of 270 and 540 krad. The duration of the softening process, after-ripening, of dates was prolonged by low doses of 10-30 krad in the majority of the experimental batches. The time period of after-ripening was reduced with 270 krad, as well as with 540 krad as a result of shortening of the induction period, i.e. the time after which the date begins to soften. The microbial spoilage of khalaal Lelwi dates was considerably reduced by irradiation with doses above 90 krad. The dibis yield of fully rutab dates was highly increased by the radiation doses of 375 to 2000 krad. The darkness and viable cell count of dibis pressed from irradiated dates were significantly lower than that of untreated dates. (F.J.)

  6. Apparatus for internal irradiation

    International Nuclear Information System (INIS)

    Hooft, E.V.

    1980-01-01

    Apparatus for internal irradiation wherein the radioactive material is applied in the shape of a ball row consisting of contiguous radioactive and neutral balls. This ball row is prepared beforehand and is pneumatically transferred to an applicator tube adapted to be introduced into a body cavity. In order that the balls may stay exactly in the right places during the irradiation, the applicator tube is provided with an internal channel having a narrow end portion, passing through a shoulder into the remaining wider portion, and a final ball is added to each ball row, this final ball having a larger diameter than the other balls, so that it is not admitted in the narrow end portion of the internal channel in the applicator tube. Thus, upon introduction of a ball row, the final ball is arrested by the shoulder and keeps the other balls in place. A plurality of applicator tubes may be applied, each of which is associated with an intermediate container in which the ball row is composed. After the irradiation, the ball row is returned through the intermediate container to a sorting device directing the balls to appropriate storage containers. However, the final ball is retained in the intermediate container, so that it may be added to the next ball row to be composed

  7. Neutron irradiation of sapphire for compressive strengthening. I. Processing conditions and compressive strength

    Energy Technology Data Exchange (ETDEWEB)

    Regan, Thomas M. E-mail: thomas_regan@uml.edu; Harris, Daniel C. E-mail: harrisdc@navair.navy.mil; Stroud, Rhonda M.; White, John R

    2002-01-01

    Sapphire suffers a dramatic loss of c-axis compression strength at elevated temperatures. Irradiation of sapphire with fission-spectrum neutrons to an exposure of {approx}10{sup 22} neutrons/m{sup 2} in the core of a 1 MW fission reactor increased the c-axis compression strength by a factor of {approx}3 at 600 deg. C. Strength was similarly improved when 99% of slow neutrons ({<=}0.1 eV) were removed by {sup 10}B and Cd shields during irradiation. Annealing at 600 deg. C for 10 min changed the yellow-brown color of irradiated sapphire to pale yellow, but had no effect on compressive strength. Annealing irradiated sapphire at 1200 deg. C for 24 h reduced the compressive strength to its baseline value. Transmission electron microscopy suggests that fast-neutron-induced displacement damage inhibits the propagation of r-plane twins which are responsible for the low compressive strength. When irradiated with {sup 10}B and Cd shielding, sapphire that was not grown in iridium crucibles is safe for unrestricted handling after 1 month.

  8. Neutron irradiation of sapphire for compressive strengthening. I. Processing conditions and compressive strength

    International Nuclear Information System (INIS)

    Regan, Thomas M.; Harris, Daniel C.; Stroud, Rhonda M.; White, John R.

    2002-01-01

    Sapphire suffers a dramatic loss of c-axis compression strength at elevated temperatures. Irradiation of sapphire with fission-spectrum neutrons to an exposure of ∼10 22 neutrons/m 2 in the core of a 1 MW fission reactor increased the c-axis compression strength by a factor of ∼3 at 600 deg. C. Strength was similarly improved when 99% of slow neutrons (≤0.1 eV) were removed by 10 B and Cd shields during irradiation. Annealing at 600 deg. C for 10 min changed the yellow-brown color of irradiated sapphire to pale yellow, but had no effect on compressive strength. Annealing irradiated sapphire at 1200 deg. C for 24 h reduced the compressive strength to its baseline value. Transmission electron microscopy suggests that fast-neutron-induced displacement damage inhibits the propagation of r-plane twins which are responsible for the low compressive strength. When irradiated with 10 B and Cd shielding, sapphire that was not grown in iridium crucibles is safe for unrestricted handling after 1 month

  9. Dual axis operation of a micromachined rate gyroscope

    Energy Technology Data Exchange (ETDEWEB)

    Juneau, T. [BSAC, Berkeley, CA (United States); Pisano, A.P. [Univ. California, Berkeley, CA (United States). Dept. of Mechanical Engineering; Smith, J. [Sandia National Lab., Albuquerque, NM (United States)

    1997-04-01

    Since micromachining technology has raised the prospect of fabricating high performance sensors without the associated high cost and large size, many researchers have investigated micromachined rate gyroscopes. The vast majority of research has focused on single input axis rate gyroscopes, but this paper presents work on a dual input axis micromachined rate gyroscope. The key to successful simultaneous dual axis operation is the quad symmetry of the circular oscillating rotor design. Untuned gyroscopes with mismatched modes yielded random walk as low as 10{degrees}/{radical}hour with cross sensitivity ranging from 6% to 16%. Mode frequency matching via electrostatic tuning allowed performance better than 2{degrees}/{radical}hour, but at the expense of excessive cross sensitivity.

  10. Spin axis offset calibration on THEMIS using mirror modes

    Directory of Open Access Journals (Sweden)

    D. Frühauff

    2017-01-01

    Full Text Available A newly developed method for determining spin axis offsets of magnetic field instruments on spacecraft is applied to THEMIS. The formerly used determination method, relying on solar wind Alfvénic fluctuations, was rarely applicable due to the orbital restrictions of the mission. With the new procedure, based on magnetic field observation of mirror modes in the magnetosheath, updated spin axis offsets can be estimated approximately once per year. Retrospective calibration of all THEMIS magnetic field measurements is thereby made possible. Since, up to this point, spin axis offsets could hardly ever be calculated due to the mission's orbits, this update represents a substantial improvement to the data. The approximate offset stability is estimated to be < 0.75 nT year−1 for the complete course of the mission.

  11. Subquadratic medial-axis approximation in $\\mathbb{R}^3$

    Directory of Open Access Journals (Sweden)

    Christian Scheffer

    2015-09-01

    Full Text Available We present an algorithm that approximates the medial axis of a smooth manifold in $\\mathbb{R}^3$ which is given by a sufficiently dense point sample. The resulting, non-discrete approximation is shown to converge to the medial axis as the sampling density approaches infinity. While all previous algorithms guaranteeing convergence have a running time quadratic in the size $n$ of the point sample, we achieve a running time of at most $\\mathcal{O}(n\\log^3 n$. While there is no subquadratic upper bound on the output complexity of previous algorithms for non-discrete medial axis approximation, the output of our algorithm is guaranteed to be of linear size.

  12. Method of making a modular off-axis solar concentrator

    Science.gov (United States)

    Plesniak, Adam P.; Hall, John C.

    2017-05-23

    A method of making a solar concentrator may include forming a receiving wall having an elongated wall, a first side wall and a second side wall; attaching the first side wall and the second side wall to a reflecting wall to form a housing having an internal volume with an opening; forming a lip on the receiving wall and the reflecting wall; attaching a cover to the receiving wall and the reflecting wall at the lip to seal the opening into the internal volume, thereby creating a rigid structure; and mounting at least one receiver having at least one photovoltaic cell on the elongated wall to receive solar radiation entering the housing and reflected by the receiving wall, the receiver having an axis parallel with a surface normal of the photovoltaic cell, such that the axis is disposed at a non-zero angle relative to the vertical axis of the opening.

  13. Role of Met Axis in Head and Neck Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yiru, E-mail: xuyiru@umich.edu; Fisher, Gary J., E-mail: xuyiru@umich.edu [Department of Dermatology, University of Michigan, Ann Arbor, MI 48109 (United States)

    2013-11-26

    Head and neck cancer is the sixth most common type of cancer worldwide. Despite advances in aggressive multidisciplinary treatments, the 5-year survival rate for this dreadful disease is only 50%, mostly due to high rate of recurrence and early involvement of regional lymph nodes and subsequent metastasis. Understanding the molecular mechanisms responsible for invasion and metastasis is one of the most pressing goals in the field of head and neck cancer. Met, also known as hepatocyte growth factor receptor (HGFR), is a member of the receptor protein tyrosine kinase (RPTK) family. There is compelling evidence that Met axis is dysregulated and plays important roles in tumorigenesis, progression, metastasis, angiogenesis, and drug resistance in head and neck cancer. We describe in this review current understanding of Met axis in head and neck cancer biology and development of therapeutic inhibitors targeting Met axis.

  14. The microbiota-gut-brain axis in functional gastrointestinal disorders.

    Science.gov (United States)

    De Palma, Giada; Collins, Stephen M; Bercik, Premysl

    2014-01-01

    Functional gastrointestinal disorders (FGIDs) are highly prevalent and pose a significant burden on health care and society, and impact patients' quality of life. FGIDs comprise a heterogeneous group of disorders, with unclear underlying pathophysiology. They are considered to result from the interaction of altered gut physiology and psychological factors via the gut-brain axis, where brain and gut symptoms are reciprocally influencing each other's expression. Intestinal microbiota, as a part of the gut-brain axis, plays a central role in FGIDs. Patients with Irritable Bowel Syndrome, a prototype of FGIDs, display altered composition of the gut microbiota compared with healthy controls and benefit, at the gastrointestinal and psychological levels, from the use of probiotics and antibiotics. This review aims to recapitulate the available literature on FGIDs and microbiota-gut-brain axis.

  15. Steroids, stress and the gut microbiome-brain axis.

    Science.gov (United States)

    Tetel, M J; de Vries, G J; Melcangi, R C; Panzica, G; O'Mahony, S M

    2018-02-01

    It is becoming well established that the gut microbiome has a profound impact on human health and disease. In this review, we explore how steroids can influence the gut microbiota and, in turn, how the gut microbiota can influence hormone levels. Within the context of the gut microbiome-brain axis, we discuss how perturbations in the gut microbiota can alter the stress axis and behaviour. In addition, human studies on the possible role of gut microbiota in depression and anxiety are examined. Finally, we present some of the challenges and important questions that need to be addressed by future research in this exciting new area at the intersection of steroids, stress, gut-brain axis and human health. © 2017 British Society for Neuroendocrinology.

  16. Off-axis and inline electron holography: Experimental comparison

    International Nuclear Information System (INIS)

    Latychevskaia, Tatiana; Formanek, Petr; Koch, C.T.; Lubk, Axel

    2010-01-01

    Electron holography is a very powerful technique for mapping static electric and magnetic potentials down to atomic resolution. While electron holography is commonly considered synonymous with its off-axis variant in the high energy electron microscopy community, inline electron holography is widely applied in low-energy electron microscopy, where the realization of the off-axis setup is still an experimental challenge. This paper demonstrates that both inline and off-axis holography may be used to recover amplitude and phase shift of the very same object, in our example latex spheres of 90 and 200 nm in diameter, producing very similar results, provided the object does not charge under the electron beam.

  17. The structure of genetic and environmental risk factors for syndromal and subsyndromal common DSM-IV axis I and all axis II disorders.

    Science.gov (United States)

    Kendler, Kenneth S; Aggen, Steven H; Knudsen, Gun Peggy; Røysamb, Espen; Neale, Michael C; Reichborn-Kjennerud, Ted

    2011-01-01

    The authors sought to clarify the structure of the genetic and environmental risk factors for 22 DSM-IV disorders: 12 common axis I disorders and all 10 axis II disorders. The authors examined syndromal and subsyndromal axis I diagnoses and five categories reflecting number of endorsed criteria for axis II disorders in 2,111 personally interviewed young adult members of the Norwegian Institute of Public Health Twin Panel. Four correlated genetic factors were identified: axis I internalizing, axis II internalizing, axis I externalizing, and axis II externalizing. Factors 1 and 2 and factors 3 and 4 were moderately correlated, supporting the importance of the internalizing-externalizing distinction. Five disorders had substantial loadings on two factors: borderline personality disorder (factors 3 and 4), somatoform disorder (factors 1 and 2), paranoid and dependent personality disorders (factors 2 and 4), and eating disorders (factors 1 and 4). Three correlated environmental factors were identified: axis II disorders, axis I internalizing disorders, and externalizing disorders versus anxiety disorders. Common axis I and II psychiatric disorders have a coherent underlying genetic structure that reflects two major dimensions: internalizing versus externalizing, and axis I versus axis II. The underlying structure of environmental influences is quite different. The organization of common psychiatric disorders into coherent groups results largely from genetic, not environmental, factors. These results should be interpreted in the context of unavoidable limitations of current statistical methods applied to this number of diagnostic categories.

  18. Calibration of three-axis magnetometers with differential evolution algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Pang, Hongfeng, E-mail: panghongfeng@126.com [College of Mechatronics Engineering and Automation, National University of Defense Technology, Changsha 410073 (China); Zhang, Qi [College of Mechatronics Engineering and Automation, National University of Defense Technology, Changsha 410073 (China); Wang, Wei [Northwest Institute of Nuclear Technology, Xian 710024 (China); Wang, Junya; Li, Ji; Luo, Shitu; Wan, Chengbiao; Chen, Dixiang; Pan, Mengchun; Luo, Feilu [College of Mechatronics Engineering and Automation, National University of Defense Technology, Changsha 410073 (China)

    2013-11-15

    The accuracy of three-axis magnetometers is influenced by different scale and bias of each axis and nonorthogonality between axes. One limitation of traditional iteration methods is that initial parameters influence the calibration, thus leading to the local optimal or wrong results. In this paper, a new method is proposed to calibrate three-axis magnetometers. To employ this method, a nonmagnetic rotation platform, a proton magnetometer, a DM-050 three-axis magnetometer and the differential evolution (DE) algorithm are used. The performance of this calibration method is analyzed with simulation and experiment. In simulation, the calibration results of DE, unscented Kalman filter (UKF), recursive least squares (RLS) and genetic algorithm (GA) are compared. RMS error using DE is least, which is reduced from 81.233 nT to 1.567 nT. Experimental results show that comparing with UKF, RLS and GA, the DE algorithm has not only the least calibration error but also the best robustness. After calibration, RMS error is reduced from 68.914 nT to 2.919 nT. In addition, the DE algorithm is not sensitive to initial parameters, which is an important advantage compared with traditional iteration algorithms. The proposed algorithm can avoid the troublesome procedure to select suitable initial parameters, thus it can improve the calibration performance of three-axis magnetometers. - Highlights: • The calibration results and robustness of UKF, GA, RLS and DE algorithm are analyzed. • Calibration error of DE is the least in simulation and experiment. • Comparing with traditional calibration algorithms, DE is not sensitive to initial parameters. • It can improve the calibration performance of three-axis magnetometers.

  19. Calibration of three-axis magnetometers with differential evolution algorithm

    International Nuclear Information System (INIS)

    Pang, Hongfeng; Zhang, Qi; Wang, Wei; Wang, Junya; Li, Ji; Luo, Shitu; Wan, Chengbiao; Chen, Dixiang; Pan, Mengchun; Luo, Feilu

    2013-01-01

    The accuracy of three-axis magnetometers is influenced by different scale and bias of each axis and nonorthogonality between axes. One limitation of traditional iteration methods is that initial parameters influence the calibration, thus leading to the local optimal or wrong results. In this paper, a new method is proposed to calibrate three-axis magnetometers. To employ this method, a nonmagnetic rotation platform, a proton magnetometer, a DM-050 three-axis magnetometer and the differential evolution (DE) algorithm are used. The performance of this calibration method is analyzed with simulation and experiment. In simulation, the calibration results of DE, unscented Kalman filter (UKF), recursive least squares (RLS) and genetic algorithm (GA) are compared. RMS error using DE is least, which is reduced from 81.233 nT to 1.567 nT. Experimental results show that comparing with UKF, RLS and GA, the DE algorithm has not only the least calibration error but also the best robustness. After calibration, RMS error is reduced from 68.914 nT to 2.919 nT. In addition, the DE algorithm is not sensitive to initial parameters, which is an important advantage compared with traditional iteration algorithms. The proposed algorithm can avoid the troublesome procedure to select suitable initial parameters, thus it can improve the calibration performance of three-axis magnetometers. - Highlights: • The calibration results and robustness of UKF, GA, RLS and DE algorithm are analyzed. • Calibration error of DE is the least in simulation and experiment. • Comparing with traditional calibration algorithms, DE is not sensitive to initial parameters. • It can improve the calibration performance of three-axis magnetometers

  20. ATX-LPA receptor axis in inflammation and cancer.

    Science.gov (United States)

    Liu, Shuying; Murph, Mandi; Panupinthu, Nattapon; Mills, Gordon B

    2009-11-15

    Lysophosphatidic acid (LPA, 1- or 2-acyl-sn-glycerol 3-phosphate) mediates a plethora of physiological and pathological activities via interactions with a series of high affinity G protein-coupled receptors (GPCR). Both LPA receptor family members and autotaxin (ATX/LysoPLD), the primary LPA-producing enzyme, are aberrantly expressed in many human breast cancers and several other cancer lineages. Using transgenic mice expressing either an LPA receptor or ATX, we recently demonstrated that the ATX-LPA receptor axis plays a causal role in breast tumorigenesis and cancer-related inflammation, further validating the ATX-LPA receptor axis as a rich therapeutic target in cancer.

  1. Nearly-off-axis transmissivity of Solc birefringent filters.

    Science.gov (United States)

    Zhou, Yu; Liu, Liren; Zhang, Juan; Liu, De'an; Luan, Zhu

    2003-04-01

    The characteristics of light propagating near the axis of a birefringent filter are studied. A generalized formulation to describe the nearly-off-axis transmissivity of a Solc birefringent filter is derived. On this basis, the polarization conoscopic figures of Solc filters with different numbers of birefringent plates are simulated. Furthermore the variation of spectral transmission with angle of incidence is analyzed, and the field-of-view transmissivity and the spectral transmissivity averaged with respect to the spread of incident light are given. Primary experiments for verification are also demonstrated.

  2. The properties of on-axis coupled structure RF gun

    CERN Document Server

    Oda, F; Nakayama, A; Koike, H; Tanabe, E

    2000-01-01

    Kawasaki Heavy Industries Ltd. (KHI) has developed the compact IR FEL device, which adopts a combination of a newly designed RF gun with a thermionic cathode and an alpha-magnet as an injector. The accelerating mode of the S-band RF gun is a pi/2 standing wave mode. The coupling cell is located on the beam axis, the so-called on-axis coupled structure (OCS). The cavity shape was designed by using electromagnetic field analytical codes. The OCS RF gun was manufactured and the electromagnetic properties were measured. The results show good agreement with the simulations.

  3. Research on Parameter Design of Multi - axis Hydrostatic Transmission Vehicle

    Directory of Open Access Journals (Sweden)

    Zhao Liang

    2017-01-01

    Full Text Available In order to obtain reasonable parameters in the design of driving system of multi-axis hydrostatic transmission vehicle, the working principle of single-side drive of hydrostatic transmission vehicle is introduced. The matching and control of engine and hydraulic pump are analyzed. According to the driving equation of vehicle, The driving force required for driving system is determined, and the parameters of hydraulic motor, hydraulic pump, system working pressure and braking system are designed and calculated, which provides the parameter design for driving system of multi-axis hydrostatic transmission Reliable theoretical basis.

  4. Targeting the gut-liver axis in cirrhosis

    DEFF Research Database (Denmark)

    Madsen, Bjørn S; Havelund, Troels; Krag, Aleksander

    2013-01-01

    The gut-liver axis in cirrhosis and portal hypertension is gaining increasing attention as a key pathophysiological mechanism responsible for progression of liver failure and development of complications such as spontaneous infections and hepatocellular carcinoma. Antibiotics and non-selective β......-blockers (NSBB) intercept this axis and each drug has proven efficacy in clinical trials. A synergistic effect is a hitherto unproven possibility. There is an increasing body of evidence supporting improved outcome with expanded use of NSBB and antibiotic therapy beyond current indications. This review addresses...

  5. Three axis vector atomic magnetometer utilizing polarimetric technique

    Energy Technology Data Exchange (ETDEWEB)

    Pradhan, Swarupananda, E-mail: spradhan@barc.gov.in, E-mail: pradhans75@gmail.com [Laser and Plasma Technology Division, Bhabha Atomic Research Centre, Mumbai 400085, India and Homi Bhabha National Institute, Department of Atomic Energy, Mumbai 400094 (India)

    2016-09-15

    The three axis vector magnetic field measurement based on the interaction of a single elliptically polarized light beam with an atomic system is described. The magnetic field direction dependent atomic responses are extracted by the polarimetric detection in combination with laser frequency modulation and magnetic field modulation techniques. The magnetometer geometry offers additional critical requirements like compact size and large dynamic range for space application. Further, the three axis magnetic field is measured using only the reflected signal (one polarization component) from the polarimeter and thus can be easily expanded to make spatial array of detectors and/or high sensitivity field gradient measurement as required for biomedical application.

  6. Microbiota-gut-brain axis and the central nervous system.

    Science.gov (United States)

    Zhu, Xiqun; Han, Yong; Du, Jing; Liu, Renzhong; Jin, Ketao; Yi, Wei

    2017-08-08

    The gut and brain form the gut-brain axis through bidirectional nervous, endocrine, and immune communications. Changes in one of the organs will affect the other organs. Disorders in the composition and quantity of gut microorganisms can affect both the enteric nervous system and the central nervous system (CNS), thereby indicating the existence of a microbiota-gut-brain axis. Due to the intricate interactions between the gut and the brain, gut symbiotic microorganisms are closely associated with various CNS diseases, such as Parkinson's disease, Alzheimer's disease, schizophrenia, and multiple sclerosis. In this paper, we will review the latest advances of studies on the correlation between gut microorganisms and CNS functions & diseases.

  7. The Microbiome-Gut-Brain Axis in Health and Disease.

    Science.gov (United States)

    Dinan, Timothy G; Cryan, John F

    2017-03-01

    Gut microbes are capable of producing most neurotransmitters found in the human brain. Evidence is accumulating to support the view that gut microbes influence central neurochemistry and behavior. Irritable bowel syndrome is regarded as the prototypic disorder of the brain-gut-microbiota axis that can be responsive to probiotic therapy. Translational studies indicate that certain bacteria may have an impact on stress responses and cognitive functioning. Manipulating the gut microbiota with psychobiotics, prebiotics, or even antibiotics offers a novel approach to altering brain function and treating gut-brain axis disorders, such as depression and autism. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. ATF Neutron Irradiation Program Irradiation Vehicle Design Concepts

    Energy Technology Data Exchange (ETDEWEB)

    Geringer, J. W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science and Technology Division; Katoh, Yutai [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science and Technology Division; Howard, Richard H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science and Technology Division; Cetiner, N. O. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science and Technology Division; Petrie, Christian M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science and Technology Division; Smith, Kurt R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science and Technology Division; McDuffee, J. M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science and Technology Division

    2016-03-01

    The Japan Atomic Energy Agency (JAEA) under the Civil Nuclear Energy Working Group (CNWG) is engaged in a cooperative research effort with the U.S. Department of Energy (DOE) to explore issues related to nuclear energy, including research on accident-tolerant fuels and materials for use in light water reactors. This work develops a draft technical plan for a neutron irradiation program on the candidate accident-tolerant fuel cladding materials and elements using the High Flux Isotope Reactor (HFIR). The research program requires the design of a detailed experiment, development of test vehicles, irradiation of test specimens, possible post irradiation examination and characterization of irradiated materials and the shipment of irradiated materials to Japan. This report discusses the conceptual design, the development and irradiation of the test vehicles.

  9. Regulation of food irradiation and detection of irradiated food

    International Nuclear Information System (INIS)

    Roberts, P.B.

    1998-01-01

    The main international standards for irradiated foods are those produced by the Codex Alimentarius Commission. The international regulatory environment is now favourable towards irradiated foods. Most countries still regulate on a food-by-food, case-by-case basis. However in Asia there is movement towards a Harmonised Regulation for Irradiated Foods. The WHO believes that irradiated foods may be safely irradiated at any dose above 10 kGy. This may lead to the Codex maximum dose being raised or abandoned. If this occurs there are opportunities to produce shelf-stable foods in lightweight packaging that last for years at room temperature. Detection methods for irradiated foods are now available and may assist to reassure consumers that labelling regulations can be enforced. (author)

  10. The wholesomeness of irradiated food

    International Nuclear Information System (INIS)

    Elias, P.S.; Matsuyama, A.

    1978-01-01

    It is apparent that there is a need for protection of the consumer and a need for governmental authorities to insure a safe and wholesome food supply for the population. Based on objective and scientific evidence regarding the safety of food irradiation, national and international health authorities are able to determine whether irradiated food is acceptable for human consumption. Following a thorough review of all available data, the Joint FAO/IAEA/WHO Expert Committee unconditionally approved wheat and ground wheat products and papaya irradiated for disingestation at a maximum dose of 100 krad, potatoes irradiated for sprout control at a maximum dose not exceeding 15 krad, and chicken irradiated at a maximum dose of 700 krad to reduce microbiological spoilage. Lastly, it unconditionally approved strawberries irradiated at a maximum dose of 300 krad to prolong storage. Onions at irradiated for sprout control at a maximum dose of 15 krad were temporarily approved, subject to preparation of further data on multigeneration reproduction studies on rats. Codfish and redfish eviscerated after irradiation at a maximum dose of 220 krad to reduce microbiological spoilage were also approved, based on the results of various studies in progress. Temporary, conditional approval of rice irradiated for insect disinfestation at a maximum dose of 100 krad was based on results of long-term studies on rats and monkies, available in the next review. Due to insufficient data, no decision regarding irradiated mushrooms was made. (Bell, E.)

  11. Gemstone dedicated gamma irradiation development

    Energy Technology Data Exchange (ETDEWEB)

    Omi, Nelson M.; Rela, Paulo R. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mails: nminoru@ipen.br; prela@ipen.br

    2007-07-01

    The gemstones gamma irradiation process to enhance the color is widely accepted for the jewelry industry. These gems are processed in conventional industrial gamma irradiation plant which are optimized for other purposes, using underwater irradiation devices with high rejection rate due to its poor dose uniformity. A new conception design, which states the working principles and manufacturing ways of the device, was developed in this work. The suggested device's design is based on the rotation of cylindrical baskets and their translation in circular paths inside and outside a cylindrical source rack as a planetary system. The device is meant to perform the irradiation in the bottom of the source storage pool, where the sources remain always shielded by the water layer. The irradiator matches the Category III IAEA classification. To verify the physical viability of the basic principle, tests with rotating cylindrical baskets were performed in the Multipurpose Irradiator constructed in the CTR, IPEN. Also, simulations using the CADGAMMA software, adapted to simulate underwater irradiations, were performed. With the definitive optimized irradiator, the irradiation quality will be enhanced with better dose control and the production costs will be significantly lower than market prices due to the intended treatment device's optimization. This work presents some optimization parameters and the expected performance of the irradiator. (author)

  12. Gemstone dedicated gamma irradiation development

    International Nuclear Information System (INIS)

    Omi, Nelson M.; Rela, Paulo R.

    2007-01-01

    The gemstones gamma irradiation process to enhance the color is widely accepted for the jewelry industry. These gems are processed in conventional industrial gamma irradiation plant which are optimized for other purposes, using underwater irradiation devices with high rejection rate due to its poor dose uniformity. A new conception design, which states the working principles and manufacturing ways of the device, was developed in this work. The suggested device's design is based on the rotation of cylindrical baskets and their translation in circular paths inside and outside a cylindrical source rack as a planetary system. The device is meant to perform the irradiation in the bottom of the source storage pool, where the sources remain always shielded by the water layer. The irradiator matches the Category III IAEA classification. To verify the physical viability of the basic principle, tests with rotating cylindrical baskets were performed in the Multipurpose Irradiator constructed in the CTR, IPEN. Also, simulations using the CADGAMMA software, adapted to simulate underwater irradiations, were performed. With the definitive optimized irradiator, the irradiation quality will be enhanced with better dose control and the production costs will be significantly lower than market prices due to the intended treatment device's optimization. This work presents some optimization parameters and the expected performance of the irradiator. (author)

  13. Consumer acceptance of irradiated foods

    International Nuclear Information System (INIS)

    Feenstra, M.H.; Scholten, A.H.

    1991-01-01

    Although the first experiments on food irradiation were carried out in 1916 in Sweden, food irradiation, is for consumers, a relatively new technology. From the sixties food irradiation has been applied more and more, so that the consumer movement has become alert to this technology. Since then a lot of controversies have arisen in the literature about wholesomeness, safety, effects, etc. Food irradiation is currently permitted on a small scale in about 30 countries; in some countries or states food irradiation has been put under a ban (e.g. Australia, New Zealand, New Jersey). The World Health Organization (WHO) and the Food and Agriculture Organization of the United Nations (FAO) have, however, chosen food irradiation as a safe and sound method for preserving and improving the safety of food. Reactions on the part of the consumer organizations of many countries are however not in favour of or are even opposed to food irradiation. In this chapter consumer acceptance related to technological developments is described, then the convergence of the consumer movement on public opinion and concern on food irradiation is discussed. The need for labelling of irradiated food products is discussed and finally recommendations are given of ways to change consumers attitudes to food irradiation. (author)

  14. Total body irradiation: current indications

    International Nuclear Information System (INIS)

    Giraud, P.; Danhier, S.; Dubray, B.; Cosset, J.M.

    1998-01-01

    The choice of dose and fractionation for total body irradiation is made difficult by the large number of considerations to be taken into account. The outcome of bone marrow transplantation after total body irradiation can be understood in terms of tumor cell killing, engraftment, and normal tissue damage, each of these endpoints being influenced by irradiation-, disease-, transplant-, and patient- related factors. Interpretation of clinical data is further hampered by the overwhelming influence of logistic constraints, the small numbers of randomized studies, and the concomitant variations in total dose and fraction size or dose rate. So far, three cautious conclusions can be drawn in order to tentatively adapt the total body irradiation schedule to clinically-relevant situations. Firstly, the organs at risk for normal tissue damage (lung, liver, lens, kidney) are protected by delivering small doses per fraction at low dose rate. This suggests that, when toxicity is at stake (e.g. in children), fractionated irradiation should be preferred, provided that inter-fraction intervals are long enough. Secondly, fractionated irradiation should be avoided in case of T-cell depleted transplant, given the high risk of graft rejection in this setting. An alternative would be to increase total (or fractional) dose of fractionated total body irradiation, but this approach is likely to induce more normal tissue toxicity. Thirdly, clinical data have shown higher relapse rates in chronic myeloid leukemia after fractionated or low dose rate total body irradiation, suggesting that fractionated irradiation should not be recommended, unless total (or fractional) dose is increased. Total body irradiation-containing regimens, primarily cyclophosphamide / total body irradiation, are either equivalent to or better than the chemotherapy-only regimens, primarily busulfan / cyclophosphamide. Busulfan / cyclophosphamide certainly represents a reasonable alternative, especially in patients who

  15. Facts about food irradiation: Microbiological safety of irradiated food

    International Nuclear Information System (INIS)

    1991-01-01

    This fact sheet considers the microbiological safety of irradiated food, with especial reference to Clostridium botulinum. Irradiated food, as food treated by any ''sub-sterilizing'' process, must be handled, packaged and stored following good manufacturing practices to prevent growth and toxin production of C. botulinum. Food irradiation does not lead to increased microbiological hazards, nor can it be used to save already spoiled foods. 4 refs

  16. Property changes in graphite irradiated at changing irradiation temperature

    International Nuclear Information System (INIS)

    Price, R.J.; Haag, G.

    1979-07-01

    Design data for irradiated graphite are usually presented as families of isothermal curves showing the change in physical property as a function of fast neutron fluence. In this report, procedures for combining isothermal curves to predict behavior under changing irradiation temperatures are compared with experimental data on irradiation-induced changes in dimensions, Young's modulus, thermal conductivity, and thermal expansivity. The suggested procedure fits the data quite well and is physically realistic

  17. Irradiation probe and laboratory for irradiated material evaluation

    International Nuclear Information System (INIS)

    Smutny, S.; Kupca, L.; Beno, P.; Stubna, M.; Mrva, V.; Chmelo, P.

    1975-09-01

    The survey and assessment are given of the tasks carried out in the years 1971 to 1975 within the development of methods for structural materials irradiation and of a probe for the irradiation thereof in the A-1 reactor. The programme and implementation of laboratory tests of the irradiation probe are described. In the actual reactor irradiation, the pulse tube length between the pressure governor and the irradiation probe is approximately 20 m, the diameter is 2.2 mm. Temperature reaches 800 degC while the pressure control system operates at 20 degC. The laboratory tests (carried out at 20 degC) showed that the response time of the pressure control system to a stepwise pressure change in the irradiation probe from 0 to 22 at. is 0.5 s. Pressure changes were also studied in the irradiation probe and in the entire system resulting from temperature changes in the irradiation probe. Temperature distribution in the body of the irradiation probe heating furnace was determined. (B.S.)

  18. Gamma irradiation service in Mexico

    International Nuclear Information System (INIS)

    Liceaga C, G.; Martinez A, L.; Mendez T, D.; Ortiz A, G.; Olvera G, R.

    1997-01-01

    In 1980 it was installed in Mexico, on the National Institute of Nuclear Research, an irradiator model J S-6500 of a canadian manufacture. Actually, this is the greatest plant in the Mexican Republic that offers a gamma irradiation process at commercial level to diverse industries. However, seeing that the demand for sterilize those products were not so much as the irradiation capacity it was opted by the incursion in other types of products. During 17 years had been irradiated a great variety of products grouped of the following form: dehydrated foods, disposable products for medical use, cosmetics, medicaments, various. Nowadays the capacity of the irradiator is saturated virtue of it is operated the 24 hours during the 365 days of the year and only its operation is suspended by the preventive and corrective maintenance. However, the fresh food market does not be attended since this irradiator was designed for doses greater than 10 kGy (1.0 Mrad)

  19. Food irradiation scenario in India

    International Nuclear Information System (INIS)

    Thomas, Paul

    1998-01-01

    Over 3 decades of research and developmental effort in India have established the commercial potential for food irradiation to reduce post-harvest losses and to ensure food safety. Current regulations permit irradiation of onions, potatoes and spices for domestic consumption and operation of commercial irradiators for treatment of food. In May 1997 draft rules have been notified permitting irradiation of several additional food items including rice, wheat products, dry fruits, mango, meat and poultry. Consumers and food industry have shown a positive attitude to irradiated foods. A prototype commercial irradiator for spices set up by Board of Radiation and Isotope Technology (BRIT) is scheduled to commence operation in early 1998. A commercial demonstration plant for treatment of onions is expected to be operational in the next 2 years in Lasalgaon, Nashik district. (author)

  20. Status of irradiation capsule design

    International Nuclear Information System (INIS)

    Nagata, Hiroshi; Yamaura, Takayuki; Nagao, Yoshiharu

    2013-01-01

    For the irradiation test after the restart of JMTR, further precise temperature control and temperature prediction are required. In the design of irradiation capsule, particularly sophisticated irradiation temperature prediction and evaluation are urged. Under such circumstance, among the conventional design techniques of irradiation capsule, the authors reviewed the evaluation method of irradiation temperature. In addition, for the improvement of use convenience, this study examined and improved FINAS/STAR code in order to adopt the new calculation code that enables a variety of analyses. In addition, the study on the common use of the components for radiation capsule enabled the shortening of design period. After the restart, the authors will apply this improved calculation code to the design of irradiation capsule. (A.O.)

  1. Market testing of irradiated food

    International Nuclear Information System (INIS)

    Duc, Ho Minh

    2001-01-01

    Viet Nam has emerged as one of the three top producers and exporters of rice in the world. Tropical climate and poor infrastructure of preservation and storage lead to huge losses of food grains, onions, dried fish and fishery products. Based on demonstration irradiation facility pilot scale studies and marketing of irradiated rice, onions, mushrooms and litchi were successfully undertaken in Viet Nam during 1992-1998. Irradiation technology is being used commercially in Viet Nam since 1991 for insect control of imported tobacco and mould control of national traditional medicinal herbs by both government and private sectors. About 30 tons of tobacco and 25 tons of herbs are irradiated annually. Hanoi Irradiation Centre has been continuing open house practices for visitors from school, universities and various different organizations and thus contributed in improved public education. Consumers were found to prefer irradiated rice, onions, litchi and mushrooms over those nonirradiated. (author)

  2. Irradiation of fruit and vegetables

    International Nuclear Information System (INIS)

    O'Beirne, David

    1987-01-01

    There is likely to be less economic incentive to irradiate fruits and vegetables compared with applications which increase the safety of foods such as elimination of Salmonella or decontamination of food ingredients. Of the fruit and vegetable applications, irradiation of mushrooms may offer the clearest economic benefits in North-Western Europe. The least likely application appears to be sprout inhibition in potatoes and onions, because of the greater efficiency and flexibility of chemical sprout inhibitors. In the longer-term, combinations between irradiation/MAP/other technologies will probably be important. Research in this area is at an early stage. Consumer attitudes to food irradiation remain uncertain. This will be a crucial factor in the commercial application of the technology and in the determining the balance between utilisation of irradiation and of technologies which compete with irradiation. (author)

  3. Gamma irradiation of fruits

    International Nuclear Information System (INIS)

    Beyers, M.

    1983-08-01

    At a Joint FAO/IAEA/WHO Expert Committee on Food Irradiation (JECFI) meeting held in 1976, recommendations were made to rationalize the unnecessarily elaborate wholesomeness evaluation procedures for irradiated foodstuffs. Irradiation at the commercially recommended doses did not adversely affect the constituents of mangoes, papayas, litchis and strawberries at the edible-ripe stage. These favourable radiation-chemical results justified the development of a theoretical model mango which could be used for extrapolation of wholesomeness data from an individual fruit species to all others within the same diet class. Several mathematical models of varying orders of sophistication were evolved. In all of them, it was assumed that the radiant energy entering the system reacted solely with water. The extent of the reaction of the other components of the model fruit with the primary water radicals was then determined. No matter which mathematical treatment was employed, it was concluded that the only components which would undergo significant modification would be the sugars. In order to extrapolate these data from the mango to other fruits, mathematical models of three fruits containing less sugar than the mango, viz. the strawberry, tomato and lemon, were compiled. With these models, the conclusion was reached that the theoretical degradation spectra of these fruits were qualitatively similar to the degradation pattern of the model mango. Theory was again substantiated by the practical demonstration of the protective effect of the sugars in the tomato and lemon. The decrease in radiation damage was enhanced by the mutual protection of the components of the whole synthetic fruits with ultimate protection being afforded by the biological systems of the real fruits

  4. Desinfestation of soybeans by irradiation

    International Nuclear Information System (INIS)

    Alvarez, M.; Prieto, E.; Mesa, J.; Fraga, R.; Fung, V.

    1996-01-01

    The effect of irradiation with the doses 0.5 and 1.0 kGy on desinfestation of soy beans and on important chemical compounds of this product was studied in this paper. The results showed the effectiveness of applied doses in the control of insect pests of soy beans during its storage and total proteins, fat and moisture and also the identity and quality characteristics of oil extrated from irradiated product which were not change by irradiation [es

  5. Canadian perspectives on food irradiation

    International Nuclear Information System (INIS)

    Kunstadt, P.

    1990-01-01

    Canada has been in the forefront of irradiation technology for over 30 years. Some 83 of the 147 irradiators used worldwide are Canadian-built, yet Canadian food processors have been very slow to use the technology. This paper is an update on the food irradiation regulatory situation in Canada and the factors that influence it. It also reviews some significant non-regulatory developments. (author)

  6. National symposium on food irradiation

    International Nuclear Information System (INIS)

    1979-10-01

    This report contains abstracts of papers delivered at the National symposium on food irradiation held in Pretoria. The abstracts have been grouped into the following sections: General background, meat, agricultural products, marketing and radiation facilities - cost and plant design. Each abstract has been submutted separately to INIS. Tables listing irradiated food products cleared for human consumption in different countries are given as well as a table listing those irradiated food items that have been cleared in South Africa

  7. On the Turbulent Mixing in Horizontal Axis Wind Turbine Wakes

    NARCIS (Netherlands)

    Lignarolo, L.E.M.

    2016-01-01

    The wake flow of a horizontal axis wind turbine is characterised by lower wind speed and higher turbulence than the free-stream conditions. When clustered in large wind farms, wind turbines regularly operate inside the wake of one or more upstream machines. This is a major cause of energy production

  8. An improved computer controlled triple-axis neutron spectrometer

    International Nuclear Information System (INIS)

    Cooper, M.J.; Hall, J.W.; Hutchings, M.T.

    1975-07-01

    A description is given of the computer-controlled triple-axis neutron spectrometer installed at the PLUTO reactor at Harwell. The reasons for an nature of recent major improvements are discussed. Following a general description of the spectrometer, details are then given of the new computerised control system, including the functions of the various programs which are now available to the user. (author)

  9. Evidence of a liver-alpha cell axis in humans

    DEFF Research Database (Denmark)

    Wewer Albrechtsen, Nicolai J; Færch, Kristine; Jensen, Troels M

    2018-01-01

    in plasma γ-glutamyltransferase levels. CONCLUSIONS/INTERPRETATION: This cross-sectional study supports the existence of a liver-alpha cell axis in humans: glucagon regulates plasma levels of amino acids, which in turn feedback to regulate the secretion of glucagon. With hepatic insulin resistance...

  10. The GH/IGF-1 axis in ageing and longevity

    Science.gov (United States)

    List, Edward O.; Berryman, Darlene E.; Murrey, John W.

    2014-01-01

    Secretion of growth hormone (GH), and consequently that of insulin-like growth factor 1 (IGF-1), declines over time until only low levels can be detected in individuals aged ≥60 years. This phenomenon, which is known as the ‘somatopause’, has led to recombinant human GH being widely promoted and abused as an antiageing drug, despite lack of evidence of efficacy. By contrast, several mutations that decrease the tone of the GH/IGF-1 axis are associated with extended longevity in mice. In humans, corresponding or similar mutations have been identified, but whether these mutations alter longevity has yet to be established. The powerful effect of reduced GH activity on lifespan extension in mice has generated the hypothesis that pharmaceutically inhibiting, rather than increasing, GH action might delay ageing. Moreover, mice as well as humans with reduced activity of the GH/IGF-1 axis are protected from cancer and diabetes mellitus, two major ageing-related morbidities. Here, we review data on mouse strains with alterations in the GH/IGF-1 axis and their effects on lifespan. The outcome of corresponding or similar mutations in humans is described, as well as the potential mechanisms underlying increased longevity and the therapeutic benefits and risks of medical disruption of the GH/IGF-1 axis in humans. PMID:23591370

  11. Comparison of aerodynamic models for Vertical Axis Wind Turbines

    NARCIS (Netherlands)

    Simao Ferreira, C.J.; Aagaard Madsen, H.; Barone, M.; Roscher, B.; Deglaire, P.; Arduin, I.

    2014-01-01

    Multi-megawatt Vertical Axis Wind Turbines (VAWTs) are experiencing an increased interest for floating offshore applications. However, VAWT development is hindered by the lack of fast, accurate and validated simulation models. This work compares six different numerical models for VAWTS: a multiple

  12. On-axis conoscopic holography without a conjugate image.

    Science.gov (United States)

    Mugnier, L M; Sirat, G Y

    1992-02-15

    We present a method for removing the conjugate image in an incoherent-light holographic technique, namely, on-axis conoscopic holography. The point-spread function that we obtain is that of a complex Gabor zone pattern, which thus should allow good-quality reconstructions of objects. Experimental results are also presented, which confirm the validity of this method.

  13. QRS Axis deviation in Nigeria women during normal pregnancy ...

    African Journals Online (AJOL)

    The effect of pregnancy on the heart rate, respiratory rate, QRS axis and QRS complex duration of the ECG was investigated din 41 pregnant compared to 39 non pregnant age and height matched Nigeria subjects. Results obtained show that pregnancy had no significant effect (p>0.05) on heart rate, respiratory rate and ...

  14. The enteroinsular axis in dipeptidyl peptidase IV-negative rats

    DEFF Research Database (Denmark)

    Pederson, Raymond; Kieffer, T J; Pauly, R

    1996-01-01

    were used in the current investigation as a model for examining the enteroinsular axis under conditions in which normal inactivation of GIP and GLP-1(7-36) does not occur. This was assessed by comparing GIP and GLP-1(7-36) responses following oral glucose in normal versus DPIV-deficient Fischer rats...

  15. The apolipoprotein m-sphingosine-1-phosphate axis

    DEFF Research Database (Denmark)

    Arkensteijn, Bas W C; Berbée, Jimmy F P; Rensen, Patrick C N

    2013-01-01

    -receptor-1, affecting the function of endothelial cells, and apoM-deficient mice display impaired endothelial permeability in the lung. This review will focus on the putative biological roles of the new apoM-S1P axis in relation to lipoprotein metabolism, lipid disorders and atherosclerosis....

  16. Genetic loci mapping for ear axis weight using recombinant inbred ...

    African Journals Online (AJOL)

    Ear axis weight (EAW) is one of the important agronomic traits in maize (Zea mays L.), related to yield. To understand its genetic basis, a recombinant inbred line (RIL) population, derived from the cross Mo17 × Huangzao4, was used for quantitative trait locus mapping (QTL) for EAW under high and low nitrogen (N) regimes.

  17. Analysis of horizontal axis wind turbine blade using CFD | Nigam ...

    African Journals Online (AJOL)

    Blade is very essential part of HAWT (horizontal axis wind turbine). Forces for Lift and drag on the blade has an important role in the wind turbine performance. The main purpose of this work is to perform CFD analysis of a blade and airfoil of wind turbine using k-ω SST model. In this present study NACA 634 -221 airfoil ...

  18. Comparison of aerodynamic models for Vertical Axis Wind Turbines

    DEFF Research Database (Denmark)

    Ferreira, C. Simão; Aagaard Madsen, Helge; Barone, M.

    2014-01-01

    Multi-megawatt Vertical Axis Wind Turbines (VAWTs) are experiencing an increased interest for floating offshore applications. However, VAWT development is hindered by the lack of fast, accurate and validated simulation models. This work compares six different numerical models for VAWTS: a multipl...

  19. Super earth explorer: a coronagraphic off-axis space telescope

    NARCIS (Netherlands)

    Stam, D.; Keller, C.U.

    2009-01-01

    The Super-Earth Explorer is an Off-Axis Space Telescope (SEE-COAST) designed for high contrast imaging. Its scientific objective is to make the physico-chemical characterization of exoplanets possibly down to 2 Earth radii. For that purpose it will analyze the spectral and polarimetric properties of

  20. Analysis of off-axis tension test of wood specimens

    Science.gov (United States)

    Jen Y. Liu

    2002-01-01

    This paper presents a stress analysis of the off-axis tension test of clear wood specimens based on orthotropic elasticity theory. The effects of Poisson's ratio and shear coupling coefficient on stress distribution are analyzed in detail. The analysis also provides a theoretical foundation for the selection of a 10° grain angle in wood specimens for the...

  1. Brain-gut-microbiota axis in Parkinson's disease.

    Science.gov (United States)

    Mulak, Agata; Bonaz, Bruno

    2015-10-07

    Parkinson's disease (PD) is characterized by alpha-synucleinopathy that affects all levels of the brain-gut axis including the central, autonomic, and enteric nervous systems. Recently, it has been recognized that the brain-gut axis interactions are significantly modulated by the gut microbiota via immunological, neuroendocrine, and direct neural mechanisms. Dysregulation of the brain-gut-microbiota axis in PD may be associated with gastrointestinal manifestations frequently preceding motor symptoms, as well as with the pathogenesis of PD itself, supporting the hypothesis that the pathological process is spread from the gut to the brain. Excessive stimulation of the innate immune system resulting from gut dysbiosis and/or small intestinal bacterial overgrowth and increased intestinal permeability may induce systemic inflammation, while activation of enteric neurons and enteric glial cells may contribute to the initiation of alpha-synuclein misfolding. Additionally, the adaptive immune system may be disturbed by bacterial proteins cross-reacting with human antigens. A better understanding of the brain-gut-microbiota axis interactions should bring a new insight in the pathophysiology of PD and permit an earlier diagnosis with a focus on peripheral biomarkers within the enteric nervous system. Novel therapeutic options aimed at modifying the gut microbiota composition and enhancing the intestinal epithelial barrier integrity in PD patients could influence the initial step of the following cascade of neurodegeneration in PD.

  2. Microbiota-Brain-Gut Axis and Neurodegenerative Diseases.

    Science.gov (United States)

    Quigley, Eamonn M M

    2017-10-17

    The purposes of this review were as follows: first, to provide an overview of the gut microbiota and its interactions with the gut and the central nervous system (the microbiota-gut-brain axis) in health, second, to review the relevance of this axis to the pathogenesis of neurodegenerative diseases, such as Parkinson's disease, and, finally, to assess the potential for microbiota-targeted therapies. Work on animal models has established the microbiota-gut-brain axis as a real phenomenon; to date, the evidence for its operation in man has been limited and has been confronted by considerable logistical challenges. Animal and translational models have incriminated a disturbed gut microbiota in a number of CNS disorders, including Parkinson's disease; data from human studies is scanty. While a theoretical basis can be developed for the use of microbiota-directed therapies in neurodegenerative disorders, support is yet to come from high-quality clinical trials. In theory, a role for the microbiota-gut-brain axis is highly plausible; clinical confirmation is awaited.

  3. Microbiota regulation of the Mammalian gut-brain axis.

    Science.gov (United States)

    Burokas, Aurelijus; Moloney, Rachel D; Dinan, Timothy G; Cryan, John F

    2015-01-01

    The realization that the microbiota-gut-brain axis plays a critical role in health and disease has emerged over the past decade. The brain-gut axis is a bidirectional communication system between the central nervous system (CNS) and the gastrointestinal tract. Regulation of the microbiota-brain-gut axis is essential for maintaining homeostasis, including that of the CNS. The routes of this communication are not fully elucidated but include neural, humoral, immune, and metabolic pathways. A number of approaches have been used to interrogate this axis including the use of germ-free animals, probiotic agents, antibiotics, or animals exposed to pathogenic bacterial infections. Together, it is clear that the gut microbiota can be a key regulator of mood, cognition, pain, and obesity. Understanding microbiota-brain interactions is an exciting area of research which may contribute new insights into individual variations in cognition, personality, mood, sleep, and eating behavior, and how they contribute to a range of neuropsychiatric diseases ranging from affective disorders to autism and schizophrenia. Finally, the concept of psychobiotics, bacterial-based interventions with mental health benefit, is also emerging. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. The Minimal Model of the Hypothalamic-Pituitary-Adrenal Axis

    DEFF Research Database (Denmark)

    Vinther, Frank; Andersen, Morten; Ottesen, Johnny T.

    2011-01-01

    from an unstable fixed point with complex eigenvalues with a positive real parts and a non-zero imaginary parts. The first part of the paper describes the general considerations to be obeyed for a mathematical model of the HPA axis. In this paper we only include the most widely accepted mechanisms...

  5. Phytochemicals for taming agitated immune-endocrine-neural axis.

    Science.gov (United States)

    Patel, Seema

    2017-07-01

    Homeostasis of immune-endocrine-neural axis is paramount for human health. If this axis gets agitated due to age, genetic variations, environmental exposures or lifestyle assaults, a cascade of adverse reactions occurs in human body. Cytokines, hormones and neurotransmitters, the effector molecules of this axis behave erratically, leading to a gamut of neural, endocrine, autoimmune, and metabolic diseases. Current panel of drugs can tackle some of them but not in a sustainable, benign way as a myriad of side effects, causal of them have been documented. In this context, phytochemicals, the secondary metabolites of plants seem beneficial. These bioactive constituents encompassing polyphenols, alkaloids, flavonoids, terpenoids, tannins, lignans, stilbenoids (resveratrol), saponins, polysaccharides, glycosides, and lectins etc. have been proven to exert antioxidant, anti-inflammatory, hypolipidemic, hypotensive, antidiabetic, anticancer, immunomodulatory, anti-allergic, analgesic, hepatoprotective, neuroprotective, dermatoprotective, and antimicrobial properties, among a litany of other biological effects. This review presents a holistic perspective of common afflictions resultant of immune-endocrine-neural axis disruption, and the phytochemicals capable of restoring their normalcy and mitigating the ailments. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  6. Local charge measurement using off-axis electron holography

    DEFF Research Database (Denmark)

    Beleggia, Marco; Gontard, L.C.; Dunin-Borkowski, R.0E.

    2016-01-01

    A model-independent approach based on Gauss’ theorem for measuring the local charge in a specimen from an electron-optical phase image recorded using off-axis electron holography was recently proposed. Here, we show that such a charge measurement is reliable when it is applied to determine...

  7. Perspectives of food irradiation

    International Nuclear Information System (INIS)

    Miettinen, J.K.

    1974-01-01

    Food preservation by means of ionizing radiation has been technically feasible for more than a decade. Its utilization could increase food safety, extend the transport and shell life of foods, cut food losses, and reduce dependence upon chemical additives. The prime obstacles have been the strict safety requirements set by health authorities to this preservation method and the high costs of the long-term animal tests necessary to fulfil these requirements. An International Food Irradiation Project, expected to establish the toxicological safety of 10 foods by about 1976, is described in some detail. (author)

  8. Neutron irradiation therapy machine

    International Nuclear Information System (INIS)

    1980-01-01

    Conventional neutron irradiation therapy machines, based on the use of cyclotrons for producing neutron beams, use a superconducting magnet for the cyclotron's magnetic field. This necessitates complex liquid He equipment and presents problems in general hospital use. If conventional magnets are used, the weight of the magnet poles considerably complicates the design of the rotating gantry. Such a therapy machine, gantry and target facilities are described in detail. The use of protons and deuterons to produce the neutron beams is compared and contrasted. (U.K.)

  9. Irradiated fuel reprocessing

    International Nuclear Information System (INIS)

    Ruiz, C.P.; Peterson, J.P. Jr.

    1977-01-01

    A process for separately recovering uranium, plutonium and neptunium substantially free of fission products from irradiated nuclear fuel is presented in which the fuel is dissolved in a strong mineral acid forming an aqueous dissolved nuclear fuel solution and treated to separate the uranium, plutonium and neptunium therefrom substantially free of said fission products by the sequential steps of solvent extraction, ion exchange and fluorination. The process has an improvement comprising the addition of a sufficient quantity of an additive of a stable metallic complex to the aqueous dissolved nuclear fuel solution prior to solvent extraction. This achieves improved purity of the separated uranium, plutonium and neptunium

  10. Shiva target irradiation facility

    International Nuclear Information System (INIS)

    Manes, K.R.; Ahlstrom, H.G.; Coleman, L.W.; Storm, E.K.; Glaze, J.A.; Hurley, C.A.; Rienecker, F.; O'Neal, W.C.

    1977-01-01

    The first laser/plasma studies performed with the Shiva laser system will be two sided irradiations extending the data obtained by other LLL lasers to higher powers. The twenty approximately 1 TW laser pulses will reach the target simultaneously from above and below in nested pentagonal clusters. The upper and lower clusters of ten beams each are radially polarized so that they strike the target in p-polarization and maximize absorption. This geometry introduces laser system isolation problems which will be briefly discussed. The layout and types of target diagnostics will be described and a brief status report on the facility given

  11. Irradiation of northwest agricultural products

    Science.gov (United States)

    Eakin, D. E.; Tingey, G. I.

    1985-02-01

    Irradiation of food for disinfestation and preservation is increasing in importance because of increasing restrictions on various chemical treatments. Irradiation treatment is of particular interest in the Northwest because of a growing supply of agricultural products and the need to develop new export markets. Several products have, or could potentially have, significant export markets if stringent insect ocntrol procedures are developed and followed. Due to the recognized potential benefits of irradiation, this program was conducted to evaluate the benefits of using irradiation on Northwest agricultural products. Commodities currently included in the program are cherries, apples, asparagus, spices, hay, and hides.

  12. Food irradiation and the consumer

    International Nuclear Information System (INIS)

    Thomas, P.A.

    1990-01-01

    The poster presents a review of research work undertaken on the perception and understanding that consumers have of food irradiation. Food irradiation is not a revolutionary new food processing technique, in fact it is probably one of the most investigated methods presently available. Many countries such as Belgium, France, Denmark, Italy, Spain, the Netherlands and the United States of America permit food irradiation. In Britain it is presently banned although this is currently under review. Awareness of food irradiation by the general public in Britain, although not extensively researched would appear to be increasing, especially in the light of recent media coverage. New quantitative and qualitative work indicates that the general public are concerned about the safety and effectiveness of food irradiation. Research has shown that a large proportion of consumers in Britain, if given the opportunity to purchase irradiated food, would not do so. Further exploration into this response revealed the fact that consumers are confused over what food irradiation is. In addition, there is concern over the detection of irradiated food. The views presented in this paper, of the consumer reaction to irradiated food are of great importance to those involved in the food industry and industries allied to it, which are ultimately dependent on the consumer for their commercial survival. (author)

  13. International Developments of Food Irradiation

    International Nuclear Information System (INIS)

    Loaharanu, P.

    1997-01-01

    Food irradiation is increasingly accepted and applied in many countries in the past decade. Through its use, food losses and food-borne diseases can be reduced significantly, and wider trade in many food items can be facilitated. The past five decades have witnessed a positive evolution on food irradiation according to the following: 1940's: discovery of principles of food irradiation; 1950's: initiation of research in advanced countries; 1960's: research and development were intensified in some advanced and developing countries; 1970's: proof of wholesomeness of irradiated foods; 1980's: establishment of national regulations; 1990's: commercialization and international trade. (Author)

  14. Societal benefits of food irradiation

    International Nuclear Information System (INIS)

    Prakash, Anuradha

    2013-01-01

    Food irradiation has a direct impact on society by reducing the occurrence of food-borne illness, decreasing food spoilage and waste, and facilitating global trade. Food irradiation is approved in 40 countries around the world to decontaminate food of disease and spoilage causing microorganisms, sterilize insect pests, and inhibit sprouting. A recent estimate suggests that 500,000 metric of food is currently irradiated worldwide, primarily to decontaminate spices. Since its first use in the 1960s the use of irradiation for food has grown slowly, but it remains the major technology of choice for certain applications. The largest growth sector in recent years has been phytosanitary irradiation of fruit to disinfest fruit intended for international shipment. For many countries which have established strict quarantine standards, irradiation offers as an effective alternative to chemical fumigants some of which are being phased out due to their effects on the ozone layer. Insects can be sterilized at very low dose levels, thus quality of fruit can be maintained. Irradiation is also highly effective in destroying microbial pathogens such as Salmonella spp., E. coli, and Listeria, hence its application for treatment of spices, herbs, dried vegetables, frozen seafood, poultry, and meat and its contribution to reducing foodborne illnesses. Unfortunately the use of irradiation for improving food safety has been under-exploited. This presentation will provide details on the use, benefits, opportunities, and challenges of food irradiation. (author)

  15. International Developments of Food Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Loaharanu, P. [Head, Food Preservation Section, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, Wagramerstr. 5, A-1400, Vienna (Austria)

    1997-12-31

    Food irradiation is increasingly accepted and applied in many countries in the past decade. Through its use, food losses and food-borne diseases can be reduced significantly, and wider trade in many food items can be facilitated. The past five decades have witnessed a positive evolution on food irradiation according to the following: 1940`s: discovery of principles of food irradiation; 1950`s: initiation of research in advanced countries; 1960`s: research and development were intensified in some advanced and developing countries; 1970`s: proof of wholesomeness of irradiated foods; 1980`s: establishment of national regulations; 1990`s: commercialization and international trade. (Author)

  16. Commercial implementation of food irradiation

    International Nuclear Information System (INIS)

    Welt, M.A.

    1985-01-01

    Recent positive developments in regulatory matters involving food irradiation appear to be opening the door to commercial implementation of the technology. Experience gained over five years in operating multi-purpose food irradiation facilities in the United States have demonstrated the technical and economic feasibility of the radiation preservation of food for a wide variety of purposes. Public education regarding food irradiation has been intensified especially with the growing favorable involvement of food trade associations, the USDA, and the American Medical Association. After 41 years of development effort, food irradiation will become a commercial reality in 1985. (author)

  17. Irradiation's promise: fewer foodborne illnesses?

    International Nuclear Information System (INIS)

    Roberts, T.

    1986-01-01

    Food irradiation offers a variety of potential benefits to the food supply. It can delay ripening and sprouting of fruits and vegetables, and substitute for chemical fumigants to kill insects. However, one of the most important benefits of food irradiation is its potential use for destroying microbial pathogens that enter the food supply, including the two most common disease causing bacteria: salmonella and campylobacter. Animal products are one of the primary carriers of pathogens. Food borne illnesses are on the rise, and irradiation of red meats and poultry could significantly reduce their occurrence. Food irradiation should be examined more closely to determine its possible benefits in curtailing microbial diseases

  18. JRR-4 medical irradiation facility

    Energy Technology Data Exchange (ETDEWEB)

    Torii, Y.; Yamamoto, K.; Hori, N.; Kumada, H.; Horiguchi, Y. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-11-01

    JAERI started Boron Neutron Capture Therapy (BNCT) at JRR-2 in 1990. JRR-2 was performed 33 BNCT until 1996 when JRR-2 operation was terminated for decommissioning the reactor. JRR-4 was constructed to research the reactor shielding of the first Japanese nuclear ship ''Mutsu'' in 1965. JRR-4 was modified for reducing fuel enrichment and constructing a new medical irradiation facility at 1997 when after the terminating operation of JRR-2. The medical irradiation facility is especially using for BNCT of brain cancer. JRR-4 medical irradiation facility was designed for both using of thermal neutron beam and epi-thermal neutron. Thermal neutron is using for conventional Japanese BNCT as inter operative irradiation therapy. Epi-thermal neutron beam will be using advanced BNCT for deep cancer and without craniotomy operation for irradiation at the facility. The first medical irradiation for BNCT of JRR-4 was carried out on October 25, 1999. Since then, seven times of irradiation was performed by the end of June 2000. In BNCT irradiation, boron concentration and thermal flux measurements were performed by JAERI. Boron concentration of patient brood was measured using prompt gamma ray analysis technique. Thermal neutron flux was measured by gold wire activation method using beta - gamma coincidence counting system. There data were furnished to medical doctor for determination the irradiation time of BNCT. (author)

  19. Status of food irradiation worldwide

    International Nuclear Information System (INIS)

    Loaharanu, P.

    1992-01-01

    The past four decades have witnessed the steady development of food irradiation technology - from laboratory-scale research to full-scale commercial application. The present status of this technology, approval for processing food items in 37 countries and commerical use of irradiated food in 24 countries, will be discussed. The trend in the use of irradiation to overcome certain trade barriers such as quarantine and hygiene will be presented. Emphasis will be made on the use of irradiation as an alternative to chemical treatments of food. (orig.) [de

  20. GRB 170817A: a short GRB seen off-axis

    Science.gov (United States)

    He, Xin-Bo; Tam, Pak-Hin Thomas; Shen, Rong-Feng

    2018-04-01

    The angular distribution of gamma-ray burst (GRB) jets is not yet clear. The observed luminosity of GRB 170817A is the lowest among all known short GRBs, which is best explained by the fact that our line of sight is outside of the jet opening angle, θ obs > θ j , where θ obs is the angle between our line of sight and the jet axis. As inferred by gravitational wave observations, as well as radio and X-ray afterglow modeling of GRB 170817A, it is likely that θ obs ∼ 20° – 28°. In this work, we quantitatively consider two scenarios of angular energy distribution of GRB ejecta: a top-hat jet and a structured jet with a power law index s. For the top-hat jet model, we get a large θ j (e.g., θ j > 10°), a rather high local (i.e., z 7.5 × 104, keV (∼500, keV for a typical short GRB). For the structured jet model, we use θ obs to give limits on s and θj for typical on-axis luminosity of a short GRB (e.g., 1049 erg s‑1 ∼ 1051 erg s‑1), and a low on-axis luminosity case (e.g., 1049 erg s‑1) gives more reasonable values of s. The structured jet model is more feasible for GRB 170817A than the top-hat jet model due to the rather high local short GRB rate, and the extremely high on-axis E peak,0 almost rules out the top-hat jet model. GRB 170817A is likely a low on-axis luminosity GRB (1049 erg s‑1) with a structured jet.

  1. Analytical Aerodynamic Simulation Tools for Vertical Axis Wind Turbines

    International Nuclear Information System (INIS)

    Deglaire, Paul

    2010-01-01

    Wind power is a renewable energy source that is today the fastest growing solution to reduce CO 2 emissions in the electric energy mix. Upwind horizontal axis wind turbine with three blades has been the preferred technical choice for more than two decades. This horizontal axis concept is today widely leading the market. The current PhD thesis will cover an alternative type of wind turbine with straight blades and rotating along the vertical axis. A brief overview of the main differences between the horizontal and vertical axis concept has been made. However the main focus of this thesis is the aerodynamics of the wind turbine blades. Making aerodynamically efficient turbines starts with efficient blades. Making efficient blades requires a good understanding of the physical phenomena and effective simulations tools to model them. The specific aerodynamics for straight bladed vertical axis turbine flow are reviewed together with the standard aerodynamic simulations tools that have been used in the past by blade and rotor designer. A reasonably fast (regarding computer power) and accurate (regarding comparison with experimental results) simulation method was still lacking in the field prior to the current work. This thesis aims at designing such a method. Analytical methods can be used to model complex flow if the geometry is simple. Therefore, a conformal mapping method is derived to transform any set of section into a set of standard circles. Then analytical procedures are generalized to simulate moving multibody sections in the complex vertical flows and forces experienced by the blades. Finally the fast semi analytical aerodynamic algorithm boosted by fast multipole methods to handle high number of vortices is coupled with a simple structural model of the rotor to investigate potential aeroelastic instabilities. Together with these advanced simulation tools, a standard double multiple streamtube model has been developed and used to design several straight bladed

  2. Serotonin, tryptophan metabolism and the brain-gut-microbiome axis.

    Science.gov (United States)

    O'Mahony, S M; Clarke, G; Borre, Y E; Dinan, T G; Cryan, J F

    2015-01-15

    The brain-gut axis is a bidirectional communication system between the central nervous system and the gastrointestinal tract. Serotonin functions as a key neurotransmitter at both terminals of this network. Accumulating evidence points to a critical role for the gut microbiome in regulating normal functioning of this axis. In particular, it is becoming clear that the microbial influence on tryptophan metabolism and the serotonergic system may be an important node in such regulation. There is also substantial overlap between behaviours influenced by the gut microbiota and those which rely on intact serotonergic neurotransmission. The developing serotonergic system may be vulnerable to differential microbial colonisation patterns prior to the emergence of a stable adult-like gut microbiota. At the other extreme of life, the decreased diversity and stability of the gut microbiota may dictate serotonin-related health problems in the elderly. The mechanisms underpinning this crosstalk require further elaboration but may be related to the ability of the gut microbiota to control host tryptophan metabolism along the kynurenine pathway, thereby simultaneously reducing the fraction available for serotonin synthesis and increasing the production of neuroactive metabolites. The enzymes of this pathway are immune and stress-responsive, both systems which buttress the brain-gut axis. In addition, there are neural processes in the gastrointestinal tract which can be influenced by local alterations in serotonin concentrations with subsequent relay of signals along the scaffolding of the brain-gut axis to influence CNS neurotransmission. Therapeutic targeting of the gut microbiota might be a viable treatment strategy for serotonin-related brain-gut axis disorders. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. The manufacturing and metrology of off-axis mirrors

    Science.gov (United States)

    Penzkofer, Karlheinz; Rascher, Rolf; Küpper, Lutz; Liebl, Johannes

    2015-10-01

    Especially in the area of the large mirror manufacturing only a few manufacturers are capable to produce optical surfaces of high quality. Therefore a deterministic process should be developed in the project IFasO. In the field of telescope optics off-axis optical systems are becoming increasingly important. These systems try to avoid an obstructing of the incoming light by moving the secondary mirror out of the primary mirror's optical axis. This advantage leads to an increasing market for this type of optical surface. Until now off-axis mirrors were difficult or almost impossible to produce. With the processes developed in IFasO, high quality mirrors become possible. For this reason, this paper describes the manufacturing of off-axis surfaces and its problems. The mirror production used in the project IFasO is based on the specific design of the CNC center developed by the company Optotech. This center UPG2000 is capable of grinding, polishing, sagitta measurement and interferometric measurement in one mounting of the specimen. Usually a large optics has to be transported during their manufacturing after every individual process step. There is always a risk of damage of the specimen. The exact orientation of the surface relatively to the tool position is also required. This takes a huge amount of time and makes up most of the production time. In this presentation the use of UPG2000 and the next steps within the process development are described. In the current status the manufacturing of large off-axis elements with a PV < λ/10 rms is reproducible.

  4. Differences among doses for neuro-axis radiotherapy planning in the gonadal region

    International Nuclear Information System (INIS)

    Lima, F.F de; Vilela, E.C.; Oliveira, F.L.; Filho, J.A.

    2015-01-01

    Radiotherapy can disrupt the functioning of the hypothalamic-pituitary axis, directly causing ovarian deficiencies, such as the decrease in fertility or damage that renders the uterus incapable of accommodating the growth of a fetus. However, these issues have become increasingly important to a growing number of pediatric and adolescent cancer survivors. The whole-body, cranial-spinal axis, as well as abdomen and pelvic region irradiations may expose the ovaries to radiation and may cause premature ovarian failure, whereas doses above 35 Gy cranial can affect the hypothalamic-pituitary functions. This study performed a comparison of four doses of radiotherapy planning techniques for the neural axis. For this analysis, technical simulations were performed for the treatment of medulloblastoma in four different planning, applied in a RANDO anthropomorphic phantom and dosimeters (TLD-100). The radiation fields in the 1”st and 2”nd planning were 40 x 5 cm”2 and 17 x 5 cm”2 with 4.0 cm depth, in which doses were 0.03 and 0.05 Gy / day and 0.11 and 0.09 Gy / days, on the right and left sides, respectively. The 3”rd and 4”th measured planning 32 x 7 cm”2 and 18 x 7 cm”2, with a 2 cm gap and a 4.0 and 5.0 cm depth, in which doses were 1.08 and 0.2 Gy/day and 1.14 and 0.14 Gy/day, on the left and right sides, respectively. It could be observed that the doses in the ovaries in the 3”rd and 4”th schedules proved to be larger than the doses in the 1 s t and 2 n d planning. This is caused by the spinal field width and the depth of the second spinal field, which is 1.0 cm more than the field of the 1”st and 2”nd planning. These differences should be observed in image planning, as incorrect measures can cause damage in the treatment finish. (authors)

  5. Paediatric medulloblastoma: patterns of care and radiotherapy quality assurance in Australia

    International Nuclear Information System (INIS)

    Ahern, V.; Koh, E-S.; Gebski, V.; Sathiyaseelan, Y.

    2007-01-01

    Full text: The purpose of this study was to document how children in Australia with medulloblastoma are being treated and to evaluate the quality of radiotherapy (RT) delivered. The Radiotherapy Database of the Australian and New Zealand Children's Haematology and Oncology Group was used to identify 46 children with medulloblastoma younger than the age of 15 years treated with radical intent by craniospinal irradiation between 1997 and 1999 inclusively. Twenty-six patients had completely resected disease without evidence of disease spread. Of these, 16 patients received a craniospinal RT dose of <25 Gy in addition to chemotherapy. RT treatment immobilization methods varied, as did planning methods. RT dose to critical structures was recorded on treatment plans for only 15% of patients. The average systematic error in shield placement at the posterior orbit was 5.2 mm, and two-thirds of patients were 'overshielded' at this site. Adequate coverage of the distal end of the thecal sac was achieved in fewer than 50% of on-treatment verification films for 21 of 45 patients. With a reduction in RT dose to the craniospinal axis for paediatric medulloblastoma, greater attention is needed for patient immobilization, documentation of RT dose to critical structures and the placement and reproducibility of shielding

  6. Facts about food irradiation: Packaging of irradiated foods

    International Nuclear Information System (INIS)

    1991-01-01

    This fact sheet considers the effects on packaging materials of food irradiation. Extensive research has shown that almost all commonly used food packaging materials toted are suitable for use. Furthermore, many packaging materials are themselves routinely sterilized by irradiation before being used. 2 refs

  7. Facts about food irradiation: Irradiation and food safety

    International Nuclear Information System (INIS)

    1991-01-01

    This fact sheet focusses on the question of whether irradiation can be used to make spoiled food good. No food processing procedures can substitute for good hygienic practices, and good manufacturing practices must be followed in the preparation of food whether or not the food is intended for further processing by irradiation or any other means. 3 refs

  8. Food irradiation and sterilization

    International Nuclear Information System (INIS)

    Josephson, E.S.

    1981-01-01

    Radiation sterilization of food (radappertization) requires exposing food in sealed containers to ionizing radiation at absorbed doses high enough (25 to 70 kGy) to kill all organisms of food spoilage and public health significance. Radappertization is analogous to thermal canning in achieving shelf stability (long term storage without refrigeration). Except for dry products in which autolysis is negligible, the radappertization process also requires that the food be heated to an internal temperature of 70 to 80 0 C (bacon to 53 0 C) to inactivate autolytic enzymes which catalyze spoilage during storage without refrigeration. To minimize the occurrence of irradiation induced off-flavors and odors, undesirable color changes, and textural and nutritional losses from exposure to the high doses required for radappertization, the foods are vacuum sealed and irradiated frozen (-40 0 C to -20 0 C). Radappertized foods have the characteristic of fresh foods prepared for eating. Radappertization can substitute in whole or in part for some chemical food additives such as ethylene oxide and nitrites which are either toxic, carcinogenic, mutagenic, or teratogenic. After 27 years of testing for 'wholesomeness' (safety for consumption) of radappertized foods, no confirmed evidence has been obtained of any adverse effects of radappertization on the 'wholesomeness' characteristics of these foods. (author)

  9. Food irradiation and sterilization

    Science.gov (United States)

    Josephson, Edward S.

    Radiation sterilization of food (radappertization) requires exposing food in sealed containers to ionizing radiation at absorbed doses high enough (25-70 kGy) to kill all organisms of food spoilage and public health significance. Radappertization is analogous to thermal canning is achieving shelf stability (long term storage without refrigeration). Except for dry products in which autolysis is negligible, the radappertization process also requires that the food be heated to an internal temperature of 70-80°C (bacon to 53°C) to inactivate autolytic enzymes which catalyze spoilage during storage without refrigeration. To minimize the occurence of irradiation induced off-flavors and odors, undesirable color changes, and textural and nutritional losses from exposure to the high doses required for radappertization, the foods are vacuum sealed and irradiated frozen (-40°C to -20°C). Radappertozed foods have the characteristic of fresh foods prepared for eating. Radappertization can substitute in whole or in part for some chemical food additives such as ethylene oxide and nitrites which are either toxic, carcinogenic, mutagenic, or teratogenic. After 27 years of testing for "wholesomeness" (safety for consumption) of radappertized foods, no confirmed evidence has been obtained of any adverse effecys of radappertization on the "wholesomeness" characteristics of these foods.

  10. Generic phytosanitary irradiation treatments

    International Nuclear Information System (INIS)

    Hallman, Guy J.

    2012-01-01

    The history of the development of generic phytosanitary irradiation (PI) treatments is discussed beginning with its initial proposal in 1986. Generic PI treatments in use today are 150 Gy for all hosts of Tephritidae, 250 Gy for all arthropods on mango and papaya shipped from Australia to New Zealand, 300 Gy for all arthropods on mango shipped from Australia to Malaysia, 350 Gy for all arthropods on lychee shipped from Australia to New Zealand and 400 Gy for all hosts of insects other than pupae and adult Lepidoptera shipped to the United States. Efforts to develop additional generic PI treatments and reduce the dose for the 400 Gy treatment are ongoing with a broad based 5-year, 12-nation cooperative research project coordinated by the joint Food and Agricultural Organization/International Atomic Energy Agency Program on Nuclear Techniques in Food and Agriculture. Key groups identified for further development of generic PI treatments are Lepidoptera (eggs and larvae), mealybugs and scale insects. A dose of 250 Gy may suffice for these three groups plus others, such as thrips, weevils and whiteflies. - Highlights: ► The history of phytosanitary irradiation (PI) treatments is given. ► Generic PI treatments in use today are discussed. ► Suggestions for future research are presented. ► A dose of 250 Gy for most insects may suffice.

  11. Long-term field test of solar PV power generation using one-axis 3-position sun tracker

    KAUST Repository

    Huang, B.J.

    2011-09-01

    The 1 axis-3 position (1A-3P) sun tracking PV was built and tested to measure the daily and long-term power generation of the solar PV system. A comparative test using a fixed PV and a 1A-3P tracking PV was carried out with two identical stand-alone solar-powered LED lighting systems. The field test in the particular days shows that the 1A-3P tracking PV can generate 35.8% more electricity than the fixed PV in a partly-cloudy weather with daily-total solar irradiation HT=11.7MJ/m2day, or 35.6% in clear weather with HT=18.5MJ/m2day. This indicates that the present 1A-3P tracking PV can perform very close to a dual-axis continuous tracking PV (Kacira et al., 2004). The long-term outdoor test results have shown that the increase of daily power generation of 1A-3P tracking PV increases with increasing daily-total solar irradiation. The increase of monthly-total power generation for 1A-3P sun tracking PV is between 18.5-28.0%. The total power generation increase in the test period from March 1, 2010 to March 31, 2011, is 23.6% in Taipei (an area of low solar energy resource). The long-term performance of the present 1X-3P tracking PV is shown very close to the 1-axis continuous tracking PV in Taiwan (Chang, 2009). If the 1A-3P tracking PV is used in the area of high solar energy resource with yearly-average HT>17MJ/m2day, the increase of total long-term power generation with respect to fixed PV will be higher than 37.5%. This is very close to that of dual-axis continuous tracking PV. The 1A-3P tracker can be easily mounted on the wall of a building. The cost of the whole tracker is about the same as the regular mounting cost of a conventional rooftop PV system. This means that there is no extra cost for 1A-3P PV mounted on buildings. The 1A-3P PV is quite suitable for building-integrated applications. © 2011 Elsevier Ltd.

  12. Evaluation of the effect of Q-switched ruby and Q-switched Nd-YAG laser irradiation on melanosomes in dermal melanocytosis.

    Science.gov (United States)

    Ogata, H

    1997-12-01

    Q-switched ruby laser (QSRL) and Q-switched Nd-YAG laser (QSNYL) treatment of dermal melanocytosis, especially nevus of Ota, has produced favorable results that are mediated by selective photothermolysis. However, the precise effects of irradiation on melanosomes and cells containing melanosomes remain unclear, and an optimal method of irradiation has not been found. In this study synthetic melanin powder and pigmented dermal tissue obtained from five blue nevus lesions, also classified as dermal melanocytosis, were used as targets to identify the specific effects of these forms of irradiation in vitro. Morphological changes were assessed by microscopy after irradiation with QSRL and QSNYL at a fluence of 5 J/cm2, the fluence ordinarily utilized in clinical applications. Light microscopy revealed that most of the synthetic melanin powder retained in 1% agar was no longer visible after QSRL irradiation. In contrast, melanin powder particles were partly crushed by QSNYL irradiation. Electron microscopic examination of melanosomes in the blue nevus tissue after irradiation showed expansion and various other forms of disruption. Statistical analysis by 2-way analysis of variance (ANOVA) of the length of the major axis of the melanosomes indicated that QSRL irradiation caused significantly greater melanosome expansion than QSNYL irradiation. These findings indicate that QSRL irradiation had a greater photothermal effect on dermal melanosomes than QSNYL irradiation. This suggests that QSRL is more efficacious in the treatment of dermal melanocytosis than QSNYL.

  13. Storage tests with irradiated and non-irradiated onions

    International Nuclear Information System (INIS)

    Gruenewald, T.; Rumpf, G.; Troemel, I.; Bundesforschungsanstalt fuer Ernaehrung, Karlsruhe

    1978-07-01

    The results of several test series on the storage of irradiated and non-irradiated German grown onion are reported. Investigated was the influence of the irradiation conditions such as time and dose and of the storage conditions on sprouting, spoilage, browning of the vegetation centres, composition of the onions, strength and sensorial properties of seven different onion varieties. If the onions were irradiated during the dormancy period following harvest, a dose of 50 Gy (krad) was sufficient to prevent sprouting. Regarding the irradiated onions, it was not possible by variation of the storage conditions within the limits set by practical requirements to extend the dormancy period or to prevent browning of the vegetation centres, however. (orig.) 891 MG 892 RSW [de

  14. Irradiation hardening of pure tungsten exposed to neutron irradiation

    Science.gov (United States)

    Hu, Xunxiang; Koyanagi, Takaaki; Fukuda, Makoto; Kumar, N. A. P. Kiran; Snead, Lance L.; Wirth, Brian D.; Katoh, Yutai

    2016-11-01

    Pure tungsten samples have been neutron irradiated in HFIR at 90-850 °C to 0.03-2.2 dpa. A dispersed barrier hardening model informed by the available microstructure data has been used to predict the hardness. Comparison of the model predictions and the measured Vickers hardness reveals the dominant hardening contribution at various irradiation conditions. For tungsten samples irradiated in HFIR, the results indicate that voids and dislocation loops contributed to the hardness increase in the low dose region (0.6 dpa). The precipitate contribution is most pronounced for the HFIR irradiations, whereas the radiation-induced defect cluster microstructure can rationalize the entirety of the hardness increase observed in tungsten irradiated in the fast neutron spectrum of Joyo and the mixed neutron spectrum of JMTR.

  15. The wholesomeness of irradiated food

    International Nuclear Information System (INIS)

    Elias, P.S.

    1976-01-01

    The acceptance of food irradiation as a safe process of preservation by national authorities concerned with the safety of foodstuffs has hitherto made slow progress. The technology has existed for some 25 years but the general attitude towards official acceptance of the process has been marred by irrational and unscientific fears. As may have been mentioned by previous speakers,'the basic process of food irradiation does not differ in the physical sense from any other food processing techniques which involve the application of radiation energy to food. The energy level used in food irradiation is too low ever to lead to any production of radioactivity in the irradiated food, hence wholesomeness considerations can totally exclude this aspect. The uniqueness of food irradiation rests inherently on the particular type of energy employed and has aroused special attention because of this fact. The wholesomeness of food treated by heat or microwaves has not been questioned to the same extent, yet the very same question has been raised in relation to treatment by gamma rays and electron beams. Being a new process it requires not only a toxicological but also a microbiological as well as nutritional approach to the assessment of the wholesomeness of irradiated food. Studies on the radiation chemistry of proteins, lipids and carbohydrates, the main constituents of foods, when irradiated in the Mrad range, have yielded information which shows that these substances react in a reasonably uniform manner to irradiation. Many of the irradiation-induced compounds identified in irradiated foods can also be found in various non-irradiated foods. For those products that have been identified, the quantities found are in the parts per million range or less. Available data on the structures of radiation chemical products in food and the very low concentrations at which they occur, suggest the general conclusion that the health hazard they might represent is negligible

  16. Food irradiation development: Malaysian perspective

    International Nuclear Information System (INIS)

    Zainon Othman

    1997-01-01

    Malaysia recognised the potential of food irradiation as a technology that can contribute to solving some preservation problems associated with local agricultural produce. Research studies in this technology were initiated in late 1970s and since 1985, all activities pertaining to R and D applications, adoption and technology transfer of food irradiation were coordinated by The National Working Committee on Food Irradiation which comprises of members from research institutes, universities, regulatory agencies and consumer association. To date, technical feasibility studies conducted on 7 food items / agricultural commodities of economic importance demonstrated the efficacy of irradiation in extending shelf-life, improving hygienic quality and overcoming quarantine barriers in trade. Presently, 1 multipurpose Co-60 irradiator (I MCi), 2 gammacells and an electron beam machine (3 MeV) are available at MINT for research and commercial runs. The Malaysian Standards on Guidelines for Irradiation of Food was formulated in 1992 to facilitate application by local food industries. However, Malaysia has not yet commercially adopt the technology. Among many factors contributing to the situation is the apparent lack of interest by food industries and consumers. Consumer attitude study indicated majority of consumers are still unaware of the benefits of the technology and expressed concern for the safety of process and irradiated products due to limited knowledge and adverse publicity by established consumer groups. Although the food processors indicate positive attitude towards food irradiation, there remain many factors delaying its commercial application such as limited knowledge, cost-benefit, logistics and consumer acceptance. On the regulatory aspect, approval is required from the Director-General of Ministry of Health prior to application of irradiation on food and sale of irradiated food but efforts are being geared towards approving irradiation of certain food

  17. Consumer acceptance of irradiated poultry

    International Nuclear Information System (INIS)

    Hashim, I.B.; Resurreccion, A.V.A.; McWatters, K.H.

    1995-01-01

    A simulated supermarket setting (SSS) test was conducted to determine whether consumers (n = 126) would purchase irradiated poultry products, and the effects of marketing strategies on consumer purchase of irradiated poultry products. Consumer preference for irradiated poultry was likewise determined using a home-use test. A slide program was the most effective educational strategy in changing consumers' purchase behavior. The number of participants who purchased irradiated boneless, skinless breasts and irradiated thighs after the educational program increased significantly from 59.5 and 61.9% to 83.3 and 85.7% for the breasts and thighs, respectively. Using a label or poster did not increase the number of participants who bought irradiated poultry products. About 84% of the participants consider it either 'somewhat necessary' or 'very necessary' to irradiate raw chicken and would like all chicken that was served in restaurants or fast food places to be irradiated. Fifty-eight percent of the participants would always buy irradiated chicken if available, and an additional 27% would buy it sometimes. About 44% of the participants were willing to pay the same price for irradiated chicken as for nonirradiated. About 42% of participants were willing to pay 5% or more than what they were currently paying for nonirradiated chicken. Seventy-three percent or more of consumers who participated in the home-use test (n = 74) gave the color, appearance, and aroma of the raw poultry products a minimum rating of 7 (= like moderately). After consumers participated in a home-use test, 84 and 88% selected irradiated thighs and breasts, respectively, over nonirradiated in a second SSS test

  18. Sensorial evaluation of irradiated mangoes

    International Nuclear Information System (INIS)

    Broisler, Paula Olhe; Cruz, Juliana Nunes da; Sabato, Susy Frey

    2007-01-01

    Mango (Mangifera indica L.) is a tropical fruit of great economical relevance in the world, mainly for tropical countries like Brazil. It consists in the second tropical fruit more important grown in the world. On the other hand it is a very perishable fruit and its delivery to distant points is restricted due to short shelf life at environmental temperature. Food irradiation process is applied to fruits for their preservation, once it promotes disinfestation and even maturation retard, among other mechanisms. The Brazilian legislation permits the food irradiation and does not restrict the doses to be delivered. In order to verify eventual changes, sensorial evaluation is very important to study how irradiation affects the quality of the fruit and its acceptability. Mangoes were irradiated in a Cobalto-60 source, from the Radiation Technology Center, CTR, of IPEN/CNEN-SP at doses 0,5 kGy e 0,75 kGy. The sensorial evaluation was measured through Acceptance Test where irradiated samples were offered together with control sample to the tasters who answered their perception through hedonic scale. The parameters Color, Odor, Flavor and Texture were analyzed. Statistical analysis showed that only Odor parameter was different from control (sample irradiated at 0.5 kGy). Few tasters indicated that irradiated mangoes had fewer odors in relation to non-irradiated samples. (author)

  19. Food irradiation: contaminating our food

    International Nuclear Information System (INIS)

    Piccioni, R.

    1988-01-01

    The nuclear industry has promoted food irradiation as an effective and safe means of preserving food at minimum risk to the public. However, wide-scale food irradiation programmes such as that approved in the United States of America would have an adverse impact on public health in the following ways: through the consumption of carcinogenic substances generated in irradiated foods, through the use of irradiation to mask bacteriological contamination of spoiled food, through the replacement of fresh foods with nutritionally depleted foods, through accidents with leaks or mishandling of the radiation sources used and through the environmental damage resulting from reactor operation or spent fuel reprocessing necessary to produce the required isotopes for food irradiation. The food irradiation market is potentially enormous, requiring a large number of facilities and isotopes, some, such as caesium-137, would come from the production of nuclear weapons. Evidence of the presence of carcinogenic or mutagenic activity in irradiated foods is discussed. Although the US Federal Drug Administration (FDA) has approved a food irradiation programme it would actually be against the FDA's legal obligation which is to protect the health and safety of the American people. (UK)

  20. Nutritional aspects of irradiated shrimp

    International Nuclear Information System (INIS)

    Shamsuzzaman, K.

    1989-11-01

    Data available in the literature on the nutritional aspects of irradiated shrimp are reviewed and the indication is that irradiation of shrimp at doses up to about 3.2 kGy does not significantly affect the levels of its protein, fat, carbohydrate and ash. There are no reports on the effect of irradiation of shrimp above 3.2 kGy on these components. Limited information available indicates that there are some minor changes in the fatty acid composition of shrimp as a result of irradiation. Irradiation also causes some changes in the amino acid composition of shrimp; similar changes occur due to canning and hot-air drying. Some of the vitamins in shrimp, such as thiamine, are lost as a result of irradiation but the loss is less extensive than in thermally processed shrimp. Protein quality of shrimp, based on the growth of rats as well as that of Tetrahymena pyriformis, is not affected by irradiation. No adverse effects attributed to irradiation were found either in short-term or long-term animal feeding tests

  1. An overview of food irradiation

    International Nuclear Information System (INIS)

    Stevenson, M.H.

    1991-01-01

    This outline survey reviews the subject of food irradiation under the following headings:- brief history, the process (sources, main features of a food processing facility, interaction of radiation with food, main applications of the technology, packaging) consumer concerns (safety, nutritional changes, labelling, detection), international use of food irradiation and legal aspects. (UK)

  2. ASEAN workshop on food irradiation

    International Nuclear Information System (INIS)

    1985-01-01

    This proceedings was organized by the ASEAN Food Handling Bureau in Collaboration with the Thai Atomic Energy Commission for Peace. Experts from ASEAN and overseas were invited to present a series of papers covering the state of the art of irradiation technology and the important issues relating to food irradiation

  3. Optical absorption of irradiated carbohydrates

    International Nuclear Information System (INIS)

    Supe, A.A.; Tiliks, Yu.E.

    1994-01-01

    The optical absorption spectra of γ-irradiated carbohydrates (glucose, lactose, sucrose, maltose, and starch) and their aqueous solutions were studied. The comparison of the data obtained with the determination of the concentrations of molecular and radical products of radiolysis allows the absorption bands with maxima at 250 and 310 nm to be assigned to the radicals trapped in the irradiated carbohydrates

  4. National symposium on food irradiation

    International Nuclear Information System (INIS)

    Beyers, M.; Brodrick, H.T.; Van Niekerk, W.C.A.

    1980-01-01

    This report contains proceedings of papers delivered at the national symposium on food irradiation held in Pretoria. The proceedings have been grouped into the following sections: general background; meat; agricultural products; marketing; and radiation facilities - cost and plant design. Each paper has been submitted separately to INIS. Tables listing irradiated food products cleared for human consumption in different countries are given

  5. World trend of food irradiation

    International Nuclear Information System (INIS)

    Kooij, J.G. van

    1984-01-01

    Over the past fifteen years several policies and programmes have been developed in the field of food irradiation at the national level and by international organizations concerned, which aim at the general acceptance and practical implementation of food irradiation through rigorous investigations of the wholesomeness, the technological and economic feasibility, and the regulatory aspects of this process. This paper reivews international aspects of the standardization of food irradiation, national regulatory aspects of food irradiation, general remarks on the acceptance of Codex General Standards for irradiated foods, and specific remarks on the Codex General Standard for irradiated foods. An overall average dose for all foods, which was formulated in 1980 by a Joint FAO/IAEA/WHO Expert Committee, is 10 kGy. This 10 kGy is not a level above which irradiated foods become unsafe, rather, it is a level at or below which safety has been established. Irradiation dose is divided into low-dose (up to about 1 kGy) and medium-dose (about 1-10 kGy). Future outlook and needs are discussed. (Namekawa, K.)

  6. Consumer attitude toward food irradiation

    International Nuclear Information System (INIS)

    Bruhn, C.M.M.

    1986-01-01

    Consumer attitudes toward food irradiation were evaluated. The influence of educational efforts on consumer concern for the safety of irradiated products and willingness to buy irradiated foods were measured. Demographic and psychological factors were studied in relation to attitudes. An educational leaflet describing current scientific information regarding the safety, advantages, and disadvantages of food irradiation was developed and used in two studies evaluating attitude change. In the first study, attitude change among two groups of consumers with different philosophic orientations was measured. In a second study, the effectiveness of an educational leaflet received through the mail and a poster display were examined. In a third study response to food irradiation was related to value hierarchy, locus of control, innovativeness, and demographic parameters. Initially, subjects showed a higher concern for other areas of food safety, particularly the use of chemicals and sprays on food, than toward food irradiation. After educational efforts, conventional consumers expressed minor concern toward irradiation whereas ecologically sensitive alternative consumers obtained from a food cooperative expressed major concern. A knowledgeable discussion leader lowered irradiation concern among conventional consumers. In contrast, concern among alternative consumers did not diminish when given the opportunity to discuss safety issues with a knowledgeable person

  7. Food irradiation seminar: Asia and the Pacific

    International Nuclear Information System (INIS)

    Mitchell, G.E.

    1986-01-01

    The report covers the Seminar for Asia and the Pacific on the practical application of food irradiation. The seminar assessed the practical application of food irradiation processes, commercial utilisation and international trade of irradiated food

  8. Food irradiation: advantages and limitations

    International Nuclear Information System (INIS)

    Hernandes, N.K.; Vital, H. de C.; Sabaa-Srur, A.U.O.

    2003-01-01

    Food irradiation is a physical method of processing food (e.g. freezing, canning). It has been thoroughly researched over the last four decades and is recognized as a safe and wholesome method. It has the potential both of disinfesting dried food to reduce storage losses and disinfesting fruits and vegetables to meet quarantine requirements for export trade. Low doses of irradiation inhibit spoilage losses due to sprouting of root and tuber crops. Food- borne diseases due to contamination by pathogenic microorganisms and parasites of meat, poultry, fish, fishery products and spices are on the increase. Irradiation of these solid foods can decontaminate them of pathogenic organisms and thus provide safe food to the consumer. Irradiation can successfully replace the fumigation treatment of cocoa beans and coffee beans and disinfest dried fish, dates, dried fruits, etc. One of the most important advantages of food irradiation processing is that it is a coldprocess which does not significantly alter physico-chemical characters of the treated product. It can be applied to food after its final packaging. Similar to other physical processes of food processing, (e.g. canning, freezing), irradiation is a capital intensive process. Thus, adequate product volume must be made available in order to maximize the use of the facility and minimize the unit cost of treatment. Lack of harmonization of regulations among the countries which have approved irradiated foods hampers the introduction of this technique for international trade. Action at the international level has to be taken in order to remedy this situation. One of the important limitations of food irradiation processing is its slow acceptance by consumers, due inter alia to a perceived association with radioactivity. The food industry tends to be reluctant to use the technology in view of uncertainties regarding consumer acceptance of treated foods. Several market testing and consumer acceptance studies have been carried

  9. Dosimetry of blood irradiator - 2000

    International Nuclear Information System (INIS)

    Mhatre, Sachin G.V.; Shinde, S.H.; Bhat, R.M.; Rao, Suresh; Sharma, D.N.

    2008-01-01

    Full text: Blood transfusion to an immunodeficient or immunosuppressed patient has a high risk involved due to occurrence of Transfusion Graft Versus Host Disease (T-GVHD). In order to eliminate this problem, blood is routinely exposed to ionizing radiation (gamma) prior to transfusion. Doses ranging from 15 Gy to 50 Gy can prevent T-GVHD. Aim of the present work was to perform dosimetry of 60 Co Blood Irradiator-2000 developed by Board of Radiation and isotope Technology (BRIT), India; using FBX dosimetric system. Dose-rate measured by FBX dosimeter was intercompared with Fricke dosimeter, which is a Reference Standard dosimeter. Experiments included measurement of dose-rate at the centre of irradiation volume, dose mapping in the central vertical plane within the irradiation volume and measurement of average dose received by blood sample using blood bags filled with FBX dosimeter by simulating actual irradiation conditions. During irradiation, the sample chamber is retracted into a cylindrical source cage, so that the sample is irradiated from all sides uniformly. Blood irradiator-2000 has sample rotation facility for increasing the dose uniformity during irradiation. The performance of this was investigated by measuring the central vertical plane dose profile in stationary state as well in rotation using the sample rotation facility (60 rpm). FBX being an aqueous dosimetric system fills container of irregular shape being irradiated hence can be used to integrate the dose over the volume. Dose-rate measured by FBX dosimeter was intercompared with Fricke dosimeter, which was in good agreement. Average dose-rate at the centre of irradiation volume and within the blood bag was measured by FBX and Fricke dosimeters. It was observed that dose profiles measured by FBX and Fricke dosimeters agreed within ± 2%. Dose uniformity within the irradiation volume was found to reduce from 21% to 17% when the sample rotation facility was used. Thus, it is suggested by the

  10. Commercial implementation of food irradiation

    Science.gov (United States)

    Welt, M. A.

    In July 1981, the first specifically designed multi-purpose irradiation facility for food irradiation was put into service by the Radiation Technology, Inc. subsidiary Process Technology, Inc. in West Memphis, Arkansas. The operational experience gained, resulted in an enhanced design which was put into commercial service in Haw River, North Carolina, by another subsidiary, Process Technology (N.C.), Inc. in October 1983. These facilities have enabled the food industry to assess the commercial viability of food irradiation. Further impetus towards commercialization of food irradiation was gained in March 1981 with the filing in the Federal Register, by the FDA, of an Advanced Proposed Notice of Rulemaking for Food Irradiation. Two years later in July 1983, the FDA approved the first food additive regulation involving food irradiation in nineteen years, when they approved the Radiation Technology, Inc. petition calling for the sanitization of spices, onion powder and garlic powder at a maximum dosage of 10 kGy. Since obtaining the spice irradiation approval, the FDA has accepted four additional petitions for filing in the Federal Register. One of the petitions which extended spice irradiation to include insect disinfestation has issued into a regulation while the remaining petitions covering the sanitization of herbs, spice blends, vegetable seasonings and dry powdery enzymes as well as the petition to irradiate hog carcasses and pork products for trichinae control at 1 kGy, are expected to issue either before the end of 1984 or early in 1985. More recently, food irradiation advocates in the United States received another vote of confidence by the announcement that a joint venture food irradiation facility to be constructed in Hawaii by Radiation Technology, is backed by a contractual committment for the processing of 40 million pounds of produce per year. Another step was taken when the Port of Salem, New Jersey announced that the Radiation Technology Model RT-4104

  11. Extraction of left-ventricular torsion angle from the long-axis view by block-matching algorithm: Comparison with the short-axis view.

    Science.gov (United States)

    Arab-Baferani, Zahra; Mokhtari-Dizaji, Manijhe; Roshanali, Farideh

    2013-02-01

    Due to limitations in measuring the torsion angle in the short-axis view when studying through-plane motion and so it is dependent on reference levels, in this study, we follow myocardial movement along the long-axis of the left ventricle (LV). Then, LV torsion is estimated in the long-axis view and compared with LV torsion in the short-axis view. Two dimensional echocardiographic images of healthy persons were recorded in cine loop format position throughout four cardiac cycles at basal and apical levels in the long- and short-axis views. The motion vectors for reign of interest in the horizontal and vertical directions were obtained by block matching algorithm. Correlation between the values of automated analysis and manual tracing was performed by Pearson correlation analysis. Then, the maximum rotation angles of the short- and long-axis views at basal and apical levels were assessed. Left-ventricular torsion angles in short-axis and long-axis views were calculated and compared based on rotation angles. There was a high correlation between the measured myocardial wall displacement of automated analysis (BM algorithm) and manual tracing (R=0.96, p<0.05). The maximum rotation angles of basal and apical levels in the short-axis view are 7.96±1.57° and 9.49±1.72° and so in the long-axis view are 18.51±3.41° and 14.74±2.91°, respectively. The LV torsion angles and the time to reach peak LV torsion angles in the short-axis views are 17.26±2.53°, 293±26ms and in the long-axis view are 32.26±5.60° and 290±22ms respectively. There was a high correlation between the left-ventricular torsion angle in the short-axis view and the long-axis view (R=0.92, p<0.05). There was also a high correlation between the time to reach peak left-ventricular torsion angle in the short-axis view as compared to the long-axis view (R=0.97, p<0.05). This study suggested that the LVtorsion angles in the short- and long-axis views were significantly correlated. It is concluded that

  12. Food irradiation: the 'experts' choice

    International Nuclear Information System (INIS)

    Watts, P.

    1990-01-01

    The UK Government has decided to lift the ban on food irradiation. The proponents of food irradiation claim it is an effective and safe means of preserving food, at minimum risk to the public. However, the prospect of irradiated food being on the shelves has created considerable opposition from environmental, consumer, public health groups and trade unions. The long list of unanswered health and safety questions means the public could be exposed to a whole new range of risks. The consumer is justified as saying ''if food has to be irradiated, what was wrong with it, good food does not need irradiating''. The answer to food contamination is improved hygiene and training in farm, factory and shop. (author)

  13. Consumer acceptance of irradiated food

    Energy Technology Data Exchange (ETDEWEB)

    Loaharanu, P. [Head, Food Preservation Section, Joint FAO/ IAEA Division of Nuclear Techniques in Food and Agriculture, Wagramerstr. 5, A-1400, Vienna (Austria)

    1997-12-31

    There was a widely held opinion during the 1970`s and 1980`s that consumers would be reluctant to purchase irradiated food, as it was perceived that consumers would confuse irradiated food with food contaminated by radionuclides. Indeed, a number of consumer attitude surveys conducted in several western countries during these two decades demonstrated that the concerns of consumers on irradiated food varied from very concerned to seriously concerned.This paper attempts to review parameters conducting in measuring consumer acceptance of irradiated food during the past three decades and to project the trends on this subject. It is believed that important lessons learned from past studies will guide further efforts to market irradiated food with wide consumer acceptance in the future. (Author)

  14. Irradiation history of meteoritic inclusions

    DEFF Research Database (Denmark)

    Wielandt, Daniel Kim Peel

    be coproduced at approximately the value found in CAIs. The required fluence levels can be reached in as little as half a year of particle irradiation at protosolar analog flux levels. We thus conclude that local charged particle irradiation played a significant if not dominating role in forming the 10Be and 41...... and local particle irradiation. If local particle irradiation was powerful, it may have left telltale signs in meteoritic inclusions that can constrain the conditions under which they were formed or stored prior to the formation of chondrites. The underlying research effort relates to answering the larger...... in the early solar system. We demonstrate novel techniques for measuring the isotopic composition of K, and show how such measurements can be related to the irradiation histories of meteoritic materials. We also show how potassium isotope measurement can complement measurements of 10Be, a proven spallogenic...

  15. Irradiation of spices - a review

    International Nuclear Information System (INIS)

    Sadecka, J.

    2007-01-01

    Food irradiation is a process of exposing food to ionising radiation such as gamma rays emitted from the radioisotopes 60Co and 137Cs, or high energy electrons and X-rays produced by machine sources. The use of ionising radiation to destroy harmful biological organisms in food is considered a safe, well proven process that has found many applications. Depending on the absorbed dose of radiation, various effects can be achieved resulting in reduced storage losses, extended shelf life and/or improved microbiological and parasitological safety of foods. The most common irradiated commercial products are spices and vegetable seasonings. Spice irradiation is increasingly recognised as a method that reduces post-harvest losses, ensures hygienic quality, and facilitates trade with food products. This article reviews recent activities concerning food irradiation, focusing on the irradiation of spices and dried vegetable seasonings from the food safety aspect

  16. Eatability of the irradiated food

    International Nuclear Information System (INIS)

    Luna C, P.C.

    1992-05-01

    A food is eatable and innocuous when it has an acceptable nutritional quality, it is toxicological and microbiologically safe for the human consumption. Not one preservation treatment allows to assure this in absolute form. As it happens with other conservation methods, the irradiation produce biological, chemical and physical changes in the treated food. For to check if such changes could cause damages to the health of the consumer, its have been carried out extensive studies to evaluate the inoculate of the irradiated foods. Analyzing diverse toxicity studies to prove the eatability of the irradiated foods, in this work those are presented but important in chronological order. In summary, until today it exists a great heap of tests that they demonstrate without place to doubts that the foods irradiated with a dose up to 10 KGy its are capable for the human consumption, for what can to be concluded that a safety margin exists to consume foods irradiated. (Author)

  17. Consumer acceptance of irradiated food

    International Nuclear Information System (INIS)

    Loaharanu, P.

    1997-01-01

    There was a widely held opinion during the 1970's and 1980's that consumers would be reluctant to purchase irradiated food, as it was perceived that consumers would confuse irradiated food with food contaminated by radionuclides. Indeed, a number of consumer attitude surveys conducted in several western countries during these two decades demonstrated that the concerns of consumers on irradiated food varied from very concerned to seriously concerned.This paper attempts to review parameters conducting in measuring consumer acceptance of irradiated food during the past three decades and to project the trends on this subject. It is believed that important lessons learned from past studies will guide further efforts to market irradiated food with wide consumer acceptance in the future. (Author)

  18. Pallet irradiators for food processing

    International Nuclear Information System (INIS)

    McKinnon, R.G.; Chu, R.D.H.

    1985-01-01

    This paper looks at the various design concepts for the irradiation processing of food products, with particular emphasis on handling the products on pallets. Pallets appear to offer the most attractive method for handling foods from many considerations. Products are transported on pallets. Warehouse space is commonly designed for pallet storage and, if products are already palletized before and after irradiation, then labour could be saved by irradiating on pallets. This is also an advantage for equipment operation since a larger carrier volume means lower operation speeds. Different pallet irradiator design concepts are examined and their suitability for several applications are discussed. For example, low product holdup for fast turn around will be a consideration for those operating an irradiation 'service' business; others may require a very large source where efficiency is the primary requirement and this will not be consistent with low holdup. The radiation performance characteristics and processing costs of these machines are discussed. (author)

  19. Irradiation of fresh fish

    Science.gov (United States)

    Yueh-jen, Yen; Jin-lai, Zhou; Shao-chun, Lai

    Occasionally, in China, marine products can not be provided for the markets in good quality, for during the time when they are being transported from the sea port to inland towns or even at the time when they are unloaded from the ship, they are beginning to spoil. Obviously, it is very important that appropiate measures should be taken to prevent them from decay. Our study has proved that the shelf life of fresh Flatfish (Cynoglossue robustus) and Silvery pomfret (stromateoides argenteus), which, packed in sealed containers, are irradiated by 1.5 kGy, 2.2 kGy and 3.0 kGy, can be stored for about 13-26 days at 3° - 5° C.

  20. Solute segregation during irradiation

    International Nuclear Information System (INIS)

    Wiedersich, H.; Okamoto, P.R.; Lam, N.Q.

    1977-01-01

    Irradiation at elevated temperature induces redistribution of the elements in alloys on a microstructural level. This phenomenon is caused by differences in the coupling of the various alloy constituents to the radiation-induced defect fluxes. A simple model of the segregation process based on coupled reaction-rate and diffusion equations is discussed. The model gives a good description of the experimentally observed consequences of radiation-induced segregation, including enrichment or depletion of solute elements near defect sinks such as surfaces, voids and dislocations; precipitation of second phases in solid solutions; precipitate redistribution in two-phase alloys; and effects of defect-production rates on void-swelling rates in alloys with minor solute additions

  1. Container for irradiated fuel

    International Nuclear Information System (INIS)

    Guy, R.

    1978-01-01

    The transport container for irradiated or used nuclear fuel is provided with an identical heat shield against fires on the top and bottom sides. Each heat shield consists of two inner nickel plates, whose contact surfaces are polished to a mirror finish and an outer plate of stainless steel. The nickel plate on the box is spot welded to it while the second nickel plate is spot welded to the steel plate. Both together are in turn welded so as to be leaktight to the edges of the box. For extreme heat effects and based on the different (bimetal) coefficients of expansion, the steel plate with the nickel plate attached to it bulges away from the box. The second nickel plate remains at the box, so that a subpressure space is formed with the mirror nickel surfaces. The heat radiation and heat conduction to the box are greatly reduced by this. (DG) [de

  2. Two-Axis Solar Heat Collection Tracker System for Solar Thermal Applications

    Directory of Open Access Journals (Sweden)

    Tsung-Chieh Cheng

    2013-01-01

    Full Text Available An experimental study was performed to investigate the effect of using a continuous operation two-axes tracking on the solar heat energy collected. This heat-collection sun tracking which LDR (light dependent resistor sensors installed on the Fersnel lens was used to control the tracking path of the sun with programming method of control with a closed loop system. The control hardware was connected to a computer through Zigbee wireless module and it also can monitor the whole tracking process information on a computer screen. An experimental study was performed to investigate the effect of using two-axes tracking on the solar heat energy collected. The results indicate that sun tracking systems are being increasingly employed to enhance the efficiency of heat collection by polar-axis tracking of the sun. Besides, the heating power was also measured by designed power measurement module at the different focal length of Fresnel lens, and the design of shadow mask of LDR sensors is an important factor for solar photothermal applications. Moreover, the results also indicated that the best time to obtain the largest solar irradiation power is during 11:00 –13:00  in Taiwan.

  3. Development of the adrenal axis in the neonatal rat

    Energy Technology Data Exchange (ETDEWEB)

    Guillet, Ronnie [Univ. of Rochester, NY (United States)

    1977-01-01

    Plasma corticosterone and ACTH concentrations were determined in neonatal rats 1, 7, 14, and 21 days old, under a variety of experimental conditions, to obtain more information on the postnatal development of the rat hypothalamo-adrenal (HHA) axis. The results indicate that: (1) there is a diminution followed by an increase in responsiveness of the adrenal gland, but the pituitary response to direct hormonal stimulation is unchanged during the first three postnatal weeks; (2) continued stimulation of the adrenal by ACTH or of the central nervous system (CNS) or hypothalamus by corticosterone is necessary during early postnatal development to allow normal maturation of the HHA axis; and (3) feedback inhibition is operative by birth, at least to a moderate degree. Taken together, the studies suggest that both the adrenal and pituitary glands are potentially functional at birth, but that the hypothalamic and CNS mediators of the stress response are not mature until at least the second or third postnatal week. (ERB)

  4. The on axis coupled structure type RF gun

    CERN Document Server

    Oda, F; Nakayama, A; Tanabe, E

    1999-01-01

    The fundamental design of this newly developed RF gun with a thermionic cathode is the pi/2 mode standing wave structure. It has two accelerating cells and a coupling cell located on the beam axis, a so-called on axis coupled structure (OCS). This structure offers a stable operation for high beam current, owing to high group velocity and wide bandwidth. It is important to reduce damage onto the cathode caused by back bombardment, especially for long macropulse operation, such as in an FEL injector. Back bombardment, as well as output beam profile was simulated by using the electromagnetic field analytical codes 'EMSYS'(2D) and 'MAFIA'(3D). The cavity shape was optimized to reduce back bombardment power without sacrificing beam emittance.

  5. APS-U LATTICE DESIGN FOR OFF-AXIS ACCUMULATION

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Yipeng; Borland, M.; Lindberg, R.; Sajaev, V.

    2017-06-25

    A 67-pm hybrid-seven-bend achromat (H7BA) lattice is being proposed for a future Advanced Photon Source (APS) multi-bend-achromat (MBA) upgrade project. This lattice design pushes for smaller emittance and requires use of a swap-out (on-axis) injection scheme due to limited dynamic acceptance. Alternate lattice design work has also been performed for the APS upgrade to achieve better beam dynamics performance than the nominal APS MBA lattice, in order to allow off-axis accumulation. Two such alternate H7BA lattice designs, which target a still-low emittance of 90 pm, are discussed in detail in this paper. Although the single-particle-dynamics performance is good, simulations of collective effects indicate that surprising difficulty would be expected accumulating high single-bunch charge in this lattice. The brightness of the 90-pm lattice is also a factor of two lower than the 67-pm H7BA lattice.

  6. Three-axis neutron spectrometer on the IWW-2 reactor

    International Nuclear Information System (INIS)

    Bobrovskij, V.I.; Goshchitskij, B.N.; Mirmel'shtejn, A.V.; Mikha lov, Yu.N.; Ponosov, Yu.S.

    1977-01-01

    A three-axis neutron spectrometer providing for the possibility to change smoothly the neutron scattering angle in the course of measurement was manufactured for studying the dynamics (frequencies and life time of phonons) of a crystalline lattice. This permits to use methods of constant energy and momentum transfer at fixed incident wave length in the scattering angle range of up to 100 deg. Major attention was given to such a substantial characteristic of the three-axis spectrometer as the spectrometer resolution function, which was determined experimentally and theoretically. A knowledge of that function permitted to make a sufficiently exact account of focusing effects when measuring neutron resonance, and to determine the instrumental widths of the resonances observed. A crystal incorporating a helium and nitrogen vessel was made for measurements in the 300-20 K range. A system of protective copper shields surrounding the helium vessel and a sample permits to operate without refilling helium for about 30 hr

  7. Psychiatric Axis I Comorbidities among Patients with Gender Dysphoria

    Directory of Open Access Journals (Sweden)

    Azadeh Mazaheri Meybodi

    2014-01-01

    Full Text Available Objectives. Cooccurring psychiatric disorders influence the outcome and prognosis of gender dysphoria. The aim of this study is to assess psychiatric comorbidities in a group of patients. Methods. Eighty-three patients requesting sex reassignment surgery (SRS were recruited and assessed through the Persian Structured Clinical Interview for DSM-IV Axis I disorders (SCID-I. Results. Fifty-seven (62.7% patients had at least one psychiatric comorbidity. Major depressive disorder (33.7%, specific phobia (20.5%, and adjustment disorder (15.7% were the three most prevalent disorders. Conclusion. Consistent with most earlier researches, the majority of patients with gender dysphoria had psychiatric Axis I comorbidity.

  8. Application of one-axis sun tracking system

    International Nuclear Information System (INIS)

    Sefa, Ibrahim; Demirtas, Mehmet; Colak, Ilhami

    2009-01-01

    This paper introduces design and application of a novel one-axis sun tracking system which follows the position of the sun and allows investigating effects of one-axis tracking system on the solar energy in Turkey. The tracking system includes a serial communication interface based on RS 485 to monitor whole processes on a computer screen and to plot data as graphic. In addition, system parameters such as the current, the voltage and the panel position have been observed by means of a microcontroller. The energy collected is measured and compared with a fixed solar system for the same solar panel. The results show that the solar energy collected on the tracking system is considerably much efficient than the fixed system. The tracking system developed in this study provides easy installation, simple mechanism and less maintenance.

  9. Effects of structure flexibility on horizontal axis wind turbine performances

    Science.gov (United States)

    Coiro, D. P.; Daniele, E.; Scherillo, F.

    2013-10-01

    This work illustrates the effects of flexibility of rotor blades and turbine tower on the performances of an horizontal axis wind turbine (HAWT) designed by our ADAG research group, by means of several example applied on a recent project for a active pitch controlled upwind 60 kW HAWT. The influence of structural flexibility for blade only, tower only and blade coupled with tower configuration is investigated using an aero-elastic computer-aided engineering (CAE) tool for horizontal axis wind turbines named FAST developed at National Renewable Energy Laboratory (NREL) of USA. For unsteady inflow conditions in front of the isolated HAWT the performances in rigid and flexible operation mode are computed and compared in order to illustrate the limitation included within a classical rigid body approach to wind turbine simulation.

  10. Spin squeezing in a generalized one-axis twisting model

    Science.gov (United States)

    Jin, Guang-Ri; Liu, Yong-Chun; Liu, Wu-Ming

    2009-07-01

    We investigate the dependence of spin squeezing on the polar angle of the initial coherent spin state |θ0, phi0rang in a generalized one-axis twisting model, where the detuning δ is taken into account. We show explicitly that regardless of δ and phi0, previous results of the ideal one-axis twisting are recovered as long as θ0=π/2. For a small departure of θ0 from π/2, however, the achievable variance (V -)min ~N2/3, which is larger than the ideal case N1/3. We also find that the maximal squeezing time tmin scales as N-5/6. Analytic expressions of (V-)min and tmin are presented and they agree with numerical simulations.

  11. Development of a Single-Axis Edge Detection System

    Energy Technology Data Exchange (ETDEWEB)

    Hanshaw, R.A.

    2000-02-18

    A SIP (Societe Genevoise d'Instruments de Physique) Trioptic coordinate measuring machine was modified for calibration of high quality single-axis glass standards to an uncertainty of {+-}0.000020 inch. The modification was accomplished through the addition of a frame grabber board, vision software, a high-resolution camera, stepper motors, a two-axis motor controller, and an HP-IB interface card. An existing temperature system (hygrometer, barometer, laser interferometer system, and optics) was retained as part of the system. An existing Hewlett Packard computer was replaced with a personal computer to accommodate the frame grabber board. Each component was integrated into the existing system using Visual Basic. The system was automated for unattended measurements by creating a machine programming language, which is recognized within the main program.

  12. Development of triple axis neutron spectrometer (Paper No. 24)

    International Nuclear Information System (INIS)

    Pal, B.C.; Wadhwa, N.R.; Goveas, S.H.

    1987-02-01

    The triple axis neutron spectrometers are the basic instruments intended for use with neutron beams from reactors. Various types of spectrometers, each devoted to different kinds of measurement can be designed and manufactured, once a prototype having all the attributes of a versatile instrument is designed and developed. With the view to achieving self reliance in this field, Central Workshops of Bhabha Atomic Research Centre (BARC), Bombay designed and developed a prototype of triple axis spectrometer meeting the specifications prepared by Nuclear Physics Division of BARC . This spectrometer, with a moving wedge system was successfully manufactured and installed at 'DHRUVA'. Another version of this spectrometer, called the 'Polarised Neutron Spectrometer' was also built and exported to South Korea and installed at Korea Advanced Energy Research Institute, Seoul. This paper deals with basic concept, development of design, engineering of mechanical assemblies, the manufacturing approach and problems encountered during manufacture. (author). 3 figs

  13. Efficiency of the DOMUS 750 vertical-axis wind turbine

    Science.gov (United States)

    Hallock, Kyle; Rasch, Tyler; Ju, Guoqiang; Alonso-Marroquin, Fernando

    2017-06-01

    The aim of this paper is to present some preliminary results on the efficiency of a wind turbine for an off-grid housing unit. To generate power, the unit uses a photovoltaic solar array and a vertical-axis wind turbine (VAWT). The existing VAWT was analysed to improve efficiency and increase power generation. There were found to be two main sources of inefficiency: 1. the 750W DC epicyclic generator performed poorly in low winds, and 2. the turbine blades wobbled, allowing for energy loss due to off-axis rotation. A 12V DC permanent magnet alternator was chosen that met the power requirements of the housing unit and would generate power at lower wind speeds. A support bracket was designed to prevent the turbine blades from wobbling.

  14. Irradiation for xenogeneic transplantation

    International Nuclear Information System (INIS)

    Halperin, E.C.; Knechtle, S.J.; Harland, R.C.; Yamaguchi, Yasua; Sontag, M.; Bollinger, R.R.; Duke Univ., Durham, NC

    1990-01-01

    Xenogeneic transplantation (XT) is the transplantation of organs or tissues from a member of one species to a member of another. Mammalian species frequently have circulating antibody which is directed against the foreign organ irrespective of known prior antigen exposure. This antibody may lead to hyperacute rejection once it ensues so efforts must be directed towards eliminating the pre-existing antibody. In those species in which hyperacute rejection of xenografts does not occur, cell-mediated refection, similar to allograft rejection, may occur. It is in the prevention of this latter form of refection that radiation is most likely to be beneficial in XT. Both total lymphoid irradiation (TLI) and selective lyphoid irradiation (LSI) have been investigated for use in conjunction with XT. TLI has contributed to the prolongation of pancreatic islet-cell xenografts from hamsters to rats. TLI has also markedly prolonged the survival of cardiac transplants from hamsters to rats. A more modest prolongation of graft survival has been seen with the use of TLI in rabbit-to-rat exchanges. Therapy with TLI, cyclosporine, and splenectomy has markedly prolonged the survival of liver transplants from hamsters to rats, and preliminary data suggest that TLI may contribute to the prolongation of graft survival in the transplantation of hearts from monkeys to baboons. SLI appears to have prolonged graft survival, when used in conjunction with anti-lymphocyte globulin, in hamster-to-rat cardiac graft exchanges. The current state of knowledge of the use of irradiaiton in experimental XT is reviewed. (author). 38 refs.; 1 fig.; 5 tabs

  15. From Bench to Bedside: Translating the Prolactin/Vasoinhibin Axis

    Directory of Open Access Journals (Sweden)

    Jakob Triebel

    2017-12-01

    Full Text Available The prolactin/vasoinhibin axis defines an endocrine system, in which prolactin (PRL and vasoinhibins regulate blood vessel growth and function, the secretion of other hormones, inflammatory and immune processes, coagulation, and behavior. The core element of the PRL/vasoinhibin axis is the generation of vasoinhibins, which consists in the proteolytic cleavage of their precursor molecule PRL. Vasoinhibins can interact with multiple different partners to mediate their effects in various tissues and anatomical compartments, indicating their pleiotropic nature. Based on accumulating knowledge about the PRL/vasoinhibin axis, two clinical trials were initiated, in which vasoinhibin levels are the target of therapeutic interventions. One trial investigates the effect of levosulpiride, a selective dopamine D2-receptor antagonist, on retinal alterations in patients with diabetic macular edema and retinopathy. The rationale of this trial is that the levosulpiride-induced hyperprolactinemia resulting in increased retinal vasoinhibins could lead to beneficiary outcomes in terms of a vasoinhibin-mediated antagonization of diabetes-induced retinal alterations. Another trial investigated the effect of bromocriptine, a dopamine D2-receptor agonist, for the treatment of peripartum cardiomyopathy. The rationale of treatment with bromocriptine is the inhibition of vasoinhibin generation by substrate depletion to prevent detrimental effects on the myocardial microvascularization. The trial demonstrated that bromocriptine treatment was associated with a high rate of left ventricular recovery and low morbidity and mortality. Therapeutic interventions into the PRL/vasoinhibin axis bear the risk of side effects in the areas of blood coagulation, blood pressure, and alterations of the mental state.

  16. Hysteresis Motor Driven One Axis Magnetically Suspended Reaction Sphere

    OpenAIRE

    Zhou, Lei; Nejad, Mohammad Imani; Trumper, David L.

    2014-01-01

    The Attitude and Orbit Control System (AOCS) plays an essential role in the flight control of a spacecraft. This system usually contains a minimum of three reaction wheels (often 4-5 wheels are used for optimization and redundancy). By accelerating the appropriate wheels, the system can produce a zero-mean reaction torque about any axis to the spacecraft, which enables the spacecraft to maneuver on orbit. Meanwhile, the momentum generated by acceleration can be stored in the wheels.

  17. Targeting the Ron-DEK Signaling Axis in Breast Cancer

    Science.gov (United States)

    2014-09-01

    2014.173 INTRODUCTION Despite high survival rates for early-stage breast cancer , it is still the second leading cause of cancer - related deaths in the...164: 285–293. 37 Adams AK, Hallenbeck GE, Casper KA, Patil YJ, Wilson KM, Kimple RJ et al. DEK promotes HPV -positive and -negative head and neck cancer ...AWARD NUMBER: W81XWH-12-1-0194 TITLE: Targeting the Ron-DEK Signaling Axis in Breast Cancer PRINCIPAL INVESTIGATORS: Dr

  18. Inelastic scattering using the three-axis spectrometer technique

    International Nuclear Information System (INIS)

    Currat, R.

    1999-01-01

    The three-axis technique is a basic neutron scattering technique for inelastic work on single-crystal specimens. There is, at the moment, a fair degree of complementarity between TAS instruments on steady-state sources and TOF instruments on steady-state or pulsed sources. The technique is described, the issue of TAS versus TOF method is discussed, and investigations relating to the resolution functions are presented. (K.A.)

  19. Gut-Brain Axis in Gastric Mucosal Damage and Protection.

    Science.gov (United States)

    Sgambato, Dolores; Capuano, Annalisa; Sullo, Maria Giuseppa; Miranda, Agnese; Federico, Alessandro; Romano, Marco

    2016-01-01

    The gut-brain axis plays a potential role in numerous physiological and pathological conditions. Several substances link stomach with central nervous system. In particular, hypothalamo-pituitary-adrenocortical axis, thyrotropinreleasing factor-containing nerve fibers and capsaicin-sensitive nerves are principal mediators of the harmful and protective central nervous system-mediated effects on gastric mucosa. Also, existing evidence indicates that nitric oxide, prostaglandins and calcitonin gene-related peptide play a role as final effectors of gastric protection. We undertook a structured search of bibliographic databases for peerreviewed research literature with the aim of focusing on the role of gut-brain axis in gastric damage and protection. In particular, we examined manuscripts dealing with the role of steroids, thyrotropin-releasing hormone, prostaglandins, melatonin, hydrogen sulfide and peptides influencing food intake (i.e. leptin, cholecystokinin, peptide YY, central glucagon-like peptide-1, and ghrelin). Also, the role of GABAergic and glutamatergic pathways in gastric mucosal protection have been examined. We found and reviewed 61 peer-reviewed papers dealing with the major aspects related to the role of gut brain axis in gastric mucosal damage and protection. A dense neuronal network links stomach with central nervous system and a number of neurotransmitters and peptides functionally and anatomically related to central nervous system play a major role in contributing to gastric mucosal integrity. Exploiting the mechanisms underlying the connection between brain and gut may lead to a better understanding of the pathophysiology of gastric mucosal injury and to an improvement in the prevention and, eventually, management of gastric damage.

  20. Intestinal barrier function and the brain-gut axis.

    Science.gov (United States)

    Alonso, Carmen; Vicario, María; Pigrau, Marc; Lobo, Beatriz; Santos, Javier

    2014-01-01

    The luminal-mucosal interface of the intestinal tract is the first relevant location where microorganism-derived antigens and all other potentially immunogenic particles face the scrutiny of the powerful mammalian immune system. Upon regular functioning conditions, the intestinal barrier is able to effectively prevent most environmental and external antigens to interact openly with the numerous and versatile elements that compose the mucosal-associated immune system. This evolutionary super system is capable of processing an astonishing amount of antigens and non-immunogenic particles, approximately 100 tons in one individual lifetime, only considering food-derived components. Most important, to develop oral tolerance and proper active immune responses needed to prevent disease and inflammation, this giant immunogenic load has to be managed in a way that physiological inflammatory balance is constantly preserved. Adequate functioning of the intestinal barrier involves local and distant regulatory networks integrating the so-called brain-gut axis. Along this complex axis both brain and gut structures participate in the processing and execution of response signals to external and internal changes coming from the digestive tract, using multidirectional pathways to communicate. Dysfunction of brain-gut axis facilitates malfunctioning of the intestinal barrier, and vice versa, increasing the risk of uncontrolled immunological reactions that may trigger mucosal and brain low-grade inflammation, a putative first step to the initiation of more permanent gut disorders. In this chapter, we describe the structure, function and interactions of intestinal barrier, microbiota and brain-gut axis in both healthy and pathological conditions.