The post-surgical era of GBM: How molecular biology has impacted on our clinical management. A review.

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Monticelli, M; Zeppa, P; Zenga, F; Altieri, R; Mammi, M; Bertero, L; Castellano, I; Cassoni, P; Melcarne, A; La Rocca, G; Sabatino, G; Ducati, A; Garbossa, D

2018-07-01

Glioblastoma (GBM) is the most common glioma in adults, with incidence increasing by 3% per year. According to the World Health Organization Classification of Central Nervous System Tumors, GBM is considered a grade IV tumor due to its malignant behavior. The aim of this review is to summarize the main biological aspects of GBM. In particular, we focused our attention on those alterations which have been proven to have an impact on patients' outcome, mainly in terms of overall survival (OS), or on the tumor response to therapies. We have also analyzed the cellular biology and the interactions between GBM and the surrounding environment. Copyright © 2018 Elsevier B.V. All rights reserved.

Podocyte Depletion in Thin GBM and Alport Syndrome.

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Wickman, Larysa; Hodgin, Jeffrey B; Wang, Su Q; Afshinnia, Farsad; Kershaw, David; Wiggins, Roger C

2016-01-01

The proximate genetic cause of both Thin GBM and Alport Syndrome (AS) is abnormal α3, 4 and 5 collagen IV chains resulting in abnormal glomerular basement membrane (GBM) structure/function. We previously reported that podocyte detachment rate measured in urine is increased in AS, suggesting that podocyte depletion could play a role in causing progressive loss of kidney function. To test this hypothesis podometric parameters were measured in 26 kidney biopsies from 21 patients aged 2-17 years with a clinic-pathologic diagnosis including both classic Alport Syndrome with thin and thick GBM segments and lamellated lamina densa [n = 15] and Thin GBM cases [n = 6]. Protocol biopsies from deceased donor kidneys were used as age-matched controls. Podocyte depletion was present in AS biopsies prior to detectable histologic abnormalities. No abnormality was detected by light microscopy at 70% podocyte depletion. Low level proteinuria was an early event at about 25% podocyte depletion and increased in proportion to podocyte depletion. These quantitative data parallel those from model systems where podocyte depletion is the causative event. This result supports a hypothesis that in AS podocyte adherence to the GBM is defective resulting in accelerated podocyte detachment causing progressive podocyte depletion leading to FSGS-like pathologic changes and eventual End Stage Kidney Disease. Early intervention to reduce podocyte depletion is projected to prolong kidney survival in AS.

GBM secretome induces transient transformation of human neural precursor cells.

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Venugopal, Chitra; Wang, X Simon; Manoranjan, Branavan; McFarlane, Nicole; Nolte, Sara; Li, Meredith; Murty, Naresh; Siu, K W Michael; Singh, Sheila K

2012-09-01

Glioblastoma (GBM) is the most aggressive primary brain tumor in humans, with a uniformly poor prognosis. The tumor microenvironment is composed of both supportive cellular substrates and exogenous factors. We hypothesize that exogenous factors secreted by brain tumor initiating cells (BTICs) could predispose normal neural precursor cells (NPCs) to transformation. When NPCs are grown in GBM-conditioned media, and designated as "tumor-conditioned NPCs" (tcNPCs), they become highly proliferative and exhibit increased stem cell self-renewal, or the unique ability of stem cells to asymmetrically generate another stem cell and a daughter cell. tcNPCs also show an increased transcript level of stem cell markers such as CD133 and ALDH and growth factor receptors such as VEGFR1, VEGFR2, EGFR and PDGFRα. Media analysis by ELISA of GBM-conditioned media reveals an elevated secretion of growth factors such as EGF, VEGF and PDGF-AA when compared to normal neural stem cell-conditioned media. We also demonstrate that tcNPCs require prolonged or continuous exposure to the GBM secretome in vitro to retain GBM BTIC characteristics. Our in vivo studies reveal that tcNPCs are unable to form tumors, confirming that irreversible transformation events may require sustained or prolonged presence of the GBM secretome. Analysis of GBM-conditioned media by mass spectrometry reveals the presence of secreted proteins Chitinase-3-like 1 (CHI3L1) and H2A histone family member H2AX. Collectively, our data suggest that GBM-secreted factors are capable of transiently altering normal NPCs, although for retention of the transformed phenotype, sustained or prolonged secretome exposure or additional transformation events are likely necessary.

Fermi GBM: Results from the First Year +

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Wilson-Hodge, Colleen A.

2009-01-01

Gamma-ray Burst Monitor (GBM) has performed well in the first year+. GBM triggers 353 Gamma-ray Bursts (GRBs), 168 SGR events, 18 TGFs, and 1 solar flare to date. Short GRBs appear contracted in time and shifted to higher energy than long GRBs. Pulsed persistent emission from SGR 1550-5418 detected. TGFs are shorter, have higher average photon energies, and much higher count rates than GRBs. GBM monitoring of accreting pulsars provides long-term spin-histories. GBM Earth occultation monitoring complements Swift.

A Proposal to Localize Fermi GBM GRBs Through Coordinated Scanning of the GBM Error Circle via Optical Telescopes

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Ukwatta, T. N.; Linnemann, J. T.; Tollefson, K.; Abeysekara, A. U.; Bhat, P. N.; Sonbas, E.; Gehrels, N.

2011-01-01

We investigate the feasibility of implementing a system that will coordinate ground-based optical telescopes to cover the Fermi GBM Error Circle (EC). The aim of the system is to localize GBM detected GRBs and facilitate multi-wavelength follow-up from space and ground. This system will optimize the observing locations in the GBM EC based on individual telescope location, Field of View (FoV) and sensitivity. The proposed system will coordinate GBM EC scanning by professional as well as amateur astronomers around the world. The results of a Monte Carlo simulation to investigate the feasibility of the project are presented.

Diagnosis and classification of Goodpasture's disease (anti-GBM).

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Hellmark, Thomas; Segelmark, Mårten

2014-01-01

Goodpasture's disease or anti-glomerular basement membrane disease (anti-GBM-disease) is included among immune complex small vessel vasculitides. The definition of anti-GBM disease is a vasculitis affecting glomerular capillaries, pulmonary capillaries, or both, with GBM deposition of anti-GBM autoantibodies. The disease is a prototype of autoimmune disease, where the patients develop autoantibodies that bind to the basement membranes and activate the classical pathway of the complement system, which start a neutrophil dependent inflammation. The diagnosis of anti-GBM disease relies on the detection of anti-GBM antibodies in conjunction with glomerulonephritis and/or alveolitis. Overt clinical symptoms are most prominent in the glomeruli where the inflammation usually results in a severe rapidly progressive glomerulonephritis. Despite modern treatment less than one third of the patients survive with a preserved kidney function after 6 months follow-up. Frequencies vary from 0.5 to 1 cases per million inhabitants per year and there is a strong genetic linkage to HLA-DRB1(∗)1501 and DRB1(∗)1502. Essentially, anti-GBM disease is now a preferred term for what was earlier called Goodpasture's syndrome or Goodpasture's disease; anti-GBM disease is now classified as small vessel vasculitis caused by in situ immune complex formation; the diagnosis relies on the detection of anti-GBM in tissues or circulation in conjunction with alveolar or glomerular disease; therapy is effective only when detected at an early stage, making a high degree of awareness necessary to find these rare cases; 20-35% have anti-GBM and MPO-ANCA simultaneously, which necessitates testing for anti-GBM whenever acute test for ANCA is ordered in patients with renal disease. Copyright © 2014 Elsevier Ltd. All rights reserved.

Urinary cystatin C as a renal biomarker and its immunohistochemical localization in anti-GBM glomerulonephritis rats.

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Togashi, Yuko; Imura, Naoko; Miyamoto, Yohei

2013-11-01

The usefulness of urinary cystatin C for the early detection of renal damage in anti-glomerular basement membrane (GBM) glomerulonephritis rats was investigated and compared to other biomarkers (β2-microglobulin, calbindin, clusterin, epidermal growth factor (EGF), alpha-glutathione S-transferase (GST-α), mu-glutathione S-transferase (GST-μ), kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), osteopontin, tissue inhibitor of metalloprotease-1 (TIMP-1), and vascular endothelial growth factor (VEGF)). Urinary levels of cystatin C increased in anti-GBM glomerulonephritis rats, whereas the conventional markers, plasma creatinine and UN did not, demonstrating its usefulness for the early detection of renal damage associated with anti-GBM glomerulonephritis. As well as cystatin C, urinary β2-microglobulin, clusterin, GST-α, GST-μ, KIM-1, and NGAL also had the potential to detect renal damage associated with anti-GBM glomerulonephritis. Furthermore, the immunohistochemical localization of cystatin C in the kidney was examined. Cystatin C expression was mainly observed in the proximal renal tubules in anti-GBM glomerulonephritis rats, and its expression barely changed with the progression of glomerulonephritis. Cystatin C expression was also observed in the tubular lumen of the cortex and medulla when glomerulonephritis was marked, which was considered to be characteristic of renal damage. In conclusion, urinary cystatin C, β2-microglobulin, clusterin, GST-α, GST-μ, KIM-1, and NGAL could be useful biomarkers of renal damage in anti-GBM glomerulonephritis rats. Immunohistochemical cystatin C expression in the proximal renal tubules was barely changed by the progression of glomerulonephritis, but it was newly observed in the tubular lumen when renal damage was apparent. Crown Copyright © 2013. Published by Elsevier GmbH. All rights reserved.

Neutrophil degranulation and immunosuppression in patients with GBM: restoration of cellular immune function by targeting arginase I.

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Sippel, Trisha R; White, Jason; Nag, Kamalika; Tsvankin, Vadim; Klaassen, Marci; Kleinschmidt-DeMasters, B K; Waziri, Allen

2011-11-15

The source of glioblastoma (GBM)-associated immunosuppression remains multifactorial. We sought to clarify and therapeutically target myeloid cell-derived peripheral immunosuppression in patients with GBM. Direct ex vivo T-cell function, serum Arginase I (ArgI) levels, and circulating myeloid lineage populations were compared between patients with GBM and normal donors or patients with other intracranial tumors. Immunofunctional assays were conducted using bulk and sorted cell populations to explore the potential transfer of myeloid cell-mediated immunosuppression and to identify a potential mechanism for these effects. ArgI-mediated immunosuppression was therapeutically targeted in vitro through pharmacologic inhibition or arginine supplementation. We identified a significantly expanded population of circulating, degranulated neutrophils associated with elevated levels of serum ArgI and decreased T-cell CD3ζ expression within peripheral blood from patients with GBM. Sorted CD11b(+) cells from patients with GBM were found to markedly suppress normal donor T-cell function in coculture, and media harvested from mitogen-stimulated GBM peripheral blood mononuclear cell (PBMC) or GBM-associated mixed lymphoid reactions showed ArgI levels that were significantly higher than controls. Critically, T-cell suppression in both settings could be completely reversed through pharmacologic ArgI inhibition or with arginine supplementation. These data indicate that peripheral cellular immunosuppression in patients with GBM is associated with neutrophil degranulation and elevated levels of circulating ArgI, and that T-cell function can be restored in these individuals by targeting ArgI. These data identify a novel pathway of GBM-mediated suppression of cellular immunity and offer a potential therapeutic window for improving antitumor immunity in affected patients.

Dismantling of the EB experiment: Experimental research on the retrieved GBM and bentonite blocks

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Liu, Jiang-Feng, E-mail: jeafliu@hotmail.com [State Key Laboratory for Geomchanics & Deep Underground Engineering, and School of Mechanics and Civil Engineering, China University of Mining & Technology, Xuzhou, Jiangsu 221116 (China); Laboratoire de Méchanique de Lille (LML), and École Centrale de Lille, BP 48, F-59651 Villeneuve d’Ascq Cedex (France); Skoczylas, Frédéric [Laboratoire de Méchanique de Lille (LML), and École Centrale de Lille, BP 48, F-59651 Villeneuve d’Ascq Cedex (France); Talandier, Jean [ANDRA, 1-7 rue Jean Monnet, 92298 Châtenay-Malabry Cedex (France); Pu, Hai [State Key Laboratory for Geomchanics & Deep Underground Engineering, and School of Mechanics and Civil Engineering, China University of Mining & Technology, Xuzhou, Jiangsu 221116 (China)

2016-04-15

Graphical abstract: - Highlights: • We present a demonstration of a new concept of HLW (high-level waste) repositories. • The hydro-mechanical characteristics of GBM and blocks were determined. • The water retention curves (WRCs) of GBM and blocks were presented. • The effective gas permeability of the GBM and blocks were measured. • The homogeneity of the GBM and blocks were investigated. - Abstract: The Engineered Barrier Emplacement Experiment in Opalinus Clay (EB experiment) was a full-scale test for the demonstration of a new concept of high-level waste (HLW) repositories in horizontal drifts in the Opalinus Clay formation. After 10.5 years of hydration, the EB experiment was dismantled in autumn 2012. Samples obtained from the granular bentonite material (GBM), and bentonite blocks were sent to a laboratory for further analysis. The bentonite samples analyzed at the Laboratory of Mechanic of Lille (LML) were obtained from the CMT1, CMT2, CMT3 and RW sections. Their physical states were determined, as were their effective gas permeability and swelling capacity at different relative humidity (RH) levels. The results indicate that the water contents of the GBM determined in the laboratory ranged between 25.63% and 44.88% and that the dry densities ranged between 1.13 and 1.44 g/cm{sup 3}. The blocks had water contents similar to (or slightly higher than) those of the GBM, and their dry densities had decreased from an initial value of 1.69 g/cm{sup 3} to values close to 1.30 g/cm{sup 3}, which were similar to the average values found in the GBM. The effective gas permeabilities of the GBM samples were within the range of 1.50 × 10{sup −22} m{sup 2} and 1.03 × 10{sup −17} m{sup 2}, whereas, the corresponding values of the samples obtained from the blocks were between 2.20 × 10{sup −21} m{sup 2} and 5.12 × 10{sup −21} m{sup 2}. The permeability values are primarily related to the dry densities and water contents of the samples. Contact with

Investigating a signature of temozolomide resistance in GBM cell lines using metabolomics.

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St-Coeur, Patrick-Denis; Poitras, Julie J; Cuperlovic-Culf, Miroslava; Touaibia, Mohamed; Morin, Pier

2015-10-01

Glioblastoma multiforme (GBM) is the most common form of malignant glioma. Current therapeutic approach to treat this malignancy involves a combination of surgery, radiotherapy and chemotherapy with temozolomide. Numerous mechanisms contributing to inherent and acquired resistance to this chemotherapeutic agent have been identified and can lead to treatment failure. This study undertook a metabolomics-based approach to characterize the metabolic profiles observed in temozolomide-sensitive and temozolomide-resistant GBM cell lines as well as in a small sub-set of primary GBM tumors. This approach was also utilized to explore the metabolic changes modulated upon cell treatment with temozolomide and lomeguatrib, an MGMT inhibitor with temozolomide-sensitizing potential. Metabolites previously explored for their potential role in chemoresistance including glucose, citrate and isocitrate demonstrated elevated levels in temozolomide-resistant GBM cells. In addition, a signature of metabolites comprising alanine, choline, creatine and phosphorylcholine was identified as up-regulated in sensitive GBM cell line across different treatments. These results present the metabolic profiles associated with temozolomide response in selected GBM models and propose interesting leads that could be leveraged for the development of therapeutic or diagnostic tools to impact temozolomide response in GBMs.

Magnetar Observations with Fermi/GBM

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Kouveliotou, Chryssa

2009-01-01

NASA's Fermi Observatory was launched June 11, 2009; the Fermi Gamma Ray Burst Monitor (GBM) began normal operations on July 14, about a month after launch, when the trigger algorithms were enabled. In the first year of operations we recorded emission from four magnetar sources; of these, only one was an old magnetar: SGR 1806+20. The other three detections were: SGR J0501+4516, newly discovered with Swift and extensively monitored with both Swift and GBM, SGR J1550-5418, a source originally classified as an Anomalous X-ray Pulsar (AXP) and a very recently discovered new source, SGR 0418+5729. I report below on the current status of the analyses efforts of the GBM data.

A small noncoding RNA signature found in exosomes of GBM patient serum as a diagnostic tool.

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Manterola, Lorea; Guruceaga, Elizabeth; Gállego Pérez-Larraya, Jaime; González-Huarriz, Marisol; Jauregui, Patricia; Tejada, Sonia; Diez-Valle, Ricardo; Segura, Victor; Samprón, Nicolás; Barrena, Cristina; Ruiz, Irune; Agirre, Amaia; Ayuso, Angel; Rodríguez, Javier; González, Alvaro; Xipell, Enric; Matheu, Ander; López de Munain, Adolfo; Tuñón, Teresa; Zazpe, Idoya; García-Foncillas, Jesús; Paris, Sophie; Delattre, Jean Yves; Alonso, Marta M

2014-04-01

Glioblastoma multiforme (GBM) is the most frequent malignant brain tumor in adults, and its prognosis remains dismal despite intensive research and therapeutic advances. Diagnostic biomarkers would be clinically meaningful to allow for early detection of the tumor and for those cases in which surgery is contraindicated or biopsy results are inconclusive. Recent findings show that GBM cells release microvesicles that contain a select subset of cellular proteins and RNA. The aim of this hypothesis-generating study was to assess the diagnostic potential of miRNAs found in microvesicles isolated from the serum of GBM patients. To control disease heterogeneity, we used patients with newly diagnosed GBM. In the discovery stage, PCR-based TaqMan Low Density Arrays followed by individual quantitative reverse transcriptase polymerase chain reaction were used to test the differences in the miRNA expression levels of serum microvesicles among 25 GBM patients and healthy controls paired by age and sex. The detected noncoding RNAs were then validated in another 50 GBM patients. We found that the expression levels of 1 small noncoding RNA (RNU6-1) and 2 microRNAs (miR-320 and miR-574-3p) were significantly associated with a GBM diagnosis. In addition, RNU6-1 was consistently an independent predictor of a GBM diagnosis. Altogether our results uncovered a small noncoding RNA signature in microvesicles isolated from GBM patient serum that could be used as a fast and reliable differential diagnostic biomarker.

Performance evaluation of a novel chemiluminescence assay for detection of anti-GBM antibodies: an international multicenter study.

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Mahler, Michael; Radice, Antonella; Sinico, Renato A; Damoiseaux, Jan; Seaman, Andrea; Buckmelter, Kristen; Vizjak, Alenka; Buchner, Carol; Binder, Walter L; Fritzler, Marvin J; Cui, Zhao

2012-01-01

Autoantibodies to the non-collagen region (NC1) of the alpha-3 subunit of collagen IV represent a serological hallmark in the diagnosis of Goodpasture's syndrome (GPS). The objective of our study was to carefully analyze the performance characteristics of a novel anti-glomerular basement membrane (GBM) chemiluminescence immunoassay (CIA). Sera from patients with GPS (n = 90) were collected from four clinical centers. Samples from different disease groups (n = 397) and healthy individuals (n = 400) were used as controls. All samples were tested for anti-GBM antibodies by a rapid, random access CIA (QUANTA Flash™ GBM). Most of the samples were also tested using other methods including different commercial anti-GBM IgG assays and research assays for anti-GBM IgA and IgM. The sensitivity and specificity of the novel CIA was 95.6% [95% confidence interval (CI) 89.0-98.8%] and 99.6% (95% CI 98.9-99.9%), respectively. Receiver operating characteristic analysis showed good discrimination between GPS patients and controls. The area under the curve was 0.98 (CI 0.96-1.0). The three anti-GBM antibody-positive samples from the control group were from two healthy individuals and one human immunodeficiency virus (HIV)-infected patient. All three individuals had low levels of anti-GBM antibodies [20, 24 and 25 chemiluminescent unit (CU), cutoff 20 CU]. When the results of the new CIA were compared to other methods, good agreement was observed: 95.8% (kappa = 0.92) versus EliA™ GBM, 97.4% (kappa = 0.95) versus both BINDAZYME™ Anti-GBM and QUANTA Lite® GBM. Anti-GBM IgA was detectable in low concentrations in patients with GPS and was associated with anti-GBM IgG but was less useful in discriminating GPS patients and controls. No discrimination was found for anti-GBM IgM. The novel QUANTA Flash™ GBM CIA demonstrated good sensitivity and specificity and had good agreement with other methods. Our data confirm that ∼5% of patients with GPS do not have detectable levels of

Current status and future therapeutic perspectives of glioblastoma multiforme (GBM) therapy: A review.

Science.gov (United States)

Anjum, Komal; Shagufta, Bibi Ibtesam; Abbas, Syed Qamar; Patel, Seema; Khan, Ishrat; Shah, Sayed Asmat Ali; Akhter, Najeeb; Hassan, Syed Shams Ul

2017-08-01

Glioblastoma multiforme (GBM) is the deadliest form of heterogeneous brain cancer. It affects an enormous number of patients every year and the survival is approximately 8 to 15 months. GBM has driven by complex signaling pathways and considered as a most challenging to treat. Standard treatment of GBM includes surgery, radiation therapy, chemotherapy and also the combined treatment. This review article described inter and intra- tumor heterogeneity of GMB. In addition, recent chemotherapeutic agents, with their mechanism of action have been defined. FDA-approved drugs also been focused over here and most importantly highlighting some natural and synthetic and novel anti- glioma agents, that are the main focus of researchers nowadays. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

USP1 targeting impedes GBM growth by inhibiting stem cell maintenance and radioresistance.

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Lee, Jin-Ku; Chang, Nakho; Yoon, Yeup; Yang, Heekyoung; Cho, Heejin; Kim, Eunhee; Shin, Yongjae; Kang, Wonyoung; Oh, Young Taek; Mun, Gyeong In; Joo, Kyeung Min; Nam, Do-Hyun; Lee, Jeongwu

2016-01-01

Clinical benefits from standard therapies against glioblastoma (GBM) are limited in part due to intrinsic radio- and chemoresistance of GBM and inefficient targeting of GBM stem-like cells (GSCs). Novel therapeutic approaches that overcome treatment resistance and diminish stem-like properties of GBM are needed. We determined the expression levels of ubiquitination-specific proteases (USPs) by transcriptome analysis and found that USP1 is highly expressed in GBM. Using the patient GBM-derived primary tumor cells, we inhibited USP1 by shRNA-mediated knockdown or its specific inhibitor pimozide and evaluated the effects on stem cell marker expression, proliferation, and clonogenic growth of tumor cells. USP1 was highly expressed in gliomas relative to normal brain tissues and more preferentially in GSC enrichment marker (CD133 or CD15) positive cells. USP1 positively regulated the protein stability of the ID1 and CHEK1, critical regulators of DNA damage response and stem cell maintenance. Targeting USP1 by RNA interference or treatment with a chemical USP1 inhibitor attenuated clonogenic growth and survival of GSCs and enhanced radiosensitivity of GBM cells. Finally, USP1 inhibition alone or in combination with radiation significantly prolonged the survival of tumor-bearing mice. USP1-mediated protein stabilization promotes GSC maintenance and treatment resistance, thereby providing a rationale for USP1 inhibition as a potential therapeutic approach against GBM. © 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.

Characterization of Metabolic, Diffusion, and Perfusion Properties in GBM: Contrast-Enhancing versus Non-Enhancing Tumor

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Adam Autry

2017-12-01

Full Text Available BACKGROUND: Although the contrast-enhancing (CE lesion on T1-weighted MR images is widely used as a surrogate for glioblastoma (GBM, there are also non-enhancing regions of infiltrative tumor within the T2-weighted lesion, which elude radiologic detection. Because non-enhancing GBM (Enh− challenges clinical patient management as latent disease, this study sought to characterize ex vivo metabolic profiles from Enh− and CE GBM (Enh+ samples, alongside histological and in vivo MR parameters, to assist in defining criteria for estimating total tumor burden. Methods: Fifty-six patients with newly diagnosed GBM received a multi-parametric pre-surgical MR examination. Targets for obtaining image-guided tissue samples were defined based on in vivo parameters that were suspicious for tumor. The actual location from where tissue samples were obtained was recorded, and half of each sample was analyzed for histopathology while the other half was scanned using HR-MAS spectroscopy. Results: The Enh+ and Enh− tumor samples demonstrated comparable mitotic activity, but also significant heterogeneity in microvascular morphology. Ex vivo spectroscopic parameters indicated similar levels of total choline and N-acetylaspartate between these contrast-based radiographic subtypes of GBM, and characteristic differences in the levels of myo-inositol, creatine/phosphocreatine, and phosphoethanolamine. Analysis of in vivo parameters at the sample locations were consistent with histological and ex vivo metabolic data. CONCLUSIONS: The similarity between ex vivo levels of choline and NAA, and between in vivo levels of choline, NAA and nADC in Enh+ and Enh− tumor, indicate that these parameters can be used in defining non-invasive metrics of total tumor burden for patients with GBM.

Characterization of Metabolic, Diffusion, and Perfusion Properties in GBM: Contrast-Enhancing versus Non-Enhancing Tumor.

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Autry, Adam; Phillips, Joanna J; Maleschlijski, Stojan; Roy, Ritu; Molinaro, Annette M; Chang, Susan M; Cha, Soonmee; Lupo, Janine M; Nelson, Sarah J

2017-12-01

Although the contrast-enhancing (CE) lesion on T 1 -weighted MR images is widely used as a surrogate for glioblastoma (GBM), there are also non-enhancing regions of infiltrative tumor within the T 2 -weighted lesion, which elude radiologic detection. Because non-enhancing GBM (Enh-) challenges clinical patient management as latent disease, this study sought to characterize ex vivo metabolic profiles from Enh- and CE GBM (Enh+) samples, alongside histological and in vivo MR parameters, to assist in defining criteria for estimating total tumor burden. Fifty-six patients with newly diagnosed GBM received a multi-parametric pre-surgical MR examination. Targets for obtaining image-guided tissue samples were defined based on in vivo parameters that were suspicious for tumor. The actual location from where tissue samples were obtained was recorded, and half of each sample was analyzed for histopathology while the other half was scanned using HR-MAS spectroscopy. The Enh+ and Enh- tumor samples demonstrated comparable mitotic activity, but also significant heterogeneity in microvascular morphology. Ex vivo spectroscopic parameters indicated similar levels of total choline and N-acetylaspartate between these contrast-based radiographic subtypes of GBM, and characteristic differences in the levels of myo-inositol, creatine/phosphocreatine, and phosphoethanolamine. Analysis of in vivo parameters at the sample locations were consistent with histological and ex vivo metabolic data. The similarity between ex vivo levels of choline and NAA, and between in vivo levels of choline, NAA and nADC in Enh+ and Enh- tumor, indicate that these parameters can be used in defining non-invasive metrics of total tumor burden for patients with GBM. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

High-energy emission from bright gamma-ray bursts using Fermi

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Bissaldi, Elisabetta

2010-05-25

mainly based on the brightest bursts detected by GBM inside the LAT field-of-view. The determination of a consistent sample for upper-limit calculations can be established by selecting those bursts which have a strong signal in the GBM BGO detectors. The structure of this thesis can be summarized as follows: The first chapter introduces the basic concepts and scientific background of GRB physics. Afterwards, instrumental details about the Fermi instruments LAT and GBM, as well as LAT performance and capabilities for GRB science are presented in chapter 2. Chapter 3 focuses on the detector-level calibration of the GBM instrument, and in particular on the analysis methods and results, which crucially support the development of a consistent GBM instrument response. The main GBM scientific results collected during the first year of operation are then presented in chapter 4. Particular emphasis is given to the description of joint GBM-LAT and GBM-Swift observations and analysis results. The last chapter presents the selection methodology and detailed spectral analysis of a sample of well-defined BGO-bright bursts detected by GBM during its first year. Using these results, correlations among spectral parameters are finally discussed. (orig.)

High-energy emission from bright gamma-ray bursts using Fermi

International Nuclear Information System (INIS)

Bissaldi, Elisabetta

2010-01-01

on the brightest bursts detected by GBM inside the LAT field-of-view. The determination of a consistent sample for upper-limit calculations can be established by selecting those bursts which have a strong signal in the GBM BGO detectors. The structure of this thesis can be summarized as follows: The first chapter introduces the basic concepts and scientific background of GRB physics. Afterwards, instrumental details about the Fermi instruments LAT and GBM, as well as LAT performance and capabilities for GRB science are presented in chapter 2. Chapter 3 focuses on the detector-level calibration of the GBM instrument, and in particular on the analysis methods and results, which crucially support the development of a consistent GBM instrument response. The main GBM scientific results collected during the first year of operation are then presented in chapter 4. Particular emphasis is given to the description of joint GBM-LAT and GBM-Swift observations and analysis results. The last chapter presents the selection methodology and detailed spectral analysis of a sample of well-defined BGO-bright bursts detected by GBM during its first year. Using these results, correlations among spectral parameters are finally discussed. (orig.)

Time-Domain Astronomy with the Fermi GBM

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Hui, C. M.

2017-01-01

The Fermi Gamma-ray Burst Monitor (GBM) is an all-sky monitoring instrument sensitive to energies from 8 keV to 40 MeV. Over the past 8 years of operation, the GBM has detected over 240 gamma-ray bursts per year and provided timely GCN notices with localization to few-degree accuracy for follow-up observations. In addition to GRBs, Galactic transients, solar flares, and terrestrial gamma-ray flashes have also been observed. In recent years we have also been searching the continuous GBM data for electromagnetic counterpart to astrophysical neutrinos and gravitational wave events, as these are believed to be associated with gamma-ray bursts. With continuous data downlink every few hours and a temporal resolution of 2 microseconds, GBM is well suited for observing transients and supporting EM follow-up in the era of multi-messenger astronomy.

The Successful Synergy of Swift and Fermi/GBM in Magnetars

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Kouveliotou, Chryssa

2011-01-01

The magnetar rate of discovery has increased dramatically in the last decade. Five sources were discovered in the last three years alone as a result of the very efficient synergy among three X- and .gamma-ray instruments on NASA satellites: the Swift/Burst Alert Telescope (BAT), the Fermi/Gamma ray Burst Monitor (GBM), and the Rossi X-Ray Timing Explorer; RXTE/Proportional Counter Array (PCA). To date, there are approx. 25 magnetar candidates, of which two are (one each) in the Large and Small Magellanic Cloud and the rest reside on the Galactic plane of our Milky Way. I will discuss here the main properties of the Magnetar Population and the common projects that can be achieved with the synergy of Swift and GBM.

GBM Observations of Terrestrial Gamma-Ray Flashes

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Briggs, M. S.; Fishman, G. J.; Connaughton, V.; Bhat, P. N.; Paciesas, W. S.; Preece, R. D.; Wilson-Hodge, C.; Chaplin, V. L.; Kippen, R. M.; vonKienlin, A.;

Three years of Transients with Fermi GBM

Science.gov (United States)

Wilson-Hodge, Colleen A.

2012-01-01

The Gamma-ray Burst Monitor (GBM) is an all-sky monitoring instrument, sensitive between 8 keV and 40 MeV, with a primary objective of supporting the Large Area Telescope (LAT) in observations of Gamma-Ray Bursts (GRBs). Both instruments are part of the Fermi Gamma-ray Space Telescope. Together, the GBM and LAT instruments have provided ground-breaking measurements of GRBs that have, after 10 years of focus on GRB afterglows, inspired renewed interest in the prompt emission phase of GRBs and the physical mechanisms that fuel them. In addition to GRB science, GBM has made significant contributions to the astrophysics of galactic transient sources including long-term variations in the Crab nebula, spin state transitions in accretion powered pulsars, state transitions in black hole X-ray binaries, and unprecedented time-resolved spectral studies of soft gamma-ray repeater bursts. Closer to home, GBM also contributes to solar flare and terrestrial gamma flash science.

Anti-SEMA3A Antibody: A Novel Therapeutic Agent to Suppress GBM Tumor Growth.

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Lee, Jaehyun; Shin, Yong Jae; Lee, Kyoungmin; Cho, Hee Jin; Sa, Jason K; Lee, Sang-Yun; Kim, Seok-Hyung; Lee, Jeongwu; Yoon, Yeup; Nam, Do-Hyun

2017-11-10

Glioblastoma (GBM) is classified as one of the most aggressive and lethal brain tumor. Great strides have been made in understanding the genomic and molecular underpinnings of GBM, which translated into development of new therapeutic approaches to combat such deadly disease. However, there are only few therapeutic agents that can effectively inhibit GBM invasion in a clinical framework. In an effort to address such challenges, we have generated anti-SEMA3A monoclonal antibody as a potential therapeutic antibody against GBM progression. We employed public glioma datasets, Repository of Molecular Brain Neoplasia Data and The Cancer Genome Atlas, to analyze SEMA3A mRNA expression in human GBM specimens. We also evaluated for protein expression level of SEMA3A via tissue microarray (TMA) analysis. Cell migration and proliferation kinetics were assessed in various GBM patient-derived cells (PDCs) and U87-MG cell-line for SEMA3A antibody efficacy. GBM patient-derived xenograft (PDX) models were generated to evaluate tumor inhibitory effect of anti-SEMA3A antibody in vivo. By combining bioinformatics and TMA analysis, we discovered that SEMA3A is highly expressed in human GBM specimens compared to non-neoplastic tissues. We developed three different anti-SEMA3A antibodies, in fully human IgG form, through screening phage-displayed synthetic antibody library using a classical panning method. Neutralization of SEMA3A significantly reduced migration and proliferation capabilities of PDCs and U87-MG cell-line in vitro. In PDX models, treatment with anti-SEMA3A antibody exhibited notable tumor inhibitory effect through down-regulation of cellular proliferative kinetics and tumor-associated macrophages recruitment. In present study, we demonstrated tumor inhibitory effect of SEMA3A antibody in GBM progression and present its potential relevance as a therapeutic agent in a clinical framework.

Liposomal TriCurin, A Synergistic Combination of Curcumin, Epicatechin Gallate and Resveratrol, Repolarizes Tumor-Associated Microglia/Macrophages, and Eliminates Glioblastoma (GBM) and GBM Stem Cells.

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Mukherjee, Sumit; Baidoo, Juliet N E; Sampat, Samay; Mancuso, Andrew; David, Lovena; Cohen, Leah S; Zhou, Shuiqin; Banerjee, Probal

2018-01-18

Glioblastoma (GBM) is a deadly brain tumor with a current mean survival of 12-15 months. Despite being a potent anti-cancer agent, the turmeric ingredient curcumin (C) has limited anti-tumor efficacy in vivo due to its low bioavailability. We have reported earlier a strategy involving the use two other polyphenols, epicatechin gallate (E) from green tea and resveratrol (R) from red grapes at a unique, synergistic molar ratio with C (C:E:R: 4:1:12.5, termed TriCurin) to achieve superior potency against HPV+ tumors than C alone at C:E:R (μM): 32:8:100 (termed 32 μM+ TriCurin). We have now prepared liposomal TriCurin (TrLp) and demonstrated that TrLp boosts activated p53 in cultured GL261 mouse GBM cells to trigger apoptosis of GBM and GBM stem cells in vitro. TrLp administration into mice yielded a stable plasma concentration of 210 nM C for 60 min, which, though sub-lethal for cultured GL261 cells, was able to cause repolarization of M2-like tumor (GBM)-associated microglia/macrophages to the tumoricidal M1-like phenotype and intra-GBM recruitment of activated natural killer cells. The intratumor presence of such tumoricidal immune cells was associated with concomitant suppression of tumor-load, and apoptosis of GBM and GBM stem cells. Thus, TrLp is a potential onco-immunotherapeutic agent against GBM tumors.

Liposomal TriCurin, A Synergistic Combination of Curcumin, Epicatechin Gallate and Resveratrol, Repolarizes Tumor-Associated Microglia/Macrophages, and Eliminates Glioblastoma (GBM and GBM Stem Cells

Directory of Open Access Journals (Sweden)

Sumit Mukherjee

2018-01-01

Full Text Available Glioblastoma (GBM is a deadly brain tumor with a current mean survival of 12–15 months. Despite being a potent anti-cancer agent, the turmeric ingredient curcumin (C has limited anti-tumor efficacy in vivo due to its low bioavailability. We have reported earlier a strategy involving the use two other polyphenols, epicatechin gallate (E from green tea and resveratrol (R from red grapes at a unique, synergistic molar ratio with C (C:E:R: 4:1:12.5, termed TriCurin to achieve superior potency against HPV+ tumors than C alone at C:E:R (μM: 32:8:100 (termed 32 μM+ TriCurin. We have now prepared liposomal TriCurin (TrLp and demonstrated that TrLp boosts activated p53 in cultured GL261 mouse GBM cells to trigger apoptosis of GBM and GBM stem cells in vitro. TrLp administration into mice yielded a stable plasma concentration of 210 nM C for 60 min, which, though sub-lethal for cultured GL261 cells, was able to cause repolarization of M2-like tumor (GBM-associated microglia/macrophages to the tumoricidal M1-like phenotype and intra-GBM recruitment of activated natural killer cells. The intratumor presence of such tumoricidal immune cells was associated with concomitant suppression of tumor-load, and apoptosis of GBM and GBM stem cells. Thus, TrLp is a potential onco-immunotherapeutic agent against GBM tumors.

Glioblastoma with oligodendroglioma component (GBM-O): molecular genetic and clinical characteristics.

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Appin, Christina L; Gao, Jingjing; Chisolm, Candace; Torian, Mike; Alexis, Dianne; Vincentelli, Cristina; Schniederjan, Matthew J; Hadjipanayis, Costas; Olson, Jeffrey J; Hunter, Stephen; Hao, Chunhai; Brat, Daniel J

2013-07-01

Glioblastoma (GBM) is an aggressive primary brain tumor with an average survival of approximately 1 year. A recently recognized subtype, glioblastoma with oligodendroglioma component (GBM-O), was designated by the World Health Organization (WHO) in 2007. We investigated GBM-Os for their clinical and molecular characteristics as compared to other forms of GBM. Tissue samples were used to determine EGFR, PTEN, and 1p and 19q status by fluorescence in situ hybridization (FISH); p53 and mutant IDH1 protein expression by immunohistochemistry (IHC); and MGMT promoter status by methylation-specific polymerase chain reaction (PCR). GBM-Os accounted for 11.9% of all GBMs. GBM-Os arose in younger patients compared to other forms of GBMs (50.7 years vs. 58.7 years, respectively), were more frequently secondary neoplasms, had a higher frequency of IDH1 mutations and had a lower frequency of PTEN deletions. Survival was longer in patients with GBM-Os compared to those with other GBMs, with median survivals of 16.2 and 8.1 months, respectively. Most of the survival advantage for GBM-O appeared to be associated with a younger age at presentation. Among patients with GBM-O, younger age at presentation and 1p deletion were most significant in conferring prolonged survival. Thus, GBM-O represents a subset of GBMs with distinctive morphologic, clinical and molecular characteristics. © 2013 The Authors; Brain Pathology © 2013 International Society of Neuropathology.

The Fermi GBM catalog (Paciesas+, 2012) [Dataset

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Paciesas, W.S.; Meegan, C.A.; von Kienlin, A.; Bhat, P.N.; Bissaldi, E.; Briggs, M.S.; Burgess, J.M.; Chaplin, V.; Connaughton, V.; Diehl, R.; Fishman, G.J.; Fitzpatrick, G.; Foley, S.; H. Gibby, M.; Giles, M.; Goldstein, A.; Greiner, J.; Gruber, D.; Guiriec, S.; van der Horst, A.J.; Kippen, R.M.; Kouveliotou, C.; Lichti, G.; Lin, L.; McBreen, S.; Preece, R.D.; Rau, A.; Tierney, D.; Wilson-Hodge, C.

2012-01-01

The Fermi Gamma-ray Space Telescope was launched on 2008 June 11 on a mission to study the universe at high energies. The onboard Gamma-ray Burst Monitor (GBM) trigger system for detecting GRBs was first enabled on 2008 July 12. In this paper, we provide a catalog of GRBs that triggered the GBM

Magnetar Observations in the Swift-Fermi/GBM Era

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Kouveliotou, Chryssa

2010-01-01

NASA's Fermi Observatory was launched June 11, 2008; the Fermi Gamma Ray Burst Monitor (GBM) began normal operations on July 14, about a month after launch, when the trigger algorithms were enabled. Since then, and against all odds, GBM recorded over 600 bursts from 4 SGRs. Of these four sources, only one was an old magnetar: SGR J1806+20. SGR J0501+4516, was discovered with Swift and extensively monitored with GBM. A source originally classified as AXP 1E1547.0-5408 exhibited SGR-like bursting behavior and we reclassified it as SGR J1550-5418. Finally, GBM discovered SGR J0418+5729 on 2009 June. Finally, on March 2010, a third new magnetar was discovered with Swift, SGR J1833-0832. I report below on the current status of the field and on several results combining multi-satellite and ground-based data

The validity of EORTC GBM prognostic calculator on survival of GBM patients in the West of Scotland.

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Teo, Mario; Clark, Brian; MacKinnon, Mairi; Stewart, Willie; Paul, James; St George, Jerome

2014-06-01

It is now accepted that the addition of temozolomide to radiotherapy in the treatment of patients with newly diagnosed glioblastoma multiforme (GBM) significantly improves survival. In 2008, a subanalysis of the original study data was performed, and an online "GBM Calculator" was made available on the European Organisation for Research and Treatment of Cancer (EORTC) website allowing users to estimate patients' survival outcomes. We tested this calculator against actual local survival data to validate its use in our patients. Prospectively collected clinical data were analysed on 105 consecutive patients receiving concurrent chemoradiotherapy following surgical treatment of GBM between December 2004 and February 2009. Using the EORTC online calculator, survival outcomes were generated for these patients and compared with their actual survival. The median overall survival for the entire cohort was 15.3 months (range 2.8-50.5 months), with 1-year and 2-year overall survival of 65.7% and 19%, respectively. This is in comparison to the median overall predictive survival of 21.3 months, with 1-year and 2-year survival of 95% and 39.5%, respectively. Case by case analysis also showed that the survival was overestimated in nearly 80% of patients. Subgroup analyses showed similar overestimation of patients' survival, except calculator Model 3 which utilised MGMT status. Use of the EORTC GBM prognostic calculator would have overestimated the survival of the majority of our patients with GBM. Uncertainty exists as to the cause of overestimation in the cohort although local socioeconomic factors might play a role. The different calculator models yielded different outcomes and the "best" predictor of survival for the cohort under study utilised the tumour MGMT status. We would strongly encourage similar local studies of validity testing prior to employing the online prognostic calculator for other population groups.

Fermi/GBM Results of Magnetars

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Kouveliotou, chryssa

2011-01-01

Magnetars are magnetically powered rotating neutron stars with extreme magnetic fields (over 10(exp 14) Gauss). They were discovered in the X- and gamma-rays where they predominantly emit their radiation. Very few sources (roughly 18) have been found since their discovery in 1987. NASA's Fermi Gamma-ray Space Telescope was launched June 11,2009; since then the Fermi Gamma-ray Burst Monitor (GBM) recorded emission from four magnetar sources. Two of these were brand new sources, SGR J0501 +4516, discovered with Swift and extensively monitored with Swift and GBM, SGR J0418+5729, discovered with GBM and the Interplanetary Network (IPN). A third was SGR Jl550-5418, a source originally classified as an Anomalous X-ray Pulsar (AXP IEI547.0-5408), but exhibiting a very prolific outburst with over 400 events recorded in January 2009. In my talk I will give a short history of magnetars and describe how this, once relatively esoteric field, has emerged as a link between several astrophysical areas including Gamma-Ray Bursts. Finally, I will describe the exciting new results of Fermi in this field and the current status of our knowledge of the magnetar population properties and magnetic fields.

Surprisal analysis of Glioblastoma Multiform (GBM) microRNA dynamics unveils tumor specific phenotype.

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Zadran, Sohila; Remacle, Francoise; Levine, Raphael

2014-01-01

Gliomablastoma multiform (GBM) is the most fatal form of all brain cancers in humans. Currently there are limited diagnostic tools for GBM detection. Here, we applied surprisal analysis, a theory grounded in thermodynamics, to unveil how biomolecule energetics, specifically a redistribution of free energy amongst microRNAs (miRNAs), results in a system deviating from a non-cancer state to the GBM cancer -specific phenotypic state. Utilizing global miRNA microarray expression data of normal and GBM patients tumors, surprisal analysis characterizes a miRNA system response capable of distinguishing GBM samples from normal tissue biopsy samples. We indicate that the miRNAs contributing to this system behavior is a disease phenotypic state specific to GBM and is therefore a unique GBM-specific thermodynamic signature. MiRNAs implicated in the regulation of stochastic signaling processes crucial in the hallmarks of human cancer, dominate this GBM-cancer phenotypic state. With this theory, we were able to distinguish with high fidelity GBM patients solely by monitoring the dynamics of miRNAs present in patients' biopsy samples. We anticipate that the GBM-specific thermodynamic signature will provide a critical translational tool in better characterizing cancer types and in the development of future therapeutics for GBM.

Survey of the effect of doxorubicin and flavonoid extract of white Morus alba leaf on apoptosis induction in a-172 GBM cell line.

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Dabili, Sheyda; Fallah, Soudabeh; Aein, Mojdeh; Vatannejad, Akram; Panahi, Ghodratollah; Fadaei, Reza; Moradi, Nariman; Shojaii, Asie

2018-02-20

In this study, the effect of doxorubicin, flavonoid extract of white Morus alba leaf (MFE) and a combination of doxorubicin and flavonoid extract on Bax and Bcl2 levels and caspase 3 activity of cancer A-172 GBM cell line was investigated. Bax/Bcl2 levels of treated A-172 GBM cell line with flavonoid extract of white mulberry leaf were estimated by ELISA methods. Caspase 3 activity of treated A-172 GBM cells was determined by calorimetric assay. The flow cytometry assessment was used to estimate the apoptosis percent of treated A-172 GBM cells. Treatment of A-172 GBM cells with MFE, doxorubicin and a combination of MFE and doxorubicin caused a significant decrease in Bcl2 level and an increase in Bax level. The apoptosis percent of treated cells were also elevated significantly. Present results suggest that concomitant use of herbal medicine and chemotherapy may be an effective alternative method for the treatment of cancers.

Differential Expression and Clinical Significance of Transforming Growth Factor-Beta Isoforms in GBM Tumors.

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Roy, Laurent-Olivier; Poirier, Marie-Belle; Fortin, David

2018-04-08

Glioblastoma (GBM) represents the most common and aggressive malignant primary brain tumors in adults. Response to standard treatment is transitory and the survival of clinical trial cohorts are little more than 14 months. GBM are characterized by excessive proliferation, invasiveness, and radio-/chemoresistance features; which are strongly upregulated by transforming growth factor-beta (TGF-β). We hypothesized that TGF-β gene expression could correlate with overall survival (OS) and serve as a prognostic biomarker. TGF-β₁ and -β₂ expression were analyzed by qPCR in 159 GBM tumor specimens. Kaplan-Meier and multivariate analyses were used to correlate expression with OS and progression-free survival (PFS). In GBM, TGF-β₁ and -β₂ levels were 33- and 11-fold higher respectively than in non-tumoral samples. Kaplan-Meier and multivariate analyses revealed that high to moderate expressions of TGF-β₁ significantly conferred a strikingly poorer OS and PFS in newly diagnosed patients. Interestingly, at relapse, neither isoforms had meaningful impact on clinical evolution. We demonstrate that TGF-β₁ is the dominant isoform in newly diagnosed GBM rather than the previously acknowledged TGF-β₂. We believe our study is the first to unveil a significant relationship between TGF-β₁ expression and OS or PFS in newly diagnosed GBM. TGF-β₁ could serve as a prognostic biomarker or target affecting treatment planning and patient follow-up.

Differential Expression and Clinical Significance of Transforming Growth Factor-Beta Isoforms in GBM Tumors

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Laurent-Olivier Roy

2018-04-01

Full Text Available Glioblastoma (GBM represents the most common and aggressive malignant primary brain tumors in adults. Response to standard treatment is transitory and the survival of clinical trial cohorts are little more than 14 months. GBM are characterized by excessive proliferation, invasiveness, and radio-/chemoresistance features; which are strongly upregulated by transforming growth factor-beta (TGF-β. We hypothesized that TGF-β gene expression could correlate with overall survival (OS and serve as a prognostic biomarker. TGF-β1 and -β2 expression were analyzed by qPCR in 159 GBM tumor specimens. Kaplan–Meier and multivariate analyses were used to correlate expression with OS and progression-free survival (PFS. In GBM, TGF-β1 and -β2 levels were 33- and 11-fold higher respectively than in non-tumoral samples. Kaplan–Meier and multivariate analyses revealed that high to moderate expressions of TGF-β1 significantly conferred a strikingly poorer OS and PFS in newly diagnosed patients. Interestingly, at relapse, neither isoforms had meaningful impact on clinical evolution. We demonstrate that TGF-β1 is the dominant isoform in newly diagnosed GBM rather than the previously acknowledged TGF-β2. We believe our study is the first to unveil a significant relationship between TGF-β1 expression and OS or PFS in newly diagnosed GBM. TGF-β1 could serve as a prognostic biomarker or target affecting treatment planning and patient follow-up.

Rituximab in anti-GBM disease: A retrospective study of 8 patients.

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Touzot, Maxime; Poisson, Johanne; Faguer, Stanislas; Ribes, David; Cohen, Pascal; Geffray, Loic; Anguel, Nadia; François, Helene; Karras, Alexandre; Cacoub, Patrice; Durrbach, Antoine; Saadoun, David

2015-06-01

Anti-glomerular basement membrane (GBM) disease is a rare autoantibody-mediated disorder presenting as rapidly progressive glomerulonephritis, and often with pulmonary hemorrhage. Antibody removal with plasmapheresis and immunosuppressive drugs are the cornerstones of the treatment. Data regarding the use of specific B-cell depleting therapy such as rituximab are lacking. We conducted a retrospective observational study of 8 patients with severe and/or refractory GBM disease that received rituximab therapy. Eight patients (2 men, 6 women) with a mean age of 26 ± 13.1 years old were included. Seven had severe renal involvement [median creatinin level was 282 μmol/l, range (65-423)] requiring high immunosuppressive or plasmapheresis dependent, and two had relapse of pulmonary hemorrhage including one with renal failure. Patients received an initial immunosuppressive treatment including steroid and cyclosphosphamide (n = 8) and plasmapheresis (n = 5). Except one late relapse, rituximab therapy was started within two months after diagnosis. All patients except one received 4 weekly dose of rituximab (375 mg(2)). Anti-GBM antibodies were still present in 6/8 patients, at rituximab initiation. Complete remission was observed in 7 out of 8 patients, mostly 3 months after rituximab therapy. After a mean follow-up of 25.6 months (range 4-93), patient and renal survival were 100% and 75% respectively, but rituximab use did not improve GFR. Anti-GBM antibodies remained negative for all patients during follow-up. Only one patient developed a severe bacterial infection but no opportunistic or viral infections were reported. Rituximab may represent an additional and/or alternative therapy in the induction treatment of anti-GBM disease. Copyright © 2015 Elsevier Ltd. All rights reserved.

Apparent diffusion coefficient in glioblastoma with PNET-like components, a GBM variant.

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Ali, Saad; Joseph, Nancy M; Perry, Arie; Barajas, Ramon F; Cha, Soonmee

2014-09-01

Glioblastoma (GBM) with primitive neuroectodermal tumor (PNET)-like (GBM-PNET) components is a rare variant of GBM. Recent studies describe PNET-like clinical behavior in these patients-with significantly increased propensity for CSF dissemination and a benefit of "PNET-like" chemotherapy. The imaging appearance of GBM-PNET is not well-described and given areas of marked cellularity in the PNET components one might expect significantly reduced diffusion on MRI. The purpose of this study is to quantitatively evaluate the diffusion characteristics in GBM-PNET and compare them with conventional GBMs. Nine patients with surgical specimens yielding GBM-PNET were identified from the UCSF Pathology files. MR images of these patients were reviewed retrospectively. DWI (diffusion-weighted imaging) sequences were analyzed with multiple regions of interests placed within the tumor, and ADC (apparent diffusion coefficient) values were measured. Results were compared to previously published ADC values in pathology-proven conventional GBM cases from our institution. Reduced ADC was seen in GBM-PNET (mean 581 × 10(-6) mm(2)/s, range 338-817) compared to previously published mean of 1,030 × 10(-6) mm(2)/s in the enhancing components of conventional GBMs. We report substantially reduced ADC values in GBM-PNETs compared to conventional GBMs. If demonstrated in a larger sample, when areas of marked reduced diffusion are seen in a suspected GBM, MRI may appropriately direct tissue sampling and can advocate a thorough search for PNET-like components on histopathology. These patients may have a higher chance of developing CSF dissemination and may benefit from "PNET-like" platinum-based chemotherapy.

Imp2 regulates GBM progression by activating IGF2/PI3K/Akt pathway.

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Mu, Qingchun; Wang, Lijun; Yu, Fengbo; Gao, Haijun; Lei, Ting; Li, Peiwen; Liu, Pengfei; Zheng, Xu; Hu, Xitong; Chen, Yong; Jiang, Zhenfeng; Sayari, Arash J; Shen, Jia; Huang, Haiyan

2015-01-01

Glioblastomas multiforme (GBM) are the most frequently occurring malignant brain cancers. Treatment for GBM consists of surgical resection and subsequent adjuvant radiation therapy and chemotherapy. Despite this, GBM patient survival is limited to 12-15 months, and researchers are continually trying to develop improved therapy options. Insulin-like growth factor 2 mRNA-binding protein 2 (Imp2) is known to be upregulated in many cancers and is known to regulate the signaling activity of insulin-like growth factor 2 (IGF2). However, relatively little is known about its role in malignant development of GBM. In this study, we first found Imp2 is upregulated in GBM tissues by using clinical samples and public database search. Studies with loss and gain of Imp2 expression in in vitro GBM cell culture system demonstrated the role of Imp2 in promoting GBM cell proliferation, migration, invasion and epithelial-to-mesenchymal transition (EMT). Additionally, our results show that Imp2 regulates the activity of IGF2, which further activates PI3K/Akt signaling, thereby to promote GBM malignancy. Inhibition of Imp2 was also found to sensitize GBM to temozolomide treatment. These observations add to the current knowledge of GBM biology, and may prove useful in development of more effective GBM therapy.

Impact of oligodendroglial component in glioblastoma (GBM-O): Is the outcome favourable than glioblastoma?

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Goda, Jayant S; Lewis, Shirley; Agarwal, Aditi; Epari, Sridhar; Churi, Shraddha; Padmavati, A; Gupta, Tejpal; Shetty, Prakash; Moiyadi, Aliasgar; Jalali, Rakesh

2015-08-01

Prognosis of patients with glioblastoma with oligodendroglial component (GBM-O) is not well defined. We report our experience of patients of GBM-O treated at our center. Between January 2007 and August 2013, out of 817 consecutive patients with glioblastoma (GBM), 74 patients with GBM-O were identified in our prospectively maintained database. An experienced neuropathologist revaluated the histopathology of all these 74 patients and the diagnosis of GBM-O was eventually confirmed in 57 patients. Patients were uniformly treated with maximal safe resection followed by focal radiotherapy with concurrent and adjuvant temozolamide (TMZ). At a median follow up of 16 months, median overall survival (OS) and progression free survival (PFS) of the entire cohort was 23 months and 13 months respectively. Near total excision was performed in 30/57 (52.6%). On univariate analysis, age GBM-O patients with a similarly treated cohort of 105 GBM patients during the same period revealed significantly better median OS in favour of GBM-O (p = 0.01). Our experience suggests patients with GBM-O have a more favourable clinical outcome as compared to GBM. Copyright © 2015 Elsevier B.V. All rights reserved.

Time Domain Astronomy with Fermi GBM in the Multi-messenger Era

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Wilson-Hodge, Colleen A.; Fermi GBM team, GBM-LIGO team

2018-01-01

As the Multi-Messenger era begins with detections of gravitational waves with LIGO/Virgo and neutrinos with IceCube, the Fermi Gamma-ray Burst Monitor (GBM) provides context observations of gamma-ray transients between 8 keV and 40 MeV. Fermi GBM has a wide field of view, high uptime, and both in-orbit triggering and high time resolution continuous data enabling offline searches for weaker transients. GBM detects numerous gamma-ray bursts (GRBs), soft gamma-ray repeaters, X-ray bursters, solar flares and terrestrial gamma-ray flashes. Longer timescale transients, predominantly in our galaxy so far, are detected using the Earth occultation technique and epoch-folding for periodic sources. The GBM team has developed two ground-based searches to enhance detections of faint transients, especially short GRBs. The targeted search uses the time and location of an event detected with another instrument to coherently search the GBM data, increasing the sensitivity to a transient. The untargeted search agnostically searches the GBM data for all directions and times to find weaker transients. This search finds about 80 short GRBs per year, adding to the 40 per year triggered on-orbit. With its large field of view, high duty cycle and increasingly sophisticated detection methods, Fermi GBM is expected to have a major role in the Multi-Messenger era.

Ficus carica latex prevents invasion through induction of let-7d expression in GBM cell lines.

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Tezcan, Gulcin; Tunca, Berrin; Bekar, Ahmet; Yalcin, Murat; Sahin, Saliha; Budak, Ferah; Cecener, Gulsah; Egeli, Unal; Demir, Cevdet; Guvenc, Gokcen; Yilmaz, Gozde; Erkan, Leman Gizem; Malyer, Hulusi; Taskapilioglu, Mevlut Ozgur; Evrensel, Turkkan; Bilir, Ayhan

2015-03-01

Glioblastoma multiforme (GBM) is one of the deadliest human malignancies. A cure for GBM remains elusive, and the overall survival time is less than 1 year. Thus, the development of more efficient therapeutic approaches for the treatment of these patients is required. Induction of tumor cell death by certain phytochemicals derived from medicinal herbs and dietary plants has become a new frontier for cancer therapy research. Although the cancer suppressive effect of Ficus carica (fig) latex (FCL) has been determined in a few cancer types, the effect of this latex on GBM tumors has not been investigated. Therefore, in the current study, the anti-proliferative activity of FCL and the effect of the FCL-temozolomide (TMZ) combination were tested in the T98G, U-138 MG, and U-87 MG GBM cell lines using the WST-1 assay. The mechanism of cell death was analyzed using Annexin-V/FITC and TUNEL assays, and the effect of FCL on invasion was tested using the chick chorioallantoic membrane assay. To determine the effect of FCL on GBM progression, the expression levels of 40 GBM associated miRNAs were analyzed in T98G cells using RT-qPCR. According to the obtained data, FCL causes cell death in GBM cells with different responses to TMZ, and this effect is synergistically increased in combination with TMZ. In addition, the current study is the first to demonstrate the effect of FCL on modulation of let-7d expression, which may be an important underlying mechanism of the anti-invasive effect of this extract.

Predicting Outcome in Patients with Anti-GBM Glomerulonephritis.

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van Daalen, Emma E; Jennette, J Charles; McAdoo, Stephen P; Pusey, Charles D; Alba, Marco A; Poulton, Caroline J; Wolterbeek, Ron; Nguyen, Tri Q; Goldschmeding, Roel; Alchi, Bassam; Griffiths, Meryl; de Zoysa, Janak R; Vincent, Beula; Bruijn, Jan A; Bajema, Ingeborg M

2018-01-06

Large studies on long-term kidney outcome in patients with anti-glomerular basement membrane (anti-GBM) GN are lacking. This study aimed to identify clinical and histopathologic parameters that predict kidney outcome in these patients. This retrospective analysis included a total of 123 patients with anti-GBM GN between 1986 and 2015 from six centers worldwide. Their kidney biopsy samples were classified according to the histopathologic classification for ANCA-associated GN. Clinical data such as details of treatment were retrieved from clinical records. The primary outcome parameter was the occurrence of ESRD. Kidney survival was analyzed using the log-rank test and Cox regression analyses. The 5-year kidney survival rate was 34%, with an improved rate observed among patients diagnosed after 2007 ( P =0.01). In patients with anti-GBM GN, histopathologic class and kidney survival were associated ( P GBM GN. Kidney outcome has improved during recent years; the success rate doubled after 2007. This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2017_11_21_CJASNPodcast_18_1_v.mp3. Copyright © 2018 by the American Society of Nephrology.

Does age matter? Sexual event-level analysis of age-disparate sexual partners among gay, bisexual and other men who have sex with men (GBM) in Vancouver, Canada.

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Closson, K; Lachowsky, N J; Cui, Z; Shurgold, S; Sereda, P; Rich, A; Moore, D M; Roth, E A; Hogg, R S

2017-08-01

To determine factors associated with age-disparate sexual partners among Vancouver gay, bisexual and other men who have sex with men (GBM). Sexually active GBM aged ≥16 years were recruited from February 2012 to February 2014. Participants self-completed a questionnaire on demographics, attitudes and sexual behaviour and substance use at last sexual event with five most recent partners. Two generalised linear mixed models identified factors associated with: (1) 'same-age' (referent), 'younger' or 'much-younger' and (2) 'same-age' (referent), 'older' or 'much-older' partners. Statistical interactions between age and HIV status were tested. Participants (n=719) were predominantly gay (85.1%), White (75.0%), HIV-negative/unknown status (72.9%) with median age of 33 years (Q1,Q3: 26,47). A minority of sexual events were reported with much-older/much-younger partners (13.7%). In the multivariable models, GBM reporting older partners were more likely to be Asian or Latino, have greater Escape Motivation scores, report their partner used erectile dysfunction drugs (EDDs) and have received something for sex; compared with condom-protected insertive anal sex, participants with older partners were more likely to report condomless insertive anal sex with a serodiscordant or unknown status partner or no insertive anal sex. GBM reporting older partners were less likely to be bisexual-identified, have given something for sex and report event-level alcohol and EDD use. GBM reporting younger partners were more likely to have annual incomes >$30 000 and have met their partner online. As per significant statistical interactions, age-disparate relations were more common for younger HIV-positive and older HIV-negative GBM. Differences among age-disparate partners highlight important targets for health promotion and future research. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Targeted Proteomics to Assess the Response to Anti-Angiogenic Treatment in Human Glioblastoma (GBM).

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Demeure, Kevin; Fack, Fred; Duriez, Elodie; Tiemann, Katja; Bernard, Amandine; Golebiewska, Anna; Bougnaud, Sébastien; Bjerkvig, Rolf; Domon, Bruno; Niclou, Simone P

2016-02-01

Glioblastoma (GBM) is a highly aggressive primary brain tumor with dismal outcome for affected patients. Because of the significant neo-angiogenesis exhibited by GBMs, anti-angiogenic therapies have been intensively evaluated during the past years. Recent clinical studies were however disappointing, although a subpopulation of patients may benefit from such treatment. We have previously shown that anti-angiogenic targeting in GBM increases hypoxia and leads to a metabolic adaptation toward glycolysis, suggesting that combination treatments also targeting the glycolytic phenotype may be effective in GBM patients. The aim of this study was to identify marker proteins that are altered by treatment and may serve as a short term readout of anti-angiogenic therapy. Ultimately such proteins could be tested as markers of efficacy able to identify patient subpopulations responsive to the treatment. We applied a proteomics approach based on selected reaction monitoring (SRM) to precisely quantify targeted protein candidates, selected from pathways related to metabolism, apoptosis and angiogenesis. The workflow was developed in the context of patient-derived intracranial GBM xenografts developed in rodents and ensured the specific identification of human tumor versus rodent stroma-derived proteins. Quality control experiments were applied to assess sample heterogeneity and reproducibility of SRM assays at different levels. The data demonstrate that tumor specific proteins can be precisely quantified within complex biological samples, reliably identifying small concentration differences induced by the treatment. In line with previous work, we identified decreased levels of TCA cycle enzymes, including isocitrate dehydrogenase, whereas malectin, calnexin, and lactate dehydrogenase A were augmented after treatment. We propose the most responsive proteins of our subset as potential novel biomarkers to assess treatment response after anti-angiogenic therapy that warrant future

Differential role of EGF and BFGF in human GBM-TIC proliferation: relationship to EGFR-tyrosine kinase inhibitor sensibility.

Science.gov (United States)

Bajetto, A; Porcile, C; Pattarozzi, A; Scotti, L; Aceto, A; Daga, A; Barbieri, F; Florio, T

2013-01-01

Glioblastoma multiforme (GBM) is among the most devastating human tumors being rapidly fatal despite aggressive surgery, radiation and chemotherapies. It is characterized by extensive dissemination of tumor cells within the brain that hinders complete surgical resection. GBM tumor initiating-cells (TICs) are a rare subpopulation of cells responsible for tumor development, growth, invasiveness and recurrence after chemotherapy. TICs from human GBM can be selected in vitro using the same conditions permissive for the growth of normal neural cells, of which share some features including marker expression, self-renewal capacity, long-term proliferation, and ability to differentiate into neuronal and glial cells. EGFR overexpression and its constitutive activation is one of the most important signaling alteration identified in GBM, and its pharmacological targeting represents an attractive therapeutic goal. We previously demonstrated that human GBM TICs have different sensitivity to the EGFR kinase inhibitors erlotinib and gefitinib, depending on the differential modulation of downstream signaling cascades. In this work we investigated the mechanisms of resistance to erlotinib in two human GBM TIC cultures, analyzing EGF and bFGF individual contribution to proliferation, clonogenicity, and migration. We demonstrated the presence of a small cell subpopulation whose proliferation is supported by EGF and a larger one mainly dependent on bFGF. Thus, insensitivity to EGFR kinase inhibitors as far as TIC proliferation results from a predominant FGFR activation that hides the inhibitory effects induced on EGFR signaling. Conversely, EGF and bFGF induced cell migration with similar efficacy. In addition, unlike neural stem/progenitors cells, the removal of chondroitin sulphate proteoglycans from cell surface was unable to discern EGF- and bFGF-dependent subpopulations in GBM TICs.

TCGA Workshop: Genomics and Biology of Glioblastoma Multiforme (GBM) - TCGA

Science.gov (United States)

The National Cancer Institute (NCI) and National Human Genome Research Institute (NHGRI) held a workshop entitled, “Genomics and Biology of Glioblastoma Multiforme (GBM),” to review the initial GBM data from the TCGA pilot project.

SOX4 inhibits GBM cell growth and induces G0/G1 cell cycle arrest through Akt-p53 axis.

Science.gov (United States)

Zhang, Jing; Jiang, Huawei; Shao, Jiaofang; Mao, Ruifang; Liu, Jie; Ma, Yingying; Fang, Xuefeng; Zhao, Na; Zheng, Shu; Lin, Biaoyang

2014-11-01

SOX4 is a transcription factor required for tissue development and differentiation in vertebrates. Overexpression of SOX4 has been reported in many cancers including glioblastoma multiforme (GBM), however, the underlying mechanism of actions has not been studied. In this study, we investigated the role of SOX4 in GBM. Kaplan-Meier analysis was performed to assess the association between SOX4 expression levels and survival times in primary GBM samples. Cre/lox P system was used to generate gain or loss of SOX4 in GBM cells, and microarray analysis uncovered the regulation network of SOX4 in GBM cells. High SOX4 expression was significantly associated with good prognosis of primary GBMs. SOX4 inhibited the growth of GBM cell line LN229, A172G and U87MG, partly via the activation of p53-p21 signaling and down-regulation of phosphorylated AKT1. Gene expression profiling and subsequent gene ontology analysis showed that SOX4 influenced several key pathways including the Wnt/ beta-catenin and TGF-beta signaling pathways. Our study found that SOX4 acts as a tumor suppressor in GBM cells by induce cell cycle arrest and inhibiting cell growth.

Visualizing molecular profiles of glioblastoma with GBM-BioDP.

Directory of Open Access Journals (Sweden)

Orieta Celiku

Full Text Available Validation of clinical biomarkers and response to therapy is a challenging topic in cancer research. An important source of information for virtual validation is the datasets generated from multi-center cancer research projects such as The Cancer Genome Atlas project (TCGA. These data enable investigation of genetic and epigenetic changes responsible for cancer onset and progression, response to cancer therapies, and discovery of the molecular profiles of various cancers. However, these analyses often require bulk download of data and substantial bioinformatics expertise, which can be intimidating for investigators. Here, we report on the development of a new resource available to scientists: a data base called Glioblastoma Bio Discovery Portal (GBM-BioDP. GBM-BioDP is a free web-accessible resource that hosts a subset of the glioblastoma TCGA data and enables an intuitive query and interactive display of the resultant data. This resource provides visualization tools for the exploration of gene, miRNA, and protein expression, differential expression within the subtypes of GBM, and potential associations with clinical outcome, which are useful for virtual biological validation. The tool may also enable generation of hypotheses on how therapies impact GBM molecular profiles, which can help in personalization of treatment for optimal outcome. The resource can be accessed freely at http://gbm-biodp.nci.nih.gov (a tutorial is included.

Quantitative Magnetization Transfer in Monitoring Glioblastoma (GBM) Response to Therapy.

Science.gov (United States)

Mehrabian, Hatef; Myrehaug, Sten; Soliman, Hany; Sahgal, Arjun; Stanisz, Greg J

2018-02-06

Quantitative magnetization transfer (qMT) was used as a biomarker to monitor glioblastoma (GBM) response to chemo-radiation and identify the earliest time-point qMT could differentiate progressors from non-progressors. Nineteen GBM patients were recruited and MRI-scanned before (Day 0 ), two weeks (Day 14 ), and four weeks (Day 28 ) into the treatment, and one month after the end of the treatment (Day 70 ). Comprehensive qMT data was acquired, and a two-pool MT model was fit to the data. Response was determined at 3-8 months following the end of chemo-radiation. The amount of magnetization transfer ([Formula: see text]) was significantly lower in GBM compared to normal appearing white matter (p GBM are more sensitive to treatment effects compared to clinically used metrics. qMT could assess tumor aggressiveness and identify early progressors even before the treatment. Changes in qMT parameters within the first 14 days of the treatment were capable of separating early progressors from non-progressors, making qMT a promising biomarker to guide adaptive radiotherapy for GBM.

The Second Fermi GBM Gamma-Ray Burst Catalog: The First Four Years

NARCIS (Netherlands)

von Kienlin, A.; Meegan, C.A.; Paciesas, W.S.; Bhat, P.N.; Bissaldi, E.; Briggs, M.S.; Burgess, J.M.; Byrne, D.; Chaplin, V.; Cleveland, W.; Connaughton, V.; Collazzi, A.C.; Fitzpatrick, G.; Foley, S.; Gibby, M.; Giles, M.; Goldstein, A.; Greiner, J.; Gruber, D.; Guiriec, S.; van der Horst, A.J.; Kouveliotou, C.; Layden, E.; McBreen, S.; McGlynn, S.; Pelassa, V.; Preece, R.D.; Rau, A.; Tierney, D.; Wilson-Hodge, C.A.; Xiong, S.; Younes, G.; Yu, H-F.

2014-01-01

This is the second of a series of catalogs of gamma-ray bursts (GRBs) observed with the Fermi Gamma-ray Burst Monitor (GBM). It extends the first two-year catalog by two more years, resulting in an overall list of 953 GBM triggered GRBs. The intention of the GBM GRB catalog is to provide information

Downregulation of ZMYND11 induced by miR-196a-5p promotes the progression and growth of GBM.

Science.gov (United States)

Yang, Ji-Peng; Yang, Jian-Kai; Li, Chen; Cui, Zhi-Qiang; Liu, Hong-Jiang; Sun, Xiao-Feng; Geng, Shao-Mei; Lu, Sheng-Kui; Song, Jian; Guo, Cheng-Yong; Jiao, Bao-Hua

2017-12-16

ZMYND11 (zinc finger MYND-type containing 11) has been widely regarded to be involved in a variety of cancers as a potential suppressor. However, the biological role and mechanism of ZMYND11 in glioblastoma multiform (GBM) remain unknown. In this study, we found that ZMYND11 expression was remarkably decreased in GBM tissues from 20 cases and cell line (U87) compared to normal brain tissue from 10 cases (P GBM tissue and U87 cells by changing the expression level of miR-196a-5p with lentivirus and plasmid vector. Furthermore, we demonstrated that decreased ZMYND11 could reverse suppressive effect of downregulated miR-196a-5p on U87 by rescue experiment. Taken together, ZMYND11 was demonstrated to be a potential and extremely promising suppressor of GBM, while miRNA-196a-5p was quite an important target of treatment of GBM. Copyright © 2017 Elsevier Inc. All rights reserved.

miR-139-5p suppresses cancer cell migration and invasion through targeting ZEB1 and ZEB2 in GBM.

Science.gov (United States)

Yue, Sihai; Wang, Lihua; Zhang, Hui; Min, Youhui; Lou, Yongli; Sun, Hongshan; Jiang, Yu; Zhang, Wenjin; Liang, Aming; Guo, Yongkun; Chen, Ping; Lv, Guowei; Wang, Liuxiang; Zong, Qinghua; Li, Yong

2015-09-01

Invasion and migration of glioblastoma multiforme (GBM) is a multistep process and an important phenotype that causes this disease to invade surrounding tissues in the brain. Recent studies have highlighted that miRNAs play a pivotal role in controlling GBM cell plasticity. In this report, we used wound healing and transwell assays to identify a novel role of miR-139-5p in inhibition of GBM cell migration and invasion. Bioinformatics coupled with luciferase and Western blot assays also revealed that miR-139-5p inhibited expression of ZEB1 and ZEB2, which are master regulators of tumor metastasis. MiR-139-5p specifically interacts with the 3'-UTR regions of ZEB1 and ZEB2, attenuating their expression in GBM cells. To corroborate this finding, we rescued ZEB1 and ZEB2 expression and found partial but significant increases in miR-139-5p-suppressed invasion of GBM cells. The biological relevance of our study was validated by analyzing levels of miR-139-5p in GBM tissue. We found that its expression significantly downregulated compared to normal tissue and shorter overall survival rates in patients with lower miR-139-5p expression. These results confirm that miR-139-5p suppresses GBM migration and invasion and highlight its potential as a biomarker and therapeutic target for treating GBM.

All-Sky Monitoring of Variable Sources with Fermi GBM

Science.gov (United States)

Wilson-Hodge, Colleen A.; Cherry, Michael L.; Case, Gary L.; Camero-Arranz, Ascension; Chaplin, Vandiver; Connaughton, Valerie; Finger, Mark H.; Jenke, Pater; Rodi, James C.; Baumgartner, Wayne H.;

Fully automatic GBM segmentation in the TCGA-GBM dataset: Prognosis and correlation with VASARI features.

Science.gov (United States)

Rios Velazquez, Emmanuel; Meier, Raphael; Dunn, William D; Alexander, Brian; Wiest, Roland; Bauer, Stefan; Gutman, David A; Reyes, Mauricio; Aerts, Hugo J W L

2015-11-18

Reproducible definition and quantification of imaging biomarkers is essential. We evaluated a fully automatic MR-based segmentation method by comparing it to manually defined sub-volumes by experienced radiologists in the TCGA-GBM dataset, in terms of sub-volume prognosis and association with VASARI features. MRI sets of 109 GBM patients were downloaded from the Cancer Imaging archive. GBM sub-compartments were defined manually and automatically using the Brain Tumor Image Analysis (BraTumIA). Spearman's correlation was used to evaluate the agreement with VASARI features. Prognostic significance was assessed using the C-index. Auto-segmented sub-volumes showed moderate to high agreement with manually delineated volumes (range (r): 0.4 - 0.86). Also, the auto and manual volumes showed similar correlation with VASARI features (auto r = 0.35, 0.43 and 0.36; manual r = 0.17, 0.67, 0.41, for contrast-enhancing, necrosis and edema, respectively). The auto-segmented contrast-enhancing volume and post-contrast abnormal volume showed the highest AUC (0.66, CI: 0.55-0.77 and 0.65, CI: 0.54-0.76), comparable to manually defined volumes (0.64, CI: 0.53-0.75 and 0.63, CI: 0.52-0.74, respectively). BraTumIA and manual tumor sub-compartments showed comparable performance in terms of prognosis and correlation with VASARI features. This method can enable more reproducible definition and quantification of imaging based biomarkers and has potential in high-throughput medical imaging research.

In search of druggable targets for GBM amino acid metabolism

NARCIS (Netherlands)

Panosyan, Eduard H.; Lin, Henry J.; Koster, Jan; Lasky, Joseph L.

2017-01-01

Background: Amino acid (AA) pathways may contain druggable targets for glioblastoma (GBM). Literature reviews and GBM database (http://r2.amc.nl) analyses were carried out to screen for such targets among 95 AA related enzymes. Methods: First, we identified the genes that were differentially

Search for Gravitational Wave Counterparts with Fermi GBM

Science.gov (United States)

Hui, C. M.

2017-01-01

The progenitor of short gamma-ray bursts (GRBs) is believed to be the merger of two compact objects. This type of events will also produce gravitational waves. Since the gravitational waves discovery by LIGO, the search for a joint detection with an electromagnetic counterpart has been ongoing. Fermi GBM detects approximately 40 short GRBs per year, and we have been expanding our search looking for faint events in the GBM data that did not trigger onboard.

THE FIVE YEAR FERMI/GBM MAGNETAR BURST CATALOG

Energy Technology Data Exchange (ETDEWEB)

Collazzi, A. C. [SciTec, Inc., 100 Wall Street, Princeton, NJ 08540 (United States); Kouveliotou, C.; Horst, A. J. van der; Younes, G. A. [Department of Physics, The George Washington University, 725 21st Street NW, Washington, DC 20052 (United States); Kaneko, Y.; Göğüş, E. [Sabancı University, Orhanlı-Tuzla, İstanbul 34956 (Turkey); Lin, L. [François Arago Centre, APC, 10 rue Alice Domon et Léonie Duquet, F-75205 Paris (France); Granot, J. [Department of Natural Sciences, The Open University of Israel, 1 University Road, P.O. Box 808, Raanana 43537 (Israel); Finger, M. H. [Universities Space Research Association, NSSTC, 320 Sparkman Drive, Huntsville, AL 35805 (United States); Chaplin, V. L. [School of Medicine, Vanderbilt University, 1161 21st Avenue S, Nashville, TN 37232 (United States); Huppenkothen, D. [Center for Data Science, New York University, 726 Broadway, 7th Floor, New York, NY 10003 (United States); Watts, A. L. [Anton Pannekoek Institute, University of Amsterdam, Postbus 94249, 1090 GE Amsterdam (Netherlands); Kienlin, A. von [Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching (Germany); Baring, M. G. [Department of Physics and Astronomy, Rice University, MS-108, P.O. Box 1892, Houston, TX 77251 (United States); Gruber, D. [Planetarium Südtirol, Gummer 5, I-39053 Karneid (Italy); Bhat, P. N. [CSPAR, University of Alabama in Huntsville, 320 Sparkman Drive, Huntsville, AL 35899 (United States); Gibby, M. H., E-mail: acollazzi@scitec.com [Jacobs Technology, Inc., Huntsville, AL (United States); and others

2015-05-15

Since launch in 2008, the Fermi Gamma-ray Burst Monitor (GBM) has detected many hundreds of bursts from magnetar sources. While the vast majority of these bursts have been attributed to several known magnetars, there is also a small sample of magnetar-like bursts of unknown origin. Here, we present the Fermi/GBM magnetar catalog, providing the results of the temporal and spectral analyses of 440 magnetar bursts with high temporal and spectral resolution. This catalog covers the first five years of GBM magnetar observations, from 2008 July to 2013 June. We provide durations, spectral parameters for various models, fluences, and peak fluxes for all the bursts, as well as a detailed temporal analysis for SGR J1550–5418 bursts. Finally, we suggest that some of the bursts of unknown origin are associated with the newly discovered magnetar 3XMM J185246.6+0033.7.

40 CFR 180.1097 - GBM-ROPE; exemption from the requirement of a tolerance.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 23 2010-07-01 2010-07-01 false GBM-ROPE; exemption from the... Exemptions From Tolerances § 180.1097 GBM-ROPE; exemption from the requirement of a tolerance. The grape berry moth pheromone (GBM-ROPE) containing the active ingredients (Z)-9-dedecenyl acetate and (Z)-11...

Adaptive Global Innovative Learning Environment for Glioblastoma: GBM AGILE.

Science.gov (United States)

Alexander, Brian M; Ba, Sujuan; Berger, Mitchel S; Berry, Donald A; Cavenee, Webster K; Chang, Susan M; Cloughesy, Timothy F; Jiang, Tao; Khasraw, Mustafa; Li, Wenbin; Mittman, Robert; Poste, George H; Wen, Patrick Y; Yung, W K Alfred; Barker, Anna D

2018-02-15

Glioblastoma (GBM) is a deadly disease with few effective therapies. Although much has been learned about the molecular characteristics of the disease, this knowledge has not been translated into clinical improvements for patients. At the same time, many new therapies are being developed. Many of these therapies have potential biomarkers to identify responders. The result is an enormous amount of testable clinical questions that must be answered efficiently. The GBM Adaptive Global Innovative Learning Environment (GBM AGILE) is a novel, multi-arm, platform trial designed to address these challenges. It is the result of the collective work of over 130 oncologists, statisticians, pathologists, neurosurgeons, imagers, and translational and basic scientists from around the world. GBM AGILE is composed of two stages. The first stage is a Bayesian adaptively randomized screening stage to identify effective therapies based on impact on overall survival compared with a common control. This stage also finds the population in which the therapy shows the most promise based on clinical indication and biomarker status. Highly effective therapies transition in an inferentially seamless manner in the identified population to a second confirmatory stage. The second stage uses fixed randomization to confirm the findings from the first stage to support registration. Therapeutic arms with biomarkers may be added to the trial over time, while others complete testing. The design of GBM AGILE enables rapid clinical testing of new therapies and biomarkers to speed highly effective therapies to clinical practice. Clin Cancer Res; 24(4); 737-43. ©2017 AACR . ©2017 American Association for Cancer Research.

Size of shell universe in light of Fermi GBM transient associated with GW150914

Directory of Open Access Journals (Sweden)

Merab Gogberashvili

2016-12-01

Full Text Available The possible burst occurred in location and temporal consistence with gravitational wave event GW150914, as reported by Fermi GBM, offers a new way of constraining models with extra dimensions. Using the time delay in arrival of the gamma ray transient observed by Fermi Gamma-ray Burst Monitor (GMB relative to the gravitational waves event triggered by the LIGO detectors we investigate the size of the spherical brane-universe expanding in multi-dimensional space–time. It is shown that a joint observation of gravitational waves in association with gamma ray burst can provide a very stringent bound on the spatial curvature of the brain.

Size of shell universe in light of Fermi GBM transient associated with GW150914

Energy Technology Data Exchange (ETDEWEB)

Gogberashvili, Merab, E-mail: gogber@gmail.com [Department of Exact and Natural Sciences, Javakhishvili Tbilisi State University, Tbilisi 0179, Georgia (United States); Department of High Energy Physics, Andronikashvili Institute of Physics, Tbilisi 0177, Georgia (United States); Sakharov, Alexander S., E-mail: Alexandre.Sakharov@cern.ch [Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); Physics Department, Manhattan College, 4513 Manhattan College Parkway, Riverdale, NY 10471 (United States); Experimental Physics Department, CERN, CH-1211 Genève 23 (Switzerland); Sarkisyan-Grinbaum, Edward K., E-mail: sedward@cern.ch [Experimental Physics Department, CERN, CH-1211 Genève 23 (Switzerland); Department of Physics, The University of Texas at Arlington, 502 Yates Street, Box 19059, Arlington, TX 76019 (United States)

2016-12-10

The possible burst occurred in location and temporal consistence with gravitational wave event GW150914, as reported by Fermi GBM, offers a new way of constraining models with extra dimensions. Using the time delay in arrival of the gamma ray transient observed by Fermi Gamma-ray Burst Monitor (GMB) relative to the gravitational waves event triggered by the LIGO detectors we investigate the size of the spherical brane-universe expanding in multi-dimensional space–time. It is shown that a joint observation of gravitational waves in association with gamma ray burst can provide a very stringent bound on the spatial curvature of the brain.

Validation of an imageable surgical resection animal model of Glioblastoma (GBM).

Science.gov (United States)

Sweeney, Kieron J; Jarzabek, Monika A; Dicker, Patrick; O'Brien, Donncha F; Callanan, John J; Byrne, Annette T; Prehn, Jochen H M

2014-08-15

Glioblastoma (GBM) is the most common and malignant primary brain tumour having a median survival of just 12-18 months following standard therapy protocols. Local recurrence, post-resection and adjuvant therapy occurs in most cases. U87MG-luc2-bearing GBM xenografts underwent 4.5mm craniectomy and tumour resection using microsurgical techniques. The cranial defect was repaired using a novel modified cranial window technique consisting of a circular microscope coverslip held in place with glue. Immediate post-operative bioluminescence imaging (BLI) revealed a gross total resection rate of 75%. At censor point 4 weeks post-resection, Kaplan-Meier survival analysis revealed 100% survival in the surgical group compared to 0% in the non-surgical cohort (p=0.01). No neurological defects or infections in the surgical group were observed. GBM recurrence was reliably imaged using facile non-invasive optical bioluminescence (BLI) imaging with recurrence observed at week 4. For the first time, we have used a novel cranial defect repair method to extend and improve intracranial surgical resection methods for application in translational GBM rodent disease models. Combining BLI and the cranial window technique described herein facilitates non-invasive serial imaging follow-up. Within the current context we have developed a robust methodology for establishing a clinically relevant imageable GBM surgical resection model that appropriately mimics GBM recurrence post resection in patients. Copyright © 2014 Elsevier B.V. All rights reserved.

Radiation and Background Levels in a CLIC Detector due to Beam-Beam Effects Optimisation of Detector Geometries and Technologies

CERN Document Server

Sailer, André; Lohse, Thomas

2013-01-10

The high charge density---due to small beam sizes---and the high energy of the proposed CLIC concept for a linear electron--positron collider with a centre-of-mass energy of up to 3~TeV lead to the production of a large number of particles through beam-beam interactions at the interaction point during every bunch crossing (BX). A large fraction of these particles safely leaves the detector. A still significant amount of energy will be deposited in the forward region nonetheless, which will produce secondary particles able to cause background in the detector. Furthermore, some particles will be created with large polar angles and directly cause background in the tracking detectors and calorimeters. The main sources of background in the detector, either directly or indirectly, are the incoherent $mathrm{e}^{+}mathrm{e}^{-}$ pairs and the particles from $gammagamma ightarrow$ hadron events. The background and radiation levels in the detector have to be estimated, to study if a detector is feasible, that can han...

Reference handbook: Level detectors

International Nuclear Information System (INIS)

1990-01-01

The purpose of this handbook is to provide Rocky Flats personnel with the information necessary to understand level measurement and detection. Upon completion of this handbook you should be able to do the following: List three reasons for measuring level. Describe the basic operating principles of the sight glass. Demonstrate proper techniques for reading a sight glass. Describe the basic operating principles of a float level detector. Describe the basic operating principles of a bubbler level indicating system. Explain the differences between a wet and dry reference leg indicating system, and describe how each functions. This handbook is designed for use by experienced Rocky Flats operators to reinforce and improve their current knowledge level, and by entry-level operators to ensure that they possess a minimum level of fundamental knowledge. Level Detectors is applicable to many job classifications and can be used as a reference for classroom work or for self-study. Although this reference handbook is by no means all-encompassing, you will gain enough information about this subject area to assist you in contributing to the safe operation of Rocky Flats Plant

Tumor associated CD70 expression is involved in promoting tumor migration and macrophage infiltration in GBM.

Science.gov (United States)

Ge, Haitao; Mu, Luyan; Jin, Linchun; Yang, Changlin; Chang, Yifan Emily; Long, Yu; DeLeon, Gabriel; Deleyrolle, Loic; Mitchell, Duane A; Kubilis, Paul S; Lu, Dunyue; Qi, Jiping; Gu, Yunhe; Lin, Zhiguo; Huang, Jianping

2017-10-01

Tumor migration/metastasis and immunosuppression are major obstacles in effective cancer therapy. Incidentally, these 2 hurdles usually coexist inside tumors, therefore making therapy significantly more complicated, as both oncogenic mechanisms must be addressed for successful therapeutic intervention. Our recent report highlights that the tumor expression of a TNF family member, CD70, is correlated with poor survival for primary gliomas. In this study, we investigated how CD70 expression by GBM affects the characteristics of tumor cells and the tumor microenvironment. We found that the ablation of CD70 in primary GBM decreased CD44 and SOX2 gene expression, and inhibited tumor migration, growth and the ability to attract monocyte-derived M2 macrophages in vitro. In the tumor microenvironment, CD70 was associated with immune cell infiltrates, such as T cells; myeloid-derived suppressor cells; and monocytes/macrophages based on the RNA-sequencing profile. The CD163+ macrophages were far more abundant than T cells were. This overwhelming level of macrophages was identified only in GBM and not in low-grade gliomas and normal brain specimens, implying their tumor association. CD70 was detected only on tumor cells, not on macrophages, and was highly correlated with CD163 gene expression in primary GBM. Additionally, the co-expression of the CD70 and CD163 genes was found to correlate with decreased survival for patients with primary GBM. Together, these data suggest that CD70 expression is involved in promoting tumor aggressiveness and immunosuppression via tumor-associated macrophage recruitment/activation. Our current efforts to target this molecule using chimeric antigen receptor T cells hold great potential for treating patients with GBM. © 2017 UICC.

The Fermi GBM and LAT follow-up of GW150914

Directory of Open Access Journals (Sweden)

Bissaldi E.

2017-01-01

Here we present observations by the Fermi Gamma-Ray BurstMonitor (GBM [1] and by the Large Area Telescope (LAT [2] of the LIGO Gravitational Wave event GW150914, which has been associated to the merger of two stellar-mass BHs. We report the presence of a weak transient event in GBM data, close in time to the LIGO one. We discuss the characteristics of this GBM transient, which are consistent with a weak short GRB arriving at a large angle to the direction in which Fermi was pointing. Furthermore, we report LAT upper limits (ULs for GW150914, and we present the strategy for follow-up observations of GW events with the LAT.

Identification of a novel set of genes reflecting different in vivo invasive patterns of human GBM cells

International Nuclear Information System (INIS)

Monticone, Massimiliano; Giaretti, Walter; Pfeffer, Ulrich; Daga, Antonio; Candiani, Simona; Romeo, Francesco; Mirisola, Valentina; Viaggi, Silvia; Melloni, Ilaria; Pedemonte, Simona; Zona, Gianluigi

2012-01-01

Most patients affected by Glioblastoma multiforme (GBM, grade IV glioma) experience a recurrence of the disease because of the spreading of tumor cells beyond surgical boundaries. Unveiling mechanisms causing this process is a logic goal to impair the killing capacity of GBM cells by molecular targeting. We noticed that our long-term GBM cultures, established from different patients, may display two categories/types of growth behavior in an orthotopic xenograft model: expansion of the tumor mass and formation of tumor branches/nodules (nodular like, NL-type) or highly diffuse single tumor cell infiltration (HD-type). We determined by DNA microarrays the gene expression profiles of three NL-type and three HD-type long-term GBM cultures. Subsequently, individual genes with different expression levels between the two groups were identified using Significance Analysis of Microarrays (SAM). Real time RT-PCR, immunofluorescence and immunoblot analyses, were performed for a selected subgroup of regulated gene products to confirm the results obtained by the expression analysis. Here, we report the identification of a set of 34 differentially expressed genes in the two types of GBM cultures. Twenty-three of these genes encode for proteins localized to the plasma membrane and 9 of these for proteins are involved in the process of cell adhesion. This study suggests the participation in the diffuse infiltrative/invasive process of GBM cells within the CNS of a novel set of genes coding for membrane-associated proteins, which should be thus susceptible to an inhibition strategy by specific targeting. Massimiliano Monticone and Antonio Daga contributed equally to this work

Identification of a novel set of genes reflecting different in vivo invasive patterns of human GBM cells.

Science.gov (United States)

Monticone, Massimiliano; Daga, Antonio; Candiani, Simona; Romeo, Francesco; Mirisola, Valentina; Viaggi, Silvia; Melloni, Ilaria; Pedemonte, Simona; Zona, Gianluigi; Giaretti, Walter; Pfeffer, Ulrich; Castagnola, Patrizio

2012-08-17

Most patients affected by Glioblastoma multiforme (GBM, grade IV glioma) experience a recurrence of the disease because of the spreading of tumor cells beyond surgical boundaries. Unveiling mechanisms causing this process is a logic goal to impair the killing capacity of GBM cells by molecular targeting.We noticed that our long-term GBM cultures, established from different patients, may display two categories/types of growth behavior in an orthotopic xenograft model: expansion of the tumor mass and formation of tumor branches/nodules (nodular like, NL-type) or highly diffuse single tumor cell infiltration (HD-type). We determined by DNA microarrays the gene expression profiles of three NL-type and three HD-type long-term GBM cultures. Subsequently, individual genes with different expression levels between the two groups were identified using Significance Analysis of Microarrays (SAM). Real time RT-PCR, immunofluorescence and immunoblot analyses, were performed for a selected subgroup of regulated gene products to confirm the results obtained by the expression analysis. Here, we report the identification of a set of 34 differentially expressed genes in the two types of GBM cultures. Twenty-three of these genes encode for proteins localized to the plasma membrane and 9 of these for proteins are involved in the process of cell adhesion. This study suggests the participation in the diffuse infiltrative/invasive process of GBM cells within the CNS of a novel set of genes coding for membrane-associated proteins, which should be thus susceptible to an inhibition strategy by specific targeting.Massimiliano Monticone and Antonio Daga contributed equally to this work.

EVA1A inhibits GBM cell proliferation by inducing autophagy and apoptosis

Energy Technology Data Exchange (ETDEWEB)

Shen, Xue; Kan, Shifeng; Liu, Zhen [Department of Cell Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191 (China); Lu, Guang [Department of Cell Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191 (China); Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597 (Singapore); Zhang, Xiaoyan [Department of Cell Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191 (China); Chen, Yingyu [Department of Immunology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191 (China); Peking University Center for Human Disease Genomics, Beijing 100191 (China); Bai, Yun, E-mail: baiyun@bjmu.edu.cn [Department of Cell Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191 (China)

2017-03-01

Eva-1 homolog A (EVA1A) is a novel lysosome and endoplasmic reticulum-associated protein involved in autophagy and apoptosis. In this study, we constructed a recombinant adenovirus 5-EVA1A vector (Ad5-EVA1A) to overexpress EVA1A in glioblastoma (GBM) cell lines and evaluated its anti-tumor activities in vitro and in vivo. We found that overexpression of EVA1A in three GBM cell lines (U251, U87 and SHG44) resulted in a suppression of tumor cell growth via activation of autophagy and induction of cell apoptosis in a dose- and time-dependent manner. EVA1A-mediated autophagy was associated with inactivation of the mTOR/RPS6KB1 signaling pathway. Furthermore in vivo, overexpression of EVA1A successfully inhibited tumor growth in NOD/SCID mice. Our data suggest that EVA1A-induced autophagy and apoptosis play a role in suppressing the development of GBM and their up-regulation may be an effective method for treating this form of cancer. - Highlights: • Overexpression of EVA1A suppresses GBM cell growth. • EVA1A induces autophagy through the mTOR/RPS6KB1 pathway. • EVA1A induces GBM cell apoptosis. • EVA1A inhibits the development of GBM in vivo.

The effect of silver nanoparticles (AgNPs) on proliferation and apoptosis of in ovo cultured glioblastoma multiforme (GBM) cells.

Science.gov (United States)

Urbańska, Kaja; Pająk, Beata; Orzechowski, Arkadiusz; Sokołowska, Justyna; Grodzik, Marta; Sawosz, Ewa; Szmidt, Maciej; Sysa, Paweł

2015-01-01

Recently, it has been shown that silver nanoparticles (AgNPs) provide a unique approach to the treatment of tumors, especially those of neuroepithelial origin. Thus, the aim of this study was to evaluate the impact of AgNPs on proliferation and activation of the intrinsic apoptotic pathway of glioblastoma multiforme (GBM) cells cultured in an in ovo model. Human GBM cells, line U-87, were placed on chicken embryo chorioallantoic membrane. After 8 days, the tumors were divided into three groups: control (non-treated), treated with colloidal AgNPs (40 μg/ml), and placebo (tumors supplemented with vehicle only). At the end of the experiment, all tumors were isolated. Assessment of cell proliferation and cell apoptosis was estimated by histological, immunohistochemical, and Western blot analyses. The results show that AgNPs can influence GBM growth. AgNPs inhibit proliferation of GBM cells and seem to have proapoptotic properties. Although there were statistically significant differences between control and AgNP groups in the AI and the levels of active caspase 9 and active caspase 3, the level of these proteins in GBM cells treated with AgNPs seems to be on the border between the spontaneous apoptosis and the induced. Our results indicate that the antiproliferative properties of silver nanoparticles overwhelm proapoptotic ones. Further research focused on the cytotoxic effect of AgNPs on tumor and normal cells should be conducted.

A Large-Scale RNAi Screen Identifies SGK1 as a Key Survival Kinase for GBM Stem Cells.

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Kulkarni, Shreya; Goel-Bhattacharya, Surbhi; Sengupta, Sejuti; Cochran, Brent H

2018-01-01

Glioblastoma multiforme (GBM) is the most common type of primary malignant brain cancer and has a very poor prognosis. A subpopulation of cells known as GBM stem-like cells (GBM-SC) have the capacity to initiate and sustain tumor growth and possess molecular characteristics similar to the parental tumor. GBM-SCs are known to be enriched in hypoxic niches and may contribute to therapeutic resistance. Therefore, to identify genetic determinants important for the proliferation and survival of GBM stem cells, an unbiased pooled shRNA screen of 10,000 genes was conducted under normoxic as well as hypoxic conditions. A number of essential genes were identified that are required for GBM-SC growth, under either or both oxygen conditions, in two different GBM-SC lines. Interestingly, only about a third of the essential genes were common to both cell lines. The oxygen environment significantly impacts the cellular genetic dependencies as 30% of the genes required under hypoxia were not required under normoxic conditions. In addition to identifying essential genes already implicated in GBM such as CDK4, KIF11 , and RAN , the screen also identified new genes that have not been previously implicated in GBM stem cell biology. The importance of the serum and glucocorticoid-regulated kinase 1 (SGK1) for cellular survival was validated in multiple patient-derived GBM stem cell lines using shRNA, CRISPR, and pharmacologic inhibitors. However, SGK1 depletion and inhibition has little effect on traditional serum grown glioma lines and on differentiated GBM-SCs indicating its specific importance in GBM stem cell survival. Implications: This study identifies genes required for the growth and survival of GBM stem cells under both normoxic and hypoxic conditions and finds SGK1 as a novel potential drug target for GBM. Mol Cancer Res; 16(1); 103-14. ©2017 AACR . ©2017 American Association for Cancer Research.

The Fermi GBM Gamma-Ray Burst Catalog: The First Two Years

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Paciesas, W.S.; Meegan, C.A.; von Kienlin, A.; Bhat, P.N.; Bissaldi, E.; Briggs, M.S.; M. Burgess, J.; Chaplin, V.; Connaughton, V.; Diehl, R.; Fishman, G.J.; Fitzpatrick, G.; Foley, S.; H. Gibby, M.; Giles, M.; Goldstein, A.; Greiner, J.; Gruber, D.; Guiriec, S.; van der Horst, A.J.; Kippen, R.M.; Kouveliotou, C.; Lichti, G.; Lin, L.; McBreen, S.; Preece, R.D.; Rau, A.; Tierney, D.; Wilson-Hodge, C.

2012-01-01

The Fermi Gamma-ray Burst Monitor (GBM) is designed to enhance the scientific return from Fermi in studying gamma-ray bursts (GRBs). In its first two years of operation GBM triggered on 491 GRBs. We summarize the criteria used for triggering and quantify the general characteristics of the triggered

Discovery of potent and selective cytotoxic activity of new quinazoline-ureas against TMZ-resistant glioblastoma multiforme (GBM).

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Elkamhawy, Ahmed; Viswanath, Ambily Nath Indu; Pae, Ae Nim; Kim, Hyeon Young; Heo, Jin-Chul; Park, Woo-Kyu; Lee, Chong-Ock; Yang, Heekyoung; Kim, Kang Ho; Nam, Do-Hyun; Seol, Ho Jun; Cho, Heeyeong; Roh, Eun Joo

2015-10-20

Herein, we report new quinazoline-urea based compounds with potent cytotoxic activities against TMZ-resistant glioblastoma multiforme (GBM) cells. Low micromolar IC₅₀ values were exhibited over a panel of three primary GBM patient-derived cell cultures belonging to proneural (GBM-1), mesenchymal (GBM-2), and classical (GBM-3) subtypes. Eight compounds showed excellent selectivity indices for GBM cells comparing to a normal astrocyte cell line. In JC-1 assay, analogues 11, 12, 20, 22, and 24 exerted promising rates of mPTP opening induction towards proneural GBM subtype. Compounds 11, 20, and 24 bound to the translocator protein 18 kDa (TSPO) in submicromolar range using [(3)H] PK-11195 binding affinity assay. A homology model was built and docked models of 11, 12, 20, 22 and 24 were generated for describing their plausible binding modes in TSPO. In 3D clonogenic assay, compound 20 manifested potent tumoricidal effects on TMZ-resistant GBM cells even at submicromolar concentrations. In addition, CYP450 and hERG assays presented a safe toxicity profile of 20. Taken as a whole, this report presents compound 20 as a potent, selective and safe GBM cytotoxic agent which constitutes a promising direction against TMZ-resistant GBM. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Olea europaea leaf extract improves the treatment response of GBM stem cells by modulating miRNA expression.

Science.gov (United States)

Tezcan, Gulcin; Tunca, Berrin; Bekar, Ahmet; Budak, Ferah; Sahin, Saliha; Cecener, Gulsah; Egeli, Unal; Taskapılıoglu, Mevlut Ozgur; Kocaeli, Hasan; Tolunay, Sahsine; Malyer, Hulusi; Demir, Cevdet; Tumen, Gulendam

2014-01-01

The stem-like cells of Glioblastoma multiforme (GBM) tumors (GSCs) are one of the important determinants of recurrence and drug resistance. The aims of the current study were to evaluate the anticancer effect of Olea europaea leaf extract (OLE) on GBM cell lines, the association between OLE and TMZ responses, and the effect of OLE and the OLE-TMZ combination in GSCs and to clarify the molecular mechanism of this effect on the expression of miRNAs related to cell death. The anti-proliferative activity of OLE and the effect of the OLE-TMZ combination were tested in the T98G, U-138MG and U-87MG GBM cell lines using WST-1 assay. The mechanism of cell death was analyzed with Annexin V/FITC and TUNEL assays. The effects of OLE on the expression levels of miR-181b, miR-153, miR-145 and miR-137 and potential mRNA targets were analyzed in GSCs using RT-qPCR. OLE exhibited anti-proliferative effects via apoptosis and necrosis in the GBM cell lines. In addition, OLE significantly induced the expression of miR-153, miR-145, and miR-137 and decreased the expression of the target genes of these miRNAs in GSCs (p GBM cells with different TMZ responses, and this effect is synergistically increased when the cells are treated with a combination of OLE and TMZ. This is the first study to indicate that OLE may interfere with the pluripotency of GSCs by modulating miRNA expression. Further studies are required, but we suggest that OLE may have a potential for advanced therapeutic cancer drug studies in GBM.

Identification of a novel set of genes reflecting different in vivo invasive patterns of human GBM cells

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Monticone Massimiliano

2012-08-01

Full Text Available Abstract Background Most patients affected by Glioblastoma multiforme (GBM, grade IV glioma experience a recurrence of the disease because of the spreading of tumor cells beyond surgical boundaries. Unveiling mechanisms causing this process is a logic goal to impair the killing capacity of GBM cells by molecular targeting. We noticed that our long-term GBM cultures, established from different patients, may display two categories/types of growth behavior in an orthotopic xenograft model: expansion of the tumor mass and formation of tumor branches/nodules (nodular like, NL-type or highly diffuse single tumor cell infiltration (HD-type. Methods We determined by DNA microarrays the gene expression profiles of three NL-type and three HD-type long-term GBM cultures. Subsequently, individual genes with different expression levels between the two groups were identified using Significance Analysis of Microarrays (SAM. Real time RT-PCR, immunofluorescence and immunoblot analyses, were performed for a selected subgroup of regulated gene products to confirm the results obtained by the expression analysis. Results Here, we report the identification of a set of 34 differentially expressed genes in the two types of GBM cultures. Twenty-three of these genes encode for proteins localized to the plasma membrane and 9 of these for proteins are involved in the process of cell adhesion. Conclusions This study suggests the participation in the diffuse infiltrative/invasive process of GBM cells within the CNS of a novel set of genes coding for membrane-associated proteins, which should be thus susceptible to an inhibition strategy by specific targeting. Massimiliano Monticone and Antonio Daga contributed equally to this work

Investigating tumor perfusion by hyperpolarized (13) C MRI with comparison to conventional gadolinium contrast-enhanced MRI and pathology in orthotopic human GBM xenografts

DEFF Research Database (Denmark)

Park, Ilwoo; von Morze, Cornelius; Lupo, Janine M

2016-01-01

glioblastoma (GBM) model for the characterization of tumor perfusion and compared with standard Gd-based dynamic susceptibility contrast (DSC) MRI data and immunohistochemical analysis from resected brains. Distinct HMCP perfusion characteristics were observed within the GBM tumors compared with contralateral...... for tumor that exhibited high levels of hyperpolarized HMCP signal. The results from this study have demonstrated that hyperpolarized HMCP data can be used as an indicator of tumor perfusion in an orthotopic xenograft model for GBM. Magn Reson Med, 2016. © 2016 Wiley Periodicals, Inc....

Using GRB 080723B to cross-calibrate Fermi/GBM and INTEGRAL

International Nuclear Information System (INIS)

Kienlin, A. von; Briggs, M. S.; Connoughton, V.; Preece, R. D.; McBreen, S.; Sazonov, Sergey; Tsygankov, Sergey; Wilson-Hodge, C. A.

2009-01-01

On July 23, 2008 GRB 080723B, a bright GRB lasting about 105 s was detected by the INTEGRAL burst alert system. This burst was also detected by the Fermi Gamma-ray burst monitor. At this time no Fermi/GBM GCN notices were distributed to the public because Fermi was still in commissioning phase. The simultaneous detection of a bright GRB by both satellites gives us the opportunity to cross-calibrate the GBM with the already well-calibrated instruments on-board INTEGRAL, the Spectrometer SPI and the Imager IBIS. Time-resolved spectroscopy of this long and structured GRB is of special importance because Fermi was slewing during the GRB was still ongoing. In this paper we present a first and still preliminary analysis of the GBM spectra and compare them to those obtained by SPI for the same selection of time intervals. A more accurate cross-calibration will be forthcoming when the improved in-flight calibration of GBM is available and the corresponding data and responses can be reprocessed.

Rituximab for the treatment of refractory simultaneous anti-glomerular basement membrane (anti-GBM) and membranous nephropathy.

Science.gov (United States)

Bandak, Ghassan; Jones, Bruce A; Li, Jian; Yee, Jerry; Umanath, Kausik

2014-02-01

Antibody-mediated anti-glomerular basement membrane (anti-GBM) disease occurs rarely in the presence of another B-cell disorder, membranous nephropathy. The coexistence of these two autoimmune disorders would be anticipated to require differing, specific therapies targeted to each disease process. We describe a case of concomitant membranous nephropathy and anti-GBM disease in which conventional therapy, including steroids, plasmapheresis and cyclophosphamide, failed to attenuate the anti-GBM disease, yet responded to an alternative treatment of rituximab. This B-cell directed, monoclonal, chimeric antibody treatment substantially reduced anti-GBM antibody titers and led to discontinuation of plasmapheresis, while maintaining the remission of membranous nephropathy and anti-GBM disease.

GBM-associated mutations and altered protein expression are more common in young patients.

Science.gov (United States)

Ferguson, Sherise D; Xiu, Joanne; Weathers, Shiao-Pei; Zhou, Shouhao; Kesari, Santosh; Weiss, Stephanie E; Verhaak, Roeland G; Hohl, Raymond J; Barger, Geoffrey R; Reddy, Sandeep K; Heimberger, Amy B

2016-10-25

Geriatric glioblastoma (GBM) patients have a poorer prognosis than younger patients, but IDH1/2 mutations (more common in younger patients) confer a favorable prognosis. We compared key GBM molecular alterations between an elderly (age ≥ 70) and younger (18 GBM cohort compared to the older cohort (P GBM cohort, younger patients had significantly more mutations in PDGFRA, PTPN11, SMARCA4, BRAF and TP53. GBMs from 178 elderly patients and 197 young patients were analyzed using DNA sequencing, immunohistochemistry, in situ hybridization, and MGMT-methylation assay to ascertain mutational and amplification/expressional status. Significant molecular differences occurred in GBMs from elderly and young patients. Except for the older cohort's more frequent PTEN mutation and MGMT methylation, younger patients had a higher frequency of potential therapeutic targets.

Microprocessor-based accelerating power level detector

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Nagpal, M.; Zarecki, W.; Albrecht, J.C.

1994-01-01

An accelerating power level detector was built using state-of-the-art microprocessor technology at Powertech Labs Inc. The detector will monitor the real power flowing in two 300 kV transmission lines out of Kemano Hydroelectric Generating Station and will detect any sudden loss of load due to a fault on either line under certain pre-selected power flow conditions. This paper discusses the criteria of operation for the detector and its implementation details, including digital processing, hardware, and software.

Gene expression profiling of anti-GBM glomerulonephritis model: the role of NF-kappaB in immune complex kidney disease.

Science.gov (United States)

Kim, Ju Han; Ha, Il Soo; Hwang, Chang-Il; Lee, Young-Ju; Kim, Jihoon; Yang, Seung-Hee; Kim, Yon Su; Cao, Yun Anna; Choi, Sangdun; Park, Woong-Yang

2004-11-01

Immune complexes may cause an irreversible onset of chronic renal disease. Most patients with chronic renal disease undergo a final common pathway, marked by glomerulosclerosis and interstitial fibrosis. We attempted to draw a molecular map of anti-glomerular basement membrane (GBM) glomerulonephritis in mice using oligonucleotide microarray technology. Kidneys were harvested at days 1, 3, 7, 11, and 16 after inducing glomerulonephritis by using anti-GBM antibody. In parallel with examining the biochemical and histologic changes, gene expression profiles were acquired against five pooled control kidneys. Gene expression levels were cross-validated by either reverse transcription-polymerase chain reaction (RT-PCR), real-time PCR, or immunohistochemistry. Pathologic changes in anti-GBM glomerulonephritis were confirmed in both BALB/c and C57BL/6 strains. Among the 13,680 spotted 65mer oligonucleotides, 1112 genes showing significant temporal patterns by permutation analysis of variance (ANOVA) with multiple testing correction [false discovery ratio (FDR) mouse anti-GBM glomerulonephritis model, providing a comprehensive overview on the mechanism governing the initiation and the progression of inflammatory renal disease.

Recruitment of bone marrow derived cells during anti-angiogenic therapy in GBM : Bone marrow derived cell in GBM

NARCIS (Netherlands)

Boer, Jennifer C.; Walenkamp, Annemiek M. E.; den Dunnen, Wilfred F. A.

2014-01-01

Glioblastoma (GBM) is a highly vascular tumor characterized by rapid and invasive tumor growth, followed by oxygen depletion, hypoxia and neovascularization, which generate a network of disorganized, tortuous and permeable vessels. Recruitment of bone marrow derived cells (BMDC) is crucial for

Performance of two strategies for urgent ANCA and anti-GBM analysis in vasculitis.

Science.gov (United States)

de Joode, Anoek A E; Roozendaal, Caroline; van der Leij, Marcel J; Bungener, Laura B; Sanders, Jan Stephan F; Stegeman, Coen A

2014-02-01

In anti-neutrophil cytoplasmic antibodies (ANCA) associated small vessel vasculitis (AAV), rapid testing for ANCA and anti-glomerular basement membrane (GBM) antibodies may be beneficial for therapeutic purpose. We analysed the diagnostic performance of two rapid ANCA and anti-GBM test methods in 260 patients with suspected AAV. Between January 2004 and November 2010, we analysed 260 samples by qualitative Dotblot (Biomedical Diagnostics); retrospective analysis followed with directly coated highly sensitive automated Phadia ELiA and ELiA anti-GBM. Results were related to the final clinical diagnosis and compared with routine capture ELISA. Seventy-four patients had a final diagnosis of AAV (n=62) or anti-GBM disease (n=12). Both Dotblot and ELiA detected all 12 cases of anti-GBM disease; 2 false positive results were found. Dotblot detected ANCA in 56 of 62 AAV patients (sensitivity 90%, NPV 97%), and showed 5 false positives (specificity 97%, PPV 90%). The Phadia ELiA anti-PR3(s) or anti-MPO(s) was positive in 57 of 62 AAV patients (sensitivity 92%, NPV 97%), and had 5 false positives (specificity 97%, PPV 88%). Routine capture ELISA was equally accurate (sensitivity 94%, specificity 97%, PPV 88%, NPV 98%). The Dotblot and Phadia ELiA on anti-GBM, anti-PR3(s) and anti-MPO(s) performed excellently; results were almost identical to routine ELISA. When suspicion of AAV or anti-GBM disease is high and diagnosis is urgently needed, both tests are very powerful for rapid serological diagnosis. Further studies have to confirm the test performances in samples routinely presented for ANCA testing and in follow-up of positive patients. Copyright © 2013 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

The Interplanetary Network Supplement to the Fermi GBM Catalog - An AO-2 and AO-3 Guest Investigator Project

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Hurley, K.; Briggs, M.; Connaughton, V.; Meegan, C.; von Kienlin, A.; Rau, A.; Zhang, X.; Golenetskii, S.; Aptekar, R.; Mazets, E.;

DW-MRI as a Predictive Biomarker of Radiosensitization of GBM through Targeted Inhibition of Checkpoint Kinases.

Science.gov (United States)

Williams, Terence M; Galbán, Stefanie; Li, Fei; Heist, Kevin A; Galbán, Craig J; Lawrence, Theodore S; Holland, Eric C; Thomae, Tami L; Chenevert, Thomas L; Rehemtulla, Alnawaz; Ross, Brian D

2013-04-01

The inherent treatment resistance of glioblastoma (GBM) can involve multiple mechanisms including checkpoint kinase (Chk1/2)-mediated increased DNA repair capability, which can attenuate the effects of genotoxic chemotherapies and radiation. The goal of this study was to evaluate diffusion-weighted magnetic resonance imaging (DW-MRI) as a biomarker for Chk1/2 inhibitors in combination with radiation for enhancement of treatment efficacy in GBM. We evaluated a specific small molecule inhibitor of Chk1/2, AZD7762, in combination with radiation using in vitro human cell lines and in vivo using a genetically engineered GBM mouse model. DW-MRI and T1-contrast MRI were used to follow treatment effects on intracranial tumor cellularity and growth rates, respectively. AZD7762 inhibited clonal proliferation in a panel of GBM cell lines and increased radiosensitivity in p53-mutated GBM cell lines to a greater extent compared to p53 wild-type cells. In vivo efficacy of AZD7762 demonstrated a dose-dependent inhibitory effect on GBM tumor growth rate and a reduction in tumor cellularity based on DW-MRI scans along with enhancement of radiation efficacy. DW-MRI was found to be a useful imaging biomarker for the detection of radiosensitization through inhibition of checkpoint kinases. Chk1/2 inhibition resulted in antiproliferative activity, prevention of DNA damage-induced repair, and radiosensitization in preclinical GBM tumor models, both in vitro and in vivo. The effects were found to be maximal in p53-mutated GBM cells. These results provide the rationale for integration of DW-MRI in clinical translation of Chk1/2 inhibition with radiation for the treatment of GBM.

Glioblastoma (GBM) effects on quantitative MRI of contralateral normal appearing white matter.

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Mehrabian, Hatef; Lam, Wilfred W; Myrehaug, Sten; Sahgal, Arjun; Stanisz, Greg J

2018-03-28

The objective was to investigate (with quantitative MRI) whether the normal appearing white matter (NAWM) of glioblastoma (GBM) patients on the contralateral side (cNAWM) was different from NAWM of healthy controls. Thirteen patients with newly diagnosed GBM and nine healthy age-matched controls were MRI-scanned with quantitative magnetization transfer (qMT), chemical exchange saturation transfer (CEST), and transverse relaxation time (T 2 )-mapping. MRI scans were performed after surgery and before chemo-radiation treatment. Comprehensive qMT, CEST, T 2 data were acquired. A two-pool MT model was fit to qMT data in transient state, to calculate MT model parameters [Formula: see text]. CEST signal was isolated by removing the contributions from the MT and direct water saturation, and CEST signal was calculated for Amide (CEST Amide ), Amine (CEST Amine ) and nuclear overhauser effect, NOE (CEST NOE ). There was no difference between GBM patients and normal controls in the qMT properties of the macromolecular pool [Formula: see text]. However, their free water pool spectrum was different (1/R a T 2a , patient  = 28.1 ± 3.9, 1/R a T 2a , control  = 25.0 ± 1.1, p = 0.03). This difference could be attributed to the difference in their T 2 time ([Formula: see text] = 83 ± 4, [Formula: see text] = 88 ± 1, p = 0.004). CEST signals were statistically significantly different with the CEST Amide having the largest difference between the two cohorts (CEST Amide,patient  = 2.8 ± 0.4, CEST Amide,control  = 3.4 ± 0.5, p = 0.009). CEST in cNAWM of GBM patients was lower than healthy controls which could be caused by modified brain metabolism due to tumor cell infiltration. There was no difference in MT properties of the patients and controls, however, the differences in free water pool properties were mainly due to reduced T 2 in cNAWM of the patients (resulting from structural changes and increased cellularity).

Anti-glomerular basement membrane (anti-GBM) disease accompanied by vasculitis that was not positive for antineutrophil cytoplasmic antibodies to myeloperoxidase and proteinase 3: a report of two cases and the incidence of anti-GBM disease at one institution.

Science.gov (United States)

Nakabayashi, Kimimasa; Fujioka, Yasunori; Arimura, Yoshihiro; Fukuoka, Toshihito; Marumo, Tomohumi; Umino, Michiru; Kamiya, Yasushi; Okai, Takahiro; Tsurumaki, Shigeru; Nagasawa, Toshihiko; Yamada, Akira

2011-08-01

Anti-glomerular basement membrane (anti-GBM) disease is thought to be distinct from vasculitis. In contrast, there have been several papers suggesting the presence of angiitis in cases that were positive for anti-GBM antibody (Ab), as well as for either myeloperoxidase (MPO)- or proteinase 3 (PR3)-anti-neutrophil cytoplasmic antibody (ANCA) (Group I). We experienced four patients who had anti-GBM Abs, but not MPO- and PR3-ANCA (Group II), and two of these patients were found to have vasculitis. Therefore, we performed an in-depth study on these two patients. The patients with anti-GBM disease were isolated from 578 cases whose renal tissues were examined, and they were categorized into two groups. We have already published the data about Group I. We then proceeded to study two vasculitic patients in Group II clinically, pathologically, and serologically. The anti-GBM Ab and ANCA levels were detected by enzyme-linked immunosorbent assays. Renal specimens were studied by routine staining as well as immunohistochemical investigations of CD31 and type IV collagen. The total number of patients with anti-GBM disease was 7 (7/578 = 1.2%), with 3 patients belonging to Group I and 4 patients belonging to Group II. Two patients in Group II were diagnosed to have vasculitis, but the remaining 2 patients did not. One vasculitic patient was complicated by pulmonary hemorrhage, while the other vasculitic patient displayed peripheral neuropathy as well as a small cavity lesion in the lung. The latter patient was found to be positive for perinuclear (p)-ANCA, but not for any other ANCA subsets. The renal pathology in the two vasculitic patients showed crescentic glomerulonephritis (CSGN) and immunoglobulin (Ig) G linear deposits along the glomerular capillary loops. The former patient showed fibrinoid angiitis in an afferent arteriole as well as peritubular capillaritis. The latter patient demonstrated peritubular capillaritis. These peritubular capillaritides were diagnosed by

Photospheric Emission in the Joint GBM and Konus Prompt Spectra of GRB 120323A

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Guiriec, S.; Kouveliotou, C. [Department of Physics, The George Washington University, 725 21st Street NW, Washington, DC 20052 (United States); Gehrels, N.; McEnery, J. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Hartmann, D. H., E-mail: sylvain.guiriec@nasa.gov [Department of Physics and Astronomy, Clemson University, Kinard Lab of Physics (United States)

2017-09-10

GRB 120323A is a very intense short gamma -ray burst (GRB) detected simultaneously during its prompt γ -ray emission phase with the Gamma-ray Burst Monitor (GBM) on board the Fermi Gamma-ray Space Telescope and the Konus experiment on board the Wind satellite. GBM and Konus operate in the keV–MeV regime; however, the GBM range is broader toward both the low and the high parts of the γ -ray spectrum. Analyses of such bright events provide a unique opportunity to check the consistency of the data analysis as well as cross-calibrate the two instruments. We performed time-integrated and coarse time-resolved spectral analysis of GRB 120323A prompt emission. We conclude that the analyses of GBM and Konus data are only consistent when using a double-hump spectral shape for both data sets; in contrast, the single hump of the empirical Band function, traditionally used to fit GRB prompt emission spectra, leads to significant discrepancies between GBM and Konus analysis results. Our two-hump model is a combination of a thermal-like and a non-thermal component. We interpret the first component as a natural manifestation of the jet photospheric emission.

A PTEN-COL17A1 fusion gene and its novel regulatory role in Collagen XVII expression and GBM malignance.

Science.gov (United States)

Yan, Xiaoyan; Zhang, Chuanbao; Liang, Tingyu; Yang, Fan; Wang, Haoyuan; Wu, Fan; Wang, Wen; Wang, Zheng; Cheng, Wen; Xu, Jiangnan; Jiang, Tao; Chen, Jing; Ding, Yaozhong

2017-10-17

Collagen XVII expression has recently been demonstrated to be correlated with the tumor malignance. While Collagen XVII is known to be widely distributed in neurons of the human brain, its precise role in pathogenesis of glioblastoma multiforme (GBM) is unknown. In this study, we identified and characterized a new PTEN-COL17A1 fusion gene in GMB using transcriptome sequencing. Although fusion gene did not result in measurable fusion protein production, its presence is accompanied with high levels of COL17A1 expression, revealed a novel regulatory mechanism of Collagen XVII expression by PTEN-COL17A1 gene fusion. Knocked down Collagen XVII expression in glioma cell lines resulted in decreased tumor invasiveness, along with significant reduction of MMP9 expression, while increased Collagen XVII expression promotes invasive activities of glioma cells and associated with GBM recurrences. Together, our results uncovered a new PTEN-COL17A1 fusion gene and its novel regulatory role in Collagen XVII expression and GBM malignance, and demonstrated that COL17A1 could serve as a useful prognostic biomarker and therapeutic targets for GBM.

The Fermi Gamma-ray Burst Monitor (GBM) Terrestrial Gamma-ray Flash (TGF) Catalog

Science.gov (United States)

Briggs, M. S.; Roberts, O.; Fitzpatrick, G.; Stanbro, M.; Cramer, E.; Mailyan, B. G.; McBreen, S.; Connaughton, V.; Grove, J. E.; Chekhtman, A.; Holzworth, R.

2017-12-01

The revised Second Fermi GBM TGF catalog includes data on 4144 TGFs detected by the Fermi Gamma-ray Burst Monitor through 2016 July 31. The catalog includes 686 bright TGFs there were detected in orbit and 4135 TGFs that were discovered by ground analysis of GBM data (the two samples overlap). Thirty of the events may have been detected as electrons and positrons rather than gamma-rays: Terrestrial Electron Beams (TEBs). We also provide results from correlating the GBM TGFs with VLF radio detections of the World Wide Lightning Location Network (WWLLN). TGFs with WWLLN associations have their localization uncertainties improved from 800 to 10 km, making it possible to identify specific thunderstorms responsible for the TGFs and opening up new types of scientific investigations. There are 1544 TGFs with WWLLN associations; maps are provided for these and the other TGFs of the catalog. The data tables of the catalog are available for use by the scientific community at the Fermi Science Support Center, at https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/tgf/.

ON THE FERMI -GBM EVENT 0.4 s AFTER GW150914

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Greiner, J.; Yu, H.-F. [Max Planck Institute for Extraterrestrial Physics, Giessenbachstrasse, D-85748 Garching (Germany); Burgess, J. M. [Oskar Klein Centre for Cosmoparticle Physics, SE-106 91 Stockholm (Sweden); Savchenko, V., E-mail: jcg@mpe.mpg.de, E-mail: sptfung@mpe.mpg.de, E-mail: jamesb@kth.se, E-mail: savchenk@apc.in2p3.fr [Francois Arago Centre, APC, Université Paris Diderot, CNRS/IN2P3, CEA/Irfu, Observatoire Paris, Sorbonne Paris Cité, 10 rue Alice Domon et Léonie Duquet, F-75205 Paris Cedex 13 (France)

2016-08-20

In view of the recent report by Connaughton et al., we analyze continuous time-tagged event (TTE) data of Fermi -gamma-ray burst monitor (GBM) around the time of the gravitational-wave event GW 150914. We find that after proper accounting for low-count statistics, the GBM transient event at 0.4 s after GW 150914 is likely not due to an astrophysical source, but consistent with a background fluctuation, removing the tension between the INTEGRAL /ACS non-detection and GBM. Additionally, reanalysis of other short GRBs shows that without proper statistical modeling the fluence of faint events is over-predicted, as verified for some joint GBM–ACS detections of short GRBs. We detail the statistical procedure to correct these biases. As a result, faint short GRBs, verified by ACS detections, with significances in the broadband light curve even smaller than that of the GBM–GW150914 event are recovered as proper non-zero source, while the GBM–GW150914 event is consistent with zero fluence.

Farewell to GBM-O: Genomic and transcriptomic profiling of glioblastoma with oligodendroglioma component reveals distinct molecular subgroups.

Science.gov (United States)

Hinrichs, Benjamin H; Newman, Scott; Appin, Christina L; Dunn, William; Cooper, Lee; Pauly, Rini; Kowalski, Jeanne; Rossi, Michael R; Brat, Daniel J

2016-01-13

Glioblastoma with oligodendroglioma component (GBM-O) was recognized as a histologic pattern of glioblastoma (GBM) by the World Health Organization (WHO) in 2007 and is distinguished by the presence of oligodendroglioma-like differentiation. To better understand the genetic underpinnings of this morphologic entity, we performed a genome-wide, integrated copy number, mutational and transcriptomic analysis of eight (seven primary, primary secondary) cases. Three GBM-O samples had IDH1 (p.R132H) mutations; two of these also demonstrated 1p/19q co-deletion and had a proneural transcriptional profile, a molecular signature characteristic of oligodendroglioma. The additional IDH1 mutant tumor lacked 1p/19q co-deletion, harbored a TP53 mutation, and overall, demonstrated features most consistent with IDH mutant (secondary) GBM. Finally, five tumors were IDH wild-type (IDHwt) and had chromosome seven gains, chromosome 10 losses, and homozygous 9p deletions (CDKN2A), alterations typical of IDHwt (primary) GBM. IDHwt GBM-Os also demonstrated EGFR and PDGFRA amplifications, which correlated with classical and proneural expression subtypes, respectively. Our findings demonstrate that GBM-O is composed of three discrete molecular subgroups with characteristic mutations, copy number alterations and gene expression patterns. Despite displaying areas that morphologically resemble oligodendroglioma, the current results indicate that morphologically defined GBM-O does not correspond to a particular genetic signature, but rather represents a collection of genetically dissimilar entities. Ancillary testing, especially for IDH and 1p/19q, should be used for determining these molecular subtypes.

Magnetic Field Requirements for a Detector at the Linear Collider Using a TPC as Main Tracking Device

CERN Document Server

Klempt, W

2010-01-01

This note describes the requirements to the magnetic field which occur in an ILD like detector at ILC or CLIC. In particular we describe requirements introduced by choosing a TPC as main tracking detector.

Hedgehog signaling pathway is active in GBM with GLI1 mRNA expression showing a single continuous distribution rather than discrete high/low clusters.

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Chandra, Vikas; Das, Tapojyoti; Gulati, Puneet; Biswas, Nidhan K; Rote, Sarang; Chatterjee, Uttara; Ghosh, Samarendra N; Deb, Sumit; Saha, Suniti K; Chowdhury, Anup K; Ghosh, Subhashish; Rudin, Charles M; Mukherjee, Ankur; Basu, Analabha; Dhara, Surajit

2015-01-01

Hedgehog (Hh) signaling pathway is a valid therapeutic target in a wide range of malignancies. We focus here on glioblastoma multiforme (GBM), a lethal malignancy of the central nervous system (CNS). By analyzing RNA-sequencing based transcriptomics data on 149 clinical cases of TCGA-GBM database we show here a strong correlation (r = 0.7) between GLI1 and PTCH1 mRNA expression--as a hallmark of the canonical Hh-pathway activity in this malignancy. GLI1 mRNA expression varied in 3 orders of magnitude among the GBM patients of the same cohort showing a single continuous distribution-unlike the discrete high/low-GLI1 mRNA expressing clusters of medulloblastoma (MB). When compared with MB as a reference, the median GLI1 mRNA expression in GBM appeared 14.8 fold lower than that of the "high-Hh" cluster of MB but 5.6 fold higher than that of the "low-Hh" cluster of MB. Next, we demonstrated statistically significant up- and down-regulation of GLI1 mRNA expressions in GBM patient-derived low-passage neurospheres in vitro by sonic hedgehog ligand-enriched conditioned media (shh-CM) and by Hh-inhibitor drug vismodegib respectively. We also showed clinically achievable dose (50 μM) of vismodegib alone to be sufficient to induce apoptosis and cell cycle arrest in these low-passage GBM neurospheres in vitro. Vismodegib showed an effect on the neurospheres, both by down-regulating GLI1 mRNA expression and by inducing apoptosis/cell cycle arrest, irrespective of their relative endogenous levels of GLI1 mRNA expression. We conclude from our study that this single continuous distribution pattern of GLI1 mRNA expression technically puts almost all GBM patients in a single group rather than discrete high- or low-clusters in terms of Hh-pathway activity. That is suggestive of therapies with Hh-pathway inhibitor drugs in this malignancy without a need for further stratification of patients on the basis of relative levels of Hh-pathway activity among them.

Tumour cell dormancy as a contributor to the reduced survival of GBM patients who received standard therapy.

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Tong, Luqing; Yi, Li; Liu, Peidong; Abeysekera, Iruni Roshanie; Hai, Long; Li, Tao; Tao, Zhennan; Ma, Haiwen; Xie, Yang; Huang, Yubao; Yu, Shengping; Li, Jiabo; Yuan, Feng; Yang, Xuejun

2018-07-01

Glioblastoma multiforme (GBM) is a fatal cancer with varying life expectancy, even for patients undergoing the same standard therapy. Identification of differentially expressed genes in GBM patients with different survival rates may benefit the development of effective therapeutic strategies. In the present study, key pathways and genes correlated with survival in GBM patients were screened with bioinformatic analysis. Included in the study were 136 eligible patients who had undertaken surgical resection of GBM followed by temozolomide (TMZ) chemoradiation and long-term therapy with TMZ. A total of 383 differentially expressed genes (DEGs) related to GBM survival were identified. Gene Ontology and pathway enrichment analysis as well as hub gene screening and module analysis were performed. As expected, angiogenesis and migration of GBM cells were closely correlated with a poor prognosis. Importantly, the results also indicated that cell dormancy was an essential contributor to the reduced survival of GBM patients. Given the lack of specific targeted genes and pathways known to be involved in tumour cell dormancy, we proposed enriched candidate genes related to the negative regulation of cell proliferation, signalling pathways regulating pluripotency of stem cells and neuroactive ligand-receptor interaction, and 3 hub genes (FTH1, GRM1 and DDIT3). Maintaining persistent cell dormancy or preventing tumour cells from entering dormancy during chemoradiation should be a promising therapeutic strategy.

Galectin-9 ameliorates anti-GBM glomerulonephritis by inhibiting Th1 and Th17 immune responses in mice.

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Zhang, Qian; Luan, Hong; Wang, Le; He, Fan; Zhou, Huan; Xu, Xiaoli; Li, Xingai; Xu, Qing; Niki, Toshiro; Hirashima, Mitsuomi; Xu, Gang; Lv, Yongman; Yuan, Jin

2014-04-15

Antiglomerular basement membrane glomerulonephritis (anti-GBM GN) is a Th1- and Th17-predominant autoimmune disease. Galectin-9 (Gal-9), identified as the ligand of Tim-3, functions in diverse biological processes and leads to the apoptosis of CD4(+)Tim-3(+) T cells. It is still unclear how Gal-9 regulates the functions of Th1 and Th17 cells and prevents renal injury in anti-GBM GN. In this study, Gal-9 was administered to anti-GBM GN mice for 7 days. We found that Gal-9 retarded the increase of Scr, ameliorated renal tubular injury, and reduced the formation of crescents. The infiltration of Th1 and Th17 cells into the spleen and kidneys significantly decreased in Gal-9-treated nephritic mice. The reduced infiltration of Th1 and Th17 cells might be associated with the downregulation of CCL-20, CXCL-9, and CXCL-10 mRNAs in the kidney. In parallel, the blood levels of IFN-γ and IL-17A declined in Gal-9-treated nephritic mice at days 21 and 28. In addition, an enhanced Th2 cell-mediated immune response was observed in the kidneys of nephritic mice after a 7-day injection of Gal-9. In conclusion, the protective role of Gal-9 in anti-GBM GN is associated with the inhibition of Th1 and Th17 cell-mediated immune responses and enhanced Th2 immunity in the kidney.

Benzyl isothiocyanate alters the gene expression with cell cycle regulation and cell death in human brain glioblastoma GBM 8401 cells.

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Tang, Nou-Ying; Chueh, Fu-Shin; Yu, Chien-Chih; Liao, Ching-Lung; Lin, Jen-Jyh; Hsia, Te-Chun; Wu, King-Chuen; Liu, Hsin-Chung; Lu, Kung-Wen; Chung, Jing-Gung

2016-04-01

Glioblastoma multiforme (GBM) is a highly malignant devastating brain tumor in adults. Benzyl isothiocyanate (BITC) is one of the isothiocyanates that have been shown to induce human cancer cell apoptosis and cell cycle arrest. Herein, the effect of BITC on cell viability and apoptotic cell death and the genetic levels of human brain glioblastoma GBM 8401 cells in vitro were investigated. We found that BITC induced cell morphological changes, decreased cell viability and the induction of cell apoptosis in GBM 8401 cells was time-dependent. cDNA microarray was used to examine the effects of BITC on GBM 8401 cells and we found that numerous genes associated with cell death and cell cycle regulation in GBM 8401 cells were altered after BITC treatment. The results show that expression of 317 genes was upregulated, and two genes were associated with DNA damage, the DNA-damage-inducible transcript 3 (DDIT3) was increased 3.66-fold and the growth arrest and DNA-damage-inducible α (GADD45A) was increased 2.34-fold. We also found that expression of 182 genes was downregulated and two genes were associated with receptor for cell responses to stimuli, the EGF containing fibulin-like extracellular matrix protein 1 (EFEMP1) was inhibited 2.01-fold and the TNF receptor-associated protein 1 (TRAP1) was inhibited 2.08-fold. BITC inhibited seven mitochondria ribosomal genes, the mitochondrial ribosomal protein; tumor protein D52 (MRPS28) was inhibited 2.06-fold, the mitochondria ribosomal protein S2 (MRPS2) decreased 2.07-fold, the mitochondria ribosomal protein L23 (MRPL23) decreased 2.08-fold, the mitochondria ribosomal protein S2 (MRPS2) decreased 2.07-fold, the mitochondria ribosomal protein S12 (MRPS12) decreased 2.08-fold, the mitochondria ribosomal protein L12 (MRPL12) decreased 2.25-fold and the mitochondria ribosomal protein S34 (MRPS34) was decreased 2.30-fold in GBM 8401 cells. These changes of gene expression can provide the effects of BITC on the genetic level and are

THE FERMI –GBM THREE-YEAR X-RAY BURST CATALOG

Energy Technology Data Exchange (ETDEWEB)

Jenke, P. A. [CSPAR, SPA University of Alabama in Huntsville, Huntsville, AL 35805 (United States); Linares, M. [Instituto de Astrofísica de Canarias, c/Vía Láctea s/n, E-38205 La Laguna, Tenerife (Spain); Connaughton, V.; Camero-Arranz, A.; Finger, M. H. [Universities Space Research Association, Huntsville, AL 35805 (United States); Beklen, E. [Department of Physics, Suleyman Demirel University, 32260, Isparta (Turkey); Wilson-Hodge, C. A. [Marshall Space Flight Center, Huntsville, AL 35812 (United States)

2016-08-01

The Fermi Gamma-ray Burst Monitor (GBM) is an all-sky gamma-ray monitor well known in the gamma-ray burst (GRB) community. Although GBM excels in detecting the hard, bright extragalactic GRBs, its sensitivity above 8 keV and its all-sky view make it an excellent instrument for the detection of rare, short-lived Galactic transients. In 2010 March, we initiated a systematic search for transients using GBM data. We conclude this phase of the search by presenting a three-year catalog of 1084 X-ray bursts. Using spectral analysis, location, and spatial distributions we classified the 1084 events into 752 thermonuclear X-ray bursts, 267 transient events from accretion flares and X-ray pulses, and 65 untriggered gamma-ray bursts. All thermonuclear bursts have peak blackbody temperatures broadly consistent with photospheric radius expansion (PRE) bursts. We find an average rate of 1.4 PRE bursts per day, integrated over all Galactic bursters within about 10 kpc. These include 33 and 10 bursts from the ultra-compact X-ray binaries 4U 0614+09 and 2S 0918-549, respectively. We discuss these recurrence times and estimate the total mass ejected by PRE bursts in our Galaxy.

Accumulation of worn-out GBM material substantially contributes to mesangial matrix expansion in diabetic nephropathy

NARCIS (Netherlands)

Kriz, Wilhelm; Loewen, Jana; Federico, Giuseppina; van den Born, Jacob; Groene, Elisabeth; Groene, Hermann Josef

2017-01-01

Thickening of the glomerular basement membrane (GBM) and expansion of the mesangial matrix are hallmarks of diabetic nephropathy (DN), generally considered to emerge from different sites of overproduction: GBM components from podocytes and mesangial matrix from mesangial cells. Reevaluation of 918

Analysis of single nucleotide variants of HFE gene and association to survival in The Cancer Genome Atlas GBM data.

Science.gov (United States)

Lee, Sang Y; Zhu, Junjia; Salzberg, Anna C; Zhang, Bo; Liu, Dajiang J; Muscat, Joshua E; Langan, Sara T; Connor, James R

2017-01-01

Human hemochromatosis protein (HFE) is involved in iron metabolism. Two major HFE polymorphisms, H63D and C282Y, have been associated with an increased risk of cancers. Previously, we reported decreased gender effects in overall survival based on H63D or C282Y HFE polymorphisms patients with glioblastoma multiforme (GBM). However, the effect of other single nucleotide variation (SNV) in the HFE gene on the cancer development and progression has not been systematically studied. To expand our finding in a larger sample, and to identify other HFE SNV, we analyzed the frequency of somatic SNV in HFE gene and its relationship to survival in GBM patients using The Cancer Genome Atlas (TCGA) GBM (Caucasian only) database. We found 9 SNVs with increased frequency in blood normal of TCGA GBM patients compared to the 1000Genome. Among 9 SNVs, 7 SNVs were located in the intron and 2 SNVs (i.e., H63D, C282Y) in the exon of HFE gene. The statistical analysis demonstrated that blood normal samples of TCGA GBM have more H63D (p = 0.0002, 95% Confidence interval (CI): 0.2119-0.3223) or C282Y (p = 0.0129, 95% CI: 0.0474-0.1159) HFE polymorphisms than 1000Genome. The Kaplan-Meier survival curve for the 264 GBM samples revealed no difference between wild type (WT) HFE and H63D, and WT HFE and C282Y GBM patients. In addition, there was no difference in the survival of male/female GBM patients based on HFE genotype. There was no correlation between HFE expression and survival. In conclusion, the current results suggest that somatic HFE polymorphisms do not impact GBM patients' survival in the TCGA data set of GBM.

Analysis of single nucleotide variants of HFE gene and association to survival in The Cancer Genome Atlas GBM data.

Directory of Open Access Journals (Sweden)

Sang Y Lee

Full Text Available Human hemochromatosis protein (HFE is involved in iron metabolism. Two major HFE polymorphisms, H63D and C282Y, have been associated with an increased risk of cancers. Previously, we reported decreased gender effects in overall survival based on H63D or C282Y HFE polymorphisms patients with glioblastoma multiforme (GBM. However, the effect of other single nucleotide variation (SNV in the HFE gene on the cancer development and progression has not been systematically studied. To expand our finding in a larger sample, and to identify other HFE SNV, we analyzed the frequency of somatic SNV in HFE gene and its relationship to survival in GBM patients using The Cancer Genome Atlas (TCGA GBM (Caucasian only database. We found 9 SNVs with increased frequency in blood normal of TCGA GBM patients compared to the 1000Genome. Among 9 SNVs, 7 SNVs were located in the intron and 2 SNVs (i.e., H63D, C282Y in the exon of HFE gene. The statistical analysis demonstrated that blood normal samples of TCGA GBM have more H63D (p = 0.0002, 95% Confidence interval (CI: 0.2119-0.3223 or C282Y (p = 0.0129, 95% CI: 0.0474-0.1159 HFE polymorphisms than 1000Genome. The Kaplan-Meier survival curve for the 264 GBM samples revealed no difference between wild type (WT HFE and H63D, and WT HFE and C282Y GBM patients. In addition, there was no difference in the survival of male/female GBM patients based on HFE genotype. There was no correlation between HFE expression and survival. In conclusion, the current results suggest that somatic HFE polymorphisms do not impact GBM patients' survival in the TCGA data set of GBM.

VizieR Online Data Catalog: Short GRBs with Fermi GBM and Swift BAT (Burns+, 2016)

Science.gov (United States)

Burns, E.; Connaughton, V.; Zhang, B.-B.; Lien, A.; Briggs, M. S.; Goldstein, A.; Pelassa, V.; Troja, E.

2018-01-01

Compact binary system mergers are expected to generate gravitational radiation detectable by ground-based interferometers. A subset of these, the merger of a neutron star with another neutron star or a black hole, are also the most popular model for the production of short gamma-ray bursts (GRBs). The Swift Burst Alert Telescope (BAT) and the Fermi Gamma-ray Burst Monitor (GBM) trigger on short GRBs (SGRBs) at rates that reflect their relative sky exposures, with the BAT detecting 10 per year compared to about 45 for GBM. We examine the SGRB populations detected by Swift BAT and Fermi GBM. (4 data files).

Methods and Results of a Search for Gravitational Waves Associated with Gamma-Ray Bursts Using the GEO 600, LIGO, and Virgo Detectors

Science.gov (United States)

Aasi, J.; Abbott, B. P.; Abbott, R.; Abbott, T.; Abernathy, M. R.; Acernese, F.; Ackley, K.; Adams, C.; Adams, T.; Blackburn, Lindy L.;

Demethoxycurcumin Retards Cell Growth and Induces Apoptosis in Human Brain Malignant Glioma GBM 8401 Cells

Directory of Open Access Journals (Sweden)

Tzuu-Yuan Huang

2012-01-01

Full Text Available Demethoxycurcumin (DMC; a curcumin-related demethoxy compound has been recently shown to display antioxidant and antitumor activities. It has also produced a potent chemopreventive action against cancer. In the present study, the antiproliferation (using the MTT assay, DMC was found to have cytotoxic activities against GBM 8401 cell with IC50 values at 22.71 μM and induced apoptosis effects of DMC have been investigated in human brain malignant glioma GBM 8401 cells. We have studied the mitochondrial membrane potential (MMP, DNA fragmentation, caspase activation, and NF-κB transcriptional factor activity. By these approaches, our results indicated that DMC has produced an inhibition of cell proliferation as well as the activation of apoptosis in GBM 8401 cells. Both effects were observed to increase in proportion with the dosage of DMC treatment, and the apoptosis was induced by DMC in human brain malignant glioma GBM 8401 cells via mitochondria- and caspase-dependent pathways.

The InterPlanetary Network Supplement to the Second Fermi GBM Catalog of Cosmic Gamma-Ray Bursts

Energy Technology Data Exchange (ETDEWEB)

Hurley, K. [University of California, Berkeley, Space Sciences Laboratory, 7 Gauss Way, Berkeley, CA 94720-7450 (United States); Aptekar, R. L.; Golenetskii, S. V.; Frederiks, D. D.; Svinkin, D. S. [Ioffe Institute, Politekhnicheskaya 26, St. Petersburg 194021 (Russian Federation); Pal’shin, V. D. [Vedeneeva 2-31, St. Petersburg (Russian Federation); Briggs, M. S.; Meegan, C. [University of Alabama in Huntsville, NSSTC, 320 Sparkman Drive, Huntsville, AL 35805 (United States); Connaughton, V. [Universities Space Research Association, NSSTC, 320 Sparkman Drive, Huntsville, AL 35805 (United States); Goldsten, J. [Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723 (United States); Boynton, W.; Fellows, C.; Harshman, K. [University of Arizona, Department of Planetary Sciences, Tucson, Arizona 85721 (United States); Mitrofanov, I. G.; Golovin, D. V.; Kozyrev, A. S.; Litvak, M. L.; Sanin, A. B. [Space Research Institute, 84/32, Profsoyuznaya, Moscow 117997 (Russian Federation); Rau, A.; Kienlin, A. von, E-mail: khurley@ssl.berkeley.edu [Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse, Postfach 1312, Garching, D-85748 (Germany); and others

2017-04-01

InterPlanetary Network (IPN) data are presented for the gamma-ray bursts in the second Fermi Gamma-Ray Burst Monitor (GBM) catalog. Of the 462 bursts in that catalog between 2010 July 12 and 2012 July 11, 428, or 93%, were observed by at least 1 other instrument in the 9-spacecraft IPN. Of the 428, the localizations of 165 could be improved by triangulation. For these bursts, triangulation gives one or more annuli whose half-widths vary between about 2.′3° and 16°, depending on the peak flux, fluence, time history, arrival direction, and the distance between the spacecraft. We compare the IPN localizations with the GBM 1 σ , 2 σ , and 3 σ error contours and find good agreement between them. The IPN 3 σ error boxes have areas between about 8 square arcminutes and 380 square degrees, and are an average of 2500 times smaller than the corresponding GBM 3 σ localizations. We identify four bursts in the IPN/GBM sample whose origins were given as “uncertain,” but may in fact be cosmic. This leads to an estimate of over 99% completeness for the GBM catalog.

CXCR4 expression varies significantly among different subtypes of glioblastoma multiforme (GBM) and its low expression or hypermethylation might predict favorable overall survival.

Science.gov (United States)

Ma, Xinlong; Shang, Feng; Zhu, Weidong; Lin, Qingtang

2017-09-01

CXCR4 is an oncogene in glioblastoma multiforme (GBM) but the mechanism of its dysregulation and its prognostic value in GBM have not been fully understood. Bioinformatic analysis was performed by using R2 and the UCSC Xena browser based on data from GSE16011 in GEO datasets and in GBM cohort in TCGA database (TCGA-GBM). Kaplan Meier curves of overall survival (OS) were generated to assess the association between CXCR4 expression/methylation and OS in patients with GBM. GBM patients with high CXCR4 expression had significantly worse 5 and 10 yrs OS (p GBM subtypes, there was an inverse relationship between overall DNA methylation and CXCR4 expression. CXCR4 expression was significantly lower in CpG island methylation phenotype (CIMP) group than in non CIMP group. Log rank test results showed that patients with high CXCR4 methylation (first tertile) had significantly better 5 yrs OS (p = 0.038). CXCR4 expression is regulated by DNA methylation in GBM and its low expression or hypermethylation might indicate favorable OS in GBM patients.

MAXIMIZATION OF DNA DAMAGE TO MGMT(+ EGFR(+ GBM CELLS USING OPTIMAL COMBINATION OF TEMOZOLOMIDE-ANTI EGFR MONOCLONAL ANTIBODY NIMOTUZUMAB

Directory of Open Access Journals (Sweden)

M. A. M. Inggas

2015-09-01

Full Text Available Background: Glioblastoma multiforme (GBM is the most aggressive primary brain tumor in adultswith dismal prognosis due to the unavailability of an effective therapy. Up to now, there had been no definitive studies published on EGFR inhibition therapy as a chemosensitizer for GBM therapy using Temozolomide (TMZ. This study aims to reveal the most effective method and timing to administer TMZ-anti EGFR targeted therapy which causes maximal DNA damage on GBM cells.Methods: Various regimens of anti EGFR monoclonal antibody Nimotuzumab (NMZ was administered in different combinations with TMZ, performed on U87MG MGMT(+ EGFR(+ cells. The effectiveness of the combinations were evaluated by measuring yH2AX levels which reflects the degree of DNA damage. One-way Anova and LSD tests were performed to determine the effects of each treatment with p<0.05. Results and discussion: the mean SD of yH2AX of each treatment was: 11,90±1,25 for the control group; 29.33±1.91 for NMZ alone; 28.13±1.58 for TMZ alone; 41.53±3.51 for concurrent use; 35.67 ±2.65 for NMZ after 24 hours TMZ; 31.87±2.94 for NMZ after 48 hours TMZ; 39.57±4.2 for TMZ after 24 hours NMZ; and 35.93 ±3.56 for TMZ after 48 hours NMZ. The administration of TMZ concurrent with or after 24 hours NMZ gives the highest amount of DNA damage to GBM cells. Conclusion: The administration of Nimotuzumab targeted therapy up to 24 hours before Temozolomide chemotherapy has been proven to be effective in maximizing the amount of DNA damage done to GBM cells in vitro. 

Ultrastructural characterization of primary cilia in pathologically characterized human glioblastoma multiforme (GBM) tumors.

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Moser, Joanna J; Fritzler, Marvin J; Rattner, Jerome B

2014-01-01

Primary cilia are non-motile sensory cytoplasmic organelles that are involved in cell cycle progression. Ultrastructurally, the primary cilium region is complex, with normal ciliogenesis progressing through five distinct morphological stages in human astrocytes. Defects in early stages of ciliogenesis are key features of astrocytoma/glioblastoma cell lines and provided the impetus for the current study which describes the morphology of primary cilia in molecularly characterized human glioblastoma multiforme (GBM) tumors. Seven surgically resected human GBM tissue samples were molecularly characterized according to IDH1/2 mutation status, EGFR amplification status and MGMT promoter methylation status and were examined for primary cilia expression and structure using indirect immunofluorescence and electron microscopy. We report for the first time that primary cilia are disrupted in the early stages of ciliogenesis in human GBM tumors. We confirm that immature primary cilia and basal bodies/centrioles have aberrant ciliogenesis characteristics including absent paired vesicles, misshaped/swollen vesicular hats, abnormal configuration of distal appendages, and discontinuity of centriole microtubular blades. Additionally, the transition zone plate is able to form in the absence of paired vesicles on the distal end of the basal body and when a cilium progresses beyond the early stages of ciliogenesis, it has electron dense material clumped along the transition zone and a darkening of the microtubules at the proximal end of the cilium. Primary cilia play a role in a variety of human cancers. Previously primary cilia structure was perturbed in cultured cell lines derived from astrocytomas/glioblastomas; however there was always some question as to whether these findings were a cell culture phenomena. In this study we confirm that disruptions in ciliogenesis at early stages do occur in GBM tumors and that these ultrastructural findings bear resemblance to those previously

Tamoxifen in combination with temozolomide induce a synergistic inhibition of PKC-pan in GBM cell lines.

Science.gov (United States)

Balça-Silva, Joana; Matias, Diana; do Carmo, Anália; Girão, Henrique; Moura-Neto, Vivaldo; Sarmento-Ribeiro, Ana Bela; Lopes, Maria Celeste

2015-04-01

Glioblastoma (GBM) is a highly proliferative, angiogenic grade IV astrocytoma that develops resistance to the alkylating agents used in chemotherapy, such as temozolomide (TMZ), which is considered the gold standard. The mean survival time for GBM patients is approximately 12 months, increasing to 14.6 months after TMZ treatment. The resistance of GBM to chemotherapy seems to be associated to genetic alterations and to the constitutive activation of several signaling pathways. Therefore, the combination of different drugs with different mechanisms of action may contribute to circumvent the chemoresistance of glioma cells. Here we describe the potential synergistic behavior of the therapeutic combination of tamoxifen (TMX), a known inhibitor of PKC, and TMZ in GBM. We used two GBM cell lines incubated in absence and presence of TMX and/or TMZ and measured cell viability, proliferation, apoptosis, cell cycle, migration ability, cytoskeletal organization and the phosphorylated amount of the p-PKC-pan. The combination of low doses of TMX with increasing doses of TMZ shows an increased antiproliferative and apoptotic effect compared to the effect with TMX alone. The combination of TMX and TMZ seems to potentiate the effect of each other. These alterations seem to be associated to a decrease in the phosphorylation status of PKC. We emphasize that TMX is an inhibitor of the p-PKC-pan and that these combination is more effective in the reduction of proliferation and in the increase of apoptosis than each drug alone, which presents a new therapeutic strategy in GBM treatment. Copyright © 2014 Elsevier B.V. All rights reserved.

MGMT inactivation and clinical response in newly diagnosed GBM patients treated with Gliadel.

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Grossman, Rachel; Burger, Peter; Soudry, Ethan; Tyler, Betty; Chaichana, Kaisorn L; Weingart, Jon; Olivi, Alessandro; Gallia, Gary L; Sidransky, David; Quiñones-Hinojosa, Alfredo; Ye, Xiaobu; Brem, Henry

2015-12-01

We examined the relationship between the O(6)-methylguanine-methyltransferase (MGMT) methylation status and clinical outcomes in newly diagnosed glioblastoma multiforme (GBM) patients who were treated with Gliadel wafers (Eisai, Tokyo, Japan). MGMT promoter methylation has been associated with increased survival among patients with GBM who are treated with various alkylating agents. MGMT promoter methylation, in DNA from 122 of 160 newly diagnosed GBM patients treated with Gliadel, was determined by a quantitative methylation-specific polymerase chain reaction, and was correlated with overall survival (OS) and recurrence-free survival (RFS). The MGMT promoter was methylated in 40 (32.7%) of 122 patients. The median OS was 13.5 months (95% confidence interval [CI] 11.0-14.5) and RFS was 9.4 months (95% CI 7.8-10.2). After adjusting for age, Karnofsky performance score, extent of resection, temozolomide (TMZ) and radiation therapy (RT), the newly diagnosed GBM patients with MGMT methylation had a 15% reduced mortality risk, compared to patients with unmethylated MGMT (hazard ratio 0.85; 95% CI 0.56-1.31; p=0.46). The patients aged over 70 years with MGMT methylation had a significantly longer median OS of 13.5 months, compared to 7.6 months in patients with unmethylated MGMT (p=0.027). A significant difference was also found in older patients, with a median RFS of 13.1 versus 7.6 months for methylated and unmethylated MGMT groups, respectively (p=0.01). Methylation of the MGMT promoter in newly diagnosed GBM patients treated with Gliadel, RT and TMZ, was associated with significantly improved OS compared to the unmethylated population. In elderly patients, methylation of the MGMT promoter was associated with significantly better OS and RFS. Copyright © 2015 Elsevier Ltd. All rights reserved.

Experimental anti-GBM disease as a tool for studying spontaneous lupus nephritis.

Science.gov (United States)

Fu, Yuyang; Du, Yong; Mohan, Chandra

2007-08-01

Lupus nephritis is an immune-mediated disease, where antibodies and T cells both play pathogenic roles. Since spontaneous lupus nephritis in mouse models takes 6-12 months to manifest, there is an urgent need for a mouse model that can be used to delineate the pathogenic processes that lead to immune nephritis, over a quicker time frame. We propose that the experimental anti-glomerular basement membrane (GBM) disease model might be a suitable tool for uncovering some of the molecular steps underlying lupus nephritis. This article reviews the current evidence that supports the use of the experimental anti-GBM nephritis model for studying spontaneous lupus nephritis. Importantly, out of about 25 different molecules that have been specifically examined in the experimental anti-GBM model and also spontaneous lupus nephritis, all influence both diseases concordantly, suggesting that the experimental model might be a useful tool for unraveling the molecular basis of spontaneous lupus nephritis. This has important clinical implications, both from the perspective of genetic susceptibility as well as clinical therapeutics.

TU-AB-BRA-11: Evaluation of Fully Automatic Volumetric GBM Segmentation in the TCGA-GBM Dataset: Prognosis and Correlation with VASARI Features

International Nuclear Information System (INIS)

Rios Velazquez, E; Meier, R; Dunn, W; Gutman, D; Alexander, B; Wiest, R; Reyes, M; Bauer, S; Aerts, H

2015-01-01

Purpose: Reproducible definition and quantification of imaging biomarkers is essential. We evaluated a fully automatic MR-based segmentation method by comparing it to manually defined sub-volumes by experienced radiologists in the TCGA-GBM dataset, in terms of sub-volume prognosis and association with VASARI features. Methods: MRI sets of 67 GBM patients were downloaded from the Cancer Imaging archive. GBM sub-compartments were defined manually and automatically using the Brain Tumor Image Analysis (BraTumIA), including necrosis, edema, contrast enhancing and non-enhancing tumor. Spearman’s correlation was used to evaluate the agreement with VASARI features. Prognostic significance was assessed using the C-index. Results: Auto-segmented sub-volumes showed high agreement with manually delineated volumes (range (r): 0.65 – 0.91). Also showed higher correlation with VASARI features (auto r = 0.35, 0.60 and 0.59; manual r = 0.29, 0.50, 0.43, for contrast-enhancing, necrosis and edema, respectively). The contrast-enhancing volume and post-contrast abnormal volume showed the highest C-index (0.73 and 0.72), comparable to manually defined volumes (p = 0.22 and p = 0.07, respectively). The non-enhancing region defined by BraTumIA showed a significantly higher prognostic value (CI = 0.71) than the edema (CI = 0.60), both of which could not be distinguished by manual delineation. Conclusion: BraTumIA tumor sub-compartments showed higher correlation with VASARI data, and equivalent performance in terms of prognosis compared to manual sub-volumes. This method can enable more reproducible definition and quantification of imaging based biomarkers and has a large potential in high-throughput medical imaging research

TU-AB-BRA-11: Evaluation of Fully Automatic Volumetric GBM Segmentation in the TCGA-GBM Dataset: Prognosis and Correlation with VASARI Features

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Rios Velazquez, E [Dana-Farber Cancer Institute | Harvard Medical School, Boston, MA (United States); Meier, R [Institute for Surgical Technology and Biomechanics, Bern, NA (Switzerland); Dunn, W; Gutman, D [Emory University School of Medicine, Atlanta, GA (United States); Alexander, B [Dana- Farber Cancer Institute, Brigham and Womens Hospital, Harvard Medic, Boston, MA (United States); Wiest, R; Reyes, M [Institute for Surgical Technology and Biomechanics, University of Bern, Bern, NA (Switzerland); Bauer, S [Institute for Surgical Technology and Biomechanics, Support Center for Adva, Bern, NA (Switzerland); Aerts, H [Dana-Farber/Brigham Womens Cancer Center, Boston, MA (United States)

2015-06-15

Purpose: Reproducible definition and quantification of imaging biomarkers is essential. We evaluated a fully automatic MR-based segmentation method by comparing it to manually defined sub-volumes by experienced radiologists in the TCGA-GBM dataset, in terms of sub-volume prognosis and association with VASARI features. Methods: MRI sets of 67 GBM patients were downloaded from the Cancer Imaging archive. GBM sub-compartments were defined manually and automatically using the Brain Tumor Image Analysis (BraTumIA), including necrosis, edema, contrast enhancing and non-enhancing tumor. Spearman’s correlation was used to evaluate the agreement with VASARI features. Prognostic significance was assessed using the C-index. Results: Auto-segmented sub-volumes showed high agreement with manually delineated volumes (range (r): 0.65 – 0.91). Also showed higher correlation with VASARI features (auto r = 0.35, 0.60 and 0.59; manual r = 0.29, 0.50, 0.43, for contrast-enhancing, necrosis and edema, respectively). The contrast-enhancing volume and post-contrast abnormal volume showed the highest C-index (0.73 and 0.72), comparable to manually defined volumes (p = 0.22 and p = 0.07, respectively). The non-enhancing region defined by BraTumIA showed a significantly higher prognostic value (CI = 0.71) than the edema (CI = 0.60), both of which could not be distinguished by manual delineation. Conclusion: BraTumIA tumor sub-compartments showed higher correlation with VASARI data, and equivalent performance in terms of prognosis compared to manual sub-volumes. This method can enable more reproducible definition and quantification of imaging based biomarkers and has a large potential in high-throughput medical imaging research.

Variant allele frequency enrichment analysis in vitro reveals sonic hedgehog pathway to impede sustained temozolomide response in GBM.

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Biswas, Nidhan K; Chandra, Vikas; Sarkar-Roy, Neeta; Das, Tapojyoti; Bhattacharya, Rabindra N; Tripathy, Laxmi N; Basu, Sunandan K; Kumar, Shantanu; Das, Subrata; Chatterjee, Ankita; Mukherjee, Ankur; Basu, Pryiadarshi; Maitra, Arindam; Chattopadhyay, Ansuman; Basu, Analabha; Dhara, Surajit

2015-01-21

Neoplastic cells of Glioblastoma multiforme (GBM) may or may not show sustained response to temozolomide (TMZ) chemotherapy. We hypothesize that TMZ chemotherapy response in GBM is predetermined in its neoplastic clones via a specific set of mutations that alter relevant pathways. We describe exome-wide enrichment of variant allele frequencies (VAFs) in neurospheres displaying contrasting phenotypes of sustained versus reversible TMZ-responses in vitro. Enrichment of VAFs was found on genes ST5, RP6KA1 and PRKDC in cells showing sustained TMZ-effect whereas on genes FREM2, AASDH and STK36, in cells showing reversible TMZ-effect. Ingenuity pathway analysis (IPA) revealed that these genes alter cell-cycle, G2/M-checkpoint-regulation and NHEJ pathways in sustained TMZ-effect cells whereas the lysine-II&V/phenylalanine degradation and sonic hedgehog (Hh) pathways in reversible TMZ-effect cells. Next, we validated the likely involvement of the Hh-pathway in TMZ-response on additional GBM neurospheres as well as on GBM patients, by extracting RNA-sequencing-based gene expression data from the TCGA-GBM database. Finally, we demonstrated TMZ-sensitization of a TMZ non-responder neurosphere in vitro by treating them with the FDA-approved pharmacological Hh-pathway inhibitor vismodegib. Altogether, our results indicate that the Hh-pathway impedes sustained TMZ-response in GBM and could be a potential therapeutic target to enhance TMZ-response in this malignancy.

Selective anti-tumor activity of the novel fluoropyrimidine polymer F10 towards G48a orthotopic GBM tumors.

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Gmeiner, William H; Lema-Tome, Carla; Gibo, Denise; Jennings-Gee, Jamie; Milligan, Carol; Debinski, Waldemar

2014-02-01

F10 is a novel anti-tumor agent with minimal systemic toxicity in vivo and which displays strong cytotoxicity towards glioblastoma (GBM) cells in vitro. Here we investigate the cytotoxicity of F10 towards GBM cells and evaluate the anti-tumor activity of locally-administered F10 towards an orthotopic xenograft model of GBM. The effects of F10 on thymidylate synthase (TS) inhibition and Topoisomerase 1 (Top1) cleavage complex formation were evaluated using TS activity assays and in vivo complex of enzyme bioassays. Cytotoxicity of F10 towards normal brain was evaluated using cortices from embryonic (day 18) mice. F10 displays minimal penetrance of the blood-brain barrier and was delivered by intra-cerebral (i.c.) administration and prospective anti-tumor response towards luciferase-expressing G48a human GBM tumors in nude mice was evaluated using IVIS imaging. Histological examination of tumor and normal brain tissue was used to assess the selectivity of anti-tumor activity. F10 is cytotoxic towards G48a, SNB-19, and U-251 MG GBM cells through dual targeting of TS and Top1. F10 is not toxic to murine primary neuronal cultures. F10 is well-tolerated upon i.c. administration and induces significant regression of G48a tumors that is dose-dependent. Histological analysis from F10-treated mice revealed tumors were essentially completely eradicated in F10-treated mice while vehicle-treated mice displayed substantial infiltration into normal tissue. F10 displays strong efficacy for GBM treatment with minimal toxicity upon i.c. administration establishing F10 as a promising drug-candidate for treating GBM in human patients.

IMPLICATIONS OF THE TENTATIVE ASSOCIATION BETWEEN GW150914 AND A FERMI -GBM TRANSIENT

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Li, Xiang; Yuan, Qiang; Jin, Zhi-Ping; Fan, Yi-Zhong; Liu, Si-Ming; Wei, Da-Ming [Key Laboratory of dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Science, Nanjing 210008 (China); Zhang, Fu-Wen, E-mail: yzfan@pmo.ac.cn, E-mail: dmwei@pmo.ac.cn, E-mail: fwzhang@glut.edu.cn [College of Science, Guilin University of Technology, Guilin 541004 (China)

2016-08-10

The merger-driven gamma-ray bursts (GRBs) and their associated gravitational-wave (GW) radiation, if both are successfully detected, have some far-reaching implications, including, for instance: (i) the statistical comparison of the physical properties of the short/long-short GRBs with and without GW detection can test the general origin model; (ii) revealing the physical processes taking place at the central engine; (iii) measuring the velocity of the gravitational wave directly/accurately. In this work, we discuss these implications in the case of a possible association of GW150914/Gamma-ray Burst Monitor (GBM) transient 150914. We compared GBM transient 150914 with other SGRBs and found that such an event may be a distinct outlier in some statistical diagrams, possibly due to its specific binary black hole merger origin. However, the presence of a “new” group of SGRBs with “unusual” physical parameters is also possible. If the outflow of GBM transient 150914 was launched by the accretion onto the nascent black hole, the magnetic activity rather than the neutrino process is likely responsible for the energy extraction, and the accretion disk mass is estimated to be ∼10{sup −5} M {sub ⊙}. The GW150914/GBM transient 150914 association, if confirmed, would provide the first opportunity to directly measure the GW velocity, and its departure from the speed of the light should be within a factor of ∼10{sup −17}.

Immunoadsorption in Anti-GBM Glomerulonephritis: Case Report in a Child and Literature Review.

Science.gov (United States)

Dorval, Guillaume; Lion, Mathilde; Guérin, Sophie; Krid, Saoussen; Galmiche-Rolland, Louise; Salomon, Rémi; Boyer, Olivia

2017-11-01

Antiglomerular basement membrane glomerulonephritis (anti-GBM GN) is a rare autoimmune disease that is characterized by rapidly progressive glomerulonephritis that may be associated with pulmonary hemorrhage. Anti-GBM GN is caused by autoantibodies (classically type G immunoglobulin) directed against the α3 subunit of type IV collagen. Without any appropriate treatment, the disease is generally fulminant, and patient and kidney survival is poor. The current guidelines recommend the use of plasma exchanges and immunosuppressive drugs. Immunoadsorption (IA) can remove pathogenic IgGs from the circulation and do not require plasma infusions, contrary to plasma exchanges. IA has seldom been used in adult patients with good tolerance and efficiency. We report herein the first pediatric case successfully treated with IA combined with immunosuppressive drugs in a 7-year-old girl who presented acute kidney injury (estimated glomerular filtration rate 38 mL/minute/1.73 m 2 ). A kidney biopsy revealed numerous >80% glomerular crescents and linear IgG deposits along the glomerular basement membrane. Ten IA sessions led to rapid and sustained clearance of autoantibodies and improvement of kidney function until 21 months after onset (glomerular filtration rate 87 mL/minute/1.73 m 2 ). No adverse effect was noted. This report adds to the growing body of evidence suggesting IA as a therapeutic alternative to plasma exchanges in anti-GBM GN. The other 27 published pediatric cases of anti-GBM GN are reviewed. Copyright © 2017 by the American Academy of Pediatrics.

Study Protocol: Early Stereotactic Gamma Knife Radiosurgery to Residual Tumor After Surgery of Newly Diagnosed Glioblastoma (Gamma-GBM).

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Brehmer, Stefanie; Grimm, Mario Alexander; Förster, Alex; Seiz-Rosenhagen, Marcel; Welzel, Grit; Stieler, Florian; Wenz, Frederik; Groden, Christoph; Mai, Sabine; Hänggi, Daniel; Giordano, Frank Anton

2018-04-24

Glioblastoma (GBM) is the most common malignant brain tumor in adult patients. Tumor recurrence commonly occurs around the resection cavity, especially after subtotal resection (STR). Consequently, the extent of resection correlates with overall survival (OS), suggesting that depletion of postoperative tumor remnants will improve outcome. To assess safety and efficacy of adding stereotactic radiosurgery (SRS) to the standard treatment of GBM in patients with postoperative residual tumor. Gamma-GBM is a single center, open-label, prospective, single arm, phase II study that includes patients with newly diagnosed GBM (intraoperative via frozen sections) who underwent STR (residual tumor will be identified by native and contrast enhanced T1-weighted magnetic resonance imaging scans). All patients will receive SRS with 15 Gy (prescribed to the 50% isodose enclosing all areas of residual tumor) early (within 24-72 h) after surgery. Thereafter, all patients undergo standard-of-care therapy for GBM (radiochemotherapy with 60 Gy external beam radiotherapy [EBRT] plus concomitant temozolomide and 6 cycles of adjuvant temozolomide chemotherapy). The primary outcome is median progression-free survival, secondary outcomes are median OS, occurrence of radiation induced acute (3 mo post-SRS) neurotoxicity and incidence of symptomatic radionecrosis. We expect to detect efficacy and safety signals by the immediate application of SRS to standard-of-care therapy in newly diagnosed GBM. Early postoperative SRS to areas of residual tumor could bridge the therapeutic gap between surgery and adjuvant therapies.

Predictors of renal and patient outcomes in anti-GBM disease: clinicopathologic analysis of a two-centre cohort.

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Alchi, Bassam; Griffiths, Meryl; Sivalingam, Murugan; Jayne, David; Farrington, Ken

2015-05-01

Patients with anti-glomerular basement membrane (GBM) disease are at increased risk of morbidity and mortality from renal failure, pulmonary haemorrhage or complications of treatment. One-third also have circulating anti-neutrophil cytoplasmic antibodies (ANCA). The aim of this study was to determine the clinicopathologic predictors of patient and renal outcomes in anti-GBM disease with or without ANCA. Retrospective review of 43 patients diagnosed with anti-GBM disease over 20 years in two centres, including nine with dual anti-GBM and ANCA positivity. Renal biopsies from 27 patients were scored for the presence of active and chronic lesions. Dual-positive patients were almost 20 years older than those with anti-GBM positivity alone (P = 0.003). The overall 1-year patient and renal survivals were 88 and 16%, respectively. Oligoanuria at diagnosis was the strongest predictor of mortality; none of the 16 patients without oligoanuria died. In a Cox regression model excluding oligoanuria, age was the only other independent predictor of survival. Pulmonary haemorrhage and dialysis dependence did not influence mortality. Thirty-five of the forty-three (81%) patients required dialysis at presentation, including all nine dual-positive patients. Of them, only two (5.7%) regained renal function at 1 year. By logistic regression, oligoanuria at diagnosis and percentage of crescents were independent predictors of dialysis independence at 3 months. However, in biopsied patients, the presence of crescents (>75%) added little to the presence of oligoanuria in predicting dialysis independence. Histological activity and chronicity indices did not predict renal outcome. Two of the nine (22%) dual-positive patients relapsed compared with none of the anti-GBM alone patients. Seven patients received kidney transplants without disease recurrence. Oligoanuria is the strongest predictor of patient and renal survival while percentage of glomerular crescents is the only pathologic

Low level neutron monitoring using high pressure 3He detectors

International Nuclear Information System (INIS)

Pszona, S.

1995-01-01

Three detectors, two spherical proportional counters and an ionisation chamber, all filled with 3 He to pressures of 160 kPa, 325 kPa and 1 MPa respectively have been experimentally studied with respect to their use for low level neutron monitoring. The ambient dose equivalent responses and the energy resolutions of these detectors have been determined. It is shown that spectral analysis of the signals from these detectors not only gives high sensitivity with regard to ambient dose equivalent but also improves the quality of the measurements. A special instrumentation for low level neutron monitoring is described in which a quality control method has been implemented. (Author)

Fermi GBM Observations of Terrestrial Gamma-Ray Flashes

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Wilson-Hodge, Colleen A.; Briggs, M. S.; Connaughton, V.; Fishman, G. J.; Bhat, P. N.; Paciesas, W. S.; Preece, R.; Kippen, R. M.; vonKienlin, A.; Dwyer, J. R.;

Glioblastoma multiforme (GBM) in the elderly: initial treatment strategy and overall survival.

Science.gov (United States)

Glaser, Scott M; Dohopolski, Michael J; Balasubramani, Goundappa K; Flickinger, John C; Beriwal, Sushil

2017-08-01

The EORTC trial which solidified the role of external beam radiotherapy (EBRT) plus temozolomide (TMZ) in the management of GBM excluded patients over age 70. Randomized studies of elderly patients showed that hypofractionated EBRT (HFRT) alone or TMZ alone was at least equivalent to conventionally fractionated EBRT (CFRT) alone. We sought to investigate the practice patterns and survival in elderly patients with GBM. We identified patients age 65-90 in the National Cancer Data Base (NCDB) with histologically confirmed GBM from 1998 to 2012 and known chemotherapy and radiotherapy status. We analyzed factors predicting treatment with EBRT alone vs. EBRT plus concurrent single-agent chemotherapy (CRT) using multivariable logistic regression. Similarly, within the EBRT alone cohort we compared CFRT (54-65 Gy at 1.7-2.1 Gy/fraction) to HFRT (34-60 Gy at 2.5-5 Gy/fraction). Multivariable Cox proportional hazards model (MVA) with propensity score adjustment was used to compare survival. A total of 38,862 patients were included. Initial treatments for 1998 versus 2012 were: EBRT alone = 50 versus 10%; CRT = 6 versus 50%; chemo alone = 1.6% (70% single-agent) versus 3.2% (94% single-agent). Among EBRT alone patients, use of HFRT (compared to CFRT) increased from 13 to 41%. Numerous factors predictive for utilization of CRT over EBRT alone and for HFRT over CFRT were identified. Median survival and 1-year overall survival were higher in the CRT versus EBRT alone group at 8.6 months vs. 5.1 months and 36.0 versus 15.7% (p GBM patients in the United States, CRT is the most common initial treatment and appears to offer a survival advantage over EBRT alone. Adoption of hypofractionation has increased over time but continues to be low.

SOCS3 promoter hypermethylation is a favorable prognosticator and a novel indicator for G-CIMP-positive GBM patients.

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Feng, Ying; Wang, Zheng; Bao, Zhaoshi; Yan, Wei; You, Gan; Wang, Yinyan; Hu, Huimin; Zhang, Wei; Zhang, Quangeng; Jiang, Tao

2014-01-01

Hypermethylation of the suppressor of cytokine signaling 3(SOCS3) promoter has been reported to predict a poor prognosis in several cancers including glioblastoma multiforme (GBM). We explored the function of SOCS3 promoter hypermethylation in GBM cohorts, including analysis of the CpG island methylator phenotype (CIMP), when a large number of gene loci are simultaneously hypermethylated. A whole genome promoter methylation profile was performed in a cohort of 33 GBM samples, with 13 long-term survivors (LTS; overall survival ≥ 18 months) and 20 short-term survivors (STS; overall survival ≤ 9 months). The SOCS3 promoter methylation status was compared between the two groups. In addition, we investigated the relationship of SOCS3 promoter methylation and G-CIMP status. Interestingly, in our present study, we found that SOCS3 promoter methylation was statistically significantly higher in the 13 LTS than that in the 20 STS. Furthermore, high SOCS3 promoter methylation detected via pyro-sequencing predicted a better prognosis in an independent cohort containing 62 GBM patients. This correlation was validated by the dataset from the Cancer Genome Atlas(TCGA) and the Chinese Cancer Genome Atlas(CGGA). In addition, we found that hypermethylation of the SOCS3 promoter was tightly associated with the G-CIMP-positive GBM patients. Using a total of 359 clinical samples, we demonstrate that SOCS3 promoter hypermethylation status has a favorable prognostic value in GBM patients because of whole genome methylation status. Particularly, the hypermethylation of the SOCS3 promoter indicates positive G-CIMP status.

SOCS3 promoter hypermethylation is a favorable prognosticator and a novel indicator for G-CIMP-positive GBM patients.

Directory of Open Access Journals (Sweden)

Ying Feng

Full Text Available Hypermethylation of the suppressor of cytokine signaling 3(SOCS3 promoter has been reported to predict a poor prognosis in several cancers including glioblastoma multiforme (GBM. We explored the function of SOCS3 promoter hypermethylation in GBM cohorts, including analysis of the CpG island methylator phenotype (CIMP, when a large number of gene loci are simultaneously hypermethylated.A whole genome promoter methylation profile was performed in a cohort of 33 GBM samples, with 13 long-term survivors (LTS; overall survival ≥ 18 months and 20 short-term survivors (STS; overall survival ≤ 9 months. The SOCS3 promoter methylation status was compared between the two groups. In addition, we investigated the relationship of SOCS3 promoter methylation and G-CIMP status.Interestingly, in our present study, we found that SOCS3 promoter methylation was statistically significantly higher in the 13 LTS than that in the 20 STS. Furthermore, high SOCS3 promoter methylation detected via pyro-sequencing predicted a better prognosis in an independent cohort containing 62 GBM patients. This correlation was validated by the dataset from the Cancer Genome Atlas(TCGA and the Chinese Cancer Genome Atlas(CGGA. In addition, we found that hypermethylation of the SOCS3 promoter was tightly associated with the G-CIMP-positive GBM patients.Using a total of 359 clinical samples, we demonstrate that SOCS3 promoter hypermethylation status has a favorable prognostic value in GBM patients because of whole genome methylation status. Particularly, the hypermethylation of the SOCS3 promoter indicates positive G-CIMP status.

Proteolysis breaks tolerance toward intact α345(IV) collagen, eliciting novel anti-GBM autoantibodies specific for α345NC1 hexamers

Science.gov (United States)

Olaru, Florina; Wang, Xu-Ping; Luo, Wentian; Ge, Linna; Miner, Jeffrey H; Kleinau, Sandra; Geiger, Xochiquetzal J.; Wasiluk, Andrew; Heidet, Laurence; Kitching, A. Richard; Borza, Dorin-Bogdan

2012-01-01

Goodpasture disease is an autoimmune kidney disease mediated by autoAbs against NC1 monomers of α3(IV) collagen that bind to the glomerular basement membrane (GBM), usually causing rapidly progressive glomerulonephritis. We identified a novel type of human IgG4-restricted anti-GBM autoAbs associated with mild non-progressive glomerulonephritis, which specifically targeted α345NC1 hexamers but not α3NC1 monomers. The mechanisms eliciting these anti-GBM autoAbs were investigated in mouse models recapitulating this phenotype. Wild type and FcγRIIB−/− mice immunized with autologous murine GBM NC1 hexamers produced mouse IgG1-restricted autoAbs specific for α345NC1 hexamers, which bound to the GBM in vivo but did not cause glomerulonephritis. In these mice, intact collagen IV from murine GBM was not immunogenic. However, in Col4a3−/− Alport mice, both intact collagen IV and NC1 hexamers from murine GBM elicited IgG antibodies specific for α3α4α5NC1 hexamers, which were not subclass restricted. As heterologous antigen in COL4A3-humanized mice, murine GBM NC1 hexamers elicited mouse IgG1, IgG2a and IgG2b autoAbs specific for α345NC1 hexamers and induced anti-GBM Ab glomerulonephritis. These findings indicate that tolerance toward autologous intact α3α4α5(IV) collagen is established in hosts expressing this antigen, even though autoreactive B cells specific for α345NC1 hexamers are not purged from their repertoire. Proteolysis selectively breaches this tolerance by generating autoimmunogenic α3α4α5NC1 hexamers. This provides a mechanism eliciting autoAbs specific for α345NC1 hexamers, which are restricted to non-inflammatory IgG subclasses and non-nephritogenic. In Alport syndrome, lack of tolerance toward α3α4α5(IV) collagen promotes production of alloantibodies to α345NC1 hexamers, including pro-inflammatory IgG subclasses which mediate post-transplant anti-GBM nephritis. PMID:23303673

Overview of Green Building Material (GBM Policies and Guidelines with Relevance to Indoor Air Quality Management in Taiwan

Directory of Open Access Journals (Sweden)

Wen-Tien Tsai

2017-12-01

Full Text Available The objective of this paper was to offer a preliminary overview of Taiwan’s success in green building material (GBM efforts through legal systems and promotion measures, which are relevant to the contribution to indoor air quality (IAQ due to sustainability and health issues. In the first part of the paper, the IAQ regulations are summarized to highlight the second nation (i.e., Taiwan around the world in IAQ management by the law. In addition, the permissible exposure limits (PEL in Taiwan for airborne hazardous substances were first promulgated in 1974 to deal with occupational health issues in the workplace environment. In the second part of the paper, the developing status of the GBM in Taiwan is analyzed to unravel its connection with the Indoor Air Quality Management Act (IAQMA, promulgated on 23 November 2011. By the end of September 2017, a total of 645 GBM labels have been conferred, covering over 5000 green products. Due to the effectiveness of source control, the healthy GBM occupies most of the market, accounting for about 75%. The IAQMA, which took force in November 2012, is expected to significantly increase the use of healthy GBM in new building construction and remodeling, especially in low formaldehyde (HCHO/volatile organic compound (VOC-emitting products.

Fermi GBM: Highlights from the First Year

Science.gov (United States)

Wilson-Hodge, Colleen A.

2009-01-01

The Fermi Gamma ray Burst Monitor is an all-sky instrument sensitive to photons from about 8 keV to 40 MeV. I will summarize highlights from the first year, including triggered observations of gamma ray bursts, soft gamma ray repeaters, and terrestrial gamma flashes, and observations in the continuous data of X-ray binaries and accreting X-ray pulsars. GBM provides complementary observations to Swift/BAT, observing many of the same sources, but over a wider energy range.

A low-latency pipeline for GRB light curve and spectrum using Fermi/GBM near real-time data

Science.gov (United States)

Zhao, Yi; Zhang, Bin-Bin; Xiong, Shao-Lin; Long, Xi; Zhang, Qiang; Song, Li-Ming; Sun, Jian-Chao; Wang, Yuan-Hao; Li, Han-Cheng; Bu, Qing-Cui; Feng, Min-Zi; Li, Zheng-Heng; Wen, Xing; Wu, Bo-Bing; Zhang, Lai-Yu; Zhang, Yong-Jie; Zhang, Shuang-Nan; Shao, Jian-Xiong

2018-05-01

Rapid response and short time latency are very important for Time Domain Astronomy, such as the observations of Gamma-ray Bursts (GRBs) and electromagnetic (EM) counterparts of gravitational waves (GWs). Based on near real-time Fermi/GBM data, we developed a low-latency pipeline to automatically calculate the temporal and spectral properties of GRBs. With this pipeline, some important parameters can be obtained, such as T 90 and fluence, within ∼ 20 min after the GRB trigger. For ∼ 90% of GRBs, T 90 and fluence are consistent with the GBM catalog results within 2σ errors. This pipeline has been used by the Gamma-ray Bursts Polarimeter (POLAR) and the Insight Hard X-ray Modulation Telescope (Insight-HXMT) to follow up the bursts of interest. For GRB 170817A, the first EM counterpart of GW events detected by Fermi/GBM and INTEGRAL/SPI-ACS, the pipeline gave T 90 and spectral information 21 min after the GBM trigger, providing important information for POLAR and Insight-HXMT observations.

Fuel cell serves as oxygen level detector

Science.gov (United States)

1965-01-01

Monitoring the oxygen level in the air is accomplished by a fuel cell detector whose voltage output is proportional to the partial pressure of oxygen in the sampled gas. The relationship between output voltage and partial pressure of oxygen can be calibrated.

The Clinical and Immunologic Features of Patients With Combined Anti-GBM Disease and Castleman Disease.

Science.gov (United States)

Gu, Qiu-Hua; Jia, Xiao-Yu; Hu, Shui-Yi; Wang, Su-Xia; Zou, Wan-Zhong; Cui, Zhao; Zhao, Ming-Hui

2018-06-01

Patients with both anti-glomerular basement membrane (anti-GBM) disease and Castleman disease have been rarely reported. In this study, we report 3 patients with this combination. They had immunologic features similar to patients with classic anti-GBM disease. Sera from the 3 patients recognized the noncollagenous (NC) domain of the α3 chain of type IV collagen (α3(IV)NC1) and its 2 major epitopes, EA and EB. All 4 immunogloblin G (IgG) subclasses against α3(IV)NC1 were detectable, with predominance of IgG1. In one patient with lymph node biopsy specimens available, sporadic plasma cells producing α3(IV)NC1-IgG were found, suggesting a causal relationship between the 2 diseases. One patient, who achieved remission with antibody clearance and normalization of serum creatinine and interleukin 6 concentrations after plasma exchange and 3 cycles of chemotherapy, experienced recurrence of anti-GBM antibodies and an increase in interleukin 6 concentration after chemotherapy discontinuation because of adverse effects, but both returned to normal after another cycle of chemotherapy. This clinical course and the pathologic findings support the hypothesis that the Castleman disease-associated tumor cells are the source of the anti-GBM autoantibodies. Copyright © 2018 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Silicon for ultra-low-level detectors and sup 32 Si

Energy Technology Data Exchange (ETDEWEB)

Plaga, R. (Max Planck Inst. fuer Kernphysik, Heidelberg (Germany))

1991-11-15

A recent dark matter experiment using a silicon diode detector confirms that the decay of {sup 32}Si is a dangerous background in ultra-low-level experiments using silicon as detector material or shielding. In this Letter we study the mechanism of how {sup 32}Si enters commercially available silicon. Ways to avoid this contamination are pointed out. Limits on the {sup 32}Si content of silicon from measurements with miniaturized low-level proportional counters are also given. (orig.).

Decreased miR-106a inhibits glioma cell glucose uptake and proliferation by targeting SLC2A3 in GBM.

Science.gov (United States)

Dai, Dong-Wei; Lu, Qiong; Wang, Lai-Xing; Zhao, Wen-Yuan; Cao, Yi-Qun; Li, Ya-Nan; Han, Guo-Sheng; Liu, Jian-Min; Yue, Zhi-Jian

2013-10-14

MiR-106a is frequently down-regulated in various types of human cancer. However the underlying mechanism of miR-106a involved in glioma remains elusive. The association of miR-106a with glioma grade and patient survival was analyzed. The biological function and target of miR-106a were determined by bioinformatic analysis and cell experiments (Western blot, luciferase reporter, cell cycle, ntracellular ATP production and glucose uptake assay). Finally, rescue expression of its target SLC2A3 was used to test the role of SLC2A3 in miR-106a-mediated cell glycolysis and proliferation. Here we showed that miR-106a was a tumor suppressor miRNA was involved in GBM cell glucose uptake and proliferation. Decreased miR-106a in GBM tissues and conferred a poor survival of GBM patients. SLC2A3 was identified as a core target of miR-106a in GBM cells. Inhibition of SLC2A3 by miR-106a attenuated cell proliferation and inhibited glucose uptake. In addition, for each biological process we identified ontology-associated transcripts that significantly correlated with SLC2A3 expression. Finally, the expression of SLC2A3 largely abrogated miR-106a-mediated cell proliferation and glucose uptake in GBM cells. Taken together, miR-106a and SLC2A3 could be potential therapeutic approaches for GBM.

Serial analysis of 3D H-1 MRSI for patients with newly diagnosed GBM treated with combination therapy that includes bevacizumab.

Science.gov (United States)

Nelson, Sarah J; Li, Yan; Lupo, Janine M; Olson, Marram; Crane, Jason C; Molinaro, Annette; Roy, Ritu; Clarke, Jennifer; Butowski, Nicholas; Prados, Michael; Cha, Soonmee; Chang, Susan M

2016-10-01

Interpretation of changes in the T1- and T2-weighted MR images from patients with newly diagnosed glioblastoma (GBM) treated with standard of care in conjunction with anti-angiogenic agents is complicated by pseudoprogression and pseudoresponse. The hypothesis being tested in this study was that 3D H-1 magnetic resonance spectroscopic imaging (MRSI) provides estimates of levels of choline, creatine, N-acetylaspartate (NAA), lactate and lipid that change in response to treatment and that metrics describing these characteristics are associated with survival. Thirty-one patients with newly diagnosed GBM and being treated with radiation therapy (RT), temozolomide, erlotinib and bevacizumab were recruited to receive serial MR scans that included 3-D lactate edited MRSI at baseline, mid-RT, post-RT and at specific follow-up time points. The data were processed to provide estimates of metrics representing changes in metabolite levels relative to normal appearing brain. Cox proportional hazards analysis was applied to examine the relationship of these parameters with progression free survival (PFS) and overall survival (OS). There were significant reductions in parameters that describe relative levels of choline to NAA and creatine, indicating that the treatment caused a decrease in tumor cellularity. Changes in the levels of lactate and lipid relative to the NAA from contralateral brain were consistent with vascular normalization. Metabolic parameters from the first serial follow-up scan were associated with PFS and OS, when accounting for age and extent of resection. Integrating metabolic parameters into the assessment of patients with newly diagnosed GBM receiving therapies that include anti-angiogenic agents may be helpful for tracking changes in tumor burden, resolving ambiguities in anatomic images caused by non-specific treatment effects and for predicting outcome.

Anti-hLAMP2-antibodies and dual positivity for anti-GBM and MPO-ANCA in a patient with relapsing pulmonary-renal syndrome

Directory of Open Access Journals (Sweden)

Kistler Thomas

2011-06-01

Full Text Available Abstract Background Pulmonary-renal syndrome associated with anti-glomerular basement membrane (GBM antibodies, also known as Goodpasture's syndrome, is a rare but acute and life-threatening condition. One third of patients presenting as anti-GBM antibody positive pulmonary-renal syndrome or rapidly progressive glomerulonephritis are also tested positive for anti-neutrophil cytoplasmic antibodies (ANCA. Whilst anti-GBM disease is considered a non-relapsing condition, the long-term course of double-positive patients is less predictable. Case Presentation We report a patient with such dual positivity, who presented with pulmonary hemorrhage, crescentic glomerulonephritis and membranous nephropathy. Plasmapheresis in combination with immunosuppresive therapy led to a rapid remission but the disease relapsed after two years. The serum of the patient was tested positive for antibodies to human lysosomal membrane protein 2 (hLAMP2, a novel autoantigen in patients with active small-vessel vasculitis (SVV. The anti-hLAMP2 antibody levels correlated positively with clinical disease activity in this patient. Conclusion We hypothesize that this antibody may indicate a clinical course similar to ANCA-associated vasculitis in double-positive patients. However, this needs to be confirmed on comprehensive patient cohorts.

Anti-GBM disease after nephrectomy for xanthogranulomatous pyelonephritis in a patient expressing HLA DR15 major histocompatibility antigens: a case report.

Science.gov (United States)

O'Hagan, Emma; Mallett, Tamara; Convery, Mairead; McKeever, Karl

2015-01-01

Antiglomerular basement membrane (anti-GBM) antibody disease is uncommon in the pediatric population. There are no cases in the literature describing the development of anti-GBM disease following XGP or nephrectomy. We report the case of a 7-year-old boy with no past history of urological illness, treated with antimicrobials and nephrectomy for diffuse, unilateral xanthogranulomatous pyelonephritis (XGP). Renal function and ultrasound scan of the contralateral kidney postoperatively were normal. Three months later, the child represented in acute renal failure with rapidly progressive glomerulonephritis requiring hemodialysis. Renal biopsy showed severe crescentic glomerulonephritis with 95% of glomeruli demonstrating circumferential cellular crescents. Strong linear IgG staining of the glomerular basement membranes was present, in keeping with anti-GBM disease. Circulating anti-GBM antibodies were positive. Treatment with plasma exchange, methylprednisolone, and cyclophosphamide led to normalization of anti-GBM antibody titers. Frequency of hemodialysis was reduced as renal function improved, and he is currently independent of dialysis with estimated glomerular filtration rate 20.7 mls/min/1.73 m 2 . Case studies in the adult literature have reported the development of a rapidly progressive anti-GBM antibody-induced glomerulonephritis following renal surgery where patients expressed HLA DR2/HLA DR15 major histocompatibility (MHC) antigens. Of note, our patient also expresses the HLA DR15 MHC antigen.

GBM Observations of Be X-Ray Binary Outbursts

Science.gov (United States)

Wilson-Hodge, Colleen A.; Finger, M. H.; Jenke, P. A.

2014-01-01

Since 2008 we have been monitoring accreting pulsars using the Gamma ray Burst Monitor (GBM) on Fermi. This monitoring program includes daily blind full sky searches for previously unknown or previously quiescent pulsars and source specific analysis to track the frequency evolution of all detected pulsars. To date we have detected outbursts from 23 transient accreting pulsars, including 21 confirmed or likely Be/X-ray binaries. I will describe our techniques and highlight results for selected pulsars.

Development of the liquid level meters for the PandaX dark matter detector

International Nuclear Information System (INIS)

Hu Jie; Gong Haowei; Lin Qing; Ni Kaixuan; Wei Yuehuan; Xiao Mengjiao; Xiao Xiang; Zhao Li; Tan Andi

2014-01-01

The two-phase xenon detector is at the frontier of dark matter direct search. This kind of detector uses liquid xenon as the sensitive target and is operated in two-phase (liquid/gas) mode, where the liquid level needs to be monitored and controlled in sub-millimeter precision. In this paper, we present a detailed design and study of two kinds of level meters for the PandaX dark matter detector. The long level meter is used to monitor the overall liquid level while short level meters are used to monitor the inclination of the detector. These level meters are cylindrical capacitors that are custom-made from two concentric metal tubes. Their capacitance values are read out by a universal transducer interface chip and are recorded by the PandaX slow control system. We present the developments that lead to level meters with long-term stability and sub-millimeter precision. Fluctuations (standard deviations) of less than 0.02 mm for the short level meters and less than 0.2 mm for the long level meter were achieved during a few days of test operation. (authors)

Statistical properties of Fermi GBM GRBs' spectra

Science.gov (United States)

Rácz, István I.; Balázs, Lajos G.; Horvath, Istvan; Tóth, L. Viktor; Bagoly, Zsolt

2018-03-01

Statistical studies of gamma-ray burst (GRB) spectra may result in important information on the physics of GRBs. The Fermi GBM catalogue contains GRB parameters (peak energy, spectral indices, and intensity) estimated fitting the gamma-ray spectral energy distribution of the total emission (fluence, flnc), and during the time of the peak flux (pflx). Using contingency tables, we studied the relationship of the models best-fitting pflx and flnc time intervals. Our analysis revealed an ordering of the spectra into a power law - Comptonized - smoothly broken power law - Band series. This result was further supported by a correspondence analysis of the pflx and flnc spectra categorical variables. We performed a linear discriminant analysis (LDA) to find a relationship between categorical (spectral) and model independent physical data. LDA resulted in highly significant physical differences among the spectral types, that is more pronounced in the case of the pflx spectra, than for the flnc spectra. We interpreted this difference as caused by the temporal variation of the spectrum during the outburst. This spectral variability is confirmed by the differences in the low-energy spectral index and peak energy, between the pflx and flnc spectra. We found that the synchrotron radiation is significant in GBM spectra. The mean low-energy spectral index is close to the canonical value of α = -2/3 during the peak flux. However, α is ˜ -0.9 for the spectra of the fluences. We interpret this difference as showing that the effect of cooling is important only for the fluence spectra.

The front-end (Level-0) electronics interface module for the LHCb RICH detectors

Energy Technology Data Exchange (ETDEWEB)

Adinolfi, M. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Bibby, J.H. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Brisbane, S. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Gibson, V. [Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE (United Kingdom); Harnew, N. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Jones, M. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Libby, J. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom)]. E-mail: j.libby1@physics.ox.ac.uk; Powell, A. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Newby, C. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Rotolo, N. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Smale, N. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Somerville, L.; Sullivan, P.; Topp-Jorgensen, S. [Sub-department of Particle Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Wotton, S. [Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE (United Kingdom); Wyllie, K. [CERN, CH-1211, Geneva 23 (Switzerland)

2007-03-11

The front-end (Level-0) electronics interface module for the LHCb Ring Imaging Cherenkov (RICH) detectors is described. This module integrates the novel hybrid photon detectors (HPDs), which instrument the RICH detectors, to the LHCb trigger, data acquisition (DAQ) and control systems. The system operates at 40 MHz with a first-level trigger rate of 1 MHz. The module design is presented and results are given for both laboratory and beam tests.

The front-end (Level-0) electronics interface module for the LHCb RICH detectors

International Nuclear Information System (INIS)

Adinolfi, M.; Bibby, J.H.; Brisbane, S.; Gibson, V.; Harnew, N.; Jones, M.; Libby, J.; Powell, A.; Newby, C.; Rotolo, N.; Smale, N.; Somerville, L.; Sullivan, P.; Topp-Jorgensen, S.; Wotton, S.; Wyllie, K.

2007-01-01

The front-end (Level-0) electronics interface module for the LHCb Ring Imaging Cherenkov (RICH) detectors is described. This module integrates the novel hybrid photon detectors (HPDs), which instrument the RICH detectors, to the LHCb trigger, data acquisition (DAQ) and control systems. The system operates at 40 MHz with a first-level trigger rate of 1 MHz. The module design is presented and results are given for both laboratory and beam tests

Response assessment of bevacizumab therapy in GBM with integrated 11C-MET-PET/MRI: a feasibility study.

Science.gov (United States)

Deuschl, Cornelius; Moenninghoff, Christoph; Goericke, Sophia; Kirchner, Julian; Köppen, Susanne; Binse, Ina; Poeppel, Thorsten D; Quick, Harald H; Forsting, Michael; Umutlu, Lale; Herrmann, Ken; Hense, Joerg; Schlamann, Marc

2017-08-01

The objective of this study was to evaluate the potential of integrated 11C-MET PET/MR for response assessment of relapsed glioblastoma (GBM) receiving bevacizumab treatment. Eleven consecutive patients with relapsed GBM were enrolled for an integrated 11C-MET PET/MRI at baseline and at follow-up. Treatment response for MRI was evaluated according to Response Assessment in Neuro-oncology (RANO) criteria and integrated 11C-MET PET was assessed by the T/N ratio. MRI showed no patient with complete response (CR), six of 11 patients with PR, four of 11 patients with SD, and one of 11 patients with progressive disease (PD). PET revealed metabolic response in five of the six patients with partial response (PR) and in two of the four patients with stable disease (SD), whereas metabolic non-response was detected in one of the six patients with PR, in two of the four patients with SD, and in the one patient with PD. Morphological imaging was predictive for PFS and OS when response was defined as CR, PR, SD, and non-response as PD. Metabolic imaging was predictive when using T/N ratio reduction of >25 as discriminator. Based on the morphologic and metabolic findings of this study a proposal for applying integrated PET/MRI for treatment response in relapsed GBM was developed, which was significantly predictive for PFS and OS (P = 0.010 respectively 0,029, log). This study demonstrates the potential of integrated 11C-MET-PET/MRI for response assessment of GBM and the utility of combined assessment of morphologic and metabolic information with the proposal for assessing relapsed GBM.

Response assessment of bevacizumab therapy in GBM with integrated 11C-MET-PET/MRI: a feasibility study

Energy Technology Data Exchange (ETDEWEB)

Deuschl, Cornelius [University Hospital Essen, Institute of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); University of Duisburg-Essen, Erwin L. Hahn Institute for Magnetic Resonance Imaging, Duisburg (Germany); Moenninghoff, Christoph; Goericke, Sophia; Forsting, Michael; Umutlu, Lale [University Hospital Essen, Institute of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Kirchner, Julian [University Hospital Duesseldorf, Institute of Diagnostic and Interventional Radiology, Duesseldorf (Germany); Koeppen, Susanne [University Hospital Essen, Department of Neurology, Essen (Germany); Binse, Ina; Poeppel, Thorsten D.; Herrmann, Ken [University Hospital Essen, Department of Nuclear Medicine, Essen (Germany); Quick, Harald H. [University of Duisburg-Essen, Erwin L. Hahn Institute for Magnetic Resonance Imaging, Duisburg (Germany); University Hospital Essen, High Field and Hybrid MR Imaging, Essen (Germany); Hense, Joerg [University Hospital Essen, Department of Medical Oncology, West German Cancer Center, Essen (Germany); Schlamann, Marc [University Hospital Essen, Institute of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); University Hospital Giessen, Department of Neuroradiology, Essen (Germany)

2017-08-15

The objective of this study was to evaluate the potential of integrated 11C-MET PET/MR for response assessment of relapsed glioblastoma (GBM) receiving bevacizumab treatment. Eleven consecutive patients with relapsed GBM were enrolled for an integrated 11C-MET PET/MRI at baseline and at follow-up. Treatment response for MRI was evaluated according to Response Assessment in Neuro-oncology (RANO) criteria and integrated 11C-MET PET was assessed by the T/N ratio. MRI showed no patient with complete response (CR), six of 11 patients with PR, four of 11 patients with SD, and one of 11 patients with progressive disease (PD). PET revealed metabolic response in five of the six patients with partial response (PR) and in two of the four patients with stable disease (SD), whereas metabolic non-response was detected in one of the six patients with PR, in two of the four patients with SD, and in the one patient with PD. Morphological imaging was predictive for PFS and OS when response was defined as CR, PR, SD, and non-response as PD. Metabolic imaging was predictive when using T/N ratio reduction of >25 as discriminator. Based on the morphologic and metabolic findings of this study a proposal for applying integrated PET/MRI for treatment response in relapsed GBM was developed, which was significantly predictive for PFS and OS (P = 0.010 respectively 0,029, log). This study demonstrates the potential of integrated 11C-MET-PET/MRI for response assessment of GBM and the utility of combined assessment of morphologic and metabolic information with the proposal for assessing relapsed GBM. (orig.)

A main amplifier circuit and data acquisition system for charged particle detector array

International Nuclear Information System (INIS)

Hao Rui; Ge Yucheng

2011-01-01

The charged particle detector array has huge amounts of signal and needs high counting rate. To meet the requirements, a main amplifier and analog-to-digital conversion circuit based on high-speed op-amp chips and ADC chip was designed. A 51-MCU was used to control the circuit of ADC and the USB communication chip. The signals were digitized and uploaded by the MCU-ADC-USB circuit. The whole system has a compact hardware structure and a reasonable controlling software, which meet the design requirements. (authors)

The LUCID-2 Detector

CERN Document Server

Sbarra, Carla; The ATLAS collaboration

2018-01-01

LUCID-2 (LUminosity Cherenkov Integrating Detector) is the upgrade of the main detector dedicated to luminosity measurements in ATLAS. Most changes were motivated by the number of interactions per bunch-crossing and the 25 ns bunch-spacing expected in LHC RUN II (2015-2018). Both fast online information used by LHC for luminosity optimisation and levelling in ATLAS, and per-bunch data to be used offline, come from LUCID-2

VizieR Online Data Catalog: New spectral lag measurements of 50 Fermi/GBM GRBs (Shao+, 2017)

Science.gov (United States)

Shao, L.; Zhang, B.-B.; Wang, F.-R.; Wu, X.-F.; Cheng, Y.-H.; Zhang, Xi; Yu, B.-Y.; Xi, B.-J.; Wang, X.; Feng, H.-X.; Zhang, M.; Xu, D.

2018-03-01

This work made extensive use of the data from the Gamma-Ray Burst Monitor (GBM) on board the Fermi Gamma-ray Space Telescope. For the first step, we searched in the official GBM online burst catalog (Gruber+ 2014ApJS..211...12G ; von Kienlin+ 2014, J/ApJS/211/13) for bright bursts with a total fluence F>5x10-6erg/cm-2 in 10-1000keV. See section 2 for the details on the sample selection. (1 data file).

New Electron Cloud Detectors for the PS Main Magnets

CERN Document Server

Yin Vallgren, Ch; Gilardoni, S; Taborelli, M; Neupert, H; Ferreira Somoza, J

2014-01-01

Electron cloud (EC) has already been observed during normal operation of the PS, therefore it is necessary to study its in fluence on any beam instability for the future LHC Injector Upgrade (LIU). Two new electron cloud detectors have been discussed, developed and installed during the Long Shutdown (LS1) in one of the PS main magnets. The first measurement method is based on current measurement by using a shielded button-type pick-up. Due to the geometry and space limitation in the PS magnet, the button-type pick-up made of a 96%Al2O3 block coated with a thin layer of solvent-based Ag painting, placed 30 degrees to the bottom part of the vacuum chamber was installed in the horizontal direction where the only opening of the magnet coil is. The other newly developed measurement method is based on detection of photons emitted by the electrons from the electron cloud impinging on the vacuum chamber walls. The emitted photons are reected to a quartz window. A MCP-PMT (Micro-Channel Plate Photomultiplier Tube) wit...

Detector Systems at CLIC

CERN Document Server

Simon, Frank

2011-01-01

The Compact Linear Collider CLIC is designed to deliver e+e- collisions at a center of mass energy of up to 3 TeV. The detector systems at this collider have to provide highly efficient tracking and excellent jet energy resolution and hermeticity for multi-TeV final states with multiple jets and leptons. In addition, the detector systems have to be capable of distinguishing physics events from large beam-induced background at a crossing frequency of 2 GHz. Like for the detector concepts at the ILC, CLIC detectors are based on event reconstruction using particle flow algorithms. The two detector concepts for the ILC, ILD and SID, were adapted for CLIC using calorimeters with dense absorbers limiting leakage through increased compactness, as well as modified forward and vertex detector geometries and precise time stamping to cope with increased background levels. The overall detector concepts for CLIC are presented, with particular emphasis on the main detector and engineering challenges, such as: the ultra-thi...

Determination of PWR core water level using ex-core detectors signals

International Nuclear Information System (INIS)

Bernal, Alvaro; Abarca, Agustin; Miro, Rafael; Verdu, Gumersindo

2013-01-01

The core water level provides relevant neutronic and thermalhydraulic information of the reactor such as power, k eff and cooling ability; in fact, core water level monitoring could be used to predict LOCA and cooling reduction which may deal with core damage. Although different detection equipment is used to monitor several parameters such as the power, core water level monitoring is not an evident task. However, ex-core detectors can measure the fast neutrons leaking the core and several studies demonstrate the existence of a relationship between fast neutron leakage and core water level due to the shielding effect of the water. In addition, new ex-core detectors are being developed, such as silicon carbide semiconductor radiation detectors, monitoring the neutron flux with higher accuracy and in higher temperatures conditions. Therefore, a methodology to determine this relationship has been developed based on a Monte Carlo calculation using MCNP code and applying variance reduction with adjoint functions based on the adjoint flux obtained with the discrete ordinates code TORT. (author)

Analytical modeling of pulse-pileup distortion using the true pulse shape; applications to Fermi-GBM

International Nuclear Information System (INIS)

Chaplin, Vandiver; Bhat, Narayana; Briggs, Michael S.; Connaughton, Valerie

2013-01-01

Pulse-pileup affects most photon counting systems and occurs when photon detections occur faster than the detector's shaping and recovery time. At high input rates, shaped pulses interfere and the source spectrum, as well as intensity information, get distorted. For instruments using bipolar pulse shaping there are two aspects to consider: ‘peak’ and ‘tail’ pileup effects, which raise and lower the measured energy, respectively. Peak effects have been extensively modeled in the past. Tail effects have garnered less attention due to increased complexity. We leverage previous work to derive an accurate, semi-analytical prediction for peak and tail pileup including high order effects. We use the pulse shape of the detectors of the Fermi Gamma-ray Burst Monitor. The measured spectrum is calculated by expressing exposure time with a state-space expansion of overlapping pileup states and is valid up to very high rates. The model correctly predicts deadtime and pileup losses, and energy-dependent losses due to tail subtraction (sub-threshold) effects. We discuss total losses in terms of the true rate of photon detections versus the recorded count rate. -- Highlights: • A derivation of pulse-pileup spectral and intensity distortion is presented. • Applies to bipolar shaping instruments in general, but is calculated for Fermi-GBM. • Exposure time is partitioned with pulse widths as states of a Poisson process. • Each state has an associated energy distribution function for peak and tail pileup. • The total spectrum is the union of pulse states and their associated spectra

Saponin 1 induces apoptosis and suppresses NF-κB-mediated survival signaling in glioblastoma multiforme (GBM.

Directory of Open Access Journals (Sweden)

Juan Li

Full Text Available Saponin 1 is a triterpeniod saponin extracted from Anemone taipaiensis, a traditional Chinese medicine against rheumatism and phlebitis. It has also been shown to exhibit significant anti-tumor activity against human leukemia (HL-60 cells and human hepatocellular carcinoma (Hep-G2 cells. Herein we investigated the effect of saponin 1 in human glioblastoma multiforme (GBM U251MG and U87MG cells. Saponin 1 induced significant growth inhibition in both glioblastoma cell lines, with a 50% inhibitory concentration at 24 h of 7.4 µg/ml in U251MG cells and 8.6 µg/ml in U87MG cells, respectively. Nuclear fluorescent staining and electron microscopy showed that saponin 1 caused characteristic apoptotic morphological changes in the GBM cell lines. Saponin 1-induced apoptosis was also verified by DNA ladder electrophoresis and flow cytometry. Additionally, immunocytochemistry and western blotting analyses revealed a time-dependent decrease in the expression and nuclear location of NF-κB following saponin 1 treatment. Western blotting data indicated a significant decreased expression of inhibitors of apoptosis (IAP family members,(e.g., survivin and XIAP by saponin 1. Moreover, saponin 1 caused a decrease in the Bcl-2/Bax ratio and initiated apoptosis by activating caspase-9 and caspase-3 in the GBM cell lines. These findings indicate that saponin 1 inhibits cell growth of GBM cells at least partially by inducing apoptosis and inhibiting survival signaling mediated by NF-κB. In addition, in vivo study also demonstrated an obvious inhibition of saponin 1 treatment on the tumor growth of U251MG and U87MG cells-produced xenograft tumors in nude mice. Given the minimal toxicities of saponin 1 in non-neoplastic astrocytes, our results suggest that saponin 1 exhibits significant in vitro and in vivo anti-tumor efficacy and merits further investigation as a potential therapeutic agent for GBM.

Saponin 1 Induces Apoptosis and Suppresses NF-κB-Mediated Survival Signaling in Glioblastoma Multiforme (GBM)

Science.gov (United States)

Tang, Chi; Li, Bo; Wang, Yuangang; Gao, Zhenhui; Luo, Peng; Yin, Anan; Wang, Xiaoyang; Cheng, Guang; Fei, Zhou

2013-01-01

Saponin 1 is a triterpeniod saponin extracted from Anemone taipaiensis, a traditional Chinese medicine against rheumatism and phlebitis. It has also been shown to exhibit significant anti-tumor activity against human leukemia (HL-60 cells) and human hepatocellular carcinoma (Hep-G2 cells). Herein we investigated the effect of saponin 1 in human glioblastoma multiforme (GBM) U251MG and U87MG cells. Saponin 1 induced significant growth inhibition in both glioblastoma cell lines, with a 50% inhibitory concentration at 24 h of 7.4 µg/ml in U251MG cells and 8.6 µg/ml in U87MG cells, respectively. Nuclear fluorescent staining and electron microscopy showed that saponin 1 caused characteristic apoptotic morphological changes in the GBM cell lines. Saponin 1-induced apoptosis was also verified by DNA ladder electrophoresis and flow cytometry. Additionally, immunocytochemistry and western blotting analyses revealed a time-dependent decrease in the expression and nuclear location of NF-κB following saponin 1 treatment. Western blotting data indicated a significant decreased expression of inhibitors of apoptosis (IAP) family members,(e.g., survivin and XIAP) by saponin 1. Moreover, saponin 1 caused a decrease in the Bcl-2/Bax ratio and initiated apoptosis by activating caspase-9 and caspase-3 in the GBM cell lines. These findings indicate that saponin 1 inhibits cell growth of GBM cells at least partially by inducing apoptosis and inhibiting survival signaling mediated by NF-κB. In addition, in vivo study also demonstrated an obvious inhibition of saponin 1 treatment on the tumor growth of U251MG and U87MG cells-produced xenograft tumors in nude mice. Given the minimal toxicities of saponin 1 in non-neoplastic astrocytes, our results suggest that saponin 1 exhibits significant in vitro and in vivo anti-tumor efficacy and merits further investigation as a potential therapeutic agent for GBM. PMID:24278406

Radiation detectors for use in major public events: classification, requirements, main features, tests and lessons learned

Energy Technology Data Exchange (ETDEWEB)

Souza, Elder Magalhães de, E-mail: elder@ird.gov.br [Instituto de Radioproteção e Dosimetria (DIRAD/IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Div. de Radiometria

2017-07-01

Since September 11, 2001, we have entered a new terrorism era. The possibility of the use of lost/stolen radioactive materials increases the probability of a radiological threat. The real goal intended with the use of a Radiological Dispersal Device (RRD or dirty bomb) or a Radiation Exposure Device (RDE) could be psychological in nature. Panic in the venues and surrounding area would cause more deaths than the RDD itself, therefore these attempts could cause chaos, injury, fear and terror, the main target of terrorists. The response of the national authorities with the support and aid of the IAEA served as an increase of the capability of detection and identification of nuclear and radiological materials. But this response could not be limited only to the MPE, because if the country has radioactive or nuclear facilities they also should be considered in terms of theft, sabotage, illegal transfer, unauthorized access, and any other malicious acts. In 2007, Rio de Janeiro, received the first Brazilian Major Public Event in this new era. This was the first Brazilian operation which largely utilized detectors (personal radiations detectors -PRD- radiological identification detectors, -RID or RIID- and spectral radiations scanners, -backpacks-, HPGe detectors, car-borne and air-borne systems) to protect the venues, the athletes, the population and the environment. (author)

Radiation detectors for use in major public events: classification, requirements, main features, tests and lessons learned

International Nuclear Information System (INIS)

Souza, Elder Magalhães de

2017-01-01

Since September 11, 2001, we have entered a new terrorism era. The possibility of the use of lost/stolen radioactive materials increases the probability of a radiological threat. The real goal intended with the use of a Radiological Dispersal Device (RRD or dirty bomb) or a Radiation Exposure Device (RDE) could be psychological in nature. Panic in the venues and surrounding area would cause more deaths than the RDD itself, therefore these attempts could cause chaos, injury, fear and terror, the main target of terrorists. The response of the national authorities with the support and aid of the IAEA served as an increase of the capability of detection and identification of nuclear and radiological materials. But this response could not be limited only to the MPE, because if the country has radioactive or nuclear facilities they also should be considered in terms of theft, sabotage, illegal transfer, unauthorized access, and any other malicious acts. In 2007, Rio de Janeiro, received the first Brazilian Major Public Event in this new era. This was the first Brazilian operation which largely utilized detectors (personal radiations detectors -PRD- radiological identification detectors, -RID or RIID- and spectral radiations scanners, -backpacks-, HPGe detectors, car-borne and air-borne systems) to protect the venues, the athletes, the population and the environment. (author)

Direction Dependent Background Fitting for the Fermi GBM Data

OpenAIRE

Szécsi, Dorottya; Bagoly, Zsolt; Kóbori, József; Horváth, István; Balázs, Lajos G.

2013-01-01

We present a method for determining the background of Fermi GBM GRBs using the satellite positional information and a physical model. Since the polynomial fitting method typically used for GRBs is generally only indicative of the background over relatively short timescales, this method is particularly useful in the cases of long GRBs or those which have Autonomous Repoint Request (ARR) and a background with much variability on short timescales. We give a Direction Dependent Background Fitting...

SU-F-R-04: Radiomics for Survival Prediction in Glioblastoma (GBM)

Energy Technology Data Exchange (ETDEWEB)

Zhang, H; Molitoris, J; Bhooshan, N; Choi, W; Lu, W; Mehta, M; D’Souza, W [University of Maryland School of Medicine, Baltimore, MD (United States); Tan, S [Huazhong University of Science & Technology, Wuhan (China); Giacomelli, I; Scartoni, D [University of Florence, Florence (Italy); Gzell, C [Northern Sydney Cancer Centre, Sydney (Australia)

2016-06-15

Purpose: To develop a quantitative radiomics approach for survival prediction of glioblastoma (GBM) patients treated with chemoradiotherapy (CRT). Methods: 28 GBM patients who received CRT at our institution were retrospectively studied. 255 radiomic features were extracted from 3 gadolinium-enhanced T1 weighted MRIs for 2 regions of interest (ROIs) (the surgical cavity and its surrounding enhancement rim). The 3 MRIs were at pre-treatment, 1-month and 3-month post-CRT. The imaging features comprehensively quantified the intensity, spatial variation (texture), geometric property and their spatial-temporal changes for the 2 ROIs. 3 demographics features (age, race, gender) and 12 clinical parameters (KPS, extent of resection, whether concurrent temozolomide was adjusted/stopped and radiotherapy related information) were also included. 4 Machine learning models (logistic regression (LR), support vector machine (SVM), decision tree (DT), neural network (NN)) were applied to predict overall survival (OS) and progression-free survival (PFS). The number of cases and percentage of cases predicted correctly were collected and AUC (area under the receiver operating characteristic (ROC) curve) were determined after leave-one-out cross-validation. Results: From univariate analysis, 27 features (1 demographic, 1 clinical and 25 imaging) were statistically significant (p<0.05) for both OS and PFS. Two sets of features (each contained 24 features) were algorithmically selected from all features to predict OS and PFS. High prediction accuracy of OS was achieved by using NN (96%, 27 of 28 cases were correctly predicted, AUC = 0.99), LR (93%, 26 of 28 cases were correctly predicted, AUC = 0.95) and SVM (93%, 26 of 28 cases were correctly predicted, AUC = 0.90). When predicting PFS, NN obtained the highest prediction accuracy (89%, 25 of 28 cases were correctly predicted, AUC = 0.92). Conclusion: Radiomics approach combined with patients’ demographics and clinical parameters can

The LUCID-2 Detector

CERN Document Server

Sbarra, Carla; The ATLAS collaboration

2018-01-01

LUCID-2 (LUminosity Cherenkov Integrating Detector) is the upgrade of the main detector dedicated to luminosity monitoring and measurements in the ATLAS Experiment at CERN. Most changes were motivated by the large (up to 50) number of interactions per bunch-crossing and short (25 ns) bunch-spacing expected in LHC run 2 (2015-2018). Both fast online information used by LHC for luminosity optimisation and levelling in ATLAS, and per-bunch data to be used offline, come from LUCID-2.

Low frequency noise in semiconductor detectors

International Nuclear Information System (INIS)

Stojanovic, M.; Marjanovic, N.

1998-01-01

Noise characteristics of surface-barrier detectors based on Au contacts on n-Si were measured and analyzed. The metal layers were deposited by evaporation to 40-100 nm thickness. Standard surface-barrier detectors based on Au/Si structures are known to have favorable characteristics, but they tend to degrade with aging and under severe working conditions. Degradation is particularly related to the increase in noise level, leakage current and the reduction of detector efficiency and resolution. Therefore, practical applications of surface-barrier detectors demand their constant upgrading. Improvements of detector properties are concentrated mainly on the front surface and front (rectifying) contact. The aim was to improve the noise characteristics of the surface-barrier structures and retain the favorable detector properties of the Au/Si system. (authors)

Instrumentation of a Level-1 Track Trigger in the ATLAS detector for the High Luminosity LHC

CERN Document Server

Boisvert, V; The ATLAS collaboration

2012-01-01

One of the main challenges in particle physics experiments at hadron colliders is to build detector systems that can take advantage of the future luminosity increase that will take place during the next decade. More than 200 simultaneous collisions will be recorded in a single event which will make the task to extract the interesting physics signatures harder than ever before. Not all events can be recorded hence a fast trigger system is required to select events that will be stored for further analysis. In the ATLAS experiment at the Large Hadron Collider (LHC) two different architectures for accommodating a level-1 track trigger are being investigated. The tracker has more readout channels than can be readout in time for the trigger decision. Both architectures aim for a data reduction of 10-100 in order to make readout of data possible in time for a level-1 trigger decision. In the first architecture the data reduction is achieved by reading out only parts of the detector seeded by a high rate pre-trigger ...

Metformin inhibits TGF-β1-induced epithelial-to-mesenchymal transition-like process and stem-like properties in GBM via AKT/mTOR/ZEB1 pathway.

Science.gov (United States)

Song, Yang; Chen, Yong; Li, Yunqian; Lyu, Xiaoyan; Cui, Jiayue; Cheng, Ye; Zhao, Liyan; Zhao, Gang

2018-01-23

Glioblastoma (GBM) is the most frequent and aggressive brain tumor in adults. In spite of advances in diagnosis and therapy, the prognosis is still relatively poor. The invasive property of GBM is the major cause of death in patients. Epithelial-to-mesenchymal transition-like process (EMT-like process) is considered to play an important role in the invasive property. Metformin has been reported as a regulator of EMT-like process. In this study, we confirmed that metformin inhibited TGF-β1-induced EMT-like process and EMT-associated migration and invasion in LN18 and U87 GBM cells. Our results also showed that metformin significantly suppressed self-renewal capacity of glioblastoma stem cells (GSCs), and expression of stem cell markers Bmi1, Sox2 and Musashi1, indicating that metformin can inhibit cancer stem-like properties of GBM cells. We further clarified that metformin specifically inhibited TGF-β1 activated AKT, the downstream molecular mTOR and the leading transcription factor ZEB1. Taken together, our data demonstrate that metformin inhibits TGF-β1-induced EMT-like process and cancer stem-like properties in GBM cells via AKT/mTOR/ZEB1 pathway and provide evidence of metformin for further clinical investigation targeted GBM.

A survival analysis of GBM patients in the West of Scotland pre- and post-introduction of the Stupp regime.

Science.gov (United States)

Teo, Mario; Martin, Sean; Owusu-Agyemang, Kevin; Nowicki, Stefan; Clark, Brian; Mackinnon, Mairi; Stewart, Willie; Paul, James; St George, Jerome

2014-06-01

It is now accepted that the concomitant administration of temozolomide with radiotherapy (Stupp regime), in the treatment of patients with newly diagnosed glioblastoma multiforme (GBM), significantly improves survival and this practice has been adopted locally since 2004. However, survival outcomes in cancer can vary in different population groups, and outcomes can be affected by a number of local factors including socioeconomic status. In the West of Scotland, we have one of the worse socioeconomic status and overall health record for a western European country. With the ongoing reorganisation and rationalisation in the National Health Service, the addition of prolonged courses of chemotherapy to patients' management significantly adds to the financial burden of a cash stripped NHS. A survival analysis in patients with GBM was therefore performed, comparing outcomes of pre- and post-introduction of the Stupp regime, to justify the current practice. Prospectively collected clinical data were analysed in 105 consecutive patients receiving concurrent chemoradiotherapy (Stupp regime) following surgical treatment of GBM between December 2004 and February 2009. This was compared to those of 106 consecutive GBM patients who had radical radiotherapy (pre-Stupp regime) post-surgery between January 2001 and February 2006. The median overall survival for the post-Stupp cohort was 15.3 months (range, 2.83-50.5 months), with 1-year and 2-year overall survival rates of 65.7% and 19%, respectively. This was in comparison with the median overall pre-Stupp survival of 10.7 months, with 1-year and 2-year survival rates of 42.6% and 12%, respectively (log-rank test, p GBM patients in the West of Scotland.

Seroadaptive Strategies of Gay & Bisexual Men (GBM) with the Highest Quartile Number of Sexual Partners in Vancouver, Canada.

Science.gov (United States)

Card, Kiffer G; Lachowsky, Nathan J; Cui, Zishan; Sereda, Paul; Rich, Ashleigh; Jollimore, Jody; Howard, Terry; Birch, Robert; Carter, Allison; Montaner, Julio; Moore, David; Hogg, Robert S; Roth, Eric Abella

2017-05-01

Despite continued research among men with more sexual partners, little information exists on their seroadaptive behavior. Therefore, we examined seroadaptive anal sex strategies among 719 Vancouver gay and bisexual men (GBM) recruited using respondent-driven sampling. We provide descriptive, bivariable, and multivariable adjusted statistics, stratified by HIV status, for the covariates of having ≥7 male anal sex partners in the past 6 months (Population fourth quartile versus <7). Sensitivity Analysis were also performed to assess the robustness of this cut-off. Results suggest that GBM with more sexual partners are more likely to employ seroadaptive strategies than men with fewer partners. These strategies may be used in hopes of offsetting risk, assessing needs for subsequent HIV testing, and balancing personal health with sexual intimacy. Further research is needed to determine the efficacy of these strategies, assess how GBM perceive their efficacy, and understand the social and health impacts of their widespread uptake.

Performance of CaSO4:Dy detectors

International Nuclear Information System (INIS)

Setti, M.C.; Silva, G.R.; Pela, C.A.; Bruco, J.L.; Borges, J.C.

2004-01-01

CaSO 4 :Dy detectors have been used in personal dosimetry. The MRA company recently entered into the market of these detectors. Searching to assure a product quality level that would satisfy its customs most expectancies, MRA programmed several tests to qualify and quantify these detectors main characteristics, before their definitive insertion in the market. Preliminary tests furnished a value of 29,5 ± 1,2 nC for homogeneity and a maximum dispersion of 3 % for linearity . (author)

The high-level neutron coincidence counter (HLNCC) family of detectors

International Nuclear Information System (INIS)

Ramalho, A.; Dahn, E.; Selleck, E.; Kupryashkin, V.; Dubreuil, A.

1983-01-01

A description of a group of detectors based on The High-Level Neutron Coincidence Counter (HLNCC) concept is presented. Experience in their utilization is summarized and the procedures followed in calibration and data treatment are described. Advantages of the use of this variety of detectors in simplifying the NDA verifications, reducing the interference with facility operators, and increasing the effectiveness of the inspectors' work are stressed. Likewise, remaining problems such as the need for a vigorous programme directed at achieving the best independent calibrations are emphasized. (author)

Discontinuation of Hemodialysis in a Patient with Anti-GBM Disease by the Treatment with Corticosteroids and Plasmapheresis despite Several Predictors for Dialysis-Dependence

Directory of Open Access Journals (Sweden)

Yoshihide Fujigaki

2017-01-01

Full Text Available A 26-year-old man highly suspected of having antiglomerular basement membrane (GBM disease was treated with corticosteroid pulse therapy 9 days after initial infection-like symptoms with high procalcitonin value. The patient required hemodialysis the next day of the treatment due to oliguria. In addition to corticosteroid therapy, plasmapheresis was introduced and the patient could discontinue hemodialysis 43 days after the treatment. Kidney biopsy after initiation of hemodialysis confirmed anti-GBM disease with 86.3% crescent formation. Physician should keep in mind that active anti-GBM disease shows even high procalcitonin value in the absence of infection. To pursue recovery of renal function, the challenge of the immediate and persistent treatment with high-dose corticosteroids plus plasmapheresis for highly suspected anti-GBM disease is vitally important despite the presence of reported predictors for dialysis-dependence including oliguria and requiring hemodialysis at presentation.

An Ordinary Short Gamma-Ray Burst with Extraordinary Implications: Fermi -GBM Detection of GRB 170817A

Energy Technology Data Exchange (ETDEWEB)

Goldstein, A.; Roberts, O. J.; Connaughton, V. [Science and Technology Institute, Universities Space Research Association, Huntsville, AL 35805 (United States); Veres, P.; Briggs, M. S.; Hamburg, R.; Preece, R. D.; Poolakkil, S. [Center for Space Plasma and Aeronomic Research, University of Alabama in Huntsville, 320 Sparkman Drive, Huntsville, AL 35899 (United States); Burns, E.; Racusin, J.; Canton, T. Dal [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Kocevski, D.; Wilson-Hodge, C. A.; Hui, C. M.; Littenberg, T. [Astrophysics Office, ST12, NASA/Marshall Space Flight Center, Huntsville, AL 35812 (United States); Kienlin, A. von [Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching (Germany); Christensen, N.; Broida, J. [Physics and Astronomy, Carleton College, MN 55057 (United States); Siellez, K. [Center for Relativistic Astrophysics and School of Physics, Georgia Institute of Technology, Atlanta, GA 30332 (United States); Blackburn, L., E-mail: Adam.M.Goldstein@nasa.gov [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); and others

2017-10-20

On 2017 August 17 at 12:41:06 UTC the Fermi Gamma-ray Burst Monitor (GBM) detected and triggered on the short gamma-ray burst (GRB) 170817A. Approximately 1.7 s prior to this GRB, the Laser Interferometer Gravitational-wave Observatory triggered on a binary compact merger candidate associated with the GRB. This is the first unambiguous coincident observation of gravitational waves and electromagnetic radiation from a single astrophysical source and marks the start of gravitational-wave multi-messenger astronomy. We report the GBM observations and analysis of this ordinary short GRB, which extraordinarily confirms that at least some short GRBs are produced by binary compact mergers.

Temozolomide, sirolimus and chloroquine is a new therapeutic combination that synergizes to disrupt lysosomal function and cholesterol homeostasis in GBM cells.

Science.gov (United States)

Hsu, Sanford P C; Kuo, John S; Chiang, Hsin-Chien; Wang, Hsin-Ell; Wang, Yu-Shan; Huang, Cheng-Chung; Huang, Yi-Chun; Chi, Mau-Shin; Mehta, Minesh P; Chi, Kwan-Hwa

2018-01-23

Glioblastoma (GBM) cells are characterized by high phagocytosis, lipogenesis, exocytosis activities, low autophagy capacity and high lysosomal demand are necessary for survival and invasion. The lysosome stands at the cross roads of lipid biosynthesis, transporting, sorting between exogenous and endogenous cholesterol. We hypothesized that three already approved drugs, the autophagy inducer, sirolimus (rapamycin, Rapa), the autophagy inhibitor, chloroquine (CQ), and DNA alkylating chemotherapy, temozolomide (TMZ) could synergize against GBM. This repurposed triple therapy combination induced GBM apoptosis in vitro and inhibited GBM xenograft growth in vivo . Cytotoxicity is caused by induction of lysosomal membrane permeabilization and release of hydrolases, and may be rescued by cholesterol supplementation. Triple treatment inhibits lysosomal function, prevents cholesterol extraction from low density lipoprotein (LDL), and causes clumping of lysosome associated membrane protein-1 (LAMP-1) and lipid droplets (LD) accumulation. Co-treatment of the cell lines with inhibitor of caspases and cathepsin B only partially reverse of cytotoxicities, while N-acetyl cysteine (NAC) can be more effective. A combination of reactive oxygen species (ROS) generation from cholesterol depletion are the early event of underling mechanism. Cholesterol repletion abolished the ROS production and reversed the cytotoxicity from QRT treatment. The shortage of free cholesterol destabilizes lysosomal membranes converting aborted autophagy to apoptosis through either direct mitochondria damage or cathepsin B release. This promising anti-GBM triple therapy combination severely decreases mitochondrial function, induces lysosome-dependent apoptotic cell death, and is now poised for further clinical testing and validation.

Patients double-seropositive for ANCA and anti-GBM antibodies have varied renal survival, frequency of relapse, and outcomes compared to single-seropositive patients.

Science.gov (United States)

McAdoo, Stephen P; Tanna, Anisha; Hrušková, Zdenka; Holm, Lisa; Weiner, Maria; Arulkumaran, Nishkantha; Kang, Amy; Satrapová, Veronika; Levy, Jeremy; Ohlsson, Sophie; Tesar, Vladimir; Segelmark, Mårten; Pusey, Charles D

2017-09-01

Co-presentation with both ANCA and anti-GBM antibodies is thought to be relatively rare. Current studies of such 'double-positive' cases report small numbers and variable outcomes. To study this further we retrospectively analyzed clinical features and long-term outcomes of a large cohort of 568 contemporary patients with ANCA-associated vasculitis, 41 patients with anti-GBM disease, and 37 double-positive patients with ANCA and anti-GBM disease from four European centers. Double-positive patients shared characteristics of ANCA-associated vasculitis (AAV), such as older age distribution and longer symptom duration before diagnosis, and features of anti-GBM disease, such as severe renal disease and high frequency of lung hemorrhage at presentation. Despite having more evidence of chronic injury on renal biopsy compared to patients with anti-GBM disease, double-positive patients had a greater tendency to recover from being dialysis-dependent after treatment and had intermediate long-term renal survival compared to the single-positive patients. However, overall patient survival was similar in all three groups. Predictors of poor patient survival included advanced age, severe renal failure, and lung hemorrhage at presentation. No single-positive anti-GBM patients experienced disease relapse, whereas approximately half of surviving patients with AAV and double-positive patients had recurrent disease during a median follow-up of 4.8 years. Thus, double-positive patients have a truly hybrid disease phenotype, requiring aggressive early treatment for anti-GBM disease, and careful long-term follow-up and consideration for maintenance immunosuppression for AAV. Since double-positivity appears common, further work is required to define the underlying mechanisms of this association and define optimum treatment strategies. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Fermi/GBM Update on the Orbital Ephemeris of Swift J0243.6+6124

Science.gov (United States)

Jenke, P.; Wilson-Hodge, C. A.; Malacaria, C.

2018-02-01

Using Fermi/GBM data between MJD 58098 and 58154 (2017 December 11 to 2018 February 5) in the 12-50 keV range, we determine a new orbital ephemeris for the newly discovered (ATEL #10809) Be X-ray binary Swift J0243.6+6124.

SU-F-R-17: Advancing Glioblastoma Multiforme (GBM) Recurrence Detection with MRI Image Texture Feature Extraction and Machine Learning

Energy Technology Data Exchange (ETDEWEB)

Yu, V; Ruan, D; Nguyen, D; Kaprealian, T; Chin, R; Sheng, K [UCLA School of Medicine, Los Angeles, CA (United States)

2016-06-15

Purpose: To test the potential of early Glioblastoma Multiforme (GBM) recurrence detection utilizing image texture pattern analysis in serial MR images post primary treatment intervention. Methods: MR image-sets of six time points prior to the confirmed recurrence diagnosis of a GBM patient were included in this study, with each time point containing T1 pre-contrast, T1 post-contrast, T2-Flair, and T2-TSE images. Eight Gray-level co-occurrence matrix (GLCM) texture features including Contrast, Correlation, Dissimilarity, Energy, Entropy, Homogeneity, Sum-Average, and Variance were calculated from all images, resulting in a total of 32 features at each time point. A confirmed recurrent volume was contoured, along with an adjacent non-recurrent region-of-interest (ROI) and both volumes were propagated to all prior time points via deformable image registration. A support vector machine (SVM) with radial-basis-function kernels was trained on the latest time point prior to the confirmed recurrence to construct a model for recurrence classification. The SVM model was then applied to all prior time points and the volumes classified as recurrence were obtained. Results: An increase in classified volume was observed over time as expected. The size of classified recurrence maintained at a stable level of approximately 0.1 cm{sup 3} up to 272 days prior to confirmation. Noticeable volume increase to 0.44 cm{sup 3} was demonstrated at 96 days prior, followed by significant increase to 1.57 cm{sup 3} at 42 days prior. Visualization of the classified volume shows the merging of recurrence-susceptible region as the volume change became noticeable. Conclusion: Image texture pattern analysis in serial MR images appears to be sensitive to detecting the recurrent GBM a long time before the recurrence is confirmed by a radiologist. The early detection may improve the efficacy of targeted intervention including radiosurgery. More patient cases will be included to create a generalizable

PixTrig: a Level 2 track finding algorithm based on pixel detector

CERN Document Server

Baratella, A; Morettini, P; Parodi, F

2000-01-01

This note describes an algorithm for track search at Level 2 based on pixel detector. Using three pixel clusters we can produce a reconstruction of the track parameter in both z and R-phi plane. These track segments can be used as seed for more sophisticated track finding algorithms or used directly, especially when impact parameter resolution is crucial. The algorithm efficiency is close to 90% for pt > 1 GeV/c and the processing time is small enough to allow a complete detector reconstruction (non RoI guided) within the Level 2 processing.

A neutron activation detector

International Nuclear Information System (INIS)

Ambardanishvili, T.S.; Kolomiitsev, M.A.; Zakharina, T.Y.; Dundua, V.J.; Chikhladze, N.V.

1973-01-01

The present invention concerns a neutron activation detector made from a moulded and hardened composition. According to the invention, that composition contains an activable substance constituted by at least two chemical elements and/or compounds of at least two chemical elements. Each of these chemical elements is capable of reacting with the neutrons forming radio-active isotopes with vatious levels of energy during desintegration. This neutron detector is mainly suitable for measuring integral thermal neutron and fast neutron fluxes during irradiation of the sample, and also for measuring the intensities of neutron fields [fr

Circulating gamma delta T cells are activated and depleted during progression of high-grade gliomas: Implications for gamma delta T cell therapy of GBM

Science.gov (United States)

Glioblastoma multiforme (GBM) remains frustratingly impervious to any existing therapy. We have previously shown that GBM is sensitive to recognition and lysis by ex vivo activated gamma delta T cells, a minor subset of lymphocytes that innately recognize autologous stress-associated target antigens...

Routinely used immunoassays do not detect circulating anti-GBM antibodies against native NC1 hexamer and EA epitope of the α3 chain of type IV collagen.

Science.gov (United States)

Clavarino, Giovanna; Gauthier, Arnaud; Hellmark, Thomas; Carron, Pierre-Louis; Giovannini, Diane; Colliard, Sophie; Dragon-Durey, Marie-Agnès; Segelmark, Mårten; Cesbron, Jean-Yves; Dumestre-Pérard, Chantal

2018-04-12

Detection of circulating anti-GBM antibodies has a key role for the diagnosis of Goodpasture syndrome but immunoassays using purified or recombinant alpha3(IV)NC1 as antigen do not recognize all anti-GBM antibodies. We show that anti-GBM antibodies directed against epitopes in their native conformation or cryptic epitopes are detected by indirect immunofluorescence. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A Chimeric Antibody against ACKR3/CXCR7 in Combination with TMZ Activates Immune Responses and Extends Survival in Mouse GBM Models.

Science.gov (United States)

Salazar, Nicole; Carlson, Jeffrey C; Huang, Kexin; Zheng, Yayue; Oderup, Cecilia; Gross, Julia; Jang, Andrew D; Burke, Thomas M; Lewén, Susanna; Scholz, Alexander; Huang, Serina; Nease, Leona; Kosek, Jon; Mittelbronn, Michel; Butcher, Eugene C; Tu, Hua; Zabel, Brian A

2018-05-02

Glioblastoma (GBM) is the least treatable type of brain tumor, afflicting over 15,000 people per year in the United States. Patients have a median survival of 16 months, and over 95% die within 5 years. The chemokine receptor ACKR3 is selectively expressed on both GBM cells and tumor-associated blood vessels. High tumor expression of ACKR3 correlates with poor prognosis and potential treatment resistance, making it an attractive therapeutic target. We engineered a single chain FV-human FC-immunoglobulin G1 (IgG 1 ) antibody, X7Ab, to target ACKR3 in human and mouse GBM cells. We used hydrodynamic gene transfer to overexpress the antibody, with efficacy in vivo. X7Ab kills GBM tumor cells and ACKR3-expressing vascular endothelial cells by engaging the cytotoxic activity of natural killer (NK) cells and complement and the phagocytic activity of macrophages. Combining X7Ab with TMZ allows the TMZ dosage to be lowered, without compromising therapeutic efficacy. Mice treated with X7Ab and in combination with TMZ showed significant tumor reduction by MRI and longer survival overall. Brain-tumor-infiltrating leukocyte analysis revealed that X7Ab enhances the activation of M1 macrophages to support anti-tumor immune response in vivo. Targeting ACKR3 with immunotherapeutic monoclonal antibodies (mAbs) in combination with standard of care therapies may prove effective in treating GBM. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

On the Interpretation of the Fermi-GBM Transient Observed in Coincidence with LIGO Gravitational-wave Event GW150914

Science.gov (United States)

Connaughton, V.; Burns, E.; Goldstein, A.; Blackburn, L.; Briggs, M. S.; Christensen, N.; Hui, C. M.; Kocevski, D.; Littenberg, T.; McEnery, J. E.; Racusin, J.; Shawhan, P.; Veitch, J.; Wilson-Hodge, C. A.; Bhat, P. N.; Bissaldi, E.; Cleveland, W.; Giles, M. M.; Gibby, M. H.; von Kienlin, A.; Kippen, R. M.; McBreen, S.; Meegan, C. A.; Paciesas, W. S.; Preece, R. D.; Roberts, O. J.; Stanbro, M.; Veres, P.

2018-01-01

The weak transient detected by the Fermi Gamma-ray Burst Monitor (GBM) 0.4 s after GW150914 has generated much speculation regarding its possible association with the black hole binary merger. Investigation of the GBM data by Connaughton et al. revealed a source location consistent with GW150914 and a spectrum consistent with a weak, short gamma-ray burst. Greiner et al. present an alternative technique for fitting background-limited data in the low-count regime, and call into question the spectral analysis and the significance of the detection of GW150914-GBM presented in Connaughton et al. The spectral analysis of Connaughton et al. is not subject to the limitations of the low-count regime noted by Greiner et al. We find Greiner et al. used an inconsistent source position and did not follow the steps taken in Connaughton et al. to mitigate the statistical shortcomings of their software when analyzing this weak event. We use the approach of Greiner et al. to verify that our original spectral analysis is not biased. The detection significance of GW150914-GBM is established empirically, with a false-alarm rate (FAR) of ∼ {10}-4 Hz. A post-trials false-alarm probability (FAP) of 2.2× {10}-3 (2.9σ ) of this transient being associated with GW150914 is based on the proximity in time to the gravitational-wave event of a transient with that FAR. The FAR and the FAP are unaffected by the spectral analysis that is the focus of Greiner et al.

FERMI GBM OBSERVATIONS OF V404 CYG DURING ITS 2015 OUTBURST

Energy Technology Data Exchange (ETDEWEB)

Jenke, P. A.; Veres, P.; Briggs, M. S.; Burns, E. [University of Alabama in Huntsville, Huntsville, AL 35805 (United States); Wilson-Hodge, C. A.; Hui, M. [Marshall Space Flight Center, Huntsville, AL 35812 (United States); Homan, Jeroen [MIT Kavli Institute for Astrophysics and Space Research, 77 Massachusetts Avenue 37-582D, Cambridge, MA 02139 (United States); Connaughton, V.; Finger, M. H., E-mail: peter.a.jenke@nasa.gov [Universities Space Research Association, Huntsville, AL 35805 (United States)

2016-07-20

V404 Cygni was discovered in 1989 by the Ginga X-ray satellite during its only previously observed X-ray outburst and soon after confirmed as a black hole binary. On 2015 June 15, the Gamma-ray Burst Monitor (GBM) triggered on a new outburst of V404 Cygni. We present 13 days of GBM observations of this outburst, including Earth occultation flux measurements and spectral and temporal analysis. The Earth occultation fluxes reached 30 Crab with detected emission to 100 keV and determined, via hardness ratios, that the source was in a hard state. At high luminosity, spectral analysis between 8 and 300 keV showed that the electron temperature decreased with increasing luminosity. This is expected if the protons and electrons are in thermal equilibrium during an outburst with the electrons cooled by the Compton scattering of softer seed photons from the disk. However, the implied seed photon temperatures are unusually high, suggesting a contribution from another source, such as the jet. No evidence of state transitions is seen during this time period. The temporal analysis reveals power spectra that can be modeled with two or three strong, broad Lorentzians, similar to the power spectra of black hole binaries in their hard state.

Combinatorial Drug Testing in 3D Microtumors Derived from GBM Patient-Derived Xenografts Reveals Cytotoxic Synergy in Pharmacokinomics-informed Pathway Interactions.

Science.gov (United States)

Gilbert, Ashley N; Anderson, Joshua C; Duarte, Christine W; Shevin, Rachael S; Langford, Catherine P; Singh, Raj; Gillespie, G Yancey; Willey, Christopher D

2018-05-30

Glioblastoma multiforme (GBM), the most common form of primary malignant brain cancer in adults, is a devastating disease for which effective treatment has remained elusive for over 75 years. One reason for the minimal progress during this time is the lack of accurate preclinical models to represent the patient's tumor's in vivo environment, causing a disconnect in drug therapy effectiveness between the laboratory and clinic. While patient-derived xenografts (PDX's or xenolines) are excellent human tumor representations, they are not amenable to high throughput testing. Therefore, we developed a miniaturized xenoline system (microtumors) for drug testing. Nineteen GBM xenolines were profiled for global kinase (kinomic) activity revealing actionable kinase targets associated with intracranial tumor growth rate. Kinase inhibitors for these targets (WP1066, selumetinib, crizotinib, and cediranib) were selected for single and combination therapy using a fully human-derived three-dimensional (3D) microtumor model of GBM xenoline cells embedded in HuBiogel for subsequent molecular and phenotype assays. GBM microtumors closely resembled orthotopically-implanted tumors based on immunohistochemical analysis and displayed kinomic and morphological diversity. Drug response testing could be reproducibly performed in a 96-well format identifying several synergistic combinations. Our findings indicate that 3D microtumors can provide a suitable high-throughput model for combination drug testing.

Pixel detector readout electronics with two-level discriminator scheme

International Nuclear Information System (INIS)

Pengg, F.

1998-01-01

In preparation for a silicon pixel detector with more than 3,000 readout channels per chip for operation at the future large hadron collider (LHC) at CERN the analog front end of the readout electronics has been designed and measured on several test-arrays with 16 by 4 cells. They are implemented in the HP 0.8 microm process but compatible with the design rules of the radiation hard Honeywell 0.8 microm bulk process. Each cell contains bump bonding pad, preamplifier, discriminator and control logic for masking and testing within a layout area of only 50 microm by 140 microm. A new two-level discriminator scheme has been implemented to cope with the problems of time-walk and interpixel cross-coupling. The measured gain of the preamplifier is 900 mV for a minimum ionizing particle (MIP, about 24,000 e - for a 300 microm thick Si-detector) with a return to baseline within 750 ns for a 1 MIP input signal. The full readout chain (without detector) shows an equivalent noise charge to 60e - r.m.s. The time-walk, a function of the separation between the two threshold levels, is measured to be 22 ns at a separation of 1,500 e - , which is adequate for the 40 MHz beam-crossing frequency at the LHC. The interpixel cross-coupling, measured with a 40fF coupling capacitance, is less than 3%. A single cell consumes 35 microW at 3.5 V supply voltage

Experimental anti-GBM nephritis as an analytical tool for studying spontaneous lupus nephritis.

Science.gov (United States)

Du, Yong; Fu, Yuyang; Mohan, Chandra

2008-01-01

Systemic lupus erythematosus (SLE) is an autoimmune disease that results in immune-mediated damage to multiple organs. Among these, kidney involvement is the most common and fatal. Spontaneous lupus nephritis (SLN) in mouse models has provided valuable insights into the underlying mechanisms of human lupus nephritis. However, SLN in mouse models takes 6-12 months to manifest; hence there is clearly the need for a mouse model that can be used to unveil the pathogenic processes that lead to immune nephritis over a shorter time frame. In this article more than 25 different molecules are reviewed that have been studied both in the anti-glomerular basement membrane (anti-GBM) model and in SLN and it was found that these molecules influence both diseases in a parallel fashion, suggesting that the two disease settings share common molecular mechanisms. Based on these observations, the authors believe the experimental anti-GBM disease model might be one of the best tools currently available for uncovering the downstream molecular mechanisms leading to SLN.

COMMISSIONING AND DETECTOR PERFORMANCE GROUPS

CERN Multimedia

D. Acosta

The commissioning effort is presently addressing two main areas: the commissioning of the hardware components at the pit and the coordination of the activities of the newly constituted Detector Performance groups (DPGs). At point 5, a plan regarding the service cavern and the commissioning of the connections of the off-detector electronics (for the data collection line and trigger primitive generation) to the central DAQ and the central Trigger has been defined. This activity was started early February and will continue until May. It began with Tracker electronics followed so far by HCAL and CSC. The goal is to have by May every detector commission, as much as possible, their data transfer paths from FED to Central DAQ as well as their trigger setups between TPGs and Global Level 1 trigger. The next focus is on connections of front-ends to the service cavern. This depends strongly on the installations of services. Presently the only detector which has its link fibers connected to the off-detector electr...

Instrument Response Modeling and Simulation for the GLAST Burst Monitor

International Nuclear Information System (INIS)

Kippen, R. M.; Hoover, A. S.; Wallace, M. S.; Pendleton, G. N.; Meegan, C. A.; Fishman, G. J.; Wilson-Hodge, C. A.; Kouveliotou, C.; Lichti, G. G.; Kienlin, A. von; Steinle, H.; Diehl, R.; Greiner, J.; Preece, R. D.; Connaughton, V.; Briggs, M. S.; Paciesas, W. S.; Bhat, P. N.

2007-01-01

The GLAST Burst Monitor (GBM) is designed to provide wide field of view observations of gamma-ray bursts and other fast transient sources in the energy range 10 keV to 30 MeV. The GBM is composed of several unshielded and uncollimated scintillation detectors (twelve NaI and two BGO) that are widely dispersed about the GLAST spacecraft. As a result, reconstructing source locations, energy spectra, and temporal properties from GBM data requires detailed knowledge of the detectors' response to both direct radiation as well as that scattered from the spacecraft and Earth's atmosphere. This full GBM instrument response will be captured in the form of a response function database that is derived from computer modeling and simulation. The simulation system is based on the GEANT4 Monte Carlo radiation transport simulation toolset, and is being extensively validated against calibrated experimental GBM data. We discuss the architecture of the GBM simulation and modeling system and describe how its products will be used for analysis of observed GBM data. Companion papers describe the status of validating the system

DISTRIBUTION OF GBM HEPARAN-SULFATE PROTEOGLYCAN CORE PROTEIN AND SIDE-CHAINS IN HUMAN GLOMERULAR-DISEASES

NARCIS (Netherlands)

VANDENBORN, J; VANDENHEUVEL, LPWJ; BAKKER, MAH; VEERKAMP, JH; ASSMANN, KJM; WEENING, JJ; BERDEN, JHM

Using monoclonal antibodies (mAbs) recognizing either the core protein or the heparan sulfate (HS) side chain of human GBM heparan sulfate proteoglycan (HSPG), we investigated their glomerular distribution on cryostat sections of human kidney tissues. The study involved 95 biopsies comprising twelve

Tight regulation between cell survival and programmed cell death in GBM stem-like cells by EGFR/GSK3b/PP2A signaling.

Science.gov (United States)

Gürsel, Demirkan B; Banu, Matei A; Berry, Nicholas; Marongiu, Roberta; Burkhardt, Jan-Karl; Kobylarz, Keith; Kaplitt, Michael G; Rafii, Shahin; Boockvar, John A

2015-01-01

Malignant gliomas represent one of the most aggressive forms of cancer, displaying high mortality rates and limited treatment options. Specific subpopulations of cells residing in the tumor niche with stem-like characteristics have been postulated to initiate and maintain neoplasticity while resisting conventional therapies. The study presented here aims to define the role of glycogen synthase kinase 3 beta (GSK3b) in patient-derived glioblastoma (GBM) stem-like cell (GSC) proliferation, apoptosis and invasion. To evaluate the potential role of GSK3b in GBM, protein profiles from 68 GBM patients and 20 normal brain samples were analyzed for EGFR-mediated PI3kinase/Akt and GSK3b signaling molecules including protein phosphatase 2A (PP2A). To better understand the function of GSK3b in GBM, GSCs were isolated from GBM patient samples. Blocking GSK3b phosphorylation at Serine 9 attenuated cell proliferation while concomitantly stimulating apoptosis through activation of Caspase-3 in patient-derived GSCs. Increasing GSK3b protein content resulted in the inhibition of cell proliferation, colony formation and stimulated programmed cell death. Depleting GSK3b in GSCs down regulated PP2A. Furthermore, knocking down PP2A or blocking its activity by okadaic acid inactivated GSK3b by increasing GSK3b phosphorylation at Serine 9. Our data suggests that GSK3b may function as a regulator of apoptosis and tumorigenesis in GSCs. Therapeutic approaches targeting GSK3b in glioblastoma stem-like cells may be a useful addition to our current therapeutic armamentarium.

Synthesis of Axial Power Distribution Using 5-Level Ex-core Detector in a Core Protection System

International Nuclear Information System (INIS)

Koo, Bon-Seung; Lee, Chung-Chan; Zee, Sung-Quun

2007-01-01

In ABB-CE digital plants, Core Protection Calculator System (CPCS) is used for a core protection based on several online measured system parameters including 3- level safety grade ex-core detector signals. The CPCS provides four independent channels for the departure from a nucleate boiling ratio (DNBR) and local power density (LPD) trip signals to the reactor protection system. Each channel consists of a core protection calculator (CPC) and a control element assembly calculator (CEAC). The cubic spline synthesis technique has been used in online calculations of the core axial power distributions using 3-level ex-core detector signals in CPC. The pre-determined cubic spline function sets are used depending on the characteristics of the ex-core detector responses. But this method shows large power distribution errors for the extremely skewed axial shapes due to restrictive function sets and an incorrect SAM value. Especially thus situation is worse at a higher burnup. To solve these problems, the cubic spline function sets are improved and it is demonstrated that the axial power shapes can be synthesized more accurately with the new function sets than those of a conventional CPC. In this paper, synthesis of an axial power distribution using a 5-level ex-core detector is described and the axial power distributions are compared between 3-level and 5-level ex-core detector systems

An experimental investigation of an air cooling scheme for removing environmentally imposed heat loads from the multiplicity and vertex detector's main enclosure

International Nuclear Information System (INIS)

Cunningham, R.; Bernardin, J.D.; Simon-Gillo, J.

1997-11-01

This report presents a summary of an experimental investigation of a closed loop air cooling system designed to control the temperature and humidity in the main enclosure of the multiplicity and vertex detector (MVD). Measurements of the cooling air flow rate, the humidity levels inside and outside of the MVD, and the cooling air temperatures were used to assess the performance of the system and to characterize the system limitations and potential assembly problems. The results of the study indicate that several design changes are needed in the final design to meet the temperature and humidity operating requirements. A thorough set of design change recommendations that satisfy these operating criteria completes this report

Gas filled detectors

International Nuclear Information System (INIS)

Stephan, C.

1993-01-01

The main types of gas filled nuclear detectors: ionization chambers, proportional counters, parallel-plate avalanche counters (PPAC) and microstrip detectors are described. New devices are shown. A description of the processes involved in such detectors is also given. (K.A.) 123 refs.; 25 figs.; 3 tabs

Axial shape index calculation for the 3-level excore detector

Energy Technology Data Exchange (ETDEWEB)

Kim, Han Gon; Kim, Yong Hee; Kim, Byung Sop; Lee, Sang Hee; Cho, Sung Jae [Korea Electric Power Research Institute, Taejon (Korea, Republic of)

1998-12-31

A new method based on the alternating conditional expectation (ACE) algorithm is developed to calculate axial shape index (ASI) for the 3-level excore detector. The ACE algorithm, a type of nonparametric regression algorithms, yields an optimal relationship between a dependent variable and multiple independent variables. In this study, the simple correlation between ASI and excore detector signals is developed using the Younggwang nuclear power plant unit 3 (YGN-3) data without any preprocessing on the relationships between independent variables and dependent variable. The numerical results show that simple correlations exist between the three excore signals and ASI of the core. The accuracy of the new method is much better than those of the current CPC and COLSS algorithms. 5 refs., 2 figs., 2 tabs. (Author)

Axial shape index calculation for the 3-level excore detector

Energy Technology Data Exchange (ETDEWEB)

Kim, Han Gon; Kim, Yong Hee; Kim, Byung Sop; Lee, Sang Hee; Cho, Sung Jae [Korea Electric Power Research Institute, Taejon (Korea, Republic of)

1997-12-31

A new method based on the alternating conditional expectation (ACE) algorithm is developed to calculate axial shape index (ASI) for the 3-level excore detector. The ACE algorithm, a type of nonparametric regression algorithms, yields an optimal relationship between a dependent variable and multiple independent variables. In this study, the simple correlation between ASI and excore detector signals is developed using the Younggwang nuclear power plant unit 3 (YGN-3) data without any preprocessing on the relationships between independent variables and dependent variable. The numerical results show that simple correlations exist between the three excore signals and ASI of the core. The accuracy of the new method is much better than those of the current CPC and COLSS algorithms. 5 refs., 2 figs., 2 tabs. (Author)

MODELING THE AFTERGLOW OF THE POSSIBLE FERMI -GBM EVENT ASSOCIATED WITH GW150914

International Nuclear Information System (INIS)

Morsony, Brian J.; Workman, Jared C.; Ryan, Dominic M.

2016-01-01

We model the possible afterglow of the Fermi Gamma-ray Burst Monitor (GBM) event associated with LIGO detection GW150914, under the assumption that the gamma-rays are produced by a short GRB-like relativistic outflow. We model GW150914-GBM as both a weak, on-axis short GRB and normal short GRB seen far off-axis. Given the large uncertainty in the position of GW150914, we determine that the best chance of finding the afterglow is with ASKAP or possibly the Murchinson Widefield Array (MWA), with the flux from an off-axis short GRB reaching 0.2–4 mJy (0.12–16 mJy) at 150 MHz (863.5 MHz) by 1–12 months after the initial event. At low frequencies, the source would evolve from a hard to soft spectrum over several months. The radio afterglow would be detectable for several months to years after it peaks, meaning the afterglow may still be detectable and increasing in brightness NOW (2016 mid-July). With a localization from the MWA or ASKAP, the afterglow would be detectable at higher radio frequencies with the ATCA and in X-rays with Chandra or XMM .

MODELING THE AFTERGLOW OF THE POSSIBLE FERMI -GBM EVENT ASSOCIATED WITH GW150914

Energy Technology Data Exchange (ETDEWEB)

Morsony, Brian J. [Department of Astronomy, University of Maryland, 1113 Physical Sciences Complex, College Park, MD 20742-2421 (United States); Workman, Jared C. [Department of Physical and Environmental Sciences, Colorado Mesa University, Grand Junction, CO 81501 (United States); Ryan, Dominic M., E-mail: morsony@astro.umd.edu [Department of Astronomy, University of California, Berkeley, 501 Campbell Hall #3411, Berkeley, CA 94720-3411 (United States)

2016-07-10

We model the possible afterglow of the Fermi Gamma-ray Burst Monitor (GBM) event associated with LIGO detection GW150914, under the assumption that the gamma-rays are produced by a short GRB-like relativistic outflow. We model GW150914-GBM as both a weak, on-axis short GRB and normal short GRB seen far off-axis. Given the large uncertainty in the position of GW150914, we determine that the best chance of finding the afterglow is with ASKAP or possibly the Murchinson Widefield Array (MWA), with the flux from an off-axis short GRB reaching 0.2–4 mJy (0.12–16 mJy) at 150 MHz (863.5 MHz) by 1–12 months after the initial event. At low frequencies, the source would evolve from a hard to soft spectrum over several months. The radio afterglow would be detectable for several months to years after it peaks, meaning the afterglow may still be detectable and increasing in brightness NOW (2016 mid-July). With a localization from the MWA or ASKAP, the afterglow would be detectable at higher radio frequencies with the ATCA and in X-rays with Chandra or XMM .

Background level of natural radioactivities in a giant water Cherenkov detector and its surrounding environment

International Nuclear Information System (INIS)

Yamamoto, Masayoshi; Sakanoue, Masanobu; Komura, Kazuhisa; Ueno, Kaoru

1989-01-01

The KAMIOKANDE-II water Cherenkov detector for the measurement of nucleon decay and/or solar neutrino has been operating in the underground laboratory at a depth of 2,700 m.w.e. (meter water equivalent) in Kamioka mine of Gifu Prefecture. Concentrations of 238 U, 232 Th, 226 Ra and 222 Rn as the major background sources have been measured for various kinds of rocks, mine water, mine air and high purity water used as a detector during the period from August 1986 to December 1987. The concentration levels of these radionuclides and their seasonal variation have become clear. Some of these results have provided useful informations for decreasing the background level of water Cherenkov detector. (author)

Maine State Briefing Book on low-level radioactive waste management

Energy Technology Data Exchange (ETDEWEB)

1981-08-01

The Maine State Briefing Book is one of a series of state briefing books on low-level radioactive waste management practices. It has been prepared to assist state and Federal agency officials in planning for safe low-level radioactive waste disposal. The report contains a profile of low-level radioactive waste generators in Maine. The profile is the result of a survey of radioactive material licensees in Maine. The briefing book also contains a comprehensive assessment of low-level radioactive waste management issues and concerns as defined by all major interested partices including industry, government, the media, and interest groups. The assessment was developed through personal communications with representatives of interested parties, and through a review of media sources. Lastly, the briefing book provides demographic and socioeconomic data and a discussion of relevant goverment agencies and activities, all of which may impact management practices in Maine.

TLR9 expression in glioma tissues correlated to glioma progression and the prognosis of GBM patients

International Nuclear Information System (INIS)

Wang, Chao; Cao, Shouqiang; Yan, Ying; Ying, Qiao; Jiang, Tao; Xu, Ke; Wu, Anhua

2010-01-01

Our study aims to evaluate the expression of TLR9 in glioma tissues, examine the association between TLR9 expression, clinicopathological variables, and glioma patient outcome, we further characterized the direct effects of TLR9 agonist CpG ODN upon the proliferation and invasion of glioma cells in vitro. RT-PCR and immunofluorescence were used to determine the expression of TLR9 in glioma cell lines and clinical glioma samples. Tissue microarry and immunohistochemistry were applied to evaluated TLR9 expression in 292 newly diagnosed glioma and 13 non-neoplastic brain tissues. We further investigated the effect of CpG ODN on the proliferation and invasion of glioma cells in vitro with MTT assays and matrigel transwell assay respectively. RT-PCR showed that TLR9 expressed in all the glioma samples and glioma cell lines we examined. The tissue array analysis indicated that TLR9 expression is correlated with malignancy of glioma (p < 0.01). Multivariate Cox regression analysis revealed that TLR9 expression is an independent prognostic factor for PFS of GBM patients(P = 0.026). TLR9 agonist CpG ODN has no significant effect on glioma proliferation, but matrigel transwell analysis showed that TLR9 agonist CpG ODN can significantly enhance glioma invasion in vitro. Our data indicated that TLR9 expression increases according to the histopathological grade of glioma, and the TLR9 expression level is related to the PFS of GBM patients. In addition, our findings warrant caution in the directly injection of TLR9 agonist CpG ODN into glioma tissues for the glioma immunotherapy

The role of Gliadel wafers in the treatment of newly diagnosed GBM: a meta-analysis

Directory of Open Access Journals (Sweden)

Xing WK

2015-06-01

Full Text Available Wei-kang Xing,1 Chuan Shao,2 Zhen-yu Qi,1 Chao Yang,1 Zhong Wang1 1Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, 2Department of Neurosurgery, The Second Clinical Medical College of North Sichuan Medical College, Nanchong, Sichuan, People’s Republic of China Background: Standard treatment for high-grade glioma (HGG includes surgery followed by radiotherapy and/or chemotherapy. Insertion of carmustine wafers into the resection cavity as a treatment for malignant glioma is currently a controversial topic among neurosurgeons. Our meta-analysis focused on whether carmustine wafer treatment could significantly benefit the survival of patients with newly diagnosed glioblastoma multiforme (GBM.Method: We searched the PubMed and Web of Science databases without any restrictions on language using the keywords “Gliadel wafers”, “carmustine wafers”, “BCNU wafers”, or “interstitial chemotherapy” in newly diagnosed GBM for the period from January 1990 to March 2015. Randomized controlled trials (RCTs and cohort studies/clinical trials that compared treatments designed with and without carmustine wafers and which reported overall survival or hazard ratio (HR or survival curves were included in this study. Moreover, the statistical analysis was conducted by the STATA 12.0 software.Results: Six studies including two RCTs and four cohort studies, enrolling a total of 513 patients (223 with and 290 without carmustine wafers, matched the selection criteria. Carmustine wafers showed a strong advantage when pooling all the included studies (HR =0.63, 95% confidence interval (CI =0.49–0.81; P=0.019. However, the two RCTs did not show a statistical increase in survival in the group with carmustine wafer compared to the group without it (HR =0.51, 95% CI =0.18–1.41; P=0.426, while the cohort studies demonstrated a significant survival increase (HR =0.59, 95% CI =0.44–0.79; P<0.0001.Conclusion

Development of intelligent photomultipliers for the JUNO detector

Energy Technology Data Exchange (ETDEWEB)

Lenz, Florian; Meloni, Marta; Soiron, Michael; Stahl, Achim; Steinmann, Jochen; Wiebusch, Christopher [III. Physikalisches Institut B, RWTH Aachen University, 52056 Aachen (Germany)

2016-07-01

The JUNO experiment will be a 20kt liquid scintillator neutrino detector near Kaiping, China, 50km from two nuclear power plants. Its main goal is the determination of the neutrino mass hierarchy from a precise measurement of the energy spectrum of neutrinos. Due to the detector size it is not possible to digitize the signal outside the detector cavern. Therefore FPGAs with a low-level reconstruction combined with a fast ADC mounted on the base will convert the PMTs into intelligent sensors. Advantages and disadvantages of this design are be discussed,and first measurements are shown.

The LDC detector concept

Indian Academy of Sciences (India)

Abstract. In preparation of the experimental program at the international linear collider (ILC), the large detector concept (LDC) is being developed. The main points of the LDC are a large volume gaseous tracking system, combined with high precision vertex detector and an extremely granular calorimeter. The main design ...

Detector for atomic particles and ionizing radiations

International Nuclear Information System (INIS)

Mallet, Georges; Ythier, Christian.

1976-01-01

The aim of this invention is to provide improved detectors of atomic particles and of ionising radiations, having maximum sensitivity, by virtually suppressing all absorption of the radiation scattered by the main detector, so that these detectors are particularly suitable for fitting to anti-Compton spectrometers. Reference is particularly made to detectors of the Ge(Li) type, lithium compensated germanium, which are the most used. It is however made clear that this choice is not restrictive and that this invention not only applies to all known types of detectors and particularly to scintillator detectors, for instance to detectors such as NaI (Tl), composed of a monocrystal of a thallium activated alkaline halogenide, but also to gas, ionisation chamber and luminescent chamber type detectors and in general to all the known devices that convert the energy of particles into electric signals. Owing to the fact that the walls of the enclosure containing the main detector are composed, in the part around this detector, of an auxiliary detector, the latter detects virtually all the radiations scattered by the main detector. It does so without any loss due to the absorption of these radiations (a) by the metal walls of the enclosure usually containing the main detector and (b) by the walls of the auxiliary detector casing. It results from this that the detectors of the invention enable coincidence or anti-coincidence spectrometers with a very high performance to be made [fr

Test of the Weak Equivalence Principle using LIGO observations of GW150914 and Fermi observations of GBM transient 150914

Directory of Open Access Journals (Sweden)

Molin Liu

2017-07-01

Full Text Available About 0.4 s after the Laser Interferometer Gravitational-Wave Observatory (LIGO detected a transient gravitational-wave (GW signal GW150914, the Fermi Gamma-ray Burst Monitor (GBM also found a weak electromagnetic transient (GBM transient 150914. Time and location coincidences favor a possible association between GW150904 and GBM transient 150914. Under this possible association, we adopt Fermi's electromagnetic (EM localization and derive constraints on possible violations of the Weak Equivalence Principle (WEP from the observations of two events. Our calculations are based on four comparisons: (1 The first is the comparison of the initial GWs detected at the two LIGO sites. From the different polarizations of these initial GWs, we obtain a limit on any difference in the parametrized post-Newtonian (PPN parameter Δγ≲10−10. (2 The second is a comparison of GWs and possible EM waves. Using a traditional super-Eddington accretion model for GBM transient 150914, we again obtain an upper limit Δγ≲10−10. Compared with previous results for photons and neutrinos, our limits are five orders of magnitude stronger than those from PeV neutrinos in blazar flares, and seven orders stronger than those from MeV neutrinos in SN1987A. (3 The third is a comparison of GWs with different frequencies in the range [35 Hz, 250 Hz]. (4 The fourth is a comparison of EM waves with different energies in the range [1 keV, 10 MeV]. These last two comparisons lead to an even stronger limit, Δγ≲10−8. Our results highlight the potential of multi-messenger signals exploiting different emission channels to strengthen existing tests of the WEP.

The digital flat-panel X-Ray detectors

International Nuclear Information System (INIS)

Risticj, S. Goran

2013-01-01

In a digital imaging system, the incident x-ray image must be sampled both in the spatial and intensity dimensions. In the spatial dimensions, samples are obtained as averages of the intensity over picture elements or pixels. In the intensity dimension, the signal is digitalized into one of a finite number of levels or bits. Two main types of digital flat-panel detectors are based on the direct conversion, which contains the photoconductor, and on indirect conversion, which contains phosphor. The basics of these detectors are given. Coupling traditional x-ray detection material such as photoconductors and phosphors with a large-area active-matrix readout structure forms the basis of flat panel x-ray images. Active matrix technology provides a new, highly efficient, real time method for electronically storing and measuring the product of the x-ray interaction stage whether the product is visible wavelength photons or electrical charges. The direct and indirect detectors, made as the active-matrix flat-panel detectors containing sensing/storage elements, switching elements (diodes or thin film transistors (TFTS)) and image processing module, are described. Strengths and limitations of stimulable phosphors are discussed. The main advantages and disadvantages of mentioned x-ray detectors are also analyzed. (Author)

Model study of the impacts of future climate change on the hydrology of Ganges-Brahmaputra-Meghna (GBM) basin

Science.gov (United States)

Masood, M.; Yeh, P. J.-F.; Hanasaki, N.; Takeuchi, K.

2014-06-01

The intensity, duration, and geographic extent of floods in Bangladesh mostly depend on the combined influences of three river systems, Ganges, Brahmaputra and Meghna (GBM). In addition, climate change is likely to have significant effects on the hydrology and water resources of the GBM basins and might ultimately lead to more serious floods in Bangladesh. However, the assessment of climate change impacts on basin-scale hydrology by using well-constrained hydrologic modelling has rarely been conducted for GBM basins due to the lack of data for model calibration and validation. In this study, a macro-scale hydrologic model H08 has been applied regionally over the basin at a relatively fine grid resolution (10 km) by integrating the fine-resolution (~0.5 km) DEM data for accurate river networks delineation. The model has been calibrated via analyzing model parameter sensitivity and validated based on a long-term observed daily streamflow data. The impact of climate change on not only the runoff, but also the basin-scale hydrology including evapotranspiration, soil moisture and net radiation have been assessed in this study through three time-slice experiments; present-day (1979-2003), near-future (2015-2039) and far-future (2075-2099) periods. Results shows that, by the end of 21st century (a) the entire GBM basin is projected to be warmed by ~3°C (b) the changes of mean precipitation are projected to be +14.0, +10.4, and +15.2%, and the changes of mean runoff to be +14, +15, and +18% in the Brahmaputra, Ganges and Meghna basin respectively (c) evapotranspiration is predicted to increase significantly for the entire GBM basins (Brahmaputra: +14.4%, Ganges: +9.4%, Meghna: +8.8%) due to increased net radiation (Brahmaputra: +6%, Ganges: +5.9%, Meghna: +3.3%) as well as warmer air temperature. Changes of hydrologic variables will be larger in dry season (November-April) than that in wet season (May-October). Amongst three basins, Meghna shows the largest hydrological

First clinical results of a personalized immunotherapeutic vaccine against recurrent, incompletely resected, treatment-resistant glioblastoma multiforme (GBM) tumors, based on combined allo- and auto-immune tumor reactivity.

Science.gov (United States)

Schijns, Virgil E J C; Pretto, Chrystel; Devillers, Laurent; Pierre, Denis; Hofman, Florence M; Chen, Thomas C; Mespouille, Pascal; Hantos, Peter; Glorieux, Philippe; Bota, Daniela A; Stathopoulos, Apostolos

2015-05-28

Glioblastoma multiforme (GBM) patients have a poor prognosis. After tumor recurrence statistics suggest an imminent death within 1-4.5 months. Supportive preclinical data, from a rat model, provided the rational for a prototype clinical vaccine preparation, named Gliovac (or ERC 1671) composed of autologous antigens, derived from the patient's surgically removed tumor tissue, which is administered together with allogeneic antigens from glioma tissue resected from other GBM patients. We now report the first results of the Gliovac treatment for treatment-resistant GBM patients. Nine (9) recurrent GBM patients, after standard of care treatment, including surgery radio- and chemotherapy temozolomide, and for US patients, also bevacizumab (Avastin™), were treated under a compassionate use/hospital exemption protocol. Gliovac was given intradermally, together with human GM-CSF (Leukine(®)), and preceded by a regimen of regulatory T cell-depleting, low-dose cyclophosphamide. Gliovac administration in patients that have failed standard of care therapies showed minimal toxicity and enhanced overall survival (OS). Six-month (26 weeks) survival for the nine Gliovac patients was 100% versus 33% in control group. At week 40, the published overall survival was 10% if recurrent, reoperated patients were not treated. In the Gliovac treated group, the survival at 40 weeks was 77%. Our data suggest that Gliovac has low toxicity and a promising efficacy. A phase II trial has recently been initiated in recurrent, bevacizumab naïve GBM patients (NCT01903330). Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Silicon Strip Detectors for ATLAS at the HL-LHC Upgrade

CERN Document Server

Hara, K; The ATLAS collaboration

2012-01-01

The present ATLAS silicon strip (SCT) and transition radiation (TRT) trackers will be replaced with new silicon strip detectors, as part of the Inner Tracker System (ITK), for the Phase-2 upgrade of the Large Hadron Collider, HL-LHC. We have carried out intensive R&D programs to establish radiation harder strip detectors that can survive in a radiation level up to 3000 fb-1 of integrated luminosity based on n+-on-p microstrip detector. We describe main specifications for this year’s sensor fabrication, followed by a description of possible module integration schema

Lowering the background level and the energy threshold of Micromegas x-ray detectors for axion searches

CERN Document Server

Iguaz, F J; Aznar, F; Castel, J F; Dafni, T; Davenport, M; Ferrer-Ribas, E; Galan, J; Garcia, J A; Garza, J G; Giomataris, I; Irastorza, I G; Papaevangelou, T; Rodriguez, A; Tomas, A; Vafeiadis, T; Yildiz, S C

2014-01-01

Axion helioscopes search for solar axions by their conversion in x-rays in the presence of high magnetic fields. The use of low background x-ray detectors is an essential component contributing to the sensitivity of these searches. In this work, we review the recent advances on Micromegas detectors used in the CERN Axion Solar Telescope (CAST) and proposed for the future International Axion Observatory (IAXO). The actual setup in CAST has achieved background levels below 10$^{-6}$ keV$^{-1}$ cm$^{-2}$ s$^{-1}$, a factor 100 lower than the first generation of Micromegas detectors. This reduction is based on active and passive shielding techniques, the selection of radiopure materials, offline discrimination techniques and the high granularity of the readout. We describe in detail the background model of the detector, based on its operation at CAST site and at the Canfranc Underground Laboratory (LSC), as well as on Geant4 simulations. The best levels currently achieved at LSC are low than 10$^{-7}$ keV$^{-1}$ ...

Ultra Low Level Environmental Neutron Measurements Using Superheated Droplet Detectors

Energy Technology Data Exchange (ETDEWEB)

Fernandes, A.C. [Centro de Ciencias e Tecnologias Nucleares, Instituto Superior Tecnico, Universidade Tecnica de Lisboa, Estrada Nacional 10 - km 139.7, 2695-066 Bobadela LRS (Portugal); Centro de Fisica Nuclear, Universidade de Lisboa. Av. Prof. Gama Pinto, 2, 1649- 003 Lisboa (Portugal); Felizardo, M.; Girard, T.A.; Kling, A.; Ramos, A.R. [Centro de Fisica Nuclear, Universidade de Lisboa. Av. Prof. Gama Pinto, 2, 1649- 003 Lisboa (Portugal); Marques, J.G.; Prudencio, M.I.; Marques, R.; Carvalho, F.P. [Centro de Ciencias e Tecnologias Nucleares, Instituto Superior Tecnico, Universidade Tecnica de Lisboa, Estrada Nacional 10 - km 139.7, 2695-066 Bobadela LRS (Portugal)

2015-07-01

Through the application of superheated droplet detectors (SDDs), the SIMPLE project for the direct search for dark matter (DM) reached the most restrictive limits on the spin-dependent sector to date. The experiment is based on the detection of recoils following WIMP-nuclei interaction, mimicking those from neutron scattering. The thermodynamic operation conditions yield the SDDs intrinsically insensitive to radiations with linear energy transfer below ∼150 keVμm{sup -1} such as photons, electrons, muons and neutrons with energies below ∼40 keV. Underground facilities are increasingly employed for measurements in a low-level radiation background (DM search, gamma-spectroscopy, intrinsic soft-error rate measurements, etc.), where the rock overburden shields against cosmic radiation. In this environment the SDDs are sensitive only to α-particles and neutrons naturally emitted from the surrounding materials. Recently developed signal analysis techniques allow discrimination between neutron and α-induced signals. SDDs are therefore a promising instrument for low-level neutron and α measurements, namely environmental neutron measurements and α-contamination assays. In this work neutron measurements performed in the challenging conditions of the latest SIMPLE experiment (1500 mwe depth with 50-75 cm water shield) are reported. The results are compared with those obtained by detailed Monte Carlo simulations of the neutron background induced by {sup 238}U and {sup 232}Th traces in the facility, shielding and detector materials. Calculations of the neutron energy distribution yield the following neutron fluence rates (in 10{sup -8} cm{sup -2}s{sup -1}): thermal (<0.5 eV): 2.5; epithermal (0.5 eV-100 keV): 2.2; fast (>1 MeV): 3.9. Signal rates were derived using standard cross sections and codes routinely employed in reactor dosimetry. The measured and calculated neutron count rates per unit of active mass were 0.15 ct/kgd and 0.33 ct/kg-d respectively. As the major

Silicon carbide and its use as a radiation detector material

International Nuclear Information System (INIS)

Nava, F; Bertuccio, G; Cavallini, A; Vittone, E

2008-01-01

We present a comprehensive review of the properties of the epitaxial 4H silicon carbide polytype (4H–SiC). Particular emphasis is placed on those aspects of this material related to room, high-temperature and harsh environment ionizing radiation detector operation. A review of the characterization methods and electrical contacting issues and how these are related to detector performance is presented. The most recent data on charge transport parameters across the Schottky barrier and how these are related to radiation spectrometer performance are presented. Experimental results on pixel detectors having equivalent noise energies of 144 eV FWHM (7.8 electrons rms) and 196 eV FWHM at +27 °C and +100 °C, respectively, are reported. Results of studying the radiation resistance of 4H–SiC are analysed. The data on the ionization energies, capture cross section, deep-level centre concentrations and their plausible structures formed in SiC as a result of irradiation with various particles are reviewed. The emphasis is placed on the study of the 1 MeV neutron irradiation, since these thermal particles seem to play the main role in the detector degradation. An accurate electrical characterization of the induced deep-level centres by means of PICTS technique has allowed one to identify which play the main role in the detector degradation. (topical review)

Secondary particle in background levels and effects on detectors at future hadron colliders

International Nuclear Information System (INIS)

Pal, T.

1993-06-01

The next generation of hadron colliders, the Superconducting Super Collider (SSC) and the Large Hadron Collider (LHC), will operate at high center-of-mass energies and luminosities. Namely, for the SSC (LHC) √s = 40 TeV (√s = 16 TeV) and L = 10 33 cm -2 s -1 (L = 3 x 10 34 cm -2 s -1 ). These conditions will result in the production of large backgrounds as well as radiation environments. Ascertaining the backgrounds, in terms of the production of secondary charged and neutral particles, and the radiation environments are important considerations for the detectors proposed for these colliders. An initial investigation of the radiation levels in the SSC detectors was undertaken by D. Groom and colleagues, in the context of the ''task force on radiation levels in the SSC interaction regions.'' The method consisted essentially of an analytic approach, using standard descriptions of average events in conjunction with simulations of secondary processes. Following Groom's work, extensive Monte Carlo simulations were performed to address the issues of backgrounds and radiation environments for the GEM and SD C3 experiments proposed at the SSC, and for the ATLAS and CMS experiments planned for the LHC. The purpose of the present article is to give a brief summary of some aspects of the methods, assumptions, and calculations performed to date (principally for the SSC detectors), and to stress the relevance of such calculations to the detectors proposed for the study of B-physics in particular

Study of a Level-3 Tau Trigger with the Pixel Detector

CERN Document Server

Kotlinski, Danek; Nikitenko, Alexander

2001-01-01

We present a Monte Carlo study of the performance of a Level-3 Tau trigger based on the Pixel Detector data. The trigger is designed to select of the Higgs bosons decaying into two tau leptons with tau jet(s) in the final state. The proposed trigger is particularly useful as it operates at an early stage of the CMS High Level Trigger system. The performance of the trigger is studied for the most difficult case of high luminosity LHC scenario.

Neil Hayes, M.D., M.P.H., Explains TCGA Findings on GBM Subtypes - TCGA

Science.gov (United States)

New findings by researchers at UNC Lineberger Comprehensive Cancer Center suggest that the most common form of malignant brain cancer in adults, glioblastoma multiforme (GBM), is probably not a single disease but a set of diseases, each with a distinct underlying molecular disease process. The study was published by Cell Press in the January issue of the journal Cancer Cell and the researchers are part of the The Cancer Genome Atlas.

Secondary particle background levels and effects on detectors at future hadron colliders

International Nuclear Information System (INIS)

Pal, T.

1993-01-01

The next generation of hadron colliders, the Superconducting Super Collider (SSC) and the Large Hadron Collider (LHC), will operate at high center-of-mass energies and luminosities. Namely, for the SSC(LHC) √s=40TeV (√s=16TeV) and L=10 33 cm -2 s -1 (L=3x10 34 cm -2 s -1 ). These conditions will result in the production of large backgrounds as well as radiation environments. Ascertaining the backgrounds, in terms of the production of secondary charged and neutral particles, and the radiation environments are important considerations for the detectors proposed for these colliders. An initial investigation of the radiation levels in the SSC detectors was undertaken by D. Groom and colleagues, in the context of the open-quotes task force on radiation levels in the SSC interaction regions.close quotes The method consisted essentially of an analytic approach, using standard descriptions of average events in conjunction with simulations of secondary processes

Radiation detectors laboratory; Laboratorio de detectores de radiacion

Energy Technology Data Exchange (ETDEWEB)

Ramirez J, F.J. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

1997-07-01

The Radiation detectors laboratory was established with the assistance of the International Atomic Energy Agency which gave this the responsibility to provide its services at National and regional level for Latin America and it is located at the ININ. The more expensive and delicate radiation detectors are those made of semiconductor, so it has been put emphasis in the use and repairing of these detectors type. The supplied services by this laboratory are: selection consultant, detectors installation and handling and associated systems. Installation training, preventive and corrective maintenance of detectors and detection systems calibration. (Author)

SVD identifies transcript length distribution functions from DNA microarray data and reveals evolutionary forces globally affecting GBM metabolism.

Directory of Open Access Journals (Sweden)

Nicolas M Bertagnolli

Full Text Available To search for evolutionary forces that might act upon transcript length, we use the singular value decomposition (SVD to identify the length distribution functions of sets and subsets of human and yeast transcripts from profiles of mRNA abundance levels across gel electrophoresis migration distances that were previously measured by DNA microarrays. We show that the SVD identifies the transcript length distribution functions as "asymmetric generalized coherent states" from the DNA microarray data and with no a-priori assumptions. Comparing subsets of human and yeast transcripts of the same gene ontology annotations, we find that in both disparate eukaryotes, transcripts involved in protein synthesis or mitochondrial metabolism are significantly shorter than typical, and in particular, significantly shorter than those involved in glucose metabolism. Comparing the subsets of human transcripts that are overexpressed in glioblastoma multiforme (GBM or normal brain tissue samples from The Cancer Genome Atlas, we find that GBM maintains normal brain overexpression of significantly short transcripts, enriched in transcripts that are involved in protein synthesis or mitochondrial metabolism, but suppresses normal overexpression of significantly longer transcripts, enriched in transcripts that are involved in glucose metabolism and brain activity. These global relations among transcript length, cellular metabolism and tumor development suggest a previously unrecognized physical mode for tumor and normal cells to differentially regulate metabolism in a transcript length-dependent manner. The identified distribution functions support a previous hypothesis from mathematical modeling of evolutionary forces that act upon transcript length in the manner of the restoring force of the harmonic oscillator.

Detectors for Linear Colliders: Detector design for a Future Electron-Positron Collider (4/4)

CERN Multimedia

CERN. Geneva

2010-01-01

In this lecture I will discuss the issues related to the overall design and optimization of a detector for ILC and CLIC energies. I will concentrate on the two main detector concepts which are being developed in the context of the ILC. Here there has been much recent progress in developing realistic detector models and in understanding the physics performance of the overall detector concept. In addition, I will discuss the how the differences in the detector requirements for the ILC and CLIC impact the overall detector design.

Background level of natural radioactivities in a giant water Cherenkov detector and its surrounding environment; KAMIOKANDE-II

Energy Technology Data Exchange (ETDEWEB)

Yamamoto, Masayoshi; Sakanoue, Masanobu; Komura, Kazuhisa; Ueno, Kaoru [Kanazawa Univ., Tatsunokuchi, Ishikawa (Japan). Low Level Radioactivity Lab.

1989-12-01

The KAMIOKANDE-II water Cherenkov detector for the measurement of nucleon decay and/or solar neutrino has been operating in the underground laboratory at a depth of 2,700 m.w.e. (meter water equivalent) in Kamioka mine of Gifu Prefecture. Concentrations of {sup 238}U, {sup 232}Th, {sup 226}Ra and {sup 222}Rn as the major background sources have been measured for various kinds of rocks, mine water, mine air and high purity water used as a detector during the period from August 1986 to December 1987. The concentration levels of these radionuclides and their seasonal variation have become clear. Some of these results have provided useful informations for decreasing the background level of water Cherenkov detector. (author).

Fast method for geometric calibration of detectors and matching testing between two detectors

International Nuclear Information System (INIS)

Pechenova, O.Yu.

2002-01-01

A fast method of geometric calibration of detectors has been proposed. The main idea of this method is to determine offsets by fitting the real data distribution by analytic functions which describe the motion of one detector relative to the other one. This method can be applicable to offsets determination for one detector relative to the other detector or for one part of the detector relative to its other part. The detectors should be placed perpendicular to the beam axis. The form of analytic functions depends on the geometry of the experiment and direction of the coordinate axes. The analytic functions have been obtained using the rotation matrices. This method can be applied to the matching testing between two detectors

HPGe detector shielding adjustment

International Nuclear Information System (INIS)

Trnkova, L.; Rulik, P.

2008-01-01

Low-level background shielding of HPGe detectors is used mainly for environmental samples with very low content of radionuclides. National Radiation Protection Institute (SURO) in Prague is equipped with 14 HPGe detectors with relative efficiency up to 150%. The detectors are placed in a room built from materials with low content of natural radionuclides and equipped with a double isolation of the floor against radon. Detectors themselves are placed in lead or steel shielding. Steel shielding with one of these detectors with relative efficiency of 100% was chosen to be rebuilt to achieve lower minimum detectable activity (MDA). Additional lead and copper shielding was built up inside the original steel shielding to reduce the volume of the inner space and filled with nitrogen by means of evaporating liquid nitrogen. The additional lead and copper shielding, consequent reduction of the inner volume and supply of evaporated nitrogen, caused a decrease of the background count and accordingly MDA values as well. The effect of nitrogen evaporation on the net areas of peaks belonging to radon daughters is significant. The enhanced shielding adjustment has the biggest influence in low energy range, what can be seen in collected data. MDA values in energy range from 30 keV to 400 keV decreased to 0.65-0.85 of original value, in energy range from 400 keV to 2 MeV they fell to 0.70-0.97 of original value. (authors)

The Borexino Detector

Science.gov (United States)

Montanari, David

2010-04-01

The Borexino detector is a large volume liquid scintillator detector for low energy neutrino spetroscopy currently running underground at the Laboratori Nazionali del Gran Sasso, Italy. Main goal of the experiment is the real-time measurement of sub-MeV solar neutrinos, and particularly of the mono-energetic (862KeV) 7Be electron capture neutrinos, via neutrino-electron scattering in ultra-pure liquid scintillator. We report the description of the detector itself from its construction to the final current configuration. The initial requirements are first presented, then the strategy developed to achieve them: choice of materials and components, purification of the scintillator, cleaning, leak tightness, fluid handling. Every single point is analyzed, particularly the purification plants, that allowed reaching an ultra high pure scintillator and the fluid handling system, a large modular system connecting fluid receiving, purification and fluid delivery processes for every fluid involved. The different phases of the filling follow: from air to water to the final liquid scintillator, mainly focusing on the scintillator filling. The performances of the detector and the results are then presented.

MUON DETECTORS: RPC

CERN Multimedia

P. Paolucci

2012-01-01

The RPC system is operating with a very high uptime, an average chamber efficiency of about 95% and an average cluster size around 1.8. The average number of active channels is 97.7%. Eight chambers are disconnected and forty are working in single-gap mode due to high-voltage problems. The total luminosity lost due to RPCs in 2012 is 88.46 pb–1. One of the main goals of 2012 was to improve the stability of the endcap trigger that is strongly correlated to the performances of the detector, due to the 3-out-3 trigger logic. At beginning of 2011 the instability of the detector efficiency was about 10%. Detailed studies found that this was mainly due to the strong correlation between the performance of the detector and the atmospheric pressure (P). Figure XXY shows the linear correlation between the average cluster size of the endcap chamber versus P. This effect is expected for gaseous detectors and can be reduced by correcting the applied high-voltage working point (HVapp) according to the followi...

Baby-MIND neutrino detector

Science.gov (United States)

Mefodiev, A. V.; Kudenko, Yu. G.; Mineev, O. V.; Khotjantsev, A. N.

2017-11-01

The main objective of the Baby-MIND detector (Magnetized Iron Neutrino Detector) is the study of muon charge identification efficiency for muon momenta from 0.3 to 5 GeV/ c. This paper presents the results of measurement of the Baby-MIND parameters.

Guide to the Main Ring DO overpass

International Nuclear Information System (INIS)

Turkot, F.

1985-01-01

The DO overpass is a modification of the beam orbit in Main Ring in order to better accommodate a Tevatron collider detector at DO. The orbit is moved up approx. 51 inches over most of the long straight section at DO, thus making the Main Ring the world's first non-planar proton synchrotron. A similar overpass, but with four times the displacement, is planned for the CDF detector at the BO straight section. The nominal separation between the beam orbit in the Main Ring and the orbit in the Tevatron is 25.5 inches. Early in the design study of a detector that would utilize the Tevatron is a anti pp collider, it was apparent that a larger separation at the detector was highly desirable. In 1981, Tom Collins proposed a specific lattice geometry in the Main Ring for achieving larger separation, called ''the screw beam''. His proposal has served as the basis for the design of both the BO and DO overpasses. The main purpose of this report is to describe in some detail the implementation of the DO overpass. Topics to be covered include: (a) geometry of the overpass orbit, (b) the new hardware in the tunnel, (c) the power supply system, (d) the control facility, (e) accelerator beam dynamics ramifications, and (f) commissioning experience. A secondary purpose is to provide a fairly complete ''bibliography'' to the sources of information on the overpass. 17 refs., 17 figs

Silicon Strip Detectors for ATLAS at the HL-LHC Upgrade

CERN Document Server

Hara, K; The ATLAS collaboration

2012-01-01

present ATLAS silicon strip tracker (SCT) and transition radiation tracker(TRT) are to be replaced with new silicon strip detectors as part of the Inner Tracker System (ITK) for the Phase-II upgrade of the Large Hadron Collider, HL-LHC. We have carried out intensive R&D programs based on n+-on-p microstrip detectors to fabricate improved radiation hard strip detectors that can survive the radiation levels corresponding to the integrated luminosity of up to 3000 fb−1. We describe the main specifications for this year’s sensor fabrication and the related R&D results, followed by a description of the candidate schema for module integration.

ANCA-GBM dot-blot : Evaluation of an assay in the differential diagnosis of patients presenting with rapidly progressive glomerulonephritis

NARCIS (Netherlands)

Rutgers, Abraham; Damoiseaux, Jan; Roozendaal, Caroline; Limburg, Pieter C; Stegeman, Coen A; Tervaert, Jan Willem Cohen

Rapidly progressive glomerulonephritis (RPGN) is characterized by rapid and progressive loss of renal function and the presence of crescentic glomerulonephritis (CGN). Early diagnosis and appropriate treatment is mandatory to prevent death and/or renal failure. We have evaluated an ANCA-GBM dot-blot

The DELPHI Detector (DEtector with Lepton Photon and Hadron Identification)

CERN Multimedia

Crawley, B; Munich, K; Mckay, R; Matorras, F; Joram, C; Malychev, V; Behrmann, A; Van dam, P; Drees, J K; Stocchi, A; Adam, W; Booth, P; Bilenki, M; Rosenberg, E I; Morton, G; Rames, J; Hahn, S; Cosme, G; Ventura, L; Marco, J; Tortosa martinez, P; Monge silvestri, R; Moreno, S; Phillips, H; Alekseev, G; Boudinov, E; Martinez rivero, C; Gitarskiy, L; Davenport, M; De clercq, C; Firestone, A; Myagkov, A; Belous, K; Haider, S; Hamilton, K M; Lamsa, J; Rahmani, M H; Malek, A; Hughes, G J; Peralta, L; Carroll, L; Fuster verdu, J A; Cossutti, F; Gorn, L; Yi, J I; Bertrand, D; Myatt, G; Richard, F; Shapkin, M; Hahn, F; Ferrer soria, A; Reinhardt, R; Renton, P; Sekulin, R; Timmermans, J; Baillon, P

2002-01-01

% DELPHI The DELPHI Detector (Detector with Lepton Photon and Hadron Identification) \\\\ \\\\DELPHI is a general purpose detector for physics at LEP on and above the Z$^0$, offering three-dimensional information on curvature and energy deposition with fine spatial granularity as well as identification of leptons and hadrons over most of the solid angle. A superconducting coil provides a 1.2~T solenoidal field of high uniformity. Tracking relies on the silicon vertex detector, the inner detector, the Time Projection Chamber (TPC), the outer detector and forward drift chambers. Electromagnetic showers are measured in the barrel with high granularity by the High Density Projection Chamber (HPC) and in the endcaps by $ 1 ^0 $~x~$ 1 ^0 $ projective towers composed of lead glass as active material and phototriode read-out. Hadron identification is provided mainly by liquid and gas Ring Imaging Counters (RICH). The instrumented magnet yoke serves for hadron calorimetry and as filter for muons, which are identified in t...

GRAVITATIONAL-WAVE OBSERVATIONS MAY CONSTRAIN GAMMA-RAY BURST MODELS: THE CASE OF GW150914–GBM

Energy Technology Data Exchange (ETDEWEB)

Veres, P. [CSPAR, University of Alabama in Huntsville, 320 Sparkman Dr., Huntsville, AL 35805 (United States); Preece, R. D. [Dept. of Space Science, University of Alabama in Huntsville, 320 Sparkman Dr., Huntsville, AL 35805 (United States); Goldstein, A.; Connaughton, V. [Universities Space Research Association, 320 Sparkman Dr. Huntsville, AL 35806 (United States); Mészáros, P. [Dept. of Astronomy and Astrophysics, Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802 (United States); Burns, E., E-mail: peter.veres@uah.edu [Physics Dept., University of Alabama in Huntsville, 320 Sparkman Dr., Huntsville, AL 35805 (United States)

2016-08-20

The possible short gamma-ray burst (GRB) observed by Fermi /GBM in coincidence with the first gravitational-wave (GW) detection offers new ways to test GRB prompt emission models. GW observations provide previously inaccessible physical parameters for the black hole central engine such as its horizon radius and rotation parameter. Using a minimum jet launching radius from the Advanced LIGO measurement of GW 150914, we calculate photospheric and internal shock models and find that they are marginally inconsistent with the GBM data, but cannot be definitely ruled out. Dissipative photosphere models, however, have no problem explaining the observations. Based on the peak energy and the observed flux, we find that the external shock model gives a natural explanation, suggesting a low interstellar density (∼10{sup −3} cm{sup −3}) and a high Lorentz factor (∼2000). We only speculate on the exact nature of the system producing the gamma-rays, and study the parameter space of a generic Blandford–Znajek model. If future joint observations confirm the GW–short-GRB association we can provide similar but more detailed tests for prompt emission models.

Detector unit for X-ray diagnosis

International Nuclear Information System (INIS)

Svobodova, B.; Hamouz, J.; Pavlicek, Z.; Jursova, L.; Pohanka, J.

1983-01-01

The detector unit is applied in the medical and industrial X-ray diagnosis and analysis. It controls the X-ray dosing by exposure and brightness automation. The detector field is generated from a carrier, in which detector elements with light quides are situated, tapped on optical detectors with level converters outside the detector field. The detector field and the optical detectors with level converters are located in a light-resistent shell. This arrangement of the detector unit allows to use the impulse skiascopy instead of permanent X-ray examinations or the skiagraphy with multienergy levels which considerably improves the diagnostic value of the exposures and the working conditions. 1 cl., 1 fig

Connective tissue growth factor (CTGF/CCN2 is negatively regulated during neuron-glioblastoma interaction.

Directory of Open Access Journals (Sweden)

Luciana F Romão

Full Text Available Connective-tissue growth factor (CTGF/CCN2 is a matricellular-secreted protein involved in complex processes such as wound healing, angiogenesis, fibrosis and metastasis, in the regulation of cell proliferation, migration and extracellular matrix remodeling. Glioblastoma (GBM is the major malignant primary brain tumor and its adaptation to the central nervous system microenvironment requires the production and remodeling of the extracellular matrix. Previously, we published an in vitro approach to test if neurons can influence the expression of the GBM extracellular matrix. We demonstrated that neurons remodeled glioma cell laminin. The present study shows that neurons are also able to modulate CTGF expression in GBM. CTGF immnoreactivity and mRNA levels in GBM cells are dramatically decreased when these cells are co-cultured with neonatal neurons. As proof of particular neuron effects, neonatal neurons co-cultured onto GBM cells also inhibit the reporter luciferase activity under control of the CTGF promoter, suggesting inhibition at the transcription level. This inhibition seems to be contact-mediated, since conditioned media from embryonic or neonatal neurons do not affect CTGF expression in GBM cells. Furthermore, the inhibition of CTGF expression in GBM/neuronal co-cultures seems to affect the two main signaling pathways related to CTGF. We observed inhibition of TGFβ luciferase reporter assay; however phopho-SMAD2 levels did not change in these co-cultures. In addition levels of phospho-p44/42 MAPK were decreased in co-cultured GBM cells. Finally, in transwell migration assay, CTGF siRNA transfected GBM cells or GBM cells co-cultured with neurons showed a decrease in the migration rate compared to controls. Previous data regarding laminin and these results demonstrating that CTGF is down-regulated in GBM cells co-cultured with neonatal neurons points out an interesting view in the understanding of the tumor and cerebral microenvironment

Asymmetric Data Acquisition System for an Endoscopic PET-US Detector

Science.gov (United States)

Zorraquino, Carlos; Bugalho, Ricardo; Rolo, Manuel; Silva, Jose C.; Vecklans, Viesturs; Silva, Rui; Ortigão, Catarina; Neves, Jorge A.; Tavernier, Stefaan; Guerra, Pedro; Santos, Andres; Varela, João

2016-02-01

According to current prognosis studies of pancreatic cancer, survival rate nowadays is still as low as 6% mainly due to late detections. Taking into account the location of the disease within the body and making use of the level of miniaturization in radiation detectors that can be achieved at the present time, EndoTOFPET-US collaboration aims at the development of a multimodal imaging technique for endoscopic pancreas exams that combines the benefits of high resolution metabolic information from time-of- flight (TOF) positron emission tomography (PET) with anatomical information from ultrasound (US). A system with such capabilities calls for an application-specific high-performance data acquisition system (DAQ) able to control and readout data from different detectors. The system is composed of two novel detectors: a PET head extension for a commercial US endoscope placed internally close to the region-of-interest (ROI) and a PET plate placed over the patient's abdomen in coincidence with the PET head. These two detectors will send asymmetric data streams that need to be handled by the DAQ system. The approach chosen to cope with these needs goes through the implementation of a DAQ capable of performing multi-level triggering and which is distributed across two different on-detector electronics and the off-detector electronics placed inside the reconstruction workstation. This manuscript provides an overview on the design of this innovative DAQ system and, based on results obtained by means of final prototypes of the two detectors and DAQ, we conclude that a distributed multi-level triggering DAQ system is suitable for endoscopic PET detectors and it shows potential for its application in different scenarios with asymmetric sources of data.

Study of a spherical gaseous detector for research of rare events at low energy threshold

International Nuclear Information System (INIS)

Dastgheibi-Fard, Ali

2014-01-01

The Spherical gaseous detector (or Spherical Proportional Counter, SPC) is a novel type of a particle detector, with a broad range of applications. Its main features include a very low energy threshold which is independent of the volume (due to its very low capacitance), a good energy resolution, robustness and a single detection readout channel. SEDINE, a low background detector installed at the underground site of Laboratoire Souterrain de Modane is currently being operated and aims at measuring events at a very low energy threshold, around 40 eV. The sensitivity for the rare events detection at low energy is correlated to the detector background and to the decreasing the level of energy threshold, which was the main point of this thesis. A major effort has been devoted to the operating of the experimental detector. Several detection parameters were optimized: the electric field homogeneity in the sphere, keeping clear of sparks, the electronic noise level and the leak rate of the detector. The detector is optimized for operation with a high pressure stable gain. The modification of the shield, cleanings of the detector and the addition of an anti-Radon tent have significantly reduced the background of SEDINE. Progress has increased the sensitivity of the detector at low energy up to a value comparable to the results other underground research experiences for the low mass WIMPs. We will present the results with a measured background in the region of keV, which has allowed us to show a competitive figure of exclusion for the production of light dark matter. (author) [fr

Large solid angle detectors (low energy)

International Nuclear Information System (INIS)

L'Hote, D.

1988-01-01

This lecture deals with large solid angle detectors used in low energy experiments (mainly in Nuclear Physics). The reasons for using such detectors are discussed, and several basic principles of their design are presented. Finally, two examples of data analysis from such detectors are given [fr

Detectors of Cosmic Rays, Gamma Rays, and Neutrinos

International Nuclear Information System (INIS)

Altamirano, A.; Navarra, G.

2009-01-01

We summarize the main features, properties and performances of the typical detectors in use in Cosmic Ray Physics. A brief historical and general introduction will focus on the main classes and requirements of such detectors.

Epidermal growth factor receptor (EGFR mutation status and Rad51 determine the response of glioblastoma (GBM to multimodality therapy with cetuximab, temozolomide and radiation

Directory of Open Access Journals (Sweden)

Phyllis Rachelle Wachsberger

2013-02-01

Full Text Available Purpose: EGFR amplification and mutation (i.e., EGFRvIII are found in 40% of primary GBM tumors and are believed to contribute to tumor development and therapeutic resistance. This study was designed to investigate how EGFR mutational status modulates response to multimodality treatment with cetuximab, an anti-EGFR inhibitor, the chemotherapeutic agent, temozolamide (TMZ and radiation therapy (RT Methods and Materials: In vitro and in vivo experiments were performed on two isogenic U87 GBM cell lines: one overexpressing wildtype EGFR (U87wtEGFR and the other overexpressing EGFRvIII (U87EGFRvIII. Results: Xenografts harboring EGFRvIII were more sensitive to TMZ alone and TMZ in combination with RT and/or cetuximab than xenografts expressing wtEGFR. In vitro experiments demonstrated that U87EGFRvIII-expressing tumors appear to harbor defective DNA homologous recombination repair in the form of Rad51 processing, Conclusions: The difference in sensitivity between EGFR-expressing and EGFRvIII-expressing tumors to combined modality treatment may help in the future tailoring of GBM therapy to subsets of patients expressing more or less of the EGFR mutant.

Smile detectors correlation

Science.gov (United States)

Yuksel, Kivanc; Chang, Xin; Skarbek, Władysław

2017-08-01

The novel smile recognition algorithm is presented based on extraction of 68 facial salient points (fp68) using the ensemble of regression trees. The smile detector exploits the Support Vector Machine linear model. It is trained with few hundreds exemplar images by SVM algorithm working in 136 dimensional space. It is shown by the strict statistical data analysis that such geometric detector strongly depends on the geometry of mouth opening area, measured by triangulation of outer lip contour. To this goal two Bayesian detectors were developed and compared with SVM detector. The first uses the mouth area in 2D image, while the second refers to the mouth area in 3D animated face model. The 3D modeling is based on Candide-3 model and it is performed in real time along with three smile detectors and statistics estimators. The mouth area/Bayesian detectors exhibit high correlation with fp68/SVM detector in a range [0:8; 1:0], depending mainly on light conditions and individual features with advantage of 3D technique, especially in hard light conditions.

Establishment, maintenance and in vitro and in vivo applications of primary human glioblastoma multiforme (GBM) xenograft models for translational biology studies and drug discovery.

Science.gov (United States)

Carlson, Brett L; Pokorny, Jenny L; Schroeder, Mark A; Sarkaria, Jann N

2011-03-01

Development of clinically relevant tumor model systems for glioblastoma multiforme (GBM) is important for advancement of basic and translational biology. One model that has gained wide acceptance in the neuro-oncology community is the primary xenograft model. This model entails the engraftment of patient tumor specimens into the flank of nude mice and subsequent serial passage of these tumors in the flank of mice. These tumors are then used to establish short-term explant cultures or intracranial xenografts. This unit describes detailed procedures for establishment, maintenance, and utilization of a primary GBM xenograft panel for the purpose of using them as tumor models for basic or translational studies.

Combined VEGF and CXCR4 antagonism targets the GBM stem cell population and synergistically improves survival in an intracranial mouse model of glioblastoma.

Science.gov (United States)

Barone, Amy; Sengupta, Rajarshi; Warrington, Nicole M; Smith, Erin; Wen, Patrick Y; Brekken, Rolf A; Romagnoli, Barbara; Douglas, Garry; Chevalier, Eric; Bauer, Michael P; Dembowsky, Klaus; Piwnica-Worms, David; Rubin, Joshua B

2014-10-30

Glioblastoma recurrence involves the persistence of a subpopulation of cells with enhanced tumor-initiating capacity (TIC) that reside within the perivascular space, or niche (PVN). Anti-angiogenic therapies may prevent the formation of new PVN but have not prevented recurrence in clinical trials, suggesting they cannot abrogate TIC activity. We hypothesized that combining anti-angiogenic therapy with blockade of PVN function would have superior anti-tumor activity. We tested this hypothesis in an established intracranial xenograft model of GBM using a monoclonal antibody specific for murine and human VEGF (mcr84) and a Protein Epitope Mimetic (PEM) CXCR4 antagonist, POL5551. When doses of POL5551 were increased to overcome an mcr84-induced improvement in vascular barrier function, combinatorial therapy significantly inhibited intracranial tumor growth and improved survival. Anti-tumor activity was associated with significant changes in tumor cell proliferation and apoptosis, and a reduction in the numbers of perivascular cells expressing the TIC marker nestin. A direct effect on TICs was demonstrated for POL5551, but not mcr84, in three primary patient-derived GBM isolates. These findings indicate that targeting the structure and function of the PVN has superior anti-tumor effect and provide a strong rationale for clinical evaluation of POL5551 and Avastin in patients with GBM.

Low level radioactivity measurements with phoswich detectors using coincident techniques and digital pulse processing analysis.

Science.gov (United States)

de la Fuente, R; de Celis, B; del Canto, V; Lumbreras, J M; de Celis Alonso, B; Martín-Martín, A; Gutierrez-Villanueva, J L

2008-10-01

A new system has been developed for the detection of low radioactivity levels of fission products and actinides using coincidence techniques. The device combines a phoswich detector for alpha/beta/gamma-ray recognition with a fast digital card for electronic pulse analysis. The phoswich can be used in a coincident mode by identifying the composed signal produced by the simultaneous detection of alpha/beta particles and X-rays/gamma particles. The technique of coincidences with phoswich detectors was proposed recently to verify the Nuclear Test Ban Treaty (NTBT) which established the necessity of monitoring low levels of gaseous fission products produced by underground nuclear explosions. With the device proposed here it is possible to identify the coincidence events and determine the energy and type of coincident particles. The sensitivity of the system has been improved by employing liquid scintillators and a high resolution low energy germanium detector. In this case it is possible to identify simultaneously by alpha/gamma coincidence transuranic nuclides present in environmental samples without necessity of performing radiochemical separation. The minimum detectable activity was estimated to be 0.01 Bq kg(-1) for 0.1 kg of soil and 1000 min counting.

Low level radioactivity measurements with phoswich detectors using coincident techniques and digital pulse processing analysis

International Nuclear Information System (INIS)

Fuente, R. de la; Celis, B. de; Canto, V. del; Lumbreras, J.M.; Celis, Alonso B. de; Martin-Martin, A.; Gutierrez-Villanueva, J.L.

2008-01-01

A new system has been developed for the detection of low radioactivity levels of fission products and actinides using coincidence techniques. The device combines a phoswich detector for α/β/γ-ray recognition with a fast digital card for electronic pulse analysis. The phoswich can be used in a coincident mode by identifying the composed signal produced by the simultaneous detection of α/β particles and X-rays/γ particles. The technique of coincidences with phoswich detectors was proposed recently to verify the Nuclear Test Ban Treaty (NTBT) which established the necessity of monitoring low levels of gaseous fission products produced by underground nuclear explosions. With the device proposed here it is possible to identify the coincidence events and determine the energy and type of coincident particles. The sensitivity of the system has been improved by employing liquid scintillators and a high resolution low energy germanium detector. In this case it is possible to identify simultaneously by α/γ coincidence transuranic nuclides present in environmental samples without necessity of performing radiochemical separation. The minimum detectable activity was estimated to be 0.01 Bq kg -1 for 0.1 kg of soil and 1000 min counting

Applications of the Long-Range Alpha Detector (LRAD) technology to low-level radioactive waste management

International Nuclear Information System (INIS)

Johnson, J.D.; Allander, K.S.; Bounds, J.A.; Garner, S.E.; Johnson, J.P.; MacArthur, D.W.

1993-01-01

Long-Range Alpha Detector (LRAD) systems are designed to monitor alpha contamination by measuring the number of ions in the air. Alpha particles are a form of ionizing radiation and a typical 5-MeV alpha particle will create about 150,000 ion pairs in air. Field tests at various DOE sites have shown that LRAD Surface Soil Monitors (SSM), Sample Monitors, and Object Monitors are faster and more sensitive than traditional alpha detectors for measuring alpha contamination. This paper discusses the various applications of LRAD technology to low-level radioactive waste management

Calculation of Excore Detector Responses upon Control Rods Movement in PGSFR

Energy Technology Data Exchange (ETDEWEB)

Ha, Pham Nhu Viet; Lee, Min Jae; Kang, Chang Moo; Kim, Sang Ji [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-05-15

The Prototype Generation-IV Sodium-cooled Fast Reactor (PGSFR) safety design concept, which aims at achieving IAEA's safety objectives and GIF's safety goals for Generation-IV reactor systems, is mainly focused on the defense in depth for accident detection, prevention, control, mitigation and termination. In practice, excore neutron detectors are widely used to determine the spatial power distribution and power level in a nuclear reactor core. Based on the excore detector signals, the reactor control and protection systems infer the corresponding core power and then provide appropriate actions for safe and reliable reactor operation. To this end, robust reactor power monitoring, control and core protection systems are indispensable to prevent accidents and reduce its detrimental effect should one occur. To design such power monitoring and control systems, numerical investigation of excore neutron detector responses upon various changes in the core power level/distribution and reactor conditions is required in advance. In this study, numerical analysis of excore neutron detector responses (DRs) upon control rods (CRs) movement in PGSFR was carried out. The objective is to examine the sensitivity of excore neutron detectors to the core power change induced by moving CRs and thereby recommend appropriate locations to locate excore neutron detectors for the designing process of the PGSFR power monitoring systems. Section 2 describes the PGSFR core model and calculation method as well as the numerical results for the excore detector spatial weighting functions, core power changes and detector responses upon various scenarios of moving CRs in PGSFR. The top detector is conservatively safe because it overestimated the core power level. However, the lower and bottom detectors still functioned well in this case because they exhibited a minor underestimation of core power of less than ∼0.5%. As a secondary CR was dropped into the core, the lower detector was

Low-level radon measurements by nuclear track detectors

International Nuclear Information System (INIS)

Koksal, E. M.; Goksel, S. A.; Alkan, H.

1985-01-01

In the work to be described here we have developed a passive nuclear track dosimeter to measure the integrated value of indoor radon (Rn-222) over a long period of time. Passive radon dosimeter which we have developed in our laboratories makes use of two small pieces of CR-39 plastic (Allyl diglycol carbonate) as detectors for registering tracks of alpha particles emitted by radon. These CR-39 plastic detectors are fixed on the inside bottom of a cup-shaped polystrene enclosure which is closed at the top by a tissue permeable for gases only. CR-39 detectors exposed to radon gas in the indoor air for a period of six months then are removed and chemically etched to make the alpha particle tracks visible under the microscope. The counts of tracks are evaluated to determine the radon concentration in the air in comparison with the number of tracks produced by a known concentration of radon gas. By using the passive dosimeters developed and the chemical etching procedure descriped here, measurements of indoor radon concentrations were carried out in 45 houses in different districts of the city of Istanbul. In this pilot experiment mean radon concentrations between 0.7 and 3.5 pCi/l have been found in these houses. In order to improve the counting of alpha tracks produced on the detectors a prototype electrochemical etching system in addition to chemical etching, is being developed. (author)

A Chip-Level BSOR-Based Linear GSIC Multiuser Detector for Long-Code CDMA Systems

Directory of Open Access Journals (Sweden)

Benyoucef M

2007-01-01

Full Text Available We introduce a chip-level linear group-wise successive interference cancellation (GSIC multiuser structure that is asymptotically equivalent to block successive over-relaxation (BSOR iteration, which is known to outperform the conventional block Gauss-Seidel iteration by an order of magnitude in terms of convergence speed. The main advantage of the proposed scheme is that it uses directly the spreading codes instead of the cross-correlation matrix and thus does not require the calculation of the cross-correlation matrix (requires floating point operations (flops, where is the processing gain and is the number of users which reduces significantly the overall computational complexity. Thus it is suitable for long-code CDMA systems such as IS-95 and UMTS where the cross-correlation matrix is changing every symbol. We study the convergence behavior of the proposed scheme using two approaches and prove that it converges to the decorrelator detector if the over-relaxation factor is in the interval ]0, 2[. Simulation results are in excellent agreement with theory.

A Chip-Level BSOR-Based Linear GSIC Multiuser Detector for Long-Code CDMA Systems

Directory of Open Access Journals (Sweden)

M. Benyoucef

2008-01-01

Full Text Available We introduce a chip-level linear group-wise successive interference cancellation (GSIC multiuser structure that is asymptotically equivalent to block successive over-relaxation (BSOR iteration, which is known to outperform the conventional block Gauss-Seidel iteration by an order of magnitude in terms of convergence speed. The main advantage of the proposed scheme is that it uses directly the spreading codes instead of the cross-correlation matrix and thus does not require the calculation of the cross-correlation matrix (requires 2NK2 floating point operations (flops, where N is the processing gain and K is the number of users which reduces significantly the overall computational complexity. Thus it is suitable for long-code CDMA systems such as IS-95 and UMTS where the cross-correlation matrix is changing every symbol. We study the convergence behavior of the proposed scheme using two approaches and prove that it converges to the decorrelator detector if the over-relaxation factor is in the interval ]0, 2[. Simulation results are in excellent agreement with theory.

The CRESST-III detector module

Energy Technology Data Exchange (ETDEWEB)

Wuestrich, Marc [Max-Planck-Institut f. Physik (Werner-Heisenberg-Institut) (Germany); Collaboration: CRESST-Collaboration

2016-07-01

The direct dark matter experiment CRESST uses scintillating calorimeters to detected WIMP induced nuclear scattering in CaWO{sub 4} single crystals. Equipped with transition edge sensors (TESs), these detectors can achieve detection thresholds well below 1 keV. The last physics run of CRESST-II proved the high potential of the experiment especially for small WIMP masses and triggered the development of a new detector module using much smaller CaWO{sub 4} main absorbers. The upcoming CRESST-III run will mainly be equipped with these newly developed modules, which combine a fully scintillating detector housing with an improved detection threshold (<100 keV). While many features of the new module were adapted from previous module designs in an improved way, also new features are implemented like instrumented sticks (iSticks) holding the crystals and optimized TES structures for phonon and light detectors. First tests above ground validated the improved performance of these detector modules and promise to explore new regions in the WIMP parameter space in the next CRESST-III run.

Radiation detectors laboratory

International Nuclear Information System (INIS)

Ramirez J, F.J.

1997-01-01

The Radiation detectors laboratory was established with the assistance of the International Atomic Energy Agency which gave this the responsibility to provide its services at National and regional level for Latin America and it is located at the ININ. The more expensive and delicate radiation detectors are those made of semiconductor, so it has been put emphasis in the use and repairing of these detectors type. The supplied services by this laboratory are: selection consultant, detectors installation and handling and associated systems. Installation training, preventive and corrective maintenance of detectors and detection systems calibration. (Author)

The LUCID-2 Detector

CERN Document Server

Soluk, Richard; The ATLAS collaboration

2017-01-01

The LUCID-2 detector is the main online and offline luminosity provider of the ATLAS experiment. It provides over 100 different luminosity measurements from different algorithms for each of the 2808 LHC bunches. LUCID was entirely redesigned in preparation for LHC Run 2: both the detector and the electronics were upgraded in order to cope with the challenging conditions expected at the LHC center of mass energy of 13 TeV with only 25 ns bunch-spacing. While LUCID-1 used gas as a Cherenkov medium, the LUCID-2 detector is in a new unique way using the quartz windows of small photomultipliers as the Cherenkov medium. The main challenge for a luminometer is to keep the efficiency constant during years of data-taking. LUCID-2 is using an innovative calibration system based on radioactive 207 Bi sources deposited on the quartz window of the readout photomultipliers. This makes it possible to accurately monitor and control the gain of the photomultipliers so that the detector efficiency can be kept stable at a perce...

The LUCID-2 Detector

CERN Document Server

Pinfold, James; The ATLAS collaboration

2017-01-01

The LUCID-2 detector is the main online and offline luminosity provider of the ATLAS experiment. It provides over 100 different luminosity measurements from different algorithms for each of the 2808/3546 filled/total LHC bunches. LUCID was entirely redesigned in preparation for LHC Run 2: both the detector and the electronics were upgraded in order to cope with the challenging conditions expected at the LHC center of mass energy of 13 TeV with only 25 ns bunch-spacing. While LUCID-1 used gas as a Cherenkov medium, the LUCID-2 detector is in a new unique way using the quartz windows of small photomultipliers as the Cherenkov medium. The main challenge for a luminometer is to keep the efficiency constant during years of data-taking. LUCID-2 is using an innovative calibration system based on radioactive 207 Bi sources deposited on the quartz window of the readout photomultipliers. This makes it possible to accurately monitor and control the gain of the photomultipliers so that the detector efficiency can be kept...

The LUCID-2 detector

CERN Document Server

Sbarra, Carla; The ATLAS collaboration

2018-01-01

The LUCID-2 detector is the main online and offline luminosity provider of the ATLAS experiment. It provides over 100 different luminosity measurements from different algorithms for each of the 2808 LHC bunches. LUCID was entirely redesigned in preparation for LHC Run 2: both the detector and the electronics were upgraded in order to cope with the challenging conditions expected at the LHC center of mass energy of 13 TeV with only 25 ns bunch-spacing. While LUCID-1 used gas as a Cherenkov medium, the LUCID-2 detector is in a new unique way using the quartz windows of small photomultipliers as the Cherenkov medium. The main challenge for a luminometer is to keep the efficiency constant during years of data-taking. LUCID-2 is using an innovative calibration system based on radioactive 207 Bi sources deposited on the quartz window of the readout photomultipliers. This makes it possible to accurately monitor and control the gain of the photomultipliers so that the detector efficiency can be kept stable at a perce...

A novel design of a personal nuclear track detector for ambient Rn

International Nuclear Information System (INIS)

Margaliot, M.; Even, O.; Herman, R.

1997-01-01

In some occupations, workers spend a part of their time underground, in closed and unventilated spaces, while most of their time is spent in the open air. The case in hand is a group of the 'Bezek' telephone technicians, whose work includes spending a few hours daily in small, coarsely finished and unventilated tunnels in which telephone branching boxes are located. The rest of their time they work outdoors, and a small part of it is spent in offices. The Rn levels in a few telephone branching tunnels were measured and were found to be rather high (levels of 3000 - 5000 Bq/m 3 are common). The average exposure of the workers is however much lower, due to short time spent in the tunnels, versus the longer time spent outdoors, and the low Rn level there. To obtain a well founded estimation of their actual commutative Rn exposure, a new integrative Rn detector was designed, which is attached to the workers clothing during the whole working day, and serves as a personal Rn detector, rather than as the a conventional area monitor. The detector element itself consists of a Nuclear Track Detector made of dosimetry grade CR-39. The function of the detector is how ever dependent mainly on the geometrical design of the housing of the detector. The properties of these detectors are, however, highly dependent on the design of the detectors housing.The design itself, it's theoretical efficiency, it's actual calibration process and it's calibration factor are presented. Mechanical reliability has been established in some 3 years of operation both as a fixed area monitor and as a personal portable detector. (authors)

Photomultiplier tubes for Low Level Cerenkov Detectors

Energy Technology Data Exchange (ETDEWEB)

Strindehag, O

1965-03-15

Tube backgrounds of several 2-inch photomultiplier types having S11, 'S' , S13 and S20 cathodes are compared by measuring signal and background pulse height distributions at pulse heights corresponding to a few photo-electrons. The reference signal is generated by means of a {beta}-source and a plexiglass radiator. It is found that comparatively good results are obtained with selected tubes of the EMI types 6097B and 9514B having equivalent dark current dc values down to 10{sup -12} input lumens. Special interest is devoted to the correlation between the measured tube backgrounds and the dark current dc values of the tubes, as a good correlation between these parameters simplifies the selection of photomultiplier tubes. The equivalent dark currents of the tested tubes extend over the range 10{sup -12} to 10{sup -9} input lumens. Although the investigation deals with photomultiplier tubes intended for use in low level Cerenkov detectors it is believed that the results could be valuable in other fields where photomultiplier tubes are utilized for the detection of weak light pulses.

Photomultiplier tubes for Low Level Cerenkov Detectors

International Nuclear Information System (INIS)

Strindehag, O.

1965-03-01

Tube backgrounds of several 2-inch photomultiplier types having S11, 'S' , S13 and S20 cathodes are compared by measuring signal and background pulse height distributions at pulse heights corresponding to a few photo-electrons. The reference signal is generated by means of a β-source and a plexiglass radiator. It is found that comparatively good results are obtained with selected tubes of the EMI types 6097B and 9514B having equivalent dark current dc values down to 10 -12 input lumens. Special interest is devoted to the correlation between the measured tube backgrounds and the dark current dc values of the tubes, as a good correlation between these parameters simplifies the selection of photomultiplier tubes. The equivalent dark currents of the tested tubes extend over the range 10 -12 to 10 -9 input lumens. Although the investigation deals with photomultiplier tubes intended for use in low level Cerenkov detectors it is believed that the results could be valuable in other fields where photomultiplier tubes are utilized for the detection of weak light pulses

Proposed Hall D Detector Electronics

International Nuclear Information System (INIS)

Paul Smith

1998-01-01

With nearly 10**5 channels, the signal processing and data acquisition electronics system will present a significant challenge. We envisage much of the electronics being physically located on or near the detectors to avoid the long and expensive low-level signal cables otherwise required. CERN detectors such as COMPASS and ATLAS provide a good model, and we should build on their experience as much as possible. Radiation hardness and minimal power dissipation are additional constraints. The high beam rate will necessitate good time resolution, integrated low level triggering capability and sufficient pipelining of the data to accommodate the trigger decision time. A proposed architecture is shown in the figure. Detector channels are either ''pixels'', e.g. PWCs, drift chambers, and ring cerenkovs, or charge detectors, e.g. CSI or lead glass. Pixel detectors are discriminated, while charge detectors are digitized by Flash ADCs (FADC). The digitized information is pipelined in shift registers which provide a time window for the first level of triggering to consider. After passing through the shift registers, the data are further pipelined in RAM to provide time for the level 1 trigger decision. In the event of a level 1 trigger, the RAM contents are transferred to a level 2 processor farm where more detailed trigger decisions take place

Testing the Isotropic Universe Using the Gamma-Ray Burst Data of Fermi/GBM

Science.gov (United States)

Řípa, Jakub; Shafieloo, Arman

2017-12-01

The sky distribution of gamma-ray bursts (GRBs) has been intensively studied by various groups for more than two decades. Most of these studies test the isotropy of GRBs based on their sky number density distribution. In this work, we propose an approach to test the isotropy of the universe through inspecting the isotropy of the properties of GRBs such as their duration, fluences, and peak fluxes at various energy bands and different timescales. We apply this method on the Fermi/Gamma-ray Burst Monitor (GBM) data sample containing 1591 GRBs. The most noticeable feature we found is near the Galactic coordinates l≈ 30^\\circ , b≈ 15^\\circ , and radius r≈ 20^\\circ {--}40^\\circ . The inferred probability for the occurrence of such an anisotropic signal (in a random isotropic sample) is derived to be less than a percent in some of the tests while the other tests give results consistent with isotropy. These are based on the comparison of the results from the real data with the randomly shuffled data samples. Considering the large number of statistics we used in this work (some of which are correlated with each other), we can anticipate that the detected feature could be a result of statistical fluctuations. Moreover, we noticed a considerably low number of GRBs in this particular patch, which might be due to some instrumentation or observational effects that can consequently affect our statistics through some systematics. Further investigation is highly desirable in order to clarify this result, e.g., utilizing a larger future Fermi/GBM data sample as well as data samples of other GRB missions and also looking for possible systematics.

The AFP Detector Control System

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00514541; The ATLAS collaboration

2017-01-01

The ATLAS Forward Proton (AFP) detector is one of the forward detectors of the ATLAS experiment at CERN aiming at measuring momenta and angles of diffractively scattered protons. Silicon Tracking and Time-of-Flight detectors are located inside Roman Pot stations inserted into beam pipe aperture. The AFP detector is composed of two stations on each side of the ATLAS interaction point and is under commissioning. The detector is provided with high and low voltage distribution systems. Each station has vacuum and cooling systems, movement control and all the required electronics for signal processing. Monitoring of environmental parameters, like temperature and radiation, is also available. The Detector Control System (DCS) provides control and monitoring of the detector hardware and ensures the safe and reliable operation of the detector, assuring good data quality. Comparing with DCS systems of other detectors, the AFP DCS main challenge is to cope with the large variety of AFP equipment. This paper describes t...

The AFP detector control system

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00514541; The ATLAS collaboration; Caforio, Davide; Czekierda, Sabina; Hajduk, Zbigniew; Olszowska, Jolanta; Sicho, Petr; Zabinski, Bartlomiej

The ATLAS Forward Proton (AFP) detector is one of the forward detectors of the ATLAS experiment at CERN aiming at measuring momenta and angles of diffractively scattered protons. Silicon Tracking and Time-of-Flight detectors are located inside Roman Pot stations inserted into beam pipe aperture. The AFP detector is composed of two stations on each side of the ATLAS interaction point and is under commissioning. The detector is provided with high and low voltage distribution systems. Each station has vacuum and cooling systems, movement control and all the required electronics for signal processing. Monitoring of environmental parameters, like temperature and radiation, is also available. The Detector Control System (DCS) provides control and monitoring of the detector hardware and ensures the safe and reliable operation of the detector, assuring good data quality. Comparing with DCS systems of other detectors, the AFP DCS main challenge is to cope with the large variety of AFP equipment. This paper describes t...

Semiconductor detectors in nuclear and particle physics

International Nuclear Information System (INIS)

Rehak, P.; Gatti, E.

1992-01-01

Semiconductor detectors for elementary particle physics and nuclear physics in the energy range above 1 GeV are briefly reviewed. In these two fields semiconductor detectors are used mainly for the precise position sensing. In a typical experiment, the position of a fast charged particle crossing a relatively thin semiconductor detector is measured. The position resolution achievable by semiconductor detectors is compared with the resolution achievable by gas filled position sensing detectors. Semiconductor detectors are divided into two groups: Classical semiconductor diode detectors and semiconductor memory detectors. Principles of the signal formation and the signal read-out for both groups of detectors are described. New developments of silicon detectors of both groups are reported

A content addressable memory for use in CEBAF's CLAS detector level 2 triggering system

International Nuclear Information System (INIS)

Hodson, R.F.; Doughty, D.C. Jr.; Allgood, D.C.; Campbell, S.A.; Wilson, W.C.; Bickley, M.H.

1996-01-01

A collaboration of researchers from CEBAF, CNU and NASA is designing a 256-32 specialized Content Addressable Memory (CAM) for the level 2 triggering system in CEBAF's CLAS detector. These integrated circuits will find tracks and the momentum and angle of each track within 2 microseconds of an event. The custom CAM can operate as conventional memory, performing read and write operations, and can additionally perform independent byte compare operations across all words simultaneously. It is this compare feature which makes these CAMs attractive for identifying tracks passing through drift chambers by linking together segment number triplets within the CAM. Simulations have indicated that less than 16 k triplets need to be stored for each sector of the detector. This implies the level 2 triggering can be performed with 64 CAM chips per sector, or 384 total. Each data channel into a sector CAM array is buffered in a FIFO and is designed to handle aggregate data rates up to 750 Mbs for three channels (one channel/superlayer). The architecture of the level 2 trigger and details of the CAM chip design are discussed along with a performance report on our prototype CAMs

The ZEUS second level calorimeter trigger

International Nuclear Information System (INIS)

Jong, S.J. de.

1990-01-01

ZEUS is a detector for the HERA ep collider, consisting of several large components. The most important being the inner tracking detectors, which are positioned nearest to the interaction point, the calorimeter surrounding the inner tracking detectors and the muon detectors on the outside of the experimental setup. Each component will deliver a vast amount of information. In order to keep this information manageable, data is preprocessed and condensed per component and then combined to obtain the final global trigger result. The main subject of this thesis is the second level calorimeter trigger processor of the ZEUS detector. In order to be able to reject the unwanted events passing the first level, the topological event signature will have to be used at the second level. The most demanding task of the second level is the recognition of local energy depositions corresponding to isolated electrons and hadron jets. Also part of the work performed by the first level will be repeated with a higher level of accuracy. Additional information not available to the first level trigger will be processed and will be made available to the global second level trigger decision module. For the second level calorimeter trigger processor a special VME module, containing two transputers, has been developed. The second level calorimeter trigger algorithm described in this thesis was tested with simulated events, that were tracked through a computer simulation of the ZEUS detector. A part of this thesis is therefore devoted to the description of the various Monte Carlo models and the justification of the way in which they were used. (author). 132 refs.; 76 figs.; 18 tabs

Pulmonary arterial hypertension in children: diagnosis using ratio of main pulmonary artery to ascending aorta diameter as determined by multi-detector computed tomography.

Science.gov (United States)

Caro-Domínguez, Pablo; Compton, Gregory; Humpl, Tilman; Manson, David E

2016-09-01

The ratio of the transverse diameter of the main pulmonary artery (MPA) to ascending aorta as determined at multi-detector CT is a tool that can be used to assess the pulmonary arterial size in cases of pulmonary arterial hypertension in children. To establish a ratio of MPA to ascending aorta diameter using multi-detector CT imaging suggestive of pulmonary arterial hypertension in children. We hypothesize that a defined ratio of MPA to ascending aorta is identifiable on multi-detector CT and that higher ratios can be used to reliably diagnose the presence of pulmonary arterial hypertension in children. We calculated the multi-detector CT ratio of MPA to ascending aorta diameter in 44 children with documented pulmonary arterial hypertension by right heart catheterization and in 44 age- and gender-matched control children with no predisposing factors for pulmonary arterial hypertension. We compared this multi-detector-CT-determined ratio with the MPA pressure in the study group, as well as with the ratio of MPA to ascending aorta in the control group. A threshold ratio value was calculated to accurately identify children with pulmonary arterial hypertension. Children with documented primary pulmonary arterial hypertension have a significantly higher ratio of MPA to ascending aorta (1.46) than children without pulmonary arterial hypertension (1.11). A ratio of 1.3 carries a positive likelihood of 34 and a positive predictive value of 97% for the diagnosis of pulmonary arterial hypertension. The pulmonary arteries were larger in children with pulmonary arterial hypertension than in a control group of normal children. A CT-measured ratio of MPA to ascending aorta of 1.3 should raise the suspicion of pulmonary arterial hypertension in children.

Food and nutrition security trends and challenges in the Ganges Brahmaputra Meghna (GBM delta

Directory of Open Access Journals (Sweden)

Arnout van Soesbergen

2017-09-01

Full Text Available The population of the Ganges Brahmaputra Meghna (GBM delta is highly vulnerable to food insecurity and malnutrition due to the specific environmental, climatic and human development factors affecting agricultural production and fisheries. To better understand the impacts of climate and environmental change on food security and nutrition in this delta, this study combines spatially explicit data from the 2007 and 2011 Bangladesh Demographic and Health Survey (BDHS with a standard satellite remotely sensed vegetation greenness index (Normalised Difference Vegetation Index, NDVI, used as a proxy for rice production. The strength of association between NDVI and child nutrition in this tropical mega-delta were tested, showing correlations between two widely used indicators of child malnutrition; stunting and wasting, and deviations from a 10 year mean NDVI (anomalies for rice crop growing seasons – regarded as critical to individual children’s early lives. For children surveyed in 2007 we found that the likelihood of being stunted decreased with increased NDVI as a measure of food production. Similarly, for children surveyed in 2011, the likelihood of being wasted reduced with increased NDVI. However, regression results for stunting in 2011 and wasting in 2007 were not statistically significant. Our findings suggest that NDVI can be regarded as indicative of climatic variability and periods of low food production but is only partly successful as an indicator of climate related impacts on child nutrition in the GBM delta. Furthermore, our study highlights some of the uncertainties and challenges with linking environmental indicators such as the NDVI with household survey data across spatial and temporal scales.

Upgrade of the First Level Muon Trigger in the End-Cap New Small Wheel Region of the ATLAS Detector

International Nuclear Information System (INIS)

Munwes, Yonathan

2013-06-01

The luminosity levels foreseen at the LHC after the 2018 LHC upgrade will tighten the demands on the ATLAS first level muon trigger system. A finer muon selection will be required to cope with the increased background and to keep the trigger rate for 20 GeV/c pTmuons as before. The introduction of new detectors in the small wheel region of the end-cap muon spectrometer will allow to refine the current trigger selection, allowing to increase the rejection power for tracks not coming from the interaction point, thus to find candidate muon tracks within 1 mrad angular resolution and within the 500 ns available latency. The on-detector trigger logic will require a coincidence of eight layers of small thin gap chambers detector pads to determine the trigger regions-of-interest. The charge information from the detector strips of the selected regions-of-interest will be sent to the off-detector trigger logic, which will calculate the strip centroids and extrapolate the muon tracks. The muon tracks information will be finally sent to the end-cap sector logic, which will combine the big wheel and the new small wheel trigger data, and provide the trigger muon candidates to the ATLAS central trigger. (author)

Semiconductor detectors in nuclear and particle physics

International Nuclear Information System (INIS)

Rehak, P.; Gatti, E.

1995-01-01

Semiconductor detectors for elementary particle physics and nuclear physics in the energy range above 1 GeV are briefly reviewed. In these two fields semiconductor detectors are used mainly for the precise position sensing. In a typical experiment, the position of a fast charged particle crossing a relatively thin semiconductor detector is measured. The position resolution achievable by semiconductor detectors is compared with the resolution achievable by gas filled position sensing detectors. Semiconductor detectors are divided into two groups; (i) classical semiconductor diode detectors and (ii) semiconductor memory detectors. Principles of the signal formation and the signal read-out for both groups of detectors are described. New developments of silicon detectors of both groups are reported. copyright 1995 American Institute of Physics

A vertex detector for the International Linear Collider based on CMOS sensors

Energy Technology Data Exchange (ETDEWEB)

Besson, Auguste [Institut de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France)]. E-mail: abesson@in2p3.fr; Claus, Gilles [Institut de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Colledani, Claude [Institut de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Degerli, Yavuz [CEA Saclay, DAPNIA, Gif-sur-Yvette Cedex (France); Deptuch, Grzegorz [Institut de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Deveaux, Michael [Institut de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France) and GSI, Planckstrasse 1, Darmstadt 64291 (Germany); Dulinski, Wojciech [Institut de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Fourches, Nicolas [CEA Saclay, DAPNIA, Gif-sur-Yvette Cedex (France); Goffe, Mathieu [Institut de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Grandjean, Damien [Institut de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Guilloux, Fabrice [Institut de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Heini, Sebastien [Institut de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France)]|[GSI, Planckstrasse 1, Darmstadt 64291 (Germany); Himmi, Abdelkader; Hu, Christine; Jaaskelainen, Kimmo [Institut de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Li, Yan; Lutz, Pierre; Orsini, Fabienne [CEA Saclay, DAPNIA, Gif-sur-Yvette Cedex (France); Pellicioli, Michel; Scopelliti, Emanuele; Shabetai, Alexandre; Szelezniak, Michal; Valin, Isabelle [Institut de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Winter, Marc [Institut de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France)]. E-mail: marc.winter@ires.in2p3.f

2006-11-30

The physics programme at the International Linear Collider (ILC) calls for a vertex detector (VD) providing unprecedented flavour tagging performances, especially for c-quarks and {tau} leptons. This requirement makes a very granular, thin and multi-layer VD installed very close to the interaction region mandatory. Additional constraints, mainly on read-out speed and radiation tolerance, originate from the beam background, which governs the occupancy and the radiation level the detector should be able to cope with. CMOS sensors are being developed to fulfil these requirements. This report addresses the ILC requirements (highly related to beamstrahlung), the main advantages and features of CMOS sensors, the demonstrated performances and the specific aspects of a VD based on this technology. The status of the main R and D directions (radiation tolerance, thinning procedure and read-out speed) are also presented.

Spectral evolution of GRBs with negative spectral lag using Fermi GBM observations

Science.gov (United States)

Chakrabarti, Arundhati; Chaudhury, Kishor; Sarkar, Samir K.; Bhadra, Arunava

2018-06-01

The positive spectral lag of Gamma Ray Bursts (GRBs) is often explained in terms of hard-to-soft spectral evolution of GRB pulses. While positive lags of GRBs is very common, there are few GRB pulses that exhibits negative spectral lags. In the present work we examine whether negative lags of GRBs also can be interpreted in terms of spectral evolution of GRB pulses or not. Using Fermi-GBM data, we identify two GRBs, GRB 090426C and GRB 150213A, with clean pulses that exhibit negative spectral lag. An indication of soft to hard transition has been noticed for the negative spectral lag events from the spectral evolution study. The implication of the present findings on the models of GRB spectral lags are discussed.

CXCL12 MODULATION OF CXCR4 AND CXCR7 ACTIVITY IN HUMAN GLIOBLASTOMA STEM-LIKE CELLS AND REGULATION OF THE TUMOR MICROENVIRONMENT

Directory of Open Access Journals (Sweden)

Roberto eWurth

2014-05-01

Full Text Available Chemokines are crucial autocrine and paracrine players in tumor development. In particular, CXCL12, through its receptors CXCR4 and CXCR7, affects tumor progression by controlling cancer cell survival, proliferation and migration, and, indirectly, via angiogenesis or recruiting immune cells.Glioblastoma (GBM is the most prevalent primary malignant brain tumor in adults and despite current multimodal therapies it remains almost incurable. The aggressive and recurrent phenotype of GBM is ascribed to high growth rate, invasiveness to normal brain, marked angiogenesis, ability to escape the immune system and resistance to standard of care therapies. Tumor molecular and cellular heterogeneity severely hinders GBM therapeutic improvement. In particular, a subpopulation of chemo- and radio-therapy resistant tumorigenic cancer stem–like cells (CSCs is believed to be the main responsible for tumor cell dissemination to the brain.GBM cells display heterogeneous expression levels of CXCR4 and CXCR7 that are overexpressed in CSCs, representing a molecular correlate for the invasive potential of GBM. The microenvironment contribution in GBM development is increasingly emphasized. An interplay exists between CSCs, differentiated GBM cells, and the microenvironment, mainly through secreted chemokines (e.g. CXCL12 causing recruitment of fibroblasts, endothelial, mesenchymal and inflammatory cells to the tumor, via specific receptors such as CXCR4.This review covers recent developments on the role of CXCL12/CXCR4-CXCR7 networks in GBM progression and the potential translational impact of their targeting. The biological and molecular understanding of the heterogeneous GBM cell behavior, phenotype and signaling is still limited. Progress in the identification of chemokine-dependent mechanisms that affect GBM cell survival, trafficking and chemo-attractive functions, opens new perspectives for development of more specific therapeutic approaches that include

Fold distributions at clover, crystal and segment levels for segmented clover detectors

International Nuclear Information System (INIS)

Kshetri, R; Bhattacharya, P

2014-01-01

Fold distributions at clover, crystal and segment levels have been extracted for an array of segmented clover detectors for various gamma energies. A simple analysis of the results based on a model independant approach has been presented. For the first time, the clover fold distribution of an array and associated array addback factor have been extracted. We have calculated the percentages of the number of crystals and segments that fire for a full energy peak event

An analytical model for a low-level uranium detector for soil analysis

International Nuclear Information System (INIS)

Fortkamp, J.C.

1994-01-01

This thesis addresses the need for a field useable means of measuring the concentration of 238 U in soil. An analytical model was developed and refined based on a method conceived by David Holcomb. The method utilizes the high energy β of 234m Pa, a daughter in secular equilibrium with 238 U. A subtraction of the contribution of any other high energy β emitters present is done using a gamma coincidence system. The main component of the detector system defined was a 30cmx60cmx0.2cm plastic scintillating sheet. It was also shown that with proper calibration, the subtraction process will give accurate measurements of the 238 U concentration

Instrumentation of a Level-1 Track Trigger in the ATLAS detector for the High Luminosity LHC

CERN Document Server

Boisvert, V; The ATLAS collaboration

2012-01-01

The Large Hadron Collider will be upgraded in order to reach an instantaneous luminosity of $L=5 \\times 10^{34}$ cm$^{-2}$ s$^{-1}$. A challenge for the detectors will be to cope with the excessive rate of events coming into the trigger system. In order to maintain the capability of triggering on single lepton objects with momentum thresholds of $p_T 25$ GeV, the ATLAS detector is planning to use tracking information at the Level-1 (hardware) stage of the trigger system. Two options are currently being studied: a L0/L1 trigger design using a double buffer front-end architecture and a single hardware trigger level which uses trigger layers in the new tracker system. Both options are presented as well as results from simulation studies.

Detectors - Electronics

International Nuclear Information System (INIS)

Bregeault, J.; Gabriel, J.L.; Hierle, G.; Lebotlan, P.; Leconte, A.; Lelandais, J.; Mosrin, P.; Munsch, P.; Saur, H.; Tillier, J.

1998-01-01

The reports presents the main results obtained in the fields of radiation detectors and associated electronics. In the domain of X-ray gas detectors for the keV range efforts were undertaken to rise the detector efficiency. Multiple gap parallel plate chambers of different types as well as different types of X → e - converters were tested to improve the efficiency (values of 2.4% at 60 KeV were reached). In the field of scintillators a study of new crystals has been carried out (among which Lutetium orthosilicate). CdTe diode strips for obtaining X-ray imaging were studied. The complete study of a linear array of 8 CdTe pixels has been performed and certified. The results are encouraging and point to this method as a satisfying solution. Also, a large dimension programmable chamber was used to study the influence of temperature on the inorganic scintillators in an interval from -40 deg. C to +150 deg. C. Temperature effects on other detectors and electronic circuits were also investigated. In the report mentioned is also the work carried out for the realization of the DEMON neutron multidetector. For neutron halo experiments different large area Si detectors associated with solid and gas position detectors were realized. In the frame of a contract with COGEMA a systematic study of Li doped glasses was undertaken aiming at replacing with a neutron probe the 3 He counters presently utilized in pollution monitoring. An industrial prototype has been realised. Other studies were related to integrated analog chains, materials for Cherenkov detectors, scintillation probes for experiments on fundamental processes, gas position sensitive detectors, etc. In the field of associated electronics there are mentioned the works related to the multidetector INDRA, data acquisition, software gamma spectrometry, automatic gas pressure regulation in detectors, etc

Effect of weatherization on radon levels in Maine dwellings

International Nuclear Information System (INIS)

Hess, C.T.; Hill, R.C.

1984-01-01

A study of radon concentration in the air of 30 Maine dwellings was performed before and after weatherization during November 1982-May 1983. The average radon (.75 pCi/1) was lower than a group of houses in a previous study in October 1980-May 1981 (3.1 pCi/1). The after-weatherization levels show an increase over the before-weatherization levels. Trailers were found to have lower radon concentrations than houses. The maximum value measured was 3.2 pCi/1 before and 6.2 pCi/1 after correction for season of exposure. 13 references, 5 figures, 3 tables

Application of neutron backscatter techniques to level measurement problems

International Nuclear Information System (INIS)

Leonardi-Cattolica, A.M.; McMillan, D.H.; Telfer, A.; Griffin, L.H.; Hunt, R.H.

1982-01-01

We have designed and built portable level detectors and fixed level monitors based on neutron scattering and detection principles. The main components of these devices, which we call neutron backscatter gauges, are a neutron emitting radioisotope, a neutron detector, and a ratemeter. The gauge is a good detector for hydrogen but is much less sensitive to most other materials. This allows level measurements of hydrogen bearing materials, such as hydrocarbons, to be made through the walls of metal vessels. Measurements can be made conveniently through steel walls which are a few inches thick. We have used neutron backscatter gauges in a wide variety of level measurement applications encountered in the petrochemical industry. In a number of cases, the neutron techniques have proven to be superior to conventional level measurement methods, including gamma ray methods

Detector for failed fuel elements

International Nuclear Information System (INIS)

Ito, Masaru.

1979-01-01

Purpose: To provide automatic monitor for the separation or reactor water and sampling water, in a failed fuel element detector using a sipping chamber. Constitution: A positional detector for the exact mounting of a sipping chamber on a channel box and a level detector for the detection of complete discharge of cooling water in the sipping chamber are provided in the sipping chamber. The positional detector is contacted to the upper end of the channel box and operated when the sipping chamber is correctly mounted to the fuel assemblies. The level detector comprises a float and a limit switch and it is operated when the water in the sipping chamber is discharged by a predetermined amount. Isolation of reactor water and sampling water are automatically monitored by the signal from these two detectors. (Ikeda, J.)

In-core monitoring detectors

International Nuclear Information System (INIS)

Mitelman, M.G.

2001-01-01

The main task of in-core monitoring consists in securing observability of the reactor installation in all possible operation modes (normal, transient, accident and post-accident). Operation safety at acceptable cost can be achieved by optimized measurement errors. The range of sensors applied as in-core detectors for operative measurements in the industry is very limited in number. Among them might be cited self powered neutron detectors (SPND) and thermocouples. Sensors are incorporated in the in-core detectors assemblies (SVRD). The presentation makes an effort to touch upon the problems of assuring and increasing quality of in-core on-line measurements. So we do not consider systems using movable detectors, as the latter do not assure on-line measurements. (Authors)

Pulmonary arterial hypertension in children: diagnosis using ratio of main pulmonary artery to ascending aorta diameter as determined by multi-detector computed tomography

International Nuclear Information System (INIS)

Caro-Dominguez, Pablo; Manson, David E.; Compton, Gregory; Humpl, Tilman

2016-01-01

The ratio of the transverse diameter of the main pulmonary artery (MPA) to ascending aorta as determined at multi-detector CT is a tool that can be used to assess the pulmonary arterial size in cases of pulmonary arterial hypertension in children. To establish a ratio of MPA to ascending aorta diameter using multi-detector CT imaging suggestive of pulmonary arterial hypertension in children. We hypothesize that a defined ratio of MPA to ascending aorta is identifiable on multi-detector CT and that higher ratios can be used to reliably diagnose the presence of pulmonary arterial hypertension in children. We calculated the multi-detector CT ratio of MPA to ascending aorta diameter in 44 children with documented pulmonary arterial hypertension by right heart catheterization and in 44 age- and gender-matched control children with no predisposing factors for pulmonary arterial hypertension. We compared this multi-detector-CT-determined ratio with the MPA pressure in the study group, as well as with the ratio of MPA to ascending aorta in the control group. A threshold ratio value was calculated to accurately identify children with pulmonary arterial hypertension. Children with documented primary pulmonary arterial hypertension have a significantly higher ratio of MPA to ascending aorta (1.46) than children without pulmonary arterial hypertension (1.11). A ratio of 1.3 carries a positive likelihood of 34 and a positive predictive value of 97% for the diagnosis of pulmonary arterial hypertension. The pulmonary arteries were larger in children with pulmonary arterial hypertension than in a control group of normal children. A CT-measured ratio of MPA to ascending aorta of 1.3 should raise the suspicion of pulmonary arterial hypertension in children. (orig.)

Pulmonary arterial hypertension in children: diagnosis using ratio of main pulmonary artery to ascending aorta diameter as determined by multi-detector computed tomography

Energy Technology Data Exchange (ETDEWEB)

Caro-Dominguez, Pablo; Manson, David E. [University of Toronto, Department of Diagnostic Imaging, The Hospital for Sick Children, Department of Medical Imaging, Toronto, ON (Canada); Compton, Gregory [University of Toronto, Department of Diagnostic Imaging, The Hospital for Sick Children, Department of Medical Imaging, Toronto, ON (Canada); Epworth Hospital, Epworth Medical Imaging, Richmond, VIC (Australia); Humpl, Tilman [University of Toronto, Division of Cardiology, Department of Pediatrics, The Hospital for Sick Children, Toronto, ON (Canada)

2016-09-15

The ratio of the transverse diameter of the main pulmonary artery (MPA) to ascending aorta as determined at multi-detector CT is a tool that can be used to assess the pulmonary arterial size in cases of pulmonary arterial hypertension in children. To establish a ratio of MPA to ascending aorta diameter using multi-detector CT imaging suggestive of pulmonary arterial hypertension in children. We hypothesize that a defined ratio of MPA to ascending aorta is identifiable on multi-detector CT and that higher ratios can be used to reliably diagnose the presence of pulmonary arterial hypertension in children. We calculated the multi-detector CT ratio of MPA to ascending aorta diameter in 44 children with documented pulmonary arterial hypertension by right heart catheterization and in 44 age- and gender-matched control children with no predisposing factors for pulmonary arterial hypertension. We compared this multi-detector-CT-determined ratio with the MPA pressure in the study group, as well as with the ratio of MPA to ascending aorta in the control group. A threshold ratio value was calculated to accurately identify children with pulmonary arterial hypertension. Children with documented primary pulmonary arterial hypertension have a significantly higher ratio of MPA to ascending aorta (1.46) than children without pulmonary arterial hypertension (1.11). A ratio of 1.3 carries a positive likelihood of 34 and a positive predictive value of 97% for the diagnosis of pulmonary arterial hypertension. The pulmonary arteries were larger in children with pulmonary arterial hypertension than in a control group of normal children. A CT-measured ratio of MPA to ascending aorta of 1.3 should raise the suspicion of pulmonary arterial hypertension in children. (orig.)

Measurement of integrated flux of cosmic ray muons at sea level using the INO-ICAL prototype detector

International Nuclear Information System (INIS)

Pal, S.; Acharya, B.S.; Majumder, G.; Mondal, N.K.; Samuel, D.; Satyanarayana, B.

2012-01-01

The India-based Neutrino Observatory (INO) collaboration is planning to set-up a magnetized Iron-CALorimeter (ICAL) to study atmospheric neutrino oscillations with precise measurements of oscillations parameters. The ICAL uses 50 kton iron as target mass and about 28800 Resistive Plate Chambers (RPC) of 2 m × 2 m in area as active detector elements. As part of its R and D program, a prototype detector stack comprising 12 layers of RPCs of 1 m × 1 m in area has been set-up at Tata Institute of Fundamental Research (TIFR) to study the detector parameters using cosmic ray muons. We present here a study of muon flux measurement at sea level and lower latitude. (Site latitude: 18°54'N, longitude: 72°48'E.)

Intracellular cholesterol level regulates sensitivity of glioblastoma cells against temozolomide-induced cell death by modulation of caspase-8 activation via death receptor 5-accumulation and activation in the plasma membrane lipid raft.

Science.gov (United States)

Yamamoto, Yutaro; Tomiyama, Arata; Sasaki, Nobuyoshi; Yamaguchi, Hideki; Shirakihara, Takuya; Nakashima, Katsuhiko; Kumagai, Kosuke; Takeuchi, Satoru; Toyooka, Terushige; Otani, Naoki; Wada, Kojiro; Narita, Yoshitaka; Ichimura, Koichi; Sakai, Ryuichi; Namba, Hiroki; Mori, Kentaro

2018-01-01

Development of resistance against temozolomide (TMZ) in glioblastoma (GBM) after continuous treatment with TMZ is one of the critical problems in clinical GBM therapy. Intracellular cholesterol regulates cancer cell biology, but whether intracellular cholesterol is involved in TMZ resistance of GBM cells remains unclear. The involvement of intracellular cholesterol in acquired resistance against TMZ in GBM cells was investigated. Intracellular cholesterol levels were measured in human U251 MG cells with acquired TMZ resistance (U251-R cells) and TMZ-sensitive control U251 MG cells (U251-Con cells), and found that the intracellular cholesterol level was significantly lower in U251-R cells than in U251-Con cells. In addition, treatment by intracellular cholesterol remover, methyl-beta cyclodextrin (MβCD), or intracellular cholesterol inducer, soluble cholesterol (Chol), regulated TMZ-induced U251-Con cell death in line with changes in intracellular cholesterol level. Involvement of death receptor 5 (DR5), a death receptor localized in the plasma membrane, was evaluated. TMZ without or with MβCD and/or Chol caused accumulation of DR5 into the plasma membrane lipid raft and formed a complex with caspase-8, an extrinsic caspase cascade inducer, reflected in the induction of cell death. In addition, treatment with caspase-8 inhibitor or knockdown of DR5 dramatically suppressed U251-Con cell death induced by combination treatment with TMZ, MβCD, and Chol. Combined treatment of Chol with TMZ reversed the TMZ resistance of U251-R cells and another GBM cell model with acquired TMZ resistance, whereas clinical antihypercholesterolemia agents at physiological concentrations suppressed TMZ-induced cell death of U251-Con cells. These findings suggest that intracellular cholesterol level affects TMZ treatment of GBM mediated via a DR5-caspase-8 mechanism. Copyright © 2017 Elsevier Inc. All rights reserved.

The D0 detector upgrade

International Nuclear Information System (INIS)

Bross, A.D.

1995-02-01

The Fermilab collider program is undergoing a major upgrade of both the accelerator complex and the two detectors. Operation of the Tevatron at luminosities upwards of ten time that currently provided will occur in early 1999 after the commissioning of the new Fermilab Main Injector. The D0 upgrade program has been established to deliver a detector that will meet the challenges of this environment. A new magnetic tracker consisting of a superconducting solenoid, a silicon vertex detector, a scintillating fiber central tracker, and a central preshower detector will replace the current central tracking and transition radiation chambers. We present the design and performance capabilities of these new systems and describe results from physics simulations that demonstrate the physics reach of the upgraded detector

Physics and Detectors at CLIC

CERN Multimedia

CERN. Geneva

2012-01-01

CLIC represents an attractive option for the future particle physics programme at the energy frontier. CLIC is a proposed electron-positron linear collider, based on a novel two beam accelerating structure, with the capability of operating at centre-of-mass energies of up to 3 TeV. The Physics and Detector volume of the CLIC conceptual design report was recently published as a CERN yellow report. In this seminar, I will review the conclusions of this report, focussing on four main areas. Firstly, I will give an overview of the physics potential at CLIC, and will place this in the context of a possible scenario for the staged construction of the machine. Secondly, I will discuss the challenges for a detector operating in the CLIC machine environment. I will then present detailed studies of possible detector concepts, based on high granularity particle flow calorimetry, which demonstrate that the required detector performance goals at CLIC can be met. Finally, I will highlight the main issues for the future R&a...

The data acquisition system of the Belle II Pixel Detector

Science.gov (United States)

Münchow, D.; Dingfelder, J.; Geßler, T.; Konorov, I.; Kühn, W.; Lange, S.; Lautenbach, K.; Levit, D.; Liu, Z.; Marinas, C.; Schnell, M.; Spruck, B.; Zhao, J.

2014-08-01

At the future Belle II experiment the DEPFET (DEPleted Field Effect Transistor) pixel detector will consist of about 8 million channels and is placed as the innermost detector. Because of its small distance to the interaction region and the high luminosity in Belle II, for a trigger rate of about 30 kHz with an estimated occupancy of about 3 % a data rate of about 22 GB/s is expected. Due to the high data rate, a data reduction factor higher than 30 is needed in order to stay inside the specifications of the event builder. The main hardware to reduce the data rate is a xTCA based Compute Node (CN) developed in cooperation between IHEP Beijing and University Giessen. Each node has as main component a Xilinx Virtex-5 FX70T FPGA and is equipped with 2 × 2 GB RAM , GBit Ethernet and 4 × 6.25 Gb/s optical links. An ATCA carrier board is able to hold up to four CN and supplies high bandwidth connections between the four CNs and to the ATCA backplane. To achieve the required data reduction on the CNs, regions of interest (ROI) are used. These regions are calculated in two independent systems by projecting tracks back to the pixel detector. One is the High Level Trigger (HLT) which uses data from the Silicon Vertex Detector (SVD), a silicon strip detector, and outer detectors. The other is the Data Concentrator (DATCON) which calculates ROIs based on SVD data only, in order to get low momentum tracks. With this information, only PXD data inside these ROIs will be forwarded to the event builder, while data outside of these regions will be discarded. First results of the test beam time in January 2014 at DESY with a Belle II vertex detector prototype and full DAQ chain will be presented.

The MINERνA detector

Energy Technology Data Exchange (ETDEWEB)

Fiorentini, G. A. [Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro, RJ (Brazil)

2015-05-15

MINERνA (Main INjector Experiment for ν-A) is a dedicated neutrino-nucleus scattering experiment at Fermilab. It uses a fine-grained fully active detector to make precision measurements of neutrino and antineutrino interactions on a variety of different nuclear targets (plastic scintillator, C, Fe, Pb, He and H2O) for energies up to few GeV. An overview of the experiment and a description of the detector are presented.

Dosimetry in radiotherapy with natural diamond detectors

International Nuclear Information System (INIS)

De Angelis, C.; Onori, S.; Pacilio, M.; Cirrone, G.A.P.; Cuttone, G.; Raffaele, L.; Bucciolini, M.; Mazzocchi, S.

2002-01-01

There is wide interest in the use of diamond detectors for dosimetry in radiotherapy mainly because of the small dimensions, radiation hardness, nearly tissue equivalence of sensitive material and capability to deliver the dosimetric response 'on line'. In order to assess the dosimetric properties of PTW Riga diamond detectors type 60003, experiments were performed in conventional (high energy photon and electron) therapy beams as well as in proton therapy beams. The main detector features investigated were reproducibility of response, dose-signal relationship, temperature dependence, dose-rate dependence, energy dependence and angular dependence. High energy photons (6-25 MV) and electrons (6-22 MeV), available at the Radiotherapy Department of the Florence University, were used for investigating the general properties. Two different PTW diamond detectors of the same type were used to evidence inter-sample differences. The beam quality dependence of the detector response is probably the most critical point and this statement is of particular relevance for proton dosimetry since the proton LET changes with depth in the medium. Mainly because of the little information available on detector sensitivity variations with beam energy, the use of diamonds for clinical proton dosimetry is not widespread. In two recent papers a sensitivity dependence on proton energy of a natural PTW diamond detector has been reported. Due to the necessity to characterise each diamond detector individually the PTW Riga natural diamond detector in operation at the LNS-INFN, Catania, Italy was tested with the local proton beam line. This experiment is of main concern because this proton beam, produced by a superconducting cyclotron and used for ocular melanoma treatment, is available only since 2001 (CATANA beam). The first patient has been treated in February 2002. Proton irradiations were performed with non modulated and modulated 62 MeV beams. Attention was focused on diamond sensitivity

Electret radiation detector

International Nuclear Information System (INIS)

Kubu, M.

1981-01-01

The electret radiation detector consists of 30 to 35% of bee wax and of 65 to 70% of colophony. It is mainly the induction conductivity of charo.es between the dipoles in the electret which is used for detection. In the manufacture of the detector, the average atomic number of the electret can be altered by adding various compounds, such as ZnO, which also increases efficiency for gamma radiation. An alpha or beta emitter can also be built-in in the electret. (B.S.)

Two-Level Designs to Estimate All Main Effects and Two-Factor Interactions

NARCIS (Netherlands)

Eendebak, P.T.; Schoen, E.D.

2017-01-01

We study the design of two-level experiments with N runs and n factors large enough to estimate the interaction model, which contains all the main effects and all the two-factor interactions. Yet, an effect hierarchy assumption suggests that main effect estimation should be given more prominence

Monte-Carlo background simulations of present and future detectors in x-ray astronomy

Science.gov (United States)

Tenzer, C.; Kendziorra, E.; Santangelo, A.

2008-07-01

Reaching a low-level and well understood internal instrumental background is crucial for the scientific performance of an X-ray detector and, therefore, a main objective of the instrument designers. Monte-Carlo simulations of the physics processes and interactions taking place in a space-based X-ray detector as a result of its orbital environment can be applied to explain the measured background of existing missions. They are thus an excellent tool to predict and optimize the background of future observatories. Weak points of a design and the main sources of the background can be identified and methods to reduce them can be implemented and studied within the simulations. Using the Geant4 Monte-Carlo toolkit, we have created a simulation environment for space-based detectors and we present results of such background simulations for XMM-Newton's EPIC pn-CCD camera. The environment is also currently used to estimate and optimize the background of the future instruments Simbol-X and eRosita.

The international linear collider. Technical design report. Vol. 4. Detectors

Energy Technology Data Exchange (ETDEWEB)

Behnke, Ties; Brau, James E.; Burrows, Philip; Fuster, Juan; Peskin, Michael; Stanitzki, Marcel; Sugimoto, Yasuhiro; Yamada, Sakue; Yamamoto, Hitoshi [eds.

2013-10-01

The following topics are dealt with: The Si Vertex detectors, the main tracker, calorimetry, muon detectors, the superconducting spectrometer magnet, the detector electronics and data acquisition, simulation and reconstruction, benchmarking, costs. (HSI)

The international linear collider. Technical design report. Vol. 4. Detectors

International Nuclear Information System (INIS)

Behnke, Ties; Brau, James E.; Burrows, Philip; Fuster, Juan; Peskin, Michael; Stanitzki, Marcel; Sugimoto, Yasuhiro; Yamada, Sakue; Yamamoto, Hitoshi

2013-01-01

The following topics are dealt with: The Si Vertex detectors, the main tracker, calorimetry, muon detectors, the superconducting spectrometer magnet, the detector electronics and data acquisition, simulation and reconstruction, benchmarking, costs. (HSI)

The IPV-GBM scale: a new scale to measure intimate partner violence among gay and bisexual men.

Science.gov (United States)

Stephenson, Rob; Finneran, Catherine

2013-01-01

The paper describes the creation of a new scale to measure intimate partner violence (IPV) among gay and bisexual men. Seven focus group discussions were held with gay and bisexual men, focusing on defining intimate partner violence: 30 forms of IPV were identified. A venue-recruited sample of 912 gay and bisexual men was surveyed, examining definitional understanding and recent experiences of each of the 30 forms of IPV. Participants were also asked questions from the CDC definition of intimate partner violence and the short-form of the Conflicts Tactics Scale (CTS2S). Factor analysis of responses to the definitional questions was used to create the IPV-GBM scale, and the prevalence of intimate partner violence was compared with that identified by the CDC and CTS2S measures of intimate partner violence. A 23-item scale, with 5 unique domains, was created, with strong internal reliability (Cronbach Alpha >.90). The IPV-GBM scale mirrored both the CDC and CTS2S definitions of intimate partner violence, but contained additional domains such as controlling violence, monitoring behaviors, emotional violence, and HIV-related violence. The new scale identified a significantly higher prevalence of IPV than either of the more commonly used measures. The results presented here provide encouraging evidence for a new, more accurate measure of intimate partner violence among gay and bisexual men in the U.S.

The IPV-GBM scale: a new scale to measure intimate partner violence among gay and bisexual men.

Directory of Open Access Journals (Sweden)

Rob Stephenson

Full Text Available The paper describes the creation of a new scale to measure intimate partner violence (IPV among gay and bisexual men.Seven focus group discussions were held with gay and bisexual men, focusing on defining intimate partner violence: 30 forms of IPV were identified. A venue-recruited sample of 912 gay and bisexual men was surveyed, examining definitional understanding and recent experiences of each of the 30 forms of IPV. Participants were also asked questions from the CDC definition of intimate partner violence and the short-form of the Conflicts Tactics Scale (CTS2S. Factor analysis of responses to the definitional questions was used to create the IPV-GBM scale, and the prevalence of intimate partner violence was compared with that identified by the CDC and CTS2S measures of intimate partner violence.A 23-item scale, with 5 unique domains, was created, with strong internal reliability (Cronbach Alpha >.90. The IPV-GBM scale mirrored both the CDC and CTS2S definitions of intimate partner violence, but contained additional domains such as controlling violence, monitoring behaviors, emotional violence, and HIV-related violence. The new scale identified a significantly higher prevalence of IPV than either of the more commonly used measures.The results presented here provide encouraging evidence for a new, more accurate measure of intimate partner violence among gay and bisexual men in the U.S.

Cryogenic detectors for particle physics

International Nuclear Information System (INIS)

Gonzalez-Mestres, L.; Perret-Gallix, D.

1988-11-01

A comprehensive introduction to cryogenic detector developments for particle physics is presented, covering conventional detectors cooled to low temperature (scintillators and semiconductors), superconductive and thermal sensitive devices, as well as the basics of cold electronics. After giving a critical overview of current work, we elaborate on possible new ways for further improvements and briefly evaluate the feasibility of the main proposed applications

Radiation detectors laboratory

International Nuclear Information System (INIS)

Ramirez J, F.J.

1996-01-01

The National Institute for Nuclear Research has established a Radiation detector laboratory that has the possibility of providing to the consultants on the handling and applications of the nuclear radiation detectors. It has special equipment to repair the radiation detectors used in spectroscopy as the hyper pure Germanium for gamma radiation and the Lithium-silica for X-rays. There are different facilities in the laboratory that can become useful for other institutions that use radiation detectors. This laboratory was created to satisfy consultant services, training and repairing of the radiation detectors both in national and regional levels for Latin America. The laboratory has the following sections: Nuclear Electronic Instrumentation; where there are all kind of instruments for the measurement and characterization of detectors like multichannel analyzers of pulse height, personal computers, amplifiers and nuclear pulse preamplifiers, nuclear pulses generator, aleatories, computer programs for radiation spectra analysis, etc. High vacuum; there is a vacuum escape measurer, two high vacuum pumps to restore the vacuum of detectors, so the corresponding measurers and the necessary tools. Detectors cleaning; there is an anaerobic chamber for the detectors handling at inert atmosphere, a smoke extraction bell for cleaning with the detector solvents. Cryogenic; there are vessels and tools for handling liquid nitrogen which is used for cooling the detectors when they required it. (Author)

Spectral and spatial resolution properties of photon counting X-ray detectors like the Medipix-Detector

International Nuclear Information System (INIS)

Korn, A.

2007-01-01

The Medipix detector is a hybrid photon counting X-ray detector, consisting of an ASIC and a semiconducting layer as the sensor. This makes the Medipix a direct converting detector. A special feature of the Medipix is a signal processing circuit in every single pixel. This circuit amplifies the input signal triggered by a photon and then transforms the pulse into a digital signal. This early stage digitalisation is one of the main advantages of the detector, since no dark currents are integrated into the signal. Furthermore, the energy information of each single photon is partly preserved. The high number of pixels lends the detector a wide dynamic range, starting from single counts up to a rate of 1010 photons per cm2 and second. Apart from the many advantages, there are still some problems with the detector. Some effects lead to a deterioration of the energy resolution as well as the spatial resolution. The main reasons for this are two effects occuring in the detector, charge sharing and backscattering inside the detector. This study investigates the influence of those two effects on both the energy and spatial resolution. The physical causes of these effects are delineated and their impact on the detector output is examined. In contrast to high energy photon detectors, the repulsion of the charge carriers drifting inside the sensor must not be neglected in a detailed model of X-ray detectors with an energy range of 5 keV-200 keV. For the simulation of the Medipix using Monte Carlo simulations, the software ROSI was augmented. The added features allow a detailed simulation of the charge distribution, using the relevant physical effects that alter the distribution width during the drift towards the sensor electrodes as well further influences on the detector output, including electronical noise, threshold noise or the geometry of the detector. The measured energy and spatial resolution of several different models of Medipix is compared to the simulated

Clinical dosimeter based on diamond detector

International Nuclear Information System (INIS)

Chervjakov, A.M.; Ljalina, L.I.; Ljutina, G.J.; Khrunov, V.S.; Martynov, S.S.; Popov, S.A.

2002-01-01

Full text: Diamond detectors have found application in the relative dosimetry and their parameters have been described elsewhere. Today, the exclusive producer of the diamond detector is the Institute of Physical and Technical Problems, Russia, and exclusive dealer is the PTW-Freiburg. The main features of the diamond detector are good long time stability, suitable range of the energy dependence for photon and electron beams in clinical use, independence of the measured date from temperature and pressure. The high sensitivity per volume unit of the diamond detector (1500 times higher than ionization chamber) allowed using detectors with very small volume (1-5 mm 3 ) and rather simple electronics for ionization current registration. The new dosimeter consists of the diamond detector itself, 40 m registration cable, pre-amplifier, micro-processor block for data handling and absorbed dose calculation using the calibration factor of diamond detector in terms of absorbed dose to water. Dosimeter has the possibility to work with PC using standard RS-232 interface. The main features of the dosimeter are as follows: the range of dose rate measurements for photon, electron and proton beams is within 0.01-1.0 Gy/s; the energy ranges for photons are 0.08-25 MeV, and 4-25 MeV for electrons, with energy dependence no more than ±2%; the main uncertainty of the dose measurements is within ±2%; the pre-irradiation dose for diamond detector is no more than 10 Gy; the sensitive volume of the used diamond detectors is within 1-5 mm 3 ; the weight of the dosimeter no more than 2 kg. The new dosimeter was evaluated at the Central Research Institute of Roentgenology and Radiology, St. Petersburg, Russia to verify its performance. The dosimeter was used as a reference instrument for dose measurements at Cobalt-60 unit, SL75-5 and SL-20 linear accelerators and the test results have shown that the device have met the specifications. It is planned to produce dosimeter as serial device by

Accurate and independent spectral response scale based on silicon trap detectors and spectrally invariant detectors

International Nuclear Information System (INIS)

Gran, Jarle

2005-01-01

of the trap detector is very close to the responisivity of an ideal detector over most of its spectral range. The uncertainties given in (b) are very low uncertainties for the spectral response scales in the visual and infrared. The improvements of using the hybrid self calibration method is clearly demonstrated, though longer integration time and more measurement series in the purely relative method is expected to reduce the uncertainty in that method as well. The suggested methods presented in this thesis would improve if better spectrally invariant detectors were developed. Designing spectrally invariant detectors to be chilled with liquid nitrogen, but without all the facilities needed for a CR, would reduce the noise of' such detectors. This CR-light should preferably be small and the silicon detector should be placed behind the needed window so that window effects are minimised and full advantage of the method is obtained. The disadvantages by this suggested set-up are that the system is more complex and requires vacuum. In addition, the temperature differences will cause condensation problems, which also have to be handled. The uncertainties are obtained with a power levels in the order of 1 microW per nm. If we had access to a smoothly varying spectrally selective system with higher throughput, we expect to reduce the uncertainties accordingly. This could be a continuous laser source or a monochromator system and source with higher brightness. On the other hand, the cost of such a system would be rather high, so the main advantage with the presented methods would therefore be reduced. The evolution of self-calibration is going further. Geist et al has suggested to cool the silicon detectors down to cryogenic temperatures in order to achieve an ultra high accuracy primary standard below the I ppm level. Gran has initiated a NICe (Nordic Innovations Centre) funded project with custom designed silicon detectors where half of the surface is covered with a

Main Achievements 2003-2004 - Interdisciplinary Research - Radiation detection methods for health, earth and environmental sciences - Thermoluminescence (TL) detectors

International Nuclear Information System (INIS)

2005-01-01

The IFJ has over 35 years of experience in the development, production and application of new types of thermoluminescence (TL) detectors, particularly LiF:Mg,Ti and LiF:Mg,Cu,P. Over 600,000 LiF detectors produced at the IFJ PAN are routinely applied in dosimetry services and hospitals in 30 countries. The current research in the field of thermoluminescence concentrates in space dosimetry and novel 2-dimensional detectors for medical applications. The space project (named Matroshka), organized by the European Space Agency, is one of the most ambitious dosimetry experiments in space. In February 2004 an anatomical model of the human body (a humanoid phantom), equipped with over 3500 dedicated thermoluminescent detectors (TLD), developed and produced at IFJ and tested at the Chiba heavy ion accelerator in Japan, was installed outside the International Space Station (ISS) to determine the cosmic radiation doses absorbed in human organs, which would be experienced by astronauts in open space. The phantom will remain in space for one year, after which the detectors will be returned to the IFJ for analysis

Comparison of bulk and epitaxial 4H-SiC detectors for radiation hard particle tracking

CERN Document Server

Quinn, T; Bruzzi, M; Cunningham, W; Mathieson, K; Moll, M; Nelson, T; Nilsson, H E; Pintillie, I; Rahman, M; Reynolds, L; Sciortino, S; Sellin, P J; Strachan, H; Svensson, B G; Vaitkus, J

2003-01-01

Measurements and simulations have been carried out using bulk and epitaxial SiC detectors. Samples were irradiated to fluences of around 10**1**4 hardrons/cm**2. Material of thickness 40um gave a charge collection efficiency of 100% dropping to around 60% at 100mum thickness. Detailed MEDICI simulations incorporated the main defect levels in SiC, the vanadium center, Z-center and a mid-gap level as measured by deep level transient spectroscopy and other techniques. Calculated recombination currents and charge collection efficiencies at varying fluences were comparable to experimental data. The study suggests that SiC detectors will operate up to fluences around 10 **1**6/cm**2 as required by future particle physics experiments.

Particle Detectors: Research and Development at CERN

International Nuclear Information System (INIS)

Fabjan, C. W.

2008-01-01

Over the past 15 years a worldwide Detector R and D Programme has made the LHC experiments possible. These experiments operate at a new level of event rate and detection capabilities. Based on these advances, Detector R and D is continuing at CERN in close collaboration with University and Research Institutes. Several main directions are being pursued for solid-state and gaseous tracking devices, advanced crystal and noble liquid calorimetry, particle identification methods, and advanced signal-processing techniques. This effort is directed towards experiments at even higher collision rates at the LHC, the requirements for the next generation of linear electron-positron colliders and for applications outside particle physics, such as medical diagnostics instrumentation. We shall illustrate this challenging, stimulating and creative programme with examples and show how these developments are taking place in close collaboration between CERN and institutions around the globe

GaAs detectors with an ultra-thin Schottky contact for spectrometry of charged particles

Energy Technology Data Exchange (ETDEWEB)

Chernykh, S.V., E-mail: chsv_84@mail.ru [National University of Science and Technology “MISIS”, Moscow (Russian Federation); Research Institute of Experimental and Theoretical Physics, Almaty (Kazakhstan); Chernykh, A.V. [National University of Science and Technology “MISIS”, Moscow (Russian Federation); Didenko, S.I.; Baryshnikov, F.M. [National University of Science and Technology “MISIS”, Moscow (Russian Federation); Research Institute of Experimental and Theoretical Physics, Almaty (Kazakhstan); Burtebayev, N. [Research Institute of Experimental and Theoretical Physics, Almaty (Kazakhstan); Institute of Nuclear Physics, Almaty (Kazakhstan); Britvich, G.I. [Institute of High Energy Physics, Protvino, Moscow region (Russian Federation); Chubenko, A.P. [Research Institute of Experimental and Theoretical Physics, Almaty (Kazakhstan); P.N. Lebedev Physical Institute of the Russian Academy of Sciences, Moscow (Russian Federation); Guly, V.G.; Glybin, Yu.N. [LLC “SNIIP Plus”, Moscow (Russian Federation); Zholdybayev, T.K.; Burtebayeva, J.T.; Nassurlla, M. [Research Institute of Experimental and Theoretical Physics, Almaty (Kazakhstan); Institute of Nuclear Physics, Almaty (Kazakhstan)

2017-02-11

For the first time, samples of particle detectors based on high-purity GaAs epilayers with an active area of 25 and 80 mm{sup 2} and an ultra-thin Pt Schottky barrier were fabricated for use in the spectrometry of charged particles and their operating characteristics were studied. The obtained FWHM of 14.2 (for 25 mm{sup 2} detector) and 15.5 keV (for 80 mm{sup 2} detector) on the 5.499 MeV line of {sup 238}Pu is at the level of silicon spectrometric detectors. It was found that the main component that determines the energy resolution of the detector is a fluctuation in the number of collected electron–hole pairs. This allows us to state that the obtained energy resolution is close to the limit for VPE GaAs. - Highlights: • VPE GaAs particle detectors with an active area of 25 and 80 mm{sup 2} were fabricated. • 120 Å ultra-thin Pt Schottky barrier was used as a rectifying contact. • The obtained FWHM of 14.2 keV ({sup 238}Pu) is at the level of Si spectrometric detectors. • Various components of the total energy resolution were analyzed. • It was shown that obtained energy resolution is close to its limit for VPE GaAs.

Radiation Levels around the LHC

CERN Document Server

Mala, P; Calviani, M; Nordt, A

2013-01-01

This work discuss on the radiation levels measured around the LHC machine during the 2012 operational year. The doses and particle fluences are measured primarily by RadMon detectors – about 300 RadMons are installed around the accelerator – and by thermoluminescent detectors. In addition, BLMs, IG5/PMI ionisation chambers as well as FGCs can be used for corresponding cumulated dose evaluations. The probability of SEE depends directly on the high-energy hadron (HEH) fluence, so this is the main parameter that is calculated based on RadMons counts.

CADrx for GBM Brain Tumors: Predicting Treatment Response from Changes in Diffusion-Weighted MRI

Directory of Open Access Journals (Sweden)

Matthew S. Brown

2009-11-01

Full Text Available The goal of this study was to develop a computer-aided therapeutic response (CADrx system for early prediction of drug treatment response for glioblastoma multiforme (GBM brain tumors with diffusion weighted (DW MR images. In conventional Macdonald assessment, tumor response is assessed nine weeks or more post-treatment. However, we will investigate the ability of DW-MRI to assess response earlier, at five weeks post treatment. The apparent diffusion coefficient (ADC map, calculated from DW images, has been shown to reveal changes in the tumor’s microenvironment preceding morphologic tumor changes. ADC values in treated brain tumors could theoretically both increase due to the cell kill (and thus reduced cell density and decrease due to inhibition of edema. In this study, we investigated the effectiveness of features that quantify changes from pre- and post-treatment tumor ADC histograms to detect treatment response. There are three parts to this study: first, tumor regions were segmented on T1w contrast enhanced images by Otsu’s thresholding method, and mapped from T1w images onto ADC images by a 3D region of interest (ROI mapping tool using DICOM header information; second, ADC histograms of the tumor region were extracted from both pre- and five weeks post-treatment scans, and fitted by a two-component Gaussian mixture model (GMM. The GMM features as well as standard histogram-based features were extracted. Finally, supervised machine learning techniques were applied for classification of responders or non-responders. The approach was evaluated with a dataset of 85 patients with GBM under chemotherapy, in which 39 responded and 46 did not, based on tumor volume reduction. We compared adaBoost, random forest and support vector machine classification algorithms, using ten-fold cross validation, resulting in the best accuracy of 69.41% and the corresponding area under the curve (Az of 0.70.

Physical principles of semiconductor detectors

International Nuclear Information System (INIS)

Micek, S.L.

1979-01-01

The general properties of semiconductors with respect to the possibilities of their use as the ionization radiation detectors are discussed. Some chosen types of semiconductor junctions and their characteristics are briefly presented. There are also discussed the physical phenomena connected with the formation of barriers in various types of semiconductor counters. Finally, the basic properties of three main types of semiconductor detectors are given. (author)

Protecting detectors in ALICE

International Nuclear Information System (INIS)

Lechman, M.; Augustinus, A.; Chochula, P.; Di Mauro, A.; Stig Jirden, L.; Rosinsky, P.; Schindler, H.; Cataldo, G. de; Pinazza, O.; Kurepin, A.; Moreno, A.

2012-01-01

ALICE (A Large Ion Collider Experiment) is one of the big LHC (Large Hadron Collider) experiments at CERN in Geneva. It is composed of many sophisticated and complex detectors mounted very compactly around the beam pipe. Each detector is a unique masterpiece of design, engineering and construction and any damage to it could stop the experiment for months or even for years. It is therefore essential that the detectors are protected from any danger and this is one very important role of the Detector Control System (DCS). One of the main dangers for the detectors is the particle beam itself. Since the detectors are designed to be extremely sensitive to particles they are also vulnerable to any excess of beam conditions provided by the LHC accelerator. The beam protection consists of a combination of hardware interlocks and control software and this paper will describe how this is implemented and handled in ALICE. Tools have also been developed to support operators and shift leaders in the decision making related to beam safety. The gained experiences and conclusions from the individual safety projects are also presented. (authors)

Induced Charge Fluctuations in Semiconductor Detectors with a Cylindrical Geometry

Science.gov (United States)

Samedov, Victor V.

2018-01-01

Now, compound semiconductors are very appealing for hard X-ray room-temperature detectors for medical and astrophysical applications. Despite the attractive properties of compound semiconductors, such as high atomic number, high density, wide band gap, low chemical reactivity and long-term stability, poor hole and electron mobility-lifetime products degrade the energy resolution of these detectors. The main objective of the present study is in development of a mathematical model of the process of the charge induction in a cylindrical geometry with accounting for the charge carrier trapping. The formulae for the moments of the distribution function of the induced charge and the formulae for the mean amplitude and the variance of the signal at the output of the semiconductor detector with a cylindrical geometry were derived. It was shown that the power series expansions of the detector amplitude and the variance in terms of the inverse bias voltage allow determining the Fano factor, electron mobility lifetime product, and the nonuniformity level of the trap density of the semiconductor material.

Development of ALICE microstrip detectors at IRST

International Nuclear Information System (INIS)

Boscardin, M.; Bosisio, L.; Dalla Betta, G.-F.; Gregori, P.; Rachevskaia, I.; Zorzi, N.

2001-01-01

We report on the development of double-sided, AC-coupled, microstrip detectors oriented to the A Large Ion Collider Experiment (ALICE). The main design and processing issues are presented, together with some selected results from the electrical characterization of detectors and related test structures

History of infrared detectors

Science.gov (United States)

Rogalski, A.

2012-09-01

This paper overviews the history of infrared detector materials starting with Herschel's experiment with thermometer on February 11th, 1800. Infrared detectors are in general used to detect, image, and measure patterns of the thermal heat radiation which all objects emit. At the beginning, their development was connected with thermal detectors, such as thermocouples and bolometers, which are still used today and which are generally sensitive to all infrared wavelengths and operate at room temperature. The second kind of detectors, called the photon detectors, was mainly developed during the 20th Century to improve sensitivity and response time. These detectors have been extensively developed since the 1940's. Lead sulphide (PbS) was the first practical IR detector with sensitivity to infrared wavelengths up to ˜3 μm. After World War II infrared detector technology development was and continues to be primarily driven by military applications. Discovery of variable band gap HgCdTe ternary alloy by Lawson and co-workers in 1959 opened a new area in IR detector technology and has provided an unprecedented degree of freedom in infrared detector design. Many of these advances were transferred to IR astronomy from Departments of Defence research. Later on civilian applications of infrared technology are frequently called "dual-use technology applications." One should point out the growing utilisation of IR technologies in the civilian sphere based on the use of new materials and technologies, as well as the noticeable price decrease in these high cost technologies. In the last four decades different types of detectors are combined with electronic readouts to make detector focal plane arrays (FPAs). Development in FPA technology has revolutionized infrared imaging. Progress in integrated circuit design and fabrication techniques has resulted in continued rapid growth in the size and performance of these solid state arrays.

Aboveground roofed design for the disposal of low-level radioactive waste in Maine

Energy Technology Data Exchange (ETDEWEB)

Alexander, J.A. [Univ. of Maine, Orono, ME (United States)

1993-03-01

The conceptual designs proposed in this report resulted from a study for the Maine Low-level Radioactive Waste Authority to develop conceptual designs for a safe and reliable disposal facility for Maine`s low-level radioactive waste (LLW). Freezing temperatures, heavy rainfall, high groundwater tables, and very complex and shallow glaciated soils found in Maine place severe constraints on the design. The fundamental idea behind the study was to consider Maine`s climatic and geological conditions at the beginning of conceptual design rather than starting with a design for another location and adapting it for Maine`s conditions. The conceptual designs recommended are entirely above ground and consist of an inner vault designed to provide shielding and protection against inadvertent intrusion and an outer building to protect the inner vault from water. The air dry conditions within the outer building should lead to almost indefinite service life for the concrete inner vault and the waste containers. This concept differs sharply from the usual aboveground vault in its reliance on at least two independent, but more or less conventional, roofing systems for primary and secondary protection against leakage of radioisotopes from the facility. Features include disposal of waste in air dry environment, waste loading and visual inspection by remote-controlled overhead cranes, and reliance on engineered soils for tertiary protection against release of radioactive materials.

SuperCDMS Underground Detector Fabrication Facility

Energy Technology Data Exchange (ETDEWEB)

Platt, M.; Mahapatra, R.; Bunker, Raymond A.; Orrell, John L.

2018-03-01

The SuperCDMS SNOLAB dark matter experiment processes Ge and Si crystals into fully tested phonon and ionization detectors at surface fabrication and test facilities. If not mitigated, it is anticipated that trace-level production of radioisotopes in the crystals due to exposure to cosmic rays at (or above) sea level will result in the dominant source of background events in future dark matter searches using the current SuperCDMS detector technology. Fabrication and testing of detectors in underground facilities shielded from cosmic radiation is one way to directly reduce production of trace levels of radioisotopes, thereby improving experimental sensitivity for the discovery of dark matter beyond the level of the current experiment. In this report, we investigate the cost and feasibility to establish a complete detector fabrication processing chain in an underground location to mitigate cosmogenic activation of the Ge and Si detector substrates. For a specific and concrete evaluation, we explore options for such a facility located at SNOLAB, an underground laboratory in Sudbury, Canada hosting the current and future experimental phases of SuperCDMS.

Report of the general purpose detector group

International Nuclear Information System (INIS)

Barbaro-Galtieri, A.; Bartel, W.; Bulos, F.; Cool, R.; Hanson, G.; Koetz, U.; Kottahaus, R.; Loken, S.; Luke, D.; Rothenberg, A.

1975-01-01

A general purpose detector for PEP is described. The main components of this detector are a l meter radius, 15 kilogauss superconducting solenoidal magnet with drift chambers to detect and measure the momentum of charged particles, a liquid argon neutral detector and hadron calorimeter, and a system of Cherenkov and time-of-flight counters for identification of charged hadrons. A major consideration in the design of this detector was that it be flexible: the magnet coil and drift chambers form a core around which various apparatus for specialized detection can be placed

Plastic scintillator detector for pulsed flux measurements

Science.gov (United States)

Kadilin, V. V.; Kaplun, A. A.; Taraskin, A. A.

2017-01-01

A neutron detector, providing charged particle detection capability, has been designed. The main purpose of the detector is to measure pulsed fluxes of both charged particles and neutrons during scientific experiments. The detector consists of commonly used neutron-sensitive ZnS(Ag) / 6LiF scintillator screens wrapping a layer of polystyrene based scintillator (BC-454, EJ-254 or equivalent boron loaded plastic). This type of detector design is able to log a spatial distribution of events and may be scaled to any size. Different variations of the design were considered and modelled in specialized toolkits. The article presents a review of the detector design features as well as simulation results.

Deep defect levels in standard and oxygen enriched silicon detectors before and after **6**0Co-gamma-irradiation

CERN Document Server

Stahl, J; Lindström, G; Pintilie, I

2003-01-01

Capacitance Deep Level Transient Spectroscopy (C-DLTS) measurements have been performed on standard and oxygen-doped silicon detectors manufactured from high-resistivity n-type float zone material with left angle bracket 111 right angle bracket and left angle bracket 100 right angle bracket orientation. Three different oxygen concentrations were achieved by the so-called diffusion oxygenated float zone (DOFZ) process initiated by the CERN-RD48 (ROSE) collaboration. Before the irradiation a material characterization has been performed. In contrast to radiation damage by neutrons or high- energy charged hadrons, were the bulk damage is dominated by a mixture of clusters and point defects, the bulk damage caused by **6**0Co-gamma-radiation is only due to the introduction of point defects. The dominant electrically active defects which have been detected after **6**0Co-gamma-irradiation by C-DLTS are the electron traps VO//i, C//iC//s, V//2( = /-), V //2(-/0) and the hole trap C//i O//i. The main difference betwe...

Calculation of the time fixation accuracy for Si(Li)-detectors

International Nuclear Information System (INIS)

Kondrat'ev, V.P.; Krasnov, L.V.

1981-01-01

An accuracy of time fixation to pulses of changing shape for li-frifted si detectors with thickness over 1 mm is evaluated. The method of the comparison of main and converted signal shapes is the most universal method of time fixation. The idea of the method consists in shaping a bipolar pulse using a single-polar input Rulse and recording the point of the bipolar signal intersection with the zero level. The combination of an analytical method with numerical computer calculations is used for evaluating the time fixation fluctuations. Analysis of the results obtained shows that the value of delay p=tausub(d)/tausub(n) (where tausub(d) is delay time for the main part of a signal, tausub(n) is the maximum time of electron collection) affects most strongly the time shift. The parameter K=tausub(i)/tausub(n) (tausub(i) is a constant of integrating circuit) affects slightly the maximum value of time shift. For the li-drifted si detector 2 mm thick with dispattacement vottage of 400 V the moment of the time fixation will be equal to 47 is in the case of K--1, p=0.4 and x=0.25 (x=R/i, where R is a particle range in the detector, l is the thickness of the detector depleted area. The fluctuations in time fixation don't exceed 2.3 ns for the whole particle energy range

ATLAS ITk Pixel detector

CERN Document Server

Gemme, Claudia; The ATLAS collaboration

2016-01-01

The high luminosity upgrade of the LHC (HL-LHC) in 2026 will provide new challenge to the ATLAS tracker. The current inner detector will be replaced with a whole silicon tracker which will consist of a five barrel layer Pixel detector surrounded by a four barrel layer Strip detector. The expected high radiation level are requiring the development of upgraded silicon sensors as well as new a front-end chip. The dense tracking environment will require finer granularity detectors. The data rates will require new technologies for high bandwidth data transmission and handling. The current status of the HL-LHC ATLA Pixel detector developments as well as the various layout options will be reviewed.

326 Ion-spraying type atmospheric radon detector

International Nuclear Information System (INIS)

Wu Xinmin; Liu Qingchen; Liu Yujuan; Li Shumin; Yang Yaxin

2005-01-01

The advantages and disadvantages of atmospheric absolute radon detector were briefly analyzed in this paper. The working principle, structure and main technical capability of the 326 ion-spraying type atmospheric radon detector were introduced. Finally, its disadvantages and the improved aspects in the future were discussed. (authors)

Role of extent of resection on quality of life in patients with newly diagnosed GBM.

Science.gov (United States)

Choudry, Usama Khalid; Shaikh, Huzaifa Ismail; Nisar, Areeba; Khan, Saad Akhtar; Shamim, Muhammad Shahzad

2018-01-01

Glioblastomas known for their adverse outcomes are most reportedly managed by surgical resection. Studies on the impact of (Extent of Resection) EOR against Quality of Life (QOL) are very limited. We have collected data from recent studies in this review to extract a general consensus among the neurosurgeons regarding the EOR. Key parameters like functional independence, neurocognitive improvements and global health status have been explored in the context of QOL. The currently available data suggests that an increased EOR may help improve QOL in GBM patients. With the help of recent advancements it may be possible to attain a better extent of resection while operating on GBMs.

Modelling the increased frequency of extreme sea levels in the Ganges-Brahmaputra-Meghna delta due to sea level rise and other effects of climate change.

Science.gov (United States)

Kay, S; Caesar, J; Wolf, J; Bricheno, L; Nicholls, R J; Saiful Islam, A K M; Haque, A; Pardaens, A; Lowe, J A

2015-07-01

Coastal flooding due to storm surge and high tides is a serious risk for inhabitants of the Ganges-Brahmaputra-Meghna (GBM) delta, as much of the land is close to sea level. Climate change could lead to large areas of land being subject to increased flooding, salinization and ultimate abandonment in West Bengal, India, and Bangladesh. IPCC 5th assessment modelling of sea level rise and estimates of subsidence rates from the EU IMPACT2C project suggest that sea level in the GBM delta region may rise by 0.63 to 0.88 m by 2090, with some studies suggesting this could be up to 0.5 m higher if potential substantial melting of the West Antarctic ice sheet is included. These sea level rise scenarios lead to increased frequency of high water coastal events. Any effect of climate change on the frequency and severity of storms can also have an effect on extreme sea levels. A shelf-sea model of the Bay of Bengal has been used to investigate how the combined effect of sea level rise and changes in other environmental conditions under climate change may alter the frequency of extreme sea level events for the period 1971 to 2099. The model was forced using atmospheric and oceanic boundary conditions derived from climate model projections and the future scenario increase in sea level was applied at its ocean boundary. The model results show an increased likelihood of extreme sea level events through the 21st century, with the frequency of events increasing greatly in the second half of the century: water levels that occurred at decadal time intervals under present-day model conditions occurred in most years by the middle of the 21st century and 3-15 times per year by 2100. The heights of the most extreme events tend to increase more in the first half of the century than the second. The modelled scenarios provide a case study of how sea level rise and other effects of climate change may combine to produce a greatly increased threat to life and property in the GBM delta by the end

Global tracker for the ALICE high level trigger

International Nuclear Information System (INIS)

Vik, Thomas

2006-01-01

This thesis deals with two main topics. The first is the implementation and testing of a Kalman filter algorithm in the HLT (High Level Trigger) reconstruction code. This will perform the global tracking in the HLT, that is merging tracklets and hits from the different sub-detectors in the central barrel detector. The second topic is a trigger mode of the HLT which uses the global tracking of particles through the TRD (Transition Radiation Detector), TPC (Time Projection Chamber) and the ITS (Inner Tracking System): The dielectron trigger. Global tracking: The Kalman filter algorithm has been introduced to the HLT tracking scheme. (Author)

Investigation about semiconductor gamma ray detector - Evaluation of Ge(Li) detectors life expectation

International Nuclear Information System (INIS)

1980-06-01

A list of germanium lithium gamma ray detectors has been drawn up by a working group after investigations in various laboratories. Authors analyse the historical account of each detector and try to give an answer about some questions as: - detectors life expectation, - deficiencies and death reasons, - influence of detector type and volume. Differents parameters are also collected by the working group for future works (standard geometry, low level measurements, etc.). In the list, the characteristics of 228 detectors, collected between january 1965 and december 1977 are put together. The principal conclusions of the authors are: - with a probability of 95%, half of the detectors is dead before 6.1 years, - the average age of dead population (33% of detectors) is 3.9 years, - resolution and efficiency evolution are good indicators of possible deficiency, - the fiability of vertical cryostat is better than the other systems [fr

DARWIN: towards the ultimate dark matter detector

Science.gov (United States)

Aalbers, J.; Agostini, F.; Alfonsi, M.; Amaro, F. D.; Amsler, C.; Aprile, E.; Arazi, L.; Arneodo, F.; Barrow, P.; Baudis, L.; Benabderrahmane, M. L.; Berger, T.; Beskers, B.; Breskin, A.; Breur, P. A.; Brown, A.; Brown, E.; Bruenner, S.; Bruno, G.; Budnik, R.; Bütikofer, L.; Calvén, J.; Cardoso, J. M. R.; Cichon, D.; Coderre, D.; Colijn, A. P.; Conrad, J.; Cussonneau, J. P.; Decowski, M. P.; Diglio, S.; Drexlin, G.; Duchovni, E.; Erdal, E.; Eurin, G.; Ferella, A.; Fieguth, A.; Fulgione, W.; Gallo Rosso, A.; Di Gangi, P.; Di Giovanni, A.; Galloway, M.; Garbini, M.; Geis, C.; Glueck, F.; Grandi, L.; Greene, Z.; Grignon, C.; Hasterok, C.; Hannen, V.; Hogenbirk, E.; Howlett, J.; Hilk, D.; Hils, C.; James, A.; Kaminsky, B.; Kazama, S.; Kilminster, B.; Kish, A.; Krauss, L. M.; Landsman, H.; Lang, R. F.; Lin, Q.; Linde, F. L.; Lindemann, S.; Lindner, M.; Lopes, J. A. M.; Marrodán Undagoitia, T.; Masbou, J.; Massoli, F. V.; Mayani, D.; Messina, M.; Micheneau, K.; Molinario, A.; Morå, K. D.; Morteau, E.; Murra, M.; Naganoma, J.; Newstead, J. L.; Ni, K.; Oberlack, U.; Pakarha, P.; Pelssers, B.; de Perio, P.; Persiani, R.; Piastra, F.; Piro, M. C.; Plante, G.; Rauch, L.; Reichard, S.; Rizzo, A.; Rupp, N.; Dos Santos, J. M. F.; Sartorelli, G.; Scheibelhut, M.; Schindler, S.; Schumann, M.; Schreiner, J.; Scotto Lavina, L.; Selvi, M.; Shagin, P.; Silva, M. C.; Simgen, H.; Sissol, P.; von Sivers, M.; Thers, D.; Thurn, J.; Tiseni, A.; Trotta, R.; Tunnell, C. D.; Valerius, K.; Vargas, M. A.; Wang, H.; Wei, Y.; Weinheimer, C.; Wester, T.; Wulf, J.; Zhang, Y.; Zhu, T.; Zuber, K.

2016-11-01

DARk matter WImp search with liquid xenoN (DARWIN) will be an experiment for the direct detection of dark matter using a multi-ton liquid xenon time projection chamber at its core. Its primary goal will be to explore the experimentally accessible parameter space for Weakly Interacting Massive Particles (WIMPs) in a wide mass-range, until neutrino interactions with the target become an irreducible background. The prompt scintillation light and the charge signals induced by particle interactions in the xenon will be observed by VUV sensitive, ultra-low background photosensors. Besides its excellent sensitivity to WIMPs above a mass of 5 GeV/c2, such a detector with its large mass, low-energy threshold and ultra-low background level will also be sensitive to other rare interactions. It will search for solar axions, galactic axion-like particles and the neutrinoless double-beta decay of 136Xe, as well as measure the low-energy solar neutrino flux with detect galactic supernovae. We present the concept of the DARWIN detector and discuss its physics reach, the main sources of backgrounds and the ongoing detector design and R&D efforts.

DARWIN: towards the ultimate dark matter detector

Energy Technology Data Exchange (ETDEWEB)

Aalbers, J.; Breur, P.A.; Brown, A. [Nikhef and the University of Amsterdam, Amsterdam (Netherlands); Agostini, F. [Department of Physics and Astrophysics, University of Bologna and INFN-Bologna, Bologna (Italy); Alfonsi, M.; Beskers, B. [Institut für Physik and Exzellenzcluster PRISMA, Johannes Gutenberg-Universität Mainz, Mainz (Germany); Amaro, F.D. [Department of Physics, University of Coimbra, Coimbra (Portugal); Amsler, C. [Albert Einstein Center for Fundamental Physics, Universität Bern, Bern (Switzerland); Aprile, E. [Physics Department, Columbia University, New York, NY (United States); Arazi, L.; Breskin, A.; Budnik, R. [Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot (Israel); Arneodo, F.; Benabderrahmane, M.L. [New York University Abu Dhabi (United Arab Emirates); Barrow, P.; Baudis, L. [Physik-Institut, Universität Zürich, Zürich (Switzerland); Berger, T.; Brown, E. [Department of Physics, Applied Physics and Astronomy, Rensselaer Polytechnic Institute, Troy, NY (United States); Bruenner, S. [Max-Planck-Institut für Kernphysik, Heidelberg (Germany); Bruno, G., E-mail: lior.arazi@weizmann.ac.il, E-mail: laura.baudis@physik.uzh.ch, E-mail: amos.breskin@weizmann.ac.il, E-mail: decowski@nikhef.nl, E-mail: marc.schumann@lhep.unibe.ch [INFN-Laboratori Nazionali del Gran Sasso and Gran Sasso Science Institute, L' Aquila (Italy); and others

2016-11-01

DARk matter WImp search with liquid xenoN (DARWIN) will be an experiment for the direct detection of dark matter using a multi-ton liquid xenon time projection chamber at its core. Its primary goal will be to explore the experimentally accessible parameter space for Weakly Interacting Massive Particles (WIMPs) in a wide mass-range, until neutrino interactions with the target become an irreducible background. The prompt scintillation light and the charge signals induced by particle interactions in the xenon will be observed by VUV sensitive, ultra-low background photosensors. Besides its excellent sensitivity to WIMPs above a mass of 5 GeV/ c {sup 2}, such a detector with its large mass, low-energy threshold and ultra-low background level will also be sensitive to other rare interactions. It will search for solar axions, galactic axion-like particles and the neutrinoless double-beta decay of {sup 136}Xe, as well as measure the low-energy solar neutrino flux with < 1% precision, observe coherent neutrino-nucleus interactions, and detect galactic supernovae. We present the concept of the DARWIN detector and discuss its physics reach, the main sources of backgrounds and the ongoing detector design and R and D efforts.

Effect of SiO$_{2}$ passivating layer in segmented silicon planar detectors on the detector response

CERN Document Server

Verbitskaya, Elena; Eremin, Vladimir; Golubkov, S; Konkov, K; Roe, Shaun; Ruggiero, G; Sidorov, A; Weilhammer, Peter

2004-01-01

Silicon detectors with a fine segmentation (micropixel and microstrip) are the main type of detectors used in the inner trackers of LHC experiments. Due to the high luminosity of the LHC machines they are required to have a fast response to fit the short shaping time of 25 ns and to be radiation hard. Evaluation of silicon microstrip detectors developed for the ATLAS silicon tracker and carried out under collaboration of CERN and PTI has shown the reversal of the pulse polarity in the detector response to short- range radiation. Since the negative signal is of about 30% of the normal positive one, the effect strongly reduces the charge collection efficiency in irradiated detectors. The investigation presents the consideration on the origin of a negative response in Si microstrip detectors and the experimental proof of the model. The study of the effect has been carried out using "baby" strip detectors with a special design: each strip has a window in a metallization, which covers the p/sup +/ implant. The sca...

Immunohistochemically determined total epidermal growth factor receptor levels not of prognostic value in newly diagnosed glioblastoma multiforme: Report from the Radiation Therapy Oncology Group

International Nuclear Information System (INIS)

Chakravarti, Arnab; Seiferheld, Wendy; Tu Xiaoyu; Wang Huijun; Zhang Huazhong; Ang, K. Kian; Hammond, Elizabeth; Curran, Walter; Mehta, Minesh

2005-01-01

Purpose: The Radiation Therapy Oncology Group (RTOG) performed an analysis of patterns of immunohistochemically detected total epidermal growth factor receptor (EGFR) protein expression levels and their prognostic significance on archival tissue in newly diagnosed glioblastoma multiforme (GBM) patients from prior prospective RTOG clinical trials. Methods and materials: Patients in this study had been treated on previous RTOG GBM trials (RTOG 7401, 7918, 8302, 8409, 9006, 9305, 9602, and 9806). Tissue microarrays were prepared from 155 patients enrolled in these trials. These specimens were stained using a mouse monoclonal antibody specific for the extracellular binding domain of EGFR to detect total EGFR (including both wild-type phosphorylated and wild-type unphosphorylated isoforms with some cross-reactivity with EGFRvIII). The intensity of total EGFR protein expression was measured by computerized quantitative image analysis using the SAMBA 4000 Cell Image Analysis System. The parameters measured were the mean optical densities over the labeled areas and the staining index, which represents the proportion of stained area relative to the mean stain concentration. Both parameters were correlated with the clinical outcome. Results: No differences in either overall or progression-free survival could be demonstrated by the mean optical density class or mean optical density quartile or the staining index of total EGFR immunostaining among the representative RTOG GBM cases. Conclusion: Total EGFR protein expression levels, as measured immunohistochemically, do not appear to be of prognostic value in newly diagnosed GBM patients. Given the accumulating clinical evidence of the activity of anti-EGFR agents in GBM and the preclinical data suggesting the important role of downstream mediators as effectors of EGFR signaling, the RTOG is conducting additional investigations into the prognostic value of activation patterns of EGFR signaling, both at the level of the receptor

Cosmic-ray-veto detector system

International Nuclear Information System (INIS)

Miller, D.W.; Menlove, H.O.

1992-12-01

To reduce the cosmic-ray-induced neutron background, we are testing a cosmic-ray veto option with a neutron detector system that uses plastic scintillator slabs mounted on the outside of a 3 He-tube detector. The scintillator slabs eliminate unwanted cosmic-ray events, enabling the detector to assay low-level plutonium samples, for which a low-background coincident signature is critical. This report describes the design and testing of the prototype cosmic-ray-veto detector system

Status of radiation detector and neutron monitor technology

CERN Document Server

Kim, Y K; Ha, J H; Han, S H; Hong, S B; Hwang, I K; Lee, W G; Moon, B S; Park, S H; Song, M H

2002-01-01

In this report, we describe the current states of the radiation detection technology, detectors for industrial application, and neutron monitors. We also survey the new technologies being applied to this field. The method to detect radiation is the measurement of the observable secondary effect from the interaction between incident radiation and detector material, such as ionization, excitation, fluorescence, and chemical reaction. The radiation detectors can be categorized into gas detectors, scintillation detectors, and semiconductor detectors according to major effects and main applications. This report contains the current status and operational principles of these detectors. The application fields of radiation detectors are industrial measurement system, in-core neutron monitor, medical radiation diagnostic device, nondestructive inspection device, environmental radiation monitoring, cosmic-ray measurement, security system, fundamental science experiment, and radiation measurement standardization. The st...

Characterization of biological features of a rat F98 GBM model: A PET-MRI study with [18F]FAZA and [18F]FDG

International Nuclear Information System (INIS)

Belloli, Sara; Brioschi, Andrea; Politi, Letterio Salvatore; Ronchetti, Francesca; Calderoni, Sara; Raccagni, Isabella; Pagani, Antonella; Monterisi, Cristina; Zenga, Francesco; Zara, Gianpaolo; Fazio, Ferruccio; Mauro, Alessandro

2013-01-01

Introduction: The prognosis of malignant gliomas remains largely unsatisfactory for the intrinsic characteristics of the pathology and for the delayed diagnosis. Multimodal imaging based on PET and MRI may assess the dynamics of disease onset and progression allowing the validation of preclinical models of glioblastoma multiforme (GBM). The aim of this study was the characterization of a syngeneic rat model of GBM using combined in vivo imaging and immunohistochemistry. Methods: Four groups of Fischer rats were implanted in a subcortical region with increasing concentration of rat glioma F98 cells and weekly monitored with Gd-MR, [ 18 F]FDG- and [ 18 F]FAZA-PET starting one week after surgery. Different targets were evaluated on post mortem brain specimens using immunohistochemistry: VEGF, GFAP, HIF-1α, Ki-67 and nestin. Results: Imaging results indicated that tumor onset but not progression was related to the number of F98 cells. Hypoxic regions identified with [ 18 F]FAZA and high-glucose metabolism regions recognized with [ 18 F]FDG were located respectively in the core and in external areas of the tumor, with partial overlap and remodeling during disease progression. Histological and immunohistochemical analysis confirmed PET/MRI results and revealed that our model resumes biological characteristics of human GBM. IHC and PET studies showed that necrotic regions, defined on the basis of [ 18 F]FDG uptake reduction, may include hypoxic clusters of vital tumor tissue identified with [ 18 F]FAZA. This last information is particularly relevant for the identification of the target volume during image-guided radiotherapy. Conclusions: In conclusion, the combined use of PET and MRI allows in vivo monitoring of the biological modification of F98 lesions during tumor progression

Ruggedization of CdZnTe detectors and detector assemblies for radiation detection applications

Energy Technology Data Exchange (ETDEWEB)

Lu, P.H., E-mail: pinghe.lu@redlen.com; Gomolchuk, P.; Chen, H.; Beitz, D.; Grosser, A.W.

2015-06-01

This paper described improvements in the ruggedization of CdZnTe detectors and detector assemblies for use in radiation detection applications. Research included experimenting with various conductive and underfill adhesive material systems suitable for CZT substrates. A detector design with encapsulation patterning was developed to protect detector surfaces and to control spacing between CZT anode and PCB carrier. Robustness of bare detectors was evaluated through temperature cycling and metallization shear testing. Attachment processes using well-chosen adhesives and PCB carrier materials were optimized to improve reliability of detector assemblies, resulted in Improved Attachment Detector Assembly. These detector assemblies were subjected to aggressive temperature cycling, and varying levels of drop/shock and vibration, in accordance with modified JEDEC, ANSI and FedEx testing standards, to assess their ruggedness. Further enhanced detector assembly ruggedization methods were investigated involving adhesive conformal coating, potting and dam filling on detector assemblies, which resulted in the Enhanced Ruggedization Detector Assembly. Large numbers of CZT detectors and detector assemblies with 5 mm and 15 mm thick, over 200 in total, were tested. Their performance was evaluated by exposure to various radioactive sources using comprehensive predefined detector specifications and testing protocols. Detector assemblies from improved attachment and enhanced ruggedization showed stable performances during the harsh environmental condition tests. In conclusion, significant progress has been made in improving the reliability and enhancing the ruggedness of CZT detector assemblies for radiation detection applications deployed in operational environments. - Highlights: • We developed ruggedization methods to enhance reliability of CZT detector assemblies. • Attachment of CZT radiation detectors was improved through comparative studies. • Bare detector metallization

The resonant detector and its application to epithermal neutron spectroscopy

International Nuclear Information System (INIS)

Gorini, G.; Perelli-Cippo, E.; Tardocchi, M.; Andreani, C.; D'Angelo, A.; Pietropaolo, A.; Senesi, R.; Imberti, S.; Bracco, A.; Previtali, E.; Pessina, G.; Rhodes, N.J.; Schooneveld, E.M.

2004-01-01

New perspectives for epithermal neutron spectroscopy are being opened by the development of the resonant detector (RD) and its use on inverse geometry time of flight spectrometers at spallation sources. The RD was first proposed in the 1980s and was recently brought to a performance level exceeding conventional neutron-sensitive Li-glass scintillator detectors. It features a photon counter coupled to a neutron analyzer foil. Resonant neutron absorption in the foil results in the emission of prompt gamma rays that are detected in the photon counter. The dimensions of the RD set the spatial resolution that can be achieved, ranging from a fraction of a cm to several cm. It can thus be tailored to the construction of detector arrays of different geometry. The main results of the research on this kind of detector are reported leading to the present optimized RD design based on a combination of YAP scintillation photon counter and uranium or gold analyzer foils. This detector has already been selected for application in the upgrade of the VESUVIO spectrometer on ISIS. A special application is the Very Low Angle Detector (VLAD) bank, which will extend the kinematical region for neutron scattering to low momentum transfer ( -1 ) whilst still keeping energy transfer >1 eV, thus allowing new experimental studies in condensed matter systems. The first results of tests made with prototype VLAD detectors are presented, confirming the usefulness of the RD for measurements at scattering angles as low as 2-5 deg

Plastic scintillator detector for pulsed flux measurements

International Nuclear Information System (INIS)

Kadilin, V V; Kaplun, A A; Taraskin, A A

2017-01-01

A neutron detector, providing charged particle detection capability, has been designed. The main purpose of the detector is to measure pulsed fluxes of both charged particles and neutrons during scientific experiments. The detector consists of commonly used neutron-sensitive ZnS(Ag) / 6 LiF scintillator screens wrapping a layer of polystyrene based scintillator (BC-454, EJ-254 or equivalent boron loaded plastic). This type of detector design is able to log a spatial distribution of events and may be scaled to any size. Different variations of the design were considered and modelled in specialized toolkits. The article presents a review of the detector design features as well as simulation results. (paper)

The Fermi Gamma-ray Burst Monitor Instrument

International Nuclear Information System (INIS)

Bhat, P. N.; Briggs, M. S.; Connaughton, V.; Paciesas, W. S.; Preece, R. D.; Meegan, C. A.; Lichti, G. G.; Diehl, R.; Greiner, J.; Kienlin, A. von; Fishman, G. J.; Kouveliotou, C.; Kippen, R. M.

2009-01-01

The Fermi Gamma-ray Space Telescope launched on June 11, 2008 carries two experiments onboard--the Large Area Telescope (LAT) and the Gamma-ray Burst Monitor (GBM). The primary mission of the GBM instrument is to support the LAT in observing γ-ray bursts (GRBs) by providing low-energy measurements with high temporal and spectral resolution as well as rapid burst locations over a large field-of-view (≥8 sr). The GBM will complement the LAT measurements by observing GRBs in the energy range 8 keV to 40 MeV, the region of the spectral turnover in most GRBs. The GBM detector signals are processed by the onboard digital processing unit (DPU). We describe some of the hardware features of the DPU and its expected limitations during intense triggers.

Detector Plans for LS1

Energy Technology Data Exchange (ETDEWEB)

Nessi, M [European Organization for Nuclear Research, Geneva (Switzerland)

2012-07-01

All experiments plan an effective usage of the LS1 shutdown period. After three years of running they will go through a consolidation phase, mostly to fix problems that have emerged over time, like single points of failure in the infrastructure, failures of low voltage power supplies and optical links. Upgrades of some detector components will start, mainly related to the beam pipe, the innermost tracker elements and the trigger system. Detector components, which had to be staged for cost reasons in 2003, will then enter into the detector setup. The goal is to be fully ready for the new energy regime at nominal luminosity.

Main features of detectors and isotopes to investigate double beta decay with increased sensitivity

Science.gov (United States)

Barabash, A. S.

2018-03-01

The current situation in double beta decay experiments, the characteristics of modern detectors and the possibility of increasing the sensitivity to neutrino mass in future experiments are discussed. The issue of the production and use of enriched isotopes in double beta decay experiments is discussed in addition.

VizieR Online Data Catalog: GRB prompt emission fitted with the DREAM model (Ahlgren+, 2015)

Science.gov (United States)

Ahlgren, B.; Larsson, J.; Nymark, T.; Ryde, F.; Pe'Er, A.

2018-01-01

We illustrate the application of the DREAM model by fitting it to two different, bright Fermi GRBs; GRB 090618 and GRB 100724B. While GRB 090618 is well fitted by a Band function, GRB 100724B was the first example of a burst with a significant additional BB component (Guiriec et al. 2011ApJ...727L..33G). GRB 090618 is analysed using Gamma-ray Burst Monitor (GBM) data (Meegan et al. 2009ApJ...702..791M) from the NaI and BGO detectors. For GRB 100724B, we used GBM data from the NaI and BGO detectors as well as Large Area Telescope Low Energy (LAT-LLE) data. For both bursts we selected NaI detectors seeing the GRB at an off-axis angle lower than 60° and the BGO detector as being the best aligned of the two BGO detectors. The spectra were fitted in the energy ranges 8-1000 keV (NaI), 200-40000 keV (BGO) and 30-1000 MeV (LAT-LLE). (2 data files).

Molecular profiling of short-term and long-term surviving patients identifies CD34 mRNA level as prognostic for glioblastoma survival

DEFF Research Database (Denmark)

Michaelsen, Signe Regner; Urup, Thomas; Olsen, Lars Rønn

2018-01-01

Despite extensive treatment, overall survival (OS) for glioblastoma (GBM) remains poor. A small proportion of patients present long survival over 3 years, but the underlying molecular background separating these long-term survivors (LTS) from short-term survivors (STS) are insufficiently understood....... Accordingly, study aim was to identify independent prognostic biomarkers for survival. Study cohort consisted of 93 primary GBM patients treated with radiation-, chemo- and bevacizumab therapy, among which 14 STS (OS ≤ 12 months) and 6 LTS (OS ≥ 36 months) were identified, all confirmed being IDH wild......-type. RNA expression levels in diagnostic tumor specimen for 792 genes were analyzed by NanoString technology. While no differences were found with regard to GBM subtype between LTS versus STS, comparative analysis of individual genes identified 14 significantly differently expressed candidate genes...

Development of planar detectors with active edge

International Nuclear Information System (INIS)

Povoli, M.; Bagolini, A.; Boscardin, M.; Dalla Betta, G.-F.; Giacomini, G.; Vianello, E.; Zorzi, N.

2011-01-01

We report on the first batch of planar active edge sensors fabricated at Fondazione Bruno Kessler (Trento, Italy) on the way to the development of full 3D detectors with active edges. The main design and technological aspects are reported, along with selected results from the electrical characterization of detectors and test structures.

Development of planar detectors with active edge

Energy Technology Data Exchange (ETDEWEB)

Povoli, M., E-mail: povoli@disi.unitn.it [Dipartimento di Ingegneria e Scienza dell' Informazione, Universita di Trento, Via Sommarive, 14, I-38123 Povo di Trento (Italy); INFN, Sezione di Padova (Gruppo Collegato di Trento) (Italy); Bagolini, A.; Boscardin, M. [Fondazione Bruno Kessler, Centro per i Materiali e i Microsistemi (FBK-CMM), Via Sommarive, 18, I-38123 Povo di Trento (Italy); Dalla Betta, G.-F. [Dipartimento di Ingegneria e Scienza dell' Informazione, Universita di Trento, Via Sommarive, 14, I-38123 Povo di Trento (Italy); INFN, Sezione di Padova (Gruppo Collegato di Trento) (Italy); Giacomini, G.; Vianello, E.; Zorzi, N. [Fondazione Bruno Kessler, Centro per i Materiali e i Microsistemi (FBK-CMM), Via Sommarive, 18, I-38123 Povo di Trento (Italy)

2011-12-01

We report on the first batch of planar active edge sensors fabricated at Fondazione Bruno Kessler (Trento, Italy) on the way to the development of full 3D detectors with active edges. The main design and technological aspects are reported, along with selected results from the electrical characterization of detectors and test structures.

Magnesium borate radiothermoluminescent detectors

International Nuclear Information System (INIS)

Kazanskaya, V.A.; Kuzmin, V.V.; Minaeva, E.E.; Sokolov, A.D.

1974-01-01

In the report the technology of obtaining polycrystalline magnesium borate activated by dysprosium is described briefly and the method of preparing the tabletted detectors from it is presented. The dependence of the light sum of the samples on the proportion of the components and on the sintering regime has shown that the most sensitive material is obtained at the proportion of boric anhydride and magnesium oxide 2.2-2.4 and at the dysprosium concentration about 1 milligram-atom per gram molecule of the base. The glow curve of such a material has a simple form with one peak the maximum of which is located at 190-200 0 C. The measurement of the main dosimetric characteristics of the magnesium borate tabletted detectors and the comparison with similar parmaeters of the lithium fluoride tabletted detectors have shown that at practically identical effective number the former detectors have the following substantial advantages: the sensitivity is ten-twenty times as large, they are substantially more technological on synthesis of the radiothermoluminophor and during the production of the tabletted detectors, they have a simple glow curve, they do not require the utilization of the thermocycling during the use. (author)

Studying radiative B decays with the Atlas detector

International Nuclear Information System (INIS)

Viret, S.

2004-09-01

This thesis is dedicated to the study of radiative B decays with the ATLAS detector at the LHC (large hadron collider). Radiative decays belong to the rare decays family. Rare decays transitions involve flavor changing neutral currents (for example b → sγ), which are forbidden at the lowest order in the Standard Model. Therefore these processes occur only at the next order, thus involving penguin or box diagrams, which are very sensitive to 'new physics' contributions. The main goal of our study is to show that it would be possible to develop an online selection strategy for radiative B decays with the ATLAS detector. To this end, we have studied the treatment of low energy photons by the ATLAS electromagnetic calorimeter (ECal). Our analysis shows that ATLAS ECal will be efficient with these particles. This property is extensively used in the next section, where a selection strategy for radiative B decays is proposed. Indeed, we look for a low energy region of interest in the ECal as soon as the level 1 of the trigger. Then, photon identification cuts are performed in this region at level 2. However, a large part of the proposed selection scheme is also based on the inner detector, particularly at level 2. The final results show that large amounts of signal events could be collected in only one year by ATLAS. A preliminary significance (S/√B) estimation is also presented. Encouraging results concerning the observability of exclusive radiative B decays are obtained. (author)

The H1 detector

International Nuclear Information System (INIS)

Cozzika, G.

1992-11-01

The H1 detector presently operating at the HERA e-p collider is described. A general overview of the detector is given with particular emphasis on the calorimeters, the main element of which is a liquid Argon calorimeter enclosed within a large radius solenoid. Calorimetry in the proton direction, close to the beam-pipe is provided by a copper-silicon pad hadronic calorimeter. In the electron direction a lead-scintillator electromagnetic calorimeter closes the solid angle between the rear part of the liquid Argon calorimeter and the beam-pipe. An iron limited streamer tube tail catcher using the return yoke of the solenoid as absorber completes the calorimetry of the detector. The hardware triggers derived from the calorimeters are also described and some performance details of the calorimeters are given

The NA49 large acceptance hadron detector

International Nuclear Information System (INIS)

Afanasiev, S.; Alber, T.; Appelshaeuser, H.; Baechler, J.; Barna, D.; Barnby, L.S.; Bartke, J.; Barton, R.A.; Betev, L.; Bialkowska, H.; Bieser, F.; Billmeier, A.; Blyth, C.O.; Bock, R.; Bormann, C.; Bracinik, J.; Brady, F.P.; Brockmann, R.; Brun, R.; Buncic, P.; Caines, H.L.; Cebra, D.; Cooper, G.E.; Cramer, J.G.; Csato, P.; Cyprian, M.; Dunn, J.; Eckardt, V.; Eckhardt, F.; Empl, T.; Eschke, J.; Ferguson, M.I.; Fessler, H.; Fischer, H.G.; Flierl, D.; Fodor, Z.; Frankenfeld, U.; Foka, P.; Freund, P.; Friese, V.; Ftacnik, J.; Fuchs, M.; Gabler, F.; Gal, J.; Ganz, R.; Gazdzicki, M.; Gladysz, E.; Grebieszkow, J.; Guenther, J.; Harris, J.W.; Hegyi, S.; Henkel, T.; Hill, L.A.; Hlinka, V.; Huang, I.; Huemmler, H.; Igo, G.; Irmscher, D.; Ivanov, M.; Janik, R.; Jacobs, P.; Jones, P.G.; Kadija, K.; Kolesnikov, V.I.; Kowalski, M.; Lasiuk, B.; Levai, P.; Liebicher, K.; Lynen, U.; Malakhov, A.I.; Margetis, S.; Markert, C.; Marks, C.; Mayes, B.; Melkumov, G.L.; Mock, A.; Molnar, J.; Nelson, J.M.; Oldenburg, M.; Odyniec, G.; Palla, G.; Panagiotou, A.D.; Pestov, Y.; Petridis, A.; Pikna, M.; Pimpl, W.; Pinsky, L.; Piper, A.; Porter, R.J.; Poskanzer, A.M.; Poziombka, S.; Prindle, D.J.; Puehlhofer, F.; Rauch, W.; Reid, J.G.; Renfordt, R.; Retyk, W.; Ritter, H.G.; Roehrich, D.; Roland, C.; Roland, G.; Rudolph, H.; Rybicki, A.; Sammer, T.; Sandoval, A.; Sann, H.; Schaefer, E.; Schmidt, R.; Schmischke, D.; Schmitz, N.; Schoenfelder, S.; Semenov, A.Yu.; Seyboth, J.; Seyboth, P.; Seyerlein, J.; Sikler, F.; Sitar, B.; Skrzypczak, E.; Squier, G.T.A.; Stelzer, H.; Stock, R.; Strmen, P.; Stroebele, H.; Struck, C.; Susa, T.; Szarka, I.; Szentpetery, I.; Szymanski, P.; Sziklai, J.; Toy, M.; Trainor, T.A.; Trentalange, S.; Ullrich, T.; Vassiliou, M.; Veres, G.; Vesztergombi, G.; Vranic, D.; Wang, F.Q.; Weerasundara, D.D.; Wenig, S.; Whitten, C.; Wieman, H.; Wienold, T.; Wood, L.; Yates, T.A.; Zimanyi, J.; Zhu, X.-Z.; Zybert, R.

1999-01-01

The NA49 detector is a wide acceptance spectrometer for the study of hadron production in p+p, p+A, and A+A collisions at the CERN SPS. The main components are 4 large-volume TPCs for tracking and particle identification via dE/dx. TOF scintillator arrays complement particle identification. Calorimeters for transverse energy determination and triggering, a detector for centrality selection in p+A collisions, and beam definition detectors complete the set-up. A description of all detector components is given with emphasis on new technical realizations. Performance and operational experience are discussed in particular with respect to the high track density environment of central Pb+Pb collisions

The NA49 large acceptance hadron detector

CERN Document Server

Afanasiev, S V; Appelshäuser, H; Bächler, J; Barna, D; Barnby, L S; Bartke, Jerzy; Barton, R A; Betev, L; Bialkowska, H; Bieser, F; Billmeier, A; Blyth, C O; Böck, R K; Bormann, C; Bracinik, J; Brady, F P; Brockmann, R; Brun, R; Buncic, P; Caines, H L; Cebra, D; Cooper, G E; Cramer, J G; Csató, P; Cyprian, M; Dunn, J; Eckardt, V; Eckhardt, F; Empl, T; Eschke, J; Ferguson, M I; Fessler, H; Fischer, H G; Flierl, D; Fodor, Z; Frankenfeld, Ulrich; Foka, P Y; Freund, P; Friese, V; Ftácnik, J; Fuchs, M; Gabler, F; Gál, J; Ganz, R E; Gazdzicki, M; Gladysz-Dziadus, E; Grebieszkow, J; Günther, J; Harris, J W; Hegyi, S; Henkel, T; Hill, L A; Hlinka, V; Huang, I; Hümmler, H; Igo, G; Irmscher, D; Ivanov, M; Janik, R; Jacobs, P; Jones, P G; Kadija, K; Kolesnikov, V I; Kowalski, M; Lasiuk, B; Lévai, Peter; Liebicher, K; Lynen, U; Malakhov, A I; Margetis, S; Markert, C; Marks, C; Mayes, B W; Melkumov, G L; Mock, A; Molnár, J; Nelson, J M; Oldenburg, M; Odyniec, Grazyna Janina; Pálla, G; Panagiotou, A D; Pestov, Yu N; Petridis, A; Pikna, M; Pimpl, W; Pinsky, L; Piper, A; Porter, R J; Poskanzer, A M; Poziombka, S; Prindle, D J; Pühlhofer, F; Rauch, W; Reid, J G; Renfordt, R E; Retyk, W; Ritter, H G; Röhrich, D; Roland, C; Roland, G; Rudolph, H; Rybicki, A; Sammer, T; Sandoval, A; Sann, H; Schäfer, E; Schmidt, R; Schmischke, D; Schmitz, N; Schönfelder, S; Semenov, A Yu; Seyboth, J; Seyboth, P; Seyerlein, J; Siklér, F; Sitár, B; Skrzypczak, E; Squier, G T A; Stelzer, H; Stock, Reinhard; Strmen, P; Ströbele, H; Struck, C; Susa, T; Szarka, I; Szentpétery, I; Szymanski, P; Sziklai, J; Toy, M; Trainor, T A; Trentalange, S; Ullrich, T S; Vassiliou, Maria; Veres, G I; Vesztergombi, G; Vranic, D; Wang, F; Weerasundara, D D; Wenig, S; Whitten, C; Wieman, H H; Wienold, T; Wood, L; Yates, T A; Zimányi, J; Zhu, X Z; Zybert, R

1999-01-01

The NA49 detector is a wide acceptance spectrometer for the study of hadron production in p+p, p+A, and A+A collisions at the CERN SPS. The main components are 4 large volume TPCs for tracking and particle identification via $dE/dx$. TOF scintillator arrays complement particle identification. Calorimeters for transverse energy determination and triggering, a detector for centrality selection in p+A collisions, and beam definition detectors complete the set-up. A description of all detector components is given with emphasis on new technical realizations. Performance and operational experience are discussed in particular with respect to the high track density environment of central Pb+Pb collisions.

The ATLAS/TILECAL Detector Control System

CERN Document Server

Santos, H; The ATLAS collaboration

2010-01-01

Tilecal, the barrel hadronic calorimeter of ATLAS, is a sampling calorimeter where scintillating tiles are embedded in an iron matrix. The tiles are optically coupled to wavelength shifting fibers that carry the optical signal to photo-multipliers. It has a cylindrical shape and is made out of 3 cylinders, the Long Barrel with the LBA and LBC partitions, and the two Extended Barrel with the EBA and EBC partitions. The main task of the Tile calorimeter Detector Control System (DCS) is to enable the coherent and safe operation of the calorimeter. All actions initiated by the operator, as well as all errors, warnings and alarms concerning the hardware of the detector are handled by DCS. The Tile calorimeter DCS controls and monitors mainly the low voltage and high voltage power supply systems, but it is also interfaced with the infrastructure (cooling system and racks), the laser and cesium calibration systems, the data acquisition system, configuration and conditions databases and the detector safety system. In...

Search for Gamma-Ray Bursts with the ARGO-YBJ Detector in Shower Mode

Energy Technology Data Exchange (ETDEWEB)

Bartoli, B.; Catalanotti, S.; Piazzoli, B. D’Ettorre; Girolamo, T. Di [Dipartimento di Fisica dell’Universitá di Napoli “Federico II,” Complesso Universitario di Monte Sant’Angelo, via Cinthia, I-80126 Napoli (Italy); Bernardini, P.; D’Amone, A.; Mitri, I. De [Dipartimento Matematica e Fisica “Ennio De Giorgi,” Universitá del Salento, via per Arnesano, I-73100 Lecce (Italy); Bi, X. J.; Cao, Z.; Chen, S. Z.; Feng, Zhaoyang; Gao, W.; Gou, Q. B. [Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, P.O. Box 918, 100049 Beijing (China); Chen, T. L.; Danzengluobu [Tibet University, 850000 Lhasa, Xizang (China); Cui, S. W. [Hebei Normal University, 050024 Shijiazhuang Hebei (China); Dai, B. Z. [Yunnan University, 2 North Cuihu Road, 650091 Kunming, Yunnan (China); Sciascio, G. Di [Istituto Nazionale di Fisica Nucleare, Sezione di Roma Tor Vergata, via della Ricerca Scientifica 1, I-00133 Roma (Italy); Feng, C. F. [Shandong University, 250100 Jinan, Shandong (China); Feng, Zhenyong, E-mail: chensz@ihep.ac.cn, E-mail: zhouxx@swjtu.edu.cn [Southwest Jiaotong University, 610031 Chengdu, Sichuan (China); Collaboration: ARGO-YBJ Collaboration; and others

2017-06-10

The ARGO-YBJ detector, located at the Yangbajing Cosmic Ray Laboratory (4300 m a. s. l., Tibet, China), was a “full coverage” (central carpet with an active area of ∼93%) air shower array dedicated to gamma-ray astronomy and cosmic-ray studies. The wide field of view (∼2 sr) and high duty cycle (>86%), made ARGO-YBJ suitable to search for short and unexpected gamma-ray emissions like gamma-ray bursts (GRBs). Between 2007 November 6 and 2013 February 7, 156 satellite-triggered GRBs (24 of them with known redshift) occurred within the ARGO-YBJ field of view (zenith angle θ ≤ 45°). A search for possible emission associated with these GRBs has been made in the two energy ranges 10–100 GeV and 10–1000 GeV. No significant excess has been found in time coincidence with the satellite detections nor in a set of different time windows inside the interval of one hour after the bursts. Taking into account the EBL absorption, upper limits to the energy fluence at a 99% confidence level have been evaluated, with values ranging from ∼10{sup −5} erg cm{sup −2} to ∼10{sup −1} erg cm{sup −2}. The Fermi -GBM burst GRB 090902B, with a high-energy photon of 33.4 GeV detected by Fermi -LAT, is discussed in detail.

Fabrication of ATLAS pixel detector prototypes at IRST

International Nuclear Information System (INIS)

Boscardin, M.; Betta, G.-F. Dalla; Gregori, P.; Zen, M.; Zorzi, N.

2001-01-01

We report on the development of a fabrication technology for n-on-n silicon pixel detectors oriented to the ATLAS experiment at LHC. The main processing issues and some selected results from the electrical characterization of detector prototypes and related test structures are presented and discussed

Gravitational-wave detector realized by a superconductor

International Nuclear Information System (INIS)

Ishidoshiro, K.; Ando, M.; Takamori, A.; Okada, K.; Tsubono, K.

2010-01-01

In this article, we present a new gravitational-wave detector based on superconducting magnetic levitation and results of its prototype test. Our detector is composed of the suspended test mass that is rotated by gravitational waves. Gravitational wave signals are readout by monitoring its angular motion. Superconducting magnetic levitation is used for the suspension of the test mass, since it has many advantages, such as zero mechanical loss and resonant frequency around its suspension axis in an ideal situation. For the study of actual performance of such gravitational-wave detector, a prototype detector has been developed. Using the prototype detector, the actual loss factor and resonant frequency are measured as 1.2 x 10 -8 Nms/rad and 5 mHz respectively. A detector noise is also evaluated. The current noise level is determined by the magnetic coupling with external magnetic field and mechanical coupling between translation and angular motion. The prototype detector has already one of the lowest noise levels for gravitational waves at 0.1 Hz among current gravitational-wave detectors. We have succeeded at the demonstration of the advantages of our torsion gravitational-wave detector.

Mechanics and cooling of the Mu3e detector

Energy Technology Data Exchange (ETDEWEB)

Austermuehl, Rene Philipp; Henkelmann, Lars; Herkert, Adrian; Ng, Yanwing [Physikalisches Institut, Uni Heidelberg (Germany); Collaboration: Mu3e-Collaboration

2016-07-01

The Mu3e experiment will search for the charged lepton flavour violating decay μ{sup +} → e{sup +}e{sup -}e{sup +}, which is suppressed to unobservable levels in the Standard Model. A signal would be a clear sign of new physics. The aim is to reach a sensitivity for the branching ratio of 10{sup -16}, which requires high momentum resolution. Since the muons will decay at rest on target, the energy of the decay electrons will be E≤53 MeV. In this energy regime the momentum resolution is limited by multiple scattering in the detector material. Therefore, the Mu3e detector, including support structure and services, has to consist of as little material as possible in the active region. The main component of the detector is a pixel tracker consisting of four barrels of high voltage monolithic active pixel sensors (HV-MAPS) that can be thinned to 50 μm. A power consumption of 400 mW/cm{sup 2} is expected. To keep the material budget low, it is planned to cool with gaseous helium. In this talk results of computational fluid dynamics simulations of the Mu3e cooling system and experimental tests concerning the detector's stability against flow-induced vibrations are presented.

Detectors and Concepts for sub-100 ps timing with gaseous detectors

CERN Document Server

Gonzalez-Diaz, D.

2017-01-01

We give a short compendium of the main ongoing detectors and concepts capable of performing accurate sub-100 ps timing at high particle fluxes and on large areas, through technologies based on gaseous media. We briefly discuss the state-of-the-art, technological limitations and prospects, and a new bizarre idea.

The Tilecal/ATLAS detector control system

CERN Document Server

Tomasio Pina, João Antonio

2004-01-01

Tilecal is the barrel hadronic calorimeter of the ATLAS detector that is presently being built at CERN to operate at the LHC accelerator. The main task of the Tilecal detector control system (DCS) is to enable the coherent and safe operation of the detector. All actions initiated by the operator and all errors, warnings, and alarms concerning the hardware of the detector are handled by DCS. The DCS has to continuously monitor all operational parameters, give warnings and alarms concerning the hardware of the detector. The DCS architecture consists of a distributed back-end (BE) system running on PC's and different front-end (FE) systems. The implementation of the BE will he achieved with a commercial supervisory control and data acquisition system (SCADA) and the FE instrumentation will consist on a wide variety of equipment. The connection between the FE and BE is provided by fieldbus or L

Adaptive Multiuser Detectors for DS-CDMA Systems

Directory of Open Access Journals (Sweden)

Paul Jean Etienne Jeszensky

2006-02-01

Full Text Available This work makes a review of the main Adaptives Multi-user Detectors (MuD-Adpt for Direct Sequence - Code Division Multiple Access (DS-CDMA systems. The MuD-Adpt based on Minimum Mean Square Error (MMSE and Decorrelator (MuD-Dec are focused. Multi-user detectors show great resistance to the near-far effect and combat effectively the Multiple Access Interference (MAI. Comparative numeric results characterize the substantial performance improvement of those detectors in relation to the matched filter conventional receiver (Conv.

Micro-channel cooling for silicon detectors

Energy Technology Data Exchange (ETDEWEB)

Flaschel, Nils

2017-12-15

Silicon tracking detectors employed in high-energy physics are located very close to the interaction points of the colliding particle beams. The high energetic radiation emerging from the interaction induces defects into the silicon, downgrading the efficiency to collect the charges created by passing particles and increasing the noise while data taking. Cooling the sensors to low temperatures can help to prevent defects and maintain a high efficiency and lower noise level. In order to maximize the LHC's discovery potential, the collider and its detectors will be upgraded to a higher luminosity around 2024. The conditions inside the detector will become harsher demanding that the technology must adapt to the new situation. Radiation damage is already an issue in the current ATLAS detector and therefore a huge number of parameters are constantly monitored and evaluated to ensure optimal operation. To provide the best possible settings the behavior of the sensors inside the ATLAS Inner Detector is predicted using simulations. In this work several parameters in the simulation including the depletion voltage and the crosstalk between sensor strips of the SCT detector are analyzed and compared with data. The main part of this work concerns the investigation of a novel cooling system based on microchannels etched into silicon in a generic research and development project at DESY and IMB-CNM. A channel layout is designed providing a homogeneous flow distribution across a large surface area and tested in a computational fluid simulation before its production. Two different fabrication techniques, anodic and eutectic bonding, are used to test prototypes with differing mechanical and thermal properties. Hydromechanical and thermal measurements are performed to fully characterize the flow inside the device and the thermal properties of the prototype in air and in a vacuum. The thermal behavior is analyzed by means of local measurements with thermal resistors and infrared

Micro-channel cooling for silicon detectors

International Nuclear Information System (INIS)

Flaschel, Nils

2017-12-01

Silicon tracking detectors employed in high-energy physics are located very close to the interaction points of the colliding particle beams. The high energetic radiation emerging from the interaction induces defects into the silicon, downgrading the efficiency to collect the charges created by passing particles and increasing the noise while data taking. Cooling the sensors to low temperatures can help to prevent defects and maintain a high efficiency and lower noise level. In order to maximize the LHC's discovery potential, the collider and its detectors will be upgraded to a higher luminosity around 2024. The conditions inside the detector will become harsher demanding that the technology must adapt to the new situation. Radiation damage is already an issue in the current ATLAS detector and therefore a huge number of parameters are constantly monitored and evaluated to ensure optimal operation. To provide the best possible settings the behavior of the sensors inside the ATLAS Inner Detector is predicted using simulations. In this work several parameters in the simulation including the depletion voltage and the crosstalk between sensor strips of the SCT detector are analyzed and compared with data. The main part of this work concerns the investigation of a novel cooling system based on microchannels etched into silicon in a generic research and development project at DESY and IMB-CNM. A channel layout is designed providing a homogeneous flow distribution across a large surface area and tested in a computational fluid simulation before its production. Two different fabrication techniques, anodic and eutectic bonding, are used to test prototypes with differing mechanical and thermal properties. Hydromechanical and thermal measurements are performed to fully characterize the flow inside the device and the thermal properties of the prototype in air and in a vacuum. The thermal behavior is analyzed by means of local measurements with thermal resistors and infrared

Detectors - Electronics; Detecteurs - Electronique

Energy Technology Data Exchange (ETDEWEB)

Bregeault, J.; Gabriel, J.L.; Hierle, G.; Lebotlan, P.; Leconte, A.; Lelandais, J.; Mosrin, P.; Munsch, P.; Saur, H.; Tillier, J. [Lab. de Physique Corpusculaire, Caen Univ., 14 (France)

1998-04-01

The reports presents the main results obtained in the fields of radiation detectors and associated electronics. In the domain of X-ray gas detectors for the keV range efforts were undertaken to rise the detector efficiency. Multiple gap parallel plate chambers of different types as well as different types of X {yields} e{sup -} converters were tested to improve the efficiency (values of 2.4% at 60 KeV were reached). In the field of scintillators a study of new crystals has been carried out (among which Lutetium orthosilicate). CdTe diode strips for obtaining X-ray imaging were studied. The complete study of a linear array of 8 CdTe pixels has been performed and certified. The results are encouraging and point to this method as a satisfying solution. Also, a large dimension programmable chamber was used to study the influence of temperature on the inorganic scintillators in an interval from -40 deg. C to +150 deg. C. Temperature effects on other detectors and electronic circuits were also investigated. In the report mentioned is also the work carried out for the realization of the DEMON neutron multidetector. For neutron halo experiments different large area Si detectors associated with solid and gas position detectors were realized. In the frame of a contract with COGEMA a systematic study of Li doped glasses was undertaken aiming at replacing with a neutron probe the {sup 3}He counters presently utilized in pollution monitoring. An industrial prototype has been realised. Other studies were related to integrated analog chains, materials for Cherenkov detectors, scintillation probes for experiments on fundamental processes, gas position sensitive detectors, etc. In the field of associated electronics there are mentioned the works related to the multidetector INDRA, data acquisition, software gamma spectrometry, automatic gas pressure regulation in detectors, etc

Development of sodium leak detectors for PFBR

International Nuclear Information System (INIS)

Sylvia, J.I.; Rao, P. Vijayamohana; Babu, B.; Madhusoodanan, K.; Rajan, K.K.

2012-01-01

Highlights: ► Sodium leak detection system developed for PFBR using diverse principle. ► Miniature, remotely locatable diverse leak detector developed for Main Vessel. ► Mutual inductance type leak detectors designed and adapted for different locations. ► Sodium Ionisation detectors used for area monitoring. ► Crosswire type leak detector designed, developed and tested. - Abstract: The 500 MWe Prototype Fast Breeder Reactor (PFBR) is under advanced stage of construction at Kalpakkam near Chennai in India. The wide and high operating temperature, highly chemically active nature of sodium and its reaction with air make the sodium instrumentation complex over the conventional instrumentation. Over the years, traditional instruments such as wire type leak detectors, spark plug type leak detectors were developed and used in different sodium systems. The redundant and diverse leak detection method calls for development of special instrumentation for sodium systems which include sodium ionization (leak) detector for detecting minute sodium leak in addition to those systems based on mutual inductance principle. For detection of sodium leak from reactor Main Vessel (MV), diverse methods are used such as miniature, remotely locatable, Mutual Inductance type Leak Detector(MILD) and specially modified spark plug type leak detector. The design of MILD is suitably modified for detecting leak in double wall pipes and Diverse Safety Rod drive Mechanism (DSRDM). Steam/water leak in steam generator produces hydrogen and leads to high pressure and temperature in the system. Rupture disc is used as a safety device which punctures itself due to sudden pressure rise. To detect the discharge of sodium and its reaction products at the downstream of the rupture disc due to bursting of the rupture disc, cross wire type leak detector has been designed, developed and tested. The selection of the leak detection system depends on the location where leak has to be detected. This paper

Solid state nuclear track detectors

International Nuclear Information System (INIS)

Medeiros, J.A.; Carvalho, M.L.C.P. de

1992-12-01

Solid state nuclear track detectors (SSNTD) are dielectric materials, crystalline or vitreous, which registers tracks of charged nuclear particles, like alpha particles or fission fragments. Chemical etching of the detectors origin tracks that are visible at the optical microscope: track etching rate is higher along the latent track, where damage due to the charged particle increase the chemical potential, and etching rate giving rise to holes, the etched tracks. Fundamental principles are presented as well as some ideas of main applications. (author)

Superconductive tunnel structures as radiation detectors

International Nuclear Information System (INIS)

Barone, A.; Gray, K.E.

1985-08-01

A brief review is given on various aspects of the potential of superconducting tunnel junctions as detectors for atomic and nuclear radiations. On the basis of recent results main advantages and drawbacks are indicated providing a preliminary comparison with the presently used semiconductor detectors. The basic ideas underlying the physics of the interaction of nuclear particles and other radiations with superconducting junctions are outlined. 9 refs., 1 tab

Solid state detectors for neutron radiation monitoring in fusion facilities

International Nuclear Information System (INIS)

Gómez-Ros, J.M.

2014-01-01

The purpose of this communication is to summarize the main solid state based detectors proposed for neutron diagnostic in fusion applications and their applicability under the required harsh conditions in terms of intense radiation, high temperature and available space restrictions. Activation systems, semiconductor based detectors, luminescent materials and Cerenkov fibre optics sensors (C-FOS) are the main devices that are described. - Highlights: • A state-of-the-art summary of solid state based detectors are described. • Conditions and restrictions for their applicability are described. • A list of the 38 more relevant references has been included

The STAR Vertex Position Detector

Energy Technology Data Exchange (ETDEWEB)

Llope, W.J., E-mail: llope@rice.edu [Rice University, Houston, TX 77005 (United States); Zhou, J.; Nussbaum, T. [Rice University, Houston, TX 77005 (United States); Hoffmann, G.W. [University of Texas, Austin, TX 78712 (United States); Asselta, K. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Brandenburg, J.D.; Butterworth, J. [Rice University, Houston, TX 77005 (United States); Camarda, T.; Christie, W. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Crawford, H.J. [University of California, Berkeley, CA 94720 (United States); Dong, X. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Engelage, J. [University of California, Berkeley, CA 94720 (United States); Eppley, G.; Geurts, F. [Rice University, Houston, TX 77005 (United States); Hammond, J. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Judd, E. [University of California, Berkeley, CA 94720 (United States); McDonald, D.L. [Rice University, Houston, TX 77005 (United States); Perkins, C. [University of California, Berkeley, CA 94720 (United States); Ruan, L.; Scheblein, J. [Brookhaven National Laboratory, Upton, NY 11973 (United States); and others

2014-09-21

The 2×3 channel pseudo Vertex Position Detector (pVPD) in the STAR experiment at RHIC has been upgraded to a 2×19 channel detector in the same acceptance, called the Vertex Position Detector (VPD). This detector is fully integrated into the STAR trigger system and provides the primary input to the minimum-bias trigger in Au+Au collisions. The information from the detector is used both in the STAR Level-0 trigger and offline to measure the location of the primary collision vertex along the beam pipe and the event “start time” needed by other fast-timing detectors in STAR. The offline timing resolution of single detector channels in full-energy Au+Au collisions is ∼100 ps, resulting in a start time resolution of a few tens of picoseconds and a resolution on the primary vertex location of ∼1 cm.

Radiation damage in silicon. Defect analysis and detector properties

Energy Technology Data Exchange (ETDEWEB)

Hoenniger, F.

2008-01-15

Silicon microstrip and pixel detectors are vital sensor-components as particle tracking detectors for present as well as future high-energy physics (HEP) experiments. All experiments at the large Hadron Collider (LHC) are equipped with such detectors. Also for experiments after the upgrade of the LHC (the so-called Super-LHC), with its ten times higher luminosity, or the planned International Linear Collider (ILC) silicon tracking detectors are forseen. Close to the interaction region these detectors have to face harsh radiation fields with intensities above the presently tolerable level. defect engineering of the used material, e. g. oxygen enrichment of high resistivity float zone silicon and growing of thin low resistivityepitaxial layers on Czochralski silicon substrates has been established to improve the radiation hardness of silicon sensors. This thesis focuses mainly on the investigation of radiation induced defects and their differences observed in various kinds of epitaxial silicon material. Comparisons with other materials like float zone or Czochralski silicon are added. Deep Level Transient Spectroscopy (DLTS) and Thermally Stimulated Current (TSC) measurements have been performed after {gamma}-, electron-, proton- and neutron-irradiation. The differenced in the formation of vacancy and interstitial related defects as well as so-called clustered regions were investigated for various types of irradiation. In addition to the well known defects VO{sub i}, C{sub i}O{sub i}, C{sub i}C{sub s}, VP or V{sub 2} several other defect complexes have been found and investigated. Also the material dependence of the defect introduction rates and the defect annealing behavior has been studied by isothermal and isochronal annealing experiments. Especially the IO{sub 2} defect which is an indicator for the oxygen-dimer content of the material has been investigated in detail. On the basis of radiation induced defects like the bistable donor (BD) defect and a deep

Radiation damage in silicon. Defect analysis and detector properties

International Nuclear Information System (INIS)

Hoenniger, F.

2008-01-01

Silicon microstrip and pixel detectors are vital sensor-components as particle tracking detectors for present as well as future high-energy physics (HEP) experiments. All experiments at the large Hadron Collider (LHC) are equipped with such detectors. Also for experiments after the upgrade of the LHC (the so-called Super-LHC), with its ten times higher luminosity, or the planned International Linear Collider (ILC) silicon tracking detectors are forseen. Close to the interaction region these detectors have to face harsh radiation fields with intensities above the presently tolerable level. defect engineering of the used material, e. g. oxygen enrichment of high resistivity float zone silicon and growing of thin low resistivityepitaxial layers on Czochralski silicon substrates has been established to improve the radiation hardness of silicon sensors. This thesis focuses mainly on the investigation of radiation induced defects and their differences observed in various kinds of epitaxial silicon material. Comparisons with other materials like float zone or Czochralski silicon are added. Deep Level Transient Spectroscopy (DLTS) and Thermally Stimulated Current (TSC) measurements have been performed after γ-, electron-, proton- and neutron-irradiation. The differenced in the formation of vacancy and interstitial related defects as well as so-called clustered regions were investigated for various types of irradiation. In addition to the well known defects VO i , C i O i , C i C s , VP or V 2 several other defect complexes have been found and investigated. Also the material dependence of the defect introduction rates and the defect annealing behavior has been studied by isothermal and isochronal annealing experiments. Especially the IO 2 defect which is an indicator for the oxygen-dimer content of the material has been investigated in detail. On the basis of radiation induced defects like the bistable donor (BD) defect and a deep acceptor, a model has been introduced to

LEVEL-1 DATA DRIVER CARD - A high bandwidth radiation tolerant aggregator board for detectors

CERN Document Server

Gkountoumis, Panagiotis; The ATLAS collaboration

2018-01-01

The Level-1 Data Driver Card (L1DDC) was designed for the needs of the future upgrades of the innermost stations of the ATLAS end-cap muon spectrometer. The detectors located at the muon Small Wheels will be replaced by a set of precision tracking and trigger detectors, the resistive Micromegas (MM) and the small-strip Thin Gap Chambers (sTGC). After the upgrade, the number of interactions per bunch-crossing will be increased up to 140, resulting in a dramatically large amount of produced data. The high number of electronic channels (about two million for the MM and about 300k for the sTGC) along with a harsh environment (radiation dose up to 1700Gy (inner radius) and a magnetic field up to 0:4T in the end cap region) led to the development of new radiation tolerant electronics and a scalable readout scheme able to handle the new data rates. In addition, correction mechanisms for Single Event Upsets (SEU) and communication errors must be implemented to assure the integrity of the transmitted data. The L1DDC i...

Comparison of Detector Technologies for CAPS

Science.gov (United States)

Stockum, Jana L.

2005-01-01

In this paper, several different detectors are examined for use in a Comet/Asteroid Protection System (CAPS), a conceptual study for a possible future space-based system. Each detector will be examined for its future (25 years or more in the future) ability to find and track near-Earth Objects (NEOs) from a space-based detection platform. Within the CAPS study are several teams of people who each focus on different aspects of the system concept. This study s focus is on detection devices. In particular, evaluations on the following devices have been made: charge-coupled devices (CCDs), charge-injected devices (CIDs), superconducting tunneling junctions (STJs), and transition edge sensors (TESs). These devices can be separated into two main categories; the first category includes detectors that are currently being widely utilized, such as CCDs and CIDs. The second category includes experimental detectors, such as STJs and TESs. After the discussion of the detectors themselves, there will be a section devoted to the explicit use of these detectors with CAPS.

Water level sensor and temperature profile detector

Science.gov (United States)

Tokarz, Richard D.

1983-01-01

A temperature profile detector comprising a surrounding length of metal tubing and an interior electrical conductor both constructed of high temperature high electrical resistance materials. A plurality of gas-filled expandable bellows made of electrically conductive material is electrically connected to the interior electrical conductor and positioned within the length of metal tubing. The bellows are sealed and contain a predetermined volume of a gas designed to effect movement of the bellows from an open circuit condition to a closed circuit condition in response to monitored temperature changes sensed by each bellows.

Water-level sensor and temperature-profile detector

Science.gov (United States)

Not Available

1981-01-29

A temperature profile detector is described which comprises a surrounding length of metal tubing and an interior electrical conductor both constructed of high temperature high electrical resistance materials. A plurality of gas-filled expandable bellows made of electrically conductive material are positioned at spaced locations along a length of the conductors. The bellows are sealed and contain a predetermined volume of a gas designed to effect movement of the bellows from an open circuit condition to a closed circuit condition in response to monitored temperature changes sensed by each bellows.

Water level sensor and temperature profile detector

International Nuclear Information System (INIS)

Tokarz, R.D.

1983-01-01

A temperature profile detector comprising a surrounding length of metal tubing and an interior electrical conductor both constructed of high temperature high electrical resistance materials. A plurality of gas-filled expandable bellows made of electrically conductive material is electrically connected to the interior electrical conductor and positioned within the length of metal tubing. The bellows are sealed and contain a predetermined volume of a gas designed to effect movement of the bellows from an open circuit condition to a closed circuit condition in response to monitored temperature changes sensed by each bellows

ALICE Transition Radiation Detector

CERN Multimedia

Pachmayer, Y

2013-01-01

The Transition Radiation Detector (TRD) is the main electron detector in ALICE. In conduction with the TPC and the ITS, it provides the necessary electron identification capability to study: - Production of light and heavy vector mesons as well as the continuum in the di-electron channel, - Semi leptonic decays of hadrons with open charm and open beauty via the single-electron channel using the displaced vertex information provided by the ITS, - Correlated DD and BB pairs via coincidences of electrons in the central barrel and muons in the forward muon arm, - Jets with high Pτ tracks in one single TRD stack.

Development of nuclear track detectors

International Nuclear Information System (INIS)

Somogyi, Gyoergy

1985-01-01

The birth and development of two decades of a new nuclear detection method is briefly summarized by one of the first inventors. The main steps of the development and broadening application of nuclear solid state track detectors are described underlying the contribution and main results of the research group of ATOMKI, Hungary (i.e. the finding of the proper plastic materials for track detectors, the discovery of correlations between the track diameter and the particle energy, the increasing of energy resolution, explanation of the track developing process, elaboration of new electrochemical track analyzing methods and automatic track analyzers). Recently, this detecting technique has grown to the phase of the industrial mass production and broad application in radiogeochemistry, mining, radioecology, personal monitoring in nuclear power plants, etc. (D.Gy.)

Detector Control and Data Acquisition for the Wide-Field Infrared Survey Telescope (WFIRST) with a Custom ASIC

Science.gov (United States)

Smith, Brian S.; Loose, Markus; Alkire, Greg; Joshi, Atul; Kelly, Daniel; Siskind, Eric; Rossetti, Dino; Mah, Jonathan; Cheng, Edward; Miko, Laddawan;

Development of a multichannel RF field detector for the low-level RF control of the free-electron laser at Hamburg

International Nuclear Information System (INIS)

Hoffmann, Matthias

2008-10-01

Modern free electron lasers produce synchrotron radiation with constantly shortening wavelengths of up to 6 nm and pulse widths of up to 100 fs. That requires a constantly increasing stability of the beam energy and arrival time of the electron beam at the undulator entrance which is situated at the end of the accelerator. At the same time, the increasing speed of digital signal processing and data acquisition facilitates new possibilities for the digital radio frequency control and field detection. In this thesis the development of a multichannel radio frequency field detector for the low level radio frequency (LLRF) control of the superconducting cavities of the Free-Electron Laser at Hamburg (FLASH) is described. The applied method of IF sampling is state of the technology and is utilized in many areas of digital communication. It is evaluated concerning its applicability for the LLRF control. Analytical and numerical investigations of the noise behavior and transport in the control loop have been accomplished to define the requirements for the measurement accuracy of the field detector that was to be developed. Therefore, simplified models of the noise behavior of each system component of the control loop, e.g. amplifier, radio frequency mixer and analog-to-digital converter, were established and subsequently assorted to a the model of the control loop. Due to the application of the vector-sum control, where several separately measured field vectors are added to a vector-sum, requirements concerning the allowable compression error of the detector nonlinearity were defined. These were investigated by analytical and numerical methods, as well. Requirements for the hardware that was to be developed were compiled from the simulation results. For the development of the field detector, a modular and EMC-compatible concept with a high-level passive front-end for an improvement of the signal-to-noise ratio was chosen. The following tests in the lab delivered the

Development of a multichannel RF field detector for the low-level RF control of the free-electron laser at Hamburg

Energy Technology Data Exchange (ETDEWEB)

Hoffmann, Matthias

2008-10-15

Modern free electron lasers produce synchrotron radiation with constantly shortening wavelengths of up to 6 nm and pulse widths of up to 100 fs. That requires a constantly increasing stability of the beam energy and arrival time of the electron beam at the undulator entrance which is situated at the end of the accelerator. At the same time, the increasing speed of digital signal processing and data acquisition facilitates new possibilities for the digital radio frequency control and field detection. In this thesis the development of a multichannel radio frequency field detector for the low level radio frequency (LLRF) control of the superconducting cavities of the Free-Electron Laser at Hamburg (FLASH) is described. The applied method of IF sampling is state of the technology and is utilized in many areas of digital communication. It is evaluated concerning its applicability for the LLRF control. Analytical and numerical investigations of the noise behavior and transport in the control loop have been accomplished to define the requirements for the measurement accuracy of the field detector that was to be developed. Therefore, simplified models of the noise behavior of each system component of the control loop, e.g. amplifier, radio frequency mixer and analog-to-digital converter, were established and subsequently assorted to a the model of the control loop. Due to the application of the vector-sum control, where several separately measured field vectors are added to a vector-sum, requirements concerning the allowable compression error of the detector nonlinearity were defined. These were investigated by analytical and numerical methods, as well. Requirements for the hardware that was to be developed were compiled from the simulation results. For the development of the field detector, a modular and EMC-compatible concept with a high-level passive front-end for an improvement of the signal-to-noise ratio was chosen. The following tests in the lab delivered the

Recent upgrades and performance of the CACTUS detector array

International Nuclear Information System (INIS)

Schiller, A.; Bergholt, L.; Guttormsen, M.

1998-03-01

The SCANDITRONIX MC-35 cyclotron laboratory, including the Oslo Cyclotron, has been in operation since 1980. The main auxiliary equipment consists of the multi-detector system CACTUS. During the last years, new, high efficiency Ge(HP) detectors were purchased and integrated in the CACTUS detector array. In this connection, the electronical setup was revised and altered. Several drawbacks of the old setup could be pointed out and eliminated. A test of the performance of all detector array elements was made with high accuracy. 27 refs

Scintillation neutron detector with dynamic threshold

International Nuclear Information System (INIS)

Kornilov, N.; Massey, T.; Grimes, S.

2014-01-01

Scintillation neutron detectors with hydrogen are a common tool for neutron spectroscopy. They provide good time resolution, neutron-gamma discrimination and high efficiency of neutron counting. The real open problems connected with application of these detectors are in the energy range >10 MeV. There are no standard neutron spectra known with high accuracy for this energy range. Therefore, traditional methods for experimental investigation of the efficiency function fail for these neutrons. The Monte Carlo simulation cannot provide reasonable accuracy due to unknown characteristics of the reactions for charged particle production (p, α and so on, light output, reaction cross-sections). The application of fission chamber with fissile material as a neutron detector did not help to solve the problem. We may avoid many problems if we use the traditional neutron detector with non-traditional data analysis. In this report we give main relations, and demonstrate the method for Cf-source. Experimental detector efficiency is compared with MC simulation. (authors)

Detectors plans for LS1

International Nuclear Information System (INIS)

Nessi, M.

2012-01-01

All experiments plan an effective usage of the LS1 shutdown period. After three years of running they will go through a consolidation phase, mostly to fix problems that have emerged over time, like single points of failure in the infrastructure, failures of low-voltage power supplies and optical links. Upgrades of some detector components will start, mainly related to the beam pipe, the innermost tracker elements and the trigger system. Detector components, which had to be staged for cost reasons in 2003, will then enter into the detector setup. The goal is to be fully ready for the new energy regime at nominal luminosity. This article reviews the planned maintenance and modification works for ATLAS, CMS, LHCb and ALICE experiments. (author)

A Comparison between HPGe and NaI(Tl) detectors performance for gamma-spectrometry of low level measurement

International Nuclear Information System (INIS)

Poursiamy, N. H.; Tajikahmadi, H.; Mirshojaei, S. F.

2005-01-01

According to progressive usage of nuclear technology, it's important to prevent the contamination of the environment by man-made radioisotopes and exposures of human being. Radioisotopes can enter the human body by inhalation and ingestion which are the most important ways to internal exposures. Measurement of radiation level in foodstuff is one of the most important parameters in environmental safety which is performed according to constitution and standard tests in most countries such as Iran. Gamma spectrometry is carried out by NaI(Tl) and HPGe detector systems for foodstuffs. In this research operation of HPGe and NaI(Tl) detectors in gamma spectrometry with a standard radioactive source are investigated and compared. Also the result of NaI superiority in foodstuff radiation measurement given

Measurement of ionising radiation semiconductor detectors: a review

International Nuclear Information System (INIS)

Aussel, J.P.

1986-06-01

Manufacturing techniques for nuclear detectors using semiconductors are constantly advancing, and a large range of models with different specificities and characteristics are available. After a theoretical reminder, this report describes the main types of detectors, their working and their preferential use. A comparative table guides the neophyte reader in his choice [fr

RID-41 gamma flaw detector

International Nuclear Information System (INIS)

Glebov, V.N.; Zubkov, V.S.; Majorov, A.N.; Murashev, A.I.; Firstov, V.G.; Yampol'skij, V.V.; Goncharov, V.I.; Sakhanov, A.S.

1978-01-01

The design is described and the main characteristics are given of a universal stationary hose-type gamma flow detector with a 60 Co source from 3O to 4g0 Ci for high-productive control of thick-walled products from steel and other materials. The principal units of the instrument are a radiation head, a control panel, and a charge-exchange container. The flaw detector may be used both in shield chambers and in shop or mounting conditions on complying with due requirements of radiation protection. The high activity of the source at relatively small dimensions of its active part ensures good detection of defects. The high radioscopy rate permits to use the flaw detector in conditions of increased background radiation, e.g. during routine repairs and inspections at nuclear power plants. The instrument may also be used in radiometric complexes, and produces a considerable economic effect. This flaw-detector corresponds to ISO and IAEA requirements and may be delivered for export

Modeling the Efficiency of a Germanium Detector

Science.gov (United States)

Hayton, Keith; Prewitt, Michelle; Quarles, C. A.

2006-10-01

We are using the Monte Carlo Program PENELOPE and the cylindrical geometry program PENCYL to develop a model of the detector efficiency of a planar Ge detector. The detector is used for x-ray measurements in an ongoing experiment to measure electron bremsstrahlung. While we are mainly interested in the efficiency up to 60 keV, the model ranges from 10.1 keV (below the Ge absorption edge at 11.1 keV) to 800 keV. Measurements of the detector efficiency have been made in a well-defined geometry with calibrated radioactive sources: Co-57, Se-75, Ba-133, Am-241 and Bi-207. The model is compared with the experimental measurements and is expected to provide a better interpolation formula for the detector efficiency than simply using x-ray absorption coefficients for the major constituents of the detector. Using PENELOPE, we will discuss several factors, such as Ge dead layer, surface ice layer and angular divergence of the source, that influence the efficiency of the detector.

α-spectra hyperfine structure resolution by silicon planar detectors

International Nuclear Information System (INIS)

Eremin, V.K.; Verbitskaya, E.M.; Strokan, N.B.; Sukhanov, V.L.; Malyarenko, A.M.

1986-01-01

The lines with 13 keV step from the main one is α-spectra of nuclei with an odd number of nucleons take place. Silicon planar detectors n-Si with the operation surface of 10 mm 2 are developed for resolution of this hyperfine structure. The mechanism of losses in detectors for short-range-path particles is analyzed. The results of measurements from detectors with 10 keV resolution are presented

Natural radioactivity level of main building materials in Baotou, China

International Nuclear Information System (INIS)

Zhao Caifeng; Lu Xinwei; Li Nan; Yang Guang

2012-01-01

A survey was done on natural radioactivity level and annual effective dose rate of main building materials in Baotou, China. The natural radionuclides of 40 K, 232 Th and 226 Ra in main building materials collected from Baotou were measured using NaI γ-ray spectrometry and the measured data were analyzed according to the national standards and radiological protection principles of the European Commission. The specific activities of 40 K, 232 Th and 226 Ra in the building materials samples were 218.82-1145.92, 19.75-1.32.50 and 11.46-82.66 Bq/kg, respectively. The internal and external exposure indexes of building materials were 0.06-0.41 and 0.28-0.70, respectively. The annual effective dose equivalent was 0.41-0.97 mSv/y. This justifies the production and sale of the main building materials, as both the internal and external exposure indexes of building materials are less than 1. The effective dose rate of ash brick is 0.97 mSv/y, while the maximum acceptable value is 1 mSv/y. Therefore, it is necessary to control the amount of industrial waste residue in building materials to avoid unnecessary radioactive exposure to residents. (authors)

Development of high efficiency neutron detectors

International Nuclear Information System (INIS)

Pickrell, M.M.; Menlove, H.O.

1993-01-01

The authors have designed a novel neutron detector system using conventional 3 He detector tubes and composites of polyethylene and graphite. At this time the design consists entirely of MCNP simulations of different detector configurations and materials. These detectors are applicable to low-level passive and active neutron assay systems such as the passive add-a-source and the 252 Cf shuffler. Monte Carlo simulations of these neutron detector designs achieved efficiencies of over 35% for assay chambers that can accommodate 55-gal. drums. Only slight increases in the number of detector tubes and helium pressure are required. The detectors also have reduced die-away times. Potential applications are coincident and multiplicity neutron counting for waste disposal and safeguards. The authors will present the general design philosophy, underlying physics, calculation mechanics, and results

Process allowing the spectral compensation of semi-conductor nuclear detector

International Nuclear Information System (INIS)

L'Hote, J.P.

1987-01-01

The process includes a discriminator whose threshold level is applied to the detector during a fixed time and is externally controlled by a pre-programmed system; the different threshold levels and their application time to the detector are fixed by the nature of the used detector and by the tolerance allowed on the spectral response. The measurements made for each threshold level are corrected by a coefficient depending on the nature of the used detector and the tolerance on the spectral response [fr

Construction of a self-powered neutron detector prototype

International Nuclear Information System (INIS)

Pombo, J.B.S.M.; Correa, R.F.

1986-01-01

Description and testing of a self-powered neutron detector and related current measurement electronics, in construction at Centro de Desenvolviemnto da Tecnologia Nuclear (CDTN), are presented. The cylindrical detector has a 9-wires cobalt emitter, Inconel 600 tubing collector and sinterized alumina electrical insulation. The bifilar signal cable is plugged to the detector through a SHV connector. Preliminary testing has giving information about dielectrical properties of the set and impurities of the materials (by means of activation analysis). The main tests, done in a 100 KW Triga Reactor, allowed the verification of the detector response to the neutron flux, the stability and reproducibility of this response, and also the evaluation of sensitivity to gamma radiation. The detector performance is considered good. (Author) [pt

ArgonCube: a Modular Approach for Liquid Argon TPC Neutrino Detectors for Near Detector Environments

CERN Document Server

Auger, M; Sinclair, JR

2017-01-01

Liquid Argon Time Projection Chambers (LAr TPCs) are an ideal detector candidate for future neutrino oscillation physics experiments, underground neutrino observatories and proton decay searches. A large international project based on this technology is currently under consideration at the future LBNF/DUNE facility in the United States. That particular endeavor would be on the very large mass scale of 40~kt. Following diverse and long standing R\\&D work conducted over several years, with contributions from international collaborators, we propose a novel LAr TPC based on a fully-modular, innovative design, ArgonCube. ArgonCube will demonstrate that LAr TPCs are a viable detector technology for high-energy and high-multiplicity environments, such as the DUNE near detector. Necessary R\\&D work is proceeding along two main pathways; the first, aimed at the demonstration of modular detector design and the second, at the exploration of new signal readout methods. This two-pronged approach has provided a hig...

VizieR Online Data Catalog: Quasi-periodic pulsations in solar flares (Inglis+, 2016)

Science.gov (United States)

Inglis, A. R.; Ireland, J.; Dennis, B. R.; Hayes, L.; Gallagher, P.

2018-04-01

We have used data from the Geostationary Operational Environmental Satellite (GOES) instrument series, and from Fermi/Gamma-ray Burst Monitor (GBM). For this reason, we choose the interval 2011 February 1 - 2015 December 31, as it not only coincides with the availability of GOES-15 satellite data, but also includes regular solar observations by GBM. GOES satellites are equipped with solar X-ray detectors that record the incident flux in the 0.5-4Å and 1-8Å wavelength ranges. Solar X-ray data from the most recent satellite, GOES-15, has been available since 2010 at a nominal 2s cadence. To access the GOES catalog, we use the Heliophysics Event Knowledgebase (HEK). Fermi/GBM operates in the 8keV-40MeV range and regularly observes emission from solar flares, with a solar duty cycle of ~60%, similar to the solar-dedicated Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI). To accumulate the database of Fermi/GBM events, we use the GBM trigger catalog produced by the instrument team, selecting all events marked as flares. (2 data files).

Results from the crystal ball detector at SPEAR

International Nuclear Information System (INIS)

Bloom, E.D.

1979-11-01

The Crystal Ball detector is a device particularly suited to the measurement of photons with energies lower than 1 GeV. The detector has as its principal component a 16 radiation length thick, highly segmented shell of NaI(Tl) surrounding cylindrical, proportional, and magnetostrictive spark chambers. The main Ball and various elements of the central chambers cover 94% of 4π sr. Segmented endcap NaI(Tl) detectors of 20 radiation lengths behind magneto strictive spark chambers supplement the main Ball. The Ball and endcaps close the solid angle for charged particle and photon detection to 98% of 4π sr. In addition, detectors of interspersed iron and proportional tubes provide for μ-π separation over 15% of 4π sr, about theta/sub CM/ = 90 0 . In this report preliminary results are presented from the data obtained. In particular, QED at E/sub CM/ = 6.5 GeV, R/sub hadron/ and related inclusive distributions, eta branching fractions at J/psi and psi'', and a detailed study of the psionium system are discussed

Performance-Optimization Studies for the CLIC Vertex Detector

CERN Document Server

AUTHOR|(CDS)2085406; Roloff, Philipp

The Compact Linear Collider (CLIC) is a mutli-TeV linear e+e- collider currently under development at CERN. In the post-LHC era, CLIC will allow to explore a great number of searches for New Physics such as the precise measurements of the Higgs boson. In this master thesis, we mainly focus on the development and the improvement of the vertex detector. The vertex detector requires excellent spatial resolution, low mass, geometrical coverage down to low polar angles, high rate readout for the sensors and new cooling technologies for heat removal. Considering such requirements, the CLIC vertex detector technology is far more advanced in comparison to the technologies currently used in particle physics. This project consists of two main parts. In the first part, we study the vertex detector and optimize its geometry for the use of airflow cooling techniques and also for flavor tagging. In the second part, we implement a decoder which can respect the timing constraints for the CLICpix chip, a silicon pixel detect...

MUON DETECTORS: RPC

CERN Multimedia

P. Paolucci

2011-01-01

RPC detector calibration, HV scan Thanks to the high LHC luminosity and to the corresponding high number of muons created in the first part of the 2011 the RPC community had, for the first time, the possibility to calibrate every single detector element (roll).The RPC steering committee provided the guidelines for both data-taking and data analysis and a dedicated task force worked from March to April on this specific issue. The main goal of the RPC calibration was to study the detector efficiency as a function of high-voltage working points, fit the obtained “plateau curve” with a sigmoid function and determine the “best” high-voltage working point of every single roll. On 18th and 19th March, we had eight runs at different voltages. On 27th March, the full analysis was completed, showing that 60% of the rolls had already a very good fit with an average efficiency greater than 93% in the plateau region. To improve the fit we decided to take three more runs (15th April...

Using track detectors in neutron dosimetry

International Nuclear Information System (INIS)

Spurny, F.; Turek, K.

1977-01-01

The usage of track detectors of charged particles provides a new possibility of neutron dosimetry. Presented is a comparison of the main dosimetric characteristics of three various types of track detectots of fast neutrons, i.e. glass in the contact with 232 Th; KODAK LR115 cellulose nitrate; MAKROFOL E polycarbonate. Results of studing energy dependences of detectors are presented. Results obtained using phantoms under radiation fields of various sources of complex gamma-neutron radiation are discussed [ru

Low level photoneutron detection equipment

International Nuclear Information System (INIS)

Ji Changsong; Zhang Yuqin; Li Yuansui

1991-01-01

A low level photoneutron detection equipment has been developed. The photoneutrons produced by interaction of 226 Ra gamma quanta and deutron (D) target are detected with n-n discrimination detector made up of 3 He proportional counter array. The D-content information in the target can be obtained from the measured photoneutron counts. The equipment developed is mainly used for nondestructive D-content measurement of D-devices

New detectors technology for radiology imaging

International Nuclear Information System (INIS)

Cuzin, M.; Peyret, O.

1998-01-01

We summarize the main parameters which describes the radiological image at first and the advantages of pixel detectors. All detectors converts X-rays in charges either with an intermediate step with light or directly in a semi-conductor media. That is true for tomography which is the first domain where digital processing have been taken in account and for radiology where flat panel are now proposed to radiologists. Nevertheless, luminescent stimulated screens are a good way to prepare users with digital radiography. As such technique is not valuable for dynamic acquisition, we describe systems which used standard luminescent screens with CCD cameras or with IIR. Some description and comparison of flat panel independent pixel detectors are given. (authors)

Nanosecond-level time synchronization of autonomous radio detector stations for extensive air showers

NARCIS (Netherlands)

Aab, A.; Abreu, P.; Aglietta, M.; Ahn, E. J.; Al Samarai, I.; Albuquerque, I. F. M.; Allekotte, I.; Messina, S.; Scholten, O.; van den Berg, A.M.

To exploit the full potential of radio measurements of cosmic-ray air showers at MHz frequencies, a detector timing synchronization within 1 ns is needed. Large distributed radio detector arrays such as the Auger Engineering Radio Array (AERA) rely on timing via the Global Positioning System (GPS)

Detector simulation needs for detector designers

International Nuclear Information System (INIS)

Hanson, G.G.

1987-11-01

Computer simulation of the components of SSC detectors and of the complete detectors will be very important for the designs of the detectors. The ratio of events from interesting physics to events from background processes is very low, so detailed understanding of detector response to the backgrounds is needed. Any large detector for the SSC will be very complex and expensive and every effort must be made to design detectors which will have excellent performance and will not have to undergo major rebuilding. Some areas in which computer simulation is particularly needed are pattern recognition in tracking detectors and development of shower simulation code which can be trusted as an aid in the design and optimization of calorimeters, including their electron identification performance. Existing codes require too much computer time to be practical and need to be compared with test beam data at energies of several hundred GeV. Computer simulation of the processing of the data, including electronics response to the signals from the detector components, processing of the data by microprocessors on the detector, the trigger, and data acquisition will be required. In this report we discuss the detector simulation needs for detector designers

Development and characterisation of MCT detectors for space astrophysics at CEA

Science.gov (United States)

Boulade, O.; Baier, N.; Castelein, P.; Cervera, C.; Chorier, P.; Destefanis, G.; Fièque, B.; Gravrand, O.; Guellec, F.; Moreau, V.; Mulet, P.; Pinsard, F.; Zanatta, J.-P.

2017-11-01

The Laboratoire Electronique et Traitement de l'Information (LETI) of the Commissariat à l'Energie Atomique (CEA, Grenoble, France) has been involved in the development of infrared detectors based on HgCdTe (MCT) material for over 30 years, mainly for defence and security programs [1]. Once the building blocks are developed at LETI (MCT material process, diode technology, hybridization, …), the industrialization is performed at SOFRADIR (also in Grenoble, France) which also has its own R&D program [2]. In past years, LETI also developed infrared detectors for space astrophysics in the mid infrared range - the long wave detector of the ISOCAM camera onboard ISO - as well as in the far infrared range - the bolometer arrays of the Herschel/PACS photometer unit -, both instruments which were under the responsibility of the Astrophysics department of CEA (IRFU/SAp, Saclay, France). Nowadays, the infrared detectors used in space and ground based astronomical instruments all come from vendors in the US. For programmatic reasons - increase the number of available vendors, decrease the cost, mitigate possible export regulations, …- as well as political ones - spend european money in Europe -, the European Space Agency (ESA) defined two roadmaps (one in the NIR-SWIR range, one in the MWIR-LWIR range) that will eventually allow for the procurement of infrared detectors for space astrophysics within Europe. The French Space Agency (CNES) also started the same sort of roadmaps, as part of its contribution to the different space missions which involve delivery of instruments by French laboratories. It is important to note that some of the developments foreseen in these roadmaps also apply to Earth Observations. One of the main goal of the ESA and CNES roadmaps is to reduce the level of dark current in MCT devices at all wavelengths. The objective is to use the detectors at the highest temperature where the noise induced by the dark current stays compatible with the photon

On Special Optical Modes and Thermal Issues in Advanced Gravitational Wave Interferometric Detectors

Directory of Open Access Journals (Sweden)

Vinet Jean-Yves

2009-07-01

Full Text Available The sensitivity of present ground-based gravitational wave antennas is too low to detect many events per year. It has, therefore, been planned for years to build advanced detectors allowing actual astrophysical observations and investigations. In such advanced detectors, one major issue is to increase the laser power in order to reduce shot noise. However, this is useless if the thermal noise remains at the current level in the 100 Hz spectral region, where mirrors are the main contributors. Moreover, increasing the laser power gives rise to various spurious thermal effects in the same mirrors. The main goal of the present study is to discuss these issues versus the transverse structure of the readout beam, in order to allow comparison. A number of theoretical studies and experiments have been carried out, regarding thermal noise and thermal effects. We do not discuss experimental problems, but rather focus on some theoretical results in this context about arbitrary order Laguerre–Gauss beams, and other “exotic” beams.

Mechanical design of the CDF SVX II silicon vertex detector

International Nuclear Information System (INIS)

Skarha, J.E.

1994-08-01

A next generation silicon vertex detector is planned at CDF for the 1998 Tevatron collider run with the Main Injector. The SVX II silicon vertex detector will allow high luminosity data-taking, enable online triggering of secondary vertex production, and greatly increase the acceptance for heavy flavor physics at CDF. The design specifications, geometric layout, and early mechanical prototyping work for this detector are discussed

Digital Low Level RF Systems for Fermilab Main Ring and Tevatron

Science.gov (United States)

Chase, B.; Barnes, B.; Meisner, K.

1997-05-01

At Fermilab, a new Low Level RF system is successfully installed and operating in the Main Ring. Installation is proceeding for a Tevatron system. This upgrade replaces aging CAMAC/NIM components for an increase in accuracy, reliability, and flexibility. These VXI systems are based on a custom three channel direct digital synthesizer(DDS) module. Each synthesizer channel is capable of independent or ganged operation for both frequency and phase modulation. New frequency and phase values are computed at a 100kHz rate on the module's Analog Devices ADSP21062 (SHARC) digital signal processor. The DSP concurrently handles feedforward, feedback, and beam manipulations. Higher level state machines and the control system interface are handled at the crate level using the VxWorks operating system. This paper discusses the hardware, software and operational aspects of these LLRF systems.

Determining dose rate with a semiconductor detector - Monte Carlo calculations of the detector response

Energy Technology Data Exchange (ETDEWEB)

Nordenfors, C

1999-02-01

To determine dose rate in a gamma radiation field, based on measurements with a semiconductor detector, it is necessary to know how the detector effects the field. This work aims to describe this effect with Monte Carlo simulations and calculations, that is to identify the detector response function. This is done for a germanium gamma detector. The detector is normally used in the in-situ measurements that is carried out regularly at the department. After the response function is determined it is used to reconstruct a spectrum from an in-situ measurement, a so called unfolding. This is done to be able to calculate fluence rate and dose rate directly from a measured (and unfolded) spectrum. The Monte Carlo code used in this work is EGS4 developed mainly at Stanford Linear Accelerator Center. It is a widely used code package to simulate particle transport. The results of this work indicates that the method could be used as-is since the accuracy of this method compares to other methods already in use to measure dose rate. Bearing in mind that this method provides the nuclide specific dose it is useful, in radiation protection, since knowing what the relations between different nuclides are and how they change is very important when estimating the risks

Degradation of silicon AC-coupled microstrip detectors induced by radiation

Science.gov (United States)

Bacchetta, N.; Bisello, D.; Canali, C.; Fuochi, P. G.; Gotra, Y.; Paccagnella, A.; Verzellesi, G.

1993-12-01

Results are presented showing the radiation response of AC-coupled FOXFET biased microstrip detectors and related test patterns to be used in the microvertex detector of the CDF experiment at Fermi National Laboratory. Radiation tolerance of detectors to gamma and proton irradiation has been tested, and the radiation-induced variations of the DC electrical parameters have been analyzed. The long-term postirradiation behavior of detector characteristics has been studied, and the relevant room-temperature annealing phenomena have been examined. The main radiation damage effects after gamma or proton irradiation of FOXFET biased microstrip detectors consist of an increase in the total leakage current, while both the detector dynamic resistance and FOXFET switching voltage decrease.

Superconducting nano-strip particle detectors

International Nuclear Information System (INIS)

Cristiano, R; Ejrnaes, M; Casaburi, A; Zen, N; Ohkubo, M

2015-01-01

We review progress in the development and applications of superconducting nano-strip particle detectors. Particle detectors based on superconducting nano-strips stem from the parent devices developed for single photon detection (SSPD) and share with them ultra-fast response times (sub-nanosecond) and the ability to operate at a relatively high temperature (2–5 K) compared with other cryogenic detectors. SSPDs have been used in the detection of electrons, neutral and charged ions, and biological macromolecules; nevertheless, the development of superconducting nano-strip particle detectors has mainly been driven by their use in time-of-flight mass spectrometers (TOF-MSs) where the goal of 100% efficiency at large mass values can be achieved. Special emphasis will be given to this case, reporting on the great progress which has been achieved and which permits us to overcome the limitations of existing mass spectrometers represented by low detection efficiency at large masses and charge/mass ambiguity. Furthermore, such progress could represent a breakthrough in the field. In this review article we will introduce the device concept and detection principle, stressing the peculiarities of the nano-strip particle detector as well as its similarities with photon detectors. The development of parallel strip configuration is introduced and extensively discussed, since it has contributed to the significant progress of TOF-MS applications. (paper)

T2K off-axis near detector νμ flux measurement and absolute momentum scale calibration of the off-axis near detector tracker

International Nuclear Information System (INIS)

Blaszczyk, F.

2011-09-01

In this thesis we present the results from the ν μ energy spectrum measurement at T2K's near detector and T2K's near detector tracker absolute momentum scale calibration. First we review the main historical steps and the current state of the art of neutrino physics as well as the theoretical framework required to understand the thesis physics analyses presented later on. In particular we focus on the neutrino oscillation parametrization and the neutrino-matter interaction models. We then describe T2K, an off-axis long baseline neutrino oscillation experiment in Japan which consists of a muon neutrino beam sent from J-PARC to Super- Kamiokande, with a magnetized near detector located at 280 m from the neutrino production site. T2K's main goals are measuring the last unknown angle of the PMNS matrix θ 13 through the search of ν e appearance in the ν μ beam and measuring precisely the atmospheric parameters through muon neutrino disappearance. We briefly describe the detectors, in particular the near detector tracker and its performance. We then present the analyses tools, such as the reconstruction techniques used and how the neutrino charged current interaction events needed for the energy spectrum measurement are selected. The main goal of the thesis, the muon neutrino energy spectrum measurement done with the first T2K data is explained next. We give the motivations for such measurement, the results obtained with the first T2K data sample, and the different systematic errors studied. Finally, the absolute momentum scale calibration of T2K's near detector tractor, done through the reconstruction of the neutral kaon invariant mass, is explained. (author)

Liquid ionizing radiaion detector

International Nuclear Information System (INIS)

deGaston, A.N.

1979-01-01

A normally nonconducting liquid such as liquid hydrocarbon is encased between a pair of electrodes in an enclosure so that when the liquid is subjected to ionizing radiation, the ion pairs so created measurably increase the conductivity of the fluid. The reduced impedance between the electrodes is detectable with a sensitive ohm-meter and indicates the amount of ionizing radiation. The enclosure, the electrodes and the fluid can be constructed of materials that make the response of the detector suitable for calibrating a large range of radiation energy levels. The detector is especially useful in medical applications where tissue equivalent X ray detectors are desired

Epitaxial silicon semiconductor detectors, past developments, future prospects

International Nuclear Information System (INIS)

Gruhn, C.R.

1976-01-01

A review of the main physical characteristics of epitaxial silicon as it relates to detector development is presented. As examples of applications results are presented on (1) epitaxial silicon avalanche diodes (ESAD); signal-to-noise, non-linear aspects of the avalanche gain mechanism, gain-bandwidth product, (2) ultrathin epitaxial silicon surface barrier (ESSB) detectors, response to heavy ions, (3) an all-epitaxial silicon diode (ESD), response to heavy ions, charge transport and charge defect. Future prospects of epitaxial silicon as it relates to new detector designs are summarized

AIM cryocooler developments for HOT detectors

Science.gov (United States)

Rühlich, I.; Mai, M.; Withopf, A.; Rosenhagen, C.

2014-06-01

Significantly increased FPA temperatures for both Mid Wave and Long Wave IR detectors, i.e. HOT detectors, which have been developed in recent years are now leaving the development phase and are entering real application. HOT detectors allowing to push size weight and power (SWaP) of Integrated Detectors Cooler Assemblies (IDCA's) to a new level. Key component mainly driving achievable weight, volume and power consumption is the cryocooler. AIM cryocooler developments are focused on compact, lightweight linear cryocoolers driven by compact and high efficient digital cooler drive electronics (DCE) to also achieve highest MTTF targets. This technology is using moving magnet driving mechanisms and dual or single piston compressors. Whereas SX030 which was presented at SPIE in 2012 consuming less 3 WDC to operate a typical IDCA at 140K, next smaller cooler SX020 is designed to provide sufficient cooling power at detector temperature above 160K. The cooler weight of less than 200g and a total compressor length of 60mm makes it an ideal solution for all applications with limited weight and power budget, like in handheld applications. For operating a typical 640x512, 15μm MW IR detector the power consumption will be less than 1.5WDC. MTTF for the cooler will be in excess of 30,000h and thus achieving low maintenance cost also in 24/7 applications. The SX020 compressor is based on a single piston design with integrated passive balancer in a new design achieves very low exported vibration in the order of 100mN in the compressor axis. AIM is using a modular approach, allowing the chose between 5 different compressor types for one common Stirling expander. The 6mm expander with a total length of 74mm is now available in a new design that fits into standard dewar bores originally designed for rotary coolers. Also available is a 9mm coldfinger in both versions. In development is an ultra-short expander with around 35mm total length to achieve highest compactness. Technical

Experience from operating germanium detectors in GERDA

Science.gov (United States)

Palioselitis, Dimitrios; GERDA Collaboration

2015-05-01

Phase I of the Germanium Detector Array (GERDA) experiment, searching for the neutrinoless double beta (0νββ) decay of 76Ge, was completed in September 2013. The most competitive half-life lower limit for the 0νββ decay of 76Ge was set (T-0ν1/2 > 2.1 · 1025 yr at 90% C.L.). GERDA operates bare Ge diodes immersed in liquid argon. During Phase I, mainly refurbished semi-coaxial high purity Ge detectors from previous experiments were used. The experience gained with handling and operating bare Ge diodes in liquid argon, as well as the stability and performance of the detectors during GERDA Phase I are presented. Thirty additional new enriched BEGe-type detectors were produced and will be used in Phase II. A subgroup of these detectors has already been used successfully in GERDA Phase I. The present paper gives an overview of the production chain of the new germanium detectors, the steps taken to minimise the exposure to cosmic radiation during manufacturing, and the first results of characterisation measurements in vacuum cryostats.

The ATLAS Detector Safety System

CERN Multimedia

Helfried Burckhart; Kathy Pommes; Heidi Sandaker

The ATLAS Detector Safety System (DSS) has the mandate to put the detector in a safe state in case an abnormal situation arises which could be potentially dangerous for the detector. It covers the CERN alarm severity levels 1 and 2, which address serious risks for the equipment. The highest level 3, which also includes danger for persons, is the responsibility of the CERN-wide system CSAM, which always triggers an intervention by the CERN fire brigade. DSS works independently from and hence complements the Detector Control System, which is the tool to operate the experiment. The DSS is organized in a Front- End (FE), which fulfills autonomously the safety functions and a Back-End (BE) for interaction and configuration. The overall layout is shown in the picture below. ATLAS DSS configuration The FE implementation is based on a redundant Programmable Logical Crate (PLC) system which is used also in industry for such safety applications. Each of the two PLCs alone, one located underground and one at the s...

Musculoskeletal imaging with a prototype photon-counting detector.

Science.gov (United States)

Gruber, M; Homolka, P; Chmeissani, M; Uffmann, M; Pretterklieber, M; Kainberger, F

2012-01-01

To test a digital imaging X-ray device based on the direct capture of X-ray photons with pixel detectors, which are coupled with photon-counting readout electronics. The chip consists of a matrix of 256 × 256 pixels with a pixel pitch of 55 μm. A monolithic image of 11.2 cm × 7 cm was obtained by the consecutive displacement approach. Images of embalmed anatomical specimens of eight human hands were obtained at four different dose levels (skin dose 2.4, 6, 12, 25 μGy) with the new detector, as well as with a flat-panel detector. The overall rating scores for the evaluated anatomical regions ranged from 5.23 at the lowest dose level, 6.32 at approximately 6 μGy, 6.70 at 12 μGy, to 6.99 at the highest dose level with the photon-counting system. The corresponding rating scores for the flat-panel detector were 3.84, 5.39, 6.64, and 7.34. When images obtained at the same dose were compared, the new system outperformed the conventional DR system at the two lowest dose levels. At the higher dose levels, there were no significant differences between the two systems. The photon-counting detector has great potential to obtain musculoskeletal images of excellent quality at very low dose levels.

Gbm.auto: A software tool to simplify spatial modelling and Marine Protected Area planning

Science.gov (United States)

Officer, Rick; Clarke, Maurice; Reid, David G.; Brophy, Deirdre

2017-01-01

Boosted Regression Trees. Excellent for data-poor spatial management but hard to use Marine resource managers and scientists often advocate spatial approaches to manage data-poor species. Existing spatial prediction and management techniques are either insufficiently robust, struggle with sparse input data, or make suboptimal use of multiple explanatory variables. Boosted Regression Trees feature excellent performance and are well suited to modelling the distribution of data-limited species, but are extremely complicated and time-consuming to learn and use, hindering access for a wide potential user base and therefore limiting uptake and usage. BRTs automated and simplified for accessible general use with rich feature set We have built a software suite in R which integrates pre-existing functions with new tailor-made functions to automate the processing and predictive mapping of species abundance data: by automating and greatly simplifying Boosted Regression Tree spatial modelling, the gbm.auto R package suite makes this powerful statistical modelling technique more accessible to potential users in the ecological and modelling communities. The package and its documentation allow the user to generate maps of predicted abundance, visualise the representativeness of those abundance maps and to plot the relative influence of explanatory variables and their relationship to the response variables. Databases of the processed model objects and a report explaining all the steps taken within the model are also generated. The package includes a previously unavailable Decision Support Tool which combines estimated escapement biomass (the percentage of an exploited population which must be retained each year to conserve it) with the predicted abundance maps to generate maps showing the location and size of habitat that should be protected to conserve the target stocks (candidate MPAs), based on stakeholder priorities, such as the minimisation of fishing effort displacement. Gbm

Electromechanically cooled germanium radiation detector system

International Nuclear Information System (INIS)

Lavietes, Anthony D.; Joseph Mauger, G.; Anderson, Eric H.

1999-01-01

We have successfully developed and fielded an electromechanically cooled germanium radiation detector (EMC-HPGe) at Lawrence Livermore National Laboratory (LLNL). This detector system was designed to provide optimum energy resolution, long lifetime, and extremely reliable operation for unattended and portable applications. For most analytical applications, high purity germanium (HPGe) detectors are the standard detectors of choice, providing an unsurpassed combination of high energy resolution performance and exceptional detection efficiency. Logistical difficulties associated with providing the required liquid nitrogen (LN) for cooling is the primary reason that these systems are found mainly in laboratories. The EMC-HPGe detector system described in this paper successfully provides HPGe detector performance in a portable instrument that allows for isotopic analysis in the field. It incorporates a unique active vibration control system that allows the use of a Sunpower Stirling cycle cryocooler unit without significant spectral degradation from microphonics. All standard isotopic analysis codes, including MGA and MGA++, GAMANL, GRPANL and MGAU, typically used with HPGe detectors can be used with this system with excellent results. Several national and international Safeguards organisations including the International Atomic Energy Agency (IAEA) and U.S. Department of Energy (DOE) have expressed interest in this system. The detector was combined with custom software and demonstrated as a rapid Field Radiometric Identification System (FRIS) for the U.S. Customs Service . The European Communities' Safeguards Directorate (EURATOM) is field-testing the first Safeguards prototype in their applications. The EMC-HPGe detector system design, recent applications, and results will be highlighted

The Multi-Purpose Detector (MPD) of the collider experiment

Energy Technology Data Exchange (ETDEWEB)

Golovatyuk, V.; Kekelidze, V.; Kolesnikov, V.; Rogachevsky, O. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Sorin, A. [Joint Institute for Nuclear Research, Dubna (Russian Federation); National Research Nuclear University (MEPhI), Moscow (Russian Federation)

2016-08-15

The project NICA (Nuclotron-based Ion Collider fAcility) is aimed to study dense baryonic matter in heavy-ion collisions in the energy range up to √(s{sub NN}) = 11 GeV with average luminosity of L = 10{sup 27} cm{sup -2}s{sup -1} (for {sup 197}Au{sup 79}). The experimental program at the NICA collider will be performed with the Multi-Purpose Detector (MPD). We report on the main physics objectives of the NICA heavy-ion program and present the main detector components. (orig.)

Design of FPGA-based radiation tolerant quench detectors for LHC

Science.gov (United States)

Steckert, J.; Skoczen, A.

2017-04-01

The Large Hadron Collider (LHC) comprises many superconducting circuits. Most elements of these circuits require active protection. The functionality of the quench detectors was initially implemented as microcontroller based equipment. After the initial stage of the LHC operation with beams the introduction of a new type of quench detector began. This article presents briefly the main ideas and architectures applied to the design and the validation of FPGA-based quench detectors.

Design of FPGA-based radiation tolerant quench detectors for LHC

International Nuclear Information System (INIS)

Steckert, J.; Skoczen, A.

2017-01-01

The Large Hadron Collider (LHC) comprises many superconducting circuits. Most elements of these circuits require active protection. The functionality of the quench detectors was initially implemented as microcontroller based equipment. After the initial stage of the LHC operation with beams the introduction of a new type of quench detector began. This article presents briefly the main ideas and architectures applied to the design and the validation of FPGA-based quench detectors.

A VME-based readout system for the CMS Preshower sub-detector

CERN Document Server

Antchev, G; Bialas, W; Da Silva, J C; Kokkas, P; Manthos, N; Reynaud, S; Sidiropoulos, G; Snoeys, W; Vichoudis, P

2007-01-01

The CMS preshower is a fine grain detector that comprises 4288 silicon sensors, each containing 32 strips. The raw data are transferred from the detector to the counting room via 1208 optical fibres. Each fibre carries a 600-byte data packet per event. The maximum average level-1 trigger rate of 100 kHz results in a total data flow of ~72 GB/s from the preshower. For the readout of the preshower, 56 links to the CMS DAQ have been reserved, each having a bandwidth of 200 MB/s (2 kB/event). The total available downstream bandwidth of GB/s necessitates a reduction in the data volume by a factor of at least 7. A modular VME-based system is currently under development. The main objective of each VME board in this system is to acquire on-detector data from at least 22 optical links, perform on-line data reduction and pass the concentrated data to the CMS DAQ. The principle modules that the system is based on are being developed in collaboration with the TOTEM experiment.

Awakening the BALROG: BAyesian Location Reconstruction Of GRBs

Science.gov (United States)

Burgess, J. Michael; Yu, Hoi-Fung; Greiner, Jochen; Mortlock, Daniel J.

2018-05-01

The accurate spatial location of gamma-ray bursts (GRBs) is crucial for both accurately characterizing their spectra and follow-up observations by other instruments. The Fermi Gamma-ray Burst Monitor (GBM) has the largest field of view for detecting GRBs as it views the entire unocculted sky, but as a non-imaging instrument it relies on the relative count rates observed in each of its 14 detectors to localize transients. Improving its ability to accurately locate GRBs and other transients is vital to the paradigm of multimessenger astronomy, including the electromagnetic follow-up of gravitational wave signals. Here we present the BAyesian Location Reconstruction Of GRBs (BALROG) method for localizing and characterizing GBM transients. Our approach eliminates the systematics of previous approaches by simultaneously fitting for the location and spectrum of a source. It also correctly incorporates the uncertainties in the location of a transient into the spectral parameters and produces reliable positional uncertainties for both well-localized sources and those for which the GBM data cannot effectively constrain the position. While computationally expensive, BALROG can be implemented to enable quick follow-up of all GBM transient signals. Also, we identify possible response problems that require attention and caution when using standard, public GBM detector response matrices. Finally, we examine the effects of including the uncertainty in location on the spectral parameters of GRB 080916C. We find that spectral parameters change and no extra components are required when these effects are included in contrast to when we use a fixed location. This finding has the potential to alter both the GRB spectral catalogues and the reported spectral composition of some well-known GRBs.

Ionization smoke detectors - the high-voltage issues

International Nuclear Information System (INIS)

Anon.

1992-01-01

Production of high-voltage ionization smoke detectors ceased in 1978 following the development of lower voltage models which used much smaller amounts of radioactive material. Despite this fact, thousands of high-voltage detectors are still in use today in many large UK companies. The major users argue that there is no reason to stop using their detectors if they are still fit for their purpose - many could last for another 15 to 20 years if properly maintained. But pressure has been mounting on businesses to replace all their high-voltage detectors with new low-voltage models within the next couple of years. This could place a huge financial burden on the companies concerned, with costs possibly running into millions of pounds. Traditionally, the major detector installers offered cleaning and maintenance services for high-voltage detectors to their customers but these have now been withdrawn. The installers give no clear reasons for this decision except that the detectors are outmoded and should be disposed of as soon as possible. Most users would agree that conversion to low-voltage types is inevitable but their main worry is the financial strain of replacing all their detectors - and associated equipment - in one go. They would prefer to phase out their high-voltage detectors in stages over a number of years to spread the costs of conversion. The problems of maintenance is discussed. A dual voltage fire alarm panel which allows the high-voltage detectors to be phased out is mentioned. (Author)

Measurement uncertainties of long-term 222Rn averages at environmental levels using alpha track detectors

International Nuclear Information System (INIS)

Nelson, R.A.

1987-01-01

More than 250 replicate measurements of outdoor Rn concentration integrated over quarterly periods were made to estimate the random component of the measurement uncertainty of Track Etch detectors (type F) under outdoor conditions. The measurements were performed around three U mill tailings piles to provide a range of environmental concentrations. The measurement uncertainty was typically greater than could be accounted for by Poisson counting statistics. Average coefficients of variation of the order of 20% for all measured concentrations were found. It is concluded that alpha track detectors can be successfully used to determine annual average outdoor Rn concentrations through the use of careful quality control procedures. These include rapid deployment and collection of detectors to minimize unintended Rn exposure, careful packaging and shipping to and from the manufacturer, use of direct sunlight shields for all detectors and careful and secure mounting of all detectors in as similar a manner as possible. The use of multiple (at least duplicate) detectors at each monitoring location and an exposure period of no less than one quarter are suggested

Nuclearites search with the TLS detector

International Nuclear Information System (INIS)

Liang, S.; Wada, T.; Nakatsuka, T.; Okei, K.; Saavedra, O.; Takahashi, N.; Tsuji, S.; Yamamoto, I.; Yamashita, Y.; Lan, S.; Okita, M.; Takahashi, N.; Morita, T.; Ishii, R.; Goto, Y.; Iyono, A.; Matsumoto, H.; Nakagawa, M.; Noda, C.; Masuda, M.

2008-01-01

It is shown that a thermoluminescent sheet stack (TLS) detector, consisting of TL sheets and medical x-ray films, is an effective nuclearite detector. The TLS can be used for searching lighter nuclearites at sea level owing to the fact that the usual relativistic particles cannot make their tracks in the TLS unless they have a charge of larger than 50. We will report recent results of searching for lighter nuclearites at sea level

Operational issues of present ATLAS strip detector

CERN Document Server

Yacoob, S; The ATLAS collaboration

2013-01-01

Current results from the successful operation of the Semi-Conductor Tracker (SCT) Detector at the LHC and its status after three years of operation is presented. This note reports on the operation of the detector including an overview of the issues we encountered and the observation of significant increases in leakage currents from bulk damage due to non-ionising radiation, there have been a small number of significant changes effecting detector operation since the contribution to the previous conference in the series [1]. The main emphasis is given to the tracking performance of the SCT and the data quality during the many months of data-taking (the LHC delivered 47 pb

Charge collection in Si detectors irradiated in situ at superfluid helium temperature

Science.gov (United States)

Verbitskaya, Elena; Eremin, Vladimir; Zabrodskii, Andrei; Dehning, Bernd; Kurfürst, Christoph; Sapinski, Mariusz; Bartosik, Marcin R.; Egorov, Nicolai; Härkönen, Jaakko

2015-10-01

Silicon and diamond detectors operated in a superfluid helium bath are currently being considered for the upgrade of the LHC beam loss monitoring system. The detectors would be installed in immediate proximity of the superconducting coils of the triplet magnets. We present here the results of the in situ irradiation test for silicon detectors using 23 GeV protons while keeping the detectors at a temperature of 1.9 K. Red laser (630 nm) Transient Current Technique and DC current measurements were used to study the pulse response and collected charge for silicon detectors irradiated to a maximum radiation fluence of 1×1016 p/cm2. The dependence between collected charge and irradiation fluence was parameterized using the Hecht equation and assumption of a uniform electric field distribution. The collected charge was found to degrade with particle fluence for both bias polarities. We observed that the main factor responsible for this degradation was related to trapping of holes on the donor-type radiation-induced defects. In contrast to expectations, along with formation of donors, acceptor-type defects (electron traps) are introduced into the silicon bulk. This suggests that the current models describing charge collection in irradiated silicon detectors require an extension for taking into account trapping at low temperatures with a contribution of shallow levels. New in situ irradiation tests are needed and planned now to extend statistics of the results and gain a deeper insight into the physics of low temperature detector operation in harsh radiation environment.

Hight resolution Si(Li) X ray detector

International Nuclear Information System (INIS)

Yuan Xianglin; Huang Naizhang; Lin Maocai; Li Zhiyong

1985-01-01

This paper describes the fabrication technology of GL1221 type Si(Li) X ray detector core and the pulse light feedback colded preamplifier fitted on the detector. The energy resolution of the detector system is 165 eV (At 5.89 KeV Mn-K α X ray); the counting rate is 1020 cps, and the electronics noise is 104 eV. The performace of the detector keeps up with the business level of a foreign product of the same kind

Measurement of the total cross section with ALFA Detector at ATLAS

CERN Document Server

Trzebinski, M; The ATLAS collaboration

2017-01-01

The main goals of the Absolute Luminosity For ATLAS (ALFA) detector is to provide an absolute luminosity and total cross section measurement. The measurement method used, the detector alignment and the quality of the collected data are discussed.

Localization of gravitational wave sources with networks of advanced detectors

International Nuclear Information System (INIS)

Klimenko, S.; Mitselmakher, G.; Pankow, C.; Vedovato, G.; Drago, M.; Prodi, G.; Mazzolo, G.; Salemi, F.; Re, V.; Yakushin, I.

2011-01-01

Coincident observations with gravitational wave (GW) detectors and other astronomical instruments are among the main objectives of the experiments with the network of LIGO, Virgo, and GEO detectors. They will become a necessary part of the future GW astronomy as the next generation of advanced detectors comes online. The success of such joint observations directly depends on the source localization capabilities of the GW detectors. In this paper we present studies of the sky localization of transient GW sources with the future advanced detector networks and describe their fundamental properties. By reconstructing sky coordinates of ad hoc signals injected into simulated detector noise, we study the accuracy of the source localization and its dependence on the strength of injected signals, waveforms, and network configurations.

Indoor radon concentration levels in Amman, Zarka and Sault

International Nuclear Information System (INIS)

Khatibeh, A.J.A.H.; Ahmad, N.; Matiullah, A.

1997-01-01

Indoor radon concentration levels in three main cities of Jordan have been measured using CR-39 polymeric nuclear track detectors. CR-39 detectors were placed in polyethylene bags and cups. These bag and cup dosimeters were installed in randomly selected houses. The average value of indoor radon concentration level in the city of Amman was found to be 41.3 Bq m -3 with cup dosimeters and 42.6 Bq m -3 with bag dosimeters. For the district of Zarka, the average value of indoor radon concentration level measured with bag dosimeters was 33.9 Bq m -3 , whereas with cup dosimeters the level was 30.7 Bq m -3 . For Sault and its suburbs, the average value of indoor radon concentration level was found to be 51.2 Bq m -3 with bag dosimeters and 49.8 Bq m -3 with cup dosimeters. (author)

Upgrade of ATLAS ITk Pixel Detector

CERN Document Server

Huegging, Fabian; The ATLAS collaboration

2017-01-01

The high luminosity upgrade of the LHC (HL-LHC) in 2026 will provide new challenges to the ATLAS tracker. The current inner detector will be replaced with an entirely-silicon inner tracker (ITk) which will consist of a five barrel layer Pixel detector surrounded by a four barrel layer Strip detector. The expected high radiation levels are requiring the development of upgraded silicon sensors as well as new a front-end chip. The dense tracking environment will require finer granularity detectors and low mass global and local support structures. The data rates will require new technologies for high bandwidth data transmission and handling. The current status of the ITk ATLAS Pixel detector developments as well as different layout options will be reviewed.

A gas proportional scintillation counter for use in large area detector systems without photomultipliers

International Nuclear Information System (INIS)

Baruch, J.E.F.; Brooke, G.; Kellerman, E.W.; Bateman, J.E.; Connolly, J.F.

1979-01-01

The properties of a prototype gas proportional scintillation (GPS) detector module are described. The module (25X25X14cm 3 ) is intended to form the basic unit of large area (up to approximately 100 m 2 ) calorimetric cosmic ray burst detector. Ionisation from particle tracks in the module is collected onto a point electrode where the GPS signal is generated. A concave mirror focusses this point source onto the end of a fibre optic light guide. In the proposed large area detector these fibres are brought together onto a low light level TV camera which performs the readout. The prototype module has demonstrated an adequate light output for the detection of single muons by such a readout system and also permitted the investigation of the main operating parameters (gas mixture, EHT, pressure, etc) and operational requirements such as proportionality and long term stability. (Auth.)

Luminosity Measurements with the ATLAS Detector

CERN Document Server

Maettig, Stefan; Pauly, T

For almost all measurements performed at the Large Hadron Collider (LHC) one crucial ingredient is the precise knowledge about the integrated luminosity. The determination and precision on the integrated luminosity has direct implications on any cross-section measurement, and its instantaneous measurement gives important feedback on the conditions at the experimental insertions and on the accelerator performance. ATLAS is one of the main experiments at the LHC. In order to provide an accurate and reliable luminosity determination, ATLAS uses a variety of different sub-detectors and algorithms that measure the luminosity simultaneously. One of these sub-detectors are the Beam Condition Monitors (BCM) that were designed to protect the ATLAS detector from potentially dangerous beam losses. Due to its fast readout and very clean signals this diamond detector is providing in addition since May 2011 the official ATLAS luminosity. This thesis describes the calibration and performance of the BCM as a luminosity detec...

On unfolding counting-rate spectra of recoil-proton neutron detectors

International Nuclear Information System (INIS)

Yeivin, Yehuda

1983-01-01

This note proposes a possible scheme for unfolding recoil-proton neutron detector data, in which at first the undistorted proton source spectrum is derived. The main argument in favour of this scheme is that, compared with the conventional scheme, it necessitates somewhat weaker assumptions with respect to the unknown spectrum above the detector's upper energy cutoff, and would therefore be more reliable. We also demonstrate a simple, elementary proof of the wall effect correction for spherical detectors, and, in order to gain insight of the potential merits of the proposed unfolding scheme, illustrate our main argument by considering a hypothetic linear range-energy relation, in which case complete unfolding becomes possible with no assumptions at all on the proton spectrum above the cutoff energy. (author)

Iron-free detector magnet options for the future circular collider

CERN Document Server

AUTHOR|(CDS)2092466; Dudarev, Alexey; Pais Da Silva, Helder Filipe; Rolando, Gabriella; Cure, Benoit; Gaddi, Andrea; Klyukhin, Slava; Gerwig, Hubert; Wagner, Udo; Ten Kate, Herman

2016-01-01

In this paper, several iron-free solenoid-based designs of a detector magnet for the future circular collider for hadron-hadron collisions (FCC-hh) are presented. The detector magnet designs for FCC-hh aim to provide bending power for particles over a wide pseudorapidity range (0 ≤ jηj ≤ 4). To achieve this goal, the main solenoidal detector magnet is combined with a forward magnet system, such as the previously presented force-and-torque-neutral dipole. Here, a solenoid-based alternative, the so-called balanced forward solenoid, is presented which comprises a larger inner solenoid for providing bending power to particles at jηj ≥ 2.5, in combination with a smaller balancing coil for ensuring that the net force and torque on each individual coil is minimized. The balanced forward solenoid is compared to the force-and-torqueneutral dipole and advantages and disadvantages are discussed. In addition, several conceptual solenoidbased detector magnet designs are shown, and quantitatively compared. The main...

Production of ALICE microstrip detectors at ITC-irst