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Sample records for ccl2 accelerates microglia-mediated

  1. CCL2 accelerates microglia-mediated Abeta oligomer formation and progression of neurocognitive dysfunction.

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    Tomomi Kiyota

    2009-07-01

    Full Text Available The linkages between neuroinflammation and Alzheimer's disease (AD pathogenesis are well established. What is not, however, is how specific immune pathways and proteins affect the disease. To this end, we previously demonstrated that transgenic over-expression of CCL2 enhanced microgliosis and induced diffuse amyloid plaque deposition in Tg2576 mice. This rodent model of AD expresses a Swedish beta-amyloid (Abeta precursor protein mutant.We now report that CCL2 transgene expression accelerates deficits in spatial and working memory and hippocampal synaptic transmission in beta-amyloid precursor protein (APP mice as early as 2-3 months of age. This is followed by increased numbers of microglia that are seen surrounding Abeta oligomers. CCL2 does not suppress Abeta degradation. Rather, CCL2 and tumor necrosis factor-alpha directly facilitated Abeta uptake, intracellular Abeta oligomerization, and protein secretion.We posit that CCL2 facilitates Abeta oligomer formation in microglia and propose that such events accelerate memory dysfunction by affecting Abeta seeding in the brain.

  2. Microglia-Mediated Inflammation and Neurodegenerative Disease.

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    Xu, Ling; He, Dan; Bai, Ying

    2016-12-01

    Microglia are the main effectors in the inflammatory process of the central nervous system. As the first line of defense, microglia play an important role in the inflammatory reaction. When there is pathogen invasion or cell debris, microglia will be activated rapidly and remove it, while releasing the inflammatory cytokines to mediate inflammatory reaction. Activated microglia were found surrounding lesions of various neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, muscular amyotrophic lateral sclerosis, and multiple sclerosis. Microglia, the effectors of neuronal degeneration and necrosis, are involved in the removal of necrotic neurons. But over activated microglia may accelerate the process of some neurodegenerative diseases. Activated microglia can release cytotoxic factor and cytokines. Some of them may cause further damage to neuron, and some of them can regulate inflammatory cells to gather to the lesion. Microglia-mediated inflammation was considered to be the possible mechanism for the occurrence or deterioration of neurodegenerative diseases. Therefore, inhibiting the activity of microglia appropriately may be an effective way for the treatment of neurodegenerative diseases.

  3. Chemokines CXCL10 and CCL2

    DEFF Research Database (Denmark)

    Sørensen, Torben Lykke; Sellebjerg, F; Jensen, C V

    2001-01-01

    leukocyte count, the CSF concentration of neopterin, matrix metalloproteinase (MMP)-9, and intrathecal IgG and IgM synthesis. The concentration of CCL2 increased between baseline for 3 weeks in both groups, more distinctly so in patients treated with methylprednisolone. CCL2 correlated negatively with MMP-9...... patients in relapse, whilst levels of CCL2 (MCP-1) were reduced. Here, we report a serial analysis of CSF CXCL10 and CCL2 concentrations in 22 patients with attacks of MS or acute optic neuritis (ON) treated with methylprednisolone, and 26 patients treated with placebo in two randomized controlled trials....... Chemokine concentrations were measured by enzyme linked immunosorbent assay (ELISA) in CSF obtained at baseline and after 3 weeks, and were compared with other measures of intrathecal inflammation. At baseline CSF concentrations of CCL2 were significantly lower in the patient group than in controls...

  4. Contribution of microglia-mediated neuroinflammation to retinal degenerative diseases.

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    Madeira, Maria H; Boia, Raquel; Santos, Paulo F; Ambrósio, António F; Santiago, Ana R

    2015-01-01

    Retinal degenerative diseases are major causes of vision loss and blindness worldwide and are characterized by chronic and progressive neuronal loss. One common feature of retinal degenerative diseases and brain neurodegenerative diseases is chronic neuroinflammation. There is growing evidence that retinal microglia, as in the brain, become activated in the course of retinal degenerative diseases, having a pivotal role in the initiation and propagation of the neurodegenerative process. A better understanding of the events elicited and mediated by retinal microglia will contribute to the clarification of disease etiology and might open new avenues for potential therapeutic interventions. This review aims at giving an overview of the roles of microglia-mediated neuroinflammation in major retinal degenerative diseases like glaucoma, age-related macular degeneration, and diabetic retinopathy.

  5. BUPRENORPHINE DECREASES THE CCL2-MEDIATED CHEMOTACTIC RESPONSE OF MONOCYTES

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    Carvallo, Loreto; Lopez, Lillie; Che, Fa-Yun; Lim, Jihyeon; Eugenin, Eliseo; Williams, Dionna W.; Nieves, Edward; Calderon, Tina M.; Madrid-Aliste, Carlos; Fiser, Andras; Weiss, Louis; Angeletti, Ruth Hogue; Berman, Joan W.

    2015-01-01

    Despite successful cART, approximately 60% of HIV infected people exhibit HIV associated neurocognitive disorders (HAND). CCL2 is elevated in the CNS of infected people with HAND and mediates monocyte influx into the CNS, which is critical in neuroAIDS. Many HIV infected opiate abusers have increased neuroinflammation that may augment HAND. Buprenorphine is used to treat opiate addiction. However, there are few studies that examine its impact on HIV neuropathogenesis. We show that buprenorphine reduces the chemotactic phenotype of monocytes. Buprenorphine decreases the formation of membrane projections in response to CCL2. It also decreases CCL2-induced chemotaxis and mediates a delay in reinsertion of the CCL2 receptor, CCR2, into the cell membrane after CCL2-mediated receptor internalization, suggesting a mechanism of action of buprenorphine. Signaling pathways in CCL2-induced migration include increased phosphorylation of p38 MAPK and of the junctional protein JAM-A. We show that buprenorphine decreases these phosphorylations in CCL2-treated monocytes. Using DAMGO, CTAP, and Nor-BNI, we demonstrate that the effect of buprenorphine on CCL2 signaling is opioid receptor mediated. To identify additional potential mechanisms by which buprenorphine inhibits CCL2-induced monocyte migration, we performed proteomic analyses to characterize additional proteins in monocytes whose phosphorylation after CCL2 treatment was inhibited by buprenorphine. Leukosialin and S100A9, were identified and had not been shown previously be involved in monocyte migration. We propose that buprenorphine limits CCL2-mediated monocyte transmigration into the CNS, thereby reducing neuroinflammation characteristic of HAND. Our findings underscore the use of buprenorphine as a therapeutic for neuroinflammation as well as for addiction. PMID:25716997

  6. Nanomedicine and its application in treatment of microglia-mediated neuroinflammation.

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    Baby, N; Patnala, R; Ling, Eng-Ang; Dheen, S T

    2014-01-01

    Nanomedicine, an emerging therapeutic tool in current medical frontiers, offers targeted drug delivery for many neurodegenerative disorders. Neuroinflammation, a hallmark of many neurodegenerative disorders, is mediated by microglia, the resident immunocompetent cells of the central nervous system (CNS). Microglial cells respond to various stimuli in the CNS resulting in their activation which may have a beneficial or a detrimental effect. In general, the activated microglia remove damaged neurons and infectious agents by phagocytosis, therefore being neuroprotective. However, their chronic activation exacerbates neuronal damage through excessive release of proinflammatory cytokines, chemokines and other inflammatory mediators which contribute to neuroinflammation and subsequent neurodegeneration in the CNS. Hence, controlling microglial inflammatory response and their proliferation has been considered as an important aspect in treating neurodegenerative disorders. Regulatory factors that control microglial activation and proliferation also play an important role in microglia-mediated neuroinflammation and neurotoxicity. Various anti-inflammatory drugs and herbal compounds have been identified in treating microglia-mediated neuroinflammation in the CNS. However, hurdles in crossing blood brain barrier (BBB), expression of metabolic enzymes, presence of efflux pumps and several other factors prevent the entry of these drugs into the CNS. Use of non-degradable delivery systems and microglial activation in response to the drug delivery system further complicate drug delivery to the CNS. Nanomedicine, a nanoparticle-mediated drug delivery system, exhibits immense potential to overcome these hurdles in drug delivery to the CNS enabling new alternatives with significant promises in revolutionising the field of neurodegenerative disease therapy. This review attempts to summarise various regulatory factors in microglia, existing therapeutic strategies in controlling

  7. Spinal injection of docosahexaenoic acid attenuates carrageenan-induced inflammatory pain through inhibition of microglia-mediated neuroinflammation in the spinal cord.

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    Lu, Y; Zhao, L-X; Cao, D-L; Gao, Y-J

    2013-06-25

    Neuroinflammation in the spinal cord plays a critical role in the processing of inflammatory pain. Docosahexaenoic acid (DHA), a predominant omega-3 polyunsaturated fatty acid in the central nervous system, is known to modulate inflammatory responses in various neurodegenerative disorders. In this study, we investigated whether DHA could reduce inflammatory pain and inhibit neuroinflammation in the spinal cord following carrageenan injection in mice. Intrathecal (i.t.) injection of DHA at 15min before carrageenan injection blocked carrageenan-induced pain hypersensitivity for more than 6h. In addition, i.t. injection of DHA at 3h after carrageenan transiently reversed carrageenan-induced heat hyperalgesia and mechanical allodynia. Furthermore, DHA treatment reduced carrageenan-induced activation of microglia, phosphorylation of p38 mitogen-activated protein kinase (MAPK), and production of proinflammatory cytokines (tumor necrosisfactor-α - TNF-α and interleukin-1β - IL-1β) in the L4-5 spinal cord. In cultured microglial cells, DHA dose-dependently reduced lipopolysaccharide (LPS)-induced phosphorylation of p38, production of proinflammatory cytokines (TNF-α, IL-1β, IL-6) and chemokines (CCL2, CCL3 and CXCL10). p38 inhibitor SB203580 inhibited LPS-induced expression of proinflammatory cytokines and chemokines in a dose-dependent manner. Taken together, these results provide evidence that DHA has antinociceptive effect in inflammatory pain, which may be attributed to, at least partially, suppressing a microglia-mediated inflammatory response through inhibition of p38 MAPK activation. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

  8. A small molecule binding HMGB1 and HMGB2 inhibits microglia-mediated neuroinflammation.

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    Lee, Sanghee; Nam, Youngpyo; Koo, Ja Young; Lim, Donghyun; Park, Jongmin; Ock, Jiyeon; Kim, Jaehong; Suk, Kyoungho; Park, Seung Bum

    2014-12-01

    Because of the critical role of neuroinflammation in various neurological diseases, there are continuous efforts to identify new therapeutic targets as well as new therapeutic agents to treat neuroinflammatory diseases. Here we report the discovery of inflachromene (ICM), a microglial inhibitor with anti-inflammatory effects. Using the convergent strategy of phenotypic screening with early stage target identification, we show that the direct binding target of ICM is the high mobility group box (HMGB) proteins. Mode-of-action studies demonstrate that ICM blocks the sequential processes of cytoplasmic localization and extracellular release of HMGBs by perturbing its post-translational modification. In addition, ICM effectively downregulates proinflammatory functions of HMGB and reduces neuronal damage in vivo. Our study reveals that ICM suppresses microglia-mediated inflammation and exerts a neuroprotective effect, demonstrating the therapeutic potential of ICM in neuroinflammatory diseases.

  9. Icariin Reduces Dopaminergic Neuronal Loss and Microglia-Mediated Inflammation in Vivo and in Vitro

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    Guo-Qing Wang

    2018-01-01

    Full Text Available Parkinson’s disease (PD is one of the most common neurodegenerative diseases characterized with a gradual loss of midbrain substantia nigra (SN dopamine (DA neurons. An excessive evidence demonstrated that microglia-mediated inflammation might be involved in the pathogenesis of PD. Thus, inhibition of neuroinflammation might possess a promising potential for PD treatment. Icariin (ICA, a single active component extracted from the Herba Epimedii, presents amounts of pharmacological properties, such as anti-inflammation, anti-oxidant, and anti-aging. Recent studies show ICA produced neuroprotection against brain dysfunction. However, the mechanisms underlying ICA-exerted neuroprotection are fully illuminated. In the present study, two different neurotoxins of 6-hydroxydopamine (6-OHDA and lipopolysaccharide (LPS-induced rat midbrain DA neuronal damage were applied to investigate the neuroprotective effects of ICA. In addition, primary rat midbrain neuron-glia co-cultures were performed to explore the mechanisms underlying ICA-mediated DA neuroprotection. In vitro data showed that ICA protected DA neurons from LPS/6-OHDA-induced DA neuronal damage and inhibited microglia activation and pro-inflammatory factors production via the suppression of nuclear factor-κB (NF-κB pathway activation. In animal results, ICA significantly reduced microglia activation and significantly attenuated LPS/6-OHDA-induced DA neuronal loss and subsequent animal behavior changes. Together, ICA could protect DA neurons against LPS- and 6-OHDA-induced neurotoxicity both in vivo and in vitro. These actions might be closely associated with the inhibition of microglia-mediated neuroinflammation.

  10. TRPV1 receptor inhibition decreases CCL2-induced hyperalgesia

    Czech Academy of Sciences Publication Activity Database

    Špicarová, Diana; Adámek, Pavel; Kalynovska, Nataliia; Mrózková, Petra; Paleček, Jiří

    2014-01-01

    Roč. 81, JUN (2014), s. 75-84 ISSN 0028-3908 R&D Projects: GA ČR(CZ) GA305/09/1228; GA ČR(CZ) GPP303/12/P510; GA ČR(CZ) GBP304/12/G069; GA MŠk(CZ) LH12058 Grant - others:Univerzita Karlova(CZ) 253154 Institutional support: RVO:67985823 Keywords : pain * spinal cord * synaptic transmission * CCL2 * TRPV1 * EPSC Subject RIV: FH - Neurology Impact factor: 5.106, year: 2014

  11. The aqueous extract from Toona sinensis leaves inhibits microglia-mediated neuroinflammation.

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    Wang, Chao-Chuan; Tsai, Yee-Jean; Hsieh, Ya-Ching; Lin, Rong-Jyh; Lin, Chih-Lung

    2014-02-01

    The leaves of Toona sinensis, a well-known traditional oriental medicine, have been prescribed for the treatment of enteritis and infection. Recently, aqueous extracts of Toona sinensis leaves (TSL-1) have demonstrated many biological effects both in vitro and in vivo. In the central nervous system, microglial activation and their proinflammatory responses are considered an important therapeutic strategy for neuroinflammatory disorders such as cerebral ischemia, Alzheimer's disease, and Parkinson's disease. The present study attempted to validate the effect of TSL-1 on microglia-mediated neuroinflammation stimulated by lipopolysaccharide (LPS). As inflammatory parameters, the production of nitric oxide (NO), inducible NO synthase, and tumor necrosis factor-α were evaluated. Our results demonstrate that TSL-1 suppresses LPS-induced NO production, tumor necrosis factor-α secretion, and inducible NO synthase protein expression in a concentration-dependent manner, without causing cytotoxicity. In addition, the inhibitory effects of TSL-1 in LPS-stimulated BV-2 microglia were extended to post-treatment suggesting the therapeutic potential of TSL-1. Therefore, this work provides the future evaluation of the role of TSL-1 in the treatment of neurodegenerative diseases by inhibition of inflammatory mediator production in activated microglia. Copyright © 2013. Published by Elsevier B.V.

  12. Scutellarin as a Potential Therapeutic Agent for Microglia-Mediated Neuroinflammation in Cerebral Ischemia.

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    Yuan, Yun; Fang, Ming; Wu, Chun-Yun; Ling, Eng-Ang

    2016-09-01

    The cerebral ischemia is one of the most common diseases in the central nervous system that causes progressive disability or even death. In this connection, the inflammatory response mediated by the activated microglia is believed to play a central role in this pathogenesis. In the event of brain injury, activated microglia can clear the cellular debris and invading pathogens, release neurotrophic factors, etc., but in chronic activation microglia may cause neuronal death through the release of excessive inflammatory mediators. Therefore, suppression of microglial over-reaction and microglia-mediated neuroinflammation is deemed to be a therapeutic strategy of choice for cerebral ischemic damage. In the search for potential herbal extracts that are endowed with the property in suppressing the microglial activation and amelioration of neuroinflammation, attention has recently been drawn to scutellarin, a Chinese herbal extract. Here, we review the roles of activated microglia and the effects of scutellarin on activated microglia in pathological conditions especially in ischemic stroke. We have further extended the investigation with special reference to the effects of scutellarin on Notch signaling, one of the several signaling pathways known to be involved in microglial activation. Furthermore, in light of our recent experimental evidence that activated microglia can regulate astrogliosis, an interglial "cross-talk" that was amplified by scutellarin, it is suggested that in designing of a more effective therapeutic strategy for clinical management of cerebral ischemia both glial types should be considered collectively.

  13. Beneficial impact of CCL2 and CCL12 neutralization on experimental malignant pleural effusion.

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    Antonia Marazioti

    Full Text Available Using genetic interventions, we previously determined that C-C motif chemokine ligand 2 (CCL2 promotes malignant pleural effusion (MPE formation in mice. Here we conducted preclinical studies aimed at assessing the specific therapeutic potential of antibody-mediated CCL2 blockade against MPE. For this, murine MPEs or skin tumors were generated in C57BL/6 mice by intrapleural or subcutaneous delivery of lung (LLC or colon (MC38 adenocarcinoma cells. Human lung adenocarcinoma cells (A549 were used to induce MPEs in severe combined immunodeficient mice. Intraperitoneal antibodies neutralizing mouse CCL2 and/or CCL12, a murine CCL2 ortholog, were administered at 10 or 50 mg/kg every three days. We found that high doses of CCL2/12 neutralizing antibody treatment (50 mg/kg were required to limit MPE formation by LLC cells. CCL2 and CCL12 blockade were equally potent inhibitors of MPE development by LLC cells. Combined CCL2 and CCL12 neutralization was also effective against MC38-induced MPE and prolonged the survival of mice in both syngeneic models. Mouse-specific CCL2-blockade limited A549-caused xenogeneic MPE, indicating that host-derived CCL2 also contributes to MPE precipitation in mice. The impact of CCL2/12 antagonism was associated with inhibition of immune and vascular MPE-related phenomena, such as inflammation, new blood vessel assembly and plasma extravasation into the pleural space. We conclude that CCL2 and CCL12 blockade are effective against experimental MPE induced by murine and human adenocarcinoma in mice. These results suggest that CCL2-targeted therapies may hold promise for future use against human MPE.

  14. CCL2 recruits T cells into the brain in a CCR2-independent manner

    DEFF Research Database (Denmark)

    Cédile, Oriane; Wlodarczyk, Agnieszka; Owens, Trevor

    2017-01-01

    CCR2, a receptor for CCL2. Expression of another receptor for CCL2, CCR4, and CXCR3, a receptor for CXCL10, which was also induced, were both increased in CCL2-treated CNS. CCR4 was expressed by neurons and astrocytes as well as CD4 T cells, and CXCR3 was expressed by CD4 and CD8 T cells. Chemokine...

  15. Polysaccharides from Ganoderma lucidum attenuate microglia-mediated neuroinflammation and modulate microglial phagocytosis and behavioural response.

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    Cai, Qing; Li, Yuanyuan; Pei, Gang

    2017-03-24

    Ganoderma lucidum (GL) has been widely used in Asian countries for hundreds of years to promote health and longevity. The pharmacological functions of which had been classified, including the activation of innate immune responses, suppression of tumour and modulation of cell proliferations. Effective fractions of Ganoderma lucidum polysaccharides (GLP) had already been reported to regulate the immune system. Nevertheless, the role of GLP in the microglia-mediated neuroinflammation has not been sufficiently elucidated. Further, GLP effect on microglial behavioural modulations in correlation with the inflammatory responses remains to be unravelled. The aim of this work was to quantitatively analyse the contributions of GLP on microglia. The BV2 microglia and primary mouse microglia were stimulated by lipopolysaccharides (LPS) and amyloid beta 42 (Aβ 42 ) oligomer, respectively. Investigation on the effect of GLP was carried by quantitative determination of the microglial pro- and anti-inflammatory cytokine expressions and behavioural modulations including migration, morphology and phagocytosis. Analysis of microglial morphology and phagocytosis modulations was confirmed in the zebrafish brain. Quantitative results revealed that GLP down-regulates LPS- or Aβ-induced pro-inflammatory cytokines and promotes anti-inflammatory cytokine expressions in BV-2 and primary microglia. In addition, GLP attenuates inflammation-related microglial migration, morphological alterations and phagocytosis probabilities. We also showed that modulations of microglial behavioural responses were associated with MCP-1 and C1q expressions. Overall, our study provides an insight into the GLP regulation of LPS- and Aβ-induced neuroinflammation and serves an implication that the neuroprotective function of GLP might be achieved through modulation of microglial inflammatory and behavioural responses.

  16. Chemokines CXCL10 and CCL2: differential involvement in intrathecal inflammation in multiple sclerosis

    DEFF Research Database (Denmark)

    Sørensen, T.L.; Sellebjerg, F; Jensen, C.V.

    2001-01-01

    leukocyte count, the CSF concentration of neopterin, matrix metalloproteinase (MMP)-9, and intrathecal IgG and IgM synthesis. The concentration of CCL2 increased between baseline for 3 weeks in both groups, more distinctly so in patients treated with methylprednisolone. CCL2 correlated negatively with MMP-9...... patients in relapse, whilst levels of CCL2 (MCP-1) were reduced. Here, we report a serial analysis of CSF CXCL10 and CCL2 concentrations in 22 patients with attacks of MS or acute optic neuritis (ON) treated with methylprednisolone, and 26 patients treated with placebo in two randomized controlled trials....... Chemokine concentrations were measured by enzyme linked immunosorbent assay (ELISA) in CSF obtained at baseline and after 3 weeks, and were compared with other measures of intrathecal inflammation. At baseline CSF concentrations of CCL2 were significantly lower in the patient group than in controls...

  17. CCL2/MCP-1 modulation of microglial activation and proliferation

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    Garcia-Bueno Borja

    2011-07-01

    Full Text Available Abstract Background Monocyte chemoattractant protein (CCL2/MCP-1 is a chemokine that attracts cells involved in the immune/inflammatory response. As microglia are one of the main cell types sustaining inflammation in brain, we proposed here to analyze the direct effects of MCP-1 on cultured primary microglia. Methods Primary microglia and neuronal cultures were obtained from neonatal and embryonic Wistar rats, respectively. Microglia were incubated with different concentrations of recombinant MCP-1 and LPS. Cell proliferation was quantified by measuring incorporation of bromodeoxyuridine (BrdU. Nitrite accumulation was measured using the Griess assay. The expression and synthesis of different proteins was measured by RT-PCR and ELISA. Cell death was quantified by measuring release of LDH into the culture medium. Results MCP-1 treatment (50 ng/ml, 24 h did not induce morphological changes in microglial cultures. Protein and mRNA levels of different cytokines were measured, showing that MCP-1 was not able to induce proinflammatory cytokines (IL-1β, IL6, MIP-1α, either by itself or in combination with LPS. A similar lack of effect was observed when measuring inducible nitric oxide synthase (NOS2 expression or accumulation of nitrites in the culture media as a different indicator of microglial activation. MCP-1 was also unable to alter the expression of different trophic factors that were reduced by LPS treatment. In order to explore the possible release of other products by microglia and their potential neurotoxicity, neurons were co-cultured with microglia: no death of neurons could be detected when treated with MCP-1. However, the presence of MCP-1 induced proliferation of microglia, an effect opposite to that observed with LPS. Conclusion These data indicate that, while causing migration and proliferation of microglia, MCP-1 does not appear to directly activate an inflammatory response in this cell type, and therefore, other factors may be

  18. Chemokine CCL2 and chemokine receptor CCR2 in early active multiple sclerosis

    DEFF Research Database (Denmark)

    Sørensen, Torben Lykke; Ransohoff, R M; Strieter, R M

    2004-01-01

    The chemokine monocyte chemoattractant protein (MCP)-1/CCL2 and its receptor CCR2 have been strongly implicated in disease pathogenesis in experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis (MS), whereas data on the CCL2-CCR2 axis are scarce in MS. We studied...... the expression of CCR2 on leukocytes in blood and cerebrospinal fluid (CSF) from patients with monosymptomatic optic neuritis and MS, and the concentration of CCL2 in the CSF from these patients. Results were compared with the results in non-inflammatory neurological controls and were correlated with other...... parameters (magnetic resonance imaging and CSF data). Our findings suggest a limited role for CCL2/CCR2 in early active MS....

  19. BACTERIAL CLEARANCE IN SEPTIC MICE IS MODULATED BY MCP-1/CCL2 AND NITRIC OXIDE

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    Gomes, Rachel N.; Teixeira-Cunha, Mariana G. A.; Figueiredo, Rodrigo T.; Almeida, Patricia E.; Alves, Silvio C.; Bozza, Patrícia T.; Bozza, Fernando A.; Bozza, Marcelo T.; Zimmerman, Guy A.; Castro-Faria-Neto, Hugo C.

    2013-01-01

    Bacterial clearance is one of the most important beneficial consequences of the innate immune response. Chemokines are important mediators controlling leukocyte trafficking and activation, whereas reactive oxygen and nitrogen species are effectors in bacterial killing. In the present work, we used in vivo and in vitro models of infections to study the role of monocyte chemoattractant protein 1 (MCP-1)/CCL2 and nitric oxide (NO) in the bacterial clearance in sepsis. Our results show that MCP-1/CCL2 and NO levels are increased in the peritoneal cavity of mice 6 h after sepsis induced by cecal ligation and puncture. Pretreatment with anti–MCP-1/CCL2 monoclonal antibodies increased the number of colony-forming units (CFUs) recovered in the peritoneal lavage fluid. Moreover, CFU counts were increased in the peritoneal fluid of CCR2−/− mice subjected to cecal ligation and puncture. In vitro stimulation of peritoneal macrophages with recombinant MCP-1/CCL2 reduced CFU counts in the supernatant after challenge with Escherichia coli. Conversely, treatment with anti–MCP-1/CCL2 increased CFU counts under the same experimental condition. Stimulation of cultured macrophages with MCP-1/CCL2 and interferon had a synergistic effect on NO production. Macrophages from CCL2−/− mice showed a consistent decrease in NO production when compared with wild-type controls after stimulation with LPS + interferon. Finally, we showed incubation of macrophages with E. coli, and the ERK inhibitor U0126 increased CFU numbers and decreased intracellular levels of NO. In conclusion, we demonstrated for the first time that MCP-1/CCL2 has a crucial role in the clearance of bacteria by mechanisms involving increased expression of inducible NO synthase and production of NO by ERK signaling pathways. PMID:23247123

  20. CCL2-ethanol interactions and hippocampal synaptic protein expression in a transgenic mouse model

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    Donna eGruol

    2014-04-01

    Full Text Available Chronic exposure to ethanol produces a number of detrimental effects on behavior. Neuroadaptive changes in brain structure or function underlie these behavioral changes and may be transient or persistent in nature. Central to the functional changes are alterations in the biology of neuronal and glial cells of the brain. Recent data show that ethanol induces glial cells of the brain to produce elevated levels of neuroimmune factors including CCL2, a key innate immune chemokine. Depending on the conditions of ethanol exposure, the upregulated levels of CCL2 can be transient or persistent and outlast the period of ethanol exposure. Importantly, results indicate that the upregulated levels of CCL2 may lead to CCL2-ethanol interactions that mediate or regulate the effects of ethanol on the brain. Glial cells are in close association with neurons and regulate many neuronal functions. Therefore, effects of ethanol on glial cells may underlie some of the effects of ethanol on neurons. To investigate this possibility, we are studying the effects of chronic ethanol on hippocampal synaptic function in a transgenic mouse model that expresses elevated levels of CCL2 in the brain through enhanced glial expression, a situation know to occur in alcoholics. Both CCL2 and ethanol have been reported to alter synaptic function in the hippocampus. In the current study, we determined if interactions are evident between CCL2 and ethanol at level of hippocampal synaptic proteins. Two ethanol exposure paradigms were used; the first involved ethanol exposure by drinking and the second involved ethanol exposure in a paradigm that combines drinking plus ethanol vapor. The first paradigm does not produce dependence on ethanol, whereas the second paradigm is commonly used to produce ethanol dependence. Results show modest effects of both ethanol exposure paradigms on the level of synaptic proteins in the hippocampus of CCL2 transgenic mice compared with their non

  1. Having a Coffee Break: The Impact of Caffeine Consumption on Microglia-Mediated Inflammation in Neurodegenerative Diseases

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    Maria H. Madeira

    2017-01-01

    Full Text Available Caffeine is the major component of coffee and the most consumed psychostimulant in the world and at nontoxic doses acts as a nonselective adenosine receptor antagonist. Epidemiological evidence suggests that caffeine consumption reduces the risk of several neurological and neurodegenerative diseases. However, despite the beneficial effects of caffeine consumption in human health and behaviour, the mechanisms by which it impacts the pathophysiology of neurodegenerative diseases still remain to be clarified. A promising hypothesis is that caffeine controls microglia-mediated neuroinflammatory response associated with the majority of neurodegenerative conditions. Accordingly, it has been already described that the modulation of adenosine receptors, namely, the A2A receptor, affords neuroprotection through the control of microglia reactivity and neuroinflammation. In this review, we will summarize the main effects of caffeine in the modulation of neuroinflammation in neurodegenerative diseases.

  2. Having a Coffee Break: The Impact of Caffeine Consumption on Microglia-Mediated Inflammation in Neurodegenerative Diseases.

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    Madeira, Maria H; Boia, Raquel; Ambrósio, António F; Santiago, Ana R

    2017-01-01

    Caffeine is the major component of coffee and the most consumed psychostimulant in the world and at nontoxic doses acts as a nonselective adenosine receptor antagonist. Epidemiological evidence suggests that caffeine consumption reduces the risk of several neurological and neurodegenerative diseases. However, despite the beneficial effects of caffeine consumption in human health and behaviour, the mechanisms by which it impacts the pathophysiology of neurodegenerative diseases still remain to be clarified. A promising hypothesis is that caffeine controls microglia-mediated neuroinflammatory response associated with the majority of neurodegenerative conditions. Accordingly, it has been already described that the modulation of adenosine receptors, namely, the A 2A receptor, affords neuroprotection through the control of microglia reactivity and neuroinflammation. In this review, we will summarize the main effects of caffeine in the modulation of neuroinflammation in neurodegenerative diseases.

  3. The cystathionine β-synthase/hydrogen sulfide pathway contributes to microglia-mediated neuroinflammation following cerebral ischemia.

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    Zhang, Minjie; Wu, Xiaowei; Xu, Yingxiu; He, Meijun; Yang, Jiaying; Li, Jie; Li, Yuyao; Ao, Guizhen; Cheng, Jian; Jia, Jia

    2017-11-01

    The mechanisms underlying neuroinflammation following cerebral ischemia remain unclear. Hydrogen sulfide (H 2 S), a newly identified gasotransmitter, has been reported to regulate inflammation. In the current study, we investigated whether the endogenous H 2 S production pathway contributed to microglia-mediated neuroinflammation following stroke. We used a mouse middle cerebral artery occlusion (MCAO) model and an in vitro cellular model to mimic ischemia-induced microglial neuroinflammation. Expression of the H 2 S synthase cystathionine β-synthase (CBS) and H 2 S synthetic activity were rapidly decreased in the ischemic brain tissue following MCAO. Consistently, when cultured microglia were polarized toward a pro-inflammatory phenotype with conditioned medium collected from neurons that had been subjected to oxygen-glucose deprivation (OGD neuron CM), they displayed reduced CBS expression and H 2 S production. Enhancing H 2 S bioavailability either by overexpressing CBS or by supplementing with exogenous H 2 S donors promoted a shift in microglial polarization from ischemia-induced pro-inflammatory phenotypes toward anti-inflammatory phenotypes. Mechanistically, microglia that were exposed to OGD neuron CM displayed reduced activation of AMP-activated protein kinase (AMPK), which was rescued by overexpressing CBS or by supplementing with H 2 S donors. Moreover, the promoting effects of H 2 S donors on microglial anti-inflammatory polarization were abolished by an AMPK inhibitor or CaMKKβ inhibitor. Our results suggested that reduced CBS-H 2 S-AMPK cascade activity contributed to microglia-mediated neuroinflammation following stroke. Targeting the CBS-H 2 S pathway is a promising therapeutic approach for ischemic stroke. Copyright © 2017. Published by Elsevier Inc.

  4. Transgenic mice with increased astrocyte expression of CCL2 show altered behavioral effects of alcohol.

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    Bray, Jennifer G; Roberts, Amanda J; Gruol, Donna L

    2017-06-23

    Emerging research provides strong evidence that activation of CNS glial cells occurs in neurological diseases and brain injury and results in elevated production of neuroimmune factors. These factors can contribute to pathophysiological processes that lead to altered CNS function. Recently, studies have also shown that both acute and chronic alcohol consumption can produce activation of CNS glial cells and the production of neuroimmune factors, particularly the chemokine ligand 2 (CCL2). The consequences of alcohol-induced increases in CCL2 levels in the CNS have yet to be fully elucidated. Our studies focus on the hypothesis that increased levels of CCL2 in the CNS produce neuroadaptive changes that modify the actions of alcohol on the CNS. We utilized behavioral testing in transgenic mice that express elevated levels of CCL2 to test this hypothesis. The increased level of CCL2 in the transgenic mice involves increased astrocyte expression. Transgenic mice and their non-transgenic littermate controls were subjected to one of two alcohol exposure paradigms, a two-bottle choice alcohol drinking procedure that does not produce alcohol dependence or a chronic intermittent alcohol procedure that produces alcohol dependence. Several behavioral tests were carried out including the Barnes maze, Y-maze, cued and contextual conditioned fear test, light-dark transfer, and forced swim test. Comparisons between alcohol naïve, non-dependent, and alcohol-dependent CCL2 transgenic and non-transgenic mice show that elevated levels of CCL2 in the CNS interact with alcohol in tests for alcohol drinking, spatial learning, and associative learning. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  5. CCL2 responses to Mycobacterium tuberculosis are associated with disease severity in tuberculosis.

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    Zahra Hasan

    Full Text Available BACKGROUND: Leucocyte activating chemokines such as CCL2, CCL3, and CXCL8 together with proinflammatory IFNgamma, TNFalpha and downmodulatory IL10 play a central role in the restriction of M. tuberculosis infections, but is unclear whether these markers are indicative of tuberculosis disease severity. METHODOLOGY: We investigated live M. tuberculosis- and M. bovis BCG-induced peripheral blood mononuclear cell responses in patients with tuberculosis (TB and healthy endemic controls (ECs, n = 36. TB patients comprised pulmonary (PTB, n = 34 and extrapulmonary groups, subdivided into those with less severe localized extrapulmonary TB (L-ETB, n = 16 or severe disseminated ETB (D-ETB, n = 16. Secretion of CCL2, IFNgamma, IL10 and CCL3, and mRNA expression of CCL2, TNFalpha, CCL3 and CXCL8 were determined. RESULTS: M. tuberculosis- and BCG-induced CCL2 secretion was significantly increased in both PTB and D-ETB (p<0.05, p<0.01 as compared with L-ETB patients. CCL2 secretion in response to M. tuberculosis was significantly greater than to BCG in the PTB and D-ETB groups. M. tuberculosis-induced CCL2 mRNA transcription was greater in PTB than L-ETB (p = 0.023, while CCL2 was reduced in L-ETB as compared with D-ETB (p = 0.005 patients. M. tuberculosis-induced IFNgamma was greater in L-ETB than PTB (p = 0.04, while BCG-induced IFNgamma was greater in L-ETB as compared with D-ETB patients (p = 0.036. TNFalpha mRNA expression was raised in PTB as compared with L-ETB group in response to M. tuberculosis (p = 0.02 and BCG (p = 0.03. Mycobacterium-induced CCL3 and CXCL8 was comparable between TB groups. CONCLUSIONS: The increased CCL2 and TNFalpha in PTB patients may support effective leucocyte recruitment and M. tuberculosis localization. CCL2 alone is associated with severity of TB, possibly due to increased systemic inflammation found in severe disseminated TB or due to increased monocyte infiltration to lung parenchyma in pulmonary disease.

  6. CCL2 and CCL5 Are Novel Therapeutic Targets for Estrogen-Dependent Breast Cancer.

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    Svensson, Susanne; Abrahamsson, Annelie; Rodriguez, Gabriela Vazquez; Olsson, Anna-Karin; Jensen, Lasse; Cao, Yihai; Dabrosin, Charlotta

    2015-08-15

    Novel therapeutic targets of estrogen receptor (ER)-positive breast cancers are urgently needed because current antiestrogen therapy causes severe adverse effects, nearly 50% of patients are intrinsically resistant, and the majority of recurrences have maintained ER expression. We investigated the role of estrogen-dependent chemokine expression and subsequent cancer growth in human tissues and experimental breast cancer models. For in vivo sampling of human chemokines, microdialysis was used in breast cancers of women or normal human breast tissue before and after tamoxifen therapy. Estrogen exposure and targeted therapies were assessed in immune competent PyMT murine breast cancer, orthotopic human breast cancers in nude mice, cell culture of cancer cells, and freshly isolated human macrophages. Cancer cell dissemination was investigated using zebrafish. ER(+) cancers in women produced high levels of extracellular CCL2 and CCL5 in vivo, which was associated with infiltration of tumor-associated macrophages. In experimental breast cancer, estradiol enhanced macrophage influx and angiogenesis through increased release of CCL2, CCL5, and vascular endothelial growth factor. These effects were inhibited by anti-CCL2 or anti-CCL5 therapy, which resulted in potent inhibition of cancer growth. In addition, estradiol induced a protumorigenic activation of the macrophages. In a zebrafish model, macrophages increased cancer cell dissemination via CCL2 and CCL5 in the presence of estradiol, which was inhibited with anti-CCL2 and anti-CCL5 treatment. Our findings shed new light on the mechanisms underlying the progression of ER(+) breast cancer and indicate the potential of novel therapies targeting CCL2 and CCL5 pathways. ©2015 American Association for Cancer Research.

  7. CCL2 Serum Levels and Adiposity Are Associated with the Polymorphic Phenotypes -2518A on CCL2 and 64ILE on CCR2 in a Mexican Population with Insulin Resistance

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    Milton-Omar Guzmán-Ornelas

    2016-01-01

    Full Text Available Genetic susceptibility has been described in insulin resistance (IR. Chemokine (C-C motif ligand-2 (CCL2 is overexpressed in white adipose tissue and is the ligand of C-C motif receptor-2 (CCR2. The CCL2 G-2518A polymorphism is known to regulate gene expression, whereas the physiological effects of the CCR2Val64Ile polymorphism are unknown. The aim of the study is to investigate the relationship between these polymorphisms with soluble CCL2 levels (sCCL2, metabolic markers, and adiposity. In a cross-sectional study we included 380 Mexican-Mestizo individuals, classified with IR according to Stern criteria. Polymorphism was identified using PCR-RFLP/sequence-specific primers. Anthropometrics and metabolic markers were measured by routine methods and adipokines and sCCL2 by ELISA. The CCL2 polymorphism was associated with IR (polymorphic A+ phenotype frequencies were 70.9%, 82.6%, in individuals with and without IR, resp.. Phenotype carriers CCL2 (A+ displayed lower body mass and fat indexes, insulin and HOMA-IR, and higher adiponectin levels. Individuals with IR presented higher sCCL2 compared to individuals without IR and was associated with CCR2 (Ile+ phenotype. The double-polymorphic phenotype carriers (A+/Ile+ exhibited higher sCCL2 than double-wild-type phenotype carriers (A−/Ile−. The present findings suggest that sCCL2 production possibly will be associated with the adiposity and polymorphic phenotypes of CCL2 and CCR2, in Mexican-Mestizos with IR.

  8. Immune response CC Chemokines, CCL2 and CCL5 are associated with Pulmonary Sarcoidosis

    LENUS (Irish Health Repository)

    Palchevskiy, Vyacheslav

    2011-04-04

    Abstract Background Pulmonary sarcoidosis involves an intense leukocyte infiltration of the lung with the formation of non-necrotizing granulomas. CC chemokines (chemokine (C-C motif) ligand 2 (CCL2)-CCL5) are chemoattractants of mononuclear cells and act through seven transmembrane G-coupled receptors. Previous studies have demonstrated conflicting results with regard to the associations of these chemokines with sarcoidosis. In an effort to clarify previous discrepancies, we performed the largest observational study to date of CC chemokines in bronchoalveolar lavage fluid (BALF) from patients with pulmonary sarcoidosis. Results BALF chemokine levels from 72 patients affected by pulmonary sarcoidosis were analyzed by enzyme-linked immunosorbent assay (ELISA) and compared to 8 healthy volunteers. BALF CCL3 and CCL4 levels from pulmonary sarcoidosis patients were not increased compared to controls. However, CCL2 and CCL5 levels were elevated, and subgroup analysis showed higher levels of both chemokines in all stages of pulmonary sarcoidosis. CCL2, CCL5, CC chemokine receptor type 1 (CCR1), CCR2 and CCR3 were expressed from mononuclear cells forming the lung granulomas, while CCR5 was only found on mast cells. Conclusions These data suggest that CCL2 and CCL5 are important mediators in recruiting CCR1, CCR2, and CCR3 expressing mononuclear cells as well as CCR5-expressing mast cells during all stages of pulmonary sarcoidosis.

  9. Testosterone increases CCL-2 expression in visceral adipose tissue from obese women of reproductive age.

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    Crisosto, Nicolás; Flores, Cristián; Maliqueo, Manuel; Echiburú, Bárbara; Vásquez, Jaime; Maluenda, Fernando; Sir-Petermann, Teresa

    2017-03-15

    Hyperandrogenic states and obesity in women are associated with insulin-resistance. Androgens reduce glucose uptake in adipose cells and increase TNFα production in peripheral monocytes. Inflammatory cytokines have a known detrimental effect on insulin resistance. The aim of the present study was to explore the role of testosterone in local cytokine production in visceral adipose tissue from women of reproductive age. Twenty-four women 18-40 years old, undergoing elective abdominal surgery for benign and non-inflammatory conditions, were recruited for the study. Women with clinical hyperandrogenism, diabetes, hepatic or renal dysfunction, hypothyroidism, BMI> 40 or drugs known to interfere with hormonal levels or fat metabolism were excluded. Women were classified into two groups according to BMI, non-obese (NO; BMI obese (O; BMI 30-40). A basal blood sample was drawn at the time of surgery for the measurement of glucose, insulin, total testosterone, lipid profile and circulating CCL-2, IL-6 and total adiponectin. Omental fat tissue (10 g) was obtained in all women. Samples of 300 mg of minced adipose tissue were incubated with vehicle (CTL) or testosterone (T) 10 -9  M to 10 -6  M for 24, 48 or 72 h. CCL-2, IL-6, TNFα, androgen Receptor (AR) mRNA levels were measured by Real Time quantitative polymerase chain reaction (qPCR) and normalized to GAPDH expression. Secretion of CCL-2 and IL-6 was measured in conditioned media by ELISA. Expression of CCL-2 and IL-6 at 24 h in CTLs was significantly higher in the obese group compared to the non-obese group (2.81 ± 0.43 fold for CCL-2; p = 0.005 and 3.26 ± 0.73 fold for IL-6; p = 0.03). At 48 and 72 h there were no differences between both groups in any of the markers. In the total group without T stimulation (CTL) there were significant correlations between: TNFα expression at 24 h and BMI (r = 0.708; p = 0.005), TGC levels (r = 0.904; p = 0.004), total Cholesterol (r = 0.904; p = 0

  10. Minocycline, a microglial inhibitor, blocks spinal CCL2-induced heat hyperalgesia and augmentation of glutamatergic transmission in substantia gelatinosa neurons.

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    Huang, Chung-Yu; Chen, Ying-Ling; Li, Allen H; Lu, Juu-Chin; Wang, Hung-Li

    2014-01-10

    Several lines of evidence suggest that CCL2 could initiate the hyperalgesia of neuropathic pain by causing central sensitization of spinal dorsal horn neurons and facilitating nociceptive transmission in the spinal dorsal horn. The cellular and molecular mechanisms by which CCL2 enhances spinal pain transmission and causes hyperalgesia remain unknown. The substantia gelatinosa (lamina II) of the spinal dorsal horn plays a critical role in nociceptive transmission. An activated spinal microglia, which is believed to release pro-inflammatory cytokines including TNF-α, plays an important role in the development of neuropathic pain, and CCL2 is a key mediator for spinal microglia activation. In the present study, we tested the hypothesis that spinal CCL2 causes the central sensitization of substantia gelatinosa neurons and enhances spinal nociceptive transmission by activating the spinal microglia and augmenting glutamatergic transmission in lamina II neurons. CCL2 was intrathecally administered to 2-month-old male rats. An intrathecal injection of CCL2 induced heat hyperalgesia, which was assessed using the hot plate test. Whole-cell voltage-clamp recordings substantia gelatinosa neurons in spinal cord slices were performed to record glutamatergic excitatory postsynaptic currents (EPSCs) and GABAergic inhibitory postsynaptic currents (IPSCs). The hot plate test showed that 1 day after the intrathecal injection of CCL2 (1 μg), the latency of hind-paw withdrawal caused by a heat stimulus was significantly reduced in rats. One day after the intrathecal administration of CCL2, the amplitude of the evoked glutamatergic EPSCs and the frequency of spontaneous glutamatergic miniature EPSCs (mEPSCs) were significantly increased in outer lamina II neurons. Intrathecal co-injection of minocycline, a specific inhibitor of microglial activation, and CCL2 blocked the CCL2-induced reduction in the latency of hind-paw withdrawal and thermal hyperalgesia. Following intrathecal co

  11. Slow CCL2-dependent translocation of biopersistent particles from muscle to brain.

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    Khan, Zakir; Combadière, Christophe; Authier, François-Jérôme; Itier, Valérie; Lux, François; Exley, Christopher; Mahrouf-Yorgov, Meriem; Decrouy, Xavier; Moretto, Philippe; Tillement, Olivier; Gherardi, Romain K; Cadusseau, Josette

    2013-04-04

    Long-term biodistribution of nanomaterials used in medicine is largely unknown. This is the case for alum, the most widely used vaccine adjuvant, which is a nanocrystalline compound spontaneously forming micron/submicron-sized agglomerates. Although generally well tolerated, alum is occasionally detected within monocyte-lineage cells long after immunization in presumably susceptible individuals with systemic/neurologic manifestations or autoimmune (inflammatory) syndrome induced by adjuvants (ASIA). On the grounds of preliminary investigations in 252 patients with alum-associated ASIA showing both a selective increase of circulating CCL2, the major monocyte chemoattractant, and a variation in the CCL2 gene, we designed mouse experiments to assess biodistribution of vaccine-derived aluminum and of alum-particle fluorescent surrogates injected in muscle. Aluminum was detected in tissues by Morin stain and particle induced X-ray emission) (PIXE) Both 500 nm fluorescent latex beads and vaccine alum agglomerates-sized nanohybrids (Al-Rho) were used. Intramuscular injection of alum-containing vaccine was associated with the appearance of aluminum deposits in distant organs, such as spleen and brain where they were still detected one year after injection. Both fluorescent materials injected into muscle translocated to draining lymph nodes (DLNs) and thereafter were detected associated with phagocytes in blood and spleen. Particles linearly accumulated in the brain up to the six-month endpoint; they were first found in perivascular CD11b+ cells and then in microglia and other neural cells. DLN ablation dramatically reduced the biodistribution. Cerebral translocation was not observed after direct intravenous injection, but significantly increased in mice with chronically altered blood-brain-barrier. Loss/gain-of-function experiments consistently implicated CCL2 in systemic diffusion of Al-Rho particles captured by monocyte-lineage cells and in their subsequent neurodelivery

  12. Piper sarmentosum Roxb. confers neuroprotection on beta-amyloid (Aβ)-induced microglia-mediated neuroinflammation and attenuates tau hyperphosphorylation in SH-SY5Y cells.

    Science.gov (United States)

    Yeo, Emilia Tze Ying; Wong, Kelly Wang Ling; See, Mun Ling; Wong, Ka Yan; Gan, Sook Yee; Chan, Elaine Wan Ling

    2018-05-10

    Piper sarmentosum Roxb. (PS), belonging to Piperaceae family, is an edible plant with medicinal properties. It is traditionally used by the Malays to treat headache and boost memory. Pharmacological studies revealed that PS exhibits anti-inflammatory, anti-oxidant, anti-acetylcholinesterase, and anti-depressant-like effects. In view of this, the present study aimed to investigate the anti-inflammatory actions of PS and its potential neuroprotective effects against beta-amyloid (Aβ)-induced microglia-mediated neurotoxicity. The inhibitory effects of hexane (L HXN ), dichloromethane (L DCM ), ethyl acetate (L EA ) and methanol (L MEOH ) extracts from leaves of PS on Aβ-induced production and mRNA expression of pro-inflammatory mediators in BV-2 microglial cells were assessed using colorimetric assay with Griess reagent, ELISA kit and real-time RT-PCR respectively. Subsequently, MTT reduction assay was used to evaluate the neuroprotective effects of PS leaf extracts against Aβ-induced microglia-mediated neurotoxicity in SH-SY5Y neuroblastoma cells. The levels of tau proteins phosphorylated at threonine 231 (pT231) and total tau proteins (T-tau) were determined using ELISA kits. Polar extracts of PS leaves (L EA and L MEOH ) reduced the Aβ-induced secretion of pro-inflammatory cytokines (IL-1β and TNF-α) in BV-2 cells by downregulating the mRNA expressions of pro-inflammatory cytokines. The inhibition of nitric oxide (NO) production could be due to the free radical scavenging activity of the extracts. In addition, conditioned media from Aβ-induced BV-2 cells pre-treated with L EA and L MEOH protected SH-SY5Y cells against microglia-mediated neurotoxicity. Further mechanistic study suggested that the neuroprotective effects were associated with the downregulation of phosphorylated tau proteins. The present study suggests that polar extracts of PS leaves confer neuroprotection against Aβ-induced microglia-mediated neurotoxicity in SH-SY5Y cells by attenuating tau

  13. Electroacupunctre improves motor impairment via inhibition of microglia-mediated neuroinflammation in the sensorimotor cortex after ischemic stroke.

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    Liu, Weilin; Wang, Xian; Yang, Shanli; Huang, Jia; Xue, Xiehua; Zheng, Yi; Shang, Guanhao; Tao, Jing; Chen, Lidian

    2016-04-15

    Electroacupuncture (EA) is one of the safety and effective therapies for improving neurological and sensorimotor impairment via blockade of inappropriate inflammatory responses. However, the mechanisms of anti-inflammation involved is far from been fully elucidated. Focal cerebral ischemic stroke was administered by the middle cerebral artery occlusion and reperfusion (MCAO/R) surgery. The MCAO/R rats were accepted EA treatment at the LI 11 and ST 36 acupoints for consecutive 3days. The neurological outcome, animal behaviors test and molecular biology assays were used to evaluate the MCAO/R model and therapeutic effect of EA. EA treatment for MCAO rats showed a significant reduction in the infarct volumes accompanied by functional recovery in mNSS outcomes, motor function performances. The possible mechanisms that EA treatment attenuated the over-activation of Iba-1 and ED1 positive microglia in the peri-infract sensorimotor cortex. Simultaneously, both tissue and serum protein levels of the tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) were decreased by EA treatment in MCAO/R injured rats. The levels of inflammatory cytokine tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6) were decreased in the peri-infract sensorimotor cortex and blood serum of MCAO/R injured rats after EA treatment. Furthermore, we found that EA treatment prevented from the nucleus translocation of NF-κB p65 and suppressed the expression of p38 mitogen-activated protein kinase (p38 MAPK) and myeloid differentiation factor 88 (MyD88) in the peri-infract sensorimotor cortex. The findings from this study indicated that EA improved the motor impairment via inhibition of microglia-mediated neuroinflammation that invoked NF-κB p65, p38 MAPK and MyD88 produced proinflammatory cytokine in the peri-infract sensorimotor cortex of rats following ischemic stroke. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. CCL2 is Upregulated by Decreased miR-122 Expression in Iron-Overload-Induced Hepatic Inflammation

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    Yuxiao Tang

    2017-11-01

    Full Text Available Background/Aims: Iron overload (IO is accompanied by hepatic inflammation. The chemokine (C-C motif ligand 2 (CCL2 mediates inflammation, and its overexpression is associated with IO. However, whether IO results in CCL2 overexpression in the liver and the underlying mechanisms are unclear. Methods: We subjected mice to IO by administering intraperitoneal injections of dextran-iron or by feeding mice a 3% dextran-iron diet to observe the effects of IO on miR-122/CCL2 expression through real-time qPCR and Western blot analysis. We also used indicators, including the expression of the inflammatory cytokine, the inflammation score based on H&E staining and the serum content of ALT and AST to evaluate the effects of IO on hepatic inflammation. Meanwhile, we observed the effects of vitamin E on IO-induced hepatic inflammation. In cells, we used 100 µΜ FeSO4 or 30 µΜ Holo-Tf to produce IO and observed the roles of miR-122 in regulating CCL2 expression by using miR-122 mimics or inhibitors to overexpress or inhibit miR-122. Then, we used a dual-luciferase reporter assay to prove that miR-122 regulates CCL2 expression through direct binding to its complementary sequence in the CCL2 mRNA 3’UTR. Results: IO induces the downregulation of miR-122 and the upregulation of CCL2, as well as inflammatory responses both in vitro and in vivo. Although IO-induced oxidative stress is eliminated by the antioxidant vitamin E, IO-induced hepatic inflammation still exists, which probably can be explained by the fact that vitamin E has no effects on the miR-122/CCL2 pathway. In in vitro experiments, the overexpression and inhibition of miR-122 significantly reduced and increased CCL2 expression, respectively. The dual-luciferase reporter assay indicates that miR-122 binds CCL2 mRNA 3’UTR. Conclusion: We propose the roles of miR-122/CCL2 in IO-induced hepatic inflammation. Our studies should provide a new clue for developing clinical strategies for patients with IO.

  15. Diode laser spectra of CCl2F2 near 10.8 muon M: Air-broadening effects

    Science.gov (United States)

    Jennings, D. E.

    1977-01-01

    Laboratory spectra of CCL2F2 in the 10.8 micron region was recorded, using a tuneable diode laser spectrometer. Effects of air-broadening at pressures up to 48 Torr show that spectral structure should be exhibited under high resolution at altitudes as low as 19 Km. The single line, pressure-broadening coefficient for CCL2F2 was estimated to be 8 MHz/Torr FWHM.

  16. Astrocyte-derived CCL2 participates in surgery-induced cognitive dysfunction and neuroinflammation via evoking microglia activation.

    Science.gov (United States)

    Xu, Jiawen; Dong, Hongquan; Qian, Qingqing; Zhang, Xiang; Wang, Yiwei; Jin, Wenjie; Qian, Yanning

    2017-08-14

    Neuroinflammation induced by peripheral trauma plays a key role in the development of postoperative cognitive dysfunction (POCD). Substantial evidence points to reactive glia as a pivotal factor during the inflammation process. However, little is known about the functional interactions between astrocytes and microglia. Recent evidence suggests the involvement of the CCL2-CCR2 pathway in CNS inflammation-related diseases. Our previous studies have suggested that astrocyte-derived CCL2 can induce microglial activation in vitro. Within this context, we sought to determine if the CCL2/CCR2 axis is involved in the crosstalk between astrocytes and microglia, contributing to increased neuroinflammation. Here, we show that tibial fracture surgery promoted CCL2 upregulation in activated astrocytes, increased CCR2 expression in activated microglia, and induced deficits in learning and memory. Site-directed pre-injection of RS504393, a CCR2 antagonist, inhibited this effect by reducing microglial activation, M1 polarization, inflammatory cytokines, and neuronal injury and death and improving cognitive function. Taken together, these data implicate CCL2-CCR2 signaling in astrocyte-mediated microglial activation in central nervous system (CNS) inflammation and suggest that interference with CCL2 signaling could constitute another potential therapeutic target for POCD. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Inflammatory Monocytes Promote Perineural Invasion via CCL2-Mediated Recruitment and Cathepsin B Expression.

    Science.gov (United States)

    Bakst, Richard L; Xiong, Huizhong; Chen, Chun-Hao; Deborde, Sylvie; Lyubchik, Anna; Zhou, Yi; He, Shizhi; McNamara, William; Lee, Sei-Young; Olson, Oakley C; Leiner, Ingrid M; Marcadis, Andrea R; Keith, James W; Al-Ahmadie, Hikmat A; Katabi, Nora; Gil, Ziv; Vakiani, Efsevia; Joyce, Johanna A; Pamer, Eric; Wong, Richard J

    2017-11-15

    Perineural invasion (PNI) is an ominous event strongly linked to poor clinical outcome. Cells residing within peripheral nerves collaborate with cancer cells to enable PNI, but the contributing conditions within the tumor microenvironment are not well understood. Here, we show that CCR2-expressing inflammatory monocytes (IM) are preferentially recruited to sites of PNI, where they differentiate into macrophages and potentiate nerve invasion through a cathepsin B-mediated process. A series of adoptive transfer experiments with genetically engineered donors and recipients demonstrated that IM recruitment to nerves was driven by CCL2 released from Schwann cells at the site of PNI, but not CCL7, an alternate ligand for CCR2. Interruption of either CCL2-CCR2 signaling or cathepsin B function significantly impaired PNI in vivo Correlative studies in human specimens demonstrated that cathepsin B-producing macrophages were enriched in invaded nerves, which was associated with increased local tumor recurrence. These findings deepen our understanding of PNI pathogenesis and illuminate how PNI is driven in part by corruption of a nerve repair program. Further, they support the exploration of inhibiting IM recruitment and function as a targeted therapy for PNI. Cancer Res; 77(22); 6400-14. ©2017 AACR . ©2017 American Association for Cancer Research.

  18. Astrocyte-Derived CCL2 is Associated with M1 Activation and Recruitment of Cultured Microglial Cells

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    Mingfeng He

    2016-02-01

    Full Text Available Background/Aims: Microglia are an essential player in central nervous system inflammation. Recent studies have demonstrated that the astrocytic chemokine, CCL2, is associated with microglial activation in vivo. However, CCL2-induced microglial activation has not yet been studied in vitro. The purpose of the current study was to understand the role of astrocyte-derived CCL2 in microglial activation and to elucidate the underlying mechanism(s. Methods: Primary astrocytes were pre-treated with CCL2 siRNA and stimulated with TNF-α. The culture medium (CM was collected and added to cultures of microglia, which were incubated with and without CCR2 inhibitor. Microglial cells were analyzed by quantitative RT-PCR to determine whether they polarized to the M1 or M2 state. Microglial migratory ability was assessed by transwell migration assay. Results: TNF-α stimulated the release of CCL2 from astrocytes, even if the culture media containing TNF-α was replaced with fresh media after 3 h. CM from TNF-α-stimulated astrocytes successfully induced microglial activation, which was ascertained by increased activation of M1 and enhanced migration ability. In contrast, CM from astrocytes pretreated with CCL2 siRNA showed no effect on microglial activation, compared to controls. Additionally, microglia pre-treated with RS102895, a CCR2 inhibitor, were resistant to activation by CM from TNF-α-stimulated astrocytes. Conclusion: This study demonstrates that the CCL2/CCR2 pathway of astrocyte-induced microglial activation is associated with M1 polarization and enhanced migration ability, indicating that this pathway could be a useful target to ameliorate inflammation in the central nervous system.

  19. Levo-Corydalmine Alleviates Neuropathic Cancer Pain Induced by Tumor Compression via the CCL2/CCR2 Pathway

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    Yahui Hu

    2017-06-01

    Full Text Available Background: Tumor compression-induced pain (TCIP is a complex pathological cancer pain. Spinal glial cells play a critical role in maintenance of cancer pain by releasing proinflammatory cytokines and chemokines. In this study, we verified the role of levo-corydalmine (l-CDL on TCIP. Methods: Spontaneous pain, paw withdrawal threshold and latency were assessed using TCIP mouse model. Immunofluorescence was used to identify the reactions of glia. RT-PCR and western blot or ELISA were used to determine mRNA or protein expression of tumor necrosis factor-α (TNF-α, interlukin-1β (IL-1β, CC chemokine ligand 2 (CCL2 and chemotactic cytokine receptor 2 (CCR2 in vivo and in vitro. Results: l-CDL significantly attenuated TCIP hypersensitivity, accompanying with downregulation of TNF-α and IL-1β expression levels and declined astrocytes and microglial activation. It also significantly decreased the expression of the mRNA and protein level for CCL2 and CCR2. Further, l-CDL could suppress TNF-α-induced astrocytes activation and IL-1β expression through downregulating the CCL2/CCR2. Besides, CCL2-induced BV-microglia activation and inflammatory factors secretion were suppressed by l-CDL via CCR2. Conclusions: Suppression of CCL2/CCR2 by l-CDL may contribute to alleviate TCIP, offering an alternative medication for TCIP.

  20. Chitin elicits CCL2 from airway epithelial cells and induces CCR2-dependent innate allergic inflammation in the lung

    Science.gov (United States)

    Roy, René M.; Wüthrich, Marcel; Klein, Bruce S.

    2012-01-01

    Chitin exposure in the lung induces eosinophilia and alternative activation of macrophages, and is correlated with allergic airway disease. However, the mechanism underlying chitin-induced polarization of macrophages is poorly understood. Here, we show that chitin induces alternative activation of macrophages in vivo, but does not do so directly in vitro. We further show that airway epithelial cells bind chitin in vitro and produce CCL2 in response to chitin both in vitro and in vivo. Supernatants of chitin exposed epithelial cells promoted alternative activation of macrophages in vitro, whereas antibody neutralization of CCL2 in the supernate abolished the alternative activation of macrophages. CCL2 acted redundantly in vivo, but mice lacking the CCL2 receptor, CCR2, showed impaired alternative activation of macrophages in response to chitin, as measured by arginase I, CCL17 and CCL22 expression. Furthermore, CCR2KO mice exposed to chitin had diminished ROS products in the lung, blunted eosinophil and monocyte recruitment, and impaired eosinophil functions as measured by expression of CCL5, IL13 and CCL11. Thus, airway epithelial cells secrete CCL2 in response to chitin and CCR2 signaling mediates chitin-induced alternative activation of macrophages and allergic inflammation in vivo. PMID:22851704

  1. Social stress-enhanced severity of Citrobacter rodentium induced colitis is CCL2-dependent and attenuated by probiotic Lactobacillus reuteri

    Science.gov (United States)

    Mackos, Amy R.; Galley, Jeffrey D.; Eubank, Timothy D.; Easterling, Robert S.; Parry, Nicola M.; Fox, James G.; Lyte, Mark; Bailey, Michael T.

    2015-01-01

    Psychological stressors are known to affect colonic diseases but the mechanisms by which this occurs, and whether probiotics can prevent stressor effects, are not understood. Because inflammatory monocytes that traffic into the colon can exacerbate colitis, we tested whether CCL2, a chemokine involved in monocyte recruitment, was necessary for stressor-induced exacerbation of infectious colitis. Mice were exposed to a social disruption stressor that entails repeated social defeat. During stressor exposure, mice were orally challenged with Citrobacter rodentium to induce a colonic inflammatory response. Exposure to the stressor during challenge resulted in significantly higher colonic pathogen levels, translocation to the spleen, increases in colonic macrophages, and increases in inflammatory cytokines and chemokines. The stressor-enhanced severity of C. rodentium-induced colitis was not evident in CCL2−/− mice, indicating the effects of the stressor are CCL2-dependent. Additionally, we tested whether probiotic intervention could attenuate stressor-enhanced infectious colitis by reducing monocyte/macrophage accumulation. Treating mice with probiotic Lactobacillus reuteri reduced CCL2 mRNA levels in the colon, and attenuated stressor-enhanced infectious colitis. These data demonstrate that probiotic L. reuteri can prevent the exacerbating effects of stressor exposure on pathogen-induced colitis, and suggest that one mechanism by which this occurs is through a down-regulation of the chemokine CCL2. PMID:26422754

  2. Genetic polymorphism of CCL2-2510 and susceptibility to enterovirus 71 encephalitis in a Chinese population.

    Science.gov (United States)

    Han, Zhen-liang; Li, Ji-an; Chen, Zong-bo

    2014-09-01

    The study was performed in 36 Chinese patients with enterovirus 71 (EV71) encephalitis and 141 patients with EV71-related hand, foot and mouth disease (HFMD) without encephalitis. Genotyping was done by the polymerase chain reaction-restriction fragment length polymorphism technique. Patients with EV71 encephalitis had a significantly higher frequency of the CCL2-2510GG genotypes when compared to patients with EV71-related HFMD without encephalitis (66.7% vs. 41.8%, p=0.028). The frequency of CCL2-2510G alleles was also significantly higher among the patients with EV71 encephalitis than among patients with EV71-related HFMD without encephalitis (79.2% vs. 64.9%, OR=2.1, 95% CI=1.1-3.8, P=0.023). Significant differences were found in gender, age, fever days, white blood cell count, C-reactive protein level, blood glucose concentration, and CCL2 level among genotypes of CCL2-2510A/G in EV71-infected patients, but no significant differences were found in alanine aminotransferase, aspartate aminotransferase, or creatine kinase myocardial isozyme levels or in cerebrospinal fluid evaluations (except monocytes) in patients with EV71 encephalitis. These findings suggest that the CCL2-2510G allele is associated with susceptibility to EV71 encephalitis in Chinese patients.

  3. Methionine sulfoxide reductase A negatively controls microglia-mediated neuroinflammation via inhibiting ROS/MAPKs/NF-κB signaling pathways through a catalytic antioxidant function.

    Science.gov (United States)

    Fan, Hua; Wu, Peng-Fei; Zhang, Ling; Hu, Zhuang-Li; Wang, Wen; Guan, Xin-Lei; Luo, Han; Ni, Ming; Yang, Jing-Wen; Li, Ming-Xing; Chen, Jian-Guo; Wang, Fang

    2015-04-01

    Oxidative burst is one of the earliest biochemical events in the inflammatory activation of microglia. Here, we investigated the potential role of methionine sulfoxide reductase A (MsrA), a key antioxidant enzyme, in the control of microglia-mediated neuroinflammation. MsrA was detected in rat microglia and its expression was upregulated on microglial activation. Silencing of MsrA exacerbated lipopolysaccharide (LPS)-induced activation of microglia and the production of inflammatory markers, indicating that MsrA may function as an endogenous protective mechanism for limiting uncontrolled neuroinflammation. Application of exogenous MsrA by transducing Tat-rMsrA fusion protein into microglia attenuated LPS-induced neuroinflammatory events, which was indicated by an increased Iba1 (a specific microglial marker) expression and the secretion of pro-inflammatory cytokines, and this attenuation was accompanied by inhibiting multiple signaling pathways such as p38 and ERK mitogen-activated protein kinases (MAPKs) and nuclear factor kappaB (NF-κB). These effects were due to MsrA-mediated reactive oxygen species (ROS) elimination, which may be derived from a catalytic effect of MsrA on the reaction of methionine with ROS. Furthermore, the transduction of Tat-rMsrA fusion protein suppressed the activation of microglia and the expression of pro-inflammatory factors in a rat model of neuroinflammation in vivo. This study provides the first direct evidence for the biological significance of MsrA in microglia-mediated neuroinflammation. Our data provide a profound insight into the role of endogenous antioxidative defense systems such as MsrA in the control of microglial function.

  4. Sevoflurane Exaggerates Cognitive Decline in a Rat Model of Chronic Intermittent Hypoxia by Aggravating Microglia-Mediated Neuroinflammation via Downregulation of PPAR-γ in the Hippocampus.

    Science.gov (United States)

    Dong, Ping; Zhao, Jian; Li, Ning; Lingling, Lu; Li, Liang; Zhang, Xiyan; Bo, Yang; Li, Zhang; Li, Dongliang

    2018-03-21

    Postoperative cognitive dysfunction is a common complication associated with anesthesia and surgery. Sevoflurane is a widely used volatile anesthetic in the clinical setting. Preclinical studies show that sevoflurane alone does not appear to cause cognitive dysfunction. Here, we examined whether sevoflurane induces cognitive decline under chronic intermittent hypoxia (CIH) conditions. Rats were exposed to CIH or control for 4 weeks. Two weeks after starting intermittent hypoxia, these animals underwent either 2.6 % sevoflurane or vehicle exposure for 4 hours. Four weeks after CIH, Morris Water Maze task showed that both groups of CIH rats exhibited significantly longer latency to locate the hidden platform and had shorter dwell-time in the goal quadrant compared with respective controls. Notably, CIH + sevoflurane rats had much higher latency and less dwell-time than CIH + vehicle rats. Molecular studies revealed that pro-inflammatory cytokine expression and activated microglia in the hippocampus were increased in both groups of CIH rats, with greater increases in CIH + sevoflurane rats. No differences in above measured parameters were observed between two control groups. Sevoflurane reduced PPAR-γ expression and activity in both control and CIH rats. Moreover, activated microglia was positively correlated with proinflammatory cytokine expression and negatively correlated with PPAR-γ expression and activity in CIH groups. The results suggest that microglia-mediated neuroinflammation in the hippocampus plays an important role in the pathogenesis of CIH-associated cognitive dysfunction, and that a moderate duration of sevoflurane exaggerates cognitive decline under CIH conditions by aggravating microglia-mediated neuroinflammation via downregulation of PPAR-γ in the hippocampus. Copyright © 2018. Published by Elsevier B.V.

  5. α-Asarone attenuates microglia-mediated neuroinflammation by inhibiting NF kappa B activation and mitigates MPTP-induced behavioral deficits in a mouse model of Parkinson's disease.

    Science.gov (United States)

    Kim, Byung-Wook; Koppula, Sushruta; Kumar, Hemant; Park, Ju-Young; Kim, Il-Woung; More, Sandeep V; Kim, In-Su; Han, Sang-Don; Kim, Si-Kwan; Yoon, Sung-Hwa; Choi, Dong-Kug

    2015-10-01

    The selective loss of dopaminergic neurons in Parkinson's disease (PD) is associated with microglial activation. Therefore, the importance of early therapeutic intervention to inhibit microglial activation would be an effective strategy to alleviate the progression of PD. α-Asarone, an active compound found in Araceae and Annonaceae plant species has been used to improve various disease conditions including central nervous system disorders. In the present study the in vitro and in vivo therapeutic effects of α-asarone isolated from the rhizome of Acorus gramineus Solander was evaluated on microglia-mediated neuroinflammation and neuroprotection. Lipopolysaccharide (LPS)-stimulated BV-2 microglial cells were used to evaluate in vitro effects. 1-methyl-4 phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced mouse model of PD was developed to study the neuroprotective effects of α-asarone in vivo. The results indicated that α-asarone significantly attenuated the LPS-stimulated increase in neuroinflammatory responses and suppressed pro-inflammatory cytokine production in BV-2 cells. Mechanistic study revealed that α-asarone inhibited the LPS-stimulated activation via regulation of nuclear factor kappa-B by blocking degradation of inhibitor kappa B-alpha signaling in BV-2 microglial cells. In in vivo studies, MPTP intoxication to mice resulted in brain microglial activation and significant behavioral deficits. Prophylactic treatment with α-asarone suppressed microglial activation and attenuated PD-like behavioral impairments as assessed by the Y-maze and pole tests. Taken together, these data demonstrate that α-asarone is a promising neuroprotective agent that should be further evaluated and developed for future prevention and treatment of microglia-mediated neuroinflammatory conditions including PD. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. NF-kappaB-driven STAT2 and CCL2 expression in astrocytes in response to brain injury

    DEFF Research Database (Denmark)

    Khorooshi, Reza; Babcock, Alicia A; Owens, Trevor

    2008-01-01

    -regulation and phosphorylation were NF-kappaB -dependent since they did not occur in the lesion-reactive hippocampus of transgenic mice with specific inhibition of NF-kappaB activation in astrocytes. We further showed that lack of NF-kappaB signaling significantly reduced injury-induced CCL2 expression as well as leukocyte...... infiltration. Our results suggest that NF-kappaB signaling in astrocytes controls expression of both STAT2 and CCL2, and thus regulates infiltration of leukocytes into lesion-reactive hippocampus after axonal injury. Taken together, these findings indicate a central role for astrocytes in directing immune...... induces glial response. Astrocytes are the major glial population in the CNS. We examined expression of STATs and the chemokine CCL2 and their relationship to astroglial NF-kappaB signaling in the CNS following axonal transection. Double labeling with Mac-1/CD11b and glial fibrillary acidic protein...

  7. NF-kappaB-driven STAT2 and CCL2 expression in astrocytes in response to brain injury

    DEFF Research Database (Denmark)

    Khorooshi, Reza; Babcock, Alicia A; Owens, Trevor

    2008-01-01

    -regulation and phosphorylation were NF-kappaB -dependent since they did not occur in the lesion-reactive hippocampus of transgenic mice with specific inhibition of NF-kappaB activation in astrocytes. We further showed that lack of NF-kappaB signaling significantly reduced injury-induced CCL2 expression as well as leukocyte...... infiltration. Our results suggest that NF-kappaB signaling in astrocytes controls expression of both STAT2 and CCL2, and thus regulates infiltration of leukocytes into lesion-reactive hippocampus after axonal injury. Taken together, these findings indicate a central role for astrocytes in directing immune...

  8. Chemokine CCL2 and its receptor CCR2 in the dorsal root ganglion contribute to oxaliplatin-induced mechanical hypersensitivity.

    Science.gov (United States)

    Illias, A M; Gist, A C; Zhang, H; Kosturakis, A K; Dougherty, P M

    2018-03-15

    Activation of innate immune mechanisms within the dorsal root ganglion (DRG) and spinal dorsal horn has been shown to play a key role in the development of neuropathic pain including paclitaxel-related chemotherapy-induced peripheral neuropathy (CIPN). Here we tested whether similar mechanisms are generalizable to oxaliplatin-induced CIPN. After a single intraperitoneal injection of 3mg/kg oxaliplatin, mechanical withdrawal threshold and the expression of C-C chemokine ligand 2 (CCL2) and its receptor, CCR2 in the DRG were measured by behavioral testing and immunohistochemical (IHC) staining, respectively. Mechanical responsiveness increased from the first day after oxaliplatin injection and persisted until day 15, the last day of this experiment. IHC showed that the expression of CCL2/CCR2 started to increase by 4hrs after oxaliplatin treatment, was significantly increased at day 4, and then both signals became normalized by day15. Co-treatment with intrathecal anti-CCL2 antibodies prevented the development of oxaliplatin-induced mechanical hyper-responsiveness, and transiently reversed established hyperalgesia when given 1 week after chemotherapy. This is the first study to demonstrate CCL2/CCR2 signaling in a model of oxaliplatin-related CIPN; and it further shows that blocking of this signal can attenuate the development of oxaliplatin-induced mechanical hyperalgesia. Activation of innate immune mechanisms may therefore be a generalized basis for CIPN irrespective of the specific class of agent.

  9. Kinetics of plasma procalcitonin, soluble CD14, CCL2 and IL-10 after a sublethal infusion of lipopolysaccharide in horses.

    Science.gov (United States)

    Bonelli, Francesca; Meucci, Valentina; Divers, Thomas J; Wagner, Bettina; Intorre, Luigi; Sgorbini, Micaela

    2017-02-01

    Endotoxemia represents a significant clinical and economic problem for the equine industry. This study assesses the kinetics of soluble CD14 (sCD14), chemokine (CC motif) ligand 2 (CCL2), interleukin 10 (IL-10) and plasma procalcitonin (PCT) in healthy horses after the intravenous infusion of lipopolysaccharide (LPS). The aim was to contribute to the basic understanding of the equine species-specific kinetics of these molecules in response to LPS exposure, which could support further findings in clinical studies and identify valuable inflammatory biomarkers for equine practice. Eleven healthy horses were involved in this experimental in vivo study. Horses were classified as healthy before the LPS infusion. After the pre-infusion blood collection (T0), all horses received an infusion of E. coli endotoxin (30ng/kg over 30min). Data and samples were collected 1h (T1), 2 (T2), 3 (T3) and 24h (T24) after infusion. Plasma sCD14, CCL2 and IL-10 were evaluated with a fluorescent bead-based assay, while PCT was evaluated with an equine PCT ELISA assay. A one-way ANOVA test was performed between each blood-sampling time for PCT, sCD14 and IL-10, and a Friedman test was performed for CCL2. Plasma PCT, IL-10 and CCL2 concentrations increased statistically significantly at T1, T2 and T3 compared to T0. No statistically significant differences were found between plasma IL-10 and CCL2 concentrations between T0 vs T24, although plasma PCT values remained high 24h after LPS infusion. Plasma sCD14 concentration showed no statistically significant differences for any of sampling times. Our results demonstrate that LPS injection into healthy horses results in PCT, CCL2 and IL-10 increases in plasma without an increase in sCD14. The increases in PCT, CCL2 and IL-10 are related to the inflammatory response induced by circulating lipopolysaccharide. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. The rs1024611 in the CCL2 gene and risk of gynecological cancer in Asians: a meta-analysis.

    Science.gov (United States)

    He, Shuying; Zhang, Xiuzhen

    2018-02-20

    The -2518A/G (rs1024611) polymorphism of the CCL2 (C-C motif chemokine ligand 2), also known as MCP-1 (monocyte chemotactic protein-1) gene, has been reported to be associated with increased gynecological cancer risk, but the results are conflicting. In this analysis, 1089 cases and 1553 controls from six publications were used to investigate the association between CCL2-2518A/G (rs1024611) polymorphism and the risk of gynecological cancer with a meta-analytic approach. Studies published on EBSCO, EMBASE, Web of Science, PubMed, SpringerLink, ScienceDirect, Weipu, and CNKI databases were identified (last update was on November 3, 2015). Six articles focused on the association between CCL2-2518A/G (rs1024611) polymorphism, and gynecological cancer risk was selected and data were extracted. The cancer type included endometrial cancer (n = 1), breast cancer (n = 2), ovarian cancer (n = 2), and cervical cancer (n = 1). All statistical analyses were performed using the STATA version 12.0 software. The meta-analysis showed that CCL2-2518A/G (rs1024611) polymorphism is associated with risk of gynecological cancer (GG vs AG + AA, OR = 1.55, 95%CI = 1.07-2.24, P < 0.05; AA vs GG, OR = 0.59 95%CI = 0.38-0.92, P < 0.05). Notably, the subgroup analysis demonstrated that the genotype AA is associated with a reduced gynecological cancer risk in Asians, but an increased risk when compared to AG in Europeans. Our data demonstrated the CCL2-2518A/G (rs1024611) polymorphism is significantly associated with risk of gynecological cancer, and the association differs by ethnicity.

  11. Amniotic fluid stem cells inhibit the progression of bleomycin-induced pulmonary fibrosis via CCL2 modulation in bronchoalveolar lavage.

    Directory of Open Access Journals (Sweden)

    Orquidea Garcia

    Full Text Available The potential for amniotic fluid stem cell (AFSC treatment to inhibit the progression of fibrotic lung injury has not been described. We have previously demonstrated that AFSC can attenuate both acute and chronic-fibrotic kidney injury through modification of the cytokine environment. Fibrotic lung injury, such as in Idiopathic Pulmonary Fibrosis (IPF, is mediated through pro-fibrotic and pro-inflammatory cytokine activity. Thus, we hypothesized that AFSC treatment might inhibit the progression of bleomycin-induced pulmonary fibrosis through cytokine modulation. In particular, we aimed to investigate the effect of AFSC treatment on the modulation of the pro-fibrotic cytokine CCL2, which is increased in human IPF patients and is correlated with poor prognoses, advanced disease states and worse fibrotic outcomes. The impacts of intravenous murine AFSC given at acute (day 0 or chronic (day 14 intervention time-points after bleomycin injury were analyzed at either day 3 or day 28 post-injury. Murine AFSC treatment at either day 0 or day 14 post-bleomycin injury significantly inhibited collagen deposition and preserved pulmonary function. CCL2 expression increased in bleomycin-injured bronchoalveolar lavage (BAL, but significantly decreased following AFSC treatment at either day 0 or at day 14. AFSC were observed to localize within fibrotic lesions in the lung, showing preferential targeting of AFSC to the area of fibrosis. We also observed that MMP-2 was transiently increased in BAL following AFSC treatment. Increased MMP-2 activity was further associated with cleavage of CCL2, rendering it a putative antagonist for CCL2/CCR2 signaling, which we surmise is a potential mechanism for CCL2 reduction in BAL following AFSC treatment. Based on this data, we concluded that AFSC have the potential to inhibit the development or progression of fibrosis in a bleomycin injury model during both acute and chronic remodeling events.

  12. Amniotic Fluid Stem Cells Inhibit the Progression of Bleomycin-Induced Pulmonary Fibrosis via CCL2 Modulation in Bronchoalveolar Lavage

    Science.gov (United States)

    Garcia, Orquidea; Carraro, Gianni; Turcatel, Gianluca; Hall, Marisa; Sedrakyan, Sargis; Roche, Tyler; Buckley, Sue; Driscoll, Barbara; Perin, Laura; Warburton, David

    2013-01-01

    The potential for amniotic fluid stem cell (AFSC) treatment to inhibit the progression of fibrotic lung injury has not been described. We have previously demonstrated that AFSC can attenuate both acute and chronic-fibrotic kidney injury through modification of the cytokine environment. Fibrotic lung injury, such as in Idiopathic Pulmonary Fibrosis (IPF), is mediated through pro-fibrotic and pro-inflammatory cytokine activity. Thus, we hypothesized that AFSC treatment might inhibit the progression of bleomycin-induced pulmonary fibrosis through cytokine modulation. In particular, we aimed to investigate the effect of AFSC treatment on the modulation of the pro-fibrotic cytokine CCL2, which is increased in human IPF patients and is correlated with poor prognoses, advanced disease states and worse fibrotic outcomes. The impacts of intravenous murine AFSC given at acute (day 0) or chronic (day 14) intervention time-points after bleomycin injury were analyzed at either day 3 or day 28 post-injury. Murine AFSC treatment at either day 0 or day 14 post-bleomycin injury significantly inhibited collagen deposition and preserved pulmonary function. CCL2 expression increased in bleomycin-injured bronchoalveolar lavage (BAL), but significantly decreased following AFSC treatment at either day 0 or at day 14. AFSC were observed to localize within fibrotic lesions in the lung, showing preferential targeting of AFSC to the area of fibrosis. We also observed that MMP-2 was transiently increased in BAL following AFSC treatment. Increased MMP-2 activity was further associated with cleavage of CCL2, rendering it a putative antagonist for CCL2/CCR2 signaling, which we surmise is a potential mechanism for CCL2 reduction in BAL following AFSC treatment. Based on this data, we concluded that AFSC have the potential to inhibit the development or progression of fibrosis in a bleomycin injury model during both acute and chronic remodeling events. PMID:23967234

  13. Extreme 13C depletion of CCl2F2 in firn air samples from NEEM, Greenland

    Directory of Open Access Journals (Sweden)

    T. Blunier

    2013-01-01

    Full Text Available A series of 12 high volume air samples collected from the S2 firn core during the North Greenland Eemian Ice Drilling (NEEM 2009 campaign have been measured for mixing ratio and stable carbon isotope composition of the chlorofluorocarbon CFC-12 (CCl2F2. While the mixing ratio measurements compare favorably to other firn air studies, the isotope results show extreme 13C depletion at the deepest measurable depth (65 m, to values lower than δ13C = −80‰ vs. VPDB (the international stable carbon isotope scale, compared to present day surface tropospheric measurements near −40‰. Firn air modeling was used to interpret these measurements. Reconstructed atmospheric time series indicate even larger depletions (to −120‰ near 1950 AD, with subsequent rapid enrichment of the atmospheric reservoir of the compound to the present day value. Mass-balance calculations show that this change is likely to have been caused by a large change in the isotopic composition of anthropogenic CFC-12 emissions, probably due to technological advances in the CFC production process over the last 80 yr, though direct evidence is lacking.

  14. Noncanonical Pathway for Regulation of CCL2 Expression by an mTORC1-FOXK1 Axis Promotes Recruitment of Tumor-Associated Macrophages

    Directory of Open Access Journals (Sweden)

    Hirokazu Nakatsumi

    2017-11-01

    Full Text Available C-C chemokine ligand 2 (CCL2 plays pivotal roles in tumor formation, progression, and metastasis. Although CCL2 expression has been found to be dependent on the nuclear factor (NF-κB signaling pathway, the regulation of CCL2 production in tumor cells has remained unclear. We have identified a noncanonical pathway for regulation of CCL2 production that is mediated by mammalian target of rapamycin complex 1 (mTORC1 but independent of NF-κB. Multiple phosphoproteomics approaches identified the transcription factor forkhead box K1 (FOXK1 as a downstream target of mTORC1. Activation of mTORC1 induces dephosphorylation of FOXK1, resulting in transactivation of the CCL2 gene. Inhibition of the mTORC1-FOXK1 axis attenuated insulin-induced CCL2 production as well as the accumulation of tumor-associated monocytes-macrophages and tumor progression in mice. Our results suggest that FOXK1 directly links mTORC1 signaling and CCL2 expression in a manner independent of NF-κB and that CCL2 produced by this pathway contributes to tumor progression.

  15. Microglia-Mediated Neuroinflammation and Neurotrophic Factor-Induced Protection in the MPTP Mouse Model of Parkinson's Disease-Lessons from Transgenic Mice.

    Science.gov (United States)

    Machado, Venissa; Zöller, Tanja; Attaai, Abdelraheim; Spittau, Björn

    2016-01-26

    Parkinson's disease (PD) is a neurodegenerative disease characterised by histopathological and biochemical manifestations such as loss of midbrain dopaminergic (DA) neurons and decrease in dopamine levels accompanied by a concomitant neuroinflammatory response in the affected brain regions. Over the past decades, the use of toxin-based animal models has been crucial to elucidate disease pathophysiology, and to develop therapeutic approaches aimed to alleviate its motor symptoms. Analyses of transgenic mice deficient for cytokines, chemokine as well as neurotrophic factors and their respective receptors in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model of PD have broadened the current knowledge of neuroinflammation and neurotrophic support. Here, we provide a comprehensive review that summarises the contribution of microglia-mediated neuroinflammation in MPTP-induced neurodegeneration. Moreover, we highlight the contribution of neurotrophic factors as endogenous and/or exogenous molecules to slow the progression of midbrain dopaminergic (mDA) neurons and further discuss the potential of combined therapeutic approaches employing neuroinflammation modifying agents and neurotrophic factors.

  16. Preliminary report on electron energy-loss measurements for CCl3, CCl2F2, CCl3F

    International Nuclear Information System (INIS)

    Bushnell, D.L. Jr.; Huebner, R.H.; Celotta, R.J.; Mielczarek, S.R.

    1975-01-01

    Currently, nation-wide research efforts are devoted to studying the possible ozone (O 3 ) depletion in the stratosphere by the chemical action of chlorine atoms released from CCl 2 F 2 or CCl 3 F upon absorption of ultraviolet radiation. Since electron-impact data taken in the forward scattering direction can be used to derive oscillator strengths and thus to yield apparent photoabsorption cross sections, such an analysis for CCl 2 F 2 , CCLl 3 F, and CClF 3 was carried out. Oscillator-strength distributions were obtained between 5 and 20 eV and are compared to available photoabsorption data. Certain photoabsorption values agree very well with these electron-impact data, but other optical studies deviate in some spectral regions by as much as a factor of 5. Also, the electron energy-loss spectrum reveals electronic transitions previously undetected by photoabsorption

  17. Equine herpesvirus type-1 modulates CCL2, CCL3, CCL5, CXCL9, and CXCL10 chemokine expression.

    Science.gov (United States)

    Wimer, Christine L; Damiani, Armando; Osterrieder, Nikolaus; Wagner, Bettina

    2011-04-15

    Equine herpesvirus type 1 (EHV-1) is highly prevalent in horses and causes rhinopneumonitis, abortion, and encephalopathy. Studies on the related human herpes simplex virus and of murine models of EHV-1 suggest that chemokines play important roles in coordinating of innate and adaptive immune responses, and thus effective control of herpesvirus infection and prevention of severe clinical disease. Here, equine peripheral blood mononuclear cells (PBMC) were infected with one of three EHV-1 strains, which differ in pathogenicity (RacL11, NY03=abortogenic, Ab4=neurogenic). Changes in CCL2, CCL3, CCL5, CXCL9 and CXCL10 chemokine gene expression relative to non-infected PBMC were measured by real-time PCR. CXCL9 and CXCL10 gene expression was up-regulated 10h post infection and decreased to the level of non-infected cells after 24h. CCL2 and CCL3 were significantly down-regulated 24h post infection with NY03 and Ab4. CCL5 was up-regulated 24h after infection with RacL11. Ab4 infected PBMC had significantly lower expression of all chemokines except CCL2 24h post infection then RacL11 infected cells. While there was not a significant difference between NY03 and the other strains, there was a trend with each chemokine toward NY03 inducing less expression then RacL11 but more then Ab4. The data suggested that EHV-1 infection of PBMC induced up-regulation of inflammatory chemokines CCL5, CXCL9 and CXCL10, and down-regulation of chemotactic CCL2 and CCL3. The data also implies that different EHV-1 strains have varying effects on all five chemokines, with the nuropathogenic strain, Ab4, having the greatest suppressive potential. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Inflammatory monocyte mobilization decreases patient survival in pancreatic cancer: a role for targeting the CCL2/CCR2 axis

    Science.gov (United States)

    Sanford, Dominic E.; Belt, Brian A.; Panni, Roheena Z.; Mayer, Allese; Deshpande, Anjali D.; Carpenter, Danielle; Mitchem, Jonathan B.; Plambeck-Suess, Stacey M.; Worley, Lori A.; Goetz, Brian D.; Wang-Gillam, Andrea; Eberlein, Timothy J.; Denardo, David G.; Goedegebuure, S. Peter; Linehan, David C.

    2013-01-01

    Purpose To determine the role of the CCL2/CCR2 axis and inflammatory monocytes (IM; CCR2+/CD14+) as immunotherapeutic targets in the treatment of pancreatic cancer (PC). Experimental Design Survival analysis was performed to determine if the prevalence of pre-operative blood monocytes correlates with survival in PC patients following tumor resection. IM prevalence in the blood and bone marrow of PC patients and controls was compared. The immunosuppressive properties of IM and macrophages in the blood and tumors, respectively, of PC patients were assessed. CCL2 expression by human PC tumors was compared to normal pancreas. A novel CCR2 inhibitor (PF-04136309) was tested in an orthotopic model of murine PC. Results Monocyte prevalence in the peripheral blood correlates inversely with survival, and low monocyte prevalence is an independent predictor of increased survival in PC patients with resected tumors. IM are increased in the blood and decreased in the bone marrow of PC patients compared to controls. An increased ratio of IM in the blood versus the bone marrow is a novel predictor of decreased patient survival following tumor resection. Human PC produces CCL2, and immunosuppressive CCR2+ macrophages infiltrate these tumors. Patients with tumors that exhibit high CCL2 expression/low CD8 T cell infiltrate have significantly decreased survival. In mice, CCR2 blockade depletes IM and macrophages from the primary tumor and premetastatic liver resulting in enhanced anti-tumor immunity, decreased tumor growth, and reduced metastasis. Conclusions IM recruitment is critical to PC progression, and targeting CCR2 may be an effective immunotherapeutic strategy in this disease. PMID:23653148

  19. Vitamin D effects on monocytes' CCL-2, IL6 and CD14 transcription in Addison's disease and HLA susceptibility.

    Science.gov (United States)

    Kraus, A U; Penna-Martinez, M; Meyer, G; Badenhoop, K

    2018-03-01

    Addison's disease is a rare autoimmune disorder leading to adrenal insufficiency and life-long glucocorticoid dependency. Vitamin D receptor (VDR) polymorphisms and vitamin D deficiency predispose to Addison's disease. Aim of the current study was, to investigate potential anti-inflammatory vitamin D effects on monocytes in Addison's disease, focusing on inflammatory CCL-2 and IL6, as well on monocyte CD14 markers. Addison's disease is genetically linked to distinct HLA susceptibility alleles. Therefore we analyzed, whether HLA genotypes differed for vitamin D effects on monocyte markers. CD14 + monocytes were isolated from Addison's disease patients (AD, n=13) and healthy controls (HC, n=15) and stimulated with 1,25-dihydroxyvitamin D 3 and IL1β as an inflammatory stimulant. Cells were processed for mRNA expression of CCL-2, IL6 and CD14 and DNA samples were genotyped for major histocompatibility class (MHC) class II-encoded HLA- DQA1-DQB1 haplotypes. We found a downregulation of CCL-2 after vitamin D treatment in IL1β-stimulated monocytes both from AD patients and HC (AD pHLA high-risk haplotypes showed an increased CCL-2 expression after IL1β-induced inflammation compared to intermediate-risk HLA carriers (p=0.05). Also HC monocytes' CD14 transcription after IL1β and vitamin D co-stimulation differed according to HLA risk profile. We show that vitamin D can exert anti-inflammatory effects on AD patients' monocytes which may be modulated by HLA risk genotypes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Tag SNP polymorphism of CCL2 and its role in clinical tuberculosis in Han Chinese pediatric population.

    Directory of Open Access Journals (Sweden)

    Wei-Xing Feng

    Full Text Available BACKGROUND: Chemokine (C-C motif ligand 2 CCL2/MCP-1 is among the key signaling molecules of innate immunity; in particular, it is involved in recruitment of mononuclear and other cells in response to infection, including tuberculosis (TB and is essential for granuloma formation. METHODOLOGY/PRINCIPAL FINDINGS: We identified a tag SNP for the CCL2/MCP-1 gene (rs4586 C/T. In order to understand whether this SNP may serve to evaluate the contribution of the CCL2 gene to the expression of TB disease, we further analysed distribution of its alleles and genotypes in 301 TB cases versus 338 non-infected controls (all BCG vaccinated representing a high-risk pediatric population of North China. In the male TB subgroup, the C allele was identified in a higher rate (P = 0.045, and, acting dominantly, was found to be a risk factor for clinical TB (P = 0.029. Homozygous TT genotype was significantly associated with lower CSF mononuclear leukocyte (ML counts in patients with tuberculous meningitis (TBM (P = 0.001. CONCLUSIONS/SIGNIFICANCE: The present study found an association of the CCL2 tag SNP rs4586 C allele and pediatric TB disease in males, suggesting that gender may affect the susceptibility to TB even in children. The association of homozygous TT genotype with decreased CSF mononuclear leukocyte (ML count not only suggests a clinical significance of this SNP, but indicates its potential to assist in the clinical assessment of suspected TBM, where delay is critical and diagnosis is difficult.

  1. Pro-Inflammatory Chemokine CCL2 (MCP-1) Promotes Healing in Diabetic Wounds by Restoring the Macrophage Response

    Science.gov (United States)

    Wood, Stephen; Jayaraman, Vijayakumar; Huelsmann, Erica J.; Bonish, Brian; Burgad, Derick; Sivaramakrishnan, Gayathri; Qin, Shanshan; DiPietro, Luisa A.; Zloza, Andrew; Zhang, Chunxiang; Shafikhani, Sasha H.

    2014-01-01

    Prior studies suggest that the impaired healing seen in diabetic wounds derives from a state of persistent hyper-inflammation characterized by harmful increases in inflammatory leukocytes including macrophages. However, such studies have focused on wounds at later time points (day 10 or older), and very little attention has been given to the dynamics of macrophage responses in diabetic wounds early after injury. Given the importance of macrophages for the process of healing, we studied the dynamics of macrophage response during early and late phases of healing in diabetic wounds. Here, we report that early after injury, the diabetic wound exhibits a significant delay in macrophage infiltration. The delay in the macrophage response in diabetic wounds results from reduced Chemokine (C-C motif) ligand 2 (CCL2) expression. Importantly, one-time treatment with chemoattractant CCL2 significantly stimulated healing in diabetic wounds by restoring the macrophage response. Our data demonstrate that, rather than a hyper-inflammatory state; the early diabetic wound exhibits a paradoxical and damaging decrease in essential macrophage response. Our studies suggest that the restoration of the proper kinetics of macrophage response may be able to jumpstart subsequent healing stages. CCL2 chemokine-based therapy may be an attractive strategy to promote healing in diabetic wounds. PMID:24618995

  2. Pro-inflammatory chemokine CCL2 (MCP-1 promotes healing in diabetic wounds by restoring the macrophage response.

    Directory of Open Access Journals (Sweden)

    Stephen Wood

    Full Text Available Prior studies suggest that the impaired healing seen in diabetic wounds derives from a state of persistent hyper-inflammation characterized by harmful increases in inflammatory leukocytes including macrophages. However, such studies have focused on wounds at later time points (day 10 or older, and very little attention has been given to the dynamics of macrophage responses in diabetic wounds early after injury. Given the importance of macrophages for the process of healing, we studied the dynamics of macrophage response during early and late phases of healing in diabetic wounds. Here, we report that early after injury, the diabetic wound exhibits a significant delay in macrophage infiltration. The delay in the macrophage response in diabetic wounds results from reduced Chemokine (C-C motif ligand 2 (CCL2 expression. Importantly, one-time treatment with chemoattractant CCL2 significantly stimulated healing in diabetic wounds by restoring the macrophage response. Our data demonstrate that, rather than a hyper-inflammatory state; the early diabetic wound exhibits a paradoxical and damaging decrease in essential macrophage response. Our studies suggest that the restoration of the proper kinetics of macrophage response may be able to jumpstart subsequent healing stages. CCL2 chemokine-based therapy may be an attractive strategy to promote healing in diabetic wounds.

  3. Assessment of CCL2 and CXCL8 chemokines in serum, bronchoalveolar lavage fluid and lung tissue samples from dogs affected with canine idiopathic pulmonary fibrosis.

    Science.gov (United States)

    Roels, Elodie; Krafft, Emilie; Farnir, Frederic; Holopainen, Saila; Laurila, Henna P; Rajamäki, Minna M; Day, Michael J; Antoine, Nadine; Pirottin, Dimitri; Clercx, Cecile

    2015-10-01

    Canine idiopathic pulmonary fibrosis (CIPF) is a progressive disease of the lung parenchyma that is more prevalent in dogs of the West Highland white terrier (WHWT) breed. Since the chemokines (C-C motif) ligand 2 (CCL2) and (C-X-C motif) ligand 8 (CXCL8) have been implicated in pulmonary fibrosis in humans, the aim of the present study was to investigate whether these same chemokines are involved in the pathogenesis of CIPF. CCL2 and CXCL8 concentrations were measured by ELISA in serum and bronchoalveolar lavage fluid (BALF) from healthy dogs and WHWTs affected with CIPF. Expression of the genes encoding CCL2 and CXCL8 and their respective receptors, namely (C-C motif) receptor 2 (CCR2) and (C-X-C motif) receptor 2 (CXCR2), was compared in unaffected lung tissue and biopsies from dogs affected with CIPF by quantitative PCR and localisation of CCL2 and CXCL8 proteins were determined by immunohistochemistry. Significantly greater CCL2 and CXCL8 concentrations were found in the BALF from WHWTs affected with CIPF, compared with healthy dogs. Significantly greater serum concentrations of CCL2, but not CXCL8, were found in CIPF-affected dogs compared with healthy WHWTs. No differences in relative gene expression for CCL2, CXCL8, CCR2 or CXCR2 were observed when comparing lung biopsies from control dogs and those affected with CIPF. In affected lung tissues, immunolabelling for CCL2 and CXCL8 was observed in bronchial airway epithelial cells in dogs affected with CIPF. The study findings suggest that both CCL2 and CXCL8 are involved in the pathogenesis of CIPF. Further studies are required to determine whether these chemokines might have a clinical use as biomarkers of fibrosis or as targets for therapeutic intervention. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Role of CCL-2, CCR-2 and CCR-4 in cerulein-induced acute pancreatitis and pancreatitis-associated lung injury.

    Science.gov (United States)

    Frossard, Jean Louis; Lenglet, Sébastien; Montecucco, Fabrizio; Steffens, Sabine; Galan, Katia; Pelli, Graziano; Spahr, Laurent; Mach, Francois; Hadengue, Antoine

    2011-05-01

    Acute pancreatitis is an inflammatory process of variable severity. Leucocytes are thought to play a key role in the development of pancreatitis and pancreatitis-associated lung injury. The interactions between inflammatory cells and their mediators are crucial for determining tissue damage. Monocyte chemoattractant protein-1 (or CCL-2), CCR-2 and CCR-4 are chemokines and chemokine receptors involved in leucocyte trafficking. The aim of the study was to evaluate the role of the CCL-2, CCR-2 and CCR-4 chemokine receptors in the pathogenesis of cerulein-induced pancreatitis and pancreatitis-associated lung injury. To address the role of CCL-2, CCR-2 and CCR-4 that attracts leucocytes cells in inflamed tissues, pancreatitis was induced by administering supramaximal doses of cerulein in mice that do not express CCL-2, CCR-2 or CCR-4. The severity of pancreatitis was measured by serum amylase, pancreatic oedema and acinar cell necrosis. Lung injury was quantitated by evaluating lung microvascular permeability and lung myeloperoxidase activity. Chemokine and chemokine-receptor expression were quantitated by real-time PCR. The nature of inflammatory cells invading the pancreas and lungs was studied by immunostaining. The authors have found that pancreas CCL-2 and CCR-2 levels rise during pancreatitis. Both pancreatitis and the associated lung injury are blunted, but not completely prevented, in mice deficient in CCL-2, whereas the deficiency in either CCR-2 or CCR-4 does not reduce the severity of both the pancreatitis and the lung injury. The amounts of neutrophils and monocyte/macrophages (MOMA)-2 cells were significantly lower in mice deficient in CCL-2 compared with their sufficient littermates. These results suggest that CCL-2 plays a key role in pancreatitis by modulating the infiltration by neutrophils and MOMA-2 cells, and that its deficiency may improve the outcome of the disease.

  5. Recombinant VP1, an Akt inhibitor, suppresses progression of hepatocellular carcinoma by inducing apoptosis and modulation of CCL2 production.

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    Tai-An Chen

    Full Text Available BACKGROUND: The application of viral elements in tumor therapy is one facet of cancer research. Recombinant capsid protein VP1 (rVP1 of foot-and-mouth disease virus has previously been demonstrated to induce apoptosis in cancer cell lines. Here, we aim to further investigate its apoptotic mechanism and possible anti-metastatic effect in murine models of hepatocellular carcinoma (HCC, one of the most common human cancers worldwide. METHODOLOGY/PRINCIPAL FINDINGS: Treatment with rVP1 inhibited cell proliferation in two murine HCC cell lines, BNL and Hepa1-6, with IC₅₀ values in the range of 0.1-0.2 µM. rVP1 also induced apoptosis in these cells, which was mediated by Akt deactivation and dissociation of Ku70-Bax, and resulted in conformational changes and mitochondrial translocation of Bax, leading to the activation of caspases-9, -3 and -7. Treatment with 0.025 µM rVP1, which did not affect the viability of normal hepatocytes, suppressed cell migration and invasion via attenuating CCL2 production. The production of CCL2 was modulated by Akt-dependent NF-κB activation that was decreased after rVP1 treatment. The in vivo antitumor effects of rVP1 were assessed in both subcutaneous and orthotopic mouse models of HCC in immune-competent BALB/c mice. Intratumoral delivery of rVP1 inhibited subcutaneous tumor growth as a result of increased apoptosis. Intravenous administration of rVP1 in an orthotopic HCC model suppressed tumor growth, inhibited intra-hepatic metastasis, and prolonged survival. Furthermore, a decrease in the serum level of CCL2 was observed in rVP1-treated mice. CONCLUSIONS/SIGNIFICANCE: The data presented herein suggest that, via inhibiting Akt phosphorylation, rVP1 suppresses the growth, migration, and invasion of murine HCC cells by inducing apoptosis and attenuating CCL2 production both in vitro and in vivo. Recombinant protein VP1 thus has the potential to be developed as a new therapeutic agent for HCC.

  6. Dihydroisotanshinone I combined with radiation inhibits the migration ability of prostate cancer cells through DNA damage and CCL2 pathway.

    Science.gov (United States)

    Lee, I-Yun; Lin, Yin-Yin; Yang, Yao-Hsu; Lin, Yu-Shin; Lin, Chun-Liang; Lin, Wei-Yu; Cheng, Yu-Ching; Shu, Li-Hsin; Wu, Ching-Yuan

    2018-01-31

    Radiotherapy plays an important role in the treatment of prostate cancer. Despite that sophisticated techniques of radiotherapy and radiation combined with chemotherapy were applied to the patients, some tumors may recur. Therefore, the study investigated the effect of dihydroisotanshinone I (DT) and the combination treatment of 5 μM DT and 5Gy irradiation (IR) against the migration ability of prostate cancer cells. DT and the combination treatment were studied for its biological activity against migration ability of prostate cancer cells with transwell migration assay. Subsequently, we tried to explore the underlying mechanism with ELISA, flow cytometry and Western's blotting assay. The results showed that DT and the combination treatment substantially inhibited the migration ability of prostate cancer cells. DT and the combined treatment can decrease the ability of macrophages to recruit prostate cancer cells. Mechanistically, DT and the combination treatment reduced the secretion of chemokine (C-C Motif) Ligand 2 (CCL2) from prostate cancer cells. We also found that DT treatment induced the cell cycle of prostate cancer cells entering S phase and increased the protein expression of DNA damage response proteins (rH2AX and phosphorylated ataxia telangiectasia-mutated [ATM]) in DU145 cells and PC-3 cells. DT displays radiosensitization and antimigration effects in prostate cancer cells by inducing DNA damage and inhibiting CCL2 secretion. We suggest that DT can be used as a novel antimetastatic cancer drug or radiosensitizer in the armamentarium of prostate cancer management.

  7. The Ca2+ activated SK3 channel is expressed in microglia in the rat striatum and contributes to microglia-mediated neurotoxicity in vitro

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    Kaushal Vikas

    2010-01-01

    Full Text Available Abstract Background Small-conductance Ca2+ activated K+ channels are expressed in the CNS, where KCNN2/SK2/KCa2.2 and KCNN3/SK3/KCa2.3 help shape the electrical activity of some neurons. The SK3 channel is considered a potential therapeutic target for diseases and disorders involving neuron hyper-excitability but little is known about its expression and roles in non-neuronal cells in either the healthy or damaged CNS. The purpose of this study was to examine expression of KCNN3/SK3 in CNS microglia in vivo and in vitro, and to use an established in vitro model to determine if this channel contributes to the neurotoxic capacity of activated microglia. Methods KCNN3 mRNA (real-time RT-PCR and SK3 immunoreactivity were examined in rat microglia. Lipopolysaccharide was then used to activate microglia (monitored by iNOS, nitric oxide, activation of NF-κB and p38 MAPK and transform them to a neurotoxic state. Microglia-mediated neuron damage (TUNEL, activated caspase 3 and nitrotyrosine levels were quantified using a two-chamber system that allowed microglia to be treated with channel blockers, washed and then added to neuron/astrocyte cultures. Contributions of SK3 to these processes were discriminated using a subtractive pharmacological approach with apamin and tamapin. ANOVA and post-hoc tests were used to assess the statistical significance of differences between treatment groups. SK3 immunoreactivity was then compared in the normal and damaged adult rat striatum, by injecting collagenase (a hemorrhagic stroke or endothelin-1 (a transient ischemic stroke. Results KCNN3 mRNA was prevalent in cultured microglia and increased after lipopolysaccharide-induced activation; SK3 channel blockade inhibited microglial activation and reduced their ability to kill neurons. SK3 immunoreactivity was prevalent in cultured microglia and throughout the adult rat striatum (except white matter tracts. After strokes, SK3 was highly expressed in activated microglia

  8. CCL2 as a trigger of manifestations of compensatory anti-inflammatory response syndrome in mice with severe systemic inflammatory response syndrome.

    Science.gov (United States)

    Takahashi, Hitoshi; Tsuda, Yasuhiro; Kobayashi, Makiko; Herndon, David N; Suzuki, Fujio

    2006-04-01

    Patients with compensatory anti-inflammatory response syndrome (CARS) are at a higher risk for infection with various opportunistic pathogens. CARS develops commonly in association with the manifestation of systemic inflammatory response syndrome (SIRS). In the present study, the role of SIRS-associated soluble factors on the CARS development was examined in mice with pancreatitis, a carrier of typical SIRS. Following the production of SIRS-related cytokines [tumor necrosis factor alpha and interleukin (IL)-1beta], CC chemokine ligand 2 (CCL2), IL-4, and IL-10 (typical CARS cytokines) were detected in the sera of mice with pancreatitis. CCL2 has been described as an essential chemokine for the T helper cell type 2 manifestation. CARS effector cells (cells with an ability to produce IL-4 and IL-10) were not generated from normal T cells after stimulation with SIRS-related cytokines. However, these cells were generated from normal T cells after cultivation with peripheral blood neutrophils (PMN) from SIRS mice in a dual-chamber transwell. Normal T cells did not convert to CARS effector cells after transwell cultures with PMN from normal mice. CCL2 was detected in culture fluids of PMN from SIRS mice, and PMN from normal mice did not produce CCL2 into their culture fluids. CARS effector cells did not appear in PMN-depleted SIRS mice or SIRS mice treated with anti-CCL2 monoclonal antibody, and these cells were demonstrated in PMN-depleted SIRS mice after treatment with recombinant murine CCL2. These results indicate that CCL2 produced by PMN from SIRS mice is an active molecule on the SIRS-associated CARS manifestation.

  9. Spinal CCL2 Promotes Central Sensitization, Long-Term Potentiation, and Inflammatory Pain via CCR2: Further Insights into Molecular, Synaptic, and Cellular Mechanisms.

    Science.gov (United States)

    Xie, Rou-Gang; Gao, Yong-Jing; Park, Chul-Kyu; Lu, Ning; Luo, Ceng; Wang, Wen-Ting; Wu, Sheng-Xi; Ji, Ru-Rong

    2018-02-01

    Mounting evidence supports an important role of chemokines, produced by spinal cord astrocytes, in promoting central sensitization and chronic pain. In particular, CCL2 (C-C motif chemokine ligand 2) has been shown to enhance N-methyl-D-aspartate (NMDA)-induced currents in spinal outer lamina II (IIo) neurons. However, the exact molecular, synaptic, and cellular mechanisms by which CCL2 modulates central sensitization are still unclear. We found that spinal injection of the CCR2 antagonist RS504393 attenuated CCL2- and inflammation-induced hyperalgesia. Single-cell RT-PCR revealed CCR2 expression in excitatory vesicular glutamate transporter subtype 2-positive (VGLUT2 + ) neurons. CCL2 increased NMDA-induced currents in CCR2 + /VGLUT2 + neurons in lamina IIo; it also enhanced the synaptic NMDA currents evoked by dorsal root stimulation; and furthermore, it increased the total and synaptic NMDA currents in somatostatin-expressing excitatory neurons. Finally, intrathecal RS504393 reversed the long-term potentiation evoked in the spinal cord by C-fiber stimulation. Our findings suggest that CCL2 directly modulates synaptic plasticity in CCR2-expressing excitatory neurons in spinal lamina IIo, and this underlies the generation of central sensitization in pathological pain.

  10. Metalloproteinases control brain inflammation induced by pertussis toxin in mice overexpressing the chemokine CCL2 in the central nervous system

    DEFF Research Database (Denmark)

    Toft-Hansen, Henrik; Buist, Richard; Sun, Xue-Jun

    2006-01-01

    in the perivascular space in brains of transgenic (Tg) mice that overexpress CCL2 under control of a CNS-specific promoter. The Tg mice show no clinical symptoms, even though leukocytes have crossed the endothelial basement membrane. Pertussis toxin (PTx) given i.p. induced encephalopathy and weight loss in Tg mice...... symptoms. Metalloproteinase (MPs) enzymes are implicated in leukocyte infiltration in neuroinflammation. Unmanipulated Tg mice had elevated expression of tissue inhibitor of metalloproteinase-1, matrix metalloproteinase (MMP)-10, and -12 mRNA in the brain. PTx further induced expression of tissue inhibitor...... of metalloproteinase-1, metalloproteinase disintegrins-12, MMP-8, and -10 in brains of Tg mice. Levels of the microglial-associated MP MMP-15 were not affected in control or PTx-treated Tg mice. PTx also up-regulated expression of proinflammatory cytokines IL-1beta and TNF-alpha mRNA in Tg CNS. Weight loss...

  11. Smac Mimetic-Induced Upregulation of CCL2/MCP-1 Triggers Migration and Invasion of Glioblastoma Cells and Influences the Tumor Microenvironment in a Paracrine Manner

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    Carina Lindemann

    2015-06-01

    Full Text Available Second mitochondria-derived activator of caspase (Smac mimetics are considered as promising anticancer therapeutics that are currently under investigation in early clinical trials. They induce apoptosis by antagonizing inhibitor of apoptosis proteins, which are frequently overexpressed in cancer. We previously reported that Smac mimetics, such as BV6, additionally exert non-apoptotic functions in glioblastoma (GBM cells by stimulating migration and invasion in a nuclear factor kappa B (NF-κB-dependent manner. Because NF-κB target genes mediating these effects are largely unknown, we performed whole-genome expression analyses. Here, we identify chemokine (C-C motif ligand 2 (CCL2 as the top-listed NF-κB-regulated gene being upregulated upon BV6 treatment in GBM cells. BV6-induced upregulation and secretion of CCL2 are required for migration and invasion of GBM cells because knockdown of CCL2 in GBM cells abolishes these effects. Co-culture experiments of GBM cells with non-malignant astroglial cells reveal that BV6-stimulated secretion of CCL2 by GBM cells into the supernatant triggers migration of astroglial cells toward GBM cells because CCL2 knockdown in BV6-treated GBM cells impedes BV6-stimulated migration of astroglial cells. In conclusion, we identify CCL2 as a BV6-induced NF-κB target gene that triggers migration and invasion of GBM cells and exerts paracrine effects on the GBM's microenvironment by stimulating migration of astroglial cells. These findings provide novel insights into the biological functions of Smac mimetics with important implications for the development of Smac mimetics as cancer therapeutics.

  12. Estrogen-dependent regulation of human uterine natural killer cells promotes vascular remodelling via secretion of CCL2.

    Science.gov (United States)

    Gibson, D A; Greaves, E; Critchley, H O D; Saunders, P T K

    2015-06-01

    Does intrauterine biosynthesis of estrogen play an important role in early pregnancy by altering the function of uterine natural killer (uNK) cells? Estrogens directly regulate the function of human uNK cells by increasing uNK cell migration and secretion of uNK cell-derived chemokine (C-C motif) ligand 2 (CCL2) that critically facilitates uNK-mediated angiogenesis. uNK cells are a phenotypically distinct population of tissue-resident immune cells that regulate vascular remodelling within the endometrium and decidua. Recently we discovered that decidualisation of human endometrial stromal cells results in the generation of an estrogen-rich microenvironment in areas of decidualised endometrium. We hypothesize that intrauterine biosynthesis of estrogens plays an important role in early pregnancy by altering the function of uNK cells. This laboratory-based study used primary human uNK cells which were isolated from first trimester human decidua (n = 32). Primary uNK cells were isolated from first trimester human decidua using magnetic cell sorting. The impact of estrogens on uNK cell function was assessed. Isolated uNK cells were treated with estrone (E1, 10(-8) M) or estradiol (E2, 10(-8) M) alone or in combination with the anti-estrogen ICI 182 780 (ICI, 10(-6) M). uNK cell motility was assessed by transwell migration assay and time-lapse microscopy. Expression of chemokine receptors was assessed by quantitative PCR (qPCR) and immunohistochemistry, and angiogenic factors were assessed by qPCR and cytokine array. Concentrations of CCL2 in supernatants were measured by enzyme-linked immunosorbent assay. Angiogenesis was assessed in a human endometrial endothelial cell network formation assay. Treatment with either E1 or E2 increased uNK cell migration (P = 0.0092 and P = 0.0063, respectively) compared with control. Co-administration of the anti-estrogen ICI blocked the effects of E1 and E2 on cell migration. Concentrations of C-X-C chemokine receptor type 4 (CXCR4) m

  13. Evaluation of the Effects of Some Brazilian Medicinal Plants on the Production of TNF- α and CCL2 by THP-1 Cells.

    Science.gov (United States)

    Gusman, Grasielle S; Campana, Priscilla R V; Castro, Luciano C; Castilho, Rachel O; Teixeira, Mauro M; Braga, Fernão C

    2015-01-01

    Several plant species are traditionally used in Brazil to treat various inflammatory diseases. Tumor necrosis factor- (TNF-) α and chemokine (C-C motif) ligand 2 (CCL2) are key inflammatory mediators in diseases like rheumatoid arthritis and atherosclerosis, respectively; nevertheless, only a few extracts have been assayed against these targets. We herein report the effect of 19 plant extracts on TNF-α and CCL2 release by lipopolysaccharide- (LPS-) stimulated THP-1 cells, a human monocytic leukemia cell line, along with their radical scavenging activity on DPPH. The extracts of Caryocar brasiliense, Casearia sylvestris, Coccoloba cereifera, and Terminalia glabrescens inhibited TNF-α production in a concentration-dependent manner. Fractionation of these extracts potentiated the anti-TNF-α effect, which was shown to concentrate in polar fractions, mainly composed by polyphenols. Significant CCL2 inhibition was elicited by Lippia sidoides and Terminalia glabrescens extracts, whose fractionation resulted in highly active low polar fractions. All assayed extracts showed strong radical scavenging activity, but antioxidant activity did not correlate with inhibition of TNF-α or CCL2 production. Our results allowed identifying extracts with selective capacity to block cytokine production; therefore, further purification of these extracts may yield molecules that could be useful in the treatment of chronic inflammatory diseases.

  14. Chemokine MCP1/CCL2 and RANTES/CCL5 gene polymorphisms influence Henoch–Schönlein purpura susceptibility and severity

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    Hsin-Hui Yu

    2015-04-01

    Conclusion: Our results support the fact that chemokines play important roles in the pathogenesis of HSP. MCP1/CCL2 gene polymorphisms were associated with susceptibility for HSP. RANTES/CCL5 gene polymorphisms may be related to disease severity and HSP nephritis.

  15. Evaluation of the Effects of Some Brazilian Medicinal Plants on the Production of TNF-α and CCL2 by THP-1 Cells

    Directory of Open Access Journals (Sweden)

    Grasielle S. Gusman

    2015-01-01

    Full Text Available Several plant species are traditionally used in Brazil to treat various inflammatory diseases. Tumor necrosis factor- (TNF- α and chemokine (C-C motif ligand 2 (CCL2 are key inflammatory mediators in diseases like rheumatoid arthritis and atherosclerosis, respectively; nevertheless, only a few extracts have been assayed against these targets. We herein report the effect of 19 plant extracts on TNF-α and CCL2 release by lipopolysaccharide- (LPS- stimulated THP-1 cells, a human monocytic leukemia cell line, along with their radical scavenging activity on DPPH. The extracts of Caryocar brasiliense, Casearia sylvestris, Coccoloba cereifera, and Terminalia glabrescens inhibited TNF-α production in a concentration-dependent manner. Fractionation of these extracts potentiated the anti-TNF-α effect, which was shown to concentrate in polar fractions, mainly composed by polyphenols. Significant CCL2 inhibition was elicited by Lippia sidoides and Terminalia glabrescens extracts, whose fractionation resulted in highly active low polar fractions. All assayed extracts showed strong radical scavenging activity, but antioxidant activity did not correlate with inhibition of TNF-α or CCL2 production. Our results allowed identifying extracts with selective capacity to block cytokine production; therefore, further purification of these extracts may yield molecules that could be useful in the treatment of chronic inflammatory diseases.

  16. Dendritic cell CNS recruitment correlates with disease severity in EAE via CCL2 chemotaxis at the blood–brain barrier through paracellular transmigration and ERK activation

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    Sagar Divya

    2012-10-01

    Full Text Available Abstract Background Transmigration of circulating dendritic cells (DCs into the central nervous system (CNS across the blood–brain barrier (BBB has not thus far been investigated. An increase in immune cell infiltration across the BBB, uncontrolled activation and antigen presentation are influenced by chemokines. Chemokine ligand 2 (CCL2 is a potent chemoattractant known to be secreted by the BBB but has not been implicated in the recruitment of DCs specifically at the BBB. Methods Experimental autoimmune encephalomyelitis (EAE was induced in C57BL/6 mice by injection of MOG35–55 peptide and pertussis toxin intraperitoneally. Animals with increasing degree of EAE score were sacrificed and subjected to near-infrared and fluorescence imaging analysis to detect and localize the accumulation of CD11c+-labeled DCs with respect to CCL2 expression. To further characterize the direct effect of CCL2 in DC trafficking at the BBB, we utilized an in vitro BBB model consisting of human brain microvascular endothelial cells to compare migratory patterns of monocyte-derived dendritic cells, CD4+ and CD8+ T cells. Further, this model was used to image transmigration using fluorescence microcopy and to assess specific molecular signaling pathways involved in transmigration. Results Near-infrared imaging of DC transmigration correlated with the severity of inflammation during EAE. Ex vivo histology confirmed the presence of CCL2 in EAE lesions, with DCs emerging from perivascular spaces. DCs exhibited more efficient transmigration than T cells in BBB model studies. These observations correlated with transwell imaging, which indicated a paracellular versus transcellular pattern of migration by DCs and T cells. Moreover, at the molecular level, CCL2 seems to facilitate DC transmigration in an ERK1/2-dependent manner. Conclusion CNS recruitment of DCs correlates with disease severity in EAE via CCL2 chemotaxis and paracellular transmigration across the BBB

  17. Increase in chemokines CXCL10 and CCL2 in blood from pigs infected with high compared to low virulence African swine fever virus isolates.

    Science.gov (United States)

    Fishbourne, Emma; Hutet, Evelyne; Abrams, Charles; Cariolet, Roland; Le Potier, Marie-Frédérique; Takamatsu, Haru-H; Dixon, Linda K

    2013-10-01

    Modulation of the expression of chemokines and chemokine receptors in whole blood was compared following infection of pigs with high and low virulence isolates of African swine fever virus. Levels of mRNAs for CCL2, CCL3L1, CCL4, CXCL10, CCR1 and CCR5 were significantly increased in at least one time point following infection in two experiments and CCL5, CCR9 and CXCR4 mRNA were significantly increased in one of the experiments. The results showed that greatest fold increases in mRNAs for CXCL10 and CCL2 were observed following infection of pigs. CXCL10 mRNA was increased by up to 15 fold in infected compared to uninfected pigs. CXCL10 protein was also detected in serum from pigs infected with the high virulence Benin 97/1 isolate. Levels of CCL2 mRNA were increased in pigs infected with high virulence Benin 97/1 isolate compared to low virulence OURT88/3 isolate and this correlated with an increase of greater than 30 fold in levels of CCL2 protein detected in serum from pigs infected with this isolate. An increase in overall chemotaxis active compounds in defibrinated plasma samples from Benin 97/1 infected pigs was observed at 3 days post-infection (dpi) and a decrease by 7 dpi as measured by chemotaxis assay using normal pig leucocytes in vitro. Increased levels of CXCL10 may either contribute to the activation of lymphocyte priming toward the Th1 phenotype or induction of T lymphocyte apoptosis. Increased levels of CCL2, a chemoattractant for macrophages, may result in increased recruitment of monocytes from bone marrow thus increasing the pool of cells susceptible to infection.

  18. Accelerators

    CERN Multimedia

    CERN. Geneva

    2001-01-01

    The talk summarizes the principles of particle acceleration and addresses problems related to storage rings like LEP and LHC. Special emphasis will be given to orbit stability, long term stability of the particle motion, collective effects and synchrotron radiation.

  19. Significance of CCL2, CCL5 and CCR2 polymorphisms for adverse prognosis of Japanese encephalitis from an endemic population of India.

    Science.gov (United States)

    Chowdhury, Purvita; Khan, Siraj Ahmed

    2017-10-20

    Japanese encephalitis (JE) is a major contributor for viral encephalitis in Asia. Vaccination programme has limited success for largely populated JE endemic countries like India and disease exposure is unavoidable. Involvement of chemokines and its co-receptors for adverse prognosis of JE have been documented both in vitro and in vivo. Identification of the genetic predisposing factor for JE infection in humans is crucial but not yet established. Therefore, we investigated the association of single nucleotide polymorphisms (SNPs) in chemokines (CCL2 and CCL5) and its co-receptors (CCR2 and CCR5) with their protein level for JE. The study enrolled 87 symptomatic JE cases (mild: severe = 24:63) and 94 asymptomatic controls. Our study demonstrated that CCL2 (rs1024611G), CCL5 (rs2280788G) and CCR2 (rs1799864A) significantly associated with JE (Odds ratio = 1.63, 2.95 and 2.62, respectively and P = 0.045, P = 0.05 and P = 0.0006, respectively). The study revealed that rs1024611G allele was associated with elevated level of CCL2. CCL5 elevation associated with JE mortality having a Cox proportional hazard of 1.004 (P = 0.033). In conclusion, SNPs of chemokine viz. CCL2 (rs1024611G) and its receptor CCR2 (rs1799864A) significantly associated with JE which may serve as possible genetic predisposing factor and CCL5 protein level may act as marker for disease survival.

  20. Mesenchymal stem cells encapsulated into biomimetic hydrogel scaffold gradually release CCL2 chemokine in situ preserving cytoarchitecture and promoting functional recovery in spinal cord injury.

    Science.gov (United States)

    Papa, S; Vismara, I; Mariani, A; Barilani, M; Rimondo, S; De Paola, M; Panini, N; Erba, E; Mauri, E; Rossi, F; Forloni, G; Lazzari, L; Veglianese, P

    2018-04-03

    Spinal cord injury (SCI) is an acute neurodegenerative disorder caused by traumatic damage of the spinal cord. The neuropathological evolution of the primary trauma involves multifactorial processes that exacerbate the pathology, worsening the neurodegeneration and limiting neuroregeneration. This complexity suggests that multi-therapeutic approaches, rather than any single treatment, might be more effective. Encouraging preclinical results indicate that stem cell-based treatments may improve the disease outcome due to their multi-therapeutic ability. Mesenchymal Stem Cells (MSCs) are currently considered one of the most promising approaches. Significant improvement in the behavioral outcome after MSC treatment sustained by hydrogel has been demonstrated. However, it is still not known how hydrogel contribute to the delivery of factors secreted from MSCs and what factors are released in situ. Among different mediators secreted by MSCs after seeding into hydrogel, we have found CCL2 chemokine, which could account for the neuroprotective mechanisms of these cells. CCL2 secreted from human MSCs is delivered efficaciously in the lesioned spinal cord acting not only on recruitment of macrophages, but driving also their conversion to an M2 neuroprotective phenotype. Surprisingly, human CCL2 delivered also plays a key role in preventing motor neuron degeneration in vitro and after spinal cord trauma in vivo, with a significant improvement of the motor performance of the rodent SCI models. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. Profile of circulating levels of IL-1Ra, CXCL10/IP-10, CCL4/MIP-1β and CCL2/MCP-1 in dengue fever and parvovirosis

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    Luzia Maria de-Oliveira-Pinto

    2012-02-01

    Full Text Available Dengue virus (DENV and parvovirus B19 (B19V infections are acute exanthematic febrile illnesses that are not easily differentiated on clinical grounds and affect the paediatric population. Patients with these acute exanthematic diseases were studied. Fever was more frequent in DENV than in B19V-infected patients. Arthritis/arthralgias with DENV infection were shown to be significantly more frequent in adults than in children. The circulating levels of interleukin (IL-1 receptor antagonist (Ra, CXCL10/inducible protein-10 (IP-10, CCL4/macrophage inflammatory protein-1 beta and CCL2/monocyte chemotactic protein-1 (MCP-1 were determined by multiplex immunoassay in serum samples obtained from B19V (37 and DENV-infected (36 patients and from healthy individuals (7. Forward stepwise logistic regression analysis revealed that circulating CXCL10/IP-10 tends to be associated with DENV infection and that IL-1Ra was significantly associated with DENV infection. Similar analysis showed that circulating CCL2/MCP-1 tends to be associated with B19V infection. In dengue fever, increased circulating IL-1Ra may exert antipyretic actions in an effort to counteract the already increased concentrations of IL-1β, while CXCL10/IP-10 was confirmed as a strong pro-inflammatory marker. Recruitment of monocytes/macrophages and upregulation of the humoral immune response by CCL2/MCP-1 by B19V may be involved in the persistence of the infection. Children with B19V or DENV infections had levels of these cytokines similar to those of adult patients.

  2. CX3CL1/CX3CR1 and CCL2/CCR2 Chemokine/Chemokine Receptor Complex in Patients with AMD

    DEFF Research Database (Denmark)

    Falk, Mads Krüger; Singh, Amardeep; Faber, Carsten

    2014-01-01

    PURPOSE: The chemokine receptors CX3CR1 and CCR2 have been implicated in the development of age-related macular degeneration (AMD). The evidence is mainly derived from experimental cell studies and murine models of AMD. The purpose of this study was to investigate the association between expression...... of CX3CR1 and CCR2 on different leukocyte subsets and AMD. Furthermore we measured the plasma levels of ligands CX3CL1 and CCL2. METHODS: Patients attending our department were asked to participate in the study. The diagnosis of AMD was based on clinical examination and multimodal imaging techniques...... positive correlation between CCR2 and CX3CR1 expression on CD8+ cells (r = 0.727, p = 0.0001). We found no difference in plasma levels of CX3CL1 and CCL2 among the groups. CONCLUSIONS: Our results show a down regulation of CX3CR1 on CD8+ cells; this correlated to a low expression of CCR2 on CD8+ cells...

  3. Rhizoma coptidis Inhibits LPS-Induced MCP-1/CCL2 Production in Murine Macrophages via an AP-1 and NFB-Dependent Pathway

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    Andrew Remppis

    2010-01-01

    Full Text Available Introduction. The Chinese extract Rhizoma coptidis is well known for its anti-inflammatory, antioxidative, antiviral, and antimicrobial activity. The exact mechanisms of action are not fully understood. Methods. We examined the effect of the extract and its main compound, berberine, on LPS-induced inflammatory activity in a murine macrophage cell line. RAW 264.7 cells were stimulated with LPS and incubated with either Rhizoma coptidis extract or berberine. Activation of AP-1 and NFB was analyzed in nuclear extracts, secretion of MCP-1/CCL2 was measured in supernatants. Results. Incubation with Rhizoma coptidis and berberine strongly inhibited LPS-induced monocyte chemoattractant protein (MCP-1 production in RAW cells. Activation of the transcription factors AP-1 and NFB was inhibited by Rhizoma coptidis in a dose- and time-dependent fashion. Conclusions. Rhizoma coptidis extract inhibits LPS-induced MCP-1/CCL2 production in vitro via an AP-1 and NFB-dependent pathway. Anti-inflammatory action of the extract is mediated mainly by its alkaloid compound berberine.

  4. Rhizoma Coptidis Inhibits LPS-Induced MCP-1/CCL2 Production in Murine Macrophages via an AP-1 and NFκB-Dependent Pathway

    Science.gov (United States)

    Remppis, Andrew; Bea, Florian; Greten, Henry Johannes; Buttler, Annette; Wang, Hongjie; Zhou, Qianxing; Preusch, Michael R.; Enk, Ronny; Ehehalt, Robert; Katus, Hugo; Blessing, Erwin

    2010-01-01

    Introduction. The Chinese extract Rhizoma coptidis is well known for its anti-inflammatory, antioxidative, antiviral, and antimicrobial activity. The exact mechanisms of action are not fully understood. Methods. We examined the effect of the extract and its main compound, berberine, on LPS-induced inflammatory activity in a murine macrophage cell line. RAW 264.7 cells were stimulated with LPS and incubated with either Rhizoma coptidis extract or berberine. Activation of AP-1 and NFκB was analyzed in nuclear extracts, secretion of MCP-1/CCL2 was measured in supernatants. Results. Incubation with Rhizoma coptidis and berberine strongly inhibited LPS-induced monocyte chemoattractant protein (MCP)-1 production in RAW cells. Activation of the transcription factors AP-1 and NFκB was inhibited by Rhizoma coptidis in a dose- and time-dependent fashion. Conclusions. Rhizoma coptidis extract inhibits LPS-induced MCP-1/CCL2 production in vitro via an AP-1 and NFκB-dependent pathway. Anti-inflammatory action of the extract is mediated mainly by its alkaloid compound berberine. PMID:20652055

  5. Sesquiterpene dimer (DSF-52) from Artemisia argyi inhibits microglia-mediated neuroinflammation via suppression of NF-κB, JNK/p38 MAPKs and Jak2/Stat3 signaling pathways.

    Science.gov (United States)

    Zeng, Ke-Wu; Wang, Shu; Dong, Xin; Jiang, Yong; Tu, Peng-Fei

    2014-02-15

    Microglia-involved neuroinflammation is thought to promote brain damage in various neurodegenerative disorders. Therefore, novel therapeutics suppressing microglia over-activation could prove useful for neuroprotection in inflammation-mediated neurodegenerative diseases. DSF-52 is a novel sesquiterpene dimer compound isolated from medical plant Artemisia argyi by our group. In this study, we investigated whether DSF-52 inhibited the neuroinflammatory responses in lipopolysaccharide (LPS)-activated microglia. Our findings showed that DSF-52 inhibited the production of nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α), as well as mRNA expression of inducible nitric oxide synthase (iNOS), cyclooxygenase 2 (COX-2), interleukin-1β (IL-1β), granulocyte-macrophage colony-stimulating factor (GM-CSF) and macrophage inflammatory protein-1α (MIP-1α) in LPS-activated BV-2 microglia. Moreover, DSF-52 markedly up-regulated mRNA levels of anti-inflammatory cytokine IL-10. Mechanism study indicated that DSF-52 suppressed Akt/IκB/NF-κB inflammation pathway against LPS treatment. Also, DSF-52 down-regulated the phosphorylation levels of JNK and p38 MAPKs, but not ERK. Furthermore, DSF-52 blocked Jak2/Stat3 dependent inflammation pathway through inhibiting Jak2 and Stat3 phosphorylation, as well as Stat3 nuclear translocation. We concluded that the inhibitory ability of DSF-52 on microglia-mediated neuroinflammation may offer a novel neuroprotective modality and could be potentially useful in inflammation-mediated neurodegenerative diseases. Copyright © 2013 Elsevier GmbH. All rights reserved.

  6. The innate immune response to lower respiratory tract E. Coli infection and the role of the CCL2-CCR2 axis in neonatal mice.

    Science.gov (United States)

    McGrath-Morrow, Sharon A; Ndeh, Roland; Collaco, Joseph M; Poupore, Amy K; Dikeman, Dustin; Zhong, Qiong; Singer, Benjamin D; D'Alessio, Franco; Scott, Alan

    2017-09-01

    Neonates have greater morbidity/mortality from lower respiratory tract infections (LRTI) compared to older children. Lack of conditioning of the pulmonary immune system due to limited environmental exposures and/or infectious challenges likely contributes to the increase susceptibility in the neonate. In this study, we sought to gain insights into the nature and dynamics of the neonatal pulmonary immune response to LRTI using a murine model. Wildtype (WT) and Ccr2 -/- C57BL/6 neonatal and juvenile mice received E. coli or PBS by direct pharyngeal aspiration. Flow cytometry was used to measure immune cell dynamics and identify cytokine-producing cells. Real-time PCR and ELISA were used to measure cytokine/chemokine expression. Innate immune cell recruitment in response to E. coli-induced LRTI was delayed in the neonatal lung compared to juvenile lung. Lung clearance of bacteria was also significantly delayed in the neonate. Ccr2 -/- neonates, which lack an intact CCL2-CCR2 axis, had higher mortality after E. coli challenged than Ccr2 +/+ neonates. A greater percentage of CD8 + T cells and monocytes from WT neonates challenged with E. coli produced TNF compared to controls. The pulmonary immune response to E. coli-induced LRTI differed significantly between neonatal and juvenile mice. Neonates were more susceptible to increasing doses of E. coli and exhibited greater mortality than juveniles. In the absence of an intact CCL2-CCR2 axis, susceptibility to LRTI-induced mortality was further increased in neonatal mice. Taken together these findings underscore the importance of age-related differences in the innate immune response to LRTI during early stages of postnatal life. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Pleiotrophin regulates microglia-mediated neuroinflammation.

    Science.gov (United States)

    Fernández-Calle, Rosalía; Vicente-Rodríguez, Marta; Gramage, Esther; Pita, Jimena; Pérez-García, Carmen; Ferrer-Alcón, Marcel; Uribarri, María; Ramos, María P; Herradón, Gonzalo

    2017-03-04

    Pleiotrophin (PTN) is a cytokine found highly upregulated in the brain in different disorders characterized by overt neuroinflammation such as neurodegenerative diseases, drug addiction, traumatic injury, and ischemia. In the present work, we have explored whether PTN modulates neuroinflammation and if Toll-like receptor 4 (TLR4), crucial in the initiation of an immune response, is involved. In immunohistochemistry assays, we studied lipopolysaccharide (LPS, 7.5 mg/kg i.p.)-induced changes in glial fibrillary acidic protein (GFAP, astrocyte marker) and ionized calcium-binding adaptor molecule 1 (Iba1, microglia marker) expression in the prefrontal cortex (PFC) and striatum of mice with transgenic PTN overexpression in the brain (PTN-Tg) and in wild-type (WT) mice. Cytokine protein levels were assessed in the PFC by X-MAP technology. The influence of TLR4 signaling in LPS effects in both genotypes was assessed by pretreatment with the TLR4 antagonist (TAK-242, 3.0 mg/kg i.p.). Murine BV2 microglial cells were treated with PTN (0.5 μg/ml) and LPS (1.0 μg/ml) and assessed for the release of nitric oxide (NO). We found that LPS-induced microglial activation is significantly increased in the PFC of PTN-Tg mice compared to that of WT mice. The levels of TNF-α, IL-6, and MCP-1 in response to LPS were significantly increased in the PFC of PTN-Tg mice compared to that of WT mice. Pretreatment with TAK-242 efficiently blocked increases in cytokine contents in a similar manner in both genotypes. Concomitant incubation of BV2 cells with LPS and PTN significantly potentiated the production of NO compared to cells only treated with LPS. Our findings identify for the first time that PTN is a novel and potent regulator of neuroinflammation. Pleiotrophin potentiates LPS-stimulated microglia activation. Our results suggest that regulation of the PTN signaling pathways may constitute new therapeutic opportunities particularly in those neurological disorders characterized by increased PTN cerebral levels and neuroinflammation.

  8. Prophylactic Subacute Administration of Zinc Increases CCL2, CCR2, FGF2, and IGF-1 Expression and Prevents the Long-Term Memory Loss in a Rat Model of Cerebral Hypoxia-Ischemia

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    Victor Manuel Blanco-Alvarez

    2015-01-01

    Full Text Available Prophylactic subacute administration of zinc decreases lipoperoxidation and cell death following a transient cerebral hypoxia-ischemia, thus suggesting neuroprotective and preconditioning effects. Chemokines and growth factors are also involved in the neuroprotective effect in hypoxia-ischemia. We explored whether zinc prevents the cerebral cortex-hippocampus injury through regulation of CCL2, CCR2, FGF2, and IGF-1 expression following a 10 min of common carotid artery occlusion (CCAO. Male rats were grouped as follows: (1 Zn96h, rats injected with ZnCl2 (one dose every 24 h during four days; (2 Zn96h + CCAO, rats treated with ZnCl2 before CCAO; (3 CCAO, rats with CCAO only; (4 Sham group, rats with mock CCAO; and (5 untreated rats. The cerebral cortex-hippocampus was dissected at different times before and after CCAO. CCL2/CCR2, FGF2, and IGF-1 expression was assessed by RT-PCR and ELISA. Learning in Morris Water Maze was achieved by daily training during 5 days. Long-term memory was evaluated on day 7 after learning. Subacute administration of zinc increased expression of CCL2, CCR2, FGF2, and IGF-1 in the early and late phases of postreperfusion and prevented the CCAO-induced memory loss in the rat. These results might be explained by the induction of neural plasticity because of the expression of CCL2 and growth factors.

  9. Prophylactic Subacute Administration of Zinc Increases CCL2, CCR2, FGF2, and IGF-1 Expression and Prevents the Long-Term Memory Loss in a Rat Model of Cerebral Hypoxia-Ischemia.

    Science.gov (United States)

    Blanco-Alvarez, Victor Manuel; Soto-Rodriguez, Guadalupe; Gonzalez-Barrios, Juan Antonio; Martinez-Fong, Daniel; Brambila, Eduardo; Torres-Soto, Maricela; Aguilar-Peralta, Ana Karina; Gonzalez-Vazquez, Alejandro; Tomás-Sanchez, Constantino; Limón, I Daniel; Eguibar, Jose R; Ugarte, Araceli; Hernandez-Castillo, Jeanett; Leon-Chavez, Bertha Alicia

    2015-01-01

    Prophylactic subacute administration of zinc decreases lipoperoxidation and cell death following a transient cerebral hypoxia-ischemia, thus suggesting neuroprotective and preconditioning effects. Chemokines and growth factors are also involved in the neuroprotective effect in hypoxia-ischemia. We explored whether zinc prevents the cerebral cortex-hippocampus injury through regulation of CCL2, CCR2, FGF2, and IGF-1 expression following a 10 min of common carotid artery occlusion (CCAO). Male rats were grouped as follows: (1) Zn96h, rats injected with ZnCl2 (one dose every 24 h during four days); (2) Zn96h + CCAO, rats treated with ZnCl2 before CCAO; (3) CCAO, rats with CCAO only; (4) Sham group, rats with mock CCAO; and (5) untreated rats. The cerebral cortex-hippocampus was dissected at different times before and after CCAO. CCL2/CCR2, FGF2, and IGF-1 expression was assessed by RT-PCR and ELISA. Learning in Morris Water Maze was achieved by daily training during 5 days. Long-term memory was evaluated on day 7 after learning. Subacute administration of zinc increased expression of CCL2, CCR2, FGF2, and IGF-1 in the early and late phases of postreperfusion and prevented the CCAO-induced memory loss in the rat. These results might be explained by the induction of neural plasticity because of the expression of CCL2 and growth factors.

  10. Genetic polymorphism rs3760396 of the chemokine (C-C motif) ligand 2 gene (CCL2) associated with the susceptibility of lung cancer in a pathological subtype-specific manner in Han-ancestry Chinese: a case control study

    International Nuclear Information System (INIS)

    Li, Xu; Lin, Fangcai; Zhou, Hong

    2016-01-01

    Chemokines are well known inflammatory factors critical for tumor development in diverse tissues, including lung cancer. Chemokine (C-C motif) Ligand 2 (CCL2) was one of such chemokines important for both primary tumor development and metastasis of various cancers. Polymorphism at rs3760396 of CCL2 genes is associated with the prognosis of non-small cell lung cancer (NSCLC). The goal of our study was to examine the relationship of genetic polymorphisms rs3760396 with the susceptibility of lung cancer and its pathological subtypes in Han-ancestry Chinese population. rs3760396 G/C polymorphism of CCL2 was genotyped using PCR in 394 patients with lung cancer and 545 cancer-free controls from the same Northeast region of China. After controlling for gender, age and smoking status, no significant association was observed between rs3760396 polymorphism and overall lung cancer. However, minor allele G of rs3760396 polymorphism was significantly associated with increased risk of adenosquamous lung carcinoma with either allelic genetic model (OR = 5.29, P < 0.001), or dominant genetic model (OR = 9.88, P < 0.001), or genotypic model (GC genotype vs. CC genotype, OR = 10.73, P < 0.001). Although rs3760396 polymorphism was not significantly associated with increased risk of adenocarcinoma subtype, it was nominally associated with the pooled outcome of either adenocarcinoma or adenosquamous carcinoma under allelic genetic model (OR = 1.54, P = 0.023) or dominant genetic model (OR = 1.57, P = 0.031). Our study suggested rs3760396 polymorphism of CCL2 is associated not only with prognosis of NSCLC, but also with risk of lung cancer in a subtype-specific manner. Our results further supported previous evidence of the important role of CCL2 in lung cancer development

  11. Ab Initio Theoretical Studies on the Kinetics of Hydrogen Abstraction Type Reactions of Hydroxyl Radicals with CH3CCl2F and CH3CClF2

    Science.gov (United States)

    Saheb, Vahid; Maleki, Samira

    2018-03-01

    The hydrogen abstraction reactions from CH3Cl2F (R-141b) and CH3CClF2 (R-142b) by OH radicals are studied theoretically by semi-classical transition state theory. The stationary points for the reactions are located by using KMLYP density functional method along with 6-311++G(2 d,2 p) basis set and MP2 method along with 6-311+G( d, p) basis set. Single-point energy calculations are performed by the CBS-Q and G4 combination methods on the geometries optimized at the KMLYP/6-311++G(2 d,2 p) level of theory. Vibrational anharmonicity coefficients, x ij , which are needed for semi-classical transition state theory calculations, are computed at the KMLYP/6-311++G(2 d,2 p) and MP2/6-311+G( d, p) levels of theory. The computed barrier heights are slightly sensitive to the quantum-chemical method. Thermal rate coefficients are computed over the temperature range from 200 to 2000 K and they are shown to be in accordance with available experimental data. On the basis of the computed rate coefficients, the tropospheric lifetime of the CH3CCl2F and CH3CClF2 are estimated to be about 6.5 and 12.0 years, respectively.

  12. Voluntary exercise blocks Western diet-induced gene expression of the chemokines CXCL10 and CCL2 in the prefrontal cortex.

    Science.gov (United States)

    Carlin, Jesse L; Grissom, Nicola; Ying, Zhe; Gomez-Pinilla, Fernando; Reyes, Teresa M

    2016-11-01

    Obesity increases inflammation, both peripherally and centrally, and exercise can ameliorate some of the negative health outcomes associated with obesity. Within the brain, the effect of obesity on inflammation has been well characterized in the hypothalamus and hippocampus, but has been relatively understudied in other brain regions. The current study was designed to address two primary questions; (1) whether western diet (high fat/high sucrose) consumption would increase markers of inflammation in the prefrontal cortex and (2) whether concurrent voluntary wheel running would ameliorate any inflammation. Adult male mice were exposed to a western diet or a control diet for 8weeks. Concurrently, half the animals were given running wheels in their home cages, while half did not have access to wheels. At the conclusion of the study, prefrontal cortex was removed and expression of 18 proinflammatory genes was assayed. Expression of a number of proinflammatory molecules was upregulated by consumption of the western diet. For two chemokines, chemokine (C-C motif) ligand 2 (CCL2) and C-X-C motif chemokine 10 (CXCL10), voluntary exercise blocked the increase in the expression of these genes. Cluster analysis confirmed that the majority of the tested genes were upregulated by western diet, and identified another small cluster of genes that were downregulated by either diet or exercise. These data identify a proinflammatory phenotype within the prefrontal cortex of mice fed a western diet, and indicate that chemokine induction can be blocked by voluntary exercise. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Non-myeloid Cells are Major Contributors to Innate Immune Responses via Production of Monocyte Chemoattractant Protein- 1(MCP-1/CCL2

    Directory of Open Access Journals (Sweden)

    Teizo eYoshimura

    2014-01-01

    Full Text Available Monocyte chemoattractant protein-1 (MCP-1/CCL2 is a chemokine regulating the recruitment of monocytes into sites of inflammation and cancer. MCP-1 can be produced by a variety of cell types, such as macrophages, neutrophils, fibroblasts, endothelial cells and epithelial cells. Notably, macrophages produce high levels of MCP-1 in response to proinflammatory stimuli in vitro, leading to the hypothesis that macrophages are the major source of MCP-1 during inflammatory responses in vivo. In stark contrast to the hypothesis, however, there was no significant reduction in MCP-1 protein or the number of infiltrating macrophages in the peritoneal inflammatory exudates of myeloid cell-specific MCP-1-deficient mice in response to i.p injection of thioglycollate or zymosan A. Furthermore, injection of LPS into skin air pouch also had no effect on local MCP-1 production in myeloid-specific MCP-1-deficient mice. Finally, myeloid-specific MCP-1-deficiency did not reduce MCP-1 mRNA expression or macrophage infiltration in LPS-induced lung injury. These results indicate that non-myeloid cells, in response to a variety of stimulants, play a previously unappreciated role in innate immune responses as the primary source of MCP-1.

  14. UV and infrared absorption spectra, atmospheric lifetimes, and ozone depletion and global warming potentials for CCl2FCCl2F (CFC-112, CCl3CClF2 (CFC-112a, CCl3CF3 (CFC-113a, and CCl2FCF3 (CFC-114a

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    M. E. Davis

    2016-07-01

    Full Text Available The potential impact of CCl2FCF3 (CFC-114a and the recently observed CCl2FCCl2F (CFC-112, CCl3CClF2 (CFC-112a, and CCl3CF3 (CFC-113a chlorofluorocarbons (CFCs on stratospheric ozone and climate is presently not well characterized. In this study, the UV absorption spectra of these CFCs were measured between 192.5 and 235 nm over the temperature range 207–323 K. Precise parameterizations of the UV absorption spectra are presented. A 2-D atmospheric model was used to evaluate the CFC atmospheric loss processes, lifetimes, ozone depletion potentials (ODPs, and the associated uncertainty ranges in these metrics due to the kinetic and photochemical uncertainty. The CFCs are primarily removed in the stratosphere by short-wavelength UV photolysis with calculated global annually averaged steady-state lifetimes (years of 63.6 (61.9–64.7, 51.5 (50.0–52.6, 55.4 (54.3–56.3, and 105.3 (102.9–107.4 for CFC-112, CFC-112a, CFC-113a, and CFC-114a, respectively. The range of lifetimes given in parentheses is due to the 2σ uncertainty in the UV absorption spectra and O(1D rate coefficients included in the model calculations. The 2-D model was also used to calculate the CFC ozone depletion potentials (ODPs with values of 0.98, 0.86, 0.73, and 0.72 obtained for CFC-112, CFC-112a, CFC-113a, and CFC-114a, respectively. Using the infrared absorption spectra and lifetimes determined in this work, the CFC global warming potentials (GWPs were estimated to be 4260 (CFC-112, 3330 (CFC-112a, 3650 (CFC-113a, and 6510 (CFC-114a for the 100-year time horizon.

  15. Benzopyrene promotes lung cancer A549 cell migration and invasion through up-regulating cytokine IL8 and chemokines CCL2 and CCL3 expression.

    Science.gov (United States)

    Zhang, Jin; Chang, Li; Jin, Hanyu; Xia, Yaoxiong; Wang, Li; He, Wenjie; Li, Wenhui; Chen, Hong

    2016-08-01

    Tobacco-sourced carcinogen including benzopyrene (B[a]P) in lung cancer metastasis has not been fully reported. In this study, lung carcinoma A549 cell line was used to investigate the potential roles of tobacco-sourced B[a]P on cell metastasis and invasion and to assess its underlying mechanism. Effects of tobacco-sourced carcinogen on A549 cell proliferation, metastasis, and invasion were analyzed using MTT assay, Transwell assay, and scratch method, respectively. The effects of tobacco-sourced carcinogen on cytokines and chemokines secretion were detected using enzyme-linked immunosorbent assay. Moreover, correlation between inflammatory factor expression and cancer cell migration and invasion was assessed using siRNA-mediated gene silencing. Data showed that both B[a]P and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone either at high or low dose performed no significant difference on A549 cell proliferation with time increasing. 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone performed no significant difference on A549 cell migration and invasion while B[a]P significantly increased A549 cell migration and invasion compared to the control group (P A549 cells were significantly decreased compared to the control, respectively (P < 0.05), while silenced IL-8 drastically decreased the migrated and invasive cells compared to the control (P < 0.01). Taken together, this study illustrated that there may be significant correlation between smoking and lung cancer metastasis. B[a]P maybe an excellent contributor for lung cancer metastasis through up-regulating IL-8, CCL-2, and CCL-3 expression. © 2016 by the Society for Experimental Biology and Medicine.

  16. Genetic polymorphisms in the bovine toll-like receptor 4 (TLR4) and monocyte chemo attractant protein-1(CCL2) genes: SNPs distribution analysis in Bos indicus Sahiwal cattle breed.

    Science.gov (United States)

    Behl, Jyotsna Dhingra; Sharma, Anurodh; Kataria, R S; Verma, N K; Kimothi, Shiv Prasad; Bhatia, Avnish Kumar; Sodhi, Monika; Behl, Rahul; Joshi, B K

    2014-01-01

    Toll-like receptor 4 gene (TLR4) that recognizes the Gram negative bacterial ligand LPS was sequenced in the Bos indicus Sahiwal cattle breed. Ninety four single nucleotide polymorphisms (SNPs) were detected within 10.8 kb gene region. Seventeen of the SNPs were in the coding regions and the one at position 9589(A > G) in exon3 resulted in an amino acid change from Valine to Isoleucine. These SNPs led to generation of 27 TLR4 gene haplotypes. All the Sahiwal animals studied presently showed the occurrence of the genotype CC at gene position 9662, which codes for the amino acid threonine at position 674 of the TLR4 protein, and which had been reported to be associated with lower somatic cell score and, therefore, a lower susceptibility to mastitis, in Taurus cattle. This nucleotide configuration of the Toll-like receptor 4 gene of the Bos indicus Sahiwal cattle breed could possibly indicate toward a lower susceptibility to mastitis in the Sahiwal animals. Monocyte chemo-attractant protein-1 (CCL2) gene encoding for small inducible cytokine A2 that belongs to the CC chemokine family was also sequence characterized in these Sahiwal animals. The CCL2 gene was observed to have 12 polymorphic sites in 3.3 kb region of which one SNP at position 2500 (A > G) in exon 3 resulted in amino acid change from Valine to Isoleucine at position 46 of the mature CCL2 peptide. Seventeen haplotypes of the CCL2 gene were predicted corresponding to 12 genotypes detected.

  17. Hepatitis C Virus-Induced Changes in MicroRNA 107 (miRNA-107) and miRNA-449a Modulate CCL2 by Targeting the Interleukin-6 Receptor Complex in Hepatitis

    Science.gov (United States)

    Sarma, Nayan J.; Tiriveedhi, Venkataswarup; Crippin, Jeffrey S.; Chapman, William C.

    2014-01-01

    ABSTRACT Hepatitis C virus (HCV)-mediated liver diseases are one of the major health issues in the United States and worldwide. HCV infection has been reported to modulate microRNAs (miRNAs) that control various cell surface receptors and gene-regulatory complexes involved in hepatic inflammation and liver diseases. We report here that specific downregulation of miRNA-107 and miRNA-449a following HCV infection in patients with HCV-mediated liver diseases modulates expression of CCL2, an inflammatory chemokine upregulated in patients with chronic liver diseases, by targeting components of the interleukin-6 receptor (IL-6R) complex. Computational analysis for DNA-bound transcription factors in the CCL2 promoter identified adjacent binding sites for CCAAT/CEBPα, spleen focus-forming virus, proviral integration oncogene (SPI1/PU.1), and STAT3. We demonstrate that CEBPα, PU.1, and STAT3 interacted with each other physically to cooperatively bind to the promoter and activate CCL2 expression. Analysis of IL-6R and JAK1 expression in HCV patients by quantitative PCR showed significant upregulation when there was impaired miRNA-107 and miRNA-449a expression, along with upregulation of PU.1 and STAT3, but not CEBPα. miRNA-449a and miRNA-107 target expression of IL-6R and JAK1, respectively, in vitro and also inhibit IL-6 signaling and impair STAT3 activation in human hepatocytes. Taken together, our results demonstrate a novel gene-regulatory mechanism in which HCV-induced changes in miRNAs (miRNA-449a and miRNA-107) regulate CCL2 expression by activation of the IL-6-mediated signaling cascade, which we propose will result in HCV-mediated induction of inflammatory responses and fibrosis. IMPORTANCE Hepatitis C virus (HCV)-induced hepatitis is a major health concern worldwide. HCV infection results in modulation of noncoding microRNAs affecting major cellular pathways, including inflammatory responses. In this study, we have identified a microRNA-regulated pathway for the

  18. Distinct Upstream Role of Type I IFN Signaling in Hematopoietic Stem Cell-Derived and Epithelial Resident Cells for Concerted Recruitment of Ly-6Chi Monocytes and NK Cells via CCL2-CCL3 Cascade.

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    Erdenebileg Uyangaa

    Full Text Available Type I interferon (IFN-I-dependent orchestrated mobilization of innate cells in inflamed tissues is believed to play a critical role in controlling replication and CNS-invasion of herpes simplex virus (HSV. However, the crucial regulators and cell populations that are affected by IFN-I to establish the early environment of innate cells in HSV-infected mucosal tissues are largely unknown. Here, we found that IFN-I signaling promoted the differentiation of CCL2-producing Ly-6Chi monocytes and IFN-γ/granzyme B-producing NK cells, whereas deficiency of IFN-I signaling induced Ly-6Clo monocytes producing CXCL1 and CXCL2. More interestingly, recruitment of Ly-6Chi monocytes preceded that of NK cells with the levels peaked at 24 h post-infection in IFN-I-dependent manner, which was kinetically associated with the CCL2-CCL3 cascade response. Early Ly-6Chi monocyte recruitment was governed by CCL2 produced from hematopoietic stem cell (HSC-derived leukocytes, whereas NK cell recruitment predominantly depended on CC chemokines produced by resident epithelial cells. Also, IFN-I signaling in HSC-derived leukocytes appeared to suppress Ly-6Ghi neutrophil recruitment to ameliorate immunopathology. Finally, tissue resident CD11bhiF4/80hi macrophages and CD11chiEpCAM+ dendritic cells appeared to produce initial CCL2 for migration-based self-amplification of early infiltrated Ly-6Chi monocytes upon stimulation by IFN-I produced from infected epithelial cells. Ultimately, these results decipher a detailed IFN-I-dependent pathway that establishes orchestrated mobilization of Ly-6Chi monocytes and NK cells through CCL2-CCL3 cascade response of HSC-derived leukocytes and epithelium-resident cells. Therefore, this cascade response of resident-to-hematopoietic-to-resident cells that drives cytokine-to-chemokine-to-cytokine production to recruit orchestrated innate cells is critical for attenuation of HSV replication in inflamed tissues.

  19. Secretome profiling of cytokines and growth factors reveals that neuro-glial differentiation is associated with the down-regulation of Chemokine Ligand 2 (MCP-1/CCL2) in amniotic fluid derived-mesenchymal progenitor cells.

    Science.gov (United States)

    Miceli, Marco; Dell'Aversana, Carmela; Russo, Rosita; Rega, Camilla; Cupelli, Lorenzo; Ruvo, Menotti; Altucci, Lucia; Chambery, Angela

    2016-02-01

    Secreted cytokines and growth factors play a key role in the modulation of stem cell proliferation, differentiation and survival. To investigate the interplay between the changes in their expression levels, we used the newly characterized human amniotic fluid derived-mesenchymal progenitor MePR-2B cell line differentiated to a neuro-glial phenotype and exploited the very high sensitivity and versatility of magnetic beads-based immunoassays. We found that a sub-set of proteins, including the cytokines IL-6, TNFα, IL-15, IFNγ, IL-8, IL-1ra, MCP-1/CCL2, RANTES and the growth factor PDGFbb, underwent a significant down-regulation following neuro-glial differentiation, whereas the expression levels of IL-12 p70, IL-5, IL-7, bFGF, VEGF and G-CSF were increased. The role of MCP-1/CCL2, previously identified as a regulator of neural progenitor stem cell differentiation, has been further investigated at transcriptional level, revealing that both the chemokine and its receptor are co-expressed in MePR-2B cells and that are regulated upon differentiation, suggesting the presence of an autocrine and paracrine loop in differentiating cells. Moreover, we demonstrated that exogenous CCL2 is capable to affect neuro-glial differentiation in MePR-2B cells, thus providing novel evidences for the potential involvement of chemokine-mediated signaling in progenitor/stem cells differentiation processes and fate specification. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Porphyromonas gingivalis-induced production of reactive oxygen species, tumor necrosis factor-α, interleukin-6, CXCL8 and CCL2 by neutrophils from localized aggressive periodontitis and healthy donors: modulating actions of red blood cells and resolvin E1.

    Science.gov (United States)

    Damgaard, C; Kantarci, A; Holmstrup, P; Hasturk, H; Nielsen, C H; Van Dyke, T E

    2017-04-01

    Porphyromonas gingivalis is regarded as a significant contributor in the pathogenesis of periodontitis and certain systemic diseases, including atherosclerosis. P. gingivalis occasionally translocates from periodontal pockets into the circulation, where it adheres to red blood cells (RBCs). This may protect the bacterium from contact with circulating phagocytes without affecting its viability. In this in vitro study, we investigated whether human peripheral blood neutrophils from 10 subjects with localized aggressive periodontitis (LAgP) and 10 healthy controls release the proinflammatory cytokines interleukin (IL)-6, tumor necrosis factor α (TNF-α), the chemokine (C-X-C motif) ligand 8 (CXCL8; also known as IL-8) and chemokine (C-C motif) ligand 2 (CCL2; also known as monocyte chemotactic protein-1) and intracellular reactive oxygen species (ROS) in response to challenge with P. gingivalis. In addition, the impact of RBC interaction with P. gingivalis was investigated. The actions of resolvin E1 (RvE1), a known regulator of P. gingivalis induced neutrophil responses, on the cytokine and ROS responses elicited by P. gingivalis in cultures of neutrophils were investigated. Upon stimulation with P. gingivalis, neutrophils from subjects with LAgP and healthy controls released similar quantities of IL-6, TNF-α, CXCL8, CCL2 and intracellular ROS. The presence of RBCs amplified the release of IL-6, TNF-α and CCL2 statistically significant in both groups, but reduced the generation of ROS in the group of healthy controls, and showed a similar tendency in the group of subjects with LAgP. RvE1 had no impact on the production of intracellular ROS, TNF-α, IL-6, CXCL8 and CCL2 by neutrophils from either group, but tended to reduce the generation of ROS in subjects with LAgP in the absence of RBCs. Our data support that binding to RBCs protects P. gingivalis from ROS and concomitantly enhances neutrophil release of proinflammatory cytokines providing a selective

  1. Mechanisms of HIV entry into the CNS: increased sensitivity of HIV infected CD14+CD16+ monocytes to CCL2 and key roles of CCR2, JAM-A, and ALCAM in diapedesis.

    Directory of Open Access Journals (Sweden)

    Dionna W Williams

    Full Text Available As HIV infected individuals live longer, the prevalence of HIV associated neurocognitive disorders is increasing, despite successful antiretroviral therapy. CD14(+CD16(+ monocytes are critical to the neuropathogenesis of HIV as they promote viral seeding of the brain and establish neuroinflammation. The mechanisms by which HIV infected and uninfected monocytes cross the blood brain barrier and enter the central nervous system are not fully understood. We determined that HIV infection of CD14(+CD16(+ monocytes resulted in their highly increased transmigration across the blood brain barrier in response to CCL2 as compared to uninfected cells, which did not occur in the absence of the chemokine. This exuberant transmigration of HIV infected monocytes was due, at least in part, to increased CCR2 and significantly heightened sensitivity to CCL2. The entry of HIV infected and uninfected CD14(+CD16(+ monocytes into the brain was facilitated by significantly increased surface JAM-A, ALCAM, CD99, and PECAM-1, as compared to CD14(+ cells that are CD16 negative. Upon HIV infection, there was an additional increase in surface JAM-A and ALCAM on CD14(+CD16(+ monocytes isolated from some individuals. Antibodies to ALCAM and JAM-A inhibited the transmigration of both HIV infected and uninfected CD14(+CD16(+ monocytes across the BBB, demonstrating their importance in facilitating monocyte transmigration and entry into the brain parenchyma. Targeting CCR2, JAM-A, and ALCAM present on CD14(+CD16(+ monocytes that preferentially infiltrate the CNS represents a therapeutic strategy to reduce viral seeding of the brain as well as the ongoing neuroinflammation that occurs during HIV pathogenesis.

  2. Effects of Methylmercury Contained in a Diet Mimicking the Wayana Amerindians Contamination through Fish Consumption: Mercury Accumulation, Metallothionein Induction, Gene Expression Variations, and Role of the Chemokine CCL2

    Directory of Open Access Journals (Sweden)

    Daniel Brèthes

    2012-06-01

    Full Text Available Methylmercury (MeHg is a potent neurotoxin, and human beings are mainly exposed to this pollutant through fish consumption. We addressed the question of whether a diet mimicking the fish consumption of Wayanas Amerindians from French Guiana could result in observable adverse effects in mice. Wayanas adult men are subjected to a mean mercurial dose of 7 g Hg/week/kg of body weight. We decided to supplement a vegetarian-based mice diet with 0.1% of lyophilized Hoplias aimara fish, which Wayanas are fond of and equivalent to the same dose as that afflicting the Wayanas Amerindians. Total mercury contents were 1.4 ± 0.2 and 5.4 ± 0.5 ng Hg/g of food pellets for the control and aimara diets, respectively. After 14 months of exposure, the body parts and tissues displaying the highest mercury concentration on a dry weight (dw basis were hair (733 ng/g and kidney (511 ng/g, followed by the liver (77 ng/g. Surprisingly, despite the fact that MeHg is a neurotoxic compound, the brain accumulated low levels of mercury (35 ng/g in the cortex. The metallothionein (MT protein concentration only increased in those tissues (kidney, muscles in which MeHg demethylation had occurred. This can be taken as a molecular sign of divalent mercurial contamination since only Hg2+ has been reported yet to induce MT accumulation in contaminated tissues. The suppression of the synthesis of the chemokine CCL2 in the corresponding knockout (KO mice resulted in important changes in gene expression patterns in the liver and brain. After three months of exposure to an aimara-containing diet, eight of 10 genes selected (Sdhb, Cytb, Cox1, Sod1, Sod2, Mt2, Mdr1a and Bax were repressed in wild-type mice liver whereas none presented a differential expression in KO Ccl2/ mice. In the wild-type mice brain, six of 12 genes

  3. Theoretical kinetics study of the reactions CHClBr + HBr ⇄ CH2ClBr + Br, CCl2Br + HBr ⇄ CHCl2Br + Br and CClBr2 + HBr ⇄ CHClBr2 + Br

    Science.gov (United States)

    Bracco, Larisa L. B.; Tucceri, María E.; Cobos, Carlos J.

    2018-03-01

    The kinetics of CHClBr + HBr ⇄ CH2ClBr + Br (1, -1), CCl2Br + HBr ⇄ CHCl2Br + Br (2, -2) and CClBr2 + HBr ⇄ CHClBr2 + Br (3, -3) reactions at 293-787 K has been studied by using the canonical transition state theory with molecular information provided by different quantum chemical methods. The obtained rate constants (in cm3 molecule-1 s-1) are k1 = 5.24 × 10-13 exp[-1.47 kcal mol-1/RT], k-1 = 2.70 × 10-11 exp[-10.21 kcal mol-1/RT], k2 = 4.18 × 10-13 exp[-2.49 kcal mol-1/RT], k-2 = 6.96 × 10-12 exp[-7.36 kcal mol-1/RT], k3 = 3.29 × 10-13 exp[-2.20 kcal mol-1/RT], and k-3 = 8.45 × 10-13 exp[-7.10 kcal mol-1/RT]. Rate constants for (2, -2) and (3, -3) are here reported for the first time.

  4. Phospholipase D from Loxosceles laeta Spider Venom Induces IL-6, IL-8, CXCL1/GRO-α, and CCL2/MCP-1 Production in Human Skin Fibroblasts and Stimulates Monocytes Migration

    Directory of Open Access Journals (Sweden)

    José M. Rojas

    2017-04-01

    Full Text Available Cutaneous loxoscelism envenomation by Loxosceles spiders is characterized by the development of a dermonecrotic lesion, strong inflammatory response, the production of pro-inflammatory mediators, and leukocyte migration to the bite site. The role of phospholipase D (PLD from Loxosceles in the recruitment and migration of monocytes to the envenomation site has not yet been described. This study reports on the expression and production profiles of cytokines and chemokines in human skin fibroblasts treated with catalytically active and inactive recombinant PLDs from Loxosceles laeta (rLlPLD and lipid inflammatory mediators ceramide 1-phosphate (C1P and lysophosphatidic acid (LPA, and the evaluation of their roles in monocyte migration. Recombinant rLlPLD1 (active and rLlPLD2 (inactive isoforms induce interleukin (IL-6, IL-8, CXCL1/GRO-α, and CCL2/monocyte chemoattractant protein-1 (MCP-1 expression and secretion in fibroblasts. Meanwhile, C1P and LPA only exhibited a minor effect on the expression and secretion of these cytokines and chemokines. Moreover, neutralization of both enzymes with anti-rLlPLD1 antibodies completely inhibited the secretion of these cytokines and chemokines. Importantly, conditioned media from fibroblasts, treated with rLlPLDs, stimulated the transmigration of THP-1 monocytes. Our data demonstrate the direct role of PLDs in chemotactic mediator synthesis for monocytes in human skin fibroblasts and indicate that inflammatory processes play an important role during loxoscelism.

  5. Phospholipase D from Loxosceles laeta Spider Venom Induces IL-6, IL-8, CXCL1/GRO-α, and CCL2/MCP-1 Production in Human Skin Fibroblasts and Stimulates Monocytes Migration.

    Science.gov (United States)

    Rojas, José M; Arán-Sekul, Tomás; Cortés, Emmanuel; Jaldín, Romina; Ordenes, Kely; Orrego, Patricio R; González, Jorge; Araya, Jorge E; Catalán, Alejandro

    2017-04-05

    Cutaneous loxoscelism envenomation by Loxosceles spiders is characterized by the development of a dermonecrotic lesion, strong inflammatory response, the production of pro-inflammatory mediators, and leukocyte migration to the bite site. The role of phospholipase D (PLD) from Loxosceles in the recruitment and migration of monocytes to the envenomation site has not yet been described. This study reports on the expression and production profiles of cytokines and chemokines in human skin fibroblasts treated with catalytically active and inactive recombinant PLDs from Loxosceles laeta (rLlPLD) and lipid inflammatory mediators ceramide 1-phosphate (C1P) and lysophosphatidic acid (LPA), and the evaluation of their roles in monocyte migration. Recombinant rLlPLD1 (active) and rLlPLD2 (inactive) isoforms induce interleukin (IL)-6, IL-8, CXCL1/GRO-α, and CCL2/monocyte chemoattractant protein-1 (MCP-1) expression and secretion in fibroblasts. Meanwhile, C1P and LPA only exhibited a minor effect on the expression and secretion of these cytokines and chemokines. Moreover, neutralization of both enzymes with anti-rLlPLD1 antibodies completely inhibited the secretion of these cytokines and chemokines. Importantly, conditioned media from fibroblasts, treated with rLlPLDs, stimulated the transmigration of THP-1 monocytes. Our data demonstrate the direct role of PLDs in chemotactic mediator synthesis for monocytes in human skin fibroblasts and indicate that inflammatory processes play an important role during loxoscelism.

  6. Resveratrol protects cortical neurons against microglia-mediated neuroinflammation.

    Science.gov (United States)

    Zhang, Feng; Wang, Hui; Wu, Qin; Lu, Yuanfu; Nie, Jing; Xie, Xiaolong; Shi, Jingshan

    2013-03-01

    Neuroinflammation is closely associated with the pathogenesis of neurological disorders. The hallmark of neuroinflammation is considered to be microglial activation. Therefore, inhibition of microglial activation might hold a promising therapy for neurological disorders. Resveratrol, a natural non-flavonoid polyphenol found in grapes and red wine, has been recognized as a bioactive agent with potential benefit for health. Several lines of evidence show that resveratrol could exert neuroprotection against ischemia, seizure, and neurodegenerative diseases. However, the mechanisms underlying its beneficial neuroprotective effects are poorly defined. Here, by using rat primary cortical neuron-glia cultures, results showed that resveratrol attenuated lipopolysaccharide (LPS)-induced cortical neurotoxicity. Further studies revealed that microglia were responsible for resveratrol-mediated neuroprotection. Resveratrol significantly inhibited LPS-induced microglial activation and subsequent production of multiple pro-inflammatory and cytotoxic factors such as tumor necrosis factor-α, nitric oxide, and interleukin-1β. Collectively, resveratrol produced neuroprotection against microglia-induced neurotoxicity. Thus, resveratrol might represent a potential benefit for the treatment of inflammation-related neurological disorders. Copyright © 2012 John Wiley & Sons, Ltd.

  7. Emerging roles of protein kinases in microglia-mediated neuroinflammation.

    Science.gov (United States)

    Lee, Sun-Hwa; Suk, Kyoungho

    2017-12-15

    Neuroinflammation is mediated by resident central nervous system glia, neurons, peripherally derived immune cells, blood-brain barrier, and inflammatory mediators secreted from these cells. Neuroinflammation has been implicated in stroke and neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, and amyotrophic lateral sclerosis. Protein kinases have been one of the most exploited therapeutic targets in the current pharmacological research, especially in studies on cancer and inflammation. To date, 32 small-molecule protein kinase inhibitors have been approved by the United States Food and Drug Administration for the treatment of cancer and inflammation. However, there is no drug effectively targeting neuroinflammation and/or neurodegenerative diseases. Recent studies have advanced several protein kinases as important drug targets in neuroinflammation and/or neurodegenerative diseases. Here, we review emerging protein kinases potentially involved in neuroinflammation and subsequent neurodegenerative diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Validation of ACE-FTS v2.2 measurements of HCl, HF, CCl3F and CCl2F2 using space-, balloon- and ground-based instrument observations

    Directory of Open Access Journals (Sweden)

    C. Servais

    2008-10-01

    Full Text Available Hydrogen chloride (HCl and hydrogen fluoride (HF are respectively the main chlorine and fluorine reservoirs in the Earth's stratosphere. Their buildup resulted from the intensive use of man-made halogenated source gases, in particular CFC-11 (CCl3F and CFC-12 (CCl2F2, during the second half of the 20th century. It is important to continue monitoring the evolution of these source gases and reservoirs, in support of the Montreal Protocol and also indirectly of the Kyoto Protocol. The Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS is a space-based instrument that has been performing regular solar occultation measurements of over 30 atmospheric gases since early 2004. In this validation paper, the HCl, HF, CFC-11 and CFC-12 version 2.2 profile data products retrieved from ACE-FTS measurements are evaluated. Volume mixing ratio profiles have been compared to observations made from space by MLS and HALOE, and from stratospheric balloons by SPIRALE, FIRS-2 and Mark-IV. Partial columns derived from the ACE-FTS data were also compared to column measurements from ground-based Fourier transform instruments operated at 12 sites. ACE-FTS data recorded from March 2004 to August 2007 have been used for the comparisons. These data are representative of a variety of atmospheric and chemical situations, with sounded air masses extending from the winter vortex to summer sub-tropical conditions. Typically, the ACE-FTS products are available in the 10–50 km altitude range for HCl and HF, and in the 7–20 and 7–25 km ranges for CFC-11 and -12, respectively. For both reservoirs, comparison results indicate an agreement generally better than 5–10% above 20 km altitude, when accounting for the known offset affecting HALOE measurements of HCl and HF. Larger positive differences are however found for comparisons with single profiles from FIRS-2 and SPIRALE. For CFCs, the few coincident measurements available suggest that the differences

  9. Can Accelerators Accelerate Learning?

    International Nuclear Information System (INIS)

    Santos, A. C. F.; Fonseca, P.; Coelho, L. F. S.

    2009-01-01

    The 'Young Talented' education program developed by the Brazilian State Funding Agency (FAPERJ)[1] makes it possible for high-schools students from public high schools to perform activities in scientific laboratories. In the Atomic and Molecular Physics Laboratory at Federal University of Rio de Janeiro (UFRJ), the students are confronted with modern research tools like the 1.7 MV ion accelerator. Being a user-friendly machine, the accelerator is easily manageable by the students, who can perform simple hands-on activities, stimulating interest in physics, and getting the students close to modern laboratory techniques.

  10. Tetra-O-methyl nordihydroguaiaretic acid (Terameprocol inhibits the NF-κB-dependent transcription of TNF-α and MCP-1/CCL2 genes by preventing RelA from binding its cognate sites on DNA

    Directory of Open Access Journals (Sweden)

    Scholle Frank

    2010-12-01

    -α, MCP-1/CCL2, and RANTES/CCL5 although the LPS-dependent synthesis of IκB-α was not inhibited. EMSA assays did not reveal an effect of TMP on the binding of RelA to naked DNA templates in vitro. TMP did not inhibit the nuclear translocation of NF-κB RelA nor the phosphorylation of IκB-α. Conclusion TMP acts indirectly as an inhibitor of NF-κB-dependent transcription by preventing RelA from binding the promoters of certain key cytokine and chemokine genes.

  11. Acceleration Mechanisms

    OpenAIRE

    Melrose, D. B.

    2009-01-01

    Glossary I. Background and context of the subject II. Stochastic acceleration III. Resonant scattering IV. Diffusive shock acceleration V. DSA at multiple shocks VI. Applications of DSA VII. Acceleration by parallel electric fields VIII. Other acceleration mechanisms IX. Future directions X. Appendix: Quasilinear equations XI. Bibliography

  12. Laser accelerators

    International Nuclear Information System (INIS)

    Willis, W.J.

    1977-01-01

    A brief discussion is given on the feasibility of using lasers to accelerate particle beams. A rough theory of operation is developed, and numerical results are obtained for an example equivalent to the Fermilab Accelerator

  13. Laser accelerator

    OpenAIRE

    Vigil, Ricardo

    2014-01-01

    Approved for public release; distribution is unlimited In 1979,W. B. Colson and S. K. Ride proposed a new kind of electron accelerator using a uniform magnetic field in combination with a circularly-polarized laser field. A key concept is to couple the oscillating electric field to the electron’s motion so that acceleration is sustained. This dissertation investigates the performance of the proposed laser accelerator using modern high powered lasers and mag-netic fields that are significan...

  14. Electrostatic accelerators

    CERN Document Server

    Hinterberger, F

    2006-01-01

    The principle of electrostatic accelerators is presented. We consider Cockcroft– Walton, Van de Graaff and Tandem Van de Graaff accelerators. We resume high voltage generators such as cascade generators, Van de Graaff band generators, Pelletron generators, Laddertron generators and Dynamitron generators. The speci c features of accelerating tubes, ion optics and methods of voltage stabilization are described. We discuss the characteristic beam properties and the variety of possible beams. We sketch possible applications and the progress in the development of electrostatic accelerators.

  15. Accelerator development

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    Because the use of accelerated heavy ions would provide many opportunities for new and important studies in nuclear physics and nuclear chemistry, as well as other disciplines, both the Chemistry and Physics Divisions are supporting the development of a heavy-ion accelerator. The design of greatest current interest includes a tandem accelerator with a terminal voltage of approximately 25 MV injecting into a linear accelerator with rf superconducting resonators. This combined accelerator facility would be capable of accelerating ions of masses ranging over the entire periodic table to an energy corresponding to approximately 10 MeV/nucleon. This approach, as compared to other concepts, has the advantages of lower construction costs, lower operating power, 100 percent duty factor, and high beam quality (good energy resolution, good timing resolution, small beam size, and small beam divergence). The included sections describe the concept of the proposed heavy-ion accelerator, and the development program aiming at: (1) investigation of the individual questions concerning the superconducting accelerating resonators; (2) construction and testing of prototype accelerator systems; and (3) search for economical solutions to engineering problems. (U.S.)

  16. LIBO accelerates

    CERN Multimedia

    2002-01-01

    The prototype module of LIBO, a linear accelerator project designed for cancer therapy, has passed its first proton-beam acceleration test. In parallel a new version - LIBO-30 - is being developed, which promises to open up even more interesting avenues.

  17. Accelerating Value Creation with Accelerators

    DEFF Research Database (Denmark)

    Jonsson, Eythor Ivar

    2015-01-01

    accelerator programs. Microsoft runs accelerators in seven different countries. Accelerators have grown out of the infancy stage and are now an accepted approach to develop new ventures based on cutting-edge technology like the internet of things, mobile technology, big data and virtual reality. It is also...... and developing the best business ideas and support the due diligence process. Even universities are noticing that the learning experience of the action learning approach is an effective way to develop capabilities and change cultures. Accelerators related to what has historically been associated...... have the same purpose as businesses: To create customers....

  18. Induction accelerators

    CERN Document Server

    Takayama, Ken

    2011-01-01

    A broad class of accelerators rests on the induction principle whereby the accelerating electrical fields are generated by time-varying magnetic fluxes. Particularly suitable for the transport of bright and high-intensity beams of electrons, protons or heavy ions in any geometry (linear or circular) the research and development of induction accelerators is a thriving subfield of accelerator physics. This text is the first comprehensive account of both the fundamentals and the state of the art about the modern conceptual design and implementation of such devices. Accordingly, the first part of the book is devoted to the essential features of and key technologies used for induction accelerators at a level suitable for postgraduate students and newcomers to the field. Subsequent chapters deal with more specialized and advanced topics.

  19. Accelerating Inspire

    CERN Document Server

    AUTHOR|(CDS)2266999

    2017-01-01

    CERN has been involved in the dissemination of scientific results since its early days and has continuously updated the distribution channels. Currently, Inspire hosts catalogues of articles, authors, institutions, conferences, jobs, experiments, journals and more. Successful orientation among this amount of data requires comprehensive linking between the content. Inspire has lacked a system for linking experiments and articles together based on which accelerator they were conducted at. The purpose of this project has been to create such a system. Records for 156 accelerators were created and all 2913 experiments on Inspire were given corresponding MARC tags. Records of 18404 accelerator physics related bibliographic entries were also tagged with corresponding accelerator tags. Finally, as a part of the endeavour to broaden CERN's presence on Wikipedia, existing Wikipedia articles of accelerators were updated with short descriptions and links to Inspire. In total, 86 Wikipedia articles were updated. This repo...

  20. FMIT accelerator

    International Nuclear Information System (INIS)

    Armstrong, D.D.

    1983-01-01

    A 35-MeV 100-mA cw linear accelerator is being designed by Los Alamos for use in the Fusion Materials Irradiation Test (FMIT) Facility. Essential to this program is the design, construction, and evaluation of performance of the accelerator's injector, low-energy beam transport, and radio-frequency quadrupole sections before they are shipped to the facility site. The installation and testing of some of these sections have begun as well as the testing of the rf, noninterceptive beam diagnostics, computer control, dc power, and vacuum systems. An overview of the accelerator systems and the performance to date is given

  1. Horizontal Accelerator

    Data.gov (United States)

    Federal Laboratory Consortium — The Horizontal Accelerator (HA) Facility is a versatile research tool available for use on projects requiring simulation of the crash environment. The HA Facility is...

  2. Accelerator microanalysis

    International Nuclear Information System (INIS)

    Tuniz, C.

    1997-01-01

    Particle accelerators have been developed more than sixty years ago to investigate nuclear and atomic phenomena. A major shift toward applications of accelerators in the study of materials structure and composition in inter-disciplinary projects has been witnessed in the last two decades. The Australian Nuclear Science and Technology Organisation (ANSTO) has developed advanced research programs based on the use of particle and photon beams. Atmospheric pollution problems are investigated at the 3 MV Van de Graff accelerator using ion beam analysis techniques to detect toxic elements in aerosol particles. High temperature superconductor and semiconductor materials are characterised using the recoil of iodine and other heavy ions produced at ANTARES, the 10-MV Tandem accelerator. A heavy-ion microprobe is presently being developed at ANTARES to map elemental concentrations of specific elements with micro-size resolution. An Accelerator mass Spectrometry (AMS) system has been developed at ANSTO for the ultra-sensitive detection of Carbon-14, Iodine-129 and other long-lived radioisotopes. This AMS spectrometer is a key instrument for climate change studies and international safeguards. ANSTO is also managing the Australian Synchrotron Research program based on facilities developed at the Photon Factory (Japan) and at the Advanced Photon Source (USA). Advanced projects in biology, materials chemistry, structural condensed matter and other disciplines are being promoted by a consortium involving Australian universities and research institutions. This paper will review recent advances in the use of particle accelerators, with a particular emphasis on applications developed at ANSTO and related to problems of international concern, such as global environmental change, public health and nuclear proliferation

  3. Accelerator operations

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    Operations of the SuperHILAC, the Bevatron/Bevalac, and the 184-inch Synchrocyclotron during the period from October 1977 to September 1978 are discussed. These include ion source development, accelerator facilities, the Heavy Ion Spectrometer System, and Bevelac biomedical operations

  4. Acceleration grid

    International Nuclear Information System (INIS)

    Hemmerich, J.; Kupschus, P.; Fraenkle, H.

    1983-01-01

    The acceleration grid is used in nuclear fusion technique as an ion beam grid. It consists of perforated plates at different potentials situated behind one another in the axial movement direction of their through holes. In order to prevent interference in the perforated hole area due to thermal expansion, the perforated plates are fixed with elastic springiness (plate fields) at their edges. (DG) [de

  5. Accelerators course

    CERN Multimedia

    CERN. Geneva HR-RFA; Métral, E

    2006-01-01

    1a) Introduction and motivation 1b) History and accelerator types 2) Transverse beam dynamics 3a) Longitudinal beam dynamics 3b) Figure of merit of a synchrotron/collider 3c) Beam control 4) Main limiting factors 5) Technical challenges

  6. Accelerator operations

    International Nuclear Information System (INIS)

    Anon.

    1980-01-01

    This section is concerned with the operation of both the tandem-linac system and the Dynamitron, two accelerators that are used for entirely different research. Developmental activities associated with the tandem and the Dynamitron are also treated here, but developmental activities associated with the superconducting linac are covered separately because this work is a program of technology development in its own right

  7. Accelerator update

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    When the Accelerator Conference, combined International High Energy and US Particle versions, held in Dallas in May, was initially scheduled, progress nearby for the US Superconducting Supercollider was high on the preliminary agenda. With the SSC voted down by Congress in October 1993, this was no longer the case. However the content of the meeting, in terms of both its deep implications for ambitious new projects and the breadth of its scope, showed that the worldwide particle accelerator field is far from being moribund. A traditional feature of such accelerator conferences is the multiplicity of parallel sessions. No one person can attend all sessions, so that delegates can follow completely different paths and emerge with totally different impressions. Despite this overload, and despite the SSC cancellation, the general picture is one of encouraging progress over a wide range of major new projects throughout the world. At the same time, spinoff from, and applications of, accelerators and accelerator technology are becoming increasingly important. Centrestage is now CERN's LHC proton-proton collider, where a test string of superconducting magnets is operating over long periods at the nominal LHC field of 8.36 tesla or more. The assignment of the underground areas in the existing 27- kilometre LEP tunnel is now quasidefinitive (see page 3). For CERN's existing big machine, the LEP electron-positron collider, ongoing work concentrates on boosting performance using improved optics and bunch trains. But the main objective is the LEP2 scheme using superconducting accelerating cavities to boost the beam energy (see page 6). After some initial teething problems, production and operation of these cavities appears to have been mastered, at least under test conditions. A highlight at CERN last year was the first run with lead ions (December 1994, page 15). Handling these heavy particles with systems originally designed for protons calls for ingenuity. The SPS

  8. Accelerated treatment.

    Science.gov (United States)

    Barkley, H T

    1985-05-01

    In the first third of this century, the prevailing concept was that malignant cells had a brief period of sensitivity and radiation treatments were ideally given in overall times of 2 weeks or less. Following the Second World War, routine treatment times were extended to 5 to 8 weeks to avoid severe acute normal tissue reactions and achieve higher tumor doses. In reaction to these prolonged overall times, a series of large-fraction, shortened-overall-time clinical experiments were attempted, with disastrous normal tissue effects and poor tumor control. More recently, attempts to accelerate treatment have been accomplished by utilizing multiple fractions per day or semicontinuous irradiation. Unfortunately, the majority of these attempts have been forced by the occurrence of unacceptable normal tissue reactions to significantly reduce total dose or introduce lengthy splits in treatment. These results suggest that in our current state of knowledge accelerated schedules be reserved for use in the treatment of rapidly proliferating neoplasms or for palliation.

  9. Laser Accelerator

    Science.gov (United States)

    2014-09-01

    Photocathode emitters eject electrons from the cathode by the photoelectric effect. A drive laser source shines light energy onto a metal or...synchronized so that the electrons ejected via the photoelectric effect are properly accelerated. 15 Figure 2.4: Cross-section of a triple spoke cavity, from...2.3: Available Pulsed Magnets at PFF LANL. SP = Short Pulse. MP = Mid-Pulse, after [19] Cell No. Magnet Pulse Duration (ms) Bore (mm) 1 50 T SP 25 24

  10. Accelerating networks

    International Nuclear Information System (INIS)

    Smith, David M D; Onnela, Jukka-Pekka; Johnson, Neil F

    2007-01-01

    Evolving out-of-equilibrium networks have been under intense scrutiny recently. In many real-world settings the number of links added per new node is not constant but depends on the time at which the node is introduced in the system. This simple idea gives rise to the concept of accelerating networks, for which we review an existing definition and-after finding it somewhat constrictive-offer a new definition. The new definition provided here views network acceleration as a time dependent property of a given system as opposed to being a property of the specific algorithm applied to grow the network. The definition also covers both unweighted and weighted networks. As time-stamped network data becomes increasingly available, the proposed measures may be easily applied to such empirical datasets. As a simple case study we apply the concepts to study the evolution of three different instances of Wikipedia, namely, those in English, German, and Japanese, and find that the networks undergo different acceleration regimes in their evolution

  11. Advanced concepts for acceleration

    International Nuclear Information System (INIS)

    Keefe, D.

    1986-07-01

    Selected examples of advanced accelerator concepts are reviewed. Such plasma accelerators as plasma beat wave accelerator, plasma wake field accelerator, and plasma grating accelerator are discussed particularly as examples of concepts for accelerating relativistic electrons or positrons. Also covered are the pulsed electron-beam, pulsed laser accelerator, inverse Cherenkov accelerator, inverse free-electron laser, switched radial-line accelerators, and two-beam accelerator. Advanced concepts for ion acceleration discussed include the electron ring accelerator, excitation of waves on intense electron beams, and two-wave combinations

  12. Accelerators and the Accelerator Community

    Energy Technology Data Exchange (ETDEWEB)

    Malamud, Ernest; Sessler, Andrew

    2008-06-01

    In this paper, standing back--looking from afar--and adopting a historical perspective, the field of accelerator science is examined. How it grew, what are the forces that made it what it is, where it is now, and what it is likely to be in the future are the subjects explored. Clearly, a great deal of personal opinion is invoked in this process.

  13. Accelerator neutrinos

    International Nuclear Information System (INIS)

    Autiero, D.; Declais, Y.

    2005-01-01

    In the last years neutrino physics was shaken by many important experimental results bringing solid proofs in favor of neutrino oscillations. The goal of the present and future generation of experiments at accelerators is to complete the comprehension of neutrino mixing and of the pattern of neutrino masses, perform precise measurements of all these parameters and investigate CP violation in the neutrino sector. Most of these goals will be achieved with the study of ν μ → ν e oscillations, which are mainly ruled by the still unknown mixing angle Θ 13 . A multi-step experimental strategy has to be attempted, depending on the magnitude of Θ 13 . (authors)

  14. Ring accelerators

    International Nuclear Information System (INIS)

    Gisler, G.; Faehl, R.

    1983-01-01

    We present two-dimensional simulations in (r-z) and r-theta) cylinderical geometries of imploding-liner-driven accelerators of rings of charged particles. We address issues of azimuthal and longitudinal stability of the rings. We discuss self-trapping designs in which beam injection and extraction is aided by means of external cusp fields. Our simulations are done with the 2-1/2-D particle-in-cell plasma simulation code CLINER, which combines collisionless, electromagnetic PIC capabilities with a quasi-MHD finite element package

  15. accelerating cavity

    CERN Multimedia

    On the inside of the cavity there is a layer of niobium. Operating at 4.2 degrees above absolute zero, the niobium is superconducting and carries an accelerating field of 6 million volts per metre with negligible losses. Each cavity has a surface of 6 m2. The niobium layer is only 1.2 microns thick, ten times thinner than a hair. Such a large area had never been coated to such a high accuracy. A speck of dust could ruin the performance of the whole cavity so the work had to be done in an extremely clean environment.

  16. Microglia-mediated BAFF-BAFFR ligation promotes neuronal survival in brain ischemia injury.

    Science.gov (United States)

    Li, Kai; Yu, Wei; Cao, Rangjuan; Zhu, Zhihua; Zhao, Guoqing

    2017-11-05

    The innate immune responses of brain to vascular occlusion are primarily orchestrated by activated microglia. However, the roles of microglia in inflammatory responses to brain ischemic injuries are controversial. Here, we report a new mechanism by which microglia confer protective effects on ischemic neuronal cells. We found that under ischemic condition, the B-cell-activating factor (BAFF) was vastly upregulated in microglia and this upregulation could at least be attributed to JAK-STAT signaling pathway activated by IFN-γ and IL-10, which were spatio-temporally enriched in I/R-injured brain as well. Meanwhile, the expression of BAFFR, one member of BAFF receptors, was also upregulated on neurons after I/R injury. More importantly, recombinant BAFF treatment not only promoted neuronal survival under ischemic stresses in vitro but also attenuated infarct volume and neural deficit caused by middle cerebral artery occlusion (MCAO) in vivo. Furthermore, blocking BAFF-BAFFR ligation with TACI-Ig abrogated these therapeutic benefits. Taken together, these results indicate that the BAFF-BAFFR ligation bridged between microglia and neurons could play a critical neuroprotective role in I/R injury. Thus, augmenting BAFF-BAFFR signaling might represent a potential target for clinical stroke therapy. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  17. Environmental Enrichment Potently Prevents Microglia-Mediated Neuroinflammation by Human Amyloid β-Protein Oligomers.

    Science.gov (United States)

    Xu, Huixin; Gelyana, Eilrayna; Rajsombath, Molly; Yang, Ting; Li, Shaomin; Selkoe, Dennis

    2016-08-31

    Microglial dysfunction is increasingly recognized as a key contributor to the pathogenesis of Alzheimer's disease (AD). Environmental enrichment (EE) is well documented to enhance neuronal form and function, but almost nothing is known about whether and how it alters the brain's innate immune system. Here we found that prolonged exposure of naive wild-type mice to EE significantly altered microglial density and branching complexity in the dentate gyrus of hippocampus. In wild-type mice injected intraventricularly with soluble Aβ oligomers (oAβ) from hAPP-expressing cultured cells, EE prevented several morphological features of microglial inflammation and consistently prevented oAβ-mediated mRNA changes in multiple inflammatory genes both in vivo and in primary microglia cultured from the mice. Microdialysis in behaving mice confirmed that EE normalized increases in the extracellular levels of the key cytokines (CCL3, CCL4, TNFα) identified by the mRNA analysis. Moreover, EE prevented the changes in microglial gene expression caused by ventricular injection of oAβ extracted directly from AD cerebral cortex. We conclude that EE potently alters the form and function of microglia in a way that prevents their inflammatory response to human oAβ, suggesting that prolonged environmental enrichment could protect against AD by modulating the brain's innate immune system. Environmental enrichment (EE) is a potential therapy to delay Alzheimer's disease (AD). Microglial inflammation is associated with the progression of AD, but the influence of EE on microglial inflammation is unclear. Here we systematically applied in vivo methods to show that EE alters microglia in the dentate gyrus under physiological conditions and robustly prevents microglial inflammation induced by human Aβ oligomers, as shown by neutralized microglial inflammatory morphology, mRNA changes, and brain interstitial fluid cytokine levels. Our findings suggest that EE alters the innate immune system and could serve as a therapeutic approach to AD and provide new targets for drug discovery. Further, we propose that the therapeutic benefits of EE could extend to other neurodegenerative diseases involving microglial inflammation. Copyright © 2016 the authors 0270-6474/16/369041-16$15.00/0.

  18. Microglia-mediated neuroinflammation is an amplifier of virus-induced neuropathology.

    Science.gov (United States)

    Das Sarma, Jayasri

    2014-04-01

    Microglia, the major resident immune cells in the central nervous system (CNS) are considered as the key cellular mediators of neuroinflammatory processes. In the past few years, microglial research has become a main focus in cellular neuroimmunology and neuroinflammation. Chronic/remitting neurological disease such as multiple sclerosis (MS) has long been considered an inflammatory autoimmune disease with the infiltration of peripheral myelin-specific T cells into the CNS. With the rapid advancement in the field of microglia and astrocytic neurobiology, the term neuroinflammation progressively started to denote chronic CNS cell-specific inflammation in MS. The direct glial responses in MS are different from conventional peripheral immune responses. This review attempts to summarize current findings of neuroinflammatory responses within the CNS by direct infection of neural cells by mouse hepatitis virus (MHV) and the mechanisms by which glial cell responses ultimately contribute to the neuropathology on demyelination. Microglia can be persistently infected by MHV. Microglial activation and phagocytosis are recognized to be critically important in the pathogenesis of demyelination. Emerging evidence for the pathogenic role of microglia and the activation of inflammatory pathways in these cells in MHV infection supports the concept that microglia induced neuroinflammation is an amplifier of virus-induced neuropathology.

  19. Scutellarin Attenuates Microglia-Mediated Neuroinflammation and Promotes Astrogliosis in Cerebral Ischemia - A Therapeutic Consideration.

    Science.gov (United States)

    Wu, Chun-Yun; Fang, Ming; Karthikeyan, Aparna; Yuan, Yun; Ling, Eng-Ang

    2017-01-01

    Neuroinflammation plays an important role in different brain diseases including acute brain injuries such as cerebral ischemic stroke and chronic neurodegenerative diseases e.g. Alzheimer's disease etc. The central player in this is the activated microglia, which produce substantial amounts of proinflammatory mediators that may exacerbate the disease. Associated with microglia activation is astrogliosis characterized by hypertrophic astrocytes with increased expression of proinflammatory cytokines, neurotrophic factors, stem cell, neuronal and proliferation markers, all these are crucial for reconstruction of damaged tissue and ultimate restoration of neurological functions. Here, we review the roles of activated microglia and reactive astrocytes in brain diseases with special reference to cerebral ischemia, and the effects of scutellarin, a Chinese herbal extract on both glial cells. We first reviewed the close spatial relation between activated microglia and reactive astrocytes as it suggests that both glial cells work in concert for tissue reconstruction and repair. Secondly, we have identified scutellarin as a putative therapeutic agent as it has been found to not only suppress microglial activation thus ameliorating neuroinflammation, but also enhance astrocytic reaction. In the latter, scutellarin amplified the astrocytic reaction by upregulating the expression of neurotrophic factors among others thus indicating its neuroprotective role. Remarkably, the effects of scutellarin on reactive astrocytes were mediated by activated microglia supporting a functional "cross-talk" between the two glial types. This review highlights some of our recent findings taking into consideration of others demonstrating the beneficial effects of scutellarin on both glial cell types in cerebral ischemia as manifested by improvement of neurological functions. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  20. Linear Accelerator (LINAC)

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Linear Accelerator A linear accelerator (LINAC) customizes high energy x-rays or ... ensured? What is this equipment used for? A linear accelerator (LINAC) is the device most commonly used ...

  1. Future accelerator technology

    International Nuclear Information System (INIS)

    Sessler, A.M.

    1986-05-01

    A general discussion is presented of the acceleration of particles. Upon this foundation is built a categorization scheme into which all accelerators can be placed. Special attention is devoted to accelerators which employ a wake-field mechanism and a restricting theorem is examined. It is shown how the theorem may be circumvented. Comments are made on various acceleration schemes

  2. Piezoelectric particle accelerator

    Science.gov (United States)

    Kemp, Mark A.; Jongewaard, Erik N.; Haase, Andrew A.; Franzi, Matthew

    2017-08-29

    A particle accelerator is provided that includes a piezoelectric accelerator element, where the piezoelectric accelerator element includes a hollow cylindrical shape, and an input transducer, where the input transducer is disposed to provide an input signal to the piezoelectric accelerator element, where the input signal induces a mechanical excitation of the piezoelectric accelerator element, where the mechanical excitation is capable of generating a piezoelectric electric field proximal to an axis of the cylindrical shape, where the piezoelectric accelerator is configured to accelerate a charged particle longitudinally along the axis of the cylindrical shape according to the piezoelectric electric field.

  3. Advance of accelerator technology

    Energy Technology Data Exchange (ETDEWEB)

    Kamitubo, Hiromichi

    1987-08-01

    At first, accelerators were developed for the research on atomic nuclei, but as the research on the components of natural world advanced, they were made larger so as to reach higher energy, and developed so that diverse particles can be accelerated. The energy attainable with accelerators has increased to ten times in six years. To the advance of accelerators, the development of acceleration principle due to new idea or the development of the technology related to accelerators accompanied without exception. In particular, as accelerators became large scale, and their construction requires large amount of money, attention is paid to the technical development required for the construction of new accelerators as the extending effect which brings forth the technical innovation in the society. In this paper, the technical advance which is common to accelerators is outlined. As the components indispensable to accelerators, there are charged particle generators, accelerating electric field generators, vaccumizing facilities, control system, diagnostic system and so on. As to new accelerating principles, the materialization of collision type rings and beam cooling is worthy of special mention. The research on computer-aided accelerators and the techniques of accelerating electric field generation, vaccumizing, electromagnets, ion sources and others are reported. (Kako, I.).

  4. 2014 CERN Accelerator Schools: Plasma Wake Acceleration

    CERN Multimedia

    2014-01-01

    A specialised school on Plasma Wake Acceleration will be held at CERN, Switzerland from 23-29 November, 2014.   This course will be of interest to staff and students in accelerator laboratories, university departments and companies working in or having an interest in the field of new acceleration techniques. Following introductory lectures on plasma and laser physics, the course will cover the different components of a plasma wake accelerator and plasma beam systems. An overview of the experimental studies, diagnostic tools and state of the art wake acceleration facilities, both present and planned, will complement the theoretical part. Topical seminars and a visit of CERN will complete the programme. Further information can be found at: http://cas.web.cern.ch/cas/PlasmaWake2014/CERN-advert.html http://indico.cern.ch/event/285444/

  5. High brightness electron accelerator

    International Nuclear Information System (INIS)

    Sheffield, R.L.; Carlsten, B.E.; Young, L.M.

    1994-01-01

    A compact high brightness linear accelerator is provided for use, e.g., in a free electron laser. The accelerator has a first plurality of accelerating cavities having end walls with four coupling slots for accelerating electrons to high velocities in the absence of quadrupole fields. A second plurality of cavities receives the high velocity electrons for further acceleration, where each of the second cavities has end walls with two coupling slots for acceleration in the absence of dipole fields. The accelerator also includes a first cavity with an extended length to provide for phase matching the electron beam along the accelerating cavities. A solenoid is provided about the photocathode that emits the electrons, where the solenoid is configured to provide a substantially uniform magnetic field over the photocathode surface to minimize emittance of the electrons as the electrons enter the first cavity. 5 figs

  6. New methods of acceleration

    International Nuclear Information System (INIS)

    Ivanov, I.N.; Sarantsev, V.P.

    1976-01-01

    The most perspective methods of the collective acceleration of particles are considered, namely, acceleration of ions in direct electron beams and electron rings. Several models of particle acceleration by means of electron beams are described. Experimental data on the acceleration of differently charged ions show that the ion energy increases with the charge. Time-of-flight measurements show that during acceleration the ion bunch is located behind the beam front. The injection of electrons into an electron-ring accelerator and the electron acceleration are considered in detail. The most dangerous effects are described, which restrict the number of particles captured in the electron-ring accelerator. Several mechanisms are considered for retaining the cross-sectional dimensions of the moving ring

  7. San Francisco Accelerator Conference

    International Nuclear Information System (INIS)

    Southworth, Brian

    1991-01-01

    'Where are today's challenges in accelerator physics?' was the theme of the open session at the San Francisco meeting, the largest ever gathering of accelerator physicists and engineers

  8. Angular Accelerating White Light

    CSIR Research Space (South Africa)

    Dudley, Angela L

    2015-08-01

    Full Text Available angular acceleration during propagation which is achieved by superpositions of Bessel beams with non-canonical phase functions. They demonstrate these angular accelerating fields by modulating the phase and amplitude of a supercontinuum source with the use...

  9. Improved plasma accelerator

    Science.gov (United States)

    Cheng, D. Y.

    1971-01-01

    Converging, coaxial accelerator electrode configuration operates in vacuum as plasma gun. Plasma forms by periodic injections of high pressure gas that is ionized by electrical discharges. Deflagration mode of discharge provides acceleration, and converging contours of plasma gun provide focusing.

  10. Unified accelerator libraries

    International Nuclear Information System (INIS)

    Malitsky, Nikolay; Talman, Richard

    1997-01-01

    A 'Universal Accelerator Libraries' (UAL) environment is described. Its purpose is to facilitate program modularity and inter-program and inter-process communication among heterogeneous programs. The goal ultimately is to facilitate model-based control of accelerators

  11. MEQALAC rf accelerating structure

    International Nuclear Information System (INIS)

    Keane, J.; Brodowski, J.

    1981-01-01

    A prototype MEQALAC capable of replacing the Cockcroft Walton pre-injector at BNL is being fabricated. Ten milliamperes of H - beam supplied from a source sitting at a potential of -40 kilovolt is to be accelerated to 750 keV. This energy gain is provided by a 200 Megahertz accelerating system rather than the normal dc acceleration. Substantial size and cost reduction would be realized by such a system over conventional pre-accelerator systems

  12. Spin and Maximal Acceleration

    Directory of Open Access Journals (Sweden)

    Giorgio Papini

    2017-12-01

    Full Text Available We study the spin current tensor of a Dirac particle at accelerations close to the upper limit introduced by Caianiello. Continual interchange between particle spin and angular momentum is possible only when the acceleration is time-dependent. This represents a stringent limit on the effect that maximal acceleration may have on spin physics in astrophysical applications. We also investigate some dynamical consequences of maximal acceleration.

  13. Applications of particle accelerators

    International Nuclear Information System (INIS)

    Barbalat, O.

    1994-01-01

    Particle accelerators are now widely used in a variety of applications for scientific research, applied physics, medicine, industrial processing, while possible utilisation in power engineering is envisaged. Earlier presentations of this subject, given at previous CERN Accelerator School sessions have been updated with papers contributed to the first European Conference on Accelerators in Applied Research and Technology (ECAART) held in September 1989 in Frankfurt and to the Second European Particle Accelerator Conference in Nice in June 1990. (orig.)

  14. Superconducting accelerator technology

    International Nuclear Information System (INIS)

    Grunder, H.A.; Hartline, B.K.

    1986-01-01

    Modern and future accelerators for high energy and nuclear physics rely increasingly on superconducting components to achieve the required magnetic fields and accelerating fields. This paper presents a practical overview of the phenomenon of superconductivity, and describes the design issues and solutions associated with superconducting magnets and superconducting rf acceleration structures. Further development and application of superconducting components promises increased accelerator performance at reduced electric power cost

  15. Angular Acceleration without Torque?

    Science.gov (United States)

    Kaufman, Richard D.

    2012-01-01

    Hardly. Just as Robert Johns qualitatively describes angular acceleration by an internal force in his article "Acceleration Without Force?" here we will extend the discussion to consider angular acceleration by an internal torque. As we will see, this internal torque is due to an internal force acting at a distance from an instantaneous center.

  16. Acceleration: It's Elementary

    Science.gov (United States)

    Willis, Mariam

    2012-01-01

    Acceleration is one tool for providing high-ability students the opportunity to learn something new every day. Some people talk about acceleration as taking a student out of step. In actuality, what one is doing is putting a student in step with the right curriculum. Whole-grade acceleration, also called grade-skipping, usually happens between…

  17. The CERN Accelerator School

    CERN Multimedia

    2016-01-01

    Introduction to accelerator physics The CERN Accelerator School: Introduction to Accelerator Physics, which should have taken place in Istanbul, Turkey, later this year has now been relocated to Budapest, Hungary.  Further details regarding the new hotel and dates will be made available as soon as possible on a new Indico site at the end of May.

  18. Accelerators and Dinosaurs

    CERN Document Server

    Turner, Michael Stanley

    2003-01-01

    Using naturally occuring particles on which to research might have made accelerators become extinct. But in fact, results from astrophysics have made accelerator physics even more important. Not only are accelerators used in hospitals but they are also being used to understand nature's inner workings by searching for Higgs bosons, CP violation, neutrino mass and dark matter (2 pages)

  19. The Accelerator Reliability Forum

    CERN Document Server

    Lüdeke, Andreas; Giachino, R

    2014-01-01

    A high reliability is a very important goal for most particle accelerators. The biennial Accelerator Reliability Workshop covers topics related to the design and operation of particle accelerators with a high reliability. In order to optimize the over-all reliability of an accelerator one needs to gather information on the reliability of many different subsystems. While a biennial workshop can serve as a platform for the exchange of such information, the authors aimed to provide a further channel to allow for a more timely communication: the Particle Accelerator Reliability Forum [1]. This contribution will describe the forum and advertise it’s usage in the community.

  20. Industrial Application of Accelerators

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    At CERN, we are very familiar with large, high energy particle accelerators. However, in the world outside CERN, there are more than 35000 accelerators which are used for applications ranging from treating cancer, through making better electronics to removing harmful micro-organisms from food and water. These are responsible for around $0.5T of commerce each year. Almost all are less than 20 MeV and most use accelerator types that are somewhat different from what is at CERN. These lectures will describe some of the most common applications, some of the newer applications in development and the accelerator technology used for them. It will also show examples of where technology developed for particle physics is now being studied for these applications. Rob Edgecock is a Professor of Accelerator Science, with a particular interest in the medical applications of accelerators. He works jointly for the STFC Rutherford Appleton Laboratory and the International Institute for Accelerator Applications at the Univer...

  1. Industrial Application of Accelerators

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    At CERN, we are very familiar with large, high energy particle accelerators. However, in the world outside CERN, there are more than 35000 accelerators which are used for applications ranging from treating cancer, through making better electronics to removing harmful micro-organisms from food and water. These are responsible for around $0.5T of commerce each year. Almost all are less than 20 MeV and most use accelerator types that are somewhat different from what is at CERN. These lectures will describe some of the most common applications, some of the newer applications in development and the accelerator technology used for them. It will also show examples of where technology developed for particle physics is now being studied for these applications. Rob Edgecock is a Professor of Accelerator Science, with a particular interest in the medical applications of accelerators. He works jointly for the STFC Rutherford Appleton Laboratory and the International Institute for Accelerator Applications at the Uni...

  2. Accelerators for energy

    International Nuclear Information System (INIS)

    Inoue, Makoto

    2000-01-01

    A particle accelerator is a device to consume energy but not to produce it. Then, the titled accelerator seems to mean an accelerator for using devices related to nuclear energy. For an accelerator combined to nuclear fissionable fuel, neutron sources are D-T type, (gamma, n) reaction using electron beam type spallation type, and so forth. At viewpoints of powers of incident beam and formed neutron, a spallation type source using high energy proton is told to be effective but others have some advantages by investigation on easy operability, easy construction, combustion with target, energy and directivity of neutron, and so forth. Here were discussed on an accelerator for research on accelerator driven energy system by dividing its researching steps, and on kind, energy, beam intensity, and so forth of an accelerator suitable for it. And, space electric charge effect at beam propagation direction controlled by beam intensity of cyclotron was also commented. (G.K.)

  3. Particle-accelerator decommissioning

    International Nuclear Information System (INIS)

    Opelka, J.H.; Mundis, R.L.; Marmer, G.J.; Peterson, J.M.; Siskind, B.; Kikta, M.J.

    1979-12-01

    Generic considerations involved in decommissioning particle accelerators are examined. There are presently several hundred accelerators operating in the United States that can produce material containing nonnegligible residual radioactivity. Residual radioactivity after final shutdown is generally short-lived induced activity and is localized in hot spots around the beam line. The decommissioning options addressed are mothballing, entombment, dismantlement with interim storage, and dismantlement with disposal. The recycle of components or entire accelerators following dismantlement is a definite possibility and has occurred in the past. Accelerator components can be recycled either immediately at accelerator shutdown or following a period of storage, depending on the nature of induced activation. Considerations of cost, radioactive waste, and radiological health are presented for four prototypic accelerators. Prototypes considered range from small accelerators having minimal amounts of radioactive mmaterial to a very large accelerator having massive components containing nonnegligible amounts of induced activation. Archival information on past decommissionings is presented, and recommendations concerning regulations and accelerator design that will aid in the decommissioning of an accelerator are given

  4. Schooling in Times of Acceleration

    Science.gov (United States)

    Buddeberg, Magdalena; Hornberg, Sabine

    2017-01-01

    Modern societies are characterised by forms of acceleration, which influence social processes. Sociologist Hartmut Rosa has systematised temporal structures by focusing on three categories of social acceleration: technical acceleration, acceleration of social change, and acceleration of the pace of life. All three processes of acceleration are…

  5. Acceleration of radioactive ions

    International Nuclear Information System (INIS)

    Laxdal, R.E.

    2003-01-01

    There is an intense interest world-wide in the use of radioactive ion beams (RIBs) for experiment. In many existing or proposed facilities ions are produced or collected at source potential, ionized and re-accelerated. Within the past year three new ISOL based facilities have added dedicated post-accelerators to deliver accelerated RIBs to experiment. The paper gives an overview of RIB accelerators present and future, and explores the inherent features in the various acceleration methods with an emphasis on heavy ion linacs. The ISAC-I and ISAC-II post-accelerators are discussed as examples. Commissioning results and initial operating experience with ISAC-I will be presented

  6. 2014 Accelerators meeting, Grenoble

    International Nuclear Information System (INIS)

    Lucotte, Arnaud; Lamy, Thierry; De Conto, Jean-Marie; Fontaine, Alain; Revol, Jean-Luc; Nadolski, Laurent S.; Kazamias, Sophie; Vretenar, Maurizio; Ferrando, Philippe; Laune, Bernard; Vedrine, Pierre

    2014-10-01

    The Accelerators meeting is organised every two years by the Accelerators division of the French Society of Physics (SFP). It brings together about 50 participants during a one-day meeting. The morning sessions are devoted to scientific presentations while the afternoon is dedicated to technical visits of facilities. This document brings together the available presentations (slides): 1 - Presentation of the Laboratory of subatomic physics and cosmology - LPSC-Grenoble (Lucotte, Arnaud; Lamy, Thierry); 2 - Presentation of the Accelerators division of the French Society of Physics (Fontaine, Alain; Revol, Jean-Luc); 3 - Presentation of Grenoble's master diplomas in Accelerator physics (Nadolski, Laurent S.); 4 - Presentation of Paris' master diplomas in big instruments (Kazamias, Sophie); 5 - Particle accelerators and European Union's projects (Vretenar, Maurizio); 6 - French research infrastructures (Ferrando, Philippe); 7 - Coordination of accelerators activity in France (Laune, Bernard; Vedrine, Pierre)

  7. Accelerator reliability workshop

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, L.; Duru, Ph.; Koch, J.M.; Revol, J.L.; Van Vaerenbergh, P.; Volpe, A.M.; Clugnet, K.; Dely, A.; Goodhew, D

    2002-07-01

    About 80 experts attended this workshop, which brought together all accelerator communities: accelerator driven systems, X-ray sources, medical and industrial accelerators, spallation sources projects (American and European), nuclear physics, etc. With newly proposed accelerator applications such as nuclear waste transmutation, replacement of nuclear power plants and others. Reliability has now become a number one priority for accelerator designers. Every part of an accelerator facility from cryogenic systems to data storage via RF systems are concerned by reliability. This aspect is now taken into account in the design/budget phase, especially for projects whose goal is to reach no more than 10 interruptions per year. This document gathers the slides but not the proceedings of the workshop.

  8. Accelerator reliability workshop

    International Nuclear Information System (INIS)

    Hardy, L.; Duru, Ph.; Koch, J.M.; Revol, J.L.; Van Vaerenbergh, P.; Volpe, A.M.; Clugnet, K.; Dely, A.; Goodhew, D.

    2002-01-01

    About 80 experts attended this workshop, which brought together all accelerator communities: accelerator driven systems, X-ray sources, medical and industrial accelerators, spallation sources projects (American and European), nuclear physics, etc. With newly proposed accelerator applications such as nuclear waste transmutation, replacement of nuclear power plants and others. Reliability has now become a number one priority for accelerator designers. Every part of an accelerator facility from cryogenic systems to data storage via RF systems are concerned by reliability. This aspect is now taken into account in the design/budget phase, especially for projects whose goal is to reach no more than 10 interruptions per year. This document gathers the slides but not the proceedings of the workshop

  9. Acceleration of deuterons in the KEK accelerator

    International Nuclear Information System (INIS)

    Kobayashi, Masaaki; Mizumachi, Yoshihiko; Okumura, Shoji.

    1975-11-01

    A possibility for acceleration of deuterons in the KEK accelerator is presented with some modifications required to the present machine. Deuteron beam of an intensity as high as 350 mA was obtained in the present duoplasmatron ion source. The emittance and acceptane of the 20-MeV proton linac are calculated for deuterons. A modification in the field distribution by means of tuners is considered to save the rf power and to improve the longitudinal emittance. Acceleration in the booster and main synchrotrons as well as in the 180-GeV intersecting storage ring proposed for a KEK future project are discussed. Intensity of the obtainable neutron beam is also estimated. (auth.)

  10. Wake field accelerators

    International Nuclear Information System (INIS)

    Wilson, P.B.

    1986-02-01

    In a wake field accelerator a high current driving bunch injected into a structure or plasma produces intense induced fields, which are in turn used to accelerate a trailing charge or bunch. The basic concepts of wake field acceleration are described. Wake potentials for closed cavities and periodic structures are derived, as are wake potentials on a collinear path with a charge distribution. Cylindrically symmetric structures excited by a beam in the form of a ring are considered

  11. Miniaturization Techniques for Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, James E.

    2003-05-27

    The possibility of laser driven accelerators [1] suggests the need for new structures based on micromachining and integrated circuit technology because of the comparable scales. Thus, we are exploring fully integrated structures including sources, optics (for both light and particle) and acceleration in a common format--an accelerator-on-chip (AOC). Tests suggest a number of preferred materials and techniques but no technical or fundamental roadblocks at scales of order 1 {micro}m or larger.

  12. CERN Accelerator School

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    The CERN Accelerator School (CAS) recently held its Advanced Accelerator Physics course in Greece on the island of Rhodes. Complementing the general course in Finland last year, this course was organized together with the University of Athens and NCSR. Demokritos. Accelerator specialists from Europe, CIS, Japan and USA followed two weeks of ''state-of-theart'' lectures designed to complete their education in the field

  13. Plasma particle accelerators

    International Nuclear Information System (INIS)

    Dawson, J.M.

    1988-01-01

    The Superconducting Supercollider (SSC) will require an 87-kilometer accelerator ring to boost particles to 40 TeV. The SSC's size is due in part to the fact that its operating principle is the same one that has dominated accelerator design for 50 years: it guides particles by means of magnetic fields and propels them by strong electric fields. If one were to build an equally powerful but smaller accelerator, one would need to increase the strength of the guiding and propelling fields. Actually, however, conventional technology may not be able to provide significant increases in field strength. There are two reasons. First, the forces from magnetic fields are becoming greater than the structural forces that hold a magnetic material together; the magnets that produce these fields would themselves be torn apart. Second, the energy from electric fields is reaching the energies that bind electrons to atoms; it would tear electrons from nuclei in the accelerator's support structures. It is the electric field problem that plasma accelerators can overcome. Plasma particle accelerators are based on the principle that particles can be accelerated by the electric fields generated within a plasma. Because the plasma has already been ionized, plasma particle accelerators are not susceptible to electron dissociation. They can in theory sustain accelerating fields thousands of times stronger that conventional technologies. So far two methods for creating plasma waves for accelerators have been proposed and tested: the wakefield and the beat wave. Although promising electric fields have been produced, more research is necessary to determine whether plasma particle accelerators can compete with the existing accelerators. 7 figs

  14. The maximal acceleration group

    International Nuclear Information System (INIS)

    Brandt, H.E.

    1984-01-01

    On the basis of the maximal proper acceleration relative to the vacuum, a line element and differential geometry of eight-dimensional phase space are constructed. The maximal acceleration group is defined as the mathematical transformation group under which the eight dimensional line element is invariant. In the classical limit of vanishing Planck's constant, the maximal acceleration group and geometry reduce to those of general relativity

  15. Interacting with accelerators

    International Nuclear Information System (INIS)

    Dasgupta, S.

    1994-01-01

    Accelerators are research machines which produce energetic particle beam for use as projectiles to effect nuclear reactions. These machines along with their services and facilities may occupy very large areas. The man-machine interface of accelerators has evolved with technological changes in the computer industry and may be partitioned into three phases. The present paper traces the evolution of man-machine interface from the earliest accelerators to the present computerized systems incorporated in modern accelerators. It also discusses the advantages of incorporating expert system technology for assisting operators. (author). 8 ref

  16. Laser-driven accelerators

    International Nuclear Information System (INIS)

    Anon.

    1982-01-01

    Several devices for using laser fields have been proposed and they can be classified in three broad categories - 'far-field' accelerators (such as the principle of inverse free electron lasers), 'media' accelerators (which, for example, use the inverse Cherenkov effect or laser-controlled plasma waves), and 'near-field' accelerators (using a loaded guiding structure such as cavities or gratings). These different approaches come from the fact that a particle cannot be accelerated by the absorption of single photons (because of momentum conservation) and thus some other element has to intervene. (orig./HSI).

  17. Accelerator-based BNCT.

    Science.gov (United States)

    Kreiner, A J; Baldo, M; Bergueiro, J R; Cartelli, D; Castell, W; Thatar Vento, V; Gomez Asoia, J; Mercuri, D; Padulo, J; Suarez Sandin, J C; Erhardt, J; Kesque, J M; Valda, A A; Debray, M E; Somacal, H R; Igarzabal, M; Minsky, D M; Herrera, M S; Capoulat, M E; Gonzalez, S J; del Grosso, M F; Gagetti, L; Suarez Anzorena, M; Gun, M; Carranza, O

    2014-06-01

    The activity in accelerator development for accelerator-based BNCT (AB-BNCT) both worldwide and in Argentina is described. Projects in Russia, UK, Italy, Japan, Israel, and Argentina to develop AB-BNCT around different types of accelerators are briefly presented. In particular, the present status and recent progress of the Argentine project will be reviewed. The topics will cover: intense ion sources, accelerator tubes, transport of intense beams, beam diagnostics, the (9)Be(d,n) reaction as a possible neutron source, Beam Shaping Assemblies (BSA), a treatment room, and treatment planning in realistic cases. © 2013 Elsevier Ltd. All rights reserved.

  18. Accelerator Review Report 2014

    OpenAIRE

    Tovey, Dan; Appleby, Rob; Bartolini, Riccardo; Bruning, Oliver; Clarke, Jim; Flint, Jonathan; Kilcoyne, Susan H.; Thomason, John; Jamieson, Charlotte; The Accelerator Science and Technology Centre (ASTeC); The Cockcroft Institute (CI); The John Adams Institute for Accelerator Science (JAI)

    2014-01-01

    The panel was created to review the accelerator programme and provide information on the breadth and scope of the STFC’s current accelerator R&D portfolio. The review’s prime driver is to underpin the development of the STFC accelerator landscape and strategy. The panel’s report will go to SB for comment and development of a high-level accelerator strategy, taking into account information from parallel reviews on neutron and photon activities. The ASB will then establish a more detailed accel...

  19. Superconducting linear accelerator cryostat

    International Nuclear Information System (INIS)

    Ben-Zvi, I.; Elkonin, B.V.; Sokolowski, J.S.

    1984-01-01

    A large vertical cryostat for a superconducting linear accelerator using quarter wave resonators has been developed. The essential technical details, operational experience and performance are described. (author)

  20. Acceleration of polarized protons in circular accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Courant, E.D.; Ruth, R.D.

    1980-09-12

    The theory of depolarization in circular accelerators is presented. The spin equation is first expressed in terms of the particle orbit and then converted to the equivalent spinor equation. The spinor equation is then solved for three different situations: (1) a beam on a flat top near a resonance, (2) uniform acceleration through an isolated resonance, and (3) a model of a fast resonance jump. Finally, the depolarization coefficient, epsilon, is calculated in terms of properties of the particle orbit and the results are applied to a calculation of depolarization in the AGS.

  1. Fermi acceleration in astrophysical jets

    OpenAIRE

    Rieger, Frank M.; Bosch-Ramon, Valenti; Duffy, Peter

    2006-01-01

    We consider the acceleration of energetic particles by Fermi processes (i.e., diffusive shock acceleration, second order Fermi acceleration, and gradual shear acceleration) in relativistic astrophysical jets, with particular attention given to recent progress in the field of viscous shear acceleration. We analyze the associated acceleration timescales and the resulting particle distributions, and discuss the relevance of these processes for the acceleration of charged particles in the jets of...

  2. Asia honours accelerator physicists

    CERN Multimedia

    2010-01-01

    "Steve Meyers of Cern and Jie Wei of Beijing's Tsinghua University are the first recipients of a new prize for particle physics. The pair were honoured for their contributions to numerous particle-accelerator projects - including Cern's Large Hadron Collider - by the Asian Committee for Future Accelerators (ACFA)..." (1 paragraph)

  3. Thoughts of accelerator tubes

    International Nuclear Information System (INIS)

    Larson, J.D.

    1977-01-01

    A brief, subjective review is given of mechanisms that may be limiting electrostatic accelerator tubes to present levels of performance. Suggestions are made for attacking these limitations with the purpose of stimulating the thinking of designers and users of electrostatic accelerators

  4. Thoughts of accelerator tubes

    Energy Technology Data Exchange (ETDEWEB)

    Larson, J D

    1977-01-01

    A brief, subjective review is given of mechanisms that may be limiting electrostatic accelerator tubes to present levels of performance. Suggestions are made for attacking these limitations with the purpose of stimulating the thinking of designers and users of electrostatic accelerators.

  5. Santa Fe Accelerator Conference

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    The 10th USA National Particle Accelerator Conference was hosted this year by the Los Alamos National Laboratory in Santa Fe from 21-23 March. It was a resounding success in emphasizing the ferment of activity in the accelerator field. About 900 people registered and about 500 papers were presented in invited and contributed talks and poster sessions

  6. Accelerators for heavy ions

    International Nuclear Information System (INIS)

    Martin, J.A.

    1975-01-01

    The use of heavy ion accelerators in nuclear physics, nuclear chemistry, atomic physics, and in material sciences studies is rapidly increasing. A review is given of the present and developing scene in heavy ion accelerator concepts and technology. The area of applicability of various methods, likely avenues of future development, and the trends of future requirements are discussed. (auth)

  7. Accelerator breeder concept

    International Nuclear Information System (INIS)

    Bartholomew, G.A.; Fraser, J.S.; Garvey, P.M.

    1978-10-01

    The principal components and functions of an accelerator breeder are described. The role of the accelerator breeder as a possible long-term fissile production support facility for CANDU (Canada Deuterium Uranium) thorium advanced fuel cycles and the Canadian research and development program leading to such a facility are outlined. (author)

  8. Accelerator for nuclear transmutation

    International Nuclear Information System (INIS)

    Schapira, J.P.

    1984-01-01

    A review on nuclear transmutation of radioactive wastes using particle accelerators is given. Technical feasibility, nuclear data, costs of various projects are discussed. It appears that one high energy accelerator (1500 MeV, 300 mA proton) could probably handle the amount of actinides generated by the actual French nuclear program [fr

  9. KEK digital accelerator

    Directory of Open Access Journals (Sweden)

    T. Iwashita

    2011-07-01

    Full Text Available The High Energy Accelerator Research Organization KEK digital accelerator (KEK-DA is a renovation of the KEK 500 MeV booster proton synchrotron, which was shut down in 2006. The existing 40 MeV drift tube linac and rf cavities have been replaced by an electron cyclotron resonance (ECR ion source embedded in a 200 kV high-voltage terminal and induction acceleration cells, respectively. A DA is, in principle, capable of accelerating any species of ion in all possible charge states. The KEK-DA is characterized by specific accelerator components such as a permanent magnet X-band ECR ion source, a low-energy transport line, an electrostatic injection kicker, an extraction septum magnet operated in air, combined-function main magnets, and an induction acceleration system. The induction acceleration method, integrating modern pulse power technology and state-of-art digital control, is crucial for the rapid-cycle KEK-DA. The key issues of beam dynamics associated with low-energy injection of heavy ions are beam loss caused by electron capture and stripping as results of the interaction with residual gas molecules and the closed orbit distortion resulting from relatively high remanent fields in the bending magnets. Attractive applications of this accelerator in materials and biological sciences are discussed.

  10. Racetrack linear accelerators

    International Nuclear Information System (INIS)

    Rowe, C.H.; Wilton, M.S. de.

    1979-01-01

    An improved recirculating electron beam linear accelerator of the racetrack type is described. The system comprises a beam path of four straight legs with four Pretzel bending magnets at the end of each leg to direct the beam into the next leg of the beam path. At least one of the beam path legs includes a linear accelerator. (UK)

  11. Hamburg Accelerator Conference (2)

    International Nuclear Information System (INIS)

    Wilson, Edmund J.N.

    1992-01-01

    From 20-24 July, Hamburg welcomed the Fifteenth International Conference on High Energy Accelerators (HEACC). The HEACC Conference traditionally reviews the status of all major accelerator projects whether they are already running like clockwork, still in the construction phase, or waiting impatiently for financial approval

  12. Unified accelerator libraries

    International Nuclear Information System (INIS)

    Malitsky, N.; Talman, R.

    1997-01-01

    A open-quotes Universal Accelerator Librariesclose quotes (UAL) environment is described. Its purpose is to facilitate program modularity and inter-program and inter-process communication among heterogeneous programs. The goal ultimately is to facilitate model-based control of accelerators. copyright 1997 American Institute of Physics

  13. Accelerators, Beams And Physical Review Special Topics - Accelerators And Beams

    Energy Technology Data Exchange (ETDEWEB)

    Siemann, R.H.; /SLAC

    2011-10-24

    Accelerator science and technology have evolved as accelerators became larger and important to a broad range of science. Physical Review Special Topics - Accelerators and Beams was established to serve the accelerator community as a timely, widely circulated, international journal covering the full breadth of accelerators and beams. The history of the journal and the innovations associated with it are reviewed.

  14. The Atomki accelerator center

    Science.gov (United States)

    Vajda, I.; Fülöp, Zs.; Biri, S.

    2017-06-01

    Particle accelerators are the driving forces of nuclear physics laboratories and MTA Atomki, the Institute for Nuclear Research of the Hungarian Academy of Sciences is no exception. The Atomki Accelerator Center (AAC) incorporates several low-energy charged-particle accelerators, offering the possibility of choosing ions with various charge states, energies and beam intensities. Currently, the AAC has six main facilities: a cyclotron (K=20), two Van de Graaff accelerators (1 MV, 5 MV), an ECR ion source, an electromagnetic isotope separator and a 2 MV Tandetron installed in 2015. The accelerators, spanning a range of beam energies from 50 eV to 27 MeV, have been designed for a broad range of research projects and applications in various fields - mainly in nuclear and atomic physics, materials science, environmental research and archaeology. The structure of the laboratory with a short description of the most important topics, education and outreach activities are presented.

  15. Collinear wake field acceleration

    International Nuclear Information System (INIS)

    Bane, K.L.F.; Chen, P.; Wilson, P.B.

    1985-04-01

    In the Voss-Weiland scheme of wake field acceleration a high current, ring-shaped driving bunch is used to accelerate a low current beam following along on axis. In such a structure, the transformer ratio, i.e., the ratio of maximum voltage that can be gained by the on-axis beam and the voltage lost by the driving beam, can be large. In contrast, it has been observed that for an arrangement in which driving and driven bunches follow the same path, and where the current distribution of both bunches is gaussian, the transformer ratio is not normally greater than two. This paper explores some of the possibilities and limitations of a collinear acceleration scheme. In addition to its application to wake field acceleration in structures, this study is also of interest for the understanding of the plasma wake field accelerator. 11 refs., 4 figs

  16. 2016 Accelerators meeting

    International Nuclear Information System (INIS)

    Spiro, Michel; Revol, Jean-Luc; Biarrotte, Jean-Luc; Napoly, Olivier; Jardin, Pascal; Chautard, Frederic; Thomas, Jean Charles; Petit, Eric

    2016-09-01

    The Accelerators meeting is organised every two years by the Accelerators division of the French Society of Physics (SFP). It brings together about 50 participants during a one-day meeting. The morning sessions are devoted to scientific presentations while the afternoon is dedicated to technical visits of facilities. This document brings together the available presentations (slides): 1 - Presentation of the Ganil - Grand accelerateur national d'ions lourds/Big national heavy-ion accelerator, Caen (Jardin, Pascal); 2 - Presentation of the Accelerators division of the French Society of Physics (Revol, Jean-Luc); 3 - Forward-looking and Prospective view (Napoly, Olivier); 4 - Accelerators at the National Institute of Nuclear and particle physics, situation, Forward-looking and Prospective view (Biarrotte, Jean-Luc); 5 - GANIL-SPIRAL2, missions and goals (Thomas, Jean Charles); 6 - The SPIRAL2 project (Petit, Eric)

  17. Superconductivity and future accelerators

    International Nuclear Information System (INIS)

    Danby, G.T.; Jackson, J.W.

    1963-01-01

    For 50 years particle accelerators employing accelerating cavities and deflecting magnets have been developed at a prodigious rate. New accelerator concepts and hardware ensembles have yielded great improvements in performance and GeV/$. The great idea for collective acceleration resulting from intense auxiliary charged-particle beams or laser light may or may not be just around the corner. In its absence, superconductivity (SC) applied both to rf cavities and to magnets opened up the potential for very large accelerators without excessive energy consumption and with other economies, even with the cw operation desirable for colliding beams. HEP has aggressively pioneered this new technology: the Fermilab single ring 1 TeV accelerator - 2 TeV collider is near the testing stage. Brookhaven National Laboratory's high luminosity pp 2 ring 800 GeV CBA collider is well into construction. Other types of superconducting projects are in the planning stage with much background R and D accomplished. The next generation of hadron colliders under discussion involves perhaps a 20 TeV ring (or rings) with 40 TeV CM energy. This is a very large machine: even if the highest practical field B approx. 10T is used, the radius is 10x that of the Fermilab accelerator. An extreme effort to get maximum GeV/$ may be crucial even for serious consideration of funding

  18. Multicavity proton cyclotron accelerator

    Directory of Open Access Journals (Sweden)

    J. L. Hirshfield

    2002-08-01

    Full Text Available A mechanism for acceleration of protons is described, in which energy gain occurs near cyclotron resonance as protons drift through a sequence of rotating-mode TE_{111} cylindrical cavities in a strong nearly uniform axial magnetic field. Cavity resonance frequencies decrease in sequence from one another with a fixed frequency interval Δf between cavities, so that synchronism can be maintained between the rf fields and proton bunches injected at intervals of 1/Δf. An example is presented in which a 122 mA, 1 MeV proton beam is accelerated to 961 MeV using a cascade of eight cavities in an 8.1 T magnetic field, with the first cavity resonant at 120 MHz and with Δf=8 MHz. Average acceleration gradient exceeds 40 MV/m, average effective shunt impedance is 223 MΩ/m, but maximum surface field in the cavities does not exceed 7.2 MV/m. These features occur because protons make many orbital turns in each cavity and thus experience acceleration from each cavity field many times. Longitudinal and transverse stability appear to be intrinsic properties of the acceleration mechanism, and an example to illustrate this is presented. This acceleration concept could be developed into a proton accelerator for a high-power neutron spallation source, such as that required for transmutation of nuclear waste or driving a subcritical fission burner, provided a number of significant practical issues can be addressed.

  19. The miniature accelerator

    CERN Multimedia

    Antonella Del Rosso

    2015-01-01

    The image that most people have of CERN is of its enormous accelerators and their capacity to accelerate particles to extremely high energies. But thanks to some cutting-edge studies on beam dynamics and radiofrequency technology, along with innovative construction techniques, teams at CERN have now created the first module of a brand-new accelerator, which will be just 2 metres long. The potential uses of this miniature accelerator will include deployment in hospitals for the production of medical isotopes and the treatment of cancer. It’s a real David-and-Goliath story.   Serge Mathot, in charge of the construction of the "mini-RFQ", pictured with the first of the four modules that will make up the miniature accelerator. The miniature accelerator consists of a radiofrequency quadrupole (RFQ), a component found at the start of all proton accelerator chains around the world, from the smallest to the largest. The LHC is designed to produce very high-intensity beams ...

  20. Large electrostatic accelerators

    International Nuclear Information System (INIS)

    Jones, C.M.

    1984-01-01

    The increasing importance of energetic heavy ion beams in the study of atomic physics, nuclear physics, and materials science has partially or wholly motivated the construction of a new generation of large electrostatic accelerators designed to operate at terminal potentials of 20 MV or above. In this paper, the author briefly discusses the status of these new accelerators and also discusses several recent technological advances which may be expected to further improve their performance. The paper is divided into four parts: (1) a discussion of the motivation for the construction of large electrostatic accelerators, (2) a description and discussion of several large electrostatic accelerators which have been recently completed or are under construction, (3) a description of several recent innovations which may be expected to improve the performance of large electrostatic accelerators in the future, and (4) a description of an innovative new large electrostatic accelerator whose construction is scheduled to begin next year. Due to time and space constraints, discussion is restricted to consideration of only tandem accelerators

  1. Application of Accelerators and Storage Rings: Accelerators in Medicine

    CERN Document Server

    Amaldi, U

    2013-01-01

    This document is part of Subvolume C 'Accelerators and Colliders' of Volume 21 'Elementary Particles' of Landolt-Börnstein - Group I 'Elementary Particles, Nuclei and Atoms'. It contains the the Section '11.3 Accelerators in Medicine' of the Chapter '11 Application of Accelerators and Storage Rings' with the content: 11.3 Accelerators in Medicine 11.3.1 Accelerators and Radiopharmaceuticals 11.3.2 Accelerators and Cancer Therapy

  2. Special PS Accelerator Seminar Instabilities in accelerators

    CERN Document Server

    Wilson, Edmund J N

    1988-01-01

    This 9 week course under the auspices of PS Seminars is intended for anyone with a technical or scientific background who would like to become familiar with the principles of accelerator design. The level of the course is chosen with the intention of preparing those with no specialist knowledge of accelerator theoryfor the CERN Accelerator School in September but it will also be of interest to a much wider audience from all the technical Divisions. The first two talks (2 May at 11.00 hrs and 11 May* at 14.00 hrs) will be by way of mathematical introduction for those whose matrix algebra and solution of differential equations may need refreshing. Starting on 16 May there will be a series of seven talks on all aspects of circular machines which will cover in a simple way the principles of focussing betatron motion, dispersion chromaticity radio frequency systems and phase stability and beam instabilities. The special features of electron machines will be emphasized in preparation for LEP. All sessions will be h...

  3. RF linear accelerators

    CERN Document Server

    Wangler, Thomas P

    2008-01-01

    Thomas P. Wangler received his B.S. degree in physics from Michigan State University, and his Ph.D. degree in physics and astronomy from the University of Wisconsin. After postdoctoral appointments at the University of Wisconsin and Brookhaven National Laboratory, he joined the staff of Argonne National Laboratory in 1966, working in the fields of experimental high-energy physics and accelerator physics. He joined the Accelerator Technology Division at Los Alamos National Laboratory in 1979, where he specialized in high-current beam physics and linear accelerator design and technology. In 2007

  4. Auroral electron acceleration

    International Nuclear Information System (INIS)

    Bryant, D.A.

    1989-10-01

    Two theories of auroral electron acceleration are discussed. Part 1 examines the currently widely held view that the acceleration is an ordered process in a quasi-static electric field. It is suggested that, although there are many factors seeming to support this theory, the major qualifications and uncertainties that have been identified combine to cast serious doubt over its validity. Part 2 is devoted to a relatively new interpretation in terms of stochastic acceleration in turbulent electric fields. This second theory, which appears to account readily for most known features of the electron distribution function, is considered to provide a more promising approach to this central question in magnetospheric plasma physics. (author)

  5. The auroral electron accelerator

    International Nuclear Information System (INIS)

    Bryant, D.A.; Hall, D.S.

    1989-01-01

    A model of the auroral electron acceleration process is presented in which the electrons are accelerated resonantly by lower-hybrid waves. The essentially stochastic acceleration process is approximated for the purposes of computation by a deterministic model involving an empirically derived energy transfer function. The empirical function, which is consistent with all that is known of electron energization by lower-hybrid waves, allows many, possibly all, observed features of the electron distribution to be reproduced. It is suggested that the process occurs widely in both space and laboratory plasmas. (author)

  6. Advanced Accelerator Concepts

    Science.gov (United States)

    Siemann, Robert

    1998-04-01

    Current particle accelerators rely on conventional or superconducting radio frequency cavities to accelerate beams of protons or electrons for nuclear and particle research and for medical and materials science studies. New methods for achieving larger accelerating gradients have been proposed and are being studied. These include the use of high power lasers, laser driven plasmas, wake fields generated by intense low energy beams, and millimeter wavelength EM structures. The studies to date, and the prospects for practical applications of these new ideas will be discussed.

  7. ACCELERATORS: School prizes

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    Dedicated to its goal of encouraging scientists and students to work in the field of particle accelerators, the US Particle Accelerator School (operating since 1981) has switched to a new format. Starting this year, it will offer in alternate years basic accelerator physics plus advanced subjects in both university and symposium styles over four weeks. Expanding the school from two to four weeks gives additional flexibility, and undergraduate participation should be encouraged by university credits being offered for particular courses. In the intervening years, the school will organize six-day topical courses

  8. Hadron accelerators in medicine

    International Nuclear Information System (INIS)

    Amaldi, U.

    1996-01-01

    The application of hadron accelerators (protons and light ions) in cancer therapy is discussed. After a brief introduction on the rationale for the use of heavy charged particles in radiation therapy, a discussion is given on accelerator technology and beam delivery systems. Next, existing and planned facilities are briefly reviewed. The Italian Hadron-therapy Project is then described in some detail, with reference ro both the National Centre for Oncological Hadron-therapy and the design of different types of compact proton accelerators aimed at introducing proton therapy in a large umber of hospitals. (author)

  9. FMIT accelerator vacuum system

    International Nuclear Information System (INIS)

    Machalek, M.D.; Meyer, E.A.; Price, L.S.

    1979-01-01

    The Fusion Materials Irradiation Test (FMIT) Facility accelerator is being designed to continuously accelerate 100-mA deuterons to 25 MeV. High vacuum pumping of the accelerator structure and beam lines will be done by ion pumps and titanium sublimation pumps. The design of the roughing system includes a Roots blower/mechanical pump package. For economy the size of the system has been designed to operate at 10 -6 torr, where beam particle scattering on residual gases is negligible. For minimum maintenance in this neutron factory, the FMIT vacuum system is designed from the point of view of simplicity and reliability

  10. Wake field acceleration experiments

    International Nuclear Information System (INIS)

    Simpson, J.D.

    1988-01-01

    Where and how will wake field acceleration devices find use for other than, possibly, accelerators for high energy physics? I don't know that this can be responsibly answered at this time. What I can do is describe some recent results from an ongoing experimental program at Argonne which support the idea that wake field techniques and devices are potentially important for future accelerators. Perhaps this will spawn expanded interest and even new ideas for the use of this new technology. The Argonne program, and in particular the Advanced Accelerator Test Facility (AATF), has been reported in several fairly recent papers and reports. But because this is a substantially new audience for the subject, I will include a brief review of the program and the facility before describing experiments. 10 refs., 7 figs

  11. Accelerate Water Quality Improvement

    Science.gov (United States)

    EPA is committed to accelerating water quality improvement and minimizing negative impacts to aquatic life from contaminants and other stressors in the Bay Delta Estuary by working with California Water Boards to strengthen water quality improvement plans.

  12. Joint International Accelerator School

    CERN Multimedia

    CERN Accelerator School

    2014-01-01

    The CERN and US Particle Accelerator Schools recently organised a Joint International Accelerator School on Beam Loss and Accelerator Protection, held at the Hyatt Regency Hotel, Newport Beach, California, USA from 5-14 November 2014. This Joint School was the 13th in a series of such schools, which started in 1985 and also involves the accelerator communities in Japan and Russia.   Photo courtesy of Alfonse Pham, Michigan State University.   The school attracted 58 participants representing 22 different nationalities, with around half from Europe and the other half from Asia and the Americas. The programme comprised 26 lectures, each of 90 minutes, and 13 hours of case study. The students were given homework each day and had an opportunity to sit a final exam, which counted towards university credit. Feedback from the participants was extremely positive, praising the expertise and enthusiasm of the lecturers, as well as the high standard and quality of their lectures. Initial dis...

  13. Future accelerators: physics issues

    International Nuclear Information System (INIS)

    Bjorken, J.D.

    1977-11-01

    High energy physics of the future using future accelerators is discussed. The proposed machines and instruments, physics issues and opportunities including brief sketches of outstanding recent results, and the way the proposed machines address these issues are considered. 42 references

  14. Wake field acceleration experiments

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, J.D.

    1988-01-01

    Where and how will wake field acceleration devices find use for other than, possibly, accelerators for high energy physics. I don't know that this can be responsibly answered at this time. What I can do is describe some recent results from an ongoing experimental program at Argonne which support the idea that wake field techniques and devices are potentially important for future accelerators. Perhaps this will spawn expanded interest and even new ideas for the use of this new technology. The Argonne program, and in particular the Advanced Accelerator Test Facility (AATF), has been reported in several fairly recent papers and reports. But because this is a substantially new audience for the subject, I will include a brief review of the program and the facility before describing experiments. 10 refs., 7 figs.

  15. Compact particle accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Elizondo-Decanini, Juan M.

    2017-08-29

    A compact particle accelerator having an input portion configured to receive power to produce particles for acceleration, where the input portion includes a switch, is provided. In a general embodiment, a vacuum tube receives particles produced from the input portion at a first end, and a plurality of wafer stacks are positioned serially along the vacuum tube. Each of the plurality of wafer stacks include a dielectric and metal-oxide pair, wherein each of the plurality of wafer stacks further accelerate the particles in the vacuum tube. A beam shaper coupled to a second end of the vacuum tube shapes the particles accelerated by the plurality of wafer stacks into a beam and an output portion outputs the beam.

  16. The next big accelerator

    CERN Document Server

    Cramer, J G

    2002-01-01

    Accelerator physics in the US has been devastated by the cancellation of two high-energy physics colliders facilities. However there are future plans. A suggestion is made to build the new collider in the Australian outback.

  17. IAE pulsed electrostatic accelerator

    International Nuclear Information System (INIS)

    Afanas'ev, V.P.; Ganzhelyuk, M.L.; Kozlov, L.D.; Koltypin, E.A.; Molchanov, Yu.D.; Otroshchenko, G.A.; Yan'kov, G.B.

    1976-01-01

    The modernized pulse electrostatic accelerator using the klystron ion grouping and the beam interruption system prior to acceleration is described. The accelerator is modernized in order to improve parameters of a current pulse and to decrease the background in the measurement room. The ion beam of needed dimensions is obtained with the help of a high-frequency source and a beam grouping and deflection system. The general view of the beam grouping and deflection system is shown. The ion beam forming process is considered in detail. The modernized electrostatic accelerator permits to obtain a pulse current with a pulse length of 1.5 ns and an amplitude of 1.5 - 2 μA. With the repetition frequency of 2 MHz, the average target current is about 6 μA

  18. Rejuvenating CERN's Accelerators

    CERN Multimedia

    2004-01-01

    In the coming years and especially in 2005, CERN's accelerators are going to receive an extensive renovation programme to ensure they will perform reliably and effectively when the LHC comes into service.

  19. SSC accelerator availability allocation

    International Nuclear Information System (INIS)

    Dixon, K.T.; Franciscovich, J.

    1991-03-01

    Superconducting Super Collider (SSC) operational availability is an area of major concern, judged by the Central Design Group to present such risk that use of modern engineering tools would be essential to program success. Experience has shown that as accelerator beam availability falls below about 80%, efficiency of physics experiments degrades rapidly due to inability to maintain adequate coincident accelerator and detector operation. For this reason, the SSC availability goal has been set at 80%, even though the Fermi National Accelerator Laboratory accelerator, with a fraction of the SSC's complexity, has only recently approached that level. This paper describes the allocation of the top-level goal to part-level reliability and maintainability requirements, and it gives the results of parameter sensitivity studies designed to help identify the best approach to achieve the needed system availability within funding and schedule constraints. 1 ref., 12 figs., 4 tabs

  20. Pulsed Lorentz Accelerator

    Data.gov (United States)

    National Aeronautics and Space Administration — The Pulsed Lorentz Accelerator (PLA) is proposed to fill the propulsion gap for 6U and smaller satellites. The primary objective is to demonstrate the basic...

  1. Microgravity Acceleration Measurement System

    Science.gov (United States)

    Foster, William

    2009-01-01

    Microgravity Acceleration Measurement System (MAMS) is an ongoing study of the small forces (vibrations and accelerations) on the ISS that result from the operation of hardware, crew activities, as well as dockings and maneuvering. Results will be used to generalize the types of vibrations affecting vibration-sensitive experiments. Investigators seek to better understand the vibration environment on the space station to enable future research.

  2. LHCb GPU Acceleration Project

    CERN Document Server

    AUTHOR|(SzGeCERN)744808; Campora Perez, Daniel Hugo; Neufeld, Niko; Vilasis Cardona, Xavier

    2016-01-01

    The LHCb detector is due to be upgraded for processing high-luminosity collisions, which will increase the load on its computation infrastructure from 100 GB/s to 4 TB/s, encouraging us to look for new ways of accelerating the Online reconstruction. The Coprocessor Manager is our new framework for integrating LHCb’s existing computation pipelines with massively parallel algorithms running on GPUs and other accelerators. This paper describes the system and analyzes its performance.

  3. Ion optics for accelerators

    International Nuclear Information System (INIS)

    Enge, H.A.

    1974-01-01

    A review is given of ion-optic devices used in particle accelerators, including electrostatic lenses, magnetic quadrupoles, and deflecting magnets. Tube focusing in dc accelerators is also treated, and a novel scheme for shaping the electrodes to produce strong focusing is described. The concepts of emittance (phase space) and emittance conservation are briefly discussed. Chromatic and spatial aberrations are introduced, and it is shown how they can be calculated and sometimes substantially reduced. Some examples are given

  4. A symmetrical rail accelerator

    International Nuclear Information System (INIS)

    Igenbergs, E.

    1991-01-01

    This paper reports on the symmetrical rail accelerator that has four rails, which are arranged symmetrically around the bore. The opposite rails have the same polarity and the adjacent rails the opposite polarity. In this configuration the radial force acting upon the individual rails is significantly smaller than in a conventional 2-rail configuration and a plasma armature is focussed towards the axis of the barrel. Experimental results indicate a higher efficiency compared to a conventional rail accelerator

  5. An active particle accelerator

    International Nuclear Information System (INIS)

    Goldman, T.

    1991-01-01

    Although a static charge is difficult to maintain on macroscopic particles, it is straightforward to construct a small object with a regularly oscillating electric dipole moment. For objects of a given size, one may then construct an accelerator by appropriately matching the frequency and separations of an external array of electrodes to this size. Physically feasible size ranges, an accelerator design, and possible applications of such systems are discussed. 8 refs., 9 figs

  6. Accelerating News Issue 2

    CERN Document Server

    Kahle, K; Wildner, E

    2012-01-01

    In this summer issue we look at how developments in collimator materials could have applications in aerospace and beyond, and how Polish researchers are harnessing accelerators for medical and industrial uses. We see how the LHC luminosity upgrade is linking with European industry and US researchers, and how the neutrino oscillation community is progressing. We find out the mid-term status of TIARA-PP and how it is mapping European accelerator education resources.

  7. Collective Ion Acceleration.

    Science.gov (United States)

    1980-01-01

    flash x- _ ray sources may require, for maximum x-ray yield. t Pulsed-power systems using Van de Graaff generators are also in use. They are less common... generation and collective ion acceleration. A more recent effort has been initi- II ated to investigate proton acceleration in Induction Linacs. The...original contract supported the study of microwave generation using slow wave structures and study of a free electron laser configuration. About 1 alfway

  8. Vancouver Accelerator Conference

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    Anyone who contends that particle physics is conducted in an ivory tower, not contributing to other fields of science or to humanity at large, should have attended the 1985 Particle Accelerator Conference in Vancouver. Over a thousand participants contributed 781 papers and only a fraction were actually related to accelerators for high energy physics. The majority of present developments are in the service of other fields of science, for alternative power sources, for medicine, for industrial applications, etc

  9. High energy medical accelerators

    International Nuclear Information System (INIS)

    Mandrillon, P.

    1990-01-01

    The treatment of tumours with charged particles, ranging from protons to 'light ions' (carbon, oxygen, neon), has many advantages, but up to now has been little used because of the absence of facilities. After the successful pioneering work carried out with accelerators built for physics research, machines dedicated to this new radiotherapy are planned or already in construction. These high energy medical accelerators are presented in this paper. (author) 15 refs.; 14 figs.; 8 tabs

  10. Laser wakefield acceleration

    International Nuclear Information System (INIS)

    Esarey, E.; Ting, A.; Sprangle, P.

    1989-01-01

    The laser wakefield accelerator (LWFA) is a novel plasma based electron acceleration scheme which utilizes a relativistic optical guiding mechanism for laser pulse propagation. In the LWFA, a short, high power, single frequency laser pulse is propagated through a plasma. As the laser pulse propagates, its radial and axial ponderomotive forces nonresonantly generate large amplitude plasma waves (wakefields) with a phase velocity equal to the group velocity of the pulse. A properly phased electron bunch may then be accelerated by the axial wakefield and focused by the transverse wakefield. Optical guiding of the laser pulse in the plasma is necessary in order to achieve high energies in a single stage of acceleration. At sufficiently high laser powers, optical guiding may be achieved through relativistic effects associated with the plasma electrons. Preliminary analysis indicates that this scheme may overcome some of the difficulties present in the plasma beat wave accelerator and in the plasma wakefield accelerator. Analytical and numerical calculations are presented which study both laser pulse propagation within a plasma as well as the subsequent generation of large amplitude plasma waves. In addition, the generation of large amplitude plasma waves in regimes where the plasma waves become highly nonlinear is examined

  11. Accelerator business in Japan expanding

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    Accelerators have become to be used increasingly in Japan in such fields as medicine, physics research and industry. This has caused stiff competition for market share by the manufacturers of accelerators. Electron beam accelerators for industrial use provide an indispensable means for adding values to products, for example, electric cables with incombustible insulators. Linear accelerators for the nondestructive inspection of nuclear components have been widely installed at equipment manufacturing plants. Active efforts have been exerted to develop small synchrotron radiation accelerators for next generation electronic industry. Cyclotrons for producing short life radioisotopes for medical diagnosis and electron beam accelerators for radiation therapy are also used routinely. The suppliers of accelerators include the companies manufacturing heavy electric machinery, heavy machinery and the engineering division of steelmakers. Accelerator physics is being formed, but universities do not yet offer the course regarding accelerators. Accelerator use in Japan and the trend of accelerator manufacturers are reported. (K.I.)

  12. Beam transport through electrostatic accelerators and matching into post accelerators

    International Nuclear Information System (INIS)

    Larson, J.D.

    1986-01-01

    Ion beam transport through electrostatic acceleration is briefly reviewed. Topics discussed include injection, matching into the low-energy acceleration stage, matching from the terminal stripper into the high-energy stage, transport to a post accelerator, space charge, bunching isochronism, dispersion and charge selection. Beam transport plans for the proposed Vivitron accelerator are described. (orig.)

  13. Small type accelerator. Try for accelerator driven system

    CERN Document Server

    Mori, Y

    2003-01-01

    FFAG (Fixed-field alternating gradient) accelerator for accelerator driven subcritical reactor, which aims to change from long-lived radioactive waste to short-lived radioactivity, is introduced. It is ring accelerator. The performance needed is proton as accelerator particle, 10MW (total) beam power, about 1GeV beam energy, >30% power efficiency and continuous beam. The feature of FFAG accelerator is constant magnetic field. PoP (Proof-of-principle)-FFAG accelerator, radial type, was run at first in Japan in 2000. The excursion is about some ten cm. In principle, beam can be injected and extracted at any place of ring. The 'multi-fish' acceleration can accelerate beams to 100% duty by repeating acceleration. 150MeV-FFAG accelerator has been started since 2001. It tried to practical use, for example, treatment of cancer. (S.Y.)

  14. Linear induction accelerators

    International Nuclear Information System (INIS)

    Briggs, R.J.

    1986-06-01

    The development of linear induction accelerators has been motivated by applications requiring high-pulsed currents of charged particles at voltages exceeding the capability of single-stage, diode-type accelerators and at currents too high for rf accelerators. In principle, one can accelerate charged particles to arbitrarily high voltages using a multi-stage induction machine, but the 50-MeV, 10-kA Advanced Test Accelerator (ATA) at LLNL is the highest voltage machine in existence at this time. The advent of magnetic pulse power systems makes sustained operation at high-repetition rates practical, and this capability for high-average power is very likely to open up many new applications of induction machines in the future. This paper surveys the US induction linac technology with primary emphasis on electron machines. A simplified description of how induction machines couple energy to the electron beam is given, to illustrate many of the general issues that bound the design space of induction linacs

  15. Linear induction accelerators

    International Nuclear Information System (INIS)

    Briggs, R.J.

    1986-01-01

    The development of linear induction accelerators has been motivated by applications requiring high-pulsed currents of charged particles at voltages exceeding the capability of single-stage, diode-type accelerators and at currents too high for r.f. accelerators. In principle, one can accelerate charged particles to arbitrarily high voltages using a multi-stage induction machine, but the 50-MeV, 10-kA Advanced Test Accelerator (ATA) at LLNL is the highest voltage machine in existence at this time. The advent of magnetic pulse power systems makes sustained operation at high-repetition rates practical, and this capability for high-average power in very likely to open up many new applications of induction machines in the future. The US induction linac technology is surveyed with primary emphasis on electron machines. A simplified description of how induction machines couple energy to the electron beam is given, to illustrate many of the general issues that bound the design space of induction linacs. A key issue in all high-intensity linacs is that of beam instability

  16. Accelerators for atomic energy research

    International Nuclear Information System (INIS)

    Shibata, Tokushi

    1999-01-01

    The research and educational activities accomplished using accelerators for atomic energy research were studied. The studied items are research subjects, facility operation, the number of master theses and doctor theses on atomic energy research using accelerators and the future role of accelerators in atomic energy research. The strategy for promotion of the accelerator facility for atomic energy research is discussed. (author)

  17. Accelerators in Science and Technology

    CERN Document Server

    Kailas, S

    2002-01-01

    Accelerators built for basic research in frontier areas of science have become important and inevitable tools in many areas of science and technology. Accelerators are examples of science driven high technology development. Accelerators are used for a wide ranging applications, besides basic research. Accelerator based multidisciplinary research holds great promise

  18. Plasma-based accelerator structures

    International Nuclear Information System (INIS)

    Schroeder, Carl B.

    1999-01-01

    Plasma-based accelerators have the ability to sustain extremely large accelerating gradients, with possible high-energy physics applications. This dissertation further develops the theory of plasma-based accelerators by addressing three topics: the performance of a hollow plasma channel as an accelerating structure, the generation of ultrashort electron bunches, and the propagation of laser pulses is underdense plasmas

  19. Z-guggulsterone negatively controls microglia-mediated neuroinflammation via blocking IκB-α-NF-κB signals.

    Science.gov (United States)

    Huang, Chao; Wang, Jili; Lu, Xu; Hu, Wenfeng; Wu, Feng; Jiang, Bo; Ling, Yong; Yang, Rongrong; Zhang, Wei

    2016-04-21

    Induction of pro-inflammatory factors is one of the characteristics of microglial activation and can be regulated by numerous active agents extracted from plants. Suppression of pro-inflammatory factors is beneficial to alleviate neuroinflammation. Z-guggulsterone, a compound extracted from the gum resin of the tree commiphora mukul, exhibits numerous anti-inflammatory effects. However, the role and mechanism of Z-guggulsterone in pro-inflammatory responses in microglia remains unclear. This study addressed this issue in in vitro murine microglia and in vivo neuroinflammation models. Results showed that Z-guggulsterone reduced inducible nitric oxide (iNOS) protein expression as well as nitric oxide (NO), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) production in LPS-stimulated BV-2 cells. Z-guggulsterone also reduced the mRNA level of iNOS, TNF-α, and IL-6. Mechanistic studies revealed that Z-guggulsterone attenuated the LPS-induced degradation of inhibitor κ B-α (IκB-α) as well as the LPS-induced nuclear translocation of nuclear factor-κB (NF-κB). Z-guggulsterone, however, failed to reduce the LPS-induced increase in NF-κB phosphorylation level. These major findings were ascertained in primary microglia where the LPS-induced increases in iNOS expression, NO content, and IκB-α degradation were diminished by Z-guggulsterone treatment. In a mouse model of neuroinflammation, Z-guggulsterone exhibited significant anti-inflammatory effects, which were exemplified by the attenuation of microglial activation and neuroinflammation-induced behavioral abnormalities in Z-guggulsterone-treated mice. Taken together, these studies demonstrate that Z-guggulsterone attenuates the LPS-mediated induction of pro-inflammatory factors in microglia via inhibition of IκB-α-NF-κB signals, providing evidence to uncover the potential role of Z-guggulsterone in neuroinflammation-associated disorder therapies. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  20. microRNA-200b modulates microglia-mediated neuroinflammation via the cJun/MAPK pathway.

    Science.gov (United States)

    Jadhav, Shweta P; Kamath, Sandhya P; Choolani, Mahesh; Lu, Jia; Dheen, S Thameem

    2014-08-01

    Chronic activation of microglia, the macrophages of the CNS, has been shown to enhance neuronal damage because of excessive release of proinflammatory cytokines and neurotoxic molecules in a number of neurodegenerative diseases. Recent reports showed altered microRNA (miRNA) expression in immune-mediated pathologies, thus suggesting that miRNAs modulate expression of genes involving immune responses. This study demonstrates that miRNA-200b is expressed in microglia and modulates inflammatory response of microglia by regulating mitogen-activated protein kinase pathway. miRNA-200b expression was found to be down-regulated in activated microglia in vivo (traumatic brain injury rat model) and in vitro. A luciferase assay and loss- and gain-of-function studies revealed c-Jun, the transcription factor of cJun-N terminal kinase (JNK) mitogen-activated protein kinase pathway to be the target of miR-200b. Knockdown of miR-200b in microglia increased JNK activity along with an increase in pro-inflammatory cytokines, inducible nitric oxide synthase expression and nitric oxide (NO) production. Conversely, over-expression of miRNA-200b in microglia resulted in a decrease in JNK activity, inducible nitric oxide synthase expression, NO production and migratory potential of activated microglia. Furthermore, miR-200b inhibition resulted in increased neuronal apoptosis after treatment of neuronal cells with conditioned medium obtained from microglial culture. Taken together, these results indicate that miRNA-200b modulates microglial inflammatory process including cytokine secretion, NO production, migration and neuronal survival. © 2014 International Society for Neurochemistry.

  1. 20170821 - Computational modeling of the neurovascular unit to predict microglia mediated effects on blood-brain barrier formation (WC10)

    Science.gov (United States)

    Development of the neurovascular unit (NVU) involves interactions between endothelial cells, pericytes, neuroprogenitor cells, and microglia. We constructed an in silico model of the developing neuroepithelium in CompuCell3D which recapitulated a suite of critical signaling pathw...

  2. Acceleration of magnetized plasma rings

    International Nuclear Information System (INIS)

    Hartman, D.; Eddleman, J.; Hammer, J.H.

    1982-01-01

    One scheme is considered, acceleration of a ring between coaxial electrodes by a B/sub theta/ field as in a coaxial rail-gun. If the electrodes are conical, a ring accelerated towards the apex of the cone undergoes self-similar compression (focussing) during acceleration. Because the allowable acceleration force F/sub a/ = kappa U/sub m//R (kappa - 2 , the accelerating distance for conical electrodes is considerably shortened over that required for coaxial electrodes. In either case however, since the accelerating flux can expand as the ring moves, most of the accelerating field energy can be converted into kinetic energy of the ring leading to high efficiency

  3. Artificial seismic acceleration

    Science.gov (United States)

    Felzer, Karen R.; Page, Morgan T.; Michael, Andrew J.

    2015-01-01

    In their 2013 paper, Bouchon, Durand, Marsan, Karabulut, 3 and Schmittbuhl (BDMKS) claim to see significant accelerating seismicity before M 6.5 interplate mainshocks, but not before intraplate mainshocks, reflecting a preparatory process before large events. We concur with the finding of BDMKS that their interplate dataset has significantly more fore- shocks than their intraplate dataset; however, we disagree that the foreshocks are predictive of large events in particular. Acceleration in stacked foreshock sequences has been seen before and has been explained by the cascade model, in which earthquakes occasionally trigger aftershocks larger than themselves4. In this model, the time lags between the smaller mainshocks and larger aftershocks follow the inverse power law common to all aftershock sequences, creating an apparent acceleration when stacked (see Supplementary Information).

  4. JKJ accelerator timing system

    International Nuclear Information System (INIS)

    Ohmori, C.; Mori, Y.; Yoshii, M.; Yamamoto, M.

    2001-01-01

    The JKJ (JAERl-KEK Joint Project) accelerator complex consists of the linear accelerator, 3 GeV and 50 GeV synchrotrons. To minimize the beam loss during the beam transfer from the 3 GeV synchrotron to the 50 GeV one, the synchronization of the two RF system of the rings is very important. To reduce the background from the high and low momentum neutron, the neutron beam chopper will be employed. The 3 GeV RF will be also synchronized to the chopper timing when the beam goes to the neutron facility. The whole timing control system of these accelerators and chopper will be described. (author)

  5. Particle accelerator physics

    CERN Document Server

    Wiedemann, Helmut

    2007-01-01

    Particle Accelerator Physics is an in-depth and comprehensive introduction to the field of high-energy particle acceleration and beam dynamics. Part I gathers the basic tools, recalling the essentials of electrostatics and electrodynamics as well as of particle dynamics in electromagnetic fields. Part II is an extensive primer in beam dynamics, followed in Part III by the introduction and description of the main beam parameters. Part IV is devoted to the treatment of perturbations in beam dynamics. Part V discusses the details of charged particle accleration. Part VI and Part VII introduce the more advanced topics of coupled beam dynamics and the description of very intense beams. Part VIII is an exhaustive treatment of radiation from accelerated charges and introduces important sources of coherent radiation such as synchrotrons and free-electron lasers. Part IX collects the appendices gathering useful mathematical and physical formulae, parameters and units. Solutions to many end-of-chapter problems are give...

  6. Medical uses of accelerators

    International Nuclear Information System (INIS)

    Bradbury, J.N.

    1981-01-01

    A variety of particle accelerators have either potential or already demonstrated uses in connection with medically-related research, diagnosis, and treatment. For cancer radiotherapy, nuclear particles including protons, neutrons, heavy ions, and negative pi mesons have advantages compared to conventional radiations in terms of dose localization and/or biological effectiveness. Clinical evaluations of these particles are underway at a number of institutions. Accelerator-produced radionuclides are in widespread use for research and routine diagnostic purposes. Elemental analysis techniques with charged particles and neutrons are being applied to bone, blood, and other tissues. Finally, low-dose medical imaging can be accomplished with accelerated protons and heavy ions. The status and future of these programs are discussed

  7. Universality of accelerating change

    Science.gov (United States)

    Eliazar, Iddo; Shlesinger, Michael F.

    2018-03-01

    On large time scales the progress of human technology follows an exponential growth trend that is termed accelerating change. The exponential growth trend is commonly considered to be the amalgamated effect of consecutive technology revolutions - where the progress carried in by each technology revolution follows an S-curve, and where the aging of each technology revolution drives humanity to push for the next technology revolution. Thus, as a collective, mankind is the 'intelligent designer' of accelerating change. In this paper we establish that the exponential growth trend - and only this trend - emerges universally, on large time scales, from systems that combine together two elements: randomness and amalgamation. Hence, the universal generation of accelerating change can be attained by systems with no 'intelligent designer'.

  8. Superconducting Accelerator Magnets

    CERN Document Server

    Mess, K H; Wolff, S

    1996-01-01

    The main topic of the book are the superconducting dipole and quadrupole magnets needed in high-energy accelerators and storage rings for protons, antiprotons or heavy ions. The basic principles of low-temperature superconductivity are outlined with special emphasis on the effects which are relevant for accelerator magnets. Properties and fabrication methods of practical superconductors are described. Analytical methods for field calculation and multipole expansion are presented for coils without and with iron yoke. The effect of yoke saturation and geometric distortions on field quality is studied. Persistent magnetization currents in the superconductor and eddy currents the copper part of the cable are analyzed in detail and their influence on field quality and magnet performance is investigated. Superconductor stability, quench origins and propagation and magnet protection are addressed. Some important concepts of accelerator physics are introduced which are needed to appreciate the demanding requirements ...

  9. Tandem accelerator operation

    International Nuclear Information System (INIS)

    Rummel, R.L.; Carter, E.P.; Westerfeldt, C.R.

    1985-01-01

    For the period July 1, 1984 through July 31, 1985 the FN tandem accelerator was operated for 6760 hours. This represents 72% utilization of the maximum available machine time for the past 13 months. The total running time for this machine is now 104,470 hours, and the age of two of the accelerator tubes exceeds 100,000 hours. In August of last year the authors removed the liquid-nitrogen trapped mercury diffusion pump on the low energy end of the accelerator. In its place the authors installed a Varian Cryostack cryopump along with a new NEC beam scanner, a new set of beam chopper plates, and new vacuum gauges and protection circuits. The vacuum in the low energy tube has been improved from 5 x 10 -6 to 5 x 10 -7 Torr

  10. Accelerators for therapy

    International Nuclear Information System (INIS)

    Pohlit, W.

    1994-01-01

    In the past decades circular and linear electron accelerators have been developed for clinical use in radiation therapy of tumors with the aim of achieving a high radiation dose in the tumor and as low as possible dose in the adjacent normal tissues. Today about one thousand accelerators are in medical use throughout the world and many hundred thousand patients are treated every day with accelerator-produced radiation. There exists, however, a large number of patients who cannot be treated satisfactorily in this way. New types of radiations such as neutrons, negative pions, protons and heavy ions were therefore tested recently. The clinical experience with these radiations and with new types of treatment procedures indicate that in future the use of a scanning beam of high energy protons might be optimal for the treatment of tumors. (orig.)

  11. Incineration by accelerator

    International Nuclear Information System (INIS)

    Cribier, M.; FIoni, G.; Legrain, R.; Lelievre, F.; Leray, S.; Pluquet, A.; Safa, H.; Spiro, M.; Terrien, Y.; Veyssiere, Ch.

    1997-01-01

    The use MOX fuel allows to hope a stabilization of plutonium production around 500 tons for the French park. In return, the flow of minor actinides is increased to several tons. INCA (INCineration by Accelerator), dedicated instrument, would allow to transmute several tons of americium, curium and neptunium. It could be able to reduce nuclear waste in the case of stopping nuclear energy use. This project needs: a protons accelerator of 1 GeV at high intensity ( 50 m A), a window separating the accelerator vacuum from the reactor, a spallation target able to produce 30 neutrons by incident proton, an incineration volume where a part of fast neutrons around the target are recovered, and a thermal part in periphery with flows at 2.10 15 n/cm 2 .s; a chemical separation of elements burning in thermal (americium) from the elements needing a flow of fast neutrons. (N.C.)

  12. Accelerator technology in tokamaks

    International Nuclear Information System (INIS)

    Kustom, R.L.

    1977-01-01

    This article presents the similarities in the technology required for high energy accelerators and tokamak fusion devices. The tokamak devices and R and D programs described in the text represent only a fraction of the total fusion program. The technological barriers to producing successful, economical tokamak fusion power plants are as many as the plasma physics problems to be overcome. With the present emphasis on energy problems in this country and elsewhere, it is very likely that fusion technology related R and D programs will vigorously continue; and since high energy accelerator technology has so much in common with fusion technology, more scientists from the accelerator community are likely to be attracted to fusion problems

  13. Accelerating the culture change!

    Science.gov (United States)

    Klunk, S W; Panetta, J; Wooten, J

    1996-11-01

    Exide Electronics, a major supplier of uninterruptible power system equipment, embarked on a journey of changing a culture to improve quality, enhance customer responsiveness, and reduce costs. This case study examines the evolution of change over a period of seven years, with particular emphasis on the most recent years, 1992 through 1995. The article focuses on the Raleigh plant operations and describes how each succeeding year built on the successes and fixed the shortcomings of the prior years to accelerate the culture change, including corrective action and continuous improvement processes, organizational structures, expectations, goals, achievements, and pitfalls. The real challenge to changing the culture was structuring a dynamic approach to accelerate change! The presentation also examines how the evolutionary process itself can be created and accelerated through ongoing communication, regular feedback of progress and goals, constant evaluation and direction of the process, and measuring and paying for performance.

  14. CERN: Accelerator school

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    Full text: Jyvaskyla, a university town in central Finland, was the setting for last year's General Accelerator School organized by the CERN Accelerator School. Well over a hundred students - more than for some time - followed two weeks of lectures on a broad spectrum of accelerator topics, the first step en route to becoming the designers, builders and operators of the surprisingly large number of, accelerators of all kinds either built or planned throughout Europe and further afield. This was the fifth such school organized by CAS in a biennial cycle which alternates this introductory level with more advanced tuition. The next, advanced, school will be from 20 October - 1 November, hosted by Athens University on the Greek Island of Rhodes. (Application details will become available in Spring but would-be participants should already reserve the dates.) After Finland, the CAS caravan moved to Benalmadena near Malaga in Spain where, together with Seville University, they organized one of the joint US-CERN schools held every two years and focusing on frontier accelerator topics. This time the subject was electron-positron factories - machines for high luminosity experiments in phi, tau-charm, beauty and Z physics. Experts from both sides of the Atlantic and from Japan shared their knowledge with an equally representative audience and probed the many intensity related phenomena which must be mastered to reach design performance. A number of these topics will receive extended coverage in the next specialist CAS School which is a repeat - by public demand - of the highly successful radiofrequency course held in Oxford in 1991. This school will be in Capri, Italy, with the support of the University of Naples from 29 April to 5 May. Details and application forms are now available by e-mail (CASRF@CERNVM.CERN.CH), by fax (+41 22 7824836) or from Suzanne von Wartburg, CERN Accelerator School, 1211 Geneva 23, Switzerland

  15. Photocathodes in accelerator applications

    International Nuclear Information System (INIS)

    Fraser, J.S.; Sheffield, R.L.; Gray, E.R.; Giles, P.M.; Springer, R.W.; Loebs, V.A.

    1987-01-01

    Some electron accelerator applications require bursts of short pulses at high microscopic repetition rates and high peak brightness. A photocathode, illuminated by a mode-locked laser, is well suited to filling this need. The intrinsic brightness of a photoemitter beam is high; experiments are under way at Los Alamos to study the brightness of short bunches with high space charge after acceleration. A laser-illuminated Cs 3 Sb photoemitter is located in the first rf cavity of an injector linac. Diagnostics include a pepper-pot emittance analyzer, a magnetic spectrometer, and a streak camera

  16. Shielding high energy accelerators

    CERN Document Server

    Stevenson, Graham Roger

    2001-01-01

    After introducing the subject of shielding high energy accelerators, point source, line-of-sight models, and in particular the Moyer model. are discussed. Their use in the shielding of proton and electron accelerators is demonstrated and their limitations noted. especially in relation to shielding in the forward direction provided by large, flat walls. The limitations of reducing problems to those using it cylindrical geometry description are stressed. Finally the use of different estimators for predicting dose is discussed. It is suggested that dose calculated from track-length estimators will generally give the most satisfactory estimate. (9 refs).

  17. Accelerated cyclic corrosion tests

    Directory of Open Access Journals (Sweden)

    Prošek T.

    2016-06-01

    Full Text Available Accelerated corrosion testing is indispensable for material selection, quality control and both initial and residual life time prediction for bare and painted metallic, polymeric, adhesive and other materials in atmospheric exposure conditions. The best known Neutral Salt Spray (NSS test provides unrealistic conditions and poor correlation to exposures in atmosphere. Modern cyclic accelerated corrosion tests include intermittent salt spray, wet and dry phases and eventually other technical phases. They are able to predict the material performance in service more correctly as documented on several examples. The use of NSS should thus be restricted for quality control.

  18. Interfacing to accelerator instrumentation

    International Nuclear Information System (INIS)

    Shea, T.J.

    1995-01-01

    As the sensory system for an accelerator, the beam instrumentation provides a tremendous amount of diagnostic information. Access to this information can vary from periodic spot checks by operators to high bandwidth data acquisition during studies. In this paper, example applications will illustrate the requirements on interfaces between the control system and the instrumentation hardware. A survey of the major accelerator facilities will identify the most popular interface standards. The impact of developments such as isochronous protocols and embedded digital signal processing will also be discussed

  19. Remarks on stochastic acceleration

    International Nuclear Information System (INIS)

    Graeff, P.

    1982-12-01

    Stochastic acceleration and turbulent diffusion are strong turbulence problems since no expansion parameter exists. Hence the problem of finding rigorous results is of major interest both for checking approximations and for reference models. Since we have found a way of constructing such models in the turbulent diffusion case the question of the extension to stochastic acceleration now arises. The paper offers some possibilities illustrated by the case of 'stochastic free fall' which may be particularly interesting in the context of linear response theory. (orig.)

  20. Accelerating time to benefit

    DEFF Research Database (Denmark)

    Svejvig, Per; Geraldi, Joana; Grex, Sara

    of the time. Although all cases valued speed and speed to benefit, and implemented most practices proposed by the methodology, only three of the five projects were more successful in decreasing time to speed. Based on a multi-case study comparison between these five different projects and their respective......Despite the ubiquitous pressure for speed, our approaches to accelerate projects remain constrained to the old-fashioned understanding of the project as a vehicle to deliver products and services, not value. This article explores an attempt to accelerate time to benefit. We describe and deconstruct...

  1. Spallator - accelerator breeder

    International Nuclear Information System (INIS)

    Steinberg, M.

    1985-01-01

    The concept involves the use of spallation neutrons produced by interaction of a high energy proton (1 to 2 GeV) from a linear accelerator (LINAC) with a heavy metal target (uranium). The principal spallator concept is based on generating fissile fuel for use in LWR nuclear power plants. The spallator functions in conjunction with a reprocessing plant to regenerate and produce the Pu-239 or U-233 for fabrication into fresh LWR reactor fuel elements. Advances in proton accelerator technology has provided a solid base for predicting performance and optimizing the design of a reliable, continuous wave, high-current LINAC required by a fissile fuel production machine

  2. Accelerator terminal voltage stability

    Science.gov (United States)

    Ferry, J. A.; Kolonko, J. J.; Phillips, S. H.; Lunstrum, S. J.

    1992-02-01

    Measurements reported at the 11th International Conference on Applications of Accelerators in Research and Industry [Schroeder et al., Nucl. Instr. and Meth. B56/B57 (1991) 1033] for a 1 MV single-ended Pelletron accelerator equipped with corona probe and tank liner voltage stabilizers have been extended by measuring the resonant yield of γ-rays from the 27Al(p, γ) 28Si reaction at 992 keV. Results show that terminal voltage stability is consistent with the earlier measurement of 31 V FWHM for ripple at 1 MV for periods of about one-half ( {1}/{2}) hour.

  3. Accelerator terminal voltage stability

    International Nuclear Information System (INIS)

    Ferry, J.A.; Kolonko, J.J.; Phillips, S.H.; Lunstrum, S.J.

    1992-01-01

    Measurements reported at the 11th International Conference on Applications of Accelerators in Research and Industry for a 1 MV single-ended Pelletron accelerator equipped with corona probe and tank liner voltage stabilizers have been extended by measuring the resonant yield of γ-rays from the 27 Al(p,γ) 28 Si reaction at 992 keV. Results show that terminal voltage stability is consistent with the earlier measurement of 31 V FWHM for ripple at 1 MV for periods of about one-half (1/2) hour. (orig.)

  4. Accelerating News Issue 4

    CERN Document Server

    Szeberenyi, A; Wildner, E

    2012-01-01

    In this winter issue, we are very pleased to announce the approval of EuCARD-2 by the European Commission. We look at the conclusions of EUROnu in proposing future neutrino facilities at CERN, a new milestone reached by CLIC and progress on the SPARC upgrade using C-band technology. We also report on recent events: second Joint HiLumi LHC-LARP Annual Meeting and workshop on Superconducting technologies for the Next Generation of Accelerators aiming at closer collaboration with industry. The launch of the Accelerators for Society brochure is also highlighted.

  5. Pulsed Drift Tube Accelerator

    International Nuclear Information System (INIS)

    Faltens, A.

    2004-01-01

    The pulsed drift-tube accelerator (DTA) concept was revived by Joe Kwan and John Staples and is being considered for the HEDP/WDM application. It could be used to reach the full energy or as an intermediate accelerator between the diode and a high gradient accelerator such as multi-beam r.f. In the earliest LBNL HIF proposals and conceptual drivers it was used as an extended injector to reach energies where an induction linac with magnetic quadrupoles is the best choice. For HEDP, because of the very short pulse duration, the DTA could provide an acceleration rate of about 1MV/m. This note is divided into two parts: the first, a design based on existing experience; the second, an optimistic extrapolation. The first accelerates 16 parallel K + beams at a constant line charge density of 0.25(micro) C/m per beam to 10 MeV; the second uses a stripper and charge selector at around 4MeV followed by further acceleration to reach 40 MeV. Both benefit from more compact sources than the present 2MV injector source, although that beam is the basis of the first design and is a viable option. A pulsed drift-tube accelerator was the first major HIF experiment at LBNL. It was designed to produce a 2(micro)s rectangular 1 Ampere C s + beam at 2MeV. It ran comfortably at 1.6MeV for several years, then at lower voltages and currents for other experiments, and remnants of that experiment are in use in present experiments, still running 25 years later. The 1A current, completely equivalent to 1.8A K + , was chosen to be intermediate between the beamlets appropriate for a multi-beam accelerator, and a single beam of, say, 10A, at injection energies. The original driver scenarios using one large beam on each side of the reactor rapidly fell out of favor because of the very high transverse and longitudinal fields from the beam space charge, circa 1MV/cm and 250 kV/cm respectively, near the chamber and because of aberrations in focusing a large diameter beam down to a 1mm radius spot at a

  6. Cockroft Walton accelerator prototype

    International Nuclear Information System (INIS)

    Hutapea, Sumihar.

    1976-01-01

    Prototype of a Cockroft Walton generator using ceramic and plastic capacitors is discussed. Compared to the previous generator, the construction and components are much more improved. Pralon is used for the high voltage insulation column and plastic is used as a dielectric material for the high voltage capacitor. Cockroft Walton generator is used as a high tension supply for an accelerator. (author)

  7. Next generation of accelerators

    International Nuclear Information System (INIS)

    Richter, B.

    1979-01-01

    Existing high-energy accelerators are reviewed, along with those under construction or being designed. Finally, some of the physics issues which go into setting machine parameters, and some of the features of the design of next generation electron and proton machines are discussed

  8. The ATOMKI Accelerator Center

    International Nuclear Information System (INIS)

    Biri, S.; Kormany, Z.; Berzi, I.; Hunyadi, M.

    2009-01-01

    In 2009 a new division was established in our institute: the ATOMKI Accelerator Center (AAC). Before this time the facilities and staff of AAC belonged to other departments of the institute. The re-organization however, was necessary. It was understood that the translocation of all the accelerators into a centralized unit is advantageous in numerous fields. Here we just mention some of them. The submission of any instrumentation type proposal (EU or domestic) will be easier and has a higher chance to be supported. The organization and distribution of the beamtimes will be more equal and optimal. The usage of the maintenance and spare tools can became better and cheaper. The operating staff (cca. 20 person) can serve at more than one accelerator and the teams can help each other. The accelerator center actually became a fourth new basic unit of the institute besides the three traditional scientific divisions (see the Atomki homepage for the organization chart). The following six main facilities belong to the accelerator center: Cyclotron; VdG-5 accelerator; VdG-1 accelerator; ECR ion source; Isotope separator; Tandetron (under installation). In figure 1 the placements of these machines are shown in an artistic 3D map of the Atomki. The table 1 summarizes the main parameters of the accelerators. More detailed technical specification of the machines can be found in the new homepage of the center. In 2009 all the accelerators operated as scheduled, safely and without major breakdowns. After the experiences in the first months it can be concluded that the new center works well both for technical and human point of views. In the next sub-chapters the 2009 operation and development details of the individual accelerators are summarized. Cyclotron operation. The operation of the cyclotron in 2009 was concentrated to the usual 9 months; January, July and August were reserved for maintenance and holidays. The overall working time of the accelerator was 2009 hours; the time

  9. The CERN accelerator complex

    CERN Multimedia

    Christiane Lefèvre

    2008-01-01

    The LHC is the last ring (dark grey line) in a complex chain of particle accelerators. The smaller machines are used in a chain to help boost the particles to their final energies and provide beams to a whole set of smaller experiments, which also aim to uncover the mysteries of the Universe.

  10. Hamburg Accelerator Conference

    International Nuclear Information System (INIS)

    Wilson, Edmund J.N.

    1992-01-01

    From 20-24 July, Hamburg welcomed the Fifteenth International Conference on High Energy Accelerators (HEACC). A natural highlight was the recent commissioning success of the HERA electron-proton collider at Hamburg's DESY Laboratory and its first high energy electron-proton collision data. This gave the meeting the feel of a family event celebrating a newborn

  11. The Bevalac accelerator

    International Nuclear Information System (INIS)

    Dacal, A.

    1989-01-01

    Presented are the characteristics of the Bevatron and SuperHilac heavy ion accelerators in a very general manner. Some aspects of their application in the field of biological medicine and some of the interesting results obtained in experiments on nuclear physics are mentioned. (Author). 20 refs, 2 figs, 2 tabs

  12. The CERN accelerator complex

    CERN Multimedia

    Mobs, Esma Anais

    2016-01-01

    The LHC is the last ring (dark blue line) in a complex chain of particle accelerators. The smaller machines are used in a chain to help boost the particles to their final energies and provide beams to a whole set of smaller experiments, which also aim to uncover the mysteries of the Universe.

  13. The CERN accelerator complex

    CERN Multimedia

    Haffner, Julie

    2013-01-01

    The LHC is the last ring (dark grey line) in a complex chain of particle accelerators. The smaller machines are used in a chain to help boost the particles to their final energies and provide beams to a whole set of smaller experiments, which also aim to uncover the mysteries of the Universe.

  14. Prospects for Accelerator Technology

    Science.gov (United States)

    Todd, Alan

    2011-02-01

    Accelerator technology today is a greater than US$5 billion per annum business. Development of higher-performance technology with improved reliability that delivers reduced system size and life cycle cost is expected to significantly increase the total accelerator technology market and open up new application sales. Potential future directions are identified and pitfalls in new market penetration are considered. Both of the present big market segments, medical radiation therapy units and semiconductor ion implanters, are approaching the "maturity" phase of their product cycles, where incremental development rather than paradigm shifts is the norm, but they should continue to dominate commercial sales for some time. It is anticipated that large discovery-science accelerators will continue to provide a specialty market beset by the unpredictable cycles resulting from the scale of the projects themselves, coupled with external political and economic drivers. Although fraught with differing market entry difficulties, the security and environmental markets, together with new, as yet unrealized, industrial material processing applications, are expected to provide the bulk of future commercial accelerator technology growth.

  15. Accelerating with industry

    International Nuclear Information System (INIS)

    Southworth, Brian

    1992-01-01

    At the end of March, Berlin was the scene of the third biennial European Particle Accelerator Conference (EPAC). It carried the usual news from the front-line machines in the high energy physics Laboratories and reports on progress with the latest technologies

  16. The CERN Accelerator School

    CERN Multimedia

    2016-01-01

      Introduction to accelerator physics This course will take place in Istanbul, Turkey, from 18 to 30 September 2016. It is now open for registration, and further information can be found here: http://cas.web.cern.ch/cas/Turkey-2016/Turkey-advert.html

  17. Accelerator for amplification of energy

    International Nuclear Information System (INIS)

    Mori, Yoshiharu

    1998-01-01

    As a forming method of new nuclear energy, an energy amplification system using accelerator driven subcritical reactor is focussed. In order to realize amplification of energy driven by accelerator, development of an accelerator with excellent electric power efficiency is one of the most important problems. The necessary beam power of accelerator is 10 MW, and when reducing used electric power of the accelerator to under 25% of total power generation, more than 30% of electric power efficiency is required for the accelerator. Therefore, an accelerator with excellent electric power efficiency without experiencing before now is required to realize such an aim. A prominent candidate of the accelerator is FFAG (Fixed Field Alternating Gradient) synchrotron (may be called ring synchrotron). In this paper, some simple considerations of electric power efficiency of accelerators and basic parameter of FFAG synchrotron were described. (G.K.)

  18. Relativity and accelerator engineering

    International Nuclear Information System (INIS)

    Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni

    2017-09-01

    From a geometrical viewpoint, according to the theory of relativity, space and time constitute a four-dimensional continuum with pseudo-Euclidean structure. This has recently begun to be a practically important statement in accelerator physics. An X-ray Free Electron Laser (XFEL) is in fact the best, exciting example of an engineering system where improvements in accelerator technology makes it possible to develop ultrarelativistic macroscopic objects with an internal fine structure, and the theory of relativity plays an essential role in their description. An ultrarelativistic electron bunch modulated at nanometer-scale in XFELs has indeed a macroscopic finite-size of order of 10 μm. Its internal, collective structure is characterized in terms of a wave number vector. Here we will show that a four-dimensional geometrical approach, unusual in accelerator physics, is needed to solve problems involving the emission of radiation from an ultrarelativistic modulated electron beam accelerating along a curved trajectory. We will see that relativistic kinematics enters XFEL physics in a most fundamental way through the so-called Wigner rotation of the modulation wave number vector, which is closely associated to the relativity of simultaneity. If not taken into account, relativistic kinematics effects would lead to a strong qualitative disagreement between theory and experiments. In this paper, several examples of relativistic kinematics effects, which are important for current and future XFEL operation, are studied. The theory of relativity is applied by providing details of the clock synchronization procedure within the laboratory frame. This approach, exploited here but unusual in literature, is rather ''practical'', and should be acceptable to accelerator physicists.

  19. Menopause accelerates biological aging

    Science.gov (United States)

    Levine, Morgan E.; Lu, Ake T.; Chen, Brian H.; Hernandez, Dena G.; Singleton, Andrew B.; Ferrucci, Luigi; Bandinelli, Stefania; Salfati, Elias; Manson, JoAnn E.; Quach, Austin; Kusters, Cynthia D. J.; Kuh, Diana; Wong, Andrew; Teschendorff, Andrew E.; Widschwendter, Martin; Ritz, Beate R.; Absher, Devin; Assimes, Themistocles L.; Horvath, Steve

    2016-01-01

    Although epigenetic processes have been linked to aging and disease in other systems, it is not yet known whether they relate to reproductive aging. Recently, we developed a highly accurate epigenetic biomarker of age (known as the “epigenetic clock”), which is based on DNA methylation levels. Here we carry out an epigenetic clock analysis of blood, saliva, and buccal epithelium using data from four large studies: the Women's Health Initiative (n = 1,864); Invecchiare nel Chianti (n = 200); Parkinson's disease, Environment, and Genes (n = 256); and the United Kingdom Medical Research Council National Survey of Health and Development (n = 790). We find that increased epigenetic age acceleration in blood is significantly associated with earlier menopause (P = 0.00091), bilateral oophorectomy (P = 0.0018), and a longer time since menopause (P = 0.017). Conversely, epigenetic age acceleration in buccal epithelium and saliva do not relate to age at menopause; however, a higher epigenetic age in saliva is exhibited in women who undergo bilateral oophorectomy (P = 0.0079), while a lower epigenetic age in buccal epithelium was found for women who underwent menopausal hormone therapy (P = 0.00078). Using genetic data, we find evidence of coheritability between age at menopause and epigenetic age acceleration in blood. Using Mendelian randomization analysis, we find that two SNPs that are highly associated with age at menopause exhibit a significant association with epigenetic age acceleration. Overall, our Mendelian randomization approach and other lines of evidence suggest that menopause accelerates epigenetic aging of blood, but mechanistic studies will be needed to dissect cause-and-effect relationships further. PMID:27457926

  20. Relativity and accelerator engineering

    Energy Technology Data Exchange (ETDEWEB)

    Geloni, Gianluca [European XFEL GmbH, Schenefeld (Germany); Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2017-09-15

    From a geometrical viewpoint, according to the theory of relativity, space and time constitute a four-dimensional continuum with pseudo-Euclidean structure. This has recently begun to be a practically important statement in accelerator physics. An X-ray Free Electron Laser (XFEL) is in fact the best, exciting example of an engineering system where improvements in accelerator technology makes it possible to develop ultrarelativistic macroscopic objects with an internal fine structure, and the theory of relativity plays an essential role in their description. An ultrarelativistic electron bunch modulated at nanometer-scale in XFELs has indeed a macroscopic finite-size of order of 10 μm. Its internal, collective structure is characterized in terms of a wave number vector. Here we will show that a four-dimensional geometrical approach, unusual in accelerator physics, is needed to solve problems involving the emission of radiation from an ultrarelativistic modulated electron beam accelerating along a curved trajectory. We will see that relativistic kinematics enters XFEL physics in a most fundamental way through the so-called Wigner rotation of the modulation wave number vector, which is closely associated to the relativity of simultaneity. If not taken into account, relativistic kinematics effects would lead to a strong qualitative disagreement between theory and experiments. In this paper, several examples of relativistic kinematics effects, which are important for current and future XFEL operation, are studied. The theory of relativity is applied by providing details of the clock synchronization procedure within the laboratory frame. This approach, exploited here but unusual in literature, is rather ''practical'', and should be acceptable to accelerator physicists.

  1. Nonlinear dynamics in particle accelerators

    CERN Document Server

    Dilão, Rui

    1996-01-01

    This book is an introductory course to accelerator physics at the level of graduate students. It has been written for a large audience which includes users of accelerator facilities, accelerator physicists and engineers, and undergraduates aiming to learn the basic principles of construction, operation and applications of accelerators.The new concepts of dynamical systems developed in the last twenty years give the theoretical setting to analyse the stability of particle beams in accelerator. In this book a common language to both accelerator physics and dynamical systems is integrated and dev

  2. Acceleration of polarized proton beams

    International Nuclear Information System (INIS)

    Roser, T.

    1998-01-01

    The acceleration of polarized beams in circular accelerators is complicated by the numerous depolarizing spin resonances. Using a partial Siberian snake and a rf dipole that ensure stable adiabatic spin motion during acceleration has made it possible to accelerate polarized protons to 25 GeV at the Brookhaven AGS. Full Siberian snakes are being developed for RHIC to make the acceleration of polarized protons to 250 GeV possible. A similar scheme is being studied for the 800 GeV HERA proton accelerator

  3. Ion injector for electrostatic accelerator

    International Nuclear Information System (INIS)

    Novikov, M.T.; Tsygikalo, A.A.

    1980-01-01

    Basing on the analysis of formulae connecting beam parameters at the input and output of an electrostatic accelerator, a design of an ion injector for a charge-exchange accelerator is suggested. The distinguishing injector feature is that it contains a preaccelerator with autofocusing of the beam at its output, which provides better matching of ion source and accelerator operating conditions when preserving the conditions of beam autofocusing in the accelerator. Such an injector is a self-contained instrument. It allows control, within certain limits, of ion optics of inlet lenses of the accelerator and preaccelerator during operation when preserving better matching of ion source operation with the accelerator [ru

  4. Unlimited Relativistic Shock Surfing Acceleration

    International Nuclear Information System (INIS)

    Ucer, D.; Shapiro, V. D.

    2001-01-01

    Nonrelativistic shock surfing acceleration at quasiperpendicular shocks is usually considered to be a preacceleration mechanism for slow pickup ions to initiate diffusive shock acceleration. In shock surfing, the particle accelerates along the shock front under the action of the convective electric field of the plasma flow. However, the particle also gains kinetic energy normal to the shock and eventually escapes downstream. We consider the case when ions are accelerated to relativistic velocities. In this case, the ions are likely to be trapped for infinitely long times, because the energy of bounce oscillations tends to decrease during acceleration. This suggests the possibility of unlimited acceleration by shock surfing

  5. Mass spectrometry with accelerators.

    Science.gov (United States)

    Litherland, A E; Zhao, X-L; Kieser, W E

    2011-01-01

    As one in a series of articles on Canadian contributions to mass spectrometry, this review begins with an outline of the history of accelerator mass spectrometry (AMS), noting roles played by researchers at three Canadian AMS laboratories. After a description of the unique features of AMS, three examples, (14)C, (10)Be, and (129)I are given to illustrate the methods. The capabilities of mass spectrometry have been extended by the addition of atomic isobar selection, molecular isobar attenuation, further ion acceleration, followed by ion detection and ion identification at essentially zero dark current or ion flux. This has been accomplished by exploiting the techniques and accelerators of atomic and nuclear physics. In 1939, the first principles of AMS were established using a cyclotron. In 1977 the selection of isobars in the ion source was established when it was shown that the (14)N(-) ion was very unstable, or extremely difficult to create, making a tandem electrostatic accelerator highly suitable for assisting the mass spectrometric measurement of the rare long-lived radioactive isotope (14)C in the environment. This observation, together with the large attenuation of the molecular isobars (13)CH(-) and (12)CH 2(-) during tandem acceleration and the observed very low background contamination from the ion source, was found to facilitate the mass spectrometry of (14)C to at least a level of (14)C/C ~ 6 × 10(-16), the equivalent of a radiocarbon age of 60,000 years. Tandem Accelerator Mass Spectrometry, or AMS, has now made possible the accurate radiocarbon dating of milligram-sized carbon samples by ion counting as well as dating and tracing with many other long-lived radioactive isotopes such as (10)Be, (26)Al, (36)Cl, and (129)I. The difficulty of obtaining large anion currents with low electron affinities and the difficulties of isobar separation, especially for the heavier mass ions, has prompted the use of molecular anions and the search for alternative

  6. Recent progress in particle accelerators

    International Nuclear Information System (INIS)

    Cole, F.T.; Mills, F.E.

    1988-01-01

    Many accelerators have also been built for medical radiography and therapy. Electron accelerators for this application are available commercially, using the electrons directly or bremsstrahlung photons. Neutrons produced by accelerator beams have also been used for therapy with considerable success, and several proton accelerators built for physics research have been adapted for direct therapy with protons. The first proton accelerator specifically for therapy is now being built. Separate from what might be called conventional accelerator technology, an entirely new field utilizing very highly pulsed power has been developed, and beams of short pulses of thousands or millions of amperes peak current in the MeV energy range are now available. These beams have important applications in high-energy particle acceleration, controlled fusion, industrial treatment of materials, and possibly in food preservation. All of these accelerators make use of external fields of acceleration. There is also vigorous research into new methods of acceleration, in many schemes making use of the intense accelerating fields, generated by laser beams or by plasma states of matter. This research has not as yet made traditional kinds of accelerators outmoded, but many workers hope that early in the next century there will be practical new acceleration methods making use of these very high fields. These developments are discussed in detail

  7. Acceleration of 14C beams in electrostatic accelerators

    International Nuclear Information System (INIS)

    Rowton, L.J.; Tesmer, J.R.

    1981-01-01

    Operational problems in the production and acceleration of 14 C beams for nuclear structure research in Los Alamos National Laboratory's Van de Graaff accelerators are discussed. Methods for the control of contamination in ion sources, accelerators and personnel are described. Sputter source target fabrication techniques and the relative beam production efficiencies of various types of bound particulate carbon sputter source targets are presented

  8. Laser beam accelerator

    International Nuclear Information System (INIS)

    Tajima, T.; Dawson, J.M.

    1981-01-01

    Parallel intense photon (laser, microwave, etc.) beams /omega/sub //0, k/sub 0/ and /omega/sub //1, k/sub 1/ shone on a plasma with frequency separation equal to the plasma frequency /omega/sub //p is capable of accelerating plasma electrons to high energies in large flux. The photon beat excites through the forward Raman scattering large amplitude plasmons whose phase velocity is equal to (/omega/ /sub 0/-/omega/sub //1)/(k/sub 0/-k/sub 1/), close to c in an underdense plasma. The multiple forward Raman instability produces smaller and smaller frequency and group velocity of photons; thus the photons slow down in the plasma by emitting accelerated electrons (inverse Cherenkov process). 6 refs

  9. Commissioning the GTA accelerator

    International Nuclear Information System (INIS)

    Sander, O.R.; Atkins, W.H.; Bolme, G.O.; Bowling, S.; Brown, S.; Cole, R.; Gilpatrick, J.D.; Garnett, R.; Guy, F.W.; Ingalls, W.B.; Johnson, K.F.; Kerstiens, D.; Little, C.; Lohsen, R.A.; Lloyd, S.; Lysenko, W.P.; Mottershead, C.T.; Neuschaefer, G.; Power, J.; Rusthoi, D.P.; Sandoval, D.P.; Stevens, R.R.; Vaughn, G.; Wadlinger, E.A.; Connolly, R.; Weiss, R.; Saadatmand, K.

    1992-01-01

    The Ground Test Accelerator (GTA) is being used to resolve the physics and engineering issues related to accelerating, focusing, and steering a high-brightness, high-current H - beam and then neutralizing it. The goal is to produce a 24 MeV, 50 mA device with a 2% duty factor. Specific features of the GTA -- injector, beam optics, rf linac structures, diagnostics, control and rf power systems are described. The first four steps in commissioning have been completed. The RFQ predicted and measured performances are in good agreement; however, the transmission is lower than specifications. Input emittance is larger than design specifications and increases the effects of image charge and multipoles. Displacement of steering magnets in either the horizontal or vertical plane caused beam displacements in both planes. It is suspected that quadrupole rotation is the cause of the coupled motion. 9 figs., 5 tabs., 11 refs

  10. Commissioning the GTA accelerator

    International Nuclear Information System (INIS)

    Sander, O.R.; Atkins, W.H.; Bolme, G.O.; Bowling, S.; Brown, S.; Cole, R.; Gilpatrick, J.D.; Garnett, R.; Guy, F.W.; Ingalls, W.B.; Johnson, K.F.; Kerstiens, D.; Little, C.; Lohsen, R.A.; Lloyd, S.; Lysenko, W.P.; Mottershead, C.T.; Neuschaefer, G.; Power, J.; Rusthoi, D.P.; Sandoval, D.P. Stevens, R.R. Jr.; Vaughn, G.; Wadlinger, E.A.; Yuan, V.; Connolly, R.; Weiss, R.; Saadatmand, K.

    1992-01-01

    The Ground Test Accelerator (GTA) is supported by the Strategic Defense command as part of their Neutral Particle Beam (NPB) program. Neutral particles have the advantage that in space they are unaffected by the earth's magnetic field and travel in straight lines unless they enter the earth's atmosphere and become charged by stripping. Heavy particles are difficult to stop and can probe the interior of space vehicles; hence, NPB can function as a discriminator between warheads and decoys. We are using GTA to resolve the physics and engineering issues related to accelerating, focusing, and steering a high-brightness, high-current H - beam and then neutralizing it. Our immediate goal is to produce a 24-MeV, 50mA device with a 2% duty factor

  11. Accelerators for cancer therapy

    International Nuclear Information System (INIS)

    Lennox, Arlene J.

    2000-01-01

    The vast majority of radiation treatments for cancerous tumors are given using electron linacs that provide both electrons and photons at several energies. Design and construction of these linacs are based on mature technology that is rapidly becoming more and more standardized and sophisticated. The use of hadrons such as neutrons, protons, alphas, or carbon, oxygen and neon ions is relatively new. Accelerators for hadron therapy are far from standardized, but the use of hadron therapy as an alternative to conventional radiation has led to significant improvements and refinements in conventional treatment techniques. This paper presents the rationale for radiation therapy, describes the accelerators used in conventional and hadron therapy, and outlines the issues that must still be resolved in the emerging field of hadron therapy

  12. Review of ion accelerators

    International Nuclear Information System (INIS)

    Alonso, J.

    1990-06-01

    The field of ion acceleration to higher energies has grown rapidly in the last years. Many new facilities as well as substantial upgrades of existing facilities have extended the mass and energy range of available beams. Perhaps more significant for the long-term development of the field has been the expansion in the applications of these beams, and the building of facilities dedicated to areas outside of nuclear physics. This review will cover many of these new developments. Emphasis will be placed on accelerators with final energies above 50 MeV/amu. Facilities such as superconducting cyclotrons and storage rings are adequately covered in other review papers, and so will not be covered here

  13. accelerating cavity from LEP

    CERN Multimedia

    This is an accelerating cavity from LEP, with a layer of niobium on the inside. Operating at 4.2 degrees above absolute zero, the niobium is superconducting and carries an accelerating field of 6 million volts per metre with negligible losses. Each cavity has a surface of 6 m2. The niobium layer is only 1.2 microns thick, ten times thinner than a hair. Such a large area had never been coated to such a high accuracy. A speck of dust could ruin the performance of the whole cavity so the work had to be done in an extremely clean environment. These challenging requirements pushed European industry to new achievements. 256 of these cavities are now used in LEP to double the energy of the particle beams.

  14. Accelerators for cancer therapy

    International Nuclear Information System (INIS)

    Lennox, A.J.

    2000-01-01

    The vast majority of radiation treatments for cancerous tumors are given using electron linacs that provide both electrons and photons at several energies. Design and construction of these linacs are based on mature technology that is rapidly becoming more and more standardized and sophisticated. The use of hadrons such as neutrons, protons, alphas, or carbon, oxygen and neon ions is relatively new. Accelerators for hadron therapy are far from standardized, but the use of hadron therapy as an alternative to conventional radiation has led to significant improvements and refinements in conventional treatment techniques. This paper presents the rationale for radiation therapy, describes the accelerators used in conventional and hadron therapy, and outlines the issues that must still be resolved in the emerging field of hadron therapy. (author)

  15. Particle accelerator physics

    CERN Document Server

    Wiedemann, Helmut

    2015-01-01

    This book by Helmut Wiedemann is a well-established, classic text, providing an in-depth and comprehensive introduction to the field of high-energy particle acceleration and beam dynamics. The present 4th edition has been significantly revised, updated and expanded. The newly conceived Part I is an elementary introduction to the subject matter for undergraduate students. Part II gathers the basic tools in preparation of a more advanced treatment, summarizing the essentials of electrostatics and electrodynamics as well as of particle dynamics in electromagnetic fields. Part III is an extensive primer in beam dynamics, followed, in Part IV, by an introduction and description of the main beam parameters and including a new chapter on beam emittance and lattice design. Part V is devoted to the treatment of perturbations in beam dynamics. Part VI then discusses the details of charged particle acceleration. Parts VII and VIII introduce the more advanced topics of coupled beam dynamics and describe very intense bea...

  16. Accelerators for Cancer Therapy

    Science.gov (United States)

    Lennox, Arlene J.

    2000-05-30

    The vast majority of radiation treatments for cancerous tumors are given using electron linacs that provide both electrons and photons at several energies. Design and construction of these linacs are based on mature technology that is rapidly becoming more and more standardized and sophisticated. The use of hadrons such as neutrons, protons, alphas, or carbon, oxygen and neon ions is relatively new. Accelerators for hadron therapy are far from standardized, but the use of hadron therapy as an alternative to conventional radiation has led to significant improvements and refinements in conventional treatment techniques. This paper presents the rationale for radiation therapy, describes the accelerators used in conventional and hadron therapy, and outlines the issues that must still be resolved in the emerging field of hadron therapy.

  17. Review of ion accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, J.

    1990-06-01

    The field of ion acceleration to higher energies has grown rapidly in the last years. Many new facilities as well as substantial upgrades of existing facilities have extended the mass and energy range of available beams. Perhaps more significant for the long-term development of the field has been the expansion in the applications of these beams, and the building of facilities dedicated to areas outside of nuclear physics. This review will cover many of these new developments. Emphasis will be placed on accelerators with final energies above 50 MeV/amu. Facilities such as superconducting cyclotrons and storage rings are adequately covered in other review papers, and so will not be covered here.

  18. Future accelerators and experiments

    International Nuclear Information System (INIS)

    Richter, B.

    1993-08-01

    This article describes the status of major new accelerator projects and prospects as of mid 1988. It looks at hadron colliders and electron positron colliders. The author looks both at the technology of the machines, and how it will have to be developed for future devices, and the effort required to extract the important physics information from the resulting reaction cascades which are exected to come out of these devices

  19. Future accelerators and experiments

    Energy Technology Data Exchange (ETDEWEB)

    Richter, B.

    1993-08-01

    This article describes the status of major new accelerator projects and prospects as of mid 1988. It looks at hadron colliders and electron positron colliders. The author looks both at the technology of the machines, and how it will have to be developed for future devices, and the effort required to extract the important physics information from the resulting reaction cascades which are exected to come out of these devices.

  20. Particle acceleration by pulsars

    International Nuclear Information System (INIS)

    Arons, Jonathan.

    1980-06-01

    The evidence that pulsars accelerate relativistic particles is reviewed, with emphasis on the γ-ray observations. The current state of knowledge of acceleration in strong waves is summarized, with emphasis on the inability of consistent theories to accelerate very high energy particles without converting too much energy into high energy photons. The state of viable models for pair creation by pulsars is summarized, with the conclusion that pulsars very likely lose rotational energy in winds instead of in superluminous strong waves. The relation of the pair creation models to γ-ray observations and to soft X-ray observations of pulsars is outlined, with the conclusion that energetically viable models may exist, but none have yet yielded useful agreement with the extant data. Some paths for overcoming present problems are discussed. The relation of the favored models to cosmic rays is discussed. It is pointed out that the pairs made by the models may have observable consequences for observation of positrons in the local cosmic ray flux and for observations of the 511 keV line from the interstellar medium. Another new point is that asymmetry of plasma supply from at least one of the models may qualitatively explain the gross asymmetry of the X-ray emission from the Crab nebula. It is also argued that acceleration of cosmic ray nuclei by pulsars, while energetically possible, can occur only at the boundary of the bubbles blown by the pulsars, if the cosmic ray composition is to be anything like that of the known source spectrum

  1. Future Accelerator Magnet Needs

    CERN Document Server

    Devred, Arnaud; Yamamoto, A

    2005-01-01

    Superconducting magnet technology is continually evolving in order to meet the demanding needs of new accelerators and to provide necessary upgrades for existing machines. A variety of designs are now under development, including high fields and gradients, rapid cycling and novel coil configurations. This paper presents a summary of R&D programs in the EU, Japan and the USA. A performance comparison between NbTi and Nb3Sn along with fabrication and cost issues are also discussed.

  2. LEP copper accelerating cavities

    CERN Multimedia

    Laurent Guiraud

    1999-01-01

    These copper cavities were used to generate the radio frequency electric field that was used to accelerate electrons and positrons around the 27-km Large Electron-Positron (LEP) collider at CERN, which ran from 1989 to 2000. The copper cavities were gradually replaced from 1996 with new superconducting cavities allowing the collision energy to rise from 90 GeV to 200 GeV by mid-1999.

  3. Modulational effects in accelerators

    International Nuclear Information System (INIS)

    Satogata, T.

    1997-01-01

    We discuss effects of field modulations in accelerators, specifically those that can be used for operational beam diagnostics and beam halo control. In transverse beam dynamics, combined effects of nonlinear resonances and tune modulations influence diffusion rates with applied tune modulation has been demonstrated. In the longitudinal domain, applied RF phase and voltage modulations provide mechanisms for parasitic halo transport, useful in slow crystal extraction. Experimental experiences with transverse tune and RF modulations are also discussed

  4. Accelerator simulation using computers

    International Nuclear Information System (INIS)

    Lee, M.; Zambre, Y.; Corbett, W.

    1992-01-01

    Every accelerator or storage ring system consists of a charged particle beam propagating through a beam line. Although a number of computer programs exits that simulate the propagation of a beam in a given beam line, only a few provide the capabilities for designing, commissioning and operating the beam line. This paper shows how a ''multi-track'' simulation and analysis code can be used for these applications

  5. Isochronous cyclotrons. Multicharged ion accelerators

    International Nuclear Information System (INIS)

    Shelaev, I.A.

    1976-01-01

    Isochronous cyclotrons for heavy ions are considered. A development of the heavy ion acceleration technique is discussed. The advantages of heavy ion acceleration by means of the isochronous cyclotron in the energy range up to 10 MeV/nucleon are shown. The requirements to an increase of the beam intensity and decrease of the accelerator dimensions are determined. A considerable increase in the beam intensity is achieved in cascade accelerators of heavy ions. Various schemes of such accelerators are considered, and their parameters are given. To obtain the nuclei with energy of 10 GeV/nucleon and higher, some accelerating complexes are projected, e.g. nuclotrons, where the superconducting magnets are supposed to be used. New methods for heavy ion acceleration are worked out, especially, the collective methods of acceleration

  6. Laser-driven electron accelerators

    International Nuclear Information System (INIS)

    Palmer, R.B.

    1981-01-01

    The following possibilities are discussed: inverse free electron laser (wiggler accelerator); inverse Cerenkov effect; plasma accelerator; dielectric tube; and grating linac. Of these, the grating acceleraton is considered the most attractive alternative

  7. The Silicon Lattice Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, J

    2003-11-24

    Previously, the generalized luminosity L was defined and calculated for all incident channels based on an NLC e{sup +}e{sup -} design. Alternatives were then considered to improve the differing beam-beam effects in the e{sup -}e{sup -}, e{gamma} and {gamma}{gamma} channels. One example was tensor beams composed of bunchlets n{sub ijk} implemented with a laser-driven, silicon accelerator based on micromachining techniques. Problems were considered and expressions given for radiative broadening due to bunchlet manipulation near the final focus to optimize luminosity via charge enhancement, neutralization or bunch shaping. Because the results were promising, we explore fully integrated structures that include sources, optics (for both light and particles) and acceleration in a common format--an accelerator-on-chip. Acceptable materials (and wavelengths) must allow velocity synchronism between many laser and electron pulses with optimal efficiency in high radiation environments. There are obvious control and cost advantages that accrue from using silicon structures if radiation effects can be made acceptable and the structures fabricated. Tests related to deep etching, fabrication and radiation effects on candidate amorphous and crystalline materials indicate Si(1.2 < {lambda}{sub L} < 10 {micro}m) and fused c-SiO{sub 2}(0.3 < {lambda}{sub L} < 4 {micro}m) to be ideal.

  8. Particle Accelerator Focus Automation

    Science.gov (United States)

    Lopes, José; Rocha, Jorge; Redondo, Luís; Cruz, João

    2017-08-01

    The Laboratório de Aceleradores e Tecnologias de Radiação (LATR) at the Campus Tecnológico e Nuclear, of Instituto Superior Técnico (IST) has a horizontal electrostatic particle accelerator based on the Van de Graaff machine which is used for research in the area of material characterization. This machine produces alfa (He+) and proton (H+) beams of some μA currents up to 2 MeV/q energies. Beam focusing is obtained using a cylindrical lens of the Einzel type, assembled near the high voltage terminal. This paper describes the developed system that automatically focuses the ion beam, using a personal computer running the LabVIEW software, a multifunction input/output board and signal conditioning circuits. The focusing procedure consists of a scanning method to find the lens bias voltage which maximizes the beam current measured on a beam stopper target, which is used as feedback for the scanning cycle. This system, as part of a wider start up and shut down automation system built for this particle accelerator, brings great advantages to the operation of the accelerator by turning it faster and easier to operate, requiring less human presence, and adding the possibility of total remote control in safe conditions.

  9. Collective focusing ion accelerator

    International Nuclear Information System (INIS)

    Goldin, F.J.

    1986-01-01

    The principal subject of this dissertation is the trapping confinement of pure electron plasmas in bumpy toroidal magnetic fields, with particular attention given to the trapping procedure and the behavior of the plasma during the final equilibrium. The most important aspects of the equilibrium studied were the qualitative nature of the plasma configuration and motion and its density, distribution and stability. The motivation for this study was that an unneutralized cloud of electrons contained in a toroidal system, sufficiently dense and stable, may serve to electrostatically focus ions (against centrifugal and self space charge forces) in a cyclic ion accelerator. Such an accelerator, known as a Collective Focusing Ion Accelerator (CFIA) could be far smaller than conventional designs (which use external magnetic fields directly to focus the ions) due to the smaller gyro-radium of an electron in a magnetic field of given strength. The electron cloud generally drifted poloidally at a finite radius from the toroidal minor axis. As this would preclude focusing ions with such clouds, damping this motion was investigated. Finite resistance in the normally perfectly conductive vessel wall did this. In further preparation for a working CFIA, additional experiments studied the effect of ions on the stability of the electron cloud

  10. [Accelerated orthodontic treatment].

    Science.gov (United States)

    Liem, A M L; Hoogeveen, E J; Jansma, J; Ren, Y

    2015-11-01

    An orthodontic treatment usually involves a long process which often represents an obstacle for patients. To overcome this problem, surgical techniques have been developed to support and accelerate the orthodontic treatment. Two systematic reviews of the literature on clinical research and animal experiments were carried out in order to draw reliable conclusions about the effectiveness of the various surgical techniques. A total of 18 clinical studies and 22 animal experimental studies were analysed. In both reviews of the literature, a study was made of whether the surgical techniques resulted in an accelerated rate of tooth movement and which complications may be observed. In addition, which biological mechanisms take place during surgically facilitated orthodontics was investigated. Both reviews reported accelerated tooth movement with minimal complications after surgical procedures in comparison to conventional orthodontics. An increase in catabolic and anabolic activities was observed. It has to be concluded that based on the quality of the current literature there is still insufficient information for general conclusions and that more standardised prospective research is necessary for a reliable conclusion about the optimal method of treatment.

  11. Accelerator mass spectrometry.

    Science.gov (United States)

    Hellborg, Ragnar; Skog, Göran

    2008-01-01

    In this overview the technique of accelerator mass spectrometry (AMS) and its use are described. AMS is a highly sensitive method of counting atoms. It is used to detect very low concentrations of natural isotopic abundances (typically in the range between 10(-12) and 10(-16)) of both radionuclides and stable nuclides. The main advantages of AMS compared to conventional radiometric methods are the use of smaller samples (mg and even sub-mg size) and shorter measuring times (less than 1 hr). The equipment used for AMS is almost exclusively based on the electrostatic tandem accelerator, although some of the newest systems are based on a slightly different principle. Dedicated accelerators as well as older "nuclear physics machines" can be found in the 80 or so AMS laboratories in existence today. The most widely used isotope studied with AMS is 14C. Besides radiocarbon dating this isotope is used in climate studies, biomedicine applications and many other fields. More than 100,000 14C samples are measured per year. Other isotopes studied include 10Be, 26Al, 36Cl, 41Ca, 59Ni, 129I, U, and Pu. Although these measurements are important, the number of samples of these other isotopes measured each year is estimated to be less than 10% of the number of 14C samples. Copyright 2008 Wiley Periodicals, Inc.

  12. The tandem betatron accelerator

    International Nuclear Information System (INIS)

    Keinigs, R.

    1991-01-01

    This paper reports that the tandem betatron is a compact, high-current induction accelerator that has the capability to accelerate electrons to an energy of order one gigavolt. Based upon the operating principle of a conventional betatron, the tandem betatron employs two synchronized induction cores operating 180 degrees out of phase. Embedded within the cores are the vacuum chambers, and these are connected by linear transport sections to allow for moving the beam back and forth between the two betatrons. The 180 degree phase shift between the core fluxes permits the circumvention of the flux swing constraint that limits the maximum energy gain of a conventional betatron. By transporting the beam between the synchronized cores, an electron can access more than one acceleration cycle, and thereby continue to gain energy. This added degree of freedom also permits a significant decrease in the size of the magnet system. Biasing coils provide independent control of the confining magnetic field. Provided that efficient beam switching can be performed, it appears feasible that a one gigavolt electron beam can be generated and confined. At this energy, a high current electron beam circulating in a one meter radius orbit could provide a very intense source of short wavelength (λ < 10 nm) synchrotron radiation. This has direct application to the emerging field of x-ray lithography. At more modest energies (10 MeV-30 MEV) a compact tandem betatron could be employed in the fields of medical radiation therapy, industrial radiography, and materials processing

  13. Electrostatic Plasma Accelerator (EPA)

    Science.gov (United States)

    Brophy, John R.; Aston, Graeme

    1995-01-01

    The application of electric propulsion to communications satellites, however, has been limited to the use of hydrazine thrusters with electric heaters for thrust and specific impulse augmentation. These electrothermal thrusters operate at specific impulse levels of approximately 300 s with heater powers of about 500 W. Low power arcjets (1-3 kW) are currently being investigated as a way to increase specific impulse levels to approximately 500 s. Ion propulsion systems can easily produce specific impulses of 3000 s or greater, but have yet to be applied to communications satellites. The reasons most often given for not using ion propulsion systems are their high level of overall complexity, low thrust with long burn times, and the difficulty of integrating the propulsion system into existing commercial spacecraft busses. The Electrostatic Plasma Accelerator (EPA) is a thruster concept which promises specific impulse levels between low power arcjets and those of the ion engine while retaining the relative simplicity of the arcjet. The EPA thruster produces thrust through the electrostatic acceleration of a moderately dense plasma. No accelerating electrodes are used and the specific impulse is a direct function of the applied discharge voltage and the propellant atomic mass.

  14. Particle Accelerator Focus Automation

    Directory of Open Access Journals (Sweden)

    Lopes José

    2017-08-01

    Full Text Available The Laboratório de Aceleradores e Tecnologias de Radiação (LATR at the Campus Tecnológico e Nuclear, of Instituto Superior Técnico (IST has a horizontal electrostatic particle accelerator based on the Van de Graaff machine which is used for research in the area of material characterization. This machine produces alfa (He+ and proton (H+ beams of some μA currents up to 2 MeV/q energies. Beam focusing is obtained using a cylindrical lens of the Einzel type, assembled near the high voltage terminal. This paper describes the developed system that automatically focuses the ion beam, using a personal computer running the LabVIEW software, a multifunction input/output board and signal conditioning circuits. The focusing procedure consists of a scanning method to find the lens bias voltage which maximizes the beam current measured on a beam stopper target, which is used as feedback for the scanning cycle. This system, as part of a wider start up and shut down automation system built for this particle accelerator, brings great advantages to the operation of the accelerator by turning it faster and easier to operate, requiring less human presence, and adding the possibility of total remote control in safe conditions.

  15. Accelerated Profile HMM Searches.

    Directory of Open Access Journals (Sweden)

    Sean R Eddy

    2011-10-01

    Full Text Available Profile hidden Markov models (profile HMMs and probabilistic inference methods have made important contributions to the theory of sequence database homology search. However, practical use of profile HMM methods has been hindered by the computational expense of existing software implementations. Here I describe an acceleration heuristic for profile HMMs, the "multiple segment Viterbi" (MSV algorithm. The MSV algorithm computes an optimal sum of multiple ungapped local alignment segments using a striped vector-parallel approach previously described for fast Smith/Waterman alignment. MSV scores follow the same statistical distribution as gapped optimal local alignment scores, allowing rapid evaluation of significance of an MSV score and thus facilitating its use as a heuristic filter. I also describe a 20-fold acceleration of the standard profile HMM Forward/Backward algorithms using a method I call "sparse rescaling". These methods are assembled in a pipeline in which high-scoring MSV hits are passed on for reanalysis with the full HMM Forward/Backward algorithm. This accelerated pipeline is implemented in the freely available HMMER3 software package. Performance benchmarks show that the use of the heuristic MSV filter sacrifices negligible sensitivity compared to unaccelerated profile HMM searches. HMMER3 is substantially more sensitive and 100- to 1000-fold faster than HMMER2. HMMER3 is now about as fast as BLAST for protein searches.

  16. Optimizing accelerator technology

    CERN Multimedia

    Katarina Anthony

    2012-01-01

    A new EU-funded research and training network, oPAC, is bringing together 22 universities, research centres and industry partners to optimize particle accelerator technology. CERN is one of the network’s main partners and will host 5 early-stage researchers in the BE department.   A diamond detector that will be used for novel beam diagnostics applications in the oPAC project based at CIVIDEC. (Image courtesy of CIVIDEC.) As one of the largest Marie Curie Initial Training Networks ever funded by the EU – to the tune of €6 million – oPAC extends well beyond the particle physics community. “Accelerator physics has become integral to research in almost every scientific discipline – be it biology and life science, medicine, geology and material science, or fundamental physics,” explains Carsten P. Welsch, oPAC co-ordinator based at the University of Liverpool. “By optimizing the operation of accelerators, all of these...

  17. Introduction to Microwave Linear [Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Whittum, David H

    1999-01-04

    The elements of microwave linear accelerators are introduced starting with the principles of acceleration and accelerating structures. Considerations for microwave structure modeling and design are developed from an elementary point of view. Basic elements of microwave electronics are described for application to the accelerator circuit and instrumentation. Concepts of beam physics are explored together with examples of common beamline instruments. Charged particle optics and lattice diagnostics are introduced. Considerations for fixed-target and colliding-beam experimentation are summarized.

  18. Electron accelerators for environmental protection

    International Nuclear Information System (INIS)

    Zimek, Z.

    1998-01-01

    The primary objective of this publication is to provide information suitable for electron accelerators implementation in facilities applying radiation technology for environmental protection. It should be noticed that radiation processing has been successfully used in the fields of crosslinking polymer curing and medical products sterilization for more than 40 years. Practical application of radiation technology today extends on SO 2 and NO x removal from the flue gas (one of major power intensive radiation processing), destruction and removal of organic chemicals from water, decreasing bacteria content in the irradiated sludge and waste water. On the other hand the increased awareness of environmental pollution hazards and more stringent waste regulations in many countries may open stronger support for environmentally oriented technologies. This publication provides an evaluation of electron accelerators capabilities in respect of environmental applications where technological and economical criteria are now well defined. In order to determine the potential of electron accelerators, the literature data were examined as well visits and meetings with various accelerator manufacturers were performed by the author. Experience of the author in accelerator facilities construction and exploitation including those which were used for environmental protection are significant part of this publication. The principle of accelerator action was described in Chapter 1. Early development, accelerator classification and fields of accelerators application were included to this chapter as well. Details of accelerator construction was described in Chapter 2 to illustrate physical capability of accelerators to perform the function of ionizing radiation source. Electron beam extraction devices, under beam equipment, electron beam parameters and measuring methods were characterized in this chapter as well. Present studies of accelerator technology was described in Chapter 3, where

  19. Overview of accelerators in medicine

    International Nuclear Information System (INIS)

    Lennox, A.J.

    1993-06-01

    Accelerators used for medicine include synchrotrons, cyclotrons, betatrons, microtrons, and electron, proton, and light ion linacs. Some accelerators which were formerly found only at physics laboratories are now being considered for use in hospital-based treatment and diagnostic facilities. This paper presents typical operating parameters for medical accelerators and gives specific examples of clinical applications for each type of accelerator, with emphasis on recent developments in the field

  20. Science and Technology of Accelerators

    International Nuclear Information System (INIS)

    Valerio Lizarraga, Cristhian; Duarte, Carlos; Castilla Loaeza, Alejandro; Chavez Valenzuela, Daniel; Chahín, Karim Hernández; Cuna, Humberto Maury; Medina Medrano, Luis; Valdivia García, Alan; Cantón, Gerardo Guillermo; Reyes Herrera, Juan; Güitrón, Salvador Sosa; Yee Rendón, Bruce

    2016-01-01

    The Mexican Particle Accelerator Community (CMAP) was created in 2015 and currently its members participate in different experiments around the world. Using their expertise, they are working in the development of the particle accelerators area in Mexico. This paper provides a summary of the research done by its members and presents the preliminary design of an electron linear particle accelerator (eLINAC). This proposal will be the first accelerator designed and created in Mexico. (paper)

  1. Modern accelerators in ancient Rome

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    For the first time, the achievements and hopes of the broad European accelerator community were brought together in a European Particle Accelerator Conference, held in Rome in June. Ranging from the vast machines at CERN to the small medical accelerators operating in thousands of hospitals, the programme underlined how modern civilization has benefited from the ability to handle charged particle beams

  2. ACCELERATORS: Nonlinear dynamics in Sardinia

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    In the last few years, two schools devoted to accelerator physics have been set up, one on either side of the Atlantic. The US School on High Energy Particle Accelerators has organized Summer Schools on the physics of particle accelerators, hosted by the major American Laboratories, each year since 1981

  3. New techniques for particle accelerators

    International Nuclear Information System (INIS)

    Sessler, A.M.

    1990-06-01

    A review is presented of the new techniques which have been proposed for use in particle accelerators. Attention is focused upon those areas where significant progress has been made in the last two years--in particular, upon two-beam accelerators, wakefield accelerators, and plasma focusers. 26 refs., 5 figs., 1 tab

  4. Theoretical problems in accelerator physics

    International Nuclear Information System (INIS)

    1992-01-01

    This report discusses the following research on accelerators: computational methods; higher order mode suppression in accelerators structures; overmoded waveguide components and application to SLED II and power transport; rf sources; accelerator cavity design for a B factory asymmetric collider; and photonic band gap cavities

  5. High intensity circular proton accelerators

    International Nuclear Information System (INIS)

    Craddock, M.K.

    1987-12-01

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

  6. Stochastic acceleration by hydromagnetic turbulence

    International Nuclear Information System (INIS)

    Kulsrud, R.M.

    1979-03-01

    A general theory for particle acceleration by weak hydromagnetic turbulence with a given spectrum of waves is described. Various limiting cases, corresponding to Fermi acceleration and magnetic pumping, are discussed and two numerical examples illustrating them are given. An attempt is made to show that the expression for the rate of Fermi acceleration is valid for finite amplitudes

  7. Particle acceleration by collective effects

    International Nuclear Information System (INIS)

    Keefe, D.

    1976-01-01

    Successful acceleration of protons and other ions has been achieved experimentally in this decade by a number of different collective methods. The attainment of very high accelerating fields has been established although so far the acceleration distance has been confined to only a few centimeters. Efforts are in progress to understand the accelerating mechanisms in detail and, as a result, to devise ways of extending considerably the acceleration distance. This paper is intended to review the current progress, expectations, and limitations of the different approaches. (author)

  8. APT accelerator. Topical report

    International Nuclear Information System (INIS)

    Lawrence, G.; Rusthoi, D.

    1995-03-01

    The Accelerator Production of Tritium (APT) project, sponsored by Department of Energy Defense Programs (DOE/DP), involves the preconceptual design of an accelerator system to produce tritium for the nation's stockpile of nuclear weapons. Tritium is an isotope of hydrogen used in nuclear weapons, and must be replenished because of radioactive decay (its half-life is approximately 12 years). Because the annual production requirements for tritium has greatly decreased since the end of the Cold War, an alternative approach to reactors for tritium production, based on a linear accelerator, is now being seriously considered. The annual tritium requirement at the time this study was undertaken (1992-1993) was 3/8 that of the 1988 goal, usually stated as 3/8-Goal. Continued reduction in the number of weapons in the stockpile has led to a revised (lower) production requirement today (March, 1995). The production requirement needed to maintain the reduced stockpile, as stated in the recent Nuclear Posture Review (summer 1994) is approximately 3/16-Goal, half the previous level. The Nuclear Posture Review also requires that the production plant be designed to accomodate a production increase (surge) to 3/8-Goal capability within five years, to allow recovery from a possible extended outage of the tritium plant. A multi-laboratory team, collaborating with several industrial partners, has developed a preconceptual APT design for the 3/8-Goal, operating at 75% capacity. The team has presented APT as a promising alternative to the reactor concepts proposed for Complex-21. Given the requirements of a reduced weapons stockpile, APT offers both significant safety, environmental, and production-fexibility advantages in comparison with reactor systems, and the prospect of successful development in time to meet the US defense requirements of the 21st Century

  9. VLHC accelerator physics

    Energy Technology Data Exchange (ETDEWEB)

    Michael Blaskiewicz et al.

    2001-11-01

    A six-month design study for a future high energy hadron collider was initiated by the Fermilab director in October 2000. The request was to study a staged approach where a large circumference tunnel is built that initially would house a low field ({approx}2 T) collider with center-of-mass energy greater than 30 TeV and a peak (initial) luminosity of 10{sup 34} cm{sup -2}s{sup -1}. The tunnel was to be scoped, however, to support a future upgrade to a center-of-mass energy greater than 150 TeV with a peak luminosity of 2 x 10{sup 34} cm{sup -2} sec{sup -1} using high field ({approx} 10 T) superconducting magnet technology. In a collaboration with Brookhaven National Laboratory and Lawrence Berkeley National Laboratory, a report of the Design Study was produced by Fermilab in June 2001. 1 The Design Study focused on a Stage 1, 20 x 20 TeV collider using a 2-in-1 transmission line magnet and leads to a Stage 2, 87.5 x 87.5 TeV collider using 10 T Nb{sub 3}Sn magnet technology. The article that follows is a compilation of accelerator physics designs and computational results which contributed to the Design Study. Many of the parameters found in this report evolved during the study, and thus slight differences between this text and the Design Study report can be found. The present text, however, presents the major accelerator physics issues of the Very Large Hadron Collider as examined by the Design Study collaboration and provides a basis for discussion and further studies of VLHC accelerator parameters and design philosophies.

  10. APT accelerator. Topical report

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence, G.; Rusthoi, D. [comp.] [ed.

    1995-03-01

    The Accelerator Production of Tritium (APT) project, sponsored by Department of Energy Defense Programs (DOE/DP), involves the preconceptual design of an accelerator system to produce tritium for the nation`s stockpile of nuclear weapons. Tritium is an isotope of hydrogen used in nuclear weapons, and must be replenished because of radioactive decay (its half-life is approximately 12 years). Because the annual production requirements for tritium has greatly decreased since the end of the Cold War, an alternative approach to reactors for tritium production, based on a linear accelerator, is now being seriously considered. The annual tritium requirement at the time this study was undertaken (1992-1993) was 3/8 that of the 1988 goal, usually stated as 3/8-Goal. Continued reduction in the number of weapons in the stockpile has led to a revised (lower) production requirement today (March, 1995). The production requirement needed to maintain the reduced stockpile, as stated in the recent Nuclear Posture Review (summer 1994) is approximately 3/16-Goal, half the previous level. The Nuclear Posture Review also requires that the production plant be designed to accomodate a production increase (surge) to 3/8-Goal capability within five years, to allow recovery from a possible extended outage of the tritium plant. A multi-laboratory team, collaborating with several industrial partners, has developed a preconceptual APT design for the 3/8-Goal, operating at 75% capacity. The team has presented APT as a promising alternative to the reactor concepts proposed for Complex-21. Given the requirements of a reduced weapons stockpile, APT offers both significant safety, environmental, and production-fexibility advantages in comparison with reactor systems, and the prospect of successful development in time to meet the US defense requirements of the 21st Century.

  11. Accelerated Innovation Pilot

    Science.gov (United States)

    Davis, Jeffrey

    2012-01-01

    Opportunities: I. Engage NASA team (examples) a) Research and technology calls . provide suggestions to AES, HRP, OCT. b) Use NASA@Work to solicit other ideas; (possibly before R+D calls). II. Stimulate collaboration (examples) a) NHHPC. b) Wharton Mack Center for Technological Innovation (Feb 2013). c) International ] DLR ] :envihab (July 2013). d) Accelerated research models . NSF, Myelin Repair Foundation. III. Engage public Prizes (open platform: InnoCentive, yet2.com, NTL; Rice Business Plan, etc.) IV. Use same methods to engage STEM.

  12. Accelerating abelian gauge dynamics

    CERN Document Server

    Adler, Stephen Louis

    1991-01-01

    In this paper, we suggest a new acceleration method for Abelian gauge theories based on linear transformations to variables which weight all length scales equally. We measure the autocorrelation time for the Polyakov loop and the plaquette at β=1.0 in the U(1) gauge theory in four dimensions, for the new method and for standard Metropolis updates. We find a dramatic improvement for the new method over the Metropolis method. Computing the critical exponent z for the new method remains an important open issue.

  13. Cosmic Accelerators: An Introduction

    International Nuclear Information System (INIS)

    Kanbach, Gottfried

    2005-01-01

    High energy, relativistic, particles are an essential component of the Universe and play a major role in astrophysics. In a few years we will reach the centennial of the discovery of cosmic rays; all through this century the properties, origin, and effects of this radiation have intrigued researchers in astrophysics and elementary particles alike. We briefly review the history, current status, and future perspectives of cosmic ray research. Emphasis will be placed on the multitude of cosmic accelerators, direct observations of these objects, and the effects of cosmic rays in the Galaxy and beyond

  14. ACCELERATING NANO-TECHNOLOGICAL

    DEFF Research Database (Denmark)

    Jensen, Jens Stissing; Koch, Christian

    2007-01-01

    By viewing the construction industry as a technological innovation system (TIS) this paper discusses possible initiatives to accelerate nanotechnological innovations. The point of departure is a recent report on the application of nano-technology in the Danish construction industry, which concludes...... of the system are furthermore poorly equipped at identifying potentials within high-tech areas. In order to exploit the potentials of nano-technology it is thus argued that an alternative TIS needs to be established. Initiatives should identify and support “incubation rooms” or marked niches in order...

  15. Medical applications of accelerators

    CERN Document Server

    Rossi, Sandro

    1998-01-01

    At Present, about five thousands accelerators are devoted to biomedical applications. They are mainly used in radiotherapy, research and medical radioisotopes production. In this framework oncological hadron-therapy deserves particular attention since it represents a field in rapid evolution thanks to the joint efforts of laboratories with long experiences in particle physics. It is the case of CERN where the design of an optimised synchrotron for medical applications has been pursued. These lectures present these activities with particular attention to the new developments which are scientifically interesting and/or economically promising.

  16. Broadband accelerator control network

    International Nuclear Information System (INIS)

    Skelly, J.; Clifford, T.; Frankel, R.

    1983-01-01

    A broadband data communications network has been implemented at BNL for control of the Alternating Gradient Synchrotron (AG) proton accelerator, using commercial CATV hardware, dual coaxial cables as the communications medium, and spanning 2.0 km. A 4 MHz bandwidth Digital Control channel using CSMA-CA protocol is provided for digital data transmission, with 8 access nodes available over the length of the RELWAY. Each node consists of an rf modem and a microprocessor-based store-and-forward message handler which interfaces the RELWAY to a branch line implemented in GPIB. A gateway to the RELWAY control channel for the (preexisting) AGS Computerized Accelerator Operating system has been constructed using an LSI-11/23 microprocessor as a device in a GPIB branch line. A multilayer communications protocol has been defined for the Digital Control Channel, based on the ISO Open Systems Interconnect layered model, and a RELWAY Device Language defined as the required universal language for device control on this channel

  17. Washington Accelerator Conference

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    Highlights of the 1993 Particle Accelerator Conference, held in Washington in May, were picked out in the previous issue (page 18). Talks on the big hadron colliders reflected the sea-change in the accelerator world where the scale, complexity and cost of the front-line projects has slowed the pace of developments (not unlike the scene in particle physics itself). Speaking before the anti-SSC vote in the House of Representatives in June, Dick Briggs reviewed the situation at the SSC Superconducting Supercollider in Ellis County, Texas. The linac building is near completion and the Low Energy Booster will be ready to receive components early next year. Tunnelling for the Main Ring is advancing rapidly with four boring machines in action. Five miles of tunnel have been completed since January and the pace has now stepped up to nearly a mile each week. The superconducting magnet news is good. Following the successful initial string test of a half cell of the magnet lattice, a two-ring full cell with all associated services is being assembled. The mechanical robustness of the magnet design was confirmed when a dipole was taken to 9.7 T when cooled to 1.8 K. In the Magnet Test Lab itself, ten test stands are installed and equipped

  18. Accelerator School Success

    CERN Multimedia

    2004-01-01

    Accelerator specialists don't grow on trees: training them is the job of the CERN Accelerator School (CAS). Group photo during visit to the Daresbury Laboratory. CAS and the CCLRC Daresbury Laboratory jointly organised a specialised school on Power Converters in Warrington, England from 12-18 May 2004. The last CAS Power Converter course was in 1990, so there was plenty of ground to cover. The challenging programme proposed a review of the state of the art and the latest developments in the field, including 30 hours of tuition. The school also included a visit to the CCLRC Daresbury laboratory, a one-day excursion to Liverpool and Chester and a themed (Welsh medieval) dinner at the school's closure. A record attendance of 91 students of more than 20 different nationalities included not only participants from Europe and North America but also from Armenia, Taiwan, India, Turkey, Iran and for the first time, fee-paying students from China and Australia. European industry showed a welcome and solid interest in...

  19. Chicago particle accelerator conference

    International Nuclear Information System (INIS)

    Southworth, Brian

    1989-01-01

    Naturally, emphasis at the Particle Accelerator Conference in Chicago in March was on work in the US, just as the newly instituted European Particle Accelerator Conference places emphasis on work in the 'old continent'. All will come together at the international conference in Japan in August. The proposed US Superconducting Supercollider (SSC) was highlighted in the opening talk at Chicago. Progress on this inchoate project to explore the TeV (1000 GeV) energy region by colliding 20 TeV proton beams was reported by the recently-appointed Director of the SSC Laboratory, Roy Schwitters. He reviewed the physics challenges and described progress and plans towards full authorization of construction.This year, the SSC conceptual design will be transformed into a 'site specific' report, now that the location at Waxahachie in Ellis County, Texas, has been selected. The Central Design Group, based in Berkeley for the past few years, will soon move to the Waxahachie region. The top management structure is taking shape and an International Advisory Committee is being formed

  20. Linear particle accelerator

    International Nuclear Information System (INIS)

    Richards, J.A.

    1977-01-01

    A linear particle accelerator which provides a pulsed beam of charged particles of uniform energy is described. The accelerator is in the form of an evacuated dielectric tube, inside of which a particle source is located at one end of the tube, with a target or window located at the other end of the dielectric tube. Along the length of the tube are externally located pairs of metal plates, each insulated from each other in an insulated housing. Each of the plates of a pair are connected to an electrical source of voltage of opposed polarity, with the polarity of the voltage of the plates oriented so that the plate of a pair, nearer to the particle source, is of the opposed polarity to the charge of the particle emitted by the source. Thus, a first plate about the tube located nearest the particle source, attracts a particle which as it passes through the tube past the first plate is then repelled by the reverse polarity of the second plate of the pair to continue moving towards the target

  1. Accelerator Technology: Geodesy and Alignment for Particle Accelerators

    CERN Document Server

    Missiaen, D

    2013-01-01

    This document is part of Subvolume C 'Accelerators and Colliders' of Volume 21 'Elementary Particles' of Landolt-Börnstein - Group I 'Elementary Particles, Nuclei and Atoms'. It contains the the Section '8.9 Geodesy and Alignment for Particle Accelerators' of the Chapter '8 Accelerator Technology' with the content: 8.9 Geodesy and Alignment for Particle Accelerators 8.9.1 Introduction 8.9.2 Reference and Co-ordinate Systems 8.9.3 Definition of the Beam Line on the Accelerator Site 8.9.4 Geodetic Network 8.9.5 Tunnel Preliminary Works 8.9.6 The Alignment References 8.9.7 Alignment of Accelerator Components 8.9.8 Permanent Monitoring and Remote Alignment of Low Beta Quadrupoles 8.9.9 Alignment of Detector Components

  2. 2014 Joint International Accelerator School: Beam Loss and Accelerator Protection

    CERN Document Server

    JAS - Joint US-CERN-Japan-Russia Accelerator School

    2016-01-01

    Many particle accelerators operate with very high beam power and very high energy stored in particle beams as well as in magnet systems. In the future, the beam power in high intensity accelerators will further increase. The protection of the accelerator equipment from the consequences of uncontrolled release of the energy is essential. This was the motivation for organizing a first school on beam losses and accelerator protection (in general referred to as machine protection). During the school the methods and technologies to identify, mitigate, monitor and manage the technical risks associated with the operation of accelerators with high-power beams or subsystems with large stored energy were presented. At the completion of the school the participants should have been able to understand the physical phenomena that can damage machine subsystems or interrupt operations and to analyze an accelerator facility to produce a register of technical risks and the corresponding risk mitigation and management strategie...

  3. CERN Accelerator School: Registration open for Advanced Accelerator Physics course

    CERN Multimedia

    2015-01-01

    Registration is now open for the CERN Accelerator School’s Advanced Accelerator Physics course to be held in Warsaw, Poland from 27 September to 9 October 2015.   The course will be of interest to physicists and engineers who wish to extend their knowledge of accelerator physics. The programme offers core lectures on accelerator physics in the mornings and a practical course with hands-on tuition in the afternoons.  Further information can be found at: http://cas.web.cern.ch/cas/Poland2015/Warsaw-advert.html http://indico.cern.ch/event/361988/

  4. CERN Accelerator School: Registration open for Advanced Accelerator Physics course

    CERN Multimedia

    2015-01-01

    Registration is now open for the CERN Accelerator School’s Advanced Accelerator Physics course to be held in Warsaw, Poland from 27 September to 9 October 2015.   The course will be of interest to physicists and engineers who wish to extend their knowledge of Accelerator Physics. The programme offers core lectures on accelerator physics in the mornings and a practical course with hands-on tuition in the afternoons.  Further information can be found at: http://cas.web.cern.ch/cas/Poland2015/Warsaw-advert.html http://indico.cern.ch/event/361988/

  5. Accelerating tube for the ''EG-1'' electrostatic accelerator

    International Nuclear Information System (INIS)

    Romanov, V.A.; Ivanov, V.V.; Krupnov, E.P.; Debin, V.K.; Dudkin, N.I.; Volodin, V.I.

    1980-01-01

    A design of an accelerating tube (AT) for an electrostatic accelerator of the EG-1 type is described. Primary consideration in the development of the AT has been given to increasing the electric strength of accelerating gaps, the vacuum conductivity and better insulator screening from charged particles. After AT vacuum and high-voltage ageing in the accelerator, a hydrogen ions beam of up to 80 μA has been produced. The beam was adequately shaped in the energy range from 1.8 to 5.0 MeV [ru

  6. Survey of Advanced Acceleration Techniques

    CERN Document Server

    Joshi, C J

    2004-01-01

    In this talk I will review the recent progress on the production, manipulation, transport, acceleration and focusing of relativistic electron beams using advanced techniques. In particular, I will report recent progress on cathode-less electron injectors, IFEL bunchers and accelerators, plasma accelerating and transport structures, and electron and positron beam focusing using plasmas. The plasma structures for acceleration can be excited either by laser beams or charged-particle beams. The acceleration gradients in either case can be enormous. For unmatched beams the betatron radiation loss, as the beam oscillates transversely in the high gradient accelerating structure, can generate a high brightness x-ray beam. These x-rays can, in turn, be used to generate positrons. Work done by different groups around the world will be reviewed.

  7. Advanced Accelerators for Medical Applications

    Science.gov (United States)

    Uesaka, Mitsuru; Koyama, Kazuyoshi

    We review advanced accelerators for medical applications with respect to the following key technologies: (i) higher RF electron linear accelerator (hereafter “linac”); (ii) optimization of alignment for the proton linac, cyclotron and synchrotron; (iii) superconducting magnet; (iv) laser technology. Advanced accelerators for medical applications are categorized into two groups. The first group consists of compact medical linacs with high RF, cyclotrons and synchrotrons downsized by optimization of alignment and superconducting magnets. The second group comprises laser-based acceleration systems aimed of medical applications in the future. Laser plasma electron/ion accelerating systems for cancer therapy and laser dielectric accelerating systems for radiation biology are mentioned. Since the second group has important potential for a compact system, the current status of the established energy and intensity and of the required stability are given.

  8. Tandem electrostatic accelerators for BNCT

    International Nuclear Information System (INIS)

    Ma, J.C.

    1994-01-01

    The development of boron neutron capture therapy (BNCT) into a viable therapeutic modality will depend, in part, on the availability of suitable neutron sources compatible with installation in a hospital environment. Low-energy accelerator-based intense neutron sources, using electrostatic or radio frequency quadrupole proton accelerators have been suggested for this purpose and are underdevelopment at several laboratories. New advances in tandem electrostatic accelerator technology now allow acceleration of the multi-milliampere proton beams required to produce therapeutic neutron fluxes for BNCT. The relatively compact size, low weight and high power efficiency of these machines make them particularly attractive for installation in a clinical or research facility. The authors will describe the limitations on ion beam current and available neutron flux from tandem accelerators relative to the requirements for BNCT research and therapy. Preliminary designs and shielding requirements for a tandern accelerator-based BNCT research facility will also be presented

  9. Electrostatic accelerators fundamentals and applications

    CERN Document Server

    2005-01-01

    Electrostatic accelerators are an important and widespread subgroup within the broad spectrum of modern, large particle acceleration devices. They are specifically designed for applications that require high-quality ion beams in terms of energy stability and emittance at comparatively low energies (a few MeV). Their ability to accelerate virtually any kind of ion over a continuously tunable range of energies make them a highly versatile tool for investigations in many research fields including, but not limited to, atomic and nuclear spectroscopy, heavy ion reactions, accelerator mass spectroscopy as well as ion-beam analysis and modification. The book is divided into three parts. The first part concisely introduces the field of accelerator technology and techniques that emphasize their major modern applications. The second part treats the electrostatic accelerator per se: its construction and operational principles as well as its maintenance. The third part covers all relevant applications in which electrosta...

  10. Linear Accelerator Laboratory

    International Nuclear Information System (INIS)

    1976-01-01

    This report covers the activity of the Linear Accelerator Laboratory during the period June 1974-June 1976. The activity of the Laboratory is essentially centered on high energy physics. The main activities were: experiments performed with the colliding rings (ACO), construction of the new colliding rings and beginning of the work at higher energy (DCI), bubble chamber experiments with the CERN PS neutrino beam, counter experiments with CERN's PS and setting-up of equipment for new experiments with CERN's SPS. During this period a project has also been prepared for an experiment with the new PETRA colliding ring at Hamburg. On the other hand, intense collaboration with the LURE Laboratory, using the electron synchrotron radiation emitted by ACO and DCI, has been developed [fr

  11. Network acceleration techniques

    Science.gov (United States)

    Crowley, Patricia (Inventor); Awrach, James Michael (Inventor); Maccabe, Arthur Barney (Inventor)

    2012-01-01

    Splintered offloading techniques with receive batch processing are described for network acceleration. Such techniques offload specific functionality to a NIC while maintaining the bulk of the protocol processing in the host operating system ("OS"). The resulting protocol implementation allows the application to bypass the protocol processing of the received data. Such can be accomplished this by moving data from the NIC directly to the application through direct memory access ("DMA") and batch processing the receive headers in the host OS when the host OS is interrupted to perform other work. Batch processing receive headers allows the data path to be separated from the control path. Unlike operating system bypass, however, the operating system still fully manages the network resource and has relevant feedback about traffic and flows. Embodiments of the present disclosure can therefore address the challenges of networks with extreme bandwidth delay products (BWDP).

  12. Instrumentation for accelerators

    International Nuclear Information System (INIS)

    Sen, T.J.; De, T.K.; Ranganathan, M.K.; Basak, G.C.

    1989-01-01

    Along with the various system development for the accelerator, it was necessary to develop the instrumentation facility for the cyclotron. It started with the development of various vacuum instruments like ionization gauge control unit for measurement of pressure from 10 -4 torr to 10 -9 torr, discharge gauge control unit from 10 -4 torr to 10 -7 torr, thermocouple gauge control unit from 1 torr to 10 -3 torr. Process control instrumentation includes temperature measurement for freon cooled baffle and als o for low conductivity water. Control console required various digital panel meters for measurement of various parameters of the cyclotron. Various radiation monitoring instruments are also taken care of by the instrumentation facility. This paper describes in brief these various instruments. (author). 3 f igs

  13. ISOLDE - Accelerating Future

    CERN Multimedia

    CERN. Geneva

    2003-01-01

    Isotope Separation On-Line (ISOL) was first developed in Copenhagen in the late 50s. The technique was taken to CERN in the 60s and the CERN facility was given the name ISOLDE. The method is based on energetic protons hitting a solid target. The reaction products produced through spallation, fission and fragmentation are heated out in the form of an electrically neutral gas. In the subsequent steps the gas is ionized, accelerated and magnetically separated to produce isotopically pure beams for experiments in nuclear physics, atomic physics, astrophysics, solid state physics and for medical applications. An overview will be given of the physics at ISOLDE as well as over the techniques used to produce the necessary isotopes. Furthermore, a part of the talk will be dedicated to the future plans at ISOLDE including the proposal to build a next generation radioactive beam facility at CERN. The talk ends with a guided visit to the ISOLDE facility. Prerequisite knowledge: None.

  14. Pulsed electromagnetic acceleration

    Science.gov (United States)

    Jahn, R. G.; Vonjaskowsky, W. F.; Clark, K. E.

    1973-01-01

    Direct measurements of the power deposited in the anode of a multimegawatt MPD accelerator using thermocouples attached to a thin shell anode reveal a dramatic decrease in the fractional anode power from 50% at 200 KW input power to less than 10% at 20 MW power. The corresponding local power flux peak at a value of 10,000 W/sq cm at the lip of the anode exhaust orifice, a distribution traced to a corresponding peak in the local current density at the anode. A comparison of voltage-current characteristics and spectral photographs of the MPD discharge using quartz, boron nitride and plexiglas insulators with various mass injection configurations led to the identification of different voltage modes and regions of ablation free operation. The technique of piezoelectric impact pressure measurement in the MPD exhaust flow was refined to account for the effects due to probe yaw angle.

  15. Accelerated Corrosion Testing

    Science.gov (United States)

    1982-12-01

    cycle) AT1 0.24 AT5 2.4 k 1074 AT7 0.21 AT6 2.4 x 10-4 AT8 0.25 BIA 3.4 x 10-4 AT9 0.22 BL3 0.38 BL8 0.42 - .,14 of the specimen could be made common for...conditions in a cabi- net,79-82 and spray and fogs. 83-8 It was found35 that the data obtained in accelerated laboratory testing of metals in the presence...laboratory and outdoor exposure results. L4 29 F ,, . , • . .. -.. _.• ff’*• _, . . ._ • • • • 7 k. SALT SPRAY The salt- spray test involves exposure of

  16. GPU Accelerated Prognostics

    Science.gov (United States)

    Gorospe, George E., Jr.; Daigle, Matthew J.; Sankararaman, Shankar; Kulkarni, Chetan S.; Ng, Eley

    2017-01-01

    Prognostic methods enable operators and maintainers to predict the future performance for critical systems. However, these methods can be computationally expensive and may need to be performed each time new information about the system becomes available. In light of these computational requirements, we have investigated the application of graphics processing units (GPUs) as a computational platform for real-time prognostics. Recent advances in GPU technology have reduced cost and increased the computational capability of these highly parallel processing units, making them more attractive for the deployment of prognostic software. We present a survey of model-based prognostic algorithms with considerations for leveraging the parallel architecture of the GPU and a case study of GPU-accelerated battery prognostics with computational performance results.

  17. Accelerator vacuum system elements

    International Nuclear Information System (INIS)

    Sivokon', V.V.; Kobets, A.F.; Shvetsov, V.A.; Sivokon', L.V.

    1980-01-01

    Some elements of vacuum systems are investigated. Considerable attention has been given to the investigation into peculiarities in pumping out of a ionoguide for transportation of an accelerated charged particles beam the spread of which often attains a considerable length. The number of pumps over the ionoguide length is experimentally determined. It is shown that as a result of ionoguide warm-up the pumping out time is considerably reduced maximum permissible pressure is decreased by two orders and lesser rate of pump pumping out is required. The investigations have shown that when operating the ionoguide there is no necessity in setting up seals between the ionoguide and magnetodischarged pump. The causes of the phenomenon in which the pressure near the pump is greater than in the end of the ionoguide, are impurities carried in by the pump into the ionoguide volume and the pumping out capacity of the pressure converter

  18. SPS accelerating cavity

    CERN Multimedia

    CERN PhotoLab

    1976-01-01

    The SPS started up with 2 accelerating cavities (each consisting of 5 tank sections) in LSS3. They have a 200 MHz travelling wave structure (see 7411032 and 7802190) and 750 kW of power is fed to each of the cavities from a 1 MW tetrode power amplifier, located in a surface building above, via a coaxial transmission line. Clemens Zettler, builder of the SPS RF system, is standing at the side of one of the cavities. In 1978 and 1979 another 2 cavities were added and entered service in 1980. These were part of the intensity improvement programme and served well for the new role of the SPS as proton-antiproton collider. See also 7411032, 8011289, 8104138, 8302397.

  19. The Trichel pulse corona in N2 + CCl2F2 mixtures: the shape of pulses

    International Nuclear Information System (INIS)

    Vagnerova, L.; Dindosova, D.; Skalny, J.D.

    1998-01-01

    The formation of regular Trichel pulses in electronegative gaseous mixtures is studied experimentally, with emphasis on the consequences of different electron attachment mechanisms in the used gas mixtures on the behavior of the discharge. Negative ions are believed to be responsible for excitation of the Trichel pulses. The experimental data presented in the paper give evidence that the origin of the negative ions does not play any substantial role in the formation of the initial part of the Trichel pulses. (J.U.)

  20. CCL2 enhances pluripotency of human induced pluripotent stem cells by activating hypoxia related genes

    NARCIS (Netherlands)

    Hasegawa, Yuki; Tang, Dave; Takahashi, Naoko; Hayashizaki, Yoshihide; Forrest, Alistair R. R.; Suzuki, Harukazu; Kawaji, Hideya; Rehli, Michael; Baillie, J. Kenneth; de Hoon, Michiel J. L.; Haberle, Vanja; Lassmann, Timo; Kulakovskiy, Ivan V.; Lizio, Marina; Itoh, Masayoshi; Andersson, Robin; Mungall, Christopher J.; Meehan, Terrence F.; Schmeier, Sebastian; Bertin, Nicolas; Jørgensen, Mette; Dimont, Emmanuel; Arner, Erik; Schmidl, Christian; Schaefer, Ulf; Medvedeva, Yulia A.; Plessy, Charles; Vitezic, Morana; Severin, Jessica; Semple, Colin A.; Ishizu, Yuri; Young, Robert S.; Francescatto, Margherita; Alam, Intikhab; Albanese, Davide; Altschuler, Gabriel M.; Arakawa, Takahiro; Archer, John A. C.; Arner, Peter; Babina, Magda; Baker, Sarah; Balwierz, Piotr J.; Beckhouse, Anthony G.; Pradhan-Bhatt, Swati; Blake, Judith A.; Blumenthal, Antje; Bodega, Beatrice; Bonetti, Alessandro; Briggs, James; Brombacher, Frank; Burroughs, A. Maxwell; Califano, Andrea; Cannistraci, Carlo V.; Carbajo, Daniel; Chen, Yun; Chierici, Marco; Ciani, Yari; Clevers, Hans C.; Dalla, Emiliano; Davis, Carrie A.; Detmar, Michael; Diehl, Alexander D.; Dohi, Taeko; Drabløs, Finn; Edge, Albert S. B.; Edinger, Matthias; Ekwall, Karl; Endoh, Mitsuhiro; Enomoto, Hideki; Fagiolini, Michela; Fairbairn, Lynsey; Fang, Hai; Farach-Carson, Mary C.; Faulkner, Geoffrey J.; Favorov, Alexander V.; Fisher, Malcolm E.; Frith, Martin C.; Fujita, Rie; Fukuda, Shiro; Furlanello, Cesare; Furuno, Masaaki; Furusawa, Jun-ichi; Geijtenbeek, Teunis B.; Gibson, Andrew; Gingeras, Thomas; Goldowitz, Daniel; Gough, Julian; Guhl, Sven; Guler, Reto; Gustincich, Stefano; Ha, Thomas J.; Hamaguchi, Masahide; Hara, Mitsuko; Harbers, Matthias; Harshbarger, Jayson; Hasegawa, Akira; Hashimoto, Takehiro; Herlyn, Meenhard; Hitchens, Kelly J.; Ho Sui, Shannan J.; Hofmann, Oliver M.; Hoof, Ilka; Hori, Fumi; Huminiecki, Lukasz; Iida, Kei; Ikawa, Tomokatsu; Jankovic, Boris R.; Jia, Hui; Joshi, Anagha; Jurman, Giuseppe; Kaczkowski, Bogumil; Kai, Chieko; Kaida, Kaoru; Kaiho, Ai; Kajiyama, Kazuhiro; Kanamori-Katayama, Mutsumi; Kasianov, Artem S.; Kasukawa, Takeya; Katayama, Shintaro; Kato, Sachi; Kawaguchi, Shuji; Kawamoto, Hiroshi; Kawamura, Yuki I.; Kawashima, Tsugumi; Kempfle, Judith S.; Kenna, Tony J.; Kere, Juha; Khachigian, Levon M.; Kitamura, Toshio; Klinken, S. Peter; Knox, Alan J.; Kojima, Miki; Kojima, Soichi; Kondo, Naoto; Koseki, Haruhiko; Koyasu, Shigeo; Krampitz, Sarah; Kubosaki, Atsutaka; Kwon, Andrew T.; Laros, Jeroen F. J.; Lee, Weonju; Lennartsson, Andreas; Li, Kang; Lilje, Berit; Lipovich, Leonard; Mackay-sim, Alan; Manabe, Ri-ichiroh; Mar, Jessica C.; Marchand, Benoit; Mathelier, Anthony; Mejhert, Niklas; Meynert, Alison; Mizuno, Yosuke; Morais, David A. de Lima; Morikawa, Hiromasa; Morimoto, Mitsuru; Moro, Kazuyo; Motakis, Efthymios; Motohashi, Hozumi; Mummery, Christine L.; Murata, Mitsuyoshi; Nagao-Sato, Sayaka; Nakachi, Yutaka; Nakahara, Fumio; Nakamura, Toshiyuki; Nakamura, Yukio; Nakazato, Kenichi; van Nimwegen, Erik; Ninomiya, Noriko; Nishiyori, Hiromi; Noma, Shohei; Nozaki, Tadasuke; Ogishima, Soichi; Ohkura, Naganari; Ohmiya, Hiroko; Ohno, Hiroshi; Ohshima, Mitsuhiro; Okada-Hatakeyama, Mariko; Okazaki, Yasushi; Orlando, Valerio; Ovchinnikov, Dmitry A.; Pain, Arnab; Passier, Robert; Patrikakis, Margaret; Persson, Helena; Piazza, Silvano; Prendergast, James G. D.; Rackham, Owen J. L.; Ramilowski, Jordan A.; Rashid, Mamoon; Ravasi, Timothy; Rizzu, Patrizia; Roncador, Marco; Roy, Sugata; Rye, Morten B.; Saijyo, Eri; Sajantila, Antti; Saka, Akiko; Sakaguchi, Shimon; Sakai, Mizuho; Sato, Hiroki; Satoh, Hironori; Savvi, Suzana; Saxena, Alka; Schneider, Claudio; Schultes, Erik A.; Schulze-Tanzil, Gundula G.; Schwegmann, Anita; Sengstag, Thierry; Sheng, Guojun; Shimoji, Hisashi; Shimoni, Yishai; Shin, Jay W.; Simon, Christophe; Sugiyama, Daisuke; Sugiyama, Takaaki; Suzuki, Masanori; Suzuki, Naoko; Swoboda, Rolf K.; 't Hoen, Peter A. C.; Tagami, Michihira; Takai, Jun; Tanaka, Hiroshi; Tatsukawa, Hideki; Tatum, Zuotian; Thompson, Mark; Toyoda, Hiroo; Toyoda, Tetsuro; Valen, Eivind; van de Wetering, Marc; van den Berg, Linda M.; Verardo, Roberto; Vijayan, Dipti; Vorontsov, Ilya E.; Wasserman, Wyeth W.; Watanabe, Shoko; Wells, Christine A.; Winteringham, Louise N.; Wolvetang, Ernst; Wood, Emily J.; Yamaguchi, Yoko; Yamamoto, Masayuki; Yoneda, Misako; Yonekura, Yohei; Yoshida, Shigehiro; Zabierowski, Suzan E.; Zhang, Peter G.; Zhao, Xiaobei; Zucchelli, Silvia; Summers, Kim M.; Daub, Carsten O.; Kawai, Jun; Heutink, Peter; Hide, Winston; Freeman, Tom C.; Lenhard, Boris; Bajic, Vladimir B.; Taylor, Martin S.; Makeev, Vsevolod J.; Sandelin, Albin; Hume, David A.; Carninci, Piero

    2014-01-01

    Standard culture of human induced pluripotent stem cells (hiPSCs) requires basic Fibroblast Growth Factor (bFGF) to maintain the pluripotent state, whereas hiPSC more closely resemble epiblast stem cells than true naive state ES which requires LIF to maintain pluripotency. Here we show that

  1. Neuronal CC chemokines : the distinct roles of CCL21 and CCL2 in neuropathic pain

    NARCIS (Netherlands)

    Biber, Knut; Boddeke, Erik

    2014-01-01

    The development of neuropathic pain in response to peripheral nerve lesion for a large part depends on microglia located at the dorsal horn of the spinal cord. Thus the injured nerve initiates a response of microglia, which represents the start of a cascade of events that leads to neuropathic pain

  2. Progress in advanced accelerator concepts

    International Nuclear Information System (INIS)

    Sessler, A.M.

    1994-08-01

    A review is given of recent progress in this field, drawing heavily upon material presented at the Workshop on Advanced Accelerator Concepts, The Abbey, June 12--18, 1994. Attention is addressed to (1) plasma based concepts, (2) photo-cathodes, (3) radio frequency sources and Two-Beam Accelerators, (4) near and far-field schemes (including collective accelerators), (5) beam handling and conditioning, and (6) exotic collider concepts (such as photon colliders and muon colliders)

  3. Accelerator control systems in China

    International Nuclear Information System (INIS)

    Yao Chihyuan

    1992-01-01

    Three accelerator facilities were built in the past few years, the 2.8 GeV electron positron collider BEPC, the heavy ion SSC cyclotron accelerator HIRFL and the 800 MeV synchrotron radiation storage ring HESYRL. Aimed at different research areas, they represent a new generation of accelerator in China. This report describes the design philosophy, the structure, performance as well as future improvements of the control systems of the these facilities. (author)

  4. Accelerator development for medical applications

    International Nuclear Information System (INIS)

    Tanabe, Eiji

    2007-01-01

    Electron linear accelerators have been widely used in medical applications, especially in radiation therapy for cancer treatment. There are more than 7,000 medical electron linear accelerators in the world, treating over 250,000 patients per day. This paper reviews the current status of accelerator applications and technologies in radiation therapy, and presents the anticipated requirements for advanced radiation therapy technology in the foreseeable future. (author)

  5. Converging-barrel plasma accelerator

    International Nuclear Information System (INIS)

    Paine, T.O.

    1971-01-01

    The invention comprises a device for generating and accelerating plasma to extremely high velocity, while focusing the plasma to a decreasing cross section for attaining a very dense high-velocity plasma burst capable of causing nuclear fusion reactions. A converging coaxial accelerator-electrode configuration is employed with ''high-pressure'' gas injection in controlled amounts to achieve acceleration by deflagration and focusing by the shaped electromagnetic fields. (U.S.)

  6. Special issue - Applying the accelerator

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    T'he CERN Courier is the international journal of high energy physics, covering current developments in and around this branch of basic science. A recurrent theme is applying the technology developed for particle accelerators, the machines which produce beams of high energy particles for physics experiments. Twentieth-century science is full of similar examples of applications derived from pure research. This special issue of the CERN Courier is given over to one theme - the applications of accelerators. Accelerator systems and facilities are normally associated with highenergy particle physics research, the search for fundamental particles and the quest to understand the physics of the Big Bang. To the layman, accelerator technology has become synonymous with large and expensive machines, exploiting the most modern technology for basic research. In reality, the range of accelerators and their applications is much broader. A vast number of accelerators, usually much smaller and operating for specific applications, create wealth and directly benefit the population, particularly in the important areas of healthcare, energy and the environment. There are well established applications in diagnostic and therapeutic medicine for research and routine clinical treatments. Accelerators and associated technologies are widely employed by industry for manufacturing and process control. In fundamental and applied research, accelerator systems are frequently used as tools. The biennial conference on the Applications of Accelerators in Industry and Research at Denton, Texas, attracts a thousand participants. This special issue of the CERN Courier includes articles on major applications, reflecting the diversity and value of accelerator technology. Under Guest Editor Dewi Lewis of Amersham International, contributions from leading international specialists with experience of the application end of the accelerator chain describe their fields of direct interest. The

  7. VEBA relativistic electron accelerator

    International Nuclear Information System (INIS)

    Parker, R.K.; Ury, M.

    1975-01-01

    The VEBA high-current, relativistic electron accelerator was designed and constructed at NRL for applications in the study of high-power microwave sources. To meet the requirements of this study, the accelerator was designed for operation in either a short (60 nsec) or long (2.2 μsec) pulse mode. The short-pulse mode has been in operation for nearly two years and has proven to be an extremely reliable design. The design of the long-pulse mode is now complete and component fabrication will soon be underway. The pulse-forming network in the short-pulse mode is an unbalanced, water Blumlein with an output impedance of 9.2 Ω. The Blumlein is pulse charged by a 17 stage Marx generator which has a series capacitance of 29.4 nF. By transmission along a tapered coaxial line, the output pulse is transformed to 20 Ω, and the voltage developed across a matched load increases to a maximum of 2.3 MV. The proposed conversion to the long-pulse mode will require the Blumlein and transformer sections be removed and the diode assembly be attached directly to the oversized Marx tank. The direct coupling between the Marx and the Blumlein will then be replaced by two nested water capacitors, which are shunted by spiral inductors. When coupled in series with the Marx, this output filter will form a three-section, voltage-fed, Guillemin (type A), pulse-forming network with a characteristic impedance of 40 Ω and a maximum output voltage of 0.9 MV. (auth)

  8. Muon Collider Progress: Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Zisman, Michael S.

    2011-09-10

    A muon collider would be a powerful tool for exploring the energy-frontier with leptons, and would complement the studies now under way at the LHC. Such a device would offer several important benefits. Muons, like electrons, are point particles so the full center-of-mass energy is available for particle production. Moreover, on account of their higher mass, muons give rise to very little synchrotron radiation and produce very little beamstrahlung. The first feature permits the use of a circular collider that can make efficient use of the expensive rf system and whose footprint is compatible with an existing laboratory site. The second feature leads to a relatively narrow energy spread at the collision point. Designing an accelerator complex for a muon collider is a challenging task. Firstly, the muons are produced as a tertiary beam, so a high-power proton beam and a target that can withstand it are needed to provide the required luminosity of ~1 × 10{sup 34} cm{sup –2}s{sup –1}. Secondly, the beam is initially produced with a large 6D phase space, which necessitates a scheme for reducing the muon beam emittance (“cooling”). Finally, the muon has a short lifetime so all beam manipulations must be done very rapidly. The Muon Accelerator Program, led by Fermilab and including a number of U.S. national laboratories and universities, has undertaken design and R&D activities aimed toward the eventual construction of a muon collider. Design features of such a facility and the supporting R&D program are described.

  9. Swedish earthquakes and acceleration probabilities

    International Nuclear Information System (INIS)

    Slunga, R.

    1979-03-01

    A method to assign probabilities to ground accelerations for Swedish sites is described. As hardly any nearfield instrumental data is available we are left with the problem of interpreting macroseismic data in terms of acceleration. By theoretical wave propagation computations the relation between seismic strength of the earthquake, focal depth, distance and ground accelerations are calculated. We found that most Swedish earthquake of the area, the 1904 earthquake 100 km south of Oslo, is an exception and probably had a focal depth exceeding 25 km. For the nuclear power plant sites an annual probability of 10 -5 has been proposed as interesting. This probability gives ground accelerations in the range 5-20 % for the sites. This acceleration is for a free bedrock site. For consistency all acceleration results in this study are given for bedrock sites. When applicating our model to the 1904 earthquake and assuming the focal zone to be in the lower crust we get the epicentral acceleration of this earthquake to be 5-15 % g. The results above are based on an analyses of macrosismic data as relevant instrumental data is lacking. However, the macroseismic acceleration model deduced in this study gives epicentral ground acceleration of small Swedish earthquakes in agreement with existent distant instrumental data. (author)

  10. Superconducting Radiofrequency (SRF) Acceleration Technology

    Data.gov (United States)

    Federal Laboratory Consortium — SRF cavities enable accelerators to increase particle beam energy levels while minimizing the use of electrical power by all but eliminating electrical resistance....

  11. The intense proton accelerator program

    International Nuclear Information System (INIS)

    Kaneko, Yoshihiko

    1990-01-01

    The Science and Technology Agency of Japan has formulated the OMEGA project, in which incineration of nuclear wastes by use of accelerators is defined as one of the important tasks. Japan Atomic Energy Research Institute (JAERI) has been engaged for several years in basic studies in incineration technology with use of an intense proton linear accelerator. The intense proton accelerator program intends to provide a large scale proton linear accelerator called Engineering Test Accelerator. The principal purpose of the accelerator is to develop nuclear waste incineration technology. The accelerator will also be used for other industrial applications and applied science studies. The present report further outlines the concept of incineration of radio-activities of nuclear wastes, focusing on nuclear reactions and a concept of incineration plant. Features of Engineering Test Accelerator are described focusing on the development of the accelerator, and research and development of incineration technology. Applications of science and technology other than nuclear waste incineration are also discussed. (N.K.)

  12. Overview of SSC accelerator requirements

    International Nuclear Information System (INIS)

    Dugan, G.

    1992-03-01

    This paper will present a general overview of the requirements of the Superconducting Super Collider (SSC) accelerators. Each accelerator in the injector chain will be discussed separately, followed by a discussion of the collider itself. In conclusion, the top level requirements of the overall accelerator system will be presented. For each accelerator, the primary operating parameters will be presented in tabular form. A brief narrative discussion of the principal technical features of each machine will be given. Finally, the principal technical design challenges for the machine will be noted, together with the currently planned solution to these challenges

  13. SHORT ACCELERATION TIMES FROM SUPERDIFFUSIVE SHOCK ACCELERATION IN THE HELIOSPHERE

    Energy Technology Data Exchange (ETDEWEB)

    Perri, S.; Zimbardo, G., E-mail: silvia.perri@fis.unical.it [Dipartimento di Fisica, Università della Calabria, Ponte P. Bucci, I-87036 Rende (Italy)

    2015-12-10

    The analysis of time profiles of particles accelerated at interplanetary shocks allows particle transport properties to be inferred. The frequently observed power-law decay upstream, indeed, implies a superdiffusive particle transport when the level of magnetic field variance does not change as the time interval from the shock front increases. In this context, a superdiffusive shock acceleration (SSA) theory has been developed, allowing us to make predictions of the acceleration times. In this work we estimate for a number of interplanetary shocks, including the solar wind termination shock, the acceleration times for energetic protons in the framework of SSA and we compare the results with the acceleration times predicted by standard diffusive shock acceleration. The acceleration times due to SSA are found to be much shorter than in the classical model, and also shorter than the interplanetary shock lifetimes. This decrease of the acceleration times is due to the scale-free nature of the particle displacements in the framework of superdiffusion. Indeed, very long displacements are possible, increasing the probability for particles far from the front of the shock to return, and short displacements have a high probability of occurrence, increasing the chances for particles close to the front to cross the shock many times.

  14. CAS CERN Accelerator School superconductivity in particle accelerators

    International Nuclear Information System (INIS)

    Turner, S.

    1989-01-01

    One of the objectives of the CERN Accelerator School is to run courses on specialised topics in the particle accelerator field. The present volume contains the proceedings of one such course, this time organized in conjunction with the Deutsches Elektronen Synchrotron (DESY) on the subject of superconductivity in particle accelerators. This course reflects the very considerable progress made over the last few years in the use of the technology for the magnet and radio-frequency systems of many large and small accelerators already in use or nearing completion, while also taking account of the development work now going on for future machines. The lectures cover the theory of superconductivity, cryogenics and accelerator magnets and cavities, while the seminars include superfluidity, superconductors, special magnets and the prospects for high-temperature superconductors. (orig.)

  15. Natural Acceleration: Supporting Creative Trajectories

    Science.gov (United States)

    Cohen, LeoNora M.

    2011-01-01

    "Natural acceleration" happens through an internal fire that burns to learn and may transcend school boundaries. Based on their passionate interests and connections with a domain, children who hunger for domain understandings outside school curricula require different types of acceleration, motivated by these interests. The lifeworks,…

  16. Particle acceleration by electromagnetic pulses

    International Nuclear Information System (INIS)

    Lai, H.M.

    1982-01-01

    Particle interaction with plane electromagnetic pulses is studied. It is shown that particle acceleration by a wavy pulse, depending on the shape of the pulse, may not be small. Further, a diffusive-type particle acceleration by multiple weak pulses is described and discussed. (author)

  17. Shielding experiments for accelerator facilities

    Energy Technology Data Exchange (ETDEWEB)

    Nakashima, Hiroshi; Tanaka, Susumu; Sakamoto, Yukio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment] [and others

    2000-06-01

    A series of shielding experiments was carried out by using AVF cyclotron accelerator of TIARA at JAERI in order to validate shielding design methods for accelerator facilities in intermediate energy region. In this paper neutron transmission experiment through thick shields and radiation streaming experiment through a labyrinth are reported. (author)

  18. Shielding experiments for accelerator facilities

    International Nuclear Information System (INIS)

    Nakashima, Hiroshi; Tanaka, Susumu; Sakamoto, Yukio

    2000-01-01

    A series of shielding experiments was carried out by using AVF cyclotron accelerator of TIARA at JAERI in order to validate shielding design methods for accelerator facilities in intermediate energy region. In this paper neutron transmission experiment through thick shields and radiation streaming experiment through a labyrinth are reported. (author)

  19. The ISR and accelerator physics

    International Nuclear Information System (INIS)

    Johnsen, K.

    1986-01-01

    The paper reviews the development of the Intersecting Storage Rings (ISR), Cern, over the 12 years and 11 months of operation. The early history and some features of its construction are outlined. The accelerator physics at the ISR includes: studies to improve the performance of the facility, accelerator studies associated with technology eg lifetime of bunched beams, and resulting ISR performance. (U.K.)

  20. Software for virtual accelerator designing

    International Nuclear Information System (INIS)

    Kulabukhova, N.; Ivanov, A.; Korkhov, V.; Lazarev, A.

    2012-01-01

    The article discusses appropriate technologies for software implementation of the Virtual Accelerator. The Virtual Accelerator is considered as a set of services and tools enabling transparent execution of computational software for modeling beam dynamics in accelerators on distributed computing resources. Distributed storage and information processing facilities utilized by the Virtual Accelerator make use of the Service-Oriented Architecture (SOA) according to a cloud computing paradigm. Control system tool-kits (such as EPICS, TANGO), computing modules (including high-performance computing), realization of the GUI with existing frameworks and visualization of the data are discussed in the paper. The presented research consists of software analysis for realization of interaction between all levels of the Virtual Accelerator and some samples of middle-ware implementation. A set of the servers and clusters at St.-Petersburg State University form the infrastructure of the computing environment for Virtual Accelerator design. Usage of component-oriented technology for realization of Virtual Accelerator levels interaction is proposed. The article concludes with an overview and substantiation of a choice of technologies that will be used for design and implementation of the Virtual Accelerator. (authors)

  1. Accelerated Learning 1985-1986.

    Science.gov (United States)

    Cullen, Audrey; And Others

    A second language teaching technique using relaxation, imagination, and music to accelerate the learning process is imagination, and music to accelerate the learning process is discussed. Part 1 describes the classroom setting and the stages and processes of the technique. Part 2 outlines the theory and sources of the method in the literature of…

  2. Ion Acceleration Inside Foreshock Transients

    Science.gov (United States)

    Liu, Terry Z.; Lu, San; Angelopoulos, Vassilis; Lin, Yu; Wang, X. Y.

    2018-01-01

    Recent observations upstream of Earth's bow shock have revealed that foreshock transients can not only accelerate solar wind ions by reflection at their upstream boundaries but may also accelerate ions inside them. Evidence for the latter comes from comparisons of ion spectra inside and outside the cores, and from evidence of leakage of suprathermal ions from the cores. However, definite evidence for, and the physics of, ion acceleration in the foreshock transients are still open questions. Using case studies of foreshock transients from Time History of Events and Macroscale Interactions during Substorms observations, we reveal an ion acceleration mechanism in foreshock transients that is applicable to 25% of the transients. The ion energy flux is enhanced between several keV to tens of keV in the cores. We show that these energetic ions are reflected at the earthward moving boundary of foreshock transients, are accelerated through partial gyration along the convection electric field, and can leak out both upstream and downstream of the foreshock transients. Using ions moving self-consistently with a generic 3-D global hybrid simulation of a foreshock transient, we confirm this physical picture of ion acceleration and leakage. These accelerated ions could be further accelerated at the local bow shock and repopulate the foreshock, increasing the efficacy of solar wind-magnetosphere interactions.

  3. Modern instrumentation of electrostatic accelerators

    International Nuclear Information System (INIS)

    Repnow, R.

    1986-01-01

    For diagnostics and control of electrostatic accelerators complex electronic systems are used also inside the accelerator vessel to an increasing extent. Methods for protection of the equipment and for the data transmission are discussed. Several existing digital control systems are compared and the advantages of digital closed loop regulation systems are indicated. (orig.)

  4. Perspective of culster rapid acceleration

    International Nuclear Information System (INIS)

    Iwata, Yasushi

    1994-01-01

    Fast cluster ion beam is a new radiation beam which is characterized by high particle density and very short pulse when the composing atom group is considered as one ion pulse. As an important research which utilizes these features, the elucidation of nonlinear atomic collision dynamics is conceivable. The condition under which the nonlinear atomic collision occurs is discussed, and that in the relation of the acceleration energy of an ion beam with the particle number density is shown. The history and the present status of cluster rapid acceleration are reported. According to the balance of the electrostatic potential and bond energy of cluster ions, there is the limit in its allowable charge, and the rapid acceleration of cluster ions is made difficult. Accordingly, the method of doing preceding acceleration with an electrostatic accelerator and the acceleration to higher velocity with a RFQ accelerator (Lyons method) is the excellent acceleration system. The new charge conversion method by photoionization is proposed, and it is explained. The examples that suggest the possibility of the occurrence of nonlinear atomic collision by a single atom ion beam are introduced. (K.I.)

  5. General purpose programmable accelerator board

    Science.gov (United States)

    Robertson, Perry J.; Witzke, Edward L.

    2001-01-01

    A general purpose accelerator board and acceleration method comprising use of: one or more programmable logic devices; a plurality of memory blocks; bus interface for communicating data between the memory blocks and devices external to the board; and dynamic programming capabilities for providing logic to the programmable logic device to be executed on data in the memory blocks.

  6. Laboratory of acceleration mass spectrometry

    International Nuclear Information System (INIS)

    Hybler, P.; Chrapan, J.

    2002-01-01

    In this paper authors describe the principle of the method of acceleration mass spectrometry and the construction plans of this instrument at the Faculty of ecology and environmental sciences in Banska Stiavnica. Using of this instrument for radiocarbon dating is discussed. A review of laboratories with acceleration mass spectrometry is presented

  7. Thomas Edison Accelerated Elementary School.

    Science.gov (United States)

    Levin, Henry M.; Chasin, Gene

    This paper describes early outcomes of a Sacramento, California, elementary school that participated in the Accelerated Schools Project. The school, which serves many minority and poor students, began training for the project in 1992. Accelerated Schools were designed to advance the learning rate of students through a gifted and talented approach,…

  8. COMPASS Accelerator Design Technical Overview

    Energy Technology Data Exchange (ETDEWEB)

    Nanni, Emilio; Dolgashev, Valery; Tantawi, Sami; Neilson, Jeff; /SLAC

    2016-03-14

    This report is a survey of technical options for generating a MeV-class accelerator for space based science applications. The survey was performed focusing on the primary technical requirements of the accelerator in the context of a satellite environment with its unique challenges of limited electrical power (PE), thermal isolation, dimensions, payload requirement and electrical isolation.

  9. Ion sources for electrostatic accelerators

    International Nuclear Information System (INIS)

    Hellborg, R.

    1998-01-01

    Maybe the most important part of an electrostatic accelerator system, and also often the most tricky part is the ion source. There has been a rapid growth in activity in ion-source research and development during the last two to three decades. Some of these developments have also been of benefit to electrostatic accelerator users. In this report some of the different types of ion sources used in electrostatic accelerators are described. The list is not complete but more an overview of some of the more commonly used sources. The description is divided into two groups; positive ion sources for single stage electrostatic accelerators and negative ion sources for two stages (i.e. tandem) accelerators

  10. Industrial accelerators and their applications

    CERN Document Server

    Hamm, Marianne E

    2012-01-01

    This unique new book is a comprehensive review of the many current industrial applications of particle accelerators, written by experts in each of these fields. Readers will gain a broad understanding of the principles of these applications, the extent to which they are employed, and the accelerator technology utilized. The book also serves as a thorough introduction to these fields for non-experts and laymen. Due to the increased interest in industrial applications, there is a growing interest among accelerator physicists and many other scientists worldwide in understanding how accelerators are used in various applications. The government agencies that fund scientific research with accelerators are also seeking more information on the many commercial applications that have been or can be developed with the technology developments they are funding. Many industries are also doing more research on how they can improve their products or processes using particle beams.

  11. SHEAR ACCELERATION IN EXPANDING FLOWS

    Energy Technology Data Exchange (ETDEWEB)

    Rieger, F. M. [ZAH, Institut für Theoretische Astrophysik, Universität Heidelberg, Philosophenweg 12, D-69120 Heidelberg (Germany); Duffy, P., E-mail: frank.rieger@mpi-hd.mpg.de, E-mail: peter.duffy@ucd.ie [University College Dublin, Belfield, Dublin 4 (Ireland)

    2016-12-10

    Shear flows are naturally expected to occur in astrophysical environments and potential sites of continuous non-thermal Fermi-type particle acceleration. Here we investigate the efficiency of expanding relativistic outflows to facilitate the acceleration of energetic charged particles to higher energies. To this end, the gradual shear acceleration coefficient is derived based on an analytical treatment. The results are applied to the context of the relativistic jets from active galactic nuclei. The inferred acceleration timescale is investigated for a variety of conical flow profiles (i.e., power law, Gaussian, Fermi–Dirac) and compared to the relevant radiative and non-radiative loss timescales. The results exemplify that relativistic shear flows are capable of boosting cosmic-rays to extreme energies. Efficient electron acceleration, on the other hand, requires weak magnetic fields and may thus be accompanied by a delayed onset of particle energization and affect the overall jet appearance (e.g., core, ridge line, and limb-brightening).

  12. SPS RF Accelerating Cavity

    CERN Multimedia

    1979-01-01

    This picture shows one of the 2 new cavities installed in 1978-1979. The main RF-system of the SPS comprises four cavities: two of 20 m length and two of 16.5 m length. They are all installed in one long straight section (LSS 3). These cavities are of the travelling-wave type operating at a centre frequency of 200.2 MHz. They are wideband, filling time about 700 ns and untuned. The power amplifiers, using tetrodes are installed in a surface building 200 m from the cavities. Initially only two cavities were installed, a third cavity was installed in 1978 and a forth one in 1979. The number of power amplifiers was also increased: to the first 2 MW plant a second 2 MW plant was added and by end 1979 there were 8 500 kW units combined in pairs to feed each of the 4 cavities with up to about 1 MW RF power, resulting in a total accelerating voltage of about 8 MV. See also 7412016X, 7412017X, 7411048X

  13. LHC Dipoles Accelerate

    CERN Multimedia

    2001-01-01

    Andrezej Siemko (left), Peter Sievers (centre), and Lucio Rossi (right), have the exciting challenge of preparing and testing 2000 magnets for the LHC. The LHC is going to require a lot of powerful magnets by the time it begins operation in 2006. More specifically, it is going to need 130 special magnets, 400 quadrupoles, and a whopping 1250 dipoles! Preparing and testing these magnets for the conditions they will encounter in the LHC is not an easy task. But evaluation of the most recently received magnet, from the German company Noell, is showing that while the monumental task of receiving and testing nearly 2000 magnets is going to be exhausting, the goals are definitely attainable. At the moment and over the next year, pre-series magnets (the magnets that CERN uses to fine tune performance) are arriving slowly (90 in total will arrive), but by 2003 the rate of series magnet arrival will accelerate to 9 per week, that's over 450 in a single year! And working with these magnets when they arrive is tough. ...

  14. Actinides, accelerators and erosion

    Directory of Open Access Journals (Sweden)

    Fifield L.K.

    2012-10-01

    Full Text Available Fallout isotopes can be used as artificial tracers of soil erosion and sediment accumulation. The most commonly used isotope to date has been 137Cs. Concentrations of 137Cs are, however, significantly lower in the Southern Hemisphere, and furthermore have now declined to 35% of original values due to radioactive decay. As a consequence the future utility of 137Cs is limited in Australia, with many erosion applications becoming untenable within the next 20 years, and there is a need to replace it with another tracer. Plutonium could fill this role, and has the advantages that there were six times as many atoms of Pu as of 137Cs in fallout, and any loss to decay has been negligible due to the long half-lives of the plutonium isotopes. Uranium-236 is another long-lived fallout isotope with significant potential for exploitation as a tracer of soil and sediment movement. Uranium is expected to be more mobile in soils than plutonium (or caesium, and hence the 236U/Pu ratio will vary with soil depth, and so could provide an independent measure of the amount of soil loss. In this paper we discuss accelerator based ultra-sensitive measurements of plutonium and 236U isotopes and their advantages over 137Cs as tracers of soil erosion and sediment movement.

  15. EXHIBITION: Accelerated Particles

    CERN Multimedia

    2004-01-01

    An exhibition of plastic arts and two evenings of performances by sound and visual artists as part of CERN's 50th anniversary celebrations. Fifty candles for CERN, an international laboratory renowned for fundamental research, is a cause for celebration. Since March this year, Geneva and neighbouring parts of France have been the venues for a wealth of small and large-scale events, which will continue until November. Given CERN's location in the commune of Meyrin, the ForuMeyrin is hosting exhibitions of plastic arts and performances entitled: Accelerated Particles. Several works will be exhibited and performed in two 'salons'. Salon des matières: An exhibition of plastic arts From Tues 12 October to Wed 3 November 2004 Tuesdays to Fridays: 16:00 to 19:00 Saturdays: 14:00 to 18:00 Exhibition open late on performance nights, entrance free Salon des particules: Musical and visual performances Tues 12 and Mon 25 October from 20:00 to 23:00 Preview evening for both events: Tues 12 October from 18:...

  16. EXHIBITION: Accelerated Particles

    CERN Multimedia

    2004-01-01

    http://www.cern.ch/cern50/ An exhibition of plastic arts and two evenings of performances by sound and visual artists as part of CERN's fiftieth anniversary celebrations. The fiftieth anniversary of a world famous organization like CERN, an international laboratory specializing in fundamental research, is a cause for celebration. Since March this year, Geneva and neighbouring parts of France have been the venues for a wealth of small and large-scale events, which will continue until November. Given CERN's location in the commune of Meyrin, the ForuMeyrin is hosting two "salons" consisting of an exhibition of plastic arts and evenings of music and visual arts performances with the collective title of "Accelerated Particles". Several works will be exhibited and performed. Salon des matières: An exhibition of plastic arts Until Wednesday 3 November 2004. Tuesdays to Fridays: 4.00 p.m. to 7.00 p.m. Saturdays: 2.00 p.m. to 6.00 p.m. Doors open late on the evening of the performances. Salon des ...

  17. RFQ accelerator tuning system

    International Nuclear Information System (INIS)

    Bolie, V.W.

    1990-01-01

    A cooling system is provided for maintaining a preselected operating temperature in a device, which may be an RFQ accelerator, having a variable heat removal requirement, by circulating a cooling fluid through a cooling system remote from the device. Internal sensors in the device enable an estimated error signal to be generated from parameters which are indicative of the heat removal requirement from the device. Sensors are provided at predetermined locations in the cooling system for outputting operational temperature signals. Analog and digital computers define a control signal functionally related to the temperature signals and the estimated error signal, where the control signal is defined effective to return the device to the preselected operating temperature in a stable manner. The cooling system includes a first heat sink responsive to a first portion of the control signal to remove heat from a major portion of the circulating fluid. A second heat sink is responsive to a second portion of the control signal to remove heat from a minor portion of the circulating fluid. The cooled major and minor portions of the circulating fluid are mixed in response to a mixing portion of the control signal, which is effective to proportion the major and minor portions of the circulating fluid to establish a mixed fluid temperature which is effective to define the preselected operating temperature for the remote device. In an RFQ environment the stable temperature control enables the resonant frequency of the device to be maintained at substantially a predetermined value during transient operations. 3 figs

  18. Is Global Warming Accelerating?

    Science.gov (United States)

    Shukla, J.; Delsole, T. M.; Tippett, M. K.

    2009-12-01

    A global pattern that fluctuates naturally on decadal time scales is identified in climate simulations and observations. This newly discovered component, called the Global Multidecadal Oscillation (GMO), is related to the Atlantic Meridional Oscillation and shown to account for a substantial fraction of decadal fluctuations in the observed global average sea surface temperature. IPCC-class climate models generally underestimate the variance of the GMO, and hence underestimate the decadal fluctuations due to this component of natural variability. Decomposing observed sea surface temperature into a component due to anthropogenic and natural radiative forcing plus the GMO, reveals that most multidecadal fluctuations in the observed global average sea surface temperature can be accounted for by these two components alone. The fact that the GMO varies naturally on multidecadal time scales implies that it can be predicted with some skill on decadal time scales, which provides a scientific rationale for decadal predictions. Furthermore, the GMO is shown to account for about half of the warming in the last 25 years and hence a substantial fraction of the recent acceleration in the rate of increase in global average sea surface temperature. Nevertheless, in terms of the global average “well-observed” sea surface temperature, the GMO can account for only about 0.1° C in transient, decadal-scale fluctuations, not the century-long 1° C warming that has been observed during the twentieth century.

  19. Cosmic transparency and acceleration

    Science.gov (United States)

    Holanda, R. F. L.; Pereira, S. H.; Jain, Deepak

    2018-01-01

    In this paper, by considering an absorption probability independent of photon wavelength, we show that current type Ia supernovae (SNe Ia) and gamma-ray burst (GRB) observations plus high-redshift measurements of the cosmic microwave background (CMB) radiation temperature support cosmic acceleration regardless of the transparent-universe assumption. Two flat scenarios are considered in our analyses: the Λ CDM model and a kinematic model. We consider τ (z )=2 ln (1 +z )ɛ, where τ (z ) denotes the opacity between an observer at z =0 and a source at z . This choice is equivalent to deforming the cosmic distance duality relation as DLDA-1=(1 +z )2+ɛ and, if the absorption probability is independent of photon wavelength, the CMB temperature evolution law is TCMB(z )=T0(1 +z )1+2 ɛ /3. By marginalizing on the ɛ parameter, our analyses rule out a decelerating universe at 99.99% C.L. for all scenarios considered. Interestingly, by considering only SNe Ia and GRBs observations, we obtain that a decelerated universe—indicated by ΩΛ≤0.33 and q0>0 —is ruled out around 1.5 σ C.L. and 2 σ C.L., respectively, regardless of the transparent-universe assumption.

  20. Accelerating momentum for change!

    Science.gov (United States)

    Wenzel, S; Panetta, J

    1995-05-01

    As we develop strategies to compete globally, we are challenged with integrating our resources to execute these strategies effectively. Many companies are in the midst of dramatic shifts in corporate cultures, giving more responsibility to employees while raising expectations for their performance. The extent of these changes is far reaching and brings significant challenges to both employees and corporations. This article is a continuation of the evolution (over five years) of a corrective action/continuous improvement process implemented at Exide Electronics. It discusses organizational structures, including steering committees, corrective action teams, task teams, and work cells. Specific expectations, goals, and results of the teams are presented, along with ground rules for functioning within the organization. After structuring the organization and coordinating the resources effectively, the next challenge is accelerating momentum for change. The presentation also discusses the evolutionary process required to make a culture focused on change, including ongoing communication and feedback, constant evaluation and direction of the process, and measuring and paying for performance.

  1. Remote handling and accelerators

    International Nuclear Information System (INIS)

    Wilson, M.T.

    1983-01-01

    The high-current levels of contemporary and proposed accelerator facilities induce radiation levels into components, requiring consideration be given to maintenance techniques that reduce personnel exposure. Typical components involved include beamstops, targets, collimators, windows, and instrumentation that intercepts the direct beam. Also included are beam extraction, injection, splitting, and kicking regions, as well as purposeful spill areas where beam tails are trimmed and neutral particles are deposited. Scattered beam and secondary particles activate components all along a beamline such as vacuum pipes, magnets, and shielding. Maintenance techniques vary from hands-on to TV-viewed operation using state-of-the-art servomanipulators. Bottom- or side-entry casks are used with thimble-type target and diagnostic assemblies. Long-handled tools are operated from behind shadow shields. Swinging shield doors, unstacking block, and horizontally rolling shield roofs are all used to provide access. Common to all techniques is the need to make operations simple and to provide a means of seeing and reaching the area

  2. Energy Innovation Acceleration Program

    Energy Technology Data Exchange (ETDEWEB)

    Wolfson, Johanna [Fraunhofer USA Inc., Center for Sustainable Energy Systems, Boston, MA (United States)

    2015-06-15

    The Energy Innovation Acceleration Program (IAP) – also called U-Launch – has had a significant impact on early stage clean energy companies in the Northeast and on the clean energy economy in the Northeast, not only during program execution (2010-2014), but continuing into the future. Key results include: Leverage ratio of 105:1; $105M in follow-on funding (upon $1M investment by EERE); At least 19 commercial products launched; At least 17 new industry partnerships formed; At least $6.5M in revenue generated; >140 jobs created; 60% of assisted companies received follow-on funding within 1 year of program completion; In addition to the direct measurable program results summarized above, two primary lessons emerged from our work executing Energy IAP:; Validation and demonstration awards have an outsized, ‘tipping-point’ effect for startups looking to secure investments and strategic partnerships. An ecosystem approach is valuable, but an approach that evaluates the needs of individual companies and then draws from diverse ecosystem resources to fill them, is most valuable of all.

  3. EDITORIAL: Laser and plasma accelerators Laser and plasma accelerators

    Science.gov (United States)

    Bingham, Robert

    2009-02-01

    This special issue on laser and plasma accelerators illustrates the rapid advancement and diverse applications of laser and plasma accelerators. Plasma is an attractive medium for particle acceleration because of the high electric field it can sustain, with studies of acceleration processes remaining one of the most important areas of research in both laboratory and astrophysical plasmas. The rapid advance in laser and accelerator technology has led to the development of terawatt and petawatt laser systems with ultra-high intensities and short sub-picosecond pulses, which are used to generate wakefields in plasma. Recent successes include the demonstration by several groups in 2004 of quasi-monoenergetic electron beams by wakefields in the bubble regime with the GeV energy barrier being reached in 2006, and the energy doubling of the SLAC high-energy electron beam from 42 to 85 GeV. The electron beams generated by the laser plasma driven wakefields have good spatial quality with energies ranging from MeV to GeV. A unique feature is that they are ultra-short bunches with simulations showing that they can be as short as a few femtoseconds with low-energy spread, making these beams ideal for a variety of applications ranging from novel high-brightness radiation sources for medicine, material science and ultrafast time-resolved radiobiology or chemistry. Laser driven ion acceleration experiments have also made significant advances over the last few years with applications in laser fusion, nuclear physics and medicine. Attention is focused on the possibility of producing quasi-mono-energetic ions with energies ranging from hundreds of MeV to GeV per nucleon. New acceleration mechanisms are being studied, including ion acceleration from ultra-thin foils and direct laser acceleration. The application of wakefields or beat waves in other areas of science such as astrophysics and particle physics is beginning to take off, such as the study of cosmic accelerators considered

  4. Acceleration of polarized proton in high energy accelerators

    International Nuclear Information System (INIS)

    Lee, S.Y.

    1991-01-01

    In low to medium energy accelerators, betatron tune jumps and vertical orbit harmonic correction methods have been used to overcome the intrinsic and imperfection resonances. At high energy accelerators, snakes are needed to preserve polarization. The author analyzes the effects of snake resonances, snake imperfections, and overlapping resonances on spin depolarization. He discusses also results of recent snake experiments at the IUCF Cooler Ring. The snake can overcome various kinds of spin depolarization resonances. These experiments pointed out further that partial snake can be used to cure the imperfection resonances in low to medium energy accelerators

  5. "small ACCELERATORS" 24 May - 2 June 2005

    CERN Document Server

    2005-01-01

    CERN Accelerator School and Kernfysisch Versneller Instituut (KVI) Groningen, the Netherlands announce a course on "Small Accelerators", Hotel Golden Tulip Drenthe, Zeegse, the Netherlands, 24 May - 2 June 2005. This specialised course is dedicated to the physics and the main applications of small accelerators. The course will review the different accelerator types as well as their specificities in terms of accelerator physics.

  6. Accelerated cleanup risk reduction

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, R.B.; Aines, R.M.; Blake, R.G.; Copeland, A.B.; Newmark, R.L.; Tompson, A.F.B.

    1998-02-01

    There is no proven technology for remediating contaminant plume source regions in a heterogeneous subsurface. This project is an interdisciplinary effort to develop the requisite new technologies so that will be rapidly accepted by the remediation community. Our technology focus is hydrous pyrolysis/oxidation (HPO) which is a novel in situ thermal technique. We have expanded this core technology to leverage the action of steam injection and place an in situ microbial filter downstream to intercept and destroy the accelerated movement of contaminated groundwater. Most contaminant plume source regions, including the chlorinated solvent plume at LLNL, are in subsurface media characterized by a wide range in hydraulic conductivity. At LLNL, the main conduits for contaminant transport are buried stream channels composed of gravels and sands; these have a hydraulic conductivity in the range of 10{sup -1} to 10{sup -2} cm/s. Clay and silt units with a hydraulic conductivity of 10{sup -1} to 10{sup -6} cm/s bound these buried channels; these are barriers to groundwater movement and contain the highest contaminant concentrations in the source region. New remediation technologies are required because the current ones preferentially access the high conductivity units. HPO is an innovative process for the in situ destruction of contaminants in the entire subsurface. It operates by the injection of steam. We have demonstrated in laboratory experiments that many contaminants rapidly oxidize to harmless compounds at temperatures easily achieved by injecting steam, provided sufficient dissolved oxygen is present. One important challenge in a heterogeneous source region is getting heat, contaminants, and an oxidizing agent in the same place at the same time. We have used the NUFT computer program to simulate the cyclic injection of steam into a contaminated aquifer for design of a field demonstration. We used an 8 hour, steam/oxygen injection cycle followed by a 56 hour relaxation

  7. Acceleration of particles in plasmas

    CERN Multimedia

    CERN. Geneva

    2007-01-01

    The accelerating fields in radio-frequency accelerators are limited to roughly 100 MV/m due to material breakdown which occurs on the walls of the structure. In contrast, a plasma, being already ionized, can support electric fields in excess of 100 GV/m. Such high accelerating gradients hold the promise of compact particle accelerators. Plasma acceleration has been an emerging and fast growing field of research in the past two decades. In this series of lectures, we will review the principles of plasma acceleration. We will see how relativistic plasma waves can be excited using an ultra-intense laser or using a particle beam. We will see how these plasma waves can be used to accelerate electrons to high energy in short distances. Throughout the lectures, we will also review recent experimental results. Current laser-plasma experiments throughout the world have shown that monoenergetic electron beams from 100 MeV to 1 GeV can be obtained in distances ranging from the millimetre to the centimetre. Experiments a...

  8. Application of electron accelerator worldwide

    Energy Technology Data Exchange (ETDEWEB)

    Machi, Sueo [Japan Atomic Industrial Forum, Inc., Tokyo (Japan)

    2003-02-01

    Electron accelerator is an important radiation source for radiation technology, which covers broad fields such as industry, health care, food and environmental protection. There are about 1,000 electron accelerators for radiation processing worldwide. Electron accelerator has advantage over Co-60 irradiator in term of high dose rate and power, assurance of safety, and higher economic performance at larger volume of irradiation. Accelerator generating higher energy in the range of 10 MeV and high power electron beam is now commercially available. There is a trend to use high-energy electron accelerator replacing Co-60 in case of large through-put of medical products. Irradiated foods, in particular species, are on the commercial market in 35 countries. Electron accelerator is used efficiently and economically for production of new or modified polymeric materials through radiation-induced cross-linking, grafting and polymerization reaction. Another important application of electron beam is the curing of surface coatings in the manufacture of products. Electron accelerators of large capacity are used for cleaning exhaust gases in industrial scale. Economic feasibility studies of this electron beam process have shown that this technology is more cost effective than the conventional process. It should be noted that the conventional limestone process produce gypsum as a by-product, which cannot be used in some countries. By contrast, the by-product of the electron beam process is a valuable fertilizer. (Y. Tanaka)

  9. Teleportation with Multiple Accelerated Partners

    International Nuclear Information System (INIS)

    Sagheer, A.; Hamdoun, H.; Metwally, N.

    2015-01-01

    As the current revolution in communication is underway, quantum teleportation can increase the level of security in quantum communication applications. In this paper, we present a quantum teleportation procedure that capable to teleport either accelerated or non-accelerated information through different quantum channels. These quantum channels are based on accelerated multi-qubit states, where each qubit of each of these channels represents a partner. Namely, these states are the W state, Greenberger–Horne–Zeilinger (GHZ) state, and the GHZ-like state. Here, we show that the fidelity of teleporting accelerated information is higher than the fidelity of teleporting non-accelerated information, both through a quantum channel that is based on accelerated state. Also, the comparison among the performance of these three channels shows that the degree of fidelity depends on type of the used channel, type of the measurement, and value of the acceleration. The result of comparison concludes that teleporting information through channel that is based on the GHZ state is more robust than teleporting information through channels that are based on the other two states. For future work, the proposed procedure can be generalized later to achieve communication through a wider quantum network. (paper)

  10. Fixed-Target Electron Accelerators

    International Nuclear Information System (INIS)

    Brooks, William K.

    2001-01-01

    A tremendous amount of scientific insight has been garnered over the past half-century by using particle accelerators to study physical systems of sub-atomic dimensions. These giant instruments begin with particles at rest, then greatly increase their energy of motion, forming a narrow trajectory or beam of particles. In fixed-target accelerators, the particle beam impacts upon a stationary sample or target which contains or produces the sub-atomic system being studied. This is in distinction to colliders, where two beams are produced and are steered into each other so that their constituent particles can collide. The acceleration process always relies on the particle being accelerated having an electric charge; however, both the details of producing the beam and the classes of scientific investigations possible vary widely with the specific type of particle being accelerated. This article discusses fixed-target accelerators which produce beams of electrons, the lightest charged particle. As detailed in the report, the beam energy has a close connection with the size of the physical system studied. Here a useful unit of energy is a GeV, i.e., a giga electron-volt. (ne GeV, the energy an electron would have if accelerated through a billion volts, is equal to 1.6 x 10 -10 joules.) To study systems on a distance scale much smaller than an atomic nucleus requires beam energies ranging from a few GeV up to hundreds of GeV and more

  11. Is the Universe's Acceleration Eternal?

    Science.gov (United States)

    Bean, Rachel; Magueijo, Joao; Barrow, John

    2002-12-01

    We present a new interpretation of recent observations suggesting that the expansion of the Universe has recently started to accelerate. First we introduce a cosmological model with a minimally coupled quintessence field driven by a potential motivated by M-theory. We find that late-time acceleration does not have to lead to the usual predictions of perpetual acceleration. The model allows another broad class of scenarios in which today's acceleration is a transient phenomenon which is succeeded by a return to matter domination and decelerating expansion. Quintessence scenarios provide a simple explanation for the observed acceleration of the Universe. Yet, explaining why acceleration did not start a long time ago remains a challenge. The idea that the transition from radiation to matter domination played a dynamical role in triggering acceleration has been put forward in various guises. We, secondly, propose a simple dilaton-derived quintessence model in which temporary vacuum domination is naturally triggered by the radiation to matter transition. In this model Einstein's gravity is preserved but quintessence couples non-minimally to the cold dark matter, but not to "visible" matter. Such couplings have been attributed to the dilaton in the low-energy limit of string theory beyond tree level.

  12. Application of electron accelerator worldwide

    International Nuclear Information System (INIS)

    Machi, Sueo

    2003-01-01

    Electron accelerator is an important radiation source for radiation technology, which covers broad fields such as industry, health care, food and environmental protection. There are about 1,000 electron accelerators for radiation processing worldwide. Electron accelerator has advantage over Co-60 irradiator in term of high dose rate and power, assurance of safety, and higher economic performance at larger volume of irradiation. Accelerator generating higher energy in the range of 10 MeV and high power electron beam is now commercially available. There is a trend to use high-energy electron accelerator replacing Co-60 in case of large through-put of medical products. Irradiated foods, in particular species, are on the commercial market in 35 countries. Electron accelerator is used efficiently and economically for production of new or modified polymeric materials through radiation-induced cross-linking, grafting and polymerization reaction. Another important application of electron beam is the curing of surface coatings in the manufacture of products. Electron accelerators of large capacity are used for cleaning exhaust gases in industrial scale. Economic feasibility studies of this electron beam process have shown that this technology is more cost effective than the conventional process. It should be noted that the conventional limestone process produce gypsum as a by-product, which cannot be used in some countries. By contrast, the by-product of the electron beam process is a valuable fertilizer. (Y. Tanaka)

  13. CAS CERN Accelerator School second advanced accelerator physics course

    International Nuclear Information System (INIS)

    Turner, S.

    1989-01-01

    The advanced course on general accelerator physics given in West Berlin closely followed that organised by the CERN Accelerator School at Oxford in September 1985 and whose proceedings were published as CERN Yellow Report 87-03 (1987). However, certain subjects were treated in a different way, improved or extended, while some new ones were introduced and it is all of these which are included in the present proceedings. The lectures include particle-photon interactions, high-brilliance lattices and single/multiple Touschek effect, while the seminars are on the major accelerators presently under construction or proposed for the near future, applications of synchrotron radiation, free-electron lasers, cosmic accelerators and crystal beams. Also included are errata, and addenda to some of the lectures, of CERN 87-03. (orig.)

  14. 2014 CERN Accelerator Schools: Beam Loss and Accelerator Protection

    CERN Multimedia

    2014-01-01

    The US-CERN-JAPAN-RUSSIA Joint International Accelerator School is organising a course on Beam Loss and Accelerator Protection to be held in Newport Beach, California, USA from 5-14 November, 2014.    This school is intended for physicists and engineers who are or may be engaged in the design, construction, and/or operation of accelerators with high power photon or particle beams and/or accelerator sub-systems with large stored energy. Application deadlines are 15 August and 4 September. Further information on this Joint School can be found at: http://cas.web.cern.ch/cas/JAS/Newport%20Beach%202014/NPBadvert.html http://indico.cern.ch/event/287647/ http://uspas.fnal.gov/programs/JAS/JAS14.shtml

  15. Acceleration of polarized protons in the IHEP accelerator complex

    International Nuclear Information System (INIS)

    Anferov, V.A.; Ado, Yu.M.; Shoumkin, D.

    1995-01-01

    The paper considers possibility to accelerate polarized beam in the IHEP accelerator complex (including first stage of the UNK). The scheme of preserving beam polarization is described for all acceleration stages up to 400 GeV beam energy. Polarization and intensity of the polarized proton beam are estimated. The suggested scheme includes using two Siberian snakes in opposite straight sections of the UNK-1, where each snake consists of five dipole magnets. In the U-70 it is suggested to use one helical Siberian snake, which is turned on adiabatically at 10 GeV, and four pulsed quadrupoles. To incorporate the snake into the accelerator lattice it is proposed to make modification of one superperiod. This would make a 13 m long straight section. Spin depolarization in the Booster is avoided by decreasing the extraction energy to 0.9 GeV. Then no additional hardware is required in the Booster

  16. The Radiological Research Accelerator Facility

    International Nuclear Information System (INIS)

    Hall, E.J.; Marino, S.A.

    1990-07-01

    The Radiological Research Accelerator Facility (RARAF) is based on a 4-MV Van de Graaff accelerator, which is used to generate a variety of well-characterized radiation beams for research in radiobiology, radiological physics, and radiation chemistry. It is part of the Center for Radiological Research (CRR) -- formerly the Radiological Research Laboratory (RRL) -- of Columbia University, and its operation is supported as a National Facility by the US Department of Energy (DOE). Fifteen different experiments were run during these 12 months, approximately the same as the previous two years. Brief summaries of each experiment are included. Accelerator usage is summarized and development activities are discussed. 7 refs., 4 tabs

  17. PLASMA/ACCELERATORS: Working together

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    The quest for ever higher performances in particle accelerators has made accelerator and plasma experts get together. The status of this interdisciplinary effort was the topic of the April 87 issue of the IEEE Transactions on Plasma Science devoted to plasma-based high energy accelerators. At CERN, a plasma lens has been developed to collect divergent antiproton beams for the ACOL Antiproton Collector project. More generally, a plasma lens could replace magnetic horns and lithium lenses employed for the same purpose. In 1984, a collaboration started with the Universities of Erlangen and Naples, and the results and problems encountered were discussed in a Plasma Lens Workshop held at CERN in September 1986

  18. Experimental test accelerator (ETA) II

    International Nuclear Information System (INIS)

    Fessenden, T.J.; Atchison, W.L.; Birx, D.L.

    1981-01-01

    The Experimental Test Accelerator (ETA) is designed to produce a 10 kAmp electron beam at an energy of 4.5 MeV in 40 nsec pulses at an average rate of 2 pps. The accelerator also operates in bursts of 5 pulses spaced by as little as one millisec at an average rate of 5 pps. The machine is currently operating near 80% of its design values and has accumulated over 2.5 million pulses - mostly at a rate of one pps. The plasma cathode electron source, the remainder of the accelerator, and the operating characteristics of the machine are discussed

  19. Production of radioisotopes using accelerators

    International Nuclear Information System (INIS)

    Qaim, S.M.

    1990-01-01

    Accelerator produced radioisotopes find applications in many fields. Most of them are ideally suited for in-vivo studies of physiological functions. A brief review of various types of accelerators used for radioisotope production is given. The 'state of art' technology relevant to the production of radioisotopes is briefly discussed. Some of the recent advances in nuclear data measurements, target development, chemical processing and quality control are described. There appears to be a definite shift from multipurpose accelerators to dedicated machines, and greater emphasis is placed now on the production of radioisotopes with high radionuclidic purity by choosing a suitable nuclear reaction in a proper energy range. (author)

  20. Linear resonance acceleration of pellets

    International Nuclear Information System (INIS)

    Mills, R.G.

    1978-01-01

    A possible requirement for the acceleration of macroscopic pellets to velocities exceeding 10 4 meters per second implies the development of new apparatus. A satisfactory approach might be the linear resonance accelerator. Such apparatus would require the charging of pellets to very high values not yet demonstrated. The incompatibility of phase stability with radial stability in these machines may require abandoning phase stability and adopting feedback control of the accelerating voltage to accommodate statistical fluctuations in the charge to mass ratio of successive pellets

  1. A Phase Matching, Adiabatic Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Lemery, Francois [Hamburg U.; Flöttmann, Klaus [DESY; Kärtner, Franz [CFEL, Hamburg; Piot, Philippe [Northern Illinois U.

    2017-05-01

    Tabletop accelerators are a thing of the future. Reducing their size will require scaling down electromagnetic wavelengths; however, without correspondingly high field gradients, particles will be more susceptible to phase-slippage – especially at low energy. We investigate how an adiabatically-tapered dielectric-lined waveguide could maintain phase-matching between the accelerating mode and electron bunch. We benchmark our simple model with CST and implement it into ASTRA; finally we provide a first glimpse into the beam dynamics in a phase-matching accelerator.

  2. Hadron accelerators in cancer therapy

    International Nuclear Information System (INIS)

    Amaldi, U.; Silari, M.

    1997-01-01

    The application of hadron accelerators (protons and light ions) in cancer therapy is discussed. After a brief introduction on the rationale for the use of heavy charged particles in radiation therapy, a discussion is given on accelerator technology and beam delivery systems. Next, existing and planned facilities are briefly reviewed. The Italian Hadrontherapy Project (the largest project of this type in Europe) is then described, with reference to both the National Centre for Oncological Hadrontherapy and the design of two types of compact proton accelerators aimed at introducing proton therapy in a large number of hospitals. Finally, the radiation protection requirements are discussed. (author)

  3. Accelerator operation management using objects

    International Nuclear Information System (INIS)

    Nishimura, H.; Timossi, C.; Valdez, M.

    1995-01-01

    Conflicts over control of shared devices or resources in an accelerator control system, and problems that can occur due to applications performing conflicting operations, are usually resolved by accelerator operators. For these conflicts to be detected by the control system, a model of accelerator operation must be available to the system. The authors present a design for an operation management system addressing the issues of operations management using the language of Object-Oriented Design (OOD). A possible implementation using commercially available software tools is also presented

  4. Truck acceleration behavior study and acceleration lane length recommendations for metered on-ramps

    OpenAIRE

    Yang, Guangchuan; Xu, Hao; Wang, Zhongren; Tian, Zong

    2016-01-01

    This paper investigated the actual truck acceleration capability at metered on-ramps. Truck acceleration performance data were collected through a video-based data collection method. A piecewise constant acceleration model was employed to capture truck acceleration characteristics. It was found that the existing acceleration length will affect truck drivers’ acceleration behavior. At the taper type ramp that has limited acceleration distance, acceleration profile indicated a decreasing trend ...

  5. SNEAP 80: symposium of Northeastern Accelerator personnel

    Energy Technology Data Exchange (ETDEWEB)

    Billen, J.H. (ed.)

    1980-01-01

    Reports of operations are presented for twenty-seven facilities, along with reports on accelerators in progress, ion sources, insulating gases, charging systems, stripping foils, accelerating tubes, and upgraded accelerator systems. (GHT)

  6. SNEAP 80: symposium of Northeastern Accelerator personnel

    International Nuclear Information System (INIS)

    Billen, J.H.

    1980-01-01

    Reports of operations are presented for twenty-seven facilities, along with reports on accelerators in progress, ion sources, insulating gases, charging systems, stripping foils, accelerating tubes, and upgraded accelerator systems

  7. Acceleration Modes and Transitions in Pulsed Plasma Accelerators

    Science.gov (United States)

    Polzin, Kurt A.; Greve, Christine M.

    2018-01-01

    Pulsed plasma accelerators typically operate by storing energy in a capacitor bank and then discharging this energy through a gas, ionizing and accelerating it through the Lorentz body force. Two plasma accelerator types employing this general scheme have typically been studied: the gas-fed pulsed plasma thruster and the quasi-steady magnetoplasmadynamic (MPD) accelerator. The gas-fed pulsed plasma accelerator is generally represented as a completely transient device discharging in approximately 1-10 microseconds. When the capacitor bank is discharged through the gas, a current sheet forms at the breech of the thruster and propagates forward under a j (current density) by B (magnetic field) body force, entraining propellant it encounters. This process is sometimes referred to as detonation-mode acceleration because the current sheet representation approximates that of a strong shock propagating through the gas. Acceleration of the initial current sheet ceases when either the current sheet reaches the end of the device and is ejected or when the current in the circuit reverses, striking a new current sheet at the breech and depriving the initial sheet of additional acceleration. In the quasi-steady MPD accelerator, the pulse is lengthened to approximately 1 millisecond or longer and maintained at an approximately constant level during discharge. The time over which the transient phenomena experienced during startup typically occur is short relative to the overall discharge time, which is now long enough for the plasma to assume a relatively steady-state configuration. The ionized gas flows through a stationary current channel in a manner that is sometimes referred to as the deflagration-mode of operation. The plasma experiences electromagnetic acceleration as it flows through the current channel towards the exit of the device. A device that had a short pulse length but appeared to operate in a plasma acceleration regime different from the gas-fed pulsed plasma

  8. Theoretical problems in accelerator physics

    International Nuclear Information System (INIS)

    Kroll, N.M.

    1993-01-01

    This report discusses the following topics in accelerator physics: radio frequency pulse compression and power transport; computational methods for the computer analysis of microwave components; persistent wakefields associated with waveguide damping of higher order modes; and photonic band gap cavities

  9. IGBT accelerated aging data set.

    Data.gov (United States)

    National Aeronautics and Space Administration — Preliminary data from thermal overstress accelerated aging using the aging and characterization system. The data set contains aging data from 6 devices, one device...

  10. Accelerator structure work for NLC

    International Nuclear Information System (INIS)

    Miller, R.H.; Adolphsen, C.; Bane, K.L.F.; Deruyter, H.; Farkas, Z.D.; Hoag, H.A.; Holtkamp, N.; Lavine, T.; Loew, G.A.; Nelson, E.M.; Palmer, R.B.; Paterson, J.M.; Ruth, R.D.; Thompson, K.A.; Vlieks, A.; Wang, J.W.; Wilson, P.B.; Gluckstern, R.; Ko, K.; Kroll, N.; California Univ., San Diego, La Jolla, CA

    1992-07-01

    The NLC design achieves high luminosity with multiple bunches in each RF pulse. Acceleration of a train of bunches without emittance growth requires control of long range dipole wakefields. SLAC is pursuing a structure design which suppresses the effect of wakefields by varying the physical dimensions of successive cells of the disk-loaded traveling wave structure in a manner which spreads the frequencies of the higher mode while retaining the synchronism between the electrons and the accelerating mode. The wakefields of structures incorporating higher mode detuning have been measured at the Accelerator Test Facility at Argonne. Mechanical design and brazing techniques which avoid getting brazing alloy into the interior of the accelerator are being studied. A test facility for high-power testing of these structures is complete and high power testing has begun

  11. Linear accelerator for tritium production

    International Nuclear Information System (INIS)

    Garnett, R.W.; Billen, J.H.; Chan, K.C.D.

    1995-01-01

    For many years now, Los Alamos National Laboratory has been working to develop a conceptual design of a facility for accelerator production of tritium (API). The APT accelerator will produce high energy protons which will bombard a heavy metal target, resulting in the production of large numbers of spallation neutrons. These neutrons will be captured by a low-Z target to produce tritium. This paper describes the latest design of a room-temperature, 1.0 GeV, 100 mA, cw proton accelerator for tritium production. The potential advantages of using superconducting cavities in the high-energy section of the linac are also discussed and a comparison is made with the baseline room-temperature accelerator

  12. 1988 linear accelerator conference proceedings

    International Nuclear Information System (INIS)

    1989-06-01

    This report contains papers presented at the 1988 Linear Accelerator Conference. A few topics covered are beam dynamics; beam transport; superconducting components; free electron lasers; ion sources; and klystron research

  13. Electron accelerators for radiation sterilization

    International Nuclear Information System (INIS)

    Zimek, Z.; Stanikowski, J.

    2007-01-01

    Presentation describes briefly different types of the electron accelerators applicable for the radiosterilization of food and/or medical materials. LAE 10 source operating in the Institute of Nuclear Chemistry and Technology (Warsaw, Poland) is described in details

  14. Fate of an accelerating universe

    International Nuclear Information System (INIS)

    Gu, J.-A.; Hwang, W-Y. P.

    2006-01-01

    The presently accelerating universe may keep accelerating forever, eventually run into the event horizon problem, and thus be in conflict with the superstring idea. On the other hand, the current accelerating phase as well as the fate of the universe may be swayed by a negative cosmological constant, which dictates a big crunch. Based on the current observational data, in this paper we investigate how large the magnitude of a negative cosmological constant is allowed to be. In addition, for distinguishing the sign of the cosmological constant via observations, we point out that a measure of the evolution of the dark energy equation-of-state may be a good discriminator. Hopefully future observations will provide much more detailed information about dark energy and thereby indicate the sign of the cosmological constant as well as the fate of the presently accelerating universe

  15. High temperature superconductor accelerator magnets

    NARCIS (Netherlands)

    van Nugteren, J.

    2016-01-01

    For future particle accelerators bending dipoles are considered with magnetic fields exceeding 20T. This can only be achieved using high temperature superconductors (HTS). These exhibit different properties from classical low temperature superconductors and still require significant research and

  16. Advanced Superconducting Test Accelerator (ASTA)

    Data.gov (United States)

    Federal Laboratory Consortium — The Advanced Superconducting Test Accelerator (ASTA) facility will be based on upgrades to the existing NML pulsed SRF facility. ASTA is envisioned to contain 3 to 6...

  17. Accelerator and fusion research division

    International Nuclear Information System (INIS)

    1992-12-01

    This report contains brief discussions on research topics in the following area: Heavy-Ion Fusion Accelerator Research; Magnetic Fusion Energy; Advanced Light Source; Center for Beam Physics; Superconducting Magnets; and Bevalac Operations

  18. Future dedicated medical ion accelerator

    International Nuclear Information System (INIS)

    Gough, R.A.; Alonso, J.R.; Elioff, T.; Grunder, H.

    1980-01-01

    Current biomedical studies and clinical trials with charged particles rely on accelerators that were designed for physics research. In contrast, the design and construction of particle accelerators designed specifically to meet medical requirements would result in cost-effective and highly reliable accelerators suitable for routine, hospital-based, clinical service with modest operations and maintenance crews. The experience of the LBL 184-Inch Synchrocyclotron, which is dedicated for medical use, indicates that extremely high facility availability can be readily achieved when operational standards are optimized for reliability. Therefore, we are in the process of submitting to the National Cancer Institute a three-year design proposal (for fiscal years 1981 to 1983) to perform the requisite research and development and to generate plans and realistic cost estimates for a dedicated heavy-ion medical accelerator suitable for a hospital-based environment

  19. Particle accelerator; the Universe machine

    CERN Multimedia

    Yurkewicz, Katie

    2008-01-01

    "In summer 2008, scientists will switch on one of the largest machines in the world to search for the smallest of particle. CERN's Large Hadron Collider particle accelerator has the potential to chagne our understanding of the Universe."

  20. Argonne Wakefield Accelerator Update '92

    International Nuclear Information System (INIS)

    Rosing, M.; Balka, L.; Chojnacki, E.; Gai, W.; Ho, C.; Konecny, R.; Power, J.; Schoessow, P.; Simpson, J.

    1992-01-01

    The Argonne Wakefield Accelerator (AWA) is an experiment designed to test various ideas related to wakefield technology. Construction is now underway for a 100 nC electron beam in December of 1992. This report updates this progress

  1. Prototype of industrial electrons accelerator

    International Nuclear Information System (INIS)

    Lopez, V.H.; Valdovinos, A.M.

    1992-01-01

    The interest and the necessity of Mexico's industry in the use of irradiation process has been increased in the last years. As examples are the irradiation of combustion gases (elimination of NO x and SO 2 ) and the polymer cross-linking between others. At present time at least twelve enterprises require immediately of them which have been contacted by electron accelerators suppliers of foreign countries. The first project step consisted in to identify the electrons accelerator type that in can be constructed in Mexico with the major number of possible equipment, instruments, components and acquisition materials local and useful for the major number of users. the characteristics of the accelerator prototype are: accelerator type transformer with multiple secondary insulated and rectifier circuits with a potential of 0.8 MV of voltage, the second step it consisted in an economic study that permitted to demonstrate the economic feasibility of its construction. (Author)

  2. Particle acceleration by plasma waves

    International Nuclear Information System (INIS)

    Joshi, C.

    2006-01-01

    In an advanced particle accelerator particles are driven near by light velocity through ionized gas. Such plasma devices are compact, cost efficient and usable in many fields. Examples are given in detail. (GL)

  3. Accelerating and rotating black holes

    International Nuclear Information System (INIS)

    Griffiths, J B; Podolsky, J

    2005-01-01

    An exact solution of Einstein's equations which represents a pair of accelerating and rotating black holes (a generalized form of the spinning C-metric) is presented. The starting point is a form of the Plebanski-Demianski metric which, in addition to the usual parameters, explicitly includes parameters which describe the acceleration and angular velocity of the sources. This is transformed to a form which explicitly contains the known special cases for either rotating or accelerating black holes. Electromagnetic charges and a NUT parameter are included, the relation between the NUT parameter l and the Plebanski-Demianski parameter n is given, and the physical meaning of all parameters is clarified. The possibility of finding an accelerating NUT solution is also discussed

  4. Technology of superconducting accelerator dipoles

    International Nuclear Information System (INIS)

    Hassenzahl, W.V.; Meuser, R.B.; Taylor, C.

    1983-06-01

    We discuss accelerator dipoles and their characteristics. Other types of magnets, in particular bubble chamber magnets have been quite successful. Their performance is based on cryogenic stability which is addressed only briefly in this chapter. This type of stability is not available to the accelerator designer because of the large quantities of copper or other stabilizer that would reduce the current density in the windings to an unacceptably low value

  5. Guassian beams and electron acceleration

    International Nuclear Information System (INIS)

    Collins, M.; Castillo, R.; Osman, F.; Evans, P.; Stiat-Gardener, T.; Hora, H.

    2000-01-01

    Full text: A guassian solution to the free space wave equation to fourth order is derived using the Fourier transform method. Higher order solutions can be generated, as needed, using the convolution method. These results are used to investigate the acceleration of an electron in a laser field. The acceleration is determined if energy is transferred to a relativistic electron, this energy transfer can be determined by calculating the change in the potential of the electron

  6. Particle accelerators and scientific culture

    International Nuclear Information System (INIS)

    Amaldi, U.

    1979-01-01

    A historical review of fifty years of physics around particle accelerators, from the first nuclear reactions produced by beams of artificially accelerated particles to the large multinational projects now under discussion. The aim is to show how our description of natural phenomena has been shaped by advances in theoretical understanding, the development of new techniques, and the characters of men. Large use has been made of quotations from many of the scientists involved. (Auth.)

  7. Proposed Lucas Heights tandem accelerator

    International Nuclear Information System (INIS)

    1985-01-01

    An 8 million volt tandem accelerator (LHTA - Lucas Heights Tandem Accelerator) is proposed to be installed at the Australian Atomic Energy Commission's Lucas Heights Research Laboratories. The new facility is expected to cost $6 million and will have applications such as ultrasensitive trace element analysis for management of groundwater resources, salinity in soil, soil erosion and Antarctic research. Applied physics applications include nuclear safeguards, energy sources, study of material surfaces, archaeology, archaeometry and occupational health

  8. Towards stable acceleration in LINACS

    CERN Document Server

    Dubrovskiy, A D

    2014-01-01

    Ultra-stable and -reproducible high-energy particle beams with short bunches are needed in novel linear accelerators and, in particular, in the Compact Linear Collider CLIC. A passive beam phase stabilization system based on a bunch compression with a negative transfer matrix element R56 and acceleration at a positive off-crest phase is proposed. The motivation and expected advantages of the proposed scheme are outlined.

  9. Particle accelerators and scientific culture

    International Nuclear Information System (INIS)

    Amaldi, U.

    1979-01-01

    A historical review of fifty years of physics around particle accelerators, from the first nuclear reactions produced by beams of artificially accelerated particles to the large multinational projects now under discussion. The aim is to show how the description of natural phenomena has been shaped by advances in theoretical understanding, the development of new techniques, and the characters of men. Large use has been made of quotations from many of the scientists involved. (Auth.)

  10. Accelerator physics and modeling: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Parsa, Z. [ed.

    1991-12-31

    This report contains papers on the following topics: Physics of high brightness beams; radio frequency beam conditioner for fast-wave free-electron generators of coherent radiation; wake-field and space-charge effects on high brightness beams. Calculations and measured results for BNL-ATF; non-linear orbit theory and accelerator design; general problems of modeling for accelerators; development and application of dispersive soft ferrite models for time-domain simulation; and bunch lengthening in the SLC damping rings.

  11. Accelerator physics and modeling: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Parsa, Z. (ed.)

    1991-01-01

    This report contains papers on the following topics: Physics of high brightness beams; radio frequency beam conditioner for fast-wave free-electron generators of coherent radiation; wake-field and space-charge effects on high brightness beams. Calculations and measured results for BNL-ATF; non-linear orbit theory and accelerator design; general problems of modeling for accelerators; development and application of dispersive soft ferrite models for time-domain simulation; and bunch lengthening in the SLC damping rings.

  12. Industrial applications of electron beam accelerators

    International Nuclear Information System (INIS)

    Braid, W.G. Jr.

    1976-01-01

    The use of electron beam accelerators for crosslinking polyolefins for shrinking food packaging is discussed. Irradiation procedures, accelerator characteristics, and industrial operations are described

  13. Accelerator Physics Section progress report

    International Nuclear Information System (INIS)

    Coote, G.E.

    1986-05-01

    This report summarizes the work of the Accelerator Physics Section of the Institute of Nuclear Sciences during the period January-December 1985. Applications of the EN-tandem accelerator included 13 N production for tracer experiments in plants and animals, hydrogen profiling with a 19 F beam and direct detection of heavy ions with a surface barrier detector. Preparations for accelerator mass spectrometry continued steadily, with the commissioning of the pulsed EHT supply which selects the isotope to be accelerated, routine detection of 14 C ions, and completion of a sputter ion source with an eight position target wheel. It was shown that the hydrogen content of a material could be derived from a simultaneous measurement of the transmission of neutrons and gamma rays from a neutron source or accelerator target. The 11 CO 2 produced at the 3 MV accelerator was used in two studies of translocation in a large number of plant species: the effects of small quantities of SO 2 in the air, and the effect of cooling a short length of the stem. The nuclear microprobe was applied to studies of carbon pickup during welding of stainless steel, determination of trace elements in soil and vegetation and the measurement of sodium depth profiles in obsidian - in particular the effect of rastering the incident proton beams

  14. Accelerated cleanup risk reduction

    International Nuclear Information System (INIS)

    Knapp, R.B.; Aines, R.M.; Blake, R.G.; Copeland, A.B.; Newmark, R.L.; Tompson, A.F.B.

    1998-01-01

    There is no proven technology for remediating contaminant plume source regions in a heterogeneous subsurface. This project is an interdisciplinary effort to develop the requisite new technologies so that will be rapidly accepted by the remediation community. Our technology focus is hydrous pyrolysis/oxidation (HPO) which is a novel in situ thermal technique. We have expanded this core technology to leverage the action of steam injection and place an in situ microbial filter downstream to intercept and destroy the accelerated movement of contaminated groundwater. Most contaminant plume source regions, including the chlorinated solvent plume at LLNL, are in subsurface media characterized by a wide range in hydraulic conductivity. At LLNL, the main conduits for contaminant transport are buried stream channels composed of gravels and sands; these have a hydraulic conductivity in the range of 10 -1 to 10 -2 cm/s. Clay and silt units with a hydraulic conductivity of 10 -1 to 10 -6 cm/s bound these buried channels; these are barriers to groundwater movement and contain the highest contaminant concentrations in the source region. New remediation technologies are required because the current ones preferentially access the high conductivity units. HPO is an innovative process for the in situ destruction of contaminants in the entire subsurface. It operates by the injection of steam. We have demonstrated in laboratory experiments that many contaminants rapidly oxidize to harmless compounds at temperatures easily achieved by injecting steam, provided sufficient dissolved oxygen is present. One important challenge in a heterogeneous source region is getting heat, contaminants, and an oxidizing agent in the same place at the same time. We have used the NUFT computer program to simulate the cyclic injection of steam into a contaminated aquifer for design of a field demonstration. We used an 8 hour, steam/oxygen injection cycle followed by a 56 hour relaxation period in which the

  15. Dusty-Plasma Particle Accelerator

    Science.gov (United States)

    Foster, John E.

    2005-01-01

    A dusty-plasma apparatus is being investigated as means of accelerating nanometer- and micrometer-sized particles. Applications for the dusty-plasma particle accelerators fall into two classes: Simulation of a variety of rapidly moving dust particles and micrometeoroids in outer-space environments that include micrometeoroid streams, comet tails, planetary rings, and nebulae and Deposition or implantation of nanoparticles on substrates for diverse industrial purposes that could include hardening, increasing thermal insulation, altering optical properties, and/or increasing permittivities of substrate materials. Relative to prior apparatuses used for similar applications, dusty-plasma particle accelerators offer such potential advantages as smaller size, lower cost, less complexity, and increased particle flux densities. A dusty-plasma particle accelerator exploits the fact that an isolated particle immersed in plasma acquires a net electric charge that depends on the relative mobilities of electrons and ions. Typically, a particle that is immersed in a low-temperature, partially ionized gas, wherein the average kinetic energy of electrons exceeds that of ions, causes the particle to become negatively charged. The particle can then be accelerated by applying an appropriate electric field. A dusty-plasma particle accelerator (see figure) includes a plasma source such as a radio-frequency induction discharge apparatus containing (1) a shallow cup with a biasable electrode to hold the particles to be accelerated and (2) a holder for the substrate on which the particles are to impinge. Depending on the specific design, a pair of electrostatic-acceleration grids between the substrate and discharge plasma can be used to both collimate and further accelerate particles exiting the particle holder. Once exposed to the discharge plasma, the particles in the cup quickly acquire a negative charge. Application of a negative voltage pulse to the biasable electrode results in the

  16. Resent advance in electron linear accelerators

    International Nuclear Information System (INIS)

    Takeda, Seishi; Tsumori, Kunihiko; Takamuku, Setsuo; Okada, Toichi; Hayashi, Koichiro; Kawanishi, Masaharu

    1986-01-01

    In recently constructed electron linear accelerators, there has been remarkable advance both in acceleration of a high-current single bunch electron beam for radiation research and in generation of high accelerating gradient for high energy accelerators. The ISIR single bunch electron linear accelerator has been modified an injector to increase a high-current single bunch charge up to 67 nC, which is ten times greater than the single bunch charge expected in early stage of construction. The linear collider projects require a high accelerating gradient of the order of 100 MeV/m in the linear accelerators. High-current and high-gradient linear accelerators make it possible to obtain high-energy electron beam with small-scale linear accelerators. The advance in linear accelerators stimulates the applications of linear accelerators not only to fundamental research of science but also to industrial uses. (author)

  17. Feasibility of accelerator driven system

    International Nuclear Information System (INIS)

    Lee, Tae Yeon; Lee, Hee Seok

    2012-01-01

    Currently, there are two challenges or threats to the Nuclear Power community. One is the anti nuclear mood after the East Japan earthquake one year ago and the subsequent nuclear disaster. We are not sure at this moment when this mood will be eased. The other threat is the recent shale gas boom (or may be called even a revolution) that began in UA and will be spread to all over the world soon. This second threat is just as serious as the first one. Nuclear power will not receive the attention it used to a few years ago. Economically, it may be ok, however, it will be a disaster to the future of mankind, because shale gas will never solve the problem of global warming. Until now, nuclear power is the only alternative to the fossil energy to save the world. That is why the nuclear power community needs a breakthrough and it is obvious what kind of breakthrough is needed. World needs a safer and cleaner nuclear power plant. A nuclear power plant that will not cause a disaster and that will produce radio toxic nuclear waste as small as possible. At the moment, the closest system is the accelerator driven system (ADS). First of all, it is safer in a disaster such as an earthquake, because the deriving accelerator stops immediately by the earthquake. It also minimizes the nuclear waste problem by reducing the amount of the toxic waste and shortening their half lifetime to only a few hundred years. Finally, it solves the Uranium reserve problem because it can use Thorium as its fuel. The Thorium reserve is much larger than that of Uranium. Although the idea of ADS was proposed long time ago, it has not been utilized yet first by technical difficulty of accelerator. The accelerator based system needs 1 GeV, 10 MW power proton beam, which is an unprecedentedly high power. The most powerful 1 GeV proton linear accelerator is the Spallation Neutron Source, USA, which operates now at the power of 1.5 MW with the length of 350 m. A conventional linear accelerator would need

  18. Accelerator and electrodynamics capability review

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Kevin W [Los Alamos National Laboratory

    2010-01-01

    Los Alamos National Laboratory (LANL) uses capability reviews to assess the science, technology and engineering (STE) quality and institutional integration and to advise Laboratory Management on the current and future health of the STE. Capability reviews address the STE integration that LANL uses to meet mission requirements. The Capability Review Committees serve a dual role of providing assessment of the Laboratory's technical contributions and integration towards its missions and providing advice to Laboratory Management. The assessments and advice are documented in reports prepared by the Capability Review Committees that are delivered to the Director and to the Principal Associate Director for Science, Technology and Engineering (PADSTE). Laboratory Management will use this report for STE assessment and planning. LANL has defined fifteen STE capabilities. Electrodynamics and Accelerators is one of the seven STE capabilities that LANL Management (Director, PADSTE, technical Associate Directors) has identified for review in Fiscal Year (FY) 2010. Accelerators and electrodynamics at LANL comprise a blend of large-scale facilities and innovative small-scale research with a growing focus on national security applications. This review is organized into five topical areas: (1) Free Electron Lasers; (2) Linear Accelerator Science and Technology; (3) Advanced Electromagnetics; (4) Next Generation Accelerator Concepts; and (5) National Security Accelerator Applications. The focus is on innovative technology with an emphasis on applications relevant to Laboratory mission. The role of Laboratory Directed Research and Development (LDRD) in support of accelerators/electrodynamics will be discussed. The review provides an opportunity for interaction with early career staff. Program sponsors and customers will provide their input on the value of the accelerator and electrodynamics capability to the Laboratory mission.

  19. CAS Accelerator Physics (RF for Accelerators) in Denmark

    CERN Multimedia

    Barbara Strasser

    2010-01-01

    The CERN Accelerator School (CAS) and Aarhus University jointly organised a specialised course on RF for Accelerators, at the Ebeltoft Strand Hotel, Denmark from 8 to 17 June 2010.   Caption The challenging programme focused on the introduction of the underlying theory, the study and the performance of the different components involved in RF systems, the RF gymnastics and RF measurements and diagnostics. This academic part was supplemented with three afternoons dedicated to practical hands-on exercises. The school was very successful, with 100 participants representing 25 nationalities. Feedback from the participants was extremely positive, praising the expertise and enthusiasm of the lecturers, as well as the high standard and excellent quality of their lectures. In addition to the academic programme, the participants were able to visit a small industrial exhibition organised by Aarhus University and take part in a one-day excursion consisting of a visit of the accelerators operated ...

  20. CAS CERN Accelerator School: Fourth general accelerator physics course

    International Nuclear Information System (INIS)

    Turner, S.

    1991-01-01

    The fourth CERN Accelerator School (CAS) basic course on General Accelerator Physics was given at KFA, Juelich, from 17 to 28 September 1990. Its syllabus was based on the previous similar courses held at Gif-sur-Yvette in 1984, Aarhus 1986, and Salamanca 1988, and whose proceedings were published as CERN Reports 85-19, 87-10, and 89-05, respectively. However, certain topics were treated in a different way, improved or extended, while new subjects were introduced. All of these appear in the present proceedings, which include lectures or seminars on the history and applications of accelerators, phase space and emittance, chromaticity, beam-beam effects, synchrotron radiation, radiation damping, tune measurement, transition, electron cooling, the designs of superconducting magnets, ring lattices, conventional RF cavities and ring RF systems, and an introduction to cyclotrons. (orig.)

  1. CAS CERN Accelerator School third general accelerator physics course

    International Nuclear Information System (INIS)

    Turner, S.

    1989-01-01

    The general course on accelerator physics given in Salamanca, Spain, closely followed those organised by the CERN Accelerator School at Gif-sur-Yvette, Paris in 1984, and at Aarhus, Denmark in 1986 and whose proceedings were published as CERN Yellow Reports 85-19 (1985) and 87-10 (1987) respectively. However, certain topics were treated in a different way, improved or extended, while some new ones were introduced and it is all of these which are included in the present proceedings. The lectures include beam-cooling concepts, Liouville's theorem and emittance, emittance dilution in transfer lines, weak-betatron coupling, diagnostics, while the seminars are on positron and electron sources, linac structures and the LEP L3 experiment, together with industrial aspects of particle accelerators. Also included are errata and addenda to the Yellow Reports mentioned above. (orig.)

  2. CAS CERN Accelerator School. Third advanced accelerator physics course

    International Nuclear Information System (INIS)

    Turner, S.

    1990-01-01

    The third version of the CERN Accelerator School's (CAS) advanced course on General Accelerator Physics was given at Uppsala University from 18-29 September, 1989. Its syllabus was based on the previous courses held in Oxford, 1985 and Berlin, 1987 whose proceedings were published as CERN Yellow Reports 87-03 and 89-01 respectively. However, the opportunity was taken to emphasize the physics of small accelerators and storage rings, to present some topics in new ways, and to introduce new seminars. Thus the lectures contained in the present volume include chromaticity, dynamic aperture, kinetic theory, Landau damping, ion-trapping, Schottky noise, laser cooling and small ring lattice problems while the seminars include interpretation of numerical tracking, internal targets and living with radiation. (orig.)

  3. The Accelerator Markup Language and the Universal Accelerator Parser

    Energy Technology Data Exchange (ETDEWEB)

    Sagan, D.; Forster, M.; /Cornell U., LNS; Bates, D.A.; /LBL, Berkeley; Wolski, A.; /Liverpool U. /Cockcroft Inst. Accel. Sci. Tech.; Schmidt, F.; /CERN; Walker, N.J.; /DESY; Larrieu, T.; Roblin, Y.; /Jefferson Lab; Pelaia, T.; /Oak Ridge; Tenenbaum, P.; Woodley, M.; /SLAC; Reiche, S.; /UCLA

    2006-10-06

    A major obstacle to collaboration on accelerator projects has been the sharing of lattice description files between modeling codes. To address this problem, a lattice description format called Accelerator Markup Language (AML) has been created. AML is based upon the standard eXtensible Markup Language (XML) format; this provides the flexibility for AML to be easily extended to satisfy changing requirements. In conjunction with AML, a software library, called the Universal Accelerator Parser (UAP), is being developed to speed the integration of AML into any program. The UAP is structured to make it relatively straightforward (by giving appropriate specifications) to read and write lattice files in any format. This will allow programs that use the UAP code to read a variety of different file formats. Additionally, this will greatly simplify conversion of files from one format to another. Currently, besides AML, the UAP supports the MAD lattice format.

  4. Optimization of negative ion accelerators

    International Nuclear Information System (INIS)

    Pamela, J.

    1991-01-01

    We have started to study negative ion extraction and acceleration systems in view of designing a 1 MeV D - accelerator. This study is being made with a two-Dimensional code that has been specifically developed in our laboratory and validated by comparison to three sets of experimental data. We believe that the criteria for negative ion accelerator design optimization should be: (i) to provide the best optics; (ii) to reduce the power load on the extraction grid; (iii) to allow operation with low electric fields in order to reduce the problem of breakdowns. We show some results of optics calculations performed for two systems that will be operational in the next months: the CEA-JAERI collaboration at Cadarache and the european DRAGON experiment at Culham. Extrapolations to higher energies of 500 to 1100 keV have also been conducted. All results indicate that the overall accelerator length, whatever be the number of gaps, is constrained by space charge effects (Child-Langmuir). We have combined this constraint with high-voltage hold-off empirical laws. As a result, it appears that accelerating 10 mA/cm 2 of D - at 1 MeV with good optics, as required for NET or ITER, is close to the expected limit of high-voltage hold-off

  5. Metabolic acceleration in Mediterranean Perciformes

    Science.gov (United States)

    Lika, Konstadia; Kooijman, Sebastiaan A. L. M.; Papandroulakis, Nikos

    2014-11-01

    Larval stages are considered the most critical of fish development. During a very short period of time (2 to 3 months), larvae undergo major morphoanatomical and functional changes in order to transform into juveniles while remaining functioning (developing, eating, surviving). Depending on species and environmental conditions, patterns in larval development may vary. We study the patterns of larval development for nine fish species of Perciformes reared under aquaculture conditions and compare them in terms of species-specific parameters derived from DEB theory. We extended the standard DEB model to include metabolic acceleration during the larval period, where maximum specific assimilation and energy conductance increase with length between birth and metabolic metamorphosis. Metabolic acceleration has as a consequence that larvae initially grow slower than juveniles and adults. Our results indicate that the species with higher acceleration have lower growth rates at birth and they also suggest that metabolic acceleration is related to spawning season. High metabolic acceleration of demersal species is associated with summer-autumn spawning in the Mediterranean, where temperature is high and food availability is low.

  6. ETA-II accelerator upgrades

    International Nuclear Information System (INIS)

    Nilson, D.G.; Deadrick, F.J.; Hibbs, S.M.; Sampayan, S.E.; Petersen, D.E.

    1991-09-01

    We discuss recent improvements to the ETA-II linear induction electron accelerator. The accelerator's cells have been carefully reconditioned to raise the maximum accelerating gap voltage from approximately 100 kV to 125 kV. Insulators of Rexolite plastic in a new ''zero-gap'' arrangement replaced the alumina originals after several alternative materials were investigated. A new multi-cable current feed system will be used to eliminate pulse reflection interactions encountered in earlier experiments. Improved alignment fixtures have been installed to help minimize beam perturbation due to poorly aligned intercell magnets between 10-cell groups. A stretched wire alignment technique (SWAT) has been utilized to enhance overall magnetic alignment, and to characterize irreducible alignment errors. These changes are in conjunction with an expansion of the accelerator from a 20-cell to a 60-cell configuration. When completed, the upgraded accelerator is expected to deliver 2.5 kA of electron beam current at 7.5 MeV in bursts of up to fifty 70-ns pulses at a 5-kHz repetition rate. A 5.5-meter-long wiggler will convert the energy into 3-GW microwave pulses at 140 GHz for plasma heating experiments in the Microwave Tokamak Experiment (MTX)

  7. Beam dynamics for induction accelerators

    International Nuclear Information System (INIS)

    Lee, Edward P.

    2014-01-01

    An induction linac uses pulsed power that is applied directly, without any intervening resonant cavities, to accelerate a charged particle pulse. This approach can accommodate a large multiple-beam focusing lattice capable of transporting a large total beam current with a long pulse duration, which may be compressed while accelerating as well as afterward. The mean accelerating gradient is relatively low (less than about 1.5 MV/m), but the potential efficiency of energy transfer can be large up to about 50%. A multiple-beam induction linac is therefore a natural candidate accelerator for a heavy ion fusion (HIF) driver. However, the accelerated beams must meet stringent requirements on occupied phase space volume in order to be focused accurately and with small radius onto the fusion target. Dynamical considerations in the beam injector and linac, as well as in the final compression, final focus, and the fusion chamber, determine the quality of the driver beams as they approach the target. Requirements and tolerances derived from beam dynamics strongly influence the linac configuration and component design. After a summary of dynamical considerations, two major topics are addressed here: transportable current limits, which determine the choice of focal system for the linac, and longitudinal control of the beams, which are potentially destabilized by their interaction with the pulsed power system

  8. Guidelines for Developing an Academic Acceleration Policy

    Science.gov (United States)

    Colangelo, Nicholas; Assouline, Susan G.; Marron, Maureen A.; Castellano, Jaime A.; Clinkenbeard, Pamela R.; Rogers, Karen; Calvert, Eric; Malek, Rosanne; Smith, Donnajo

    2010-01-01

    As an educational intervention, acceleration is decidedly effective for high-ability students. The research support for acceleration that has accumulated over many decades is robust and consistent and allows us to confidently state that carefully planned acceleration decisions are successful. Both grade-based and content-based acceleration are…

  9. Accelerator Technology Division annual report, FY 1989

    International Nuclear Information System (INIS)

    1990-06-01

    This paper discusses: accelerator physics and special projects; experiments and injectors; magnetic optics and beam diagnostics; accelerator design and engineering; radio-frequency technology; accelerator theory and simulation; free-electron laser technology; accelerator controls and automation; and high power microwave sources and effects

  10. Superconducting linear accelerator system for NSC

    Indian Academy of Sciences (India)

    This paper reports the construction of a superconducting linear accelerator as a booster to the 15 UD Pelletron accelerator at Nuclear Science Centre, New Delhi. The LINAC will use superconducting niobium quarter wave resonators as the accelerating element. Construction of the linear accelerator has progressed ...

  11. Particle acceleration in near critical density plasma

    International Nuclear Information System (INIS)

    Gu, Y.J.; Kong, Q.; Kawata, S.; Izumiyama, T.; Nagashima, T.

    2013-01-01

    Charged particle acceleration schemes driven by ultra intense laser and near critical density plasma interactions are presented. They include electron acceleration in a plasma channel, ion acceleration by the Coulomb explosion and high energy electron beam driven ion acceleration. It is found that under the near critical density plasma both ions and electrons are accelerated with a high acceleration gradient. The electron beam containing a large charge quantity is accelerated well with 23 GeV/cm. The collimated ion bunch reaches 1 GeV. The investigations and discussions are based on 2.5D PIC (particle-in-cell) simulations. (author)

  12. Ultra-high vacuum photoelectron linear accelerator

    Science.gov (United States)

    Yu, David U.L.; Luo, Yan

    2013-07-16

    An rf linear accelerator for producing an electron beam. The outer wall of the rf cavity of said linear accelerator being perforated to allow gas inside said rf cavity to flow to a pressure chamber surrounding said rf cavity and having means of ultra high vacuum pumping of the cathode of said rf linear accelerator. Said rf linear accelerator is used to accelerate polarized or unpolarized electrons produced by a photocathode, or to accelerate thermally heated electrons produced by a thermionic cathode, or to accelerate rf heated field emission electrons produced by a field emission cathode.

  13. Acceleration mapping on Consort 5

    Science.gov (United States)

    Naumann, Robert J.

    1994-09-01

    The Consort 5 rocket carrying a set of commercial low-gravity experiments experienced a significant side thrust from an apparent burn-through of the second-stage motor just prior to cut-off. The resulting angular momentum could not be removed by the attitude rate control system, thus the payload was left in an uncontrollable rocking/tumbling mode. Although the primary low-gravity emphasis mission requirements could not be met, it was hoped that some science could be salvaged by mapping the acceleration field over the vehicle so that each investigator could correlate his or her results with the acceleration environment at his or her experiment location. This required some detective work to obtain the body rates and moment of inertia ratios required to solve the full set of Euler equations for a tri-axial rigid body. The techniques for acceleration mapping described in this paper may be applicable to other low-gravity emphasis missions.

  14. A Multibunch Plasma Wakefield Accelerator

    CERN Document Server

    Kallos, Efthymios; Ben-Zvi, Ilan; Katsouleas, Thomas C; Kimura, Wayne D; Kusche, Karl; Muggli, Patric; Pavlishin, Igor; Pogorelsky, Igor; Yakimenko, Vitaly; Zhou, Feng

    2005-01-01

    We investigate a plasma wakefield acceleration scheme where a train of electron microbunches feeds into a high density plasma. When the microbunch train enters such a plasma that has a corresponding plasma wavelength equal to the microbunch separation distance, a strong wakefield is expected to be resonantly driven to an amplitude that is at least one order of magnitude higher than that using an unbunched beam. PIC simulations have been performed using the beamline parameters of the Brookhaven National Laboratory Accelerator Test Facility operating in the configuration of the STELLA inverse free electron laser (IFEL) experiment. A 65 MeV electron beam is modulated by a 10.6 um CO2 laser beam via an IFEL interaction. This produces a train of ~90 microbunches separated by the laser wavelength. In this paper, we present both a simple theoretical treatment and simulation results that demonstrate promising results for the multibunch technique as a plasma-based accelerator.

  15. Symposium on accelerator mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    None

    1981-01-01

    The area of accelerator mass spectrometry has expanded considerably over the past few years and established itself as an independent and interdisciplinary research field. Three years have passed since the first meeting was held at Rochester. A Symposium on Accelerator Mass Spectrometry was held at Argonne on May 11-13, 1981. In attendance were 96 scientists of whom 26 were from outside the United States. The present proceedings document the program and excitement of the field. Papers are arranged according to the original program. A few papers not presented at the meeting have been added to complete the information on the status of accelerator mass spectrometry. Individual papers were prepared separately for the data base.

  16. Niobium LEP 2 accelerating cavities

    CERN Multimedia

    An accelerating cavity from LEP. This could be cut open to show the layer of niobium on the inside. Operating at 4.2 degrees above absolute zero, the niobium is superconducting and carries an accelerating field of 6 million volts per metre with negligible losses. Each cavity has a surface of 6 m2. The niobium layer is only 1.2 microns thick, ten times thinner than a hair. Such a large area had never been coated to such a high accuracy. A speck of dust could ruin the performance of the whole cavity so the work had to be done in an extremely clean environment. These challenging requirements pushed European industry to new achievements. 256 of these cavities were used in an upgrade of the LEP accelerator to double the energy of the particle beams.

  17. Symposium on accelerator mass spectrometry

    International Nuclear Information System (INIS)

    1981-01-01

    The area of accelerator mass spectrometry has expanded considerably over the past few years and established itself as an independent and interdisciplinary research field. Three years have passed since the first meeting was held at Rochester. A Symposium on Accelerator Mass Spectrometry was held at Argonne on May 11-13, 1981. In attendance were 96 scientists of whom 26 were from outside the United States. The present proceedings document the program and excitement of the field. Papers are arranged according to the original program. A few papers not presented at the meeting have been added to complete the information on the status of accelerator mass spectrometry. Individual papers were prepared separately for the data base

  18. Accelerator science in medical physics.

    Science.gov (United States)

    Peach, K; Wilson, P; Jones, B

    2011-12-01

    The use of cyclotrons and synchrotrons to accelerate charged particles in hospital settings for the purpose of cancer therapy is increasing. Consequently, there is a growing demand from medical physicists, radiographers, physicians and oncologists for articles that explain the basic physical concepts of these technologies. There are unique advantages and disadvantages to all methods of acceleration. Several promising alternative methods of accelerating particles also have to be considered since they will become increasingly available with time; however, there are still many technical problems with these that require solving. This article serves as an introduction to this complex area of physics, and will be of benefit to those engaged in cancer therapy, or who intend to acquire such technologies in the future.

  19. Advanced accelerator research and development

    International Nuclear Information System (INIS)

    Anon.

    1974-01-01

    Research and development on the Positron-Electron Project (PEP), the electron rings, the superconducting accelerator (ESCAR), and the superconductivity program are reported. Efforts relating to the proposed PEP include work on: (1) the injection system; (2) the rf system; (3) the main-ring bend magnets; (4) the magnet power supplies and controls; (5) alignment; (6) radiation and shielding; (7) the vacuum system; and (8) conventional facilities (utilities, etc.). Experimental and theoretical work continued on the development of suitably intense electron rings as vehicles for the collective acceleration of ions. The most difficult problem was found to be the longitudinal (negative mass) instability. Design work was begun for ESCAR (Experimental Superconducting Accelerating Ring), a small proton synchrotron and storage ring using superconducting magnets, which should aid in the design of future large superconducting facilities. Magnet development was largely directed toward the detailed design of the dipole units. A superconducting beam transport line was installed at the Bevatron. (PMA)

  20. Harmonic ratcheting for fast acceleration

    Directory of Open Access Journals (Sweden)

    N. Cook

    2014-04-01

    Full Text Available A major challenge in the design of rf cavities for the acceleration of medium-energy charged ions is the need to rapidly sweep the radio frequency over a large range. From low-power medical synchrotrons to high-power accelerator driven subcritical reactor systems, and from fixed focus alternating gradient accelerators to rapid cycling synchrotrons, there is a strong need for more efficient, and faster, acceleration of protons and light ions in the semirelativistic range of hundreds of MeV/u. A conventional way to achieve a large, rapid frequency sweep (perhaps over a range of a factor of 6 is to use custom-designed ferrite-loaded cavities. Ferrite rings enable the precise tuning of the resonant frequency of a cavity, through the control of the incremental permeability that is possible by introducing a pseudoconstant azimuthal magnetic field. However, rapid changes over large permeability ranges incur anomalous behavior such as the “Q-loss” and “f-dot” loss phenomena that limit performance while requiring high bias currents. Notwithstanding the incomplete understanding of these phenomena, they can be ameliorated by introducing a “harmonic ratcheting” acceleration scheme in which two or more rf cavities take turns accelerating the beam—one turns on when the other turns off, at different harmonics—so that the radio frequency can be constrained to remain in a smaller range. Harmonic ratcheting also has straightforward performance advantages, depending on the particular parameter set at hand. In some typical cases it is possible to halve the length of the cavities, or to double the effective gap voltage, or to double the repetition rate. This paper discusses and quantifies the advantages of harmonic ratcheting in general. Simulation results for the particular case of a rapid cycling medical synchrotron ratcheting from harmonic number 9 to 2 show that stability and performance criteria are met even when realistic engineering details

  1. Accelerator-induced transients in Accelerator Driven Subcritical Reactors

    Science.gov (United States)

    Ahmad, Ali; Lindley, Benjamin A.; Parks, Geoffrey T.

    2012-12-01

    Achieving higher particles energies and beam powers have long been the main focus of research in accelerator technology. Since Accelerator Driven Subcritical Reactors (ADSRs) have become the subject of increasing interest, accelerator reliability and modes of operation have become important matters that require further research and development in order to accommodate the engineering and economic needs of ADSRs. This paper focuses on neutronic and thermo-mechanical analyses of accelerator-induced transients in an ADSR. Such transients fall into three main categories: beam interruptions (trips), pulsed-beam operation, and beam overpower. The concept of a multiple-target ADSR is shown to increase system reliability and to mitigate the negative effects of beam interruptions, such as thermal cyclic fatigue in the fuel cladding and the huge financial cost of total power loss. This work also demonstrates the effectiveness of the temperature-to-reactivity feedback mechanisms in ADSRs. A comparison of shutdown mechanisms using control rods and beam cut-off highlights the intrinsic safety features of ADSRs. It is evident that the presence of control rods is crucial in an industrial-scale ADSR. This paper also proposes a method to monitor core reactivity online using the repetitive pattern of beam current fluctuations in a pulsed-beam operation mode. Results were produced using PTS-ADS, a computer code developed specifically to study the dynamic neutronic and thermal responses to beam transients in subcritical reactor systems.

  2. Acceleration parameters for fluid physics with accelerating bodies

    CSIR Research Space (South Africa)

    Gledhill, Irvy MA

    2016-06-01

    Full Text Available accelerating bodies, and reference must be made, above all, to the Mach number for transonic effects. Other parameters from the literature on impulsive start-up in wind tunnels are also shown to be useful in delimiting regimes of flow, such as the Freymuth...

  3. Pelletron ion accelerator facilities at Inter University Accelerator Centre

    International Nuclear Information System (INIS)

    Chopra, S.

    2011-01-01

    Inter University Accelerator Centre has two tandem ion accelerators, 15UD Pelletron and 5SDH-2 Pelletron, for use in different areas of research. Recently Accelerator Mass Spectrometry facility has also been added to to the existing experimental facilities of 15UD Pelletron. In these years many modifications and up gradations have been performed to 15UD Pelletron facility. A new MCSNICS ion source has been procured to produce high currents for AMS program. Two foils stripper assemblies ,one each before and after analyzing magnet, have also been added for producing higher charge state beams for LINAC and for experiments requiring higher charge states of accelerated beams. A new 1.7 MV Pelletron facility has also been recently installed at IUAC and it is equipped with RBS and Channelling experimental facility. There are two beam lines installed in the system and five more beam lines can be added to the system. A clean chemistry laboratory with all the modern facilities has also been developed at IUAC for the chemical processing of samples prior to the AMS measurements. The operational description of the Pelletron facilities, chemical processing of samples, methods of measurements and results of AMS measurements are being presented. (author)

  4. Health physics practices at research accelerators

    International Nuclear Information System (INIS)

    Thomas, R.H.

    1976-02-01

    A review is given of the uses of particle accelerators in health physics, the text being a short course given at the Health Physics Society Ninth Midyear Topical Symposium in February, 1976. Topics discussed include: (1) the radiation environment of high energy accelerators; (2) dosimetry at research accelerators; (3) shielding; (4) induced activity; (5) environmental impact of high energy accelerators; (6) population dose equivalent calculation; and (7) the application of the ''as low as practicable concept'' at accelerators

  5. The Brookhaven National Laboratory Accelerator Test Facility

    International Nuclear Information System (INIS)

    Batchelor, K.

    1992-01-01

    The Brookhaven National Laboratory Accelerator Test Facility comprises a 50 MeV traveling wave electron linear accelerator utilizing a high gradient, photo-excited, raidofrequency electron gun as an injector and an experimental area for study of new acceleration methods or advanced radiation sources using free electron lasers. Early operation of the linear accelerator system including calculated and measured beam parameters are presented together with the experimental program for accelerator physics and free electron laser studies

  6. Present status of the KEK digital accelerator

    International Nuclear Information System (INIS)

    Takayama, K.; Adachi, T.; Arai, T.

    2010-01-01

    An induction synchrotron has been developed and it has been demonstrated in 2006. Since the induction acceleration system has no limit on a frequency band-width, arbitrary ion species can be accelerated at their possible charge state. Direct injection of an ion beam from an ion source to the synchrotron is possible. We call such a synchrotron as 'All-ion accelerator' or 'Digital Accelerator'. The present status of the first Digital Accelerator under construction at KEK is reported. (author)

  7. New ideas for accelerating particles

    International Nuclear Information System (INIS)

    Lawson, J.D.

    1983-01-01

    Many different schemes can be devised for accelerating particles. In recent years several concepts radically different from those in common use have been suggested. Many of these have failed to live up to the hopes of their inventors. Now that we seem near the end of the road for large conventional machines, there is a renewed interest in alternatives, especially those involving lasers. Afte After a brief historical introduction and a discussion on how to classify different types of accelerator, some of these alternative concepts will be reviewed. (author)

  8. Chaotic dynamics in accelerator physics

    International Nuclear Information System (INIS)

    Cary, J.R.

    1992-01-01

    Substantial progress was in several areas of accelerator dynamics. For developing understanding of longitudinal adiabatic dynamics, and for creating efficiency enhancements of recirculating free-electron lasers, was substantially completed. A computer code for analyzing the critical KAM tori that bound the dynamic aperture in circular machines was developed. Studies of modes that arise due to the interaction of coating beams with a narrow-spectrum impedance have begun. During this research educational and research ties with the accelerator community at large have been strengthened

  9. Electron Cloud Effects in Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Furman, M.A.

    2012-11-30

    Abstract We present a brief summary of various aspects of the electron-cloud effect (ECE) in accelerators. For further details, the reader is encouraged to refer to the proceedings of many prior workshops, either dedicated to EC or with significant EC contents, including the entire ?ECLOUD? series [1?22]. In addition, the proceedings of the various flavors of Particle Accelerator Conferences [23] contain a large number of EC-related publications. The ICFA Beam Dynamics Newsletter series [24] contains one dedicated issue, and several occasional articles, on EC. An extensive reference database is the LHC website on EC [25].

  10. Electron Cloud Effects in Accelerators

    International Nuclear Information System (INIS)

    Furman, M A

    2013-01-01

    We present a brief summary of various aspects of the electron-cloud effect (ECE) in accelerators. For further details, the reader is encouraged to refer to the proceedings of many prior workshops, either dedicated to EC or with significant EC contents, including the entire 'ECLOUD' series. In addition, the proceedings of the various flavors of Particle Accelerator Conferences contain a large number of EC-related publications. The ICFA Beam Dynamics Newsletter series contains one dedicated issue, and several occasional articles, on EC. An extensive reference database is the LHC website on EC. (author)

  11. Metamaterials for optical Bragg accelerators

    Science.gov (United States)

    Hanuka, Adi; Goldemberg, Elron; Zilka, Almog; Schächter, Levi

    2018-03-01

    We present a systematic study of the advantages of using optical artificial materials in designing periodic structures for laser-driven accelerators. As a case study, we investigate the electromagnetic properties of a Bragg waveguide, with its alternating layers being composed of artificial materials. The layers can be optimized to maximize the structure's properties. We show that when the structure's eigenmode interacts with free electrons, the maximum efficiency is nearly four times higher than in configurations that rely on natural materials. As a result, accelerators and radiation sources may be miniaturized significantly.

  12. Thermodynamics of Accelerating Black Holes.

    Science.gov (United States)

    Appels, Michael; Gregory, Ruth; Kubizňák, David

    2016-09-23

    We address a long-standing problem of describing the thermodynamics of an accelerating black hole. We derive a standard first law of black hole thermodynamics, with the usual identification of entropy proportional to the area of the event horizon-even though the event horizon contains a conical singularity. This result not only extends the applicability of black hole thermodynamics to realms previously not anticipated, it also opens a possibility for studying novel properties of an important class of exact radiative solutions of Einstein equations describing accelerated objects. We discuss the thermodynamic volume, stability, and phase structure of these black holes.

  13. Centralized digital control of accelerators

    International Nuclear Information System (INIS)

    Melen, R.E.

    1983-09-01

    In contrasting the title of this paper with a second paper to be presented at this conference entitled Distributed Digital Control of Accelerators, a potential reader might be led to believe that this paper will focus on systems whose computing intelligence is centered in one or more computers in a centralized location. Instead, this paper will describe the architectural evolution of SLAC's computer based accelerator control systems with respect to the distribution of their intelligence. However, the use of the word centralized in the title is appropriate because these systems are based on the use of centralized large and computationally powerful processors that are typically supported by networks of smaller distributed processors

  14. Ion sources for medical accelerators

    Science.gov (United States)

    Barletta, W. A.; Chu, W. T.; Leung, K. N.

    1998-02-01

    Advanced injector systems for proton synchrotrons and accelerator-based boron neutron capture therapy systems are being developed at the Lawrence Berkeley National Laboratory. Multicusp ion sources, particularly those driven by radio frequency, have been tested for these applications. The use of a radio frequency induction discharge provides clean, reliable, and long-life source operation. It has been demonstrated that the multicusp ion source can provide good-quality positive hydrogen ion beams with a monatomic ion fraction higher than 90%. The extractable ion current densities from this type of source can meet the injector requirements for both proton synchrotron and accelerator-based boron neutron capture therapy projects.

  15. Calorimetry at industrial electron accelerators

    DEFF Research Database (Denmark)

    Miller, Arne; Kovacs, A.

    1985-01-01

    Calorimetry is a convenient way to measure doses at industrial electron accelerators, where high absorbed doses (1-100 kGy) are delivered at dose rates of 102-105 Gy s-1 or even higher. Water calorimeters have been used for this purpose for several years, but recently other materials such as grap......Calorimetry is a convenient way to measure doses at industrial electron accelerators, where high absorbed doses (1-100 kGy) are delivered at dose rates of 102-105 Gy s-1 or even higher. Water calorimeters have been used for this purpose for several years, but recently other materials...

  16. Muon Acceleration R and D

    International Nuclear Information System (INIS)

    Torun, Yagmur

    2009-01-01

    An intense muon source can be built in stages to support a uniquely broad program in high energy physics. Starting with a low-energy cooled muon beam, extraordinarily precise lepton flavor violation experiments are possible. Upgrading the facility with acceleration and a muon storage ring, one can build a Neutrino Factory that would allow a neutrino mixing physics program with unprecedented precision. Adding further acceleration and a collider ring, an energy-frontier muon collider can explore electroweak symmetry breaking and open a window to new physics.

  17. OpenMP for Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Beyer, J C; Stotzer, E J; Hart, A; de Supinski, B R

    2011-03-15

    OpenMP [13] is the dominant programming model for shared-memory parallelism in C, C++ and Fortran due to its easy-to-use directive-based style, portability and broad support by compiler vendors. Similar characteristics are needed for a programming model for devices such as GPUs and DSPs that are gaining popularity to accelerate compute-intensive application regions. This paper presents extensions to OpenMP that provide that programming model. Our results demonstrate that a high-level programming model can provide accelerated performance comparable to hand-coded implementations in CUDA.

  18. Double pulse laser wakefield accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Changbum [Department of Physics, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of)], E-mail: chbkim@postech.ac.kr; Kim, Jin-Cheol B. [Department of Physics, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of); Kim, Kukhee [National Fusion Reserch Center, Daejeon 305-333 (Korea, Republic of); Ko, In Soo [Department of Physics, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of); Suk, Hyyong [Center for Advanced Accelerators, Korea Electrotechnology Research Institute, Changwon 641-120 (Korea, Republic of)

    2007-10-22

    Two-dimensional simulation studies are performed for modified laser wakefield acceleration. After one laser pulse, another identical laser pulse is sent to the plasma to amplify the wake wave resonantly. The simulation results show that the number of injected electrons is bigger than that of the single pulse case and the beam energy is higher as well. In addition, increase of the transverse amplitude is noticed in the wake wave after the second laser pulse. This shows that the transverse motion of the wake wave enhances the wave breaking for strong injection and acceleration of electron beams.

  19. Principle of accelerator mass spectrometry

    International Nuclear Information System (INIS)

    Matsuzaki, Hiroyuki

    2007-01-01

    The principle of accelerator mass spectrometry (AMS) is described mainly on technical aspects: hardware construction of AMS, measurement of isotope ratio, sensitivity of measurement (measuring limit), measuring accuracy, and application of data. The content may be summarized as follows: rare isotope (often long-lived radioactive isotope) can be detected by various use of the ion energy obtained by the acceleration of ions, a measurable isotope ratio is one of rare isotope to abundant isotopes, and a measured value of isotope ratio is uncertainty to true one. Such a fact must be kept in mind on the use of AMS data to application research. (M.H.)

  20. Modern control techniques for accelerators

    International Nuclear Information System (INIS)

    Goodwin, R.W.; Shea, M.F.

    1984-01-01

    Beginning in the mid to late sixties, most new accelerators were designed to include computer based control systems. Although each installation differed in detail, the technology of the sixties and early to mid seventies dictated an architecture that was essentially the same for the control systems of that era. A mini-computer was connected to the hardware and to a console. Two developments have changed the architecture of modern systems: the microprocessor and local area networks. This paper discusses these two developments and demonstrates their impact on control system design and implementation by way of describing a possible architecture for any size of accelerator. Both hardware and software aspects are included