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Sample records for rapid break induction

  1. Induction and repair of double- and single-strand DNA breaks in bacteriophage lambda superinfecting Escherichia coli

    International Nuclear Information System (INIS)

    Boye, E.; Krisch, R.E.

    1980-01-01

    Induction and repair of double-and single-strand DNA breaks have been measured after decays of 125 I and 3 H incorporated into the DNA and after external irradiation with 4 MeV electrons. For the decay experiments, cells of wild type Escherichia coli K-12 were superinfected with bacteriophage lambda DNA labelled with 5'-( 125 I)iodo-2'-deoxyuridine or with (methyl- 3 H)thymidine and frozen in liquid nitrogen. Aliquots were thawed at intervals and lysed at neutral pH, and the phage DNA was assayed for double- and single-strand breakage by neutral sucrose gradient centrifugation. The gradients used allowed measurements of both kinds of breaks in the same gradient. Decays of 125 I induced 0.39 single-strand breaks per double-strand break. No repair of either break type could be detected. Each 3 H disintegration caused 0.20 single-strand breaks and very few double-strand breaks. The single-strand breaks were rapidly rejoined after the cells were thawed. For irradiation with 4 MeV electrons, cells of wild type E. coli K-12 were superinfected with phage lambda and suspended in growth medium. Irradiation induced 42 single-strand breaks per double-strand break. The rates of break induction were 6.75 x 10 -14 (double-strand breaks) and 2.82 x 10 -12 (single-strand breaks) per rad and per dalton. The single-strand breaks were rapidly repaired upon incubation whereas the double-strand breaks seemed to remain unrepaired. It is concluded that double-strand breaks in superinfecting bacteriophage lambda DNA are repaired to a very small extent, if at all. (Author)

  2. Rapid induction of false memory for pictures.

    Science.gov (United States)

    Weinstein, Yana; Shanks, David R

    2010-07-01

    Recognition of pictures is typically extremely accurate, and it is thus unclear whether the reconstructive nature of memory can yield substantial false recognition of highly individuated stimuli. A procedure for the rapid induction of false memories for distinctive colour photographs is proposed. Participants studied a set of object pictures followed by a list of words naming those objects, but embedded in the list were names of unseen objects. When subsequently shown full colour pictures of these unseen objects, participants consistently claimed that they had seen them, while discriminating with high accuracy between studied pictures and new pictures whose names did not appear in the misleading word list. These false memories can be reported with high confidence as well as the feeling of recollection. This new procedure allows the investigation of factors that influence false memory reports with ecologically valid stimuli and of the similarities and differences between true and false memories.

  3. Evaluation of Breaking Performance in Vibration-Assisted Electrostatic Surface Induction Actuator

    DEFF Research Database (Denmark)

    Nemoto, Takeru; Zsurzsan, Tiberiu-Gabriel; Yamamoto, Akio

    2015-01-01

    This paper evaluates breaking performance of an electrostatic surface induction actuator. The actuator is equipped with piezoelectric vibrator such that the friction between the slider and the stator electrodes can be dramatically reduced by squeeze-film effect. In such an actuator, the friction...... conditions. The result clearly shows the effect of friction change in breaking performance of the actuator....

  4. Rapid induction of autoantibodies during ARDS and septic shock

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    Meduri G Umberto

    2010-10-01

    Full Text Available Abstract Background Little is known about the induction of humoral responses directed against human autoantigens during acute inflammation. We utilized a highly sensitive antibody profiling technology to study autoantibodies in patients with acute respiratory distress syndrome (ARDS and severe sepsis, conditions characterized by intensive immune activation leading to multiple organ dysfunction. Methods Using Luciferase Immunoprecipitation Systems (LIPS, a cohort of control, ARDS and sepsis patients were tested for antibodies to a panel of autoantigens. Autoantibody titers greater than the mean plus 3 SD of the 24 control samples were used to identify seropositive samples. Available longitudinal samples from different seropositive ARDS and sepsis patient samples, starting from within the first two days after admission to the intensive care, were then analyzed for changes in autoantibody over time. Results From screening patient plasma, 57% of ARDS and 46% of septic patients without ARDS demonstrated at least one statistically significant elevated autoantibody compared to the controls. Frequent high titer antibodies were detected against a spectrum of autoantigens including potassium channel regulator, gastric ATPase, glutamic decarboxylase-65 and several cytokines. Analysis of serial samples revealed that several seropositive patients had low autoantibodies at early time points that often rose precipitously and peaked between days 7-14. Further, the use of therapeutic doses of corticosteroids did not diminish the rise in autoantibody titers. In some cases, the patient autoantibody titers remained elevated through the last serum sample collected. Conclusion The rapid induction of autoantibodies in ARDS and severe sepsis suggests that ongoing systemic inflammation and associated tissue destruction mediate the break in tolerance against these self proteins.

  5. Sizing of the Series Dynamic Breaking Resistor in a Doubly Fed Induction Generator Wind Turbine

    DEFF Research Database (Denmark)

    Soliman, Hammam; Wang, Huai; Zhou, Dao

    2014-01-01

    This paper investigates the effect of Series Dynamic Breaking Resistor (SDBR) sizing on a Doubly Fed Induction Generator (DFIG) based wind power conversion system. The boundary of the SDBR value is firstly derived by taking into account the controllability of the rotor side converter and the maxi......This paper investigates the effect of Series Dynamic Breaking Resistor (SDBR) sizing on a Doubly Fed Induction Generator (DFIG) based wind power conversion system. The boundary of the SDBR value is firstly derived by taking into account the controllability of the rotor side converter...... and the maximum allowable voltage of the stator. Then the impact of the SDBR value on the rotor current, stator voltage, DC-link voltage, reactive power capability and introduced power loss during voltage sag operation is evaluated by simulation. The presented study enables a trade-off sizing of the SDBR among...

  6. Failed rapid sequence induction in an achondroplastic dwarf

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    Jasleen Kaur

    2011-01-01

    Full Text Available Achondroplasia, a common cause of short limbed type of dwarfism is due to quantitative decrease in rate of endochondral ossification. This abnormal bone growth leads to disproportionate body and head structure, thus placing them under high risk for anaesthetic management. There is paucity in literatures, regarding appropriate drug dosage selection in these patients. Use of drugs as per standard dosage recommendations based on body weight or body surface area, may not be adequate in these patients owing to discrepancies in overall body weight and lean body weight, especially during rapid sequence induction. Here, we report a case of failed rapid sequence induction due to abnormal response to administered drugs in an adult achondroplastic dwarf. Standard doses of thiopentone and rocuronium had to be repeated thrice to achieve adequate conditions for intubation.

  7. Rapid sequence induction has no use in pediatric anesthesia.

    Science.gov (United States)

    Engelhardt, Thomas

    2015-01-01

    (Classic) rapid sequence induction and intubation (RSII) has been considered fundamental to the provision of safe anesthesia. This technique consists of a combination of drugs and techniques and is intended to prevent pulmonary aspiration of gastric content with catastrophic outcomes to the patient. This review investigates aspects of this technique and highlights dangers and frauds if this technique is transferred directly into pediatric anesthesia practice. The author recommends a controlled anesthesia induction by trained pediatric anesthesiologist with suitable equipment for the children considered at risk of pulmonary aspiration. RSSI is a dangerous technique if adopted without modification into pediatric anesthesia and has in its 'classic' form no use. © 2014 John Wiley & Sons Ltd.

  8. Ultra-modified rapid sequence induction with transnasal humidified rapid insufflation ventilatory exchange: Challenging convention

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    Ketan Sakharam Kulkarni

    2018-01-01

    Full Text Available During positive pressure ventilation, gastric inflation and subsequent pulmonary aspiration can occur. Rapid sequence induction (RSI technique is an age-old formula to prevent this. We adopted a novel approach of RSI for patients with high risk of aspiration and evaluated it further in patients undergoing laparoscopic surgeries. We believe that, in patients with risk of gastric insufflation and pulmonary aspiration, transnasal humidified rapid-insufflation ventilatory exchange can be useful in facilitating pre- and apnoeic oxygenation till tracheal isolation is achieved.

  9. Improve germination of caper (Capparis Spinosa l. seeds by different induction treatments of seed dormancy breaking

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    M. R. Labbafi

    2018-03-01

    Full Text Available Seed dormancy is a common phase of the plant life cycle; different treatments can be used for breaking dormancy. The aim of this study was to find the best treatment for breaking dormancy and improve germination of caper (Capparis spinosa L.. This study based on the completely randomized design (CRD with 3 replications was done at research Laboratory of Medicinal Plants Institute, ACECR, Karaj, Iran. After different induction treatments containing different levels of potassium nitrate (KNO3, GA3, soaking and soaking with runner water, sulfuric acid, thidiazuron, and benzyl amino-purine, seeds were placed in Petri-dishes and incubated in two temperature regimes, first at fixed 20 ͦC, and second, alternate between 20 and 30 ͦC. The result showed that the germination percentage and germination rate of caper increased up to 75% and 1.35 respectively when the seeds treated with sulfuric acid for 15 min, and 2000 ppm GA3 under alternate 20-30 ͦC temperatures. Caper seed dormancy is mainly due to the inhibitors and hard seed coat that it prevents seed germination.

  10. Rocuronium versus succinylcholine for rapid sequence induction intubation.

    Science.gov (United States)

    Tran, Diem T T; Newton, Ethan K; Mount, Victoria A H; Lee, Jacques S; Wells, George A; Perry, Jeffrey J

    2015-10-29

    Patients often require a rapid sequence induction (RSI) endotracheal intubation technique during emergencies or electively to protect against aspiration, increased intracranial pressure, or to facilitate intubation. Traditionally succinylcholine has been the most commonly used muscle relaxant for this purpose because of its fast onset and short duration; unfortunately, it can have serious side effects. Rocuronium has been suggested as an alternative to succinylcholine for intubation. This is an update of our Cochrane review published first in 2003 and then updated in 2008 and now in 2015. To determine whether rocuronium creates intubating conditions comparable to those of succinylcholine during RSI intubation. In our initial review we searched all databases until March 2000, followed by an update to June 2007. This latest update included searching the Cochrane Central Register of Controlled Trials (CENTRAL; 2015, Issue 2), MEDLINE (1966 to February Week 2 2015), and EMBASE (1988 to February 14 2015 ) for randomized controlled trials (RCTs) or controlled clinical trials (CCTs) relating to the use of rocuronium and succinylcholine. We included foreign language journals and handsearched the references of identified studies for additional citations. We included any RCT or CCT that reported intubating conditions in comparing the use of rocuronium and succinylcholine for RSI or modified RSI in any age group or clinical setting. The dose of rocuronium was at least 0.6 mg/kg and succinylcholine was at least 1 mg/kg. Two authors (EN and DT) independently extracted data and assessed methodological quality for the 'Risk of bias' tables. We combined the outcomes in Review Manager 5 using a risk ratio (RR) with a random-effects model. The previous update (2008) had identified 53 potential studies and included 37 combined for meta-analysis. In this latest update we identified a further 13 studies and included 11, summarizing the results of 50 trials including 4151 participants

  11. Induction of DNA strand breaks by RSU-1069, a nitroimidazole-aziridine radiosensitizer

    International Nuclear Information System (INIS)

    Silver, A.R.J.; O'Neill, P.; Jenkins, T.C.

    1985-01-01

    [2- 14 C]-RSU-1069 [1-(2-nitro-1-imidazolyl)-3-(1-aziridino)-2-propanol], either as a parent or following radiation reduction, binds to calf thymus DNA in vitro. Radiation-reduced RSU-1069 binds to a greater extent and more rapidly than the parent compound. RSU-1137, a non-aziridino analogue of RSU-1069, binds following radiation reduction. Radiation-reduced misonidazole exhibits binding ratios a thousand-fold less than those of reduced RSU-1069. Both parent and reduced RSU-1069 cause single strand breaks (ssbs) in pSV2 gpt plasmid DNA with the reduced compound causing a greater number of breaks. Parent and reduced RSU-1137 and misonidazole do not cause ssbs. It is inferred that the aziridine moiety present in both parent and reduced RSU-1069 is required for ssb production. RSU-1069 reacts with inorganic phosphate probably via nucleophilic ring-opening of the aziridine fragment. Incubation of plasmid DNA with reduced RSU-1069 in the presence of either phosphate or deoxyribose-5-phosphate at concentrations greater than 0.35 mol dm -3 prevents strand breakage, whereas 1.2 mol dm -3 deoxyribose does not protect against strand breakage formation. It is proposed that the observed binding to DNA occurs via the aziridine and the reduced nitro group of RSU-1069 and that these two have different target sites. Binding to DNA via the reduced nitro group may serve to increase aziridine attack due to localization at or near its target. (author)

  12. Mangrove forest against dyke-break-induced tsunami on rapidly subsiding coasts

    Science.gov (United States)

    Takagi, Hiroshi; Mikami, Takahito; Fujii, Daisuke; Esteban, Miguel; Kurobe, Shota

    2016-07-01

    Thin coastal dykes typically found in developing countries may suddenly collapse due to rapid land subsidence, material ageing, sea-level rise, high wave attack, earthquakes, landslides, or a collision with vessels. Such a failure could trigger dam-break tsunami-type flooding, or "dyke-break-induced tsunami", a possibility which has so far been overlooked in the field of coastal disaster science and management. To analyse the potential consequences of one such flooding event caused by a dyke failure, a hydrodynamic model was constructed based on the authors' field surveys of a vulnerable coastal location in Jakarta, Indonesia. In a 2 m land subsidence scenario - which is expected to take place in the study area after only about 10-20 years - the model results show that the floodwaters rapidly rise to a height of nearly 3 m, resembling the flooding pattern of earthquake-induced tsunamis. The depth-velocity product criterion suggests that many of the narrow pedestrian paths behind the dyke could experience strong flows, which are far greater than the safe limits that would allow pedestrian evacuation. A couple of alternative scenarios were also considered to investigate how such flood impacts could be mitigated by creating a mangrove belt in front of the dyke as an additional safety measure. The dyke-break-induced tsunamis, which in many areas are far more likely than regular earthquake tsunamis, cannot be overlooked and thus should be considered in disaster management and urban planning along the coasts of many developing countries.

  13. Effect of cellular glutathione content on the induction of DNA double strand breaks by 25 MeV electrons

    Energy Technology Data Exchange (ETDEWEB)

    Frankenberg, D.; Kistler, M.; Eckhardt-Schupp, F.

    1987-08-01

    The effect of endogenous glutathione (GSH) on the induction of DNA double strand breaks (dsb) by 25 MeV electrons was investigated using stationary haploid yeast cells defective in ..gamma..-glutamyl-cysteine-synthetase (gsh 1) containing less than 5 per cent of the normal GSH content. In gsh 1 cells the induction of dsb is increased by a factor of 1.5 under oxic and 1.8 under anoxic irradiation conditions whereas the oxygen enhancement ratio was only slightly decreased (1.9) compared to wild-type cells (2.4).

  14. Effect of cellular glutathione content on the induction of DNA double strand breaks by 25 MeV electrons

    International Nuclear Information System (INIS)

    Frankenberg, D.; Kistler, M.; Eckhardt-Schupp, F.

    1987-01-01

    The effect of endogenous glutathione (GSH) on the induction of DNA double strand breaks (dsb) by 25 MeV electrons was investigated using stationary haploid yeast cells defective in γ-glutamyl-cysteine-synthetase (gsh 1) containing less than 5 per cent of the normal GSH content. In gsh 1 cells the induction of dsb is increased by a factor of 1.5 under oxic and 1.8 under anoxic irradiation conditions whereas the oxygen enhancement ratio was only slightly decreased (1.9) compared to wild-type cells (2.4). (author)

  15. Induction and repair of DNA double-strand breaks in rat cerebellar cortex exposed to 60Co γ-rays

    Science.gov (United States)

    Bulanova, T. S.; Zadneprianetc, M. G.; Ježková, L.; Kruglyakova, E. A.; Smirnova, E. V.; Boreyko, A. V.

    2018-01-01

    The induction and repair of DNA double-strand breaks are studied using the immunohistochemical staining procedure of paraffin-embedded rat cerebellum tissues after exposure to γ-rays of 60Co. The dose dependence of radiation-induced colocalized γH2AX/53BP1 foci is studied and its linear character is established. It is shown that these foci are efficiently eliminated 24 h after irradiation.

  16. Rapid sequence induction and intubation with rocuronium-sugammadex compared with succinylcholine

    DEFF Research Database (Denmark)

    Sørensen, M K; Bretlau, C; Gätke, M R

    2012-01-01

    An unanticipated difficult airway may arise during rapid sequence induction and intubation (RSII). The aim of the trial was to assess how rapidly spontaneous ventilation could be re-established after RSII. We hypothesized that the time period from tracheal intubation to spontaneous ventilation wo...... would be shorter with rocuronium-sugammadex than with succinylcholine....

  17. Induction of DNA double-strand breaks in hepatoma cell SMMC-7721 by accelerated carbon ion 12C6+

    International Nuclear Information System (INIS)

    Lei Suwen; Su Xu; Wang Jufang; Zhao Jing; Li Wenjian

    2004-01-01

    DNA lesions, especially DNA double-strand breaks (dsbs), are looked upon as the dominant molecular effect of radiation action. Dsbs mark the beginning of a cascade of cellular processes that either results in complete repair of the DNA damage or lead to deleterious stages such as mutation, transformation or even cell death. Changing the radiation quality can influence the radiosensitivity of cells in culture. Accelerated particles provide an excellent means of varying the ionization density of the test radiation. With ion beams, the molecular mechanisms underlying the biological consequences of high linear energy transfer (LET) irradiation can be studied and describing radiation action with biophysical models can be tested. In this paper, radiation-induced DNA double-strand breaks (dsbs) were measured in hepatoma SMMC-7721 cells by means of an experimental approach involving pulsed-field gel electrophoresis and densitometric scanning of ethidium bromide stained gels. With this set-up, the induction of dsbs was investigated in SMMC-7721 cells after irradiation with accelerated carbon ions with specific LET 70 keV/μm. The fraction of DNA retained was taken as quantitative measure to calculate absolute yields of induced DNA dsbs. Experimental data shows that the induction of DNA dsbs increasing with the dose of irradiation. Data are compared with published results on dsbs induction in mammalian cells by radiations of comparable LET

  18. P53-mediated rapid induction of apoptosis conveys resistance to viral infection in Drosophila melanogaster.

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    Bo Liu

    2013-02-01

    Full Text Available Arthropod-borne pathogens account for millions of deaths each year. Understanding the genetic mechanisms controlling vector susceptibility to pathogens has profound implications for developing novel strategies for controlling insect-transmitted infectious diseases. The fact that many viruses carry genes that have anti-apoptotic activity has long led to the hypothesis that induction of apoptosis could be a fundamental innate immune response. However, the cellular mechanisms mediating the induction of apoptosis following viral infection remained enigmatic, which has prevented experimental verification of the functional significance of apoptosis in limiting viral infection in insects. In addition, studies with cultured insect cells have shown that there is sometimes a lack of apoptosis, or the pro-apoptotic response happens relatively late, thus casting doubt on the functional significance of apoptosis as an innate immunity. Using in vivo mosquito models and the native route of infection, we found that there is a rapid induction of reaper-like pro-apoptotic genes within a few hours following exposure to DNA or RNA viruses. Recapitulating a similar response in Drosophila, we found that this rapid induction of apoptosis requires the function of P53 and is mediated by a stress-responsive regulatory region upstream of reaper. More importantly, we showed that the rapid induction of apoptosis is responsible for preventing the expression of viral genes and blocking the infection. Genetic changes influencing this rapid induction of reaper-like pro-apoptotic genes led to significant differences in susceptibility to viral infection.

  19. INDUCTION OF DNA STRAND BREAKS BY TRIHALOMETHANES IN PRIMARY HUMAN LUNG EPITHELIAL CELLS

    Science.gov (United States)

    Abstract Trihalomethanes (TEMs) are disinfection by-products and suspected human carcinogens present in chlorinated drinking water. Previous studies have shown that many THMs induce sister chromatid exchanges and DNA strand breaks in human peripheral blood lymphocyte...

  20. Enzymatic induction of DNA double-strand breaks in γ-irradiated Escherichia coli K-12

    International Nuclear Information System (INIS)

    Bonura, T.; Smith, K.C.; Kaplan, H.S.

    1975-01-01

    The polA1 mutation increases the sensitivity of E. coli K-12 to killing by γ-irradiation in air by a factor of 2.9 and increases the yield of DNA double-strand breaks by a factor of 2.5. These additional DNA double-strand breaks appear to be due to the action of nucleases in the polA1 strain rather than to the rejoining of radiation-induced double-strand breaks in the pol + strain. This conclusion is based upon the observation that γ-irradiation at 3 0 did not affect the yield of DNA double-strand breaks in the pol + strain, but decreased the yield in the polA1 strain by a factor of 2.2. Irradiation of the polA1 strain at 3 0 followed by incubation at 3 0 for 20 min before plating resulted in approximately a 1.5-fold increase in the D 0 . The yield of DNA double-strand breaks was reduced by a factor of 1.5. The pol + strain, however, did not show the protective effect of the low temperature incubation upon either survival or DNA double-strand breakage. We suggest that the increased yield of DNA double-strand breaks in the polA 1 strain may be the result of the unsuccessful excision repair of ionizing radiation-induced dna base damage

  1. Induction of DNA strand breaks in 14C-labelled cells

    International Nuclear Information System (INIS)

    Sundell-Bergman, S.; Johanson, K.J.

    1979-01-01

    Chinese hamster cells grown in vitro were labelled with 14 C-thymidine for 18 hours and after 3 hours in non-radioactive medium they were stored at 0 0 C for various periods ( 1 to 12 hours). During this treatment a number of DNA strand breaks were induced by 14 C decay which were not repaired at 0 0 C. The number of DNA strand breaks was determined using the DNA unwinding technique. At 0.5-1 dpm per cell a detectable number of DNA strand breaks were found. Treatment for six hours (1 dpm per cell) reduced the percentage of double-stranded DNA from 80 to 70%, corresponding to about 750 DNA strand breaks per cell. The rejoining of DNA strand breaks was studied after treatment for 12 hours at 0 0 C followed by incubation of the cells for various periods at 37 0 C. Most of the DNA strand breaks induced by 14 C decay at 0 0 C were repaired after incubation at 37 0 C for 15 minutes. Assuming an absorbed dose of 1.8 mGy per 14 C decay to the cell nucleus an RBE value close to 1 was found for internal irradiation from 14 C decay as compared with 60 Co-gamma irradiation. (author)

  2. Rapid COJEC Induction Therapy for High-risk Neuroblastoma Patients - Cochrane Review.

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    Peinemann, F; van Dalen, E C; Berthold, F

    2016-04-01

    Neuroblastoma is a rare malignant disease and patients with high-risk neuroblastoma have a poor prognosis. Rapid COJEC induction chemotherapy means (almost) the same total doses given within a shorter time period. In theory, rapid COJEC could reduce the risk of drug resistance and it has been considered as a potential candidate for improving the outcome. The objective was to evaluate effects of rapid COJEC compared to standard induction chemotherapy in patients with high-risk neuroblastoma. We searched the databases CENTRAL, MEDLINE, and EMBASE from inception to 11 November 2014 and included randomized controlled trials. We identified one relevant randomized controlled trial with 130 participants receiving rapid COJEC and 132 participants receiving standard OPEC/COJEC induction chemotherapy. There was no statistically significant difference between the treatment groups in complete response (risk ratio 0.99, 95% confidence interval 0.71 to 1.38, P=0.94) and treatment-related mortality (risk ratio 1.21, 95% confidence interval 0.33 to 4.39, P=0.77). A statistically significant difference in favor of the standard treatment arm was identified for the following early toxicities: febrile neutropenia, septicemia, and renal toxicity. The differences in complete response and treatment-related mortality between treatment alternatives were not statistically significantly different. Based on the currently available evidence, we are uncertain about the effects of rapid COJEC induction chemotherapy in patients with high-risk neuroblastoma. © Georg Thieme Verlag KG Stuttgart · New York.

  3. Analysis of DNA strand break induction and repair in plants from the vicinity of Chernobyl

    International Nuclear Information System (INIS)

    Syomov, A.B.; Ptitsyna, S.N.; Sergeeva, S.A.

    1992-01-01

    For 3 years following the Chernobyl accident DNA repair efficiency was studied in irradiated and control populations of various plan species. Compared with the control populations, some irradiated populations exhibited increases in the yield of DNA single-strand breaks per unit dose of challenge radiation. The effect was registered in low-dose-rate alpha-irradiated populations, but was absent in plant populations growing in conditions of low-dose-rate beta-irradiation. The efficiency of single-strand DNA repair was identical in control and irradiated populations and approximated 100%. (author). 12 refs.; 1 fig.; 2 tabs

  4. Radioadaptive response to the medium-mediated bystander induction of DNA strand breaks in HeLa cells

    International Nuclear Information System (INIS)

    Ikushima, T.; Okuyama, M.

    2003-01-01

    Full text: Numerous investigators have reported two cellular responses of importance at low doses that have a potential impact on the risk estimation of ionizing radiation. The radioadaptive response confers resistance to a subsequent dose by a low priming dose, while the bystander effect exaggerates the effect of small doses. The present study was conducted to examine the interaction of the radioadaptive response with the bystander effect in HeLa cells. The culture was irradiated with 0.5 to 8 Gy of 140 kVp X-rays and one hour later, the medium was taken, passed through a filter and transferred to the parallel culture of non-irradiated HeLa cells as non-targeted cells. After incubation for 30 min, the induced DNA damage was analyzed by the single cell gel-electrophoresis assay under alkaline or neutral conditions. The treatments resulted in a dose-dependent increase in tail moment under either conditions, indicating the induction of DNA single- and double-strand breaks. The clonogenic survival of non-irradiated cells was also reduced after they were cultured in the medium that was taken from irradiated cultures. Any change was not observed when the medium alone was irradiated. These results give the disputed evidence that certain genotoxic factor(s) released from irradiated cells into the culture medium can induce DNA strand breaks leading to cell death. It is also suggested that physical contact between irradiated and non-irradiated cells may not be required for the bystander effect. In adapted cells that were pre-exposed to 5 cGy of X-rays and cultured for 4 h beforehand, the yield of DNA strand breaks induced by X-rayed medium was reduced by about 50 %. The results, in conjunction with our early finding (Ikushima et al., 1996) suggest that the radioadaptive response resulting from such a low dose may diminish the bystander effect through an enhanced DNA repair function

  5. Photosensitization by iodinated DNA minor groove binding ligands: Evaluation of DNA double-strand break induction and repair.

    Science.gov (United States)

    Briggs, Benjamin; Ververis, Katherine; Rodd, Annabelle L; Foong, Laura J L; Silva, Fernando M Da; Karagiannis, Tom C

    2011-05-03

    Iodinated DNA minor groove binding bibenzimidazoles represent a unique class of UVA photosensitizer and their extreme photopotency has been previously characterized. Earlier studies have included a comparison of three isomers, referred to as ortho-, meta- and para-iodoHoechst, which differ only in the location of the iodine substituent in the phenyl ring of the bibenzimidazole. DNA breakage and clonogenic survival studies in human erythroleukemic K562 cells have highlighted the higher photo-efficiency of the ortho-isomer (subsequently designated UV(A)Sens) compared to the meta- and para-isomers. In this study, the aim was to compare the induction and repair of DNA double-strand breaks induced by the three isomers in K562 cells. Further, we examined the effects of the prototypical broad-spectrum histone deacetylase inhibitor, Trichostatin A, on ortho-iodoHoechst/UVA-induced double-strand breaks in K562 cells. Using γH2AX as a molecular marker of the DNA lesions, our findings indicate a disparity in the induction and particularly, in the repair kinetics of double-strand breaks for the three isomers. The accumulation of γH2AX foci induced by the meta- and para-isomers returned to background levels within 24 and 48 h, respectively; the number of γH2AX foci induced by ortho-iodoHoechst remained elevated even after incubation for 96 h post-irradiation. These findings provide further evidence that the extreme photopotency of ortho-iodoHoechst is due to not only to the high quantum yield of dehalogenation, but also to the severity of the DNA lesions which are not readily repaired. Finally, our findings which indicate that Trichostatin A has a remarkable potentiating effect on ortho-iodoHoechst/UVA-induced DNA lesions are encouraging, particularly in the context of cutaneous T-cell lymphoma, for which a histone deacetylase inhibitor is already approved for therapy. This finding prompts further evaluation of the potential of combination therapies. Copyright © 2011

  6. Induction of DNA double-strand breaks by ionizing radiation of different quality and their relevance for cell inactivation

    International Nuclear Information System (INIS)

    Kampf, G.

    1988-01-01

    By investigation of the production of DNA strand breaks and of DNA release from the nuclear membrane complex in Chinese hamster cells using different radiation qualities from 1 to 360 keV/μm, partly also under hypoxic conditions, and by relating the results to the induction of chromosome aberrations and to cell inactivation it has become possible to find connections between the induction of molecular lesions and the expression of this damage on the cellular level. From the studies follows that DNA pieces are cut off from the nuclear membrane complex by DNA double-strand breaks (DSB). The share and size of the released pieces depends on radiation dose and quality as well as on the oxygen conditions. The lesions can partly be repaired. In connection with the DSB rates the results of the DNA release studies led to the conclusion that the DNA in the cells must be organized in superstructure units (MASSUs) with a DNA mass of about 2 x 10 9 g/mol, which are associated to the nuclear membrane in attachment points. The numerical relations show that for a 37% survival probability about 90 DSB per genome are required with sparsely ionizing radiation; this number declines to about 40 by use of more densely ionizing radiation up to 150 keV/μm, and increases again with further rise of the ionization density. Hence, for cell inactivation not simply a certain number of DSB per cell is required but rather seems their cooperation within a small structure section of the DNA to be relevant. These critical structures are with high probability the MASSUs. An irrepairable release of DNA from such a structure unit can bring about a chromosome break detectable in the metaphase and finally lead to cell inactivation. DSB turned out to be the essential lethal events in bacteria as well. The relatively small differences to the eukaryotic cells in the position of the maximum of radiation sensitivity on the LET scale and in the lesion sensitivity towards DSB let suggest that a common critical

  7. Measurement of intracellular DNA double-strand break induction and rejoining along the track of carbon and neon particle beams in water

    International Nuclear Information System (INIS)

    Heilmann, Johannes; Taucher-Scholz, Gisela; Haberer, Thomas; Scholz, Michael; Kraft, Gerhard

    1996-01-01

    Purpose: The study was aimed at the measurement of effect-depth distributions of intracellularly induced DNA damage in water as tissue equivalent after heavy ion irradiation with therapy particle beams. Methods and Materials: An assay involving embedding of Chinese hamster ovary (CHO-K1) cells in large agarose plugs and electrophoretic elution of radiation induced DNA fragments by constant field gel electrophoresis was developed. Double-strand break production was quantified by densitometric analysis of DNA-fluorescence after staining with ethidium-bromide and determination of the fraction of DNA eluted out of the agarose plugs. Intracellular double-strand break induction and the effect of a 3 h rejoining incubation were investigated following irradiation with 250 kV x-rays and 190 MeV/u carbon- and 295 MeV/u neon-ions. Results and Conclusion: While the DNA damage induced by x-irradiation decreased continuously with penetration depth, a steady increase in the yield of double-strand breaks was observed for particle radiation, reaching distinct maxima at the position of the physical Bragg peaks. Beyond this, the extent of radiation damage dropped drastically. From comparison of DNA damage and calculated dose profiles, relative biological efficiencies (RBEs) for both double-strand break induction and unrejoined strand breaks after 3 h were determined. While RBE for the induction of DNA double-strand breaks decreased continuously with penetration depth, RBE maxima greater than unity were found with carbon- and neon-ions for double-strand break rejoining near the maximum range of the particles. The method presented here allows for a fast and accurate determination of depth profiles of relevant radiobiological effects for mixed particle fields in tissue equivalent

  8. An empirical model for the induction of double strand breaks in DNA by the indirect' action of ionising radiation

    International Nuclear Information System (INIS)

    Watt, D.E.; Hill, S.J.A.

    1994-01-01

    For calculation of radiation effects at low doses near environmental levels it is necessary to model both ''direct'' and ''indirect'' effects along single charged particle tracks in the equilibrium spectrum generated by the radiation field. The modelling approach used here to determine the ''indirect'' contribution to the damage to the DNA in mammalian cells is first to study the transition of damage from the solid to liquid phases at different concentrations of enzyme targets (known to be inactivated by single target, single hit kinetics). The respective contributions from direct and indirect action can then be separated. Results obtained in this laboratory for the inactivation of dihydroorotate dehydrogenase have been supplemented by data taken from the literature. A simple model of the radiation action has been derived. It succeeds in correlating all the data within the range of concentrations, radical scavenger, and LET used. From the results, information is obtained on the role of the dose rate; on diffusion lengths, on the type of radical predominantly responsible (OH·) for the inactivation and on scavenging of radicals. Since water radicals are thought to be the main cause of indirect damage in mammalian cells it is a simple step to deduce from the enzyme results the probability of induction of single and double strand breaks in the DNA by making the assumption that basically the same radical kinetics are involved and then applying Poisson probabilities. (author)

  9. The influence of bromodeoxyuridine on the induction and repair of DNA double-strand breaks in glioblastoma cells

    International Nuclear Information System (INIS)

    Nusser, N.N.; Bartkowiak, D.; Roettinger, E.M.

    2002-01-01

    Aims: To examine the dose response of DNA damage and its modification by the radiosensitizer, 5-bromo-2'-deoxyuridine (BrdU). The sensitizing mechanism is analyzed with regard to its influence on the induction and repair of DNA double-strand breaks (DSBs). Material and Methods: Cells from three different human glioblastoma lines, A7, LH and U87MG, were X-irradiated with and without exposure to BrdU. DNA fragments were separated by field-inversion gel electrophoresis (FIGE) and quantified by fluorometry immediately and 24 h after irradiation. Results: In all cell lines, the dose response followed a linear-quadratic rather than a purely linear function. BrdU-treated cells exhibited a significantly higher amount of mobile DNA. In repair experiments with and without BrdU, the amount of mobile DNA fell close to control values within 24 h. Conclusions: The linear-quadratic model appropriately describes the X-ray induced fragmentation of DNA. BrdU sensitizing acts predominantly by increasing DNA fragility, and not by impairing damage repair. The amount of DSBs persistent after 24 h of repair is minimal, even after highly cytotoxic doses. However, it appears to depend on the extent of initial damage, causing sensitized cells to retain more DSBs than unsensitized cells. (orig.)

  10. Induction and disappearance of G2 chromatid breaks in lymphocytes after low doses of low LET γ - rays and high LET fast neutrons

    International Nuclear Information System (INIS)

    Vral, Anne; Thierens, Hubert; Baeyens, Ans; De Ridder, Leo

    2001-01-01

    In view of the potential importance of the G2 assay for detecting chromosomal radiosensitivity and possible predisposition to cancer the need to elucidate the mechanism underlying the formation of chromatid breaks, observed with the G2 assay after low dose irradiation, has been recognised. In this study we irradiated blood samples of 4 healthy donors with low LET γ-rays and high LET neutrons, which initially produce the same number of dsb but of a different quality. By means of the G2 assay, we determined the number of chromatid breaks induced by γ-rays and neutrons and compared the kinetics of chromatid break rejoining for radiations of different quality. In a first set of experiments a dose-response curve for the formation of chromatid breaks was carried out for γ-rays and neutrons with doses ranging between 0.1 and 0.5 Gy. In a second set of experiments the kinetics of chromatid break formation and disappearance was investigated after a dose of 0.5 Gy using post-irradiation times ranging between 0.5 h and 3.5 h. For the highest dose of 0.5 Gy the number of isochromatid breaks were also scored. No significant differences in the number of chromatid breaks were observed between low LET γ-rays and high LET neutrons for the 4 donors at any of the doses given. The dose response curves for the formation of chromatid breaks are linear for both radiation qualities and RBE values equal to one were obtained. Scoring of isochromatid breaks at the highest dose of 0.5 Gy revealed that high LET neutrons are however more effective at inducing isochromatid breaks (RBE of 6.2). The rejoining experiments further showed that the kinetics of disappearance of chromatid breaks following irradiation with low LET γ-rays or high-LET neutrons are not significantly different. T 1/2 0.92 h for γ-rays and t 1/2 = 0.84 h for neutrons were obtained. In conclusion, our results show that at low doses of radiation the induction as well as the disappearance of G2 chromatid breaks is LET

  11. The design evaluation of inductive power-transformer for personal rapid transit by measuring impedance

    International Nuclear Information System (INIS)

    Han, Kyung-Hee; Lee, Byung-Song; Baek, Soo-Hyun

    2008-01-01

    The contact-less inductive power transformer (IPT) uses the principle of electromagnetic induction. The concept of the IPT for vehicles such as the personal rapid transit (PRT) system is proposed and some suggestions for power collector design of IPT to improve power transfer performance are presented in this paper. The aim of this paper is to recommend the concept of IPT for vehicles such as the PRT system and also to present some propositions for the power collector design of the IPT, which is to improve the power transfer performance. Generally, there are diverse methods to evaluate transfer performance of the traditional transformers. Although the principle of IPT is similar to that of the general transformer, it is impossible to apply the methods directly because of large air gap. The system must be compensated by resonant circuit due to the large air gap. Consequently, it is difficult to apply numerical formulas to the magnetic design of IPT systems. This paper investigates the magnetic design of a PRT system using three-dimensional magnetic modeling and measurements of the pick-up coupling coefficient and its impedances. In addition, how the use of Litz wire and leakage inductance is related will be observed through experiment and simulation

  12. Rapid COJEC versus standard induction therapies for high-risk neuroblastoma.

    Science.gov (United States)

    Peinemann, Frank; Tushabe, Doreen A; van Dalen, Elvira C; Berthold, Frank

    2015-05-19

    Neuroblastoma is a rare malignant disease and mainly affects infants and very young children. The tumors mainly develop in the adrenal medullary tissue and an abdominal mass is the most common presentation. The high-risk group is characterized by metastasis and other characteristics that increase the risk for an adverse outcome. In the rapid COJEC induction schedule, higher single doses of selected drugs than standard induction schedules are administered over a substantially shorter treatment period, with shorter intervals between cycles. Shorter intervals and higher doses increase the dose intensity of chemotherapy and might improve survival. The aim of this study was to evaluate the efficacy and adverse events of the rapid COJEC induction schedule as compared to standard induction schedules in patients with high-risk neuroblastoma (as defined by the International Neuroblastoma Risk Group (INRG) classification system). Outcomes of interest were complete response, early toxicity and treatment-related mortality as primary endpoints and overall survival, progression- and event-free survival, late non-hematological toxicity, and health-related quality of life as secondary endpoints. We searched the electronic databases CENTRAL (2014, Issue 11), MEDLINE (PubMed), and EMBASE (Ovid) for articles from inception to 11 November 2014. Further searches included trial registries, conference proceedings, and reference lists of recent reviews and relevant articles. We did not apply limits on publication year or languages. Randomized controlled trials evaluating the rapid COJEC induction schedule for high-risk neuroblastoma patients compared to standard induction schedules. Two review authors performed study selection, abstracted data on study and patient characteristics, and assessed risk of bias independently. We resolved differences by discussion or by appeal to a third review author. We performed analyses according to the guidelines of the Cochrane Handbook for Systematic

  13. Induction and repair of DNA double strand breaks: The increasing spectrum of non-homologous end joining pathways

    International Nuclear Information System (INIS)

    Mladenov, Emil; Iliakis, George

    2011-01-01

    A defining characteristic of damage induced in the DNA by ionizing radiation (IR) is its clustered character that leads to the formation of complex lesions challenging the cellular repair mechanisms. The most widely investigated such complex lesion is the DNA double strand break (DSB). DSBs undermine chromatin stability and challenge the repair machinery because an intact template strand is lacking to assist restoration of integrity and sequence in the DNA molecule. Therefore, cells have evolved a sophisticated machinery to detect DSBs and coordinate a response on the basis of inputs from various sources. A central function of cellular responses to DSBs is the coordination of DSB repair. Two conceptually different mechanisms can in principle remove DSBs from the genome of cells of higher eukaryotes. Homologous recombination repair (HRR) uses as template a homologous DNA molecule and is therefore error-free; it functions preferentially in the S and G2 phases. Non-homologous end joining (NHEJ), on the other hand, simply restores DNA integrity by joining the two ends, is error prone as sequence is only fortuitously preserved and active throughout the cell cycle. The basis of DSB repair pathway choice remains unknown, but cells of higher eukaryotes appear programmed to utilize preferentially NHEJ. Recent work suggests that when the canonical DNA-PK dependent pathway of NHEJ (D-NHEJ), becomes compromised an alternative NHEJ pathway and not HRR substitutes in a quasi-backup function (B-NHEJ). Here, we outline aspects of DSB induction by IR and review the mechanisms of their processing in cells of higher eukaryotes. We place particular emphasis on backup pathways of NHEJ and summarize their increasing significance in various cellular processes, as well as their potential contribution to carcinogenesis.

  14. Double strand break induction and kinetics indicate preserved hypersensitivity in keratinocytes to subtherapeutic doses for 7weeks of radiotherapy.

    Science.gov (United States)

    Qvarnström, Fredrik; Simonsson, Martin; Nyman, Jan; Hermansson, Ingegerd; Book, Majlis; Johansson, Karl-Axel; Turesson, Ingela

    2017-01-01

    Previously we reported that hyper-radiosensitivity (HRS) was evidenced by quantifying DNA double strand break (DSB) foci in epidermis biopsies collected after delivering radiotherapeutic one and five dose fractions. The aim of this study was to determine whether HRS was preserved throughout a 7-week radiotherapy treatment, and also to examine the rate of foci decline and foci persistence between dose fractions. 42 patients with prostate cancer received 7-week fractionated radiotherapy treatment (RT) with daily dose fractions of 0.05-1.10Gy to the skin. Before RT, and at several times throughout treatment, skin biopsies (n=452) were collected at 30min, and 2, 3, 24, and 72h after dose fractions. DSB-foci markers, γH2AX and 53BP1, were labelled in epidermal keratinocytes with immunofluorescence and immunohistochemical staining. Foci were counted both with digital image analysis and manually. HRS in keratinocytes was evidenced by the dose-response relationships of DSB foci, observed throughout the treatment course, independent of sampling time and quantification method. Foci observed at 24h after dose fractions indicated considerable DSB persistence. Accordingly, foci significantly accumulated after 5 consecutive dose fractions. For doses below 0.3Gy, persistent foci could be observed even at 72h after damage induction. A comparison of γH2AX and 53BP1 quantifications in double-stained biopsies showed similar HRS dose-response relationships. These results represented the first evidence of preserved HRS, assessed by γH2AX- and 53BP1-labelled DSB foci, throughout a 7-week treatment course with daily repeated subtherapeutic dose fractions. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  15. Intubation conditions after rocuronium or succinylcholine for rapid sequence induction with alfentanil and propofol in the emergency patient

    DEFF Research Database (Denmark)

    Larsen, P B; Hansen, E G; Jacobsen, L S

    2005-01-01

    Background and objective: Previous studies mainly conducted on elective patients recommend doses of 0.9-1.2 mg kg[-1] rocuronium to obtain comparable intubation conditions with succinylcholine 1.0 mg kg[-1] after 60 s during a rapid-sequence induction. We decided to compare the overall intubating...... conditions of standard doses of rocuronium 0.6 mg kg[-1] and succinylcholine 1.0 mg kg[-1] during a strict rapid-sequence induction regimen including propofol and alfentanil. Methods: Male and female patients (ASA I-III) older than 17 yr scheduled for emergency abdominal or gynaecological surgery...... and with increased risk of pulmonary aspiration of gastric content were randomized to a rapid-sequence induction with succinylcholine 1.0 mg kg[-1] or rocuronium 0.6 mg kg[-1]. Patients with a predicted difficult airway were excluded. A senior anaesthesiologist 'blinded' for the randomization performed...

  16. Next Generation of Renewable Electricity Policy: How Rapid Change is Breaking Down Conventional Policy Categories

    Energy Technology Data Exchange (ETDEWEB)

    Couture, T. D. [E3 Analytics, Berlin (Germany); Jacobs, D. [International Energy Transition (IET), Boston, MA (United States); Rickerson, W. [Meister Consultants Group, Boston, MA (United States); Healey, V. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-02-01

    A number of policies have been used historically in order to stimulate the growth of the renewable electricity sector. This paper examines four of these policy instruments: competitive tendering, sometimes called renewable electricity auctions, feed-in tariffs, net metering and net billing, and tradable renewable energy certificates. In recent years, however, a number of changes to both market circumstances and to policy priorities have resulted in numerous policy innovations, including the emergence of policy hybrids. With no common language for these evolving policy mechanisms, policymakers have generally continued to use the same traditional policy labels, occasionally generating confusion as many of these new policies no longer look, or act, like their traditional predecessors. In reviewing these changes, this paper makes two separate but related claims: first, policy labels themselves are breaking down and evolving. As a result, policy comparisons that rely on the conventional labels may no longer be appropriate, or advisable. Second, as policymakers continue to adapt, we are in effect witnessing the emergence of the next generation of renewable electricity policies, a change that could have significant impacts on investment, as well as on market growth in both developed and developing countries.

  17. Heavy ion-induced lesions in DNA: A theoretical model for the initial induction of DNA strand breaks and chromatin breaks

    International Nuclear Information System (INIS)

    Schmidt, J.B.

    1993-01-01

    A theoretical model has been developed and used to calculate yields and spatial distributions of DNA strand breaks resulting from the interactions of heavy ions with chromatin in aqueous systems. The three dimensional spatial distribution of ionizing events has been modeled for charged particles as a function of charge and velocity. Chromatin has been modeled as a 30 nm diameter solenoid of nucleosomal DNA. The Monte Carlo methods used by Chatterjee et al. have been applied to DNA in a chromatin conformation. Refinements to their methods include: a combined treatment of primary and low energy (<2 keV) secondary electron interactions, an improved low energy delta ray model, and the combined simulation of direct energy deposition on the DNA and attack by diffusing hydroxyl radicals. Individual particle tracks are treated independently, which is assumed to be applicable to low fluence irradiations in which multiple particle effects are negligible. Single strand break cross section open-quotes hooksclose quotes seen in experiments at very high LET appear to be due to the collapsing radial extent of the track, as predicted in the open-quotes deep sieveclose quotes hypothesis proposed by Tobias et al. Spatial distributions of lesions produced by particles have been found to depend on chromatin structure. In the future, heavy ions may be used as a tool to probe the organization of DNA in chromatin. A Neyman A-binomial variation of the open-quotes cluster modelclose quotes for the distribution of chromatin breaks per irradiated cell has been theoretically tested. The model includes a treatment of the chromatin fragment detection technique's resolution, which places a limitation on the minimum size of fragments which can be detected. The model appears to fit some of the experimental data reasonably well. However, further experimental and theoretical refinements are desirable

  18. Rapid induction of lipid droplets in Chlamydomonas reinhardtii and Chlorella vulgaris by Brefeldin A.

    Directory of Open Access Journals (Sweden)

    Sangwoo Kim

    Full Text Available Algal lipids are the focus of intensive research because they are potential sources of biodiesel. However, most algae produce neutral lipids only under stress conditions. Here, we report that treatment with Brefeldin A (BFA, a chemical inducer of ER stress, rapidly triggers lipid droplet (LD formation in two different microalgal species, Chlamydomonas reinhardtii and Chlorella vulgaris. LD staining using Nile red revealed that BFA-treated algal cells exhibited many more fluorescent bodies than control cells. Lipid analyses based on thin layer chromatography and gas chromatography revealed that the additional lipids formed upon BFA treatment were mainly triacylglycerols (TAGs. The increase in TAG accumulation was accompanied by a decrease in the betaine lipid diacylglyceryl N,N,N-trimethylhomoserine (DGTS, a major component of the extraplastidic membrane lipids in Chlamydomonas, suggesting that at least some of the TAGs were assembled from the degradation products of membrane lipids. Interestingly, BFA induced TAG accumulation in the Chlamydomonas cells regardless of the presence or absence of an acetate or nitrogen source in the medium. This effect of BFA in Chlamydomonas cells seems to be due to BFA-induced ER stress, as supported by the induction of three homologs of ER stress marker genes by the drug. Together, these results suggest that ER stress rapidly triggers TAG accumulation in two green microalgae, C. reinhardtii and C. vulgaris. A further investigation of the link between ER stress and TAG synthesis may yield an efficient means of producing biofuel from algae.

  19. Induction of single-strand DNA breaks in human cells by H2O2 formed in near-uv (black light)-irradiated medium

    International Nuclear Information System (INIS)

    Wang, R.J.; Ananthaswamy, H.N.; Nixon, B.T.; Hartman, P.S.; Eisenstark, A.

    1980-01-01

    When Dulbecco's modified Eagle's medium (depleted of phenol red) was irradiated for up to 3 h by 4 to 5 W/m 2 black light, hydrogen peroxide (H 2 O 2 ) was produced. Generation of H 2 O 2 resulted from riboflavin-sensitized photooxidation of tryptophan and tyrosine. Reagent H 2 O 2 , or hydrogen peroxide generated in black light-exposed aqueous solutions containing riboflavin and tryptophan, induced 2 x 10 4 single-strand breaks per 10 16 daltons of DNA in intact, physiologically viable human D98/AH 2 cells. Concomitant with the single-strand breaks in the cells was loss of cellular reproductive viability. Two classes of photoproducts were identified: H 2 O 2 and non-H 2 O 2 . The H 2 O 2 component of the photoproducts was responsible for all the single-strand break induction but for only partial loss of reproductive viability. The non-H 2 O 2 photoproducts, accountable for the remainder of cell lethality, caused no single-strand breaks

  20. Evidence for induction of DNA double strand breaks in the bystander response to targeted soft X-rays in CHO cells

    International Nuclear Information System (INIS)

    Kashino, Genro; Prise, Kevin M.; Schettino, Giuseppe; Folkard, Melvyn; Vojnovic, Borivoj; Michael, Barry D.; Suzuki, Keiji; Kodama, Seiji; Watanabe, Masami

    2004-01-01

    This study investigated the role of DNA double strand breaks and DNA base damage in radiation-induced bystander responses in Chinese hamster ovary (CHO) cell lines. Two CHO repair-deficient clones, xrs5 (DNA double strand break repair-deficient) and EM9 (DNA base excision repair-deficient) were used in addition to the wild type (CHO). The Gray Cancer Institute ultrasoft X-ray microprobe is a powerful tool for investigating the bystander response, because it permits the irradiation of only a single nucleus of a cell, as reported previously. In order to investigate the bystander effect in each repair-deficient cell line, we irradiated a single cell within a population and scored the formation of micronuclei. When a single nucleus in the population was targeted with 1 Gy, elevated numbers of micronuclei were induced in the neighbouring unirradiated cells in the EM9 and xrs5 cell lines, whereas induction was not observed in CHO. The induction of micronuclei in xrs5 was significantly higher than that in EM9. Under these conditions, the surviving fraction in the neighbouring cells was significantly lower in xrs5 than in the other cell lines, showing a higher cell killing effect in xrs5. To confirm that bystander factors secreted from irradiated cells caused these effects, we carried out medium transfer experiments using conventional X-irradiation. Medium conditioned for 24 h with irradiated cells was transferred to unirradiated cells and elevated induction of micronuclei was observed in xrs5. These results suggest that DNA double strand breaks rather than base damage are caused by factors secreted in the medium from irradiated cells

  1. Rapid MCNP simulation of DNA double strand break (DSB) relative biological effectiveness (RBE) for photons, neutrons, and light ions.

    Science.gov (United States)

    Stewart, Robert D; Streitmatter, Seth W; Argento, David C; Kirkby, Charles; Goorley, John T; Moffitt, Greg; Jevremovic, Tatjana; Sandison, George A

    2015-11-07

    To account for particle interactions in the extracellular (physical) environment, information from the cell-level Monte Carlo damage simulation (MCDS) for DNA double strand break (DSB) induction has been integrated into the general purpose Monte Carlo N-particle (MCNP) radiation transport code system. The effort to integrate these models is motivated by the need for a computationally efficient model to accurately predict particle relative biological effectiveness (RBE) in cell cultures and in vivo. To illustrate the approach and highlight the impact of the larger scale physical environment (e.g. establishing charged particle equilibrium), we examined the RBE for DSB induction (RBEDSB) of x-rays, (137)Cs γ-rays, neutrons and light ions relative to γ-rays from (60)Co in monolayer cell cultures at various depths in water. Under normoxic conditions, we found that (137)Cs γ-rays are about 1.7% more effective at creating DSB than γ-rays from (60)Co (RBEDSB  =  1.017) whereas 60-250 kV x-rays are 1.1 to 1.25 times more efficient at creating DSB than (60)Co. Under anoxic conditions, kV x-rays may have an RBEDSB up to 1.51 times as large as (60)Co γ-rays. Fission neutrons passing through monolayer cell cultures have an RBEDSB that ranges from 2.6 to 3.0 in normoxic cells, but may be as large as 9.93 for anoxic cells. For proton pencil beams, Monte Carlo simulations suggest an RBEDSB of about 1.2 at the tip of the Bragg peak and up to 1.6 a few mm beyond the Bragg peak. Bragg peak RBEDSB increases with decreasing oxygen concentration, which may create opportunities to apply proton dose painting to help address tumor hypoxia. Modeling of the particle RBE for DSB induction across multiple physical and biological scales has the potential to aid in the interpretation of laboratory experiments and provide useful information to advance the safety and effectiveness of hadron therapy in the treatment of cancer.

  2. A new rapid kindling variant for induction of cortical epileptogenesis in freely moving rats

    Directory of Open Access Journals (Sweden)

    Juan Carlos Morales

    2014-07-01

    Full Text Available Kindling, one of the most used models of experimental epilepsy is based on daily electrical stimulation in several brain structures. Unlike the classic or slow kindling protocols (SK, the rapid kindling types (RK described until now require continuous stimulation at suprathreshold intensities applied directly to the same brain structure used for subsequent electrophysiological and inmunohistochemical studies, usually the hippocampus. However, the cellular changes observed in these rapid protocols, such as astrogliosis and neuronal loss, could be due to experimental manipulation more than to epileptogenesis-related alterations. Here, we developed a new RK protocol in order to generate an improved model of temporal lobe epilepsy (TLE which allows gradual progression of the epilepsy as well as obtaining an epileptic hippocampus, thus avoiding direct surgical manipulation and electric stimulation over this structure. This new protocol consists of basolateral amygdala (BLA stimulation with 10 trains of biphasic pulses (10s;50Hz per day with 20 minutes-intervals, during 3 consecutive days, using a subconvulsive and subthreshold intensity, which guarantees tissue integrity. The progression of epileptic activity was evaluated in freely moving rats through EEG recordings from cortex and amygdala, accompanied with synchronized video recordings. Moreover, we assessed the effectiveness of RK protocol and the establishment of epilepsy by evaluating cellular alterations of hippocampal slices from kindled rats. RK protocol induced convulsive states similar to SK protocols but in 3 days, with persistently lowered threshold to seizure induction and epileptogenic-dependent cellular changes in amygdala projection areas. We concluded that this novel RK protocol introduces a new variant of the chronic epileptogenesis models in freely moving rats, which is faster, highly reproducible and causes minimum cell damage with respect to that observed in other experimental

  3. Electromagnetic induction heating for single crystal graphene growth: morphology control by rapid heating and quenching

    Science.gov (United States)

    Wu, Chaoxing; Li, Fushan; Chen, Wei; Veeramalai, Chandrasekar Perumal; Ooi, Poh Choon; Guo, Tailiang

    2015-03-01

    The direct observation of single crystal graphene growth and its shape evolution is of fundamental importance to the understanding of graphene growth physicochemical mechanisms and the achievement of wafer-scale single crystalline graphene. Here we demonstrate the controlled formation of single crystal graphene with varying shapes, and directly observe the shape evolution of single crystal graphene by developing a localized-heating and rapid-quenching chemical vapor deposition (CVD) system based on electromagnetic induction heating. Importantly, rational control of circular, hexagonal, and dendritic single crystalline graphene domains can be readily obtained for the first time by changing the growth condition. Systematic studies suggest that the graphene nucleation only occurs during the initial stage, while the domain density is independent of the growth temperatures due to the surface-limiting effect. In addition, the direct observation of graphene domain shape evolution is employed for the identification of competing growth mechanisms including diffusion-limited, attachment-limited, and detachment-limited processes. Our study not only provides a novel method for morphology-controlled graphene synthesis, but also offers fundamental insights into the kinetics of single crystal graphene growth.

  4. Evidence for induction of DNA double strand breaks in the bystander response to targeted soft X-rays in repair deficient CHO cells

    International Nuclear Information System (INIS)

    Kashino, Genro; Suzuki, Keiji; Prise, K.M.

    2005-01-01

    Evidence is accumulating that irradiated cells produce some signals which interact with non-exposed cells in the same population. Here, we analysed the mechanism of such a bystander effect from targeted cells to non-targeted cells. Firstly, in order to investigate the bystander effect in Chinese hamster ovary (CHO) cell lines we irradiated a single cell within a population and scored the formation of micronuclei. When a single nucleus in the population, of double strand break repair deficient xrs5 cells, was targeted with 1 Gy of Al-K soft X-rays, elevated numbers of micronuclei were induced in the neighbouring unirradiated cells. The induction of micronuclei was also observed when conditioned medium was transferred from irradiated to non-irradiated xrs5 cells. These results suggest that DNA double strand breaks are caused by factors secreted in the medium from irradiated cells. To clarify the involvements of radical species in the bystander response, cells were treated with 0.5%DMSO 1 hour before irradiation and then bystander effects were estimated in xrs5 cells. The results showed clearly that DMSO treatment during X-irradiation suppress the induction of micronuclei in bystander xrs5 cells, when conditioned medium was transferred from irradiated xrs5 cells. Therefore, it is suggested that radical species induced by ionizing radiation are important for producing bystander signals. (author)

  5. Differential Involvement of β-Glucosidases from Hypocrea jecorina in Rapid Induction of Cellulase Genes by Cellulose and Cellobiose

    Science.gov (United States)

    Zhou, Qingxin; Xu, Jintao; Kou, Yanbo; Lv, Xinxing; Zhang, Xi; Zhao, Guolei; Zhang, Weixin; Chen, Guanjun

    2012-01-01

    Appropriate perception of cellulose outside the cell by transforming it into an intracellular signal ensures the rapid production of cellulases by cellulolytic Hypocrea jecorina. The major extracellular β-glucosidase BglI (CEL3a) has been shown to contribute to the efficient induction of cellulase genes. Multiple β-glucosidases belonging to glycosyl hydrolase (GH) family 3 and 1, however, exist in H. jecorina. Here we demonstrated that CEL1b, like CEL1a, was an intracellular β-glucosidase displaying in vitro transglycosylation activity. We then found evidence that these two major intracellular β-glucosidases were involved in the rapid induction of cellulase genes by insoluble cellulose. Deletion of cel1a and cel1b significantly compromised the efficient gene expression of the major cellulase gene, cbh1. Simultaneous absence of BglI, CEL1a, and CEL1b caused the induction of the cellulase gene by cellulose to further deteriorate. The induction defect, however, was not observed with cellobiose. The absence of the three β-glucosidases, rather, facilitated the induced synthesis of cellulase on cellobiose. Furthermore, addition of cellobiose restored the productive induction on cellulose in the deletion strains. The results indicate that the three β-glucosidases may not participate in transforming cellobiose beyond hydrolysis to provoke cellulase formation in H. jecorina. They may otherwise contribute to the accumulation of cellobiose from cellulose as inducing signals. PMID:23002106

  6. Comparison of plastic single-use and metal reusable laryngoscope blades for orotracheal intubation during rapid sequence induction of anesthesia.

    Science.gov (United States)

    Amour, Julien; Marmion, Frédéric; Birenbaum, Aurélie; Nicolas-Robin, Armelle; Coriat, Pierre; Riou, Bruno; Langeron, Olivier

    2006-01-01

    Plastic single-use laryngoscope blades are inexpensive and carry a lower risk of infection compared with metal reusable blades, but their efficiency during rapid sequence induction remains a matter of debate. The authors therefore compared plastic and metal blades during rapid sequence induction in a prospective randomized trial. Two hundred eighty-four adult patients undergoing general anesthesia requiring rapid sequence induction were randomly assigned on a weekly basis to either plastic single-use or reusable metal blades (cluster randomization). After induction, a 60-s period was allowed to complete intubation. In the case of failed intubation, a second attempt was performed using metal blade. The primary endpoint of the study was the rate of failed intubations, and the secondary endpoint was the incidence of complications (oxygen desaturation, lung aspiration, and oropharynx trauma). Both groups were similar in their main characteristics, including risk factors for difficult intubation. On the first attempt, the rate of failed intubation was significantly increased in plastic blade group (17 vs. 3%; P < 0.01). In metal blade group, 50% of failed intubations were still difficult after the second attempt. In plastic blade group, all initial failed intubations were successfully intubated using metal blade, with an improvement in Cormack and Lehane grade. There was a significant increase in the complication rate in plastic group (15 vs. 6%; P < 0.05). In rapid sequence induction of anesthesia, the plastic laryngoscope blade is less efficient than a metal blade and thus should not be recommended for use in this clinical setting.

  7. [Rocuronium and sugammadex in emergency medicine: requirements of a muscle relaxant for rapid sequence induction].

    Science.gov (United States)

    Luxen, J; Trentzsch, H; Urban, B

    2014-04-01

    The required characteristics of neuromuscular blockers for rapid sequence induction (RSI) are clearly defined: nearly immediate effectiveness and short duration of effect. These demands are not only necessary for ideal conditions of quick endotracheal intubation without mask-bag intermediate ventilation but are also essential to enable a quick return to sufficient spontaneous breathing in case of a cannot intubate cannot ventilate situation. Until recently only succinylcholine had these characteristics; however, a considerable number of dangerous side effects and contraindications had to be accepted. In 1996, rocuronium was introduced, which was capable of immediately establishing good intubation conditions similar to succinylcholine. However, the median duration of effect is 45-60 min and it therefore contains a risk if the patient cannot be ventilated and oxygenated. Therefore, rocuronium is considered a good alternative but not a complete substitute for succinylcholine. The introduction of sugammadex in 2008 for quick reversal of rocuronium changed matters. Comparative studies from the past 4 years dealing with rocuronium/sugammadex versus uccinylcholine in RSI showed that rocuronium and sugammadex combined enabled a significantly faster return to sufficient spontaneous ventilation in emergency situations and also proved that the use of rocuronium significantly reduced the degree of desaturation during the interval between injection and ventilation postintubation. rocuronium used in hospital is a very good substitute for succinylcholine as a neuromuscular blocker during RSI as long as sugammadex is at hand for reversal. It remains to be considered that in a situation with severe problems of the airway and breathing, which are the main preclinical indications for intubation, a forward strategy for ventilation of the patient is the only acceptable way in most cases and the return to spontaneous breathing is not an alternative. Therefore, the value of sugammadex

  8. Early induction of NRF2 antioxidant pathway by RHBDF2 mediates rapid cutaneous wound healing.

    Science.gov (United States)

    Hosur, Vishnu; Burzenski, Lisa M; Stearns, Timothy M; Farley, Michelle L; Sundberg, John P; Wiles, Michael V; Shultz, Leonard D

    2017-04-01

    Rhomboid family protein RHBDF2, an upstream regulator of the epidermal growth factor (EGF) receptor signaling, has been implicated in cutaneous wound healing. However, the underlying molecular mechanisms are still emerging. In humans, a gain-of-function mutation in the RHBDF2 gene accelerates cutaneous wound healing in an EGFR-dependent manner. Likewise, a gain-of-function mutation in the mouse Rhbdf2 gene (Rhbdf2 cub/cub ) shows a regenerative phenotype (rapid ear-hole closure) resulting from constitutive activation of the EGFR pathway. Because the RHBDF2-regulated EGFR pathway is relevant to cutaneous wound healing in humans, we used Rhbdf2 cub/cub mice to investigate the biological networks and pathways leading to accelerated ear-hole closure, with the goal of identifying therapeutic targets potentially effective in promoting wound healing in humans. Comparative transcriptome analysis of ear pinna tissue from Rhbdf2 cub/cub and Rhbdf2 +/+ mice at 0h, 15min, 2h, and 24h post-wounding revealed an early induction of the nuclear factor E2-related factor 2 (NRF2)-mediated anti-oxidative pathway (0h and 15min), followed by the integrin-receptor aggregation pathway (2h) as early-stage events immediately and shortly after wounding in Rhbdf2 cub/cub mice. Additionally, we observed genes enriched for the Fc fragment of the IgG receptor IIIa (FCGR3A)-mediated phagocytosis pathway 24h post-wounding. Although cutaneous wound repair in healthy individuals is generally non-problematic, it can be severely impaired due to aging, diabetes, and chronic inflammation. This study suggests that activation of the NRF2-antioxidant pathway by rhomboid protein RHBDF2 might be beneficial in treating chronic non-healing wounds. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Induction of DNA damage in γ-irradiated nuclei stripped of nuclear protein classes: differential modulation of double-strand break and DNA-protein crosslink formation

    International Nuclear Information System (INIS)

    Xue, L.-Y.; Friedman, L.R.; Oleinick, N.L.; Chiu, S.-M.

    1994-01-01

    The influence of chromatin proteins on the induction of DNA double-strand breaks (dsb) and DNA-protein crosslinks (dpc) by γ-radiation was investigated. Low molecular weight non-histone proteins and classes of histones were extracted with increasing concentrations of NaC1, whereas nuclear matrix proteins were not extractable even by 2.0 M NACl. The yield of dsb increased with progressive removal of proteins from chromatin. The data support our previous conclusion that nuclear matrix protein rather than the majority of the histones are the predominant substrates for dpc production, although the involvement of a subset of tightly bound histones (H3 and H4) has not been excluded. This finding demonstrates that chromatin proteins can differentially modify the yield of two types of radiation-induced DNA lesions. (author)

  10. Cytotoxicity and genotoxicity of a monazite component: lanthanum effects on the viability and induction of breaks in the DNA of human lymphocytes

    International Nuclear Information System (INIS)

    Paiva, Amanda Valle de Almeida

    2007-01-01

    The Monazite is a mineral extracted from open mines. It is constituted by lanthanum element aggregated with cerium, yttrium and thorium [(Ce, La, Y, Th)PO 4 ]. Lanthanum (La) is a rare-earth metal with applications in agriculture, industry and medicine. Since lanthanides and their compounds show a broad spectrum of applications there is an increased risk of incorporation in human. Inhalation of aerosols containing La is the main route of incorporation in workers exposed to several chemical forms of La. Herein, we examined the effect of lanthanum nitrate - La(NO 3 ) 3 in human lymphocytes. JURKAT cells and human peripheral lymphocytes (HPL) were used to evaluate the effect of La(NO 3 ) 3 on viability (apoptosis or necrosis) and DNA strand breaks induction or/and alkali-labile sites (ALS). We demonstrate that La has a cytotoxic and genotoxic effect on both cell lines. The results indicate that necrosis is the pathway by which La(NO 3 ) 3 induces cytotoxicity. The vitamin E is able to diminish DNA strand breaks induced by La(NO 3 ) 3 suggesting that reactive oxygen species (ROS) may be involved in the genotoxic process. (author)

  11. Influence of different iodinated contrast media on the induction of DNA double-strand breaks after in vitro X-ray irradiation.

    Science.gov (United States)

    Deinzer, Christoph K W; Danova, Daniela; Kleb, Beate; Klose, Klaus J; Heverhagen, Johannes T

    2014-01-01

    The objective of this work was to examine differences in DNA double-strand break induction in peripheral blood lymphocytes after in vitro X-ray irradiation between iodinated contrast agents. Four different iodinated X-ray contrast agents--three of them with two different iodine concentrations--and mannitol (negative control; concentration of 150 mg mannitol per ml blood) were pipetted into blood samples so that there was a concentration of 0, 7.5 or 15 mg of iodine per ml blood in the samples. Negative controls without contrast medium (0 mg of iodine per ml blood) were also processed for every irradiation dose. The tubes were exposed to 0, 20 or 500 mGy in vitro X-ray irradiation. After that, the lymphocytes were separated by using density-gradient centrifugation. Fluorescence microscopy was applied to determine the average number of γH2AX-foci per lymphocyte in the presence or absence of different contrast media or mannitol. Differences in the number of γH2AX-foci were statistically analysed by one-way ANOVA and post-hoc Tukey's honestly significant difference test. Iodinated contrast agents led to a statistically significant increase in DNA double-strand breaks after in vitro irradiation. This effect increased statistically significant with rising radiation dose and appeared independent of the contrast agent used (iopromid, iodixanol, iomeprol, iopamidol). A statistically significant difference in DNA damage between the different tested contrast agents was not found. Therefore, the increase in DNA double-strand breaks depends solely on the amount of iodine applied. For evaluation of clinical consequences, our findings could be tested in further animal studies. Copyright © 2014 John Wiley & Sons, Ltd.

  12. Rapid expansion of preexisting nonleukemic hematopoietic clones frequently follows induction therapy for de novo AML.

    Science.gov (United States)

    Wong, Terrence N; Miller, Christopher A; Klco, Jeffery M; Petti, Allegra; Demeter, Ryan; Helton, Nichole M; Li, Tiandao; Fulton, Robert S; Heath, Sharon E; Mardis, Elaine R; Westervelt, Peter; DiPersio, John F; Walter, Matthew J; Welch, John S; Graubert, Timothy A; Wilson, Richard K; Ley, Timothy J; Link, Daniel C

    2016-02-18

    There is interest in using leukemia-gene panels and next-generation sequencing to assess acute myelogenous leukemia (AML) response to induction chemotherapy. Studies have shown that patients with AML in morphologic remission may continue to have clonal hematopoiesis with populations closely related to the founding AML clone and that this confers an increased risk of relapse. However, it remains unknown how induction chemotherapy influences the clonal evolution of a patient's nonleukemic hematopoietic population. Here, we report that 5 of 15 patients with genetic clearance of their founding AML clone after induction chemotherapy had a concomitant expansion of a hematopoietic population unrelated to the initial AML. These populations frequently harbored somatic mutations in genes recurrently mutated in AML or myelodysplastic syndromes and were detectable at very low frequencies at the time of AML diagnosis. These results suggest that nonleukemic hematopoietic stem and progenitor cells, harboring specific aging-acquired mutations, may have a competitive fitness advantage after induction chemotherapy, expand, and persist long after the completion of chemotherapy. Although the clinical importance of these "rising" clones remains to be determined, it will be important to distinguish them from leukemia-related populations when assessing for molecular responses to induction chemotherapy. © 2016 by The American Society of Hematology.

  13. The effect of 111In radionuclide distance and auger electron energy on direct induction of DNA double-strand breaks: a Monte Carlo study using Geant4 toolkit.

    Science.gov (United States)

    Piroozfar, Behnaz; Raisali, Gholamreza; Alirezapour, Behrouz; Mirzaii, Mohammad

    2018-04-01

    In this study, the effect of 111 In position and Auger electron energy on direct induction of DSBs was investigated. The Geant4-DNA simulation toolkit was applied using a simple B-DNA form extracted from PDBlib library. First, the simulation was performed for electrons with energies of 111 In and equal emission probabilities to find the most effective electron energies. Then, 111 In Auger electrons' actual spectrum was considered and their contribution in DSB induction analysed. The results showed that the most effective electron energy is 183 eV, but due to the higher emission probability of 350 eV electrons, most of the DSBs were induced by the latter electrons. Also, it was observed that most of the DSBs are induced by electrons emitted within 4 nm of the central axis of the DNA and were mainly due to breaks with <4 base pairs distance in opposing strands. Whilst, when 111 In atoms are very close to the DNA, 1.3 DSBs have been obtained per decay of 111 In atoms. The results show that the most effective Auger electrons are the 350 eV electrons from 111 In atoms with <4 nm distance from the central axis of the DNA which induce ∼1.3 DSBs per decay when bound to the DNA. This value seems reasonable when compared with the reported experimental data.

  14. Heterochromatinization associated with cell differentiation as a model to study DNA double strand break induction and repair in the context of higher-order chromatin structure

    International Nuclear Information System (INIS)

    Falk, Martin; Lukášová, Emilie; Štefančíková, Lenka; Baranová, Elena; Falková, Iva; Ježková, Lucie; Davídková, Marie; Bačíková, Alena; Vachelová, Jana; Michaelidesová, Anna; Kozubek, Stanislav

    2014-01-01

    Cell differentiation is associated with extensive gene silencing, heterochromatinization and potentially decreasing need for repairing DNA double-strand breaks (DSBs). Differentiation stages of blood cells thus represent an excellent model to study DSB induction, repair and misrepair in the context of changing higher-order chromatin structure. We show that immature granulocytes form γH2AX and 53BP1 foci, contrary to the mature cells; however, these foci colocalize only rarely and DSB repair is inefficient. Moreover, specific chromatin structure of granulocytes probably influences DSB induction. - Highlights: ► DSB repair is absent in mature granulocytes with condensed chromatin. ► Repair proteins and γH2AX appear in immature stages but rarely colocalize. ► γH2AX persist long times in these cells and DSB repair is inefficient. ► Even though, γH2AX foci “move” out of the dense chromatin. ► 53BP1 enters HP1β domains only after their decondensation

  15. Early cytokine modulation after the rapid induction phase of sublingual immunotherapy with mite monomeric allergoids.

    Science.gov (United States)

    Di Gioacchino, M; Perrone, A; Petrarca, C; Di Claudio, F; Mistrello, G; Falagiani, P; Dadorante, V; Verna, N; Braga, M; Ballone, E; Cavallucci, E

    2008-01-01

    The influence of different treatment schedules of sublingual immunotherapy (SLIT) in activating IL-10-producing T-cells, crucial in inducing allergen-specific tolerance, is not completely understood. The present work was designed to evaluate allergen driven interleukin release by mononuclear cells in the early phase of SLIT, after application of different induction schemes. Twenty mite-allergic patients were enrolled, 10 (group A) treated with a traditional 98 day induction scheme and 10 (group B) with a 16 day scheme with monomeric allergoid vaccine. At the end of the induction phase, the cumulative doses taken by group A and group B patients were equivalent to 50.5 and 50.3 microg of mite group 1 allergens, respectively. The release of Th1-, Th2- and Treg-related interleukins was assessed in culture supernatants of 5 microg/ml Der-p1-stimulated mononuclear cells, isolated before and after the induction phases. No relevant treatment-related side effects were observed. Interleukin release was similar in the two groups at the enrolment. Non-stimulated and Der p 1 stimulated release of studied cytokines was similar in the two groups at enrolment. Der p 1 stimulation significantly increased IL-10 release (pallergoids are utilized.

  16. Metallothionein mRNA induction is correlated with the decrease of DNA strand breaks in cadmium exposed zebra mussels.

    Science.gov (United States)

    Vincent-Hubert, Françoise; Châtel, Amélie; Gourlay-Francé, Catherine

    2014-05-15

    We have previously shown that cadmium (Cd) and benzo[a]pyrene (BaP) induced early DNA damages in zebra mussels, and that the level of DNA strand breaks (SB) returned to a basal level after 3 days of exposure to Cd. The aim of the present study was to go further in the mechanisms of Cd and BaP detoxification. For that purpose, expression of genes encoding for metallothionein (MT), aryl hydrocarbon receptor (AHR), P-gp, catalase, glutathione S-transferase and heat shock protein 70 (HSP70) proteins have been measured using RT-qPCR. Data reported here show that Cd is a strong inducer of MT and HSP70 genes, and that BaP is a strong inducer of P-gp and AHR genes. Exposure to Cd and BaP resulted in moderate changes in antioxidant enzymes mRNA. Since the increase of MT mRNA occurred when the DNA SB level returned to its basal level, we can suggest that MT is implicated in cadmium detoxification. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Induction of DNA-strand breaks after X- irradiation in murine bone cells of various differentiation capacities

    Science.gov (United States)

    Lau, P.; Hellweg, C. E.; Kirchner, S.; Arenz, A.; Baumstark-Khan, C.; Horneck, G.

    Bone loss resulting from long-duration space flight is a well known medical risk for space travellers, as a weakened skeleton is more susceptible to bone fractures. In addition to weightlessness the astronaut is also exposed to cosmic ionizing radiation. In order to elucidate changes in bone cell metabolism by ionizing radiation, a ground-based bone cell model has been developed. This model consists of a bunch of immortalized murine osteocyte, osteoblast and pre-osteoblast cell lines representing discrete stages of differentiation: The osteocyte cell line MLO-Y4 (obtained from L. Bonewald, Kansas City, USA), the osteoblast cell line OCT-1 (obtained from D. Chen, San Antonio, USA), and the subclones 4 and 24 of the osteoblast cell line MC3T3-E1 (obtained from ATCC, Manassas, Virginia, USA). Regarding their growth properties, MLO-Y4 cells show the highest growth velocity with a doubling time of 15.8 h. The osteoblast cell line OCT-1 has a doubling time of 27.3 h. The respective values for MC3T3-E1 subclone 24 and S4 are 90.5 h and 51.6 h. To investigate the stage of differentiation, the expression of alkaline phosphatase, of osteocalcin and of E11 was examined. Survival after X-ray exposure was determined using the colony forming ability test. The resulting dose-effect relationships revealed significant differences. The parameter D0 of the survival curves ranges between 1.8 Gy for OCT-1, 1.9 Gy for MLO-Y4, 2.0 Gy for subclone 24 and 2,3 Gy for subclone 4. The quantitative acquisition of DNA-strand breaks was performed by Fluorescent Analysis of DNA-Unwinding (FADU). The results can be correlated with the corresponding survival curve. In conclusion, the cell lines with higher differentiation levels are less sensitive to radiation when compared to the lower differentiated osteoblast cell lines.

  18. Rapid Induction of Aldosterone Synthesis in Cultured Neonatal Rat Cardiomyocytes under High Glucose Conditions

    Directory of Open Access Journals (Sweden)

    Masami Fujisaki

    2013-01-01

    Full Text Available In addition to classical adrenal cortical biosynthetic pathway, there is increasing evidence that aldosterone is produced in extra-adrenal tissues. Although we previously reported aldosterone production in the heart, the concept of cardiac aldosterone synthesis remains controversial. This is partly due to lack of established experimental models representing aldosterone synthase (CYP11B2 expression in robustly reproducible fashion. We herein investigated suitable conditions in neonatal rat cardiomyocytes (NRCMs culture system producing CYP11B2 with considerable efficacy. NRCMs were cultured with various glucose doses for 2–24 hours. CYP11B2 mRNA expression and aldosterone concentrations secreted from NRCMs were determined using real-time PCR and enzyme immunoassay, respectively. We found that suitable conditions for CYP11B2 induction included four-hour incubation with high glucose conditions. Under these particular conditions, CYP11B2 expression, in accordance with aldosterone secretion, was significantly increased compared to those observed in the cells cultured under standard-glucose condition. Angiotensin II receptor blocker partially inhibited this CYP11B2 induction, suggesting that there is local renin-angiotensin-aldosterone system activation under high glucose conditions. The suitable conditions for CYP11B2 induction in NRCMs culture system are now clarified: high-glucose conditions with relatively brief period of culture promote CYP11B2 expression in cardiomyocytes. The current system will help to accelerate further progress in research on cardiac tissue aldosterone synthesis.

  19. Cellular and subcellular effect of heavy ions: A comparison of the induction of strand breaks and chromosomal aberration with the incidence of inactivation and mutation

    International Nuclear Information System (INIS)

    Kraft, G.; Kraft-Weyrather, W.; Ritter, S.; Scholz, M.; Stanton, J.

    1988-10-01

    Radiobiological effects of heavy charged particles are compared for a large variety of ions from Helium to Uranium and energies between 1 and 1000 MeV/u which correspond to LET values between 10 and 16000 keV/μm. The different cross section for the induction of strand breaks and chromosomal aberrations as well as for inactivation and mutation induction exhibit striking similarities when compared as function of the linear energy transfer (LET). At LET values below 100 keV/μm all data points of one specific effect form one single curve as a function of LET, independent of the atomic number of the ion. In this LET range, the biological effects are independent from the particle energy or track structure and depend only on the energy transfer. Therefore, LET is a good parameter in tis regime. For LET values greater than 100 keV/μm, the curves for the different ions separate from the common curve in order of increasing atomic numbers. In this regime LET is no longer a good parameter and the physical parameters of the formation of particle tracks are important. The similarity of the σ-LET curves for different endpoints indicates that the 'hook-structure' is produced by physical and chemical effects which occur before the biologically relevant lesions are formed. However, from the existing data of biological effects, it can be concluded that the efficiencies for cell killing are always smaller than those extrapolated from X-ray data on the basis of the energy deposition only. Therefore, cells which are directly hit by an HZE particle are not killed and undergo a finite risk of mutation and transformation. (orig.)

  20. Induction of strand breaks in DNA films by low energy electrons and soft X-ray under nitrous oxide atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Alizadeh, Elahe, E-mail: Elahe.Alizadeh@USherbrooke.ca [Groupe en science des radiations, Departement de medecine nucleaire et radiobiologie, Faculte de medecine et des sciences de la sante, Universite de Sherbrooke, Sherbrooke, J1H 5N4 (Canada); Sanche, Leon, E-mail: Leon.Sanche@USherbrooke.ca [Groupe en science des radiations, Departement de medecine nucleaire et radiobiologie, Faculte de medecine et des sciences de la sante, Universite de Sherbrooke, Sherbrooke, J1H 5N4 (Canada)

    2012-01-15

    Five-monolayer (5 ML) plasmid DNA films deposited on glass and tantalum substrates were exposed to Al K{sub {alpha}} X-rays of 1.5 keV under gaseous nitrous oxide (N{sub 2}O) at atmospheric pressure and temperature. Whereas the damage yields for DNA deposited on glass are due to soft X-rays, those arising from DNA on tantalum are due to both the interaction of low energy photoelectrons from the metal and X-rays. Then, the differences in the yields of damage on glass and tantalum substrates, essentially arises from interaction of essentially low-energy electrons (LEEs) with DNA molecules and the surrounding atmosphere. The G-values (i.e., the number of moles of product per Joule of energy absorbed) for DNA strand breaks induced by LEEs (G{sub LEE}) and the lower limit of G-values for soft X-ray photons (G{sub XL}) were calculated and the results compared to those from previous studies under atmospheric conditions and other ambient gases, such as N{sub 2} and O{sub 2}. Under N{sub 2}O, the G-values for loss of supercoiled DNA are 103{+-}15 nmol/J for X-rays, and 737{+-}110 nmol/J for LEEs. Compared to corresponding values in an O{sub 2} atmosphere, the effectiveness of X-rays to damage DNA in N{sub 2}O is less, but the G value for LEEs in N{sub 2}O is more than twice the corresponding value for an oxygenated environment. This result indicates a higher effectiveness for LEEs relative to N{sub 2} and O{sub 2} environments in causing SSB and DSB in an N{sub 2}O environment. Thus, the previously observed radiosensitization of cells by N{sub 2}O may not be only due to OH{sup {center_dot}} radicals but also to the reaction of LEE with N{sub 2}O molecules near DNA. The previous experiments with N{sub 2} and O{sub 2} and the present one demonstrate the possibility to investigate damage induced by LEEs to biomolecules under various types of surrounding atmospheres. - Highlights: > A completely different and new approach is applied to investigate the radiation chemistry of N

  1. A novel model for rapid induction of apoptosis in spiral ganglions of mice.

    Science.gov (United States)

    Lee, Ji Eun; Nakagawa, Takayuki; Kim, Tae Soo; Iguchi, Fukuichiro; Endo, Tsuyoshi; Dong, Youyi; Yuki, Kazuo; Naito, Yasushi; Lee, Sang Heun; Ito, Juichi

    2003-06-01

    The survival of the spiral ganglion (SG) is a critical issue in preservation of hearing. Research on topics related to this issue requires a mouse experimental model because such a model has advantages including use of genetic information and knockout or "knockin" mice. Thus, the aim of the study was to establish a mouse model for induction of apoptosis of SG neurons with a definite time course. Laboratory study using experimental animals. C57BL/6 mice were used as experimental animals and were subjected to direct application of cisplatin into the inner ear. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay and immunostaining for Neurofilament 200-kD (NF) and peripherin were used for analysis of SG degeneration. In addition, generation of peroxynitrite in affected spiral ganglions was examined by immunostaining for nitrotyrosine. Cellular location of activated caspase-9 and cytochrome-c in dying SG neurons were examined for analysis of cell death pathway. The TUNEL assay and immunohistochemical analysis for NF and peripherin indicated that type I neurons in spiral ganglions were deleted through the apoptotic pathway over time. Spiral ganglion neurons treated with cisplatin exhibited expression of nitrotyrosine, indicating induction of peroxynitrite by cisplatin. In dying SG neurons, expression of activated caspase-9 and translocation of cytochrome-c from mitochondria to cytoplasm were observed, indicating the mitochondrial pathway of apoptosis. The predictable fashion of induction of apoptosis in SG neurons over a well-defined time course in the model in the study will aid studies of the molecular mechanism of cell death and elucidation of a strategy for prevention of SG degeneration.

  2. DNA double-strand break and apoptosis induction in human lymphocytes in different cycle cell phases by 60Co gamma rays and Bragg peak protons of a medical beam

    International Nuclear Information System (INIS)

    Khachenkova, A.A.; Boreyko, A.V.; Mozhaeva, A.V.; Chausov, V.N.; Ravnachka, I.I.; Amov, I.; Tiunchik, S.I.

    2009-01-01

    A comparative analysis is made of the regularities in the formation of DNA double-strand break and apoptosis induction in peripheral human blood lymphocytes in different cell cycle phases after 60 Co gamma and extended Bragg peak proton irradiation. It is shown that the formation of apoptotic cells in a lymphocyte population increases linearly in all the cell cycle stages after proton irradiation. The maximal DNA double-strand break and apoptosis yield in lymphocytes is observed in the S phase of the cell cycle

  3. Vasoactive intestinal polypeptide excites medial pontine reticular formation neurons in the brainstem rapid eye movement sleep-induction zone

    DEFF Research Database (Denmark)

    Kohlmeier, Kristi Anne; Reiner, P B

    1999-01-01

    Although it has long been known that microinjection of the cholinergic agonist carbachol into the medial pontine reticular formation (mPRF) induces a state that resembles rapid eye movement (REM) sleep, it is likely that other transmitters contribute to mPRF regulation of behavioral states. A key...... candidate is the peptide vasoactive intestinal polypeptide (VIP), which innervates the mPRF and induces REM sleep when injected into this region of the brainstem. To begin understanding the cellular mechanisms underlying this phenomenon, we examined the effects of VIP on mPRF cells using whole-cell patch...... conclude that VIP excites mPRF neurons by activation of a sodium current. This effect is mediated at least in part by G-protein stimulation of adenylyl cyclase, cAMP, and protein kinase A. These data suggest that VIP may play a physiological role in REM induction by its actions on mPRF neurons....

  4. Rapid Access to β-Trifluoromethyl-Substituted Ketones: Harnessing Inductive Effects in Wacker-Type Oxidations of Internal Alkenes

    KAUST Repository

    Lerch, Michael M.; Morandi, Bill; Wickens, Zachary K.; Grubbs, Robert H.

    2014-01-01

    We present a practical trifluoromethyl-directed Wacker-type oxidation of internal alkenes that enables rapid access to β-trifluoromethyl-substituted ketones. Allylic trifluoromethyl-substituted alkenes bearing a wide range of functional groups can be oxidized in high yield and regioselectivity. The distance dependence of the regioselectivity was established by systematic variation of the number of methylene units between the double bond and the trifluoromethyl group. The regioselectivity enforced by traditional directing groups could even be reversed by introduction of a competing trifluoromethyl group. Besides being a new powerful synthetic method to prepare fluorinated molecules, this work directly probes the role of inductive effects on nucleopalladation events. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Rapid Access to β-Trifluoromethyl-Substituted Ketones: Harnessing Inductive Effects in Wacker-Type Oxidations of Internal Alkenes

    KAUST Repository

    Lerch, Michael M.

    2014-07-18

    We present a practical trifluoromethyl-directed Wacker-type oxidation of internal alkenes that enables rapid access to β-trifluoromethyl-substituted ketones. Allylic trifluoromethyl-substituted alkenes bearing a wide range of functional groups can be oxidized in high yield and regioselectivity. The distance dependence of the regioselectivity was established by systematic variation of the number of methylene units between the double bond and the trifluoromethyl group. The regioselectivity enforced by traditional directing groups could even be reversed by introduction of a competing trifluoromethyl group. Besides being a new powerful synthetic method to prepare fluorinated molecules, this work directly probes the role of inductive effects on nucleopalladation events. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Induction and Rejoining of DNA Double Strand Breaks Assessed by H2AX Phosphorylation in Melanoma Cells Irradiated with Proton and Lithium Beams

    International Nuclear Information System (INIS)

    Ibanez, Irene L.; Bracalente, Candelaria; Molinari, Beatriz L.; Palmieri, Monica A.; Policastro, Lucia; Kreiner, Andres J.; Burlon, Alejandro A.; Valda, Alejandro; Navalesi, Daniela; Davidson, Jorge; Davidson, Miguel; Vazquez, Monica; Ozafran, Mabel; Duran, Hebe

    2009-01-01

    Purpose: The aim of this study was to evaluate the induction and rejoining of DNA double strand breaks (DSBs) in melanoma cells exposed to low and high linear energy transfer (LET) radiation. Methods and Materials: DSBs and survival were determined as a function of dose in melanoma cells (B16-F0) irradiated with monoenergetic proton and lithium beams and with a gamma source. Survival curves were obtained by clonogenic assay and fitted to the linear-quadratic model. DSBs were evaluated by the detection of phosphorylated histone H2AX (γH2AX) foci at 30 min and 6 h post-irradiation. Results: Survival curves showed the increasing effectiveness of radiation as a function of LET. γH2AX labeling showed an increase in the number of foci vs. dose for all the radiations evaluated. A decrease in the number of foci was found at 6 h post-irradiation for low LET radiation, revealing the repair capacity of DSBs. An increase in the size of γH2AX foci in cells irradiated with lithium beams was found, as compared with gamma and proton irradiations, which could be attributed to the clusters of DSBs induced by high LET radiation. Foci size increased at 6 h post-irradiation for lithium and proton irradiations in relation with persistent DSBs, showing a correlation with surviving fraction. Conclusions: Our results showed the response of B16-F0 cells to charged particle beams evaluated by the detection of γH2AX foci. We conclude that γH2AX foci size is an accurate parameter to correlate the rejoining of DSBs induced by different LET radiations and radiosensitivity.

  7. DNA double strand break repair is enhanced by P53 following induction by DNA damage and is dependent on the C-terminal domain of P53

    International Nuclear Information System (INIS)

    Wei Tang; Powell, Simon N.

    1996-01-01

    Purpose: The tumor suppressor gene p53 can mediate cell cycle arrest or apoptosis in response to DNA damage. Accumulating evidence suggests that it may also directly or indirectly influence the DNA repair machinery. In the present study, we investigated whether p53, induced by DNA damage, could enhance the rejoining of double-strand DNA breaks. Materials and Methods: DNA double-strand breaks (dsb) were made by restriction enzyme digestion of a plasmid, between a promoter and a 'reporter' gene: luciferase (LUC) or chloramphenicol acetyl-transferase (CAT). Linear or circular plasmid DNA (LUC or CAT) was co-transfected with circular β-Gal plasmid (to normalize for uptake) into mouse embryonic fibroblasts genetically matched to be (+/+) or (-/-) for p53. Their ability to rejoin linearized plasmid was measured by the luciferase or CAT activity detected in rescued plasmids. The activity detected in cells transfected with linear plasmid was scored relative to the activity detected in cells transfected with circular plasmid. Results: Ionizing radiation (IR, 2 Gy) enhanced the dsb repair activity in wild type p53 cells; however, p53 null cells lose this effect, indicating that the enhancement of dsb repair was p53-dependent. REF cells with dominant-negative mutant p53 showed a similar induction compared with the parental REF cells with wild-type p53. This ala-143 mutant p53 prevents cell cycle arrest and transactivation of p21 WAF1/cip1) following IR, indicating that the p53-dependent enhancement of DNA repair is distinct from transactivation. Immortalized murine embryonic fibroblasts, 10(1)VasK1 cells, which express p53 cDNA encoding a temperature-sensitive mutant in the DNA sequence specific binding domain (ala135 to val135) with an alternatively spliced C-terminal domain (ASp53: amino-acids 360-381) and, 10(1)Val5 cells, which express the normal spliced p53 (NSp53) with the same temperature-sensitive mutant were compared. It was found that 10(1)VasK1 cells showed no DNA

  8. Rapid dating of recent sediments in Loch Ness. Inductively coupled plasma mass spectrometric measurements of global fallout plutonium

    International Nuclear Information System (INIS)

    Ketterer, Michael E.; Hafer, Kevin M.; Jones, Vivienne J.; Appleby, Peter G.

    2004-01-01

    The 239+240 Pu activity profile is determined for a sediment core collected from 170-m depth at Loch Ness, Scotland. These measurements use magnetic sector inductively coupled plasma mass spectrometry for rapid determination of Pu activities and 240 Pu/ 239 Pu atom ratios. A 239+240 Pu detection limit of 0.1 Bq/kg is obtained for 2 g of acid-leached sediment; 242 Pu is used as a spike isotope. The Pu activity profile exhibits a maximum of 42.7±0.3 Bq/kg 239+240 Pu in the 9-10-cm depth interval. The position of this maximum coincides with peaks in the 241 Am and 137 Cs activity profiles. These peak activities are ascribed to the 1963/1964 peak fallout from atmospheric testing of nuclear weapons. The 240 Pu/ 239 Pu atom ratios are in the range 0.15-0.20, in agreement with the expected range of 0.166-0.194 for Northern Hemisphere fallout, and do not suggest the presence of other contributing sources. This study demonstrates that ICPMS has considerable potential for rapid determination of the chronology of post-1950 sediments, and also for validating 210 Pb dates where chronologies over longer time-scales are needed

  9. Rapid dating of recent sediments in Loch Ness. Inductively coupled plasma mass spectrometric measurements of global fallout plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Ketterer, Michael E.; Hafer, Kevin M. [Department of Chemistry, Northern Arizona University, Flagstaff, AZ 86011-5698 (United States); Jones, Vivienne J. [Environmental Change Research Centre, University College London, 26 Bedford Way, London WC1H 0AP (United Kingdom); Appleby, Peter G. [Department of Mathematical Sciences, University of Liverpool, P.O. Box 147, Liverpool L69 3BX (United Kingdom)

    2004-04-25

    The {sup 239+240}Pu activity profile is determined for a sediment core collected from 170-m depth at Loch Ness, Scotland. These measurements use magnetic sector inductively coupled plasma mass spectrometry for rapid determination of Pu activities and {sup 240}Pu/{sup 239}Pu atom ratios. A {sup 239+240}Pu detection limit of 0.1 Bq/kg is obtained for 2 g of acid-leached sediment; {sup 242}Pu is used as a spike isotope. The Pu activity profile exhibits a maximum of 42.7{+-}0.3 Bq/kg {sup 239+240}Pu in the 9-10-cm depth interval. The position of this maximum coincides with peaks in the {sup 241}Am and {sup 137}Cs activity profiles. These peak activities are ascribed to the 1963/1964 peak fallout from atmospheric testing of nuclear weapons. The {sup 240}Pu/{sup 239}Pu atom ratios are in the range 0.15-0.20, in agreement with the expected range of 0.166-0.194 for Northern Hemisphere fallout, and do not suggest the presence of other contributing sources. This study demonstrates that ICPMS has considerable potential for rapid determination of the chronology of post-1950 sediments, and also for validating {sup 210}Pb dates where chronologies over longer time-scales are needed.

  10. Induction of double-strand breaks in DNA of prokaryotes and eukaryotes and their repair. 1. Application of elastoviscosimetry for studying double-strand breaks in DNA of Escherichia coli induced by. gamma. -irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Bresler, S E; Noskin, L A; Suslov, A V [AN SSSR, Leningrad. Inst. Yadernoj Fiziki

    1980-11-01

    It is shown that the method of elastoviscosimetry gives a possibility to record the formation of DNA double-strand breaks in Escherichia coli cells induced by ..gamma.. irradiation at doses close to D/sub 37/. The dependence of changes of elastoviscosity parameter on the dose (tau/sub 0/) passes through the maximum. It is shown that the ascending section of this curve (at minimum ..gamma.. irradiation doses) characterizes the relaxation process of the superspiralised chromosome in nucleotide of the E. coli. This relaxation is observed due to ..gamma.. induced damages which are not double-strand breaks. By the maximum position one can judge on a dose yield of the first DNA double-strand break, the descending part of the dose curve describes the kinetics of accumulation of breaks with the dose increase. The analysis of the data obtained gives the possibility to come to the conclusion that when applying a usual technique of irradiation and lysis of cells not providing for special measures on inhibition of endo-and exonuclease activity in ..gamma.. irradiated cells, the dose yield of double-strand breaks noticeably increases (by 4.2 times). In the case of an essential, though incomplete, inhibition of nuclease activities in ..gamma.. irradiated cells the dose yield of breaks approximately corresponds to the dose curve of inactivation of these cells (D/sub 37/12.5+-3.0 krad, the first double-strand break -at 14.5+-2.4 krad).

  11. Induction of double-strand breaks in DNA of prokaryotes and eukaryotes and their repair. 1. Application of elastoviscosimetry for studying double-strand breaks in DNA of Escherichia coli induced by γ-irradiation

    International Nuclear Information System (INIS)

    Bresler, S.E.; Noskin, L.A.; Suslov, A.V.

    1980-01-01

    It is shown that the method of elastoviscosimetry gives a possibility to record the formation of DNA double-strand breaks in Escherichia coli cells induced by γ irradiation at doses close to D 37 . The dependence of changes of elastoviscosity parameter on the dose (tau 0 ) passes through the maximum. It is shown that the ascending section of this curve (at minimum γ irradiation doses) characterizes the relaxation process of the superspiralised chromosome in nucleotide of the E. coli. This relaxation is observed due to γ induced damages which are not double-strand breaks. By the maximum position one can judge on a dose yield of the first DNA double-strand break, the descending part of the dose curve describes the kinetics of accumulation of breaks with the dose increase. The analysis of the data obtained gives the possibility to come to the conclusion that when applying a usual technique of irradiation and lysis of cells not providing for special measures on inhibition of endo-and exonuclease activity in γ irradiated cells, the dose yield of double-strand breaks noticeably increases (by 4.2 times). In the case of an essential, though incomplete, inhibition of nuclease activities in γ irradiated cells the dose yield of breaks approximately corresponds to the dose curve of inactivation of these cells (D 37 12.5+-3.0 krad, the first double-strand break -at 14.5+-2.4 krad)

  12. Induction and repair of DNA double-strand breaks in blood lymphocytes of patients undergoing {sup 18}F-FDG PET/CT examinations

    Energy Technology Data Exchange (ETDEWEB)

    May, Matthias S. [University Hospital Erlangen, Department of Radiology, Erlangen (Germany); Brand, Michael; Wuest, Wolfgang; Anders, Katharina; Uder, Michael; Kuefner, Michael A. [University Hospital Erlangen, Department of Radiology, Erlangen (Germany); Kuwert, Torsten; Prante, Olaf; Schmidt, Daniela; Maschauer, Simone [University Hospital Erlangen, Department of Nuclear Medicine, Erlangen (Germany); Semelka, Richard C. [University of North Carolina, Department of Radiology, Chapel Hill, NC (United States)

    2012-11-15

    The purpose of this study was to evaluate DNA double-strand breaks (DSBs) in blood lymphocytes of patients undergoing positron emission tomography (PET)/CT using {gamma}-H2AX immunofluorescence microscopy and to differentiate between {sup 18}F-fluorodeoxyglucose (FDG) and CT-induced DNA lesions. This study was approved by the local Ethics Committee and complies with Health Insurance Portability and Accountability Act (HIPAA) requirements. After written informed consent was obtained, 33 patients underwent whole-body {sup 18}F-FDG PET/CT (3 MBq/kg body weight, 170/100 reference mAs at 120 kV). The FDG PET and CT portions were performed as an initial CT immediately followed by the PET. Blood samples were obtained before, at various time points following {sup 18}F-FDG application and up to 24 h after the CT scan. Distinct foci representing DSBs were quantified in isolated lymphocytes using fluorescence microscopy after staining against the phosphorylated histone variant {gamma}-H2AX. The DSB values at the various time points were significantly different (p < 0.001). The median baseline level was 0.08/cell (range 0.06-0.12/cell). Peaks of radiation-induced DSBs were found 30 min after {sup 18}F-FDG administration (median excess foci 0.11/cell, range 0.06-0.27/cell) and 5 min after CT (median excess foci 0.17/cell, range 0.05-0.54/cell). A significant correlation between CT-induced DSBs and dose length product was obtained ({rho} = 0.898, p < 0.001). After 24 h DSB values were still slightly but significantly elevated (median foci 0.11/cell, range 0.10-0.14/cell, p = 0.003) compared to pre-exposure levels. PET/CT-induced DSBs can be monitored using {gamma}-H2AX immunofluorescence microscopy. Peak values may be obtained 30 min after {sup 18}F-FDG injection and 5 min after CT. The radionuclide contributes considerably to the total DSB induction in this setting. (orig.)

  13. Application of analytical capability to predict rapid cladding cooling and quench during the blowdown phase of a large break loss-of-coolant accident

    International Nuclear Information System (INIS)

    Aksan, S.N.; Tolman, E.L.; Nelson, R.A.

    1983-01-01

    Large-break Experiments L2-2 and L2-3 conducted in the Loss-of-Fluid Test (LOFT) facility experienced core-wide rapid quenches early in the blowdown transients. To further investigate rapid cladding quenches, separate effects experiments using Semiscale solid-type electric heater rods were conducted in the LOFT Test Support Facility (LTSF) over a wide range of inlet coolant conditions. The analytical capability to predict the cladding temperature response from selected LTSF experiments estimated to bound the hydraulic conditions causing the LOFT early blowdown quenches was investigated using the RELAP4 computer code and was shown to be acceptable over the film boiling cooldown phase. This analytical capability was then used to investigate the behavior of nuclear fuel rods under the same hydraulic conditions. The calculations show that, under rapid cooling conditions, the behaviors of nuclear and electrical heater rods are significantly different because the nuclear rods are conduction limited, while the electrical rods are convection limited

  14. Induction of rapid and selective cell necrosis in Drosophila using Bacillus thuringiensis Cry toxin and its silkworm receptor.

    Science.gov (United States)

    Obata, Fumiaki; Tanaka, Shiho; Kashio, Soshiro; Tsujimura, Hidenobu; Sato, Ryoichi; Miura, Masayuki

    2015-07-08

    Genetic ablation of target cells is a powerful tool to study the origins and functions of cells, tissue regeneration, or pathophysiology in a human disease model in vivo. Several methods for selective cell ablation by inducing apoptosis have been established, using exogenous toxins or endogenous proapoptotic genes. However, their application is limited to cells with intact apoptotic machinery. Herein, we established a method for inducing rapid and selective cell necrosis by the pore-forming bacterial toxin Cry1Aa, which is specifically active in cells expressing the Cry1Aa receptor (CryR) derived from the silkworm Bombyx mori. We demonstrated that overexpressing CryR in Drosophila melanogaster tissues induced rapid cell death of CryR-expressing cells only, in the presence of Cry1Aa toxin. Cry/CryR system was effective against both proliferating cells in imaginal discs and polyploid postmitotic cells in the fat body. Live imaging analysis of cell ablation revealed swelling and subsequent osmotic lysis of CryR-positive cells after 30 min of incubation with Cry1Aa toxin. Osmotic cell lysis was still triggered when apoptosis, JNK activation, or autophagy was inhibited, suggesting that Cry1Aa-induced necrotic cell death occurred independently of these cellular signaling pathways. Injection of Cry1Aa into the body cavity resulted in specific ablation of CryR-expressing cells, indicating the usefulness of this method for in vivo cell ablation. With Cry toxins from Bacillus thuringiensis, we developed a novel method for genetic induction of cell necrosis. Our system provides a "proteinous drill" for killing target cells through physical injury of the cell membrane, which can potentially be used to ablate any cell type in any organisms, even those that are resistant to apoptosis or JNK-dependent programmed cell death.

  15. A study of Ni-based WC composite coatings by laser induction hybrid rapid cladding with elliptical spot

    International Nuclear Information System (INIS)

    Zhou Shengfeng; Huang Yongjun; Zeng Xiaoyan

    2008-01-01

    Ni-based WC composite coatings by laser induction hybrid rapid cladding (LIHRC) with elliptical spot were investigated. Results indicate that the efficiency using the elliptical spot of 6 mm x 4 mm (the major and minor axis of laser beam are 6 mm and 4 mm, respectively, the major axis is parallel to the direction of laser scanning) is higher than that using the elliptical spot of 4 mm x 6 mm (the major axis is perpendicular to the direction of laser scanning). The precipitated carbides with the blocky and bar-like shape indicate that WC particles suffer from the heat damage of 'the disintegration pattern + the growth pattern', whichever elliptical spot is used at low laser scanning speed. However, at high laser scanning speed, the blocky carbides are only formed if the elliptical spot of 6 mm x 4 mm is adopted, showing that WC particles present the heat damage of 'the disintegration pattern', whereas the fine carbides are precipitated when the elliptical spot of 4 mm x 6 mm is used, showing that WC particles take on the heat damage of 'the radiation pattern'. Especially, the efficiency of LIHRC is increased much four times higher than that of the general laser cladding and crack-free ceramic-metal coatings can be obtained

  16. Qu'Appelle River Dam, dam break analysis using advanced GIS tools for rapid modelling and inundation mapping

    Energy Technology Data Exchange (ETDEWEB)

    Bonin, D. [Hatch Energy, Winnipeg, MB (Canada); Campbell, C. [Saskatchewan Watershed Authority, Moose Jaw, SK (Canada); Groeneveld, J. [Hatch Energy, Calgary, AB (Canada)

    2008-07-01

    The South Saskatchewan River Project (SSRP) comprises a multi-purpose reservoir that provides water for conservation and irrigation, flood control, power generation, recreation, and municipal and industrial water supply. In addition to the 64 m high Gardiner Dam, the 27 m high Qu'Appelle River Dam and the 22 km long Lake Diefenbaker Reservoir, the SSRP also includes ancillary works. The Qu'Appelle River valley extends for 458 km before connecting to the Assiniboine River. The valley is incised up to 90 m in depth and is a popular cottaging and recreational area with several major communities located in the flood plain. In the event of a breach of the Qu'Appelle Dam, the discharge will increase from a normal maximum discharge of under 60 m{sup 3} per second to over 50,000 m{sup 3} per second. The Saskatchewan Watershed Authority (SWA) is responsible for ensuring safe development of the Province's water resources, without affecting reservoir or lake operations, and preventing damage from flooding, erosion or land slides. It is in the process of developing Hazard Assessments and emergency preparedness plans for each of their dams in accordance with the Canadian Dam Safety Guidelines. Studies using GIS technology and the hydrodynamic routing model HEC-RAS have been completed to evaluate the potential inundation that may result in the event of failure of the Qu'Appelle River Dam. These studies involved the development of a breach parameter model using a breach data set revised to better reflect the Qu'Appelle River Dam; the development of a dam break model for the Qu'Appelle River Dam and downstream river and flood plain; and, the use of this model to simulate two potential dam failure scenarios for the Qu'Appelle River Dam, notably failure during passage of the PMF and failure during fair weather conditions. Inundation maps have been prepared for the downstream Qu'Appelle River valley for each of the above events. 3 refs., 4

  17. Rapid Recruitment of BRCA1 to DNA Double-Strand Breaks Is Dependent on Its Association with Ku80▿ †

    Science.gov (United States)

    Wei, Leizhen; Lan, Li; Hong, Zehui; Yasui, Akira; Ishioka, Chikashi; Chiba, Natsuko

    2008-01-01

    BRCA1 is the first susceptibility gene to be linked to breast and ovarian cancers. Although mounting evidence has indicated that BRCA1 participates in DNA double-strand break (DSB) repair pathways, its precise mechanism is still unclear. Here, we analyzed the in situ response of BRCA1 at DSBs produced by laser microirradiation. The amino (N)- and carboxyl (C)-terminal fragments of BRCA1 accumulated independently at DSBs with distinct kinetics. The N-terminal BRCA1 fragment accumulated immediately after laser irradiation at DSBs and dissociated rapidly. In contrast, the C-terminal fragment of BRCA1 accumulated more slowly at DSBs but remained at the sites. Interestingly, rapid accumulation of the BRCA1 N terminus, but not the C terminus, at DSBs depended on Ku80, which functions in the nonhomologous end-joining (NHEJ) pathway, independently of BARD1, which binds to the N terminus of BRCA1. Two small regions in the N terminus of BRCA1 independently accumulated at DSBs and interacted with Ku80. Missense mutations found within the N terminus of BRCA1 in cancers significantly changed the kinetics of its accumulation at DSBs. A P142H mutant failed to associate with Ku80 and restore resistance to irradiation in BRCA1-deficient cells. These might provide a molecular basis of the involvement of BRCA1 in the NHEJ pathway of the DSB repair process. PMID:18936166

  18. Rocuronium Versus Suxamethonium: A Survey of First-line Muscle Relaxant Use in UK Prehospital Rapid Sequence Induction.

    Science.gov (United States)

    Hartley, Emma L; Alcock, Roger

    2015-04-01

    Prehospital anaesthesia in the United Kingdom (UK) is provided by Helicopter Emergency Medical Service (HEMS) and British Association for Immediate Care (BASICS), a road-based service. Muscle relaxation in rapid sequence induction (RSI) has been traditionally undertaken with the use of suxamethonium; however, rocuronium at higher doses has comparable intubating conditions with fewer side effects. The aim of this survey was to establish how many prehospital services in the UK are now using rocuronium as first line in RSI. An online survey was constructed identifying choice of first-line muscle relaxant for RSI and emailed to lead clinicians for BASICS and HEMS services across the UK. If rocuronium was used, further questions regarding optimal dose, sugammadex, contraindications, and difference in intubating conditions were asked. A total of 29 full responses (93.5%) were obtained from 31 services contacted. Suxamethonium was used first line by 17 prehospital services (58.6%) and rocuronium by 12 (41.4%). In 11 services (91.7%), a dose of 1 mg/kg of rocuronium was used, and in one service, 1.2 mg/kg (8.3%) was used. No services using rocuronium carried sugammadex. In five services, slower relaxation time was found using rocuronium (41.7%), and in seven services, no difference in intubation conditions were noted (58.3%). Contraindications to rocuronium use included high probability of difficult airway and anaphylaxis. Use of rocuronium as first-line muscle relaxant in prehospital RSI is increasing. Continued auditing of practice will ascertain which services have adopted change and identify if complications of failed intubation increase as a result.

  19. Rapid Induction of Multiple Terpenoid Groups by Ponderosa Pine in Response to Bark Beetle-Associated Fungi.

    Science.gov (United States)

    Keefover-Ring, Ken; Trowbridge, Amy; Mason, Charles J; Raffa, Kenneth F

    2016-01-01

    Ponderosa pine (Pinus ponderosa) is a major and widely distributed component of conifer biomes in western North America and provides substantial ecological and economic benefits. This tree is exposed to several tree-killing bark beetle-microbial complexes, including the mountain pine beetle (Dendroctonus ponderosae) and the phytopathogenic fungus Grosmannia clavigera that it vectors, which are among the most important. Induced responses play a crucial role in conifer defenses, yet these have not been reported in ponderosa pine. We compared concentrations of terpenes and a phenylpropanoid, two phytochemical classes with strong effects against bark beetles and their symbionts, in constitutive phloem tissue and in tissue following mechanical wounding or simulated D. ponderosae attack (mechanical wounding plus inoculation with G. clavigera). We also tested whether potential induced responses were localized or systemic. Ponderosa pines showed pronounced induced defenses to inoculation, increasing their total phloem concentrations of monoterpenes 22.3-fold, sesquiterpenes 56.7-fold, and diterpenes 34.8-fold within 17 days. In contrast, responses to mechanical wounding alone were only 5.2, 11.3, and 7.7-fold, respectively. Likewise, the phenylpropanoid estragole (4-allyanisole) rose to 19.1-fold constitutive levels after simulated attack but only 4.4-fold after mechanical wounding. Overall, we found no evidence of systemic induction after 17 days, which spans most of this herbivore's narrow peak attack period, as significant quantitative and compositional changes within and between terpenoid groups were localized to the wound site. Implications to the less frequent exploitation of ponderosa than lodgepole pine by D. ponderosae, and potential advantages of rapid localized over long-term systemic responses in this system, are discussed.

  20. Differential repair of radiation-induced DNA damage in cells of human squamous cell carcinoma and the effect of caffeine and cysteamine on induction and repair of DNA double-strand breaks

    Energy Technology Data Exchange (ETDEWEB)

    Smeets, M.F.M.A.; Mooren, E.H.M.; Abdel-Wahab, A.H.A.; Begg, A.C. [Netherlands Cancer Institute, Amsterdam (Netherlands)

    1994-11-01

    The goal of these experiments was to investigate further the relationship between DNA double-strand breaks and cell killing in human tumor cells, first by comparing different cell lines, and second by radiomodification studies. Field-inversion gel electrophoresis was used to quantify double-strand breaks. Two subclones of the radioresistant human squamous cell carcinoma line SQ20B (SQD9 and SQG6) were compared. These subclones differed in DNA index by a factor of 1.7 but showed the same resistance to radiation as cells of the parental cell line. It was found that, although induction of DSBs was not significantly different in the two cell lines, the t{sub 1/2} of the fast component of repair was significantly shorter for SQD9 cells, leading to greater overall repair which was not reflected in increased survival. Caffeine and cysteamine were tested as modifiers of radiosensitivity, using the radioresistant SQ20B line and the radiosensitive SCC61 cell line. No effect of caffeine was seen when the drug was present only during irradiation. Postirradiation incubations with caffeine, however, resulted in a dose reduction factor greater than 2.0 in cell survival for both cell lines. In contrast, induction of DSBs was reduced by caffeine, and no effect on DSB repair was observed. Cysteamine led to a dose protection factor greater than 1.8 in cell survival in both cell lines. A reduction in induced DSBs was found at high doses corresponding approximately with the increase in cell survival. Over the same (low) dose range, however, the correlation between DSB induction and cell killing was poor. These data indicate that DSB induction does not correlate well with cell killing either for different cell lines, for radiochemical modification (cysteamine) or for some other types of modification (caffeine). 31 refs., 8 figs.

  1. Induction and rejoining of DNA double-strand breaks and interphase chromosome breaks after exposure to x-rays in one normal and two hypersensitive human fibroblast cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Badie, C.; Alsbeih, G.; Malaise, E.P. [Institute Gustave-Roussy, Villejuif (France)] [and others

    1995-10-01

    The aim of this work was to measure simultaneously and in a quantitative manner double-strand breaks (DSBs), interphase chromosome breaks and cell lethality either immediately after irradiation, or at various times thereafter (up to 24 h), in cells of three nontransformed human fibroblast cell lines of widely different intrinsic radiosensitivity. We wished to assess initial damage, repair kinetics and residual damage at the DNA and the chromosome level, and to correlate these parameters with cell killings. We employed HF19 cells, a normal fibroblast cell line, AT2 cells, a radiosensitive cell line from a patient suffering from ataxia telangiectasia (AT), and 180BR cells, a radiosensitive cell line from a patient with no clinical symptoms of AT. AT2 and 180BR cells, in addition to being radiosensitive, also display a reduced ability to repair potentially lethal damage compared to HF19 cells. The yield of DSBs, as measured by pulsed-field gel electrophoresis, is similar in all three cell lines (slopes correspond to 1.6-1.7% Gy{sup -1} of DNA-associated radioactivity released from the gel well into the lane). In contrast, residual DSBs measured 24 h after irradiation are almost zero for HF19 cells (0.1% confidence interval=0-1.4%), but are 12.5% ({plus_minus}2.3%) and 43.8% ({plus_minus}1.2%) of those measured immediately after irradiation in HF19, AT2 and 180BR cells, respectively. Neither the initial yield of DSBs nor that of excess interphase chromosomes breaks can explain the differences in radiosensitivity between the three cell lines; however, there is a correlation between residual DSBs, rate of DSB rejoining at 24 h, residual interphase chromosome breaks on the one hand and cell survival on the other hand. 74 refs., 6 figs., 4 tabs.

  2. High-dose rapid and standard induction chemotherapy for patients aged over 1 year with stage 4 neuroblastoma: a randomised trial.

    Science.gov (United States)

    Pearson, Andrew D J; Pinkerton, C Ross; Lewis, Ian J; Imeson, John; Ellershaw, Caroline; Machin, David

    2008-03-01

    The current standard treatment for patients with high-risk neuroblastoma includes initial induction chemotherapy with a 21-day interval between induction treatments. We aimed to assess whether an intensive chemotherapy protocol that had a 10-day interval between treatments would improve event-free survival (EFS) in patients aged 1 year or over with high-risk neuroblastoma. Between Oct 30, 1990, and March 18, 1999, patients with stage 4 neuroblastoma who had not received previous chemotherapy were enrolled from 29 centres in Europe. Patients were randomly assigned to rapid treatment (cisplatin [C], vincristine [O], carboplatin [J], etoposide [E], and cyclophosphamide [C], known as COJEC) or standard treatment (vincristine [O], cisplatin [P], etoposide [E], and cyclophosphamide [C], ie, OPEC, alternated with vincristine [O], carboplatin [J], etoposide [E], and cyclophosphamide [C], ie, OJEC). Both regimens used the same total cumulative doses of each drug (except vincristine), but the dose intensity of the rapid regimen was 1.8-times higher than that of the standard regimen. The standard regimen was given every 21 days if patients showed haematological recovery, whereas the rapid regimen was given every 10 days irrespective of haematological recovery. Response to chemotherapy was assessed according to the conventional International Neuroblastoma Response Criteria (INRC). In responders, surgical excision of the primary tumour was attempted, followed by myeloablation (with 200 mg/m2 of melphalan) and haemopoietic stem-cell rescue. Primary endpoints were 3-year, 5-year, and 10-year EFS. Data were analysed by intention to treat. This trial is registered on the clinical trials site of the US National Cancer Institute website, number NCT00365755, and also as EU-20592 and CCLG-NB-1990-11. 262 patients, of median age 2.95 years (range 1.03-20.97), were randomly assigned-132 patients to standard and 130 patients to rapid treatment. 111 patients in the standard group and 109

  3. Comparison of single-use and reusable metal laryngoscope blades for orotracheal intubation during rapid sequence induction of anesthesia: a multicenter cluster randomized study.

    Science.gov (United States)

    Amour, Julien; Le Manach, Yannick Le; Borel, Marie; Lenfant, François; Nicolas-Robin, Armelle; Carillion, Aude; Ripart, Jacques; Riou, Bruno; Langeron, Olivier

    2010-02-01

    Single-use metal laryngoscope blades are cheaper and carry a lower risk of infection than reusable metal blades. The authors compared single-use and reusable metal blades during rapid sequence induction of anesthesia in a multicenter cluster randomized trial. One thousand seventy-two adult patients undergoing general anesthesia under emergency conditions and requiring rapid sequence induction were randomly assigned on a weekly basis to either single-use or reusable metal blades (cluster randomization). After induction, a 60-s period was allowed to complete intubation. In the case of failed intubation, a second attempt was performed using the opposite type of blade. The primary endpoint was the rate of failed intubation, and the secondary endpoints were the incidence of complications (oxygen desaturation, lung aspiration, and/or oropharynx trauma) and the Cormack and Lehane score. Both groups were similar in their main characteristics, including the risk factors for difficult intubation. The rate of failed intubation was significantly decreased with single-use metal blades at the first attempt compared with reusable blades (2.8 vs. 5.4%, P < 0.05). In addition, the proportion of grades III and IV in Cormack and Lehane score were also significantly decreased with single-use metal blades (6 vs. 10%, P < 0.05). The global complication rate did not reach statistical significance, although the same trend was noted (6.8% vs. 11.5%, P = not significant). An investigator survey and a measure of illumination pointed that illumination might have been responsible for this result. The single-use metal blade was more efficient than a reusable metal blade in rapid sequence induction of anesthesia.

  4. Heterochromatinization associated with cell differentiation as a model to study DNA double strand break induction and repair in the context of higher-order chromatin structure

    Czech Academy of Sciences Publication Activity Database

    Falk, Martin; Lukášová, Emilie; Štefančíková, Lenka; Baranová, E.; Falková, Iva; Ježková, L.; Davídková, Marie; Bačíková, Alena; Vachelová, Jana; Michaelidesová, Anna; Kozubek, Stanislav

    2014-01-01

    Roč. 83, Jan (2014), s. 177-185 ISSN 0969-8043 R&D Projects: GA MŠk(CZ) LD12039 Institutional support: RVO:68081707 ; RVO:61389005 Keywords : DNA double strand break (DSB) repair * Immature and terminally differentiated granulocytes * gamma H2AX/53BP1 repair foci Subject RIV: BO - Biophysics; BO - Biophysics (UJF-V) Impact factor: 1.231, year: 2014

  5. Induction and repair of DNA double-strand breaks in hippocampal neurons of mice of different age after exposure to 60Co γ-rays in vivo and in vitro

    Science.gov (United States)

    Kozhina, R. A.; Chausov, V. N.; Kuzmina, E. A.; Boreyko, A. V.

    2018-04-01

    One of the central problems of modern radiobiology is the study of DNA damage induction and repair mechanisms in central nervous system cells, in particular, in hippocampal cells. The study of the regularities of molecular damage formation and repair in the hippocampus cells is of special interest, because these cells, unlike most cells of the central nervous system (CNS), keep proliferative activity, i.e. ability to neurogenesis. Age-related changes in hippocampus play an important role, which could lead to radiosensitivity changes in neurons to the ionizing radiation exposure. Regularities in DNA double-strand breaks (DSB) induction and repair in different aged mice hippocampal cells in vivo and in vitro under the action of γ-rays 60Co were studied with DNA comet-assay. The obtained dose dependences of DNA DSB induction are linear both in vivo and in vitro. It is established that in young animals' cells, the degree of DNA damage is higher than in older animals. It is shown that repair kinetics is basically different for exposure in vivo and in vitro.

  6. Breaking Bat

    Science.gov (United States)

    Aguilar, Isaac-Cesar; Kagan, David

    2013-01-01

    The sight of a broken bat in Major League Baseball can produce anything from a humorous dribbler in the infield to a frightening pointed projectile headed for the stands. Bats usually break at the weakest point, typically in the handle. Breaking happens because the wood gets bent beyond the breaking point due to the wave sent down the bat created…

  7. TU-EF-304-10: Efficient Multiscale Simulation of the Proton Relative Biological Effectiveness (RBE) for DNA Double Strand Break (DSB) Induction and Bio-Effective Dose in the FLUKA Monte Carlo Radiation Transport Code

    Energy Technology Data Exchange (ETDEWEB)

    Moskvin, V; Tsiamas, P; Axente, M; Farr, J [St. Jude Children’s Research Hospital, Memphis, TN (United States); Stewart, R [University of Washington, Seattle, WA. (United States)

    2015-06-15

    Purpose: One of the more critical initiating events for reproductive cell death is the creation of a DNA double strand break (DSB). In this study, we present a computationally efficient way to determine spatial variations in the relative biological effectiveness (RBE) of proton therapy beams within the FLUKA Monte Carlo (MC) code. Methods: We used the independently tested Monte Carlo Damage Simulation (MCDS) developed by Stewart and colleagues (Radiat. Res. 176, 587–602 2011) to estimate the RBE for DSB induction of monoenergetic protons, tritium, deuterium, hellium-3, hellium-4 ions and delta-electrons. The dose-weighted (RBE) coefficients were incorporated into FLUKA to determine the equivalent {sup 6}°60Co γ-ray dose for representative proton beams incident on cells in an aerobic and anoxic environment. Results: We found that the proton beam RBE for DSB induction at the tip of the Bragg peak, including primary and secondary particles, is close to 1.2. Furthermore, the RBE increases laterally to the beam axis at the area of Bragg peak. At the distal edge, the RBE is in the range from 1.3–1.4 for cells irradiated under aerobic conditions and may be as large as 1.5–1.8 for cells irradiated under anoxic conditions. Across the plateau region, the recorded RBE for DSB induction is 1.02 for aerobic cells and 1.05 for cells irradiated under anoxic conditions. The contribution to total effective dose from secondary heavy ions decreases with depth and is higher at shallow depths (e.g., at the surface of the skin). Conclusion: Multiscale simulation of the RBE for DSB induction provides useful insights into spatial variations in proton RBE within pristine Bragg peaks. This methodology is potentially useful for the biological optimization of proton therapy for the treatment of cancer. The study highlights the need to incorporate spatial variations in proton RBE into proton therapy treatment plans.

  8. Comparison of the induction and disappearance of DNA double strand breaks and gamma-H2AX foci after irradiation of chromosomes in G1-phase or in condensed metaphase cells.

    Science.gov (United States)

    Kato, Takamitsu A; Okayasu, Ryuichi; Bedford, Joel S

    2008-03-01

    The induction and disappearance of DNA double strand breaks (DSBs) after irradiation of G1 and mitotic cells were compared with the gamma-H2AX foci assay and a gel electrophoresis assay. This is to determine whether cell cycle related changes in chromatin structure might influence the gamma-H2AX assay which depends on extensive phosphorylation and dephosphorylation of the H2AX histone variant surrounding DSBs. The disappearance of gamma-H2AX foci after irradiation was much slower for mitotic than for G1 cells. On the other hand, no difference was seen for the gel electrophoresis assay. Our data may suggest the limited accessibility of dephosphorylation enzyme in irradiated metaphase cells or trapped gamma-H2AX in condensed chromatin.

  9. Comparison of the induction and disappearance of DNA double strand breaks and γ-H2AX foci after irradiation of chromosomes in G1-phase or in condensed metaphase cells

    International Nuclear Information System (INIS)

    Kato, Takamitsu A.; Okayasu, Ryuichi; Bedford, Joel S.

    2008-01-01

    The induction and disappearance of DNA double strand breaks (DSBs) after irradiation of G1 and mitotic cells were compared with the γ-H2AX foci assay and a gel electrophoresis assay. This is to determine whether cell cycle related changes in chromatin structure might influence the γ-H2AX assay which depends on extensive phosphorylation and dephosphorylation of the H2AX histone variant surrounding DSBs. The disappearance of γ-H2AX foci after irradiation was much slower for mitotic than for G1 cells. On the other hand, no difference was seen for the gel electrophoresis assay. Our data may suggest the limited accessibility of dephosphorylation enzyme in irradiated metaphase cells or trapped γ-H2AX in condensed chromatin

  10. Redundancy and molecular evolution: the rapid Induction of bone formation by the mammalian transforming growth factor-β3 isoform

    Directory of Open Access Journals (Sweden)

    Ugo Ripamonti

    2016-09-01

    Full Text Available The soluble osteogenic molecular signals of the transforming growth factor-β (TGF-β supergene family are the molecular bases of the induction of bone formation and postnatal bone tissue morphogenesis with translation into clinical contexts. The mammalian TGF-β3 isoform, a pleiotropic member of the family, controls a vast array of biological processes including the induction of bone formation. Recombinant hTGF-β3 induces substantial bone formation when implanted with either collagenous bone matrices or coral-derived macroporous bioreactors in the rectus abdominis muscle of the non-human primate Papio ursinus. In marked contrast, the three mammalian TGF-βs do not initiate the induction of bone formation in rodents and lagomorphs. The induction of bone by hTGF-β3/preloaded bioreactors is orchestrated by inducing fibrin-fibronectin rings that structurally organize tissue patterning and morphogenesis within the macroporous spaces. Induced advancing extracellular matrix rings provide the structural anchorage for hyper chromatic cells, interpreted as differentiating osteoblasts re-programmed by hTGF-β3 from invading myoblastic and/or pericytic differentiated cells. Runx2 and Osteocalcin expression are significantly up-regulated correlating to multiple invading cells differentiating into the osteoblastic phenotype. Bioreactors pre-loaded with recombinant human Noggin (hNoggin, a BMPs antagonist, show down-regulation of BMP-2 and other profiled osteogenic proteins’ genes resulting in minimal bone formation. Coral-derived macroporous constructs preloaded with binary applications of hTGF-β3 and hNoggin also show down-regulation of BMP-2 with the induction of limited bone formation. The induction of bone formation by hTGF-β3 is via the BMPs pathway and it is thus blocked by hNoggin. Our systematic studies in Papio ursinus with translational hTGF-β3 in large cranio-mandibulo-facial defects in humans are now requesting the re-evaluation of Bone

  11. Dose requirements of alfentanil to eliminate autonomic responses during rapid-sequence induction with thiopental 4 mg/kg and rocuronium 0.6 mg/kg.

    Science.gov (United States)

    Abou-Arab, Mohammad H; Rostrup, Morten; Heier, Tom

    2016-12-01

    Opioids are integral part of anesthesia induction, but information on optimal dosing is limited. We aimed to determine doses of alfentanil needed to eliminate increases in 5 autonomic response variables (plasma concentrations of epinephrine, norepinephrine and vasopressin, arterial blood pressure [ABP], and heart rate) during rapid-sequence induction of anesthesia with thiopental 4 mg/kg and rocuronium 0.6 mg/kg. Prospective, randomized, observer-blinded, interventional clinical study. Large academic institution. Eighty-four healthy patients, aged 18 to 55 years, received 1 of 7 assessor-blinded doses of alfentanil (0, 10, 20, 30, 40, 50, and 60 μg/kg) together with thiopental 4 mg/kg and rocuronium 0.6 mg/kg, administered in rapid succession (15 seconds). Laryngoscopy was initiated 40 seconds after rocuronium, and tracheal intubation was concluded within 15 seconds thereafter. An indwelling radial artery catheter was used for hemodynamic monitoring and blood sampling. Relationships between alfentanil dose and response variables were tested with linear regression, and the influence of covariates (sex, body weight, and age) was determined. Alfentanil dose needed to prevent increases in ABP >10% above baseline with 95% probability was estimated with logistic regression. Significant relationships were determined between alfentanil dose and response variables. Clinically interesting influence of covariates was not found. Alfentanil 55 μg/kg was needed to prevent increases in ABP postintubation >10% above baseline with 95% probability. One individual needed a bolus of vasopressor postintubation. Optimal control of autonomic responses during rapid-sequence induction was achieved with clinically relevant doses of alfentanil in healthy patients anesthetized with thiopental 4 mg/kg and rocuronium 0.6 mg/kg. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Bead Injection Extraction Chromatography using High-capacity Lab-on-Valve as a Front End to Inductively Coupled Plasma Mass Spectrometry for Rapid Urine Radiobioassay

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hou, Xiaolin; Roos, Per

    2013-01-01

    A novel bead injection (BI) extraction chromatographic microflow system exploiting high-capacity lab-on-valve (LOV) platform coupled with inductively coupled plasma mass spectrometric detection is developed for rapid and automated determination of plutonium in human urine. A microconduit (1 m......L) incorporated within the LOV processing unit is loaded on-line with a metered amount of disposable extraction chromatographic resin (up to 330 mg of TEVA) through programmable beads transport. Selective capture and purification of plutonium onto the resin beads is then performed by pressure driven flow after...

  13. Re-induction of obese body weight occurs more rapidly and at lower caloric intake in beagles.

    Science.gov (United States)

    Nagaoka, D; Mitsuhashi, Y; Angell, R; Bigley, K E; Bauer, J E

    2010-06-01

    For the purpose of investigating the mechanism of obesity-induction/re-induction including weight-cycling in beagles, a study was conducted using commercially available dog food combined with human food to mimic at home-snacking and diet-supplementation behaviours. Adult female beagles, which had free access to water and exercise, were used (n = 9). All dogs were initially offered two times their daily calculated number of calories using a dry extruded diet plus blend of canola and soybean oils and allowed to eat ad libitum. After 3 weeks, Pecan shortbread cookies were added to the diet mixture. Obesity was induced during a 19-week period with 1875-2250 kcal/day consumed, on average, during this period. The dogs were then subjected to a weight-loss regimen while consuming 490-730 kcal/day. After weight loss, a similar degree of obesity was re-induced for 17 weeks even though dogs consumed only 1125-1250 kcal/day. Body weight, body condition scores, kcal consumption and food efficiency were recorded. Results indicated that less time and fewer kcal were required to re-induce the same degree of obesity compared with the initial obesity induction. Human snack foods appeared to stimulate appetite and thus contribute to the obese state. Food efficiency was also increased during the obesity-reinduction period compared with the induction period. This information may help pet owners better understand the need to limit table scraps and human-type food snacks in dogs prone to obesity as well as weight maintenance after weight loss.

  14. Induction of DNA double-strand breaks by restriction enzymes in X-ray-sensitive mutant Chinese hamster ovary cells measured by pulsed-field gel electrophoresis

    International Nuclear Information System (INIS)

    Kinashi, Yuko; Nagasawa, Hatsumi; Little, J.B.; Okayasu, Ryuichi; Iliakis, G.E.

    1995-01-01

    This investigation was designed to determine whether the cytotoxic effects of different restriction endonucleases are related to the number and type of DNA double-strand breaks (DSBs) they produce. Chinese hamster ovary (CHO) K1 and xrs-5 cells, a radiosensitive mutant of CHO K1, were exposed to restriction endonucleases HaeIII, HinfI, PvuII and BamHI by electroporation. These enzymes represent both blunt and sticky end cutters with differing recognition sequence lengths. The number of DSBs was measured by pulsed-field gel electrophoresis (PFGE). Two forms of PFGE were employed: asymmetric field-inversion gel electrophoresis (AFIGE) for measuring the kinetics of DNA breaks by enzyme digestion and clamped homogeneous gel electrophoresis (CHEF) for examining the size distributions of damaged DNA. The amount of DNA damage induced by exposure to all four restriction enzymes was significantly greater in xrs-5 compared to CHO K1 cells, consistent with the reported DSB repair deficiency in these cells. Since restriction endonucleases produce DSBs alone as opposed to the various types of DNA damage induced by X rays, these results confirm that the repair defect in this mutant involves the rejoining of DSBs. Although the cutting frequency was directly related to the length of the recognition sequence for four restriction enzymes, there was no simple correlation between the cytotoxic effect and the amount of DNA damage produced by each enzyme in either cell line. This finding suggests that the type or nature of the cutting sequence itself may play a role in restriction enzyme-induced cell killing. 32 refs., 6 figs., 3 tabs

  15. A rapid monitoring method for inorganic arsenic in rice flour using reversed phase-high performance liquid chromatography-inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Narukawa, Tomohiro; Chiba, Koichi; Sinaviwat, Savarin; Feldmann, Jörg

    2017-01-06

    A new rapid monitoring method by means of high performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS) following the heat-assisted extraction was developed for measurement of total inorganic arsenic species in rice flour. As(III) and As(V) eluted at the same retention time and completely separated from organoarsenic species by an isocratic elution program on a reversed phase column. Therefore, neither ambiguous oxidation of arsenite to arsenate nor the integration of two peaks were necessary to determine directly the target analyte inorganic arsenic. Rapid injection allowed measuring 3 replicates within 6min and this combined with a quantitative extraction of all arsenic species from rice flour by a 15min HNO 3 -H 2 O 2 extraction makes this the fastest laboratory based method for inorganic arsenic in rice flour. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Rapid induction of dopamine sensitization in the nucleus accumbens shell induced by a single injection of cocaine.

    Science.gov (United States)

    Singer, Bryan F; Bryan, Myranda A; Popov, Pavlo; Robinson, Terry E; Aragona, Brandon J

    2017-05-01

    Repeated intermittent exposure to cocaine results in the neurochemical sensitization of dopamine (DA) transmission within the nucleus accumbens (NAc). Indeed, the excitability of DA neurons in the ventral tegmental area (VTA) is enhanced within hours of initial psychostimulant exposure. However, it is not known if this is accompanied by a comparably rapid change in the ability of cocaine to increase extracellular DA concentrations in the ventral striatum. To address this question we used fast-scan cyclic voltammetry (FSCV) in awake-behaving rats to measure DA responses in the NAc shell following an initial intravenous cocaine injection, and then again 2-h later. Both injections quickly elevated DA levels in the NAc shell, but the second cocaine infusion produced a greater effect than the first, indicating sensitization. This suggests that a single injection of cocaine induces sensitization-related plasticity very rapidly within the mesolimbic DA system. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Protective role of OH scavengers and DNA/chromatin organization in the induction of DNA breaks: mechanistic models and Monte Carlo simulations

    International Nuclear Information System (INIS)

    Ballarini, F.; Rossetti, M.; Scannicchio, D.; Jacob, P.; Molinelli, S.; Ottolenghi, A.; Volata, A.

    2003-01-01

    Radiation-induced DNA damage can be modulated by various factors, including the environment scavenging capacity (SC) and the DNA organization within the cell nucleus (chromatin compactness, DNA-binding proteins etc.). In this context the induction of ssb and dsb by photons and light ions of different energies impinging on different DNA structures (e.g. linear DNA, SV40 'minichromosomes' and cellular DNA) at different OH-radical SC values was modelled with the Monte Carlo PARTRAC code. Presently PARTRAC can transport electrons, photons, protons and alpha particles in liquid water with an 'event-by-event' approach, and can simulate the DNA content of mammalian cells with an 'atom-by-atom' description, from nucleotide pairs to chromatin fibre loops and chromosome territories. Energy depositions in the sugar-phosphate were considered as potential (direct) ssb. The production, diffusion and reaction of chemical species were explicitly simulated; reactions of OH radicals with the sugar-phosphate were assumed to lead to 'indirect' ssb with probability 65%. Two ssb on opposite strands within 10 bp were considered as a dsb. Yields of ssb and dsb/Gy/Dalton were calculated for different DNA structures as a function of the OH mean life time. By Zyuzikov, N.; Michael, B.D. (Gray Cancer Institute, (GB)); Wu, L. (Ch Zyuzdirect damage yields. In general, also depending on radiation quality, linear DNA was found to be more susceptible to strand breakage than SV40 minichromosomes, which in turn showed higher damage yields with respect to cellular DNA. The very good agreement found with available experimental data provided a validation of the model and allowed us to quantify separately the protective effect of OH scavengers and DNA/chromatin organization. Comparisons with data on nucleoids (DNA unfolded and depleted of histones) suggested that the experimental procedures used to obtain such targets might lower the environment SC, due to the loss of cellular scavenging compounds

  18. Induction of rapid and selective cell necrosis in Drosophila using Bacillus thuringiensis Cry toxin and its silkworm receptor

    OpenAIRE

    Obata, Fumiaki; Tanaka, Shiho; Kashio, Soshiro; Tsujimura, Hidenobu; Sato, Ryoichi; Miura, Masayuki

    2015-01-01

    Background Genetic ablation of target cells is a powerful tool to study the origins and functions of cells, tissue regeneration, or pathophysiology in a human disease model in vivo. Several methods for selective cell ablation by inducing apoptosis have been established, using exogenous toxins or endogenous proapoptotic genes. However, their application is limited to cells with intact apoptotic machinery. Results Herein, we established a method for inducing rapid and selective cell necrosis by...

  19. Method Development for Rapid Analysis of Natural Radioactive Nuclides Using Sector Field Inductively Coupled Plasma Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Lim, J.M.; Ji, Y.Y.; Lee, H.; Park, J.H.; Jang, M.; Chung, K.H.; Kang, M.J.; Choi, G.S. [Korea Atomic Energy Research Institute (Korea, Republic of)

    2014-07-01

    As an attempt to reduce the social costs and apprehension arising from radioactivity in the environment, an accurate and rapid assessment of radioactivity is highly desirable. Naturally occurring radioactive materials (NORM) are widely spread throughout the environment. The concern with radioactivity from these materials has therefore been growing for the last decade. In particular, radiation exposure in the industry when handling raw materials (e.g., coal mining and combustion, oil and gas production, metal mining and smelting, mineral sands (REE, Ti, Zr), fertilizer (phosphate), and building materials) has been brought to the public's attention. To decide the proper handling options, a rapid and accurate analytical method that can be used to evaluate the radioactivity of radionuclides (e.g., {sup 238}U, {sup 235}U, {sup 232}Th, {sup 226}Ra, and {sup 40}K) should be developed and validated. Direct measuring methods such as alpha spectrometry, a liquid scintillation counter (LSC), and mass-spectrometry are usually used for the measurement of radioactivity in NORM samples, and they encounter the most significant difficulties during pretreatment (e.g., purification, speciation, and dilution/enrichment). Since the pretreatment process consequently plays an important role in the measurement uncertainty, method development and validation should be performed. Furthermore, a-spectrometry has a major disadvantage of a long counting time, while it has a prominent measurement capability at a very low activity level of {sup 238}U, {sup 235}U, {sup 232}Th, and {sup 226}Ra. Contrary to the α-spectrometry method, a measurement technique using ICP-MS allow radioactivity in many samples to be measured in a short time period with a high degree of accuracy and precision. In this study, a method was developed for a rapid analysis of natural radioactive nuclides using ICP-MS. A sample digestion process was established using LiBO{sub 2} fusion and Fe co-precipitation. A magnetic

  20. The effects of nicardipine or esmolol on the onset time of rocuronium and intubation conditions during rapid sequence induction: a randomized double-blind trial.

    Science.gov (United States)

    Lee, Ji Heui; Kim, Yunkwang; Lee, Kye Hyeok; Rim, Sung Kyu; Lee, Ji Yeon; Lee, Cheong

    2015-06-01

    The main aims of rapid sequence induction (RSI) are prompt and adequate muscle relaxation for tracheal intubation and hemodynamic stability during and after intubation. The purpose of the present study was to investigate the effects of nicardipine and esmolol on the action of rocuronium and intubation conditions during RSI. Adult patients (n = 82) were randomly allocated to one of three groups. One minute prior to the induction of sevoflurane-based general anesthesia, patients received 20 μg/kg of nicardipine (N group; n = 27) or 0.5 mg/kg of esmolol (E group; n = 27), or 5 ml of saline (C group; n = 28). Patients were assessed according to intubation conditions, the onset time of rocuronium, mean arterial pressure (MAP), and heart rate (HR) during RSI. The intubation conditions and score were significantly better in the C and N groups than in the E group (P rocuronium was shortened in the N group and prolonged in the E group when compared to the C group (P rocuronium and attenuated changes in MAP after intubation. Esmolol may disturb intubation conditions and the onset of action of rocuronium, despite being effective in alleviating responses of HR after RSI.

  1. Rapid Determination of Plutonium Isotopes in Environmental Samples Using Sequential Injection Extraction Chromatography and Detection by Inductively Coupled Plasma Mass Spectrometry

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hou, Xiaolin; Roos, Per

    2009-01-01

    This article presents an automated method for the rapid determination of 239Pu and 240Pu in various environmental samples. The analytical method involves the in-line separation of Pu isotopes using extraction chromatography (TEVA) implemented in a sequential injection (SI) network followed...... by detection of isolated analytes with inductively coupled plasma mass spectrometry (ICP-MS). The method has been devised for the determination of Pu isotopes at environmentally relevant concentrations, whereby it has been successfully applied to the analyses of large volumes/amounts of samples, for example......, 100−200 g of soil and sediment, 20 g of seaweed, and 200 L of seawater following analyte preconcentration. The investigation of the separation capability of the assembled SI system revealed that up to 200 g of soil or sediment can be treated using a column containing about 0.70 g of TEVA resin...

  2. A rapid method for simultaneous determination of arsenic, cadmium and lead in drinking water by inductively coupled plasma mass spectrometry

    Directory of Open Access Journals (Sweden)

    Joshua Rey P. Torres

    Full Text Available The raw water source of drinking water in most areas in the Philippines is typically river water and in some cases groundwater. These sources are prone to elevated levels of metals and metalloids that may cause exposure of the general population when the treatment of the water is inadequate. This work presents a simple method based on EPA Method 200.8 for the determination of total concentrations of arsenic (As, cadmium (Cd and lead (Pb in drinking water using inductively coupled plasma-mass spectrometry (ICP-MS as the element-selective detector. This was applied in the determination of these elements in the water supply in Metro Manila, Philippines. The method detection limits were 0.095 μg L-1, 0.043 μg L-1, and 0.114 μg L-1 for total As, Cd and Pb, respectively.The method was validated using National Institute of Standards and Technology (NIST 1643e certified reference material for trace elements in water and determined values were 60.4 ± 0.5 μg L-1, 6.7 ± 0.1 μg L-1, and 19.6 ± 0.5 μg L-1 for As, Cd and Pb, respectively. These determined values were in good agreement with the certified values in the reference material. Analysis of actual drinking water samples showed that most samples did not exceed the limit of the Philippine drinking water standard for the elements.

  3. The Break

    DEFF Research Database (Denmark)

    Strand, Anete Mikkala Camille

    2018-01-01

    storytelling to enact fruitful breakings of patterns unbecoming. The claim being, that the hamster wheel of Work-life anno 2016 needs reconfiguration and the simple yet fruitful manner by which this is done is through acknowledging the benefits of bodies, spaces and artifacts – and the benefits of actually...... taking a break, discontinuing for a moment in order to continue better, wiser and more at ease. Both within and as part of the daily routines, and – now and then – outside these routines in the majesty of nature with time to explore and redirect the course of life in companionships with fellow man...

  4. A luminescent hybridoma-based biosensor for rapid detection of V. cholerae upon induction of calcium signaling pathway.

    Science.gov (United States)

    Zamani, Parichehr; Sajedi, Reza H; Hosseinkhani, Saman; Zeinoddini, Mehdi; Bakhshi, Bita

    2016-05-15

    In this study, a hybridoma based biosensor was developed for rapid, sensitive and selective detection of Vibrio cholerae O1 which converts the antibody-antigen binding to bioluminescence light. After investigation on hybridoma performance, the biosensor was constructed by transfecting specific hybridoma cells with aequorin reporter gene and the bioluminescence activities of stable biosensor were measured. The sensitivity of biosensor was as few as 50 CFU/ml and it showed no responses to other entric bacteria. Moreover, the response time of biosensor was estimated in 7th second which means this method is considerably faster than many available detection assays. In addition, this biosensor was successfully applied to V. cholerae detection in environmental samples with no significant loss in sensitivity, demonstrating our proposed biosensor provides a sensitive and reliable method for detection of V. cholerae in natural samples. The application of whole hybridoma cell directly as a sensing element in biosensor construction which mentioned for the first time in present study suggests that hybridoma cells could provide a valuable tool for future studies in both basic and diagnostic sciences and could be considered as a fast and specific sensing element for detection of other pathogens in different applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Characteristics and Influence to Fruit Distillates Quality of Rapid Induction of Ageing Character in the Presence of Mulberry Tree (Morus alba L. Wooden Chips

    Directory of Open Access Journals (Sweden)

    Elena MUDURA

    2016-11-01

    Full Text Available Research on rapid induction of ageing character to double distilled traditional fruit brandies, from Transylvania region was conducted. Mulberry tree chips were used as an alternative to traditional ageing in wooden barrels. The aim of this study was to highlight the factors influencing the chemical composition of fruit brandies, both depending on the type of the wood used and the transformations occurred during the heat treatment. Fruit distillates were produced after the traditional method – double distillation in copper alambic. The evaluation of the brandies consisted in analyzing the chemical parameters and the phenolic compounds after two months of ageing with wood chips. Results were compared with a control sample (unaged distillate, and found that during the ageing process volatile and non-volatile compounds were extracted significantly. The heat treatment influenced the chemical composition of the wooden chips. The chemical composition of finished products varied due to the composition of the wooden chips used and to the heat treatment applied. Evaluation of volatile and non-volatile compounds formed was carried out by comparison with the samples of the unaged distillate. It was demonstrated the improvement of chemical characteristics and polyphenolic compounds content, by rapidly inducing of the ageing character.

  6. DNA polymerase I-mediated repair of 365 nm-induced single-strand breaks in the DNA of Escherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    Ley, R D; Sedita, B A; Boye, E [Argonne National Lab., Ill. (USA)

    1978-03-01

    Irradiation of closed circular phage lambda DNA in vivo at 365 nm results in the induction of single-strand breaks and alkali-labile lesions at rates of 1.1 x 10/sup -14/ and 0.2 x 10/sup -14//dalton/J/m/sup 2/, respectively. The sum of the induction rates is similar to the rate of induction of single-strand breaks plus alkali-labile lesions (1 x 10/sup -14//dalton/J/m/sup 2/) observed in the E. coli genome. Postirradiation incubation of wild-type cells in buffer results in rapid repair of the breaks (up to 80% repaired in 10 min). No repair was observed in a DNA polymerase I-deficient mutant of E.coli.

  7. Comparison of the effect of rocuronium dosing based on corrected or lean body weight on rapid sequence induction and neuromuscular blockade duration in obese female patients

    Science.gov (United States)

    Sakızcı-Uyar, Bahar; Çelik, Şeref; Postacı, Aysun; Bayraktar, Yeşim; Dikmen, Bayazit; Özkoçak-Turan, Işıl; Saçan, Özlem

    2016-01-01

    Objectives: To compare onset time, duration of action, and tracheal intubation conditions in obese patients when the intubation dose of rocuronium was based on corrected body weight (CBW) versus lean body weight (LBW) for rapid sequence induction. Methods: This prospective study was carried out at Numune Education and Research Hospital, Ankara, Turkey between August 2013 and May 2014. Forty female obese patients scheduled for laparoscopic surgery under general anesthesia were randomized into 2 groups. Group CBW (n=20) received 1.2 mg/kg rocuronium based on CBW, and group LBW (n=20) received 1.2 mg/kg rocuronium based on LBW. Endotracheal intubation was performed 60 seconds after injection of muscle relaxant, and intubating conditions were evaluated. Neuromuscular transmission was monitored using acceleromyography of the adductor pollicis. Onset time, defined as time to depression of the twitch tension to 95% of its control value, and duration of action, defined as time to achieve one response to train-of-four stimulation (T1) were recorded. Results: No significant differences were observed between the groups in intubation conditions or onset time (50-60 seconds median, 30-30 interquartile range [IQR]). Duration of action was significantly longer in the CBW group (60 minutes median, 12 IQR) than the LBW group (35 minutes median, 16 IQR; procuronium based on LBW provides excellent or good tracheal intubating conditions within 60 seconds after administration and does not lead to prolonged duration of action. PMID:26739976

  8. A high-throughput solid-phase extraction microchip combined with inductively coupled plasma-mass spectrometry for rapid determination of trace heavy metals in natural water.

    Science.gov (United States)

    Shih, Tsung-Ting; Hsieh, Cheng-Chuan; Luo, Yu-Ting; Su, Yi-An; Chen, Ping-Hung; Chuang, Yu-Chen; Sun, Yuh-Chang

    2016-04-15

    Herein, a hyphenated system combining a high-throughput solid-phase extraction (htSPE) microchip with inductively coupled plasma-mass spectrometry (ICP-MS) for rapid determination of trace heavy metals was developed. Rather than performing multiple analyses in parallel for the enhancement of analytical throughput, we improved the processing speed for individual samples by increasing the operation flow rate during SPE procedures. To this end, an innovative device combining a micromixer and a multi-channeled extraction unit was designed. Furthermore, a programmable valve manifold was used to interface the developed microchip and ICP-MS instrumentation in order to fully automate the system, leading to a dramatic reduction in operation time and human error. Under the optimized operation conditions for the established system, detection limits of 1.64-42.54 ng L(-1) for the analyte ions were achieved. Validation procedures demonstrated that the developed method could be satisfactorily applied to the determination of trace heavy metals in natural water. Each analysis could be readily accomplished within just 186 s using the established system. This represents, to the best of our knowledge, an unprecedented speed for the analysis of trace heavy metal ions. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Rapid sequence induction of anesthesia

    OpenAIRE

    Moro, Eduardo Toshiyuki; Módolo, Norma Sueli Pinheiro [UNESP

    2004-01-01

    JUSTIFICATIVA E OBJETIVOS: A indução da anestesia por meio da técnica de seqüência rápida é utilizada, principalmente, para proteger as vias aéreas, quando há risco de aspiração do conteúdo gástrico. O objetivo deste artigo é revisar a técnica e os diferentes protocolos que buscam o uso racional dos fármacos disponíveis, visando condições ideais de intubação traqueal, sem aumentar o risco de aspiração do conteúdo gástrico ou de outras complicações. CONTEÚDO: Apresenta uma revisão da técnica d...

  10. Breaking away.

    Science.gov (United States)

    Innes, G M; Sosnow, P L

    1995-05-01

    While life as hospital employees was comfortable, the lure of independence won out for these two emergency department physicians. Breaking away to develop a new company was not easy, but it's paid off for the entrepreneurs of the Capital Region Emergency Medicine, P.C. Developing an emergency medicine business meant learning all aspects of business: billing services, evaluating legal services, raising capital, and becoming employers. The advantage has been an ability to use profits to improve the moral of staff, an increase in salary, and an overall sense of satisfaction.

  11. In vivo quantification of DNA double strand breaks

    International Nuclear Information System (INIS)

    Simonsson, M.; Qvarnstroem, F.; Turesson, I.; Johansson, K.-A.; Nyman, J.; Hermansson, I.; Oden, A.; Book, M.

    2003-01-01

    DNA double strand breaks (DSBs) can be introduced in the genome by exposure to exogenous agents such as ionising radiation and radio-mimetic chemicals. The biological importance of these breaks is significant even at low numbers. Inaccurate repair or lack of repair of a single DSB has the potential to kill a cell or lead to tumourigenesis. Thus the induction and repair of DSBs are crucial events in the onset of malignancies. Following the induction of DSBs, the core histone H2AX is rapidly phosphorylated at residue serine 139. This phosphorylated form of H2AX is referred to as gH2AX. Histones wrapped in megabase regions flanking these breaks are involved in this process, which results in the formation of discrete nuclear foci. It has previously been shown that a single DSB is sufficient to produce a detectable focus. So far there has been a lack of methods capable of measuring the amount of DSBs at clinically relevant quantities. Such a method would embrace a wide field of applications. It could be applied as a biological dosimeter when studying carcinogenic effects and provide the basis for an assay predicting individual radiosensitivity. We describe a measurement procedure that detects and quantifies small amounts of DSBs in vivo. This is accomplished using immunofluorescence detection of the molecular marker gH2AX. The gH2AX foci are quantified in histological sections using basic digital image analysis methods as the main component. In a primary assessment of the procedure we analysed the in vivo dose response of prostate cancer patients in clinical practice undergoing radiotherapy. Epidermal nucleated cells in skin biopsies taken 30 minutes following the first single dose delivered show linear dose response for low doses ranging from 0 - 1.2 Gy. The described procedure for double strand break quantification can detect dose changes as low as 0.18 Gy

  12. The Break

    DEFF Research Database (Denmark)

    Strand, Anete Mikkala Camille; Larsen, Jens

    2015-01-01

    the challenges of the million-dollar question is stemming from the ‘bets on the future’ – or what David Boje coins as ‘antenarratives’, (Boje, 2008) that emerged through various reconfiguring story actions, on two different occasions. The paper thus elaborates on two cases of restorying events; One taking place...... that language and the social has been granted too much power on the dispense of the bodily, physical and biological – or in short, in dispense of the material. The break To be or not to be poses the theoretical notion of dis-/continuity (Barad, 2007, 2010) from the quantum approach to storytelling (Strand 2012...... in their use of the communicative platform of Object theatre from the methodology of Material Storytelling (Strand 2012). The Bets on the Future piece discusses the extend to which the cases of using this kind of technologies may provide fruitful ‘bets on the future’ in regard to the million-dollar question...

  13. Rapid identification of tomato Sw-5 resistance-breaking isolates of Tomato spotted wilt virus using high resolution melting and TaqMan SNP Genotyping assays as allelic discrimination techniques.

    Directory of Open Access Journals (Sweden)

    Valentina di Rienzo

    Full Text Available In tomato, resistance to Tomato spotted wilt virus (TSWV is conferred by the dominant gene, designated Sw-5. Virulent Sw-5 resistance breaking (SRB mutants of TSWV have been reported on Sw-5 tomato cultivars. Two different PCR-based allelic discrimination techniques, namely Custom TaqMan™ SNP Genotyping and high-resolution melting (HRM assays, were developed and compared for their ability to distinguish between avirulent (Sw-5 non-infecting, SNI and SRB biotypes. TaqMan assays proved to be more sensitive (threshold of detection in a range of 50-70 TSWV RNA copies and more reliable than HRM, assigning 25 TSWV isolates to their correct genotype with an accuracy of 100%. Moreover, the TaqMan SNP assays were further improved developing a rapid and simple protocol that included crude leaf extraction for RNA template preparations. On the other hand, HRM assays showed higher levels of sensitivity than TaqMan when used to co-detect both biotypes in different artificial mixtures. These diagnostic assays contributed to gain preliminary information on the epidemiology of TSWV isolates in open field conditions. In fact, the presented data suggest that SRB isolates are present as stable populations established year round, persisting on both winter (globe artichoke and summer (tomato crops, in the same cultivated areas of Southern Italy.

  14. Phyllosphere yeasts rapidly break down biodegradable plastics

    OpenAIRE

    Kitamoto, Hiroko K; Shinozaki, Yukiko; Cao, Xiao-hong; Morita, Tomotake; Konishi, Masaaki; Tago, Kanako; Kajiwara, Hideyuki; Koitabashi, Motoo; Yoshida, Shigenobu; Watanabe, Takashi; Sameshima-Yamashita, Yuka; Nakajima-Kambe, Toshiaki; Tsushima, Seiya

    2011-01-01

    The use of biodegradable plastics can reduce the accumulation of environmentally persistent plastic wastes. The rate of degradation of biodegradable plastics depends on environmental conditions and is highly variable. Techniques for achieving more consistent degradation are needed. However, only a few microorganisms involved in the degradation process have been isolated so far from the environment. Here, we show that Pseudozyma spp. yeasts, which are common in the phyllosphere and are easily ...

  15. Phyllosphere yeasts rapidly break down biodegradable plastics.

    Science.gov (United States)

    Kitamoto, Hiroko K; Shinozaki, Yukiko; Cao, Xiao-Hong; Morita, Tomotake; Konishi, Masaaki; Tago, Kanako; Kajiwara, Hideyuki; Koitabashi, Motoo; Yoshida, Shigenobu; Watanabe, Takashi; Sameshima-Yamashita, Yuka; Nakajima-Kambe, Toshiaki; Tsushima, Seiya

    2011-11-29

    The use of biodegradable plastics can reduce the accumulation of environmentally persistent plastic wastes. The rate of degradation of biodegradable plastics depends on environmental conditions and is highly variable. Techniques for achieving more consistent degradation are needed. However, only a few microorganisms involved in the degradation process have been isolated so far from the environment. Here, we show that Pseudozyma spp. yeasts, which are common in the phyllosphere and are easily isolated from plant surfaces, displayed strong degradation activity on films made from poly-butylene succinate or poly-butylene succinate-co-adipate. Strains of P. antarctica isolated from leaves and husks of paddy rice displayed strong degradation activity on these films at 30°C. The type strain, P. antarctica JCM 10317, and Pseudozyma spp. strains from phyllosphere secreted a biodegradable plastic-degrading enzyme with a molecular mass of about 22 kDa. Reliable source of biodegradable plastic-degrading microorganisms are now in our hands.

  16. Phyllosphere yeasts rapidly break down biodegradable plastics

    Science.gov (United States)

    2011-01-01

    The use of biodegradable plastics can reduce the accumulation of environmentally persistent plastic wastes. The rate of degradation of biodegradable plastics depends on environmental conditions and is highly variable. Techniques for achieving more consistent degradation are needed. However, only a few microorganisms involved in the degradation process have been isolated so far from the environment. Here, we show that Pseudozyma spp. yeasts, which are common in the phyllosphere and are easily isolated from plant surfaces, displayed strong degradation activity on films made from poly-butylene succinate or poly-butylene succinate-co-adipate. Strains of P. antarctica isolated from leaves and husks of paddy rice displayed strong degradation activity on these films at 30°C. The type strain, P. antarctica JCM 10317, and Pseudozyma spp. strains from phyllosphere secreted a biodegradable plastic-degrading enzyme with a molecular mass of about 22 kDa. Reliable source of biodegradable plastic-degrading microorganisms are now in our hands. PMID:22126328

  17. Breaking out or breaking down.

    Science.gov (United States)

    Brown, L R; Halweil, B

    1999-01-01

    A new kind of challenge looms in several regions of the world, where the historic trend toward longer life expectancy has been sharply reversed. There are three clearly identifiable trends that are causing death rates to increase. The first is the spread of the HIV virus, which causes AIDS. As illustrated by the case of sub-Saharan Africa, the growth of the HIV epidemic damages a nation's social infrastructure, producing lingering demographic and economic effects. It reinforces conditions like poverty, illiteracy, and malnutrition. Second, the depletion of aquifers has become a major threat, particularly in India, where water tables are falling in almost every region. Water shortage leads to such problems as infectious diseases, waterborne microbes, and weakened water irrigation for farmers, which in turn leads to a diminishment of the food supply. The third threat that hangs over the future of nearly all countries where rapid population growth continues is the decline in the amount of cropland per person; this is a threat arising as a consequence of population growth and of the conversion of cropland to other uses. Land scarcity readily translates into malnutrition, hunger, rising mortality, and migration. In order to face all of these threats, leaders all over the world will need to understand that universal access to family planning is not only important for coping with resource scarcity and the spread of HIV/AIDS but is also likely to improve the quality of life for citizens of their countries.

  18. Unification of SUSY breaking and GUT breaking

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Tatsuo [Department of Physics, Hokkaido University,Sapporo 060-0810 (Japan); Omura, Yuji [Department of Physics, Nagoya University,Nagoya 464-8602 (Japan)

    2015-02-18

    We build explicit supersymmetric unification models where grand unified gauge symmetry breaking and supersymmetry (SUSY) breaking are caused by the same sector. Besides, the SM-charged particles are also predicted by the symmetry breaking sector, and they give the soft SUSY breaking terms through the so-called gauge mediation. We investigate the mass spectrums in an explicit model with SU(5) and additional gauge groups, and discuss its phenomenological aspects. Especially, nonzero A-term and B-term are generated at one-loop level according to the mediation via the vector superfields, so that the electro-weak symmetry breaking and 125 GeV Higgs mass may be achieved by the large B-term and A-term even if the stop mass is around 1 TeV.

  19. Radiation-induced double-strand breaks in mammalian DNA: influence of temperature and DMSO.

    Science.gov (United States)

    Elmroth, K; Nygren, J; Erkell, L J; Hultborn, R

    2000-11-01

    To investigate the effects of subphysiological irradiation temperature (2 28 degrees C) and the influence of the radical scavenger DMSO on the induction of double-strand breaks (DSB) in chromosomal DNA from a human breast cancer cell line (MCF-7) as well as in intact cells. The rejoining of DSB in cells irradiated at 2 degrees C or 37 degrees C was also investigated. Agarose plugs with [14C]thymidine labelled MCF-7 cells were lysed in EDTA-NLS-proteinase-K buffer. The plugs containing chromosomal DNA were irradiated with X-rays under different temperatures and scavenging conditions. Intact MCF-7 cells were irradiated in Petri dishes and plugs were made. The cells were then lysed in EDTA-NLS-proteinase-K buffer. The induction of DSB was studied by constant field gel electrophoresis and expressed as DSB/100/Mbp, calculated from the fraction of activity released into the gel. The induction of DSB in chromosomal DNA was reduced by a decrease in temperature. This protective effect of low temperature was inhibited when the DNA was irradiated in the presence of DMSO. No difference was found when intact cells were irradiated at different temperatures. However, the rapid phase of rejoining was slower in cells irradiated at 37 degrees C than at 2 degrees C. The induction of DSB in naked DNA was reduced by hypothermic irradiation. The temperature had no influence on the induction of DSB in the presence of a high concentration of DMSO, indicating that the temperature effect is mediated via the indirect effects of ionizing radiation. Results are difficult to interpret in intact cells. Rejoining during irradiation at the higher temperature may counteract an increased induction. The difference in rejoining may be interpreted in terms of qualitative differences between breaks induced at the two temperatures.

  20. Poly(4-vinylphenol gate insulator with cross-linking using a rapid low-power microwave induction heating scheme for organic thin-film-transistors

    Directory of Open Access Journals (Sweden)

    Ching-Lin Fan

    2016-03-01

    Full Text Available A Microwave-Induction Heating (MIH scheme is proposed for the poly(4-vinylphenol (PVP gate insulator cross-linking process to replace the traditional oven heating cross-linking process. The cross-linking time is significantly decreased from 1 h to 5 min by heating the metal below the PVP layer using microwave irradiation. The necessary microwave power was substantially reduced to about 50 W by decreasing the chamber pressure. The MIH scheme is a good candidate to replace traditional thermal heating for cross-linking of PVP as the gate insulator for organic thin-film-transistors.

  1. Poly(4-vinylphenol) gate insulator with cross-linking using a rapid low-power microwave induction heating scheme for organic thin-film-transistors

    Science.gov (United States)

    Fan, Ching-Lin; Shang, Ming-Chi; Hsia, Mao-Yuan; Wang, Shea-Jue; Huang, Bohr-Ran; Lee, Win-Der

    2016-03-01

    A Microwave-Induction Heating (MIH) scheme is proposed for the poly(4-vinylphenol) (PVP) gate insulator cross-linking process to replace the traditional oven heating cross-linking process. The cross-linking time is significantly decreased from 1 h to 5 min by heating the metal below the PVP layer using microwave irradiation. The necessary microwave power was substantially reduced to about 50 W by decreasing the chamber pressure. The MIH scheme is a good candidate to replace traditional thermal heating for cross-linking of PVP as the gate insulator for organic thin-film-transistors.

  2. Labor Induction

    Science.gov (United States)

    f AQ FREQUENTLY ASKED QUESTIONS FAQ154 LABOR, DELIVERY, AND POSTPARTUM CARE Labor Induction • What is labor induction? • Why is labor induced? • What is the Bishop score? • What is “ripening ...

  3. Induction linacs

    International Nuclear Information System (INIS)

    Keefe, D.

    1986-07-01

    The principle of linear induction acceleration is described, and examples are given of practical configurations for induction linacs. These examples include the Advanced Technology Accelerator, Long Pulse Induction Linac, Radial Line Accelerator (RADLAC), and Magnetically-Insulated Electron-Focussed Ion Linac. A related concept, the auto accelerator, is described in which the high-current electron-beam technology in the sub-10 MeV region is exploited to produce electron beams at energies perhaps as high as the 100 to 1000 MeV range. Induction linacs for ions are also discussed. The efficiency of induction linear acceleration is analyzed

  4. Research progress on dam-break floods

    KAUST Repository

    Wu, Jiansong; Bao, Kai; Zhang, Hui

    2011-01-01

    Because of the catastrophic effects downstream of dam-break failure, more and more researchers around the world have been working on the study of dam-break flows to accurately forecast the downstream inundation mapping. With the rapid development of computer hardware and computing techniques, numerical study on dam-break flows has been a popular research subject. In the paper, the numerical methodologies used to solve the governing partial differential equations of dam-break flows are classified and summarized, and their characteristics and applications are discussed respectively. Furthermore, the fully-developed mathematical models developed in recent decades are reviewed, and also introduced the authors' on-going work. Finally, some possible future developments on modeling the dam-break flows and some solutions are presented and discussed. © 2011 IEEE.

  5. Research progress on dam-break floods

    KAUST Repository

    Wu, Jiansong

    2011-08-01

    Because of the catastrophic effects downstream of dam-break failure, more and more researchers around the world have been working on the study of dam-break flows to accurately forecast the downstream inundation mapping. With the rapid development of computer hardware and computing techniques, numerical study on dam-break flows has been a popular research subject. In the paper, the numerical methodologies used to solve the governing partial differential equations of dam-break flows are classified and summarized, and their characteristics and applications are discussed respectively. Furthermore, the fully-developed mathematical models developed in recent decades are reviewed, and also introduced the authors\\' on-going work. Finally, some possible future developments on modeling the dam-break flows and some solutions are presented and discussed. © 2011 IEEE.

  6. Road infrastructure and demand induction

    DEFF Research Database (Denmark)

    Nielsen, Thomas Alexander Sick; Hovgesen, Henrik Harder; Lahrmann, Harry

    2006-01-01

    a long screenline is used to measure the development in aggregate demand in selected corridors. The paper analyses demand induction by establishing time series of aggregate demand that is compared with the national traffic index. Significant trend breaks in the association between aggregate demand...... in the corridors and the national index, following the opening of motorways or bridges, indicates demand induction by infrastructure expansion in a number of instances. Lack of significant trend breaks following opening year is found in peripheral areas where major population centres are missing. This indicates...... the necessity of some latent demand within suitable travel range for new infrastructure elements to produce significant amounts of induced demand. Estimates of demand induction as a percentage of the realised demand five years after opening are between 10% and 67% for new motorway sections depending...

  7. Cytotoxicity and genotoxicity of a monazite component: lanthanum effects on the viability and induction of breaks in the DNA of human lymphocytes; Citotoxicidade e genotoxicidade de um componente da monazita: efeitos do lantanio na viabilidade e inducao de quebras no DNA de linfocitos humanos

    Energy Technology Data Exchange (ETDEWEB)

    Paiva, Amanda Valle de Almeida

    2007-07-01

    The Monazite is a mineral extracted from open mines. It is constituted by lanthanum element aggregated with cerium, yttrium and thorium [(Ce, La, Y, Th)PO{sub 4}]. Lanthanum (La) is a rare-earth metal with applications in agriculture, industry and medicine. Since lanthanides and their compounds show a broad spectrum of applications there is an increased risk of incorporation in human. Inhalation of aerosols containing La is the main route of incorporation in workers exposed to several chemical forms of La. Herein, we examined the effect of lanthanum nitrate - La(NO{sub 3}){sub 3} in human lymphocytes. JURKAT cells and human peripheral lymphocytes (HPL) were used to evaluate the effect of La(NO{sub 3}){sub 3} on viability (apoptosis or necrosis) and DNA strand breaks induction or/and alkali-labile sites (ALS). We demonstrate that La has a cytotoxic and genotoxic effect on both cell lines. The results indicate that necrosis is the pathway by which La(NO{sub 3}){sub 3} induces cytotoxicity. The vitamin E is able to diminish DNA strand breaks induced by La(NO{sub 3}){sub 3} suggesting that reactive oxygen species (ROS) may be involved in the genotoxic process. (author)

  8. Duality after supersymmetry breaking

    International Nuclear Information System (INIS)

    Shadmi, Yael; Cheng, Hsin-Chia

    1998-05-01

    Starting with two supersymmetric dual theories, we imagine adding a chiral perturbation that breaks supersymmetry dynamically. At low energy we then get two theories with soft supersymmetry-breaking terms that are generated dynamically. With a canonical Kaehler potential, some of the scalars of the ''magnetic'' theory typically have negative mass-squared, and the vector-like symmetry is broken. Since for large supersymmetry breaking the ''electric'' theory becomes ordinary QCD, the two theories are then incompatible. For small supersymmetry breaking, if duality still holds, the magnetic theory analysis implies specific patterns of chiral symmetry breaking in supersymmetric QCD with small soft masses

  9. The administration sequence of propofol and remifentanil does not affect the ED50 and ED95 of rocuronium in rapid sequence induction of anesthesia: a double-blind randomized controlled trial.

    Science.gov (United States)

    Ozcelik, M; Guclu, C; Bermede, O; Baytas, V; Altay, N; Karahan, M A; Erdogan, B; Can, O

    2016-04-01

    The topic of drug administration sequence in rapid sequence induction (RSI) is still an object of interest in terms of rocuronium effectiveness. The aim of this prospective, randomized trial was to evaluate the effect of administration sequence of propofol and remifentanil on ED50 and ED95 of rocuronium in a RSI model. Eighty-four patients were randomized into Group Remifentanil (Group R, n = 43), where induction of general anesthesia started with remifentanil (2 µg/kg) and followed by propofol (2 mg/kg) and rocuronium administrations; and Group Propofol (Group P, n = 41), where induction of general anesthesia started with propofol and followed by remifentanil and rocuronium. First patients in each group were paralyzed by 0.8 mg/kg rocuronium. In case of acceptable intubation as evaluated according to the criteria described by Viby-Mogensen et al, rocuronium dose was decreased by 0.1 mg/kg for the next patient; otherwise, rocuronium dose was increased by 0.1 mg/kg. After three crossover points, increments or decrements in rocuronium dosage were set to 0.05 mg/kg. The process was repeated until a total of ten crossover points were obtained. The ED50 and ED95 doses of rocuronium were similar in Group R (0.182 mg/kg, and 0.244 mg/kg, respectively) and Group P (0.121 mg/kg, and 0.243 mg/kg, respectively) according to 95% CI of the estimates. There was no statistically significant difference in terms of clinically acceptable intubation conditions between the two groups (56.1% in Group R vs. 59% in Group P, p = 0.795). The choice of administration sequence of propofol and remifentanil does not have an impact on estimated ED50 and ED95 of rocuronium in providing acceptable intubation conditions in the RSI technique.

  10. Inductive reasoning.

    Science.gov (United States)

    Hayes, Brett K; Heit, Evan; Swendsen, Haruka

    2010-03-01

    Inductive reasoning entails using existing knowledge or observations to make predictions about novel cases. We review recent findings in research on category-based induction as well as theoretical models of these results, including similarity-based models, connectionist networks, an account based on relevance theory, Bayesian models, and other mathematical models. A number of touchstone empirical phenomena that involve taxonomic similarity are described. We also examine phenomena involving more complex background knowledge about premises and conclusions of inductive arguments and the properties referenced. Earlier models are shown to give a good account of similarity-based phenomena but not knowledge-based phenomena. Recent models that aim to account for both similarity-based and knowledge-based phenomena are reviewed and evaluated. Among the most important new directions in induction research are a focus on induction with uncertain premise categories, the modeling of the relationship between inductive and deductive reasoning, and examination of the neural substrates of induction. A common theme in both the well-established and emerging lines of induction research is the need to develop well-articulated and empirically testable formal models of induction. Copyright © 2010 John Wiley & Sons, Ltd. For further resources related to this article, please visit the WIREs website. Copyright © 2010 John Wiley & Sons, Ltd.

  11. A rapid and reliable method for Pb isotopic analysis of peat and lichens by laser ablation-quadrupole-inductively coupled plasma-mass spectrometry for biomonitoring and sample screening

    International Nuclear Information System (INIS)

    Kylander, M.E.; Weiss, D.J.; Jeffries, T.E.; Kober, B.; Dolgopolova, A.; Garcia-Sanchez, R.; Coles, B.J.

    2007-01-01

    An analytical protocol for rapid and reliable laser ablation-quadrupole (LA-Q)- and multi-collector (MC-) inductively coupled plasma-mass spectrometry (ICP-MS) analysis of Pb isotope ratios ( 207 Pb/ 206 Pb and 208 Pb/ 206 Pb) in peats and lichens is developed. This technique is applicable to source tracing atmospheric Pb deposition in biomonitoring studies and sample screening. Reference materials and environmental samples were dry ashed and pressed into pellets for introduction by laser ablation. No binder was used to reduce contamination. LA-MC-ICP-MS internal and external precisions were 207 Pb/ 206 Pb and 208 Pb/ 206 Pb ratios. LA-Q-ICP-MS internal precisions on 207 Pb/ 206 Pb and 208 Pb/ 206 Pb ratios were lower with values for the different sample sets 208 Pb by Q-ICP-MS are identified as sources of reduced analytical performance

  12. A rapid procedure for the determination of thorium, uranium, cadmium and molybdenum in small sediment samples by inductively coupled plasma-mass spectrometry: application in Chesapeake Bay

    International Nuclear Information System (INIS)

    Zheng, Y.; Weinman, B.; Cronin, T.; Fleisher, M.Q.; Anderson, R.F.

    2003-01-01

    This paper describes a rapid procedure that allows precise analysis of Mo, Cd, U and Th in sediment samples as small as 10 mg by using a novel approach that utilizes a 'pseudo' isotope dilution for Th and conventional isotope dilution for Mo, Cd and U by ICP-MS. Long-term reproducibility of the method is between 2.5 and 5% with an advantage of rapid analysis on a single digestion of sediment sample and the potential of adding other elements of interest if so desired. Application of this method to two piston cores collected near the mouth of the Patuxent River in Chesapeake Bay showed that the accumulation of authigenic Mo and Cd varied in response to the changing bottom water redox conditions, with anoxia showing consistent oscillations throughout both pre-industrial and industrial times. Accumulation of authigenic U shows consistent oscillations as well, without any apparent increase in productivity related to anoxic trends. Degrees of Mo and Cd enrichment also inversely correlate to halophilic microfaunal assemblages already established as paleoclimate proxies within the bay indicating that bottom water anoxia is driven in part by the amount of freshwater discharge that the area receives

  13. The effect of dimethyl sulfoxide on the induction of DNA strand breaks in plasmid DNA and colony formation of PC Cl3 mammalian cells by alpha-, beta-, and Auger electron emitters (223)Ra, (188)Re, and (99m)Tc.

    Science.gov (United States)

    Runge, Roswitha; Oehme, Liane; Kotzerke, Jörg; Freudenberg, Robert

    2016-12-01

    DNA damage occurs as a consequence of both direct and indirect effects of ionizing radiation. The severity of DNA damage depends on the physical characteristics of the radiation quality, e.g., the linear energy transfer (LET). There are still contrary findings regarding direct or indirect interactions of high-LET emitters with DNA. Our aim is to determine DNA damage and the effect on cellular survival induced by (223)Ra compared to (188)Re and (99m)Tc modulated by the radical scavenger dimethyl sulfoxide (DMSO). Radioactive solutions of (223)Ra, (188)Re, or (99m)Tc were added to either plasmid DNA or to PC Cl3 cells in the absence or presence of DMSO. Following irradiation, single strand breaks (SSB) and double strand breaks (DSB) in plasmid DNA were analyzed by gel electrophoresis. To determine the radiosensitivity of the rat thyroid cell line (PC Cl3), survival curves were performed using the colony formation assay. Exposure to 120 Gy of (223)Ra, (188)Re, or (99m)Tc leads to maximal yields of SSB (80 %) in plasmid DNA. Irradiation with 540 Gy (223)Ra and 500 Gy (188)Re or (99m)Tc induced 40, 28, and 64 % linear plasmid conformations, respectively. DMSO prevented the SSB and DSB in a similar way for all radionuclides. However, with the α-emitter (223)Ra, a low level of DSB could not be prevented by DMSO. Irradiation of PC Cl3 cells with (223)Ra, (188)Re, and (99m)Tc pre-incubated with DMSO revealed enhanced survival fractions (SF) in comparison to treatment without DMSO. Protection factors (PF) were calculated using the fitted survival curves. These factors are 1.23 ± 0.04, 1.20 ± 0.19, and 1.34 ± 0.05 for (223)Ra, (188)Re, and (99m)Tc, respectively. For (223)Ra, as well as for (188)Re and (99m)Tc, dose-dependent radiation effects were found applicable for plasmid DNA and PC Cl3 cells. The radioprotection by DMSO was in the same range for high- and low-LET emitter. Overall, the results indicate the contribution of mainly indirect radiation

  14. Rapid Induction of Cerebral Organoids From Human Induced Pluripotent Stem Cells Using a Chemically Defined Hydrogel and Defined Cell Culture Medium.

    Science.gov (United States)

    Lindborg, Beth A; Brekke, John H; Vegoe, Amanda L; Ulrich, Connor B; Haider, Kerri T; Subramaniam, Sandhya; Venhuizen, Scott L; Eide, Cindy R; Orchard, Paul J; Chen, Weili; Wang, Qi; Pelaez, Francisco; Scott, Carolyn M; Kokkoli, Efrosini; Keirstead, Susan A; Dutton, James R; Tolar, Jakub; O'Brien, Timothy D

    2016-07-01

    Tissue organoids are a promising technology that may accelerate development of the societal and NIH mandate for precision medicine. Here we describe a robust and simple method for generating cerebral organoids (cOrgs) from human pluripotent stem cells by using a chemically defined hydrogel material and chemically defined culture medium. By using no additional neural induction components, cOrgs appeared on the hydrogel surface within 10-14 days, and under static culture conditions, they attained sizes up to 3 mm in greatest dimension by day 28. Histologically, the organoids showed neural rosette and neural tube-like structures and evidence of early corticogenesis. Immunostaining and quantitative reverse-transcription polymerase chain reaction demonstrated protein and gene expression representative of forebrain, midbrain, and hindbrain development. Physiologic studies showed responses to glutamate and depolarization in many cells, consistent with neural behavior. The method of cerebral organoid generation described here facilitates access to this technology, enables scalable applications, and provides a potential pathway to translational applications where defined components are desirable. Tissue organoids are a promising technology with many potential applications, such as pharmaceutical screens and development of in vitro disease models, particularly for human polygenic conditions where animal models are insufficient. This work describes a robust and simple method for generating cerebral organoids from human induced pluripotent stem cells by using a chemically defined hydrogel material and chemically defined culture medium. This method, by virtue of its simplicity and use of defined materials, greatly facilitates access to cerebral organoid technology, enables scalable applications, and provides a potential pathway to translational applications where defined components are desirable. ©AlphaMed Press.

  15. Teacher induction

    NARCIS (Netherlands)

    Beijaard, D.; Buitink, J.; Kessels, C.; Peterson, P.; Baker, E.; McGraw, B.

    2010-01-01

    Teacher induction programs are intended to support the professional development of beginning teachers and thereby contribute to the reduction of teacher attrition during the early teaching years. Teacher induction programs are often based upon a deficit model with a focus on the better organization

  16. Bubbles and breaking waves

    Science.gov (United States)

    Thorpe, S. A.

    1980-01-01

    The physical processes which control the transfer of gases between the atmosphere and oceans or lakes are poorly understood. Clouds of micro-bubbles have been detected below the surface of Loch Ness when the wind is strong enough to cause the waves to break. The rate of transfer of gas into solution from these bubbles is estimated to be significant if repeated on a global scale. We present here further evidence that the bubbles are caused by breaking waves, and discuss the relationship between the mean frequency of wave breaking at a fixed point and the average distance between breaking waves, as might be estimated from an aerial photograph.

  17. MO-FG-CAMPUS-TeP3-02: Benchmarks of a Proton Relative Biological Effectiveness (RBE) Model for DNA Double Strand Break (DSB) Induction in the FLUKA, MCNP, TOPAS, and RayStation™ Treatment Planning System

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, R [University of Washington, Seattle, WA (United States); Streitmatter, S [University of Utah Hospitals, Salt Lake City, UT (United States); Traneus, E [RAYSEARCH LABORATORIES AB, Stockholm (Sweden); Moskvin, V [St. Jude Children’s Hospital, Memphis, TN (United States); Schuemann, J [Massachusetts General Hospital, Boston, MA (United States)

    2016-06-15

    Purpose: Validate implementation of a published RBE model for DSB induction (RBEDSB) in several general purpose Monte Carlo (MC) code systems and the RayStation™ treatment planning system (TPS). For protons and other light ions, DSB induction is a critical initiating molecular event that correlates well with the RBE for cell survival. Methods: An efficient algorithm to incorporate information on proton and light ion RBEDSB from the independently tested Monte Carlo Damage Simulation (MCDS) has now been integrated into MCNP (Stewart et al. PMB 60, 8249–8274, 2015), FLUKA, TOPAS and a research build of the RayStation™ TPS. To cross-validate the RBEDSB model implementation LET distributions, depth-dose and lateral (dose and RBEDSB) profiles for monodirectional monoenergetic (100 to 200 MeV) protons incident on a water phantom are compared. The effects of recoil and secondary ion production ({sub 2}H{sub +}, {sub 3}H{sub +}, {sub 3}He{sub 2+}, {sub 4}He{sub 2+}), spot size (3 and 10 mm), and transport physics on beam profiles and RBEDSB are examined. Results: Depth-dose and RBEDSB profiles among all of the MC models are in excellent agreement using a 1 mm distance criterion (width of a voxel). For a 100 MeV proton beam (10 mm spot), RBEDSB = 1.2 ± 0.03 (− 2–3%) at the tip of the Bragg peak and increases to 1.59 ± 0.3 two mm distal to the Bragg peak. RBEDSB tends to decrease as the kinetic energy of the incident proton increases. Conclusion: The model for proton RBEDSB has been accurately implemented into FLUKA, MCNP, TOPAS and the RayStation™TPS. The transport of secondary light ions (Z > 1) has a significant impact on RBEDSB, especially distal to the Bragg peak, although light ions have a small effect on (dosexRBEDSB) profiles. The ability to incorporate spatial variations in proton RBE within a TPS creates new opportunities to individualize treatment plans and increase the therapeutic ratio. Dr. Erik Traneus is employed full-time as a Research Scientist

  18. Rapid isolation of plutonium in environmental solid samples using sequential injection anion exchange chromatography followed by detection with inductively coupled plasma mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Qiao Jixin, E-mail: jixin.qiao@risoe.d [Radiation Research Division, Riso National Laboratory for Sustainable Energy, Technical University of Denmark, DK-4000 Roskilde (Denmark); Hou Xiaolin; Roos, Per [Radiation Research Division, Riso National Laboratory for Sustainable Energy, Technical University of Denmark, DK-4000 Roskilde (Denmark); Miro, Manuel [Department of Chemistry, Faculty of Sciences, University of the Balearic Islands, Carretera de Valldemossa km. 7.5, E-07122 Palma de Mallorca, Illes Balears (Spain)

    2011-01-31

    This paper reports an automated analytical method for rapid determination of plutonium isotopes ({sup 239}Pu and {sup 240}Pu) in environmental solid extracts. Anion exchange chromatographic columns were incorporated in a sequential injection (SI) system to undertake the automated separation of plutonium from matrix and interfering elements. The analytical results most distinctly demonstrated that the crosslinkage of the anion exchanger is a key parameter controlling the separation efficiency. AG 1-x4 type resin was selected as the most suitable sorbent material for analyte separation. Investigation of column size effect upon the separation efficiency revealed that small-sized (2 mL) columns sufficed to handle up to 50 g of environmental soil samples. Under the optimum conditions, chemical yields of plutonium exceeded 90% and the decontamination factors for uranium, thorium and lead ranged from 10{sup 3} to 10{sup 4}. The determination of plutonium isotopes in three standard/certified reference materials (IAEA-375 soil, IAEA-135 sediment and NIST-4359 seaweed) and two reference samples (Irish Sea sediment and Danish soil) revealed a good agreement with reference/certified values. The SI column-separation method is straightforward and less labor intensive as compared with batch-wise anion exchange chromatographic procedures. Besides, the automated method features low consumption of ion-exchanger and reagents for column washing and elution, with the consequent decrease in the generation of acidic waste, thus bearing green chemical credentials.

  19. Investigation of Rapid Low-Power Microwave-Induction Heating Scheme on the Cross-Linking Process of the Poly(4-vinylphenol) for the Gate Insulator of Pentacene-Based Thin-Film Transistors

    Science.gov (United States)

    Fan, Ching-Lin; Shang, Ming-Chi; Wang, Shea-Jue; Hsia, Mao-Yuan; Lee, Win-Der; Huang, Bohr-Ran

    2017-01-01

    In this study, a proposed Microwave-Induction Heating (MIH) scheme has been systematically studied to acquire suitable MIH parameters including chamber pressure, microwave power and heating time. The proposed MIH means that the thin indium tin oxide (ITO) metal below the Poly(4-vinylphenol) (PVP) film is heated rapidly by microwave irradiation and the heated ITO metal gate can heat the PVP gate insulator, resulting in PVP cross-linking. It is found that the attenuation of the microwave energy decreases with the decreasing chamber pressure. The optimal conditions are a power of 50 W, a heating time of 5 min, and a chamber pressure of 20 mTorr. When suitable MIH parameters were used, the effect of PVP cross-linking and the device performance were similar to those obtained using traditional oven heating, even though the cross-linking time was significantly decreased from 1 h to 5 min. Besides the gate leakage current, the interface trap state density (Nit) was also calculated to describe the interface status between the gate insulator and the active layer. The lowest interface trap state density can be found in the device with the PVP gate insulator cross-linked by using the optimal MIH condition. Therefore, it is believed that the MIH scheme is a good candidate to cross-link the PVP gate insulator for organic thin-film transistor applications as a result of its features of rapid heating (5 min) and low-power microwave-irradiation (50 W). PMID:28773101

  20. Investigation of Rapid Low-Power Microwave-Induction Heating Scheme on the Cross-Linking Process of the Poly(4-vinylphenol for the Gate Insulator of Pentacene-Based Thin-Film Transistors

    Directory of Open Access Journals (Sweden)

    Ching-Lin Fan

    2017-07-01

    Full Text Available In this study, a proposed Microwave-Induction Heating (MIH scheme has been systematically studied to acquire suitable MIH parameters including chamber pressure, microwave power and heating time. The proposed MIH means that the thin indium tin oxide (ITO metal below the Poly(4-vinylphenol (PVP film is heated rapidly by microwave irradiation and the heated ITO metal gate can heat the PVP gate insulator, resulting in PVP cross-linking. It is found that the attenuation of the microwave energy decreases with the decreasing chamber pressure. The optimal conditions are a power of 50 W, a heating time of 5 min, and a chamber pressure of 20 mTorr. When suitable MIH parameters were used, the effect of PVP cross-linking and the device performance were similar to those obtained using traditional oven heating, even though the cross-linking time was significantly decreased from 1 h to 5 min. Besides the gate leakage current, the interface trap state density (Nit was also calculated to describe the interface status between the gate insulator and the active layer. The lowest interface trap state density can be found in the device with the PVP gate insulator cross-linked by using the optimal MIH condition. Therefore, it is believed that the MIH scheme is a good candidate to cross-link the PVP gate insulator for organic thin-film transistor applications as a result of its features of rapid heating (5 min and low-power microwave-irradiation (50 W.

  1. 'BREAKS' Protocol for Breaking Bad News.

    Science.gov (United States)

    Narayanan, Vijayakumar; Bista, Bibek; Koshy, Cheriyan

    2010-05-01

    Information that drastically alters the life world of the patient is termed as bad news. Conveying bad news is a skilled communication, and not at all easy. The amount of truth to be disclosed is subjective. A properly structured and well-orchestrated communication has a positive therapeutic effect. This is a process of negotiation between patient and physician, but physicians often find it difficult due to many reasons. They feel incompetent and are afraid of unleashing a negative reaction from the patient or their relatives. The physician is reminded of his or her own vulnerability to terminal illness, and find themselves powerless over emotional distress. Lack of sufficient training in breaking bad news is a handicap to most physicians and health care workers. Adherence to the principles of client-centered counseling is helpful in attaining this skill. Fundamental insight of the patient is exploited and the bad news is delivered in a structured manner, because the patient is the one who knows what is hurting him most and he is the one who knows how to move forward. Six-step SPIKES protocol is widely used for breaking bad news. In this paper, we put forward another six-step protocol, the BREAKS protocol as a systematic and easy communication strategy for breaking bad news. Development of competence in dealing with difficult situations has positive therapeutic outcome and is a professionally satisfying one.

  2. Gauge symmetry breaking

    International Nuclear Information System (INIS)

    Weinberg, S.

    1976-01-01

    The problem of how gauge symmetries of the weak interactions get broken is discussed. Some reasons why such a heirarchy of gauge symmetry breaking is needed, the reason gauge heirarchies do not seem to arise in theories of a given and related type, and the implications of theories with dynamical symmetry breaking, which can exhibit a gauge hierarchy

  3. Dynamical supersymmetry breaking

    International Nuclear Information System (INIS)

    Affleck, I.

    1985-03-01

    Supersymmetry, and in particular, dynamical supersymmetry breaking, offers the hope of a natural solution of the gauge hierarchy problem in grand unification. I briefly review recent work on dynamical supersymmetry breaking in four-dimensional Higgs theories and its application to grand unified model building

  4. Practicing induction:

    DEFF Research Database (Denmark)

    Sprogøe, Jonas; Rohde, Nicolas

    2009-01-01

    We claim that induction potentially triggers both individual and organizational learning and by drawing on practice-based theory we discuss how the interplay between individual and organization, what we call a generative dance, ignites both kinds of learning.......We claim that induction potentially triggers both individual and organizational learning and by drawing on practice-based theory we discuss how the interplay between individual and organization, what we call a generative dance, ignites both kinds of learning....

  5. Consistency of Trend Break Point Estimator with Underspecified Break Number

    Directory of Open Access Journals (Sweden)

    Jingjing Yang

    2017-01-01

    Full Text Available This paper discusses the consistency of trend break point estimators when the number of breaks is underspecified. The consistency of break point estimators in a simple location model with level shifts has been well documented by researchers under various settings, including extensions such as allowing a time trend in the model. Despite the consistency of break point estimators of level shifts, there are few papers on the consistency of trend shift break point estimators in the presence of an underspecified break number. The simulation study and asymptotic analysis in this paper show that the trend shift break point estimator does not converge to the true break points when the break number is underspecified. In the case of two trend shifts, the inconsistency problem worsens if the magnitudes of the breaks are similar and the breaks are either both positive or both negative. The limiting distribution for the trend break point estimator is developed and closely approximates the finite sample performance.

  6. Supersymmetry breaking from superstrings

    International Nuclear Information System (INIS)

    Gaillard, M.K.; Lawrence Berkeley Lab., CA; California Univ., Berkeley

    1990-01-01

    The gauge hierarchy problem is briefly reviewed and a class of effective field theories obtained from superstrings is described. These are characterized by a clasical symmetry, related to the space-time duality of string theory, that is responsible for the suppression of observable supersymmetry breaking effects. At the quantum level, the symmetry is broken by anomalies that provide the seed of observable supersymmetry breaking, and an acceptably large gauge hierarchy may be generated

  7. Supersymmetry breaking from superstrings

    International Nuclear Information System (INIS)

    Gaillard, M.K.

    1990-05-01

    The gauge hierarchy problem is briefly reviewed and a class of effective field theories obtained from superstrings is described. These are characterized by a classical symmetry, related to the space-time duality of string theory, that is responsible for the suppression of observable supersymmetry breaking effects. At the quantum level, the symmetry is broken by anomalies that provide the seed of observable supersymmetry breaking, and an acceptably large gauge hierarchy may be generated. 26 refs

  8. Determination of As, Cr, Mo, Sb, Se and V in agricultural soil samples by inductively coupled plasma optical emission spectrometry after simple and rapid solvent extraction using choline chloride-oxalic acid deep eutectic solvent.

    Science.gov (United States)

    Matong, Joseph M; Nyaba, Luthando; Nomngongo, Philiswa N

    2017-01-01

    A rapid, simple and green ultrasound-assisted extraction method using deep eutectic solvents (DES) for extraction of As, Cr, Mo, Sb, Se and V in soil samples, has been developed. Choline chloride-oxalic acid based DES was used as a solvent. The target analytes were subsequently quantified using inductively coupled plasma optical emission spectrometer (ICP OES). The parameters that affect the extraction of the target analytes was optimized using standard reference material of San Joaquin soil (SRM 2709a). In the optimization step, a two-level full factorial experimental design was used. The factors under investigation include extraction time, sample mass and acid concentration. Under optimized conditions, limits of detection (LOD) and limits of quantification (LOQ) ranged from 0.009 to 0.1 and 0.03-0.3µgg -1 , respectively. The repeatability (n=20) estimated in terms of relative standard deviation (%RSD) ranged from 0.9% to 3.7%. The accuracy of the proposed method was carried out using SRM 2709a. The obtained and certified/ indicative values were statistically in good agreement at 95% confidence level. The proposed method applied for quantification of As, Cr, Mo, Sb, Se and V in real soil samples. For comparison, the analytes of interest were also determined using a conventional acid digestion method. According to the paired t-test, the analytical results were not significant differences at 95% confidence level. The method was found to be accurate, precise and environmentally friendly. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Induction practice -

    DEFF Research Database (Denmark)

    Rohde, Nicolas; Sprogøe, Jonas

    2007-01-01

    that induction potentially triggers both individual and organizational learning and by drawing on practice-based theory we discuss how the interplay between individual and the organization, what we call agenerative dance, ignites both kinds of learning. We focus on and describe the interplay , ignites both kinds...

  10. Inductive circuit arrangements

    International Nuclear Information System (INIS)

    Mansfield, Peter; Coxon, R.J.

    1987-01-01

    A switched coil arrangement is connected in a bridge configuration of four switches S 1 , S 2 , S 3 and S 4 which are each shunted by diodes D 1 , D 2 , D 3 and D 4 so that current can flow in either direction through a coil L depending on the setting of the switches. A capacitor C is connected across the bridge through a switch S 5 to receive the inductive energy stored in coil L on breaking the current flow path through the coil. The electrostatic energy stored in capacitor C can then be used to supply current through the coil in the reverse direction either immediately or after a time delay. Coil L may be a superconductive coil. Losses in the circuit can be made up by a trickle charge of capacitor C from a separate supply V 2 . The device may be used in nuclear magnetic resonance imaging. (author)

  11. Inductive and electrostatic acceleration in relativistic jet-plasma interactions.

    Science.gov (United States)

    Ng, Johnny S T; Noble, Robert J

    2006-03-24

    We report on the observation of rapid particle acceleration in numerical simulations of relativistic jet-plasma interactions and discuss the underlying mechanisms. The dynamics of a charge-neutral, narrow, electron-positron jet propagating through an unmagnetized electron-ion plasma was investigated using a three-dimensional, electromagnetic, particle-in-cell computer code. The interaction excited magnetic filamentation as well as electrostatic plasma instabilities. In some cases, the longitudinal electric fields generated inductively and electrostatically reached the cold plasma-wave-breaking limit, and the longitudinal momentum of about half the positrons increased by 50% with a maximum gain exceeding a factor of 2 during the simulation period. Particle acceleration via these mechanisms occurred when the criteria for Weibel instability were satisfied.

  12. Strong Electroweak Symmetry Breaking

    CERN Document Server

    Grinstein, Benjamin

    2011-01-01

    Models of spontaneous breaking of electroweak symmetry by a strong interaction do not have fine tuning/hierarchy problem. They are conceptually elegant and use the only mechanism of spontaneous breaking of a gauge symmetry that is known to occur in nature. The simplest model, minimal technicolor with extended technicolor interactions, is appealing because one can calculate by scaling up from QCD. But it is ruled out on many counts: inappropriately low quark and lepton masses (or excessive FCNC), bad electroweak data fits, light scalar and vector states, etc. However, nature may not choose the minimal model and then we are stuck: except possibly through lattice simulations, we are unable to compute and test the models. In the LHC era it therefore makes sense to abandon specific models (of strong EW breaking) and concentrate on generic features that may indicate discovery. The Technicolor Straw Man is not a model but a parametrized search strategy inspired by a remarkable generic feature of walking technicolor,...

  13. Double-strand break induction and DNA damage response after {sup 12}C ion and photon radiation in U87 glioblastoma cells; Doppelstrangbruch-Induktion und DNA-Schadensantwort nach {sup 12}C-Ionen- und Photonenstrahlung in U87 Glioblastomzellen

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Perez, Ramon

    2015-04-22

    Heavy ion radiation has greater biological effectiveness than the same physical dose of photon radiation. In this work the underlying reasons in the DNA damage response were analyzed in U87 glioblastoma cells. DNA double-strand breaks (DSBs) are the decicive lesions for the effectiveness of ionizing radiation. Their induction and repair was measured in the context of the cell cycle based on the DSB marker γH2AX (the phosphorylated form of the histone variant H2AX). Further, radiation-specific differences in choice of the DSB repair pathway was analyzed, as well as the consequences of repair failure. The results showed that in contrast to photons, {sup 12}C ion radiation produces more severe DSBs that are repaired delayed and with slower kinetics. Accordingly, stronger and longer lasting cell cycle delays, predominantly at the G2/M border, and a higher rate of apoptosis was detected for {sup 12}C ion radiation. Autophagy, an alternative mechanism of programmed cell death, was not relevant for neither of the two types of radiation. The effect of {sup 12}C ion radiation was less dependent on the cell cycle stage than for photon radiation. This became particularly evident in the DSB repair velocities during S- and G2-phase. After {sup 12}C ion radiation, cells were more dependent on homologous recombination repair (HRR) compared to photon radiation. The reason therefore that in contrast to photons, {sup 12}C ion radiation induced graver DSBs that were repaired slower and more dependent on HRR, was most probably enhanced clustering of DSBs due to the higher ionization density of {sup 12}C ion radiation. Microscopic inspection of immunofluorently stained γH2AX revealed that {sup 12}C ion radiation induced bigger DSB repair foci containing more γH2AX molecules (higher fluorescence intensity), although their initial number was smaller. Besides the foci, a weaker pan-nuclear γH2AX staining was observed that increased in a dose-dependent manner and was more pronounced

  14. Induction Brazing

    DEFF Research Database (Denmark)

    Henningsen, Poul

    , or if the hottest area is located outside the joint interface, a number of defects may appear: the braze metal may flow away from the joint, the flux may burn off, poor binding of the braze metal may appear or the braze metal may be overheated. Joint geometry as well as electro-magnetic properties of the work piece...... presents a combined numerical and experimental method for determination of appropriate/optimiged coil geometry and position in induction brazing tube-to-plate joints of different ratios between tube and plate thickness and different combinations of the materials stainless steel, brass and copper....... The method has proven to give successful results in brazing tube-plate joints of copper-brass, copper-stainless steel, stainless steel-brass, and stainless steel-stainless steel. A new design of an adjustable flux concentrator for induction heating tube-to-plate joints is proposed and tested on a variety...

  15. Rapid determination of {sup 135}Cs and precise {sup 135}Cs/{sup 137}Cs atomic ratio in environmental samples by single-column chromatography coupled to triple-quadrupole inductively coupled plasma-mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Guosheng [Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564 (Japan); Division of Nuclear Technology and Applications, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Beijing Engineering Research Center of Radiographic Techniques and Equipment, Beijing 100049 (China); Tazoe, Hirofumi [Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564 (Japan); Yamada, Masatoshi, E-mail: myamada@hirosaki-u.ac.jp [Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564 (Japan)

    2016-02-18

    For source identification, measurement of {sup 135}Cs/{sup 137}Cs atomic ratio not only provides information apart from the detection of {sup 134}Cs and {sup 137}Cs, but it can also overcome the application limit that measurement of the {sup 134}Cs/{sup 137}Cs ratio has due to the short half-life of {sup 134}Cs (2.06 y). With the recent advancement of ICP-MS, it is necessary to improve the corresponding separation method for rapid and precise {sup 135}Cs/{sup 137}Cs atomic ratio analysis. A novel separation and purification technique was developed for the new generation of triple-quadrupole inductively coupled plasma-mass spectrometry (ICP-MS/MS). The simple chemical separation, incorporating ammonium molybdophosphate selective adsorption of Cs and subsequent single cation-exchange chromatography, removes the majority of isobaric and polyatomic interference elements. Subsequently, the ICP-MS/MS removes residual interference elements and eliminates the peak tailing effect of stable {sup 133}Cs, at m/z 134, 135, and 137. The developed analytical method was successfully applied to measure {sup 135}Cs/{sup 137}Cs atomic ratios and {sup 135}Cs activities in environmental samples (soil and sediment) for radiocesium source identification. - Highlights: • A simple {sup 135}Cs/{sup 137}Cs analytical method was developed. • The separation procedure was based on AMP adsorption and one column chromatography. • {sup 135}Cs/{sup 137}Cs was measured by ICP-MS/MS. • Decontamination factors for Ba, Mo, Sb, and Sn were improved. • {sup 135}Cs/{sup 137}Cs atomic ratios of 0.341–0.351 were found in Japanese soil samples.

  16. Breaking the silence

    DEFF Research Database (Denmark)

    Konradsen, Hanne; Kirkevold, Marit; McCallin, Antoinette

    2012-01-01

    and individual interviews were analyzed using the grounded theory method. The findings revealed that the main concern of the patients was feeling isolated, which was resolved using a process of interactional integration. Interactional integration begins by breaking the silence to enable the progression from...

  17. Violent breaking wave impacts

    DEFF Research Database (Denmark)

    Bredmose, Henrik; Peregrine, D.H.; Bullock, G.N.

    2009-01-01

    When an ocean wave breaks against a steep-fronted breakwater, sea wall or a similar marine structure, its impact on the structure can be very violent. This paper describes the theoretical studies that, together with field and laboratory investigations, have been carried out in order to gain a bet...

  18. Routinizing Breaking News

    DEFF Research Database (Denmark)

    Hartley, Jannie Møller

    2011-01-01

    This chapter revisits seminal theoretical categorizations of news proposed three decades earlier by US sociologist Gaye Tuchman. By exploring the definition of ”breaking news” in the contemporary online newsrooms of three Danish news organisations, the author offers us a long overdue re-theorizat......-theorization of journalistic practice in the online context and helpfully explores well-evidenced limitations to online news production, such as the relationship between original reporting and the use of ”shovelware.”......This chapter revisits seminal theoretical categorizations of news proposed three decades earlier by US sociologist Gaye Tuchman. By exploring the definition of ”breaking news” in the contemporary online newsrooms of three Danish news organisations, the author offers us a long overdue re...

  19. Breaking News as Radicalisation

    DEFF Research Database (Denmark)

    Hartley, Jannie Møller

    The aim of the paper is to make explicit how the different categories are applied in the online newsroom and thus how new categories can be seen as positioning strategies in the form of radicalisations of already existing categories. Thus field theory provides us with tools to analyse how online...... journalists are using the categorisations to create hierarchies within the journalistic field in order to position themselves as specialists in what Tuchman has called developing news, aiming and striving for what today is know as breaking news and the “exclusive scoop,” as the trademark of online journalism...... in a media environment where immediacy rules (Domingo 2008a). Following this research the primary focus of this paper is the category breaking news and Tuchmans developing news, but as they are all connected the analysis will also draw upon the other categories in Tuchmans typology. The theoretical framework...

  20. Influence of night-breaks on flowering and phytohormones content in Hyoscyamus niger L.

    OpenAIRE

    Jan Kopcewicz; Gabriela Centkowska

    2014-01-01

    Night-breaks caused both stimulated shoot growth and caused formation of flowers as well as a general increase in the content of phytohormones in leaves of the long-day plant Hyoscyamus niger L. At the time of flower formation in night-break treated plants, new gibberellin-like substances also appear. The results show that night-breaks cause similar changes in the phytohormones content as a long inductive photoperiod. It may be assumed that independently of the way of induction, the generativ...

  1. Predicting appointment breaking.

    Science.gov (United States)

    Bean, A G; Talaga, J

    1995-01-01

    The goal of physician referral services is to schedule appointments, but if too many patients fail to show up, the value of the service will be compromised. The authors found that appointment breaking can be predicted by the number of days to the scheduled appointment, the doctor's specialty, and the patient's age and gender. They also offer specific suggestions for modifying the marketing mix to reduce the incidence of no-shows.

  2. Single sector supersymmetry breaking

    International Nuclear Information System (INIS)

    Luty, Markus A.; Terning, John

    1999-01-01

    We review recent work on realistic models that break supersymmetry dynamically and give rise to composite quarks and leptons, all in a single sector. These models have a completely natural suppression of flavor-changing neutral currents, and the hierarchy of Yukawa couplings is explained by the dimensionality of composite states. The generic signatures are unification of scalar masses with different quantum numbers at the compositeness scale, and lighter gaugino, Higgsino, and third-generation sfermion masses

  3. Dual descriptions of supersymmetry breaking

    International Nuclear Information System (INIS)

    Intrilligator, K.; Thomas, S.

    1996-08-01

    Dynamical supersymmetry breaking is considered in models which admit descriptions in terms of electric, confined, or magnetic degrees of freedom in various limits. In this way, a variety of seemingly different theories which break supersymmetry are actually interrelated by confinement or duality. Specific examples are given in which there are two dual descriptions of the supersymmetry breaking ground state

  4. The Beam Break-Up Numerical Simulator

    International Nuclear Information System (INIS)

    Travish, G.A.

    1989-11-01

    Beam Break-Up (BBU) is a severe constraint in accelerator design, limiting beam current and quality. The control of BBU has become the focus of much research in the design of the next generation collider, recirculating and linear induction accelerators and advanced accelerators. Determining the effect on BBU of modifications to cavities, the focusing elements or the beam is frequently beyond the ability of current analytic models. A computer code was written to address this problem. The Beam Break-Up Numerical Simulator (BBUNS) was designed to numerically solve for beam break-up (BBU) due to an arbitrary transverse wakefield. BBUNS was developed to be as user friendly as possible on the Cray computer series. The user is able to control all aspects of input and output by using a single command file. In addition, the wakefield is specified by the user and read in as a table. The program can model energy variations along and within the beam, focusing magnetic field profiles can be specified, and the graphical output can be tailored. In this note we discuss BBUNS, its structure and application. Included are detailed instructions, examples and a sample session of BBUNS. This program is available for distribution. 50 refs., 18 figs., 5 tabs

  5. Regulation of ATM induction

    International Nuclear Information System (INIS)

    Clarke, R.A.; Fang, Z.M.; Kearsley, J.H.; Lee, C.S.; Sarris, M.; De Murrell, D.

    2000-01-01

    Full text: ATM, the tumour suppressor protein mutated in ataxia-telangiectasia, is of pivotal importance in controlling the cells primary response to ionising radiation (IR) induced DNA damage. Mutations in ATM which reduce the level of the ATM protein and/or compromise ATM functions are known to give rise to radiosensitivity and defective cell cycle checkpoint control. In response to DNA damage ATM kinase is rapidly activated and initiates downstream signalling to cell cycle control molecules including p53. To investigate additional mechanisms of ATM control we have employed ATM antisense expression in cultured cells, western analyses and immunohistochemistry in situ. We report that ATM can be up-regulated up to 10-fold following exposure to low levels of ionising radiation. ATM radiation-induction was radiation dose dependent while the rapidity of the response indicates a post translational pathway. The concurrent time frames for the radiation-induction of ATM levels and the activation of ATM kinase activity appear to be complimentary in boosting ATM's protective response to IR induced DNA damage, especially in ATM 'low expressing' systems. We also provide the first report of ATM misregulation in 2 cancer patients, indicating that ATM is not only radio-protective but has possible implications in cancer, particularly breast cancer. These results have particular importance in defining the regulation of the ATM protein as an: adaptive radio-response; radio-prognostic market in tumours and normal tissue, and breast cancer marker

  6. BOOK REVIEW: Symmetry Breaking

    Science.gov (United States)

    Ryder, L. H.

    2005-11-01

    One of the most fruitful and enduring advances in theoretical physics during the last half century has been the development of the role played by symmetries. One needs only to consider SU(3) and the classification of elementary particles, the Yang Mills enlargement of Maxwell's electrodynamics to the symmetry group SU(2), and indeed the tremendous activity surrounding the discovery of parity violation in the weak interactions in the late 1950s. This last example is one of a broken symmetry, though the symmetry in question is a discrete one. It was clear to Gell-Mann, who first clarified the role of SU(3) in particle physics, that this symmetry was not exact. If it had been, it would have been much easier to discover; for example, the proton, neutron, Σ, Λ and Ξ particles would all have had the same mass. For many years the SU(3) symmetry breaking was assigned a mathematical form, but the importance of this formulation fell away when the quark model began to be taken seriously; the reason the SU(3) symmetry was not exact was simply that the (three, in those days) quarks had different masses. At the same time, and in a different context, symmetry breaking of a different type was being investigated. This went by the name of `spontaneous symmetry breaking' and its characteristic was that the ground state of a given system was not invariant under the symmetry transformation, though the interactions (the Hamiltonian, in effect) was. A classic example is ferromagnetism. In a ferromagnet the atomic spins are aligned in one direction only—this is the ground state of the system. It is clearly not invariant under a rotation, for that would change the ground state into a (similar but) different one, with the spins aligned in a different direction; this is the phenomenon of a degenerate vacuum. The contribution of the spin interaction, s1.s2, to the Hamiltonian, however, is actually invariant under rotations. As Coleman remarked, a little man living in a ferromagnet would

  7. Prediction of LOCA Break Size Using CFNN

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Geon Pil; Yoo, Kwae Hwan; Back, Ju Hyun; Kim, Dong Yeong; Na, Man Gyun [Chosun University Gwangju (Korea, Republic of)

    2016-05-15

    The NPPs have the emergency core cooling system (ECCS) such as a safety injection system. The ECCS may not function properly in case of the small break size due to a slight change of pressure in the pipe. If the coolant is not supplied by ECCS, the reactor core will melt. Therefore, the meltdown of reactor core have to be prevented by appropriate accident management through the prediction of LOCA break size in advance. This study presents the prediction of LOCA break size using cascaded fuzzy neural network (CFNN). The CFNN model repeatedly applies FNN modules that are serially connected. The CFNN model is a data-based method that requires data for its development and verification. The data were obtained by numerically simulating severe accident scenarios of the optimized power reactor (OPR1000) using MAAP code, because real severe accident data cannot be obtained from actual NPP accidents. The CFNN model has been designed to rapidly predict the LOCA break size in LOCA situations. The CFNN model was trained by using the training data set and checked by using test data set. These data sets were obtained using MAAP code for OPR1000 reactor. The performance results of the CFNN model show that the RMS error decreases as the stage number of the CFNN model increases. In addition, the performance result of the CFNN model presents that the RMS error level is below 4%.

  8. Inertial Symmetry Breaking

    Energy Technology Data Exchange (ETDEWEB)

    Hill, Christopher T.

    2018-03-19

    We review and expand upon recent work demonstrating that Weyl invariant theories can be broken "inertially," which does not depend upon a potential. This can be understood in a general way by the "current algebra" of these theories, independently of specific Lagrangians. Maintaining the exact Weyl invariance in a renormalized quantum theory can be accomplished by renormalization conditions that refer back to the VEV's of fields in the action. We illustrate the computation of a Weyl invariant Coleman-Weinberg potential that breaks a U(1) symmetry together,with scale invariance.

  9. Break the Pattern!

    DEFF Research Database (Denmark)

    Hasse, Cathrine; Trentemøller, Stine

    Break the Pattern! A critical enquiry into three scientific workplace cultures: Hercules, Caretakers and Worker Bees is the third publication of the international three year long project "Understanding Puzzles in the Gendered European Map" (UPGEM). By contrasting empirical findings from academic ...... (physics in culture) and discuss how physics as and in culture influence the perception of science, of work and family life, of the interplay between religion and science as well as how physics as culture can either hinder or promote the career of female scientists....

  10. Breaking the Waves

    DEFF Research Database (Denmark)

    Christensen, Poul Rind; Kirketerp, Anne

    2006-01-01

    The paper shortly reveals the history of a small school - the KaosPilots - dedicated to educate young people to carriers as entrepreneurs. In this contribution we want to explore how the KaosPilots managed to break the waves of institutionalised concepts and practices of teaching entrepreneurship....... Following the so-called 'Dogma' concept developed by Danish filmmakers, this contribution aim to explore the key elements making up the recipes guiding the entrepreneurship training program exercised by the school. Key factors forming a community of learning practice are outlined as well as the critical...... pedagogical elements on which the education in entrepreneurship rests....

  11. Coreless Concept for High Gradient Induction Cell

    International Nuclear Information System (INIS)

    Krasnykh, Anatoly

    2008-01-01

    An induction linac cell for a high gradient is discussed. The proposed solid state coreless approach for the induction linac topology (SLIM(reg s ign)) is based on nanosecond mode operation. This mode may have an acceleration gradient comparable with gradients of rf- accelerator structures. The discussed induction system has the high electric efficiency. The key elements are a solid state semiconductor switch and a high electric density dielectric with a thin section length. The energy in the induction system is storied in the magnetic field. The nanosecond current break-up produces the high voltage. The induced voltage is used for acceleration. This manner of an operation allows the use of low voltage elements in the booster part and achieves a high accelerating gradient. The proposed topology was tested in POP (proof of principle) experiments

  12. Repair on the go: E. coli maintains a high proliferation rate while repairing a chronic DNA double-strand break.

    Directory of Open Access Journals (Sweden)

    Elise Darmon

    Full Text Available DNA damage checkpoints exist to promote cell survival and the faithful inheritance of genetic information. It is thought that one function of such checkpoints is to ensure that cell division does not occur before DNA damage is repaired. However, in unicellular organisms, rapid cell multiplication confers a powerful selective advantage, leading to a dilemma. Is the activation of a DNA damage checkpoint compatible with rapid cell multiplication? By uncoupling the initiation of DNA replication from cell division, the Escherichia coli cell cycle offers a solution to this dilemma. Here, we show that a DNA double-strand break, which occurs once per replication cycle, induces the SOS response. This SOS induction is needed for cell survival due to a requirement for an elevated level of expression of the RecA protein. Cell division is delayed, leading to an increase in average cell length but with no detectable consequence on mutagenesis and little effect on growth rate and viability. The increase in cell length caused by chronic DNA double-strand break repair comprises three components: two types of increase in the unit cell size, one independent of SfiA and SlmA, the other dependent of the presence of SfiA and the absence of SlmA, and a filamentation component that is dependent on the presence of either SfiA or SlmA. These results imply that chronic checkpoint induction in E. coli is compatible with rapid cell multiplication. Therefore, under conditions of chronic low-level DNA damage, the SOS checkpoint operates seamlessly in a cell cycle where the initiation of DNA replication is uncoupled from cell division.

  13. More dynamical supersymmetry breaking

    International Nuclear Information System (INIS)

    Csaki, C.; Randall, L.; Skiba, W.

    1996-01-01

    In this paper we introduce a new class of theories which dynamically break supersymmetry based on the gauge group SU(n) x SU(3) x U(1) for even n. These theories are interesting in that no dynamical superpotential is generated in the absence of perturbations. For the example SU(4) x SU(3) x U(1) we explicitly demonstrate that all flat directions can be lifted through a renormalizable superpotential and that supersymmetry is dynamically broken. We derive the exact superpotential for this theory, which exhibits new and interesting dynamical phenomena. For example, modifications to classical constraints can be field dependent. We also consider the generalization to SU(n) x SU(3) x U(1) models (with even n>4). We present a renormalizable superpotential which lifts all flat directions. Because SU(3) is not confining in the absence of perturbations, the analysis of supersymmetry breaking is very different in these theories from the n=4 example. When the SU(n) gauge group confines, the Yukawa couplings drive the SU(3) theory into a regime with a dynamically generated superpotential. By considering a simplified version of these theories we argue that supersymmetry is probably broken. (orig.)

  14. Bootstrap Dynamical Symmetry Breaking

    Directory of Open Access Journals (Sweden)

    Wei-Shu Hou

    2013-01-01

    Full Text Available Despite the emergence of a 125 GeV Higgs-like particle at the LHC, we explore the possibility of dynamical electroweak symmetry breaking by strong Yukawa coupling of very heavy new chiral quarks Q . Taking the 125 GeV object to be a dilaton with suppressed couplings, we note that the Goldstone bosons G exist as longitudinal modes V L of the weak bosons and would couple to Q with Yukawa coupling λ Q . With m Q ≳ 700  GeV from LHC, the strong λ Q ≳ 4 could lead to deeply bound Q Q ¯ states. We postulate that the leading “collapsed state,” the color-singlet (heavy isotriplet, pseudoscalar Q Q ¯ meson π 1 , is G itself, and a gap equation without Higgs is constructed. Dynamical symmetry breaking is affected via strong λ Q , generating m Q while self-consistently justifying treating G as massless in the loop, hence, “bootstrap,” Solving such a gap equation, we find that m Q should be several TeV, or λ Q ≳ 4 π , and would become much heavier if there is a light Higgs boson. For such heavy chiral quarks, we find analogy with the π − N system, by which we conjecture the possible annihilation phenomena of Q Q ¯ → n V L with high multiplicity, the search of which might be aided by Yukawa-bound Q Q ¯ resonances.

  15. Breaking of ocean surface waves

    International Nuclear Information System (INIS)

    Babanin, A.V.

    2009-01-01

    Wind-generated waves are the most prominent feature of the ocean surface, and so are breaking waves manifested by the appearance of sporadic whitecaps. Such breaking represents one of the most interesting and most challenging problems for both fluid mechanics and physical oceanography. It is an intermittent random process, very fast by comparison with other processes in the wave breaking on the water surface is not continuous, but its role in maintaining the energy balance within the continuous wind-wave field is critical. Ocean wave breaking also plays the primary role in the air-sea exchange of momentum, mass and heat, and it is of significant importance for ocean remote sensing, coastal and maritime engineering, navigation and other practical applications. Understanding the wave breaking its occurrence, the breaking rates and even ability to describe its onset has been hindered for decades by the strong non-linearity of the process, together with its irregular and ferocious nature. Recently, this knowledge has significantly advanced, and the review paper is an attempt to summarise the facts into a consistent, albeit still incomplete picture of the phenomenon. In the paper, variety of definitions related to the were breaking are discussed and formulated and methods for breaking detection and measurements are examined. Most of attention is dedicated to the research of wave breaking probability and severity. Experimental, observational, numerical and statistical approaches and their outcomes are reviewed. Present state of the wave-breaking research and knowledge is analysed and main outstanding problems are outlined (Authors)

  16. Small break loss of coolant accidents: Bottom and side break

    International Nuclear Information System (INIS)

    Hardy, P.G.; Richter, H.J.

    1987-01-01

    A LOCA can be caused, e.g. by a small break in the primary cooling system. The rate of fluid escaping through such a break will define the time until the core will be uncovered. Therefore the prediction of fluid loss and pressure transient is of major importance to plan for timely action in response to such an event. Stratification of the two phases might be present upstream of the break, thus, the location of the break relative to the vapor-liquid interface and the overall upstream fluid conditions are relevant for the calculation of fluid loss. Experimental results and analyses are presented here for small breaks at the bottom or at the side of a small pressure vessel. It was found that in such a case the onset of the so-called ''vapor pull through'' is important but swelling at sufficient depressurization rates of the liquid due to flashing is also of significance. It was also discovered that in the bottom break the flow rate is strongly dependent on the break entrance quality of the vapour-liquid mixture. The side break can be treated similarly to the bottom break if the interface level is above the break. The analyses developed on the basis of experimental observations showed reasonable agreement of predicted and measured pressure transients. It was possible to calculate the changing interface level and mixture void fraction history in a way compatible with the behavior observed during the experiments. Even though the experiments were performed at low pressures, this work should help to get a better understanding of physical phenomena occurring in a full scale small break LOCA. (orig./HP)

  17. 5 KV low-induction capactitor battery

    International Nuclear Information System (INIS)

    Babalin, A.I.; Burtsev, V.A.; Emel'yanov, A.I.; Kunaev, G.T.; Ovsyannikov, V.A.; Zhmodikov, B.S.

    1981-01-01

    A 1.2 MJ capacitor battery is developed and constructed for creating strong magnetic fields for thermonuclear facilities, pumping of laser active media. The capacitor battery is assembled of 512 IMU5-150 and 128 IS5-200 capacitors. The design is based on division of the capacitor battery in 40 sections. The energy commutation is performed by air spark gaps of the trigatron type with 24 to 60 nH inductance. Electromagnetic switches are made on the base of the EP 41V-33 relay. A low-induction generator is developed for spark gap ignition. The capacitor sections, each of them comprising 16 capacitors, and loadings are switched-in either by means of cables or flat lines. Accidents were not observed during operation of 20 sections of the capacitor battery (capacitors break-down, break of polyethylene isolation, deformation of tyre-wires) [ru

  18. Electroweak breaking in supersymmetric models

    CERN Document Server

    Ibáñez, L E

    1992-01-01

    We discuss the mechanism for electroweak symmetry breaking in supersymmetric versions of the standard model. After briefly reviewing the possible sources of supersymmetry breaking, we show how the required pattern of symmetry breaking can automatically result from the structure of quantum corrections in the theory. We demonstrate that this radiative breaking mechanism works well for a heavy top quark and can be combined in unified versions of the theory with excellent predictions for the running couplings of the model. (To be published in ``Perspectives in Higgs Physics'', G. Kane editor.)

  19. Single-strand breaks induced in Bacillus subtilis DNA by ultraviolet light: action spectrum and properties

    International Nuclear Information System (INIS)

    Peak, M.J.; Peak, J.G.

    1982-01-01

    The induction of single-strand breaks (alkali-labile bonds plus frank breaks) in the DNA of Bacillus subtilis irradiated in vivo by monochromatic UV light at wavelengths from 254 to 434nm was measured. The spectrum consists of a major far-UV (below 320nm) component and a minor near-UV shoulder. A mutant deficient in DNA polymerase I accumulates breaks caused by near-UV (above 320nm) wavelengths faster than the wild-type strain proficient in polymerase I. Measurable breaks in extracted DNA are induced at a higher frequency than those induced in vivo. Anoxia, glycerol, and diazobicyclo (2.2.2.) octane inhibit break formation in extracted DNA. Alkali-labile bonds induced by 365-nm UV radiation are largely (78%) covalent bond chain breaks, the remainder consists of true alkali-labile bonds, probably apurinic and apyrimidinic sites. (author)

  20. Correlations of DNA strand breaks and their repair with cell survival following acute exposure to mercury(II) and X-rays

    International Nuclear Information System (INIS)

    Cantoni, O.; Costa, M.

    1983-01-01

    Alkaline elution analysis demonstrates that both HgCl 2 and X-rays result in a rapid induction of DNA single-strand breaks at acutely cytotoxic doses (HgCl 2 , 25-100 microM for 60 min; X-rays, 150-600 rads) in cultured Chinese hamster ovary cells. Cytotoxicity, as measured by cell-plating efficiency, correlates linearly with the level of DNA breakage induced by both agents (HgCl 2 , r . 0.97; X-rays, r . 0.99), although a substantial difference in axis intercepts of the two linear regression lines indicates that a higher level of DNA damage was required by X-rays as compared with HgCl 2 to produce an equivalent level of cell killing. DNA damage induced by X-rays was rapidly repaired such that within 1 hr following treatment the elution rate of DNA from treated cells resembled that obtained in untreated cultures. In contrast, DNA damage after Hg 2+ insult was not repaired, and further damage was evident following a similar 1-hr recovery period. Addition of noncytotoxic, non-DNA-damaging concentrations of HgCl 2 (10 microM) to cells 15-45 min following treatment with X-rays greatly inhibited the repair of the DNA strand breaks. Thus, although both HgCl 2 and X-rays induce rapid and striking single-strand breaks in the DNA, persistence of Hg 2+ in the cell can inhibit the repair of these breaks. The inhibition of DNA repair by HgCl 2 may explain why this agent is not severely mutagenic or carcinogenic despite its ability to induce an X-ray-like DNA damage and why a lower level of mercury-induced DNA damage, compared with that induced by X-rays, was required to produce an equivalent level of cell death

  1. Attributing Changing Rates of Temperature Record Breaking to Anthropogenic Influences

    Science.gov (United States)

    King, Andrew D.

    2017-11-01

    Record-breaking temperatures attract attention from the media, so understanding how and why the rate of record breaking is changing may be useful in communicating the effects of climate change. A simple methodology designed for estimating the anthropogenic influence on rates of record breaking in a given time series is proposed here. The frequency of hot and cold record-breaking temperature occurrences is shown to be changing due to the anthropogenic influence on the climate. Using ensembles of model simulations with and without human-induced forcings, it is demonstrated that the effect of climate change on global record-breaking temperatures can be detected as far back as the 1930s. On local scales, a climate change signal is detected more recently at most locations. The anthropogenic influence on the increased occurrence of hot record-breaking temperatures is clearer than it is for the decreased occurrence of cold records. The approach proposed here could be applied in rapid attribution studies of record extremes to quantify the influence of climate change on the rate of record breaking in addition to the climate anomaly being studied. This application is demonstrated for the global temperature record of 2016 and the Central England temperature record in 2014.

  2. R-parity breaking phenomenology

    International Nuclear Information System (INIS)

    Vissani, F.

    1996-02-01

    We review various features of the R-parity breaking phenomenology, with particular attention to the low energy observables, and to the patterns of the R-parity breaking interactions that arise in Grand Unified models. (author). 22 refs, 1 fig., 3 tabs

  3. Inflation from supersymmetry breaking

    Energy Technology Data Exchange (ETDEWEB)

    Antoniadis, I. [UMR CNRS 7589 Sorbonne Universites, UPMC Paris 6, LPTHE, Paris (France); University of Bern, Albert Einstein Center, Institute for Theoretical Physics, Bern (Switzerland); Chatrabhuti, A.; Isono, H.; Knoops, R. [Chulalongkorn University, Department of Physics, Faculty of Science, Pathumwan, Bangkok (Thailand)

    2017-11-15

    We explore the possibility that inflation is driven by supersymmetry breaking with the superpartner of the goldstino (sgoldstino) playing the role of the inflaton. Moreover, we impose an R-symmetry that allows one to satisfy easily the slow-roll conditions, avoiding the so-called η-problem, and leads to two different classes of small-field inflation models; they are characterised by an inflationary plateau around the maximum of the scalar potential, where R-symmetry is either restored or spontaneously broken, with the inflaton rolling down to a minimum describing the present phase of our Universe. To avoid the Goldstone boson and be left with a single (real) scalar field (the inflaton), R-symmetry is gauged with the corresponding gauge boson becoming massive. This framework generalises a model studied recently by the present authors, with the inflaton identified by the string dilaton and R-symmetry together with supersymmetry restored at weak coupling, at infinity of the dilaton potential. The presence of the D-term allows a tuning of the vacuum energy at the minimum. The proposed models agree with cosmological observations and predict a tensor-to-scalar ratio of primordial perturbations 10{sup -9}

  4. Symmetry breaking by bifundamentals

    Science.gov (United States)

    Schellekens, A. N.

    2018-03-01

    We derive all possible symmetry breaking patterns for all possible Higgs fields that can occur in intersecting brane models: bifundamentals and rank-2 tensors. This is a field-theoretic problem that was already partially solved in 1973 by Ling-Fong Li [1]. In that paper the solution was given for rank-2 tensors of orthogonal and unitary group, and U (N )×U (M ) and O (N )×O (M ) bifundamentals. We extend this first of all to symplectic groups. When formulated correctly, this turns out to be straightforward generalization of the previous results from real and complex numbers to quaternions. The extension to mixed bifundamentals is more challenging and interesting. The scalar potential has up to six real parameters. Its minima or saddle points are described by block-diagonal matrices built out of K blocks of size p ×q . Here p =q =1 for the solutions of Ling-Fong Li, and the number of possibilities for p ×q is equal to the number of real parameters in the potential, minus 1. The maximum block size is p ×q =2 ×4 . Different blocks cannot be combined, and the true minimum occurs for one choice of basic block, and for either K =1 or K maximal, depending on the parameter values.

  5. Symmetry and symmetry breaking

    International Nuclear Information System (INIS)

    Balian, R.; Lambert, D.; Brack, A.; Lachieze-Rey, M.; Emery, E.; Cohen-Tannoudji, G.; Sacquin, Y.

    1999-01-01

    The symmetry concept is a powerful tool for our understanding of the world. It allows a reduction of the volume of information needed to apprehend a subject thoroughly. Moreover this concept does not belong to a particular field, it is involved in the exact sciences but also in artistic matters. Living beings are characterized by a particular asymmetry: the chiral asymmetry. Although this asymmetry is visible in whole organisms, it seems it comes from some molecules that life always produce in one chirality. The weak interaction presents also the chiral asymmetry. The mass of particles comes from the breaking of a fundamental symmetry and the void could be defined as the medium showing as many symmetries as possible. The texts put together in this book show to a great extent how symmetry goes far beyond purely geometrical considerations. Different aspects of symmetry ideas are considered in the following fields: the states of matter, mathematics, biology, the laws of Nature, quantum physics, the universe, and the art of music. (A.C.)

  6. Rapid improvement teams.

    Science.gov (United States)

    Alemi, F; Moore, S; Headrick, L; Neuhauser, D; Hekelman, F; Kizys, N

    1998-03-01

    Suggestions, most of which are supported by empirical studies, are provided on how total quality management (TQM) teams can be used to bring about faster organizationwide improvements. Ideas are offered on how to identify the right problem, have rapid meetings, plan rapidly, collect data rapidly, and make rapid whole-system changes. Suggestions for identifying the right problem include (1) postpone benchmarking when problems are obvious, (2) define the problem in terms of customer experience so as not to blame employees nor embed a solution in the problem statement, (3) communicate with the rest of the organization from the start, (4) state the problem from different perspectives, and (5) break large problems into smaller units. Suggestions for having rapid meetings include (1) choose a nonparticipating facilitator to expedite meetings, (2) meet with each team member before the team meeting, (3) postpone evaluation of ideas, and (4) rethink conclusions of a meeting before acting on them. Suggestions for rapid planning include reducing time spent on flowcharting by focusing on the future, not the present. Suggestions for rapid data collection include (1) sample patients for surveys, (2) rely on numerical estimates by process owners, and (3) plan for rapid data collection. Suggestions for rapid organizationwide implementation include (1) change membership on cross-functional teams, (2) get outside perspectives, (3) use unfolding storyboards, and (4) go beyond self-interest to motivate lasting change in the organization. Additional empirical investigations of time saved as a consequence of the strategies provided are needed. If organizations solve their problems rapidly, fewer unresolved problems may remain.

  7. Making and Breaking Clouds

    Science.gov (United States)

    Kohler, Susanna

    2017-10-01

    Molecular clouds which youre likely familiar with from stunning popular astronomy imagery lead complicated, tumultuous lives. A recent study has now found that these features must be rapidly built and destroyed.Star-Forming CollapseA Hubble view of a molecular cloud, roughly two light-years long, that has broken off of the Carina Nebula. [NASA/ESA, N. Smith (University of California, Berkeley)/The Hubble Heritage Team (STScI/AURA)]Molecular gas can be found throughout our galaxy in the form of eminently photogenic clouds (as featured throughout this post). Dense, cold molecular gas makes up more than 20% of the Milky Ways total gas mass, and gravitational instabilities within these clouds lead them to collapse under their own weight, resulting in the formation of our galaxys stars.How does this collapse occur? The simplest explanation is that the clouds simply collapse in free fall, with no source of support to counter their contraction. But if all the molecular gas we observe collapsed on free-fall timescales, star formation in our galaxy would churn a rate thats at least an order of magnitude higher than the observed 12 solar masses per year in the Milky Way.Destruction by FeedbackAstronomers have theorized that there may be some mechanism that supports these clouds against gravity, slowing their collapse. But both theoretical studies and observations of the clouds have ruled out most of these potential mechanisms, and mounting evidence supports the original interpretation that molecular clouds are simply gravitationally collapsing.A sub-mm image from ESOs APEX telescope of part of the Taurus molecular cloud, roughly ten light-years long, superimposed on a visible-light image of the region. [ESO/APEX (MPIfR/ESO/OSO)/A. Hacar et al./Digitized Sky Survey 2. Acknowledgment: Davide De Martin]If this is indeed the case, then one explanation for our low observed star formation rate could be that molecular clouds are rapidly destroyed by feedback from the very stars

  8. Supersymmetry breaking with extra dimensions

    International Nuclear Information System (INIS)

    Zwirner, Fabio

    2004-01-01

    This talk reviews some aspects of supersymmetry breaking in the presence of extra dimensions. The first part is a general introduction, recalling the motivations for supersymmetry and extra dimensions, as well as some unsolved problems of four-dimensional models of supersymmetry breaking. The central part is a more focused introduction to a mechanism for (super)symmetry breaking, proposed first by Scherk and Schwarz, where extra dimensions play a crucial role. The last part is devoted to the description of some recent results and of some open problems. (author)

  9. Stochastic mechanism of symmetry breaking

    International Nuclear Information System (INIS)

    Baseyan, H.Z.

    1983-01-01

    A new symmetry breaking mechanism conditioned by presence of random fields in vacuum is proposed. Massive Yang-Mills fields finally arise, that may be interpreted as ''macroscopic'' manifestation of the ''microscopic'' Yang-Mills massless theory

  10. Dynamic breaking of a single gold bond

    DEFF Research Database (Denmark)

    Pobelov, Ilya V.; Lauritzen, Kasper Primdal; Yoshida, Koji

    2017-01-01

    While one might assume that the force to break a chemical bond gives a measure of the bond strength, this intuition is misleading. If the force is loaded slowly, thermal fluctuations may break the bond before it is maximally stretched, and the breaking force will be less than the bond can sustain...... of a single Au-Au bond and show that the breaking force is dependent on the loading rate. We probe the temperature and structural dependencies of breaking and suggest that the paradox can be explained by fast breaking of atomic wires and slow breaking of point contacts giving very similar breaking forces....

  11. Single-strand breaks in supercoiled DNA induced by vacuum-UV radiation in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Takakura, Kaoru; Ishikawa, Mitsuo; Hieda, Kotaro; Kobayashi, Katsumi; Ito, Atsushi; Ito, Takashi

    1986-09-01

    The induction of single-strand breaks in the DNA of plasmid pBR 322 by vacuum-UV radiation above 145 nm in aqueous solutions was studied in relation to the production of OH-radicals in water. The similarity and dissimilarity were examined on the wavelength dependence between the two effects. The maximum of single strand breaks at 150 nm could be explained by the action of OH-radicals derived from direct water photolysis: the maximum at 180 nm remains unexplained. There was no indication that the direct absorption of photon by the DNA molecule plays an important role in the production of single-strand breaks.

  12. Single-strand breaks in supercoiled DNA induced by vacuum-UV radiation in aqueous solution

    International Nuclear Information System (INIS)

    Takakura, Kaoru; Ishikawa, Mitsuo; Hieda, Kotaro; Kobayashi, Katsumi; Ito, Atsushi; Ito, Takashi

    1986-01-01

    The induction of single-strand breaks in the DNA of plasmid pBR 322 by vacuum-UV radiation above 145 nm in aqueous solutions was studied in relation to the production of OH-radicals in water. The similarity and dissimilarity were examined on the wavelength dependence between the two effects. The maximum of single strand breaks at 150 nm could be explained by the action of OH-radicals derived from direct water photolysis: the maximum at 180 nm remains unexplained. There was no indication that the direct absorption of photon by the DNA molecule plays an important role in the production of single-strand breaks. (author)

  13. Effects of heavy ions on inactivation and DNA double strand breaks in Deinococcus radiodurans R1.

    Science.gov (United States)

    Zimmermann, H; Schafer, M; Schmitz, C; Bucker, H

    1994-10-01

    Inactivation and double strand break (dsb) induction after heavy ion irradiation were studied in stationary phase cells of the highly radiation resistant bacterium Deinococcus radiodurans R1. There is evidence that the radiation sensitivity of this bacterium is nearly independent on energy in the range of up to 15 MeV/u for lighter ions (Ar). The responses to dsb induction for charged particles show direct relationship between increasing radiation dose and residual intact DNA.

  14. Inductive Monitoring System (IMS)

    Data.gov (United States)

    National Aeronautics and Space Administration — IMS: Inductive Monitoring System The Inductive Monitoring System (IMS) is a tool that uses a data mining technique called clustering to extract models of normal...

  15. A rapid and practical strategy for the determination of platinum, palladium, ruthenium, rhodium, iridium and gold in large amounts of ultrabasic rock by inductively coupled plasma optical emission spectrometry combined with ultrasound extraction

    Science.gov (United States)

    Zhang, Gai; Tian, Min

    2015-04-01

    This proposed method regulated the determination of platinum, palladium, ruthenium, rhodium, iridium and gold in platinum-group ores by nickel sulfide fire assay—inductively coupled plasma optical emission spectrometry (ICP-OES) combined with ultrasound extraction for the first time. The quantitative limits were 0.013-0.023μg/g. The samples were fused to separate the platinum-group elements from matrix. The nickel sulfide button was then dissolved with hydrochloric acid and the insoluble platinum-group sulfide residue was dissolved with aqua regia by ultrasound bath and finally determined by ICP-OES. The proposed method has been applied into the determination of platinum-group element and gold in large amounts of ultrabasic rocks from the Great Dyke of Zimbabwe.

  16. Probing the two-scale-factor universality hypothesis by exact rotation symmetry-breaking mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Neto, J.F.S.; Lima, K.A.L.; Carvalho, P.R.S. [Universidade Federal do Piaui, Departamento de Fisica, Teresina, PI (Brazil); Sena-Junior, M.I. [Universidade de Pernambuco, Escola Politecnica de Pernambuco, Recife, PE (Brazil); Universidade Federal de Alagoas, Instituto de Fisica, Maceio, AL (Brazil)

    2017-12-15

    We probe the two-scale-factor universality hypothesis by evaluating, firstly explicitly and analytically at the one-loop order, the loop quantum corrections to the amplitude ratios for O(N)λφ{sup 4} scalar field theories with rotation symmetry breaking in three distinct and independent methods in which the rotation symmetry-breaking mechanism is treated exactly. We show that the rotation symmetry-breaking amplitude ratios turn out to be identical in the three methods and equal to their respective rotation symmetry-breaking ones, although the amplitudes themselves, in general, depend on the method employed and on the rotation symmetry-breaking parameter. At the end, we show that all these results can be generalized, through an inductive process based on a general theorem emerging from the exact calculation, to any loop level and physically interpreted based on symmetry ideas. (orig.)

  17. load loss performance of an autonomous self-excited induction

    African Journals Online (AJOL)

    ES Obe

    Seyoum, D. and Wolf, P., Self Excited In- duction Generators for Breaking Van Appli- cations, Proc. AUPEC, Brisbane Australia,. September, 2004. 12. Wang, L. and Su, J. Dynamic Performance of an isolated Self-Excited Induction gener- ator under various loading conditions, IEEE. Trans. on Energy Conversion, Vol. 14, No.

  18. DNA strand breaks, repair, and survival in x-irradiated mammalian cells

    International Nuclear Information System (INIS)

    Dugle, D.L.; Gillespie, C.J.; Chapman, J.D.

    1976-01-01

    The yields of unrepairable single- and double-strand breaks in the DNA of x-irradiated Chinese hamster cells were measured by low-speed neutral and alkaline sucrose density gradient sedimentation in order to investigate the relation between these lesions and reproductive death. After maximal single-strand rejoining, at all doses, the number of residual single-strand breaks was twice the number of residual double-strand breaks. Both double-strand and unrepairable single-strand breaks were proportional to the square of absorbed dose, in the range 10-50 krad. No rejoining of double-strand breaks was observed. These observations suggest that, in mammalian cells, most double-strand breaks are not repairable, while all single-strand breaks are repaired except those that are sufficiently close on complementary strands to constitute double-strand breaks. Comparison with cell survival measurements at much lower doses suggests that loss of reproductive capacity corresponds to induction of approximately one double-strand break

  19. Inductive Reasoning and Writing

    Science.gov (United States)

    Rooks, Clay; Boyd, Robert

    2003-01-01

    Induction, properly understood, is not merely a game, nor is it a gimmick, nor is it an artificial way of explaining an element of reasoning. Proper understanding of inductive reasoning--and the various types of reasoning that the authors term inductive--enables the student to evaluate critically other people's writing and enhances the composition…

  20. Induction machine handbook

    CERN Document Server

    Boldea, Ion

    2002-01-01

    Often called the workhorse of industry, the advent of power electronics and advances in digital control are transforming the induction motor into the racehorse of industrial motion control. Now, the classic texts on induction machines are nearly three decades old, while more recent books on electric motors lack the necessary depth and detail on induction machines.The Induction Machine Handbook fills industry's long-standing need for a comprehensive treatise embracing the many intricate facets of induction machine analysis and design. Moving gradually from simple to complex and from standard to

  1. Rapid and sensitive determination of radiocesium (Cs-135, Cs-137) in the presence of excess barium by electrothermal vaporization-inductively coupled plasma-mass spectrometry (ETV-ICP-MS) with potassium thiocyanate as modifier

    International Nuclear Information System (INIS)

    Song, M.; Probst, T.U.; Berryman, N.G.

    2001-01-01

    An electrothermal vaporization-inductively coupled plasma-mass spectrometric (ETV-ICP-MS) method based on selective volatilization of cesium with KSCN as modifier has been developed for determination of radiocesium, i.e. 135 Cs and 137 Cs, in the presence of isobaric barium. A 10000 times excess of barium, which was volatilized at a temperature of 1100 C, resulted only in a 1% signal increase in the signal of mass 135 amu. The recommended concentration of KSCN is 0.3 mM, and pretreatment and volatilization temperatures are 400 C and 1100 C, respectively. A ramp time of 1 s is recommended for the volatilization step. The achieved limit of detection for 135 Cs is 0.2 pg/mL (10 μBq/mL) and 4 fg (0.2 μBq) absolute for a sample volume of 20 μL. This means a limit of detection for 137 Cs of 0.2 pg/mL (0.6 Bq/mL) and of 4 fg (0.01 Bq) absolute. Signal variations of 135 Cs and 137 Cs, respectively, in spiked samples with various matrices were investigated. (orig.)

  2. Rapid and long-term induction of effector immediate early genes (BDNF, Neuritin and Arc) in peri-infarct cortex and dentate gyrus after ischemic injury in rat brain

    DEFF Research Database (Denmark)

    Rickhag, Karl Mattias; Teilum, Maria; Wieloch, Tadeusz

    2007-01-01

    including cerebral cortex and hippocampus. Brain-derived neurotrophic factor (BDNF), Neuritin and Activity-regulated cytoskeleton-associated protein (Arc) belong to a subgroup of immediate early genes implicated in synaptic plasticity known as effector immediate early genes. Here, we investigated...... at 0-6 h of reperfusion for Neuritin and 0-12 h of reperfusion for Arc while BDNF was induced 0-9 h of reperfusion. Our study demonstrates a rapid and long-term activation of effector immediate early genes in distinct brain areas following ischemic injury in rat. Effector gene activation may be part...

  3. Rock Directed Breaking Under the Impulse Load

    Science.gov (United States)

    Khomeriki, Sergo; Mataradze, Edgar; Chikhradze, Nikoloz; Losaberidze, Marine; Khomeriki, Davit; Shatberashvili, Grigol

    2016-10-01

    In the work the problem of directed chipping of facing stone material by means of managing of explosion process is considered. The technology of the mining of decorative stone by the use of explosion energy means the very rapid transfer of potential energy of elastic deformations to kinetic energy. As a result, the explosion impulse, in the expanse of the inertia of rock massive, does not cause the increase of existing cracks. In the course of explosion, the shock wave is propagated by ultrasonic velocity and in this case the medium parameters (pressure, density, temperature, velocity) increase in spurts. In spite of this fact the all three conservation laws of mechanics remain valid on basis of three laws the equations are derived by which the parameters of shock wave may be defined by means of the rock physical-mechanical properties. The load on the body volume at breaking under explosion acts over very small period of the time. Therefore, stressed-deformed state of the rock was studied when the impulse load acts on the boundary. It was considered that the mining of the blocks of facing stone is performed from the hard rocks. This means that the breaking proceeds in the zone of elastic deformation. In the conditions of mentioned assumptions, the expression of the stress tensor and displacement of vector components initiated by stressed-deformed state in the rock are written.

  4. Breaking strain of neutron star crust and gravitational waves.

    Science.gov (United States)

    Horowitz, C J; Kadau, Kai

    2009-05-15

    Mountains on rapidly rotating neutron stars efficiently radiate gravitational waves. The maximum possible size of these mountains depends on the breaking strain of the neutron star crust. With multimillion ion molecular dynamics simulations of Coulomb solids representing the crust, we show that the breaking strain of pure single crystals is very large and that impurities, defects, and grain boundaries only modestly reduce the breaking strain to around 0.1. Because of the collective behavior of the ions during failure found in our simulations, the neutron star crust is likely very strong and can support mountains large enough so that their gravitational wave radiation could limit the spin periods of some stars and might be detectable in large-scale interferometers. Furthermore, our microscopic modeling of neutron star crust material can help analyze mechanisms relevant in magnetar giant flares and microflares.

  5. DNA single strand break in fibroblast from Down syndrome patients

    International Nuclear Information System (INIS)

    Rozga, B.

    1992-01-01

    The radiosensitivity of tree trisomic (trisomia +21) strains of human fibroblasts to gamma radiation has been investigated in vitro and the causes of induction and repair of single strand DNA breaks in these cells have been estimated. The single strand breaks in DNA of normal and trisomic cells have been found to be ameliorated with an approximately equal efficiency. Repair has been found to be three times slower in trisomic cells compared to their normal relevant, most likely due to their elevated sensitivity to ionizing radiation and the following mortality of trisomic cells, and/or the potential occurrence of a great number of chromosome aberrations in cells irradiated in vitro. (author). 28 refs, 4 figs, 1 tab

  6. The role of DNA double-strand breaks in spontaneous homologous recombination in S. cerevisiae

    DEFF Research Database (Denmark)

    Lettier, Gaëlle; Feng, Q.; Mayolo, A.A. de

    2006-01-01

    of meiosis and result from the induction of a large number of DNA double-strand breaks (DSBs). By analogy, it is generally believed that the rare spontaneous mitotic HR events are due to repair of DNA DSBs that accidentally occur during mitotic growth. Here we provide the first direct evidence that most...

  7. Repair of near-UV (365nm or 313 nm) induced DNA strand breaks

    International Nuclear Information System (INIS)

    Miguel, A.G.

    1981-01-01

    The action of near-UV (365 nm or 313 nm) radiation in cellular inactivaton (biological measurements) and induction and repair of breaks (physical measurements) is studied in repair proficient strain and in pol A, rec A and uvr A deficient strains of Escherichia coli K-12. (M.A.C.) [pt

  8. String breaking with Wilson loops?

    CERN Document Server

    Kratochvila, S; Kratochvila, Slavo; Forcrand, Philippe de

    2003-01-01

    A convincing, uncontroversial observation of string breaking, when the static potential is extracted from Wilson loops only, is still missing. This failure can be understood if the overlap of the Wilson loop with the broken string is exponentially small. In that case, the broken string ground state will only be seen if the Wilson loop is long enough. Our preliminary results show string breaking in the context of the 3d SU(2) adjoint static potential, using the L\\"uscher-Weisz exponential variance reduction approach. As a by-product, we measure the fundamental SU(2) static potential with improved accuracy and see clear deviations from Casimir scaling.

  9. Influence of night-breaks on flowering and phytohormones content in Hyoscyamus niger L.

    Directory of Open Access Journals (Sweden)

    Jan Kopcewicz

    2014-01-01

    Full Text Available Night-breaks caused both stimulated shoot growth and caused formation of flowers as well as a general increase in the content of phytohormones in leaves of the long-day plant Hyoscyamus niger L. At the time of flower formation in night-break treated plants, new gibberellin-like substances also appear. The results show that night-breaks cause similar changes in the phytohormones content as a long inductive photoperiod. It may be assumed that independently of the way of induction, the generative differentiation of long-day plants is always accompanied by a general increase in the amount of endogenous hormones and the appearance of new gibberellins. These results suggest the possibility of a morphogenetic role of hormones, especially gibberellins, in the phenomena of flower formation and differentiation.

  10. Alkaline gel electrophoresis assay to detect DNA strand breaks and repair mechanisms in Escherichia coli

    International Nuclear Information System (INIS)

    Mattos, Jose Carlos Pelielo de; Motta, Ellen Serri da; Oliveira, Marcia Betania Nunes de; Dantas, Flavio Jose da Silva; Araujo, Adriano Caldeira de

    2008-01-01

    Reactive oxygen species (ROS) can induce lesions in different cellular targets, including DNA. Stannous chloride (SnCl 2 ) is a ROS generator, leading to lethality in Escherichia coli (E. coli), with the base excision repair (BER) mechanism playing a role in this process. Many techniques have been developed to detect genotoxicity, as comet assay, in eukaryotic cells, and plasmid DNA agarose gel electrophoresis. In this study, an adaptation of the alkaline gel electrophoresis method was carried out to ascertain the induction of strand breaks by SnCl 2 in bacterial DNA, from E. coli BER mutants, and its repair pathway. Results obtained show that SnCl 2 was able to induce DNA strand breaks in all strains tested. Moreover, endonuclease IV and exonuclease III play a role in DNA repair. On the whole, data has shown that the alkaline gel electrophoresis assay could be used both for studying DNA strand breaks induction and for associated repair mechanisms. (author)

  11. Current topics in DNA double-strand break repair

    International Nuclear Information System (INIS)

    Kobayashi, Junya; Takata, Minoru; Iwabuchi, Kuniyoshi; Miyagawa, Kiyoshi; Sonoda, Eiichiro; Suzuki, Keiji; Tauchi, Hiroshi

    2008-01-01

    DNA double strand break (DSB) is one of the most critical types of damage which is induced by ionizing radiation. In this review, we summarize current progress in investigations on the function of DSB repair-related proteins. We focused on recent findings in the analysis of the function of proteins such as 53BP1, histone H2AX, Mus81-Eme1, Fanc complex, and UBC13, which are found to be related to homologous recombination repair or to non-homologous end joining. In addition to the function of these proteins in DSB repair, the biological function of nuclear foci formation following DSB induction is discussed. (author)

  12. Code breaking in the pacific

    CERN Document Server

    Donovan, Peter

    2014-01-01

    Covers the historical context and the evolution of the technically complex Allied Signals Intelligence (Sigint) activity against Japan from 1920 to 1945 Describes, explains and analyzes the code breaking techniques developed during the war in the Pacific Exposes the blunders (in code construction and use) made by the Japanese Navy that led to significant US Naval victories

  13. Strong coupling electroweak symmetry breaking

    International Nuclear Information System (INIS)

    Barklow, T.L.; Burdman, G.; Chivukula, R.S.

    1997-04-01

    The authors review models of electroweak symmetry breaking due to new strong interactions at the TeV energy scale and discuss the prospects for their experimental tests. They emphasize the direct observation of the new interactions through high-energy scattering of vector bosons. They also discuss indirect probes of the new interactions and exotic particles predicted by specific theoretical models

  14. Appointment breaking: causes and solutions.

    Science.gov (United States)

    Bean, A G; Talaga, J

    1992-12-01

    From a review of research on health care appointment breaking, the authors find that patient demographic characteristics, psychosocial problems, previous appointment keeping, health beliefs, and situational factors predict no-show behavior. Suggestions are offered for designing the marketing mix to increase patient appointment keeping. Methods for mitigating the negative effects of no-shows on health care providers are described.

  15. Strong coupling electroweak symmetry breaking

    Energy Technology Data Exchange (ETDEWEB)

    Barklow, T.L. [Stanford Linear Accelerator Center, Menlo Park, CA (United States); Burdman, G. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Physics; Chivukula, R.S. [Boston Univ., MA (United States). Dept. of Physics

    1997-04-01

    The authors review models of electroweak symmetry breaking due to new strong interactions at the TeV energy scale and discuss the prospects for their experimental tests. They emphasize the direct observation of the new interactions through high-energy scattering of vector bosons. They also discuss indirect probes of the new interactions and exotic particles predicted by specific theoretical models.

  16. Oil prices: Breaks and trends

    International Nuclear Information System (INIS)

    Noguera, José

    2013-01-01

    This paper contributes to the literature of the stationarity of financial time series and the literature on oil and macroeconomics in several ways. First, it uses Kejriwal and Perron (2010) sequential procedure to endogenously determine multiple structural changes in real oil prices without facing the circular testing problem between structural changes and stationary assumptions of previous tests. Second, it performs a diagnostic check to detect the significance and magnitude of the potential breaks. Third, it uses the above information to test for the existence of stochastic trends in real oil prices, and fourth, it speculates about possible explanations for the break dates found in order to encourage further work and discussions. The exercise uses monthly data from January 1861 to August 2011. - Highlights: ► The model endogenously determine multiple structural changes in real oil prices. ► The methods used does not face the circular testing problem. ► It also detect the significance and magnitude of the breaks detected. ► It tests for the existence of stochastic trends. ► It explains the reasons for the break dates found

  17. Instantons and chiral symmetry breaking

    International Nuclear Information System (INIS)

    Carneiro, C.E.I.; McDougall, N.A.

    1984-01-01

    A detailed investigation of chiral symmetry breaking due to instanton dynamics is carried out, within the framework of the dilute gas approximation, for quarks in both the fundamental and adjoint representations of SU(2). The momentum dependence of the dynamical mass is found to be very similar in each representation. (orig.)

  18. Instantons and chiral symmetry breaking

    Energy Technology Data Exchange (ETDEWEB)

    Carneiro, C.E.I.; McDougall, N.A. (Oxford Univ. (UK). Dept. of Theoretical Physics)

    1984-10-22

    A detailed investigation of chiral symmetry breaking due to instanton dynamics is carried out, within the framework of the dilute gas approximation, for quarks in both the fundamental and adjoint representations of SU(2). The momentum dependence of the dynamical mass is found to be very similar in each representation.

  19. Inflationary implications of supersymmetry breaking

    NARCIS (Netherlands)

    Borghese, Andrea; Roest, Diederik; Zavala, Ivonne

    2013-01-01

    We discuss a general bound on the possibility to realise inflation in any minimal supergravity with F-terms. The derivation crucially depends on the sGoldstini, the scalar field directions that are singled out by spontaneous supersymmetry breaking. The resulting bound involves both slow-roll

  20. Aluminum break-point contacts

    NARCIS (Netherlands)

    Heinemann, Martina; Groot, R.A. de

    1997-01-01

    Ab initio molecular dynamics is used to study the contribution of a single Al atom to an aluminum breakpoint contact during the final stages of breaking and the initial stages of the formation of such a contact. A hysteresis effect is found in excellent agreement with experiment and the form of the

  1. Breaking Carbon Lock-in

    DEFF Research Database (Denmark)

    Driscoll, Patrick Arthur

    2014-01-01

    This central focus of this paper is to highlight the ways in which path dependencies and increasing returns (network effects) serve to reinforce carbon lock-in in large-scale road transportation infrastructure projects. Breaking carbon lock-in requires drastic changes in the way we plan future...

  2. Parental Break-Ups and Stress

    DEFF Research Database (Denmark)

    Dissing, Agnete S.; Dich, Nadya; Nybo Andersen, Anne-Marie

    2017-01-01

    Background: Parental break-up is wide spread, and the effects of parental break-up on children’s well-being are known. The evidence regarding child age at break-up and subsequent family arrangements is inconclusive. Aim: to estimate the effects of parental break-up on stress in pre-adolescent chi......Background: Parental break-up is wide spread, and the effects of parental break-up on children’s well-being are known. The evidence regarding child age at break-up and subsequent family arrangements is inconclusive. Aim: to estimate the effects of parental break-up on stress in pre......-adolescent children with a specific focus on age at break-up and post-breakup family arrangements. Methods: We used data from the Danish National Birth Cohort. Participants included 44 509 children followed from birth to age 11. Stress was self-reported by children at age 11, when the children also reported...... on parental break-up and post break-up family arrangements. Results: Twenty-one percent of the children had experienced a parental break-up at age 11, and those who had experienced parental break-up showed a higher risk of stress (OR:1.72, 95%CI:1.55;1.91) regardless of the child’s age at break-up. Children...

  3. Immediate and repair induced DNA double strand breaks in mammalian cells

    International Nuclear Information System (INIS)

    Bryant, P.E.

    1986-01-01

    It seems logical to postulate that double strand breaks (dsb) arising both at the time of irradiation and via repair processes are potentially equally damaging for a cell in terms of the potential to induce chromosomal aberrations. However, in some cell systems the repair of double es or es-ssb sites may run concurrently with the incision so that these lesions do not remain open for long: hence the lack of accumulation of dsb during repair. The rate of incision will thus determine both the accumulation and the probability of exchanges leading to chromosomal aberrations between these and other frank dsb. Rapid incision leading to a large additional pool of dsb appears to be the case in Chinese hamster V79 cells. Some evidence also exists for the conversion of base damage, via dsb, into deletion type chromatid aberrations which accumulate in irradiated G2 human cells treated with ara C. A small fraction of dsb, probably arising both at the time of irradiation as well as enzymatically during repair of base or sugar damage, appears to be either left unrepaired, yielding deletion type chromosomal aberrations, or is misrepaired, yielding exchange aberrations. The induction of these aberrations appears to be of central importance in the biological effects of ionizing radiation such as mutations, oncogenic transformation, and cell death. 52 refs., 5 figs

  4. Application of forgetful analgesia induction in induction period in patients with obstructive jaundice

    Directory of Open Access Journals (Sweden)

    Wei DU

    2014-03-01

    Full Text Available Objective To observe the effect of forgetful analgesia induction and tracheal intubation on the hemodynamic changes in induction period in patients with obstructive jaundice, and explore a safe method for anesthesia induction and tracheal intubation. Methods Sixty patients with obstructive jaundice undergoing elective abdominal operation in General Hospital of PLA from February, 2013 to August, 2013 were involved in the present study. Participants included 36 male and 24 female patients, aging 19-65 years (mean 42±5 years, weighing 47-73 kg (mean 54±6 kg, with ASA Ⅰ-Ⅱ. These 60 patients were randomly divided into forgetful analgesia induction-tracheal intubation group (group A, n=30 and rapid induction-tracheal intubation group (group B, n=30. The heart rate (HR, mean arterial pressure (MAP, pulse oxygen saturation (SpO2 at the time point of before induction (T0, before intubation (T1, at the moment of intubation (T2 and 3 min after intubation (T3 were determined in both groups. Administration times of ephedrine hydrochloride and atropine was recorded in both groups. Results There was no significant difference in HR, MAP, SpO2 before and after induction in group A. In the patients of group B, the HR increased and MAP decreased after induction compared with those before induction (P<0.05, and the change of SpO2 was not significant. Ephedrine hydrochloride and atropine were administrated in both groups, and the cases and times of ephedrine hydrochloride administration were more in group B than in group A (P<0.05. Conclusion The forgetful analgesia induction-tracheal intubation could effectively control the stress response and reduce the fluctuation in hemodynamics during induction of anesthesia in patients with obstructive jaundice. DOI: 10.11855/j.issn.0577-7402.2014.02.15

  5. Improving long term driving comfort by taking breaks - how break activity affects effectiveness

    OpenAIRE

    Sammonds, GM; Mansfield, NJ; Fray, M

    2017-01-01

    During long duration journeys, drivers are encouraged to take regular breaks. The benefits of breaks have been documented for safety; breaks may also be beneficial for comfort. The activity undertaken during a break may influence its effectiveness. Volunteers completed 3 journeys on a driving simulator. Each 130 min journey included a 10 min break after the first hour. During the break volunteers either stayed seated, left the simulator and sat in an adjacent room, or took a walk on a treadmi...

  6. A model of intrinsic symmetry breaking

    International Nuclear Information System (INIS)

    Ge, Li; Li, Sheng; George, Thomas F.; Sun, Xin

    2013-01-01

    Different from the symmetry breaking associated with a phase transition, which occurs when the controlling parameter is manipulated across a critical point, the symmetry breaking presented in this Letter does not need parameter manipulation. Instead, the system itself suddenly undergoes symmetry breaking at a certain time during its evolution, which is intrinsic symmetry breaking. Through a polymer model, it is revealed that the origin of the intrinsic symmetry breaking is nonlinearity, which produces instability at the instance when the evolution crosses an inflexion point, where this instability breaks the original symmetry

  7. DN2 Thymocytes Activate a Specific Robust DNA Damage Response to Ionizing Radiation-Induced DNA Double-Strand Breaks

    Directory of Open Access Journals (Sweden)

    Irene Calvo-Asensio

    2018-06-01

    Full Text Available For successful bone marrow transplantation (BMT, a preconditioning regime involving chemo and radiotherapy is used that results in DNA damage to both hematopoietic and stromal elements. Following radiation exposure, it is well recognized that a single wave of host-derived thymocytes reconstitutes the irradiated thymus, with donor-derived thymocytes appearing about 7 days post BMT. Our previous studies have demonstrated that, in the presence of donor hematopoietic cells lacking T lineage potential, these host-derived thymocytes are able to generate a polyclonal cohort of functionally mature peripheral T cells numerically comprising ~25% of the peripheral T cell pool of euthymic mice. Importantly, we demonstrated that radioresistant CD44+ CD25+ CD117+ DN2 progenitors were responsible for this thymic auto-reconstitution. Until recently, the mechanisms underlying the radioresistance of DN2 progenitors were unknown. Herein, we have used the in vitro “Plastic Thymus” culture system to perform a detailed investigation of the mechanisms responsible for the high radioresistance of DN2 cells compared with radiosensitive hematopoietic stem cells. Our results indicate that several aspects of DN2 biology, such as (i rapid DNA damage response (DDR activation in response to ionizing radiation-induced DNA damage, (ii efficient repair of DNA double-strand breaks, and (iii induction of a protective G1/S checkpoint contribute to promoting DN2 cell survival post-irradiation. We have previously shown that hypoxia increases the radioresistance of bone marrow stromal cells in vitro, at least in part by enhancing their DNA double-strand break (DNA DSB repair capacity. Since the thymus is also a hypoxic environment, we investigated the potential effects of hypoxia on the DDR of DN2 thymocytes. Finally, we demonstrate for the first time that de novo DN2 thymocytes are able to rapidly repair DNA DSBs following thymic irradiation in vivo.

  8. Urofollitropin and ovulation induction

    NARCIS (Netherlands)

    van Wely, Madelon; Yding Andersen, Claus; Bayram, Neriman; van der Veen, Fulco

    2005-01-01

    Anovulation is a common cause of female infertility. Treatment for women with anovulation is aimed at induction of ovulation. Ovulation induction with follicle-stimulating hormone (FSH) is indicated in women with WHO type II anovulation in whom treatment with clomifene citrate (clomifene) has

  9. Three methods to determine the yields of DNA double-strand breaks

    International Nuclear Information System (INIS)

    Erzgraeber, G.; Lapidus, I.L.

    1985-01-01

    A possibility of determining the yield of DNA double-strand breaks in cells of the Chinese hamster (V79-4) by finding the amount of DNA released as a result of breaks and by determining the relative sedimentation velocity of DNA-membrane complexes affected by ionizing radiations with different physical characteristics is discussed. Results of the analysis are compared with the data obtained by a traditional method of sedimentation in the neutral sucrose density gradient. Comparative characterization of the methods is discussed. The yields of DNA double-strand breaks determined by the suggested independent methods are in good agreement, which opens possibilities of studying induction and repair of double-strand breaks by means of simpler and more reliable methods

  10. Inductance loop and partial

    CERN Document Server

    Paul, Clayton R

    2010-01-01

    "Inductance is an unprecedented text, thoroughly discussing "loop" inductance as well as the increasingly important "partial" inductance. These concepts and their proper calculation are crucial in designing modern high-speed digital systems. World-renowned leader in electromagnetics Clayton Paul provides the knowledge and tools necessary to understand and calculate inductance." "With the present and increasing emphasis on high-speed digital systems and high-frequency analog systems, it is imperative that system designers develop an intimate understanding of the concepts and methods in this book. Inductance is a much-needed textbook designed for senior and graduate-level engineering students, as well as a hands-on guide for working engineers and professionals engaged in the design of high-speed digital and high-frequency analog systems."--Jacket.

  11. Half Bridge Inductive Heater

    Directory of Open Access Journals (Sweden)

    Zoltán GERMÁN-SALLÓ

    2015-12-01

    Full Text Available Induction heating performs contactless, efficient and fast heating of conductive materials, therefore became one of the preferred heating procedure in industrial, domestic and medical applications. During induction heating the high-frequency alternating currents that heat the material are induced by means of electromagnetic induction. The material to be heated is placed inside the time-varying magnetic field generated by applying a highfrequency alternating current to an induction coil. The alternating electromagnetic field induces eddy currents in the workpiece, resulting resistive losses, which then heat the material. This paper describes the design of a power electronic converter circuit for induction heating equipment and presents the obtained results. The realized circuit is a low power half bridge resonant inverter which uses power MOS transistors and adequate driver circuits.

  12. Physics of chiral symmetry breaking

    International Nuclear Information System (INIS)

    Shuryak, E.V.

    1991-01-01

    This subsection of the 'Modeling QCD' Workshop has included five talks. E. Shuryak spoke on 'Recent Progress in Understanding Chiral Symmetry Breaking'; below it is split into two parts: (i) a mini-review of the field and (ii) a brief presentation of the status of the theory of interacting instantons. The next sections correspond to the following talks: (iii) K. Goeke et al., 'Chiral Restoration and Medium Corrections to Nucleon in the NJL Model'; (iv) M. Takizawa and K. Kubodera, 'Study of Meson Properties and Quark Condensates in the NJL Model with Instanton Effects'; (v) G. Klein and A. G. Williams, 'Dynamical Chiral Symmetry Breaking in Dual QCD'; and (vi) R. D. Ball, 'Skyrmions and Baryons.' (orig.)

  13. Supersymmetry breaking by gaugino condensation

    International Nuclear Information System (INIS)

    Casas, J.A.

    1991-01-01

    We briefly review the status and some of the recent work on supersymmetry breaking by gaugino condensation effects in the context of superstring theories. This issue is intimately related to the structure of the effective potential coming from superstrings. Minimization of this not only allows to find the scale of supersymmetry breaking, but also to determine dynamically other fundamental parameters of the theory, in particular the gauge coupling constant at the unification point and the expectation values of the moduli which give the size and shape of the compactified space. In a multiple condensate scenario these get reasonable values which may, in turn, lead to a determination of the family mass hierarchy. Some directions for future work are examined too. (author). 23 refs

  14. Post accidental small breaks analysis

    International Nuclear Information System (INIS)

    Depond, G.; Gandrille, J.

    1980-04-01

    EDF ordered to FRAMATOME by 1977 to complete post accidental long term studies on 'First Contrat-Programme' reactors, in order to demonstrate the safety criteria long term compliance, to get information on NSSS behaviour and to improve the post accidental procedures. Convenient analytical models were needed and EDF and FRAMATOME respectively developped the AXEL and FRARELAP codes. The main results of these studies is that for the smallest breaks, it is possible to manually undertake cooling and pressure reducing actions by dumping the steam generators secondary side in order to meet the RHR operating specifications and perform long term cooling through this system. A specific small breaks procedure was written on this basis. The EDF and FRAMATOME codes are continuously improved; the results of a French set of separate effects experiments will be incorporated as well as integral system verification

  15. Prophylactic treatment of retinal breaks

    DEFF Research Database (Denmark)

    Blindbæk, Søren Leer; Grauslund, Jakob

    2015-01-01

    Prophylactic treatment of retinal breaks has been examined in several studies and reviews, but so far, no studies have successfully applied a systematic approach. In the present systematic review, we examined the need of follow-up after posterior vitreous detachment (PVD) - diagnosed by slit...... published before 2012. Four levels of screening identified 13 studies suitable for inclusion in this systematic review. No meta-analysis was conducted as no data suitable for statistical analysis were identified. In total, the initial examination after symptomatic PVD identified 85-95% of subsequent retinal......-47% of cases, respectively. The cumulated incidence of RRD despite prophylactic treatment was 2.1-8.8%. The findings in this review suggest that follow-up after symptomatic PVD is only necessary in cases of incomplete retinal examination at presentation. Prophylactic treatment of symptomatic retinal breaks...

  16. Breaking through the tranfer tunnel

    CERN Document Server

    Laurent Guiraud

    2001-01-01

    This image shows the tunnel boring machine breaking through the transfer tunnel into the LHC tunnel. Proton beams will be transferred from the SPS pre-accelerator to the LHC at 450 GeV through two specially constructed transfer tunnels. From left to right: LHC Project Director, Lyn Evans; CERN Director-General (at the time), Luciano Maiani, and Director for Accelerators, Kurt Hubner.

  17. Models of electroweak symmetry breaking

    CERN Document Server

    Pomarol, Alex

    2015-01-01

    This chapter present models of electroweak symmetry breaking arising from strongly interacting sectors, including both Higgsless models and mechanisms involving a composite Higgs. These scenarios have also been investigated in the framework of five-dimensional warped models that, according to the AdS/CFT correspondence, have a four-dimensional holographic interpretation in terms of strongly coupled field theories. We explore the implications of these models at the LHC.

  18. Supersymmetry breaking at finite temperature

    International Nuclear Information System (INIS)

    Kratzert, K.

    2002-11-01

    The mechanism of supersymmetry breaking at finite temperature is still only partly understood. Though it has been proven that temperature always breaks supersymmetry, the spontaneous nature of this breaking remains unclear, in particular the role of the Goldstone fermion. The aim of this work is to unify two existing approaches to the subject. From a hydrodynamic point of view, it has been argued under very general assumptions that in any supersymmetric quantum field theory at finite temperature there should exist a massless fermionic collective excitation, named phonino because of the analogy to the phonon. In the framework of a self-consistent resummed perturbation theory, it is shown for the example of the Wess-Zumino model that this mode fits very well into the quantum field theoretical framework pursued by earlier works. Interpreted as a bound state of boson and fermion, it contributes to the supersymmetric Ward-Takahashi identities in a way showing that supersymmetry is indeed broken spontaneously with the phonino playing the role of the Goldstone fermion. The second part of the work addresses the case of supersymmetric quantum electrodynamics. It is shown that also here the phonino exists and must be interpreted as the Goldstone mode. This knowledge allows a generalization to a wider class of models. (orig.)

  19. Mammalian DNA single-strand break repair: an X-ra(y)ted affair.

    Science.gov (United States)

    Caldecott, K W

    2001-05-01

    The genetic stability of living cells is continuously threatened by the presence of endogenous reactive oxygen species and other genotoxic molecules. Of particular threat are the thousands of DNA single-strand breaks that arise in each cell, each day, both directly from disintegration of damaged sugars and indirectly from the excision repair of damaged bases. If un-repaired, single-strand breaks can be converted into double-strand breaks during DNA replication, potentially resulting in chromosomal rearrangement and genetic deletion. Consequently, cells have adopted multiple pathways to ensure the rapid and efficient removal of single-strand breaks. A general feature of these pathways appears to be the extensive employment of protein-protein interactions to stimulate both the individual component steps and the overall repair reaction. Our current understanding of DNA single-strand break repair is discussed, and testable models for the architectural coordination of this important process are presented. Copyright 2001 John Wiley & Sons, Inc.

  20. Review of induction LINACS

    International Nuclear Information System (INIS)

    Faltens, A.; Keefe, D.

    1981-10-01

    There has been a recent upsurge of activity in the field of induction linacs, with several new machines becoming operational and others in the design stages. The performance levels of electron machines have reached 10's of kiloamps of current and will soon reach 10's of MeV's of energy. Acceleration of ion current has been demonstrated, and the study of a 10 GeV heavy ion induction linac for ICF continues. The operating principles of induction linacs are reviewed with the emphasis on design choices which are important for increasing the maximum beam currents

  1. Review of induction linacs

    International Nuclear Information System (INIS)

    Faltens, A.; Keefe, D.

    1982-01-01

    There has been a recent upsurge of activity in the field of induction linacs, with several new machines becoming operational and others in the design stages. The performance levels of electron machines have reached 10's of kiloamps of current and will soon reach 10's of MeV's of energy. Acceleration of several kiloamps of ion current has been demonstrated, and the study of a 10 GeV heavy ion induction linac for ICF continues. The operating principles of induction linacs are reviewed with the emphasis on design choices which are important for increasing the maximum beam currents

  2. Properties of inductive reasoning.

    Science.gov (United States)

    Heit, E

    2000-12-01

    This paper reviews the main psychological phenomena of inductive reasoning, covering 25 years of experimental and model-based research, in particular addressing four questions. First, what makes a case or event generalizable to other cases? Second, what makes a set of cases generalizable? Third, what makes a property or predicate projectable? Fourth, how do psychological models of induction address these results? The key results in inductive reasoning are outlined, and several recent models, including a new Bayesian account, are evaluated with respect to these results. In addition, future directions for experimental and model-based work are proposed.

  3. To Break or Not To Break: Sex Chromosome Hemizygosity During Meiosis in Caenorhabditis.

    Science.gov (United States)

    Van, Mike V; Larson, Braden J; Engebrecht, JoAnne

    2016-11-01

    Meiotic recombination establishes connections between homologous chromosomes to promote segregation. Hemizygous regions of sex chromosomes have no homologous chromosome to recombine with, yet must be transmitted through meiosis. An extreme case of hemizygosity exists in the genus Caenorhabditis, where males have a single X chromosome that completely lacks a homologous partner. To determine whether similar strategies have evolved to accommodate hemizygosity of the X during male meiosis in Caenorhabditis with distinct modes of sexual reproduction, we examined induction and processing of meiotic double strand breaks (DSBs) in androdioecious (hermaphrodite/male) Caenorhabditis elegans and C. briggsae, and gonochoristic (female/male) C. remanei and C. brenneri Analysis of the recombinase RAD-51 suggests more meiotic DSBs are induced in gonochoristic vs. androdioecious species. However, in late prophase in all species, chromosome pairs are restructured into bivalents around a single axis, suggesting that the holocentric nature of Caenorhabditis chromosomes dictates a single crossover per bivalent regardless of the number of DSBs induced. Interestingly, RAD-51 foci were readily observed on the X chromosome of androdioecious male germ cells, while very few were detected in gonochoristic male germ cells. As in C. elegans, the X chromosome in C. briggsae male germ cells undergoes transient pseudosynapsis and flexibility in DSB repair pathway choice. In contrast, in C. remanei and C. brenneri male germ cells, the X chromosome does not undergo pseudosynapsis and appears refractory to SPO-11-induced breaks. Together our results suggest that distinct strategies have evolved to accommodate sex chromosome hemizygosity during meiosis in closely related Caenorhabditis species. Copyright © 2016 by the Genetics Society of America.

  4. Induction melter apparatus

    Science.gov (United States)

    Roach, Jay A [Idaho Falls, ID; Richardson, John G [Idaho Falls, ID; Raivo, Brian D [Idaho Falls, ID; Soelberg, Nicholas R [Idaho Falls, ID

    2008-06-17

    Apparatus and methods of operation are provided for a cold-crucible-induction melter for vitrifying waste wherein a single induction power supply may be used to effect a selected thermal distribution by independently energizing at least two inductors. Also, a bottom drain assembly may be heated by an inductor and may include an electrically resistive heater. The bottom drain assembly may be cooled to solidify molten material passing therethrough to prevent discharge of molten material therefrom. Configurations are provided wherein the induction flux skin depth substantially corresponds with the central longitudinal axis of the crucible. Further, the drain tube may be positioned within the induction flux skin depth in relation to material within the crucible or may be substantially aligned with a direction of flow of molten material within the crucible. An improved head design including four shells forming thermal radiation shields and at least two gas-cooled plenums is also disclosed.

  5. Linear induction accelerator

    Science.gov (United States)

    Buttram, M.T.; Ginn, J.W.

    1988-06-21

    A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities. 4 figs.

  6. Lessons for Inductive Germline Determination

    Science.gov (United States)

    Seervai, Riyad N.H.; Wessel, Gary M.

    2015-01-01

    SUMMARY Formation of the germline in an embryo marks a fresh round of reproductive potential, yet the developmental stage and location within the embryo where the primordial germ cells (PGCs) form differs wildly among species. In most animals, the germline is formed either by an inherited mechanism, in which maternal provisions within the oocyte drive localized germ-cell fate once acquired in the embryo, or an inductive mechanism that involves signaling between cells that directs germ-cell fate. The inherited mechanism has been widely studied in model organisms such as Drosophila melanogaster, Caenorhabditis elegans, Xenopus laevis, and Danio rerio. Given the rapid generation time and the effective adaptation for laboratory research of these organisms, it is not coincidental that research on these organisms has led the field in elucidating mechanisms for germline specification. The inductive mechanism, however, is less well understood and is studied primarily in the mouse (Mus musculus). In this review, we compare and contrast these two fundamental mechanisms for germline determination, beginning with the key molecular determinants that play a role in the formation of germ cells across all animal taxa. We next explore the current understanding of the inductive mechanism of germ-cell determination in mice, and evaluate the hypotheses for selective pressures on these contrasting mechanisms. We then discuss the hypothesis that the transition between these determination mechanisms, which has happened many times in phylogeny, is more of a continuum than a binary change. Finally, we propose an analogy between germline determination and sex determination in vertebrates—two of the milestones of reproduction and development—in which animals use contrasting strategies to activate similar pathways. PMID:23450642

  7. 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

  8. Leaders break ground for INFINITY

    Science.gov (United States)

    2008-01-01

    Community leaders from Mississippi and Louisiana break ground for the new INFINITY at NASA Stennis Space Center facility during a Nov. 20 ceremony. Groundbreaking participants included (l to r): Gottfried Construction representative John Smith, Mississippi Highway Commissioner Wayne Brown, INFINITY board member and Apollo 13 astronaut Fred Haise, Stennis Director Gene Goldman, Studio South representative David Hardy, Leo Seal Jr. family representative Virginia Wagner, Hancock Bank President George Schloegel, Mississippi Rep. J.P. Compretta, Mississippi Band of Choctaw Indians representative Charlie Benn and Louisiana Sen. A.G. Crowe.

  9. Give Young Scientists a Break

    Energy Technology Data Exchange (ETDEWEB)

    Wiley, H. S.

    2009-11-01

    There has been much concern about the impact of tight funding on the careers of young scientists. When only a small percentage of grants are approved, even the smallest problem or error with an application can push it out of the funding range. Unfortunately, the relative lack of grant writing skills by new investigators often has this effect. To avoid a situation where only experienced investigators with polished writing skills are funded, the National Institutes of Health has instituted a more generous ranking scale for new investigators. Not surprisingly, some senior investigators have protested, calling it reverse discrimination. I say that their anger is misplaced. New investigators do deserve a break.

  10. Inflationary implications of supersymmetry breaking

    Energy Technology Data Exchange (ETDEWEB)

    Borghese, Andrea; Roest, Diederik; Zavala, Ivonne [Centre for Theoretical Physics, University of Groningen, Nijenborgh 4, 9747 AG Groningen (Netherlands)

    2013-07-23

    We discuss a general bound on the possibility to realise inflation in any minimal supergravity with F-terms. The derivation crucially depends on the sGoldstini, the scalar field directions that are singled out by spontaneous supersymmetry breaking. The resulting bound involves both slow-roll parameters and the geometry of the Kähler manifold of the chiral scalars. We analyse the inflationary implications of this bound, and in particular discuss to what extent the requirements of single field and slow-roll can both be met in F-term inflation.

  11. History of electroweak symmetry breaking

    International Nuclear Information System (INIS)

    Kibble, T W B

    2015-01-01

    In this talk, I recall the history of the development of the unified electroweak theory, incorporating the symmetry-breaking Higgs mechanism, as I saw it from my standpoint as a member of Abdus Salam's group at Imperial College. I start by describing the state of physics in the years after the Second World War, explain how the goal of a unified gauge theory of weak and electromagnetic interactions emerged, the obstacles encountered, in particular the Goldstone theorem, and how they were overcome, followed by a brief account of more recent history, culminating in the historic discovery of the Higgs boson in 2012. (paper)

  12. Sediment transport under breaking waves

    DEFF Research Database (Denmark)

    Christensen, Erik Damgaard; Hjelmager Jensen, Jacob; Mayer, Stefan

    2000-01-01

    The sediment transport in the surf zone is modelled by combining a Navier-Stokes solver, a free surface model, a turbulence model, and a sediment transport model. The flow solver is based on the finite volume technique for non-orthogonal grids. The model is capable of simulating the turbulence...... generated at the surface where the wave breaks as well as the turbulence generated near the bed due to the wave-motion and the undertow. In general, the levels of turbulent kinetic energy are found to be higher than experiments show. This results in an over prediction of the sediment transport. Nevertheless...

  13. Structural Break Tests Robust to Regression Misspecification

    Directory of Open Access Journals (Sweden)

    Alaa Abi Morshed

    2018-05-01

    Full Text Available Structural break tests for regression models are sensitive to model misspecification. We show—analytically and through simulations—that the sup Wald test for breaks in the conditional mean and variance of a time series process exhibits severe size distortions when the conditional mean dynamics are misspecified. We also show that the sup Wald test for breaks in the unconditional mean and variance does not have the same size distortions, yet benefits from similar power to its conditional counterpart in correctly specified models. Hence, we propose using it as an alternative and complementary test for breaks. We apply the unconditional and conditional mean and variance tests to three US series: unemployment, industrial production growth and interest rates. Both the unconditional and the conditional mean tests detect a break in the mean of interest rates. However, for the other two series, the unconditional mean test does not detect a break, while the conditional mean tests based on dynamic regression models occasionally detect a break, with the implied break-point estimator varying across different dynamic specifications. For all series, the unconditional variance does not detect a break while most tests for the conditional variance do detect a break which also varies across specifications.

  14. Steam line break analysis in CAREM-25 reactor

    International Nuclear Information System (INIS)

    Zanocco, Pablo; Gimenez, Marcelo O.; Vertullo, Alicia; Schlamp, Miguel A.; Garcia, Alicia E.

    2000-01-01

    The main objective of this report is to analyze the reactor response during a steam line break postulated accident with RELAP5, a plant code using a separated flow model. The steam line break caused a rapid blowdown of the secondary coolant increasing the heat removal in the steam generator. As a consequence and due to reactor features the core power is also increased. As maximum removed power in the secondary side is highly dependant on the total water volume evaporated during the accident a detailed model of feed water and outlet steam pipes is provided. Different cases are analyzed with and without feedwater system and considering the fail or success of the First Shutdown System. In all the sequences the DNBR and CPR remain above the minimum safety values established by design. Further calculations concerning depressurization ramps and steam generator feed water pumps response during depressurization are advised. (author)

  15. Steam Line Break Analysis in CAREM-25 Reactor

    International Nuclear Information System (INIS)

    Zanocco, Pablo; Gimenez, Marcelo; Vertullo, Alicia; Garcia, A; Schlamp, Miguel

    2000-01-01

    The main objective of this report is to analyze the reactor response during a steam line break postulated accident with RELAP5, a plant code using a separated flow model.The steam line break caused a rapid blowdown of the secondary coolant increasing the heat removal in the steam generator.As a consequence and due to reactor features the core power is also increased.As maximum removed power in the secondary side is highly dependant on the total water volume evaporated during the accident a detailed model of feed water and outlet steam pipes is provided.Different cases are analyzed with and without feedwater system and considering the fail or success of the First Shutdown System.In all the sequences the DNBR and CPR remain above the minimum safety values established by design.Further calculations concerning depressurization ramps and steam generator feed water pumps response during depressurization are advised

  16. Modelling and testing the molecular mechanism of radiation-induced chromatid breaks

    International Nuclear Information System (INIS)

    Bryant, P. E.

    2001-01-01

    Chromatid breaks induced by ionizing radiation in the G2 phase of the cell cycle are considered as markers of individual human radiosensitivity and may indicate the presence of low-penetrance genes regulating susceptibility to breast and other cancers). Together with our own study of Scottish (Tayside) breast cancer patients and a group of normal controls these studies show an overall 10-fold variation in chromatid break frequency (the parameter defining individual chromosomal 'radiosensitivity'). Thus, an understanding of the mechanisms and genes involved in determining these widely different responses should help to clarify the reasons for individual radiosensitivity and may lead us to identify key genes involved in cancer susceptibility. The presence of colour-switches at around 16% of chromatid break points (detected in harlequin-stained chromosomes) indicates that this type of chromatid break is formed by a chromatin rearrangement involving one or more large chromatin domains of the order of 3 - 5 Mbp, possibly representing transcription 'factories'. The signal model of chromatid breaks assumes that all chromatid breaks are the result of chromatin rearrangements, and that the initiating DNA double-strand break (dsb) is itself not involved in the rearrangement but signals its presence (possibly via ATM protein or DNAPK) leading to the initiation of the chromatin rearrangement. Experimental evidence from radiosensitive cell lines (e.g. human AT and hamster irs2) and with the nucleoside analogue araA (9-β-D-arabinofuranosyladenine) demonstrates the lack of correspondence between the rejoining kinetics of dsb and that of disappearance of chromatid breaks, thus supporting the signal model. Coupled with the linear induction of chromatid breaks with dose in both human and rodent cell lines of various types, and the production of chromatid breaks by single dsb in genetically engineered cell lines the classical 'breakage-first' model of chromatid breaks is no longer

  17. Paramedic rapid sequence induction (RSI) in a South African ...

    African Journals Online (AJOL)

    Methods. We undertook a retrospective observational study of paramedic RSI performed by an emergency medical service, between 12 December 2009 and 12 December 2011. Results. Eighty-six RSIs were performed during the study period. No failed intubations were reported. Heart rate was significantly reduced from a ...

  18. The production and repair of double strand breaks in cells from normal humans and patients with ataxia telangiectasia

    International Nuclear Information System (INIS)

    Lehman, A.R.; Stevens, S.

    1977-01-01

    The production and repair of double strand breaks induced by γ-rays in the DNA of human fibroblasts have been measured by sedimentation in sucrose gradients under non-denaturing conditions. Unirradiated DNA formed a rapidly sedimenting gel. Low doses of radiation released freely sedimenting DNA molecules from this gel. Higher doses reduced the rate of sedimentation of the free DNA due to the introduction of double strand breaks. The breakage efficiency was 1 break/1.3x10 10 daltons of DNA/krad. Postirradiation incubation after a high dose of radiation resulted in an increase in molecular weight of the free DNA molecules, and after a low dose the rapidly-sedimenting gel was reformed. These data suggest that double strand breaks are repaired in human fibroblasts. No significant differences were found between fibroblasts from two normal donors and four patients with the radiosensitive disorder, ataxia telangiectasia, in either the production or repair of double strand breaks

  19. Symmetry breaking in gauge glasses

    International Nuclear Information System (INIS)

    Hansen, K.

    1988-09-01

    In order to explain why nature selects the gauge groups of the Standard Model, Brene and Nielsen have proposed a way to break gauge symmetry which does not rely on the existence of a Higgs field. The observed gauge groups will in this scheme appear as the only surviving ones when this mechanism is applied to a random selection of gauge groups. The essential assumption is a discrete space-time with random couplings. Some working assumptions were made for computational reasons of which the most important is that quantum fluctuations were neclected. This work presents an example which under the same conditions show that a much wider class of groups than predicted by Brene and Nielsen will be broken. In particular no possible Standard Model Group survives unbroken. Numerical calculations support the analytical result. (orig.)

  20. Rotational Symmetry Breaking in Baby Skyrme Models

    Science.gov (United States)

    Karliner, Marek; Hen, Itay

    We discuss one of the most interesting phenomena exhibited by baby skyrmions - breaking of rotational symmetry. The topics we will deal with here include the appearance of rotational symmetry breaking in the static solutions of baby Skyrme models, both in flat as well as in curved spaces, the zero-temperature crystalline structure of baby skyrmions, and finally, the appearance of spontaneous breaking of rotational symmetry in rotating baby skyrmions.

  1. Big break for charge symmetry

    Energy Technology Data Exchange (ETDEWEB)

    Miller, G.A. [Department of Physics, University of Washington, Seattle (United States); Kolck, U. van [Department of Physics, University of Arizona, Tucson (United States)

    2003-06-01

    Two new experiments have detected charge-symmetry breaking, the mechanism responsible for protons and neutrons having different masses. Symmetry is a crucial concept in the theories that describe the subatomic world because it has an intimate connection with the laws of conservation. The theory of the strong interaction between quarks - quantum chromodynamics - is approximately invariant under what is called charge symmetry. In other words, if we swap an up quark for a down quark, then the strong interaction will look almost the same. This symmetry is related to the concept of {sup i}sospin{sup ,} and is not the same as charge conjugation (in which a particle is replaced by its antiparticle). Charge symmetry is broken by the competition between two different effects. The first is the small difference in mass between up and down quarks, which is about 200 times less than the mass of the proton. The second is their different electric charges. The up quark has a charge of +2/3 in units of the proton charge, while the down quark has a negative charge of -1/3. If charge symmetry was exact, the proton and the neutron would have the same mass and they would both be electrically neutral. This is because the proton is made of two up quarks and a down quark, while the neutron comprises two downs and an up. Replacing up quarks with down quarks, and vice versa, therefore transforms a proton into a neutron. Charge-symmetry breaking causes the neutron to be about 0.1% heavier than the proton because the down quark is slightly heavier than the up quark. Physicists had already elucidated certain aspects of charge-symmetry breaking, but our spirits were raised greatly when we heard of the recent work of Allena Opper of Ohio University in the US and co-workers at the TRIUMF laboratory in British Columbia, Canada. Her team has been trying to observe a small charge-symmetry-breaking effect for several years, using neutron beams at the TRIUMF accelerator. The researchers studied the

  2. Inductive dielectric analyzer

    International Nuclear Information System (INIS)

    Agranovich, Daniel; Popov, Ivan; Ben Ishai, Paul; Feldman, Yuri; Polygalov, Eugene

    2017-01-01

    One of the approaches to bypass the problem of electrode polarization in dielectric measurements is the free electrode method. The advantage of this technique is that, the probing electric field in the material is not supplied by contact electrodes, but rather by electromagnetic induction. We have designed an inductive dielectric analyzer based on a sensor comprising two concentric toroidal coils. In this work, we present an analytic derivation of the relationship between the impedance measured by the sensor and the complex dielectric permittivity of the sample. The obtained relationship was successfully employed to measure the dielectric permittivity and conductivity of various alcohols and aqueous salt solutions. (paper)

  3. Rock breaking methods to replace blasting

    Science.gov (United States)

    Zhou, Huisheng; Xie, Xinghua; Feng, Yuqing

    2018-03-01

    The method of breaking rock by blasting has a high efficiency and the cost is relatively low, but the associated vibration, flyrock, production of toxic gases since the 1970’s, the Western developed countries began to study the safety of breaking rock. This paper introduces different methods and their progress to safely break rock. Ideally, safe rock breaking would have little vibration, no fly stone, and no toxic gases, which can be widely used in municipal engineering, road excavation, high-risk mining, quarrying and complex environment.

  4. NPP Krsko small break LOCA analysis

    International Nuclear Information System (INIS)

    Mavko, B.; Petelin, S.; Peterlin, G.

    1987-01-01

    Parametric analysis of small break loss of coolant accident for the Krsko NPP was calculated by using RELAP5/MOD1 computer code. The model that was used in our calculations has been improved over several years and was previously tested in simulation (s) of start-up tests and known NPP Krsko transients. In our calculations we modelled automatic actions initiated by control, safety and protection systems. We also modelled the required operator actions as specified in emergency operating instructions. In small-break LOCA calculations, we varied break sizes in the cold leg. The influence of steam generator tube plugging on small break LOCA accidents was also analysed. (author)

  5. Give me a better break: Choosing workday break activities to maximize resource recovery.

    Science.gov (United States)

    Hunter, Emily M; Wu, Cindy

    2016-02-01

    Surprisingly little research investigates employee breaks at work, and even less research provides prescriptive suggestions for better workday breaks in terms of when, where, and how break activities are most beneficial. Based on the effort-recovery model and using experience sampling methodology, we examined the characteristics of employee workday breaks with 95 employees across 5 workdays. In addition, we examined resources as a mediator between break characteristics and well-being. Multilevel analysis results indicated that activities that were preferred and earlier in the work shift related to more resource recovery following the break. We also found that resources mediated the influence of preferred break activities and time of break on health symptoms and that resource recovery benefited person-level outcomes of emotional exhaustion, job satisfaction, and organizational citizenship behavior. Finally, break length interacted with the number of breaks per day such that longer breaks and frequent short breaks were associated with more resources than infrequent short breaks. (c) 2016 APA, all rights reserved).

  6. In vivo formation and repair of DNA double-strand breaks after computed tomography examinations

    OpenAIRE

    Löbrich, Markus; Rief, Nicole; Kühne, Martin; Heckmann, Martina; Fleckenstein, Jochen; Rübe, Christian; Uder, Michael

    2005-01-01

    Ionizing radiation can lead to a variety of deleterious effects in humans, most importantly to the induction of cancer. DNA double-strand breaks (DSBs) are among the most significant genetic lesions introduced by ionizing radiation that can initiate carcinogenesis. We have enumerated γ-H2AX foci as a measure for DSBs in lymphocytes from individuals undergoing computed tomography examination of the thorax and/or the abdomen. The number of DSBs induced by computed tomography examination was fou...

  7. Break-down stage in a 20 kV coaxial gun

    International Nuclear Information System (INIS)

    Feugeas, J.; Massa, M.; VonPamel, O.

    1984-01-01

    The electrical break-down of hydrogen in a coaxial electrode system (similar to Mather-type Plasma Focus) was studied for a wide range of pressures. A squirrel's cage outer electrode (cathode) of 50 mm of diameter was used to allow lateral views of the discharge, with an inner electrode (anode) of 17 mm of diameter and a pyrex sleeve of 25 mm length as insulator located at the breech of the gun. A low inductance plane plate transmission line was discharged (20 kV) through a spark gap switch over the system, with a typical peak current of 22 kA, reached after 80 ns from onset of the discharge. The fine structure of the luminous current sheath was studied by frontal and lateral open shutter photographs and by monitoring the current distribution along and across the electrodes gap. The authors tests determine the relative importance of the resistivity related to particle collision effects (αiota) and of the inductive resistivity (α L-center dot) during the break-down stage (iota=length of break-down path, L=inductance)

  8. Lie-algebra approach to symmetry breaking

    International Nuclear Information System (INIS)

    Anderson, J.T.

    1981-01-01

    A formal Lie-algebra approach to symmetry breaking is studied in an attempt to reduce the arbitrariness of Lagrangian (Hamiltonian) models which include several free parameters and/or ad hoc symmetry groups. From Lie algebra it is shown that the unbroken Lagrangian vacuum symmetry can be identified from a linear function of integers which are Cartan matrix elements. In broken symmetry if the breaking operators form an algebra then the breaking symmetry (or symmetries) can be identified from linear functions of integers characteristic of the breaking symmetries. The results are applied to the Dirac Hamiltonian of a sum of flavored fermions and colored bosons in the absence of dynamical symmetry breaking. In the partially reduced quadratic Hamiltonian the breaking-operator functions are shown to consist of terms of order g 2 , g, and g 0 in the color coupling constants and identified with strong (boson-boson), medium strong (boson-fermion), and fine-structure (fermion-fermion) interactions. The breaking operators include a boson helicity operator in addition to the familiar fermion helicity and ''spin-orbit'' terms. Within the broken vacuum defined by the conventional formalism, the field divergence yields a gauge which is a linear function of Cartan matrix integers and which specifies the vacuum symmetry. We find that the vacuum symmetry is chiral SU(3) x SU(3) and the axial-vector-current divergence gives a PCAC -like function of the Cartan matrix integers which reduces to PCAC for SU(2) x SU(2) breaking. For the mass spectra of the nonets J/sup P/ = 0 - ,1/2 + ,1 - the integer runs through the sequence 3,0,-1,-2, which indicates that the breaking subgroups are the simple Lie groups. Exact axial-vector-current conservation indicates a breaking sum rule which generates octet enhancement. Finally, the second-order breaking terms are obtained from the second-order spin tensor sum of the completely reduced quartic Hamiltonian

  9. Modeling Induction Motor Imbalances

    DEFF Research Database (Denmark)

    Armah, Kabenla; Jouffroy, Jerome; Duggen, Lars

    2016-01-01

    This paper gives a study into the development of a generalized model for a three-phase induction motor that offers flexibility of simulating balanced and unbalanced parameter scenarios. By analyzing the interaction of forces within the motor, we achieve our main objective of deriving the system d...

  10. On the linearity of the dose-effect relationship of DNA double strand breaks

    International Nuclear Information System (INIS)

    Chadwick, K.H.; Leenhouts, H.P.

    1994-01-01

    Most radiation biologists believe that DNA double-strand breaks are induced linearly with radiation dose for all types of radiation. Since 1985, with the advent of elution and gel electrophoresis techniques which permit the measurement of DNA double-strand breaks induced in mammalian cells at doses having radiobiological relevance, the true nature of the dose-effect relationship has been brought into some doubt. Many investigators measured curvilinear dose-effect relationships and a few found good correlations between the induction of the DNA double-strand breaks and cell survival. We approach the problem pragmatically by assuming that the induction of DNA double-strand breaks by 125 I Auger electron emitters incorporated into the DNA of the cells is a linear function of the number of 125 I decays, and by comparing the dose-effect relationship for sparsely ionizing radiation against this standard. The conclusion drawn that the curvilinear dose-effect relationships and the correlations with survival are real. (Author)

  11. High current induction linacs

    International Nuclear Information System (INIS)

    Barletta, W.; Faltens, A.; Henestroza, E.; Lee, E.

    1994-07-01

    Induction linacs are among the most powerful accelerators in existence. They have accelerated electron bunches of several kiloamperes, and are being investigated as drivers for heavy ion driven inertial confinement fusion (HIF), which requires peak beam currents of kiloamperes and average beam powers of some tens of megawatts. The requirement for waste transmutation with an 800 MeV proton or deuteron beam with an average current of 50 mA and an average power of 40 MW lies midway between the electron machines and the heavy ion machines in overall difficulty. Much of the technology and understanding of beam physics carries over from the previous machines to the new requirements. The induction linac allows use of a very large beam aperture, which may turn out to be crucial to reducing beam loss and machine activation from the beam halo. The major issues addressed here are transport of high intensity beams, availability of sources, efficiency of acceleration, and the state of the needed technology for the waste treatment application. Because of the transformer-like action of an induction core and the accompanying magnetizing current, induction linacs make the most economic sense and have the highest efficiencies with large beam currents. Based on present understanding of beam transport limits, induction core magnetizing current requirements, and pulse modulators, the efficiencies could be very high. The study of beam transport at high intensities has been the major activity of the HIF community. Beam transport and sources are limiting at low energies but are not significant constraints at the higher energies. As will be shown, the proton beams will be space-charge-dominated, for which the emittance has only a minor effect on the overall beam diameter but does determine the density falloff at the beam edge

  12. Nick translation detection in situ of cellular DNA strand break induced by radiation

    International Nuclear Information System (INIS)

    Maehara, Y.; Anai, H.; Kusumoto, T.; Sakaguchi, Y.; Sugimachi, K.

    1989-01-01

    DNA strand break in HeLa cells induced by radiation was detected using the in situ nick translation method. The cells were exposed to radiation of 3, 6, 12, 18, and 24 Gy in Lab-Tek tissue culture chamber/slides and were fixed with ethanol/acetic acid on the slide glass. The break sites in DNA were translated artificially in the presence of Escherichia coli DNA polymerase I and [ 3 H]-labeled dTTP. Autoradiographic observation was made of the level of break sites in the DNA. The DNA strand break appeared even with a 3 Gy exposure, increased 8.6 times at 24 Gy compared with the control cells, and this level correlated reciprocally to change in cell viability. This nick translation method provides a rapid in situ assay for determining radiation-induced DNA damage of cultured cells, in a semi-quantitative manner

  13. Caffeine impairs resection during DNA break repair by reducing the levels of nucleases Sae2 and Dna2

    Science.gov (United States)

    Tsabar, Michael; Eapen, Vinay V.; Mason, Jennifer M.; Memisoglu, Gonen; Waterman, David P.; Long, Marcus J.; Bishop, Douglas K.; Haber, James E.

    2015-01-01

    In response to chromosomal double-strand breaks (DSBs), eukaryotic cells activate the DNA damage checkpoint, which is orchestrated by the PI3 kinase-like protein kinases ATR and ATM (Mec1 and Tel1 in budding yeast). Following DSB formation, Mec1 and Tel1 phosphorylate histone H2A on serine 129 (known as γ-H2AX). We used caffeine to inhibit the checkpoint kinases after DSB induction. We show that prolonged phosphorylation of H2A-S129 does not require continuous Mec1 and Tel1 activity. Unexpectedly, caffeine treatment impaired homologous recombination by inhibiting 5′ to 3′ end resection, independent of Mec1 and Tel1 inhibition. Caffeine treatment led to the rapid loss, by proteasomal degradation, of both Sae2, a nuclease that plays a role in early steps of resection, and Dna2, a nuclease that facilitates one of two extensive resection pathways. Sae2's instability is evident in the absence of DNA damage. A similar loss is seen when protein synthesis is inhibited by cycloheximide. Caffeine treatment had similar effects on irradiated HeLa cells, blocking the formation of RPA and Rad51 foci that depend on 5′ to 3′ resection of broken chromosome ends. Our findings provide insight toward the use of caffeine as a DNA damage-sensitizing agent in cancer cells. PMID:26019182

  14. Controlling break-the-glass through alignment

    NARCIS (Netherlands)

    Adriansyah, A.; Dongen, van B.F.; Zannone, N.

    2013-01-01

    Modern IT systems have to deal with unpredictable situations and exceptions more and more often. In contrast, security mechanisms are usually very rigid. Functionality like break-the-glass is thus employed to allow users to bypass security mechanisms in case of emergencies. However, break-the-glass

  15. Charge-symmetry-breaking nucleon form factors

    Energy Technology Data Exchange (ETDEWEB)

    Kubis, Bastian, E-mail: kubis@hiskp.uni-bonn.de [Universitaet Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik (Theorie) and Bethe Center for Theoretical Physics (Germany)

    2011-11-15

    A quantitative understanding of charge-symmetry breaking is an increasingly important ingredient for the extraction of the nucleon's strange vector form factors. We review the theoretical understanding of the charge-symmetry-breaking form factors, both for single nucleons and for {sup 4}He.

  16. Charge-symmetry-breaking nucleon form factors

    International Nuclear Information System (INIS)

    Kubis, Bastian

    2011-01-01

    A quantitative understanding of charge-symmetry breaking is an increasingly important ingredient for the extraction of the nucleon’s strange vector form factors. We review the theoretical understanding of the charge-symmetry-breaking form factors, both for single nucleons and for 4 He.

  17. Breaking antidunes: Cyclic behavior due to hysteresis

    DEFF Research Database (Denmark)

    Deigaard, Rolf

    2006-01-01

    The cyclic behavior of breaking antidunes (growth, breaking of surface wave, obliteration) is investigated by use of a numerical model. The model includes the transition between supercritical and transcritical flow. As the antidune grows the flow becomes transcritical and a hydraulic jump is form...

  18. Metastable Supersymmetry Breaking in a Cooling Universe

    International Nuclear Information System (INIS)

    Kaplunovsky, Vadim S.

    2007-01-01

    I put metastable supersymmetry breaking in a cosmological context. I argue that under reasonable assumptions, the cooling down early Universe favors metastable SUSY-breaking vacua over the stable supersymmetric vacua. To illustrate the general argument, I analyze the early-Universe history of the Intriligator-Seiberg-Shih model

  19. The new break-even analysis.

    Science.gov (United States)

    Laskaris, James; Regan, Katie

    2013-12-01

    Changes in the economic and legislative environment have complicated the capital acquisition landscape. Hospitals and health systems should: Question the assumptions that underlie their break-even analysis. Revamp the break-even calculator. Engage in discussions about the clinical aspects of equipment and technology acquisition decisions.

  20. Strongly coupled semidirect mediation of supersymmetry breaking

    International Nuclear Information System (INIS)

    Ibe, M.; Izawa, K.-I.; Nakai, Y.

    2009-01-01

    Strongly coupled semidirect gauge mediation models of supersymmetry breaking through massive mediators with standard-model charges are investigated by means of composite degrees of freedom. Sizable mediation is realized to generate the standard-model gaugino masses for a small mediator mass without breaking the standard-model symmetries.

  1. Multiscale Simulation of Breaking Wave Impacts

    DEFF Research Database (Denmark)

    Lindberg, Ole

    compare reasonably well. The incompressible and inviscid ALE-WLS model is coupled with the potential flow model of Engsig-Karup et al. [2009], to perform multiscale calculation of breaking wave impacts on a vertical breakwater. The potential flow model provides accurate calculation of the wave...... with a potential flow model to provide multiscale calculation of forces from breaking wave impacts on structures....

  2. Dynamical study of symmetries: breaking and restauration

    International Nuclear Information System (INIS)

    Schuck, P.

    1986-09-01

    First symmetry breaking (spontaneous) is explained and the physical implication discussed for infinite systems. The relation with phase transitions is indicated. Then the specific aspects of symmetry breaking in finite systems is treated and illustrated in detail for the case of translational invariance with the help of an oversimplified but exactly solvable model. The method of projection (restauration of symmetry) is explained for the static case and also applied to the model. Symmetry breaking in the dynamical case and for instance the notion of a soft mode responsible for the symmetry breaking is discussed in the case of superfluidity and another exactly solvable model is introduced. The Goldstone mode is treated in detail. Some remarks on analogies with the breaking of chiral symmetry are made. Some recent developments in the theory of symmetry restauration are briefly outlined [fr

  3. Chiral symmetry and chiral-symmetry breaking

    International Nuclear Information System (INIS)

    Peskin, M.E.

    1982-12-01

    These lectures concern the dynamics of fermions in strong interaction with gauge fields. Systems of fermions coupled by gauge forces have a very rich structure of global symmetries, which are called chiral symmetries. These lectures will focus on the realization of chiral symmetries and the causes and consequences of thier spontaneous breaking. A brief introduction to the basic formalism and concepts of chiral symmetry breaking is given, then some explicit calculations of chiral symmetry breaking in gauge theories are given, treating first parity-invariant and then chiral models. These calculations are meant to be illustrative rather than accurate; they make use of unjustified mathematical approximations which serve to make the physics more clear. Some formal constraints on chiral symmetry breaking are discussed which illuminate and extend the results of our more explicit analysis. Finally, a brief review of the phenomenological theory of chiral symmetry breaking is presented, and some applications of this theory to problems in weak-interaction physics are discussed

  4. Dating breaks for global crude oil prices and their volatility : a possible price band for global crude prices

    International Nuclear Information System (INIS)

    Liao, H.C.; Suen, Y.B.

    2006-01-01

    Global oil prices are among the most visible of all historical commodity records. This paper presented and applied the multiple structural change method developed by Baie and Perron (BP) to investigate daily West Texas Intermediate (WTI) spot prices from January 2, 1986 to December 30, 2004 as collected by the United States Department of Energy. In particular, the BP statistical method was used to estimate the number and location of structural breaks in global oil price series and their volatility. The objective was to precisely determine the exact structural break in the global oil market. The breaks for both the price of oil and its volatility were successfully located and dated. It was shown that the break for the structural change in oil prices occurred on November 12, 1999, where the average oil price was U$19.02 per barrel previously, and U$30.90 afterwards. Two breaks for oil price volatility were also found, the first in March 1991 and the other in December 1995. The volatility was measured in 3 regimes by dividing these 2 breaks. It was suggested that since oil prices increased more rapidly during the second half of 2004 and 2005, it is possible that another structural break may be found during this period. However, it wa cautioned that it is difficult to find another significant break until more data becomes available, particularly for periods characterized by a rapid increase in price. 24 refs., 5 tabs., 2 figs

  5. Broadband illumination of superconducting pair breaking photon detectors

    International Nuclear Information System (INIS)

    Guruswamy, T; Goldie, D J; Withington, S

    2016-01-01

    Understanding the detailed behaviour of superconducting pair breaking photon detectors such as Kinetic Inductance Detectors (KIDs) requires knowledge of the nonequilibrium quasiparticle energy distributions. We have previously calculated the steady state distributions resulting from uniform absorption of monochromatic sub gap and above gap frequency radiation by thin films. In this work, we use the same methods to calculate the effect of illumination by broadband sources, such as thermal radiation from astrophysical phenomena or from the readout system. Absorption of photons at multiple above gap frequencies is shown to leave unchanged the structure of the quasiparticle energy distribution close to the superconducting gap. Hence for typical absorbed powers, we find the effects of absorption of broadband pair breaking radiation can simply be considered as the sum of the effects of absorption of many monochromatic sources. Distribution averaged quantities, like quasiparticle generation efficiency η, match exactly a weighted average over the bandwidth of the source of calculations assuming a monochromatic source. For sub gap frequencies, however, distributing the absorbed power across multiple frequencies does change the low energy quasiparticle distribution. For moderate and high absorbed powers, this results in a significantly larger η–a higher number of excess quasiparticles for a broadband source compared to a monochromatic source of equal total absorbed power. Typically in KIDs the microwave power absorbed has a very narrow bandwidth, but in devices with broad resonance characteristics (low quality factors), this increase in η may be measurable. (paper)

  6. Big break for charge symmetry

    CERN Document Server

    Miller, G A

    2003-01-01

    Two new experiments have detected charge-symmetry breaking, the mechanism responsible for protons and neutrons having different masses. Symmetry is a crucial concept in the theories that describe the subatomic world because it has an intimate connection with the laws of conservation. The theory of the strong interaction between quarks - quantum chromodynamics - is approximately invariant under what is called charge symmetry. In other words, if we swap an up quark for a down quark, then the strong interaction will look almost the same. This symmetry is related to the concept of sup i sospin sup , and is not the same as charge conjugation (in which a particle is replaced by its antiparticle). Charge symmetry is broken by the competition between two different effects. The first is the small difference in mass between up and down quarks, which is about 200 times less than the mass of the proton. The second is their different electric charges. The up quark has a charge of +2/3 in units of the proton charge, while ...

  7. Inductive Communication System Design Summary

    Science.gov (United States)

    1978-09-01

    The report documents the experience obtained during the design and development of the Inductive Communications System used in the Morgantown People Mover. The Inductive Communications System is used to provide wayside-to-vehicle and vehicle-to-waysid...

  8. lambda. -prophage induction in repair-deficient and wild type E. coli strains by. gamma. -rays and heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Bonev, M.N.; Kozubek, S.; Krasavin, E.A.; Amirtajev, K.G. (Joint Inst. for Nuclear Research, Dubna (USSR))

    1990-05-01

    {lambda}-prophage induction in repair-deficient and wild-type E. coli strains by heavy ions and {gamma}-rays was investigated. The dose dependence of the fraction of induced cells has been measured and its initial slope ({lambda}-induction potency) determined. Induction by {gamma}-rays was found to be more efficient in a polA-repair-deficient strain; the value of {lambda}-induction potency is zero in lexA{sup -} and recA{sup -} strains. The {lambda}-induction potency potency increased with LET for wild-type cells but remained constant in polA{sup -} mutant cells. It is suggested that DNA damage triggering the {lambda}-prophage induction in the case of ionizing radiation could be a type of DNA single-strand break with complex structures which cannot be repaired by fast repair processes, and requires a substantial level of energy deposition for induction in a DNA molecule. (author).

  9. Application of Laser Micro-irradiation for Examination of Single and Double Strand Break Repair in Mammalian Cells.

    Science.gov (United States)

    Holton, Nathaniel W; Andrews, Joel F; Gassman, Natalie R

    2017-09-05

    Highly coordinated DNA repair pathways exist to detect, excise and replace damaged DNA bases, and coordinate repair of DNA strand breaks. While molecular biology techniques have clarified structure, enzymatic functions, and kinetics of repair proteins, there is still a need to understand how repair is coordinated within the nucleus. Laser micro-irradiation offers a powerful tool for inducing DNA damage and monitoring the recruitment of repair proteins. Induction of DNA damage by laser micro-irradiation can occur with a range of wavelengths, and users can reliably induce single strand breaks, base lesions and double strand breaks with a range of doses. Here, laser micro-irradiation is used to examine repair of single and double strand breaks induced by two common confocal laser wavelengths, 355 nm and 405 nm. Further, proper characterization of the applied laser dose for inducing specific damage mixtures is described, so users can reproducibly perform laser micro-irradiation data acquisition and analysis.

  10. Improving long term driving comfort by taking breaks - How break activity affects effectiveness.

    Science.gov (United States)

    Sammonds, George M; Mansfield, Neil J; Fray, Mike

    2017-11-01

    During long duration journeys, drivers are encouraged to take regular breaks. The benefits of breaks have been documented for safety; breaks may also be beneficial for comfort. The activity undertaken during a break may influence its effectiveness. Volunteers completed 3 journeys on a driving simulator. Each 130 min journey included a 10 min break after the first hour. During the break volunteers either stayed seated, left the simulator and sat in an adjacent room, or took a walk on a treadmill. The results show a reduction in driver discomfort during the break for all 3 conditions, but the effectiveness of the break was dependent on activity undertaken. Remaining seated in the vehicle provided some improvement in comfort, but more was experienced after leaving the simulator and sitting in an adjacent room. The most effective break occurred when the driver walked for 10 min on a treadmill. The benefits from taking a break continued until the end of the study (after a further hour of driving), such that comfort remained the best after taking a walk and worst for those who remained seated. It is concluded that taking a break and taking a walk is an effective method for relieving driving discomfort. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Induction technology optimization code

    International Nuclear Information System (INIS)

    Caporaso, G.J.; Brooks, A.L.; Kirbie, H.C.

    1992-01-01

    A code has been developed to evaluate relative costs of induction accelerator driver systems for relativistic klystrons. The code incorporates beam generation, transport and pulsed power system constraints to provide an integrated design tool. The code generates an injector/accelerator combination which satisfies the top level requirements and all system constraints once a small number of design choices have been specified (rise time of the injector voltage and aspect ratio of the ferrite induction cores, for example). The code calculates dimensions of accelerator mechanical assemblies and values of all electrical components. Cost factors for machined parts, raw materials and components are applied to yield a total system cost. These costs are then plotted as a function of the two design choices to enable selection of an optimum design based on various criteria. (Author) 11 refs., 3 figs

  12. Glass manufacturing through induction

    International Nuclear Information System (INIS)

    Boen, R.; Paya, B.; Roscini, M.; Fautrelle, Y.; Tuaz, F.; Delage, D.

    1991-01-01

    Oxides and glasses are electrical and thermal insulators, but show the characteristic of being weakly conductors of electricity when they are melt. It is then possible to heat them through HF induction. This interesting property allows the development of a melting process in cold crucible induction furnace. The process is being studied and developed by a consortium made up of CFEI, CEA Marcoule, ELECTRICITE DE FRANCE and MADYLAM laboratory. The studies include 2 parts: a) One experimental part to develop the technology and research for satisfying configurations, through a small size platform (10 to 30 kg/h). The long run continuous pouring melting tests made on different kinds of glass allow to go-on with industrial range units. b) One theoretical part to understand the magneto-thermo-hydraulic phenomenon hardly in relation with the heavy dependence of the physical characteristics (electrical and heat conductivities, viscosity) according to temperature. 6 refs., 4 figs [fr

  13. Inductive energy storage commutator

    International Nuclear Information System (INIS)

    Gavrilov, I.M.

    1987-01-01

    An inductive energy storage commutator is described. The value of commutated current is up to 800 A, the voltage amplitude in the load is up to 50 kV, the working frequency is equal to 1-50 Hz, the commutated power is up to 40 MW. The commutating device comprises of the first stage commutator having two in-series connected modules of the BTSV - 800/235 high-voltage thyristor unit, the second stage commutator containing three GMI-43A parallel connected powerful pulsed triodes, a commutating capacitor, an induction coil, two supplementary high-voltage thyristor keys (20 in-series connected thyristors T2-300 (13 class)), load, control pulse shapers, thyristor keys, power supply

  14. Pulse induction heating

    Energy Technology Data Exchange (ETDEWEB)

    Vasiliev, A S; Kachanov, B Y; Kogan, B V

    1993-12-31

    Induction heating and three types of pulse processes were studied. It was found that in pulse processes the frequency and pulse duration of heat treatments do not remain constant. High frequency pulse heat treatments can be used on sprayed coatings; such treatments will result in stronger surfaces with no cracks. For induction hardening, the rate of specific power was 1 to 1.5 kW/sq.cm, for forging it was 0.2 to 0.3 kW/sq.cm and for melting it was 0.05 to 0.1 kW/sq.cm. The application of pulse heating will result in higher rates of specific power.

  15. Inductive Reasoning: A Training Approach

    Science.gov (United States)

    Klauer, Karl Josef; Phye, Gary D.

    2008-01-01

    Researchers have examined inductive reasoning to identify different cognitive processes when participants deal with inductive problems. This article presents a prescriptive theory of inductive reasoning that identifies cognitive processing using a procedural strategy for making comparisons. It is hypothesized that training in the use of the…

  16. Lexicographic Path Induction

    DEFF Research Database (Denmark)

    Schürmann, Carsten; Sarnat, Jeffrey

    2009-01-01

    Programming languages theory is full of problems that reduce to proving the consistency of a logic, such as the normalization of typed lambda-calculi, the decidability of equality in type theory, equivalence testing of traces in security, etc. Although the principle of transfinite induction......, and weak normalization for Gödel’s T follows indirectly; both have been formalized in a prototypical extension of Twelf....

  17. Diagnostics for induction accelerators

    International Nuclear Information System (INIS)

    Fessenden, T.J.

    1996-04-01

    The induction accelerator was conceived by N. C. Christofilos and first realized as the Astron accelerator that operated at LLNL from the early 1960's to the end of 1975. This accelerator generated electron beams at energies near 6 MeV with typical currents of 600 Amperes in 400 ns pulses. The Advanced Test Accelerator (ATA) built at Livermore's Site 300 produced 10,000 Ampere beams with pulse widths of 70 ns at energies approaching 50 MeV. Several other electron and ion induction accelerators have been fabricated at LLNL and LBNL. This paper reviews the principal diagnostics developed through efforts by scientists at both laboratories for measuring the current, position, energy, and emittance of beams generated by these high current, short pulse accelerators. Many of these diagnostics are closely related to those developed for other accelerators. However, the very fast and intense current pulses often require special diagnostic techniques and considerations. The physics and design of the more unique diagnostics developed for electron induction accelerators are presented and discussed in detail

  18. Diagnostics for induction accelerators

    International Nuclear Information System (INIS)

    Fessenden, T.J.

    1997-01-01

    The induction accelerator was conceived by N. C. Christofilos and first realized as the Astron accelerator that operated at Lawrence Livermore National Laboratory (LLNL) from the early 1960s to the end of 1975. This accelerator generated electron beams at energies near 6 MeV with typical currents of 600 Amperes in 400-ns pulses. The Advanced Test Accelerator (ATA) built at Livermore close-quote s Site 300 produced 10,000-Ampere beams with pulse widths of 70 ns at energies approaching 50 MeV. Several other electron and ion induction accelerators have been fabricated at LLNL and Lawrence Berkeley National Laboratory (LBNL). This paper reviews the principal diagnostics developed through efforts by scientists at both laboratories for measuring the current, position, energy, and emittance of beams generated by these high-current, short-pulse accelerators. Many of these diagnostics are closely related to those developed for other accelerators. However, the very fast and intense current pulses often require special diagnostic techniques and considerations. The physics and design of the more unique diagnostics developed for electron induction accelerators are presented and discussed in detail. copyright 1997 American Institute of Physics

  19. Science Illiteracy: Breaking the Cycle

    Science.gov (United States)

    Lebofsky, L. A.; Lebofsky, N. R.

    2003-12-01

    At the University of Arizona, as at many state universities and colleges, the introductory science classes for non-science majors may be the only science classes that future K--8 teachers will take. The design of the UA's General Education program requires all future non-science certified teachers to take the General Education science classes. These classes are therefore an ideal venue for the training of the state's future teachers. Many students, often including future teachers, are ill-prepared for college, i.e., they lack basic science content knowledge, basic mathematics skills, and reading and writing skills. They also lack basic critical thinking skills and study skills. It is within this context that our future teachers are trained. How do we break the cycle of science illiteracy? There is no simple solution, and certainly not a one-size-fits-all panacea that complements every professor's style of instruction. However, there are several programs at the University of Arizona, and also principles that I apply in my own classes, that may be adaptable in other classrooms. Assessment of K--12 students' learning supports the use of inquiry-based science instruction. This approach can be incorporated in college classes. Modeling proven and productive teaching methods for the future teachers provides far more than ``just the facts,'' and all students gain from the inquiry approach. Providing authentic research opportunities employs an inquiry-based approach. Reading (outside the textbook) and writing provide feedback to students with poor writing and critical thinking skills. Using peer tutors and an instant messaging hot line gives experience to the tutors and offers "comfortable" assistance to students.

  20. Dynamical Symmetry Breaking of Extended Gauge Symmetries

    OpenAIRE

    Appelquist, Thomas; Shrock, Robert

    2003-01-01

    We construct asymptotically free gauge theories exhibiting dynamical breaking of the left-right, strong-electroweak gauge group $G_{LR} = {\\rm SU}(3)_c \\times {\\rm SU}(2)_L \\times {\\rm SU}(2)_R \\times {\\rm U}(1)_{B-L}$, and its extension to the Pati-Salam gauge group $G_{422}={\\rm SU}(4)_{PS} \\times {\\rm SU}(2)_L \\times {\\rm SU}(2)_R$. The models incorporate technicolor for electroweak breaking, and extended technicolor for the breaking of $G_{LR}$ and $G_{422}$ and the generation of fermion ...

  1. Spontaneous symmetry breaking and its cosmological consequences

    International Nuclear Information System (INIS)

    Kobzarev, I.Yu.

    1975-01-01

    The concept of symmetry and of the spontaneous symmetry breaking are presented in popular form as applied to quantum physics. Though the presence of the spontaneous symmetry breaking is not proved directly for interactions of elementary particles, on considering the hypothesis of its presence as applied to the hot Universe theory a possibility of obtaining rather uncommon cosmological consequences is discussed. In particular, spontaneous symmetry breaking of vacuum and the rather hot Universe lead necessarily to the presence of the domain structure of the Universe with the surfase energy at the domain interface in the form of a real physical object

  2. Supersymmetry Breaking through Transparent Extra Dimensions

    Energy Technology Data Exchange (ETDEWEB)

    Schmaltz, Martin

    1999-11-23

    We propose a new framework for mediating supersymmetry breaking through an extra dimension. It predicts positive scalar masses and solves the supersymmetric flavor problem. Supersymmetry breaks on a ''source'' brane that is spatially separated from a parallel brane on which the standard model matter fields and their superpartners live. The gauge and gaugino fields propagate in the bulk, the latter receiving a supersymmetry breaking mass from direct couplings to the source brane. Scalar masses are suppressed at the high scale but are generated via the renormalization group. We briefly discuss the spectrum and collider signals for a range of compactification scales.

  3. Effect of caffeine on the ultraviolet light induction of SV40 virus from transformed hamster cells

    International Nuclear Information System (INIS)

    Zamansky, G.B.; Kleinman, L.F.; Little, J.B.; Black, P.H.; Kaplan, J.C.

    1976-01-01

    The effect of caffeine on the uv light induction of SV40 virus from two transformed hamster cell lines heterogeneous for the induction of infectious virus was studied. The amount of virus induced was significantly increased in both cell lines when exposure to uv light was followed by treatment with caffeine. Caffeine in the absence of uv irradiation did not stimulate virus induction, nor did it stimulate SV40 replication in a lytic infection. There was an apparent difference in the concentrations of caffeine which maximally stimulated SV40 virus induction in the two cell lines. This effect could not be explained by differences in cell survival after exposure to uv light and caffeine. Since caffeine is known to cause the accumulation of gaps formed in DNA during postreplication repair of uv-irradiated rodent cells, our results support the hypothesis that the formation of gaps or breaks in DNA is an important early step in virus induction

  4. Binding of Multiple Rap1 Proteins Stimulates Chromosome Breakage Induction during DNA Replication.

    Directory of Open Access Journals (Sweden)

    Greicy H Goto

    2015-08-01

    Full Text Available Telomeres, the ends of linear eukaryotic chromosomes, have a specialized chromatin structure that provides a stable chromosomal terminus. In budding yeast Rap1 protein binds to telomeric TG repeat and negatively regulates telomere length. Here we show that binding of multiple Rap1 proteins stimulates DNA double-stranded break (DSB induction at both telomeric and non-telomeric regions. Consistent with the role of DSB induction, Rap1 stimulates nearby recombination events in a dosage-dependent manner. Rap1 recruits Rif1 and Rif2 to telomeres, but neither Rif1 nor Rif2 is required for DSB induction. Rap1-mediated DSB induction involves replication fork progression but inactivation of checkpoint kinase Mec1 does not affect DSB induction. Rap1 tethering shortens artificially elongated telomeres in parallel with telomerase inhibition, and this telomere shortening does not require homologous recombination. These results suggest that Rap1 contributes to telomere homeostasis by promoting chromosome breakage.

  5. Inductive reasoning 2.0.

    Science.gov (United States)

    Hayes, Brett K; Heit, Evan

    2018-05-01

    Inductive reasoning entails using existing knowledge to make predictions about novel cases. The first part of this review summarizes key inductive phenomena and critically evaluates theories of induction. We highlight recent theoretical advances, with a special emphasis on the structured statistical approach, the importance of sampling assumptions in Bayesian models, and connectionist modeling. A number of new research directions in this field are identified including comparisons of inductive and deductive reasoning, the identification of common core processes in induction and memory tasks and induction involving category uncertainty. The implications of induction research for areas as diverse as complex decision-making and fear generalization are discussed. This article is categorized under: Psychology > Reasoning and Decision Making Psychology > Learning. © 2017 Wiley Periodicals, Inc.

  6. A taxonomy of inductive problems.

    Science.gov (United States)

    Kemp, Charles; Jern, Alan

    2014-02-01

    Inductive inferences about objects, features, categories, and relations have been studied for many years, but there are few attempts to chart the range of inductive problems that humans are able to solve. We present a taxonomy of inductive problems that helps to clarify the relationships between familiar inductive problems such as generalization, categorization, and identification, and that introduces new inductive problems for psychological investigation. Our taxonomy is founded on the idea that semantic knowledge is organized into systems of objects, features, categories, and relations, and we attempt to characterize all of the inductive problems that can arise when these systems are partially observed. Recent studies have begun to address some of the new problems in our taxonomy, and future work should aim to develop unified theories of inductive reasoning that explain how people solve all of the problems in the taxonomy.

  7. Repair of the double-strand breaks produced by /sup 125/I disintegrations in the DNA of micrococcus radiodurans

    Energy Technology Data Exchange (ETDEWEB)

    Myers, D K [Atomic Energy of Canada Ltd., Chalk River, Ontario. Chalk River Nuclear Labs.

    1978-01-01

    Wild-type M. radiodurans and two radiosensitive mutants were used to study the lethal effects of /sup 125/I disintegrations in their DNA. The relative sensitivities of these three strains to inactivation by ..gamma..-radiation were reflected in their relative sensitivities to inactivation by /sup 125/I decay. The number of double-strand (ds) breaks in the DNA appeared to be similar at levels of ..gamma..-radiation and of /sup 125/I decay that reduced survival to 10%. All three strains of M. radiodurans rapidly repaired ds breaks produced in their DNA by either ..gamma..-radiation or /sup 125/I disintegrations. If one ds break per cell is a lethal event (Krisch. et al., 1975), cells of the three strains tested would die when they had left unrepaired one ds break out of an initial 45, 600 or 1800 ds breaks per single cell.

  8. Rapid detection of DNA-interstrand and DNA-protein cross-links in mammalian cells by gravity-flow alkaline elution

    International Nuclear Information System (INIS)

    Hincks, J.R.; Coulombe, R.A. Jr.

    1989-01-01

    Alkaline elution is a sensitive and commonly used technique to detect cellular DNA damage in the form of DNA strand breaks and DNA cross-links. Conventional alkaline elution procedures have extensive equipment requirements and are tedious to perform. Our laboratory recently presented a rapid, simplified, and sensitive modification of the alkaline elution technique to detect carcinogen-induced DNA strand breaks. In the present study, we have further modified this technique to enable the rapid characterization of chemically induced DNA-interstrand and DNA-protein associated cross-links in cultured epithelial cells. Cells were exposed to three known DNA cross-linking agents, nitrogen mustard (HN 2 ), mitomycin C (MMC), or ultraviolet irradiation (UV). One hour exposures of HN 2 at 0.25, 1.0, and 4.0 microM or of MMC at 20, 40, and 60 microM produced a dose-dependent induction of total DNA cross-links by these agents. Digestion with proteinase K revealed that HN 2 and MMC induced both DNA-protein cross-links and DNA-interstrand cross-links. Ultraviolet irradiation induced both DNA cross-links and DNA strand breaks, the latter of which were either protein and nonprotein associated. The results demonstrate that gravity-flow alkaline elution is a sensitive and accurate method to characterize the molecular events of DNA cross-linking. Using this procedure, elution of DNA from treated cells is completed in 1 hr, and only three fractions per sample are analyzed. This method may be useful as a rapid screening assay for genotoxicity and/or as an adjunct to other predictive assays for potential mutagenic or carcinogenic agents

  9. Dirac neutrino masses from generalized supersymmetry breaking

    International Nuclear Information System (INIS)

    Demir, D.A.; Everett, L.L.; Langacker, P.

    2007-12-01

    We demonstrate that Dirac neutrino masses in the experimentally preferred range are generated within supersymmetric gauge extensions of the Standard Model with a generalized supersymmetry breaking sector. If the usual superpotential Yukawa couplings are forbidden by the additional gauge symmetry (such as a U(1) ' ), effective Dirac mass terms involving the ''wrong Higgs'' field can arise either at tree level due to hard supersymmetry breaking fermion Yukawa couplings, or at one-loop due to nonanalytic or ''nonholomorphic'' soft supersymmetry breaking trilinear scalar couplings. As both of these operators are naturally suppressed in generic models of supersymmetry breaking, the resulting neutrino masses are naturally in the sub-eV range. The neutrino magnetic and electric dipole moments resulting from the radiative mechanism also vanish at one-loop order. (orig.)

  10. Tidal Mixing at the Shelf Break

    National Research Council Canada - National Science Library

    Hogg, Nelson; Legg, Sonya

    2005-01-01

    The aim of this project was to study mixing forced by tidal flow over sudden changes in topographic slope such as near the shelf-break, using high-resolution nonhydrostatic numerical simulations employing the MIT gem...

  11. Higgsless grand unified theory breaking and trinification

    International Nuclear Information System (INIS)

    Carone, Christopher D.; Conroy, Justin M.

    2004-01-01

    Boundary conditions on an extra dimensional interval can be chosen to break bulk gauge symmetries and to reduce the rank of the gauge group. We consider this mechanism in models with gauge trinification. We determine the boundary conditions necessary to break the trinified gauge group directly down to that of the standard model. Working in an effective theory for the gauge-symmetry-breaking parameters on a boundary, we examine the limit in which the grand-unified theory-breaking-sector is Higgsless and show how one may obtain the low-energy particle content of the minimal supersymmetric standard model. We find that gauge unification is preserved in this scenario, and that the differential gauge coupling running is logarithmic above the scale of compactification. We compare the phenomenology of our model to that of four dimensional 'trinified' theories

  12. Water Breaking: Understand This Sign of Labor

    Science.gov (United States)

    Healthy Lifestyle Labor and delivery, postpartum care Water breaking worries? Prepare yourself for childbirth by getting the facts about this important sign of labor. By Mayo Clinic Staff If you're ...

  13. On breaks of the Indian monsoon

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    quadrapole is a basic feature of weak spells of the intraseasonal variation over the Asia-west Pacific region. ... (Earth Planet. Sci.), 112 .... be useful to define the break monsoon (and active ... monsoon zone, different scientists have used the.

  14. The problem of symmetry breaking hierarchy

    International Nuclear Information System (INIS)

    Natale, A.A.

    1983-01-01

    The problem of symmetry breaking hierarchy in grand unified theories is discussed, proving the impossibility to get a big hierarchy of interactions, in a natural way within the framework of perturbation theory. (L.C.) [pt

  15. Entropic Entanglement: Information Prison Break

    Directory of Open Access Journals (Sweden)

    Alexander Y. Yosifov

    2017-01-01

    Full Text Available We argue that certain nonviolent local quantum field theory (LQFT modification considered at the global horizon (r=2M of a static spherically symmetric black hole can lead to adiabatic leakage of quantum information in the form of Hawking particles. The source of the modification is (i smooth at r=2M and (ii rapidly vanishing at r≫2M. Furthermore, we restore the unitary evolution by introducing extra quanta which departs slightly from the generic Hawking emission without changing the experience of an infalling observer (no drama. Also, we suggest that a possible interpretation of the Bekenstein-Hawking bound as entanglement entropy may yield a nonsingular dynamical horizon behavior described by black hole thermodynamics. Hence, by treating gravity as a field theory and considering its coupling to the matter fields in the Minkowski vacuum, we derive the conjectured fluctuations of the background geometry of a black hole.

  16. Spontaneous symmetry breaking in N=3 supergravity

    International Nuclear Information System (INIS)

    Zinov'ev, Yu.M.

    1986-01-01

    The possibility of the spontaneous symmetry breaking without a cosmological term in N=3 supergravity is investigated. A new, dual version of N=3 supergravity - U(3)-supergravity is constructed. Such a theory is shown to admit a spontaneous supersymmetry breaking without a cosmological term and with three arbitrary scales, including partial super-Higgs effect N=3 → N=2 and N=3 → N=1

  17. Why and How Java Developers Break APIs

    OpenAIRE

    Brito, Aline; Xavier, Laerte; Hora, Andre; Valente, Marco Tulio

    2018-01-01

    Modern software development depends on APIs to reuse code and increase productivity. As most software systems, these libraries and frameworks also evolve, which may break existing clients. However, the main reasons to introduce breaking changes in APIs are unclear. Therefore, in this paper, we report the results of an almost 4-month long field study with the developers of 400 popular Java libraries and frameworks. We configured an infrastructure to observe all changes in these libraries and t...

  18. Lifshitz-sector mediated SUSY breaking

    OpenAIRE

    Pospelov, MaximDepartment of Physics and Astronomy, University of Victoria, Victoria, BC, V8P 5C2, Canada; Tamarit, Carlos(Perimeter Institute for Theoretical Physics, Waterloo, ON, N2L 2Y5, Canada)

    2014-01-01

    We propose a novel mechanism of SUSY breaking by coupling a Lorentz-invariant supersymmetric matter sector to non-supersymmetric gravitational interactions with Lifshitz scaling. The improved UV properties of Lifshitz propagators moderate the otherwise uncontrollable ultraviolet divergences induced by gravitational loops. This ensures that both the amount of induced Lorentz violation and SUSY breaking in the matter sector are controlled by $ {{{\\Lambda_{\\mathrm{HL}}^2}} \\left/ {{M_P^2}} \\righ...

  19. Group theory of spontaneous symmetry breaking

    International Nuclear Information System (INIS)

    Ghaboussi, F.

    1987-01-01

    The connection between the minimality of the Higgs field potential and the maximal little groups of its representation obtained by spontaneous symmetry breaking is analyzed. It is shown that for several representations the lowest minimum of the potential is related to the maximal little group of those representations. Furthermore, a practical necessity criterion is given for the representation of the Higgs field needed for spontaneous symmetry breaking

  20. Linear induction motor

    International Nuclear Information System (INIS)

    Barkman, W.E.; Adams, W.Q.; Berrier, B.R.

    1978-01-01

    A linear induction motor has been operated on a test bed with a feedback pulse resolution of 5 nm (0.2 μin). Slewing tests with this slide drive have shown positioning errors less than or equal to 33 nm (1.3 μin) at feedrates between 0 and 25.4 mm/min (0-1 ipm). A 0.86-m (34-in)-stroke linear motor is being investigated, using the SPACO machine as a test bed. Initial results were encouraging, and work is continuing to optimize the servosystem compensation

  1. The structure of GUT breaking by orbifolding

    International Nuclear Information System (INIS)

    Hebecker, Arthur; March-Russell, John

    2002-01-01

    Recently, an attractive model of GUT breaking has been proposed in which a 5-dimensional supersymmetric SU(5) gauge theory on an S 1 /(Z 2 xZ 2 ') orbifold is broken down to the 4d MSSM by SU(5)-violating boundary conditions. Motivated by this construction and several related realistic models, we investigate the general structure of orbifolds in the effective field theory context, and of this orbifold symmetry breaking mechanism in particular. An analysis of the group theoretic structure of orbifold breaking is performed. This depends upon the existence of appropriate inner and outer automorphisms of the Lie algebra, and we show that a reduction of the rank of the GUT group is possible. Some aspects of larger GUT theories based on SO(10) and E 6 are discussed. We explore the possibilities of defining the theory directly on a space with boundaries and breaking the gauge symmetry by more general consistently chosen boundary conditions for the fields. Furthermore, we derive the relation of orbifold breaking with the familiar mechanism of Wilson line breaking, finding a one-to-one correspondence, both conceptually and technically. Finally, we analyse the consistency of orbifold models in the effective field theory context, emphasizing the necessity for self-adjoint extensions of the Hamiltonian and other conserved operators, and especially the highly restrictive anomaly cancellation conditions that apply if the bulk theory lives in more than 5 dimensions

  2. The spontaneous ℤ_2 breaking Twin Higgs

    International Nuclear Information System (INIS)

    Beauchesne, Hugues; Earl, Kevin; Grégoire, Thomas

    2016-01-01

    The Twin Higgs model seeks to address the little hierarchy problem by making the Higgs a pseudo-Goldstone of a global SU(4) symmetry that is spontaneously broken to SU(3). Gauge and Yukawa couplings, which explicitly break SU(4), enjoy a discrete ℤ_2 symmetry that accidentally maintains SU(4) at the quadratic level and therefore keeps the Higgs light. Contrary to most beyond the Standard Model theories, the quadratically divergent corrections to the Higgs mass are cancelled by a mirror sector, which is uncharged under the Standard Model groups. However, the Twin Higgs with an exact ℤ_2 symmetry leads to equal vevs in the Standard Model and mirror sectors, which is phenomenologically unviable. An explicit ℤ_2 breaking potential must then be introduced and tuned against the SU(4) breaking terms to produce a hierarchy of vevs between the two sectors. This leads to a moderate but non-negligible tuning. We propose a model to alleviate this tuning, without the need for an explicit ℤ_2 breaking sector. The model consists of two SU(4) fundamental Higgses, one whose vacuum preserves ℤ_2 and one whose vacuum breaks it. As the interactions between the two Higgses are turned on, the ℤ_2 breaking is transmitted from the broken to the unbroken sector and a small hierarchy of vevs is naturally produced. The presence of an effective tadpole and feedback between the two Higgses lead to a sizable improvement of the tuning. The resulting Higgs boson is naturally very Standard Model like.

  3. Antibody induction versus corticosteroid induction for liver transplant recipients

    DEFF Research Database (Denmark)

    Penninga, Luit; Wettergren, André; Wilson, Colin H

    2014-01-01

    BACKGROUND: Liver transplantation is an established treatment option for end-stage liver failure. To date, no consensus has been reached on the use of immunosuppressive T-cell specific antibody induction compared with corticosteroid induction of immunosuppression after liver transplantation....... OBJECTIVES: To assess the benefits and harms of T-cell specific antibody induction versus corticosteroid induction for prevention of acute rejection in liver transplant recipients. SEARCH METHODS: We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register...... to identify additional trials. SELECTION CRITERIA: We included all randomised clinical trials assessing immunosuppression with T-cell specific antibody induction versus corticosteroid induction in liver transplant recipients. Our inclusion criteria stated that participants within each included trial should...

  4. Characterization methods of nano-patterned surfaces generated by induction heating assisted injection molding

    DEFF Research Database (Denmark)

    Tang, Peter Torben; Ravn, Christian; Menotti, Stefano

    2015-01-01

    An induction heating-assisted injection molding (IHAIM) process developed by the authors is used to replicate surfaces containing random nano-patterns. The injection molding setup is developed so that an induction heating system rapidly heats the cavity wall at rates of up to 10◦C/s. In order...

  5. Pulsed inductive HF laser

    Energy Technology Data Exchange (ETDEWEB)

    Razhev, A M; Kargapol' tsev, E S [Institute of Laser Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk (Russian Federation); Churkin, D S; Demchuk, S V [Novosibirsk State University, Novosibirsk (Russian Federation)

    2016-03-31

    We report the results of experimentally investigated dependences of temporal, spectral and spatial characteristics of an inductive HF-laser generation on the pump conditions. Gas mixtures H{sub 2} – F{sub 2}(NF{sub 3} or SF6{sub 6}) and He(Ne) – H{sub 2} – F{sub 2}(NF{sub 3} or SF{sub 6}) were used as active media. The FWHM pulse duration reached 0.42 μs. This value corresponded to a pulsed power of 45 kW. For the first time, the emission spectrum of an inductive HF laser was investigated, which consisted of seven groups of bands with centres around the wavelengths of 2732, 2736, 2739, 2835, 2837, 2893 and 2913 nm. The cross section profile of the laser beam was a ring with a diameter of about 20 mm and width of about 5 mm. Parameters of laser operation in the repetitively pulsed regime were sufficiently stable. The amplitude instability of light pulses was no greater than 5% – 6%. (lasers)

  6. Differences in heavy-ion-induced DNA double-strand breaks in a mouse DNA repair-deficient mutant cell line (SL3-147) before and after chromatin proteolysis

    International Nuclear Information System (INIS)

    Murakami, Masahiro; Eguchi-Kasai, Kiyomi; Sato, Koki; Minohara, Shinichi; Kanai, Tatsuaki; Yatagai, Fumio.

    1995-01-01

    DNA double-strand breaks induced by X- or neon beam-irradiation in a DNA double-strand break-repair-deficient mutant cell line (SL3-147) were examined. The increase in the number of DNA double-strand breaks was dose-depend after irradiation with X-rays and neon beams and was enhanced by chromatin-proteolysis treatment before irradiation. These results suggest that the induction of DNA double-strand breaks by ionizing radiation, including heavy-ions, is influenced by the chromatin structure. (author)

  7. Radiomodifying effects of RAPTA C and CDDP on DNA strand break induction

    Czech Academy of Sciences Publication Activity Database

    Reimitz, D.; Davídková, Marie; Mestek, O.; Pinkas, Jiří; Kočišek, Jaroslav

    2017-01-01

    Roč. 141, DEC (2017), s. 229-234 ISSN 0969-806X R&D Projects: GA ČR GJ16-10995Y; GA MŠk LM2015056 Institutional support: RVO:61389005 ; RVO:61388955 Keywords : RAPTA C * Cisplatin * chemoradiation synergy * low energy electrons * DNA plasmid Subject RIV: BO - Biophysics; CF - Physical ; Theoretical Chemistry (UFCH-W) OBOR OECD: Biophysics; Physical chemistry (UFCH-W) Impact factor: 1.315, year: 2016

  8. Alkaline gel electrophoresis assay to detect DNA strand breaks and repair mechanisms in Escherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    Mattos, Jose Carlos Pelielo de; Motta, Ellen Serri da; Oliveira, Marcia Betania Nunes de; Dantas, Flavio Jose da Silva; Araujo, Adriano Caldeira de [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Dept. de Biofisica e Biometria. Lab. de Radio e Fotobiologia]. E-mail: jcmattos@uerj.br

    2008-12-15

    Reactive oxygen species (ROS) can induce lesions in different cellular targets, including DNA. Stannous chloride (SnCl{sub 2}) is a ROS generator, leading to lethality in Escherichia coli (E. coli), with the base excision repair (BER) mechanism playing a role in this process. Many techniques have been developed to detect genotoxicity, as comet assay, in eukaryotic cells, and plasmid DNA agarose gel electrophoresis. In this study, an adaptation of the alkaline gel electrophoresis method was carried out to ascertain the induction of strand breaks by SnCl{sub 2} in bacterial DNA, from E. coli BER mutants, and its repair pathway. Results obtained show that SnCl{sub 2} was able to induce DNA strand breaks in all strains tested. Moreover, endonuclease IV and exonuclease III play a role in DNA repair. On the whole, data has shown that the alkaline gel electrophoresis assay could be used both for studying DNA strand breaks induction and for associated repair mechanisms. (author)

  9. Vector control of induction machines

    CERN Document Server

    Robyns, Benoit

    2012-01-01

    After a brief introduction to the main law of physics and fundamental concepts inherent in electromechanical conversion, ""Vector Control of Induction Machines"" introduces the standard mathematical models for induction machines - whichever rotor technology is used - as well as several squirrel-cage induction machine vector-control strategies. The use of causal ordering graphs allows systematization of the design stage, as well as standardization of the structure of control devices. ""Vector Control of Induction Machines"" suggests a unique approach aimed at reducing parameter sensitivity for

  10. Borehole induction coil transmitter

    Science.gov (United States)

    Holladay, Gale; Wilt, Michael J.

    2002-01-01

    A borehole induction coil transmitter which is a part of a cross-borehole electromagnetic field system that is used for underground imaging applications. The transmitter consists of four major parts: 1) a wound ferrite or mu-metal core, 2) an array of tuning capacitors, 3) a current driver circuit board, and 4) a flux monitor. The core is wound with several hundred turns of wire and connected in series with the capacitor array, to produce a tuned coil. This tuned coil uses internal circuitry to generate sinusoidal signals that are transmitted through the earth to a receiver coil in another borehole. The transmitter can operate at frequencies from 1-200 kHz and supplies sufficient power to permit the field system to operate in boreholes separated by up to 400 meters.

  11. Induction heating using induction coils in series-parallel circuits

    Science.gov (United States)

    Matsen, Marc Rollo; Geren, William Preston; Miller, Robert James; Negley, Mark Alan; Dykstra, William Chet

    2017-11-14

    A part is inductively heated by multiple, self-regulating induction coil circuits having susceptors, coupled together in parallel and in series with an AC power supply. Each of the circuits includes a tuning capacitor that tunes the circuit to resonate at the frequency of AC power supply.

  12. Modelling oil price volatility with structural breaks

    International Nuclear Information System (INIS)

    Salisu, Afees A.; Fasanya, Ismail O.

    2013-01-01

    In this paper, we provide two main innovations: (i) we analyze oil prices of two prominent markets namely West Texas Intermediate (WTI) and Brent using the two recently developed tests by Narayan and Popp (2010) and Liu and Narayan, 2010 both of which allow for two structural breaks in the data series; and (ii) the latter method is modified to include both symmetric and asymmetric volatility models. We identify two structural breaks that occur in 1990 and 2008 which coincidentally correspond to the Iraqi/Kuwait conflict and the global financial crisis, respectively. We find evidence of persistence and leverage effects in the oil price volatility. While further extensions can be pursued, the consideration of asymmetric effects as well as structural breaks should not be jettisoned when modelling oil price volatility. - Highlights: ► We analyze oil price volatility using NP (2010) and LN (2010) tests. ► We modify the LN (2010) to account for leverage effects in oil price. ► We find two structural breaks that reflect major global crisis in the oil market. ► We find evidence of persistence and leverage effects in oil price volatility. ► Leverage effects and structural breaks are fundamental in oil price modelling.

  13. 9 CFR 590.522 - Breaking room operations.

    Science.gov (United States)

    2010-01-01

    ... personnel. (m) Ingredients and additives used in, or for, processing egg products, shall be handled in a..., Processing, and Facility Requirements § 590.522 Breaking room operations. (a) The breaking room shall be kept... clean and reasonably dry during breaking operations and free of egg meat and shells. (b) All breaking...

  14. Jet simulations and gamma-ray burst afterglow jet breaks

    NARCIS (Netherlands)

    van Eerten, H.J.; Meliani, Z.; Wijers, R.A.M.J.; Keppens, R.

    2011-01-01

    The conventional derivation of the gamma-ray burst afterglow jet break time uses only the blast wave fluid Lorentz factor and therefore leads to an achromatic break. We show that in general gamma-ray burst afterglow jet breaks are chromatic across the self-absorption break. Depending on

  15. Jet simulations and gamma-ray burst afterglow jet breaks

    NARCIS (Netherlands)

    van Eerten, H. J.; Meliani, Z.; Wijers, R.A.M.J.; Keppens, R.

    2010-01-01

    The conventional derivation of the gamma-ray burst afterglow jet break time uses only the blast wave fluid Lorentz factor and therefore leads to an achromatic break. We show that in general gamma-ray burst afterglow jet breaks are chromatic across the self-absorption break. Depending on

  16. Hydraulic Response of Caisson Breakwaters in Multidirectional Breaking and Non-Breaking Waves

    DEFF Research Database (Denmark)

    Grønbech, J.; Kofoed, Jens Peter; Hald, Tue

    1998-01-01

    The present paper concerns the results and findings of a physical study on wave impacts on vertical caisson breakwaters situated in irregular, multidirectional breaking seas. The study has taken place as part of the framework programme "Dynamic of Structures" financially supported by the Danish T...... breaking waves at deep water. The study on wave overtopping showed that the 3D wave overtopping formula suggested by Franco et al., 1995b, predicts the wave overtopping reasonable well for both non breaking and breaking waves at deep water.......The present paper concerns the results and findings of a physical study on wave impacts on vertical caisson breakwaters situated in irregular, multidirectional breaking seas. The study has taken place as part of the framework programme "Dynamic of Structures" financially supported by the Danish...... induced loading and overtopping on caisson breakwaters situated in breaking seas. Regarding the wave forces only minor differences between breaking and non breaking waves in deep water were observed, and it was found that the prediction formula of Goda also seems to apply well for multidirectionally...

  17. Break-glass handling exceptional situations in access control

    CERN Document Server

    Petritsch, Helmut

    2014-01-01

    Helmut Petritsch describes the first holistic approach to Break-Glass which covers the whole life-cycle: from access control modeling (pre-access), to logging the security-relevant system state during Break-Glass accesses (at-access), and the automated analysis of Break-Glass accesses (post-access). Break-Glass allows users to override security restrictions in exceptional situations. While several Break-Glass models specific to given access control models have already been discussed in research (e.g., extending RBAC with Break-Glass), the author introduces a generic Break-Glass model. The pres

  18. Increased rate of repair of ultraviolet-induced DNA strand breaks in mitogen stimulated lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Hamlet, S.M.; Lavin, M.F.; Jennings, P.A. (Queensland Univ., St. Lucia (Australia). Dept. of Biochemistry; Queensland Univ., St. Lucia (Australia). Dept. of Veterinary Pathology; Queensland Univ. St. Lucia (Australia). Dept. of Public Health)

    1982-05-01

    Previous results have shown that phytohaemagglutinin-stimulated bovine lymphocytes exhibit a peak of ultraviolet-induced DNA repair synthesis 3 to 4 days after addition of mitogen. The level of repair synthesis was approximately tenfold higher than that in unstimulated lymphocytes. These studies have been extended to examine the rate of repair of strand breaks in U.V.-irradiated bovine lymphocytes. The extent of breakage of DNA was shown to be the same in mitogen-stimulated and unstimulated lymphocytes from two breeds of cattle, when determined by sedimentation of nucleoids on sucrose gradients. However, in mitogen-stimulated cells the time taken to repair DNA strand breaks was 6 hours compared with 12 hours in stationary phase lymphocytes after a U.V. dose of 5 J/m/sup 2/. These results suggest that the increased rate of repair of strand breaks is due to the induction of enzymes involved at the post-incision stage of DNA repair. Thus the increased level of repair synthesis observed in earlier work correlates with an increased rate of repair of DNA strand breaks in phytohaemagglutinin-stimulated bovine lymphocytes.

  19. Increased rate of repair of ultraviolet-induced DNA strand breaks in mitogen stimulated lymphocytes

    International Nuclear Information System (INIS)

    Hamlet, S.M.; Lavin, M.F.; Jennings, P.A.; Queensland Univ., St. Lucia; Queensland Univ. St. Lucia

    1982-01-01

    Previous results have shown that phytohaemagglutinin-stimulated bovine lymphocytes exhibit a peak of ultraviolet-induced DNA repair synthesis 3 to 4 days after addition of mitogen. The level of repair synthesis was approximately tenfold higher than that in unstimulated lymphocytes. These studies have been extended to examine the rate of repair of strand breaks in U.V.-irradiated bovine lymphocytes. The extent of breakage of DNA was shown to be the same in mitogen-stimulated and unstimulated lymphocytes from two breeds of cattle, when determined by sedimentation of nucleoids on sucrose gradients. However, in mitogen-stimulated cells the time taken to repair DNA strand breaks was 6 hours compared with 12 hours in stationary phase lymphocytes after a U.V. dose of 5 J/m 2 . These results suggest that the increased rate of repair of strand breaks is due to the induction of enzymes involved at the post-incision stage of DNA repair. Thus the increased level of repair synthesis observed in earlier work correlates with an increased rate of repair of DNA strand breaks in phytohaemagglutinin-stimulated bovine lymphocytes. (author)

  20. Jump dynamics with structural breaks for crude oil prices

    International Nuclear Information System (INIS)

    Lee, Yen-Hsien; Hu, Hsu-Ning; Chiou, Jer-Shiou

    2010-01-01

    This study investigates the joint phenomena of permanent and transitory components in conditional variance and jump intensity along with verification of structural breaks for crude oil prices. We adopt a Component-ARJI model with structural break analysis, utilizing daily data on West Texas Intermediate crude oil spot and futures contracts. The analytical results verify the existence of permanent and transitory components in conditional variance, with the permanent component of conditional variance increasing with the occurrence of a sudden major event (such as the Iraqi Invasion of Kuwait, Operation Desert Storm and the war between the US and Iraq), and a relatively greater increase in the transitory component over the same period. Notably, jump intensity fluctuates with an increase in the transitory component of conditional variance in response to abnormal events. It is the transitory component which serves as the primary influential factor for jumps in returns; therefore, speculators are willing to take large risks, particularly with respect to anticipating future price movements, or gambling, in the hopes of rapidly making substantial gains; thus, speculators prefer the temporary volatility component and engage in trade activities. However, investors prefer the permanent volatility component, because they may well be better off relocating their assets into more stable portfolios to outperform the market portfolio over the long run. (author)

  1. Jump dynamics with structural breaks for crude oil prices

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yen-Hsien [Department of Finance, Chung Yuan Christian University (China); Hu, Hsu-Ning [Department of Money, Banking and Finance, TamKang University (China); Chiou, Jer-Shiou [Department of Finance and Banking, Shih Chien University, 70 Ta-Chih Street, Taipei 104 (China)

    2010-03-15

    This study investigates the joint phenomena of permanent and transitory components in conditional variance and jump intensity along with verification of structural breaks for crude oil prices. We adopt a Component-ARJI model with structural break analysis, utilizing daily data on West Texas Intermediate crude oil spot and futures contracts. The analytical results verify the existence of permanent and transitory components in conditional variance, with the permanent component of conditional variance increasing with the occurrence of a sudden major event (such as the Iraqi Invasion of Kuwait, Operation Desert Storm and the war between the US and Iraq), and a relatively greater increase in the transitory component over the same period. Notably, jump intensity fluctuates with an increase in the transitory component of conditional variance in response to abnormal events. It is the transitory component which serves as the primary influential factor for jumps in returns; therefore, speculators are willing to take large risks, particularly with respect to anticipating future price movements, or gambling, in the hopes of rapidly making substantial gains; thus, speculators prefer the temporary volatility component and engage in trade activities. However, investors prefer the permanent volatility component, because they may well be better off relocating their assets into more stable portfolios to outperform the market portfolio over the long run. (author)

  2. Yield of single-strand breaks in the DNA of E. coli 10 msec after irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Fox, R A; Fielden, E M; Sapora, O [Institute of Cancer Research, Sutton (UK). Surrey Branch

    1976-04-01

    The rapid mixing of 0.3M alkali with a suspension of E.coli B/r 6 +- 3 and 144 +- 3 msec after irradiation with electrons (4.3 MeV, 0 to 50 krad) has been used to make a comparison of the yields of single strand breaks in the presence and absence of oxygen. No significant difference was observed between the numbers of single strand breaks appearing at 6 and 144 msec after irradiation. Assuming that mixing with alkali inactivates the cellular repair enzymes within several milliseconds, these results indicate that enzymic repair does not operate within this time scale. It seems probable that radiation chemical processes are responsible for the initial oxygen effect on single strand breaks.

  3. U(1) mediation of flux supersymmetry breaking

    Science.gov (United States)

    Grimm, Thomas W.; Klemm, Albrecht

    2008-10-01

    We study the mediation of supersymmetry breaking triggered by background fluxes in Type II string compactifications with Script N = 1 supersymmetry. The mediation arises due to an U(1) vector multiplet coupling to both a hidden supersymmetry breaking flux sector and a visible D-brane sector. The required internal manifolds can be constructed by non-Kähler resolutions of singular Calabi-Yau manifolds. The effective action encoding the U(1) coupling is then determined in terms of the global topological properties of the internal space. We investigate suitable local geometries for the hidden and visible sector in detail. This includes a systematic study of orientifold symmetries of del Pezzo surfaces realized in compact geometries after geometric transition. We construct compact examples admitting the key properties to realize flux supersymmetry breaking and U(1) mediation. Their toric realization allows us to analyze the geometry of curve classes and confirm the topological connection between the hidden and visible sector.

  4. Report of Break Out Group 1

    DEFF Research Database (Denmark)

    Alward, Randy; Carley, Kathleen M.; Madsen, Fredrik Huitfeldt

    2006-01-01

    , action" (OODA) loop. The break out group discussed vulnerability presentation needs common across various application domains, particularly in support of network discovery and network analysis tasks in those domains. Finally, the break out group wished to determine whether there is a means...... of characterizing a vulnerability. This would take into account the potential for the vulnerability to be exploited as well as the potential impact on the operations supported by the network, and on the network structure itself, of a successful exploit of that vulnerability.......To help understand a network and its ability to continue operating when under attack, the break out group discussed issues that need to be considered when presenting network vulnerability information to an analyst, manager or commander in effective support of that person's "observe, orient, decide...

  5. U(1) mediation of flux supersymmetry breaking

    International Nuclear Information System (INIS)

    Grimm, Thomas W.; Klemm, Albrecht

    2008-01-01

    We study the mediation of supersymmetry breaking triggered by background fluxes in Type II string compactifications with N = 1 supersymmetry. The mediation arises due to an U(1) vector multiplet coupling to both a hidden supersymmetry breaking flux sector and a visible D-brane sector. The required internal manifolds can be constructed by non-Kaehler resolutions of singular Calabi-Yau manifolds. The effective action encoding the U(1) coupling is then determined in terms of the global topological properties of the internal space. We investigate suitable local geometries for the hidden and visible sector in detail. This includes a systematic study of orientifold symmetries of del Pezzo surfaces realized in compact geometries after geometric transition. We construct compact examples admitting the key properties to realize flux supersymmetry breaking and U(1) mediation. Their toric realization allows us to analyze the geometry of curve classes and confirm the topological connection between the hidden and visible sector.

  6. Large eddy simulation of breaking waves

    DEFF Research Database (Denmark)

    Christensen, Erik Damgaard; Deigaard, Rolf

    2001-01-01

    A numerical model is used to simulate wave breaking, the large scale water motions and turbulence induced by the breaking process. The model consists of a free surface model using the surface markers method combined with a three-dimensional model that solves the flow equations. The turbulence....... The incoming waves are specified by a flux boundary condition. The waves are approaching in the shore-normal direction and are breaking on a plane, constant slope beach. The first few wave periods are simulated by a two-dimensional model in the vertical plane normal to the beach line. The model describes...... the steepening and the overturning of the wave. At a given instant, the model domain is extended to three dimensions, and the two-dimensional flow field develops spontaneously three-dimensional flow features with turbulent eddies. After a few wave periods, stationary (periodic) conditions are achieved...

  7. Workshop on electroweak symmetry breaking: proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Hinchliffe, I. (ed.)

    1984-10-01

    A theoretical workshop on electroweak symmetry breaking at the Superconducting Supercollider was held at Lawrence Berkeley Laboratory, June 4-22, 1984. The purpose of the workshop was to focus theoretical attention on the ways in which experimentation at the SSC could reveal manifestations of the phenomenon responsible for electroweak symmetry breaking. This issue represents, at present, the most compelling scientific argument for the need to explore the energy region to be made accessible by the SSC, and a major aim of the workshop was to involve a broad cross section of particle theorists in the ongoing process of sharpening the requirements for both accelerator and detector design that will ensure detection and identification of meaningful signals, whatever form the electroweak symmetry breaking phenomenon should actually take. Separate entries were prepared for the data base for the papers presented.

  8. Workshop on electroweak symmetry breaking: proceedings

    International Nuclear Information System (INIS)

    Hinchliffe, I.

    1984-10-01

    A theoretical workshop on electroweak symmetry breaking at the Superconducting Supercollider was held at Lawrence Berkeley Laboratory, June 4-22, 1984. The purpose of the workshop was to focus theoretical attention on the ways in which experimentation at the SSC could reveal manifestations of the phenomenon responsible for electroweak symmetry breaking. This issue represents, at present, the most compelling scientific argument for the need to explore the energy region to be made accessible by the SSC, and a major aim of the workshop was to involve a broad cross section of particle theorists in the ongoing process of sharpening the requirements for both accelerator and detector design that will ensure detection and identification of meaningful signals, whatever form the electroweak symmetry breaking phenomenon should actually take. Separate entries were prepared for the data base for the papers presented

  9. Breaking bad news in cancer patients.

    Science.gov (United States)

    Konstantis, Apostolos; Exiara, Triada

    2015-01-01

    In a regional hospital, many patients are newly diagnosed with cancer. Breaking the bad news in these patients and their relatives is a tough task. Many doctors are not experienced in talking to patients about death or death-related diseases. In recent years, there have been great efforts to change the current situation. The aim of this study was to investigate the experience and education of medical personnel in breaking bad news in a secondary hospital. 59 doctors from General Hospital of Komotini, Greece were included in the study. All the doctors were in clinical specialties that treated cancer patients. A brief questionnaire was developed based on current guidelines such as Baile/SPIKES framework and the ABCDE mnemonic. Residents are involved in delivering bad news less frequently than specialists. Only 21 doctors (35.59%) had specific training on breaking bad news. 20 doctors (33.90%) were aware of the available techniques and protocols on breaking bad news. 47 doctors (79.66%) had a consistent plan for breaking bad news. 57 (96.61%) delivered bad news in a quiet place, 53 (89.83%) ensured no interruptions and enough time, 53 (89.83%) used simple words and 54 (91.53%) checked for understanding and did not rush through the news. 46 doctors (77.97%) allowed relatives to determine patient's knowledge about the disease. There were low rates of specific training in breaking bad news. However, the selected location, the physician's speech and their plan were according to current guidelines.

  10. Breaking bad news in cancer patients

    Directory of Open Access Journals (Sweden)

    Apostolos Konstantis

    2015-01-01

    Full Text Available Objective: In a regional hospital, many patients are newly diagnosed with cancer. Breaking the bad news in these patients and their relatives is a tough task. Many doctors are not experienced in talking to patients about death or death-related diseases. In recent years, there have been great efforts to change the current situation. The aim of this study was to investigate the experience and education of medical personnel in breaking bad news in a secondary hospital. Materials and Methods: 59 doctors from General Hospital of Komotini, Greece were included in the study. All the doctors were in clinical specialties that treated cancer patients. A brief questionnaire was developed based on current guidelines such as Baile/SPIKES framework and the ABCDE mnemonic. Results: Residents are involved in delivering bad news less frequently than specialists. Only 21 doctors (35.59% had specific training on breaking bad news. 20 doctors (33.90% were aware of the available techniques and protocols on breaking bad news. 47 doctors (79.66% had a consistent plan for breaking bad news. 57 (96.61% delivered bad news in a quiet place, 53 (89.83% ensured no interruptions and enough time, 53 (89.83% used simple words and 54 (91.53% checked for understanding and did not rush through the news. 46 doctors (77.97% allowed relatives to determine patient′s knowledge about the disease. Conclusions: There were low rates of specific training in breaking bad news. However, the selected location, the physician′s speech and their plan were according to current guidelines.

  11. Probabilistic inductive inference: a survey

    OpenAIRE

    Ambainis, Andris

    2001-01-01

    Inductive inference is a recursion-theoretic theory of learning, first developed by E. M. Gold (1967). This paper surveys developments in probabilistic inductive inference. We mainly focus on finite inference of recursive functions, since this simple paradigm has produced the most interesting (and most complex) results.

  12. A Student Teamwork Induction Protocol

    Science.gov (United States)

    Kamau, Caroline; Spong, Abigail

    2015-01-01

    Faulty group processes have harmful effects on performance but there is little research about intervention protocols to pre-empt them in higher education. This naturalistic experiment compared a control cohort with an inducted cohort. The inducted cohort attended a workshop, consultations, elected a leader and used tools (a group log and group…

  13. Sampling Assumptions in Inductive Generalization

    Science.gov (United States)

    Navarro, Daniel J.; Dry, Matthew J.; Lee, Michael D.

    2012-01-01

    Inductive generalization, where people go beyond the data provided, is a basic cognitive capability, and it underpins theoretical accounts of learning, categorization, and decision making. To complete the inductive leap needed for generalization, people must make a key "sampling" assumption about how the available data were generated.…

  14. From Inductive Reasoning to Proof

    Science.gov (United States)

    Yopp, David A.

    2009-01-01

    Mathematical proof is an expression of deductive reasoning (drawing conclusions from previous assertions). However, it is often inductive reasoning (conclusions drawn on the basis of examples) that helps learners form their deductive arguments, or proof. In addition, not all inductive arguments generate more formal arguments. This article draws a…

  15. Covariation in Natural Causal Induction.

    Science.gov (United States)

    Cheng, Patricia W.; Novick, Laura R.

    1991-01-01

    Biases and models usually offered by cognitive and social psychology and by philosophy to explain causal induction are evaluated with respect to focal sets (contextually determined sets of events over which covariation is computed). A probabilistic contrast model is proposed as underlying covariation computation in natural causal induction. (SLD)

  16. Economic implications of labor induction.

    Science.gov (United States)

    Garcia-Simon, Raquel; Montañes, Antonio; Clemente, Jesús; Del Pino, María D; Romero, Manuel A; Fabre, Ernesto; Oros, Daniel

    2016-04-01

    To assess health service costs associated with labor induction according to different clinical situations in a tertiary-level hospital. In a prospective study, individual patient cost data were assessed for women admitted for induction of labor at a tertiary hospital in Spain between November 1, 2012, and August 31, 2013. The costs of labor induction were estimated according to maternal and neonatal outcomes, method of delivery, cervical condition at admission, and obstetric indication. Direct costs including professional fees, epidural, maternal stay, consumables, and drugs were calculated. Overall, 412 women were included in the final cost analysis. The mean total cost of labor induction was €3589.87 (95% confidence interval [CI] 3475.13-3704.61). Cesarean delivery after labor induction (€4830.45, 95% CI 4623.13-5037.58) was significantly more expensive than spontaneous delivery (€3037.45, 95% CI 2966.91-3179.99) and instrumental vaginal delivery (€3344.31, 95%CI 3151.69-3536.93). The total cost for patients with a very unfavorable cervix (Bishop score Labor induction for hypertensive disorders of pregnancy was the most expensive obstetric indication for induction of labor (€4347.32, 95% CI 3890.45-4804.18). Following the induction of labor, a number of patient- and treatment-related factors influence costs associated with delivery. Copyright © 2015 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

  17. Implications of career break from personal and company perspectives

    OpenAIRE

    Vuorinen, Niina

    2017-01-01

    The objective of this study is to show the implications that career breaks have on individuals and employers. The intensions are to identify personal motivations for career breaks, and if the breaks change the careers of the people taking them. Furthermore, this study intends to understand how career breaks are viewed by employers, and if career breaks are becoming more acceptable internationally. The theoretical framework was based on description of work and careers both from employee an...

  18. Coupled simulation of steam line break accident

    International Nuclear Information System (INIS)

    Royer, E.; Raimond, E.; Caruge, D.

    2000-01-01

    The steam line break is a PWR type reactor design accident, which concerns coupled physical phenomena. To control these problems simulation are needed to define and validate the operating procedures. The benchmark OECD PWR MSLB (Main Steam Line Break) has been proposed by the OECD to validate the feasibility and the contribution of the multi-dimensional tools in the simulation of the core transients. First the benchmark OECD PWR MSLB is presented. Then the analysis of the three exercises (system with pinpoint kinetic, three-dimensional core and whole system with three-dimensional core) are discussed. (A.L.B.)

  19. The experimental investigation of supersymmetry breaking

    International Nuclear Information System (INIS)

    Peskin, M.E.

    1996-04-01

    If Nature is supersymmetric at the weak interaction scale, what can we hope to learn from experiments on supersymmetric particles? The most mysterious aspect of phenomenological supersymmetry is the mechanism of spontaneous supersymmetry breaking. This mechanism ties the observable pattern of supersymmetric particle masses to aspects of the underlying unified theory at very small distance scales. In this article, I will discuss a systematic experimental program to determine the mechanism of supersymmetry breaking. Both pp and e + e - colliders of the next generation play an essential role

  20. What records have we been breaking?

    Science.gov (United States)

    Bartholow, J.M.; Milhous, R.

    2002-01-01

    "Today was another record-breaking day," the evening radio or television declares. High temperatures, low temperatures, floods, drought - take your choice. But how can we put these pronouncements in perspective? What do they really mean?We present two types of information in this article: 1) an analysis of daily air temperature and precipitation for Fort Collins and 2) an analysis of annual precipitation for Fort Collins. Each analysis provides a different meaning to the statement about a record-breaking day or year.

  1. Detecting Structural Breaks using Hidden Markov Models

    DEFF Research Database (Denmark)

    Ntantamis, Christos

    Testing for structural breaks and identifying their location is essential for econometric modeling. In this paper, a Hidden Markov Model (HMM) approach is used in order to perform these tasks. Breaks are defined as the data points where the underlying Markov Chain switches from one state to another....... The estimation of the HMM is conducted using a variant of the Iterative Conditional Expectation-Generalized Mixture (ICE-GEMI) algorithm proposed by Delignon et al. (1997), that permits analysis of the conditional distributions of economic data and allows for different functional forms across regimes...

  2. Axions from cooling compact stars: pair-breaking processes

    Energy Technology Data Exchange (ETDEWEB)

    Keller, Jochen; Sedrakian, Armen [Frankfurt Univ. (Germany). Inst. fuer Theoretische Physik

    2013-07-01

    Once formed in a supernova explosion, a neutron star cools rapidly via neutrino emission during the first 10{sup 4}-10{sup 5} years of its life-time. Here we compute the axion emission rate from baryonic components of a star at temperatures below their respective critical temperatures T{sub c} for normal-superfluid phase transition. The axion production is driven by a charge neutral weak process, associated with Cooper pair breaking and recombination. The requirement that the axion cooling does not overshadow the neutrino cooling yields a lower bound on the axion decay constant f{sub a} > 6 x 10{sup 9} T{sup -1}{sub c9} GeV, with T{sub c9} = T{sub c}/10{sup 9} K. This translates into an upper bound on the axion mass m{sub a} < 10{sup -3} T{sub c9} eV.

  3. Axions from cooling compact stars: Pair-breaking processes

    Energy Technology Data Exchange (ETDEWEB)

    Keller, Jochen [Institute for Theoretical Physics, J.W. Goethe-University, D-60438 Frankfurt am Main (Germany); Sedrakian, Armen, E-mail: sedrakian@th.physik.uni-frankfurt.de [Institute for Theoretical Physics, J.W. Goethe-University, D-60438 Frankfurt am Main (Germany)

    2013-01-02

    Once formed in a supernova explosion, a neutron star cools rapidly via neutrino emission during the first 10{sup 4}-10{sup 5} yr of its life-time. Here we compute the axion emission rate from baryonic components of a star at temperatures below their respective critical temperatures T{sub c} for normal-superfluid phase transition. The axion production is driven by a charge neutral weak process, associated with Cooper pair breaking and recombination. The requirement that the axion cooling does not overshadow the neutrino cooling puts a lower bound on the axion decay constant f{sub a}>6 Multiplication-Sign 10{sup 9}T{sub c9}{sup -1} GeV, with T{sub c9}=T{sub c}/10{sup 9} K. This translates into an upper bound on the axion mass m{sub a}<10{sup -3}T{sub c9} eV.

  4. Peaking cladding temperature and break equivalent size of intermediate break loss of coolant accident

    International Nuclear Information System (INIS)

    Luo Bangqi

    2012-01-01

    The analysis results of intermediate break loss of coolant accident for the nuclear power plant of million kw level showed to be as following: (1) At the begin of life, the break occur simultaneity reactor shutdown with L(X)P. it's equivalent break size and peaking cladding temperature is respectively 20 cm and 849℃. (2) At the begin of life, the break occur simultaneity reactor shutdown without loop. the reactor coolant pumps will be stop after reactor shutdown 10 minutes, it's equivalent break size and peaking cladding temperature is respectively 10.5 cm and 921℃. (3) At the bur up of 31 GWd/t(EOC1). the break occur simultaneity reactor shutdown without loop, the reactor coolant pumps will be stop after reactor shutdown 20 minutes, it's equivalent break size and peaking cladding temperature is respectively 8 cm and 1145℃. The above analysis results showed that the peaking cladding temperature of intermediate break loss of coolant accident is not only related with the break equivalent size and core bur up, and is closely related with the stop time of coolant pumps because the coolant pumps would drive the coolant from safety system to produce the seal loop in break loop and affect the core coolant flow, results in the fuel cladding temperature increasing or damaging. Therefore, the break spectrum, burn up spectrum, the stop time of coolant pumps and operator action time will need to detail analysis and provide appropriate operating procedure, otherwise the peaking cladding temperature will exceed 1204℃ and threaten the safety of the reactor core when the intermediate break loss of coolant accident occur in some break equivalent size, burn up, stop pumps time and operator action not appropriate. The pressurizer pressure low signal simultaneity containment pressure higher signal were used as the operator manual close the signal of reactor coolant pumps after reactor shutdown of 20 minutes. have successful solved the operator intervention time from 10 minutes

  5. Contribution of sleep to the repair of neuronal DNA double-strand breaks: evidence from flies and mice

    OpenAIRE

    Bellesi, Michele; Bushey, Daniel; Chini, Mattia; Tononi, Giulio; Cirelli, Chiara

    2016-01-01

    Exploration of a novel environment leads to neuronal DNA double-strand breaks (DSBs). These DSBs are generated by type 2 topoisomerase to relieve topological constrains that limit transcription of plasticity-related immediate early genes. If not promptly repaired, however, DSBs may lead to cell death. Since the induction of plasticity-related genes is higher in wake than in sleep, we asked whether it is specifically wake associated with synaptic plasticity that leads to DSBs, and whether slee...

  6. Radiation-induced DNA double strand breaks in Ehrlich ascites tumour cells and their possible effects on cell survival

    International Nuclear Information System (INIS)

    Bloecher, D.

    1981-01-01

    A method to prepare high-molecular, pure DNA with the aid of enzymes, detergents, and heat treatment is presented. A sedimentation technique with neutral density gradients has been introduced which permits mass separation and molecular mass analysis of high-molecular DNA (msub(r) 10 ). Using this method, the induction of DNA double strand breaks (DSB) in the dose range between 10 Gy [de

  7. Interferon induction by adenoviruses

    Energy Technology Data Exchange (ETDEWEB)

    Beladi, I; Bakay, M; Pusztai, R; Mucsi, I; Tarodi, B [University Medical School, Szeged (Hungary). Inst. of Microbiology

    1979-02-01

    All human, simian, bovine and avian adenovirus types tested so far and the canine hepatitis virus induce interferon production in chick cells. This finding indicated this property to be characteristic for viruses belonging to the adenovirus group. Trypsin treatment, which had no effect upon the infectivity, diminished or eliminated the interferon-inducing abilities of crude adenoviruses, and thus the need for a trypsin-sensitive protein in interferon induction was suggested. T antigen and interferon were formed simultaneously in chick embryo fibroblast cells infected with human adenovirus type 12, and there-fore the adenovirus-specific T antigen was resitant to the action of endogenous interferon synthetized by the same cells. In chicks inoculated with human types, the appearance of interferon was biphasic: an 'early' and a 'late' interferon could be demonstrated with maximum titre 4 and 10 hr, respectively, after virus infection. In chicks infected with adenoviruses, first interferon production and then a decreased primary immune response to sheep red blood cells was observed. It was assumed that in adenovirus-infected chicks the interferon produced by viral stimulus resulted in a transient immunosuppression.

  8. Computational and experimental study of the effect of mass transfer on liquid jet break-up

    Science.gov (United States)

    Schetz, J. A.; Situ, M.

    1983-06-01

    A computational method has been developed to predict the effect of mass transfer on liquid jet break-up in coaxial, low velocity gas streams. Two conditions, both with and without the effect of mass transfer on the jet break-up, are calculated, and compared with experimental results and the classical linear theory. Methanol and water were used as the injectants. The numerical solution can predict the instantaneous shape of the jet surface and the break-up time, and it is very close to the experimental results. The numerical solutions and the experimental results both indicate that the wave number of the maximum instability is about 6.9, higher than 4.51 which was predicted by Rayleigh's linear theory. The experimental results and numerical solution show that the growth of the amplitude of the trough is faster than the growth of the amplitude of the crest, especially for a rapidly vaporizing jet. The numerical solutions show that for the small rates of evaporation, the effect of the mass transfer on the interface has a stabilizing effect near the wave number for maximum instability. Inversely, it has a destabilizing effect far from the wave number for maximum instability. For rapid evaporation, the effect of the mass transfer always has a destabilizing effect and decreases the break-up time of the jet.

  9. Contrasting Patterns of Diterpene Acid Induction by Red Pine and White Spruce to Simulated Bark Beetle Attack, and Interspecific Differences in Sensitivity Among Fungal Associates

    Science.gov (United States)

    Charles J. Mason; Kier D. Klepzig; Brian J. Kopper; Philip J. Kersten; Barbara L. Illman; Kenneth F. Raffa

    2015-01-01

    Conifers possess a suite of physiochemical defenses that protect their subcortical tissues from bark beetle -fungal complexes. These defenses include rapid induction of terpenoids and phenolics at the site of attack. Studies of the distribution, induction, and bioactivity of conifer terpenoids have focused heavily on monoterpenes. We assessed induction of diterpene...

  10. Rapid shallow breathing

    Science.gov (United States)

    Tachypnea; Breathing - rapid and shallow; Fast shallow breathing; Respiratory rate - rapid and shallow ... Shallow, rapid breathing has many possible medical causes, including: Asthma Blood clot in an artery in the ...

  11. Dynamical Symmetry Breaking in RN Quantum Gravity

    Directory of Open Access Journals (Sweden)

    A. T. Kotvytskiy

    2011-01-01

    Full Text Available We show that in the RN gravitation model, there is no dynamical symmetry breaking effect in the formalism of the Schwinger-Dyson equation (in flat background space-time. A general formula for the second variation of the gravitational action is obtained from the quantum corrections hμν (in arbitrary background metrics.

  12. Numerical Simulation of a Seaway with Breaking

    Science.gov (United States)

    Dommermuth, Douglas; O'Shea, Thomas; Brucker, Kyle; Wyatt, Donald

    2012-11-01

    The focus of this presentation is to describe the recent efforts to simulate a fully non-linear seaway with breaking by using a high-order spectral (HOS) solution of the free-surface boundary value problem to drive a three-dimensional Volume of Fluid (VOF) solution. Historically, the two main types of simulations to simulate free-surface flows are the boundary integral equations method (BIEM) and high-order spectral (HOS) methods. BIEM calculations fail at the point at which the surface impacts upon itself, if not sooner, and HOS methods can only simulate a single valued free-surface. Both also employ a single-phase approximation in which the effects of the air on the water are neglected. Due to these limitations they are unable to simulate breaking waves and air entrainment. The Volume of Fluid (VOF) method on the other hand is suitable for modeling breaking waves and air entrainment. However it is computationally intractable to generate a realistic non-linear sea-state. Here, we use the HOS solution to quickly drive, or nudge, the VOF solution into a non-linear state. The computational strategies, mathematical formulation, and numerical implementation will be discussed. The results of the VOF simulation of a seaway with breaking will also be presented, and compared to the single phase, single valued HOS results.

  13. Controlling break-the-glass through alignment

    NARCIS (Netherlands)

    Adriansyah, A.; Dongen, van B.F.; Zannone, N.

    2013-01-01

    Modern IT systems have to deal with unpredictable situations and exceptions more and more often. In contrast, security mechanisms are usually very rigid. This causes organizations to employ functionality like break-the-glass that allows users to bypass security mechanisms in case of emergencies.

  14. The issue of supersymmetry breaking in strings

    International Nuclear Information System (INIS)

    Binetruy, P.

    1989-12-01

    We discuss the central role that supersymmetry plays in string models, both in spacetime and at the level of the string world-sheet. The problems associated with supersymmetry-breaking are reviewed together with some of the attempts to solve them, in the string as well as the field theory approach

  15. Lifshitz-sector mediated SUSY breaking

    International Nuclear Information System (INIS)

    Pospelov, Maxim; Tamarit, Carlos

    2014-01-01

    We propose a novel mechanism of SUSY breaking by coupling a Lorentz-invariant supersymmetric matter sector to non-supersymmetric gravitational interactions with Lifshitz scaling. The improved UV properties of Lifshitz propagators moderate the otherwise uncontrollable ultraviolet divergences induced by gravitational loops. This ensures that both the amount of induced Lorentz violation and SUSY breaking in the matter sector are controlled by Λ HL 2 /M P 2 , the ratio of the Hořava-Lifshitz cross-over scale Λ HL to the Planck scale M P . This ratio can be kept very small, providing a novel way of explicitly breaking supersymmetry without reintroducing fine-tuning. We illustrate our idea by considering a model of scalar gravity with Hořava-Lifshitz scaling coupled to a supersymmetric Wess-Zumino matter sector, in which we compute the two-loop SUSY breaking corrections to the masses of the light scalars due to the gravitational interactions and the heavy fields

  16. Atmospheric noise of a breaking tidal bore.

    Science.gov (United States)

    Chanson, Hubert

    2016-01-01

    A tidal bore is a surge of waters propagating upstream in an estuary as the tidal flow turns to rising and the flood tide propagates into a funnel-shaped system. Large tidal bores have a marked breaking roller. The sounds generated by breaking tidal bores were herein investigated in the field (Qiantang River) and in laboratory. The sound pressure record showed two dominant periods, with some similarity with an earlier study [Chanson (2009). J. Acoust. Soc. Am. 125(6), 3561-3568]. The two distinct phases were the incoming tidal bore when the sound amplitude increased with the approaching bore, and the passage of the tidal bore in front of the microphone when loud and powerful noises were heard. The dominant frequency ranged from 57 to 131 Hz in the Qiantang River bore. A comparison between laboratory and prototype tidal bores illustrated both common features and differences. The low pitch sound of the breaking bore had a dominant frequency close to the collective oscillations of bubble clouds, which could be modeled with a bubble cloud model using a transverse dimension of the bore roller. The findings suggest that this model might be over simplistic in the case of a powerful breaking bore, like that of the Qiantang River.

  17. Critical wind speed at which trees break

    Science.gov (United States)

    Virot, E.; Ponomarenko, A.; Dehandschoewercker, É.; Quéré, D.; Clanet, C.

    2016-02-01

    Data from storms suggest that the critical wind speed at which trees break is constant (≃42 m /s ), regardless of tree characteristics. We question the physical origin of this observation both experimentally and theoretically. By combining Hooke's law, Griffith's criterion, and tree allometry, we show that the critical wind speed indeed hardly depends on the height, diameter, and elastic properties of trees.

  18. Spontaneous symmetry breaking in N = 2 supergravity

    International Nuclear Information System (INIS)

    Zinov'ev, Y.M.

    1987-01-01

    A model describing the interaction of N = 2 supergravity with a vector and a linear multiplet is constructed. The model admits the introduction of spontaneous supersymmetry breaking with two arbitrary scales, one of which can be equal to zero, corresponding to the partial super-Higgs effect (N = 2→N = 1). The cosmological term is automatically equal to zero

  19. Firm break-up and performance

    Czech Academy of Sciences Publication Activity Database

    Kočenda, Evžen; Hanousek, Jan

    2012-01-01

    Roč. 13, č. 2 (2012), s. 121-143 ISSN 1435-6104 R&D Projects: GA ČR GA402/09/1595 Institutional support: PRVOUK-P23 Keywords : break-up of firms * corporate performance * ownership changes Subject RIV: AH - Economics Impact factor: 0.588, year: 2012

  20. Pair breaking and charge relaxation in superconductors

    International Nuclear Information System (INIS)

    Nielson, J.B.; Pethick, C.J.; Rammer, J.; Smith, H.

    1982-01-01

    We present a general formalism based on the quasiclassical Green's function for calculating charge imbalance in nonequilibrium superconductors. Our discussion is sufficiently general that it applies at arbitrary temperatures, and under conditions when the width of quasiparticle states are appreciable due to pair breaking processes, and when strong coupling effects are significant. As a first application we demonstrate in detail how in the limit of smallpair breaking and for a weak coupling superconductor the collision term in the formalism reduces to the one in the quasiparticle Boltzmann equation. We next treat the case of charge imbalance generated by tunnel injection, with pair breaking by phonons and magnetic impurities. Over the range of temperatures investigated exerimentally to date, the calculated charge imbalance is rather close to that evaluated using the Boltzmann equation, even if pair braeking is so strong as almost to destroy superconductivity. Finally we consider charge imbalance generated by the combined influence of a supercurrent and a temperature gradient. We give calculations for a dirty superconductor with scattering by phonons as the pair breaking mechanism, and the results give a reasonable account of the experimental data of Clarke, Fjordboge, and Lindelof. We carry out calculations for the case of impurity scattering along which are valid not only in the clean and dirty limits, but also for intermediate situations. These enable us to see how the large contribution to the charge imbalance found for energies close to the gap edge in the clean case is reduced with increasing impurity scattering

  1. Path-breaking books in regional science

    NARCIS (Netherlands)

    Waldorf, BS

    This article presents a collection of regional science books that long-standing members of the Regional Science Association International (RSAI) identified as path-breaking books. The most frequently nominated books include the "classics" by Isard, the seminal books in urban economics by Alonso,

  2. Fragmentation in DNA double-strand breaks

    International Nuclear Information System (INIS)

    Wei Zhiyong; Suzhou Univ., Suzhou; Zhang Lihui; Li Ming; Fan Wo; Xu Yujie

    2005-01-01

    DNA double strand breaks are important lesions induced by irradiations. Random breakage model or quantification supported by this concept is suitable to analyze DNA double strand break data induced by low LET radiation, but deviation from random breakage model is more evident in high LET radiation data analysis. In this work we develop a new method, statistical fragmentation model, to analyze the fragmentation process of DNA double strand breaks. After charged particles enter the biological cell, they produce ionizations along their tracks, and transfer their energies to the cells and break the cellular DNA strands into fragments. The probable distribution of the fragments is obtained under the condition in which the entropy is maximum. Under the approximation E≅E 0 + E 1 l + E 2 l 2 , the distribution functions are obtained as exp(αl + βl 2 ). There are two components, the one proportional to exp(βl 2 ), mainly contributes to the low mass fragment yields, the other component, proportional to exp(αl), decreases slowly as the mass of the fragments increases. Numerical solution of the constraint equations provides parameters α and β. Experimental data, especially when the energy deposition is higher, support the statistical fragmentation model. (authors)

  3. Critical wind speed at which trees break.

    Science.gov (United States)

    Virot, E; Ponomarenko, A; Dehandschoewercker, É; Quéré, D; Clanet, C

    2016-02-01

    Data from storms suggest that the critical wind speed at which trees break is constant (≃42m/s), regardless of tree characteristics. We question the physical origin of this observation both experimentally and theoretically. By combining Hooke's law, Griffith's criterion, and tree allometry, we show that the critical wind speed indeed hardly depends on the height, diameter, and elastic properties of trees.

  4. SUSY breaking mediation by throat fields

    International Nuclear Information System (INIS)

    Bruemmer, F.; Hebecker, A.; Trapletti, M.

    2006-01-01

    We investigate, in the general framework of KKLT, the mediation of supersymmetry breaking by fields propagating in the strongly warped region of the compactification manifold ('throat fields'). Such fields can couple both to the supersymmetry breaking sector at the IR end of the throat and to the visible sector at the UV end. We model the supersymmetry breaking sector by a chiral superfield which develops an F term vacuum expectation value (also responsible for the uplift). It turns out that the mediation effect of vector multiplets propagating in the throat can compete with modulus-anomaly mediation. Moreover, such vector fields are naturally present as the gauge fields arising from isometries of the throat (most notably the SO(4) isometry of the Klebanov-Strassler solution). Their mediation effect is important in spite of their large 4d mass. The latter is due to the breaking of the throat isometry by the compact manifold at the UV end of the throat. The contribution from heavy chiral superfields is found to be subdominant

  5. Symmetry breaking and restoration in gauge theories

    International Nuclear Information System (INIS)

    Natale, A.A.

    A review is made of the utilization of the Higgs mechanism in spontaneous symmetry breaking. It is shown that such as ideas came from an analogy with the superconductivity phenomenological theory based on a Ginzburg-Landau lagrangean. The symmetry restoration through the temperature influence is studied. (L.C.) [pt

  6. Dynamical symmetry breaking in barium isotopes

    International Nuclear Information System (INIS)

    Rawat, Bir Singh; Chattopadhyay, P.K.

    1997-01-01

    The isotopes of Xe with mass numbers 124, 126, 128, 130 and the isotopes of barium with mass numbers 128, 130, 132, 134 were shown to correspond to the O(6) dynamical symmetry of IBM. In the investigation of the dynamical symmetry breaking in this region, the barium isotopes for departures from O(6) symmetry have been studied

  7. Variations on supersymmetry breaking and neutrino spectra

    International Nuclear Information System (INIS)

    Borzumati, F.; Hamaguchi, K.; Nomura, Y.; Yanagida, T.

    2000-01-01

    The problem of generating light neutrinos within supersymmetric models is discussed. It is shown that the hierarchy of scales induced by supersymmetry breaking can give rise to suppression factors of the correct order of magnitude to produce experimentally allowed neutrino spectra

  8. Unified gauge theories with spontaneous symmetry breaking

    International Nuclear Information System (INIS)

    MacDowell, S.W.

    1975-01-01

    Unified gauge theories with spontaneous symmetry breaking are studied with a view to renormalize quantum field theory. Georgi-Glashow and Weinberg-Salam models to unify weak and electromagnetic interactions are discussed in detail. Gauge theories of strong interactions are also considered [pt

  9. 125I-induced DNA double strand breaks: use in calibration of the neutral filter elution technique and comparison with X-ray induced breaks

    International Nuclear Information System (INIS)

    Radford, I.R.; Hodgson, G.S.

    1985-01-01

    The neutral filter elution assay, for measurement of DNA double strand breakage, has been calibrated using mouse L cells and Chinese hamster V79 cells labelled with [ 125 I]dUrd and then held at liquid nitrogen temperature to accumulate decays. The basis of the calibration is the observation that each 125 I decay, occurring in DNA, produces a DNA double strand break. Linear relationships between 125 I decays per cell and lethal lesions per cell (minus natural logarithm survival) and the level of elution, were found. Using the calibration data, it was calculated that the yield of DNA double strand breaks after X-irradiation of both cell types was from 6 to 9 x 10 -12 DNA double strand breaks per Gy per dalton of DNA, for doses greater than 6 Gy. Neutral filter elution and survival data for X-irradiated and 125 I-labelled cells suggested that the relationships between lethal lesions and DNA double strand breakage were significantly different for both cell types. An attempt was made to study the repair kinetics for 125 I-induced DNA double strand breaks, but was frustrated by the rapid DNA degradation which occurs in cells that have been killed by the freezing-thawing process. (author)

  10. Inductive line energy storage generator

    Energy Technology Data Exchange (ETDEWEB)

    Choi, P [Ecole Polytechnique, Palaiseau (France). Laboratoire de Physique des Milieux Ionises

    1997-12-31

    The inductive energy storage (IES) generator has long been considered to be the most efficient system for energy usage in large pulsed power system at the MA level. A number of parameters govern the efficiency of energy transfer between the storage capacitors and the load, and the level of current deliverable to the load. For high power system, the energy storage capacitors are arranged as a Marx generator. The primary constraints are the inductances in the various parts of the circuit, in particular, the upstream inductance between the Marx and the POS, and the downstream inductance between the POS and the load. This paper deals with the effect of replacing part of the upstream inductance with a transmission line and introduces the new concept of an inductive line for energy storage (ILES). Extensive parametric scans were carried out on circuit simulations to investigate the effect of this upstream transmission line. A model was developed to explain the operation of the ILES design based on the data obtained. Comparison with an existing IES generator shows that the ILES design offers a significant improvement in the maximum current and hence energy delivered to an inductive load. (author). 5 figs., 1 ref.

  11. Musculoskeletal injuries in break-dancers.

    Science.gov (United States)

    Cho, Chul Hyun; Song, Kwang Soon; Min, Byung Woo; Lee, Sung Moon; Chang, Hyuk Won; Eum, Dae Seup

    2009-11-01

    Since no epidemiologic studies have been reported about musculoskeletal injuries in break-dancers, there are no data on the rates and patterns of musculoskeletal injuries in this population that clinicians can use to find ways to decrease injury rate. We believe that the incidence of injuries in break-dancers is higher than assumed and that injury rates and patterns differ between professional and amateur dancers. Descriptive epidemiologic study. Of a total of 42 study subjects, 23 were professional dancers and 19 were amateur dancers. Injury frequency, site and type, along with the presence of supervised training, the use of protective devices and warm-up exercises done were recorded. Of the 42 study subjects, excluding two amateur dancers, 40 (95.2%) had had musculoskeletal injuries at more than one site. The mean number of sites per dancer was 4.60. The frequency of injury depended on the site and was as follows: wrist (69.0%), finger (61.9%), knee (61.9%), shoulder (52.4%), lumbar spine (50.0%), elbow (42.9%), cervical spine (38.1%), ankle (38.1%), foot (28.6%) and hip (16.7%). Sprain, strain and tendinitis were the most common injuries, accounting for the most cases. Of the 42 dancers, 13 (31%) had had fractures or dislocations. Eight (19.1%) learned break-dancing under supervised instruction, 17 (40.5%) used protective devices and 28 (66.7%) performed warm-up exercises before dancing. There were significant differences in age, dance career length, amount of dance training, mean number of injury sites and the presence of supervised training between professionals and amateurs (Pnature of the activities that result in both unusual and common injuries in break-dancers and educate them about safety. Careful screening, instruction and supervised training of break-dancers will help to prevent injuries.

  12. Breaking bad news among cancer physicians

    Directory of Open Access Journals (Sweden)

    Sami Ayed Alshammary

    2017-01-01

    Full Text Available Background: Breaking bad news to patients with cancer diagnosis is not an easy task for physicians. The diagnosis must be explicitly stated and understood, and prognosis must be well-discussed in the most gentle and comfortable manner. It is important that the disclosure is performed in a way that patients will not lose all hope and get very depressed, leading them to undergo an abrupt change of their outlook in life. Objective: The aim of this study was to explore the physicians' perceptions and perspectives of breaking bad news to cancer patients. Methods: A cross-sectional survey of all comprehensive cancer centre physicians currently working in a university teaching hospital in the Middle East was conducted from August to September 2016. Results: Sixty-eight percent responded to the survey. Eighty-four percent were comfortable with breaking bad news, and 70% had training in breaking bad news. Eighty-six percent of responders stated that patients should be told about their cancer. Almost 30% of the respondents stated that they would still disclose the diagnosis to patients even if it would be against the preference of the relatives. Nearly 61% said that they would only tell the details to the patients if asked while 67% of them disagreed that patients should be told about the diagnoses only if the relatives consent. About 51% of physicians wanted to discuss the bad news with the family members and patient together, whereas 24% stated that the patient alone should be involved in the discussion. Conclusion: Physicians face a dilemma when families do not wish the patient to know the cancer diagnosis and this highlights the necessity of taking into consideration the social circumstances in healthcare. When taking these into considerations, curriculum in the medical school must, therefore, be updated and must integrate the acquisition of skills in breaking bad news early in training.

  13. Quantum break-time of de Sitter

    Energy Technology Data Exchange (ETDEWEB)

    Dvali, Gia; Gómez, César; Zell, Sebastian, E-mail: georgi.dvali@physik.uni-muenchen.de, E-mail: cesar.gomez@uam.es, E-mail: sebastian.zell@campus.lmu.de [Arnold Sommerfeld Center, Ludwig-Maximilians-Universität, Theresienstraße 37, 80333 München (Germany)

    2017-06-01

    The quantum break-time of a system is the time-scale after which its true quantum evolution departs from the classical mean field evolution. For capturing it, a quantum resolution of the classical background—e.g., in terms of a coherent state—is required. In this paper, we first consider a simple scalar model with anharmonic oscillations and derive its quantum break-time. Next, following [1], we apply these ideas to de Sitter space. We formulate a simple model of a spin-2 field, which for some time reproduces the de Sitter metric and simultaneously allows for its well-defined representation as quantum coherent state of gravitons. The mean occupation number N of background gravitons turns out to be equal to the de Sitter horizon area in Planck units, while their frequency is given by the de Sitter Hubble parameter. In the semi-classical limit, we show that the model reproduces all the known properties of de Sitter, such as the redshift of probe particles and thermal Gibbons-Hawking radiation, all in the language of quantum S -matrix scatterings and decays of coherent state gravitons. Most importantly, this framework allows to capture the 1/ N -effects to which the usual semi-classical treatment is blind. They violate the de Sitter symmetry and lead to a finite quantum break-time of the de Sitter state equal to the de Sitter radius times N . We also point out that the quantum-break time is inversely proportional to the number of particle species in the theory. Thus, the quantum break-time imposes the following consistency condition: older and species-richer universes must have smaller cosmological constants. For the maximal, phenomenologically acceptable number of species, the observed cosmological constant would saturate this bound if our Universe were 10{sup 100} years old in its entire classical history.

  14. Quantum break-time of de Sitter

    Science.gov (United States)

    Dvali, Gia; Gómez, César; Zell, Sebastian

    2017-06-01

    The quantum break-time of a system is the time-scale after which its true quantum evolution departs from the classical mean field evolution. For capturing it, a quantum resolution of the classical background—e.g., in terms of a coherent state—is required. In this paper, we first consider a simple scalar model with anharmonic oscillations and derive its quantum break-time. Next, following [1], we apply these ideas to de Sitter space. We formulate a simple model of a spin-2 field, which for some time reproduces the de Sitter metric and simultaneously allows for its well-defined representation as quantum coherent state of gravitons. The mean occupation number N of background gravitons turns out to be equal to the de Sitter horizon area in Planck units, while their frequency is given by the de Sitter Hubble parameter. In the semi-classical limit, we show that the model reproduces all the known properties of de Sitter, such as the redshift of probe particles and thermal Gibbons-Hawking radiation, all in the language of quantum S-matrix scatterings and decays of coherent state gravitons. Most importantly, this framework allows to capture the 1/N-effects to which the usual semi-classical treatment is blind. They violate the de Sitter symmetry and lead to a finite quantum break-time of the de Sitter state equal to the de Sitter radius times N. We also point out that the quantum-break time is inversely proportional to the number of particle species in the theory. Thus, the quantum break-time imposes the following consistency condition: older and species-richer universes must have smaller cosmological constants. For the maximal, phenomenologically acceptable number of species, the observed cosmological constant would saturate this bound if our Universe were 10100 years old in its entire classical history.

  15. X-ray induced DNA double strand break production and repair in mammalian cells as measured by neutral filter elution

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, M O; Kohn, K W [National Institutes of Health, Bethesda, MD (USA)

    1979-10-01

    A neutral filter elution method was used for detecting DNA double strand breaks in mouse L1210 cells after X-ray. The assay detected the number of double strand breaks induced by as little as 1000 rad of X-ray. The rate of DNA elution through the filters under neutral conditions increased with X-ray dose. Certain conditions for deproteinization, pH, and filter type were shown to increase the assay's sensitivity. Hydrogen peroxide and Bleomycin also induced apparent DNA double strand breaks, although the ratios of double to single strand breaks varied from those produced by X-ray. The introduction of double strand cuts by HpA I restriction endonuclease in DNA lysed on filters resulted in a rapid rate of elution under neutral conditions, implying that the method can detect double strand breaks if they exist in the DNA. The eluted DNA banded with a double stranded DNA marker in cesium chloride. This evidence suggested that the assay detected DNA double strand breaks. L1210 cells were shown to rejoin most of the DNA double strand breaks induced by 5-10 krad of X-ray with a half-time of about 40 minutes. (author).

  16. Overview of Bearingless Induction Motors

    Directory of Open Access Journals (Sweden)

    Xiaodong Sun

    2014-01-01

    Full Text Available Bearingless induction motors combining functions of both torque generation and noncontact magnetic suspension together have attracted more and more attention in the past decades due to their definite advantages of compactness, simple structure, less maintenance, no wear particles, high rotational speed, and so forth. This paper overviews the key technologies of the bearingless induction motors, with emphasis on motor topologies, mathematical models, and control strategies. Particularly, in the control issues, the vector control, independent control, direct torque control, nonlinear decoupling control, sensorless control, and so forth are investigated. In addition, several possible development trends of the bearingless induction motors are also discussed.

  17. Early response of pressurized hot water in a pipe to a sudden break. Final report

    International Nuclear Information System (INIS)

    Alamgir, M.; Kan, C.Y.; Lienhard, J.H.

    1981-06-01

    Experimental and analytic studies that explain the details of early pressure variations during rapid depressurization in water-cooled reactors are presented as a means of assessing sudden break consequences in a coolant pipe. The report includes (1) a description of the experiment, (2) an analysis of the new bubble growth law for thermally controlled growth of vapor bubbles in an exponentially-varying pressure field, and (3) a review of previous studies and additional observations of blowdown behavior

  18. Suberoylanilide Hydroxyamic Acid Modification of Chromatin Architecture Affects DNA Break Formation and Repair

    International Nuclear Information System (INIS)

    Singh, Sheetal; Le Hongan; Shih, S.-J.; Ho, Bay; Vaughan, Andrew T.

    2010-01-01

    Purpose: Chromatin-modifying compounds that inhibit the activity of histone deacetylases have shown potency as radiosensitizers, but the action of these drugs at a molecular level is not clear. Here we investigated the effect of suberoylanilide hydroxyamic acid (SAHA) on DNA breaks and their repair and induction of rearrangements. Methods and Materials: The effect of SAHA on both clonogenic survival and repair was assessed using cell lines SCC-25, MCF7, and TK6. In order to study unique DNA double-strand breaks, anti-CD95 antibody was employed to introduce a DNA double-strand break at a known location within the 11q23 region. The effects of SAHA on DNA cleavage and rearrangements were analyzed by ligation-mediated PCR and inverse PCR, respectively. Results: SAHA acts as radiosensitizer at 1 μM, with dose enhancement factors (DEFs) at 10% survival of: SCC-25 - 1.24 ± 0.05; MCF7 - 1.16 ± 0.09 and TK6 - 1.17 ± 0.05, and it reduced the capacity of SCC-25 cells to repair radiation induced lesions. Additionally, SAHA treatment diffused site-specific fragmentation over at least 1 kbp in TK6 cells. Chromosomal rearrangements produced in TK6 cells exposed to SAHA showed a reduction in microhomology at the breakpoint between 11q23 and partner chromosomes. Conclusions: SAHA shows efficacy as a radiosensitizer at clinically obtainable levels. In its presence, targeted DNA strand breaks occur over an expanded region, indicating increased chromatin access. The rejoining of such breaks is degraded by SAHA when measured as rearrangements at the molecular level and rejoining that contributes to cell survival.

  19. Antibody induction versus placebo, no induction, or another type of antibody induction for liver transplant recipients

    DEFF Research Database (Denmark)

    Penninga, Luit; Wettergren, André; Wilson, Colin H

    2014-01-01

    . All 19 trials were with high risk of bias. Of the 19 trials, 16 trials were two-arm trials, and three trials were three-arm trials. Hence, we found 25 trial comparisons with antibody induction agents: interleukin-2 receptor antagonist (IL-2 RA) versus no induction (10 trials with 1454 participants....... Furthermore, serum creatinine was statistically significantly higher when T-cell specific antibody induction was compared with no induction (MD 3.77 μmol/L, 95% CI 0.33 to 7.21; low-quality evidence), as well as when polyclonal T-cell specific antibody induction was compared with no induction, but this small...... T-cell specific antibody induction, drug-related adverse events were less common among participants treated with interleukin-2 receptor antagonists (RR 0.23, 95% CI 0.09 to 0.63; low-quality evidence), but this was caused by the results from one trial, and trial sequential analysis could not exclude...

  20. Fault diagnosis of induction motors

    CERN Document Server

    Faiz, Jawad; Joksimović, Gojko

    2017-01-01

    This book is a comprehensive, structural approach to fault diagnosis strategy. The different fault types, signal processing techniques, and loss characterisation are addressed in the book. This is essential reading for work with induction motors for transportation and energy.

  1. B-L mediated SUSY breaking with radiative B-L symmetry breaking

    International Nuclear Information System (INIS)

    Kikuchi, Tatsuru; Kubo, Takayuki

    2008-01-01

    We explore a mechanism of radiative B-L symmetry breaking in analogous to the radiative electroweak symmetry breaking. The breaking scale of B-L symmetry is related to the neutrino masses through the see-saw mechanism. Once we incorporate the U(1) B-L gauge symmetry in SUSY models, the U(1) B-L gaugino, Z-tilde B-L appears, and it can mediate the SUSY breaking (Z-prime mediated SUSY breaking) at around the scale of 10 6 GeV. Then we find a links between the neutrino mass (more precisly the see-saw or B-L scale of order 10 6 GeV) and the Z-prime mediated SUSY breaking scale. It is also very interesting that the gluino at the weak scale becomes relatively light, and almost compressed mass spectra for the gaugino sector can be realized in this scenario, which is very interesting in scope of the LHC.

  2. Time to Reconsider Stem Cell Induction Strategies

    Directory of Open Access Journals (Sweden)

    Hans-Werner Denker

    2012-12-01

    Full Text Available Recent developments in stem cell research suggest that it may be time to reconsider the current focus of stem cell induction strategies. During the previous five years, approximately, the induction of pluripotency in somatic cells, i.e., the generation of so-called ‘induced pluripotent stem cells’ (iPSCs, has become the focus of ongoing research in many stem cell laboratories, because this technology promises to overcome limitations (both technical and ethical seen in the production and use of embryonic stem cells (ESCs. A rapidly increasing number of publications suggest, however, that it is now possible to choose instead other, alternative ways of generating stem and progenitor cells bypassing pluripotency. These new strategies may offer important advantages with respect to ethics, as well as to safety considerations. The present communication discusses why these strategies may provide possibilities for an escape from the dilemma presented by pluripotent stem cells (self-organization potential, cloning by tetraploid complementation, patenting problems and tumor formation risk.

  3. Dual realizations of dynamical symmetry breaking

    International Nuclear Information System (INIS)

    Dudas, Emilian; Papineau, Chloe

    2006-01-01

    We show the infrared equivalence between a recently proposed model containing a six dimensional scalar field with a four-dimensional localized Higgs type potential and the four-dimensional Nambu-Jona-Lasinio (NJL) model. In the dual NJL description, the fermions are localized at the origin of a large two-dimensional compact space. Due to a classical running effect above the compactification scale, the four-fermion coupling of the NJL model increases from the cutoff scale down to the compactification scale, providing the large Fermi coupling needed for the dynamical symmetry breaking. We also present a string theory embedding of our field-theory construction. On more general grounds, our results suggest that 4d models with dynamical symmetry breaking can be given a higher dimensional description in terms of field theories with nontrivial boundary conditions in the internal space

  4. Boost breaking in the EFT of inflation

    Energy Technology Data Exchange (ETDEWEB)

    Delacrétaz, Luca V.; Senatore, Leonardo [Stanford Institute for Theoretical Physics, Stanford University, Stanford, CA 94305 (United States); Noumi, Toshifumi, E-mail: lvd@stanford.edu, E-mail: tnoumi@phys.sci.kobe-u.ac.jp, E-mail: senatore@stanford.edu [Jockey Club Institute for Advanced Study, Hong Kong University of Science and Technology (Hong Kong)

    2017-02-01

    If time-translations are spontaneously broken, so are boosts. This symmetry breaking pattern can be non-linearly realized by either just the Goldstone boson of time translations, or by four Goldstone bosons associated with time translations and boosts. In this paper we extend the Effective Field Theory of Multifield Inflation to consider the case in which the additional Goldstone bosons associated with boosts are light and coupled to the Goldstone boson of time translations. The symmetry breaking pattern forces a coupling to curvature so that the mass of the additional Goldstone bosons is predicted to be equal to √2 H in the vast majority of the parameter space where they are light. This pattern therefore offers a natural way of generating self-interacting particles with Hubble mass during inflation. After constructing the general effective Lagrangian, we study how these particles mix and interact with the curvature fluctuations, generating potentially detectable non-Gaussian signals.

  5. Analysis of chiral symmetry breaking mechanism

    International Nuclear Information System (INIS)

    Guo, X. H.; Academia Sinica, Beijing; Huang, T.; CCAST

    1997-01-01

    The renormalization group invariant quark condensate μ is determined both from the consistent equation for quark condensate in the chiral limit and from the Schwinger-Dyson (SD) equation improved by the intermediate range QCD force singular like δ (q) which is associated with the gluon condensate. The solutions of μ in these two equations are consistent. The authors also obtain the critical strong coupling constant α c above which chiral symmetry breaks in these two approaches. The nonperturbative kernel of the SD equation makes α c smaller and μ bigger. An intuitive picture of the condensation above α c is discussed. In addition, with the help of the Slavnov-Taylor-Ward (STW) identity they derive the equations for the nonperturbative quark propagator from the SD equation in the presence of the intermediate range force and find that the intermediate-range force is also responsible for dynamical chiral symmetry breaking

  6. [Breaking bad news in clinical practice].

    Science.gov (United States)

    Herrera, Andrea; Ríos, Matías; Manríquez, José Manuel; Rojas, Gonzalo

    2014-10-01

    Breaking bad news is a complex task that requires multiple communication skills from health professionals. Clinical practice demands to communicate all type of bad news, from a diagnosis of cancer to adverse effects of a treatment. On the other hand, since the beginning of the health reform in 2003, the need to improve the quality of services was proposed, among which the concern about the rights and duties of patients stands out. Therefore, the health care provider-patient relationship becomes again the subject of discussion and study, and a topic of great importance for clinical work. We revise the consequences of breaking bad news for the patient and for the health care provider, as well as the current protocols available for this purpose. The importance of developing communication skills both for future health professionals as for those who currently work in the area is emphasized.

  7. Fractional Branes and Dynamical Supersymmetry Breaking

    CERN Document Server

    Franco, S; Saad, F; Uranga, Angel M; Franco, Sebastian; Hanany, Amihay; Saad, Fouad; Uranga, Angel M.

    2006-01-01

    We study the dynamics of fractional branes at toric singularities, including cones over del Pezzo surfaces and the recently constructed Y^{p,q} theories. We find that generically the field theories on such fractional branes show dynamical supersymmetry breaking, due to the appearance of non-perturbative superpotentials. In special cases, one recovers the known cases of supersymmetric infrared behaviors, associated to SYM confinement (mapped to complex deformations of the dual geometries, in the gauge/string correspondence sense) or N=2 fractional branes. In the supersymmetry breaking cases, when the dynamics of closed string moduli at the singularity is included, the theories show a runaway behavior (involving moduli such as FI terms or equivalently dibaryonic operators), rather than stable non-supersymmetric minima. We comment on the implications of this gauge theory behavior for the infrared smoothing of the dual warped throat solutions with 3-form fluxes, describing duality cascades ending in such field th...

  8. A break in the obesity epidemic?

    DEFF Research Database (Denmark)

    Visscher, T L S; Heitmann, B L; Rissanen, A

    2015-01-01

    Recent epidemiologic papers are presenting prevalence data suggesting breaks and decreases in obesity rates. However, before concluding that the obesity epidemic is not increasing anymore, the validity of the presented data should be discussed more thoroughly. We had a closer look into the litera......, focusing on trends in waist circumference rather than BMI leads to a less optimistic conclusion: the public health problem of obesity is still increasing.International Journal of Obesity advance online publication, 22 July 2014; doi:10.1038/ijo.2014.98....... into the literature presented in recent reviews to address the major potential biases and distortions, and to develop insights about how to interpret the presented suggestions for a potential break in the obesity epidemic. Decreasing participation rates, the use of reported rather than measured data and small sample...

  9. Selecting a model of supersymmetry breaking mediation

    International Nuclear Information System (INIS)

    AbdusSalam, S. S.; Allanach, B. C.; Dolan, M. J.; Feroz, F.; Hobson, M. P.

    2009-01-01

    We study the problem of selecting between different mechanisms of supersymmetry breaking in the minimal supersymmetric standard model using current data. We evaluate the Bayesian evidence of four supersymmetry breaking scenarios: mSUGRA, mGMSB, mAMSB, and moduli mediation. The results show a strong dependence on the dark matter assumption. Using the inferred cosmological relic density as an upper bound, minimal anomaly mediation is at least moderately favored over the CMSSM. Our fits also indicate that evidence for a positive sign of the μ parameter is moderate at best. We present constraints on the anomaly and gauge mediated parameter spaces and some previously unexplored aspects of the dark matter phenomenology of the moduli mediation scenario. We use sparticle searches, indirect observables and dark matter observables in the global fit and quantify robustness with respect to prior choice. We quantify how much information is contained within each constraint.

  10. Soft supersymmetry breaking in KKLT flux compactification

    International Nuclear Information System (INIS)

    Choi, K.; Falkowski, A.; Nilles, H.P.; Olechowski, M.

    2005-01-01

    We examine the structure of soft supersymmetry breaking terms in KKLT models of flux compactification with low energy supersymmetry. Moduli are stabilized by fluxes and nonperturbative dynamics while a de Sitter vacuum is obtained by adding supersymmetry breaking anti-branes. We discuss the characteristic pattern of mass scales in such a set-up as well as some features of 4D N=1 supergravity breakdown by anti-branes. Anomaly mediation is found to always give an important contribution and one can easily arrange for flavor-independent soft terms. In its most attractive realization, the modulus mediation is comparable to the anomaly mediation, yielding a quite distinctive sparticle spectrum. In addition, the axion component of the modulus/dilaton superfield dynamically cancels the relative CP phase between the contributions of anomaly and modulus mediation, thereby avoiding dangerous SUSY CP violation

  11. Qinshan NPP large break LOCA safety analysis

    International Nuclear Information System (INIS)

    Shi Guobao; Tang Jiahuan; Zhou Quanfu; Wang Yangding

    1997-01-01

    Qinshan NPP is the first nuclear power plant in the mainland of China, a 300 MW(e) two-loop PWR. Large break LOCA is the design-basis accident of Qinshan NPP. Based on available computer codes, the own analysis method which complies with Appendix k of 10 CFR 50 has been established. The RELAP4/MOD7 code is employed for the calculations of blowdown, refill and reflood phase of the RCS respectively. The CONTEMPT-LT/028 code is used for the containment pressure and temperature analysis. The temperature transient in the hot rod is calculated using the FRAP-6T code. Conservative initial and functional assumptions were adopted during Qinshan NPP large break LOCA analysis. The results of the analysis show the applicable acceptance criteria for the loss-of-coolant accident are met

  12. Isospin breaking in octet baryon mass splittings

    Energy Technology Data Exchange (ETDEWEB)

    Horsley, R. [Edinburgh Univ. (United Kingdom). School of Physics and Astronomy; Najjar, J. [Regensburg Univ. (Germany). Institut fuer Theoretische Physik; Nakamura, Y. [RIKEN Advanced Institute for Computational Science, Kobe, Hyogo (Japan); Pleiter, D. [Forschungszentrum Juelich (Germany). Juelich Supercomputer Centre; Rakow, P.E.L. [Liverpool Univ. (United Kingdom). Theoretical Physics Division; Schierholz, G. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Zanotti, J.M. [Adelaide Univ., SA (Australia). CSSM, School of Chemistry and Physics

    2012-06-15

    Using an SU(3) flavour symmetry breaking expansion in the quark mass, we determine the QCD component of the nucleon, Sigma and Xi mass splittings of the baryon octet due to up-down (and strange) quark mass differences in terms of the kaon mass splitting. Provided the average quark mass is kept constant, the expansion coefficients in our procedure can be determined from computationally cheaper simulations with mass degenerate sea quarks and partially quenched valence quarks. Both the linear and quadratic terms in the SU(3) flavour symmetry breaking expansion are considered; it is found that the quadratic terms only change the result by a few percent, indicating that the expansion is highly convergent.

  13. Electroweak symmetry breaking: Higgs/whatever

    International Nuclear Information System (INIS)

    Chanowitz, M.S.

    1989-01-01

    In the first of these two lectures the Higgs mechanism is reviewed in its most general form, which does not necessarily require the existence of Higgs bosons. The general consequences of the hypothesis that electroweak symmetry breaking is due to the Higgs mechanism are deduced just from gauge invariance and unitarity. In the second lecture the general properties are illustrated with three specific models: the Weinberg-Salam model, its minimal supersymmetric extension, and technicolor. The second lecture concludes with a discussion of the experiment signals for strong WW scattering, whose presence or absence will allow us to determine whether the symmetry breaking sector lies above or below 1 TeV. 57 refs

  14. Dynamics of Symmetry Breaking and Tachyonic Preheating

    CERN Document Server

    Felder, G; Greene, P B; Kofman, L A; Linde, Andrei D; Tkachev, Igor I; Felder, Gary; Garcia-Bellido, Juan; Greene, Patrick B.; Kofman, Lev; Linde, Andrei; Tkachev, Igor

    2001-01-01

    We reconsider the old problem of the dynamics of spontaneous symmetry breaking using 3d lattice simulations, and develop a theory of tachyonic preheating, which occurs due to the spinodal instability of the scalar field. Tachyonic preheating is so efficient that symmetry breaking typically completes within a single oscillation of the field distribution as it rolls towards the minimum of its effective potential. As an application of this theory we consider preheating in the hybrid inflation scenario, including SUSY-motivated F-term and D-term inflationary models. We show that preheating in hybrid inflation is typically tachyonic and the stage of oscillations of a homogeneous component of the scalar fields driving inflation ends after a single oscillation. Our results may also be relevant for the theory of the formation of disoriented chiral condensates in heavy ion collisions.

  15. Inductively coupled plasma source mass spectrometry

    International Nuclear Information System (INIS)

    Price Russ, G. III

    1993-01-01

    Inductively coupled plasma source mass spectrometry (ICP-MS) is a relatively new (5 y commercial availability) technique for simultaneously determining the concentration and isotopic composition of a large number of elements at trace levels. The principle advantages of ICP-MS are the ability to measure essentially all the metallic elements at concentrations as low as 1 part in 10 12 by weight, to analyse aqueous samples directly, to determine the isotopic composition of essentially all the metallic elements, and to analyse samples rapidly (minutes). The history of the development of ICP-MS and discussions of a variety of applications have been discussed in detail in Date and Gray (1988). Koppenaal (1988, 1990) has reviewed the ICP-MS literature. In that ICP-MS is a relatively new and still evolving technique, this chapter will discuss potential capability more than proven performance. (author). 24 refs

  16. RF induction plasma spheroidization of tungsten powders

    International Nuclear Information System (INIS)

    Gu Zhogntao; Ye Gaoying; Liu Chuandong; Tong Honghui

    2009-01-01

    Irregularly-shaped tungsten powders (average granular sizes of 512 μm) have been spheroidized by radio frequency (RF)induction plasma. The effects of feed rate, mode of material dispersion, particle size on spheroidization efficiency are investigated. Experimental results show that the spheroidization efficiency decreases rapidly when the feed rate increases to more than 95 g/min. Only 30% spheroidization efficiency is gained at the feed rate of 135.75 g/min. The spheroidization efficiency is also affected by the flow rate of carrier gas. When the flow rate of carrier gas is 0.12 m 3 /h, the dispersion effect is the best, and the spheroidization efficiency is almost 100%. The apparent density of tungsten powders increases a bit with the increase of spheroidization efficiency. And the particle size uniformity of spheroidized tungsten powders is in accordance with that of original powders. (authors)

  17. Automatic first-break picking using the instantaneous traveltime attribute

    KAUST Repository

    Saragiotis, Christos; Alkhalifah, Tariq Ali

    2012-01-01

    Picking the first breaks is an important step in seismic processing. The large volume of the seismic data calls for automatic and objective picking. We introduce a new automatic first-break picker, which uses specifically designed time windows

  18. On the character of scale symmetry breaking in gauge theories

    International Nuclear Information System (INIS)

    Gusijnin, V.P.; Kushnir, V.A.; Miransky, V.A.

    1988-01-01

    The problem of scale symmetry breaking in gauge theories is discussed. It is shown that the phenomenon of spontaneous breaking of scale symmetry in gauge theories is incompatible with the PCAAC dynamics. 12 refs

  19. Microwave-assisted rock breaking modelling and application

    CSIR Research Space (South Africa)

    Monchusi, B

    2012-10-01

    Full Text Available As part of the ongoing development of novel mining methods, the CSIR has developed alternative methods to break rocks. In this case, we show the application of microwave energy to break narrow tabular ore bodies....

  20. Break-even analysis in a nurse-managed center.

    Science.gov (United States)

    McBryde-Foster, Merry J

    2005-01-01

    The concept of break-even analysis as a financial assessment tool is defined and demonstrated in evaluation of a proposed nurse-managed center. The advantages of using break-even analysis during proposal development are explored.

  1. Breaking Bad Habits | NIH MedlinePlus the Magazine

    Science.gov (United States)

    ... of this page please turn Javascript on. Feature: Bad Habits Breaking Bad Habits: Why It's So Hard to Change Past Issues / ... News in Health ( http://newsinhealth.nih.gov/ ) Break Bad Habits Avoid temptations. If you always stop for a ...

  2. Breaking democracy with non renormalizable mass terms

    CERN Document Server

    Silva-Marcos, Joaquim I

    2001-01-01

    The exact democratic structure for the quark mass matrix, resulting from the action of the family symmetry group $A_{3L}\\times A_{3R}$, is broken by the vacuum expectation values of heavy singlet fields appearing in non renormalizable dimension 6 operators. Within this specific context of breaking of the family symmetry we formulate a very simple ansatz which leads to correct quark masses and mixings.

  3. Charge-independence-breaking in the triton

    International Nuclear Information System (INIS)

    Gloeckle, W.; Lee, T.S.H.; Wiringa, R.B.

    1990-01-01

    We find the effect of the observed charge-independence-breaking in 1 S 0 nucleon-nucleon scattering on the binding energy of the triton to be of order 80 keV. When corrections for this effect are made in an 18-channel momentum-space Faddeev calculation, we find the Paris and Argonne v 14 potentials triton binding energies that differ by only 20 keV

  4. Adjoint string breaking in the pseudoparticle approach

    International Nuclear Information System (INIS)

    Szasz, Christian; Wagner, Marc

    2008-01-01

    We apply the pseudoparticle approach to SU(2) Yang-Mills theory and perform a detailed study of the potential between two static charges for various representations. Whereas for charges in the fundamental representation we find a linearly rising confining potential, we clearly observe string breaking, when considering charges in the adjoint representation. We also demonstrate Casimir scaling and compute gluelump masses for different spin and parity. Numerical results are in qualitative agreement with lattice results.

  5. Missed retinal breaks in rhegmatogenous retinal detachment

    Directory of Open Access Journals (Sweden)

    Brijesh Takkar

    2016-12-01

    Full Text Available AIM: To evaluate the causes and associations of missed retinal breaks (MRBs and posterior vitreous detachment (PVD in patients with rhegmatogenous retinal detachment (RRD. METHODS: Case sheets of patients undergoing vitreo retinal surgery for RRD at a tertiary eye care centre were evaluated retrospectively. Out of the 378 records screened, 253 were included for analysis of MRBs and 191 patients were included for analysis of PVD, depending on the inclusion criteria. Features of RRD and retinal breaks noted on examination were compared to the status of MRBs and PVD detected during surgery for possible associations. RESULTS: Overall, 27% patients had MRBs. Retinal holes were commonly missed in patients with lattice degeneration while missed retinal tears were associated with presence of complete PVD. Patients operated for cataract surgery were significantly associated with MRBs (P=0.033 with the odds of missing a retinal break being 1.91 as compared to patients with natural lens. Advanced proliferative vitreo retinopathy (PVR and retinal bullae were the most common reasons for missing a retinal break during examination. PVD was present in 52% of the cases and was wrongly assessed in 16%. Retinal bullae, pseudophakia/aphakia, myopia, and horse shoe retinal tears were strongly associated with presence of PVD. Traumatic RRDs were rarely associated with PVD. CONCLUSION: Pseudophakic patients, and patients with retinal bullae or advanced PVR should be carefully screened for MRBs. Though Weiss ring is a good indicator of PVD, it may still be over diagnosed in some cases. PVD is associated with retinal bullae and pseudophakia, and inversely with traumatic RRD.

  6. Effective potential and chiral symmetry breaking

    International Nuclear Information System (INIS)

    Hochberg, David

    2010-01-01

    The nonequilibrium effective potential is calculated for the Frank model of spontaneous mirror-symmetry breaking in chemistry in which external noise is introduced to account for random environmental effects. The well-mixed limit, corresponding to negligible diffusion, and the case of diffusion in two space dimensions are studied in detail. White noise has a disordering effect in the former case, whereas in the latter case a phase transition occurs for external noise exceeding a critical intensity which racemizes the system.

  7. Enhanced breaking of heavy quark spin symmetry

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Feng-Kun, E-mail: fkguo@hiskp.uni-bonn.de [Helmholtz-Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universität Bonn, D-53115 Bonn (Germany); Meißner, Ulf-G., E-mail: meissner@hiskp.uni-bonn.de [Helmholtz-Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universität Bonn, D-53115 Bonn (Germany); Institute for Advanced Simulation, Institut für Kernphysik and Jülich Center for Hadron Physics, Forschungszentrum Jülich, D-52425 Jülich (Germany); Shen, Cheng-Ping, E-mail: shencp@ihep.ac.cn [School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191 (China)

    2014-11-10

    Heavy quark spin symmetry is useful to make predictions on ratios of decay or production rates of systems involving heavy quarks. The breaking of spin symmetry is generally of the order of O(Λ{sub QCD}/m{sub Q}), with Λ{sub QCD} the scale of QCD and m{sub Q} the heavy quark mass. In this paper, we will show that a small S- and D-wave mixing in the wave function of the heavy quarkonium could induce a large breaking in the ratios of partial decay widths. As an example, we consider the decays of the ϒ(10860) into the χ{sub bJ}ω(J=0,1,2), which were recently measured by the Belle Collaboration. These decays exhibit a huge breaking of the spin symmetry relation were the ϒ(10860) a pure 5S bottomonium state. We propose that this could be a consequence of a mixing of the S-wave and D-wave components in the ϒ(10860). Prediction on the ratio Γ(ϒ(10860)→χ{sub b0}ω)/Γ(ϒ(10860)→χ{sub b2}ω) is presented assuming that the decay of the D-wave component is dominated by the coupled-channel effects.

  8. Dormancy Breaking in Ormosia arborea Seeds

    Directory of Open Access Journals (Sweden)

    Edilma Pereira Gonçalves

    2011-01-01

    Full Text Available Ormosia arborea is a tree species planted in urban areas and used to restore degraded areas. Its seeds are dormant and propagation is difficult. This study compares different dormancy breaking methods and physiological seed quality and seedling production. The seeds were germinated in sand in the laboratory of the Universidade Estadual de Santa Cruz, Ilhéus, Bahia, Brazil. The following dormancy breaking treatments were applied: control (intact seeds, 100°C water immersion; boiling water immersion followed by 24 hours of soaking; scarification with number 100 and number 50 sandpaper opposite from root emergence; sulfuric acid immersion for 1 hour, 50, 45, and 30 minutes. Seed immersion in 100°C and boiling water did not break the dormancy. The study species showed a greater vigor of seedling when its seeds were submitted to treatments associated with tegument rupturing by sandpaper or sulfuric acid. On the other hand, seed scarification with sulfuric acid for 1 hour, 50, 45, and 30 minutes or sandpaper favored seed germination and vigor.

  9. Phenomenology of GUT-less Supersymmetry Breaking

    CERN Document Server

    Ellis, Jonathan Richard; Sandick, Pearl

    2007-01-01

    We study models in which supersymmetry breaking appears at an intermediate scale, M_{in}, below the GUT scale. We assume that the soft supersymmetry-breaking parameters of the MSSM are universal at M_{in}, and analyze the morphology of the constraints from cosmology and collider experiments on the allowed regions of parameter space as M_{in} is reduced from the GUT scale. We present separate analyses of the (m_{1/2},m_0) planes for tan(beta)=10 and tan(beta)=50, as well as a discussion of non-zero trilinear couplings, A_0. Specific scenarios where the gaugino and scalar masses appear to be universal below the GUT scale have been found in mirage-mediation models, which we also address here. We demand that the lightest neutralino be the LSP, and that the relic neutralino density not conflict with measurements by WMAP and other observations. At moderate values of M_{in}, we find that the allowed regions of the (m_{1/2},m_0) plane are squeezed by the requirements of electroweak symmetry breaking and that the ligh...

  10. A model for string-breaking in QCD

    International Nuclear Information System (INIS)

    Antonov, Dmitri; Del Debbio, Luigi; Di Giacomo, Adriano

    2003-01-01

    We present a model for string breaking based on the existence of chromoelectric flux tubes. We predict the form of the long-range potential and obtain an estimate of the string breaking length. A prediction is also obtained for the behaviour with temperature of the string breaking length near the deconfinement phase transition. We plan to use this model as a guide for a program of study of string breaking on the lattice. (author)

  11. Fast Times During Spring Breaks: Are Traffic Fatalities Another Consequence?

    OpenAIRE

    French, Michael; Gumus, Gulcin

    2014-01-01

    Every year in the United States, millions of college students travel for spring break, spending billions of dollars. We examine a potential adverse consequence of spring break that has received little attention in the literature - traffic safety. In particular, we estimate the impact of spring break season on fatal passenger vehicle crashes. Using daily county-level longitudinal data on traffic fatalities in popular spring break destinations from 1982-2011, we conduct separate analyses by age...

  12. Radiative breaking of cosmologically acceptable grand unified theories

    International Nuclear Information System (INIS)

    Gato, B.; Leon, J.; Quiros, M.

    1984-01-01

    We present a cosmologically acceptable grand unified model where the breaking of SU(5) proceeds through radiative corrections induced by supergravity soft-breaking terms. The breaking scale is determined by dimensional transmutation. The model is compatible with the radiative breaking of SU(2)sub(L)xU(1)sub(Y) which provides an experimentally accessible low energy particle spectrum and small top quark mass. (orig.)

  13. Hypnosis for induction of labour.

    Science.gov (United States)

    Nishi, Daisuke; Shirakawa, Miyako N; Ota, Erika; Hanada, Nobutsugu; Mori, Rintaro

    2014-08-14

    Induction of labour using pharmacological and mechanical methods can increase complications. Complementary and alternative medicine methods including hypnosis may have the potential to provide a safe alternative option for the induction of labour. However, the effectiveness of hypnosis for inducing labour has not yet been fully evaluated. To assess the effect of hypnosis for induction of labour compared with no intervention or any other interventions. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 January 2014), handsearched relevant conference proceedings, contacted key personnel and organisations in the field for published and unpublished references. All published and unpublished randomised controlled trials (RCTs) and cluster-RCTs of acceptable quality comparing hypnosis with no intervention or any other interventions, in which the primary outcome is to assess whether labour was induced. Two review authors assessed the one trial report that was identified (but was subsequently excluded). No RCTs or cluster-RCTs were identified from the search strategy. There was no evidence available from RCTs to assess the effect of hypnosis for induction of labour. Evidence from RCTs is required to evaluate the effectiveness and safety of this intervention for labour induction. As hypnosis may delay standard care (in case standard care is withheld during hypnosis), its use in induction of labour should be considered on a case-by-case basis.Future RCTs are required to examine the effectiveness and safety of hypnotic relaxation for induction of labour among pregnant women who have anxiety above a certain level. The length and timing of the intervention, as well as the staff training required, should be taken into consideration. Moreover, the views and experiences of women and staff should also be included in future RCTs.

  14. Breaking Waves on the Ocean Surface

    Science.gov (United States)

    Schwendeman, Michael S.

    In the open ocean, breaking waves are a critical mechanism for the transfer of energy, momentum, and mass between the atmosphere and the ocean. Despite much study, fundamental questions about wave breaking, such as what determines whether a wave will break, remain unresolved. Measurements of oceanic breakers, or "whitecaps," are often used to validate the hypotheses derived in simplified theoretical, numerical, or experimental studies. Real-world measurements are also used to improve the parameterizations of wave-breaking in large global models, such as those forecasting climate change. Here, measurements of whitecaps are presented using ship-based cameras, from two experiments in the North Pacific Ocean. First, a method for georectifying the camera imagery is described using the distant horizon, without additional instrumentation. Over the course of the experiment, this algorithm correctly identifies the horizon in 92% of images in which it is visible. In such cases, the calculation of camera pitch and roll is accurate to within 1 degree. The main sources of error in the final georectification are from mislabeled horizons due to clouds, rain, or poor lighting, and from vertical "heave" motions of the camera, which cannot be calculated with the horizon method. This method is used for correcting the imagery from the first experiment, and synchronizing the imagery from the second experiment to an onboard inertial motion package. Next, measurements of the whitecap coverage, W, are shown from both experiments. Although W is often used in models to represent whitecapping, large uncertainty remains in the existing parameterizations. The data show good agreement with recent measurements using the wind speed. Although wave steepness and dissipation are hypothesized to be more robust predictors of W, this is shown to not always be the case. Wave steepness shows comparable success to the wind parameterizations only when using a mean-square slope variable calculated over the

  15. Heating and thermal control of brazing technique to break contamination path for potential Mars sample return

    Science.gov (United States)

    Bao, Xiaoqi; Badescu, Mircea; Sherrit, Stewart; Bar-Cohen, Yoseph; Campos, Sergio

    2017-04-01

    The potential return of Mars sample material is of great interest to the planetary science community, as it would enable extensive analysis of samples with highly sensitive laboratory instruments. It is important to make sure such a mission concept would not bring any living microbes, which may possibly exist on Mars, back to Earth's environment. In order to ensure the isolation of Mars microbes from Earth's Atmosphere, a brazing sealing and sterilizing technique was proposed to break the Mars-to-Earth contamination path. Effectively, heating the brazing zone in high vacuum space and controlling the sample temperature for integrity are key challenges to the implementation of this technique. The break-thechain procedures for container configurations, which are being considered, were simulated by multi-physics finite element models. Different heating methods including induction and resistive/radiation were evaluated. The temperature profiles of Martian samples in a proposed container structure were predicted. The results show that the sealing and sterilizing process can be controlled such that the samples temperature is maintained below the level that may cause damage, and that the brazing technique is a feasible approach to breaking the contamination path.

  16. Induction of DNA–protein cross-links by ionizing radiation and their elimination from the genome

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, Toshiaki; Mitsusada, Yusuke [Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526 (Japan); Salem, Amir M.H. [Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526 (Japan); Department of Pathology, Medical Research Division, National Research Centre, El-Bohouth St., Dokki, Giza 12311 (Egypt); Shoulkamy, Mahmoud I. [Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526 (Japan); Department of Zoology, Biological Science Building, Faculty of Science, Minia University, Minia 61519 (Egypt); Sugimoto, Tatsuya [Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526 (Japan); Hirayama, Ryoichi; Uzawa, Akiko [Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), Chiba 263-8555 (Japan); Furusawa, Yoshiya [Development and Support Center, National Institute of Radiological Sciences (NIRS), Chiba 263-8555 (Japan); Ide, Hiroshi, E-mail: ideh@hiroshima-u.ac.jp [Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526 (Japan)

    2015-01-15

    Highlights: • Normoxic and hypoxic mouse tumors were irradiated with X-rays and C-ion beams. • DNA–protein cross-links (DPCs) and DNA double-strand breaks (DSBs) were analyzed. • C-ion beams produced more DPCs than did X-rays in normoxic and hypoxic tumor cells. • DPCs were eliminated from the genome much more slowly than DSBs. • Persisting DPCs may have deleterious effects on cells in conjunction with DSBs. - Abstract: Ionizing radiation produces various types of DNA lesions, such as base damage, single-strand breaks, double-strand breaks (DSBs), and DNA–protein cross-links (DPCs). Of these, DSBs are the most critical lesions underlying the lethal effects of ionizing radiation. With DPCs, proteins covalently trapped in DNA constitute strong roadblocks to replication and transcription machineries, and hence can be lethal to cells. The formation of DPCs by ionizing radiation is promoted in the absence of oxygen, whereas that of DSBs is retarded. Accordingly, the contribution of DPCs to the lethal events in irradiated cells may not be negligible for hypoxic cells, such as those present in tumors. However, the role of DPCs in the lethal effects of ionizing radiation remains largely equivocal. In the present study, normoxic and hypoxic mouse tumors were irradiated with X-rays [low linear energy transfer (LET) radiation] and carbon (C)-ion beams (high LET radiation), and the resulting induction of DPCs and DSBs and their removal from the genome were analyzed. X-rays and C-ion beams produced more DPCs in hypoxic tumors than in normoxic tumors. Interestingly, the yield of DPCs was slightly but statistically significantly greater (1.3- to 1.5-fold) for C-ion beams than for X-rays. Both X-rays and C-ion beams generated two types of DPC that differed according to their rate of removal from the genome. This was also the case for DSBs. The half-lives of the rapidly removed components of DPCs and DSBs were similar (<1 h), but those of the slowly removed components

  17. RAPID RESCUE: BREAKING THE MOLD OF ROUTINE CONTINGENCY RESPONSE FOR PERSONNEL RECOVERY

    Science.gov (United States)

    2016-10-23

    ultimately lead to timelier response and greater economy of force for an already critically strained Air Force core function. 1 INTRODUCTION...demographics, with a focus on the emerging near-peer powers such as Russia and Iran .9 Additionally, an important observation is made in that the DOD has...achieve economy of force. When an OPLAN calls for PR, a capability is requested rather than individual unit. The existing UTCs are too rigid and

  18. Sparticle spectrum and constraints in anomaly mediated supersymmetry breaking models

    International Nuclear Information System (INIS)

    Huitu, K.; Laamanen, J.; Pandita, P.N.

    2002-01-01

    We study in detail the particle spectrum in anomaly mediated supersymmetry breaking models in which supersymmetry breaking terms are induced by the super-Weyl anomaly. We investigate the minimal anomaly mediated supersymmetry breaking models, gaugino assisted supersymmetry breaking models, as well as models with additional residual nondecoupling D-term contributions due to an extra U(1) gauge symmetry at a high energy scale. We derive sum rules for the sparticle masses in these models which can help in differentiating between them. We also obtain the sparticle spectrum numerically, and compare and contrast the results so obtained for the different types of anomaly mediated supersymmetry breaking models

  19. Computational simulation of chromosome breaks in human liver

    International Nuclear Information System (INIS)

    Yang Jianshe; Li Wenjian; Jin Xiaodong

    2006-01-01

    An easy method was established for computing chromosome breaks in cells exposed to heavily charged particles. The cell chromosome break value by 12 C +6 ions was theoretically calculated, and was tested with experimental data of chromosome breaks by using a premature chromosome condensation technique. The theoretical chromosome break value agreed well with the experimental data. The higher relative biological effectiveness of the heavy ions was closely correlated to its physical characteristics. In addition, the chromosome break value can be predicted off line. (authors)

  20. DNA single-strand breaks during repair of uv damage in human fibroblasts and abnormalities of repair in xeroderma pigmentosum

    International Nuclear Information System (INIS)

    Fornace, A.J. Jr.; Kohn, K.W.; Kann, H.E. Jr.

    1976-01-01

    The method of DNA alkaline elution was applied to a study of the formation and resealing of DNA single-strand breaks after irradiation of human fibroblasts with ultraviolet light (UV). The general features of the results were consistent with current concepts of DNA excision repair, in that breaks appeared rapidly after uv, and resealed slowly in normal fibroblasts, whereas breaks did not appear in those cells of patients with xeroderma pigmentosum (XP) that are known to have defects in DNA repair synthesis. The appearance of breaks required a short post-uv incubation, consistent with the expected action of an endonuclease. Cells of the variant form of XP characterized by normal DNA repair synthesis exhibited normal production of breaks after uv, but were slower than normal cells in resealing these breaks. This difference was enhanced by caffeine. A model is proposed to relate this finding with a previously described defect in post-replication repair in these XP variant cells. DNA crosslinking appears to cause an underestimate in the measurement of DNA breakage after uv

  1. Induction interview form in EDH

    CERN Multimedia

    Information technology Department, AIS (Administrative Information Services) Group,

    2007-01-01

    As part of the efforts to rationalise administrative procedures, the IT and HR Departments have developed a new EDH form for induction interviews, which can be accessed using the link below. In accordance with Administrative Circular No. 2 ('Recruitment, Appointment and possible developments regarding the contractual position of Staff Members', Rev. 3), the work and training objectives to be achieved during the probation period shall be specified in writing to all new staff members during an induction interview. The interview shall take place between the new staff member and his supervisor within six weeks of him taking up his duties at the latest. https://edh.cern.ch/Document/MAPS/Induction (or from the EDH desktop, by clicking on 'Other Tasks' and going to the 'HR & Training' heading) Please note that this form is to be used exclusively for new staff members. A separate EDH form will be developed for fellows. Information technology Department, AIS (Administrative Information Services) Group Human...

  2. Induction interview form in EDH

    CERN Document Server

    Information technology Department, AIS (Administrative Information Services) Group

    2007-01-01

    As part of the efforts to rationalise administrative procedures, the IT and HR Departments have developed a new EDH form for induction interviews, which can be accessed using the link below. In accordance with Administrative Circular No. 2 ('Recruitment, Appointment and possible developments regarding the contractual position of Staff Members', Rev. 3), the work and training objectives to be achieved during the probation period shall be specified in writing to all new staff members during an induction interview. The interview shall take place between the new staff member and his supervisor within six weeks of his taking up his duties at the latest. https://edh.cern.ch/Document/MAPS/Induction1) (or from the EDH desktop, by clicking on 'Other Tasks' and going to the 'HR & Training' heading) Please note that this form is to be used exclusively for new staff members. A separate EDH form will be developed for fellows.Information technology Department, AIS (Administrative Information Services) Group Human Re...

  3. Breaking news dissemination in the media via propagation behavior based on complex network theory

    Science.gov (United States)

    Liu, Nairong; An, Haizhong; Gao, Xiangyun; Li, Huajiao; Hao, Xiaoqing

    2016-07-01

    The diffusion of breaking news largely relies on propagation behaviors in the media. The tremendous and intricate propagation relationships in the media form a complex network. An improved understanding of breaking news diffusion characteristics can be obtained through the complex network research. Drawing on the news data of Bohai Gulf oil spill event from June 2011 to May 2014, we constructed a weighted and directed complex network in which media are set as nodes, the propagation relationships as edges and the propagation times as the weight of the edges. The primary results show (1) the propagation network presents small world feature, which means relations among media are close and breaking news originating from any node can spread rapidly; (2) traditional media and official websites are the typical sources for news propagation, while business portals are news collectors and spreaders; (3) the propagation network is assortative and the group of core media facilities the spread of breaking news faster; (4) for online media, news originality factor become less important to propagation behaviors. This study offers a new insight to explore information dissemination from the perspective of statistical physics and is beneficial for utilizing the public opinion in a positive way.

  4. Best estimate small break LOCA analysis for KNGR SIS optimization

    International Nuclear Information System (INIS)

    Song, JIn Ho; Lim, Hong Sik; Bae, Kyoo Hwan; Lee, Joon

    1996-01-01

    The KNGR has an advanced ECCS design feature which employs four mechanically-separated SI trains where each train consisting of one HPSI pump and one SIT injects ECC water directly into the reactor vessel downcomer annulus. To demonstrate that the KNGR ECCS design features meet the EPRI ALWR requirements of no core uncovery for a break of up to 6 inch diameter, small break LOCA cases with various break sizes were analyzed using a best-estimate analytical procedure. Two kinds of break locations are considered: cold leg and DVI line breaks. It was observed that the KNGR ECCS design can tolerate a cold leg break of up to 10 inches with no core uncovery. However, since DVI line break with 6 inch diameter undergoes slight core uncovery, further investigation is required for KNGR SIS optimization

  5. Climate and floods still govern California levee breaks

    Science.gov (United States)

    Florsheim, J.L.; Dettinger, M.D.

    2007-01-01

    Even in heavily engineered river systems, climate still governs flood variability and thus still drives many levee breaks and geomorphic changes. We assemble a 155-year record of levee breaks for a major California river system to find that breaks occurred in 25% of years during the 20th Century. A relation between levee breaks and river discharge is present that sets a discharge threshold above which most levee breaks occurred. That threshold corresponds to small floods with recurrence intervals of ???2-3 years. Statistical analysis illustrates that levee breaks and peak discharges cycle (broadly) on a 12-15 year time scale, in time with warm-wet storm patterns in California, but more slowly or more quickly than ENSO and PDO climate phenomena, respectively. Notably, these variations and thresholds persist through the 20th Century, suggesting that historical flood-control effects have not reduced the occurrence or frequency of levee breaks. Copyright 2007 by the American Geophysical Union.

  6. Harmonic modeling of induction motors

    Energy Technology Data Exchange (ETDEWEB)

    Pedra, J.; Sainz, L.; Corcoles, F. [Department of Electrical Engineering, ETSEIB-UPC, Av. Diagonal 647, 08028 Barcelona (Spain)

    2006-07-15

    The paper proposes an induction motor model for the study of harmonic load flow in balanced and unbalanced conditions. The parameters of this model are obtained from motor manufacturer data and the positive- and negative-sequence equivalent circuits of the single- and double-cage models. An approximate harmonic model based on motor manufacturer data only is also proposed. In addition, the paper includes manufacturer data and the calculated parameters of 36 induction motors of different rated powers. This database is used to analyze the proposed models. (author)

  7. Induction linacs and pulsed power

    International Nuclear Information System (INIS)

    Caporaso, G.J.

    1995-01-01

    Progress in electronic power conversion technology is making possible a new class of induction linacs that can operate at extremely high repetition rates. Advances in insulator technology, pulse forming line design and switching may also lead to a new type of high current accelerator with accelerating gradients at least an order of magnitude greater than those attainable today. The evolution of the induction accelerator pulsed power system will be discussed along with some details of these emerging technologies which are at the frontiers of accelerator technology

  8. Timing of induction of labor.

    Science.gov (United States)

    Bacak, Stephen J; Olson-Chen, Courtney; Pressman, Eva

    2015-10-01

    Determining the optimal timing for induction of labor is critical in minimizing the risks to maternal and fetal health. While data are available to guide us in some clinical situations, such as hypertension and diabetes, many gaps in knowledge still exist in others, including cholestasis of pregnancy, fetal anomalies, and placental abruption. This review of the currently available literature assesses the risks and benefits of preterm and early term induction in a wide variety of maternal and fetal conditions. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Spontaneous Lorentz breaking at high energies

    International Nuclear Information System (INIS)

    Cheng, H.-C.; Luty, Markus A.; Mukohyama, Shinji; Thaler, Jesse

    2006-01-01

    Theories that spontaneously break Lorentz invariance also violate diffeomorphism symmetries, implying the existence of extra degrees of freedom and modifications of gravity. In the minimal model ('ghost condensation') with only a single extra degree of freedom at low energies, the scale of Lorentz violation cannot be larger than about M ∼ 100GeV due to an infrared instability in the gravity sector. We show that Lorentz symmetry can be broken at much higher scales in a non-minimal theory with additional degrees of freedom, in particular if Lorentz symmetry is broken by the vacuum expectation value of a vector field. This theory can be constructed by gauging ghost condensation, giving a systematic effective field theory description that allows us to estimate the size of all physical effects. We show that nonlinear effects become important for gravitational fields with strength Φ 1/2 ∼> g, where g is the gauge coupling, and we argue that the nonlinear dynamics is free from singularities. We then analyze the phenomenology of the model, including nonlinear dynamics and velocity-dependent effects. The strongest bounds on the gravitational sector come from either black hole accretion or direction-dependent gravitational forces, and imply that the scale of spontaneous Lorentz breaking is M ∼ 12 GeV, g 2 10 15 GeV). If the Lorentz breaking sector couples directly to matter, there is a spin-dependent inverse-square law force, which has a different angular dependence from the force mediated by the ghost condensate, providing a distinctive signature for this class of models

  10. Break spectrum analyses for small break loss of coolant accidents in a RESAR-3S Plant

    International Nuclear Information System (INIS)

    Fletcher, C.D.; Kullberg, C.M.

    1986-03-01

    A series of thermal-hydraulic analyses were performed to investigate phenomena occurring during small break loss-of-coolant-accident (LOCA) sequences in a RESAR-3S pressurized water reactor. The analysis included simulations of plant behavior using the TRAC-PF1 and RELAP5/MOD2 computer codes. Series of calculations were performed using both codes for different break sizes. The analyses presented here also served an audit function in that the results shown here were used by the US Nuclear Regulatory Commission (NRC) as an independent confirmation of similar analyses performed by Westinghouse Electric Company using another computer code. 10 refs., 62 figs., 14 tabs

  11. Electroweak Symmetry Breaking (3/3)

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    The focus of the lectures will be on the role of the Higgs boson in the mechanism of electroweak symmetry breaking, both in the Standard Model and in models of New Physics. In particular, I will discuss how a determination of its couplings to matter and gauge fields can give important information on the nature and origin of the Higgs boson. I will thus review the picture on Higgs couplings implied by the current experimental data and examine further interesting processes that can be measured in the future.

  12. Electroweak Symmetry Breaking (2/3)

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    The focus of the lectures will be on the role of the Higgs boson in the mechanism of electroweak symmetry breaking, both in the Standard Model and in models of New Physics. In particular, I will discuss how a determination of its couplings to matter and gauge fields can give important information on the nature and origin of the Higgs boson. I will thus review the picture on Higgs couplings implied by the current experimental data and examine further interesting processes that can be measured in the future.

  13. Electroweak Symmetry Breaking (1/3)

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    The focus of the lectures will be on the role of the Higgs boson in the mechanism of electroweak symmetry breaking, both in the Standard Model and in models of New Physics. In particular, I will discuss how a determination of its couplings to matter and gauge fields can give important information on the nature and origin of the Higgs boson. I will thus review the picture on Higgs couplings implied by the current experimental data and examine further interesting processes that can be measured in the future.

  14. Mechanically controllable break junctions for molecular electronics.

    Science.gov (United States)

    Xiang, Dong; Jeong, Hyunhak; Lee, Takhee; Mayer, Dirk

    2013-09-20

    A mechanically controllable break junction (MCBJ) represents a fundamental technique for the investigation of molecular electronic junctions, especially for the study of the electronic properties of single molecules. With unique advantages, the MCBJ technique has provided substantial insight into charge transport processes in molecules. In this review, the techniques for sample fabrication, operation and the various applications of MCBJs are introduced and the history, challenges and future of MCBJs are discussed. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Breaking the fault tree circular logic

    International Nuclear Information System (INIS)

    Lankin, M.

    2000-01-01

    Event tree - fault tree approach to model failures of nuclear plants as well as of other complex facilities is noticeably dominant now. This approach implies modeling an object in form of unidirectional logical graph - tree, i.e. graph without circular logic. However, genuine nuclear plants intrinsically demonstrate quite a few logical loops (circular logic), especially where electrical systems are involved. This paper shows the incorrectness of existing practice of circular logic breaking by elimination of part of logical dependencies and puts forward a formal algorithm, which enables the analyst to correctly model the failure of complex object, which involves logical dependencies between system and components, in form of fault tree. (author)

  16. Leak before break experience in CANDU reactors

    International Nuclear Information System (INIS)

    Price, E.G.; Moan, G.D.; Coleman, C.E.

    1988-04-01

    The paper describes how the requirements for Leak-Before-Break are met in CANDU reactors. The requirements are based on operational and laboratory experience. After the onset of leakage in a fuel channel from a delayed hydride crack, time is available to the operator to take action before the crack grows to an unstable length. The time available is calculated using different models which use crack growth data from small specimen tests. When the results from crack growth behaviour experiments, carried out on components removed from reactor are used in the model, the time available for operator response is about 100 hours

  17. SU(3) flavour breaking and baryon structure

    Energy Technology Data Exchange (ETDEWEB)

    Cooke, A.N.; Horsley, R. [Edinburgh Univ. (United Kingdom). School of Physics and Astronomy; Nakamura, Y. [RIKEN Advanced Institute for Computational Science, Kobe, Hyogo (Japan); Pleiter, D. [Forschungszentrum Juelich GmbH (Germany). Juelich Supercomputing Centre (JSC); Regensburg Univ. (Germany). Institut fuer Theoretische Physik; Rakow, P.E.L. [Liverpool Univ. (United Kingdom). Theoretical Physics Div.; Shanahan, P.; Zanotti, J.M. [Adelaide Univ., SA (Australia). CSSM, School of Chemistry and Physics; Schierholz, G. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Stueben, H. [Hamburg Univ. (Germany). Regionales Rechenzentrum; Collaboration: QCDSF/UKQCD Collaboration

    2013-11-15

    We present results from the QCDSF/UKQCD collaboration for hyperon electromagnetic form factors and axial charges obtained from simulations using N{sub f}=2+1 flavours of O(a)-improved Wilson fermions. We also consider matrix elements relevant for hyperon semileptonic decays. We find flavour-breaking effects in hyperon magnetic moments which are consistent with experiment, while our results for the connected quark spin content indicates that quarks contribute more to the spin of the {Xi} baryon than they do to the proton.

  18. Electroweak symmetry breaking beyond the Standard Model

    International Nuclear Information System (INIS)

    Bhattacharyya, Gautam

    2012-01-01

    In this paper, two key issues related to electroweak symmetry breaking are addressed. First, how fine-tuned different models are that trigger this phenomenon? Second, even if a light Higgs boson exists, does it have to be necessarily elementary? After a brief introduction, the fine-tuning aspects of the MSSM, NMSSM, generalized NMSSM and GMSB scenarios shall be reviewed, then the little Higgs, composite Higgs and the Higgsless models shall be compared. Finally, a broad overview will be given on where we stand at the end of 2011. (author)

  19. Phenomenology of flavor-mediated supersymmetry breaking

    International Nuclear Information System (INIS)

    Kaplan, D. Elazzar; Kribs, Graham D.

    2000-01-01

    The phenomenology of a new economical supersymmetric model that utilizes dynamical supersymmetry breaking and gauge mediation for the generation of the sparticle spectrum and the hierarchy of fermion masses is discussed. Similarities between the communication of supersymmetry breaking through a messenger sector and the generation of flavor using the Froggatt-Nielsen (FN) mechanism are exploited, leading to the identification of vector-like messenger fields with FN fields and the messenger U(1) as a flavor symmetry. An immediate consequence is that the first and second generation scalars acquire flavor-dependent masses, but do not violate flavor changing neutral current bounds since their mass scale, consistent with ''effective supersymmetry,'' is of order 10 TeV. We define and advocate a ''minimal flavor-mediated model'' (MFMM), recently introduced in the literature, which successfully accommodates the small flavor-breaking parameters of the standard model using order 1 couplings and ratios of flavon field VEVs. The mediation of supersymmetry breaking occurs via two-loop logarithm-enhanced gauge-mediated contributions, as well as several one-loop and two-loop Yukawa-mediated contributions for which we provide analytical expressions. The MFMM is parametrized by a small set of masses and couplings, with values restricted by several model constraints and experimental data. Full two-loop renormalization group evolution is performed, correctly taking into account the negative two-loop gauge contributions from heavy first and second generations. Electroweak symmetry is radiatively broken with the value of μ determined by matching to the Z mass. The weak scale spectrum is generally rather heavy, except for the lightest Higgs boson, the lightest stau, the lightest chargino, the lightest two neutralinos, and of course a very light gravitino. The next-to-lightest sparticle always has a decay length that is larger than the scale of a detector, and is either the lightest stau

  20. Density Functional Simulation of a Breaking Nanowire

    DEFF Research Database (Denmark)

    Nakamura, A.; Brandbyge, Mads; Hansen, Lars Bruno

    1999-01-01

    to a specific number of eigenchannels. The transitions between plateaus can be abrupt in connection with structural rearrangements or extend over a few a of elongation. The interplay between conductance modes and structural deformation is discussed by means of the eigenchannel transmission probabilities.......We study the deformation and breaking of an atomic-sized sodium wire using density functional simulations. The wire deforms through sudden atomic rearrangements and smoother atomic displacements. The conductance of the wire exhibits plateaus at integer values in units of 2e(2)/h corresponding...

  1. Cosmoparticle physics of family symmetry breaking

    International Nuclear Information System (INIS)

    Khlopov, M.Yu.

    1993-07-01

    The foundations of both particle theory and cosmology are hidden at super energy scale and can not be tested by direct laboratory means. Cosmoparticle physics is developed to probe these foundations by the proper combination of their indirect effects, thus providing definite conclusions on their reliability. Cosmological and astrophysical tests turn to be complementary to laboratory searches of rare processes, induced by new physics, as it can be seen in the case of gauge theory of broken symmetry of quark and lepton families, ascribing to the hierarchy of the horizontal symmetry breaking the observed hierarchy of masses and the mixing between quark and lepton families. 36 refs

  2. Several ways of breaking the colour symmetry

    International Nuclear Information System (INIS)

    Krolikowski, W.

    1975-01-01

    We discuss some cases of colour-symmetry breaking and its implications for quark binding by one-gluon-exchange forces. We pay special attention to the case, where colour-isospin and colour-hypercharge subsymmetries are preserved. Then, the ω-PHI-like mixing of colour-nonet components 0 and 8 leads to a Zweig-type approximate selection rule for decays of PHI-like meson = antiqsub(B)qsub(B)(qsub(B) is the '' blue'' quark) into ordinary mesons (and photons). (author)

  3. Study on Induction Heating Coil for Uniform Mold Cavity Surface Heating

    OpenAIRE

    Yu-Ting Sung; Sheng-Jye Hwang; Huei-Huang Lee; Durn-Yuan Huang

    2014-01-01

    Recently, energy saving is one of the important issues for polymer processing industry. Electromagnetic induction heating has many advantages such as fast heating and low energy consumption. Previous studies using electromagnetic induction heating for rapid tool heating have indicated that the temperature uniformity on a cavity surface is not easy to be achieved. In this paper, two different coils were used for heating uniform 7 mm thick hot work tool steel (JIS SKD61) surface. One is a four-...

  4. An induction heating device using planar coil with high amplitude alternating magnetic fields for magnetic hyperthermia.

    Science.gov (United States)

    Wu, Zuhe; Zhuo, Zihang; Cai, Dongyang; Wu, Jian'an; Wang, Jie; Tang, Jintian

    2015-01-01

    Induction heating devices using the induction coil and magnetic nanoparticles (MNPs) are the way that the magnetic hyperthermia is heading. To facilitate the induction heating of in vivo magnetic nanoparticles in hyperthermia experiments on large animals. An induction heating device using a planar coil was designed with a magnetic field frequency of 328 kHz. The coil's magnetic field distribution and the device's induction heating performance on different concentrations of magnetic nanoparticles were measured. The alternating magnetic field produced in the axis position 165 mm away from the coil center is 40 Gs in amplitude; magnetic nanoparticles with a concentration higher than 80 mg. mL-1 can be heated up rapidly. Our results demonstrate that the device can be applied not only to in vitro and in small animal experiments of magnetic hyperthermia using MNPs, but also in large animal experiments.

  5. DNA Double-Strand Break Rejoining in Complex Normal Tissues

    International Nuclear Information System (INIS)

    Ruebe, Claudia E.; Dong, Xiaorong; Kuehne, Martin; Fricke, Andreas; Kaestner, Lars; Lipp, Peter; Ruebe, Christian

    2008-01-01

    Purpose: The clinical radiation responses of different organs vary widely and likely depend on the intrinsic radiosensitivities of their different cell populations. Double-strand breaks (DSBs) are the most deleterious form of DNA damage induced by ionizing radiation, and the cells' capacity to rejoin radiation-induced DSBs is known to affect their intrinsic radiosensitivity. To date, only little is known about the induction and processing of radiation-induced DSBs in complex normal tissues. Using an in vivo model with repair-proficient mice, the highly sensitive γH2AX immunofluorescence was established to investigate whether differences in DSB rejoining could account for the substantial differences in clinical radiosensitivity observed among normal tissues. Methods and Materials: After whole body irradiation of C57BL/6 mice (0.1, 0.5, 1.0, and 2.0 Gy), the formation and rejoining of DSBs was analyzed by enumerating γH2AX foci in various organs representative of both early-responding (small intestine) and late-responding (lung, brain, heart, kidney) tissues. Results: The linear dose correlation observed in all analyzed tissues indicated that γH2AX immunofluorescence allows for the accurate quantification of DSBs in complex organs. Strikingly, the various normal tissues exhibited identical kinetics for γH2AX foci loss, despite their clearly different clinical radiation responses. Conclusion: The identical kinetics of DSB rejoining measured in different organs suggest that tissue-specific differences in radiation responses are independent of DSB rejoining. This finding emphasizes the fundamental role of DSB repair in maintaining genomic integrity, thereby contributing to cellular viability and functionality and, thus, tissue homeostasis

  6. Accelerated heavy ions induced DNA double-strand breaks in yeast cells

    International Nuclear Information System (INIS)

    Akpa, T.C.

    1993-01-01

    Yeast cells of strain cerevisiae, were irradiated with monoenergetic heavy ions, X-rays and α particles and assayed for DNA double-strand breaks and cell survival. The method of neutral sucrose gradient velocity sedimentation was used for all heavy-ion experiments because it is a well established technique.The method of pulsed-field gel electrophoresis was used for X-rays, α particles and argon ions. Results show that within the range of LET of the particles used (300 - 10 5 KeV/μm) the induction cross-section for DNA double-strand break is constant between 300 and around 7000 KeV/μm and increases at higher LET values. The inactivation cross-section follow the same trend. The DSB-induction and inactivation cross-section was shown to be linearly related with a slope of (1.01±0.15)/109 gmol-i. The RBE for DSB -induced decreases with LET and tails off at high LET values also. These results when compared with results from literature shows that the trend of induction is first monotonic rise of rate of DSB-induction up to 100keV/μm, followed by a plateau and a further rise which is due to increased effect of energetic γ-rays formed as shown for survival studies and predicted is possible to separate the cell DNA contents into 13 to 15 chromosome bands. The relative decrease in DNA content of the first band as determined by ethidium bromide-UV fluorescence decreases exponentially. The cross-section for DSB-induction determined by this method are (9.8±0.01)dsb/10 12 gmol - 1 Gy - 1, for 80 kV X-rays in haploid 211 yeast strain; (0.04+0.003)dsb/109gmol - 1μm 2 for Am-radioisotope α particles in haploid cells, (0.184±0.034) dsb/10 9 gmol - 1μm 2 in diploid 211*B cells and (0.55±0.04) dsb/10 9 gmol - 1μm 2 for 7MeV Argon ion in the diploid cells. The values are comparable to those obtained with velocity sedimentation technique. However, the reason for the low value obtained for a particle induced DSB in haploid cells is not clear

  7. DNA strand breaking and rejoining in response to ultraviolet light in normal human and xeroderma pigmentosum cells

    International Nuclear Information System (INIS)

    Dingman, C.W.; Kakunaga, T.

    1976-01-01

    A description is given of a reproducible technique for measuring DNA strand breaking and rejoining in cells after treatment with U.V.-light. Results obtained with normal human cells, xeroderma pigmentosum cells (XP, complementation group A) and XP variant cells suggested that all three of these cell-types can carry out single-strand incision with equal rapidity. However, the breaks so induced appeared to be only slowly rejoined in the XP variant cells and rejoined not at all in XP complementation group A cells. Furthermore, parental strand rejoining was inhibited by caffeine in XP variant cells but not in normal cells. (author)

  8. Radiation Induced G2 Chromatic Break and Repairs Kinetics in Human Lymphoblastoid Cells

    International Nuclear Information System (INIS)

    Seong, Jin Sil

    1993-01-01

    In understanding radiosensitivity a new concept of inherent radiosensitivity based on individuality and heterogeneity within a population has recently beer explored. There has been some discussion of possible mechanism underlying differences in radiosensitivity between cells. Ataxia telangiectasia(AT), a rare autosomal recessive genetic disorder, is characterized by hypersensitivity to lonizing radiation and other DNA damaging agents at the cellular level. There have been a lot of efforts to describe the cause of this hypersensitivity to radiation. At the cellular level, chromosome repair kinetics study would be an appropriate approach. The purpose of this study was to better understand radiosensitivity in an approach to investigate kinetics of induction and repair of G2 chromatic breaks using normal, AT heterozygous(ATH), and AT homozygous lymphoblastoid cell lines. In an attempt to estimate initial damage, 9-β-D-arabinosyl-2-fluoroadenine, an inhibitor of DNA synthesis and repair, was used in this study. It was found from this study that radiation induces higher chromatid breaks in AT than in normal and ATH cells. There was no significant differences of initial chromatid breaks between normal and ATH cells. Repair kinetics was the same for all. So the higher level of breaks in AT G2 cells is thought to be a reflection of the increased initial damage. The amount of initial damage correlated well with survival fraction at 2 Gy of cell survival curve following radiation. Therefore, the difference of radiosensitivity in terms of G2 chromosomal sensitivity is thought to result from the difference of initial damage

  9. Hyperscaling violation and electroweak symmetry breaking

    Energy Technology Data Exchange (ETDEWEB)

    Elander, Daniel, E-mail: pelander@purdue.edu [Department of Physics, Purdue University, 525 Northwestern Avenue, West Lafayette, IN 47907-2036 (United States); Lawrance, Robert; Piai, Maurizio [Department of Physics, College of Science, Swansea University, Singleton Park, Swansea, Wales (United Kingdom)

    2015-08-15

    We consider a class of simplified models of dynamical electroweak symmetry breaking built in terms of their five-dimensional weakly-coupled gravity duals, in the spirit of bottom-up holography. The sigma-model consists of two abelian gauge bosons and one real, non-charged scalar field coupled to gravity in five dimensions. The scalar potential is a simple exponential function of the scalar field. The background metric resulting from solving the classical equations of motion exhibits hyperscaling violation, at least at asymptotically large values of the radial direction. We study the spectrum of scalar composite states of the putative dual field theory by fluctuating the sigma-model scalars and gravity, and discuss in which cases we find a parametrically light scalar state in the spectrum. We model the spontaneous breaking of the (weakly coupled) gauge symmetry to the diagonal subgroup by the choice of IR boundary conditions. We compute the mass spectrum of spin-1 states, and the precision electroweak parameter S as a function of the hyperscaling coefficient. We find a general bound on the mass of the lightest spin-1 resonance, by requiring that the indirect bounds on the precision parameters be satisfied, that implies that precision electroweak physics excludes the possibility of a techni-rho meson with mass lighter than several TeV.

  10. Flavor symmetry breaking and meson masses

    International Nuclear Information System (INIS)

    Bhagwat, Mandar S.; Roberts, Craig D.; Chang Lei; Liu Yuxin; Tandy, Peter C.

    2007-01-01

    The axial-vector Ward-Takahashi identity is used to derive mass formulas for neutral pseudoscalar mesons. Flavor symmetry breaking entails nonideal flavor content for these states. Adding that the η ' is not a Goldstone mode, exact chiral-limit relations are developed from the identity. They connect the dressed-quark propagator to the topological susceptibility. It is confirmed that in the chiral limit the η ' mass is proportional to the matrix element which connects this state to the vacuum via the topological susceptibility. The implications of the mass formulas are illustrated using an elementary dynamical model, which includes an Ansatz for that part of the Bethe-Salpeter kernel related to the non-Abelian anomaly. In addition to the current-quark masses, the model involves two parameters, one of which is a mass-scale. It is employed in an analysis of pseudoscalar- and vector-meson bound-states. While the effects of SU(N f =2) and SU(N f =3) flavor symmetry breaking are emphasized, the five-flavor spectra are described. Despite its simplicity, the model is elucidative and phenomenologically efficacious; e.g., it predicts η-η ' mixing angles of ∼-15 deg. and π 0 -η angles of ∼1 deg

  11. Dynamical supersymmetry breaking and gauge anomalies

    International Nuclear Information System (INIS)

    Zhang, H.

    1991-01-01

    Some aspects of supersymmetric gauge theories are discussed. It is shown that dynamical supersymmetry breaking does not occur in supersymmetric QED in higher dimensions. The cancellation of both local (perturbative) and global (non-perturbative) gauge anomalies are also discussed in supersymmetric gauge theories. We argue that there is no dynamical supersymmetry breaking in higher dimensions in any supersymmetric gauge theories free of gauge anomalies. It is also shown that for supersymmetric gauge theories in higher dimensions with a compact connected simple gauge group, when the local anomaly-free condition is satisfied, there can be at most a possible Z 2 global gauge anomaly in extended supersymmetric SO(10) (or spin (10)) gauge theories in D=10 dimensions containing additional Weyl fermions in a spinor representation of SO(10) (or spin (10)). In four dimensions with local anomaly-free condition satisfied, the only possible global gauge anomalies in supersymmetric gauge theories are Z 2 global gauge anomalies for extended supersymmetric SP(2N) (N=rank) gauge theories containing additional Weyl fermions in a representation of SP(2N) with an odd 2nd-order Dynkin index. (orig.)

  12. Large-field inflation and supersymmetry breaking

    International Nuclear Information System (INIS)

    Buchmueller, Wilfried; Wieck, Clemens; Dudas, Emilian; Heurtier, Lucien; Ecole Polytechnique, Palaiseau

    2014-07-01

    Large-field inflation is an interesting and predictive scenario. Its non-trivial embedding in supergravity was intensively studied in the recent literature, whereas its interplay with supersymmetry breaking has been less thoroughly investigated. We consider the minimal viable model of chaotic inflation in supergravity containing a stabilizer field, and add a Polonyi field. Furthermore, we study two possible extensions of the minimal setup. We show that there are various constraints: first of all, it is very hard to couple an O'Raifeartaigh sector with the inflaton sector, the simplest viable option being to couple them only through gravity. Second, even in the simplest model the gravitino mass is bounded from above parametrically by the inflaton mass. Therefore, high-scale supersymmetry breaking is hard to implement in a chaotic inflation setup. As a separate comment we analyze the simplest chaotic inflation construction without a stabilizer field, together with a supersymmetrically stabilized Kaehler modulus. Without a modulus, the potential of such a model is unbounded from below. We show that a heavy modulus cannot solve this problem.

  13. Supersymmetry breaking in 4D string theory

    International Nuclear Information System (INIS)

    De la Macorra, A.; Ross, G.G.

    1995-01-01

    We construct a (locally supersymmetric) four-fermion effective lagrangian description of the strong binding effects responsible for the formation of a gaugino condensate, extending the analysis to include the multiple moduli of orbifold compactification. Using this to estimate the binding we find that supersymmetry is broken and a phenomenologically realistic value for the gravitino mass and gauge coupling constant at the unification scale with only one gaugino condensate may be obtained. The main source for supersymmetry breaking is the VEV of the auxiliary field of the dilaton h s (i.e. h S >>h T , where T are moduli fields). By studying the scalar potential we find either that the vacuum expectation values of the moduli have a common value related to the vacuum expectation value of the dilaton or that they take the values of the dual invariant points. A squeezed orbifold can thus naturally be obtained, allowing for the possibility of minimal string unification. We include chiral matter fields and derive the scalar potential up to one-loop level. The one-loop potential is responsible for stabilising the scalar potential for vanishing vacuum expectation values of the chiral matter fields. We then calculate the soft supersymmetry breaking parameters in the visible sector. Finally we show that with a suitable choice of superpotential it is possible to cancel the cosmological constant while having supersymmetry broken. ((orig.))

  14. Inductive acquisition of expert knowledge

    Energy Technology Data Exchange (ETDEWEB)

    Muggleton, S.H.

    1986-01-01

    Expert systems divide neatly into two categories: those in which (1) the expert decisions result in changes to some external environment (control systems), and (2) the expert decisions merely seek to describe the environment (classification systems). Both the explanation of computer-based reasoning and the bottleneck (Feigenbaum, 1979) of knowledge acquisition are major issues in expert-systems research. The author contributed to these areas of research in two ways: 1. He implemented an expert-system shell, the Mugol environment, which facilitates knowledge acquisition by inductive inference and provides automatic explanation of run-time reasoning on demand. RuleMaster, a commercial version of this environment, was used to advantage industrially in the construction and testing of two large classification systems. 2. He investigated a new techniques called 'sequence induction' that can be used in construction of control systems. Sequence induction is based on theoretical work in grammatical learning. He improved existing grammatical learning algorithms as well as suggesting and theoretically characterizing new ones. These algorithms were successfully applied to acquisition of knowledge for a diverse set of control systems, including inductive construction of robot plans and chess end-gam strategies.

  15. Phonotactics in inductive logic programming

    NARCIS (Netherlands)

    Nerbonne, J.; Konstantopoulos, S.; Klopotek, M.A.; Wierzchon, S.T.; Trojanowski, K.

    2004-01-01

    We examine the results of applying inductive logic programming (ILP) to a relatively simple linguistic task, that of recognizing monosyllables in one language. ILP is suited to linguistic problems given linguists' preference for formulating their theories in discrete rules, and because of ILP's

  16. Inductive logic on conceptual spaces

    NARCIS (Netherlands)

    Sznajder, Marta

    2017-01-01

    This thesis investigates the question of how conceptual frameworks influence inductive reasoning. A conceptual framework is a collection of concepts used for a particular purpose; we can think of it as a semantic environment in which observations, or evidence, are recorded, and beliefs are formed

  17. Teaching Inductive Reasoning with Puzzles

    Science.gov (United States)

    Wanko, Jeffrey J.

    2017-01-01

    Working with language-independent logic structures can help students develop both inductive and deductive reasoning skills. The Japanese publisher Nikoli (with resources available both in print and online) produces a treasure trove of language-independent logic puzzles. The Nikoli print resources are mostly in Japanese, creating the extra…

  18. 'Jet breaks' and 'missing breaks' in the X-Ray afterglow of Gamma Ray Bursts

    CERN Document Server

    Dado, Shlomo; De Rújula, Alvaro

    2008-01-01

    The X-ray afterglows (AGs) of Gamma-Ray Bursts (GRBs) and X-Ray Flashes (XRFs) have, after the fast decline phase of their prompt emission, a temporal behaviour varying between two extremes. A large fraction of these AGs has a 'canonical' light curve which, after an initial shallow-decay 'plateau' phase, 'breaks smoothly' into a fast power-law decline. Very energetic GRBs, contrariwise, appear not to have a 'break', their AG declines like a power-law from the start of the observations. Breaks and 'missing breaks' are intimately related to the geometry and deceleration of the jets responsible for GRBs. In the frame of the 'cannonball' (CB) model of GRBs and XRFs, we analyze the cited extreme behaviours (canonical and pure power-law) and intermediate cases spanning the observed range of X-ray AG shapes. We show that the entire panoply of X-ray light-curve shapes --measured with Swift and other satellites-- are as anticipated, on very limpid grounds, by the CB model. We test the expected correlations between the...

  19. Structural changes in Central and Eastern European economies: breaking news or breaking the ice?

    Czech Academy of Sciences Publication Activity Database

    Égert, B.; Jiménez-Rodríguez, R.; Kočenda, Evžen; Morales-Zumaquero, A.

    2006-01-01

    Roč. 39, 1-2 (2006), s. 85-103 ISSN 1573-9414 R&D Projects: GA MŠk LC542 Institutional research plan: CEZ:MSM0021620846 Keywords : Central and Eastern European (CEE) countries * multiple structural breaks * volatility Subject RIV: AH - Economics

  20. Structural changes in transition economies: breaking the news or breaking the ice?

    Czech Academy of Sciences Publication Activity Database

    Égert, B.; Jiménez-Rodríguez, R.; Kočenda, Evžen; Morales-Zumaquero, A.

    -, č. 16 (2006), s. 1-15 Institutional research plan: CEZ:AV0Z70850503 Keywords : transition countries * structural break * volatility Subject RIV: AH - Economics http://deepblue.lib.umich.edu/bitstream/2027.42/41234/1/IPC-working-paper-016-Kocenda.pdf

  1. To Break it Down or Not Break it Down: That is the Question!

    Science.gov (United States)

    Coker, Cheryl A.

    2006-01-01

    Learning a new skill, even a seemingly simple one, can be an overwhelming task for a beginner. A question often faced by the practitioner as a result is whether or not to break the skill into parts for initial practice. Skill complexity and skill organization interact to provide direction as to whether whole or part practice should be employed in…

  2. Rejoining of x-ray induced chromosome breaks in human cells and its relationship to cellular repair

    International Nuclear Information System (INIS)

    Cornforth, M.N.

    1985-01-01

    A method was developed to improve the resolution for measuring breaks produced in interphase chromosomes by X-rays following the induction of premature chromosome condensation (PCC). It is based on the principle of 5-BrdU incorporation into the DNA of HeLa mitotic cells, which act as inducers of PCC when they are fused to diploid human fibroblasts. After a modified Fluorescence Plus Giemsa (FPG) protocol, the PCC stain intensely, while the mitotic inducer chromosomes stain faintly. The dose response for density inhibited (G 0 ) human cells was linear from 10.9 to 600 rad, with a slope of 0.06 breaks per cell per rad. Upon incubation at 37 0 C, half of the breaks disappeared in 2 hours. Following a dose of 600 rad the initial rate of break rejoining mirrored the rate of increase in survival from post-irradiation incubation, due to the repair of potentially lethal damage (PLD). The X-ray induced PCC rejoining characteristics from two ataxia telangiectasia (A-T) cell lines were compared to profiles obtained with normal cells. Both normal and A-T cells apparently sustained the same initial level of radiation damage, and both cell types rejoined breaks at the same rate. However, while normal cells eventually rejoined all but about 5% of the breaks produced by 600 rad, the A-T lines were left with 5-6 times the level of residual damage. These experiments demonstrate that progression of cells into S phase is not a necessary condition for the measured frequency of chromosome fragments observed in X-irradiated A-T cells

  3. The latest from the LHC: a well-deserved break

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    A long and successful period of beam operation came to an end as scheduled on Monday 6 December . Since the first beam of 2010 was injected into the LHC on 28 February, a huge amount of progress has been made. After a technical stop of a few weeks coinciding with the end-of-year break, the LHC hardware systems will be restarted in January to be ready for the first beam of 2011 around 21 February.   The majority of the year has been dedicated to proton operation, with three distinct phases; (i) few (up to 13) low intensity bunches; (ii) a few (up to 50) high intensity bunches; (iii) many (almost 400) high intensity bunches using the bunch train scheme with 150 ns spacing. With peak luminosities of 2×1032 cm-2 s-1 and almost 50 pb-1 of integrated luminosity delivered to the experiments by late October, attention switched to operation with ions, in November After a rapid re-commissioning of the machine with ions, the physics run started on 8 November and continued for 4 weeks. The number ...

  4. [XPS analysis of beads formed by fuse breaking of electric copper wire].

    Science.gov (United States)

    Wu, Ying; Meng, Qing-Shan; Wang, Xin-Ming; Gao, Wei; Di, Man

    2010-05-01

    The in-depth composition of beads formed by fuse breaking of the electric copper wire in different circumstances was studied by XPS with Ar+ ion sputtering. In addition, the measured Auger spectra and the calculated Auger parameters were compared for differentiation of the substances of Cu and Cu2O. Corresponding to the sputtering depth, the molten product on a bead induced directly by fuse breaking of the copper wire without cover may be distinguished as three portions: surface layer with a drastic decrease in carbon content; intermediate layer with a gentle change in oxygen content and gradually diminished carbon peak, and consisting of Cu2O; transition layer without Cu2O and with a rapid decrease in oxygen content. While the molten product on a bead formed by fuse breaking of the copper wire after its insulating cover had been burned out may be distinguished as two portions: surface layer with carbon content decreasing quickly; subsurface layer without Cu2O and with carbon and oxygen content decreasing gradually. Thus, it can be seen that there was an obvious interface between the layered surface product and the substrate for the first type of bead, while as to the second type of bead there was no interface. As a result, the presence of Cu2O and the quantitative results can be used to identify the molten product on a bead induced directly by fuse breaking of the copper wire without cover and the molten product on a bead formed by fuse breaking of the cupper wire after its insulating cover had been burned out, as a complementary technique for the judgments of fire cause.

  5. Induction generator-induction motor wind-powered pumping system

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, M.S.; Lyra, R.O.C.; Silva, S.R. [CPDEE - UFMG, Belo Horizonte (Brazil)

    1997-12-31

    The energy storage matter plays an important role in wind-electric conversion systems for isolated applications. Having that in mind, two different approaches can be basically considered: either the immediate conversion of the generated electric energy, as in a water pumping system or electric energy storage for later use, as in a battery charging system. Due to some features such as no need of an external reactive power source and, sometimes, a gearbox, permanent-magnet synchronous generators have been broadly used in low rated power isolated systems. Despite that, system performance can be affected when the generator is feeding an inductive load (e.g., an induction motor) under variable-speed-variable-frequency operational conditions. Since there is no effective flux control, motor overload may occur at high wind speeds. Thus, good system performance can be obtained through additional control devices which may increase system cost. Although being rugged and cheap, induction machines always work as a reactive power drain; therefore, they demand an external reactive power source. Considering that, reactive static compensators appear as an attractive alternative to the cost x performance problem. In addition to that, different control strategies can be used so that system performance can be improved.

  6. Symmetry Breaking in MILP Formulations for Unit Commitment Problems

    KAUST Repository

    Lima, Ricardo

    2015-12-11

    This paper addresses the study of symmetry in Unit Commitment (UC) problems solved by Mixed Integer Linear Programming (MILP) formulations, and using Linear Programming based Branch & Bound MILP solvers. We propose three sets of symmetry breaking constraints for UC MILP formulations exhibiting symmetry, and its impact on three UC MILP models are studied. The case studies involve the solution of 24 instances by three widely used models in the literature, with and without symmetry breaking constraints. The results show that problems that could not be solved to optimality within hours can be solved with a relatively small computational burden if the symmetry breaking constraints are assumed. The proposed symmetry breaking constraints are also compared with the symmetry breaking methods included in two MILP solvers, and the symmetry breaking constraints derived in this work have a distinct advantage over the methods in the MILP solvers.

  7. Chiral symmetry breaking and confinement - solutions of relativistic wave equations

    International Nuclear Information System (INIS)

    Murugesan, P.

    1983-01-01

    In this thesis, an attempt is made to explore the question whether confinement automatically leads to chiral symmetry breaking. While it should be accepted that chiral symmetry breaking manifests in nature in the absence of scalar partners of pseudoscalar mesons, it does not necessarily follow that confinement should lead to chiral symmetry breaking. If chiral conserving forces give rise to observed spectrum of hadrons, then the conjuncture that confinement is responsible for chiral symmetry breaking is not valid. The method employed to answer the question whether confinement leads to chiral symmetry breaking or not is to solve relativistic wave equations by introducing chiral conserving as well as chiral breaking confining potentials and compare the results with experimental observations. It is concluded that even though chiral symmetry is broken in nature, confinement of quarks need not be the cause of it

  8. Symmetry Breaking in MILP Formulations for Unit Commitment Problems

    KAUST Repository

    Lima, Ricardo; Novais, Augusto Q.

    2015-01-01

    This paper addresses the study of symmetry in Unit Commitment (UC) problems solved by Mixed Integer Linear Programming (MILP) formulations, and using Linear Programming based Branch & Bound MILP solvers. We propose three sets of symmetry breaking constraints for UC MILP formulations exhibiting symmetry, and its impact on three UC MILP models are studied. The case studies involve the solution of 24 instances by three widely used models in the literature, with and without symmetry breaking constraints. The results show that problems that could not be solved to optimality within hours can be solved with a relatively small computational burden if the symmetry breaking constraints are assumed. The proposed symmetry breaking constraints are also compared with the symmetry breaking methods included in two MILP solvers, and the symmetry breaking constraints derived in this work have a distinct advantage over the methods in the MILP solvers.

  9. PWR cold-leg small break loca with faulty HPI

    International Nuclear Information System (INIS)

    Kumamaru, H.; Kukita, Y.

    1991-01-01

    The ROSA-IV Large Scale Test Facility (LSTF) is a 1/48 volumetrically-scaled model of a pressurized water reactor (PWR). At the LSTF are performed cold-leg small-break loss-of-coolant accident (LOCA) tests with faulty high pressure injection (HPI) system for break areas from 0.5% to 10% and an intentional primary system depressurization test following a small-break LOCA test. A simple prediction model is proposed for prediction of times of major events. Test data and calculations show that intentional primary system depressurization with use of the pressurizer power-operated relief valves (PORVs) is effective for break areas of approximately 0.5% or less, is unnecessary for breaks of 5% or more, and is insufficient for intermediate break areas to maintain adequate core cooling. (author)

  10. Yield of single-strand breaks in the DNA of E.coli 10 msec after irradiation

    International Nuclear Information System (INIS)

    Fox, R.A.; Fielden, E.M.; Sapora, O.

    1976-01-01

    The rapid mixing of 0.3M alkali with a suspension of E.coli B/r 6 +- 3 and 144 +- 3 msec after irradiation with electrons (4.3 MeV, 0 to 50 krad) has been used to make a comparison of the yields of single strand breaks in the presence and absence of oxygen. No significant difference was observed between the numbers of single strand breaks appearing at 6 and 144 msec after irradiation. Assuming that mixing with alkali inactivates the cellular repair enzymes within several milliseconds, these results indicate that enzymic repair does not operate within this time scale. It seems probable that radiation chemical processes are responsible for the initial oxygen effect on single strand breaks. (U.K.)

  11. The non-equilibrium response of a superconductor to pair-breaking radiation measured over a broad frequency band

    Energy Technology Data Exchange (ETDEWEB)

    Visser, P. J. de, E-mail: p.j.devisser@tudelft.nl [Kavli Institute of NanoScience, Faculty of Applied Sciences, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft (Netherlands); Yates, S. J. C. [SRON Netherlands Institute for Space Research, Landleven 12, 9747AD Groningen (Netherlands); Guruswamy, T.; Goldie, D. J.; Withington, S. [Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE (United Kingdom); Neto, A.; Llombart, N. [Faculty of Electrical Engineering, Mathematics and Computer Science, Terahertz Sensing Group, Delft University of Technology, Mekelweg 4, 2628 CD Delft (Netherlands); Baryshev, A. M. [SRON Netherlands Institute for Space Research, Landleven 12, 9747AD Groningen (Netherlands); Kapteyn Astronomical Institute, University of Groningen, Landleven 12, 9747 AD Groningen (Netherlands); Klapwijk, T. M. [Kavli Institute of NanoScience, Faculty of Applied Sciences, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft (Netherlands); Physics Department, Moscow State Pedagogical University, Moscow 119991 (Russian Federation); Baselmans, J. J. A. [SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht (Netherlands); Faculty of Electrical Engineering, Mathematics and Computer Science, Terahertz Sensing Group, Delft University of Technology, Mekelweg 4, 2628 CD Delft (Netherlands)

    2015-06-22

    We have measured the absorption of terahertz radiation in a BCS superconductor over a broad range of frequencies from 200 GHz to 1.1 THz, using a broadband antenna-lens system and a tantalum microwave resonator. From low frequencies, the response of the resonator rises rapidly to a maximum at the gap edge of the superconductor. From there on, the response drops to half the maximum response at twice the pair-breaking energy. At higher frequencies, the response rises again due to trapping of pair-breaking phonons in the superconductor. In practice, this is a measurement of the frequency dependence of the quasiparticle creation efficiency due to pair-breaking in a superconductor. The efficiency, calculated from the different non-equilibrium quasiparticle distribution functions at each frequency, is in agreement with the measurements.

  12. The non-equilibrium response of a superconductor to pair-breaking radiation measured over a broad frequency band

    International Nuclear Information System (INIS)

    Visser, P. J. de; Yates, S. J. C.; Guruswamy, T.; Goldie, D. J.; Withington, S.; Neto, A.; Llombart, N.; Baryshev, A. M.; Klapwijk, T. M.; Baselmans, J. J. A.

    2015-01-01

    We have measured the absorption of terahertz radiation in a BCS superconductor over a broad range of frequencies from 200 GHz to 1.1 THz, using a broadband antenna-lens system and a tantalum microwave resonator. From low frequencies, the response of the resonator rises rapidly to a maximum at the gap edge of the superconductor. From there on, the response drops to half the maximum response at twice the pair-breaking energy. At higher frequencies, the response rises again due to trapping of pair-breaking phonons in the superconductor. In practice, this is a measurement of the frequency dependence of the quasiparticle creation efficiency due to pair-breaking in a superconductor. The efficiency, calculated from the different non-equilibrium quasiparticle distribution functions at each frequency, is in agreement with the measurements

  13. Titrated Misoprostol Versus Dinoprostone for Labor Induction

    African Journals Online (AJOL)

    Aim: This study designed to compare titrated misoprostol regarding its safety and efficacy with dinoprostone for induction of labor. ... Statistical analysis done using Student's t-test for quantitative data and ..... induction: A pilot study. Rev Bras ...

  14. Scalable conditional induction variables (CIV) analysis

    KAUST Repository

    Oancea, Cosmin E.; Rauchwerger, Lawrence

    2015-01-01

    challenges to automatic parallelization. Because the complexity of such induction variables is often due to their conditional evaluation across the iteration space of loops we name them Conditional Induction Variables (CIV). This paper presents a flow

  15. Rapid Prototyping Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The ARDEC Rapid Prototyping (RP) Laboratory was established in December 1992 to provide low cost RP capabilities to the ARDEC engineering community. The Stratasys,...

  16. Analysis of native cellular DNA after heavy ion irradiation: DNA double-strand breaks in CHO-K1 cells

    International Nuclear Information System (INIS)

    Heilmann, J.; Taucher-Scholz, G.; Kraft, G.

    1994-11-01

    A fast assay for the detection of DNA double-strand breaks was developed involving constant field gel electrophoresis (Taucher-Scholz et al., 1994) and densitometric scanning of agarose gels stained with ethidium bromide. With this technique, DSB induction was investigated after irradiation of CHO cells with carbon ions with LET values between 14 keV/μm and 400 keV/μm. In parallel, a computer code was developed to simulate both the principle of the electrophoretic detection of DNA double-strand breaks and the action of radiations of different ionization density. The results of the experiments and the calculations are presented here and compared with each other. (orig./HSI)

  17. New particles and breaking the colour symmetry

    International Nuclear Information System (INIS)

    Krolikowski, W.

    1975-01-01

    In the framework of one-gluon-exchange static forces mediated by a colour octet or nonet of vector gluons, we discuss quark binding in coloured-meson states and its connection with breaking the colour symmetry. A possible identification of psi (3.1), psi(3.7) and the broad bump at 4.1 GeV with some coloured bound states of quarks and antiquarks is pointed out. This identification implies the existence of a second bump in the region of 5 GeV. The general conclusion of the paper is that the colour interpretation of the new particles may be true only if the colour symmetry is badly broken (provided the considered forces are relevant). (author)

  18. Structural breaks and energy efficiency in Fiji

    International Nuclear Information System (INIS)

    Bhaskara Rao, B.; Rao, Gyaneshwar

    2009-01-01

    This paper examines how energy-output ratios (EYRs) in Fiji have responded to the major energy crises and in particular if these ratios have declined after the energy shocks. The expectation is that energy efficiency should improve after an energy crisis. For this purpose we have used at first a few simpler procedures and then a recently developed more powerful tests for structural breaks by Bai and Perron [Bai, J., Perron, P., 1998. Estimating and testing linear models with multiple structural changes. Econometrica 66, 47-78; Bai, J., Perron, P., 2003a. Computation and analysis of multiple structural change models. Journal of Applied Econometrics 18, 1-22; Bai, J., Perron, P., 2003b. Critical values for multiple structural change tests. Econometrics Journal 6, 72-78]. Policy implications of our results are discussed.

  19. Passive appendages generate drift through symmetry breaking

    Science.gov (United States)

    Lācis, U.; Brosse, N.; Ingremeau, F.; Mazzino, A.; Lundell, F.; Kellay, H.; Bagheri, S.

    2014-10-01

    Plants and animals use plumes, barbs, tails, feathers, hairs and fins to aid locomotion. Many of these appendages are not actively controlled, instead they have to interact passively with the surrounding fluid to generate motion. Here, we use theory, experiments and numerical simulations to show that an object with a protrusion in a separated flow drifts sideways by exploiting a symmetry-breaking instability similar to the instability of an inverted pendulum. Our model explains why the straight position of an appendage in a fluid flow is unstable and how it stabilizes either to the left or right of the incoming flow direction. It is plausible that organisms with appendages in a separated flow use this newly discovered mechanism for locomotion; examples include the drift of plumed seeds without wind and the passive reorientation of motile animals.

  20. Passive appendages aid locomotion through symmetry breaking

    Science.gov (United States)

    Bagheri, Shervin; Lacis, Ugis; Mazzino, Andrea; Kellay, Hamid; Brosse, Nicolas; Lundell, Fredrik; Ingremeau, Francois

    2014-11-01

    Plants and animals use plumes, barbs, tails, feathers, hairs, fins, and other types of appendages to aid locomotion. Despite their enormous variation, passive appendages may contribute to locomotion by exploiting the same physical mechanism. We present a new mechanism that applies to body appendages surrounded by a separated flow, which often develops behind moving bodies larger than a few millimeters. We use theory, experiments, and numerical simulations to show that bodies with protrusions turn and drift by exploiting a symmetry-breaking instability similar to the instability of an inverted pendulum. Our model explains why the straight position of an appendage in flowing fluid is unstable and how it stabilizes either to the left or right of the incoming fluid flow direction. The discovery suggests a new mechanism of locomotion that may be relevant for certain organisms; for example, how plumed seeds may drift without wind and how motile animals may passively reorient themselves.