Chronic exposure of imidacloprid and clothianidin reduce queen survival, foraging, and nectar storing in colonies of Bombus impatiens.

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Jamison Scholer

Full Text Available In an 11-week greenhouse study, caged queenright colonies of Bombus impatiens Cresson, were fed treatments of 0 (0 ppb actual residue I, imidacloprid; C, clothianidin, 10 (14 I, 9 C, 20 (16 I, 17C, 50 (71 I, 39 C and 100 (127 I, 76 C ppb imidacloprid or clothianidin in sugar syrup (50%. These treatments overlapped the residue levels found in pollen and nectar of many crops and landscape plants, which have higher residue levels than seed-treated crops (less than 10 ppb, corn, canola and sunflower. At 6 weeks, queen mortality was significantly higher in 50 ppb and 100 ppb and by 11 weeks in 20 ppb-100 ppb neonicotinyl-treated colonies. The largest impact for both neonicotinyls starting at 20 (16 I, 17 C ppb was the statistically significant reduction in queen survival (37% I, 56% C ppb, worker movement, colony consumption, and colony weight compared to 0 ppb treatments. Bees at feeders flew back to the nest box so it appears that only a few workers were collecting syrup in the flight box and returning the syrup to the nest. The majority of the workers sat immobilized for weeks on the floor of the flight box without moving to fed at sugar syrup feeders. Neonicotinyl residues were lower in wax pots in the nest than in the sugar syrup that was provided. At 10 (14 ppb I and 50 (39 ppb C, fewer males were produced by the workers, but queens continued to invest in queen production which was similar among treatments. Feeding on imidacloprid and clothianidin can cause changes in behavior (reduced worker movement, consumption, wax pot production, and nectar storage that result in detrimental effects on colonies (queen survival and colony weight. Wild bumblebees depending on foraging workers can be negatively impacted by chronic neonicotinyl exposure at 20 ppb.

Chronic exposure of imidacloprid and clothianidin reduce queen survival, foraging, and nectar storing in colonies of Bombus impatiens.

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Scholer, Jamison; Krischik, Vera

2014-01-01

In an 11-week greenhouse study, caged queenright colonies of Bombus impatiens Cresson, were fed treatments of 0 (0 ppb actual residue I, imidacloprid; C, clothianidin), 10 (14 I, 9 C), 20 (16 I, 17C), 50 (71 I, 39 C) and 100 (127 I, 76 C) ppb imidacloprid or clothianidin in sugar syrup (50%). These treatments overlapped the residue levels found in pollen and nectar of many crops and landscape plants, which have higher residue levels than seed-treated crops (less than 10 ppb, corn, canola and sunflower). At 6 weeks, queen mortality was significantly higher in 50 ppb and 100 ppb and by 11 weeks in 20 ppb-100 ppb neonicotinyl-treated colonies. The largest impact for both neonicotinyls starting at 20 (16 I, 17 C) ppb was the statistically significant reduction in queen survival (37% I, 56% C) ppb, worker movement, colony consumption, and colony weight compared to 0 ppb treatments. Bees at feeders flew back to the nest box so it appears that only a few workers were collecting syrup in the flight box and returning the syrup to the nest. The majority of the workers sat immobilized for weeks on the floor of the flight box without moving to fed at sugar syrup feeders. Neonicotinyl residues were lower in wax pots in the nest than in the sugar syrup that was provided. At 10 (14) ppb I and 50 (39) ppb C, fewer males were produced by the workers, but queens continued to invest in queen production which was similar among treatments. Feeding on imidacloprid and clothianidin can cause changes in behavior (reduced worker movement, consumption, wax pot production, and nectar storage) that result in detrimental effects on colonies (queen survival and colony weight). Wild bumblebees depending on foraging workers can be negatively impacted by chronic neonicotinyl exposure at 20 ppb.

[Neoplastic transformation of mouse fibroblasts under the influence of high-energy protons and gamma-rays].

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Voskanian, K Sh

2004-01-01

Oncoginic transformations of mouse fibroblasts C3H10T1/2 after exposure to proton energies 150 and 584 MeV were compared with fibroblast effects of gamma-radiation. Prior to exposure, cell populations (2.7 x 10(3) cells/cm2) were inoculated in plastic vials with the surface area of 75 cm2 and cultivated 11 days. Survivability was determined by comparing the number of cell colonies in irradiated and non-irradiated (control) vials. Transformation rate was calculated by dividing the total transformation focus number by the number of survived cells in a vial. Rate of oncogenic transformations after gamma- and proton (584 MeV) irradiation was essentially identical, i.e. the parameter grew rapidly at the doses 1 Gy. In the dose interval between 1 and 5 Gy, transformation rate for proton energy 150 MeV was found low compared with gamma-radiation and proton energy 584 MeV. It is hypothesized that the different transformation rate after exposure to proton energy 150 MeV is linked with the high linear energy transfer as compared with the proton energy of 584 MeV and gamma-radiation.

Biological intercomparison using gut crypt survivals for proton and carbon-ion beams

International Nuclear Information System (INIS)

Uzawa, Akiko; Ando, Koichi; Furusawa, Yoshiya

2007-01-01

Charged particle therapy depends on biological information for the dose prescription. Relative biological effectiveness or RBE for this requirement could basically be provided by experimental data. As RBE values of protons and carbon ions depend on several factors such as cell/tissue type, biological endpoint, dose and fractionation schedule, a single RBE value could not deal with all different radiosensitivities. However, any biological model with accurate reproducibility is useful for comparing biological effectiveness between different facilities. We used mouse gut crypt survivals as endpoint, and compared the cell killing efficiency of proton beams at three Japanese facilities. Three Linac X-ray machines with 4 and 6 MeV were used as reference beams, and there was only a small variation (coefficient of variance<2%) in biological effectiveness among them. The RBE values of protons relative to Linac X-rays ranged from 1.0 to 1.11 at the middle of a 6-cm SOBP (spread-out Bragg peak) and from 0.96 to 1.01 at the entrance plateau. The coefficient of variance for protons ranged between 4.0 and 5.1%. The biological comparison of carbon ions showed fairly good agreement in that the difference in biological effectiveness between National Institute of Radiological Sciences (NIRS)/ Heavy Ion Medical Accelerator in Chiba (HIMAC) and Gesellschaft fur Schwerionenforschung (GSI)/Heavy Ion Synchrotron (SIS) was 1% for three positions within the 6-cm SOBP. The coefficient of variance was <1.7, <0.6 and <1.6% for proximal, middle and distal SOBP, respectively. We conclude that the inter-institutional variation of biological effectiveness is smaller for carbon ions than protons, and that beam-spreading methods of carbon ions do not critically influence gut crypt survival. (author)

Temporal dynamics of European bat Lyssavirus type 1 and survival of Myotis myotis bats in natural colonies.

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Amengual, Blanca; Bourhy, Hervé; López-Roig, Marc; Serra-Cobo, Jordi

2007-06-27

Many emerging RNA viruses of public health concern have recently been detected in bats. However, the dynamics of these viruses in natural bat colonies is presently unknown. Consequently, prediction of the spread of these viruses and the establishment of appropriate control measures are hindered by a lack of information. To this aim, we collected epidemiological, virological and ecological data during a twelve-year longitudinal study in two colonies of insectivorous bats (Myotis myotis) located in Spain and infected by the most common bat lyssavirus found in Europe, the European bat lyssavirus subtype 1 (EBLV-1). This active survey demonstrates that cyclic lyssavirus infections occurred with periodic oscillations in the number of susceptible, immune and infected bats. Persistence of immunity for more than one year was detected in some individuals. These data were further used to feed models to analyze the temporal dynamics of EBLV-1 and the survival rate of bats. According to these models, the infection is characterized by a predicted low basic reproductive rate (R(0) = 1.706) and a short infectious period (D = 5.1 days). In contrast to observations in most non-flying animals infected with rabies, the survival model shows no variation in mortality after EBLV-1 infection of M. myotis. These findings have considerable public health implications in terms of management of colonies where lyssavirus-positive bats have been recorded and confirm the potential risk of rabies transmission to humans. A greater understanding of the dynamics of lyssavirus in bat colonies also provides a model to study how bats contribute to the maintenance and transmission of other viruses of public health concern.

Temporal dynamics of European bat Lyssavirus type 1 and survival of Myotis myotis bats in natural colonies.

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Blanca Amengual

Full Text Available Many emerging RNA viruses of public health concern have recently been detected in bats. However, the dynamics of these viruses in natural bat colonies is presently unknown. Consequently, prediction of the spread of these viruses and the establishment of appropriate control measures are hindered by a lack of information. To this aim, we collected epidemiological, virological and ecological data during a twelve-year longitudinal study in two colonies of insectivorous bats (Myotis myotis located in Spain and infected by the most common bat lyssavirus found in Europe, the European bat lyssavirus subtype 1 (EBLV-1. This active survey demonstrates that cyclic lyssavirus infections occurred with periodic oscillations in the number of susceptible, immune and infected bats. Persistence of immunity for more than one year was detected in some individuals. These data were further used to feed models to analyze the temporal dynamics of EBLV-1 and the survival rate of bats. According to these models, the infection is characterized by a predicted low basic reproductive rate (R(0 = 1.706 and a short infectious period (D = 5.1 days. In contrast to observations in most non-flying animals infected with rabies, the survival model shows no variation in mortality after EBLV-1 infection of M. myotis. These findings have considerable public health implications in terms of management of colonies where lyssavirus-positive bats have been recorded and confirm the potential risk of rabies transmission to humans. A greater understanding of the dynamics of lyssavirus in bat colonies also provides a model to study how bats contribute to the maintenance and transmission of other viruses of public health concern.

The Small Colony Variant of Listeria monocytogenes Is More Tolerant to Antibiotics and Has Altered Survival in RAW 264.7 Murine Macrophages

DEFF Research Database (Denmark)

Curtis, Thomas; Gram, Lone; Knudsen, Gitte Maegaard

2016-01-01

Small Colony Variant (SCV) cells of bacteria are a slow-growing phenotype that result from specific defects in the electron transport chain. They form pinpoint colonies on agar plates and have a variety of phenotypic characteristics, such as altered carbon metabolism, decreased toxin and lytic...... monocytogenes (strain SCV E18), similar to the high persister mutant phenotype, survived significantly better than the wild type when exposed over a 48-h period to concentrations above Minimal Inhibitory Concentration for most tested antibiotics. SCV E18 survived more poorly than the wildtype in unactivated RAW......264.7 macrophage cells, presumably because of its reduced listeriolysin O expression, however, it survived better in reactive oxygen species producing, phorbol 12-myristate 13-acetate-activated macrophages. Although SCV E18 was sensitive to oxygen as it entered the stationary phase...

Area-based cell colony surviving fraction evaluation: A novel fully automatic approach using general-purpose acquisition hardware.

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Militello, Carmelo; Rundo, Leonardo; Conti, Vincenzo; Minafra, Luigi; Cammarata, Francesco Paolo; Mauri, Giancarlo; Gilardi, Maria Carla; Porcino, Nunziatina

2017-10-01

The current methodology for the Surviving Fraction (SF) measurement in clonogenic assay, which is a technique to study the anti-proliferative effect of treatments on cell cultures, involves manual counting of cell colony forming units. This procedure is operator-dependent and error-prone. Moreover, the identification of the exact colony number is often not feasible due to the high growth rate leading to the adjacent colony merging. As a matter of fact, conventional assessment does not deal with the colony size, which is generally correlated with the delivered radiation dose or the administered cytotoxic agent. Considering that the Area Covered by Colony (ACC) is proportional to the colony number and size as well as to the growth rate, we propose a novel fully automatic approach exploiting Circle Hough Transform, to automatically detect the wells in the plate, and local adaptive thresholding, which calculates the percentage of ACC for the SF quantification. This measurement relies just on this covering percentage and does not consider the colony number, preventing inconsistencies due to intra- and inter-operator variability. To evaluate the accuracy of the proposed approach, we compared the SFs obtained by our automatic ACC-based method against the conventional counting procedure. The achieved results (r = 0.9791 and r = 0.9682 on MCF7 and MCF10A cells, respectively) showed values highly correlated with the measurements using the traditional approach based on colony number alone. The proposed computer-assisted methodology could be integrated in laboratory practice as an expert system for the SF evaluation in clonogenic assays. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of x-ray and neutron irradiation on spherical colonies

International Nuclear Information System (INIS)

Aramaki, Ryoji

1980-01-01

Responses of in vitro cultured mammalian cells in spherical colonies to 200 kVp x-rays and D-T neutrons were studied using reproductive capacity as a criterion for survival. Cell lines used were FM3A, L5 and Chinese hamster V79. The spherical colonies exposed to x-rays exhibited two-component survival curves. All cells used were more radio-resistant in spherical colonies than in single cell suspensions. It was suggested that this difference in response was attributable to the presence of hypoxic cells in spherical colonies. Dose-modifying Factor (DMF), the ratios of D 0 of the second slopes of the curves for spherical colonies to those for single cells, were 1.6 for FM3A, 1.8 for L5, and 1.7 for Chinese hamster V79. The hypoxic cell fractions in spherical colonies for FM3A, L5, and Chinese hamster V79, were 0.1, 0.6 and 0.4, respectively, resulting in variations in cell survival in spherical colonies following x-radiation. No significant difference was observed between responses of spherical colonies and single cell suspensions to D-T neutrons. FM3A and Chinese hamster V79 showed two-component survival curves when irradiated with neutrons at 37 0 C, but not at 25 0 C. The repair of potentially lethal and sub-lethal damage was also investigated using FM3A in spherical colonies. No detectable repair of potentially lethal damage was observed for x-rays and D-T neutrons. The effect of neutron fractionation was considerably smaller for spherical colonies as compared to single cells. (author)

Assessment of Chronic Sublethal Effects of Imidacloprid on Honey Bee Colony Health

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Dively, Galen P.; Embrey, Michael S.; Kamel, Alaa; Hawthorne, David J.; Pettis, Jeffery S.

2015-01-01

Here we present results of a three-year study to determine the fate of imidacloprid residues in hive matrices and to assess chronic sublethal effects on whole honey bee colonies fed supplemental pollen diet containing imidacloprid at 5, 20 and 100 μg/kg over multiple brood cycles. Various endpoints of colony performance and foraging behavior were measured during and after exposure, including winter survival. Imidacloprid residues became diluted or non-detectable within colonies due to the processing of beebread and honey and the rapid metabolism of the chemical. Imidacloprid exposure doses up to 100 μg/kg had no significant effects on foraging activity or other colony performance indicators during and shortly after exposure. Diseases and pest species did not affect colony health but infestations of Varroa mites were significantly higher in exposed colonies. Honey stores indicated that exposed colonies may have avoided the contaminated food. Imidacloprid dose effects was delayed later in the summer, when colonies exposed to 20 and 100 μg/kg experienced higher rates of queen failure and broodless periods, which led to weaker colonies going into the winter. Pooled over two years, winter survival of colonies averaged 85.7, 72.4, 61.2 and 59.2% in the control, 5, 20 and 100 μg/kg treatment groups, respectively. Analysis of colony survival data showed a significant dose effect, and all contrast tests comparing survival between control and treatment groups were significant, except for colonies exposed to 5 μg/kg. Given the weight of evidence, chronic exposure to imidacloprid at the higher range of field doses (20 to 100 μg/kg) in pollen of certain treated crops could cause negative impacts on honey bee colony health and reduced overwintering success, but the most likely encountered high range of field doses relevant for seed-treated crops (5 μg/kg) had negligible effects on colony health and are unlikely a sole cause of colony declines. PMID:25786127

Development rate and brood production in haplo- and pleometrotic colonies of Oecophylla smaragdina

DEFF Research Database (Denmark)

Offenberg, Joachim; Peng, Renkang; Nielsen, Mogens Gissel

2012-01-01

Pleometrosis (colony founding by multiple queens) may improve life history characteristics that are important for early colony survival. When queens unite their initial brood, the number of workers present when incipient colonies open may be higher than for single queen colonies. Further, the time...... until the first worker emerges may shorten. For territorial species and species that rob brood from neighbouring colonies, a faster production of more workers may improve the chance of surviving intraspecific competition. In this study, the time from the nuptial flight to the emergence of the first...

Predicting bat colony survival under controls targeting multiple transmission routes of white-nose syndrome.

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Meyer, A D; Stevens, D F; Blackwood, J C

2016-11-21

White-nose syndrome (WNS) is a lethal infection of bats caused by the psychrophilic fungus Pseudogymnoascus destructans (Pd). Since the first cases of WNS were documented in 2006, it is estimated that as many as 5.5million bats have succumbed in the United States-one of the fastest mammalian die-offs due to disease ever observed, and the first known sustained epizootic of bats. WNS is contagious between bats, and mounting evidence suggests that a persistent environmental reservoir of Pd plays a significant role in transmission as well. It is unclear, however, the relative contributions of bat-to-bat and environment-to-bat transmission to disease propagation within a colony. We analyze a mathematical model to investigate the consequences of both avenues of transmission on colony survival in addition to the efficacy of disease control strategies. Our model shows that selection of the most effective control strategies is highly dependent on the primary route of WNS transmission. Under all scenarios, however, generalized culling is ineffective and while targeted culling of infected bats may be effective under idealized conditions, it primarily has negative consequences. Thus, understanding the significance of environment-to-bat transmission is paramount to designing effective management plans. Copyright © 2016 Elsevier Ltd. All rights reserved.

Ecophysiology of gelatinous Nostoc colonies: unprecedented slow growth and survival in resource-poor and harsh environments.

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Sand-Jensen, Kaj

2014-07-01

structural substances in large Nostoc colonies cause lower quantum efficiency and assimilation number and higher light compensation points than in unicells and other aquatic macrophytes. Extremely low growth and mortality rates of N. zetterstedtii reflect stress-selected adaptation to nutrient- and DIC-poor temperate lakes, while N. pruniforme exhibits a mixed ruderal- and stress-selected strategy with slow growth and year-long survival prevailing in sub-Arctic lakes and faster growth and shorter longevity in temperate lakes. Nostoc commune and its close relative N. flagelliforme have a mixed stress-disturbance strategy not found among higher plants, with stress selection to limiting water and nutrients and disturbance selection in quiescent dry or frozen stages. Despite profound ecological differences between species, active growth of temperate specimens is mostly restricted to the same temperature range (0-35 °C; maximum at 25 °C). Future studies should aim to unravel the processes behind the extreme persistence and low metabolism of Nostoc species under ambient resource supply on sediment and soil surfaces. © The Author 2014. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Black fungal colonies as units of survival: hyphal mycosporines synthesized by rock-dwelling microcolonial fungi

International Nuclear Information System (INIS)

Gorbushina, A.A.; Whitehead, K.; Dornieden, T.; Niesse, A.; Schulte, A.; Hedges, J.I.

2003-01-01

Microcolonial fungi, long-living modified mycelia frequently occurring on desert and pseudodesert rock surfaces, are exposed to strong ultraviolet (UV) radiation, desiccation, and nutrient scarcity. They lack ascospores; all their cells grow by mitotic cell divisions and possess a thick melanized cell wall. Colonies of several randomly selected microcolonial strains were cultured and their structure was examined by cryo-scanning and transmission electron microscopy. Extracts of nine strains were analyzed by high performance liquid chromatography interfaced with mass spectrometry for the presence of mycosporines. These UV-absorbing compounds, common in spores and other survival structures, were thought to be limited to reproductive morphogenesis and unknown in growing hyphae. Mycosporines were present in eight of the strains, and mycosporine-glutaminol-glucoside (λmax = 310 nm; MH+ = 465) was the major mycosporine detected. Mycosporines present in the vegetative fungal microcolonies may be associated with the high survival potential, nonexpansive intracolonial growth; and longevity of these fungi. Intrahyphal growth and recolonization of old cells by new ones were observed in all strains investigated. (author)

Black fungal colonies as units of survival: hyphal mycosporines synthesized by rock-dwelling microcolonial fungi

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Gorbushina, A.A. [Geomicrobiology, Inst. for Chemistry and Biology of the Marine Environment, Oldenburg (Germany); Whitehead, K. [Univ. of Washington, School of Oceanography, Seattle, Washington (United States); Dornieden, T.; Niesse, A.; Schulte, A. [Geomicrobiology, Inst. for Chemistry and Biology of the Marine Environment, Oldenburg (Germany); Hedges, J.I. [Univ. of Washington, School of Oceanography, Seattle, Washington (United States)

2003-02-01

Microcolonial fungi, long-living modified mycelia frequently occurring on desert and pseudodesert rock surfaces, are exposed to strong ultraviolet (UV) radiation, desiccation, and nutrient scarcity. They lack ascospores; all their cells grow by mitotic cell divisions and possess a thick melanized cell wall. Colonies of several randomly selected microcolonial strains were cultured and their structure was examined by cryo-scanning and transmission electron microscopy. Extracts of nine strains were analyzed by high performance liquid chromatography interfaced with mass spectrometry for the presence of mycosporines. These UV-absorbing compounds, common in spores and other survival structures, were thought to be limited to reproductive morphogenesis and unknown in growing hyphae. Mycosporines were present in eight of the strains, and mycosporine-glutaminol-glucoside ({lambda}max = 310 nm; MH+ = 465) was the major mycosporine detected. Mycosporines present in the vegetative fungal microcolonies may be associated with the high survival potential, nonexpansive intracolonial growth; and longevity of these fungi. Intrahyphal growth and recolonization of old cells by new ones were observed in all strains investigated. (author)

Dynamics of the Presence of Israeli Acute Paralysis Virus in Honey Bee Colonies with Colony Collapse Disorder

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Chunsheng Hou

2014-05-01

Full Text Available The determinants of Colony Collapse Disorder (CCD, a particular case of collapse of honey bee colonies, are still unresolved. Viruses including the Israeli acute paralysis virus (IAPV were associated with CCD. We found an apiary with colonies showing typical CCD characteristics that bore high loads of IAPV, recovered some colonies from collapse and tested the hypothesis if IAPV was actively replicating in them and infectious to healthy bees. We found that IAPV was the dominant pathogen and it replicated actively in the colonies: viral titers decreased from April to September and increased from September to December. IAPV extracted from infected bees was highly infectious to healthy pupae: they showed several-fold amplification of the viral genome and synthesis of the virion protein VP3. The health of recovered colonies was seriously compromised. Interestingly, a rise of IAPV genomic copies in two colonies coincided with their subsequent collapse. Our results do not imply IAPV as the cause of CCD but indicate that once acquired and induced to replication it acts as an infectious factor that affects the health of the colonies and may determine their survival. This is the first follow up outside the US of CCD-colonies bearing IAPV under natural conditions.

Long-term population dynamics of a managed burrowing owl colony

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Barclay, John H.; Korfanta, Nicole M.; Kauffman, Matthew J.

2011-01-01

We analyzed the population dynamics of a burrowing owl (Athene cunicularia) colony at Mineta San Jose International Airport in San Jose, California, USA from 1990-2007. This colony was managed by using artificial burrows to reduce the occurrence of nesting owls along runways and within major airport improvement projects during the study period. We estimated annual reproduction in natural and artificial burrows and age-specific survival rates with mark-recapture techniques, and we estimated the relative contribution of these vital rates to population dynamics using a life table response experiment. The breeding colony showed 2 distinct periods of change: high population growth from 7 nesting pairs in 1991 to 40 pairs in 2002 and population decline to 17 pairs in 2007. Reproduction was highly variable: annual nesting success (pairs that raised =1 young) averaged 79% and ranged from 36% to 100%, whereas fecundity averaged 3.36 juveniles/pair and ranged from 1.43 juveniles/pair to 4.54 juveniles/pair. We estimated annual adult survival at 0.710 during the period of colony increase from 1996 to 2001 and 0.465 during decline from 2002 to 2007, but there was no change in annual survival of juveniles between the 2 time periods. Long-term population growth rate (lambda) estimated from average vital rates was lambdaa=1.072 with lambdai=1.288 during colony increase and lambdad=0.921 (DELTA lambda=0.368) during decline. A life table response experiment showed that change in adult survival rate during increasing and declining phases explained more than twice the variation in growth rate than other vital rates. Our findings suggest that management and conservation of declining burrowing owl populations should address factors that influence adult survival.

Stimulated human fibroblast cell survival

International Nuclear Information System (INIS)

Smith, B.P.; Gale, K.L.; Einspenner, M.; Greenstock, C.L.; Gentner, N.E.

1992-01-01

Techniques for cloning cultured mammalian cells have supported the most universally-accepted method for measuring the induction of lethality by geno-toxicants such as ionizing radiation: the 'survival of colony-forming ability (CFA)' assay. Since most cultured human cell lines exhibit plating efficiency (i.e. the percentage of cells that are capable of reproductively surviving and dividing to form visible colonies) well below 100%, such assays are in essence 'survival of plating efficiency' assays, since they are referred to the plating (or cloning) efficiency of control (i.e. unirradiated) cells. (author). 8 refs., 2 figs

Norwegian honey bees surviving Varroa destructor mite infestations by means of natural selection.

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Oddie, Melissa A Y; Dahle, Bjørn; Neumann, Peter

2017-01-01

Managed, feral and wild populations of European honey bee subspecies, Apis mellifera , are currently facing severe colony losses globally. There is consensus that the ectoparasitic mite Varroa destructor , that switched hosts from the Eastern honey bee Apis cerana to the Western honey bee A. mellifera , is a key factor driving these losses. For >20 years, breeding efforts have not produced European honey bee colonies that can survive infestations without the need for mite control. However, at least three populations of European honey bees have developed this ability by means of natural selection and have been surviving for >10 years without mite treatments. Reduced mite reproductive success has been suggested as a key factor explaining this natural survival. Here, we report a managed A. mellifera population in Norway, that has been naturally surviving consistent V. destructor infestations for >17 years. Surviving colonies and local susceptible controls were evaluated for mite infestation levels, mite reproductive success and two potential mechanisms explaining colony survival: grooming of adult worker bees and Varroa Sensitive Hygiene (VSH): adult workers specifically detecting and removing mite-infested brood. Mite infestation levels were significantly lower in surviving colonies and mite reproductive success was reduced by 30% when compared to the controls. No significant differences were found between surviving and control colonies for either grooming or VSH. Our data confirm that reduced mite reproductive success seems to be a key factor for natural survival of infested A. mellifera colonies. However, neither grooming nor VSH seem to explain colony survival. Instead, other behaviors of the adult bees seem to be sufficient to hinder mite reproductive success, because brood for this experiment was taken from susceptible donor colonies only. To mitigate the global impact of V. destructor , we suggest learning more from nature, i.e., identifying the obviously

Norwegian honey bees surviving Varroa destructor mite infestations by means of natural selection

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Melissa A.Y. Oddie

2017-10-01

Full Text Available Background Managed, feral and wild populations of European honey bee subspecies, Apis mellifera, are currently facing severe colony losses globally. There is consensus that the ectoparasitic mite Varroa destructor, that switched hosts from the Eastern honey bee Apis cerana to the Western honey bee A. mellifera, is a key factor driving these losses. For >20 years, breeding efforts have not produced European honey bee colonies that can survive infestations without the need for mite control. However, at least three populations of European honey bees have developed this ability by means of natural selection and have been surviving for >10 years without mite treatments. Reduced mite reproductive success has been suggested as a key factor explaining this natural survival. Here, we report a managed A. mellifera population in Norway, that has been naturally surviving consistent V. destructor infestations for >17 years. Methods Surviving colonies and local susceptible controls were evaluated for mite infestation levels, mite reproductive success and two potential mechanisms explaining colony survival: grooming of adult worker bees and Varroa Sensitive Hygiene (VSH: adult workers specifically detecting and removing mite-infested brood. Results Mite infestation levels were significantly lower in surviving colonies and mite reproductive success was reduced by 30% when compared to the controls. No significant differences were found between surviving and control colonies for either grooming or VSH. Discussion Our data confirm that reduced mite reproductive success seems to be a key factor for natural survival of infested A. mellifera colonies. However, neither grooming nor VSH seem to explain colony survival. Instead, other behaviors of the adult bees seem to be sufficient to hinder mite reproductive success, because brood for this experiment was taken from susceptible donor colonies only. To mitigate the global impact of V. destructor, we suggest learning

Highly Expressed Granulocyte Colony-Stimulating Factor (G-CSF) and Granulocyte Colony-Stimulating Factor Receptor (G-CSFR) in Human Gastric Cancer Leads to Poor Survival.

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Fan, Zhisong; Li, Yong; Zhao, Qun; Fan, Liqiao; Tan, Bibo; Zuo, Jing; Hua, Kelei; Ji, Qiang

2018-03-23

BACKGROUND Chemotherapy for advanced gastric cancer (GC) patients has been the mainstay of therapy for many years. Although adding anti-angiogenic drugs to chemotherapy improves patient survival slightly, identifying anti-angiogenic therapy-sensitive patients remains challenging for oncologists. Granulocyte colony-stimulating factor (G-CSF) promotes tumor growth and angiogenesis, which can be minimized with the anti-G-CSF antibody. Thus, G-CSF might be a potential tumor marker. However, the effects of G-CSF and G-CSFR expression on GC patient survival remain unclear. MATERIAL AND METHODS Seventy GC tissue samples were collected for G-CSF and G-CSFR detection by immunohistochemistry. A total of 40 paired GC tissues and matched adjacent mucosa were used to measure the G-CSF and G-CSFR levels by ELISA. Correlations between G-CSF/G-CSFR and clinical characteristics, VEGF-A levels and overall survival were analyzed. Biological function and underlying mechanistic investigations were carried out using SGC7901 cell lines, and the effects of G-CSF on tumor proliferation, migration, and tube formation were examined. RESULTS The levels of G-CSFR were upregulated in GC tissues compared to normal mucosa tissues. Higher G-CSF expression was associated with later tumor stages and higher tumor VEGF-A and serum CA724 levels, whereas higher G-CSFR expression was associated with lymph node metastasis. Patients with higher G-CSF expression had shorter overall survival times. In vitro, G-CSF stimulated SGC7901 proliferation and migration through the JAK2/STAT3 pathway and accelerated HUVEC tube formation. CONCLUSIONS These data suggest that increased G-CSF and G-CSFR in tumors leads to unfavorable outcomes for GC patients by stimulating tumor proliferation, migration, and angiogenesis, indicating that these factors are potential tumor targets for cancer treatment.

Clinical Outcomes Among Children With Standard-Risk Medulloblastoma Treated With Proton and Photon Radiation Therapy: A Comparison of Disease Control and Overall Survival.

Science.gov (United States)

Eaton, Bree R; Esiashvili, Natia; Kim, Sungjin; Weyman, Elizabeth A; Thornton, Lauren T; Mazewski, Claire; MacDonald, Tobey; Ebb, David; MacDonald, Shannon M; Tarbell, Nancy J; Yock, Torunn I

2016-01-01

The purpose of this study was to compare long-term disease control and overall survival between children treated with proton and photon radiation therapy (RT) for standard-risk medulloblastoma. This multi-institution cohort study includes 88 children treated with chemotherapy and proton (n=45) or photon (n=43) RT between 2000 and 2009. Overall survival (OS), recurrence-free survival (RFS), and patterns of failure were compared between the 2 cohorts. Median (range) age was 6 years old at diagnosis (3-21 years) for proton patients versus 8 years (3-19 years) for photon patients (P=.011). Cohorts were similar with respect to sex, histology, extent of surgical resection, craniospinal irradiation (CSI) RT dose, total RT dose, whether the RT boost was delivered to the posterior fossa (PF) or tumor bed (TB), time from surgery to RT start, or total duration of RT. RT consisted of a median (range) CSI dose of 23.4 Gy (18-27 Gy) and a boost of 30.6 Gy (27-37.8 Gy). Median follow-up time is 6.2 years (95% confidence interval [CI]: 5.1-6.6 years) for proton patients versus 7.0 years (95% CI: 5.8-8.9 years) for photon patients. There was no significant difference in RFS or OS between patients treated with proton versus photon RT; 6-year RFS was 78.8% versus 76.5% (P=.948) and 6-year OS was 82.0% versus 87.6%, respectively (P=.285). On multivariate analysis, there was a trend for longer RFS with females (P=.058) and higher CSI dose (P=.096) and for longer OS with females (P=.093). Patterns of failure were similar between the 2 cohorts (P=.908). Disease control with proton and photon radiation therapy appears equivalent for standard risk medulloblastoma. Copyright © 2016 Elsevier Inc. All rights reserved.

The sea, the ship, the batle: survival of forms in 'Antologia da memória poética da Guerra Colonial'

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Lisa Carvalho Vasconcellos

2018-06-01

Full Text Available The book Antologia da memória poética da guerra colonial was published in 2011 by Roberto Vecchi and Margarida Calafate Ribeiro. As a poetry anthology, its purpose was to collect and give meaning to the poetical ma­terial that was created and inspired by the wars that have taken place in 1962-74 between Portugal and it´s old colonies. Among the many themes and problems proposed by the poems compiled in the volume, the review and the reclaim of the ancient Portuguese literary tradition is the one that interest us. In Antologia da memória poética da guerra colonial, the old lite­rary forms – the Galician-Portuguese love lyric, the navigation chronicles, The Lusiads’, the historical figures and heroic myths – are revisited in a creative and imaginative way. Our hypothesis is that the presence of archaic and traditional elements in the Antologia indicates a form of survival (Na­chleben of past forms and tensions (cf. Aby Warburg, they are the traces of a literary tradition that renews itself from the same points (the sea, the conquer, the lost and the destruction.

Laser-driven proton beams applied to radiobiological experiments

International Nuclear Information System (INIS)

Yogo, Akifumi

2012-01-01

The proton accelerators based on the high intensity laser system generate shorter and higher pulse beams compared to the conventional particle accelerators used for the cancer therapy. To demonstrate the radiobiological effects of the new proton beams, the program to develop a biological irradiation instrument for the DNA double-strand break was started in the fiscal year 2008. A prototype instrument was made by making use of the J-KAREN (JAEA Kansai Advanced Relativistic Engineering) laser beam. Polyimide thin film targets were used to irradiate A-549 cells. The DNA double-strand break was tested by the fluorescence spectrometry. In the second year the quantitative yield of the DNA double-strand break and its proton dose dependence were measured. The results indicated that they were comparative to the cases of the conventional particle accelerators. In the fiscal year of 2010 the design of the magnetic field for the energy selection has been changed. The new irradiation instrument, the main part of which is only about 40 cm in length as illustrated in the figure, has been constructed and tested. The experiment has been carried out using the human cancer cells (HSG) and the relative biological effectiveness (RBE) has been quantitatively evaluated by the colony assay for varied distribution of the proton beam energy. The survival fractions plotted against the dose were in good agreement with the case of 3 He beam. RBE was found not to be changed up to 1x10 7 Gy/s. Stability of the energy peak, half width and the proton density has been confirmed for this very compact instrument. (S. Funahashi)

Yeast Colonies: A Model for Studies of Aging, Environmental Adaptation, and Longevity

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Libuše Váchová

2012-01-01

Full Text Available When growing on solid surfaces, yeast, like other microorganisms, develops organized multicellular populations (colonies and biofilms that are composed of differentiated cells with specialized functions. Life within these populations is a prevalent form of microbial existence in natural settings that provides the cells with capabilities to effectively defend against environmental attacks as well as efficiently adapt and survive long periods of starvation and other stresses. Under such circumstances, the fate of an individual yeast cell is subordinated to the profit of the whole population. In the past decade, yeast colonies, with their complicated structure and high complexity that are also developed under laboratory conditions, have become an excellent model for studies of various basic cellular processes such as cell interaction, signaling, and differentiation. In this paper, we summarize current knowledge on the processes related to chronological aging, adaptation, and longevity of a colony cell population and of its differentiated cell constituents. These processes contribute to the colony ability to survive long periods of starvation and mostly differ from the survival strategies of individual yeast cells.

Relationship between lung colony and in situ assays

International Nuclear Information System (INIS)

Ando, K.; Koike, S.

1985-01-01

The relationship between different assays: tumor control, tumor growth delay and lung colony formation was examined after fast neutron and γ ray irradiations. Fibrosarcomas (NFSa) in syngeneic C3Hf mice were irradiated locally with 60 Co γ rays, fast neutrons or mixed beams (γ rays and fast neutrons). A comparison between the lung colony assay and the TRT 50 (50% tumor growth delay time) assay when cells were exposed to single doses of fast neutrons or γ rays, resulted in identical growth delay times. The fraction of cells surviving a single dose of fast neutrons, was 10 times higher than the surviving fraction of cells after a single dose of γ rays. Both doses resulted in the same tumor control probability (TCD 50 assay). Neither repair of potentially lethal damage nor tumor bed effect was sufficient to explain the difference between cell survival and tumor control probability. The surviving fraction of cells following fractionated irradiations of γ rays and fast neutrons were identical at 50% tumor control probabilities

Relationship of colony-stimulating activity to apparent kill of human colony-forming cells by irradiation and hydroxyurea

International Nuclear Information System (INIS)

Broxmeyer, H.E.; Galbraith, P.R.; Baker, F.L.

1976-01-01

Suspensions of human bone marrow cells were subjected to 137 Cs irradiation in vitro and then cultured in semisolid agar medium. Cultures of irradiated cells were stimulated with colony-stimulating activity (CSA) of different potencies, and it was found that the amount of stimulation applied to cultures influenced the apparent kill of colony-forming cells (CFC). It was also found that the effects of irradiation on colony formation were not confined to CFC kill since medium conditioned by cells during irradiation exhibited stimulatory and inhibitory properties after treatment by 600 and 1000 rads, respectively. Studies in which irradiated cells were pretreated with hydroxyurea indicated that CFC in the DNA synthetic phase of the cell cycle were particularly sensitive to low doses of irradiation. The proliferative capacity of CFC surviving 1000 rads was undiminished as judged by their ability to form large colonies. Estimates of CFC kill by hydroxyurea were also affected by the level of CSA

A critical number of workers in a honeybee colony triggers investment in reproduction.

Science.gov (United States)

Smith, Michael L; Ostwald, Madeleine M; Loftus, J Carter; Seeley, Thomas D

2014-10-01

Social insect colonies, like individual organisms, must decide as they develop how to allocate optimally their resources among survival, growth, and reproduction. Only when colonies reach a certain state do they switch from investing purely in survival and growth to investing also in reproduction. But how do worker bees within a colony detect that their colony has reached the state where it is adaptive to begin investing in reproduction? Previous work has shown that larger honeybee colonies invest more in reproduction (i.e., the production of drones and queens), however, the term 'larger' encompasses multiple colony parameters including number of adult workers, size of the nest, amount of brood, and size of the honey stores. These colony parameters were independently increased in this study to test which one(s) would increase a colony's investment in reproduction via males. This was assayed by measuring the construction of drone comb, the special type of comb in which drones are reared. Only an increase in the number of workers stimulated construction of drone comb. Colonies with over 4,000 workers began building drone comb, independent of the other colony parameters. These results show that attaining a critical number of workers is the key parameter for honeybee colonies to start to shift resources towards reproduction. These findings are relevant to other social systems in which a group's members must adjust their behavior as a function of the group's size.

A critical number of workers in a honeybee colony triggers investment in reproduction

Science.gov (United States)

Smith, Michael L.; Ostwald, Madeleine M.; Loftus, J. Carter; Seeley, Thomas D.

2014-10-01

Social insect colonies, like individual organisms, must decide as they develop how to allocate optimally their resources among survival, growth, and reproduction. Only when colonies reach a certain state do they switch from investing purely in survival and growth to investing also in reproduction. But how do worker bees within a colony detect that their colony has reached the state where it is adaptive to begin investing in reproduction? Previous work has shown that larger honeybee colonies invest more in reproduction (i.e., the production of drones and queens), however, the term `larger' encompasses multiple colony parameters including number of adult workers, size of the nest, amount of brood, and size of the honey stores. These colony parameters were independently increased in this study to test which one(s) would increase a colony's investment in reproduction via males. This was assayed by measuring the construction of drone comb, the special type of comb in which drones are reared. Only an increase in the number of workers stimulated construction of drone comb. Colonies with over 4,000 workers began building drone comb, independent of the other colony parameters. These results show that attaining a critical number of workers is the key parameter for honeybee colonies to start to shift resources towards reproduction. These findings are relevant to other social systems in which a group's members must adjust their behavior as a function of the group's size.

Clinical Outcomes Among Children With Standard-Risk Medulloblastoma Treated With Proton and Photon Radiation Therapy: A Comparison of Disease Control and Overall Survival

International Nuclear Information System (INIS)

Eaton, Bree R.; Esiashvili, Natia; Kim, Sungjin; Weyman, Elizabeth A.; Thornton, Lauren T.; Mazewski, Claire; MacDonald, Tobey; Ebb, David; MacDonald, Shannon M.; Tarbell, Nancy J.; Yock, Torunn I.

2016-01-01

Purpose: The purpose of this study was to compare long-term disease control and overall survival between children treated with proton and photon radiation therapy (RT) for standard-risk medulloblastoma. Methods and Materials: This multi-institution cohort study includes 88 children treated with chemotherapy and proton (n=45) or photon (n=43) RT between 2000 and 2009. Overall survival (OS), recurrence-free survival (RFS), and patterns of failure were compared between the 2 cohorts. Results: Median (range) age was 6 years old at diagnosis (3-21 years) for proton patients versus 8 years (3-19 years) for photon patients (P=.011). Cohorts were similar with respect to sex, histology, extent of surgical resection, craniospinal irradiation (CSI) RT dose, total RT dose, whether the RT boost was delivered to the posterior fossa (PF) or tumor bed (TB), time from surgery to RT start, or total duration of RT. RT consisted of a median (range) CSI dose of 23.4 Gy (18-27 Gy) and a boost of 30.6 Gy (27-37.8 Gy). Median follow-up time is 6.2 years (95% confidence interval [CI]: 5.1-6.6 years) for proton patients versus 7.0 years (95% CI: 5.8-8.9 years) for photon patients. There was no significant difference in RFS or OS between patients treated with proton versus photon RT; 6-year RFS was 78.8% versus 76.5% (P=.948) and 6-year OS was 82.0% versus 87.6%, respectively (P=.285). On multivariate analysis, there was a trend for longer RFS with females (P=.058) and higher CSI dose (P=.096) and for longer OS with females (P=.093). Patterns of failure were similar between the 2 cohorts (P=.908). Conclusions: Disease control with proton and photon radiation therapy appears equivalent for standard risk medulloblastoma.

Energy related germination and survival rates of water-imbibed Arabidopsis seeds irradiated with protons

International Nuclear Information System (INIS)

Qin, H.L.; Xue, J.M.; Lai, J.N.; Wang, J.Y.; Zhang, W.M.; Miao, Q.; Yan, S.; Zhao, W.J.; He, F.; Gu, H.Y.; Wang, Y.G.

2006-01-01

In order to investigate the influence of ion energy on the germination and survival rates, water-imbibed Arabidopsis seeds were irradiated with protons in atmosphere. The ion fluence used in this experiment was in the range of 4 x 10 9 -1 x 10 14 ions/cm 2 . The ion energy is from 1.1 MeV to 6.5 MeV. According to the structure of the seed and TRIM simulation, the ions with the energy of 6.5 MeV can irradiate the shoot apical meristem directly whereas the ions with the energy of 1.1 MeV cannot. The results showed that both the germination and survival rates decrease while increasing the ion fluence, and the fluence-respond curve for each energy has different character. Besides the shoot apical meristem (SAM), which is generally considered as the main radiobiological target, the existence of a secondary target around SAM is proposed in this paper

Energy related germination and survival rates of water-imbibed Arabidopsis seeds irradiated with protons

Energy Technology Data Exchange (ETDEWEB)

Qin, H.L. [Key Laboratory of Heavy Ion Physics, MOE, Peking University, Beijing 100871 (China); Xue, J.M. [Key Laboratory of Heavy Ion Physics, MOE, Peking University, Beijing 100871 (China); Lai, J.N. [Key Laboratory of Heavy Ion Physics, MOE, Peking University, Beijing 100871 (China); Wang, J.Y. [Key Laboratory of Heavy Ion Physics, MOE, Peking University, Beijing 100871 (China); Zhang, W.M. [Key Laboratory of Heavy Ion Physics, MOE, Peking University, Beijing 100871 (China); Miao, Q. [Key Laboratory of Heavy Ion Physics, MOE, Peking University, Beijing 100871 (China); Yan, S. [Key Laboratory of Heavy Ion Physics, MOE, Peking University, Beijing 100871 (China); Zhao, W.J. [Key Laboratory of Heavy Ion Physics, MOE, Peking University, Beijing 100871 (China); He, F. [School of Life Science, Peking University, Beijing 100871 (China); Gu, H.Y. [School of Life Science, Peking University, Beijing 100871 (China); Wang, Y.G. [Key Laboratory of Heavy Ion Physics, MOE, Peking University, Beijing 100871 (China)]. E-mail: ygwang@pku.edu.cn

2006-04-15

In order to investigate the influence of ion energy on the germination and survival rates, water-imbibed Arabidopsis seeds were irradiated with protons in atmosphere. The ion fluence used in this experiment was in the range of 4 x 10{sup 9}-1 x 10{sup 14} ions/cm{sup 2}. The ion energy is from 1.1 MeV to 6.5 MeV. According to the structure of the seed and TRIM simulation, the ions with the energy of 6.5 MeV can irradiate the shoot apical meristem directly whereas the ions with the energy of 1.1 MeV cannot. The results showed that both the germination and survival rates decrease while increasing the ion fluence, and the fluence-respond curve for each energy has different character. Besides the shoot apical meristem (SAM), which is generally considered as the main radiobiological target, the existence of a secondary target around SAM is proposed in this paper.

Risk indicators affecting honeybee colony survival in Europe: one year of surveillance

DEFF Research Database (Denmark)

Jacques, Antoine; Laurent, Marion; Bougeard, Stéphanie

2016-01-01

The first pan-European harmonized active epidemiological surveillance program on honeybee colony mortality (EPILOBEE) was set up across 17 European Member States to estimate honeybee colony mortality over winter and during the beekeeping season. In nine Member States, overwinter losses were higher...... and statistically different from the empirical level of 10 % under which the level of overwinter mortality was considered as acceptable with usual beekeeping conditions. In four other countries, these losses were lower. Using multivariable Poisson regression models, it was showed that the size of the operation...

Ratios of colony mass to thermal conductance of tree and man-made nest enclosures of Apis mellifera: implications for survival, clustering, humidity regulation and Varroa destructor

Science.gov (United States)

Mitchell, Derek

2016-05-01

In the absence of human intervention, the honeybee ( Apis mellifera L.) usually constructs its nest in a tree within a tall, narrow, thick-walled cavity high above the ground (the enclosure); however, most research and apiculture is conducted in the thin-walled, squat wooden enclosures we know as hives. This experimental research, using various hives and thermal models of trees, has found that the heat transfer rate is approximately four to seven times greater in the hives in common use, compared to a typical tree enclosure in winter configuration. This gives a ratio of colony mass to lumped enclosure thermal conductance (MCR) of less than 0.8 kgW-1 K for wooden hives and greater than 5 kgW-1 K for tree enclosures. This result for tree enclosures implies higher levels of humidity in the nest, increased survival of smaller colonies and lower Varroa destructor breeding success. Many honeybee behaviours previously thought to be intrinsic may only be a coping mechanism for human intervention; for example, at an MCR of above 2 kgW-1 K, clustering in a tree enclosure may be an optional, rare, heat conservation behaviour for established colonies, rather than the compulsory, frequent, life-saving behaviour that is in the hives in common use. The implied improved survival in hives with thermal properties of tree nests may help to solve some of the problems honeybees are currently facing in apiculture.

Lifetime effects of single-event proton exposures in rhesus monkeys

International Nuclear Information System (INIS)

Wood, D.H.; Yochmowitz, M.G.; Salmon, Y.L.

1986-01-01

The US School of Aerospace Medicine studies of the lifetime effects of proton irradiation in rhesus monkeys have been conducted. Life-span shortening has been associated with proton energies of 55 MeV and above, as well as with doses greater than 360 rads. Female rhesus monkeys have a higher mortality than males as a result of high incidence of endometriosis in the irradiated animals. A dose ordering effect is apparent. Mortality rates began to accelerate at eight years after doses of 360 to 400 rads; at two years, after 500 to 650 rads; and less than one year, after 800 rads. Malignant tumors accounted for 18% of the deaths in the proton-exposed animals. Endometriosis was the cause of 25% of the deaths in this group. Energy-specific effects were observed. Eight malignant brain tumors occurred in animals exposed to 55-MeV protons and in no other group. Cataract incidence was highest in animals exposed to 32 and 55 MeV. These observations suggest a positive relationship with the Bragg peak energy distribution in the area of the brain and crystalline lens. Glucose tolerance was lowest in the animals exposed to totally penetrating radiation, where the fraction of the surface dose reaching the pancreas was highest. Age-matched control animals have yet to pass their median survival time, and the colony continues to be a valuable source of data on the relationship of total-body radiation to age-related diseases in captive monkeys. 16 refs., 6 figs., 5 tabs

Virus Status, Varroa Levels, and Survival of 20 Managed Honey Bee Colonies Monitored in Luxembourg Between the Summer of 2011 and the Spring of 2013

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Clermont Antoine

2015-06-01

Full Text Available Twenty managed honey bee colonies, split between 5 apiaries with 4 hives each, were monitored between the summer of 2011 and spring of 2013. Living bees were sampled in July 2011, July 2012, and August 2012. Twenty-five, medium-aged bees, free of varroa mites, were pooled per colony and date, to form one sample. Unlike in France and Belgium, Chronic Bee Paralysis Virus (CBPV has not been found in Luxembourg. Slow Bee Paralysis Virus (SBPV and Israeli Acute Paralysis Virus (IAPV levels were below detection limits. Traces of Kashmir Bee Virus (KBV were amplified. Black Queen Cell Virus (BQCV, Varroa destructor Virus-1 (VDV-1, and SacBrood Virus (SBV were detected in all samples and are reported from Luxembourg for the first time. Varroa destructor Macula- Like Virus (VdMLV, Deformed Wing Virus (DWV, and Acute Bee Paralysis Virus (ABPV were detected at all locations, and in most but not all samples. There was a significant increase in VDV-1 and DWV levels within the observation period. A principal component analysis was unable to separate the bees of colonies that survived the following winter from bees that died, based on their virus contents in summer. The number of dead varroa mites found below colonies was elevated in colonies that died in the following winter. Significant positive relationships were found between the log-transformed virus levels of the bees and the log-transformed number of mites found below the colonies per week, for VDV-1 and DWV. Sacbrood virus levels were independent of varroa levels, suggesting a neutral or competitive relationship between this virus and varroa.

Colony form variation of Bacillus pumilus E601 after cultured and neutron irradiation

International Nuclear Information System (INIS)

Chen Xiaoming; Wei Baoli; Zhang Jianguo

2008-01-01

The distribution of two colony forms of Bacillus pumilus E601 and the effect of neutron irradiation on the colony form were reported. The translucent and opaque colonies were cultured several generations to observe the proportion of two form colonies. The spores of opaque colony were irradiated at 80, 800 and 2000 Gy of fast neutron from CFBR-II pulse pile, and the survivors of opaque colony were irradiated again at the same doses. The results showed that: (1) Bacillus pumilus E601 observed two types of colony form: translucent and opaque colony; (2) the translucent colony could produce both translucent and opaque colonies in equal, while the opaque colony couldn't produce translucent colony generally; (3) neutron irradiation could affect the colony form distribution. The ratio of survival translucent colony was increased with the increase of the first neutron irradiation doses, and the second neutron irradiation also increased the ratio of translucent colony. It was concluded that the instability of translucent colony was the main reason to produce two colony forms of Bacillus pumilus E601. The strain of translucent colony had a stronger ability to resist neutron irradiation than the opaque colony. (authors)

WE-E-BRE-07: High-Throughput Mapping of Proton Biologic Effect

Energy Technology Data Exchange (ETDEWEB)

Bronk, L; Guan, F; Kerr, M; Dinh, J; Titt, U; Mirkovic, D; Lin, S; Mohan, R; Grosshans, D [UT MD Anderson Cancer Center, Houston, TX (United States)

2014-06-15

Purpose: To systematically relate the relative biological effectives (RBE) of proton therapy to beam linear energy transfer (LET) and dose. Methods: Using a custom irradiation apparatus previously characterized by our group, H460 NSCLCs were irradiated using a clinical 80MeV spot scanning proton beam. Utilizing this system allowed for high-throughput clonogenic assays performed in 96-well tissue culture plates as opposed to the traditional 6-well technique. Each column in the 96-well plate received a set LET-dose combination. By altering the total number of dose repaintings, numerous dose-LET configurations were examined to effectively generate surviving fraction (SF) data over the entire Bragg peak. The clonogenic assay was performed post-irradiation using an INCell Analyzer for colony quantification. SF data were fit to the linear-quadratic model for analysis. Results: Irradiation with increasing LETs resulted in decreased cell survival largely independent of dose. A significant correlation between LET and SF was identified by two-way ANOVA and the extra sum-of-squares F test. This trend was obscured at the lower LET values in the plateau region of the Bragg peak; however, it was clear for LET values at and beyond the Bragg peak. Data fits revealed the SF at a dose of 2Gy (SF2) to be 0.48 for the lowest tested LET (1.55keV/um), 0.47 at the end of the plateau region (4.74keV/um) and 0.33 for protons at the Bragg peak (10.35keV/um). Beyond the Bragg peak we measured SF2s of 0.16 for 15.01keV/um, 0.02 for 16.79keV/um, and 0.004 for 18.06keV/um. Conclusion: We have shown that our methodology enables high-content automated screening for proton irradiations over a range of LETs. The observed decrease in cellular SF in high LET regions confirms an increased RBE of the radiation and suggests further evaluation of proton RBE values is necessary to optimize clinical outcomes. Rosalie B. Hite Graduate Fellowship in Cancer Research, NIH Program Project Grant P01CA021239.

Social Immunity: Emergence and Evolution of Colony-Level Disease Protection.

Science.gov (United States)

Cremer, Sylvia; Pull, Christopher D; Fürst, Matthias A

2018-01-07

Social insect colonies have evolved many collectively performed adaptations that reduce the impact of infectious disease and that are expected to maximize their fitness. This colony-level protection is termed social immunity, and it enhances the health and survival of the colony. In this review, we address how social immunity emerges from its mechanistic components to produce colony-level disease avoidance, resistance, and tolerance. To understand the evolutionary causes and consequences of social immunity, we highlight the need for studies that evaluate the effects of social immunity on colony fitness. We discuss the roles that host life history and ecology have on predicted eco-evolutionary dynamics, which differ among the social insect lineages. Throughout the review, we highlight current gaps in our knowledge and promising avenues for future research, which we hope will bring us closer to an integrated understanding of socio-eco-evo-immunology.

Relative survival of hybrid x-ray-resistant, and normally sensitive mammalian cells exposed to x rays and protons under aerobic and hypoxic conditions

International Nuclear Information System (INIS)

Williams, J.R.; Gould, R.G.; Flynn, D.; Robertson, J.B.; Little, J.B.

1978-01-01

Survival of an x-ray-resistant hybrid cell line (HD 1 ) and a normally responsive cell line (H 4 ) have been compared when irradiated under induced hypoxia by both protons and X rays. The two cell lines are similarly protected when irradiated under hypoxic conditions with oxygen enhancement ratios of 2.8 and 2.7, respectively. The protection is consistent with a dose-modifying factor. No statistically significant difference is observed between cell inactivation by x rays and protons in either cell line, whether irradiated under aerobic or hypoxic conditions

Brood temperature, task division and colony survival in honeybees : A model

NARCIS (Netherlands)

Becher, Matthias A.; Hildenbrandt, Hanno; Hemelrijk, Charlotte K.; Moritz, Robin F. A.

2010-01-01

One of the mechanisms by which honeybees regulate division of labour among their colony members is age polyethism. Here the younger bees perform in-hive tasks such as heating and the older ones carry out tasks outside the hive such as foraging. Recently it has been shown that the higher

Population Change in a Marine Bird Colony is Driven By Changes in Recruitment

Directory of Open Access Journals (Sweden)

Anthony J. Gaston

2011-12-01

Full Text Available The population dynamics of long-lived birds are thought to be very sensitive to changes in adult survival. However, where natal philopatry is low, recruitment from the larger metapopulation may have the strongest effect on population growth rate even in long-lived species. Here, we illustrate such a situation where changes in a seabird colony size appeared to be the consequence of changes in recruitment. We studied the population dynamics of a declining colony of Ancient Murrelets (Synthliboramphus antiquus at East Limestone Island, British Columbia. During 1990-2010, Ancient Murrelet chicks were trapped at East Limestone Island while departing to sea, using a standard trapping method carried on throughout the departure period. Adult murrelets were trapped while departing from the colony during 1990-2003. Numbers of chicks trapped declined during 1990-1995, probably because of raccoon predation, increased slightly from 1995-2000 and subsequently declined again. Reproductive success was 30% lower during 2000-2003 than in earlier years, mainly because of an increase in desertions. The proportion of nonbreeders among adult birds trapped at night also declined over the study period. Mortality of adult birds, thought to be mainly prebreeders, from predators more than doubled over the same period. Apparent adult survival of breeders remained constant during 1991-2002 once the first year after banding was excluded, but the apparent survival rates in the first year after banding fell and the survival of birds banded as chicks to age three halved over the same period. A matrix model of population dynamics suggested that even during the early part of the study immigration from other breeding areas must have been substantial, supporting earlier observations that natal philopatry in this species is low. The general colony decline after 2000 probably was related to diminished recruitment, as evidenced by the lower proportion of nonbreeders in the trapped

Fluctuating survival selection explains variation in avian group size.

Science.gov (United States)

Brown, Charles R; Brown, Mary Bomberger; Roche, Erin A; O'Brien, Valerie A; Page, Catherine E

2016-05-03

Most animal groups vary extensively in size. Because individuals in certain sizes of groups often have higher apparent fitness than those in other groups, why wide group size variation persists in most populations remains unexplained. We used a 30-y mark-recapture study of colonially breeding cliff swallows (Petrochelidon pyrrhonota) to show that the survival advantages of different colony sizes fluctuated among years. Colony size was under both stabilizing and directional selection in different years, and reversals in the sign of directional selection regularly occurred. Directional selection was predicted in part by drought conditions: birds in larger colonies tended to be favored in cooler and wetter years, and birds in smaller colonies in hotter and drier years. Oscillating selection on colony size likely reflected annual differences in food availability and the consequent importance of information transfer, and/or the level of ectoparasitism, with the net benefit of sociality varying under these different conditions. Averaged across years, there was no net directional change in selection on colony size. The wide range in cliff swallow group size is probably maintained by fluctuating survival selection and represents the first case, to our knowledge, in which fitness advantages of different group sizes regularly oscillate over time in a natural vertebrate population.

Inhibitory Effects of Salinomycin on Cell Survival, Colony Growth, Migration, and Invasion of Human Non-Small Cell Lung Cancer A549 and LNM35: Involvement of NAG-1.

Directory of Open Access Journals (Sweden)

Kholoud Arafat

Full Text Available A major challenge for oncologists and pharmacologists is to develop more potent and less toxic drugs that will decrease the tumor growth and improve the survival of lung cancer patients. Salinomycin is a polyether antibiotic used to kill gram-positive bacteria including mycobacteria, protozoans such as plasmodium falciparum, and the parasites responsible for the poultry disease coccidiosis. This old agent is now a serious anti-cancer drug candidate that selectively inhibits the growth of cancer stem cells. We investigated the impact of salinomycin on survival, colony growth, migration and invasion of the differentiated human non-small cell lung cancer lines LNM35 and A549. Salinomycin caused concentration- and time-dependent reduction in viability of LNM35 and A549 cells through a caspase 3/7-associated cell death pathway. Similarly, salinomycin (2.5-5 µM for 7 days significantly decreased the growth of LNM35 and A549 colonies in soft agar. Metastasis is the main cause of death related to lung cancer. In this context, salinomycin induced a time- and concentration-dependent inhibition of cell migration and invasion. We also demonstrated for the first time that salinomycin induced a marked increase in the expression of the pro-apoptotic protein NAG-1 leading to the inhibition of lung cancer cell invasion but not cell survival. These findings identify salinomycin as a promising novel therapeutic agent for lung cancer.

Radiosensitivity of Patient-Derived Glioma Stem Cell 3-Dimensional Cultures to Photon, Proton, and Carbon Irradiation

Energy Technology Data Exchange (ETDEWEB)

Chiblak, Sara; Tang, Zili [German Cancer Consortium, Heidelberg (Germany); Molecular and Translational Radiation Oncology, Heidelberg Ion Therapy Center, Heidelberg Institute of Radiation Oncology, University of Heidelberg Medical School and National Center for Tumor Diseases, German Cancer Research Center, Heidelberg (Germany); Campos, Benito; Gal, Zoltan; Unterberg, Andreas [Division of Neurological Research, Department of Neurosurgery, University of Heidelberg Medical School, Heidelberg (Germany); Debus, Jürgen [German Cancer Consortium, Heidelberg (Germany); Molecular and Translational Radiation Oncology, Heidelberg Ion Therapy Center, Heidelberg Institute of Radiation Oncology, University of Heidelberg Medical School and National Center for Tumor Diseases, German Cancer Research Center, Heidelberg (Germany); Herold-Mende, Christel [Division of Neurological Research, Department of Neurosurgery, University of Heidelberg Medical School, Heidelberg (Germany); Abdollahi, Amir, E-mail: a.amir@dkfz.de [German Cancer Consortium, Heidelberg (Germany); Molecular and Translational Radiation Oncology, Heidelberg Ion Therapy Center, Heidelberg Institute of Radiation Oncology, University of Heidelberg Medical School and National Center for Tumor Diseases, German Cancer Research Center, Heidelberg (Germany)

2016-05-01

Purpose: To investigate the radiosensitivity of primary glioma stem cell (GSC) cultures with different CD133 status in a 3-dimensional (3D) model after photon versus proton versus carbon irradiation. Methods and Materials: Human primary GSC spheroid cultures were established from tumor specimens of six consented glioblastoma patients. Human U87MG was used as a classical glioblastoma radioresistant cell line. Cell suspensions were generated by mechanical dissociation of GSC spheroids and embedded in a semi-solid 3D matrix before irradiation. Spheroid-like colonies were manually counted by microscopy. Cells were also recovered and quantified by fluorescence. CD133 expression and DNA damage were evaluated by flow cytometry. Results: The fraction of CD133{sup +} cells varied between 0.014% and 96% in the six GSC cultures and showed a nonsignificant correlation with plating efficiency and survival fractions. The 4 most photon-radioresistant GSC cultures were NCH644, NCH421k, NCH441, and NCH636. Clonogenic survival for proton irradiation revealed relative biologic effectiveness (RBE) in the range of 0.7-1.20. However, carbon irradiation rendered the photon-resistant GSC cultures sensitive, with average RBE of 1.87-3.44. This effect was partly attributed to impaired capability of GSC to repair carbon ion–induced DNA double-strand breaks as determined by residual DNA repair foci. Interestingly, radiosensitivity of U87 cells was comparable to GSC cultures using clonogenic survival as the standard readout. Conclusions: Carbon irradiation is effective in GSC eradication with similar RBE ranges approximately 2-3 as compared with non-stem GSC cultures (U87). Our data strongly suggest further exploration of GSC using classic radiobiology endpoints such as the here-used 3D clonogenic survival assay and integration of additional GSC-specific markers.

Radiosensitivity of Patient-Derived Glioma Stem Cell 3-Dimensional Cultures to Photon, Proton, and Carbon Irradiation

International Nuclear Information System (INIS)

Chiblak, Sara; Tang, Zili; Campos, Benito; Gal, Zoltan; Unterberg, Andreas; Debus, Jürgen; Herold-Mende, Christel; Abdollahi, Amir

2016-01-01

Purpose: To investigate the radiosensitivity of primary glioma stem cell (GSC) cultures with different CD133 status in a 3-dimensional (3D) model after photon versus proton versus carbon irradiation. Methods and Materials: Human primary GSC spheroid cultures were established from tumor specimens of six consented glioblastoma patients. Human U87MG was used as a classical glioblastoma radioresistant cell line. Cell suspensions were generated by mechanical dissociation of GSC spheroids and embedded in a semi-solid 3D matrix before irradiation. Spheroid-like colonies were manually counted by microscopy. Cells were also recovered and quantified by fluorescence. CD133 expression and DNA damage were evaluated by flow cytometry. Results: The fraction of CD133"+ cells varied between 0.014% and 96% in the six GSC cultures and showed a nonsignificant correlation with plating efficiency and survival fractions. The 4 most photon-radioresistant GSC cultures were NCH644, NCH421k, NCH441, and NCH636. Clonogenic survival for proton irradiation revealed relative biologic effectiveness (RBE) in the range of 0.7-1.20. However, carbon irradiation rendered the photon-resistant GSC cultures sensitive, with average RBE of 1.87-3.44. This effect was partly attributed to impaired capability of GSC to repair carbon ion–induced DNA double-strand breaks as determined by residual DNA repair foci. Interestingly, radiosensitivity of U87 cells was comparable to GSC cultures using clonogenic survival as the standard readout. Conclusions: Carbon irradiation is effective in GSC eradication with similar RBE ranges approximately 2-3 as compared with non-stem GSC cultures (U87). Our data strongly suggest further exploration of GSC using classic radiobiology endpoints such as the here-used 3D clonogenic survival assay and integration of additional GSC-specific markers.

Proton dynamics in cancer.

Science.gov (United States)

Huber, Veronica; De Milito, Angelo; Harguindey, Salvador; Reshkin, Stephan J; Wahl, Miriam L; Rauch, Cyril; Chiesi, Antonio; Pouysségur, Jacques; Gatenby, Robert A; Rivoltini, Licia; Fais, Stefano

2010-06-15

Cancer remains a leading cause of death in the world today. Despite decades of research to identify novel therapeutic approaches, durable regressions of metastatic disease are still scanty and survival benefits often negligible. While the current strategy is mostly converging on target-therapies aimed at selectively affecting altered molecular pathways in tumor cells, evidences are in parallel pointing to cell metabolism as a potential Achilles' heel of cancer, to be disrupted for achieving therapeutic benefit. Critical differences in the metabolism of tumor versus normal cells, which include abnormal glycolysis, high lactic acid production, protons accumulation and reversed intra-extracellular pH gradients, make tumor site a hostile microenvironment where only cancer cells can proliferate and survive. Inhibiting these pathways by blocking proton pumps and transporters may deprive cancer cells of a key mechanism of detoxification and thus represent a novel strategy for a pleiotropic and multifaceted suppression of cancer cell growth.Research groups scattered all over the world have recently started to investigate various aspects of proton dynamics in cancer cells with quite encouraging preliminary results. The intent of unifying investigators involved in this research line led to the formation of the "International Society for Proton Dynamics in Cancer" (ISPDC) in January 2010. This is the manifesto of the newly formed society where both basic and clinical investigators are called to foster translational research and stimulate interdisciplinary collaboration for the development of more specific and less toxic therapeutic strategies based on proton dynamics in tumor cell biology.

Colonial Figures: Memories of Street Traders in the Colonial and Early Post-colonial Periods

Directory of Open Access Journals (Sweden)

Sheri Lynn Gibbings

2012-12-01

Full Text Available This article explores post-colonial memories about street traders among individuals who lived in the former colony of the Dutch East Indies. It argues that these narratives romanticize the relationship between Europeans and indigenous peoples. Street vendors are also used to differentiate between periods within colonial and post-colonial history. The nostalgic representation of interracial contact between Europeans and traders is contrasted with representations of other figures such as the Japanese and the nationalist. A recurring feature of these representations is the ability of Europeans to speak with street traders and imagine what they wanted and needed. The traders are remembered as a social type that transgressed politics and represented the neutrality of the economic sphere as a place for shared communication. The article concludes that the figure of the street vendor contributes to the nostalgic reinvention of the colony but is also used in narratives to differentiate between and mark changes across the colonial and post-colonial periods.

Environmental influences on Adelie penguin breeding schedules, endocrinology, and chick survival.

Science.gov (United States)

Ninnes, C E; Waas, J R; Ling, N; Nakagawa, S; Banks, J C; Bell, D G; Bright, A; Carey, P W; Chandler, J; Hudson, Q J; Ingram, J R; Lyall, K; Morgan, D K J; Stevens, M I; Wallace, J; Möstl, E

2011-08-01

To understand how the social and physical environment influences behaviour, reproduction and survival, studies of underlying hormonal processes are crucial; in particular, interactions between stress and reproductive responses may have critical influences on breeding schedules. Several authors have examined the timing of breeding in relation to environmental stimuli, while others have independently described endocrine profiles. However, few studies have simultaneously measured endocrine profiles, breeding behaviour, and offspring survival across seasons. We measured sex and stress hormone concentrations (oestrogens, testosterone, and corticosterone), timing of breeding, and chick survival, in Adelie penguins (Pygoscelis adeliae) at two colonies in two different years. Clutch initiation at Cape Bird South (CBS; year 1, ~14,000 pairs) occurred later than at Cape Crozier East (CCE; year 2, ~ 25,000 pairs); however, breeding was more synchronous at CBS. This pattern was probably generated by the persistence of extensive sea ice at CBS (year 1). Higher corticosterone metabolite and lower sex hormone concentrations at CBS correlated with later breeding and lower chick survival compared to at CCE - again, a likely consequence of sea ice conditions. Within colonies, sub-colony size (S, 50-100; M, 200-300; L, 500-600; XL, >1000 pairs) did not influence the onset or synchrony of breeding, chick survival, or hormone concentrations. We showed that the endocrine profiles of breeding Adelie penguins can differ markedly between years and/or colonies, and that combining measures of endocrinology, behaviour, and offspring survival can reveal the mechanisms and consequences that different environmental conditions can have on breeding ecology. Copyright © 2011 Elsevier Inc. All rights reserved.

Method of monolayer cultures of the guinea pig spleen used to evaluate the radioprotective action of mexamine on the survival of colony-forming cells. [Method of monolayer cultures, quantitative estimation of radioprotective action of drugs

Energy Technology Data Exchange (ETDEWEB)

Baisogolov, G D; Rudakova, S F; Rudakov, I A; Konoplyannikov, A G [Akademiya Meditsinskikh Nauk SSSR, Obninsk. Nauchno-Issledovatel' skij Inst. Meditsinskoj Radiologii

1976-01-01

Dose dependent survival of colony-forming splenic cells of guinea pigs has been studied after ..gamma..-irradiation in vitro. The average lethal dose (D/sub 0/) for colony-forming cells is 245 rads, the extrapolation number - 1.5. Radiosensitivity of the splenic cells is markedly lower than that of the bone marrow cells (128 rads). After intraperitoneal administration of mexamine (150 mg/kg) to guinea pigs 10-15 min before irradiation, D/sub 0/ increases up to 319 rads, extrapolation number is 1.4, and DRF is 1.3.

Population and colony-level determinants of tertiary sex ratio in the declining barn swallow.

Directory of Open Access Journals (Sweden)

Nicola Saino

Full Text Available Sex ratio of adults (tertiary sex ratio, TSR is a major feature of animal populations with consequences for their behaviour, genetic structure and viability. Spatial and temporal variation in TSR occurs within species but the mechanisms behind it are poorly understood. In this long-term study of a declining population of a socially monogamous, colonial, migratory bird, the barn swallow (Hirundo rustica, we first analyzed population-level variation in TSR ( =  proportion of males of yearlings at sexual maturation in relation to ecological conditions as gauged by annual survival rate of adults. TSR was male-biased both among yearlings and older individuals, but male bias of yearlings was more pronounced after years with larger decline in adult survival. Thus, male offspring were less susceptible to the adverse ecological conditions that cause increased mortality. Dispersal and settling site decisions can have major consequences on fitness via the effects of local TSR on mating and sperm competition. Breeding barn swallows are highly philopatric while natal dispersal is high and, together with mortality, is the main determinant of colony TSR. We thus also investigated the mechanisms of breeding colony choice by yearlings and found that TSR of new-settlers in a given colony and year was negatively predicted by TSR of returning, early arriving older individuals in that year, but not by overall TSR at the colony in the previous year. This suggests that in our male-biased population new-settler males respond to local TSR upon arrival to choose the sites with larger breeding opportunities. Hence, variation in ecological conditions as reflected by adult survival can shift the TSR of individuals recruiting into a local population, with potentially various demographic consequences. However, breeding site choice based on TSR tends to homogenize TSR at a population level likely by facilitating settling of dispersing males in colonies with less male

MeV single-ion beam irradiation of mammalian cells using the Surrey vertical nanobeam, compared with broad proton beam and X-ray irradiations

Energy Technology Data Exchange (ETDEWEB)

Prakrajang, K. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Faculty of Science, Maejo University, Chiang Mai 50290 (Thailand); Jeynes, J.C.G.; Merchant, M.J.; Kirkby, K.; Kirkby, N. [Surrey Ion Beam Center, Faculty of Engineering and Physical Science, University of Surrey, Guildford Surrey, GU2 7XH (United Kingdom); Thopan, P. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Yu, L.D., E-mail: yuld@fnrf.science.cmu.ac.th [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand)

2013-07-15

Highlights: •Recently completed nanobeam at the Surrey Ion Beam Centre was used. •3.8-MeV single and broad proton beams irradiated Chinese hamster cells. •Cell survival curves were measured and compared with 300-kV X-ray irradiation. •Single ion irradiation had a lower survival part at ultra-low dose. •It implies hypersensitivity, bystander effect and cell cycle phase of cell death. -- Abstract: As a part of a systematic study on mechanisms involved in physical cancer therapies, this work investigated response of mammalian cells to ultra-low-dose ion beam irradiation. The ion beam irradiation was performed using the recently completed nanobeam facility at the Surrey Ion Beam Centre. A scanning focused vertical ion nano-beam was applied to irradiate Chinese hamster V79 cells. The V79 cells were irradiated in two different beam modes, namely, focused single ion beam and defocused scanning broad ion beam of 3.8-MeV protons. The single ion beam was capable of irradiating a single cell with a precisely controlled number of the ions to extremely low doses. After irradiation and cell incubation, the number of surviving colonies as a function of the number of the irradiating ions was measured for the cell survival fraction curve. A lower survival for the single ion beam irradiation than that of the broad beam case implied the hypersensitivity and bystander effect. The ion-beam-induced cell survival curves were compared with that from 300-kV X-ray irradiation. Theoretical studies indicated that the cell death in single ion irradiation mainly occurred in the cell cycle phases of cell division and intervals between the cell division and the DNA replication. The success in the experiment demonstrated the Surrey vertical nanobeam successfully completed.

Proton dynamics in cancer

Directory of Open Access Journals (Sweden)

Pouysségur Jacques

2010-06-01

Full Text Available Abstract Cancer remains a leading cause of death in the world today. Despite decades of research to identify novel therapeutic approaches, durable regressions of metastatic disease are still scanty and survival benefits often negligible. While the current strategy is mostly converging on target-therapies aimed at selectively affecting altered molecular pathways in tumor cells, evidences are in parallel pointing to cell metabolism as a potential Achilles' heel of cancer, to be disrupted for achieving therapeutic benefit. Critical differences in the metabolism of tumor versus normal cells, which include abnormal glycolysis, high lactic acid production, protons accumulation and reversed intra-extracellular pH gradients, make tumor site a hostile microenvironment where only cancer cells can proliferate and survive. Inhibiting these pathways by blocking proton pumps and transporters may deprive cancer cells of a key mechanism of detoxification and thus represent a novel strategy for a pleiotropic and multifaceted suppression of cancer cell growth. Research groups scattered all over the world have recently started to investigate various aspects of proton dynamics in cancer cells with quite encouraging preliminary results. The intent of unifying investigators involved in this research line led to the formation of the "International Society for Proton Dynamics in Cancer" (ISPDC in January 2010. This is the manifesto of the newly formed society where both basic and clinical investigators are called to foster translational research and stimulate interdisciplinary collaboration for the development of more specific and less toxic therapeutic strategies based on proton dynamics in tumor cell biology.

Family strategies against the jesuits in colonial Argentina: Catamarca, 1683-1767

Directory of Open Access Journals (Sweden)

Jorge Troisi Melean

2012-11-01

Full Text Available Based on a lawsuit, I will conduct a detailed study of the strategies of Catamarca´s colonial settlers to deal with Society of Jesus, the most powerful institution of the time.Three families were fighting for survival in a small colonial town in a middle of intercontinental fight between a forceful Spanish Crown and a hesitant Catholic Church. In the gaps of that struggle, each family negotiated their identity against a multiplicity of interests in play, seeking the best of possibilities in a world that was rapidly changing.

Predation of artificial ground nests on white-tailed prairie dog colonies

Science.gov (United States)

Baker, B.W.; Stanley, T.R.; Sedgwick, J.A.

1999-01-01

Prairie dog (Cynomys spp.) colonies are unique to prairie and shrub-steppe landscapes. However, widespread eradication, habitat loss, and sylvatic plague (Yersinia pestis) have reduced their numbers by 98% since historical times. Birds associated with prairie dogs also are declining. Potential nest predators, such as coyotes (Canis latrans), swift foxes (Vulpes velox), and badgers (Taxidea taxus), may be attracted to colonies where a high concentration of prairie dogs serve as available prey. Increased abundance of small mammals, including prairie dogs, also may increase the risk of predation for birds nesting on colonies. Finally, because grazing by prairie dogs may decrease vegetation height and canopy cover, bird nests may be easier for predators to locate. In this study, we placed 1,444 artificial ground nests on and off 74 white-tailed prairie dog (C. leucurus) colonies to test the hypothesis that nest predation rates are higher on colonies than at nearby off sites (i.e., uncolonized habitat). We sampled colonies from 27 May to 16 July 1997 at the following 3 complexes: Coyote Basin, Utah and Colorado; Moxa Arch, Wyoming; and Shirley Basin, Wyoming. Differences in daily predation rates between colonies and paired off sites averaged 1.0% (P = 0.060). When converted to a typical 14-day incubation period, predation rates averaged 14% higher on colonies (57.7 ?? 2.7%; ?? ?? SE) than at off sites (50.4 ?? 3.1%). Comparisons of habitat variables on colonies to off sites showed percent canopy cover of vegetation was similar (P = 0.114), percent bare ground was higher on colonies (P 0.288). Although we found the risk of nest predation was higher on white-tailed prairie dog colonies than at off sites, fitness of birds nesting on colonies might depend on other factors that influence foraging success, reproductive success, or nestling survival.

Agar Technique for the Cultivation In Vitro of Bone-Marrow Colonies

Energy Technology Data Exchange (ETDEWEB)

Metcalf, D. [Walter and Eliza Hall Institute, Royal Melbourne Hospital, Melbourne, VIC (Australia)

1969-07-15

In solid-state agar cultures certain haemopoietic cells proliferate and form discrete colonies of 200 - 4000 cells. Colony formation is dependent on stimulation by the colony-stimulating factor, and this is achieved by (1) the use of a cell feeder layer, (2) the addition of conditioned medium, or (3) the addition of human or mouse serum or urine containing the factor. All colonies initially contain granulocytic cells which differentiate from myeloblasts to polymorphs as colony growth proceeds. Later colonies develop a second population of phagocytic mononuclear cells (macrophages). The colony-forming-system is simple, readily quantitated and highly reproducible. Linear dose responses occur between the dose of colony-stimulating factor and the number and size of colonies developing from a standard number of bone-marrow cells. In-vitro colony formation has been achieved with haemopoietic cells of the following species: mouse, rat, hamster, guinea pig, rabbit and human. In the adult mouse, colony-forming cells are located in the bone marrow, spleen and blood and in the embryo, in the yolk sac, liver and spleen. The colony-forming cell appears to be an early member of the granulocytic series. The colony-forming system has been used as a quantitative assay system: (1) to assay levels of colony-stimulating factor in serum and urine and in the chemical- characterization and purification of the factor; and (2) to enumerate the number of colony-forming cells in haemopoietic tissues in response to a variety of experimental procedures and disease states. Since the system is applicable to human bone-marrow cells, it should prove of value in the quantitative assay of (1) survival of human bone marrow on storage, and (2) bone-marrow content of granulocytic precursor cells in various disease states and following various types of therapy. The system is not suitable for the mass production in vitro of haemopoietic cells for therapeutic use. (author)

Winter Survival of Individual Honey Bees and Honey Bee Colonies Depends on Level of Varroa destructor Infestation

NARCIS (Netherlands)

Dooremalen, van C.; Gerritsen, L.J.M.; Cornelissen, B.; Steen, van der J.J.M.; Langevelde, van F.; Blacquiere, T.

2012-01-01

Background: Recent elevated winter loss of honey bee colonies is a major concern. The presence of the mite Varroa destructor in colonies places an important pressure on bee health. V. destructor shortens the lifespan of individual bees, while long lifespan during winter is a primary requirement to

A framework for analysis of abortive colony size distributions using a model of branching processes in irradiated normal human fibroblasts.

Science.gov (United States)

Sakashita, Tetsuya; Hamada, Nobuyuki; Kawaguchi, Isao; Ouchi, Noriyuki B; Hara, Takamitsu; Kobayashi, Yasuhiko; Saito, Kimiaki

2013-01-01

Clonogenicity gives important information about the cellular reproductive potential following ionizing irradiation, but an abortive colony that fails to continue to grow remains poorly characterized. It was recently reported that the fraction of abortive colonies increases with increasing dose. Thus, we set out to investigate the production kinetics of abortive colonies using a model of branching processes. We firstly plotted the experimentally determined colony size distribution of abortive colonies in irradiated normal human fibroblasts, and found the linear relationship on the log-linear or log-log plot. By applying the simple model of branching processes to the linear relationship, we found the persistent reproductive cell death (RCD) over several generations following irradiation. To verify the estimated probability of RCD, abortive colony size distribution (≤ 15 cells) and the surviving fraction were simulated by the Monte Carlo computational approach for colony expansion. Parameters estimated from the log-log fit demonstrated the good performance in both simulations than those from the log-linear fit. Radiation-induced RCD, i.e. excess probability, lasted over 16 generations and mainly consisted of two components in the early (probability over 5 generations, whereas abortive colony size distribution was robust against it. These results suggest that, whereas short-term RCD is critical to the abortive colony size distribution, long-lasting RCD is important for the dose response of the surviving fraction. Our present model provides a single framework for understanding the behavior of primary cell colonies in culture following irradiation.

An observation study on the effects of queen age on some characteristics of honey bee colonies

Directory of Open Access Journals (Sweden)

Ibrahim Çakmak

2010-01-01

Full Text Available This study was conducted to determine the effects of the queen’s age on performance of the honeybee (A. mellifera anatoliaca colonies at nomad beekeeping conditions. Performances of the colonies, which had 0, 1, 2 and 3 year-old queens, were compared. The number of combs, brood areas, wintering ability survival rate and honey yield were determined as performance criteria. The average number of combs with bees throughout the experiment in Group I, Group II, Group III and Group IV was 10.92±0.78, 14.68±0.55, 10.10±0.60, 7.88±0.45 number combs/colony; the average of brood areas was 3078±372.5 cm2, 3668±460.3 cm2, 2215±294.0 cm2, 1665.38±241.8 cm2; the average of wintering ability was 84.3±2.9%, 88.0±3.7%, 46.6±19.0%, 26.8±16.5%; the survival rate was 100%, 100%, 60%, 40%; and the average of honey yields was 31.4±1.89 kg, 41.5±1.05 kg, 20.4±2.62 kg and 12.0±1.41 kg per colony, respectively. A significant and negative correlation between queen age and brood production (r=-80.2, colony strength (r=-62.5, wintering ability (r=-66 and honey yield (r=-75.6 were calculated (P<0.01. The colonies headed by young queens had more brood areas, longer worker colony population, better wintering ability and greater honey yield in comparison to colonies headed by old queens.

National Cancer Database Analysis of Proton Versus Photon Radiation Therapy in Non-Small Cell Lung Cancer

Energy Technology Data Exchange (ETDEWEB)

Higgins, Kristin A., E-mail: kristin.higgins@emory.edu [Department of Radiation Oncology, Emory University, Atlanta, Georgia (United States); Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); O' Connell, Kelli [Rollins School of Public Health, Emory University, Atlanta, Georgia (United States); Liu, Yuan [Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Rollins School of Public Health, Emory University, Atlanta, Georgia (United States); Department of Biostatistics and Bioinformatics, Emory University, Atlanta, Georgia (United States); Gillespie, Theresa W. [Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Department of Surgery, Emory University, Atlanta, Georgia (United States); McDonald, Mark W. [Department of Radiation Oncology, Emory University, Atlanta, Georgia (United States); Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Pillai, Rathi N. [Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Department of Hematology and Medical Oncology, Emory University, Atlanta, Georgia (United States); Patel, Kirtesh R.; Patel, Pretesh R. [Department of Radiation Oncology, Emory University, Atlanta, Georgia (United States); Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Robinson, Clifford G. [Department of Radiation Oncology, Washington University, St. Louis, Missouri (United States); Simone, Charles B. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States); Owonikoko, Taofeek K. [Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Department of Hematology and Medical Oncology, Emory University, Atlanta, Georgia (United States); Belani, Chandra P. [Penn State Hershey Cancer Institute, Pennsylvania University, Hershey, Pennsylvania (United States); and others

2017-01-01

Purpose: To analyze outcomes and predictors associated with proton radiation therapy for non-small cell lung cancer (NSCLC) in the National Cancer Database. Methods and Materials: The National Cancer Database was queried to capture patients with stage I-IV NSCLC treated with thoracic radiation from 2004 to 2012. A logistic regression model was used to determine the predictors for utilization of proton radiation therapy. The univariate and multivariable association with overall survival were assessed by Cox proportional hazards models along with log–rank tests. A propensity score matching method was implemented to balance baseline covariates and eliminate selection bias. Results: A total of 243,822 patients (photon radiation therapy: 243,474; proton radiation therapy: 348) were included in the analysis. Patients in a ZIP code with a median income of <$46,000 per year were less likely to receive proton treatment, with the income cohort of $30,000 to $35,999 least likely to receive proton therapy (odds ratio 0.63 [95% confidence interval (CI) 0.44-0.90]; P=.011). On multivariate analysis of all patients, non-proton therapy was associated with significantly worse survival compared with proton therapy (hazard ratio 1.21 [95% CI 1.06-1.39]; P<.01). On propensity matched analysis, proton radiation therapy (n=309) was associated with better 5-year overall survival compared with non-proton radiation therapy (n=1549), 22% versus 16% (P=.025). For stage II and III patients, non-proton radiation therapy was associated with worse survival compared with proton radiation therapy (hazard ratio 1.35 [95% CI 1.10-1.64], P<.01). Conclusions: Thoracic radiation with protons is associated with better survival in this retrospective analysis; further validation in the randomized setting is needed to account for any imbalances in patient characteristics, including positron emission tomography–computed tomography staging.

Relative biological effectiveness of high energy protons for a human melanoma

International Nuclear Information System (INIS)

Petrovic, I.; Ristic-Fira, A.; Todorovic, D.; Valastro, I.; Cirrone, P.; Cuttone, G.

2005-01-01

Relative biological effectiveness (RBE) for the survival of human melanoma cells induced by high linear energy transfer (LET) protons was investigated. Exponentially growing HTB140 cells were irradiated close to the Bragg peak maximum of the 62 MeV protons, as well as with 60 Co γ-rays, over single doses, ranging from 8-24 Gy. Clonogenic survival and cell viability were assessed up to 48 h post-irradiation, therefore considered as early inactivation effects. Dose dependent cell inactivation induced by high LET protons was observed. Surviving fractions have shown great overlapping with estimated cell viability, both with the increase of dose and with prolonged cell incubation. Evaluated RBEs were higher with the rise of dose, being in the range from 2 to 3. All analyzes performed have demonstrated a very radio-resistant nature of HTB140 melanoma cells. However, high LET protons are able to inactivate these cells in a larger extent compared to the effects of γ-rays. (author)

Changes in learning and foraging behaviour within developing bumble bee (Bombus terrestris colonies.

Directory of Open Access Journals (Sweden)

Lisa J Evans

Full Text Available Organisation in eusocial insect colonies emerges from the decisions and actions of its individual members. In turn, these decisions and actions are influenced by the individual's behaviour (or temperament. Although there is variation in the behaviour of individuals within a colony, we know surprisingly little about how (or indeed if the types of behaviour present in a colony change over time. Here, for the first time, we assessed potential changes in the behavioural type of foragers during colony development. Using an ecologically relevant foraging task, we measured the decision speed and learning ability of bumble bees (Bombus terrestris at different stages of colony development. We determined whether individuals that forage early in the colony life cycle (the queen and early emerging workers behaved differently from workers that emerge and forage at the end of colony development. Whilst we found no overall change in the foraging behaviour of workers with colony development, there were strong differences in foraging behaviour between queens and their workers. Queens appeared to forage more cautiously than their workers and were also quicker to learn. These behaviours could allow queens to maximise their nectar collecting efficiency whilst avoiding predation. Because the foundress queen is crucial to the survival and success of a bumble bee colony, more efficient foraging behaviour in queens may have strong adaptive value.

UV survival of human mycoplasmas

International Nuclear Information System (INIS)

Aoki, Shigeji; Ito, Shoko; Watanabe, Takehiko

1979-01-01

The inactivation by ultraviolet (UV) light irradiation of mycoplasma cells of five human strains was monitored by investigating the colony-forming ability. The survival curves of five strains tested indicated that the cells of Mycoplasma buccale only are single and homogenously susceptible to UV light. The effect of the repair inhibitor, caffeine, on the colony-forming ability of UV-irradiated cells was investigated with M. buccale because of its homogeneous susceptibility to UV light. The colony formation of irradiated cells was markedly depressed by post-irradiation treatment with caffeine at concentration that had little or no effect on the colony formation of unirradiated cells. The colony-forming units (CFU) of UV-irradiated cells which were kept in broth without caffeine in the dark increased without a lag as the time in the dark increased. The colony-forming ability of the irradiated cells completely recovered after 3 hr in the dark. However, when irradiated cells were kept in the presence of caffeine, no increase in their CFU was observed. The mode of action of caffeine on UV-irradiated cells closely resembles that described for other organisms which possess dark reactivation systems for UV-induced damage in deoxyribonucleic acid. Thus, the results obtained provide evidence for the existence of a dark repair function in M. buccale. (author)

Proton-Beam Therapy for Olfactory Neuroblastoma

International Nuclear Information System (INIS)

Nishimura, Hideki; Ogino, Takashi; Kawashima, Mitsuhiko; Nihei, Keiji; Arahira, Satoko; Onozawa, Masakatsu; Katsuta, Shoichi; Nishio, Teiji

2007-01-01

Purpose: To analyze the feasibility and efficacy of proton-beam therapy (PBT) for olfactory neuroblastoma (ONB) as a definitive treatment, by reviewing our preliminary experience. Olfactory neuroblastoma is a rare disease, and a standard treatment strategy has not been established. Radiation therapy for ONB is challenging because of the proximity of ONBs to critical organs. Proton-beam therapy can provide better dose distribution compared with X-ray irradiation because of its physical characteristics, and is deemed to be a feasible treatment modality. Methods and Materials: A retrospective review was performed on 14 patients who underwent PBT for ONB as definitive treatment at the National Cancer Center Hospital East (Kashiwa, Chiba, Japan) from November 1999 to February 2005. A total dose of PBT was 65 cobalt Gray equivalents (Gy E ), with 2.5-Gy E once-daily fractionations. Results: The median follow-up period for surviving patients was 40 months. One patient died from disseminated disease. There were two persistent diseases, one of which was successfully salvaged with surgery. The 5-year overall survival rate was 93%, the 5-year local progression-free survival rate was 84%, and the 5-year relapse-free survival rate was 71%. Liquorrhea was observed in one patient with Kadish's stage C disease (widely destroying the skull base). Most patients experienced Grade 1 to 2 dermatitis in the acute phase. No other adverse events of Grade 3 or greater were observed according to the RTOG/EORTC acute and late morbidity scoring system. Conclusions: Our preliminary results of PBT for ONB achieved excellent local control and survival outcomes without serious adverse effects. Proton-beam therapy is considered a safe and effective modality that warrants further study

A study of V79 cell survival after for proton and carbon ion beams as represented by the parameters of Katz' track structure model

DEFF Research Database (Denmark)

Grzanka, Leszek; Waligórski, M. P. R.; Bassler, Niels

different sets of data obtained for the same cell line and different ions, measured at different laboratories, we have fitted model parameters to a set of carbon-irradiated V79 cells, published by Furusawa et al. (2), and to a set of proton-irradiated V79 cells, published by Wouters et al. (3), separately....... We found that values of model parameters best fitted to the carbon data of Furusawa et al. yielded predictions of V79 survival after proton irradiation which did not match the V79 proton data of Wouters et al. Fitting parameters to both sets combined did not improve the accuracy of model predictions...... carbon irradiation. 1. Katz, R., Track structure in radiobiology and in radiation detection. Nuclear Track Detection 2: 1-28 (1978). 2. Furusawa Y. et al. Inactivation of aerobic and hypoxic cells from three different cell lines by accelerated 3He-, 12C- and 20Ne beams. Radiat Res. 2012 Jan; 177...

Randomized Clinical Trial Comparing Proton Beam Radiation Therapy with Transarterial Chemoembolization for Hepatocellular Carcinoma: Results of an Interim Analysis

Energy Technology Data Exchange (ETDEWEB)

Bush, David A., E-mail: dbush@llu.edu [Department of Radiation Medicine, Loma Linda University Medical Center, Loma Linda, California (United States); Smith, Jason C. [Department of Diagnostic Radiology, Loma Linda University Medical Center, Loma Linda, California (United States); Slater, Jerry D. [Department of Radiation Medicine, Loma Linda University Medical Center, Loma Linda, California (United States); Volk, Michael L. [Transplantation Institute and Liver Center, Loma Linda University Medical Center, Loma Linda, California (United States); Reeves, Mark E. [VA Loma Linda Health Care System, Loma Linda, California (United States); Cheng, Jason [Transplantation Institute and Liver Center, Loma Linda University Medical Center, Loma Linda, California (United States); Grove, Roger [Department of Radiation Medicine, Loma Linda University Medical Center, Loma Linda, California (United States); Vera, Michael E. de [Transplantation Institute and Liver Center, Loma Linda University Medical Center, Loma Linda, California (United States)

2016-05-01

Purpose: To describe results of a planned interim analysis of a prospective, randomized clinical trial developed to compare treatment outcomes among patients with newly diagnosed hepatocellular carcinoma (HCC). Methods and Materials: Eligible subjects had either clinical or pathologic diagnosis of HCC and met either Milan or San Francisco transplant criteria. Patients were randomly assigned to transarterial chemoembolization (TACE) or to proton beam radiation therapy. Patients randomized to TACE received at least 1 TACE with additional TACE for persistent disease. Proton beam radiation therapy was delivered to all areas of gross disease to a total dose of 70.2 Gy in 15 daily fractions over 3 weeks. The primary endpoint was progression-free survival, with secondary endpoints of overall survival, local tumor control, and treatment-related toxicities as represented by posttreatment days of hospitalization. Results: At the time of this analysis 69 subjects were available for analysis. Of these, 36 were randomized to TACE and 33 to proton. Total days of hospitalization within 30 days of TACE/proton was 166 and 24 days, respectively (P<.001). Ten TACE and 12 proton patients underwent liver transplantation after treatment. Viable tumor identified in the explanted livers after TACE/proton averaged 2.4 and 0.9 cm, respectively. Pathologic complete response after TACE/proton was 10%/25% (P=.38). The 2-year overall survival for all patients was 59%, with no difference between treatment groups. Median survival time was 30 months (95% confidence interval 20.7-39.3 months). There was a trend toward improved 2-year local tumor control (88% vs 45%, P=.06) and progression-free survival (48% vs 31%, P=.06) favoring the proton beam treatment group. Conclusions: This interim analysis indicates similar overall survival rates for proton beam radiation therapy and TACE. There is a trend toward improved local tumor control and progression-free survival with proton beam. There are

The clinical case for proton beam therapy

International Nuclear Information System (INIS)

Foote, Robert L; Haddock, Michael G; Yan, Elizabeth; Laack, Nadia N; Arndt, Carola A S

2012-01-01

Over the past 20 years, several proton beam treatment programs have been implemented throughout the United States. Increasingly, the number of new programs under development is growing. Proton beam therapy has the potential for improving tumor control and survival through dose escalation. It also has potential for reducing harm to normal organs through dose reduction. However, proton beam therapy is more costly than conventional x-ray therapy. This increased cost may be offset by improved function, improved quality of life, and reduced costs related to treating the late effects of therapy. Clinical research opportunities are abundant to determine which patients will gain the most benefit from proton beam therapy. We review the clinical case for proton beam therapy. Proton beam therapy is a technically advanced and promising form of radiation therapy

How to survive within a yeast colony?: Change metabolism or cope with stress?

Czech Academy of Sciences Publication Activity Database

Čáp, M.; Váchová, Libuše; Palková, Z.

2010-01-01

Roč. 3, č. 2 (2010), s. 198-200 ISSN 1942-0889 R&D Projects: GA ČR GA204/08/0718; GA MŠk(CZ) LC531 Institutional research plan: CEZ:AV0Z50200510 Keywords : yeast colonies * stress defense and metabolic adaption * differentiation Subject RIV: EE - Microbiology, Virology

Protective, restorative, and therapeutic properties of recombinant colony-stimulating factors

International Nuclear Information System (INIS)

Talmadge, J.E.; Tribble, H.; Pennington, R.; Bowersox, O.; Schneider, M.A.; Castelli, P.; Black, P.L.; Abe, F.

1989-01-01

Pretreatment of mice with recombinant murine (rM) colony-stimulating factor-granulocyte-macrophage (CSF-gm) or recombinant human (rH) CSF-g provides partial protection from the lethal effects of ionizing radiation or the alkylating agent cyclophosphamide (CTX). In addition, these agents can significantly prolong survival if administered following lethal doses of irradiation or CTX. To induce protective activity, cytokines were injected 20 hours before lethal irradiation or CTX administration. To accelerate recovery from lethal irradiation, the cytokines must be administered shortly following irradiation, and the induction of maximal levels of activity is dependent on chronic administration. In contrast, because of their longer half-lives, accelerated recovery from alkylating agents requires a delay of at least 24 to 48 hours to allow complete clearance of CTX before administration of a CSF. Studies quantitating peripheral blood leukocytes and bone marrow cellularity as well as colony-forming units per culture (CFU-C) frequency and CFU-C per femur revealed a significant correlation between these parameters and the ability to survive lethal irradiation

Response of thyroid follicular cells to gamma irradiation compared to proton irradiation. I. Initial characterization of DNA damage, micronucleus formation, apoptosis, cell survival, and cell cycle phase redistribution

Science.gov (United States)

Green, L. M.; Murray, D. K.; Bant, A. M.; Kazarians, G.; Moyers, M. F.; Nelson, G. A.; Tran, D. T.

2001-01-01

The RBE of protons has been assumed to be equivalent to that of photons. The objective of this study was to determine whether radiation-induced DNA and chromosome damage, apoptosis, cell killing and cell cycling in organized epithelial cells was influenced by radiation quality. Thyroid-stimulating hormone-dependent Fischer rat thyroid cells, established as follicles, were exposed to gamma rays or proton beams delivered acutely over a range of physical doses. Gamma-irradiated cells were able to repair DNA damage relatively rapidly so that by 1 h postirradiation they had approximately 20% fewer exposed 3' ends than their counterparts that had been irradiated with proton beams. The persistence of free ends of DNA in the samples irradiated with the proton beam implies that either more initial breaks or a quantitatively different type of damage had occurred. These results were further supported by an increased frequency of chromosomal damage as measured by the presence of micronuclei. Proton-beam irradiation induced micronuclei at a rate of 2.4% per gray, which at 12 Gy translated to 40% more micronuclei than in comparable gamma-irradiated cultures. The higher rate of micronucleus formation and the presence of larger micronuclei in proton-irradiated cells was further evidence that a qualitatively more severe class of damage had been induced than was induced by gamma rays. Differences in the type of damage produced were detected in the apoptosis assay, wherein a significant lag in the induction of apoptosis occurred after gamma irradiation that did not occur with protons. The more immediate expression of apoptotic cells in the cultures irradiated with the proton beam suggests that the damage inflicted was more severe. Alternatively, the cell cycle checkpoint mechanisms required for recovery from such damage might not have been invoked. Differences based on radiation quality were also evident in the alpha components of cell survival curves (0.05 Gy(-1) for gamma rays, 0

Mating frequencies of honey bee queens (Apis mellifera L.) in a population of feral colonies in the Northeastern United States.

Science.gov (United States)

Tarpy, David R; Delaney, Deborah A; Seeley, Thomas D

2015-01-01

Across their introduced range in North America, populations of feral honey bee (Apis mellifera L.) colonies have supposedly declined in recent decades as a result of exotic parasites, most notably the ectoparasitic mite Varroa destructor. Nonetheless, recent studies have documented several wild populations of colonies that have persisted. The extreme polyandry of honey bee queens-and the increased intracolony genetic diversity it confers-has been attributed, in part, to improved disease resistance and may be a factor in the survival of these populations of feral colonies. We estimated the mating frequencies of queens in feral colonies in the Arnot Forest in New York State to determine if the level of polyandry of these queens is especially high and so might contribute to their survival success. We genotyped the worker offspring from 10 feral colonies in the Arnot Forest of upstate New York, as well as those from 20 managed colonies closest to this forest. We found no significant differences in mean mating frequency between the feral and managed queens, suggesting that queens in the remote, low-density population of colonies in the Arnot Forest are neither mate-limited nor adapted to mate at an especially high frequency. These findings support the hypothesis that the hyperpolyandry of honey bees has been shaped on an evolutionary timescale rather than on an ecological one.

Mating frequencies of honey bee queens (Apis mellifera L. in a population of feral colonies in the Northeastern United States.

Directory of Open Access Journals (Sweden)

David R Tarpy

Full Text Available Across their introduced range in North America, populations of feral honey bee (Apis mellifera L. colonies have supposedly declined in recent decades as a result of exotic parasites, most notably the ectoparasitic mite Varroa destructor. Nonetheless, recent studies have documented several wild populations of colonies that have persisted. The extreme polyandry of honey bee queens-and the increased intracolony genetic diversity it confers-has been attributed, in part, to improved disease resistance and may be a factor in the survival of these populations of feral colonies. We estimated the mating frequencies of queens in feral colonies in the Arnot Forest in New York State to determine if the level of polyandry of these queens is especially high and so might contribute to their survival success. We genotyped the worker offspring from 10 feral colonies in the Arnot Forest of upstate New York, as well as those from 20 managed colonies closest to this forest. We found no significant differences in mean mating frequency between the feral and managed queens, suggesting that queens in the remote, low-density population of colonies in the Arnot Forest are neither mate-limited nor adapted to mate at an especially high frequency. These findings support the hypothesis that the hyperpolyandry of honey bees has been shaped on an evolutionary timescale rather than on an ecological one.

Mating Frequencies of Honey Bee Queens (Apis mellifera L.) in a Population of Feral Colonies in the Northeastern United States

Science.gov (United States)

Tarpy, David R.; Delaney, Deborah A.; Seeley, Thomas D.

2015-01-01

Across their introduced range in North America, populations of feral honey bee (Apis mellifera L.) colonies have supposedly declined in recent decades as a result of exotic parasites, most notably the ectoparasitic mite Varroa destructor. Nonetheless, recent studies have documented several wild populations of colonies that have persisted. The extreme polyandry of honey bee queens—and the increased intracolony genetic diversity it confers—has been attributed, in part, to improved disease resistance and may be a factor in the survival of these populations of feral colonies. We estimated the mating frequencies of queens in feral colonies in the Arnot Forest in New York State to determine if the level of polyandry of these queens is especially high and so might contribute to their survival success. We genotyped the worker offspring from 10 feral colonies in the Arnot Forest of upstate New York, as well as those from 20 managed colonies closest to this forest. We found no significant differences in mean mating frequency between the feral and managed queens, suggesting that queens in the remote, low-density population of colonies in the Arnot Forest are neither mate-limited nor adapted to mate at an especially high frequency. These findings support the hypothesis that the hyperpolyandry of honey bees has been shaped on an evolutionary timescale rather than on an ecological one. PMID:25775410

Clinical equipoise: protons and the child with craniopharyngioma

International Nuclear Information System (INIS)

Conroy, Ruth; Owen, Catherine; Ahern, Verity; Gomes, Lavier; Buchsbaum, Jeremy

2015-01-01

Childhood craniopharyngioma is a complex condition to manage. Survival figures are high but the potential for long-term morbidity is great. There is much debate regarding the best management for these tumours with increasing interest in the use of proton beam therapy. We have therefore reviewed our radiotherapy (RT) practice at Westmead Hospital and the literature regarding the use of protons for these children. Three children have received fractionated stereotactic RT for craniopharyngioma at Westmead Hospital since 2007. Each RT plan was reviewed and additional organs at risk were contoured to enable comparison with published proton data. Planning target volume coverage was similar with all modalities: with the conformity index ranging from 0.70 to 0.78 in our patients compared with 0.50–0.84 in the published data. RT dose to temporal lobes, hippocampi and whole brain was also similar with protons and photons. Proton beam therapy may give lower dose to the Circle of Willis than stereotactic RT. Currently there is no clear evidence that proton beam therapy will improve survival or reduce morbidity for children with craniopharyngioma. However, proton therapy has the potential to reduce RT dose to the Circle of Willis, which may reduce the risk of future cerebrovascular complications. We propose that more resources should be allocated to ensuring these patients are managed by experienced multidisciplinary teams through the continuum from diagnosis to long-term follow-up.

Clinical equipoise: Protons and the child with craniopharyngioma.

Science.gov (United States)

Conroy, Ruth; Gomes, Lavier; Owen, Catherine; Buchsbaum, Jeffrey; Ahern, Verity

2015-06-01

Childhood craniopharyngioma is a complex condition to manage. Survival figures are high but the potential for long-term morbidity is great. There is much debate regarding the best management for these tumours with increasing interest in the use of proton beam therapy. We have therefore reviewed our radiotherapy (RT) practice at Westmead Hospital and the literature regarding the use of protons for these children. Three children have received fractionated stereotactic RT for craniopharyngioma at Westmead Hospital since 2007. Each RT plan was reviewed and additional organs at risk were contoured to enable comparison with published proton data. Planning target volume coverage was similar with all modalities: with the conformity index ranging from 0.70 to 0.78 in our patients compared with 0.50-0.84 in the published data. RT dose to temporal lobes, hippocampi and whole brain was also similar with protons and photons. Proton beam therapy may give lower dose to the Circle of Willis than stereotactic RT. Currently there is no clear evidence that proton beam therapy will improve survival or reduce morbidity for children with craniopharyngioma. However, proton therapy has the potential to reduce RT dose to the Circle of Willis, which may reduce the risk of future cerebrovascular complications. We propose that more resources should be allocated to ensuring these patients are managed by experienced multidisciplinary teams through the continuum from diagnosis to long-term follow-up. © 2014 The Royal Australian and New Zealand College of Radiologists.

The clinical case for proton beam therapy

Directory of Open Access Journals (Sweden)

Foote Robert L

2012-10-01

Full Text Available Abstract Over the past 20 years, several proton beam treatment programs have been implemented throughout the United States. Increasingly, the number of new programs under development is growing. Proton beam therapy has the potential for improving tumor control and survival through dose escalation. It also has potential for reducing harm to normal organs through dose reduction. However, proton beam therapy is more costly than conventional x-ray therapy. This increased cost may be offset by improved function, improved quality of life, and reduced costs related to treating the late effects of therapy. Clinical research opportunities are abundant to determine which patients will gain the most benefit from proton beam therapy. We review the clinical case for proton beam therapy. Summary sentence Proton beam therapy is a technically advanced and promising form of radiation therapy.

Proton channels and exchangers in cancer.

Science.gov (United States)

Spugnini, Enrico Pierluigi; Sonveaux, Pierre; Stock, Christian; Perez-Sayans, Mario; De Milito, Angelo; Avnet, Sofia; Garcìa, Abel Garcìa; Harguindey, Salvador; Fais, Stefano

2015-10-01

Although cancer is characterized by an intratumoral genetic heterogeneity, a totally deranged pH control is a common feature of most cancer histotypes. Major determinants of aberrant pH gradient in cancer are proton exchangers and transporters, including V-ATPase, Na+/H+ exchanger (NHE), monocarboxylate transporters (MCTs) and carbonic anhydrases (CAs). Thanks to the activity of these proton transporters and exchangers, cancer becomes isolated and/or protected not only from the body reaction against the growing tumor, but also from the vast majority of drugs that when protonated into the acidic tumor microenvironment do not enter into cancer cells. Proton transporters and exchangers represent a key feature tumor cells use to survive in the very hostile microenvironmental conditions that they create and maintain. Detoxifying mechanisms may thus represent both a key survival option and a selection outcome for cells that behave as unicellular microorganisms rather than belonging to an organ, compartment or body. It is, in fact, typical of malignant tumors that, after a clinically measurable yet transient initial response to a therapy, resistant tumor clones emerge and proliferate, thus bursting a more malignant behavior and rapid tumor progression. This review critically presents the background of a novel and efficient approach that aims to fight cancer through blocking or inhibiting well characterized proton exchangers and transporters active in human cancer cells. This article is part of a Special Issue entitled: Membrane channels and transporters in cancers. Copyright © 2014 Elsevier B.V. All rights reserved.

A prospective study of proton reirradiation for recurrent and secondary soft tissue sarcoma.

Science.gov (United States)

Guttmann, David M; Frick, Melissa A; Carmona, Ruben; Deville, Curtiland; Levin, William P; Berman, Abigail T; Chinniah, Chidambaram; Hahn, Stephen M; Plastaras, John P; Simone, Charles B

2017-08-01

Proton reirradiation for sarcoma has not been previously described. We hypothesized that this strategy would provide favorable toxicity and survival outcomes. Patients with soft tissue sarcoma in a previously-irradiated field were enrolled on a prospective trial of proton reirradiation. The primary endpoint was provider-reported acute toxicity. Secondary endpoints included late toxicities, local control, and overall survival. 23 patients underwent proton reirradiation. Median time between radiation courses was 40.7months (range 10-272). No grade 4-5 toxicities were observed. One patient (4%) experienced acute grade 3 dysphagia. Common grade 2 acute toxicities were fatigue (26%), anorexia (17%), and urinary incontinence (13%). There were two grade 3 late wound infections (10%) and one grade 3 late wound complication (5%). Grade 2 late complications included lymphedema (10%), fracture (5%), and fibrosis (5%). At a median follow-up of 36months, the 3-year cumulative incidence of local failure was 41% (95% CI [20-63%]). Median overall survival and progression-free survival were 44 and 29months, respectively. In extremity patients, amputation was spared in 7/10 (70%). Proton reirradiation of recurrent/secondary soft tissue sarcomas is well tolerated. While longer follow-up is needed, early survival outcomes in this high-risk population are encouraging. Copyright © 2017 Elsevier B.V. All rights reserved.

Bumblebee family lineage survival is enhanced in high-quality landscapes.

Science.gov (United States)

Carvell, Claire; Bourke, Andrew F G; Dreier, Stephanie; Freeman, Stephen N; Hulmes, Sarah; Jordan, William C; Redhead, John W; Sumner, Seirian; Wang, Jinliang; Heard, Matthew S

2017-03-23

Insect pollinators such as bumblebees (Bombus spp.) are in global decline. A major cause of this decline is habitat loss due to agricultural intensification. A range of global and national initiatives aimed at restoring pollinator habitats and populations have been developed. However, the success of these initiatives depends critically upon understanding how landscape change affects key population-level parameters, such as survival between lifecycle stages, in target species. This knowledge is lacking for bumblebees, because of the difficulty of systematically finding and monitoring colonies in the wild. We used a combination of habitat manipulation, land-use and habitat surveys, molecular genetics and demographic and spatial modelling to analyse between-year survival of family lineages in field populations of three bumblebee species. Here we show that the survival of family lineages from the summer worker to the spring queen stage in the following year increases significantly with the proportion of high-value foraging habitat, including spring floral resources, within 250-1,000 m of the natal colony. This provides evidence for a positive impact of habitat quality on survival and persistence between successive colony cycle stages in bumblebee populations. These findings also support the idea that conservation interventions that increase floral resources at a landscape scale and throughout the season have positive effects on wild pollinators in agricultural landscapes.

Understanding Long-Run African Growth : Colonial Institutions or Colonial Education?

NARCIS (Netherlands)

Bolt, J.; Bezemer, D.J.

2009-01-01

Long-term growth in developing countries has been explained in four frameworks: 'extractive colonial institutions' (Acemoglu et al., 2001), 'colonial legal origin' (La Porta et al., 2004), 'geography' (Gallup et al., 1998) and 'colonial human capital' (Glaeser et al., 2004). In this paper we test

Spatial variation in age structure among colonies of a marine snake: the influence of ectothermy.

Science.gov (United States)

Bonnet, Xavier; Brischoux, François; Pinaud, David; Michel, Catherine Louise; Clobert, Jean; Shine, Richard; Fauvel, Thomas

2015-07-01

Several tetrapod lineages that have evolved to exploit marine environments (e.g. seals, seabirds, sea kraits) continue to rely upon land for reproduction and, thus, form dense colonies on suitable islands. In birds and mammals (endotherms), the offspring cannot survive without their parents. Terrestrial colonies contain all age classes. In reptiles (ectotherms), this constraint is relaxed, because offspring are independent from birth. Hence, each age class has the potential to select sites with characteristics that favour them. Our studies of sea snakes (sea kraits) in the lagoon of New Caledonia reveal marked spatial heterogeneity in age structure among colonies. Sea krait colonies exhibit the endothermic 'seal-seabird' pattern (mixed-age classes within populations) only where the lagoon is narrow. Where the lagoon is wide, most snake colonies are comprised primarily of a single age cohort. Nurseries are located near the coast, adult colonies offshore and mixed colonies in-between. We suggest that ectothermy allows individuals to utilize habitats that are best suited to their own ecological requirements, a flexibility not available to endothermic marine taxa with obligate parental care. © 2015 The Authors. Journal of Animal Ecology © 2015 British Ecological Society.

Biofilm formation enhances Helicobacter pylori survivability in vegetables.

Science.gov (United States)

Ng, Chow Goon; Loke, Mun Fai; Goh, Khean Lee; Vadivelu, Jamuna; Ho, Bow

2017-04-01

To date, the exact route and mode of transmission of Helicobacter pylori remains elusive. The detection of H. pylori in food using molecular approaches has led us to postulate that the gastric pathogen may survive in the extragastric environment for an extended period. In this study, we show that H. pylori prolongs its survival by forming biofilm and micro-colonies on vegetables. The biofilm forming capability of H. pylori is both strain and vegetable dependent. H. pylori strains were classified into high and low biofilm formers based on their highest relative biofilm units (BU). High biofilm formers survived longer on vegetables compared to low biofilm formers. The bacteria survived better on cabbage compared to other vegetables tested. In addition, images captured on scanning electron and confocal laser scanning microscopes revealed that the bacteria were able to form biofilm and reside as micro-colonies on vegetable surfaces, strengthening the notion of possible survival of H. pylori on vegetables for an extended period of time. Taken together, the ability of H. pylori to form biofilm on vegetables (a common food source for human) potentially plays an important role in its survival, serving as a mode of transmission of H. pylori in the extragastric environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Metal contaminant accumulation in the hive: Consequences for whole-colony health and brood production in the honey bee (Apis mellifera L.).

Science.gov (United States)

Hladun, Kristen R; Di, Ning; Liu, Tong-Xian; Trumble, John T

2016-02-01

Metal pollution has been increasing rapidly over the past century, and at the same time, the human population has continued to rise and produce contaminants that may negatively impact pollinators. Honey bees (Apis mellifera L.) forage over large areas and can collect contaminants from the environment. The primary objective of the present study was to determine whether the metal contaminants cadmium (Cd), copper (Cu), lead (Pb), and selenium (Se) can have a detrimental effect on whole-colony health in the managed pollinator A. mellifera. The authors isolated small nucleus colonies under large cages and fed them an exclusive diet of sugar syrup and pollen patty spiked with Cd, Cu, Pb, and Se or a control (no additional metal). Treatment levels were based on concentrations in honey and pollen from contaminated hives around the world. They measured whole-colony health including wax, honey, and brood production; colony weight; brood survival; and metal accumulation in various life stages. Colonies treated with Cd or Cu contained more dead pupae within capped cells compared with control, and Se-treated colonies had lower total worker weights compared to control. Lead had a minimal effect on colony performance, although many members of the hive accumulated significant quantities of the metal. By examining the honey bee as a social organism through whole-colony assessments of toxicity, the authors found that the distribution of toxicants throughout the colony varied from metal to metal, some caste members were more susceptible to certain metals, and the colony's ability to grow over time may have been reduced in the presence of Se. Apiaries residing near metal-contaminated areas may be at risk and can suffer changes in colony dynamics and survival. © 2015 SETAC.

Mountain plover nest survival in relation to prairie dog and fire dynamics in shortgrass steppe

Science.gov (United States)

Augustine, David J.; Skagen, Susan K.

2014-01-01

Disturbed xeric grasslands with short, sparse vegetation provide breeding habitat for mountain plovers (Charadrius montanus) across the western Great Plains. Maintaining local disturbance regimes through prairie dog conservation and prescribed fire may contribute to the sustainability of recently declining mountain plover populations, but these management approaches can be controversial. We estimated habitat-specific mountain plover densities and nest survival rates on black-tailed prairie dog (Cynomys ludovicianus) colonies and burns in the shortgrass steppe of northeastern Colorado. Mountain plover densities were similar on prairie dog colonies (5.9 birds/km2; 95% CI = 4.7–7.4) and sites burned during the preceding dormant season (6.7 birds/km2; 95% CI = 4.6–9.6), whereas the 29-day nest survival rate was greater on prairie dog colonies (0.81 in 2011 and 0.39 in 2012) compared to the burned sites (0.64 in 2011 and 0.17 in 2012). Reduced nest survival in 2012 compared to 2011 was associated with higher maximum daily temperatures in 2012, consistent with a previous weather-based model of mountain plover nest survival in the southern Great Plains. Measurements of mountain plover density relative to time since disturbance showed that removal of prairie dog disturbance by sylvatic plague reduced mountain plover density by 70% relative to active prairie dog colonies after 1 year. Plover densities declined at a similar rate (by 78%) at burned sites between the first and second post-burn growing season. Results indicate that black-tailed prairie dog colonies are a particularly important nesting habitat for mountain plovers in the southern Great Plains. In addition, findings suggest that prescribed burning can be a valuable means to create nesting habitat in landscapes where other types of disturbances (such as prairie dog colonies) are limited in distribution and size. 

Survival of postfledging Forster's terns in relation to mercury exposure in San Francisco Bay

Science.gov (United States)

Ackerman, Joshua T.; Eagles-Smith, Collin A.; Takekawa, John Y.; Iverson, S.A.

2008-01-01

We examined factors influencing mercury concentrations in 90 fledgling Forster's terns (Sterna forsteri) and evaluated whether mercury influenced postfledging survival in San Francisco Bay, California. Mercury concentrations (??SE) in chicks 21-29 days old (just before fledging) were 0.33 ?? 0.01 ??g g-1 ww for blood and 6.44 ?? 0.28 ??g g -1 fw for breast feathers. Colony site had an overriding influence on fledgling contamination, however hatching date and age also affected blood, but not feather, mercury concentrations. Blood mercury concentrations decreased by 28% during the 50-day hatching period and increased with chick age by 30% during the last week prior to fledging. Using radio-telemetry, we calculated that cumulative survival during the 35-day postfledging time period was 0.81 ?? 0.09 (SE). Postfledging survival rates increased with size-adjusted mass, and cumulative survival probability was 61% lower for terns with the lowest, compared to the highest, observed masses. Conversely, survival was not influenced by blood mercury concentration, time since fledging, sex, or hatch date. Mercury concentrations in breast feathers of fledglings found dead at nesting colonies also were no different than those in live chicks. Our results indicate that colony site, hatching date, and age influenced mercury concentrations in fledgling Forster's terns, but that mercury did not influence postfledging survival. ?? 2008 Springer Science+Business Media, LLC.

The innate immune response may be important for surviving plague in wild Gunnison's prairie dogs

Science.gov (United States)

Busch, Joseph D.; Van Andel, Roger; Stone, Nathan E.; Cobble, Kacy R.; Nottingham, Roxanne; Lee, Judy; VerSteeg, Michael; Corcoran, Jeff; Cordova, Jennifer; Van Pelt, William E.; Shuey, Megan M.; Foster, Jeffrey T.; Schupp, James M.; Beckstrom-Sternberg, Stephen; Beckstrom-Sternberg, James; Keim, Paul; Smith, Susan; Rodriguez-Ramos, Julia; Williamson, Judy L.; Rocke, Tonie E.; Wagner, David M.

2013-01-01

Prairie dogs (Cynomys spp.) are highly susceptible to Yersinia pestis, with ≥99% mortality reported from multiple studies of plague epizootics. A colony of Gunnison's prairie dogs (Cynomys gunnisoni) in the Aubrey Valley (AV) of northern Arizona appears to have survived several regional epizootics of plague, whereas nearby colonies have been severely affected by Y. pestis. To examine potential mechanisms accounting for survival in the AV colony, we conducted a laboratory Y. pestis challenge experiment on 60 wild-caught prairie dogs from AV and from a nearby, large colony with frequent past outbreaks of plague, Espee (n = 30 per colony). Test animals were challenged subcutaneously with the fully virulent Y. pestis strain CO92 at three doses: 50, 5,000, and 50,000 colony-forming units (cfu); this range is lethal in black-tailed prairie dogs (Cynomys ludovicianus). Contrary to our expectations, only 40% of the animals died. Although mortality trended higher in the Espee colony (50%) compared with AV (30%), the differences among infectious doses were not statistically significant. Only 39% of the survivors developed moderate to high antibody levels to Y. pestis, indicating that mechanisms other than humoral immunity are important in resistance to plague. The ratio of neutrophils to lymphocytes was not correlated with plague survival in this study. However, several immune proteins with roles in innate immunity (VCAM-1, CXCL-1, and vWF) were upregulated during plague infection and warrant further inquiry into their role for protection against this disease. These results suggest plague resistance exists in wild populations of the Gunnison's prairie dog and provide important directions for future studies.

Biophysical characterization of a relativistic proton beam for image-guided radiosurgery.

Science.gov (United States)

Yu, Zhan; Vanstalle, Marie; La Tessa, Chiara; Jiang, Guo-Liang; Durante, Marco

2012-07-01

We measured the physical and radiobiological characteristics of 1 GeV protons for possible applications in stereotactic radiosurgery (image-guided plateau-proton radiosurgery). A proton beam was accelerated at 1 GeV at the Brookhaven National Laboratory (Upton, NY) and a target in polymethyl methacrylate (PMMA) was used. Clonogenic survival was measured after exposures to 1-10 Gy in three mammalian cell lines. Measurements and simulations demonstrate that the lateral scattering of the beam is very small. The lateral dose profile was measured with or without the 20-cm plastic target, showing no significant differences up to 2 cm from the axis A large number of secondary swift protons are produced in the target and this leads to an increase of approximately 40% in the measured dose on the beam axis at 20 cm depth. The relative biological effectiveness at 10% survival level ranged between 1.0 and 1.2 on the beam axis, and was slightly higher off-axis. The very low lateral scattering of relativistic protons and the possibility of using online proton radiography during the treatment make them attractive for image-guided plateau (non-Bragg peak) stereotactic radiosurgery.

Biophysical characterization of a relativistic proton beam for image-guided radiosurgery

International Nuclear Information System (INIS)

Yu, Z.; Vanstalle, M.; La Tessa, C.; Durante, M.; Jiang Guoliang

2012-01-01

We measured the physical and radiobiological characteristics of 1 GeV protons for possible applications in stereotactic radiosurgery (image-guided plateau-proton radiosurgery). A proton beam was accelerated at 1 GeV at the Brookhaven National Laboratory (Upton, NY) and a target in polymethyl methacrylate (PMMA) was used. Clonogenic survival was measured after exposures to 1-10 Gy in three mammalian cell lines. Measurements and simulations demonstrate that the lateral scattering of the beam is very small. The lateral dose profile was measured with or without the 20-cm plastic target, showing no significant differences up to 2 cm from the axis A large number of secondary swift protons are produced in the target and this leads to an increase of approximately 40% in the measured dose on the beam axis at 20 cm depth. The relative biological effectiveness at 10% survival level ranged between 1.0 and 1.2 on the beam axis, and was slightly higher off-axis. The very low lateral scattering of relativistic protons and the possibility of using online proton radiography during the treatment make them attractive for image-guided plateau (non-Bragg peak) stereotactic radiosurgery. (author)

On colonial grounds

NARCIS (Netherlands)

Dommelen, Peter Alexander René van

1998-01-01

As a study of the colonial situations of first millennium BC Sardinia, this book is as much an investigation into colonialism as a sociological category, as it explores the specific historical conditions of a particular region. Taking a fresh look at colonialism in Mediterranean archaeology from a

Microaerobic growth and anaerobic survival of Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium scrofulaceum.

Science.gov (United States)

Lewis, Amy Herndon; Falkinham, Joseph O

2015-03-01

Representative strains of Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium scrofulaceum (MAIS) grew at equal rates in laboratory medium at 21% (air) and 12% oxygen. Growth in 6% oxygen proceeded at a 1.4-1.8-fold lower rate. Colony formation was the same at 21% (air) and 6% oxygen. The MAIS strains survived rapid shifts from aerobic to anaerobic conditions as measured by two experimental approaches (Falkinham (1996) [1]). MAIS cells grown aerobically to log phase in broth were diluted, spread on agar medium, and incubated anaerobically for up to 20 days at 37°C. Although no colonies formed anaerobically, upon transfer to aerobic conditions, greater than 25% of the colony forming units (CFU) survived after 20 days of anaerobic incubation (Prince et al. (1989) [2]). MAIS cells grown in broth aerobically to log phase were sealed and vigorous agitation led to oxygen depletion (Wayne model). After 12 days anaerobic incubation, M. avium and M. scrofulaceum survival were high (>50%), while M. intracellulare survival was lower (22%). M. avium cells shifted to anaerobiosis in broth had increased levels of glycine dehydrogenase and isocitrate lyase. Growth of MAIS strains at low oxygen levels and their survival following a rapid shift to anaerobiosis is consistent with their presence in environments with fluctuating oxygen levels. Copyright © 2015 Asian African Society for Mycobacteriology. Published by Elsevier Ltd. All rights reserved.

Microaerobic growth and anaerobic survival of Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium scrofulaceum

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Amy Herndon Lewis

2015-01-01

Full Text Available Representative strains of Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium scrofulaceum (MAIS grew at equal rates in laboratory medium at 21% (air and 12% oxygen. Growth in 6% oxygen proceeded at a 1.4–1.8-fold lower rate. Colony formation was the same at 21% (air and 6% oxygen. The MAIS strains survived rapid shifts from aerobic to anaerobic conditions as measured by two experimental approaches (Falkinham (1996 [1]. MAIS cells grown aerobically to log phase in broth were diluted, spread on agar medium, and incubated anaerobically for up to 20 days at 37 °C. Although no colonies formed anaerobically, upon transfer to aerobic conditions, greater than 25% of the colony forming units (CFU survived after 20 days of anaerobic incubation (Prince et al. (1989 [2]. MAIS cells grown in broth aerobically to log phase were sealed and vigorous agitation led to oxygen depletion (Wayne model. After 12 days anaerobic incubation, M. avium and M. scrofulaceum survival were high (>50%, while M. intracellulare survival was lower (22%. M. avium cells shifted to anaerobiosis in broth had increased levels of glycine dehydrogenase and isocitrate lyase. Growth of MAIS strains at low oxygen levels and their survival following a rapid shift to anaerobiosis is consistent with their presence in environments with fluctuating oxygen levels.

Evaluation of the Inhalation Toxicology Research Institute beagle dog closed breeding colony: a progress report

International Nuclear Information System (INIS)

Lustgarten, C.S.; Hobbs, C.H.; Muggenburg, B.A.; Benjamin, S.A.; Slauson, D.O.; Hahn, F.F.

1974-01-01

Since early 1968, a closed breeding colony has been in operation at the Inhalation Toxicology Research Institute to produce experimental dogs for inhalation toxicology studies and to replace colony breeding stock for producing dogs with a stable gene pool. From March 1, 1968 through July 15, 1974, 123 bitches were bred 613 times, resulting in 540 litters and 2809 puppies: a conception rate for this period of 88.9 percent. An average of 3.74 pups survived to one year of age. (U.S.)

Particle production and survival in muon acceleration

Energy Technology Data Exchange (ETDEWEB)

Noble, R.J.

1992-06-01

Because of the relative immunity of muons to synchrotron radiation, the idea of using them instead of electrons as probes in high-energy physics experiments has existed for some time, but applications were limited by the short muon lifetime. The production and survival of an adequate supply of low-emittance muons will determine the available luminosity in a high-energy physics collider. In this paper the production of pions by protons, their decay to muons and the survival of muons during acceleration are studied. Based on a combination of the various efficiencies, the number of protons needed at the pion source for every muon required in the final high-energy collider is estimated.

Ireland – a test case of Post-colonialism / Post colonialism

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Brenda Murray

2006-05-01

Full Text Available Contextualisation This review attempts to set the stage for post-colonial theorising, in the light of alternative representations of ‘whiteness’, on issues of gender, race and language within the discourse of equality. In this paper Ireland and the Irish provide a backdrop against which the nature and impact of colonialism on the colonised and the coloniser are explored. Many challenging questions emerge about the ideological basis of post colonial theory, not least when traditional paradigms of racism, as conveyed by the black / white dichotomy, are examined: Ireland presents a context, it is argued, where subjugation is of white on white. Linked to this is the language of the coloniser, a powerful hegemonic force which, in some situations, has been nurtured by the colonised and later developed into a text which is unique, producing a new literature which, it is asserted, truly invokes the ‘post colonial’. Abstract: Post-colonialism – essentially a critique of colonialism, is characterised by a process of disengagement from the colonial epoch and has taken many forms. In this article a set of phenomena are examined that have become inscribed in the cultures of the colonised with a view to identifying alternative cultural origins and dispositions recovered in this post-colonial era. Ireland and the Irish provide the background context of this exploration into perspectives generated by the peripheral or post-colonial nations. Globalisation, too, has had a role to play in the increasing de-territorialisation of communities as a result of cross-frontier mobility, increased intra-community mobility and new communication technologies. A critical reflection on the process of disengagement leads the author to conclude that we must come to recognise new cultural forms which are accepting of a heterogeneous and inclusive society: one which is not characterised by difference.

Rethinking the Combination of Proton Exchanger Inhibitors in Cancer Therapy.

Science.gov (United States)

Iessi, Elisabetta; Logozzi, Mariantonia; Mizzoni, Davide; Di Raimo, Rossella; Supuran, Claudiu T; Fais, Stefano

2017-12-23

Microenvironmental acidity is becoming a key target for the new age of cancer treatment. In fact, while cancer is characterized by genetic heterogeneity, extracellular acidity is a common phenotype of almost all cancers. To survive and proliferate under acidic conditions, tumor cells up-regulate proton exchangers and transporters (mainly V-ATPase, Na⁺/H⁺ exchanger (NHE), monocarboxylate transporters (MCTs), and carbonic anhydrases (CAs)), that actively extrude excess protons, avoiding intracellular accumulation of toxic molecules, thus becoming a sort of survival option with many similarities compared with unicellular microorganisms. These systems are also involved in the unresponsiveness or resistance to chemotherapy, leading to the protection of cancer cells from the vast majority of drugs, that when protonated in the acidic tumor microenvironment, do not enter into cancer cells. Indeed, as usually occurs in the progression versus malignancy, resistant tumor clones emerge and proliferate, following a transient initial response to a therapy, thus giving rise to more malignant behavior and rapid tumor progression. Recent studies are supporting the use of a cocktail of proton exchanger inhibitors as a new strategy against cancer.

A branching process model for the analysis of abortive colony size distributions in carbon ion-irradiated normal human fibroblasts

International Nuclear Information System (INIS)

Sakashita, Tetsuya; Kobayashi, Yasuhiko; Hamada, Nobuyuki; Kawaguchi, Isao; Hara, Takamitsu; Saito, Kimiaki

2014-01-01

A single cell can form a colony, and ionizing irradiation has long been known to reduce such a cellular clonogenic potential. Analysis of abortive colonies unable to continue to grow should provide important information on the reproductive cell death (RCD) following irradiation. Our previous analysis with a branching process model showed that the RCD in normal human fibroblasts can persist over 16 generations following irradiation with low linear energy transfer (LET) γ-rays. Here we further set out to evaluate the RCD persistency in abortive colonies arising from normal human fibroblasts exposed to high-LET carbon ions (18.3 MeV/u, 108 keV/μm). We found that the abortive colony size distribution determined by biological experiments follows a linear relationship on the log–log plot, and that the Monte Carlo simulation using the RCD probability estimated from such a linear relationship well simulates the experimentally determined surviving fraction and the relative biological effectiveness (RBE). We identified the short-term phase and long-term phase for the persistent RCD following carbon-ion irradiation, which were similar to those previously identified following γ-irradiation. Taken together, our results suggest that subsequent secondary or tertiary colony formation would be invaluable for understanding the long-lasting RCD. All together, our framework for analysis with a branching process model and a colony formation assay is applicable to determination of cellular responses to low- and high-LET radiation, and suggests that the long-lasting RCD is a pivotal determinant of the surviving fraction and the RBE. (author)

Apparent survival of adult Leach's Storm-petrels (Oceanodroma leucorhoa breeding on Bon Portage Island, Nova Scotia

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Danielle T. Fife

2015-12-01

Full Text Available Populations of Leach's Storm-petrel (Oceanodroma leucorhoa; hereafter storm-petrel, one of the most widespread procellariiform seabirds in the world, appear to be declining in many parts of their breeding range. As part of a regional effort to assess status of storm-petrel colonies in eastern North America, we estimated apparent survival and recapture probabilities from 2009 to 2014 for adults on Bon Portage Island (43° 28' N, 65° 44' W, located off the southwestern coast of Nova Scotia, Canada. Mean annual survival estimated for this colony was low (0.78 ± 0.04 compared with other procellariiforms, e.g., > 0.90 for many albatrosses and petrels. Storm-petrels that were fitted with very high frequency (VHF radio tags had an average of 0.11 ± 0.05 (95% confidence interval [CI] = 0.01 to 0.21 higher survival probabilities than those that were not, possibly because VHF tags were attached to known, established breeders. There was weak evidence that survival was reduced by an average of 0.07 ± 0.04 for storm-petrels in study plots that were occupied by Herring Gulls (Larus argentatus and their chicks; however, this result was not statistically significant (95% CI: -0.15 to 0.02. Low adult survival is an early indication that this important colony may be under stress. However, further work is needed to determine if the colony is indeed declining and, if so, to determine the cause(s of the decline so that they may be addressed.

WE-G-BRE-07: Proton Therapy Enhanced by Tumor-Targeting Gold Nanoparticles: A Pilot in Vivo Experiment at The Proton Therapy Center at MD Anderson Cancer Center

Energy Technology Data Exchange (ETDEWEB)

Wolfe, T; Grant, J; Wolfe, A; Gillin, M; Krishnan, S [MD Anderson Cancer Ctr., Houston, TX (United States)

2014-06-15

Purpose: Assess tumor-growth delay and survival in a mouse model of prostate cancer treated with tumor-targeting gold nanoparticles (AuNPs) and proton therapy. Methods: We first examined the accumulation of targeting nanoparticles within prostate tumors by imaging AuNPs with ultrasound-guided photoacoustics at 24h after the intravenous administration of goserelin-conjugated AuNPs (gAuNP) in three mice. Nanoparticles were also imaged at the cellular level with TEM in PC3 cells incubated with gAuNP for 24h. Pegylated AuNPs (pAuNP) were also imaged in vivo and in vitro for comparison. PC3 cells were then implanted subcutaneously in nude mice; 51mice with 8–10mm tumors were included. AuNPs were injected intravenously at 0.2%w/w final gold concentration 24h before irradiation. A special jig was designed to facilitate tumor irradiation perpendicular to the proton beam. Proton energy was set to 180MeV, the radiation field was 18×18cm{sup 2}, and 9cm or 13.5cm thick solid-water compensators were used to position the tumors at either the beam entrance (BE) or the SOBP. Physical doses of 5Gy were delivered to all tumors on a patient beam line at MD Anderson's Proton Therapy Center. Results: The photoacoustic experiment reveled that our nanoparticles leak from the tumor-feeding vasculature and accumulate within the tumor volume over time. Additionally, TEM images showed gAuNP are internalized in cancer cells, accumulating within the cytoplasm, whereas pAuNP are not. Tumor-growth was delayed by 11 or 32days in mice receiving gAuNP irradiated at the BE or the SOBP, relative to proton radiation alone. Survival curves (ongoing experiment) reveal that gAuNPs improved survival by 36% or 74% for tumors irradiated at the BE or SOBP. Conclusion: These important, albeit preliminary, in vivo findings reveal nanoparticles to be potent sensitizers to proton therapy. Further, conjugation of AuNPs to tumor-specific antigens that promote enhanced cellular internalization improved

Resilience of honeybee colonies via common stomach: A model of self-regulation of foraging.

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Thomas Schmickl

Full Text Available We propose a new regulation mechanism based on the idea of the "common stomach" to explain several aspects of the resilience and homeostatic regulation of honeybee colonies. This mechanism exploits shared pools of substances (pollen, nectar, workers, brood that modulate recruitment, abandonment and allocation patterns at the colony-level and enable bees to perform several survival strategies to cope with difficult circumstances: Lack of proteins leads to reduced feeding of young brood, to early capping of old brood and to regaining of already spent proteins through brood cannibalism. We modeled this system by linear interaction terms and mass-action law. To test the predictive power of the model of this regulatory mechanism we compared our model predictions to experimental data of several studies. These comparisons show that the proposed regulation mechanism can explain a variety of colony level behaviors. Detailed analysis of the model revealed that these mechanisms could explain the resilience, stability and self-regulation observed in honeybee colonies. We found that manipulation of material flow and applying sudden perturbations to colony stocks are quickly compensated by a resulting counter-acting shift in task selection. Selective analysis of feedback loops allowed us to discriminate the importance of different feedback loops in self-regulation of honeybee colonies. We stress that a network of simple proximate mechanisms can explain significant colony-level abilities that can also be seen as ultimate reasoning of the evolutionary trajectory of honeybees.

Cost-effectiveness of histamine receptor-2 antagonist versus proton pump inhibitor for stress ulcer prophylaxis in critically ill patients*.

Science.gov (United States)

MacLaren, Robert; Campbell, Jon

2014-04-01

To examine the cost-effectiveness of using histamine receptor-2 antagonist or proton pump inhibitor for stress ulcer prophylaxis. Decision analysis model examining costs and effectiveness of using histamine receptor-2 antagonist or proton pump inhibitor for stress ulcer prophylaxis. Costs were expressed in 2012 U.S. dollars from the perspective of the institution and included drug regimens and the following outcomes: clinically significant stress-related mucosal bleed, ventilator-associated pneumonia, and Clostridium difficile infection. Effectiveness was the mortality risk associated with these outcomes and represented by survival. Costs, occurrence rates, and mortality probabilities were extracted from published data. A simulation model. A mixed adult ICU population. Histamine receptor-2 antagonist or proton pump inhibitor for 9 days of stress ulcer prophylaxis therapy. Output variables were expected costs, expected survival rates, incremental cost, and incremental survival rate. Univariate sensitivity analyses were conducted to determine the drivers of incremental cost and incremental survival. Probabilistic sensitivity analysis was conducted using second-order Monte Carlo simulation. For the base case analysis, the expected cost of providing stress ulcer prophylaxis was $6,707 with histamine receptor-2 antagonist and $7,802 with proton pump inhibitor, resulting in a cost saving of $1,095 with histamine receptor-2 antagonist. The associated mortality probabilities were 3.819% and 3.825%, respectively, resulting in an absolute survival benefit of 0.006% with histamine receptor-2 antagonist. The primary drivers of incremental cost and survival were the assumptions surrounding ventilator-associated pneumonia and bleed. The probabilities that histamine receptor-2 antagonist was less costly and provided favorable survival were 89.4% and 55.7%, respectively. A secondary analysis assuming equal rates of C. difficile infection showed a cost saving of $908 with histamine

Rapidity gap survival in enhanced Pomeron scheme

Energy Technology Data Exchange (ETDEWEB)

Ostapchenko, Sergey [Frankfurt Institute for Advanced Studies, Frankfurt am Main (Germany); Moscow State University, D.V. Skobeltsyn Institute of Nuclear Physics, Moscow (Russian Federation); Bleicher, Marcus [Frankfurt Institute for Advanced Studies, Frankfurt am Main (Germany); Goethe-Universitat, Institute for Theoretical Physics, Frankfurt am Main (Germany)

2018-01-15

We apply the phenomenological Reggeon field theory framework to investigate rapidity gap survival (RGS) probability for diffractive dijet production in proton-proton collisions. In particular, we study in some detail rapidity gap suppression due to elastic rescatterings of intermediate partons in the underlying parton cascades, described by enhanced (Pomeron-Pomeron interaction) diagrams. We demonstrate that such contributions play a subdominant role, compared to the usual, so-called ''eikonal'', rapidity gap suppression due to elastic rescatterings of constituent partons of the colliding protons. On the other hand, the overall RGS factor proves to be sensitive to color fluctuations in the proton. Hence, experimental data on diffractive dijet production can be used to constrain the respective model approaches. (orig.)

Surviving bacterial sibling rivalry: inducible and reversible phenotypic switching in Paenibacillus dendritiformis.

Science.gov (United States)

Be'er, Avraham; Florin, E-L; Fisher, Carolyn R; Swinney, Harry L; Payne, Shelley M

2011-01-01

Natural habitats vary in available nutrients and room for bacteria to grow, but successful colonization can lead to overcrowding and stress. Here we show that competing sibling colonies of Paenibacillus dendritiformis bacteria survive overcrowding by switching between two distinct vegetative phenotypes, motile rods and immotile cocci. Growing colonies of the rod-shaped bacteria produce a toxic protein, Slf, which kills cells of encroaching sibling colonies. However, sublethal concentrations of Slf induce some of the rods to switch to Slf-resistant cocci, which have distinct metabolic and resistance profiles, including resistance to cell wall antibiotics. Unlike dormant spores of P. dendritiformis, the cocci replicate. If cocci encounter conditions that favor rods, they secrete a signaling molecule that induces a switch to rods. Thus, in contrast to persister cells, P. dendritiformis bacteria adapt to changing environmental conditions by inducible and reversible phenotypic switching. In favorable environments, species may face space and nutrient limits due to overcrowding. Bacteria provide an excellent model for analyzing principles underlying overcrowding and regulation of density in nature, since their population dynamics can be easily and accurately assessed under controlled conditions. We describe a newly discovered mechanism for survival of a bacterial population during overcrowding. When competing with sibling colonies, Paenibacillus dendritiformis produces a lethal protein (Slf) that kills cells at the interface of encroaching colonies. Slf also induces a small proportion of the cells to switch from motile, rod-shaped cells to nonmotile, Slf-resistant, vegetative cocci. When crowding is reduced and nutrients are no longer limiting, the bacteria produce a signal that induces cocci to switch back to motile rods, allowing the population to spread. Genes encoding components of this phenotypic switching pathway are widespread among bacterial species, suggesting

Factors influencing survival duration and choice of virgin queens in the stingless bee Melipona quadrifasciata

Science.gov (United States)

Kärcher, Martin H.; Menezes, Cristiano; Alves, Denise A.; Beveridge, Oliver S.; Imperatriz-Fonseca, Vera-Lucia; Ratnieks, Francis L. W.

2013-06-01

In Melipona quadrifasciata, about 10 % of the females develop into queens, almost all of which are killed. Occasionally, a new queen replaces or supersedes the mother queen or heads a new colony. We investigated virgin queen fate in queenright and queenless colonies to determine the effects of queen behaviour, body mass, nestmate or non-nestmate status, queenright or queenless colony status, and, when queenless, the effect of the time a colony had been queenless, on survival duration and acceptance. None of 220 virgin queens observed in four observation hives ever attacked another virgin queen nor did any of 88 virgin queens introduced into queenright colonies ever attack the resident queen. A new queen was only accepted in a queenless colony. Factors increasing survival duration and acceptance of virgin queens were to emerge from its cell at 2 h of queenlessness, to hide, and to avoid fights with workers. In this way, a virgin queen was more likely to be available when a colony chooses a new queen, 24-48 h after resident queen removal. Running, walking or resting, antennating or trophallaxis, played little or no role, as did the factors body mass or nestmate. "Queen choice" took about 2 h during which time other virgin queens were still being killed by workers. During this agitated process, the bees congregated around the new queen. She inflated her abdomen and some of the workers deposited a substance on internal nest surfaces including the glass lid of the observation hive.

Influence of feeding bee colonies on colony strenght and honey authenticity

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Andreja KANDOLF BOROVŠAK

2015-12-01

Full Text Available For the natural development of bee colonies, there is the need for appropriate nutrition. Lack of natural honey flow must be supplemented by feeding bee colonies with sugar syrups or candy paste. This supplementary feeding encourages brood breeding and forage activity, whereby stronger colonies collect more honey. Sugar syrups can cause honey adulteration, which is more frequent with the reversing of the brood combs with the bee food, with the combs moved from the brood chamber to the upper chamber. Authentication of honey from the standpoint of the presence of sugar syrup is very complex, because there is no single method by which honey adulteration can be reliably confirmed. Feeding the colonies in spring should result in stronger colonies and hence the collection of more honey in the brood chambers. The objective of the present study was to determine whether this has effects also on honey authenticity, and to discover a simple method for detection of honey adulteration. The colonies were fed with candy paste that had added yeast and blue dye, to provide markers for detection of honey adulteration. The strength of the colonies and quantity of honey in the brood chambers were monitored. The results of the analysis of stable isotope and activity of foreign enzymes were compared with the results of yeast quantity and colour of the honey (absorbance, L*, a*, b* parameters. Detection of yeast in the honey samples and presence of colour as a consequence of added dye appear to be appropriate methods to follow honey adulteration, and further studies are ongoing.

Increased tolerance and resistance to virus infections: a possible factor in the survival of Varroa destructor-resistant honey bees (Apis mellifera.

Directory of Open Access Journals (Sweden)

Barbara Locke

Full Text Available The honey bee ectoparasitic mite, Varroa destructor, has a world-wide distribution and inflicts more damage than all other known apicultural diseases. However, Varroa-induced colony mortality is more accurately a result of secondary virus infections vectored by the mite. This means that honey bee resistance to Varroa may include resistance or tolerance to virus infections. The aim of this study was to see if this is the case for a unique population of mite-resistant (MR European honey bees on the island of Gotland, Sweden. This population has survived uncontrolled mite infestation for over a decade, developing specific mite-related resistance traits to do so. Using RT-qPCR techniques, we monitored late season virus infections, Varroa mite infestation and honey bee colony population dynamics in the Gotland MR population and compared this to mite-susceptible (MS colonies in a close by apiary. From summer to autumn the deformed wing virus (DWV titres increased similarly between the MR and MS populations, while the black queen cell virus (BQCV and sacbrood virus (SBV titres decreased substantially in the MR population compared to the MS population by several orders of magnitude. The MR colonies all survived the following winter with high mite infestation, high DWV infection, small colony size and low proportions of autumn brood, while the MS colonies all perished. Possible explanations for these changes in virus titres and their relevance to Varroa resistance and colony winter survival are discussed.

Preliminary results of proton therapy in choroidal melanoma at the centre de proton therapy d'Orsay (C.P.O.): 464 initial cases

International Nuclear Information System (INIS)

Desjardins, L.; Levy, C.; D'hermies, F.; Frau, E.; Schlienger, P.; Habrand, J.L.; Mammar, H.; Schwartz, L.; Mazal, A.; Delacroix, S.; Nauraye, C.; Ferrand, R.; Asselain, B.

1997-01-01

Retrospective analysis of the treatment of choroidal melanoma with proton-therapy at the Centre de protontherapie d'Orsay, France. Between September 1991 and September 1995, 612 patients presenting with choroidal melanoma were treated by proton-therapy in Orsay. Following initial management of the first 464 patients, results were analyzed, as were results after a 1-year follow up for 305 patients, a 2-year follow-up for 169 patients, and a 3-year follow-up for 59 patients. Univariate analysis showed that the actuarial local recurrence rate was 5 %, the 3-year survival rate 88 %, and the overall metastatic rate 5%. The initial tumor volume was the most significant predictive factor for visual results and metastases. Multivariate analysis revealed that visual results were significantly related to the initial tumor volume, initial retinal detachment, and total dose delivered to the optic nerve and macula. Proton-therapy of choroidal melanoma allows in most cases conservation of the eye without modification of survival. Visual results mainly depend on the site and size of the tumor. (author)

Winter fidelity and apparent survival of lesser snow goose populations in the Pacific flyway

Science.gov (United States)

Williams, C.K.; Samuel, M.D.; Baranyuk, Vasily V.; Cooch, E.G.; Kraege, Donald K.

2008-01-01

The Beringia region of the Arctic contains 2 colonies of lesser snow geese (Chen caerulescens caerulescens) breeding on Wrangel Island, Russia, and Banks Island, Canada, and wintering in North America. The Wrangel Island population is composed of 2 subpopulations from a sympatric breeding colony but separate wintering areas, whereas the Banks Island population shares a sympatric wintering area in California, USA, with one of the Wrangel Island subpopulations. The Wrangel Island colony represents the last major snow goose population in Russia and has fluctuated considerably since 1970, whereas the Banks Island population has more than doubled. The reasons for these changes are unclear, but hypotheses include independent population demographics (survival and recruitment) and immigration and emigration among breeding or wintering populations. These demographic and movement patterns have important ecological and management implications for understanding goose population structure, harvest of admixed populations, and gene flow among populations with separate breeding or wintering areas. From 1993 to 1996, we neckbanded molting birds at their breeding colonies and resighted birds on the wintering grounds. We used multistate mark-recapture models to evaluate apparent survival rates, resighting rates, winter fidelity, and potential exchange among these populations. We also compared the utility of face stain in Wrangel Island breeding geese as a predictor of their wintering area. Our results showed similar apparent survival rates between subpopulations of Wrangel Island snow geese and lower apparent survival, but higher emigration, for the Banks Island birds. Males had lower apparent survival than females, most likely due to differences in neckband loss. Transition between wintering areas was low (exchange between the Banks and northern Wrangel Island populations. Face staining was an unreliable indicator of wintering area. Our findings suggest that northern and southern

Enzootic plague reduces black-footed ferret (Mustela nigripes) survival in Montana

Science.gov (United States)

Matchett, Marc R.; Biggins, Dean E.; Carlson, Valerie; Powell, Bradford; Rocke, Tonie E.

2010-01-01

Black-footed ferrets (Mustela nigripes) require extensive prairie dog colonies (Cynomys spp.) to provide habitat and prey. Epizootic plague kills both prairie dogs and ferrets and is a major factor limiting recovery of the highly endangered ferret. In addition to epizootics, we hypothesized that enzootic plague, that is, presence of disease-causing Yersinia pestis without any noticeable prairie dog die off, may also affect ferret survival. We reduced risk of plague on portions of two ferret reintroduction areas by conducting flea control for 3 years. Beginning in 2004, about half of the ferrets residing on dusted and nondusted colonies were vaccinated against plague with an experimental vaccine (F1-V fusion protein). We evaluated 6-month reencounter rates (percentage of animals observed at the end of an interval that were known alive at the beginning of the interval), an index to survival, for ferrets in four treatment groups involving all combinations of vaccination and flea control. For captive-reared ferrets (115 individuals observed across 156 time intervals), reencounter rates were higher for vaccinates (0.44) than for nonvaccinates (0.23, p = 0.044) on colonies without flea control, but vaccination had no detectable effect on colonies with flea control (vaccinates = 0.41, nonvaccinates = 0.42, p = 0.754). Flea control resulted in higher reencounter rates for nonvaccinates (p = 0.026), but not for vaccinates (p = 0.508). The enhancement of survival due to vaccination or flea control supports the hypothesis that enzootic plague reduces ferret survival, even when there was no noticeable decline in prairie dog abundance. The collective effects of vaccination and flea control compel a conclusion that fleas are required for maintenance, and probably transmission, of plague at enzootic levels. Other studies have demonstrated similar effects of flea control on several species of prairie dogs and, when combined with this study, suggest

Review Essay A history of colonialism through post-colonial lenses ...

African Journals Online (AJOL)

Review Essay A history of colonialism through post-colonial lenses: reading Mahmood Mamdani's citizen and subject. Sanya Osha. Abstract. No Abstract. The Nigerian Journal of Economic History Vol. 2, 1999: 155-161. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

Proton Radiotherapy for Parameningeal Rhabdomyosarcoma: Clinical Outcomes and Late Effects

Energy Technology Data Exchange (ETDEWEB)

Childs, Stephanie K. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Kozak, Kevin R. [Department of Radiation Oncology, University of Wisconsin Cancer Center Johnson Creek, Madison, WI (United States); Friedmann, Alison M. [Department of Pediatric Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Yeap, Beow Y. [Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Adams, Judith; MacDonald, Shannon M.; Liebsch, Norbert J.; Tarbell, Nancy J. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Yock, Torunn I., E-mail: tyock@partners.org [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States)

2012-02-01

Purpose: To report the clinical outcome and late side effect profile of proton radiotherapy in the treatment of children with parameningeal rhabdomyosarcoma (PM-RMS). Methods and Materials: Seventeen consecutive children with PM-RMS were treated with proton radiotherapy at Massachusetts General Hospital between 1996 and 2005. We reviewed the medical records of all patients and asked referring physicians to report specific side effects of interest. Results: Median patient age at diagnosis was 3.4 years (range, 0.4-17.6). Embryonal (n = 11), alveolar (n = 4), and undifferentiated (n = 2) histologies were represented. Ten patients (59%) had intracranial extension. Median prescribed dose was 50.4 cobalt gray equivalents (GyRBE) (range, 50.4-56.0 GyRBE) delivered in 1.8-2.0-GyRBE daily fractions. Median follow-up was 5.0 years for survivors. The 5-year failure-free survival estimate was 59% (95% confidence interval, 33-79%), and overall survival estimate was 64% (95% confidence interval, 37-82%). Among the 7 patients who failed, sites of first recurrence were local only (n = 2), regional only (n = 2), distant only (n = 2), and local and distant (n = 1). Late effects related to proton radiotherapy in the 10 recurrence-free patients (median follow-up, 5 years) include failure to maintain height velocity (n = 3), endocrinopathies (n = 2), mild facial hypoplasia (n = 7), failure of permanent tooth eruption (n = 3), dental caries (n = 5), and chronic nasal/sinus congestion (n = 2). Conclusions: Proton radiotherapy for patients with PM-RMS yields tumor control and survival comparable to that in historical controls with similar poor prognostic factors. Furthermore, rates of late effects from proton radiotherapy compare favorably to published reports of photon-treated cohorts.

Adult survival and population growth rate in Colorado big brown bats (Eptesicus fuscus)

Science.gov (United States)

O'Shea, T.J.; Ellison, L.E.; Stanley, T.R.

2011-01-01

We studied adult survival and population growth at multiple maternity colonies of big brown bats (Eptesicus fuscus) in Fort Collins, Colorado. We investigated hypotheses about survival using information-theoretic methods and mark-recapture analyses based on passive detection of adult females tagged with passive integrated transponders. We constructed a 3-stage life-history matrix model to estimate population growth rate (??) and assessed the relative importance of adult survival and other life-history parameters to population growth through elasticity and sensitivity analysis. Annual adult survival at 5 maternity colonies monitored from 2001 to 2005 was estimated at 0.79 (95% confidence interval [95% CI] = 0.77-0.82). Adult survival varied by year and roost, with low survival during an extreme drought year, a finding with negative implications for bat populations because of the likelihood of increasing drought in western North America due to global climate change. Adult survival during winter was higher than in summer, and mean life expectancies calculated from survival estimates were lower than maximum longevity records. We modeled adult survival with recruitment parameter estimates from the same population. The study population was growing (?? = 1.096; 95% CI = 1.057-1.135). Adult survival was the most important demographic parameter for population growth. Growth clearly had the highest elasticity to adult survival, followed by juvenile survival and adult fecundity (approximately equivalent in rank). Elasticity was lowest for fecundity of yearlings. The relative importances of the various life-history parameters for population growth rate are similar to those of large mammals. ?? 2011 American Society of Mammalogists.

Proton radiotherapy in management of pediatric base of skull tumors

International Nuclear Information System (INIS)

Hug, Eugen B.; Sweeney, Reinhart A.; Nurre, Pamela M.; Holloway, Kitty C.; Slater, Jerry D.; Munzenrider, John E.

2002-01-01

Purpose: Primary skull base tumors of the developing child are rare and present a formidable challenge to both surgeons and radiation oncologists. Gross total resection with negative margins is rarely achieved, and the risks of functional, structural, and cosmetic deficits limit the radiation dose using conventional radiation techniques. Twenty-nine children and adolescents treated with conformal proton radiotherapy (proton RT) were analyzed to assess treatment efficacy and safety. Methods and Materials: Between July 1992 and April 1999, 29 patients with mesenchymal tumors underwent fractionated proton (13 patients) or fractionated combined proton and photon (16 patients) irradiation. The age at treatment ranged from 1 to 19 years (median 12); 14 patients were male and 15 female. Tumors were grouped as malignant or benign. Twenty patients had malignant histologic findings, including chordoma (n=10), chondrosarcoma (n=3), rhabdomyosarcoma (n=4), and other sarcomas (n=3). Target doses ranged between 50.4 and 78.6 Gy/cobalt Gray equivalent (CGE), delivered at doses of 1.8-2.0 Gy/CGE per fraction. The benign histologic findings included giant cell tumors (n=6), angiofibromas (n=2), and chondroblastoma (n=1). RT doses for this group ranged from 45.0 to 71.8 Gy/CGE. Despite maximal surgical resection, 28 (97%) of 29 patients had gross disease at the time of proton RT. Follow-up after proton RT ranged from 13 to 92 months (mean 40). Results: Of the 20 patients with malignant tumors, 5 (25%) had local failure; 1 patient had failure in the surgical access route and 3 patients developed distant metastases. Seven patients had died of progressive disease at the time of analysis. Local tumor control was maintained in 6 (60%) of 10 patients with chordoma, 3 (100%) of 3 with chondrosarcoma, 4 (100%) of 4 with rhabdomyosarcoma, and 2 (66%) of 3 with other sarcomas. The actuarial 5-year local control and overall survival rate was 72% and 56%, respectively, and the overall survival

Repeated proton beam therapy for hepatocellular carcinoma

International Nuclear Information System (INIS)

Hashimoto, Takayuki; Tokuuye, Koichi; Fukumitsu, Nobuyoshi; Igaki, Hiroshi; Hata, Masaharu; Kagei, Kenji; Sugahara, Shinji; Ohara, Kiyoshi; Matsuzaki, Yasushi; Akine, Yasuyuki

2006-01-01

Purpose: To retrospectively evaluate the safety and effectiveness of repeated proton beam therapy for newly developed or recurrent hepatocellular carcinoma (HCC). Methods and Materials: From June 1989 through July 2000, 225 patients with HCC underwent their first course of proton beam therapy at University of Tsukuba. Of them, 27 with 68 lesions who had undergone two or more courses were retrospectively reviewed in this study. Median interval between the first and second course was 24.5 months (range 3.3-79.8 months). Median total dose of 72 Gy in 16 fractions and 66 Gy in 16 fractions were given for the first course and the rest of the courses, respectively. Results: The 5-year survival rate and median survival period from the beginning of the first course for the 27 patients were 55.6% and 62.2 months, respectively. Five-year local control rate for the 68 lesions was 87.8%. Of the patients, 1 with Child-Pugh class B and another with class C before the last course suffered from acute hepatic failure. Conclusions: Repeated proton beam therapy for HCC is safe when the patient has a target in the peripheral region of the liver and liver function is Child-Pugh class A

Colonial Legal Reasoning in the Post-Colonial African State: A ...

African Journals Online (AJOL)

Colonial Legal Reasoning in the Post-Colonial African State: A Critique and a Defense of the Argument from African Metaphysical Epistemology. ... Africa, as it has the advantageous result of helping in the search for truth concerning such offences, thereby promoting the delivery of effective legal justice, and thus contributing ...

The future and progress of proton beam radiotherapy

International Nuclear Information System (INIS)

Tsujii, Hirohiko

1994-01-01

The advantage of proton therapy is reduction of treatment volumes relative to those feasible with conventional photon therapy. The consequence is that the radiation dose to the target can be raised, with a resultant increase in tumor control probability. Proton beams, however, yield no biological gains because their biological properties are similar to conventional low LET radiations. As more sophisticated technologies are needed, there have been many advances which are applicable to photon therapy; 3-D treatment planning, DVH analysis, and systems for positioning, etc. As of January 1994, a total of about 13,000 cases were reported as having had treatments with proton beams in 16 centers world wide. The tumor sites for those include uveal melanoma (30-40%), intra-cranial small targets (40%), and others. Uveal melanomas had been most extensively treated with 70 Gy/5 fx or 60 Gy/4 fx which resulted in local control and survival rates of >96% and 80%, respectively. For chordoma and chondrosarcoma of the skull base and cervical spine, the 5 year local control rates were 65% and 91%, respectively. Promising results are also being obtained for head and neck and pelvic tumors. Deeper-seated tumors have been treated only at Tsukuba University with successful results in some anatomic sites. Among these, inoperable primary hepatocellular carcinomas were effectively treated with a total dose of 75-85 Gy (3.0-4.5 Gy/fx). The 3 year survival rates for all patients, Child A+B patient, and Child A patients were 38%, 47%, and 60%, respectively, which compare favorably to other modalities. These successful results of world wide proton therapy have led us to the conclusion that a hospital-based proton facility will provide opportunities for additional patients to be treated with protons. Thus, new plans are proposed from more than 10 institutions to build a new treatment center or upgrade the energy of currently available proton beams. (author)

Life in the colonies: learning the alien ways of colonial organisms.

Science.gov (United States)

Winston, Judith E

2010-12-01

Who needs to go to outer space to study alien beings when the oceans of our own planet abound with bizarre and unknown creatures? Many of them belong to sessile clonal and colonial groups, including sponges, hydroids, corals, octocorals, ascidians, bryozoans, and some polychaetes. Their life histories, in many ways unlike our own, are a challenge for biologists. Studying their ecology, behavior, and taxonomy means trying to “think like a colony” to understand the factors important in their lives. Until the 1980s, most marine ecologists ignored these difficult modular organisms. Plant ecologists showed them ways to deal with the two levels of asexually produced modules and genetic individuals, leading to a surge in research on the ecology of clonal and colonial marine invertebrates. Bryozoans make excellent model colonial animals. Their life histories range from ephemeral to perennial. Aspects of their lives such as growth, reproduction, partial mortality due to predation or fouling, and the behavior of both autozooids and polymorphs can be studied at the level of the colony, as well as that of the individual module, in living colonies and over time.

Loss of the ability to generate large burst-forming unit-like megakaryocytic colonies from thawed cord blood in semisolid cultures after short term suspension culture.

Science.gov (United States)

Eskola, M; Bäckman, S; Möttönen, S; Kekomäki, R

2015-04-01

Total colony-forming cells from thawed cord blood units (CBUs) include megakaryocytic colony-forming units (CFU-Mks), which survive the freezing process. The aim of this study was to evaluate whether different megakaryocytic progenitors from unseparated CBUs survive the freezing process and a short-term liquid culture. Thawed samples of CBUs were cultured in liquid medium. During the cultures, serial samples were drawn to assess the growth of different megakaryocytic progenitors in a semisolid collagen medium with identical cytokines as in the liquid medium. Megakaryocytic cells were detected using immunohistochemistry and flow cytometry. In suspension culture, the megakaryocytic progenitors almost completely lost the ability to generate large (burst-forming unit-like, BFU-like) megakaryocytic colonies in semisolid cultures (large colonies, median count per chamber d0: 7.25 vs. d7: 1.5; P culture in suspension resulted in the decline of small colonies as well (d7: 16.0 vs. d14: 5.75; P = 0.0088). Total CFU-Mk count declined from 23.3 (range 12.5-34.0) at d0 to 7.25 (range 1.0-13.5) at d14 (P culture after a short suspension culture. Small CFU-Mks were observed throughout the cultures. It may be that the BFU-Mk colonies matured and acquired CFU-Mk behaviour. © 2014 International Society of Blood Transfusion.

Queen Quality and the Impact of Honey Bee Diseases on Queen Health: Potential for Interactions between Two Major Threats to Colony Health

Directory of Open Access Journals (Sweden)

Esmaeil Amiri

2017-05-01

Full Text Available Western honey bees, Apis mellifera, live in highly eusocial colonies that are each typically headed by a single queen. The queen is the sole reproductive female in a healthy colony, and because long-term colony survival depends on her ability to produce a large number of offspring, queen health is essential for colony success. Honey bees have recently been experiencing considerable declines in colony health. Among a number of biotic and abiotic factors known to impact colony health, disease and queen failure are repeatedly reported as important factors underlying colony losses. Surprisingly, there are relatively few studies on the relationship and interaction between honey bee diseases and queen quality. It is critical to understand the negative impacts of pests and pathogens on queen health, how queen problems might enable disease, and how both factors influence colony health. Here, we review the current literature on queen reproductive potential and the impacts of honey bee parasites and pathogens on queens. We conclude by highlighting gaps in our knowledge on the combination of disease and queen failure to provide a perspective and prioritize further research to mitigate disease, improve queen quality, and ensure colony health.

Music from Ground Zero. The coloniality of theory and musical analysis at the university.

Directory of Open Access Journals (Sweden)

Pilar Jovanna Holguín

2018-01-01

Full Text Available This article seeks to answer the influence of the coloniality of knowledge, the cleansing of blood and the hybris of the zero ground in the conception of the theory and musical analysis which is taught in our Latin American universities. The aim is to examine the survival of coloniality in the imaginary of musical theory and analysis in order to recognize the predominant hegemonic discourses and propose some options to decolonize these disciplines of professional music education. The rationale is based on the presentation of some concepts of decolonial studies, research on the conservatory model and the ideology of theory and analysis.The article is divided into three parts. In the first one, an approximation is made to the concept of coloniality and its categories. The second takes the categories to review the ideology of the chosen fields of musical knowledge and the third proposes some options to decolonize our conceptions in higher education.

Spot Scanning and Passive Scattering Proton Therapy: Relative Biological Effectiveness and Oxygen Enhancement Ratio in Cultured Cells.

Science.gov (United States)

Iwata, Hiromitsu; Ogino, Hiroyuki; Hashimoto, Shingo; Yamada, Maho; Shibata, Hiroki; Yasui, Keisuke; Toshito, Toshiyuki; Omachi, Chihiro; Tatekawa, Kotoha; Manabe, Yoshihiko; Mizoe, Jun-etsu; Shibamoto, Yuta

2016-05-01

To determine the relative biological effectiveness (RBE), oxygen enhancement ratio (OER), and contribution of the indirect effect of spot scanning proton beams, passive scattering proton beams, or both in cultured cells in comparison with clinically used photons. The RBE of passive scattering proton beams at the center of the spread-out Bragg peak (SOBP) was determined from dose-survival curves in 4 cell lines using 6-MV X rays as controls. Survival of 2 cell lines after spot scanning and passive scattering proton irradiation was then compared. Biological effects at the distal end region of the SOBP were also investigated. The OER of passive scattering proton beams and 6 MX X rays were investigated in 2 cell lines. The RBE and OER values were estimated at a 10% cell survival level. The maximum degree of protection of radiation effects by dimethyl sulfoxide was determined to estimate the contribution of the indirect effect against DNA damage. All experiments comparing protons and X rays were made under the same biological conditions. The RBE values of passive scattering proton beams in the 4 cell lines examined were 1.01 to 1.22 (average, 1.14) and were almost identical to those of spot scanning beams. Biological effects increased at the distal end of the SOBP. In the 2 cell lines examined, the OER was 2.74 (95% confidence interval, 2.56-2.80) and 3.08 (2.84-3.11), respectively, for X rays, and 2.39 (2.38-2.43) and 2.72 (2.69-2.75), respectively, for protons (Pcells between X rays and protons). The maximum degree of protection was significantly higher for X rays than for proton beams (P<.05). The RBE values of spot scanning and passive scattering proton beams were almost identical. The OER was lower for protons than for X rays. The lower contribution of the indirect effect may partly account for the lower OER of protons. Copyright © 2016 Elsevier Inc. All rights reserved.

Yeast Colonies: A Model for Studies of Aging, Environmental Adaptation, and Longevity

OpenAIRE

Libuše Váchová; Michal Čáp; Zdena Palková

2012-01-01

When growing on solid surfaces, yeast, like other microorganisms, develops organized multicellular populations (colonies and biofilms) that are composed of differentiated cells with specialized functions. Life within these populations is a prevalent form of microbial existence in natural settings that provides the cells with capabilities to effectively defend against environmental attacks as well as efficiently adapt and survive long periods of starvation and other stresses. Under such circum...

The influence of interleukin-2, feeder cells, and timing of irradiation on the radiosensitivity of human T lymphocytes assessed by the colony-forming assay

International Nuclear Information System (INIS)

Gerber, M.; Guichard, M.; Pioch, Y.; Dubois, J.B.

1989-01-01

The radiosensitivity of human lymphocytes was investigated by the method of colony formation in the absence of interleukin-2 (IL2) and feeder cells, both of which enhance growth of T-cell colonies. The shape of the survival curve and the radiosensitivity was shown to depend upon the ability of lymphocytes to produce IL2: the survival curve for lymphocytes that were the most competent producers of IL2 is the closest to linearity; the lymphocytes that were poor producers show biphasic survival curves. The radiosensitivity of the lymphocytes from the first group is less than that of the latter, when the comparison is based on the first part of the biphasic survival curve. This is more easily seen when cultures are irradiated 24 h after stimulation by phytohemagglutinin (the time of the peak IL2 production) than when cultures are irradiated 2 h before stimulation. This study demonstrates that growth conditions influence the response of lymphocytes to irradiation and that optimal growth conditions result in a linear survival curve

Lysophosphatidic Acid Upregulates Laminin-332 Expression during A431 Cell Colony Dispersal

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Hironobu Yamashita

2010-01-01

Full Text Available Lysophosphatidic acid (LPA is a bioactive phospholipid that affects various biological functions, such as cell proliferation, migration, survival, wound healing, and tumor invasion through LPA receptors. Previously, we reported that LPA induces A431 colony dispersal, accompanied by disruption of cell-cell contacts and cell migration. However, it remains unclear how LPA affects cell migration and gene expression during A431 colony dispersal. In this paper, we performed cDNA microarray analysis to investigate this question by comparing gene expression between untreated and LPA-treated A431 cells. Interestingly, these results revealed that LPA treatment upregulates several TGF-β1 target genes, including laminin-332 (Ln-332 components (α3, β3, and γ2 chains. Western blot analysis also showed that LPA increased phosphorylation of Smad2, an event that is carried out by TGF-β1 interactions. Among the genes upregulated, we further addressed the role of Ln-332. Real-time PCR analysis confirmed the transcriptional upregulation of all α3, β3, and γ2 chains of Ln-332 by LPA, corresponding to the protein level increases revealed by western blot. Further, the addition of anti-Ln-332 antibody prevented LPA-treated A431 colonies from dispersing. Taken together, our results suggest that LPA-induced Ln-332 plays a significant role in migration of individual cells from A431 colonies.

Reirradiation of Head and Neck Cancers With Proton Therapy: Outcomes and Analyses

Energy Technology Data Exchange (ETDEWEB)

Phan, Jack [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Sio, Terence T. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Radiation Oncology, Mayo Clinic, Scottsdale, Arizona (United States); Nguyen, Theresa P. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Takiar, Vinita [Department of Radiation Oncology, University of Cincinnati, Cincinnati, Ohio (United States); Gunn, G. Brandon; Garden, Adam S.; Rosenthal, David I.; Fuller, Clifton D.; Morrison, William H.; Beadle, Beth; Ma, Dominic [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Zafereo, Mark E. [Department of Head and Neck Surgery, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Hutcheson, Kate A. [Department of Speech Pathology University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Kupferman, Michael E. [Department of Head and Neck Surgery, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); William, William N. [Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Frank, Steven J., E-mail: sjfrank@mdanderson.org [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

2016-09-01

Purpose: Reirradiation of head and neck (H&N) cancer is a clinical challenge. Proton radiation therapy (PRT) offers dosimetric advantages for normal tissue sparing and may benefit previously irradiated patients. Here, we report our initial experience with the use of PRT for H&N reirradiation, with focus on clinical outcomes and toxicity. Methods and Materials: We retrospectively reviewed the records of patients who received H&N reirradiation with PRT from April 2011 through June 2015. Patients reirradiated with palliative intent or without prior documentation of H&N radiation therapy were excluded. Radiation-related toxicities were recorded according to the Common Terminology Criteria for Adverse Events Version 4.0. Results: The conditions of 60 patients were evaluated, with a median follow-up time of 13.6 months. Fifteen patients (25%) received passive scatter proton therapy (PSPT), and 45 (75%) received intensity modulated proton therapy (IMPT). Thirty-five patients (58%) received upfront surgery, and 44 (73%) received concurrent chemotherapy. The 1-year rates of locoregional failure–free survival, overall survival, progression-free survival, and distant metastasis–free survival were 68.4%, 83.8%, 60.1%, and 74.9%, respectively. Eighteen patients (30%) experienced acute grade 3 (G3) toxicity, and 13 (22%) required a feeding tube at the end of PRT. The 1-year rates of late G3 toxicity and feeding tube independence were 16.7% and 2.0%, respectively. Three patients may have died of reirradiation-related effects (1 acute and 2 late). Conclusions: Proton beam therapy can be a safe and effective curative reirradiation strategy, with acceptable rates of toxicity and durable disease control.

Reirradiation of Head and Neck Cancers With Proton Therapy: Outcomes and Analyses

International Nuclear Information System (INIS)

Phan, Jack; Sio, Terence T.; Nguyen, Theresa P.; Takiar, Vinita; Gunn, G. Brandon; Garden, Adam S.; Rosenthal, David I.; Fuller, Clifton D.; Morrison, William H.; Beadle, Beth; Ma, Dominic; Zafereo, Mark E.; Hutcheson, Kate A.; Kupferman, Michael E.; William, William N.; Frank, Steven J.

2016-01-01

Purpose: Reirradiation of head and neck (H&N) cancer is a clinical challenge. Proton radiation therapy (PRT) offers dosimetric advantages for normal tissue sparing and may benefit previously irradiated patients. Here, we report our initial experience with the use of PRT for H&N reirradiation, with focus on clinical outcomes and toxicity. Methods and Materials: We retrospectively reviewed the records of patients who received H&N reirradiation with PRT from April 2011 through June 2015. Patients reirradiated with palliative intent or without prior documentation of H&N radiation therapy were excluded. Radiation-related toxicities were recorded according to the Common Terminology Criteria for Adverse Events Version 4.0. Results: The conditions of 60 patients were evaluated, with a median follow-up time of 13.6 months. Fifteen patients (25%) received passive scatter proton therapy (PSPT), and 45 (75%) received intensity modulated proton therapy (IMPT). Thirty-five patients (58%) received upfront surgery, and 44 (73%) received concurrent chemotherapy. The 1-year rates of locoregional failure–free survival, overall survival, progression-free survival, and distant metastasis–free survival were 68.4%, 83.8%, 60.1%, and 74.9%, respectively. Eighteen patients (30%) experienced acute grade 3 (G3) toxicity, and 13 (22%) required a feeding tube at the end of PRT. The 1-year rates of late G3 toxicity and feeding tube independence were 16.7% and 2.0%, respectively. Three patients may have died of reirradiation-related effects (1 acute and 2 late). Conclusions: Proton beam therapy can be a safe and effective curative reirradiation strategy, with acceptable rates of toxicity and durable disease control.

Effects of proton beam irradiation on seed germination and growth of soybean ( Glycine max L. Merr.)

Science.gov (United States)

Im, Juhyun; Kim, Woon Ji; Kim, Sang Hun; Ha, Bo-Keun

2017-12-01

The present study aimed to evaluate the morphological effects of proton beam irradiation on the seed germination, seedling survival, and plant growth of soybean. Seeds of three Korean elite cultivars (Kwangankong, Daepungkong, and Pungsannamulkong) were irradiated with a 57-MeV proton beam in the range of 50 - 400 Gy. The germination rates of all the varieties increased to > 95%; however, the survival rates were significantly reduced. At doses of > 300 Gy irradiation, the Daepungkong, Kwangankong, and Pungsannamulkong cultivars exhibited 39, 75, and 71% survival rates, respectively. In addition, plant height and the fresh weight of shoots and roots were significantly decreased by doses of > 100 Gy irradiation, as were the dry weights of the shoots and roots. However, SPAD values increased with increasing doses of irradiation. Abnormal plants with atypically branched stems, modified leaves, and chlorophyll mutations were observed. Based on the survival rate, plant growth inhibition, and mutation frequency, it appears that the optimum dosage of proton beam irradiation for soybean mutation breeding is between 250 and 300 Gy.

Spatial Arrangement of Colonies in Intact Biofilms from a Model Cooling Water System

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Michael Taylor

2013-01-01

Full Text Available There is disagreement among microbiologists about whether Legionella requires a protozoan host in order to replicate. This research sought to determine where in biofilm Legionellae are found and whether all biofilm associated Legionella would be located within protozoan hosts. While it is accepted that Legionella colonizes biofilm, its life cycle and nutritional fastidiousness suggest that Legionella employs multiple survival strategies to persist within microbial systems. Fluorescent in situ hybridization (FISH and confocal laser scanning microscopy (CLSM demonstrated an undulating biofilm surface architecture and a roughly homogenous distribution of heterotrophic bacteria with clusters of protozoa. Legionella displayed 3 distinct spatial arrangements either contained within or directly associated with protozoa, or dispersed in loosely associated clusters or in tightly packed aggregations of cells forming dense colonial clusters. The formation of discreet clusters of tightly packed Legionella suggests that colony formation is influenced by specific environmental conditions allowing for limited extracellular replication. This work represents the first time that an environmentally representative, multispecies biofilm containing Legionella has been fluorescently tagged and Legionella colony morphology noted within a complex microbial system.

Norwegian honey bees surviving Varroa destructor mite infestations by means of natural selection

OpenAIRE

Oddie, Melissa AY; Dahle, Bjørn Steinar; Neumann, Peter

2017-01-01

Background Managed, feral and wild populations of European honey bee subspecies, Apis mellifera, are currently facing severe colony losses globally. There is consensus that the ectoparasitic mite Varroa destructor, that switched hosts from the Eastern honey bee Apis cerana to the Western honey bee A. mellifera, is a key factor driving these losses. For >20 years, breeding efforts have not produced European honey bee colonies that can survive infestations without the need for mite control....

Long-Term Outcomes After Proton Beam Therapy for Sinonasal Squamous Cell Carcinoma

Energy Technology Data Exchange (ETDEWEB)

Russo, Andrea L.; Adams, Judith A.; Weyman, Elizabeth A.; Busse, Paul M.; Goldberg, Saveli I. [Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Varvares, Mark; Deschler, Daniel D.; Lin, Derrick T. [Head and Neck Surgical Oncology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts (United States); Delaney, Thomas F. [Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Chan, Annie W., E-mail: awchan@partners.org [Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States)

2016-05-01

Purpose: Squamous cell carcinoma (SCC) is the most common sinonasal cancer and is associated with one of the poor outcomes. Proton therapy allows excellent target coverage with maximal sparing of adjacent normal tissues. We evaluated the long-term outcomes in patients with sinonasal SCC treated with proton therapy. Methods and Materials: Between 1991 and 2008, 54 patients with Stage III and IV SCC of the nasal cavity and paranasal sinus received proton beam therapy at our institution to a median dose of 72.8 Gy(RBE). Sixty-nine percent underwent prior surgical resection, and 74% received elective nodal radiation. Locoregional control and survival probabilities were estimated with the Kaplan-Meier method. Multivariate analyses were performed using the Cox proportional-hazards model. Treatment toxicity was scored using the Common Terminology Criteria for Adverse Events version 4.0. Results: With a median follow-up time of 82 months in surviving patients, there were 10 local, 7 regional, and 11 distant failures. The 2-year and 5-year actuarial local control rate was 80%. The 2-year and 5-year rates of overall survival were 67% and 47%, respectively. Only smoking status was predictive for worse locoregional control, with current smokers having a 5-year rate of 23% compared with 83% for noncurrent smokers (P=.004). Karnofsky performance status ≤80 was the most significant factor predictive for worse overall survival in multivariate analysis (adjusted hazard ratio 4.5, 95% confidence interval 1.6-12.5, P=.004). There were nine grade 3 and six grade 4 toxicities, and no grade 5 toxicity. Wound adverse events constituted the most common grade 3-4 toxicity. Conclusions: Our long-term results show that proton radiation therapy is well tolerated and yields good locoregional control for SCC of the nasal cavity and paranasal sinus. Current smokers and patients with poor performance status had inferior outcomes. Prospective study is necessary to compare IMRT with proton

Long-Term Outcomes After Proton Beam Therapy for Sinonasal Squamous Cell Carcinoma

International Nuclear Information System (INIS)

Russo, Andrea L.; Adams, Judith A.; Weyman, Elizabeth A.; Busse, Paul M.; Goldberg, Saveli I.; Varvares, Mark; Deschler, Daniel D.; Lin, Derrick T.; Delaney, Thomas F.; Chan, Annie W.

2016-01-01

Purpose: Squamous cell carcinoma (SCC) is the most common sinonasal cancer and is associated with one of the poor outcomes. Proton therapy allows excellent target coverage with maximal sparing of adjacent normal tissues. We evaluated the long-term outcomes in patients with sinonasal SCC treated with proton therapy. Methods and Materials: Between 1991 and 2008, 54 patients with Stage III and IV SCC of the nasal cavity and paranasal sinus received proton beam therapy at our institution to a median dose of 72.8 Gy(RBE). Sixty-nine percent underwent prior surgical resection, and 74% received elective nodal radiation. Locoregional control and survival probabilities were estimated with the Kaplan-Meier method. Multivariate analyses were performed using the Cox proportional-hazards model. Treatment toxicity was scored using the Common Terminology Criteria for Adverse Events version 4.0. Results: With a median follow-up time of 82 months in surviving patients, there were 10 local, 7 regional, and 11 distant failures. The 2-year and 5-year actuarial local control rate was 80%. The 2-year and 5-year rates of overall survival were 67% and 47%, respectively. Only smoking status was predictive for worse locoregional control, with current smokers having a 5-year rate of 23% compared with 83% for noncurrent smokers (P=.004). Karnofsky performance status ≤80 was the most significant factor predictive for worse overall survival in multivariate analysis (adjusted hazard ratio 4.5, 95% confidence interval 1.6-12.5, P=.004). There were nine grade 3 and six grade 4 toxicities, and no grade 5 toxicity. Wound adverse events constituted the most common grade 3-4 toxicity. Conclusions: Our long-term results show that proton radiation therapy is well tolerated and yields good locoregional control for SCC of the nasal cavity and paranasal sinus. Current smokers and patients with poor performance status had inferior outcomes. Prospective study is necessary to compare IMRT with proton

Seabird Colonies in Western Greenland

DEFF Research Database (Denmark)

Boertmann, D.; Mosbech, A.; Falk, K.

About 1 million seabirds (indvs) breed in 1032 colonies distributed along the coasts of western Greenland (Fig. 1). However, this figure does not include the little auk colonies in Avanersuaq. These colonies are roughly estimated to hold about 20 mill. pairs. All the basic information on seabird...... colonies in Greenland is compiled in a database maintained by NERI-AE. This report presents data on distribution, population numbers and population trends of 19 species of breeding colonial seabirds in western Greenland. Distributions are depicted on maps in Fig. 18-39. It is apparent that the major...... colonies are found in the northern part of the region, viz. Upernavik and Avanersuaq. The numbers of birds recorded in the database for each species are presented in Tab. 4, and on the basis of these figures estimates of the populations in western Greenland are given (Tab. 5). The most numerous species...

Advances in compact proton spectrometers for inertial-confinement fusion and plasma nuclear science.

Science.gov (United States)

Seguin, F H; Sinenian, N; Rosenberg, M; Zylstra, A; Manuel, M J-E; Sio, H; Waugh, C; Rinderknecht, H G; Johnson, M Gatu; Frenje, J; Li, C K; Petrasso, R; Sangster, T C; Roberts, S

2012-10-01

Compact wedge-range-filter proton spectrometers cover proton energies ∼3-20 MeV. They have been used at the OMEGA laser facility for more than a decade for measuring spectra of primary D(3)He protons in D(3)He implosions, secondary D(3)He protons in DD implosions, and ablator protons in DT implosions; they are now being used also at the National Ignition Facility. The spectra are used to determine proton yields, shell areal density at shock-bang time and compression-bang time, fuel areal density, and implosion symmetry. There have been changes in fabrication and in analysis algorithms, resulting in a wider energy range, better accuracy and precision, and better robustness for survivability with indirect-drive inertial-confinement-fusion experiments.

Coral restoration Bonaire : an evaluation of growth, regeneration and survival

NARCIS (Netherlands)

Meesters, H.W.G.; Boomstra, B.; Hurtado-Lopez, N.; Montbrun, A.; Virdis, F.

2015-01-01

The Coral restoration of Staghorn (Acropora cervicornis) and Elkhorn (A. palmata) as practiced by the Coral Restoration Foundation Bonaire (CRFB) is shown to be highly successful in terms of growth and survival of new colonies, in both nurseries and transplant locations. Coral restoration is

Colony Dimorphism in Bradyrhizobium Strains

Science.gov (United States)

Sylvester-Bradley, Rosemary; Thornton, Philip; Jones, Peter

1988-01-01

Ten isolates of Bradyrhizobium spp. which form two colony types were studied; the isolates originated from a range of legume species. The two colony types differed in the amount of gum formed or size or both, depending on the strain. Whole 7-day-old colonies of each type were subcultured to determine the proportion of cells which had changed to the other type. An iterative computerized procedure was used to determine the rate of switching per generation between the two types and to predict proportions reached at equilibrium for each strain. The predicted proportions of the wetter (more gummy) or larger colony type at equilibrium differed significantly between strains, ranging from 0.9999 (strain CIAT 2383) to 0.0216 (strain CIAT 2469), because some strains switched faster from dry to wet (or small to large) and others switched faster from wet to dry (or large to small). Predicted equilibrium was reached after about 140 generations in strain USDA 76. In all but one strain (CIAT 3030) the growth rate of the wetter colony type was greater than or similar to that of the drier type. The mean difference in generation time between the two colony types was 0.37 h. Doubling times calculated for either colony type after 7 days of growth on the agar surface ranged from 6.0 to 7.3 h. The formation of two persistent colony types by one strain (clonal or colony dimorphism) may be a common phenomenon among Bradyrhizobium strains. Images PMID:16347599

Intraspecific Variation among Social Insect Colonies: Persistent Regional and Colony-Level Differences in Fire Ant Foraging Behavior.

Directory of Open Access Journals (Sweden)

Alison A Bockoven

Full Text Available Individuals vary within a species in many ecologically important ways, but the causes and consequences of such variation are often poorly understood. Foraging behavior is among the most profitable and risky activities in which organisms engage and is expected to be under strong selection. Among social insects there is evidence that within-colony variation in traits such as foraging behavior can increase colony fitness, but variation between colonies and the potential consequences of such variation are poorly documented. In this study, we tested natural populations of the red imported fire ant, Solenopsis invicta, for the existence of colony and regional variation in foraging behavior and tested the persistence of this variation over time and across foraging habitats. We also reared single-lineage colonies in standardized environments to explore the contribution of colony lineage. Fire ants from natural populations exhibited significant and persistent colony and regional-level variation in foraging behaviors such as extra-nest activity, exploration, and discovery of and recruitment to resources. Moreover, colony-level variation in extra-nest activity was significantly correlated with colony growth, suggesting that this variation has fitness consequences. Lineage of the colony had a significant effect on extra-nest activity and exploratory activity and explained approximately half of the variation observed in foraging behaviors, suggesting a heritable component to colony-level variation in behavior.

The Mediterranean stony coral Cladocora caespitosa (Linnaeus, 1767) as habitat provider for molluscs: colony size effect

Science.gov (United States)

Pitacco, Valentina; Crocetta, Fabio; Orlando-Bonaca, Martina; Mavrič, Borut; Lipej, Lovrenc

2017-11-01

The stony coral Cladocora caespitosa (Linnaeus, 1767) is an important Mediterranean habitat builder, whose survival is now being threatened by human activities and possibly natural events such as mass mortality and bleaching. We characterized the mollusc assemblage associated with colonies in the Gulf of Trieste (northern Adriatic Sea) and then tested whether the number of mollusc species increases in relation with colony size, following a Species-Area Relationship (SAR) model. At least 62 taxa were found in association with coral colonies, with bivalves constituting the dominant group. More than half of the 3034 specimens encountered were juveniles. Mollusc taxa richness increased with increasing C. caespitosa colony size according to the power-function model, whilst the analyses of trophic and functional groups supports the hypothesis of at least two factors underlying SAR (area per se and habitat diversity). Our results confirmed the importance of C. caespitosa for benthic communities, indicating that larger colonies support higher biodiversity, and suggesting that C. caespitosa is the most important habit builder among Mediterranean cnidarians, having also an influential function as a natural nursery ground. These results underline the necessity of new investigations aimed at filling gaps in our knowledge and planning new measures to protect the species.

Avian cholera, a threat to the viability of an Arctic seabird colony?

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Sébastien Descamps

Full Text Available Evidence that infectious diseases cause wildlife population extirpation or extinction remains anecdotal and it is unclear whether the impacts of a pathogen at the individual level can scale up to population level so drastically. Here, we quantify the response of a Common eider colony to emerging epidemics of avian cholera, one of the most important infectious diseases affecting wild waterfowl. We show that avian cholera has the potential to drive colony extinction, even over a very short period. Extinction depends on disease severity (the impact of the disease on adult female survival and disease frequency (the number of annual epidemics per decade. In case of epidemics of high severity (i.e., causing >30% mortality of breeding females, more than one outbreak per decade will be unsustainable for the colony and will likely lead to extinction within the next century; more than four outbreaks per decade will drive extinction to within 20 years. Such severity and frequency of avian cholera are already observed, and avian cholera might thus represent a significant threat to viability of breeding populations. However, this will depend on the mechanisms underlying avian cholera transmission, maintenance, and spread, which are currently only poorly known.

Botryllus schlosseri (Tunicata) whole colony irradiation: Do senescent zooid resorption and immunological resorption involve similar recognition events

International Nuclear Information System (INIS)

Rinkevich, B.; Weissman, I.L.

1990-01-01

The colonial tunicate Botryllus schlosseri undergoes cyclic blastogenesis where feeding zooids are senescened and resorbed and a new generation of zooids takes over the colony. When non-identical colonies come into direct contact, they either reject each other or fuse. Fusion is usually followed by the resorption of one of the partners in the chimera (immunological resorption). The striking morphological similarities between the two resorption phenomena suggest that both may involve tissue destruction following self-nonself recognition events. Here we attempt to modify these two events by whole colony gamma irradiation assays. Three sets of experiments were performed: (1) different doses of whole colony irradiation for determination of irradiation effects (110 colonies); (2) pairs of irradiated-nonirradiated isografts of clonal replicates for the potential of reconstruction of the irradiated partners (23 pairs); (3) chimeras of irradiated-nonirradiated partners for analysis of resorption hierarchy. Mortality increased with the irradiation dose. All colonies exposed to more than 5,000 rads died within 19 days, while no colony died below 2,000 rads. The average mortality periods, in days, for doses of 6,000-8,000, 5,000, and 2,500-4,000 rads were 14.4 +/- 3.1 (n = 24), 19.8 +/- 6.0 (n = 15), and 19.6 + 5.1 (n = 22), respectively. Younger colonies (3-6 months old) may survive radiation better than older ones (more than 13 months). Many morphological alterations were recorded in irradiated colonies: ampullar contraction and/or dilation, accumulation of pigment cells within ampullae, abnormal bleeding from blood vessels, sluggish blood circulation, necrotic zones, reduction in bud number, and irregularities in zooid and system structures. With doses of 3,000-4,000 rads and above, irradiation arrested the formation of new buds and interrupted normal takeover

Colony structure in a plant-ant: behavioural, chemical and genetic study of polydomy in Cataulacus mckeyi (Myrmicinae).

Science.gov (United States)

Debout, Gabriel; Provost, Erick; Renucci, Marielle; Tirard, Alain; Schatz, Bertrand; McKey, Doyle

2003-10-01

Social organisation of colonies of obligate plant-ants can affect their interaction with myrmecophyte hosts and with other ants competing for the resources they offer. An important parameter of social organisation is whether nest sites of a colony include one or several host individuals. We determined colony boundaries in a plant-ant associated with the rainforest understorey tree Leonardoxa africana subsp. africana, found in coastal forests of Cameroon (Central Africa). This myrmecophyte is strictly associated with two ants, Petalomyrmex phylax and Cataulacus mckeyi. Plants provide food and nesting sites for P. phylax, which protects young leaves against insect herbivores. This mutualism is often parasitised by C. mckeyi, which uses but does not protect the host. The presence of C. mckeyi on a tree excludes the mutualistic ant. Because Petalomyrmex-occupied trees are better protected, their growth and survival are superior to those of Cataulacus-occupied trees, giving P. phylax an advantage in occupation of nest sites. C. mckeyi often colonises trees that have lost their initial associate P. phylax, as a result of injury to the tree caused by disturbance. Polydomy may allow C. mckeyi to occupy small clumps of trees, without the necessity of claustral colony foundation in each tree. Investigating both the proximate (behavioural repertoire, colony odour) and the ultimate factors (genetic structure) that may influence colony closure, we precisely defined colony boundaries. We show that colonies of C. mckeyi are monogynous and facultatively polydomous, i.e. a colony occupies one to several Leonardoxa trees. Workers do not produce males. Thus, the hypothesis that polydomy allows workers in queenless nests to evade queen control for their reproduction is not supported in this instance. This particular colony structure may confer on C. mckeyi an advantage in short-distance dispersal, and this could help explain its persistence within the dynamic Leonardoxa system.

Are Dispersal Mechanisms Changing the Host-Parasite Relationship and Increasing the Virulence of Varroa destructor (Mesostigmata: Varroidae) in Managed Honey Bee (Hymenoptera: Apidae) Colonies?

Science.gov (United States)

DeGrandi-Hoffman, Gloria; Ahumada, Fabiana; Graham, Henry

2017-08-01

Varroa (Varroa destructor Anderson and Trueman) are a serious pest of European honey bees (Apis mellifera L.), and difficult to control in managed colonies. In our 11-mo longitudinal study, we applied multiple miticide treatments, yet mite numbers remained high and colony losses exceeded 55%. High mortality from varroa in managed apiaries is a departure from the effects of the mite in feral colonies where bees and varroa can coexist. Differences in mite survival strategies and dispersal mechanisms may be contributing factors. In feral colonies, mites can disperse through swarming. In managed apiaries, where swarming is reduced, mites disperse on foragers robbing or drifting from infested hives. Using a honey bee-varroa population model, we show that yearly swarming curtails varroa population growth, enabling colony survival for >5 yr. Without swarming, colonies collapsed by the third year. To disperse, varroa must attach to foragers that then enter other hives. We hypothesize that stress from parasitism and virus infection combined with effects that viruses have on cognitive function may contribute to forager drift and mite and virus dispersal. We also hypothesize that drifting foragers with mites can measurably increase mite populations. Simulations initialized with field data indicate that low levels of drifting foragers with mites can create sharp increases in mite populations in the fall and heavily infested colonies in the spring. We suggest new research directions to investigate factors leading to mite dispersal on foragers, and mite management strategies with consideration of varroa as a migratory pest. Published by Oxford University Press on behalf of Entomological Society of America 2017. This work is written by US Government employees and is in the public domain in the US.

Kant's Second Thoughts on Colonialism

NARCIS (Netherlands)

Kleingeld, Pauline; Flikschuh, Katrin; Ypi, Lea

2014-01-01

Kant is widely regarded as a fierce critic of colonialism. In Toward Perpetual Peace and the Metaphysics of Morals, for example, he forcefully condemns European conduct in the colonies as a flagrant violation of the principles of right. His earlier views on colonialism have not yet received much

Behavioral Modulation of Infestation by Varroa destructor in Bee Colonies. Implications for Colony Stability.

Science.gov (United States)

de Figueiró Santos, Joyce; Coelho, Flávio Codeço; Bliman, Pierre-Alexandre

2016-01-01

Colony Collapse Disorder (CCD) has become a global problem for beekeepers and for the crops that depend on bee pollination. While many factors are known to increase the risk of colony collapse, the ectoparasitic mite Varroa destructor is considered to be the most serious one. Although this mite is unlikely to cause the collapse of hives itself, it is the vector for many viral diseases which are among the likely causes for Colony Collapse Disorder. The effects of V. destructor infestation differ from one part of the world to another, with greater morbidity and higher colony losses in European honey bees (EHB) in Europe, Asia and North America. Although this mite has been present in Brazil for many years, there have been no reports of colony losses amongst Africanized Honey Bees (AHB). Studies carried out in Mexico have highlighted different behavioral responses by the AHB to the presence of the mite, notably as far as grooming and hygienic behavior are concerned. Could these explain why the AHB are less susceptible to Colony Collapse Disorder? In order to answer this question, we have developed a mathematical model of the infestation dynamics to analyze the role of resistance behavior by bees in the overall health of the colony, and as a consequence, its ability to face epidemiological challenges.

Behavioral Modulation of Infestation by Varroa destructor in Bee Colonies. Implications for Colony Stability.

Directory of Open Access Journals (Sweden)

Joyce de Figueiró Santos

Full Text Available Colony Collapse Disorder (CCD has become a global problem for beekeepers and for the crops that depend on bee pollination. While many factors are known to increase the risk of colony collapse, the ectoparasitic mite Varroa destructor is considered to be the most serious one. Although this mite is unlikely to cause the collapse of hives itself, it is the vector for many viral diseases which are among the likely causes for Colony Collapse Disorder. The effects of V. destructor infestation differ from one part of the world to another, with greater morbidity and higher colony losses in European honey bees (EHB in Europe, Asia and North America. Although this mite has been present in Brazil for many years, there have been no reports of colony losses amongst Africanized Honey Bees (AHB. Studies carried out in Mexico have highlighted different behavioral responses by the AHB to the presence of the mite, notably as far as grooming and hygienic behavior are concerned. Could these explain why the AHB are less susceptible to Colony Collapse Disorder? In order to answer this question, we have developed a mathematical model of the infestation dynamics to analyze the role of resistance behavior by bees in the overall health of the colony, and as a consequence, its ability to face epidemiological challenges.

Colonialism, customary law and the post-colonial state in Africa: the ...

African Journals Online (AJOL)

Colonialism became a fact of life in many African countries. An effect of colonialism especially in the former British colonized countries was the transplantation of the British legal system, which led to recognition of both systems and the gradual relegation of the indigenous system otherwise called customary law. The use and ...

Public Heath in Colonial and Post-Colonial Ghana: Lesson-Drawing for The Twenty-First Century

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Adu-Gyamfi, Samuel

2017-06-01

Full Text Available Public health in twenty-first century Ghana is mired with several issues ranging from the inadequacy of public health facilities, improper settlement planning, insanitary conditions, and the inadequacy of laws and their implementation. This situation compared to the colonial era is a direct contradiction. Development in the pre-colonial era to the colonial era sought to make the prevention of diseases a priority in the colonial administration. This was begun with the establishment of the health branch in 1909 as a response to the bubonic plague that was fast spreading in the colony. From here public health policies and strategies were enacted to help the diseases prevention cause. Various public health boards, the medical research institute or the laboratory branch, the waste management department, the use of preventive medicine and maintenance of good settlement planning and sanitation were public health measures in the colonial era. This research seeks to analyse the public health system in the colonial era so as to draw basic lessons for twenty-first century Ghana. Archival data and other secondary sources are reviewed and analysed to help draw these lessons. Richard Rose’s lesson-drawing approach was used to draw the lessons.

Modification of survival and hematopoiesis in mice by tocopherol injection following irradiation

International Nuclear Information System (INIS)

Bichay, T.J.E.; Roy, R.M.

1986-01-01

The LD 50/30 of CD-1-female mice increased from 6.6 Gy to 7.0 Gy when 2.5 mg of dl-α-tocopherol was injected immediately post irradiation. Increased survival was associated with increased numbers of hematopoietic colony forming units (CFU). Endogeneous spleen colonies were found in greater numbers in the tocopherol-treated mice after irradiation. The vitamin, however, must be injected within five hours following irradiation to have this effect. The increased numbers of CFU in tocopherol-treated mice may be due to a stimulation of recovery of repair processes. Split-dose studies suggest that most repair of sublethal damage in hematopoietic stem cells take place within seven and nine hours following irradiation. Tocopherol injection appears to enhance the recovery manifested in the split-dose assay. There is also evidence that tocopherol-treatment caused an earlier onset of mitotic activity in CFU after irradiation. The increased number of spleen colonies in tocopherol-injected mice is not due to an altered CFU seeding efficiency associated with an altered spleen microenvironment. Tocopherol injection did not affect the shoulder of the stem cell survival curve using exogenous spleen colony assays of bone marrow-derived or spleen-derived hematopoietic stem cells. There appears to be a decrease in D 0 in the higher dose region (4.3 Gy) of the bone marrow exogenous SCA survival curves for the vehicle-injected and the non-injected groups; however, the tocopherol-injected group showed no evidence of change in radiosensitivity up to the highest dose used (5.0 Gy). Data may be interpreted to suggest that the therapeutic effect of tocopherol may involve repair of hematopoietic stem cell damage in the higher dose range of bone marrow syndrome. (orig.) [de

A connection between colony biomass and death in Caribbean reef-building corals.

Directory of Open Access Journals (Sweden)

Daniel J Thornhill

Full Text Available Increased sea-surface temperatures linked to warming climate threaten coral reef ecosystems globally. To better understand how corals and their endosymbiotic dinoflagellates (Symbiodinium spp. respond to environmental change, tissue biomass and Symbiodinium density of seven coral species were measured on various reefs approximately every four months for up to thirteen years in the Upper Florida Keys, United States (1994-2007, eleven years in the Exuma Cays, Bahamas (1995-2006, and four years in Puerto Morelos, Mexico (2003-2007. For six out of seven coral species, tissue biomass correlated with Symbiodinium density. Within a particular coral species, tissue biomasses and Symbiodinium densities varied regionally according to the following trends: Mexico≥Florida Keys≥Bahamas. Average tissue biomasses and symbiont cell densities were generally higher in shallow habitats (1-4 m compared to deeper-dwelling conspecifics (12-15 m. Most colonies that were sampled displayed seasonal fluctuations in biomass and endosymbiont density related to annual temperature variations. During the bleaching episodes of 1998 and 2005, five out of seven species that were exposed to unusually high temperatures exhibited significant decreases in symbiotic algae that, in certain cases, preceded further decreases in tissue biomass. Following bleaching, Montastraea spp. colonies with low relative biomass levels died, whereas colonies with higher biomass levels survived. Bleaching- or disease-associated mortality was also observed in Acropora cervicornis colonies; compared to A. palmata, all A. cervicornis colonies experienced low biomass values. Such patterns suggest that Montastraea spp. and possibly other coral species with relatively low biomass experience increased susceptibility to death following bleaching or other stressors than do conspecifics with higher tissue biomass levels.

A connection between colony biomass and death in Caribbean reef-building corals.

Science.gov (United States)

Thornhill, Daniel J; Rotjan, Randi D; Todd, Brian D; Chilcoat, Geoff C; Iglesias-Prieto, Roberto; Kemp, Dustin W; LaJeunesse, Todd C; Reynolds, Jennifer McCabe; Schmidt, Gregory W; Shannon, Thomas; Warner, Mark E; Fitt, William K

2011-01-01

Increased sea-surface temperatures linked to warming climate threaten coral reef ecosystems globally. To better understand how corals and their endosymbiotic dinoflagellates (Symbiodinium spp.) respond to environmental change, tissue biomass and Symbiodinium density of seven coral species were measured on various reefs approximately every four months for up to thirteen years in the Upper Florida Keys, United States (1994-2007), eleven years in the Exuma Cays, Bahamas (1995-2006), and four years in Puerto Morelos, Mexico (2003-2007). For six out of seven coral species, tissue biomass correlated with Symbiodinium density. Within a particular coral species, tissue biomasses and Symbiodinium densities varied regionally according to the following trends: Mexico≥Florida Keys≥Bahamas. Average tissue biomasses and symbiont cell densities were generally higher in shallow habitats (1-4 m) compared to deeper-dwelling conspecifics (12-15 m). Most colonies that were sampled displayed seasonal fluctuations in biomass and endosymbiont density related to annual temperature variations. During the bleaching episodes of 1998 and 2005, five out of seven species that were exposed to unusually high temperatures exhibited significant decreases in symbiotic algae that, in certain cases, preceded further decreases in tissue biomass. Following bleaching, Montastraea spp. colonies with low relative biomass levels died, whereas colonies with higher biomass levels survived. Bleaching- or disease-associated mortality was also observed in Acropora cervicornis colonies; compared to A. palmata, all A. cervicornis colonies experienced low biomass values. Such patterns suggest that Montastraea spp. and possibly other coral species with relatively low biomass experience increased susceptibility to death following bleaching or other stressors than do conspecifics with higher tissue biomass levels. © 2011 Thornhill et al.

Comparative study on the dynamics and performances of Apis mellifera jemenitica and imported hybrid honeybee colonies in southwestern Saudi Arabia.

Science.gov (United States)

Al-Ghamdi, Ahmad A; Adgaba, Nuru; Tadesse, Yilma; Getachew, Awraris; Al-Maktary, Anwer A

2017-07-01

The aims of this study were to assess the seasonal population dynamics and evaluate the performance of Apis mellifera jemenitica (local bee) and introduced hybrid honeybee colonies in the lowlands and highlands of southwestern Saudi Arabia. Data regarding the performance and population dynamics parameters such as brood and adult bee population, amounts of stored pollen and nectar were gathered from the two races (25 colonies of each) for one year (April 2013 through March 2014), and statistically tested. The results indicated that at low lands, local bee colonies maintained relatively high brood and adult bee populations ( P  bee colonies were able to hoard three times more ( P  pollen and built more ( P  bees in both the low and highland areas. The annual survival rate of local bee colonies was almost double ( P  bees had greater ( P  bee and brood populations than imported, throughout the year. The relatively good performance of local colonies could be due to their long year's adaptation to cope with resource scarcity and unpredictable environmental conditions of the regions. The possible reasons for the dwindling of the imported hybrid colonies could be due to continuing to exhibit adaptive characteristics of their original that might not fit well with the new environment.

Global Incorporation and Cultural Survival: The Surinamese Maroons at the Margins of the World-System

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Aonghas St.-Hilaire

2015-08-01

Full Text Available The Maroons of Suriname enter the twenty-? rst century as the only surviving, culturally and politically autonomous Maroon communities in the Americas. The paper adopts a world-systems approach to explain the evolution of the Surinamese Maroon nations vis-à-vis the ever expanding Surinamese state and global political economy, with particular attention paid to the cultural survival of the Maroon nations. Prior to emancipation, limited colonial integration and mutual fear between the Maroons and Surinamese coastal society facilitated the development of the Maroon communities as relatively independent nations. Despite the best efforts of colonial authorities after emancipation, the weak economy and infrastructure of the Surinamese colony as well as continued mutual fear and distrust enabled the Maroons to guard their autonomy. However, after the Second World War, a period of global economic expansion, the rapid development of the Suriname as an integrated political, economic and cultural unit, and the depletion of and strain on natural resources in traditional Maroon territory dealt serious blows to Maroon autonomy. Maroon cultural survival depends on the ability of the Maroon nations to navigate the rapid changes currently affecting Maroon society, guarding political autonomy and cultivating the most treasured aspects of their cultural heritage, while participating, albeit peripherally, in modern global capitalism.

Proton-air and proton-proton cross sections

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Ulrich Ralf

2013-06-01

Full Text Available Different attempts to measure hadronic cross sections with cosmic ray data are reviewed. The major results are compared to each other and the differences in the corresponding analyses are discussed. Besides some important differences, it is crucial to see that all analyses are based on the same fundamental relation of longitudinal air shower development to the observed fluctuation of experimental observables. Furthermore, the relation of the measured proton-air to the more fundamental proton-proton cross section is discussed. The current global picture combines hadronic proton-proton cross section data from accelerator and cosmic ray measurements and indicates a good consistency with predictions of models up to the highest energies.

A queen pheromone induces workers to kill sexual larvae in colonies of the red imported fire ant (Solenopsis invicta)

Science.gov (United States)

Klobuchar, Emily; Deslippe, Richard

2002-05-01

We conducted five bioassays to study how queens control the execution of sexual larvae by workers in colonies of the red imported fire ant, Solenopsis invicta. In each assay, subset colonies were made from many large polygyne colonies, and the 20 sexual larvae they contained were monitored over time. Sexual larvae mostly survived in queenless colonies, but were mostly killed in colonies with a single dealated queen, regardless of whether or not the queen was fertilized. The larvae were also killed when fresh corpses of queens were added to queenless colonies. Whereas acetone extracts of queens did not produce a significant increase in killings, extracts in buffered saline induced workers to execute most sexual larvae, indicating successful extraction of an execution pheromone. We identified the probable storage location of the chemical as the poison sac, and found both fresh (1 day) and old (21 day) extracts of poison sacs to be equally effective in inducing executions. The pheromone is stable at room temperature, perhaps because venom alkaloids also present in the extracts keep the pheromone from degrading. It is apparently either proteinaceous or associated with a proteinaceous molecule, a novel finding, as no queen pheromone of a proteinaceous nature has been previously demonstrated in ants.

Physical Forces Modulate Oxidative Status and Stress Defense Meditated Metabolic Adaptation of Yeast Colonies: Spaceflight and Microgravity Simulations

Science.gov (United States)

Hammond, Timothy G.; Allen, Patricia L.; Gunter, Margaret A.; Chiang, Jennifer; Giaever, Guri; Nislow, Corey; Birdsall, Holly H.

2018-05-01

Baker's yeast ( Saccharomyces cerevisiae) has broad genetic homology to human cells. Although typically grown as 1-2mm diameter colonies under certain conditions yeast can form very large (10 + mm in diameter) or `giant' colonies on agar. Giant yeast colonies have been used to study diverse biomedical processes such as cell survival, aging, and the response to cancer pharmacogenomics. Such colonies evolve dynamically into complex stratified structures that respond differentially to environmental cues. Ammonia production, gravity driven ammonia convection, and shear defense responses are key differentiation signals for cell death and reactive oxygen system pathways in these colonies. The response to these signals can be modulated by experimental interventions such as agar composition, gene deletion and application of pharmaceuticals. In this study we used physical factors including colony rotation and microgravity to modify ammonia convection and shear stress as environmental cues and observed differences in the responses of both ammonia dependent and stress response dependent pathways We found that the effects of random positioning are distinct from rotation. Furthermore, both true and simulated microgravity exacerbated both cellular redox responses and apoptosis. These changes were largely shear-response dependent but each model had a unique response signature as measured by shear stress genes and the promoter set which regulates them These physical techniques permitted a graded manipulation of both convection and ammonia signaling and are primed to substantially contribute to our understanding of the mechanisms of drug action, cell aging, and colony differentiation.

Physical Forces Modulate Oxidative Status and Stress Defense Meditated Metabolic Adaptation of Yeast Colonies: Spaceflight and Microgravity Simulations

Science.gov (United States)

Hammond, Timothy G.; Allen, Patricia L.; Gunter, Margaret A.; Chiang, Jennifer; Giaever, Guri; Nislow, Corey; Birdsall, Holly H.

2017-12-01

Baker's yeast (Saccharomyces cerevisiae) has broad genetic homology to human cells. Although typically grown as 1-2mm diameter colonies under certain conditions yeast can form very large (10 + mm in diameter) or `giant' colonies on agar. Giant yeast colonies have been used to study diverse biomedical processes such as cell survival, aging, and the response to cancer pharmacogenomics. Such colonies evolve dynamically into complex stratified structures that respond differentially to environmental cues. Ammonia production, gravity driven ammonia convection, and shear defense responses are key differentiation signals for cell death and reactive oxygen system pathways in these colonies. The response to these signals can be modulated by experimental interventions such as agar composition, gene deletion and application of pharmaceuticals. In this study we used physical factors including colony rotation and microgravity to modify ammonia convection and shear stress as environmental cues and observed differences in the responses of both ammonia dependent and stress response dependent pathways We found that the effects of random positioning are distinct from rotation. Furthermore, both true and simulated microgravity exacerbated both cellular redox responses and apoptosis. These changes were largely shear-response dependent but each model had a unique response signature as measured by shear stress genes and the promoter set which regulates them These physical techniques permitted a graded manipulation of both convection and ammonia signaling and are primed to substantially contribute to our understanding of the mechanisms of drug action, cell aging, and colony differentiation.

Survival and Recovery of Phaeocystis Antarctica (Prymnesiophyceae) from Prolonged Darkness and Freezing

Science.gov (United States)

The colony-forming haptophyte Phaeocystis antarctica is an important primary producer in the Ross Sea, and must survive long periods of darkness and freezing in this extreme environment. We conducted experiments on the responses of P. antarctica-dominated phytoplankton assemblage...

ROCK inhibitor Y-27632 enhances the survivability of dissociated buffalo (Bubalus bubalis) embryonic stem cell-like cells.

Science.gov (United States)

Sharma, Ruchi; George, Aman; Chauhan, Manmohan S; Singla, Suresh; Manik, Radhey S; Palta, Prabhat

2013-01-01

This study investigated the effects of supplementation of culture medium with 10 μM Y-27632, a specific inhibitor of Rho kinase activity, for 6 days on self-renewal of buffalo embryonic stem (ES) cell-like cells at Passage 50-80. Y-27632 increased mean colony area (P<0.05) although it did not improve their survival. It decreased OCT4 expression (P<0.05), increased NANOG expression (P<0.05), but had no effect on SOX2 expression. It also increased expression of anti-apoptotic gene BCL-2 (P<0.05) and decreased that of pro-apoptotic genes BAX and BID (P<0.05). It increased plating efficiency of single-cell suspensions of ES cells (P<0.05). Following vitrification, the presence of Y-27632 in the vitrification solution or thawing medium or both did not improve ES cell colony survival. However, following seeding of clumps of ES cells transfected with pAcGFP1N1 carrying green fluorescent protein (GFP), Y-27632 increased colony formation rate (P<0.01). ES cell colonies that formed in all Y-27632-supplemented groups were confirmed for expression of pluripotency markers alkaline phosphatase, SSEA-4 and TRA-1-60, and for their ability to generate embryoid bodies containing cells that expressed markers of ectoderm, mesoderm and endoderm. In conclusion, Y-27632 improves survival of buffalo ES cells under unfavourable conditions such as enzymatic dissociation to single cells or antibiotic-assisted selection after transfection, without compromising their pluripotency.

Gluon saturation: Survival probability for leading neutrons in DIS

International Nuclear Information System (INIS)

Levin, Eugene; Tapia, Sebastian

2012-01-01

In this paper we discuss the example of one rapidity gap process: the inclusive cross sections of the leading neutrons in deep inelastic scattering with protons (DIS). The equations for this process are proposed and solved, giving the example of theoretical calculation of the survival probability for one rapidity gap processes. It turns out that the value of the survival probability is small and it decreases with energy.

Transcriptional signatures of parasitization and markers of colony decline in Varroa-infested honey bees (Apis mellifera).

Science.gov (United States)

Zanni, Virginia; Galbraith, David A; Annoscia, Desiderato; Grozinger, Christina M; Nazzi, Francesco

2017-08-01

Extensive annual losses of honey bee colonies (Apis mellifera L.) reported in the northern hemisphere represent a global problem for agriculture and biodiversity. The parasitic mite Varroa destructor, in association with deformed wing virus (DWV), plays a key role in this phenomenon, but the underlying mechanisms are still unclear. To elucidate these mechanisms, we analyzed the gene expression profile of uninfested and mite infested bees, under laboratory and field conditions, highlighting the effects of parasitization on the bee's transcriptome under a variety of conditions and scenarios. Parasitization was significantly correlated with higher viral loads. Honey bees exposed to mite infestation exhibited an altered expression of genes related to stress response, immunity, nervous system function, metabolism and behavioural maturation. Additionally, mite infested young bees showed a gene expression profile resembling that of forager bees. To identify potential molecular markers of colony decline, the expression of genes that were commonly regulated across the experiments were subsequently assessed in colonies experiencing increasing mite infestation levels. These studies suggest that PGRP-2, hymenoptaecin, a glucan recognition protein, UNC93 and a p450 cytocrome maybe suitable general biomarkers of Varroa-induced colony decline. Furthermore, the reliability of vitellogenin, a yolk protein previously identified as a good marker of colony survival, was confirmed here. Copyright © 2017 Elsevier Ltd. All rights reserved.

Growth Mechanism of Microbial Colonies

Science.gov (United States)

Zhu, Minhui; Martini, K. Michael; Kim, Neil H.; Sherer, Nicholas; Lee, Jia Gloria; Kuhlman, Thomas; Goldenfeld, Nigel

Experiments on nutrient-limited E. coli colonies, growing on agar gel from single cells reveal a power-law distribution of sizes, both during the growth process and in the final stage when growth has ceased. We developed a Python simulation to study the growth mechanism of the bacterial population and thus understand the broad details of the experimental findings. The simulation takes into account nutrient uptake, metabolic function, growth and cell division. Bacteria are modeled in two dimensions as hard circle-capped cylinders with steric interactions and elastic stress dependent growth characteristics. Nutrient is able to diffuse within and between the colonies. The mechanism of microbial colony growth involves reproduction of cells within the colonies and the merging of different colonies. We report results on the dynamic scaling laws and final state size distribution, that capture in semi-quantitative detail the trends observed in experiment. Supported by NSF Grant 0822613.

Pollen foraging in colonies of Melipona bicolor (Apidae, Meliponini): effects of season, colony size and queen number.

Science.gov (United States)

Hilário, S D; Imperatriz-Fonseca, V L

2009-01-01

We evaluated the ratio between the number of pollen foragers and the total number of bees entering colonies of Melipona bicolor, a facultative polygynous species of stingless bees. The variables considered in our analysis were: seasonality, colony size and the number of physogastric queens in each colony. The pollen forager ratios varied significantly between seasons; the ratio was higher in winter than in summer. However, colony size and number of queens per colony had no significant effect. We conclude that seasonal differences in pollen harvest are related to the production of sexuals and to the number of individuals and their body size.

The protons of space and brain tumors: I. Clinical and dosimetric considerations

International Nuclear Information System (INIS)

Dalrymple, G.V.; Nagle, W.A.; Moss, A.J.; Cavin, L.A.; Broadwater, J.R.; McGuire, E.L.; Eason, C.S.

1989-01-01

Almost 25 years ago a large group of Rhesus monkeys were irradiated with protons (32--2300 MeV). The experiments were designed: (1) To estimate the RBE of protons, per se, and (2) To provide some estimate of the hazards of the radiation environment of space. The initial results showed the RBE to be about 1.0 for acute radiation effects (mortality, hematologic changes, etc). The colony has been maintained at Brooks AFB, TX since irradiation. The survivors of 55 MeV proton irradiation have developed a very high incidence of Glioblastoma multiforme, a highly malignant primary brain tumor. These tumors appeared 1--20 yrs after surface doses of 400--800 rads. Reconstruction of the dosimetry suggests that some areas within the brain may have received doses of 1500--2500 rads. More than 30 radiation induced Glioblastomas have been reported in human patients who had received therapeutic head irradiation. The radiation doses required to induce Glioblastoma were of the same order of magnitude as required to induce Glioblastoma in the Rhesus monkey

Survival benefits select for group living in a social spider despite reproductive costs

DEFF Research Database (Denmark)

Bilde, T.; Coates, K.S.; Birkhofer, K.

2007-01-01

The evolution of cooperation requires benefits of group living to exceed costs. Hence, some components of fitness are expected to increase with increasing group size, whereas others may decrease because of competition among group members. The social spiders provide an excellent system to investig......The evolution of cooperation requires benefits of group living to exceed costs. Hence, some components of fitness are expected to increase with increasing group size, whereas others may decrease because of competition among group members. The social spiders provide an excellent system...... to investigate the costs and benefits of group living: they occur in groups of various sizes and individuals are relatively short-lived, therefore life history traits and Lifetime Reproductive Success (LRS) can be estimated as a function of group size. Sociality in spiders has originated repeatedly...... and survival in the social spider Stegodyphus dumicola in two populations in Namibia. In both populations, the major benefit of group living was improved survival of colonies and late-instar juveniles with increasing colony size. By contrast, female fecundity, female body size and early juvenile survival...

Worms at war: interspecific parasite competition and host resources alter trematode colony structure and fitness.

Science.gov (United States)

Mouritsen, Kim N; Andersen, Cecillie

2017-09-01

Parasites competing over limited host resources are faced with a tradeoff between reproductive success and host overexploitation jeopardizing survival. Surprisingly little is known about the outcome of such competitive scenarios, and we therefore aimed at elucidating interactions between the trematodes Himasthla elongata and Renicola roscovita coinfecting the periwinkle first intermediate host. The results show that the success of Himasthla colonies (rediae) in terms of cercarial emission is unaffected by Renicola competition (sporocysts), whereas deteriating host condition decreases fitness. Furthermore, double infection has no bearing on Himasthla's colony size but elevated the proportion of non-reproductive rediae that play a decisive role in colony defence. Opposite, the development of the Renicola colony (size/maturity), and in turn fitness, is markedly reduced in presence of Himasthla, whereas the nutritional state of the host appears less important. Hence, the intramolluscan competition between Himasthla and Renicola is asymmetrical, Himasthla being the superior competitor. Himasthla not only adjusts its virulence according to the hosts immediate nutritional state, it also nullifies the negative impact of a heterospecific competitor on own fitness. The latter is argued to follow in part from direct predation on the competitor, for which purpose more defensive non-reproductive rediae are strategically produced.

New Famennian colonial coral (Rugosa) from the Holy Cross Mountains (Poland): an example of local evolution after Frasnian-Famennian extinction

Science.gov (United States)

Berkowski, Błażej; Zapalski, Mikołaj K.; Wrzołek, Tomasz

2016-04-01

Colonial rugose corals are extremely rare in the fossil record after the Late Devonian (Frasnian-Famennian) extinction event. Here, we report a new genus and species, Famastraea catenata, from the late Famennian of the western part of the Holy Cross Mountains (Kowala) in Poland. Although this taxon is colonial, it displays many morphological characters very close to the typically late Famennian solitary species Palaeosmilia aquisgranensis (Frech, 1885), described earlier from the same locality. Hence, we postulate that F. catenata is derived from P. aquisgranensis. In contrast to other Famennian colonial rugose corals, the new taxon represents an example of local evolution within the group of so-called `Strunian' corals. Consequently, we postulate that the new taxon represents a new colonial rugose fauna, which, however, did not survive the subsequent Late Devonian crisis (i.e. Hangenberg event). F. catenata most probably inhabited deeper water settings, possibly near the boundary between the euphotic and dysphotic zones, as inferred from many other benthic taxa described from this locality.

Proton-proton bremsstrahlung

International Nuclear Information System (INIS)

Fearing, H.W.

1990-01-01

We summarize some of the information about the nucleon-nucleon force which has been obtained by comparing recent calculations of proton-proton bremsstrahlung with cross section and analyzing power data from the new TRIUMF bremsstrahlung experiment. Some comments are made as to how these results can be extended to neutron-proton bremsstrahlung. (Author) 17 refs., 6 figs

Political instability and discontinuity in Nigeria: The pre-colonial past and public goods provision under colonial and post-colonial political orders

NARCIS (Netherlands)

Papaioannou, K.I.; Dalrymple-Smith, A.E.

2015-01-01

This article explores the relative importance of pre-colonial institutional capacity and the effects of periods of peace and stability on long-term development outcomes in Nigeria. We use data on education, health, and public works at a provincial level from a variety of colonial and Nigerian state

Comparative study on the dynamics and performances of Apis mellifera jemenitica and imported hybrid honeybee colonies in southwestern Saudi Arabia

Directory of Open Access Journals (Sweden)

Ahmad A. Al-Ghamdi

2017-07-01

Full Text Available The aims of this study were to assess the seasonal population dynamics and evaluate the performance of Apis mellifera jemenitica (local bee and introduced hybrid honeybee colonies in the lowlands and highlands of southwestern Saudi Arabia. Data regarding the performance and population dynamics parameters such as brood and adult bee population, amounts of stored pollen and nectar were gathered from the two races (25 colonies of each for one year (April 2013 through March 2014, and statistically tested. The results indicated that at low lands, local bee colonies maintained relatively high brood and adult bee populations (P < 0.05 than introduced honeybee colonies and produced more (P < 0.05 honey. The local bee colonies were able to hoard three times more (P < 0.05 pollen and built more (P < 0.05 queen cells than introduced bees in both the low and highland areas. The annual survival rate of local bee colonies was almost double (P < 0.05 than that of introduced honeybee colonies. Moreover, local bees had greater (P < 0.05 adult bee and brood populations than imported, throughout the year. The relatively good performance of local colonies could be due to their long year’s adaptation to cope with resource scarcity and unpredictable environmental conditions of the regions. The possible reasons for the dwindling of the imported hybrid colonies could be due to continuing to exhibit adaptive characteristics of their original that might not fit well with the new environment.

Nerve growth factor promotes human hemopoietic colony growth and differentiation

International Nuclear Information System (INIS)

Matsuda, H.; Coughlin, M.D.; Bienenstock, J.; Denburg, J.A.

1988-01-01

Nerve growth factor (NGF) is a neurotropic polypeptide necessary for the survival and growth of some central neurons, as well as sensory afferent and sympathetic neurons. Much is now known of the structural and functional characteristics of NGF, whose gene has recently been clones. Since it is synthesized in largest amounts by the male mouse submandibular gland, its role exclusively in nerve growth is questionable. These experiments indicate that NGF causes a significant stimulation of granulocyte colonies grown from human peripheral blood in standard hemopoietic methylcellulose assays. Further, NGF appears to act in a relatively selective fashion to induce the differentiation of eosinophils and basophils/mast cells. Depletion experiments show that the NGF effect may be T-cell dependent and that NGF augments the colony-stimulating effect of supernatants from the leukemic T-cell (Mo) line. The hemopoietic activity of NGF is blocked by 125 I-polyclonal and monoclonal antibodies to NGF. The authors conclude that NGF may indirectly act as a local growth factor in tissues other than those of the nervous system by causing T cells to synthesize or secrete molecules with colony-stimulating activity. In view of the synthesis of NGF in tissue injury, the involvement of basophils/mast cells and eosinophils in allergic and other inflammatory processes, and the association of mast cells with fibrosis and tissue repair, they postulate that NGF plays an important biological role in a variety of repair processes

Photosynthetic planulae and planktonic hydroids: contrasting strategies of propagule survival

Directory of Open Access Journals (Sweden)

Patrizia Pagliara

2000-12-01

Full Text Available Settlement delays can be important to prevent propagule waste when proper settling substrates are not immediately available. Under laboratory conditions, the planulae of Clytia viridicans underwent two alternative developmental patterns. Some settled on the bottom, forming a hydranth-gonotheca complex that produced up to four medusae and later either degenerated or gave rise to a hydroid colony. Other planulae settled right below the air-water interface, forming floating colonies that eventually fell to the bottom and settled. Halecium nanum released planulae with a rich population of symbiotic zooxanthellae that survived into a rearing jar for three months. After a long period of apparent quiescence (possibly fuelled by photosynthetic activities of zooxanthellae the planulae produced new colonies. Both photosynthetic planulae and settlement at the interface air-water allow a delay in the passage from a planktonic to a fully functional benthic life.

High Expression of Colony-Stimulating Factor 1 Receptor Associates with Unfavorable Cancer-Specific Survival of Patients with Clear Cell Renal Cell Carcinoma.

Science.gov (United States)

Yang, Liu; Liu, Yidong; An, Huimin; Chang, Yuan; Zhang, Weijuan; Zhu, Yu; Xu, Le; Xu, Jiejie

2016-03-01

Colony-stimulating factor 1 receptor (CSF-1R), a single-pass type III transmembrane tyrosine-protein kinase, is mainly involved in inflammation and immune regulation to facilitate the progression of solid tumors. This study aimed to evaluate the impact of CSF-1R expression on clinical outcome of patients with clear cell renal cell carcinoma (ccRCC) after surgery. We retrospectively enrolled 268 patients with ccRCC undergoing nephrectomy between 2001 and 2004. Clinicopathologic features and cancer-specific survival (CSS) were collected. Western blot analysis was performed in the pairwise comparisons of CSF-1R expression in peritumor and tumor tissues of patients with ccRCC. Immunohistochemistry was conducted to determine CSF-1R expression level in tumor specimens. Survival analysis was performed by the Kaplan-Meier method. Cox regression models were used to evaluate the impact of prognostic factors on CSS. A concordance index was calculated to measure prognostic accuracy. A prognostic nomogram was constructed on the basis of the identified independent prognostic factors. CSF-1R expression in tumor tissues was higher than in peritumor tissues in 71.4% (5 of 7) patients. CSF-1R expression of tumor tissues was positively associated with metastasis, tumor, node, metastasis classification system (TNM) stage, Eastern Cooperative Oncology Group performance status score and poor CSS. CSF-1R expression was determined as an independent prognostic factor for CSS in patients with ccRCC. Furthermore, extension of the well-established prognostic models with CSF-1R expression presented significantly improved prognostic accuracy. An efficient prognostic nomogram was constructed on the basis of the independent prognostic factors. High CSF-1R expression is a potential independent adverse prognostic factor for CSS in patients with ccRCC.

Queen promiscuity lowers disease within honeybee colonies

Science.gov (United States)

Seeley, Thomas D; Tarpy, David R

2006-01-01

Most species of social insects have singly mated queens, but in some species each queen mates with numerous males to create a colony with a genetically diverse worker force. The adaptive significance of polyandry by social insect queens remains an evolutionary puzzle. Using the honeybee (Apis mellifera), we tested the hypothesis that polyandry improves a colony's resistance to disease. We established colonies headed by queens that had been artificially inseminated by either one or 10 drones. Later, we inoculated these colonies with spores of Paenibacillus larvae, the bacterium that causes a highly virulent disease of honeybee larvae (American foulbrood). We found that, on average, colonies headed by multiple-drone inseminated queens had markedly lower disease intensity and higher colony strength at the end of the summer relative to colonies headed by single-drone inseminated queens. These findings support the hypothesis that polyandry by social insect queens is an adaptation to counter disease within their colonies. PMID:17015336

Radiosensitivity of CD4 and CD8 positive human T lymphocytes by an in vitro colony formation assay

International Nuclear Information System (INIS)

Nakamura, Nori; Kusunoki, Yoichiro; Akiyama, Mitoshi.

1989-12-01

The recent development of an in vitro lymphocyte colony assay provides a new opportunity to examine possible variations in human radiosensitivity using peripheral blood lymphocytes (PBL) in place of the hitherto used skin fibroblast assay. Our recent study showed that most of the colonies consisted of lymphocytes bearing CD4 or CD8 antigens. Since the fraction of CD4 + and CD8 + cells in PBL differs among individuals, it was suspected that individual radiosensitivity might be biased by the different subset frequencies if the dose-survival curves of the CD4 + and CD8 + cells differed. In the present study, CD4 + lymphocytes (helper/inducer T cells) and CD8 + lymphocytes (suppressor/cytotoxic T cells) were isolated from PBL and their dose-survival curves were determined. The results showed that the D 10 (the dose required to reduce the surviving fraction to 10 %) was quite similar for these two types of cells (3.13 ± 0.10 Gy [mean ±SD] for CD4 + , 3.34 ± 0.50 Gy for CD8 + and 3.07 ± 0.05 Gy for the unsorted cells), supporting the use of a whole PBL population for screening of individuals with altered radiosensitivity. (author)

Definitive Reirradiation for Locoregionally Recurrent Non-Small Cell Lung Cancer With Proton Beam Therapy or Intensity Modulated Radiation Therapy: Predictors of High-Grade Toxicity and Survival Outcomes

Energy Technology Data Exchange (ETDEWEB)

McAvoy, Sarah; Ciura, Katherine; Wei, Caimiao; Rineer, Justin; Liao, Zhongxing; Chang, Joe Y.; Palmer, Matthew B.; Cox, James D.; Komaki, Ritsuko; Gomez, Daniel R., E-mail: DGomez@mdanderson.org

2014-11-15

Purpose: Intrathoracic recurrence of non-small cell lung cancer (NSCLC) after initial treatment remains a dominant cause of death. We report our experience using proton beam therapy and intensity modulated radiation therapy for reirradiation in such cases, focusing on patterns of failure, criteria for patient selection, and predictors of toxicity. Methods and Materials: A total of 102 patients underwent reirradiation for intrathoracic recurrent NSCLC at a single institution. All doses were recalculated to an equivalent dose in 2-Gy fractions (EQD2). All patients had received radiation therapy for NSCLC (median initial dose of 70 EQD2 Gy), with median interval to reirradiation of 17 months and median reirradiation dose of 60.48 EQD2 Gy. Median follow-up time was 6.5 months (range, 0-72 months). Results: Ninety-nine patients (97%) completed reirradiation. Median local failure-free survival, distant metastasis-free survival (DMFS), and overall survival times were 11.43 months (range, 8.6-22.66 months), 11.43 months (range, 6.83-23.84 months), and 14.71 (range, 10.34-20.56 months), respectively. Toxicity was acceptable, with rates of grade ≥3 esophageal toxicity of 7% and grade ≥3 pulmonary toxicity of 10%. Of the patients who developed local failure after reirradiation, 88% had failure in either the original or the reirradiation field. Poor local control was associated with T4 disease, squamous histology, and Eastern Cooperative Oncology Group performance status score >1. Concurrent chemotherapy improved DMFS, but T4 disease was associated with poor DMFS. Higher T status, Eastern Cooperative Oncology Group performance status ≥1, squamous histology, and larger reirradiation target volumes led to worse overall survival; receipt of concurrent chemotherapy and higher EQD2 were associated with improved OS. Conclusions: Intensity modulated radiation therapy and proton beam therapy are options for treating recurrent non-small cell lung cancer. However, rates of

CFAssay: statistical analysis of the colony formation assay

International Nuclear Information System (INIS)

Braselmann, Herbert; Michna, Agata; Heß, Julia; Unger, Kristian

2015-01-01

Colony formation assay is the gold standard to determine cell reproductive death after treatment with ionizing radiation, applied for different cell lines or in combination with other treatment modalities. Associated linear-quadratic cell survival curves can be calculated with different methods. For easy code exchange and methodological standardisation among collaborating laboratories a software package CFAssay for R (R Core Team, R: A Language and Environment for Statistical Computing, 2014) was established to perform thorough statistical analysis of linear-quadratic cell survival curves after treatment with ionizing radiation and of two-way designs of experiments with chemical treatments only. CFAssay offers maximum likelihood and related methods by default and the least squares or weighted least squares method can be optionally chosen. A test for comparision of cell survival curves and an ANOVA test for experimental two-way designs are provided. For the two presented examples estimated parameters do not differ much between maximum-likelihood and least squares. However the dispersion parameter of the quasi-likelihood method is much more sensitive for statistical variation in the data than the multiple R 2 coefficient of determination from the least squares method. The dispersion parameter for goodness of fit and different plot functions in CFAssay help to evaluate experimental data quality. As open source software interlaboratory code sharing between users is facilitated

Proton Radiotherapy for Pediatric Ewing’s Sarcoma: Initial Clinical Outcomes

International Nuclear Information System (INIS)

Rombi, Barbara; DeLaney, Thomas F.; MacDonald, Shannon M.; Huang, Mary S.; Ebb, David H.; Liebsch, Norbert J.; Raskin, Kevin A.; Yeap, Beow Y.; Marcus, Karen J.; Tarbell, Nancy J.; Yock, Torunn I.

2012-01-01

Purpose: Proton radiotherapy (PT) has been prescribed similarly to photon radiotherapy to achieve comparable disease control rates at comparable doses. The chief advantage of protons in this setting is to reduce acute and late toxicities by decreasing the amount of normal tissue irradiated. We report the preliminary clinical outcomes including late effects on our pediatric Ewing’s sarcoma patients treated with PT at the Francis H. Burr Proton Therapy Center at Massachusetts General Hospital (Boston, MA). Methods and Materials: This was a retrospective review of the medical records of 30 children with Ewing’s sarcoma who were treated with PT between April 2003 and April 2009. Results: A total of 14 male and 16 female patients with tumors in several anatomic sites were treated with PT at a median age of 10 years. The median dose was 54 Gy (relative biological effectiveness) with a median follow-up of 38.4 months. The 3-year actuarial rates of event-free survival, local control, and overall survival were 60%, 86%, and 89%, respectively. PT was acutely well tolerated, with mostly mild-to-moderate skin reactions. At the time of writing, the only serious late effects have been four hematologic malignancies, which are known risks of topoisomerase and anthracyline exposure. Conclusions: Proton radiotherapy was well tolerated, with few adverse events. Longer follow-up is needed to more fully assess tumor control and late effects, but the preliminary results are encouraging.

Arginine promotes Proteus mirabilis motility and fitness by contributing to conservation of the proton gradient and proton motive force.

Science.gov (United States)

Armbruster, Chelsie E; Hodges, Steven A; Smith, Sara N; Alteri, Christopher J; Mobley, Harry L T

2014-10-01

Swarming contributes to Proteus mirabilis pathogenicity by facilitating access to the catheterized urinary tract. We previously demonstrated that 0.1-20 mmol/L arginine promotes swarming on normally nonpermissive media and that putrescine biosynthesis is required for arginine-induced swarming. We also previously determined that arginine-induced swarming is pH dependent, indicating that the external proton concentration is critical for arginine-dependent effects on swarming. In this study, we utilized survival at pH 5 and motility as surrogates for measuring changes in the proton gradient (ΔpH) and proton motive force (μH(+) ) in response to arginine. We determined that arginine primarily contributes to ΔpH (and therefore μH(+) ) through the action of arginine decarboxylase (speA), independent of the role of this enzyme in putrescine biosynthesis. In addition to being required for motility, speA also contributed to fitness during infection. In conclusion, consumption of intracellular protons via arginine decarboxylase is one mechanism used by P. mirabilis to conserve ΔpH and μH(+) for motility. © 2014 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

A dose-surviving fraction curve for mouse colonic mucosa

International Nuclear Information System (INIS)

Tucker, S.L.; Thames, H.D. Jr.; Withers, H.R.; Mason, K.A.

1983-01-01

A dose-surviving fraction curve representing the response of the mouse colonic mucosa to single doses of 137 Cs gamma radiation was obtained from the results of a multifraction in vivo colony assay. Construction of the curve required an estimated of the average number of clonogens initially present per colonic crypt. The estimated clonogen count (88) was determined by a statistical method based on the use of doses per fraction common to different fractionation protocols. Parameters for the LQ and TC models of cell survival were obtained by weighted least-squares fits to the data. A comparison of the survival characteristics of cells from the mouse colonic and jejunal crypts suggested that the epithelium of the colon is less radiosensitive than that of the jejunum. (author)

Study of the effects of high-energy proton beams on escherichia coli

Science.gov (United States)

Park, Jeong Chan; Jung, Myung-Hwan

2015-10-01

Antibiotic-resistant bacterial infection is one of the most serious risks to public health care today. However, discouragingly, the development of new antibiotics has progressed little over the last decade. There is an urgent need for alternative approaches to treat antibiotic-resistant bacteria. Novel methods, which include photothermal therapy based on gold nano-materials and ionizing radiation such as X-rays and gamma rays, have been reported. Studies of the effects of high-energy proton radiation on bacteria have mainly focused on Bacillus species and its spores. The effect of proton beams on Escherichia coli (E. coli) has been limitedly reported. Escherichia coli is an important biological tool to obtain metabolic and genetic information and is a common model microorganism for studying toxicity and antimicrobial activity. In addition, E. coli is a common bacterium in the intestinal tract of mammals. In this research, the morphological and the physiological changes of E. coli after proton irradiation were investigated. Diluted solutions of cells were used for proton beam radiation. LB agar plates were used to count the number of colonies formed. The growth profile of the cells was monitored by using the optical density at 600 nm. The morphology of the irradiated cells was observed with an optical microscope. A microarray analysis was performed to examine the gene expression changes between irradiated samples and control samples without irradiation. E coli cells have observed to be elongated after proton irradiation with doses ranging from 13 to 93 Gy. Twenty-two were up-regulated more than twofold in proton-irradiated samples (93 Gy) compared with unexposed one.

JAX Colony Management System (JCMS): an extensible colony and phenotype data management system.

Science.gov (United States)

Donnelly, Chuck J; McFarland, Mike; Ames, Abigail; Sundberg, Beth; Springer, Dave; Blauth, Peter; Bult, Carol J

2010-04-01

The Jackson Laboratory Colony Management System (JCMS) is a software application for managing data and information related to research mouse colonies, associated biospecimens, and experimental protocols. JCMS runs directly on computers that run one of the PC Windows operating systems, but can be accessed via web browser interfaces from any computer running a Windows, Macintosh, or Linux operating system. JCMS can be configured for a single user or multiple users in small- to medium-size work groups. The target audience for JCMS includes laboratory technicians, animal colony managers, and principal investigators. The application provides operational support for colony management and experimental workflows, sample and data tracking through transaction-based data entry forms, and date-driven work reports. Flexible query forms allow researchers to retrieve database records based on user-defined criteria. Recent advances in handheld computers with integrated barcode readers, middleware technologies, web browsers, and wireless networks add to the utility of JCMS by allowing real-time access to the database from any networked computer.

Collective Memories of Portuguese Colonial Action in Africa: Representations of the Colonial Past among Mozambicans and Portuguese Youths

Directory of Open Access Journals (Sweden)

João Feijó

2010-05-01

Full Text Available Social representations of the colonization and decolonization processes among young people from a former European colonial power (Portugal and from an African ex-colony (Mozambique were investigated through surveys using open- and closed-ended questions about national history, focusing on the identity functions of collective memories. Hegemonic and contested representations were found of the most prominent events related to Portuguese colonization of Mozambique, arousing a range of collective emotions. A central place is occupied by memories of the Colonial War, which ended with the Carnation Revolution in Portugal and the subsequent independence of the Portuguese African colonies. Overall, the depiction of colonialism was more negative for Mozambican than for Portuguese participants. The violent effects of colonial action were very salient in Mozambican memories, which stressed the most oppressive aspects of the colonial period, associated with slave trade and brutal repression. On the Portuguese side, the idealization of the voyages of discovery persisted, obscuring the most violent effects of colonial expansion. However, collective memories of colonization of former colonizer and former colonized do not simply stand opposed. Both Mozambican and Portuguese participants reported ambivalent feelings towards the colonization process.

Protein proton-proton dynamics from amide proton spin flip rates

International Nuclear Information System (INIS)

Weaver, Daniel S.; Zuiderweg, Erik R. P.

2009-01-01

Residue-specific amide proton spin-flip rates K were measured for peptide-free and peptide-bound calmodulin. K approximates the sum of NOE build-up rates between the amide proton and all other protons. This work outlines the theory of multi-proton relaxation, cross relaxation and cross correlation, and how to approximate it with a simple model based on a variable number of equidistant protons. This model is used to extract the sums of K-rates from the experimental data. Error in K is estimated using bootstrap methodology. We define a parameter Q as the ratio of experimental K-rates to theoretical K-rates, where the theoretical K-rates are computed from atomic coordinates. Q is 1 in the case of no local motion, but decreases to values as low as 0.5 with increasing domination of sidechain protons of the same residue to the amide proton flips. This establishes Q as a monotonous measure of local dynamics of the proton network surrounding the amide protons. The method is applied to the study of proton dynamics in Ca 2+ -saturated calmodulin, both free in solution and bound to smMLCK peptide. The mean Q is 0.81 ± 0.02 for free calmodulin and 0.88 ± 0.02 for peptide-bound calmodulin. This novel methodology thus reveals the presence of significant interproton disorder in this protein, while the increase in Q indicates rigidification of the proton network upon peptide binding, confirming the known high entropic cost of this process

Post-colonial identity in Greenland?

DEFF Research Database (Denmark)

Gad, Ulrik Pram

2009-01-01

could be furthered by bringing politics back in. Based on a discourse analysis of the Greenlandic debate on language, this paper makes three claims: First, the identity projects promoted in Greenland are based on an essentialist conception of identity. Secondly, Greenlandic identity discourse combines......In the gradual unravelling of Greenland’s colonial relationship to Denmark, an essentialist conceptualization of Greenlandic identity has played a significant role. However, both our scholarly understanding of post-colonial Greenlandic identity and the process towards independence for Greenland...... elements of traditional Inuit culture and elements of colonial modernity. Thirdly, monolingual Greenlanders are those with the most to gain from abandoning the dichotomy of essentialist identities. Strategically, the paper suggests a post-post-colonial Greenlandic identity as a means of avoiding...

The Gottingen Minipig Is a Model of the Hematopoietic Acute Radiation Syndrome: G-Colony Stimulating Factor Stimulates Hematopoiesis and Enhances Survival From Lethal Total-Body γ-Irradiation

Energy Technology Data Exchange (ETDEWEB)

Moroni, Maria, E-mail: maria.moroni@usuhs.edu [Radiation Countermeasures Program, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, Maryland (United States); Ngudiankama, Barbara F. [Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland (United States); Christensen, Christine [Division of Comparative Pathology, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, Maryland (United States); Olsen, Cara H. [Biostatistics Consulting Center, Uniformed Services University of the Health Sciences, Bethesda, Maryland (United States); Owens, Rossitsa [Radiation Countermeasures Program, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, Maryland (United States); Lombardini, Eric D. [Veterinary Medicine Department, Armed Forces Research Institute of Medical Sciences, Bangkok (Thailand); Holt, Rebecca K. [Veterinary Science Department, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, Maryland (United States); Whitnall, Mark H. [Radiation Countermeasures Program, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, Maryland (United States)

2013-08-01

Purpose: We are characterizing the Gottingen minipig as an additional large animal model for advanced drug testing for the acute radiation syndrome (ARS) to enhance the discovery and development of novel radiation countermeasures. Among the advantages provided by this model, the similarities to human hematologic parameters and dynamics of cell loss/recovery after irradiation provide a convenient means to compare the efficacy of drugs known to affect bone marrow cellularity and hematopoiesis. Methods and Materials: Male Gottingen minipigs, 4 to 5 months old and weighing 9 to 11 kg, were used for this study. We tested the standard off-label treatment for ARS, rhG-CSF (Neupogen, 10 μg/kg/day for 17 days), at the estimated LD70/30 total-body γ-irradiation (TBI) radiation dose for the hematopoietic syndrome, starting 24 hours after irradiation. Results: The results indicated that granulocyte colony stimulating factor (G-CSF) enhanced survival, stimulated recovery from neutropenia, and induced mobilization of hematopoietic progenitor cells. In addition, the administration of G-CSF resulted in maturation of monocytes/macrophages. Conclusions: These results support continuing efforts toward validation of the minipig as a large animal model for advanced testing of radiation countermeasures and characterization of the pathophysiology of ARS, and they suggest that the efficacy of G-CSF in improving survival after total body irradiation may involve mechanisms other than increasing the numbers of circulating granulocytes.

The Gottingen minipig is a model of the hematopoietic acute radiation syndrome: G-colony stimulating factor stimulates hematopoiesis and enhances survival from lethal total-body γ-irradiation.

Science.gov (United States)

Moroni, Maria; Ngudiankama, Barbara F; Christensen, Christine; Olsen, Cara H; Owens, Rossitsa; Lombardini, Eric D; Holt, Rebecca K; Whitnall, Mark H

2013-08-01

We are characterizing the Gottingen minipig as an additional large animal model for advanced drug testing for the acute radiation syndrome (ARS) to enhance the discovery and development of novel radiation countermeasures. Among the advantages provided by this model, the similarities to human hematologic parameters and dynamics of cell loss/recovery after irradiation provide a convenient means to compare the efficacy of drugs known to affect bone marrow cellularity and hematopoiesis. Male Gottingen minipigs, 4 to 5 months old and weighing 9 to 11 kg, were used for this study. We tested the standard off-label treatment for ARS, rhG-CSF (Neupogen, 10 μg/kg/day for 17 days), at the estimated LD70/30 total-body γ-irradiation (TBI) radiation dose for the hematopoietic syndrome, starting 24 hours after irradiation. The results indicated that granulocyte colony stimulating factor (G-CSF) enhanced survival, stimulated recovery from neutropenia, and induced mobilization of hematopoietic progenitor cells. In addition, the administration of G-CSF resulted in maturation of monocytes/macrophages. These results support continuing efforts toward validation of the minipig as a large animal model for advanced testing of radiation countermeasures and characterization of the pathophysiology of ARS, and they suggest that the efficacy of G-CSF in improving survival after total body irradiation may involve mechanisms other than increasing the numbers of circulating granulocytes. Published by Elsevier Inc.

The Gottingen Minipig Is a Model of the Hematopoietic Acute Radiation Syndrome: G-Colony Stimulating Factor Stimulates Hematopoiesis and Enhances Survival From Lethal Total-Body γ-Irradiation

International Nuclear Information System (INIS)

Moroni, Maria; Ngudiankama, Barbara F.; Christensen, Christine; Olsen, Cara H.; Owens, Rossitsa; Lombardini, Eric D.; Holt, Rebecca K.; Whitnall, Mark H.

2013-01-01

Purpose: We are characterizing the Gottingen minipig as an additional large animal model for advanced drug testing for the acute radiation syndrome (ARS) to enhance the discovery and development of novel radiation countermeasures. Among the advantages provided by this model, the similarities to human hematologic parameters and dynamics of cell loss/recovery after irradiation provide a convenient means to compare the efficacy of drugs known to affect bone marrow cellularity and hematopoiesis. Methods and Materials: Male Gottingen minipigs, 4 to 5 months old and weighing 9 to 11 kg, were used for this study. We tested the standard off-label treatment for ARS, rhG-CSF (Neupogen, 10 μg/kg/day for 17 days), at the estimated LD70/30 total-body γ-irradiation (TBI) radiation dose for the hematopoietic syndrome, starting 24 hours after irradiation. Results: The results indicated that granulocyte colony stimulating factor (G-CSF) enhanced survival, stimulated recovery from neutropenia, and induced mobilization of hematopoietic progenitor cells. In addition, the administration of G-CSF resulted in maturation of monocytes/macrophages. Conclusions: These results support continuing efforts toward validation of the minipig as a large animal model for advanced testing of radiation countermeasures and characterization of the pathophysiology of ARS, and they suggest that the efficacy of G-CSF in improving survival after total body irradiation may involve mechanisms other than increasing the numbers of circulating granulocytes

The influence of social structure on brood survival and development in a socially polymorphic ant: insights from a cross-fostering experiment.

Science.gov (United States)

Purcell, Jessica; Chapuisat, M

2012-11-01

Animal societies vary in the number of breeders per group, which affects many socially and ecologically relevant traits. In several social insect species, including our study species Formica selysi, the presence of either one or multiple reproducing females per colony is generally associated with differences in a suite of traits such as the body size of individuals. However, the proximate mechanisms and ontogenetic processes generating such differences between social structures are poorly known. Here, we cross-fostered eggs originating from single-queen (= monogynous) or multiple-queen (= polygynous) colonies into experimental groups of workers from each social structure to investigate whether differences in offspring survival, development time and body size are shaped by the genotype and/or prefoster maternal effects present in the eggs, or by the social origin of the rearing workers. Eggs produced by polygynous queens were more likely to survive to adulthood than eggs from monogynous queens, regardless of the social origin of the rearing workers. However, brood from monogynous queens grew faster than brood from polygynous queens. The social origin of the rearing workers influenced the probability of brood survival, with workers from monogynous colonies rearing more brood to adulthood than workers from polygynous colonies. The social origin of eggs or rearing workers had no significant effect on the head size of the resulting workers in our standardized laboratory conditions. Overall, the social backgrounds of the parents and of the rearing workers appear to shape distinct survival and developmental traits of ant brood. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.

A Phase 2 Trial of Concurrent Chemotherapy and Proton Therapy for Stage III Non-Small Cell Lung Cancer: Results and Reflections Following Early Closure of a Single-Institution Study

Energy Technology Data Exchange (ETDEWEB)

Hoppe, Bradford S., E-mail: bhoppe@floridaproton.org [University of Florida Health Proton Therapy Institute, Jacksonville, Florida (United States); Henderson, Randal [University of Florida Health Proton Therapy Institute, Jacksonville, Florida (United States); Pham, Dat; Cury, James D.; Bajwa, Abubakr [Department of Medicine, University of Florida College of Medicine, Jacksonville, Florida (United States); Morris, Christopher G. [University of Florida Health Proton Therapy Institute, Jacksonville, Florida (United States); D' Agostino, Harry [Department of Surgery, University of Florida College of Medicine, Jacksonville, Florida (United States); Flampouri, Stella; Huh, Soon; Li, Zuofeng [University of Florida Health Proton Therapy Institute, Jacksonville, Florida (United States); McCook, Barry [Department of Radiology, University of Florida College of Medicine, Jacksonville, Florida (United States); Nichols, Romaine C. [University of Florida Health Proton Therapy Institute, Jacksonville, Florida (United States)

2016-05-01

Purpose: Proton therapy has been shown to reduce radiation dose to organs at risk (OAR) and could be used to safely escalate the radiation dose. We analyzed outcomes in a group of phase 2 study patients treated with dose-escalated proton therapy with concurrent chemotherapy for stage 3 non-small cell lung cancer (NSCLC). Methods and Materials: From 2009 through 2013, LU02, a phase 2 trial of proton therapy delivering 74 to 80 Gy at 2 Gy/fraction with concurrent chemotherapy for stage 3 NSCLC, was opened to accrual at our institution. Due to slow accrual and competing trials, the study was closed after just 14 patients (stage IIIA, 9 patients; stage IIIB, 5 patients) were accrued over 4 years. During that same time period, 55 additional stage III patients were treated with high-dose proton therapy, including 7 in multi-institutional proton clinical trials, 4 not enrolled due to physician preference, and 44 who were ineligible based on strict entry criteria. An unknown number of patients were ineligible for enrollment due to insurance coverage issues and thus were treated with photon radiation. Median follow-up of surviving patients was 52 months. Results: Two-year overall survival and progression-free survival rates were 57% and 25%, respectively. Median lengths of overall survival and progression-free survival were 33 months and 14 months, respectively. There were no acute grade 3 toxicities related to proton therapy. Late grade 3 gastrointestinal toxicity and pulmonary toxicity each occurred in 1 patient. Conclusions: Dose-escalated proton therapy with concurrent chemotherapy was well tolerated with encouraging results among a small cohort of patients. Unfortunately, single-institution proton studies may be difficult to accrue and consideration for pragmatic and/or multicenter trial design should be considered when developing future proton clinical trials.

Hand-rearing, release and survival of African penguin chicks abandoned before independence by moulting parents.

Science.gov (United States)

Sherley, Richard B; Waller, Lauren J; Strauss, Venessa; Geldenhuys, Deon; Underhill, Les G; Parsons, Nola J

2014-01-01

The African penguin Spheniscus demersus has an 'Endangered' conservation status and a decreasing population. Following abandonment, 841 African penguin chicks in 2006 and 481 in 2007 were admitted to SANCCOB (Southern African Foundation for the Conservation of Coastal Birds) for hand-rearing from colonies in the Western Cape, South Africa, after large numbers of breeding adults commenced moult with chicks still in the nest. Of those admitted, 91% and 73% respectively were released into the wild. There were veterinary concerns about avian malaria, airsacculitis and pneumonia, feather-loss and pododermatitis (bumblefoot). Post-release juvenile (0.32, s.e.  = 0.08) and adult (0.76, s.e.  = 0.10) survival rates were similar to African penguin chicks reared after oil spills and to recent survival rates recorded for naturally-reared birds. By December 2012, 12 birds had bred, six at their colony of origin, and the apparent recruitment rate was 0.11 (s.e.  = 0.03). Hand-rearing of abandoned penguin chicks is recommended as a conservation tool to limit mortality and to bolster the population at specific colonies. The feasibility of conservation translocations for the creation of new colonies for this species using hand-reared chicks warrants investigation. Any such programme would be predicated on adequate disease surveillance programmes established to minimise the risk of disease introduction to wild birds.

Caffeine-enhanced survival of radiation-sensitive, repair-deficient Chinese hamster cells

International Nuclear Information System (INIS)

Utsumi, H.; Elkind, M.M.

1983-01-01

A clone of V79 Chinese hamster cells (V79-AL162/S-10) with unique properties has been isolated after a challenge of parental cells (V79-AL162) with 1 mM ouabain. Compared with parental cells, or with other clones isolated after the ouabain challenge, these cells form smaller colonies, are more sensitive to both x rays and fission-spectrum neutrons, and respond atypically to a postirradiation treatment with caffeine. Their enhanced response to x rays results mainly from a large reduction in the shoulder of their survival curve, probably because in late S phase, the most resistant phase in the cell cycle, the survival curve of these cells has a reduced shoulder width. Caffeine, and to a lesser extent theophylline, added to the colony-forming medium immediately after exposure appreciably increases the width of the shoulder of these sensitive cells, whereas caffeine has the opposite effect on the response of normal V79 cells. Thus the unique response of the V79-AL162/S-10 cells to a radiation posttreatment with caffeine (increased survival) results from a net increase in their ability to repair damage that is otherwise lethal; caffeine treatment ordinarly prevents normal V79 cells from repairing damage that is only potentially lethal

Early Developmental Program Shapes Colony Morphology in Bacteria

Directory of Open Access Journals (Sweden)

Gideon Mamou

2016-03-01

Full Text Available When grown on a solid surface, bacteria form highly organized colonies, yet little is known about the earliest stages of colony establishment. Following Bacillus subtilis colony development from a single progenitor cell, a sequence of highly ordered spatiotemporal events was revealed. Colony was initiated by the formation of leading-cell chains, deriving from the colony center and extending in multiple directions, typically in a “Y-shaped” structure. By eradicating particular cells during these early stages, we could influence the shape of the resulting colony and demonstrate that Y-arm extension defines colony size. A mutant in ymdB encoding a phosphodiesterase displayed unordered developmental patterns, indicating a role in guiding these initial events. Finally, we provide evidence that intercellular nanotubes contribute to proper colony formation. In summary, we reveal a “construction plan” for building a colony and provide the initial molecular basis for this process.

Fitness of isogenic colony morphology variants of Pseudomonas aeruginosa in murine airway infection.

Directory of Open Access Journals (Sweden)

Elza Rakhimova

Full Text Available Chronic lung infections with Pseudomonas aeruginosa are associated with the diversification of the persisting clone into niche specialists and morphotypes, a phenomenon called 'dissociative behaviour'. To explore the potential of P. aeruginosa to change its morphotype by single step loss-of-function mutagenesis, a signature-tagged mini-Tn5 plasposon library of the cystic fibrosis airway isolate TBCF10839 was screened for colony morphology variants under nine different conditions in vitro. Transposon insertion into 1% of the genome changed colony morphology into eight discernable morphotypes. Half of the 55 targets encode features of primary or secondary metabolism whereby quinolone production was frequently affected. In the other half the transposon had inserted into genes of the functional categories transport, regulation or motility/chemotaxis. To mimic dissociative behaviour of isogenic strains in lungs, pools of 25 colony morphology variants were tested for competitive fitness in an acute murine airway infection model. Six of the 55 mutants either grew better or worse in vivo than in vitro, respectively. Metabolic proficiency of the colony morphology variant was a key determinant for survival in murine airways. The most common morphotype of self-destructive autolysis did unexpectedly not impair fitness. Transposon insertions into homologous genes of strain PAO1 did not reproduce the TBCF10839 mutant morphotypes for 16 of 19 examined loci pointing to an important role of the genetic background on colony morphology. Depending on the chosen P. aeruginosa strain, functional genome scans will explore other areas of the evolutionary landscape. Based on our discordant findings of mutant phenotypes in P. aeruginosa strains PAO1, PA14 and TBCF10839, we conclude that the current focus on few reference strains may miss modes of niche adaptation and dissociative behaviour that are relevant for the microevolution of complex traits in the wild.

Single cell time-lapse analysis reveals that podoplanin enhances cell survival and colony formation capacity of squamous cell carcinoma cells.

Science.gov (United States)

Miyashita, Tomoyuki; Higuchi, Youichi; Kojima, Motohiro; Ochiai, Atsushi; Ishii, Genichiro

2017-01-06

Tumor initiating cells (TICs) are characterized by high clonal expansion capacity. We previously reported that podoplanin is a TIC-specific marker for the human squamous cell carcinoma cell line A431. The aim of this study is to explore the molecular mechanism underlying the high clonal expansion potential of podoplanin-positive A431cells using Fucci imaging. Single podoplanin-positive cells created large colonies at a significantly higher frequency than single podoplanin-negative cells, whereas no difference was observed between the two types of cells with respect to cell cycle status. Conversely, the cell death ratio of progenies derived from podoplanin-positive single cell was significantly lower than that of cells derived from podoplanin-negative cells. Single A431 cells, whose podoplanin expression was suppressed by RNA interference, exhibited increased cell death ratios and decreased frequency of large colony forming. Moreover, the frequency of large colony forming decreased significantly when podoplanin-positive single cells was treated with a ROCK (Rho-associated coiled-coil kinase) inhibitor, whereas no difference was observed in single podoplanin-negative cells. Our current study cleared that high clonal expansion capacity of podoplanin-positive TICs populations was the result of reduced cell death by podoplanin-mediated signaling. Therefore, podoplanin activity may be a therapeutic target in the treatment of squamous cell carcinomas.

Collapse, conquest and Maya survival at Lamanai, Belize

OpenAIRE

Graham, Elizabeth

2000-01-01

The Maya civilization of Central America prompts visions of mysterious stone temples now buried in tropical forest. It is commonly supposed to have collapsed suddenly in the ninth century AD, but some Maya settlements, such as Lamanai, survived into the colonial period. Here a new member of the Institute's academic staff gives a personal account of how working in Belize transformed her understanding of Maya civilization and its aftermath.

Photoreactivation of ultraviolet light-induced damage in cultured fish cells as revealed by increased colony forming ability and decreased content of pyrimidine dimers

International Nuclear Information System (INIS)

Shima, A.; Ikenaga, M.; Egami, N.

1981-01-01

Cultured cells derived from a goldfish were irradiated with 254 nm ultraviolet light. Cell survival and splitting of pyrimidine dimers after photoreactivation treatment with white fluorescent lamps were examined by colony forming ability and by a direct dimer assay, respectively. When UV-irradiated (5 J/m 2 ) cells were illuminated by photoreactivating light, cell survival was enhanced up to a factor of 9(40 min) followed by a decline after prolonged exposures. Exposure of UV-irradiated (15 J/m 2 ) cells to radiation from white fluorescent lamps reduced the amounts of thymine-containing dimers in a photoreactivating fluence dependent manner, up to about 60% reduction at 120 min exposure. Keeping UV-irradiated cells in the dark for up to 120 min did not affect either cell survival or the amount of pyrimidine dimers in DNA, indicating that there were not detectable levels of a dark-repair system in the cells under our conditions. Correlation between photoreactivation of colony forming ability and photoreactivation of the pyrimidine dimers was demonstrated, at least at relatively low fluences of photoreactivating light. (author)

Photoreactivation of ultraviolet light-induced damage in cultured fish cells as revealed by increased colony forming ability and decreased content of pyrimidine dimers

Energy Technology Data Exchange (ETDEWEB)

Shima, A. (Shiga University of Medical Science, Otsu (Japan)); Ikenaga, M. (Osaka Univ. (Japan). Faculty of Medicine); Nikaido, O.; Takebe, H. (Kyoto Univ. (Japan)); Egami, N. (Tokyo Univ. (Japan). Faculty of Science)

1981-03-01

Cultured cells derived from a goldfish were irradiated with 254 nm ultraviolet light. Cell survival and splitting of pyrimidine dimers after photoreactivation treatment with white fluorescent lamps were examined by colony forming ability and by a direct dimer assay, respectively. When UV-irradiated (5 J/m/sup 2/) cells were illuminated by photoreactivating light, cell survival was enhanced up to a factor of 9(40 min) followed by a decline after prolonged exposures. Exposure of UV-irradiated (15 J/m/sup 2/) cells to radiation from white fluorescent lamps reduced the amounts of thymine-containing dimers in a photoreactivating fluence dependent manner, up to about 60% reduction at 120 min exposure. Keeping UV-irradiated cells in the dark for up to 120 min did not affect either cell survival or the amount of pyrimidine dimers in DNA, indicating that there were not detectable levels of a dark-repair system in the cells under our conditions. Correlation between photoreactivation of colony forming ability and photoreactivation of the pyrimidine dimers was demonstrated, at least at relatively low fluences of photoreactivating light.

Cell survival in a simulated Mars environment

Science.gov (United States)

Todd, Paul; Kurk, Michael Andy; Boland, Eugene; Thomas, David

2016-07-01

The most ancient life forms on earth date back comfortably to the time when liquid water was believed to be abundant on Mars. These ancient life forms include cyanobacteria, contemporary autotrophic earth organisms believed to have descended from ancestors present as long as 3.5 billion years ago. Contemporary cyanobacteria have adapted to the earth environment's harshest conditions (long-term drying, high and low temperature), and, being autotrophic, they are among the most likely life forms to withstand space travel and the Mars environment. However, it is unlikely that humans would unwittingly contaminate a planetary spacecraft with these microbes. One the other hand, heterotrophic microbes that co-habit with humans are more likely spacecraft contaminants, as history attests. Indeed, soil samples from the Atacama desert have yielded colony-forming organisms resembling enteric bacteria. There is a need to understand the survivability of cyanobacteria (likely survivors, unlikely contaminants) and heterotrophic eubacteria (unlikely survivors, likely contaminants) under simulated planetary conditions. A 35-day test was performed in a commercial planetary simulation system (Techshot, Inc., Greenville, IN) in which the minimum night-time temperature was -80 C, the maximum daytime temperature was +26 C, the simulated day-night light cycle in earth hours was 12-on and 12-off, and the total pressure of the pure CO _{2} atmosphere was maintained below 11 mbar. Any water present was allowed to equilibrate with the changing temperature and pressure. The gas phase was sampled into a CR1-A low-pressure hygrometer (Buck Technologies, Boulder, CO), and dew/frost point was measured once every hour and recorded on a data logger, along with the varying temperature in the chamber, from which the partial pressure of water was calculated. According to measurements there was no liquid water present throughout the test except during the initial pump-down period when aqueous specimens

An American termite in Paris: temporal colony dynamics.

Science.gov (United States)

Baudouin, Guillaume; Dedeine, Franck; Bech, Nicolas; Bankhead-Dronnet, Stéphanie; Dupont, Simon; Bagnères, Anne-Geneviève

2017-12-01

Termites of the genus Reticulitermes are widespread invaders, particularly in urban habitats. Their cryptic and subterranean lifestyle makes them difficult to detect, and we know little about their colony dynamics over time. In this study we examined the persistence of Reticulitermes flavipes (Kollar) colonies in the city of Paris over a period of 15 years. The aim was (1) to define the boundaries of colonies sampled within the same four areas over two sampling periods, (2) to determine whether the colonies identified during the first sampling period persisted to the second sampling period, and (3) to compare the results obtained when colonies were delineated using a standard population genetic approach versus a Bayesian clustering method that combined both spatial and genetic information. Herein, colony delineations were inferred from genetic differences at nine microsatellite loci and one mitochondrial locus. Four of the 18 identified colonies did not show significant differences in their genotype distributions between the two sampling periods. While allelic richness was low, making it hard to reliably distinguish colony family type, most colonies appeared to retain the same breeding structure over time. These large and expansive colonies showed an important ability to fuse (39% were mixed-family colonies), contained hundreds of reproductives and displayed evidence of isolation-by-distance, suggesting budding dispersal. These traits, which favor colony persistence over time, present a challenge for pest control efforts, which apply treatment locally. The other colonies showed significant differences, but we cannot exclude the possibility that their genotype distributions simply changed over time.

Proton Radiotherapy for Pediatric Ewing's Sarcoma: Initial Clinical Outcomes

Energy Technology Data Exchange (ETDEWEB)

Rombi, Barbara [ATreP (Provincial Agency for Proton Therapy), Trento (Italy); DeLaney, Thomas F.; MacDonald, Shannon M. [Department of Radiation Oncology, Massachusetts General Hospital-Harvard Medical School, Boston, MA (United States); Huang, Mary S.; Ebb, David H. [Department of Pediatric Hematology and Oncology, Massachusetts General Hospital-Harvard Medical School, Boston, MA (United States); Liebsch, Norbert J. [Department of Radiation Oncology, Massachusetts General Hospital-Harvard Medical School, Boston, MA (United States); Raskin, Kevin A. [Department of Orthopaedic Surgery, Massachusetts General Hospital-Harvard Medical School, Boston, MA (United States); Yeap, Beow Y. [Department of Medicine, Massachusetts General Hospital-Harvard Medical School, Boston, MA (United States); Marcus, Karen J. [Division of Radiation Oncology, Children' s Hospital Boston, MA (United States); Tarbell, Nancy J. [Department of Radiation Oncology, Massachusetts General Hospital-Harvard Medical School, Boston, MA (United States); Yock, Torunn I., E-mail: tyock@partners.org [Department of Radiation Oncology, Massachusetts General Hospital-Harvard Medical School, Boston, MA (United States)

2012-03-01

Purpose: Proton radiotherapy (PT) has been prescribed similarly to photon radiotherapy to achieve comparable disease control rates at comparable doses. The chief advantage of protons in this setting is to reduce acute and late toxicities by decreasing the amount of normal tissue irradiated. We report the preliminary clinical outcomes including late effects on our pediatric Ewing's sarcoma patients treated with PT at the Francis H. Burr Proton Therapy Center at Massachusetts General Hospital (Boston, MA). Methods and Materials: This was a retrospective review of the medical records of 30 children with Ewing's sarcoma who were treated with PT between April 2003 and April 2009. Results: A total of 14 male and 16 female patients with tumors in several anatomic sites were treated with PT at a median age of 10 years. The median dose was 54 Gy (relative biological effectiveness) with a median follow-up of 38.4 months. The 3-year actuarial rates of event-free survival, local control, and overall survival were 60%, 86%, and 89%, respectively. PT was acutely well tolerated, with mostly mild-to-moderate skin reactions. At the time of writing, the only serious late effects have been four hematologic malignancies, which are known risks of topoisomerase and anthracyline exposure. Conclusions: Proton radiotherapy was well tolerated, with few adverse events. Longer follow-up is needed to more fully assess tumor control and late effects, but the preliminary results are encouraging.

Post-Colonial Theory and Action Research

Directory of Open Access Journals (Sweden)

Jim Parsons

2011-02-01

Full Text Available This essay explores connections between post-colonial theory and action research. Post-colonial theory is committed to addressing the plague of colonialism. Action research, at its core, promises to problematize uncontested ‘colonial’ hegemonies of any form. Both post-colonial theory and action research engage dialogic, critically reflective and collaborative values to offer a fuller range of human wisdom. The authors contend that post-colonialism theory calls for justice and seeks to speak to social and psychological suffering, exploitation, violence and enslavement done to the powerless victims of colonization around the world by challenging the superiority of dominant perspectives and seeking to re-position and empower the marginalized and subordinated. In similar ways, action research works to eradicate oppression, powerlessness and worthlessness by affirming solidarity with the oppressed, helping humans move from passive to active and by fundamentally reshaping power. Because both post-colonial theory and action research position the insider or oppressed in an ethic of efficacy, it values community, relationships, communication and equality, and is committed to reciprocity, reflexivity and reflection. Thus, both hold the potential to help reconstruct conditions for a more democratic and just society

Post-Colonial Theory and Action Research

Directory of Open Access Journals (Sweden)

Jim B. Parsons

2011-04-01

Full Text Available This essay explores connections between post-colonial theory and action research. Post-colonial theory is committed to addressing the plague of colonialism. Action research, at its core, promises to problematize uncontested ‘colonial’ hegemonies of any form. Both post-colonial theory and action research engage dialogic, critically reflective and collaborative values to offer a fuller range of human wisdom. The authors contend that post-colonialism theory calls for justice and seeks to speak to social and psychological suffering, exploitation, violence and enslavement done to the powerless victims of colonization around the world by challenging the superiority of dominant perspectives and seeking to re-position and empower the marginalized and subordinated. In similar ways, action research works to eradicate oppression, powerlessness and worthlessness by affirming solidarity with the oppressed, helping humans move from passive to active and by fundamentally reshaping power. Because both post-colonial theory and action research position the insider or oppressed in an ethic of efficacy, it values community, relationships, communication and equality, and is committed to reciprocity, reflexivity and reflection. Thus, both hold the potential to help reconstruct conditions for a more democratic and just society.

Colony formation in the cyanobacterium Microcystis.

Science.gov (United States)

Xiao, Man; Li, Ming; Reynolds, Colin S

2018-02-22

Morphological evolution from a unicellular to multicellular state provides greater opportunities for organisms to attain larger and more complex living forms. As the most common freshwater cyanobacterial genus, Microcystis is a unicellular microorganism, with high phenotypic plasticity, which forms colonies and blooms in lakes and reservoirs worldwide. We conducted a systematic review of field studies from the 1990s to 2017 where Microcystis was dominant. Microcystis was detected as the dominant genus in waterbodies from temperate to subtropical and tropical zones. Unicellular Microcystis spp. can be induced to form colonies by adjusting biotic and abiotic factors in laboratory. Colony formation by cell division has been induced by zooplankton filtrate, high Pb 2+ concentration, the presence of another cyanobacterium (Cylindrospermopsis raciborskii), heterotrophic bacteria, and by low temperature and light intensity. Colony formation by cell adhesion can be induced by zooplankton grazing, high Ca 2+ concentration, and microcystins. We hypothesise that single cells of all Microcystis morphospecies initially form colonies with a similar morphology to those found in the early spring. These colonies gradually change their morphology to that of M. ichthyoblabe, M. wesenbergii and M. aeruginosa with changing environmental conditions. Colony formation provides Microcystis with many ecological advantages, including adaption to varying light, sustained growth under poor nutrient supply, protection from chemical stressors and protection from grazing. These benefits represent passive tactics responding to environmental stress. Microcystis colonies form at the cost of decreased specific growth rates compared with a unicellular habit. Large colony size allows Microcystis to attain rapid floating velocities (maximum recorded for a single colony, ∼ 10.08 m h -1 ) that enable them to develop and maintain a large biomass near the surface of eutrophic lakes, where they may shade

Partial Breast Radiation Therapy With Proton Beam: 5-Year Results With Cosmetic Outcomes

Energy Technology Data Exchange (ETDEWEB)

Bush, David A., E-mail: dbush@llu.edu [Department of Radiation Oncology, Loma Linda University Medical Center, Loma Linda, California (United States); Do, Sharon [Department of Radiation Oncology, Loma Linda University Medical Center, Loma Linda, California (United States); Lum, Sharon; Garberoglio, Carlos [Department of Surgical Oncology, Loma Linda University Medical Center, Loma Linda, California (United States); Mirshahidi, Hamid [Department of Medical Oncology, Loma Linda University Medical Center, Loma Linda, California (United States); Patyal, Baldev; Grove, Roger; Slater, Jerry D. [Department of Radiation Oncology, Loma Linda University Medical Center, Loma Linda, California (United States)

2014-11-01

Purpose: We updated our previous report of a phase 2 trial using proton beam radiation therapy to deliver partial breast irradiation (PBI) in patients with early stage breast cancer. Methods and Materials: Eligible subjects had invasive nonlobular carcinoma with a maximal dimension of 3 cm. Patients underwent partial mastectomy with negative margins; axillary lymph nodes were negative on sampling. Subjects received postoperative proton beam radiation therapy to the surgical bed. The dose delivered was 40 Gy in 10 fractions, once daily over 2 weeks. Multiple fields were treated daily, and skin-sparing techniques were used. Following treatment, patients were evaluated with clinical assessments and annual mammograms to monitor toxicity, tumor recurrence, and cosmesis. Results: One hundred subjects were enrolled and treated. All patients completed the assigned treatment and were available for post-treatment analysis. The median follow-up was 60 months. Patients had a mean age of 63 years; 90% had ductal histology; the average tumor size was 1.3 cm. Actuarial data at 5 years included ipsilateral breast tumor recurrence-free survival of 97% (95% confidence interval: 100%-93%); disease-free survival of 94%; and overall survival of 95%. There were no cases of grade 3 or higher acute skin reactions, and late skin reactions included 7 cases of grade 1 telangiectasia. Patient- and physician-reported cosmesis was good to excellent in 90% of responses, was not changed from baseline measurements, and was well maintained throughout the entire 5-year follow-up period. Conclusions: Proton beam radiation therapy for PBI produced excellent ipsilateral breast recurrence-free survival with minimal toxicity. The treatment proved to be adaptable to all breast sizes and lumpectomy cavity configurations. Cosmetic results appear to be excellent and unchanged from baseline out to 5 years following treatment. Cosmetic results may be improved over those reported with photon

CHRISTIANITY AND COLONIALISM IN SOME ENGLISH SHORT STORIES

Directory of Open Access Journals (Sweden)

Tatang Iskarna

2017-04-01

Full Text Available Colonial and postcolonial studies are often linked to the power domination of the West upon the East in the way that the East economically, politically, and socially oppressed. Colonialism is often associated with three elements, the explorers dealing with geographical information, missionaries approaching the local people culturally, and the colonial administrators ruling the colony. Gold, glory, and gospel are the European’s concern. However, in representing the relation between Christianity and colonialism there is critical dialectic amongst historians, anthropologists, Christian missions, or cultural critics. Some propose that Christianity is considered to be the religious arm of colonialism. Others state that Christianity is spread without any secular interest as it is a great commandment of Jesus Christ. A few believe that Christianity give critical resistance against colonialism. The relation between Christianity and colonialism cannot be simplified as being neutral, in complicity, or in opposition. So, it is worth-discussing to understand how European writers construct the relation between Christianity and colonialism in their literary work. How Christianity is constructed and how Christianity is related to colonialism will be discussed in this paper. Using postcolonial paradigm, two English short stories will be analyzed in that way. They are Rudyard Kipling’s “Lispeth” and Doris Lessing’s “No Witchcraft for Sale”.

Collapse, conquest and Maya survival at Lamanai, Belize

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Elizabeth Graham

2000-11-01

Full Text Available The Maya civilization of Central America prompts visions of mysterious stone temples now buried in tropical forest. It is commonly supposed to have collapsed suddenly in the ninth century AD, but some Maya settlements, such as Lamanai, survived into the colonial period. Here a new member of the Institute's academic staff gives a personal account of how working in Belize transformed her understanding of Maya civilization and its aftermath.

A pan-European epidemiological study reveals honey bee colony survival depends on beekeeper education and disease control.

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Antoine Jacques

Full Text Available Reports of honey bee population decline has spurred many national efforts to understand the extent of the problem and to identify causative or associated factors. However, our collective understanding of the factors has been hampered by a lack of joined up trans-national effort. Moreover, the impacts of beekeeper knowledge and beekeeping management practices have often been overlooked, despite honey bees being a managed pollinator. Here, we established a standardised active monitoring network for 5 798 apiaries over two consecutive years to quantify honey bee colony mortality across 17 European countries. Our data demonstrate that overwinter losses ranged between 2% and 32%, and that high summer losses were likely to follow high winter losses. Multivariate Poisson regression models revealed that hobbyist beekeepers with small apiaries and little experience in beekeeping had double the winter mortality rate when compared to professional beekeepers. Furthermore, honey bees kept by professional beekeepers never showed signs of disease, unlike apiaries from hobbyist beekeepers that had symptoms of bacterial infection and heavy Varroa infestation. Our data highlight beekeeper background and apicultural practices as major drivers of honey bee colony losses. The benefits of conducting trans-national monitoring schemes and improving beekeeper training are discussed.

Neonicotinoid pesticides can reduce honeybee colony genetic diversity.

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Nadège Forfert

Full Text Available Neonicotinoid insecticides can cause a variety of adverse sub-lethal effects in bees. In social species such as the honeybee, Apis mellifera, queens are essential for reproduction and colony functioning. Therefore, any negative effect of these agricultural chemicals on the mating success of queens may have serious consequences for the fitness of the entire colony. Queens were exposed to the common neonicotinoid pesticides thiamethoxam and clothianidin during their developmental stage. After mating, their spermathecae were dissected to count the number of stored spermatozoa. Furthermore, their worker offspring were genotyped with DNA microsatellites to determine the number of matings and the genotypic composition of the colony. Colonies providing the male mating partners were also inferred. Both neonicotinoid and control queens mated with drones originating from the same drone source colonies, and stored similar number of spermatozoa. However, queens reared in colonies exposed to both neonicotinoids experienced fewer matings. This resulted in a reduction of the genetic diversity in their colonies (i.e. higher intracolonial relatedness. As decreased genetic diversity among worker bees is known to negatively affect colony vitality, neonicotinoids may have a cryptic effect on colony health by reducing the mating frequency of queens.

Varroa-Virus Interaction in Collapsing Honey Bee Colonies

DEFF Research Database (Denmark)

Francis, Roy Mathew; Nielsen, Steen L.; Kryger, Per

2013-01-01

Varroa mites and viruses are the currently the high-profile suspects in collapsing bee colonies. Therefore, seasonal variation in varroa load and viruses (Acute-Kashmir-Israeli complex (AKI) and Deformed Wing Virus (DWV)) were monitored in a year-long study. We investigated the viral titres...... in honey bees and varroa mites from 23 colonies (15 apiaries) under three treatment conditions: Organic acids (11 colonies), pyrethroid (9 colonies) and untreated (3 colonies). Approximately 200 bees were sampled every month from April 2011 to October 2011, and April 2012. The 200 bees were split to 10...... subsamples of 20 bees and analysed separately, which allows us to determine the prevalence of virus-infected bees. The treatment efficacy was often low for both treatments. In colonies where varroa treatment reduced the mite load, colonies overwintered successfully, allowing the mites and viruses...

First recorded loss of an emperor penguin colony in the recent period of Antarctic regional warming: implications for other colonies.

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Philip N Trathan

Full Text Available In 1948, a small colony of emperor penguins Aptenodytes forsteri was discovered breeding on Emperor Island (67° 51' 52″ S, 68° 42' 20″ W, in the Dion Islands, close to the West Antarctic Peninsula (Stonehouse 1952. When discovered, the colony comprised approximately 150 breeding pairs; these numbers were maintained until 1970, after which time the colony showed a continuous decline. By 1999 there were fewer than 20 pairs, and in 2009 high-resolution aerial photography revealed no remaining trace of the colony. Here we relate the decline and loss of the Emperor Island colony to a well-documented rise in local mean annual air temperature and coincident decline in seasonal sea ice duration. The loss of this colony provides empirical support for recent studies (Barbraud & Weimerskirch 2001; Jenouvrier et al 2005, 2009; Ainley et al 2010; Barber-Meyer et al 2005 that have highlighted the vulnerability of emperor penguins to changes in sea ice duration and distribution. These studies suggest that continued climate change is likely to impact upon future breeding success and colony viability for this species. Furthermore, a recent circumpolar study by Fretwell & Trathan (2009 highlighted those Antarctic coastal regions where colonies appear most vulnerable to such changes. Here we examine which other colonies might be at risk, discussing various ecological factors, some previously unexplored, that may also contribute to future declines. The implications of this are important for future modelling work and for understanding which colonies actually are most vulnerable.

Proton Therapy for Spinal Ependymomas: Planning, Acute Toxicities, and Preliminary Outcomes

Energy Technology Data Exchange (ETDEWEB)

Amsbaugh, Mark J. [Division of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Grosshans, David R., E-mail: dgrossha@mdanderson.org [Division of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States); McAleer, Mary Frances; Zhu, Ron; Wages, Cody; Crawford, Cody N.; Palmer, Matthew; De Gracia, Beth; Woo Shiao; Mahajan, Anita [Division of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States)

2012-08-01

Purpose: To report acute toxicities and preliminary outcomes for pediatric patients with ependymomas of the spine treated with proton beam therapy at the MD Anderson Cancer Center. Methods and Materials: Eight pediatric patients received proton beam irradiation between October 2006 and September 2010 for spinal ependymomas. Toxicity data were collected weekly during radiation therapy and all follow-up visits. Toxicities were graded according to the Common Terminology Criteria for Adverse Events version 3.0. Results: All patients had surgical resection of the tumor before irradiation (7 subtotal resection and 1 gross total resection). Six patients had World Health Organization Grade I ependymomas, and two had World Health Organization Grade II ependymomas. Patients had up to 3 surgical interventions before radiation therapy (range, 1-3; median, 1). Three patients received proton therapy after recurrence and five as part of their primary management. The entire vertebral body was treated in all but 2 patients. The mean radiation dose was 51.1 cobalt gray equivalents (range, 45 to 54 cobalt gray equivalents). With a mean follow-up of 26 months from the radiation therapy start date (range, 7-51 months), local control, event-free survival, and overall survival rates were all 100%. The most common toxicities during treatment were Grade 1 or 2 erythema (75%) and Grade 1 fatigue (38%). No patients had a Grade 3 or higher adverse event. Proton therapy dramatically reduced dose to all normal tissues anterior to the vertebral bodies in comparison to photon therapy. Conclusion: Preliminary outcomes show the expected control rates with favorable acute toxicity profiles. Proton beam therapy offers a powerful treatment option in the pediatric population, where adverse events related to radiation exposure are of concern. Extended follow-up will be required to assess for late recurrences and long-term adverse effects.

Proton radiography to improve proton therapy treatment

NARCIS (Netherlands)

Takatsu, J.; van der Graaf, E. R.; van Goethem, Marc-Jan; van Beuzekom, M.; Klaver, T.; Visser, Jan; Brandenburg, S.; Biegun, A. K.

The quality of cancer treatment with protons critically depends on an accurate prediction of the proton stopping powers for the tissues traversed by the protons. Today, treatment planning in proton radiotherapy is based on stopping power calculations from densities of X-ray Computed Tomography (CT)

Critical evaluation of branch polarity and apical dominance as dictators of colony astogeny in a branching coral.

Directory of Open Access Journals (Sweden)

Lee Shaish

Full Text Available The high morphological resemblance between branching corals and trees, can lead to comparative studies on pattern formation traits, best exemplified in plants and in some cnidarians. Here, 81 branches of similar size of the hermatypic coral Stylophora pistillata were lopped of three different genets, their skeletons marked with alizarin red-S, and divided haphazardly into three morphometric treatment groups: (I upright position; (II horizontal position, intact tip; and (III horizontal position, cut tip. After 1 y of in-situ growth, the 45 surviving ramets were brought to the laboratory, their tissues removed and their architectures analyzed by 22 morphological parameters (MPs. We found that within 1 y, isolated branches developed into small coral colonies by growing new branches from all branch termini, in all directions. No architectural dissimilarity was assigned among the three studied genets of treatment I colonies. However, a major architectural disparity between treatment I colonies and colonies of treatments II and III was documented as the development of mirror structures from both sides of treatments II and III settings as compared to tip-borne architectures in treatment I colonies. We did not observe apical dominance since fragments grew equally from all branch sides without documented dominant polarity along branch axis. In treatment II colonies, no MP for new branches originating either from tips or from branch bases differed significantly. In treatment III colonies, growth from the cut tip areas was significantly lower compared to the base, again, suggesting lack of apical dominance in this species. Changes in branch polarity revealed genet associated plasticity, which in one of the studied genets, led to enhanced growth. Different genets exhibited canalization flexibility of growth patterns towards either lateral growth, or branch axis extension (skeletal weight and not porosity was measured. This study revealed that colony

Proton radioactivity from proton-rich nuclei

International Nuclear Information System (INIS)

Guzman, F.; Goncalves, M.; Tavares, O.A.P.; Duarte, S.B.; Garcia, F.; Rodriguez, O.

1999-03-01

Half-lives for proton emission from proton-rich nuclei have been calculated by using the effective liquid drop model of heavy-particle decay of nuclei. It is shown that this model is able to offer results or spontaneous proton-emission half-life-values in excellent agreement with the existing experimental data. Predictions of half-life-values for other possible proton-emission cases are present for null orbital angular momentum. (author)

Proton Radiography to Improve Proton Radiotherapy : Simulation Study at Different Proton Beam Energies

NARCIS (Netherlands)

Biegun, Aleksandra; Takatsu, Jun; van Goethem, Marc-Jan; van der Graaf, Emiel; van Beuzekom, Martin; Visser, Jan; Brandenburg, Sijtze

To improve the quality of cancer treatment with protons, a translation of X-ray Computed Tomography (CT) images into a map of the proton stopping powers needs to be more accurate. Proton stopping powers determined from CT images have systematic uncertainties in the calculated proton range in a

Longevity of U cells of differentiated yeast colonies grown on respiratory medium depends on active glycolysis.

Science.gov (United States)

Čáp, Michal; Váchová, Libuše; Palková, Zdena

2015-01-01

Colonies of Saccharomyces cerevisiae laboratory strains pass through specific developmental phases when growing on solid respiratory medium. During entry into the so-called alkali phase, in which ammonia signaling is initiated, 2 prominent cell types are formed within the colonies: U cells in upper colony regions, which have a longevity phenotype and activate the expression of a large number of metabolic genes, and L cells in lower regions, which die more quickly and exhibit a starvation phenotype. Here, we performed a detailed analysis of the activities of enzymes of central carbon metabolism in lysates of both cell types and determined several fermentation end products, showing that previously reported expression differences are reflected in the different enzymatic capabilities of each cell type. Hence, U cells, despite being grown on respiratory medium, behave as fermenting cells, whereas L cells rely on respiratory metabolism and possess active gluconeogenesis. Using a spectrum of different inhibitors, we showed that glycolysis is essential for the formation, and particularly, the survival of U cells. We also showed that β-1,3-glucans that are released from the cell walls of L cells are the most likely source of carbohydrates for U cells.

Proton Beam Therapy for Hepatocellular Carcinoma: A Comparison of Three Treatment Protocols

Energy Technology Data Exchange (ETDEWEB)

Mizumoto, Masashi; Okumura, Toshiyuki; Hashimoto, Takayuki [Proton Medical Research Center, University of Tsukuba, Tsukuba, Ibaraki (Japan); Department of Radiation Oncology, University of Tsukuba, Tsukuba, Ibaraki (Japan); Fukuda, Kuniaki [Department of Gastroenterology, University of Tsukuba, Tsukuba, Ibaraki (Japan); Oshiro, Yoshiko; Fukumitsu, Nobuyoshi [Proton Medical Research Center, University of Tsukuba, Tsukuba, Ibaraki (Japan); Department of Radiation Oncology, University of Tsukuba, Tsukuba, Ibaraki (Japan); Abei, Masato [Department of Gastroenterology, University of Tsukuba, Tsukuba, Ibaraki (Japan); Kawaguchi, Atsushi [Biostatistics Center, Kurume University, Fukuoka (Japan); Hayashi, Yasutaka; Ookawa, Ayako; Hashii, Haruko; Kanemoto, Ayae [Department of Radiation Oncology, University of Tsukuba, Tsukuba, Ibaraki (Japan); Moritake, Takashi [Proton Medical Research Center, University of Tsukuba, Tsukuba, Ibaraki (Japan); Department of Radiation Oncology, University of Tsukuba, Tsukuba, Ibaraki (Japan); Tohno, Eriko [Department of Diagnostic Radiology, University of Tsukuba, Tsukuba, Ibaraki (Japan); Tsuboi, Koji [Proton Medical Research Center, University of Tsukuba, Tsukuba, Ibaraki (Japan); Department of Radiation Oncology, University of Tsukuba, Tsukuba, Ibaraki (Japan); Sakae, Takeji [Proton Medical Research Center, University of Tsukuba, Tsukuba, Ibaraki (Japan); Sakurai, Hideyuki, E-mail: hsakurai@pmrc.tsukuba.ac.jp [Proton Medical Research Center, University of Tsukuba, Tsukuba, Ibaraki (Japan); Department of Radiation Oncology, University of Tsukuba, Tsukuba, Ibaraki (Japan)

2011-11-15

Background: Our previous results for treatment of hepatocellular carcinoma (HCC) with proton beam therapy revealed excellent local control with low toxicity. Three protocols were used to avoid late complications such as gastrointestinal ulceration and bile duct stenosis. In this study, we examined the efficacy of these protocols. Methods and Materials: The subjects were 266 patients (273 HCCs) treated by proton beam therapy at University of Tsukuba between January 2001 and December 2007. Three treatment protocols (A, 66 GyE in 10 fractions; B, 72.6 GyE in 22 fractions; and C, 77 GyE in 35 fractions) were used, depending on the tumor location. Results: Of the 266 patients, 104, 95, and 60 patients were treated with protocols A, B, and C, respectively. Seven patients with double lesions underwent two different protocols. The overall survival rates after 1, 3 and 5 years were 87%, 61%, and 48%, respectively (median survival, 4.2 years). Multivariate analysis showed that better liver function, small clinical target volume, and no prior treatment (outside the irradiated field) were associated with good survival. The local control rates after 1, 3, and 5 years were 98%, 87%, and 81%, respectively. Multivariate analysis did not identify any factors associated with good local control. Conclusions: This study showed that proton beam therapy achieved good local control for HCC using each of three treatment protocols. This suggests that selection of treatment schedules based on tumor location may be used to reduce the risk of late toxicity and maintain good treatment efficacy.

Proton solvation and proton transfer in chemical and electrochemical processes

International Nuclear Information System (INIS)

Lengyel, S.; Conway, B.E.

1983-01-01

This chapter examines the proton solvation and characterization of the H 3 O + ion, proton transfer in chemical ionization processes in solution, continuous proton transfer in conductance processes, and proton transfer in electrode processes. Topics considered include the condition of the proton in solution, the molecular structure of the H 3 O + ion, thermodynamics of proton solvation, overall hydration energy of the proton, hydration of H 3 O + , deuteron solvation, partial molal entropy and volume and the entropy of proton hydration, proton solvation in alcoholic solutions, analogies to electrons in semiconductors, continuous proton transfer in conductance, definition and phenomenology of the unusual mobility of the proton in solution, solvent structure changes in relation to anomalous proton mobility, the kinetics of the proton-transfer event, theories of abnormal proton conductance, and the general theory of the contribution of transfer reactions to overall transport processes

Protons and how they are transported by proton pumps

DEFF Research Database (Denmark)

Buch-Pedersen, Morten Jeppe; Pedersen, Bjørn Panyella; Nissen, Poul

2008-01-01

molecular components that allow the plasma membrane proton H(+)-ATPase to carry out proton transport against large membrane potentials. When divergent proton pumps such as the plasma membrane H(+)-ATPase, bacteriorhodopsin, and F(O)F(1) ATP synthase are compared, unifying mechanistic premises for biological...... proton pumps emerge. Most notably, the minimal pumping apparatus of all pumps consists of a central proton acceptor/donor, a positively charged residue to control pK (a) changes of the proton acceptor/donor, and bound water molecules to facilitate rapid proton transport along proton wires....

JAX Colony Management System (JCMS): an extensible colony and phenotype data management system

OpenAIRE

Donnelly, Chuck J.; McFarland, Mike; Ames, Abigail; Sundberg, Beth; Springer, Dave; Blauth, Peter; Bult, Carol J.

2010-01-01

The Jackson Laboratory Colony Management System (JCMS) is a software application for managing data and information related to research mouse colonies, associated biospecimens, and experimental protocols. JCMS runs directly on computers that run one of the PC Windows® operating systems, but can be accessed via web browser interfaces from any computer running a Windows, Macintosh®, or Linux® operating system. JCMS can be configured for a single user or multiple users in small- to medium-size wo...

Recovery of endo-CFU-S in radio-adaptive survival response in mice

International Nuclear Information System (INIS)

Yonezawa, Morio; Horie, Kiyohito; Kubo, Kihei

2003-01-01

A priming irradiation with 0.45 Gy of X-rays, given 2 weeks prior to the challenging exposures, induces radio-resistance (decrease in bone marrow death rate after mid-lethal irradiations) in mice of C57BL/6 mice. This acquired radio-resistance appeared on day 9 and continued till day 17 after the priming irradiation, with a maximal on days 12-14 and diminished on day 21. The priming irradiation, given 14 days prior to the challenging exposure, increased endogenous spleen colonies on days 12-13 after exposure to 5.0 Gy. Effect of interval time between the priming and the challenging irradiations on the increase in endogenous spleen colonies was also examined. Significant increase of the colonies by the priming irradiation was observed when the interval time was 12-17 and 21 days. The results correspond to the increase of the survival rates on days 12-17 after the challenging irradiations. (author)

Improved Ant Colony Clustering Algorithm and Its Performance Study

Science.gov (United States)

Gao, Wei

2016-01-01

Clustering analysis is used in many disciplines and applications; it is an important tool that descriptively identifies homogeneous groups of objects based on attribute values. The ant colony clustering algorithm is a swarm-intelligent method used for clustering problems that is inspired by the behavior of ant colonies that cluster their corpses and sort their larvae. A new abstraction ant colony clustering algorithm using a data combination mechanism is proposed to improve the computational efficiency and accuracy of the ant colony clustering algorithm. The abstraction ant colony clustering algorithm is used to cluster benchmark problems, and its performance is compared with the ant colony clustering algorithm and other methods used in existing literature. Based on similar computational difficulties and complexities, the results show that the abstraction ant colony clustering algorithm produces results that are not only more accurate but also more efficiently determined than the ant colony clustering algorithm and the other methods. Thus, the abstraction ant colony clustering algorithm can be used for efficient multivariate data clustering. PMID:26839533

Is colonialism history? The declining impact of colonial legacies on African institutional and economic development : The declining impact of colonial legacies on African institutional and economic development

NARCIS (Netherlands)

Maseland, Robbert

2018-01-01

This paper investigates the claim that colonial history has left an enduring imprint on Africa's institutional and economic development. The literature following Acemoglu, Johnson and Robinson (2001) and Sokoloff and Engerman (2000) maintains that different types of colonialism affected the

Local Recurrence After Uveal Melanoma Proton Beam Therapy: Recurrence Types and Prognostic Consequences

International Nuclear Information System (INIS)

Caujolle, Jean-Pierre; Paoli, Vincent; Chamorey, Emmanuel; Maschi, Celia; Baillif, Stéphanie; Herault, Joël; Gastaud, Pierre; Hannoun-Levi, Jean Michel

2013-01-01

Purpose: To study the prognosis of the different types of uveal melanoma recurrences treated by proton beam therapy (PBT). Methods and Materials: This retrospective study analyzed 61 cases of uveal melanoma local recurrences on a total of 1102 patients treated by PBT between June 1991 and December 2010. Survival rates have been determined by using Kaplan-Meier curves. Prognostic factors have been evaluated by using log-rank test or Cox model. Results: Our local recurrence rate was 6.1% at 5 years. These recurrences were divided into 25 patients with marginal recurrences, 18 global recurrences, 12 distant recurrences, and 6 extrascleral extensions. Five factors have been identified as statistically significant risk factors of local recurrence in the univariate analysis: large tumoral diameter, small tumoral volume, low ratio of tumoral volume over eyeball volume, iris root involvement, and safety margin inferior to 1 mm. In the local recurrence-free population, the overall survival rate was 68.7% at 10 years and the specific survival rate was 83.6% at 10 years. In the local recurrence population, the overall survival rate was 43.1% at 10 years and the specific survival rate was 55% at 10 years. The multivariate analysis of death risk factors has shown a better prognosis for marginal recurrences. Conclusion: Survival rate of marginal recurrences is superior to that of the other recurrences. The type of recurrence is a clinical prognostic value to take into account. The influence of local recurrence retreatment by proton beam therapy should be evaluated by novel studies

Local Recurrence After Uveal Melanoma Proton Beam Therapy: Recurrence Types and Prognostic Consequences

Energy Technology Data Exchange (ETDEWEB)

Caujolle, Jean-Pierre, E-mail: ncaujolle@aol.com [Department of Ophthalmology, Saint Roch Hospital, Nice Teaching Hospital, Nice (France); Paoli, Vincent [Department of Ophthalmology, Saint Roch Hospital, Nice Teaching Hospital, Nice (France); Chamorey, Emmanuel [Department of Radiation Oncology, Protontherapy Center, Centre Antoine Lacassagne, Nice (France); Department of Biostatistics and Epidemiology, Centre Antoine Lacassagne, Nice (France); Maschi, Celia; Baillif, Stéphanie [Department of Ophthalmology, Saint Roch Hospital, Nice Teaching Hospital, Nice (France); Herault, Joël [Department of Radiation Oncology, Protontherapy Center, Centre Antoine Lacassagne, Nice (France); Gastaud, Pierre [Department of Ophthalmology, Saint Roch Hospital, Nice Teaching Hospital, Nice (France); Hannoun-Levi, Jean Michel [Department of Radiation Oncology, Protontherapy Center, Centre Antoine Lacassagne, Nice (France)

2013-04-01

Purpose: To study the prognosis of the different types of uveal melanoma recurrences treated by proton beam therapy (PBT). Methods and Materials: This retrospective study analyzed 61 cases of uveal melanoma local recurrences on a total of 1102 patients treated by PBT between June 1991 and December 2010. Survival rates have been determined by using Kaplan-Meier curves. Prognostic factors have been evaluated by using log-rank test or Cox model. Results: Our local recurrence rate was 6.1% at 5 years. These recurrences were divided into 25 patients with marginal recurrences, 18 global recurrences, 12 distant recurrences, and 6 extrascleral extensions. Five factors have been identified as statistically significant risk factors of local recurrence in the univariate analysis: large tumoral diameter, small tumoral volume, low ratio of tumoral volume over eyeball volume, iris root involvement, and safety margin inferior to 1 mm. In the local recurrence-free population, the overall survival rate was 68.7% at 10 years and the specific survival rate was 83.6% at 10 years. In the local recurrence population, the overall survival rate was 43.1% at 10 years and the specific survival rate was 55% at 10 years. The multivariate analysis of death risk factors has shown a better prognosis for marginal recurrences. Conclusion: Survival rate of marginal recurrences is superior to that of the other recurrences. The type of recurrence is a clinical prognostic value to take into account. The influence of local recurrence retreatment by proton beam therapy should be evaluated by novel studies.

Engaging With Colonial Archives: Reflections Of An End-User

Directory of Open Access Journals (Sweden)

Ayodeji Olukoju

2016-06-01

Full Text Available Official and/or public archives were a byproduct of colonial rule in Africa. (Archives are a byproduct of administrative governance everywhere. Given the density and diversity of colonial archival records, historians have tended to rely on them for the study of the colonial period. Publications on the use of archives have not captured the perspective of end-users, who often face peculiar challenges in the use of colonial and metropolitan archives. This paper provides an end-user perspective on colonial archives in Nigeria and the United Kingdom. It highlights the challenges of data collection and prospects of optimal use of archival source material. The discussion is of general application to users of colonial archives especially in the former British colonies in Africa.

Long-term outcomes after proton therapy, with concurrent chemotherapy, for stage II–III inoperable non-small cell lung cancer

International Nuclear Information System (INIS)

Nguyen, Quynh-Nhu; Ly, Ngoc Bui; Komaki, Ritsuko; Levy, Lawrence B.; Gomez, Daniel R.; Chang, Joe Y.; Allen, Pamela K.; Mehran, Reza J.; Lu, Charles; Gillin, Michael; Liao, Zhongxing; Cox, James D.

2015-01-01

Purpose: We report long-term disease control, survival, and toxicity for patients with locally advanced non-small cell lung cancer prospectively treated with concurrent proton therapy and chemotherapy on a nonrandomized case-only observational study. Methods: All patients received passive-scatter proton therapy, planned with 4D-CT–based simulation; all received proton therapy concurrent with weekly chemotherapy. Endpoints were local and distant control, disease-free survival (DFS), and overall survival (OS). Results: The 134 patients (21 stage II, 113 stage III; median age 69 years) had a median gross tumor volume (GTV) of 70 cm 3 (range, 5–753 cm 3 ); 77 patients (57%) received 74 Gy(RBE), and 57 (42%) received 60–72 Gy(RBE) (range, 60–74.1 Gy(RBE)). At a median follow-up time of 4.7 years, median OS times were 40.4 months (stage II) and 30.4 months (stage III). Five-year DFS rates were 17.3% (stage II) and 18.0% (stage III). OS, DFS, and local and distant control rates at 5 years did not differ by disease stage. Age and GTV were related to OS and DFS. Toxicity was tolerable, with 1 grade 4 esophagitis and 16 grade 3 events (2 pneumonitis, 6 esophagitis, 8 dermatitis). Conclusion: This report of outcomes after proton therapy for 134 patients indicated that this regimen produced excellent OS with tolerable toxicity

A Prospective Outcomes Study of Proton Therapy for Chordomas and Chondrosarcomas of the Spine

Energy Technology Data Exchange (ETDEWEB)

Indelicato, Daniel J., E-mail: dindelicato@floridaproton.org [Department of Radiation Oncology, University of Florida College of Medicine, Jacksonville, Florida (United States); Rotondo, Ronny L.; Begosh-Mayne, Dustin [Department of Radiation Oncology, University of Florida College of Medicine, Jacksonville, Florida (United States); Scarborough, Mark T.; Gibbs, C. Parker [Department of Orthopedics and Rehabilitation, University of Florida College of Medicine, Gainesville, Florida (United States); Morris, Christopher G.; Mendenhall, William M. [Department of Radiation Oncology, University of Florida College of Medicine, Jacksonville, Florida (United States)

2016-05-01

Purpose: To evaluate the effectiveness of definitive or adjuvant external beam proton therapy on survival in patients with chordomas and chondrosarcomas of the spine. Methods and Materials: Between March 2007 and May 2013, 51 patients with a median age of 58 years (range, 22-83 years) with chordoma (n=34) or chondrosarcomas (n=17) of the sacrum (n=21), the cervical spine (n=20), and the thoracolumbar spine (n=10) were treated with external beam proton therapy to a median dose of 70.2 Gy(RBE) [range, 64.2-75.6 Gy(RBE)] at our institution. Distant metastases, overall survival, cause-specific survival, local control, and disease-free survival were calculated. Results: The mean follow-up time was 3.7 years (range, 0.3-7.7 years). Across all time points, 25 patients experienced disease recurrence: 18 local recurrences, 6 local and distant recurrences, and 1 distant metastasis. The 4-year rates of overall survival and cause-specific survival were 72%; disease-free survival was 57%, local control was 58%, and freedom from distant metastases was 86%. The median time to local progression was 1.7 years (range, 0.2-6.0 years), and the median time to distant progression was 1.6 years (range, 0.2-6.0 years). The risk factors for local recurrence were age ≤58 years (62% vs 26%; P=.04) and recurrence after prior surgery (29% vs 81%; P=.01). Secondary cancers developed in 2 patients: B-cell lymphoma 5.5 years after treatment and bladder cancer 2 years after treatment. We observed the following toxicities: sacral soft tissue necrosis requiring surgery (n=2), T1 vertebral fracture requiring fusion surgery (n=1), chronic urinary tract infections (n=1), surgery for necrotic bone cyst (n=1), and grade 2 bilateral radiation nephritis (n=1). Conclusion: High-dose proton therapy controls more than half of spinal chordomas and chondrosarcomas and compares favorably with historic photon data. Local progression is the dominant mode of treatment failure and may be reduced by

Laser-induced speckle scatter patterns in Bacillus colonies

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Huisung eKim

2014-10-01

Full Text Available Label-free bacterial colony phenotyping technology called BARDOT (BActerial Rapid Detection using Optical scattering Technology provided successful classification of several different bacteria at the genus, species, and serovar level. Recent experiments with colonies of Bacillus species provided strikingly different characteristics of elastic light scatter (ELS patterns, which were comprised of random speckles compared to other bacteria, which are dominated by concentric rings and spokes. Since this laser-based optical sensor interrogates the whole volume of the colony, 3-D information of micro- and macro-structures are all encoded in the far-field scatter patterns. Here, we present a theoretical model explaining the underlying mechanism of the speckle formation by the colonies from Bacillus species. Except for Bacillus polymyxa, all Bacillus spp. produced random bright spots on the imaging plane, which presumably dependent on the cellular and molecular organization and content within the colony. Our scatter model-based analysis revealed that colony spread resulting in variable surface roughness can modify the wavefront of the scatter field. As the center diameter of the Bacillus spp. colony grew from 500 μm to 900 μm, average speckles area decreased 2-fold and the number of small speckles increased 7-fold. In conclusion, as Bacillus colony grows, the average speckle size in the scatter pattern decreases and the number of smaller speckle increases due to the swarming growth characteristics of bacteria within the colony.

Conservation implications of ameliorating survival of little brown bats with white-nose syndrome.

Science.gov (United States)

Maslo, Brooke; Valent, Mick; Gumbs, John F; Frick, Winifred F

2015-10-01

Management of wildlife populations impacted by novel threats is often challenged by a lack of data on temporal changes in demographic response. Populations may suffer rapid declines from the introduction of new stressors, but how demography changes over time is critical to determining long-term outcomes for populations. White-nose syndrome (WNS), an infectious disease of hibernating bats, has caused massive and rapid population declines in several hibernating species of bats in North America since the disease was first observed on the continent in 2006. Estimating annual survival rates and demographic trends among remnant colonies of hibernating bats that experienced mass mortality from WNS is needed to determine long-term population viability of species impacted by this disease. Using mark-recapture data on infected little brown bats (Myotis lucifugus), we estimated the first apparent annual survival rates for four years following WNS detection at a site. We found strong support for an increasing trend in annual survival, which improved from 0.68 (95% CI = 0.44-0.85) to 0.75 (95% CI = 0.51-0.89) for males and 0.65 (95% CI = 0.44-0.81) to 0.70 (95% CI = 0.50-0.84) for females. These results suggest that stabilization at remnant colonies after mass mortality from WNS may be due to improved survival and not from immigration from other areas. Despite ameliorating survival, our stochastic matrix projection model predicts continued declines for little brown bat populations (λ = 0.95), raising concern for the regional persistence of this species. We conducted a vital rate sensitivity analysis and determined that adult and juvenile survival, as opposed to fecundity, are the demographic parameters most important to target to maximize recovery potential of little brown bat populations in areas impacted by WNS.

Determination of glucose deficiency-induced cell death by mitochondrial ATP generation-driven proton homeostasis

Institute of Scientific and Technical Information of China (English)

Yanfen Cui; Yuanyuan Wang; Miao Liu; Li Qiu; Pan Xing; Xin Wang; Guoguang Ying; Binghui Li

2017-01-01

Glucose is one of major nutrients and its catabolism provides energy and/or building bricks for cell proliferation.Glucose deficiency results in cell death.However,the underlying mechanism still remains elusive.By using our recently developed method to monitor real-time cellular apoptosis and necrosis,we show that glucose deprivation can directly elicit necrosis,which is promoted by mitochondrial impairment,depending on mitochondrial adenosine triphosphate (ATP) generation instead of ATP depletion.We demonstrate that glucose metabolism is the major source to produce protons.Glucose deficiency leads to lack of proton provision while mitochondrial electron transfer chain continues consuming protons to generate energy,which provokes a compensatory iysosomal proton effiux and resultant increased lysosomal pH.This lysosomal alkalinization can trigger apoptosis or necrosis depending on the extent of alkalinization.Taken together,our results build up a metabolic connection between glycolysis,mitochondrion,and lysosome,and reveal an essential role of glucose metabolism in maintaining proton homeostasis to support cell survival.

Coalescing colony model: Mean-field, scaling, and geometry

Science.gov (United States)

Carra, Giulia; Mallick, Kirone; Barthelemy, Marc

2017-12-01

We analyze the coalescing model where a `primary' colony grows and randomly emits secondary colonies that spread and eventually coalesce with it. This model describes population proliferation in theoretical ecology, tumor growth, and is also of great interest for modeling urban sprawl. Assuming the primary colony to be always circular of radius r (t ) and the emission rate proportional to r (t) θ , where θ >0 , we derive the mean-field equations governing the dynamics of the primary colony, calculate the scaling exponents versus θ , and compare our results with numerical simulations. We then critically test the validity of the circular approximation for the colony shape and show that it is sound for a constant emission rate (θ =0 ). However, when the emission rate is proportional to the perimeter, the circular approximation breaks down and the roughness of the primary colony cannot be discarded, thus modifying the scaling exponents.

Reduction in predator defense in the presence of neighbors in a colonial fish.

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Franziska C Schädelin

Full Text Available Predation pressure has long been considered a leading explanation of colonies, where close neighbors may reduce predation via dilution, alarming or group predator attacks. Attacking predators may be costly in terms of energy and survival, leading to the question of how neighbors contribute to predator deterrence in relationship to each other. Two hypotheses explaining the relative efforts made by neighbors are byproduct-mutualism, which occurs when breeders inadvertently attack predators by defending their nests, and reciprocity, which occurs when breeders deliberately exchange predator defense efforts with neighbors. Most studies investigating group nest defense have been performed with birds. However, colonial fish may constitute a more practical model system for an experimental approach because of the greater ability of researchers to manipulate their environment. We investigated in the colonial fish, Neolamprologus caudopunctatus, whether prospecting pairs preferred to breed near conspecifics or solitarily, and how breeders invested in anti-predator defense in relation to neighbors. In a simple choice test, prospecting pairs selected breeding sites close to neighbors versus a solitary site. Predators were then sequentially presented to the newly established test pairs, the previously established stimulus pairs or in between the two pairs. Test pairs attacked the predator eight times more frequently when they were presented on their non-neighbor side compared to between the two breeding sites, where stimulus pairs maintained high attack rates. Thus, by joining an established pair, test pairs were able to reduce their anti-predator efforts near neighbors, at no apparent cost to the stimulus pairs. These findings are unlikely to be explained by reciprocity or byproduct-mutualism. Our results instead suggest a commensal relationship in which new pairs exploit the high anti-predator efforts of established pairs, which invest similarly with or

Hegemony and Accommodation in the History Curriculum in Colonial Botswana

Science.gov (United States)

Mafela, Lily

2014-01-01

A reanalysis of colonial education is necessary in order to highlight its multifaceted and hybrid nature in specific colonial contexts. Although in general, colonial education served the socio-political needs of the colonial machinery, the colonial government's hegemonic authority over the school curriculum did not operate as a totalising project.…

Colonial Institutions

DEFF Research Database (Denmark)

McAtackney, Laura; Palmer, Russell

2016-01-01

and the USA which reveal that the study of colonial institutions should not be limited to the functional life of these institutions—or solely those that take the form of monumental architecture—but should include the long shadow of “imperial debris” (Stoler 2008) and immaterial institutions....

Proton Therapy for Reirradiation of Progressive or Recurrent Chordoma

Energy Technology Data Exchange (ETDEWEB)

McDonald, Mark W., E-mail: mmcdona2@iuhealth.org [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana (United States); Indiana University Health Proton Therapy Center, Bloomington, Indiana (United States); Linton, Okechuckwu R. [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana (United States); Shah, Mitesh V. [Department of Neurosurgery, Indiana University School of Medicine, Indianapolis, Indiana (United States)

2013-12-01

Purpose: To report the results in patients reirradiated with proton therapy for recurrent or progressive chordoma, with or without salvage surgery. Methods and Materials: A retrospective review of 16 consecutive patients treated from 2005 to 2012 was performed. All patients had received at least 1 prior course of radiation therapy to the same area, and all but 1 patient had at least 1 surgical resection for disease before receiving reirradiation. At the time of recurrence or progression, half of the patients underwent additional salvage surgery before receiving reirradiation. The median prior dose of radiation was 75.2 Gy (range, 40-79.2 Gy). Six patients had received prior proton therapy, and the remainder had received photon radiation. The median gross tumor volume at the time of reirradiation was 71 cm{sup 3} (range, 0-701 cm{sup 3}). Reirradiation occurred at a median interval of 37 months after prior radiation (range, 12-129 months), and the median dose of reirradiation was 75.6 Gy (relative biological effectiveness [RBE]) (range. 71.2-79.2 Gy [RBE]), given in standard daily fractionation (n=14) or hyperfractionation (n=2). Results: The median follow-up time was 23 months (range, 6-63 months); it was 26 months in patients alive at the last follow-up visit (range, 12-63 months). The 2-year estimate for local control was 85%, overall survival 80%, chordoma-specific survival 88%, and development of distant metastases 20%. Four patients have had local progression: 3 in-field and 1 marginal. Late toxicity included grade 3 bitemporal lobe radionecrosis in 1 patient that improved with hyperbaric oxygen, a grade 4 cerebrospinal fluid leak with meningitis in 1 patient, and a grade 4 ischemic brainstem stroke (out of radiation field) in 1 patient, with subsequent neurologic recovery. Conclusions: Full-dose proton reirradiation provided encouraging initial disease control and overall survival for patients with recurrent or progressive chordoma, although additional

Proton Therapy for Reirradiation of Progressive or Recurrent Chordoma

International Nuclear Information System (INIS)

McDonald, Mark W.; Linton, Okechuckwu R.; Shah, Mitesh V.

2013-01-01

Purpose: To report the results in patients reirradiated with proton therapy for recurrent or progressive chordoma, with or without salvage surgery. Methods and Materials: A retrospective review of 16 consecutive patients treated from 2005 to 2012 was performed. All patients had received at least 1 prior course of radiation therapy to the same area, and all but 1 patient had at least 1 surgical resection for disease before receiving reirradiation. At the time of recurrence or progression, half of the patients underwent additional salvage surgery before receiving reirradiation. The median prior dose of radiation was 75.2 Gy (range, 40-79.2 Gy). Six patients had received prior proton therapy, and the remainder had received photon radiation. The median gross tumor volume at the time of reirradiation was 71 cm 3 (range, 0-701 cm 3 ). Reirradiation occurred at a median interval of 37 months after prior radiation (range, 12-129 months), and the median dose of reirradiation was 75.6 Gy (relative biological effectiveness [RBE]) (range. 71.2-79.2 Gy [RBE]), given in standard daily fractionation (n=14) or hyperfractionation (n=2). Results: The median follow-up time was 23 months (range, 6-63 months); it was 26 months in patients alive at the last follow-up visit (range, 12-63 months). The 2-year estimate for local control was 85%, overall survival 80%, chordoma-specific survival 88%, and development of distant metastases 20%. Four patients have had local progression: 3 in-field and 1 marginal. Late toxicity included grade 3 bitemporal lobe radionecrosis in 1 patient that improved with hyperbaric oxygen, a grade 4 cerebrospinal fluid leak with meningitis in 1 patient, and a grade 4 ischemic brainstem stroke (out of radiation field) in 1 patient, with subsequent neurologic recovery. Conclusions: Full-dose proton reirradiation provided encouraging initial disease control and overall survival for patients with recurrent or progressive chordoma, although additional toxicities may

Scott Richard Lyons, X-marks: Native Signatures of Assent. , Steve Russell, Sequoyah Rising: Problems in Post-Colonial Tribal Governance. , Sean Kicummah Teuton, Red Land, Red Power: Grounding Knowledge in the American Indian Novel. , Gerald Vizenor, Native Liberty: Natural Reason and Cultural Survivance.

Directory of Open Access Journals (Sweden)

James Mackay

2011-09-01

Full Text Available That American Indian nations have survived into the 21st century should be an occasion for celebration, given how truly close Native America came to a total obliteration. A combination of disease, vicious colonial warfare and the use of education as a weapon to “kill the Indian, save the man” had by the beginning of the 19th century reduced the number of people in the United States willing to claim Native ancestry in the census to just 250,000. (There were, of course, many more, but Indian bl...

Honey bee (Apis mellifera) drones survive oxidative stress due to increased tolerance instead of avoidance or repair of oxidative damage.

Science.gov (United States)

Li-Byarlay, Hongmei; Huang, Ming Hua; Simone-Finstrom, Michael; Strand, Micheline K; Tarpy, David R; Rueppell, Olav

2016-10-01

Oxidative stress can lead to premature aging symptoms and cause acute mortality at higher doses in a range of organisms. Oxidative stress resistance and longevity are mechanistically and phenotypically linked; considerable variation in oxidative stress resistance exists among and within species and typically covaries with life expectancy. However, it is unclear whether stress-resistant, long-lived individuals avoid, repair, or tolerate molecular damage to survive longer than others. The honey bee (Apis mellifera L.) is an emerging model system that is well-suited to address this question. Furthermore, this species is the most economically important pollinator, whose health may be compromised by pesticide exposure, including oxidative stressors. Here, we develop a protocol for inducing oxidative stress in honey bee males (drones) via Paraquat injection. After injection, individuals from different colony sources were kept in common social conditions to monitor their survival compared to saline-injected controls. Oxidative stress was measured in susceptible and resistant individuals. Paraquat drastically reduced survival but individuals varied in their resistance to treatment within and among colony sources. Longer-lived individuals exhibited higher levels of lipid peroxidation than individuals dying early. In contrast, the level of protein carbonylation was not significantly different between the two groups. This first study of oxidative stress in male honey bees suggests that survival of an acute oxidative stressor is due to tolerance, not prevention or repair, of oxidative damage to lipids. It also demonstrates colony differences in oxidative stress resistance that might be useful for breeding stress-resistant honey bees. Copyright © 2016 Elsevier Inc. All rights reserved.

Dealing with water deficit in Atta ant colonies: large ants scout for water while small ants transport it

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Antonio Carlos Da-Silva

2012-07-01

Leafcutter ants (Atta sexdens rubropilosa (Forel 1908 have an elaborate social organization, complete with caste divisions. Activities carried out by specialist groups contribute to the overall success and survival of the colony when it is confronted with environmental challenges such as dehydration. Ants detect variations in humidity inside the nest and react by activating several types of behavior that enhance water uptake and decrease water loss, but it is not clear whether or not a single caste collects water regardless of the cost of bringing this resource back to the colony. Accordingly, we investigated water collection activities in three colonies of Atta sexdens rubropilosa experimentally exposed to water stress. Specifically, we analyzed whether or not the same ant caste foraged for water, regardless of the absolute energetic cost (distance of transporting this resource back to the colony. Our experimental design offered water sources at 0 m, 1 m and 10 m from the nest. We studied the body size of ants near the water sources from the initial offer of water (time  =  0 to 120 min, and tested for specialization. We observed a reduction in the average size and variance of ants that corroborated the specialization hypothesis. Although the temporal course of specialization changed with distance, the final outcome was similar among distances. Thus, we conclude that, for this species, a specialist (our use of the word “specialist” does not mean exclusive task force is responsible for collecting water, regardless of the cost of transporting water back to the colony.

Possible natural hybridization of two morphologically distinct species of Acropora (Cnidaria, Scleractinia in the Pacific: fertilization and larval survival rates.

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Naoko Isomura

Full Text Available Natural hybridization of corals in the Indo-Pacific has been considered rather rare. However, field studies have observed many corals with intermediate interspecific or unusual morphologies. Given that the existence of F1 hybrids with intermediate interspecific morphologies has been proven in the Caribbean, hybrids may also inhabit the Indo-Pacific and occur more frequently than expected. In this study, we focused on two morphologically different species, Acropora florida and A. intermedia, and performed crossing experiments at Akajima Island, Japan. Results showed that these species could hybridize in both directions via eggs and sperm, but that fertilization rates significantly differed according to which species provided eggs. These results are similar to those reported from the Caribbean. Although all embryos developed normally to the planular larval stage, the developmental processes of some hybrid embryos were delayed by approximately 1 h compared with conspecific embryos, suggesting that fertilization occurred 1 h later in interspecific crosses than in intraspecific crosses. More successful hybridization could occur under conditions with low numbers of conspecific colonies. Additionally, a comparison of survival rates between hybrid and intraspecific larvae revealed that intra- and interspecific larvae produced from eggs of A. florida survived for significantly longer than those produced from eggs of A. intermedia. Considering these data, under specific conditions, hybrids can be expected to be produced and survive in nature in the Pacific. Furthermore, we identified one colony with intermediate morphology between A. florida and A. intermedia in the field. This colony was fertilized only by eggs of A. florida, with high fertilization rates, suggesting that this colony would be a hybrid of these two species and might be backcrossed.

Impact of resonance decays on critical point signals in net-proton fluctuations

Energy Technology Data Exchange (ETDEWEB)

Bluhm, Marcus; Schaefer, Thomas [North Carolina State University, Department of Physics, Raleigh, NC (United States); Nahrgang, Marlene [SUBATECH, UMR 6457, Universite de Nantes, Ecole des Mines de Nantes, IN2P3/CNRS, Nantes (France); Duke University, Department of Physics, Durham, NC (United States); Bass, Steffen A. [Duke University, Department of Physics, Durham, NC (United States)

2017-04-15

The non-monotonic beam energy dependence of the higher cumulants of net-proton fluctuations is a widely studied signature of the conjectured presence of a critical point in the QCD phase diagram. In this work we study the effect of resonance decays on critical fluctuations. We show that resonance effects reduce the signatures of critical fluctuations, but that for reasonable parameter choices critical effects in the net-proton cumulants survive. The relative role of resonance decays has a weak dependence on the order of the cumulants studied with a slightly stronger suppression of critical effects for higher-order cumulants. (orig.)

21 CFR 866.2170 - Automated colony counter.

Science.gov (United States)

2010-04-01

...) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2170 Automated colony counter. (a) Identification. An automated colony counter is a mechanical device intended for medical...

Proton decay: spectroscopic probe beyond the proton drip line

International Nuclear Information System (INIS)

Seweryniak, D; Davids, C N; Robinson, A; Woods, P J; Blank, B; Carpenter, M P; Davinson, T; Freeman, S J; Hammond, N; Hoteling, N; Janssens, R V F; Khoo, T L; Liu, Z; Mukherjee, G; Shergur, J; Sinha, S; Sonzogni, A A; Walters, W B; Woehr, A

2005-01-01

Proton decay has been transformed in recent years from an exotic phenomenon into a powerful spectroscopic tool. The frontiers of experimental and theoretical proton-decay studies will be reviewed. Different aspects of proton decay will be illustrated with recent results on the deformed proton emitter 135 Tb, the odd-odd deformed proton emitter 130 Eu, the complex fine structure in the odd-odd 146 Tm nucleus and on excited states in the transitional proton emitter 145 Tm

Relative biological effectiveness in canine osteosarcoma cells irradiated with accelerated charged particles

Science.gov (United States)

Maeda, Junko; Cartwright, Ian M.; Haskins, Jeremy S.; Fujii, Yoshihiro; Fujisawa, Hiroshi; Hirakawa, Hirokazu; Uesaka, Mitsuru; Kitamura, Hisashi; Fujimori, Akira; Thamm, Douglas H.; Kato, Takamitsu A.

2016-01-01

Heavy ions, characterized by high linear energy transfer (LET) radiation, have advantages compared with low LET protons and photons in their biological effects. The application of heavy ions within veterinary clinics requires additional background information to determine heavy ion efficacy. In the present study, comparison of the cell-killing effects of photons, protons and heavy ions was investigated in canine osteosarcoma (OSA) cells in vitro. A total of four canine OSA cell lines with various radiosensitivities were irradiated with 137Cs gamma-rays, monoenergetic proton beams, 50 keV/µm carbon ion spread out Bragg peak beams and 200 keV/µm iron ion monoenergetic beams. Clonogenic survival was examined using colony-forming as says, and relative biological effectiveness (RBE) values were calculated relative to gamma-rays using the D10 value, which is determined as the dose (Gy) resulting in 10% survival. For proton irradiation, the RBE values for all four cell lines were 1.0–1.1. For all four cell lines, exposure to carbon ions yielded a decreased cell survival compared with gamma-rays, with the RBE values ranging from 1.56–2.10. Iron ions yielded the lowest cell survival among tested radiation types, with RBE values ranging from 3.51–3.69 observed in the three radioresistant cell lines. The radiosensitive cell line investigated demonstrated similar cell survival for carbon and iron ion irradiation. The results of the present study suggest that heavy ions are more effective for killing radioresistant canine OSA cells when compared with gamma-rays and protons. This markedly increased efficiency of cell killing is an attractive reason for utilizing heavy ions for radioresistant canine OSA. PMID:27446477

Inbred or Outbred? Genetic Diversity in Laboratory Rodent Colonies

Science.gov (United States)

Brekke, Thomas D.; Steele, Katherine A.; Mulley, John F.

2017-01-01

Nonmodel rodents are widely used as subjects for both basic and applied biological research, but the genetic diversity of the study individuals is rarely quantified. University-housed colonies tend to be small and subject to founder effects and genetic drift; so they may be highly inbred or show substantial genetic divergence from other colonies, even those derived from the same source. Disregard for the levels of genetic diversity in an animal colony may result in a failure to replicate results if a different colony is used to repeat an experiment, as different colonies may have fixed alternative variants. Here we use high throughput sequencing to demonstrate genetic divergence in three isolated colonies of Mongolian gerbil (Meriones unguiculatus) even though they were all established recently from the same source. We also show that genetic diversity in allegedly “outbred” colonies of nonmodel rodents (gerbils, hamsters, house mice, deer mice, and rats) varies considerably from nearly no segregating diversity to very high levels of polymorphism. We conclude that genetic divergence in isolated colonies may play an important role in the “replication crisis.” In a more positive light, divergent rodent colonies represent an opportunity to leverage genetically distinct individuals in genetic crossing experiments. In sum, awareness of the genetic diversity of an animal colony is paramount as it allows researchers to properly replicate experiments and also to capitalize on other genetically distinct individuals to explore the genetic basis of a trait. PMID:29242387

Outcomes and Acute Toxicities of Proton Therapy for Pediatric Atypical Teratoid/Rhabdoid Tumor of the Central Nervous System

International Nuclear Information System (INIS)

McGovern, Susan L.; Okcu, M. Fatih; Munsell, Mark F.; Kumbalasseriyil, Nancy; Grosshans, David R.; McAleer, Mary F.; Chintagumpala, Murali; Khatua, Soumen; Mahajan, Anita

2014-01-01

Purpose: Atypical teratoid/rhabdoid tumor (AT/RT) of the central nervous system is a rare cancer primarily affecting children younger than 5 years old. Because patients are young and receive intensive chemotherapy, there is concern regarding late radiation toxicity, particularly as survival rates improve. Therefore, there is interest in using proton therapy to treat these tumors. This study was undertaken to investigate outcomes and acute toxicities associated with proton therapy for AT/RT. Methods and Materials: The records of 31 patients with AT/RT treated with proton radiation from October 2008 to August 2013 were reviewed. Demographics, treatment characteristics, and outcomes were recorded and analyzed. Results: Median age at diagnosis was 19 months (range, 4-55 months), with a median age at radiation start of 24 months (range, 6-62 months). Seventeen patients received local radiation with a median dose of 50.4 GyRBE (range, 9-54 GyRBE). Fourteen patients received craniospinal radiation; half received 24 GyRBE or less, and half received 30.6 GyRBE or more. For patients receiving craniospinal radiation, the median tumor dose was 54 GyRBE (range, 43.2-55.8 GyRBE). Twenty-seven patients (87%) completed the planned radiation. With median follow-up of 24 months for all patients (range, 3-53 months), median progression-free survival was 20.8 months and median overall survival was 34.3 months. Five patients (16%) developed clinical findings and imaging changes in the brainstem 1 to 4 months after radiation, consistent with radiation reaction; all cases resolved with steroids or bevacizumab. Conclusions: This is the largest report of children with AT/RT treated with proton therapy. Preliminary survival outcomes in this young pediatric population are encouraging compared to historic results, but further study is warranted

Outcomes and Acute Toxicities of Proton Therapy for Pediatric Atypical Teratoid/Rhabdoid Tumor of the Central Nervous System

Energy Technology Data Exchange (ETDEWEB)

McGovern, Susan L., E-mail: slmcgove@mdanderson.org [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Okcu, M. Fatih [Texas Children' s Hematology and Oncology Centers, Department of Pediatrics, Baylor College of Medicine, Houston, Texas (United States); Munsell, Mark F. [Department of Biostatistics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Kumbalasseriyil, Nancy; Grosshans, David R.; McAleer, Mary F. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Chintagumpala, Murali [Texas Children' s Hematology and Oncology Centers, Department of Pediatrics, Baylor College of Medicine, Houston, Texas (United States); Khatua, Soumen [Department of Pediatrics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Mahajan, Anita [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

2014-12-01

Purpose: Atypical teratoid/rhabdoid tumor (AT/RT) of the central nervous system is a rare cancer primarily affecting children younger than 5 years old. Because patients are young and receive intensive chemotherapy, there is concern regarding late radiation toxicity, particularly as survival rates improve. Therefore, there is interest in using proton therapy to treat these tumors. This study was undertaken to investigate outcomes and acute toxicities associated with proton therapy for AT/RT. Methods and Materials: The records of 31 patients with AT/RT treated with proton radiation from October 2008 to August 2013 were reviewed. Demographics, treatment characteristics, and outcomes were recorded and analyzed. Results: Median age at diagnosis was 19 months (range, 4-55 months), with a median age at radiation start of 24 months (range, 6-62 months). Seventeen patients received local radiation with a median dose of 50.4 GyRBE (range, 9-54 GyRBE). Fourteen patients received craniospinal radiation; half received 24 GyRBE or less, and half received 30.6 GyRBE or more. For patients receiving craniospinal radiation, the median tumor dose was 54 GyRBE (range, 43.2-55.8 GyRBE). Twenty-seven patients (87%) completed the planned radiation. With median follow-up of 24 months for all patients (range, 3-53 months), median progression-free survival was 20.8 months and median overall survival was 34.3 months. Five patients (16%) developed clinical findings and imaging changes in the brainstem 1 to 4 months after radiation, consistent with radiation reaction; all cases resolved with steroids or bevacizumab. Conclusions: This is the largest report of children with AT/RT treated with proton therapy. Preliminary survival outcomes in this young pediatric population are encouraging compared to historic results, but further study is warranted.

Clinical results of proton beam therapy for skull base chordoma

International Nuclear Information System (INIS)

Igaki, Hiroshi; Tokuuye, Koichi; Okumura, Toshiyuki; Sugahara, Shinji; Kagei, Kenji; Hata, Masaharu; Ohara, Kiyoshi; Hashimoto, Takayuki; Tsuboi, Koji; Takano, Shingo; Matsumura, Akira; Akine, Yasuyuki

2004-01-01

Purpose: To evaluate clinical results of proton beam therapy for patients with skull base chordoma. Methods and materials: Thirteen patients with skull base chordoma who were treated with proton beams with or without X-rays at the University of Tsukuba between 1989 and 2000 were retrospectively reviewed. A median total tumor dose of 72.0 Gy (range, 63.0-95.0 Gy) was delivered. The patients were followed for a median period of 69.3 months (range, 14.6-123.4 months). Results: The 5-year local control rate was 46.0%. Cause-specific, overall, and disease-free survival rates at 5 years were 72.2%, 66.7%, and 42.2%, respectively. The local control rate was higher, without statistical significance, for those with preoperative tumors <30 mL. Partial or subtotal tumor removal did not yield better local control rates than for patients who underwent biopsy only as the latest surgery. Conclusion: Proton beam therapy is effective for patients with skull base chordoma, especially for those with small tumors. For a patient with a tumor of <30 mL with no prior treatment, biopsy without tumor removal seems to be appropriate before proton beam therapy

Latin America: Essays Interpretating Colonial Legacy

Directory of Open Access Journals (Sweden)

María Pia López

2013-12-01

Full Text Available A large part of the Latin–American literature of the 19th and 20th century tried to deal with the national question intertwining different dimensions: the weight of colonial legacy, the cultural peculiarity of the nation and the inner relations between social classes and ethnic groups. Thinking the nation implied, in any case, to think the difference and the conflict with others, as well as the inner conflict and the logic of local colonialism. Analyzing some of these essays that played a central role in such process of recasting the origin of the nation, the author moves around three main axes: the formulation of dualist writings (colonial/national; white /indigenous; civilization/wilderness, the issue of language (the language inherited from the colonial experience versus the multilingual nature of indigenous Latin American societies, and the hypothesis about the birth of the nation – appointed to different groups – and its normal functioning as legitimization of the order sprung from independences.

Proton imaging apparatus for proton therapy application

International Nuclear Information System (INIS)

Sipala, V.; Lo Presti, D.; Brianzi, M.; Civinini, C.; Bruzzi, M.; Scaringella, M.; Talamonti, C.; Bucciolini, M.; Cirrone, G.A.P.; Cuttone, G.; Randazzo, N.; Stancampiano, C.; Tesi, M.

2011-01-01

Radiotherapy with protons, due to the physical properties of these particles, offers several advantages for cancer therapy as compared to the traditional radiotherapy and photons. In the clinical use of proton beams, a p CT (Proton Computer Tomography) apparatus can contribute to improve the accuracy of the patient positioning and dose distribution calculation. In this paper a p CT apparatus built by the Prima (Proton Imaging) Italian Collaboration will be presented and the preliminary results will be discussed.

21 CFR 866.2180 - Manual colony counter.

Science.gov (United States)

2010-04-01

...) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2180 Manual colony counter. (a) Identification. A manual colony counter is a device intended for medical purposes that consists...

Protons and how they are transported by proton pumps

DEFF Research Database (Denmark)

Buch-Pedersen, Morten Jeppe; Pedersen, Bjørn Panyella; Veierskov, Bjarke

2008-01-01

The very high mobility of protons in aqueous solutions demands special features of membrane proton transporters to sustain efficient yet regulated proton transport across biological membranes. By the use of the chemical energy of ATP, plasma-membrane-embedded ATPases extrude protons from cells...... of plants and fungi to generate electrochemical proton gradients. The recently published crystal structure of a plasma membrane H(+)-ATPase contributes to our knowledge about the mechanism of these essential enzymes. Taking the biochemical and structural data together, we are now able to describe the basic...... molecular components that allow the plasma membrane proton H(+)-ATPase to carry out proton transport against large membrane potentials. When divergent proton pumps such as the plasma membrane H(+)-ATPase, bacteriorhodopsin, and F(O)F(1) ATP synthase are compared, unifying mechanistic premises for biological...

Colonial Army Formats in Africa and Post-Colonial Military Coups:

African Journals Online (AJOL)

BSOS USER

The centralised and autocratic features of Caliphate rule were .... latter's participation in the affairs of their respective societies, and leadership ..... deployment of the army by the NPC for internal colonial-style repression duties in the Middle Belt ...

Phase I/II Trial of Hyperfractionated Concomitant Boost Proton Radiotherapy for Supratentorial Glioblastoma Multiforme

International Nuclear Information System (INIS)

Mizumoto, Masashi; Tsuboi, Koji; Igaki, Hiroshi; Yamamoto, Tetsuya; Takano, Shingo; Oshiro, Yoshiko; Hayashi, Yasutaka; Hashii, Haruko; Kanemoto, Ayae; Nakayama, Hidetsugu; Sugahara, Shinji; Sakurai, Hideyuki; Matsumura, Akira; Tokuuye, Koichi

2010-01-01

Purpose: To evaluate the safety and efficacy of postoperative hyperfractionated concomitant boost proton radiotherapy with nimustine hydrochloride for supratentorial glioblastoma multiforme (GBM). Methods and Materials: Twenty patients with histologically confirmed supratentorial GBM met the following criteria: (1) a Karnofsky performance status of ≥60; (2) the diameter of the enhanced area before radiotherapy was ≤40 cm; and (3) the enhanced area did not extend to the brain stem, hypothalamus, or thalamus. Magnetic resonance imaging (MRI) T 2 -weighted high area (clinical tumor volume 3 [CTV3]) was treated by x-ray radiotherapy in the morning (50.4 Gy in 28 fractions). More than 6 hours later, 250 MeV proton beams were delivered to the enhanced area plus a 10-mm margin (CTV2) in the first half of the protocol (23.1 GyE in 14 fractions) and to the enhanced volume (CTV1) in the latter half (23.1 GyE in 14 fraction). The total dose to the CTV1 was 96.6 GyE. Nimustine hydrochloride (80 mg/m2) was administered during the first and fourth weeks. Results: Acute toxicity was mainly hematologic and was controllable. Late radiation necrosis and leukoencephalopathy were each seen in one patient. The overall survival rates after 1 and 2 years were 71.1% and 45.3%, respectively. The median survival period was 21.6 months. The 1- and 2-year progression-free survival rates were 45.0% and 15.5%, respectively. The median MRI change-free survival was 11.2 months. Conclusions: Hyperfractionated concomitant boost proton radiotherapy (96.6 GyE in 56 fractions) for GBM was tolerable and beneficial if the target size was well considered. Further studies are warranted to pursue the possibility of controlling border region recurrences.

Post-Colonialism Perspectives on Educational Competition

Science.gov (United States)

Yeh, Chuan-Rong

2016-01-01

Educational competition has always been the puzzle issue of educational researches. In this article, I analyze several aspects of educational competition within the perspective of post-colonialism discourse. In the political aspect, Taiwanese education is linked with political power, to present the post-colonial spirit by continuing dynastic…

Radioprotective effect of colony-stimulating factor on mice irradiated with 60Co γ-rays

International Nuclear Information System (INIS)

Zhang Junning; Wang Tao; Xu Changshao; Wang Hongyun

1995-01-01

Adult male mice were irradiated with γ-rays 6 Gy once or 3 Gy three times in 7 days and intraperitoneally injected with colony-stimulating factor (CSF) in high doses or low doses. Mice of the control group were injected with normal saline only. Within 30 days after irradiation, the survival rate of mice irradiated with 6 Gy γ-rays once and treated with high dose CSF was 9/25, while that in the control group was 2/25. The survival rate of mice irradiated with 3 Gy three times and treated with high dose CSF was 10/13, while that in the control group was 4/13. Moreover, the survival times of both irradiated groups treated with high dose CSF were much longer than the control groups (p<0.01). This experiment also showed that CSF could reduce the lowering of peripheral blood white blood cell counts and promote their recovery. The number of CFU-S in mice treated with CSF was much higher (23.8 +- 4.82) than in the control group (9.4 +- 4.39) (p<0.01). Therefore, CSF could recover and reconstruct the hematopoietic function of bone marrow, and prolong the survival of irradiated mice

Influence of radiation fractionation on survival of mice and spleen colony-forming units

International Nuclear Information System (INIS)

Cronkite, E.P.; Bullis, J.E.

1994-01-01

C57B1/6 mice were given Gy X-rays fractionated in several ways. There was a cyclical pattern of animal survival which was correlated to the fractionation interval and which indicated a periodicity of 6 h. Ten grays given a single dose is fatal to 100% of the mice and depresses the CFU-S to about one per leg with no evidence of proliferation during the remaining life. Ten grays given in 2.5-Gy increments at 24-h intervals causes no fatalities and results in a similar CFU-S depression but is followed by an exponential increase in CFU-S over the ensuing 12 days. Although bone marrow from survivors of such treatment was comparable to control marrow in its capacity for short-term rescue, it was clearly, inferior in its capability for long-term rescue. The periodicity of 6 h suggests that the cells responsible for survival of the mice have been synchronized into more or less radiosensitive and radioresistant stages of the cell cycle as a result of the time between the 25-Gy increments. Implications for the CFU-S and long-term repopulating cells are discussed. 22 refs., 5 figs., 1 tab

Measurement of small-angle antiproton-proton and proton-proton elastic scattering at the CERN intersecting storage rings

NARCIS (Netherlands)

Amos, N.; Block, M.M.; Bobbink, G.J.; Botje, M.A.J.; Favart, D.; Leroy, C.; Linde, F.; Lipnik, P.; Matheys, J-P.; Miller, D.

1985-01-01

Antiproton-proton and proton-proton small-angle elastic scattering was measured for centre-of-mass energies at the CERN Intersectung Storage Rings. In addition, proton-proton elastic scattering was measured at . Using the optical theorem, total cross sections are obtained with an accuracy of about

Colony Development and Density-Dependent Processes in Breeding Grey Herons

Directory of Open Access Journals (Sweden)

Takeshi Shirai

2013-01-01

Full Text Available The density-dependent processes that limit the colony size of colonially breeding birds such as herons and egrets remain unclear, because it is difficult to monitor colonies from the first year of their establishment, and the most previous studies have considered mixed-species colonies. In the present study, single-species colonies of the Grey Heron (Ardea cinerea were observed from the first year of their establishment for 16 years in suburban Tokyo. Colony size increased after establishment, illustrating a saturation curve. The breeding duration (days from nest building to fledging by a pair increased, but the number of fledglings per nest decreased, with colony size. The reproductive season in each year began earlier, and there was greater variation in the timing of individual breeding when the colony size was larger. The prolonged duration until nestling feeding by early breeders of the colony suggests that herons at the beginning of the new breeding season exist in an unsteady state with one another, likely owing to interactions with immigrant individuals. Such density-dependent interference may affect reproductive success and limit the colony size of Grey Herons.

Queen promiscuity lowers disease within honeybee colonies

OpenAIRE

Seeley, Thomas D; Tarpy, David R

2006-01-01

Most species of social insects have singly mated queens, but in some species each queen mates with numerous males to create a colony with a genetically diverse worker force. The adaptive significance of polyandry by social insect queens remains an evolutionary puzzle. Using the honeybee (Apis mellifera), we tested the hypothesis that polyandry improves a colony's resistance to disease. We established colonies headed by queens that had been artificially inseminated by either one or 10 drones. ...

Effect of fluid motion on colony formation in Microcystis aeruginosa

Directory of Open Access Journals (Sweden)

Lin Li

2013-01-01

Full Text Available Microcystis aeruginosa, generally occurring in large colonies under natural conditions, mainly exists as single cells in laboratory cultures. The mechanisms involved in colony formation in Microcystis aeruginosa and their roles in algal blooms remain unknown. In this study, based on previous research findings that fluid motion may stimulate the colony formation in green algae, culture experiments were conducted under axenic conditions in a circular water chamber where the flow rate, temperature, light, and nutrients were controlled. The number of cells of Microcystis aeruginosa, the number of cells per colony, and the colonial characteristics in various growth phases were observed and measured. The results indicated that the colony formation in Microcystis aeruginosa, which was not observed under stagnant conditions, was evident when there was fluid motion, with the number of cells per largest colony reaching 120 and the proportion of the number of cells in colonial form to the total number of cells and the mean number of cells per colony reaching their peak values at a flow rate of 35 cm/s. Based on the analysis of colony formation process, fluid motion stimulates the colony formation in Microcystis aeruginosa in the lag growth phase, while flushes and disaggregates the colonies in the exponential growth phase. The stimulation effect in the lag growth phase may be attributable to the involvement of fluid motion in a series of physiological processes, including the uptake of trace elements and the synthesis and secretion of polysaccharides. In addition, the experimental groups exhibiting typical colonial characteristics in the lag growth phase were found to have higher cell biomass in the later phase.

On proton CT reconstruction using MVCT-converted virtual proton projections

Energy Technology Data Exchange (ETDEWEB)

Wang Dongxu; Mackie, T. Rockwell; Tome, Wolfgang A. [Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53705 and Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, Iowa 52242 (United States); Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53705 and Morgridge Institute of Research, University of Wisconsin, Madison, Wisconsin 53715 (United States); Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53705 and Oncophysics Institute, Albert Einstein College of Medicine, Yeshiva University, Bronx, New York 10461 (United States)

2012-06-15

Purpose: To describe a novel methodology of converting megavoltage x-ray projections into virtual proton projections that are otherwise missing due to the proton range limit. These converted virtual proton projections can be used in the reconstruction of proton computed tomography (pCT). Methods: Relations exist between proton projections and multispectral megavoltage x-ray projections for human tissue. Based on these relations, these tissues can be categorized into: (a) adipose tissue; (b) nonadipose soft tissues; and (c) bone. These three tissue categories can be visibly identified on a regular megavoltage x-ray computed tomography (MVCT) image. With an MVCT image and its projection data available, the x-ray projections through heterogeneous anatomy can be converted to the corresponding proton projections using predetermined calibration curves for individual materials, aided by a coarse segmentation on the x-ray CT image. To show the feasibility of this approach, mathematical simulations were carried out. The converted proton projections, plotted on a proton sinogram, were compared to the simulated ground truth. Proton stopping power images were reconstructed using either the virtual proton projections only or a blend of physically available proton projections and virtual proton projections that make up for those missing due to the range limit. These images were compared to a reference image reconstructed from theoretically calculated proton projections. Results: The converted virtual projections had an uncertainty of {+-}0.8% compared to the calculated ground truth. Proton stopping power images reconstructed using a blend of converted virtual projections (48%) and physically available projections (52%) had an uncertainty of {+-}0.86% compared with that reconstructed from theoretically calculated projections. Reconstruction solely from converted virtual proton projections had an uncertainty of {+-}1.1% compared with that reconstructed from theoretical projections

On proton CT reconstruction using MVCT-converted virtual proton projections

International Nuclear Information System (INIS)

Wang Dongxu; Mackie, T. Rockwell; Tomé, Wolfgang A.

2012-01-01

Purpose: To describe a novel methodology of converting megavoltage x-ray projections into virtual proton projections that are otherwise missing due to the proton range limit. These converted virtual proton projections can be used in the reconstruction of proton computed tomography (pCT). Methods: Relations exist between proton projections and multispectral megavoltage x-ray projections for human tissue. Based on these relations, these tissues can be categorized into: (a) adipose tissue; (b) nonadipose soft tissues; and (c) bone. These three tissue categories can be visibly identified on a regular megavoltage x-ray computed tomography (MVCT) image. With an MVCT image and its projection data available, the x-ray projections through heterogeneous anatomy can be converted to the corresponding proton projections using predetermined calibration curves for individual materials, aided by a coarse segmentation on the x-ray CT image. To show the feasibility of this approach, mathematical simulations were carried out. The converted proton projections, plotted on a proton sinogram, were compared to the simulated ground truth. Proton stopping power images were reconstructed using either the virtual proton projections only or a blend of physically available proton projections and virtual proton projections that make up for those missing due to the range limit. These images were compared to a reference image reconstructed from theoretically calculated proton projections. Results: The converted virtual projections had an uncertainty of ±0.8% compared to the calculated ground truth. Proton stopping power images reconstructed using a blend of converted virtual projections (48%) and physically available projections (52%) had an uncertainty of ±0.86% compared with that reconstructed from theoretically calculated projections. Reconstruction solely from converted virtual proton projections had an uncertainty of ±1.1% compared with that reconstructed from theoretical projections. If

Structural organisation and dynamics in king penguin colonies

Science.gov (United States)

Gerum, Richard; Richter, Sebastian; Fabry, Ben; Le Bohec, Céline; Bonadonna, Francesco; Nesterova, Anna; Zitterbart, Daniel P.

2018-04-01

During breeding, king penguins do not build nests, however they show strong territorial behaviour and keep a pecking distance to neighbouring penguins. Penguin positions in breeding colonies are highly stable over weeks and appear regularly spaced, but thus far no quantitative analysis of the structural order inside a colony has been performed. In this study, we use the radial distribution function to analyse the spatial coordinates of penguin positions. Coordinates are obtained from aerial images of two colonies that were observed for several years. Our data demonstrate that the structural order in king penguin colonies resembles a 2D liquid of particles with a Lennard-Jones-type interaction potential. We verify this using a molecular dynamics simulation with thermally driven particles, whereby temperature corresponds to penguin movements, the energy well depth ɛ of the attractive potential corresponds to the strength of the colony-forming behaviour, and the repulsive zone corresponds to the pecking radius. We can recapitulate the liquid disorder of the colony, as measured by the radial distribution function, when the particles have a temperature of several (1.4–10) \

WE-H-BRA-05: Investigation of LET Spectral Dependence of the Biological Effects of Therapeutic Protons

Energy Technology Data Exchange (ETDEWEB)

Guan, F; Bronk, L; Kerr, M; Wang, X; Li, Y; Peeler, C; Sahoo, N; Patel, D; Mirkovic, D; Titt, U; Grosshans, D; Mohan, R [UT MD Anderson Cancer Center, Houston, TX (United States)

2016-06-15

Purpose: To investigate the dependence of biologic effect (BE) of therapeutic protons on LET spectra by comparing BEs with equal dose-averaged LET (LETd) derived from different LET spectra using high-throughput in vitro clonogenic survival assays. Methods: We used Geant4 to design the relevant experimental setups and perform the dose, LETd, and LET spectra calculations for spot-scanning protons. The clonogenic assay was performed using the H460 lung cancer cell line cultured in 96-well plates. In the first experimental setup (S1), cells were irradiated using 127.4 MeV protons with a 93.22 mm Lucite buildup resulting in a LETd value of 3.4 keV/µm in the cell layer. In the second experimental setup (S2), cells were irradiated by a combination of 127.4 MeV and 136.4 MeV protons with a 96.61 mm Lucite buildup. The LETd values in the cell layer were 11.4 keV/µm and 1.5 keV/µm respectively, but an average LETd of 3.4 keV/µm was obtained by adjusting the relative fluence of each beam. Ten discrete dose levels with 0.5 Gy increments were delivered. Results: In the two setups, the energies or LET spectra were different but resulted in identical LETd values. We quantified the dose contributions from high-LET (≥10 keV/µm, threshold determined by previous experiments) events in the LET spectra separately for these two setups as 3.2% and 10.5%. The biologic effects at each identical dose level yielded statistically significant different survival curves (extra sum-of-squares F-test, P<0.0001). The second setup with a higher contribution from high-LET events exhibited the higher biologic effect with a dose enhancement factor of 1.17±0.03 at 0.10 surviving fraction. Conclusion: The dose-averaged LET may not be an accurate indicator of the biological effects of protons. Detailed LET spectra may need to be considered explicitly to accurately quantify the biologic effects of protons. Funding Support: U19 CA021239-35, R21 CA187484-01 and MDACC-IRG.

Reirradiation of Recurrent and Second Primary Head and Neck Cancer With Proton Therapy

Energy Technology Data Exchange (ETDEWEB)

McDonald, Mark W., E-mail: mark.mcdonald@emory.edu [Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, Georgia (United States); Zolali-Meybodi, Omid; Lehnert, Stephen J. [Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, Indiana (United States); Estabrook, Neil C. [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana (United States); Liu, Yuan [Department of Biostatistics and Bioinformatics, Rollins School of Public Health of Emory University, Atlanta, Georgia (United States); Cohen-Gadol, Aaron A. [Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, Indiana (United States); Moore, Michael G. [Department of Otolaryngology–Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, Indiana (United States)

2016-11-15

Purpose: To report the clinical outcomes of head and neck reirradiation with proton therapy. Methods and Materials: From 2004 to 2014, 61 patients received curative-intent proton reirradiation, primarily for disease involving skull base structures, at a median of 23 months from the most recent previous course of radiation. Most had squamous cell (52.5%) or adenoid cystic (16.4%) carcinoma. Salvage surgery before reirradiation was undertaken in 47.5%. Gross residual disease was present in 70.5%. For patients with microscopic residual disease, the median dose of reirradiation was 66 Gy (relative biological effectiveness), and for gross disease was 70.2 Gy (relative biological effectiveness). Concurrent chemotherapy was given in 27.9%. Results: The median follow-up time was 15.2 months and was 28.7 months for patients remaining alive. The 2-year overall survival estimate was 32.7%, and the median overall survival was 16.5 months. The 2-year cumulative incidence of local failure with death as a competing risk was 19.7%; regional nodal failure, 3.3%; and distant metastases, 38.3%. On multivariable analysis, Karnofsky performance status ≤70%, the presence of a gastrostomy tube before reirradiation, and an increasing number of previous courses of radiation therapy were associated with a greater hazard ratio for death. A cutaneous primary tumor, gross residual disease, increasing gross tumor volume, and a lower radiation dose were associated with a greater hazard ratio for local failure. Grade ≥3 toxicities were seen in 14.7% acutely and 24.6% in the late setting, including 3 treatment-related deaths. Conclusions: Reirradiation with proton therapy, with or without chemotherapy, provided reasonable locoregional disease control, toxicity profiles, and survival outcomes for an advanced-stage and heavily pretreated population. Additional data are needed to identify which patients are most likely to benefit from aggressive efforts to achieve local disease control and

Colonial army recruitment patterns and post-colonial Military Coups ...

African Journals Online (AJOL)

Since time immemorial, societies, states and state builders have been challenged and transformed by the need and quest for military manpower. European states relied on conscript armies to 'pacify' and retain colonies in parts of the non-European world. These facts underscore the meticulous attention paid by the British to ...

Ant- and Ant-Colony-Inspired ALife Visual Art.

Science.gov (United States)

Greenfield, Gary; Machado, Penousal

2015-01-01

Ant- and ant-colony-inspired ALife art is characterized by the artistic exploration of the emerging collective behavior of computational agents, developed using ants as a metaphor. We present a chronology that documents the emergence and history of such visual art, contextualize ant- and ant-colony-inspired art within generative art practices, and consider how it relates to other ALife art. We survey many of the algorithms that artists have used in this genre, address some of their aims, and explore the relationships between ant- and ant-colony-inspired art and research on ant and ant colony behavior.

The Role of Non-Foraging Nests in Polydomous Wood Ant Colonies.

Science.gov (United States)

Ellis, Samuel; Robinson, Elva J H

2015-01-01

A colony of red wood ants can inhabit more than one spatially separated nest, in a strategy called polydomy. Some nests within these polydomous colonies have no foraging trails to aphid colonies in the canopy. In this study we identify and investigate the possible roles of non-foraging nests in polydomous colonies of the wood ant Formica lugubris. To investigate the role of non-foraging nests we: (i) monitored colonies for three years; (ii) observed the resources being transported between non-foraging nests and the rest of the colony; (iii) measured the amount of extra-nest activity around non-foraging and foraging nests. We used these datasets to investigate the extent to which non-foraging nests within polydomous colonies are acting as: part of the colony expansion process; hunting and scavenging specialists; brood-development specialists; seasonal foragers; or a selfish strategy exploiting the foraging effort of the rest of the colony. We found that, rather than having a specialised role, non-foraging nests are part of the process of colony expansion. Polydomous colonies expand by founding new nests in the area surrounding the existing nests. Nests founded near food begin foraging and become part of the colony; other nests are not founded near food sources and do not initially forage. Some of these non-foraging nests eventually begin foraging; others do not and are abandoned. This is a method of colony growth not available to colonies inhabiting a single nest, and may be an important advantage of the polydomous nesting strategy, allowing the colony to expand into profitable areas.

Between Past and Present: The Sociopsychological Constructs of Colonialism, Coloniality and Postcolonialism.

Science.gov (United States)

Tomicic, Ana; Berardi, Filomena

2018-03-01

If one of the major aspirations of postcolonial theory is to re-establish a balance in the relationship between the (former) colonizer and the colonized by engaging the voices of the "subaltern", and on the other hand to illuminate how power relations of the present are embedded in history (Mills 2007), we argue that important theoretical insights might inform research by anchoring post-colonial theory within a sociopsychological framework. While there is a growing corpus of sociopsychological research articles focusing on how major geopolitical events and historical processes bear on people's lives, we aim to investigate the theoretical potential of postcolonial theory within the disciplines aiming at a sociopsychological approach. By focusing on the social dynamics of power imbalances, post-colonial theory finds its operational meaning: the feelings stemming from actions committed in the past are indeed crucial in determining reparatory attitudes and policies towards members of former colonized groups. Firstly, drawing from the sociopsychological scientific production related to consequences of colonial past, seen in recent years as a growing research interest in the field, we will explore patterns and trends through a thematic analysis of literature. Social Psychology as well as adjacent disciplines can greatly benefit from this theoretical fertilization, especially in the way post-colonial ideologies relate to the symbolic promotion versus exclusion of indigenous culture (Sengupta et al., International Journal of Intercultural Relations, 36(4), 506-517, 2012). Furthermore, by comparing and contrasting the ideological cosmologies relating to this particular topic, this study aims to establish the state of knowledge in the field, to identify how research methods and thematic fields are paired, to find "gaps" and create spaces for research that become integrative of postcolonial theory. While focusing on academic production, we also hope to contribute to develop

Colony strength and queen replacement in Melipona marginata (Apidae: Meliponini

Directory of Open Access Journals (Sweden)

A. de M. P. Kleinert

Full Text Available Physogastric queens of Melipona marginata were removed from their colonies in order to verify the acceptance of a new queen by workers. Colony strength was evaluated according to queen oviposition rate and comb diameters. Replacement was observed seven times. Its occurrence and speed related positively to colony strength, independently of queen's age. In weak colonies, queen replacement was observed only once, following colony population increase that occurred after introduction of combs from another colony. Worker oviposition after queen removal was observed three times: in a strong colony with virgin queens and males, and in two of the weak colonies. In the first two or three days of new queen oviposition, during which most of the eggs were eaten by the queen, worker oviposition preceded almost all provisioning and oviposition processes (POPs. After this period, worker oviposition decreased until it reached around 25% of the POPs. Daily oviposition rate of young queens decreased or was even interrupted by hatching of their first brood.

Colonial Bilingual Heritage and Post-Colonial Myths in Cameroon's ...

African Journals Online (AJOL)

Thus, the study traces and shows that an uncritical support of the existing school bilingualism, a aspect of the general political objective of national unity and integration, hinges on a fictitious collective post-colonial dream about using the bilingual heritage of French and English, and the cultures that lie behind them, ...

California gull chicks raised near colony edges have elevated stress levels

Science.gov (United States)

Herring, Garth; Ackerman, Joshua T.

2011-01-01

Coloniality in nesting birds represents an important life history strategy for maximizing reproductive success. Birds nesting near the edge of colonies tend to have lower reproductive success than individuals nesting near colony centers, and offspring of edge-nesting parents may be impaired relative to those of central-nesting parents. We used fecal corticosterone metabolites in California gull chicks (Larus californicus) to examine whether colony size or location within the colony influenced a chick's physiological condition. We found that chicks being raised near colony edges had higher fecal corticosterone metabolite concentrations than chicks raised near colony centers, but that colony size (ranging from 150 to 11,554 nests) had no influence on fecal corticosterone levels. Fecal corticosterone metabolite concentrations also increased with chick age. Our results suggest that similarly aged California gull chicks raised near colony edges may be more physiologically stressed, as indicated by corticosterone metabolites, than chicks raised near colony centers.

Vacuolar-proton-ATPase is involved in the response of cancer cells to ionizing radiation and is a new target for radiosensitization

International Nuclear Information System (INIS)

Hollister, T.C.; Paglin, S.; McMahill, M.S.; Gilles, F.; Yahalom, J.

2001-01-01

Purpose: We have recently described a novel response of human cancer cells to radiation consisting of accumulation of acidic vesicular organelles (AVO) (Cancer Research, 61:439-444, 2001). Acidification of AVO was inhibited by bafilomycin A1 - a specific inhibitor of vacuolar-proton-ATPase. To examine the role of AVO function in the cellular response to radiation, we determined the effect of specific inhibitors of v-H+-ATPase (bafilomycin and concanamycin) on the clonogenic survival of various cancer cell lines. In addition, Northern analysis of mRNA encoding v-H+-ATPase was performed to elucidate possible mechanisms of post-radiation v-H+-ATPase regulation. Materials and Methods: Total RNA was isolated from human cancer cell lines including MCF-7 (breast), LoVo (colon), and LNCaP (prostate) cells 48 hours post-irradiation, and Northern analyses were performed. RNA was separated on a denaturing formaldehyde gel and blotted to a nylon membrane. Probes made from cDNAs to v-H+-ATPase were radioactively labeled, hybridized to the membranes, and exposed to X-ray film for determination of mRNA expression levels. Clonogenic survival assays were performed with MCF-7 and LoVo cell lines. Cells were plated at 30 cells/cm 2 , and irradiated 24 hours post-plating. Bafilomycin or concanamycin were added to culture media in various concentrations at the time of irradiation. The media was changed after a 24-hour incubation, and colonies were stained with crystal violet for counting 7 days post-irradiation. Results: Radiation-induced accumulation of acidic vesicular organelles in MCF-7, LoVo and LNCaP cells was associated with a two-fold increase in the steady-state level of mRNA for subunit c of v-H+-ATPase. Bafilomycin and concanamycin increased clonogenic cell death after irradiation in a dose-dependent manner. At low concentrations (bafilomycin 2nM, concanamycin 2pM) these agents acted as radiosensitizers, without significant toxicity to unirradiated cells. At 2nM, bafilomycin

Experimental Study for Automatic Colony Counting System Based Onimage Processing

Science.gov (United States)

Fang, Junlong; Li, Wenzhe; Wang, Guoxin

Colony counting in many colony experiments is detected by manual method at present, therefore it is difficult for man to execute the method quickly and accurately .A new automatic colony counting system was developed. Making use of image-processing technology, a study was made on the feasibility of distinguishing objectively white bacterial colonies from clear plates according to the RGB color theory. An optimal chromatic value was obtained based upon a lot of experiments on the distribution of the chromatic value. It has been proved that the method greatly improves the accuracy and efficiency of the colony counting and the counting result is not affected by using inoculation, shape or size of the colony. It is revealed that automatic detection of colony quantity using image-processing technology could be an effective way.

Rapidity gap survival in the black-disk regime

International Nuclear Information System (INIS)

Leonid Frankfurt; Charles Hyde; Mark Strikman; Christian Weiss

2007-01-01

We summarize how the approach to the black-disk regime (BDR) of strong interactions at TeV energies influences rapidity gap survival in exclusive hard diffraction pp -> p + H + p (H = dijet, Qbar Q, Higgs). Employing a recently developed partonic description of such processes, we discuss (a) the suppression of diffraction at small impact parameters by soft spectator interactions in the BDR; (b) further suppression by inelastic interactions of hard spectator partons in the BDR; (c) effects of correlations between hard and soft interactions, as suggested by various models of proton structure (color fluctuations, spatial correlations of partons). Hard spectator interactions in the BDR substantially reduce the rapidity gap survival probability at LHC energies compared to previously reported estimates

Rapidity gap survival in central exclusive diffraction: Dynamical mechanisms and uncertainties

International Nuclear Information System (INIS)

Strikman, Mark; Weiss, Christian

2009-01-01

We summarize our understanding of the dynamical mechanisms governing rapidity gap survival in central exclusive diffraction, pp -> p + H + p (H = high-mass system), and discuss the uncertainties in present estimates of the survival probability. The main suppression of diffractive scattering is due to inelastic soft spectator interactions at small pp impact parameters and can be described in a mean-field approximation (independent hard and soft interactions). Moderate extra suppression results from fluctuations of the partonic configurations of the colliding protons. At LHC energies absorptive interactions of hard spectator partons associated with the gg -> H process reach the black-disk regime and cause substantial additional suppression, pushing the survival probability below 0.01.

Colony collapse disorder: a descriptive study.

Directory of Open Access Journals (Sweden)

Dennis Vanengelsdorp

Full Text Available BACKGROUND: Over the last two winters, there have been large-scale, unexplained losses of managed honey bee (Apis mellifera L. colonies in the United States. In the absence of a known cause, this syndrome was named Colony Collapse Disorder (CCD because the main trait was a rapid loss of adult worker bees. We initiated a descriptive epizootiological study in order to better characterize CCD and compare risk factor exposure between populations afflicted by and not afflicted by CCD. METHODS AND PRINCIPAL FINDINGS: Of 61 quantified variables (including adult bee physiology, pathogen loads, and pesticide levels, no single measure emerged as a most-likely cause of CCD. Bees in CCD colonies had higher pathogen loads and were co-infected with a greater number of pathogens than control populations, suggesting either an increased exposure to pathogens or a reduced resistance of bees toward pathogens. Levels of the synthetic acaricide coumaphos (used by beekeepers to control the parasitic mite Varroa destructor were higher in control colonies than CCD-affected colonies. CONCLUSIONS/SIGNIFICANCE: This is the first comprehensive survey of CCD-affected bee populations that suggests CCD involves an interaction between pathogens and other stress factors. We present evidence that this condition is contagious or the result of exposure to a common risk factor. Potentially important areas for future hypothesis-driven research, including the possible legacy effect of mite parasitism and the role of honey bee resistance to pesticides, are highlighted.

Iridovirus and microsporidian linked to honey bee colony decline.

Science.gov (United States)

Bromenshenk, Jerry J; Henderson, Colin B; Wick, Charles H; Stanford, Michael F; Zulich, Alan W; Jabbour, Rabih E; Deshpande, Samir V; McCubbin, Patrick E; Seccomb, Robert A; Welch, Phillip M; Williams, Trevor; Firth, David R; Skowronski, Evan; Lehmann, Margaret M; Bilimoria, Shan L; Gress, Joanna; Wanner, Kevin W; Cramer, Robert A

2010-10-06

In 2010 Colony Collapse Disorder (CCD), again devastated honey bee colonies in the USA, indicating that the problem is neither diminishing nor has it been resolved. Many CCD investigations, using sensitive genome-based methods, have found small RNA bee viruses and the microsporidia, Nosema apis and N. ceranae in healthy and collapsing colonies alike with no single pathogen firmly linked to honey bee losses. We used Mass spectrometry-based proteomics (MSP) to identify and quantify thousands of proteins from healthy and collapsing bee colonies. MSP revealed two unreported RNA viruses in North American honey bees, Varroa destructor-1 virus and Kakugo virus, and identified an invertebrate iridescent virus (IIV) (Iridoviridae) associated with CCD colonies. Prevalence of IIV significantly discriminated among strong, failing, and collapsed colonies. In addition, bees in failing colonies contained not only IIV, but also Nosema. Co-occurrence of these microbes consistently marked CCD in (1) bees from commercial apiaries sampled across the U.S. in 2006-2007, (2) bees sequentially sampled as the disorder progressed in an observation hive colony in 2008, and (3) bees from a recurrence of CCD in Florida in 2009. The pathogen pairing was not observed in samples from colonies with no history of CCD, namely bees from Australia and a large, non-migratory beekeeping business in Montana. Laboratory cage trials with a strain of IIV type 6 and Nosema ceranae confirmed that co-infection with these two pathogens was more lethal to bees than either pathogen alone. These findings implicate co-infection by IIV and Nosema with honey bee colony decline, giving credence to older research pointing to IIV, interacting with Nosema and mites, as probable cause of bee losses in the USA, Europe, and Asia. We next need to characterize the IIV and Nosema that we detected and develop management practices to reduce honey bee losses.

Colony mapping: A new technique for monitoring crevice-nesting seabirds

Science.gov (United States)

Renner, H.M.; Renner, M.; Reynolds, J.H.; Harping, A.M.A.; Jones, I.L.; Irons, D.B.; Byrd, G.V.

2006-01-01

Monitoring populations of auklets and other crevice-nesting seabirds remains problematic, although numerous methods have been attempted since the mid-1960s. Anecdotal evidence suggests several large auklet colonies have recently decreased in both abundance and extent, concurrently with vegetation encroachment and succession. Quantifying changes in the geographical extent of auklet colonies may be a useful alternative to monitoring population size directly. We propose a standardized method for colony mapping using a randomized systematic grid survey with two components: a simple presence/absence survey and an auklet evidence density survey. A quantitative auklet evidence density index was derived from the frequency of droppings and feathers. This new method was used to map the colony on St. George Island in the southeastern Bering Sea and results were compared to previous colony mapping efforts. Auklet presence was detected in 62 of 201 grid cells (each grid cell = 2500 m2) by sampling a randomly placed 16 m2 plot in each cell; estimated colony area = 155 000 m2. The auklet evidence density index varied by two orders of magnitude across the colony and was strongly correlated with means of replicated counts of birds socializing on the colony surface. Quantitatively mapping all large auklet colonies is logistically feasible using this method and would provide an important baseline for monitoring colony status. Regularly monitoring select colonies using this method may be the best means of detecting changes in distribution and population size of crevice-nesting seabirds. ?? The Cooper Ornithological Society 2006.

Deconstructive Pedagogy and Ideological Demystification in Post-Colonial Pakistan

Science.gov (United States)

Mansoor, Asma; Malik, Samina

2016-01-01

With post-colonial Pakistan inheriting the British colonial ideological and governmental apparatus, the English literature curriculum implemented at the university level in Pakistan carried the interpellatory baggage of its colonial past. Our interdisciplinary exploration focuses on using deconstructive pedagogy to demystify and subvert the…

Proton beam therapy in the management of skull base chordomas: systematic review of indications, outcomes, and implications for neurosurgeons.

Science.gov (United States)

Matloob, Samir A; Nasir, Haleema A; Choi, David

2016-08-01

Chordomas are rare tumours affecting the skull base. There is currently no clear consensus on the post-surgical radiation treatments that should be used after maximal tumour resection. However, high-dose proton beam therapy is an accepted option for post-operative radiotherapy to maximise local control, and in the UK, National Health Service approval for funding abroad is granted for specific patient criteria. To review the indications and efficacy of proton beam therapy in the management of skull base chordomas. The primary outcome measure for review was the efficacy of proton beam therapy in the prevention of local occurrence. A systematic review of English and non-English articles using MEDLINE (1946-present) and EMBASE (1974-present) databases was performed. Additional studies were reviewed when referenced in other studies and not available on these databases. Search terms included chordoma or chordomas. The PRISMA guidelines were followed for reporting our findings as a systematic review. A total of 76 articles met the inclusion and exclusion criteria for this review. Limitations included the lack of documentation of the extent of primary surgery, tumour size, and lack of standardised outcome measures. Level IIb/III evidence suggests proton beam therapy given post operatively for skull base chordomas results in better survival with less damage to surrounding tissue. Proton beam therapy is a grade B/C recommended treatment modality for post-operative radiation therapy to skull base chordomas. In comparison to other treatment modalities long-term local control and survival is probably improved with proton beam therapy. Further, studies are required to directly compare proton beam therapy to other treatment modalities in selected patients.

The regulation of British colonial lunatic asylums and the origins of colonial psychiatry, 1860-1864.

Science.gov (United States)

Swartz, Sally

2010-05-01

In this paper I outline a brief period in the history of the British Empire, during which colonial lunatic asylum policy began to be formulated. I begin with a scandal that erupted in Jamaica and suggest that this set in motion processes that led to critical changes in asylum administration. The first of these processes was an audit of hospitals and asylums in the colonies. The results of the audit and the policy that emerged from it marked the beginning of systematic regulation of lunatic asylum practice across the British Empire. It revealed a formulation of policy that was intended to cut across the self-governing regimes that had up to this point been allowed to evolve. Drawing on the work of Michel Foucault and Nikolas Rose, I argue that the policy and the practices associated with it contribute to an understanding of the emergence of the psy-sciences in colonial settings. They illustrate the establishment of a panoptic gaze on previously neglected insane spaces. Systematic surveillance constituted government at a distance and made colonial lunacy administration a governable discursive space. The regulation of the medical officers, lunatic attendants, and hospital boards began the process of creating a professional psychiatric workforce. I conclude with a discussion of the implications and the mixed impact of this policy change for the mentally ill across the empire, over the ensuing decades.

Preparation of Single-cohort Colonies and Hormone Treatment of Worker Honeybees to Analyze Physiology Associated with Role and/or Endocrine System.

Science.gov (United States)

Ueno, Takayuki; Kawasaki, Kiyoshi; Kubo, Takeo

2016-09-06

Honeybee workers are engaged in various tasks related to maintaining colony activity. The tasks of the workers change according to their age (age-related division of labor). Young workers are engaged in nursing the brood (nurse bees), while older workers are engaged in foraging for nectar and pollen (foragers). The physiology of the workers changes in association with this role shift. For example, the main function of the hypopharyngeal glands (HPGs) changes from the secretion of major royal jelly proteins (MRJPs) to the secretion of carbohydrate-metabolizing enzymes. Because worker tasks change as the workers age in typical colonies, it is difficult to discriminate the physiological changes that occur with aging from those that occur with the role shift. To study the physiological changes in worker tissues, including the HPGs, in association with the role shift, it would be useful to manipulate the honeybee colony population by preparing single-cohort colonies in which workers of almost the same age perform different tasks. Here we describe a detailed protocol for preparing single-cohort colonies for this analysis. Six to eight days after single-cohort colony preparation, precocious foragers that perform foraging tasks earlier than usual appear in the colony. Representative results indicated role-associated changes in HPG gene expression, suggesting role-associated HPG function. In addition to manipulating the colony population, analysis of the endocrine system is important for investigating role-associated physiology. Here, we also describe a detailed protocol for treating workers with 20-hydroxyecdysone (20E), an active form of ecdysone, and methoprene, a juvenile hormone analogue. The survival rate of treated bees was sufficient to examine gene expression in the HPGs. Gene expression changes were observed in response to 20E- and/or methoprene-treatment, suggesting that hormone treatments induce physiological changes of the HPGs. The protocol for hormone

Leisure, economy and colonial urbanism: Darjeeling, 1835-1930.

Science.gov (United States)

Bhattacharya, Nandini

2013-08-01

This article posits that the hill station of Darjeeling was a unique form of colonial urbanism. It shifts historiographical interest from major urban centres in colonial India (such as Bombay or Calcutta) and instead attempts a greater understanding of smaller urban centres. In the process, it also interrogates the category of hill stations, which have been understood as exotic and scenic sites rather than as towns that were integral to the colonial economy. In arguing that hill stations, particularly Darjeeling, were not merely the scenic and healthy 'other' of the clamorous, dirty and diseased plains of India, it refutes suggestions that the 'despoiling' or overcrowding of Darjeeling was incremental to the purposes of its establishment. Instead, it suggests that Darjeeling was part of the colonial mainstream; its urbanization and inclusion into the greater colonial economy was effected from the time of its establishment. Therefore, a constant tension between its exotic and its functional elements persisted throughout.

Colony formation by sublethally heat-injured Zygosaccharomyces rouxii as affected by solutes in the recovery medium and procedure for sterilizing medium.

Science.gov (United States)

Golden, D A; Beuchat, L R

1990-01-01

Recovery and colony formation by healthy and sublethally heat-injured cells of Zygosaccharomyces rouxii as influenced by the procedure for sterilizing recovery media (YM agar [YMA], wort agar, cornmeal agar, and oatmeal agar) were investigated. Media were supplemented with various concentrations of glucose, sucrose, glycerol, or sorbitol and sterilized by autoclaving (110 degrees C, 15 min) and by repeated treatment with steam (100 degrees C). An increase in sensitivity was observed when heat-injured cells were plated on glucose-supplemented YMA at an aw of 0.880 compared with aws of 0.933 and 0.998. Colonies which developed from unheated and heated cells on YMA at aws of 0.998 and 0.933 generally exceeded 0.5 mm in diameter within 3.5 to 4 days of incubation at 25 degrees C, whereas colonies formed on YMA at an aw of 0.880 typically did not exceed 0.5 mm in diameter until after 5.5 to 6.5 days of incubation. The number of colonies exceeding 0.5 mm in diameter which were formed by heat-injured cells on YMA at an aw of 0.880 was 2 to 3 logs less than the total number of colonies detected, i.e., on YMA at an aw of 0.933 and using no limits of exclusion based on colony diameter. A substantial portion of cells which survived heat treatment were sublethally injured as evidenced by increased sensitivity to a suboptimum aw (0.880). In no instance was recovery of Z. rouxii significantly affected by medium sterilization procedure when glucose or sorbitol was used as the aw-suppressing solute.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2403251

Colony formation by sublethally heat-injured Zygosaccharomyces rouxii as affected by solutes in the recovery medium and procedure for sterilizing medium.

Science.gov (United States)

Golden, D A; Beuchat, L R

1990-08-01

Recovery and colony formation by healthy and sublethally heat-injured cells of Zygosaccharomyces rouxii as influenced by the procedure for sterilizing recovery media (YM agar [YMA], wort agar, cornmeal agar, and oatmeal agar) were investigated. Media were supplemented with various concentrations of glucose, sucrose, glycerol, or sorbitol and sterilized by autoclaving (110 degrees C, 15 min) and by repeated treatment with steam (100 degrees C). An increase in sensitivity was observed when heat-injured cells were plated on glucose-supplemented YMA at an aw of 0.880 compared with aws of 0.933 and 0.998. Colonies which developed from unheated and heated cells on YMA at aws of 0.998 and 0.933 generally exceeded 0.5 mm in diameter within 3.5 to 4 days of incubation at 25 degrees C, whereas colonies formed on YMA at an aw of 0.880 typically did not exceed 0.5 mm in diameter until after 5.5 to 6.5 days of incubation. The number of colonies exceeding 0.5 mm in diameter which were formed by heat-injured cells on YMA at an aw of 0.880 was 2 to 3 logs less than the total number of colonies detected, i.e., on YMA at an aw of 0.933 and using no limits of exclusion based on colony diameter. A substantial portion of cells which survived heat treatment were sublethally injured as evidenced by increased sensitivity to a suboptimum aw (0.880). In no instance was recovery of Z. rouxii significantly affected by medium sterilization procedure when glucose or sorbitol was used as the aw-suppressing solute.(ABSTRACT TRUNCATED AT 250 WORDS)

Is there a Space for Post-Colonial Theory in the Socio-Psychological Research on Consequences of Colonial Past?

Science.gov (United States)

Leone, Giovanna

2018-04-26

The focus of my commentary is two-fold. First, I discuss what appeared to me as the central theoretical focus of the article; the possibility to create a space, if at all, for integrating post-colonial theory into the broader research field of social and psychological studies of the consequences of colonial past. Second, I intend to show why, in my opinion, the methodological choices of the authors and the criteria adopted for corpus construction allowed for data that, although too thin to establishing the state of knowledge in the field of study on consequences of colonial past, is nevertheless very informative and thoughts-provoking. My conclusions suggest that this study is an innovative attempt at describing and grasping the results of a search guided by two among the more consolidated electronic datasets currently available for English-speaking scholars. However, this study may not easily understand which can be the space to integrate post-colonial theory in the field of research on consequences of colonial past. To better reach this aim, it is perhaps necessary to build another kind of corpus, open to other languages (starting from French) and focused also on other scientific products, as books or proceedings of congress. In addition, disciplinary boundaries have to be even more explored, starting from interdisciplinary studies on education and historical culture. In spite of these limitations, I am convinced that this innovative study by Tomicic and Berardi tackles issues of relevance to any serious effort towards reflecting on long-term consequences of colonial violence and opens up to valuable new research questions and methods, to be taken into serious account and further explored in future works.

Proton therapy

International Nuclear Information System (INIS)

Smith, Alfred R

2006-01-01

Proton therapy has become a subject of considerable interest in the radiation oncology community and it is expected that there will be a substantial growth in proton treatment facilities during the next decade. I was asked to write a historical review of proton therapy based on my personal experiences, which have all occurred in the United States, so therefore I have a somewhat parochial point of view. Space requirements did not permit me to mention all of the existing proton therapy facilities or the names of all of those who have contributed to proton therapy. (review)

Proton-proton bremsstrahlung in a relativistic covariant model

NARCIS (Netherlands)

Martinus, Gerard Henk

1998-01-01

Proton-proton bremsstrahlung is one of the simplest processes involving the half off-shell NN interaction. Since protons are equally-charged particles with the same mass, electric-dipole radiation is suppressed and higher-order effects play an important role. Thus it is possible to get information

The Genesis of Public Relations in British Colonial Practice.

Science.gov (United States)

Smyth, Rosaleen

2001-01-01

Demonstrates how the British Colonial Office employed public relations strategies as they administered the British colony of Northern Rhodesia before, during, and after World War II. Demonstrates how civil servants in London and colonial officials implemented public relations policies, strategies, and tactics on an ad hoc basis, covering political…

Proton-Proton and Proton-Antiproton Colliders

CERN Document Server

Scandale, Walter

2014-01-01

In the last five decades, proton–proton and proton–antiproton colliders have been the most powerful tools for high energy physics investigations. They have also deeply catalyzed innovation in accelerator physics and technology. Among the large number of proposed colliders, only four have really succeeded in becoming operational: the ISR, the SppbarS, the Tevatron and the LHC. Another hadron collider, RHIC, originally conceived for ion–ion collisions, has also been operated part-time with polarized protons. Although a vast literature documenting them is available, this paper is intended to provide a quick synthesis of their main features and key performance.

Sequential transition of the injury phenotype, temperature-dependent survival and transcriptional response in Listeria monocytogenes following lethal H2O2 exposure.

Science.gov (United States)

Ochiai, Yoshitsugu; Yamada, Fumiya; Yoshikawa, Yuko; Mochizuki, Mariko; Takano, Takashi; Hondo, Ryo; Ueda, Fukiko

2017-10-16

The food-borne pathogen Listeria monocytogenes is present persistently in food processing environments, where this bacterium is exposed to various stress factors, including oxidative stress. This study aimed to elucidate the temperature-dependent response of L. monocytogenes to H 2 O 2 exposure and the phenotypic changes in colony formation by H 2 O 2 -treated bacteria. Survival curves indicated an increase in the resistance to H 2 O 2 in L. monocytogenes as the temperature decreased during the stress exposure procedure. Transcriptional induction of genes with key roles in response to H 2 O 2 , including sigB and kat, was observed at 37°C, but not at 20°C, whereas other stress response genes were induced at both temperatures. Following H 2 O 2 exposure, L. monocytogenes produced small colony phenotypes and the colony size decreased in a stress exposure duration-dependent manner. Resuscitated cells with no ability to form colonies in the absence of sodium pyruvate were also found. Our findings show the possibility that a sequential transition in the injury phenotype from small colony phenotype to resuscitated cells occurred during the course of exposure to H 2 O 2 . The higher H 2 O 2 resistance at 20°C than 37°C suggests further investigation of the response to H 2 O 2 exposure under the lower temperatures, including refrigeration temperature, which may contribute to elucidation of bacterial survival over extended time periods in food-processing environments. Copyright © 2017 Elsevier B.V. All rights reserved.

Policing native pleasures: a colonial history.

Science.gov (United States)

Jabbar, Naheem

2012-12-01

The moral modality of colonial power is still with us when it comes to the recreation of sexual norms of traditional or feudal society. We can examine the emergent properties of colonial knowledge anew by exploring how the colonial regime's strategic attention of regulating brothels in India differed from the analytic of power Foucault described for sexuality in European society. It turns out that amongst other things, public anxieties about the failure of adaptation by South Asians are incapable of leaving sexuality aside as a key interpretive device for their culture. The British preoccupation with reproducing the dynamics of the bourgeois matrimonial market on foreign soil in the mid-nineteenth century similarly necessitated a sociological pretext for racial purity. However, the kind of knowledge a typical traveller and employee of the East India Company brought to the Victorian public from his own researches in the brothels and streets of colonial India, which revealed how popular prostitution was as a vice amongst the officer class, was also more than a welcome imaginary relief from Christian morality; it was an alternative vision of modernity. © London School of Economics and Political Science 2012.

Buckling instability in ordered bacterial colonies

Science.gov (United States)

Boyer, Denis; Mather, William; Mondragón-Palomino, Octavio; Orozco-Fuentes, Sirio; Danino, Tal; Hasty, Jeff; Tsimring, Lev S.

2011-04-01

Bacterial colonies often exhibit complex spatio-temporal organization. This collective behavior is affected by a multitude of factors ranging from the properties of individual cells (shape, motility, membrane structure) to chemotaxis and other means of cell-cell communication. One of the important but often overlooked mechanisms of spatio-temporal organization is direct mechanical contact among cells in dense colonies such as biofilms. While in natural habitats all these different mechanisms and factors act in concert, one can use laboratory cell cultures to study certain mechanisms in isolation. Recent work demonstrated that growth and ensuing expansion flow of rod-like bacteria Escherichia coli in confined environments leads to orientation of cells along the flow direction and thus to ordering of cells. However, the cell orientational ordering remained imperfect. In this paper we study one mechanism responsible for the persistence of disorder in growing cell populations. We demonstrate experimentally that a growing colony of nematically ordered cells is prone to the buckling instability. Our theoretical analysis and discrete-element simulations suggest that the nature of this instability is related to the anisotropy of the stress tensor in the ordered cell colony.

Buckling instability in ordered bacterial colonies

International Nuclear Information System (INIS)

Boyer, Denis; Mather, William; Mondragón-Palomino, Octavio; Danino, Tal; Hasty, Jeff; Orozco-Fuentes, Sirio; Tsimring, Lev S

2011-01-01

Bacterial colonies often exhibit complex spatio-temporal organization. This collective behavior is affected by a multitude of factors ranging from the properties of individual cells (shape, motility, membrane structure) to chemotaxis and other means of cell–cell communication. One of the important but often overlooked mechanisms of spatio-temporal organization is direct mechanical contact among cells in dense colonies such as biofilms. While in natural habitats all these different mechanisms and factors act in concert, one can use laboratory cell cultures to study certain mechanisms in isolation. Recent work demonstrated that growth and ensuing expansion flow of rod-like bacteria Escherichia coli in confined environments leads to orientation of cells along the flow direction and thus to ordering of cells. However, the cell orientational ordering remained imperfect. In this paper we study one mechanism responsible for the persistence of disorder in growing cell populations. We demonstrate experimentally that a growing colony of nematically ordered cells is prone to the buckling instability. Our theoretical analysis and discrete-element simulations suggest that the nature of this instability is related to the anisotropy of the stress tensor in the ordered cell colony

Mem and Cookie: The Colonial Kitchen in Malaysia and Singapore

Directory of Open Access Journals (Sweden)

Cecilia Leong-Salobir

2015-09-01

Full Text Available This paper examines the emergence of a distinctive colonial cuisine in the British colonies of Malaysia and Singapore beginning in the late nineteenth century. This colonial cuisine evolved over time and was a combination of culinary practices derived from European and Asian foodways, much of which came from colonial India. As in India, this acculturation developed through the reliance of colonizers on their domestic servants for food preparation. While domestic servants (as cooks, or known locally as “cookie” were generally represented as dirty, dishonest and lacking in intelligence according to colonial narratives, they were responsible for the preparation of food for the family. Asian cooks in the colonial home played a much more crucial role than the negative image painted of them by British colonizers and other historians. While the mem (short for memsahib, meaning mistress held the supervisory role of the household, it was the physical contribution of the domestic servants that enabled her to fulfill this function. The large number of servants employed enabled the mem to make the colonial home move seamlessly between the private domain of the home and the official venue for the empire’s tasks. The mem as the head of the household decided on the rituals and tasks that defined the colonial space as home, and as a bastion of white imperialism. In contrast, it was the cooks’ local knowledge that procured food. Most kitchens were fashioned according to the requirements of the servants and the cooks did all the cooking, usually preparing local dishes. The argument is that, had it not been for the servants’ input, the mems would have had to work harder. As it was, the work of the servants not only saved white labour, it helped shape colonial culture, despite the Britons’ best efforts to keep themselves socially distant. Colonial cuisine would not have developed with such distinctive features without the skills and local knowledge of

Dynamics of Anti-Proton -- Protons and Anti-Proton -- Nucleus Reactions

CERN Document Server

Galoyan, A; Uzhinsky, V

2016-01-01

A short review of simulation results of anti-proton-proton and anti-proton-nucleus interactions within the framework of Geant4 FTF (Fritiof) model is presented. The model uses the main assumptions of the Quark-Gluon-String Model or Dual Parton Model. The model assumes production and fragmentation of quark-anti-quark and diquark-anti-diquark strings in the mentioned interactions. Key ingredients of the model are cross sections of string creation processes and an usage of the LUND string fragmentation algorithm. They allow one to satisfactory describe a large set of experimental data, especially, a strange particle production, Lambda hyperons and K mesons.

Juvenile survival in a tropical population of roseate terns: Interannual variation and effect of tick parasitism

Science.gov (United States)

Monticelli, David; Ramos, Jaime A.; Hines, James E.; Nichols, James D.; Spendelow, Jeffrey A.

2008-01-01

Many demographic studies on long-lived seabirds have focused on the estimation of adult survival, but much less is known about survival during the early years of life, especially in tropical species. We report analyses of a capture–recapture dataset of 685 roseate terns ringed as fledglings and adults between 1998 and 2005 on Aride Island, Seychelles, and recaptured/resighted at the same colony site over a 5 yr (2002 to 2006) period. A multistate model was used to estimate survival for different age classes, including juvenile (first-year) birds returning as non-breeding prospectors. The effect of infestation by parasites (ticks) on survival was also examined. Overall, the estimated return of first-year individuals to the natal colony was very variable, ranging from 2 to 22%. Conditioned on survival, the probability of returning from Age 2 yr onwards increased to 70%. Survival rates were best modeled as time-specific, with estimates varying from 0.02 to 1.00 (mean 0.69) in first-year birds with a marked negative effect of tick infestation. In older birds (minimum age of 2 yr), the annual estimates fell between 0.69 and 0.86 (mean 0.77). Using a components of variance approach for estimation of year-to-year variation, we found high temporal variability for first-year individuals (coefficient of variation [CV] = 65%) compared to much less variation in the survival rate of older birds (CV = 9%). These findings agree with the life-history prediction that demographic rates of juveniles are usually lower and more variable than those of older individuals. Our results are also consistent with the predicted negative effect of tick parasitism on juvenile survival. Compared with data from other roseate tern populations, survival over the first 2 yr (Age 0 to 2 yr) was 18 to 40% higher in this study, suggesting that a high ‘young’ survival rate may be an important demographic trait in this tropical population to compensate for the low annual reproductive success. Our

The psychology of colonialism: sex, age, and ideology in British India.

Science.gov (United States)

Nandy, A

1982-08-01

It is becoming more and more obvious that colonialism--as we have come to know it during the last two hundred years--cannot be identified with only economic gain and political power. In Manchuria, Japan consistently lost money, and for many years colonial Indochina, Algeria and Angola, instead of increasing the political power of France and Portugal, sapped it. This did not make Manchuria, Indochina, Algeria or Angola less important as colonies. Nor did it disprove the point that economic gain and political power are important motives in a colonial situation. It only showed that colonialism could be characterized by the search for economic and political advantage without concomitant real economic or political gains, and sometimes even with economic or political losses. This essay argues that the first differentia of colonialism is a state of mind in the colonizers and the colonized, a colonial consciousness which includes the sometimes unrealizable wish to make economic and political profits from the colonies, but other elements, too. The political economy of colonization is of course important, but the vulgarity and insanity of colonialism are principally expressed in the sphere of psychology. The following pages will explore some of these psychological contours of colonialism in the rulers and the ruled and try to define colonialism as a shared culture which may not always begin with the establishment of alien rule in a society and end with the departure of the alien rulers from the colony. The example I shall use will be that of India, where a colonial political economy began to operate seventy-five years before the full-blown ideology of British imperialism became dominant, and where thirty years after the formal ending of the raj, the ideology of colonialism is still triumphant in many sectors of life.

Synthetic quorum sensing in model microcapsule colonies

Science.gov (United States)

Shum, Henry; Balazs, Anna C.

2017-08-01

Biological quorum sensing refers to the ability of cells to gauge their population density and collectively initiate a new behavior once a critical density is reached. Designing synthetic materials systems that exhibit quorum sensing-like behavior could enable the fabrication of devices with both self-recognition and self-regulating functionality. Herein, we develop models for a colony of synthetic microcapsules that communicate by producing and releasing signaling molecules. Production of the chemicals is regulated by a biomimetic negative feedback loop, the “repressilator” network. Through theory and simulation, we show that the chemical behavior of such capsules is sensitive to both the density and number of capsules in the colony. For example, decreasing the spacing between a fixed number of capsules can trigger a transition in chemical activity from the steady, repressed state to large-amplitude oscillations in chemical production. Alternatively, for a fixed density, an increase in the number of capsules in the colony can also promote a transition into the oscillatory state. This configuration-dependent behavior of the capsule colony exemplifies quorum-sensing behavior. Using our theoretical model, we predict the transitions from the steady state to oscillatory behavior as a function of the colony size and capsule density.

Theoretical Analysis of Proton Relays in Electrochemical Proton-Coupled Electron Transfer

International Nuclear Information System (INIS)

Auer, Benjamin; Fernandez, Laura; Hammes-Schiffer, Sharon

2011-01-01

The coupling of long-range electron transfer to proton transport over multiple sites plays a vital role in many biological and chemical processes. Recently a molecule with a hydrogen-bond relay inserted between the proton donor and acceptor sites in a proton-coupled electron transfer (PCET) system was studied electrochemically. The standard rate constants and kinetic isotope effects (KIEs) were measured experimentally for this system and a related single proton transfer system. In the present paper, these systems are studied theoretically using vibronically nonadiabatic rate constant expressions for electrochemical PCET. Application of this approach to proton relays requires the calculation of multidimensional proton vibrational wavefunctions and incorporation of multiple proton donor-acceptor motions. The calculated KIEs and relative standard rate constants for the single and double proton transfer systems are in agreement with the experimental data. The calculations indicate that the standard rate constant is lower for the double proton transfer system because of the smaller overlap integral between the ground state reduced and oxidized proton vibrational wavefunctions for this system, resulting in greater contributions from excited electron-proton vibronic states with higher free energy barriers. The decrease in proton donor-acceptor distances due to thermal fluctuations and the contributions from excited electron-proton vibronic states play important roles in proton relay systems. The theory suggests that the PCET rate constant may be increased by decreasing the equilibrium proton donor-acceptor distances or modifying the thermal motions of the molecule to facilitate the concurrent decrease of these distances. The submission of this journal article in ERIA is a requirement of the EFRC subcontract with Pennsylvania State University collaborators to get publications to OSTI.

Inactivation of HTB63 human melanoma cells by irradiation with protons and gamma rays.

Science.gov (United States)

Ristic-Fira, Aleksandra; Petrovic, Ivan; Todorovic, Danijela; Koricanac, Lela; Vujèic, Miroslava; Demajo, Miroslav; Sabini, Gabriella; Cirrone, Pablo; Cuttone, Giacomo

2004-12-01

The effects of single irradiation with gamma rays and protons on HTB63 human melanoma cell growth were compared. The exponentially growing cells were irradiated with gamma rays or protons using doses ranging from 2-20 Gy. At 48 h of post-irradiation incubation under standard conditions, cell survival and induction of apoptotic cell death were examined. The best effect of the single irradiation with gamma rays was the reduction of cell growth by up to 26% (p=0.048, irradiation vs. control), obtained using the dose of 16 Gy. The same doses of proton irradiation, having energy at the target of 22.6 MeV, significantly inhibited melanoma cell growth. Doses of 12 and 16 Gy of protons provoked growth inhibition of 48.9% (p=0.003, irradiation vs. control) and 51.2% (p=0.012, irradiation vs. control) respectively. Irradiation with 12 and 16 Gy protons, compared to the effects of the same doses of gamma rays, significantly reduced melanoma cell growth (p=0.015 and p=0.028, protons vs. gamma rays, respectively). Estimated RBEs for growth inhibition of HTB63 cells ranged from 1.02 to 1.45. The electrophoretical analyses of DNA samples and flow cytometric evaluation have shown a low percentage of apoptotic cells after both types of irradiation. The better inhibitory effect achieved by protons in contrast to gamma rays, can be explained considering specific physical properties of protons, especially taking into account the highly localized energy deposition (high LET).

Collaboration, Coproduction, and Code-Switching: Colonial Cinema and Postcolonial Archaeology

Directory of Open Access Journals (Sweden)

Nayoung Aimee Kwon

2012-12-01

Full Text Available This article reassesses the issue of colonial collaboration in the Japanese empire by examining the rise of cinematic coproductions between Japanese and Korean filmmakers. By the late 1930s, colonial Korea’s filmmaking industry had been fully subsumed into the Japanese film industry, and regulations were established that required all films to assimilate imperial policies. The colonial government’s active promotion of colonial “collaboration” and “coproduction” between the colonizers and the colonized ideologically worked to obfuscate these increasing restrictions in colonial film productions while producing complex and contentious desires across the colonial divide. The very concepts of “collaboration” and “coproduction” need to be redefined in light of increasingly complex imperial hierarchies and entanglements. Taking the concept of “code-switching” beyond its linguistic origins, this article argues that we must reassess texts of colonial collaboration and coproduction produced at a time when Korean film had to “code-switch” into Japanese—to linguistically, culturally, and politically align itself with the wartime empire. The article argues that recently excavated films from colonial and Cold War archives, such as Spring in the Korean Peninsula, offer a rare glimpse into repressed and contested histories and raise the broader conundrum of accessing and assessing uneasily commingled colonial pasts of Asian-Pacific nations in the ruins of postcolonial aftermath.

Lung Cancer Cell Line Screen Links Fanconi Anemia/BRCA Pathway Defects to Increased Relative Biological Effectiveness of Proton Radiation

International Nuclear Information System (INIS)

Liu, Qi; Ghosh, Priyanjali; Magpayo, Nicole; Testa, Mauro; Tang, Shikui; Gheorghiu, Liliana; Biggs, Peter; Paganetti, Harald; Efstathiou, Jason A.; Lu, Hsiao-Ming; Held, Kathryn D.; Willers, Henning

2015-01-01

Purpose: Growing knowledge of genomic heterogeneity in cancer, especially when it results in altered DNA damage responses, requires re-examination of the generic relative biological effectiveness (RBE) of 1.1 of protons. Methods and Materials: For determination of cellular radiosensitivity, we irradiated 17 lung cancer cell lines at the mid-spread-out Bragg peak of a clinical proton beam (linear energy transfer, 2.5 keV/μm). For comparison, 250-kVp X rays and 137 Cs γ-rays were used. To estimate the RBE of protons relative to 60 Co (Co60eq), we assigned an RBE(Co60Eq) of 1.1 to X rays to correct the physical dose measured. Standard DNA repair foci assays were used to monitor damage responses. FANCD2 was depleted using RNA interference. Results: Five lung cancer cell lines (29.4%) exhibited reduced clonogenic survival after proton irradiation compared with X-irradiation with the same physical doses. This was confirmed in a 3-dimensional sphere assay. Corresponding proton RBE(Co60Eq) estimates were statistically significantly different from 1.1 (P≤.05): 1.31 to 1.77 (for a survival fraction of 0.5). In 3 of these lines, increased RBE was correlated with alterations in the Fanconi anemia (FA)/BRCA pathway of DNA repair. In Calu-6 cells, the data pointed toward an FA pathway defect, leading to a previously unreported persistence of proton-induced RAD51 foci. The FA/BRCA-defective cells displayed a 25% increase in the size of subnuclear 53BP1 foci 18 hours after proton irradiation. Conclusions: Our cell line screen has revealed variations in proton RBE that are partly due to FA/BRCA pathway defects, suggesting that the use of a generic RBE for cancers should be revisited. We propose that functional biomarkers, such as size of residual 53BP1 foci, may be used to identify cancers with increased sensitivity to proton radiation

Lung Cancer Cell Line Screen Links Fanconi Anemia/BRCA Pathway Defects to Increased Relative Biological Effectiveness of Proton Radiation

Energy Technology Data Exchange (ETDEWEB)

Liu, Qi; Ghosh, Priyanjali; Magpayo, Nicole [Laboratory of Cellular and Molecular Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Testa, Mauro; Tang, Shikui [Division of Radiation Physics, Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Gheorghiu, Liliana [Laboratory of Cellular and Molecular Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Biggs, Peter; Paganetti, Harald [Division of Radiation Physics, Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Efstathiou, Jason A. [Laboratory of Cellular and Molecular Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Lu, Hsiao-Ming [Division of Radiation Physics, Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Held, Kathryn D. [Laboratory of Cellular and Molecular Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Willers, Henning, E-mail: hwillers@mgh.harvard.edu [Laboratory of Cellular and Molecular Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States)

2015-04-01

Purpose: Growing knowledge of genomic heterogeneity in cancer, especially when it results in altered DNA damage responses, requires re-examination of the generic relative biological effectiveness (RBE) of 1.1 of protons. Methods and Materials: For determination of cellular radiosensitivity, we irradiated 17 lung cancer cell lines at the mid-spread-out Bragg peak of a clinical proton beam (linear energy transfer, 2.5 keV/μm). For comparison, 250-kVp X rays and {sup 137}Cs γ-rays were used. To estimate the RBE of protons relative to {sup 60}Co (Co60eq), we assigned an RBE(Co60Eq) of 1.1 to X rays to correct the physical dose measured. Standard DNA repair foci assays were used to monitor damage responses. FANCD2 was depleted using RNA interference. Results: Five lung cancer cell lines (29.4%) exhibited reduced clonogenic survival after proton irradiation compared with X-irradiation with the same physical doses. This was confirmed in a 3-dimensional sphere assay. Corresponding proton RBE(Co60Eq) estimates were statistically significantly different from 1.1 (P≤.05): 1.31 to 1.77 (for a survival fraction of 0.5). In 3 of these lines, increased RBE was correlated with alterations in the Fanconi anemia (FA)/BRCA pathway of DNA repair. In Calu-6 cells, the data pointed toward an FA pathway defect, leading to a previously unreported persistence of proton-induced RAD51 foci. The FA/BRCA-defective cells displayed a 25% increase in the size of subnuclear 53BP1 foci 18 hours after proton irradiation. Conclusions: Our cell line screen has revealed variations in proton RBE that are partly due to FA/BRCA pathway defects, suggesting that the use of a generic RBE for cancers should be revisited. We propose that functional biomarkers, such as size of residual 53BP1 foci, may be used to identify cancers with increased sensitivity to proton radiation.

For the youth : juvenile delinquency, colonial civil society and the late colonial state in the Netherlands Indies, 1872-1942

NARCIS (Netherlands)

Dirks, Annelieke

2011-01-01

This dissertation project focuses on forced re-education policies for juvenile delinquents in the Netherlands Indies (now Indonesia) and uses this topic to show the interaction between a 'modernizing' Dutch colonial state and the growth of a colonial civil society, between approximately 1872 and

Genetic variation at the MHC DRB1 locus is similar across Gunnison's prairie dog (Cynomys gunnisoni) colonies regardless of plague history

Science.gov (United States)

Cobble, Kacy R.; Califf, Katy J.; Stone, Nathan E.; Shuey, Megan M.; Birdsell, Dawn; Colman, Rebecca E.; Schupp, James M.; Aziz, Maliha; Van Andel, Roger; Rocke, Tonie E.; Wagner, David M.; Busch, Joseph D.

2016-01-01

Yersinia pestis was introduced to North America around 1900 and leads to nearly 100% mortality in prairie dog (Cynomys spp.) colonies during epizootic events, which suggests this pathogen may exert a strong selective force. We characterized genetic diversity at an MHC class II locus (DRB1) in Gunnison's prairie dog (C. gunnisoni) and quantified population genetic structure at the DRB1versus 12 microsatellite loci in three large Arizona colonies. Two colonies, Seligman (SE) and Espee Ranch (ES), have experienced multiple plague-related die-offs in recent years, whereas plague has never been documented at Aubrey Valley (AV). We found fairly low allelic diversity at the DRB1 locus, with one allele (DRB1*01) at high frequency (0.67–0.87) in all colonies. Two otherDRB1 alleles appear to be trans-species polymorphisms shared with the black-tailed prairie dog (C. ludovicianus), indicating that these alleles have been maintained across evolutionary time frames. Estimates of genetic differentiation were generally lower at the MHC locus (FST = 0.033) than at microsatellite markers (FST = 0.098). The reduced differentiation at DRB1 may indicate that selection has been important for shaping variation at MHC loci, regardless of the presence or absence of plague in recent decades. However, genetic drift has probably also influenced theDRB1 locus because its level of differentiation was not different from that of microsatellites in anFST outlier analysis. We then compared specific MHC alleles to plague survivorship in 60C. gunnisoni that had been experimentally infected with Y. pestis. We found that survival was greater in individuals that carried at least one copy of the most common allele (DRB1*01) compared to those that did not (60% vs. 20%). Although the sample sizes of these two groups were unbalanced, this result suggests the possibility that this MHC class II locus, or a nearby linked gene, could play a role in plague survival.

Proton: the particle.

Science.gov (United States)

Suit, Herman

2013-11-01

The purpose of this article is to review briefly the nature of protons: creation at the Big Bang, abundance, physical characteristics, internal components, and life span. Several particle discoveries by proton as the experimental tool are considered. Protons play important roles in science, medicine, and industry. This article was prompted by my experience in the curative treatment of cancer patients by protons and my interest in the nature of protons as particles. The latter has been stimulated by many discussions with particle physicists and reading related books and journals. Protons in our universe number ≈10(80). Protons were created at 10(-6) -1 second after the Big Bang at ≈1.37 × 10(10) years beforethe present. Proton life span has been experimentally determined to be ≥10(34) years; that is, the age of the universe is 10(-24)th of the minimum life span of a proton. The abundance of the elements is hydrogen, ≈74%; helium, ≈24%; and heavier atoms, ≈2%. Accordingly, protons are the dominant baryonic subatomic particle in the universe because ≈87% are protons. They are in each atom in our universe and thus involved in virtually every activity of matter in the visible universe, including life on our planet. Protons were discovered in 1919. In 1968, they were determined to be composed of even smaller particles, principally quarks and gluons. Protons have been the experimental tool in the discoveries of quarks (charm, bottom, and top), bosons (W(+), W(-), Z(0), and Higgs), antiprotons, and antineutrons. Industrial applications of protons are numerous and important. Additionally, protons are well appreciated in medicine for their role in radiation oncology and in magnetic resonance imaging. Protons are the dominant baryonic subatomic particle in the visible universe, comprising ≈87% of the particle mass. They are present in each atom of our universe and thus a participant in every activity involving matter. Copyright © 2013 Elsevier Inc. All

Proton: The Particle

Energy Technology Data Exchange (ETDEWEB)

Suit, Herman

2013-11-01

The purpose of this article is to review briefly the nature of protons: creation at the Big Bang, abundance, physical characteristics, internal components, and life span. Several particle discoveries by proton as the experimental tool are considered. Protons play important roles in science, medicine, and industry. This article was prompted by my experience in the curative treatment of cancer patients by protons and my interest in the nature of protons as particles. The latter has been stimulated by many discussions with particle physicists and reading related books and journals. Protons in our universe number ≈10{sup 80}. Protons were created at 10{sup −6} –1 second after the Big Bang at ≈1.37 × 10{sup 10} years beforethe present. Proton life span has been experimentally determined to be ≥10{sup 34} years; that is, the age of the universe is 10{sup −24}th of the minimum life span of a proton. The abundance of the elements is hydrogen, ≈74%; helium, ≈24%; and heavier atoms, ≈2%. Accordingly, protons are the dominant baryonic subatomic particle in the universe because ≈87% are protons. They are in each atom in our universe and thus involved in virtually every activity of matter in the visible universe, including life on our planet. Protons were discovered in 1919. In 1968, they were determined to be composed of even smaller particles, principally quarks and gluons. Protons have been the experimental tool in the discoveries of quarks (charm, bottom, and top), bosons (W{sup +}, W{sup −}, Z{sup 0}, and Higgs), antiprotons, and antineutrons. Industrial applications of protons are numerous and important. Additionally, protons are well appreciated in medicine for their role in radiation oncology and in magnetic resonance imaging. Protons are the dominant baryonic subatomic particle in the visible universe, comprising ≈87% of the particle mass. They are present in each atom of our universe and thus a participant in every activity involving matter.

Conservation of colonial built heritage: practical considerations and cultural constraints in Rio de Janeiro

Science.gov (United States)

Smith, B.; Neto, J.; Silva, M.; Warke, P.; Curran, J.

2003-04-01

As the 500th anniversary of European arrival in Brazil approached in the year 2000, it provided a stimulus for the country to review the cultural and economic significance of its remaining colonial built heritage. This is not least because of the growing awareness that built heritage is an important attractor for high income tourism and an increasing willingness amongst the population at large to accept colonial artefacts as a legitimate component of national history. Nowhere is this revision more apposite than in the adjacent cities of Rio de Janeiro and Niteroi. In both cities much of the colonial heritage was swept away during the late twentieth century in a tide of reconstruction that was symbolic of self-proclaimed Brazilian modernity and that signified for many a break with their colonial past. Those elements of colonial heritage that have survived have done so largely because of their ownership either by the church or the military. However, whilst this has often protected the overall building, the detailed fabric of such structures has at best been neglected and in many cases abused. As a consequence, stonework, in particular, can exhibit a range of decay features that must be addressed if this heritage is to be preserved and its educational and economic potential realised. In this presentation, we review changing attitudes towards conservation as illustrated by a number of key structures, including the large stone forts that guard the entrance to Guanabara Bay. This is combined with a detailed examination of threats to the integrity of their stonework consequent on prolonged exposure in a humid tropical maritime environment. Most of these structures are built of local, very durable augen gneiss. However, studies of natural rock outcrops show that this rock does weather, and that breakdown can be episodic as localised strength thresholds are breached. Surveys suggest that some buildings may be approaching such threshold conditions, whereby stresses

Proton detection in the neutron lifetime experiment PENeLOPE

Energy Technology Data Exchange (ETDEWEB)

Tietze, Christian [Technische Universitaet Muenchen, Physik Department E18 (Germany); Collaboration: PENeLOPE-Collaboration

2015-07-01

Although neutron lifetime plays an important role in the Standard Model of particle physics, τ{sub n} is not very precisely know and often discussed. The official PDG mean value has been lowered during the last years by more than 6σ to the new value of 880.3 ± 1.1 s. The new precision experiment PENeLOPE, which is currently developed at Technische Universitaet Muenchen, will help to clear this up. Ultra-cold neutrons are lossless stored in a magneto-gravitational trap, formed by superconducting coils. The combined determination of τ{sub n} by counting the surviving neutrons after each storage cycle on one side and in-situ detection of the decay protons on the other side together with a very good handle on systematic errors leads to an unprecedented precision of the neutron lifetime value of 0.1s. This contribution will give an overview of the challenges concerning proton detection under the exceptional requirements of this experiment. The developed concept of using avalanche photodiodes for direct proton detection will be presented as well as results from first measurements with a prototype detector read out by particular developed electronics.

Transverse Imaging of the Proton in Exclusive Diffractive pp Scattering

International Nuclear Information System (INIS)

Christian Weiss; Leonid Frankfurt; Charles Hyde-Wright; Mark Strikman

2006-01-01

In a forthcoming paper we describe a new approach to rapidity gap survival (RGS) in the production of high-mass systems (H = dijet, Higgs, etc.) in exclusive double-gap diffractive pp scattering, pp -> p + H + p. It is based on the idea that hard and soft interactions are approximately independent (QCD factorization), and allows us to calculate the RGS probability in a model-independent way in terms of the gluon generalized parton distributions (GPDs) in the colliding protons and the pp elastic scattering amplitude. Here we focus on the transverse momentum dependence of the cross section. By measuring the ''diffraction pattern'', one can perform detailed tests of the interplay of hard and soft interactions, and even extract information about the gluon GPD in the proton from the data

Morphological Diversity of the Colony Produced by Bacteria Proteus mirabilis

Science.gov (United States)

Nakahara, Akio; Shimada, Yuji; Wakita, Jun-ichi; Matsushita, Mitsugu; Matsuyama, Tohey

1996-08-01

Morphological changes of colonies have been investigatedfor a bacterial strain of Proteus mirabilis, which is a famous speciesfor producing concentric-ring-like colonies. It was found that colony patterns can be classified into three types,i.e., cyclic spreading, diffusion-limited growth (DLA-like)and three-dimensional growth (inside the agar medium) patterns. Cyclic spreading patterns can further be classifiedinto three subgroups, i.e., concentric-ring, homogeneous and spatiotemporal patterns. These subgroups were classified by examining the development of colony structure after colonies spread all over petri-dishes. Comparison of the results with thoseof another bacterial species Bacillus subtilis is also discussed.

Colonialism as a Broader Social Determinant of Health

Directory of Open Access Journals (Sweden)

Karina Czyzewski

2011-05-01

Full Text Available A proposed broader or Indigenized social determinants of health framework includes "colonialism" along with other global processes. What does it mean to understand Canadian colonialism as a distal determinant of Indigenous health? This paper reviews pertinent discourses surrounding Indigenous mental health in Canada.With an emphasis on the notion of intergenerational trauma, there are real health effects of social, political, and economic marginalization embodied within individuals, which can collectively affect entire communities. Colonialism can also be enacted and reinforced within Indigenous mental health discourse, thus influencing scholarly and popular perceptions. Addressing this distal determinant through policy work necessitates that improving Indigenous health is inherently related to improving these relationships, i.e. eliminating colonial relations, and increasing self-determination.

The practical Pomeron for high energy proton collimation

Energy Technology Data Exchange (ETDEWEB)

Appleby, R.B. [University of Manchester, The Cockcroft Institute, Manchester (United Kingdom); Barlow, R.J.; Toader, A. [The University of Huddersfield, Huddersfield (United Kingdom); Molson, J.G. [Univ. Paris-Sud, CNRS/IN2P3, Universite Paris-Saclay, LAL, Orsay (France); Serluca, M. [CERN, Geneva (Switzerland)

2016-10-15

We present a model which describes proton scattering data from ISR to Tevatron energies, and which can be applied to collimation in high energy accelerators, such as the LHC and FCC. Collimators remove beam halo particles, so that they do not impinge on vulnerable regions of the machine, such as the superconducting magnets and the experimental areas. In simulating the effect of the collimator jaws it is crucial to model the scattering of protons at small momentum transfer t, as these protons can subsequently survive several turns of the ring before being lost. At high energies these soft processes are well described by Pomeron exchange models. We study the behaviour of elastic and single-diffractive dissociation cross sections over a wide range of energy, and show that the model can be used as a global description of the wide variety of high energy elastic and diffractive data presently available. In particular it models low mass diffraction dissociation, where a rich resonance structure is present, and thus predicts the differential and integrated cross sections in the kinematical range appropriate to the LHC. We incorporate the physics of this model into the beam tracking code MERLIN and use it to simulate the resulting loss maps of the beam halo lost in the collimators in the LHC. (orig.)

The practical Pomeron for high energy proton collimation

Science.gov (United States)

Appleby, R. B.; Barlow, R. J.; Molson, J. G.; Serluca, M.; Toader, A.

2016-10-01

We present a model which describes proton scattering data from ISR to Tevatron energies, and which can be applied to collimation in high energy accelerators, such as the LHC and FCC. Collimators remove beam halo particles, so that they do not impinge on vulnerable regions of the machine, such as the superconducting magnets and the experimental areas. In simulating the effect of the collimator jaws it is crucial to model the scattering of protons at small momentum transfer t, as these protons can subsequently survive several turns of the ring before being lost. At high energies these soft processes are well described by Pomeron exchange models. We study the behaviour of elastic and single-diffractive dissociation cross sections over a wide range of energy, and show that the model can be used as a global description of the wide variety of high energy elastic and diffractive data presently available. In particular it models low mass diffraction dissociation, where a rich resonance structure is present, and thus predicts the differential and integrated cross sections in the kinematical range appropriate to the LHC. We incorporate the physics of this model into the beam tracking code MERLIN and use it to simulate the resulting loss maps of the beam halo lost in the collimators in the LHC.

Social interactions in the central nest of Coptotermes formosanus juvenile colonies

Science.gov (United States)

Juvenile colonies of Coptotermes formosanus Shiraki were investigated to determine the social interactions among all individuals near the central nest of a colony. The behavioral repertoire of whole colonies of subterranean termites has yet to be identified because of their cryptic nests. Colonies w...

In vitro radiosensitivity of human fresh T-lymphocytes by colony formation assay using PHA and recombinant Interleukin-2

International Nuclear Information System (INIS)

Tatsugawa, Kaori; Nakamura, Nori; Hakoda, Masayuki; Akiyama, Mitoshi.

1988-05-01

In vitro culture conditions for colony formation of human fresh peripheral T-cells using phytohemagglutinin (PHA) and recombinant Interleukin-2 are defined. Peripheral lymphocytes, from six individuals, were exposed to X or gamma rays in vitro, and dose-survival curves were obtained. The results showed typical sigmoid curves similar to those observed when other mammalian cells are exposed to radiation. The D 10 (dose required to kill 90 % of the cells) was found to be 3.0 to 3.5 Gy. (author)

Preliminary results of proton therapy in choroidal melanoma at the centre de proton therapy d`Orsay (C.P.O.): 464 initial cases; Resultats preliminaires de la protontherapie du melanome de la choroide au centre de protontherapie d`Orsay (CPO): les 464 premiers cas

Energy Technology Data Exchange (ETDEWEB)

Desjardins, L.; Levy, C.; D`hermies, F.; Frau, E.; Schlienger, P.; Habrand, J.L.; Mammar, H.; Schwartz, L.; Mazal, A.; Delacroix, S.; Nauraye, C.; Ferrand, R.; Asselain, B. [Centre de protontherapie d`Orsay, 91 - Orsay (France)

1997-06-01

Retrospective analysis of the treatment of choroidal melanoma with proton-therapy at the Centre de protontherapie d`Orsay, France. Between September 1991 and September 1995, 612 patients presenting with choroidal melanoma were treated by proton-therapy in Orsay. Following initial management of the first 464 patients, results were analyzed, as were results after a 1-year follow up for 305 patients, a 2-year follow-up for 169 patients, and a 3-year follow-up for 59 patients. Univariate analysis showed that the actuarial local recurrence rate was 5 %, the 3-year survival rate 88 %, and the overall metastatic rate 5%. The initial tumor volume was the most significant predictive factor for visual results and metastases. Multivariate analysis revealed that visual results were significantly related to the initial tumor volume, initial retinal detachment, and total dose delivered to the optic nerve and macula. Proton-therapy of choroidal melanoma allows in most cases conservation of the eye without modification of survival. Visual results mainly depend on the site and size of the tumor. (author) 16 refs.

Honey Bee Antiviral Immune Barriers as Affected by Multiple Stress Factors: A Novel Paradigm to Interpret Colony Health Decline and Collapse

Directory of Open Access Journals (Sweden)

Francesco Nazzi

2018-03-01

Full Text Available Any attempt to outline a logical framework in which to interpret the honey bee health decline and its contribution to elevated colony losses should recognize the importance of the multifactorial nature of the responsible syndrome and provide a functional model as a basis for defining and testing working hypotheses. We propose that covert infections by deformed wing virus (DWV represent a sword of Damocles permanently threatening the survival of honey bee colonies and suggest that any factor affecting the honey bee’s antiviral defenses can turn this pathogen into a killer. Here we discuss the available experimental evidence in the framework of a model based on honey bee immune competence as affected by multiple stress factors that is proposed as a conceptual tool for analyzing bee mortality and its underlying mechanisms.

Survival of heterotrophic bacteria in water environment under substrate deficiency

International Nuclear Information System (INIS)

Toth, D.

1989-01-01

The relationship between metabolic changes and survival of bacteria in the water environment under substrate deficiency was studied. The main factors supporting cell survival were cryptic growth, utilization of endogenous reserve substances and reorganization of metabolic activities. Based on the utilization of cell-free extract or lysates from dead bacteria, an Enterobacter aerogenes cell suspension yielded 50% more colonies. Metabolic processes of starved heterotrophic bacteria changed markedly and became stabilized at a lower level depending on species involved. The rate of utilization of endogenous reserve substances as indicated by endogenous respiration was related to the rate of cell mortality. Of the test bacteria, Pseudomonas fluorescens showed the lowest rates of endogenous respiration and mortality while in Enterobacter aerogenes these two rates were the highest. (author). 3 figs., 2 tabs.., 16 refs

Antiproton-proton and proton-proton elastic scattering at 100 and 200 GeV/c

International Nuclear Information System (INIS)

Kaplan, D.H.; Karchin, P.; Orear, J.; Kalbach, R.M.; Krueger, K.W.; Pifer, A.E.; Baker, W.F.; Eartly, D.P.; Klinger, J.S.; Lennox, A.J.; Rubinstein, R.; McHugh, S.F.

1982-01-01

Antiproton-proton elastic scattering has been measured at 100 GeV/c for 0.5 2 and at 200 GeV/c for 0.9 2 . The data show that the -tapprox. =1.4 (GeV/c) 2 dip recently observed at 50 GeV/c persists to higher incident momenta. Proton-proton measurements made at the same beam momenta show similar structure

Disruption of SLX4-MUS81 Function Increases the Relative Biological Effectiveness of Proton Radiation

Energy Technology Data Exchange (ETDEWEB)

Liu, Qi [Laboratory of Cellular and Molecular Radiation Oncology, Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Underwood, Tracy S.A.; Kung, Jong [Division of Radiation Physics, Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Wang, Meng [Laboratory of Cellular and Molecular Radiation Oncology, Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Lu, Hsiao-Ming; Paganetti, Harald [Division of Radiation Physics, Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Held, Kathryn D.; Hong, Theodore S.; Efstathiou, Jason A. [Laboratory of Cellular and Molecular Radiation Oncology, Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Willers, Henning, E-mail: hwillers@mgh.harvard.edu [Laboratory of Cellular and Molecular Radiation Oncology, Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States)

2016-05-01

Purpose: Clinical proton beam therapy has been based on the use of a generic relative biological effectiveness (RBE) of ∼1.1. However, emerging data have suggested that Fanconi anemia (FA) and homologous recombination pathway defects can lead to a variable RBE, at least in vitro. We investigated the role of SLX4 (FANCP), which acts as a docking platform for the assembly of multiple structure-specific endonucleases, in the response to proton irradiation. Methods and Materials: Isogenic cell pairs for the study of SLX4, XPF/ERCC1, MUS81, and SLX1 were irradiated at the mid-spread-out Bragg peak of a clinical proton beam (linear energy transfer 2.5 keV/μm) or with 250 kVp x-rays, and the clonogenic survival fractions were determined. To estimate the RBE of the protons relative to cobalt-60 photons (Co60Eq), we assigned a RBE(Co60Eq) of 1.1 to x-rays to correct the physical dose measured. Standard DNA repair foci assays were used to monitor the damage responses, and the cell cycle distributions were assessed by flow cytometry. The poly(ADP-ribose) polymerase inhibitor olaparib was used for comparison. Results: Loss of SLX4 function resulted in an enhanced proton RBE(Co60Eq) of 1.42 compared with 1.11 for wild-type cells (at a survival fraction of 0.1; P<.05), which correlated with increased persistent DNA double-strand breaks in cells in the S/G{sub 2} phase. Genetic analysis identified the SLX4-binding partner MUS81 as a mediator of resistance to proton radiation. Both proton irradiation and olaparib treatment resulted in a similar prolonged accumulation of RAD51 foci in SLX4/MUS81-deficient cells, suggesting a common defect in the repair of DNA replication fork-associated damage. Conclusions: A defect in the FA pathway at the level of SLX4 results in hypersensitivity to proton radiation, which is, at least in part, due to impaired MUS81-mediated processing of replication forks that stall at clustered DNA damage. In vivo and clinical studies are needed to

Proton decay theory

International Nuclear Information System (INIS)

Marciano, W.J.

1983-01-01

Topics include minimal SU(5) predictions, gauge boson mediated proton decay, uncertainties in tau/sub p/, Higgs scalar effects, proton decay via Higgs scalars, supersymmetric SU(5), dimension 5 operators and proton decay, and Higgs scalars and proton decay

Daily survival rates for nests of Black Skimmers from a core breeding area of the Southeastern USA

Science.gov (United States)

Brooks, Gillian L.; Sanders, Felicia J.; Gerard, Patrick D.; Jodice, Patrick G.R.

2014-01-01

Little is known about the reproductive success of Black Skimmers (Rynchops niger) throughout the southeastern USA where availability of undisturbed beaches for nesting is limited. Daily survival rates (DSR) of nests were examined at three nesting sites in Cape Romain National Wildlife Refuge (CRNWR), South Carolina, USA, 2009–2010. The percent of successful nests (n  =  346 nests) ranged from 42–69% among colony sites when data were pooled across both years. The DSR of nests was primarily related to colony site, predation risk, height of high tide, and clutch size. Predation and overwash were the principal causes of identifiable nest loss, each accounting for ∼33% of nest failures during the two study years. Because of the challenges of resighting skimmer chicks, we were not able to measure chick survival effectively and therefore accurate measures of productivity remain elusive. High variability in nest success among sites within close proximity to each other (stressors such as tropical storms or food availability. Although time-intensive techniques to control predators do exist, management options to limit flooding and overwash are far more limited. Conservation of Black Skimmers in the southeastern USA would benefit from coordinated, multi-state efforts to measure nest and chick survival.

Enhancement of erythroid colony growth in culture by hemin

International Nuclear Information System (INIS)

Porter, P.N.; Meints, R.H.; Mesner, K.

1979-01-01

Hemin was found to enhance the growth of murine erythroid colonies in culture. In the presence of 100 mU/ml erythropoietin (EPO), the addition of hemin (0.05-0.2 mM) resulted in the growth of twice as many colonies as were obtained with EPO alone. Hemin also significantly increased erythroid colony formation in culture in the absence of added EPO. Hemoblobin synthesis as measured by the incorporation of 59 Fe into cyclohexanone extractable heme was augmented in culture by hemin. Neither Δ-aminolevulinic acid, a hemin precursor, nor FeCl 3 increased colony number. (author)

[Notes about other epidemics in Colonial Chile].

Science.gov (United States)

Laval, Enrique

2015-10-01

In chronicles or in the historiography of the Colony in Chile there are few references about epidemics different to smallpox; like typhus, typhoid fever, dysentery, etc. Almost all, fast spreading in the country and some with high lethality, which led to overflowing the capacity of hospitals in the Chilean colonial period.

Impaired T-lymphocyte colony formation by cord blood mononuclear cells

International Nuclear Information System (INIS)

Herrod, H.G.; Valenski, W.R.

1982-01-01

When compared to adult mononuclear cells, cord blood mononuclear cells demonstrated significantly decreased T-lymphocyte colony formation (1351 +/- 643 vs 592 +/- 862, P less than 0.01). This diminished colony-forming activity did not appear to be associated with impaired responsiveness to the stimulant phytohemagglutinin or with excessive suppressor-cell activity. Irradiation reduced the colony-forming capacity of cord blood mononuclear cells more than it did that of adult mononuclear cells. Depletion of adherent cells reduced cord blood mononuclear-cell colony-forming capacity by 40%, while similar treatment reduced adult colony formation by 10%. Lymphocyte proliferation in liquid culture of cord and adult cells was minimally affected by these procedures. The colony-forming capacity of cord blood could be enhanced by the addition of irradiated adult cells (284 +/- 72 vs 752 +/- 78, P less than 0.01). This enhancement was demonstrated to be due to a soluble factor produced by a population of irradiated adult cells depleted of the OKT8+ subpopulation of lymphocytes. These results indicate that the progenitor cells of T-lymphocyte colonies in cord blood have distinct biologic characteristics when compared to colony progenitors present in adult blood. This assay may prove to be useful in our efforts to understand the differentiation of T-cell function in man

Vibrio harveyi effect under survival of Litopenaeus vannamei larvae

Directory of Open Access Journals (Sweden)

Gabriel Aguirre-Guzmán

2013-06-01

Full Text Available The culture of aquatic organisms show a high relevance in the human feeding and the culture activities can create artificial conditions that increase the growth and selection of specific bacteria. Vibrio species are normal bacteria’s from microflora of penaeid shrimp, those are opportunistic pathogens that can take advantage of the ecological changes generated for the culture of aquatic organisms and which may cause diseases, low survival and economic losses in the shrimp production. The aim of this research was to determine the variation in the survival of different larval substages (nauplius, zoea I-III, mysis I-III and postlarvae 1, of Pacific white shrimp Litopenaeus vannamei exposed at three doses [103 , 105 , and 107 colony-forming unit (CFU ml-1 [ of V. harveyi, by immersion (30 min as infection method. This species generated a significant low survival in larvae (p < 0.05 only in high doses (105 and 107 CFU ml-1 , where higher doses show the lowest values of survival. Larval substages and postlarvae 1 of shrimp showed sensitivity associate to the increase of Vibrio doses and this sensitivity decreased with the growth of larval substages and postlarvae 1. This information has high significance for the fisheries and aquaculture industry, which help to generate strategies to reduce the effects of V. harveyi with positive effect in growth and survival of the shrimp larvae and postlarvae 1.

Workers' Extra-Nest Behavioral Changes During Colony Fission in Dinoponera quadriceps (Santschi).

Science.gov (United States)

Medeiros, J; Araújo, A

2014-04-01

Ant colonies can reproduce by two strategies: independent foundation, wherein the queen starts a new colony alone, and dependent foundation, in which workers assist the queen. In the queenless species Dinoponera quadriceps (Santschi), the colony reproduces obligatorily by fission, a type of dependent foundation, but this process is not well understood. This study describes a colony fission event of D. quadriceps in the field and analyzes the influence of the fission process on workers' extra-nest behavior. Based on observations of workers outside the nest, five distinct stages were identified: monodomic stage, polydomic stage, split stage, conflict stage, and post-conflict stage. The colony was initially monodomic and then occupied a second nest before it split into two independent colonies, indicating a gradual and opportunistic dependent foundation. After the fission event, the daughter colony had aggressive conflicts with the parental colony, resulting in the latter's disappearance. Colony fission affected workers' extra-nest behavior by increasing the frequency of rubbing the gaster against the substrate (which probably has a chemical marking function) and by decreasing the frequency of foraging during the split stage. After the fission event, the number of foragers was halved and foragers remained nearer to the nest during extra-nest activity. The spatial closeness of the parental and daughter colonies led to competition that caused the extinction or migration of the parental colony. Intraspecific competition was indicated by foraging directionality at the colony level, whereby areas of neighbor colonies were avoided; this directionality was stronger while both colonies coexisted.

Mortality of Siberian polecats and black-footed ferrets released onto prairie dog colonies

Science.gov (United States)

Biggins, D.E.; Miller, B.J.; Hanebury, L.R.; Powell, R.A.

2011-01-01

Black-footed ferrets (Mustela nigripes) likely were extirpated from the wild in 19851986, and their repatriation depends on captive breeding and reintroduction. Postrelease survival of animals can be affected by behavioral changes induced by captivity. We released neutered Siberian polecats (M. eversmanii), close relatives of ferrets, in 19891990 on black-tailed prairie dog (Cynomys ludovicianus) colonies in Colorado and Wyoming initially to test rearing and reintroduction techniques. Captive-born polecats were reared in cages or cages plus outdoor pens, released from elevated cages or into burrows, and supplementally fed or not fed. We also translocated wild-born polecats from China in 1990 and released captive-born, cage-reared black-footed ferrets in 1991, the 1st such reintroduction of black-footed ferrets. We documented mortality for 55 of 92 radiotagged animals in these studies, mostly due to predation (46 cases). Coyotes (Canis latrans) killed 31 ferrets and polecats. Supplementally fed polecats survived longer than nonprovisioned polecats. With a model based on deaths per distance moved, survival was highest for wild-born polecats, followed by pen-experienced, then cage-reared groups. Indexes of abundance (from spotlight surveys) for several predators were correlated with mortality rates of polecats and ferrets due to those predators. Released black-footed ferrets had lower survival rates than their ancestral population in Wyoming, and lower survival than wild-born and translocated polecats, emphasizing the influence of captivity. Captive-born polecats lost body mass more rapidly postrelease than did captive-born ferrets. Differences in hunting efficiency and prey selection provide further evidence that these polecats and ferrets are not ecological equivalents in the strict sense. ?? 2011 American Society of Mammalogists.

Colonial vs planktonic type of growth: mathematical modeling of microbial dynamics on surfaces and in liquid, semi-liquid and solid foods

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Panagiotis N. Skandamis

2015-10-01

Full Text Available Predictive models are mathematical expressions that describe the growth, survival, inactivation or biochemical processes of foodborne bacteria. During processing of contaminated raw materials and food preparation, bacteria are entrapped into the food residues, potentially transferred to the equipment surfaces (abiotic or inert surfaces or cross-contaminate other foods (biotic surfaces. Growth of bacterial cells can either occur planktonically in liquid or immobilized as colonies. Colonies are on the surface or confined in the interior (submerged colonies of structured foods. For low initial levels of bacterial population leading to large colonies, the immobilized growth differs from planktonic growth due to physical constrains and to diffusion limitations within the structured foods. Indeed, cells in colonies experience substrate starvation and/or stresses from the accumulation of toxic metabolites such as lactic acid. Furthermore, the micro-architecture of foods also influences the rate and extent of growth. The micro-architecture is determined by (i the non-aqueous phase with the distribution and size of oil particles and the pore size of the network when proteins or gelling agent are solidified, and by (ii the available aqueous phase within which bacteria may swarm or swim. As a consequence, the micro-environment of bacterial cells when they grow in colonies might greatly differs from that when they grow planktonically. The broth-based data used for modeling (lag time and generation time, the growth rate and population level are poorly transferable to solid foods. It may lead to an over-estimation or under-estimation of the predicted population compared to the observed population in food. If the growth prediction concerns pathogen bacteria, it is a major importance for the safety of foods to improve the knowledge on immobilized growth. In this review, the different types of models are presented taking into account the stochastic behavior of

Disease in the Society: Infectious Cadavers Result in Collapse of Ant Sub-Colonies

Science.gov (United States)

Loreto, Raquel G.; Hughes, David P.

2016-01-01

Despite the growing number of experimental studies on mechanisms of social immunity in ant societies, little is known about how social behavior relates to disease progression within the nests of ants. In fact, when empirically studying disease in ant societies, it is common to remove dead ants from experiments to confirm infection by the studied parasite. This unfortunately does not allow disease to progress within the nest as it may be assumed would happen under natural conditions. Therefore, the approach taken so far has resulted in a limited knowledge of diseases dynamics within the nest environment. Here we introduced a single infectious cadaver killed by the fungus Beauveria bassiana into small nests of the ant Camponotus castaneus. We then observed the natural progression of the disease by not removing the corpses of the ants that died following the first entry of the disease. Because some behaviors such as social isolation of sick individuals or the removal of cadavers by nestmates are considered social immune functions and thus adaptations at the colony level that reduce disease spread, we also experimentally confined some sub-colonies to one or two chamber nests to prevent the expression of such behaviors. Based on 51 small nests and survival studies in 1,003 ants we found that a single introduced infectious cadaver was able to transmit within the nest, and social immunity did not prevent the collapse of the small sub-colonies here tested. This was true whether ants did or did not have the option to remove the infectious cadaver. Therefore, we found no evidence that the typically studied social immunity behaviors can reduce disease spread in the conditions here tested. PMID:27529548

Baryon production in proton-proton collisions

International Nuclear Information System (INIS)

Liu, F.M.; Werner, K.

2002-01-01

Motivated by the recent rapidity spectra of baryons and antibaryons in pp collisions at 158 GeV and the Ω-bar/Ω ratio discussion, we reviewed string formation mechanism and some string models. This investigation told us how color strings are formed in ultrarelativistic proton-proton collisions

Quarkonium production in high energy proton-proton and proton-nucleus collisions

International Nuclear Information System (INIS)

Conesa del Valle, Z.; Corcella, G.; Fleuret, F.; Ferreiro, E.G.; Kartvelishvili, V.; Kopeliovich, B.; Lansberg, J.P.; Lourenco, C.; Martinez, G.; Papadimitriou, V.; Satz, H.; Scomparin, E.; Ullrich, T.; Teryaev, O.; Vogt, R.; Wang, J.X.

2011-01-01

We present a brief overview of the most relevant current issues related to quarkonium production in high energy proton-proton and proton-nucleus collisions along with some perspectives. After reviewing recent experimental and theoretical results on quarkonium production in pp and pA collisions, we discuss the emerging field of polarisation studies. Afterwards, we report on issues related to heavy-quark production, both in pp and pA collisions, complemented by AA collisions. To put the work in broader perpectives, we emphasize the need for new observables to investigate the quarkonium production mechanisms and reiterate the qualities that make quarkonia a unique tool for many investigations in particle and nuclear physics.

Collecting tau neutrinos near the proton dump: an outlook

International Nuclear Information System (INIS)

Asratyan, A.Eh.; Goritchev, P.A.; Kubantsev, M.A.

1984-01-01

The possibilities for the study of tan neutrino interactions in nuclear emulsion placed close to the proton dump are discussed. The processes νsub(tay)N → taysup(-)X with subsequent taysup(-) → lν tildesub(l)νsub(tay) and taysup(-) → νsub(tay) hadrons (l=μ, e) are considered. It is shown that of the approximately 1000 event surviving the kinematic selection criteria, approximately 50 leptonic and approximately 200 hadronic tay decays can be identified in emulsion

Indonesian Chinese in the Netherlands and the legacies of violence in colonial and post-colonial Indonesia

Directory of Open Access Journals (Sweden)

Alexander van der Meer

2017-04-01

Full Text Available After Indonesian independence in 1945, thousands of Indonesian Chinese repatriated to the Netherlands, the former colonizer. As opposed to other repatriates from Indonesia, who organized themselves into pressure groups and fought for a place in the national memory culture, the Indonesian Chinese in the Netherlands only formed strict socio-cultural associations and have generally stayed clear of identity politics. Usually, this divergence is attributed to the smooth integration and socio-economic success of the latter group, as well as to Chinese values, such as conflict avoidance.This article adds to this explanation by positing that this phenomenon has also been induced by the legacy of anti-Chinese violence in colonial and post-colonial Indonesia: respectively, Dutch discomfort to acknowledge the violent and discriminatory elements of its own colonial history, as well as a fear of offending the Indonesian government. Consequently, many Indonesian Chinese in the Netherlands have engaged in some form of public self-silencing.

The underlying event in proton-proton collisions

Energy Technology Data Exchange (ETDEWEB)

Bechtel, F.

2009-05-15

In this thesis, studies of the underlying event in proton-proton collisions at a center-of-mass energy of {radical}(s) = 10 TeV are presented. Crucial ingredient to underlying event models are multiple parton-parton scatters in single proton-proton collisions. The feasibility of measuring the underlying event was investigated with the Compact Muon Solenoid (CMS) detector at the Large Hadron Collider (LHC) using charged particles and charged-particle jets. Systematic uncertainties of the underlying event measurement due to detector misalignment and imperfect track reconstruction are found to be negligible after {integral}Ldt=1 pb{sup -1} of data are available. Different model predictions are compared with each other using fully simulated Monte Carlo samples. It is found, that distinct models differ strongly enough to tell them apart with early data. (orig.)

Proteomic analysis of proton beam irradiated human melanoma cells.

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Sylwia Kedracka-Krok

Full Text Available Proton beam irradiation is a form of advanced radiotherapy providing superior distributions of a low LET radiation dose relative to that of photon therapy for the treatment of cancer. Even though this clinical treatment has been developing for several decades, the proton radiobiology critical to the optimization of proton radiotherapy is far from being understood. Proteomic changes were analyzed in human melanoma cells treated with a sublethal dose (3 Gy of proton beam irradiation. The results were compared with untreated cells. Two-dimensional electrophoresis was performed with mass spectrometry to identify the proteins. At the dose of 3 Gy a minimal slowdown in proliferation rate was seen, as well as some DNA damage. After allowing time for damage repair, the proteomic analysis was performed. In total 17 protein levels were found to significantly (more than 1.5 times change: 4 downregulated and 13 upregulated. Functionally, they represent four categories: (i DNA repair and RNA regulation (VCP, MVP, STRAP, FAB-2, Lamine A/C, GAPDH, (ii cell survival and stress response (STRAP, MCM7, Annexin 7, MVP, Caprin-1, PDCD6, VCP, HSP70, (iii cell metabolism (TIM, GAPDH, VCP, and (iv cytoskeleton and motility (Moesin, Actinin 4, FAB-2, Vimentin, Annexin 7, Lamine A/C, Lamine B. A substantial decrease (2.3 x was seen in the level of vimentin, a marker of epithelial to mesenchymal transition and the metastatic properties of melanoma.

Population regulation in Magellanic penguins: what determines changes in colony size?

Directory of Open Access Journals (Sweden)

Luciana M Pozzi

Full Text Available Seabirds are often studied at individual colonies, but the confounding effects of emigration and mortality processes in open populations may lead to inappropriate conclusions on the mechanisms underlying population changes. Magellanic penguin (Spheniscus magellanicus colonies of variable population sizes are distributed along the Argentine coastline. In recent decades, several population and distributional changes have occurred, with some colonies declining and others newly established or increasing. We integrated data of eight colonies scattered along ∼600 km in Northern Patagonia (from 41°26´S, 65°01´W to 45°11´S, 66°30´W, Rio Negro and Chubut provinces and conducted analysis in terms of their growth rates, production of young and of the dependence of those vital rates on colony age, size, and location. We contrasted population trends estimated from abundance data with those derived from population modeling to understand if observed growth rates were attainable under closed population scenarios. Population trends were inversely related to colony size, suggesting a density dependent growth pattern. All colonies located in the north--which were established during the last decades--increased at high rates, with the smallest, recently established colonies growing at the fastest rate. In central-southern Chubut, where colonies are the oldest, the largest breeding aggregations declined, but smaller colonies remained relatively stable. Results provided strong evidence that dispersal played a major role in driving local trends. Breeding success was higher in northern colonies, likely mediated by favorable oceanographic conditions. However, mean foraging distance and body condition of chicks at fledging were influenced by colony size. Recruitment of penguins in the northern area may have been triggered by a combination of density dependence, likely exacerbated by less favorable oceanographic conditions in the southern sector. Our results

Specters of Colonialism

DEFF Research Database (Denmark)

Muhr, Sara Louise; Azad, Salam

2013-01-01

at the same time they always are bound to fail to become ‘Swedish’ because of the same foreign origins. Although Swedish culture – partly by distancing itself from having a colonial past – has successfully built up an image of openness, we argue that without acknowledging and confronting the role...

Incidence, treatment, and survival patterns for sacral chordoma in the United States, 1974-2011

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Esther Yu

2016-09-01

Full Text Available IntroductionSacral chordomas represent one half of all chordomas, a rare neoplasm of notochordal remnants. Current NCCN guidelines recommend surgical resection with or without adjuvant radiotherapy, or definitive radiation for unresectable cases. Recent advances in radiation for chordomas include conformal photon and proton beam radiation. We investigated incidence, treatment, and survival outcomes to observe any trends in response to improvements in surgical and radiation techniques over a near 40 year time period.Materials and Methods345 microscopically confirmed cases of sacral chordoma were identified between 1974 and 2011 from the Surveillance, Epidemiology, and End Results (SEER program of the National Cancer Institute. Cases were divided into three cohorts by calendar year, 1974-1989, 1990-1999, and 2000-2011, as well as into two groups by age less than or equal to 65 versus greater than 65 to investigate trends over time and age via Chi-square analysis. Kaplan-Meier analyses were performed to determine effects of treatment on survival. Multivariate Cox regression analysis was performed to determine predictors of overall survival.Results5-year overall survival for the entire cohort was 60.0%. Overall survival correlated significantly with treatment modality, with 44% surviving at 5 years with no treatment, 52% with radiation alone, 82% surgery alone, and 78% surgery and radiation (p<.001. Age greater than 65 was significantly associated with non-surgical management with radiation alone or no treatment (p<.001. Relatively fewer patients received radiation between 2000 and 2011 compared to prior time periods (p=.03 versus surgery, for which rates which did not vary significantly over time (p=.55. However, 5-year overall survival was not significantly different by time period. Age group and treatment modality were predictive for overall survival on multivariate analysis (p<.001. ConclusionSurgery remains an important component in the

MUSE: Measuring the proton radius with muon-proton scattering

Energy Technology Data Exchange (ETDEWEB)

Bernauer, Jan Christopher [Massachusetts Institute of Technology, Cambridge (United States)

2014-07-01

The proton radius has been measured so far using electron-proton scattering, electronic Hydrogen spectroscopy and muonic Hydrogen spectroscopy, the latter producing a much more accurate, but seven sigma different, result, leading to the now famous proton radius puzzle. The MUSE collaboration aims to complete the set of measurements by using muon scattering to determine the proton radius and to shed light on possible explanations of the discrepancy. The talk gives an overview of the experiment motivation and design and a status report on the progress.

Seabird colonies in the Melville Bay, Northwest Greenland

DEFF Research Database (Denmark)

Boertmann, David; Huffeldt, Nicholas Per

This report describes the results of a survey for breeding and colonial seabirds in a hitherto un-surveyed area of Northwest Greenland - the Melville Bay. The results shall be included as background data for oil spill sensitivity mapping, preparation of environmental impact assessments of petroleum...... activities in Baffin Bay and for the regulation (by the Greenland government) of petroleum activities. The survey showed, that compared to other coasts of West Greenland, the Melville Bay holds only few breeding colonies and low numbers of breeding seabirds. The most widespread and numerous species...... is the black guillemot followed by the glaucous gull. However, one colony is of national significance – Sabine Øer, with high numbers of breeding Arctic terns and Sabine’s gulls. Other noteworthy observations were puffins on Thom Ø and many new Iceland gull colonies that extended the known northern breeding...

Genetic diversity within honeybee colonies increases signal production by waggle-dancing foragers

Science.gov (United States)

Mattila, Heather R; Burke, Kelly M; Seeley, Thomas D

2008-01-01

Recent work has demonstrated considerable benefits of intracolonial genetic diversity for the productivity of honeybee colonies: single-patriline colonies have depressed foraging rates, smaller food stores and slower weight gain relative to multiple-patriline colonies. We explored whether differences in the use of foraging-related communication behaviour (waggle dances and shaking signals) underlie differences in foraging effort of genetically diverse and genetically uniform colonies. We created three pairs of colonies; each pair had one colony headed by a multiply mated queen (inseminated by 15 drones) and one colony headed by a singly mated queen. For each pair, we monitored the production of foraging-related signals over the course of 3 days. Foragers in genetically diverse colonies had substantially more information available to them about food resources than foragers in uniform colonies. On average, in genetically diverse colonies compared with genetically uniform colonies, 36% more waggle dances were identified daily, dancers performed 62% more waggle runs per dance, foragers reported food discoveries that were farther from the nest and 91% more shaking signals were exchanged among workers each morning prior to foraging. Extreme polyandry by honeybee queens enhances the production of worker–worker communication signals that facilitate the swift discovery and exploitation of food resources. PMID:18198143

Proton therapy device

International Nuclear Information System (INIS)

Tronc, D.

1994-01-01

The invention concerns a proton therapy device using a proton linear accelerator which produces a proton beam with high energies and intensities. The invention lies in actual fact that the proton beam which is produced by the linear accelerator is deflected from 270 deg in its plan by a deflecting magnetic device towards a patient support including a bed the longitudinal axis of which is parallel to the proton beam leaving the linear accelerator. The patient support and the deflecting device turn together around the proton beam axis while the bed stays in an horizontal position. The invention applies to radiotherapy. 6 refs., 5 figs

Rethinking the Colonial State: Configurations of Power, Violence, and Agency

DEFF Research Database (Denmark)

Rud, Søren; Ivarsson, Søren

2017-01-01

The main theme of this special volume is the colonial state and its governmental practices. This chapter introduces and contextualizes the contributions by providing a brief induction to recent developments within the study of the colonial state. It then presents the contributions under three per...... perspectives which represent separate yet interrelated themes relevant for the understanding of the colonial state: practices, violence, and agency. Hereby, we also accentuate the value of a non-state-centric approach to the analysis of the colonial state....

Delayed protons and properties of proton-rich nuclei

International Nuclear Information System (INIS)

Karnaukhov, V.A.

1976-01-01

The object of the investigation is to study the properties of proton-rich nuclei. The emphasis in the proposed survey is made on investigations in the range of Z > 50. Measurement of the total energy in emission of delayed protons (DP) enables one to determine the difference between the masses of initial and final isotopes. The statistical model of the DP emission is used for describing the proton spectrum. A comparison of the DP experimental and theoretical spectra shows that the presence of local resonances in the strength functions of the β dacay is rather a rule than an exception. Studies into the fine structure of the proton spectra supply information of the density of nuclei considerably removed from the β-stability line at the excitation energies of 3-7 MeV. The aproaches for retrieval of nuclear information with the aid of proton radiators developed so far can serve as a good basis for systematic investigation over a wide range of A and Z

Leisure, economy and colonial urbanism: Darjeeling, 1835–1930

Science.gov (United States)

BHATTACHARYA, NANDINI

2013-01-01

This article posits that the hill station of Darjeeling was a unique form of colonial urbanism. It shifts historiographical interest from major urban centres in colonial India (such as Bombay or Calcutta) and instead attempts a greater understanding of smaller urban centres. In the process, it also interrogates the category of hill stations, which have been understood as exotic and scenic sites rather than as towns that were integral to the colonial economy. In arguing that hill stations, particularly Darjeeling, were not merely the scenic and healthy ‘other’ of the clamorous, dirty and diseased plains of India, it refutes suggestions that the ‘despoiling’ or overcrowding of Darjeeling was incremental to the purposes of its establishment. Instead, it suggests that Darjeeling was part of the colonial mainstream; its urbanization and inclusion into the greater colonial economy was effected from the time of its establishment. Therefore, a constant tension between its exotic and its functional elements persisted throughout. PMID:24273391

The importance of confronting a colonial, patriarchal and racist past ...

African Journals Online (AJOL)

The importance of confronting a colonial, patriarchal and racist past in addressing post-apartheid sexual violence. ... It also needs to redress problems of social and economic inequality that exist in South Africa as hangovers from this country's colonial and apartheid-era past. Keywords: Zuma, rape, Kipling, colonialism, ...

Genetic factors affecting radiosensitivity and cancer predisposition: application of a continuous low dose-rate irradiation colony formation assay to select radiosensitive retinoblastoma family members for correction with a cDNA library

International Nuclear Information System (INIS)

Wilson, P.F.; Nagasawa, H.; Bedford, J.S.; Little, J.B.

2003-01-01

Full text: The aim of this study is to identify new or undescribed functions of radiosensitivity and genomic instability genes using a continuous low dose-rate colony formation assay. This assay expands on the standard colony formation assay, whereby colony formation ability (retention of proliferative capacity) is measured during continuous low dose-rate irradiation rather than 10-14 days following the completion of such exposures. This approach has previously employed by the Bedford laboratory to identify a Prkdc (DNA-PKcs) mutant of CHO cells, irs-20. In this study we examine the growth response of fibroblasts derived from recently identified radiosensitive retinoblastoma family members, both affected probands and their unaffected parents, and various apparently normal fibroblast lines obtained from the NIGMS Human Genetic Cell Repository (Coriell Medical Institute, Camden, NJ). Colony formation was assayed by plating single cells, exposing them at 37 deg C to continuous Cs-137 gamma irradiation at dose rates of 0.5-8.5 cGy/h, and scoring survivors as colonies with >100 viable cells. The retinoblastoma family members display severely limited growth (survival less than 10E-3) at dose rates greater than 2-2.5 cGy/h, while the apparently normal cell lines do not display such inhibited growth until 6-7 cGy/h. Two of the retinoblastoma family cell lines, MF-6F and MF-15F (both unaffected but radiosensitive parents), were selected as targets of transfection with a viral cDNA library (ViraPort human cDNA library, Stratagene Cloning Systems, La Jolla, CA) and subjected to a ∼3 cGy/h selection dose rate, where uncorrected survival relative to normal cells is lower by a factor of 50-150. Colonies recovered will provide valuable information regarding the genetic nature of their radiosensitivity (possibly involving chromosome stability, DNA repair, and/or cell cycle regulatory pathways), that may influence risks for cancer and heritable effects for a previously

The Colonial Situation: Complicities and Distinctions from the Surrealist Image

Directory of Open Access Journals (Sweden)

Pedro Pablo Gómez

2011-05-01

Full Text Available In this work, taking as baseline the thought of Aimé Césaire and Franz Fanon —keeping in mind the closeness of the Negritude movement with surrealism—, we propose to approach the modernity/coloniality problem, appealing to the denominated surrealist image of beauty. In the first part the colonial situation is approached, in the second the colonial situation from the logic of surrealist image, and in the third the possibility of a decolonial universal or pluriversal is raised. In general terms, exploring the existent link between the “surrealist image” and the colonial structure of modernity —that generates the denominated colonial situation—, we aspire to approach what could be a decolonial aesthetic that, as general problem, will be tackled in later works.

Historicizing “Korean Criminality”: Colonial Criminality in Twentieth Century Japan

Directory of Open Access Journals (Sweden)

Joel Matthews

2017-02-01

Full Text Available In the context of Japanese colonialism, this article examines the discourse of colonial criminality that came to epistemologically position the Korean colonial subject as criminal and therefore necessitating domination, surveillance and punishment. The discourse of colonial criminality stemmed from Japan's late nineteenth century epistemological commitment to imperialism and concomitant knowledge of law and the legality of colonial subjects. Through an analysis that historicizes the “criminal Korean” (futei senjin epithet in the prewar and the emergence of yami as a signifier of Korean economic criminality throughout the 1940s, this article illustrates how the racialization of Koreans in Japan was both framed in terms of crime and subversion, and how that criminality functioned as a justification for postcolonial legalized exclusion and discrimination.

Ant Larval Demand Reduces Aphid Colony Growth Rates in an Ant-Aphid Interaction

Directory of Open Access Journals (Sweden)

James M. Cook

2012-02-01

Full Text Available Ants often form mutualistic interactions with aphids, soliciting honeydew in return for protective services. Under certain circumstances, however, ants will prey upon aphids. In addition, in the presence of ants aphids may increase the quantity or quality of honeydew produced, which is costly. Through these mechanisms, ant attendance can reduce aphid colony growth rates. However, it is unknown whether demand from within the ant colony can affect the ant-aphid interaction. In a factorial experiment, we tested whether the presence of larvae in Lasius niger ant colonies affected the growth rate of Aphis fabae colonies. Other explanatory variables tested were the origin of ant colonies (two separate colonies were used and previous diet (sugar only or sugar and protein. We found that the presence of larvae in the ant colony significantly reduced the growth rate of aphid colonies. Previous diet and colony origin did not affect aphid colony growth rates. Our results suggest that ant colonies balance the flow of two separate resources from aphid colonies- renewable sugars or a protein-rich meal, depending on demand from ant larvae within the nest. Aphid payoffs from the ant-aphid interaction may change on a seasonal basis, as the demand from larvae within the ant colony waxes and wanes.

Granulocyte colony-stimulating factor protects mice during respiratory virus infections.

Directory of Open Access Journals (Sweden)

Tamar Hermesh

Full Text Available A burst in the production of pro-inflammatory molecules characterizes the beginning of the host response to infection. Cytokines, chemokines, and growth factors work in concert to control pathogen replication and activate innate and adaptive immune responses. Granulocyte colony-stimulating factor (G-CSF mobilizes and activates hematopoietic cells from the bone marrow, and it has been shown to mediate the generation of effective immunity against bacterial and fungal infections. G-CSF is produced at high levels in the lungs during infection with influenza and parainfluenza viruses, but its role during these infections is unknown. Here we show that during infection of mice with a non-lethal dose of influenza or Sendai virus, G-CSF promotes the accumulation of activated Ly6G+ granulocytes that control the extent of the lung pro-inflammatory response. Remarkably, these G-CSF-mediated effects facilitate viral clearance and sustain mouse survival.

Toxoplasmosis in a colony of New World monkeys

DEFF Research Database (Denmark)

Dietz, H.H.; Henriksen, P.; Bille-Hansen, Vivi

1997-01-01

In a colony of New World monkeys five tamarins (Saguinus oedipus, Saguinus labiatus and Leontopithecus rosal. rosal.), three marmosets (Callithrix jacchus and Callithrix pygmaea) and one saki (Pithecia pithecia) died suddenly. The colony comprised 16 marmosets, 10 tamarins and three sakis. The ma...

Predictions of diffractive cross sections in proton-proton collisions

Energy Technology Data Exchange (ETDEWEB)

Goulianos, Konstantin [Rockefeller University, 1230 York Avenue, New York, NY 10065 (United States)

2013-04-15

We review our pre-LHC predictions of the total, elastic, total-inelastic, and diffractive components of proton-proton cross sections at high energies, expressed in the form of unitarized expressions based on a special parton-model approach to diffraction employing inclusive proton parton distribution functions and QCD color factors and compare with recent LHC results.

Abyssal fiction: common shares, colonial cleavages

Directory of Open Access Journals (Sweden)

Alexandre Montaury

2016-12-01

Full Text Available The paper aims to develop a reflection on the interaction between the legacies of colonialism and traditional symbolic and cultural practices in African Portuguese-speaking spaces. From a preliminary analysis of fictional texts of wide circulation in Brazil, aims to examine the cleavages, or “abyssal lines” that constitute experiences printed in the daily life of the former Portuguese colony of Cape Verde, Mozambique and Angola.---DOI: http://dx.doi.org/10.21881/abriluff.2016n17a378

Wintering Map for Honey Bee Colonies in El-Behera Governorate ...

African Journals Online (AJOL)

The geographical information system (GIS) has been used successfully in many studies to solve apicultural problems. The winter season is considered as a challenge for honey bee colonies due to the cold weather which cause the forfeiture of many colonies. The good wintering of honey bee colonies depends mainly on ...

Spherical proton emitters

International Nuclear Information System (INIS)

Berg, S.; Semmes, P.B.; Nazarewicz, W.

1997-01-01

Various theoretical approaches to proton emission from spherical nuclei are investigated, and it is found that all the methods employed give very similar results. The calculated decay widths are found to be qualitatively insensitive to the parameters of the proton-nucleus potential, i.e., changing the potential parameters over a fairly large range typically changes the decay width by no more than a factor of ∼3. Proton half-lives of observed heavy proton emitters are, in general, well reproduced by spherical calculations with the spectroscopic factors calculated in the independent quasiparticle approximation. The quantitative agreement with experimental data obtained in our study requires that the parameters of the proton-nucleus potential be chosen carefully. It also suggests that deformed proton emitters will provide invaluable spectroscopic information on the angular momentum decomposition of single-proton orbitals in deformed nuclei. copyright 1997 The American Physical Society

Proton therapy physics

CERN Document Server

2012-01-01

Proton Therapy Physics goes beyond current books on proton therapy to provide an in-depth overview of the physics aspects of this radiation therapy modality, eliminating the need to dig through information scattered in the medical physics literature. After tracing the history of proton therapy, the book summarizes the atomic and nuclear physics background necessary for understanding proton interactions with tissue. It describes the physics of proton accelerators, the parameters of clinical proton beams, and the mechanisms to generate a conformal dose distribution in a patient. The text then covers detector systems and measuring techniques for reference dosimetry, outlines basic quality assurance and commissioning guidelines, and gives examples of Monte Carlo simulations in proton therapy. The book moves on to discussions of treatment planning for single- and multiple-field uniform doses, dose calculation concepts and algorithms, and precision and uncertainties for nonmoving and moving targets. It also exami...

No intracolonial nepotism during colony fissioning in honey bees

Science.gov (United States)

Rangel, Juliana; Mattila, Heather R.; Seeley, Thomas D.

2009-01-01

Most species of social insects have singly mated queens, but in some species each queen mates with numerous males to create a colony whose workers belong to multiple patrilines. This colony genetic structure creates a potential for intracolonial nepotism. One context with great potential for such nepotism arises in species, like honey bees, whose colonies reproduce by fissioning. During fissioning, workers might nepotistically choose between serving a young (sister) queen or the old (mother) queen, preferring the former if she is a full-sister but the latter if the young queen is only a half-sister. We examined three honeybee colonies that swarmed, and performed paternity analyses on the young (immature) queens and samples of workers who either stayed with the young queens in the nest or left with the mother queen in the swarm. For each colony, we checked whether patrilines represented by immature queens had higher proportions of staying workers than patrilines not represented by immature queens. We found no evidence of this. The absence of intracolonial nepotism during colony fissioning could be because the workers cannot discriminate between full-sister and half-sister queens when they are immature, or because the costs of behaving nepotistically outweigh the benefits. PMID:19692398

Induction of cancer cell death by proton beam in tumor hypoxic region

International Nuclear Information System (INIS)

Hur, T. R.; Lee, Y. M.; Park, J. W.; Sohn, E. J.

2006-05-01

The physical properties of charged particles such as protons are uniquely suited to target the radiation dose precisely in the tumor. In proton therapy, the Bragg peak is spread out by modulating or degrading the energy of the particles to cover a well defined target volume at a given depth. Due to heterogeneity in the various tumors and end-points as well as in the physical properties of the beams considered, it is difficult to fit the various results into a clear general description of the biological effect of proton in tumor therapy. Tumor hypoxia is a main obstacle to radiotherapy, including gamma-ray. Survived tumor cells under hypoxic region are resistant to radiation and more aggressive to be metastasized. To investigate the dose of proton beam to induce cell death of various tumor cells and hypoxic tumor cells at the Bragg peak in vitro, we used 3 kinds of tumor cells, lung cancer, leukemia and hepatoma cells. Proton beam induces apoptosis in Lewis lung carcinoma cells dose dependently and, slightly in leukemia but not in hepatoma cells at all. Above 1000 gray of proton beam, 60% of cells died even the hypoxic cells in Lewis lung carcinoma cells. But the Molt-4 leukemia cells showed milder effect, 20% cell death by the above 1000 Gray of proton beam and typical resistant pattern (5-10%) of hypoxia in desferrioxamine treated cells. Hepatoma cells (HepG2) were not responsive to proton beam even in rather higher dose (4000G). However, by the gamma-irradiation, Molt-4 was more sensitive than hepatoma or lung cancer cells, but still showed hypoxic resistance. The cell death by proton beam in Lewis lung carcinoma cells was confirmed by PARP cleavage and may be mediated by increased p53. Pro-caspases were also activated and cleaved by the proton beam irradiations for lung cancer cell death. In conclusion, high dose of proton beam (above 1000 gray) may be a good therapeutic radiation even in hypoxic region at the Bragg peak, but further investigations about the

Tumor Cells Surviving Exposure to Proton or Photon Radiation Share a Common Immunogenic Modulation Signature, Rendering Them More Sensitive to T Cell–Mediated Killing

Energy Technology Data Exchange (ETDEWEB)

Gameiro, Sofia R.; Malamas, Anthony S. [Laboratory of Tumor Immunology and Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States); Bernstein, Michael B. [Division of Radiation Oncology, M. D. Anderson Cancer Center, Houston, Texas (United States); Tsang, Kwong Y. [Laboratory of Tumor Immunology and Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States); Vassantachart, April; Sahoo, Narayan; Tailor, Ramesh; Pidikiti, Rajesh [Division of Radiation Oncology, M. D. Anderson Cancer Center, Houston, Texas (United States); Guha, Chandan P. [Department of Radiation Oncology, Montefiore Medical Center, Bronx, New York (United States); Hahn, Stephen M.; Krishnan, Sunil [Division of Radiation Oncology, M. D. Anderson Cancer Center, Houston, Texas (United States); Hodge, James W., E-mail: jh241d@nih.gov [Laboratory of Tumor Immunology and Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (United States)

2016-05-01

Purpose: To provide the foundation for combining immunotherapy to induce tumor antigen–specific T cells with proton radiation therapy to exploit the activity of those T cells. Methods and Materials: Using cell lines of tumors frequently treated with proton radiation, such as prostate, breast, lung, and chordoma, we examined the effect of proton radiation on the viability and induction of immunogenic modulation in tumor cells by flow cytometric and immunofluorescent analysis of surface phenotype and the functional immune consequences. Results: These studies show for the first time that (1) proton and photon radiation induced comparable up-regulation of surface molecules involved in immune recognition (histocompatibility leukocyte antigen, intercellular adhesion molecule 1, and the tumor-associated antigens carcinoembryonic antigen and mucin 1); (2) proton radiation mediated calreticulin cell-surface expression, increasing sensitivity to cytotoxic T-lymphocyte killing of tumor cells; and (3) cancer stem cells, which are resistant to the direct cytolytic activity of proton radiation, nonetheless up-regulated calreticulin after radiation in a manner similar to non-cancer stem cells. Conclusions: These findings offer a rationale for the use of proton radiation in combination with immunotherapy, including for patients who have failed radiation therapy alone or have limited treatment options.

Formation of Ramified Colony of Fungus Aspergillus Oryzae on Agar Media

Science.gov (United States)

Matsuura, Shu; Miyazima, Sasuke

Ramified colonies of fungus Aspergillus oryzae have been found to grow at a low growth rate on "liquid-like" agar media with low concentrations of agar and glucose. Box-counting fractal dimensions of the individual colony branches have been found to decrease with the time of incubation. Addition of glucose solution in the interior of branched colonies has brought about the production of the hyphal filaments almost only at the apical region of the colony branches. Active growth of the ramified colonies is localized in the peripheral zone, and this growth manner implies that the fungus is exhibiting a positive exploitation.

Elastic proton-proton scattering at RHIC

Energy Technology Data Exchange (ETDEWEB)

Yip, K.

2011-09-03

Here we describe elastic proton+proton (p+p) scattering measurements at RHIC in p+p collisions with a special optics run of {beta}* {approx} 21 m at STAR, at the center-of-mass energy {radical}s = 200 GeV during the last week of the RHIC 2009 run. We present preliminary results of single and double spin asymmetries.

Military labour mobilisation in colonial Lesotho during World War II ...

African Journals Online (AJOL)

In 1940, Great Britain's wartime exploitation of the human and material resources of its colonial empire was extended to colonial Lesotho (then known as Basutoland). The aim of this article, therefore, is to trace the four-year military labour mobilisation process in that colony, with special attention to the timing, number and ...

The colonial context of Filipino American immigrants' psychological experiences.

Science.gov (United States)

David, E J R; Nadal, Kevin L

2013-07-01

Because of the long colonial history of Filipinos and the highly Americanized climate of postcolonial Philippines, many scholars from various disciplines have speculated that colonialism and its legacies may play major roles in Filipino emigration to the United States. However, there are no known empirical studies in psychology that specifically investigate whether colonialism and its effects have influenced the psychological experiences of Filipino American immigrants prior to their arrival in the United States. Further, there is no existing empirical study that specifically investigates the extent to which colonialism and its legacies continue to influence Filipino American immigrants' mental health. Thus, using interviews (N = 6) and surveys (N = 219) with Filipino American immigrants, two studies found that colonialism and its consequences are important factors to consider when conceptualizing the psychological experiences of Filipino American immigrants. Specifically, the findings suggest that (a) Filipino American immigrants experienced ethnic and cultural denigration in the Philippines prior to their U.S. arrival, (b) ethnic and cultural denigration in the Philippines and in the United States may lead to the development of colonial mentality (CM), and (c) that CM may have negative mental health consequences among Filipino American immigrants. The two studies' findings suggest that the Filipino American immigration experience cannot be completely captured by the voluntary immigrant narrative, as they provide empirical support to the notion that the Filipino American immigration experience needs to be understood in the context of colonialism and its most insidious psychological legacy- CM. PsycINFO Database Record (c) 2013 APA, all rights reserved.

A CGC/saturation approach for angular correlations in proton-proton scattering

Energy Technology Data Exchange (ETDEWEB)

Gotsman, E. [Tel Aviv University, Department of Particle Physics, School of Physics and Astronomy, Raymond and Beverly Sackler Faculty of Exact Science, Tel Aviv (Israel); Levin, E. [Tel Aviv University, Department of Particle Physics, School of Physics and Astronomy, Raymond and Beverly Sackler Faculty of Exact Science, Tel Aviv (Israel); Universidad Tecnica Federico Santa Maria, Departamento de Fisica, Valparaiso (Chile); Centro Cientifico-Tecnologico de Valparaiso, Valparaiso (Chile); Potashnikova, I. [Universidad Tecnica Federico Santa Maria, Departamento de Fisica, Valparaiso (Chile); Centro Cientifico-Tecnologico de Valparaiso, Valparaiso (Chile)

2017-09-15

We generalized our model for the description of hard processes, and calculate the value of the azimuthal angular correlations (Fourier harmonics v{sub n}), for proton-proton scattering. The energy and multiplicity independence, as well as the value of v{sub n}, turns out to be in accord with the experimental data, or slightly larger. Therefore, before making extreme assumptions on proton-proton collisions, such as the production of a quark-gluon plasma in large multiplicity events, we need to understand how these affect the Bose-Einstein correlations, which have to be taken into account since the Bose-Einstein correlations are able to describe the angular correlations in proton-proton collisions, without including final state interactions. (orig.)

Mass spectral molecular networking of living microbial colonies

NARCIS (Netherlands)

Watrous, J.; Roach, P.; Alexandrov, T.; Heath, B.S.; Yang, J.Y.; Kersten, R.D.; Voort, van der M.; Pogliano, K.; Gross, H.; Raaijmakers, J.; Moore, B.S.; Laskin, J.; Bandeira, N.; Dorrestein, P.C.

2012-01-01

Integrating the governing chemistry with the genomics and phenotypes of microbial colonies has been a “holy grail” in microbiology. This work describes a highly sensitive, broadly applicable, and cost-effective approach that allows metabolic profiling of live microbial colonies directly from a Petri

Proton-proton elastic scattering measurements at COSY

Energy Technology Data Exchange (ETDEWEB)

Bagdasarian, Zara [Forschungszentrum Juelich, Juelich (Germany); Tbilisi State University, Tbilisi (Georgia); Collaboration: ANKE-Collaboration

2014-07-01

To construct the reliable phase shift analysis (PSA) that can successfully describe the nucleon-nucleon (NN) interaction it is necessary to measure variety of experimental observables for both proton-proton (pp) and neutron-proton (np) elastic scattering. The polarized beams and targets at COSY-ANKE facility allow a substantial contribution to the existing database. The experiment was carried out in April 2013 at ANKE using a transversely polarized proton beam incident on an unpolarized hydrogen cluster target. Six beam energies of T{sub p}=0.8,1.6,1.8,2.0,2.2,2.4 GeV were used. The aim of this talk is to present the preliminary results for the analyzing power (A{sub y}) for the pp elastic scattering in the so-far unexplored 5 <θ{sub cm}<30 angular range. Our measurements are also compared to the world data and current partial wave solutions.

'Goodwill Ambassador': the Legacy of Dutch Colonial Films

Directory of Open Access Journals (Sweden)

Gerda Jansen Hendriks

2015-12-01

Full Text Available The article looks back at the films commissioned and produced by the Dutch governments about their colony in teh East-Indies between 1912 and 1962. The main focus is on the newsreels and documentaries about the colonial war between the Netherlands and Indonesia  from 1945 to 1949. The article reviews these films and the re-use of their footage in later television programs. The programs often look back at the colonial war in ways that go beyond the purpose of the original films and the article aims to show the methods that are used to do this.

Ant colony algorithm for clustering in portfolio optimization

Science.gov (United States)

Subekti, R.; Sari, E. R.; Kusumawati, R.

2018-03-01

This research aims to describe portfolio optimization using clustering methods with ant colony approach. Two stock portfolios of LQ45 Indonesia is proposed based on the cluster results obtained from ant colony optimization (ACO). The first portfolio consists of assets with ant colony displacement opportunities beyond the defined probability limits of the researcher, where the weight of each asset is determined by mean-variance method. The second portfolio consists of two assets with the assumption that each asset is a cluster formed from ACO. The first portfolio has a better performance compared to the second portfolio seen from the Sharpe index.

Physical condition and stress levels during early development reflect feeding rates and predict pre- and post-fledging survival in a nearshore seabird.

Science.gov (United States)

Lamb, Juliet S; O'Reilly, Kathleen M; Jodice, Patrick G R

2016-01-01

The effects of acute environmental stressors on reproduction in wildlife are often difficult to measure because of the labour and disturbance involved in collecting accurate reproductive data. Stress hormones represent a promising option for assessing the effects of environmental perturbations on altricial young; however, it is necessary first to establish how stress levels are affected by environmental conditions during development and whether elevated stress results in reduced survival and recruitment rates. In birds, the stress hormone corticosterone is deposited in feathers during the entire period of feather growth, making it an integrated measure of background stress levels during development. We tested the utility of feather corticosterone levels in 3- to 4-week-old nestling brown pelicans ( Pelecanus occidentalis ) for predicting survival rates at both the individual and colony levels. We also assessed the relationship of feather corticosterone to nestling body condition and rates of energy delivery to nestlings. Chicks with higher body condition and lower corticosterone levels were more likely to fledge and to be resighted after fledging, whereas those with lower body condition and higher corticosterone levels were less likely to fledge or be resighted after fledging. Feather corticosterone was also associated with intracolony differences in survival between ground and elevated nest sites. Colony-wide, mean feather corticosterone predicted nest productivity, chick survival and post-fledging dispersal more effectively than did body condition, although these relationships were strongest before fledglings dispersed away from the colony. Both reproductive success and nestling corticosterone were strongly related to nutritional conditions, particularly meal delivery rates. We conclude that feather corticosterone is a powerful predictor of reproductive success and could provide a useful metric for rapidly assessing the effects of changes in environmental

Disturbance driven colony fragmentation as a driver of a coral disease outbreak.

Directory of Open Access Journals (Sweden)

Marilyn E Brandt

Full Text Available In September of 2010, Brewer's Bay reef, located in St. Thomas (U.S. Virgin Islands, was simultaneously affected by abnormally high temperatures and the passage of a hurricane that resulted in the mass bleaching and fragmentation of its coral community. An outbreak of a rapid tissue loss disease among coral colonies was associated with these two disturbances. Gross lesion signs and lesion progression rates indicated that the disease was most similar to the Caribbean coral disease white plague type 1. Experiments indicated that the disease was transmissible through direct contact between colonies, and five-meter radial transects showed a clustered spatial distribution of disease, with diseased colonies being concentrated within the first meter of other diseased colonies. Disease prevalence and the extent to which colonies were bleached were both significantly higher on unattached colony fragments than on attached colonies, and disease occurred primarily on fragments found in direct contact with sediment. In contrast to other recent studies, disease presence was not related to the extent of bleaching on colonies. The results of this study suggest that colony fragmentation and contact with sediment played primary roles in the initial appearance of disease, but that the disease was capable of spreading among colonies, which suggests secondary transmission is possible through some other, unidentified mechanism.

Correlations associated with small angle protons produced in proton- proton collisions at 31 GeV total energy

CERN Document Server

Albrow, M G; Barber, D P; Bogaerts, A; Bosnjakovic, B; Brooks, J R; Clegg, A B; Erné, F C; Gee, C N P; Locke, D H; Loebinger, F K; Murphy, P G; Rudge, A; Sens, Johannes C

1973-01-01

High energy inelastic protons with x=2 p/sub L//s/sup 1/2/>0.99 observed in 15.3/15.3 GeV proton-proton collisions at the CERN ISR are accompanied by particles whose angular distribution is confined to a narrow cone in the opposite direction. In contrast, lower energy protons (0.72

Proton-proton reaction rates at extreme energies

International Nuclear Information System (INIS)

Nagano, Motohiko

1993-01-01

Results on proton-antiproton reaction rates (total cross-section) at collision energies of 1.8 TeV from experiments at Fermilab have suggested a lower rate of increase with energy compared to the extrapolation based on results previously obtained at CERN's proton-antiproton collider (CERN Courier, October 1991). Now an independent estimate of the values for the proton-proton total cross-section for collision energies from 5 to 30 TeV has been provided by the analysis of cosmic ray shower data collected over ten years at the Akeno Observatory operated by the Institute for Cosmic Ray Research of University of Tokyo. These results are based on the inelastic cross-section for collisions of cosmic ray protons with air nuclei at energies in the range10 16-18 eV. A new extensive air shower experiment was started at Akeno, 150 km west of Tokyo, in 1979 with a large array of detectors, both on the ground and under a 1-metre concrete absorber. This measured the total numbers of electrons and muons of energies above 1GeV for individual showers with much better accuracy than before. Data collection was almost continuous for ten years without any change in the triggering criteria for showers above10 16 eV. The mean free path for proton-air nuclei collisions has been determined from the zenith angle of the observed frequency of air showers which have the same effective path length for development in the atmosphere and the same primary energy

Spread of plague among black-tailed prairie dogs is associated with colony spatial characteristics

Science.gov (United States)

Johnson, T.L.; Cully, J.F.; Collinge, S.K.; Ray, C.; Frey, C.M.; Sandercock, B.K.

2011-01-01

Sylvatic plague (Yersinia pestis) is an exotic pathogen that is highly virulent in black-tailed prairie dogs (Cynomys ludovicianus) and causes widespread colony losses and individual mortality rates >95%. We investigated colony spatial characteristics that may influence inter-colony transmission of plague at 3 prairie dog colony complexes in the Great Plains. The 4 spatial characteristics we considered include: colony size, Euclidean distance to nearest neighboring colony, colony proximity index, and distance to nearest drainage (dispersal) corridor. We used multi-state mark-recapture models to determine the relationship between these colony characteristics and probability of plague transmission among prairie dog colonies. Annual mapping of colonies and mark-recapture analyses of disease dynamics in natural colonies led to 4 main results: 1) plague outbreaks exhibited high spatial and temporal variation, 2) the site of initiation of epizootic plague may have substantially influenced the subsequent inter-colony spread of plague, 3) the long-term effect of plague on individual colonies differed among sites because of how individuals and colonies were distributed, and 4) colony spatial characteristics were related to the probability of infection at all sites although the relative importance and direction of relationships varied among sites. Our findings suggest that conventional prairie dog conservation management strategies, including promoting large, highly connected colonies, may need to be altered in the presence of plague. ?? 2011 The Wildlife Society.

Factors of honeybee colony performances on sunflower at apiary scale

Directory of Open Access Journals (Sweden)

Kretzschmar André

2017-11-01

Full Text Available An observatory of honeybee colonies (Apis mellifera, consisting of at least 200 colonies, divided into 10 apiaries of 20 colonies, was monitored for three years on sunflower honeyflow (2015–2017. The purpose of this observatory is to understand which factors control colony performance during sunflower honeyflow in south-western France. From the temporal dynamics of weight gain, statistical analysis reveals a hierarchy of factors. First, variability in apiary scale performance is an image of the effect of resource variability. But, in addition to this primordial factor, two other factors contribute very significantly to performance. On the one hand, the amount of capped brood and the number of bees at the time of the installation of the apiary: these two elements testify to the vitality of the colony. The second remarkable factor is the Varroa load, which strongly penalizes performance beyond a certain threshold. The negative effect of the Varroa load on the colony performance is minimized in case of abondant sunflower honey flow.

Survival frequency and spectrum of induced mutations in Penicillium vermiculatum dangeard following

International Nuclear Information System (INIS)

Mitra, Jharna; Chaudhari, K.L.

1974-01-01

A comparative study on the sensitivity of UV, X-rays and gamma rays on conidia of Penicillium vermiculatum has been done. LD50 with UV-rays was shown with less than 60 second treatment at a dose of 6 x 10 3 ergs/mm 2 . Beyond 240 second treatment i.e. 2.4 x 10 4 ergs/mm 2 the survival percent remained almost the same, indicating resistance of surviving spores to the action of UV radiation. With X-rays an increase in the germination percent of conidia was noticed at dosages of 5 and 10 Kr. Abrupt fall in the survival percent was observed with increasing dosage of X-rays. A wide range of biochemical morphological mutants was obtained with UV irradiation as compared to those with X-rays. Nicotinic acid requiring mutants occurred frequently with X-rays and methionine requiring ones with gamma-rays. Compact colonial mutants were induced freely with X-rays and violet pigment producing ones with gamma-rays. (author)

Generation of mutation hotspots in ageing bacterial colonies

DEFF Research Database (Denmark)

Sekowska, Agnieszka; Wendel, Sofie; Nørholm, Morten

How do ageing bacterial colonies generate adaptive mutants? Over a period of two months, we isolated on ageing colonies outgrowing mutants able to use a new carbon source, and sequenced their genomes. This allowed us to uncover exquisite details on the molecular mechanism behind their adaptation:...

Cormorants as visitors in the Vorsø colony

DEFF Research Database (Denmark)

Bregnballe, Thomas; Vinas, Marta Mas; Gregersen, Jens

2011-01-01

Like other seabirds Great Cormorants Phalacrocorax carbo sinensis are known to prospect in potential breeding colonies during their first years of life before they settle to breed. Based on daily resightings of colour-ringed cormorants in the old Vorsø colony we examined the difference between...

Study of proton radioactivities

Energy Technology Data Exchange (ETDEWEB)

Davids, C.N.; Back, B.B.; Henderson, D.J. [and others

1995-08-01

About a dozen nuclei are currently known to accomplish their radioactive decay by emitting a proton. These nuclei are situated far from the valley of stability, and mark the very limits of existence for proton-rich nuclei: the proton drip line. A new 39-ms proton radioactivity was observed following the bombardment of a {sup 96}Ru target by a beam of 420-MeV {sup 78}Kr. Using the double-sided Si strip detector implantation system at the FMA, a proton group having an energy of 1.05 MeV was observed, correlated with the implantation of ions having mass 167. The subsequent daughter decay was identified as {sup 166}Os by its characteristic alpha decay, and therefore the proton emitter is assigned to the {sup 167}Ir nucleus. Further analysis showed that a second weak proton group from the same nucleus is present, indicating an isomeric state. Two other proton emitters were discovered recently at the FMA: {sup 171}Au and {sup 185}Bi, which is the heaviest known proton radioactivity. The measured decay energies and half-lives will enable the angular momentum of the emitted protons to be determined, thus providing spectroscopic information on nuclei that are beyond the proton drip line. In addition, the decay energy yields the mass of the nucleus, providing a sensitive test of mass models in this extremely proton-rich region of the chart of the nuclides. Additional searches for proton emitters will be conducted in the future, in order to extend our knowledge of the location of the proton drip line.

Monitoring of colonies and provisioning of rooks with nest material as a potential tool for stabilizing colonies and increasing nesting opportunities in the countryside. Project report

Directory of Open Access Journals (Sweden)

Slobodník Roman

2017-12-01

Full Text Available The rook is a species inhabiting open agricultural landscape whose non-active nests are also used by other bird species for nesting. It is the decline in rook colonies that has been posited as one of the reasons for decrease in the red-footed falcon (Falco vespertinus population in Slovakia since the 1970s. During the period from 2012 till 2016, four monitorings of rook colonies were carried out in south-western Slovakia (Diakovce, Nitrianska Osada, Sokolce and Tvrdošovce. In the colony at Tvrdošovce, supporting activity involving provisioning of rooks with nest material was under way from 2014 until 2016. While the colonies at Diakovce and Nitrianska Osada have been showing a slight decrease in the number of nesting rooks, despite larger interannual differences the colony at Sokolce has been showing an upward trend. The size of the colony at Tvrdošovce has been stable since the beginning of the supporting activity. This activity had a statistically significant positive effect on the width of rook nests. In 74 cases in the studied rook colonies we have recorded nesting by three other bird species – Eurasian kestrel (Falco tinnunculus 43.8%, western jackdaw (Corvus monedula 39.7% and long-eared owl (Asio otus 16.4%. In 2015 two female redfooted falcons were observed in the colony at Tvrdošovce.

From conquest to independence: the nigerian colonial experience

Directory of Open Access Journals (Sweden)

Tunde Oduwobi

2011-06-01

Full Text Available Este documento es un análisis panorámico de la imposición y el carácter de la administración colonial británica en Nigeria. Comienza por examinar los factores y circunstancias que facilitó la intrusión de los británicos en el área de nigeriano. El evento más importante en este desarrollo fue la conquista de los Lagos en 1851 y su incorporación formal como una colonia diez años más tarde en 1861. Simultáneamente, influencia británica propagación en el interior de Lagos y de la parte inferior del Níger. Tal, sin embargo, fue el personaje de la penetración británica que cuando en 1900 control político fue formalmente establecido sobre el área de nigeriano tomó forma tripartita de tres administraciones autónomas. Estos tres posteriormente se convirtió en amalgamados en 1914 para formar el estado de Nigeria; Sin embargo, no se borraron las tradiciones administrativas tripartitas y permanecieron como fuerzas latentes modificar el desarrollo histórico del país. Así, en el ocaso de la época colonial, nacionalismo nigeriano, desarrollando como lo fue terminar el colonialismo británico, se convirtió en adulterado negativamente por el nacionalismo étnico en los fuertes pilares de las tradiciones tripartitas fomentadas por el gobierno colonial británico. Por lo tanto el estado nigeriano surgió del colonialismo con el problema de forjar la unidad política.Palabras clave: Nigeria, colonialismo, independencia___________________________Abstract:This paper is a panoramic discussion of the imposition and character of colonial British administration in Nigeria. It begins by examining the factors and circumstances which facilitated the intrusion of the British in the Nigerian area. The most important event in this development was the conquest of the Lagos in 1851 and its formal incorporation as a colony ten years later in 1861. Concomitantly, British influence spread into the hinterland from Lagos and from the lower reaches of the

The Australian National Proton Facility

International Nuclear Information System (INIS)

Jackson, M.; Rozenfeld, A.; Bishop, J.

2002-01-01

Full text: Protons have been used in the treatment of cancer since 1954 and over 30,000 patients have been treated around the world. Their precise dose distribution allows the treatment of small tumours in critical locations such as the base of skull and orbit and is an alternative to stereotactic radiotherapy in other sites. With the development of hospital-based systems in the 1990's, common tumours such as prostate, breast and lung cancer can now also be treated using simple techniques. The therapeutic ratio is improved as the dose to the tumour can be increased while sparing normal tissues. The well defined high dose region and low integral dose compared with photon treatments is a particular advantage in children and other situations where long-term survival is expected and when used in combination with chemotherapy. In January 2002, the NSW Health Department initiated a Feasibility Study for an Australian National Proton Facility. This Study will address the complex medical, scientific, engineering, commercial and legal issues required to design and build a proton facility in Australia. The Facility will be mainly designed for patient treatment but will also provide facilities for biological, physical and engineering research. The proposed facility will have a combination of fixed and rotating beams with an energy range of 70-250 MeV. Such a centre will enable the conduct of randomised clinical trials and a comparison with other radiotherapy techniques such as Intensity Modulated Radiation Therapy. Cost-utility comparisons with other medical treatments will also be made and further facilities developed if the expected benefit is confirmed. When patients are not being treated, the beam will be available for commercial and research purposes. This presentation will summarize the progress of the Study and discuss the important issues that need to be resolved before the Facility is approved and constructed

Inductive potential of recombinant human granulocyte colony-stimulating factor to mature neutrophils from X-irradiated human peripheral blood hematopoietic progenitor cells

International Nuclear Information System (INIS)

Katsumori, Takeo; Yoshino, Hironori; Hayashi, Masako; Takahashi, Kenji; Kashiwakura, Ikuo

2009-01-01

Recombinant human granulocyte colony-stimulating factor (rhG-CSF) has been used for treatment of neutropenia. Filgrastim, Nartograstim, and Lenograstim are clinically available in Japan. However, the differences in potential benefit for radiation-induced disorder between these types of rhG-CSFs remain unknown. Therefore, the effects of three different types of rhG-CSFs on granulocyte progenitor cells and expansion of neutrophils from nonirradiated or 2 Gy X-irradiated human CD34 + hematopoietic progenitor cells were examined. For analysis of granulocyte colony-forming units (CFU-G) and a surviving fraction of CFU-G, nonirradiated or X-irradiated CD34 + cells were cultured in methylcellulose containing rhG-CSF. These cells were cultured in serum-free medium supplemented with rhG-CSF, and the expansion and characteristics of neutrophils were analyzed. All three types of rhG-CSFs increased the number of CFU-G in a dose-dependent manner; however, Lenograstim is superior to others because of CFU-G-derived colony formation at relatively low doses. The surviving fraction of CFU-G was independent of the types of rhG-CSFs. Expansion of neutrophils by rhG-CSF was largely attenuated by X-irradiation, though no significant difference in neutrophil number was observed between the three types of rhG-CSFs under both nonirradiation and X-irradiation conditions. In terms of functional characteristics of neutrophils, Lenograstim-induced neutrophils produced high levels of reactive oxygen species compared to Filgrastim, when rhG-CSF was applied to nonirradiated CD34 + cells. In conclusion, different types of rhG-CSFs lead to different effects when rhG-CSF is applied to nonirradiated CD34 + cells, though Filgrastim, Nartograstim, and Lenograstim show equal effects on X-irradiated CD34 + cells. (author)

Parametric Model for Astrophysical Proton-Proton Interactions and Applications

Energy Technology Data Exchange (ETDEWEB)

Karlsson, Niklas [KTH Royal Institute of Technology, Stockholm (Sweden)

2007-01-01

Observations of gamma-rays have been made from celestial sources such as active galaxies, gamma-ray bursts and supernova remnants as well as the Galactic ridge. The study of gamma rays can provide information about production mechanisms and cosmic-ray acceleration. In the high-energy regime, one of the dominant mechanisms for gamma-ray production is the decay of neutral pions produced in interactions of ultra-relativistic cosmic-ray nuclei and interstellar matter. Presented here is a parametric model for calculations of inclusive cross sections and transverse momentum distributions for secondary particles--gamma rays, e^±, v_e, $\\bar{v}$_e, v_μ and $\\bar{μ}$_e--produced in proton-proton interactions. This parametric model is derived on the proton-proton interaction model proposed by Kamae et al.; it includes the diffraction dissociation process, Feynman-scaling violation and the logarithmically rising inelastic proton-proton cross section. To improve fidelity to experimental data for lower energies, two baryon resonance excitation processes were added; one representing the Δ(1232) and the other multiple resonances with masses around 1600 MeV/c². The model predicts the power-law spectral index for all secondary particle to be about 0.05 lower in absolute value than that of the incident proton and their inclusive cross sections to be larger than those predicted by previous models based on the Feynman-scaling hypothesis. The applications of the presented model in astrophysics are plentiful. It has been implemented into the Galprop code to calculate the contribution due to pion decays in the Galactic plane. The model has also been used to estimate the cosmic-ray flux in the Large Magellanic Cloud based on HI, CO and gamma-ray observations. The transverse momentum distributions enable calculations when the proton distribution is anisotropic. It is shown that the gamma-ray spectrum and flux due to a

Search for Sphalerons in Proton-Proton Collisions

CERN Document Server

Ellis, John

2016-04-14

In a recent paper, Tye and Wong (TW) have argued that sphaleron-induced transitions in high-energy proton-proton collisions should be enhanced compared to previous calculations, based on a construction of a Bloch wave function in the periodic sphaleron potential and the corresponding pass band structure. Here we convolute the calculations of TW with parton distribution functions and simulations of final states to explore the signatures of sphaleron transitions at the LHC and possible future colliders. We calculate the increase of sphaleron transition rates in proton-proton collisions at centre-of-mass energies of 13/14/33/100 TeV for different sphaleron barrier heights, while recognising that the rates have large overall uncertainties. We use a simulation to show that LHC searches for microscopic black holes should have good efficiency for detecting sphaleron-induced final states, and discuss their experimental signatures and observability in Run 2 of the LHC and beyond. We recast the early ATLAS Run-2 search...

Heralding the Other: Sousa, Simulacra, and Settler Colonialism

Science.gov (United States)

Graham, Matthew C.

2016-01-01

This paper addresses the role of music and music education in the perpetuation of settler colonialism (a particular colonial configuration predicated on the expulsion of indigenous people and occupation of indigenous land) within the United States. Using Baudrillard's notion of simulacra, or "false truths," to look at racialized…

Honeybee colony marketing and its implications for queen rearing ...

African Journals Online (AJOL)

Honeybee colony marketing and its implications for queen rearing and beekeeping development in Werieleke ... Thus, colony marketing is an important venture in Werieleke district of Tigray region. ... EMAIL FULL TEXT EMAIL FULL TEXT

Response of thyroid follicular cells to gamma irradiation compared to proton irradiation: II. The role of connexin 32

Science.gov (United States)

Green, L. M.; Tran, D. T.; Murray, D. K.; Rightnar, S. S.; Todd, S.; Nelson, G. A.

2002-01-01

The objective of this study was to determine whether connexin 32-type gap junctions contribute to the "contact effect" in follicular thyrocytes and whether the response is influenced by radiation quality. Our previous studies demonstrated that early-passage follicular cultures of Fischer rat thyroid cells express functional connexin 32 gap junctions, with later-passage cultures expressing a truncated nonfunctional form of the protein. This model allowed us to assess the role of connexin 32 in radiation responsiveness without relying solely on chemical manipulation of gap junctions. The survival curves generated after gamma irradiation revealed that early-passage follicular cultures had significantly lower values of alpha (0.04 Gy(-1)) than later-passage cultures (0.11 Gy(-1)) (P 0.1, n = 9). This strongly suggests that the presence of functional connexin 32-type gap junctions was contributing to radiation resistance in gamma-irradiated thyroid follicles. Survival curves from proton-irradiated cultures had alpha values that were not significantly different whether cells expressed functional connexin 32 (0.10 Gy(-1)), did not express connexin 32 (0.09 Gy(-1)), or were down-regulated (early-passage plus heptanol, 0.09 Gy(-1); late-passage plus heptanol, 0.12 Gy(-1)) (P > 0.1, n = 19). Thus, for proton irradiation, the presence of connexin 32-type gap junctional channels did not influence their radiosensitivity. Collectively, the data support the following conclusions. (1) The lower alpha values from the gamma-ray survival curves of the early-passage cultures suggest greater repair efficiency and/or enhanced resistance to radiation-induced damage, coincident with the expression of connexin 32-type gap junctions. (2) The increased sensitivity of FRTL-5 cells to proton irradiation was independent of their ability to communicate through connexin 32 gap junctions. (3) The fact that the beta components of the survival curves from both gamma rays and proton beams were

Effects of fotemustine or dacarbasine on a melanoma cell line pretreated with therapeutic proton irradiation

Directory of Open Access Journals (Sweden)

Privitera Giuseppe

2009-04-01

Full Text Available Abstract Background Considering that HTB140 melanoma cells have shown a poor response to either protons or alkylating agents, the effects of a combined use of these agents have been analysed. Methods Cells were irradiated in the middle of the therapeutic 62 MeV proton spread out Bragg peak (SOBP. Irradiation doses were 12 or 16 Gy and are those frequently used in proton therapy. Four days after irradiation cells were treated with fotemustine (FM or dacarbazine (DTIC. Drug concentrations were 100 and 250 μM, values close to those that produce 50% of growth inhibition. Cell viability, proliferation, survival and cell cycle distribution were assessed 7 days after irradiation that corresponds to more than six doubling times of HTB140 cells. In this way incubation periods providing the best single effects of drugs (3 days and protons (7 days coincided at the same time. Results Single proton irradiations have reduced the number of cells to ~50%. FM caused stronger cell inactivation due to its high toxicity, while the effectiveness of DTIC, that was important at short term, almost vanished with the incubation of 7 days. Cellular mechanisms triggered by proton irradiation differently influenced the final effects of combined treatments. Combination of protons and FM did not improve cell inactivation level achieved by single treatments. A low efficiency of the single DTIC treatment was overcome when DTIC was introduced following proton irradiation, giving better inhibitory effects with respect to the single treatments. Most of the analysed cells were in G1/S phase, viable, active and able to replicate DNA. Conclusion The obtained results are the consequence of a high resistance of HTB140 melanoma cells to protons and/or drugs. The inactivation level of the HTB140 human melanoma cells after protons, FM or DTIC treatments was not enhanced by their combined application.

Endogenous Sheet-Averaged Tension Within a Large Epithelial Cell Colony.

Science.gov (United States)

Dumbali, Sandeep P; Mei, Lanju; Qian, Shizhi; Maruthamuthu, Venkat

2017-10-01

Epithelial cells form quasi-two-dimensional sheets that function as contractile media to effect tissue shape changes during development and homeostasis. Endogenously generated intrasheet tension is a driver of such changes, but has predominantly been measured in the presence of directional migration. The nature of epithelial cell-generated forces transmitted over supracellular distances, in the absence of directional migration, is thus largely unclear. In this report, we consider large epithelial cell colonies which are archetypical multicell collectives with extensive cell-cell contacts but with a symmetric (circular) boundary. Using the traction force imbalance method (TFIM) (traction force microscopy combined with physical force balance), we first show that one can determine the colony-level endogenous sheet forces exerted at the midline by one half of the colony on the other half with no prior assumptions on the uniformity of the mechanical properties of the cell sheet. Importantly, we find that this colony-level sheet force exhibits large variations with orientation-the difference between the maximum and minimum sheet force is comparable to the average sheet force itself. Furthermore, the sheet force at the colony midline is largely tensile but the shear component exhibits significantly more variation with orientation. We thus show that even an unperturbed epithelial colony with a symmetric boundary shows significant directional variation in the endogenous sheet tension and shear forces that subsist at the colony level.

An improved method for staining cell colonies in clonogenic assays.

Science.gov (United States)

Guda, Kishore; Natale, Leanna; Markowitz, Sanford D

2007-06-01

Clonogenic assay is a widely used experimental approach to test for the effects of drugs/genes on the growth and proliferative characteristics of cells in vitro. Accurate quantitation of treatment effects in clonogeneic assays depends on the ability to visualize and count cell colonies precisely. We report a novel method (referred as ETeB) for staining cell colonies grown on plastic and specially coated substrates like collagen. Using colon cancer cell lines grown on plastic and collagen, we compared the colony staining efficiencies of the widely used methylene blue, and Ethidium bromide (ETeB) stains. Results show that the ETeB protocol works well on plastic and is extremely effective for staining colonies on collagen when compared to methylene blue. The key features and advantages of ETeB technique are; (a) reduction in background for colonies grown on collagen and possibly other substrates, (b) the whole procedure takes less than a minute, (c) no post-stain washing step is required which eliminates colony losses for cell lines that are loosely adherent, (d) colony visualization and counting can be done immediately following the staining procedure using a standard UV illuminator and software, and (e) the method works across a wide variety of cell lines. The simplicity and robustness of this procedure should warrant its usage in both small and large-scale clonogenic experiments.

From 2D to 3D: Proton Radiography and Proton CT in proton therapy: A simulation study

NARCIS (Netherlands)

Takatsu, J.; van der Graaf, E.R.; van Goethem, M.-J.; Brandenburg, S.; Biegun, Aleksandra

(1) Purpose In order to reduce the uncertainty in translation of the X-ray Computed Tomography (CT) image into a map of proton stopping powers (3-4% and even up to 10% in regions containing bones [1-8]), proton radiography is being studied as an alternative imaging technique in proton therapy. We

Vibrational spectroscopy on protons and deuterons in proton conducting perovskites

DEFF Research Database (Denmark)

Glerup, M.; Poulsen, F.W.; Berg, R.W.

2002-01-01

A short review of IR-spectroscopy on protons in perovskite structure oxides is given. The nature of possible proton sites, libration and combination tones and degree of hydrogen bonding is emphasised. Three new spectroscopic experiments and/or interpretations are presented. An IR-microscopy exper......A short review of IR-spectroscopy on protons in perovskite structure oxides is given. The nature of possible proton sites, libration and combination tones and degree of hydrogen bonding is emphasised. Three new spectroscopic experiments and/or interpretations are presented. An IR...

Use of primary cell cultures to measure the late effects in the skins of rhesus monkeys irradiated with protons

Science.gov (United States)

Cox, A. B.; Wood, D. H.; Lett, J. T.

Previous pilot investigations of the uses of primary cell cultures to study late damage in stem cells of the skin of the New Zealand white (NZW) rabbit and the rhesus monkey /1-3/, have been extended to individual monkeys exposed to 55 MeV protons. Protons of this energy have a larger range in tissue of (~2.6 cm) than the 32 MeV protons (~0.9 cm) to which the animals in our earlier studies had been exposed. Although the primary emphases in the current studies were improvement and simplification in the techniques and logistics of transportation of biopsies to a central analytical facility, comparison of the quantitative measurements obtained thus far for survival of stem cells in the skins from animals irradiated 21 years ago reveals that the effects of both proton energies are similar.

A rationale for the use of proton pump inhibitors as antineoplastic agents.

Science.gov (United States)

De Milito, Angelo; Marino, Maria Lucia; Fais, Stefano

2012-01-01

It is becoming increasingly acknowledged that tumorigenesis is not simply characterized by the accumulation of rapidly proliferating, genetically mutated cells. Microenvironmental biophysical factors like hypoxia and acidity dramatically condition cancer cells and act as selective forces for malignant cells, adapting through metabolic reprogramming towards aerobic glycolysis. Avoiding intracellular accumulation of lactic acid and protons, otherwise detrimental to cell survival is crucial for malignant cells to maintain cellular pH homeostasis. As a consequence of the upregulated expression and/or function of several pH-regulating systems, cancer cells display an alkaline intracellular pH (pHi) and an acidic extracellular pH (pHe). Among the pH-regulating proteins, proton pumps play an important role in both drug-resistance and metastatic spread, thus representing a suitable therapeutic target. Proton pump inhibitors (PPI) have been reported as cytotoxic drugs active against several human tumor cells and preclinical data have prompted the investigation of PPI as anticancer agents in humans. This review will update the current knowledge on the antitumor activities of PPI and their potential applications.

Redox state, reactive oxygen species and adaptive growth in colonial hydroids.

Science.gov (United States)

Blackstone, N W

2001-06-01

Colonial metazoans often encrust surfaces over which the food supply varies in time or space. In such an environment, adaptive colony development entails adjusting the timing and spacing of feeding structures and gastrovascular connections to correspond to this variable food supply. To investigate the possibility of such adaptive growth, within-colony differential feeding experiments were carried out using the hydroid Podocoryna carnea. Indeed, such colonies strongly exhibited adaptive growth, developing dense arrays of polyps (feeding structures) and gastrovascular connections in areas that were fed relative to areas that were starved, and this effect became more consistent over time. To investigate mechanisms of signaling between the food supply and colony development, measurements were taken of metabolic parameters that have been implicated in signal transduction in other systems, particularly redox state and levels of reactive oxygen species. Utilizing fluorescence microscopy of P. carnea cells in vivo, simultaneous measurements of redox state [using NAD(P)H] and hydrogen peroxide (using 2',7'-dichlorofluorescin diacetate) were taken. Both measures focused on polyp epitheliomuscular cells, since these exhibit the greatest metabolic activity. Colonies 3-5h after feeding were relatively oxidized, with low levels of peroxide, while colonies 24h after feeding were relatively reduced, with high levels of peroxide. The functional role of polyps in feeding and generating gastrovascular flow probably produced this dichotomy. Polyps 3-5h after feeding contract maximally, and this metabolic demand probably shifts the redox state in the direction of oxidation and diminishes levels of reactive oxygen species. In contrast, 24h after feeding, polyps are quiescent, and this lack of metabolic demand probably shifts the redox state in the direction of reduction and increases levels of reactive oxygen species. Within-colony differential feeding experiments were carried out on

Colonial Modernity and the African Worldview: Theorising and ...

African Journals Online (AJOL)

concept of hegemony and Jean and John Comaroff's concept of cultural and colonial encounters are used to assist in teasing out deeper meaning in the encounter between the Ndebele and the early Christian missionaries prior to inscription of settler colonialism in the area lying between the Limpopo and Zambezi Rivers.

Embodying colonial photography: remembering violence in Tabee Toean

NARCIS (Netherlands)

Bijl, P.

2011-01-01

This article is about bodily interactions with photographs. Taking an interview with a veteran from the Dutch colonial army filmed for the documentary Tabee Toean (1995) as its case study, it focuses on the ways in which this man frames these images of colonial warfare through three types of bodily