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Sample records for colonial portuguesa pelos

  1. Colonial America.

    ERIC Educational Resources Information Center

    Web Feet K-8, 2001

    2001-01-01

    Presents resources for grades K-8, on the subject of Colonial America. Describes Web sites; CD-ROMs and software; videos; books; audios; magazines; and professional resources. Includes two articles, "Native Americans in the Colonies," and "The Golden Age of Pirates," which also highlight resources. Presents a Web activity focusing on daily life in…

  2. The Amana Colonies.

    ERIC Educational Resources Information Center

    Lilja, Marilyn

    Designed for use in Iowa elementary schools, this unit introduces students to Iowa's Amana Colonies. Four lessons cover the history and cultural heritage of the colonies, daily life in historical times, daily life in modern times, and the colonies as a corporate museum. Throughout the lessons, emphasis is placed on the values and organization of…

  3. The Amana Colonies.

    ERIC Educational Resources Information Center

    Lilja, Marilyn

    Designed for use in Iowa elementary schools, this unit introduces students to Iowa's Amana Colonies. Four lessons cover the history and cultural heritage of the colonies, daily life in historical times, daily life in modern times, and the colonies as a corporate museum. Throughout the lessons, emphasis is placed on the values and organization of…

  4. Social Studies; Colonial America.

    ERIC Educational Resources Information Center

    Hanson, Paul S.

    Students in grades seven through nine will examine and analyze the political organization, social structure, economic life, and values of the American Colonial period in this quinmester arranged American Studies course. Since the thirteen English Colonies effected the United States development, many of our nations foundations in government,…

  5. Robotic space colonies

    NASA Technical Reports Server (NTRS)

    Schenker, P.; Easter, R.; Rodriguez, G.

    2001-01-01

    This paper reviews recent advances in these technologies, with a particular focus on experimental state-of-the-art robot work crew system demonstrations at JPL, that are being conducted now to begin to realize the futuristic robotic colony vision.

  6. Growth of Bacterial Colonies

    NASA Astrophysics Data System (ADS)

    Warren, Mya; Hwa, Terence

    2013-03-01

    On hard agar gel, there is insufficient surface hydration for bacteria to swim or swarm. Instead, growth occurs in colonies of close-packed cells, which expand purely due to repulsive interactions: individual bacteria push each other out of the way through the force of their growth. In this way, bacterial colonies represent a new type of ``active'' granular matter. In this study, we investigate the physical, biochemical, and genetic elements that determine the static and dynamic aspects of this mode of bacterial growth for E. coli. We characterize the process of colony expansion empirically, and use discrete and continuum models to examine the extent to which our observations can be explained by the growth characteristics of non-communicating cells, coupled together by physical forces, nutrients, and waste products. Our results challenge the commonly accepted modes of bacterial colony growth and provide insight into sources of growth limitation in crowded bacterial communities.

  7. Plymouth Colony, Massachusetts, USA

    NASA Image and Video Library

    1990-03-04

    Site of the original Plymouth Colony in Massachusetts (42.0N, 70.5), This detailed photo is rich in early American history. Plymouth Rock, the Pilgrims first stepping stone on North America and site of Plymouth Colony is located just behind the natural breakwater on the south shore of Plymouth Bay seen in the middle of the photo. The through canal to the south is part of the Intercoastal Canal system. Cape Cod is just south of the canal.

  8. Plymouth Colony, Massachusetts, USA

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Site of the original Plymouth Colony in Massachusetts (42.0N, 70.5), This detailed photo is rich in early American history. Plymouth Rock, the Pilgrims first stepping stone on North America and site of Plymouth Colony is located just behind the natural breakwater on the south shore of Plymouth Bay seen in the middle of the photo. The through canal to the south is part of the Intercoastal Canal system. Cape Cod is just south of the canal.

  9. Colony Collapse Disorder

    EPA Pesticide Factsheets

    In CCD, the majority of worker bees in a colony disappear and leave behind a queen, plenty of food and a few nurse bees to care for remaining immature bees and the queen. EPA and USDA are working to understand and resolve this problem.

  10. Sailing to the Colonies.

    ERIC Educational Resources Information Center

    Carter, Dorothy S.

    1990-01-01

    Presents a class activity designed to foster an understanding of rules, develop analytical skills, and introduce students to early colonial history. Divides the class into groups who are sailing to the New World, and presents them with ethical and practical problems to be solved on board the ship. (RW)

  11. Colonial American Astronomy

    NASA Astrophysics Data System (ADS)

    Yeomans, Donald K.

    2007-12-01

    While a foundation of German scientific methods enabled the rapid growth of North American Astronomy in the nineteenth century, during the seventeenth and most of the eighteenth centuries, the colonial men of science looked only to the English mother country for scientific patronage and guidance. An essay on fundamental astronomy appeared in one of the annual colonial almanacs as early as 1656, telescopic observations were made about 1660 and the first original colonial astronomical work was published by Thomas Danforth on the comet of 1664. By 1671 the Copernican ideas were so espoused at Harvard College that a physics class refused to read a Ptolemaic textbook when it was assigned to them by a senior instructor. At least in the Cambridge-Boston area, contemporary colonialist had access to the most recent scientific publications from the mother country. Observations of the great comet of 1680 by the Almanac maker, John Foster, reached Isaac Newton and were used and gratefully acknowledged in his Principia. During the seventeenth century the colonial interest in astronomy was more intense than it was for other sciences but colonists still occupied a position in the scientific backwater when compared with contemporary European scientists. Nevertheless, the science of astronomy was successfully transplanted from England to North America in the seventeenth century.

  12. [Visiting the Amana Colonies.

    ERIC Educational Resources Information Center

    Ohrn, Deborah Gore, Ed.

    1992-01-01

    This issue of "The Goldfinch: Iowa History for Young People" focuses upon the Amana Colonies, which were home to many German immigrants in the 19th century, and which retain much of their ethnic heritage today. The articles and activities included in this issue are "Amana Today"; "No Black Buggies in Amana";…

  13. Colony image acquisition and genetic segmentation algorithm and colony analyses

    NASA Astrophysics Data System (ADS)

    Wang, W. X.

    2012-01-01

    Colony anaysis is used in a large number of engineerings such as food, dairy, beverages, hygiene, environmental monitoring, water, toxicology, sterility testing. In order to reduce laboring and increase analysis acuracy, many researchers and developers have made efforts for image analysis systems. The main problems in the systems are image acquisition, image segmentation and image analysis. In this paper, to acquire colony images with good quality, an illumination box was constructed. In the box, the distances between lights and dishe, camra lens and lights, and camera lens and dishe are adjusted optimally. In image segmentation, It is based on a genetic approach that allow one to consider the segmentation problem as a global optimization,. After image pre-processing and image segmentation, the colony analyses are perfomed. The colony image analysis consists of (1) basic colony parameter measurements; (2) colony size analysis; (3) colony shape analysis; and (4) colony surface measurements. All the above visual colony parameters can be selected and combined together, used to make a new engineeing parameters. The colony analysis can be applied into different applications.

  14. Fever in honeybee colonies

    NASA Astrophysics Data System (ADS)

    Starks, P. T.; Blackie, Caroline A.; Seeley, Thomas D.

    Honeybees, Apis spp., maintain elevated temperatures inside their nests to accelerate brood development and to facilitate defense against predators. We present an additional defensive function of elevating nest temperature: honeybees generate a brood-comb fever in response to colonial infection by the heat-sensitive pathogen Ascosphaera apis. This response occurs before larvae are killed, suggesting that either honeybee workers detect the infection before symptoms are visible, or that larvae communicate the ingestion of the pathogen. This response is a striking example of convergent evolution between this "superorganism" and other fever-producing animals.

  15. Colony image acquisition and segmentation

    NASA Astrophysics Data System (ADS)

    Wang, W. X.

    2007-12-01

    For counting of both colonies and plaques, there is a large number of applications including food, dairy, beverages, hygiene, environmental monitoring, water, toxicology, sterility testing, AMES testing, pharmaceuticals, paints, sterile fluids and fungal contamination. Recently, many researchers and developers have made efforts for this kind of systems. By investigation, some existing systems have some problems. The main problems are image acquisition and image segmentation. In order to acquire colony images with good quality, an illumination box was constructed as: the box includes front lightning and back lightning, which can be selected by users based on properties of colony dishes. With the illumination box, lightning can be uniform; colony dish can be put in the same place every time, which make image processing easy. The developed colony image segmentation algorithm consists of the sub-algorithms: (1) image classification; (2) image processing; and (3) colony delineation. The colony delineation algorithm main contain: the procedures based on grey level similarity, on boundary tracing, on shape information and colony excluding. In addition, a number of algorithms are developed for colony analysis. The system has been tested and satisfactory.

  16. Colony Dimorphism in Bradyrhizobium Strains

    PubMed Central

    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

  17. Colony collapse disorder in Europe.

    PubMed

    Dainat, Benjamin; Vanengelsdorp, Dennis; Neumann, Peter

    2012-02-01

    Colony collapse disorder (CCD) is a condition of honey bees, which has contributed in part to the recent major losses of honey bee colonies in the USA. Here we report the first CCD case from outside of the USA. We suggest that more standardization is needed for the case definition to diagnose CCD and to compare data on a global scale.

  18. Student Discipline in Colonial America.

    ERIC Educational Resources Information Center

    Petry, John R.

    The basis for the severe discipline imposed on school children in colonial America, especially in the Puritan colonies, was the belief in original sin. The child was regarded as being born in sin and thus depraved and prone to sin. The purpose of education was to enable children to read the Bible and thus change the behavior which otherwise would…

  19. Post-Colonial Theory and Action Research

    ERIC Educational Resources Information Center

    Parsons, Jim B.; Harding, Kelly J.

    2011-01-01

    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…

  20. Stories, skulls, and colonial collections.

    PubMed

    Roque, Ricardo

    2011-01-01

    The essay explores the hypothesis of colonial collecting processes involving the active addition of the colonial context and historical past to museum objects through the production of short stories. It examines the emergent historicity of collections through a focus on the "histories" that museum workers and colonial agents have been attaching to scientific collections of human skulls. Drawing on the notions of collection trajectory and historiographical work, it offers an alternative perspective from which to approach the creation of singular histories and individual archives for objects in collections.

  1. Genetic diversity affects colony survivorship in commercial honey bee colonies.

    PubMed

    Tarpy, David R; Vanengelsdorp, Dennis; Pettis, Jeffrey S

    2013-08-01

    Honey bee (Apis mellifera) queens mate with unusually high numbers of males (average of approximately 12 drones), although there is much variation among queens. One main consequence of such extreme polyandry is an increased diversity of worker genotypes within a colony, which has been shown empirically to confer significant adaptive advantages that result in higher colony productivity and survival. Moreover, honey bees are the primary insect pollinators used in modern commercial production agriculture, and their populations have been in decline worldwide. Here, we compare the mating frequencies of queens, and therefore, intracolony genetic diversity, in three commercial beekeeping operations to determine how they correlate with various measures of colony health and productivity, particularly the likelihood of queen supersedure and colony survival in functional, intensively managed beehives. We found the average effective paternity frequency (m e ) of this population of honey bee queens to be 13.6 ± 6.76, which was not significantly different between colonies that superseded their queen and those that did not. However, colonies that were less genetically diverse (headed by queens with m e  ≤ 7.0) were 2.86 times more likely to die by the end of the study when compared to colonies that were more genetically diverse (headed by queens with m e  > 7.0). The stark contrast in colony survival based on increased genetic diversity suggests that there are important tangible benefits of increased queen mating number in managed honey bees, although the exact mechanism(s) that govern these benefits have not been fully elucidated.

  2. Genetic diversity affects colony survivorship in commercial honey bee colonies

    NASA Astrophysics Data System (ADS)

    Tarpy, David R.; vanEngelsdorp, Dennis; Pettis, Jeffrey S.

    2013-08-01

    Honey bee ( Apis mellifera) queens mate with unusually high numbers of males (average of approximately 12 drones), although there is much variation among queens. One main consequence of such extreme polyandry is an increased diversity of worker genotypes within a colony, which has been shown empirically to confer significant adaptive advantages that result in higher colony productivity and survival. Moreover, honey bees are the primary insect pollinators used in modern commercial production agriculture, and their populations have been in decline worldwide. Here, we compare the mating frequencies of queens, and therefore, intracolony genetic diversity, in three commercial beekeeping operations to determine how they correlate with various measures of colony health and productivity, particularly the likelihood of queen supersedure and colony survival in functional, intensively managed beehives. We found the average effective paternity frequency ( m e ) of this population of honey bee queens to be 13.6 ± 6.76, which was not significantly different between colonies that superseded their queen and those that did not. However, colonies that were less genetically diverse (headed by queens with m e ≤ 7.0) were 2.86 times more likely to die by the end of the study when compared to colonies that were more genetically diverse (headed by queens with m e > 7.0). The stark contrast in colony survival based on increased genetic diversity suggests that there are important tangible benefits of increased queen mating number in managed honey bees, although the exact mechanism(s) that govern these benefits have not been fully elucidated.

  3. Colony spreading in Staphylococcus aureus.

    PubMed

    Kaito, Chikara; Sekimizu, Kazuhisa

    2007-03-01

    Wild-type Staphylococcus aureus rapidly expands on the surface of soft agar plates. The rates of expansion and the shapes of the resultant giant colonies were distinct for different strains of laboratory stocks and clinical isolates. The colony spreading abilities did not correlate with the biofilm-forming abilities in these strains. Insertional disruption of the dltABCD operon, which functions at the step of D-alanine addition to teichoic acids, and of the tagO gene, which is responsible for the synthesis of wall teichoic acids, decreased the colony spreading ability. The results indicate that wall teichoic acids and D-alanylation of teichoic acids are required for colony spreading.

  4. [Vertebrate mortality in the Guanare-Guanarito road, Portuguesa state, Venezuela].

    PubMed

    Seijas, Andrés Eloy; Araujo-Quintero, Alexis; Velásquez, Nadines

    2013-12-01

    Roads directly or indirectly affect the structure, dynamics and function of ecosystems that they traverse. Most studies on the effect of roads on wildlife focus on the evaluation of mortality of vertebrates by vehicle collisions. Despite the extensive road network that exists in Venezuela, studies of wildlife mortality in them are scarce. In this paper, we analyzed the temporal and spatial pattern of vertebrate's collisions along the road Guanare-Guanarito, in Portuguesa state. We travelled 26 times between these towns (74 km) to localize dead vertebrates, at a speed of 50-60km/h. of those trips were conducted from March 13 to October 26, 2010, and 10 additional trips from December 7, 2009 to December 14, 2010; these ones, with the aim to include months and seasons that were insufficiently sampled during the first period. The elapsed time between trips varied from 14 to 37 days. The total distance traveled was 1 924 km. Dead animals found amounted 464 individuals, 66 of them were birds (25 identified species), 130 mammals (15 species) and 268 reptiles (18 species). The species with the highest number of individuals were the snake Leptodeira annulata (n=119), the oppossum Didelphis marsupialis (n=39) and the spectacled caiman Caiman crocodilus (n=33). Excluding domestic animals, the rate of road-killed vertebrates was 0.2282 indiv./km, a figure 28.3% higher than previous studies in the same road. Changes in the relative number of collisions for some species, respect to the numbers reported 20 years ago, were linked to the increase in traffic flow and changes in land use. Road segments with collision rates higher than expected by chance were identified. Collition by cars may be the principal cause of mortality for species like the tamandua (Tamandua tetradactyla) and the giant anteater (Myrmecophaga tridactyla), the last considered a vulnerable species. Some basic measures are proposed to reduce wildlife mortality on the road.

  5. Colonialism in Africa: A Critical Look!

    ERIC Educational Resources Information Center

    Gage, Susan

    Using text, activities, cartoons, and prose, the publication encourages junior and senior secondary students to examine the history of colonialism in Africa and the importance of colonialism in Africa today. Chapter 1 provides an overview of 500 years of colonialism. Chapter 2 describes pre-colonial Africa from the year 1000 to 1442. The focus of…

  6. Colonialism in Africa: A Critical Look!

    ERIC Educational Resources Information Center

    Gage, Susan

    Using text, activities, cartoons, and prose, the publication encourages junior and senior secondary students to examine the history of colonialism in Africa and the importance of colonialism in Africa today. Chapter 1 provides an overview of 500 years of colonialism. Chapter 2 describes pre-colonial Africa from the year 1000 to 1442. The focus of…

  7. Periodic growth of bacterial colonies

    NASA Astrophysics Data System (ADS)

    Yamazaki, Yoshihiro; Ikeda, Takemasa; Shimada, Hirotoshi; Hiramatsu, Fumiko; Kobayashi, Naoki; Wakita, Jun-ichi; Itoh, Hiroto; Kurosu, Sayuri; Nakatsuchi, Michio; Matsuyama, Tohey; Matsushita, Mitsugu

    2005-06-01

    The formation of concentric ring colonies by bacterial species Bacillus subtilis and Proteus mirabilis has been investigated experimentally, focusing our attention on the dependence of local cell density upon the bacterial motility. It has been confirmed that these concentric ring colonies reflect the periodic change of the bacterial motility between motile cell state and immotile cell state. We conclude that this periodic change is macroscopically determined neither by biological factors (i.e., biological clock) nor by chemical factors (chemotaxis as inhibitor). And our experimental results strongly suggest that the essential factor for the change of the bacterial motility during concentric ring formation is the local cell density.

  8. Genetic diversity affects colony survivorship in commercial honey bee colonies

    USDA-ARS?s Scientific Manuscript database

    Honey bee (Apis mellifera) queens mate with unusually high numbers of males (average of approximately 12 drones), although there is much variation among queens. One main consequence of such extreme polyandry is an increased diversity of worker genotypes within a colony, which has been shown empirica...

  9. Chronic sublethal stress causes bee colony failure

    PubMed Central

    Bryden, John; Gill, Richard J; Mitton, Robert A A; Raine, Nigel E; Jansen, Vincent A A; Hodgson, David

    2013-01-01

    Current bee population declines and colony failures are well documented yet poorly understood and no single factor has been identified as a leading cause. The evidence is equivocal and puzzling: for instance, many pathogens and parasites can be found in both failing and surviving colonies and field pesticide exposure is typically sublethal. Here, we investigate how these results can be due to sublethal stress impairing colony function. We mathematically modelled stress on individual bees which impairs colony function and found how positive density dependence can cause multiple dynamic outcomes: some colonies fail while others thrive. We then exposed bumblebee colonies to sublethal levels of a neonicotinoid pesticide. The dynamics of colony failure, which we observed, were most accurately described by our model. We argue that our model can explain the enigmatic aspects of bee colony failures, highlighting an important role for sublethal stress in colony declines. PMID:24112478

  10. Chronic sublethal stress causes bee colony failure.

    PubMed

    Bryden, John; Gill, Richard J; Mitton, Robert A A; Raine, Nigel E; Jansen, Vincent A A

    2013-12-01

    Current bee population declines and colony failures are well documented yet poorly understood and no single factor has been identified as a leading cause. The evidence is equivocal and puzzling: for instance, many pathogens and parasites can be found in both failing and surviving colonies and field pesticide exposure is typically sublethal. Here, we investigate how these results can be due to sublethal stress impairing colony function. We mathematically modelled stress on individual bees which impairs colony function and found how positive density dependence can cause multiple dynamic outcomes: some colonies fail while others thrive. We then exposed bumblebee colonies to sublethal levels of a neonicotinoid pesticide. The dynamics of colony failure, which we observed, were most accurately described by our model. We argue that our model can explain the enigmatic aspects of bee colony failures, highlighting an important role for sublethal stress in colony declines. © 2013 The Authors. Ecology Letters published by John Wiley & Sons Ltd and CNRS.

  11. Recent Honey Bee Colony Declines

    DTIC Science & Technology

    2007-03-26

    Population Losses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Symptoms of Colony Collapse Disorder...MAAREC), which represents beekeeping associations in New Jersey, Maryland, Delaware, Pennsylvania, and West Virginia. Past Honey Bee Population Losses... population losses due to bee pests, parasites, pathogens, and disease. Most notable are declines due to two parasitic mites, the Varroa destructor and the

  12. Recent Honey Bee Colony Declines

    DTIC Science & Technology

    2007-06-20

    sustain wildlife populations ; emphasizing the importance of pollinator diversity and sustaining wild and native pollinator species; developing or...Bee Population Losses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Recent Colony Losses from Available Surveys...www.masterbeekeeper.org/pdf/ pollination.pdf]. Source: Bee Alert Inc., [http://www.beealert.info/]. Shaded areas show reported affected states. Past Honey Bee Population

  13. The Vine and Olive Colony.

    ERIC Educational Resources Information Center

    Albinski, Nan Bowman

    1985-01-01

    Traces the historical sources of "Some Plant Olive Trees," a utopian novel by Emma Gelders Sterne, which offers a fictional account of the Vine and Olive colony, one of the most colorful yet least known utopian communities of the nineteenth century. (AYC)

  14. The Vine and Olive Colony.

    ERIC Educational Resources Information Center

    Albinski, Nan Bowman

    1985-01-01

    Traces the historical sources of "Some Plant Olive Trees," a utopian novel by Emma Gelders Sterne, which offers a fictional account of the Vine and Olive colony, one of the most colorful yet least known utopian communities of the nineteenth century. (AYC)

  15. Ant colony optimization: Introduction and recent trends

    NASA Astrophysics Data System (ADS)

    Blum, Christian

    2005-12-01

    Ant colony optimization is a technique for optimization that was introduced in the early 1990's. The inspiring source of ant colony optimization is the foraging behavior of real ant colonies. This behavior is exploited in artificial ant colonies for the search of approximate solutions to discrete optimization problems, to continuous optimization problems, and to important problems in telecommunications, such as routing and load balancing. First, we deal with the biological inspiration of ant colony optimization algorithms. We show how this biological inspiration can be transfered into an algorithm for discrete optimization. Then, we outline ant colony optimization in more general terms in the context of discrete optimization, and present some of the nowadays best-performing ant colony optimization variants. After summarizing some important theoretical results, we demonstrate how ant colony optimization can be applied to continuous optimization problems. Finally, we provide examples of an interesting recent research direction: The hybridization with more classical techniques from artificial intelligence and operations research.

  16. Colonialism in the Americas: A Critical Look!

    ERIC Educational Resources Information Center

    Gage, Susan

    Dialogue and illustrations trace the history of the first peoples of South, Central, and North America and encourage students to look at past and present patterns of colonialism and to view colonialism from the perspective of the colonized. Chapter 1 critiques Columbus 500 years after founding the first colony in the Americas. Chapter 2 presents…

  17. One Kilogram Interstellar Colony Mission

    NASA Astrophysics Data System (ADS)

    Mole, A.

    Small interstellar colony probes based on nanotechnology will become possible long before giant multi-generation ships become affordable. A beam generator and magnetic sail can accelerate a one kg probe to .1 c, braking via the interstellar field can decelerate it, and the field in a distant solar system can allow it to maneuver to an extrasolar planet. A heat shield is used for landing and nanobots emerge to build ever-larger robots and construct colony infrastructure. Humans can then be generated from genomes stored as data in computer memory. Technology is evolving towards these capabilities and should reach the required level in fifty years. The plan appears to be affordable, with the principal cost being the beam generator, estimated at $17 billion.

  18. Exploration adjustment by ant colonies

    PubMed Central

    2016-01-01

    How do animals in groups organize their work? Division of labour, i.e. the process by which individuals within a group choose which tasks to perform, has been extensively studied in social insects. Variability among individuals within a colony seems to underpin both the decision over which tasks to perform and the amount of effort to invest in a task. Studies have focused mainly on discrete tasks, i.e. tasks with a recognizable end. Here, we study the distribution of effort in nest seeking, in the absence of new nest sites. Hence, this task is open-ended and individuals have to decide when to stop searching, even though the task has not been completed. We show that collective search effort declines when colonies inhabit better homes, as a consequence of a reduction in the number of bouts (exploratory events). Furthermore, we show an increase in bout exploration time and a decrease in bout instantaneous speed for colonies inhabiting better homes. The effect of treatment on bout effort is very small; however, we suggest that the organization of work performed within nest searching is achieved both by a process of self-selection of the most hard-working ants and individual effort adjustment. PMID:26909180

  19. Exploration versus exploitation in polydomous ant colonies.

    PubMed

    Cook, Zoe; Franks, Daniel W; Robinson, Elva J H

    2013-04-21

    In socially foraging species resource information can be shared between individuals, increasing foraging success. In ant colonies, nestmate recruitment allows high exploitation rates at known resources however, to maximise foraging efficiency this must be balanced with searching for new resources. Many ant species form colonies inhabiting two or more spatially separated but socially connected nests: this type of organisation is known as polydomy. Polydomous colonies may benefit from increased foraging efficiency by carrying out dispersed-central place foraging. However, decentralisation of the colony may affect recruitment success by limiting interaction between ants based in separate nests. We use an agent-based model which compares the foraging success of monodomous and polydomous colonies in different food environments, incorporating recruitment through pheromone trails and group foraging. In contrast to previous results we show that polydomy is beneficial in some but not all cases. Polydomous colonies discover resources at a higher rate, making them more successful when food is highly dispersed, but their relative success can be lowered by limitations on recruitment success. Monodomous colonies can have higher foraging efficiency than polydomous colonies by exploiting food more rapidly. The results show the importance of interactions between recruitment strategy, colony size, and colony organisation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Conceptual design of a lunar colony

    NASA Technical Reports Server (NTRS)

    Dalton, C. (Editor); Hohmann, E. (Editor)

    1972-01-01

    A systems engineering study is presented for a proposed lunar colony. The lunar colony was to grow from an existent, 12-man, earth-dependent lunar surface base and was to utilize lunar resources, becoming as earth-independent as possible. An in-depth treatment of some of the aspects of the lunar colony was given. We have found that the use of lunar resources is feasible for oxygen production (both for breathing and for space tug fuel), food production, and building materials. A program is outlined for recycling waste materials developed at the colony as well as a full program for growth and research activity of the colony to a level of 180 colonists. Recommendations for the lunar colony are given.

  1. Hydrodynamics of bacterial colonies: Phase diagrams

    NASA Astrophysics Data System (ADS)

    Lega, J.; Passot, T.

    2004-09-01

    We present numerical simulations of a recent hydrodynamic model describing the growth of bacterial colonies on agar plates. We show that this model is able to qualitatively reproduce experimentally observed phase diagrams, which relate a colony shape to the initial quantity of nutrients on the plate and the initial wetness of the agar. We also discuss the principal features resulting from the interplay between hydrodynamic motions and colony growth, as described by our model.

  2. THE COLONY MORPHOLOGY OF TUBERCLE BACILLI

    PubMed Central

    Smithburn, Kenneth C.

    1936-01-01

    The colony topography of tubercle bacilli is significantly affected by altering the pH of the culture medium on which the organisms are grown. Under the conditions of these experiments, avian tubercle bacilli produce two variants, rough and smooth. The former are most numerous on the most acid medium used (pH 6.0); the smooth colonies are obtained over a broad range of pH. Three colonial variants of bovine and human tubercle bacilli are described. Both mammalian types produce greater numbers of rough colonies at pH 6.0. The bovine type strains produce greatest numbers of smooth colonies in the pH range 6.4 to 6.8, and intermediate colonies on alkaline medium. The human type strains produce greatest numbers of smooth colonies at pH 6.4 and large numbers of intermediate colonies at pH 6.8 and pH 7.2. Included among the avian and bovine strains studied are organisms of widely varying pathogenic properties. Virulent and attenuated strains of a given type produce similar colonial variants under similar environmental conditions. PMID:19870462

  3. Bacterial colony counting by Convolutional Neural Networks.

    PubMed

    Ferrari, Alessandro; Lombardi, Stefano; Signoroni, Alberto

    2015-01-01

    Counting bacterial colonies on microbiological culture plates is a time-consuming, error-prone, nevertheless fundamental task in microbiology. Computer vision based approaches can increase the efficiency and the reliability of the process, but accurate counting is challenging, due to the high degree of variability of agglomerated colonies. In this paper, we propose a solution which adopts Convolutional Neural Networks (CNN) for counting the number of colonies contained in confluent agglomerates, that scored an overall accuracy of the 92.8% on a large challenging dataset. The proposed CNN-based technique for estimating the cardinality of colony aggregates outperforms traditional image processing approaches, becoming a promising approach to many related applications.

  4. Swarming dynamics in bacterial colonies

    NASA Astrophysics Data System (ADS)

    Zhang, H. P.; Be'er, Avraham; Smith, Rachel S.; Florin, E.-L.; Swinney, Harry L.

    2009-08-01

    We determine and relate the characteristic velocity, length, and time scales for bacterial motion in swarming colonies of Paenibacillus dendritiformis growing on semi-solid agar substrates. The bacteria swim within a thin fluid layer, and they form long-lived jets and vortices. These coherent structures lead to anisotropy in velocity spatial correlations and to a two-step relaxation in velocity temporal correlations. The mean squared displacement of passive tracers exhibits a short-time regime with nearly ballistic transport and a diffusive long-time regime. We find that various definitions of the correlation length all lead to length scales that are, surprisingly, essentially independent of the mean bacterial speed, while the correlation time is linearly proportional to the ratio of the correlation length to the mean speed.

  5. Predictive markers of honey bee colony collapse

    USDA-ARS?s Scientific Manuscript database

    Managed honey bee colonies are currently affected by abrupt depopulation during winter and many factors are suspected to be involved, either alone or in combination. Pathogens are considered as principal actors, contributing to weaken colony health and leaving room for secondary infections. In parti...

  6. Colonial America: A Course of Study.

    ERIC Educational Resources Information Center

    Bennett, Sondra; Stephens, Mark

    This illustrated unit of study can be incorporated into regular social studies courses in elementary classrooms. The unit focuses on life in the 13 original colonies from the settlement period to the Revolutionary War. Activities are provided to help students learn the names and locations of the colonies. A highlight of the unit is a study of the…

  7. Post-Colonialism Perspectives on Educational Competition

    ERIC Educational Resources Information Center

    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…

  8. Pathogen webs in collapsing honey bee colonies

    USDA-ARS?s Scientific Manuscript database

    Recent losses in honey bee colonies are unusual in their severity, geographical distribution, and, in some cases, failure to present recognized symptoms of known disease. Domesticated honey bees face numerous pests and pathogens, tempting hypotheses that colony collapses arise from exposure to new o...

  9. Colonialism in Modern America: The Appalachian Case.

    ERIC Educational Resources Information Center

    Lewis, Helen Matthews, Ed.; And Others

    The essays in this book illustrate a conceptual model for analyzing the social and economic problems of the Appalachian region. The model is variously called Colonialism, Internal Colonialism, Exploitation, or External Oppression. It highlights the process through which dominant outside industrial interests establish control, exploit the region,…

  10. Colonial America: A Course of Study.

    ERIC Educational Resources Information Center

    Bennett, Sondra; Stephens, Mark

    This illustrated unit of study can be incorporated into regular social studies courses in elementary classrooms. The unit focuses on life in the 13 original colonies from the settlement period to the Revolutionary War. Activities are provided to help students learn the names and locations of the colonies. A highlight of the unit is a study of the…

  11. Education in Colonial Africa: The German Experience

    ERIC Educational Resources Information Center

    vanderPloeg, Arie J.

    1977-01-01

    Examines the introduction and growth of state-supported schools in two German colonies in Africa, Kamerun and Deutsch Ostafrika, describes African reaction to and utilization of them, assesses, from the colonial perspective, why such schools were introduced and what they were intended to accomplish, and examines the reasons for their differential…

  12. Colonial American Literature: A Guide to Resources.

    ERIC Educational Resources Information Center

    Van Noate, Judith, Comp.

    This handout is a guide to library resources in the J. Murrey Atkins Library at the University of North Carolina-Charlotte for the study of colonial American literature. The guide is intended to help readers find sources of criticism on colonial and revolutionary literature. It explains important reference sources in the Atkins library reference…

  13. Genetic Analysis of Termite Colonies in Wisconsin

    Treesearch

    R.A. Arango; D.A. Marschalek; F. Green III; K.F. Raffa; M.E. Berres

    2015-01-01

    The objective of this study was to document current areas of subterranean termite activity in Wisconsin and to evaluate genetic characteristics of these northern, peripheral colonies. Here, amplified fragment-length polymorphism was used to characterize levels of inbreeding, expected heterozygosity, and percent polymorphism within colonies as well as genetic structure...

  14. Energy, Colonialism, and the American West.

    ERIC Educational Resources Information Center

    Warren, Eugene H., Jr.

    1983-01-01

    Energy development has led many people concerned with the American West to consider it a powerless colony of outside interests. The characteristics of colonies, particularly external control by energy companies and the federal government, and the applicability of these characteristics to the West are discussed. (IS)

  15. Post-Colonialism Perspectives on Educational Competition

    ERIC Educational Resources Information Center

    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…

  16. Colony Collapse Disorder: A descriptive studey

    USDA-ARS?s Scientific Manuscript database

    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 ...

  17. [Notes about other epidemics in Colonial Chile].

    PubMed

    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.

  18. Education in Colonial Africa: The German Experience

    ERIC Educational Resources Information Center

    vanderPloeg, Arie J.

    1977-01-01

    Examines the introduction and growth of state-supported schools in two German colonies in Africa, Kamerun and Deutsch Ostafrika, describes African reaction to and utilization of them, assesses, from the colonial perspective, why such schools were introduced and what they were intended to accomplish, and examines the reasons for their differential…

  19. Deadly competition between sibling bacterial colonies

    PubMed Central

    Be'er, Avraham; Zhang, H. P.; Florin, E.-L.; Payne, Shelley M.; Ben-Jacob, Eshel; Swinney, Harry L.

    2009-01-01

    Bacteria can secrete a wide array of antibacterial compounds when competing with other bacteria for the same resources. Some of these compounds, such as bacteriocins, can affect bacteria of similar or closely related strains. In some cases, these secretions have been found to kill sibling cells that belong to the same colony. Here, we present experimental observations of competition between 2 sibling colonies of Paenibacillus dendritiformis grown on a low-nutrient agar gel. We find that neighboring colonies (growing from droplet inoculation) mutually inhibit growth through secretions that become lethal if the level exceeds a well-defined threshold. In contrast, within a single colony developing from a droplet inoculation, no growth inhibition is observed. However, growth inhibition and cell death are observed if material extracted from the agar between 2 growing colonies is introduced outside a growing single colony. To interpret the observations, we devised a simple mathematical model for the secretion of an antibacterial compound. Simulations of this model illustrate how secretions from neighboring colonies can be deadly, whereas secretions from a single colony growing from a droplet are not. PMID:19129489

  20. Genetic diversity in honey bee colonies enhances productivity and fitness.

    PubMed

    Mattila, Heather R; Seeley, Thomas D

    2007-07-20

    Honey bee queens mate with many males, creating numerous patrilines within colonies that are genetically distinct. The effects of genetic diversity on colony productivity and long-term fitness are unknown. We show that swarms from genetically diverse colonies (15 patrilines per colony) founded new colonies faster than swarms from genetically uniform colonies (1 patriline per colony). Accumulated differences in foraging rates, food storage, and population growth led to impressive boosts in the fitness (i.e., drone production and winter survival) of genetically diverse colonies. These results further our understanding of the origins of polyandry in honey bees and its benefits for colony performance.

  1. Hegemony and Accommodation in the History Curriculum in Colonial Botswana

    ERIC Educational Resources Information Center

    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.…

  2. Predictive markers of honey bee colony collapse.

    PubMed

    Dainat, Benjamin; Evans, Jay D; Chen, Yan Ping; Gauthier, Laurent; Neumann, Peter

    2012-01-01

    Across the Northern hemisphere, managed honey bee colonies, Apis mellifera, are currently affected by abrupt depopulation during winter and many factors are suspected to be involved, either alone or in combination. Parasites and pathogens are considered as principal actors, in particular the ectoparasitic mite Varroa destructor, associated viruses and the microsporidian Nosema ceranae. Here we used long term monitoring of colonies and screening for eleven disease agents and genes involved in bee immunity and physiology to identify predictive markers of honeybee colony losses during winter. The data show that DWV, Nosema ceranae, Varroa destructor and Vitellogenin can be predictive markers for winter colony losses, but their predictive power strongly depends on the season. In particular, the data support that V. destructor is a key player for losses, arguably in line with its specific impact on the health of individual bees and colonies.

  3. Formation and dissolution of bacterial colonies

    NASA Astrophysics Data System (ADS)

    Weber, Christoph A.; Lin, Yen Ting; Biais, Nicolas; Zaburdaev, Vasily

    2015-09-01

    Many organisms form colonies for a transient period of time to withstand environmental pressure. Bacterial biofilms are a prototypical example of such behavior. Despite significant interest across disciplines, physical mechanisms governing the formation and dissolution of bacterial colonies are still poorly understood. Starting from a kinetic description of motile and interacting cells we derive a hydrodynamic equation for their density on a surface, where most of the kinetic coefficients are estimated from experimental data for N. gonorrhoeae bacteria. We use it to describe the formation of multiple colonies with sizes consistent with experimental observations. Finally, we show how the changes in the cell-to-cell interactions lead to the dissolution of the bacterial colonies. The successful application of kinetic theory to a complex far from equilibrium system such as formation and dissolution of living bacterial colonies potentially paves the way for the physical quantification of the initial stages of biofilm formation.

  4. Formation and dissolution of bacterial colonies.

    PubMed

    Weber, Christoph A; Lin, Yen Ting; Biais, Nicolas; Zaburdaev, Vasily

    2015-09-01

    Many organisms form colonies for a transient period of time to withstand environmental pressure. Bacterial biofilms are a prototypical example of such behavior. Despite significant interest across disciplines, physical mechanisms governing the formation and dissolution of bacterial colonies are still poorly understood. Starting from a kinetic description of motile and interacting cells we derive a hydrodynamic equation for their density on a surface, where most of the kinetic coefficients are estimated from experimental data for N. gonorrhoeae bacteria. We use it to describe the formation of multiple colonies with sizes consistent with experimental observations. Finally, we show how the changes in the cell-to-cell interactions lead to the dissolution of the bacterial colonies. The successful application of kinetic theory to a complex far from equilibrium system such as formation and dissolution of living bacterial colonies potentially paves the way for the physical quantification of the initial stages of biofilm formation.

  5. Hydrodynamics of bacterial colonies: A model

    NASA Astrophysics Data System (ADS)

    Lega, J.; Passot, T.

    2003-03-01

    We propose a hydrodynamic model for the evolution of bacterial colonies growing on soft agar plates. This model consists of reaction-diffusion equations for the concentrations of nutrients, water, and bacteria, coupled to a single hydrodynamic equation for the velocity field of the bacteria-water mixture. It captures the dynamics inside the colony as well as on its boundary and allows us to identify a mechanism for collective motion towards fresh nutrients, which, in its modeling aspects, is similar to classical chemotaxis. As shown in numerical simulations, our model reproduces both usual colony shapes and typical hydrodynamic motions, such as the whirls and jets recently observed in wet colonies of Bacillus subtilis. The approach presented here could be extended to different experimental situations and provides a general framework for the use of advection-reaction-diffusion equations in modeling bacterial colonies.

  6. Predictive Markers of Honey Bee Colony Collapse

    PubMed Central

    Dainat, Benjamin; Evans, Jay D.; Chen, Yan Ping; Gauthier, Laurent; Neumann, Peter

    2012-01-01

    Across the Northern hemisphere, managed honey bee colonies, Apis mellifera, are currently affected by abrupt depopulation during winter and many factors are suspected to be involved, either alone or in combination. Parasites and pathogens are considered as principal actors, in particular the ectoparasitic mite Varroa destructor, associated viruses and the microsporidian Nosema ceranae. Here we used long term monitoring of colonies and screening for eleven disease agents and genes involved in bee immunity and physiology to identify predictive markers of honeybee colony losses during winter. The data show that DWV, Nosema ceranae, Varroa destructor and Vitellogenin can be predictive markers for winter colony losses, but their predictive power strongly depends on the season. In particular, the data support that V. destructor is a key player for losses, arguably in line with its specific impact on the health of individual bees and colonies. PMID:22384162

  7. Form and metabolic scaling in colonial animals.

    PubMed

    Hartikainen, Hanna; Humphries, Stuart; Okamura, Beth

    2014-03-01

    Benthic colonial organisms exhibit a wide variation in size and shape and provide excellent model systems for testing the predictions of models that describe the scaling of metabolic rate with organism size. We tested the hypothesis that colony form will influence metabolic scaling and its derivatives by characterising metabolic and propagule production rates in three species of freshwater bryozoans that vary in morphology and module organisation and which demonstrate two- and three-dimensional growth forms. The results were evaluated with respect to predictions from two models for metabolic scaling. Isometric metabolic scaling in two-dimensional colonies supported predictions of a model based on dynamic energy budget theory (DEB) and not those of a model based on fractally branching supply networks. This metabolic isometry appears to be achieved by equivalent energy budgets of edge and central modules, in one species (Cristatella mucedo) via linear growth and in a second species (Lophopus crystallinus) by colony fission. Allometric scaling characterised colonies of a three-dimensional species (Fredericella sultana), also providing support for the DEB model. Isometric scaling of propagule production rates for C. mucedo and F. sultana suggests that the number of propagules produced in colonies increases in direct proportion with the number of modules within colonies. Feeding currents generated by bryozoans function in both food capture and respiration, thus linking metabolic scaling with dynamics of self-shading and resource capture. Metabolic rates fundamentally dictate organismal performance (e.g. growth, reproduction) and, as we show here, are linked with colony form. Metabolic profiles and associated variation in colony form should therefore influence the outcome of biotic interactions in habitats dominated by colonial animals and may drive patterns of macroevolution.

  8. Growth of bacteria in 3-d colonies

    PubMed Central

    Mugler, Andrew; Kim, Justin

    2017-01-01

    The dynamics of growth of bacterial populations has been extensively studied for planktonic cells in well-agitated liquid culture, in which all cells have equal access to nutrients. In the real world, bacteria are more likely to live in physically structured habitats as colonies, within which individual cells vary in their access to nutrients. The dynamics of bacterial growth in such conditions is poorly understood, and, unlike that for liquid culture, there is not a standard broadly used mathematical model for bacterial populations growing in colonies in three dimensions (3-d). By extending the classic Monod model of resource-limited population growth to allow for spatial heterogeneity in the bacterial access to nutrients, we develop a 3-d model of colonies, in which bacteria consume diffusing nutrients in their vicinity. By following the changes in density of E. coli in liquid and embedded in glucose-limited soft agar, we evaluate the fit of this model to experimental data. The model accounts for the experimentally observed presence of a sub-exponential, diffusion-limited growth regime in colonies, which is absent in liquid cultures. The model predicts and our experiments confirm that, as a consequence of inter-colony competition for the diffusing nutrients and of cell death, there is a non-monotonic relationship between total number of colonies within the habitat and the total number of individual cells in all of these colonies. This combined theoretical-experimental study reveals that, within 3-d colonies, E. coli cells are loosely packed, and colonies produce about 2.5 times as many cells as the liquid culture from the same amount of nutrients. We verify that this is because cells in liquid culture are larger than in colonies. Our model provides a baseline description of bacterial growth in 3-d, deviations from which can be used to identify phenotypic heterogeneities and inter-cellular interactions that further contribute to the structure of bacterial

  9. Public health developments in colonial Malaya: colonialism and the politics of prevention.

    PubMed Central

    Manderson, L

    1999-01-01

    In both African and Asian colonies until the late 19th century, colonial medicine operated pragmatically to meet the medical needs first of colonial officers and troops, immigrant settlers, and laborers responsible for economic development, then of indigenous populations when their ill health threatened the well-being of the expatriate population. Since the turn of the century, however, the consequences of colonial expansion and development for indigenous people's health had become increasingly apparent, and disease control and public health programs were expanded in this light. These programs increased government surveillance of populations at both community and household levels. As a consequence, colonial states extended institutional oversight and induced dependency through public health measures. Drawing on my own work on colonial Malaya, I illustrate developments in public health and their links to the moral logic of colonialism and its complementarity to the political economy. PMID:9987478

  10. Public health developments in colonial Malaya: colonialism and the politics of prevention.

    PubMed

    Manderson, L

    1999-01-01

    In both African and Asian colonies until the late 19th century, colonial medicine operated pragmatically to meet the medical needs first of colonial officers and troops, immigrant settlers, and laborers responsible for economic development, then of indigenous populations when their ill health threatened the well-being of the expatriate population. Since the turn of the century, however, the consequences of colonial expansion and development for indigenous people's health had become increasingly apparent, and disease control and public health programs were expanded in this light. These programs increased government surveillance of populations at both community and household levels. As a consequence, colonial states extended institutional oversight and induced dependency through public health measures. Drawing on my own work on colonial Malaya, I illustrate developments in public health and their links to the moral logic of colonialism and its complementarity to the political economy.

  11. Measuring activity in ant colonies

    NASA Astrophysics Data System (ADS)

    Noda, C.; Fernández, J.; Pérez-Penichet, C.; Altshuler, E.

    2006-12-01

    Ants, as paradigm of social insects, have become a recurrent example of efficient problem solvers via self-organization. In spite of the simple behavior of each individual, the colony as a whole displays "swarm intelligence:" the organization of ant trails for foraging is a typical output of it. But conventional techniques of observation can hardly record the amount of data needed to get a detailed understanding of self-organization of ant swarms in the wild. Here we are presenting a measurement system intended to monitor ant activity in the field comprising massive data acquisition and high sensitivity. A central role is played by an infrared sensor devised specifically to monitor relevant parameters to the activity of ants through the exits of the nest, although other sensors detecting temperature and luminosity are added to the system. We study the characteristics of the activity sensor and its performance in the field. Finally, we present massive data measured at one exit of a nest of Atta insularis, an ant endemic to Cuba, to illustrate the potential of our system.

  12. Swarming dynamics in bacterial colonies

    NASA Astrophysics Data System (ADS)

    Zhang, Hepeng; Be'Er, Avraham; Smith, Rachel; Florin, E.-L.; Swinney, Harry L.

    2009-11-01

    Swarming is a widespread phenomenon observed in both biological and non-biological systems. Large mammal herds, fish schools, and bird flocks are among the most spectacular examples. Many theoretical and numerical efforts have been made to unveil the general principles of the phenomenon, but systematic experimental studies have been very limited. We determine the characteristic velocity, length, and time scales for bacterial motion in swarming colonies of Paenibacillus dendritiformis growing on semi-solid agar substrates. The bacteria swim within a thin fluid layer, and they form long-lived jets and vortices. These coherent structures lead to anisotropy in velocity spatial correlations and to a two-step relaxation in velocity temporal correlations. The mean squared displacement of passive tracers exhibits a short-time regime with nearly ballistic transport and a diffusive long-time regime. We find that various definitions of the correlation length all lead to length scales that are, surprisingly, essentially independent of the mean bacterial speed, while the correlation time is linearly proportional to the ratio of the correlation length to the mean speed.

  13. Colony Foundation in an Oceanic Seabird

    PubMed Central

    Munilla, Ignacio; Genovart, Meritxell; Paiva, Vitor H.; Velando, Alberto

    2016-01-01

    Seabirds are colonial vertebrates that despite their great potential for long-range dispersal and colonization are reluctant to establish in novel locations, often recruiting close to their natal colony. The foundation of colonies is therefore a rare event in most seabird species and little is known about the colonization process in this group. The Cory’s shearwater (Calonectris diomedea) is a pelagic seabird that has recently established three new colonies in Galicia (NE Atlantic) thus expanding its distribution range 500 km northwards. This study aimed to describe the establishment and early progress of the new Galician populations and to determine the genetic and morphometric characteristics of the individuals participating in these foundation events. Using 10 microsatellite loci, we tested the predictions supported by different seabird colonization models. Possibly three groups of non-breeders, adding up to around 200 birds, started visiting the Galician colonies in the mid 2000’s and some of them eventually laid eggs and reproduced, thus establishing new breeding colonies. The Galician populations showed a high genetic diversity and a frequency of private alleles similar to or even higher than some of the large historical populations. Most individuals were assigned to several Atlantic populations and a few (if any) to Mediterranean colonies. Our study suggests that a large and admixed population is settling in Galicia, in agreement with predictions from island metapopulation models of colonization. Multiple source colonies imply that some birds colonizing Galicia were dispersing from very distant colonies (> 1500 km). Long-distance colonizations undertaken by relatively large and admixed groups of colonizers can help to explain the low levels of genetic structure over vast areas that are characteristic of most oceanic seabird species. PMID:26909694

  14. The Lost Colony and Jamestown droughts.

    PubMed

    Stahle, D W; Cleaveland, M K; Blanton, D B; Therrell, M D; Gay, D A

    1998-04-24

    Tree-ring data from Virginia indicate that the Lost Colony of Roanoke Island disappeared during the most extreme drought in 800 years (1587-1589) and that the alarming mortality and the near abandonment of Jamestown Colony occurred during the driest 7-year episode in 770 years (1606-1612). These extraordinary droughts can now be implicated in the fate of the Lost Colony and in the appalling death rate during the early occupations at Jamestown, the first permanent English settlement in America.

  15. Epidemiology of coronary artery bypass grafting at the Hospital Beneficência Portuguesa, São Paulo

    PubMed Central

    de Sousa, Alexandre Gonçalves; Fichino, Maria Zenaide Soares; da Silva, Gilmara Silveira; Bastos, Flávia Cortez Colosimo; Piotto, Raquel Ferrari

    2015-01-01

    Introduction The knowledge of the prevalence of risk factors and comorbidities, as well as the evolution and complications in patients undergoing coronary artery bypass graft allows comparison between institutions and evidence of changes in the profile of patients and postoperative evolution over time. Objective To profile (risk factors and comorbidities) and clinical outcome (complications) in patients undergoing coronary artery bypass graft in a national institution of great surgical volume. Methods A retrospective cohort study of patients undergoing coronary artery bypass graft in the hospital Beneficência Portuguesa de São Paulo, from July 2009 to July 2010. Results We included 3,010 patients, mean age of 62.2 years and 69.9% male. 83.8% of patients were hypertensive, 36.6% diabetic, 44.5% had dyslipidemia, 15.3% were smokers, 65.7% were overweight/obese, 29.3% had a family history of coronary heart disease. The expected mortality calculated by logistic EuroSCORE was 2.7%. The isolated CABG occurred in 89.3% and 11.9% surgery was performed without cardiopulmonary bypass. The most common complication was cardiac arrhythmia (18.7%), especially acute atrial fibrillation (14.3%). Pneumonia occurred in 6.2% of patients, acute renal failure in 4.4%, mediastinites in 2.1%, stroke in 1.8% and AMI in 1.2%. The in-hospital mortality was 5.4% and in isolated coronary artery bypass graft was 3.5%. The average hospital stay was 11 days with a median of eight days (3-244 days). Conclusion The profile of patients undergoing coronary artery bypass graft surgery in this study is similar to other published studies. PMID:25859865

  16. Application of continuous monitoring of honeybee colonies

    USDA-ARS?s Scientific Manuscript database

    Monitoring physical variables associated with honey bee colonies, including weight, temperature, humidity, respiratory gases, vibration, acoustics and forager traffic, in a continuous manner is becoming feasible for most researchers as the cost and size of electronic sensors and dataloggers decrease...

  17. Optical image acquisition system for colony analysis

    NASA Astrophysics Data System (ADS)

    Wang, Weixing; Jin, Wenbiao

    2006-02-01

    For counting of both colonies and plaques, there is a large number of applications including food, dairy, beverages, hygiene, environmental monitoring, water, toxicology, sterility testing, AMES testing, pharmaceuticals, paints, sterile fluids and fungal contamination. Recently, many researchers and developers have made efforts for this kind of systems. By investigation, some existing systems have some problems since they belong to a new technology product. One of the main problems is image acquisition. In order to acquire colony images with good quality, an illumination box was constructed as: the box includes front lightning and back lightning, which can be selected by users based on properties of colony dishes. With the illumination box, lightning can be uniform; colony dish can be put in the same place every time, which make image processing easy. A digital camera in the top of the box connected to a PC computer with a USB cable, all the camera functions are controlled by the computer.

  18. Glendale Colony and Harvey Farms NPDES Permit

    EPA Pesticide Factsheets

    Under NPDES permit MT-0031819, Glendale Colony, Inc., and Harvey Farms, Inc. are authorized to discharge and must operate their facilities in accordance with provisions set forth herein.Indian Country on the Blackfeet Reserva

  19. Feeding, Swimming and Navigation of Colonial Microorganisms

    NASA Astrophysics Data System (ADS)

    Kirkegaard, Julius; Bouillant, Ambre; Marron, Alan; Leptos, Kyriacos; Goldstein, Raymond

    2016-11-01

    Animals are multicellular in nature, but evolved from unicellular organisms. In the closest relatives of animals, the choanoflagellates, the unicellular species Salpincgoeca rosetta has the ability to form colonies, resembling true multicellularity. In this work we use a combination of experiments, theory, and simulations to understand the physical differences that arise from feeding, swimming and navigating as colonies instead of as single cells. We show that the feeding efficiency decreases with colony size for distinct reasons in the small and large Péclet number limits, and we find that swimming as a colony changes the conventional active random walks of microorganism to stochastic helices, but that this does not hinder effective navigation towards chemoattractants.

  20. Identification of a Colonial Chordate Histocompatibility Gene

    PubMed Central

    Voskoboynik, Ayelet; Newman, Aaron M.; Corey, Daniel M.; Sahoo, Debashis; Pushkarev, Dmitry; Neff, Norma F.; Passarelli, Benedetto; Koh, Winston; Ishizuka, Katherine J.; Palmeri, Karla J.; Dimov, Ivan K.; Keasar, Chen; Fan, H. Christina; Mantalas, Gary L.; Sinha, Rahul; Penland, Lolita; Quake, Stephen R.; Weissman, Irving L.

    2013-01-01

    Histocompatibility is the basis by which multicellular organisms of the same species distinguish self from non-self. Relatively little is known about the mechanisms underlying histocompatibility reactions in lower organisms. Botryllus schlosseri is a colonial urochordate, a sister group of vertebrates, that exhibits a genetically determined natural transplantation reaction, whereby self-recognition between colonies leads to formation of parabionts with a common vasculature, whereas rejection occurs between incompatible colonies. Using genetically defined lines, whole-transcriptome sequencing, and genomics, we identified a single gene that encodes self/non-self and determines “graft” outcomes in this organism. This gene is significantly upregulated in colonies poised to undergo fusion or rejection, is highly expressed in the vasculature, and is functionally linked to histocompatibility outcomes. These findings establish a platform for advancing the science of allorecognition. PMID:23888037

  1. Pathogen Webs in Collapsing Honey Bee Colonies

    PubMed Central

    Cornman, R. Scott; Tarpy, David R.; Chen, Yanping; Jeffreys, Lacey; Lopez, Dawn; Pettis, Jeffery S.; vanEngelsdorp, Dennis; Evans, Jay D.

    2012-01-01

    Recent losses in honey bee colonies are unusual in their severity, geographical distribution, and, in some cases, failure to present recognized characteristics of known disease. Domesticated honey bees face numerous pests and pathogens, tempting hypotheses that colony collapses arise from exposure to new or resurgent pathogens. Here we explore the incidence and abundance of currently known honey bee pathogens in colonies suffering from Colony Collapse Disorder (CCD), otherwise weak colonies, and strong colonies from across the United States. Although pathogen identities differed between the eastern and western United States, there was a greater incidence and abundance of pathogens in CCD colonies. Pathogen loads were highly covariant in CCD but not control hives, suggesting that CCD colonies rapidly become susceptible to a diverse set of pathogens, or that co-infections can act synergistically to produce the rapid depletion of workers that characterizes the disorder. We also tested workers from a CCD-free apiary to confirm that significant positive correlations among pathogen loads can develop at the level of individual bees and not merely as a secondary effect of CCD. This observation and other recent data highlight pathogen interactions as important components of bee disease. Finally, we used deep RNA sequencing to further characterize microbial diversity in CCD and non-CCD hives. We identified novel strains of the recently described Lake Sinai viruses (LSV) and found evidence of a shift in gut bacterial composition that may be a biomarker of CCD. The results are discussed with respect to host-parasite interactions and other environmental stressors of honey bees. PMID:22927991

  2. Pathogen webs in collapsing honey bee colonies.

    PubMed

    Cornman, R Scott; Tarpy, David R; Chen, Yanping; Jeffreys, Lacey; Lopez, Dawn; Pettis, Jeffery S; vanEngelsdorp, Dennis; Evans, Jay D

    2012-01-01

    Recent losses in honey bee colonies are unusual in their severity, geographical distribution, and, in some cases, failure to present recognized characteristics of known disease. Domesticated honey bees face numerous pests and pathogens, tempting hypotheses that colony collapses arise from exposure to new or resurgent pathogens. Here we explore the incidence and abundance of currently known honey bee pathogens in colonies suffering from Colony Collapse Disorder (CCD), otherwise weak colonies, and strong colonies from across the United States. Although pathogen identities differed between the eastern and western United States, there was a greater incidence and abundance of pathogens in CCD colonies. Pathogen loads were highly covariant in CCD but not control hives, suggesting that CCD colonies rapidly become susceptible to a diverse set of pathogens, or that co-infections can act synergistically to produce the rapid depletion of workers that characterizes the disorder. We also tested workers from a CCD-free apiary to confirm that significant positive correlations among pathogen loads can develop at the level of individual bees and not merely as a secondary effect of CCD. This observation and other recent data highlight pathogen interactions as important components of bee disease. Finally, we used deep RNA sequencing to further characterize microbial diversity in CCD and non-CCD hives. We identified novel strains of the recently described Lake Sinai viruses (LSV) and found evidence of a shift in gut bacterial composition that may be a biomarker of CCD. The results are discussed with respect to host-parasite interactions and other environmental stressors of honey bees.

  3. Polydomy enhances foraging performance in ant colonies.

    PubMed

    Stroeymeyt, N; Joye, P; Keller, L

    2017-04-26

    Collective foraging confers benefits in terms of reduced predation risk and access to social information, but it heightens local competition when resources are limited. In social insects, resource limitation has been suggested as a possible cause for the typical decrease in per capita productivity observed with increasing colony size, a phenomenon known as Michener's paradox. Polydomy (distribution of a colony's brood and workers across multiple nests) is believed to help circumvent this paradox through its positive effect on foraging efficiency, but there is still little supporting evidence for this hypothesis. Here, we show experimentally that polydomy enhances the foraging performance of food-deprived Temnothorax nylanderi ant colonies via several mechanisms. First, polydomy influences task allocation within colonies, resulting in faster retrieval of protein resources. Second, communication between sister nests reduces search times for far away resources. Third, colonies move queens, brood and workers across available nest sites in response to spatial heterogeneities in protein and carbohydrate resources. This suggests that polydomy represents a flexible mechanism for space occupancy, helping ant colonies adjust to the environment. © 2017 The Author(s).

  4. Periodic Pattern Formation of Bacterial Colonies

    NASA Astrophysics Data System (ADS)

    Itoh, Hiroto; Wakita, Jun-ichi; Matsuyama, Tohey; Matsushita, Mitsugu

    1999-04-01

    We have experimentally investigated pattern formation of colonies ofbacterial species Proteus mirabilis, which is famous forforming concentric-ring-like colonies.The colony grows cyclically with the interface repeating an advance anda stop alternately on a surface of a solid agar medium.We distinguish three phases (initial lag phase, the followingmigration and consolidation phases that appear alternately) for the colony growth.When we cut a colony just behind a migrating front shortly after the migrationstarted, the migration ended earlier and the following consolidationlasted longer.However, the following cycles were not influenced by the cut, i.e., thephases of the migration and consolidation were not affected.Global chemical signals governing the colony formation from thecenter were not found to exist.We also quantitatively checked phase entrainment by letting two coloniescollide with each other and found that it does not take place in macroscopic scales.All these experimental results suggest that the most important factorfor the migration is the cell population density.

  5. BIOLUMINESCENT BEHAVIOR IN RENILLA. I. COLONIAL RESPONSES.

    PubMed

    Buck, John

    1973-02-01

    1. Some details are given of the external morphology of the autozooids and siphonozooids and of their distribution in the colony. It is estimated that a minimum of over 6 meters of nerve net would be required to conduct excitation across an average-size colony during the passage of a wave of luminescence. 2. An account is given of the localization of luminescence in the two types of polyp and of their apparently differing behaviors in colonies collected in summer and winter. 3. In summer colonies the sharp luminous waves induced by electrical stimulation are entirely due to siphonozooids. Under strong stimulation the autozooid calices produce a long lasting glow. 4. Neuroeffector facilitation takes place uniformly throughout the colonial conduction system. Decay of facilitation requires 10-36 seconds, by different tests. There are indications that sensory adaptation in the (hypothetical) net can be local. 5. Local recording shows that the response cycle in small areas of the colony is much shorter, and its frequency response much higher, than indicated by integrative recordings of the wave response as a whole. 6. Individual siphonozooid clusters can flash repetitively in successive waves, fail to participate in every wave and vary in intensity from wave to wave. The increase in light intensity during successive facilitating waves seems due to increase in the activity of individual clusters, not to recruitment of additional clusters. There were indications of individual differences in threshold, adaptation and autoexcitation between clusters. 7. During strong repetitive electrical stimulation there may arise extra siphonozooid waves of augmented brightness, running in the same direction as the "normal" waves ( i.e., centrifugally from the electrode) or in the reverse direction. The colony may then enter an autoexcitatory state ("frenzy"), independent of external stimulation and often involving development of several excitation centers, in which waves of irregular

  6. Substrate Stiffness Affects Human Keratinocyte Colony Formation

    PubMed Central

    Zarkoob, Hoda; Bodduluri, Sandeep; Ponnaluri, Sailahari V.; Selby, John C.; Sander, Edward A.

    2015-01-01

    Restoration of epidermal organization and function in response to a variety of pathophysiological insults is critically dependent on coordinated keratinocyte migration, proliferation, and stratification during the process of wound healing. These processes are mediated by the reconfiguration of both cell-cell (desmosomes, adherens junctions) and cell-matrix (focal adhesions, hemidesmosomes) junctions and the cytoskeletal filament networks that they serve to interconnect. In this study, we investigated the role of substrate elasticity (stiffness) on keratinocyte colony formation in vitro during the process of nascent epithelial sheet formation as triggered by the calcium switch model of keratinocyte culture. Keratinocytes cultured on pepsin digested type I collagen coated soft (nominal E = 1.2 kPa) polyacrylamide gels embedded with fluorescent microspheres exhibited (i) smaller spread contact areas, (ii) increased migration velocities, and (iii) increased rates of colony formation with more cells per colony than did keratinocytes cultured on stiff (nominal E = 24 kPa) polyacrylamide gels. As assessed by tracking of embedded microsphere displacements, keratinocytes cultured on soft substrates generated large local substrate deformations that appeared to recruit adjacent keratinocytes into joining an evolving colony. Together with the observed differences in keratinocyte kinematics and substrate deformations, we developed two ad hoc analyses, termed distance rank (DR) and radius of cooperativity (RC), that help to objectively ascribe what we perceive as increasingly cooperative behavior of keratinocytes cultured on soft versus stiff gels during the process of colony formation. We hypothesize that the differences in keratinocyte colony formation observed in our experiments could be due to cell-cell mechanical signaling generated via local substrate deformations that appear to be correlated with the increased expression of β4 integrin within keratinocytes positioned

  7. Geometry and mechanics of growing bacterial colonies

    NASA Astrophysics Data System (ADS)

    You, Zhihong; Pearce, Daniel; Sengupta, Anupam; Giomi, Luca

    Bacterial colonies are abundant on living and non-living surfaces, and are known to mediate a broad range of processes in ecology, medicine and industry. Although extensively researched - from single cells up to the population levels - a comprehensive biophysical picture, highlighting the cell-to-colony dynamics, is still lacking. Here, using numerical and analytical models, we study the mechanics of self-organization leading to the colony morphology of cells growing on a substrate with free boundary. We consider hard rods to mimic the growth of rod-shaped non-motile cells, and show that the colony, as a whole, does not form an ordered nematic phase, nor does it result in a purely disordered (isotropic) phase. Instead, different sizes of domains, in which cells are highly aligned at specific orientations, are found. The distribution of the domain sizes follows an exponential relation - indicating the existence of a characteristic length scale that determines the domain size relative to that of the colony. A continuum theory, based on the hydrodynamics of liquid crystals, is built to account for these phenomena, and is applied to describe the buckling transition from a planar to three-dimensional (3D) colony. The theory supports preliminary experiments conducted with different strains of rod shaped bacterial cells, and reveals that the buckling transition can be regulated by varying the cell stiffness and aspect ratio. This work proposes that, in addition to biochemical pathways, the spatio-temporal organization in microbial colonies is significantly tuned by the biomechanical and geometric properties of the microbes in consideration.

  8. Automated counting of bacterial colony forming units on agar plates.

    PubMed

    Brugger, Silvio D; Baumberger, Christian; Jost, Marcel; Jenni, Werner; Brugger, Urs; Mühlemann, Kathrin

    2012-01-01

    Manual counting of bacterial colony forming units (CFUs) on agar plates is laborious and error-prone. We therefore implemented a colony counting system with a novel segmentation algorithm to discriminate bacterial colonies from blood and other agar plates.A colony counter hardware was designed and a novel segmentation algorithm was written in MATLAB. In brief, pre-processing with Top-Hat-filtering to obtain a uniform background was followed by the segmentation step, during which the colony images were extracted from the blood agar and individual colonies were separated. A Bayes classifier was then applied to count the final number of bacterial colonies as some of the colonies could still be concatenated to form larger groups. To assess accuracy and performance of the colony counter, we tested automated colony counting of different agar plates with known CFU numbers of S. pneumoniae, P. aeruginosa and M. catarrhalis and showed excellent performance.

  9. Automated Counting of Bacterial Colony Forming Units on Agar Plates

    PubMed Central

    Brugger, Silvio D.; Baumberger, Christian; Jost, Marcel; Jenni, Werner; Brugger, Urs; Mühlemann, Kathrin

    2012-01-01

    Manual counting of bacterial colony forming units (CFUs) on agar plates is laborious and error-prone. We therefore implemented a colony counting system with a novel segmentation algorithm to discriminate bacterial colonies from blood and other agar plates. A colony counter hardware was designed and a novel segmentation algorithm was written in MATLAB. In brief, pre-processing with Top-Hat-filtering to obtain a uniform background was followed by the segmentation step, during which the colony images were extracted from the blood agar and individual colonies were separated. A Bayes classifier was then applied to count the final number of bacterial colonies as some of the colonies could still be concatenated to form larger groups. To assess accuracy and performance of the colony counter, we tested automated colony counting of different agar plates with known CFU numbers of S. pneumoniae, P. aeruginosa and M. catarrhalis and showed excellent performance. PMID:22448267

  10. Establishment of a Salmonella-Free Guinea Pig Colony

    PubMed Central

    Pivnick, Hilliard; Stuart, Philip F.; Walcroft, M.

    1966-01-01

    Salmonellosis due to Salmonella typhimurium was enzootic in a guinea pig breeding colony for over 25 years. A Salmonella-free auxiliary colony was established by removing weanlings from the infected colony to a clean area, and preventing infection. Examination of agglutinin titers and necropsy specimens indicated that the auxiliary colony was still free from Salmonella 18 months after its establishment while 24% of the guinea pigs dying in the infected colony yielded Salmonella typhimurium. PMID:17649571

  11. Parasitism and phenotypic change in colonial hosts.

    PubMed

    Hartikainen, Hanna; Fontes, Inês; Okamura, Beth

    2013-09-01

    Changes in host phenotype are often attributed to manipulation that enables parasites to complete trophic transmission cycles. We characterized changes in host phenotype in a colonial host–endoparasite system that lacks trophic transmission (the freshwater bryozoan Fredericella sultana and myxozoan parasite Tetracapsuloides bryosalmonae). We show that parasitism exerts opposing phenotypic effects at the colony and module levels. Thus, overt infection (the development of infectious spores in the host body cavity) was linked to a reduction in colony size and growth rate, while colony modules exhibited a form of gigantism. Larger modules may support larger parasite sacs and increase metabolite availability to the parasite. Host metabolic rates were lower in overtly infected relative to uninfected hosts that were not investing in propagule production. This suggests a role for direct resource competition and active parasite manipulation (castration) in driving the expression of the infected phenotype. The malformed offspring (statoblasts) of infected colonies had greatly reduced hatching success. Coupled with the severe reduction in statoblast production this suggests that vertical transmission is rare in overtly infected modules. We show that although the parasite can occasionally infect statoblasts during overt infections, no infections were detected in the surviving mature offspring, suggesting that during overt infections, horizontal transmission incurs a trade-off with vertical transmission.

  12. Quantitative analysis of colony morphology in yeast.

    PubMed

    Ruusuvuori, Pekka; Lin, Jake; Scott, Adrian C; Tan, Zhihao; Sorsa, Saija; Kallio, Aleksi; Nykter, Matti; Yli-Harja, Olli; Shmulevich, Ilya; Dudley, Aimée M

    2014-01-01

    Microorganisms often form multicellular structures such as biofilms and structured colonies that can influence the organism's virulence, drug resistance, and adherence to medical devices. Phenotypic classification of these structures has traditionally relied on qualitative scoring systems that limit detailed phenotypic comparisons between strains. Automated imaging and quantitative analysis have the potential to improve the speed and accuracy of experiments designed to study the genetic and molecular networks underlying different morphological traits. For this reason, we have developed a platform that uses automated image analysis and pattern recognition to quantify phenotypic signatures of yeast colonies. Our strategy enables quantitative analysis of individual colonies, measured at a single time point or over a series of time-lapse images, as well as the classification of distinct colony shapes based on image-derived features. Phenotypic changes in colony morphology can be expressed as changes in feature space trajectories over time, thereby enabling the visualization and quantitative analysis of morphological development. To facilitate data exploration, results are plotted dynamically through an interactive Yeast Image Analysis web application (YIMAA; http://yimaa.cs.tut.fi) that integrates the raw and processed images across all time points, allowing exploration of the image-based features and principal components associated with morphological development.

  13. Colony Collapse Disorder: A Descriptive Study

    PubMed Central

    vanEngelsdorp, Dennis; Evans, Jay D.; Saegerman, Claude; Mullin, Chris; Haubruge, Eric; Nguyen, Bach Kim; Frazier, Maryann; Frazier, Jim; Cox-Foster, Diana; Chen, Yanping; Underwood, Robyn; Tarpy, David R.; Pettis, Jeffery S.

    2009-01-01

    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. PMID:19649264

  14. Colony collapse disorder: a descriptive study.

    PubMed

    Vanengelsdorp, Dennis; Evans, Jay D; Saegerman, Claude; Mullin, Chris; Haubruge, Eric; Nguyen, Bach Kim; Frazier, Maryann; Frazier, Jim; Cox-Foster, Diana; Chen, Yanping; Underwood, Robyn; Tarpy, David R; Pettis, Jeffery S

    2009-08-03

    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. 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. 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.

  15. Ant Colony Optimization Algorithm for Continuous Domains Based on Position Distribution Model of Ant Colony Foraging

    PubMed Central

    Liu, Liqiang; Dai, Yuntao

    2014-01-01

    Ant colony optimization algorithm for continuous domains is a major research direction for ant colony optimization algorithm. In this paper, we propose a distribution model of ant colony foraging, through analysis of the relationship between the position distribution and food source in the process of ant colony foraging. We design a continuous domain optimization algorithm based on the model and give the form of solution for the algorithm, the distribution model of pheromone, the update rules of ant colony position, and the processing method of constraint condition. Algorithm performance against a set of test trials was unconstrained optimization test functions and a set of optimization test functions, and test results of other algorithms are compared and analyzed to verify the correctness and effectiveness of the proposed algorithm. PMID:24955402

  16. Ant colony optimization algorithm for continuous domains based on position distribution model of ant colony foraging.

    PubMed

    Liu, Liqiang; Dai, Yuntao; Gao, Jinyu

    2014-01-01

    Ant colony optimization algorithm for continuous domains is a major research direction for ant colony optimization algorithm. In this paper, we propose a distribution model of ant colony foraging, through analysis of the relationship between the position distribution and food source in the process of ant colony foraging. We design a continuous domain optimization algorithm based on the model and give the form of solution for the algorithm, the distribution model of pheromone, the update rules of ant colony position, and the processing method of constraint condition. Algorithm performance against a set of test trials was unconstrained optimization test functions and a set of optimization test functions, and test results of other algorithms are compared and analyzed to verify the correctness and effectiveness of the proposed algorithm.

  17. Productivity, individual-level and colony-level flexibility, and organization of work as consequences of colony size

    PubMed Central

    Karsai, István; Wenzel, John W.

    1998-01-01

    In social insects, colony-level complexity may emerge from simple individual-level behaviors and interactions. Emergent global properties such as colony size, which can be viewed as a consequence of life history traits, may influence individual-level behaviors themselves. The effects of colony size on productivity, body size, behavioral flexibility, and colony organization are examined here by considering colony size as an independent variable. Large colony size commonly corresponds with complex colony-level performance, small body size, and lower per capita productivity. Analyzing the construction behavior of various wasp societies reveals that complexity of individual behavior is inversely related to colony size. Parallel processing by specialists in large colonies provides flexible and efficient colony-level functioning. On the other hand, individual behavioral flexibility of jack-of-all trades workers ensures success of the small and early societies. PMID:9671735

  18. Variations and heredity in bacterial colonies

    PubMed Central

    Čepl, Jaroslav; Blahůšková, Anna; Neubauer, Zdeněk; Markoš, Anton

    2016-01-01

    ABSTRACT Spontaneous variation in appearance was studied in bacterial colonies of Serratia marcescens F morphotype1: (i) A defined array of non-heritable phenotype variations does appear repeatedly; (ii) The presence of colonies of different bacterial species will narrow the variability toward the typical F appearance, as if such an added environmental factor curtailed the capacity of colony morphospace; (iii) Similarly the morphospace becomes reduced by random mutations leading to new, heritable morphotypes—at the same time opening a new array of variations typical for the mutant but not accessible directly from the original F morphospace. Results are discussed in context with biphasic model of early morphogenesis applicable to all multicellular bodies. PMID:28042382

  19. Energetic inequivalence in eusocial insect colonies

    PubMed Central

    DeLong, John P.

    2011-01-01

    The energetic equivalence rule states that population-level metabolic rate is independent of average body size. This rule has been both supported and refuted by allometric studies of abundance and individual metabolic rate, but no study, to my knowledge, has tested the rule with direct measurements of whole-population metabolic rate. Here, I find a positive scaling of whole-colony metabolic rate with body size for eusocial insects. Individual metabolic rates in these colonies scaled with body size more steeply than expected from laboratory studies on insects, while population size was independent of body size. Using consumer-resource models, I suggest that the colony-level metabolic rate scaling observed here may arise from a change in the scaling of individual metabolic rate resulting from a change in the body size dependence of mortality rates. PMID:21367781

  20. Early Developmental Program Shapes Colony Morphology in Bacteria

    PubMed Central

    Mamou, Gideon; Malli Mohan, Ganesh Babu; Rouvinski, Alex; Rosenberg, Alex; Ben-Yehuda, Sigal

    2016-01-01

    Summary 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. PMID:26904951

  1. Early Developmental Program Shapes Colony Morphology in Bacteria.

    PubMed

    Mamou, Gideon; Malli Mohan, Ganesh Babu; Rouvinski, Alex; Rosenberg, Alex; Ben-Yehuda, Sigal

    2016-03-01

    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.

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

    PubMed

    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.

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

    PubMed Central

    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. PMID:27583438

  4. Predicting Honeybee Colony Failure: Using the BEEHAVE Model to Simulate Colony Responses to Pesticides

    PubMed Central

    2015-01-01

    To simulate effects of pesticides on different honeybee (Apis mellifera L.) life stages, we used the BEEHAVE model to explore how increased mortalities of larvae, in-hive workers, and foragers, as well as reduced egg-laying rate, could impact colony dynamics over multiple years. Stresses were applied for 30 days, both as multiples of the modeled control mortality and as set percentage daily mortalities to assess the sensitivity of the modeled colony both to small fluctuations in mortality and periods of low to very high daily mortality. These stresses simulate stylized exposure of the different life stages to nectar and pollen contaminated with pesticide for 30 days. Increasing adult bee mortality had a much greater impact on colony survival than mortality of bee larvae or reduction in egg laying rate. Importantly, the seasonal timing of the imposed mortality affected the magnitude of the impact at colony level. In line with the LD50, we propose a new index of “lethal imposed stress”: the LIS50 which indicates the level of stress on individuals that results in 50% colony mortality. This (or any LISx) is a comparative index for exploring the effects of different stressors at colony level in model simulations. While colony failure is not an acceptable protection goal, this index could be used to inform the setting of future regulatory protection goals. PMID:26444386

  5. Predicting Honeybee Colony Failure: Using the BEEHAVE Model to Simulate Colony Responses to Pesticides.

    PubMed

    Rumkee, Jack C O; Becher, Matthias A; Thorbek, Pernille; Kennedy, Peter J; Osborne, Juliet L

    2015-11-03

    To simulate effects of pesticides on different honeybee (Apis mellifera L.) life stages, we used the BEEHAVE model to explore how increased mortalities of larvae, in-hive workers, and foragers, as well as reduced egg-laying rate, could impact colony dynamics over multiple years. Stresses were applied for 30 days, both as multiples of the modeled control mortality and as set percentage daily mortalities to assess the sensitivity of the modeled colony both to small fluctuations in mortality and periods of low to very high daily mortality. These stresses simulate stylized exposure of the different life stages to nectar and pollen contaminated with pesticide for 30 days. Increasing adult bee mortality had a much greater impact on colony survival than mortality of bee larvae or reduction in egg laying rate. Importantly, the seasonal timing of the imposed mortality affected the magnitude of the impact at colony level. In line with the LD50, we propose a new index of "lethal imposed stress": the LIS50 which indicates the level of stress on individuals that results in 50% colony mortality. This (or any LISx) is a comparative index for exploring the effects of different stressors at colony level in model simulations. While colony failure is not an acceptable protection goal, this index could be used to inform the setting of future regulatory protection goals.

  6. Monoclonal origin of B lymphocyte colony-forming cells in spleen colonies formed by multipotential hemopoietic stem cells

    PubMed Central

    Lala, PK; Johnson, GR

    1978-01-01

    Spleen colonies produced by transplanting lethally irradiated mice with either 12 day fetal liver or adult bone marrow cells were found to contain B- lymphocyte colony-forming cells (BL-CFC) . The proportion of BL-CFC positive spleen colonies did not increase substantially between 8 and 14 days after transplantation, the range being 18-45 percent. However, the absolute number of BL-CFC per spleen colony varied considerably (between 1 and 10,318), although the majority of colonies contained less than 200 BL-CFC. Irrespective of the time after transplantation, smaller spleen colonies were found to have a higher frequency of BL-CFC than larger spleen colonies. To determine the possible clonal origin of BL-CFC from spleen colony- forming unit (CFU-S), CBA mice were injected with equal numbers of CBA and CBA T(6)/T(6) fetal liver or adult bone marrow cells. Analysis of 7-15-day spleen colonies demonstrated that 90 percent were either exclusively T(6) positive or T(6) negative and approximately equal numbers ofboth colony types were observed. B-lymphocyte colonies were grown and successfully karyotyped from 19 spleen colonies. When compared with the original spleen colony karyotype the B-lymphocyte colony cells karyotype was identical in all 19 cases. In 3 of the 19 colonies analyzed a mixture of T(6) positive and T(6) negative karyotypes was present and identical proportions of the karyotypes were present in the pooled B-lymphocyte colony cells and spleen colony cells. The data indicate that the B-lymphocyte colony-forming cells detected in spleen colonies are genuine members of the hemopoietic clone derived from the initiating hemopoietic stem cell (CFU-S). PMID:309918

  7. Order and instabilities in dense bacterial colonies

    NASA Astrophysics Data System (ADS)

    Tsimring, Lev

    2012-02-01

    The structure of cell colonies is governed by the interplay of many physical and biological factors, ranging from properties of surrounding media to cell-cell communication and gene expression in individual cells. The biomechanical interactions arising from the growth and division of individual cells in confined environments are ubiquitous, yet little work has focused on this fundamental aspect of colony formation. By combining experimental observations of growing monolayers of non-motile strain of bacteria Escherichia coli in a shallow microfluidic chemostat with discrete-element simulations and continuous theory, we demonstrate that expansion of a dense colony leads to rapid orientational alignment of rod-like cells. However, in larger colonies, anisotropic compression may lead to buckling instability which breaks perfect nematic order. Furthermore, we found that in shallow cavities feedback between cell growth and mobility in a confined environment leads to a novel cell streaming instability. Joint work with W. Mather, D. Volfson, O. Mondrag'on-Palomino, T. Danino, S. Cookson, and J. Hasty (UCSD) and D. Boyer, S. Orozco-Fuentes (UNAM, Mexico).

  8. Policing native pleasures: a colonial history.

    PubMed

    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.

  9. English Literatures in Post-Colonial Singapore

    ERIC Educational Resources Information Center

    Dass, Rozita

    2015-01-01

    The emergence of a vibrant literary, culture and arts scene promotes Singapore's claims as a hub for arts and culture in the Asian region, and as a global arts city by the 21st century. The richness and variety of Singapore literature from the early post-colonial years are evident in the evolution of a Singapore literary culture. The diaspora of…

  10. Colonial Continuities and Educational Inequalities in Indonesia.

    ERIC Educational Resources Information Center

    Carpenter, Harold F., Jr.

    This paper explores the effect of 350 years of Dutch colonial rule upon Indonesian educational policies and the resulting regional inequalities in education. It was Dutch policy not to educate most of the children from the poorer social classes, but to use education to maintain and strengthen the existing social structure. Education was also used…

  11. Metatranscriptomic analyses of honey bee colonies

    USDA-ARS?s Scientific Manuscript database

    Honey bees face numerous biotic threats from viruses to bacteria, fungi, protists, and mites. Here we describe a thorough analysis of microbes harbored by worker honey bees collected from field colonies in geographically distinct regions of Turkey. Turkey is one of the World’s most important centers...

  12. Project Final Report: HPC-Colony II

    SciTech Connect

    Jones, Terry R; Kale, Laxmikant V; Moreira, Jose

    2013-11-01

    This report recounts the HPC Colony II Project which was a computer science effort funded by DOE's Advanced Scientific Computing Research office. The project included researchers from ORNL, IBM, and the University of Illinois at Urbana-Champaign. The topic of the effort was adaptive system software for extreme scale parallel machines. A description of findings is included.

  13. Branching instability in expanding bacterial colonies

    PubMed Central

    Giverso, Chiara; Verani, Marco; Ciarletta, Pasquale

    2015-01-01

    Self-organization in developing living organisms relies on the capability of cells to duplicate and perform a collective motion inside the surrounding environment. Chemical and mechanical interactions coordinate such a cooperative behaviour, driving the dynamical evolution of the macroscopic system. In this work, we perform an analytical and computational analysis to study pattern formation during the spreading of an initially circular bacterial colony on a Petri dish. The continuous mathematical model addresses the growth and the chemotactic migration of the living monolayer, together with the diffusion and consumption of nutrients in the agar. The governing equations contain four dimensionless parameters, accounting for the interplay among the chemotactic response, the bacteria–substrate interaction and the experimental geometry. The spreading colony is found to be always linearly unstable to perturbations of the interface, whereas branching instability arises in finite-element numerical simulations. The typical length scales of such fingers, which align in the radial direction and later undergo further branching, are controlled by the size parameters of the problem, whereas the emergence of branching is favoured if the diffusion is dominant on the chemotaxis. The model is able to predict the experimental morphologies, confirming that compact (resp. branched) patterns arise for fast (resp. slow) expanding colonies. Such results, while providing new insights into pattern selection in bacterial colonies, may finally have important applications for designing controlled patterns. PMID:25652464

  14. Teaching the History of Colonial Peru.

    ERIC Educational Resources Information Center

    Campbell, Leon G.

    1981-01-01

    Presents a bibliographic review essay on the topic of colonial Peru organized according to the following topics: Pre-Columbian Peru, 5500 B.C.- 1532; the conquest of Peru, 1532-1572; Peru under the Hapsburgs, 1516-1700; Bourbon Peru, 1700-1808; and the coming of independence, 1808-1821. The essay is based on a bibliography composed largely of…

  15. Honeybee colonies achieve fitness through dancing.

    PubMed

    Sherman, Gavin; Visscher, P Kirk

    2002-10-31

    The honeybee dance language, in which foragers perform dances containing information about the distance and direction to food sources, is the quintessential example of symbolic communication in non-primates. The dance language has been the subject of controversy, and of extensive research into the mechanisms of acquiring, decoding and evaluating the information in the dance. The dance language has been hypothesized, but not shown, to increase colony food collection. Here we show that colonies with disoriented dances (lacking direction information) recruit less effectively to syrup feeders than do colonies with oriented dances. For colonies foraging at natural sources, the direction information sometimes increases food collected, but at other times it makes no difference. The food-location information in the dance is presumably important when food sources are hard to find, variable in richness and ephemeral. Recruitment based simply on arousal of foragers and communication of floral odour, as occurs in honeybees, bumble bees and some stingless bees, can be equally effective under other circumstances. Clarifying the condition-dependent payoffs of the dance language provides new insight into its function in honeybee ecology.

  16. Colonial Newspaper Reaction to the Somerset Decision.

    ERIC Educational Resources Information Center

    Bradley, Patricia

    To examine colonial American press coverage of the British court decision to free American slave James Somerset, a study was conducted to clarify why the decision worked as a victory for British abolitionists but was usually cited even in post-Revolution America in the passage of increasingly oppressive slave legislation. Twenty-three of the…

  17. Detection of Campylobacter Colonies using Hyperspectral Imaging

    USDA-ARS?s Scientific Manuscript database

    Isolation and detection of Campylobacter in foods via direct plating involves lengthy laboratory procedures including enrichments and microaerobic incubations, which take several days to a week. The incubation time for growing Campylobacter colonies in agar media is typically 24 hours to 48 hours. F...

  18. The Sphere of Women in Colonial America.

    ERIC Educational Resources Information Center

    Cook, Robert

    This project is a unit of six lessons designed to study and understand the roles and expectations of women in the colonial period. The unit provides an historical perspective on those expectations, examines how both men and women viewed the sphere of women, and how enlightened thought on this topic began to emerge during this revolutionary time.…

  19. English Literatures in Post-Colonial Singapore

    ERIC Educational Resources Information Center

    Dass, Rozita

    2015-01-01

    The emergence of a vibrant literary, culture and arts scene promotes Singapore's claims as a hub for arts and culture in the Asian region, and as a global arts city by the 21st century. The richness and variety of Singapore literature from the early post-colonial years are evident in the evolution of a Singapore literary culture. The diaspora of…

  20. Considerations for lunar colony communications systems

    NASA Technical Reports Server (NTRS)

    Dowling, Richard P.

    1992-01-01

    This paper addresses system aspects of communications for a lunar colony. Human factors are particularly noted. The practical aspects of communications infrastructure are emphasized rather than specific technologies. Communications needs for mission support and morale are discussed along with potential means of satisfying them. Problem areas are identified and some possible solutions are considered.

  1. Significance of Hemolytic Colonies in Throat Cultures

    PubMed Central

    Quinn, Robert W.; Lowry, P. Nye

    1969-01-01

    These studies indicate that a single strain of hemolytic streptococci almost exclusively predominates the bacterial flora in patients with streptococcal infections and in the carrier state. One can proceed with confidence that, in isolating streptococci from throat swabs cultured on blood-agar plates, only a single hemolytic colony need be picked for serological grouping and typing. PMID:4888863

  2. Education and Evangelism in the English Colonies

    ERIC Educational Resources Information Center

    Watras, Joseph

    2008-01-01

    This article considers two related educational endeavors of the Massachusetts colony. The first is the colonists' efforts to pass their religious traditions to their children. The second is the effort of missionaries to spread the Christian faith to Native Americans. In both cases, the colonists wanted their children and the American Indians to…

  3. Women in Colonial and Revolutionary America.

    ERIC Educational Resources Information Center

    Eisenberg, Bonnie; And Others

    Designed as a supplemental teaching tool for upper elementary and middle school use, this unit contains information on the circumstances under which women of various cultures lived in the United States during the colonial and revolutionary periods and presents a perspective that is seldom included in textbooks. The unit includes biographies of ten…

  4. Colony Fusion in a Parthenogenetic Ant, Pristomyrmex punctatus

    PubMed Central

    Satow, Show; Satoh, Toshiyuki; Hirota, Tadao

    2013-01-01

    In the ant Pristomyrmex punctatus Smith (Hymenoptera: Formicidae), all young workers lay a small number of eggs parthenogenetically. Some colonies consist of monoclonal individuals that provide high inclusive fitness, according to the kin selection theory. However, in some populations, a majority of the colonies contain multiple lineages. Intracolonial genetic variation of parthenogenetic ants cannot be explained by the multiple mating of single founderesses or by the foundation of a colony by multiple foundresses, which are the usual causes of genetically diverse colonies in social insects. Here, we hypothesized that the fusion of established colonies might facilitate the formation of multiclonal colonies. Colony fusion decreases indirect benefits because of the reduction in intracolonial relatedness. However, when suitable nesting places for overwintering are scarce, colony fusion provides a strategy for the survival of colonies. Here, ants derived from different colonies were allowed to encounter one another in a container with just one nesting place. Initially, high aggression was observed; however, after several days, no aggression was observed and the ants shared the nest. When the fused colonies were allowed to transfer to two alternative nests, ants from different colonies occupied the same nest. This study highlights the importance of limiting the number of nesting places in order to understand the genetic diversity of parthenogenetic ant colonies. PMID:23895053

  5. An American termite in Paris: temporal colony dynamics.

    PubMed

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

    2017-09-22

    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.

  6. Clonal origin of human erythro-eosinophilic colonies in culture.

    PubMed

    Nakahata, T; Spicer, S S; Ogawa, M

    1982-04-01

    We have observed the presence of erythropoietic bursts containing eosinophils and their precursors in methylcellulose culture of human peripheral blood and marrow nucleated cells in the presence of erythropoietin and medium conditioned by phytohemagglutinin-stimulated leukocytes (PHA-LCM). It was possible to identify these bursts (colonies) in situ in methylcellulose culture on the basis of their unique red and black colors. Transmission electron microscopy revealed that the constituent erythroid and eosinophilic cells lay intermixed with each other, and through close intercellular connections formed compact colonies and bursts consisting of several sub-colonies. Differential counts of individual erythro-eosinophil colonies (EEo colonies) revealed only a small percentage of blast cells in most of the colonies. Replating experiments of single EEo colonies yielded only eosinophilic colonies and clusters and erythroid colonies. The clonal nature of the EEo colonies was documented by analysis of Y-chromatin-positive cells in individual EEo colonies derived from cocultures of male and female peripheral blood mononuclear cells. Comparison of conditioned media indicated that PHA-LCM is the best stimulator for EEo colonies. These studies suggest that the differentiation capabilities of the progenitors for EEo colonies are restricted to erythroid and eosinophilic differentiation.

  7. Nest site and colony characteristics of wading birds in selected atlantic coast colonies

    USGS Publications Warehouse

    Beaver, D.L.; Osborn, R.G.; Custer, T.W.

    1980-01-01

    Nests of 5 spp. of wading birds [Egretta thula, Plegadis falcinellus, Florida caerulea, casmerodius albus and Hydranassa tricolor] were identified and marked during the breeding season at 6 locations from Maccachusetts [USA] to North Carolina [USA]. At the end of the breeding season, 12 characteristics of nest-site location were measured. Nest locations were mapped to examine dispersion and nearest neighbor relationships. Multivariate analysis were used to describe and compare sites and species. Variations in nest-sites between colonies were greater than between species; colonies differed mainly in the variety and size of vegetation. Birds preferred to nest in vegetation that offered relatively stable nest sites, and the dispersion of nests in the colonies was related to vegetative patterns. The interaction of these factors with the number of bird species and the abundance of birds in the colony determined whether nest sites were stratified, segregated or randomly distributed.

  8. A Quantitative Model of Honey Bee Colony Population Dynamics

    PubMed Central

    Khoury, David S.; Myerscough, Mary R.; Barron, Andrew B.

    2011-01-01

    Since 2006 the rate of honey bee colony failure has increased significantly. As an aid to testing hypotheses for the causes of colony failure we have developed a compartment model of honey bee colony population dynamics to explore the impact of different death rates of forager bees on colony growth and development. The model predicts a critical threshold forager death rate beneath which colonies regulate a stable population size. If death rates are sustained higher than this threshold rapid population decline is predicted and colony failure is inevitable. The model also predicts that high forager death rates draw hive bees into the foraging population at much younger ages than normal, which acts to accelerate colony failure. The model suggests that colony failure can be understood in terms of observed principles of honey bee population dynamics, and provides a theoretical framework for experimental investigation of the problem. PMID:21533156

  9. Influence of task switching costs on colony homeostasis

    NASA Astrophysics Data System (ADS)

    Jeanson, Raphaël; Lachaud, Jean-Paul

    2015-06-01

    In social insects, division of labour allows colonies to optimise the allocation of workers across all available tasks to satisfy colony requirements. The maintenance of stable conditions within colonies (homeostasis) requires that some individuals move inside the nest to monitor colony needs and execute unattended tasks. We developed a simple theoretical model to explore how worker mobility inside the nest and task switching costs influence the maintenance of stable levels of task-associated stimuli. Our results indicate that worker mobility in large colonies generates important task switching costs and is detrimental to colony homeostasis. Our study suggests that the balance between benefits and costs associated with the mobility of workers patrolling inside the nest depends on colony size. We propose that several species of ants with diverse life-history traits should be appropriate to test the prediction that the proportion of mobile workers should vary during colony ontogeny.

  10. A quantitative model of honey bee colony population dynamics.

    PubMed

    Khoury, David S; Myerscough, Mary R; Barron, Andrew B

    2011-04-18

    Since 2006 the rate of honey bee colony failure has increased significantly. As an aid to testing hypotheses for the causes of colony failure we have developed a compartment model of honey bee colony population dynamics to explore the impact of different death rates of forager bees on colony growth and development. The model predicts a critical threshold forager death rate beneath which colonies regulate a stable population size. If death rates are sustained higher than this threshold rapid population decline is predicted and colony failure is inevitable. The model also predicts that high forager death rates draw hive bees into the foraging population at much younger ages than normal, which acts to accelerate colony failure. The model suggests that colony failure can be understood in terms of observed principles of honey bee population dynamics, and provides a theoretical framework for experimental investigation of the problem.

  11. Deformed wing virus implicated in overwintering honeybee colony losses.

    PubMed

    Highfield, Andrea C; El Nagar, Aliya; Mackinder, Luke C M; Noël, Laure M-L J; Hall, Matthew J; Martin, Stephen J; Schroeder, Declan C

    2009-11-01

    The worldwide decline in honeybee colonies during the past 50 years has often been linked to the spread of the parasitic mite Varroa destructor and its interaction with certain honeybee viruses. Recently in the United States, dramatic honeybee losses (colony collapse disorder) have been reported; however, there remains no clear explanation for these colony losses, with parasitic mites, viruses, bacteria, and fungal diseases all being proposed as possible candidates. Common characteristics that most failing colonies share is a lack of overt disease symptoms and the disappearance of workers from what appears to be normally functioning colonies. In this study, we used quantitative PCR to monitor the presence of three honeybee viruses, deformed wing virus (DWV), acute bee paralysis virus (ABPV), and black queen cell virus (BQCV), during a 1-year period in 15 asymptomatic, varroa mite-positive honeybee colonies in Southern England, and 3 asymptomatic colonies confirmed to be varroa mite free. All colonies with varroa mites underwent control treatments to ensure that mite populations remained low throughout the study. Despite this, multiple virus infections were detected, yet a significant correlation was observed only between DWV viral load and overwintering colony losses. The long-held view has been that DWV is relatively harmless to the overall health status of honeybee colonies unless it is in association with severe varroa mite infestations. Our findings suggest that DWV can potentially act independently of varroa mites to bring about colony losses. Therefore, DWV may be a major factor in overwintering colony losses.

  12. Deconstructive Pedagogy and Ideological Demystification in Post-Colonial Pakistan

    ERIC Educational Resources Information Center

    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…

  13. French colonial medicine in Cambodia: reflections of governmentality.

    PubMed

    Trankell, Ing-Britt; Ovesen, Jan

    2004-04-01

    Studies of colonial medicine, mostly from former British colonies, have shown that colonial medical interventions mostly benefited the European colonisers and often had very little positive effects on the health of the native populations at large. A common assumption is that this was also the case for French colonial medicine in general, and for colonial medicine in Cambodia in particular, and that the unsatisfactory contemporary state of the medical services in the country may be partly explained by its colonial past. As a way to test this assumption, this paper presents an ethnography of colonial medicine in Cambodia in the first decades of the twentieth century. Documents in the Cambodian National Archives provided the primary sources, and their significance was assessed against the background of the authors' experience of medical anthropological research in contemporary Cambodia. Michel Foucault's concept of governmentality is used as the interpretative frame. Elements of colonial governmentality in the medical field included the promotion of modern medicine through the free dispensing of medicines and medical treatment and rudimentary medical training of members of the local population, as well as compulsory vaccinations and surveillance of the colonial subjects. It is concluded that both the idea of medicine as a 'tool of empire' and that of the colonial physician as a humanitarian hero are equally incomplete as general descriptions, and that specific ethnographies of medical policies and practices should be undertaken for particular colonial settings. This paper provides the first anthropological account of colonial medicine in Cambodia.

  14. Deconstructive Pedagogy and Ideological Demystification in Post-Colonial Pakistan

    ERIC Educational Resources Information Center

    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…

  15. Before 1776: The Massachusetts Bay Colony from Founding to Revolution.

    ERIC Educational Resources Information Center

    Gruenbaum, Thelma

    Designed for use at 4th-through-10th-grade level, this short history of the Massachusetts Bay Colony provides a view of colonial life style and culture prior to the American Revolution. The first sections discuss the Puritan migration and early settlement around Boston. Descriptions of colonial housing, furniture, food, clothing, clothing styles,…

  16. The Genesis of Public Relations in British Colonial Practice.

    ERIC Educational Resources Information Center

    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…

  17. Oversea Education and British Colonial Education 1929-63.

    ERIC Educational Resources Information Center

    Whitehead, Clive

    2003-01-01

    Focuses on an early twentieth century journal called "Oversea Education," designed to increase communication among British colonies, particularly for education, based on William Ormsby Gore's travels among the colonies. Describes Frank Ward's editorial work that championed the rights of colonial subjects to have better educational…

  18. Brazilian Higher Education from a Post-Colonial Perspective

    ERIC Educational Resources Information Center

    Leite, Denise

    2010-01-01

    This article examines Brazilian higher education (HE) politics from a post-colonial perspective. The term "post-colonial" originally referred to a historical period of colonial empires established by European nations. Nowadays, the term commonly distinguishes a field of contemporary studies of "defamiliarisation of the imperial…

  19. Deformed Wing Virus Implicated in Overwintering Honeybee Colony Losses ▿

    PubMed Central

    Highfield, Andrea C.; El Nagar, Aliya; Mackinder, Luke C. M.; Noël, Laure M.-L. J.; Hall, Matthew J.; Martin, Stephen J.; Schroeder, Declan C.

    2009-01-01

    The worldwide decline in honeybee colonies during the past 50 years has often been linked to the spread of the parasitic mite Varroa destructor and its interaction with certain honeybee viruses. Recently in the United States, dramatic honeybee losses (colony collapse disorder) have been reported; however, there remains no clear explanation for these colony losses, with parasitic mites, viruses, bacteria, and fungal diseases all being proposed as possible candidates. Common characteristics that most failing colonies share is a lack of overt disease symptoms and the disappearance of workers from what appears to be normally functioning colonies. In this study, we used quantitative PCR to monitor the presence of three honeybee viruses, deformed wing virus (DWV), acute bee paralysis virus (ABPV), and black queen cell virus (BQCV), during a 1-year period in 15 asymptomatic, varroa mite-positive honeybee colonies in Southern England, and 3 asymptomatic colonies confirmed to be varroa mite free. All colonies with varroa mites underwent control treatments to ensure that mite populations remained low throughout the study. Despite this, multiple virus infections were detected, yet a significant correlation was observed only between DWV viral load and overwintering colony losses. The long-held view has been that DWV is relatively harmless to the overall health status of honeybee colonies unless it is in association with severe varroa mite infestations. Our findings suggest that DWV can potentially act independently of varroa mites to bring about colony losses. Therefore, DWV may be a major factor in overwintering colony losses. PMID:19783750

  20. Colony Rheology: Active Arthropods Generate Flows

    NASA Astrophysics Data System (ADS)

    Daniels, Karen; Mann, Michael; Charbonneau, Patrick

    2015-03-01

    Hydrodynamic-like flows are observed in biological systems as varied as bacteria, insects, birds, fish, and mammals. Both the phenomenology (e.g. front instabilities, milling motions) and the interaction types (hydrodynamic, direct contact, psychological, excluded-volume) strongly vary between systems, but a question common to all of them is to understand the role of particle-scale fluctuations in controlling large-scale rheological behaviors. We will address these questions through experiments on a new system, Tyrolichus casei (cheese mites), which live in dense, self-mixing colonies composed of a mixture of living mites and inert flour/detritus. In experiments performed in a Hele-Shaw geometry, we observe that the rheology of a colony is strongly dependent on the relative concentration of active and inactive particles. In addition to spreading flows, we also observe that the system can generate convective circulation and auto-compaction.

  1. [Sudden die-off of honeybee colonies].

    PubMed

    Muz, Mustafa N

    2008-01-01

    Apis mellifera is used for honeybee keeping all over Turkey. Recently, honeybees have been suddenly disappearing for no apparent reason. It is presumed that some viral and parasitic honeybee pathogens are responsible for this. No medical research has been conducted to determine the pathologic causes of the sudden die-off of the honeybee colonies in Turkey as yet. This is of urgent importance for future of the honeybee industry.

  2. The colony-stimulating factors and cancer.

    PubMed

    Metcalf, Donald

    2013-12-01

    The colony-stimulating factors (CSFs) are the master regulators of granulocyte and macrophage populations. There are four different aspects of the connection between the CSFs and cancer: (a) the CSFs can accelerate the regeneration of protective white cells damaged by chemotherapy; (b) the CSFs can mobilize stem cells to the peripheral blood in convenient numbers for transplantation; (c) the CSFs can enhance anticancer immune responses and (d) the CSFs are potentially involved in the genesis of the myeloid leukemias.

  3. FY005 Accomplishments for Colony Project

    SciTech Connect

    Jones, T; Kale, L; Moreira, J; Mendes, C; Chakravorty, S; Inglett, T; Tauferner, A

    2005-07-05

    The Colony Project is developing operating system and runtime system technology to enable efficient general purpose environments on tens of thousands of processors. To accomplish this, we are investigating memory management techniques, fault management strategies, and parallel resource management schemes. Recent results show promising findings for scalable strategies based on processor virtualization, in-memory checkpointing, and parallel aware modifications to full featured operating systems.

  4. The Development of Politics in Extraterrestrial Colonies

    NASA Astrophysics Data System (ADS)

    Sivier, D. J.

    The existence of feudal or totalitarian interplanetary empires has been a favourite theme in Science Fiction. Although the vast distances between the stars make the emergence of an interstellar empire impossible without the creation of a faster than light drive, this is not necessarily true for the other worlds within our solar system. Environmental constraints on the off-world colonies themselves, and repressive, hierarchical and feudalistic social and commercial institutions and customs inherited from the parent cultures on Earth and a tradition of military rule descending from the foundation of these colonies may all work to bring about a new feudal or totalitarian social order on humanity's extraterrestrial colonies. There are encouraging signs that this may not be the case, however. Already the debate over the projected colonisation of Mars is a factor influencing present controversies over repressive institutions and customs. Nevertheless, those wishing for a free, democratic, and politically, socially and technologically innovative and vigorous human society spreading throughout the solar system should not become complacent.

  5. Swarming Ring Patterns in Bacterial Colonies Exposed to Ultraviolet Radiation

    SciTech Connect

    Delprato, Anna M.; Samadani, Azadeh; Kudrolli, A.; Tsimring, L. S.

    2001-10-08

    We report a novel morphological transition in a Bacillus subtilis colony initially growing under ambient conditions, after ultraviolet radiation exposure. The bacteria in the central regions of the colonies are observed to migrate towards the colony edge forming a ring during uniform spatial exposure. When the radiation is switched off, the colonies were observed to grow both inward into the evacuated regions as well as outward indicating that the pattern is not formed due to depletion of nutrients at the center of the colony. We also propose a reaction-diffusion model in which waste-limited chemotaxis initiated by the UV radiation leads to the observed phenomenology.

  6. Morphological Diversity of the Colony Produced by Bacteria Proteus mirabilis

    NASA Astrophysics Data System (ADS)

    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.

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

    PubMed

    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.

  8. Rapid behavioral maturation accelerates failure of stressed honey bee colonies

    PubMed Central

    Perry, Clint J.; Myerscough, Mary R.; Barron, Andrew B.

    2015-01-01

    Many complex factors have been linked to the recent marked increase in honey bee colony failure, including pests and pathogens, agrochemicals, and nutritional stressors. It remains unclear, however, why colonies frequently react to stressors by losing almost their entire adult bee population in a short time, resulting in a colony population collapse. Here we examine the social dynamics underlying such dramatic colony failure. Bees respond to many stressors by foraging earlier in life. We manipulated the demography of experimental colonies to induce precocious foraging in bees and used radio tag tracking to examine the consequences of precocious foraging for their performance. Precocious foragers completed far fewer foraging trips in their life, and had a higher risk of death in their first flights. We constructed a demographic model to explore how this individual reaction of bees to stress might impact colony performance. In the model, when forager death rates were chronically elevated, an increasingly younger forager force caused a positive feedback that dramatically accelerated terminal population decline in the colony. This resulted in a breakdown in division of labor and loss of the adult population, leaving only brood, food, and few adults in the hive. This study explains the social processes that drive rapid depopulation of a colony, and we explore possible strategies to prevent colony failure. Understanding the process of colony failure helps identify the most effective strategies to improve colony resilience. PMID:25675508

  9. Rapid behavioral maturation accelerates failure of stressed honey bee colonies.

    PubMed

    Perry, Clint J; Søvik, Eirik; Myerscough, Mary R; Barron, Andrew B

    2015-03-17

    Many complex factors have been linked to the recent marked increase in honey bee colony failure, including pests and pathogens, agrochemicals, and nutritional stressors. It remains unclear, however, why colonies frequently react to stressors by losing almost their entire adult bee population in a short time, resulting in a colony population collapse. Here we examine the social dynamics underlying such dramatic colony failure. Bees respond to many stressors by foraging earlier in life. We manipulated the demography of experimental colonies to induce precocious foraging in bees and used radio tag tracking to examine the consequences of precocious foraging for their performance. Precocious foragers completed far fewer foraging trips in their life, and had a higher risk of death in their first flights. We constructed a demographic model to explore how this individual reaction of bees to stress might impact colony performance. In the model, when forager death rates were chronically elevated, an increasingly younger forager force caused a positive feedback that dramatically accelerated terminal population decline in the colony. This resulted in a breakdown in division of labor and loss of the adult population, leaving only brood, food, and few adults in the hive. This study explains the social processes that drive rapid depopulation of a colony, and we explore possible strategies to prevent colony failure. Understanding the process of colony failure helps identify the most effective strategies to improve colony resilience.

  10. Improvements on colony morphology identification towards bacterial profiling.

    PubMed

    Sousa, Ana Margarida; Machado, Idalina; Nicolau, Ana; Pereira, Maria Olívia

    2013-12-01

    Colony morphology may be an indicator of phenotypic variation, this being an important adaptive process adopted by bacteria to overcome environmental stressors. Furthermore, alterations in colony traits may reflect increased virulence and antimicrobial resistance. Despite the potential relevance of using colony morphological traits, the influence of experimental conditions on colony morphogenesis has been scarcely studied in detail. This study aims to clearly and systematically demonstrate the impact of some variables, such as colony growth time, plate colony density, culture medium, planktonic or biofilm mode of growth and strain genetic background, on bacterial colony morphology features using two Pseudomonas aeruginosa strains. Results, based on 5-replicate experiments, demonstrated that all variables influenced colony morphogenesis and 18 different morphotypes were identified, showing different sizes, forms, colours, textures and margins. Colony growth time and composition of the medium were the variables that caused the highest impact on colony differentiation both derived from planktonic and biofilm cultures. Colony morphology characterization before 45 h of incubation was considered inadequate and TSA, a non-selective medium, provided more colony diversity in contrast to P. aeruginosa selective media. In conclusion, data obtained emphasized the need to perform comparisons between colony morphologies in equivalent experimental conditions to avoid misinterpretation of microbial diagnostics and biomedical studies. Since colony morphotyping showed to be a reliable method to evaluate phenotypic switching and also to infer about bacterial diversity in biofilms, these unambiguous comparisons between morphotypes may offer a quite valuable input to clinical diagnosis, aiding the decision-making towards the selection of the most suitable antibiotic and supportive treatments. © 2013.

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

    PubMed

    Bockoven, Alison A; Wilder, Shawn M; Eubanks, Micky D

    2015-01-01

    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.

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

    PubMed Central

    Bockoven, Alison A.; Wilder, Shawn M.; Eubanks, Micky D.

    2015-01-01

    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. PMID:26197456

  13. a Missing Link? - Mesoscale Distributions of Colonial Phaeocystis Antarctica and its Ghost Colonies in the Ross Sea

    NASA Astrophysics Data System (ADS)

    Smith, W.; McGillicuddy, D. J., Jr.; Olson, E.; Sosik, H. M.; Peacock, E.

    2016-02-01

    It is well established that the haptophyte Phaeocystis antarctica is a dominant member of the Ross Sea phytoplankton, contributing more than half of the annual production. Its broad spatial distribution has been documented by ship sampling, but its mesoscale variations are poorly known. In the PRISM (Processes Regulating Iron Supply at the Mesoscale) project in 2011, we deployed a Video Plankton Recorder (VPR) for 24 h between selected locations that had been identified by satellite images to have eddy-like features. As P. antarctica colonies are far larger than the VPR's camera resolution (2 mm vs. 40 µm), we were able to quantify colonial contributions to total fluorescence and particulate organic carbon, resolving distances of a few kms and depths of ca. 1 m. Within these surveys, we found unusual forms of colonies, which we subsequently deemed "ghost colonies"; that is, colonies that have largely lost their cells and have collapsed. While ghost colonies generally were located deeper in the water column than intact colonies, not all surface Phaeocystis blooms were associated with ghost colonies. For example, in one survey ghost colonies and intact colonial forms were present throughout the water column, but with distributions separated by depth; while in another survey, their distributions appeared to be spatially distinct in the horizontal. We hypothesize that ghost colonies are formed upon extreme micronutrient stress, which causes colonies to sink and cells to be liberated from colonies. Considerable mesoscale variability was noted in P. antarctica distributions and was related to oceanographic features. The mesoscale variations in both P. antarctica and its ghost colonies potentially have significant impacts on vertical fluxes and biogeochemical cycles in the Ross Sea.

  14. The Struggles of an Eternal American Colony

    DTIC Science & Technology

    2012-03-20

    United States and Puerto Rico (New York: New York University Press, 2004), 33. 23 17 Puerto Rico Charter of Autonomy of 1897, title III, art . 5...18 Ibid., title VII, art . 41. 19 Ibid., title IX, art . 63. 20 Pedro A. Malavet, America’s Colony: the Political and Cultural Conflict between the...United States and Puerto Rico, 38. 38 U.S. Constitution, art 4, sec. 3. 39 Dick Thornburgh, Puerto Rico’s Future: A Time to Decide (Washington, DC

  15. Combined Final Report for Colony II Project

    SciTech Connect

    Kale, Laxmikant; Jones, Terry; Moreira, Jose

    2013-10-23

    (This report was originally submmited by the lead PI (Terry Jones, ORNL) on October 22, 2013 to the program manager, Lucy Nowell. It is being submitted from University of Illinois in accordance with instructions). HPC Colony II seeks to provide portable performance for leadership class machines. Our strategy is based on adaptive system software that aims to make the intelligent decisions necessary to allow domain scientists to safely focus on their task at hand and allow the system software stack to adapt their application to the underlying architecture. This report describes the research undertaken towards these objectives and the results obtained over the performance period of the project.

  16. Josephine Baker: psychoanalysis and the colonial fetish.

    PubMed

    Cheng, Anne Anlin

    2006-01-01

    This paper traces an intricate path connecting racial fantasy, aesthetic judgment, and the larger cultural problem of inter-subjective recognition. In particular, the author examines the theme of fetishism, both sexual and racial, in a Western historical, colonial context, in order to unravel a set of disturbances that cohere around the racial fetish then and now. Taking the figure of an entertainment icon of the 1920s, Josephine Baker, as a case study, the author shows how the imagination of the colonizing white male was both articulated and disrupted by Baker as a ready-made representation of the cultural, racial, and sexual other.

  17. The colony-stimulating factors and cancer.

    PubMed

    Metcalf, Donald

    2010-06-01

    The four colony-stimulating factors (CSFs) are glycoproteins that regulate the generation and some functions of infection-protective granulocytes and macrophages. Recombinant granulocyte-CSF (G-CSF) and granulocyte-macrophage-CSF (GM-CSF) have now been used to increase dangerously low white blood cell levels in many millions of cancer patients following chemotherapy. These CSFs also release haematopoietic stem cells to the peripheral blood, and these cells have now largely replaced bone marrow as more effective populations for transplantation to cancer patients who have treatment-induced bone marrow damage.

  18. Spatiotemporal evolution of bacterial biofilm colonies

    NASA Astrophysics Data System (ADS)

    Wilking, James; Koehler, Stephan; Sinha, Naveen; Seminara, Agnese; Brenner, Michael; Weitz, David

    2014-03-01

    Many bacteria on earth live in surface-attached communities known as biofilms. Gene expression in a biofilm is typically varied, resulting in a variety of phenotypes within a single film. These phenotypes play a critical role in biofilm physiology and development. We use time-resolved, wide-field fluorescence microscopy to image triple-labeled fluorescent Bacillus Subtilis colonies grown on agar to determine in a non-invasive fashion the evolving phenotypes. We infer their transition rates from the resulting spatiotemporal maps of gene expression. Moreover, we correlate these transition rates with local measurements of nutrient concentration to determine the influence of extracellular signals on gene expression.

  19. Enhanced ant colony optimization for multiscale problems

    NASA Astrophysics Data System (ADS)

    Hu, Nan; Fish, Jacob

    2016-03-01

    The present manuscript addresses the issue of computational complexity of optimizing nonlinear composite materials and structures at multiple scales. Several solutions are detailed to meet the enormous computational challenge of optimizing nonlinear structures at multiple scales including: (i) enhanced sampling procedure that provides superior performance of the well-known ant colony optimization algorithm, (ii) a mapping-based meshing of a representative volume element that unlike unstructured meshing permits sensitivity analysis on coarse meshes, and (iii) a multilevel optimization procedure that takes advantage of possible weak coupling of certain scales. We demonstrate the proposed optimization procedure on elastic and inelastic laminated plates involving three scales.

  20. Intercellular Genomics of Subsurface Microbial Colonies

    SciTech Connect

    Ortoleva, Peter; Tuncay, Kagan; Gannon, Dennis; Meile, Christof

    2007-02-14

    This report summarizes progress in the second year of this project. The objective is to develop methods and software to predict the spatial configuration, properties and temporal evolution of microbial colonies in the subsurface. To accomplish this, we integrate models of intracellular processes, cell-host medium exchange and reaction-transport dynamics on the colony scale. At the conclusion of the project, we aim to have the foundations of a predictive mathematical model and software that captures the three scales of these systems – the intracellular, pore, and colony wide spatial scales. In the second year of the project, we refined our transcriptional regulatory network discovery (TRND) approach that utilizes gene expression data along with phylogenic similarity and gene ontology analyses and applied it successfully to E.coli, human B cells, and Geobacter sulfurreducens. We have developed a new Web interface, GeoGen, which is tailored to the reconstruction of microbial TRNs and solely focuses on Geobacter as one of DOE’s high priority microbes. Our developments are designed such that the frameworks for the TRND and GeoGen can readily be used for other microbes of interest to the DOE. In the context of modeling a single bacterium, we are actively pursuing both steady-state and kinetic approaches. The steady-state approach is based on a flux balance that uses maximizing biomass growth rate as its objective, subjected to various biochemical constraints, for the optimal values of reaction rates and uptake/release of metabolites. For the kinetic approach, we use Karyote, a rigorous cell model developed by us for an earlier DOE grant and the DARPA BioSPICE Project. We are also investigating the interplay between bacterial colonies and environment at both pore and macroscopic scales. The pore scale models use detailed representations for realistic porous media accounting for the distribution of grain size whereas the macroscopic models employ the Darcy-type flow

  1. [FUNCTIONAL DIFFERENTIATION IN BRYOZOAN COLONY: A PROTEOMIC ANALYSIS].

    PubMed

    Kutyumov, V A; Maltseva, A L; Kotenko, N; Ostrovsky, A N

    2016-01-01

    Bryozoans are typical modular organisms. They consist of repetitive structural units, the zooids. Bryozoan colonies grow by zooidal budding, with the distribution pattern of the budding loci underlying the diversity of colony forms. Budding is usually restricted to the zooids at the periphery of the colony, which form a "growing edge" or local terminal growth zones. Non-budding parts of the colony can be functionally subdivided, too. In many species colonies consists of regular, often repetitive zones of feeding and non-feeding modules, associated with a periodical degeneration and regeneration of the polypide, retractile tentacle crown with a gut and the accompanying musculature. So, there is functional differentiation in bryozoan colonies but its mechanisms are unknown. Presumably, budding and/or polypide recycling in different colony parts are induced or inhibited by certain determinants of functional specialization. An effective tool of their identification is the comparison of proteomes of functionally different zones. Here we report the results of proteomic analysis of three bryozoan species from the White Sea, which have a different colony form: Flustrellidra hispida, Terminoflustra membranaceotruncata and Securiflustra securifrons. Using differential two-dimensional electrophoresis (2D-DIGE), we compared proteomes of the growing edge and the zones consisting of feeding and non-feeding zooids in these species. We estimated the overall proteome variability, revealed proteins whose relative abundance gradually changed along the proximal-distal colony axis and suggested that they might be involved in the functional differentiation of the colony.

  2. Wading birds as biological indicators 1975 colony survey

    USGS Publications Warehouse

    Custer, T.W.; Osborn, R.G.

    1977-01-01

    The suitability of wading birds (herons and their allies) as biological indicators in the coastal environment were studied in 1975 by 8 teams of investigators which located and censused 198 colonies along the Atlantic coast from Maine to Florida [USA]. Over 1/4 million breeding birds [Ardea herodias, Butorides virescens, Florida caerulea, Bubulcus ibis, Dichromanassa rufescens, Casmerodius albus, Egretta thula, Hydranassa tricolor, Nycticorax nycticorax, Nyctanassa violacea, Mycteria americana, Plegadis falcinellus, Eudocimus albus and Ajaia ajaja] were censused. The number of species in colonies ranged from 1-11. The number of 1- and 2-spp. colonies increased from Florida to Maine. Colony size decreased from Florida to Maine. Wading bird colony sites are generally active each year and the number of colonies may have recently increased in some areas of the coast. Species composition and total population of colonies fluctuate from year to year. The breeding population of wading birds was correlated with the area of coastal wetlands by state. Five teams of investigators studied the reproductive biology of 9 spp. in 13 colonies. Mean clutch size, the percentage of nests in which 1 or more eggs hatched and the overall percentage of eggs that hatched differed among colonies for some species, but no latitudinal gradient was found in any of these characteristics for any species. The use of wading birds to their full potential as biological indicators requires further exploration: survey and reproductive success methods need to be tested, the survey of colonies repeated, available historical information assembled and habitat requirements measured.

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

    PubMed

    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.

  4. Pre-Colonial Systems of Writing and Post-Colonial Languages of Publication.

    ERIC Educational Resources Information Center

    Riney, Timothy J.

    1998-01-01

    Previous accounts of "europhone" status (anglophone, francophone, etc.) have inadequately addressed spoken-written differences as well as different post-colonial developments taken by Southeast Asia, South Asia, North Africa, and East Africa vis-a-vis those of West, Central, and Southern Africa. This article investigates the extent to…

  5. Disrupting the Coloniality of Being: Toward De-Colonial Ontologies in Philosophy of Education

    ERIC Educational Resources Information Center

    Richardson, Troy A.

    2012-01-01

    This essay works to bridge conversations in philosophy of education with decolonial theory. The author considers Margonis' (1999, 2011a, b) use of Rousseau (1979) and Heidegger (1962) in developing an ontological attitude that counters social hierarchies and promotes anti-colonial relations. While affirming this effort, the essay outlines a…

  6. Direct Colony Baiting of Termite Colonies: A Tool for Ecological Studies

    Treesearch

    Don McG. Ewart

    1991-01-01

    The benefits of direct colony baiting are described: bait substrates enclosed in polyvinyl chloride tubes are applied in direct contact with the galleries of the termite nest. Attention of researchers is drawn to the potential of this method for species other than the mound-building Coptotermes 1acteus. \\t

  7. The Contemporary Reality of Canadian Imperialism: Settler Colonialism and the Hybrid Colonial State

    ERIC Educational Resources Information Center

    Barker, Adam J.

    2009-01-01

    The author's fundamental contention is this: Canadian society remains driven by the logic of imperialism and engages in concerted colonial action against Indigenous peoples whose claims to land and self-determination continue to undermine the legitimacy of Canadian authority and hegemony. The imperial ambitions of the Canadian state and its…

  8. Disrupting the Coloniality of Being: Toward De-Colonial Ontologies in Philosophy of Education

    ERIC Educational Resources Information Center

    Richardson, Troy A.

    2012-01-01

    This essay works to bridge conversations in philosophy of education with decolonial theory. The author considers Margonis' (1999, 2011a, b) use of Rousseau (1979) and Heidegger (1962) in developing an ontological attitude that counters social hierarchies and promotes anti-colonial relations. While affirming this effort, the essay outlines a…

  9. Robert Garrett, Tasmanian penal colony surgeon: alcoholism, medical misadventure and the penal colony of Sarah Island.

    PubMed

    Stride, P

    2011-09-01

    Robert Garrett emigrated from Scotland to Van Diemen's Land (now Tasmania) in 1822. Within a few months of arrival he was posted to the barbaric penal colony in Macquarie Harbour, known as Sarah Island. His descent into alcoholism, medical misadventure and premature death were related to his largely unsupported professional environment and were, in many respects, typical of those subjected to this experience.

  10. Stable isotope enrichment in laboratory ant colonies: effects of colony age, metamorphosis, diet, and fat storage

    USDA-ARS?s Scientific Manuscript database

    Ecologists use stable isotopes to infer diets and trophic levels of animals in food webs, yet some assumptions underlying these inferences have not been thoroughly tested. We used laboratory-reared colonies of Solenopsis invicta Buren (Formicidae: Solenopsidini) to test the effects of metamorphosis,...

  11. Entombed pollen: A new condition in honey bee colonies associated with increased risk of colony mortality

    USDA-ARS?s Scientific Manuscript database

    Here we describe a new phenomenon, entombed pollen, which is highly associated with increased colony mortality. Entombed pollen appears as sunken, wax-covered cells amidst “normal”, uncapped cells of stored pollen, and the pollen contained within these cells is brick red in color. There appears to b...

  12. The Contemporary Reality of Canadian Imperialism: Settler Colonialism and the Hybrid Colonial State

    ERIC Educational Resources Information Center

    Barker, Adam J.

    2009-01-01

    The author's fundamental contention is this: Canadian society remains driven by the logic of imperialism and engages in concerted colonial action against Indigenous peoples whose claims to land and self-determination continue to undermine the legitimacy of Canadian authority and hegemony. The imperial ambitions of the Canadian state and its…

  13. Physicians of colonial India (1757–1900)

    PubMed Central

    Saini, Anu

    2016-01-01

    The period of British rule from 1757 to 1900 is marked by major sociopolitical changes and scientific breakthroughs that impacted medical systems, institutions, and practitioners in India. In addition, historians have debated whether the colonial regime used Western medicine as a tool to expand and legitimize its rule. This paper reviews the secondary literature on this subject with emphasis on the individual physicians. During this period, the practice of “Doctory” or Western medicine gained momentum in India, buoyed with the support of the British as well as Western-educated Indians. Many Indians were trained in Western medicine and employed by the administration as “native doctors” in the subordinate medical service, and the superior medical service by and large comprised Europeans. The colonial regime gradually withdrew most of its patronage to the indigenous systems of medicine. The practitioners of these systems, the vaidyas and the hakims, suffered significant loss of prestige against Western medicine's claims of being a more rational “superior” system of medicine. Some of them became purists and defended and promoted their systems, while others adopted the methods and ideas of Western medicine into their education and practice. European doctors now rarely interacted with practitioners of Indian systems, but seriously pursued research into medicinal plants and tropical diseases. There is no mention of specialist physicians in this period, and all physicians and surgeons were generalists. Folk practitioners continued to be popular among the masses. PMID:28217577

  14. A catalog of Louisiana's nesting seabird colonies

    USGS Publications Warehouse

    Fontenot, William R.; Cardiff, Steve W.; DeMay, Richard A.; Dittmann, Donna L.; Hartley, Stephen B.; Jeske, Clinton W.; Lorenz, Nicole; Michot, Thomas C.; Purrington, Robert Dan; Seymour, Michael; Vermillion, William G.

    2012-01-01

    collective habitats which comprise Louisiana's now fragile coastal zone have taken major hits from commercial/residential, oil & gas, and other industrial development, primarily in the form of coastal erosion exacerbated by these and other factors (Portnoy 1978, Spendelow and Patton 1988, Martin and Lester 1990, Green, et al. 2006). Moreover, during this same period, both geologic subsidence rates (Tornqvist et al. 2008) and mean sea-level (Tornqvist et al. 2002) have increased, along with significant tropical storm activity; all of which have combined to impact available marsh, barrier island, beach, and dredge spoil nesting habitat for waterbirds, especially seabirds, throughout the coastal zone of Louisiana. The primary objective of this publication is to detail those coastal Louisiana colonial seabird nesting sites for which we have reasonably accurate data, in a tabular, site-by-site format. All major survey (1976-2008) data of site-by-site seabird species counts, as well as several smaller data sets, referred to in the site history tables as “miscellaneous observations” obtained during the May-June seabird breeding period, are included. It is our hope that these data will provide a dependable foundation from which future colonial seabird nesting surveys might be planned and carried out, as well as showcase the importance of coastal Louisiana's seabird rookeries, and contribute to their conservation.

  15. COVASIAM: an Image Analysis Method That Allows Detection of Confluent Microbial Colonies and Colonies of Various Sizes for Automated Counting

    PubMed Central

    Corkidi, G.; Diaz-Uribe, R.; Folch-Mallol, J. L.; Nieto-Sotelo, J.

    1998-01-01

    In this work we introduce the confluent and various sizes image analysis method (COVASIAM), an automated colony count technique that uses digital imaging technology for detection and separation of confluent microbial colonies and colonies of various sizes growing on petri dishes. The proposed method takes advantage of the optical properties of the surfaces of most microbial colonies. Colonies in the petri dish are epi-illuminated in order to direct the reflection of concentrated light coming from a halogen lamp towards an image-sensing device. In conjunction, a multilevel threshold algorithm is proposed for colony separation and counting. These procedures improved the quantification of colonies showing confluence or differences in size. We tested COVASIAM with a sample set of microorganisms that form colonies with contrasting physical properties: Saccharomyces cerevisiae, Aspergillus nidulans, Escherichia coli, Azotobacter vinelandii, Pseudomonas aeruginosa, and Rhizobium etli. These physical properties range from smooth to hairy, from bright to opaque, and from high to low convexities. COVASIAM estimated an average of 95.47% (ς = 8.55%) of the manually counted colonies, while an automated method based on a single-threshold segmentation procedure estimated an average of 76% (ς = 16.27) of the manually counted colonies. This method can be easily transposed to almost every image-processing analyzer since the procedures to compile it are generically standard. PMID:9546177

  16. First Recorded Loss of an Emperor Penguin Colony in the Recent Period of Antarctic Regional Warming: Implications for Other Colonies

    PubMed Central

    Trathan, Philip N.; Fretwell, Peter T.; Stonehouse, Bernard

    2011-01-01

    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. PMID:21386883

  17. Playback of colony sound alters the breeding schedule and clutch size in zebra finch (Taeniopygia guttata) colonies

    PubMed Central

    Waas, Joseph R.; Colgan, Patrick W.; Boag, Peter T.

    2005-01-01

    The hypothesis that social stimulation, derived from the presence and activities of conspecifics, can hasten and synchronize breeding in colonies of birds was tested. A modified playback/recorder system was used to continuously exaggerate the amount of colony sound available to zebra finches throughout their courtship period. Males that heard ‘sound supplements’ generated from their own colony sang more than males in control colonies that did not receive playback; males that heard samples from a different colony, sang at an intermediate level. Females that were exposed to the vocalizations of their mate and playback from a colony other than their own, laid eggs earlier and more synchronously than females in control colonies. Females that heard the vocalizations of their mate along with playback samples generated from their own colony, laid eggs more synchronously but not earlier than control females. Both acoustic treatments caused females to lay larger clutches. Social stimulation influences the breeding schedule and clutch size in zebra finch colonies. If there are advantages associated with these effects, social stimulation may contribute to the maintenance of colonial breeding systems. PMID:15734692

  18. Playback of colony sound alters the breeding schedule and clutch size in zebra finch (Taeniopygia guttata) colonies.

    PubMed

    Waas, Joseph R; Colgan, Patrick W; Boag, Peter T

    2005-02-22

    The hypothesis that social stimulation, derived from the presence and activities of conspecifics, can hasten and synchronize breeding in colonies of birds was tested. A modified playback/recorder system was used to continuously exaggerate the amount of colony sound available to zebra finches throughout their courtship period. Males that heard 'sound supplements' generated from their own colony sang more than males in control colonies that did not receive playback; males that heard samples from a different colony, sang at an intermediate level. Females that were exposed to the vocalizations of their mate and playback from a colony other than their own, laid eggs earlier and more synchronously than females in control colonies. Females that heard the vocalizations of their mate along with playback samples generated from their own colony, laid eggs more synchronously but not earlier than control females. Both acoustic treatments caused females to lay larger clutches. Social stimulation influences the breeding schedule and clutch size in zebra finch colonies. If there are advantages associated with these effects, social stimulation may contribute to the maintenance of colonial breeding systems.

  19. Image feature extraction based multiple ant colonies cooperation

    NASA Astrophysics Data System (ADS)

    Zhang, Zhilong; Yang, Weiping; Li, Jicheng

    2015-05-01

    This paper presents a novel image feature extraction algorithm based on multiple ant colonies cooperation. Firstly, a low resolution version of the input image is created using Gaussian pyramid algorithm, and two ant colonies are spread on the source image and low resolution image respectively. The ant colony on the low resolution image uses phase congruency as its inspiration information, while the ant colony on the source image uses gradient magnitude as its inspiration information. These two ant colonies cooperate to extract salient image features through sharing a same pheromone matrix. After the optimization process, image features are detected based on thresholding the pheromone matrix. Since gradient magnitude and phase congruency of the input image are used as inspiration information of the ant colonies, our algorithm shows higher intelligence and is capable of acquiring more complete and meaningful image features than other simpler edge detectors.

  20. Periodic growth of Bacillus subtilis colonies on agar plates

    NASA Astrophysics Data System (ADS)

    Fujikawa, Hiroshi

    1992-10-01

    Bacillus subtilis colonies show periodic growth on agar plates. The organism has been observed to show several colony morphologies including diffusion-limited aggregation (DLA) type, dense branching morphology (DBM), Eden type, and spreading without producing openings. The agar concentration for the periodic growth is higher than that of DBM and lower than that of DLA or Eden type. The nutrient (peptone) concentration for the periodic growth is higher than that of DLA and DBM and lower than that of Eden type. The colony grows towards a place with higher peptone concentration. These findings suggest that the diffusion of nutrient particles, i.e. the concentration gradient of peptone particles at the growing perimeter of a colony, would be essentially involved in the periodic growth. The distance between concentric rings of a colony is constant and intervention between two colonies is not observed, unlike the Liesegang ring.

  1. Correlation between virulence and colony morphology in Vibrio vulnificus.

    PubMed Central

    Simpson, L M; White, V K; Zane, S F; Oliver, J D

    1987-01-01

    Of 38 isolates of Vibrio vulnificus examined, all avirulent strains produced only translucent colonies. All virulent strains, with the exception of biogroup 2 (eel pathogens), exhibited both opaque and translucent colonies. Isogenic morphotypes were examined for a variety of phenotypic and virulence traits. Only the ability to utilize transferrin-bound iron and the presence of a surface polysaccharide were found to correlate with colony opacity and virulence. Images PMID:2432016

  2. Colony patterning and collective hyphal growth of filamentous fungi

    NASA Astrophysics Data System (ADS)

    Matsuura, Shu

    2002-11-01

    Colony morphology of wild and mutant strains of Aspergillus nidulans at various nutrient and agar levels was investigated. Two types of colony patterning were found for these strains. One type produced uniform colonies at all nutrient and agar levels tested, and the other exhibited morphological change into disordered ramified colonies at low nutrient levels. Both types showed highly condensed compact colonies at high nutrient levels on low agar media that was highly diffusive. Disordered colonies were found to develop with low hyphal extension rates at low nutrient levels. To understand basic pattern selection rules, a colony model with three parameters, i.e., the initial nutrient level and the step length of nutrient random walk as the external parameters, and the frequency of nutrient uptake as an internal parameter, was constructed. At low nutrient levels, with decreasing nutrient uptake frequency under diffusive conditions, the model colony exhibited onsets of disordered ramification. Further, in the growth process of A. nidulans, reduction of hyphal extension rate due to a population effect of hyphae was found when hyphae form three-dimensional dense colonies, as compared to the case in which hyphal growth was restricted into two-dimensional space. A hyphal population effect was introduced in the colony model. Thickening of colony periphery due to the population effect became distinctive as the nutrient diffusion effect was raised at high nutrient levels with low hyphal growth rate. It was considered that colony patterning and onset of disorder were strongly governed by the combination of nutrient diffusion and hyphal growth rate.

  3. Colonial variation in Serratia marcescens together with antibiotic resistance.

    PubMed

    Ruhen, R W; Wetherall, F M

    1983-01-01

    A strain of Serratia marcescens, isolated from the blood cultures of a patient receiving antibiotics, exhibited 3 unstable properties. These properties were resistance to aminoglycosides, colony size and pigment production. While resistance to aminoglycosides was linked to colony size, pigment production appeared independent of the other 2 properties. When multiple variation of properties occurs in colonies isolated from clinical material, this still may represent a pure culture.

  4. Energy consumption of termite colonies of Nasutitermes ephratae (Isoptera: Termitidae).

    PubMed

    Muradian, R; Issa, S; Jaffe, K

    1999-07-01

    Measurements of CO2 production of whole termite colonies showed that respiration intensity varies slightly during the daily cycle, that the relation between standard metabolism and colony size is best described with a negative exponential, taking into account the proportion of the various castes. Larger colonies were more efficient in their energy use, suggesting that energetic considerations may contribute in explaining the maintenance in evolution of complex societies.

  5. Male fitness of honeybee colonies (Apis mellifera L.).

    PubMed

    Kraus, F B; Neumann, P; Scharpenberg, H; van Praagh, J; Moritz, R F A

    2003-09-01

    Honeybees (Apis mellifera L.) have an extreme polyandrous mating system. Worker offspring of 19 naturally mated queens was genotyped with DNA microsatellites, to estimate male reproductive success of 16 drone producing colonies. This allowed for estimating the male mating success on both the colony level and the level of individual drones. The experiment was conducted in a closed population on an isolated island to exclude interferences of drones from unknown colonies. Although all colonies had produced similar numbers of drones, differences among the colonies in male mating success exceeded one order of magnitude. These differences were enhanced by the siring success of individual drones within the offspring of mated queens. The siring success of individual drones was correlated with the mating frequency at the colony level. Thus more successful colonies not only produced drones with a higher chance of mating, but also with a significantly higher proportion of offspring sired than drones from less successful colonies. Although the life cycle of honeybee colonies is very female centred, the male reproductive success appears to be a major driver of natural selection in honeybees.

  6. Hierarchy length in orphaned colonies of the ant Temnothorax nylanderi

    NASA Astrophysics Data System (ADS)

    Heinze, J.

    2008-08-01

    Workers of the ant Temnothorax nylanderi form dominance orders in orphaned colonies in which only one or a few top-ranking workers begin to produce males from unfertilized eggs. Between one and 11 individuals initiated 80% of all aggression in 14 queenless colonies. As predicted from inclusive fitness models (Molet M, van Baalen M, Monnin T, Insectes Soc 52:247 256, 2005), hierarchy length was found to first increase with colony size and then to level off at larger worker numbers. The frequency and skew of aggression decreased with increasing size, indicating that rank orders are less pronounced in larger colonies.

  7. Colony site dynamics and habitat use in Atlantic coast seabirds

    USGS Publications Warehouse

    Erwin, R.M.; Galli, J.; Burger, J.

    1981-01-01

    Seabird colony sizes and movements were documented in the DelMarVa coastal region in 1976-1977 and in New Jersey in 1978-1979. Most colonies were found on marsh and dredge deposition islands and on barrier island beaches. For the 'traditionally' beach-nesting Herring Gull, Common Tern, and Black Skimmer, larger, more stable colonies were found on barrier beaches than on marsh islands. In marsh habitats, rates of colony-site change of marshnesting Forster's Tern and Laughing Gulls were similar to those of the former beach nesters. Several adaptations have evolved in marsh specialists to cope with a high risk of reproductive failure due to flooding, but both Herring Gulls and Common Terns also appear to be very adaptable in nesting under various habitat conditions. New colonies and those abandoned between years may be pioneering attempts by younger or inexperienced birds, because they are often smaller than persistent colonies, although patterns differ among areas and habitats. Colony-site dynamics are complex and result from many selective factors including competition, predation, physical changes in site structure, and flooding. The invasion of Herring Gulls into marshes along the mid-Atlantic coast has had an impact on new colony-site choice by associated seabirds. Calculating colony-site turnover rates allows for comparisons among species, habitats, and regions and may give useful insights into habitat quality and change and alternative nesting strategies

  8. Improved Ant Colony Clustering Algorithm and Its Performance Study.

    PubMed

    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.

  9. Varroa-virus interaction in collapsing honey bee colonies.

    PubMed

    Francis, Roy M; 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 to be carried over with the bees into the next season. In general, AKI and DWV titres did not show any notable response to the treatment and steadily increased over the season from April to October. In the untreated control group, titres increased most dramatically. Viral copies were correlated to number of varroa mites. Most colonies that collapsed over the winter had significantly higher AKI and DWV titres in October compared to survivors. Only treated colonies survived the winter. We discuss our results in relation to the varroa-virus model developed by Stephen Martin.

  10. Varroa-Virus Interaction in Collapsing Honey Bee Colonies

    PubMed Central

    Francis, Roy M.; 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 to be carried over with the bees into the next season. In general, AKI and DWV titres did not show any notable response to the treatment and steadily increased over the season from April to October. In the untreated control group, titres increased most dramatically. Viral copies were correlated to number of varroa mites. Most colonies that collapsed over the winter had significantly higher AKI and DWV titres in October compared to survivors. Only treated colonies survived the winter. We discuss our results in relation to the varroa-virus model developed by Stephen Martin. PMID:23526946

  11. Improved Ant Colony Clustering Algorithm and Its Performance Study

    PubMed Central

    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

  12. Nitrogen fixation by intact colonies of the termite Nasutitermes corniger.

    PubMed

    Prestwich, G D; Bentley, B L

    1981-05-01

    Whole colonies of the arboreal termite Nasutitermes corniger (lsoptera, Termitidae, Nasutitermitinae) from a Costa Rican rainforest were assayed for nitrogen fixation by the acetylene reduction method, using a 21-1 test chamber. Nitrogenase activity was positively correlated with termite biomass for the nexts examined, providing the experiment was performed within 2 h of removal of the colony from the field. Total colony fixation rates of 0.25-1.0 mg N per colony per hour indicate a nitrogen doubling time of 200-600 days, thereby making possible complete replacement of the nest population 1-2 times per year.

  13. Concepts for an export oriented lunar colony

    NASA Astrophysics Data System (ADS)

    Miller, Kent L.

    1990-12-01

    A model of a lunar domestic economy is presented which consists of 12 sectors, trading 21 goods and services. Material flow for operations and investments are balanced to minimize shortages and surpluses. Prices are formed by targeting a 15-35% return on assets for industry and a 15% after expenses income for labour. From this data, accounting statements, a 14 × 14 cash flow input/output matrix (consisting of 11 industrial sectors, labour, foreign trade and finance), and macroeconomic analyses are prepared which illuminate the most important links in the lunar economy. From this model conclusions are drawn regarding the matter of how best to lay the basis for sustainable colony growth and prosperity.

  14. A new colonial type of N. gonorrhoeae.

    PubMed Central

    Chan, K; Wiseman, G M

    1975-01-01

    A new variant of Neisseria gonorrhoeae, designated Type 1(1), is described. Colonies of the new type resemble those of Types 1 and 2 in physical characteristics but are granular with a slightly crenated edge and are a deeper gold in colour. The virulence of Type 1(1) in the chick embryo is in keeping with that of Types 1 and 2 but is significantly different from Types 3, 4, and 5. Type 1(1) could be maintained in the laboratory for 6 months, provided that daily selective subcultures were performed. In the absence of this, Type 1(1) reverted to Type 5. It was also possible to preserve the stability of Type 1(1) for long periods by immersion in liquid nitrogen. Pili have been demonstrated on the new type. Images PMID:808249

  15. Optic disc detection using ant colony optimization

    NASA Astrophysics Data System (ADS)

    Dias, Marcy A.; Monteiro, Fernando C.

    2012-09-01

    The retinal fundus images are used in the treatment and diagnosis of several eye diseases, such as diabetic retinopathy and glaucoma. This paper proposes a new method to detect the optic disc (OD) automatically, due to the fact that the knowledge of the OD location is essential to the automatic analysis of retinal images. Ant Colony Optimization (ACO) is an optimization algorithm inspired by the foraging behaviour of some ant species that has been applied in image processing for edge detection. Recently, the ACO was used in fundus images to detect edges, and therefore, to segment the OD and other anatomical retinal structures. We present an algorithm for the detection of OD in the retina which takes advantage of the Gabor wavelet transform, entropy and ACO algorithm. Forty images of the retina from DRIVE database were used to evaluate the performance of our method.

  16. Ant Colony Optimization with Cunning Ants

    NASA Astrophysics Data System (ADS)

    Tsutsui, Shigeyoshi

    In this paper, we propose the cAS, a new ACO algorithm, and evaluate the performance using TSP instances available at TSPLIB. The results show that cAS works well on the test instances and has performance that may be one of the most promising ACO algorithms. We also evaluate cAS when it is combined with LK local search heuristic using larger sized TSP instances. The results also show promising performance. cAS introduced two important schemes. One is to use the colony model divided into units, which has a stronger exploitation feature while maintaining a certain degree of diversity among units. The other is to use a scheme, we call cunning, when constructing new solutions, which can prevent premature stagnation by reducing strong positive feedback to the trail density.

  17. Modelling the morphology of migrating bacterial colonies

    NASA Astrophysics Data System (ADS)

    Nishiyama, A.; Tokihiro, T.; Badoual, M.; Grammaticos, B.

    2010-08-01

    We present a model which aims at describing the morphology of colonies of Proteus mirabilis and Bacillus subtilis. Our model is based on a cellular automaton which is obtained by the adequate discretisation of a diffusion-like equation, describing the migration of the bacteria, to which we have added rules simulating the consolidation process. Our basic assumption, following the findings of the group of Chuo University, is that the migration and consolidation processes are controlled by the local density of the bacteria. We show that it is possible within our model to reproduce the morphological diagrams of both bacteria species. Moreover, we model some detailed experiments done by the Chuo University group, obtaining a fine agreement.

  18. Dynamics of the presence of israeli acute paralysis virus in honey bee colonies with colony collapse disorder.

    PubMed

    Hou, Chunsheng; Rivkin, Hadassah; Slabezki, Yossi; Chejanovsky, Nor

    2014-05-05

    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.

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

    PubMed Central

    Hou, Chunsheng; Rivkin, Hadassah; Slabezki, Yossi; Chejanovsky, Nor

    2014-01-01

    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. PMID:24800677

  20. Marking individual ants for behavioral sampling in a laboratory colony.

    PubMed

    Holbrook, C Tate

    2009-07-01

    Ant societies are tractable and malleable, two features that make them ideal models for probing the organization of complex biological systems. The ability to identify specific individuals while they function as part of a colony permits an integrative analysis of social complexity, including self-organizational processes (i.e., how individual-level properties and social interactions give rise to emergent, colony-level attributes such as division of labor and collective decision making). Effects of genotype, nutrition, and physiology on individual behavior and the organization of work also can be investigated in this manner, through correlative and manipulative approaches. Moreover, aspects of colony demography (e.g., colony size, and age and size distributions of workers) can be altered experimentally to examine colony development and regulatory mechanisms underlying colony homeostasis and resiliency. This protocol describes how to sample the behavior of ants living in a colony under laboratory conditions. Specifically, it outlines how to identify and observe individuals within a colony, an approach that can be used to quantify individual- and colony-level patterns of behavior. When a lower-resolution measure of overall group behavior is desired, individual identities might not be required. Given the diversity of ants and their study, this protocol provides a very general methodology; the details can be modified according to the body size, colony size, and ecology of the focal species, as well as to specific research aims. These basic techniques can also be extended to more advanced experimental designs such as manipulation of colony demography and hormone treatment.

  1. A new preclinical 3-dimensional agarose colony formation assay.

    PubMed

    Kajiwara, Yoshinori; Panchabhai, Sonali; Levin, Victor A

    2008-08-01

    The evaluation of new drug treatments and combination treatments for gliomas and other cancers requires a robust means to interrogate wide dose ranges and varying times of drug exposure without stain-inactivation of the cells (colonies). To this end, we developed a 3-dimensional (3D) colony formation assay that makes use of GelCount technology, a new cell colony counter for gels and soft agars. We used U251MG, SNB19, and LNZ308 glioma cell lines and MiaPaCa pancreas adenocarcinoma and SW480 colon adenocarcinoma cell lines. Colonies were grown in a two-tiered agarose that had 0.7% agarose on the bottom and 0.3% agarose on top. We then studied the effects of DFMO, carboplatin, and SAHA over a 3-log dose range and over multiple days of drug exposure. Using GelCount we approximated the area under the curve (AUC) of colony volumes as the sum of colony volumes (microm2xOD) in each plate to calculate IC50 values. Adenocarcinoma colonies were recognized by GelCount scanning at 3-4 days, while it took 6-7 days to detect glioma colonies. The growth rate of MiaPaCa and SW480 cells was rapid, with 100 colonies counted in 5-6 days; glioma cells grew more slowly, with 100 colonies counted in 9-10 days. Reliable log dose versus AUC curves were observed for all drugs studied. In conclusion, the GelCount method that we describe is more quantitative than traditional colony assays and allows precise study of drug effects with respect to both dose and time of exposure using fewer culture plates.

  2. Ant Colonies Do Not Trade-Off Reproduction against Maintenance.

    PubMed

    Kramer, Boris H; Schrempf, Alexandra; Scheuerlein, Alexander; Heinze, Jürgen

    2015-01-01

    The question on how individuals allocate resources into maintenance and reproduction is one of the central questions in life history theory. Yet, resource allocation into maintenance on the organismic level can only be measured indirectly. This is different in a social insect colony, a "superorganism" where workers represent the soma and the queen the germ line of the colony. Here, we investigate whether trade-offs exist between maintenance and reproduction on two levels of biological organization, queens and colonies, by following single-queen colonies of the ant Cardiocondyla obscurior throughout the entire lifespan of the queen. Our results show that maintenance and reproduction are positively correlated on the colony level, and we confirm results of an earlier study that found no trade-off on the individual (queen) level. We attribute this unexpected outcome to the existence of a positive feedback loop where investment into maintenance (workers) increases the rate of resource acquisition under laboratory conditions. Even though food was provided ad libitum, variation in productivity among the colonies suggests that resources can only be utilized and invested into additional maintenance and reproduction by the colony if enough workers are available. The resulting relationship between per-capita and colony productivity in our study fits well with other studies conducted in the field, where decreasing per-capita productivity and the leveling off of colony productivity have been linked to density dependent effects due to competition among colonies. This suggests that the absence of trade-offs in our laboratory study might also be prevalent under natural conditions, leading to a positive association of maintenance, (= growth) and reproduction. In this respect, insect colonies resemble indeterminate growing organisms.

  3. Pre-colonial culture, post-colonial economic success? The Tswana and the African economic miracle.

    PubMed

    Hjort, Jonas

    2010-01-01

    Cultural explanations of economic phenomena have recently enjoyed a renaissance among economists. This article provides further evidence for the salience of culture through an in-depth case study of one of the fastest-growing economies in the world during the last 50 years-Botswana. The unique culture that developed among the Tswana before and during the early days of colonialism, which shared many features with those of western nation-states, appears to have contributed significantly to the factors widely seen as determinants of Botswana's post-colonial economic success: state legitimacy, good governance and democracy, commercial traditions, well-established property rights, and inter-ethnic unity. Neighbouring Southern African cultures typically did not exhibit these traits.

  4. Effect of Corynebacterium parvum on colony-stimulating factor and granulocyte-macrophage colony formation.

    PubMed

    Foster, R S; MacPherson, B R; Browdie, D A

    1977-05-01

    Because Corynebacterium parvum has tumor-inhibitory properties and stimulates granulocyte-macrophage production, it may have clinical value in combination with chemotherapy. The leukopoietic effect of killed suspensions of C. parvum was studied in mice using the technique of in vitro clonal culture of hematopoietic cells. After C. parvum injection, there was a prompt, sustained elevation of serum colony-stimulating factor followed by an increase in granulocyte-macrophage precursor cells in the spleen and increases in blood mononuclear and granulocyte cells. Colony-stimulating factor production is suggested as a major mechanism of stimulation of granulocyte-macrophage proliferation by C. parvum. Since rapidly proliferating hematopoietic cells may have increased sensititity to cytotoxic agents, the details of hematopoietic stimulation by C. parvum may be critical in the sequential timing of combined C. parvum and chemotherapy treatment to obtain maximal tumor inhibition and minimal hematopoietic toxicity.

  5. Bacterial Colony: First Report of Donut Colony Morphology among Diphtheroids Isolated in Blood.

    PubMed

    Kandi, Venkataramana

    2015-11-04

    Isolation of diphtheroids in human clinical specimens is not uncommon. Several studies have highlighted the significance of these bacteria in human infection, which morphologically resemble Corynebacterium diphtheriae. Previous studies have noted that occurrence of these bacteria in specimens like the blood should not be ignored as they can result in serious infections like endocarditis and sepsis among debilitated individuals, including the neonates. We report isolation of diphtheroid bacterium in blood from a case of septicaemia showing donut colony morphology.

  6. Colonialism, Education and Rural Buddhist Communities in Bangladesh

    ERIC Educational Resources Information Center

    Barua, Bijoy

    2007-01-01

    This paper will excavate pre-independence (British/Pakistan) and post-independence colonial education interventions into Buddhist culture and education with the view to expose the nature and shape of colonial domination and related Buddhist efforts at cultural and educational decolonization. This will be accomplished by (a) considering a brief…

  7. Allee effects and colony collapse disorder in honey bees

    USDA-ARS?s Scientific Manuscript database

    We propose a mathematical model to quantify the hypothesis that a major ultimate cause of Colony Collapse Disorder (CCD) in honey bees is the presence of an Allee effect in the growth dynamics of honey bee colonies. In the model, both recruitment of adult bees as well as mortality of adult bees have...

  8. How natural infection by Nosema ceranae causes honeybee colony collapse.

    PubMed

    Higes, Mariano; Martín-Hernández, Raquel; Botías, Cristina; Bailón, Encarna Garrido; González-Porto, Amelia V; Barrios, Laura; Del Nozal, M Jesús; Bernal, José L; Jiménez, Juan J; Palencia, Pilar García; Meana, Aránzazu

    2008-10-01

    In recent years, honeybees (Apis mellifera) have been strangely disappearing from their hives, and strong colonies have suddenly become weak and died. The precise aetiology underlying the disappearance of the bees remains a mystery. However, during the same period, Nosema ceranae, a microsporidium of the Asian bee Apis cerana, seems to have colonized A. mellifera, and it's now frequently detected all over the world in both healthy and weak honeybee colonies. For first time, we show that natural N. ceranae infection can cause the sudden collapse of bee colonies, establishing a direct correlation between N. ceranae infection and the death of honeybee colonies under field conditions. Signs of colony weakness were not evident until the queen could no longer replace the loss of the infected bees. The long asymptomatic incubation period can explain the absence of evident symptoms prior to colony collapse. Furthermore, our results demonstrate that healthy colonies near to an infected one can also become infected, and that N. ceranae infection can be controlled with a specific antibiotic, fumagillin. Moreover, the administration of 120 mg of fumagillin has proven to eliminate the infection, but it cannot avoid reinfection after 6 months. We provide Koch's postulates between N. ceranae infection and a syndrome with a long incubation period involving continuous death of adult bees, non-stop brood rearing by the bees and colony loss in winter or early spring despite the presence of sufficient remaining pollen and honey.

  9. Commentary: Responses from Colonial Williamsburg Staff to Stoddard (2009)

    ERIC Educational Resources Information Center

    Lee, John K.; Hicks, David

    2009-01-01

    Jeremey Stoddard's article in this issue, "Toward a Virtual Field Trip Model for the Social Studies," describes his analysis of the Colonial Williamsburg Electronic Field Trip and a conceptual model for developing meaningful and successful electronic or virtual field trips. In an effort to contextualize the Colonial Williamsburg…

  10. Colonial Education: A History of Education in Belize.

    ERIC Educational Resources Information Center

    Lewis, Karla

    This paper discusses the education in Belize (formerly known as British Honduras) during the colonial era and the lasting impact of the educational foundation of the country. The paper examines the influence the British colonial educational system continues to have in Belize, 20 years after independence. It gives an overview of the history of…

  11. 36 CFR 7.1 - Colonial National Historical Park.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Colonial National Historical Park. 7.1 Section 7.1 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.1 Colonial National Historical Park. (a...

  12. 36 CFR 7.1 - Colonial National Historical Park.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Colonial National Historical Park. 7.1 Section 7.1 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.1 Colonial National Historical Park. (a...

  13. 36 CFR 7.1 - Colonial National Historical Park.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Colonial National Historical Park. 7.1 Section 7.1 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.1 Colonial National Historical Park. (a...

  14. 36 CFR 7.1 - Colonial National Historical Park.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Colonial National Historical Park. 7.1 Section 7.1 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.1 Colonial National Historical Park. (a...

  15. 36 CFR 7.1 - Colonial National Historical Park.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Colonial National Historical Park. 7.1 Section 7.1 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.1 Colonial National Historical Park. (a...

  16. Automatic counting and classification of bacterial colonies using hyperspectral imaging

    USDA-ARS?s Scientific Manuscript database

    Detection and counting of bacterial colonies on agar plates is a routine microbiology practice to get a rough estimate of the number of viable cells in a sample. There have been a variety of different automatic colony counting systems and software algorithms mainly based on color or gray-scale pictu...

  17. Parallelizing Ant Colony Optimization via Area of Expertise Learning

    DTIC Science & Technology

    2007-09-13

    ACS-TSP, is well-established and commonly used throughout the academic community. ACS-GRIDWORLD, on the other hand, represents a brand -new ant colony...van der Zwaan, S. and C. Marques . “Ant Colony Optimisation for Job Shop Scheduling”, 1999. URL citeseer.ist.psu.edu/vanderzwaan99ant.html. 103

  18. Space Colonies. Citations from the International Aerospace Abstracts data base

    NASA Technical Reports Server (NTRS)

    Zollars, G. F.

    1979-01-01

    Approximately 204 citations to the international literature concerning various aspects of space colonies are presented. Topics include the design and construction of space colonies, the effects on humans of long term life in a variety of spaceborne environments, and the potential uses of orbital space stations and lunar bases.

  19. Education "Reform" in Latino Detroit: Achievement Gap or Colonial Legacy?

    ERIC Educational Resources Information Center

    Gonzales, Sandra M.; Shields, Carolyn M.

    2015-01-01

    Using critical theory and an analysis of missionary reports and documentation describing education in colonial Puerto Rico and Mexico, the authors cross borders and time periods to socially and historically situate Spanish colonial educational methodologies and their contemporary use in one low-income Latino community in urban Detroit, Michigan.…

  20. Commentary: Responses from Colonial Williamsburg Staff to Stoddard (2009)

    ERIC Educational Resources Information Center

    Lee, John K.; Hicks, David

    2009-01-01

    Jeremey Stoddard's article in this issue, "Toward a Virtual Field Trip Model for the Social Studies," describes his analysis of the Colonial Williamsburg Electronic Field Trip and a conceptual model for developing meaningful and successful electronic or virtual field trips. In an effort to contextualize the Colonial Williamsburg…

  1. Slave Advertising in the Colonial Newspaper: Mirror to the Dilemma.

    ERIC Educational Resources Information Center

    Bradley, Patricia

    To explore racial attitudes from the colonial period of the United States, a study examined advertising practices regarding announcements dealing with black slaves in colonial newspapers in Massachusetts, New York, Pennsylvania, Maryland, Virginia, and South Carolina. Careful scrutiny revealed no relationship between the editorial stance of a…

  2. Modeling cell-matrix traction forces in Keratinocyte colonies

    NASA Astrophysics Data System (ADS)

    Banerjee, Shiladitya

    2013-03-01

    Crosstalk between cell-cell and cell-matrix adhesions plays an essential role in the mechanical function of tissues. The traction forces exerted by cohesive keratinocyte colonies with strong cell-cell adhesions are mostly concentrated at the colony periphery. In contrast, for weak cadherin-based intercellular adhesions, individual cells in a colony interact with their matrix independently, with a disorganized distribution of traction forces extending throughout the colony. In this talk I will present a minimal physical model of the colony as contractile elastic media linked by springs and coupled to an elastic substrate. The model captures the spatial distribution of traction forces seen in experiments. For cell colonies with strong cell-cell adhesions, the total traction force of the colony measured in experiments is found to scale with the colony's geometrical size. This scaling suggests the emergence of an effective surface tension of magnitude comparable to that measured for non-adherent, three-dimensional cell aggregates. The physical model supports the scaling and indicates that the surface tension may be controlled by acto-myosin contractility. Supported by the NSF through grant DMR-1004789. This work was done in collaboration with Aaron F. Mertz, Eric R. Dufresne and Valerie Horsley (Yale University) and M. Cristina Marchetti (Syracuse University).

  3. Discover for Yourself: An Optimal Control Model in Insect Colonies

    ERIC Educational Resources Information Center

    Winkel, Brian

    2013-01-01

    We describe the enlightening path of self-discovery afforded to the teacher of undergraduate mathematics. This is demonstrated as we find and develop background material on an application of optimal control theory to model the evolutionary strategy of an insect colony to produce the maximum number of queen or reproducer insects in the colony at…

  4. Resisting the Coloniality of English: A Research Review of Strategies

    ERIC Educational Resources Information Center

    Hsu, Funie

    2017-01-01

    The colonial legacy of English instruction has become especially relevant within the field of TESOL. While it is promising that increasing attention is being paid to the issue of colonialism and its historical and contemporary impact on the teaching of English, educators might be left without a clear sense of how to traverse the precarious path of…

  5. Countering Coloniality in Educational Research: From Ownership to Answerability

    ERIC Educational Resources Information Center

    Patel, Lisa

    2014-01-01

    In this theoretical article, I argue for a relational stance on learning as a way of reckoning with educational research as part of the settler colonial structure of the United States. Because of my geopolitical location to the United States as a settler colony, I begin by contrasting the stances of anticolonial and decolonial. I then analyze the…

  6. 21 CFR 866.2170 - Automated colony counter.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Automated colony counter. 866.2170 Section 866.2170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2170 Automated colony...

  7. 21 CFR 866.2180 - Manual colony counter.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Manual colony counter. 866.2180 Section 866.2180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2180 Manual colony counter...

  8. 21 CFR 866.2180 - Manual colony counter.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Manual colony counter. 866.2180 Section 866.2180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2180 Manual colony counter...

  9. 21 CFR 866.2170 - Automated colony counter.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Automated colony counter. 866.2170 Section 866.2170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2170 Automated colony...

  10. 21 CFR 866.2180 - Manual colony counter.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Manual colony counter. 866.2180 Section 866.2180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2180 Manual colony counter...

  11. 21 CFR 866.2170 - Automated colony counter.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Automated colony counter. 866.2170 Section 866.2170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2170 Automated colony...

  12. Heralding the Other: Sousa, Simulacra, and Settler Colonialism

    ERIC Educational Resources Information Center

    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…

  13. Model Specification Searches Using Ant Colony Optimization Algorithms

    ERIC Educational Resources Information Center

    Marcoulides, George A.; Drezner, Zvi

    2003-01-01

    Ant colony optimization is a recently proposed heuristic procedure inspired by the behavior of real ants. This article applies the procedure to model specification searches in structural equation modeling and reports the results. The results demonstrate the capabilities of ant colony optimization algorithms for conducting automated searches.

  14. Estimating 3-dimensional colony surface area of field corals

    EPA Science Inventory

    Colony surface area is a critical descriptor for biological and physical attributes of reef-building (scleractinian, stony) corals. The three-dimensional (3D) size and structure of corals are directly related to many ecosystem values and functions. Most methods to estimate colony...

  15. Colony differences in termiticide transfer studies, a role for behavior?

    Treesearch

    Thomas Shelton

    2010-01-01

    Donor-recipient termiticide transfer laboratory tests were performed by using destructive sampling with two delayed-action non-repellent (DANR) termiticides against each of three colonies of Reticulitermes flavipes (Kollar). Two of the three colonies showed no response to indoxacarb, but all three showed a response to chlorantraniliprole. These results indicate that...

  16. Education "Reform" in Latino Detroit: Achievement Gap or Colonial Legacy?

    ERIC Educational Resources Information Center

    Gonzales, Sandra M.; Shields, Carolyn M.

    2015-01-01

    Using critical theory and an analysis of missionary reports and documentation describing education in colonial Puerto Rico and Mexico, the authors cross borders and time periods to socially and historically situate Spanish colonial educational methodologies and their contemporary use in one low-income Latino community in urban Detroit, Michigan.…

  17. Discover for Yourself: An Optimal Control Model in Insect Colonies

    ERIC Educational Resources Information Center

    Winkel, Brian

    2013-01-01

    We describe the enlightening path of self-discovery afforded to the teacher of undergraduate mathematics. This is demonstrated as we find and develop background material on an application of optimal control theory to model the evolutionary strategy of an insect colony to produce the maximum number of queen or reproducer insects in the colony at…

  18. Nonrelatives inherit colony resources in a primitive termite

    PubMed Central

    Johns, Philip M.; Howard, Kenneth J.; Breisch, Nancy L.; Rivera, Anahi; Thorne, Barbara L.

    2009-01-01

    The evolution of eusociality, especially how selection would favor sterility or subfertility of most individuals within a highly social colony, is an unresolved paradox. Eusociality evolved independently in diverse taxa, including insects (all ants and termites; some bees, wasps, thrips, and beetles), snapping shrimp, and naked mole rats. Termites have received comparatively less focus than the haplodiploid Hymenoptera (ants, bees, and wasps); however, they are the only diploid group with highly complex colonies and an extraordinary diversity of castes. In this study we staged encounters between unrelated colonies of primitive dampwood termites, Zootermopsis nevadensis, mimicking natural meetings that occur under bark. During encounters, kings and/or queens were killed and surviving members merged into one colony. After encounters, members of both unrelated colonies cooperated as a single social unit. We determined the colony of origin of replacement reproductives that emerged after death of kings and/or queens. Here, we document that replacement reproductives developed from workers in either or both original colonies, inherited the merged resources of the colony, and sometimes interbred. Because this species shares many characteristics with ancestral termites, these findings demonstrate how ecological factors could have promoted the evolution of eusociality by accelerating and enhancing direct fitness opportunities of helper offspring, rendering relatedness favoring kin selection less critical. PMID:19805058

  19. Estimating 3-dimensional colony surface area of field corals

    EPA Science Inventory

    Colony surface area is a critical descriptor for biological and physical attributes of reef-building (scleractinian, stony) corals. The three-dimensional (3D) size and structure of corals are directly related to many ecosystem values and functions. Most methods to estimate colony...

  20. Characterisation of Species and Diversity of Anopheles gambiae Keele Colony

    PubMed Central

    McGeechan, Sion; Inch, Donald; Smart, Graeme; Richterová, Lenka; Mwangi, Jonathan M.

    2016-01-01

    Anopheles gambiae sensu stricto was recently reclassified as two species, An. coluzzii and An. gambiae s.s., in wild-caught mosquitoes, on the basis of the molecular form, denoted M or S, of a marker on the X chromosome. The An. gambiae Keele line is an outbred laboratory colony strain that was developed around 12 years ago by crosses between mosquitoes from 4 existing An. gambiae colonies. Laboratory colonies of mosquitoes often have limited genetic diversity because of small starting populations (founder effect) and subsequent fluctuations in colony size. Here we describe the characterisation of the chromosomal form(s) present in the Keele line, and investigate the diversity present in the colony using microsatellite markers on chromosome 3. We also characterise the large 2La inversion on chromosome 2. The results indicate that only the M-form of the chromosome X marker is present in the Keele colony, which was unexpected given that 3 of the 4 parent colonies were probably S-form. Levels of diversity were relatively high, as indicated by a mean number of microsatellite alleles of 6.25 across 4 microsatellites, in at least 25 mosquitoes. Both karyotypes of the inversion on chromosome 2 (2La/2L+a) were found to be present at approximately equal proportions. The Keele colony has a mixed M- and S-form origin, and in common with the PEST strain, we propose continuing to denote it as an An. gambiae s.s. line. PMID:28033418

  1. Women in Sports and Games in the Colonial Period.

    ERIC Educational Resources Information Center

    Howell, Reet A.

    The physical activities of women in the colonial period in the United States were limited. Social attitudes differed between the northern and southern colonies on appropriate activities for women. In the north it was not considered unseemly for women to participate in ice skating, while in the south women were encouraged to become good…

  2. Colonialism, Education and Rural Buddhist Communities in Bangladesh

    ERIC Educational Resources Information Center

    Barua, Bijoy

    2007-01-01

    This paper will excavate pre-independence (British/Pakistan) and post-independence colonial education interventions into Buddhist culture and education with the view to expose the nature and shape of colonial domination and related Buddhist efforts at cultural and educational decolonization. This will be accomplished by (a) considering a brief…

  3. Heralding the Other: Sousa, Simulacra, and Settler Colonialism

    ERIC Educational Resources Information Center

    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…

  4. The Political Economy of Colonial Education: Mozambique, 1930-1975.

    ERIC Educational Resources Information Center

    Cross, Michael

    1987-01-01

    Under colonial fascism and during the revolutionary period leading to independence, the schooling of the African majority in Mozambique had no direct link with the economy, was more a mechanism of social control than of labor reproduction, and (in contrast to other African colonies) did not produce an African middle class supportive of the…

  5. 21 CFR 866.2170 - Automated colony counter.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Automated colony counter. 866.2170 Section 866.2170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2170 Automated colony...

  6. 21 CFR 866.2180 - Manual colony counter.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Manual colony counter. 866.2180 Section 866.2180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2180 Manual colony counter...

  7. 21 CFR 866.2180 - Manual colony counter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Manual colony counter. 866.2180 Section 866.2180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2180 Manual colony counter...

  8. 21 CFR 866.2170 - Automated colony counter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Automated colony counter. 866.2170 Section 866.2170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2170 Automated colony...

  9. Model Specification Searches Using Ant Colony Optimization Algorithms

    ERIC Educational Resources Information Center

    Marcoulides, George A.; Drezner, Zvi

    2003-01-01

    Ant colony optimization is a recently proposed heuristic procedure inspired by the behavior of real ants. This article applies the procedure to model specification searches in structural equation modeling and reports the results. The results demonstrate the capabilities of ant colony optimization algorithms for conducting automated searches.

  10. Countering Coloniality in Educational Research: From Ownership to Answerability

    ERIC Educational Resources Information Center

    Patel, Lisa

    2014-01-01

    In this theoretical article, I argue for a relational stance on learning as a way of reckoning with educational research as part of the settler colonial structure of the United States. Because of my geopolitical location to the United States as a settler colony, I begin by contrasting the stances of anticolonial and decolonial. I then analyze the…

  11. Application of LASCA technique for monitoring of bacterial colonies growth

    NASA Astrophysics Data System (ADS)

    Ulianova, Onega; Rebeza, Olga; Rebeza, Nadezhda; Ulyanov, Sergey

    2013-02-01

    Methods of s-LASCA and t-LASCA have been adopted to problem of monitoring growth of colonies of bacteria E. coli culture B6. Set-up of LASCA-microscope is developed. Results of experimental investigations of influence of speckled biospeckles on results of monitoring of growth of bacterial colonies have been obtained.

  12. Evaluation of counting error due to colony masking in bioaerosol sampling.

    PubMed

    Chang, C W; Hwang, Y H; Grinshpun, S A; Macher, J M; Willeke, K

    1994-10-01

    Colony counting error due to indistinguishable colony overlap (i.e., masking) was evaluated theoretically and experimentally. A theoretical model to predict colony masking was used to determine colony counting efficiency by Monte Carlo computer simulation of microorganism collection and development into CFU. The computer simulation was verified experimentally by collecting aerosolized Bacillus subtilis spores and examining micro- and macroscopic colonies. Colony counting efficiency decreased (i) with increasing density of collected culturable microorganisms, (ii) with increasing colony size, and (iii) with decreasing ability of an observation system to distinguish adjacent colonies as separate units. Counting efficiency for 2-mm colonies, at optimal resolution, decreased from 98 to 85% when colony density increased from 1 to 10 microorganisms cm-2, in contrast to an efficiency decrease from 90 to 45% for 5-mm colonies. No statistically significant difference (alpha = 0.05) between experimental and theoretical results was found when colony shape was used to estimate the number of individual colonies in a CFU. Experimental colony counts were 1.2 times simulation estimates when colony shape was not considered, because of nonuniformity of actual colony size and the better discrimination ability of the human eye relative to the model. Colony surface densities associated with high counting accuracy were compared with recommended upper plate count limits and found to depend on colony size and an observation system's ability to identify overlapped colonies. Correction factors were developed to estimate the actual number of collected microorganisms from observed colony counts.(ABSTRACT TRUNCATED AT 250 WORDS)

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

    PubMed

    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.

  14. An ant colony algorithm on continuous searching space

    NASA Astrophysics Data System (ADS)

    Xie, Jing; Cai, Chao

    2015-12-01

    Ant colony algorithm is heuristic, bionic and parallel. Because of it is property of positive feedback, parallelism and simplicity to cooperate with other method, it is widely adopted in planning on discrete space. But it is still not good at planning on continuous space. After a basic introduction to the basic ant colony algorithm, we will propose an ant colony algorithm on continuous space. Our method makes use of the following three tricks. We search for the next nodes of the route according to fixed-step to guarantee the continuity of solution. When storing pheromone, it discretizes field of pheromone, clusters states and sums up the values of pheromone of these states. When updating pheromone, it makes good resolutions measured in relative score functions leave more pheromone, so that ant colony algorithm can find a sub-optimal solution in shorter time. The simulated experiment shows that our ant colony algorithm can find sub-optimal solution in relatively shorter time.

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

    PubMed Central

    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

  16. Patterns in Saccharomyces cerevisiae yeast colonies via magnetic resonance imaging.

    PubMed

    Tenório, Rômulo P; Barros, Wilson

    2017-01-23

    We report the use of high-resolution magnetic resonance imaging methods to observe pattern formation in colonies of Saccharomyces cerevisiae. Our results indicate substantial signal loss localized in specific regions of the colony rendering useful imaging contrast. This imaging contrast is recognizable as being due to discontinuities in magnetic susceptibility (χ) between different spatial regions. At the microscopic pixel level, the local variations in the magnetic susceptibility (Δχ) induce a loss in the NMR signal, which was quantified via T2 and T2* maps, permitting estimation of Δχ values for different regions of the colony. Interestingly the typical petal/wrinkling patterns present in the colony have a high degree of correlation with the estimated susceptibility distribution. We conclude that the presence of magnetic susceptibility inclusions, together with their spatial arrangement within the colony, may be a potential cause of the susceptibility distribution and therefore the contrast observed on the images.

  17. Diffusion-limited growth in bacterial colony formation

    NASA Astrophysics Data System (ADS)

    Matsushita, Mitsugu; Fujikawa, Hiroshi

    1990-09-01

    Colonies of bacterial species called Bacillus subtilis have been found to grow two-dimensionally and self-similarly on agar plates through diffusion-limited processes in a nutrient concentration field. We obtained a fractal dimension of the colony patterns of D=1.73±0.02, very close to that of the two-dimensional DLA model, and confirmed the existence of the screening effect of protruding main branches against inner ones in a colony, the repulsion between two neighboring colonies and the tendency to grow toward nutrient. These effects are all characteristic of the pattern formation in a Laplacian field. This finding implies the importance of physical properties of the environment for the morphology of bacterial colonies in general.

  18. Observations on colony formation by the cosmopolitan phytoplankton genus Phaeocystis

    NASA Astrophysics Data System (ADS)

    Verity, Peter G.; Medlin, Linda K.

    2003-12-01

    Few marine phytoplankton have heteromorphic life cycles and also often dominate the ecosystems in which they occur. The class Prymnesiophyceae contains a notable exception: the genus Phaeocystis includes three species that form gelatinous colonies but also occur within their ranges as solitary cells. Phaeocystis antarctica and P. pouchetii are exclusively high latitude taxa, and are notable for regionally tremendous blooms of the colony stage. P. globosa occurs circumglobally, yet its colony blooms primarily are confined to colder waters within its range. Three additional species are warm water forms that have been reported only as solitary cells or loose aggregations that bear little resemblance to the organized colonies of the other taxa. Interpretation of existing data indicates that resource availability (light, temperature and nutrients) by itself is not sufficient to explain this distinction between cold-water colony-forming taxa and warm water solitary cell taxa, nor why colony development in P. globosa is essentially a spatially restricted phenomenon within a much broader geographic range. Colony development by P. globosa in situ has been observed at temperatures ≥20 °C, but only rarely and generally under conditions of seasonally or anthropogenically elevated nutrient supply. Data presented here demonstrate colony development at 20-22 °C in natural plankton communities from oligotrophic waters that were pre-screened through 63 μm mesh (i.e. lacking mesozooplankton and large microzooplankton), but not in unscreened communities containing microzooplankton and >63 μm zooplankton. Reduction of colony proliferation at higher temperatures by mesozooplankton grazing remains as an intriguing possibility that is consistent with available evidence to help explain differences in latitudinal extent of in situ colony development. These data are interpreted within a theoretical framework regarding the potential advantages and disadvantages of the two life cycle

  19. Iridovirus and microsporidian linked to honey bee colony decline.

    PubMed

    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.

  20. Iridovirus and Microsporidian Linked to Honey Bee Colony Decline

    PubMed Central

    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.

    2010-01-01

    Background 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. Methodology/Principal Findings 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. Conclusions/Significance 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

  1. Holotransformations of bacterial colonies and genome cybernetics

    NASA Astrophysics Data System (ADS)

    Ben-Jacob, Eshel; Tenenbaum, Adam; Shochet, Ofer; Avidan, Orna

    1994-01-01

    We present a study of colony transformations during growth of Bacillus subtilis under adverse environmental conditions. It is a continuation of our pilot study of “Adaptive self-organization during growth of bacterial colonies” (Physica A 187 (1992) 378). First we identify and describe the transformations pathway, i.e. the excitation of the branching modes from Bacillus subtilis 168 (grown under diffusion limited conditions) and the phase transformations between the tip-splitting phase (phase T) and the chiral phase (phase C) which belong to the same mode. This pathway shows the evolution of complexity as the bacteria are exposed to adverse growth conditions. We present the morphology diagram of phases T and C as a function of agar concentration and pepton level. As expected, the growth of phase T is ramified (fractal-like or DLA-like) at low pepton level (about 1 g/1) and turns compact at high pepton level (about 10 g/1). The growth of phase C is also ramified at low pepton level and turns denser and finally compact as the pepton level increases. Generally speaking, the colonies develop more complex patterns and higher micro-level organization for more adverse environments. We use the growth velocity as a response function to describe the growth. At low agar concentration (and low pepton level) phase C grows faster than phase T, and for a high agar concentration (about 2%) phase T grows faster. We observe colony transformations between the two phases (phase transformations). They are found to be consistent with the “fastest growing morphology” selection principle adopted from azoic systems. The transformations are always from the slower phase to the faster one. Hence, we observe T→ C transformations at low agar concentrations and C→ T transformations at high agar concentrations. We have observed both localized and extended transformations. Usually, the transformations are localized for more adverse growth conditions, and extended for growth conditions

  2. The Importance of Microbes in Nutrition and Health of Honey Bee Colonies Part-2: Factors Affecting the Microbial Community in Honey Bee Colonies

    USDA-ARS?s Scientific Manuscript database

    Honey bee colonies have innumerable symbiotic bacteria and fungi that are essential to the health of the colony. In the first part of this series, we discussed the importance of microbes in maintaining the health of honey bee colonies. The bacteria, yeasts and molds that live in a healthy colony a...

  3. Reforma Ortografica, Planejamento e Difusao Linguistica: O Caso da Lingua Portuguesa (Orthographic Reform, Planning, and Linguistic Diffusion: The Case of Portuguese).

    ERIC Educational Resources Information Center

    Schmitz, John Robert

    1998-01-01

    Suggests that the Luso-Brazilian Accord is a strategy to spread the Portuguese language in Africa, particularly in the former colonies of Angola, Mozambique, Guinea-Bissau, Cape Verde, and Sao Tome e Principe, and to construct and solidify a community of lusophone nations in geopolitical terms in world affairs. Language planning in these countries…

  4. Reforma Ortografica, Planejamento e Difusao Linguistica: O Caso da Lingua Portuguesa (Orthographic Reform, Planning, and Linguistic Diffusion: The Case of Portuguese).

    ERIC Educational Resources Information Center

    Schmitz, John Robert

    1998-01-01

    Suggests that the Luso-Brazilian Accord is a strategy to spread the Portuguese language in Africa, particularly in the former colonies of Angola, Mozambique, Guinea-Bissau, Cape Verde, and Sao Tome e Principe, and to construct and solidify a community of lusophone nations in geopolitical terms in world affairs. Language planning in these countries…

  5. Artificial bee colony in neuro - Symbolic integration

    NASA Astrophysics Data System (ADS)

    Kasihmuddin, Mohd Shareduwan Mohd; Sathasivam, Saratha; Mansor, Mohd. Asyraf

    2017-08-01

    Swarm intelligence is a research area that models the population of the swarm based on natural computation. Artificial bee colony (ABC) algorithm is a swarm based metaheuristic algorithm introduced by Karaboga to optimize numerical problem. Pattern-SAT is a pattern reconstruction paradigm that utilized 2SAT logical rule in representing the behavior of the desired pattern. The information of the desired pattern in terms of 2SAT logic is embedded to Hopfield neural network (HNN-P2SAT) and the desired pattern is reconstructed during the retrieval phase. Since the performance of HNN-P2SAT in Pattern-SAT deteriorates when the number of 2SAT clause increased, newly improved ABC is used to reduce the computation burden during the learning phase of HNN-P2SAT (HNN-P2SATABC). The aim of this study is to investigate the performance of Pattern-SAT produced by ABC incorporated with HNN-P2SAT and compare it with conventional standalone HNN. The comparison is examined by using Microsoft Visual Basic C++ 2013 software. The detailed comparison in doing Pattern-SAT is discussed based on global Pattern-SAT, ratio of activated clauses and computation time. The result obtained from computer simulation indicates the beneficial features of HNN-P2SATABC in doing Pattern-SAT. This finding is expected to result in a significant implication on the choice of searching method used to do Pattern-SAT.

  6. How can bee colony algorithm serve medicine?

    PubMed

    Salehahmadi, Zeinab; Manafi, Amir

    2014-07-01

    Healthcare professionals usually should make complex decisions with far reaching consequences and associated risks in health care fields. As it was demonstrated in other industries, the ability to drill down into pertinent data to explore knowledge behind the data can greatly facilitate superior, informed decisions to ensue the facts. Nature has always inspired researchers to develop models of solving the problems. Bee colony algorithm (BCA), based on the self-organized behavior of social insects is one of the most popular member of the family of population oriented, nature inspired meta-heuristic swarm intelligence method which has been proved its superiority over some other nature inspired algorithms. The objective of this model was to identify valid novel, potentially useful, and understandable correlations and patterns in existing data. This review employs a thematic analysis of online series of academic papers to outline BCA in medical hive, reducing the response and computational time and optimizing the problems. To illustrate the benefits of this model, the cases of disease diagnose system are presented.

  7. Selective sweeps in growing microbial colonies

    NASA Astrophysics Data System (ADS)

    Korolev, Kirill S.; Müller, Melanie J. I.; Karahan, Nilay; Murray, Andrew W.; Hallatschek, Oskar; Nelson, David R.

    2012-04-01

    Evolutionary experiments with microbes are a powerful tool to study mutations and natural selection. These experiments, however, are often limited to the well-mixed environments of a test tube or a chemostat. Since spatial organization can significantly affect evolutionary dynamics, the need is growing for evolutionary experiments in spatially structured environments. The surface of a Petri dish provides such an environment, but a more detailed understanding of microbial growth on Petri dishes is necessary to interpret such experiments. We formulate a simple deterministic reaction-diffusion model, which successfully predicts the spatial patterns created by two competing species during colony expansion. We also derive the shape of these patterns analytically without relying on microscopic details of the model. In particular, we find that the relative fitness of two microbial strains can be estimated from the logarithmic spirals created by selective sweeps. The theory is tested with strains of the budding yeast Saccharomyces cerevisiae for spatial competitions with different initial conditions and for a range of relative fitnesses. The reaction-diffusion model also connects the microscopic parameters like growth rates and diffusion constants with macroscopic spatial patterns and predicts the relationship between fitness in liquid cultures and on Petri dishes, which we confirmed experimentally. Spatial sector patterns therefore provide an alternative fitness assay to the commonly used liquid culture fitness assays.

  8. Was Fundamental Education Another Form Of Colonialism?

    NASA Astrophysics Data System (ADS)

    Watras, Joseph

    2007-01-01

    A description of the work of Pedro Tamesis Orata provides an opportunity to investigate the conflicts that can occur when educators seek to reduce poverty while trying to respect indigenous cultures. A native of the Philippines, Orata completed his doctoral studies at the Ohio State University in 1927. During US President Franklin Roosevelt's New Deal, he accepted the position of school principal for the US Bureau of Indian Affairs. After World War II, he directed the spread of fundamental education through the United Nations Educational, Scientific and Cultural Organization (UNESCO). In his final years, he returned to the Philippines where he began a movement to spread what were called self-help high schools. In these activities, Orata taught people to follow John Dewey's five steps of thinking while working to improve their standards of living. In the 1970s, educators, such as Paulo Freire, complained that problem-solving methods, similar to those Orata favored, reinforced the oppressive aspects of formerly colonial societies. While Freire may have been overly critical, conflicts among cultural orientations appear to be unavoidable. The hope behind this investigation is that the difficulties can be reduced when people understand the different forces that persist.

  9. A View of Future Human Colonies on Mars

    NASA Astrophysics Data System (ADS)

    Gustafson, Robert J.; Rice, Eric E.; Gramer, Daniel J.; White, Brant C.

    2003-01-01

    In a recent feasibility study, ORBITEC conceptualized systems and an evolving architecture for producing and utilizing Mars-based in-situ resources utilization (ISRU) propellant combinations. The propellants will be used to support the propulsion and power systems for ground and flight vehicles that would be part of Mars exploration and colonization. The key aspect of the study was to show the benefits of ISRU, develop an analysis methodology, as well as provide some guidance to future propellant system choices based upon what is known today about Mars. The study time frame included an early unmanned and manned exploration period (now to 2040) and a colonization period that occurs from 2040 to 2090. As part of this feasibility study, ORBITEC developed two different Mars colonization scenarios, namely a low case that ends with a 100-person colony and a high case that ends with a 10.000-person colony. A population growth model, mission traffic model, and infrastructure model was developed for each scenario to better understand the requirements of future Mars colonies. This paper outlines the characteristics of the Mars colonies that ORBITEC envisions under both colonization scenarios. This includes a discussion of the flow of people and materials between the Earth and Mars, the infrastructure requirements of the colonies, potential colony configurations, and the mission requirements of the colonies.

  10. Between stigmatisation and regulation: prostitution in colonial Northern Vietnam.

    PubMed

    Tracol-Huynh, Isabelle

    2010-08-01

    Colonisation was a masculine adventure which took place in a distorted world full of 'welcoming' native women. The colonial encounter therefore was both racial and gendered: boundaries between European men and Vietnamese women were obvious. On the other hand the intimacy that resulted from this encounter blurred the racial boundaries that were the foundation of the colonial order. These boundaries had to be redrawn or sharpened. Focusing on French colonial northern Vietnam (Tonkin) this paper examines how the whole colonial encounter was embodied in the sexual encounter between European men and native women and how prostitution was an integral part of the colonial order. This analysis of the regulation of prostitution and its ambivalence reveals that the definition of prostitution and its treatment by the French colonial authorities was political, racial and therefore connected to a specific period. The political definition of prostitution in today's Vietnam is different from the colonial one. This shift reveals that prostitution is a pertinent vantage point from which one can study how a society apprehends itself and its own future.

  11. Real-Time Screening of Biocatalysts in Live Bacterial Colonies.

    PubMed

    Yan, Cunyu; Parmeggiani, Fabio; Jones, Emrys A; Claude, Emmanuelle; Hussain, Shaneela A; Turner, Nicholas J; Flitsch, Sabine L; Barran, Perdita E

    2017-02-01

    Screening of bacterial colonies to identify new biocatalytic activities is a widely adopted tool in biotechnology, but is constrained by the requirements for colorimetric or tag-based detection methods. Herein we report a label-free screening platform for biotransformations in live colonies using desorption electrospray ionization coupled with ion mobility mass spectrometry imaging (DiBT-IMMS). The screening method is demonstrated for both ammonia lyases and P450 monooxygenases expressed within live bacterial colonies and is shown to enable multiplexing of enzyme variants and substrate libraries simultaneously.

  12. System design of a near-self-supporting lunar colony.

    NASA Technical Reports Server (NTRS)

    Howell, J. R.; Huang, C. J.

    1972-01-01

    Concepts for expanding a 12-man lunar surface base to a more permanent colony of about 180 persons are studied. Guidelines for the colony design are that the colony must perform a useful function, and that design should maximize use of lunar materials and minimize requirements of resupply from the earth. The first use of lunar materials should be for oxygen production, to achieve which large electrical or thermal power inputs are necessary. Some of the efforts which should be directed toward food and plant growth are considered, and those factors from life support and waste control which bear further study are examined. Aspects of power generation, mining, and construction are discussed.

  13. System design of a near-self-supporting lunar colony.

    NASA Technical Reports Server (NTRS)

    Howell, J. R.; Huang, C. J.

    1972-01-01

    Concepts for expanding a 12-man lunar surface base to a more permanent colony of about 180 persons are studied. Guidelines for the colony design are that the colony must perform a useful function, and that design should maximize use of lunar materials and minimize requirements of resupply from the earth. The first use of lunar materials should be for oxygen production, to achieve which large electrical or thermal power inputs are necessary. Some of the efforts which should be directed toward food and plant growth are considered, and those factors from life support and waste control which bear further study are examined. Aspects of power generation, mining, and construction are discussed.

  14. Evolution of medical education in India: The impact of colonialism

    PubMed Central

    Anshu; Supe, A

    2016-01-01

    The cross-cultural exchanges between the people of India and their colonial rulers provides a fascinating insight into how these encounters shaped medicine and medical education in India. This article traces the history of how Indian medicine was transformed in the backdrop of colonialism and hegemony. It goes on to show how six decades after independence, we have have still been unable to convincingly shrug off the colonial yoke. India needs to work out a national medical curriculum which caters to our country's needs. A symbiotic relationship needs to be developed between the indigenous and allopathic systems of medicine. PMID:27763484

  15. Solving Integer Programming Problems by Using Artificial Bee Colony Algorithm

    NASA Astrophysics Data System (ADS)

    Akay, Bahriye; Karaboga, Dervis

    This paper presents a study that applies the Artificial Bee Colony algorithm to integer programming problems and compares its performance with those of Particle Swarm Optimization algorithm variants and Branch and Bound technique presented to the literature. In order to cope with integer programming problems, in neighbour solution production unit, solutions are truncated to the nearest integer values. The experimental results show that Artificial Bee Colony algorithm can handle integer programming problems efficiently and Artificial Bee Colony algorithm can be considered to be very robust by the statistics calculated such as mean, median, standard deviation.

  16. The La Parguera, Puerto Rico colony: establishment and early studies.

    PubMed

    Vandenbergh, J G

    1989-04-01

    Two islands off the southwest coast of Puerto Rico, La Cueva and Guayacan, were populated with monkeys derived from the Cayo Santiago colony and new imports from India during 1962-1963. This colony became known as the La Parguera Colony due to its proximity to the fishing village of La Parguera. Initial work on the island focused on studies of group formation and dynamics. Later, attention turned to field experiments on the interaction of behavior and hormones in coordinating reproduction and a number of other behavioral studies.

  17. Evolution of medical education in India: The impact of colonialism.

    PubMed

    Supe, A

    2016-09-21

    The cross-cultural exchanges between the people of India and their colonial rulers provides a fascinating insight into how these encounters shaped medicine and medical education in India. This article traces the history of how Indian medicine was transformed in the backdrop of colonialism and hegemony. It goes on to show how six decades after independence, we have have still been unable to convincingly shrug off the colonial yoke. India needs to work out a national medical curriculum which caters to our country's needs. A symbiotic relationship needs to be developed between the indigenous and allopathic systems of medicine.

  18. Evolution of medical education in India: The impact of colonialism.

    PubMed

    Supe, A

    2016-01-01

    The cross-cultural exchanges between the people of India and their colonial rulers provides a fascinating insight into how these encounters shaped medicine and medical education in India. This article traces the history of how Indian medicine was transformed in the backdrop of colonialism and hegemony. It goes on to show how six decades after independence, we have have still been unable to convincingly shrug off the colonial yoke. India needs to work out a national medical curriculum which caters to our country's needs. A symbiotic relationship needs to be developed between the indigenous and allopathic systems of medicine.

  19. Metatranscriptomic analyses of honey bee colonies

    PubMed Central

    Tozkar, Cansu Ö.; Kence, Meral; Kence, Aykut; Huang, Qiang; Evans, Jay D.

    2015-01-01

    Honey bees face numerous biotic threats from viruses to bacteria, fungi, protists, and mites. Here we describe a thorough analysis of microbes harbored by worker honey bees collected from field colonies in geographically distinct regions of Turkey. Turkey is one of the World's most important centers of apiculture, harboring five subspecies of Apis mellifera L., approximately 20% of the honey bee subspecies in the world. We use deep ILLUMINA-based RNA sequencing to capture RNA species for the honey bee and a sampling of all non-endogenous species carried by bees. After trimming and mapping these reads to the honey bee genome, approximately 10% of the sequences (9–10 million reads per library) remained. These were then mapped to a curated set of public sequences containing ca. Sixty megabase-pairs of sequence representing known microbial species associated with honey bees. Levels of key honey bee pathogens were confirmed using quantitative PCR screens. We contrast microbial matches across different sites in Turkey, showing new country recordings of Lake Sinai virus, two Spiroplasma bacterium species, symbionts Candidatus Schmidhempelia bombi, Frischella perrara, Snodgrassella alvi, Gilliamella apicola, Lactobacillus spp.), neogregarines, and a trypanosome species. By using metagenomic analysis, this study also reveals deep molecular evidence for the presence of bacterial pathogens (Melissococcus plutonius, Paenibacillus larvae), Varroa destructor-1 virus, Sacbrood virus, and fungi. Despite this effort we did not detect KBV, SBPV, Tobacco ringspot virus, VdMLV (Varroa Macula like virus), Acarapis spp., Tropilaeleps spp. and Apocephalus (phorid fly). We discuss possible impacts of management practices and honey bee subspecies on microbial retinues. The described workflow and curated microbial database will be generally useful for microbial surveys of healthy and declining honey bees. PMID:25852743

  20. Transits of Venus and Colonial India

    NASA Astrophysics Data System (ADS)

    Kochhar, Rajesh

    2012-09-01

    Astronomical expeditions during the colonial period had a political and national significance also. Measuring the earth and mapping the sky were activities worthy of powerful and power- seeking nations. Such was the sanctity of global astronomical activity that many other agendas could be hidden under it. An early astronomy-related expedition turned out to be extremely beneficial, to botany. The expedition sent by the French Government in 1735 to South America under the leadership of Charles Marie de la Condamine (1701--1774) ostensibly for the measurement of an arc of the meridian at Quito in Ecuador surreptitiously collected data that enabled Linnaeus to describe the genus cinchona in 1742. When the pair of transits of Venus occurred in 1761 and 1769, France and England were engaged in a bitter rivalry for control of India. The observation of the transits became a part of the rivalry. A telescope presented by the British to a South Indian King as a decorative toy was borrowed back for actual use. Scientifically the transit observations were a wash out, but the exercise introduced Europe to details of living Indian tradition of eclipse calculations. More significantly, it led to the institutionalization of modern astronomy in India under the auspices of the English East India Company (1787). The transits of Venus of 1874 and 1882 were important not so much for the study of the events as for initiating systematic photography of the Sun. By this, Britain owned most of the world's sunshine, and was expected to help European solar physicists get data from its vast Empire on a regular basis. This and the then genuinely held belief that a study of the sun would help predict failure of monsoons led to the institutionalization of solar physics studies in India (1899). Of course, when the solar physicists learnt that solar activity did not quite determine rainfall in India, they forgot to inform the Government.

  1. Honey Bee Colonies Remote Monitoring System

    PubMed Central

    Gil-Lebrero, Sergio; Quiles-Latorre, Francisco Javier; Ortiz-López, Manuel; Sánchez-Ruiz, Víctor; Gámiz-López, Victoria; Luna-Rodríguez, Juan Jesús

    2016-01-01

    Bees are very important for terrestrial ecosystems and, above all, for the subsistence of many crops, due to their ability to pollinate flowers. Currently, the honey bee populations are decreasing due to colony collapse disorder (CCD). The reasons for CCD are not fully known, and as a result, it is essential to obtain all possible information on the environmental conditions surrounding the beehives. On the other hand, it is important to carry out such information gathering as non-intrusively as possible to avoid modifying the bees’ work conditions and to obtain more reliable data. We designed a wireless-sensor networks meet these requirements. We designed a remote monitoring system (called WBee) based on a hierarchical three-level model formed by the wireless node, a local data server, and a cloud data server. WBee is a low-cost, fully scalable, easily deployable system with regard to the number and types of sensors and the number of hives and their geographical distribution. WBee saves the data in each of the levels if there are failures in communication. In addition, the nodes include a backup battery, which allows for further data acquisition and storage in the event of a power outage. Unlike other systems that monitor a single point of a hive, the system we present monitors and stores the temperature and relative humidity of the beehive in three different spots. Additionally, the hive is continuously weighed on a weighing scale. Real-time weight measurement is an innovation in wireless beehive—monitoring systems. We designed an adaptation board to facilitate the connection of the sensors to the node. Through the Internet, researchers and beekeepers can access the cloud data server to find out the condition of their hives in real time. PMID:28036061

  2. Honey Bee Colonies Remote Monitoring System.

    PubMed

    Gil-Lebrero, Sergio; Quiles-Latorre, Francisco Javier; Ortiz-López, Manuel; Sánchez-Ruiz, Víctor; Gámiz-López, Victoria; Luna-Rodríguez, Juan Jesús

    2016-12-29

    Bees are very important for terrestrial ecosystems and, above all, for the subsistence of many crops, due to their ability to pollinate flowers. Currently, the honey bee populations are decreasing due to colony collapse disorder (CCD). The reasons for CCD are not fully known, and as a result, it is essential to obtain all possible information on the environmental conditions surrounding the beehives. On the other hand, it is important to carry out such information gathering as non-intrusively as possible to avoid modifying the bees' work conditions and to obtain more reliable data. We designed a wireless-sensor networks meet these requirements. We designed a remote monitoring system (called WBee) based on a hierarchical three-level model formed by the wireless node, a local data server, and a cloud data server. WBee is a low-cost, fully scalable, easily deployable system with regard to the number and types of sensors and the number of hives and their geographical distribution. WBee saves the data in each of the levels if there are failures in communication. In addition, the nodes include a backup battery, which allows for further data acquisition and storage in the event of a power outage. Unlike other systems that monitor a single point of a hive, the system we present monitors and stores the temperature and relative humidity of the beehive in three different spots. Additionally, the hive is continuously weighed on a weighing scale. Real-time weight measurement is an innovation in wireless beehive-monitoring systems. We designed an adaptation board to facilitate the connection of the sensors to the node. Through the Internet, researchers and beekeepers can access the cloud data server to find out the condition of their hives in real time.

  3. Chemotaxis migration and morphogenesis of living colonies.

    PubMed

    Ben Amar, Martine

    2013-06-01

    Development of forms in living organisms is complex and fascinating. Morphogenetic theories that investigate these shapes range from discrete to continuous models, from the variational elasticity to time-dependent fluid approach. Here a mixture model is chosen to describe the mass transport in a morphogenetic gradient: it gives a mathematical description of a mixture involving several constituents in mechanical interactions. This model, which is highly flexible can incorporate many biological processes but also complex interactions between cells as well as between cells and their environment. We use this model to derive a free-boundary problem easier to handle analytically. We solve it in the simplest geometry: an infinite linear front advancing with a constant velocity. In all the cases investigated here as the 3 D diffusion, the increase of mitotic activity at the border, nonlinear laws for the uptake of morphogens or for the mobility coefficient, a planar front exists above a critical threshold for the mobility coefficient but it becomes unstable just above the threshold at long wavelengths due to the existence of a Goldstone mode. This explains why sparsely bacteria exhibit dendritic patterns experimentally in opposition to other colonies such as biofilms and epithelia which are more compact. In the most unstable situation, where all the laws: diffusion, chemotaxis driving and chemoattractant uptake are linear, we show also that the system can recover a dynamic stability. A second threshold for the mobility exists which has a lower value as the ratio between diffusion coefficients decreases. Within the framework of this model where the biomass is treated mainly as a viscous and diffusive fluid, we show that the multiplicity of independent parameters in real biologic experimental set-up may explain varieties of observed patterns.

  4. Metatranscriptomic analyses of honey bee colonies.

    PubMed

    Tozkar, Cansu Ö; Kence, Meral; Kence, Aykut; Huang, Qiang; Evans, Jay D

    2015-01-01

    Honey bees face numerous biotic threats from viruses to bacteria, fungi, protists, and mites. Here we describe a thorough analysis of microbes harbored by worker honey bees collected from field colonies in geographically distinct regions of Turkey. Turkey is one of the World's most important centers of apiculture, harboring five subspecies of Apis mellifera L., approximately 20% of the honey bee subspecies in the world. We use deep ILLUMINA-based RNA sequencing to capture RNA species for the honey bee and a sampling of all non-endogenous species carried by bees. After trimming and mapping these reads to the honey bee genome, approximately 10% of the sequences (9-10 million reads per library) remained. These were then mapped to a curated set of public sequences containing ca. Sixty megabase-pairs of sequence representing known microbial species associated with honey bees. Levels of key honey bee pathogens were confirmed using quantitative PCR screens. We contrast microbial matches across different sites in Turkey, showing new country recordings of Lake Sinai virus, two Spiroplasma bacterium species, symbionts Candidatus Schmidhempelia bombi, Frischella perrara, Snodgrassella alvi, Gilliamella apicola, Lactobacillus spp.), neogregarines, and a trypanosome species. By using metagenomic analysis, this study also reveals deep molecular evidence for the presence of bacterial pathogens (Melissococcus plutonius, Paenibacillus larvae), Varroa destructor-1 virus, Sacbrood virus, and fungi. Despite this effort we did not detect KBV, SBPV, Tobacco ringspot virus, VdMLV (Varroa Macula like virus), Acarapis spp., Tropilaeleps spp. and Apocephalus (phorid fly). We discuss possible impacts of management practices and honey bee subspecies on microbial retinues. The described workflow and curated microbial database will be generally useful for microbial surveys of healthy and declining honey bees.

  5. Hindu Responses to Darwinism: Assimilation and Rejection in a Colonial and Post-Colonial Context

    NASA Astrophysics Data System (ADS)

    MacKenzie Brown, C.

    2010-06-01

    Hindu responses to Darwinism, like Christian, have run the gamut from outright rejection to fairly robust but limited accommodations of the Darwinian perspective. Despite certain features of Hindu thought such as the enormous time-scales of traditional cosmogonies that may suggest considerable affinity with modern notions of organic evolution, more often than not traditional assumptions have worked against deep engagement with Darwinism, allowing only for superficial assimilation at best. Three fundamental factors have affected Hindu responses to Darwinism: the great diversity within the tradition spanning evolutionist and creationist perspectives, the encounter with Darwinism in the late nineteenth century as part of an alien culture, and the fact that this encounter occurred within a colonial context. This essay explores the complex interactions of these three factors, beginning with the diversity within the ancient and classical cosmological traditions, followed by consideration of colonial developments and the emergence of four representative Hindu approaches to Darwinism: Modern Vedic Evolutionism, Anthropic Vedic Evolutionism, Reactionary Vedic Evolutionism, and Modern Vedic Creationism. The essay concludes by discussing various epistemological issues in the attempts of modern Hindu apologists to legitimize Vedic world views. These issues include the appeal to modern science to confirm traditional ideals and values, while simultaneously subordinating scientific method to spiritual means of knowledge, or rejecting scientific methodology with its inbuilt skepticism entirely.

  6. Global energy gradients and size in colonial organisms: worker mass and worker number in ant colonies.

    PubMed

    Kaspari, Michael

    2005-04-05

    Body mass shapes processes from cell metabolism to community dynamics. Little is known, however, about how the average body mass of individuals varies among ecological communities. Ants alter colony mass by independently changing worker mass and/or worker number. In a survey of 49 ecosystems from tundra to tropical rainforest, average worker mass and worker number were uncorrelated (r(s) = 0.2, P > 0.14) and varied 100-fold. Data supported the hypothesis that higher mean monthly temperatures, T, reduce worker mass by increasing metabolic costs during worker development. In contrast, worker number was unimodal over a 1,000-fold gradient of net primary productivity (NPP, g of carbon per m2 per yr), a measure of organic carbon available to consumers. At the lowest levels of NPP colonies appeared to be carbon-limited; above 60 g of carbon per m2 per yr average worker number decreased to a global low. This decline in worker number with increasing NPP supports the hypothesis that abundant carbon ameliorates the Achilles heel of small taxa in competition with large taxa: their relatively high metabolic demands. Higher predation rates in resource-rich environments may also play a role in limiting worker number. In all, about half the global variation in worker mass and number was accounted for by gradients of NPP and T. Changes in global temperature and rainfall may thus mold gradients of ectotherm size, with consequences for the structure and function of the ecosystems.

  7. Formation of complex bacterial colonies via self-generated vortices

    NASA Astrophysics Data System (ADS)

    Czirók, András; Ben-Jacob, Eshel; Cohen, Inon; Vicsek, Tamás

    1996-08-01

    Depending on the environmental conditions bacterial colonies growing on agar surfaces can exhibit complex colony formation and various types of collective motion. Experimental results are presented concerning the hydrodynamics (vortices, migration of bacteria in clusters) and colony formation of a morphotype of Bacillus subtilis. Some of these features are not specific to this morphotype but also have been observed in several other bacterial strains, suggesting the presence of universal effects. A simple model of self-propelled particles is proposed, which is capable of describing the hydrodynamics on the intermediate level, including the experimentally observed rotating disks of bacteria. The colony formation is captured by a complex generic model taking into account nutrient diffusion, reproduction, and sporulation of bacteria, extracellular slime deposition, chemoregulation, and inhomogeneous population. Our model also sheds light on some possible biological benefits of this ``multicellular behavior.''

  8. Honeybee colony collapse due to Nosema ceranae in professional apiaries.

    PubMed

    Higes, Mariano; Martín-Hernández, Raquel; Garrido-Bailón, Encarna; González-Porto, Amelia V; García-Palencia, Pilar; Meana, Aranzazu; Del Nozal, María J; Mayo, R; Bernal, José L

    2009-04-01

    Honeybee colony collapse is a sanitary and ecological worldwide problem. The features of this syndrome are an unexplained disappearance of adult bees, a lack of brood attention, reduced colony strength, and heavy winter mortality without any previous evident pathological disturbances. To date there has not been a consensus about its origins. This report describes the clinical features of two professional bee-keepers affecting by this syndrome. Anamnesis, clinical examination and analyses support that the depopulation in both cases was due to the infection by Nosema ceranae (Microsporidia), an emerging pathogen of Apis mellifera. No other significant pathogens or pesticides (neonicotinoids) were detected and the bees had not been foraging in corn or sunflower crops. The treatment with fumagillin avoided the loss of surviving weak colonies. This is the first case report of honeybee colony collapse due to N. ceranae in professional apiaries in field conditions reported worldwide.

  9. Yeast biofilm colony as an orchestrated multicellular organism.

    PubMed

    Sťovíček, Vratislav; Váchová, Libuše; Palková, Zdena

    2012-03-01

    Although still often considered as simple unicellular organisms, in natural settings yeast cells tend to organize into intricate multicellular communities. Due to specific mechanisms only feasible at the population level, their capacity for social behavior is advantageous for their survival in a harmful environment. Feral Saccharomyces cerevisiae strains form complex structured colonies, which display many properties typical of natural biofilms causing (among others) serious infections in the human body. In our recent paper, we looked inside a growing colony using two-photon confocal microscopy. This allowed us to elucidate its three-dimensional colony architecture and some mechanisms responsible for community protection. Moreover, we showed how particular protective mechanisms complement each other during colony development and how each of them contributes to its defense against attacks from the environment. Our findings broaden current understanding of microbial multicellularity in general and also shed new light on the enormous resistance of yeast biofilms.

  10. Revisiting the effect of colonial institutions on comparative economic development.

    PubMed

    Assenova, Valentina A; Regele, Matthew

    2017-01-01

    European settler mortality has been proposed as an instrument to predict the causal effect of colonial institutions on differences in economic development. We examine the relationship between mortality, temperature, and economic development in former European colonies in Asia, Africa, and the Americas. We find that (i) European settler mortality rates increased with regional temperatures and (ii) economic output decreased with regional temperatures. Conditioning on the continent of settlement and accounting for colonies that were not independent as of 1900 undermines the causal effect of colonial institutions on comparative economic development. Our findings run counter to the institutions hypothesis of economic development, showing instead that geography affected both historic mortality rates and present-day economic output.

  11. Pre-colonial Ethnic Institutions and Contemporary African Development.

    PubMed

    Michalopoulos, Stelios; Papaioannou, Elias

    2013-01-01

    We investigate the role of deeply-rooted pre-colonial ethnic institutions in shaping comparative regional development within African countries. We combine information on the spatial distribution of ethnicities before colonization with regional variation in contemporary economic performance, as proxied by satellite images of light density at night. We document a strong association between pre-colonial ethnic political centralization and regional development. This pattern is not driven by differences in local geographic features or by other observable ethnic-specific cultural and economic variables. The strong positive association between pre-colonial political complexity and contemporary development obtains also within pairs of adjacent ethnic homelands with different legacies of pre-colonial political institutions.

  12. Pre-colonial Ethnic Institutions and Contemporary African Development*

    PubMed Central

    Michalopoulos, Stelios; Papaioannou, Elias

    2013-01-01

    We investigate the role of deeply-rooted pre-colonial ethnic institutions in shaping comparative regional development within African countries. We combine information on the spatial distribution of ethnicities before colonization with regional variation in contemporary economic performance, as proxied by satellite images of light density at night. We document a strong association between pre-colonial ethnic political centralization and regional development. This pattern is not driven by differences in local geographic features or by other observable ethnic-specific cultural and economic variables. The strong positive association between pre-colonial political complexity and contemporary development obtains also within pairs of adjacent ethnic homelands with different legacies of pre-colonial political institutions. PMID:25089052

  13. Taverns and Coffee Houses: Adult Educational Institutions In Colonial America.

    ERIC Educational Resources Information Center

    Long, Huey B.

    1981-01-01

    Presents the concept of colonial taverns and coffee houses as adult education institutions. They were of great importance in the development of impressions, opinions, attitudes, and knowledge about agriculture, business, shipping, economics, community and world affairs, and recreation. (CT)

  14. A non-policing honey bee colony (Apis mellifera capensis)

    NASA Astrophysics Data System (ADS)

    Beekman, Madeleine; Good, Gregory; Allsopp, Mike; Radloff, Sarah; Pirk, Chris; Ratnieks, Francis

    2002-09-01

    In the Cape honey bee Apis mellifera capensis, workers lay female eggs without mating by thelytokous parthenogenesis. As a result, workers are as related to worker-laid eggs as they are to queen-laid eggs and therefore worker policing is expected to be lower, or even absent. This was tested by transferring worker- and queen-laid eggs into three queenright A. m. capensis discriminator colonies and monitoring their removal. Our results show that worker policing is variable in A. m. capensis and that in one colony worker-laid eggs were not removed. This is the first report of a non-policing queenright honey bee colony. DNA microsatellite and morphometric analysis suggests that the racial composition of the three discriminator colonies was different. The variation in policing rates could be explained by differences in degrees of hybridisation between A. m. capensis and A. m. scutellata, although a larger survey is needed to confirm this.

  15. A non-policing honey bee colony (Apis mellifera capensis).

    PubMed

    Beekman, Madeleine; Good, Gregory; Allsopp, Mike H; Radloff, Sarah; Pirk, Chris W W; Ratnieks, Francis L W

    2002-10-01

    In the Cape honey bee Apis mellifera capensis, workers lay female eggs without mating by thelytokous parthenogenesis. As a result, workers are as related to worker-laid eggs as they are to queen-laid eggs and therefore worker policing is expected to be lower, or even absent. This was tested by transferring worker- and queen-laid eggs into three queenright A. m. capensis discriminator colonies and monitoring their removal. Our results show that worker policing is variable in A. m. capensis and that in one colony worker-laid eggs were not removed. This is the first report of a non-policing queenright honey bee colony. DNA microsatellite and morphometric analysis suggests that the racial composition of the three discriminator colonies was different. The variation in policing rates could be explained by differences in degrees of hybridisation between A. m. capensis and A. m. scutellata, although a larger survey is needed to confirm this.

  16. The Challenge to USAFRICOM from Africa’s Colonial Past

    DTIC Science & Technology

    2010-03-18

    colonialism in Africa has created a legacy of distrust that will hamper U.S. efforts to engage effectively on the continent. The paper will analyze the...paper is to show that long term colonialism in Africa has created a legacy of distrust that will hamper U.S. efforts to engage effectively on the...This proved difficult because of the Europeans’ effective use of a divide and conquer strategy in their approach to colonialism—separation along

  17. Remarks of Elliptic Curves Derived from Ant Colony Routing

    NASA Astrophysics Data System (ADS)

    Jung, Sangsu; Kim, Daeyeoul; Singh, Dhananjay

    2011-09-01

    We deal with an ant colony based routing model for wireless multi-hop networks. Our model adopts an elliptic curve equation, which is beneficial to design pheromone dynamics for load balancing and packet delivery robustness. Due to the attribute of an elliptic curve equation, our model prevents the over-utilization of a specific node, distinctively from conventional ant colony based schemes. Numerical simulations exhibit the characteristics of our model with respect to various parameters.

  18. Detection of hemolytic Listeria monocytogenes by using DNA colony hybridization

    SciTech Connect

    Datta, A.R.; Wentz, B.A.; Hill, W.E.

    1987-09-01

    A fragment of about 500 base pairs of the beta-hemolysin gene from Listeria monocytogenes was used to screen different bacterial strains by DNA colony hybridization. The cells in the colonies were lysed by microwaves in the presence of sodium hydroxide. Of 52 different strains of Listeria species screened, only the DNA from beta-hemolytic (CAMP-positive) strains of L. monocytogenes hybridized with this probe.

  19. Modelling Food and Population Dynamics in Honey Bee Colonies

    PubMed Central

    Khoury, David S.; Barron, Andrew B.; Myerscough, Mary R.

    2013-01-01

    Honey bees (Apis mellifera) are increasingly in demand as pollinators for various key agricultural food crops, but globally honey bee populations are in decline, and honey bee colony failure rates have increased. This scenario highlights a need to understand the conditions in which colonies flourish and in which colonies fail. To aid this investigation we present a compartment model of bee population dynamics to explore how food availability and bee death rates interact to determine colony growth and development. Our model uses simple differential equations to represent the transitions of eggs laid by the queen to brood, then hive bees and finally forager bees, and the process of social inhibition that regulates the rate at which hive bees begin to forage. We assume that food availability can influence both the number of brood successfully reared to adulthood and the rate at which bees transition from hive duties to foraging. The model predicts complex interactions between food availability and forager death rates in shaping colony fate. Low death rates and high food availability results in stable bee populations at equilibrium (with population size strongly determined by forager death rate) but consistently increasing food reserves. At higher death rates food stores in a colony settle at a finite equilibrium reflecting the balance of food collection and food use. When forager death rates exceed a critical threshold the colony fails but residual food remains. Our model presents a simple mathematical framework for exploring the interactions of food and forager mortality on colony fate, and provides the mathematical basis for more involved simulation models of hive performance. PMID:23667418

  20. Modelling food and population dynamics in honey bee colonies.

    PubMed

    Khoury, David S; Barron, Andrew B; Myerscough, Mary R

    2013-01-01

    Honey bees (Apis mellifera) are increasingly in demand as pollinators for various key agricultural food crops, but globally honey bee populations are in decline, and honey bee colony failure rates have increased. This scenario highlights a need to understand the conditions in which colonies flourish and in which colonies fail. To aid this investigation we present a compartment model of bee population dynamics to explore how food availability and bee death rates interact to determine colony growth and development. Our model uses simple differential equations to represent the transitions of eggs laid by the queen to brood, then hive bees and finally forager bees, and the process of social inhibition that regulates the rate at which hive bees begin to forage. We assume that food availability can influence both the number of brood successfully reared to adulthood and the rate at which bees transition from hive duties to foraging. The model predicts complex interactions between food availability and forager death rates in shaping colony fate. Low death rates and high food availability results in stable bee populations at equilibrium (with population size strongly determined by forager death rate) but consistently increasing food reserves. At higher death rates food stores in a colony settle at a finite equilibrium reflecting the balance of food collection and food use. When forager death rates exceed a critical threshold the colony fails but residual food remains. Our model presents a simple mathematical framework for exploring the interactions of food and forager mortality on colony fate, and provides the mathematical basis for more involved simulation models of hive performance.

  1. The adaptive significance of phasic colony cycles in army ants.

    PubMed

    Garnier, Simon; Kronauer, Daniel J C

    2017-09-07

    Army ants are top arthropod predators in tropical forests around the world. The colonies of many army ant species undergo stereotypical behavioral and reproductive cycles, alternating between brood care and reproductive phases. In the brood care phase, colonies contain a cohort of larvae that are synchronized in their development and have to be fed. In the reproductive phase larvae are absent and oviposition takes place. Despite these colony cycles being a striking feature of army ant biology, their adaptive significance is unclear. Here we use a modeling approach to show that cyclic reproduction is favored under conditions where per capita foraging costs decrease with the number of larvae in a colony ("High Cost of Entry" scenario), while continuous reproduction is favored under conditions where per capita foraging costs increase with the number of larvae ("Resource Exhaustion" scenario). We argue that the former scenario specifically applies to army ants, because large raiding parties are required to overpower prey colonies. However, once raiding is successful it provides abundant food for a large cohort of larvae. The latter scenario, on the other hand, will apply to non-army ants, because in those species local resource depletion will force workers to forage over larger distances to feed large larval cohorts. Our model provides a quantitative framework for understanding the adaptive value of phasic colony cycles in ants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Development of bacterial colony phenotyping instrument using reflected scatter light

    NASA Astrophysics Data System (ADS)

    Doh, Iyll-Joon

    Bacterial rapid detection using optical scattering technology (BARDOT) involves in differentiating elastic scattering pattern of bacterial colony. This elastic light scatter technology has shown promising label-free classification rate. However, there is limited success in certain circumstances where either a growth media or a colony has higher opacity. This situation is due to the physical principles of the current BARDOT which mainly relies on optical patterns generated by transmitted signals. Incoming light is obstructed and cannot be transmitted through the dense bacterial colonies, such as Lactobacillus, Yeast, mold and soil bacteria. Moreover, a blood agar, widely used in clinical field, is an example of an opaque media that does not allow light to be transmitted through. Therefore, in this research, a newly designed reflection type scatterometer is presented. The reflection type scatterometer measures the elastic scattering pattern generated by reflected signal. A theoretical model to study the optical pattern characteristic with respect to bacterial colony morphology is presented. Both theoretical and experiment results show good agreement that the size of backward scattering pattern has positive correlation to colony aspect ratio, a colony elevation to diameter ratio. Four pathogenic bacteria on blood agar, Escherichia coli K12, Listeria innocua, Salmonella Typhimurium, and Staphylococcus aureus, are tested and measured with proposed instrument. The measured patterns are analyzed with a classification software, and high classification rate can be achieved.

  3. Theoretical size controls of the giant Phaeocystis globosa colonies

    NASA Astrophysics Data System (ADS)

    Liu, Xiao; Smith, Walker O.; Tang, Kam W.; Doan, Nhu Hai; Nguyen, Ngoc Lam

    2015-06-01

    An unusual characteristic of the cosmopolitan haptophyte Phaeocystis globosa is its ability to form colonies of strikingly large size-up to 3 cm in diameter. The large size and the presence of a mucoid envelope are believed to contribute to the formation of dense blooms in Southeast Asia. We collected colonies of different sizes in shallow coastal waters of Viet Nam and conducted a series of measurements and experiments on individual colonies. Using these empirical data, we developed a simple carbon-based model to predict the growth and maximal size of P. globosa colonies. Our model suggests that growth of a colony from 0.2 cm to 1.4 cm (the maximal size in our samples) would take 16 days. This number, however, is strongly influenced by the maximal photosynthetic rate and other physiological parameters used in the model. The model also returns a specific growth rate of 0.30 d-1 for colonial cells, comparable to satellite estimates, but lower than have been measured for unicellular P. globosa in batch culture at similar temperatures. We attribute this low growth rate to not only the model uncertainties, but factors such as self-shading and diffusive limitation of nutrient uptake.

  4. Characterization of colony morphology variants isolated from Pseudomonas aeruginosa biofilms.

    PubMed

    Kirisits, Mary Jo; Prost, Lynne; Starkey, Melissa; Parsek, Matthew R

    2005-08-01

    In this study, we report the isolation of small, rough, strongly cohesive colony morphology variants from aging Pseudomonas aeruginosa PAO1 biofilms. Similar to many of the P. aeruginosa colony morphology variants previously described in the literature, these variants autoaggregate in liquid culture and hyperadhere to solid surfaces. They also exhibit increased hydrophobicity and reduced motility compared to the wild-type parent strain. Despite the similarities in appearance of our colony morphology variant isolates on solid medium, the isolates showed a range of responses in various phenotypic assays. These variants form biofilms with significant three-dimensional structure and more biomass than the wild-type parent. To further explore the nature of the variants, their transcriptional profiles were evaluated. The variants generally showed increased expression of the psl and pel loci, which have been previously implicated in the adherence of P. aeruginosa to solid surfaces. When a mutation in the psl locus was introduced into a colony morphology variant, the colony morphology was only partially affected, but hyperadherence and autoaggregation were lost. Finally, similar colony morphology variants were found in isolates from cystic fibrosis patients. These variants displayed many of the same characteristics as the laboratory variants, suggesting a link between laboratory and cystic fibrosis biofilms.

  5. Investigating Microbial (Micro)colony Heterogeneity by Vibrational Spectroscopy

    PubMed Central

    Choo-Smith, L.-P.; Maquelin, K.; van Vreeswijk, T.; Bruining, H. A.; Puppels, G. J.; Thi, N. A. Ngo; Kirschner, C.; Naumann, D.; Ami, D.; Villa, A. M.; Orsini, F.; Doglia, S. M.; Lamfarraj, H.; Sockalingum, G. D.; Manfait, M.; Allouch, P.; Endtz, H. P.

    2001-01-01

    Fourier transform infrared and Raman microspectroscopy are currently being developed as new methods for the rapid identification of clinically relevant microorganisms. These methods involve measuring spectra from microcolonies which have been cultured for as little as 6 h, followed by the nonsubjective identification of microorganisms through the use of multivariate statistical analyses. To examine the biological heterogeneity of microorganism growth which is reflected in the spectra, measurements were acquired from various positions within (micro)colonies cultured for 6, 12, and 24 h. The studies reveal that there is little spectral variance in 6-h microcolonies. In contrast, the 12- and 24-h cultures exhibited a significant amount of heterogeneity. Hierarchical cluster analysis of the spectra from the various positions and depths reveals the presence of different layers in the colonies. Further analysis indicates that spectra acquired from the surface of the colonies exhibit higher levels of glycogen than do the deeper layers of the colony. Additionally, the spectra from the deeper layers present with higher RNA levels than the surface layers. Therefore, the 6-h colonies with their limited heterogeneity are more suitable for inclusion in a spectral database to be used for classification purposes. These results also demonstrate that vibrational spectroscopic techniques can be useful tools for studying the nature of colony development and biofilm formation. PMID:11282591

  6. Appearance of colonies of Prototheca on CHROMagar Candida medium.

    PubMed

    Casal, M; Linares, M J; Solís, F; Rodríguez, F C

    1997-01-01

    The microorganisms capable of producing opportunist infections include the yeast-like organisms of the genus Candida, and the unicellular algae of the genus Prototheca, which share common features and can, therefore, lead to confusion. Their colonies are almost identical and they grow in the same culture media used routinely in mycology. CHROMagar Candida is a new chromogenic differential isolation medium that facilitates the presumptive differentiation of some of the most clinically important yeast-like organisms. To our knowledge, the use of CHROMagar Candida with Prototheca spp. has not been reported in the literature. This report describes the growth of 151 strains of Prototheca on CHROMagar Candida compared to the growth of a total of 326 well-characterized yeast organisms of the genera Candida, Cryptococcus, Trichosporon, Geotrichum, and Saccharomyces. It is clinically relevant to note that algae of the genus Prototheca (P. wickerhamii, P. zopfii, and P. stagnora) and of the genus Candida parapsilosis produced similar cream-colored colonies on CHROMagar Candida medium. Based on their growth on CHROMagar, a new species of Candida is described, C. zeylanoides, which has blue-green colonies. The colonies of two species of Trichosporon are also differentiated: the blue-green colonies of T. beigelii and the pink colonies of T. capitatum.

  7. Surplus nectar available for subalpine bumble bee colony growth.

    PubMed

    Elliott, Susan E

    2009-12-01

    Mutualisms may cause coupled population expansion or decline if both partners respond to variation in the other's abundance. Many studies have shown how the abundance of animal mutualists affects plant reproduction, but less is known about how the abundance of plant mutualists affects animal reproduction. Over 2 yr, I compared reproduction of the bumble bee, Bombus appositus, across meadows that varied naturally in flower density, and I compared reproduction between fed colonies and unfed control colonies. Colony reproduction (gyne, worker, and male production) was constant across meadows that varied naturally in flower density. Forager densities per flower did not vary among meadows, and daily nectar depletion was consistently low across meadows, suggesting that bees had ample nectar in all meadows. However, colonies directly fed with supplemental nectar and pollen generally produced over twice as many gynes as control colonies. Feeding did not affect male or worker production. Although colonies may benefit from food supplementation at the nest, it is possible that they may not benefit from additional flowers because they have too few workers to collect extra resources.

  8. Colony fusion in Argentine ants is guided by worker and queen cuticular hydrocarbon profile similarity.

    PubMed

    Vásquez, Gissella M; Schal, Coby; Silverman, Jules

    2009-08-01

    Introduced populations of the Argentine ant, Linepithema humile, have experienced moderate to severe losses of genetic diversity, which may have affected nestmate recognition to various degrees. We hypothesized that cuticular hydrocarbons (CHC) serve as nestmate recognition cues, and facilitate colony fusion of unrelated L. humile colonies that share similar CHC profiles. In this study, we paired six southeastern U.S. L. humile colonies in a 6-month laboratory fusion assay, and determined if worker and queen CHC profile similarity between colonies was associated with colony fusion and intercolony genetic similarity. We also compared worker and queen CHC profiles between fused colony pairs and unpaired controls to determine if worker and queen chemical profiles changed after fusion. We found that colony fusion correlated with the CHC similarity of workers and queens, with the frequency of fusion increasing with greater CHC profile similarity between colonies. Worker and queen CHC profile similarity between colonies also was associated with genetic similarity between colonies. Queen CHC profiles in fused colonies appeared to be a mix of the two colony phenotypes. In contrast, when only one of the paired colonies survived, the CHC profile of the surviving queens did not diverge from that of the colony of origin. Similarly, workers in non-fused colonies maintained their colony-specific CHC, whereas in fused colonies the worker CHC profiles were intermediate between those of the two colonies. These results suggest a role for CHC in regulating interactions among mutually aggressive L. humile colonies, and demonstrate that colony fusion correlates with both genetic and CHC similarities. Further, changes in worker and queen chemical profiles in fused colonies suggest that CHC plasticity may sustain the cohesion of unrelated L. humile colonies that had fused.

  9. Specific Pathogen Free Macaque Colonies: A Review of Principles and Recent Advances for Viral Testing and Colony Management

    PubMed Central

    Yee, JoAnn L.; Vandeford, Thomas H.; Didier, Elizabeth S.; Gray, Stanton; Lewis, Anne; Roberts, Jeffrey; Taylor, Kerry; Bohm, Rudolf P.

    2016-01-01

    Specific Pathogen Free (SPF) macaques provide valuable animal models for biomedical research. In 1989 the National Center for Research Resources (now Office of Research Infrastructure Programs ORIP) of the National Institutes of Health initiated experimental research contracts to establish and maintain SPF colonies. The derivation and maintenance of SPF macaque colonies is a complex undertaking requiring knowledge of the biology of the agents for exclusion and normal physiology and behavior of macaques, application of the latest diagnostic technology, facilities management, and animal husbandry. This review provides information on the biology of the four viral agents targeted for exclusion in ORIP SPF macaque colonies, describes current state-of-the-art viral diagnostic algorithms, presents data from proficiency testing of diagnostic assays between laboratories at institutions participating in the ORIP SPF program, and outlines management strategies for maintaining the integrity of SPF colonies using results of diagnostic testing as a guide to decision making. PMID:26932456

  10. Microbiome of Trichodesmium Colonies from the North Pacific Subtropical Gyre

    PubMed Central

    Gradoville, Mary R.; Crump, Byron C.; Letelier, Ricardo M.; Church, Matthew J.; White, Angelicque E.

    2017-01-01

    Filamentous diazotrophic Cyanobacteria of the genus Trichodesmium, often found in colonial form, provide an important source of new nitrogen to tropical and subtropical marine ecosystems. Colonies are composed of several clades of Trichodesmium in association with a diverse community of bacterial and eukaryotic epibionts. We used high-throughput 16S rRNA and nifH gene sequencing, carbon (C) and dinitrogen (N2) fixation assays, and metagenomics to describe the diversity and functional potential of the microbiome associated with Trichodesmium colonies collected from the North Pacific Subtropical Gyre (NPSG). The 16S rRNA and nifH gene sequences from hand-picked colonies were predominantly (>99%) from Trichodesmium Clade I (i.e., T. thiebautii), which is phylogenetically and ecologically distinct from the Clade III IMS101 isolate used in most laboratory studies. The bacterial epibiont communities were dominated by Bacteroidetes, Alphaproteobacteria, and Gammaproteobacteria, including several taxa with a known preference for surface attachment, and were relatively depleted in the unicellular Cyanobacteria and small photoheterotrophic bacteria that dominate NPSG surface waters. Sequencing the nifH gene (encoding a subcomponent of the nitrogenase enzyme) identified non-Trichodesmium diazotrophs that clustered predominantly among the Cluster III nifH sequence-types that includes putative anaerobic diazotrophs. Trichodesmium colonies may represent an important habitat for these Cluster III diazotrophs, which were relatively rare in the surrounding seawater. Sequence analyses of nifH gene transcripts revealed several cyanobacterial groups, including heterocystous Richelia, associated with the colonies. Both the 16S rRNA and nifH datasets indicated strong differences between Trichodesmium epibionts and picoplankton in the surrounding seawater, and also between the epibionts inhabiting Trichodesmium puff and tuft colony morphologies. Metagenomic and 16S rRNA gene sequence

  11. Colonie Interim Storage Site annual site environmental report for calendar year 1989, Colonie, New York

    SciTech Connect

    Not Available

    1990-05-01

    IN 1984, Congress assigned the cleanup of the National Lead (NL) Industries site in Colonie, New York, to the Department of Energy (DOE) as part of a decontamination research and development project under the 1984 Energy and Water Appropriations Act. DOE then included the site in the Formerly Utilized Sites Remedial Action Program (FUSRAP), an existing DOE program to decontaminate or otherwise control sites where residual radioactive materials remain for the early years of the nation's atomic energy program. DOE instituted an environmental monitoring program at the site in 1984. Results are presented annually in reports such as this. Under FUSRAP, the first environmental monitoring report for this site presented data for calendar year 1984. This report presents the findings of the environmental monitoring program conducted during calendar year 1989. 16 refs., 17 figs., 14 tabs.

  12. The production of diaspora: Algerian emigration from colonialism to neo-colonialism (1840-1970).

    PubMed

    Samers, M

    1997-01-01

    "This paper is part of a larger project investigating the production and regulation of North African immigrants in the greater Paris automobile industry. Its aims are twofold. First, to reverse the emphasis placed on immigrants in the receiving countries and to (re-)explore the historical production of Algerian emigration into metropolitan industry, more specifically within the automobile industry....Second, in adopting an ¿articulation of modes of production' (AMOP) narrative as an alternative to other Eurocentric approaches, the first part of this paper emphasizes the contradictory layering of various modes which have produced an Algerian colonial diaspora. The latter half of the paper argues that the history of post-independence Algeria confirms that emigration was reinforced through a complex neocolonial relationship during a period of rapid acceleration of Algerian migration to France."

  13. Spread of plague among black-tailed prairie dogs is associated with colony spatial characteristics

    USGS Publications Warehouse

    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.

  14. A metagenomic survey of microbes in honey bee colony collapse disorder

    USDA-ARS?s Scientific Manuscript database

    In Colony Collapse Disorder (CCD), honey bee colonies inexplicably lose all of their workers. CCD has resulted in a loss of 50-90% of colonies in beekeeping operations across the United States. The observation that irradiated combs from affected colonies can be repopulated with naïve bees suggests a...

  15. Social interactions in the central nest of Coptotermes formosanus juvenile colonies

    USDA-ARS?s Scientific Manuscript database

    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...

  16. Social interactions in the central nest of Coptotermes formosanus juvenile colonies

    USDA-ARS?s Scientific Manuscript database

    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 ...

  17. Variation in Symbiodinium ITS2 Sequence Assemblages among Coral Colonies

    PubMed Central

    Stat, Michael; Bird, Christopher E.; Pochon, Xavier; Chasqui, Luis; Chauka, Leonard J.; Concepcion, Gregory T.; Logan, Dan; Takabayashi, Misaki; Toonen, Robert J.; Gates, Ruth D.

    2011-01-01

    Endosymbiotic dinoflagellates in the genus Symbiodinium are fundamentally important to the biology of scleractinian corals, as well as to a variety of other marine organisms. The genus Symbiodinium is genetically and functionally diverse and the taxonomic nature of the union between Symbiodinium and corals is implicated as a key trait determining the environmental tolerance of the symbiosis. Surprisingly, the question of how Symbiodinium diversity partitions within a species across spatial scales of meters to kilometers has received little attention, but is important to understanding the intrinsic biological scope of a given coral population and adaptations to the local environment. Here we address this gap by describing the Symbiodinium ITS2 sequence assemblages recovered from colonies of the reef building coral Montipora capitata sampled across Kāne'ohe Bay, Hawai'i. A total of 52 corals were sampled in a nested design of Coral Colony(Site(Region)) reflecting spatial scales of meters to kilometers. A diversity of Symbiodinium ITS2 sequences was recovered with the majority of variance partitioning at the level of the Coral Colony. To confirm this result, the Symbiodinium ITS2 sequence diversity in six M. capitata colonies were analyzed in much greater depth with 35 to 55 clones per colony. The ITS2 sequences and quantitative composition recovered from these colonies varied significantly, indicating that each coral hosted a different assemblage of Symbiodinium. The diversity of Symbiodinium ITS2 sequence assemblages retrieved from individual colonies of M. capitata here highlights the problems inherent in interpreting multi-copy and intra-genomically variable molecular markers, and serves as a context for discussing the utility and biological relevance of assigning species names based on Symbiodinium ITS2 genotyping. PMID:21246044

  18. Variation in Symbiodinium ITS2 sequence assemblages among coral colonies.

    PubMed

    Stat, Michael; Bird, Christopher E; Pochon, Xavier; Chasqui, Luis; Chauka, Leonard J; Concepcion, Gregory T; Logan, Dan; Takabayashi, Misaki; Toonen, Robert J; Gates, Ruth D

    2011-01-05

    Endosymbiotic dinoflagellates in the genus Symbiodinium are fundamentally important to the biology of scleractinian corals, as well as to a variety of other marine organisms. The genus Symbiodinium is genetically and functionally diverse and the taxonomic nature of the union between Symbiodinium and corals is implicated as a key trait determining the environmental tolerance of the symbiosis. Surprisingly, the question of how Symbiodinium diversity partitions within a species across spatial scales of meters to kilometers has received little attention, but is important to understanding the intrinsic biological scope of a given coral population and adaptations to the local environment. Here we address this gap by describing the Symbiodinium ITS2 sequence assemblages recovered from colonies of the reef building coral Montipora capitata sampled across Kāne'ohe Bay, Hawai'i. A total of 52 corals were sampled in a nested design of Coral Colony(Site(Region)) reflecting spatial scales of meters to kilometers. A diversity of Symbiodinium ITS2 sequences was recovered with the majority of variance partitioning at the level of the Coral Colony. To confirm this result, the Symbiodinium ITS2 sequence diversity in six M. capitata colonies were analyzed in much greater depth with 35 to 55 clones per colony. The ITS2 sequences and quantitative composition recovered from these colonies varied significantly, indicating that each coral hosted a different assemblage of Symbiodinium. The diversity of Symbiodinium ITS2 sequence assemblages retrieved from individual colonies of M. capitata here highlights the problems inherent in interpreting multi-copy and intra-genomically variable molecular markers, and serves as a context for discussing the utility and biological relevance of assigning species names based on Symbiodinium ITS2 genotyping.

  19. Changes in the patterning of a hydroid colony.

    PubMed

    Kosevich, Igor A

    2006-01-01

    It is a widely held view that colonial hydroids (Cnidaria, Hydroidomedusae) are formed on the basis of a repetition of uniform elements. The dominant opinion is that the equal spatial organisation of the colony exists during all stages of its development except the primary polyp, which develops from the settled larva. However, the complex structure and large dimensions of shoots in certain thecate species (subcl. Leptomedusae) suggest that the organisation of the primary shoot differs strongly from that of established colonies. The present study based on a thorough collection and examination of the collected material allowed to describe the entire sequence of the colony ontogeny in Hydrallmania falcata (Sertulariidae). The established shoots of this species are characterised by relatively large size, spiral arrangement of pinnate branches over the shoot stem, and hydranths arranged in one row along the upper side of branches. We showed that the primary shoot developing from the larva has much smaller dimensions and an alternate arrangement of hydranths. During further colony development the shoot organisation undergoes a gradual transformation ending with the emergence of large shoots with 'characteristic' species-specific features. The discovered sequence of changes in shoot patterning shows certain correlations with alterations of the growing tip dimensions. The dimensions of the growing tip seem to determine the patterning in accordance with the particular spatial location of the tip. This finding implies the necessity of a detailed reinvestigation of the entire colony development in thecate hydroids, which would make a significant contribution to the understanding of the morphogenetic evolution and patterning mechanisms within this group of colonial organisms.

  20. Infestation by Pyemotes tritici (Acari, Pyemotidae) causes death of stingless bee colonies (Hymenoptera: Meliponina).

    PubMed

    Menezes, C; Coletto-Silva, A; Gazeta, G S; Kerr, W E

    2009-01-01

    We report the infestation of stingless bee nests by the mite Pyemotes tritici, which killed four colonies of Tetragonisca angustula and one colony of Frieseomelitta varia in Brazil. The first infected colony, a colony of T. angustula, came from an area between Uberlândia and Araguari, Minas Gerais. The transfer of the mites to the other colonies occurred through the transfer of infected combs and subsequent manipulations. Other colonies in the same meliponary, which had not been manipulated, were not infected. The infestation was terminated by isolating the dead colonies from the meliponary.

  1. California gull chicks raised near colony edges have elevated stress levels

    USGS Publications Warehouse

    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.

  2. Toward a post-colonial feminist methodology in nursing research: exploring the convergence of post-colonial and black feminist scholarship.

    PubMed

    Anderson, Joan M; McCann, Elizabeth Kenny

    2002-01-01

    In this paper, Joan M Anderson explores post-colonial feminist scholarship, generated through the convergence of black feminist and post-colonial scholarship, and examines its use as a theory and methodology for nursing scholarship.

  3. Colony size predicts division of labour in attine ants

    PubMed Central

    Ferguson-Gow, Henry; Sumner, Seirian; Bourke, Andrew F. G.; Jones, Kate E.

    2014-01-01

    Division of labour is central to the ecological success of eusocial insects, yet the evolutionary factors driving increases in complexity in division of labour are little known. The size–complexity hypothesis proposes that, as larger colonies evolve, both non-reproductive and reproductive division of labour become more complex as workers and queens act to maximize inclusive fitness. Using a statistically robust phylogenetic comparative analysis of social and environmental traits of species within the ant tribe Attini, we show that colony size is positively related to both non-reproductive (worker size variation) and reproductive (queen–worker dimorphism) division of labour. The results also suggested that colony size acts on non-reproductive and reproductive division of labour in different ways. Environmental factors, including measures of variation in temperature and precipitation, had no significant effects on any division of labour measure or colony size. Overall, these results support the size–complexity hypothesis for the evolution of social complexity and division of labour in eusocial insects. Determining the evolutionary drivers of colony size may help contribute to our understanding of the evolution of social complexity. PMID:25165765

  4. Ant Colonies Prefer Infected over Uninfected Nest Sites

    PubMed Central

    Pontieri, Luigi; Vojvodic, Svjetlana; Graham, Riley; Pedersen, Jes Søe; Linksvayer, Timothy A.

    2014-01-01

    During colony relocation, the selection of a new nest involves exploration and assessment of potential sites followed by colony movement on the basis of a collective decision making process. Hygiene and pathogen load of the potential nest sites are factors worker scouts might evaluate, given the high risk of epidemics in group-living animals. Choosing nest sites free of pathogens is hypothesized to be highly efficient in invasive ants as each of their introduced populations is often an open network of nests exchanging individuals (unicolonial) with frequent relocation into new nest sites and low genetic diversity, likely making these species particularly vulnerable to parasites and diseases. We investigated the nest site preference of the invasive pharaoh ant, Monomorium pharaonis, through binary choice tests between three nest types: nests containing dead nestmates overgrown with sporulating mycelium of the entomopathogenic fungus Metarhizium brunneum (infected nests), nests containing nestmates killed by freezing (uninfected nests), and empty nests. In contrast to the expectation pharaoh ant colonies preferentially (84%) moved into the infected nest when presented with the choice of an infected and an uninfected nest. The ants had an intermediate preference for empty nests. Pharaoh ants display an overall preference for infected nests during colony relocation. While we cannot rule out that the ants are actually manipulated by the pathogen, we propose that this preference might be an adaptive strategy by the host to “immunize” the colony against future exposure to the same pathogenic fungus. PMID:25372856

  5. Active mechanics and geometry of adherent cells and cell colonies

    NASA Astrophysics Data System (ADS)

    Banerjee, Shiladitya

    2014-03-01

    Measurements of traction stresses exerted by adherent cells or cell colonies on elastic substrates have yielded new insight on how the mechanical and geometrical properties of the substrate regulate cellular force distribution, mechanical energy, spreading, morphology or stress ber architecture. We have developed a generic mechanical model of adherent cells as an active contractile gel mechanically coupled to an elastic substrate and to neighboring cells in a tissue. The contractile gel model accurately predicts the distribution of cellular and traction stresses as observed in single cell experiments, and captures the dependence of cell shape, traction stresses and stress ber polarization on the substrate's mechanical and geometrical properties. The model further predicts that the total strain energy of an adherent cell is solely regulated by its spread area, in agreement with recent experiments on micropatterned substrates with controlled geometry. When used to describe the behavior of colonies of adherent epithelial cells, the model demonstrates the crucial role of the mechanical cross-talk between intercellular and extracellular adhesion in regulating traction force distribution. Strong intercellular mechanical coupling organizes traction forces to the colony periphery, whereas weaker intercellular coupling leads to the build up of traction stresses at intercellular junctions. Furthermore, in agreement with experiments on large cohesive keratinocyte colonies, the model predicts a linear scaling of traction forces with the colony size. This scaling suggests the emergence of an effective surface tension as a scale-free material property of the adherent tissue, originating from actomyosin contractility.

  6. Improved ant colony algorithm for global path planning

    NASA Astrophysics Data System (ADS)

    Li, Pengfei; Wang, Hongbo; Li, Xiaogang

    2017-03-01

    The ant colony algorithm has many advantages compared with other algorithms in path planning, but its shortcomings still cannot be ignored. For example, the convergence speed is very low at initial stage, it is easy to fall into the local optimal solution, and the solution speed is slow and so on. In order to solve these problems and reduce the search time, this paper firstly makes the assignment of the main parameters of α, β, M and ρ in the ant colony algorithm through a large number of experimental data analysis. Then an improved ant colony algorithm based on dynamic parameters and new pheromone updating mechanism is proposed in this paper. Simulation results show that the improved ant colony algorithm can not only greatly shorten the algorithm running time, but also has greater probability to get the global optimal solution, and the convergence rate of algorithm is better than traditional ant colony algorithm. It is very advantageous for solving large-scale optimization problems.

  7. Bait distribution among multiple colonies of Pharaoh ants (hymenoptera: Formicidae).

    PubMed

    Oi, D H; Vail, K M; Williams, D F

    2000-08-01

    Pharaoh ant, Monomorium pharaonis (L.), infestations often consist of several colonies located at different nest sites. To achieve control, it is desirable to suppress or eliminate the populations of a majority of these colonies. We compared the trophallactic distribution and efficacy of two ant baits, with different modes of action, among groups of four colonies of Pharaoh ants. Baits contained either the metabolic-inhibiting active ingredient hydramethylnon or the insect growth regulator (IGR) pyriproxyfen. Within 3 wk, the hydramethylnon bait reduced worker and brood populations by at least 80%, and queen reductions ranged between 73 and 100%, when nests were in proximity (within 132 cm) to the bait source. However, these nest sites were reoccupied by ants from other colonies located further from the bait source. The pyriproxyfen bait was distributed more thoroughly to all nest locations with worker populations gradually declining by 73% at all nest sites after 8 wk. Average queen reductions ranged from 31 to 49% for all nest sites throughout the study. Even though some queens survived, brood reductions were rapid in the pyriproxyfen treatment, with reductions of 95% at all locations by week 3. Unlike the metabolic inhibitor, the IGR did not kill adult worker ants quickly, thus, more surviving worker ants were available to distribute the bait to all colonies located at different nest sites. Thus, from a single bait source, the slow-acting bait toxicant provided gradual, but long-term control, whereas the fast-acting bait toxicant provided rapid, localized control for a shorter duration.

  8. Ant colonies prefer infected over uninfected nest sites.

    PubMed

    Pontieri, Luigi; Vojvodic, Svjetlana; Graham, Riley; Pedersen, Jes Søe; Linksvayer, Timothy A

    2014-01-01

    During colony relocation, the selection of a new nest involves exploration and assessment of potential sites followed by colony movement on the basis of a collective decision making process. Hygiene and pathogen load of the potential nest sites are factors worker scouts might evaluate, given the high risk of epidemics in group-living animals. Choosing nest sites free of pathogens is hypothesized to be highly efficient in invasive ants as each of their introduced populations is often an open network of nests exchanging individuals (unicolonial) with frequent relocation into new nest sites and low genetic diversity, likely making these species particularly vulnerable to parasites and diseases. We investigated the nest site preference of the invasive pharaoh ant, Monomorium pharaonis, through binary choice tests between three nest types: nests containing dead nestmates overgrown with sporulating mycelium of the entomopathogenic fungus Metarhizium brunneum (infected nests), nests containing nestmates killed by freezing (uninfected nests), and empty nests. In contrast to the expectation pharaoh ant colonies preferentially (84%) moved into the infected nest when presented with the choice of an infected and an uninfected nest. The ants had an intermediate preference for empty nests. Pharaoh ants display an overall preference for infected nests during colony relocation. While we cannot rule out that the ants are actually manipulated by the pathogen, we propose that this preference might be an adaptive strategy by the host to "immunize" the colony against future exposure to the same pathogenic fungus.

  9. Periodic Colony Formation by Bacterial Species Bacillus subtilis

    NASA Astrophysics Data System (ADS)

    Wakita, Jun-ichi; Shimada, Hirotoshi; Itoh, Hiroto; Matsuyama, Tohey; Matsushita, Mitsugu

    2001-03-01

    We have investigated the periodic colony growth of bacterial species Bacillus subtilis. A colony grows cyclically with the interface repeating an advance (migration phase) and a rest (consolidation phase) alternately on a surface of semi-solid agar plate under appropriate environmental conditions, resulting in a concentric ring-like colony. It was found from macroscopic observations that the characteristic quantities for the periodic growth such as the migration time, the consolidation time and the terrace spacing do not depend so much on nutrient concentration Cn, but do on agar concentration Ca. The consolidation time was a weakly increasing function of Ca, while the migration time and the terrace spacing were, respectively, weakly and strongly decreasing function of Ca. Overall, the cycle (migration-plus-consolidation) time seems to be constant, and does not depend so much on both Cn and Ca. Microscopically, bacterial cells inside the growing front of a colony keep increasing their population during both migration and consolidation phases. It was also confirmed that their secreting surfactant called surfactin does not affect their periodic growth qualitatively, i.e., mutant cells which cannot secrete surfactin produce a concentric ring-like colony. All these results suggest that the diffusion of the nutrient and the surfactin are irrelevant to their periodic growth.

  10. American Colony in Africa: Lessons Learned from Other Former Colonial Powers in West Africa That Can Be Applied to the United States’ Relationship with Liberia

    DTIC Science & Technology

    2016-06-10

    possible between the US and France in Africa. Mr Knight, thank you for all of your grammar and technical corrections. This input helped improve my...colonial period. The post-colonial relationship between Guinea, Ivory Coast, and France clearly demonstrate how the relationship between a former...Great Britain and France have a long colonial history in Africa and have 5 struggled to figure out post-colonial relationships. Figuring out how to

  11. The acceptance rate of young wasps by alien colonies depends on colony developmental stages in the swarm-founding wasp, Polybia paulista von ihering (Hymenoptera: Vespidae).

    PubMed

    Kudô, Kazuyuki; Hozumi, Satoshi; Mateus, Sidnei; Zucchi, Ronaldo

    2010-01-01

    In social insects, newly emerged individuals learn the colony-specific chemical label from their natal comb shortly after their emergence. These labels help to identify each individual's colony of origin and are used as a recognition template against which individuals can discriminate nestmates from non-nestmates. Our previous studies with Polybia paulista von Ihering support this general pattern, and the acceptance rate of young female and male wasps decreased as a function of their age. Our study also showed in P. paulista that more than 90% of newly emerged female wasps might be accepted by conspecific unrelated colonies. However, it has not been investigated whether the acceptance rate of newly emerged female wasps depends on colony developmental stage of recipient colonies. We introduced newly emerged female wasps of P. paulista into different colony developmental stags of recipient colonies, i.e., worker-producing and male-producing colonies. We found that the acceptance rate of newly emerged female wasps by alien colonies was pretty lower by male-producing colonies than worker-producing colonies. This is the first study to show that the acceptance rate of young female wasps depends on stages of recipient colonies.

  12. Growth of human hemopoietic colonies in response to recombinant gibbon interleukin 3: comparison with human recombinant granulocyte and granulocyte-macrophage colony-stimulating factor

    SciTech Connect

    Messner, H.A.; Yamasaki, K.; Jamal, N.; Minden, M.M.; Yang, Y.C.; Wong, G.G.; Clark, S.C.

    1987-10-01

    Supernatants of COS-1 cells transfected with gibbon cDNA encoding interleukin 3 (IL-3) with homology to sequences for human IL-3 were tested for ability to promote growth of various human hemopoietic progenitors. The effect of these supernatants as a source of recombinant IL-3 was compared to that of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) and granulocyte colony-stimulating factor (G-CSF) as well as to that of medium conditioned by phytohemagglutinin-stimulated leukocytes. The frequency of multilineage colonies, erythroid bursts, and megakaryocyte colonies in cultures containing the COS-1 cell supernatant was equivalent to the frequency observed in the controls and significantly higher than found in cultures plated with recombinant GM-CSF. G-CSF did not support the formation of multilineage colonies, erythroid bursts, and megakaryocyte colonies. In contrast, growth of granulocyte-macrophage colonies was best supported with GM-CSF, while recombinant IL-3 yielded colonies at lower or at best equivalent frequency. The simultaneous addition of higher concentrations of GM-CSF to cultures containing IL-3 in optimal amounts did not enhance the formation of multilineage colonies, erythroid bursts, and megakaryocyte colonies. However, the frequency of such colonies and bursts increased with GM-CSF when cultures were plated with suboptimal concentrations of IL-3. Growth of colonies within the granulocyte-macrophage lineage is optimally supported by GM-CSF and does not increase with further addition of IL-3.

  13. Reconceiving Motherhood: Infanticide and Abortion in Colonial Mexico.

    PubMed

    Jaffary, Nora E

    2012-01-01

    Colonial authorities prosecuted surprisingly few women for the crimes of abortion and infanticide in viceregal Mexico. Although criminal courts tried hundreds of such cases in the nineteenth century, only a handful of trials survive from Mexico’s colonial era. This article examines criminal and inquisition records, jurisprudence, and medical texts to try to explain this discrepancy. The available evidence suggests that women in colonial Mexico did commit infanticide and abortion much more frequently than the surviving documentary record implies but that neither their peers nor courts viewed the crimes as harshly as they would in later periods. Women successfully concealed the crimes, the public declined to view these acts as criminal, and criminal courts treated them with leniency. Justices, members of the public, and mothers themselves privileged other factors, particularly fiscal concerns and the maintenance of codes of female honor, above a concern with the crimes of infanticide and abortion.

  14. Trichuris trichiura in a post-Colonial Brazilian mummy

    PubMed Central

    Bianucci, Rafaella; Torres, Eduardo J Lopes; Santiago, Juliana MF Dutra; Ferreira, Luis F; Nerlich, Andreas G; de Souza, Sheila Maria Mendonça; Giuffra, Valentina; Chieffi, Pedro Paulo; Bastos, Otilio Machado; Travassos, Renata; de Souza, Wanderley; Araújo, Adauto

    2015-01-01

    Trichuris trichiura is a soil-transmitted helminth which is prevalent in warm, moist, tropical and subtropical regions of the world with poor sanitation. Heavy whipworm can result either in Trichuris dysenteric syndrome - especially in children - or in a chronic colitis. In heavy infections, worms can spread proximally and may cause ileitis. Here we provide first microscopic evidence for a T. trichiura adult worm embedded in the rectum of a post-Colonial Brazilian adult mummy. During Colonial and post-Colonial times, many European chroniclers described a parasitic disease named Maculo whose symptomatology coincides with heavy helminthiasis. Based on our findings and on comparison of ancient textual evidence with modern description of heavy whipworm, we feel confident in considering that the two syndromes are expressions of the same pathological condition. PMID:25742276

  15. Giant vesicles "colonies": a model for primitive cell communities.

    PubMed

    Carrara, Paolo; Stano, Pasquale; Luisi, Pier Luigi

    2012-07-09

    Current research on the origin of life typically focuses on the self-organisation of molecular components in individual cell-like compartments, thereby bringing about the emergence of self-sustaining minimal cells. This is justified by the fact that single cells are the minimal forms of life. No attempts have been made to investigate the cooperative mechanisms that could derive from the assembly of individual compartments. Here we present a novel experimental approach based on vesicles "colonies" as a model of primitive cell communities. Experiments show that several advantages could have favoured primitive cell colonies when compared with isolated primitive cells. In fact there are two novel unexpected features typical of vesicle colonies, namely solute capture and vesicle fusion, which can be seen as the basic physicochemical mechanisms at the origin of life.

  16. Artificial Bee Colony Optimization for Short-Term Hydrothermal Scheduling

    NASA Astrophysics Data System (ADS)

    Basu, M.

    2014-12-01

    Artificial bee colony optimization is applied to determine the optimal hourly schedule of power generation in a hydrothermal system. Artificial bee colony optimization is a swarm-based algorithm inspired by the food foraging behavior of honey bees. The algorithm is tested on a multi-reservoir cascaded hydroelectric system having prohibited operating zones and thermal units with valve point loading. The ramp-rate limits of thermal generators are taken into consideration. The transmission losses are also accounted for through the use of loss coefficients. The algorithm is tested on two hydrothermal multi-reservoir cascaded hydroelectric test systems. The results of the proposed approach are compared with those of differential evolution, evolutionary programming and particle swarm optimization. From numerical results, it is found that the proposed artificial bee colony optimization based approach is able to provide better solution.

  17. Rebel girls? Unplanned pregnancy and colonialism in highlands Papua, Indonesia.

    PubMed

    Butt, Leslie; Munro, Jenny

    2007-01-01

    In highlands Papua, Indonesia, rapid social change under a colonial system of governance has created novel sexual opportunities for young indigenous women. Recent scholarship has viewed similar youthful sexual practices that challenge the status quo as expressions of personal agency. By looking at how young women and their families cope with unplanned pregnancies, we suggest that a more viable analytic approach would be to view sexuality, pregnancy and childbirth as a single unit of analysis. From this perspective, young women's experiences are primarily ones of constraint. Case studies offer insights into the ways a political context of colonial domination limits options and choices for young women who have children born out of wedlock. In particular, this paper describes how the 'settler gaze' - omnipresent colonial norms and judgments - creates regulatory effects in the realm of reproduction.

  18. Modeling colony collapse disorder in honeybees as a contagion.

    PubMed

    Kribs-Zaleta, Christopher M; Mitchell, Christopher

    2014-12-01

    Honeybee pollination accounts annually for over $14 billion in United States agriculture alone. Within the past decade there has been a mysterious mass die-off of honeybees, an estimated 10 million beehives and sometimes as much as 90% of an apiary. There is still no consensus on what causes this phenomenon, called Colony Collapse Disorder, or CCD. Several mathematical models have studied CCD by only focusing on infection dynamics. We created a model to account for both healthy hive dynamics and hive extinction due to CCD, modeling CCD via a transmissible infection brought to the hive by foragers. The system of three ordinary differential equations accounts for multiple hive population behaviors including Allee effects and colony collapse. Numerical analysis leads to critical hive sizes for multiple scenarios and highlights the role of accelerated forager recruitment in emptying hives during colony collapse.

  19. Effects of introducing foxes and raccoons on herring gull colonies

    USGS Publications Warehouse

    Kadlec, J.A.

    1971-01-01

    Red foxes (Vulpes fulva) and raccoons (Procyon lotor) released at colonies of herring gulls (Larus argentatus) on islands off the Massachusetts coast effectively eliminated the production of young gulls. Annual predator introductions for 2-4 years caused major reductions in colony size and occasionally total abandonment of the island as a colony site. Observations of the experimental islands for 2 years after cessation of predator introductions showed slow repopulation of the islands and lower breeding success than on control islands. The size of the regional population was reduced largely because of the movements of gulls off the experimental islands. The introduced predators are, in most cases, difficult to maintain on the islands; this restricts their utility in population management.

  20. Trichuris trichiura in a post-Colonial Brazilian mummy.

    PubMed

    Bianucci, Rafaella; Torres, Eduardo J Lopes; Santiago, Juliana M F Dutra; Ferreira, Luis F; Nerlich, Andreas G; Souza, Sheila Maria Mendonça de; Giuffra, Valentina; Chieffi, Pedro Paulo; Bastos, Otilio Maria; Travassos, Renata; Souza, Wanderley de; Araújo, Adauto

    2015-02-01

    Trichuris trichiura is a soil-transmitted helminth which is prevalent in warm, moist, tropical and subtropical regions of the world with poor sanitation. Heavy whipworm can result either in Trichuris dysenteric syndrome - especially in children - or in a chronic colitis. In heavy infections, worms can spread proximally and may cause ileitis. Here we provide first microscopic evidence for a T. trichiura adult worm embedded in the rectum of a post-Colonial Brazilian adult mummy. During Colonial and post-Colonial times, many European chroniclers described a parasitic disease named Maculo whose symptomatology coincides with heavy helminthiasis. Based on our findings and on comparison of ancient textual evidence with modern description of heavy whipworm, we feel confident in considering that the two syndromes are expressions of the same pathological condition.

  1. Amplification of Emerging Viruses in a Bat Colony

    PubMed Central

    Drexler, Jan Felix; Corman, Victor Max; Wegner, Tom; Tateno, Adriana Fumie; Zerbinati, Rodrigo Melim; Gloza-Rausch, Florian; Seebens, Antje; Müller, Marcel A.

    2011-01-01

    Bats host noteworthy viral pathogens, including coronaviruses, astroviruses, and adenoviruses. Knowledge on the ecology of reservoir-borne viruses is critical for preventive approaches against zoonotic epidemics. We studied a maternity colony of Myotis myotis bats in the attic of a private house in a suburban neighborhood in Rhineland-Palatinate, Germany, during 2008, 2009, and 2010. One coronavirus, 6 astroviruses, and 1 novel adenovirus were identified and monitored quantitatively. Strong and specific amplification of RNA viruses, but not of DNA viruses, occurred during colony formation and after parturition. The breeding success of the colony was significantly better in 2010 than in 2008, in spite of stronger amplification of coronaviruses and astroviruses in 2010, suggesting that these viruses had little pathogenic influence on bats. However, the general correlation of virus and bat population dynamics suggests that bats control infections similar to other mammals and that they may well experience epidemics of viruses under certain circumstances. PMID:21392436

  2. Alexander von Humboldt's perceptions of colonial Spanish America.

    PubMed

    Rebok, Sandra

    2009-01-01

    This study presents an in-depth analysis of Alexander von Humboldt's descriptions and critical comments on the colonial society of the different regions he visited during his well-known expedition through the Americas (1799-1804). The criticisms of colonialism that he expressed, reflecting his personal convictions, have already been the focal point of many studies, but Humboldt also was able to offer a more differentiated assessment through comparisons of regional and local traditions and developments. This essay focuses on his personal diaries, which offer many interesting comments on colonial societies. These considerations and impressions made during the expedition are of particular scholarly value since they were not subject to censorship of any kind.

  3. Budding yeast colony growth study based on circular granular cell

    NASA Astrophysics Data System (ADS)

    Aprianti, Devi; Khotimah, S. N.; Viridi, S.

    2016-08-01

    Yeast colony growth can be modelled by using circular granular cells, which can grow and produce buds. The bud growth angle can be set to regulate cell budding pattern. Cohesion force, contact force and Stokes force were adopted to accommodate the behaviour and interactions among cells. Simulation steps are divided into two steps, the explicit step is due to cell growing and implicit step for the cell rearrangement. Only in explicit step that time change was performed. In this study, we examine the influence of cell diameter growth time and reproduction time combination toward the growth of cell number and colony formation. We find a commutative relation between the cell diameter growth time and reproduction time to the specific growth rate. The greater value of the multiplication of the parameters, the smaller specific growth rate is obtained. It also shows a linear correlation between the specific growth rate and colony diameter growth rate.

  4. Morphological Changes in Growth Phenomena of Bacterial Colony Patterns

    NASA Astrophysics Data System (ADS)

    Ohgiwari, Masahiro; Matsushita, Mitsugu; Matsuyama, Tohey

    1992-03-01

    We have investigated the morphological change in colonies of bacteria called Bacillus subtilis. Patterns of colonies grown on the surface of thin agar plates were found to change drastically through the variation of environmental conditions; concentrations of nutrient Cn and agar Ca in the agar medium. They were classified into five types; DLA-like, Eden-like, DBM-like, intermediate and homogeneously spreading. The active movement of individual bacterial cells was seen in expanding periphery of a colony at intermediate and low Ca (soft agar medium). Such bacterial cell movements are found to induce the shift from DLA- and Eden-like patterns to those found for softer agar medium. Physical implication of the pattern changes is discussed.

  5. Gonococcal pilus subunit size heterogeneity correlates with transitions in colony piliation phenotype, not with changes in colony opacity

    PubMed Central

    1983-01-01

    The apparent subunit sizes for pili of gonococci (Gc) have been visualized by using either Iodogen 125I-labeled whole Gc or immunoblotting with antipilus antiserum. These methods permitted definition of pilus subunit sizes for Gc of a given strain that had undergone changes either in piliation phenotype or in colonial opacity/protein II phenotype. The results indicate that pilus subunit size does not change coincident with changes in colony opacity/protein II phenotypes; but change in pilus subunit size is seen after a change in piliation phenotype (P+ leads to P++, and vice versa). Marked diversity in pilus subunit sizes is found for Gc of individual strains when P+ derivatives of P- colonies are compared. This diversity extends to pilus subunits of Gc found in single colonies; two distinct pilus forms were demonstrated for Gc residing in several single colonies. These findings show that Gc of a given strain are able to express any of a number of different pilus subunit size forms. PMID:6138388

  6. The Regulation of Ant Colony Foraging Activity without Spatial Information

    PubMed Central

    Prabhakar, Balaji; Dektar, Katherine N.; Gordon, Deborah M.

    2012-01-01

    Many dynamical networks, such as the ones that produce the collective behavior of social insects, operate without any central control, instead arising from local interactions among individuals. A well-studied example is the formation of recruitment trails in ant colonies, but many ant species do not use pheromone trails. We present a model of the regulation of foraging by harvester ant (Pogonomyrmex barbatus) colonies. This species forages for scattered seeds that one ant can retrieve on its own, so there is no need for spatial information such as pheromone trails that lead ants to specific locations. Previous work shows that colony foraging activity, the rate at which ants go out to search individually for seeds, is regulated in response to current food availability throughout the colony's foraging area. Ants use the rate of brief antennal contacts inside the nest between foragers returning with food and outgoing foragers available to leave the nest on the next foraging trip. Here we present a feedback-based algorithm that captures the main features of data from field experiments in which the rate of returning foragers was manipulated. The algorithm draws on our finding that the distribution of intervals between successive ants returning to the nest is a Poisson process. We fitted the parameter that estimates the effect of each returning forager on the rate at which outgoing foragers leave the nest. We found that correlations between observed rates of returning foragers and simulated rates of outgoing foragers, using our model, were similar to those in the data. Our simple stochastic model shows how the regulation of ant colony foraging can operate without spatial information, describing a process at the level of individual ants that predicts the overall foraging activity of the colony. PMID:22927811

  7. The regulation of ant colony foraging activity without spatial information.

    PubMed

    Prabhakar, Balaji; Dektar, Katherine N; Gordon, Deborah M

    2012-01-01

    Many dynamical networks, such as the ones that produce the collective behavior of social insects, operate without any central control, instead arising from local interactions among individuals. A well-studied example is the formation of recruitment trails in ant colonies, but many ant species do not use pheromone trails. We present a model of the regulation of foraging by harvester ant (Pogonomyrmex barbatus) colonies. This species forages for scattered seeds that one ant can retrieve on its own, so there is no need for spatial information such as pheromone trails that lead ants to specific locations. Previous work shows that colony foraging activity, the rate at which ants go out to search individually for seeds, is regulated in response to current food availability throughout the colony's foraging area. Ants use the rate of brief antennal contacts inside the nest between foragers returning with food and outgoing foragers available to leave the nest on the next foraging trip. Here we present a feedback-based algorithm that captures the main features of data from field experiments in which the rate of returning foragers was manipulated. The algorithm draws on our finding that the distribution of intervals between successive ants returning to the nest is a Poisson process. We fitted the parameter that estimates the effect of each returning forager on the rate at which outgoing foragers leave the nest. We found that correlations between observed rates of returning foragers and simulated rates of outgoing foragers, using our model, were similar to those in the data. Our simple stochastic model shows how the regulation of ant colony foraging can operate without spatial information, describing a process at the level of individual ants that predicts the overall foraging activity of the colony.

  8. Colony differences in response to trapping in roseate terns

    USGS Publications Warehouse

    Burger, J.; Nisbet, I.C.T.; Zingo, J.M.; Spendelow, J.A.; Safina, C.; Gochfeld, M.

    1995-01-01

    Both members of seabird pairs are normally required to fledge young. Seabirds that nest in sites accessible to predators usually have one parent in attendance during the egg/chick phase. Time devoted to foraging can vary with individual skill and age, prey availability and abundance (Seamy 1978), and distance to foraging grounds (Safina 1990). Although average skill of similar-aged individuals should not vary from colony to colony (Ryder 1980), prey availability and abundance, and spatial distribution of foraging grounds may vary. Thus, the percent of time both members of a pair are present at the nest site may vary in different colonies. In this paper, we examine parental behavior in response to trapping in Roseate Terns (Sterna dougallii) nesting in three of the six major colonies in the northeastern United States: Cedar Beach, New York, Falkner Island, Connecticut; and Bird Island, Massachusetts. Roseate Terns were listed on the United States? Endangered Species List in 1987. We were interested in differences among colonies in how often both parents were present, how soon a mate returned to the nest if one parent was temporarily removed, how soon a trapped bird returned to the nest after release, and the time during which the nest was left unguarded. We feel it is important to recognize and make management decisions based on colony differences where they exist. Our study follows directly from earlier work at Cedar Beach on trapping vulnerability of Common Terns (Sterna hirundo) and Roseate Terns. Nisbet reported that Roseate Terns at Bird Island required about three hours to return to the nest after trapping.

  9. Leprosy: disease, isolation, and segregation in colonial Mozambique.

    PubMed

    Zamparoni, Valdemir

    2016-11-16

    Drawing on documents produced between the early nineteenth and mid-twentieth centuries, mainly medical reports, this paper indicates the prevailing conceptions in the colonial medical community and local populations about leprosy, its manifestations, and how to deal with it. It focuses on the tensions concerning the practice of segregating lepers and its social and sanitation implications. To comprehend the roots of the discourses and strategies in the Portuguese and colonial medical environment, the trajectory of the definitions of isolation, segregation, and leprosy are traced, as are their use in or absence from the writings of missionaries, chroniclers, and doctors in Angola and Mozambique as of the second half of the seventeenth century.

  10. Dyes as fungal inhibitors: effect on colony diameter.

    PubMed Central

    Bragulat, M R; Abarca, M L; Bruguera, M T; Cabañes, F J

    1991-01-01

    The effects of a wide range of concentrations of 13 dyes on the colony diameters of nine fungal strains (including members of the Deuteromycetes and Zygomycetes) were evaluated. Auramine at a concentration of 50 ppm (50 micrograms/ml), methylene blue at a concentration of 500 ppm, gentian violet at a concentration of 5 ppm, and phenol red at a concentration of 50 ppm performed as well as the commonly used dyes dichloran at a concentration of 2 ppm and rose bengal at a concentration of 50 ppm in that they allowed adequate colony development of the Deuteromycetes strains tested and controlled rapidly spreading fungi. PMID:1768153

  11. Indigenous knowledge in the science curriculum: avoiding neo-colonialism

    NASA Astrophysics Data System (ADS)

    Ryan, Ann

    2008-09-01

    Science education in Papua New Guinea has been influenced by neo-colonial practices that have significantly contributed to the silencing of the Papua New Guinea voice. This silencing has led to the production of science curriculum documents that are irrelevant to the students for whom they are written. To avoid being caught up in neo-colonial practices, Western science educators ought to consider the notion of cultural mediators. This position, I argue, infers an obligation to take responsibility for their actions and to consider postcolonial discourses as a way of understanding the relationships and dialogue between different ways of knowing.

  12. Management of precancerous conditions and lesions in the stomach (MAPS): guideline from the European Society of Gastrointestinal Endoscopy (ESGE), European Helicobacter Study Group (EHSG), European Society of Pathology (ESP), and the Sociedade Portuguesa de Endoscopia Digestiva (SPED).

    PubMed

    Dinis-Ribeiro, M; Areia, M; de Vries, A C; Marcos-Pinto, R; Monteiro-Soares, M; O'Connor, A; Pereira, C; Pimentel-Nunes, P; Correia, R; Ensari, A; Dumonceau, J M; Machado, J C; Macedo, G; Malfertheiner, P; Matysiak-Budnik, T; Megraud, F; Miki, K; O'Morain, C; Peek, R M; Ponchon, T; Ristimaki, A; Rembacken, B; Carneiro, F; Kuipers, E J

    2012-01-01

    Atrophic gastritis, intestinal metaplasia, and epithelial dysplasia of the stomach are common and are associated with an increased risk for gastric cancer. In the absence of guidelines, there is wide disparity in the management of patients with these premalignant conditions. The European Society of Gastrointestinal Endoscopy (ESGE), the European Helicobacter Study Group (EHSG), the European Society of Pathology (ESP) and the Sociedade Portuguesa de Endoscopia Digestiva (SPED) have therefore combined efforts to develop evidence-based guidelines on the management of patients with precancerous conditions and lesions of the stomach (termed MAPS). A multidisciplinary group of 63 experts from 24 countries developed these recommendations by means of repeat online voting and a meeting in June 2011 in Porto, Portugal. The recommendations emphasize the increased cancer risk in patients with gastric atrophy and metaplasia, and the need for adequate staging in the case of high grade dysplasia, and they focus on treatment and surveillance indications and methods.

  13. Management of precancerous conditions and lesions in the stomach (MAPS): guideline from the European Society of Gastrointestinal Endoscopy (ESGE), European Helicobacter Study Group (EHSG), European Society of Pathology (ESP), and the Sociedade Portuguesa de Endoscopia Digestiva (SPED).

    PubMed

    Dinis-Ribeiro, M; Areia, M; de Vries, A C; Marcos-Pinto, R; Monteiro-Soares, M; O'Connor, A; Pereira, C; Pimentel-Nunes, P; Correia, R; Ensari, A; Dumonceau, J M; Machado, J C; Macedo, G; Malfertheiner, P; Matysiak-Budnik, T; Megraud, F; Miki, K; O'Morain, C; Peek, R M; Ponchon, T; Ristimaki, A; Rembacken, B; Carneiro, F; Kuipers, E J

    2012-01-01

    Atrophic gastritis, intestinal metaplasia, and epithelial dysplasia of the stomach are common and are associated with an increased risk for gastric cancer. In the absence of guidelines, there is wide disparity in the management of patients with these premalignant conditions. The European Society of Gastrointestinal Endoscopy, the European Helicobacter Study Group, the European Society of Pathology, and the Sociedade Portuguesa de Endoscopia Digestiva have therefore combined efforts to develop evidence-based guidelines on the management of patients with precancerous conditions and lesions of the stomach. A multidisciplinary group of 63 experts from 24 countries developed these recommendations by means of repeat online voting and a meeting in June 2011 in Porto, Portugal. The recommendations emphasize the increased cancer risk in patients with gastric atrophy and metaplasia and the need for adequate staging in the case of high-grade dysplasia, and they focus on treatment and surveillance indications and methods.

  14. Management of precancerous conditions and lesions in the stomach (MAPS): guideline from the European Society of Gastrointestinal Endoscopy (ESGE), European Helicobacter Study Group (EHSG), European Society of Pathology (ESP), and the Sociedade Portuguesa de Endoscopia Digestiva (SPED)

    PubMed Central

    Dinis-Ribeiro, M.; Areia, M.; de Vries, A. C.; Marcos-Pinto, R.; Monteiro-Soares, M.; O'Connor, A.; Pereira, C.; Pimentel-Nunes, P.; Correia, R.; Ensari, A.; Dumonceau, J. M.; Machado, J. C.; Macedo, G.; Malfertheiner, P.; Matysiak-Budnik, T.; Megraud, F.; Miki, K.; O'Morain, C.; Peek, R. M.; Ponchon, T.; Ristimaki, A.; Rembacken, B.; Carneiro, F.; Kuipers, E. J.

    2012-01-01

    Atrophic gastritis, intestinal metaplasia, and epithelial dysplasia of the stomach are common and are associated with an increased risk for gastric cancer. In the absence of guidelines, there is wide disparity in the management of patients with these premalignant conditions. The European Society of Gastrointestinal Endoscopy (ESGE), the European Helicobacter Study Group (EHSG), the European Society of Pathology (ESP) and the Sociedade Portuguesa de Endoscopia Digestiva (SPED) have therefore combined efforts to develop evidence-based guidelines on the management of patients with precancerous conditions and lesions of the stomach (termed MAPS). A multidisciplinary group of 63 experts from 24 countries developed these recommendations by means of repeat online voting and a meeting in June 2011 in Porto, Portugal. The recommendations emphasize the increased cancer risk in patients with gastric atrophy and metaplasia, and the need for adequate staging in the case of high grade dysplasia, and they focus on treatment and surveillance indications and methods. PMID:22198778

  15. Bumble bee colony dynamics: quantifying the importance of land use and floral resources for colony growth and queen production.

    PubMed

    Crone, Elizabeth E; Williams, Neal M

    2016-04-01

    Bumble bee (Bombus) species are ecologically and economically important pollinators, and many species are in decline. In this article, we develop a mechanistic model to analyse growth trajectories of Bombus vosnesenskii colonies in relation to floral resources and land use. Queen production increased with floral resources and was higher in semi-natural areas than on conventional farms. However, the most important parameter for queen production was the colony growth rate per flower, as opposed to the average number of available flowers. This result indicates the importance of understanding mechanisms of colony growth, in order to predict queen production and enhance bumble bee population viability. Our work highlights the importance of interpreting bumble bee conservation efforts in the context of overall population dynamics and provides a framework for doing so. © 2016 John Wiley & Sons Ltd/CNRS.

  16. Division of labour in colony defence against vertebrate predators by the social wasp Polistes fuscatus.

    PubMed

    Judd

    2000-07-01

    In this study I examined how the paper wasp, Polistes fuscatus, defends a colony when faced with a vertebrate attack. I looked for a division of labour in defensive behaviour within a colony and examined whether this behaviour changes over the colony cycle. The colonies were presented with a model of an adult red-winged blackbird, Agelaius phoeniceus, and a speaker that vibrated the comb. There was a pronounced division of labour in the defence against vertebrate predators within a colony. The queen was consistently the most aggressive individual in the colony. The subordinate foundresses and workers both became more aggressive towards a vertebrate predator as they aged. Gynes and males did not participate in colony defence. The level of aggression in colony members of P. fuscatus appears to be related to the reproductive investment of the colony. Copyright 2000 The Association for the Study of Animal Behaviour.

  17. Edges of human embryonic stem cell colonies display distinct mechanical properties and differentiation potential

    PubMed Central

    Rosowski, Kathryn A.; Mertz, Aaron F.; Norcross, Samuel; Dufresne, Eric R.; Horsley, Valerie

    2015-01-01

    In order to understand the mechanisms that guide cell fate decisions during early human development, we closely examined the differentiation process in adherent colonies of human embryonic stem cells (hESCs). Live imaging of the differentiation process reveals that cells on the outer edge of the undifferentiated colony begin to differentiate first and remain on the perimeter of the colony to eventually form a band of differentiation. Strikingly, this band is of constant width in all colonies, independent of their size. Cells at the edge of undifferentiated colonies show distinct actin organization, greater myosin activity and stronger traction forces compared to cells in the interior of the colony. Increasing the number of cells at the edge of colonies by plating small colonies can increase differentiation efficiency. Our results suggest that human developmental decisions are influenced by cellular environments and can be dictated by colony geometry of hESCs. PMID:26391588

  18. BEEHAVE: a systems model of honeybee colony dynamics and foraging to explore multifactorial causes of colony failure.

    PubMed

    Becher, Matthias A; Grimm, Volker; Thorbek, Pernille; Horn, Juliane; Kennedy, Peter J; Osborne, Juliet L

    2014-04-01

    A notable increase in failure of managed European honeybee Apis mellifera L. colonies has been reported in various regions in recent years. Although the underlying causes remain unclear, it is likely that a combination of stressors act together, particularly varroa mites and other pathogens, forage availability and potentially pesticides. It is experimentally challenging to address causality at the colony scale when multiple factors interact. In silico experiments offer a fast and cost-effective way to begin to address these challenges and inform experiments. However, none of the published bee models combine colony dynamics with foraging patterns and varroa dynamics.We have developed a honeybee model, BEEHAVE, which integrates colony dynamics, population dynamics of the varroa mite, epidemiology of varroa-transmitted viruses and allows foragers in an agent-based foraging model to collect food from a representation of a spatially explicit landscape.We describe the model, which is freely available online (www.beehave-model.net). Extensive sensitivity analyses and tests illustrate the model's robustness and realism. Simulation experiments with various combinations of stressors demonstrate, in simplified landscape settings, the model's potential: predicting colony dynamics and potential losses with and without varroa mites under different foraging conditions and under pesticide application. We also show how mitigation measures can be tested.Synthesis and applications. BEEHAVE offers a valuable tool for researchers to design and focus field experiments, for regulators to explore the relative importance of stressors to devise management and policy advice and for beekeepers to understand and predict varroa dynamics and effects of management interventions. We expect that scientists and stakeholders will find a variety of applications for BEEHAVE, stimulating further model development and the possible inclusion of other stressors of potential importance to honeybee colony

  19. BEEHAVE: a systems model of honeybee colony dynamics and foraging to explore multifactorial causes of colony failure

    PubMed Central

    Becher, Matthias A; Grimm, Volker; Thorbek, Pernille; Horn, Juliane; Kennedy, Peter J; Osborne, Juliet L

    2014-01-01

    A notable increase in failure of managed European honeybee Apis mellifera L. colonies has been reported in various regions in recent years. Although the underlying causes remain unclear, it is likely that a combination of stressors act together, particularly varroa mites and other pathogens, forage availability and potentially pesticides. It is experimentally challenging to address causality at the colony scale when multiple factors interact. In silico experiments offer a fast and cost-effective way to begin to address these challenges and inform experiments. However, none of the published bee models combine colony dynamics with foraging patterns and varroa dynamics. We have developed a honeybee model, BEEHAVE, which integrates colony dynamics, population dynamics of the varroa mite, epidemiology of varroa-transmitted viruses and allows foragers in an agent-based foraging model to collect food from a representation of a spatially explicit landscape. We describe the model, which is freely available online (www.beehave-model.net). Extensive sensitivity analyses and tests illustrate the model's robustness and realism. Simulation experiments with various combinations of stressors demonstrate, in simplified landscape settings, the model's potential: predicting colony dynamics and potential losses with and without varroa mites under different foraging conditions and under pesticide application. We also show how mitigation measures can be tested. Synthesis and applications. BEEHAVE offers a valuable tool for researchers to design and focus field experiments, for regulators to explore the relative importance of stressors to devise management and policy advice and for beekeepers to understand and predict varroa dynamics and effects of management interventions. We expect that scientists and stakeholders will find a variety of applications for BEEHAVE, stimulating further model development and the possible inclusion of other stressors of potential importance to honeybee

  20. Number of colony-forming unit-Hill colonies among children and teenagers with obesity, dyslipidemia and breastfeeding history.

    PubMed

    Salazar-Martinez, E; Rodriguez-Valentin, R; Albavera-Hernandez, C; Carreon-Rodriguez, A; Lazcano-Ponce, E

    2016-06-01

    The number of colony-forming unit (CFU)-Hill colonies has been proposed as a biomarker of vascular function and cardiovascular risk in adults but information about its role in children is scarce. This study evaluates the associations between obesity, cardiovascular risk factors and breastfeeding history with the numbers of CFU-Hill colonies in a sample of young people. We selected 49 children and teenagers between ages 10 and 17 (65.3% boys) from Mexican Health Care system. Physical activity and Anthropometric measures data were registered. CFU-Hill colonies were cultured from mononuclear cells obtained from venous blood. We detected inverse associations between the formation of CFU-Hill colonies and body mass index (BMI; β = -1.53; 95% confidence interval [CI], -1.92, -1.13), triglycerides (β = -0.26; 95%CI = -0.34, -0.18), total cholesterol (β = -0.13; 95%CI = -0.17, -0.08), Low Density Lipoprotein (LDL) (β = -0.20; 95%CI = -0.31, -0.09) and glucose (β = -0.37; 95%CI = -0.55, -0.18) using multivariate models. Breastfeeding duration showed a 1.46-colony increase for each month of breastfeeding (95%CI = 0.73, 2.18). CFU-Hill colony-forming capacity in children and teenagers was inversely associated with obesity, dyslipidemia and high blood levels of glucose. In contrast a longer breastfeeding duration was directly associated with an increased number of CFU-Hill colonies. However these results must be confirmed with further studies. Our findings support the importance of promoting breastfeeding and monitoring nutritional and metabolic status at an early age to prevent chronic disease development. Copyright © 2016 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.

  1. Indigenous Knowledge in the Science Curriculum: Avoiding Neo-Colonialism

    ERIC Educational Resources Information Center

    Ryan, Ann

    2008-01-01

    Science education in Papua New Guinea has been influenced by neo-colonial practices that have significantly contributed to the silencing of the Papua New Guinea voice. This silencing has led to the production of science curriculum documents that are irrelevant to the students for whom they are written. To avoid being caught up in neo-colonial…

  2. Honeybee Colony Vibrational Measurements to Highlight the Brood Cycle

    PubMed Central

    Bencsik, Martin; Le Conte, Yves; Reyes, Maritza; Pioz, Maryline; Whittaker, David; Crauser, Didier; Simon Delso, Noa; Newton, Michael I.

    2015-01-01

    Insect pollination is of great importance to crop production worldwide and honey bees are amongst its chief facilitators. Because of the decline of managed colonies, the use of sensor technology is growing in popularity and it is of interest to develop new methods which can more accurately and less invasively assess honey bee colony status. Our approach is to use accelerometers to measure vibrations in order to provide information on colony activity and development. The accelerometers provide amplitude and frequency information which is recorded every three minutes and analysed for night time only. Vibrational data were validated by comparison to visual inspection data, particularly the brood development. We show a strong correlation between vibrational amplitude data and the brood cycle in the vicinity of the sensor. We have further explored the minimum data that is required, when frequency information is also included, to accurately predict the current point in the brood cycle. Such a technique should enable beekeepers to reduce the frequency with which visual inspections are required, reducing the stress this places on the colony and saving the beekeeper time. PMID:26580393

  3. Reliving Colonial Days in Your Classroom. Curriculum Boosters. Social Studies.

    ERIC Educational Resources Information Center

    Hennessey, Gail Skroback

    1994-01-01

    The article presents hands-on classroom projects to teach elementary students about colonial American history. Students make their own natural dyes, cook blueberry slump, and play cup-and-ball the way the colonists did. The activities integrate science, math, history, art, and language arts. (SM)

  4. Colonial Broadsides: A Student-Created Play. [Lesson Plan].

    ERIC Educational Resources Information Center

    2002

    "Broadsides" are notices written on disposable, single sheets of paper printed on one side only, intended to have an immediate impact on readers. Broadsides had an impact in colonial America--they delivered the latest news and much more: government proclamations, public service announcements, opinion papers, advertisements, and…

  5. Reliving Colonial Days in Your Classroom. Curriculum Boosters. Social Studies.

    ERIC Educational Resources Information Center

    Hennessey, Gail Skroback

    1994-01-01

    The article presents hands-on classroom projects to teach elementary students about colonial American history. Students make their own natural dyes, cook blueberry slump, and play cup-and-ball the way the colonists did. The activities integrate science, math, history, art, and language arts. (SM)

  6. Ectoparasitism shortens the breeding season in a colonial bird

    PubMed Central

    Brown, Charles R.; Brown, Mary Bomberger

    2015-01-01

    When blood-feeding parasites increase seasonally, their deleterious effects may prevent some host species, especially those living in large groups where parasites are numerous, from reproducing later in the summer. Yet the role of parasites in regulating the length of a host's breeding season—and thus the host's opportunity for multiple brooding—has not been systematically investigated. The highly colonial cliff swallow (Petrochelidon pyrrhonota), a temperate-latitude migratory songbird in the western Great Plains, USA, typically has a relatively short (eight to nine week) breeding season, with birds rarely nesting late in the summer. Colonies at which ectoparasitic swallow bugs (Oeciacus vicarius) were experimentally removed by fumigation were over 45 times more likely to have birds undertake a second round of nesting than were colonies exposed to parasites. Late nesting approximately doubled the length of the breeding season, with some birds raising two broods. Over a 27 year period the percentage of birds engaging in late nesting each year increased at a colony site where parasites were removed annually. This trend could not be explained by changes in group size, climate or nesting phenology during the study. The results suggest that ectoparasitism shortens the cliff swallow's breeding season and probably prevents many individuals from multiple brooding. When this constraint is removed, selection may rapidly favour late nesting. PMID:26064606

  7. Reflected scatterometry for noninvasive interrogation of bacterial colonies

    NASA Astrophysics Data System (ADS)

    Kim, Huisung; Doh, Iyll-Joon; Sturgis, Jennifer; Bhunia, Arun K.; Robinson, J. Paul; Bae, Euiwon

    2016-10-01

    A phenotyping of bacterial colonies on agar plates using forward-scattering diffraction-pattern analysis provided promising classification of several different bacteria such as Salmonella, Vibrio, Listeria, and E. coli. Since the technique is based on forward-scattering phenomena, light transmittance of both the colony and the medium is critical to ensure quality data. However, numerous microorganisms and their growth media allow only limited light penetration and render the forward-scattering measurement a challenging task. For example, yeast, Lactobacillus, mold, and several soil bacteria form colorful and dense colonies that obstruct most of the incoming light passing through them. Moreover, blood agar, which is widely utilized in the clinical field, completely blocks the incident coherent light source used in forward scatterometry. We present a newly designed reflection scatterometer and validation of the resolving power of the instrument. The reflectance-type instrument can acquire backward elastic scatter patterns for both highly opaque media and colonies and has been tested with three different bacterial genera grown on blood agar plates. Cross-validation results show a classification rate above 90% for four genera.

  8. Genetic Stock Identification Of Production Colonies Of Russian Honey Bees

    USDA-ARS?s Scientific Manuscript database

    The prevalence of Nosema ceranae in managed honey bee colonies has increased dramatically in the past 10 – 20 years worldwide. A variety of genetic testing methods for species identification and prevalence are now available. However sample size and preservation method of samples prior to testing hav...

  9. Recent Literature on Slavery in Colonial North America.

    ERIC Educational Resources Information Center

    Wright, Donald R.

    2003-01-01

    Provides a review of literature published on slavery in colonial North America, focusing on how this literature has changed over the years. Includes literature in topical areas, such as the Atlantic slave trade, African American culture, and race. Includes a bibliography. (CMK)

  10. Microsatellite loci for the invasive colonial hydrozoan Cordylophora caspia

    EPA Science Inventory

    Cordylophora caspia, a colonial hydrozoan native to the Ponto-Caspian region, has become a common invader of both fresh and brackish water ecosystems of North America and Europe. Here we describe 11 polymorphic microsatellite loci for this species. Preliminary analyses indicate ...

  11. The Transatlantic Slave Trade and Colonial Chesapeake Slavery.

    ERIC Educational Resources Information Center

    Walsh, Lorena S.

    2003-01-01

    Explores the slave trade system that brought slaves to the Chesapeake Bay area during the eighteenth century colonial United States. Uses information from the "Trans-Atlantic Slave Trade: A Database on CD-ROM" to examine slave routes. Provides information on the origins and distribution of slaves in the Chesapeake Bay region and the…

  12. Inglaterra, primitiva colonia espanola (England, Primitive Spanish Colony)

    ERIC Educational Resources Information Center

    Til, Brianes

    1975-01-01

    The author fantasizes that at some point in the distant past England was a Spanish colony. He supports his thesis by revealing fantastic etymologies of some English place names showing the influence of Spanish on English, for example "Surrey" comes from "su rey." (Text is in Spanish.) (TL)

  13. Methods and reagents. Reducing background colonies with positive selection vectors.

    PubMed

    Hengen, P N

    1997-03-01

    Methods and reagents is a unique monthly column that highlights current discussions in the newsgroup bionet.molbio.methds-reagnts, available on the Internet. This month's column discusses the pros and cons of eliminating unwanted background colonies by using the positive selection vector pZErO. For details on how to partake in the newsgroup, see the accompanying box.

  14. The distinction between witchcraft and madness in colonial Connecticut.

    PubMed

    Goodheart, Lawrence B

    2002-12-01

    This essay argues two points in regard to early New England: first, that witchcraft is not a significant aspect of the history of mental illness; and second, that seventeenth-century society had a cultural protocol for distinguishing one from the other. The examples discussed in detail are from Connecticut, but they are representative of colonial New England as a whole.

  15. Critical "Kapwa": Possibilities of Collective Healing from Colonial Trauma

    ERIC Educational Resources Information Center

    Desai, Maharaj

    2016-01-01

    This paper is based on the experiences of the author as a student, educator, and Filipina/o. The author explores the multiple traumas in the community that he grew up in that impacted his experiences as well as those of his family and the connection of those traumas to colonialism. The author also examines the possibilities for healing from those…

  16. Indigenous Knowledge in the Science Curriculum: Avoiding Neo-Colonialism

    ERIC Educational Resources Information Center

    Ryan, Ann

    2008-01-01

    Science education in Papua New Guinea has been influenced by neo-colonial practices that have significantly contributed to the silencing of the Papua New Guinea voice. This silencing has led to the production of science curriculum documents that are irrelevant to the students for whom they are written. To avoid being caught up in neo-colonial…

  17. Inglaterra, primitiva colonia espanola (England, Primitive Spanish Colony)

    ERIC Educational Resources Information Center

    Til, Brianes

    1975-01-01

    The author fantasizes that at some point in the distant past England was a Spanish colony. He supports his thesis by revealing fantastic etymologies of some English place names showing the influence of Spanish on English, for example "Surrey" comes from "su rey." (Text is in Spanish.) (TL)

  18. A Study of Colonial Surrogates and Indigenous Others.

    ERIC Educational Resources Information Center

    Willard, William

    1993-01-01

    Carlos Montezuma, an Apache, was raised by whites, graduated from medical school, and worked as physician for the Indian Service and Carlisle Indian School. Montezuma's life as colonial surrogate advocating "civilization" of the Indians is compared to Kafka's story of the ape who studied to become a passable European because it was "a way out" of…

  19. Surrendering a Colonial Domain: Educating North India, 1854-1890

    ERIC Educational Resources Information Center

    Allender, Tim

    2007-01-01

    Postcolonial research has often assumed that colonial education fell victim to the forces of nationalism, like other areas of Raj governance in the early twentieth century. However, European-led education that aspired to reach the general population had already failed a generation earlier, at least in north India. This was after highly imaginative…

  20. Control of Hydroid Colony Form by Surface Heterogeneity

    PubMed Central

    Buss, Leo W.; Buss, Evan D.; Anderson, Christopher P.; Power, Michael; Zinter, Joseph

    2016-01-01

    The colonial hydroid Podocoryna carnea grows adherent to surfaces progressing along them by a motile stolon tip. We here ask whether the stolon tip grows preferentially within grooves etched in silicon wafers. In a series of pilot experiments, we varied the dimensions of grooves and found that stolons did not utilize grooves with a width:depth of 5:5 μm or 10:10 μm, occasionally followed grooves 25:25 μm in size, and preferentially grew within grooves of a width:depth of 50:50 μm and 100:50 μm. We then grew colonies in grids, with fixed 50:50 μm width:depth channels intersecting at 90° every 950, 700, 450, or 150 μm. We find that stolons grew within grooves early in colony ontogeny, but remained restricted to them only in the grid pattern with channel intersections every 150 μm. Finally, we created a grid in the shape of the Yale Y logo, with channels of 50:50 μm width:depth and intersections every 100 μm. The resulting colonies conformed to that of the logo. Our findings demonstrate that stolons respond to surface heterogeneity and that surface etching can be used to fabricate microfluidic circuits comprised of hydroid perisarc. PMID:27257948

  1. The Heritage of Mexico. Volume 2: The Colonial Period.

    ERIC Educational Resources Information Center

    Burton, Paul C.

    The colonial period in Mexican history, from 1519 to the Revolution of 1910, is the subject of the second in a series of three bilingual (Spanish-English) books designed to aid teachers in presenting the historical and cultural background of the Mexican people. The series, which lends itself to the Inquiry Method of teaching, includes illustrated…

  2. Urban Economics, Conduit-Colonialism and Public Policy

    ERIC Educational Resources Information Center

    Hamilton, Charles V.

    1972-01-01

    Considerable amounts of money already come into the cities and the black communities, but go right out as payments to absentee landlords, exploitative merchants, credit gougers, and loan sharks, as well as in support of the colonial management system. (Author/JM)

  3. [Landscape influence on the Grey Herons colonies distribution].

    PubMed

    Boisteau, Benjamin; Marion, Loïc

    2006-03-01

    We analysed the spatial relationship between the location and the size of the 112 grey heron colonies existing in 1994 in the two refuge areas after their decline of the species in the 19th century in France: South Brittany (Loire-Atlantique and Morbihan), and eastern France (Haute-Saône, Saône-et-Loire, Meurthe-et-Moselle, Vosges). We tested 35 variables describing the hydrographical network surrounding the colonies from a local to a regional scale using a Geographic Information System. The results show that, whatever the scale, the distribution of the breeding colonies was not governed by the same elements of the hydrographical network in the different areas. Two strategies of spatial utilization were observed between the western and the eastern parts of France. Moreover, two quite distinct situations were also distinguished between Morbihan and Loire-Atlantique. This study stresses that the type and the spatial organization of the hydrographical elements, but also of the history of the populations, are important in the distribution of the Grey Heron colonies.

  4. Across the Colonial Divide: Conversations about Evaluation in Indigenous Contexts

    ERIC Educational Resources Information Center

    Cavino, Hayley Marama

    2013-01-01

    This essay engages questions of evaluator role and indigenous peoples participation in evaluation within colonial and decolonization contexts. Specifically, I critique the Western emphasis on cultural competence and contrast the utility of "mainstream" evaluation approaches alongside three indigenous inquiry models (Te Kotahitanga,…

  5. Host specificity and colony impacts of Solenopsis invicta virus 3

    USDA-ARS?s Scientific Manuscript database

    A thorough understanding of host specificity is essential before pathogens can be used as biopesticides or self-sustaining biocontrol agents. In order to define the host range of the recently discovered Solenopsis invicta virus 3 (SINV-3), we exposed colonies of 19 species of ants in 14 different g...

  6. Mass Spectral Molecular Networking of Living Microbial Colonies

    SciTech Connect

    Watrous, Jeramie D.; Roach, Patrick J.; Alexandrov, Theodore; Heath, Brandi S.; Yang, Jane Y.; Kersten, Roland; vander Voort, Menno; Pogliano, Kit; Gross, Harald; Raaijmakers, Jos M.; Moore, Bradley S.; Laskin, Julia; Bandeira, Nuno; Dorrestein, Pieter C.

    2012-06-26

    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 costeffective approach that allows metabolic profiling of live microbial colonies directly from a Petri dish without any sample preparation. Nanospray desorption electrospray ionization mass spectrometry (MS), combined with alignment of MS data and molecular networking, enabled monitoring of metabolite production from live microbial colonies from diverse bacterial genera, including Bacillus subtilis, Streptomyces coelicolor, Mycobacterium smegmatis, and Pseudomonas aeruginosa. This work demonstrates that, by using these tools to visualize small molecular changes within bacterial interactions, insights can be gained into bacterial developmental processes as a result of the improved organization of MS/MS data. To validate this experimental platform, metabolic profiling was performed on Pseudomonas sp. SH-C52, which protects sugar beet plants from infections by specific soil-borne fungi [R. Mendes et al. (2011) Science 332:1097–1100]. The antifungal effect of strain SHC52 was attributed to thanamycin, a predicted lipopeptide encoded by a nonribosomal peptide synthetase gene cluster. Our technology, in combination with our recently developed peptidogenomics strategy, enabled the detection and partial characterization of thanamycin and showed that it is amonochlorinated lipopeptide that belongs to the syringomycin family of antifungal agents. In conclusion, the platform presented here provides a significant advancement in our ability to understand the spatiotemporal dynamics of metabolite production in live microbial colonies and communities.

  7. Microsatellite loci for the invasive colonial hydrozoan Cordylophora caspia

    EPA Science Inventory

    Cordylophora caspia, a colonial hydrozoan native to the Ponto-Caspian region, has become a common invader of both fresh and brackish water ecosystems of North America and Europe. Here we describe 11 polymorphic microsatellite loci for this species. Preliminary analyses indicate ...

  8. Existential Thoughts in Fanon's Post-Colonialism Discourse

    ERIC Educational Resources Information Center

    Yeh, Chuan-Rong

    2013-01-01

    Frantz Fanon, a pioneer of post-colonial theory, attempted to seek some unbeknown possibilities through a Sartrean existentialism thought toward ethnic liberation and the fighting against imperialism. This article tries to enter Fanon's short life that was full of humanism and existentialist thought and to explore the hidden theoretical context…

  9. Making Colonial Subjects: Education in the Age of Empire

    ERIC Educational Resources Information Center

    Hall, Catherine

    2008-01-01

    This article explores two attempts to envisage a new global world, one created by the West, and to create new colonial subjects. One of these attempts was in Sierra Leone in the 1790s, the other in India in the 1830s. The two case studies are seen through the lens of a father and son, Zachary and Thomas Babington Macaulay, each a representative…

  10. Existential Thoughts in Fanon's Post-Colonialism Discourse

    ERIC Educational Resources Information Center

    Yeh, Chuan-Rong

    2013-01-01

    Frantz Fanon, a pioneer of post-colonial theory, attempted to seek some unbeknown possibilities through a Sartrean existentialism thought toward ethnic liberation and the fighting against imperialism. This article tries to enter Fanon's short life that was full of humanism and existentialist thought and to explore the hidden theoretical context…

  11. Missionary Education in Colonial Africa: The Critique of Mary Kingsley.

    ERIC Educational Resources Information Center

    Pearce, Robert

    1988-01-01

    Discussing missionary education in colonial Africa, Pearce examines the ideas of Mary Kingsley, one of the major influences on British thinking towards Africa from the late 1890's. Focusing attention on her educational views, Pearce states that she had influence on all areas of British policy in Africa, and especially West Africa. (GEA)

  12. Improved Modeling of Intelligent Tutoring Systems Using Ant Colony Optimization

    ERIC Educational Resources Information Center

    Rastegarmoghadam, Mahin; Ziarati, Koorush

    2017-01-01

    Swarm intelligence approaches, such as ant colony optimization (ACO), are used in adaptive e-learning systems and provide an effective method for finding optimal learning paths based on self-organization. The aim of this paper is to develop an improved modeling of adaptive tutoring systems using ACO. In this model, the learning object is…

  13. Granulocyte macrophage colony stimulating factor therapy for pulmonary alveolar proteinosis.

    PubMed

    Shende, Ruchira P; Sampat, Bhavin K; Prabhudesai, Pralhad; Kulkarni, Satish

    2013-03-01

    We report a case of 58 year old female diagnosed with Pulmonary Alveolar Proteinosis (PAP) with recurrence of PAP after 5 repeated whole lung lavage, responding to subcutaneous injections of Granulocyte Macrophage Colony Stimulating Factor therapy (GM-CSF). Thus indicating that GM-CSF therapy is a promising alternative in those requiring repeated whole lung lavage

  14. The Heritage of Mexico. Volume 2: The Colonial Period.

    ERIC Educational Resources Information Center

    Burton, Paul C.

    The colonial period in Mexican history, from 1519 to the Revolution of 1910, is the subject of the second in a series of three bilingual (Spanish-English) books designed to aid teachers in presenting the historical and cultural background of the Mexican people. The series, which lends itself to the Inquiry Method of teaching, includes illustrated…

  15. A Study of Colonial Surrogates and Indigenous Others.

    ERIC Educational Resources Information Center

    Willard, William

    1993-01-01

    Carlos Montezuma, an Apache, was raised by whites, graduated from medical school, and worked as physician for the Indian Service and Carlisle Indian School. Montezuma's life as colonial surrogate advocating "civilization" of the Indians is compared to Kafka's story of the ape who studied to become a passable European because it was "a way out" of…

  16. Pattern Formation of Bacterial Colonies by Escherichia coli

    NASA Astrophysics Data System (ADS)

    Tokita, Rie; Katoh, Takaki; Maeda, Yusuke; Wakita, Jun-ichi; Sano, Masaki; Matsuyama, Tohey; Matsushita, Mitsugu

    2009-07-01

    We have studied the morphological diversity and change in bacterial colonies, using the bacterial species Escherichia coli, as a function of both agar concentration Ca and nutrient concentration Cn. We observed various colony patterns, classified them into four types by pattern characteristics and established a morphological diagram by dividing it into four regions. They are regions A [diffusion-limited aggregation (DLA)-like], B (Eden-like), C (concentric-ring), and D (fluid-spreading). In particular, we have observed a concentric-ring colony growth for E. coli. We focused on the periodic growth in region C and obtained the following results: (i) A colony grows cyclically with the growing front repeating an advance (migration phase) and a momentary rest (consolidation phase) alternately. (ii) The growth width L and the bulge width W in one cycle decrease asymptotically to certain values, when Ca is increased. (iii) L does not depend on Cn, while W is an increasing function of Cn. Plausible mechanisms are proposed to explain the experimental results, by comparing them with those obtained for other bacterial species such as Proteus mirabilis and Bacillus subtilis.

  17. Urban Economics, Conduit-Colonialism and Public Policy

    ERIC Educational Resources Information Center

    Hamilton, Charles V.

    1972-01-01

    Considerable amounts of money already come into the cities and the black communities, but go right out as payments to absentee landlords, exploitative merchants, credit gougers, and loan sharks, as well as in support of the colonial management system. (Author/JM)

  18. Across the Colonial Divide: Conversations about Evaluation in Indigenous Contexts

    ERIC Educational Resources Information Center

    Cavino, Hayley Marama

    2013-01-01

    This essay engages questions of evaluator role and indigenous peoples participation in evaluation within colonial and decolonization contexts. Specifically, I critique the Western emphasis on cultural competence and contrast the utility of "mainstream" evaluation approaches alongside three indigenous inquiry models (Te Kotahitanga,…

  19. Assessment of density in enriched colony cages: Egg quality

    USDA-ARS?s Scientific Manuscript database

    Enriched colony cage production systems are becoming more prevalent in the US. A study was undertaken to determine the impact of housing density on hen health, well-being, egg production and quality. Six densities were examined with 8 housing replicates per density. Egg quality was assessed at hen a...

  20. Pilgrims: A Simulation of the First Year at Plymouth Colony.

    ERIC Educational Resources Information Center

    Flint, Myron

    This simulation allows students to learn about the struggle of daily life in Plymouth Colony. Students experience the hardships of life in the New World as they make decisions and face consequences as the Pilgrims did nearly 400 years ago. The unit is divided into nine phases with each phase taking approximately one hour of class time. Students…

  1. Missionary Education in Colonial Africa: The Critique of Mary Kingsley.

    ERIC Educational Resources Information Center

    Pearce, Robert

    1988-01-01

    Discussing missionary education in colonial Africa, Pearce examines the ideas of Mary Kingsley, one of the major influences on British thinking towards Africa from the late 1890's. Focusing attention on her educational views, Pearce states that she had influence on all areas of British policy in Africa, and especially West Africa. (GEA)

  2. Environmental and Genetic Determinants of Colony Morphology in Yeast

    PubMed Central

    Granek, Joshua A.; Magwene, Paul M.

    2010-01-01

    Nutrient stresses trigger a variety of developmental switches in the budding yeast Saccharomyces cerevisiae. One of the least understood of such responses is the development of complex colony morphology, characterized by intricate, organized, and strain-specific patterns of colony growth and architecture. The genetic bases of this phenotype and the key environmental signals involved in its induction have heretofore remained poorly understood. By surveying multiple strain backgrounds and a large number of growth conditions, we show that limitation for fermentable carbon sources coupled with a rich nitrogen source is the primary trigger for the colony morphology response in budding yeast. Using knockout mutants and transposon-mediated mutagenesis, we demonstrate that two key signaling networks regulating this response are the filamentous growth MAP kinase cascade and the Ras-cAMP-PKA pathway. We further show synergistic epistasis between Rim15, a kinase involved in integration of nutrient signals, and other genes in these pathways. Ploidy, mating-type, and genotype-by-environment interactions also appear to play a role in the controlling colony morphology. Our study highlights the high degree of network reuse in this model eukaryote; yeast use the same core signaling pathways in multiple contexts to integrate information about environmental and physiological states and generate diverse developmental outputs. PMID:20107600

  3. Ornithonyssus bacoti infestation and elimination from a mouse colony.

    PubMed

    Cole, Joan S; Sabol-Jones, Michelle; Karolewski, Brian; Byford, Tracylea

    2005-09-01

    Skin lesions, consisting of nonspecific bites with intense pruritus and excoriation of the skin, were found on personnel working in an animal colony primarily housing mice. The tropical rat mite, Ornithonyssus bacoti, was diagnosed from mites trapped on insect-monitoring sticky traps and collected from mouse cages in the colony. Because these mites do not live on mice but only come to feed when the animals are in their nest, an initial attempt was made to eliminate the mites with a thorough cleaning of the facility. Clidox foam was applied to the entire room with a foaming machine. Then the mice were transferred into the sanitized cages in the cleaned room. The numbers of mites were reduced to the point that they were no longer noticed in the colony, but the mites returned within 2 weeks. The mites were successfully eliminated with the use of permethrin-impregnated cotton balls in the mouse cages for 8 weeks and treatment of the premises. Treatment of the premises included spraying floors and walls of all rooms housing mice and adjacent hallways in the colony with pyrethrin spray by a commercial pest control company. To prevent one room of rabbits from maintaining the infestation, they were treated weekly with an organic pyrethrin dust. Insect sticky traps have remained negative for mites for more than 3 years after treatment.

  4. Converting insect colony waste into a potting susbstrate.

    USDA-ARS?s Scientific Manuscript database

    Rearing insect generates both a solid and semisolid waste that is generally discarded in landfills. A study was initiated to determine if the semi-solid insect colony waste product and vermiculite used in insect rearing could be combined and used as a growth substrate for plants. The semi-solid larv...

  5. Art Education in Colonial India: Implementation and Imposition

    ERIC Educational Resources Information Center

    Kantawala, Ami

    2012-01-01

    Historical inquiry in art education forms the basis of any research undertaken in the field. It is on this path that we discover ignored moments and personalities and clarify challenging ideas, thus approaching history from multiple perspectives. This historical study attempts to reframe the past of colonial Indian art education within the broader…

  6. Teaching Colonial American History: A Conceptual Interdisciplinary Approach.

    ERIC Educational Resources Information Center

    James, Michael E.

    1990-01-01

    Advocates enhancing understanding of the present through teaching about the past. Presents units of study that are concept based and interdisciplinary, focusing on life in colonial New England. Includes role play and simulation activities that highlight historical periods and provide children direct experiences. Recreates classroom life in…

  7. Reflected scatterometry for noninvasive interrogation of bacterial colonies

    USDA-ARS?s Scientific Manuscript database

    A phenotyping of bacterial colonies on agar plates using forward-scattering diffraction-pattern analysis provided promising classification of several different bacteria such as Salmonella, Vibrio, Listeria, and E. coli. Since the technique is based on forward-scattering phenomena, light transmittanc...

  8. Sensitivity analysis for simulating pesticide impacts on honey bee colonies

    EPA Science Inventory

    Background/Question/Methods Regulatory agencies assess risks to honey bees from pesticides through a tiered process that includes predictive modeling with empirical toxicity and chemical data of pesticides as a line of evidence. We evaluate the Varroapop colony model, proposed by...

  9. The View from the Veranda: Understanding Today's Colonial Student

    ERIC Educational Resources Information Center

    Ogden, Anthony

    2008-01-01

    Like the steady stream of colonial families of decades past traveling to their country's dominions abroad, contemporary education abroad students are similar passengers on a powerful steamship bound for lands of new sounds, sights and wonders. Although their studies may be challenging and demanding, students are exhilarated with thoughts of new…

  10. Colonie Interim Storage Site annual environmental report for calendar year 1991, Colonie, New York

    SciTech Connect

    Not Available

    1992-09-01

    This document describes the environmental monitoring program at the Colonie Interim Storage Site (CISS) and surrounding area, implementation of the program, and monitoring results for 1991. Environmental monitoring at CISS began in 1984 when Congress added the site to the US Department of Energy's Formerly Utilized Sites Remedial Action Program. CISS property and surrounding areas were radioactively contaminated by operations conducted by National Lead Industries, which manufactured various components from uranium and thorium from 1958 to 1984. The environmental monitoring program at CISS includes sampling networks for external gamma radiation exposure and for radium-226, thorium-232, and total uranium concentrations in surface water, sediment, and groundwater. Additionally, several nonradiological parameters are measured in groundwater. In 1992 the program will also include sampling networks for radioactive and chemical contaminants in stormwater to meet permit application requirements under the Clean Water Act. Monitoring results are compared with applicable Environmental Protection Agency (EPA) standards, DOE derived concentration guides (DCGs), dose limits, and other requirements in DOE.orders. Environmental standards are established to protect public health and the environment. Results of environmental monitoring during 1991 indicate that average concentrations of radioactive contaminants of concern were well below applicable standards and DCGS. Concentrations of some chemical contaminants in groundwater were above-the New York State Department of Environmental Conservation (Class GA) and EPA guidelines for drinking water. The potential annual radiation exposure (excluding background) calculated for a hypothetical maximally exposed individual is 0.23 mrem (milliroentgen equivalent man), which is less than an individual would receive while traveling in an airplane at 12,000 meters (39,000 feet) for one hour.

  11. Sudden deaths and colony population decline in Greek honey bee colonies.

    PubMed

    Bacandritsos, N; Granato, A; Budge, G; Papanastasiou, I; Roinioti, E; Caldon, M; Falcaro, C; Gallina, A; Mutinelli, F

    2010-11-01

    During June and July of 2009, sudden deaths, tremulous movements and population declines of adult honey bees were reported by the beekeepers in the region of Peloponnesus (Mt. Mainalo), Greece. A preliminary study was carried out to investigate these unexplained phenomena in this region. In total, 37 bee samples, two brood frames containing honey bee brood of various ages, eight sugar samples and four sugar patties were collected from the affected colonies. The samples were tested for a range of pests, pathogens and pesticides. Symptomatic adult honey bees tested positive for Varroa destructor, Nosema ceranae, Chronic bee paralysis virus (CBPV), Acute paralysis virus (ABPV), Deformed wing virus (DWV), Sacbrood virus (SBV) and Black queen cell virus (BQCV), but negative for Acarapis woodi. American Foulbrood was absent from the brood samples. Chemical analysis revealed that amitraz, thiametoxan, clothianidin and acetamiprid were all absent from symptomatic adult bees, sugar and sugar patty samples. However, some bee samples, were contaminated with imidacloprid in concentrations between 14 ng/g and 39 ng/g tissue. We present: the infection of Greek honey bees by multiple viruses; the presence of N. ceranae in Greek honey bees and the first record of imidacloprid (neonicotonoid) residues in Greek honey bee tissues. The presence of multiple pathogens and pesticides made it difficult to associate a single specific cause to the depopulation phenomena observed in Greece, although we believe that viruses and N. ceranae synergistically played the most important role. A follow-up in-depth survey across all Greek regions is required to provide context to these preliminary findings. Copyright © 2010 Elsevier Inc. All rights reserved.

  12. FluG affects secretion in colonies of Aspergillus niger.

    PubMed

    Wang, Fengfeng; Krijgsheld, Pauline; Hulsman, Marc; de Bekker, Charissa; Müller, Wally H; Reinders, Marcel; de Vries, Ronald P; Wösten, Han A B

    2015-01-01

    Colonies of Aspergillus niger are characterized by zonal heterogeneity in growth, sporulation, gene expression and secretion. For instance, the glucoamylase gene glaA is more highly expressed at the periphery of colonies when compared to the center. As a consequence, its encoded protein GlaA is mainly secreted at the outer part of the colony. Here, multiple copies of amyR were introduced in A. niger. Most transformants over-expressing this regulatory gene of amylolytic genes still displayed heterogeneous glaA expression and GlaA secretion. However, heterogeneity was abolished in transformant UU-A001.13 by expressing glaA and secreting GlaA throughout the mycelium. Sequencing the genome of UU-A001.13 revealed that transformation had been accompanied by deletion of part of the fluG gene and disrupting its 3' end by integration of a transformation vector. Inactivation of fluG in the wild-type background of A. niger also resulted in breakdown of starch under the whole colony. Asexual development of the ∆fluG strain was not affected, unlike what was previously shown in Aspergillus nidulans. Genes encoding proteins with a signal sequence for secretion, including part of the amylolytic genes, were more often downregulated in the central zone of maltose-grown ∆fluG colonies and upregulated in the intermediate part and periphery when compared to the wild-type. Together, these data indicate that FluG of A. niger is a repressor of secretion.

  13. Single-step colony assay for screening antibody libraries.

    PubMed

    Kato, Mieko; Hanyu, Yoshiro

    2017-08-10

    We describe a method, single-step colony assay, for simple and rapid screening of single-chain Fv fragment (scFv) libraries. Colonies of Escherichia coli expressing the scFv library are formed on a hydrophilic filter that is positioned in contact with a membrane coated with an antigen. scFv expression is triggered upon treatment of colonies with an induction reagent, following which scFvs are secreted from the cells and diffused to the antigen-coated membrane. scFvs that exhibit binding affinity for the antigen are captured by the membrane-immobilized antigen. Lastly, detection of scFv binding of the antigen on the membrane allows identification of the clones on the filter that express antigen-specific scFvs. We tested this methodology by using an anti-rabbit IgG scFv, scFv(A10B), and a rat immune scFv library. Experiments conducted using scFv(A10B) revealed that this method improves scFv expression during the colony assay. By using our method to screen an immune library of 3×10(3) scFv clones, we established several clones exhibiting affinity for the antigen. Moreover, we tested 7 other antigens, including peptides, and successfully identified positive clones. We believe that this simple procedure and controlled scFv expression of the single-step colony assay could make the antibody screening both rapid and reliable and lead to successful isolation of positive clones from antibody libraries. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Vimentin is necessary for colony growth of human diploid keratinocytes.

    PubMed

    Castro-Muñozledo, Federico; Velez-DelValle, Cristina; Marsch-Moreno, Meytha; Hernández-Quintero, Miriam; Kuri-Harcuch, Walid

    2015-01-01

    The role of vimentin (Vim) in diploid epithelial cells is not well known. To understand its biological function, we cultured human epidermal keratinocytes under conditions that support migration, proliferation, stratification and terminal differentiation. We identified a keratinocyte subpopulation that shows a p63(+)/α5β1(bright) phenotype and displays Vim intermediate filaments (IFs) besides their keratin IF network. These cells were mainly located at the proliferative/migratory rim of the growing colonies; but also, they were scarce and scattered or formed small groups of basal cells in confluent stratified epithelia. Stimulation of cells with EGF and wounding experiments in confluent arrested epithelia increased the number of Vim(+) keratinocytes in an extent higher to the expected for a cell population doubling. BrdU labeling demonstrated that most of the proliferative cells located at the migratory border of the colony have Vim, in contrast with proliferative cells located at the basal layer at the center of big colonies which lacked of Vim IFs, suggesting that Vim expression was not solely linked to proliferation. Therefore, we silenced Vim mRNA in the cultured keratinocytes and observed an inhibition of colony growth. Such results, together with long-term cultivation assays which showed that Vim might be associated to pattern formation in cultured epithelia, suggest that Vim expression is essential for a highly motile phenotype, which is necessary for keratinocyte colony growth and possibly for development and wound healing. Vim(+)/p63(+)/α5β1(bright) epithelial cells may play a significant physiological role in embryonic morphogenetic movements; wound healing and other pathologies such as carcinomas and hyperproliferative diseases.

  15. Caste ratios affect the reproductive output of social trematode colonies.

    PubMed

    Kamiya, T; Poulin, R

    2013-03-01

    Intraspecific phenotypic diversification in social organisms often leads to formation of physical castes which are morphologically specialized for particular tasks within the colony. The optimal caste allocation theory argues that specialized morphological castes are efficient at specific tasks, and hence different caste ratios should affect the ergonomic efficiency, hence reproductive output of the colony. However, the reproductive output of different caste ratios has been documented in few species of insects with equivocal support for the theory. This study investigated whether the ratios of nonreproductive and reproductive morphs affect the reproductive output of a recently discovered social trematode, Philophthalmus sp., in which the nonreproductive members are hypothesized to be defensive specialists. A census of natural infections and a manipulative in vitro experiment demonstrated a positive association between the reproductive output of trematode colonies and the ratio of nonreproductive to reproductive morphs in the presence of an intra-host trematode competitor, Maritrema novaezealandensis. On the contrary, without the competitor, reproductive output was negatively associated with the proportion of nonreproductive castes in colonies. Our findings demonstrate for the first time a clear fitness benefit associated with the nonreproductive castes in the presence of a competitor while illustrating the cost of maintaining such morphs in noncompetitive situations. Although the proximate mechanisms controlling caste ratio remain unclear in this trematode system, this study supports the prediction that the fitness of colonies is influenced by the composition of specialized functional morphs in social organisms, suggesting a potential for adaptive shifts of caste ratios over evolutionary time. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.

  16. The global distribution of ammonia emissions from seabird colonies

    NASA Astrophysics Data System (ADS)

    Riddick, S. N.; Dragosits, U.; Blackall, T. D.; Daunt, F.; Wanless, S.; Sutton, M. A.

    2012-08-01

    Seabird colonies represent a significant source of atmospheric ammonia (NH3) in remote maritime systems, producing a source of nitrogen that may encourage plant growth, alter terrestrial plant community composition and affect the surrounding marine ecosystem. To investigate seabird NH3 emissions on a global scale, we developed a contemporary seabird database including a total seabird population of 261 million breeding pairs. We used this in conjunction with a bioenergetics model to estimate the mass of nitrogen excreted by all seabirds at each breeding colony. The results combined with the findings of mid-latitude field studies of volatilization rates estimate the global distribution of NH3 emissions from seabird colonies on an annual basis. The largest uncertainty in our emission estimate concerns the potential temperature dependence of NH3 emission. To investigate this we calculated and compared temperature independent emission estimates with a maximum feasible temperature dependent emission, based on the thermodynamic dissociation and solubility equilibria. Using the temperature independent approach, we estimate global NH3 emissions from seabird colonies at 404 Gg NH3 per year. By comparison, since most seabirds are located in relatively cold circumpolar locations, the thermodynamically dependent estimate is 136 Gg NH3 per year. Actual global emissions are expected to be within these bounds, as other factors, such as non-linear interactions with water availability and surface infiltration, moderate the theoretical temperature response. Combining sources of error from temperature (±49%), seabird population estimates (±36%), variation in diet composition (±23%) and non-breeder attendance (±13%), gives a mid estimate with an overall uncertainty range of NH3 emission from seabird colonies of 270 [97-442] Gg NH3 per year. These emissions are environmentally relevant as they primarily occur as "hot-spots" in otherwise pristine environments with low anthropogenic

  17. Development of Age Polyethism With Colony Maturity in Coptotermes formosanus (Isoptera: Rhinotermitidae).

    PubMed

    Du, He; Chouvenc, Thomas; Su, Nan-Yao

    2017-01-09

    Age polyethism in a social insect colony occurs when individuals of different ages perform different tasks. In termites (Isoptera), it has mostly been reported in higher termites, but elements of age polyethism were recently found in juvenile colonies of a lower termite, Coptotermes formosanus Shiraki (Rhinotermitidae). The objective of this study was to compare age polyethism in immature colonies (10-mo-old) of C. formosanus to the age polyethism observed in juvenile colonies (4-yr-old), to investigate if age polyethism emerges as soon as old workers are present, or if it emerges later on, as the colony grows and ages. Age polyethism may be displayed with different patterns in immature colonies of C. formosanus when compared with juvenile colonies, owing to a difference of environmental condition within the nest, i.e., demographics and colony size. Ten-month-old colonies were observed in planar arenas and termite activities were recorded using camcorders. Larval and worker instars were determined by measuring their head width and the occurrence of behaviors was compared with behavioral data previously obtained from 4-yr-old colonies. Workers were the major workforce in both the 10-mo-old and 4-yr-old colonies. Age polyethism was minimal in 10-mo-old colonies, but was more extensive and complex in 4-yr-old colonies. Therefore, age polyethism emerges in C. formosanus as the colony matures, and may recapitulate the transition from a one-piece colony type to an extended nest colony type, with changing conditions inside the nest as the colony grows.

  18. Extreme genetic mixing within colonies of the wood-dwelling termite Kalotermes flavicollis (Isoptera, Kalotermitidae).

    PubMed

    Luchetti, A; Dedeine, F; Velonà, A; Mantovani, B

    2013-06-01

    The existence of altruism in social insects is commonly attributed to altruistic individuals gaining indirect fitness through kin selection. However, recent studies suggest that such individuals might also gain direct fitness through reproduction. Experimental studies on primitive wood-dwelling termites revealed that colony fusion often causes the death of primary reproductives (queen and king), allowing opportunities for workers to inherit the nest by developing into replacement reproductives (neotenics). Therefore, colony fusion has been proposed as an important factor that may have favoured sociality in termites. However, whether colony fusion occurs frequently in natural populations of wood-dwelling termites remains an open question. We analysed eleven colonies of the wood-dwelling termite Kalotermes flavicollis (Kalotermitidae), using two mitochondrial and five nuclear microsatellite markers. Nine of eleven colonies (82%) were mixed families, with offspring of three or more primary reproductives. To our knowledge, this result represents the highest frequency of mixed-family colonies ever reported in termites. Moreover, genetic mixing of colonies appeared extreme in two ways. First, the number of haplotypes per colony was exceptionally high (up to nine), indicating that colonies were composed of multiple queens' offspring. Second, some mixed-family colonies included individuals belonging to two highly divergent genetic lineages. F-statistics and relatedness values suggest that mixed-family colonies most likely result from colony fusion, giving support to the accelerated nest inheritance theory. These findings raise important questions about the mode of foundation of mixed-family colonies and the evolutionary forces that maintain them within populations.

  19. Rapidly Developing Yeast Microcolonies Differentiate in a Similar Way to Aging Giant Colonies

    PubMed Central

    Váchová, Libuše; Hatáková, Ladislava; Čáp, Michal; Pokorná, Michaela; Palková, Zdena

    2013-01-01

    During their development and aging on solid substrates, yeast giant colonies produce ammonia, which acts as a quorum sensing molecule. Ammonia production is connected with alkalization of the surrounding medium and with extensive reprogramming of cell metabolism. In addition, ammonia signaling is important for both horizontal (colony centre versus colony margin) and vertical (upper versus lower cell layers) colony differentiations. The centre of an aging differentiated giant colony is thus composed of two major cell subpopulations, the subpopulation of long-living, metabolically active and stress-resistant cells that form the upper layers of the colony and the subpopulation of stress-sensitive starving cells in the colony interior. Here, we show that microcolonies originating from one cell pass through similar developmental phases as giant colonies. Microcolony differentiation is linked to ammonia signaling, and cells similar to the upper and lower cells of aged giant colonies are formed even in relatively young microcolonies. A comparison of the properties of these cells revealed a number of features that are similar in microcolonies and giant colonies as well as a few that are only typical of chronologically aged giant colonies. These findings show that colony age per se is not crucial for colony differentiation. PMID:23970946

  20. High throughput and automatic colony formation assay based on impedance measurement technique.

    PubMed

    Lei, Kin Fong; Kao, Chich-Hao; Tsang, Ngan-Ming

    2017-03-02

    To predict the response of in vivo tumors, in vitro culture of cell colonies was suggested to be a standard assay to achieve high clinical relevance. To describe the responses of cell colonies, the most widely used quantification method is to count the number and size of cell colonies under microscope. That makes the colony formation assay infeasible to be high throughput and automated. In this work, in situ analysis of cell colonies suspended in soft hydrogel was developed based on impedance measurement technique. Cell colonies cultured between a pair of parallel plate electrodes were successfully analyzed by coating a layer of base hydrogel on one side of electrode. Real-time and label-free monitoring of cell colonies was realized during the culture course. Impedance magnitude and phase angle respectively represented the summation effect of colony responses and size of colonies. In addition, dynamic response of drug-treated colonies was demonstrated. High throughput and automatic colony formation assay was realized to facilitate more objective assessments in cancer research. Graphical Abstract High throughput and automatic colony formation assay was realized by in situ impedimetric analysis across a pair of parallel plate electrodes in a culture chamber. Cell colonies suspended in soft hydrogel were cultured under the tested substance and their dynamic response was represented by impedance data.

  1. Specific pathogen free macaque colonies: a review of principles and recent advances for viral testing and colony management.

    PubMed

    Yee, JoAnn L; Vanderford, Thomas H; Didier, Elizabeth S; Gray, Stanton; Lewis, Anne; Roberts, Jeffrey; Taylor, Kerry; Bohm, Rudolf P

    2016-04-01

    Specific pathogen free (SPF) macaques provide valuable animal models for biomedical research. In 1989, the National Center for Research Resources [now Office of Research Infrastructure Programs (ORIP)] of the National Institutes of Health initiated experimental research contracts to establish and maintain SPF colonies. The derivation and maintenance of SPF macaque colonies is a complex undertaking requiring knowledge of the biology of the agents for exclusion and normal physiology and behavior of macaques, application of the latest diagnostic technology, facilitiy management, and animal husbandry. This review provides information on the biology of the four viral agents targeted for exclusion in ORIP SPF macaque colonies, describes current state-of-the-art viral diagnostic algorithms, presents data from proficiency testing of diagnostic assays between laboratories at institutions participating in the ORIP SPF program, and outlines management strategies for maintaining the integrity of SPF colonies using results of diagnostic testing as a guide to decision making. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. A simple agar plate preparation for effective transfer of Ureaplasma colonies onto nitrocellulose membranes for colony immunoblotting.

    PubMed

    Zimmerman, Carl-Ulrich R; Stiedl, Thomas; Spergser, Joachim; Rosengarten, Renate

    2014-09-01

    A simple method for preparing agar plates is presented, which allows an efficient transfer of Ureaplasma colonies to nitrocellulose membranes for subsequent immunological detection. This simple and reproducible procedure was used to demonstrate antigenic variation in the phase-variable mba-locus of Ureaplasma parvum serovar 3. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Derivation of guidelines for uranium residual radioactive material in soil at the Colonie Site, Colonie, New York

    SciTech Connect

    Dunning, D.

    1996-05-01

    Residual radioactive material guidelines for uranium in soil were derived for the Colonie site located in Colonie, New York. This site has been designated for remedial action under the Formerly Utilized Sites Remedial Action Program (FUSRAP) of the U.S. Department of Energy (DOE). The site became contaminated with radioactive material as a result of operations conducted by National Lead (NL) Industries from 1958 to 1984; these activities included brass foundry operations, electroplating of metal products, machining of various components using depleted uranium, and limited work with small amounts of enriched uranium and thorium. The Colonie site comprises the former NL Industries property, now designated the Colonie Interim Storage Site (CISS), and 56 vicinity properties contaminated by fallout from airborne emissions; 53 of the vicinity properties were previously remediated between 1984 and 1988. In 1984, DOE accepted ownership of the CISS property from NL Industries. Residual radioactive material guidelines for individual radionuclides and total uranium were derived on the basis of the requirement that the 50-year committed effective dose equivalent to a hypothetical individual who lives or works in the immediate vicinity of the site should not exceed a dose of 30 mrem/yr following remedial action for the current use and likely future use scenarios or a dose of 100 mrem/yr for less likely future use scenarios. The DOE residual radioactive material guideline computer code, RESRAD, was used in this evaluation; RESRAD implements the methodology described in the DOE manual for establishing residual radioactive material guidelines.

  4. The cues of colony size: how honey bees sense that their colony is large enough to begin to invest in reproduction.

    PubMed

    Smith, Michael L; Koenig, Phoebe A; Peters, Jacob M

    2017-05-01

    As organisms develop, they first invest resources in survival and growth, but after reaching a certain condition they start to also invest in reproduction. Likewise, superorganisms, such as honey bee colonies, first invest in survival and growth, and later commit resources to reproduction once the number of workers in the colony surpasses a reproductive threshold. The first form of reproductive investment for a honey bee colony is the building of beeswax comb made of special large cells used for rearing males (drones). How do the workers sense that their colony is large enough to start building this 'drone comb'? To address this question, we experimentally increased three possible cues of colony size - worker density, volatile pheromone concentration and nest temperature - and looked for effects on the bees' comb construction. Only the colonies that experienced increased worker density were stimulated to build a higher proportion of drone comb. We then monitored and quantified potential cues in small and large colonies, to determine which cues change with colony size. We found that workers in large colonies, relative to small ones, have increased contact rates, spend more time active and experience less variable worker density. Whereas unicellular and multicellular organisms use mainly chemical cues to sense their sizes, our results suggest that at least one superorganism, a honey bee colony, uses physical cues to sense its size and thus its developmental state. © 2017. Published by The Company of Biologists Ltd.

  5. Colony-forming progenitor cells in the postnatal mouse liver and pancreas give rise to morphologically distinct insulin-expressing colonies in 3D cultures.

    PubMed

    Jin, Liang; Feng, Tao; Chai, Jing; Ghazalli, Nadiah; Gao, Dan; Zerda, Ricardo; Li, Zhuo; Hsu, Jasper; Mahdavi, Alborz; Tirrell, David A; Riggs, Arthur D; Ku, Hsun Teresa

    2014-01-01

    In our previous studies, colony-forming progenitor cells isolated from murine embryonic stem cell-derived cultures were differentiated into morphologically distinct insulin-expressing colonies. These colonies were small and not light-reflective when observed by phase-contrast microscopy (therefore termed "Dark" colonies). A single progenitor cell capable of giving rise to a Dark colony was termed a Dark colony-forming unit (CFU-Dark). The goal of the current study was to test whether endogenous pancreas, and its developmentally related liver, harbored CFU-Dark. Here we show that dissociated single cells from liver and pancreas of one-week-old mice give rise to Dark colonies in methylcellulose-based semisolid culture media containing either Matrigel or laminin hydrogel (an artificial extracellular matrix protein). CFU-Dark comprise approximately 0.1% and 0.03% of the postnatal hepatic and pancreatic cells, respectively. Adult liver also contains CFU-Dark, but at a much lower frequency (~0.003%). Microfluidic qRT-PCR, immunostaining, and electron microscopy analyses of individually handpicked colonies reveal the expression of insulin in many, but not all, Dark colonies. Most pancreatic insulin-positive Dark colonies also express glucagon, whereas liver colonies do not. Liver CFU-Dark require Matrigel, but not laminin hydrogel, to become insulin-positive. In contrast, laminin hydrogel is sufficient to support the development of pancreatic Dark colonies that express insulin. Postnatal liver CFU-Dark display a cell surface marker CD133⁺CD49f(low)CD107b(low) phenotype, while pancreatic CFU-Dark are CD133⁻. Together, these results demonstrate that specific progenitor cells in the postnatal liver and pancreas are capable of developing into insulin-expressing colonies, but they differ in frequency, marker expression, and matrix protein requirements for growth.

  6. Investigation of multimodal forward scatter phenotyping from bacterial colonies

    NASA Astrophysics Data System (ADS)

    Kim, Huisung

    A rapid, label-free, and elastic light scattering (ELS) based bacterial colony phenotyping technology, bacterial rapid detection using optical scattering technology (BARDOT) provides a successful classification of several bacterial genus and species. For a thorough understanding of the phenomena and overcoming the limitations of the previous design, five additional modalities from a bacterial colony: 3D morphology, spatial optical density (OD) distribution, spectral forward scattering pattern, spectral OD, and surface backward reflection pattern are proposed to enhance the classification/identification ratio, and the feasibilities of each modality are verified. For the verification, three different instruments: integrated colony morphology analyzer (ICMA), multi-spectral BARDOT (MS-BARDOT) , and multi-modal BARDOT (MM-BARDOT) are proposed and developed. The ICMA can measure 3D morphology and spatial OD distribution of the colony simultaneously. A commercialized confocal displacement meter is used to measure the profiles of the bacterial colonies, together with a custom built optical density measurement unit to interrogate the biophysics behind the collective behavior of a bacterial colony. The system delivers essential information related to the quantitative growth dynamics (height, diameter, aspect ratio, optical density) of the bacterial colony, as well as, a relationship in between the morphological characteristics of the bacterial colony and its forward scattering pattern. Two different genera: Escherichia coli O157:H7 EDL933, and Staphylococcus aureus ATCC 25923 are selected for the analysis of the spatially resolved growth dynamics, while, Bacillus spp. such as B. subtilis ATCC 6633, B. cereus ATCC 14579, B. thuringiensis DUP6044, B. polymyxa B719W, and B. megaterium DSP 81319, are interrogated since some of the Bacillus spp. provides strikingly different characteristics of ELS patterns, and the origin of the speckle patterns are successfully correlated with

  7. A child of the empire: British sociology and colonialism, 1940s-1960s.

    PubMed

    Steinmetz, George

    2013-01-01

    British sociology was established as an academic discipline between 1945 and 1965, just as the British Empire was gearing up for a new phase of developmental colonialism backed by the social and other sciences. Many parts of the emerging sociological discipline became entangled with colonialism. Key themes and methods in sociology and the staff of sociology departments emerged from this colonial context. Historians have tended to place postwar British sociology in the context of expanding higher education and the welfare state, and have overlooked this colonial constellation. The article reconstructs this forgotten moment of disciplinary founding and explores three of the factors that promoted colonial sociology: the Colonial Social Science Research Council, the so-called Asquith universities, and the social research institutes in the colonies; and the involvement of sociologists from the London School of Economics in training colonial officials. © 2013 Wiley Periodicals, Inc.

  8. Reproductive effects of nest-marking studies in an American white pelican colony

    USGS Publications Warehouse

    Boellstorff, D.E.; Anderson, D.W.; Ohlendorf, H.M.; O'Neill, E.J.

    1988-01-01

    In 1981 and 1982 we studied the reproductive success of American White Pelicans in the Klamath Basin of northern California. We observed that reproductive success at one colony became reduced in 1981 when we entered that colony to collect eggs for chemical analysis and to mark nests for an assessment of nesting success. Those pelicans produced only 0.5 Y/N contrasted to pelicans nesting at an undisturbed colony that produced about 1.2 Y/N. No colonies were entered in 1982 and both produced about 1.1 Y/N. We concluded that our activities reduced the success of that one disturbed colony. We suggest that the sample-egg technique should not be used in American White Pelican colonies, in-colony activities should be very limited, and researchers in bird colonies should attempt more often to assess the effects of their own activiites

  9. DISSECTING COLONY DEVELOPMENT OF NEUROSPORA CRASSA USING mRNA PROFILING AND COMPARTATIVE GENOMICS APPROACHES

    USDA-ARS?s Scientific Manuscript database

    Colony development, which includes hyphal extension, branching, anastomosis and asexual sporulation are fundamental aspects of the lifecycle of filamentous fungi; genetic mechanisms underlying these phenomena are poorly understood. We conducted transcriptional profiling during colony development of...

  10. Effects of a fipronil spot treatment on field colonies of Coptotermes formosanus (Isoptera: Rhinotermitidae).

    PubMed

    Osbrink, W L A; Cornelius, M L; Showler, A T; Pound, J M

    2014-04-01

    This field study investigated the colony effect of a fipronil spot treatment applied to active infestations of Formosan subterranean termite, Coptotermes formosanus Shiraki. Spot treatments were applied to a single active independent monitor from each of four colonies in which multiple independent monitors were established. All treated monitors were abandoned, and the contents of the treated monitors were replaced with untreated wood at the approximately 30-d posttreatment inspection. All colonies survived treatment and only one colony exhibited long-term effects, which included significant reductions in termite collections and increased worker size. The affected colony was treated within 1 m of its primary nest. Two colonies exhibited a correlation between monitor termite production and distance from treatment. Distance appears to be a factor limiting fipronil's colony effects. The Formosan subterranean termite may not be a good candidate for the exterior perimeter and localized interior treatment label option because of the large range and size of the colony.

  11. Breeding colonies of least terns (Sternula antillarum) in northern Sonora, Mexico, 2006-2008

    USGS Publications Warehouse

    Rosemartin, Alyssa; van Riper, Charles

    2012-01-01

    We document distribution of breeding least terns (Sternula antillarum) in northern Sonora, Mexico, 2006-2008. We report breeding activity at six sites with active colonies, including three previously undocumented colonies.

  12. Effect of Gravity on the Colonial Morphology of Staphylococci in Soft Agar

    PubMed Central

    Wilkins, Judd R.; Hatten, Mary B.; Salmirs, Seymour

    1969-01-01

    After horizontal rotation on a clinostat at 1 rev/min, subsurface colonies of staphylococci in soft agar were compact and spherical; nonrotated colonies were diffuse and elongated. Images PMID:5369302

  13. Geographic structure of adelie penguin populations: overlap in colony-specific foraging areas

    USGS Publications Warehouse

    Ainley, D.G.; Ribic, C.A.; Ballard, G.; Heath, S.; Gaffney, I.; Karl, B.J.; Barton, K.J.; Wilson, P.R.; Webb, S.

    2004-01-01

    In an investigation of the factors leading to geographic structuring among Ade??lie Penguin (Pygoscelis adeliae) populations, we studied the size and overlap of colony-specific foraging areas within an isolated cluster of colonies. The study area, in the southwestern Ross Sea, included one large and three smaller colonies, ranging in size from 3900 to 135000 nesting pairs, clustered on Ross and Beaufort Islands. We used triangulation of radio signals from transmitters attached to breeding penguins to determine foraging locations and to define colony-specific foraging areas during the chick-provisioning period of four breeding seasons, 1997-2000. Colony populations (nesting pairs) were determined using aerial photography just after egg-laying; reproductive success was estimated by comparing ground counts of chicks fledged to the number of breeding pairs apparent in aerial photos. Foraging-trip duration, meal size, and adult body mass were estimated using RFID (radio frequency identification) tags and an automated reader and weighbridge. Chick growth was assessed by weekly weighing. We related the following variables to colony size: foraging distance, area, and duration; reproductive success; chick meal size and growth rate; and seasonal variation in adult body mass. We found that penguins foraged closest to their respective colonies, particularly at the smaller colonies. However, as the season progressed, foraging distance, duration, and area increased noticeably, especially at the largest colony. The foraging areas of the smaller colonies overlapped broadly, but very little foraging area overlap existed between the large colony and the smaller colonies, even though the foraging area of the large colony was well within range of the smaller colonies. Instead, the foraging areas of the smaller colonies shifted as that of the large colony grew. Colony size was not related to chick meal size, chick growth, or parental body mass. This differed from the year previous to

  14. Colony forming cell (CFC) assay for human hematopoietic cells.

    PubMed

    Sarma, Nayan J; Takeda, Akiko; Yaseen, Nabeel R

    2010-12-18

    Human hematopoietic stem/progenitor cells are usually obtained from bone marrow, cord blood, or peripheral blood and are used to study hematopoiesis and leukemogenesis. They have the capacity to differentiate into lymphoid and myeloid lineages. The colony forming cell (CFC) assay is used to study the proliferation and differentiation pattern of hematopoietic progenitors by their ability to form colonies in a semisolid medium. The number and the morphology of the colonies formed by a fixed number of input cells provide preliminary information about the ability of progenitors to differentiate and proliferate. Cells can be harvested from individual colonies or from the whole plate to further assess their numbers and differentiation states using flow cytometry and morphologic evaluation of Giemsa-stained slides. This assay is useful for assessing myeloid but not lymphoid differentiation. The term myeloid in this context is used in its wider sense to encompass granulocytic, monocytic, erythroid, and megakaryocytic lineages. We have used this assay to assess the effects of oncogenes on the differentiation of primary human CD34+ cells derived from peripheral blood. For this purpose cells are transduced with either control retroviral construct or a construct expressing the oncogene of interest, in this case NUP98-HOXA9. We employ a commonly used retroviral vector, MSCV-IRES-GFP, that expresses a bicistronic mRNA that produces the gene of interest and a GFP marker. Cells are pre-activated by growing in the presence of cytokines for two days prior to retroviral transduction. After another two days, GFP+ cells are isolated by fluorescence-activated cell sorting (FACS) and mixed with a methylcellulose-containing semisolid medium supplemented with cytokines and incubated till colonies appear on the surface, typically 14 days. The number and morphology of the colonies are documented. Cells are then removed from the plates, washed, counted, and subjected to flow cytometry and

  15. Parasites and Pathogens of the Honeybee (Apis mellifera) and Their Influence on Inter-Colonial Transmission.

    PubMed

    Forfert, Nadège; Natsopoulou, Myrsini E; Frey, Eva; Rosenkranz, Peter; Paxton, Robert J; Moritz, Robin F A

    2015-01-01

    Pathogens and parasites may facilitate their transmission by manipulating host behavior. Honeybee pathogens and pests need to be transferred from one colony to another if they are to maintain themselves in a host population. Inter-colony transmission occurs typically through honeybee workers not returning to their home colony but entering a foreign colony ("drifting"). Pathogens might enhance drifting to enhance transmission to new colonies. We here report on the effects infection by ten honeybee viruses and Nosema spp., and Varroa mite infestation on honeybee drifting. Genotyping of workers collected from colonies allowed us to identify genuine drifted workers as well as source colonies sending out drifters in addition to sink colonies accepting them. We then used network analysis to determine patterns of drifting. Distance between colonies in the apiary was the major factor explaining 79% of drifting. None of the tested viruses or Nosema spp. were associated with the frequency of drifting. Only colony infestation with Varroa was associated with significantly enhanced drifting. More specifically, colonies with high Varroa infestation had a significantly enhanced acceptance of drifters, although they did not send out more drifting workers. Since Varroa-infested colonies show an enhanced attraction of drifting workers, and not only those infected with Varroa and its associated pathogens, infestation by Varroa may also facilitate the uptake of other pests and parasites.

  16. Parasites and Pathogens of the Honeybee (Apis mellifera) and Their Influence on Inter-Colonial Transmission

    PubMed Central

    Frey, Eva; Rosenkranz, Peter; Paxton, Robert J.; Moritz, Robin F. A.

    2015-01-01

    Pathogens and parasites may facilitate their transmission by manipulating host behavior. Honeybee pathogens and pests need to be transferred from one colony to another if they are to maintain themselves in a host population. Inter-colony transmission occurs typically through honeybee workers not returning to their home colony but entering a foreign colony (“drifting”). Pathogens might enhance drifting to enhance transmission to new colonies. We here report on the effects infection by ten honeybee viruses and Nosema spp., and Varroa mite infestation on honeybee drifting. Genotyping of workers collected from colonies allowed us to identify genuine drifted workers as well as source colonies sending out drifters in addition to sink colonies accepting them. We then used network analysis to determine patterns of drifting. Distance between colonies in the apiary was the major factor explaining 79% of drifting. None of the tested viruses or Nosema spp. were associated with the frequency of drifting. Only colony infestation with Varroa was associated with significantly enhanced drifting. More specifically, colonies with high Varroa infestation had a significantly enhanced acceptance of drifters, although they did not send out more drifting workers. Since Varroa-infested colonies show an enhanced attraction of drifting workers, and not only those infected with Varroa and its associated pathogens, infestation by Varroa may also facilitate the uptake of other pests and parasites. PMID:26451849

  17. Bionomics and formation of "Bonsai" colonies with long term rearing of Coptotermes formosanus (Isoptera: Rhinotermitidae)

    USDA-ARS?s Scientific Manuscript database

    This laboratory study reports the ability of Formosan subterranean termite, Coptotermes formosanus Shiraki, colonies to survive for at least 9-yr while restricted to a sweater box. Colonies survived by limiting queen size and worker numbers, allowing these bonsai colonies to thrive. Queen physogastr...

  18. Improved Technique for Identification and Enumeration of Methanogenic Bacterial Colonies on Roll Tubes by Epifluorescence Microscopy

    PubMed Central

    Kataoka, Naoaki; Tokiwa, Yutaka; Takeda, Kiyoshi

    1991-01-01

    Methanogenic fluorescent colonies can be clearly identified on roll tubes by using an epifluorescence microscope equipped with a × 2 objective. Methanogenic and nonmethanogenic colonies could be counted in roll tubes prepared from methanogenic enrichment cultures. Late-developing colonies appearing after 25 days of incubation were mainly methanogenic. PMID:16348613

  19. Qur'anic and "Ajami" Literacies in Pre-Colonial West Africa

    ERIC Educational Resources Information Center

    Diallo, Ibrahima

    2012-01-01

    Traditional African literacy practices have often been ignored in the wake of European colonialism and the educational policies of colonial governments. Nonetheless, literacy had been established in parts of Africa following the introduction of Islam. This paper will examine the developments of literacy in pre-colonial West Africa. In this region,…

  20. Political Life in Eighteenth-Century Virginia. Essays from Colonial Williamsburg. The Foundations of America.

    ERIC Educational Resources Information Center

    Greene, Jack P.

    This book explores the history of the Virginia colony from the early 18th century to the time of the signing of the Declaration of Independence. Virginia, the oldest and most prosperous of Great Britain's North American colonies, assumed a leading role in the political life of the colonies. Some in 17th century Virginia had seen political…

  1. Creating Germans Abroad: White Education and the Colonial Condition in German Southwest Africa, 1894-1914

    ERIC Educational Resources Information Center

    Walther, Daniel Joseph

    2013-01-01

    From the perspective of German colonial supporters and authorities, appropriate white education in the settler colony of Southwest Africa (SWA) was essential for maintaining German hegemony in the territory. In order to reach this objective, the German colonial administration in SWA, with assistance from pedagogues and institutions in Germany,…

  2. Response of mountain plovers to plague-driven dynamics of black-tailed prairie dog colonies

    USDA-ARS?s Scientific Manuscript database

    Sylvatic plague is a major factor influencing prairie dog colony dynamics in the western Great Plains. We studied the nesting response of the mountain plover (Charadrius montanus), a grassland bird that nests on prairie dog colonies, to plague-driven dynamics of prairie dog colonies at three sites i...

  3. Distribution species abundance and nesting site use of Atlantic coast colonies of herons and their allies

    USGS Publications Warehouse

    Custer, T.W.; Osborn, R.G.; Stout, W.F.

    1980-01-01

    In 1975 and 1976, 8 teams of investigators located 262 colonies of nesting herons and their allies along the Atlantic coast from Florida to Maine [USA]. Fourteen species [Ajaia ajaja, Plegadis falcinellus, Nycticorax nycticorax, Ardea herodias, Eudocimus albus, Egretta thula, Hydranassa tricolor, Bubulcus ibis, Casmerodius albus, Butorides striatus, Florida caerulea, Dichromanassa rufescens, Nyctanassa violacea and Mycteria americana] were found in Florida, numbers decreasing to 7 in Maine. Colonies censused in the extreme south and north of the study area were lower in number of species and number of adults than those in the intermediate area. More than 90% of the colony sites surveyed in 1975 were active in 1976. The total number of nesting adults per colony, number of species per colony and number of nesting adults of each species per colony in 1976 were significantly correlated with their respective values for 1975. Abandoned and new colonies may be satellites of nearby reused colonies; they had fewer individuals and species than reused colonies and were closer to reused colonies than reused colonies were to each other. [This study was part of an attempt to examine colonially nesting herons as biological indicators of environmental quality.

  4. Globalization as Continuing Colonialism: Critical Global Citizenship Education in an Unequal World

    ERIC Educational Resources Information Center

    Mikander, Pia

    2016-01-01

    In an unequal world, education about global inequality can be seen as a controversial but necessary topic for social science to deal with. Even though the world no longer consists of colonies and colonial powers, many aspects of the global economy follow the same patterns as during colonial times, with widening gaps between the world's richest and…

  5. Biotic interactions mediate the influence of bird colonies on vegetation and soil chemistry at aggregation sites.

    PubMed

    Natusch, Daniel James Deans; Lyons, Jessica Ann; Brown, Gregory P; Shine, Richard

    2017-02-01

    Colonial-nesting organisms can strongly alter the chemical and biotic conditions around their aggregation sites, with cascading impacts on other components of the ecosystem. In tropical Australia, Metallic Starlings (Aplonis metallica) nest in large colonies far above the forest canopy, in emergent trees. The ground beneath those trees is open, in stark contrast to the dense foliage all around. We surveyed the areas beneath 27 colony trees (and nearby randomly chosen trees lacking bird colonies) to quantify the birds' impacts on soil and vegetation characteristics, and to test alternative hypotheses about the proximate mechanisms responsible for the lack of live vegetation beneath colony trees. Nutrient levels were greatly elevated beneath colony trees (especially, those with larger colonies), potentially reaching levels toxic to older trees. However, seedlings thrived in the soil from beneath colony trees. The primary mechanism generating open areas beneath colony trees is disturbance by scavengers (feral pigs and native Turkeys) that are attracted in vast numbers to these nutrient hotspots. Seedlings flourished within exclosures inaccessible to vertebrate herbivores, but were rapidly consumed if unprotected. Our results contrast with previous studies of colonies of seabirds on remote islands, where a lack of large terrestrial herbivores results in bird colonies encouraging rather than eliminating vegetation in areas close to the nesting site. In our continental study system, scavengers may rapidly dilute the spatial heterogeneity generated by the massive nutrient subsidy from bird colonies.

  6. Population dynamics of Varroa destructor (Acari: Varroidae) in commercial honey bee colonies and implications for control

    USDA-ARS?s Scientific Manuscript database

    Treatment schedules to maintain low levels of Varroa mites in honey bee colonies were tested in hives started from either package bees or splits of larger colonies. The schedules were developed based on predictions of Varroa population growth generated from a mathematical model of honey bee colony ...

  7. [The National Museum of Chilean Medicine: I. The Colonial period].

    PubMed

    Cruz-Coke, R

    1989-09-01

    The first museum of Chilean Medicines was founded by Dr Enrique Laval in 1955. The new museum is a fusion of this one and patrimony of the School of Medicine and the ancient San Vicente Hospital. It was created in 1987 by the present Dean, Aleksandar Goic. The present article describes one of the halls, the Colony. Pictures of Governors and Conquerors who founded the first hospitals are in display. The period of Religious Medicine (1616-1823) is represented by pictures and religious objects, as well as hospital utensils. The times of the University of San Felipe and the "Protomedicato" (1756-1839) includes pictures and documentation from the first colonial physicians. Chilean medicine at that time stayed at a medieval level, lacking the influence of the Renaissance, the Barroque and other movements enlighting european medicine.

  8. Water extraction on Mars for an expanding human colony.

    PubMed

    Ralphs, M; Franz, B; Baker, T; Howe, S

    2015-11-01

    In-situ water extraction is necessary for an extended human presence on Mars. This study looks at the water requirements of an expanding human colony on Mars and the general systems needed to supply that water from the martian atmosphere and regolith. The proposed combination of systems in order to supply the necessary water includes a system similar to Honeybee Robotics' Mobile In-Situ Water Extractor (MISWE) that uses convection, a system similar to MISWE but that directs microwave energy down a borehole, a greenhouse or hothouse type system, and a system similar to the Mars Atmospheric Resource Recovery System (MARRS). It is demonstrated that a large water extraction system that can take advantage of large deposits of water ice at site specific locations is necessary to keep up with the demands of a growing colony. Copyright © 2015 The Committee on Space Research (COSPAR). Published by Elsevier Ltd. All rights reserved.

  9. Writing sex and sexuality: archives of colonial North India.

    PubMed

    Gupta, Charu

    2011-01-01

    This article focuses on disparate sites and subjects to reflect on and problematize the relationship between sexuality and the archives in colonial north India. I dwell on how ‘recalcitrant’ and hidden histories of sexuality can be gleaned by not only expanding our arenas of archives, but also by decentering and recasting colonial archives. I do so by specifically investigating some of the “indigenous” writings in Hindi, through texts concerning homosexuality, sex manuals, the writings of a woman ayurvedic practitioner, didactic literature and its relationship to Dalit (outcaste) sexuality, and current popular Dalit literature and its representations of the past. The debate for me here is not about the flaws of archival uses but rather of playing one archive against another, of appropriating many parallel, alternative, official, and popular archives simultaneously to shape a more nuanced and layered understanding of sexuality.

  10. The Piano, the animus, and the colonial experience.

    PubMed

    Izod, J

    1996-01-01

    Focused principally on an analysis of Ada, the mute heroine of Jane Campion's The Piano, this article shows how post-Jungian animus theory illuminates that character's mysterious personality. In particular, Ann Ulanov's thoughts about animus development are connected with Demaris Wehr's observations concerning the internalization of social oppression in an argument that shows how, notwithstanding she is a woman, Ada is a product of colonial oppression. Her mythological antecedents are also considered, and are particularly marked in that she resembles the handless maiden in Marie-Louise von Franz's analysis of that fairy tale. In this context Ada's ultimate renunciation of her husband is symbolically reinforced by the developing personality of her daughter Flora. The changes in both characters can be seen as implying not only the rebirth of Ada's psyche but also the emergence of a new psychological readiness to throw off the colonial mantle.

  11. Modal parameters estimation using ant colony optimisation algorithm

    NASA Astrophysics Data System (ADS)

    Sitarz, Piotr; Powałka, Bartosz

    2016-08-01

    The paper puts forward a new estimation method of modal parameters for dynamical systems. The problem of parameter estimation has been simplified to optimisation which is carried out using the ant colony system algorithm. The proposed method significantly constrains the solution space, determined on the basis of frequency plots of the receptance FRFs (frequency response functions) for objects presented in the frequency domain. The constantly growing computing power of readily accessible PCs makes this novel approach a viable solution. The combination of deterministic constraints of the solution space with modified ant colony system algorithms produced excellent results for systems in which mode shapes are defined by distinctly different natural frequencies and for those in which natural frequencies are similar. The proposed method is fully autonomous and the user does not need to select a model order. The last section of the paper gives estimation results for two sample frequency plots, conducted with the proposed method and the PolyMAX algorithm.

  12. Macrophage colony-stimulating factor induces indirect angiogenesis in vivo.

    PubMed

    Phillips, G D; Aukerman, S L; Whitehead, R A; Knighton, D R

    1993-01-01

    The cytokine macrophage colony-stimulating factor was implanted in the rabbit cornea over a wide dose range (1 ng to 100 microg) to assay its angiogenic activity in vivo. Neovascularization occurred in a dose-dependent manner, and maximum angiogenesis occurred only with 100 microg. Histologic analysis revealed that the corneas were free of inflammation at the lower doses, but had slight inflammation at 50 and 100 microg. Nonspecific esterase staining of frozen sections and transmission electron microscopy revealed that the inflammatory cells were predominantly macrophages, with very few neutrophils present. This association of capillary formation with inflammation suggests an indirect mechanism of angiogenesis. The lack of neutrophils within the inflammatory cell infiltrate demonstrates that indirect angiogenesis can proceed without the local presence of neutrophils. This distinguishes macrophage colony-stimulating factor from other indirect-acting angiogenesis factors that have been identified to date.

  13. Response Ant Colony Optimization of End Milling Surface Roughness

    PubMed Central

    Kadirgama, K.; Noor, M. M.; Abd Alla, Ahmed N.

    2010-01-01

    Metal cutting processes are important due to increased consumer demands for quality metal cutting related products (more precise tolerances and better product surface roughness) that has driven the metal cutting industry to continuously improve quality control of metal cutting processes. This paper presents optimum surface roughness by using milling mould aluminium alloys (AA6061-T6) with Response Ant Colony Optimization (RACO). The approach is based on Response Surface Method (RSM) and Ant Colony Optimization (ACO). The main objectives to find the optimized parameters and the most dominant variables (cutting speed, feedrate, axial depth and radial depth). The first order model indicates that the feedrate is the most significant factor affecting surface roughness. PMID:22294914

  14. Random mitotic activities across human embryonic stem cell colonies.

    SciTech Connect

    Jin, Q.; Duggan, R.; Dasa, S.; Li, F.; Chen, L.

    2010-08-01

    A systemic and quantitative study was performed to examine whether different levels of mitotic activities, assessed by the percentage of S-phase cells at any given time point, existed at different physical regions of human embryonic stem (hES) cell colonies at 2, 4, 6 days after cell passaging. Mitotically active cells were identified by the positive incorporation of 5-bromo-2-deoxyuridine (BrdU) within their newly synthesized DNA. Our data indicated that mitotically active cells were often distributed as clusters randomly across the colonies within the examined growth period, presumably resulting from local deposition of newly divided cells. This latter notion was further demonstrated by the confined growth of enhanced green florescence protein (EGFP) expressing cells amongst non-GFP expressing cells. Furthermore, the overall percentage of mitotically active cells remained constantly at about 50% throughout the 6-day culture period, indicating mitotic activities of hES cell cultures were time-independent under current growth conditions.

  15. Task scheduling based on ant colony optimization in cloud environment

    NASA Astrophysics Data System (ADS)

    Guo, Qiang

    2017-04-01

    In order to optimize the task scheduling strategy in cloud environment, we propose a cloud computing task scheduling algorithm based on ant colony algorithm. The main goal of this algorithm is to minimize the makespan and the total cost of the tasks, while making the system load more balanced. In this paper, we establish the objective function of the makespan and costs of the tasks, define the load balance function. Meanwhile, we also improve the initialization of the pheromone, the heuristic function and the pheromone update method in the ant colony algorithm. Then, some experiments were carried out on the Cloudsim platform, and the results were compared with algorithms of ACO and Min-Min. The results shows that the algorithm is more efficient than the other two algorithms in makespan, costs and system load balancing.

  16. High fertility of Old Colony Mennonites in Mexico.

    PubMed

    Felt, J C; Ridley, J C; Allen, G; Redekop, C

    1990-10-01

    Old Colony Mennonites in Mexico appear to demonstrate natural fertility, using no form of artificial birth control and apparently not attempting to limit family size. The resulting fertility is nearly as high as that of the Hutterites, although the Mennonites lack the communal economic system of the latter. Most Mennonites in Mexico migrated from Canada in the 1920s, and the largest single settlement, called the Manitoba Colony, is one of four in the state of Chihuahua. A 1967 partial census obtained data from 38% of the Mennonite households. Family size in the sample was close to that in a local survey taken in the same year. Available church records matched with census forms permitted verification of and corrections to 560 female reproductive histories. The median number of live births to women over age 45 years was 9.5, compared with 10.4 in the Hutterites. Age-specific marital fertility rates and birth intervals closely resembled those of the Hutterites.

  17. Transatlantic abundance of the N2-fixing colonial cyanobacterium Trichodesmium.

    PubMed

    Davis, Cabell S; McGillicuddy, Dennis J

    2006-06-09

    Colonial diazotrophic cyanobacteria of the genus Trichodesmium are thought to play a significant role in the input of new nitrogen to upper layers of the tropical and subtropical oceanic ecosystems that cover nearly half of Earth's surface. Here we describe results of a transatlantic survey in which a noninvasive underwater digital microscope (the video plankton recorder), was towed across the North Atlantic at 6 meters per second while undulating between the surface and 130 meters. Colony abundance had a basin-scale trend, a clear association with anticyclonic eddies, and was not affected by hurricane-forced mixing. Subsurface abundance was higher than previously reported, which has important implications for the global ocean nitrogen cycle.

  18. Feeding flights of nesting wading birds at a Virginia colony

    USGS Publications Warehouse

    Erwin, R.M.

    1984-01-01

    Feeding flights of Snowy Egrets (Egretta thula), Tricolored Herons (E. tricolor), Little Blue Herons (E. caerulea), and Cattle Egrets (Bubulcus ibis) were monitored at a small nesting colony near Chincoteague, Virginia during late May and June 1979. All four species varied their flight directions over a series of days. Cattle Egrets oriented in a different direction (toward uplands) from the other three wetland-feeding species, which oriented toward Spartina marsh areas. None of the species showed a tendency to form groups while departing from or arriving at the colony. Tide level had little influence on flight directions used. Comparisons are made between these results and those from a similar study in coastal North Carolina.

  19. A Hybrid Ant Colony Algorithm for Loading Pattern Optimization

    NASA Astrophysics Data System (ADS)

    Hoareau, F.

    2014-06-01

    Electricité de France (EDF) operates 58 nuclear power plant (NPP), of the Pressurized Water Reactor (PWR) type. The loading pattern (LP) optimization of these NPP is currently done by EDF expert engineers. Within this framework, EDF R&D has developed automatic optimization tools that assist the experts. The latter can resort, for instance, to a loading pattern optimization software based on ant colony algorithm. This paper presents an analysis of the search space of a few realistic loading pattern optimization problems. This analysis leads us to introduce a hybrid algorithm based on ant colony and a local search method. We then show that this new algorithm is able to generate loading patterns of good quality.

  20. Water extraction on Mars for an expanding human colony

    NASA Astrophysics Data System (ADS)

    Ralphs, M.; Franz, B.; Baker, T.; Howe, S.

    2015-11-01

    In-situ water extraction is necessary for an extended human presence on Mars. This study looks at the water requirements of an expanding human colony on Mars and the general systems needed to supply that water from the martian atmosphere and regolith. The proposed combination of systems in order to supply the necessary water includes a system similar to Honeybee Robotics' Mobile In-Situ Water Extractor (MISWE) that uses convection, a system similar to MISWE but that directs microwave energy down a borehole, a greenhouse or hothouse type system, and a system similar to the Mars Atmospheric Resource Recovery System (MARRS). It is demonstrated that a large water extraction system that can take advantage of large deposits of water ice at site specific locations is necessary to keep up with the demands of a growing colony.

  1. Improved Clonal Selection Algorithm Combined with Ant Colony Optimization

    NASA Astrophysics Data System (ADS)

    Gao, Shangce; Wang, Wei; Dai, Hongwei; Li, Fangjia; Tang, Zheng

    Both the clonal selection algorithm (CSA) and the ant colony optimization (ACO) are inspired by natural phenomena and are effective tools for solving complex problems. CSA can exploit and explore the solution space parallely and effectively. However, it can not use enough environment feedback information and thus has to do a large redundancy repeat during search. On the other hand, ACO is based on the concept of indirect cooperative foraging process via secreting pheromones. Its positive feedback ability is nice but its convergence speed is slow because of the little initial pheromones. In this paper, we propose a pheromone-linker to combine these two algorithms. The proposed hybrid clonal selection and ant colony optimization (CSA-ACO) reasonably utilizes the superiorities of both algorithms and also overcomes their inherent disadvantages. Simulation results based on the traveling salesman problems have demonstrated the merit of the proposed algorithm over some traditional techniques.

  2. Space Colony from a Commercial Asteroid Mining Company Town

    NASA Astrophysics Data System (ADS)

    Taylor, Thomas C.; Grandl, Werner; Pinni, Martina; Benaroya, Haym

    2008-01-01

    Commercial mining towns on Earth become cities. Company towns need commerce to drive the growth and economy of early space colonies. Water is an early resource for camp consumables plus propellant export sales from asteroid mining operations at proposed burned out comets with water methane ice cores for sustainable growth over 50 years, financed from profits and capable with affordable logistics to support resource recovery. One co-author's perspective includes remote resource recovery sites on Earth. Other co-authors' experiences include architecture, lunar habitation, and architectural space colony concepts. This paper combines these experiences to propose commercial opportunities possible as mankind moves beyond one planet. Alaska's North Slope commercial history indicates that different multiple logistics transportation systems are required to reduce the risk to humans and families moved in before the oil flowed. Commercial enterprises have risked $20 billion and spent hundreds of billions in private money after profits were created. The lessons learned are applied to a burned out comet designated Wilson-Harrington (1979) and explores the architecture for early living within the burned out comet disk created from ice recovery and later sealed with an expected methane ice interior. Considered is the recovery of the resources, the transport of water back to Earth orbit or L-1, plus later the development of more comfortable space colony living. Commercial markets produce cities on Earth and the same can happen on Space Colonies. The key is an ``in place'' affordable commercial logistics system that can service, stimulate and sustain a 50-year commercial propellant market.

  3. Microfermentation Series for Identification of Single Colonies of Enterobacteriaceae

    PubMed Central

    Huhtanen, C. N.; Naghski, J.; Dellamonica, E. S.

    1972-01-01

    Microfermentation tests for members of the family Enterobacteriaceae were devised by using agar solutions in disposable, multi-welled, plastic trays. The tests could be made directly from isolated colonies picked from agar plates and represented a considerable saving in time, labor, and materials over the conventional methods. Tests were formulated for determining carbohydrate fermentations, citrate utilization, motility, amino acid decarboxylation, and production of H2S, indole, urease, and acetyl-methyl-carbinol. PMID:4564046

  4. Generation of a Specific-Pathogen–Free Baboon Colony

    PubMed Central

    Wolf, Roman F; Eberle, Richard; White, Gary L

    2010-01-01

    We undertook establishing an SPF baboon colony in response to requests from researchers. To enable the widest possible future use of SPF baboons, our aim was to develop an SPF colony of baboons (Papio hamadryas anubis) free of 12 target viruses: 5 herpesviruses, 4 retroviruses, simian virus 40, measles, and monkeypox. Infant baboons were removed from their mothers within 24 h of birth and nursery-reared. Groups of 3 to 8 age-matched conspecifics were isolated in separate rooms for 1 y while undergoing repeated testing for target viruses. During the initial 7 y of the SPF program, 171 infants were enrolled, of which 76 (44.4%) subsequently were removed from the program. Of those removed, 54 (71.0%) were culled due to breaks in virus-free status, 12 (15.8%) died of various causes, 4 (5.3%) developed seizures, and 6 (7.9%) were removed for other reasons. The most problematic viruses were baboon cytomegalovirus (25.9% of culls), Herpesvirus papio 1 (51.9%), and simian foamy virus (7.4%). Using conspecific groups of 3 to 4 infants reduced first-year program losses as compared with groups of 6 to 8. There have been 17 births in the SPF colony, and all these infants have been free of all target viruses since birth. On the basis of these results, early removal of infants from their dams, housing in small peer groups, frequent virus testing, and aggressive culling of virus-positive animals is an effective approach for development of a baboon colony free of multiple viruses. PMID:21205446

  5. Enterococcus faecium small colony variant endocarditis in an immunocompetent patient

    PubMed Central

    Egido, S. Hernández; Ruiz, M. Siller; Inés Revuelta, S.; García, I. García; Bellido, J.L. Muñoz

    2015-01-01

    Small colony variants (SCV) are slow-growing subpopulations of bacteria usually associated with auxotrophism, causing persistent or recurrent infections. Enterococcus faecalis SCV have been seldom described, and only one case of Enterococcus faecium SCV has been reported, associated with sepsis in a leukaemia patient. Here we report the first case described of bacteraemia and endocarditis by SCV E. faecium in an immunocompetent patient. PMID:26862434

  6. Vasa and the germ line lineage in a colonial urochordate.

    PubMed

    Rosner, Amalia; Moiseeva, Elizabeth; Rinkevich, Yuval; Lapidot, Ziva; Rinkevich, Baruch

    2009-07-15

    Germ cell sequestering in Animalia is enlightened by either, launching true germ line along epigenetic or preformistic modes of development, or by somatic embryogenesis, where no true germ line is set aside. The research on germ line-somatic tissue segregation is of special relevancy to colonial organisms like botryllid ascidians that reconstruct, on a weekly basis, completely new sets of male and female gonads in newly formed somatic tissues. By sequencing and evaluating expression patterns of BS-Vasa, the Botryllus schlosseri orthologue of Vasa, in sexually mature and asexual colonies during blastogenesis, we have demonstrated that the BS-Vasa mRNA and protein are not expressed exclusively in germ cell lineages, but appeared in cells repeatedly emerging de novo in the colony, independently of its sexual state. In addition, we recorded an immediate Vasa response to cellular stress (UV irradiation) indicating additional functions to its germ line assignments. To confirm germ lineage exclusivity, we examined the expression of three more stem cell markers (BS-Pl10, Bl-piwi and Oct4). Vasa co-expression with Pl10 and Oct4 was detected in germ line derivatives and with Bl-piwi in somatic tissues. Presumptive primordial germ cells (PGC-like cells), that are Vasa(+)/Pl10(+)/Oct4(+) and 6-12 microm in diameter, were first detected in wrapped-tail embryos, in oozooids, in sexual/asexual colonies, within a newly identified PGC niche termed as 'budlet niche', and in circulating blood borne cells, indicating epigenetic embryogenesis. Alternatively, BS-Vasa co-expression with piwi orthologue, an omnipresent bona fide stemness flag, in non germ line cell populations, may indicate germ cell neogenesis (somatic embryogenesis) in B. schlosseri. Both alternatives are not necessarily mutually exclusive.

  7. Improved ant colony algorithm and its simulation study

    NASA Astrophysics Data System (ADS)

    Wang, Zongjiang

    2013-03-01

    Ant colony algorithm is development a new heuristic algorithm through simulation ant foraging. For its convergence rate slow, easy to fall into local optimal solution proposed for the adjustment of key parameters, pheromone update to improve the way and through the issue of TSP experiments, results showed that the improved algorithm has better overall search capabilities and demonstrated the feasibility and effectiveness of this method.

  8. Research on the ant colony algorithm in robot path planning

    NASA Astrophysics Data System (ADS)

    Wang, Yong; Ma, Jianming; Wang, Ying

    2017-05-01

    Using the A* algorithm principle proposed adaptive adjustment heuristic function, to reduce the degree of divergence algorithm; The state transition of the next ant improvement strategies, to improve the diversity of path planning solution; Control the change of the pheromone, to avoid algorithm trapped in local optimal solution; The improved ant colony algorithm makes the robot along an optimal or suboptimal path to arrive at the target.

  9. Protein structure optimization with a "Lamarckian" ant colony algorithm.

    PubMed

    Oakley, Mark T; Richardson, E Grace; Carr, Harriet; Johnston, Roy L

    2013-01-01

    We describe the LamarckiAnt algorithm: a search algorithm that combines the features of a "Lamarckian" genetic algorithm and ant colony optimization. We have implemented this algorithm for the optimization of BLN model proteins, which have frustrated energy landscapes and represent a challenge for global optimization algorithms. We demonstrate that LamarckiAnt performs competitively with other state-of-the-art optimization algorithms.

  10. Disease control during the colonial period in Australia.

    PubMed

    Turner, A J

    2011-07-01

    The first permanent European settlers of Australia arrived in 1788 to establish a penal colony at Sydney, New South Wales (NSW). As the colony grew and wool production increased, more free settlers and emancipists developed farming in inland Australia. During the 1840s veterinarians commenced arriving in small numbers but they were not closely associated with the development and execution of disease control programs, which was left to lay inspectors of stock. The arrival of William Tyson Kendall and coordinated action with Graham Mitchell led to the establishment of a private veterinary college following the passage of veterinary surgeons legislation in Victoria. From this time, veterinarians came to be appointed to positions formerly occupied by lay inspectors and the veterinary profession was able to take up the role of planning and executing government-led disease control programs. From a colony relying on wool for export to the UK, technical advancements in meat freezing and pasture improvement widened the range and increased the quantity of exported products. Before the advent of veterinary advances, sheep scab was eradicated, a vaccine was developed for anthrax and glanders infection of horses was prevented entry to Australia. Graduates from the Melbourne Veterinary College spread across Australia and in this period a conservative quarantine policy was developed following inaction to control an outbreak of contagious bovine pleuropneumonia (CBPP) and the escape of rabbits to form a plague across the continent. Coordinated control of CBPP had to await the next century and advancement of technology increased our understanding of bacteriology and immunity of infectious diseases. Veterinary services were provided to the militia sent by the colonies to the Boer Wars in South Africa 1987-1901 and the veterinarians from Victoria were led by an Australian trained veterinarian. © 2011 The Author. Australian Veterinary Journal © 2011 Australian Veterinary Association.

  11. C. V. Raman and Colonial Physics: Acoustics and the Quantum

    NASA Astrophysics Data System (ADS)

    Banerjee, Somaditya

    2014-06-01

    Presenting the social and historical context of Chandrasekhara Venkata Raman, this paper clarifies the nature and development of his work in early twentieth-century colonial India. Raman's early fascination with acoustics became the basis of his later insights into the nature of the light quantum. His work on light scattering played an important role in the experimental verification of quantum mechanics. In general, Raman's worldview corrects certain Orientalist stereotypes about scientific practice in Asia.

  12. Deconvolving molecular signatures of interactions between microbial colonies

    PubMed Central

    Harn, Y.-C.; Powers, M. J.; Shank, E. A.; Jojic, V.

    2015-01-01

    Motivation: The interactions between microbial colonies through chemical signaling are not well understood. A microbial colony can use different molecules to inhibit or accelerate the growth of other colonies. A better understanding of the molecules involved in these interactions could lead to advancements in health and medicine. Imaging mass spectrometry (IMS) applied to co-cultured microbial communities aims to capture the spatial characteristics of the colonies’ molecular fingerprints. These data are high-dimensional and require computational analysis methods to interpret. Results: Here, we present a dictionary learning method that deconvolves spectra of different molecules from IMS data. We call this method MOLecular Dictionary Learning (MOLDL). Unlike standard dictionary learning methods which assume Gaussian-distributed data, our method uses the Poisson distribution to capture the count nature of the mass spectrometry data. Also, our method incorporates universally applicable information on common ion types of molecules in MALDI mass spectrometry. This greatly reduces model parameterization and increases deconvolution accuracy by eliminating spurious solutions. Moreover, our method leverages the spatial nature of IMS data by assuming that nearby locations share similar abundances, thus avoiding overfitting to noise. Tests on simulated datasets show that this method has good performance in recovering molecule dictionaries. We also tested our method on real data measured on a microbial community composed of two species. We confirmed through follow-up validation experiments that our method recovered true and complete signatures of molecules. These results indicate that our method can discover molecules in IMS data reliably, and hence can help advance the study of interaction of microbial colonies. Availability and implementation: The code used in this paper is available at: https://github.com/frizfealer/IMS_project. Contact: vjojic@cs.unc.edu Supplementary

  13. Improved Aerobic Colony Count Technique for Hydrophobic Grid Membrane Filters

    PubMed Central

    Parrington, Lorna J.; Sharpe, Anthony N.; Peterkin, Pearl I.

    1993-01-01

    The AOAC International official action procedure for performing aerobic colony counts on hydrophobic grid membrane filters (HGMFs) uses Trypticase soy-fast green FCF agar (FGA) incubated for 48 h. Microbial growths are various shades of green on a pale green background, which can cause problems for automated as well as manual counting. HGMFs which had been incubated 24 or 48 h at 35°C on Trypticase soy agar were flooded underneath with 1 to 2 ml of 0.1% triphenyltetrazolium chloride (TTC) solution by simply lifting one corner of the filter while it was still on the agar and adding the reagent. Microbial growths on HGMFs were counted after color had been allowed to develop for 15 min at room temperature. With representative foods, virtually all colonies stained pink to red. Automated electronic counts made by using the MI-100 HGMF Interpreter were easier and more reliable than control HGMF counts made by the AOAC International official action procedure. Manual counting was easier as well because of increased visibility of the microbial growths. Except in the case of dairy products, 24-h TTC counts did not differ significantly from 48-h FGA counts, whereas the FGA counts at 24 h were always significantly lower, indicating that for many food products the HGMF TTC flooding method permits aerobic colony counts to be made after 24 h. PMID:16349033

  14. Improved aerobic colony count technique for hydrophobic grid membrane filters.

    PubMed

    Parrington, L J; Sharpe, A N; Peterkin, P I

    1993-09-01

    The AOAC International official action procedure for performing aerobic colony counts on hydrophobic grid membrane filters (HGMFs) uses Trypticase soy-fast green FCF agar (FGA) incubated for 48 h. Microbial growths are various shades of green on a pale green background, which can cause problems for automated as well as manual counting. HGMFs which had been incubated 24 or 48 h at 35 degrees C on Trypticase soy agar were flooded underneath with 1 to 2 ml of 0.1% triphenyltetrazolium chloride (TTC) solution by simply lifting one corner of the filter while it was still on the agar and adding the reagent. Microbial growths on HGMFs were counted after color had been allowed to develop for 15 min at room temperature. With representative foods, virtually all colonies stained pink to red. Automated electronic counts made by using the MI-100 HGMF Interpreter were easier and more reliable than control HGMF counts made by the AOAC International official action procedure. Manual counting was easier as well because of increased visibility of the microbial growths. Except in the case of dairy products, 24-h TTC counts did not differ significantly from 48-h FGA counts, whereas the FGA counts at 24 h were always significantly lower, indicating that for many food products the HGMF TTC flooding method permits aerobic colony counts to be made after 24 h.

  15. Scanning Electron Microscopy of Colonies of Six Species of Candida

    PubMed Central

    Joshi, K. R.; Wheeler, E. E.; Gavin, J. B.

    1973-01-01

    Thirty strains of six species of Candida isolated from patients were cultured for 60 h on Sabouraud agar, freeze-dried, and examined with a scanning electron microscope. The colonies were circular (Candida albicans, C. guilliermondii) or oval (C. tropicalis, C. pseudotropicalis, C. krusei, C. parakrusei) in outline, and those of C. pseudotropicalis and C. krusei had an irregular outline due to a peripheral pseudomycelium. The morphology of individual microorganisms was examined at the margins and apex of those species which lacked a surface coat (C. pseudotropicalis, C. krusei, C. parakrusei, C. guilliermondii), and through cracks in the surface coating of those which showed a surface coat (C. albicans, C. tropicalis). All species showed buds, bud scars, and interconnecting intercellular processes, but were generally spherical (C. albicans, C. tropicalis) or ovoid (C. pseudotropicalis, C. krusei, C. parakrusei, C. guilliermondii) in fixed preparations. In unfixed material, individual organisms were almost invariably indented. Fixation with 3% glutaraldehyde and washing before freeze-drying caused partial removal of the surface coating of colonies of C. albicans and C. tropicalis, which persisted only as irregular sheets or as a filamentous meshwork. This filamentous meshwork was also present among the organisms of colonies of C. albicans, C. tropicalis, and C. pseudotropicalis. It is concluded that these filaments represent the precipitation or unmasking of some component of the intercellular matrix of these organisms. Images PMID:4197906

  16. Controlling biofouling caused by the colonial hydroid Cordylophora caspia.

    PubMed

    Folino-Rorem, Nadine C; Indelicato, Jennifer

    2005-07-01

    The euryhaline hydroid, Cordylophora caspia, causes fouling problems in Europe and the United States. Researchers propose that this hydroid is becoming more prevalent in freshwater habitats as evidenced in Morris, IL where it was found clogging intake pipes and screens at a power plant, Midwest Generation's Collins Station. Our objective was to determine ways to curtail growth or kill C. caspia. Hydroid colonies in the laboratory were exposed to thermal treatments of 35, 36.1, 37.7, and 40.5 degrees C ranging from 1 to 8h. Hydroids did not survive at the two highest temperatures. Colonies exposed to lower temperatures exhibited varying degrees of survival relative to temperature and exposure time and demonstrated regeneration. In addition, experiments using chlorine were conducted using concentrations ranging from 0.2 to 5.0 mgl(-1). Chlorine experiments using exposure times of 105 min and three 20 min exposures in a 24h period did not kill colonies but were effective in curtailing growth. Thermal treatments are preferred because they are effective and result in less environmental impact in receiving waters than chemicals.

  17. Rationality in collective decision-making by ant colonies.

    PubMed

    Edwards, Susan C; Pratt, Stephen C

    2009-10-22

    Economic models of animal behaviour assume that decision-makers are rational, meaning that they assess options according to intrinsic fitness value and not by comparison with available alternatives. This expectation is frequently violated, but the significance of irrational behaviour remains controversial. One possibility is that irrationality arises from cognitive constraints that necessitate short cuts like comparative evaluation. If so, the study of whether and when irrationality occurs can illuminate cognitive mechanisms. We applied this logic in a novel setting: the collective decisions of insect societies. We tested for irrationality in colonies of Temnothorax ants choosing between two nest sites that varied in multiple attributes, such that neither site was clearly superior. In similar situations, individual animals show irrational changes in preference when a third relatively unattractive option is introduced. In contrast, we found no such effect in colonies. We suggest that immunity to irrationality in this case may result from the ants' decentralized decision mechanism. A colony's choice does not depend on site comparison by individuals, but instead self-organizes from the interactions of multiple ants, most of which are aware of only a single site. This strategy may filter out comparative effects, preventing systematic errors that would otherwise arise from the cognitive limitations of individuals.

  18. Rationality in collective decision-making by ant colonies

    PubMed Central

    Edwards, Susan C.; Pratt, Stephen C.

    2009-01-01

    Economic models of animal behaviour assume that decision-makers are rational, meaning that they assess options according to intrinsic fitness value and not by comparison with available alternatives. This expectation is frequently violated, but the significance of irrational behaviour remains controversial. One possibility is that irrationality arises from cognitive constraints that necessitate short cuts like comparative evaluation. If so, the study of whether and when irrationality occurs can illuminate cognitive mechanisms. We applied this logic in a novel setting: the collective decisions of insect societies. We tested for irrationality in colonies of Temnothorax ants choosing between two nest sites that varied in multiple attributes, such that neither site was clearly superior. In similar situations, individual animals show irrational changes in preference when a third relatively unattractive option is introduced. In contrast, we found no such effect in colonies. We suggest that immunity to irrationality in this case may result from the ants’ decentralized decision mechanism. A colony's choice does not depend on site comparison by individuals, but instead self-organizes from the interactions of multiple ants, most of which are aware of only a single site. This strategy may filter out comparative effects, preventing systematic errors that would otherwise arise from the cognitive limitations of individuals. PMID:19625319

  19. Sexual and asexual reproduction in the colonial ascidian Botryllus schlosseri.

    PubMed

    Gasparini, Fabio; Manni, Lucia; Cima, Francesca; Zaniolo, Giovanna; Burighel, Paolo; Caicci, Federico; Franchi, Nicola; Schiavon, Filippo; Rigon, Francesca; Campagna, Davide; Ballarin, Loriano

    2015-01-01

    The colonial tunicate Botryllus schlosseri is a widespread filter-feeding ascidian that lives in shallow waters and is easily reared in aquaria. Its peculiar blastogenetic cycle, characterized by the presence of three blastogenetic generations (filtering adults, buds, and budlets) and by recurrent generation changes, has resulted in over 60 years of studies aimed at understanding how sexual and asexual reproduction are coordinated and regulated in the colony. The possibility of using different methodological approaches, from classical genetics to cell transplantation, contributed to the development of this species as a valuable model organism for the study of a variety of biological processes. Here, we review the main studies detailing rearing, staging methods, reproduction and colony growth of this species, emphasizing the asymmetry in sexual and asexual reproduction potential, sexual reproduction in the field and the laboratory, and self- and cross-fertilization. These data, opportunely matched with recent tanscriptomic and genomic outcomes, can give a valuable help to the elucidation of some important steps in chordate evolution. © 2014 Wiley Periodicals, Inc.

  20. A Burkholderia pseudomallei Colony Variant Necessary for Gastric Colonization

    PubMed Central

    Austin, C. R.; Goodyear, A. W.; Bartek, I. L.; Stewart, A.; Sutherland, M. D.; Silva, E. B.; Zweifel, A.; Vitko, N. P.; Tuanyok, A.; Highnam, G.; Mittelman, D.; Keim, P.; Schweizer, H. P.; Vázquez-Torres, A.; Dow, S. W. C.

    2015-01-01

    ABSTRACT  Diverse colony morphologies are a hallmark of Burkholderia pseudomallei recovered from infected patients. We observed that stresses that inhibit aerobic respiration shifted populations of B. pseudomallei from the canonical white colony morphotype toward two distinct, reversible, yet relatively stable yellow colony variants (YA and YB). As accumulating evidence supports the importance of B. pseudomallei enteric infection and gastric colonization, we tested the response of yellow variants to hypoxia, acidity, and stomach colonization. Yellow variants exhibited a competitive advantage under hypoxic and acidic conditions and alkalized culture media. The YB variant, although highly attenuated in acute virulence, was the only form capable of colonization and persistence in the murine stomach. The accumulation of extracellular DNA (eDNA) was a characteristic of YB as observed by 4′,6-diamidino-2-phenylindole (DAPI) staining of gastric tissues, as well as in an in vitro stomach model where large amounts of eDNA were produced without cell lysis. Transposon mutagenesis identified a transcriptional regulator (BPSL1887, designated YelR) that when overexpressed produced the yellow phenotype. Deletion of yelR blocked a shift from white to the yellow forms. These data demonstrate that YB is a unique B. pseudomallei pathovariant controlled by YelR that is specifically adapted to the harsh gastric environment and necessary for persistent stomach colonization. PMID:25650400

  1. Genetic analysis of mutagenesis in aging Escherichia coli colonies.

    PubMed

    Taddei, F; Halliday, J A; Matic, I; Radman, M

    1997-10-01

    Bacteria live in unstructured and structured environments, experiencing feast and famine lifestyles. Bacterial colonies can be viewed as model structured environments. SOS induction and mutagenesis have been observed in aging Escherichia coli colonies, in the absence of exogenous sources of DNA damage. This cAMP-dependent mutagenesis occurring in Resting Organisms in a Structured Environment (ROSE) is unaffected by a umuC mutation and therefore differs from both targeted UV mutagenesis and recA730 (SOS constitutive) untargeted mutagenesis. As a recB mutation has only a minor effect on ROSE mutagenesis it also differs from both adaptive reversion of the lacI33 allele and from iSDR (inducible Stable DNA Replication) mutagenesis. Besides its recA and lexA dependence, ROSE mutagenesis is also uvrB and polA dependent. These genetic requirements are reminiscent of the untargeted mutagenesis in lambda phage observed when unirradiated lambda infects UV-irradiated E. coli. These mutations, which are not observed in aging liquid cultures, accumulate linearly with the age of the colonies. ROSE mutagenesis might offer a good model for bacterial mutagenesis in structured environments such as biofilms and for mutagenesis of quiescent eukaryotic cells.

  2. Education, democracy and colonial transition the case of Hong Kong

    NASA Astrophysics Data System (ADS)

    Bray, Mark; Lee, W. O.

    1993-11-01

    Among the main features of the decolonisation process in Africa, Asia and the South Pacific were widespread efforts by colonial authorities to introduce democratic forms of government. These efforts sought to prepare the territories for selfgovernment and independence. In Hong Kong, the colonial era is coming to an end later than in other sizeable territories in the world, and the transition will not be to independence but to a Special Administrative Region of the People's Republic of China. This transition is planned to take place in 1997. Nevertheless, in the twilight of the colonial era the authorities are making strong efforts to promote democracy, and see the education system as an important instrument to help achieve this goal. This paper analyses the case of Hong Kong within the context of comparative literature, and shows how the Hong Kong experience requires adaptation of existing theories. It addresses both macro-level and school-level initiatives, and discusses the extent to which education is a useful instrument to achieve the overall objective.

  3. Colonial modern skeletal change in the U.S.A.

    PubMed

    Angel, J L

    1976-11-01

    Eighty-two people dating from 1975 to 1879 compared with 182 modern middle-class White and Black skeletons test the myths of radical changes produced by improved diet, less disease, and nineteenth century immigration. Longevity increases and health and growth improvement is clearest in reduced juvenile deaths (census data) and deepening of true pelvis. Stature increase is minimal (though seventeenth century Londoners and modern West Africans are shorter than Colonial to Modern Americans); teeth deteriorate and for cultural reasons fractures increase. Clavicles and forearms elongate. From Old to New World Colonial samples there is a noticeable skull change (and a greater Old World to Modern contrast) but White Colonial to Modern shows strong continuity surprisingly, the key changes being increasing head height, and retraction of face with increasing nose projection, and longer mastoids, resulting from selection and mixture. Blacks change more, possibly from Indian and White mixture. Variabilities are above average. Change is much less than expected, and apparently involves heterosis and selection as well as the obvious health advance and mixtures.

  4. Cocktail-party effect in king penguin colonies

    PubMed Central

    Aubin, T.; Jouventin, P.

    1998-01-01

    The king penguin, Aptenodytes patagonicus, breeds without a nest in colonies of several thousands of birds. To be fed, the chick must recognize the parents in a particularly noisy environment using only vocal cues. The call an adult makes when seeking the chick is emitted at a high amplitude level. Nevertheless, it is transmitted in a colonial context involving the noise generated by the colony and the screening effect of the bodies, both factors reducing the signal-to-noise ratio. In addition, the adult call is masked by a background noise with similar amplitude and spectral and temporal characteristics, enhancing the difficulty for the chick in finding its parents. We calculate that the maximum distance from the caller at which its signal can be differentiated from the background noise (signal-to-noise ratio equal to 1) should not exceed 8 to 9 m in a feeding area. But our tests show that, in fact, chicks can discriminate between the parental call and calls from other adults at a greater distance, even when call intensity is well below that of the noise of simultaneous calls produced by other adults. This capacity to perceive and extract the call of the parent from the ambient noise and particularly from the calls of other adults, termed the 'cocktail-party effect' in speech intelligibility tests, enhances the chick's ability to find its parents.

  5. ``Campo del Cielo'' Meteorites: Astronomical Heritage and Cultural Colonialism

    NASA Astrophysics Data System (ADS)

    López, Alejandro Martín; Altman, Agustina

    2012-09-01

    In the province of Chaco, Argentina, there is a very unique dispersion of metallic meteorites called ``Campo del Cielo''. One of the meteoric fragments of this dispersion, the meteorite called ``El Chaco'', consisting of 37 tons, is the second heaviest in the world. These meteorites are of great importance to the worldview of the Moqoit, aboriginal people that inhabit this region. For the local Creole population the meteorites are also relevant, that's why they have being cited in numerous documents and reports since the colonial period. During the first months of 2012, two Argentine artists and the Artistic Director of the German contemporary art exhibition called dOCUMENTA (13) tried to move ``El Chaco'' meteorite to Germany in order to exhibit it as an artistic object. Due to the fact that moving the meteorite could have a negative impact according to the Moqoit cosmology and that they were not able to participate in the decision they begun a manifestation against the movement of El Chaco. The opposition made by aboriginal communities and experts in cultural astronomy was able to stop the transfer. The whole process and its impact on the local community have promoted a deep discussion about art, science and cultural colonialism. In this paper we aim to address this debate and its consequences. This will allow us to think about contemporary forms of colonialism that are hidden in many scientific and artistic projects. Furthermore, we aim to debate about the most effective ways of protecting astronomical heritage in the Third World.

  6. Epidemics and public health in early colonial Somaliland.

    PubMed

    Mohamed, J

    1999-02-01

    The early colonial period in the Somaliland Protectorate was marked by the intrusion of new 'colonial' epidemics and diseases, such as smallpox, cholera, influenza, venereal diseases, tuberculosis, relapsing fever and the decline of the population. The aetiology of the diseases was social. They were introduced into the country through the movement of imperial armies and displaced people, the improvement in transportation and the integration of the country into the British Empire. The protectorate administration attempted to control the epidemics. However, since the medical staff and medical facilities were thin on the ground, the effect of the medical campaigns were limited. Not all the medical campaigns were a 'mirage', however. Medical campaigns played an important role in the control of venereal diseases, particularly syphilis. Overall, the incidence of epidemics declined from 1937 onwards. The cause was again social and had very little to do with medical campaigns. The ending of the campaigns of conquest, the massive movement of armies and people and the development of relative stability in the country played a key and decisive role in the decline in the incidence of diseases. The aetiology of colonial epidemics and their decline had both socio-political origins and explanations. The article deals with that neglected aspect of the history of Somaliland.

  7. Infectious disease research investments follow colonial ties: questionable ethics.

    PubMed

    Fitchett, Joseph R; Head, Michael G; Atun, Rifat

    2014-03-01

    International funding for global health research is not systematically documented. We have assessed the level of research funding awarded by UK funders of international research to low- and middle-income countries or research institutions in these countries. We analysed 6165 studies; from these we selected 522 that matched our criteria and used them to evaluate research funding by pathogen, disease, research and development value chain, funding organisation and country. Investment in infectious disease research in the countries studied totalled £264 million. Distribution of research investments closely mirrored that of the UK's former colonial territories; the top five countries, and eight of the top 10, have historical links with the UK, being current or former members of the Commonwealth of Nations. HIV, malaria and neglected tropical diseases attracted the greatest investment (£219 million; 82.8%), with most studies focussing on operational and epidemiological research (£109 million; 41.3%). International financing of infectious disease research by UK funding organisations follows former colonial ties. Funding institutions should review their funding policies to ensure that they also assist low- and middle-income countries without colonial ties to address their disease burden. A global investment surveillance system is needed to map and monitor funding for international research and guide the allocation of scarce resources to reduce the global disease burden.

  8. Autolysis and autoaggregation in Pseudomonas aeruginosa colony morphology mutants.

    PubMed

    D'Argenio, David A; Calfee, M Worth; Rainey, Paul B; Pesci, Everett C

    2002-12-01

    Two distinctive colony morphologies were noted in a collection of Pseudomonas aeruginosa transposon insertion mutants. One set of mutants formed wrinkled colonies of autoaggregating cells. Suppressor analysis of a subset of these mutants showed that this was due to the action of the regulator WspR and linked this regulator (and the chemosensory pathway to which it belongs) to genes that encode a putative fimbrial adhesin required for biofilm formation. WspR homologs, related in part by a shared GGDEF domain, regulate cell surface factors, including aggregative fimbriae and exopolysaccharides, in diverse bacteria. The second set of distinctive insertion mutants formed colonies that lysed at their center. Strains with the most pronounced lysis overproduced the Pseudomonas quinolone signal (PQS), an extracellular signal that interacts with quorum sensing. Autolysis was suppressed by mutation of genes required for PQS biosynthesis, and in one suppressed mutant, autolysis was restored by addition of synthetic PQS. The mechanism of autolysis may involve activation of the endogenous prophage and phage-related pyocins in the genome of strain PAO1. The fact that PQS levels correlated with autolysis suggests a fine balance in natural populations of P. aeruginosa between survival of the many and persistence of the few.

  9. Colony disassociation following diet partitioning in a unicolonial ant

    NASA Astrophysics Data System (ADS)

    Silverman, J.; Liang, D.

    2001-01-01

    Discriminating nestmates from alien conspecifics via chemical cues is recognized as a critical element in maintaining the integrity of insect societies. We determined, in laboratory experiments, that nestmate recognition in an introduced population of the Argentine ant, Linepithema humile, is modified by hydrocarbons acquired from insect prey, and that workers from spatially isolated colony fragments, each provided with prey that possessed distinct cuticular hydrocarbons, displayed aggressive behavior towards their former nestmates. Isolation for 28 days or more between colony fragments fed different prey was sufficient to prevent re-establishment of inter-nest communication for at least an additional 28 days through the introduction of a bridge between the nests. Ants possessed intrinsic cuticular hydrocarbons plus only those hydrocarbons from the prey they received during the isolation period. Colony fragments which were isolated for less than 28 days reunited with workers possessing both prey hydrocarbons. Therefore, L. humile nestmate recognition may be dynamic, being in part dependent on the spatio-temporal distribution of prey, along with physical factors permitting or restricting access of subcolony units to those prey.

  10. German Water Infrastructure in China: Colonial Qingdao 1898-1914.

    PubMed

    Kneitz, Agnes

    2016-12-01

    Within the colorful tapestry of colonial possessions the German empire acquired over the short period of its existence, Qingdao stands out because it fulfilled a different role from settlements in Africa-especially because of its exemplary planned water infrastructure: its technological model, the resulting (public) hygiene, and the adjunct brewery. The National Naval Office (Reichsmarineamt), which oversaw the administration of the future "harbour colony"-at first little more than a little fishing village-enjoyed a remarkable degree of freedom in implementing this project. The German government invested heavily in showing off its techno-cultural achievements to China and the world and thereby massively exploited the natural resources of the mountainous interior. This contribution focuses on Qingdao's water infrastructure and its role in public hygiene and further area development. This article will not only use new empirical evidence to demonstrate that the water infrastructure was an ambivalent "tool of empire". Relying on the concept of "urban metabolism," this paper primarily traces the ecological consequences, particularly the landscape transformation of the mountains surrounding the bay and the implications for the region's water resources. When evaluating colonial enterprises, changes in local ecology should play a significantly greater role.

  11. Towards a colony counting system using hyperspectral imaging

    NASA Astrophysics Data System (ADS)

    Masschelein, B.; Robles-Kelly, A.; Blanch, C.; Tack, N.; Simpson-Young, B.; Lambrechts, A.

    2012-03-01

    Colony counting is a procedure used in microbiology laboratories for food quality monitoring, environmental management, etc. Its purpose is to detect the level of contamination due to the presence and growth of bacteria, yeasts and molds in a given product. Current automated counters require a tedious training and setup procedure per product and bacteria type and do not cope well with diversity. This contrasts with the setting at microbiology laboratories, where a wide variety of food and bacteria types have to be screened on a daily basis. To overcome the limitations of current systems, we propose the use of hyperspectral imaging technology and examine the spectral variations induced by factors such as illumination, bacteria type, food source and age and type of the agar. To this end, we perform experiments making use of two alternative hyperspectral processing pipelines and compare our classification results to those yielded by color imagery. Our results show that colony counting may be automated through the automatic recovery of the illuminant power spectrum and reflectance. This is consistent with the notion that the recovery of the illuminant should minimize the variations in the spectra due to reflections, shadows and other photometric artifacts. We also illustrate how, with the reflectance at hand, the colonies can be counted making use of classical segmentation and classification algorithms.

  12. Random walk models of worker sorting in ant colonies.

    PubMed

    Sendova-Franks, Ana B; Van Lent, Jan

    2002-07-21

    Sorting can be an important mechanism for the transfer of information from one level of biological organization to another. Here we study the algorithm underlying worker sorting in Leptothorax ant colonies. Worker sorting is related to task allocation and therefore to the adaptive advantages associated with an efficient system for the division of labour in ant colonies. We considered four spatially explicit individual-based models founded on two-dimensional correlated random walk. Our aim was to establish whether sorting at the level of the worker population could occur with minimal assumptions about the behavioural algorithm of individual workers. The behaviour of an individual worker in the models could be summarized by the rule "move if you can, turn always". We assume that the turning angle of a worker is individually specific and negatively dependent on the magnitude of an internal parameter micro which could be regarded as a measure of individual experience or task specialization. All four models attained a level of worker sortedness that was compatible with results from experiments onLeptothorax ant colonies. We found that the presence of a sorting pivot, such as the nest wall or an attraction force towards the centre of the worker population, was crucial for sorting. We make a distinction between such pivots and templates and discuss the biological implications of their difference.

  13. [Antigen-binding clone cells in hematopoietic spleen colonies].

    PubMed

    Khazanova, I V; Van'ko, L V; Malaĭtsev, V V; Khamitova, N S; Zhuravel', G M

    1976-05-01

    The antigen-binding cell clones and the Ig-positive cells were found and quantitatively assessed in the primary hemopoietic splenic colonies. The data ogtained were analyzed assuming that the ratio of clone of specialized B-cells should reflect the quantitative ration in the corresponding V-genes in the given lymphocyte populations at definite stages of its development. The colonies differed from one another markedly by the curves of inhibition by DNP-lysine of rosette-formation with DNP-erythrocytes, i.e. by the avidity of B-cells of the given specificity. The colonies differed significantly by the ratio of the volumes of the two clone groups (cell with anti-DNP and anti-BE Ig-receptors) between themselves and the combination of the Ig-positive cells. These quantitaive regularities were incompatible with the view that each B-cell had any conceivable set of V-genes, i.e. with the germ-line hypothesis of the antibody and receptor diversity.

  14. Lubricating bacteria model for branching growth of bacterial colonies

    NASA Astrophysics Data System (ADS)

    Kozlovsky, Yonathan; Cohen, Inon; Golding, Ido; Ben-Jacob, Eshel

    1999-06-01

    Various bacterial strains (e.g., strains belonging to the genera Bacillus, Paenibacillus, Serratia, and Salmonella) exhibit colonial branching patterns during growth on poor semisolid substrates. These patterns reflect the bacterial cooperative self-organization. A central part of the cooperation is the collective formation of a lubricant on top of the agar which enables the bacteria to swim. Hence it provides the colony means to advance towards the food. One method of modeling the colonial development is via coupled reaction-diffusion equations which describe the time evolution of the bacterial density and the concentrations of the relevant chemical fields. This idea has been pursued by a number of groups. Here we present an additional model which specifically includes an evolution equation for the lubricant excreted by the bacteria. We show that when the diffusion of the fluid is governed by a nonlinear diffusion coefficient, branching patterns evolve. We study the effect of the rates of emission and decomposition of the lubricant fluid on the observed patterns. The results are compared with experimental observations. We also include fields of chemotactic agents and food chemotaxis and conclude that these features are needed in order to explain the observations.

  15. Computational Analysis of Flow Field Inside Coral Colony

    NASA Astrophysics Data System (ADS)

    Hossain, Md Monir; Staples, Anne

    2015-11-01

    Development of the flow field inside coral colonies is a key issue for understanding coral natural uptake, photosynthesis and wave dissipation capabilities. But most of the computations and experiments conducted earlier, measured the flow outside the coral reef canopies. Experimental studies are also constrained due to the limitation of measurement techniques and limited environmental conditions. Numerical simulations can be an answer to overcome these shortcomings. In this work, a detailed, three-dimensional simulation of flow around a single coral colony was developed to examine the interaction between coral geometry and hydrodynamics. To simplify grid generation and minimize computational cost, Immersed Boundary method (IBM) was implemented. The computation of IBM involves identification of the interface between the solid body and the fluid, establishment of the grid/interface relation and identification of the forcing points on the grid and distribution of the forcing function on the corresponding points. LES was chosen as the framework to capture the turbulent flow field without requiring extensive modeling. The results presented will give insight into internal coral colony flow fields and the interaction between coral and surrounding ocean hydrodynamics.

  16. Multifractality in individual honeybee behavior hints at colony-specific social cascades: Reanalysis of radio-frequency identification data from five different colonies

    NASA Astrophysics Data System (ADS)

    Carver, Nicole S.; Kelty-Stephen, Damian G.

    2017-02-01

    Honeybees (Apis mellifera) exhibit complex coordination and interaction across multiple behaviors such as swarming. This coordination among honeybees in the same colony is remarkably similar to the concept of informational cascades. The multifractal geometry of cascades suggests that multifractal measures of individual honeybee activity might carry signatures of these colony-wide coordinations. The present work reanalyzes time stamps of entrances to and exits from the hive captured by radio-frequency identification (RFID) sensors reading RFID tags on individual bees. Indeed, both multifractal spectrum width for individual bees' inter-reading interval series and differences of those widths from surrogates significantly predicted not just whether the individual bee's hive had a mesh enclosure but also predicted the specific membership of individual bees in one of five colonies. The significant effects of multifractality in matching honeybee activity to type of colony and, further, matching individual honeybees to their exact home colony suggests that multifractality quantifies key features of the colony-wide interactions across many scales. This relevance of multifractality to predicting colony type or colony membership adds additional credence to the cascade metaphor for colony organization. Perhaps, multifractality provides a new tool for exploring the relationship between individual organisms and larger, more complex social behaviors.

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

    PubMed Central

    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. PMID:26465750

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

    PubMed

    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.

  19. Mechanisms of social regulation change across colony development in an ant

    PubMed Central

    2010-01-01

    Background Mutual policing is an important mechanism for reducing conflict in cooperative groups. In societies of ants, bees, and wasps, mutual policing of worker reproduction can evolve when workers are more closely related to the queen's sons than to the sons of workers or when the costs of worker reproduction lower the inclusive fitness of workers. During colony growth, relatedness within the colony remains the same, but the costs of worker reproduction may change. The costs of worker reproduction are predicted to be greatest in incipient colonies. If the costs associated with worker reproduction outweigh the individual direct benefits to workers, policing mechanisms as found in larger colonies may be absent in incipient colonies. Results We investigated policing behaviour across colony growth in the ant Camponotus floridanus. In large colonies of this species, worker reproduction is policed by the destruction of worker-laid eggs. We found workers from incipient colonies do not exhibit policing behaviour, and instead tolerate all conspecific eggs. The change in policing behaviour is consistent with changes in egg surface hydrocarbons, which provide the informational basis for policing; eggs laid by queens from incipient colonies lack the characteristic hydrocarbons on the surface of eggs laid by queens from large colonies, making them chemically indistinguishable from worker-laid eggs. We also tested the response to fertility information in the context of queen tolerance. Workers from incipient colonies attacked foreign queens from large colonies; whereas workers from large colonies tolerated such queens. Workers from both incipient and large colonies attacked foreign queens from incipient colonies. Conclusions Our results provide novel insights into the regulation of worker reproduction in social insects at both the proximate and ultimate levels. At the proximate level, our results show that mechanisms of social regulation, such as the response to fertility

  20. Adaptive self-organization during growth of bacterial colonies

    NASA Astrophysics Data System (ADS)

    Ben-Jacob, Eshel; Shmueli, Haim; Shochet, Ofer; Tenenbaum, Adam

    1992-09-01

    We present a study of interfacial pattern formation during diffusion-limited growth of Bacillus subtilis. It is demonstrated that bacterial colonies can develop patterns similar to morphologies observed during diffusion-limited growth in non-living (azoic) systems such as solidification and electro-chemical deposition. The various growth morphologies, that is the global structure of the colony, are observed as we vary the growth conditions. These include fractal growth, dense-branching growth, compact growth, dendritic growth and chiral growth. The results demonstrate the action of a singular interplay between the micro-level (individual bacterium) and macro-level (the colony) in selecting the observed morphologies as is understood for non-living systems. Furthermore, the observed morphologies can be organized within a morphology diagram indicating the existence of a morphology selection principle similar to the one proposed for azoic systems. We propose a phase-field-like model (the phase being the bacterial concentration and the field being the nutrient concentration) to describe the growth. The bacteria-bacteria interaction is manifested as a phase dependent diffusion constant. Growth of a bacterial colony presents an inherent additional level of complexity compared to azoic systems, since the building blocks themselves are living systems. Thus, our studies also focus on the transition between morphologies. We have observed extended morphology transitions due to phenotypic changes of the bacteria, as well as bursts of new morphologies resulting from genotypic changes. In addition, we have observed extended and heritable transitions (mainly between dense branching growth and chiral growth) as well as phenotypic transitions that turn genotypic over time. We discuss the implications of our results in the context of the evolving picture of genome cybernetics. Diffusion limited growth of bacterial colonies combined with new understanding of pattern formation in azoic