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1

[A plastic model of a lost hospital: the San Lazzaro leper house].  

PubMed

The Museum of History of Medicine preserves a polychromatic plastic model drawned to a scale of one to one hundred. This model shows an hospital in Rome where, in the Middle Ages, it used to hospitalize lepers. The buildings were placed extra pomerium in account of sanitary reasons. They were composed of a church, that still does exist, and of a leper house, that was destroyed in 1938. The leper house became part of the Santo Spirito in Saxia hospital just in the XVIII century. PMID:12751483

Serarcangeli, Carla

2002-01-01

2

Colonial America.  

ERIC Educational Resources Information Center

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…

Web Feet K-8, 2001

2001-01-01

3

Colonial Williamsburg  

NSDL National Science Digital Library

In 1926, at the urging of the Revered Dr. D.A.R. Goodwin, John D. Rockefeller Jr. began a complex and elaborate restoration project in the quiet town of Williamsburg that sought to preserve a few of the more important Revolutionary War-era buildings around the town. The project became increasingly ambitious, and eventually grew to encompass around 85 percent of the town's area from the 18th century. Today, Colonial Williamsburg is the world's largest living history museum, and is noted for its ability to incorporate and interpret diverse perspectives on America's colonial period. Those persons unable to visit Colonial Williamsburg in person may want to first peruse the "Explore & Learn" section of the site, where they can learn about the different social and ethnic groups that inhabited the town (such as African-American slaves and colonial children), and see the various buildings within the community. The archaeology section of the site is particularly compelling, as visitors can learn about the many ongoing projects underway, and younger users can learn about the practice of archaeology through various games, quizzes, and puzzles. Additionally, users can read selected articles from the organization's popular history magazine, "Colonial Williamsburg," dating back to 1992. [KMG

4

Yeast Colony Embedding Method  

PubMed Central

Patterning of different cell types in embryos is a key mechanism in metazoan development. Communities of microorganisms, such as colonies and biofilms also display patterns of cell types. For example, in the yeast S. cerevisiae, sporulated cells and pseudohyphal cells are not uniformly distributed in colonies. The functional importance of patterning and the molecular mechanisms that underlie these patterns are still poorly understood. One challenge with respect to investigating patterns of cell types in fungal colonies is that unlike metazoan tissue, cells in colonies are relatively weakly attached to one another. In particular, fungal colonies do not contain the same extensive level of extracellular matrix found in most tissues . Here we report on a method for embedding and sectioning yeast colonies that reveals the interior patterns of cell types in these colonies. The method can be used to prepare thick sections (0.5 ?) useful for light microscopy and thin sections (0.1 ?) suitable for transmission electron microscopy. Asci and pseudohyphal cells can easily be distinguished from ovoid yeast cells by light microscopy , while the interior structure of these cells can be visualized by EM. The method is based on surrounding colonies with agar, infiltrating them with Spurr's medium, and then sectioning. Colonies with a diameter in the range of 1-2 mm are suitable for this protocol. In addition to visualizing the interior of colonies, the method allows visualization of the region of the colony that invades the underlying agar.

Piccirillo, Sarah; Honigberg, Saul M.

2011-01-01

5

My Moon Colony  

NSDL National Science Digital Library

Students are introduced to the futuristic concept of the moon as a place people can inhabit. They brainstorm what people would need to live on the moon and then design a fantastic Moon colony and decide how to power it. Student use the engineering design process, which includes researching various types of energy sources and evaluating which would be best for their moon colonies.

Integrated Teaching And Learning Program

6

HEMOPOIETIC SPLEEN COLONY STUDIES  

PubMed Central

The effects of phytohemagglutinin (PHA) were studied in irradiated mice to see if a definite myeloproliferative effect could be demonstrated in vivo. The data obtained suggested the following conclusions. PHA treatment of the bone marrow donor only, causes a consistent but slight reduction in transplantable spleen colony-forming unit (CFU) content of the bone marrow 24 hr after the last PHA injection, but no change was found in the proportion of the various colony types. PHA treatment of the irradiated recipient of normal bone marrow causes no change in the number of spleen colonies. However, 8-day colonies are only about half normal size, are much more likely to be of mixed cell types, contain many large undifferentiated blastoid cells, but fewer transplantable CFU. The spleen sinusoids are packed with hemopoietic cells. Spleen colonies developing in hosts receiving daily injections of PHA show, in addition to the usual spectrum of cell types, a high proportion of unusual blastoid cells resembling the PHA transformed peripheral lymphocytes seen in vitro. The function of these cells is not known, but they may represent augmented proliferation and/or transformation of stem cells. PHA administered after irradiation significantly increased the number of endogenous spleen colonies, and, at certain doses of irradiation, improved postirradiation survival. PHA administered before irradiation had no effect on the number of endogenous spleen colonies formed, or on postirradiation survival. On the basis of these and other data, possible modes of action of PHA are discussed.

Curry, J. L.; Trentin, J. J.

1967-01-01

7

Growth of Bacterial Colonies  

NASA Astrophysics Data System (ADS)

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.

Warren, Mya; Hwa, Terence

2013-03-01

8

Robotic space colonies  

NASA Technical Reports Server (NTRS)

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.

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

2001-01-01

9

Plymouth Colony, Massachusetts, USA  

NASA Technical Reports Server (NTRS)

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.

1990-01-01

10

Coloniality in the phylum Rotifera  

Microsoft Academic Search

Coloniality in the phylum Rotifera is defined and reviewed. Only two families of rotifers contain truly colonial forms: Flosculariidae and Conochilidae (order Gnesiotrocha, suborder Flosculariacea). Most species form intraspecific colonies ranging in size from a few to about 200 individuals, but species that produce enormous colonies (> 1000 individuals) are also known. All seven genera of the Flosculariidae contain species

Robert Lee Wallace

1987-01-01

11

Build a Colony!  

NSDL National Science Digital Library

In this activity, learners consider the requirements for human life beyond Earth's protection: air to breathe, plentiful food, shielding from ultraviolet light, power, etc. They then work in teams to design and construct a model of a space colony out of craft materials that would allow humans to survive the harsh environments of the Moon or Mars. Teams present their modules and colonies to one another and create a display for the library. This activity is part of Explore! To the Moon and Beyond! - developed specifically for use in libraries.

12

Colonial American Astronomy  

NASA Astrophysics Data System (ADS)

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.

Yeomans, Donald K.

2007-12-01

13

ISOPOLITICS, DEEP COLONIZING, SETTLER COLONIALISM  

Microsoft Academic Search

This essay contributes to interdisciplinary reflection on settler colonialism and decolonization by proposing an analysis of two characteristic traits of the ‘settler colonial situation’: isopolitics and deep colonizing. The first section outlines isopolitical relations as an alternative possibility to sustained colonial domination on the one hand, and internationally recognized independence within an international system of formally independent polities on the

Lorenzo Veracini

2011-01-01

14

Colonial House - PBS  

NSDL National Science Digital Library

Preview the newest installment in public television's hands-on history series, following Frontier House, Manor House, and 1900 House. Set in 1628, Colonial House will be broadcast in May. At the website, there are audio and video diaries in which the twenty-eight colonists from the UK and US give accounts of their experiences learning to live in 1628. Also provided is a map of the village and essays by the experts consulted for the show to insure historical authenticity. One such piece is _A Historian Awakens 1628_, by Emerson "Tad" Baker, a specialist on the early history of Maine, which is where Colonial House was filmed. There's also a Meet the Colonists gallery with photos and 21st and 17th century biographies of the settlers, lesson plans and activities for teachers, and a Resources section, with related Web sites and books.

15

Images of Colonialism  

NSDL National Science Digital Library

The history of colonialism is a compelling one, and it can be narrated through first-hand documents such as journals, drawings, or photographs. This particular digital collection from the Harvard College Library contains more than 700 images which offer insight into European perspectives on how popular perceptions of Asia and Africa were created and disseminated. The collection is primarily made up of late-19th and early-20th century trade cards and illustrated European newspapers. Visitors can use the collection to draw contrasts between colonial powers, such as the French, the British and the Dutch. First-time visitors will want to dive right into the collection, and the image viewer offered here allows visitors to zoom in for a closer look. While all of the items here are quite worthy, users shouldn't miss the cards created for the Liebig's Extract of Meat Company or the views of Bangkok.

16

Growing yeast into cylindrical colonies.  

PubMed

Microorganisms often form complex multicellular assemblies such as biofilms and colonies. Understanding the interplay between assembly expansion, metabolic yield, and nutrient diffusion within a freely growing colony remains a challenge. Most available data on microorganisms are from planktonic cultures, due to the lack of experimental tools to control the growth of multicellular assemblies. Here, we propose a method to constrain the growth of yeast colonies into simple geometric shapes such as cylinders. To this end, we designed a simple, versatile culture system to control the location of nutrient delivery below a growing colony. Under such culture conditions, yeast colonies grow vertically and only at the locations where nutrients are delivered. Colonies increase in height at a steady growth rate that is inversely proportional to the cylinder radius. We show that the vertical growth rate of cylindrical colonies is not defined by the single-cell division rate, but rather by the colony metabolic yield. This contrasts with cells in liquid culture, in which the single-cell division rate is the only parameter that defines the population growth rate. This method also provides a direct, simple method to estimate the metabolic yield of a colony. Our study further demonstrates the importance of the shape of colonies on setting their expansion. We anticipate that our approach will be a starting point for elaborate studies of the population dynamics, evolution, and ecology of microbial colonies in complex landscapes. PMID:24853750

Vulin, Clément; Di Meglio, Jean-Marc; Lindner, Ariel B; Daerr, Adrian; Murray, Andrew; Hersen, Pascal

2014-05-20

17

Colony image acquisition and genetic segmentation algorithm and colony analyses  

NASA Astrophysics Data System (ADS)

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.

Wang, W. X.

2012-01-01

18

The Colony of Jamestown  

NSDL National Science Digital Library

Learn who came over to Jamestown and why they came in the first place! First watch a video about why people came to the Americas: A video that explains why people came to the Americas in the first place Then once they got there, lets find out who was in Jamestown (click on Jamestown on the left hand side): Early American colonization Make sure you read up about the history of Jamestown: History of Jamestown and if thats confusion for you, here's another video: Video about the colony of Jamestown Once ...

Shaul, Ms.

2009-06-10

19

Colony image acquisition and segmentation  

NASA Astrophysics Data System (ADS)

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.

Wang, W. X.

2007-12-01

20

Post-Colonial Theory and Action Research  

ERIC Educational Resources Information Center

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…

Parsons, Jim B.; Harding, Kelly J.

2011-01-01

21

Colony collapse disorder in Europe.  

PubMed

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. PMID:23757238

Dainat, Benjamin; Vanengelsdorp, Dennis; Neumann, Peter

2012-02-01

22

New Topics in Colonies Theory  

Microsoft Academic Search

A colony, as introduced by Kelemen and Kelemenová in 1992, is meant to be a grammatical model of systems composed of as simple as possible agents which cooperate in such a way that a complex behaviour emerges at the level of the system. Technically, a colony is a symbol manipulating system consisting of as simple as possible components which behave

Carlos Martín-vide; Gheorghe P?un

1999-01-01

23

Genetic diversity affects colony survivorship in commercial honey bee colonies.  

PubMed

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. PMID:23728203

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

2013-08-01

24

Granulocytic colonies on macrophage-coated membranes  

Microsoft Academic Search

A macrophage cell coating covering a cellulose acetate disk was an effective microenvironment for the production of peroxidase-positive hematopoietic colonies. These developed after intraperitoneal injection of marrow cells with a linear cell relationship of dose to colonies formed. One colony formed for every 2000 nucleated marrow cells injected. Observation of colony formation daily showed a steady increase in number and

A. R. Turner; W. J. Pfrimmer; B. J. Torok-Storb; D. R. Boggs

1978-01-01

25

Zimbabwe Colonial and Post-Colonial Language Policy and Planning Practices  

ERIC Educational Resources Information Center

This monograph focuses on the development of colonial and post-colonial language policies and practices in Zimbabwe, attributing changes to evolving philosophies and politics in colonial and post-colonial Zimbabwe. In colonial Zimbabwe, we argue that the language policies had as one of their key objectives the development of a bilingual white…

Makoni, Sinfree B.; Dube, Busi; Mashiri, Pedzisai

2006-01-01

26

Catalog of California Seabird Colonies.  

National Technical Information Service (NTIS)

This catalog is a summary of the location, size, and species composition of seabird colonies along the California coast. It documents more than 260 nesting areas with a total estimated population of nearly 700,000 birds. Seventeen species of seabirds from...

A. L. Sowls A. R. DeGange J. W. Nelson G. S. Lester

1980-01-01

27

The Roanoke Island Freedmen's Colony  

NSDL National Science Digital Library

During the Civil War, Roanoke Island, located between the coast of North Carolina and the Outer Banks, became a refuge for escaped slaves, called contrabands or freedmen. This site, created by University of Virginia professor Patricia C. Click presents an account of the history and selected documents and maps of the Roanoke Island Freedmens Colony, as the community was known. Documents include letters from Superintendent of the Colony, Horace James, a minister and abolitionist from Massachusetts, and letters from Freedmen themselves. The documents have been transcribed and are in .pdf format, so users should not expect to see scanned versions of 19th century originals. The projects section includes seven projects for high school and college students, using historical materials at the site, and from other related Web sites. Professor Click has written a book, Time Full of Trial: The Roanoke Island FreedmenâÂÂs Colony, 1862-1867, and the Preview section contains the table of contents and Chapter One. Links in the site refer to this book for more information; in the Maps section users are referred to its online ordering instructions for more information on the layout of the colony.

Click, Patricia C.

2001-01-01

28

New colony formation in the \\  

Microsoft Academic Search

If the adaptive significance of sexual reproduction derives from genetic recombination, then sexual organisms that severely inbreed minimize the benefits of sexuality without fully escaping its costs. Local populations of the eusocial naked mole-rat are extremely genetically uniform, and colonies have the highest inbreeding coefficient known for wild mammals. Because non- breeding workers cooperate to rear the queen's offspring, researchers

Deborah Ciszek

2000-01-01

29

Meteorology in a Space Colony  

Microsoft Academic Search

It is pointed out that the weather in a space colony proposed by O'Neill is considerably different from that on the earth. Atmospheric circulation is produced by a temperature difference between the land area and the window area, and it is restricted within the thermal boundary layer. On the `window shore', strong `window-wind' blows in a day time.

Takuya Matsuda

1983-01-01

30

Queen promiscuity lowers disease within honeybee colonies  

PubMed Central

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

Seeley, Thomas D; Tarpy, David R

2006-01-01

31

Ant Colony System for JSP  

Microsoft Academic Search

\\u000a This paper discusses the application of ACS metaheuristics (based on behaviour of real ants: stigmergy and synergetic effect\\u000a among ants) for Job-Shop Scheduling problem (JSP). This algorithm is improved by introducing the concept of critical events,\\u000a in which two new techniques will be applied. Thus, a more flexible heuristic technique is obtained, which improves the performance\\u000a of ant colony system

Urszula Boryczka

2004-01-01

32

Allorecognition between compound ascidian colonies.  

PubMed

The compound ascidian Botryllus schlosseri reproduces asexually, and forms colonies to adhere to matrices such as rocks. This species has developed a mechanism to distinguish between self stem cells and invasive parasitizing nonself cells from other individuals of the same species, probably as a defense against parasitism. It is highly likely that such adult colony histocompatibility is controlled differently from its gametic allorecognition during fertilization. Allorecognition in adults is controlled by a single fusion/histocompatibility (FuHC) locus. In 2005, a candidate gene responsible for the phenotype associated with this genetic locus, named cFuHC, was reported; however, this proposal was subsequently refuted, and the actual determinant may exist elsewhere within the FuHC locus. Given that its is unlikely that a single gene could produce the diversity of FuHC alleles needed to determine individual identity and to distinguish self from nonself colonies, it is possible that the FuHC locus consists of a cluster of multiple determinants aligned in tandem. PMID:24004073

Harada, Yoshito

2013-09-01

33

Deadly competition between sibling bacterial colonies  

NASA Astrophysics Data System (ADS)

As a result of stress due to nutrient limitation or antibiotics, competing individual bacteria within a single colony may lyse sibling cells to release nutrients (cannibalism) or DNA (fratricide). However, we have recently shown that competition is not limited to individuals, but can occur at the colony level [A. Be'er et al., PNAS 106, 428 (2009); A. Be'er et al., PNAS 107, 6258 (2010).] In response to the presence of an encroaching sibling colony, Paenibacillus dendritiformis bacteria secrete a lethal protein, lysing cells at the interface between the colonies. Analysis of the proteins secreted by these competing sibling colonies, combined with a mathematical model, shows how colonies maintain their growth by self-regulating the secretion of two proteins: subtilisin (a well-known growth promoter), and Slf (a previously unknown protein, which is lethal). The results also explain why a single colony is not inhibited by its own secretions.

Be'Er, Avraham

2011-03-01

34

Granulocytic colonies on macrophage-coated membranes.  

PubMed

A macrophage cell coating covering a cellulose acetate disk was an effective microenvironment for the production of peroxidase-positive hematopoietic colonies. These developed after intraperitoneal injection of marrow cells with a linear cell relationship of dose to colonies formed. One colony formed for every 2,000 nucleated marrow cells injected. Observation of colony formation daily showed a steady increase in number and size until seven days after cell inoculation. X-irradiation (400 rads) eliminated intrinsic colony formation in BALB/c mice. Irradiation of the donor of the ip marrow cells resulted in a d0 of 95 rads. Treatment of the marrow donor with cytosine arabinoside had a suppressive effect on colony formation as did treatment of the host animal after receipt of the ip marrow. These results indicate that the precursor of the granulocytic colonies seen in the macrophage layers are more similar to committed granulocytic precursors than to the pluripotential stem cell. PMID:354375

Turner, A R; Pfrimmer, W J; Torok-Storb, B J; Boggs, D R

1978-01-01

35

Colonial Landscape and Rock Origin  

NSDL National Science Digital Library

This activity is designed to help students develop appreciation and ownership for the natural world around them with the hope of increasing their interest in exploring and questioning the processes that created land forms. Some familiarity with stone walls and with colonial New England is helpful; the students should learn to understand how human endeavors affect the landscape. After taking a nature walk (hopefully in an area where there are stone walls), they will participate in an activity in which they "build" a model wall using stones buried in a plastic tray.

36

Conceptual design of a lunar colony  

NASA Technical Reports Server (NTRS)

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.

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

1972-01-01

37

The MacDowell Colony Exhibition  

NSDL National Science Digital Library

Artist colonies have always fascinated the American public, and whether they have been informally organized or not, they seem to provide great opportunities for a variety of collaborations. One of the oldest of these colonies is the MacDowell Colony in Peterborough, New Hampshire. The colony was started in 1907 by the composer Edward MacDowell and his wife Marian, and over the past century it has been host to the likes of Willa Cather, Leonard Bernstein, Thorntown Wilder, and James Baldwin. This site was created in conjunction with an in situ exhibit at the Thomas Jefferson Building at the Library of Congress, and visitors to the site will be able to learn about the history of the colony through first-hand accounts, video clips featuring the curators of the exhibit, and objects that have been part of the colony's history. Some of these digitized objects include photographs, manuscripts, and musical scores.

38

The Human Hematopoietic Colony-Stimulating Factors  

Microsoft Academic Search

The complementary DNAs and genes encoding the four major human myeloid growth factors--granulocyte colony-stimulating factor, macrophage colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, and interleukin-3--have all been molecularly cloned. These DNA clones have proved valuable for studying the molecular biology of these important regulatory molecules as well as for the large-scale production of the recombinant growth factor proteins. These advances have led

Steven C. Clark; Robert Kamen

1987-01-01

39

Science, Technology and Institutional Co-operation in Africa: From Pre-Colonial to Colonial Science  

Microsoft Academic Search

This paper covers two phases of the history of science, technology and institutional co-operation in Africa - pre-colonial and colonial. It is structured into three sections. Section one looks at pre-colonial science and technology (S&T) and points out that most discussions on the socio- economic analysis of S&T in Africa often neglect the pre-colonial phase, even though indigenous knowledge is

Frank K. Teng-Zeng

2006-01-01

40

Displaying colonial artifacts in Paris at the Musée Permanent des Colonies to Musée du Quai Branly  

Microsoft Academic Search

The vast cultural artifacts plundered from Africa, Asia, the Pacific region, and the Americas – regions in which France once had colonies, have been distributed among various museums in Paris. For the past seven decades, much of these artifacts from the colonies were at various museums including the Musée Permanent des Colonies (whose name has changed several times) until President

Fassil Demissie

2009-01-01

41

Swarming dynamics in bacterial colonies  

NASA Astrophysics Data System (ADS)

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.

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

2009-08-01

42

Temporal changes in colony cuticular hydrocarbon patterns of Solenopsis invicta  

Microsoft Academic Search

Heritable cuticular hydrocarbon patterns ofSolenopsis invicta workers are consistent within colonies for a given sampling time but vary sufficiently from colony to colony to distinguish the colonies from each other. In addition, cuticular hydrocarbon patterns change within colonies over time. Nestmate recognition cues found on the individual's cuticle, can be from heritable or environmental sources, and are a subset of

Robert K. vander Meer; David Saliwanchik; Barry Lavine

1989-01-01

43

Holotransformations of bacterial colonies and genome cybernetics  

Microsoft Academic Search

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

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

1994-01-01

44

Deadly competition between sibling bacterial colonies  

PubMed Central

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.

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

2009-01-01

45

Governmentality, congestion and calculation in colonial Delhi  

Microsoft Academic Search

This paper seeks to explore a different way of examining the ‘difference’ of European and colonial governments, showing how the Indian colonial state privileged investments in political, rather than civil, society. The former targeted the population and sought effects through policies that could be co-ordinated from a distance, at low cost. The latter targeted the social realm and necessarily involved

Stephen Legg

2006-01-01

46

Colony Collapse Disorder: A Descriptive Study  

Microsoft Academic Search

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

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

2009-01-01

47

Colony Collapse Disorder: A Descriptive Study  

Microsoft Academic Search

BackgroundOver 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

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

2009-01-01

48

Education in Colonial Africa: The German Experience  

ERIC Educational Resources Information Center

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…

vanderPloeg, Arie J.

1977-01-01

49

Post-Colonial Recovering and Healing.  

ERIC Educational Resources Information Center

Notions of white supremacy, racism, sexism, and patriarchy constitute the power relationships and hierarchical structures of colonialism. Power is accessed when certain cultural forms are made to prevail over others, thus producing racialized and marginalized identities. The will to control what is different is the main tenet of colonialism.…

Weenie, Angelina

50

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

Microsoft Academic Search

In this work we introduce the confluent and various sizes image analysis method (COVASIAM), an auto- mated 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

G. CORKIDI; R. DIAZ-URIBE; J. L. FOLCH-MALLOL; J. NIETO-SOTELO

51

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

PubMed Central

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.

Manderson, L

1999-01-01

52

Colony image acquisition system and segmentation algorithms  

NASA Astrophysics Data System (ADS)

This paper presents a novel colony analysis system including an adjustable image acquisition subsystem and a wavelet-watershed-based image segmentation algorithm. An illumination box was constructed--both front lightning and back lightning illuminations can be chosen by users based on the properties of Petri dishes. In the illumination box, the lightning is uniform, which makes image processing easy. A digital camera at the top of the box is connected to a PC computer; all the camera functions are controlled by the developed computer software in this study. As usual, in the image processing part, the hardest task is image segmentation which is carried out by the four different algorithms: 1. recursive image segmentation on gray similarity; 2. canny edge detection-based segmentation; 3. the combination of 1 and 2, and 4. colony delineation on wavelet and watershed. The first three algorithms can obtain good results for ordinary colony images, and for the images including a lot of small (tiny) colonies and dark colonies and overlapping (or touching) colonies, the algorithm 4 can obtain better results than the others. The algorithms are tested by using a large number of different colony images, and the testing results are satisfactory.

Wang, Weixing

2011-12-01

53

Swarming dynamics in bacterial colonies  

NASA Astrophysics Data System (ADS)

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.

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

2009-11-01

54

21 CFR 866.2180 - Manual colony counter.  

Code of Federal Regulations, 2010 CFR

...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2180 Manual colony counter. (a) Identification. A manual colony...

2009-04-01

55

Ant Colonies Shed Light on Metabolism  

NSDL National Science Digital Library

Press Release. Ants are usually regarded as the unwanted guests at a picnic. But a recent study of California seed harvester ants (Pogonomyrmex californicus) examining their metabolic rate in relation to colony size may lead to a better appreciation for the social, six-legged insects, whose colonies researchers say provide a theoretical framework for understanding cellular networks. Mr. Waters presented his paper, Scaling of Metabolism, Growth and Network Organization in Colonies of the Seed Harvester Ant, Pogonomyrmex californicus, at the American Physiological SocietyÃÂs Intersociety Meeting Global Science: Comparative Physiology in a Changing World. The program is located at http://the-aps.org/meetings/aps/comparative/preprogram.htm.

APS Communications Office (American Physiological Society Communications Office)

2010-08-26

56

History: The Colonial Williamsburg Official History Site  

NSDL National Science Digital Library

Colonial Williamsburg has been a popular destination for American history buffs for eight decades, and they continue to impress with their fine website dedicated to providing biographies, essays, and articles on "the everyday life of extraordinary Americans." Visitors can read biographies of people who inhabited colonial-era Williamsburg, listen to their fife and drums corps, and tour the town. One area that is definitely worth a look is the "Gardens" section of the site. Here visitors can learn about the landscape restoration work on the site, the history of the gardens, and read the gardener's blog. Further along, the "Clothing" area includes narrative descriptions of men's clothing, women's clothing, and African American clothing during colonial times. Also, visitors can dress a colonial person from head to toe in the interactive adventure, "Dressing the Part". The site is rounded out by a "Conferences, Forums, and Workshops" area that includes information about their scholarly activities and upcoming forums.

57

Growth and form of melanoma cell colonies  

NASA Astrophysics Data System (ADS)

We study the statistical properties of melanoma cell colonies grown in vitro by analyzing the results of crystal violet assays at different concentrations of initial plated cells and for different growth times. The distribution of colony sizes is described well by a continuous time branching process. To characterize the shape fluctuations of the colonies, we compute the distribution of eccentricities. The experimental results are compared with numerical results for models of random division of elastic cells, showing that experimental results are best reproduced by restricting cell division to the outer rim of the colony. Our results serve to illustrate the wealth of information that can be extracted by a standard experimental method such as the crystal violet assay.

Baraldi, Massimiliano Maria; Alemi, Alexander A.; Sethna, James P.; Caracciolo, Sergio; La Porta, Caterina A. M.; Zapperi, Stefano

2013-02-01

58

Identification of a Colonial Chordate Histocompatibility Gene  

PubMed Central

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.

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

59

Considerations for Lunar Colony Communications Systems.  

National Technical Information Service (NTIS)

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 suppo...

R. P. Dowling

1992-01-01

60

Morphology of Mature Mycobacterium ulcerans Colonies  

NSDL National Science Digital Library

Macroscopic examination reveals the presence of large and small Mycobacterium ulcerans colonies after 3 and 5 months of growth at 30ðC on Middlebrook 7H10 agar supplemented with 10% oleic acid, albumin, dextrose, and catalase (OADC).

Shelley Haydel (Arizona State University;); Caitlin Otto (Arizona State University;)

2011-04-28

61

Biomimicry: Further Insights from Ant Colonies?  

Microsoft Academic Search

Biomimicry means learning from nature. Well known examples include physical structures such as the Velcro fastener. But natural\\u000a selection has also “engineered” mechanisms by which the components of adaptive biological systems are organized. For example,\\u000a natural selection has caused the foragers in an ant colony to cooperate and communicate in order to increase the total foraging\\u000a success of the colony.

Francis L. W. Ratnieks

2007-01-01

62

Pathogen Webs in Collapsing Honey Bee Colonies  

PubMed Central

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.

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

2012-01-01

63

Grazer-induced colony formation in Scenedesmus: are there costs to being colonial?  

Microsoft Academic Search

Grazer-induced colony formation in the common green alga Scenedesmus acutus may be interpreted as an anti-grazer defense. Costs are to be expected because otherwise the protected colonial morph would be the norm. Analysis of growth rates, light harvesting in terms of photosystem II (PSII) efficiency using Xe-PAM fluorescence measurements and sedimentation rates were compared among unicellular and induced colonial populations.

M. Lürling; Ellen Van Donk

2000-01-01

64

The mode transition of the bacterial colony  

NASA Astrophysics Data System (ADS)

The colony patterns of Bacillus circulans on agar medium were experimentally investigated to study about the growth mode transition. From the optical microscopic observation, the bacteria distribute inside the medium, that is, the colony grows three-dimensionally (3D) in the soft agar condition (C A<0.9 wt%) . On the other hand, the bacteria distribute on the surface, that is, the colony grows two-dimensionally (2D) in the hard agar condition (C A?0.9 wt%) . It indicates that the mode transition occurs by changing the hardness of the medium. The mode transition is confirmed by the discontinuous change in the pattern diagram and in the colony growth rate, which is defined as the expanding speed of the colony. Under the softer agar condition in the range of the 2D mode (0.9?C A?1.2 wt%) , the induction time exists. Before the induction time, the colony grows in 3D mode. The length of the induction time decreases with increasing the bacterial number density. In addition, bacterial aggregation plays a key role on 2D growth. These results suggest that the increasing bacterial number density causes bacterial aggregation resulting in the mode transition.

Eiha, Noriko; Komoto, Atsushi; Maenosono, Shinya; Yuichiro Wakano, Joe; Yamamoto, Kenji; Yamaguchi, Yukio

2002-10-01

65

Breeding Production and Success at Kittiwake Colonies in Shetland, 1986,  

National Technical Information Service (NTIS)

Kittiwake chick production was measured at 7 study plots in 3 colonies on the Mainland of Shetland. While the number of young fledged per pair at one colony was comparable to that reported from other British colonies, production at the other 2 colonies wa...

M. Heubeck

1986-01-01

66

How Did Colonialism Dispossess? Comments from an Edge of Empire  

Microsoft Academic Search

The emphasis on culture in studies of colonialism tends to obscure other forms of colonial power while making it impossible to contextualize the cultural argument and assess its salience. Rather than focusing on texts, systems of signification, and procedures of knowledge generation, as the colonial discourse literature is wont to do, a fuller understanding of colonial powers is achieved by

Cole Harris

2004-01-01

67

Unrelated queens coexist in colonies of the termite Macrotermes michaelseni.  

PubMed

Relatedness increases the likelihood of cooperation within colonies of social insects. Polygyny, the coexistence of numerous reproductive females (queens) in a colony, is common in mature colonies of the termite Macrotermes michaelseni. In this species, polygyny results from pleometrosis and from several female alates that jointly found a new colony. To explain this phenomenon, it was suggested that only related females cooperate and survive during maturation of colonies. Using multilocus fingerprints as well as microsatellites, we showed that nestmate queens in mature colonies are unrelated. Furthermore, we found that all nestmate queens contributed to the production of steriles. Even in mature colonies, several matrilines of steriles coexist within a colony. Although genetic diversity within colonies may increase the likelihood of conflicts, high genetic diversity may be important for foraging, colony growth, and resistance to disease and parasites. PMID:15813790

Hacker, M; Kaib, M; Bagine, R K N; Epplen, J T; Brandl, R

2005-04-01

68

Material Culture and Colonial Networks in the Cape Colony and the Indian Ocean  

Microsoft Academic Search

This review article considers four recent books published on the social and cultural history of the Cape Colony and Batavia, spanning a chronological period from the mid-seventeenth through to the mid-nineteenth centuries. The books address a wide range of topics and themes, but they all share an interest, to a greater or lesser extent, in the material culture of colonial

Wayne Dooling

2010-01-01

69

Leprosy  

MedlinePLUS

... exist. Isolating people with this disease in "leper colonies" is not needed. Drug-resistant Mycobacterium leprae and ... Lepromin skin test can be used to tell the two different forms of leprosy apart, but it is not used to ...

70

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

PubMed Central

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.

Liu, Liqiang; Dai, Yuntao

2014-01-01

71

Genetic diversity within honeybee colonies prevents severe infections and promotes colony growth.  

PubMed Central

Multiple mating by social insect queens increases the genetic diversity among colony members, thereby reducing intracolony relatedness and lowering the potential inclusive fitness gains of altruistic workers. Increased genetic diversity may be adaptive, however, by reducing the prevalence of disease within a nest. Honeybees, whose queens have the highest levels of multiple mating among social insects, were investigated to determine whether genetic variation helps to prevent chronic infections. I instrumentally inseminated honeybee queens with semen that was either genetically similar (from one male) or genetically diverse (from multiple males), and then inoculated their colonies with spores of Ascosphaera apis, a fungal pathogen that kills developing brood. I show that genetically diverse colonies had a lower variance in disease prevalence than genetically similar colonies, which suggests that genetic diversity may benefit colonies by preventing severe infections.

Tarpy, David R

2003-01-01

72

Colony Collapse Disorder: A Descriptive Study  

PubMed Central

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.

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

73

Quantitative analysis of colony morphology in yeast  

PubMed Central

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.

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

2014-01-01

74

Sociometry and sociogenesis of colonies of the harvester ant, Pogonomyrmex badius : worker characteristics in relation to colony size and season  

Microsoft Academic Search

Summary: As colonies of all monogyne ants grow from a single, colony-founding queen to a mature colony with many workers, they develop the species-typical characteristics of the mature colony. This ontogeny, and these species-typical characteristics and their seasonal changes were studied in the Florida harvester ant by excavating 31 colonies of the full range of sizes, on 4 dates representing

W. R. Tschinkel

1998-01-01

75

Energetic inequivalence in eusocial insect colonies  

PubMed Central

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.

DeLong, John P.

2011-01-01

76

Evangelists of Empire? Missionaries in Colonial History  

NSDL National Science Digital Library

The role of missionaries in the process of colonization has intrigued historians and others for decades, and this compilation of scholarly works on this subject is quite a find. This set of papers was published by the eScholarship Research Centre at The University of Melbourne in July 2008, and it contains fifteen works that look at "current concepts of gender, race and colonial governance." Drawing on a range of methodological and theoretical approaches, the works are divided into thematic sections such as "Consolidating the Missionary Project" and "A Global Mission". Within these sections, visitors will find papers that include "Imperial Critics: Moravian Missionaries in the British Colonial World" and "Missions, Colonialism and the Politics of Agency". For persons with an interest in these types of historical explorations, this site will prove quite indispensable.

77

The effects of colony-level selection on the social organization of honey bee (Apis mellifera L.) colonies: colony-level components of pollen hoarding  

Microsoft Academic Search

Two-way selection for quantities of stored pollen resulted in the production of high and low pollen hoarding strains of honey bees (Apis mellifera L.). Strains differed in areas of stored pollen after a single generation of selection and, by the third generation, the high strain colonies stored an average 6 times more pollen than low strain colonies. Colony-level organizational components

Robert E. Page; M. Kim Fondrk

1995-01-01

78

Fluorescent in situ sequencing on polymerase colonies  

Microsoft Academic Search

Integration of DNA isolation, amplification, and sequencing can be achieved by the use of polymerase colonies (polonies) and cycles of fluorescent dNTP incorporation. In this paper, we present four advances that bring us closer to sequencing genomes cost-effectively using the polony technology. First, a polymerase trapping technique enables efficient nucleotide extension by DNA polymerase in a polyacrylamide matrix and eliminates

Robi D. Mitra; Jay Shendure; Jerzy Olejnik; George M Church

2003-01-01

79

Ant colony optimization for disaster relief operations  

Microsoft Academic Search

This paper presents a meta-heuristic of ant colony optimization (ACO) for solving the logistics problem arising in disaster relief activities. The logistics planning involves dispatching commodities to distribution centers in the affected areas and evacuating the wounded people to medical centers. The proposed method decomposes the original emergency logistics problem into two phases of decision making, i.e., the vehicle route

Wei Yi; Arun Kumar

2007-01-01

80

Teaching the History of Colonial Peru.  

ERIC Educational Resources Information Center

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…

Campbell, Leon G.

1981-01-01

81

Land Rover and colonial-style adventure  

Microsoft Academic Search

This article examines the infamous Land Rover ‘Himba’ advertisement (2000) that shocked South Africans because of its racism and sexism. The South African Advertising Standards Authority ruled that the advertisement constituted a violation of human dignity that perpetuated gender and cultural inequality. This article takes the position that the Himba advertisement builds on the colonial notions of adventure, exploration and

Jeanne Van Eeden

2006-01-01

82

Policing native pleasures: a colonial history.  

PubMed

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. PMID:23240839

Jabbar, Naheem

2012-12-01

83

Ant Colony Optimisation for Machine Layout Problems  

Microsoft Academic Search

Flexible machine layout problems describe the dynamic arrangement of machines to optimise the trade-off between material handling and rearrangement costs under changing and uncertain production environments. A previous study used integer-programming techniques to solve heuristically reduced versions of the problem. As an alternative, this paper introduces an ant colony optimisation (ACO) algorithm to generate good solutions. Experimental results are presented,

Paul Corry; Erhan Kozan

2004-01-01

84

Teamwork in Self-Organized Robot Colonies  

Microsoft Academic Search

Swarm robotics draws inspiration from decentral- ized self-organizing biological systems in general and from the collective behavior of social insects in particular. In social insect colonies, many tasks are performed by higher order group or team entities, whose task-solving capacities transcend those of the individual participants. In this paper, we investigate the emergence of such higher order entities. We report

Shervin Nouyan; Roderich Gross; Michael Bonani; Francesco Mondada; Marco Dorigo

2009-01-01

85

OVERALL DESIGN OF MOON AND MARS COLONIES  

Microsoft Academic Search

This paper presents the thoughts of the MoonMars Workshop regarding the overall design of Moon and Mars Colonies. This workshop, held in conjunction with the International Astronautical Congress 2003 and the 3rd European Mars Conference (EMC3) in Bremen, was born from a Space Generation Summit* (SGC) with the overall goal of accelerating our pace in space.

Vega Plc; Jeffrey Hendrikse; Tiago S. Hormigo; Alexander Soucek; Gillian Whelan

86

The space colony proposal: Limited thinking applied  

Microsoft Academic Search

Responds to the comments of C. J. Divine (1979) on a previous article (P. C. Stern, 1978) on the limits-to-growth controversy. The notion of a space colony is challenged in regard to being able to predict the effects of proposed changes by extrapolation from past experience, the resulting type of freedom, and the impact on the state of the impoverished.

Paul C. Stern

1979-01-01

87

Monitoring of Puffin numbers at Scottish colonies  

Microsoft Academic Search

Annual counting of occupied burrows in fixed areas of seven Puffin colonies in Scotland showed that the populations there were either stable or increasing. A drop of even 30% in the number of burrows between one year and the next could not be attributed to a disaster as the numbers increased greatly the next year.

M. P. Harris; S. Murray

1981-01-01

88

Agar Concentration in Counting Clostridium Colonies.  

National Technical Information Service (NTIS)

Decreasing the agar concentration of a counting medium from the usual 1.5% resulted in larger colonies with less interference from gas in Clostridium botulinum 115B and C. sporogenes PA 3679. Optimal agar concentration was 0.65% for C. botulinum with 24-h...

C. Eller L. Rogers E. S. Wynne

1966-01-01

89

Colonial Continuities and Educational Inequalities in Indonesia.  

ERIC Educational Resources Information Center

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…

Carpenter, Harold F., Jr.

90

Buckling instability in ordered bacterial colonies.  

PubMed

Bacterial colonies often exhibit complex spatio-temporal organization. This collective behavior is affected by a multitude of factors ranging from the properties of individual cells (shape, motility, membrane structure) to chemotaxis and other means of cell-cell communication. One of the important but often overlooked mechanisms of spatio-temporal organization is direct mechanical contact among cells in dense colonies such as biofilms. While in natural habitats all these different mechanisms and factors act in concert, one can use laboratory cell cultures to study certain mechanisms in isolation. Recent work demonstrated that growth and ensuing expansion flow of rod-like bacteria Escherichia coli in confined environments leads to orientation of cells along the flow direction and thus to ordering of cells. However, the cell orientational ordering remained imperfect. In this paper we study one mechanism responsible for the persistence of disorder in growing cell populations. We demonstrate experimentally that a growing colony of nematically ordered cells is prone to the buckling instability. Our theoretical analysis and discrete-element simulations suggest that the nature of this instability is related to the anisotropy of the stress tensor in the ordered cell colony. PMID:21358041

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

2011-04-01

91

The Adaptation Concept in British Colonial Education.  

ERIC Educational Resources Information Center

The history of British colonial educational policies, particularly the adaptation concept in Black Africa, is discussed. "Adaptation" refers to an educational scheme, supposedly adapted to the needs of Black people, completely oriented toward family and community life, and based on recommendations by the 1920-21 and 1924 Phelps-Stokes Commission…

Bude, Udo

1983-01-01

92

Ant colony optimization for continuous domains  

Microsoft Academic Search

In this paper we present an extension of Ant Colony Optimization (ACO) to continuous domains. We show how ACO, which was initially developed to be a metaheuristic for combinatorial optimization, can be adapted to continuous opti- mization without any major conceptual change to its structure. We present the general idea, implementation, and results obtained. We compare the results with those

Krzysztof Socha; Marco Dorigo

2008-01-01

93

Buckling instability in ordered bacterial colonies  

PubMed Central

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

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

2013-01-01

94

Ant colony system with communication strategies  

Microsoft Academic Search

In this paper an ant colony system (ACS) with communication strategies is devel- oped. The artificial ants are partitioned into several groups. Seven communication methods for updating the pheromone level between groups in ACS are proposed and work on the traveling salesman problem using our system is presented. Experimental results based on three well-known traveling salesman data sets demonstrate the

Shu-chuan Chu; John F. Roddick; Jeng-shyang Pan

2004-01-01

95

Colony Fusion in a Parthenogenetic Ant, Pristomyrmex punctatus  

PubMed Central

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.

Satow, Show; Satoh, Toshiyuki; Hirota, Tadao

2013-01-01

96

Clonal origin of human erythro-eosinophilic colonies in culture.  

PubMed

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. PMID:7059681

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

1982-04-01

97

Nest-size and colony characteristics of wading birds in selected Atlantic Coast colonies  

USGS Publications Warehouse

Nests of 5 species of wading birds were identified and marked during the breeding season at 6 locations from Massachusetts to North Carolina. 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 analyses were used to describe and compare sites and species.....We found that 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 seemed to determine whether nest-sites were stratified, segregated or randomly distributed.

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

1980-01-01

98

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

USGS Publications Warehouse

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.

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

1980-01-01

99

Colony Collapse Disorder Progress Report. CCD Steering Committee June 2009.  

National Technical Information Service (NTIS)

In response to the unexplained losses of U.S. honey bee colonies now known as colony collapse disorder (CCD), USDA's Agricultural Research Service (ARS) and Cooperative State Research, Education, and Extension Service (CSREES) led a collaborative effort t...

B. McPheron D. Holy K. Hackett M. Purcell-Miramontes R. Meyer R. Rose S. Ramaswamy T. Steeger

2009-01-01

100

A Quantitative Model of Honey Bee Colony Population Dynamics  

PubMed Central

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.

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

2011-01-01

101

A quantitative model of honey bee colony population dynamics.  

PubMed

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

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

2011-01-01

102

Growth pattern of the surface of fungus Aspergillus colony  

NASA Astrophysics Data System (ADS)

Aspergillus oryzae colonies were grown under various glucose concentrations, temperatures, and agar concentrations, and the effects on the pattern were investigated. Patterns of colony were found to vary from uniform to diffusion-limited aggregation type.

Matsuura, Shu; Miyazima, Sasuke

1992-05-01

103

Colony age, neighborhood density and reproductive potential in harvester ants  

Microsoft Academic Search

At about age 5?years, colonies of the harvester ant, Pogonomyrmex barbatus, begin to produce winged, sexual forms (alates) that mate in large annual aggregations. We examined how colony age and neighborhood\\u000a density affect the numbers, body mass, and body fat of alates produced by 172 colonies ranging in age from 4 to 17?years.\\u000a Over one-third (36%) of all colonies produced

Diane Wagner; Deborah M. Gordon

1999-01-01

104

Constructing Indigenous Childhoods: Colonialism, Vocational Education and the Working Child.  

ERIC Educational Resources Information Center

Examines a Calcutta street child's experiences with vocational education within a broader historical framework of colonial and post-colonial discourses on formal education and the poor. Provides an ethnographic narrative of the child's experiences, exploring how colonialism, by establishing a modern education system and transforming children's…

Balagopalan, Sarada

2002-01-01

105

Formation of complex bacterial colonies via self-generated vortices  

Microsoft Academic Search

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

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

1996-01-01

106

Chemotactic-based adaptive self-organization during colonial development  

Microsoft Academic Search

Bacterial colonies have developed sophisticated modes of cooperative behavior which enable them to respond to adverse growth conditions. It has been shown that such behavior can be manifested in the development of complex colonial patterns. Certain bacterial species exhibit formation of branching patterns during colony development. Here we present a generic model to describe such patterning of swimming (tumbling) bacteria

Inon Cohen; Andras Czirók; Eshel Ben-Jacob

1996-01-01

107

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

ERIC Educational Resources Information Center

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,…

Gruenbaum, Thelma

108

Colony Growth of Human Leukemic Peripheral Blood Cells In Vitro  

Microsoft Academic Search

The colony-forming potential of pen- acute stem cell leukemia gave rise to no pheral white blood cells from patients colonies or only small numbers. Colonies with acute leukemia on normal human formed from WBC of patients with AGL peripheral WBC feeder layers has been appear to go through a process of mor- studied. White blood cells from 12 of 20

WILLIAM A. ROBINSON; JOHN E. KURNICK; L. PIKE

1971-01-01

109

Iridovirus and Microsporidian Linked to Honey Bee Colony Decline  

Microsoft Academic Search

BackgroundIn 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

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

2010-01-01

110

An Exploratory Study of Online Information Regarding Colony Collapse Disorder  

Microsoft Academic Search

The cause or causes of Colony Collapse Disorder (CCD) are uncertain. CCD defines specific characteristics of the nationwide deaths of honey bee colonies in the last decade. Adult bees often disappear from the hive and die, leaving the colony weak and vulnerable to disease. Environmental scientists and agriculturalists have developed many different theories about CCD and its origins. The different

Meredith K. Boehm

2012-01-01

111

Parallel Ant Colonies for the quadratic assignment problem  

Microsoft Academic Search

Ant Colonies optimization take inspiration from the behavior of real ant colonies to solve optimization problems. This paper presents a parallel model for ant colonies to solve the quadratic assignment problem (QAP). The cooperation between simulated ants is provided by a pheromone matrix that plays the role of a global memory. The exploration of the search space is guided by

El-ghazali Talbi; Olivier H. Roux; Cyril Fonlupt; Denis Robillard

2001-01-01

112

A Post-Colonial Reading of Affirmative Action in Fiji.  

ERIC Educational Resources Information Center

Presents a post-colonial reading of affirmative action (AA) policies in Fiji, arguing that AA was a deliberate response by various predominantly indigenous Fijian post-colonial governments to counter the effects of a discriminatory colonial history that produced significant educational and employment inequality. Analyzes the mixed outcomes of AA…

Puamau, Priscilla Qolisaya

2001-01-01

113

Deformed wing virus implicated in overwintering honeybee colony losses.  

PubMed

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

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

114

The colonial career of James Patrick Murray.  

PubMed

This paper is a biographical sketch of Dr. Murray during the years 1860 to 1873 when he lived in Victoria, New Zealand and the Pacific Islands. It records details of his career from his residency at the Melbourne Hospital followed by his exemplary conduct in the Howitt expedition to recover the remains of Burke and Wills. It traces his progress of degradation unhampered by constituted authority and concludes with his magnum opus--the greatest massacre of South Sea Islanders in the annals of the South Sea slave trade. He departed from the colonies still registered to practise medicine and without penalty or probation. This paper concludes with a brief summary of his personal qualities and asserts that it was these qualities, together perhaps with the discordance between the colonies, which allowed this knave to escape the penalty which he appeared amply to deserve. PMID:380544

Elmslie, R

1979-02-01

115

Motif Finding Using Ant Colony Optimization  

Microsoft Academic Search

\\u000a A challenging problem in molecular biology is the identification of the specific binding sites of transcription factors in\\u000a the promoter regions of genes referred to as motifs. This paper presents an Ant Colony Optimization approach that can be used\\u000a to provide the motif finding problem with promising solutions. The proposed approach incorporates a modified form of the Gibbs\\u000a sampling technique

Salim Bouamama; Abdellah Boukerram; Amer F. Al-Badarneh

2010-01-01

116

FY005 Accomplishments for Colony Project  

SciTech Connect

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.

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

2005-07-05

117

Modeling of spatiotemporal patterns in bacterial colonies  

Microsoft Academic Search

A diffusion-reaction model for the growth of bacterial colonies is presented.\\u000aThe often observed cooperative behavior developed by bacteria which increases\\u000atheir motility in adverse growth conditions is here introduced as a nonlinear\\u000adiffusion term. The presence of this mechanism depends on a response which can\\u000apresent hysteresis. By changing only the concentrations of agar and initial\\u000anutrient, numerical integration

A. M. Lacasta; I. R. Cantalapiedra; C. E. Auguet; A. Penaranda; L. Ramirez-Piscina

1999-01-01

118

The Development of Politics in Extraterrestrial Colonies  

NASA Astrophysics Data System (ADS)

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.

Sivier, D. J.

119

Experimental Study for Automatic Colony Counting System Based Onimage Processing  

NASA Astrophysics Data System (ADS)

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

Fang, Junlong; Li, Wenzhe; Wang, Guoxin

120

Wading birds as biological indicators 1975 colony survey  

USGS Publications Warehouse

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.

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

1977-01-01

121

Respiratory disease in a colony of rats  

PubMed Central

An epidemic of acute respiratory disease in a colony of CFE rats is described, the main laboratory findings are recorded and its aetiology discussed. The epidemic showed that severe respiratory disease varying from peracute to chronic was associated with infection of the lungs with a mycoplasma but that mycoplasmas could be present in rats, even in the lungs, without signs of disease, thus suggesting that one or more other factors were involved. It is also evident that there are strain differences in the susceptibility of rats to this disease.

Lane-Petter, W.; Olds, R. J.; Hacking, M. R.; Lane-Petter, M. E.

1970-01-01

122

Combined Final Report for Colony II Project  

SciTech Connect

(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.

Kale, Laxmikant [University of Illinois] [University of Illinois; Jones, Terry [Oak Ridge National Laboratory] [Oak Ridge National Laboratory; Moreira, Jose [IBM Corp.] [IBM Corp.

2013-10-23

123

Intercellular Genomics of Subsurface Microbial Colonies  

SciTech Connect

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 equations and up-scaled advective-diffusive transport equations for chemical species. We are rigorously testing the relationship between these two scales by evaluating macroscopic parameters using the volume averaging methodology applied to pore scale model results.

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

2007-02-14

124

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

PubMed

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

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

2011-01-01

125

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

PubMed Central

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% (? = 8.55%) of the manually counted colonies, while an automated method based on a single-threshold segmentation procedure estimated an average of 76% (? = 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.

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

1998-01-01

126

From snowflake formation to growth of bacterial colonies II: Cooperative formation of complex colonial patterns  

Microsoft Academic Search

In nature, bacterial colonies must often cope with hostile environmental conditions. To do so they have developed sophisticated cooperative behaviour and intricate communication capabilities, such as direct cell- cell physical interactions via extra-membrane polymers, collective production of extracellular 'wetting' fluid for movement on hard surfaces, longrange chemical signalling such as quorum sensing and chemotactic (bias of movement according to gradient

Eshel Ben-Jacob

1997-01-01

127

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

ERIC Educational Resources Information Center

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…

Barker, Adam J.

2009-01-01

128

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

ERIC Educational Resources Information Center

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 which the…

Riney, Timothy J.

1998-01-01

129

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

PubMed

The Jackson Laboratory Colony Management System (JCMS) is a software application for managing data and information related to research mouse colonies, associated biospecimens, and experimental protocols. JCMS runs directly on computers that run one of the PC Windows operating systems, but can be accessed via web browser interfaces from any computer running a Windows, Macintosh, or Linux operating system. JCMS can be configured for a single user or multiple users in small- to medium-size work groups. The target audience for JCMS includes laboratory technicians, animal colony managers, and principal investigators. The application provides operational support for colony management and experimental workflows, sample and data tracking through transaction-based data entry forms, and date-driven work reports. Flexible query forms allow researchers to retrieve database records based on user-defined criteria. Recent advances in handheld computers with integrated barcode readers, middleware technologies, web browsers, and wireless networks add to the utility of JCMS by allowing real-time access to the database from any networked computer. PMID:20140675

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

2010-04-01

130

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

ERIC Educational Resources Information Center

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…

Richardson, Troy A.

2012-01-01

131

Murine bone marrow cell line producing colony-stimulating factor  

SciTech Connect

A cell line (H-1) derived from the adherent layer of a 14-wk-old Dexter bone marrow culture has been maintained as cloned and uncloned lines through 21 passages at the time of these studies. These cell lines develop many fat droplets as they age and become confluent. The uncloned line produces increasing amounts of colony-stimulating activity as the cells become confluent. Feeder-layers or supernatants from the nonconfluent or confluent fat-laden cells stimulate the formation of greater numbers of colonies derived from cultures of colony-forming units (CFU) than does medium from L cell culture containing colony-stimulating factor (CSF). Antibody to the CSF-containing medium from L cell culture neutralizes the colony-stimulating activity, thus showing immunologic similarity to a known molecular species that stimulates colony production in a CFU culture that produces granulocyte or macrophage populations, or both.

Harigaya, K. (Brookhaven National Lab., Upton, NY); Cronkite, E.P.; Miller, M.E.; Shadduck, R.K.

1981-11-01

132

Under colonialism to democratization: Early childhood development in Ghana  

Microsoft Academic Search

This work chronicles the phases of early childhood development in Ghana. This West African country experienced a change in\\u000a education after the inception of colonialism. Education of the very young became a part, though limited, of the missionary-based\\u000a education system under colonialism. The country moved from colonialism to a republic form of government in 1957. The republic\\u000a was determined and

Johnetta Wade Morrison

2000-01-01

133

Varroa-Virus Interaction in Collapsing Honey Bee Colonies  

PubMed Central

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.

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

2013-01-01

134

Hierarchy length in orphaned colonies of the ant Temnothorax nylanderi  

NASA Astrophysics Data System (ADS)

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.

Heinze, J.

2008-08-01

135

Efficient division and sampling of cell colonies using microcup arrays.  

PubMed

A microengineered array to sample clonal colonies is described. The cells were cultured on an array of individually releasable elements until the colonies expanded to cover multiple elements. Single elements were released using a laser-based system and collected to sample cells from individual colonies. A greater than an 85% rate in splitting and collecting colonies was achieved using a 3-dimensional cup-like design or "microcup". Surface modification using patterned titanium deposition of the glass substrate improved the stability of microcup adhesion to the glass while enabling minimization of the laser energy for splitting the colonies. Smaller microcup dimensions and slotting the microcup walls reduced the time needed for colonies to expand into multiple microcups. The stem cell colony retained on the array and the collected fraction within released microcups remained undifferentiated and viable. The colony samples were characterized by both reporter gene expression and a destructive assay (PCR) to identify target colonies. The platform is envisioned as a means to rapidly establish cell lines using a destructive assay to identify desired clones. PMID:23099535

Pai, Jeng-Hao; Kluckman, Kimberly; Cowley, Dale O; Bortner, Donna M; Sims, Christopher E; Allbritton, Nancy L

2013-01-01

136

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

PubMed Central

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.

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

2014-01-01

137

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

PubMed

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

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

2014-05-01

138

Chiral patterning in Paenibacillus colonies under stress  

NASA Astrophysics Data System (ADS)

One of the most striking examples of bacterial colony patterning occurs in the C-morphotype of Paenibacillus strains. Here, macroscopic chirality results from the interaction of local liquid-crystal ordering of the long bacterial cells with the self-propelled motility driven by the non-reflection-symmetric flagella. This talk will review some of the original experimental data from the Ben-Jacob lab as well as recent insight obtained via genomics. I will then discuss attempts to model and simulate the chiral patterns via solving reaction-diffusion equations on random lattices. At the end, I will introduce the challenges still to be faced in understanding transitions between these patterns and more common branching structures

Levine, Herbert

2012-02-01

139

Ant Colony Optimization with Cunning Ants  

NASA Astrophysics Data System (ADS)

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.

Tsutsui, Shigeyoshi

140

Optic disc detection using ant colony optimization  

NASA Astrophysics Data System (ADS)

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.

Dias, Marcy A.; Monteiro, Fernando C.

2012-09-01

141

Effects of worker genotypic diversity on honey bee colony development and behavior ( Apis mellifera L.)  

Microsoft Academic Search

There have been numerous reports of genetic influences on division of labor in honey bee colonies, but the effects of worker genotypic diversity on colony behavior are unclear. We analyzed the effects of worker genotypic diversity on the phenotypes of honey bee colonies during a critical phase of colony development, the “nest initiation” phase. Five groups of colonies were studied

Robert E. Page Jr; Gene E. Robinson; M. Kim Fondrk; Medhat E. Nasr

1995-01-01

142

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

PubMed Central

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)

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

1994-01-01

143

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

PubMed

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. PMID:20617585

Hjort, Jonas

2010-01-01

144

Idiocy and the Law in Colonial New England.  

ERIC Educational Resources Information Center

A review of laws and records of the courts of colonial New England indicates early laws of Massachusetts extended certain rights to idiots: they authorized the transfer of property, exonerated idiots who committed capital crimes, and extended relief to impoverished idiots. The relationship between colonial laws and present legislation is examined.…

Wickham, Parnel

2001-01-01

145

Solving permutation flow shop sequencing using ant colony optimization  

Microsoft Academic Search

This paper proposes an ant colony algorithm for permutation flow shop scheduling problem. The objective considered is to minimize makespan. Two priority rules are developed as heuristic information based on Johnson's Rule and total processing times. A local search is used for improving the constructed solutions. The proposed ant colony algorithm is tested on the benchmark problem set of Taillard.

Fardin Ahmadizar; Farnaz Barzinpour; Jamal Arkat

2007-01-01

146

Colony level sex allocation in a polygynous and polydomous ant  

Microsoft Academic Search

The colony-level sex allocation pattern of eusocial Hymenoptera has attracted much attention in recent studies of evolutionary biology. We conducted a theoretical and empirical study on this subject using the dolichoderine ant Technomyrmex albipes. This ant is unusual in having a dispersal polymorphism in both males and females. New colonies are founded by an alate female after mating with one

Kazuki Tsuji; Katsusuke Yamauchi

1994-01-01

147

Cooperative Formation of Chiral Patterns during Growth of Bacterial Colonies  

Microsoft Academic Search

Bacterial colonies can develop chiral morphology in which the colony consists of twisted branches, all with the same handedness. Microscopic observations of the chiral growth are presented. We propose that the observed (macroscopic) chirality results from the microscopic chirality of the flagella (via handedness in tumbling) together with orientation interaction between the bacteria. The above assumptions are tested using a

Eshel Ben-Jacob; Inon Cohen; Ofer Shochet; Adam Tenenbaum; András Czirók; Tamás Vicsek

1995-01-01

148

Continuous and discrete models of cooperation in complex bacterial colonies  

Microsoft Academic Search

We study the effect of discreteness on various models for patterning in bacterial colonies. In a bacterial colony with branching pattern, there are discrete entities - bacteria - which are only two orders of magnitude smaller than the elements of the macroscopic pattern. We present two types of models. The first is the Communicating Walkers model, a hybrid model composed

Inon Cohen; Ido Golding; Yonathan Kozlovsky; Eshel Ben-Jacob

1998-01-01

149

Lubricating bacteria model for branching growth of bacterial colonies  

Microsoft Academic Search

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

Yonathan Kozlovsky; Inon Cohen; Ido Golding; Eshel Ben-Jacob

1999-01-01

150

Application of LASCA technique for monitoring of bacterial colonies growth  

NASA Astrophysics Data System (ADS)

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.

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

2013-02-01

151

Nonrelatives inherit colony resources in a primitive termite.  

PubMed

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

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

2009-10-13

152

Sustainable virtual communities: suggestions from the colonial model  

Microsoft Academic Search

While virtual community research has contributed to the understanding of the virtual community sustainability, a need for a systematic model exists. In this paper, we propose a model of sustainable virtual communities based on the sustainability properties of animal colonies in nature. The premise of our model is that if we manage to replicate the sustainability properties of colonial systems

Jaana Porra; Michael S. Parks

2006-01-01

153

Detection and selective destruction of bacteria colony at THz frequencies  

Microsoft Academic Search

In this paper, theoretical investigation has been carried out to determine the usefulness of electromagnetic wave for detection and selective destruction of bacteria colony at THz frequencies. To carry out the investigation, a realistic three dimensional electrical model of bacteria colony has been developed and placed between a pair of dipole antennas designed at THz frequencies. The model is simulated

Sudhabindu Ray

2012-01-01

154

Discover for Yourself: An Optimal Control Model in Insect Colonies  

ERIC Educational Resources Information Center

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…

Winkel, Brian

2013-01-01

155

Emergency queen cell production in the honey bee colony  

Microsoft Academic Search

Summary Emergency queen cell production was examined in honey bee colonies of mixed European races. Thirteen colonies were dequeened and followed on a daily basis until after queen emergence. Observations were made on the number of cells, the temporal sequence of queen cell construction, cell location within the nest, the age of larvæ selected for queen rearing, mortality of immature

R. D. Fell; R. A. Morse

1984-01-01

156

Structural inverse analysis by hybrid simplex artificial bee colony algorithms  

Microsoft Academic Search

A hybrid simplex artificial bee colony algorithm (HSABCA) which combines Nelder–Mead simplex method with artificial bee colony algorithm (ABCA) is proposed for inverse analysis problems. The proposed algorithm is applied to parameter identification of concrete dam-foundation systems. To verify the performance of HSABCA, it is compared with the basic ABCA and a real coded genetic algorithm (RCGA) on two examples:

Fei Kang; Junjie Li; Qing Xu

2009-01-01

157

Division of labor during honey bee colony defense  

Microsoft Academic Search

Some worker honey bees respond to major disturbances of the colony by flying around the assailant and possibly stinging; they are a subset of the bees involved in colony defense. These defenders have an open-ended age distribution similar to that of foragers, but defensive behavior is initiated at a younger age than foraging is. Behavioral and genetic evidence shows that

Michael D. Breed; Gene E. Robinson; Robert E. Page

1990-01-01

158

The Legacy of Colonialism: Law and Women's Rights in India  

Microsoft Academic Search

The relationship between nineteenth century England and colonial India was complex in terms of negotiating the different constituencies that claimed an interest in the economic and moral development of the colonies. After India became subject to the sovereignty of the English Monarchy in 1858, its future became indelibly linked with that of England's, yet India's own unique history and culture

Varsha Chitnis; Danaya Wright

2007-01-01

159

Quantifying the colony shape of the Montastraea annularis species complex  

Microsoft Academic Search

The reef coral Montastraea\\u000a annularis has been used in a wide range of investigations. Recently, it has been recognized as a complex of three species based on field observations of the variation in colony shape. These observations have also been confirmed by molecular methods as well as morphometrics on individual corallites in the colonies. This paper presents a new quantitative

J. P. Dawson

2006-01-01

160

Indigenous Knowledge in the Science Curriculum: Avoiding Neo-Colonialism  

ERIC Educational Resources Information Center

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

Ryan, Ann

2008-01-01

161

Model Specification Searches Using Ant Colony Optimization Algorithms  

ERIC Educational Resources Information Center

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.

Marcoulides, George A.; Drezner, Zvi

2003-01-01

162

Modeling cell-matrix traction forces in Keratinocyte colonies  

NASA Astrophysics Data System (ADS)

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.

Banerjee, Shiladitya

2013-03-01

163

Simulation Studies on Harnessing of Artificial Ecosystems in Space Colonies  

Microsoft Academic Search

Space Colonies are an artificial habitation built in space, an idea first proposed by Gerard K. O'Neill in 1969. He suggested they be placed at Lagrange points which are points in space that balance out the gravitational attraction of the Earth and Moon. There are three types of space colonies proposed: Bernard, Cylinder, and Stanford Torus. The cylinder type, designed

Hiroyuki Miyajima

2010-01-01

164

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...

165

Indian Education in the American Colonies, 1607-1783.  

ERIC Educational Resources Information Center

Indian schooling in colonial America was continuously immersed in the exchange between cultures that involved religion, land ownership, disease, alcohol, and warfare, and was molded by trade in furs and hides, and Indian slaves. In the past two decades American scholars have begun to reinterpret colonial North American Indian history and the…

Szasz, Margaret Connell

166

Colonial Education: A History of Education in Belize.  

ERIC Educational Resources Information Center

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…

Lewis, Karla

167

'Administering the Medicine': Progressive Education, Colonialism, and the State.  

ERIC Educational Resources Information Center

Draws comparisons between the Australian education directors, Frank Tate and Jacques Henry Abendanon. Discusses educational reform issues based on racial contexts and social, political, and cultural aspects in the British colony of Victoria and the Dutch colony of Java. Concludes that, though their politcal contexts are different, their views are…

Cote, Joost

2001-01-01

168

How natural infection by Nosema ceranae causes honeybee colony collapse.  

PubMed

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. PMID:18647336

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

169

Colony Collapse Disorder: Many Suspects, No Smoking Gun  

NSDL National Science Digital Library

Although more has been learned since colony collapse disorder (CCD) was first identified in mid-November 2006, the mystery remains. Some possibilitiescontamination with pollen from plants genetically modified to carry an insecticidal gene, radiation from cell phones, and perhaps even stress itselfcan probably be ruled out as contributory causes of CCD, but the cause of the bee colony losses remains unknown.

Myrna E. Watanabe (Science Writer;)

2008-05-01

170

Education and National Personae in Portugal's Colonial and Postcolonial Transition.  

ERIC Educational Resources Information Center

Traces the evolution of Portuguese national identity, 1926-74, in relation to its African colonies, particularly Mozambique, to demonstrate that colonialism enforces values, identities, and "hierarchies of domination" within the colonizing society as well as between colonizers and colonized peoples. Examines the role of education in shaping and…

Errante, Antoinette

1998-01-01

171

Edmund Smith House: A History, Colonial National Historical Park.  

National Technical Information Service (NTIS)

The Edmund Smith House on Lot 53 in Yorktown was a part of the late colonial and 1781 Yorktown scene, having been standing since 1751. The Federal government acquired it as part of the Blow property in October 1968 and made it a part of Colonial National ...

C. E. Hatch

1969-01-01

172

Ammonia Pulses and Metabolic Oscillations Guide Yeast Colony Development  

PubMed Central

On solid substrate, growing yeast colonies alternately acidify and alkalinize the medium. Using morphological, cytochemical, genetic, and DNA microarray approaches, we characterized six temporal steps in the “acid-to-alkali” colony transition. This transition is connected with the production of volatile ammonia acting as starvation signal between colonies. We present evidence that the three membrane proteins Ato1p, Ato2p, and Ato3p, members of the YaaH family, are involved in ammonia production in Saccharomyces cerevisiae colonies. The acid-to-alkali transition is connected with decrease of mitochondrial oxidative catabolism and by peroxisome activation, which in parallel with activation of biosynthetic pathways contribute to decrease the general stress level in colonies. These metabolic features characterize a novel survival strategy used by yeast under starvation conditions prevalent in nature.

Palkova, Zdena; Devaux, Frederic; Ricicova, Marketa; Minarikova, Lucie; Le Crom, Stephane; Jacq, Claude

2002-01-01

173

Iridovirus and Microsporidian Linked to Honey Bee Colony Decline  

PubMed Central

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.

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

174

Modulation of tumour colony growth by irradiated accessory cells.  

PubMed Central

The ability of human tumour cells to form colonies in soft agar is enhanced by the presence of autologous phagocytic/adherent cells. We investigated the effect of irradiation on the ability of the adherent cells to support human tumour colony formation. Relatively low doses of irradiation significantly increased the growth enhancing ability of adherent cells in 17/19 cases. The possibility that the enhancement was mediated by inactivation of radiosensitive contaminating lymphocytes was explored. Depletion of T lymphocytes from unirradiated adherent cells by a monoclonal antibody and complement resulted in little overall change in tumour colony growth. However, elimination of only the suppressor subset (OKT8+) of T lymphocytes resulted in increased colony growth relative to control values obtained with unirradiated adherent cells. In contrast, depletion of T lymphocytes from irradiated adherent cells by a pan T monoclonal antibody and complement decreased colony formation. Thus, the ability of irradiated macrophages to enhance tumour colony growth appeared to be mediated by a T lymphocyte. The effect of irradiation on isolated populations of macrophages and T lymphocytes was also examined. The enhanced ability of irradiated adherent cells to support tumor colony growth appeared to have been due to treatment of T lymphocytes alone. The results indicate that both adherent macrophages and lymphocytes may influence the growth of clonogenic human tumour cells.

Hamburger, A. W.; White, C. P.; Dunn, F. E.

1983-01-01

175

Between stigmatisation and regulation: prostitution in colonial Northern Vietnam.  

PubMed

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. PMID:20364443

Tracol-Huynh, Isabelle

2010-08-01

176

A View of Future Human Colonies on Mars  

NASA Astrophysics Data System (ADS)

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.

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

2003-01-01

177

Was Fundamental Education Another Form Of Colonialism?  

NASA Astrophysics Data System (ADS)

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.

Watras, Joseph

2007-01-01

178

Selective sweeps in growing microbial colonies  

PubMed Central

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.

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

2012-01-01

179

Polymerase chain reaction for verification of fluorescent colonies of Erwinia chrysanthemi and Pseudomonas putida WCS358 in immunofluorescence colony staining.  

PubMed

The potential of polymerase chain reaction (PCR) for verifying the identity of colonies stained by the immunofluorescence colony-staining (IFC) procedure was investigated. Using primers directed against conserved sequences of the pectate lyase-genes coding for isozymes PLa, PLd and PLe of Erwinia chrysanthemi, the authors confirmed the identity of 96% of 20 fluorescent target colonies, punched from IFC-stained samples with pure cultures. In pour plates with mixtures of Erw. chrysanthemi and non-target colonies from potato peel extracts, the identity of 90% of 113 target colonies was confirmed. Using primers directed against sequences of the ferric-pseudobactin receptor gene pupA of Pseudomonas putida WCS358, the identity of 96% of 22 target colonies was confirmed in IFC-stained samples with pure cultures. In pour plates with mixtures of Ps. putida WCS358 and non-target bacteria from compost extracts, the identity of 59% of 108 fluorescent colonies was confirmed by PCR. It was shown that components from non-target bacteria lowered the threshold level of PCR for Ps. putida WCS358 100-fold. PMID:8567494

van der Wolf, J M; van Beckhoven, J R; de Vries, P M; Raaijmakers, J M; Bakker, P A; Bertheau, Y; van Vuurde, J W

1995-11-01

180

Increased inter-colony fusion rates are associated with reduced COI haplotype diversity in an invasive colonial ascidian Didemnum vexillum.  

PubMed

Considerable progress in our understanding of the population genetic changes associated with biological invasions has been made over the past decade. Using selectively neutral loci, it has been established that reductions in genetic diversity, reflecting founder effects, have occurred during the establishment of some invasive populations. However, some colonial organisms may actually gain an ecological advantage from reduced genetic diversity because of the associated reduction in inter-colony conflict. Here we report population genetic analyses, along with colony fusion experiments, for a highly invasive colonial ascidian, Didemnum vexillum. Analyses based on mitochondrial cytochrome oxidase I (COI) partial coding sequences revealed two distinct D. vexillum clades. One COI clade appears to be restricted to the probable native region (i.e., north-west Pacific Ocean), while the other clade is present in widely dispersed temperate coastal waters around the world. This clade structure was supported by 18S ribosomal DNA (rDNA) sequence data, which revealed a one base-pair difference between the two clades. Recently established populations of D. vexillum in New Zealand displayed greatly reduced COI genetic diversity when compared with D. vexillum in Japan. In association with this reduction in genetic diversity was a significantly higher inter-colony fusion rate between randomly paired New Zealand D. vexillum colonies (80%, standard deviation ±18%) when compared with colonies found in Japan (27%, standard deviation ±15%). The results of this study add to growing evidence that for colonial organisms reductions in population level genetic diversity may alter colony interaction dynamics and enhance the invasive potential of newly colonizing species. PMID:22303442

Smith, Kirsty F; Stefaniak, Lauren; Saito, Yasunori; Gemmill, Chrissen E C; Cary, S Craig; Fidler, Andrew E

2012-01-01

181

Increased Inter-Colony Fusion Rates Are Associated with Reduced COI Haplotype Diversity in an Invasive Colonial Ascidian Didemnum vexillum  

PubMed Central

Considerable progress in our understanding of the population genetic changes associated with biological invasions has been made over the past decade. Using selectively neutral loci, it has been established that reductions in genetic diversity, reflecting founder effects, have occurred during the establishment of some invasive populations. However, some colonial organisms may actually gain an ecological advantage from reduced genetic diversity because of the associated reduction in inter-colony conflict. Here we report population genetic analyses, along with colony fusion experiments, for a highly invasive colonial ascidian, Didemnum vexillum. Analyses based on mitochondrial cytochrome oxidase I (COI) partial coding sequences revealed two distinct D. vexillum clades. One COI clade appears to be restricted to the probable native region (i.e., north-west Pacific Ocean), while the other clade is present in widely dispersed temperate coastal waters around the world. This clade structure was supported by 18S ribosomal DNA (rDNA) sequence data, which revealed a one base-pair difference between the two clades. Recently established populations of D. vexillum in New Zealand displayed greatly reduced COI genetic diversity when compared with D. vexillum in Japan. In association with this reduction in genetic diversity was a significantly higher inter-colony fusion rate between randomly paired New Zealand D. vexillum colonies (80%, standard deviation ±18%) when compared with colonies found in Japan (27%, standard deviation ±15%). The results of this study add to growing evidence that for colonial organisms reductions in population level genetic diversity may alter colony interaction dynamics and enhance the invasive potential of newly colonizing species.

Smith, Kirsty F.; Stefaniak, Lauren; Saito, Yasunori; Gemmill, Chrissen E. C.; Cary, S. Craig; Fidler, Andrew E.

2012-01-01

182

Pre-colonial Ethnic Institutions and Contemporary African Development*  

PubMed Central

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.

Michalopoulos, Stelios; Papaioannou, Elias

2013-01-01

183

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

NASA Astrophysics Data System (ADS)

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.

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

2002-09-01

184

Demographic Review of a Captive Colony of Callitrichids (Callithrix kuhlii)  

PubMed Central

Although reports on colony demographics for a variety of callitrichid species are available in the literature, to date there has not been a detailed examination of Wied’s black tufted-ear marmoset (Callithrix kuhlii). The purpose of this study is to present colony demographics for C. kuhlii from the University of Nebraska at Omaha’s Callitrichid Research Center from 1991 to 2002. C. kuhlii are currently held in a number of zoological parks in the United States and abroad; however, the University of Nebraska at Omaha held the only breeding colony in North America. Here we report data on lifespan, sex ratio, litter size, and interbirth interval (IBI) for that captive breeding colony.

ROSS, CORINNA N.; FITE, JEFFREY E.; JENSEN, HEATHER; FRENCH, JEFFREY A.

2010-01-01

185

Honeybee colony collapse due to Nosema ceranae in professional apiaries.  

PubMed

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. PMID:23765741

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

186

21 CFR 866.2170 - Automated colony counter.  

Code of Federal Regulations, 2013 CFR

... 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 counter. (a)...

2013-04-01

187

21 CFR 866.2180 - Manual colony counter.  

Code of Federal Regulations, 2013 CFR

... 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. (a)...

2013-04-01

188

Chemotaxis migration and morphogenesis of living colonies.  

PubMed

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. PMID:23807468

Ben Amar, Martine

2013-06-01

189

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

NASA Astrophysics Data System (ADS)

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.

MacKenzie Brown, C.

2010-06-01

190

Generic modelling of cooperative growth patterns in bacterial colonies  

Microsoft Academic Search

BACTERIAL colonies must often cope with unfavourable environmental conditions1,2. To do so, they have developed sophisticated modes of cooperative behaviour3-10. It has been found that such behaviour can cause bacterial colonies to exhibit complex growth patterns similar to those observed during non-equilibrium growth processes in non-living systems11; some of the qualitative features of the latter may be invoked to account

Eshel Ben-Jacob; Ofer Schochet; Adam Tenenbaum; Inon Cohen; Andras Czirók; Tamas Vicsek

1994-01-01

191

Mate fidelity and coloniality in waterbirds: a comparative analysis  

Microsoft Academic Search

Increased opportunities for information are one potential benefit of sociality. We apply this idea to the advantages of colonial\\u000a breeding in bird species that are typically monogamous within a breeding season but often form new pair-bonds in subsequent\\u000a seasons. Individuals may benefit from nesting in colonies at high density by identifying good-quality potential alternative\\u000a mates among their neighbours. The opportunities

Frédérique Dubois; Frank Cézilly; Mark Pagel

1998-01-01

192

Sex ratios in bumble bee colonies: Complications due to orphaning?  

Microsoft Academic Search

Highly male-biased investment ratios (1:2.86, F:M, biomass wet weight) were found among reproductives reared by 32 Bombus terricola colonies set out in the field and 35 B. melanopygus colonies held in laboratory confinement. The numerical sex ratios were almost identical for the two species (1 queen to 6.1 males). Most of the males were produced early in the season by

Robin E. Owen; F. H. Rodd; R. C. Plowright

1980-01-01

193

Decentralized control of drone comb construction in honey bee colonies  

Microsoft Academic Search

Honey bee colonies furnish their nests with two types of comb distinguished by cell size: large cells for rearing males (drone\\u000a comb) and small cells for rearing workers (worker comb). The bees actively regulate the relative quantity of each type, a\\u000a behavior likely to be important in setting a colony's sex ratio. Experimental analysis of the information pathways and control

Stephen C. Pratt

1998-01-01

194

Data mining with an ant colony optimization algorithm  

Microsoft Academic Search

This work proposes an algorithm for data mining called Ant-Miner (Ant Colony-based Data Miner). The goal of Ant-Miner is to extract classification rules from data. The algorithm is inspired by both research on the behavior of real ant colonies and some data mining concepts and principles. We compare the performance of Ant-Miner with CN2, a well-known data mining algorithm for

Rafael S. Parpinelli; Heitor S. Lopes; Alex Alves Freitas

2002-01-01

195

Modelling food and population dynamics in honey bee colonies.  

PubMed

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

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

2013-01-01

196

A simple procedure for identification of Clostridium botulinum colonies  

Microsoft Academic Search

For direct identification of toxigenic colonies ofClostridium botulinum type E, suspected colonies are uniformly suspended in a phosphate buffer containing 0.5% (w\\/v) gelatin and 0.05% (w\\/v) Tween 20. After centrifuging, the supernatant is tested for botulinal toxin by an enzyme-linked immunosorbent assay (ELISA). The assay is specific for this type as it did not react with culture filtrates of otherClostridium

M. Dezfulian

1993-01-01

197

The Granulocyte-Macrophage Colony-Stimulating Factors  

Microsoft Academic Search

The granulocyte-macrophage colony-stimulating factors are well-characterized specific glycoproteins that interact to control the production, differentiation, and function of two related white cell populations of the blood, the granulocytes and monocyte-macrophages. Widely produced in the body, these regulators probably play an important role in resistance to infections. The proliferation of myeloid leukemia cells remains dependent on stimulation by colony-stimulating factors, although

Donald Metcalf

1985-01-01

198

Steps toward space colonization - Colony location and transfer trajectories  

Microsoft Academic Search

The problem of optimal location of a space colony (or manufacturing center) is treated by consideration of a baseline transfer trajectory from the mass-catching point at L2 to high Earth orbit. Locations treated include the 2:1, 5:2, 7:3, and 3:1 resonances; nominal candidate orbits are found as periodic orbits in the restricted three-body problem. Optimal colony inclination is estimated via

T. A. Heppenheimer

1978-01-01

199

Threads: Collecting Cloth in the North American French Colonies  

Microsoft Academic Search

Trade of European-produced cloth and clothing enabled indigenous and non-indigenous inhabitants of colonial New France to\\u000a rethink the “hand-woven”, impacting how self could be presented through dress. At the same time, objects were being collected\\u000a in New France for cabinets of curiosities and museums. These different collections resonated in different ways through history,\\u000a subsequently influencing modern understandings of colonial cloth

Diana DiPaolo Loren

2008-01-01

200

Views of Older Native American Adults in Colonial New England  

Microsoft Academic Search

This study examines the perceptions and treatment of older Native American adults in colonial New England (1620–1783). Social\\u000a scientists have found that varying degrees of persistence and change have historically characterized Indian attitudes toward\\u000a older adults in communities located in the central and western United States. In regards to northeastern North America, historians\\u000a have learned that, during the colonial period,

Jason Eden; Naomi Eden

2010-01-01

201

Caste in Cuenca: Colonial Identity in the Seventeenth Century Andes  

Microsoft Academic Search

To explore the concept of identity in colonial Ecuador is to examine a multiplicity of ideas and ideologies. As a historical\\u000a archaeologist trained in North America I bring with me my training in Americanist anthropology and archaeology. As Eric Wolf\\u000a points out, the anthropologist works within a discipline that was forged in colonialism, and yet at the same time anthropology

Ross W. Jamieson

202

Remarks of Elliptic Curves Derived from Ant Colony Routing  

NASA Astrophysics Data System (ADS)

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.

Jung, Sangsu; Kim, Daeyeoul; Singh, Dhananjay

2011-09-01

203

Colony evaluation is not affected by drifting of drone and worker honeybees ( Apis mellifera L.) at a performance testing apiary  

Microsoft Academic Search

The impact of drifting workers and drones on evaluating performance data of honeybee (Apis mellifera carnica) colonies was studied using DNA microsatellites. Colony size, honey yield and colony level of infestation with Varroa jacobsoniwere evaluated from 30 queenright colonies. Individuals (n = 1359 workers from 38 colonies, n = 449 drones from 14 colonies) were genotyped using four DNA microsatellite

Peter Neumann; Robin F. A. Moritz; Dieter Mautz

2000-01-01

204

A Metagenomic Survey of Microbes in Honey Bee Colony Collapse Disorder  

Microsoft Academic Search

In colony collapse disorder (CCD), honey bee colonies inexplicably lose their workers. CCD has resulted in a loss of 50 to 90% of colonies in beekeeping operations across the United States. The observation that irradiated combs from affected colonies can be repopulated with naive bees suggests that infection may contribute to CCD. We used an unbiased metagenomic approach to survey

Diana L. Cox-Foster; Sean Conlan; Edward C. Holmes; Gustavo Palacios; Jay D. Evans; Nancy A. Moran; Phenix-Lan Quan; Thomas Briese; Mady Hornig; David M. Geiser; Vince Martinson; Dennis vanEngelsdorp; Abby L. Kalkstein; Andrew Drysdale; Jeffrey Hui; Junhui Zhai; Liwang Cui; Stephen K. Hutchison; Jan Fredrik Simons; Michael Egholm; Jeffery S. Pettis; W. Ian Lipkin

2007-01-01

205

Antipredator benefits of group living in colonial web-building spiders: the ‘early warning’ effect  

Microsoft Academic Search

The Mexican colonial web-building spider Metepeira incrassata is frequently attacked by predatory wasps from a number of families. Previous studies have shown that wasps often attack more than one spider during a ‘run’ on a colony, but capture success declines as colony size increases, and that spiders in the central core of the colony have lower risk (Rayor & Uetz

GEORGE W. UETZ; Jay Boyle; CRAIG S. HIEBER; R. Stimson Wilcox

2002-01-01

206

Does foraging efficiency vary with colony size in the fairy martin Petrochelidon ariel?  

Microsoft Academic Search

Colonial breeding occurs in a wide range of taxa, however the advantages promoting its evolution and maintenance remain poorly understood. In many avian species, breeding colonies vary by several orders of magnitude and one approach to investigating the evolution of coloniality has been to examine how potential costs and benefits vary with colony size. Several hypotheses predict that foraging efficiency

Peter Santema; Simon C. Griffith; Naomi E. Langmore; Jan Komdeur; Michael J. L. Magrath

2009-01-01

207

Spatial dynamics of colony interactions in young populations of the fire ant Solenopsis invicta  

Microsoft Academic Search

Newly founded colonies of the fire ant Solenopsis invicta compete intensely by brood raids, which result in a rapid reduction of colony density. Experimental plantings of colonies and analyses of sequential maps were used to examine the importance of spatial pattern in the dynamics of young populations. Colony positions were initially clumped in naturally founded cohorts, but were regular in

Eldridge S. Adams; Walter R. Tschinkel

1995-01-01

208

Colony growth and the ontogeny of worker polymorphism in the fire ant, Solenopsis invicta  

Microsoft Academic Search

Colony size and worker polymorphism (headwidth) were determined for fire ant colonies ranging from incipient to 12 years of age. Colonies grew approximately logistically, reaching half size between 21\\/2 and 31\\/2 yr and reaching their maximum size of about 220000 workers after 4 to 6 yr. Colony size showed strong seasonal variation. There was some evidence that growth rate may

Walter R. Tschinkel

1988-01-01

209

Estimation of intracolonial worker relationship in a honey bee colony ( Apis mellifera L.) using DNA fingerprinting  

Microsoft Academic Search

Summary The number and frequencies of subfamilies in a honey bee colony were determined by DNA fingerprinting. Queen and brood samples were taken from three colonies with artificially inseminated queens and from one colony with a naturally mated queen. UsingHae III restriction enzyme and (GATA)4 oligonucleotide, the number of subfamilies in the colonies with artificially inseminated queens corresponded with the

M. Haberl; R. F. A. Moritz

1994-01-01

210

Impact of Thelohania solenopsae (Microsporidia: Thelohaniidae) on Polygyne Colonies of Red Imported Fire Ants (Hymenoptera: Formicidae)  

Microsoft Academic Search

Three studies were conducted to assess the effects of the entomopathogen Thelohania solenopsae on polygynous, red imported Þre ant, Solenopsis invicta Buren, colonies. A total of 57 of 122 queens (46.7%) from nine, Þeld-collected, polygyne, S. invicta colonies, was infected with T. solenop- sae. Infection rate of queens for each colony ranged from 25 to 75%. Laboratory colonies of polygyne

David H. Oi; David F. Williams

2002-01-01

211

Infection of Red Imported Fire Ant (Hymenoptera: Formicidae) Colonies with the Entomopathogen Thelohania solenopsae (Microsporidia: Thelohaniidae)  

Microsoft Academic Search

Thelohania solenopsae Knell, Allen, & Hazard is an entomopathogenic microsporidium that infects imported fire ants. We documented artificially initiated transmission of T. solenopsae among colonies of the red imported fire ant, Solenopsis invicta Buren. Microsporidian transmission was initiated by providing colonies with brood (mixture of eggs, larvae, and pupae) from infected S. invicta colonies. Inoculated laboratory colonies of S. invicta

DAVID F. WILLIAMS; DAVID H. OI; GREGORY J. KNUE

212

Chemical induction of colony formation in a green alga (Scenedesmus acutus) by grazers (Daphnia)  

Microsoft Academic Search

The green alga, Scenedesmus acutus, grows in culture in unicellular form, but it forms colonies (coenobia) when exposed for 48 h to a chemical released by the grazer Daphnia magna. The colony-forming response can be evoked only in growing cells. The Daphnia factor affects colony size but not algal growth rate. The minimum concentration of Daphnia factor that induces colony

WINFRIED LAMPERT; KARL OTTO ROTHHAUPT; ERIC VON ELERT

1994-01-01

213

California gull chicks raised near colony edges have elevated stress levels  

USGS Publications Warehouse

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.

Herring, Garth; Ackerman, Joshua T.

2011-01-01

214

A function of polar flagellum and anisotropic growth in Vibrio alginolyticus early-phase colonies.  

PubMed

We continuously observed growth of Vibrio alginolyticus early-phase colonies on agar plates by phase-contrast microscopy. Two mutants defective in motility on solid surfaces were used in this study: one (YM4) can swim in liquid environments using its polar flagellum, and the other (NMB198) cannot swim because it lacks any flagella. We found that isolated colonies of YM4 were generally more circular than those of NMB198. This observation suggests that YM4 cells moved slightly within a colony by the function of their polar flagella. For clustered colonies, where the distance between the colonies was short (<50 microm), the colonies of YM4 grew rapidly along the line between them, but they grew slowly in the lateral directions. Some colonies of NMB198 grew toward neighboring colonies. These observations indicate colony-to-colony interaction. PMID:16732454

Sakamoto, Kuniko; Magariyama, Yukio; Isobe, Seiichiro

2006-06-01

215

Measurement of ammonia emissions from tropical seabird colonies  

NASA Astrophysics Data System (ADS)

The excreta (guano) of seabirds at their breeding colonies represents a notable source of ammonia (NH3) emission to the atmosphere, with effects on surrounding ecosystems through nitrogen compounds being thereby transported from sea to land. Previous measurements in temperate UK conditions quantified emission hotspots and allowed preliminary global upscaling. However, thermodynamic processes and water availability limit NH3 formation from guano, which suggests that the proportion of excreted nitrogen that volatilizes as NH3 may potentially be higher at tropical seabird colonies than similar colonies in temperate or sub-polar regions. To investigate such differences, we measured NH3 concentrations and environmental conditions at two tropical seabird colonies during the breeding season: a colony of 20,000 tern spp. and noddies on Michaelmas Cay, Great Barrier Reef, and a colony of 200,000 Sooty terns on Ascension Island, Atlantic Ocean. At both sites time-integrated NH3 concentrations and meteorological parameters were measured. In addition, at Ascension Island, semi-continuous hourly NH3 concentrations and micrometeorological parameters were measured throughout the campaign. Ammonia emissions, quantified using a backwards Lagrangian atmospheric dispersion model, were estimated at 21.8 ?g m-2 s-1 and 18.9 ?g m-2 s-1 from Michaelmas Cay and Ascension Island, respectively. High temporal resolution NH3 data at Ascension Island estimated peak hourly emissions up to 377 ?g NH3 m2 s-1. The estimated percentage fraction of total guano nitrogen volatilized was 67% at Michaelmas Cay and 32% at Ascension Island, with the larger value at the former site attributed to higher water availability. These values are much larger than published data for sub-polar locations, pointing to a substantial climatic dependence on emission of atmospheric NH3 from seabird colonies.

Riddick, S. N.; Blackall, T. D.; Dragosits, U.; Daunt, F.; Braban, C. F.; Tang, Y. S.; MacFarlane, W.; Taylor, S.; Wanless, S.; Sutton, M. A.

2014-06-01

216

Variation in Symbiodinium ITS2 Sequence Assemblages among Coral Colonies  

PubMed Central

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 K?ne'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.

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

217

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

SciTech Connect

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.

Not Available

1990-05-01

218

Colonie Interim Storage Site: Annual environmental report for calendar year 1990, Colonie, New York  

SciTech Connect

Environmental monitoring of the US Department of Energy's (DOE) Colonie Interim Storage Site (CISS) and surrounding area began in 1984. CISS is part of the Formerly Utilized Sites Remedial Action Program (FUSRAP), a DOE program to decontaminate or otherwise control sties where residual radioactive materials remain from the early years of the nation's atomic energy program or from commercial operations causing conditions that Congress has authorized DOE to remedy. The routine environmental monitoring program at CISS includes sampling networks for external gamma radiation exposures and for radium-226, throium-232, an total uranium concentrations in surface water, sediment, and groundwater. Additionally, the nonradiological parameters volatile and semivolatile organics, pesticides/polychlorinated biphenyls (PCBs), metals, total organic carbon (TOC), total organic halides (TOX), specific conductivity, and pH are measured in groundwater. 14 refs., 20 figs., 25 tabs.

Not Available

1991-09-01

219

Individuals in an osprey colony discriminate between high and low quality information  

Microsoft Academic Search

A potential benefit of living in a colony is that animals may gain information about the location of good foraging sites from other colony members1-3. The role of information transfer as a major benefit favouring the evolution of coloniality is, however, very poorly understood4. Information transfer has been demonstrated for only a few colonial vertebrate species5-7, but not all colonial

Erick Greene

1987-01-01

220

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

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.

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

1987-10-01

221

The American Colony in Jerusalem, 1870-2006  

NSDL National Science Digital Library

This tremendous collection from the Library of Congress brings together over 10,000 manuscripts, maps, and visual materials from about a hundred years of the American Colony in Jerusalem. These materials were gifted to the Library of Congress in 2004, and the collection consists of photographs, pamphlets, telegrams, letters, book manuscripts, diaries, and ephemera that talk about the colony, along with addressing the broader history of Palestine and the Middle East in the 19th and 20th centuries. One of the highlights of the site is a special feature on the Bertha Vester diaries. Vester was the principal leader of the American Colony from 1923 to 1968, and her 48 diaries make for fascinating reading. The site also includes a timeline of events, and essays like "The Vester Diaries" and "A Community in Jerusalem".

222

The Plymouth Colony Archive Project at the University of Virginia  

NSDL National Science Digital Library

This valuable Website offers a wealth of documentary materials from the original Plymouth Colony settlement. The archive presents an extensive collection of searchable, online texts, including "court records, Colony laws, biographical profiles of selected colonists, probate inventories, wills," and analyses of these primary materials. The Website also has photographs and a description of the ongoing archaeological and reconstruction work at the settlement site, historical illustrations from the 1911 text by Albert Christopher Addison, The Romantic Story of the Mayflower Pilgrims, a walking tour of the colony courtesy of a link to ArchNet at the University of Connecticut, and a list of links to a number of related Websites. Researchers will be happy to know the Archive is searchable.

Deetz, James F.; Deetz, Patricia S.

1998-01-01

223

Mechanically Driven Growth of Quasi-Two-Dimensional Microbial Colonies  

NASA Astrophysics Data System (ADS)

We study colonies of nonmotile, rod-shaped bacteria growing on solid substrates. In our model, bacteria interact purely mechanically, by pushing each other away as they grow, and consume a diffusing nutrient. We show that mechanical interactions control the velocity and shape of the advancing front, which leads to features that cannot be captured by established Fisher-Kolmogorov models. In particular, we find that the velocity depends on the elastic modulus of bacteria or their stickiness to the surface. Interestingly, we predict that the radius of an incompressible, strictly two-dimensional colony cannot grow linearly in time, unless it develops branches. Importantly, mechanical interactions can also account for the nonequilibrium transition between circular and branching colonies, often observed in the lab.

Farrell, F. D. C.; Hallatschek, O.; Marenduzzo, D.; Waclaw, B.

2013-10-01

224

Effects of introducing foxes and raccoons on herring gull colonies  

USGS Publications Warehouse

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.

Kadlec, J.A.

1971-01-01

225

Space colonies and the philosophy of space exploration  

NASA Astrophysics Data System (ADS)

Many space enthusiasts believe that the possibilities offered by space colonies clinch the case in favor of space exploration. Such possibilities, however, cannot by themselves surmount the central social and ideological objections against space exploration. Moreover, to justify the process by which we can determine whether space colonies are a good idea requires that we meet those objections first. This task is often attemped by pointing to the many unintended good results of previous exploration (the serendipity of science) and then extrapolating to the future. But social and ideologial critics need not be impressed by a purely historical case for serendipity. Fortunately, a philosophical analysis of scientific exploration reveals that serendipity is an essential aspect of it. This result provides a justification for exploring space. And in light of that justification, we can begin to evaluate the proposals for space colonies.

Munévar, Gonzalo

1986-08-01

226

Neonicotinoid pesticide reduces bumble bee colony growth and queen production.  

PubMed

Growing evidence for declines in bee populations has caused great concern because of the valuable ecosystem services they provide. Neonicotinoid insecticides have been implicated in these declines because they occur at trace levels in the nectar and pollen of crop plants. We exposed colonies of the bumble bee Bombus terrestris in the laboratory to field-realistic levels of the neonicotinoid imidacloprid, then allowed them to develop naturally under field conditions. Treated colonies had a significantly reduced growth rate and suffered an 85% reduction in production of new queens compared with control colonies. Given the scale of use of neonicotinoids, we suggest that they may be having a considerable negative impact on wild bumble bee populations across the developed world. PMID:22461500

Whitehorn, Penelope R; O'Connor, Stephanie; Wackers, Felix L; Goulson, Dave

2012-04-20

227

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

PubMed

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. PMID:22689306

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

2012-07-01

228

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

PubMed Central

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.

1983-01-01

229

Colony differences in response to trapping in roseate terns  

USGS Publications Warehouse

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.

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

1995-01-01

230

Response Ant Colony Optimization of End Milling Surface Roughness  

PubMed Central

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.

Kadirgama, K.; Noor, M. M.; Abd Alla, Ahmed N.

2010-01-01

231

Proliferation of haematopoietic colonies in serum-free cultures.  

PubMed

In eight patients with polycythaemia vera and 20 normals, mononuclear cells of the peripheral blood were cultured in methylcellulose with and without exogenously added erythropoietin. The cultures were set up with fetal calf serum and with a serum-free medium of unsaturated fatty acids, lecithin and cholesterol. In patients with polycythemia vera, we found a proliferation of haematopoietic colonies without erythropoietin in both culture systems which could not be seen in normals. The proliferation of endogenous colonies in serum-free media suggests that polycythaemia vera is a clonal disorder which can be modulated by serum factors and by erythropoietin. PMID:6192051

Heilmann, E; Helb, H D

1983-01-01

232

Generic model of morphological changes in growing colonies of fungi  

NASA Astrophysics Data System (ADS)

Fungal colonies are able to exhibit different morphologies depending on the environmental conditions. This allows them to cope with and adapt to external changes. When grown in solid or semisolid media the bulk of the colony is compact and several morphological transitions have been reported to occur as the external conditions are varied. Here we show how a unified simple mathematical model, which includes the effect of the accumulation of toxic metabolites, can account for the morphological changes observed. Our numerical results are in excellent agreement with experiments carried out with the fungus Aspergillus oryzae on solid agar.

López, Juan M.; Jensen, Henrik J.

2002-02-01

233

Generic model of morphological changes in growing colonies of fungi.  

PubMed

Fungal colonies are able to exhibit different morphologies depending on the environmental conditions. This allows them to cope with and adapt to external changes. When grown in solid or semisolid media the bulk of the colony is compact and several morphological transitions have been reported to occur as the external conditions are varied. Here we show how a unified simple mathematical model, which includes the effect of the accumulation of toxic metabolites, can account for the morphological changes observed. Our numerical results are in excellent agreement with experiments carried out with the fungus Aspergillus oryzae on solid agar. PMID:11863559

López, Juan M; Jensen, Henrik J

2002-02-01

234

Inhibition of Colony-spreading Activity of Staphylococcus aureus by Secretion of ?-Hemolysin*  

PubMed Central

Staphylococcus aureus spreads on the surface of soft agar, a phenomenon we termed “colony spreading.” Here, we found that S. aureus culture supernatant inhibited colony spreading. We purified ?-hemolysin (Hld, ?-toxin), a major protein secreted from S. aureus, as a compound that inhibits colony spreading. The culture supernatants of hld-disrupted mutants had 30-fold lower colony-spreading inhibitory activity than those of the parent strain. Furthermore, hld-disrupted mutants had higher colony-spreading ability than the parent strain. These results suggest that S. aureus negatively regulates colony spreading by secreting ?-hemolysin.

Omae, Yosuke; Sekimizu, Kazuhisa; Kaito, Chikara

2012-01-01

235

Experimental conversion of colony social organization by manipulation of worker genotype composition in fire ants ( Solenopsis invicta )  

Microsoft Academic Search

Previous studies have shown that colony social organization in Solenopsis invicta is under strong genetic control. Colonies containing some proportion of workers with the Bb or bb genotypes at the gene Gp-9 display polygyne social organization (multiple reproductive queens per colony), whereas colonies with only BB workers express monogyne organization (single reproductive queen per colony). The hypothesis that the presence

K. G. Ross; L. Keller

2002-01-01

236

A Study of Colonial Surrogates and Indigenous Others.  

ERIC Educational Resources Information Center

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…

Willard, William

1993-01-01

237

Colony founding by pleometrosis in the fire ant, Solenopsis invicta  

Microsoft Academic Search

Newly mated queens of the fire ant, Solenopsis invicta, found colonies either alone (haplometrosis) or by joining with other newly mated queens (pleometrosis). Surveys after mating flights showed that nests and queens were usually aggregated in space, that queens were aggregated among occupied nest chambers, and that the occurrence and degree of pleometrosis was related to the mean queen density.

Walter R. Tschinkel; Dennis F. Howard

1983-01-01

238

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

ERIC Educational Resources Information Center

"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 entertainment…

2002

239

Generating thermotolerant colonies by pairing Beauveria bassiana isolates.  

PubMed

Low thermotolerance in entomopathogenic fungi is the main impediment to their industrialization. This research, for the first time, describes the generation of a thermotolerant colony by pairing and subculturing (cycling) two Beauveria bassiana isolates without sexual reproduction. A mixture of B. bassiana ERL1578 and ERL1576 was inoculated on quarter-strength Sabouraud dextrose agar with yeast extract (¼SDAY). The paired culture (ERL1578 + 1576) was cycled three times to increase the frequency of possible hyphal fusion at the first cycle (c. 5/5 × 10(5) conidia), followed by a heat treatment as a selection pressure. Two non-paired isolates served as controls. Two morphologically different colonies (BbHet1 and BbHet2) were isolated from the pairing. BbHet1 colony had the highest conidial yield. BbHet2 had the most rapid mycelial growth and produced sponge-like mycelial masses (the others were flat), and its conidia were darker than the non-paired colonies under a microscope (400×). BbHet2 conidia had 60.7% germination after exposure to 45 °C for 60 min (the others had < 15%) without significant loss of virulence against Western flower thrips, Frankliniella occidentalis; however, there was a slight decrease in conidial yield. The new phenotypes formed suggested that a genetic variation happened as a result of heterokaryosis and/or recombination, more than environmental adaptation, when mixing different conidia. This methodology seems to be very useful for enhancing thermotolerance in fungi. PMID:22092818

Kim, Jae Su; Skinner, Margaret; Gouli, Svetlana; Parker, Bruce L

2011-11-01

240

Post-colonial perils: art and national impossibilities  

Microsoft Academic Search

The paper reflects on the tension that the process of sensing a nation brings to the formation of a post-colony in Southeast Asia. The “aesthetic” in this context creates forms of sensibility of the “national,” rendering it present in the world and endowing it with certain identity-effects. On the other hand, it also posits an exceptional singularity, at once discriminating

Patrick D. Flores

2011-01-01

241

The wealth of the Cape Colony: Measurements from probate inventories  

Microsoft Academic Search

The stylized view of the Dutch Cape Colony (1652-1795) is of a poor, subsistence economy, with little progress in the first 143 years of Dutch rule. New evidence from probate inventory and auction roll records show that previous estimates about wealth at the Cape are inaccurate. In contrast to earlier historical accounts, the inventories reveal evidence of an affluent, market-integrated

Johan Fourie

2012-01-01

242

High-Frequency Switching of Colony Morphology in Candida albicans  

Microsoft Academic Search

The pathogenic yeast Candida albicans switches heritably and at high frequency between at least seven general phenotypes identified by colony morphology on agar. Spontaneous conversion from the original smooth to variant phenotypes (star, ring, irregular wrinkle, hat, stipple, and fuzzy) occurs at a combined frequency of 1.4 × 10-4, but is increased 200 times by a low dose of ultraviolet

Bernice Slutsky; Jeffrey Buffo; David R. Soll

1985-01-01

243

Evidence of colonial nesting and `site fidelity' among ornithischian dinosaurs  

Microsoft Academic Search

Recent discoveries in the late Cretaceous (Campanian) Two Medicine Formation of western Montana indicate that some dinosaur species, like some modern species of birds and crocodiles, nested in colonies. I report here evidence that members of one species returned to the same nesting area for many years. There are also indications that, after hatching, some species remained in their respective

John R. Horner

1982-01-01

244

A novel clustering approach: Artificial Bee Colony (ABC) algorithm  

Microsoft Academic Search

Artificial Bee Colony (ABC) algorithm which is one of the most recently introduced optimization algorithms, simulates the intelligent foraging behavior of a honey bee swarm. Clustering analysis, used in many disciplines and applications, is an important tool and a descriptive task seeking to identify homogeneous groups of objects based on the values of their attributes. In this work, ABC is

Dervis Karaboga; Celal Ozturk

2011-01-01

245

A comparative study of Artificial Bee Colony algorithm  

Microsoft Academic Search

Artificial Bee Colony (ABC) algorithm is one of the most recently introduced swarm-based algorithms. ABC simulates the intelligent foraging behaviour of a honeybee swarm. In this work, ABC is used for optimizing a large set of numerical test functions and the results produced by ABC algorithm are compared with the results obtained by genetic algorithm, particle swarm optimization algorithm, differential

Dervis Karaboga; Bahriye Akay

2009-01-01

246

Artificial Bee Colony (ABC) Algorithm on Training Artificial Neural Networks  

Microsoft Academic Search

In this work, performance of the artificial bee colony algorithm, a recently proposed algorithm, has been tested on training on artificial neural networks which are widely used in signal processing applications and the performance of the algorithm has been compared to differential evolution and particle swarm optimization algorithms which are also population-based algorithms. Results show that ABC algorithm outperforms the

D. Karaboga; B. Akay

2007-01-01

247

Reentry trajectory planning optimization based on ant colony algorithm  

Microsoft Academic Search

An optimal trajectory is very important to reusable launch vehicle (RLV) which faces the critical heating and aero force when it comes back from outer space through the dense atmosphere. However, the trajectory planning is a sort of typically large scale and multi-constraint optimization problem. Ant colony algorithm is a new class of population algorithm which has the potential to

Zhang Qingzhen; Liu Cunjia; Yang Bo; Ren Zhang

2007-01-01

248

From Savage to Citizen: Education, Colonialism and Idiocy  

ERIC Educational Resources Information Center

In constructing a framework for the participation and inclusion in political life of subjects, the Enlightenment also produced a series of systematic exclusions for those who did not qualify: including "idiots" and "primitive races". "Idiocy" emerged as part of wider strategies of governance in Europe and its colonies. This opened up the…

Simpson, Murray K.

2007-01-01

249

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

ERIC Educational Resources Information Center

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…

Flint, Myron

250

Reproductive competition in queenless honey bee colonies ( Apis mellifera L.)  

Microsoft Academic Search

Previously we reported that there are subfamily differences in drone production in queenless honey bee colonies, but these biases are not always explained by subfamily differences in oviposition behavior. Here we determine whether these puzzling results are best explained by either inadequate sampling of the laying worker population or reproductive conflict among workers resulting in differential treatment of eggs and

Robert E. Page; Gene E. Robinson

1994-01-01

251

Recent Literature on Slavery in Colonial North America.  

ERIC Educational Resources Information Center

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)

Wright, Donald R.

2003-01-01

252

Ant system: optimization by a colony of cooperating agents  

Microsoft Academic Search

An analogy with the way ant colonies function has suggested the definition of a new computational paradigm, which we call ant system (AS). We propose it as a viable new approach to stochastic combinatorial optimization. The main characteristics of this model are positive feedback, distributed computation, and the use of a constructive greedy heuristic. Positive feedback accounts for rapid discovery

Marco Dorigo; Vittorio Maniezzo; Alberto Colorni

1996-01-01

253

Making Colonial Subjects: Education in the Age of Empire  

ERIC Educational Resources Information Center

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…

Hall, Catherine

2008-01-01

254

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

ERIC Educational Resources Information Center

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)

Hennessey, Gail Skroback

1994-01-01

255

Urban Economics, Conduit-Colonialism and Public Policy  

ERIC Educational Resources Information Center

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)

Hamilton, Charles V.

1972-01-01

256

Language Games and Schooling: Discourses of Colonialism in Kiribati Education  

ERIC Educational Resources Information Center

The present secondary education system in Kiribati is little changed from its establishment and growth through the colonial years when the island group was known as the Gilbert Islands. It is marked by a heavy emphasis on English language and a curriculum geared to place students in a limited labour market. It is also marked by an uneven…

Burnett, Greg

2005-01-01

257

Indian hospitals and government in the colonial Andes.  

PubMed

This article examines the reception of the early modern hospital among the indigenous people of the Andes under Spanish colonial rule. During the period covered by this study (sixteenth to mid-eighteenth centuries), the hospital was conceived primarily as a manifestation of the sovereign’s paternalistic concern for his subjects’ spiritual well being. Hospitals in the Spanish American colonies were organised along racial lines, and those catering to Indians were meant to complement the missionary endeavour. Besides establishing hospitals in the main urban centres, Spanish colonial legislation instituted hospitals for Indians in provincial towns and in small rural jurisdictions throughout the Peruvian viceroyalty. Indian hospitals often met with the suspicion and even hostility of their supposed beneficiaries, especially indigenous rulers. By conceptualising the Indian hospital as a tool of colonial government, this article investigates the reasons behind its negative reception, the work of adaptation that allowed a few of them to thrive, and the eventual failure of most of these institutions. PMID:24070345

Ramos, Gabriela

2013-04-01

258

OPTIMIZING BUS TRANSIT NETWORK WITH PARALLEL ANT COLONY ALGORITHM  

Microsoft Academic Search

This study develop an optimization model for bus transit network based on road network and zonal OD. The model aims at achieving minimum transfers and maximum passenger flow per unit length with line length and non-linear rate as constraints. The coarse-grain parallel ant colony algorithm (CPACA) is used to solve the problem. To effectively search the global optimal solution, we

Zhongzhen Yang; Chuntian Cheng; Chong Liu

2005-01-01

259

The impact of perennial cormorant colonies on soil phosphorus status  

Microsoft Academic Search

During the last decades, the population of cormorants in Northern Europe has grown rapidly due to protection. Their impact on vegetation has been recognized, as many trees containing cormorant colonies have collapsed, but their influence on the soil phosphorus (P) status and related ecological impacts have not been studied in details.In this study, total and plant available P (PTotal, POlsen)

Henrik Breuning-Madsen; Camilla Bloch Ehlers; Ole K. Borggaard

2008-01-01

260

Aztec and Colonial Archeological Potteries: A Study on Fired Techniques  

Microsoft Academic Search

Mexican pottery, used during the Prehispanic period, showed different improvements in its manufacturing for some centuries before the arrival of Spaniards in Mexico. After this, new fired techniques were used to make ceramics during the Colonial period. Their composition, manufacturing, and fired process have not been fully understood. Photoacoustic spectroscopy (PAS), X-ray energy dispersive spectroscopy (XEDS), X-ray, transmission electron microscopy

J. Jiménez-Pérez; A. Brancamontes Cruz; A. Cruz-Orea; J. G. Mendoza-Alvarez; A. Gordillo-Sol; H. Yee-Madeira

2006-01-01

261

Colony Collapse Disorder Progress Report. CCD Steering Committee, June 2010.  

National Technical Information Service (NTIS)

Mandated by the 2008 Farm Bill (Section 7204 (h) (4)), this second annual report on Honey Bee Colony Collapse Disorder (CCD) research progress represents the work of a large number of scientists from 8 Federal agencies, 2 state departments of agriculture,...

2010-01-01

262

A Colony of Highly Phosphorescent EarthWorms  

Microsoft Academic Search

IN the sheltered westward corner of a small grass-plat in this city there is a colony of highly phosphorescent earth-worms. The annelid is round, pellucid, slender, of a faint yellowish tint, is about two inches long, and is not flattened behind. I have been unable to distinguish segmentation. The worm is entirely luminous. The phosphorescence has precisely the bright greenish

J. Lloyd-Bozward

1897-01-01

263

Competitive Effects of Erythropoietin and Colony Stimulating Factor.  

National Technical Information Service (NTIS)

Recipient mice were x-irradiated and injected with nucleated cells one to five hrs later. Bone marrow cells were cultured and colonies were scored with a dissecting microscope. When plethoric mice or rats were used either as hosts for CFU-stimulating assa...

G. Van Zant E. Goldwasser

1977-01-01

264

On the performance of artificial bee colony (ABC) algorithm  

Microsoft Academic Search

Artificial bee colony (ABC) algorithm is an optimization algorithm based on a particular intelligent behaviour of honeybee swarms. This work compares the performance of ABC algorithm with that of differential evolution (DE), particle swarm optimization (PSO) and evolutionary algorithm (EA) for multi-dimensional numeric problems. The simulation results show that the performance of ABC algorithm is comparable to those of the

Dervis Karaboga; Bahriye Basturk

2008-01-01

265

Trophic Interactions in a High Arctic Snow Goose Colony  

Microsoft Academic Search

SYNOPSIS. We examined the role of trophic interactions in structuring a high arctic tundra community characterized by a large breeding colony of greater snow geese (Chen caerulescens atlantica). According to the exploitation ecosystem hypothesis of Oksanen et al. (1981), food chains are controlled by top-down interactions. However, because the arctic primary productivity is low, herbivore populations are too small to

GILLES GAUTHIER; J OEL BETY; J EAN-FRANCO ISGIROUX; LINE ROCHEFORT

2004-01-01

266

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

ERIC Educational Resources Information Center

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…

Ogden, Anthony

2008-01-01

267

American Colonial Life as Experienced through Daniel Defoe's "Moll Flanders."  

ERIC Educational Resources Information Center

Presents an interdisciplinary unit for high school students in which the students examine life in the American colonies. Focuses on "Moll Flanders" because the students find her to be a fascinating guide to the past, bringing history alive. Gives resources, a handout, and two timed writing assignments. (CMK)

Traubitz, Nancy

1999-01-01

268

Making Thirteen Colonies. A History of US. Book Two.  

ERIC Educational Resources Information Center

This history volume traces the development of the American colonies from the arrival of the first English settlers in North America to the establishment of the United States and the beginning of the westward expansion. The profusely illustrated text includes sidebars elaborating upon significant points. Maps help students locate and visualize…

Hakim, Joy

269

Allozymic variation in a north American colony of Cepaea nemoralis  

Microsoft Academic Search

Starch gel electrophoresis of foot-muscle extracts from over 400 individuals of the land snail Cepaea nemoralis collected from 10 different populations in the Lexington, Virginia, colony revealed nine scorable loci. Two of these, LAP II and PGM II, proved to be polymorphic with two and three alleles, respectively. Each of the populations surveyed was in Hardy-Weinberg equilibrium at both loci,

P F Brussard; G F McCracken

1974-01-01

270

Environmental and Genetic Determinants of Colony Morphology in Yeast  

PubMed Central

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.

Granek, Joshua A.; Magwene, Paul M.

2010-01-01

271

Science and Religion in Colonial America: The Early Days  

Microsoft Academic Search

The use of science to validate biblical accounts or prove the existence of God began in the United States with the publication of Cotton Mather's The Christian Philosopher. Cotton Mather is generally remembered for his role in the Salem Witch Trials but his contribution in bringing science to Colonial America is not well known. Mather had an extensive library, was

Bruce Kirk Oldfield

272

How natural infection by Nosema ceranae causes honeybee colony collapse  

Microsoft Academic Search

Summary 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

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

2008-01-01

273

AN APPLICATION OF ANT COLONY OPTIMIZATION TO IMAGE CLUSTERING  

Microsoft Academic Search

Content-based image retrieval can be dramatically improved by providing a good initial clustering of visual data. The problem of image clustering is that most current algorithms are not able to identify individual clusters that exist in different feature subspaces. In this paper, we propose a novel approach for subspace clustering based on Ant Colony Optimization and its learning mechanism. The

Tomas Piatrik; Ebroul Izquierdo

274

Mass Spectral Molecular Networking of Living Microbial Colonies  

SciTech Connect

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.

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

275

Detection and enumeration of Vibrio vulnificus by direct colony immunoblot.  

PubMed

A direct colony immunoblot method (DCI) for the enumeration of Vibrio vulnificus was developed. Bacterial colonies were transferred from agar plates to membranes, which were then dried and blocked with bovine serum albumin. Subsequently, the membranes were treated with anti-V. vulnificus H antibodies, washed and incubated with peroxidase-conjugated goat anti-rabbit IgG. After a final wash, the membranes were exposed to a substrate mixture containing H(2)O(2) which resulted in the development of a purple color by V. vulnificus colonies. The DCI detected all clinical and environmental V. vulnificus strains tested and did not cross-react with other Vibrio species including V. cholerae, V. parahaemolyticus, or V. fluvialis. The DCI was then compared to the DNA hybridization procedure (DNAH) using V. vulnificus agar plates inoculated with mixed cultures of V. vulnificus and V. parahaemolyticus and V. vulnificus-seeded oyster homogenates. Both DCI and DNAH detected 1 to 2 log colony forming units (CFU)/mL V. vulnificus mixed with 4 log CFU/mL V. parahaemolyticus. Both methods were comparable and demonstrated no significant statistical differences when enumerating V. vulnificus in mixed cultures or in oyster homogenates seeded with levels of V. vulnificus from 2 to 6 log CFU/mL. The DCI demonstrated clearer color development and was less time consuming than the DNAH. PMID:19200106

Senevirathne, R N; Janes, M E; Simonson, J G

2009-01-01

276

Existential Thoughts in Fanon's Post-Colonialism Discourse  

ERIC Educational Resources Information Center

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…

Yeh, Chuan-Rong

2013-01-01

277

Dynamic Optimization of Chemical Processes using Ant Colony Framework  

Microsoft Academic Search

Ant colony framework is illustrated by considering dynamic optimization of six important bench marking examples. This new computational tool is simple to implement and can tackle problems with state as well as terminal constraints in a straightforward fashion. It requires fewer grid points to reach the global optimum at relatively very low computational effort. The examples with varying degree of

J. Rajesh; Kapil Gupta; Hari Shankar Kusumakar; Vaidyanathan K. Jayaraman; Bhaskar D. Kulkarni

2001-01-01

278

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

ERIC Educational Resources Information Center

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…

Allender, Tim

2007-01-01

279

Repeated loss of coloniality and symbiosis in scleractinian corals  

PubMed Central

The combination of coloniality and symbiosis in Scleractinia is thought to confer competitive advantage over other benthic invertebrates, and it is likely the key factor for the dominance of corals in tropical reefs. However, the extant Scleractinia are evenly split between zooxanthellate and azooxanthellate species. Most azooxanthellate species are solitary and nearly absent from reefs, but have much wider geographic and bathymetric distributions than reef corals. Molecular phylogenetic analyses have repeatedly recovered clades formed by colonial/zooxanthellate and solitary/azooxanthellate taxa, suggesting that coloniality and symbiosis were repeatedly acquired and/or lost throughout the history of the Scleractinia. Using Bayesian ancestral state reconstruction, we found that symbiosis was lost at least three times and coloniality lost at least six times, and at least two instances in which both characters were lost. All of the azooxanthellate lineages originated from ancestors that were reconstructed as symbiotic, corroborating the onshore–offshore diversification trend recorded in marine taxa. Symbiotic sister taxa of two of these descendant lineages are extant in Caribbean reefs but disappeared from the Mediterranean before the end of the Miocene, whereas extant azooxanthellate lineages have trans-Atlantic distributions. Thus, the phyletic link between reef and nonreef communities may have played an important role in the dynamics of extinction and recovery that marks the evolutionary history of scleractinians, and some reef lineages may have escaped local extinction by diversifying into offshore environments. However, this macroevolutionary mechanism offers no hope of mitigating the effects of climate change on coral reefs in the next century.

Barbeitos, Marcos S.; Romano, Sandra L.; Lasker, Howard R.

2010-01-01

280

Problematic spaces, problematic races: defining ‘Europeans’ in late colonial India  

Microsoft Academic Search

This article considers how women and men acquired ‘European’ status in gender-specific ways in colonial India between the late nineteenth century and independence in 1947. Being considered ‘European’ in this setting required far more than ancestry and biological attributes, and depended heavily on class, culture, occupation and ongoing imperial border crossings that allowed individuals to maintain direct contact with Britain.

Elizabeth Buettner

2000-01-01

281

Patients with Methicillin-Resistant Staphylococcus aureus (MRSA) Infection - 21st Century Lepers  

PubMed Central

In the recent past, there has been a dramatic increase in the incidence of methicillin-resistant Staphylococcus aureus (MRSA) infections, especially community-associated methicillin-resistant S. aureus (CA-MRSA) infections. Many media descriptions of MRSA are sensational and focus on its potential for severe disease and contagiousness. Our objective is to describe psychological and social morbidity associated with MRSA infection via a case series of five patients with CA-MRSA infection. We also analyze the resulting stigmatization associated with being diagnosed with MRSA infection. We learned that patients describe a variety of stigmatization related to their diagnosis of MRSA, including being shunned at home and in the workplace. Patients describe being asked by family, colleagues, and clients to take extraordinary measures to prevent MRSA transmission. Consequences of MRSA diagnoses have included erosion or termination of key personal and business relationships. In conclusion, stigmatization resulting from the diagnosis of MRSA can have profound personal and social morbidity. Media and public health awareness of MRSA infection needs to be balanced with information about how MRSA transmission is usually preventable with simple hygienic measures.

Mozzillo, Kristin L.; Ortiz, Nancy; Miller, Loren G.

2009-01-01

282

The global distribution of ammonia emissions from seabird colonies  

NASA Astrophysics Data System (ADS)

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 emissions.

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

2012-08-01

283

Microfabricated Arrays for Splitting and Assay of Clonal Colonies  

PubMed Central

A microfabricated platform was developed for highly parallel and efficient colony picking, splitting and clone identification. A pallet array provided patterned cell colonies which mated to a second printing array composed of bridging microstructures formed by a supporting base and attached post. The posts enabled mammalian cells from colonies initially cultured on the pallet array to migrate to corresponding sites on the printing array. Separation of the arrays simultaneously split the colonies creating a patterned replica. Optimization of array elements provided transfer efficiencies greater than 90% using bridging posts of 30 ?m diameter and 100 ?m length and total colony numbers of 3000. Studies using five mammalian cell lines demonstrated that a variety of adherent cell types could be cultured and effectively split with printing efficiencies of 78–92%. To demonstrate the technique’s utility, clonal cell lines with siRNA knockdown of Coronin 1B were generated using the arrays and compared to a traditional FACS/Western Blotting-based approach. Identification of target clones required a destructive assay to identify cells with an absence of Coronin 1B brought about by the successful infection of interfering shRNA construct. By virtue of miniaturization and its parallel format, the platform enabled the identification and generation of 12 target clones from a starting sample of only 3900 cells and required only 5-man hours over 11 days. In contrast, the traditional method required 500,000 cells and generated only 5 target clones with 34-man hours expended over 47 days. These data support the considerable reduction in time, manpower and reagents using the miniaturized platform for clonal selection by destructive assay versus conventional approaches.

Gach, Philip C.; Xu, Wei; King, Samantha J.; Sims, Christopher E.; Bear, James; Allbritton, Nancy L.

2012-01-01

284

Microfabricated arrays for splitting and assay of clonal colonies.  

PubMed

A microfabricated platform was developed for highly parallel and efficient colony picking, splitting, and clone identification. A pallet array provided patterned cell colonies which mated to a second printing array composed of bridging microstructures formed by a supporting base and attached post. The posts enabled mammalian cells from colonies initially cultured on the pallet array to migrate to corresponding sites on the printing array. Separation of the arrays simultaneously split the colonies, creating a patterned replica. Optimization of array elements provided transfer efficiencies greater than 90% using bridging posts of 30 ?m diameter and 100 ?m length and total colony numbers of 3000. Studies using five mammalian cell lines demonstrated that a variety of adherent cell types could be cultured and effectively split with printing efficiencies of 78-92%. To demonstrate the technique's utility, clonal cell lines with siRNA knockdown of Coronin 1B were generated using the arrays and compared to a traditional FACS/Western Blotting-based approach. Identification of target clones required a destructive assay to identify cells with an absence of Coronin 1B brought about by the successful infection of interfering shRNA construct. By virtue of miniaturization and its parallel format, the platform enabled the identification and generation of 12 target clones from a starting sample of only 3900 cells and required only 5 man hours over 11 days. In contrast, the traditional method required 500,000 cells and generated only 5 target clones with 34 man hours expended over 47 days. These data support the considerable reduction in time, manpower, and reagents using the miniaturized platform for clonal selection by destructive assay versus conventional approaches. PMID:23153031

Gach, Philip C; Xu, Wei; King, Samantha J; Sims, Christopher E; Bear, James; Allbritton, Nancy L

2012-12-18

285

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

PubMed

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. PMID:10985038

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

2000-08-01

286

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

SciTech Connect

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.

Not Available

1992-09-01

287

The Spanish Empire and its legacy: fiscal redistribution and political conflict in colonial and post-colonial Spanish America  

Microsoft Academic Search

The comparative history of the Americas has been used to identify factors determining longterm economic growth. One approach, new institutional economics (NIE), claims that the colonial origins of respective institutional structures explain North American success and Spanish American failure. Another argues that differences in resources encountered by Europeans fostered divergent levels of equality impacting on institutions and growth. This paper

Regina Grafe; Maria Alejandra Irigoin

2006-01-01

288

Comparative studies on the characteristics of proliferation and differentiation of spleen colony-forming cells  

SciTech Connect

Using a single spleen colony transplantation technique and sex chromosome typing as a natural cytogenetic marker, most spleen colony-forming cells (CFC) in adult bone marrow or fetal livers of inbred LACA or C57 mice re-established hemopoiesis in lethally irradiated mice when the spleen colonies were sampled at 13 days after transplantation. However, most of the spleen colony-forming cells in the peripheral blood of normal mice possess little potential for proliferation and are less efficient in the re-establishment of hemopoiesis in lethally irradiated mice. The CFC population is heterogeneous in the mice. From the subsequent retransplantation of colonies from colony-forming cells in the peripheral blood, the simple assessment of spleen colony-forming units (CFU-s) content, based on the number of splenic colonies, does not reliably represent the content of hemopoietic stem cells.

Wu, C.T.; Liu, M.P.; Chu, J.P.

1985-11-01

289

Nest site and weather affect the personality of harvester ant colonies  

PubMed Central

Environmental conditions and physical constraints both influence an animal's behavior. We investigate whether behavioral variation among colonies of the black harvester ant, Messor andrei, remains consistent across foraging and disturbance situations and ask whether consistent colony behavior is affected by nest site and weather. We examined variation among colonies in responsiveness to food baits and to disturbance, measured as a change in numbers of active ants, and in the speed with which colonies retrieved food and removed debris. Colonies differed consistently, across foraging and disturbance situations, in both responsiveness and speed. Increased activity in response to food was associated with a smaller decrease in response to alarm. Speed of retrieving food was correlated with speed of removing debris. In all colonies, speed was greater in dry conditions, reducing the amount of time ants spent outside the nest. While a colony occupied a certain nest site, its responsiveness was consistent in both foraging and disturbance situations, suggesting that nest structure influences colony personality.

Gordon, Deborah M.; Holmes, Susan

2012-01-01

290

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

USGS Publications Warehouse

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

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

1988-01-01

291

Varroa destructor Infestation in Untreated Honey Bee (Hymenoptera: Apidae) Colonies Selected for Hygienic Behavior  

Microsoft Academic Search

Honey bee (Apis mellifera L.) colonies bred for hygienic behavior were tested in a large field trial to determine if they were able to resist the parasitic mite Varroa destructor better than unselected colonies of \\

Marla Spivak; Gary S. Reuter

2001-01-01

292

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

PubMed

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. PMID:24037899

Steinmetz, George

2013-01-01

293

Unusual Colonies of 'Ureaplasma Urealyticum' (T Mycoplasmas) in Primary Agar Cultures of Certain Urine Specimens.  

National Technical Information Service (NTIS)

The existence of unusual colonies of Ureaplasma urealyticum (T mycoplasmas) in primary agar cultures of certain urine specimens is reported and their morphology is illustrated. The occurrence of such unusual colonies of U. urealyticum in agar cultures of ...

M. C. Shepard C. D. Lunceford

1975-01-01

294

Geographic structure of ade??lie penguin populations: Overlap in colony-specific foraging areas  

USGS Publications Warehouse

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 the study, when foraging trips of the large colony were very long, parents lost mass, and chick meals were smaller. In light of existing data on prey abundance in neritic waters in Antarctica suggesting that krill are relatively evenly distributed and in high abundance in the Southern Ross Sea, we conclude that penguins depleted or changed the availability of their prey, that the degree of alteration was a function of colony size, and that the large colony affected the location (and perhaps ultimately the size) of foraging areas for the smaller colonies. It appears, therefore, that foraging dynamics play a role in the geographic structuring of colonies in this species. ?? 2004 by the Ecological Society of America.

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

295

Alate production and sex ratio in colonies of the Neotropical termite Nasutitermes corniger (Isoptera; Termitidae)  

Microsoft Academic Search

1.Dissections of 49 entire Nasutitermes corniger (Motschulsky) colonies collected in Panama immediately prior to the nuptial flights give data on numbers, biomass and sex ratio of alates produced by individual colonies.2)Twenty-six other colonies were collected and dissected in the early period of alate nymph development. Alate nymphs proceed through five instars, spending 5–8 months within the parental colony.3)Even when comparing

Barbara L. Thorne

1983-01-01

296

Response of Reticulitermes hesperus (Isoptera: Rhinotermitidae) colonies to baiting with lufenuron in northern California.  

PubMed

The objective of this study was to evaluate lufenuron termite bait (1,500 ppm) for the elimination of colonies of Reticulitermes hesperus Banks (Isoptera: Rhinotermitidae). Dispersion of colonies in six baited and six unbaited sites near Placerville, CA, was determined by genetic (microsatellite) analyses. Twenty-one colonies of R. hesperus inhabited the six baited sites and eight colonies of R. hesperus occurred in the six unbaited sites. Five criteria provided a cause-and-effect link between the deployment of lufenuron termite bait and elimination of baited colonies: 1) association of foragers, as members of the same colony, in the independent monitoring stations and bait stations; 2) quantity of bait consumed; 3) abnormal physical appearance of foragers in bait stations; 4) disappearance of foragers from, and cessation of feeding in, independent monitoring stations visited by baited colonies; and 5) presence of foragers from, and continuation of feeding in, independent monitors visited by unbaited colonies. Baited colonies were devoid of foraging termites within a mean of 70.6 d (range, 37-93 d) of bait deployment. Colonies consumed a mean of 8.0 g of bait (range, 2.2-16.0 g). Wood consumption by baited and unbaited colonies was not significantly different during the 2 mo before baiting, 281.4 versus 590.5 mg/d per colony, respectively, nor during the 3 mo immediately after baiting, 112.5 versus 436.8 mg/d per colony, respectively. However, from 10 to 16 mo after baiting, wood consumption by baited colonies essentially ceased and was significantly less than the unbaited colonies, 7.9 versus 470.1 mg/d per colony, respectively. PMID:20568623

Haverty, Michael I; Tabuchi, Robin L; Vargo, Edward L; Cox, David L; Nelson, Lori J; Lewis, Vernard R

2010-06-01

297

Phenotypic sorting in morphology and reproductive investment among sociable weaver colonies  

Microsoft Academic Search

Colony sizes in birds can vary by orders of magnitude within species, and many studies have shown that selection pressures\\u000a differ dramatically among small and large colonies. Does such selection result in phenotypic sorting at the level of individuals?\\u000a This study describes inter-colony differences in morphology and reproductive investment in a population of a highly colonial,\\u000a communal and sedentary African

Claire N. Spottiswoode

2007-01-01

298

Self-Localization of a Holon in the Reconfiguration Task Space of a Robotic Colony  

Microsoft Academic Search

This paper introduces a methodology developed for the self-localization of a holon, within the reconfiguration task space of its colony under a highly decentralized decision-making and colony reconfiguration control. Holons act as intelligent agents of a colony in this decentralized structure. We term such an n-holon colony where intelligent agents can self-localize in reconfiguration task space without their tasks within

Mehmet Durna; Aydan M. Erkmen; Ismet Erkmen

2000-01-01

299

Field trial of honey bee colonies bred for mechanisms of resistance against Varroa destructor  

Microsoft Academic Search

We compared colonies selectively bred for both hygienic behavior and Suppression of Mite Reproduction (HYG\\/SMR) with colonies\\u000a bred solely for hygienic behavior (HYG) and unselected control colonies. Colonies were evaluated for strength, brood viability,\\u000a removal of freeze-killed brood, honey production, mite loads on adult bees and within worker brood, and mite reproductive\\u000a success on worker brood for two years in

Abdullah Ibrahim; Gary S. Reuter; Marla Spivak

2007-01-01

300

Chemomodulation of cellular movement, collective formation of vortices by swarming bacteria, and colonial development  

Microsoft Academic Search

Bacterial colonies have developed sophisticated modes of cooperative behavior which enable them to respond to adverse growth conditions. It has been shown that such behavior can be manifested in formation of complex colonial patterns. Certain Bacillus species exhibit collective migration, “turbulent like” flow and emergence of whirlpools during colonial development. Here we present experimental observations of collective behavior and a

Eshel Ben-Jacob; Inon Cohen; András Czirók; Tamás Vicsek; David L. Gutnick

1997-01-01

301

Testing the blank slate hypothesis: why honey bee colonies accept young bees  

Microsoft Academic Search

Summary Special features facilitate the admission of new members, such as neonates, to otherwise closed animal societies. In eusocial insects, such as honeybees and paper wasps, young adults acquire a colony recognition phenotype from other colony members or nesting materials. Older adults must exempt them from expulsion during the acquisition period. Newly emerged adult honeybees gain tolerance in their colony

M. D. Breed; S. Perry; L. B. Bjostad

2004-01-01

302

OVERWINTERING PERFORMANCE OF HONEY BEE COLONIES HEAVILY INFESTED WITH ACARAPIS WOODI (RENNIE)  

Microsoft Academic Search

SUMMARY Three groups of honey bee colonies (N = 30) were overwintered on a mountainside (2800 M) in northeastern Mexico. Infestation levels of Acarapis woodi in the three groups averaged 0, 28.2 and 86.0 % for the control, moderately, and heavily infested colonies, respectively. Heavily infested colonies were 28 % smaller than controls (P < 0.01) in the fall. Adjusting

Frank A. EISCHEN

1987-01-01

303

Migration of bacteria to the edges of the colony under ultraviolet radiation  

Microsoft Academic Search

Living organisms exhibit remarkable cooperative behavior in response to environmental stress. Bacterial colonies growing on a nutrient-rich substrate have served as model systems for studying pattern formation and population dynamics in biological systems. We report a novel spatio-temporal response of a Bacillus subtilis colony initially growing under ambient conditions to ultraviolet (UV) radiation exposure. The growth of the colonies decreased,

Anna M. Delprato; Azadeh Samadani; Arshad Kudrolli

2001-01-01

304

The effect of drone comb on a honey bee colony'sproduction of honey  

Microsoft Academic Search

This study examined the impact on a colony's honey production of providing it with a nat- ural amount (20%) of drone comb. Over 3 summers, for the period mid May to late August, I mea- sured the weight gains of 10 colonies, 5 with drone comb and 5 without it. Colonies with drone comb gained only 25.2 ± 16.0 kg

Thomas D. Seeley

2002-01-01

305

Intracolonial behavioral variation in worker oviposition, oophagy, and larval care in queenless honey bee colonies  

Microsoft Academic Search

Summary Two experiments were performed to determine whether worker reproduction in queenless honey bee colonies is influenced by colony genetic structure. In Experiment 1, allozyme analyses of workers and worker-derived drone larvae revealed that in half the colonies, there were genotypic differences in worker egg-laying behavior (presumed to involve actual oviposition), but biases in drone production were not always consistent

Gene E. Robinson; Robert E. Page; M. Kim Fondrk

1990-01-01

306

Linear extension rate is independent of colony size in the coral Pocillopora damicornis  

Microsoft Academic Search

Measurements of the skeletal extension rate of branches of the reef coral Pocillopora damicornis showed that the linear extension rate is independent of colony size for colonies from 1.9 to 19 cm in diameter. Analysis of existing data from Western Australia, Samoa, the Great Barrier Reef and Hawaii supports the finding that linear extension is not related to colony size

Robert A. Kinzie III; Teresa Sarmiento

1986-01-01

307

Identification and Molecular Analysis of Rough-Colony-Specific Outer Membrane Proteins of Actinobacillus actinomycetemcomitans  

Microsoft Academic Search

Actinobacillus actinomycetemcomitans, a gram-negative bacterium isolated from the human mouth, has been implicated in the pathogenesis of early-onset periodontitis. Primary isolates cultured from subgingival plaque exhibit an adherent, rough colony phenotype which spontaneously converts to a nonadherent, smooth pheno- type upon in vitro subculture. The rough colony variant produces abundant fimbriae and autoaggregates, while the smooth colony variant is planktonic

ELAINE M. HAASE; JOYCE L. ZMUDA; FRANK A. SCANNAPIECO

1999-01-01

308

A Hybrid Strategy Based on Ant Colony and Taboo Search Algorithms for Fuzzy Job Shop Scheduling  

Microsoft Academic Search

A hybrid strategy base on ant colony and taboo search algorithms is proposed for fuzzy job shop scheduling purpose, which uses the ant colony algorithm as a global search algorithm, and adopt taboo search algorithms as a local search algorithm. TS algorithms have stronger ability of the local search, which can overcome the disadvantages of ant colony algorithms, so this

Xiaoyu Song; Yunlong Zhu; Chaowan Yin; Fuming Li

2006-01-01

309

Field experiments on colony foundation by Lasius niger (L.) and L. flavus (F.) (Hym., Formicidae)  

Microsoft Academic Search

Summary Queens ofLasius flavus (F.) andL. niger (L.) were observed to choose sunlit bare areas for colony foundation and shading was found to reduce their success in founding colonies. Large colonies of these species killed queens of the opposite species first thus favouring the co-existence brought about by their habitat selection.

A. J. Pontin

1960-01-01

310

Desert ‘wastes’ of the Maghreb: desertification narratives in French colonial environmental history of North Africa  

Microsoft Academic Search

The origins of the word ‘desertification’, most commonly attributed to Aubréville’s 1949 work on tropical African forests, may be traced back much earlier, to nineteenth-century French colonial North Africa. The concept of desertification was central to French colonial thinking about the North African environment. This paper argues that an environmental history of the Maghreb was constructed during the French colonial

Diana K. Davis

2004-01-01

311

Effect of time on colony odour stability in the ant Formica exsecta  

NASA Astrophysics Data System (ADS)

Among social insects, maintaining a distinct colony profile allows individuals to distinguish easily between nest mates and non-nest mates. In ants, colony-specific profiles can be encoded within their cuticular hydrocarbons, and these are influenced by both environmental and genetic factors. Using nine monogynous Formica exsecta ant colonies, we studied the stability of their colony-specific profiles at eight time points over a 4-year period. We found no significant directional change in any colony profile, suggesting that genetic factors are maintaining this stability. However, there were significant short-term effects of season that affected all colony profiles in the same direction. Despite these temporal changes, no significant change in the profile variation within colonies was detected: each colony's profile responded in similar manner between seasons, with nest mates maintaining closely similar profiles, distinct from other colonies. These findings imply that genetic factors may help maintain the long-term stability of colony profile, but environmental factors can influence the profiles over shorter time periods. However, environmental factors do not contribute significantly to the maintenance of diversity among colonies, since all colonies were affected in a similar way.

Martin, S. J.; Shemilt, S.; Drijfhout, F. P.

2012-04-01

312

Heavy metal residues in prefledgling black-crowned night-herons from three Atlantic coast colonies  

USGS Publications Warehouse

Aquatic birds may serve as indicators of regional metal contamination. Because the food of prefledgling herons (Nycticorax nycticorax ) comes only from areas near the colony, their tissues should reflect local metal contamination. The authors' hypothesis was that prefledgling herons from the Rhode Island colony should have higher concentrations of metals than do those from either the North Carolina or Massachusetts colonies.

Custer, T. W.; Mulhern, B. L.

1983-01-01

313

Nutritional stress due to habitat loss may explain recent honeybee colony collapses  

Microsoft Academic Search

In spite of the tremendous public interest in the recent large honeybee losses attributed to colony collapse disorder, there is still no definitive explanation for the phenomenon. With the hypothesis that nutritional stress due to habitat loss has played an important role in honeybee colony collapse, I analyze the land use data in United States to show that the colony

Dhruba Naug

2009-01-01

314

The Sedimentation of Buoyant Microcystis Colonies Caused by Precipitation with an Iron-Containing Colloid  

Microsoft Academic Search

Colonies of Microcystis aeruginosa have dominated the phytoplankton in Lund tube C, a limnetic enclosure in Blelham Tarn, English Lake District, during the summer and autumn in recent years. Following holomixis in autumn the previously buoyant colonies sedimented from the water column onto the bottom mud. In all samples gas vesicles, which provided the colonies with buoyancy, were present in

R. L. Oliver; R. H. Thomas; C. S. Reynolds; A. E. Walsby

1985-01-01

315

Self-sustaining mars colonies utilizing the north polar cap and the martian atmosphere  

Microsoft Academic Search

A revolutionary new concept for the early establishment of robust, self-sustaining Martian colonies is described. The colonies would be located on the North Polar Cap of Mars and utilize readily available water ice and the CO2 Martian atmosphere as raw materials to produce all of the propellants, fuel, air, water, plastics, food, and other supplies needed by the colony. The

James Powell; George Maise; John Paniagua

2001-01-01

316

Opportunistic Adaptation in Space-Based Robot Colonies: Application to Site Preparation  

Microsoft Academic Search

A necessary precursor to the human exploration of Mars is a continuouslyoperating robot colony that can function successfully over a period ofyears. Such a robot colony would be useful not only in increasing ourknowledge about Mars, but also in paving the way for human explorationby deploying the infrastructure needed to support humans. For theserobot colonies to be successful over a

Lynne E. Parker; David Jung; Terry Huntsberger; Paolo Pirjanian

2000-01-01

317

Atlas of Wading Bird and Seabird Nesting Colonies in Coastal Louisiana, Mississippi, and Alabama: 1983.  

National Technical Information Service (NTIS)

Aerial surveys of waterbird colonies in coastal Louisiana, Mississippi, and Alabama were conducted in May and June of 1983. The major objective of these surveys was to provide up-to-date locations of active colony sites. Historic colony sites reported in ...

C. E. Keller J. A. Spendelow R. D. Greer

1984-01-01

318

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

ERIC Educational Resources Information Center

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…

Greene, Jack P.

319

Conflicting Views on Fiat Currency: Britain and its North American Colonies in the Eighteenth Century  

Microsoft Academic Search

Great Britain and its North American colonies possessed radically different monetary systems in the eighteenth century, particularly in regard to the role of government fiat paper. Parliament issued on fiat monies because of the fear of irreversible depreciation. In contrast, colonial legislatures started issuing various forms of paper monies in the 1690s and some persisted through the 1770s. Every colony

Edwin J. Perkins

1991-01-01

320

South Sudan: institutional legacy of colonialism and the making of a new state  

Microsoft Academic Search

The paper argues that the post-colonial crisis of citizenship demands a rethinking of the paradigm of viewing colonialism simply as a system of economic exploitation to viewing colonialism as a political project that is anchored in law. The paper provides a historical and post-referendum analysis of the political division between North and South Sudan. As South Sudan seeks to build

Christopher Zambakari

2012-01-01

321

Establishment of fungus comb in Laboratory colonies of Macrotermes michaelseni and Odontotermes montanus (Isoptera, Macrotermitinae)  

Microsoft Academic Search

Summary Wonkers in incipient laboratory colonies ofMacrotermes michaelseni andOdontotermes montanus build fæcal combs but are unable to inoculate these combs with fungus. These combs are eaten up and the colonies die unless fungus comb from a field colony is introduced when the first workers start foraging. This study investigated whether workers of the two species could produce fungus comb when

Robert Sieber

1983-01-01

322

Egg-laying in monogynous and polygynous colonies of the termite Macrotermes michaelseni (Isoptera, Macrotermitidae)  

Microsoft Academic Search

Summary. Our report provides quantitative information on egg production of termites in correlation with the weight of queens and the degree of polygyny of a colony. We suggest that in Macrotermes michaelseni king weight may be used as an independent surrogate for colony age. Queens of a given age (= king of the same weight) were heavier in monogynous colonies

M. Kaib; M. Hacker; R. Brandl

2001-01-01

323

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

ERIC Educational Resources Information Center

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,…

Diallo, Ibrahima

2012-01-01

324

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

ERIC Educational Resources Information Center

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,…

Walther, Daniel Joseph

2013-01-01

325

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

USGS Publications Warehouse

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.

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

1980-01-01

326

Genetic stability and diversity of Pneumocystis carinii infecting rat colonies.  

PubMed Central

There is increasing molecular and antigenic evidence that Pneumocystis carinii organisms isolated from humans, ferrets, and rats are different species. In contrast, little is known about the extent of genetic diversity among P. carinii strains found within a single mammalian species. In the present study, electrophoretic karyotypes were obtained from P. carinii prepared from 10 chronically immunosuppressed rat colonies to investigate diversity at the chromosomal level. Most organism preparations produced patterns with 13 to 15 bands, but as many as 24 bands were observed in a few preparations. All bands separated between 700 and 300 kbp. Four distinct karyotype forms emerged from among the 13- to 15-band karyotypes of the 10 colonies sampled. Form 1 was shared by five rat strains from two vendors; form 2 was shared by two rat strains from the same vendor; and forms 3 and 4 were unique to their vendor colonies. Within a given rat colony, most rats harbored the same P. carinii karyotype. A survey of selected rat colonies showed that the karyotype within a vendor colony could remain stable over a period of 2 to 3 years. Hybridization of the blotted karyotypes with a repetitive DNA element isolated from rat-derived P. carinii and with single-copy gene probes showed that every chromosome in the karyotypes contained some repetitive DNA, and there was a general size concordance among the chromosomes carrying the unique gene loci. Differences in gene sequences, electrophoretic karyotypes, and hybridization profiles suggested that the immunosuppressed rats were infected by genetically distinct P. carinii strains. A provisional system of nomenclature for P. carinii that will permit differentiation of P. carinii organisms from the same mammalian host is discussed. These data show that all rats were not infected by a single type of P. carinii, that pulsed-field gradient electrophoresis can detect sufficient genetic diversity among the organism preparations to allow for characterization of the organisms, and that the genome of the organism within the rat host is relatively stable over time. Images

Cushion, M T; Kaselis, M; Stringer, S L; Stringer, J R

1993-01-01

327

Application of sampling criterion on numerical diffraction from bacterial colonies.  

PubMed

Numerical diffraction from a bacterial colony was investigated from the viewpoint of applying the sampling criterion for both spatial and frequency domains. Once the morphology information of a bacterial colony was given, the maximum diffraction angle was estimated to reveal the minimum and maximum length of both the imaging and aperture domains. Scalar diffraction modeling was applied to estimate the diffraction pattern, which provided that two phase functions were contributing to the phase modulation: chirp and Gaussian phase functions. Optimal sampling intervals for both phase functions were investigated, and the effect of violating these conditions was demonstrated. Finally, the Fresnel approximation was compared to the angular spectrum method for accuracy and applicability, which then revealed that the Fresnel approximation was valid for both large imaging distances and longer wavelengths. PMID:21614116

Bae, Euiwon; Bai, Nan; Hirleman, E Daniel

2011-05-20

328

Feeding flights of nesting wading birds at a Virginia colony  

USGS Publications Warehouse

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.

Erwin, R.M.

1984-01-01

329

Granulocyte Colony-Stimulating Factor Receptor Mutations in Myeloid Malignancy  

PubMed Central

Granulocyte colony-stimulating factor is a cytokine able to stimulate both myelopoiesis and hematopoietic stem cell mobilization, which has seen it used extensively in the clinic to aid hematopoietic recovery. It acts specifically via the homodimeric granulocyte colony-stimulating factor receptor (G-CSFR), which is principally expressed on the surface of myeloid and hematopoietic progenitor cells. A number of pathogenic mutations have now been identified in CSF3R, the gene encoding G-CSFR. These fall into distinct classes, each of which is associated with a particular spectrum of myeloid disorders, including malignancy. This review details the various CSF3R mutations, their mechanisms of action, and contribution to disease, as well as discussing the clinical implications of such mutations.

Liongue, Clifford; Ward, Alister Curtis

2014-01-01

330

The Leslie Brock Center for the Study of Colonial Currency  

NSDL National Science Digital Library

Based at the University of Virginia Department of Economics, the Leslie Brock Center for the Study of Colonial Currency makes the controversial work of the late Leslie V. Brock (1903-1985), Professor of History, College of Idaho, available for study. Fundamental sources of Brock's inquiries into colonial paper money practices, such as Ben Franklin's "Modest Enquiry into the Nature and Necessity of a Paper Currency" (1729) and Douglass's "Discourse on the Currencies of the American Plantations" (1740), are included in full text, as are current articles on American monetary history. Useful links to other monetary history chronologies, sites, bibliographies, and currency calculators are maintained by Roy Davies, Science Librarian at the University of Exeter, England.

1997-01-01

331

A Hybrid Ant Colony Algorithm for Loading Pattern Optimization  

NASA Astrophysics Data System (ADS)

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.

Hoareau, F.

2014-06-01

332

Improved Clonal Selection Algorithm Combined with Ant Colony Optimization  

NASA Astrophysics Data System (ADS)

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.

Gao, Shangce; Wang, Wei; Dai, Hongwei; Li, Fangjia; Tang, Zheng

333

Temporal variation in atmospheric ammonia concentrations above seabird colonies  

Microsoft Academic Search

Recent studies have shown that seabirds are an important source of ammonia (NH3) emissions in remote coastal ecosystems. Nesting behaviour, which varies between seabird species, is likely to be a major factor in determining the proportion of excreted nitrogen (N) volatilised to the atmosphere as NH3. A long-term NH3 monitoring programme was implemented at a Scottish seabird colony with a

T. D. Blackall; L. J. Wilson; J. Bull; M. R. Theobald; P. J. Bacon; K. C. Hamer; S. Wanless; M. A. Sutton

2008-01-01

334

Biogenic amines and division of labor in honey bee colonies  

Microsoft Academic Search

Brain levels of dopamine, serotonin, and octopamine were measured in relation to both age-related division of labor and inter-individual\\u000a differences in task specialization independent of age in honey bee colonies. The only differences among similarly aged bees\\u000a performing different tasks were significantly lower levels of dopamine in food storers than comb builders and significantly\\u000a lower levels of octopamine in soldiers

C. Wagener-Hulme; J. C. Kuehn; D. J. Schulz; G. E. Robinson

1999-01-01

335

C. V. Raman and Colonial Physics: Acoustics and the Quantum  

NASA Astrophysics Data System (ADS)

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.

Banerjee, Somaditya

2014-05-01

336

Isolation of a murine osteoclast colony-stimulating factor  

Microsoft Academic Search

Cultures of a cell line derived from a murine mammary carcinoma that induces hypercalcemia were examined for soluble products that could induce osteoclasts to differentiate from murine bone marrow cells. The serum-free culture supernatant of this cell line stimulated growth of colonies from bone marrow cells that exhibited tartrate-resistant acid phosphatase (TRAPase) activity. These TRAPase-positive cells demonstrated essential features of

M. Y. Lee; D. R. Eyre; W. R. A. Osborne

1991-01-01

337

Neural Network Ensemble Based Ant Colony Classification Rule Mining  

Microsoft Academic Search

Generalization ability and comprehensibility are very important for classification rule mining. This paper proposes an improved ant colony classification rule mining method named ant-classifier with strong comprehensibility. Neural network ensemble is with good generalization ability. A novel algorithm NeAnt is also proposed which integrates neural network ensemble and ant-classifier's merit. In the NeAnt, neural network ensemble is used for preprocessing

Chuan Chen; Youqing Chen; Junbing He

2006-01-01

338

Organochlorine residues in two Norwegian puffin (fratercula arctica) colonies  

Microsoft Academic Search

Residue levels of the chlorinated hydrocarbons hexachlorobenzene (HCB), polychlori?nated biphenyls (PCBs), ??, ??, and ??hexachlorocyclohexane (HCH), oxychlordane, trans?nonachlor, aldrin, and dieldrin in adult puffins (Fratercula arctica) from two colonies in Norway (Røst 67°30'N and Hornøy 70° 20'N) showing differences in breeding performance were compared in 1982. Furthermore, residue levels in puffin chicks from Røst in 1982, when breeding failed totally,

Kristian Ingebrigtsen; Janneche Utne Skaare; Sverre Weberg Teigen

1984-01-01

339

Pipelaying under way on 326 mile Colonial Pipeline Co. project  

Microsoft Academic Search

Construction of the $310 million, 40 in. loop from Atlanta, Ga., to Greensboro, N.C. is scheduled for yearend 1978 completion and will provide Colonial with 2.1 million bbl\\/day of capacity and a 36 to 40 in. line from Hebert, Tex., to Greensboro for transporting gasoline products, parallel to the original 36 in. distillates pipeline The main line pipe is to

Ives

1978-01-01

340

Introduction: The Politics of the North American Colonial in 2009  

Microsoft Academic Search

The common sense of empire is increasingly embedded in local, national, and international epistemologies. Counter-hegemonic\\u000a discourse must increasingly confront and challenge dominant paradigms, research, policy, and practice. To do so requires a\\u000a perspective that recognizes current discourses of “difference” and “resistance.” Across much of the planet in disparate sites,\\u000a ground-up resistance is in motion. As colonial relations are variegated, extended,

Arlo Kempf

341

Multi-ant colonies algorithms for the VRPSPDTW  

Microsoft Academic Search

The vehicle routing problem with simultaneous pickups and deliveries and time windows (VRP-SPDTWj is the problem of optimally integrating forward (good distribution) and reverse logistics (returning materials) for cost saving and environmental protection. We constructed a general mixed integer programming model of VRP-SPDTW We present an Improved Ant Colony System (ACS) for the VRPSPDTW (Vehicle Routing Problem with Simultaneous Pick-up

L. Boubahri; S.-A. Addouche; A. El Mhamedi

2011-01-01

342

Factors affecting aerobic colony counts for bottled water  

Microsoft Academic Search

The Canadian Official Method MFO-15 for aerobic colony counts of bottled waters and ice requires pour plating with plate count agar (PCA) tempered to 40–45°C and incubating 48 h at 35°C. The performance of hydrophobic grid membrane filters (HGMF), counted by computerized counter after 48 h incubation on various media, was compared against MFO-15 for 31 water samples collected across

L. J Parrington; A. N Sharpe

1998-01-01

343

Space Colony from a Commercial Asteroid Mining Company Town  

NASA Astrophysics Data System (ADS)

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.

Taylor, Thomas C.; Grandl, Werner; Pinni, Martina; Benaroya, Haym

2008-01-01

344

Improved ant colony algorithm and its simulation study  

NASA Astrophysics Data System (ADS)

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.

Wang, Zongjiang

2013-03-01

345

Mechanisms of social regulation change across colony development in an ant  

PubMed Central

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 signals, change dramatically over a colony's life cycle. At the ultimate level, our results emphasize the importance of factors besides relatedness in predicting the level of conflict within a colony. Our results also suggest policing may not be an important regulatory force at every stage of colony development. Changes relating to the life cycle of the colony are sufficient to account for major differences in social regulation in an insect colony. Mechanisms of conflict mediation observed in one phase of a social group's development cannot be generalized to all stages.

2010-01-01

346

Interferon and haemopoietic colony inhibitor responses to Poly I--Poly C in rabbits and hamsters  

PubMed Central

Intravenous or intraperitoneal inoculation of Poly I—Poly C into rabbits induced an inhibitor for rabbit bone marrow colony growth in the serum which associated with interferon after fractionation on Sephadex G-200. Inoculation of hamsters with Poly I—Poly C did not induce either inhibitor for hamster colonies or interferon. Other substances can cause colony inhibition besides interferon and these were detected in both normal rabbit and normal hamster serum. Colony inhibition shows some species specificity, but cross-inhibition of monkey and mouse colony growth was shown with rabbit inhibitor. It is suggested that the basic biological role of interferon may lie in the control of cellular differentiation.

McNeill, T. A.; Fleming, W. A.; McCance, D. J.

1972-01-01

347

Lubricating bacteria model for branching growth of bacterial colonies  

NASA Astrophysics Data System (ADS)

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.

Kozlovsky, Yonathan; Cohen, Inon; Golding, Ido; Ben-Jacob, Eshel

1999-06-01

348

Rates in vitro changes of gonococcal colony opacity phenotypes.  

PubMed Central

The rate of change of colony opacity phenotype was determined for 12 strains of Neisseria gonorrhoeae. The average rate of change was about 2 X 10(-3) per colony-forming unit per generation with a range of 0.2 X 10(-3) to 4 X 10(-3) per colony-forming unit per generation. Transition from opaque to transparent occurred at the same rate as transition from transparent to opaque. The following factors were shown to have no effect on the transition rate: (i) the state of piliation; (ii) the number of passages as a particular phenotype; (iii) alteration in the temperature, pH, or amount of oxygen in the atmosphere during growth; (iv) the addition of any of 194 compounds or mixtures to the growth media; (v) the addition of DNase or of DNA from opaque or transparent gonococci; and (vi) incubation between the opacity-transparency transition and the change resulting in the loss of piliation was seen. Some implications of the high transition rate are discussed.

Mayer, L W

1982-01-01

349

Colony disassociation following diet partitioning in a unicolonial ant  

NASA Astrophysics Data System (ADS)

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.

Silverman, J.; Liang, D.

2001-01-01

350

Rationality in collective decision-making by ant colonies  

PubMed Central

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.

Edwards, Susan C.; Pratt, Stephen C.

2009-01-01

351

Nerve growth factor promotes human hemopoietic colony growth and differentiation  

SciTech Connect

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

Matsuda, H.; Coughlin, M.D.; Bienenstock, J.; Denburg, J.A. (McMaster Univ. Health Sciences Center, Hamilton, Ontario (Canada))

1988-09-01

352

Towards a colony counting system using hyperspectral imaging  

NASA Astrophysics Data System (ADS)

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.

Masschelein, B.; Robles-Kelly, A.; Blanch, C.; Tack, N.; Simpson-Young, B.; Lambrechts, A.

2012-02-01

353

Organochlorine residues in two Norwegian puffin (Fratercula arctica) colonies.  

PubMed

Residue levels of the chlorinated hydrocarbons hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs), alpha-, beta-, and gamma-hexachlorocyclohexane (HCH), oxychlordane, trans-nonachlor, aldrin, and dieldrin in adult puffins (Fratercula arctica) from two colonies in Norway (Røst 67 degrees 30'N and Hornøy 70 degrees 20'N) showing differences in breeding performance were compared in 1982. Furthermore, residue levels in puffin chicks from Røst in 1982, when breeding failed totally, were compared with the corresponding levels in 1983, when breeding was successful. Residue levels of chlorinated hydrocarbons were also measured in eggs from Røst 1982. An autoradiographic study of the distribution of [14C]HCB in adult puffins and chicks from Røst 1982 was included. In general, organochlorine contamination was low, and the results are interpreted to eliminate the organochlorines as a serious factor for impaired reproduction in the Røst colony. Significant differences between the two colonies are discussed in relation to geographical and nutritional aspects. The finding of significantly higher levels of organochlorines in organ tissue from puffin chicks from Røst in 1982 compared to the corresponding levels in 1983 may reflect the dramatic difference in nutritional status between the two years. PMID:6084067

Ingebrigtsen, K; Skaare, J U; Teigen, S W

1984-01-01

354

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

PubMed Central

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

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

2008-01-01

355

Bird colonies cause seagrass enrichment in a subtropical estuary: Observational and experimental evidence  

NASA Astrophysics Data System (ADS)

Colonies/roosts of piscivorous birds in Florida Bay, a subtropical estuary, concentrate nutrients by feeding away from their colonies/roosts and returning with food for young and to defaecate. Seagrass beds surrounding the colony islands were markedly different from those around similar islands that did not contain colonies. Seagrass standing crop was enhanced up to 200 m from bird colony islands compared with islands without colonies. The species of seagrass were also different at colonies, where Halodule wrightii and Ruppia maritima predominated in zones close to the colony islands. Around islands without colonies, only Thalassia testudinum was present. Experimental bird perches placed to stimulate concentrated bird presence produced changes in adjacent seagrass meadows that were similar to differences between islands with colonies and those without. Over 5 years, seagrass standing crop increased around the experimental perches, and species dominance shifted from T. testudinum to H. wrightii. No similar changes occurred at control locations. These experimental results indicate that the bird concentrations are responsible for the observed differences in seagrass communities surrounding islands that contain colonies. These enriched areas are significant to the seagrass ecosystem because many seagrasses in Florida Bay appear to be nutrient-limited. Demersal fish and invertebrate density and species richness have been shown to be a function of the seagrass standing crop and species composition, so the changes in seagrasses stimulated by localized bird concentrations have the capacity to alter the entire community structure.

Powell, George V. N.; Fourqurean, James W.; Kenworthy, W. Judson; Zieman, Joseph C.

1991-06-01

356

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

USGS Publications Warehouse

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

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

2006-01-01

357

Effects of boric acid, fipronil, hydramethylnon, and diflubenzuron baits on colonies of ghost ants (Hymenoptera: Formicidae).  

PubMed

Laboratory colonies of the ghost ant, Tapinoma melanocephalum (F.) were administered sugar solution (10%) baits containing the insecticides boric acid, fipronil (REGENT), hydramethylnon (SIEGE), or diflubenzuron (DIMILN). Colonies were exposed to the baits for 21 d, and development of workers, queens, and brood (larvae and pupae) was observed for 4 wk. Fipronil (0.05%) caused 100% mortality in all colonies the first week. With boric acid (0.5%), 100% mortality of workers, queens, and brood was reached at the end of the third week. With hydramethylnon (2%), 83% of the colonies disappeared at the end of the fourth week, but some queens were still alive 9 wk after the trial started. Diflubenzuron (1%) behaved similarly to the control, although in some colonies, the brood production increased, whereas in other colonies, the queens disappeared. In the control colonies, workers, queens, and brood were always observed even up to 9 wk. PMID:12852627

Ulloa-Chacón, Patricia; Jaramillo, Gloria Isabel

2003-06-01

358

Simulation Studies on Harnessing of Artificial Ecosystems in Space Colonies  

NASA Astrophysics Data System (ADS)

Space Colonies are an artificial habitation built in space, an idea first proposed by Gerard K. O'Neill in 1969. He suggested they be placed at Lagrange points which are points in space that balance out the gravitational attraction of the Earth and Moon. There are three types of space colonies proposed: Bernard, Cylinder, and Stanford Torus. The cylinder type, designed by Gerard K. O'Neill, is the most popular in concept at 6 km diameter and 30 km length, corresponding to about 845 cubic km, ten thousand people would potentially be able to reside these. The habitation area would be rotated to generate a quasi-gravitation by centrifugal force. It would be rotated at 0.55 rpm to generate a gravitation equivalent to that of the earth. In the space colony, there would be six areas axially, consisting of flooring and windows alternately. Mobile mirrors would be located outside the windows to reflect sun light toward the habitation areas and generate day, night, and seasons within the space colony. Thus an artificial ecosystem would be created allowing people live in much the same way as they do on the earth. According to my former research on micro ecosystems, it is very difficult to keep the environment balanced at all points due to the large volume of the habitation area and the thermal input of the mobile mirrors. It is predicted that there will be differences in the environment at each point of the cylinder due to the mirror angle. Although controlling the whole artificial ecosystem balance is important, local environment control at each point is also important for people to live and work comfortably. Therefore, it is needed to develop simulation models which can study the whole ecosystem as well as local environments at each point at the same time. This model has to be able to simulate dynamics of the whole system as well as the local environments. In this study, I have developed a new model to simulate the whole and local dynamics in a space colony by using a cell automaton consisting of structure, thermal, air, water, and vegetation models.

Miyajima, Hiroyuki

359

Work plan for the remedial investigation/feasibility study-environmental assessment for the Colonie site, Colonie, New York  

SciTech Connect

This work plan has been prepared to document the scoping and planning process performed by the US Department of Energy (DOE) to support remedial action activities at the Colonie site. The site is located in eastern New York State in the town of Colonie near the city of Albany. Remedial action of the Colonie site is being planned as part of DOE's Formerly Utilized Sites Remedial Action Program. The DOE is responsible for controlling the release of all radioactive and chemical contaminants from the site. Under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), a remedial investigation/feasibility study (RI/FS) must be prepared to support the decision-making process for evaluating remedial action alternatives. This work plan contains a summary of information known about the site as of January 1988, presents a conceptual site model that identifies potential routes of human exposure to site containments, identifies data gaps, and summarizes the process and proposed studies that will be used to fill the data gaps. In addition, DOE activities must be conducted in compliance with the National Environmental Policy Act (NEPA), which requires consideration of the environmental consequences of a proposed action as part of its decision-making process. This work also describes the approach that will be used to evaluate potential remedial action alternatives and includes a description of the organization, project controls, and task schedules that will be employed to fulfill the requirements of both CERCLA and NEPA. 48 refs., 18 figs., 25 tabs.

Not Available

1990-06-01

360

Shiga Toxin 2 Induces Macrophage-Granulocyte Colonies from Human Bone Marrow and Cord Blood Stem Cells  

PubMed Central

Addition of Shiga toxin 2 to human bone marrow or cord blood cell culture induced macrophage-granulocyte colonies. Although Shiga toxin 2 alone induced colonies mainly composed of macrophages, it induced colonies mainly consisting of granulocytes when combined with physiological doses of interleukin-1?, granulocyte colony-stimulating factor, or stem cell factor with interleukin-3.

Chiyoda, Shin; Takeda, Tae; Aoki, Yosuke

2002-01-01

361

The effect of transformation temperature and prior austenite grain size on the pearlite colony size in vanadium treated pearlitic steels  

SciTech Connect

The lower the transformation temperature, the smaller the colony size. Over the range of transformation temperatures 660-580/sup 0/C, the ratio of the colony size to the mean true interlamellar spacing was in the range 29 to 35. The prior austenite grain size affected neither the pearlite colony size nor the structure of a colony but influenced the morphology of pearlite.

Pickering, F.B.; Garbarz, B.

1987-03-01

362

Varroa destructor infestation in untreated honey bee (Hymenoptera: Apidae) colonies selected for hygienic behavior.  

PubMed

Honey bee (Apis mellifera L.) colonies bred for hygienic behavior were tested in a large field trial to determine if they were able to resist the parasitic mite Varroa destructor better than unselected colonies of"Starline" stock. Colonies bred for hygienic behavior are able to detect, uncap, and remove experimentally infested brood from the nest, although the extent to which the behavior actually reduces the overall mite-load in untreated, naturally infested colonies needed further verification. The results indicate that hygienic colonies with queens mated naturally to unselected drones had significantly fewer mites on adult bees and within worker brood cells than Starline colonies for up to 1 yr without treatment in a commercial, migratory beekeeping operation. Hygienic colonies actively defended themselves against the mites when mite levels were relatively low. At high mite infestations (>15% of worker brood and of adult bees), the majority of hygienic colonies required treatment to prevent collapse. Overall, the hygienic colonies had similar adult populations and brood areas, produced as much honey, and had less brood disease than the Starline colonies. Thus, honey bees bred for hygienic behavior performed as well if not better than other commercial lines of bees and maintained lower mite loads for up to one year without treatment. PMID:11332821

Spivak, M; Reuter, G S

2001-04-01

363

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

PubMed

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. PMID:23710754

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

2013-06-01

364

Honeybee Colony Disorder in Crop Areas: The Role of Pesticides and Viruses  

PubMed Central

As in many other locations in the world, honeybee colony losses and disorders have increased in Belgium. Some of the symptoms observed rest unspecific and their causes remain unknown. The present study aims to determine the role of both pesticide exposure and virus load on the appraisal of unexplained honeybee colony disorders in field conditions. From July 2011 to May 2012, 330 colonies were monitored. Honeybees, wax, beebread and honey samples were collected. Morbidity and mortality information provided by beekeepers, colony clinical visits and availability of analytical matrix were used to form 2 groups: healthy colonies and colonies with disorders (n?=?29, n?=?25, respectively). Disorders included: (1) dead colonies or colonies in which part of the colony appeared dead, or had disappeared; (2) weak colonies; (3) queen loss; (4) problems linked to brood and not related to any known disease. Five common viruses and 99 pesticides (41 fungicides, 39 insecticides and synergist, 14 herbicides, 5 acaricides and metabolites) were quantified in the samples.The main symptoms observed in the group with disorders are linked to brood and queens. The viruses most frequently found are Black Queen Cell Virus, Sac Brood Virus, Deformed Wing Virus. No significant difference in virus load was observed between the two groups. Three acaricides, 5 insecticides and 13 fungicides were detected in the analysed samples. A significant correlation was found between the presence of fungicide residues and honeybee colony disorders. A significant positive link could also be established between the observation of disorder and the abundance of crop surface around the beehive. According to our results, the role of fungicides as a potential stressor for honeybee colonies should be further studied, either by their direct and/or indirect impacts on bees and bee colonies.

Simon-Delso, Noa; San Martin, Gilles; Bruneau, Etienne; Minsart, Laure-Anne; Mouret, Coralie; Hautier, Louis

2014-01-01

365

Mode of colony foundation influences the primary sex ratio in ants.  

PubMed

In ants, young queens can found new colonies independently (without the help of workers) or dependently (with the help of workers). It has been suggested that differences in the mode of colony founding strongly influence queen survival and colony development. This is because independent queens are constrained to produce a worker force rapidly, before they deplete their body reserves and to resist the intense intercolony competition during the founding stage. By contrast, queens that found colonies dependently remain with the workers, which probably results in a lower mortality rate and earlier production of reproductive offspring. Consequently, in species that found independently, queens of incipient colonies are expected to produce mostly worker brood by laying a lower fraction of haploid (male) eggs than queens in mature colonies; such a difference would not occur in species founding dependently. We compared the primary sex ratio (proportion of male-determined eggs) laid by queens in incipient and mature colonies of two ant species Lasius nigerLinepithema humile, showing independent and dependent modes of colony founding, respectively. As predicted L. niger queens of incipient colonies laid a lower proportion of haploid eggs than queens from mature colonies. By contrast, queens of L. humile laid a similar proportion of haploid eggs in both incipient and mature colonies. These results provide the first evidence that (1) the primary sex ratio varies according to the mode of colony foundation, and (2) queens can adjust the primary sex ratio according to the life history stage of the colony in ants. Copyright 1999 The Association for the Study of Animal Behaviour. PMID:10049471

Aron; Passera

1999-02-01

366

Blast cell colony assay for umbilical cord blood and adult bone marrow progenitors.  

PubMed

We previously described candidate human blast cell colonies in culture of umbilical cord blood cells. However, their replating efficiencies were low, and we were unable to grow colonies from adult marrow cells. We report here a consistent method of growth and identification of human blast cell colonies that are supported by low serum culture and by delayed addition of medium conditioned by a T lymphoblast cell line, C5MJ. Nonadherent mononuclear cord blood and bone marrow cells were prepared by use of Ficoll-Paque and overnight adherence to plastic. Bone marrow cells were further enriched for progenitors by panning with monoclonal anti-My-10 antibody. Cells were plated in methylcellulose culture containing 2% fetal calf serum and supplemented with bovine serum albumin, lecithin, cholesterol, and transferrin. On day 14 of culture, concentrated C5MJ-conditioned medium was carefully added to each dish. Blast cell colonies consisting of 18 to 100 cells were detected on days 21 to 28. Forty percent to 75% of the blast cell colonies in individual samples yielded secondary colonies upon replating (positive colonies). The replating efficiency of the positive colonies ranged from 3% to 100%. The largest secondary colony contained 7,800 cells. In addition to single-lineage colonies, multilineage colonies revealing two to five lineage combinations were seen. These results suggest that human primitive progenitors are dormant in cell cycle and that they survive in the absence of colony-stimulating factors. Human blast cell colonies may provide a unique population of progenitors for studies of the early process of human hemopoiesis. PMID:3814825

Leary, A G; Ogawa, M

1987-03-01

367

Modern approach to treating mental patients in colonial chosun.  

PubMed

Literature produced by the government and the private sector in the colonial era was reviewed to determine the knowledge of the people of colonial Chosun of mental illness and mental patients and the mental patient management system that they implemented or intended to implement. The results of this study show that the people of Chosun realized the need to sterilize mental patients because they considered mental patients very violent, dangerous and eugenically inferior and they believed that mental patients would eventually impede the prosperity of Chosun. The people of colonial Chosun had learned about the lifelong mental hygiene movement, which had knowledge of mental illness prevention. However, they also recognized that people who developed mental illness despite efforts to prevent such condition needed help from the modern system, especially from modern Western psychiatry. The primary responsibility to attend to mental patients was imposed on their family. The family had to understand the symptoms of mental illness according to the modern medical classification and how to deal with them. When the family could not afford to take care of its mentally ill family member due to the increase in the member's risk behavior such as frenzied-convulsive excitement, paranoia and delusion of jealousy, the family was also responsible for isolating him and connecting him with a mental hospital. The police and social workers were also responsible for observing and monitoring mental patients in their community and for connecting them with a mental hospital. The police made a list of mental patients within their area of jurisdiction and prohibited them from wandering based on the law. It was also considered desirable for mental patients who could not identify their family members to be sent to a mental hospital. Social workers were responsible for managing mental patient sanatoriums, and district commissioners sent to the police mental patients who had no family to look after them or who posed a threat to others, or else commissioned them to the government hospital. Thus, the final responsibility for mental patients was imposed on the modern Western medical team, because the district commissioners sent them to the police and the police sent them to the government mental hospital. Most educated people and government personnel in the colonial era thought modern Western psychiatry circles were responsible for mental patient management, and the Japanese empire enacted mental-healthrelated laws and made efforts to secure funds for the establishment of mental hospitals. As the literature at that time also show the position of the modern Western medical circle, their ambivalent attitude to mental patients must also be clarified to interpret the modern approach to treating mental patients in colonial Chosun. In this context, a research on historical figures in Japanese psychiatry, a study on the specific treatment methods used by the modern Western psychiatric team in the colonial era and their effects, and the extension of the subject period for such researches are suggested. PMID:24005649

Lee, Bang Hyun

2013-08-01

368

Distribution, species abundance, and nesting-site use of Atlantic coast colonies of herons and their allies  

USGS Publications Warehouse

In 1975 and 1976, eight teams of investigators located 262 colonies of nesting herons and their allies along the Atlantic coast from Florida to Maine. Fourteen species were found in Florida, numbers decreasing to seven 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 nestinga dults of each speciesp er colonyi n 1976 were significantlyc orrelatedw ith their respective values for 1975. Abandoned and new colonies appeared to 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.

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

1980-01-01

369

Temporal variation in atmospheric ammonia concentrations above seabird colonies  

NASA Astrophysics Data System (ADS)

Recent studies have shown that seabirds are an important source of ammonia (NH 3) emissions in remote coastal ecosystems. Nesting behaviour, which varies between seabird species, is likely to be a major factor in determining the proportion of excreted nitrogen (N) volatilised to the atmosphere as NH 3. A long-term NH 3 monitoring programme was implemented at a Scottish seabird colony with a range of species and associated nesting behaviours. The average monthly NH 3 concentration was measured at 12 locations over a 14-month period, to infer spatial (i.e. species-specific) and temporal (seasonal) changes in NH 3 emissions from different seabird species. An emissions model of seabird NH 3, based on species-specific bioenergetics and behaviour, was applied to produce spatial estimates for input to a dispersion model. Atmospheric NH 3 concentrations demonstrated spatial variability as a result of differing local populations of breeding seabirds, with the highest concentrations measured above cliff nesting species such as Common guillemot Uria aalge, Razorbill Alca torda and Black-legged kittiwake Rissa tridactyla. NH 3 concentrations above a colony of burrow nesting Atlantic puffin Fratercula arctica were low, considering the high number of birds. Emission of NH 3 from excreted N exhibits a time lag of approximately a month. It is likely that all excreted N is lost from the colony by volatilisation as NH 3 or surface run-off between breeding seasons. Modelled NH 3 emissions and concentrations correlated with measured concentrations, but were much higher, reflecting uncertainties in the local turbulent characteristics. The results allow multi-species seabird population data to be used for the calculation of regional and global NH 3 emission inventories, whilst improving understanding of N budgets of remote coastal ecosystems.

Blackall, T. D.; Wilson, L. J.; Bull, J.; Theobald, M. R.; Bacon, P. J.; Hamer, K. C.; Wanless, S.; Sutton, M. A.

370

Criminal sittings – rape in the colony, New Zealand, 1862.  

PubMed

In 1862 His Honor, Justice Johnston, issued his instructions to the jury of the New Zealand Supreme Court for two simultaneous rape trials – the alleged rape of a European woman by two M?ori men, and an alleged “assault with intent to commit a rape” of a M?ori woman by a European man. This article argues that those instructions should be read within an historiographical critique of British colonial expansion, print capitalism and violence. Drawing on feminist postcolonial theorizing the question posed here, is, “What is the historical, ideological context for a newspaper reporting of the possible rape of a M?ori woman in 1862? PMID:22059253

Erai, Michelle

2011-01-01

371

One's Colonies: a virtual reality environment of oriental residences  

NASA Astrophysics Data System (ADS)

This paper is a statement about my virtual reality environment project, One's Colonies, and a description of the creative process of the project. I was inspired by the buildings in my hometown-Taiwan, which is really different from the architectural style in the United States. By analyzing the unique style of dwellings in Taiwan, I want to demonstrate how the difference between geography, weather and culture change the appearance of the living space. Through this project I want to express the relationship between architectural style and cultural difference, and how the emotional condition or characteristics of the residents are affected by their residencies.

Chi, Catherine

372

Confocal Raman microspectral imaging (CRMI) of murine stem cell colonies.  

PubMed

Confocal Raman micro-spectral imaging (CRMI) is a relatively novel technique for the construction of label-free images of biological entities, such as cells or tissue sections. This method utilizes thousands of spatially resolved Raman spectra, and sophisticated image analysis algorithms, to construct images which are based strictly on the inherent biochemical abundance contrast afforded by Raman microscopy. Here, we apply this methodology to monitor the very early communication processes that occur in a growing stem cell colony, yielding information on biochemical composition during development processes of the early stages of embryogenesis. PMID:20944846

Zuser, Evgenia; Chernenko, Tatyana; Newmark, Judy; Miljkovi?, Miloš; Diem, Max

2010-12-01

373

Design of broadband omnidirectional antireflection coatings using ant colony algorithm.  

PubMed

Optimization method which is based on the ant colony algorithm (ACA) is described to optimize antireflection (AR) coating system with broadband omnidirectional characteristics for silicon solar cells incorporated with the solar spectrum (AM1.5 radiation). It's the first time to use ACA method for optimizing the AR coating system. In this paper, for the wavelength range from 400 nm to 1100 nm, the optimized three-layer AR coating system could provide an average reflectance of 2.98% for incident angles from Rave?+ to 80° and 6.56% for incident angles from 0° to 90°. PMID:24978076

Guo, X; Zhou, H Y; Guo, S; Luan, X X; Cui, W K; Ma, Y F; Shi, L

2014-06-30

374

Space colonies and energy supply to the earth  

NASA Technical Reports Server (NTRS)

It is pointed out that a space manufacturing facility may be economically more effective than alternative industries on the earth for the construction of products which are to be used in geosynchronous or higher orbits. The suggestion is made to construct solar power stations at a space colony and relocate them in geosynchronous orbit to supply energy to the earth. Attention is given to energy problems and approaches for solving them, taking into account environmental effects and economic factors. Economic aspects of space manufacturing are discussed in some detail.

Oneill, G. K.

1975-01-01

375

Aerial estimation of the size of gull breeding colonies  

USGS Publications Warehouse

Counts on photographs and visual estimates of the numbers of territorial gulls are usually reliable indicators of the number of gull nests, but single visual estimates are not adequate to measure the number of nests in individual colonies. To properly interpret gull counts requires that several islands with known numbers of nests be photographed to establish the ratio of gulls to nests applicable for a given local census. Visual estimates are adequate to determine total breeding gull numbers by regions. Neither visual estimates nor photography will reliably detect annual changes of less than about 2.5 percent.

Kadlec, J.A.; Drury, W.H.

1968-01-01

376

Multi-Megawatt Gas Turbine Power Systems for Lunar Colonies  

NASA Technical Reports Server (NTRS)

A concept for development of second generation 10 MWe prototype lunar power plant utilizing a gas cooled fission reactor supplying heated helium working fluid to two parallel 5 MWe closed cycle gas turbines is presented. Such a power system is expected to supply the energy needs for an initial lunar colony with a crew of up to 50 persons engaged in mining and manufacturing activities. System performance and mass details were generated by an author developed code (BRMAPS). The proposed pilot power plant can be a model for future plants of the same capacity that could be tied to an evolutionary lunar power grid.

Juhasz, Albert J.

2006-01-01

377

Improved Robustness through Population Variance in Ant Colony Optimization  

NASA Astrophysics Data System (ADS)

Ant Colony Optimization algorithms are population-based Stochastic Local Search algorithms that mimic the behavior of ants, simulating pheromone trails to search for solutions to combinatorial optimization problems. This paper introduces Population Variance, a novel approach to ACO algorithms that allows parameters to vary across the population over time, leading to solution construction differences that are not strictly stochastic. The increased exploration appears to help the search escape from local optima, significantly improving the robustness of the algorithm with respect to suboptimal parameter settings.

Matthews, David C.; Sutton, Andrew M.; Hains, Doug; Whitley, L. Darrell

378

Scaling of Traction Forces with the Size of Cohesive Cell Colonies  

PubMed Central

To understand how the mechanical properties of tissues emerge from interactions of multiple cells, we measure traction stresses of cohesive colonies of 1–27 cells adherent to soft substrates. We find that traction stresses are generally localized at the periphery of the colony and the total traction force scales with the colony radius. For large colony sizes, the scaling appears to approach linear, suggesting the emergence of an apparent surface tension of the order of 10?3 N/m. A simple model of the cell colony as a contractile elastic medium coupled to the substrate captures the spatial distribution of traction forces and the scaling of traction forces with the colony size.

Mertz, Aaron F.; Banerjee, Shiladitya; Che, Yonglu; German, Guy K.; Xu, Ye; Hyland, Callen; Marchetti, M. Cristina; Horsley, Valerie; Dufresne, Eric R.

2014-01-01

379

Paenibacillus dendritiformis Bacterial Colony Growth Depends on Surfactant but Not on Bacterial Motion? †  

PubMed Central

Most research on growing bacterial colonies on agar plates has concerned the effect of genetic or morphotype variation. Some studies have indicated that there is a correlation between microscopic bacterial motion and macroscopic colonial expansion, especially for swarming strains, but no measurements have been obtained for a single strain to relate the microscopic scale to the macroscopic scale. We examined here a single strain (Paenibacillus dendritiformis type T; tip splitting) to determine both the macroscopic growth of colonies and the microscopic bacterial motion within the colonies. Our multiscale measurements for a variety of growth conditions revealed that motion on the microscopic scale and colonial growth are largely independent. Instead, the growth of the colony is strongly affected by the availability of a surfactant that reduces surface tension.

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

2009-01-01

380

Lower disease infections in honeybee (Apis mellifera) colonies headed by polyandrous vs monandrous queens  

NASA Astrophysics Data System (ADS)

We studied the relationship between genetic diversity and disease susceptibility in honeybee colonies living under natural conditions. To do so, we created colonies in which each queen was artificially inseminated with sperm from either one or ten drones. Of the 20 colonies studied, 80% showed at least one brood disease. We found strong differences between the two types of colonies in the infection intensity of chalkbrood and in the total intensity of all brood diseases (chalkbrood, sacbrood, American foulbrood, and European foulbrood) with both variables lower for the colonies with higher genetic diversity. Our findings demonstrate that disease can be an important factor in the ecology of honeybee colonies and they provide strong support for the disease hypothesis for the evolution of polyandry by social insect queens.

Tarpy, David R.; Seeley, Thomas D.

2006-04-01

381

An improved ant colony algorithm with diversified solutions based on the immune strategy  

PubMed Central

Background Ant colony algorithm has emerged recently as a new meta-heuristic method, which is inspired from the behaviours of real ants for solving NP-hard problems. However, the classical ant colony algorithm also has its defects of stagnation and premature. This paper aims at remedying these problems. Results In this paper, we propose an adaptive ant colony algorithm that simulates the behaviour of biological immune system. The solutions of the problem are much more diversified than traditional ant colony algorithms. Conclusion The proposed method for improving the performance of traditional ant colony algorithm takes into account the polarization of the colonies, and adaptively adjusts the distribution of the solutions obtained by the ants. This makes the solutions more diverse so as to avoid the stagnation and premature phenomena.

Qin, Ling; Pan, Yi; Chen, Ling; Chen, Yixin

2006-01-01

382

Flo11p, drug efflux pumps, and the extracellular matrix cooperate to form biofilm yeast colonies.  

PubMed

Much like other microorganisms, wild yeasts preferentially form surface-associated communities, such as biofilms and colonies, that are well protected against hostile environments and, when growing as pathogens, against the host immune system. However, the molecular mechanisms underlying the spatiotemporal development and environmental resistance of biofilms and colonies remain largely unknown. In this paper, we show that a biofilm yeast colony is a finely tuned, complex multicellular organism in which specialized cells jointly execute multiple protection strategies. These include a Pdr1p-regulated mechanism whereby multidrug resistance transporters Pdr5p and Snq2p expel external compounds solely within the surface cell layers as well as developmentally regulated production by internal cells of a selectively permeable extracellular matrix. The two mechanisms act in concert during colony development, allowing growth of new cell generations in a well-protected internal cavity of the colony. Colony architecture is strengthened by intercellular fiber connections. PMID:21875945

Váchová, Libuse; Stovícek, Vratislav; Hlavácek, Otakar; Chernyavskiy, Oleksandr; St?pánek, Lud?k; Kubínová, Lucie; Palková, Zdena

2011-09-01

383

Opinions from the Front Lines of Cat Colony Management Conflict  

PubMed Central

Outdoor cats represent a global threat to terrestrial vertebrate conservation, but management has been rife with conflict due to differences in views of the problem and appropriate responses to it. To evaluate these differences we conducted a survey of opinions about outdoor cats and their management with two contrasting stakeholder groups, cat colony caretakers (CCCs) and bird conservation professionals (BCPs) across the United States. Group opinions were polarized, for both normative statements (CCCs supported treating feral cats as protected wildlife and using trap neuter and release [TNR] and BCPs supported treating feral cats as pests and using euthanasia) and empirical statements. Opinions also were related to gender, age, and education, with females and older respondents being less likely than their counterparts to support treating feral cats as pests, and females being less likely than males to support euthanasia. Most CCCs held false beliefs about the impacts of feral cats on wildlife and the impacts of TNR (e.g., 9% believed feral cats harmed bird populations, 70% believed TNR eliminates cat colonies, and 18% disagreed with the statement that feral cats filled the role of native predators). Only 6% of CCCs believed feral cats carried diseases. To the extent the beliefs held by CCCs are rooted in lack of knowledge and mistrust, rather than denial of directly observable phenomenon, the conservation community can manage these conflicts more productively by bringing CCCs into the process of defining data collection methods, defining study/management locations, and identifying common goals related to caring for animals.

Peterson, M. Nils; Hartis, Brett; Rodriguez, Shari; Green, Matthew; Lepczyk, Christopher A.

2012-01-01

384

Lymphoma outbreak in a GASH:Sal hamster colony.  

PubMed

We have detected a high incidence of lymphomas in a colony of GASH:Sal Syrian golden hamsters (Mesocricetus auratus). This strain is characterised by its ability to present convulsive crises of audiogenic origin. Almost 16 % (90 males and 60 females) of the 975 animals were affected during a 5-year period by the development of a progressing lymphoid tumour and exhibited similar clinical profiles characterised by lethargy, anorexia, evident abdominal distension, and a rapid disease progression resulting in mortality within 1 to 2 weeks. A TaqMan® probe-based real-time PCR analysis of genomic DNA from different tissue samples of the affected animals revealed the presence of a DNA sequence encoding the hamster polyomavirus (HaPyV) VP1 capsid protein. Additionally, immunohistochemical analysis using HaPyV-VP1-specific monoclonal antibodies confirmed the presence of viral proteins in all hamster tumour tissues analysed within the colony. An indirect ELISA and western blot analysis confirmed the presence of antibodies against the VP1 capsid protein in sera, not only from affected and non-affected GASH:Sal hamsters but also from control hamsters from the same breeding area. The HaPyV genome that accumulated in tumour tissues typically contained deletions affecting the noncoding regulatory region and adjacent sequences coding for the N-terminal part of the capsid protein VP2. PMID:23719671

Muñoz, Luis J; Ludeña, Dolores; Gedvilaite, Alma; Zvirbliene, Aurelija; Jandrig, Burkhard; Voronkova, Tatyana; Ulrich, Rainer G; López, Dolores E

2013-11-01

385

Modeling the role of water in Bacillus subtilis colonies  

NASA Astrophysics Data System (ADS)

We propose a simple cellular automaton model for the description of the evolution of a colony of Bacillus subtilis. The originality of our model lies in the fact that the bacteria can move in a pool of liquid. We assume that each migrating bacterium is surrounded by an individual pool, and the overlap of the latter gives rise to a collective pool with a higher water level. The bacteria migrate collectively when the level of water is high enough. When the bacteria are far enough from each other, the level of water becomes locally too low to allow migration, and the bacteria switch to a proliferating state. The proliferation-to-migration switch is triggered by high levels of a substance produced by proliferating bacteria. We show that it is possible to reproduce in a fairly satisfactory way the various forms that make up the experimentally observed morphological diagram of B. subtilis. We propose a phenomenological relation between the size of the water pool used in our model and the agar concentration of the substrate on which the bacteria migrate. We also compare experimental results from cutting the central part of the colony with the results of our simulations.

Mezanges, X.; Regeard, C.; Gerin, C.; Deroulers, C.; Grammaticos, B.; Badoual, M.

2012-04-01

386

Within-colony migration of symbionts during bleaching of octocorals.  

PubMed

Octocorals compose a major part of cnidarian diversity. As with other symbiont-containing cnidarians, octocorals are susceptible to a stress response and subsequent "bleaching," which typically involves the loss of photosynthetic dinoflagellate symbionts. Studies of bleaching often focus on hexacorals, including sea anemones and scleractinians. The extent to which these results can be generalized to octocorals remains unclear. Bleaching was examined using two representative species of the Holaxonia-Alcyoniina clade of alcyonacean octocorals, Phenganax parrini and Sarcothelia sp. Remarkably, colonies of both species showed the same pattern in response to perturbation: symbionts in the polyps detach or die, leaving the polyps entirely bleached, yet at the same time large numbers of symbionts accumulate in the stolons. These symbionts are contained in host cells, many of which appear to attach to the stolon tissue. A comparison of living and fixed specimens suggests that these cells are loosely bound to, but not actually in, the stolonal tissue. Since gastrovascular fluid in the stolons is driven by cilia, these accumulating cells may lower fluid velocities. The accumulation of symbionts in the stolons during perturbation may have considerable relevance to how octocoral colonies recover from bleaching. PMID:23111136

Parrin, Austin P; Harmata, Katherine L; Netherton, Sarah E; Yaeger, Mark A; Bross, Lori S; Blackstone, Neil W

2012-10-01

387

One Giant Leap: How Insects Achieved Altruism and Colonial Life  

NSDL National Science Digital Library

This peer reviewed article from the January 2008 issue of BioScience examines the origin of altruism leading to eusociality in Hymenoptera. The advanced colonial state of eusociality has evolved in insects as a defense of nest sites within foraging distance of persistent food sources. In the Hymenoptera, the final step in the approach to eusociality is through a suite of preadaptations comprising simultaneous provisioning, fidelity to the nest, and a preexisting propensity toward dominance behavior and the selection of tasks according to opportunity. The only genetic change needed to cross the threshold to the eusocial grade is the foundress's possession of an allele that holds the foundress and her offspring to the nest. The preadaptations provide the phenotypic flexibility required for eusociality, as well as the key emergent traits arising from interactions of the group members. Group (colony-level) selection then immediately acts on both of these traits. The rarity of the origin of eusociality is evidently due to the rarity of the combination of progressive provisioning with environments of the kind that give an edge to group selection over individual direct selection, causing offspring to stay at the natal nest rather than disperse. Several lines of evidence, examined here, suggest that collateral kin selection does not play a significant role.

Edward O. Wilson (Harvard University;)

2008-01-01

388

Queen replacement in orphaned colonies of the fire ant, Solenopsis invicta  

Microsoft Academic Search

1.When field colonies of Solenopsis invicta Buren were orphaned by removing the functioning queen, re-collection 8–10 weeks later showed that 61% had replacement queens that were physogastric and attractive to workers. The weight of the original colony queens increases with the colony mound volume. The weight of replacement queens is inversely related to the number of such queens in the

Walter R. Tschinkel; Dennis F. Howard

1978-01-01

389

Granulocyte Colony-Stimulating Factor Enhances Interleukin 3Dependent Proliferation of Multipotential Hemopoietic Progenitors  

Microsoft Academic Search

In cultures of spleen cells from normal mice, recombinant human granulocyte colony-stimulating factor (G-CSF) supported the formation of multipotential blast cell colonies. Serial replating of the blast cell colonies in the presence of G-CSF, however, failed to demonstrate any direct effect of G-CSF on murine multipotential progenitors. We therefore examined the effects of G-CSF in combination with murine interleukin 3

Kenji Ikebuchi; Steven C. Clark; James N. Ihle; Lawrence M. Souza; Makio Ogawa

1988-01-01

390

Regulation of pollen foraging in honeybee colonies: effects of young brood, stored pollen, and empty space  

Microsoft Academic Search

Pollen storage in a colony of Apis mellifera is actively regulated by increasing and decreasing pollen foraging according to the “colony's needs.” It has been shown that\\u000a nectar foragers indirectly gather information about the nectar supply of the colony from nestmates without estimating the\\u000a amount of honey actually stored in the combs. Very little is known about how the actual

Claudia Dreller; Robert E. Page Jr.; M. Kim Fondrk

1999-01-01

391

Breeding dispersal patterns within a large Sand Martin ( Riparia riparia ) colony  

Microsoft Academic Search

Colonial birds when returning to breed to a previous location can face different settling options regarding their position\\u000a in the colony. The decision could be influenced by information gained from the conspecifics’ performance, known as habitat\\u000a copying. Colonial Sand Martins (Riparia riparia) cannot use evident physical cues when returning to breeding sites, as their nesting substrate is usually renewing completely.

Zoltán D. Szabó; Tibor Szép

2010-01-01

392

Some alternatives in the sociology of space colonization: The kibbutz as a space colony  

NASA Astrophysics Data System (ADS)

This paper critiques the scanty sociological examination on future space colonies. It suggests that the sociology of space colonies has not been examined with due attention to the relationship between the physical problems of surviving in space and the social form of the colony. The Israeli kibbutz form is examined as one example of a viable and logical alternative form of settlement for space colonization.

Ashkenazi, Michael

393

The relationship between serum interferon and an inhibitor of mouse haemopoietic colonies in vitro  

PubMed Central

When mice are inoculated with Poly I—Poly C or influenza virus an inhibitor of haemopoietic colony forming cells appears in the serum. The colony inhibiting activity of whole serum is shown to be directly proportional to the interferon titre. Interferon and colony inhibitor are also shown to have the same properties with regard to molecular size and sensitivity to heat, pH and trypsin.

McNeill, T. A.; Fleming, W. A.

1971-01-01

394

Division of labour and colony efficiency in social insects: effects of interactions between genetic architecture, colony kin structure and rate of perturbations  

PubMed Central

The efficiency of social insect colonies critically depends on their ability to efficiently allocate workers to the various tasks which need to be performed. While numerous models have investigated the mechanisms allowing an efficient colony response to external changes in the environment and internal perturbations, little attention has been devoted to the genetic architecture underlying task specialization. We used artificial evolution to compare the performances of three simple genetic architectures underlying within-colony variation in response thresholds of workers to five tasks. In the ‘deterministic mapping’ system, the thresholds of individuals for each of the five tasks is strictly genetically determined. In the second genetic architecture (‘probabilistic mapping’), the genes only influence the probability of engaging in one of the tasks. Finally, in the ‘dynamic mapping’ system, the propensity of workers to engage in one of the five tasks depends not only on their own genotype, but also on the behavioural phenotypes of other colony members. We found that the deterministic mapping system performed well only when colonies consisted of unrelated individuals and were not subjected to perturbations in task allocation. The probabilistic mapping system performed well for colonies of related and unrelated individuals when there were no perturbations. Finally, the dynamic mapping system performed well under all conditions and was much more efficient than the two other mapping systems when there were perturbations. Overall, our simulations reveal that the type of mapping between genotype and individual behaviour greatly influences the dynamics of task specialization and colony productivity. Our simulations also reveal complex interactions between the mode of mapping, level of within-colony relatedness and risk of colony perturbations.

Waibel, Markus; Floreano, Dario; Magnenat, Stephane; Keller, Laurent

2006-01-01

395

Colony-live —a high-throughput method for measuring microbial colony growth kinetics— reveals diverse growth effects of gene knockouts in Escherichia coli  

PubMed Central

Background Precise quantitative growth measurements and detection of small growth changes in high-throughput manner is essential for fundamental studies of bacterial cell. However, an inherent tradeoff for measurement quality in high-throughput methods sacrifices some measurement quality. A key challenge has been how to enhance measurement quality without sacrificing throughput. Results We developed a new high-throughput measurement system, termed Colony-live. Here we show that Colony-live provides accurate measurement of three growth values (lag time of growth (LTG), maximum growth rate (MGR), and saturation point growth (SPG)) by visualizing colony growth over time. By using a new normalization method for colony growth, Colony-live gives more precise and accurate growth values than the conventional method. We demonstrated the utility of Colony-live by measuring growth values for the entire Keio collection of Escherichia coli single-gene knockout mutants. By using Colony-live, we were able to identify subtle growth defects of single-gene knockout mutants that were undetectable by the conventional method quantified by fixed time-point camera imaging. Further, Colony-live can reveal genes that influence the length of the lag-phase and the saturation point of growth. Conclusions Measurement quality is critical to achieving the resolution required to identify unique phenotypes among a diverse range of phenotypes. Sharing high-quality genome-wide datasets should benefit many researchers who are interested in specific gene functions or the architecture of cellular systems. Our Colony-live system provides a new powerful tool to accelerate accumulation of knowledge of microbial growth phenotypes.

2014-01-01

396

Censusing wading bird colonies: An update on the 'flight-line' count method  

USGS Publications Warehouse

1. Thirteen mixed-species heronries (10 in Florida, two in Virginia, one in North Carolina) were studied in 1980 as part of a project begun in 1979 aimed at evaluating the 'flight-line' census method..2. Standardized counts of Snowy and Cattle Egrets, Louisiana and Little Blue Herons flying to and from the nesting colony were made for three hr periods, followed by a nest count of the colony. 3.Significant differences were found in the flight rates (number of birds per nest x hour) of the four species at the Chincoteague colony. However, when Cattle Egrets and Louisiana Herons were compared at all 13 colonies, their respective flight rates were in opposite rank to those at Chincoteague. Colony differences, then, may mask species differences. 4. A linear regression model showed a strong fit (R2=0.92) between the hourly flight number (3 hr means) and the nest number, but point estimates (single colony) had very large confidence limits. A given colony might be over-or underestimated by a factor of 2, using the regression equation as a predictive model. 5. A more appropriate application of the method would be to determine regionwide (e.g., state), rather than colony-specific, population estimates. 'Total' estimates for all (n= 13) colonies were within 10% of the actual nest number.

Erwin, R.M.

1981-01-01

397

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

PubMed

Organisation in eusocial insect colonies emerges from the decisions and actions of its individual members. In turn, these decisions and actions are influenced by the individual's behaviour (or temperament). Although there is variation in the behaviour of individuals within a colony, we know surprisingly little about how (or indeed if) the types of behaviour present in a colony change over time. Here, for the first time, we assessed potential changes in the behavioural type of foragers during colony development. Using an ecologically relevant foraging task, we measured the decision speed and learning ability of bumble bees (Bombus terrestris) at different stages of colony development. We determined whether individuals that forage early in the colony life cycle (the queen and early emerging workers) behaved differently from workers that emerge and forage at the end of colony development. Whilst we found no overall change in the foraging behaviour of workers with colony development, there were strong differences in foraging behaviour between queens and their workers. Queens appeared to forage more cautiously than their workers and were also quicker to learn. These behaviours could allow queens to maximise their nectar collecting efficiency whilst avoiding predation. Because the foundress queen is crucial to the survival and success of a bumble bee colony, more efficient foraging behaviour in queens may have strong adaptive value. PMID:24599144

Evans, Lisa J; Raine, Nigel E

2014-01-01

398

New method for discovery of starch phenotypes in growing microalgal colonies.  

PubMed

To identify algal strains with altered starch metabolism from a large pool of candidates of growing algal colonies, we have developed a novel, high-throughput screening tool by combining gaseous bleaching of replica transferred colonies and subsequent iodine staining to visualize starch. Screening of healthy growing colonies of microalgae has not been possible previously because high levels of chlorophyll make the detection of starch with an iodine stain impossible. We demonstrated that chlorine dioxide (ClO(2)) removes essentially all chlorophyll from the colonies and enables high-throughput screening of, for example, a population of mutagenized cells or a culture collection isolated in a bioprospecting project. PMID:23026776

Black, Stuart K; Smolinski, Sharon L; Feehan, Corinne; Pienkos, Philip T; Jarvis, Eric E; Laurens, Lieve M L

2013-01-15

399

Cooperatively Generated Stresslet Flows Supply Fresh Fluid to Multicellular Choanoflagellate Colonies  

NASA Astrophysics Data System (ADS)

The flagellated protozoan Salpingoeca rosetta is one of the closest relatives of multicellular animals. Unicellular S. rosetta can be induced to form multicellular colonies, but colonies swim more slowly than individual cells so the advantages conferred by colony formation are uncertain. Here we use theoretical models to show that hydrodynamic cooperation between cells can increase the fluid supply to the colony, an important predictor of feeding rate. Our results suggest that hydrodynamic benefits may have been an important selective factor in the evolution of early multicellular animals.

Roper, Marcus; Dayel, Mark J.; Pepper, Rachel E.; Koehl, M. A. R.

2013-05-01

400

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

PubMed

In colony collapse disorder (CCD), honey bee colonies inexplicably lose their workers. CCD has resulted in a loss of 50 to 90% of colonies in beekeeping operations across the United States. The observation that irradiated combs from affected colonies can be repopulated with naive bees suggests that infection may contribute to CCD. We used an unbiased metagenomic approach to survey microflora in CCD hives, normal hives, and imported royal jelly. Candidate pathogens were screened for significance of association with CCD by the examination of samples collected from several sites over a period of 3 years. One organism, Israeli acute paralysis virus of bees, was strongly correlated with CCD. PMID:17823314

Cox-Foster, Diana L; Conlan, Sean; Holmes, Edward C; Palacios, Gustavo; Evans, Jay D; Moran, Nancy A; Quan, Phenix-Lan; Briese, Thomas; Hornig, Mady; Geiser, David M; Martinson, Vince; vanEngelsdorp, Dennis; Kalkstein, Abby L; Drysdale, Andrew; Hui, Jeffrey; Zhai, Junhui; Cui, Liwang; Hutchison, Stephen K; Simons, Jan Fredrik; Egholm, Michael; Pettis, Jeffery S; Lipkin, W Ian

2007-10-12

401

Breeding ecology of Caspian terns at colonies on the Columbia Plateau  

USGS Publications Warehouse

We investigated the breeding ecology and diet of Caspian terns on the Columbia Plateau in southeastern Washington and northeastern Oregon. We examined trends in colony size and area during 1996-2001, and estimated number of breeding pairs, nesting density, fledging success, and diet composition at selected colony sites in 2000 and 2001. We found six tern colonies totaling ???1,000 breeding pairs, ranging in size from < 50 to nearly 700 pairs. Predation by mink caused complete abandonment of one of these colonies in 2000 and 2001. The relocation of ???9,000 Caspian tern breeding pairs from Rice Island to East Sand Island in the Columbia River estuary did not result in an obvious increase in the number of tern breeding pairs on the Columbia Plateau during the study period. The majority of Caspian tern prey items at colonies on the mid-Columbia River consisted of juvenile salmonids. At a colony in Potholes Reservoir, Washington, Caspian terns commuted over 100 km round-trip to the Columbia River to forage on juvenile salmonids, suggesting that locally abundant food may be limiting. High nesting densities at other mid-Columbia River colonies suggest that availability of breeding habitat may limit colony size. The small size of Caspian tern colonies on the Columbia Plateau, and possible constraints on availability of suitable nesting habitat within the study area, suggest that the level of predation on ESA-listed juvenile salmonids in this region will likely remain well below that currently observed in the Columbia River estuary.

Antolos, M.; Roby, D. D.; Collis, K.

2005-01-01

402

Clonal Expression of the Tn Antigen in Erythroid and Granulocyte Colonies and Its Application to Determination of the Clonality of the Human Megakaryocyte Colony Assay  

PubMed Central

To evaluate whether exposure of Tn determinants at the surface of human erythrocytes, platelets, and granulocytes could arise from a somatic mutation in a hemopoietic stem cell, burst-forming unit erythroid (BFU-E) colonies, colony-forming unit granulocyte-macrophage (CFU-GM), and colony-forming unit-eosinophil (CFU-Eo) were grown from a blood group O patient with a typical Tn syndrome displaying two distinct populations (Tn+ and Tn-) of platelets, granulocytes, and erythrocytes. A large number of colonies was observed. Individual colonies were studied with a fluorescent conjugate of Helix pomatia agglutinin (HPA). A sizeable fraction of each of the erythroid and granulocytic colonies appeared to consist exclusively of either HPA-positive or HPA-negative cells, thereby demonstrating the clonal origin of those exhibiting the Tn marker. Similar results were obtained from a second patient. These findings establish that the HPA labeling of Tn cells is an accurate marker permitting assessment of the clonality of the human megakaryocyte (MK) colony assay. For the study of MK cultures a double-staining procedure using the HPA lectin and a monoclonal antiplatelet antibody (J-15) was applied in situ to identify all MK constituting a colony. Our results, obtained in studies of 133 MK colonies, provide definitive evidence that the human MK colony assay is clonal because all MK colonies were exclusively composed of Tn+ and Tn- MK. Furthermore, the distribution of MK within a single colony was shown to be seminormal with a mean at 6 MK, isolated MK typically being absent in culture. Comparison of the proportion of mature Tn+ cells in blood with their respective Tn+ progenitors has also shown that no proliferative advantage occurs after the commitment; because Tn polyagglutinability is an acquired disorder, then the expansion of the Tn+ clone must occur either during the proliferative stage of the pluripotent stem cell or during the commitment itself. This study therefore affords evidence that a blood group antigen plays a role in the differentiation of a pluripotent stem cell. Images

Vainchenker, William; Testa, Ugo; Deschamps, Jeanne Francoise; Henri, Annie; Titeux, Monique; Breton-Gorius, Janine; Rochant, Henri; Lee, Douglas; Cartron, Jean-Pierre

1982-01-01

403

The relevance of the Mediterranean Region to colonial waterbird conservation  

USGS Publications Warehouse

The Mediterranean Sea is the largest partially enclosed sea in the world and provides habitat to more than 100 species of waterbirds from the Palearctic-North African-Middle Eastern regions. Even though the Mediterranean suffers from pollution, has little tidal influence, and is oligotrophic, more than half of the western Palearctic populations of numerous waterfowl species winter in the region. Thirty-three species of colonial waterbirds breed along the 46,000 km Mediterranean coastline with nine species considered threatened or endangered, mostly because of wetland loss and degradation. The long history of human activity and scientific investigations in the region has taught some valuable lessons. In the area of colonial waterbird biology and conservation, we have learned important lessons about the value of long-term monitoring and research on selected populations. From marking studies of Greater Flamingos (Phoenicopterus ruber roseus) and Little Egrets (Egretta garzetta) results have been used to derive useful information about metapopulation dynamics. Involvement of both African and European biologists allowed year-round Studies of these species that yielded valuable spin-offs for training in avian and wetland conservation. We have also learned the value of man-made wetlands as feeding and nesting sites for some colonial waterbirds. Careful evaluations of the habitat quality of different types of wetlands are required, as in contaminant levels such as lead shot and pesticides. Wetland conservationists have also learned from some instructive mistakes. Dam construction and agricultural incentive programs sponsored by the European Community, the World Bank, and others from the past have largely ignored impacts on wetlands and wildlife. In some areas, economic ventures such as aquaculture operations and salt mining have not involved waterbird habitat needs in their planning. Research and conservation needs include: (1) establishing regional monitoring programs and data banks for seabirds, wading birds, ducks, and geese; (2) implementing a wetland inventory for many Countries with little quantitative data on wetlands; (3) improving habitat quality assessments; (4) improving relationships with industry, the private citizenry, and government officials to further an appreciation for the value of wetlands and waterbirds; (5) enhancing training efforts, especially in underdeveloped Countries; (6) evaluating the effects of hunting and other disturbances to nesting and feeding waterbirds in different regions; (7) setting up 'sister-reserve' (twinned) sites in Europe and Africa to foster international linkages and training; and (8) fostering local-regional conservation programs to preserve reed beds, wet woodlots, and other key habitats.

Erwin, R.M.

1996-01-01

404

Does coloniality improve foraging efficiency and nestling provisioning? A field experiment in the wild Zebra Finch.  

PubMed

The foraging benefits of coloniality, whereby colony members exchange information about food location, have been suggested as a primary factor influencing the evolution of coloniality. However, despite its longstanding popularity, this hypothesis has rarely been tested experimentally. Here, we conducted a field experiment in the wild Zebra Finch Taeniopygia guttata to test whether colonial birds are better at finding food than solitary individuals. We manipulated food patch location and directly measured foraging activity of many colonial and solitary parents at those patches using an electronic monitoring system. We provided nesting sites in excess to alleviate nest site competition and manipulated brood size to eliminate the possible correlation between brood size, nesting density, and individual quality (including foraging activity). We found that solitary birds found experimental food patches first, closely followed by colonial birds. Moreover, solitary parents adjusted the amount of food per nestling to experimental brood size, whereas colonial parents did not, although overall, nestlings were fed more per capita in colonial than in solitary nests. In addition, brood size and, to a lesser extent, nesting density negatively affected nestling growth. Therefore, with the effect of provisioning rate, sibling competition, and cost of coloniality combined, nestling mass was not affected by the brood manipulation in solitary nests, whereas nestlings were lighter in enlarged than in reduced broods in colonies. Our resultstherefore suggest that individuals settling in solitary nests were intrinsically better foragers and more optimal parents. While they do not invalidate the possibility of information transfer at colonies, our findings highlight the importance of considering settlement bias in future studies and add to the existing evidence that the effects of nesting density on fitness are both complex and multiple. PMID:23691652

Mariette, Mylene M; Griffith, Simon C

2013-02-01

405

Quantitative colony method for tumorigenic cells transformed by two distinct strains of Friend leukemia virus  

PubMed Central

An in vitro colony method capable of detecting spleen cells malignantly transformed by Friend leukemia virus is described. These colony-forming cells, which form large erythroid colonies (104-105 cells) in methylcellulose, can be detected late after infection with either the anemia-inducing (FV-A) or polycythemia-inducing (FV-P) isolates of Friend virus. Colony formation by these cells is dependent only on fetal calf serum as an exogeneous growth factor. The presence of these colony-forming cells in FV-P-infected spleens could not be detected until at least 3 weeks after virus infection, even though the most rapid increase in spleen weight occurred earlier, between 1 and 2 weeks after infection. Thereafter, the numbers of colony-forming cells increased sharply up to 5 weeks after infection with FV-P, beyond which time the mice generally did not survive. After infection with FV-A, colony-forming cells were detected only at 8-12 weeks and their numbers generally increased thereafter. Permanent cell lines were established from a significant fraction of FV-P and FV-A-induced colonies, and these cell lines could be chemically induced to synthesize hemoglobin. All individual colonies produced complete Friend virus complex. However, virus production appeared to decline in at least some cell lines. Both FV-P- and FV-A-induced colonies contained cells capable of forming spleen colonies in irradiated recipients and subcutaneous tumors in unirradiated mice. Thus, the assay method described here appears to detect a unique class of malignant Friend virus-transformed cells that can be detected only in the advanced stages of Friend virus-induced erythroleukemia. Images

Mager, Dixie L.; Mak, Tak W.; Bernstein, Alan

1981-01-01

406

The Alternative Role of Enterobactin as an Oxidative Stress Protector Allows Escherichia coli Colony Development  

PubMed Central

Numerous bacteria have evolved different iron uptake systems with the ability to make use of their own and heterologous siderophores. However, there is growing evidence attributing alternative roles for siderophores that might explain the potential adaptive advantages of microorganisms having multiple siderophore systems. In this work, we show the requirement of the siderophore enterobactin for Escherichia coli colony development in minimal media. We observed that a strain impaired in enterobactin production (entE mutant) was unable to form colonies on M9 agar medium meanwhile its growth was normal on LB agar medium. Given that, neither iron nor citrate supplementation restored colony growth, the role of enterobactin as an iron uptake-facilitator would not explain its requirement for colony development. The absence of colony development was reverted either by addition of enterobactin, the reducing agent ascorbic acid or by incubating in anaerobic culture conditions with no additives. Then, we associated the enterobactin requirement for colony development with its ability to reduce oxidative stress, which we found to be higher in media where the colony development was impaired (M9) compared with media where the strain was able to form colonies (LB). Since oxyR and soxS mutants (two major stress response regulators) formed colonies in M9 agar medium, we hypothesize that enterobactin could be an important piece in the oxidative stress response repertoire, particularly required in the context of colony formation. In addition, we show that enterobactin has to be hydrolyzed after reaching the cell cytoplasm in order to enable colony development. By favoring iron release, hydrolysis of the enterobactin-iron complex, not only would assure covering iron needs, but would also provide the cell with a molecule with exposed hydroxyl groups (hydrolyzed enterobactin). This molecule would be able to scavenge radicals and therefore reduce oxidative stress.

Peralta, Daiana R.; Pomares, Maria Fernanda; de Cristobal, Ricardo E.; Vincent, Paula A.

2014-01-01

407

Pathological findings in a captive colony of maras (Dolichotis patagonum).  

PubMed

This paper describes the causes of death of 54 maras (Dolichotis patagonum) in a captive colony in Mexico over a period of seven years. There were 35 adults, 11 juveniles, five neonates, two fetuses and one stillbirth--27 males, 21 females and six whose sex was not determined. Trauma was the cause of 25 deaths, and there were eight cases of fatal bacterial infection. Besnoitiosis was the only parasitic disease found frequently (13 cases), and was associated with fatal interstitial pneumonia in three juveniles. Right-sided hypertrophic cardiomyopathy attributed to high altitude was observed in 26 maras, and in three cases death was attributed to acute cardiac dysfunction. Two maras died of disseminated histoplasmosis and two of hyperthermia. Additional causes of death included one case each of uterine torsion, intestinal intussusception, aspiration pneumonia and hydranencephaly. Gastric erosions with luminal haemorrhage were found in 27 of the maras and splenic lymphoid depletion in 20, changes that were attributed to stress. PMID:16731703

Rosas-Rosas, A G; Juan-Sallés, C; Garner, M M

2006-05-27

408

Enlightened publics for public health: assessing disease in colonial Mexico.  

PubMed

In the eighteenth century, a new genre of periodical literature appeared from Mexico City's presses that focused on disseminating scientific and medical knowledge to the colonial public. In part a natural extension of the healing manuals published for laypeople in previous centuries, the journals sought to introduce quantitative methods of environmental study and control and to expand the sphere of those residents who would take responsibility for their health. This article examines the content and format of these journals before turning to the response of urban publics during outbreaks of epidemics, when the broader social participation envisioned by enlightenment men of letters came to fruition through pasquinades and rumors conveying dissent, skepticism, and protest. PMID:23369446

Ramírez, Paul

2013-03-01

409

Ant Colony Optimization With Combining Gaussian Eliminations for Matrix Multiplication.  

PubMed

One of the main unsolved problems in computer algebra is to determine the minimal number of multiplications which is necessary to compute the product of two matrices. For practical value, the small format is of special interest. This leads to a combinatorial optimization problem which is unlikely solved in polynomial time. In this paper, we present a method called combining Gaussian eliminations to reduce the number of variables in this optimization problem and use heuristic ant colony algorithm to solve the problem. The results of experiments on 2 × 2 case show that our algorithm achieves significant performance gains. Extending this algorithm from 2 × 2 case to 3 × 3 case is also discussed. PMID:22835561

Zhou, Yuren; Lai, Xinsheng; Li, Yuanxiang; Dong, Wenyong

2012-07-20

410

Automatic fault tracking based on ant colony algorithms  

NASA Astrophysics Data System (ADS)

The mapping of the fault network is of key importance in reservoir characterization. Interpretation of faults in seismic data is today most commonly a manual task. This is time consuming and difficult to do accurately. Automatic extraction of the fault surfaces would allow user-interaction at a higher level. In this paper, we implemented and tested an automatic fault tracking scheme based on the ant colony algorithm. We applied the proposed method to auto-track the faults on seismic data. Its performance on real seismic data indicates that the proposed method can effectively reduce the noise level and improve the continuity of faults on seismic coherency cube. In order to assess the performance of the auto-tracking for faults, we make a comparison of the results from the auto-tracking with manual interpretations of fault geometry over the same area. The comparison demonstrates that the proposed method detects most faults accurately.

Yan, Zhe; Gu, Hanming; Cai, Chengguo

2013-02-01

411

Automatic fault extraction using a modified ant-colony algorithm  

NASA Astrophysics Data System (ADS)

The basis of automatic fault extraction is seismic attributes, such as the coherence cube which is always used to identify a fault by the minimum value. The biggest challenge in automatic fault extraction is noise, including that of seismic data. However, a fault has a better spatial continuity in certain direction, which makes it quite different from noise. Considering this characteristic, a modified ant-colony algorithm is introduced into automatic fault identification and tracking, where the gradient direction and direction consistency are used as constraints. Numerical model test results show that this method is feasible and effective in automatic fault extraction and noise suppression. The application of field data further illustrates its validity and superiority.

Zhao, Junsheng; Zandong Sun, Sam

2013-04-01

412

The colonial origins of comparative development: An empirical investigation  

Microsoft Academic Search

We exploit differences in European mortality rates to estimate the\\u000d\\u000a\\u0009effect of institutions on economic performance. Europeans adopted\\u000d\\u000a\\u0009very different colonization policies in different colonies, with\\u000d\\u000a\\u0009different associated institutions. In places where Europeans faced\\u000d\\u000a\\u0009high mortality rates, they, could not settle and were more likely\\u000d\\u000a\\u0009to set up extractive institutions. These institutions persisted to\\u000d\\u000a\\u0009the present. Exploiting differences in European

Daron Acemoglu; Simon Johnson; James A. Robinson

2001-01-01

413

A closed life-support system for space colonies  

NASA Technical Reports Server (NTRS)

In 1975, a system design study was performed to examine a completely self-contained system for a permanent colony of 10,000 inhabitants in space. Fundamental to this design was the life support system. Since resupply from earth is prohibitive in transportation costs, it was decided to use a closed system with the initial supply of oxygen coming from processing of lunar ores, and the supply of carbon, nitrogen and hydrogen from earth. The problem of life support was treated starting with the nutritional and metabolic requirements for the human population, creating a food and water chain sufficient to supply these demands, adding the additional requirements for the animal and plant sources in the food chain, feeding back useful waste products, supplying water as required from different sources, and closing the loop by processing organic wastes into CO2. This concept places the burden of the system upon plants for O2 generation and waste processing the CO2 generation.

Johnson, R. D.; Jebens, H. J.; Sweet, H. C.

1977-01-01

414

Ant Colony Optimization for Markowitz Mean-Variance Portfolio Model  

NASA Astrophysics Data System (ADS)

This work presents Ant Colony Optimization (ACO), which was initially developed to be a meta-heuristic for combinatorial optimization, for solving the cardinality constraints Markowitz mean-variance portfolio model (nonlinear mixed quadratic programming problem). To our knowledge, an efficient algorithmic solution for this problem has not been proposed until now. Using heuristic algorithms in this case is imperative. Numerical solutions are obtained for five analyses of weekly price data for the following indices for the period March, 1992 to September, 1997: Hang Seng 31 in Hong Kong, DAX 100 in Germany, FTSE 100 in UK, S&P 100 in USA and Nikkei 225 in Japan. The test results indicate that the ACO is much more robust and effective than Particle swarm optimization (PSO), especially for low-risk investment portfolios.

Deng, Guang-Feng; Lin, Woo-Tsong

415

A Multistrategy Optimization Improved Artificial Bee Colony Algorithm  

PubMed Central

Being prone to the shortcomings of premature and slow convergence rate of artificial bee colony algorithm, an improved algorithm was proposed. Chaotic reverse learning strategies were used to initialize swarm in order to improve the global search ability of the algorithm and keep the diversity of the algorithm; the similarity degree of individuals of the population was used to characterize the diversity of population; population diversity measure was set as an indicator to dynamically and adaptively adjust the nectar position; the premature and local convergence were avoided effectively; dual population search mechanism was introduced to the search stage of algorithm; the parallel search of dual population considerably improved the convergence rate. Through simulation experiments of 10 standard testing functions and compared with other algorithms, the results showed that the improved algorithm had faster convergence rate and the capacity of jumping out of local optimum faster.

Liu, Wen

2014-01-01

416

A multistrategy optimization improved artificial bee colony algorithm.  

PubMed

Being prone to the shortcomings of premature and slow convergence rate of artificial bee colony algorithm, an improved algorithm was proposed. Chaotic reverse learning strategies were used to initialize swarm in order to improve the global search ability of the algorithm and keep the diversity of the algorithm; the similarity degree of individuals of the population was used to characterize the diversity of population; population diversity measure was set as an indicator to dynamically and adaptively adjust the nectar position; the premature and local convergence were avoided effectively; dual population search mechanism was introduced to the search stage of algorithm; the parallel search of dual population considerably improved the convergence rate. Through simulation experiments of 10 standard testing functions and compared with other algorithms, the results showed that the improved algorithm had faster convergence rate and the capacity of jumping out of local optimum faster. PMID:24982924

Liu, Wen

2014-01-01

417

Radiation response of murine erythroid colony-forming units (CFUe)  

SciTech Connect

The response of murine erythroid colony-forming units (CFUe) to 150 kVp X-rays has been investigated. Femoral bone marrow was obtained from LAF1 female mice and the plasma clot culture method was used to assay for CFUe survival. The dose-response data of CFUe receiving single dose irradiations was fitted to the multitarget single hit (MTSH). Survival of CFUe was measured after single dose in vivo irradiations of mice which had and had not been anesthetized. Survival of CFUe was measured after single dose in vitro irradiations of bone marrow suspensions held at 4{degree}C. In addition, survival of CFUe was measured after single dose in vitro irradiations of bone marrow suspensions held at 22{degree}C. The radiosensitivity of 4{degree}C CFUe was not shown to be significantly different from the radiosensitivity of 22{degree}C CFUe.

Berger, S.E.

1987-01-01

418

Automatic image enhancement by artificial bee colony algorithm  

NASA Astrophysics Data System (ADS)

With regard to the improvement of image quality, image enhancement is an important process to assist human with better perception. This paper presents an automatic image enhancement method based on Artificial Bee Colony (ABC) algorithm. In this method, ABC algorithm is applied to find the optimum parameters of a transformation function, which is used in the enhancement by utilizing the local and global information of the image. In order to solve the optimization problem by ABC algorithm, an objective criterion in terms of the entropy and edge information is introduced to measure the image quality to make the enhancement as an automatic process. Several images are utilized in experiments to make a comparison with other enhancement methods, which are genetic algorithm-based and particle swarm optimization algorithm-based image enhancement methods.

Yimit, Adiljan; Hagihara, Yoshihiro; Miyoshi, Tasuku; Hagihara, Yukari

2013-03-01

419

Macrophage colony-stimulating factor suppresses osteoblast formation.  

PubMed

We provide the first evidence that the bone marrow-derived cytokine, macrophage colony-stimulating factor (M-CSF), inhibits the formation of bone-forming osteoblasts. We examined both osteoclast and osteoblast formation in primary rat bone marrow cultures. As expected, M-CSF together with osteoprotegerin ligand (OPGL) markedly accelerated osteoclastogenesis. In contrast, treatment with M-CSF alone yielded no osteoclasts at any time. The most striking and novel observation was that M-CSF with or without OPGL dramatically suppressed osteoblast formation. In separate experiments, estradiol markedly suppressed osteoclast formation in the M-CSF/OPGL-treated cultures independently of osteoblasts. Consistent with this was the expression of estrogen receptor-alpha (ERalpha) and ERbeta mRNA in osteoclast precursors. We therefore conclude that in addition to the well-known action of M-CSF to modulate osteoclastogenesis, this cytokine may also regulate osteoblast formation. PMID:11444846

Gyda, M; Corisdeo, S; Zaidi, M; Troen, B R

2001-07-13

420

Transport of lunar material to the sites of the colonies  

NASA Technical Reports Server (NTRS)

An 'existence proof' is attempted for the feasibility of transport of lunar material to colonies in space. Masses of lunar material are accelerated to lunar escape by a tracked magnetically levitated mass driver; aim precision is to 1 km miss distance at L5 per mm/sec velocity error at the lunar surface. Mass driver design and linear synchronous motor drive design are discussed; laser-sensed checkpoints aid in velocity and directional precision. Moon-L5 trajectories are calculated. The design of the L5 construction station, or 'catcher vehicle,' is described; loads are received by chambers operating in a 'Venus flytrap' mode. Further research studies needed to round out the concept are listed explicitly.

Heppenheimer, T. A.

1977-01-01

421

Improved artificial bee colony algorithm based gravity matching navigation method.  

PubMed

Gravity matching navigation algorithm is one of the key technologies for gravity aided inertial navigation systems. With the development of intelligent algorithms, the powerful search ability of the Artificial Bee Colony (ABC) algorithm makes it possible to be applied to the gravity matching navigation field. However, existing search mechanisms of basic ABC algorithms cannot meet the need for high accuracy in gravity aided navigation. Firstly, proper modifications are proposed to improve the performance of the basic ABC algorithm. Secondly, a new search mechanism is presented in this paper which is based on an improved ABC algorithm using external speed information. At last, modified Hausdorff distance is introduced to screen the possible matching results. Both simulations and ocean experiments verify the feasibility of the method, and results show that the matching rate of the method is high enough to obtain a precise matching position. PMID:25046019

Gao, Wei; Zhao, Bo; Zhou, Guang Tao; Wang, Qiu Ying; Yu, Chun Yang

2014-01-01

422

Colony-Stimulating Factors for Febrile Neutropenia during Cancer Therapy  

PubMed Central

A 55-year-old, previously healthy woman received a diagnosis of diffuse large-B-cell lymphoma after the evaluation of an enlarged left axillary lymph node obtained on biopsy. She had been asymptomatic except for the presence of enlarged axillary lymph nodes, which she had found while bathing. She was referred to an oncologist, who performed a staging evaluation. A complete blood count and test results for liver and renal function and serum lactate dehydrogenase were normal. Positron-emission tomography and computed tomography (PET–CT) identified enlarged lymph nodes with abnormal uptake in the left axilla, mediastinum, and retroperitoneum. Results on bone marrow biopsy were normal. The patient’s oncologist recommends treatment with six cycles of cyclophosphamide, doxorubicin, vincristine, and prednisone with rituximab (CHOP-R) at 21-day intervals. Is the administration of prophylactic granulocyte colony-stimulating factor (G-CSF) with the first cycle of chemotherapy indicated?

Bennett, Charles L.; Djulbegovic, Benjamin; Norris, LeAnn B.; Armitage, James O.

2014-01-01

423

Finite grade pheromone ant colony optimization for image segmentation  

NASA Astrophysics Data System (ADS)

By combining the decision process of ant colony optimization (ACO) with the multistage decision process of image segmentation based on active contour model (ACM), an algorithm called finite grade ACO (FACO) for image segmentation is proposed. This algorithm classifies pheromone into finite grades and updating of the pheromone is achieved by changing the grades and the updated quantity of pheromone is independent from the objective function. The algorithm that provides a new approach to obtain precise contour is proved to converge to the global optimal solutions linearly by means of finite Markov chains. The segmentation experiments with ultrasound heart image show the effectiveness of the algorithm. Comparing the results for segmentation of left ventricle images shows that the ACO for image segmentation is more effective than the GA approach and the new pheromone updating strategy appears good time performance in optimization process.

Yuanjing, F.; Li, Y.; Liangjun, K.

2008-06-01

424

Strong Combination of Ant Colony Optimization with Constraint Programming Optimization  

NASA Astrophysics Data System (ADS)

We introduce an approach which combines ACO (Ant Colony Optimization) and IBM ILOG CP Optimizer for solving COPs (Combinatorial Optimization Problems). The problem is modeled using the CP Optimizer modeling API. Then, it is solved in a generic way by a two-phase algorithm. The first phase aims at creating a hot start for the second: it samples the solution space and applies reinforcement learning techniques as implemented in ACO to create pheromone trails. During the second phase, CP Optimizer performs a complete tree search guided by the pheromone trails previously accumulated. The first experimental results on knapsack, quadratic assignment and maximum independent set problems show that this new algorithm enhances the performance of CP Optimizer alone.

Khichane, Madjid; Albert, Patrick; Solnon, Christine

425

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

Microsoft Academic Search

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

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

1987-01-01

426

Altered Protein Kinase C Activity in Biopsies of Human Colonie Adenomas and Carcinomas1  

Microsoft Academic Search

Protein kinase C (PK-C) seems to be involved in the regulation of growth and differentiation of normal epithelial cells. Colonie adenomas and carcinomas show increased proliferation and decreased differentia tion. We investigated the activity and subcellular distribution of PK-C in biopsies of normal, neoplastic, and malignant colonie epithelium to eval uate alterations in enzyme activity. In the control group (n

R. Kopp; B. Noelke; G. Sauter; F. W. Schildberg; G. Paumgartner; A. Pfeiffer

427

The Power of Social Theory: The Anti-Colonial Discursive Framework.  

ERIC Educational Resources Information Center

Introduces the anti-colonial discourse as a guiding framework for forming alliances and partnerships among anti-oppression activists in academia and the larger society. Asserts that the anti-colonial discourse seeks to reclaim a new independent space strongly connected to other theories, such as Marxist, feminist, and deconstructionist. Describes…

Sefa Dei, George J.; Asgharzadeh, Alireza

2001-01-01

428

Teaching Morality and Religion in Nineteenth-Century Colonial Algeria: Gender and the Civilising Mission  

ERIC Educational Resources Information Center

Historians have long presented France's "civilizing mission" within its colonies in secular terms ignoring women's presence as both actors and subjects. This is particularly true in Algeria where the colonial government's explicitly prohibited proselytism. This article emphasizes women's roles pursuing both secular and religious goals in Algeria.…

Rogers, Rebecca

2011-01-01

429

The Colonial Mentality Scale (CMS) for Filipino Americans: Scale Construction and Psychological Implications  

ERIC Educational Resources Information Center

Colonial mentality, or internalized colonialism, has been discussed by scholars and by Filipino American community members as a significant factor in the experiences of contemporary Filipino Americans, yet this construct has not received empirical attention in psychology. The authors of the current study addressed this gap in the Asian American…

David, E. J. R.; Okazaki, Sumie

2006-01-01

430

An ant colony algorithm Hybridized with Iterated Local Search for the QAP  

Microsoft Academic Search

The quadratic assignment problem (QAP) is considered one of the hardest combinatorial optimization problems. Ant colony algorithm (ACA), inspired by the food-searching behavior of ants, is an evolutionary algorithm and performs well in discrete optimization. In this paper, through an analysis of the constructive procedure of the solution in the ACA, a hybrid ant colony system (ACAILS) with iterated local

Mingping Xia

2009-01-01

431

The Influence of Colonial Ideology on Schoolbooks in the Belgian Congo.  

ERIC Educational Resources Information Center

An analysis of 50 textbooks used in the elementary schools of the former Belgian Congo reveals an overt attempt to propagate colonial ideology. Fundamental themes included the legitimacy of the colonization, denigration of the indigenous culture, and establishment of colonial authority. Three books, however, resisted this indoctrination and one…

Mbandaka, Honore Vinck

1995-01-01

432

Phelps-Stokes in Congo: Transferring Educational Policy Discourse to Govern Metropole and Colony  

ERIC Educational Resources Information Center

This article combines a historical with a social/political anthropological framework to examine the role played by the transfer of educational discourse between the United States-based Phelps-Stokes Fund and the Belgian Ministry of Colonies in the formulation of the colonial education policy of "adapted education" in the 1920s. The author argues…

Seghers, Maud

2004-01-01

433

Studies of bacterial branching growth using reaction–diffusion models for colonial development  

Microsoft Academic Search

Various bacterial strains exhibit colonial branching patterns during growth on poor substrates. These patterns reflect bacterial cooperative self-organization and cybernetic processes of communication, regulation and control employed during colonial development. One method of modeling is the continuous, or coupled reaction–diffusion approach, in which continuous time evolution equations describe the bacterial density and the concentration of the relevant chemical fields. In

Ido Golding; Yonathan Kozlovsky; Inon Cohen; Eshel Ben-Jacob

1998-01-01

434

Resource allocation, brood production and cannibalism during colony founding in the fire ant, Solenopsis invicta  

Microsoft Academic Search

Summary The colony founding characteristics of newly mated fire ant queens from monogyne colonies were studied in the field and in the laboratory under haplo- and pleometrotic conditions. Initial queen weight (live) was not correlated with subsequent progeny production. During founding, queens lost a mean of 54% of their lean weight, 73% of their fat weight and 67% of their

Walter R. Tschinkel

1993-01-01

435

Diploid male production — a significant colony mortality factor in the fire ant Solenopsis invicta (Hymenoptera: Formicidae)  

Microsoft Academic Search

Two forms of the fire ant, Solenopsis invicta, occur in North America; the monogyne form has colonies with a single functional queen while the polygyne form has colonies containing many functional queens. Field surveys indicate that diploid males are common in natural populations of the polygyne form but absent from monogyne populations, in contrast to laboratory data showing that similar

Kenneth G. Ross; David J. C. Fletcher

1986-01-01

436

Mutual pheromonal inhibition among queens in polygyne colonies of the fire ant Solenopsis invicta  

Microsoft Academic Search

Summary Decrease in individual reproductive output with increasing numbers of reproductives is a general feature of social insect colonies. The previously described negative relationship between the fecundity of individual queens and number of resident queens in polygyne (multiple-queen) colonies of the fire ant Solenopsis invicta appears to result from mutual pheromonal inhibition. In an experimental test for the presence of

Edward L. Vargo

1992-01-01

437

A survey and comparison of luxury item ownership in the eighteenth century Dutch Cape Colony  

Microsoft Academic Search

What we know about the material culture of eighteenth century Cape Colony settlers is mostly limited to qualitative evidence found in official documents, letters, travel accounts and other correspondence. This paper uses a new quantitative source – the MOOC probate inventories – to ascertain the nature, growth and distribution of luxury good ownership in the Cape Colony. The survey reveals

Johan Fourie; Jolandi Uys

2011-01-01

438

Colony migration in the tropical honey bee Apis dorsata F. (Hymenoptera: Apidae)  

Microsoft Academic Search

Summary To obtain insights into the organization and adaptive significance of seasonal migration by colonies of the giant honey bee,Apis dorsata, we monitored the arrivals and departures of colonies in a rain forest habitat in northeastern Thailand, compared patterns of honey bee abundance with other measures of habitat variability, and observed the role of dance communication in organizing the migratory

F. C. Dyer; Th. D. Seeley

1994-01-01

439

Optimization design of three-phase asynchronous motor based on Multi-objective Ant Colony Algorithm  

Microsoft Academic Search

Based on the principle of ant colony algorithm, combined with the characteristics of three-phase asynchronous motor design, this paper applies a Multi-Objective Ant Colony Algorithm (MOACA) to three-phase asynchronous machine design, the detail process of optimization design is given. The optimization results of typical examples indicate that this method is effective.

Qingfeng Chen; Guoli Li; Qunjing Wang; Rui Zhou; Guanghui Fang; Wei Xu

2011-01-01

440

Optimization of multi-pass turning operations using ant colony system  

Microsoft Academic Search

This paper proposes a new optimization technique based on the ant colony algorithm for solving multi-pass turning optimization problems. The cutting process has roughing and finishing stages. The machining parameters are determined by minimizing the unit production cost, subject to various practical machining constraints. The results indicate that the proposed ant colony framework is effective compared to other techniques carried

K. Vijayakumar; G. Prabhaharan; P. Asokan; R. Saravanan

2003-01-01

441

Optimization design based on improved ant colony algorithm for PID parameters of BP neural network  

Microsoft Academic Search

Aiming at manually carry through optimization of experiment way adopted for traditional PID controller parameter, an optimization method based on improved ant colony algorithm for PID parameters of BP neural network is presented. The improved ant colony algorithm and BP neural is organically combined by this method. Which not only overcomes effectively the shortcoming of BP algorithm on some degree

Yan Zhao; Zhongjun Xiao; Jiayu Kang

2010-01-01

442

Application of a Human Tumor Colony-forming Assay to New Drug Screening1  

Microsoft Academic Search

The applicability of a human tumor colony-forming assay to drug screening was investigated in terms of feasibility, validity, and potential for discovering new antitumor drugs. Feasibility was addressed in a pilot study during which basic methods, appropriate assay quality controls, and a standardized protocol for screening were developed. Considerable variability was noted in the availability and colony growth of different

Robert H. Shoemaker; Mary K. Wolpert-DeFilippes; David H. Kern; Michael M. Lieber; Robert W. Makuch; Marmette R. Melnick; William T. Miller; Sydney E. Salmon; Richard M. Simon; John M. Venditti; Daniel D. Von Hoff

443

How Information-Mapping Patterns Determine Foraging Behaviour of a Honey Bee Colony  

Microsoft Academic Search

We have developed a model of foraging behaviour of a honeybee colony based on reaction-diffusion equations and have studied how mapping the information about the explored environment to the hive determines this behaviour. The model utilizes two dominant components of colony's foraging behaviour — the recruitment to the located nectar sources and the abandonment of them. The recruitment is based

Valery Tereshko; Troy Lee

2002-01-01

444

Effects of Nosema bombi and its treatment fumagillin on bumble bee ( Bombus occidentalis) colonies  

Microsoft Academic Search

We examined the effects of Nosema bombi (Microsporidia: Nosematidae) on colonies of bumble bees, Bombus occidentalis Greene (Hymenoptera: Apidae), used to pollinate tomatoes in commercial greenhouses. We assessed methods of detecting N. bombi and tested the effectiveness of fumagillin to control this parasite. N. bombi did not affect adult population size or amount of brood in B. occidentalis colonies. Fumagillin

Robin Whittington; Mark L. Winston

2003-01-01

445

Genotypic differences in brood rearing in honey bee colonies: context-specific?  

Microsoft Academic Search

Three experiments were performed to determine whether brood care in honey bee colonies is influenced by colony genetic structure and by social context. In experiment 1, there were significant genotypic biases in the relative likelihood of rearing queens or workers, based on observations of individually labeled workers of known age belonging to two visually distinguishable subfamilies. In experiment 2, no

Gene E. Robinson; Robert E. Page; Naomi Arensen

1994-01-01

446

The ontogeny of the interaction structure in bumble bee colonies: A MIRROR model  

Microsoft Academic Search

In this paper we present an individualoriented model of the behaviour of bumble bees on the comb. We show that the combination of the population dynamics of a bumble bee colony and simple behaviour of the adult bees on the comb is sufficient to generate the social interaction structure of the colony (and it ontogeny) as observed by van Honk

P. Hogeweg; B. Hesper

1983-01-01

447

Lubricating bacteria model for the growth of bacterial colonies exposed to ultraviolet radiation  

SciTech Connect

In this paper, we study the morphological transition of bacterial colonies exposed to ultraviolet radiation by modifying the bacteria model proposed by Delprato et al. Our model considers four factors: the lubricant fluid generated by bacterial colonies, a chemotaxis initiated by the ultraviolet radiation, the intensity of the ultraviolet radiation, and the bacteria's two-stage destruction rate with given radiation intensities. Using this modified model, we simulate the ringlike pattern formation of the bacterial colony exposed to uniform ultraviolet radiation. The following is shown. (1) Without the UV radiation the colony forms a disklike pattern and reaches a constant front velocity. (2) After the radiation is switched on, the bacterial population migrates to the edge of the colony and forms a ringlike pattern. As the intensity of the UV radiation is increased the ring forms faster and the outer velocity of the colony decreases. (3) For higher radiation intensities the total population decreases, while for lower intensities the total population increases initially at a small rate and then decreases. (4) After the UV radiation is switched off, the bacterial population grows both outward as well as into the inner region, and the colony's outer front velocity recovers to a constant value. All these results agree well with the experimental observations [Phys. Rev. Lett. 87, 158102 (2001)]. Along with the chemotaxis, we find that lubricant fluid and the two-stage destruction rate are critical to the dynamics of the growth of the bacterial colony when exposed to UV radiation, and these were not previously considered.

Zhang Shengli; Zhang Lei; Liang Run; Zhang Erhu; Liu Yachao; Zhao Shumin [Department of Applied Physics, Xi'an Jiaotong University, Xi'an 710049 (China)

2005-11-01

448

Lubricating bacteria model for the growth of bacterial colonies exposed to ultraviolet radiation  

Microsoft Academic Search

In this paper, we study the morphological transition of bacterial colonies exposed to ultraviolet radiation by modifying the bacteria model proposed by Delprato Our model considers four factors: the lubricant fluid generated by bacterial colonies, a chemotaxis initiated by the ultraviolet radiation, the intensity of the ultraviolet radiation, and the bacteria's two-stage destruction rate with given radiation intensities. Using this

Shengli Zhang; Lei Zhang; Run Liang; Erhu Zhang; Yachao Liu; Shumin Zhao

2005-01-01

449

Identification of Staphylococcus aureus Colony-Spreading Stimulatory Factors from Mammalian Serum  

PubMed Central

Staphylococcus aureus forms giant colonies on soft-agar surfaces, which is called colony-spreading. In the present study, we searched for host factors that influence S. aureus colony-spreading activity. The addition of calf serum, porcine serum, or silkworm hemolymph to soft-agar medium stimulated S. aureus colony-spreading activity. Gel filtration column chromatography of calf serum produced a high molecular weight fraction and a low molecular weight fraction, both of which exhibited colony-spreading stimulatory activity. In the low molecular weight fraction, we identified the stimulatory factor as bovine serum albumin. The stimulatory fraction in the high molecular weight fraction was identified as high-density lipoprotein (HDL) particles. Delipidation of HDL abolished the stimulatory activity of HDL. Phosphatidylcholine, which is the major lipid component in HDL particles, stimulated the colony-spreading activity. Other phosphatidylcholine-containing lipoprotein particles, low-density lipoprotein and very low-density lipoprotein, also showed colony-spreading stimulatory activity. These findings suggest that S. aureus colony-spreading activity is stimulated by albumin and lipoprotein particles in mammalian serum.

Omae, Yosuke; Sekimizu, Kazuhisa; Kaito, Chikara

2014-01-01

450

Colony Size of Phaeocystis Antarctica (Prymnesiophyceae) as Influenced by Zooplankton Grazers  

EPA Science Inventory

The haptophyte Phaeocystis antarctica is a dominant phytoplankton species in the Ross Sea, Antarctica, and exists as solitary cells and mucilaginous colonies that differ by several orders of magnitude in size. Recent studies with P. globosa suggested that colony formation and enl...

451

Identity and Sense of Belonging in Post-Colonial Education in Hong Kong  

ERIC Educational Resources Information Center

This paper explores the construction of local and national identities among secondary school students in post-colonial Hong Kong. As a Chinese society that has undergone a prolonged period of British colonial rule, the reunification of capitalist Hong Kong with the motherland under socialism in 1997 has set the context for a negotiation of…

Kuah-Pearce, Khun Eng; Fong, Yiu-Chak

2010-01-01

452

Sporulation patterning and invasive growth in wild and domesticated yeast colonies.  

PubMed

Different cell types can form patterns within fungal communities; for example, colonies of Saccharomyces cerevisiae form two sharply defined layers of sporulating cells separated by an intervening layer of unsporulated cells. Because colony sporulation patterns have only been investigated in a single laboratory strain background (W303), in this report we examined these patterns in other strain backgrounds. Two other laboratory strain backgrounds (SK1 and Sigma1278b) that differ from W303 with respect to colony morphology, invasive growth, and sporulation efficiency nevertheless displayed the same colony sporulation pattern as W303. This pattern was also observed in colonies of wild isolates of S. cerevisiae and Saccharomyces paradoxus. The wild yeast colonies sporulated on a much wider range of carbon sources than did the lab yeast and displayed a similar layered sporulation pattern when grown on either acetate or glucose medium and on either rich or synthetic medium. SK1, Sigma1278b and wild yeast colonies invaded the agar surface. The region of invasion varied between strains with respect to the organization and appearance of cells, but this invasion was always accompanied by sporulation. Thus, sporulation patterns are a general property of S. cerevisiae, and sporulation in colonies can be coordinated with invasive growth. PMID:20420901

Piccirillo, Sarah; Honigberg, Saul M

2010-06-01

453

Sporulation patterning and invasive growth in wild and domesticated yeast colonies  

PubMed Central

Different cell types can form patterns within fungal communities; for example, colonies of Saccharomyces cerevisiae form two sharply defined layers of sporulating cells separated by an intervening layer of unsporulated cells. Because colony sporulation patterns have only been investigated in a single laboratory strain background (W303), in this report we examined these patterns in other strain backgrounds. Two other laboratory strain backgrounds (SK1 and ?1278b) that differ from W303 with respect to colony morphology, invasive growth, and sporulation efficiency nevertheless displayed the same colony sporulation pattern as W303. This pattern was also observed in colonies of wild isolates of S. cerevisiae and S. paradoxus. The wild yeast colonies sporulated on a much wider range of carbon sources than did the lab yeast and displayed a similar layered sporulation pattern when grown on either acetate or glucose medium and on either rich or synthetic medium. SK1 and ?1278b and wild yeast colonies invaded the agar surface. The region of invasion varied between strains with respect to the organization and appearance of cells, but this invasion was always accompanied by sporulation. Thus, sporulation patterns are a general property of S. cerevisiae, and sporulation in colonies can be coordinated with invasive growth.

Piccirillo, Sarah; Honigberg, Saul M.

2010-01-01

454

Colony fusion and worker reproduction after queen loss in army ants  

PubMed Central

Theory predicts that altruism is only evolutionarily stable if it is preferentially directed towards relatives, so that any such behaviour towards seemingly unrelated individuals requires scrutiny. Queenless army ant colonies, which have anecdotally been reported to fuse with queenright foreign colonies, are such an enigmatic case. Here we combine experimental queen removal with population genetics and cuticular chemistry analyses to show that colonies of the African army ant Dorylus molestus frequently merge with neighbouring colonies after queen loss. Merging colonies often have no direct co-ancestry, but are on average probably distantly related because of overall population viscosity. The alternative of male production by orphaned workers appears to be so inefficient that residual inclusive fitness of orphaned workers might be maximized by indiscriminately merging with neighbouring colonies to increase their reproductive success. We show that worker chemical recognition profiles remain similar after queen loss, but rapidly change into a mixed colony Gestalt odour after fusion, consistent with indiscriminate acceptance of alien workers that are no longer aggressive. We hypothesize that colony fusion after queen loss might be more widespread, especially in spatially structured populations of social insects where worker reproduction is not profitable.

Kronauer, Daniel J. C.; Schoning, Caspar; d'Ettorre, Patrizia; Boomsma, Jacobus J.

2010-01-01

455

Silencing the Subaltern: Nation-State/Colonial Governmentality and Bilingual Education in the United States  

ERIC Educational Resources Information Center

This article introduces the concept of "nation-state/colonial governmentality" as a framework for analyzing the ways current language ideologies marginalize the language practices of subaltern populations. Specifically, the article focuses on the innate limitations of re-appropriating nation-state/colonial governmentality in an attempt…

Flores, Nelson

2013-01-01

456

Responses to human intruders by birds nesting in colonies: Experimental results and management guidelines  

USGS Publications Warehouse

Colonies of nesting wading birds and seabirds were studied at coastal sites in Virginia and North Carolina to determine distances at which birds flushed in response to human intrusion. There were few statistically significant relationships between flushing distances and colony size. Similarly, there were few differences between responses during incubation compared to post-hatching periods.

Erwin, R.M.

1989-01-01

457

Learning Abroad: The Colonial Educational Experiment in India, 1813-1919  

ERIC Educational Resources Information Center

This paper contributes to the special issue by offering a new framework in time periods that demonstrates the changing nature of the intellectual transfer to and from colonial India and to posit the imperatives that drove these changes. It shows that the nature of educational exchange in India was transformed in elemental ways during the colonial

Allender, Tim

2009-01-01

458

Biological constraints and colony founding in the polygynous invasive ant Lasius neglectus (Hymenoptera, Formicidae)  

Microsoft Academic Search

Summary. The polygynous invasive ant Lasius neglectus was described from Budapest, Hungary, as an unicolonial species, with no apparent colony barriers, and inferred intra-nidal mating without a nuptial flight. Here we analyze additional morphological characteristics of gynes, their physiological condition at emergence and at the time of mating and we describe the productivity of different types of colony founding in

X. Espadaler; S. Rey

2001-01-01

459

Genetic Studies on Small-colony Variants of Escherichia coli K-12  

Microsoft Academic Search

SUMMARY: Stable small-colony variants of Escherichia coli K-12 and several of its auxotrophs were isolated by treatment of cultures with copper sulphate solutions. These variants did not show any associated changes in nutritional, fermentative or serological characters. The small-colony forms showed normal recombining character in two instances, but in one variant the F - form showed a lower recombination rate

R. C. CLOWES; D. ROWLEY

1955-01-01

460

Colonial form, free-living corals, and macroborers from the Pleistocene of South Florida  

Microsoft Academic Search

Study of corallum shape in free-living colonies of Manicina, Siderastrea and Solenastraea collected from the Pleistocene Bermont formation in southern Florida indicates that they were mobile, either self-righting (Manicina), or rotatory (Siderastrea and Solenastraea), with colony forms that are the result of movement during growth. In rotatory corals, growth of a radial and centrifugal nature away from the corallum center

James E. Sorauf

2010-01-01

461

The Value of Post-Colonial Literature for Education Processes: Salman Rushdie's "Midnight's Children"  

ERIC Educational Resources Information Center

The author Salman Rushdie's post-colonial essay, "Midnight's Children," highlights a different perspective on the problems created by the colonial power where place and displacement are central themes and migration is a painful but emancipating process; both are expressed through the life of the writer, Salman Rushdie. The primary aim of this…

Schrottner, Barbara Theresia

2009-01-01

462

The organization of colony defense in the ant Pheidole dentata mayr (Hymenoptera: Formicidae)  

Microsoft Academic Search

1.Colonies of Pheidole dentata employ a complex strategy of colony defense against invading fire ants. Their responses can be conveniently divided into the following three phases: (1) at low stimulation, the minor workers recruit nestmates over considerable distances, after which the recruited major workers (“soldiers”) take over the main role of destroying the intruders; (2) when the fire ants invade

Edward O. Wilson

1976-01-01

463

The Preterm Prediction Study: Granulocyte colony-stimulating factor and spontaneous preterm birth  

Microsoft Academic Search

Objective:Granulocyte colony-stimulating factor is elevated in the amniotic fluid and plasma of women with chorioamnionitis and active preterm labor. We investigated the relationship between plasma granulocyte colony-stimulating factor and subsequent spontaneous preterm birth in pregnant women without symptoms.

Robert L. Goldenberg; William W. Andrews; Brian M. Mercer; Atef H. Moawad; Paul J. Meis; Jay D. Iams; Anita Das; Steve N. Caritis; James M. Roberts; Menachem Miodovnik; Kathryn Menard; Gary Thurnau; Mitchell P. Dombrowski; Donald McNellis

2000-01-01

464

A survey of honey bee colony losses in the United States, fall 2008 to spring 2009  

Microsoft Academic Search

Summary This study records the third consecutive year of high winter losses in managed honey bee colonies in the USA. Over the winter of 2008-9 an estimated 29% of all US colonies died. Operations which pollinated Californian almond orchards over the survey period had lower average losses than those which did not. Beekeepers consider normal losses to be 17.6%, and

Dennis vanEngelsdorp; Jerry Hayes; Robyn Underwood; Jeff Pettis

2010-01-01

465

Lack of Evidence for an Association between Iridovirus and Colony Collapse Disorder  

Microsoft Academic Search

Colony collapse disorder (CCD) is characterized by the unexplained losses of large numbers of adult worker bees (Apis mellifera) from apparently healthy colonies. Although infections, toxins, and other stressors have been associated with the onset of CCD, the pathogenesis of this disorder remains obscure. Recently, a proteomics study implicated a double-stranded DNA virus, invertebrate iridescent virus (Family Iridoviridae) along with

Rafal Tokarz; Cadhla Firth; Diana L. Cox-Foster; W. Ian Lipkin; Robin F. A. Moritz

2011-01-01

466

Synergistic Parasite-Pathogen Interactions Mediated by Host Immunity Can Drive the Collapse of Honeybee Colonies  

Microsoft Academic Search

The health of the honeybee and, indirectly, global crop production are threatened by several biotic and abiotic factors, which play a poorly defined role in the induction of widespread colony losses. Recent descriptive studies suggest that colony losses are often related to the interaction between pathogens and other stress factors, including parasites. Through an integrated analysis of the population and

Francesco Nazzi; Sam P. Brown; Desiderato Annoscia; Fabio Del Piccolo; Gennaro Di Prisco; Paola Varricchio; Giorgio Della Vedova; Federica Cattonaro; Emilio Caprio; Francesco Pennacchio

2012-01-01

467

Colony-based foraging segregation by Antarctic fur seals at the Kerguelen Archipelago  

Microsoft Academic Search

The foraging behaviour of conspecific female Antarctic fur seals (AFS) was compared simultaneously at 2 breeding colonies at Îles Kerguelen (S Indian Ocean). A remnant colony at ÎIes Nuageuses (IN) thought to have escaped sealing is hypothesized to be the source of increasing fur seal numbers at Cap Noir (CN) on the Kerguelen mainland. Inter-annual variability in foraging areas is

Mary-Anne Lea; Christophe Guinet; Yves Cherel; Mark Hindell; Laurent Dubroca; Sam Thalmann

2008-01-01

468

Substrate preferences of a non-colonial kamptozoan, and its interactions with bryozoan hosts  

Microsoft Academic Search

Results of substrate preference analysis for Loxosomella nordgaardi Ryland (Kamptozoa: Loxosomatidae) found in association with various bryozoan species in the White Sea are presented. Local water-current patterns, for the first time observed and documented in bryozoan colonies inhabited by non-colonial entoprocts, indicate the direct dependence of kamptozoans' feeding activity on the bryozoan host. It is shown that because of the

E. L. Yakovis

2002-01-01

469

Mapping some landscapes of colonial-global childhood ece@2000.europe.antipodes  

Microsoft Academic Search

This article sketches some historical maps of the child institutions in Aotearoa — New Zealand. These reveal a dynamic process of accommodation and resistance by early childhood constituencies to shifting political and pedagogical agendas. The landscape for these maps are, however, multi-layered set against a backdrop of colonial values which portray:some portraits of colonial childhood; but differently constructed for the

Helen May

2001-01-01

470

Constructing Indigenous ChildhoodsColonialism, Vocational Education and the Working Child  

Microsoft Academic Search

Through interrogating our prevailing understanding of childhoods of the poor in the Third World as `traditional', this article attempts to make apparent the significant break that colonialism signified in these lives. It does so through locating a Calcutta street child's vocational education experiences within a historical understanding of the workings of colonial education policies. The effort in the article is

SARADA BALAGOPALAN

2002-01-01

471

Benjamin Franklin's Pictorial Representations of the British Colonies in America: A Study in Rhetorical Iconology.  

ERIC Educational Resources Information Center

Investigates the underlying reasons for the fundamental shift in Benjamin Franklin's portrayals of the British colonies in America. Explores the hypothesis that "Magna Britannia" was both a deliberative work directed toward the British Parliament and an apologetic work directed toward conservatives in the colonial public. Also discusses Franklin's…

Olson, Lester C.

1987-01-01

472