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Wastewater from infected leprosy patients is expected to contain considerably higher concentrations of pathogens than standard domestic wastewater and, therefore, is more infectious. Isolation of lepers' is thought to prevent the spread of a wide range of infectious diseases that could potentially be contacted through direct or indirect exposure from an infected person's wastewater in the surrounding environment. However, inappropriate
Akinwale O. Coker; Johnson R. Oluremi; Rebecca A. Adeshiyan; Mynepalli K. Sridhar; Morenike E. Coker; Colin A. Booth; Jennifer A. Millington; Jamal M. Khatib
Quantities and types of solid wastes generated at Ogbomosho leprosarium (Oyo State, Nigeria) have been investigated. Data collection, through waste sampling and analysis, interviews, questionnaire surveys and field observations, was conducted between August and November 2006. Results indicate a notably low mean waste generation rate of 241.5 g\\/h\\/d, which included bandages, paper, food waste, animal waste, wood ash, yard trimmings,
A. O. Coker; R. A. Adeshiyan; J. R. Oluremi; M. K. Sridhar; M. E. Coker; C. A. Booth; J. M. Khatib
This paper provides insight into interdependent processes by which leprosy and foreignness were constructed in early modern Germany. The results are based on a case study and further source-samples from Imperial towns of the Swabian and Franconian district. As it seems the early modern period was characterized by an ambivalent attitude towards lepers resulting in a variety of ways of inclusion and of exclusion for these persons: The separation from certain forms of social life in the towns (and in the villages belonging to the respective territory) followed the "suspicion" by other inhabitants caused by physical "signs" and the confirmed diagnoses of leprosy by medical experts. Such alienation from one community was juxtaposed by a right to enter the towns in rather specific circumstances as group of alms-beggars or part of a festive community and to join the community of leprosaria. The admission to such houses on the other hand was associated with the status of a burgher, a status, however, which could not be gained by everybody and was not fixed for life but was flexible. We found evidence that the status of leprosarium-"burgher" could be negotiated, interchanged, abandoned by lepers or be granted, refused, denied, suspended by the authorities--temporarily and permanently. By such means affiliation and foreignness were constructed. Preliminary analysis of numbers at ceremonies suggest that a large number of lepers was mobile--whether voluntarily or forced has still to be found out. And they represented the double fold estranged who, albeit, were temporarily included into the celebrating or commemorating community. Such forms of inclusion of the excluded, on the other hand, caused suspicion of simulation which became increasingly the preoccupation of the authorities. PMID:21863698
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
The CEO of Carter Myers Automotive must consider his promotional plan for the coming summer. His company owned and operated three Virginia automotive dealerships: Colonial Auto Center in Charlottesville, Colonial Honda in Petersburg, and Heritage Chevrolet-Geo in Chester. Colonial was a multifranchise dealership featuring vehicles manugactured by Lincoln, Mercury, Cadillac, Buick, Pontiac, Nissan, Mitsubishi, suzuki cars, and GMC trucks. Several
In heavily irradiated mice, bone marrow regeneration of either endogenous or exogenous origin was shown to occur in discrete foci comparable to the more intensively studied spleen colonies. The number of endogenous bone marrow colonies was inversely related to dose of whole body X-irradiation. Endogenous marrow colonies were found after higher doses of irradiation than were endogenous spleen colonies. Most of them were granulocytic in nature. Exogenous bone marrow colonies in lethally irradiated mice injected with bone marrow cells were proportional in number to the dose of cells injected, appeared at a time comparable to spleen colonies like which, at 7 or 8 days, they were of single differentiated cell line, either granuloid or erythroid or megakaryocytic, with a small percentage of "mixed" colonies. Whereas erythroid colonies outnumber granuloid colonies in spleen, either in situ or subcutaneously transplanted (E:G colony ratio of about 3.5), granuloid colonies outnumber erythroid in bone marrow (E:G colony ratio of about 0.7). The characteristic E:G colony ratios of spleen and marrow appear more likely to be the result of a hemopoietic organ stromal influence on pluripotent colony forming units (CFU's) than of selective lodgment of committed (unipotent) granuloid and erythroid CFU's in bone marrow and spleen, respectively, as indicated by the following. Bone marrow stem cells (CFU) which had reseeded the marrow cavity of irradiated primary recipients 18–24 hr earlier, were reharvested and retransplanted intravenously into irradiated secondary hosts. The E:G colony ratio of the colonies formed in the spleen of the secondary hosts was typical of primary spleen colonies (2.8), that of the colonies formed in the marrow cavity was typical of bone marrow colonies (0.6). Pieces of marrow stroma containing reseeded CPU's from the contralateral femur of these same primary recipients were implanted by trocar directly into the spleens of other irradiated secondary recipients. Those CPU's that developed in the intrasplenic-implanted marrow stroma yielded an. E:G colony ratio of 0.1. Those that migrated into the contiguous and remote portions of the spleen gave E:G colony ratios of 2.9 and 2.4, respectively. Irradiated marrow stroma and normal spleen CPU's (a 1 mm cube of spleen) were loaded into the same trocar and implanted directly into the spleens of irradiated mice. The spleen CFU's that migrated into the implanted marrow stroma yielded five granuloid and two mixed colonies. The larger number that developed in the host spleen yielded an E:G colony ratio of 2.9 or higher. Of those 19 mixed colonies that bridged the junction of spleen and implanted marrow stroma in each of the above two experiments, in every case, the erythroid portion of the colony was in the splenic stroma, the granuloid portion was in the marrow stroma.
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.
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
Originally, learning automata (LAs) were introduced to describe human behavior from both a biological and psychological point of view. In this paper, we show that a set of interconnected LAs is also able to describe the behavior of an ant colony, capable of finding the shortest path from their nest to food sources and back. The field of ant colony
Explore the town of Boston and its natural and human-made features in colonial times in this interactive activity produced by WGBH and featuring materials from the Norman B. Leventhal Map Center at the Boston Public Library.
The emergent spatial patterns generated by growing bacterial colonies have been the focus of intense study in physics during\\u000a the last twenty years. Both experimental and theoretical investigations have made possible a clear qualitative picture of\\u000a the different structures that such colonies can exhibit, depending on the medium on which they are growing. However, there\\u000a are relatively few quantitative descriptions
Juan A. Bonachela; Carey D. Nadell; Joăo B. Xavier; Simon A. Levin
The Ant Colony Optimization project uses the behavior of ants as a model to solve optimization problems, such as how to minimize Internet traffic congestion. Several downloadable research papers are included on the project's homepage, as well as links to news stories, radio broadcasts, and conference proceedings about ant algorithms.
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.
A central element of the narrative circulated by the Tibet Movement has been that China has carried out genocide and practised colonialism in Tibet. These notions are, for the most part, uncritically accepted by politicians and the media, especially in the West. This essay challenges such characterizations as inept and as obstacles to resolving the Tibet Question. It looks at
As the American nation developed through periods of rapid change and great cultural diversity, the American public school system served as a primary souce of national unity. The roots of comprehensive public education in America can be traced to the educational system developed by 17th century Puritan colonials. Although one of the central…
The emergent spatial patterns generated by growing bacterial colonies have been the focus of intense study in physics during the last twenty years. Both experimental and theoretical investigations have made possible a clear qualitative picture of the different structures that such colonies can exhibit, depending on the medium on which they are growing. However, there are relatively few quantitative descriptions of these patterns. In this paper, we use a mechanistically detailed simulation framework to measure the scaling exponents associated with the advancing fronts of bacterial colonies on hard agar substrata, aiming to discern the universality class to which the system belongs. We show that the universal behavior exhibited by the colonies can be much richer than previously reported, and we propose the possibility of up to four different sub-phases within the medium-to-high nutrient concentration regime. We hypothesize that the quenched disorder that characterizes one of these sub-phases is an emergent property of the growth and division of bacteria competing for limited space and nutrients.
Bonachela, Juan A.; Nadell, Carey D.; Xavier, Joăo B.; Levin, Simon A.
An examination of colonies of 51 strains of Actinobacillus mallei grown on a complex agar medium containing heart infusion broth, yeast extract, glucose, and glycerol indicated a high degree of heterogeneity in respect of colonial morphology both within a...
This report examines the recent sharp decline in U.S. honey bee colonies, which scientists are now calling the Colony Collapse Disorder (CCD). This phenomenon first became apparent among commercial migratory beekeepers along the East Coast during the last...
Starting in late 2006, commercial migratory beekeepers along the East Coast of the United States began reporting sharp declines in their honey bee colonies. Because of the severity and unusual circumstances of these colony declines, scientists named this ...
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.
Leprosy elimination (<1/100 000) is almost reached all around the world, although, but disabled people are still a lot, and they need rehabilitation as soon as possible. The different lesions (neurological, dermatologic and joint) must be treated in order to protect from handicap. Physical rehabilitation medicine can help with a global and polyvalent coverage. Therapeutic education and reinsertion are an important part. PMID:22393618
De Brier, G; Jouvion, A; Mercier, J; Trappier, T; Urseau, I; Thefenne, L
OBJECTIVE Hepatitis C virus is the most prevalent chronic blood-borne infection in the United States, typically acquired through contaminated blood products or needle sharing. We hypothesized that patients with chronic hepatitis C infection experience stigmatization independent of mode of acquisition and that it negatively affects quality of life. DESIGN Cross-sectional observation study. SETTING Specialty clinic in a tertiary referral hospital. PATIENTS Two hundred and ninety outpatients diagnosed with chronic hepatitis C infection and seen in a hepatology clinic. Thirty participants were excluded because of missing data. MEASUREMENTS AND MAIN RESULTS Patients were asked to complete a demographic profile, a semistructured interview, the Sickness Impact Profile, and the Hospital Anxiety Depression Scale. A team of two blinded coders analyzed the interviews. A total of 147 of the 257 study patients experienced stigmatization that they attributed to the disease. Women were more likely to report perceived stigmatization than men (P < .05). Age, education, professional status, and mode of infection did not influence the likelihood of stigmatization. Stigmatization was associated with higher anxiety (P < .01) and depression (P < .01), worsened quality of life (P < .01), loss of control (P < .01), and difficulty coping (P < .01). Individuals who experienced stigmatization also mentioned problems in their health care (P < .01) and work environment (P < .01) as well as with family members (P < .01). CONCLUSION Stigmatization is a very common emotionally burdensome experience for patients with hepatitis C, which can erode social support. As it penetrates even into the health care environment, physicians and other care providers should be aware of the existence and impact of such negative stereotyping.
Zickmund, Susan; Ho, Evelyn Y; Masuda, Masahiro; Ippolito, Laura; LaBrecque, Douglas R
Honeybees, Apis spp., maintain elevated temperatures inside their nests to accelerate brood development and to facilitate defense against predators. We present an additional defensive function of elevating nest temperature: honeybees generate a brood-comb fever in response to colonial infection by the heat-sensitive pathogen Ascosphaera apis. This response occurs before larvae are killed, suggesting that either honeybee workers detect the infection before symptoms are visible, or that larvae communicate the ingestion of the pathogen. This response is a striking example of convergent evolution between this "superorganism" and other fever-producing animals.
Starks, P. T.; Blackie, Caroline A.; Seeley, Thomas D.
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 ...
For many years, the oil shale boom in W. Colorado has been just around the corner. The Colony Shale Oil Project is a joint development of the Oil Shale Corp. and Exxon Corp. The Colony operation is located in Garfield County in NW Colorado. To support the plant, it will be necessary to produce 66,000 tons/day of oil shale from a conventional room-and-pillar mine. The shale will be hauled from the mine and crushed to -9 in. (229mm). The coarse ore then will be transported to the secondary crushing station where it will be further reduced to -1/2 in. (13 mm). The finely crushed shale will enter 6 Tosco II retorts, each capable of processing 11,000 tons/day. When heated to 900 F (482 C) in the pyrolysis drum, the kerogen vaporizes and is separated from the spent shale. The oil shale vapors then are condensed, fractionated, and upgraded by hydrotreating before entering a pipeline to be transported to a conventional refinery.
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.
The College of William & Mary is one of the oldest institutions of higher learning in the United States, and they have a rich history interwoven with the history of the U.S. and the state of Virginia. Recently, they have begun adding a wide range of institutional documents to their digital archive. This section of the site features The Colonial Echo, which has served as the student yearbook of the College since 1899. The yearbook includes information about student groups and activities, campus events, scenes of campus, and materials on university administrators. The digitization project was made possible via funds from Professor Emeriti Richard Sherman and Armand Galfo. These unique documents capture moments of college frivolity, seriousness of purpose, and gravitas.
Today we are going to research about the 13 colonies. Here are the things you will be learning about: What were the first 13 colonies? What year was each colony discovered? Who discovered each colony? Compare and contrast life in colonial days with life in ancient Hawaii.
The basis for the severe discipline imposed on school children in colonial America, especially in the Puritan colonies, was the belief in original sin. The child was regarded as being born in sin and thus depraved and prone to sin. The purpose of education was to enable children to read the Bible and thus change the behavior which otherwise would…
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
Ammonia emissions were measured from two entire seabird colonies with contrasting species assemblages, to ascertain the ammonia volatilisation potentials among seabird species in relation to their nesting behaviour. Emissions were calculated from downwind plume measurements of ammonia concentration using both inverse dispersion and tracer ratio methods. Measured colony emissions ranged 1-90 kg NH3 hour-1, and equated to 16 and 36% volatilization of excreted nitrogen for colonies dominated by ground/burrow nesting and bare rock nesting birds, respectively. The results were applied in a bioenergetics model with a global seabird database. Seabird colonies are found to represent the largest point sources of ammonia globally (up to ~6 Gg NH3 colony-1 year-1). Moreover the largest emissions occur mainly in remote environments with otherwise low NH3 emissions. These ammonia ``hot spots'' explain significant perturbations of the nitrogen cycle in these regions and add ~20% to oceanic ammonia emissions south of latitude 45°S.
Blackall, Trevor D.; Wilson, Linda J.; Theobald, Mark R.; Milford, Celia; Nemitz, Eiko; Bull, Jennifer; Bacon, Philip J.; Hamer, Keith C.; Wanless, Sarah; Sutton, Mark A.
The essay explores the hypothesis of colonial collecting processes involving the active addition of the colonial context and historical past to museum objects through the production of short stories. It examines the emergent historicity of collections through a focus on the "histories" that museum workers and colonial agents have been attaching to scientific collections of human skulls. Drawing on the notions of collection trajectory and historiographical work, it offers an alternative perspective from which to approach the creation of singular histories and individual archives for objects in collections. PMID:22371979
Multiple Objective Optimisation is a fast growing area of research, and consequently several Ant Colony Optimisation approaches\\u000a have been proposed for a variety of these problems. In this paper, a taxonomy for Multiple Objective Ant Colony Optimisation\\u000a algorithms is proposed and many existing approaches are reviewed and described using the taxonomy. The taxonomy offers guidelines\\u000a for the development and use
Presented by Dinsmore Documentation, Classics of American Colonial History is a research database consisting of scholarly books and articles on American colonial history that, according to the creators, "appear to be of continuing interest." The collection currently offers 22 source materials by 15 different authors. Browseable by author or subject, the collection contains subject categories including Administration, African Americans and Slavery, Economics and Trade, Immigration from Europe, Law, Native Americans, Politics, Religion, and Wars.
The computational model from life system has become a main intelligent algorithm. Ant colony algorithm is a new computational model from mimic the swarm intelligence of ant colony behavior. And it is a very good combination optimization method. To extend the ant colony algorithm, some continuous ant colony algorithms have been proposed. To improve the searching performance, the principles of
SUMMARY In addition to R outgrowths, strains of Lactobacillus casei growing on a carbohydrate-free medium also formed smooth secondary colonies situated on the primary colonies. These secondary colonies arose after about 6 days of incubation and were of two types : when centrally situated they formed papillae; when near the margin of the mother colony they often spilt over and
Intensive surveys of an area of woodland in Phitsanulok province, Thailand, revealed 15 colonies of Apis florea. The colonies had a highly aggregated spatial distribution (Standardized Morisita’s Index of Dispersion = 0.59). Microsatellite\\u000a analysis based on 5 loci showed that no colonies were related as mother-daughter, suggesting that unrelated colonies tend\\u000a to nest near existing colonies.
Wandee Wattanachaiyingcharoen; Siriwat Wongsiri; Benjamin P. Oldroyd
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…
Workers of polydomous colonies of social insects must recognize not only colony-mates residing in the same nest but also those living in other nests. We investigated the impact of a decentralized colony structure on colony- and nestmate recognition in the polydomous Australian meat ant (Iridomyrmex purpureus). Field experiments showed that ants of colonies with many nests were less aggressive toward
E. van Wilgenburg; D. Ryan; P. Morrison; P. J. Marriott; M. A. Elgar
The formation of concentric ring colonies by bacterial species Bacillus subtilis and Proteus mirabilis has been investigated experimentally, focusing our attention on the dependence of local cell density upon the bacterial motility. It has been confirmed that these concentric ring colonies reflect the periodic change of the bacterial motility between motile cell state and immotile cell state. We conclude that this periodic change is macroscopically determined neither by biological factors (i.e., biological clock) nor by chemical factors (chemotaxis as inhibitor). And our experimental results strongly suggest that the essential factor for the change of the bacterial motility during concentric ring formation is the local cell density.
SUMMARY Recently, researchers in various fields have shown interest in the behavior of creatures from the viewpoint of adaptiveness and flexibility. Ants, known as social insects, exhibit collective behavior in performingtasks that can not be carried out by an individual ant. In ant colonies, chemical sub- stances, called pheromones, are used as a way to communicate important information on global
Honey bee queens mate with many males, creating numerous patrilines within colonies that are genetically distinct. The effects of genetic diversity on colony productivity and long-term fitness are unknown. We show that swarms from genetically diverse colonies (15 patrilines per colony) founded new colonies faster than swarms from genetically uniform colonies (1 patriline per colony). Accumulated differences in foraging rates,
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 FreedmenÂs 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.
Ants, as paradigm of social insects, have become a recurrent example of efficient problem solvers via self-organization. In spite of the simple behavior of each individual, the colony as a whole displays “swarm intelligence:” the organization of ant trails for foraging is a typical output of it. But conventional techniques of observation can hardly record the amount of data needed
C. Noda; J. Ferna´ndez; C. Pe´rez-Penichet; E. Altshuler
The very basis of this thesis is the collective behavior of ants in colonies. Ants are an excellent example of how rather simple behavior on a local level can lead to complex behavior on a global level that is beneficial for the individuals. The key in the self-organization of ants is communication through pheromones. When an ant forages for food,
This section will deal with the culture technique, growth characteristics, and properties of the M-CFC(Macrophage Colony Forming Cell) a CFC distinct in many ways from the more primitive GM(Granulocyte Macrophage)-CFC and HPP(Hematopoietic Progenitor Cell...
The report is a summary of data collected from 1972 to 1982 on the location, size, and species composition of seabird colonies in Washington. It documents more than 440 nesting areas, with a total of more than 300,000 birds, within the marine shoreline ha...
Multi colony ant algorithms are evolutionary optimization heuristics that are well suited for parallel execution. Information exchange between the colonies is an important topic that not only influences the parallel execution time but also the optimization behaviour. In this paper different kinds of information exchange strategies in multi colony ant algorithms are investigated. It is shown that the exchange of
Martin Middendorf; Frank Reischle; Hartmut Schmeck
We describe an artificial ant colony capable of solving the traveling salesman problem (TSP).Ants of the artificial colony are able to generate successively shorter feasible tours by usinginformation accumulated in the form of a pheromone trail deposited on the edges of the TSPgraph. Computer simulations demonstrate that the artificial ant colony is capable of generatinggood solutions to both symmetric and
|Dialogue and illustrations trace the history of the first peoples of South, Central, and North America and encourage students to look at past and present patterns of colonialism and to view colonialism from the perspective of the colonized. Chapter 1 critiques Columbus 500 years after founding the first colony in the Americas. Chapter 2 presents…
Bacterial colony enumeration is an essential tool for many widely used biomedical assays. However, bacterial colony enumerating is a low throughput, time consuming and labor intensive process since there might exist hundreds or thousands of colonies on a Petri dish, and the counting process is often manually performed by well-trained technicians. In this paper, we introduce a fully automatic yet
Long-term growth in developing countries has been explained in four frameworks: ‘extractive colonial institutions’ (Acemoglu et al., 2001), ‘colonial legal origin’ (La Porta et al., 2004), ‘geography’ (Gallup et al., 1998) and ‘colonial human capital’ (Glaeser et al., 2004). In this paper we test the ‘colonial human capital’ explanation for sub-Saharan Africa, controlling for legal origin and geography. Utilising data
Workers of polydomous colonies of social insects must recognize not only colony-mates residing in the same nest but also those living in other nests. We investigated the impact of a decentralized colony structure on colony- and nestmate recognition in the polydomous Australian meat ant (Iridomyrmex purpureus). Field experiments showed that ants of colonies with many nests were less aggressive toward alien conspecifics than those of colonies with few nests. In addition, while meat ants were almost never aggressive toward nestmates, they were frequently aggressive when confronted with an individual from a different nest within the same colony. Our chemical analysis of the cuticular hydrocarbons of workers using a novel comprehensive two-dimensional gas chromatography technique that increases the number of quantifiable compounds revealed both colony- and nest-specific patterns. Combined, these data indicate an incomplete transfer of colony odor between the nests of polydomous meat ant colonies. PMID:16555093
van Wilgenburg, E; Ryan, D; Morrison, P; Marriott, P J; Elgar, M A
Workers of polydomous colonies of social insects must recognize not only colony-mates residing in the same nest but also those living in other nests. We investigated the impact of a decentralized colony structure on colony- and nestmate recognition in the polydomous Australian meat ant ( Iridomyrmex purpureus). Field experiments showed that ants of colonies with many nests were less aggressive toward alien conspecifics than those of colonies with few nests. In addition, while meat ants were almost never aggressive toward nestmates, they were frequently aggressive when confronted with an individual from a different nest within the same colony. Our chemical analysis of the cuticular hydrocarbons of workers using a novel comprehensive two-dimensional gas chromatography technique that increases the number of quantifiable compounds revealed both colony- and nest-specific patterns. Combined, these data indicate an incomplete transfer of colony odor between the nests of polydomous meat ant colonies.
van Wilgenburg, E.; Ryan, D.; Morrison, P.; Marriott, P. J.; Elgar, M. A.
\\u000a This chapter discusses in detail individual honeybees fending off an enemy and the effects that can be rendered when whole\\u000a colony defence is a coordinated, social effort. Enemies extend from viruses to bears. Whatever the predator, the nesting styles\\u000a and nests of the bees afford a first line of defence. These are supplemented by various weapons, including stings, mandibles,\\u000a legs
\\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
Ant colony optimization (ACO) can be applied to the data mining field to extract rule-based classifiers. The aim of this paper is twofold. On the one hand, we provide an overview of previous ant-based approaches to the classification task and compare them with state-of-the-art classification techniques, such as C4.5, RIPPER, and support vector machines in a benchmark study. On the
David Martens; Manu De Backer; Raf Haesen; Jan Vanthienen; Monique Snoeck; Bart Baesens
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
A highly polymorphic Xenorhabdus luminescens strain was isolated. The primary form of X. luminescens was luminescent and nonswarming and produced a yellow pigment and antimicrobial substances. The primary form generated a secondary form that had a distinct orange pigmentation, was weakly luminescent, and did not produce antimicrobial substances. Both the primary and secondary forms generated a set of colony variants at frequencies that exceeded normal rates for spontaneous mutation. The variant forms include nonswarming and swarming forms that formed large colonies and a small-colony (SC) form. The primary and secondary forms generated their SC forms at frequencies of between 1 and 14% and 1 and 2%, respectively. The SC forms were distinct from their parental primary and secondary forms in colony and cellular morphology and in protein composition. The cellular morphology and protein patterns of the nonswarming and swarming colony variants were all very similar. The DNA fingerprints of all forms were similar. Each SC-form colony reverted at high frequency to the form from which it was derived. The proportion of parental-type cells in the SC-form colonies varied with age, with young colonies containing as few as 0.0002% parental-type cells. The primary-to-secondary switch was stable, but all the other colony forms were able to switch at high frequencies to the alternative colony phenotypes. Images
Hurlbert, Ronald E.; Xu, Jimin; Small, Christopher L.
In socially foraging species resource information can be shared between individuals, increasing foraging success. In ant colonies, nestmate recruitment allows high exploitation rates at known resources however, to maximise foraging efficiency this must be balanced with searching for new resources. Many ant species form colonies inhabiting two or more spatially separated but socially connected nests: this type of organisation is known as polydomy. Polydomous colonies may benefit from increased foraging efficiency by carrying out dispersed-central place foraging. However, decentralisation of the colony may affect recruitment success by limiting interaction between ants based in separate nests. We use an agent-based model which compares the foraging success of monodomous and polydomous colonies in different food environments, incorporating recruitment through pheromone trails and group foraging. In contrast to previous results we show that polydomy is beneficial in some but not all cases. Polydomous colonies discover resources at a higher rate, making them more successful when food is highly dispersed, but their relative success can be lowered by limitations on recruitment success. Monodomous colonies can have higher foraging efficiency than polydomous colonies by exploiting food more rapidly. The results show the importance of interactions between recruitment strategy, colony size, and colony organisation. PMID:23380232
\\u000a This paper presents a Multiple Ant Colony Optimization (MACO) approach for load balancing in circuit-switched networks. Based on the problem-solving approach of ants in nature, Ant Colony\\u000a Optimization (ACO) has been applied to solve problems in optimization, network routing and load balancing by modeling ants\\u000a as a society of mobile agents. While traditional ACO approaches employed one ant colony for
Ants use a great variety of recruitment methods to forage for food or find new nests, including tandem running, group recruitment and scent trails. It has been known for some time that there is a loose correlation across many taxa between species-specific mature colony size and recruitment method. Very small colonies tend to use solitary foraging; small to medium sized colonies use tandem running or group recruitment whereas larger colonies use pheromone recruitment trails. Until now, explanations for this correlation have focused on the ants' ecology, such as food resource distribution. However, many species have colonies with a single queen and workforces that grow over several orders of magnitude, and little is known about how a colony's organization, including recruitment methods, may change during its growth. After all, recruitment involves interactions between ants, and hence the size of the colony itself may influence which recruitment method is used--even if the ants' behavioural repertoire remains unchanged. Here we show using mathematical models that the observed correlation can also be explained by recognizing that failure rates in recruitment depend differently on colony size in various recruitment strategies. Our models focus on the build up of recruiter numbers inside colonies and are not based on optimality arguments, such as maximizing food yield. We predict that ant colonies of a certain size should use only one recruitment method (and always the same one) rather than a mix of two or more. These results highlight the importance of the organization of recruitment and how it is affected by colony size. Hence these results should also expand our understanding of ant ecology. PMID:20694195
Planqué, Robert; van den Berg, Jan Bouwe; Franks, Nigel R
Honey bee queens mate with many males, creating numerous patrilines within colonies that are genetically distinct. The effects of genetic diversity on colony productivity and long-term fitness are unknown. We show that swarms from genetically diverse colonies (15 patrilines per colony) founded new colonies faster than swarms from genetically uniform colonies (1 patriline per colony). Accumulated differences in foraging rates, food storage, and population growth led to impressive boosts in the fitness (i.e., drone production and winter survival) of genetically diverse colonies. These results further our understanding of the origins of polyandry in honey bees and its benefits for colony performance. PMID:17641199
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
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 trea...
In this paper, the ant colony search algorithm (ACSA) is proposed to solve the thermal unit commitment problem. ACSA is a new cooperative agents approach, which is inspired by the observation of the behaviors of real ant colonies on the topic of ant trial formation and foraging methods. In the ACSA, a set of cooperating agents called \\
In this paper, ant colony search algorithm (ACSA) is proposed to solve the economic dispatch (ED) with transmission losses problem. ACSA is a new cooperative agents approach, which is inspired by the observation of the behaviors of real ant colonies on the topic of ant trail formation and foraging methods. In the ACSA, a set of cooperating agents called \\
New scholarship on economic development in Korea has focused on the beneficial effects of Japanese colonialism and on certain continuities between Korea's growth strategy before and after World War II. We challenge this new revisionism. The growth record under the Japanese occupation was more modest than is often thought, there are greater discontinuities than continuities between the colonial and postwar
Between 1946 and 1976, the European powers granted independence to all of their large colonies in Africa and Southeast Asia. This paper attempts to provide an economic explanation for this remarkable ending to the era of colonialism. The main theoretical innovation is to consider the effect of population increase on the allocation of time by the indigenous population between productive
|This illustrated unit of study can be incorporated into regular social studies courses in elementary classrooms. The unit focuses on life in the 13 original colonies from the settlement period to the Revolutionary War. Activities are provided to help students learn the names and locations of the colonies. A highlight of the unit is a study of the…
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
THEMAJOR CONTRIBUTION of two hundred years of British colonial rule to Indian publishing is an internal market for books in the English language -a market that persists and even grows despite the end of direct colonial domination in 1947. This has had a profound effect, for good and ill, on the growth of Indian publishing since independence. On the positive
Hemadsorption by colonies of Ureaplasma urealyticum and Mycoplasma pneumoniae differed quantitatively and qualitatively. Using standard methodology, few strains of U. urealyticum hemadsorbed; with a modified method, most strains hemadsorbed, indicating a second type of association. Scanning electron microscopy of tannin-osmium-stained preparations showed guinea pig erythrocytes embedded in ureaplasma colonies and craters left when erythrocytes were dislodged. PMID:2037381
We examine the Genetically Modified Ant Colony System (GMACS) algorithm (3), which claims to dynamically tune an Ant Colony Optimization (ACO) algorithm to its near-optimal parameters. While our research indicates that the use of GMACS does result in higher quality solutions over a hand-tuned ACO algorithm, we found that the algorithm is ultimately hindered by its emphasis on randomized ant
|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.…
Managed honey bee colonies are currently affected by abrupt depopulation during winter and many factors are suspected to be involved, either alone or in combination. Pathogens are considered as principal actors, contributing to weaken colony health and leaving room for secondary infections. In parti...
|Energy development has led many people concerned with the American West to consider it a powerless colony of outside interests. The characteristics of colonies, particularly external control by energy companies and the federal government, and the applicability of these characteristics to the West are discussed. (IS)|
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…
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
Most existing historiographies of colonial and post-colonial policing in Ghana have focused nearly exclusively on providing a basic understanding of managerial issues—that is, organisational and administrative structure, functions and modes of operation. Our knowledge of issues of police legitimation, and of the ‘quality of policing’ remains very limited. This article discusses these issues and establishes the vital importance of history
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 ...
This illustrated unit of study can be incorporated into regular social studies courses in elementary classrooms. The unit focuses on life in the 13 original colonies from the settlement period to the Revolutionary War. Activities are provided to help students learn the names and locations of the colonies. A highlight of the unit is a study of the…
|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…
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
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
Laboratory-reared western corn rootworms, Diabrotica virgifera virgifera, from colonies maintained at the North Central Agricultural Research Laboratory (NCARL) in Brookings, SD, are used extensively by many researchers in studies of the biology, ecology, behavior, and genetics of this major insect pest. A nondiapause colony developed through artificial selection in the early 1970s is particularly attractive for many studies because its generation time is much shorter than that of typical diapause colonies. However, the nondiapause colony has been in culture for approximately 190 generations without out-crossing. We compared variation at six microsatellite loci among individuals from the NCARL nondiapause colony (approximately 190 generations), main diapause colony (approximately 22 generations), four regional diapause colonies (3-8 generations), and four wild populations. Genetic diversity was very similar among the diapause laboratory colonies and wild populations. However, the nondiapause colony showed approximately 15-39% loss of diversity depending on the measure. Pairwise estimates of F(ST) were very low, revealing little genetic differentiation among laboratory colonies and natural populations. The nondiapause colony showed the greatest genetic differentiation with an average pairwise F(ST) of 0.153. There was little evidence that the laboratory colonies had undergone genetic bottlenecks except for the nondiapause colony. The nondiapause colony has suffered a moderate loss in genetic diversity and is somewhat differentiated from wild populations. This was not unexpected given its history of artificial selection for the nondiapause trait, and the large number of generations in culture. In contrast, the results indicate that the diapause colonies maintained at NCARL are genetically similar to wild populations. PMID:17540076
Kim, Kyung Seok; French, B Wade; Sumerford, Douglas V; Sappington, Thomas W
Across the Northern hemisphere, managed honey bee colonies, Apis mellifera, are currently affected by abrupt depopulation during winter and many factors are suspected to be involved, either alone or in combination. Parasites and pathogens are considered as principal actors, in particular the ectoparasitic mite Varroa destructor, associated viruses and the microsporidian Nosema ceranae. Here we used long term monitoring of colonies and screening for eleven disease agents and genes involved in bee immunity and physiology to identify predictive markers of honeybee colony losses during winter. The data show that DWV, Nosema ceranae, Varroa destructor and Vitellogenin can be predictive markers for winter colony losses, but their predictive power strongly depends on the season. In particular, the data support that V. destructor is a key player for losses, arguably in line with its specific impact on the health of individual bees and colonies. PMID:22384162
Dainat, Benjamin; Evans, Jay D; Chen, Yan Ping; Gauthier, Laurent; Neumann, Peter
Across the Northern hemisphere, managed honey bee colonies, Apis mellifera, are currently affected by abrupt depopulation during winter and many factors are suspected to be involved, either alone or in combination. Parasites and pathogens are considered as principal actors, in particular the ectoparasitic mite Varroa destructor, associated viruses and the microsporidian Nosema ceranae. Here we used long term monitoring of colonies and screening for eleven disease agents and genes involved in bee immunity and physiology to identify predictive markers of honeybee colony losses during winter. The data show that DWV, Nosema ceranae, Varroa destructor and Vitellogenin can be predictive markers for winter colony losses, but their predictive power strongly depends on the season. In particular, the data support that V. destructor is a key player for losses, arguably in line with its specific impact on the health of individual bees and colonies.
Dainat, Benjamin; Evans, Jay D.; Chen, Yan Ping; Gauthier, Laurent; Neumann, Peter
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.
Cultures of Vibrio cholerae 01, biotype El Tor, from the current epidemic of cholera in the Western Hemisphere, and of the new V. cholerae serogroup O139, from the current outbreak in India and Bangladesh, revealed marked colonial heterogeneity when received by the authors. By comparison with reference colony types, using a stereoscope and transmitted oblique illumination, colonies of approximately 10 different degrees of opacity could be distinguished. In contrast, strains freshly isolated from patients and rapidly and carefully preserved were more homogeneous although still differentiable by this technique. These (and older) observations prompted the questions: (1) why is a V. cholerae colony opaque or translucent? and (2) what benefit is it to the vibrios to vary their colonial appearance? The observed changes in colonial opacity, which are reversible, are sometimes (rarely) accompanied by changes in virulence for infant rabbits and, more frequently, by other phenotypic variations including the ability to produce poly-beta-hydroxybutyrate inclusion bodies on glycerol-containing medium, the degree of encapsulation in 0139, changes in outer-membrane proteins, alteration in lipopolysaccharide structure, changes in expression of glycolytic pathways, and differences in ability to survive under adverse conditions. Colonial variations in choleragenic vibrios are phenotypically multifactorial. The genetic mechanisms(s) underlying the observed phenotypic changes remain to be defined. PMID:9025275
Finkelstein, R A; Boesman-Finkelstein, M; Sengupta, D K; Page, W J; Stanley, C M; Phillips, T E
Ants, as paradigm of social insects, have become a recurrent example of efficient problem solvers via self-organization. In spite of the simple behavior of each individual, the colony as a whole displays ``swarm intelligence:'' the organization of ant trails for foraging is a typical output of it. But conventional techniques of observation can hardly record the amount of data needed to get a detailed understanding of self-organization of ant swarms in the wild. Here we are presenting a measurement system intended to monitor ant activity in the field comprising massive data acquisition and high sensitivity. A central role is played by an infrared sensor devised specifically to monitor relevant parameters to the activity of ants through the exits of the nest, although other sensors detecting temperature and luminosity are added to the system. We study the characteristics of the activity sensor and its performance in the field. Finally, we present massive data measured at one exit of a nest of Atta insularis, an ant endemic to Cuba, to illustrate the potential of our system.
Noda, C.; Fernández, J.; Pérez-Penichet, C.; Altshuler, E.
Histocompatibility is the basis by which multicellular organisms of the same species distinguish self from nonself. 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-nonself and determines "graft" outcomes in this organism. This gene is significantly up-regulated in colonies poised to undergo fusion and/or rejection, is highly expressed in the vasculature, and is functionally linked to histocompatibility outcomes. These findings establish a platform for advancing the science of allorecognition. PMID:23888037
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
For counting of both colonies and plaques, there is a large number of applications including food, dairy, beverages, hygiene, environmental monitoring, water, toxicology, sterility testing, AMES testing, pharmaceuticals, paints, sterile fluids and fungal contamination. Recently, many researchers and developers have made efforts for this kind of systems. By investigation, some existing systems have some problems since they belong to a new technology product. One of the main problems is image acquisition. In order to acquire colony images with good quality, an illumination box was constructed as: the box includes front lightning and back lightning, which can be selected by users based on properties of colony dishes. With the illumination box, lightning can be uniform; colony dish can be put in the same place every time, which make image processing easy. A digital camera in the top of the box connected to a PC computer with a USB cable, all the camera functions are controlled by the computer.
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
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.
This paper uses the concepts of Disneyfication and Disneyization to discuss the (re)presentation of history at Disney’s American Adventure, Mount Vernon, Monticello, and Colonial Williamsburg. It is argued that these historical properties to varying degrees have adopted Disney principles. While the discussion focuses upon the Disney?like experiences of colonial America at these sites, the piece concludes with a comment on
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.
Recent losses in honey bee colonies are unusual in their severity, geographical distribution, and, in some cases, failure to present recognized characteristics of known disease. Domesticated honey bees face numerous pests and pathogens, tempting hypotheses that colony collapses arise from exposure to new or resurgent pathogens. Here we explore the incidence and abundance of currently known honey bee pathogens in colonies suffering from Colony Collapse Disorder (CCD), otherwise weak colonies, and strong colonies from across the United States. Although pathogen identities differed between the eastern and western United States, there was a greater incidence and abundance of pathogens in CCD colonies. Pathogen loads were highly covariant in CCD but not control hives, suggesting that CCD colonies rapidly become susceptible to a diverse set of pathogens, or that co-infections can act synergistically to produce the rapid depletion of workers that characterizes the disorder. We also tested workers from a CCD-free apiary to confirm that significant positive correlations among pathogen loads can develop at the level of individual bees and not merely as a secondary effect of CCD. This observation and other recent data highlight pathogen interactions as important components of bee disease. Finally, we used deep RNA sequencing to further characterize microbial diversity in CCD and non-CCD hives. We identified novel strains of the recently described Lake Sinai viruses (LSV) and found evidence of a shift in gut bacterial composition that may be a biomarker of CCD. The results are discussed with respect to host-parasite interactions and other environmental stressors of honey bees. PMID:22927991
Cornman, R Scott; Tarpy, David R; Chen, Yanping; Jeffreys, Lacey; Lopez, Dawn; Pettis, Jeffery S; vanEngelsdorp, Dennis; Evans, Jay D
The review briefs the history of the invention of the molecular colony techique, also known as a polony technology; applications\\u000a of this method to studies of the reactions between single RNA molecules, ultrasensitive diagnosis, gene cloning, and in vitro\\u000a screening, as well as the concepts of the origin of life that regard molecular colonies as a prototype of living organisms.
The evolutionary stability of cooperation and altruism in colonies of social insects requires that nestmates be to some extent\\u000a related. An efficient system of discrimination against non-nestmates protects the nest against unrelated conspecifics, which\\u000a might exploit or parasitize the colony. The co-occurrence of unrelated individuals in mature colonies therefore is a rare\\u000a event that deserves more attention. Here, we report
Comparisons across bird species have indicated that those more exposed to parasites and pathogens invest more in immunological defence, as measured by spleen size. We investigated how spleen volume varied with colony size, parasite load and an individual's colony-size history in the cliff swallow, Petrochelidon pyrrhonota, a colonial passerine bird of North America. We used a sample of over 1700 birds that had all died during a period of inclement weather in 1996. We experimentally manipulated ectoparasitism by fumigating nests in some colonies prior to the bad weather. Birds from parasite-free colonies had significantly smaller spleens than those from naturally infested sites; spleen volume did not differ between the sexes and did not vary with age. Mean spleen volume increased significantly with the colony size at a site prior to the bad weather in 1996 and at the site in 1995, both measures of colony size being indices of ectoparasitism at a site. An individual's history of breeding-colony size (defined as the average colony size it had occupied in years prior to 1996) had no association with its spleen size. The results are consistent with parasite-induced splenomegaly whenever birds are exposed to large numbers of ectoparasites. The results do not support spleen size as being a signal of differential life-history investment in immunological defence among individuals and thus run counter to interpretations from recent cross-species comparisons.
Access to the article is free, however registration and sign-in are required. Leprosy has been the scourge of humanity for thousands of years, yet we still know very little about the pathogenesis of this tragic disease. In his Perspective, Brophy explains exciting new findings (Rambukkana et al.) that reveal how the bacterium causing this disease, M. leprae, instigates demyelination of peripheral nerves without the help of the immune system, and subverts the attempts of myelinating Schwann cells to repair the damage.
Peter J. Brophy (University of Edinburgh;Department of Preclinical Veterinary Sciences)
Ant colony optimization (ACO) is a metaheuristic that takes inspiration from the foraging behaviour of a real ant colony to solve the optimization problem. This paper presents a multiple colony ant algorithm to solve the Job-shop Scheduling Problem with the objective that minimizes the makespan. In a multiple colony ant algorithm, ants cooperate to find good solutions by exchanging information
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
Social insect colonies invest in reproduction and growth, but how colonies achieve an adaptive allocation to these life-history characters remains an open question in social insect biology. Attempts to understand how a colony's investment in reproduction is shaped by the queen and the workers have proved complicated because of the potential for queen--worker conflict over the colony's investment in males
Manual counting of bacterial colony forming units (CFUs) on agar plates is laborious and error-prone. We therefore implemented a colony counting system with a novel segmentation algorithm to discriminate bacterial colonies from blood and other agar plates.A colony counter hardware was designed and a novel segmentation algorithm was written in MATLAB. In brief, pre-processing with Top-Hat-filtering to obtain a uniform background was followed by the segmentation step, during which the colony images were extracted from the blood agar and individual colonies were separated. A Bayes classifier was then applied to count the final number of bacterial colonies as some of the colonies could still be concatenated to form larger groups. To assess accuracy and performance of the colony counter, we tested automated colony counting of different agar plates with known CFU numbers of S. pneumoniae, P. aeruginosa and M. catarrhalis and showed excellent performance. PMID:22448267
Changes in host phenotype are often attributed to manipulation that enables parasites to complete trophic transmission cycles. We characterized changes in host phenotype in a colonial host–endoparasite system that lacks trophic transmission (the freshwater bryozoan Fredericella sultana and myxozoan parasite Tetracapsuloides bryosalmonae). We show that parasitism exerts opposing phenotypic effects at the colony and module levels. Thus, overt infection (the development of infectious spores in the host body cavity) was linked to a reduction in colony size and growth rate, while colony modules exhibited a form of gigantism. Larger modules may support larger parasite sacs and increase metabolite availability to the parasite. Host metabolic rates were lower in overtly infected relative to uninfected hosts that were not investing in propagule production. This suggests a role for direct resource competition and active parasite manipulation (castration) in driving the expression of the infected phenotype. The malformed offspring (statoblasts) of infected colonies had greatly reduced hatching success. Coupled with the severe reduction in statoblast production this suggests that vertical transmission is rare in overtly infected modules. We show that although the parasite can occasionally infect statoblasts during overt infections, no infections were detected in the surviving mature offspring, suggesting that during overt infections, horizontal transmission incurs a trade-off with vertical transmission. PMID:23965820
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.
1. Smooth, round, shiny, non-granular, and non-spreading colonies have been observed in cultures of virulent tubercle bacilli freshly isolated from eight human sources other than sputum. The classification of six of these strains as of human type was established by inoculation into rabbits and guinea pigs. 2. The 3 per cent NaOH or 6 per cent H2SO4 frequently used in the isolation of tubercle bacilli are definitely unfavorable to the development of smooth colonies. 3. It was observed that smooth colonies are produced in greater number when the pH of the medium (Corper's egg yolk-glycerine) is adjusted to a point near to but slightly on the acid side of neutral.
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.
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
Drug therapy during the Colonial and Revolutionary War period in America is discussed. Therapy in the 17th and 18th centuries remained largely symptomatic rather than curative. Treatment included such "depletion" measures as purging, sweating, bleeding, blistering and vomiting. Purgatives, emetics, opium, cinchona bark, camphor, potassium nitrate and mercury were among the most widely used drugs. European herbals, dispensatories and textbooks were used in the American colonies, and beginning in the early 18th century, British "patent medicines" were imported. During the Revolutionary War, the supply of drugs from Britain was cut off. The Continental Congress established laboratories and storehouses to serve the needs of the army. PMID:782235
The role of geophysics in early America is a fragmented and rarely told story. Its beginning predated the actual rise of America as a nation, and its development can be traced even through the years of the American Revolution. It seems appropriate to look back to these Colonial times to reflect, as part of science's input to the Bicentennial Year,
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
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
Through a close study of a rich set of demographic and economic statistics, students will see the development over 150 years of two similar yet divergent colonies (Virginia and Barbados). They will work through population, land use, and trade statistics with closely-guiding questions in order to find links between one set of numbers and another.
The unusual features of the Icarian Colony included the emphasis on equality in participation in the social organization by all age groups. The men, their wives, and their children all had a contribution to make through various roles. These roles included the positions of responsibility in the daily life of the group, in the governance of the Society, in the
|This article considers two related educational endeavors of the Massachusetts colony. The first is the colonists' efforts to pass their religious traditions to their children. The second is the effort of missionaries to spread the Christian faith to Native Americans. In both cases, the colonists wanted their children and the American Indians to…
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; Mondragón-Palomino, Octavio; Orozco-Fuentes, Sirio; Danino, Tal; Hasty, Jeff; Tsimring, Lev S.
|The United States revolution of 1776 is said to lose validity in light of Puerto Rico's colonial situation under American rule. The plight of the Puerto Rican people is compared to that of the Euro-American settlers under the thumb-screw of British imperialism. (Author/AM)|
Argues that attempts to institute proper and effective methods of educating non English speaking students cannot be reduced simply to issues of language, but rest on a full understanding of the ideological elements that generate and sustain linguistic, cultural, and racial discrimination, which represent vestiges of a colonial legacy in today's…
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
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…
The scarcity of data relative to the first importations of cattle into Colonial North America has lent obscurity to one of the most interesting phases of early American husbandry. In fact this paucity and incomplete- ness of information dealing with the introduction of cattle into what is now the United States of America has led many authors in the field
This essay examines the relationship between religion and the concept of nationhood in late colonial India. Religion was a crucial element in the formation of modern states in the early 20th century in South Asia. Different religious groups had different opinions about nation: Hindus and Muslims had different ideas of nationhood; even within the Hindu tradition, the Hindus themselves had
Protestant and Roman Catholic missions pioneered Western medicine and public health in much of Africa decades in advance of health services provided by colonial governments. A century later church-based hospitals and health care programs continue to account for 25% to 50% of available services in most African countries. In view of the important historical and continuing role of medical missions
Police forces in Nigeria have been variously described as corrupt, oppressive and subservient to the whims and caprices of the government of the day. This paper analyses the development of police forces in Nigeria since the era of British colonial domination in the country. Police corruption and repression in Nigeria is analyzed in the context of the wider political and
|Rejects the essentialist notion of the need to exclude children with disabilities from the school community, tracing the origin of disability segregation to the advent of western colonialism and demonstrating the symbiotic relationship between cultural and racial oppression and the oppression of people with disabilities. The paper strongly…
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
|This project is a unit of six lessons designed to study and understand the roles and expectations of women in the colonial period. The unit provides an historical perspective on those expectations, examines how both men and women viewed the sphere of women, and how enlightened thought on this topic began to emerge during this revolutionary time.…
This project is a unit of six lessons designed to study and understand the roles and expectations of women in the colonial period. The unit provides an historical perspective on those expectations, examines how both men and women viewed the sphere of women, and how enlightened thought on this topic began to emerge during this revolutionary time.…
When considering the nature of culture contact and colonialism it is as important to study the continuities in the host society, as it is to study the impositions made by incoming peoples. The diverse relationships between colonised and colonising societies are likely to be played out in aspects of material culture. This study examines Ntsweng and Phalatswe, two Tswana settlements
Andrew Reid; Alinah Segobye; Lowe Borjeson; Nonofo Mathibidi; Princess Sekgarametso
Ant colony algorithms are a group of heuristic optimization algorithms that have been inspired by ants foraging for food. In these algorithms there are some agents, the ants, that for finding the suitable solution, search the solution space. On the other hand, Learning Automata is an abstract model that can do finite actions. Each selected action is evaluated by a
Ant Colony Optimization is a constructive meta-heuristic that uses an analogue of ant trail pheromones to learn about good features of solutions. In this paper, using the difference equations as a tool of research, we propose the mathematical model of the distribution of pheromone at the classic double bridge experiment, explain the mathematical model of the pheromone function in the
The structure of cell colonies is governed by the interplay of many physical and biological factors, ranging from properties of surrounding media to cell-cell communication and gene expression in individual cells. The biomechanical interactions arising from the growth and division of individual cells in confined environments are ubiquitous, yet little work has focused on this fundamental aspect of colony formation. By combining experimental observations of growing monolayers of non-motile strain of bacteria Escherichia coli in a shallow microfluidic chemostat with discrete-element simulations and continuous theory, we demonstrate that expansion of a dense colony leads to rapid orientational alignment of rod-like cells. However, in larger colonies, anisotropic compression may lead to buckling instability which breaks perfect nematic order. Furthermore, we found that in shallow cavities feedback between cell growth and mobility in a confined environment leads to a novel cell streaming instability. Joint work with W. Mather, D. Volfson, O. Mondrag'on-Palomino, T. Danino, S. Cookson, and J. Hasty (UCSD) and D. Boyer, S. Orozco-Fuentes (UNAM, Mexico).
The United States revolution of 1776 is said to lose validity in light of Puerto Rico's colonial situation under American rule. The plight of the Puerto Rican people is compared to that of the Euro-American settlers under the thumb-screw of British imperialism. (Author/AM)
The dominant hypothesis in the literature that studies conflict is that poverty is the main cause of civil wars. We instead analyze the effect of institutions on civil war, controlling for income per capita. In our set up, institutions are endogenous and colonial origins affect civil wars through their legacy on institutions. Our results indicate that institutions, proxied by the
This essay focuses on the earliest British travel narratives to Tibet and on colonial culture's reception of Tibetan Buddhism. It addresses the related discourses of commerce and religion to show how the interplay of free?market ideology and Buddhist culture, at work in these travelogues, enlarged the boundaries of Britain's imagined community, while complicating the Romantic hegemonic construction of Hinduism.
The Jackson Laboratory Colony Management System (JCMS) is a software application for managing data and information related\\u000a to research mouse colonies, associated biospecimens, and experimental protocols. JCMS runs directly on computers that run\\u000a 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
Chuck J. Donnelly; Mike McFarland; Abigail Ames; Beth Sundberg; Dave Springer; Peter Blauth; Carol J. Bult
An automatic colony counter was tested extensively with colonies of two bacterial species, Serratia marcescens and Bacillus subtilis var. niger, grown on agar media. A stable relationship was established between machine counts and counts done visually by ...
Colonial National Historical Park was originally authorized as a national monument in 1930, and later established as a national historical park in 1936. The Park protects the historical units of Jamestown and Yorktown. In 1957, the Colonial Parkway was co...
C. N. Bentsen S. Costanzo T. Lookingbill T. J. B. Carruthers W. C. Dennison
fter September 11th, more than a few commenta- tors have claimed that what is needed around the world is a revived colonialism under America's hand. These commentators accordingly urge us to look to the British colonial empire for guidance: \\
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
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
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.
Bovine bone marrow granulocyte/macrophage colonies were cultured in vitro in methyl cellulose and in plasma clots using bovine endotoxin-stimulated serum as a source of colony stimulating activity. The endotoxin-stimulated serum was four times as potent as the control serum in the methyl cellulose cultures. No significant increase in the number of colony forming units was observed when bovine marrow cells were maintained in suspension cultures for various periods prior to plating in methyl cellulose. The percentage of glass/plastic adherent cells in bovine marrow cells was observed to be 43% +/- 12 (SD). Benzidine positive erythroid colonies appeared in plasma clot cultures on day 4 and disappeared by day 9. No second population of erythroid colonies appeared either as a function of time or as a function of erythropoietin concentration. The optimum erythropoietin concentration for bovine erythroid cultures was found to be 1.0 unit/mL. A significant difference was observed between animals in their marrow capacity to produce erythroid colonies in culture but no significant difference was observed within individual animals over a period of three months. Images Fig. 3.
Who needs to go to outer space to study alien beings when the oceans of our own planet abound with bizarre and unknown creatures? Many of them belong to sessile clonal and colonial groups, including sponges, hydroids, corals, octocorals, ascidians, bryozoans, and some polychaetes. Their life histories, in many ways unlike our own, are a challenge for biologists. Studying their ecology, behavior, and taxonomy means trying to “think like a colony” to understand the factors important in their lives. Until the 1980s, most marine ecologists ignored these difficult modular organisms. Plant ecologists showed them ways to deal with the two levels of asexually produced modules and genetic individuals, leading to a surge in research on the ecology of clonal and colonial marine invertebrates. Bryozoans make excellent model colonial animals. Their life histories range from ephemeral to perennial. Aspects of their lives such as growth, reproduction, partial mortality due to predation or fouling, and the behavior of both autozooids and polymorphs can be studied at the level of the colony, as well as that of the individual module, in living colonies and over time. PMID:21714171
|Focuses on an early twentieth century journal called "Oversea Education," designed to increase communication among British colonies, particularly for education, based on William Ormsby Gore's travels among the colonies. Describes Frank Ward's editorial work that championed the rights of colonial subjects to have better educational policy. (KDR)|
This paper presents a multi-ant colonies approach for clustering data that consists of some parallel and independent ant colonies and a queen ant agent. Each ant colony process takes different types of ants moving speed and different versions of the probability conversion function to generate various clustering results with an ant-based clustering algorithm. These results are sent to the queen
Behavioral plasticity in social insects is intriguing because colonies adjust to environmental change through the aggregated re- sponses of individuals. Without central control, colonies adjust num- bers of workers allocated to various tasks. Individual decisions are based on local information from the environment and other workers. This study examines how colonies of the seed-eating ant Pogono- myrmex barbatus adjust the
The paper presents the ant colony algorithm and its application for the path planning. Ant algorithms were designed on the base of the behaviour of real ant colonies. Real ants can always find the shortest way between the nest and the food so one of the most “natural” is the application of the ant colony algorithm in the path planning.
Legal historians have long emphasized the role courts played in promoting the development of a market society in colonial America. Indeed, judicial enforcement of debt agreements and other contractual obligations has been viewed as the central and most important aspect of government promotion of the nascent colonial economy. Nevertheless, there has been substantial disagreement about the extent of colonial economic
Cities and religious orders in colonial Latin America competed vigorously and often bitterly to acquire a university, but little is understood of the cultural impact of the university on cities, regions, or the colonial system. The university in the Spanish colonies derived its organization and traditions from the University of Salamanca, a…
|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…
This article serves as a foundation for understanding the earliest form of technical instruction in colonial America. It is a synthesis of historical studies that have addresses the edu- cation of indentured servants and apprentices in colonial America. It defines indentured servi- tude and contrasts it with apprenticeship—a form of indentured service. The paper addresses how indentured servitude in colonial
It is known that the zooplankter Daphnia induces colonies in the alga Scenedesmus. As Daphnia grazes on Scenedesmus, it has been postulated that colony formation represents an algal defense mechanism. This induction of Scenedesmus coenobia\\/colonies by Daphnia could be associated with a substance exuded by the animals that acts as a specific infochemical (kairomone) for Scenedesmus. However, the chemical nature
Demonstrates how the British Colonial Office employed public relations strategies as they administered the British colony of Northern Rhodesia before, during, and after World War II. Demonstrates how civil servants in London and colonial officials implemented public relations policies, strategies, and tactics on an ad hoc basis, covering political…
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
|Cities and religious orders in colonial Latin America competed vigorously and often bitterly to acquire a university, but little is understood of the cultural impact of the university on cities, regions, or the colonial system. The university in the Spanish colonies derived its organization and traditions from the University of Salamanca, a…
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
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.
Highfield, Andrea C.; El Nagar, Aliya; Mackinder, Luke C. M.; Noel, Laure M.-L. J.; Hall, Matthew J.; Martin, Stephen J.; Schroeder, Declan C.
Polymerase colony (polony) technology amplifies multiple individual DNA molecules within a thin acrylamide gel attached to a microscope slide. Each DNA molecule included in the reaction produces an immobilized colony of double-stranded DNA. We genotype these polonies by performing single base extensions with dye-labeled nucleotides, and we demonstrate the accurate quantitation of two allelic variants. We also show that polony technology can determine the phase, or haplotype, of two single- nucleotide polymorphisms (SNPs) by coamplifying distally located targets on a single chromosomal fragment. We correctly determine the genotype and phase of three different pairs of SNPs. In one case, the distance between the two SNPs is 45 kb, the largest distance achieved to date without separating the chromosomes by cloning or somatic cell fusion. The results indicate that polony genotyping and haplotyping may play an important role in understanding the structure of genetic variation.
Mitra, Robi D.; Butty, Vincent L.; Shendure, Jay; Williams, Benjamin R.; Housman, David E.; Church, George M.
INTRODUCTIONTo provide sufficient material for experimentation, a laboratory needs to expand and maintain a colony of planarians. It is crucial to keep a stable, healthy population of animals in a consistent environment to avoid inter-animal variability and modifier effects that can mask true phenotypes from experimental perturbation. In this protocol, we describe basic procedures for establishing and maintaining healthy colonies of Dugesia japonica, Schmidtea mediterranea, and Girardia tigrina (commonly found in the wild and commercially available in the United States). Although the recommendations are based on our optimization of conditions for G. tigrina, many of the procedures (such as food preparation and feeding strategy) can be applied to other species. For best results, the culture water must be carefully monitored and adjusted for each species. PMID:21356691
Abstract . Four lines of evidence indicate that evening bats, Nycticeius humeralis, at nursery colonies in northern,Missouri,transfer,information,by following,each,other,to feeding,and,roosting,sites . (1) Daily estimates,of insect,density,from,five,automated,suction,traps,showed,that,common,prey,in evening,bat faecal samples, small beetles and flies, occur in rich patches that persist for several days . Bats apparently respond,to prey,density,and,variability,because,these,variables,independently,predict,the,number,of trips and,capture,success,of foraging,bats,. (2) Videotape,records,of the,time,and,weight,of bats,arriving,and departing,from,a colony,indicated,that,adult,females,leave,within,10 s of each,other,on second,and subsequent,foraging,trips,more,often,than,expected,within,a night
An artificial ant sleeping model (ASM) and adaptive artificial ants clustering algorithm (A 4C) are presented to resolve the clustering problem in data mining by simulating the behaviors of gregarious ant colonies. In the ASM mode, each data is represented by an agent. The agents' environment is a two-dimensional grid. In A 4C, the agents can be formed into high-quality
\\u000a The Ant Colony Optimization (ACO) technique was inspired by the ants’ behavior throughout their exploration for food. In nature,\\u000a ants wander randomly, seeking for food. After succeeding, they return to their nest. During their move, they lay down pheromone\\u000a that forms an evaporating chemical path. Other ants that locate this trail, follow it and reinforce it, since they also lay
Ioannis Michelakos; Nikolaos Mallios; Elpiniki Papageorgiou; Michael Vassilakopoulos
Apis mellifera is used for honeybee keeping all over Turkey. Recently, honeybees have been suddenly disappearing for no apparent reason. It is presumed that some viral and parasitic honeybee pathogens are responsible for this. No medical research has been conducted to determine the pathologic causes of the sudden die-off of the honeybee colonies in Turkey as yet. This is of urgent importance for future of the honeybee industry. PMID:18985587
\\u000a We present a model for the travelling salesman problem (TSP) solved using the ant colony optimisation (ACO), a bio-inspired\\u000a mechanism that helps speed up the search for a solution and that can be applied to many other problems. The natural complexity\\u000a of the TSP combined with the self-organisation and emergent behaviours that result from the application of the ACO make
Lucio Mauro Duarte; Luciana Foss; Flávio Rech Wagner; Tales Heimfarth
Summary: A major threat to eusocial colonies is predation (Starr, 1990) since these colonies place their entire reproductive investment into a single nest (Hansell, 1996). The vertebrate predator is probably the most destructive type of predator in that it can remove the entire nest and thereby destroy all of the investment made by the colony.¶ In this study I considered
An Astronomy Resource Center, funded by IDEA grant ED 90003.01-94A, has recently been set up at Sommers-Bausch Observatory on the University of Colorado at Boulder campus. The purpose of the Astronomy Resource center is to foster close ties between the University's research and teaching staff (including graduate students) and local schools. Graduate students and professors are matched with teacher requests on specific topics, and come into classrooms of local schools as well as providing general resource assistance. University personnel are usually asked to put in a minimal amount of time from which the students greatly benefit. Occasionally, however, teachers have more ambitious projects in mind. One such link between a local elementary school teacher and a graduate student has led to the development of an 8 week long curriculum centered around planning a Mars colony, and ending with the previously existing MarsVille project developed by the Challenger Center for Space Science Education. Tailor-made for a gifted and talented program composed of students from grades 4-6, the curriculum is designed to teach a variety of concepts and skills with an emphasis on planetary astronomy. Although the Mars colony material is designed to utilize University resources and extensive classroom time with the graduate student involved, neither is essential to the program. In addition to a presentation of the Mars colony curriculum, a discussion of the experiences and difficulties of putting together the program will be discussed.
We report a novel morphological transition in a Bacillus subtilis colony initially growing under ambient conditions, after ultraviolet radiation exposure. The bacteria in the central regions of the colonies are observed to migrate towards the colony edge forming a ring during uniform spatial exposure. When the radiation is switched off, the colonies were observed to grow both inward into the evacuated regions as well as outward indicating that the pattern is not formed due to depletion of nutrients at the center of the colony. We also propose a reaction-diffusion model in which waste-limited chemotaxis initiated by the UV radiation leads to the observed phenomenology.
Delprato, Anna M.; Samadani, Azadeh; Kudrolli, A.; Tsimring, L. S.
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 of chemical agent) signalling, collective activation and deactivation of genes and even exchange of genetic material. Utilizing these capabilities, the bacterial colonies develop complex spatio-temporal patterns in response to adverse growth conditions. We present a wealth of beautiful patterns formed during colonial development of various bacterial strains and for different environmental conditions. Invoking ideas from pattern formation in non-living systems and using generic modelling we are able to reveal novel bacterial strategies which account for the salient features of the evolved patterns. Using the models, we demonstrate how bacterial communication leads to colonial self-organization that can only be achieved via cooperative behaviour of the cells. It can be viewed as the action of a singular feedback between the microscopic level (the individual cells) and the macroscopic level (the colony) in the determination of the emerging patterns.
The queen's role in colony activity integration in small post-emergence colonies of Polistes fuscatus was investigated in the field. We continuously recorded the behaviors of all wasps in (1) undisturbed colonies, (2) colonies from which the queen had been removed, (3) colonies from which a single worker had been removed, (4) colonies with a cooled, relatively inactive queen, and (5)
This paper traces an intricate path connecting racial fantasy, aesthetic judgment, and the larger cultural problem of inter-subjective recognition. In particular, the author examines the theme of fetishism, both sexual and racial, in a Western historical, colonial context, in order to unravel a set of disturbances that cohere around the racial fetish then and now. Taking the figure of an entertainment icon of the 1920s, Josephine Baker, as a case study, the author shows how the imagination of the colonizing white male was both articulated and disrupted by Baker as a ready-made representation of the cultural, racial, and sexual other. PMID:16482962
A begger's colony where a neuropsychiatric extension clinic is being run by NIMHANS, Bangalore, was selected for this study wherein 78 neuropsychiatrically ill inmates and 85 well ones were examined and diagnosed as per I.C.D.-9 and followed up on treatment. A period prevalence of 131.09/1000 serious neuropsychiatric morbidity was found with psychoses, mental retardation and epilepsy being more frequent than in general population studies. Findings in this study, point towards a need for reaching neuropsychiatric care to this section of society, and also confirm the association of certain social factors with serious morbidity. PMID:21927125
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.
Trathan, Philip N.; Fretwell, Peter T.; Stonehouse, Bernard
Here we describe a new phenomenon, entombed pollen, which is highly associated with increased colony mortality. Entombed pollen appears as sunken, wax-covered cells amidst “normal”, uncapped cells of stored pollen, and the pollen contained within these cells is brick red in color. There appears to b...
Body mass shapes processes from cell metabolism to community dynamics. Little is known, however, about how the average body mass of individuals varies among ecological communities. Ants alter colony mass by independently changing worker mass and\\/or worker number. In a survey of 49 ecosystems from tundra to tropical rainforest, average worker mass and worker number were uncorrelated (rs = 0.2,
This paper explores the relationships between landscape and power, colonialism and its aftermaths, and state territoriality and its contestation, in the work of two popular Northwest Coast landscape painters: Emily Carr and Lawrence Paul Yuxweluptun. The work of both artists is explored in terms of their representation of relations between indigenous peoples, physical landscapes, state power, and modernity, and in
Ecologists use stable isotopes to infer diets and trophic levels of animals in food webs, yet some assumptions underlying these inferences have not been thoroughly tested. We used laboratory-reared colonies of Solenopsis invicta Buren (Formicidae: Solenopsidini) to test the effects of metamorphosis,...
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…
In this paper I outline a brief period in the history of the British Empire, during which colonial lunatic asylum policy began to be formulated. I begin with a scandal that erupted in Jamaica and suggest that this set in motion processes that led to critical changes in asylum administration. The first of these processes was an audit of hospitals and asylums in the colonies. The results of the audit and the policy that emerged from it marked the beginning of systematic regulation of lunatic asylum practice across the British Empire. It revealed a formulation of policy that was intended to cut across the self-governing regimes that had up to this point been allowed to evolve. Drawing on the work of Michel Foucault and Nikolas Rose, I argue that the policy and the practices associated with it contribute to an understanding of the emergence of the psy-sciences in colonial settings. They illustrate the establishment of a panoptic gaze on previously neglected insane spaces. Systematic surveillance constituted government at a distance and made colonial lunacy administration a governable discursive space. The regulation of the medical officers, lunatic attendants, and hospital boards began the process of creating a professional psychiatric workforce. I conclude with a discussion of the implications and the mixed impact of this policy change for the mentally ill across the empire, over the ensuing decades. PMID:20533769
We investigated the phenomenon of activity cycles in ants, taking into account the spatial structure of colonies. In our study species, Leptothorax acervorum, there are two spatially segregated groups in the nest. We developed a model that considers the two groups as coupled oscillators which can produce synchronized activity. By investigating the effects of noise on the model system we predicted how the return of foragers affects activity cycles in ant colonies. We tested these predictions empirically by comparing the activity of colonies under two conditions: when foragers are and are not allowed to return to the nest. The activity of the whole colony and of each group within the colony was studied using image analysis. This allowed us to reveal the spatial pattern of activity wave propagation in ant colonies for the first time.
Boi, S.; Couzin, I. D.; Buono, N. Del; Franks, N. R.; Britton, N. F.
Using computational modeling, we design colonies of biomimetic microcapsules that exploit chemical mechanisms to communicate and alter their local environment. As a result, these synthetic objects can self-organize into various autonomously moving structures and exhibit ant-like tracking behavior. In the simulations, signaling microcapsules release agonist particles, whereas target microcapsules release antagonist particles and the permeabilities of both capsule types depend on the local particle concentration in the surrounding solution. Additionally, the released nanoscopic particles can bind to the underlying substrate and thereby create adhesion gradients that propel the microcapsules to move. Hydrodynamic interactions and the feedback mechanism provided by the dissolved particles are both necessary to achieve the collective dynamics exhibited by these colonies. Our model provides a platform for integrating both the spatial and temporal behavior of assemblies of “artificial cells,” and allows us to design a rich variety of structures capable of exhibiting complex, cooperative behavior. Due to the cell-like attributes of polymeric microcapsules and polymersomes, material systems are available for realizing our predictions.
Kolmakov, German V.; Yashin, Victor V.; Levitan, Steven P.; Balazs, Anna C.
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
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.
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.
Four different colony morphologies were produced by Flavobacterium columnare strains on Shieh agar plate cultures: rhizoid and flat (type 1), non-rhizoid and hard (type 2), round and soft (type 3), and irregularly shaped and soft (type 4). Colonies produced on AO agar differed from these to some extent. The colony types formed on Shieh agar were studied according to molecular characteristics [Amplified Fragment Length Polymorphism (AFLP), Automated Ribosomal Intergenic Spacer Analysis (ARISA), and whole cell protein SDS-PAGE profiles], virulence on rainbow trout fingerlings, and adhesion on polystyrene and fish gills. There were no molecular differences between colony types within one strain. Type 2 was the most adherent on polystyrene, but type 1 was the most virulent. Adhesion of F. columnare strains used in this study was not connected to virulence. From fish infected with colony type 1, three colony types (types 1, 2 and 4) were isolated. Contrary to previous studies, our results suggest that strong adhesion capacity may not be the main virulence factor of F. columnare. Colony morphology change might be caused by phase variation, and different colony types isolated from infected fish may indicate different roles of the colony morphologies in the infection process of columnaris disease. PMID:18984035
Kunttu, Heidi M T; Suomalainen, Lotta-Riina; Jokinen, E Ilmari; Valtonen, E Tellervo
Redox chemistry, involving the transfer of electrons and hydrogen atoms, is central to energy conversion in respiration, and the control of gene expression by redox state commonly occurs in bacteria, allowing rapid responses to environmental changes, for instance, in the food supply. Colonial metazoans often encrust surfaces over which the food supply varies in time or space; hence, in these organisms, redox control of the development of feeding structures and gastrovascular connections could be similarly adaptive, allowing colonies to adjust the timing and spacing of structures in response to a variable food supply. To investigate the possibility of redox control of colony development, the redox states of hydractiniid hydroid colonies were manipulated experimentally. As in many colonial animals, hydractiniid hydroids display a range of morphological variation from sheet-like forms (i.e. closely spaced polyps with high rates of stolon branching) to runner-like forms (i. e. widely spaced polyps with low rates of stolon branching). In the runner-like Podocoryna carnea, azide, a blocker of the electron transport chain, and dinitrophenol, an uncoupler of oxidative phosphorylation, diminished the largely polyp-driven gastrovascular flow to a similar extent. Measures of the redox state of the polyp epitheliomuscular cells using the fluorescence of NAD(P)H suggest that azide shifts the redox state in the direction of reduction, while dinitrophenol shifts the redox state in the direction of oxidation. Colony development corresponds to redox state in that azide-treated colonies were more runner-like, while dinitrophenol-treated colonies were more sheet-like. Nevertheless, the functional role of polyps in feeding and generating gastrovascular flow probably contributed to a trade-off between polyp number and size such that azide-treated colonies had few large polyps, while dinitrophenol-treated colonies had many small polyps. Regardless of the treatment, P. carnea colonies developed to maturity and produced swimming medusae in the normal fashion. In the sheet-like Hydractinia symbiolongicarpus, treatment with azide resulted in complete suppression of the development of both the stolonal mat and the blastostyles, the reproductive polyps. Azide-treated H. symbiolongicarpus colonies therefore developed in a juvenilized, runner-like manner and much resembled colonies of P. carnea. Following cessation of azide treatment in H. symbiolongicarpus, normal colony development ensued, and both a stolonal mat and blastostyles formed. In both hydroid species, relative oxidization favors sheet-like growth, while relative reduction favors runner-like growth. Since feeding triggers strong contractions of polyp epitheliomuscular cells and results in relative oxidation, this experimental evidence supports the hypothesis of adaptive redox control of colony development and evolution. PMID:10574731
The evaluation of new drug treatments and combination treatments for gliomas and other cancers requires a robust means to interrogate wide dose ranges and varying times of drug exposure without stain-inactivation of the cells (colonies). To this end, we developed a 3-dimensional (3D) colony formation assay that makes use of GelCount technology, a new cell colony counter for gels and soft agars. We used U251MG, SNB19, and LNZ308 glioma cell lines and MiaPaCa pancreas adenocarcinoma and SW480 colon adenocarcinoma cell lines. Colonies were grown in a two-tiered agarose that had 0.7% agarose on the bottom and 0.3% agarose on top. We then studied the effects of DFMO, carboplatin, and SAHA over a 3-log dose range and over multiple days of drug exposure. Using GelCount we approximated the area under the curve (AUC) of colony volumes as the sum of colony volumes (microm2xOD) in each plate to calculate IC50 values. Adenocarcinoma colonies were recognized by GelCount scanning at 3-4 days, while it took 6-7 days to detect glioma colonies. The growth rate of MiaPaCa and SW480 cells was rapid, with 100 colonies counted in 5-6 days; glioma cells grew more slowly, with 100 colonies counted in 9-10 days. Reliable log dose versus AUC curves were observed for all drugs studied. In conclusion, the GelCount method that we describe is more quantitative than traditional colony assays and allows precise study of drug effects with respect to both dose and time of exposure using fewer culture plates. PMID:18642971
Kajiwara, Yoshinori; Panchabhai, Sonali; Levin, Victor A
Populations of ants and other social insects self-organize and develop 'emergent' properties through stigmergy in which individual ants communicate with one another via chemical trails of pheromones that attract or repulse other ants. In this way, sophisticated properties and functions develop. Under appropriate conditions, in vitro microtubule preparations, initially comprised of only tubulin and GTP, behave in a similar manner. They self-organize and develop other higher-level emergent phenomena by a process where individual microtubules are coupled together by the chemical trails they produce by their own reactive growing and shrinking. This behaviour is described and compared with the behaviour of ant colonies. Viewing microtubules as populations of molecular ants may provide new insights as to how the cytoskeleton may spontaneously develop high-level functions. It is plausible that such processes occur during the early stages of embryogenesis and in cells. PMID:16968217
MACS-VRPTW, an Ant Colony Optimization based approach useful to solve vehicle routing problems with time windows is presented. MACS-VRPTW is organized with a hierarchy of artificial ant colonies designed to successively optimize a multiple objective function: the first colony minimizes the number of vehicles while the second colony minimizes the traveled distances. Cooperation between colonies is performed by exchanging information
Luca Maria Gambardella; E. Taillard; Giovanni Agazzi
The reproductive success of colonially breeding species depends in part upon a trade-off between the benefit of a dilution effect against nestling predation within larger colonies and colony conspicuousness. However, there may be no net survivorship benefit of dilution if smaller colonies are sufficiently inconspicuous. This raises the question about how the size distribution of breeding colonies on a landscape
The resource-constrained project scheduling problem is a typical combinatorial optimization problem. An ant algorithm with dual ant colonies is proposed to improve the effective allocation of project resources. The algorithm adaptively adjusts resource allocation according to the pheromone updated by artificial ants employed to search for feasible schedules. Two separate ant colonies are employed. The forward scheduling technique is applied
This work presents a multi-objective optimization method based on the artificial bee colony, called the MOABC, for optimizing problems with multiple objectives. The MOABC uses a grid-based approach to adaptively assess the Pareto front maintained in an external archive. The external archive is used to control the flying behaviours of the individuals and structuring the bee colony. The employed bees
|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…
Abstract: this paper we propose a new approachtosolve bi-criterionoptimization problems with ant algorithms where several colonies of antscooperate innding good solutions. Weintroduce two methods for cooperationbetween the colonies and compare them with a multistart antalgorithm that corresponds to the case of no cooperation. Heterogeneouscolonies are used in the algorithm, i.e. the ants dier in their preferencesbetween the two criteria. Every
The introduction of the concept of swarm intelligence into ant colony optimization (ACO) algorithms has shown the rich possibilities of self-organization when dealing with difficult optimization. Indeed, the inherent flexibility and efficiency of ACO algorithms proved to be advantageous for difficult dynamic discrete problems, e.g. routing in telecommunication networks. Moreover, we believe that ant colony algorithms can be efficient for
Ant colony algorithms are a class of metaheuristics which are inspired from the behavior of real ants. The original idea consisted in simulating the stigmergic communication, therefore these algorithms are considered as a form of adaptive memory programming. A new formalization is proposed for the design of ant colony algorithms, introducing the biological notions of heterarchy and communication channels. We
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:
To settle the contradictory between convergence speed and precocity and stagnation in ant colony algorithm, an adaptive ant colony algorithm, which is based on the equilibrium of the ant distribution, is presented. By dynamically adjusting the influence of each ant to the trail information updating and the selected probabilities of the paths according to the equilibrium of the ant distribution,
Ant colony optimization (ACO) is a cooperative, population-based technique for optimization. Ant algorithms were designed on the base of the behavior of real ant colonies. Real ants can always find the shortest way between the nest and food source, using the environment as the communication tool, named stigmergy. In this paper we focus precisely on the process of finding an
Ant colony optimization (ACO) is typically used to search paths through graphs. The concept is based on simulating the behavior of ants in finding paths from the colony to food. Its searching mechanism is applicable for optimizing electric circuits with components, like resistors and capacitors, available in discrete values. However, power electronic circuits (PECs) generally consist of components, like inductors,
Jun Zhang; Henry Shu-Hung Chung; Alan Wai-Lun Lo; Tao Huang
Ant colony optimization (ACO) is typically used to search paths through graphs. The concept is based on simulating the behavior of ants in finding paths from the colony to food. Its searching mechanism is applicable for optimizing electric circuits with components, like resistors and capacitors, available in discrete values. In this paper, an extended ACO (eACO) that can search the
Employing the emergency number 911 as a device to open onto two continents of governance – one ‘hot’ the other ‘cold’, one binary, the other the disaggregation of the binary – this paper shows that colonial governmentality is marked by a paradoxical combination of the two. Moreover, it argues that colonial governmentality is the progenitor of this form of governance
|To explore racial attitudes from the colonial period of the United States, a study examined advertising practices regarding announcements dealing with black slaves in colonial newspapers in Massachusetts, New York, Pennsylvania, Maryland, Virginia, and South Carolina. Careful scrutiny revealed no relationship between the editorial stance of a…
The controlled use of a continuous power supply for robots of a colony is presented. This work builds on previous work where capacitors were used as an onboard power supply, and where robots with metallic probes were charged at a power station. An onboard controller was implemented to direct the hexapod colony robot behavior according to its power supply status.
To explore racial attitudes from the colonial period of the United States, a study examined advertising practices regarding announcements dealing with black slaves in colonial newspapers in Massachusetts, New York, Pennsylvania, Maryland, Virginia, and South Carolina. Careful scrutiny revealed no relationship between the editorial stance of a…
The article addresses the issues of cultural and archival historical representations as they are presented in Danish journalism about historical events taking place in the former colonies of Denmark, the current United States' Virgin Islands (USVI). The (post)colonial relationship between Denmark and USVI has been overlooked by Danish and 'western'-based scholars for quite some time. The article presents the case
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
Trade unionism and politics are closely related in many developing countries, but they appear to be especially intimate in those countries which have recently gained their political independence from colonial rule. In such countries, nationalist movements were often built on a trade union base during the recent colonial period and continued to share common leadership and constituencies after independence. Consequently,
This article serves as a foundation for understanding the earliest form of technical instruction in colonial America. It is a synthesis of historical studies that have addresses the education of indentured servants and apprentices in colonial America. It defines indentured servitude and contrasts it with apprenticeship--a form of indentured…
Football, one of the central components of twentieth-century Bengali popular culture, has generally been neglected by historians as unworthy of serious academic enquiry. This article examines the way in which football as a societal mirror reflected the articulation of race and nation in colonial Calcutta in a period of clearest nationalist upsurge against colonial rule. It attempts to explain how
Colonial mentality is a term used widely by ethnic studies scholars and by the Filipino American community to refer to a form of internalized oppression among Filipinos and Filipino Americans. The authors propose that colonial mentality is a construct that is central to the understanding of the psychology of contemporary Filipino Americans. Drawing on larger scholarship from postcolonial studies and
|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.|
This research applies the meta-heuristic method of ant colony optimization (ACO) to an established set of vehicle routing problems (VRP). The procedure simulates the decision-making processes of ant colonies as they forage for food and is similar to other adaptive learning and artificial intelligence techniques such as Tabu Search, Simulated Annealing and Genetic Algorithms. Modifications are made to the ACO
Abstract This research applies the meta-heuristic method of ant colony optimization (ACO) to an established set of vehicle routing problems (VRP). The procedure simulates the decision-making processes of ant colonies as they forage for food and is similar to other adaptive learning and artificial intelligence techniques such as Tabu Search, Simulated Annealing and Genetic Algorithms. Modifications are made to the
|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…
The Transatlantic Constitution makes a major impact on the way we see the legacy of the colonial period and the later federal relationship that continues to affect us today. Mary Sarah Bilder presents an intensive examination of the structure and functioning of the legal relationship across the Atlantic, between the people of a colony and the legal metropolis in London.
During the nineteenth century, an artistic trend spread across Europe. As urban centers housed the majority of professional artists, individuals and groups relocated to remote, bucolic areas to form art colonies. Artist colonies are typically defined as a group of artists, generally painters, writers, and composers who worked and lived as a community for a certain period of time. Artists
Examination of genotypes of female-pup nursing pairs taken from large maternity colonies of the Mexican free-tailed bat in Texas demonstrates that nursing is nonrandom and selective along genetic (kinship) lines. This is contrary to previous reports that nursing in these colonies is indiscriminate. Although nursing is nonrandom, an estimated 17 percent of the females sampled were nursing pups that could
The king penguin, Aptenodytes patagonicus, breeds without a nest in colonies of several thousands of birds. To be fed, the chick must recognize the parents in a particularly noisy environment using only vocal cues. The call an adult makes when seeking the chick is emitted at a high amplitude level. Nevertheless, it is transmitted in a colonial context involving the
Constructing Mexico City: Colonial Conflicts over Culture, Space, and Authority examines the spatial, material, and cultural dimensions of life in eighteenth-century Mexico City, through programs that colonial leaders created to renovate and reshape urban environments. Focusing particularly on the administration of Viceroy Juan Vicente de Güemes Pacheco y Padilla, the second count of Revillagigedo (1789-1794), this book considers how the
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
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.
One commonly observed phenomena about taxation in Africa are regional differences and the fact that southern African countries have higher levels of shares of taxation in GDP. This article argues that the major source of differences in ‘tax effort’ is the colonial histories of various countries. Using standard measures of ‘tax effort in a panel data framework and dividing colonial
|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…
Physogastric queens of Melipona marginata were removed from their colonies in order to verify the acceptance of a new queen by workers. Colony strength was evaluated according to queen oviposition rate and comb diameters. Replacement was observed seven times. Its occurrence and speed related positively to colony strength, independently of queen's age. In weak colonies, queen replacement was observed only once, following colony population increase that occurred after introduction of combs from another colony. Worker oviposition after queen removal was observed three times: in a strong colony with virgin queens and males, and in two of the weak colonies. In the first two or three days of new queen oviposition, during which most of the eggs were eaten by the queen, worker oviposition preceded almost all provisioning and oviposition processes (POPs). After this period, worker oviposition decreased until it reached around 25% of the POPs. Daily oviposition rate of young queens decreased or was even interrupted by hatching of their first brood. PMID:16341425
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
Our aim was to test the existence of Gestalt colony odour in Camponotus fellah. We isolated individual workers to prevent trophallaxis, allogrooming and body contact. After 20 days, the cuticular hydrocarbon profile of the isolated ants diverged from that of the parent colony. Moreover, each isolated individual had its own specific blend. This procedure showed that after about 20 days
Raphael Boulay; Abraham Hefetz; Victoria Soroker; Alain Lenoir
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...
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
Jeremey Stoddard's article in this issue, "Toward a Virtual Field Trip Model for the Social Studies," describes his analysis of the Colonial Williamsburg Electronic Field Trip and a conceptual model for developing meaningful and successful electronic or virtual field trips. In an effort to contextualize the Colonial Williamsburg Electronic Field…
Summary. We continue the investigation of P colonies introduced in (7), a class of abstract computing devices composed of independent agents, acting and evolving in a shared environment. We decrease the number of agents needed to computational completeness of P colonies with one and two objects inside each agent, respectively, owing some special restrictions to the type of programs. We
We study two very simple variants of P colonies: systems with only one object inside the cells, and systems with insertion-deletion programs, so called P colonies with senders and consumers. We show that both of these extremely simple types of systems are able to compute any recursively enumerable set of vectors of
Lucie Ciencialová; Erzsébet Csuhaj-Varjú; Alica Kelemenová; György Vaszil
The spectacular success of eusocial insects can be attributed to their sophisticated cooperation, yet cooperation is conspicuously absent during colony foundation when queens are alone. Selection against this solitary stage has led to a dramatically different strategy in thousands of eusocial insect species in which colonies are started by groups of nestmates and the benefits of sociality are retained continuously. Dependent colony foundation (DCF) evolved recurrently multiple times across the ants, bees, and wasps, though its prevalence in termites remains unclear. We review adaptations at both the colony level (reproductive investment shifts from sexuals to workers) and the individual level (wingless queens evolve in ants), and other consequences for life history (invasiveness, parasite transmission). Although few studies have focused on DCF, the accumulated data from anecdotal reports, supported by indirect information including morphology, population genetics, and colony demographics, make it clear that this strategy is more diverse and widespread than is usually recognized. PMID:22934981
Cronin, Adam L; Molet, Mathieu; Doums, Claudie; Monnin, Thibaud; Peeters, Christian
In microbial ecology, accurate identification based on morphotype is often impossible, so the assumption is often made that colonies of the same morphotype represent the same species or biotype. This study examines the validity of using colony morphology as the selection criterion for calculating ecological indices of the diversity and equitability of recoverable microbial communities. Isolates within sets of microbial colonies were very similar in terms of colony morphology, microscopic appearance, resistance to metals, and response to API-rapid-NFT tests. Resistance to antibiotics was variable within sets. Fatty acid methyl ester (FAME) analysis distinguished between isolates of the same species or biotype. However, isolates belonging to the same biotype can be selected by morhotype. The researchers conclude colony morphology can provide an accurate basis on which to define recoverable diversity.
Haldeman, D.L.; Amy, P.S. (Univ. of Nevada, Las Vegas (United States))
At the heart of most colonial states lay a contradiction. On the one hand, colonial state institutions defined themselves in opposition to indigenous networks of power associated with the pre-colonial period, whether based on ethnicity, tribal kinship or religious affiliation. On the other hand, few colonial states had sufficient bureaucratic substance to operate separately of indigenous society. This paper suggests
It is concluded that colony-forming cells derived from normal marrow are not capable of indefinite proliferation when they are subjected to the pressure of repeated transplantation. Cells with colony-forming ability found within spleen colonies cannot be ...
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We re-investigated the behavior of hemocytes during the non-fusion (rejection) reaction between genetically incompatible colonies of the ascidian Botryllus schlosseri. In the course of the reaction, hemocytes - mainly morula cells - crowd inside the blind ends of marginal vascular vessels (known as ampullae) of the colonial leading edge (LE) facing the foreign colony which suggests the occurrence of chemotactic attraction of circulating hemocytes towards the ampullar lumen. Then, cells migrate, through the ampullar tips, into the partially fused tunics and contribute to the formation of the necrotic spots along the contact borders which characterize the reaction. Studies on histological sections clearly indicate that, although morula cell concentration is always higher in ampullae of the LE than in those of the lateral (L) part of the colony, their frequency significantly increases in LE ampullae of rejecting colonies with respect to LE ampullae of both fusing and isolated colonies. In addition, in vitro chemotaxis experiments demonstrated that blood plasma from incompatible colonies can stimulate morula cell migration through polycarbonate filters and this passage is inhibited by antibodies raised against mammalian pro-inflammatory cytokines. The possible nature and role of molecules recognized by anti-cytokine antibodies in hemocyte migration are discussed. PMID:16962802
Our aim was to test the existence of Gestalt colony odour in Camponotus fellah. We isolated individual workers to prevent trophallaxis, allogrooming and body contact. After 20 days, the cuticular hydrocarbon profile of the isolated ants diverged from that of the parent colony. Moreover, each isolated individual had its own specific blend. This procedure showed that after about 20 days of isolation there was a turnover of the colony odour, revealing the genetically expressed hydrocarbon profile of each individual. It also showed that the cuticular hydrocarbon profile is polymorphic, and that its homogeneity within a colony is maintained by frequent exchanges of hydrocarbons between workers. Behavioural observations of resident workers, in their nest, towards nestmates reintroduced after isolation indicated that a short isolation period (3-5 days), which induced a minor change in hydrocarbon profile, provoked frequent trophallactic solicitations. These were likely to permit the isolated ants to readjust their hydrocarbon profile to that of the ants in the mother colony. Longer isolation periods (20-40 days) induced a greater change in hydrocarbon profile and made the residents intolerant towards their introduced nestmates. Therefore, our results clearly support the existence of a Gestalt colony odour in C. fellah. They also show that since individual hydrocarbon production is dynamic, workers are obliged to exchange hydrocarbons continually (mainly by trophallaxis) in order to be in the Gestalt, and properly integrate into the colony. Copyright 2000 The Association for the Study of Animal Behaviour. PMID:10877891
Ceramic shards found in Spanish Colonial missions in Texas consist of broken remnants of wares either brought from Mexico or manufactured locally by 18th century Native Americans. A few are thought to be of European or Asian manufacture, but these consist of only a few percent of the ceramic assemblages available for study now. Certain types of ceramics are consistently found in these sites, including local Native American wares and Mexican slipped or glazed wares. In addition, undecorated lead-glazed coarse earthenwares occur in great frequency, but their place of origin is unknown. Speculation has been that these lead-glazed wares, which range in color from yellow to olive-green and occur in both coiled and wheel-thrown constructions, were locally made by Native Americans using Spanish technology or that they were imported from Mexico. Compositional analysis of these wares was undertaken to clarify their source of manufacture. The sample included 102 ceramics from four Texas mission sites: Mission San Lorenzo de la Santa Cruz in Real County, Mission San Juan Capistrano in Bexar County, Mission Rosario in Goliad County, and Mission Dolores de los Ais in San Augustine County. A larger goal of the study was to examine the supply system to these well-dispersed mission sites and how it was affected by Spain`s economic climate during the l8th century.
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
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.
Astronomical expeditions during the colonial period had a political and national significance also. Measuring the earth and mapping the sky were activities worthy of powerful and power- seeking nations. Such was the sanctity of global astronomical activity that many other agendas could be hidden under it. An early astronomy-related expedition turned out to be extremely beneficial, to botany. The expedition sent by the French Government in 1735 to South America under the leadership of Charles Marie de la Condamine (1701--1774) ostensibly for the measurement of an arc of the meridian at Quito in Ecuador surreptitiously collected data that enabled Linnaeus to describe the genus cinchona in 1742. When the pair of transits of Venus occurred in 1761 and 1769, France and England were engaged in a bitter rivalry for control of India. The observation of the transits became a part of the rivalry. A telescope presented by the British to a South Indian King as a decorative toy was borrowed back for actual use. Scientifically the transit observations were a wash out, but the exercise introduced Europe to details of living Indian tradition of eclipse calculations. More significantly, it led to the institutionalization of modern astronomy in India under the auspices of the English East India Company (1787). The transits of Venus of 1874 and 1882 were important not so much for the study of the events as for initiating systematic photography of the Sun. By this, Britain owned most of the world's sunshine, and was expected to help European solar physicists get data from its vast Empire on a regular basis. This and the then genuinely held belief that a study of the sun would help predict failure of monsoons led to the institutionalization of solar physics studies in India (1899). Of course, when the solar physicists learnt that solar activity did not quite determine rainfall in India, they forgot to inform the Government.
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
Ant colony optimization algorithms have long been touted as providing an effective and efficient means of generating high quality solutions to NP-hard optimization problems. Unfortunately, while the structure of the algorithm is easy to parallelize, the n...
This research merges the hierarchical reinforcement learning (HRL) domain and the ant colony optimization (ACO) domain. The merger produces a HRL ACO algorithm capable of generating solutions for both domains. This research also provides two specific impl...
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. PMID:17177315
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.
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
Although still often considered as simple unicellular organisms, in natural settings yeast cells tend to organize into intricate multicellular communities. Due to specific mechanisms only feasible at the population level, their capacity for social behavior is advantageous for their survival in a harmful environment. Feral Saccharomyces cerevisiae strains form complex structured colonies, which display many properties typical of natural biofilms causing (among others) serious infections in the human body. In our recent paper, we looked inside a growing colony using two-photon confocal microscopy. This allowed us to elucidate its three-dimensional colony architecture and some mechanisms responsible for community protection. Moreover, we showed how particular protective mechanisms complement each other during colony development and how each of them contributes to its defense against attacks from the environment. Our findings broaden current understanding of microbial multicellularity in general and also shed new light on the enormous resistance of yeast biofilms. PMID:22808334
Although still often considered as simple unicellular organisms, in natural settings yeast cells tend to organize into intricate multicellular communities. Due to specific mechanisms only feasible at the population level, their capacity for social behavior is advantageous for their survival in a harmful environment. Feral Saccharomyces cerevisiae strains form complex structured colonies, which display many properties typical of natural biofilms causing (among others) serious infections in the human body. In our recent paper, we looked inside a growing colony using two-photon confocal microscopy. This allowed us to elucidate its three-dimensional colony architecture and some mechanisms responsible for community protection. Moreover, we showed how particular protective mechanisms complement each other during colony development and how each of them contributes to its defense against attacks from the environment. Our findings broaden current understanding of microbial multicellularity in general and also shed new light on the enormous resistance of yeast biofilms.
In a study of seven massive, Caribbean corals, I have found major differences in reproductive behavior between species with large maximum colony sizes and species with smaller maximum colony sizes. Four species ( Diploria clivosa, D. strigosa, Montastrea cavernosa, Siderastrea siderea) which are large (<1000 cm2 in surface area) broadcast gametes during a short spawning season. Their puberty size is relatively large (>100 cm2, except M. cavernosa). In contrast, two small massive species (<100 cm2, Favia fragum and S. radians), and one medium-sized (100 1000 cm2, Porites astreoides) massive species, brood larvae during an extended season (year-round in Panama). The puberty size of the small species is only 2 4 cm2. Given these close associations between maximum colony sizes and a number of fundamental reproductive attributes, greater attention should be given to the colony size distributions of different species of reef corals in nature, since many important life history and population characters may be inferred.
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.
...colonies counted is used in the diagnosis of disease as a measure of the degree of bacterial infection. (b) Classification. Class I (general controls). The device is exempt from the premarket notification procedures in subpart E of...
...colonies counted is used in the diagnosis of disease as a measure of the degree of bacterial infection. (b) Classification. Class I (general controls). The device is exempt from the premarket notification procedures in subpart E of...
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
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
The Henry oblique transmitted-light viewing technique was modified to provide a more precise, convenient, and familiar manner with which to read (score) and recognize colonies of listeriae by their distinct bluish cast. The simplified technique involved illuminating each colony directly with a high-intensity lamp while viewing it with a hand lens at a precise angle in place of a scanning light microscope.
. ?Proteus mirabilis colonies display striking symmetry and periodicity. Based on experimental observations of cellular differentiation and group\\u000a motility, a kinetic model has been developed to describe the swarmer cell differentiation-dedifferentiation cycle and the\\u000a spatial evolution of swimmer and swarmer cells during Proteus mirabilis swarm colony development. A key element of the model is the age dependence of swarmer cell behaviour,
\\u000a This essay voices a de-colonial reading of peripheral Judaism. The de-colonial discourse reconfigures the racial, political,\\u000a and epistemological alliances that were put in place after the Holocaust. By departing from the limitations of one of the\\u000a most influential post-1945 European Jewish intellectuals, Emmanuel Levinas, I show the need to return to a narrative of Jewish\\u000a thought that neither reduces racial
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
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.
Marrow cells derived from C57BL\\/6 mice form many fewer splenic colonies in irradiated C57BL\\/6 × C3H F1 hybrid recipients than in irradiated C57BL\\/6 recipients (repression of colony formation). This effect is reversed by treatment of the hybrid recipients with active antiserum to mouse thymocytes. The repression phenomenon cannot readily be explained in immunological terms; hence the effect of the antilymphocyte
This paper examines the possible relationships between gender and nation in Irish culture, placing Ireland in the context of post?colonial theory and arguing that Gramsci's notion of the ‘subaltern’ (later adapted by post?colonial theorists) offers a useful way in which to begin to understand how gender and ‘Irishness’ co?exist. The paper argues that Gramsci's definition of the subaltern, when translated
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,
Fourier transform infrared and Raman microspectroscopy are currently being developed as new methods for the rapid identification of clinically relevant microorganisms. These methods involve measuring spectra from microcolonies which have been cultured for as little as 6 h, followed by the nonsubjective identification of microorganisms through the use of multivariate statistical analyses. To examine the biological heterogeneity of microorganism growth which is reflected in the spectra, measurements were acquired from various positions within (micro)colonies cultured for 6, 12, and 24 h. The studies reveal that there is little spectral variance in 6-h microcolonies. In contrast, the 12- and 24-h cultures exhibited a significant amount of heterogeneity. Hierarchical cluster analysis of the spectra from the various positions and depths reveals the presence of different layers in the colonies. Further analysis indicates that spectra acquired from the surface of the colonies exhibit higher levels of glycogen than do the deeper layers of the colony. Additionally, the spectra from the deeper layers present with higher RNA levels than the surface layers. Therefore, the 6-h colonies with their limited heterogeneity are more suitable for inclusion in a spectral database to be used for classification purposes. These results also demonstrate that vibrational spectroscopic techniques can be useful tools for studying the nature of colony development and biofilm formation. PMID:11282591
Choo-Smith, L P; Maquelin, K; van Vreeswijk, T; Bruining, H A; Puppels, G J; Ngo Thi, N A; Kirschner, C; Naumann, D; Ami, D; Villa, A M; Orsini, F; Doglia, S M; Lamfarraj, H; Sockalingum, G D; Manfait, M; Allouch, P; Endtz, H P
We apply the stochastic methods of statistical physics to analyse collective-decision making in social insect colonies, allowing us to derive the colony-level behaviour from an individual-level model. This contrasts with the traditional approach where a differential equation model, with or without arbitrary noise terms, is assumed. Social insect colonies vary in size from on the order 100 to 10,000,000 individuals, and such a statistical physics approach allows us explicitly to derive equations for both the average behaviour and the noise in the system, across this entire scale. We develop such a framework by building upon an existing stochastic model of opinion formation to model the decision-making processes in emigrating ant colonies. This new model is both driven by and evaluated against results from experiments with rock ants. This allows us to elucidate rigorously the role played by the individual-level phenomena of direct switching in the colony-level decision-making process, which optimality theory has predicted to be of crucial importance, and which we compare with our experimental results. This illustrates the power of the stochastic methods of statistical physics for understanding social insect colonies as complex systems.
Hogan, Patrick M.; Schlegel, Thomas; Franks, Nigel R.; Marshall, James A. R.
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
In vitro drug sensitivity testing, both by optical colony counting and by a [3H]-TdR incorporation assay, was performed on human tumour cells proliferating in soft agar cultures. Cells from two different human tumour cell lines, 5 different human tumour xenografts, and 94 different primary human tumour specimens of various histologic types were studied. Regression analysis comparing the results of the colony counting assay and the [3H]-TdR assay revealed good to excellent correlations between the two assay endpoints for quantitating the effect of in vitro anticancer drug exposure for a large number of different agents. The presence of pre-existing tumour cell aggregates complicates the performance of the optical colony counting assay. The [3H]-TdR incorporation assay is more sensitive and reproducible than the colony counting assay when performed on samples containing a large number of initially seeded tumour cell aggregates.
Jones, C. A.; Tsukamoto, T.; O'Brien, P. C.; Uhl, C. B.; Alley, M. C.; Lieber, M. M.
Through a comparative study of India and Pakistan's national security discourses, this article explores the linkages between post-colonial India and Pakistan's nationalist\\/communalist identities, configurations of masculinities, and gendered representations underpinning their nuclear (in)securities. This paper contends that the colonial politics of place-making in the sub-continent has not only inscribed a process of ‘othering’ between these states but has also facilitated
Summary We examined the conditions necessary for performing a reliable erythropoietin (EPO) assay based on CFU-E colony formation in fetal mouse liver cell (FMLC) microcultures using 96-well microtiter plates. Both linearity of colony numbers with the number of cells plated and comparison among the colony ratios at various densities of seeding cells indicated that the colonies originated from a single
Little is known in general about how group size or ectoparasitism affect survival in colonial animals. We estimated daily within-season survival probabilities for nesting adult and recently fledged juvenile cliff swallows ( Petrochelidon pyrrhonota) at 239 colonies from 1983 to 2003 in southwestern Nebraska, USA. Some colonies had been fumigated to remove ectoparasites. We conducted mark-recapture at each colony site
In this study I examined how the paper wasp, Polistes fuscatus, defends a colony when faced with a vertebrate attack. I looked for a division of labour in defensive behaviour within a colony and examined whether this behaviour changes over the colony cycle. The colonies were presented with a model of an adult red-winged blackbird, Agelaius phoeniceus, and a speaker
The polygyne form of the red imported Ţre ant, Solenopsis invicta Buren, is thought to occur primarily in discrete populations embedded within areas composed of monogyne colonies. This distribution implies that polygyne colonies compete with monogyne colonies and subsequently create a population homogenous in social form. Because polygyne colonies produce mostly sterile males, opportunities for insemination of female alates might
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
Three studies were conducted to assess the effects of the entomopathogen Thelohania solenopsae on polygynous, red imported Ţre ant, Solenopsis invicta Buren, colonies. A total of 57 of 122 queens (46.7%) from nine, Ţeld-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
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
We estimated survival and movement probabilities in relation to breeding-colony size in the sociable weaver (Philetairus socius) by using multistate statistical methods, in which survival and movement to time t + 1 is conditional on an individual's colony size at time t. The sociable weaver is a colonial, cooperatively breeding species that builds a massive communal nest, with colony size
Charles R. Brown; Rita Covas; Mark D. Anderson; Mary Bomberger Browna
Ant colonies emigrate frequently from one nest site to another. Emigrations, however, are dangerous, particularly for colonies with a single queen. The queen is a ''vital organ'' of the colony, and emigrations expose her to grave peril. The optimal strategy for a monogynous ant colony, therefore, should be that the queen moves during the middle of the emigration so that
Individually labeled freshly emerged honeybee workers (Apis mellifera) from three unre- lated source colonies were introduced into five host colonies. The location of the workers during their first eight days of life was monitored. Workers from the same source colony tended to be found more often in the same area of the comb than workers from a different source colony.
Robin F. A. Moritz; Robin M. Crewe; H. Randall Hepburn
Colony number in many colony calculating experiments is counted by manual method at present, therefore it is difficult to get the result quickly and accurately when the number of experimental sample is large. A new automatic colony counting system was developed, which makes use of image-processing technology to feasibly count white bacterial colonies in clear plates according to the RGB
Sylvatic plague (Yersinia pestis) is an exotic pathogen that is highly virulent in black-tailed prairie dogs (Cynomys ludovicianus) and causes widespread colony losses and individual mortality rates >95%. We investigated colony spatial characteristics that may influence inter-colony transmission of plague at 3 prairie dog colony complexes in the Great Plains. The 4 spatial characteristics we considered include: colony size, Euclidean distance to nearest neighboring colony, colony proximity index, and distance to nearest drainage (dispersal) corridor. We used multi-state mark-recapture models to determine the relationship between these colony characteristics and probability of plague transmission among prairie dog colonies. Annual mapping of colonies and mark-recapture analyses of disease dynamics in natural colonies led to 4 main results: 1) plague outbreaks exhibited high spatial and temporal variation, 2) the site of initiation of epizootic plague may have substantially influenced the subsequent inter-colony spread of plague, 3) the long-term effect of plague on individual colonies differed among sites because of how individuals and colonies were distributed, and 4) colony spatial characteristics were related to the probability of infection at all sites although the relative importance and direction of relationships varied among sites. Our findings suggest that conventional prairie dog conservation management strategies, including promoting large, highly connected colonies, may need to be altered in the presence of plague. ?? 2011 The Wildlife Society.
Johnson, T. L.; Cully, Jr. , J. F.; Collinge, S. K.; Ray, C.; Frey, C. M.; Sandercock, B. K.
Summary This study investigated the effects of colony growth and development, food storage, foraging activity and weather on the migration behavior of African honey bees in the Okavango River Delta, Botswana. Four observation colonies were studied during the honey bee migration season (November–May), at which time the availability of blooming species was reduced. Two of the colonies (colonies 1 &
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
It is known that some kinds of intelligent behavior can be realized by utilizing a model of an ant colony in which ants act by exchanging information with one another via virtual pheromone. This model is called ant colony model or ant colony optimization. The ant colony model often makes the ants generate routes that look like patterns similar to
Abstract The phenotypes ,of thirty queenright honeybee ,colonies with naturally mated ,queens ,were evaluated over a two years period. Colony size, honey yields and colony levels of infestation with Varroa jacobsoni were ,assessed. Worker samples were taken from each tested colony. Individual workers were genotyped at four DNA-microsatellite loci to determine the degree of polyandry. We found significant correlations between
Peripheral blood mononuclear cells from patients with polycythemia vera or myelofibrosis with myeloid metaplasia were studied for their erythroid colony growth characteristics in plasma clot cultures. In both diseases, erythroid colonies formed early in culture in the absence of added erythropoietin (endogenous colonies). In no instance did early, endogenous colony formation occur with peripheral blood cells from normals or patients
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.
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.
"This paper is part of a larger project investigating the production and regulation of North African immigrants in the greater Paris automobile industry. Its aims are twofold. First, to reverse the emphasis placed on immigrants in the receiving countries and to (re-)explore the historical production of Algerian emigration into metropolitan industry, more specifically within the automobile industry....Second, in adopting an żarticulation of modes of production' (AMOP) narrative as an alternative to other Eurocentric approaches, the first part of this paper emphasizes the contradictory layering of various modes which have produced an Algerian colonial diaspora. The latter half of the paper argues that the history of post-independence Algeria confirms that emigration was reinforced through a complex neocolonial relationship during a period of rapid acceleration of Algerian migration to France." PMID:12292879
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.
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. PMID:21246044
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
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
In botryllid ascidians, allogeneic contacts between histoincompatible colonies lead to inflammatory rejection responses, which eventually separate the interacting colonies. In order to elucidate the molecular background of allogeneic rejection in the colonial ascidian Botryllus schlosseri, we performed microarray assays verified by qPCR, and employed bioinformatic analyses of the results, revealing disparate transcription profiles of the rejecting partners. While only minor expression changes were documented during rejection when both interacting genotypes were pooled together, analyses performed on each genotype separately portrayed disparate transcriptome responses. Allogeneic interacting genotypes that developed the morphological markers of rejection (points of rejection; PORs), termed 'rejected' genotypes, showed transcription inhibition of key functional gene groups, including protein biosynthesis, cell structure and motility and stress response genes. In contrast, the allogeneic partners that did not show PORs, termed 'rejecting' genotypes, showed minor expression changes that were different from those of the 'rejected' genotypes. This data demonstrates that the observed morphological changes in the 'rejected' genotypes are not due to active transcriptional response to the immune challenge but reflect transcription inhibition of response elements. Based on the morphological and molecular outcomes we suggest that the 'rejected' colony activates an injurious self-destructive mechanism in order to disconnect itself from its histoincompatible neighboring colony. PMID:20452026
We investigate the relationship of incubation time and forward-scattering signature for bacterial colonies grown on solid nutrient surfaces. The aim of this research is to understand the colony growth characteristics and the corresponding evolution of the scattering patterns for a variety of pathogenic bacteria relevant to food safety. In particular, we characterized time-varying macroscopic and microscopic morphological properties of the growing colonies and modeled their optical properties in terms of two-dimensional (2-D) amplitude and phase modulation distributions. These distributions, in turn, serve as input to scalar diffraction theory, which is, in turn, used to predict forward-scattering signatures. For the present work, three different species of Listeria were considered: Listeria innocua, Listeria ivanovii, and Listeria monocytogenes. The baseline experiments involved the growth of cultures on brain heart infusion (BHI) agar and the capture of scatter images every 6 h over a total incubation period of 42 h. The micro- and macroscopic morphologies of the colonies were studied by phase contrast microscopy. Growth curves, represented by colony diameter as a function of time, were compared with the measured time-evolution of the scattering signatures. PMID:18315368
Bae, Euiwon; Banada, Padmapriya P; Huff, Karleigh; Bhunia, Arun K; Robinson, J Paul; Hirleman, E Daniel
Intraspecific phenotypic diversification in social organisms often leads to formation of physical castes which are morphologically specialized for particular tasks within the colony. The optimal caste allocation theory argues that specialized morphological castes are efficient at specific tasks, and hence different caste ratios should affect the ergonomic efficiency, hence reproductive output of the colony. However, the reproductive output of different caste ratios has been documented in few species of insects with equivocal support for the theory. This study investigated whether the ratios of nonreproductive and reproductive morphs affect the reproductive output of a recently discovered social trematode, Philophthalmus sp., in which the nonreproductive members are hypothesized to be defensive specialists. A census of natural infections and a manipulative in vitro experiment demonstrated a positive association between the reproductive output of trematode colonies and the ratio of nonreproductive to reproductive morphs in the presence of an intra-host trematode competitor, Maritrema novaezealandensis. On the contrary, without the competitor, reproductive output was negatively associated with the proportion of nonreproductive castes in colonies. Our findings demonstrate for the first time a clear fitness benefit associated with the nonreproductive castes in the presence of a competitor while illustrating the cost of maintaining such morphs in noncompetitive situations. Although the proximate mechanisms controlling caste ratio remain unclear in this trematode system, this study supports the prediction that the fitness of colonies is influenced by the composition of specialized functional morphs in social organisms, suggesting a potential for adaptive shifts of caste ratios over evolutionary time. PMID:23252707
The Colonie site is a DOE Formerly Utilized Sites Remedial Action Program (FUSRAP) site located in the Town of Colonie, New York, and consisting of an interim storage site and several vicinity properties. The Colonie Interim Storage Site (CISS) is the former National Lead (NL) Industries plant located at 1130 Central Avenue. There are 11 vicinity properties that received remedial action in 1984: 7 located south of the site on Yardboro and Palmer Avenues just across the Colonie-Albany town limits in Albany, and 4 located northwest of the site along Central Avenue in Colonie. Of these properties, nine are residences and two are commercial properties. This document describes the engineering design, construction, and associated plans for remedial action on the vicinity properties and the interim storage site. These plans include both radiological and chemical work. Radiological work includes: excavating the above-guideline radioactive wastes on the vicinity properties; designing required facilities for the interim storage site; preparing the interim storage site to receive these contaminated materials; transporting the contaminated materials to the interim waste storage stockpile; and preparing necessary schedules for accomplishing the remedial actions. Chemical work involves: developing the Resource Conservation and Recovery Act (RCRA) closure plans; neutralizing chemical hazards associated with plating solutions; inventorying on-site chemicals; and disposal of chemicals and/or residues. 17 refs., 5 figs., 1 tab.
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.
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.
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.
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.
Many dynamical networks, such as the ones that produce the collective behavior of social insects, operate without any central control, instead arising from local interactions among individuals. A well-studied example is the formation of recruitment trails in ant colonies, but many ant species do not use pheromone trails. We present a model of the regulation of foraging by harvester ant (Pogonomyrmex barbatus) colonies. This species forages for scattered seeds that one ant can retrieve on its own, so there is no need for spatial information such as pheromone trails that lead ants to specific locations. Previous work shows that colony foraging activity, the rate at which ants go out to search individually for seeds, is regulated in response to current food availability throughout the colony's foraging area. Ants use the rate of brief antennal contacts inside the nest between foragers returning with food and outgoing foragers available to leave the nest on the next foraging trip. Here we present a feedback-based algorithm that captures the main features of data from field experiments in which the rate of returning foragers was manipulated. The algorithm draws on our finding that the distribution of intervals between successive ants returning to the nest is a Poisson process. We fitted the parameter that estimates the effect of each returning forager on the rate at which outgoing foragers leave the nest. We found that correlations between observed rates of returning foragers and simulated rates of outgoing foragers, using our model, were similar to those in the data. Our simple stochastic model shows how the regulation of ant colony foraging can operate without spatial information, describing a process at the level of individual ants that predicts the overall foraging activity of the colony. PMID:22927811
Prabhakar, Balaji; Dektar, Katherine N; Gordon, Deborah M
Science education in Papua New Guinea has been influenced by neo-colonial practices that have significantly contributed to the silencing of the Papua New Guinea voice. This silencing has led to the production of science curriculum documents that are irrelevant to the students for whom they are written. To avoid being caught up in neo-colonial practices, Western science educators ought to consider the notion of cultural mediators. This position, I argue, infers an obligation to take responsibility for their actions and to consider postcolonial discourses as a way of understanding the relationships and dialogue between different ways of knowing.
We study the growth of colonies of the yeast Pichia membranaefaciens on agarose film. The growth conditions are controlled in a setup where nutrients are supplied through an agarose film suspended over a solution of nutrients. As the thickness of the agarose film is varied, the morphology of the front of the colony changes. The growth of the front is modeled by coupling it to a diffusive field of inhibitory metabolites. Qualitative agreement with experiments suggests that such a coupling is responsible for the observed instability of the front.
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
Statistical properties and patterns of bacterial colony formed by the twitching motility are studied from the viewpoint of both computer simulations and experimental examinations. Models of four kinds of bacterial motion are proposed and the growing bacterial colonies due to the models are simulated by means of Monte Carlo method. Macroscopic patterns of the bacterial colonies and orientational order parameters of the bacteria are analyzed. By comparing the simulation results with the colony pattern formed by Thermus thermophilus, we suggest that wriggling edge of the colony is caused by slingshot-like motions of bacteria.
In this study I examined how the paper wasp, Polistes fuscatus, defends a colony when faced with a vertebrate attack. I looked for a division of labour in defensive behaviour within a colony and examined whether this behaviour changes over the colony cycle. The colonies were presented with a model of an adult red-winged blackbird, Agelaius phoeniceus, and a speaker that vibrated the comb. There was a pronounced division of labour in the defence against vertebrate predators within a colony. The queen was consistently the most aggressive individual in the colony. The subordinate foundresses and workers both became more aggressive towards a vertebrate predator as they aged. Gynes and males did not participate in colony defence. The level of aggression in colony members of P. fuscatus appears to be related to the reproductive investment of the colony. Copyright 2000 The Association for the Study of Animal Behaviour. PMID:10924203
|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…
|A history of primary school curriculum in Guyana, a former British colony, points out social determinates of curriculum. Ruling groups emphasized agriculture and manual arts in public education to maintain class distinctions while the masses fought for academic education as a key to financial and social success. (JH)|
Using cross-country data for about 70 countries and regional data for about 180 African provinces, we show that competition between Protestant and Catholic missionaries increased schooling in former colonies. Our evidence implies that Protestant missionaries increased schooling in Catholic countries by more than Catholic missionaries, but we cannot reject the hypothesis that the e ect of Protestant and Catholic missionaries
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
Ant Colony Optimization (ACO) is a meta- heuristic introduced by Dorigo et al. (9) which uses ideas from nature to find solutions to instances of the Travelling Salesman Problem (TSP) and other combinatorial optimisation problems. In this paper we analyse the parameter settings of the ACO algo- rithm. These determine the behaviour of each ant and are critical for fast
Within the Linguistic Modeling Ţeld, one of the most important applications of Fuzzy Rule-Based Systems, the automatic learning from numerical data of the fuzzy linguistic rules composing these systems is an important task. In this paper we introduce a novel way of addressing the problem making use of Ant Colony Optimization (ACO) algorithms. To do so, the learning task will
In this paper, we investigate the performance of the fuzzy entropy approach when it is applied to the segmentation of infrared objects. Through a number of examples, the performance is compared with those using existing entropy-based object segmentation approaches and the superiority of the fuzzy entropy method is demonstrated. In addition, the ant colony optimization (ACO) is used to obtain
The Vehicle Routing Problem (VRP) requires the determination of an optimal set of routes for a set of vehicles to serve a set of customers. We deal here with the Capacitated Vehicle Routing Problem (CVRP) where there is a maximum weight or volume that each vehicle can load. We developed an Ant Colony algorithm (ACO) for the CVRP based on
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
The field of ACO algorithms is very lively, as testified, for example, by the successful biannual workshop (ANTS—From Ant Colonies to Artificial Ants: A Series of International Workshops on Ant Algorithms; http:\\/\\/iridia.ulb.ac.be\\/~ants\\/) where researchers meet to discuss the properties of ACO and other ant algorithms, both theoretically and experimentally.
An ant colony algorithm-based approach to assembly sequence generation and optimization of mechanical products is presented in this article. For diverse assemblies, the approach generates different amount of ants cooperating to find optimal solutions with the least reorientations during assembly processes. Based on assembly by disassembly philosophy, a candidate list composed by feasible and reasonable disassembly operations that are derived
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
Ant Colony Optimization (ACO) has become quite popular in recent years. In contrast to many successful applications, the theoretical founda- tion of this randomized search heuristic is rather weak. Building up such a theory is demanded to understand how these heuristics work as well as to come up with better algorithms for certain problems. Up to now, only convergence results
We deal with the application of ant colony optimization to group shop scheduling, which is a general shop scheduling problem that includes, among others, the open shop scheduling problem and the job shop scheduling problem as special cases. The contributions of this paper are twofold. First, we propose a neighborhood structure for this problem by extending the well-known neighborhood structure
Ant Colony Optimisation (ACO) is a constructive metaheuristic that uses an analogue of ant trail pheromones to learn about good features of solutions. Critically, the phero- mone representation for a particular problem is usually chosen intuitively rather than by following any systematic process. In some representations, distinct solutions appear mul- tiple times, increasing the eective size of the search space
The conventional approaches to routing and bandwidth allocation, the two major components of traffic engineering, have proved insufficient to address QoS requirements of flows while optimizing utilization for complex communication networks. In this paper we consider ant colony algorithms to address this problem. Our studies show that the ant-based routing models are sensitive to initial parameters settings. Only careful adjustments
Ali Tizghadam; Massoud Hashemi; Alberto Leon-Garcia
A new UAV path planning method based on ant colony optimization (ACO) is presented. The target position is considered as the food source which the ants are going to find. The enemy defense region is considered as the searching area of the ants and is divided into equally spaced grids. The ants move to the destination node through several nodes
Information is presented which updates current seabird breeding colony locations in the Lesser An- tilles. No evidence of breeding was found for Black-capped Petrels (Pterodroma hasitata) in Dominica. Audu- bon's Shearwater (Puffinus lherminieri) was found nesting on the St. Martin islet of Tintamarre. Incubating Red- billed Tropicbirds (Phaethon aethereus) were recorded in Anguilla and St. Martin. White-tailed Tropicbird (Phaethon lepturus)
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.
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)
|The social, economic, and political regulation of Canada's First Nations was codified in the Indian Act. Rooted in colonialism and paternalism, the Indian Act was created by the government of Canada to fulfill three functions: (1) to define who was and was not an Indian; (2) to civilize the Indian; and (3) to manage the Indian people and their…
White stork,Ciconia ciconia, chicks were observed to abandon their natal nests prior to independence and to be adopted by neighbouring foster parents in approximately 40% of broods at three breeding colonies. Nest switching coincided with a decrease in feeding rates by parents and an increase in aggression by siblings triggered by the flight exercises of nestmates, and mainly affected the
TOMAS REDONDO; FRANCISCO S. TORTOSA; LUIS ARIAS deREYNA
A study of Canadian Indigenous fathers' involvement conceptualized a temporal horizon within which to situate challenges and opportunities for caring for children following decades of colonial interventions that have diminished men's roles. Through five community-university partnerships, conversational interviews were held with eighty First Nations and Métis fathers in British Columbia, Canada. Using a grounded theory approach, a conceptual model was
From the first English settlement in colonial America to the beginning of the Revolution, the legal status of account books evolved. During this period, there was a scarcity of hard currency which made commercial transactions largely dependent upon a credit based, barter based economic system. Business transactions often were represented by book debt. As merchants brought legal actions over book
6. AERIAL OBLIQUE FROM EAST, SHOWING QUONSET POINT SUMMER COLONY IN FOREGROUND, NEUTRALITY PATROL HANGAR (BLDG. 2) ON LEFT, RHODE ISLAND NATIONAL GUARD FACILITIES IN CENTER. NATIONAL GUARD DISPENSARY SURVIVES AS BLDG. 435. USN PHOTO, C. MARCH, 1940. - Quonset Point Naval Air Station, Roger Williams Way, North Kingstown, Washington County, RI
Contextualization In the nineteenth century Mäori masculine physicality was, like the untamed countryside, something to be conquered and civilized; in the twentieth century it was something to be harnessed to provide manual labor for New Zealand’s developing colonial nation; in the twenty-first century it has become a spectacle played out by the overachievement of täne (Mäori men) on the sports
In the present study, yeast colony development serves as a model system to study growth of fungal populations with negligible nutrient and signal transport within the mycelium. Mathematical simulations address the question whether colony development is governed by diffusional limitation of nutrients. A hybrid one-dimensional cellular automaton model was developed that describes growth of discrete cells based upon microscopic interaction rules in a continuous field of nutrient and messenger. The model is scaled for the geometry of the experimental setup, cell size, growth- and substrate uptake rates. Therefore, calculated cell density profiles and nutrient distributions can be compared to experimental results and the model assumptions can be verified. In the physiologically relevant parameter range, simulations show an exponentially declining cell density along the median axis of the colonies in case of a diffusion limited growth scenario. These results are in good agreement with cell density profiles obtained in cultivations of the yeast Candida boidinii with glucose as the limiting carbon source but stand in contrast to the constant cell density profile estimated for Yarrowia lipolytica grown under the same conditions. While from the comparison of experimental results and simulations a diffusion limited growth mechanism is proposed for glucose limited C. boidinii colonies, this hypothesis is rejected for the growth of Y. lipolytica. As an alternative, a quorum sensing model was developed that can explain the evolution of constant cell density profiles based on the effect of a not further characterized unstable or volatile messenger. PMID:15234200
With the emergence of many environmentalisms, the terms of discourse in the green public sphere are changing, particularly now to take account of international, transnational and global contexts. As it expands in scope, the green public sphere encounters a planet divided not only in regard to rich and poor countries, but also in relation to the legacy of colonialism. Examining
Astronomy played a unique role in Australia in the movement from a non- scientific society (Phase 1 of Basalla's model) through colonial science (Phase 2) to independent science (Phase 3) and was thus an important element, arguably the most important, in the country's liberation from the scientific imperialism of Britain. In parallel with their attempts to colonise and reconstruct the
The distribution of Calyptogena phaseoliformis colonies in right-stepping en echelon patterns was observed by the Japanese submersible Shinkai 6500 at the foot of the landward escarpment of the northern Japan Trench at around 6437 6274 m depth. The north-south trending Sanriku Escarpment has a thrust origin and is subparallel to the trench axis along which the Pacific plate is being subducted beneath the North America or Okhotsk plate at about 300° at a rate of about 7.8 to 8.3 cm/yr. The trends of colonies are concentrated at 250°, 300°, and 330°: each trend matches either an antithetic riedel shear, extension fracture, or synthetic riedel shear, respectively, within a left-lateral shear regime caused by the oblique subduction. Methane- and hydrogen sulfide bearing fluid advection from depth occurs essentially along the thrust fault, but finally seeps along the fractures at the sea floor. This supplies energy to the food chain through bacteria utilizing hydrogen sulfide, then eventually sustains the Calyptogena colonies. Because the clams select the best places to survive, the geometric arrangement of the clam colonies provides a kinematic indicator of relative plate motions.
Ogawa, Yujiro; Fujioka, Kantaro; Fujikura, Katsunori; Iwabuchi, Yo
Summary The genetic profile of the Varroa destructor mite infesting Apis mellifera iberiensis colonies located in the Iberian Peninsula and also on Canarian and Balearic islands was determined through standard molecular assays (RFLP of the mitochondrial cox1 fragment). The V. destructor Korea haplotype was found in all of the 575 samples analyzed except in one, confirming the worldwide expansion of
Irene Muńoz; Encarna Garrido-Bailón; Raquel Martín-Hernández; Aranzazu Meana; Mariano Higes; Pilar De la Rúa
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
Hematopoietic stem cells (HSCs) present in small numbers in adult bone marrow (BM), peripheral blood (PB) and umbilical cord blood (CB) produce a heterogeneous pool of progenitors that can be detected in vitro using colony forming cell (CFC) assays. Hematopoietic progenitor cells proliferate and differentiate to produce colonies of maturing cells when cultured in a semisolid methylcellulose-based medium that is supplemented with suitable growth factors and other supplements. The colonies are then classified and enumerated in situ by light microscopy or an automated imaging instrument. CFC assays are important tools in basic hematology research but are also used by clinical cell processing laboratories to measure the progenitor cell content of BM, CB and mobilized PB (MPB) preparations used for cell transplantation. Standard CFC assays for human progenitor cells require a culture period of at least 14 days to enable optimal outgrowth and differentiation of the maximum number of CFCs in a cell preparation. In this chapter protocols are described for the detection and enumeration of myeloid multipotential progenitors and committed progenitors of the erythroid, monocyte, and granulocyte lineages in samples from human PB, MPB, BM, and CB. In addition protocols are described for a modified version of the CFC-assay that allows accurate enumeration of total CFC numbers in CB or MPB after a culture period of only 7 days, but without distinction of colony types. PMID:23179838
Wognum, Bert; Yuan, Ning; Lai, Becky; Miller, Cindy L
In this article, I attempt to articulate a new understanding of the colonial encounter between the Sikhs and the British by arguing that the modern political sovereignty of the West is founded not only on the control and disciplining of bodies, but also on a theft of bodies. I read the extraordinary agonies and torments suffered by Maharani Jindan and
|The author fantasizes that at some point in the distant past England was a Spanish colony. He supports his thesis by revealing fantastic etymologies of some English place names showing the influence of Spanish on English, for example "Surrey" comes from "su rey." (Text is in Spanish.) (TL)|
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
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
Cordylophora caspia, a colonial hydrozoan native to the Ponto-Caspian region, has become a common invader of both fresh and brackish water ecosystems of North America and Europe. Here we describe 11 polymorphic microsatellite loci for this species. Preliminary analyses indicate ...
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.
Introduces this volume of the journal, which focuses on language in education in post-colonial Hong Kong. Before Hong Kong was returned to China, Cantonese and English were the predominate languages; since the change of sovereignty, the status of Mandarin has increased tremendously. (Author/VWL)
This paper draws on the work of Homi Bhabha to mount an explanation for a facet of (post)colonial racism, the 'paradox of otherness' as exemplified in the racial stereotype. The paradox in question operates at the levels of discourse and identification alike. As a mode of discourse the stereotype functions to exaggerate difference of the other, whilst nevertheless attempting to
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 (ĽSDAY). 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
An Ants System is an artificial system based on the behavior of real ant colonies, which is used to solve combinatorial problems. This is a distributed algorithm composed by a set of cooperating agents called ants which cooperate among them to find good solutions to combinatorial optimization problems. The cooperation follows the behavior of real ants using an indirect form
Ant Colony Optimization (ACO) is a metaheuristic that is inspired by the shortest path searching behavior of various ant species [1,2]. The initial work of Dorigo, Maniezzo and Colorni [3,4] who proposed the first ACO algorithm called Ant System, has stimulated a still strongly increasing number of researchers to develop more sophisticated and better performing ACO algorithms that are used
Oscar Cordón García; Francisco Herrera Triguero; Thomas Stützle
This article examines how a gendered discourse of taste was formulated in colonial Bengal by the Bengali Hindu middle classes, which in its turn facilitated the self-fashioning of Bengali bhadralok. This discourse of taste was articulated specifically through the culture of food. The middle-class Bengali Hindus constituted a new rhetoric of cuisine that enabled them to distance themselves from their
Data mining is a process that uses technology to bridge the gap between data and logical decision-making. The jargon itself offers a promising view of organized data manipulation for extracting valuable information and knowledge from high volume of data. Copious techniques are developed to fulfill this aspiration. This paper outlines an ant colony optimization algorithm which is used newly in
|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…
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
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
This article examines settler attitudes toward the law and the legal system in early colonial Kenya. Settlers believed that English law was the culmination of centuries of evolution and was unsurpassed for its justice and logic. Nonetheless, they insisted English law and legal procedure were supremely ill-suited for the African context. When courts released Africans on “technicalities” it only encouraged
|Transcribing and footnoting some 186 family letters and documents which revolve around social life at Antioch College (Ohio) in the 1870s and everyday life during the same period allowed a professor to examine a metaphor for personal relationships used at the time: colonialism. His great grandmother, a young widow with three minor children, moved…
This paper narrates the life of Ezekiel Cheever, the most famous colonial New England Latin grammar teacher of his time. Cheever came from middle class Puritan roots in England, receiving a classical education before emigrating to Boston (Massachusetts). His remarkably long teaching career of 70 years in four New England towns and the esteem shown…
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.
In 11 Apis mellifera colonies with laying queens, about 0.12% of the males produced derived from eggs laid by workers. This result requires explanation both of why workers produce any males, and, since they do, why they produce so few. Workers may maximize their inclusive fitness by forgoing reproduction, or their sterility may be due to to enforcement of the
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)
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)
The 'benefits of philopatry' hypothesis states that helpers in cooperatively breeding species derive higher benefits from remaining home, instead of dispersing and attempting to breed independently. We tested experimentally whether dispersal options influence dispersal propensity in the cooperatively breeding Lake Tanganyika cichlids Neolamprologus pulcher and N. savoryi. Cooperative groups of these fishes breed in densely packed colonies, surrounded by unoccupied,
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,...
Many cultural and ethnic minorities have extensive experiences of being oppressed, which they may eventually internalize. However, psychology has yet to actively incorporate various forms of internalized oppression (e.g., colonial mentality [CM]) into the etiological conceptualizations of psychopathology. Using a sample of 248 Filipino Americans, the author tested a more complete and sociopolitically informed cultural model of depression symptoms. Results
In the 1930s, as literature and films representing the British empire were disseminated in Britain, the United States and colonial India, the narratives were transformed through reception and adaptation. The genre of pro-imperial or ‘empire films’ produced by British studios celebrated the continued international relevance of the British empire at a time of contestation by nationalist movements. American film adaptations
Users can have access to resources and obtain services at anytime and anywhere in ubiquitous computing environment. By virtue of behavior experience in human society, according to dynamic evolution discipline of the contradiction between the lag of trust and the anteriority of service, and the self-organization, distributed computing and regenerative feedback characteristics of ant colony algorithm, cascade service selection model
Based on Markowitz' theory of asset portfolio, a multiple-goal optimization model of portfolio investment was set up considering both risk and return. Then applying ant colony optimization algorithm to solve the model, we got a better result than that of using Lingo.
3-D object segmentation is an important and challenging topic in computer vision that could be tackled with artificial life models. A Channeler Ant Model (CAM), based on the natural ant capabilities of dealing with 3-D environments through self-organization and emergent behaviours, is proposed. Ant colonies, defined in terms of moving, pheromone laying, reproduction, death and deviating behaviours rules, is able
Piergiorgio Cerello; Sorin Christian Cheran; Francesco Bagagli; Stefano Bagnasco; Roberto Bellotti; Lourdes Bolanos; Ezio Catanzariti; Giorgio De Nunzio; Elisa Fiorina; Gianfranco Gargano; Gianluca Gemme; Ernesto Lopez Torres; Gian Luca Masala; Cristiana Peroni; Matteo Santoro
During their development and aging on solid substrates, yeast giant colonies produce ammonia, which acts as a quorum sensing molecule. Ammonia production is connected with alkalization of the surrounding medium and with extensive reprogramming of cell metabolism. In addition, ammonia signaling is important for both horizontal (colony centre versus colony margin) and vertical (upper versus lower cell layers) colony differentiations. The centre of an aging differentiated giant colony is thus composed of two major cell subpopulations, the subpopulation of long-living, metabolically active and stress-resistant cells that form the upper layers of the colony and the subpopulation of stress-sensitive starving cells in the colony interior. Here, we show that microcolonies originating from one cell pass through similar developmental phases as giant colonies. Microcolony differentiation is linked to ammonia signaling, and cells similar to the upper and lower cells of aged giant colonies are formed even in relatively young microcolonies. A comparison of the properties of these cells revealed a number of features that are similar in microcolonies and giant colonies as well as a few that are only typical of chronologically aged giant colonies. These findings show that colony age per se is not crucial for colony differentiation.
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
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.
During June and July of 2009, sudden deaths, tremulous movements and population declines of adult honey bees were reported by the beekeepers in the region of Peloponnesus (Mt. Mainalo), Greece. A preliminary study was carried out to investigate these unexplained phenomena in this region. In total, 37 bee samples, two brood frames containing honey bee brood of various ages, eight sugar samples and four sugar patties were collected from the affected colonies. The samples were tested for a range of pests, pathogens and pesticides. Symptomatic adult honey bees tested positive for Varroa destructor, Nosema ceranae, Chronic bee paralysis virus (CBPV), Acute paralysis virus (ABPV), Deformed wing virus (DWV), Sacbrood virus (SBV) and Black queen cell virus (BQCV), but negative for Acarapis woodi. American Foulbrood was absent from the brood samples. Chemical analysis revealed that amitraz, thiametoxan, clothianidin and acetamiprid were all absent from symptomatic adult bees, sugar and sugar patty samples. However, some bee samples, were contaminated with imidacloprid in concentrations between 14 ng/g and 39 ng/g tissue. We present: the infection of Greek honey bees by multiple viruses; the presence of N. ceranae in Greek honey bees and the first record of imidacloprid (neonicotonoid) residues in Greek honey bee tissues. The presence of multiple pathogens and pesticides made it difficult to associate a single specific cause to the depopulation phenomena observed in Greece, although we believe that viruses and N. ceranae synergistically played the most important role. A follow-up in-depth survey across all Greek regions is required to provide context to these preliminary findings. PMID:20804765
Bacandritsos, N; Granato, A; Budge, G; Papanastasiou, I; Roinioti, E; Caldon, M; Falcaro, C; Gallina, A; Mutinelli, F
Bird use of dredged material islands in five areas of Florida was studied. The use of these islands by birds, particularly by colonial nesting sea and wading birds, was documented with two visits to each of 40 selected islands in five study areas in 1977....
To compare the social structure of primitively social wasps with that of communal breeding vertebrates, we used a new technique based on micro videocameras applied to the nest envelope to study the organization of behavior in Malaysian colonies of the stenogastrine wasp Eustenogaster fraterna. The reproductive division of labor in this species appears to be different from that reported so
Temporal and spatial analyses are seldom utilized in the study of colony genetic structure, but they are potentially powerful methods which can yield novel insights into the mechan- isms underlying variation in breeding systems. Here we present the results of a study which incorporated both of these dimensions in an examination of genetic structure of sub- terranean termites in the
Residual radioactive material guidelines for uranium in soil were derived for the Colonie site located in Colonie, New York. This site has been designated for remedial action under the Formerly Utilized Sites Remedial Action Program (FUSRAP) of the U.S. Department of Energy (DOE). The site became contaminated with radioactive material as a result of operations conducted by National Lead (NL) Industries from 1958 to 1984; these activities included brass foundry operations, electroplating of metal products, machining of various components using depleted uranium, and limited work with small amounts of enriched uranium and thorium. The Colonie site comprises the former NL Industries property, now designated the Colonie Interim Storage Site (CISS), and 56 vicinity properties contaminated by fallout from airborne emissions; 53 of the vicinity properties were previously remediated between 1984 and 1988. In 1984, DOE accepted ownership of the CISS property from NL Industries. Residual radioactive material guidelines for individual radionuclides and total uranium were derived on the basis of the requirement that the 50-year committed effective dose equivalent to a hypothetical individual who lives or works in the immediate vicinity of the site should not exceed a dose of 30 mrem/yr following remedial action for the current use and likely future use scenarios or a dose of 100 mrem/yr for less likely future use scenarios. The DOE residual radioactive material guideline computer code, RESRAD, was used in this evaluation; RESRAD implements the methodology described in the DOE manual for establishing residual radioactive material guidelines.
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.
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.
The authors located and surveyed 7 active seabird colonies in northeast Prince William Sound (Port Gravina to Nelson Bay), including 3 colonies not previously reported. Additionally at 2 historic colonies, Redhead and Hanks Island, the authors were not ab...
Colonial web-building spiders respond to trade-offs between selective forces relative to spatial position within colonies and thus provide support for the selfish herd theory. The size distribution of spiders within colonies of Metepeira incrassata, a colonial orb-weaver (Araneae: Araneidae) from tropical Mexico is nonrandom; larger (mature) spiders and females guarding eggsacs are more prevalent in the center, whereas more small
Morphological characteristics of an edible terrestrial cyanobacteriumNostoc flagelliforme in liquid suspension cultures under photoautotrophic conditions are presented. Different cell forms alternated in a regular\\u000a manner during the experimentation period (30 d).N. flagelliforme exhibited a very complex life cycle in terms of colony morphology, including mainly 4 different colony morphological forms,viz. hormogonia, filaments, seriate colonies and aseriate colonies. Under laboratory conditions
The small hive beetle (SHB) is a parasite and scavenger of honeybee colonies. Here we provide the first comprehensive systematic\\u000a data on colony infestation levels with adult SHB for 226 colonies at 31 apiaries in South Africa, Australia, Florida and Maryland.\\u000a Inside colonies, SHB distribution was influenced by the presence of bees with more SHB in the brood nest in
Sebastian Spiewok; Jeff S. Pettis; Michael Duncan; Robert Spooner-Hart; David Westervelt; Peter Neumann
The growth of macroscopic hemopoietic colonies was observed during postradiation regeneration in the spleen of dwarf hamsters (as well as of mice). The erythroid, granulocyte and megakaryocyte colonies were morphologically identified. The ratio between the erythroid and granulocyte colonies amounts to approximately 11. The formation of macroscopic spleen colonies and their morphology can be used for the functional characterization of hemopoietic microenvironment in the dwarf hamster. PMID:6646616
FIDELITY to a previously used nesting area has been demonstrated or hypothesized for many bird species (see Greenwood 1980 for partial review). In colonially nesting birds, the area to which a bird returns from one breeding season to the next may be as large, and rela- tively imprecise, as a colony site (colony-site tenacity) or as precise as a specific
The consumption of alcohol among Indians of southeastern North America is examined in this thesis. I discuss and compare the colonial strategies of the Spaniards in La Florida and the English in Carolina. The Spanish colonial strategy focused on converting Indians while English colonial strategy focused on exploiting Indians for economic gain. These differing strategies led to the very different
This work proposes a multi-objective artificial bee colony (MOABC) for optimizing problems with multiple objectives. We have adapted the original Artificial Bee Colony (ABC) algorithm to multi objective problems with a grid-based approach for maintaining and adaptively assessing the Pareto front. The Pareto set is used to control the flying behaviours of the individuals and structuring the bee colony. The
|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,…
Summary Of 38 animal colonies serologically examined for Encephalitozoon cuniculi, 1 mouse, 2 rat and 4 guineapig colonies were positive. A further survey showed that the prevalence within mouse, rat, guinea- pig and rabbit colonies varied between 25 and 95%. Guineapigs housed with infected rabbits are at a greater risk of being infected than those housed separately. Nephritis was a
Sylvatic plague is a major factor influencing prairie dog colony dynamics in the western Great Plains. We studied the nesting response of the mountain plover (Charadrius montanus), a grassland bird that nests on prairie dog colonies, to plague-driven dynamics of prairie dog colonies at three sites i...
The ant colony algorithm is a new class of population basic algorithm. The path planning is realized by the use of ant colony algorithm when the plane executes the low altitude penetration, which provides a new method for the path planning. In the paper the traditional ant colony algorithm is improved, and measures of keeping optimization, adaptively selecting and adaptively
Ant Colony Optimization (ACO) is a meta-heuristic approach inspired by the study of the behavior of real ant colonies when finding the shortest path from their nest to food source. ACO has been used for solving approximately NP-hard problems and its elite effects has been proved by the experiments. Currently, two famous ACO algorithms are Ant Colony System (ACS) and
Scholars of Indian history suggest that the main deterrent to entrepreneurial activity in colonial India was the absolute shortage of capital. A large body of theoretical and empirical research suggests that the key to mobilizing capital is a well functioning financial market. Using various bank records of the colonial state, I determine that the credit markets which supported colonial era
Before the First World War, Belgium participated in a global wave of foreign direct investment. After the war, a shift towards the Belgian colony of the Congo was observed. With regard to these investments, it is commonly argued that higher (expected) profit rates were a strong incentive, although others propose that the colonial powers lost money on their colonial possessions.
Variations in susceptibility to acute oxygen toxicity were observed among animals from the same colony as well as between two different colonies of Sprague-Dawley rats. Animals from Colony I survived, on the average, 6.7 days in 100 per cent oxygen, while...
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
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
This is a retrospective study of the eradication of mouse hepatitis virus (MHV) from two mouse colonies. A breeding colony of SENCAR mice was maintaied in a modified barrier facility. Serum from these mice tested positive for antibodies to MHV and Sendai virus. The colony was reduced to a minimum number, the breeders were separated and all young killed. All
Summary An adenine requiring strain ofCandida albicans, WC-7, forms large smooth colonies. When grown at 37° C under conditions of severe adenine deprivation, WC-7 cultures accumulate variant cells (MR variants) which produce minute, rough colonies. The variants are stable in that they persist upon repeated selective subculturing. However, they do exhibit high rates of reversion to their large, smooth colony
Recently, it has been proposed that the one of the main determinants of complex societies in Hymenoptera is colony size, since the existence of large colonies reduces the direct reproductive success of an average individual, given a decreased chance of being part of the reproductive caste. In this study, we evaluate colony size evolution in corbiculate bees and their relationship
Enrique Rodriguez-Serrano; Oscar Inostroza-Michael; Jorge Avaria-Llautureo; Cristian E. Hernandez
A survey of the temporal pattern of population structure and feeding activity of the seabird tick Ixodesuriae was conducted for the first time in two host species colonies: King penguin (Aptenodytespatagonicushalli) and Macaroni penguin (Eudypteschrysolophuschrysolophus). The life cycle of the tick was investigated over 3 years in a King penguin colony and 2 years in a Macaroni penguin colony at
Y. Frenot; E. de Oliveira; M. Gauthier-Clerc; J. Deunff; A. Bellido; P. Vernon
The rich prehistoric archaeological record in Andean South America has obscured the importance of post-conquest historic sites in the region. Archaeologists researching the former Spanish colonies have long turned to the US ‘Borderlands’ and the Caribbean for models defining the archaeology of Spanish colonialism. Recently, however, Andean archaeologists have begun to create new emphases on the archaeology of colonialism and
European prostitutes occupied an important intermediary status in colonial Bombay’s racially stratified sexual order. In this article, the author offers a transnational feminist analysis of how the colonial state managed its racial and spatial location. The colonial state individuated, fostered, and monitored European prostitutes much more closely than others involved in the sex trade, and “coercive protection” by the police
We assessed the genetic and morphological differences between the two largest breeding colonies of Audouin's Gull Larus audouinii , an endemic seabird species of the Mediterranean region. The two colonies comprise c. 75% of the total world population and are 655 km apart. The Ebro Delta colony was formed recently and, after dramatic growth mainly due to high rates of
Social insect societies are outstanding examples of cooperation and conflict. Individuals work together, yet seek to increase their inclusive fitness at each others' expense. One such conflict is over colony inheritance, when a queen inherits the colony following the death of the previous queen. Colony inheritance is common in the social wasp Polistes dominulus, and it can have dramatic fitness
Thibaud Monnin; Alessandro Cini; Vincent Lecat; Pierre Federici; Claudie Doums
To what extent do colonial public investments continue to influence current regional inequalities in French-speaking West Africa? Using a new database and the spatial discontinuities of colonial investment policy, this paper gives evidence that early colonial investments had large and persistent effects on current outcomes. The nature of investments also matters. Current educational outcomes have been more specifically determined by
The majority of nation-states experienced colonial rule at some point during the last two centuries, with well-studied economic, political, and social consequences after decolonization. This study examines a different form of the colonial legacy, involving the stability of the territorial status quo after independence. We present and test three competing expectations about the colonial legacy, focused around the legitimacy of
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
A method has been developed whereby a very large number of colonies of Escherichia coli carrying different hybrid plasmids can be rapidly screened to determine which hybrid plasmids contain a specified DNA sequence or genes. The colonies to be screened are formed on nitrocellulose filters, and, after a reference set of these colonies has been prepared by replica plating, are
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
Increasing acreage of almonds in California has increased the demand for honey bee colonies for pollination. Since 2005, domestic U.S. colonies have been supplemented with colonies started from package bees imported from Australia. The need for almond pollination in late winter in California fits we...
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.
The lifestyle of wild and laboratory yeast strains significantly differs. In contrast to the smooth colonies of laboratory strains, wild Saccharomyces cerevisiae strains form biofilm-like, strikingly structured colonies possessing distinctive traits enabling them to better survive in hostile environments in the wild. Here, comparing three sets of strains forming differently structured colonies (fluffy, semi-fluffy and smooth), each derived from ancestors
Vratislav Št’oví?ek; Libuše Váchová; Martin Kuthan; Zdena Palková
Summary 1. Simulations of a stochastic, individual-based predictive model were used to invest- igate the ecological processes relating to the formation and growth of colonies (local populations) of Audouin's Gull ( Larus audouinii Payraudeau). A colony was established in 1981 at the Ebro Delta (in the north-western Mediterranean) and since then, the colony has grown dramatically at an average rate
Summary. A shift in colony founding behaviour from single queen (haplometrosis) to multiple queens (pleometrosis) was observed locally in the obligate plant-ant Crematogaster (Decacrema) morphospecies 2, which is associated with Macaranga trees in Borneo. In addition, about a quarter of all mature colonies (27 of 95 trees examined) were found to be multiple queen colonies. They arose either directly from
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
We investigated the relative contribution of the queen and workers to colony nestmate recognition cues and on colony insularity in the Carpenter ant Camponotus fellah . Workers were either individually isolated, preventing contact with both queen and workers (colonial deprived, CD), kept in queenless groups, allowing only worker- worker interactions (queen deprived, QD) or in queenright (QR) groups. Two weeks
Raphael Boulay; Tamar Katzav-Gozansky; Robert K. Vander Meer; Abraham Hefetz
This contribution critically investigates the ideas underpinning the armed struggle of colonial subjects against colonial states in the middle decades of the 20th century. It focuses in particular on two of the most influential texts that inspired and guided violent anti-colonial resistance, The Wretched of the Earth by Frantz Fanon and On Guerrilla Warfare by Mao Zedong. Both Fanon and
A honey bee colony operates as a tightly integrated unit of behavioral action. One manifestation of this in the context of foraging is a colony's ability to adjust its selectivity among nectar sources in relation to its nutritional status. When a colony's food situation is good, it exploits only highly profitable patches of flowers, but when its situation is poor,
A honey bee colony can skillfully choose among nectar sources. It will selectively exploit the most profitable source in an array and will rapidly shift its foraging efforts following changes in the array. How does this colony-level ability emerge from the behavior of individual bees? The answer lies in understanding how bees modulate their colony's rates of recruitment and abandonment
Feeding pollen substitutes to honey bee (Apis mellifera) colonies in kiwifruit (Actinidia deliciosa) orchards had no significant effect on the amount of kiwifruit pollen collected, but caused a decline in the amount of pollen collected from other sources. Pollen substitutes had no significant effect on honey production from colonies used for kiwifruit pollination or colonies managed solely for honey production.
Field observations and laboratory experiments demonstrate that in the Australian meat ant, Iridomyrmex purpureus, the modes of colony founding are remarkably diverse. New colonies can originate from single foundresses (haplometrosis), or foundress associations (pleometrosis), or by colony budding, or the adoption of newly-mated queens that dig founding chambers next to mature nests (probably their natal nests, as workers protect them
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
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,
Andrea C. Highfield; Aliya El Nagar; Luke C. M. Mackinder; Laure M.-L. J. Noel; Matthew J. Hall; Stephen J. Martin; Declan C. Schroeder
A mathematical model of population interactions between Varroa destructor and a honey bee colony is described. The program bases colony population growth on weather conditions, time of year, initial colony population size, queen fecundity, and worker longevity. Varroa population growth is predicte...
The ant colony algorithm of routing technology in a communication network had a broad of applications. The usage of ant colony algorithm to exchange data for distributed databases had not been studied deeply yet. On the purple of solving the dynamic, real-time data exchange problems, the ant colony algorithm model with multi Constraints for routing a data packet was discussed
Inspired by related mechanisms of ant colony and idiotypic network hypothesis, a model of ant colony and immune network is proposed to solve the problem of path planning in a complex environment. The mechanism of stimulation and suppression between antigen and antibody is used to find the path, which solves the complex environment modeling of ant colony algorithm, and improves
Multiple mating by honey bee queens results in colonies of genotypically diverse workers. Recent studies have demonstrated that increased genetic diversity within a honey bee colony increases the variation in the frequency of tasks performed by workers. We show that genotypically diverse colonies, ...
How organisms allocate limited resources to reproduction is critical to their fitness. The size and number of offspring produced have been the focus of many studies. Offspring size affects survival and growth and determines offspring number in the many species where there is a trade-off between size and number. Many social insects reproduce by colony fission, whereby young queens and accompanying workers split off from a colony to form new colonies. The size of a new colony (number of workers) is set at the time of the split, and this may allow fine tuning size to local conditions. Despite the prevalence of colony fission and the ecological importance of social insects, little is known of colony fission except in honey bees. We studied colony fission in the ant Cataglyphis cursor. For clarity, "colony" and "nest" refer to colonies before and after colony fission, respectively (i.e., each colony fissions into several nests). The reproductive effort of colonies was highly variable: Colonies that fissioned varied markedly in size, and many colonies that did not fission were as large as some of the fissioning colonies. The mother queen was replaced in half of the fissioning colonies, which produced 4.0 +/- 1.3 (mean +/- SD) nests of markedly varied size. Larger fissioning colonies produced larger nests but did not produce more nests, and resource allocation among nests was highly biased. When a colony produced several nests and the mother queen was not replaced, the nest containing the mother queen was larger than nests with a young queen. These results show that the pattern of resource allocation differs between C. cursor and honey bees. They also suggest that C. cursor may follow a bet-hedging strategy with regard to both the colony size at which fission occurs and the partitioning of resources among nests. In addition, colony fission may be influenced by the age and/or condition of the mother queen, and the fact that workers allocating resources among nests have incomplete knowledge of the size and number of nests produced. These results show that the process of colony fission is more diverse than currently acknowledged and that studies of additional species are needed. PMID:21870619
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.
A systemic and quantitative study was performed to examine whether different levels of mitotic activities, assessed by the percentage of S-phase cells at any given time point, existed at different physical regions of human embryonic stem (hES) cell colonies at 2, 4, 6 days after cell passaging. Mitotically active cells were identified by the positive incorporation of 5-bromo-2-deoxyuridine (BrdU) within their newly synthesized DNA. Our data indicated that mitotically active cells were often distributed as clusters randomly across the colonies within the examined growth period, presumably resulting from local deposition of newly divided cells. This latter notion was further demonstrated by the confined growth of enhanced green florescence protein (EGFP) expressing cells amongst non-GFP expressing cells. Furthermore, the overall percentage of mitotically active cells remained constantly at about 50% throughout the 6-day culture period, indicating mitotic activities of hES cell cultures were time-independent under current growth conditions.
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.
Microcystis is a toxic colony-forming cyanobacterium, which can bloom in a wide range of freshwater ecosystems. Despite the ecological advantage of the colonial form, few studies have paid attention to the size of Microcystis colonies in the field. With the aim of evaluating the impact of a fluctuating physical environment on the colony size, the genotypic composition and the toxic potential of a Microcystis population, we investigated five different colony size classes of a Microcystis bloom in the Grangent reservoir (France). By sequencing the internal transcribed spacer of the ribosomal operon, we evidenced changes in the genetic structure among size classes in response to environmental change. While similar genotypes were seen in every size class in stable conditions, new dominant genotypes appeared in the smallest colonies (160??m) concomitantly with mixing conditions, strongly suggesting the importance of these colonies in response to disturbances. Moreover, these small colonies played a major role in microcystin production during this bloom, since very high microcystin contents (>?1?pg.cell.(-1)) were found in their cells. These findings indicate that the colony size distribution of a Microcystis population in response to disturbance could be an adaptive strategy that may explain its ecological success in freshwater ecosystems. PMID:24115626
The paper presents an ant colony search algorithm (ACSA)-based approach to solve the unit commitment (UC) problem. This ACSA algorithm is a relatively new meta-heuristic for solving hard combinatorial optimization problems. It is a population-based approach that uses exploitation of positive feedback, distributed computation as well as a constructive greedy heuristic. Positive feedback is for fast discovery of good solutions,
The ant colony optimization (ACO) algorithm is a fast suboptimal meta-heuristic based on the behavior of a set of ants that\\u000a communicate through the deposit of pheromone. It involves a node choice probability which is a function of pheromone strength\\u000a and inter-node distance to construct a path through a node-arc graph. The algorithm allows fast near optimal solutions to\\u000a be
Ant Colony Optimization (ACO) has become quite popular in recent years. In contrast to many successful applications, the theoretical\\u000a foundation of this randomized search heuristic is rather weak. Building up such a theory is demanded to understand how these\\u000a heuristics work as well as to come up with better algorithms for certain problems. Up to now, only convergence results have
This paper introduces ant colony system (ACS), a distributed algorithm that is applied to the Stable Marriage Problem (SM).\\u000a The stable marriage problem is an extensively-studied combinatorial problem with many practical applications. It is well known\\u000a that at least one stable matching exists for every stable marriage instance. However, the classical Gale-Shapley  algorithm\\u000a produces a marriage that greatly favors
In the 5 years since granulocyte-macrophage colony-stimulating factor (GM-CSF) was first tested clinically, a number of different strategies for its use have been evaluated in patients with malignant disease. These include using GM-CSF to support standard and high-dose chemotherapy, to accelerate myeloid reconstitution following marrow transplantation, to mobilize peripheral blood progenitor cells into the circulation for harvesting and transplantation, and
Abstract Small colony variants (SCVs) are subpopulations of a bacterial strain that differ in morphology, growth rate, metabolism, and antibiotic sensitivity from the parent line. They are associated with chronic and difficult-to-treat infections. SCV endocarditis is very rare and usually associated with intracardiac devices. Herein, we report a case of endocarditis caused by SCV-forming Enterococcus faecalis that affected the native heart without any known predisposition. PMID:23808721
Feature selection is an important step in many pattern recognition systems that aims to overcome the so-called curse of dimensionality\\u000a problem. Although Ant Colony Optimization (ACO) proved to be a powerful technique in different optimization problems, but\\u000a it still needs some improvements when applied to the feature selection problem. This is due to the fact that it builds its\\u000a solutions
Rami N. Khushaba; Ahmed Al-ani; Akram Alsukker; Adel Al-jumaily
The first permanent European settlers of Australia arrived in 1788 to establish a penal colony at Sydney, New South Wales (NSW). As the colony grew and wool production increased, more free settlers and emancipists developed farming in inland Australia. During the 1840s veterinarians commenced arriving in small numbers but they were not closely associated with the development and execution of disease control programs, which was left to lay inspectors of stock. The arrival of William Tyson Kendall and coordinated action with Graham Mitchell led to the establishment of a private veterinary college following the passage of veterinary surgeons legislation in Victoria. From this time, veterinarians came to be appointed to positions formerly occupied by lay inspectors and the veterinary profession was able to take up the role of planning and executing government-led disease control programs. From a colony relying on wool for export to the UK, technical advancements in meat freezing and pasture improvement widened the range and increased the quantity of exported products. Before the advent of veterinary advances, sheep scab was eradicated, a vaccine was developed for anthrax and glanders infection of horses was prevented entry to Australia. Graduates from the Melbourne Veterinary College spread across Australia and in this period a conservative quarantine policy was developed following inaction to control an outbreak of contagious bovine pleuropneumonia (CBPP) and the escape of rabbits to form a plague across the continent. Coordinated control of CBPP had to await the next century and advancement of technology increased our understanding of bacteriology and immunity of infectious diseases. Veterinary services were provided to the militia sent by the colonies to the Boer Wars in South Africa 1987-1901 and the veterinarians from Victoria were led by an Australian trained veterinarian. PMID:21696369
The flow of jelly from 100 nurse bees to the members of two normal-sized colonies was measured during one night. To follow the flow, nurses were injected with 14C-phenylalanine. They incorporated this label into the protein of their hypopharyngeal (brood food) glands and their own body protein. When they were allowed trophallactic contacts during the investigation period a loss of
Honeybee nurses (8 days old) were injected with 14C-phenylalanine. These bees then dispensed the 14C-labelled protein-rich products of their hypopharyngeal glands to the queen and the brood, and also to young drones and workers of all age classes. In small colonies containing 400–800 bees, nearly one-quarter of the radioactivity which could not be recovered in the nurses was fed by
Germ cell sequestering in Animalia is enlightened by either, launching true germ line along epigenetic or preformistic modes of development, or by somatic embryogenesis, where no true germ line is set aside. The research on germ line-somatic tissue segregation is of special relevancy to colonial organisms like botryllid ascidians that reconstruct, on a weekly basis, completely new sets of male and female gonads in newly formed somatic tissues. By sequencing and evaluating expression patterns of BS-Vasa, the Botryllus schlosseri orthologue of Vasa, in sexually mature and asexual colonies during blastogenesis, we have demonstrated that the BS-Vasa mRNA and protein are not expressed exclusively in germ cell lineages, but appeared in cells repeatedly emerging de novo in the colony, independently of its sexual state. In addition, we recorded an immediate Vasa response to cellular stress (UV irradiation) indicating additional functions to its germ line assignments. To confirm germ lineage exclusivity, we examined the expression of three more stem cell markers (BS-Pl10, Bl-piwi and Oct4). Vasa co-expression with Pl10 and Oct4 was detected in germ line derivatives and with Bl-piwi in somatic tissues. Presumptive primordial germ cells (PGC-like cells), that are Vasa(+)/Pl10(+)/Oct4(+) and 6-12 microm in diameter, were first detected in wrapped-tail embryos, in oozooids, in sexual/asexual colonies, within a newly identified PGC niche termed as 'budlet niche', and in circulating blood borne cells, indicating epigenetic embryogenesis. Alternatively, BS-Vasa co-expression with piwi orthologue, an omnipresent bona fide stemness flag, in non germ line cell populations, may indicate germ cell neogenesis (somatic embryogenesis) in B. schlosseri. Both alternatives are not necessarily mutually exclusive. PMID:19406116
Just after the Emancipation Proclamation went into effect (1 Jan 1863) Abraham Lincoln signed a contract with two New York capitalists to transport 500 newly-freed ex-slaves to Ile-a-Vache, Haiti, where they would, under company supervision, found and maintain a colony. From the start, little went right. Failure was due largely to mismanagement and chicanery on the part of the company.
The $$\\\\epsilon$$-Depth ANT Explorer ($$\\\\epsilon$$-\\u000a DANTE\\u000a ) algorithm applied to a multiple objective optimization problem is presented in this paper. This method is a hybridization\\u000a of the ant colony optimization algorithm with a depth search procedure, putting together an oriented\\/limited depth search.\\u000a A particular design of the pheromone set of rules is suggested for these kinds of optimization problems, which
Microfermentation tests for members of the family Enterobacteriaceae were devised by using agar solutions in disposable, multi-welled, plastic trays. The tests could be made directly from isolated colonies picked from agar plates and represented a considerable saving in time, labor, and materials over the conventional methods. Tests were formulated for determining carbohydrate fermentations, citrate utilization, motility, amino acid decarboxylation, and production of H2S, indole, urease, and acetyl-methyl-carbinol.
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
Routes planning is one of the most important aspects in emergency evacuation planning. A multi-objective emergency evacuation model using ant colony optimization was proposed for routes planning in complex multi-exit evacuation environment. The two objectives of the model are to minimize the total evacuation time of all evacuees and to minimize the total path crowding degree respectively. A multi-objective ant
Xinlu Zong; Shengwu Xiong; Zhixiang Fang; Wanru Lin
1.Worker honeybees contacting a queen can transport the queen's inhibitory signal, queen substance, to other workers unable to contact the queen. Airborne dispersal of queen substance is at most a minor mechanism for queen substance transmission.2.This worker transport of queen substance is an important supplement to queen substance dispersal by direct queen-worker contacts. For although colonies lose their inhibition against
In addition to honeybee workers, drones also contribute to colonial thermoregulation. We show the drones’ contribution to\\u000a thermoregulation at 5 different experimental temperatures ranging from 15– 34 °C. The frequency and the degree of endothermy\\u000a depended on the drones’ local ambient temperature and age. Location on brood or non-brood areas had no influence. The frequency\\u000a of endothermic drones and the
Helmut Kovac; Anton Stabentheiner; Robert Brodschneider
Ant Colony Optimisation (ACO) is an effective population-based meta-heuristic\\u000afor the solution of a wide variety of problems. As a population-based\\u000aalgorithm, its computation is intrinsically massively parallel, and it is\\u000athere- fore theoretically well-suited for implementation on Graphics Processing\\u000aUnits (GPUs). The ACO algorithm comprises two main stages: Tour construction\\u000aand Pheromone update. The former has been previously implemented
José M. Cecilia; José M. García; Manuel Ujaldon; Andy Nisbet; Martyn Amos
The microorganisms capable of producing opportunist infections include the yeast-like organisms of the genus Candida, and\\u000a the unicellular algae of the genus Prototheca, which share common features and can, therefore, lead to confusion. Their colonies\\u000a are almost identical and they grow in the same culture media used routinely in mycology.\\u000a \\u000a CHROMagar Candida is a new chromogenic differential isolation medium that
Manuel Casal; María José Linares; Francisco Solís; Fernando C. Rodríguez
The ‘benefits of philopatry’ hypothesis states that helpers in cooperatively breeding species derive higher benefits from\\u000a remaining home, instead of dispersing and attempting to breed independently. We tested experimentally whether dispersal options\\u000a influence dispersal propensity in the cooperatively breeding Lake Tanganyika cichlids Neolamprologus pulcher and N. savoryi. Cooperative groups of these fishes breed in densely packed colonies, surrounded by unoccupied,
Ant colony optimisation is a constructive metaheuristic that successively builds solutions from problem-specic components. A pa- rameterised model known as pheromone|an analogue of the trail phero- mones used by real ants|is used to learn which components should be combined to produce good solutions. In the majority of the algorithm's applications a single parameter from the model is used to inuence
The Ant Colony Optimization (ACO) algorithms are being applied successfully to a wide range of problems. ACO algorithms could\\u000a be good alternatives to existing algorithms for hard combinatorial optimization problems (COPs). In this paper we investigate\\u000a the influence of the probabilistic model in model-based search as ACO. We present the effect of four different probabilistic\\u000a models for ACO algorithms to
The mechanisms operating in the formation and maintenance of colony odor in the ponerine ant Pachycondyla apicalis were studied using radioactive tracers. Using [l-14C]acetate as a precursor, the de novo biosynthesis and distribution of pentane-extractable lipids within the ant's body were followed. Twenty-four hours after injection, newly synthesized alkanes, alkenes, as well as more polar lipids were found in the
Victoria Soroker; Dominique Fresneau; Abraham Hefetz
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,
This paper situates the current abortion practice and policy in Puerto Rico within the historical, political, and economic context of the colonial domination of the United States (US) over Puerto Rico. In particular, we pay attention to the hurdles that women face to obtain abortion services in Puerto Rico as a result of its colonial legality. Of particular significance is the overall low abortion ratio, and differential abortion ratio and access issues faced by women when grouped by an age-ethnicity category: unmarried teenagers, adult Puerto Rican women and, adult immigrant women from the Dominican Republic. The present hurdles to abortion access--related to information, abortion providers, economic situation, and government policies--are discussed within the colonial legality of abortion based on the US Supreme Court decision Roe v. Wade. Puerto Rico's case is situated within its broader history of population policies developed by the State since the 1930's. Of particular relevance is the antagonism that State managers have had towards abortion in spite of its legality. In this sense, abortion in Puerto Rico continues to be an unfinished business, in spite of its legality. PMID:9642718
The AOAC International official action procedure for performing aerobic colony counts on hydrophobic grid membrane filters (HGMFs) uses Trypticase soy-fast green FCF agar (FGA) incubated for 48 h. Microbial growths are various shades of green on a pale green background, which can cause problems for automated as well as manual counting. HGMFs which had been incubated 24 or 48 h at 35°C on Trypticase soy agar were flooded underneath with 1 to 2 ml of 0.1% triphenyltetrazolium chloride (TTC) solution by simply lifting one corner of the filter while it was still on the agar and adding the reagent. Microbial growths on HGMFs were counted after color had been allowed to develop for 15 min at room temperature. With representative foods, virtually all colonies stained pink to red. Automated electronic counts made by using the MI-100 HGMF Interpreter were easier and more reliable than control HGMF counts made by the AOAC International official action procedure. Manual counting was easier as well because of increased visibility of the microbial growths. Except in the case of dairy products, 24-h TTC counts did not differ significantly from 48-h FGA counts, whereas the FGA counts at 24 h were always significantly lower, indicating that for many food products the HGMF TTC flooding method permits aerobic colony counts to be made after 24 h.
Parrington, Lorna J.; Sharpe, Anthony N.; Peterkin, Pearl I.
Studies of avian host-parasite interactions rarely include consequences of relationships among hosts for either the host or parasite species. In this study, we examine the ectoparasitic burden of adult and nestling European bee-eaters (Merops apiaster) and rock sparrows (Petronia petronia) in a mixed colony. We found that (1) each bird species had its own species of lice; (2) hematophagous mites parasitized both adults and nestlings of both bird species; (3) Carnus hemapterus, a common parasite of nestling bee-eaters, also infested rock sparrow nestlings, a species not previously described as a host for this dipteran; and (4) whereas C. hemapterus did not show high host specificity within the colony, the emergence of adult flies was synchronized with the start of hatching in bee-eater nests. We suggest that coexistence of these 2 bird species results in parasite exchange, bee-eaters obtaining mites from sparrows and sparrows becoming infested by C. hemapterus. Differences in the detrimental effects of parasite transfer for each host species may result in a process of apparent competition mediated by shared parasites. Interspecific parasite exchange is an important aspect of host-parasite relationships in mixed colonies, which requires further attention. PMID:12760636
Valera, Francisco; Casas-Crivillé, Alejandro; Hoi, Herbert
The enteric bacterium Proteus mirabilis, which is a pathogen that forms biofilms in vivo, can swarm over hard surfaces and form a variety of spatial patterns in colonies. Colony formation involves two distinct cell types: swarmer cells that dominate near the surface and the leading edge, and swimmer cells that prefer a less viscous medium, but the mechanisms underlying pattern formation are not understood. New experimental investigations reported here show that swimmer cells in the center of the colony stream inward toward the inoculation site and in the process form many complex patterns, including radial and spiral streams, in addition to previously-reported concentric rings. These new observations suggest that swimmers are motile and that indirect interactions between them are essential in the pattern formation. To explain these observations we develop a hybrid model comprising cell-based and continuum components that incorporates a chemotactic response of swimmers to a chemical they produce. The model predicts that formation of radial streams can be explained as the modulation of the local attractant concentration by the cells, and that the chirality of the spiral streams results from a swimming bias of the cells near the surface of the substrate. The spatial patterns generated from the model are in qualitative agreement with the experimental observations.
Organisms should invest more in gathering information when the pay-off from finding a profitable resource is likely to be greater. Here, we ask whether animal societies put more effort in scouting for a new nest when their current one is of low quality. We measured the scouting behaviour of Temnothorax albipennis ant colonies when they inhabit nest-sites with different combinations of desirable attributes. We show that the average probability of an ant scouting decreases significantly with an increase in the quality of the nest in which the colony currently resides. This means that the greater the potential gain from finding a new nest, the more effort a colony puts into gathering information regarding new nest-sites. Our results show, for the first time to our knowledge, the ability of animal societies to respond collectively to the quality of a resource they currently have at their disposal (e.g. current nest-site) and regulate appropriately their information gathering efforts for finding an alternative (e.g. a potentially better nest-site). PMID:24088565
Doran, Carolina; Pearce, Tom; Connor, Aaron; Schlegel, Thomas; Franklin, Elizabeth; Sendova-Franks, Ana B; Franks, Nigel R
In the province of Chaco, Argentina, there is a very unique dispersion of metallic meteorites called ``Campo del Cielo''. One of the meteoric fragments of this dispersion, the meteorite called ``El Chaco'', consisting of 37 tons, is the second heaviest in the world. These meteorites are of great importance to the worldview of the Moqoit, aboriginal people that inhabit this region. For the local Creole population the meteorites are also relevant, that's why they have being cited in numerous documents and reports since the colonial period. During the first months of 2012, two Argentine artists and the Artistic Director of the German contemporary art exhibition called dOCUMENTA (13) tried to move ``El Chaco'' meteorite to Germany in order to exhibit it as an artistic object. Due to the fact that moving the meteorite could have a negative impact according to the Moqoit cosmology and that they were not able to participate in the decision they begun a manifestation against the movement of El Chaco. The opposition made by aboriginal communities and experts in cultural astronomy was able to stop the transfer. The whole process and its impact on the local community have promoted a deep discussion about art, science and cultural colonialism. In this paper we aim to address this debate and its consequences. This will allow us to think about contemporary forms of colonialism that are hidden in many scientific and artistic projects. Furthermore, we aim to debate about the most effective ways of protecting astronomical heritage in the Third World.
The colony and population structure of the carpenter ant, Camponotus floridanus, were investigated by multilocus DNA fingerprinting using simple repeat motifs as probes [e.g. (GATA)4]. The mating frequency of 15 queens was determined by comparing the fingerprint patterns of the queen and 17-33 of her progeny workers. C. floridanus queens are most probably singly mated, i.e. this species is monandrous and monogynous (one queen per colony). C. floridanus occurs in all counties of mainland Florida and also inhabits most of the Key islands in the southern part of Florida. We tested whether the two mainland populations and the island populations are genetically isolated. Wright's FST and Nei's D-value of genetic distance were calculated from intercolonial bandsharing-coefficients. The population of C. floridanus is substructured (FST = 0.19 +/- 0.09) and the highest degree of genetic distance was found between one of the mainland populations and the island populations (D = 0.35). Our fingerprinting technique could successfully be transferred to 12 other Camponotus species and here also revealed sufficient variability to analyse the genetic structure. In three of these species (C. ligniperdus, C. herculeanus and C. gigas) we could determine the mating frequency of the queen in one or two colonies, respectively. PMID:8981768
Recent work has demonstrated considerable benefits of intracolonial genetic diversity for the productivity of honeybee colonies: single-patriline colonies have depressed foraging rates, smaller food stores and slower weight gain relative to multiple-patriline colonies. We explored whether differences in the use of foraging-related communication behaviour (waggle dances and shaking signals) underlie differences in foraging effort of genetically diverse and genetically uniform colonies. We created three pairs of colonies; each pair had one colony headed by a multiply mated queen (inseminated by 15 drones) and one colony headed by a singly mated queen. For each pair, we monitored the production of foraging-related signals over the course of 3 days. Foragers in genetically diverse colonies had substantially more information available to them about food resources than foragers in uniform colonies. On average, in genetically diverse colonies compared with genetically uniform colonies, 36% more waggle dances were identified daily, dancers performed 62% more waggle runs per dance, foragers reported food discoveries that were farther from the nest and 91% more shaking signals were exchanged among workers each morning prior to foraging. Extreme polyandry by honeybee queens enhances the production of worker-worker communication signals that facilitate the swift discovery and exploitation of food resources. PMID:18198143
Mattila, Heather R; Burke, Kelly M; Seeley, Thomas D
The sub-discipline of Historical Archaeology continues to push out its borders from its origins as the archaeology of British\\u000a colonial settlement in North America. This review article evaluates the contribution of a set of papers presented at the Society\\u000a of Historical Archaeology meeting in Albuquerque New Mexico in early 2008, and shows how new theoretical formulations are\\u000a taking shape.
We describe a case of a spontaneously established mixed colony of two species of stingless bees. The host colony of Scaptotrigona depilis, an aggressive bee that forms large colonies, was invaded by workers of Nannotrigona testaceicornis, a smaller bee that forms small colonies. The host colony and the invading species colony were maintained in next boxes about 1.5 m apart. The N. testaceicornis colony had been recently divided. Observations were made daily for 10 min, and every two weeks the colony was opened for observations within the nest. Initially the host colony bees repulsed the invading species, but as their numbers built up, they were no longer able to defend the entrance. An estimated 60-90 N. testaceicornis workers lived integrated into the colony of S. depilis for 58 days. During this period, they reconstructed and maintained the entrance tube, changing it to an entrance typical of N. testaceicornis. They also collected food and building material for the host colony. Nannotrigona testaceicornis tolerated transit of S. depilis through the entrance, but did not allow the host species to remain within the tube, though the attacks never resulted in bee mortality. Aggression was limited to biting the wings; when the bees fell to the ground they immediately separated and flew back. There have been very few reports of spontaneously occurring mixed stingless bee colonies. It is difficult to determine what caused the association that we found; probably workers of N. testaceicornis got lost when we split their colony, and then they invaded the colony of S. depilis. PMID:19551639
This study tested the hypothesis that corals of the same species, but of varying size and shape, may respond differently to thermal stress because of different mass transfer capacities. High mass transfer rates are an advantage under thermal stress, and mass transfer rates are assumed to scale with size. Yet large, corymbose Acropora colonies are more vulnerable to thermal stress than small corymbose Acropora colonies. We took a two-tiered approach to examine the differences in the susceptibility of different coral morphologies to thermal stress. Firstly, the response of several coral species of different sizes and shapes were measured in the field through a thermal stress event. Secondly, diffusion experiments were conducted using gypsum-coral models of different morphologies to estimate mass transfer rates, to test whether dissolution rates differed in accordance with colony morphology and colony size. Coral colonies with a high height to diameter ratio were subjected to more partial mortality than flat colonies. These results agree with mass transfer theory. The diffusion experiments showed that in a low-flow environment, small encrusting colonies had higher rates of dissolution than large flat or small branched colonies. These results, however, disagree with mass transfer theory. We show that the volume of space between colony branches predicts the response to thermal stress in the field. Small encrusting colonies were most likely to maintain mass transfer and were therefore more likely to survive thermal stress than large branched colonies. We predict that an increase in the frequency and intensity of thermal stresses may see a shift from large branched coral colonies to both small colonies, and flat-massive colonies with low aspect ratios.
van Woesik, R.; Irikawa, A.; Anzai, R.; Nakamura, T.
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.
We studied possible host finding and resistance mechanisms of host colonies in the context of social parasitism by Cape honeybee (Apis mellifera capensis) workers. Workers often join neighboring colonies by drifting, but long-range drifting (dispersal) to colonies far away from the maternal nests also rarely occurs. We tested the impact of queenstate and taxon of mother and host colonies on
Peter Neumann; Sarah E. Radloff; Robin F. A. Moritz; H. Randall Hepburn; Sacha L. Reecea
The study of hematopoietic colony-forming units using semisolid culture media has greatly advanced the knowledge of hematopoiesis. Here we report that similar methods can be used to study pancreatic colony-forming units. We have developed two pancreatic colony assays that enable quantitative and functional analyses of progenitor-like cells isolated from dissociated adult (2–4 mo old) murine pancreas. We find that a methylcellulose-based semisolid medium containing Matrigel allows growth of duct-like “Ring/Dense” colonies from a rare (?1%) population of total pancreatic single cells. With the addition of roof plate-specific spondin 1, a wingless-int agonist, Ring/Dense colony-forming cells can be expanded more than 100,000-fold when serially dissociated and replated in the presence of Matrigel. When cells grown in Matrigel are then transferred to a Matrigel-free semisolid medium with a unique laminin-based hydrogel, some cells grow and differentiate into another type of colony, which we name “Endocrine/Acinar.” These Endocrine/Acinar colonies are comprised mostly of endocrine- and acinar-like cells, as ascertained by RNA expression analysis, immunohistochemistry, and electron microscopy. Most Endocrine/Acinar colonies contain beta-like cells that secrete insulin/C-peptide in response to D-glucose and theophylline. These results demonstrate robust self-renewal and differentiation of adult Ring/Dense colony-forming units in vitro and suggest an approach to producing beta-like cells for cell replacement of type 1 diabetes. The methods described, which include microfluidic expression analysis of single cells and colonies, should also advance study of pancreas development and pancreatic progenitor cells.
Jin, Liang; Feng, Tao; Shih, Hung Ping; Zerda, Ricardo; Luo, Angela; Hsu, Jasper; Mahdavi, Alborz; Sander, Maike; Tirrell, David A.; Riggs, Arthur D.; Ku, Hsun Teresa
During cheese ripening, micro-organisms grow as immobilised colonies, metabolising substrates present in the matrix which generate products triggered by enzymatic reactions. Local limitation rates of diffusion, either in the matrix or within the bacterial colonies, can be responsible for modulation in the metabolic and enzymatic activities of micro-organisms during ripening. How bacterial colonies immobilised in cheese are porous to these diffusing solutes has never been explored. The objective of this study was to determine if fluorescent dextrans of different sizes (4.4, 70 and 155 kDa) are able to penetrate through colonies of Lactococcus lactis LD61 immobilised in solid media, either agar or model cheese. Confocal microscopic observations showed that lactococcus colonies immobilised in these two media were porous to dextrans from 4 kDa to 155 kDa. However, the rate of diffusion of the solutes was faster inside the colonies immobilised in ultrafiltered-cheese than in agar when large dextrans were considered (?70 kDa). The colonial shape of the lactococcus strain was also shown to be lenticular in agar and spherical in the model cheese, indicating that the physical pressure exerted on the colony by the surrounding casein network was probably isotropous in the UF-cheese but not in agar. In both cases, the fact that lactococcus colonies immobilised in solid media are porous to large dextran solutes suggests that substrates or enzymes are likely also to be able to migrate inside the colonies during cheese ripening. PMID:23558188
Weaver ants (Oecophylla smaragdina) are dominant ants in open forests from India, Australia, China and Southeast Asia, whose leaf nests are held together with larval silk. The species, together with its sole congener O. longinoda, has been important in research on biological control, communication, territoriality and colony integration. Over most of the range, only one queen has been found per colony, but the occurrence of several queens per nest has been reported for the Australian Northern Territory. The number of males mating with each queen is little known. Here we report on the colony structure of O. smaragdina using published and new microsatellite markers. Worker genotype arrays reflect the occurrence of habitual polygyny (more than one queen per colony) in 18 colonies from Darwin, Northern Australia, with up to five queens inferred per colony. Monogyny (one queen per colony) with occasional polygyny was inferred for 14 colonies from Queensland, Australia, and 20 colonies from Java, Indonesia. Direct genotyping of the sperm carried by 77 Queensland queens and worker genotypic arrays of established colonies yielded similar results, indicating that less than half of the queens mate only once and some mate up to five times. Worker genotype arrays indicated that queens from Java and the Northern Territory also often mate with more than one male, but less often than those from Queensland. A strong isolation-by-distance effect was found for Queensland samples. The variation uncovered means that O. smaragdina is a more versatile study system than previously supposed. PMID:19076274
Schlüns, E A; Wegener, B J; Schlüns, H; Azuma, N; Robson, S K A; Crozier, R H
A simple technique for determining hydrophobic-hydrophilic properties of bacterial colonies surface, which involves putting a drop of liquid with known properties (e.g. water, oil) on their surface, has been described. This technique allows quick estimate of wettability of bacterial colony surface, i.e. its hydrophobic-hydrophilic properties. The behaviour of water drops on colonies of bacteria Bacillus five strains (of different types) has been studied. It was revealed that 1) orientation in the Earth gravity field during bacterial growth can define the form of colonies with hydrophobic surface; 2) the form and size of the colony are dependent on the extention ability, most probably, of the hydrophobic layer; 3) the Earth gravity field (gravity) serves as a 'pump' providing and keeping water within the colony. We suppose that at growing colonies on agar media the inflow of water-soluble nutrient materials takes place both due to diffusion processes and directed water current produced by the gravity. The revealed effect probably should be taken into consideration while constructing the models of colonies growing on dense nutrient media. The easily determined hydrophobic properties of colonies surface can become a systematic feature after collecting more extensive data on the surface hydrophobic-hydrophilic properties of microorganism colonies of other types and species.
Puzyr, A. P.; Tirranen, L. K.; Krylova, T. Y.; Borodina, E. V.
In September of 2010, Brewer's Bay reef, located in St. Thomas (U.S. Virgin Islands), was simultaneously affected by abnormally high temperatures and the passage of a hurricane that resulted in the mass bleaching and fragmentation of its coral community. An outbreak of a rapid tissue loss disease among coral colonies was associated with these two disturbances. Gross lesion signs and lesion progression rates indicated that the disease was most similar to the Caribbean coral disease white plague type 1. Experiments indicated that the disease was transmissible through direct contact between colonies, and five-meter radial transects showed a clustered spatial distribution of disease, with diseased colonies being concentrated within the first meter of other diseased colonies. Disease prevalence and the extent to which colonies were bleached were both significantly higher on unattached colony fragments than on attached colonies, and disease occurred primarily on fragments found in direct contact with sediment. In contrast to other recent studies, disease presence was not related to the extent of bleaching on colonies. The results of this study suggest that colony fragmentation and contact with sediment played primary roles in the initial appearance of disease, but that the disease was capable of spreading among colonies, which suggests secondary transmission is possible through some other, unidentified mechanism. PMID:23437335
Brandt, Marilyn E; Smith, Tyler B; Correa, Adrienne M S; Vega-Thurber, Rebecca
Two juvenile hormone analogs (JHAs), pyriproxyfen and S-methoprene, were impregnated into dried tuna fish and fed to colonies of Monomorium pharaonis (L.) at very low concentrations (1.0, 2.0, 3.0, 4.0, and 5.0 microg/ml). Its effects on the production of sexuals and colonial growth were observed. Colonies treated with pyriproxyfen yielded sexuals with physical abnormalities. Both female and male sexuals developed bulbous wings, decreased melanization, and died shortly after emergence. Sexuals emerged from colonies treated with S-methoprene did not possess anomalous characteristics. Both pyriproxyfen and S-methoprene did not have significant effects on colonial growth because of the low concentrations of the baits. A commercial bait containing 0.3% S-methoprene (Bioprene-BM) also was evaluated for its efficacy on Pharaoh's ant colonies. Results showed that Pharaoh's ant colonies succumbed to the lethal effects of S-methoprene. Colony members were reduced significantly. Production of queens also decreased significantly in treated colonies and treated queens were unable to lay eggs. JHAs are slow acting and eliminate ant colonies at a relatively slow rate. At low concentrations, pyriproxyfen recorded baffling results, i.e., bulbous wings and demelanized exoskeleton, and it is vital that further studies are initiated to solidify these findings. PMID:16539147
Colonial policies and practices were very instrumental in the creation of the Luo Diaspora. This Diaspora extended far beyond the physical and cultural boundaries of Central Nyanza as was constituted by the colonial administration. To colonial officials, this Diaspora represented "detribalized natives" responsible for social decay and immorality in the colonial townships. Similarly, to the male elders in the rural areas, this Diaspora was an affront towards destabilizing tribal authority and sanctions, which governed Luo moral order, Luo marriage, and Luo identity as it existed prior to colonialism. This article uses patriarchy as an analytical framework to understand how male elders and colonial officials collaborated to assert control over young women under suspicion of prostitution. The article argues that the Ramogi African Welfare Association (RAWA) was a post-war patriarchal institution which was used by male elders, with the encouragement of the colonial officials, to intimidate, harass and repatriate young women seeking wage employment within the emerging colonial townships. In this article, I use archival and field data gathered from Central Nyanza between 1999 and 2002 to illustrate how institutionalized patriarchy threatened many women and young girls seeking to migrate to colonial towns in order to exploit the limited economic and social opportunities that colonialism provided. PMID:20976983
Human embryonic stem cells (hESCs) self-renew indefinitely as highly organized pluripotent colonies. Unlike mouse pluripotent stem cell colonies, human colonies form a uniform, flat, epithelium-like monolayer. Interestingly, it has been reported that colony morphology is closely correlated with the maintenance of pluripotency. However, the molecular mechanisms that underlie human pluripotent colony formation and organization are poorly understood. In this study, we used real-time imaging tools to examine the in vitro colony formation of enzymatically dissociated single hESCs under feeder-free conditions. We demonstrate that colony formation consists of 4 stages: attachment, migration, aggregation, and colony formation, which are facilitated in an intracellular, calcium-dependent manner. Moreover, we found that blocking G(i)-coupled G protein-coupled receptor (GPCR) signaling results in enhanced cell-cell interactions and plays an integral role in promoting the survival of hESCs in culture. From the imaging results, we identified the conditions required for colony formation, and we identified the importance of blocking G(i)-coupled GPCR by pertussis toxin in modulating hESC colony formation and organization. These results will likely be useful for engineering hESCs to further study the mechanisms involved in their function. PMID:23075100
Kim, Jung Mo; Moon, Sung-Hwan; Park, Soon-Jung; Lee, Ha Young; Hong, Ki-Sung; Seo, Joseph; Bae, Yoe-Sik; Chung, Hyung-Min
The lifestyle of wild and laboratory yeast strains significantly differs. In contrast to the smooth colonies of laboratory strains, wild Saccharomyces cerevisiae strains form biofilm-like, strikingly structured colonies possessing distinctive traits enabling them to better survive in hostile environments in the wild. Here, comparing three sets of strains forming differently structured colonies (fluffy, semi-fluffy and smooth), each derived from ancestors with distinct genetic backgrounds isolated from natural settings (BR-88, BR-99 and BR-103), we specified the factors essential for the formation of structured colonies, i.e. for the lifestyle most likely to be preferred in the wild. The ability to form an abundant extracellular matrix (ECM) is one of the features typical for structured colonies. ECM influences colony architecture and many other physiological properties, such as the capability to retain water in a 2-fold surplus to wet cell biomass. ECM composition, however, differs among distinct strains, depending on their particular genetic background. We further show that the expression of certain genes (AQY1, FLO11) is also strictly related to the particular colony morphology, being highest in the most structured colonies. Flo11p adhesin, important for cell-cell and cell-surface adhesion, is essential for the formation of fluffy colonies and thus significantly contributes to the phenotype variability of wild yeast strains. On the other hand, surprisingly, neither the cell shape nor budding pattern nor the ability to form pseudohyphae directly influences the formation of three-dimensional fluffy colony architecture. PMID:20728557
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
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
\\u000a This paper presents an improvement ant colony optimization algorithm for mining classification rule called ACO-Miner. The\\u000a goal of ACO-Miner is to effectively provide intelligible classification rules which have higher predictive accuracy and simpler\\u000a rule list based on Ant-Miner. Experiments on data sets from UCI data set repository were made to compare the performance of\\u000a ACO-Miner with Ant-Miner. The results show
This article describes a new method of studying climate change. A previously unnoticed cooling trend that persisted for a millennium caused enough ice to build up in Antarctica's Ross Sea that thousands of Adelie penguins abandoned their colonies beginning about 2,000 years ago. The techniques may also help to refine our understanding of climatic change on the southernmost continent. This article is enhanced by a video and photographs and the site offers links to more information including a version of the original paper.
A new continuum model for the growth of a single species biofilm is proposed. The geometry of the biofilm is described by the interface between the biomass and the surrounding liquid. Nutrient transport is given by the solution of a semi-linear Poisson equation. In this model we study the morphology of a chemotactic bacterial colony, which grows in the direction of increasing nutrient concentration. Numerical simulations using the level set method and finite difference schemes are presented. The results show rich heterogeneous morphology. PMID:15303740
Alpkvist, E; Overgaard, N Chr; Gustafsson, S; Heyden, A
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.
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
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
This paper presents a summary of accomplishments at the Colonie FUSRAP Site in Fiscal Year 2002. During this period several significant milestones were achieved and have set the stage for the project to be completed in a more comprehensive manner, ahead of schedule and at a lower cost than the original Remedial Plan inherited from the Dept of Energy in 1997. Discussion of the DOE and subsequent USACE remedial plans is included along with summary level discussions of the key site infrastructure and remedial elements.
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.