2,552 research outputs found
Black holes and neutron stars in the generalized tensor-vector-scalar theory
Bekenstein's Tensor-Vector-Scalar (TeVeS) theory has had considerable success
as a relativistic theory of Modified Newtonian Dynamics (MoND). However, recent
work suggests that the dynamics of the theory are fundamentally flawed and
numerous authors have subsequently begun to consider a generalization of TeVeS
where the vector field is given by an Einstein-Aether action. Herein, I develop
strong-field solutions of the generalized TeVeS theory, in particular exploring
neutron stars as well as neutral and charged black holes. I find that the
solutions are identical to the neutron star and black hole solutions of the
original TeVeS theory, given a mapping between the parameters of the two
theories, and hence provide constraints on these values of the coupling
constants. I discuss the consequences of these results in detail including the
stability of such spacetimes as well as generalizations to more complicated
geometries.Comment: Accepted for publication in Physical Review
Further strategies for evaluating the etiological role of a tumor-associated herpesvirus in marine turtle fibropapillomatosis
In 1992, an interdisciplinary research team headquartered at the University of Florida
began studies in key targeted areas of fibropapillomatosis (FP) etiology and
pathogenesis. At that time, little was known about FP outside of field studies
documenting its prevalence in different areas of the world and studies of tumor
histopathology. Our primary objective was to develop a broad-based scientific
understanding of FP by applying principles of tumor biology, immunology, pathology,
virology, molecular biology, and epidemiology to FP in the green turtle, Chelonia
mydas. Long-term goals included the development of assays for FP and study of any
role of environmental co-factors in the disease. This report is a continuation of that
effort and the results reported here bring us closer to understanding the role of a
tumor-associated herpesvirus in marine turtle fibropapillomatosis.
This research has demonstrated that marine turtle herpesviruses can persist for
extended periods of time as infectious agents in the marine environment and that wild
green turtles in Florida are exposed to the LETD-associated herpesvirus. This is the
first description of LETV infection in free-ranging. marine turtles. In addition, data is
presented that supports the hypothesis that LETV and FPHV infections are
independent. These data reveal new levels of complexity that must be addressed
before reliable serodiagnostic assays for herpesvirus infections of chelonians can be
developed for widespread application. The results reported here also raise new
concerns about the potential impact of infections by new herpesviruses on populations
of wild marine turtles, an area which has previously been unexplored by turtle
biologists. (8 page document
Seroepidemiological studies of herpesvirus-associated diseases of marine turtles: Fibropapillomatosis and lung-eye-trachea disease
We have developed immunological tests that can identify marine turtles in Florida (green and loggerhead) that have been exposed
to the LETV herpesvirus. The seroepidemiological data collected provides critical evidence about the relationship between
infection with the FP-associated herpesvirus and the LETV herpesvirus. The data supports the hypothesis that LETV and FPHV
infections are independent infections of marine turtles. The data shows that wild green turtles in Florida are exposed to the
LETD-associated herpesvirus, which is the first description ofLETV infection in free-ranging marine turtles. To our knowledge,
the antigenic proteins identified in this study are not only the first proteins from a reptilian herpesvirus to be cloned and
expressed, but they represent the first reptilian herpesvirus proteins to be identified as immunogenic in their host species. (16 page document
Innovation processes and industrial districts
In this survey, we examine the operations of innovation processes within industrial districts by exploring the ways in which differentiation, specialization, and integration
affect the generation, diffusion, and use of new knowledge in such districts. We begin with an analysis of the importance of the division of labour and then investigate the effects of social embeddedness on innovation. We also consider the effect of forms of organization within industrial districts at various stages of product and process life, and we examine the negative aspects of embeddedness for innovation. We conclude with a discussion of the possible consequences of new information and
communications technologies on innovation in industrial districts
Promoting âNormalcyâ for Foster Children: The Preventing Sex Trafficking and Strengthening Families Act
This Article begins by analyzing the legal backdrop from which the Act emerged. It then discusses the promulgation and provisions of the Act. Lastly, this Note comments on the Act, specifically addressing its necessity, its likely effectiveness, and whether it adequately addresses the pressing concerns of foster youth in the United State
Graph Saturation in Multipartite Graphs
Let be a fixed graph and let be a family of graphs. A
subgraph of is -saturated if no member of
is a subgraph of , but for any edge in , some element of
is a subgraph of . We let and
denote the maximum and minimum size of an
-saturated subgraph of , respectively. If no element of
is a subgraph of , then .
In this paper, for and we determine
, where is the complete balanced -partite
graph with partite sets of size . We also give several families of
constructions of -saturated subgraphs of for . Our results
and constructions provide an informative contrast to recent results on the
edge-density version of from [A. Bondy, J. Shen, S.
Thomass\'e, and C. Thomassen, Density conditions for triangles in multipartite
graphs, Combinatorica 26 (2006), 121--131] and [F. Pfender, Complete subgraphs
in multipartite graphs, Combinatorica 32 (2012), no. 4, 483--495].Comment: 16 pages, 4 figure
Recommended from our members
Eels I: The Eel Passage Research Center: Lessons Learned Regarding Structure and Process for Effective Collaboration
Recommended from our members
Machine learning for automated sonar monitoring of outmigrating American eel behavior
Abundance of American eel (Anguilla rostrata) is low compared to historical levels, which makes it a species of management concern. Adult American eel are vulnerable to hydropower turbine mortality during outmigration from inland waters to their spawning ground in the Sargasso Sea. Morphological and behavioral characteristics of the species make it particularly challenging to provide safe downstream passage at hydropower projects. Furthermore, outmigration of adult eels is episodic and protracted, typically extending over a period of several months or more each year. Consequently, design, optimization, and operation of downstream passage facilities that are economical and biologically effective requires knowledge of eel behavior during their downstream migration. Site-specific information requirements include knowledge of when eels are approaching hydropower facilities; pathways of approach and passage; and near-field behavioral responses to facility structures including intakes, guidance structures, and bypasses.
The EPRI Eel Passage Research Center investigated three sonar technologies for observing the abundance and behavior of outmigrating adult eels. Among the three sonar types tested, ARIS multibeam imaging sonar holds the most promise for correctly identifying eels at up to 16-20 meters range. While multi-beam imaging sonar can provide the needed data, the protracted nature of adult eel outmigration and the rate of sonar data production make automated data analysis essential for cost-effective monitoring.
Our ongoing project has the goal of developing machine-based detection of American eel from ARIS sonar data. The project will: (1) extract training and validation data from ARIS sonar records collected at the Iroquois Water Control Dam on the St. Lawrence River, USA/Canada; (2) utilize two-dimensional wavelet transform analysis to filter noise and increase contrast of the sonar images; (3) apply convolutional neural network analysis to classify the images into three types of objects â background, eel, and moving, non-eel target; (4) quantify the performance of the analysis system
Denominator Bounds and Polynomial Solutions for Systems of q-Recurrences over K(t) for Constant K
We consider systems A_\ell(t) y(q^\ell t) + ... + A_0(t) y(t) = b(t) of
higher order q-recurrence equations with rational coefficients. We extend a
method for finding a bound on the maximal power of t in the denominator of
arbitrary rational solutions y(t) as well as a method for bounding the degree
of polynomial solutions from the scalar case to the systems case. The approach
is direct and does not rely on uncoupling or reduction to a first order system.
Unlike in the scalar case this usually requires an initial transformation of
the system.Comment: 8 page
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