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Full-Text Articles in Biology

Natural Variation In Gestational Cortisol Is Associated With Patterns Of Growth In Marmoset Monkeys (Callithrix Geoffroyi), Aaryn C. Mustoe, Andrew K. Birnie, Andrew V. Korgan, Jonathan Bruce Santo, Jeffrey French Dec 2011

Natural Variation In Gestational Cortisol Is Associated With Patterns Of Growth In Marmoset Monkeys (Callithrix Geoffroyi), Aaryn C. Mustoe, Andrew K. Birnie, Andrew V. Korgan, Jonathan Bruce Santo, Jeffrey French

Psychology Faculty Publications

High levels of prenatal cortisol have been previously reported to retard fetal growth. Although cortisol plays a pivotal role in prenatal maturation, heightened exposure to cortisol can result in lower body weights at birth, which have been shown to be associated with adult diseases like hypertension and cardiovascular disease. This study examines the relationship between natural variation in gestational cortisol and fetal and postnatal growth in marmoset monkeys. Urinary samples obtained during the mother’s gestation were analyzed for cortisol. Marmoset body mass index (BMI) was measured from birth through 540 days in 30- or 60-day intervals. Multi-level modeling was used …


Molecular Systematics Of The Middle American Genus Hypopachus (Anura: Microhylidae), Eli Greenbaum, Eric N. Smith, Rafael O. De Sá Nov 2011

Molecular Systematics Of The Middle American Genus Hypopachus (Anura: Microhylidae), Eli Greenbaum, Eric N. Smith, Rafael O. De Sá

Biology Faculty Publications

We present the first phylogenetic study on the widespread Middle American microhylid frog genus Hypopachus. Partial sequences of mitochondrial (12S and 16S ribosomal RNA) and nuclear (rhodopsin) genes (1275 bp total) were analyzed from 43 samples of Hypopachus, three currently recognized species of Gastrophryne, and seven arthroleptid, brevicipitid and microhylid outgroup taxa. Maximum parsimony (PAUP), maximum likelihood (RAxML) and Bayesian inference (MrBayes) optimality criteria were used for phylogenetic analyses, and BEAST was used to estimate divergence dates of major clades. Population-level analyses were conducted with the programs NETWORK and Arlequin. Results confirm the placement of Hypopachus …


Analysis Of Migration Models Of Biogeography-Based Optimization Using Markov Theory, Haiping Ma, Daniel J. Simon Sep 2011

Analysis Of Migration Models Of Biogeography-Based Optimization Using Markov Theory, Haiping Ma, Daniel J. Simon

Electrical and Computer Engineering Faculty Publications

Biogeography-based optimization (BBO) is a new evolutionary algorithm inspired by biogeography, which involves the study of the migration of biological species between habitats. Previous work has shown that various migration models of BBO result in significant changes in performance. Sinusoidal migration models have been shown to provide the best performance so far. Motivated by biogeography theory and previous results, in this paper a generalized sinusoidal migration model curve is proposed. A previously derived BBO Markov model is used to analyze the effect of migration models on optimization performance, and new theoretical results which are confirmed with simulation results are obtained. …


Prescribed Fire Effects On The Summer And Fall Herbs Of Mesic Deciduous Forests, Margaret Wilder May 2011

Prescribed Fire Effects On The Summer And Fall Herbs Of Mesic Deciduous Forests, Margaret Wilder

Mahurin Honors College Capstone Experience/Thesis Projects

After years of fire suppression, high intensity forest fires were destructive to surrounding areas. Historically, fire was common in the eastern United States, but was suppressed over the past century, and recently has become a major tool in forest management. But to date, there have been no studies on the influence of fire on mesic sites in the eastern United States. Because fire is being reintroduced as a management practice, it is critical to know the influence of fire in this region. This study seeks to understand the influences of fire on summer and fall herbs in the western mesophytic …


Developing Mechanisms For The Transfer And/Or Adjustment Of Rock Lobster Shares Between Sectors In Western Australia And South Australia, Department Of Fisheries May 2011

Developing Mechanisms For The Transfer And/Or Adjustment Of Rock Lobster Shares Between Sectors In Western Australia And South Australia, Department Of Fisheries

Fisheries management papers

No abstract provided.


Love: A Biological, Psychological And Philosophical Study, Heather M. Chapman May 2011

Love: A Biological, Psychological And Philosophical Study, Heather M. Chapman

Senior Honors Projects

The concept of love has been an eternally elusive subject. It is a definition and meaning that philosophers, psychologists, and biologists have been seeking since the beginning of time. Wars have been waged and fought over it, while friendships have been initiated and have ended because of this idea. But what exactly is love, and why is it important to define this enigma?

In order to help define this idea of love, several books and numerous research articles were consulted, and interviews were conducted with faculty of The University of Rhode Island. Dr. Nasser Zawia was interviewed, in order to …


The Transition From 3-D To 2-D Visual Stimuli And Its Effect On Paired-Associate Learning, Amanda Beers Apr 2011

The Transition From 3-D To 2-D Visual Stimuli And Its Effect On Paired-Associate Learning, Amanda Beers

Mahurin Honors College Capstone Experience/Thesis Projects

A single experiment investigated the influence of varying dimensions of visual stimuli on the ability of academically gifted adolescents to recall paired-associations. Fifty-two participants were randomly assigned to one of four groups. Each group was asked to memorize the same set of 15 paired-word associations. The first group was presented with words only. The second group was presented with words and 2- dimensional (2-D) representations of each word. The third group was presented with words along with 3-dimensional (3-D) representations of the words. The fourth group was also presented words along with 3-D objects; however, this group was instructed to …


An Exploration Of Pharmacognosy And Its Potential In The Multi-Faceted Solution Required To Address Hiv/Aids In Sub-Saharan Africa, Alexandra Sassi Apr 2011

An Exploration Of Pharmacognosy And Its Potential In The Multi-Faceted Solution Required To Address Hiv/Aids In Sub-Saharan Africa, Alexandra Sassi

Pell Scholars and Senior Theses

This work has both both biological and anthropoligcal foci. It addresses research done on the medicinal properties of plants and how this research could make positive contributions to the current social and biological issues surrounding the HIV/AIDS epidemic in sub-Saharan Africa.


Fracture In Teeth—A Diagnostic For Inferring Bite Force And Tooth Function, Paul J. Constantino, Brian R. Lawn, James J.-W. Lee, Peter W. Lucas Apr 2011

Fracture In Teeth—A Diagnostic For Inferring Bite Force And Tooth Function, Paul J. Constantino, Brian R. Lawn, James J.-W. Lee, Peter W. Lucas

Biological Sciences Faculty Research

Teeth are brittle and highly susceptible to cracking. We propose that observations of such cracking can be used as a diagnostic tool for predicting bite force and inferring tooth function in living and fossil mammals. Laboratory tests on model tooth structures and extracted human teeth in simulated biting identify the principal fracture modes in enamel. Examination of museum specimens reveals the presence of similar fractures in a wide range of vertebrates, suggesting that cracks extended during ingestion or mastication. The use of ‘fracture mechanics’ from materials engineering provides elegant relations for quantifying critical bite forces in terms of characteristic tooth …


Variation, Systematics, And Relationships Of The Leptodactylus Bolivianus Complex (Amphibia: Anura: Leptodactylidae), W. Ronald Heyer, Rafael O. De Sá Jan 2011

Variation, Systematics, And Relationships Of The Leptodactylus Bolivianus Complex (Amphibia: Anura: Leptodactylidae), W. Ronald Heyer, Rafael O. De Sá

Biology Faculty Publications

Heyer, W. Ronald, and Rafael O. de Sá. Variation, Systematics, and Relationships of the Leptodactylus bolivianus Complex (Amphibia: Anura: Leptodactylidae). Smithsonian Contributions to Zoology, number 635, viii + 58 pages, 21 figures, 20 tables, 2011.—The Leptodactylus bolivianuscomplex has been considered to consist of one or two species, L. bolivianus alone or L. bolivianus and L. insularum. Detailed morphological analyses were undertaken to evaluate variation in the complex, which ranges from Costa Rica through Panama, across northern South America in the river valleys draining to the Caribbean, and throughout much of the Amazon basin with southern limits in Bolivia. Members of …


Subaerial Freshwater Stromatolites In Deer Cave, Sarawak – A Unique Geobiological Cave Formation, Joyce Lundberg, Donald A. Mcfarlane Jan 2011

Subaerial Freshwater Stromatolites In Deer Cave, Sarawak – A Unique Geobiological Cave Formation, Joyce Lundberg, Donald A. Mcfarlane

WM Keck Science Faculty Papers

A suite of distinctive freshwater subaerial phosphatic stromatolites is developed close to the northeastern entrance of Deer Cave, Gunung Mulu National Park, Sarawak, Borneo, in conditions of very low light but ample supply of nutrients from guano. These stromatolites are not particulate; they are composed of alternating layers of more porous and more dense amorphous hydroxylapatite. This biomineralization occurs as moulds of coccoid (the majority) and filamentous (less abundant) cyanobacteria. Mineralization occurs at a pH of ~ 7.0 in the extracellular sheaths and in micro-domains of varying carbonate content in the surrounding mucus of the biofilm. The most recent surfaces …


Epoxi: Comet 103p/Hartley 2 Observations From A Worldwide Campaign ; Astrophysical Journal Letters, K. Meech, M. A'Hearn, J. Adams, P. Bacci, J. Bai, L. Barrera, M. Battelino, J. Bauer, E. Becklin, B. Bhatt, N. Biver, D. Bockelee-Morvan, D. Bodewits, H. Bohnhardt, J. Boissier, B. Bonev, W. Borghini, J. Brucato, E. Bryssinck, M. Buie, H. Canovas, D. Castellano, S. Charnley, W. Chen, P. Chiang, Y. Choi, D. Christian, Y. Chuang, Anita Cochran, P. Colom, M. Combi, I. Coulson, J. Crovisier, N. Russo, K. Dennerl, K. Dewahl, M. Disanti, M. Facchini, T. Farnham, Y. Fernandez, H. Floren, U. Frisk, T. Fujiyoshi, R. Furusho, T. Fuse, G. Galli, D. Garcia-Hernandez, A. Gersch, Z. Getu Jan 2011

Epoxi: Comet 103p/Hartley 2 Observations From A Worldwide Campaign ; Astrophysical Journal Letters, K. Meech, M. A'Hearn, J. Adams, P. Bacci, J. Bai, L. Barrera, M. Battelino, J. Bauer, E. Becklin, B. Bhatt, N. Biver, D. Bockelee-Morvan, D. Bodewits, H. Bohnhardt, J. Boissier, B. Bonev, W. Borghini, J. Brucato, E. Bryssinck, M. Buie, H. Canovas, D. Castellano, S. Charnley, W. Chen, P. Chiang, Y. Choi, D. Christian, Y. Chuang, Anita Cochran, P. Colom, M. Combi, I. Coulson, J. Crovisier, N. Russo, K. Dennerl, K. Dewahl, M. Disanti, M. Facchini, T. Farnham, Y. Fernandez, H. Floren, U. Frisk, T. Fujiyoshi, R. Furusho, T. Fuse, G. Galli, D. Garcia-Hernandez, A. Gersch, Z. Getu

Physics Faculty Works

Earth- and space-based observations provide synergistic information for space mission encounters by providing data over longer timescales, at different wavelengths and using techniques that are impossible with an in situ flyby. We report here such observations in support of the EPOXI spacecraft flyby of comet 103P/Hartley 2. The nucleus is small and dark, and exhibited a very rapidly changing rotation period. Prior to the onset of activity, the period was ~16.4 hr. Starting in 2010 August the period changed from 16.6 hr to near 19 hr in December. With respect to dust composition, most volatiles and carbon and nitrogen isotope …