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Cattle As Technological Interventions: The Gender Effects Of Water Demand In Dairy Production In Uganda, Elizabeth Ransom, Carmen Bain, Harleen Bal, Natasha Shannon Sep 2017

Cattle As Technological Interventions: The Gender Effects Of Water Demand In Dairy Production In Uganda, Elizabeth Ransom, Carmen Bain, Harleen Bal, Natasha Shannon

Sociology and Anthropology Faculty Publications

Smallholder dairy production dominates the country of Uganda, with over 90% of the national herd owned by smallholders. To reduce hunger, malnutrition, and raise families out of poverty agricultural development, interventions in Uganda have focused on increasing milk production through the introduction of improved dairy cow breeds. Development actors, such as the East Africa Dairy Development (EADD) program in Uganda, see crossbreed dairy cows as a key technological intervention for improving production. Drawing on a multi-method study (spatial analysis, surveys, and qualitative interviews) of dairy smallholders, our paper examines the gendered effects of the introduction of crossbreed dairy cows. To …


Current Status Of American Bullfrog, Lithobates Catesbeianus, Invasion In Uruguay And Exploration Of Chytrid Infection, Gabriel Laufer, Noelia Gobel, Claudio Borteiro, Alvaro Soutullo, Claudio Martinez-Debat, Rafael O. De Sá Aug 2017

Current Status Of American Bullfrog, Lithobates Catesbeianus, Invasion In Uruguay And Exploration Of Chytrid Infection, Gabriel Laufer, Noelia Gobel, Claudio Borteiro, Alvaro Soutullo, Claudio Martinez-Debat, Rafael O. De Sá

Biology Faculty Publications

The American bullfrog Lithobates catesbeianus is an invasive species that can strongly affect native amphibian communities through competition, predation, or introduction of diseases. This frog has invaded multiple areas in South America, for which niche models predict suitable environments across much of the continent. This paper reveals the state of the invasion of this species in Uruguay and its possible relationship with the chytrid pathogenic fungus, Batrachochytrium dendrobatidis. Surveys at invaded sites were conducted from 2007 to 2015, identified two populations undergoing recent range expansion (one of them exponential), two populations that failed to establish, and a new record …


Agricultural Intensification Can Preserve The Brazilian Cerrado: Applying Lessons From Mato Grosso And Goia's To Brazil’S Last Agricultural Frontier, Stephanie A. Spera Aug 2017

Agricultural Intensification Can Preserve The Brazilian Cerrado: Applying Lessons From Mato Grosso And Goia's To Brazil’S Last Agricultural Frontier, Stephanie A. Spera

Geography and the Environment Faculty Publications

Food security and climate change are two pressing issues shaping the future of tropical land use. Brazil, home to abundant land that is rich in carbon, water, and biodiversity and often cleared for agropastoral and renewable energy purposes, is the ideal location for studying socioeconomic and environmental trade-offs of land use dynamics. Here, I use recent (2000–2016) land-use land-cover change dynamics in the established agricultural states of Mato Grosso and Goia's to demonstrate how incentivizing intensive agricultural practices and improving degraded pastures may be a means by which Brazil can increase agricultural production while conserving the remainder of the Cerrado. …


Chondrocranium And Internal Oral Morphology Of The Tadpole Of Corythomantis Greeningi (Anura: Hylidae), Marianna Isabella Rosa Rodrigues De Oliveira, Luiz Norberto Weber, Rafael O. De Sá, Johnny Sousa Ferreira, Anna Evelin Coimbra Libório, André Masahide Guimarães Takazone Jul 2017

Chondrocranium And Internal Oral Morphology Of The Tadpole Of Corythomantis Greeningi (Anura: Hylidae), Marianna Isabella Rosa Rodrigues De Oliveira, Luiz Norberto Weber, Rafael O. De Sá, Johnny Sousa Ferreira, Anna Evelin Coimbra Libório, André Masahide Guimarães Takazone

Biology Faculty Publications

Corythomantis greeningi is a casque-headed frog that occurs in xeric and sub-humid regions of northeastern Brazil. Individuals are often found on rocks on banks of temporary streams or in ponds upon “lajedos”. Suctorial tadpoles are often found clasping to the rocks in the streams so as not to be dragged by the current; therefore, they have modified external and internal morphology. Here, we describe the internal oral anatomy and the chondrocranium of the tadpole of C. greeningi and compare it to the available descriptions of Lophyohylinae and other suctorial tadpoles. The internal oral morphology in C. greeningi resembles pond-dwelling casque-headed …


A Global Community Effort To Decipher The Unique Biology Of Annual Killifish, Nibia Berois, Graciela Garcia, Rafael O. De Sá Jun 2017

A Global Community Effort To Decipher The Unique Biology Of Annual Killifish, Nibia Berois, Graciela Garcia, Rafael O. De Sá

Biology Faculty Publications

Over the past 50 years, annual killifishes arose as alternative model organisms for studies of vertebrate biology. The annual fish offers exceptional advantages for studies of genetics, genomics, developmental biology, population dynamics, ecology, biogeography, and evolution. They inhabit extremely variable freshwater environments in Africa and South America, have a short lifespan and a set of unique and fascinating developmental characteristics. Embryos survive within the dry substrate during the dry season, whereas the adult population dies. Thus, the survival of the populations is entirely dependent on the buried embryos that hatch the next rainy season. Although Old and New World species …


Assessment Of The Calling Detection Probability Throughout The Day Of Two Invasive Populations Of Bullfrog (Lithobates Catesbeianus) In Uruguay, Gabriel Laufer, Noelia Gobel, Alvaro Soutullo, Claudio Martinez-Debat, Rafael O. De Sá May 2017

Assessment Of The Calling Detection Probability Throughout The Day Of Two Invasive Populations Of Bullfrog (Lithobates Catesbeianus) In Uruguay, Gabriel Laufer, Noelia Gobel, Alvaro Soutullo, Claudio Martinez-Debat, Rafael O. De Sá

Biology Faculty Publications

Bullfrog invasion is a major conservation concern in South America, so there is an urgent need to detect and monitor its many invasion foci. Amphibian sampling methods commonly use calling display, specifically the nuptial calls of males. With the aim of obtaining the better day period to sample and monitor Lithobates catesbeianus presence, we recorded its calls at three ponds in two invaded localities in Uruguay (Aceguá, Cerro Largo, and San Carlos, Maldonado) during the reproductive season. Then, we studied the records, obtaining a subsample of calling intensity at the first 5 minutes for each hour. We detected that vocalization …


Precipitation Drivers Of Cropping Frequency In The Brazilian Cerrado: Evidence And Implications For Decision-Making, Keith R. Spangler, Amanda H. Lynch, Stephanie A. Spera Apr 2017

Precipitation Drivers Of Cropping Frequency In The Brazilian Cerrado: Evidence And Implications For Decision-Making, Keith R. Spangler, Amanda H. Lynch, Stephanie A. Spera

Geography and the Environment Faculty Publications

The Amazon basin has been subjected to unprecedented rates of land-use change over the past several decades, primarily as a result of the expansion of agriculture. Enhanced rain forest conservation efforts toward the end of the twentieth century slowed deforestation of the Amazon but, in turn, increased demand for land repurposing in the adjacent Cerrado (savanna) region, where conservation regulations are less strict. To maintain or increase yields while minimizing the need for additional land, agricultural producers adopted a form of intensification in which two rain-fed crops are planted within a single growing season (double cropping). Using 10 years (August …


Black Bugbane & The Blues: Interactions Between Our Wildflower Of The Year And The Insect World, W. John Hayden Apr 2017

Black Bugbane & The Blues: Interactions Between Our Wildflower Of The Year And The Insect World, W. John Hayden

Biology Faculty Publications

No, this article has nothing to do with American Roots music. Black Bugbane is one of several common names for the 2017 VNPS Wildflower of the Year, Actaea racemosa. And Blues refers to a subfamily of lycaenid butterflies, commonly referred to as Blues or Azures. The interactions between Black Bugbane, a.k.a., Black Cohosh, Appalachian Azure butterflies (Celastrina neglectamajor), and ants was recently summarized by VNPS charter member and past president Nicky Staunton (2015). In brief, Black Bugbane is the sole food source for caterpillars of Appalachian Azure butterflies, a situation that, superficially, might seem like any other caterpillar and host …


Molecular And Morphological Data Reveal Three New Cryptic Species Of Chiasmocleis (Mehely 1904) (Anura, Microhylidae) Endemic To The Atlantic Forest, Brazil, Mauricio C. Forlani, João F. R. Tonini, Carlos A. G. Cruz, Hussam Zaher, Rafael O. De Sá Feb 2017

Molecular And Morphological Data Reveal Three New Cryptic Species Of Chiasmocleis (Mehely 1904) (Anura, Microhylidae) Endemic To The Atlantic Forest, Brazil, Mauricio C. Forlani, João F. R. Tonini, Carlos A. G. Cruz, Hussam Zaher, Rafael O. De Sá

Biology Faculty Publications

Three new cryptic species of Chiasmocleis from the Atlantic Forest of Brazil are described. Two of these species occur in the northeastern states of Sergipe and Bahia, whereas the third species is found in the southeastern state of São Paulo. The new species can be distinguished from other congeneric species by the molecular data, as evidenced in the phylogeny, and by a combination of morphological characters including: size, foot webbing, dermal spines, and coloration patterns. Chiasmocleis species differ in osteological traits, therefore we also provide an osteological description of each new species and comparisons with data reported for other species …


The Relationship Between Tropical Cyclone Activity, Nutrient Loading, And Algal Blooms Over The Great Barrier Reef, Chelsea L. Parker, Amanda H. Lynch, Stephanie A. Spera, Keith R. Spangler Feb 2017

The Relationship Between Tropical Cyclone Activity, Nutrient Loading, And Algal Blooms Over The Great Barrier Reef, Chelsea L. Parker, Amanda H. Lynch, Stephanie A. Spera, Keith R. Spangler

Geography and the Environment Faculty Publications

The Great Barrier Reef, the world’s largest coral reef ecosystem, is subject to many environmental stressors. This study utilizes remotely sensed Moderate Resolution Imaging Spectroradiometer (MODIS) chlorophyll a concentration data to explore statistically significant relationships between local-scale tropical cyclone disturbance and relative water quality between 2004–2014. The study reveals that tropical cyclone activity reduces water quality at 8- and 16-day time lags. Relationships suggest that at early stages (during and just after cyclone activity) algal response is induced primarily through wind-driven sediment re-suspension. However, wind speed in isolation only increases minimum levels of chlorophyll a, rather than mean or …


Livestock-Livelihood Linkages In Uganda: The Benefits For Women And Rural Households?, Elizabeth Ransom, Carmen Bain, Iim Halimatusa'diyah Jan 2017

Livestock-Livelihood Linkages In Uganda: The Benefits For Women And Rural Households?, Elizabeth Ransom, Carmen Bain, Iim Halimatusa'diyah

Sociology and Anthropology Faculty Publications

Livestock are an important component of rural households and gendered livelihood practices throughout sub-Saharan Africa. Widespread within the development literature is the belief in the livestock ladder, with poorer households often owning small stock and wealthier households owning large stock, with the assumption that poor households can utilize livestock to build their asset base and overtime this would allow poorer households to expand from small stock to large stock, in so doing climb the livestock ladder. There is also an assumption in the literature that women are more likely to oversee small stock. In addition, some well-known agricultural development programs …


The Progression Of Lyme Disease In The State Of Virginia, Margaret Michel Jan 2017

The Progression Of Lyme Disease In The State Of Virginia, Margaret Michel

Honors Theses

Lyme disease has spread in the United States from the northeast to more southern and western parts of the country. It has been shown that the tick which most often carries the Lyme disease pathogen (Borrelia burgdorferi) in North America, Ixodes scapularis, has also spread to these new areas of concern. In Virginia, the disease has progressed from the eastern shore to the western, more mountainous regions. Through obtaining historical museum specimens of mice from 11 locations in Virginia, we seek to determine whether the Lyme disease causing pathogen, B. burgdorferi, has always been present in …


Investigating Medicinally Important Portein-Protein And Protein-Ligand Interactions : A Computational Approach, Cooper Ashley Taylor Jan 2017

Investigating Medicinally Important Portein-Protein And Protein-Ligand Interactions : A Computational Approach, Cooper Ashley Taylor

Honors Theses

Molecular dynamics (MD) simulations and computational chemistry allow for an atomistic understanding of protein-protein and protein-ligand binding motifs. Through the use of MD, medicinally relevant complexes can be examined in detail unattainable by experimental methods. Within this work, systems pertinent to both Alzheimer’s Disease and HIV-1 are probed and thoroughly sampled to help elucidate potential therapeutic pathways. We used molecular dynamics and free energy estimations to gauge the affinity for the binary and ternary complexes of KLC1, APP and JIP1, three proteins all believed to be involved in the propagation of Alzheimer’s Disease. Two areas of thought exist suggesting that …


Sepals And Petals And Stamens—Oh, My! Or, A Brief Discourse On Putative Homologies Of Perianth Elements Of Common Black Cohosh, W. John Hayden Jan 2017

Sepals And Petals And Stamens—Oh, My! Or, A Brief Discourse On Putative Homologies Of Perianth Elements Of Common Black Cohosh, W. John Hayden

Biology Faculty Publications

I encountered some contradictory information while preparing to write the 2017 Wildflower of the Year brochure: some sources describe flowers of Actaea racemosa, Common Black Cohosh, as having petals, while others say petals are absent. How can that be? How could there be such uncertainty about this common plant, one known to science since before the time of Linnaeus? After a little research, I decided to describe Black Cohosh flowers as having a series of organs interpretable either as staminodes (nonfunctional stamens) or as petals located between its sepals and stamens (Figure 1). Frankly, I waffled on the petal issue, …


Actaea Racemosa: The Slender Wands Of Flowering Common Black Cohosh Beckon Us To Explore Woodlands, W. John Hayden Jan 2017

Actaea Racemosa: The Slender Wands Of Flowering Common Black Cohosh Beckon Us To Explore Woodlands, W. John Hayden

Biology Faculty Publications

Common Black Cohosh is a perennial rhizomatous forest herb. Its horizontal rhizomes bear numerous adventitious roots on the underside and aerial stems of annual duration on the upper side, along with knobby scars left from aerial stems of previous years. Leaves are alternate, twice or thrice compound in ternate or pinnate patterns, and large—up to 1 m long. Individual leaflet size and shape vary with position in the large compound leaves, with position of a leaf on the stem, and from population to population. Most often leaflets are coarsely serrate, lobed to deeply incised, with a truncate to cuneate base …


Identification Of Rifampicin Resistance Mutations In Escherichia Coli, Including An Unusual Deletion Mutation, Eugene Y. Wu, Angela K. Hilliker Jan 2017

Identification Of Rifampicin Resistance Mutations In Escherichia Coli, Including An Unusual Deletion Mutation, Eugene Y. Wu, Angela K. Hilliker

Biology Faculty Publications

Rifampicin is an effective antibiotic against mycobacterial and other bacterial infections, but resistance readily emerges in laboratory and clinical settings. We screened Escherichia coli for rifampicin resistance and identified numerous mutations to the gene encoding the β chain of RNA polymerase (rpoB), including an unusual nine nucleotide deletion mutation. Structural modeling of the deletion mutant indicates locations of potential steric clashes with rifampicin. Sequence conservation in the region near the deletion mutation suggests a similar mutation may also confer resistance during the treatment of tuberculosis.


On The Complexity Of Simples, Pharmacognosy, And Actaea Racemosa, W. John Hayden Jan 2017

On The Complexity Of Simples, Pharmacognosy, And Actaea Racemosa, W. John Hayden

Biology Faculty Publications

Pharmacognosy, a discipline at the intersection of botany and medicine, deals with knowledge about medicines derived from plants (Youngken 1950). A central goal of pharmacognosy is the accurate and consistent taxonomic identification of medicinal plants and medicinal plant products. Unlike drugstore pill bottles, medicinal plants in nature do not come with labels. One aspect of pharmacognosy, then, is the identification of whole plants found in nature. Much as in field botany and plant systematics, this aspect of pharmacognosy involves learning to recognize species by overall appearance (gestalt), or by dichotomous keys, or both.


The Hidden History Of Humming Frogs, Rafael O. De Sá Jan 2017

The Hidden History Of Humming Frogs, Rafael O. De Sá

Biology Faculty Publications

In the depths of Brazil’s Atlantic Forest, researchers are battling to identify species before they are lost for good. Dr Rafael O de Sá, Professor of Biology at the University of Richmond, Virginia, USA, specialises in a group known as the ‘narrow-mouthed frogs’ and has already found four species new to science.