Blackburn D.G.,Trinity College at Hartford
Journal of Morphology | Year: 2015
Phylogenetic analyses indicate that viviparity (live-bearing reproduction) has originated independently in more than 150 vertebrate lineages, including a minimum of 115 clades of extant squamate reptiles. Other evolutionary origins of viviparity include 13 origins among bony fishes, nine among chondrichthyans, eight in amphibians, one in Paleozoic placoderms, six among extinct reptiles, and one in mammals. The origins of viviparity range geologically from the mid-Paleozoic through the Mesozoic to the Pleistocene. Substantial matrotrophy (maternal provision of nutrients to embryos during pregnancy) has arisen at least 33 times in these viviparous clades, with most (26) of these origins having occurred among fishes and amphibians. Convergent evolution in patterns of matrotrophy is widespread, as reflected by multiple independent origins of placentotrophy, histotrophy, oophagy, and embryophagy. Specializations for nutrient transfer to embryos are discontinuously distributed, reflecting the roles of phylogenetic inertia, exaptation (preadaptation), and constraint. Ancestral features that function in gas exchange and nutrition repeatedly and convergently have been co-opted for nutrient transfer, often through minor modification of their components and changes in the timing of their expression (heterochrony). Studies on functional and evolutionary morphology continue to play a central role in our attempts to understand viviparity and mechanisms of fetal nutrition. © 2014 Wiley Periodicals, Inc.
Agency: NSF | Branch: Standard Grant | Program: | Phase: Campus Cyberinfrastrc (CC-NIE) | Award Amount: 340.66K | Year: 2016
Trinity Colleges Next Generation Science Network and DMZ project dramatically increases institutional interconnectivity and cyberinfrastructure capability to facilitate data-intensive research and teaching opportunities. The Science DMZ gives researchers and teachers an unfettered direct path to Virtual Research Networks, Connecticut Education Network resources, and Internet2, bypassing legacy control mechanisms and thus allowing for higher speed interconnectivity. The resource brings the level of connectivity typically found at a large research university into the unique environment of a small liberal arts college.
The network upgrade replaces outdated campus wiring and networking hardware with that capable of 1Gbps for end node connectivity and multiple 10Gbps interconnects to science servers and the Connecticut Education Network (CEN). This is accomplished with the installation of new routers and switches in the Trinity College (Hartford, CT) campus science complex buildings, as well as upgrades to cyber-border equipment connecting to the Connecticut Education Network (CEN), an Internet2 partner. The project includes installation of performance-oriented monitoring software (PerfSonar) and will give researchers direct access to IPv6 resources.
Agency: NSF | Branch: Standard Grant | Program: | Phase: | Award Amount: 316.67K | Year: 2011
The Notch signaling system is a cell-to-cell communication mechanism that is found in virtually all multicellular organisms and allows developing cells to acquire their specialized cellular types (neuronal, muscular, digestive, reproductive, etc.). This system has many components, two of which are the main focus of this proposal. These are the Notch signal receptor molecule and the Serrate ligand that is capable of interacting with and affecting Notch receptor activity. The Serrate ligand can activate the receptor when these molecules are expressed on adjacent cells leading to the formation of different cell types. Serrate can also inhibit the receptor when these molecules are co-expressed on the same cell, preventing such cells from receiving a Notch signal and forming distinctive cellular types. This proposal investigates the specific regions and properties of the Serrate ligand that are responsible for inhibiting the Notch receptor hence investigating a crucial mechanistic aspect for controlling cellular specialization. The work utilizes targeted molecular-genetic mutation of the Serrate molecule with subsequent expression of these mutated forms in the fruit fly to investigate their effects on Notch signaling. The outcomes are expected to fully define and characterize the regions of Serrate that confer the inhibitory property of the ligand onto the Notch receptor and potentially define regions essential for Notch activation. The evolutionarily conserved nature of Notch system components allows for very broad applicability of the findings of this study to the homologous molecules in vertebrates. Further, this study will extend the understanding of cellular differentiation control in multicellular animals including stem cell differentiation mechanisms. The study will be conducted by undergraduate researchers providing these students with a strong background in molecular and genetic tools for subsequent professional training and development.
Agency: NSF | Branch: Standard Grant | Program: | Phase: Computing Ed for 21st Century | Award Amount: 2.11M | Year: 2013
Trinity College, in partnership with the Hartford Public School System, the Connecticut Chapter of the Computer Science Teachers Association, and other Hartford area high schools, will train approximately 30 Connecticut high school teachers to teach Advanced Placement (AP) computing courses in Connecticut high schools that currently do not teach AP computer science. The course will be based on a mobile Computer Science Principles curriculum, Mobile CSP, which uses the new mobile computing language, App Inventor for Android, to provide a rigorous, programming-based introduction to computational thinking. The main research question addressed is whether the Mobile CSP curriculum is an effective way to teach CS Principles and whether it can serve as one model to help train teachers for the CS 10K project. The curriculum is project-based and takes a constructionist approach to learning computing -- i.e., students learn through constructing their own artifacts and mental models. Student projects will focus on building socially useful, place-based mobile apps using the App Inventor programming language. In this way, student learning will be associated closely with their interests and grounded in their schools, their homes, and their communities. The curriculum, which was developed and tested at Trinity College and the Greater Hartford Academy of Mathematics and Science (GHAMAS) as one of the Phase 2 pilot courses for the College Boards CS Principles project, will be carefully evaluated along several dimensions, including its efficacy at improving programming and problem solving skills and its impact on student and teacher attitudes toward computer science education. The Mobile CSP project has three main goals: (i) To develop a rigorous computer science principles AP curriculum based on mobile computing; (ii) to teach it to Connecticut teachers in 6-week summer workshops; and (iii) to support participating teachers in their effort to implement the AP pilot courses in Connecticut schools that do not currently teach AP computer science. The 2013-2014 cohort of teachers will be drawn primarily from the Hartford school district, a district whose students come mostly from demographic and socio-economic backgrounds that have been underrepresented in computer science. In years two and three the project will expand to other, similarly situated, Connecticut cities and towns.
Agency: NSF | Branch: Standard Grant | Program: | Phase: | Award Amount: 95.64K | Year: 2012
This project introduces undergraduate students to computational thinking (CT) by engaging them to create apps for mobile phones and tablets that are both useful and personally meaningful. CT is a 21st century STEM literacy whose concepts are needed by informed citizens and workers to solve problems and understand complex systems in many domains.
In this project, students learn CT by creating mobile apps using App Inventor, a visual blocks-based programming environment. The project is developing online curricular modules that use mobile app programming to teach CT principles and mobile computing design concepts. These modules include web-based tutorials, video lectures, screencasts, programming exercises, and quizzes --- online materials that give students more in-class time to engage in active learning. Several introductory and intermediate courses are being developed based on these modules. The project is also devising, testing, and evaluating new techniques for assessing students CT knowledge in the context of mobile computing and project-based courses.
In partnership with MITs new Center for Mobile Learning, this project is widely disseminating curricular materials, course designs, and assessment rubrics, and is building a national community of undergraduate educators focused on teaching CT via mobile computing.
This project reflects mobile computings transformation of society by building a curriculum in which undergraduates learn CT not by merely using apps, but by creating them. The materials developed in this project will support both novice and intermediate students in constructionist learning and in design, innovation, and entrepreneurship activities that connect computer science to other disciplines.
Agency: NSF | Branch: Standard Grant | Program: | Phase: ANIMAL DEVELOPMENTAL MECHANSMS | Award Amount: 488.88K | Year: 2013
A central question in biology is how complex forms have evolved. One common way for animals to become complex is through being built of repeated parts, like body segments, that can be changed independently. The largest group of segmented animals is the arthropods. Most arthropods make their segments by adding them from a posterior region called the growth zone. A common set of genes has recently been hypothesized to control the growth zone in diverse arthropods. However, the cell processes that elongate the growth zone are elusive. Without understanding the cell processes that normally elongate the growth zone, it is impossible to explain the role of genes in controlling segmentation. This work will synthesize two approaches to understanding growth zone elongation and segmentation. First, direct measures of cell processes such as cell division, cell shape, cell motility and gene function will be made in three arthropod species, a crustacean and two insects. Then, these data will be fed into computational models of segment formation. Lab results will keep the computer models realistic while computer models will allow rapid exploration of relationships between genes and cell processes and thus inform new lab work. This project will be the first to bring computational modeling to a fine-grain analysis of arthropod sequential segmentation. The results will be important for studies of development and for synthetic biology. The proposed work is an international collaboration between 3 research labs with both unique and overlapping expertise. Undergraduates, graduate students, and post-docs will participate in multi-disciplinary training that synthesizes laboratory and computational approaches, fostering an integration of quantitative and experimental skills early in their careers. Importantly, students will also have the opportunity for international exchange between Israeli and US labs, through summer exchanges between the labs, and live exchange of ideas during regular web-based meetings. The outcomes of this work will also be shared with the public through outreach events in K-12 classes, local science centers, museums and public lectures such as the popular Science Cafés.
Agency: NSF | Branch: Standard Grant | Program: | Phase: Cellular Dynamics and Function | Award Amount: 212.25K | Year: 2016
Cell-to-cell variation is an important property of cell populations that has implications for the understanding of embryonic development, the immune system, the sense of smell, and many other normal and abnormal processes. The role of cell-to-cell variability in these processes is currently not well understood, and in this project the activity of an important signaling protein will be measured in individual cells of a single-celled, but social, organism. This will provide, cell-by-cell, the resolution needed to understand in this system the significance of cell variability. Undergraduate students will have an opportunity to engage in interdisciplinary research involving biochemistry, microfluidics, computer simulations and the development of new analytical tools.
Cyclic AMP (cAMP) is a signal (acting through Protein Kinase B, PKB) that induces cell aggregation and the onset of the social phase of the life cycle of the amoeba, Dictyostelium discoideum. Microfluidic single-cell assays of PKB will be carried out on single cells of Dictyostelium, enabling quantitative measurement of variability and a greater understanding of the significance of this variability as the organism responds to signaling with cAMP.
Agency: NSF | Branch: Standard Grant | Program: | Phase: ATMOSPHERIC CHEMISTRY | Award Amount: 106.50K | Year: 2016
The MRI instrumentation seeks to engage neighborhoods and schools in an urban setting (Washington DC) to broaden the participation of underrepresented groups and low-income students in understanding environmental issues that affect their quality of life, health and environmental justice. A combination of research and educational tasks will advance both the understanding of urban environmental factors and inquiry based STEM education. Partnerships will be sought in neighborhoods where residents are concerned about their ambient air quality, with students informing them specifically for volatile organic compounds (VOCs), many of which are known toxins. Characterizing spatial and temporal variations of atmospheric VOCs will complement prior studies of particulate matter and metals, help inform studies of health disparities, and allow direct comparisons with other urban areas.
The central instrument is a gas chromatograph / mass spectrometer (GCMS) to be housed in a new science building at Trinity Washington University, a Minority Serving Institution in Washington, D.C. with a traditional liberal arts college curriculum for women. Encouragement of underepresented minorities to actively participate in STEM fields serves, demographically, the national interst.
Trinity Washington University is a non-Ph.D. granting institution as defined in Section IV of the NSF MRI solicitation
Agency: NSF | Branch: Standard Grant | Program: | Phase: ANALYSIS PROGRAM | Award Amount: 105.77K | Year: 2014
The goal of this project is to further the research of the principal investigator (PI) in harmonic analysis, a branch of mathematics that is an area of active research and also one that is very important for its applications to a wide variety of problems in physics and engineering. The research will be conducted a Trinity College, a liberal arts college that focuses on undergraduate education but requires its faculty to maintain active research programs. This project will further the development of mathematical research at Trinity. Undergraduate students will be given the opportunity to participate in the project. This will help Trinity expand its undergraduate research programs to include mathematics. Undergraduate research enhances the quality of undergraduate education and better prepares students for advanced work in science, mathematics, and engineering. In particular, the PI (himself a Mexican-American) hopes to recruit women and members of underrepresented minority groups to participate in the research project, thereby increasing diversity in mathematics and the sciences.
In this project the PI will study weighted norm inequalities in harmonic analysis. The goal is to further the recent work of the PI in three closely related areas: Rubio de Francia extrapolation, sharp constant estimates, and two-weight norm inequalities. Recent work by a number of mathematicians, including the PI, on sharp constant estimates with Muckenhoupt weights and extrapolation theory has yielded new results and a number of techniques that should be applicable to additional problems, including endpoint estimates for functions of bounded mean oscillation and extrapolation estimates for matrix weights. These results in turn will yield applications to regularity estimates for degenerate partial differential equations and to the study of variable Lebesgue spaces. The PI will also work on two-weight estimates, particularly on the separated bump conjecture for singular integrals and Riesz potentials.
Agency: NSF | Branch: Standard Grant | Program: | Phase: | Award Amount: 234.96K | Year: 2015
With this award, the Chemical Structure, Dynamics & Mechanisms B Program of the Division of Chemistry is fudning Professor Timothy Curran of the Department of Chemistry at Trinity College to develop model systems for exploring the physical and chemical properties of beta-sheets, a common protein secondary structure wherein two protein chains are aligned parallel to each other. Formation of beta-sheets has been implicated in amyloid diseases such as Alzheimers disease. Although there are existing model systems for beta-sheets, their use has been limited because these model systems aggregate and become insoluble, making them difficult to study. Professor Curran and his students have discovered a rigid, cyclic molecule that incorporates the metals, iron and tungsten, and they have discovered ways to append two short protein chains to this cyclic molecule. These protein chains are aligned parallel to each other. The goal of this research is to determine whether the two protein chains linked to the rigid cyclic molecule will form beta-sheets, and whether changes to the iron and tungsten atoms can prevent the problem of aggregation. If successful this work will enable other researchers to better understand the forces that drive beta-sheet formation. The project lies at the interface of organic, inorganic and biochemistry, and is therefore well suited to the education of undergraduate science students. Undergraduate co-workers, including those from groups underrepresented in sciences, and some high school students will take part in this funded project.
Tungsten bis(alkyne)complexes are ununsual in that they are air stable. In general, the alkyne ligands rotate around the tungsten center; this is true for both acyclic and cyclic complexes. In recent work, a cyclic tungsten bis(alkyne) complex derived from a dialkynyl 1,1-disubstitutedferrocene has been discovered and found to rather rigidly juxtapose the two alkyne ligands in solution. The rigid nature of this ring system and its ability to hold the two alkynes in close proximity will be used to explore whether peptides appended to the two alkynes will develop cross-strand hydrogen bonds and adopt beta-sheet conformations. Peptides will be appended to the alkynes via amide bonds made to either methyleneamine or methylenecarboxyl linkers. If these peptide derivatives do adopt beta-sheet conformations, then their ability to aggregate will be assessed. If aggregation is observed, oxidation of the iron atom in the ferrocene moiety will be examined to determine whether charge-charge repulsion can disrupt aggregation. The long-term goal of this work is to develop a model system for studying beta-sheets and the factors that contribute to their aggregation.