85 research outputs found
Building KiMoSin : design requirements for kinetic interfaces in protein education
Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007.Includes bibliographical references (leaves 18-19).Design guidelines for tools to enhance protein education are developed and applied to a prototype tool. A literature search and personal experience suggest kinetic, tangible models fill the current gaps in protein education. Thirty-six personal interviews with biology instructors and students set a mandate for three design guidelines for appropriate kinetic, tangible tools. The guidelines - simplicity, accuracy, and intuition - form a simple mantra to guide protein education tool design. The guidelines are then used to develop the prototype of an educational model of kinesin, a simple and vital motor protein. Application of these guidelines should result in design that provides students an interactive medium to discover the world of proteins. The prototyped kinesin model, nicknamed KiMoSin, shows promise of fulfilling that goal.by Ashlie Brown.S.B
Religious similarity and relationship quality
This analysis tested social support and joint religious activities as mediators of the relationship between religious similarity and relationship quality, as theorized by the relational spirituality framework. Using a national sample of couples (N = 621) from the Portraits of American Life Study (PALS), support for mediation was found only for partners' perceptions of religious similarity. All other hypotheses were unsupported. A discussion of results, implications, and limitations are included.Includes bibliographical references (pages 46-52)
Method and Meaning: Selections from the Gettysburg College Collection
What is art historical study and how it should be carried out are fundamental questions the exhibition Method and Meaning: Selections from the Gettysburg College Collection intends to answer. This student-curated exhibition is an exciting academic endeavor of seven students of art history majors and minors in the Art History Methods course. The seven student curators are Shannon Callahan, Ashlie Cantele, Maura D’Amico, Xiyang Duan, Devin Garnick, Allison Gross and Emily Zbehlik. As part of the class assignment, this exhibition allows the students to explore various art history methods on individual case studies. The selection of the works in the exhibition reflects a wide array of student research interests including an example of 18th century Chinese jade chime stone, jade and bronze replicas of ancient Chinese bronze vessels, a piece of early 20th century Chinese porcelain, oil paintings by Pennsylvania Impressionist painter Fern Coppedge, prints by Salvador Dalà and by German artist Käthe Kollwitz, and an early 20th century wood block print by Japanese artist Kawase Hasui. [excerpt]https://cupola.gettysburg.edu/artcatalogs/1014/thumbnail.jp
Tetraazamacrocyclic derivatives and their metal complexes as antileishmanial leads
© 2019 A total of 44 bis-aryl-monocyclic polyamines, monoaryl-monocyclic polyamines and their transition metal complexes were prepared, chemically characterized, and screened in vitro against the Leishmania donovani promastigotes, axenic amastigotes and intracellular amastigotes in THP1 cells. The IC 50 and/or IC 90 values showed that 10 compounds were similarly active at about 2-fold less potent than known drug pentamidine against promastigotes. The most potent compound had an IC 50 of 2.82 µM (compared to 2.93 µM for pentamidine). Nine compounds were 1.1–13.6-fold more potent than pentamidine against axenic amastigotes, the most potent one being about 2-fold less potent than amphotericin B. Fourteen compounds were about 2–10 fold more potent than pentamidine, the most potent one is about 2-fold less potent than amphotericin B against intracellular amastigotes in THP1 cells. The 2 most promising compounds (FeL7Cl 2 and MnL7Cl 2 ), with strong activity against both promastigotes and amastigotes and no observable toxicity against the THP1 cells are the Fe 2+ - and Mn 2+ -complexes of a dibenzyl cyclen derivative. Only 2 of the 44 compounds showed observable cytotoxicity against THP1 cells. Tetraazamacrocyclic monocyclic polyamines represent a new class of antileishmanial lead structures that warrant follow up studies
Speed Dependence of Atomic Stick-Slip Friction in Optimally Matched Experiments and Molecular Dynamics Simulations
Evidence that dopamine acts via Kisspeptin to Hold GnRH pulse frequency in check in Anestrous Ewes
Recent work has implicated stimulatory kisspeptin neurons in the arcuate nucleus (ARC) as important
for seasonal changes in reproductive function in sheep, but earlier studies support a role for
inhibitory A15 dopaminergic (DA) neurons in the suppression of GnRH (and LH) pulse frequency
in the nonbreeding (anestrous) season. Because A15 neurons project to the ARC, we performed
three experiments to test the hypothesis that A15 neurons act via ARC kisspeptin neurons to inhibit
LH in anestrus: 1) we used dual immunocytochemistry to determine whether these ARC neurons
contain D2 dopamine receptor (D2-R), the receptor responsible for inhibition of LH in anestrus; 2)
wetested the ability of local administration of sulpiride, a D2-R antagonist, into theARCto increase
LH secretion in anestrus; and 3) we determined whether an antagonist to the kisspeptin receptor
could block the increase in LH secretion induced by sulpiride in anestrus. In experiment 1, 40% of
this ARC neuronal subpopulation contained D2-R in breeding season ewes, but this increased to
approximately 80% in anestrus. In experiment 2, local microinjection of the two highest doses (10
and 50 nmol) of sulpiride into the ARC significantly increased LH pulse frequency to levels 3 times
that seen with vehicle injections. Finally, intracerebroventricular infusion of a kisspeptin receptor
antagonist completely blocked the increase in LH pulse frequency induced by systemic administration
of sulpiride to anestrous ewes. These results support the hypothesis that DA acts to inhibit
GnRH (and LH) secretion in anestrus by suppressing the activity of ARC kisspeptin neurons.We thank Heather Bungard and Jennifer Lydon (West Virginia
University Food Animal Research Facility) for the care of animals
and Paul Harton for his technical assistance in sectioning
tissue. We also thank Dr. Al Parlow and the National Hormone
and Peptide Program (Torrance, CA) for the reagents used to
measure LH and prolactin.http://endo.endojournals.org/am201
Post-diagnosis hemoglobin change associates with overall survival of multiple malignancies – results from a 14-year hospital-based cohort of lung, breast, colorectal, and liver cancers
Effects of eight neuropsychiatric copy number variants on human brain structure
Many copy number variants (CNVs) confer risk for the same range of neurodevelopmental symptoms and psychiatric conditions including autism and schizophrenia. Yet, to date neuroimaging studies have typically been carried out one mutation at a time, showing that CNVs have large effects on brain anatomy. Here, we aimed to characterize and quantify the distinct brain morphometry effects and latent dimensions across 8 neuropsychiatric CNVs. We analyzed T1-weighted MRI data from clinically and non-clinically ascertained CNV carriers (deletion/duplication) at the 1q21.1 (n = 39/28), 16p11.2 (n = 87/78), 22q11.2 (n = 75/30), and 15q11.2 (n = 72/76) loci as well as 1296 non-carriers (controls). Case-control contrasts of all examined genomic loci demonstrated effects on brain anatomy, with deletions and duplications showing mirror effects at the global and regional levels. Although CNVs mainly showed distinct brain patterns, principal component analysis (PCA) loaded subsets of CNVs on two latent brain dimensions, which explained 32 and 29% of the variance of the 8 Cohen’s d maps. The cingulate gyrus, insula, supplementary motor cortex, and cerebellum were identified by PCA and multi-view pattern learning as top regions contributing to latent dimension shared across subsets of CNVs. The large proportion of distinct CNV effects on brain morphology may explain the small neuroimaging effect sizes reported in polygenic psychiatric conditions. Nevertheless, latent gene brain morphology dimensions will help subgroup the rapidly expanding landscape of neuropsychiatric variants and dissect the heterogeneity of idiopathic conditions
Improved thermal energy utilization through coupled and cascaded cooling cycles
Limited worldwide energy supplies demand the
improved utilization of thermal energy, which is the dominant form of all primary energy sources used today. Large quantities of waste heat are routinely exhausted wherever thermo-mechanical energy conversion occurs, providing an opportunity to improve utilization. Two waste-heat-driven cycles are analyzed: an absorption/compression cascade cooling cycle and a coupled Rankine/compression cycle. The absorption/compression cascade provides an environmentally-sound option for a common approach to thermal energy recovery: the use of absorption cycles for cooling applications. To achieve cooling at temperatures below 0ºC, ammonia-water is the overwhelming choice for the working fluid. However, concerns about the toxicity and flammability of ammonia sometimes limit its application in sensitive arenas. In this study, a lithium bromide-water absorption cycle is coupled with a carbon dioxide vapor compression cycle to realize the benefits of high-lift cooling without the concerns associated with ammonia. This cycle utilizes a waste heat stream at temperatures as low as 150°C to provide cooling at -40°C. The topping absorption cycle achieves a coefficient of performance (COP) of about 0.77, while the bottoming cycle achieves a
COP of about 2.2. The coupled Rankine/compression cycle provides a mechanical expansion and compression approach to achieve thermally activated cooling, again driven by waste heat. The power produced in the turbine of the Rankine cycle is directly coupled to the compressor of a vapor-compression cooling cycle to generate cooling to be utilized for space-conditioning. The refrigerant R245fa is used throughout the cycle. Even with low grade waste heat sources, a Rankine cycle efficiency of about 11-12 percent can be achieved. When coupled to the bottoming compression cycle with a COP of about 2.7, this yields an overall waste heat to cooling conversion efficiency of about 32 percent
at nominal conditions.M.S.Committee Chair: Dr. Srinivas Garimella; Committee Member: Dr. Samuel Graham; Committee Member: Dr. Sheldon Jete
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