848 research outputs found
Air pollutant production by algal cell cultures
The production of phytotoxic air pollutants by cultures of Chlorella vulgaris and Euglena gracilis is considered. Algal and plant culture systems, a fumigation system, and ethylene, ethane, cyanide, and nitrogen oxides assays are discussed. Bean, tobacco, mustard green, cantaloupe and wheat plants all showed injury when fumigated with algal gases for 4 hours. Only coleus plants showed any resistance to the gases. It is found that a closed or recycled air effluent system does not produce plant injury from algal air pollutants
Selective Laser Sintering of Pharmaceutical Printlet Formulations
The purpose of this paper was to investigate the additive manufacturing of pharmaceutical medications through powder bed fusion (PBF), specifically selective laser sintering (SLS) with an objective to achieve printlets with competitive mechanical properties without compromising the drug’s performance in an extended release study. Currently, pills/tablets are made through a combination of mechanical, pressing, and heat application processes in large standardized batches. Using additive manufacturing to make medications offers significant flexibility in personalization for the patient, Just-In-Time manufacture and delivery, and at the point of care, often in rural or underserved areas. SLS is a new method to manufacture pharmaceuticals, but one which has not been well-understood, especially in terms of process parameter effects on printlet quality and performance. In this study, the effects of process input variables related to temperature and laser energy density imparted, in conjunction with relative powder fractions and particle size distributions were studied against printlet quality and performance (both mechanical and pharmaceutical). Results show the fine balance needed to achieve structural integrity while not degrading the drug, and that controlling surface temperatures and particle sizes were the keys to printlet quality/performance
Molecular Beams
Contains reports on five research projects.Lincoln Laboratory (Purchase Order DDL B-00306)United States Air Force (Contract AF19(604)-7400)United States NavyUnited States Arm
RESOLUTION‐RETRIEVING SOURCE‐EFFECT COMPENSATION IN HOLOGRAPHY WITH EXTENDED SOURCES
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/69575/2/APPLAB-7-6-178-1.pd
Comparative Investigations of Social Context-Dependent Dominance in Captive Chimpanzees (Pan troglodytes) and Wild Tibetan Macaques (Macaca thibetana)
Theoretical definitions of dominance, how dominance is structured and organized in nature, and how dominance is measured have varied as investigators seek to classify and organize social systems in gregarious species. Given the variability in behavioral measures and statistical methods used to derive dominance rankings, we conducted a comparative analysis of dominance using existing statistical techniques to analyze dominance ranks, social context-dependent dominance structures, the reliability of statistical analyses, and rank predictability of dominance structures on other social behaviors. We investigated these topics using behavioral data from captive chimpanzees (Pan troglodytes) and wild Tibetan macaques (Macaca thibetana). We used a combination of all-occurrence, focal-animal, and instantaneous scan sampling to collect social, agonistic, and associative data from both species. We analyzed our data to derive dominance ranks, test rank reliability, and assess cross-context predictability using various statistical analyses. Our results indicate context-dependent dominance and individual social roles in the captive chimpanzee group, one broadly defined dominance structure in the Tibetan macaque group, and high within-context analysis reliability but little cross-context predictability. Overall, we suggest this approach is preferable over investigations of dominance where only a few behavioral metrics and statistical analyses are utilized with little consideration of rank reliability or cross-context predictability
Antibacterial Gene Transfer Across the Tree of Life
Though horizontal gene transfer (HGT) is widespread, genes and taxa experience biased rates of transferability. Curiously, independent transmission of homologous DNA to archaea, bacteria, eukaryotes, and viruses is extremely rare and often defies ecological and functional explanations. Here, we demonstrate that a bacterial lysozyme family integrated independently in all domains of life across diverse environments, generating the only glycosyl hydrolase 25 muramidases in plants and archaea. During coculture of a hydrothermal vent archaeon with a bacterial competitor, muramidase transcription is upregulated. Moreover, recombinant lysozyme exhibits broad-spectrum antibacterial action in a dose-dependent manner. Similar to bacterial transfer of antibiotic resistance genes, transfer of a potent antibacterial gene across the universal tree seemingly bestows a niche-transcending adaptation that trumps the barriers against parallel HGT to all domains. The discoveries also comprise the first characterization of an antibacterial gene in archaea and support the pursuit of antibiotics in this underexplored group
Fourier-transform spectroscopy using holographic imaging without computing and with stationary interferometers
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32013/1/0000055.pd
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