Investigation of land-use spectral signatures

A technique was developed to obtain bidirectional reflectance data from natural surfaces by using a folding mirror to transfer the reflected energy from the test surface to a spectroradiometer. The folding mirror was a first surface reflector made by stretching Mylar vacuum coated with aluminum over a light weight frame. The optically folding mirror was positioned over the test surfaces with a moveable platform for both laboratory and field tests. Field tests were conducted using a tethered balloon system to position the folding mirror. A spectroradiometer was designed and built specifically for this investigation. The spectroradiometer had an angular field of view of twenty-four minutes in one axis and ten minutes in the other axis. The radiometer was capable of detecting energies in small bandwidths throughout the electromagnetic spectrum from 0.3 microns to 3.0 microns. Bidirectional reflectance data and variations in the data with source angles were obtained for Saint Augustine grass, Bermuda grass, and a black alluvium soil from the Mississippi River delta

Robust fabrication of electrospun-like polymer mats to direct cell behaviour

Currently, cell culture systems that include nanoscale topography are widely used in order to provide cells additional cues closer to the in vivo environment, seeking to mimic the natural extracellular matrix. Electrospinning is one of the most common techniques to produce nanofiber mats. However, since many sensitive parameters play an important role in the process, a lack of reproducibility is a major drawback. Here we present a simple and robust methodology to prepare reproducible electrospun-like samples. It consists of a polydimethylsiloxane mold reproducing the fiber pattern to solvent-cast a polymer solution and obtain the final sample. To validate this methodology, poly( L-lactic) acid ( PLLA) samples were obtained and, after characterisation, bioactivity and ability to direct cell response were assessed. C2C12 myoblasts developed focal adhesions on the electrospun-like fibers and, when cultured under myogenic differentiation conditions, similar differentiation levels to electrospun PLLA fibers were obtained.The support of ERC through HealInSynergy (306990) and FPU program AP2009-3626 is acknowledged.Ballester Beltrán, J.; Lebourg., MM.; Capella Monsonís, H.; Díaz Lantada, A.; Salmerón Sánchez, M. (2014). Robust fabrication of electrospun-like polymer mats to direct cell behaviour. Biofabrication. 6(3). https://doi.org/10.1088/1758-5082/6/3/035009S6

Genome-Wide Screening of Genes Whose Enhanced Expression Affects Glycogen Accumulation in Escherichia coli

Using a systematic and comprehensive gene expression library (the ASKA library), we have carried out a genome-wide screening of the genes whose increased plasmid-directed expression affected glycogen metabolism in Escherichia coli. Of the 4123 clones of the collection, 28 displayed a glycogen-excess phenotype, whereas 58 displayed a glycogen-deficient phenotype. The genes whose enhanced expression affected glycogen accumulation were classified into various functional categories including carbon sensing, transport and metabolism, general stress and stringent responses, factors determining intercellular communication, aggregative and social behaviour, nitrogen metabolism and energy status. Noteworthy, one-third of them were genes about which little or nothing is known. We propose an integrated metabolic model wherein E. coli glycogen metabolism is highly interconnected with a wide variety of cellular processes and is tightly adjusted to the nutritional and energetic status of the cell. Furthermore, we provide clues about possible biological roles of genes of still unknown functions

Influence of DNA topology on expression of the tdc operon in Escherichia coli K-12

TdcB activity expressed from the chromosomal gene and LacZ expression from single-copy tdc-lacZ transcriptional and translational fusions were measured in Escherichia coli strains harboring mutations in the genes encoding DNA gyrase, topoisomerase I and the HU protein. The pattern of tdc operon expression in these mutants suggests that relaxation of supercoiled DNA enhances tdc transcription in vivo.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47585/1/438_2004_Article_BF00290409.pd

Construction and characterization of oligonucleotide-directed and conventionaltrpR missense mutations

Saturation mutagenesis has been performed on codon 71 of the E. coli trpR gene. These mutations were created by oligonucleotide-directed mutagenesis of a trpR gene fragment within a M13mp cloning vehicle. A Rec-promoted strategy was developed which allowed for positive selection of allele replacement from M13 to chromosomal sequences. This strategy should be applicable to the mutagenesis of many types of proteins. Insufficient homology was postulated as the reason for an inability to successfully recombine the missense mutations onto the chromosome. The CUV107 trpR mutation isolated by Reznikoff and Thornton (1972) was cloned, sequenced and characterized. The CUV107 mutation was found to consist of two nucleotide switches, which would be predicted to result in a single missense mutation, Trp99 $\to$ Arg. A temperature resistant trpPO-lacZ lambda phage was constructed. In vivo $\beta$-galactosidase assays showed that the mutant repressor has a reduced ability to regulate the trp promoter at 30\sp\circC and 42\sp\circC. The mutant protein was overproduced and partially purified. In vitro protection assays showed that the mutant repressor binds trp operator DNA very poorly at 42\sp\circC. Computer analysis indicates that the reduced affinity for trp operator at 30\sp\circC is caused by steric clashes between residue 99 of one monomer and residues 28, 32 and 34 of the other monomer. These steric clashes result in perturbation of the helices of Trp repressor which comprise the HTH-domain

Simulation of tactical alternative responses (STAR)

This thesis presents a stochastic simulation model of ground combat. The tactics represented in the model are explained in detail, and a brief explanation of the SIMSCRIPT programming lan^age used in the model is presented. The model is explained in detail, and the computer routines v/hich make up the model are included. The input requirements for execution of the model are explained in detail so that this thesis might become the initial user's manual for future applications of the model. A typical simulated battle is presented with detailed explanation of the output to enable the reader to better appreciate the potential applications of the model. The current status of the model referenced in the thesis is prior to the version which will be used for production runs.Captain, United States ArmyApproved for public release; distribution is unlimited