NORMAL NASAL GENE EXPRESSION LEVELS USING CDNA ARRAY TECHNOLOGY
Normal Nasal Gene Expression Levels Using cDNA Array Technology.
The nasal epithelium is a target site for chemically-induced toxicity and carcinogenicity. To detect and analyze genetic events which contribute to nasal tumor development, we first defined the gene expressi...
STUDIES OF NORMAL GENE EXPRESSION IN THE RAT NASAL EPITHELIUM USNG CDNA ARRAY TECHNOLOGY
Studies of Normal Gene Expression in the Rat Nasal Epithelium Using cDNA Array
The nasal epithelium is an important target site for chemically-induced toxicity and carcinogenicity .Gene expression data are being used increasingly for studies of such conditions. In or...
Fabrication of high quality cDNA microarray using a small amount of cDNA.
Park, Chan Hee; Jeong, Ha Jin; Jung, Jae Jun; Lee, Gui Yeon; Kim, Sang-Chul; Kim, Tae Soo; Yang, Sang Hwa; Chung, Hyun Cheol; Rha, Sun Young
2004-05-01
DNA microarray technology has become an essential part of biological research. It enables the genome-scale analysis of gene expression in various types of model systems. Manufacturing high quality cDNA microarrays of microdeposition type depends on some key factors including a printing device, spotting pins, glass slides, spotting solution, and humidity during spotting. UsingEthe Microgrid II TAS model printing device, this study defined the optimal conditions for producing high density, high quality cDNA microarrays with the least amount of cDNA product. It was observed that aminosilane-modified slides were superior to other types of surface modified-slides. A humidity of 30+/-3% in a closed environment and the overnight drying of the spotted slides gave the best conditions for arraying. In addition, the cDNA dissolved in 30% DMSO gave the optimal conditions for spotting compared to the 1X ArrayIt, 3X SSC and 50% DMSO. Lastly, cDNA in the concentration range of 100-300 ng/ micro l was determined to be best for arraying and post-processing. Currently, the printing system in this study yields reproducible 9000 spots with a spot size 150 mm diameter, and a 200 nm spot spacing.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Proudnikov, D.; Kirillov, E.; Chumakov, K.
2000-01-01
This paper describes use of a new technology of hybridization with a micro-array of immobilized oligonucleotides for detection and quantification of neurovirulent mutants in Oral Poliovirus Vaccine (OPV). We used a micro-array consisting of three-dimensional gel-elements containing all possible hexamers (total of 4096 probes). Hybridization of fluorescently labelled viral cDNA samples with such microchips resulted in a pattern of spots that was registered and quantified by a computer-linked CCD camera, so that the sequence of the original cDNA could be deduced. The method could reliably identify single point mutations, since each of them affected fluorescence intensity of 12 micro-array elements.more » Micro-array hybridization of DNA mixtures with varying contents of point mutants demonstrated that the method can detect as little as 10% of revertants in a population of vaccine virus. This new technology should be useful for quality control of live viral vaccines, as well as for other applications requiring identification and quantification of point mutations.« less
van Zyl, Leonel; von Arnold, Sara; Bozhkov, Peter; Chen, Yongzhong; Egertsdotter, Ulrika; MacKay, John; Sederoff, Ronald R.; Shen, Jing; Zelena, Lyubov
2002-01-01
Hybridization of labelled cDNA from various cell types with high-density arrays of expressed sequence tags is a powerful technique for investigating gene expression. Few conifer cDNA libraries have been sequenced. Because of the high level of sequence conservation between Pinus and Picea we have investigated the use of arrays from one genus for studies of gene expression in the other. The partial cDNAs from 384 identifiable genes expressed in differentiating xylem of Pinus taeda were printed on nylon membranes in randomized replicates. These were hybridized with labelled cDNA from needles or embryogenic cultures of Pinus taeda, P. sylvestris and Picea abies, and with labelled cDNA from leaves of Nicotiana tabacum. The Spearman correlation of gene expression for pairs of conifer species was high for needles (r2 = 0.78 − 0.86), and somewhat lower for embryogenic cultures (r2 = 0.68 − 0.83). The correlation of gene expression for tobacco leaves and needles of each of the three conifer species was lower but sufficiently high (r2 = 0.52 − 0.63) to suggest that many partial gene sequences are conserved in angiosperms and gymnosperms. Heterologous probing was further used to identify tissue-specific gene expression over species boundaries. To evaluate the significance of differences in gene expression, conventional parametric tests were compared with permutation tests after four methods of normalization. Permutation tests after Z-normalization provide the highest degree of discrimination but may enhance the probability of type I errors. It is concluded that arrays of cDNA from loblolly pine are useful for studies of gene expression in other pines or spruces. PMID:18629264
Identification of the Role of Apoptosis Pathways Potentially Involved in Formaldehyde- Induced Carcinogenesis Using cDNA Arrays.
Formaldehyde (FA) is a genotoxic chemical found in household, medicinal, and industrial products. Although the major source of human exposure is...
Differentiating the Toxicity of Carcinogenic Aldehydes from Noncarcinogenic Aldehydes in the Rat Nose Using cDNA Arrays.
Formaldehyde is a widely used aldehyde in many industrial settings, the tanning process, household products, and is a contaminant in cigarette smoke. H...
Sharpening spots: correcting for bleedover in cDNA array images.
Therneau, Terry; Tschumper, Renee C; Jelinek, Diane
2002-03-01
For cDNA array methods that depend on imaging of a radiolabel, we show that bleedover of one spot onto another, due to the gap between the array and the imaging media, can be a major problem. The images can be sharpened, however, using a blind convolution method based on the EM algorithm. The sharpened images look like a set of donuts, which concurs with our knowledge of the spotting process. Oversharpened images are actually useful as well, in locating the centers of each spot.
Characterization of transformation related genes in oral cancer cells.
Chang, D D; Park, N H; Denny, C T; Nelson, S F; Pe, M
1998-04-16
A cDNA representational difference analysis (cDNA-RDA) and an arrayed filter technique were used to characterize transformation-related genes in oral cancer. From an initial comparison of normal oral epithelial cells and a human papilloma virus (HPV)-immortalized oral epithelial cell line, we obtained 384 differentially expressed gene fragments and arrayed them on a filter. Two hundred and twelve redundant clones were identified by three rounds of back hybridization. Sequence analysis of the remaining clones revealed 99 unique clones corresponding to 69 genes. The expression of these transformation related gene fragments in three nontumorigenic HPV-immortalized oral epithelial cell lines and three oral cancer cell lines were simultaneously monitored using a cDNA array hybridization. Although there was a considerable cell line-to-cell line variability in the expression of these clones, a reliable prediction of their expression could be made from the cDNA array hybridization. Our study demonstrates the utility of combining cDNA-RDA and arrayed filters in high-throughput gene expression difference analysis. The differentially expressed genes identified in this study should be informative in studying oral epithelial cell carcinogenesis.
Gene chips and arrays revealed: a primer on their power and their uses.
Watson, S J; Akil, H
1999-03-01
This article provides an overview and general explanation of the rapidly developing area of gene chips and expression array technology. These are methods targeted at allowing the simultaneous study of thousands of genes or messenger RNAs under various physiological and pathological states. Their technical basis grows from the Human Genome Project. Both methods place DNA strands on glass computer chips (or microscope slides). Expression arrays start with complementary DNA (cDNA) clones derived from the EST data base, whereas Gene Chips synthesize oligonucleotides directly on the chip itself. Both are analyzed using image analysis systems, are capable of reading values from two different individuals at any one site, and can yield quantitative data for thousands of genes or mRNAs per slide. These methods promise to revolutionize molecular biology, cell biology, neuroscience and psychiatry. It is likely that this technology will radically open up our ability to study the actions and structure of the multiple genes involved in the complex genetics of brain disorders.
MOLECULAR CHARACTERIZATION OF ENDOCRINE DISRUPTION IN FISH USING CDNA ARRAYS.
We are developing cDNA macroarrays to measure the induction of gene expression in sheepshead minnows and largemouth bass exposed to anthropogenic chemicals that can mimic the action of endogenous hormones. For sheepshead minnows exposed in aqua, we observed similar genetic profil...
arrayCGHbase: an analysis platform for comparative genomic hybridization microarrays
Menten, Björn; Pattyn, Filip; De Preter, Katleen; Robbrecht, Piet; Michels, Evi; Buysse, Karen; Mortier, Geert; De Paepe, Anne; van Vooren, Steven; Vermeesch, Joris; Moreau, Yves; De Moor, Bart; Vermeulen, Stefan; Speleman, Frank; Vandesompele, Jo
2005-01-01
Background The availability of the human genome sequence as well as the large number of physically accessible oligonucleotides, cDNA, and BAC clones across the entire genome has triggered and accelerated the use of several platforms for analysis of DNA copy number changes, amongst others microarray comparative genomic hybridization (arrayCGH). One of the challenges inherent to this new technology is the management and analysis of large numbers of data points generated in each individual experiment. Results We have developed arrayCGHbase, a comprehensive analysis platform for arrayCGH experiments consisting of a MIAME (Minimal Information About a Microarray Experiment) supportive database using MySQL underlying a data mining web tool, to store, analyze, interpret, compare, and visualize arrayCGH results in a uniform and user-friendly format. Following its flexible design, arrayCGHbase is compatible with all existing and forthcoming arrayCGH platforms. Data can be exported in a multitude of formats, including BED files to map copy number information on the genome using the Ensembl or UCSC genome browser. Conclusion ArrayCGHbase is a web based and platform independent arrayCGH data analysis tool, that allows users to access the analysis suite through the internet or a local intranet after installation on a private server. ArrayCGHbase is available at . PMID:15910681
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hadano, S.; Ishida, Y.; Tomiyasu, H.
1994-09-01
To complete a transcription map of the 1 Mb region in human chromosome 4p16.3 containing the Huntington disease (HD) gene, the isolation of cDNA clones are being performed throughout. Our method relies on a direct screening of the cDNA libraries probed with single copy microclones from 3 YAC clones spanning 1 Mbp of the HD gene region. AC-DNAs were isolated by a preparative pulsed-field gel electrophoresis, amplified by both a single unique primer (SUP)-PCR and a linker ligation PCR, and 6 microclone-DNA libraries were generated. Then, 8,640 microclones from these libraries were independently amplified by PCR, and arrayed onto themore » membranes. 800-900 microclones that were not cross-hybridized with total human and yeast genomic DNA, TAC vector DNA, and ribosomal cDNA on a dot hybridization (putatively carrying single copy sequences) were pooled to make 9 probe pools. A total of {approximately}1.8x10{sup 7} plaques from the human brain cDNA libraries was screened with 9 pool-probes, and then 672 positive cDNA clones were obtained. So far, 597 cDNA clones were defined and arrayed onto a map of the 1 Mbp of the HD gene region by hybridization with HD region-specific cosmid contigs and YAC clones. Further characterization including a DNA sequencing and Northern blot analysis is currently underway.« less
Stec, James; Wang, Jing; Coombes, Kevin; Ayers, Mark; Hoersch, Sebastian; Gold, David L.; Ross, Jeffrey S; Hess, Kenneth R.; Tirrell, Stephen; Linette, Gerald; Hortobagyi, Gabriel N.; Symmans, W. Fraser; Pusztai, Lajos
2005-01-01
We examined how well differentially expressed genes and multigene outcome classifiers retain their class-discriminating values when tested on data generated by different transcriptional profiling platforms. RNA from 33 stage I-III breast cancers was hybridized to both Affymetrix GeneChip and Millennium Pharmaceuticals cDNA arrays. Only 30% of all corresponding gene expression measurements on the two platforms had Pearson correlation coefficient r ≥ 0.7 when UniGene was used to match probes. There was substantial variation in correlation between different Affymetrix probe sets matched to the same cDNA probe. When cDNA and Affymetrix probes were matched by basic local alignment tool (BLAST) sequence identity, the correlation increased substantially. We identified 182 genes in the Affymetrix and 45 in the cDNA data (including 17 common genes) that accurately separated 91% of cases in supervised hierarchical clustering in each data set. Cross-platform testing of these informative genes resulted in lower clustering accuracy of 45 and 79%, respectively. Several sets of accurate five-gene classifiers were developed on each platform using linear discriminant analysis. The best 100 classifiers showed average misclassification error rate of 2% on the original data that rose to 19.5% when tested on data from the other platform. Random five-gene classifiers showed misclassification error rate of 33%. We conclude that multigene predictors optimized for one platform lose accuracy when applied to data from another platform due to missing genes and sequence differences in probes that result in differing measurements for the same gene. PMID:16049308
Morgan, Michael B; Edge, Sara E; Snell, Terry W
2005-01-01
A coral cDNA array containing 32 genes was used to examine the gene expression profiles of coral populations located at four sites that varied with distance from a semi-submerged municipal dump in Castle Harbour, Bermuda (previously identified as a point source of anthropogenic stressors). Genes on the array represent transcripts induced under controlled laboratory conditions to a variety of stressors both natural (temperature, sediment, salinity, darkness) and xenobiotic (heavy metals, pesticides, PAH) in origin. The gene expression profiles produced revealed information about the types of stressors. Consistent with other studies undertaken in Castle Harbour, the coral cDNA array detected responses to heavy metals, sedimentation, as well as oxidative stress.
Tissue Gene Expression Analysis Using Arrayed Normalized cDNA Libraries
Eickhoff, Holger; Schuchhardt, Johannes; Ivanov, Igor; Meier-Ewert, Sebastian; O'Brien, John; Malik, Arif; Tandon, Neeraj; Wolski, Eryk-Witold; Rohlfs, Elke; Nyarsik, Lajos; Reinhardt, Richard; Nietfeld, Wilfried; Lehrach, Hans
2000-01-01
We have used oligonucleotide-fingerprinting data on 60,000 cDNA clones from two different mouse embryonic stages to establish a normalized cDNA clone set. The normalized set of 5,376 clones represents different clusters and therefore, in almost all cases, different genes. The inserts of the cDNA clones were amplified by PCR and spotted on glass slides. The resulting arrays were hybridized with mRNA probes prepared from six different adult mouse tissues. Expression profiles were analyzed by hierarchical clustering techniques. We have chosen radioactive detection because it combines robustness with sensitivity and allows the comparison of multiple normalized experiments. Sensitive detection combined with highly effective clustering algorithms allowed the identification of tissue-specific expression profiles and the detection of genes specifically expressed in the tissues investigated. The obtained results are publicly available (http://www.rzpd.de) and can be used by other researchers as a digital expression reference. [The sequence data described in this paper have been submitted to the EMBL data library under accession nos. AL360374–AL36537.] PMID:10958641
Huether, Alexander; Höpfner, Michael; Sutter, Andreas P; Baradari, Viola; Schuppan, Detlef; Scherübl, Hans
2006-01-01
AIM: To examine the underlying mechanisms of erlotinib-induced growth inhibition in hepatocellular carcinoma (HCC). METHODS: Erlotinib-induced alterations in gene expression were evaluated using cDNA array technology; changes in protein expression and/or protein activation due to erlotinib treatment as well as IGF-1-induced EGFR transactivation were investigated using Western blotting. RESULTS: Erlotinib treatment inhibited the mitogen activated protein (MAP)-kinase pathway and signal transducer of activation and transcription (STAT)-mediated signaling which led to an altered expression of apoptosis and cell cycle regulating genes as demonstrated by cDNA array technology. Overexpression of proapoptotic factors like caspases and gadds associated with a down-regulation of antiapoptotic factors like Bcl-2, Bcl-XL or jun D accounted for erlotinib's potency to induce apoptosis. Downregulation of cell cycle regulators promoting the G1/S-transition and overexpression of cyclin-dependent kinase inhibitors and gadds contributed to the induction of a G1/G0-arrest in response to erlotinib. Furthermore, we displayed the transactivation of EGFR-mediated signaling by the IGF-1-receptor and showed erlotinib’s inhibitory effects on the receptor-receptor cross talk. CONCLUSION: Our study sheds light on the under-standing of the mechanisms of action of EGFR-TK-inhibition in HCC-cells and thus might facilitate the design of combination therapies that act additively or synergistically. Moreover, our data on the pathways responding to erlotinib treatment could be helpful in predicting the responsiveness of tumors to EGFR-TKIs in the future. PMID:16937526
Sakai, Shinya; Mantani, Naoki; Kogure, Toshiaki; Ochiai, Hiroshi; Shimada, Yutaka; Terasawa, Katsutoshi
2002-12-01
Influenza virus is a worldwide health problem with significant economic consequences. To study the gene expression pattern induced by influenza virus infection, it is useful to reveal the pathogenesis of influenza virus infection; but this has not been well examined, especially in vivo study. To assess the influence of influenza virus infection on gene expression in mice, mRNA levels in the lung and tracheal tissue 48 h after infection were investigated by cDNA array analysis. Four-week-old outbred, specific pathogen free strain, ICR female mice were infected by intra-nasal inoculation of a virus solution under ether anesthesia. The mice were sacrificed 48 h after infection and the tracheas and lungs were removed. To determine gene expression, the membrane-based microtechnique with an Atlas cDNA expression array (mouse 1.2 array II) was performed in accordance with the manual provided. We focused on the expression of 46 mRNAs for cell surface antigens. Of these 46 mRNAs that we examined, four (CD1d2 antigen, CD39 antigen-like 1, CD39 antigen-like 3, CD68 antigen) were up-regulated and one (CD36 antigen) was down-regulated. Although further studies are required, these data suggest that these molecules play an important role in influenza virus infection, especially the phase before specific immunity.
Evaluation of Genomic Instability in the Abnormal Prostate
2006-12-01
array CGH maps copy number aberrations relative to the genome sequence by using arrays of BAC or cDNA clones as the hybridization target instead of...data produced from these analyses complicate the interpretation of results . For these reasons, and as outlined by Davies et al., 22 it is desirable...There have been numerous studies of these abnormalities and several techniques, including 9 chromosome painting, array CGH and SNP arrays , have
cDNA Microarray Screening in Food Safety
ROY, SASHWATI; SEN, CHANDAN K
2009-01-01
The cDNA microarray technology and related bioinformatics tools presents a wide range of novel application opportunities. The technology may be productively applied to address food safety. In this mini-review article, we present an update highlighting the late breaking discoveries that demonstrate the vitality of cDNA microarray technology as a tool to analyze food safety with reference to microbial pathogens and genetically modified foods. In order to bring the microarray technology to mainstream food safety, it is important to develop robust user-friendly tools that may be applied in a field setting. In addition, there needs to be a standardized process for regulatory agencies to interpret and act upon microarray-based data. The cDNA microarray approach is an emergent technology in diagnostics. Its values lie in being able to provide complimentary molecular insight when employed in addition to traditional tests for food safety, as part of a more comprehensive battery of tests. PMID:16466843
Construction and application of a bovine immune-endocrine cDNA microarray.
Tao, Wenjing; Mallard, Bonnie; Karrow, Niel; Bridle, Byram
2004-09-01
A variety of commercial DNA arrays specific for humans and rodents are widely available; however, microarrays containing well-characterized genes to study pathway-specific gene expression are not as accessible for domestic animals, such as cattle, sheep and pigs. Therefore, a small-scale application-targeted bovine immune-endocrine cDNA array was developed to evaluate genetic pathways involved in the immune-endocrine axis of cattle during periods of altered homeostasis provoked by physiological or environmental stressors, such as infection, vaccination or disease. For this purpose, 167 cDNA sequences corresponding to immune, endocrine and inflammatory response genes were collected and categorized. Positive controls included 5 housekeeping genes (glyceraldehydes-3-phosphate dehydrogenase, hypoxanthine phosphoribosyltransferase, ribosomal protein L19, beta-actin, beta2-microglobulin) and bovine genomic DNA. Negative controls were a bacterial gene (Rhodococcus equi 17-kDa virulence-associated protein) and a partial sequence of the plasmid pACYC177. In addition, RNA extracted from un-stimulated, as well as superantigen (Staphylococcus aureus enterotoxin-A, S. aureus Cowan Pansorbin Cells) and mitogen-stimulated (LPS, ConA) bovine blood leukocytes was mixed, reverse transcribed and PCR amplified using gene-specific primers. The endocrine-associated genes were amplified from cDNA derived from un-stimulated bovine hypothalamus, pituitary, adrenal and thyroid gland tissues. The array was constructed in 4 repeating grids of 180 duplicated spots by coupling the PCR amplified 213-630 bp gene fragments onto poly-l-lysine coated glass slides. The bovine immune-endocrine arrays were standardized and preliminary gene expression profiles generated using Cy3 and Cy5 labelled cDNA from un-stimulated and ConA (5 microg/ml) stimulated PBMC of 4 healthy Holstein cows (2-4 replicate arrays/cow) in a time course study. Mononuclear cell-derived cytokine and chemokine (IL-2, IL-1alpha, TNFalpha, IFN-gamma, TGFbeta-1, MCP-1, MCP-2 and MIP-3alpha) mRNA exhibited a repeatable and consistently low expression in un-stimulated cells and at least a two-fold increased expression following 6 and 24 h ConA stimulation as compared to 0 h un-stimulated controls. In contrast, expression of antigen presenting molecules, MHC-DR, MHC-DQ and MHC-DY, were consistently at least two-fold lower following 6 and 24 h ConA stimulation. The only endocrine gene with differential expression following ConA stimulation was prolactin. Additionally, due to the high level of genetic homology between ovine, swine and bovine genes, RNA similarly acquired from sheep and pigs was evaluated and similar gene expression patterns were noted. These data demonstrate that this application-targeted array containing a set of well characterized genes can be used to determine the relative gene expression corresponding to immune-endocrine responses of cattle and related species, sheep and pigs.
Blanchard, Raymond K.; Moore, J. Bernadette; Green, Calvert L.; Cousins, Robert J.
2001-01-01
Mammalian nutritional status affects the homeostatic balance of multiple physiological processes and their associated gene expression. Although DNA array analysis can monitor large numbers of genes, there are no reports of expression profiling of a micronutrient deficiency in an intact animal system. In this report, we have tested the feasibility of using cDNA arrays to compare the global changes in expression of genes of known function that occur in the early stages of rodent zinc deficiency. The gene-modulating effects of this deficiency were demonstrated by real-time quantitative PCR measurements of altered mRNA levels for metallothionein 1, zinc transporter 2, and uroguanylin, all of which have been previously documented as zinc-regulated genes. As a result of the low level of inherent noise within this model system and application of a recently reported statistical tool for statistical analysis of microarrays [Tusher, V.G., Tibshirani, R. & Chu, G. (2001) Proc. Natl. Acad. Sci. USA 98, 5116–5121], we demonstrate the ability to reproducibly identify the modest changes in mRNA abundance produced by this single micronutrient deficiency. Among the genes identified by this array profile are intestinal genes that influence signaling pathways, growth, transcription, redox, and energy utilization. Additionally, the influence of dietary zinc supply on the expression of some of these genes was confirmed by real-time quantitative PCR. Overall, these data support the effectiveness of cDNA array expression profiling to investigate the pleiotropic effects of specific nutrients and may provide an approach to establishing markers for assessment of nutritional status. PMID:11717422
Sequence verification as quality-control step for production of cDNA microarrays.
Taylor, E; Cogdell, D; Coombes, K; Hu, L; Ramdas, L; Tabor, A; Hamilton, S; Zhang, W
2001-07-01
To generate cDNA arrays in our core laboratory, we amplified about 2300 PCR products from a human, sequence-verified cDNA clone library. As a quality-control step, we sequenced the PCR products immediately before printing. The sequence information was used to search the GenBank database to confirm the identities. Although these clones were previously sequence verified by the company, we found that only 79% of the clones matched the original database after handling. Our experience strongly indicates the necessity to sequence verify the clones at the final stage before printing on microarray slides and to modify the gene list accordingly.
Estrogen regulation of uterine genes in vivo detected by complementary DNA array.
Andrade, P M; Silva, I D C G; Borra, R C; de Lima, G R; Baracat, E C
2002-05-01
In the present study, our aim was to identify differentially expressed genes involved in estrogen actions at the endometrium level in rats. Thirty adult rats were ovariectomized four days prior to drug administration for 48 days. Rats were divided in 2 groups: I, control and II, conjugated equine estrogens (CCE). Total RNA was isolated from uterus, and differential expression was analyzed by array technology and RT-PCR. A total of 32 candidate genes were shown to be upregulated or downregulated in groups I or II. Among them, differential expression was already confirmed by RT-PCR for IGFBP5, S12, c-kit, and VEGF, genes whose expression was up regulated during CCE therapy, and casein kinase II and serine kinase expression was the same level in both groups. We have demonstrated that cDNA array represents a powerful approach to identify key molecules in the estrogens therapy. A number of the candidates reported here should provide new markers that may contribute to the detection of target estrogen receptor. This information may also aid the development of new approaches to therapeutic intervention.
Morozumi, Takeya; Toki, Daisuke; Eguchi-Ogawa, Tomoko; Uenishi, Hirohide
2011-09-01
Large-scale cDNA-sequencing projects require an efficient strategy for mass sequencing. Here we describe a method for sequencing pooled cDNA clones using a combination of transposon insertion and Gateway technology. Our method reduces the number of shotgun clones that are unsuitable for reconstruction of cDNA sequences, and has the advantage of reducing the total costs of the sequencing project.
Attomole-level Genomics with Single-molecule Direct DNA, cDNA and RNA Sequencing Technologies.
Ozsolak, Fatih
2016-01-01
With the introduction of next-generation sequencing (NGS) technologies in 2005, the domination of microarrays in genomics quickly came to an end due to NGS's superior technical performance and cost advantages. By enabling genetic analysis capabilities that were not possible previously, NGS technologies have started to play an integral role in all areas of biomedical research. This chapter outlines the low-quantity DNA and cDNA sequencing capabilities and applications developed with the Helicos single molecule DNA sequencing technology.
Hook, Sharon E; Skillman, Ann D; Small, Jack A; Schultz, Irvin R
2006-07-01
Determining how gene expression profiles change with toxicant dose will improve the utility of arrays in identifying biomarkers and modes of toxic action. Isogenic rainbow trout, Oncorhyncus mykiss,were exposed to 10, 50 or 100 ng/L ethynylestradiol (a xeno-estrogen) for 7 days. Following exposure hepatic RNA was extracted. Fluorescently labeled cDNA were generated and hybridized against a commercially available Atlantic Salmon/Trout array (GRASP project, University of Victoria) spotted with 16,000 cDNAs. Transcript expression in treated vs control fish was analyzed via Genespring (Silicon Genetics) to identify genes with altered expression, as well as to determine gene clustering patterns that can be used as "expression signatures". Array results were confirmed via qRT PCR. Our analysis indicates that gene expression profiles varied somewhat with dose. Established biomarkers of exposure to estrogenic chemicals, such as vitellogenin, vitelline envelope proteins, and the estrogen receptor alpha, were induced at every dose. Other genes were dose specific, suggesting that different doses induce distinct physiological responses. These findings demonstrate that cDNA microarrays could be used to identify both toxicant class and relative dose.
Display of a maize cDNA library on baculovirus infected insect cells.
Meller Harel, Helene Y; Fontaine, Veronique; Chen, Hongying; Jones, Ian M; Millner, Paul A
2008-08-12
Maize is a good model system for cereal crop genetics and development because of its rich genetic heritage and well-characterized morphology. The sequencing of its genome is well advanced, and new technologies for efficient proteomic analysis are needed. Baculovirus expression systems have been used for the last twenty years to express in insect cells a wide variety of eukaryotic proteins that require complex folding or extensive posttranslational modification. More recently, baculovirus display technologies based on the expression of foreign sequences on the surface of Autographa californica (AcMNPV) have been developed. We investigated the potential of a display methodology for a cDNA library of maize young seedlings. We constructed a full-length cDNA library of young maize etiolated seedlings in the transfer vector pAcTMVSVG. The library contained a total of 2.5 x 10(5) independent clones. Expression of two known maize proteins, calreticulin and auxin binding protein (ABP1), was shown by western blot analysis of protein extracts from insect cells infected with the cDNA library. Display of the two proteins in infected insect cells was shown by selective biopanning using magnetic cell sorting and demonstrated proof of concept that the baculovirus maize cDNA display library could be used to identify and isolate proteins. The maize cDNA library constructed in this study relies on the novel technology of baculovirus display and is unique in currently published cDNA libraries. Produced to demonstrate proof of principle, it opens the way for the development of a eukaryotic in vivo display tool which would be ideally suited for rapid screening of the maize proteome for binding partners, such as proteins involved in hormone regulation or defence.
Informatic selection of a neural crest-melanocyte cDNA set for microarray analysis
Loftus, S. K.; Chen, Y.; Gooden, G.; Ryan, J. F.; Birznieks, G.; Hilliard, M.; Baxevanis, A. D.; Bittner, M.; Meltzer, P.; Trent, J.; Pavan, W.
1999-01-01
With cDNA microarrays, it is now possible to compare the expression of many genes simultaneously. To maximize the likelihood of finding genes whose expression is altered under the experimental conditions, it would be advantageous to be able to select clones for tissue-appropriate cDNA sets. We have taken advantage of the extensive sequence information in the dbEST expressed sequence tag (EST) database to identify a neural crest-derived melanocyte cDNA set for microarray analysis. Analysis of characterized genes with dbEST identified one library that contained ESTs representing 21 neural crest-expressed genes (library 198). The distribution of the ESTs corresponding to these genes was biased toward being derived from library 198. This is in contrast to the EST distribution profile for a set of control genes, characterized to be more ubiquitously expressed in multiple tissues (P < 1 × 10−9). From library 198, a subset of 852 clustered ESTs were selected that have a library distribution profile similar to that of the 21 neural crest-expressed genes. Microarray analysis demonstrated the majority of the neural crest-selected 852 ESTs (Mel1 array) were differentially expressed in melanoma cell lines compared with a non-neural crest kidney epithelial cell line (P < 1 × 10−8). This was not observed with an array of 1,238 ESTs that was selected without library origin bias (P = 0.204). This study presents an approach for selecting tissue-appropriate cDNAs that can be used to examine the expression profiles of developmental processes and diseases. PMID:10430933
MADGE: scalable distributed data management software for cDNA microarrays.
McIndoe, Richard A; Lanzen, Aaron; Hurtz, Kimberly
2003-01-01
The human genome project and the development of new high-throughput technologies have created unparalleled opportunities to study the mechanism of diseases, monitor the disease progression and evaluate effective therapies. Gene expression profiling is a critical tool to accomplish these goals. The use of nucleic acid microarrays to assess the gene expression of thousands of genes simultaneously has seen phenomenal growth over the past five years. Although commercial sources of microarrays exist, investigators wanting more flexibility in the genes represented on the array will turn to in-house production. The creation and use of cDNA microarrays is a complicated process that generates an enormous amount of information. Effective data management of this information is essential to efficiently access, analyze, troubleshoot and evaluate the microarray experiments. We have developed a distributable software package designed to track and store the various pieces of data generated by a cDNA microarray facility. This includes the clone collection storage data, annotation data, workflow queues, microarray data, data repositories, sample submission information, and project/investigator information. This application was designed using a 3-tier client server model. The data access layer (1st tier) contains the relational database system tuned to support a large number of transactions. The data services layer (2nd tier) is a distributed COM server with full database transaction support. The application layer (3rd tier) is an internet based user interface that contains both client and server side code for dynamic interactions with the user. This software is freely available to academic institutions and non-profit organizations at http://www.genomics.mcg.edu/niddkbtc.
Xu, Y; Ehringer, M; Yang, F; Sikela, J M
2001-06-01
Inbred long-sleep (ILS) and short-sleep (ISS) mice show significant central nervous system-mediated differences in sleep time for sedative dose of ethanol and are frequently used as a rodent model for ethanol sensitivity. In this study, we have used complementary DNA (cDNA) array hybridization methodology to identify genes that are differentially expressed between the brains of ILS and ISS mice. To carry out this analysis, we used both the gene discovery array (GDA) and the Mouse GEM 1 Microarray. GDA consists of 18,378 nonredundant mouse cDNA clones on a single nylon filter. Complex probes were prepared from total brain mRNA of ILS or ISS mice by using reverse transcription and 33P labeling. The labeled probes were hybridized in parallel to the gene array filters. Data from GDA experiments were analyzed with SQL-Plus and Oracle 8. The GEM microarray includes 8,730 sequence-verified clones on a glass chip. Two fluorescently labeled probes were used to hybridize a microarray simultaneously. Data from GEM experiments were analyzed by using the GEMTools software package (Incyte). Differentially expressed genes identified from each method were confirmed by relative quantitative reverse transcription-polymerase chain reaction (RT-PCR). A total of 41 genes or expressed sequence tags (ESTs) display significant expression level differences between brains of ILS and ISS mice after GDA, GEM1 hybridization, and quantitative RT-PCR confirmation. Among them, 18 clones were expressed higher in ILS mice, and 23 clones were expressed higher in ISS mice. The individual gene or EST's function and mapping information have been analyzed. This study identified 41 genes that are differentially expressed between brains of ILS and ISS mice. Some of them may have biological relevance in mediation of phenotypic variation between ILS and ISS mice for ethanol sensitivity. This study also demonstrates that parallel gene expression comparison with high-density cDNA arrays is a rapid and efficient way to discover potential genes and pathways involved in alcoholism and alcohol-related physiologic processes.
Hook, Sharon E.; Skillman, Ann D.; Small, Jack A.; Schultz, Irvin R.
2008-01-01
Determining how gene expression profiles change with toxicant dose will improve the utility of arrays in identifying biomarkers and modes of toxic action. Isogenic rainbow trout, Oncorhyncus mykiss, were exposed to 10, 50 or 100 ng/L ethynylestradiol (a xeno-estrogen) for 7 days. Following exposure hepatic RNA was extracted. Fluorescently labeled cDNA were generated and hybridized against a commercially available Atlantic Salmon/Trout array (GRASP project, University of Victoria) spotted with 16,000 cDNAs. Transcript expression in treated vs control fish was analyzed via Genespring (Silicon Genetics) to identify genes with altered expression, as well as to determine gene clustering patterns that can be used as “expression signatures”. Array results were confirmed via qRT PCR. Our analysis indicates that gene expression profiles varied somewhat with dose. Established biomarkers of exposure to estrogenic chemicals, such as vitellogenin, vitelline envelope proteins, and the estrogen receptor alpha, were induced at every dose. Other genes were dose specific, suggesting that diffierent doses induce distinct physiological responses. These findings demonstrate that cDNA microarrays could be used to identify both toxicant class and relative dose. PMID:16725192
Strand-specific transcriptome profiling with directly labeled RNA on genomic tiling microarrays
2011-01-01
Background With lower manufacturing cost, high spot density, and flexible probe design, genomic tiling microarrays are ideal for comprehensive transcriptome studies. Typically, transcriptome profiling using microarrays involves reverse transcription, which converts RNA to cDNA. The cDNA is then labeled and hybridized to the probes on the arrays, thus the RNA signals are detected indirectly. Reverse transcription is known to generate artifactual cDNA, in particular the synthesis of second-strand cDNA, leading to false discovery of antisense RNA. To address this issue, we have developed an effective method using RNA that is directly labeled, thus by-passing the cDNA generation. This paper describes this method and its application to the mapping of transcriptome profiles. Results RNA extracted from laboratory cultures of Porphyromonas gingivalis was fluorescently labeled with an alkylation reagent and hybridized directly to probes on genomic tiling microarrays specifically designed for this periodontal pathogen. The generated transcriptome profile was strand-specific and produced signals close to background level in most antisense regions of the genome. In contrast, high levels of signal were detected in the antisense regions when the hybridization was done with cDNA. Five antisense areas were tested with independent strand-specific RT-PCR and none to negligible amplification was detected, indicating that the strong antisense cDNA signals were experimental artifacts. Conclusions An efficient method was developed for mapping transcriptome profiles specific to both coding strands of a bacterial genome. This method chemically labels and uses extracted RNA directly in microarray hybridization. The generated transcriptome profile was free of cDNA artifactual signals. In addition, this method requires fewer processing steps and is potentially more sensitive in detecting small amount of RNA compared to conventional end-labeling methods due to the incorporation of more fluorescent molecules per RNA fragment. PMID:21235785
Proof of Concept Study to Assess Fetal Gene Expression in Amniotic Fluid by NanoArray PCR
Massingham, Lauren J.; Johnson, Kirby L.; Bianchi, Diana W.; Pei, Shermin; Peter, Inga; Cowan, Janet M.; Tantravahi, Umadevi; Morrison, Tom B.
2011-01-01
Microarray analysis of cell-free RNA in amniotic fluid (AF) supernatant has revealed differential fetal gene expression as a function of gestational age and karyotype. Once informative genes are identified, research moves to a more focused platform such as quantitative reverse transcriptase-PCR. Standardized NanoArray PCR (SNAP) is a recently developed gene profiling technology that enables the measurement of transcripts from samples containing reduced quantities or degraded nucleic acids. We used a previously developed SNAP gene panel as proof of concept to determine whether fetal functional gene expression could be ascertained from AF supernatant. RNA was extracted and converted to cDNA from 19 AF supernatant samples of euploid fetuses between 15 to 20 weeks of gestation, and transcript abundance of 21 genes was measured. Statistically significant differences in expression, as a function of advancing gestational age, were observed for 5 of 21 genes. ANXA5, GUSB, and PPIA showed decreasing gene expression over time, whereas CASC3 and ZNF264 showed increasing gene expression over time. Statistically significantly increased expression of MTOR and STAT2 was seen in female compared with male fetuses. This study demonstrates the feasibility of focused fetal gene expression analysis using SNAP technology. In the future, this technique could be optimized to examine specific genes instrumental in fetal organ system function, which could be a useful addition to prenatal care. PMID:21827969
Huggins, P; Johnson, CK; Schoergendorfer, A; Putta, S; Bathke, AC; Stromberg, AJ; Voss, SR
2011-01-01
The Mexican axolotl (Ambystoma mexicanum) presents an excellent model to investigate mechanisms of brain development that are conserved among vertebrates. In particular, metamorphic changes of the brain can be induced in free-living aquatic juveniles and adults by simply adding thyroid hormone (T4) to rearing water. Whole brains were sampled from juvenile A. mexicanum that were exposed to 0, 8, and 18 days of 50 nM T4, and these were used to isolate RNA and make normalized cDNA libraries for 454 DNA sequencing. A total of 1,875,732 high quality cDNA reads were assembled with existing ESTs to obtain 5,884 new contigs for human RefSeq protein models, and to develop a custom Affymetrix gene expression array (Amby_002) with approximately 20,000 probe sets. The Amby_002 array was used to identify 303 transcripts that differed statistically (p < 0.05, fold change > 1.5) as a function of days of T4 treatment. Further statistical analyses showed that Amby_002 performed concordantly in comparison to an existing, small format expression array. This study introduces a new A. mexicanum microarray resource for the community and the first lists of T4-responsive genes from the brain of a salamander amphibian. PMID:21457787
Huggins, P; Johnson, C K; Schoergendorfer, A; Putta, S; Bathke, A C; Stromberg, A J; Voss, S R
2012-01-01
The Mexican axolotl (Ambystoma mexicanum) presents an excellent model to investigate mechanisms of brain development that are conserved among vertebrates. In particular, metamorphic changes of the brain can be induced in free-living aquatic juveniles and adults by simply adding thyroid hormone (T4) to rearing water. Whole brains were sampled from juvenile A. mexicanum that were exposed to 0, 8, and 18 days of 50 nM T4, and these were used to isolate RNA and make normalized cDNA libraries for 454 DNA sequencing. A total of 1,875,732 high quality cDNA reads were assembled with existing ESTs to obtain 5884 new contigs for human RefSeq protein models, and to develop a custom Affymetrix gene expression array (Amby_002) with approximately 20,000 probe sets. The Amby_002 array was used to identify 303 transcripts that differed statistically (p<0.05, fold change >1.5) as a function of days of T4 treatment. Further statistical analyses showed that Amby_002 performed concordantly in comparison to an existing, small format expression array. This study introduces a new A. mexicanum microarray resource for the community and the first lists of T4-responsive genes from the brain of a salamander amphibian. Copyright © 2011 Elsevier Inc. All rights reserved.
APPLICATION OF DNA MICROARRAYS TO REPRODUCTIVE TOXICOLOGY AND THE DEVELOPMENT OF A TESTIS ARRAY
With the advent of sequence information for entire mammalian genomes, it is now possible to analyze gene expression and gene polymorphisms on a genomic scale. The primary tool for analysis of gene expression is the DNA microarray. We have used commercially available cDNA micro...
Microarrays have the potential to significantly impact our ability to identify toxic hazards by the identification of mechanistically-relevant markers of toxicity. To be useful for risk assessment however, microarray data must be challenged to determine its reliability and inter...
MORPHOLOGIC ANALYSIS CORRELATES WITH GENE EXPRESSION CHANGES IN CULTURED F344 RAT MESOTHELIAL CELLS
The gene expression pattern of mesothelial cells in vitro was determined after 4 or 12 h exposure to the rat mesothelial, kidney and thyroid carcinogen, and oxidative stressor potassium bromate (KBr03). Gene expression changes observed using cDNA arrays indicated oxidative stres...
Rapid and efficient cDNA library screening by self-ligation of inverse PCR products (SLIP).
Hoskins, Roger A; Stapleton, Mark; George, Reed A; Yu, Charles; Wan, Kenneth H; Carlson, Joseph W; Celniker, Susan E
2005-12-02
cDNA cloning is a central technology in molecular biology. cDNA sequences are used to determine mRNA transcript structures, including splice junctions, open reading frames (ORFs) and 5'- and 3'-untranslated regions (UTRs). cDNA clones are valuable reagents for functional studies of genes and proteins. Expressed Sequence Tag (EST) sequencing is the method of choice for recovering cDNAs representing many of the transcripts encoded in a eukaryotic genome. However, EST sequencing samples a cDNA library at random, and it recovers transcripts with low expression levels inefficiently. We describe a PCR-based method for directed screening of plasmid cDNA libraries. We demonstrate its utility in a screen of libraries used in our Drosophila EST projects for 153 transcription factor genes that were not represented by full-length cDNA clones in our Drosophila Gene Collection. We recovered high-quality, full-length cDNAs for 72 genes and variously compromised clones for an additional 32 genes. The method can be used at any scale, from the isolation of cDNA clones for a particular gene of interest, to the improvement of large gene collections in model organisms and the human. Finally, we discuss the relative merits of directed cDNA library screening and RT-PCR approaches.
Ginsberg, Stephen D; Che, Shaoli
2004-08-01
The use of five histochemical stains (cresyl violet, thionin, hematoxylin & eosin, silver stain, and acridine orange) was evaluated in combination with an expression profiling paradigm that included regional and single cell analyses within the hippocampus of post-mortem human brains and adult mice. Adjacent serial sections of human and mouse hippocampus were labeled by histochemistry or neurofilament immunocytochemistry. These tissue sections were used as starting material for regional and single cell microdissection followed by a newly developed RNA amplification procedure (terminal continuation (TC) RNA amplification) and subsequent hybridization to custom-designed cDNA arrays. Results indicated equivalent levels of global hybridization signal intensity and relative expression levels for individual genes for hippocampi stained by cresyl violet, thionin, and hematoxylin & eosin, and neurofilament immunocytochemistry. Moreover, no significant differences existed between the Nissl stains and neurofilament immunocytochemistry for individual CA1 neurons obtained via laser capture microdissection. In contrast, a marked decrement was observed in adjacent hippocampal sections stained for silver stain and acridine orange, both at the level of the regional dissection and at the CA1 neuron population level. Observations made on the cDNA array platform were validated by real-time qPCR using primers directed against beta-actin and glyceraldehyde-3 phosphate dehydrogenase. Thus, this report demonstrated the utility of using specific Nissl stains, but not stains that bind RNA species directly, in both human and mouse brain tissues at the regional and cellular level for state-of-the-art molecular fingerprinting studies.
Hou, Q; Chen, K; Shan, Z
2015-01-01
To construct the cDNA library of the ascites tumor cells of ovarian cancer, which can be used to screen the related antigen for the early diagnosis of ovarian cancer and therapeutic targets of immune treatment. Four cases of ovarian serous cystadenocarcinoma, two cases of ovarian mucinous cystadenocarcinoma, and two cases of ovarian endometrial carcinoma in patients with ascitic tumor cells which were used to construct the cDNA library. To screen the ovarian cancer antigen gene, evaluate the enzyme, and analyze nucleotide sequence, serological analysis of recombinant tumor cDNA expression libraries (SEREX) and suppression subtractive hybridization technique (SSH) techniques were utilized. The detection method of recombinant expression-based serological mini-arrays (SMARTA) was used to detect the ovarian cancer antigen and the positive reaction of 105 cases of ovarian cancer patients and 105 normal women's autoantibodies correspondingly in serum. After two rounds of serologic screening and glycosides sequencing analysis, 59 candidates of ovarian cancer antigen gene fragments were finally identified, which corresponded to 50 genes. They were then divided into six categories: (1) the homologous genes which related to the known ovarian cancer genes, such as BARD 1 gene, etc; (2) the homologous genes which were associated with other tumors, such as TM4SFI gene, etc; (3) the genes which were expressed in a special organization, such as ILF3, FXR1 gene, etc; (4) the genes which were the same with some protein genes of special function, such as TIZ, ClD gene; (5) the homologous genes which possessed the same source with embryonic genes, such as PKHD1 gene, etc; (6) the remaining genes were the unknown genes without the homologous sequence in the gene pool, such as OV-189 genes. SEREX technology combined with SSH method is an effective research strategy which can filter tumor antigen with high specific character; the corresponding autoantibodies of TM4SFl, ClD, TIZ, BARDI, FXRI, and OV-189 gene's recombinant antigen in serum can be regarded as the biomarkers which are used to diagnose ovarian cancer. The combination of multiple antigen detection can improve diagnostic efficiency.
Dendrimeric coating of glass slides for sensitive DNA microarrays analysis
Le Berre, Véronique; Trévisiol, Emmanuelle; Dagkessamanskaia, Adilia; Sokol, Serguei; Caminade, Anne-Marie; Majoral, Jean Pierre; Meunier, Bernard; François, Jean
2003-01-01
Successful use and reliability of microarray technology is highly dependent on several factors, including surface chemistry parameters and accessibility of cDNA targets to the DNA probes fixed onto the surface. Here, we show that functionalisation of glass slides with homemade dendrimers allow production of more sensitive and reliable DNA microarrays. The dendrimers are nanometric structures of size-controlled diameter with aldehyde function at their periphery. Covalent attachment of these spherical reactive chemical structures on amino-silanised glass slides generates a reactive ∼100 Å layer onto which amino-modified DNA probes are covalently bound. This new grafting chemistry leads to the formation of uniform and homogenous spots. More over, probe concentration before spotting could be reduced from 0.2 to 0.02 mg/ml with PCR products and from 20 to 5 µM with 70mer oligonucleotides without affecting signal intensities after hybridisation with Cy3- and Cy5-labelled targets. More interestingly, while the binding capacity of captured probes on dendrimer-activated glass surface (named dendrislides) is roughly similar to other functionalised glass slides from commercial sources, detection sensitivity was 2-fold higher than with other available DNA microarrays. This detection limit was estimated to 0.1 pM of cDNA targets. Altogether, these features make dendrimer-activated slides ideal for manufacturing cost-effective DNA arrays applicable for gene expression and detection of mutations. PMID:12907740
Simplified Microarray Technique for Identifying mRNA in Rare Samples
NASA Technical Reports Server (NTRS)
Almeida, Eduardo; Kadambi, Geeta
2007-01-01
Two simplified methods of identifying messenger ribonucleic acid (mRNA), and compact, low-power apparatuses to implement the methods, are at the proof-of-concept stage of development. These methods are related to traditional methods based on hybridization of nucleic acid, but whereas the traditional methods must be practiced in laboratory settings, these methods could be practiced in field settings. Hybridization of nucleic acid is a powerful technique for detection of specific complementary nucleic acid sequences, and is increasingly being used for detection of changes in gene expression in microarrays containing thousands of gene probes. A traditional microarray study entails at least the following six steps: 1. Purification of cellular RNA, 2. Amplification of complementary deoxyribonucleic acid [cDNA] by polymerase chain reaction (PCR), 3. Labeling of cDNA with fluorophores of Cy3 (a green cyanine dye) and Cy5 (a red cyanine dye), 4. Hybridization to a microarray chip, 5. Fluorescence scanning the array(s) with dual excitation wavelengths, and 6. Analysis of the resulting images. This six-step procedure must be performed in a laboratory because it requires bulky equipment.
Kim, Unkyu; Siegel, Rachael; Ren, Xiaodi; Gunther, Cary S; Gaasterland, Terry; Roeder, Robert G
2003-07-22
The tissue-specific transcriptional coactivator OCA-B is required for antigen-dependent B cell differentiation events, including germinal center formation. However, the identity of OCA-B target genes involved in this process is unknown. This study has used large-scale cDNA arrays to monitor changes in gene expression patterns that accompany mature B cell differentiation. B cell receptor ligation alone induces many genes involved in B cell expansion, whereas B cell receptor and helper T cell costimulation induce genes associated with B cell effector function. OCA-B expression is induced by both B cell receptor ligation alone and helper T cell costimulation, suggesting that OCA-B is involved in B cell expansion as well as B cell function. Accordingly, several genes involved in cell proliferation and signaling, such as Lck, Kcnn4, Cdc37, cyclin D3, B4galt1, and Ms4a11, have been identified as OCA-B-dependent genes. Further studies on the roles played by these genes in B cells will contribute to an understanding of B cell differentiation.
Trapping and Collection of Lymphocytes Using Microspot Array Chip and Magnetic Beads
NASA Astrophysics Data System (ADS)
Hashioka, Shingi; Obata, Tsutomu; Tokimitsu, Yoshiharu; Fujiki, Satoshi; Nakazato, Hiroyoshi; Muraguchi, Atsushi; Kishi, Hiroyuki; Tanino, Katsumi
2006-04-01
A microspot array chip, which has microspots of a magnetic thin film patterned on a glass substrate, was fabricated for trapping individual cells and for measuring their cellular response. The chip was easily fabricated by conventional semiconductor fabrication techniques on a mass production level as a disposable medical device. When a solution of lymphocyte-bound-magnetic beads was poured into the magnetized chip, each lymphocyte was trapped on each microspot of the magnetic thin film. The trapped cells were easily recovered from the chip using a micromanipulator. The micro-spot array chip can be utilized for arraying live cells and for measuring the response of each cell. The chip will be useful for preparing on array of different kinds of cells and for analyzing cellular response at the single cell level. The chip will be particularly useful for detecting antigen-specific B-lymphocytes and antigen-specific antibody complementary deoxyribonucleic acid (cDNA).
High-speed RNA microextraction technology using magnetic oligo-dT beads and lateral magnetophoresis.
Lee, Hwanyong; Jung, Jinhee; Han, Song-I; Han, Ki-Ho
2010-10-21
This paper presents a high-speed RNA microextractor for the direct isolation of RNA from peripheral blood lysate using magnetic oligo-dT beads. The extraction is achieved through lateral magnetophoresis, generated by a ferromagnetic wire array inlaid on a glass substrate. This RNA microextractor separated more than 80% of magnetic beads with a flow rate up to 20 ml h(-1), and the overall extraction procedure was completed within 1 min. The absorbance ratio of RNA to protein (A(260)/A(280)) was >1.7, indicating that the extraction technology yielded nearly pure RNA. The feasibility of this technique was evaluated further for its applicability to reverse transcription polymerase chain reaction (RT-PCR) procedures by performing cDNA synthesis and PCR. The analysis verified that the RNA microextractor is a practical method for easy, rapid, and high-precision RT-PCR using minimal reagent volumes without requiring highly trained personnel. In addition, it can be readily incorporated into genetic analysis procedures for realizing automated on-chip genetic platforms in a micro format.
The Porcelain Crab Transcriptome and PCAD, the Porcelain Crab Microarray and Sequence Database
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tagmount, Abderrahmane; Wang, Mei; Lindquist, Erika
2010-01-27
Background: With the emergence of a completed genome sequence of the freshwater crustacean Daphnia pulex, construction of genomic-scale sequence databases for additional crustacean sequences are important for comparative genomics and annotation. Porcelain crabs, genus Petrolisthes, have been powerful crustacean models for environmental and evolutionary physiology with respect to thermal adaptation and understanding responses of marine organisms to climate change. Here, we present a large-scale EST sequencing and cDNA microarray database project for the porcelain crab Petrolisthes cinctipes. Methodology/Principal Findings: A set of ~;;30K unique sequences (UniSeqs) representing ~;;19K clusters were generated from ~;;98K high quality ESTs from a set ofmore » tissue specific non-normalized and mixed-tissue normalized cDNA libraries from the porcelain crab Petrolisthes cinctipes. Homology for each UniSeq was assessed using BLAST, InterProScan, GO and KEGG database searches. Approximately 66percent of the UniSeqs had homology in at least one of the databases. All EST and UniSeq sequences along with annotation results and coordinated cDNA microarray datasets have been made publicly accessible at the Porcelain Crab Array Database (PCAD), a feature-enriched version of the Stanford and Longhorn Array Databases.Conclusions/Significance: The EST project presented here represents the third largest sequencing effort for any crustacean, and the largest effort for any crab species. Our assembly and clustering results suggest that our porcelain crab EST data set is equally diverse to the much larger EST set generated in the Daphnia pulex genome sequencing project, and thus will be an important resource to the Daphnia research community. Our homology results support the pancrustacea hypothesis and suggest that Malacostraca may be ancestral to Branchiopoda and Hexapoda. Our results also suggest that our cDNA microarrays cover as much of the transcriptome as can reasonably be captured in EST library sequencing approaches, and thus represent a rich resource for studies of environmental genomics.« less
Hafner, Christian; Meyer, Stefanie; Langmann, Thomas; Schmitz, Gerd; Bataille, Frauke; Hagen, Ilja; Becker, Bernd; Roesch, Alexander; Rogler, Gerhard; Landthaler, Michael; Vogt, Thomas
2005-01-01
AIM: Eph receptor tyrosine kinases and their membrane bound receptor-like ligands, the ephrins, represent a bi-directional cell-cell contact signaling system that directs epithelial movements in development. The meaning of this system in the adult human gut is unknown. We investigated the Eph/ephrin mRNA expression in the intestinal epithelium of healthy controls and patients with inflammatory bowel disease (IBD). METHODS: mRNA expression profiles of all Eph/ephrin family members in normal small intestine and colon were established by real-time RT-PCR. In addition, differential expression in IBD was investigated by cDNA array technology, and validated by both real-time RT-PCR and immunohistochemistry. Potential effects of enhanced EphB/ephrin-B signaling were analyzed in an in vitro IEC-6 cell scratch wound model. RESULTS: Human adult intestinal mucosa exhibits a complex pattern of Eph receptors and ephrins. Beside the known prominent co-expression of EphA2 and ephrinA1, we found abundantly co-expressed EphB2 and ephrin-B1/2. Interestingly, cDNA array data, validated by real-time PCR and immunohistochemistry, showed upregulation of ephrin-B2 in both perilesional and lesional intestinal epithelial cells of IBD patients, suggesting a role in epithelial homeostasis. Stimulation of ephrin-B signaling in ephrin-B1/2 expressing rat IEC-6-cells with recombinant EphB1-Fc resulted in a significant dose-dependent acceleration of wound closure. Furthermore, fluorescence microscopy showed that EphB1-Fc induced coordinated migration of wound edge cells is associated with enhanced formation of lamellipodial protrusions into the wound, increased actin stress fiber assembly and production of laminin at the wound edge. CONCLUSION: EphB/ephrin-B signaling might represent a novel protective mechanism that promotes intestinal epithelial wound healing, with potential impact on epithelial restitution in IBD. PMID:15996027
Ozawa, Tatsuhiko; Kondo, Masato; Isobe, Masaharu
2004-01-01
The 3' rapid amplification of cDNA ends (3' RACE) is widely used to isolate the cDNA of unknown 3' flanking sequences. However, the conventional 3' RACE often fails to amplify cDNA from a large transcript if there is a long distance between the 5' gene-specific primer and poly(A) stretch, since the conventional 3' RACE utilizes 3' oligo-dT-containing primer complementary to the poly(A) tail of mRNA at the first strand cDNA synthesis. To overcome this problem, we have developed an improved 3' RACE method suitable for the isolation of cDNA derived from very large transcripts. By using the oligonucleotide-containing random 9mer together with the GC-rich sequence for the suppression PCR technology at the first strand of cDNA synthesis, we have been able to amplify the cDNA from a very large transcript, such as the microtubule-actin crosslinking factor 1 (MACF1) gene, which codes a transcript of 20 kb in size. When there is no splicing variant, our highly specific amplification allows us to perform the direct sequencing of 3' RACE products without requiring cloning in bacterial hosts. Thus, this stepwise 3' RACE walking will help rapid characterization of the 3' structure of a gene, even when it encodes a very large transcript.
Transcriptome-wide targets of alternative splicing by RBM4 and possible role in cancer.
Markus, M Andrea; Yang, Yee Hwa J; Morris, Brian J
2016-04-01
This study determined transcriptome-wide targets of the splicing factor RBM4 using Affymetrix GeneChip(®) Human Exon 1.0 ST Arrays and HeLa cells treated with RBM4-specific siRNA. This revealed 238 transcripts that were targeted for alternative splicing. Cross-linking and immunoprecipitation experiments identified 945 RBM4 targets in mouse HEK293 cells, 39% of which were ascribed to "alternative splicing" by in silico pathway analysis. Mouse embryonic stem cells transfected with Rbm4 siRNA hairpins exhibited reduced colony numbers and size consistent with involvement of RBM4 in cell proliferation. RBM4 cDNA probing of a cancer cDNA array involving 18 different tumor types from 13 different tissues and matching normal tissue found overexpression of RBM4 mRNA (p<0.01) in cervical, breast, lung, colon, ovarian and rectal cancers. Many RBM4 targets we identified have been implicated in these cancers. In conclusion, our findings reveal transcriptome-wide targets of RBM4 and point to potential cancer-related targets and mechanisms that may involve RBM4. Copyright © 2016 Elsevier Inc. All rights reserved.
Edvardsen, Rolf B; Malde, Ketil; Mittelholzer, Christian; Taranger, Geir Lasse; Nilsen, Frank
2011-03-01
The Atlantic cod, Gadus morhua, is an important species both for traditional fishery and increasingly also in fish farming. The Atlantic cod is also under potential threat from various environmental changes such as pollution and climate change, but the biological impact of such changes are not well known, in particular when it comes to sublethal effects that can be difficult to assert. Modern molecular and genomic approaches have revolutionized biological research during the last decade, and offer new avenues to study biological functions and e.g. the impact of anthropogenic activities at different life-stages for a given organism. In order to develop genomic data and genomic tools for Atlantic cod we conducted a program were we constructed 20 cDNA libraries, and produced and analyzed 44006 expressed sequence tags (ESTs) from these. Several tissues are represented in the multiple cDNA libraries, that differ in either sexual maturation or immulogical stimulation. This approach allowed us to identify genes that are expressed in particular tissues, life-stages or in response to specific stimuli, and also gives us information about potential functions of the transcripts. The ESTs were used to construct a 16k cDNA microarray to further investigate the cod transcriptome. Microarray analyses were preformed on pylorus, pituitary gland, spleen and testis of sexually maturing male cod. The four different tissues displayed tissue specific transcriptomes demonstrating that the cDNA array is working as expected and will prove to be a powerful tool in further experiments. Copyright © 2010 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Vukanti, R. V.; Mintz, E. M.; Leff, L. G.
2005-05-01
Bacterial responses to environmental signals are multifactorial and are coupled to changes in gene expression. An understanding of bacterial responses to environmental conditions is possible using microarray expression analysis. In this study, the utility of microarrays for examining changes in gene expression in Escherichia coli under different environmental conditions was assessed. RNA was isolated, hybridized to Affymetrix E. coli Genome 2.0 chips and analyzed using Affymetrix GCOS and Genespring software. Major limiting factors were obtaining enough quality RNA (107-108 cells to get 10μg RNA)and accounting for differences in growth rates under different conditions. Stabilization of RNA prior to isolation and taking extreme precautions while handling RNA were crucial. In addition, use of this method in ecological studies is limited by availability and cost of commercial arrays; choice of primers for cDNA synthesis, reproducibility, complexity of results generated and need to validate findings. This method may be more widely applicable with the development of better approaches for RNA recovery from environmental samples and increased number of available strain-specific arrays. Diligent experimental design and verification of results with real-time PCR or northern blots is needed. Overall, there is a great potential for use of this technology to discover mechanisms underlying organisms' responses to environmental conditions.
Estimating the efficiency of fish cross-species cDNA microarray hybridization.
Cohen, Raphael; Chalifa-Caspi, Vered; Williams, Timothy D; Auslander, Meirav; George, Stephen G; Chipman, James K; Tom, Moshe
2007-01-01
Using an available cross-species cDNA microarray is advantageous for examining multigene expression patterns in non-model organisms, saving the need for construction of species-specific arrays. The aim of the present study was to estimate relative efficiency of cross-species hybridizations across bony fishes, using bioinformatics tools. The methodology may serve also as a model for similar evaluations in other taxa. The theoretical evaluation was done by substituting comparative whole-transcriptome sequence similarity information into the thermodynamic hybridization equation. Complementary DNA sequence assemblages of nine fish species belonging to common families or suborders and distributed across the bony fish taxonomic branch were selected for transcriptome-wise comparisons. Actual cross-species hybridizations among fish of different taxonomic distances were used to validate and eventually to calibrate the theoretically computed relative efficiencies.
Assessing the utility of the Oxford Nanopore MinION for snake venom gland cDNA sequencing.
Hargreaves, Adam D; Mulley, John F
2015-01-01
Portable DNA sequencers such as the Oxford Nanopore MinION device have the potential to be truly disruptive technologies, facilitating new approaches and analyses and, in some cases, taking sequencing out of the lab and into the field. However, the capabilities of these technologies are still being revealed. Here we show that single-molecule cDNA sequencing using the MinION accurately characterises venom toxin-encoding genes in the painted saw-scaled viper, Echis coloratus. We find the raw sequencing error rate to be around 12%, improved to 0-2% with hybrid error correction and 3% with de novo error correction. Our corrected data provides full coding sequences and 5' and 3' UTRs for 29 of 33 candidate venom toxins detected, far superior to Illumina data (13/40 complete) and Sanger-based ESTs (15/29). We suggest that, should the current pace of improvement continue, the MinION will become the default approach for cDNA sequencing in a variety of species.
Assessing the utility of the Oxford Nanopore MinION for snake venom gland cDNA sequencing
Hargreaves, Adam D.
2015-01-01
Portable DNA sequencers such as the Oxford Nanopore MinION device have the potential to be truly disruptive technologies, facilitating new approaches and analyses and, in some cases, taking sequencing out of the lab and into the field. However, the capabilities of these technologies are still being revealed. Here we show that single-molecule cDNA sequencing using the MinION accurately characterises venom toxin-encoding genes in the painted saw-scaled viper, Echis coloratus. We find the raw sequencing error rate to be around 12%, improved to 0–2% with hybrid error correction and 3% with de novo error correction. Our corrected data provides full coding sequences and 5′ and 3′ UTRs for 29 of 33 candidate venom toxins detected, far superior to Illumina data (13/40 complete) and Sanger-based ESTs (15/29). We suggest that, should the current pace of improvement continue, the MinION will become the default approach for cDNA sequencing in a variety of species. PMID:26623194
Large-scale analysis of gene expression using cDNA microarrays promises the
rapid detection of the mode of toxicity for drugs and other chemicals. cDNA
microarrays were used to examine chemically-induced alterations of gene
expression in HepG2 cells exposed to oxidative ...
Friis, Thor Einar; Stephenson, Sally; Xiao, Yin; Whitehead, Jon
2014-01-01
The sheep (Ovis aries) is favored by many musculoskeletal tissue engineering groups as a large animal model because of its docile temperament and ease of husbandry. The size and weight of sheep are comparable to humans, which allows for the use of implants and fixation devices used in human clinical practice. The construction of a complimentary DNA (cDNA) library can capture the expression of genes in both a tissue- and time-specific manner. cDNA libraries have been a consistent source of gene discovery ever since the technology became commonplace more than three decades ago. Here, we describe the construction of a cDNA library using cells derived from sheep bones based on the pBluescript cDNA kit. Thirty clones were picked at random and sequenced. This led to the identification of a novel gene, C12orf29, which our initial experiments indicate is involved in skeletal biology. We also describe a polymerase chain reaction-based cDNA clone isolation method that allows the isolation of genes of interest from a cDNA library pool. The techniques outlined here can be applied in-house by smaller tissue engineering groups to generate tools for biomolecular research for large preclinical animal studies and highlights the power of standard cDNA library protocols to uncover novel genes. PMID:24447069
[Primary culture of cat intestinal epithelial cell and construction of its cDNA library].
Ye, L; Gui-Hua, Z; Kun, Y; Hong-Fa, W; Ting, X; Gong-Zhen, L; Wei-Xia, Z; Yong, C
2017-04-12
Objective To establish the primary cat intestinal epithelial cells (IECs) culture methods and construct the cDNA library for the following yeast two-hybrid experiment, so as to screen the virulence interaction factors among the final host. Methods The primary cat IECs were cultured by the tissue cultivation and combined digestion with collagenase XI and dispase I separately. Then the cat IECs cultured was identified with the morphological observation and cyto-keratin detection, by using goat anti-cyto-keratin monoclonal antibodies. The mRNA of cat IECs was isolated and used as the template to synthesize the first strand cDNA by SMART™ technology, and then the double-strand cDNAs were acquired by LD-PCR, which were subsequently cloned into the plasmid PGADT7-Rec to construct yeast two-hybrid cDNA library in the yeast strain Y187 by homologous recombination. Matchmaker™ Insert Check PCR was used to detect the size distribution of cDNA fragments after the capacity calculation of the cDNA library. Results The comparison of the two cultivation methods indicated that the combined digestion of collagenase XI and dispase I was more effective than the tissue cultivation. The cat IECs system of continuous culture was established and the cat IECs with high purity were harvested for constructing the yeast two-hybrid cDNA library. The library contained 1.1×10 6 independent clones. The titer was 2.8×10 9 cfu/ml. The size of inserted fragments was among 0.5-2.0 kb. Conclusion The yeast two-hybrid cDNA library of cat IECs meets the requirements of further screen research, and this study lays the foundation of screening the Toxoplasma gondii virulence interaction factors among the cDNA libraries of its final hosts.
A novel gene, RSD-3/HSD-3.1, encodes a meiotic-related protein expressed in rat and human testis.
Zhang, Xiaodong; Liu, Huixian; Zhang, Yan; Qiao, Yuan; Miao, Shiying; Wang, Linfang; Zhang, Jianchao; Zong, Shudong; Koide, S S
2003-06-01
The expression of stage-specific genes during spermatogenesis was determined by isolating two segments of rat seminiferous tubule at different stages of the germinal epithelium cycle delineated by transillumination-delineated microdissection, combined with differential display polymerase chain reaction to identify the differential transcripts formed. A total of 22 cDNAs were identified and accepted by GenBank as new expressed sequence tags. One of the expressed sequence tags was radiolabeled and used as a probe to screen a rat testis cDNA library. A novel full-length cDNA composed of 2228 bp, designated as RSD-3 (rat sperm DNA no.3, GenBank accession no. AF094609) was isolated and characterized. The reading frame encodes a polypeptide consisting of 526 amino acid residues, containing a number of DNA binding motifs and phosphorylation sites for PKC, CK-II, and p34cdc2. Northern blot of mRNA prepared from various tissues of adult rats showed that RSD-3 is expressed only in the testis. The initial expression of the RSD-3 gene was detected in the testis on the 30th postnatal day and attained adult level on the 60th postnatal day. Immunolocalization of RSD-3 in germ cells of rat testis showed that its expression is restricted to primary spermatocytes, undergoing meiosis division I. A human testis homologue of RSD-3 cDNA, designated as HSD-3.1 (GenBank accession no. AF144487) was isolated by screening the Human Testis Rapid-Screen arrayed cDNA library panels by RT-PCR. The exon-intron boundaries of HSD-3.1 gene were determined by aligning the cDNA sequence with the corresponding genome sequence. The cDNA consisted of 12 exons that span approximately 52.8 kb of the genome sequence and was mapped to chromosome 14q31.3.
JPRS Report, Science and Technology USSR: Life Sciences.
1990-07-16
4 1 VETERINARY MEDICINE Primary Structure of RNA Polymerase Gene of Foot-and-Mouth Disease Virus ( FMDV ...neering were used to obtain cDNA corresponding to the Primary Structure of RNA Polymerase Gene of RNA polymerase gene to FMDV A 2 2 , with a map of the...Foot-and-Mouth Disease Virus ( FMDV ) A22 primary nucleotide sequence of the cDNA provided. 18400538F Moscow BIOORGANICHESKA YA Analysis of the data
Isolation of candidate genes of Friedreich`s ataxia on chromosome 9q13
DOE Office of Scientific and Technical Information (OSTI.GOV)
Montermini, L.; Zara, F.; Pandolfo, M.
1994-09-01
Friedreich`s ataxia (FRDA) is an autosomal recessive degenerative disease involving the central and peripheral nervous system and the heart. The mutated gene in FRDA has recently been localized within a 450 Kb interval on chromosome 9q13 between the markers D9S202/FR1/FR8. We have been able to confirm such localization for the disease gene by analysis of extended haplotype in consanguineous families. Cases of loss of marker homozygosity, which are likely to be due to ancient recombinations, have been found to involve D9S110, D9S15, and D9S111 on the telomeric side, and FR5 on the centromeric side, while homozygosity was always found formore » a core haplotype including D9S5, FD1, and D9S202. We constructed a YAC contig spanning the region between the telomeric markers and FR5, and cosmids have been obtained from the YACs. In order to isolate transcribed sequences from the FRDA candidate region we are utilizing a combination of approaches, including hybridization of YACs and cosmids to an arrayed human heart cDNA library, cDNA direct selection, and exon amplification. A transcribed sequence near the telomeric end of the region has been isolated by cDNA direct selection using pooled cosmids as genomic template and primary human heart, muscle, brain, liver and placenta cDNAs as cDNA source. We have shown this sequence to be the human equivalent of ZO-2, a tight junction protein previously described in the dog. No mutations of this gene have been found in FRDA subjects. Additional cDNA have recently been isolated and they are currently being evaluated.« less
Zhao, Hongjuan; Hastie, Trevor; Whitfield, Michael L; Børresen-Dale, Anne-Lise; Jeffrey, Stefanie S
2002-01-01
Background T7 based linear amplification of RNA is used to obtain sufficient antisense RNA for microarray expression profiling. We optimized and systematically evaluated the fidelity and reproducibility of different amplification protocols using total RNA obtained from primary human breast carcinomas and high-density cDNA microarrays. Results Using an optimized protocol, the average correlation coefficient of gene expression of 11,123 cDNA clones between amplified and unamplified samples is 0.82 (0.85 when a virtual array was created using repeatedly amplified samples to minimize experimental variation). Less than 4% of genes show changes in expression level by 2-fold or greater after amplification compared to unamplified samples. Most changes due to amplification are not systematic both within one tumor sample and between different tumors. Amplification appears to dampen the variation of gene expression for some genes when compared to unamplified poly(A)+ RNA. The reproducibility between repeatedly amplified samples is 0.97 when performed on the same day, but drops to 0.90 when performed weeks apart. The fidelity and reproducibility of amplification is not affected by decreasing the amount of input total RNA in the 0.3–3 micrograms range. Adding template-switching primer, DNA ligase, or column purification of double-stranded cDNA does not improve the fidelity of amplification. The correlation coefficient between amplified and unamplified samples is higher when total RNA is used as template for both experimental and reference RNA amplification. Conclusion T7 based linear amplification reproducibly generates amplified RNA that closely approximates original sample for gene expression profiling using cDNA microarrays. PMID:12445333
Microarray slide hybridization using fluorescently labeled cDNA.
Ares, Manuel
2014-01-01
Microarray hybridization is used to determine the amount and genomic origins of RNA molecules in an experimental sample. Unlabeled probe sequences for each gene or gene region are printed in an array on the surface of a slide, and fluorescently labeled cDNA derived from the RNA target is hybridized to it. This protocol describes a blocking and hybridization protocol for microarray slides. The blocking step is particular to the chemistry of "CodeLink" slides, but it serves to remind us that almost every kind of microarray has a treatment step that occurs after printing but before hybridization. We recommend making sure of the precise treatment necessary for the particular chemistry used in the slides to be hybridized because the attachment chemistries differ significantly. Hybridization is similar to northern or Southern blots, but on a much smaller scale.
Gómez, Raúl; Castro, Ana; Martínez, Jessica; Rodríguez-García, Víctor; Burgués, Octavio; Tarín, Juan J; Cano, Antonio
2018-06-22
The system integrated by the receptor activator of nuclear factor kappa B (RANK) and its ligand, RANKL, modulates the role of hormones in the genesis and progression of breast tumors. We investigated whether the expression of RANK was related with clinicopathological features of primary endometrial tumors. Immunohistochemistry was used in an endometrial cancer tissue array containing samples from 36 tumors. The amount of RANK mRNA was examined in a tissue scan cDNA array containing cDNA from 40 tumors. Normal endometrium was examined for comparison. Immunohistochemical analyses showed that RANK expression was higher in malignant than in normal endometrium ( p < 0.05). RANK expression was related to histological grade (Pearson correlation index = 0.484, p < 0.001), but not to tumor stage or to age of the women. The gene expression was similar in malignant and normal endometrium. The study of RANK isoforms confirmed that the overall relative abundance of the three clearly identified transcripts was similar in normal and pathological endometrium. RANK protein expression increased from normal to malignant endometrium, and the expression level was related with tumor grade but not with stage or the age of subjects in endometrial cancer. In contrast, similar comparisons showed no change in RANK gene expression.
Hook, Sharon E; Skillman, Ann D; Small, Jack A; Schultz, Irvin R
2006-05-25
The increased availability and use of DNA microarrays has allowed the characterization of gene expression patterns associated with exposure to different toxicants. An important question is whether toxicant induced changes in gene expression in fish are sufficiently diverse to allow for identification of specific modes of action and/or specific contaminants. In theory, each class of toxicant may generate a gene expression profile unique to its mode of toxic action. In this study, isogenic (cloned) rainbow trout Oncorhynchus mykiss were exposed to sublethal levels of a series of model toxicants with varying modes of action, including ethynylestradiol (xeno-estrogen), 2,2,4,4'-tetrabromodiphenyl ether (BDE-47, thyroid active), diquat (oxidant stressor), chromium VI, and benzo[a]pyrene (BaP) for a period of 1-3 weeks. An additional experiment measured trenbolone (anabolic steroid; model androgen) induced gene expression changes in sexually mature female trout. Following exposure, fish were euthanized, livers removed and RNA extracted. Fluorescently labeled cDNA were generated and hybridized against a commercially available Atlantic Salmon/Trout array (GRASP project, University of Victoria) spotted with 16,000 cDNA's. The slides were scanned to measure abundance of a given transcript in each sample relative to controls. Data were analyzed via Genespring (Silicon Genetics) to identify a list of up- and downregulated genes, as well as to determine gene clustering patterns that can be used as "expression signatures". The results indicate each toxicant exposure caused between 64 and 222 genes to be significantly altered in expression. Most genes exhibiting altered expression responded to only one of the toxicants and relatively few were co-expressed in multiple treatments. For example, BaP and Diquat, both of which exert toxicity via oxidative stress, upregulated 28 of the same genes, of over 100 genes altered by either treatment. Other genes associated with steroidogenesis, p450 and estrogen responsive genes appear to be useful for selectively identifying toxicant mode of action in fish, suggesting a link between gene expression profile and mode of toxicity. Our array results showed good agreement with quantitative real time polymerase chain reaction (qRT PCR), which demonstrates that the arrays are an accurate measure of gene expression. The specificity of the gene expression profile in response to a model toxicant, the link between genes with altered expression and mode of toxic action, and the consistency between array and qRT PCR results all suggest that cDNA microarrays have the potential to screen environmental contaminants for biomarkers and mode of toxic action.
Laser capture microdissection: Arcturus(XT) infrared capture and UV cutting methods.
Gallagher, Rosa I; Blakely, Steven R; Liotta, Lance A; Espina, Virginia
2012-01-01
Laser capture microdissection (LCM) is a technique that allows the precise procurement of enriched cell populations from a heterogeneous tissue under direct microscopic visualization. LCM can be used to harvest the cells of interest directly or can be used to isolate specific cells by ablating the unwanted cells, resulting in histologically enriched cell populations. The fundamental components of laser microdissection technology are (a) visualization of the cells of interest via microscopy, (b) transfer of laser energy to a thermolabile polymer with either the formation of a polymer-cell composite (capture method) or transfer of laser energy via an ultraviolet laser to photovolatize a region of tissue (cutting method), and (c) removal of cells of interest from the heterogeneous tissue section. Laser energy supplied by LCM instruments can be infrared (810 nm) or ultraviolet (355 nm). Infrared lasers melt thermolabile polymers for cell capture, whereas ultraviolet lasers ablate cells for either removal of unwanted cells or excision of a defined area of cells. LCM technology is applicable to an array of applications including mass spectrometry, DNA genotyping and loss-of-heterozygosity analysis, RNA transcript profiling, cDNA library generation, proteomics discovery, and signal kinase pathway profiling. This chapter describes the unique features of the Arcturus(XT) laser capture microdissection instrument, which incorporates both infrared capture and ultraviolet cutting technology in one instrument, using a proteomic downstream assay as a model.
The effect of column purification on cDNA indirect labelling for microarrays
Molas, M Lia; Kiss, John Z
2007-01-01
Background The success of the microarray reproducibility is dependent upon the performance of standardized procedures. Since the introduction of microarray technology for the analysis of global gene expression, reproducibility of results among different laboratories has been a major problem. Two of the main contributors to this variability are the use of different microarray platforms and different laboratory practices. In this paper, we address the latter question in terms of how variation in one of the steps of a labelling procedure affects the cDNA product prior to microarray hybridization. Results We used a standard procedure to label cDNA for microarray hybridization and employed different types of column chromatography for cDNA purification. After purifying labelled cDNA, we used the Agilent 2100 Bioanalyzer and agarose gel electrophoresis to assess the quality of the labelled cDNA before its hybridization onto a microarray platform. There were major differences in the cDNA profile (i.e. cDNA fragment lengths and abundance) as a result of using four different columns for purification. In addition, different columns have different efficiencies to remove rRNA contamination. This study indicates that the appropriate column to use in this type of protocol has to be experimentally determined. Finally, we present new evidence establishing the importance of testing the method of purification used during an indirect labelling procedure. Our results confirm the importance of assessing the quality of the sample in the labelling procedure prior to hybridization onto a microarray platform. Conclusion Standardization of column purification systems to be used in labelling procedures will improve the reproducibility of microarray results among different laboratories. In addition, implementation of a quality control check point of the labelled samples prior to microarray hybridization will prevent hybridizing a poor quality sample to expensive micorarrays. PMID:17597522
The effect of column purification on cDNA indirect labelling for microarrays.
Molas, M Lia; Kiss, John Z
2007-06-27
The success of the microarray reproducibility is dependent upon the performance of standardized procedures. Since the introduction of microarray technology for the analysis of global gene expression, reproducibility of results among different laboratories has been a major problem. Two of the main contributors to this variability are the use of different microarray platforms and different laboratory practices. In this paper, we address the latter question in terms of how variation in one of the steps of a labelling procedure affects the cDNA product prior to microarray hybridization. We used a standard procedure to label cDNA for microarray hybridization and employed different types of column chromatography for cDNA purification. After purifying labelled cDNA, we used the Agilent 2100 Bioanalyzer and agarose gel electrophoresis to assess the quality of the labelled cDNA before its hybridization onto a microarray platform. There were major differences in the cDNA profile (i.e. cDNA fragment lengths and abundance) as a result of using four different columns for purification. In addition, different columns have different efficiencies to remove rRNA contamination. This study indicates that the appropriate column to use in this type of protocol has to be experimentally determined. Finally, we present new evidence establishing the importance of testing the method of purification used during an indirect labelling procedure. Our results confirm the importance of assessing the quality of the sample in the labelling procedure prior to hybridization onto a microarray platform. Standardization of column purification systems to be used in labelling procedures will improve the reproducibility of microarray results among different laboratories. In addition, implementation of a quality control check point of the labelled samples prior to microarray hybridization will prevent hybridizing a poor quality sample to expensive micorarrays.
HUNT: launch of a full-length cDNA database from the Helix Research Institute.
Yudate, H T; Suwa, M; Irie, R; Matsui, H; Nishikawa, T; Nakamura, Y; Yamaguchi, D; Peng, Z Z; Yamamoto, T; Nagai, K; Hayashi, K; Otsuki, T; Sugiyama, T; Ota, T; Suzuki, Y; Sugano, S; Isogai, T; Masuho, Y
2001-01-01
The Helix Research Institute (HRI) in Japan is releasing 4356 HUman Novel Transcripts and related information in the newly established HUNT database. The institute is a joint research project principally funded by the Japanese Ministry of International Trade and Industry, and the clones were sequenced in the governmental New Energy and Industrial Technology Development Organization (NEDO) Human cDNA Sequencing Project. The HUNT database contains an extensive amount of annotation from advanced analysis and represents an essential bioinformatics contribution towards understanding of the gene function. The HRI human cDNA clones were obtained from full-length enriched cDNA libraries constructed with the oligo-capping method and have resulted in novel full-length cDNA sequences. A large fraction has little similarity to any proteins of known function and to obtain clues about possible function we have developed original analysis procedures. Any putative function deduced here can be validated or refuted by complementary analysis results. The user can also extract information from specific categories like PROSITE patterns, PFAM domains, PSORT localization, transmembrane helices and clones with GENIUS structure assignments. The HUNT database can be accessed at http://www.hri.co.jp/HUNT.
Frankenberger, Casey; Wu, Xiaolin; Harmon, Jerry; Church, Deanna; Gangi, Lisa M; Munroe, David J; Urzúa, Ulises
2006-01-01
Gene copy number variations occur both in normal cells and in numerous pathologies including cancer and developmental diseases. Array comparative genomic hybridisation (aCGH) is an emerging technology that allows detection of chromosomal gains and losses in a high-resolution format. When aCGH is performed on cDNA and oligonucleotide microarrays, the impact of DNA copy number on gene transcription profiles may be directly compared. We have created an online software tool, WebaCGH, that functions to (i) upload aCGH and gene transcription results from multiple experiments; (ii) identify significant aberrant regions using a local Z-score threshold in user-selected chromosomal segments subjected to smoothing with moving averages; and (iii) display results in a graphical format with full genome and individual chromosome views. In the individual chromosome display, data can be zoomed in/out in both dimensions (i.e. ratio and physical location) and plotted features can have 'mouse over' linking to outside databases to identify loci of interest. Uploaded data can be stored indefinitely for subsequent retrieval and analysis. WebaCGH was created as a Java-based web application using the open-source database MySQL. WebaCGH is freely accessible at http://129.43.22.27/WebaCGH/welcome.htm Xiaolin Wu (forestwu@mail.nih.gov) or Ulises Urzúa (uurzua@med.uchile.cl).
Oikonomopoulos, Spyros; Wang, Yu Chang; Djambazian, Haig; Badescu, Dunarel; Ragoussis, Jiannis
2016-08-24
To assess the performance of the Oxford Nanopore Technologies MinION sequencing platform, cDNAs from the External RNA Controls Consortium (ERCC) RNA Spike-In mix were sequenced. This mix mimics mammalian mRNA species and consists of 92 polyadenylated transcripts with known concentration. cDNA libraries were generated using a template switching protocol to facilitate the direct comparison between different sequencing platforms. The MinION performance was assessed for its ability to sequence the cDNAs directly with good accuracy in terms of abundance and full length. The abundance of the ERCC cDNA molecules sequenced by MinION agreed with their expected concentration. No length or GC content bias was observed. The majority of cDNAs were sequenced as full length. Additionally, a complex cDNA population derived from a human HEK-293 cell line was sequenced on an Illumina HiSeq 2500, PacBio RS II and ONT MinION platforms. We observed that there was a good agreement in the measured cDNA abundance between PacBio RS II and ONT MinION (rpearson = 0.82, isoforms with length more than 700bp) and between Illumina HiSeq 2500 and ONT MinION (rpearson = 0.75). This indicates that the ONT MinION can sequence quantitatively both long and short full length cDNA molecules.
Seliger, Barbara; Dressler, Sven P.; Wang, Ena; Kellner, Roland; Recktenwald, Christian V.; Lottspeich, Friedrich; Marincola, Francesco M.; Baumgärtner, Maja; Atkins, Derek; Lichtenfels, Rudolf
2012-01-01
Results obtained from expression profilings of renal cell carcinoma using different “ome”-based approaches and comprehensive data analysis demonstrated that proteome-based technologies and cDNA microarray analyses complement each other during the discovery phase for disease-related candidate biomarkers. The integration of the respective data revealed the uniqueness and complementarities of the different technologies. While comparative cDNA microarray analyses though restricted to upregulated targets largely revealed genes involved in controlling gene/protein expression (19%) and signal transduction processes (13%), proteomics/PROTEOMEX-defined candidate biomarkers include enzymes of the cellular metabolism (36%), transport proteins (12%) and cell motility/structural molecules (10%). Candidate biomarkers defined by proteomics and PROTEOMEX are frequently shared, whereas the sharing rate between cDNA microarray and proteome-based profilings is limited. Putative candidate biomarkers provide insights into their cellular (dys)function and their diagnostic/prognostic value but still warrant further validation in larger patient numbers. Based on the fact that merely 3 candidate biomarkers were shared by all applied technologies, namely annexin A4, tubulin alpha-1A chain and ubiquitin carboxyl-terminal hydrolase L1 the analysis at a single hierarchical level of biological regulation seems to provide only limited results thus emphasizing the importance and benefit of performing rather combinatorial screenings which can complement the standard clinical predictors. PMID:19235166
Characterizing the stress/defense transcriptome of Arabidopsis
Mahalingam, Ramamurthy; Gomez-Buitrago, AnaMaria; Eckardt, Nancy; Shah, Nigam; Guevara-Garcia, Angel; Day, Philip; Raina, Ramesh; Fedoroff, Nina V
2003-01-01
Background To understand the gene networks that underlie plant stress and defense responses, it is necessary to identify and characterize the genes that respond both initially and as the physiological response to the stress or pathogen develops. We used PCR-based suppression subtractive hybridization to identify Arabidopsis genes that are differentially expressed in response to ozone, bacterial and oomycete pathogens and the signaling molecules salicylic acid (SA) and jasmonic acid. Results We identified a total of 1,058 differentially expressed genes from eight stress cDNA libraries. Digital northern analysis revealed that 55% of the stress-inducible genes are rarely transcribed in unstressed plants and 17% of them were not previously represented in Arabidopsis expressed sequence tag databases. More than two-thirds of the genes in the stress cDNA collection have not been identified in previous studies as stress/defense response genes. Several stress-responsive cis-elements showed a statistically significant over-representation in the promoters of the genes in the stress cDNA collection. These include W- and G-boxes, the SA-inducible element, the abscisic acid response element and the TGA motif. Conclusions The stress cDNA collection comprises a broad repertoire of stress-responsive genes encoding proteins that are involved in both the initial and subsequent stages of the physiological response to abiotic stress and pathogens. This set of stress-, pathogen- and hormone-modulated genes is an important resource for understanding the genetic interactions underlying stress signaling and responses and may contribute to the characterization of the stress transcriptome through the construction of standardized specialized arrays. PMID:12620105
Nuclear Matrix Proteins in Disparity of Prostate Cancer
2011-07-01
using G3PDH 3’ primer and PCR primer 1 followed by two rounds of hybridization. In the first hybridization, the RsaI-digested driver cDNA was mixed...determined using β-actin to confirm the reduced relative abundance of the housekeeping gene after SSH. The SSH nested PCR products were cloned using pCR®2.1...variability of DNA concentration. Additionally, negative and positive controls ( housekeeping genes) from the Ambion™ ArrayControls™ Set were included
Feng, Xiaobin; Gan, Ning; Zhang, Huairong; Yan, Qing; Li, Tianhua; Cao, Yuting; Hu, Futao; Yu, Hongwei; Jiang, Qianli
2015-12-15
A novel type of "dual-potential" electrochemiluminescence (ECL) aptasensor array was fabricated on a homemade screen-printed carbon electrode (SPCE) for simultaneous detection of malachite green (MG) and chloramphenicol (CAP) in one single assay. The SPCE substrate consisted of a common Ag/AgCl reference electrode, carbon counter electrode and two carbon working electrodes (WE1 and WE2). In the system, CdS quantum dots (QDs) were modified on WE1 as cathode ECL emitters and luminol-gold nanoparticles (L-Au NPs) were modified on WE2 as anode ECL emitters. Then the MG aptamer complementary strand (MG cDNA) and CAP aptamer complementary strand (CAP cDNA) were attached on CdS QDs and L-Au NPs, respectively. The cDNA would hybridize with corresponding aptamer that was respectively tagged with cyanine dye (Cy5) (as quenchers of CdS QDs) and chlorogenic acid (CA) (as quenchers of l-Au NPs) using poly(ethylenimine) (PEI) as a bridging agent. PEI could lead to a large number of quenchers on the aptamer, which increased the quenching efficiency. Upon MG and CAP adding, the targets could induce strand release due to the highly affinity of analytes toward aptamers. Meanwhile, it could release the Cy5 and CA, which recovered cathode ECL of CdS QDs and anode ECL of L-Au NPs simultaneously. This "dual-potential" ECL strategy could be used to detect MG and CAP with the linear ranges of 0.1-100 nM and 0.2-150 nM, with detection limits of 0.03 nM and 0.07 nM (at 3sB), respectively. More importantly, this designed method was successfully applied to determine MG and CAP in real fish samples and held great potential in the food analysis. Copyright © 2015 Elsevier B.V. All rights reserved.
Pre-amplification in the context of high-throughput qPCR gene expression experiment.
Korenková, Vlasta; Scott, Justin; Novosadová, Vendula; Jindřichová, Marie; Langerová, Lucie; Švec, David; Šídová, Monika; Sjöback, Robert
2015-03-11
With the introduction of the first high-throughput qPCR instrument on the market it became possible to perform thousands of reactions in a single run compared to the previous hundreds. In the high-throughput reaction, only limited volumes of highly concentrated cDNA or DNA samples can be added. This necessity can be solved by pre-amplification, which became a part of the high-throughput experimental workflow. Here, we focused our attention on the limits of the specific target pre-amplification reaction and propose the optimal, general setup for gene expression experiment using BioMark instrument (Fluidigm). For evaluating different pre-amplification factors following conditions were combined: four human blood samples from healthy donors and five transcripts having high to low expression levels; each cDNA sample was pre-amplified at four cycles (15, 18, 21, and 24) and five concentrations (equivalent to 0.078 ng, 0.32 ng, 1.25 ng, 5 ng, and 20 ng of total RNA). Factors identified as critical for a success of cDNA pre-amplification were cycle of pre-amplification, total RNA concentration, and type of gene. The selected pre-amplification reactions were further tested for optimal Cq distribution in a BioMark Array. The following concentrations combined with pre-amplification cycles were optimal for good quality samples: 20 ng of total RNA with 15 cycles of pre-amplification, 20x and 40x diluted; and 5 ng and 20 ng of total RNA with 18 cycles of pre-amplification, both 20x and 40x diluted. We set up upper limits for the bulk gene expression experiment using gene expression Dynamic Array and provided an easy-to-obtain tool for measuring of pre-amplification success. We also showed that variability of the pre-amplification, introduced into the experimental workflow of reverse transcription-qPCR, is lower than variability caused by the reverse transcription step.
Karjalainen, Hannu M; Sironen, Reijo K; Elo, Mika A; Kaarniranta, Kai; Takigawa, Masaharu; Helminen, Heikki J; Lammi, Mikko J
2003-01-01
Mechanical forces have a profound effect on cartilage tissue and chondrocyte metabolism. Strenuous loading inhibits the cellular metabolism, while optimal level of loading at correct frequency raises an anabolic response in chondrocytes. In this study, we used Atlas Human Cancer cDNA array to investigate mRNA expression profiles in human chondrosarcoma cells stretched 8% for 6 hours at a frequency of 0.5 Hz. In addition, cultures were exposed to continuous and cyclic (0.5 Hz) 5 MPa hydrostatic pressure. Cyclic stretch had a more profound effect on the gene expression profiles than 5 MPa hydrostatic pressure. Several genes involved with the regulation of cell cycle were increased in stretched cells, as well as mRNAs for PDGF-B, glucose-1-phosphate uridylyltransferase, Tiam1, cdc37 homolog, Gem, integrin alpha6, and matrix metalloproteinase-3. Among down-regulated genes were plakoglobin, TGF-alpha, retinoic acid receptor-alpha and Wnt8b. A smaller number of changes was detected after pressure treatments. Plakoglobin was increased under cyclic and continuous 5 MPa hydrostatic pressure, while mitogen-activated protein kinase-9, proliferating cell nuclear antigen, Rad6, CD9 antigen, integrins alphaE and beta8, and vimentin were decreased. Cyclic and continuous pressurization induces a number of specific changes. In conclusion, a different set of genes were affected by three different types of mechanical stimuli applied on chondrosarcoma cells.
Identification of genes differentially expressed in association with acquired cisplatin resistance
Johnsson, A; Zeelenberg, I; Min, Y; Hilinski, J; Berry, C; Howell, S B; Los, G
2000-01-01
The goal of this study was to identify genes whose mRNA levels are differentially expressed in human cells with acquired cisplatin (cDDP) resistance. Using the parental UMSCC10b head and neck carcinoma cell line and the 5.9-fold cDDP-resistant subline, UMSCC10b/Pt-S15, two suppressive subtraction hybridization (SSH) cDNA libraries were prepared. One library represented mRNAs whose levels were increased in the cDDP resistant variant (the UP library), the other one represented mRNAs whose levels were decreased in the resistant cells (the DOWN library). Arrays constructed with inserts recovered from these libraries were hybridized with SSH products to identify truly differentially expressed elements. A total of 51 cDNA fragments present in the UP library and 16 in the DOWN library met the criteria established for differential expression. The sequences of 87% of these cDNA fragments were identified in Genbank. Among the mRNAs in the UP library that were frequently isolated and that showed high levels of differential expression were cytochrome oxidase I, ribosomal protein 28S, elongation factor 1α, α-enolase, stathmin, and HSP70. The approach taken in this study permitted identification of many genes never before linked to the cDDP-resistant phenotype. © 2000 Cancer Research Campaign PMID:10993653
Karsten, Stanislav L.; Van Deerlin, Vivianna M. D.; Sabatti, Chiara; Gill, Lisa H.; Geschwind, Daniel H.
2002-01-01
Archival formalin-fixed, paraffin-embedded and ethanol-fixed tissues represent a potentially invaluable resource for gene expression analysis, as they are the most widely available material for studies of human disease. Little data are available evaluating whether RNA obtained from fixed (archival) tissues could produce reliable and reproducible microarray expression data. Here we compare the use of RNA isolated from human archival tissues fixed in ethanol and formalin to frozen tissue in cDNA microarray experiments. Since an additional factor that can limit the utility of archival tissue is the often small quantities available, we also evaluate the use of the tyramide signal amplification method (TSA), which allows the use of small amounts of RNA. Detailed analysis indicates that TSA provides a consistent and reproducible signal amplification method for cDNA microarray analysis, across both arrays and the genes tested. Analysis of this method also highlights the importance of performing non-linear channel normalization and dye switching. Furthermore, archived, fixed specimens can perform well, but not surprisingly, produce more variable results than frozen tissues. Consistent results are more easily obtainable using ethanol-fixed tissues, whereas formalin-fixed tissue does not typically provide a useful substrate for cDNA synthesis and labeling. PMID:11788730
MASQOT: a method for cDNA microarray spot quality control
Bylesjö, Max; Eriksson, Daniel; Sjödin, Andreas; Sjöström, Michael; Jansson, Stefan; Antti, Henrik; Trygg, Johan
2005-01-01
Background cDNA microarray technology has emerged as a major player in the parallel detection of biomolecules, but still suffers from fundamental technical problems. Identifying and removing unreliable data is crucial to prevent the risk of receiving illusive analysis results. Visual assessment of spot quality is still a common procedure, despite the time-consuming work of manually inspecting spots in the range of hundreds of thousands or more. Results A novel methodology for cDNA microarray spot quality control is outlined. Multivariate discriminant analysis was used to assess spot quality based on existing and novel descriptors. The presented methodology displays high reproducibility and was found superior in identifying unreliable data compared to other evaluated methodologies. Conclusion The proposed methodology for cDNA microarray spot quality control generates non-discrete values of spot quality which can be utilized as weights in subsequent analysis procedures as well as to discard spots of undesired quality using the suggested threshold values. The MASQOT approach provides a consistent assessment of spot quality and can be considered an alternative to the labor-intensive manual quality assessment process. PMID:16223442
Toll like receptors gene expression of human keratinocytes cultured of severe burn injury.
Cornick, Sarita Mac; Noronha, Silvana Aparecida Alves Corrêa de; Noronha, Samuel Marcos Ribeiro de; Cezillo, Marcus V B; Ferreira, Lydia Masako; Gragnani, Alfredo
2014-01-01
To evaluate the expression profile of genes related to Toll Like Receptors (TLR) pathways of human Primary Epidermal keratinocytes of patients with severe burns. After obtaining viable fragments of skin with and without burning, culture hKEP was initiated by the enzymatic method using Dispase (Sigma-Aldrich). These cells were treated with Trizol(r) (Life Technologies) for extraction of total RNA. This was quantified and analyzed for purity for obtaining cDNA for the analysis of gene expression using specific TLR pathways PCR Arrays plates (SA Biosciences). After the analysis of gene expression we found that 21% of these genes were differentially expressed, of which 100% were repressed or hyporegulated. Among these, the following genes (fold decrease): HSPA1A (-58), HRAS (-36), MAP2K3 (-23), TOLLIP (-23), RELA (-18), FOS (-16), and TLR1 (-6.0). This study contributes to the understanding of the molecular mechanisms related to TLR pathways and underlying wound infection caused by the burn. Furthermore, it may provide new strategies to restore normal expression of these genes and thereby change the healing process and improve clinical outcome.
Laser Capture Microdissection for Protein and NanoString RNA analysis
Golubeva, Yelena; Salcedo, Rosalba; Mueller, Claudius; Liotta, Lance A.; Espina, Virginia
2013-01-01
Laser capture microdissection (LCM) allows the precise procurement of enriched cell populations from a heterogeneous tissue, or live cell culture, under direct microscopic visualization. Histologically enriched cell populations can be procured by harvesting cells of interest directly, or isolating specific cells by ablating unwanted cells. The basic components of laser microdissection technology are a) visualization of cells via light microscopy, b) transfer of laser energy to a thermolabile polymer with either the formation of a polymer-cell composite (capture method) or transfer of laser energy via an ultraviolet laser to photovolatize a region of tissue (cutting method), and c) removal of cells of interest from the heterogeneous tissue section. The capture and cutting methods (instruments) for laser microdissection differ in the manner by which cells of interest are removed from the heterogeneous sample. Laser energy in the capture method is infrared (810nm), while in the cutting mode the laser is ultraviolet (355nm). Infrared lasers melt a thermolabile polymer that adheres to the cells of interest, whereas ultraviolet lasers ablate cells for either removal of unwanted cells or excision of a defined area of cells. LCM technology is applicable to an array of applications including mass spectrometry, DNA genotyping and loss-of-heterozygosity analysis, RNA transcript profiling, cDNA library generation, proteomics discovery, and signal kinase pathway profiling. This chapter describes laser capture microdissection using an ArcturusXT instrument for protein LCM sample analysis, and using a mmi CellCut Plus® instrument for RNA analysis via NanoString technology. PMID:23027006
Negative Regulators of Insulin Signaling Revealed in a Genome-Wide Functional Screen
Pitman, Jeffrey L.; Orth, Anthony P.; Gekakis, Nicholas
2009-01-01
Background Type 2 diabetes develops due to a combination of insulin resistance and β-cell failure and current therapeutics aim at both of these underlying causes. Several negative regulators of insulin signaling are known and are the subject of drug discovery efforts. We sought to identify novel contributors to insulin resistance and hence potentially novel targets for therapeutic intervention. Methodology An arrayed cDNA library encoding 18,441 human transcripts was screened for inhibitors of insulin signaling and revealed known inhibitors and numerous potential novel regulators. The novel hits included proteins of various functional classes such as kinases, phosphatases, transcription factors, and GTPase associated proteins. A series of secondary assays confirmed the relevance of the primary screen hits to insulin signaling and provided further insight into their modes of action. Conclusion/Significance Among the novel hits was PALD (KIAA1274, paladin), a previously uncharacterized protein that when overexpressed led to inhibition of insulin's ability to down regulate a FOXO1A-driven reporter gene, reduced upstream insulin-stimulated AKT phosphorylation, and decreased insulin receptor (IR) abundance. Conversely, knockdown of PALD gene expression resulted in increased IR abundance, enhanced insulin-stimulated AKT phosphorylation, and an improvement in insulin's ability to suppress FOXO1A-driven reporter gene activity. The present data demonstrate that the application of arrayed genome-wide screening technologies to insulin signaling is fruitful and is likely to reveal novel drug targets for insulin resistance and the metabolic syndrome. PMID:19727444
Cirelli, C; Tononi, G
1999-06-01
The consequences of sleep and sleep deprivation at the molecular level are largely unexplored. Knowledge of such molecular events is essential to understand the restorative processes occurring during sleep as well as the cellular mechanisms of sleep regulation. Here we review the available data about changes in neural gene expression across different behavioural states using candidate gene approaches such as in situ hybridization and immunocytochemistry. We then describe new techniques for systematic screening of gene expression in the brain, such as subtractive hybridization, mRNA differential display, and cDNA microarray technology, outlining advantages and disadvantages of these methods. Finally, we summarize our initial results of a systematic screening of gene expression in the rat brain across behavioural states using mRNA differential display and cDNA microarray technology. The expression pattern of approximately 7000 genes was analysed in the cerebral cortex of rats after 3 h of spontaneous sleep, 3 h of spontaneous waking, or 3 h of sleep deprivation. While the majority of transcripts were expressed at the same level among these three conditions, 14 mRNAs were modulated by sleep and waking. Six transcripts, four more expressed in waking and two more expressed in sleep, corresponded to novel genes. The eight known transcripts were all expressed at higher levels in waking than in sleep and included transcription factors and mitochondrial genes. A possible role for these known transcripts in mediating neural plasticity during waking is discussed.
Weighted analysis of paired microarray experiments.
Kristiansson, Erik; Sjögren, Anders; Rudemo, Mats; Nerman, Olle
2005-01-01
In microarray experiments quality often varies, for example between samples and between arrays. The need for quality control is therefore strong. A statistical model and a corresponding analysis method is suggested for experiments with pairing, including designs with individuals observed before and after treatment and many experiments with two-colour spotted arrays. The model is of mixed type with some parameters estimated by an empirical Bayes method. Differences in quality are modelled by individual variances and correlations between repetitions. The method is applied to three real and several simulated datasets. Two of the real datasets are of Affymetrix type with patients profiled before and after treatment, and the third dataset is of two-colour spotted cDNA type. In all cases, the patients or arrays had different estimated variances, leading to distinctly unequal weights in the analysis. We suggest also plots which illustrate the variances and correlations that affect the weights computed by our analysis method. For simulated data the improvement relative to previously published methods without weighting is shown to be substantial.
USDA-ARS?s Scientific Manuscript database
Next generation sequencing (NGS) technology was used to analyze the occurrence of viruses in Sorghum almum plants in Florida exhibiting mosaic symptoms. Total RNA was extracted from symptomatic leaves and used as a template for cDNA library preparation. The resulting library was sequenced on an Illu...
Solar array technology evaluation program for SEPS (Solar Electrical Propulsion Stage)
NASA Technical Reports Server (NTRS)
1974-01-01
An evaluation of the technology and the development of a preliminary design for a 25 kilowatt solar array system for solar electric propulsion are discussed. The solar array has a power to weight ratio of 65 watts per kilogram. The solar array system is composed of two wings. Each wing consists of a solar array blanket, a blanket launch storage container, an extension/retraction mast assembly, a blanket tensioning system, an array electrical harness, and hardware for supporting the system for launch and in the operating position. The technology evaluation was performed to assess the applicable solar array state-of-the-art and to define supporting research necessary to achieve technology readiness for meeting the solar electric propulsion system solar array design requirements.
The Implementation of Advanced Solar Array Technology in Future NASA Missions
NASA Technical Reports Server (NTRS)
Piszczor, Michael F.; Kerslake, Thomas W.; Hoffman, David J.; White, Steve; Douglas, Mark; Spence, Brian; Jones, P. Alan
2003-01-01
Advanced solar array technology is expected to be critical in achieving the mission goals on many future NASA space flight programs. Current PV cell development programs offer significant potential and performance improvements. However, in order to achieve the performance improvements promised by these devices, new solar array structures must be designed and developed to accommodate these new PV cell technologies. This paper will address the use of advanced solar array technology in future NASA space missions and specifically look at how newer solar cell technologies impact solar array designs and overall power system performance.
Gritsun, T S; Gould, E A
1998-12-01
In less than 1 month we have constructed an infectious clone of attenuated tick-borne encephalitis virus (strain Vasilchenko) from 100 microl of unpurified virus suspension using long high fidelity PCR and a modified bacterial cloning system. Optimization of the 3' antisense primer concentration was essential to achieve PCR synthesis of an 11 kb cDNA copy of RNA from infectious virus. A novel system utilising two antisense primers, a 14-mer for reverse transcription and a 35-mer for long PCR, produced high yields of genomic length cDNA. Use of low copy number Able K cells and an incubation temperature of 28 degrees C increased the genetic stability of cloned cDNA. Clones containing 11 kb cDNA inserts produced colonies of reduced size, thus providing a positive selection system for full length clones. Sequencing of the infectious clone emphasised the improved fidelity of the method compared with conventional PCR and cloning methods. A simple and rapid strategy for genetic manipulation of the infectious clone is also described. These developments represent a significant advance in recombinant technology and should be applicable to positive stranded RNA viruses which cannot easily be purified or genetically manipulated.
Plasmonic Biosensor Based on Vertical Arrays of Gold Nanoantennas.
Klinghammer, Stephanie; Uhlig, Tino; Patrovsky, Fabian; Böhm, Matthias; Schütt, Julian; Pütz, Nils; Baraban, Larysa; Eng, Lukas M; Cuniberti, Gianaurelio
2018-06-25
Implementing large arrays of gold nanowires as functional elements of a plasmonic biosensor is an important task for future medical diagnostic applications. Here we present a microfluidic-channel-integrated sensor for the label-free detection of biomolecules, relying on localized surface plasmon resonances. Large arrays (∼1 cm 2 ) of vertically aligned and densely packed gold nanorods to receive, locally confine, and amplify the external optical signal are used to allow for reliable biosensing. We accomplish this by monitoring the change of the optical nanostructure resonance in the presence of biomolecules within the tight focus area above the nanoantennas, combined with a surface treatment of the nanowires for a specific binding of the target molecules. As a first application, we detect the binding kinetics of two distinct DNA strands as well as the following hybridization of two complementary strands (cDNA) with different lengths (25 and 100 bp). Upon immobilization, a redshift of 1 nm was detected; further backfilling and hybridization led to a peak shift of additional 2 and 5 nm for 25 and 100 bp, respectively. We believe that this work gives deeper insight into the functional understanding and technical implementation of a large array of gold nanowires for future medical applications.
Phased-array-fed antenna configuration study. Volume 1: Technology assessment
NASA Technical Reports Server (NTRS)
Sorbello, R. M.; Zaghloul, A. I.; Lee, B. S.; Siddiqi, S.; Geller, B. D.; Gerson, H. I.; Srinivas, D. N.
1983-01-01
The status of the technologies for phased-array-fed dual reflector systems is reviewed. The different aspects of these technologies, including optical performances, phased array systems, problems encountered in phased array design, beamforming networks, MMIC design and its incorporation into waveguide systems, reflector antenna structures, and reflector deployment mechanisms are addressed.
Waugh, Caryll; Cromer, Deborah; Grimm, Andrew; Chopra, Abha; Mallal, Simon; Davenport, Miles; Mak, Johnson
2015-04-09
Massive, parallel sequencing is a potent tool for dissecting the regulation of biological processes by revealing the dynamics of the cellular RNA profile under different conditions. Similarly, massive, parallel sequencing can be used to reveal the complexity of viral quasispecies that are often found in the RNA virus infected host. However, the production of cDNA libraries for next-generation sequencing (NGS) necessitates the reverse transcription of RNA into cDNA and the amplification of the cDNA template using PCR, which may introduce artefact in the form of phantom nucleic acids species that can bias the composition and interpretation of original RNA profiles. Using HIV as a model we have characterised the major sources of error during the conversion of viral RNA to cDNA, namely excess RNA template and the RNaseH activity of the polymerase enzyme, reverse transcriptase. In addition we have analysed the effect of PCR cycle on detection of recombinants and assessed the contribution of transfection of highly similar plasmid DNA to the formation of recombinant species during the production of our control viruses. We have identified RNA template concentrations, RNaseH activity of reverse transcriptase, and PCR conditions as key parameters that must be carefully optimised to minimise chimeric artefacts. Using our optimised RT-PCR conditions, in combination with our modified PCR amplification procedure, we have developed a reliable technique for accurate determination of RNA species using NGS technology.
Photovoltaic options for solar electric propulsion
NASA Technical Reports Server (NTRS)
Stella, Paul M.; Flood, Dennis J.
1990-01-01
During the past decade, a number of advances have occurred in solar cell and array technology. These advances have lead to performance improvement for both conventional space arrays and for advanced technology arrays. Performance enhancements have occurred in power density, specific power, and environmental capability. Both state-of-the-art and advanced development cells and array technology are discussed. Present technology will include rigid, rollout, and foldout flexible substrate designs, with silicon and GaAs solar cells. The use of concentrator array systems is also discussed based on both DOD and NASA efforts. The benefits of advanced lightweight array technology, for both near term and far term utilization, and of advanced high efficiency, thin, radiation resistant cells is examined. This includes gallium arsenide on germaniun substrates, indium phosphide, and thin film devices such as copper indium diselenide.
LDL oxidation by THP-1 monocytes: implication of HNP-1, SgIII and DMT-1.
He, Chunyan; Huang, Rui; Du, Fen; Zheng, Fang; Wei, Lei; Wu, Junzhu
2009-04-01
Oxidized low-density lipoprotein (oxLDL) plays an important role in the pathogenesis of atherosclerosis. However, the mechanisms of the initiation and progression of LDL oxidation by cells are still unknown. We investigated the molecular mechanism underlying THP-1 cell-mediated LDL oxidation. LDL oxidation was monitored at 234 nm by detecting the formation of conjugated dienes. cDNA array analysis was applied to profile changes in gene expression of human THP-1 monocytes in response to LDL stimulation. The mRNA and protein levels of secretogranin III (SgIII), divalent metal transporter (DMT-1) and human alpha-defensin 1 (HNP-1) were determined by real-time RT-PCR and Western blotting respectively. Eukaryotic expression vectors containing full-length cDNA sequence of HNP-1 (pEGFP-C1/HNP-1) SgIII (pEGFP-C1/SgIII) or DMT-1 (pEGFP-C1/DMT-1) were constructed and transfected to THP-1 cells. The effects of overexpression of these three genes on THP-1 cell-mediated LDL oxidation were observed. LDL oxidation was most pronounced after LDL was incubated with THP-1 cells for 9 h. 1651 genes in total were detected by cDNA array analysis in THP-1 cells with or without LDL treatment for 9 h. Thirteen genes with >2-fold relative expression difference were identified, including nine genes whose expression was up-regulated and four genes whose expression was down-regulated. Among the up-regulated genes, SgIII, DMT-1 and HNP-1 were reported to be associated with atherosclerosis. The increased mRNA expressions of these three genes were confirmed by real-time RT-PCR. Western blotting analysis demonstrated that protein expressions of SgIII and DMT-1 were also enhanced in THP-1 cells in response to LDL. Furthermore, transient overexpression of HNP-1, SgIII or DMT-1 in THP-1 cells significantly increased THP-1 cell-mediated LDL oxidation. Our data suggest that SgIII, DMT-1 and HNP-1 are implicated in cell-mediated LDL oxidation.
NASA Technical Reports Server (NTRS)
Costogue, E. N.; Young, L. E.; Brandhorst, H. W., Jr.
1978-01-01
Development efforts are reported in detail for: (1) a lightweight solar array system for solar electric propulsion; (2) a high efficiency thin silicon solar cell; (3) conceptual design of 200 W/kg solar arrays; (4) fluorocarbon encapsulation for silicon solar cell array; and (5) technology assessment of concentrator solar arrays.
2011-01-01
Background Common bean is an important legume crop with only a moderate number of short expressed sequence tags (ESTs) made with traditional methods. The goal of this research was to use full-length cDNA technology to develop ESTs that would overlap with the beginning of open reading frames and therefore be useful for gene annotation of genomic sequences. The library was also constructed to represent genes expressed under drought, low soil phosphorus and high soil aluminum toxicity. We also undertook comparisons of the full-length cDNA library to two previous non-full clone EST sets for common bean. Results Two full-length cDNA libraries were constructed: one for the drought tolerant Mesoamerican genotype BAT477 and the other one for the acid-soil tolerant Andean genotype G19833 which has been selected for genome sequencing. Plants were grown in three soil types using deep rooting cylinders subjected to drought and non-drought stress and tissues were collected from both roots and above ground parts. A total of 20,000 clones were selected robotically, half from each library. Then, nearly 10,000 clones from the G19833 library were sequenced with an average read length of 850 nucleotides. A total of 4,219 unigenes were identified consisting of 2,981 contigs and 1,238 singletons. These were functionally annotated with gene ontology terms and placed into KEGG pathways. Compared to other EST sequencing efforts in common bean, about half of the sequences were novel or represented the 5' ends of known genes. Conclusions The present full-length cDNA libraries add to the technological toolbox available for common bean and our sequencing of these clones substantially increases the number of unique EST sequences available for the common bean genome. All of this should be useful for both functional gene annotation, analysis of splice site variants and intron/exon boundary determination by comparison to soybean genes or with common bean whole-genome sequences. In addition the library has a large number of transcription factors and will be interesting for discovery and validation of drought or abiotic stress related genes in common bean. PMID:22118559
Evaluation of space station solar array technology
NASA Technical Reports Server (NTRS)
1972-01-01
The research concerning lightweight solar array assemblies since 1970 is reported. A bibliography of abstracts of documents used for reference during this period is included along with an evaluation of available solar array technology. A list of recommended technology programs is presented.
Emerging Use of Gene Expression Microarrays in Plant Physiology
Wullschleger, Stan D.; Difazio, Stephen P.
2003-01-01
Microarrays have become an important technology for the global analysis of gene expression in humans, animals, plants, and microbes. Implemented in the context of a well-designed experiment, cDNA and oligonucleotide arrays can provide highthroughput, simultaneous analysis of transcript abundance for hundreds, if not thousands, of genes. However, despite widespread acceptance, the use of microarrays as a tool to better understand processes of interest to the plant physiologist is still being explored. To help illustrate current uses of microarrays in the plant sciences, several case studies that we believe demonstrate the emerging application of gene expression arrays in plant physiology weremore » selected from among the many posters and presentations at the 2003 Plant and Animal Genome XI Conference. Based on this survey, microarrays are being used to assess gene expression in plants exposed to the experimental manipulation of air temperature, soil water content and aluminium concentration in the root zone. Analysis often includes characterizing transcript profiles for multiple post-treatment sampling periods and categorizing genes with common patterns of response using hierarchical clustering techniques. In addition, microarrays are also providing insights into developmental changes in gene expression associated with fibre and root elongation in cotton and maize, respectively. Technical and analytical limitations of microarrays are discussed and projects attempting to advance areas of microarray design and data analysis are highlighted. Finally, although much work remains, we conclude that microarrays are a valuable tool for the plant physiologist interested in the characterization and identification of individual genes and gene families with potential application in the fields of agriculture, horticulture and forestry.« less
Wang, Hong; Bi, Yongyi; Tao, Ning; Wang, Chunhong
2005-08-01
To detect the differential expression of cell signal transduction genes associated with benzene poisoning, and to explore the pathogenic mechanisms of blood system damage induced by benzene. Peripheral white blood cell gene expression profile of 7 benzene poisoning patients, including one aplastic anemia, was determined by cDNA microarray. Seven chips from normal workers were served as controls. Cluster analysis of gene expression profile was performed. Among the 4265 target genes, 176 genes associated with cell signal transduction were differentially expressed. 35 up-regulated genes including PTPRC, STAT4, IFITM1 etc were found in at least 6 pieces of microarray; 45 down-regulated genes including ARHB, PPP3CB, CDC37 etc were found in at least 5 pieces of microarray. cDNA microarray technology is an effective technique for screening the differentially expressed genes of cell signal transduction. Disorder in cell signal transduction may play certain role in the pathogenic mechanism of benzene poisoning.
Nolden, T; Pfaff, F; Nemitz, S; Freuling, C M; Höper, D; Müller, T; Finke, Stefan
2016-04-05
Reverse genetics approaches are indispensable tools for proof of concepts in virus replication and pathogenesis. For negative strand RNA viruses (NSVs) the limited number of infectious cDNA clones represents a bottleneck as clones are often generated from cell culture adapted or attenuated viruses, with limited potential for pathogenesis research. We developed a system in which cDNA copies of complete NSV genomes were directly cloned into reverse genetics vectors by linear-to-linear RedE/T recombination. Rapid cloning of multiple rabies virus (RABV) full length genomes and identification of clones identical to field virus consensus sequence confirmed the approache's reliability. Recombinant viruses were recovered from field virus cDNA clones. Similar growth kinetics of parental and recombinant viruses, preservation of field virus characters in cell type specific replication and virulence in the mouse model were confirmed. Reduced titers after reporter gene insertion indicated that the low level of field virus replication is affected by gene insertions. The flexibility of the strategy was demonstrated by cloning multiple copies of an orthobunyavirus L genome segment. This important step in reverse genetics technology development opens novel avenues for the analysis of virus variability combined with phenotypical characterization of recombinant viruses at a clonal level.
Innate and adaptive immunity gene expression of human keratinocytes cultured of severe burn injury.
Noronha, Silvana Aparecida Alves Corrêa de; Noronha, Samuel Marcos Ribeiro de; Lanziani, Larissa Elias; Ferreira, Lydia Masako; Gragnani, Alfredo
2014-01-01
Evaluate the expression profile of genes related to Innate and Adaptive Immune System (IAIS) of human Primary Epidermal keratinocytes (hPEKP) of patients with severe burns. After obtaining viable fragments of skin with and without burning, culture hKEP was initiated by the enzymatic method using Dispase (Sigma-Aldrich). These cells were treated with Trizol(r) (Life Technologies) for extraction of total RNA. This was quantified and analyzed for purity for obtaining cDNA for the analysis of gene expression using specific IAIS PCR Arrays plates (SA Biosciences). After the analysis of gene expression we found that 63% of these genes were differentially expressed, of which 77% were repressed and 23% were hyper-regulated. Among these, the following genes (fold increase or decrease): IL8 (41), IL6 (32), TNF (-92), HLA-E (-86), LYS (-74), CCR6 (- 73), CD86 (-41) and HLA-A (-35). This study contributes to the understanding of the molecular mechanisms underlying wound infection caused by the burn. Furthermore, it may provide new strategies to restore normal expression of these genes and thereby change the healing process and improve clinical outcome.
Beldade, P; McMillan, W O; Papanicolaou, A
2008-02-01
Technological and conceptual advances of the last decade have led to an explosion of genomic data and the emergence of new research avenues. Evolutionary and ecological functional genomics, with its focus on the genes that affect ecological success and adaptation in natural populations, benefits immensely from a phylogenetically widespread sampling of biological patterns and processes. Among those organisms outside established model systems, butterflies offer exceptional opportunities for multidisciplinary research on the processes generating and maintaining variation in ecologically relevant traits. Here we highlight research on wing color pattern variation in two groups of Nymphalid butterflies, the African species Bicyclus anynana (subfamily Satyrinae) and species of the South American genus Heliconius (subfamily Heliconiinae), which are emerging as important systems for studying the nature and origins of functional diversity. Growing genomic resources including genomic and cDNA libraries, dense genetic maps, high-density gene arrays, and genetic transformation techniques are extending current gene mapping and expression profiling analysis and enabling the next generation of research questions linking genes, development, form, and fitness. Efforts to develop such resources in Bicyclus and Heliconius underscore the general challenges facing the larger research community and highlight the need for a community-wide effort to extend ongoing functional genomic research on butterflies.
NASA Technical Reports Server (NTRS)
Stankovic, B.; Vian, A.; Henry-Vian, C.; Davies, E.
2000-01-01
Localized wounding of one leaf in intact tomato (Lycopersicon esculentum Mill.) plants triggers rapid systemic transcriptional responses that might be involved in defense. To better understand the mechanism(s) of intercellular signal transmission in wounded tomatoes, and to identify the array of genes systemically up-regulated by wounding, a subtractive cDNA library for wounded tomato leaves was constructed. A novel cDNA clone (designated LebZIP1) encoding a DNA-binding protein was isolated and identified. This clone appears to be encoded by a single gene, and belongs to the family of basic leucine zipper domain (bZIP) transcription factors shown to be up-regulated by cold and dark treatments. Analysis of the mRNA levels suggests that the transcript for LebZIP1 is both organ-specific and up-regulated by wounding. In wounded wild-type tomatoes, the LebZIP1 mRNA levels in distant tissue were maximally up-regulated within only 5 min following localized wounding. Exogenous abscisic acid (ABA) prevented the rapid wound-induced increase in LebZIP1 mRNA levels, while the basal levels of LebZIP1 transcripts were higher in the ABA mutants notabilis (not), sitiens (sit), and flacca (flc), and wound-induced increases were greater in the ABA-deficient mutants. Together, these results suggest that ABA acts to curtail the wound-induced synthesis of LebZIP1 mRNA.
Development of an Ultraflex-Based Thin Film Solar Array for Space Applications
NASA Technical Reports Server (NTRS)
White, Steve; Douglas, Mark; Spence, Brian; Jones, P. Alan; Piszczor, Michael F.
2003-01-01
As flexible thin film photovoltaic (FTFPV) cell technology is developed for space applications, integration into a viable solar array structure that optimizes the attributes of this cell technology is critical. An advanced version of ABLE'sS UltraFlex solar array platform represents a near-term, low-risk approach to demonstrating outstanding array performance with the implementation of FTFPV technology. Recent studies indicate that an advanced UltraFlex solar array populated with 15% efficient thin film cells can achieve over 200 W/kg EOL. An overview on the status of hardware development and the future potential of this technology is presented.
Myohara, Maroko; Niva, Cintia Carla; Lee, Jae Min
2006-08-01
To identify genes specifically activated during annelid regeneration, suppression subtractive hybridization was performed with cDNAs from regenerating and intact Enchytraeus japonensis, a terrestrial oligochaete that can regenerate a complete organism from small body fragments within 4-5 days. Filter array screening subsequently revealed that about 38% of the forward-subtracted cDNA clones contained genes that were upregulated during regeneration. Two hundred seventy-nine of these clones were sequenced and found to contain 165 different sequences (79 known and 86 unknown). Nine clones were fully sequenced and four of these sequences were matched to known genes for glutamine synthetase, glucosidase 1, retinal protein 4, and phosphoribosylaminoimidazole carboxylase, respectively. The remaining five clones encoded an unknown open-reading frame. The expression levels of these genes were highest during blastema formation. Our present results, therefore, demonstrate the great potential of annelids as a new experimental subject for the exploration of unknown genes that play critical roles in animal regeneration.
Mass properties survey of solar array technologies
NASA Technical Reports Server (NTRS)
Kraus, Robert
1991-01-01
An overview of the technologies, electrical performance, and mass characteristics of many of the presently available and the more advanced developmental space solar array technologies is presented. Qualitative trends and quantitative mass estimates as total array output power is increased from 1 kW to 5 kW at End of Life (EOL) from a single wing are shown. The array technologies are part of a database supporting an ongoing solar power subsystem model development for top level subsystem and technology analyses. The model is used to estimate the overall electrical and thermal performance of the complete subsystem, and then calculate the mass and volume of the array, batteries, power management, and thermal control elements as an initial sizing. The array types considered here include planar rigid panel designs, flexible and rigid fold-out planar arrays, and two concentrator designs, one with one critical axis and the other with two critical axes. Solar cell technologies of Si, GaAs, and InP were included in the analyses. Comparisons were made at the array level; hinges, booms, harnesses, support structures, power transfer, and launch retention mountings were included. It is important to note that the results presented are approximations, and in some cases revised or modified performance and mass estimates of specific designs.
NASA advanced space photovoltaic technology-status, potential and future mission applications
NASA Technical Reports Server (NTRS)
Flood, Dennis J.; Piszczor, Michael, Jr.; Stella, Paul M.; Bennett, Gary L.
1989-01-01
The NASA program in space photovoltaic research and development encompasses a wide range of emerging options for future space power systems, and includes both cell and array technology development. The long range goals are to develop technology capable of achieving 300 W/kg for planar arrays, and 300 W/sq m for concentrator arrays. InP and GaAs planar and concentrator cell technologies are under investigation for their potential high efficiency and good radiation resistance. The Advanced Photovoltaic Solar Array (APSA) program is a near term effort aimed at demonstrating 130 W/kg beginning of life specific power using thin (62 micrometer) silicon cells. It is intended to be technology transparent to future high efficiency cells and provides the baseline for development of the 300 W/kg array.
Construction of C35 gene bait recombinants and T47D cell cDNA library.
Yin, Kun; Xu, Chao; Zhao, Gui-Hua; Liu, Ye; Xiao, Ting; Zhu, Song; Yan, Ge
2017-11-20
C35 is a novel tumor biomarker associated with metastasis progression. To investigate the interaction factors of C35 in its high expressed breast cancer cell lines, we constructed bait recombinant plasmids of C35 gene and T47D cell cDNA library for yeast two-hybrid screening. Full length C35 sequences were subcloned using RT-PCR from cDNA template extracted from T47D cells. Based on functional domain analysis, the full-length C35 1-348bp was also truncated into two fragments C351-153bp and C35154-348bp to avoid auto-activation. The three kinds of C35 genes were successfully amplified and inserted into pGBKT7 to construct bait recombinant plasmids pGBKT7-C351-348bp, pGBKT7-C351-153bp and pGBKT7-C35154-348bp, then transformed into Y187 yeast cells by the lithium acetate method. Auto-activation and toxicity of C35 baits were detected using nutritional deficient medium and X-α-Gal assays. The T47D cell ds cDNA was generated by SMART TM technology and the library was constructed using in vivo recombination-mediated cloning in the AH109 yeast strain using a pGADT7-Rec plasmid. The transformed Y187/pGBKT7-C351-348bp line was intensively inhibited while the truncated Y187/pGBKT7-C35 lines had no auto-activation and toxicity in yeast cells. The titer of established cDNA library was 2 × 10 7 pfu/mL with high transformation efficiency of 1.4 × 10 6 , and the insert size of ds cDNA was distributed homogeneously between 0.5-2.0 kb. Our research generated a T47D cell cDNA library with high titer, and the constructed two C35 "baits" contained a respective functional immunoreceptor tyrosine based activation motif (ITAM) and the conserved last four amino acids Cys-Ile-Leu-Val (CILV) motif, and therefore laid a foundation for screening the C35 interaction factors in a BC cell line.
Expression profiling suggests a regulatory role of gallbladder in lipid homeostasis
Yuan, Zuo-Biao; Han, Tian-Quan; Jiang, Zhao-Yan; Fei, Jian; Zhang, Yi; Qin, Jian; Tian, Zhi-Jie; Shang, Jun; Jiang, Zhi-Hong; Cai, Xing-Xing; Jiang, Yu; Zhang, Sheng-Dao; Jin, Gang
2005-01-01
AIM: To examine expression profile of gallbladder using microarray and to investigate the role of gallbladder in lipid homeostasis. METHODS: 33P-labelled cDNA derived from total RNA of gallbladder tissue was hybridized to a cDNA array representing 17000 cDNA clusters. Genes with intensities ≥2 and variation <0.33 between two samples were considered as positive signals with subtraction of background chosen from an area where no cDNA was spotted. The average gray level of two gallbladders was adopted to analyze its bioinformatics. Identified target genes were confirmed by touch-down polymerase chain reaction and sequencing. RESULTS: A total of 11 047 genes expressed in normal gallbladder, which was more than that predicted by another author, and the first 10 genes highly expressed (high gray level in hybridization image), e.g., ARPC5 (2225.88±90.46), LOC55972 (2220.32±446.51) and SLC20A2 (1865.21±98.02), were related to the function of smooth muscle contraction and material transport. Meanwhile, 149 lipid-related genes were expressed in the gallbladder, 89 of which were first identified (with gray level in hybridization image), e.g., FASN (11.42±2.62), APOD (92.61±8.90) and CYP21A2 (246.11±42.36), and they were involved in each step of lipid metabolism pathway. In addition, 19 of those 149 genes were gallstone candidate susceptibility genes (with gray level in hybridization image), e.g., HMGCR (10.98±0.31), NPC1 (34.88±12.12) and NR1H4 (16.8±0.65), which were previously thought to be expressed in the liver and/or intestine tissue only. CONCLUSION: Gallbladder expresses 11 047 genes and takes part in lipid homeostasis. PMID:15810076
Genomic resources for Myzus persicae: EST sequencing, SNP identification, and microarray design
Ramsey, John S; Wilson, Alex CC; de Vos, Martin; Sun, Qi; Tamborindeguy, Cecilia; Winfield, Agnese; Malloch, Gaynor; Smith, Dawn M; Fenton, Brian; Gray, Stewart M; Jander, Georg
2007-01-01
Background The green peach aphid, Myzus persicae (Sulzer), is a world-wide insect pest capable of infesting more than 40 plant families, including many crop species. However, despite the significant damage inflicted by M. persicae in agricultural systems through direct feeding damage and by its ability to transmit plant viruses, limited genomic information is available for this species. Results Sequencing of 16 M. persicae cDNA libraries generated 26,669 expressed sequence tags (ESTs). Aphids for library construction were raised on Arabidopsis thaliana, Nicotiana benthamiana, Brassica oleracea, B. napus, and Physalis floridana (with and without Potato leafroll virus infection). The M. persicae cDNA libraries include ones made from sexual and asexual whole aphids, guts, heads, and salivary glands. In silico comparison of cDNA libraries identified aphid genes with tissue-specific expression patterns, and gene expression that is induced by feeding on Nicotiana benthamiana. Furthermore, 2423 genes that are novel to science and potentially aphid-specific were identified. Comparison of cDNA data from three aphid lineages identified single nucleotide polymorphisms that can be used as genetic markers and, in some cases, may represent functional differences in the protein products. In particular, non-conservative amino acid substitutions in a highly expressed gut protease may be of adaptive significance for M. persicae feeding on different host plants. The Agilent eArray platform was used to design an M. persicae oligonucleotide microarray representing over 10,000 unique genes. Conclusion New genomic resources have been developed for M. persicae, an agriculturally important insect pest. These include previously unknown sequence data, a collection of expressed genes, molecular markers, and a DNA microarray that can be used to study aphid gene expression. These resources will help elucidate the adaptations that allow M. persicae to develop compatible interactions with its host plants, complementing ongoing work illuminating plant molecular responses to phloem-feeding insects. PMID:18021414
NASA Technical Reports Server (NTRS)
Balcer-Kubiczek, Elizabeth K.; Harrison, George H.; Xu, Jing-Fan; Gutierrez, Peter L.
2002-01-01
The trefoil factors (TFFs) are pleiotropic factors involved in organization and homeostasis of the gastrointestinal tract, estrogen responsiveness, inflammatory disorders, and carcinogenesis. In an earlier study using cDNA array technologies to identify new genes expressed in irradiated cell survivors, we isolated a cDNA clone corresponding to the reported human TFF1 gene (E. K. Balcer-Kubiczek et al., Int. J. Radiat. Biol., 75: 529-541, 1999). To determine whether expression of other TFFs is altered by ionizing radiation, we quantified changes in expression of TFF3 as well as TFF1 in RNA samples obtained from irradiated and control human tumor breast, colon, and gastric tumor cells and examined expression kinetics up to 2 weeks after irradiation. X-ray-induced TFF1 and TFF3 expression profiles were compared with those induced by hydrogen peroxide (H2O2) or 17beta-estradiol (ES). The results revealed that TFF1 and TFF3 mRNA are coinduced by X-irradiation in a subset of the lines, but substantial heterogeneity in their responses was observed in cells derived from a single cell type. TFF1 and TFF3 transcriptional response to X-irradiation differed from that to H2O2 or ES in the timing of their induction as well as tissue-type dependence, i.e., their induction pattern after X-irradiation was late and sustained, whereas their induction by H2O2 or ES was early and transient. TFF1 mRNA, protein production in the cytoplasm, and secretion in the culture supernatant were coordinately regulated after X-irradiation. There was no requirement for TP53 in this induction. These results demonstrate the existence of a novel class of radiation-responsive genes that might be involved in bystander effects.
Solar Cell and Array Technology Development for NASA Solar Electric Propulsion Missions
NASA Technical Reports Server (NTRS)
Piszczor, Michael; McNatt, Jeremiah; Mercer, Carolyn; Kerslake, Tom; Pappa, Richard
2012-01-01
NASA is currently developing advanced solar cell and solar array technologies to support future exploration activities. These advanced photovoltaic technology development efforts are needed to enable very large (multi-hundred kilowatt) power systems that must be compatible with solar electric propulsion (SEP) missions. The technology being developed must address a wide variety of requirements and cover the necessary advances in solar cell, blanket integration, and large solar array structures that are needed for this class of missions. Th is paper will summarize NASA's plans for high power SEP missions, initi al mission studies and power system requirements, plans for advanced photovoltaic technology development, and the status of specific cell and array technology development and testing that have already been conducted.
High-performance, flexible, deployable array development for space applications
NASA Technical Reports Server (NTRS)
Gehling, Russell N.; Armstrong, Joseph H.; Misra, Mohan S.
1994-01-01
Flexible, deployable arrays are an attractive alternative to conventional solar arrays for near-term and future space power applications, particularly due to their potential for high specific power and low storage volume. Combined with low-cost flexible thin-film photovoltaics, these arrays have the potential to become an enabling or an enhancing technology for many missions. In order to expedite the acceptance of thin-film photovoltaics for space applications, however, parallel development of flexible photovoltaics and the corresponding deployable structure is essential. Many innovative technologies must be incorporated in these arrays to ensure a significant performance increase over conventional technologies. For example, innovative mechanisms which employ shape memory alloys for storage latches, deployment mechanisms, and array positioning gimbals can be incorporated into flexible array design with significant improvement in the areas of cost, weight, and reliability. This paper discusses recent activities at Martin Marietta regarding the development of flexible, deployable solar array technology. Particular emphasis is placed on the novel use of shape memory alloys for lightweight deployment elements to improve the overall specific power of the array. Array performance projections with flexible thin-film copper-indium-diselenide (CIS) are presented, and government-sponsored solar array programs recently initiated at Martin Marietta through NASA and Air Force Phillips Laboratory are discussed.
NASA Technical Reports Server (NTRS)
Christensen, Elmer
1985-01-01
The objectives were to develop the flat-plate photovoltaic (PV) array technologies required for large-scale terrestrial use late in the 1980s and in the 1990s; advance crystalline silicon PV technologies; develop the technologies required to convert thin-film PV research results into viable module and array technology; and to stimulate transfer of knowledge of advanced PV materials, solar cells, modules, and arrays to the PV community. Progress reached on attaining these goals, along with future recommendations are discussed.
Daytime soybean transcriptome fluctuations during water deficit stress
USDA-ARS?s Scientific Manuscript database
Since drought can seriously affect plant growth and development and little is known about how the oscillations of gene expression during the drought stress-acclimation response in soybean is affected, we applied Illumina technology to sequence 36 cDNA libraries synthesized from control and drought-s...
NASA Technical Reports Server (NTRS)
Berman, P. A.
1972-01-01
Three major options for wide-scale generation of photovoltaic energy for terrestrial use are considered: (1) rooftop array, (2) solar farm, and (3) satellite station. The rooftop array would use solar cell arrays on the roofs of residential or commercial buildings; the solar farm would consist of large ground-based arrays, probably in arid areas with high insolation; and the satellite station would consist of an orbiting solar array, many square kilometers in area. The technology advancement requirements necessary for each option are discussed, including cost reduction of solar cells and arrays, weight reduction, resistance to environmental factors, reliability, and fabrication capability, including the availability of raw materials. The majority of the technology advancement requirements are applicable to all three options, making possible a flexible basic approach regardless of the options that may eventually be chosen. No conclusions are drawn as to which option is most advantageous, since the feasibility of each option depends on the success achieved in the technology advancement requirements specified.
Yang, XinChao; Li, MengHui; Liu, JianHua; Ji, YiHong; Li, XiangRui; Xu, LiXin; Yan, RuoFeng; Song, XiaoKai
2017-02-16
Eimeria maxima is one of the most prevalent Eimeria species causing avian coccidiosis, and results in huge economic loss to the global poultry industry. Current control strategies, such as anti-coccidial medication and live vaccines have been limited because of their drawbacks. The third generation anticoccidial vaccines including the recombinant vaccines as well as DNA vaccines have been suggested as a promising alternative strategy. To date, only a few protective antigens of E. maxima have been reported. Hence, there is an urgent need to identify novel protective antigens of E. maxima for the development of neotype anticoccidial vaccines. With the aim of identifying novel protective genes of E. maxima, a cDNA expression library of E. maxima sporozoites was constructed using Gateway technology. Subsequently, the cDNA expression library was divided into 15 sub-libraries for cDNA expression library immunization (cDELI) using parasite challenged model in chickens. Protective sub-libraries were selected for the next round of screening until individual protective clones were obtained, which were further sequenced and analyzed. Adopting the Gateway technology, a high-quality entry library was constructed, containing 9.2 × 10 6 clones with an average inserted fragments length of 1.63 kb. The expression library capacity was 2.32 × 10 7 colony-forming units (cfu) with an average inserted fragments length of 1.64 Kb. The expression library was screened using parasite challenged model in chickens. The screening yielded 6 immune protective genes including four novel protective genes of EmJS-1, EmRP, EmHP-1 and EmHP-2, and two known protective genes of EmSAG and EmCKRS. EmJS-1 is the selR domain-containing protein of E. maxima whose function is unknown. EmHP-1 and EmHP-2 are the hypothetical proteins of E. maxima. EmRP and EmSAG are rhomboid-like protein and surface antigen glycoproteins of E. maxima respectively, and involved in invasion of the parasite. Our results provide a cDNA expression library for further screening of T cell stimulating or inhibiting antigens of E. maxima. Moreover, our results provide six candidate protective antigens for developing new vaccines against E. maxima.
Roling, Jonathan A; Bain, Lisa J; Gardea-Torresdey, Jorge; Key, Peter B; Baldwin, William S
2007-06-01
We previously developed a cDNA array for mummichogs (Fundulus heteroclitus), an estuarine minnow, that is targeted for identifying differentially expressed genes from exposure to polycyclic aromatic hydrocarbons and several metals, including chromium. A chromium-contaminated Superfund site at Shipyard Creek in Charleston, South Carolina, USA, is undergoing remediation, providing us a unique opportunity to study the utility of arrays for monitoring the effectiveness of site remediation. Mummichogs were captured in Shipyard Creek in Charleston prior to remediation (2000) and after remediation began (2003 and 2005). Simultaneously, mummichogs were collected from a reference site at the Winyah Bay National Estuarine Research Reserve (NERR) in Georgetown, South Carolina, USA. The hepatic gene expression pattern of fish captured at Shipyard Creek in 2000 showed wide differences from the fish captured at NERR in 2000. Interestingly, as remediation progressed the gene expression pattern of mummichogs captured at Shipyard Creek became increasingly similar to those captured at NERR. The arrays acted as multidimensional biomarkers as the number of differentially expressed genes dropped from 22 in 2000 to four in 2003, and the magnitude of differential expression dropped from 3.2-fold in 2000 to no gene demonstrating a difference over 1.5-fold in 2003. Furthermore, the arrays indicated changes in the bioavailability of chromium caused by hydraulic dredging in the summer of 2005. This research is, to our knowledge, the first report using arrays as biomarkers for a weight-of-evidence hazard assessment and demonstrates that arrays can be used as multidimensional biomarkers to monitor site mitigation because the gene expression profile is associated with chromium bioavailability and body burden.
A Rapid and Improved Method to Generate Recombinant Dengue Virus Vaccine Candidates
Govindarajan, Dhanasekaran; Guan, Liming; Meschino, Steven; Fridman, Arthur; Bagchi, Ansu; Pak, Irene; ter Meulen, Jan; Casimiro, Danilo R.; Bett, Andrew J.
2016-01-01
Dengue is one of the most important mosquito-borne infections accounting for severe morbidity and mortality worldwide. Recently, the tetravalent chimeric live attenuated Dengue vaccine Dengvaxia® was approved for use in several dengue endemic countries. In general, live attenuated vaccines (LAV) are very efficacious and offer long-lasting immunity against virus-induced disease. Rationally designed LAVs can be generated through reverse genetics technology, a method of generating infectious recombinant viruses from full length cDNA contained in bacterial plasmids. In vitro transcribed (IVT) viral RNA from these infectious clones is transfected into susceptible cells to generate recombinant virus. However, the generation of full-length dengue virus cDNA clones can be difficult due to the genetic instability of viral sequences in bacterial plasmids. To circumvent the need for a single plasmid containing a full length cDNA, in vitro ligation of two or three cDNA fragments contained in separate plasmids can be used to generate a full-length dengue viral cDNA template. However, in vitro ligation of multiple fragments often yields low quality template for IVT reactions, resulting in inconsistent low yield RNA. These technical difficulties make recombinant virus recovery less efficient. In this study, we describe a simple, rapid and efficient method of using LONG-PCR to recover recombinant chimeric Yellow fever dengue (CYD) viruses as potential dengue vaccine candidates. Using this method, we were able to efficiently generate several viable recombinant viruses without introducing any artificial mutations into the viral genomes. We believe that the techniques reported here will enable rapid and efficient recovery of recombinant flaviviruses for evaluation as vaccine candidates and, be applicable to the recovery of other RNA viruses. PMID:27008550
A Rapid and Improved Method to Generate Recombinant Dengue Virus Vaccine Candidates.
Govindarajan, Dhanasekaran; Guan, Liming; Meschino, Steven; Fridman, Arthur; Bagchi, Ansu; Pak, Irene; ter Meulen, Jan; Casimiro, Danilo R; Bett, Andrew J
2016-01-01
Dengue is one of the most important mosquito-borne infections accounting for severe morbidity and mortality worldwide. Recently, the tetravalent chimeric live attenuated Dengue vaccine Dengvaxia® was approved for use in several dengue endemic countries. In general, live attenuated vaccines (LAV) are very efficacious and offer long-lasting immunity against virus-induced disease. Rationally designed LAVs can be generated through reverse genetics technology, a method of generating infectious recombinant viruses from full length cDNA contained in bacterial plasmids. In vitro transcribed (IVT) viral RNA from these infectious clones is transfected into susceptible cells to generate recombinant virus. However, the generation of full-length dengue virus cDNA clones can be difficult due to the genetic instability of viral sequences in bacterial plasmids. To circumvent the need for a single plasmid containing a full length cDNA, in vitro ligation of two or three cDNA fragments contained in separate plasmids can be used to generate a full-length dengue viral cDNA template. However, in vitro ligation of multiple fragments often yields low quality template for IVT reactions, resulting in inconsistent low yield RNA. These technical difficulties make recombinant virus recovery less efficient. In this study, we describe a simple, rapid and efficient method of using LONG-PCR to recover recombinant chimeric Yellow fever dengue (CYD) viruses as potential dengue vaccine candidates. Using this method, we were able to efficiently generate several viable recombinant viruses without introducing any artificial mutations into the viral genomes. We believe that the techniques reported here will enable rapid and efficient recovery of recombinant flaviviruses for evaluation as vaccine candidates and, be applicable to the recovery of other RNA viruses.
NASA Astrophysics Data System (ADS)
Wayth, Randall; Sokolowski, Marcin; Booler, Tom; Crosse, Brian; Emrich, David; Grootjans, Robert; Hall, Peter J.; Horsley, Luke; Juswardy, Budi; Kenney, David; Steele, Kim; Sutinjo, Adrian; Tingay, Steven J.; Ung, Daniel; Walker, Mia; Williams, Andrew; Beardsley, A.; Franzen, T. M. O.; Johnston-Hollitt, M.; Kaplan, D. L.; Morales, M. F.; Pallot, D.; Trott, C. M.; Wu, C.
2017-08-01
We describe the design and performance of the Engineering Development Array, which is a low-frequency radio telescope comprising 256 dual-polarisation dipole antennas working as a phased array. The Engineering Development Array was conceived of, developed, and deployed in just 18 months via re-use of Square Kilometre Array precursor technology and expertise, specifically from the Murchison Widefield Array radio telescope. Using drift scans and a model for the sky brightness temperature at low frequencies, we have derived the Engineering Development Array's receiver temperature as a function of frequency. The Engineering Development Array is shown to be sky-noise limited over most of the frequency range measured between 60 and 240 MHz. By using the Engineering Development Array in interferometric mode with the Murchison Widefield Array, we used calibrated visibilities to measure the absolute sensitivity of the array. The measured array sensitivity matches very well with a model based on the array layout and measured receiver temperature. The results demonstrate the practicality and feasibility of using Murchison Widefield Array-style precursor technology for Square Kilometre Array-scale stations. The modular architecture of the Engineering Development Array allows upgrades to the array to be rolled out in a staged approach. Future improvements to the Engineering Development Array include replacing the second stage beamformer with a fully digital system, and to transition to using RF-over-fibre for the signal output from first stage beamformers.
Upregulated Genes In Sporadic, Idiopathic Pulmonary Arterial Hypertension
Edgar, Alasdair J; Chacón, Matilde R; Bishop, Anne E; Yacoub, Magdi H; Polak, Julia M
2006-01-01
Background To elucidate further the pathogenesis of sporadic, idiopathic pulmonary arterial hypertension (IPAH) and identify potential therapeutic avenues, differential gene expression in IPAH was examined by suppression subtractive hybridisation (SSH). Methods Peripheral lung samples were obtained immediately after removal from patients undergoing lung transplant for IPAH without familial disease, and control tissues consisted of similarly sampled pieces of donor lungs not utilised during transplantation. Pools of lung mRNA from IPAH cases containing plexiform lesions and normal donor lungs were used to generate the tester and driver cDNA libraries, respectively. A subtracted IPAH cDNA library was made by SSH. Clones isolated from this subtracted library were examined for up regulated expression in IPAH using dot blot arrays of positive colony PCR products using both pooled cDNA libraries as probes. Clones verified as being upregulated were sequenced. For two genes the increase in expression was verified by northern blotting and data analysed using Student's unpaired two-tailed t-test. Results We present preliminary findings concerning candidate genes upregulated in IPAH. Twenty-seven upregulated genes were identified out of 192 clones examined. Upregulation in individual cases of IPAH was shown by northern blot for tissue inhibitor of metalloproteinase-3 and decorin (P < 0.01) compared with the housekeeping gene glyceraldehydes-3-phosphate dehydrogenase. Conclusion Four of the up regulated genes, magic roundabout, hevin, thrombomodulin and sucrose non-fermenting protein-related kinase-1 are expressed specifically by endothelial cells and one, muscleblind-1, by muscle cells, suggesting that they may be associated with plexiform lesions and hypertrophic arterial wall remodelling, respectively. PMID:16390543
Antunes, Heliton S; Wajnberg, Gabriel; Pinho, Marcos B; Jorge, Natasha Andressa Nogueira; de Moraes, Joyce Luana Melo; Stefanoff, Claudio Gustavo; Herchenhorn, Daniel; Araújo, Carlos M M; Viégas, Celia Maria Pais; Rampini, Mariana P; Dias, Fernando L; de Araujo-Souza, Patricia Savio; Passetti, Fabio; Ferreira, Carlos G
2018-01-01
Oral mucositis is an acute toxicity that occurs in patients submitted to chemoradiotherapy to treat head and neck squamous cell carcinoma. In this study, we evaluated differences in gene expression in the keratinocytes of the oral mucosa of patients treated with photobiomodulation therapy and tried to associate the molecular mechanisms with clinical findings. From June 2009 to December 2010, 27 patients were included in a randomized double-blind pilot study. Buccal smears from 13 patients were obtained at days 1 and 10 of chemoradiotherapy, and overall gene expression of samples from both dates were analyzed by complementary DNA (cDNA) microarray. In addition, samples from other 14 patients were also collected at D1 and D10 of chemoradiotherapy for subsequent validation of cDNA microarray findings by qPCR. The expression array analysis identified 105 upregulated and 60 downregulated genes in our post-treatment samples when compared with controls. Among the upregulated genes with the highest fold change, it was interesting to observe the presence of genes related to keratinocyte differentiation. Among downregulated genes were observed genes related to cytotoxicity and immune response. The results indicate that genes known to be induced during differentiation of human epidermal keratinocytes were upregulated while genes associated with cytotoxicity and immune response were downregulated in the laser group. These results support previous clinical findings indicating that the lower incidence of oral mucositis associated with photobiomodulation therapy might be correlated to the activation of genes involved in keratinocyte differentiation.
Recent results from advanced research on space solar cells at NASA
NASA Technical Reports Server (NTRS)
Flood, Dennis J.
1990-01-01
The NASA program in space photovoltaic research and development encompasses a wide range of emerging options for future space power systems, and includes both cell and array technology development. The long range goals are to develop technology capable of achieving 300 W/kg for planar arrays, and 300 W/sq m for concentrator arrays. InP and GaAs planar and concentrator cell technologies are under investigation for their potential high efficiency and good radiation resistance. The Advanced Photovoltaic Solar Array (APSA) program is a near term effort aimed at demonstrating 130 W/kg beginning of life specific power using thin (62 pm) silicon cells. It is intended to be technology transparent to future high efficiency cells and provides the baseline for development of the 300 W/kg array.
Baker, Valerie A; Harries, Helen M; Waring, Jeff F; Duggan, Colette M; Ni, Hong A; Jolly, Robert A; Yoon, Lawrence W; De Souza, Angus T; Schmid, Judith E; Brown, Roger H; Ulrich, Roger G; Rockett, John C
2004-01-01
Microarrays have the potential to significantly impact our ability to identify toxic hazards by the identification of mechanistically relevant markers of toxicity. To be useful for risk assessment, however, microarray data must be challenged to determine reliability and interlaboratory reproducibility. As part of a series of studies conducted by the International Life Sciences Institute Health and Environmental Science Institute Technical Committee on the Application of Genomics to Mechanism-Based Risk Assessment, the biological response in rats to the hepatotoxin clofibrate was investigated. Animals were treated with high (250 mg/kg/day) or low (25 mg/kg/day) doses for 1, 3, or 7 days in two laboratories. Clinical chemistry parameters were measured, livers removed for histopathological assessment, and gene expression analysis was conducted using cDNA arrays. Expression changes in genes involved in fatty acid metabolism (e.g., acyl-CoA oxidase), cell proliferation (e.g., topoisomerase II-Alpha), and fatty acid oxidation (e.g., cytochrome P450 4A1), consistent with the mechanism of clofibrate hepatotoxicity, were detected. Observed differences in gene expression levels correlated with the level of biological response induced in the two in vivo studies. Generally, there was a high level of concordance between the gene expression profiles generated from pooled and individual RNA samples. Quantitative real-time polymerase chain reaction was used to confirm modulations for a number of peroxisome proliferator marker genes. Though the results indicate some variability in the quantitative nature of the microarray data, this appears due largely to differences in experimental and data analysis procedures used within each laboratory. In summary, this study demonstrates the potential for gene expression profiling to identify toxic hazards by the identification of mechanistically relevant markers of toxicity. PMID:15033592
Wen, Yunfei; Graybill, Whitney S.; Previs, Rebecca A.; Hu, Wei; Ivan, Cristina; Mangala, Lingegowda S.; Zand, Behrouz; Nick, Alpa M.; Jennings, Nicholas B.; Dalton, Heather J.; Sehgal, Vasudha; Ram, Prahlad; Lee, Ju-Seog; Vivas-Mejia, Pablo E.; Coleman, Robert L.; Sood, Anil K.
2014-01-01
Purpose Cancer cells are highly dependent on folate metabolism, making them susceptible to drugs that inhibit folate receptor activities. Targeting overexpressed folate receptor alpha (FRα) in cancer cells offers a therapeutic opportunity. We investigated the functional mechanisms of MORAB-003 (farletuzumab), a humanized monoclonal antibody against FRα, in ovarian cancer models. Experimental Design We first examined FRα expression in an array of human ovarian cancer cell lines and then assessed the in vivo effect of MORAB-003 on tumor growth and progression in several orthotopic mouse models of ovarian cancer derived from these cell lines. Molecular mechanisms of tumor cell death induced by MORAB-003 were investigated by cDNA and protein expression profiling analysis. Mechanistic studies were performed to determine the role of autophagy in MORAB-003–induced cell death. Results MORAB-003 significantly decreased tumor growth in the high-FRα IGROV1 and SKOV3ip1 models but not in the low-FRα A2780 model. MORAB-003 reduced proliferation but had no significant effect on apoptosis. Protein expression and cDNA microarray analyses showed that MORAB-003 regulated an array of autophagy-related genes. It also significantly increased expression of LC3 isoform II and enriched autophagic vacuolization. Blocking autophagy with hydroxychloroquine or bafilomycin A1 reversed the growth inhibition induced by MORAB-003. In add, alteration of FOLR1 gene copy number significantly correlated with shorter disease-free survival in patients with ovarian serous cystadenocarcinoma. Conclusions MORAB-003 displays prominent antitumor activity in ovarian cancer models expressing FRα at high levels. Blockade of folate receptor by MORAB-003 induced sustained autophagy and suppressed cell proliferation. PMID:25416196
Structural Coloration of a Colloidal Amorphous Array is Intensified by Carbon Nanolayers.
Takeoka, Yukikazu; Iwata, Masanori; Seki, Takahiro; Nueangnoraj, Khanin; Nishihara, Hirotomo; Yoshioka, Shinya
2018-04-10
In this study, we introduce the possibility of applying a colloidal amorphous array composed of fine silica particles as a structural-color material to invisible information technology. The appearance of a thick filmlike colloidal amorphous array formed from fine silica particles is considerably influenced by incoherent light scattering across the entire visible region. Therefore, regardless of the diameter of the fine silica particles, the thick colloidal amorphous array exhibits a white color to the naked eye. When carbon is uniformly deposited in the colloidal amorphous array by a pressure-pulsed chemical vapor deposition method, incoherent light scattering in the colloidal amorphous array is suppressed. As a result, coherent light scattering due to the short-range order in the colloidal amorphous array becomes conspicuous and the array exhibits a vivid structural color. As structures, such as letters and pictures, can be drawn using this technology, the colloidal amorphous array as a structural-colored material may also be applicable for invisible information technology.
NASA Technical Reports Server (NTRS)
1987-01-01
The conference provided a forum to assess the progress made, the problems remaining, and the strategy for the future of photovoltaic research. Cell research and technology, space environmental effects, array technology and applications were discussed.
NASA photovoltaic research and technology
NASA Technical Reports Server (NTRS)
Flood, Dennis J.
1988-01-01
NASA photovoltaic R and D efforts address future Agency space mission needs through a comprehensive, integrated program. Activities range from fundamental studies of materials and devices to technology demonstrations of prototype hardware. The program aims to develop and apply an improved understanding of photovoltaic energy conversion devices and systems that will increase the performance, reduce the mass, and extend the lifetime of photovoltaic arrays for use in space. To that end, there are efforts aimed at improving cell efficiency, reducing the effects of space particulate radiation damage (primarily electrons and protons), developing ultralightweight cells, and developing advanced ray component technology for high efficiency concentrator arrays and high performance, ultralightweight arrays. Current goals that have been quantified for the program are to develop cell and array technology capable of achieving 300 watts/kg for future missions for which mass is a critical factor, or 300 watts/sq m for future missions for which array size is a major driver (i.e., Space Station). A third important goal is to develop cell and array technology which will survive the GEO space radiation environment for at least 10 years.
Solar cell array design handbook - The principles and technology of photovoltaic energy conversion
NASA Technical Reports Server (NTRS)
Rauschenbach, H. S.
1980-01-01
Photovoltaic solar cell array design and technology for ground-based and space applications are discussed from the user's point of view. Solar array systems are described, with attention given to array concepts, historical development, applications and performance, and the analysis of array characteristics, circuits, components, performance and reliability is examined. Aspects of solar cell array design considered include the design process, photovoltaic system and detailed array design, and the design of array thermal, radiation shielding and electromagnetic components. Attention is then given to the characteristics and design of the separate components of solar arrays, including the solar cells, optical elements and mechanical elements, and the fabrication, testing, environmental conditions and effects and material properties of arrays and their components are discussed.
Thuwajit, Chanitra; Thuwajit, Peti; Uchida, Kazuhiko; Daorueang, Daoyot; Kaewkes, Sasithorn; Wongkham, Sopit; Miwa, Masanao
2006-06-14
To investigate the mechanism of fibroblast cell proliferation stimulated by the Opisthorchis viverrini excretory/secretory (ES) product. NIH-3T3, mouse fibroblast cells were treated with O. viverrini ES product by non-contact co-cultured with the adult parasites. Total RNA from NIH-3T3 treated and untreated with O. viverrini was extracted, reverse transcribed and hybridized with the mouse 15K complementary DNA (cDNA) array. The result was analyzed by ArrayVision version 5 and GeneSpring version 5 softwares. After normalization, the ratios of gene expression of parasite treated to untreated NIH-3T3 cells of 2-and more-fold upregulated was defined as the differentially expressed genes. The expression levels of the signal transduction genes were validated by semi-quantitative SYBR-based real-time RT-PCR. Among a total of 15,000 genes/ESTs, 239 genes with established cell proliferation-related function were 2 fold-and more-up-regulated by O. viverrini ES product compared to those in cells without exposure to the parasitic product. These genes were classified into groups including energy and metabolism, signal transduction, protein synthesis and translation, matrix and structural protein, transcription control, cell cycle and DNA replication. Moreover, the expressions of serine-threonine kinase receptor, receptor tyrosine kinase and collagen production-related genes were up-regulated by O. viverrini ES product. The expression level of signal transduction genes; pkC, pdgfr alpha, jak 1, eps 8, tgf beta 1i4, strap and h ras measured by real-time RT-PCR confirmed their expression levels to those obtained from cDNA array. However, only the up-regulated expression of pkC, eps 8 and tgfbeta 1i4 which are the downstream signaling molecules of either epidermal growth factor (EGF) or transforming growth factor-beta (TGF-beta) showed statistical significance (P < 0.05). O. viverrini ES product stimulates the significant changes of gene expression in several functional categories and these mainly include transcripts related to cell proliferation. The TGF-beta and EGF signal transduction pathways are indicated as the possible pathways of O. viverrini-driven cell proliferation.
2007-05-01
BOX 25046, FEDERAL CENTER, M.S. 964 DENVER, CO 80225-0046 TECHNOLOGY TYPE/PLATFORM: TMGS MAGNETOMETER/TOWED ARRAY PREPARED BY: U.S. ARMY...GEOLOGICAL SURVEY, TMGS MAGNETOMETER/TOWED ARRAY) 8-CO-160-UXO-021 Karwatka, Michael... TMGS Magnetometer/Towed Array, MEC Unclassified Unclassified Unclassified SAR (Page ii Blank) i ACKNOWLEDGMENTS
Integration of Antibody Array Technology into Drug Discovery and Development.
Huang, Wei; Whittaker, Kelly; Zhang, Huihua; Wu, Jian; Zhu, Si-Wei; Huang, Ruo-Pan
Antibody arrays represent a high-throughput technique that enables the parallel detection of multiple proteins with minimal sample volume requirements. In recent years, antibody arrays have been widely used to identify new biomarkers for disease diagnosis or prognosis. Moreover, many academic research laboratories and commercial biotechnology companies are starting to apply antibody arrays in the field of drug discovery. In this review, some technical aspects of antibody array development and the various platforms currently available will be addressed; however, the main focus will be on the discussion of antibody array technologies and their applications in drug discovery. Aspects of the drug discovery process, including target identification, mechanisms of drug resistance, molecular mechanisms of drug action, drug side effects, and the application in clinical trials and in managing patient care, which have been investigated using antibody arrays in recent literature will be examined and the relevance of this technology in progressing this process will be discussed. Protein profiling with antibody array technology, in addition to other applications, has emerged as a successful, novel approach for drug discovery because of the well-known importance of proteins in cell events and disease development.
DFT algorithms for bit-serial GaAs array processor architectures
NASA Technical Reports Server (NTRS)
Mcmillan, Gary B.
1988-01-01
Systems and Processes Engineering Corporation (SPEC) has developed an innovative array processor architecture for computing Fourier transforms and other commonly used signal processing algorithms. This architecture is designed to extract the highest possible array performance from state-of-the-art GaAs technology. SPEC's architectural design includes a high performance RISC processor implemented in GaAs, along with a Floating Point Coprocessor and a unique Array Communications Coprocessor, also implemented in GaAs technology. Together, these data processors represent the latest in technology, both from an architectural and implementation viewpoint. SPEC has examined numerous algorithms and parallel processing architectures to determine the optimum array processor architecture. SPEC has developed an array processor architecture with integral communications ability to provide maximum node connectivity. The Array Communications Coprocessor embeds communications operations directly in the core of the processor architecture. A Floating Point Coprocessor architecture has been defined that utilizes Bit-Serial arithmetic units, operating at very high frequency, to perform floating point operations. These Bit-Serial devices reduce the device integration level and complexity to a level compatible with state-of-the-art GaAs device technology.
Redundant disk arrays: Reliable, parallel secondary storage. Ph.D. Thesis
NASA Technical Reports Server (NTRS)
Gibson, Garth Alan
1990-01-01
During the past decade, advances in processor and memory technology have given rise to increases in computational performance that far outstrip increases in the performance of secondary storage technology. Coupled with emerging small-disk technology, disk arrays provide the cost, volume, and capacity of current disk subsystems, by leveraging parallelism, many times their performance. Unfortunately, arrays of small disks may have much higher failure rates than the single large disks they replace. Redundant arrays of inexpensive disks (RAID) use simple redundancy schemes to provide high data reliability. The data encoding, performance, and reliability of redundant disk arrays are investigated. Organizing redundant data into a disk array is treated as a coding problem. Among alternatives examined, codes as simple as parity are shown to effectively correct single, self-identifying disk failures.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Preuss, Mary L.; Delmar, Deborah P.; Liu, Bo
Microtubules in interphase plant cells form a cortical array, which is critical for plant cell morphogenesis. Genetic studies imply that the minus end-directed microtubule motor kinesin-like calmodulin-binding protein (KCBP) plays a role in trichome morphogenesis in Arabidopsis. However, it was not clear whether this motor interacted with interphase microtubules. In cotton (Gossypium hirsutum) fibers, cortical microtubules undergo dramatic reorganization during fiber development. In this study, cDNA clones of the cotton KCBP homolog GhKCBP were isolated from a cotton fiber-specific cDNA library. During cotton fiber development from 10 to 21 DPA, the GhKCBP protein level gradually decreases. By immunofluorescence, GhKCBP wasmore » detected as puncta along cortical microtubules in fiber cells of different developmental stages. Thus the results provide evidence that GhKCBP plays a role in interphase cell growth likely by interacting with cortical microtubules. In contrast to fibers, in dividing cells of cotton, GhKCBP localized to the nucleus, the microtubule preprophase band, mitotic spindle, and the phragmoplast. Therefore KCBP likely exerts multiple roles in cell division and cell growth in flowering plants.« less
Advanced Microstrip Antenna Developments : Volume I. Technology Studies for Aircraft Phased Arrays
DOT National Transportation Integrated Search
1981-06-01
Work has continued on improvement of microstrip phased-array antenna technology since the first microstrip phased-array was flight-tested during the FAA 1974-1975 ATS-6 test program. The present development has extended this earlier work in three are...
Model-based variance-stabilizing transformation for Illumina microarray data.
Lin, Simon M; Du, Pan; Huber, Wolfgang; Kibbe, Warren A
2008-02-01
Variance stabilization is a step in the preprocessing of microarray data that can greatly benefit the performance of subsequent statistical modeling and inference. Due to the often limited number of technical replicates for Affymetrix and cDNA arrays, achieving variance stabilization can be difficult. Although the Illumina microarray platform provides a larger number of technical replicates on each array (usually over 30 randomly distributed beads per probe), these replicates have not been leveraged in the current log2 data transformation process. We devised a variance-stabilizing transformation (VST) method that takes advantage of the technical replicates available on an Illumina microarray. We have compared VST with log2 and Variance-stabilizing normalization (VSN) by using the Kruglyak bead-level data (2006) and Barnes titration data (2005). The results of the Kruglyak data suggest that VST stabilizes variances of bead-replicates within an array. The results of the Barnes data show that VST can improve the detection of differentially expressed genes and reduce false-positive identifications. We conclude that although both VST and VSN are built upon the same model of measurement noise, VST stabilizes the variance better and more efficiently for the Illumina platform by leveraging the availability of a larger number of within-array replicates. The algorithms and Supplementary Data are included in the lumi package of Bioconductor, available at: www.bioconductor.org.
Photovoltaic cell and array technology development for future unique NASA missions
NASA Technical Reports Server (NTRS)
Bailey, S.; Curtis, H.; Piszczor, M.; Surampudi, R.; Hamilton, T.; Rapp, D.; Stella, P.; Mardesich, N.; Mondt, J.; Bunker, R.;
2002-01-01
A technology review committee from NASA, the U.S. Department of Energy (DOE), and the Air Force Research Lab, was formed to assess solar cell and array technologies required for future NASA science missions.
Plants, plant pathogens, and microgravity--a deadly trio.
Leach, J E; Ryba-White, M; Sun, Q; Wu, C J; Hilaire, E; Gartner, C; Nedukha, O; Kordyum, E; Keck, M; Leung, H; Guikema, J A
2001-06-01
Plants grown in spaceflight conditions are more susceptible to colonization by plant pathogens. The underlying causes for this enhanced susceptibility are not known. Possibly the formation of structural barriers and the activation of plant defense response components are impaired in spaceflight conditions. Either condition would result from altered gene expression of the plant. Because of the tools available, past studies focused on a few physiological responses or biochemical pathways. With recent advances in genomics research, new tools, including microarray technologies, are available to examine the global impact of growth in the spacecraft on the plant's gene expression profile. In ground-based studies, we have developed cDNA subtraction libraries of rice that are enriched for genes induced during pathogen infection and the defense response. Arrays of these genes are being used to dissect plant defense response pathways in a model system involving wild-type rice plants and lesion mimic mutants. The lesion mimic mutants are ideal experimental tools because they erratically develop defense response-like lesions in the absence of pathogens. The gene expression profiles from these ground-based studies will provide the molecular basis for understanding the biochemical and physiological impacts of spaceflight on plant growth, development and disease defense responses. This, in turn, will allow the development of strategies to manage plant disease for life in the space environment.
Plants, plant pathogens, and microgravity--a deadly trio
NASA Technical Reports Server (NTRS)
Leach, J. E.; Ryba-White, M.; Sun, Q.; Wu, C. J.; Hilaire, E.; Gartner, C.; Nedukha, O.; Kordyum, E.; Keck, M.; Leung, H.;
2001-01-01
Plants grown in spaceflight conditions are more susceptible to colonization by plant pathogens. The underlying causes for this enhanced susceptibility are not known. Possibly the formation of structural barriers and the activation of plant defense response components are impaired in spaceflight conditions. Either condition would result from altered gene expression of the plant. Because of the tools available, past studies focused on a few physiological responses or biochemical pathways. With recent advances in genomics research, new tools, including microarray technologies, are available to examine the global impact of growth in the spacecraft on the plant's gene expression profile. In ground-based studies, we have developed cDNA subtraction libraries of rice that are enriched for genes induced during pathogen infection and the defense response. Arrays of these genes are being used to dissect plant defense response pathways in a model system involving wild-type rice plants and lesion mimic mutants. The lesion mimic mutants are ideal experimental tools because they erratically develop defense response-like lesions in the absence of pathogens. The gene expression profiles from these ground-based studies will provide the molecular basis for understanding the biochemical and physiological impacts of spaceflight on plant growth, development and disease defense responses. This, in turn, will allow the development of strategies to manage plant disease for life in the space environment.
Analysis of large-scale gene expression data.
Sherlock, G
2000-04-01
The advent of cDNA and oligonucleotide microarray technologies has led to a paradigm shift in biological investigation, such that the bottleneck in research is shifting from data generation to data analysis. Hierarchical clustering, divisive clustering, self-organizing maps and k-means clustering have all been recently used to make sense of this mass of data.
Ríos, Gabino; Naranjo, Miguel A; Iglesias, Domingo J; Ruiz-Rivero, Omar; Geraud, Marion; Usach, Antonio; Talón, Manuel
2008-01-01
Background Many fruit-tree species, including relevant Citrus spp varieties exhibit a reproductive biology that impairs breeding and strongly constrains genetic improvements. In citrus, juvenility increases the generation time while sexual sterility, inbreeding depression and self-incompatibility prevent the production of homozygous cultivars. Genomic technology may provide citrus researchers with a new set of tools to address these various restrictions. In this work, we report a valuable genomics-based protocol for the structural analysis of deletion mutations on an heterozygous background. Results Two independent fast neutron mutants of self-incompatible clementine (Citrus clementina Hort. Ex Tan. cv. Clemenules) were the subject of the study. Both mutants, named 39B3 and 39E7, were expected to carry DNA deletions in hemizygous dosage. Array-based Comparative Genomic Hybridization (array-CGH) using a Citrus cDNA microarray allowed the identification of underrepresented genes in these two mutants. Subsequent comparison of citrus deleted genes with annotated plant genomes, especially poplar, made possible to predict the presence of a large deletion in 39B3 of about 700 kb and at least two deletions of approximately 100 and 500 kb in 39E7. The deletion in 39B3 was further characterized by PCR on available Citrus BACs, which helped us to build a partial physical map of the deletion. Among the deleted genes, ClpC-like gene coding for a putative subunit of a multifunctional chloroplastic protease involved in the regulation of chlorophyll b synthesis was directly related to the mutated phenotype since the mutant showed a reduced chlorophyll a/b ratio in green tissues. Conclusion In this work, we report the use of array-CGH for the successful identification of genes included in a hemizygous deletion induced by fast neutron irradiation on Citrus clementina. The study of gene content and order into the 39B3 deletion also led to the unexpected conclusion that microsynteny and local gene colinearity in this species were higher with Populus trichocarpa than with the phylogenetically closer Arabidopsis thaliana. This work corroborates the potential of Citrus genomic resources to assist mutagenesis-based approaches for functional genetics, structural studies and comparative genomics, and hence to facilitate citrus variety improvement. PMID:18691431
[cDNA library construction from panicle meristem of finger millet].
Radchuk, V; Pirko, Ia V; Isaenkov, S V; Emets, A I; Blium, Ia B
2014-01-01
The protocol for production of full-size cDNA using SuperScript Full-Length cDNA Library Construction Kit II (Invitrogen) was tested and high quality cDNA library from meristematic tissue of finger millet panicle (Eleusine coracana (L.) Gaertn) was created. The titer of obtained cDNA library comprised 3.01 x 10(5) CFU/ml in avarage. In average the length of cDNA insertion consisted about 1070 base pairs, the effectivity of cDNA fragment insertions--99.5%. The selective sequencing of cDNA clones from created library was performed. The sequences of cDNA clones were identified with usage of BLAST-search. The results of cDNA library analysis and selective sequencing represents prove good functionality and full length character of inserted cDNA clones. Obtained cDNA library from meristematic tissue of finger millet panicle represents good and valuable source for isolation and identification of key genes regulating metabolism and meristematic development and for mining of new molecular markers to conduct out high quality genetic investigations and molecular breeding as well.
Ka-band MMIC subarray technology program (Ka-Mist)
NASA Technical Reports Server (NTRS)
Pottenger, Warren
1995-01-01
The broad objective of this program was to demonstrate a proof of concept insertion of Monolithic Microwave Integrated Circuit (MMIC) device technology into an innovative (tile architecture) active phased array antenna application supporting advanced EHF communication systems. Ka-band MMIC arrays have long been considered as having high potential for increasing the capability of space, aircraft, and land mobile communication systems in terms of scan performance, data rate, link margin, and flexibility while offering a significant reduction in size, weight, and power consumption. Insertion of MMIC technology into antenna systems, particularly at millimeter wave frequencies using low power and low noise amplifiers in close proximity to the radiating elements, offers a significant improvement in the array transmit efficiency, receive system noise figure, and overall array reliability. Application of active array technology also leads to the use of advanced beamforming techniques that can improve beam agility, diversity, and adaptivity to complex signal environments.
Rapid thermal cycling of new technology solar array blanket coupons
NASA Technical Reports Server (NTRS)
Scheiman, David A.; Smith, Bryan K.; Kurland, Richard M.; Mesch, Hans G.
1990-01-01
NASA Lewis Research Center is conducting thermal cycle testing of a new solar array blanket technologies. These technologies include test coupons for Space Station Freedom (SSF) and the advanced photovoltaic solar array (APSA). The objective of this testing is to demonstrate the durability or operational lifetime of the solar array interconnect design and blanket technology within a low earth orbit (LEO) or geosynchronous earth orbit (GEO) thermal cycling environment. Both the SSF and the APSA array survived all rapid thermal cycling with little or no degradation in peak performance. This testing includes an equivalent of 15 years in LEO for SSF test coupons and 30 years of GEO plus ten years of LEO for the APSA test coupon. It is concluded that both the parallel gap welding of the SSF interconnects and the soldering of the APSA interconnects are adequately designed to handle the thermal stresses of space environment temperature extremes.
NASA Technical Reports Server (NTRS)
Wachholz, James J.; Murphy, David M.
1996-01-01
The SCARLET I (Solar Concentrator Army with Refractive Linear Element Technology) solar array wing was designed and built to demonstrate, in flight, the feasibility of integrating deployable concentrator optics within the design envelope of typical rigid array technology. Innovative mechanism designs were used throughout the array, and a full series of qualification tests were successfully performed in anticipation of a flight on the Multiple Experiment Transporter to Earth Orbit and Return (METEOR) spacecraft. Even though the Conestoga launch vehicle was unable to place the spacecraft in orbit, the program effort was successful in achieving the milestones of analytical and design development functional validation, and flight qualification, thus leading to a future flight evaluation for the SCARLET technology.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wachholz, J.J.; Murphy, D.M.
1996-05-01
The SCARLET I (Solar Concentrator Army with Refractive Linear Element Technology) solar array wing was designed and built to demonstrate, in flight, the feasibility of integrating deployable concentrator optics within the design envelope of typical rigid array technology. Innovative mechanism designs were used throughout the array, and a full series of qualification tests were successfully performed in anticipation of a flight on the Multiple Experiment Transporter to Earth Orbit and Return (METEOR) spacecraft. Even though the Conestoga launch vehicle was unable to place the spacecraft in orbit, the program effort was successful in achieving the milestones of analytical and designmore » development functional validation, and flight qualification, thus leading to a future flight evaluation for the SCARLET technology.« less
Li, Wangzhe; Zhang, Xia; Yao, Jianping
2013-08-26
We report, to the best of our knowledge, the first realization of a multi-wavelength distributed feedback (DFB) semiconductor laser array with an equivalent chirped grating profile based on equivalent chirp technology. All the lasers in the laser array have an identical grating period with an equivalent chirped grating structure, which are realized by nonuniform sampling of the gratings. Different wavelengths are achieved by changing the sampling functions. A multi-wavelength DFB semiconductor laser array is fabricated and the lasing performance is evaluated. The results show that the equivalent chirp technology is an effective solution for monolithic integration of a multi-wavelength laser array with potential for large volume fabrication.
Minimap2: pairwise alignment for nucleotide sequences.
Li, Heng
2018-05-10
Recent advances in sequencing technologies promise ultra-long reads of ∼100 kilo bases (kb) in average, full-length mRNA or cDNA reads in high throughput and genomic contigs over 100 mega bases (Mb) in length. Existing alignment programs are unable or inefficient to process such data at scale, which presses for the development of new alignment algorithms. Minimap2 is a general-purpose alignment program to map DNA or long mRNA sequences against a large reference database. It works with accurate short reads of ≥ 100bp in length, ≥1kb genomic reads at error rate ∼15%, full-length noisy Direct RNA or cDNA reads, and assembly contigs or closely related full chromosomes of hundreds of megabases in length. Minimap2 does split-read alignment, employs concave gap cost for long insertions and deletions (INDELs) and introduces new heuristics to reduce spurious alignments. It is 3-4 times as fast as mainstream short-read mappers at comparable accuracy, and is ≥30 times faster than long-read genomic or cDNA mappers at higher accuracy, surpassing most aligners specialized in one type of alignment. https://github.com/lh3/minimap2. hengli@broadinstitute.org.
Fu, L; Hou, Y L; Ding, X; Du, Y J; Zhu, H Q; Zhang, N; Hou, W R
2016-08-30
The complementary DNA (cDNA) of the giant panda (Ailuropoda melanoleuca) ferritin light polypeptide (FTL) gene was successfully cloned using reverse transcription-polymerase chain reaction technology. We constructed a recombinant expression vector containing FTL cDNA and overexpressed it in Escherichia coli using pET28a plasmids. The expressed protein was then purified by nickel chelate affinity chromatography. The cloned cDNA fragment was 580 bp long and contained an open reading frame of 525 bp. The deduced protein sequence was composed of 175 amino acids and had an estimated molecular weight of 19.90 kDa, with an isoelectric point of 5.53. Topology prediction revealed one N-glycosylation site, two casein kinase II phosphorylation sites, one N-myristoylation site, two protein kinase C phosphorylation sites, and one cell attachment sequence. Alignment indicated that the nucleotide and deduced amino acid sequences are highly conserved across several mammals, including Homo sapiens, Cavia porcellus, Equus caballus, and Felis catus, among others. The FTL gene was readily expressed in E. coli, which gave rise to the accumulation of a polypeptide of the expected size (25.50 kDa, including an N-terminal polyhistidine tag).
Li, You-Zhi; Pan, Ying-Hua; Sun, Chang-Bin; Dong, Hai-Tao; Luo, Xing-Lu; Wang, Zhi-Qiang; Tang, Ji-Liang; Chen, Baoshan
2010-12-01
A cDNA library was constructed from the root tissues of cassava variety Huanan 124 at the root bulking stage. A total of 9,600 cDNA clones from the library were sequenced with single-pass from the 5'-terminus to establish a catalogue of expressed sequence tags (ESTs). Assembly of the resulting EST sequences resulted in 2,878 putative unigenes. Blastn analysis showed that 62.6% of the unigenes matched with known cassava ESTs and the rest had no 'hits' against the cassava database in the integrative PlantGDB database. Blastx analysis showed that 1,715 (59.59%) of the unigenes matched with one or more GenBank protein entries and 1,163 (40.41%) had no 'hits'. A cDNA microarray with 2,878 unigenes was developed and used to analyze gene expression profiling of Huanan 124 at key growth stages including seedling, formation of root system, root bulking, and starch maturity. Array data analysis revealed that (1) the higher ratio of up-regulated ribosome-related genes was accompanied by a high ratio of up-regulated ubiquitin, proteasome-related and protease genes in cassava roots; (2) starch formation and degradation simultaneously occur at the early stages of root development but starch degradation is declined partially due to decrease in UDP-glucose dehydrogenase activity with root maturity; (3) starch may also be synthesized in situ in roots; (4) starch synthesis, translocation, and accumulation are also associated probably with signaling pathways that parallel Wnt, LAM, TCS and ErbB signaling pathways in animals; (5) constitutive expression of stress-responsive genes may be due to the adaptation of cassava to harsh environments during long-term evolution.
A 2x2 W-Band Reference Time-Shifted Phase-Locked Transmitter Array in 65nm CMOS Technology
NASA Technical Reports Server (NTRS)
Tang, Adrian; Virbila, Gabriel; Hsiao, Frank; Wu, Hao; Murphy, David; Mehdi, Imran; Siegel, P. H.; Chang, M-C. Frank
2013-01-01
This paper presents a complete 2x2 phased array transmitter system operating at W-band (90-95 GHz) which employs a PLL reference time-shifting approach instead of using traditional mm-wave phase shifters. PLL reference shifting enables a phased array to be distributed over multiple chips without the need for coherent mm-wave signal distribution between chips. The proposed phased array transmitter system consumes 248 mW per array element when implemented in a 65 nm CMOS technology.
The Advanced Photovoltaic Solar Array (APSA) technology status and performance
NASA Technical Reports Server (NTRS)
Stella, Paul M.; Kurland, Richard M.
1991-01-01
In 1985, the Jet Propulsion Laboratory initiated the Advanced Photovoltaic Solar Array (APSA) program. The program objective is to demonstrate a producible array system by the early 1990s with a specific performance of at least 130 W/kG (beginning-of-life) as an intermediate milestone towards the long range goal of 300 W/kG. The APSA performance represents an approximately four-fold improvement over existing rigid array technology and a doubling of the performance of the first generation NASA/OAST SAFE flexible blanket array of the early 1980s.
Hook, Sharon E.; Skillman, Ann D.; Small, Jack A.; Schultz, Irvin R.
2008-01-01
The increased availability and use of DNA microarrays has allowed the characterization of gene expression patterns associated with exposure to different toxicants. An important question is whether toxicant induced changes in gene expression in fish are sufficiently diverse to allow for identification of specific modes of action and/or specific contaminants. In theory, each class of toxicant may generate a gene expression profile unique to its mode of toxic action. In this study, isogenic (cloned) rainbow trout Oncorhynchus mykiss were exposed to sublethal levels of a series of model toxicants with varying modes of action, including ethynylestradiol (xeno-estrogen), 2,2,4,4′-tetrabromodiphenyl ether (BDE-47, thyroid active), diquat (oxidant stressor), chromium VI, and benzo[a]pyrene (BaP) for a period of 1–3 weeks. An additional experiment measured trenbolone (anabolic steroid; model androgen) induced gene expression changes in sexually mature female trout. Following exposure, fish were euthanized, livers removed and RNA extracted. Fluorescently labeled cDNA were generated and hybridized against a commercially available Atlantic Salmon/Trout array (GRASP project, University of Victoria) spotted with 16,000 cDNA’s. The slides were scanned to measure abundance of a given transcript in each sample relative to controls. Data were analyzed via Genespring (Silicon Genetics) to identify a list of up- and downregulated genes, as well as to determine gene clustering patterns that can be used as “expression signatures”. The results indicate each toxicant exposure caused between 64 and 222 genes to be significantly altered in expression. Most genes exhibiting altered expression responded to only one of the toxicants and relatively few were co-expressed in multiple treatments. For example, BaP and Diquat, both of which exert toxicity via oxidative stress, upregulated 28 of the same genes, of over 100 genes altered by either treatment. Other genes associated with steroidogenesis, p450 and estrogen responsive genes appear to be useful for selectively identifying toxicant mode of action in fish, suggesting a link between gene expression profile and mode of toxicity. Our array results showed good agreement with quantitative real time polymerase chain reaction (qRT PCR), which demonstrates that the arrays are an accurate measure of gene expression. The specificity of the gene expression profile in response to a model toxicant, the link between genes with altered expression and mode of toxic action, and the consistency between array and qRT PCR results all suggest that cDNA microarrays have the potential to screen environmental contaminants for biomarkers and mode of toxic action. PMID:16488489
NASA Astrophysics Data System (ADS)
Wegrzecki, Maciej; Piotrowski, Tadeusz; Bar, Jan; Dobrowolski, Rafał; Klimov, Andrii; Klos, Helena; Marchewka, Michał; Nieprzecki, Marek; Panas, Andrzej; Prokaryn, Piotr; Seredyński, Bartłomiej; Sierakowski, Andrzej; Słysz, Wojciech; Szmigiel, Dariusz; Zaborowski, Michal
2016-12-01
In this paper, the design and technology of two types of 16-element photodiode arrays is described. The arrays were developed by the ITE and are to be used in detection of microdeflection of laser radiation at the Institute of Metrology and Biomedical Engineering in the Faculty of Mechatronics of Warsaw University of Technology. The electrical and photoelectrical parameters of the arrays are presented.
Chang, Xuefeng; Ge, Xiaohong; Li, Hui
2014-01-01
Thermoplastic optical polymers have replaced traditional optical glass for many applications, due to their superior optical performance, mechanical characteristics, low cost, and efficient production process. This paper investigates noncontact microembossing technology used for producing microlens arrays made out of PMMA (polymethyl methacrylate), PS (polyStyrene), and PC (polycarbonate) from a quartz mold, with microhole arrays. An array of planoconvex microlenses are formed because of surface tension caused by applying pressure to the edge of a hole at a certain glass transition temperature. We studied the principle of noncontact microembossing techniques using finite element analysis, in addition to the thermal and mechanical properties of the three polymers. Then, the independently developed hot-embossing equipment was used to fabricate microlens arrays on PMMA, PS, and PC sheets. This is a promising technique for fabricating diverse thermoplastic optical polymer microlens array sheets, with a simple technological process and low production costs. PMID:25162063
Ka-Band MMIC Subarray Technology Program (Ka-Mist)
NASA Technical Reports Server (NTRS)
Pottinger, W.
1995-01-01
Ka-band monolithic microwave integrated circuit (MMIC) arrays have been considered as having high potential for increasing the capability of space, aircraft, and land mobile communication systems in terms of scan performance, data rate, link margin, and flexibility while offering a significant reduction in size, weight, and power consumption. Insertion of MMIC technology into antenna systems, particularly at millimeter wave frequencies using low power and low noise amplifiers in closed proximity to the radiating elements, offers a significant improvement in the array transmit efficiency, receive system noise figure, and overall array reliability. Application of active array technology also leads to the use of advanced beamforming techniques that can improve beam agility, diversity, and adaptivity to complex signal environments. The objective of this program was to demonstrate the technical feasibility of the 'tile' array packaging architecture at EHF via the insertion of 1990 MMIC technology into a functional tile array or subarray module. The means test of this objective was to demonstrate and deliver to NASA a minimum of two 4 x 4 (16 radiating element) subarray modules operating in a transmit mode at 29.6 GHz. Available (1990) MMIC technology was chosen to focus the program effort on the novel interconnect schemes and packaging requirements rather than focusing on MMIC development. Major technical achievements of this program include the successful integration of two 4 x 4 subarray modules into a single antenna array. This 32 element array demonstrates a transmit EIRP of over 300 watts yielding an effective directive power gain in excess of 55 dB at 29.63 GHz. The array has been actively used as the transmit link in airborne/terrestrial mobile communication experiments accomplished via the ACTS satellite launched in August 1993.
Review of infrared scene projector technology-1993
NASA Astrophysics Data System (ADS)
Driggers, Ronald G.; Barnard, Kenneth J.; Burroughs, E. E.; Deep, Raymond G.; Williams, Owen M.
1994-07-01
The importance of testing IR imagers and missile seekers with realistic IR scenes warrants a review of the current technologies used in dynamic infrared scene projection. These technologies include resistive arrays, deformable mirror arrays, mirror membrane devices, liquid crystal light valves, laser writers, laser diode arrays, and CRTs. Other methods include frustrated total internal reflection, thermoelectric devices, galvanic cells, Bly cells, and vanadium dioxide. A description of each technology is presented along with a discussion of their relative benefits and disadvantages. The current state of each methodology is also summarized. Finally, the methods are compared and contrasted in terms of their performance parameters.
Mass spectrometry-based cDNA profiling as a potential tool for human body fluid identification.
Donfack, Joseph; Wiley, Anissa
2015-05-01
Several mRNA markers have been exhaustively evaluated for the identification of human venous blood, saliva, and semen in forensic genetics. As new candidate human body fluid specific markers are discovered, evaluated, and reported in the scientific literature, there is an increasing trend toward determining the ideal markers for cDNA profiling of body fluids of forensic interest. However, it has not been determined which molecular genetics-based technique(s) should be utilized to assess the performance of these markers. In recent years, only a few confirmatory, mRNA/cDNA-based methods have been evaluated for applications in body fluid identification. The most frequently described methods tested to date include quantitative polymerase chain reaction (qPCR) and capillary electrophoresis (CE). However these methods, in particular qPCR, often favor narrow multiplex PCR due to the availability of a limited number of fluorescent dyes/tags. In an attempt to address this technological constraint, this study explored matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) for human body fluid identification via cDNA profiling of venous blood, saliva, and semen. Using cDNA samples at 20pg input phosphoglycerate kinase 1 (PGK1) amounts, body fluid specific markers for the candidate genes were amplified in their corresponding body fluid (i.e., venous blood, saliva, or semen) and absent in the remaining two (100% specificity). The results of this study provide an initial indication that MALDI-TOF MS is a potential fluorescent dye-free alternative method for body fluid identification in forensic casework. However, the inherent issues of low amounts of mRNA, and the damage caused to mRNA by environmental exposures, extraction processes, and storage conditions are important factors that significantly hinder the implementation of cDNA profiling into forensic casework. Published by Elsevier Ireland Ltd.
Complementary DNA libraries: an overview.
Ying, Shao-Yao
2004-07-01
The generation of complete and full-length cDNA libraries for potential functional assays of specific gene sequences is essential for most molecules in biotechnology and biomedical research. The field of cDNA library generation has changed rapidly in the past 10 yr. This review presents an overview of the method available for the basic information of generating cDNA libraries, including the definition of the cDNA library, different kinds of cDNA libraries, difference between methods for cDNA library generation using conventional approaches and a novel strategy, and the quality of cDNA libraries. It is anticipated that the high-quality cDNA libraries so generated would facilitate studies involving genechips and the microarray, differential display, subtractive hybridization, gene cloning, and peptide library generation.
Preparation of fluorescent-dye-labeled cDNA from RNA for microarray hybridization.
Ares, Manuel
2014-01-01
This protocol describes how to prepare fluorescently labeled cDNA for hybridization to microarrays. It consists of two steps: first, a mixture of anchored oligo(dT) and random hexamers is used to prime amine-modified cDNA synthesis by reverse transcriptase using a modified deoxynucleotide with a reactive amine group (aminoallyl-dUTP) and an RNA sample as a template. Second, the cDNA is purified and exchanged into bicarbonate buffer so that the amine groups in the cDNA react with the dye N-hydroxysuccinimide (NHS) esters, covalently joining the dye to the cDNA. The dye-coupled cDNA is purified again, and the amount of dye incorporated per microgram of cDNA is determined.
NASA Technical Reports Server (NTRS)
Spence, Brian; White, Steve; Schmid, Kevin; Douglas Mark
2012-01-01
The Flexible Array Concentrator Technology (FACT) is a lightweight, high-performance reflective concentrator blanket assembly that can be used on flexible solar array blankets. The FACT concentrator replaces every other row of solar cells on a solar array blanket, significantly reducing the cost of the array. The modular design is highly scalable for the array system designer, and exhibits compact stowage, good off-pointing acceptance, and mass/cost savings. The assembly s relatively low concentration ratio, accompanied by a large radiative area, provides for a low cell operating temperature, and eliminates many of the thermal problems inherent in high-concentration-ratio designs. Unlike other reflector technologies, the FACT concentrator modules function on both z-fold and rolled flexible solar array blankets, as well as rigid array systems. Mega-ROSA (Mega Roll-Out Solar Array) is a new, highly modularized and extremely scalable version of ROSA that provides immense power level range capability from 100 kW to several MW in size. Mega-ROSA will enable extremely high-power spacecraft and SEP-powered missions, including space-tug and largescale planetary science and lunar/asteroid exploration missions. Mega-ROSA's inherent broad power scalability is achieved while retaining ROSA s solar array performance metrics and missionenabling features for lightweight, compact stowage volume and affordability. This innovation will enable future ultra-high-power missions through lowcost (25 to 50% cost savings, depending on PV and blanket technology), lightweight, high specific power (greater than 200 to 400 Watts per kilogram BOL (beginning-of-life) at the wing level depending on PV and blanket technology), compact stowage volume (greater than 50 kilowatts per cubic meter for very large arrays), high reliability, platform simplicity (low failure modes), high deployed strength/stiffness when scaled to huge sizes, and high-voltage operation capability. Mega-ROSA is adaptable to all photovoltaic and concentrator flexible blanket technologies, and can readily accommodate standard multijunction and emerging ultra-lightweight IMM (inverted metamorphic) photovoltaic flexible blanket assemblies, as well as ENTECHs Stretched Lens Array (SLA) and DSSs (Deployable Space Systems) FACT, which allows for cost reduction at the array level.
Developing an Inflatable Solar Array
NASA Technical Reports Server (NTRS)
Malone, Patrick K.; Jankowski, Francis J.; Williams, Geoffery T.; Vendura, George J., Jr.
1992-01-01
Viewgraphs describing the development of an inflatable solar array as part of the Inflatable Torus Solar Array Technology (ITSAT) program are presented. Program phases, overall and subsystem designs, and array deployment are addressed.
Microarray expression profiling identifies genes with altered expression in HDL-deficient mice
DOE Office of Scientific and Technical Information (OSTI.GOV)
Callow, Matthew J.; Dudoit, Sandrine; Gong, Elaine L.
2000-05-05
Based on the assumption that severe alterations in the expression of genes known to be involved in HDL metabolism may affect the expression of other genes we screened an array of over 5000 mouse expressed sequence tags (ESTs) for altered gene expression in the livers of two lines of mice with dramatic decreases in HDL plasma concentrations. Labeled cDNA from livers of apolipoprotein AI (apo AI) knockout mice, Scavenger Receptor BI (SR-BI) transgenic mice and control mice were co-hybridized to microarrays. Two-sample t-statistics were used to identify genes with altered expression levels in the knockout or transgenic mice compared withmore » the control mice. In the SR-BI group we found 9 array elements representing at least 5 genes to be significantly altered on the basis of an adjusted p value of less than 0.05. In the apo AI knockout group 8 array elements representing 4 genes were altered compared with the control group (p < 0.05). Several of the genes identified in the SR-BI transgenic suggest altered sterol metabolism and oxidative processes. These studies illustrate the use of multiple-testing methods for the identification of genes with altered expression in replicated microarray experiments of apo AI knockout and SR-BI transgenic mice.« less
NASA Technical Reports Server (NTRS)
Mikellides, I. G.; Jongeward, G. A.; Schneider, T.; Carruth, M. R.; Peterson, T.; Kerslake, T. W.; Snyder, D.; Ferguson, D.; Hoskins, A.
2004-01-01
A three-year program to develop a Direct Drive Hall-Effect Thruster system (D2HET) begun in 2001 as part of the NASA Advanced Cross-Enterprise Technology Development initiative. The system, which is expected to reduce significantly the power processing, complexity, weight, and cost over conventional low-voltage systems, will employ solar arrays that operate at voltages higher than (or equal to) 300 V. The lessons learned from the development of the technology also promise to become a stepping-stone for the production of the next generation of power systems employing high voltage solar arrays. This paper summarizes the results from experiments conducted mainly at the NASA Marshal Space Flight Center with two main solar array technologies. The experiments focused on electron collection and arcing studies, when the solar cells operated at high voltages. The tests utilized small coupons representative of each solar array technology. A hollow cathode was used to emulate parts of the induced environment on the solar arrays, mostly the low-energy charge-exchange plasma (1012-1013 m-3 and 0.5-1 eV). Results and conclusions from modeling of electron collection are also summarized. The observations from the total effort are used to propose a preliminary, new solar array design for 2 kW and 30-40 kW class, deep space missions that may employ a single or a cluster of Hall- Effect thrusters.
Integrated residential photovoltaic array development
NASA Astrophysics Data System (ADS)
Shepard, N. F., Jr.
1981-12-01
An advanced, universally-mountable, integrated residential photovoltaic array concept was defined based upon an in-depth formulation and evaluation of three candidate approaches which were synthesized from existing or proposed residential array concepts. The impact of module circuitry and process sequence is considered and technology gaps and performance drivers associated with residential photovoltaic array concepts are identified. The actual learning experience gained from the comparison of the problem areas of the hexagonal shingle design with the rectangular module design led to what is considered an advanced array concept. Building the laboratory mockup provided actual experience and the opportunity to uncover additional technology gaps.
Coherent Detector Arrays for Continuum and Spectral Line Applications
NASA Technical Reports Server (NTRS)
Gaier, Todd C.
2006-01-01
This viewgraph presentation reviews the requirements for improved coherent detector arrays for use in continuum and spectral line applications. With detectors approaching fundamental limits, large arrays offer the only path to sensitivity improvement. Monolithic Microwave Integrated Circuit (MMIC) technology offers a straightforward path to massive focal plane millimeter wave arrays: The technology will readily support continuum imagers, polarimeters and spectral line receivers from 30-110 GHz. Science programs, particularly large field blind surveys will benefit from simultaneous observations of hundreds or thousands of pixels 1000 element array is competitive with a cost less than $2M.
NASA Astrophysics Data System (ADS)
Paulsen, Lee; Hoffmann, Ted; Fulton, Caleb; Yeary, Mark; Saunders, Austin; Thompson, Dan; Chen, Bill; Guo, Alex; Murmann, Boris
2015-05-01
Phased array systems offer numerous advantages to the modern warfighter in multiple application spaces, including Radar, Electronic Warfare, Signals Intelligence, and Communications. However, a lack of commonality in the underlying technology base for DoD Phased Arrays has led to static systems with long development cycles, slow technology refreshes in response to emerging threats, and expensive, application-specific sub-components. The IMPACT module (Integrated Multi-use Phased Array Common Tile) is a multi-channel, reconfigurable, cost-effective beamformer that provides a common building block for multiple, disparate array applications.
Integrated residential photovoltaic array development
NASA Technical Reports Server (NTRS)
Shepard, N. F., Jr.
1981-01-01
An advanced, universally-mountable, integrated residential photovoltaic array concept was defined based upon an in-depth formulation and evaluation of three candidate approaches which were synthesized from existing or proposed residential array concepts. The impact of module circuitry and process sequence is considered and technology gaps and performance drivers associated with residential photovoltaic array concepts are identified. The actual learning experience gained from the comparison of the problem areas of the hexagonal shingle design with the rectangular module design led to what is considered an advanced array concept. Building the laboratory mockup provided actual experience and the opportunity to uncover additional technology gaps.
Soares, Marcelo Bento; Bonaldo, Maria de Fatima
1998-01-01
This invention provides a method to normalize a cDNA library comprising: (a) constructing a directionally cloned library containing cDNA inserts wherein the insert is capable of being amplified by polymerase chain reaction; (b) converting a double-stranded cDNA library into single-stranded DNA circles; (c) generating single-stranded nucleic acid molecules complementary to the single-stranded DNA circles converted in step (b) by polymerase chain reaction with appropriate primers; (d) hybridizing the single-stranded DNA circles converted in step (b) with the complementary single-stranded nucleic acid molecules generated in step (c) to produce partial duplexes to an appropriate Cot; and (e) separating the unhybridized single-stranded DNA circles from the hybridized DNA circles, thereby generating a normalized cDNA library. This invention also provides a method to normalize a cDNA library wherein the generating of single-stranded nucleic acid molecules complementary to the single-stranded DNA circles converted in step (b) is by excising cDNA inserts from the double-stranded cDNA library; purifying the cDNA inserts from cloning vectors; and digesting the cDNA inserts with an exonuclease. This invention further provides a method to construct a subtractive cDNA library following the steps described above. This invention further provides normalized and/or subtractive cDNA libraries generated by the above methods.
Soares, M.B.; Fatima Bonaldo, M. de
1998-12-08
This invention provides a method to normalize a cDNA library comprising: (a) constructing a directionally cloned library containing cDNA inserts wherein the insert is capable of being amplified by polymerase chain reaction; (b) converting a double-stranded cDNA library into single-stranded DNA circles; (c) generating single-stranded nucleic acid molecules complementary to the single-stranded DNA circles converted in step (b) by polymerase chain reaction with appropriate primers; (d) hybridizing the single-stranded DNA circles converted in step (b) with the complementary single-stranded nucleic acid molecules generated in step (c) to produce partial duplexes to an appropriate Cot; and (e) separating the unhybridized single-stranded DNA circles from the hybridized DNA circles, thereby generating a normalized cDNA library. This invention also provides a method to normalize a cDNA library wherein the generating of single-stranded nucleic acid molecules complementary to the single-stranded DNA circles converted in step (b) is by excising cDNA inserts from the double-stranded cDNA library; purifying the cDNA inserts from cloning vectors; and digesting the cDNA inserts with an exonuclease. This invention further provides a method to construct a subtractive cDNA library following the steps described above. This invention further provides normalized and/or subtractive cDNA libraries generated by the above methods. 25 figs.
NASA Technical Reports Server (NTRS)
1985-01-01
The seventh NASA Conference on Space Photovoltaic Research and Technology was held at NASA Lewis Research Center, Cleveland, Ohio, from 30 April until 2 May 1985. Its purpose was to assess the progress made, the problems remaining, and future strategy for space photovoltaic research. Particular emphasis was placed on high efficiency, space environment, and array technology.
Parallel gene analysis with allele-specific padlock probes and tag microarrays
Banér, Johan; Isaksson, Anders; Waldenström, Erik; Jarvius, Jonas; Landegren, Ulf; Nilsson, Mats
2003-01-01
Parallel, highly specific analysis methods are required to take advantage of the extensive information about DNA sequence variation and of expressed sequences. We present a scalable laboratory technique suitable to analyze numerous target sequences in multiplexed assays. Sets of padlock probes were applied to analyze single nucleotide variation directly in total genomic DNA or cDNA for parallel genotyping or gene expression analysis. All reacted probes were then co-amplified and identified by hybridization to a standard tag oligonucleotide array. The technique was illustrated by analyzing normal and pathogenic variation within the Wilson disease-related ATP7B gene, both at the level of DNA and RNA, using allele-specific padlock probes. PMID:12930977
DOE Office of Scientific and Technical Information (OSTI.GOV)
Farahani, Poupak; Chiu, Sally; Bowlus, Christopher L.
Obesity is a complex disease. To date, over 100 chromosomal loci for body weight, body fat, regional white adipose tissue weight, and other obesity-related traits have been identified in humans and in animal models. For most loci, the underlying genes are not yet identified; some of these chromosomal loci will be alleles of known obesity genes, whereas many will represent alleles of unknown genes. Microarray analysis allows simultaneous multiple gene and pathway discovery. cDNA and oligonucleotide arrays are commonly used to identify differentially expressed genes by surveys of large numbers of known and unnamed genes. Two papers previously identified genesmore » differentially expressed in adipose tissue of mouse models of obesity and diabetes by analysis of hybridization to Affymetrix oligonucleotide chips.« less
Proceedings of the Third Infrared Detector Technology Workshop
NASA Technical Reports Server (NTRS)
Mccreight, Craig R. (Compiler)
1989-01-01
This volume consists of 37 papers which summarize results presented at the Third Infrared Detector Technology Workshop, held February 7-9, 1989, at Ames Research Center. The workshop focused on infrared (IR) detector, detector array, and cryogenic electronic technologies relevant to low-background space astronomy. Papers on discrete IR detectors, cryogenic readouts, extrinsic and intrinsic IR arrays, and recent results from ground-based observations with integrated arrays were given. Recent developments in the second-generation Hubble Space Telescope (HST) infrared spectrometer and in detectors and arrays for the European Space Agency's Infrared Space Observatory (ISO) are also included, as are status reports on the Space Infrared Telescope Facility (SIRTF) and the Stratospheric Observatory for Infrared Astronomy (SOFIA) projects.
Phased Arrays 1985 Symposium - Proceedings
1985-08-01
have served the logic industry well, and appropriate versions can do the same for micruwdve drid millimeter * wave technology, An aspect of phased...continuing revolutions of the logic industry and the microwave monolithic integrated circuit community are bringing relevant technology closer to the array...monolithic phased array antennas, and discuss their relative advantages and disadvantages . Considerations such as bandwidth, maxianiru scan range, feed
Proceedings of the Second Infrared Detector Technology Workshop
NASA Technical Reports Server (NTRS)
Mccreight, C. R. (Compiler)
1986-01-01
The workshop focused on infrared detector, detector array, and cryogenic electronic technologies relevant to low-background space astronomy. Papers are organized into the following categories: discrete infrared detectors and readout electronics; advanced bolometers; intrinsic integrated infrared arrays; and extrinsic integrated infrared arrays. Status reports on the Space Infrared Telescope Facility (SIRTF) and Infrared Space Observatory (ISO) programs are also included.
Microelectronic electroporation array
NASA Astrophysics Data System (ADS)
Johnson, Lee J.; Shaffer, Kara J.; Skeath, Perry; Perkins, Frank K.; Pancrazio, Joseph; Scribner, Dean
2004-06-01
Gene Array technology has allowed for the study of gene binding by creating thousands of potential binding sites on a single device. A limitation of the current technology is that the effects of the gene and the gene-derived proteins cannot be studied in situ the same way, thousand site cell arrays are not readily available. We propose a new device structure to study the effects of gene modification on cells. This new array technology uses electroporation to target specific areas within a cell culture for transfection of genes. Electroporation arrays will allow high throughput analysis of gene effects on a given cell's response to a stress or a genes ability to restore normal cell function in disease modeling cells. Fluorescent imaging of dye labeled indicator molecules or cell viability will provide results indicating the most effective genes. The electroporation array consists of a microelectronic circuit, ancillary electronics, protecting electrode surface for cell culturing and a perfusion system for gene or drug delivery. The advantages of the current device are that there are 3200 sites for electroporation, all or any subsets of the electrodes can be activated. The cells are held in place by the electrode material. This technology could also be applied to high throughput screening of cell impermeant drugs.
Elevation of Autoantibody in Patients with Ischemic Stroke.
Yoshida, Yoichi; Hiwasa, Takaki; Machida, Toshio; Kobayashi, Eiichi; Mine, Seiichiro; Matsushima, Jun; Takiguchi, Masaki; Iwadate, Yasuo
2018-05-31
Recent clinical research has revealed a significant correlation between atherosclerosis, one of the primary etiologies of ischemic stroke, and the immune system. Assuming that "disease-specific autoantibodies are produced in the sera of patients with ischemic stroke," we investigated multiple arteriosclerosis-related antibodies using the serological identification of antigens by recombinant cDNA expression cloning (SEREX), an established method for identifying antigenic proteins. We either screened a human aortic endothelial cell cDNA library or conducted protein array screening using the sera from patients with ischemic stroke, such as carotid artery stenosis or transient ischemic attack (TIA). Next, we measured serum antibody levels using amplified luminescent proximity homogeneous assay-linked immunosorbent assay (AlphaLISA) in patient/healthy donor (HD) cohorts and identified several antigens, the antibody levels of which were significantly higher in patients with ischemic stroke than in HDs. This review introduced the method of identifying antigens by the SEREX and protein microarray and summarized antigenic proteins. In particular, it focused on anti-replication protein A2 antibody and anti-programmed cell death 11 antibody, which are significantly related to atherosclerotic plaque and ischemic brain tissue, respectively, and proposed the mechanism of elevated autoantibody levels against them. Furthermore, this review suggests a possibility of clinical application as an atherosclerotic disease diagnostic marker for TIA or cerebral infarction.
Li, He; Li, Xin; Smerin, Stanley E; Zhang, Lei; Jia, Min; Xing, Guoqiang; Su, Yan A; Wen, Jillian; Benedek, David; Ursano, Robert
2014-01-01
The metabolic mechanisms underlying the development of exaggerated fear in post-traumatic stress disorder (PTSD) are not well defined. In the present study, alteration in the expression of genes associated with mitochondrial function in the amygdala of an animal model of PTSD was determined. Amygdala tissue samples were excised from 10 non-stressed control rats and 10 stressed rats, 14 days post-stress treatment. Total RNA was isolated, cDNA was synthesized, and gene expression levels were determined using a cDNA microarray. During the development of the exaggerated fear associated with PTSD, 48 genes were found to be significantly upregulated and 37 were significantly downregulated in the amygdala complex based on stringent criteria (p < 0.01). Ingenuity pathway analysis revealed up- or downregulation in the amygdala complex of four signaling networks - one associated with inflammatory and apoptotic pathways, one with immune mediators and metabolism, one with transcriptional factors, and one with chromatin remodeling. Thus, informatics of a neuronal gene array allowed us to determine the expression profile of mitochondrial genes in the amygdala complex of an animal model of PTSD. The result is a further understanding of the metabolic and neuronal signaling mechanisms associated with delayed and exaggerated fear.
Time-dependent Translational Response of E. coli to Excess Zn(II)
Easton, J. Allen; Thompson, Peter; Crowder, Michael W.
2006-01-01
Zinc homeostasis is not well understood beyond methods of import and export. In order to better understand zinc homeostasis in Escherichia coli by identifying Zn(ii)-responsive proteins, a proteomic approach was taken. Through the use of two-dimensional gel electrophoresis, we were able to show that the levels of OmpF, AspC, YcdO, Eno, and CysE increased after 30 min of Zn(ii) stress, while the levels of Tig, TufA, SelA, and LeuC decreased relative to non-stressed controls. After 4 h of Zn(ii) stress, the levels of three proteins (DnaK, YeaU, and Mdh) were found to be up-regulated, while the levels of seven amino acid importers (HisJ, ArgT, LivJ, DppA, OppA, RbsB, and GinH) were found to be decreased. None of these proteins had been reported to be up- or down-regulated in any previously published cDNA microarray experiments. This result raises questions about the validity of cDNA arrays when they are used to make assumptions concerning protein levels within bacterial cells. These data also suggest that time is a factor when characterizing how the E. coli proteome responds to Zn(ii) stress. PMID:17122063
USDA-ARS?s Scientific Manuscript database
Codon bias deoptimization has been previously used to successfully attenuate human pathogens including polio, respiratory syncytial and influenza viruses. We have applied a similar technology to deoptimize the capsid coding region (P1 region) of the cDNA infectious clone of foot-and-mouth disease vi...
Photovoltaic options for solar electric propulsion
NASA Technical Reports Server (NTRS)
Stella, Paul M.; Flood, Dennis J.
1990-01-01
This paper discusses both state-of-the-art and advanced development cell and array technology. Present technology includes rigid, roll-out, and foldout flexible substrate designs, with silicon and GaAs solar cells. The use of concentrator array systems is discussed based on both DOD efforts and NASA work. The benefits of advanced lightweight array technology, for both near term and far term utilization, and of advanced high efficiency thin radiation resistant cells is examined. This includes gallium arsenide/germanium, indium phosphide, and thin film devices such as copper indium disclenide.
Integrated detector array technology for infrared astronomy
NASA Technical Reports Server (NTRS)
Mccreight, c. R.; Goebel, J. H.; Mckelvey, M. E.; Stafford, P. S.; Lee, J. H.
1984-01-01
The status of laboratory and telescope tests of integrated infrared detector array technology for astronomical applications is described. The devices tested represent a number of extrinsic and intrinsic detector materials and various multiplexer designs. Infrared arrays have now been used in successful astronomical applications. These have shown that device sensitivities can be comparable to those of discrete detector systems and excellent astronomical imagery can be produced.
Integrating Residential Photovoltaics With Power Lines
NASA Technical Reports Server (NTRS)
Borden, C. S.
1985-01-01
Report finds rooftop solar-cell arrays feed excess power to electric-utility grid for fee are potentially attractive large-scale application of photovoltaic technology. Presents assessment of breakeven costs of these arrays under variety of technological and economic assumptions.
NASA Astrophysics Data System (ADS)
Carson, John C.
1990-11-01
Various papers on materials, devices, techniques, and applications for X-plane focal plane array technology are presented. Individual topics addressed include: application of Z-plane technology to the remote sensing of the earth from GEO, applications of smart neuromorphic focal planes, image-processing of Z-plane technology, neural network Z-plane implementation with very high interconnection rates, using a small IR surveillance satellite for tactical applications, establishing requirements for homing applications, Z-plane technology. Also discussed are: on-array spike suppression signal processing, algorithms for on-focal-plane gamma circumvention and time-delay integration, current HYMOSS Z-technology, packaging of electrons for on- and off-FPA signal processing, space/performance qualification of tape automated bonded devices, automation in tape automated bonding, high-speed/high-volume radiometric testing of Z-technology focal planes, 128-layer HYMOSS-module fabrication issues, automation of IRFPA production processes.
JPRS Report, Science & Technology, China, High-Performance Computer Systems
1992-10-28
microprocessor array The microprocessor array in the AP85 system is com- posed of 16 completely identical array element micro - processors . Each array element...microprocessors and capable of host machine reading and writing. The memory capacity of the array element micro - processors as a whole can be expanded...transmission functions to carry out data transmission from array element micro - processor to array element microprocessor, from array element
Low-background detector arrays for infrared astronomy
NASA Technical Reports Server (NTRS)
Mccreight, C. R.; Estrada, J. A.; Goebel, J. H.; Mckelvey, M. E.; Mckibbin, D. D.; Mcmurray, R. E., Jr.; Weber, T. T.
1989-01-01
The status of a program which develops and characterizes integrated infrared (IR) detector array technology for space astronomical applications is described. The devices under development include intrinsic, extrinsic silicon, and extrinsic germanium detectors, coupled to silicon readout electronics. Low-background laboratory test results include measurements of responsivity, noise, dark current, temporal response, and the effects of gamma-radiation. In addition, successful astronomical imagery has been obtained on some arrays from this program. These two aspects of the development combine to demonstrate the strong potential for integrated array technology for IR space astronomy.
Optoelectronic Infrastructure for Radio Frequency and Optical Phased Arrays
NASA Technical Reports Server (NTRS)
Cai, Jianhong
2015-01-01
Optoelectronic integrated circuits offer radiation-hardened solutions for satellite systems in addition to improved size, weight, power, and bandwidth characteristics. ODIS, Inc., has developed optoelectronic integrated circuit technology for sensing and data transfer in phased arrays. The technology applies integrated components (lasers, amplifiers, modulators, detectors, and optical waveguide switches) to a radio frequency (RF) array with true time delay for beamsteering. Optical beamsteering is achieved by controlling the current in a two-dimensional (2D) array. In this project, ODIS integrated key components to produce common RF-optical aperture operation.
NASA Technical Reports Server (NTRS)
Ando, K.
1982-01-01
A substantial technology base of solid state pushbroom sensors exists and is in the process of further evolution at both GSFC and JPL. Technologies being developed relate to short wave infrared (SWIR) detector arrays; HgCdTe hybrid detector arrays; InSb linear and area arrays; passive coolers; spectral beam splitters; the deposition of spectral filters on detector arrays; and the functional design of the shuttle/space platform imaging spectrometer (SIS) system. Spatial and spectral characteristics of field, aircraft and space multispectral sensors are summaried. The status, field of view, and resolution of foreign land observing systems are included.
Study of Power Options for Jupiter and Outer Planet Missions
NASA Technical Reports Server (NTRS)
Landis, Geoffrey A.; Fincannon, James
2015-01-01
Power for missions to Jupiter and beyond presents a challenging goal for photovoltaic power systems, but NASA missions including Juno and the upcoming Europa Clipper mission have shown that it is possible to operate solar arrays at Jupiter. This work analyzes photovoltaic technologies for use in Jupiter and outer planet missions, including both conventional arrays, as well as analyzing the advantages of advanced solar cells, concentrator arrays, and thin film technologies. Index Terms - space exploration, spacecraft solar arrays, solar electric propulsion, photovoltaic cells, concentrator, Fresnel lens, Jupiter missions, outer planets.
A SNP resource for Douglas-fir: de novo transcriptome assembly and SNP detection and validation.
Howe, Glenn T; Yu, Jianbin; Knaus, Brian; Cronn, Richard; Kolpak, Scott; Dolan, Peter; Lorenz, W Walter; Dean, Jeffrey F D
2013-02-28
Douglas-fir (Pseudotsuga menziesii), one of the most economically and ecologically important tree species in the world, also has one of the largest tree breeding programs. Although the coastal and interior varieties of Douglas-fir (vars. menziesii and glauca) are native to North America, the coastal variety is also widely planted for timber production in Europe, New Zealand, Australia, and Chile. Our main goal was to develop a SNP resource large enough to facilitate genomic selection in Douglas-fir breeding programs. To accomplish this, we developed a 454-based reference transcriptome for coastal Douglas-fir, annotated and evaluated the quality of the reference, identified putative SNPs, and then validated a sample of those SNPs using the Illumina Infinium genotyping platform. We assembled a reference transcriptome consisting of 25,002 isogroups (unique gene models) and 102,623 singletons from 2.76 million 454 and Sanger cDNA sequences from coastal Douglas-fir. We identified 278,979 unique SNPs by mapping the 454 and Sanger sequences to the reference, and by mapping four datasets of Illumina cDNA sequences from multiple seed sources, genotypes, and tissues. The Illumina datasets represented coastal Douglas-fir (64.00 and 13.41 million reads), interior Douglas-fir (80.45 million reads), and a Yakima population similar to interior Douglas-fir (8.99 million reads). We assayed 8067 SNPs on 260 trees using an Illumina Infinium SNP genotyping array. Of these SNPs, 5847 (72.5%) were called successfully and were polymorphic. Based on our validation efficiency, our SNP database may contain as many as ~200,000 true SNPs, and as many as ~69,000 SNPs that could be genotyped at ~20,000 gene loci using an Infinium II array-more SNPs than are needed to use genomic selection in tree breeding programs. Ultimately, these genomic resources will enhance Douglas-fir breeding and allow us to better understand landscape-scale patterns of genetic variation and potential responses to climate change.
DNA ARRAYS: TECHNOLOGY, OPTIONS AND TOXOCOLOGICAL APPLICATIONS
DNA arrays: technology, options and toxicological applications.
Rockett JC, Dix DJ.
Reproductive Toxicology Division, National Health and Environmental Effects Research Laboratory, US Environmental Protection Agency, NC 27711, USA. rockett.john@epa.gov
The hu...
Sass, Gabriele; Shembade, Noula D.; Tiegs, Gisa
2004-01-01
TNF (tumour necrosis factor α) induces tolerance towards itself in experimental liver injury. Tolerance induction has been shown to be dependent on TNFR1 (TNF receptor 1) signalling, but mechanisms and mediators of TNF-induced hepatic tolerance are unknown. We investigated the TNF-inducible gene-expression profile in livers of TNFR2−/− mice, using cDNA array technology. We found that, out of 793 investigated genes involved in inflammation, cell cycle and signal transduction, 282 were expressed in the mouse liver in response to TNF via TNFR1. Among those, expression of 78 genes was induced, while expression of 60 genes was reduced. We investigated further the cellular expression of the 27 most prominently induced genes, and found that 20 of these genes were up-regulated directly in parenchymal liver cells, representing potentially protective proteins and possible mediators of TNF tolerance. In vitro experiments revealed that overexpression of SOCS1 (silencer of cytokine signalling 1), a member of the SOCS family of proteins, as well as of HO-1 (haem oxygenase-1), but not of SOCS2 or SOCS3, protected isolated primary mouse hepatocytes from TNF-induced apoptosis. The identification of protective genes in hepatocytes is the prerequisite for future development of gene therapies for immune-mediated liver diseases. PMID:15554901
LSSA (Low-cost Silicon Solar Array) project
NASA Technical Reports Server (NTRS)
1976-01-01
Methods are explored for economically generating electrical power to meet future requirements. The Low-Cost Silicon Solar Array Project (LSSA) was established to reduce the price of solar arrays by improving manufacturing technology, adapting mass production techniques, and promoting user acceptance. The new manufacturing technology includes the consideration of new silicon refinement processes, silicon sheet growth techniques, encapsulants, and automated assembly production being developed under contract by industries and universities.
NASA Technical Reports Server (NTRS)
Woods, Lawrence M.; Kalla, Ajay; Gonzalez, Damian; Ribelin, Rosine
2005-01-01
Future spacecraft and high-altitude airship (HAA) technologies will require high array specific power (W/kg), which can be met using thin-film photovoltaics (PV) on lightweight and flexible substrates. It has been calculated that the thin-film array technology, including the array support structure, begins to exceed the specific power of crystalline multi-junction arrays when the thin-film device efficiencies begin to exceed 12%. Thin-film PV devices have other advantages in that they are more easily integrated into HAA s, and are projected to be much less costly than their crystalline PV counterparts. Furthermore, it is likely that only thin-film array technology will be able to meet device specific power requirements exceeding 1 kW/kg (photovoltaic and integrated substrate/blanket mass only). Of the various thin-film technologies, single junction and radiation resistant CuInSe2 (CIS) and associated alloys with gallium, aluminum and sulfur have achieved the highest levels of thin-film device performance, with the best efficiency, reaching 19.2% under AM1.5 illumination conditions and on thick glass substrates.(3) Thus, it is anticipated that single- and tandem-junction devices with flexible substrates and based on CIS and related alloys could achieve the highest levels of thin-film space and HAA solar array performance.
Analysis of mismatch and shading effects in a photovoltaic array using different technologies
NASA Astrophysics Data System (ADS)
Guerrero, J.; Muñoz, Y.; Ibáñez, F.; Ospino, A.
2014-06-01
In this paper, we analyze the performance of a photovoltaic array implemented in the Universidad Politécnica de Valencia which consists of modules of different technologies and power, connected in series, in order to quantify the energy losses due to mismatch and the effect of the shadows. To do this, the performance of the modules was measured in operation under ambient conditions with field measurement equipment (AMPROBE Solar Analyzer, Solar - 4000), which allows the extrapolation of measures to standard conditions STC. For the data validation, measures under controlled conditions were taken to some modules in the flash test laboratory of the Institute of Energy Technology ITE of Valencia in Spain. Subsequently the array curves measured were validated with a photovoltaic array model developed in MATLAB-Simulink for the same conditions and technologies. The results of this particular array are lost up to 20% of the energy supplied due to the modules mismatch. The study shows the curves and the energy loss due to shadows modules. This result opens scenarios for conceivable modifications to the PV field configurations today, chosen during the design stage and unchangeable during the operating stage; and gives greater importance to the energy loss by mismatch in the PV array.
Thormar, Hans G; Gudmundsson, Bjarki; Eiriksdottir, Freyja; Kil, Siyoen; Gunnarsson, Gudmundur H; Magnusson, Magnus Karl; Hsu, Jason C; Jonsson, Jon J
2013-04-01
The causes of imprecision in microarray expression analysis are poorly understood, limiting the use of this technology in molecular diagnostics. Two-dimensional strandness-dependent electrophoresis (2D-SDE) separates nucleic acid molecules on the basis of length and strandness, i.e., double-stranded DNA (dsDNA), single-stranded DNA (ssDNA), and RNA·DNA hybrids. We used 2D-SDE to measure the efficiency of cDNA synthesis and its importance for the imprecision of an in vitro transcription-based microarray expression analysis. The relative amount of double-stranded cDNA formed in replicate experiments that used the same RNA sample template was highly variable, ranging between 0% and 72% of the total DNA. Microarray experiments showed an inverse relationship between the difference between sample pairs in probe variance and the relative amount of dsDNA. Approximately 15% of probes showed between-sample variation (P < 0.05) when the dsDNA percentage was between 12% and 35%. In contrast, only 3% of probes showed between-sample variation when the dsDNA percentage was 69% and 72%. Replication experiments of the 35% dsDNA and 72% dsDNA samples were used to separate sample variation from probe replication variation. The estimated SD of the sample-to-sample variation and of the probe replicates was lower in 72% dsDNA samples than in 35% dsDNA samples. Variation in the relative amount of double-stranded cDNA synthesized can be an important component of the imprecision in T7 RNA polymerase-based microarray expression analysis. © 2013 American Association for Clinical Chemistry
Prostate Cancer Prevention Through Induction of Phase 2 Enzymes
2001-04-01
enzymes. During our Phase I Award, we identified sulforaphane as the most potent inducer of carcinogen defenses in the prostate cell. We have...characterized global effects of sulforaphane in prostate cancer cell lines using cDNA microarray technology that allows large-scale determination of changes...of sulforaphane ) and decreased risk of prostate cancer. These findings argue strongly for a preventive intervention trial involving supplementation
Advances in diagnostic ultrasonography.
Reef, V B
1991-08-01
A wide variety of ultrasonographic equipment currently is available for use in equine practice, but no one machine is optimal for every type of imaging. Image quality is the most important factor in equipment selection once the needs of the practitioner are ascertained. The transducer frequencies available, transducer footprints, depth of field displayed, frame rate, gray scale, simultaneous electrocardiography, Doppler, and functions to modify the image are all important considerations. The ability to make measurements off of videocassette recorder playback and future upgradability should be evaluated. Linear array and sector technology are the backbone of equine ultrasonography today. Linear array technology is most useful for a high-volume broodmare practice, whereas sector technology is ideal for a more general equine practice. The curved or convex linear scanner has more applications than the standard linear array and is equipped with the linear array rectal probe, which provides the equine practitioner with a more versatile unit for equine ultrasonographic evaluations. The annular array and phased array systems have improved image quality, but each has its own limitations. The new sector scanners still provide the most versatile affordable equipment for equine general practice.
Performance, size, mass, and cost estimates for projected 1kW EOL Si, InP, and GaAs arrays
NASA Technical Reports Server (NTRS)
Slifer, Luther W., Jr.
1991-01-01
One method of evaluating the potential of emerging solar cell and array technologies is to compare their projected capabilities in space flight applications to those of established Si solar cells and arrays. Such an application-oriented comparison provides an integrated view of the elemental comparisons of efficiency, radiation resistance, temperature sensitivity, size, mass, and cost in combination. In addition, the assumptions necessary to make the comparisons provide insights helpful toward determining necessary areas of development or evaluation. Finally, as developments and evaluations progress, the results can be used in more precisely defining the overall potential of the new technologies in comparison to existing technologies. The projected capabilities of Si, InP, and GaAs cells and arrays are compared.
Ultralow-Background Large-Format Bolometer Arrays
NASA Technical Reports Server (NTRS)
Benford, Dominic; Chervenak, Jay; Irwin, Kent; Moseley, S. Harvey; Oegerle, William (Technical Monitor)
2002-01-01
In the coming decade, work will commence in earnest on large cryogenic far-infrared telescopes and interferometers. All such observatories - for example, SAFIR, SPIRIT, and SPECS - require large format, two dimensional arrays of close-packed detectors capable of reaching the fundamental limits imposed by the very low photon backgrounds present in deep space. In the near term, bolometer array architectures which permit 1000 pixels - perhaps sufficient for the next generation of space-based instruments - can be arrayed efficiently. Demonstrating the necessary performance, with Noise Equivalent Powers (NEPs) of order 10-20 W/square root of Hz, will be a hurdle in the coming years. Superconducting bolometer arrays are a promising technology for providing both the performance and the array size necessary. We discuss the requirements for future detector arrays in the far-infrared and submillimeter, describe the parameters of superconducting bolometer arrays able to meet these requirements, and detail the present and near future technology of superconducting bolometer arrays. Of particular note is the coming development of large format planar arrays with absorber-coupled and antenna-coupled bolometers.
An update on SCARLET hardware development and flight programs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jones, P.A.; Murphy, D.M.; Piszczor, M.F.
1995-10-01
Solar Concentrator Array with Refractive Linear Element Technology (SCARLET) is one of the first practical photovoltaic concentrator array technologies that offers a number of benefits for space applications (i.e. high array efficiency, protection from space radiation effects, a relatively light weight system, minimized plasma interactions, etc.) The line-focus concentrator concept, however, also offers two very important advantages: (1) low-cost mass production potential of the lens material; and (2) relaxation of precise array tracking requirements to only a single axis. These benefits offer unique capabilities to both commercial and government spacecraft users, specifically those interested in high radiation missions, such asmore » MEO orbits, and electric-powered propulsion LEO-to-GEO orbit raising applications. SCARLET is an aggressive hardware development and flight validation program sponsored by the Ballistic Missile Defense Organization (BMDO) and NASA Lewis Research Center. Its intent is to bring technology to the level of performance and validation necessary for use by various government and commercial programs. The first phase of the SCARLET program culminated with the design, development and fabrication of a small concentrator array for flight on the METEOR satellite. This hardware will be the first in-space demonstration of concentrator technology at the `array level` and will provide valuable in-orbit performance measurements. The METEOR satellite is currently planned for a September/October 1995 launch. The next phase of the program is the development of large array for use by one of the NASA New Millenium Program missions. This hardware will incorporate a number of the significant improvements over the basic METEOR design. This presentation will address the basic SCARLET technology, examine its benefits to users, and describe the expected improvements for future missions.« less
Characterization and simulation of cDNA microarray spots using a novel mathematical model
Kim, Hye Young; Lee, Seo Eun; Kim, Min Jung; Han, Jin Il; Kim, Bo Kyung; Lee, Yong Sung; Lee, Young Seek; Kim, Jin Hyuk
2007-01-01
Background The quality of cDNA microarray data is crucial for expanding its application to other research areas, such as the study of gene regulatory networks. Despite the fact that a number of algorithms have been suggested to increase the accuracy of microarray gene expression data, it is necessary to obtain reliable microarray images by improving wet-lab experiments. As the first step of a cDNA microarray experiment, spotting cDNA probes is critical to determining the quality of spot images. Results We developed a governing equation of cDNA deposition during evaporation of a drop in the microarray spotting process. The governing equation included four parameters: the surface site density on the support, the extrapolated equilibrium constant for the binding of cDNA molecules with surface sites on glass slides, the macromolecular interaction factor, and the volume constant of a drop of cDNA solution. We simulated cDNA deposition from the single model equation by varying the value of the parameters. The morphology of the resulting cDNA deposit can be classified into three types: a doughnut shape, a peak shape, and a volcano shape. The spot morphology can be changed into a flat shape by varying the experimental conditions while considering the parameters of the governing equation of cDNA deposition. The four parameters were estimated by fitting the governing equation to the real microarray images. With the results of the simulation and the parameter estimation, the phenomenon of the formation of cDNA deposits in each type was investigated. Conclusion This study explains how various spot shapes can exist and suggests which parameters are to be adjusted for obtaining a good spot. This system is able to explore the cDNA microarray spotting process in a predictable, manageable and descriptive manner. We hope it can provide a way to predict the incidents that can occur during a real cDNA microarray experiment, and produce useful data for several research applications involving cDNA microarrays. PMID:18096047
Smart Energy Cryo-refrigerator Technology for the next generation Very Large Array
NASA Astrophysics Data System (ADS)
Spagna, Stefano
2018-01-01
We describe a “smart energy” cryocooler technology architecture for the next generation Very Large Array that makes use of multiple variable frequency cold heads driven from a single variable speed air cooled compressor. Preliminary experiments indicate that the compressor variable flow control, advanced diagnostics, and the cryo-refrigerator low vibration, provide a unique energy efficient capability for the very large number of antennas that will be employed in this array.
NASA Astrophysics Data System (ADS)
Yoo, Byungseok
2011-12-01
In almost all industries of mechanical, aerospace, and civil engineering fields, structural health monitoring (SHM) technology is essentially required for providing the reliable information of structural integrity of safety-critical structures, which can help reduce the risk of unexpected and sometimes catastrophic failures, and also offer cost-effective inspection and maintenance of the structures. State of the art SHM research on structural damage diagnosis is focused on developing global and real-time technologies to identify the existence, location, extent, and type of damage. In order to detect and monitor the structural damage in plate-like structures, SHM technology based on guided Lamb wave (GLW) interrogation is becoming more attractive due to its potential benefits such as large inspection area coverage in short time, simple inspection mechanism, and sensitivity to small damage. However, the GLW method has a few critical issues such as dispersion nature, mode conversion and separation, and multiple-mode existence. Phased array technique widely used in all aspects of civil, military, science, and medical industry fields may be employed to resolve the drawbacks of the GLW method. The GLW-based phased array approach is able to effectively examine and analyze complicated structural vibration responses in thin plate structures. Because the phased sensor array operates as a spatial filter for the GLW signals, the array signal processing method can enhance a desired signal component at a specific direction while eliminating other signal components from other directions. This dissertation presents the development, the experimental validation, and the damage detection applications of an innovative signal processing algorithm based on two-dimensional (2-D) spiral phased array in conjunction with the GLW interrogation technique. It starts with general backgrounds of SHM and the associated technology including the GLW interrogation method. Then, it is focused on the fundamentals of the GLW-based phased array approach and the development of an innovative signal processing algorithm associated with the 2-D spiral phased sensor array. The SHM approach based on array responses determined by the proposed phased array algorithm implementation is addressed. The experimental validation of the GLW-based 2-D spiral phased array technology and the associated damage detection applications to thin isotropic plate and anisotropic composite plate structures are presented.
Sockeye salmon evolution, ecology, and management
Woody, Carol Ann
2007-01-01
This collection of articles and photographs gives managers a good idea of recent research into what the sockeye salmon is and does, covering such topics as the vulnerability and value of sockeye salmon ecotypes, their homing ability, using new technologies to monitor reproduction, DNA and a founder event in the Lake Clark sockeye salmon, marine-derived nutrients, the exploitation of large prey, dynamic lake spawning migrations by females, variability of sockeye salmon residence, expression profiling using cDNA microarray technology, learning from stable isotropic records of native otolith hatcheries, the amount of data needed to manage sockeye salmon and estimating salmon "escapement."
Promising Results from Three NASA SBIR Solar Array Technology Development Programs
NASA Technical Reports Server (NTRS)
Eskenazi, Mike; White, Steve; Spence, Brian; Douglas, Mark; Glick, Mike; Pavlick, Ariel; Murphy, David; O'Neill, Mark; McDanal, A. J.; Piszczor, Michael
2005-01-01
Results from three NASA SBIR solar array technology programs are presented. The programs discussed are: 1) Thin Film Photovoltaic UltraFlex Solar Array; 2) Low Cost/Mass Electrostatically Clean Solar Array (ESCA); and 3) Stretched Lens Array SquareRigger (SLASR). The purpose of the Thin Film UltraFlex (TFUF) Program is to mature and validate the use of advanced flexible thin film photovoltaics blankets as the electrical subsystem element within an UltraFlex solar array structural system. In this program operational prototype flexible array segments, using United Solar amorphous silicon cells, are being manufactured and tested for the flight qualified UltraFlex structure. In addition, large size (e.g. 10 kW GEO) TFUF wing systems are being designed and analyzed. Thermal cycle and electrical test and analysis results from the TFUF program are presented. The purpose of the second program entitled, Low Cost/Mass Electrostatically Clean Solar Array (ESCA) System, is to develop an Electrostatically Clean Solar Array meeting NASA s design requirements and ready this technology for commercialization and use on the NASA MMS and GED missions. The ESCA designs developed use flight proven materials and processes to create a ESCA system that yields low cost, low mass, high reliability, high power density, and is adaptable to any cell type and coverglass thickness. All program objectives, which included developing specifications, creating ESCA concepts, concept analysis and trade studies, producing detailed designs of the most promising ESCA treatments, manufacturing ESCA demonstration panels, and LEO (2,000 cycles) and GEO (1,350 cycles) thermal cycling testing of the down-selected designs were successfully achieved. The purpose of the third program entitled, "High Power Platform for the Stretched Lens Array," is to develop an extremely lightweight, high efficiency, high power, high voltage, and low stowed volume solar array suitable for very high power (multi-kW to MW) applications. These objectives are achieved by combining two cutting edge technologies, the SquareRigger solar array structure and the Stretched Lens Array (SLA). The SLA SquareRigger solar array is termed SLASR. All program objectives, which included developing specifications, creating preliminary designs for a near-term SLASR, detailed structural, mass, power, and sizing analyses, fabrication and power testing of a functional flight-like SLASR solar blanket, were successfully achieved.
Elevated NIBP/TRAPPC9 mediates tumorigenesis of cancer cells through NFκB signaling
Wang, Hong; Yang, Wensheng; Li, Fang; Yang, Fan; Yu, Daohai; Ramsey, Frederick V.; Tuszyski, George P.; Hu, Wenhui
2015-01-01
Regulatory mechanisms underlying constitutive and inducible NFκB activation in cancer remain largely unknown. Here we investigated whether a novel NIK- and IKK2-binding protein (NIBP) is required for maintaining malignancy of cancer cells in an NFκB-dependent manner. Real-time polymerase chain reaction analysis of a human cancer survey tissue-scan cDNA array, immunostaining of a human frozen tumor tissue array and immunoblotting of a high-density reverse-phase cancer protein lysate array showed that NIBP is extensively expressed in most tumor tissues, particularly in breast and colon cancer. Lentivirus-mediated NIBP shRNA knockdown significantly inhibited the growth/proliferation, invasion/migration, colony formation and xenograft tumorigenesis of breast (MDA-MB-231) or colon (HCT116) cancer cells. NIBP overexpression in HCT116 cells promoted cell proliferation, migration and colony formation. Mechanistically, NIBP knockdown in cancer cells inhibited cytokine-induced activation of NFκB luciferase reporter, thus sensitizing the cells to TNFα-induced apoptosis. Endogenous NIBP bound specifically to the phosphorylated IKK2 in a TNFα-dependent manner. NIBP knockdown transiently attenuated TNFα-stimulated phosphorylation of IKK2/p65 and degradation of IκBα. In contrast, NIBP overexpression enhanced TNFα-induced NFκB activation, thus inhibiting constitutive and TNFα-induced apoptosis. Collectively, our data identified important roles of NIBP in promoting tumorigenesis via NFκΒ signaling, spotlighting NIBP as a promising target in cancer therapeutic intervention. PMID:25704885
High-density functional-RNA arrays as a versatile platform for studying RNA-based interactions.
Phillips, Jack O; Butt, Louise E; Henderson, Charlotte A; Devonshire, Martin; Healy, Jess; Conway, Stuart J; Locker, Nicolas; Pickford, Andrew R; Vincent, Helen A; Callaghan, Anastasia J
2018-05-28
We are just beginning to unravel the myriad of interactions in which non-coding RNAs participate. The intricate RNA interactome is the foundation of many biological processes, including bacterial virulence and human disease, and represents unexploited resources for the development of potential therapeutic interventions. However, identifying specific associations of a given RNA from the multitude of possible binding partners within the cell requires robust high-throughput systems for their rapid screening. Here, we present the first demonstration of functional-RNA arrays as a novel platform technology designed for the study of such interactions using immobilized, active RNAs. We have generated high-density RNA arrays by an innovative method involving surface-capture of in vitro transcribed RNAs. This approach has significant advantages over existing technologies, particularly in its versatility in regards to binding partner character. Indeed, proof-of-principle application of RNA arrays to both RNA-small molecule and RNA-RNA pairings is demonstrated, highlighting their potential as a platform technology for mapping RNA-based networks and for pharmaceutical screening. Furthermore, the simplicity of the method supports greater user-accessibility over currently available technologies. We anticipate that functional-RNA arrays will find broad utility in the expanding field of RNA characterization.
Chronic, percutaneous connector for electrical recording and stimulation with microelectrode arrays.
Shah, Kedar G; Lee, Kye Young; Tolosa, Vanessa; Tooker, Angela; Felix, Sarah; Benett, William; Pannu, Satinderpall
2014-01-01
The translation of advances in neural stimulation and recording research into clinical practice hinges on the ability to perform chronic experiments in awake and behaving animal models. Advances in microelectrode array technology, most notably flexible polymer arrays, have significantly improved reliability of the neural interface. However, electrical connector technology has lagged and is prone to failure from non-biocompatibility, large size, contamination, corrosion, and difficulty of use. We present a novel chronic, percutaneous electrical connector system that is suitable for neural stimulation and recording. This system features biocompatible materials, low connect and disconnect forces, passive alignment, and a protective cap during non-use. We have successfully designed, assembled, and tested in vitro both a 16-channel system and a high density 64-channel system. Custom, polyimide, 16-channel, microelectrode arrays were electrically assembled with the connector system and tested using cyclic voltammetry and electrochemical impedance spectroscopy. This connector system is versatile and can be used with a variety of microelectrode array technologies for chronic studies.
High-density Schottky barrier IRCCD sensors for remote sensing applications
NASA Astrophysics Data System (ADS)
Elabd, H.; Tower, J. R.; McCarthy, B. M.
1983-01-01
It is pointed out that the ambitious goals envisaged for the next generation of space-borne sensors challenge the state-of-the-art in solid-state imaging technology. Studies are being conducted with the aim to provide focal plane array technology suitable for use in future Multispectral Linear Array (MLA) earth resource instruments. An important new technology for IR-image sensors involves the use of monolithic Schottky barrier infrared charge-coupled device arrays. This technology is suitable for earth sensing applications in which moderate quantum efficiency and intermediate operating temperatures are required. This IR sensor can be fabricated by using standard integrated circuit (IC) processing techniques, and it is possible to employ commercial IC grade silicon. For this reason, it is feasible to construct Schottky barrier area and line arrays with large numbers of elements and high-density designs. A Pd2Si Schottky barrier sensor for multispectral imaging in the 1 to 3.5 micron band is under development.
Latest developments of 10μm pitch HgCdTe diode array from the legacy to the extrinsic technology
NASA Astrophysics Data System (ADS)
Péré-Laperne, Nicolas; Berthoz, Jocelyn; Taalat, Rachid; Rubaldo, Laurent; Kerlain, Alexandre; Carrère, Emmanuel; Dargent, Loïc.
2016-05-01
Sofradir recently presented Daphnis, its latest 10 μm pitch product family. Both Daphnis XGA and HD720 are 10μm pitch mid-wave infrared focal plane array. Development of small pixel pitch is opening the way to very compact products with a high spatial resolution. This new product is taking part in the HOT technology competition allowing reductions in size, weight and power of the overall package. This paper presents the recent developments achieved at Sofradir to make the 10μm pitch HgCdTe focal plane array based on the legacy technology. Electrical and electro-optical characterizations are presented to define the appropriate design of 10μm pitch diode array. The technological tradeoffs are explained to lower the dark current, to keep high quantum efficiency with a high operability above 110K, F/4. Also, Sofradir recently achieved outstanding Modulation Transfer Function (MTF) demonstration at this pixel pitch, which clearly demonstrates the benefit to users of adopting 10μm pixel pitch focal plane array based detectors. Furthermore, the HgCdTe technology has demonstrated an increase of the operating temperature, plus 40K, moving from the legacy to the P-on-n one at a 15μm pitch in mid-wave band. The first realizations using the extrinsic P-on-n technology and the characterizations of diodes with a 10μm pitch neighborhood will be presented in both mid-wave and long-wave bands.
Integrated infrared detector arrays for low-background astronomy
NASA Technical Reports Server (NTRS)
Mccreight, C. R.
1979-01-01
Existing integrated infrared detector array technology is being evaluated under low-background conditions to determine its applicability in orbiting astronomical applications where extended integration times and photometric accuracy are of interest. Preliminary performance results of a 1 x 20 elements InSb CCD array under simulated astronomical conditions are presented. Using the findings of these tests, improved linear- and area-array technology will be developed for use in NASA programs such as the Shuttle Infrared Telescope Facility. For wavelengths less than 30 microns, extrinsic silicon and intrinsic arrays with CCD readout will be evaluated and improved as required, while multiplexed arrays of Ge:Ga for wavelengths in the range 30 to 120 microns will be developed as fundamental understanding of this material improves. Future efforts will include development of improved drive and readout circuitry, and consideration of alternate multiplexing schemes.
Xie, Dan; Zhang, Honghai; Shu, Xiayun; Xiao, Junfeng
2012-07-02
The paper reports an effective method to fabricate micro-lens arrays with the ultraviolet-curable polymer, using an original pneumatically diaphragm-driven drop-on-demand inkjet system. An array of plano convex micro-lenses can be formed on the glass substrate due to surface tension and hydrophobic effect. The micro-lens arrays have uniform focusing function, smooth and real planar surface. The fabrication process showed good repeatability as well, fifty micro-lenses randomly selected form 9 × 9 miro-lens array with an average diameter of 333.28μm showed 1.1% variations. Also, the focal length, the surface roughness and optical property of the fabricated micro-lenses are measured, analyzed and proved satisfactory. The technique shows great potential for fabricating polymer micro-lens arrays with high flexibility, simple technological process and low production cost.
Leng, Yuankui
2017-01-01
Spectrometrically or optically encoded microsphere based suspension array technology (SAT) is applicable to the high-throughput, simultaneous detection of multiple analytes within a small, single sample volume. Thanks to the rapid development of nanotechnology, tremendous progress has been made in the multiplexed detecting capability, sensitivity, and photostability of suspension arrays. In this review, we first focus on the current stock of nanoparticle-based barcodes as well as the manufacturing technologies required for their production. We then move on to discuss all existing barcode-based bioanalysis patterns, including the various labels used in suspension arrays, label-free platforms, signal amplification methods, and fluorescence resonance energy transfer (FRET)-based platforms. We then introduce automatic platforms for suspension arrays that use superparamagnetic nanoparticle-based microspheres. Finally, we summarize the current challenges and their proposed solutions, which are centered on improving encoding capacities, alternative probe possibilities, nonspecificity suppression, directional immobilization, and “point of care” platforms. Throughout this review, we aim to provide a comprehensive guide for the design of suspension arrays, with the goal of improving their performance in areas such as multiplexing capacity, throughput, sensitivity, and cost effectiveness. We hope that our summary on the state-of-the-art development of these arrays, our commentary on future challenges, and some proposed avenues for further advances will help drive the development of suspension array technology and its related fields. PMID:26021602
The impact of solar cell technology on planar solar array performance
NASA Technical Reports Server (NTRS)
Mills, Michael W.; Kurland, Richard M.
1989-01-01
The results of a study into the potential impact of advanced solar cell technologies on the characteristics (weight, cost, area) of typical planar solar arrays designed for low, medium and geosynchronous altitude earth orbits are discussed. The study considered planar solar array substrate designs of lightweight, rigid-panel graphite epoxy and ultra-lightweight Kapton. The study proposed to answer the following questions: Do improved cell characteristics translate into array-level weight, size and cost improvements; What is the relative importance of cell efficiency, weight and cost with respect to array-level performance; How does mission orbital environment affect array-level performance. Comparisons were made at the array level including all mechanisms, hinges, booms, and harnesses. Array designs were sized to provide 5kW of array power (not spacecraft bus power, which is system dependent but can be scaled from given values). The study used important grass roots issues such as use of the GaAs radiation damage coefficients as determined by Anspaugh. Detailed costing was prepared, including cell and cover costs, and manufacturing attrition rates for the various cell types.
Gallium arsenide solar array subsystem study
NASA Technical Reports Server (NTRS)
Miller, F. Q.
1982-01-01
The effects on life cycle costs of a number of technology areas are examined for a gallium arsenide space solar array. Four specific configurations were addressed: (1) a 250 KWe LEO mission - planer array; (2) a 250 KWe LEO mission - with concentration; (3) a 50 KWe GEO mission planer array; (4) a 50 KWe GEO mission - with concentration. For each configuration, a baseline system conceptual design was developed and the life cycle costs estimated in detail. The baseline system requirements and design technologies were then varied and their relationships to life cycle costs quantified. For example, the thermal characteristics of the baseline design are determined by the array materials and masses. The thermal characteristics in turn determine configuration, performance, and hence life cycle costs.
NASA Technical Reports Server (NTRS)
1982-01-01
Technologies that will enable the private sector to manufacture and widely use photovoltaic systems for the generation of electricity in residential, commercial, industrial, and government applications at a cost per watt that is competitive with other means is investigated. Silicon refinement processes, advanced silicon sheet growth techniques, solar cell development, encapsulation, automated fabrication process technology, advanced module/array design, and module/array test and evaluation techniques are developed.
SCARLET Photovoltaic Concentrator Array Selected for Flight Under NASA's New Millennium Program
NASA Technical Reports Server (NTRS)
Piszczor, Michael F., Jr.
1997-01-01
The NASA Lewis Research Center continues to demonstrate its expertise in the development and implementation of advanced space power systems. For example, during the past year, the NASA New Millennium Program selected the Solar Concentrator Array with Refractive Linear Element Technology (SCARLET) photovoltaic array as the power system for its Deep Space-1 (DS-1) mission. This Jet Propulsion Laboratory (JPL) managed DS-1 mission, which represents the first operational flight of a photovoltaic concentrator array, will provide a baseline for the use of this technology in a variety of future government and commercial applications. SCARLET is a joint NASA Lewis/Ballistic Missile Defense Organization program to develop advanced photovoltaic array technology that uses a unique refractive concentrator design to focus sunlight onto a line of photovoltaic cells located below the optical element. The general concept is based on previous work conducted at Lewis under a Small Business Innovation Research (SBIR) contract with AEC-Able Engineering, Inc., for the Multiple Experiments to Earth Orbit and Return (METEOR) spacecraft. The SCARLET II design selected by the New Millennium Program is a direct adaptation of the smaller SCARLET I array built for METEOR. Even though SCARLET I was lost during a launch failure in October 1995, the hardware (designed, built, and flight qualified within 6 months) provided invaluable information and experience that led to the selection of this technology as the primary power source for DS-1.
The DS1 Mission and the Validation of the SCARLET Advanced Array
NASA Technical Reports Server (NTRS)
Stella, Paul M.; Nieraeth, Donald G.; Murphy, David M.; Eskenazi, Michael I.
2000-01-01
On October 24, 1998, the first of the NASA New Millenium Spacecraft, DS1, was successfully launched into Space. The objectives for this spacecraft are to test advanced technologies that can reduce the cost or risk of future missions. One of these technologies is the SCARLET concentrating solar array. Although part of the advanced technology validation study, the array is also the spacecraft's power source. Funded by BMDO, the SCARLET concentrator solar array is the first application of a refractive lens concentrator designed for space applications. As part of the DS1 validation process, the amount of diagnostics data that will be acquired is more extensive than would be the norm for a more conventional solar array. These data include temperature measurements at numerous locations on the 2-wing, 4-panel per wing, solar array. For each panel, one 5-cell module in one of the circuit strings is wired so that a complete I-V curve can be obtained. This data is used to verify sun pointing accuracy and array output performance. In addition, the spacecraft power load can be varied in a number of discrete steps from a small fraction of the array total power capability, up to maximum power. For each of the power loads, array operating voltage can be measured along with the current output from each wing. Preliminary in-space measurements suggest SCARLET performance is within one (1) percent of predictions made from ground data. This paper will briefly discuss the SCARLET configuration and critical features. Emphasis will be given to the results of the in-space validation, including array performance as a function of changing solar distance and array performance compared to pre-launch predictions.
Shiraishi, H; Ishikura, S; Matsuura, K; Deyashiki, Y; Ninomiya, M; Sakai, S; Hara, A
1998-01-01
Human liver contains three isoforms (DD1, DD2 and DD4) of dihydrodiol dehydrogenase with 20alpha- or 3alpha-hydroxysteroid dehydrogenase activity; the dehydrogenases belong to the aldo-oxo reductase (AKR) superfamily. cDNA species encoding DD1 and DD4 have been identified. However, four cDNA species with more than 99% sequence identity have been cloned and are compatible with a partial amino acid sequence of DD2. In this study we have isolated a cDNA clone encoding DD2, which was confirmed by comparison of the properties of the recombinant and hepatic enzymes. This cDNA showed differences of one, two, four and five nucleotides from the previously reported four cDNA species for a dehydrogenase of human colon carcinoma HT29 cells, human prostatic 3alpha-hydroxysteroid dehydrogenase, a human liver 3alpha-hydroxysteroid dehydrogenase-like protein and chlordecone reductase-like protein respectively. Expression of mRNA species for the five similar cDNA species in 20 liver samples and 10 other different tissue samples was examined by reverse transcriptase-mediated PCR with specific primers followed by diagnostic restriction with endonucleases. All the tissues expressed only one mRNA species corresponding to the newly identified cDNA for DD2: mRNA transcripts corresponding to the other cDNA species were not detected. We suggest that the new cDNA is derived from the principal gene for DD2, which has been named AKR1C2 by a new nomenclature for the AKR superfamily. It is possible that some of the other cDNA species previously reported are rare allelic variants of this gene. PMID:9716498
Patterns Cancer Prevention Through Induction of Phase 2 Enzymes
2003-04-01
2) enzymes. During our Phase I Award, we identified sulforaphane as the most potent inducer of carcinogen defenses in the prostate cell. We have...characterized global effects of sulforaphane in prostate cancer cell lines using cDNA microarray technology that allows large-scale determination of...changes in gene expression. These findings argue strongly for a preventive intervention trial involving with sulforaphane . During our Phase 2 Award, we used
Mora-Castilla, Sergio; To, Cuong; Vaezeslami, Soheila; Morey, Robert; Srinivasan, Srimeenakshi; Dumdie, Jennifer N; Cook-Andersen, Heidi; Jenkins, Joby; Laurent, Louise C
2016-08-01
As the cost of next-generation sequencing has decreased, library preparation costs have become a more significant proportion of the total cost, especially for high-throughput applications such as single-cell RNA profiling. Here, we have applied novel technologies to scale down reaction volumes for library preparation. Our system consisted of in vitro differentiated human embryonic stem cells representing two stages of pancreatic differentiation, for which we prepared multiple biological and technical replicates. We used the Fluidigm (San Francisco, CA) C1 single-cell Autoprep System for single-cell complementary DNA (cDNA) generation and an enzyme-based tagmentation system (Nextera XT; Illumina, San Diego, CA) with a nanoliter liquid handler (mosquito HTS; TTP Labtech, Royston, UK) for library preparation, reducing the reaction volume down to 2 µL and using as little as 20 pg of input cDNA. The resulting sequencing data were bioinformatically analyzed and correlated among the different library reaction volumes. Our results showed that decreasing the reaction volume did not interfere with the quality or the reproducibility of the sequencing data, and the transcriptional data from the scaled-down libraries allowed us to distinguish between single cells. Thus, we have developed a process to enable efficient and cost-effective high-throughput single-cell transcriptome sequencing. © 2016 Society for Laboratory Automation and Screening.
Method for replicating an array of nucleic acid probes
Cantor, Charles R.; Przetakiewicz, Marek; Smith, Cassandra L.; Sano, Takeshi
1998-01-01
The invention relates to the replication of probe arrays and methods for replicating arrays of probes which are useful for the large scale manufacture of diagnostic aids used to screen biological samples for specific target sequences. Arrays created using PCR technology may comprise probes with 5'- and/or 3'-overhangs.
Qi, Jing; Dong, Zhen; Zhang, Yu-Xing
2015-12-01
The aim of the present study was to genetically modify plantlets of the Chinese yali pear to reduce their expression of ripening-associated 1-aminocyclopropane-1-carboxylic acid oxidase (ACO) and therefore increase the shelf-life of the fruit. Primers were designed with selectivity for the conserved regions of published ACO gene sequences, and yali complementary DNA (cDNA) cloning was performed by reverse transcription quantitative polymerase chain reaction (PCR). The obtained cDNA fragment contained 831 base pairs, encoding 276 amino acid residues, and shared no less than 94% nucleotide sequence identity with other published ACO genes. The cDNA fragment was inversely inserted into a pBI121 expression vector, between the cauliflower mosaic virus 35S promoter and the nopaline synthase terminator, in order to construct the anti‑sense expression vector of the ACO gene; it was transfected into cultured yali plants using Agrobacterium LBA4404. Four independent transgenic lines of pear plantlets were obtained and validated by PCR analysis. A Southern blot assay revealed that there were three transgenic lines containing a single copy of exogenous gene and one line with double copies. The present study provided germplasm resources for the cultivation of novel storage varieties of pears, therefore providing a reference for further applications of anti‑sense RNA technology in the genetic improvement of pears and other fruit.
Role of messenger RNA-ribosome complex in complementary DNA display.
Naimuddin, Mohammed; Ohtsuka, Isao; Kitamura, Koichiro; Kudou, Motonori; Kimura, Shinnosuke
2013-07-15
In vitro display technologies such as ribosome display and messenger RNA (mRNA)/complementary DNA (cDNA) display are powerful methods that can generate library diversities on the order of 10(10-14). However, in mRNA and cDNA display methods, the end use diversity is two orders of magnitude lower than initial diversity and is dependent on the downstream processes that act as limiting factors. We found that in our previous cDNA display protocol, the purification of protein fusions by the use of streptavidin matrices from cell-free translation mixtures had poor efficiency (∼10-15%) that seriously affected the diversity of the purified library. Here, we have investigated and optimized the protocols that provided remarkable purification efficiencies. The stalled ribosome in the mRNA-ribosome complex was found to impede this purification efficiency. Among the various conditions tested, destabilization of ribosomes by appropriate concentration of metal chelating agents in combination with an optimal temperature of 30°C were found to be crucial and effective for nearly complete isolation of protein fusions from the cell-free translation system. Thus, this protocol provided 8- to 10-fold increased efficiency of purification over the previous method and results in retaining the diversity of the library by approximately an order of magnitude-important for directed evolution. We also discuss the possible effects in the fabrication of protein chips. Copyright © 2013 Elsevier Inc. All rights reserved.
Characterization of silicon-gate CMOS/SOS integrated circuits processed with ion implantation
NASA Technical Reports Server (NTRS)
Woo, D. S.
1980-01-01
The double layer metallization technology applied on p type silicon gate CMOS/SOS integrated circuits is described. A smooth metal surface was obtained by using the 2% Si-sputtered Al. More than 10% probe yield was achieved on solar cell controller circuit TCS136 (or MSFC-SC101). Reliability tests were performed on 15 arrays at 150 C. Only three arrays failed during the burn in, and 18 arrays out of 22 functioning arrays maintained the leakage current below 100 milli-A. Analysis indicates that this technology will be a viable process if the metal short circuit problem between the two metals can be reduced.
High-throughput genotyping of hop (Humulus lupulus L.) utilising diversity arrays technology (DArT)
USDA-ARS?s Scientific Manuscript database
Implementation of molecular methods in hop breeding is dependent on the availability of sizeable numbers of polymorphic markers and a comprehensive understanding of genetic variation. Diversity Arrays Technology (DArT) is a high-throughput cost-effective method for the discovery of large numbers of...
Marques, M Carmen; Alonso-Cantabrana, Hugo; Forment, Javier; Arribas, Raquel; Alamar, Santiago; Conejero, Vicente; Perez-Amador, Miguel A
2009-01-01
Background Interpretation of ever-increasing raw sequence information generated by modern genome sequencing technologies faces multiple challenges, such as gene function analysis and genome annotation. Indeed, nearly 40% of genes in plants encode proteins of unknown function. Functional characterization of these genes is one of the main challenges in modern biology. In this regard, the availability of full-length cDNA clones may fill in the gap created between sequence information and biological knowledge. Full-length cDNA clones facilitate functional analysis of the corresponding genes enabling manipulation of their expression in heterologous systems and the generation of a variety of tagged versions of the native protein. In addition, the development of full-length cDNA sequences has the power to improve the quality of genome annotation. Results We developed an integrated method to generate a new normalized EST collection enriched in full-length and rare transcripts of different citrus species from multiple tissues and developmental stages. We constructed a total of 15 cDNA libraries, from which we isolated 10,898 high-quality ESTs representing 6142 different genes. Percentages of redundancy and proportion of full-length clones range from 8 to 33, and 67 to 85, respectively, indicating good efficiency of the approach employed. The new EST collection adds 2113 new citrus ESTs, representing 1831 unigenes, to the collection of citrus genes available in the public databases. To facilitate functional analysis, cDNAs were introduced in a Gateway-based cloning vector for high-throughput functional analysis of genes in planta. Herein, we describe the technical methods used in the library construction, sequence analysis of clones and the overexpression of CitrSEP, a citrus homolog to the Arabidopsis SEP3 gene, in Arabidopsis as an example of a practical application of the engineered Gateway vector for functional analysis. Conclusion The new EST collection denotes an important step towards the identification of all genes in the citrus genome. Furthermore, public availability of the cDNA clones generated in this study, and not only their sequence, enables testing of the biological function of the genes represented in the collection. Expression of the citrus SEP3 homologue, CitrSEP, in Arabidopsis results in early flowering, along with other phenotypes resembling the over-expression of the Arabidopsis SEPALLATA genes. Our findings suggest that the members of the SEP gene family play similar roles in these quite distant plant species. PMID:19747386
Report of the Power Sub systems Panel. [spacecraft instrumentation technology
NASA Technical Reports Server (NTRS)
1979-01-01
Problems in spacecraft power system design, testing, integration, and operation are identified and solutions are defined. The specific technology development problems discussed include substorm and plasma design data, modeling of the power subsystem and components, power system monitoring and degraded system management, rotary joints for transmission of power and signals, nickel cadmium battery manufacturing and application, on-array power management, high voltage technology, and solar arrays.
Hemispherical array of sensors with contractively wrapped polymer petals for flow sensing
NASA Astrophysics Data System (ADS)
Kanhere, Elgar; Wang, Nan; Kottapalli, Ajay Giri Prakash; Miao, Jianmin; Triantafyllou, Michael
2017-11-01
Hemispherical arrays have inherent advantages that allow simultaneous detection of flow speed and direction due to their shape. Though MEMS technology has progressed leaps and bounds, fabrication of array of sensors on a hemispherical surface is still a challenge. In this work, a novel approach of constructing hemispherical array is presented which employs a technique of contractively wrapping a hemispherical surface with flexible liquid crystal polymer petals. This approach also leverages the offerings from rapid prototyping technology and established standard MEMS fabrication processes. Hemispherical arrays of piezoresistive sensors are constructed with two types of petal wrappings, 4-petals and 8-petals, on a dome. The flow sensing and direction detection abilities of the dome are evaluated through experiments in wind tunnel. Experimental results demonstrate that a dome equipped with a dense array of sensors can provide information pertaining to the stimulus, through visualization of output profile over the entire surface.
Terahertz Array Receivers with Integrated Antennas
NASA Technical Reports Server (NTRS)
Chattopadhyay, Goutam; Llombart, Nuria; Lee, Choonsup; Jung, Cecile; Lin, Robert; Cooper, Ken B.; Reck, Theodore; Siles, Jose; Schlecht, Erich; Peralta, Alessandro;
2011-01-01
Highly sensitive terahertz heterodyne receivers have been mostly single-pixel. However, now there is a real need of multi-pixel array receivers at these frequencies driven by the science and instrument requirements. In this paper we explore various receiver font-end and antenna architectures for use in multi-pixel integrated arrays at terahertz frequencies. Development of wafer-level integrated terahertz receiver front-end by using advanced semiconductor fabrication technologies has progressed very well over the past few years. Novel stacking of micro-machined silicon wafers which allows for the 3-dimensional integration of various terahertz receiver components in extremely small packages has made it possible to design multi-pixel heterodyne arrays. One of the critical technologies to achieve fully integrated system is the antenna arrays compatible with the receiver array architecture. In this paper we explore different receiver and antenna architectures for multi-pixel heterodyne and direct detector arrays for various applications such as multi-pixel high resolution spectrometer and imaging radar at terahertz frequencies.
NASA Astrophysics Data System (ADS)
Simoens, François; Meilhan, Jérôme; Nicolas, Jean-Alain
2015-10-01
Sensitive and large-format terahertz focal plane arrays (FPAs) integrated in compact and hand-held cameras that deliver real-time terahertz (THz) imaging are required for many application fields, such as non-destructive testing (NDT), security, quality control of food, and agricultural products industry. Two technologies of uncooled THz arrays that are being studied at CEA-Leti, i.e., bolometer and complementary metal oxide semiconductor (CMOS) field effect transistors (FET), are able to meet these requirements. This paper reminds the followed technological approaches and focuses on the latest modeling and performance analysis. The capabilities of application of these arrays to NDT and security are then demonstrated with experimental tests. In particular, high technological maturity of the THz bolometer camera is illustrated with fast scanning of large field of view of opaque scenes achieved in a complete body scanner prototype.
ASIC Readout Circuit Architecture for Large Geiger Photodiode Arrays
NASA Technical Reports Server (NTRS)
Vasile, Stefan; Lipson, Jerold
2012-01-01
The objective of this work was to develop a new class of readout integrated circuit (ROIC) arrays to be operated with Geiger avalanche photodiode (GPD) arrays, by integrating multiple functions at the pixel level (smart-pixel or active pixel technology) in 250-nm CMOS (complementary metal oxide semiconductor) processes. In order to pack a maximum of functions within a minimum pixel size, the ROIC array is a full, custom application-specific integrated circuit (ASIC) design using a mixed-signal CMOS process with compact primitive layout cells. The ROIC array was processed to allow assembly in bump-bonding technology with photon-counting infrared detector arrays into 3-D imaging cameras (LADAR). The ROIC architecture was designed to work with either common- anode Si GPD arrays or common-cathode InGaAs GPD arrays. The current ROIC pixel design is hardwired prior to processing one of the two GPD array configurations, and it has the provision to allow soft reconfiguration to either array (to be implemented into the next ROIC array generation). The ROIC pixel architecture implements the Geiger avalanche quenching, bias, reset, and time to digital conversion (TDC) functions in full-digital design, and uses time domain over-sampling (vernier) to allow high temporal resolution at low clock rates, increased data yield, and improved utilization of the laser beam.
Superconducting Bolometer Array Architectures
NASA Technical Reports Server (NTRS)
Benford, Dominic; Chervenak, Jay; Irwin, Kent; Moseley, S. Harvey; Shafer, Rick; Staguhn, Johannes; Wollack, Ed; Oegerle, William (Technical Monitor)
2002-01-01
The next generation of far-infrared and submillimeter instruments require large arrays of detectors containing thousands of elements. These arrays will necessarily be multiplexed, and superconducting bolometer arrays are the most promising present prospect for these detectors. We discuss our current research into superconducting bolometer array technologies, which has recently resulted in the first multiplexed detections of submillimeter light and the first multiplexed astronomical observations. Prototype arrays containing 512 pixels are in production using the Pop-Up Detector (PUD) architecture, which can be extended easily to 1000 pixel arrays. Planar arrays of close-packed bolometers are being developed for the GBT (Green Bank Telescope) and for future space missions. For certain applications, such as a slewed far-infrared sky survey, feedhorncoupling of a large sparsely-filled array of bolometers is desirable, and is being developed using photolithographic feedhorn arrays. Individual detectors have achieved a Noise Equivalent Power (NEP) of -10(exp 17) W/square root of Hz at 300mK, but several orders of magnitude improvement are required and can be reached with existing technology. The testing of such ultralow-background detectors will prove difficult, as this requires optical loading of below IfW. Antenna-coupled bolometer designs have advantages for large format array designs at low powers due to their mode selectivity.
Arrays of probes for positional sequencing by hybridization
Cantor, Charles R [Boston, MA; Prezetakiewiczr, Marek [East Boston, MA; Smith, Cassandra L [Boston, MA; Sano, Takeshi [Waltham, MA
2008-01-15
This invention is directed to methods and reagents useful for sequencing nucleic acid targets utilizing sequencing by hybridization technology comprising probes, arrays of probes and methods whereby sequence information is obtained rapidly and efficiently in discrete packages. That information can be used for the detection, identification, purification and complete or partial sequencing of a particular target nucleic acid. When coupled with a ligation step, these methods can be performed under a single set of hybridization conditions. The invention also relates to the replication of probe arrays and methods for making and replicating arrays of probes which are useful for the large scale manufacture of diagnostic aids used to screen biological samples for specific target sequences. Arrays created using PCR technology may comprise probes with 5'- and/or 3'-overhangs.
Simon, J W; Slabas, A R
1998-09-18
The GenBank database was searched using the E. coli malonyl CoA:ACP transacylase (MCAT) sequence, for plant protein/cDNA sequences corresponding to MCAT, a component of plant fatty acid synthetase (FAS), for which the plant cDNA has not been isolated. A 272-bp Zea mays EST sequence (GenBank accession number: AA030706) was identified which has strong homology to the E. coli MCAT. A PCR derived cDNA probe from Zea mays was used to screen a Brassica napus (rape) cDNA library. This resulted in the isolation of a 1200-bp cDNA clone which encodes an open reading frame corresponding to a protein of 351 amino acids. The protein shows 47% homology to the E. coli MCAT amino acid sequence in the coding region for the mature protein. Expression of a plasmid (pMCATrap2) containing the plant cDNA sequence in Fab D89, an E. coli mutant, in MCAT activity restores growth demonstrating functional complementation and direct function of the cloned cDNA. This is the first functional evidence supporting the identification of a plant cDNA for MCAT.
HLA genotyping by next-generation sequencing of complementary DNA.
Segawa, Hidenobu; Kukita, Yoji; Kato, Kikuya
2017-11-28
Genotyping of the human leucocyte antigen (HLA) is indispensable for various medical treatments. However, unambiguous genotyping is technically challenging due to high polymorphism of the corresponding genomic region. Next-generation sequencing is changing the landscape of genotyping. In addition to high throughput of data, its additional advantage is that DNA templates are derived from single molecules, which is a strong merit for the phasing problem. Although most currently developed technologies use genomic DNA, use of cDNA could enable genotyping with reduced costs in data production and analysis. We thus developed an HLA genotyping system based on next-generation sequencing of cDNA. Each HLA gene was divided into 3 or 4 target regions subjected to PCR amplification and subsequent sequencing with Ion Torrent PGM. The sequence data were then subjected to an automated analysis. The principle of the analysis was to construct candidate sequences generated from all possible combinations of variable bases and arrange them in decreasing order of the number of reads. Upon collecting candidate sequences from all target regions, 2 haplotypes were usually assigned. Cases not assigned 2 haplotypes were forwarded to 4 additional processes: selection of candidate sequences applying more stringent criteria, removal of artificial haplotypes, selection of candidate sequences with a relaxed threshold for sequence matching, and countermeasure for incomplete sequences in the HLA database. The genotyping system was evaluated using 30 samples; the overall accuracy was 97.0% at the field 3 level and 98.3% at the G group level. With one sample, genotyping of DPB1 was not completed due to short read size. We then developed a method for complete sequencing of individual molecules of the DPB1 gene, using the molecular barcode technology. The performance of the automatic genotyping system was comparable to that of systems developed in previous studies. Thus, next-generation sequencing of cDNA is a viable option for HLA genotyping.
Method for replicating an array of nucleic acid probes
Cantor, C.R.; Przetakiewicz, M.; Smith, C.L.; Sano, T.
1998-08-18
The invention relates to the replication of probe arrays and methods for replicating arrays of probes which are useful for the large scale manufacture of diagnostic aids used to screen biological samples for specific target sequences. Arrays created using PCR technology may comprise probes with 5{prime}- and/or 3{prime}-overhangs. 16 figs.
Flat-plate solar array progress and plans
NASA Technical Reports Server (NTRS)
Callaghan, W. T.
1984-01-01
The results of research into the technology of flat-plate solar arrays undertaken in the Flat-Plate Solar Array Project under the sponsorship of the U.S. Department of Energy are surveyed. Topics examined include Si refinement, ribbon-sheet substrate formation, module process sequences, environmental isolation, module engineering and testing, and photovoltaic-array economics.
Measurement of high-voltage and radiation-damage limitations to advanced solar array performance
NASA Technical Reports Server (NTRS)
Guidice, D. A.; Severance, P. S.; Keinhardt, K. C.
1991-01-01
A description is given of the reconfigured Photovoltaic Array Space Power (PASP) Plus experiment: its objectives, solar-array complement, and diagnostic sensors. Results from a successful spaceflight will lead to a better understanding of high-voltage and radiation-damage limitations in the operation of new-technology solar arrays.
NASA Astrophysics Data System (ADS)
Shen, Yannan; Istock, André; Zaman, Anik; Woidt, Carsten; Hillmer, Hartmut
2018-05-01
Miniaturization of optical spectrometers can be achieved by Fabry-Pérot (FP) filter arrays. Each FP filter consists of two parallel highly reflecting mirrors and a resonance cavity in between. Originating from different individual cavity heights, each filter transmits a narrow spectral band (transmission line) with different wavelengths. Considering the fabrication efficiency, plasma enhanced chemical vapor deposition (PECVD) technology is applied to implement the high-optical-quality distributed Bragg reflectors (DBRs), while substrate conformal imprint lithography (one type of nanoimprint technology) is utilized to achieve the multiple cavities in just a single step. The FP filter array fabricated by nanoimprint combined with corresponding detector array builds a so-called "nanospectrometer". However, the silicon nitride and silicon dioxide stacks deposited by PECVD result in a limited stopband width of DBR (i.e., < 100 nm), which then limits the sensing range of filter arrays. However, an extension of the spectral range of filter arrays is desired and the topic of this investigation. In this work, multiple DBRs with different central wavelengths (λ c) are structured, deposited, and combined on a single substrate to enlarge the entire stopband. Cavity arrays are successfully aligned and imprinted over such terrace like surface in a single step. With this method, small chip size of filter arrays can be preserved, and the fabrication procedure of multiple resonance cavities is kept efficient as well. The detecting range of filter arrays is increased from roughly 50 nm with single DBR to 163 nm with three different DBRs.
Application of MEMS Microphone Array Technology to Airframe Noise Measurements
NASA Technical Reports Server (NTRS)
Humphreys, William M., Jr.; Shams, Qamar A.; Graves, Sharon S.; Sealey, Bradley S.; Bartram, Scott M.; Comeaux, Toby
2005-01-01
Current generation microphone directional array instrumentation is capable of extracting accurate noise source location and directivity data on a variety of aircraft components, resulting in significant gains in test productivity. However, with this gain in productivity has come the desire to install larger and more complex arrays in a variety of ground test facilities, creating new challenges for the designers of array systems. To overcome these challenges, a research study was initiated to identify and develop hardware and fabrication technologies which could be used to construct an array system exhibiting acceptable measurement performance but at much lower cost and with much simpler installation requirements. This paper describes an effort to fabricate a 128-sensor array using commercially available Micro-Electro-Mechanical System (MEMS) microphones. The MEMS array was used to acquire noise data for an isolated 26%-scale high-fidelity Boeing 777 landing gear in the Virginia Polytechnic Institute and State University Stability Tunnel across a range of Mach numbers. The overall performance of the array was excellent, and major noise sources were successfully identified from the measurements.
Stretched Lens Array Squarerigger (SLASR) Technology Maturation
NASA Technical Reports Server (NTRS)
O'Neill, Mark; McDanal, A.J.; Howell, Joe; Lollar, Louis; Carrington, Connie; Hoppe, David; Piszczor, Michael; Suszuki, Nantel; Eskenazi, Michael; Aiken, Dan;
2007-01-01
Since April 2005, our team has been underway on a competitively awarded program sponsored by NASA s Exploration Systems Mission Directorate to develop, refine, and mature the unique solar array technology known as Stretched Lens Array SquareRigger (SLASR). SLASR offers an unprecedented portfolio of performance metrics, SLASR offers an unprecedented portfolio of performance metrics, including the following: Areal Power Density = 300 W/m2 (2005) - 400 W/m2 (2008 Target) Specific Power = 300 W/kg (2005) - 500 W/kg (2008 Target) for a Full 100 kW Solar Array Stowed Power = 80 kW/cu m (2005) - 120 kW/m3 (2008 Target) for a Full 100 kW Solar Array Scalable Array Capacity = 100 s of W s to 100 s of kW s Super-Insulated Small Cell Circuit = High-Voltage (300-600 V) Operation at Low Mass Penalty Super-Shielded Small Cell Circuit = Excellent Radiation Hardness at Low Mass Penalty 85% Cell Area Savings = 75% Lower Array Cost per Watt than One-Sun Array Modular, Scalable, & Mass-Producible at MW s per Year Using Existing Processes and Capacities
Phased Array Theory and Technology
1981-07-01
Generalized Array Coordinates 2. Linear, Planar and Circular Art -ays 3. Periodic fwo Dimensional ^rras 4. Grating Lobe Lattices 5. 1’llenienl...formal and low profile antennas, antennas for limited sector coverage, and wide- band array feeds. To aid designers, there is an attempt to give ...ol Vol. 2, Elliott gives convenient formulas lor the directivity of Imear dipole arrays, and derives an especially simple form tor arrays
Development of an Influenza virus protein array using Sortagging technology
Sinisi, Antonia; Popp, Maximilian Wei-Lin; Antos, John M.; Pansegrau, Werner; Savino, Silvana; Nissum, Mikkel; Rappuoli, Rino; Ploegh, Hidde L.; Buti, Ludovico
2013-01-01
Protein array technology is an emerging tool that enables high throughput screening of protein-protein or protein-lipid interactions and identification of immunodominant antigens during the course of a bacterial or viral infection. In this work we developed an Influenza virus protein array using the sortase-mediated transpeptidation reaction known as “Sortagging”. LPETG-tagged Influenza virus proteins from bacterial and eukaryotic cellular extracts were immobilized at their carboxyl-termini onto a pre-activated amine-glass slide coated with a Gly3 linker. Immobilized proteins were revealed by specific antibodies and the newly generated Sortag-protein chip can be used as a device for antigen and/or antibody screening. The specificity of the Sortase A (SrtA) reaction avoids purification steps in array building and allows immobilization of proteins in an oriented fashion. Previously, this versatile technology has been successfully employed for protein labeling and protein conjugation. Here, the tool is implemented to covalently link proteins of a viral genome onto a solid support. The system could readily be scaled up to proteins of larger genomes in order to develop protein arrays for high throughput screening. PMID:22594688
Diversity Arrays Technology (DArT) platform for genotyping and mapping in carrot (Daucus carota L.)
USDA-ARS?s Scientific Manuscript database
Carrot is one of the most important root vegetable crops grown worldwide on more than one million hectares. Its progenitor, wild Daucus carota, is a weed commonly occurring across continents in the temperate climatic zone. Diversity Array Technology (DArT) is a microarray-based molecular marker syst...
Hollow Nanospheres Array Fabrication via Nano-Conglutination Technology.
Zhang, Man; Deng, Qiling; Xia, Liangping; Shi, Lifang; Cao, Axiu; Pang, Hui; Hu, Song
2015-09-01
Hollow nanospheres array is a special nanostructure with great applications in photonics, electronics and biochemistry. The nanofabrication technique with high resolution is crucial to nanosciences and nano-technology. This paper presents a novel nonconventional nano-conglutination technology combining polystyrenes spheres (PSs) self-assembly, conglutination and a lift-off process to fabricate the hollow nanospheres array with nanoholes. A self-assembly monolayer of PSs was stuck off from the quartz wafer by the thiol-ene adhesive material, and then the PSs was removed via a lift-off process and the hollow nanospheres embedded into the thiol-ene substrate was obtained. Thiolene polymer is a UV-curable material via "click chemistry" reaction at ambient conditions without the oxygen inhibition, which has excellent chemical and physical properties to be attractive as the adhesive material in nano-conglutination technology. Using the technique, a hollow nanospheres array with the nanoholes at the diameter of 200 nm embedded into the rigid thiol-ene substrate was fabricated, which has great potential to serve as a reaction container, catalyst and surface enhanced Raman scattering substrate.
NASA Technical Reports Server (NTRS)
Crabtree, W. L.
1980-01-01
A spectrophotovoltaic converter, a thermophotovoltaic converter, a cassegrainian concentrator, a large silicon cell blanket, and a high flux approach are among the concepts being investigated as part of the multihundred kW solar array program for reducing the cost of photovoltaic energy in space. These concepts involve a range of technology risks, the highest risk being represented by the thermophotovoltaics and spectrophotovoltaics approaches which involve manipulation to of the incoming spectrum to enhance system efficiency. The planar array (solar blanket) has no technology risk and a moderate payback. The primary characteristics, components, and technology concerns of each of these concepts are summarized. An orbital power platform mission in the late 1980's is being used to allow a coherent technology advancement program in order to achieve a ten year life with maintenance at a capital recurring cost of $30/watt based on 1978 dollars.
HER-2 as a Progression Factor and Therapeutic Target in Breast Cancer.
1999-06-01
used gene specific targeting of HER-2 with hammerhead - ribozyme expression constructs, a technology which we have applied successfully in the...2 in MCF-7 cells by ribozyme -targeting estradiol lost its ability to induce anchorage- independent colony formation in soft agar of the tumor cells...between estrogen and HER-2 signal transduction is ongoing. 14. SUBJECT TERMS Breast Cancer HER-2, estradiol, ribozymes , apoptosis, cell cycle, cDNA
NASA Astrophysics Data System (ADS)
Pongs, Guido; Bresseler, Bernd; Bergs, Thomas; Menke, Gert
2012-10-01
Today isothermal precision molding of imaging glass optics has become a widely applied and integrated production technology in the optical industry. Especially in consumer electronics (e.g. digital cameras, mobile phones, Blu-ray) a lot of optical systems contain rotationally symmetrical aspherical lenses produced by precision glass molding. But due to higher demands on complexity and miniaturization of optical elements the established process chain for precision glass molding is not sufficient enough. Wafer based molding processes for glass optics manufacturing become more and more interesting for mobile phone applications. Also cylindrical lens arrays can be used in high power laser systems. The usage of unsymmetrical free-form optics allows an increase of efficiency in optical laser systems. Aixtooling is working on different aspects in the fields of mold manufacturing technologies and molding processes for extremely high complex optical components. In terms of array molding technologies, Aixtooling has developed a manufacturing technology for the ultra-precision machining of carbide molds together with European partners. The development covers the machining of multi lens arrays as well as cylindrical lens arrays. The biggest challenge is the molding of complex free-form optics having no symmetrical axis. A comprehensive CAD/CAM data management along the entire process chain is essential to reach high accuracies on the molded lenses. Within a national funded project Aixtooling is working on a consistent data handling procedure in the process chain for precision molding of free-form optics.
Challenges and the state of the technology for printed sensor arrays for structural monitoring
NASA Astrophysics Data System (ADS)
Joshi, Shiv; Bland, Scott; DeMott, Robert; Anderson, Nickolas; Jursich, Gregory
2017-04-01
Printed sensor arrays are attractive for reliable, low-cost, and large-area mapping of structural systems. These sensor arrays can be printed on flexible substrates or directly on monitored structural parts. This technology is sought for continuous or on-demand real-time diagnosis and prognosis of complex structural components. In the past decade, many innovative technologies and functional materials have been explored to develop printed electronics and sensors. For example, an all-printed strain sensor array is a recent example of a low-cost, flexible and light-weight system that provides a reliable method for monitoring the state of aircraft structural parts. Among all-printing techniques, screen and inkjet printing methods are well suited for smaller-scale prototyping and have drawn much interest due to maturity of printing procedures and availability of compatible inks and substrates. Screen printing relies on a mask (screen) to transfer a pattern onto a substrate. Screen printing is widely used because of the high printing speed, large selection of ink/substrate materials, and capability of making complex multilayer devices. The complexity of collecting signals from a large number of sensors over a large area necessitates signal multiplexing electronics that need to be printed on flexible substrate or structure. As a result, these components are subjected to same deformation, temperature and other parameters for which sensor arrays are designed. The characteristics of these electronic components, such as transistors, are affected by deformation and other environmental parameters which can lead to erroneous sensed parameters. The manufacturing and functional challenges of the technology of printed sensor array systems for structural state monitoring are the focus of this presentation. Specific examples of strain sensor arrays will be presented to highlight the technical challenges.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Caberoy, Nora B.; Zhou, Yixiong; Alvarado, Gabriela
To efficiently elucidate the biological roles of phosphatidylserine (PS), we developed open-reading-frame (ORF) phage display to identify PS-binding proteins. The procedure of phage panning was optimized with a phage clone expressing MFG-E8, a well-known PS-binding protein. Three rounds of phage panning with ORF phage display cDNA library resulted in {approx}300-fold enrichment in PS-binding activity. A total of 17 PS-binding phage clones were identified. Unlike phage display with conventional cDNA libraries, all 17 PS-binding clones were ORFs encoding 13 real proteins. Sequence analysis revealed that all identified PS-specific phage clones had dimeric basic amino acid residues. GST fusion proteins were expressedmore » for 3 PS-binding proteins and verified for their binding activity to PS liposomes, but not phosphatidylcholine liposomes. These results elucidated previously unknown PS-binding proteins and demonstrated that ORF phage display is a versatile technology capable of efficiently identifying binding proteins for non-protein molecules like PS.« less
Amino acid sequence of a trypsin inhibitor from a Spirometra (Spirometra erinaceieuropaei).
Sanda, A; Uchida, A; Itagaki, T; Kobayashi, H; Inokuchi, N; Koyama, T; Iwama, M; Ohgi, K; Irie, M
2001-12-01
A trypsin inhibitor that is highly homologous with bovine pancreatic trypsin inhibitor (BPTI) was co-purified along with RNase from Spirometra (Spirometra erinaceieuropaei). The amino acid sequence of this inhibitor (SETI) and the nucleotide sequence of the cDNA encoding this protein were determined by protein chemistry and gene technology. SETI contains 68 amino acid residues and has a molecular mass of 7,798 Da. SETI has 31 amino acid residues that are identical with BPTI's sequence, including 6 half-cystine and 5 aromatic amino acid residues. The active site Lys residue in BPTI is replaced by an Arg residue in SETI. SETI is an effective inhibitor of trypsin and moderately inhibits a-chymotrypsin, but less inhibits elastase or subtilisin. SETI was expressed by E. coli containing a PelB vector carrying the SETI encoding cDNA; an expression yield of 0.68 mg/l was obtained. The phylogenetic relationship of SETI and the other BPTI-like trypsin inhibitors was analyzed using most likelihood inference methods.
Mojtahedi, Mitra; Fouquier d'Hérouël, Aymeric; Huang, Sui
2014-01-01
Digital PCR (dPCR) exploits limiting dilution of a template into an array of PCR reactions. From this array the number of reactions that contain at least one (as opposed to zero) initial template is determined, allowing inferring the original template concentration. Here we present a novel protocol to efficiently infer the concentration of a sample and its optimal dilution for dPCR from few targeted qPCR assays. By taking advantage of the real-time amplification feature of qPCR as opposed to relying on endpoint PCR assessment as in standard dPCR prior knowledge of template concentration is not necessary. This eliminates the need for serial dilutions in a separate titration and reduces the number of necessary reactions. We describe the theory underlying our approach and discuss experimental moments that contribute to uncertainty. We present data from a controlled experiment where the initial template concentration is known as proof of principle and apply our method on directly monitoring transcript level change during cell differentiation as well as gauging amplicon numbers in cDNA samples after pre-amplification. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.
Configuration study for a 30 GHz monolithic receive array: Technical assessment
NASA Technical Reports Server (NTRS)
Nester, W. H.; Cleaveland, B.; Edward, B.; Gotkis, S.; Hesserbacker, G.; Loh, J.; Mitchell, B.
1984-01-01
The current status of monolithic microwave integrated circuits (MMICs) in phased array feeds is discussed from the point of view of cost performance, reliability, and design considerations. Transitions to MMICs, compatible antenna radiating elements and reliability considerations are addressed. Hybrid antennas, feed array antenna technology, and offset reflectors versus phased arrays are examined.
Hook, Sharon E; Lampi, Mark A; Febbo, Eric J; Ward, Jeff A; Parkerton, Thomas F
2010-09-01
Time is often not characterized as a variable in ecotoxicogenomic studies. In this study, temporal changes in gene expression were determined during exposure to crude oil and a subsequent recovery period. Juvenile rainbow trout, Oncorhynchus mykiss, were exposed for 96 h to the water accommodated fractions of 0.4, 2 or 10 mgl(-1) crude oil loadings. Following 96 h of exposure, fish were transferred to recovery tanks. Gill and liver samples were collected after 24 and 96 h of exposure, and after 96 h of recovery for RNA extraction and microarray analysis. Fluorescently labeled cDNA was hybridized against matched controls, using salmonid cDNA arrays. Each exposure scenario generated unique patterns of altered gene expression. More genes responded to crude oil in the gill than in the liver. In the gill, 1137 genes had altered expression at 24 h, 2003 genes had altered expression levels at 96 h of exposure, yet by 96 h of recovery, no genes were significantly altered in expression. In the liver at 10 mgl(-1), only five genes were changed at 24 h, yet 192 genes had altered expression after 96 h recovery. At 2 mgl(-1) in the liver, many genes had altered regulation at all three time points. The 0.4 mgl(-1) loading also showed 289 genes upregulated at 24 h after exposure. The Gene Ontology terms associated with altered expression in the liver suggested that the processes of protein synthesis, xenobiotic metabolism, and oxidoreductase activity were altered. The concentration-responsive expression profile of cytochrome P450 1A, a biomarker for oil exposure, did not predict the majority of gene expression profiles in any tissue or dose, since direct relationships with dose were not observed for most genes. While the genes and their associated functions agree with known modes of toxic action for crude oil, the gene lists obtained do not match our previously published work, presumably due to array analysis procedures. These results demonstrate that changes in gene expression with time and dose may be complicated, and should be characterized in controlled laboratory settings before attempts are made to interpret responses in field-collected organisms. Further, processes for analyzing microarray data need to be developed such that standardized gene lists are developed, or that analysis does not rely on lists of significantly altered genes before arrays can be further evaluated as a monitoring tool. Crown Copyright 2010. Published by Elsevier B.V. All rights reserved.
Isolation and characterization of cDNA clones for carrot extensin and a proline-rich 33-kDa protein
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, J.; Varner, J.E.
1985-07-01
Extensins are hydroxyproline-rich glycoproteins associated with most dicotyledonous plant cell walls. To isolate cDNA clones encoding extensin, the authors started by isolating poly(A) RNA from carrot root tissue, and then translating the RNA in vitro, in the presence of tritiated leucine or proline. A 33-kDa peptide was identified in the translation products as a putative extensin precursor. From a cDNA library constructed with poly(A) RNA from wounded carrots, one cDNA clone (pDC5) was identified that specifically hybridized to poly(A) RNA encoding this 33-kDa peptide. They isolated three cDNA clones (pDC11, pDC12, and pDC16) from another cDNA library using pCD5 asmore » a probe. DNA sequence data, RNA hybridization analysis, and hybrid released in vitro translation indicate that the cDNA clones pDC11 encodes extensin and that cDNA clones pDC12 and pDC16 encode the 33-kDa peptide, which as yet has an unknown identity and function. The assumption that the 33-kDa peptide was an extensin precursor was invalid. RNA hybridization analysis showed that RNA encoded by both clone types is accumulated upon wounding.« less
RICD: a rice indica cDNA database resource for rice functional genomics.
Lu, Tingting; Huang, Xuehui; Zhu, Chuanrang; Huang, Tao; Zhao, Qiang; Xie, Kabing; Xiong, Lizhong; Zhang, Qifa; Han, Bin
2008-11-26
The Oryza sativa L. indica subspecies is the most widely cultivated rice. During the last few years, we have collected over 20,000 putative full-length cDNAs and over 40,000 ESTs isolated from various cDNA libraries of two indica varieties Guangluai 4 and Minghui 63. A database of the rice indica cDNAs was therefore built to provide a comprehensive web data source for searching and retrieving the indica cDNA clones. Rice Indica cDNA Database (RICD) is an online MySQL-PHP driven database with a user-friendly web interface. It allows investigators to query the cDNA clones by keyword, genome position, nucleotide or protein sequence, and putative function. It also provides a series of information, including sequences, protein domain annotations, similarity search results, SNPs and InDels information, and hyperlinks to gene annotation in both The Rice Annotation Project Database (RAP-DB) and The TIGR Rice Genome Annotation Resource, expression atlas in RiceGE and variation report in Gramene of each cDNA. The online rice indica cDNA database provides cDNA resource with comprehensive information to researchers for functional analysis of indica subspecies and for comparative genomics. The RICD database is available through our website http://www.ncgr.ac.cn/ricd.
Status of LWIR HgCdTe infrared detector technology
NASA Technical Reports Server (NTRS)
Reine, M. B.
1990-01-01
The performance requirements that today's advanced Long Wavelength Infrared (LWIR) focal plane arrays place on the HgCdTe photovoltaic detector array are summarized. The theoretical performance limits for intrinsic LWIR HgCdTe detectors are reviewed as functions of cutoff wavelength and operating temperature. The status of LWIR HgCdTe photovoltaic detectors is reviewed and compared to the focal plane array (FPA) requirements and to the theoretical limits. Emphasis is placed on recent data for two-layer HgCdTe PLE heterojunction photodiodes grown at Loral with cutoff wavelengths ranging between 10 and 19 microns at temperatures of 70 to 80 K. Development trends in LWIR HgCdTe detector technology are outlined, and conclusions are drawn about the ability for photovoltaic HgCdTe detector arrays to satisfy a wide variety of advanced FPA array applications.
Method for construction of normalized cDNA libraries
Soares, Marcelo B.; Efstratiadis, Argiris
1998-01-01
This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form comprising: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3' noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to appropriate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library. This invention also provides normalized cDNA libraries generated by the above-described method and uses of the generated libraries.
Method for construction of normalized cDNA libraries
Soares, M.B.; Efstratiadis, A.
1998-11-03
This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form comprising: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3` noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to appropriate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library. This invention also provides normalized cDNA libraries generated by the above-described method and uses of the generated libraries. 19 figs.
Infrared sensors for Earth observation missions
NASA Astrophysics Data System (ADS)
Ashcroft, P.; Thorne, P.; Weller, H.; Baker, I.
2007-10-01
SELEX S&AS is developing a family of infrared sensors for earth observation missions. The spectral bands cover shortwave infrared (SWIR) channels from around 1μm to long-wave infrared (LWIR) channels up to 15μm. Our mercury cadmium telluride (MCT) technology has enabled a sensor array design that can satisfy the requirements of all of the SWIR and medium-wave infrared (MWIR) bands with near-identical arrays. This is made possible by the combination of a set of existing technologies that together enable a high degree of flexibility in the pixel geometry, sensitivity, and photocurrent integration capacity. The solution employs a photodiode array under the control of a readout integrated circuit (ROIC). The ROIC allows flexible geometries and in-pixel redundancy to maximise operability and reliability, by combining the photocurrent from a number of photodiodes into a single pixel. Defective or inoperable diodes (or "sub-pixels") can be deselected with tolerable impact on the overall pixel performance. The arrays will be fabricated using the "loophole" process in MCT grown by liquid-phase epitaxy (LPE). These arrays are inherently robust, offer high quantum efficiencies and have been used in previous space programs. The use of loophole arrays also offers access to SELEX's avalanche photodiode (APD) technology, allowing low-noise, highly uniform gain at the pixel level where photon flux is very low.
Carbonetti, Sara; Oliver, Brian G; Vigdorovich, Vladimir; Dambrauskas, Nicholas; Sack, Brandon; Bergl, Emilee; Kappe, Stefan H I; Sather, D Noah
2017-09-01
Monoclonal antibody technologies have enabled dramatic advances in immunology, the study of infectious disease, and modern medicine over the past 40years. However, many monoclonal antibody discovery procedures are labor- and time-intensive, low efficiency, and expensive. Here we describe an optimized mAb discovery platform for the rapid and efficient isolation, cloning and characterization of monoclonal antibodies in murine systems. In this platform, antigen-binding splenic B cells from immunized mice are isolated by FACS and cocultured with CD40L positive cells to induce proliferation and mAb production. After 12days of coculture, cell culture supernatants are screened for antigen, and IgG positivity and RNA is isolated for reverse-transcription. Positive-well cDNA is then amplified by PCR and the resulting amplicons can be cloned into ligation-independent expression vectors, which are then used directly to transfect HEK293 cells for recombinant antibody production. After 4days of growth, conditioned medium can be screened using biolayer interferometry for antigen binding and affinity measurements. Using this method, we were able to isolate six unique, functional monoclonal antibodies against an antigen of the human malaria parasite Plasmodium falciparum. Importantly, this method incorporates several important advances that circumvent the need for single-cell PCR, restriction cloning, and large scale protein production, and can be applied to a wide array of protein antigens. Copyright © 2017 Elsevier B.V. All rights reserved.
Travis, G H; Sutcliffe, J G
1988-01-01
To isolate cDNA clones of low-abundance mRNAs expressed in monkey cerebral cortex but absent from cerebellum, we developed an improved subtractive cDNA cloning procedure that requires only modest quantities of mRNA. Plasmid DNA from a monkey cerebellum cDNA library was hybridized in large excess to radiolabeled monkey cortex cDNA in a phenol emulsion-enhanced reaction. The unhybridized cortex cDNA was isolated by chromatography on hydroxyapatite and used to probe colonies from a monkey cortex cDNA library. Of 60,000 colonies screened, 163 clones were isolated and confirmed by colony hybridization or RNA blotting to represent mRNAs, ranging from 0.001% to 0.1% abundance, specific to or highly enriched in cerebral cortex relative to cerebellum. Clones of one medium-abundance mRNA were recovered almost quantitatively. Two of the lower-abundance mRNAs were expressed at levels reduced by a factor of 10 in Alzheimer disease relative to normal human cortex. One of these was identified as the monkey preprosomatostatin I mRNA. Images PMID:2894033
Xu, De-Quan; Zhang, Yi-Bing; Xiong, Yuan-Zhu; Gui, Jian-Fang; Jiang, Si-Wen; Su, Yu-Hong
2003-07-01
Using suppression subtractive hybridization (SSH) technique, forward and reverse subtracted cDNA libraries were constructed between Longissimus muscles from Meishan and Landrace pigs. A housekeeping gene, G3PDH, was used to estimate the efficiency of subtractive cDNA. In two cDNA libraries, G3PDH was subtracted very efficiently at appropriate 2(10) and 2(5) folds, respectively, indicating that some differentially expressed genes were also enriched at the same folds and the two subtractive cDNA libraries were very successful. A total of 709 and 673 positive clones were isolated from forward and reverse subtracted cDNA libraries, respectively. Analysis of PCR showed that most of all plasmids in the clones contained 150-750 bp inserts. The construction of subtractive cDNA libraries between muscle tissue from different pig breeds laid solid foundations for isolating and identifying the genes determining muscle growth and meat quality, which will be important to understand the mechanism of muscle growth, determination of meat quality and practice of molecular breeding.
Hu, Lin-Yong; Cui, Chen-Chen; Song, Yu-Jie; Wang, Xiang-Guo; Jin, Ya-Ping; Wang, Ai-Hua; Zhang, Yong
2012-07-01
cDNA is widely used in gene function elucidation and/or transgenics research but often suitable tissues or cells from which to isolate mRNA for reverse transcription are unavailable. Here, an alternative method for cDNA cloning is described and tested by cloning the cDNA of human LALBA (human alpha-lactalbumin) from genomic DNA. First, genomic DNA containing all of the coding exons was cloned from human peripheral blood and inserted into a eukaryotic expression vector. Next, by delivering the plasmids into either 293T or fibroblast cells, surrogate cells were constructed. Finally, the total RNA was extracted from the surrogate cells and cDNA was obtained by RT-PCR. The human LALBA cDNA that was obtained was compared with the corresponding mRNA published in GenBank. The comparison showed that the two sequences were identical. The novel method for cDNA cloning from surrogate eukaryotic cells described here uses well-established techniques that are feasible and simple to use. We anticipate that this alternative method will have widespread applications.
LEDGF/p75 Deficiency Increases Deletions at the HIV-1 cDNA Ends.
Bueno, Murilo T D; Reyes, Daniel; Llano, Manuel
2017-09-15
Processing of unintegrated linear HIV-1 cDNA by the host DNA repair system results in its degradation and/or circularization. As a consequence, deficient viral cDNA integration generally leads to an increase in the levels of HIV-1 cDNA circles containing one or two long terminal repeats (LTRs). Intriguingly, impaired HIV-1 integration in LEDGF/p75-deficient cells does not result in a correspondent increase in viral cDNA circles. We postulate that increased degradation of unintegrated linear viral cDNA in cells lacking the lens epithelium-derived growth factor (LEDGF/p75) account for this inconsistency. To evaluate this hypothesis, we characterized the nucleotide sequence spanning 2-LTR junctions isolated from LEDGF/p75-deficient and control cells. LEDGF/p75 deficiency resulted in a significant increase in the frequency of 2-LTRs harboring large deletions. Of note, these deletions were dependent on the 3' processing activity of integrase and were not originated by aberrant reverse transcription. Our findings suggest a novel role of LEDGF/p75 in protecting the unintegrated 3' processed linear HIV-1 cDNA from exonucleolytic degradation.
Trujillo-Esquivel, Elías; Franco, Bernardo; Flores-Martínez, Alberto; Ponce-Noyola, Patricia; Mora-Montes, Héctor M
2016-08-02
Analysis of gene expression is a common research tool to study networks controlling gene expression, the role of genes with unknown function, and environmentally induced responses of organisms. Most of the analytical tools used to analyze gene expression rely on accurate cDNA synthesis and quantification to obtain reproducible and quantifiable results. Thus far, most commercial kits for isolation and purification of cDNA target double-stranded molecules, which do not accurately represent the abundance of transcripts. In the present report, we provide a simple and fast method to purify single-stranded cDNA, exhibiting high purity and yield. This method is based on the treatment with RNase H and RNase A after cDNA synthesis, followed by separation in silica spin-columns and ethanol precipitation. In addition, our method avoids the use of DNase I to eliminate genomic DNA from RNA preparations, which improves cDNA yield. As a case report, our method proved to be useful in the purification of single-stranded cDNA from the pathogenic fungus Sporothrix schenckii.
Construction of Infectious cDNA Clone of a Chrysanthemum stunt viroid Korean Isolate
Yoon, Ju-Yeon; Cho, In-Sook; Choi, Gug-Seoun; Choi, Seung-Kook
2014-01-01
Chrysanthemum stunt viroid (CSVd), a noncoding infectious RNA molecule, causes seriously economic losses of chrysanthemum for 3 or 4 years after its first infection. Monomeric cDNA clones of CSVd isolate SK1 (CSVd-SK1) were constructed in the plasmids pGEM-T easy vector and pUC19 vector. Linear positive-sense transcripts synthesized in vitro from the full-length monomeric cDNA clones of CSVd-SK1 could infect systemically tomato seedlings and chrysanthemum plants, suggesting that the linear CSVd RNA transcribed from the cDNA clones could be replicated as efficiently as circular CSVd in host species. However, direct inoculation of plasmid cDNA clones containing full-length monomeric cDNA of CSVd-SK1 failed to infect tomato and chrysanthemum and linear negative-sense transcripts from the plasmid DNAs were not infectious in the two plant species. The cDNA sequences of progeny viroid in systemically infected tomato and chrysanthemum showed a few substitutions at a specific nucleotide position, but there were no deletions and insertions in the sequences of the CSVd progeny from tomato and chrysanthemum plants. PMID:25288987
Evaluation of vector-primed cDNA library production from microgram quantities of total RNA.
Kuo, Jonathan; Inman, Jason; Brownstein, Michael; Usdin, Ted B
2004-12-15
cDNA sequences are important for defining the coding region of genes, and full-length cDNA clones have proven to be useful for investigation of the function of gene products. We produced cDNA libraries containing 3.5-5 x 10(5) primary transformants, starting with 5 mug of total RNA prepared from mouse pituitary, adrenal, thymus, and pineal tissue, using a vector-primed cDNA synthesis method. Of approximately 1000 clones sequenced, approximately 20% contained the full open reading frames (ORFs) of known transcripts, based on the presence of the initiating methionine residue codon. The libraries were complex, with 94, 91, 83 and 55% of the clones from the thymus, adrenal, pineal and pituitary libraries, respectively, represented only once. Twenty-five full-length clones, not yet represented in the Mammalian Gene Collection, were identified. Thus, we have produced useful cDNA libraries for the isolation of full-length cDNA clones that are not yet available in the public domain, and demonstrated the utility of a simple method for making high-quality libraries from small amounts of starting material.
USDA-ARS?s Scientific Manuscript database
Carrot is one of the most economically important vegetables worldwide, however, genetic and genomic resources supporting carrot breeding remain limited. We developed a Diversity Arrays Technology (DArT) platform for wild and cultivated carrot and used it to investigate genetic diversity and to devel...
Comparison of next generation sequencing technologies for transcriptome characterization
2009-01-01
Background We have developed a simulation approach to help determine the optimal mixture of sequencing methods for most complete and cost effective transcriptome sequencing. We compared simulation results for traditional capillary sequencing with "Next Generation" (NG) ultra high-throughput technologies. The simulation model was parameterized using mappings of 130,000 cDNA sequence reads to the Arabidopsis genome (NCBI Accession SRA008180.19). We also generated 454-GS20 sequences and de novo assemblies for the basal eudicot California poppy (Eschscholzia californica) and the magnoliid avocado (Persea americana) using a variety of methods for cDNA synthesis. Results The Arabidopsis reads tagged more than 15,000 genes, including new splice variants and extended UTR regions. Of the total 134,791 reads (13.8 MB), 119,518 (88.7%) mapped exactly to known exons, while 1,117 (0.8%) mapped to introns, 11,524 (8.6%) spanned annotated intron/exon boundaries, and 3,066 (2.3%) extended beyond the end of annotated UTRs. Sequence-based inference of relative gene expression levels correlated significantly with microarray data. As expected, NG sequencing of normalized libraries tagged more genes than non-normalized libraries, although non-normalized libraries yielded more full-length cDNA sequences. The Arabidopsis data were used to simulate additional rounds of NG and traditional EST sequencing, and various combinations of each. Our simulations suggest a combination of FLX and Solexa sequencing for optimal transcriptome coverage at modest cost. We have also developed ESTcalc http://fgp.huck.psu.edu/NG_Sims/ngsim.pl, an online webtool, which allows users to explore the results of this study by specifying individualized costs and sequencing characteristics. Conclusion NG sequencing technologies are a highly flexible set of platforms that can be scaled to suit different project goals. In terms of sequence coverage alone, the NG sequencing is a dramatic advance over capillary-based sequencing, but NG sequencing also presents significant challenges in assembly and sequence accuracy due to short read lengths, method-specific sequencing errors, and the absence of physical clones. These problems may be overcome by hybrid sequencing strategies using a mixture of sequencing methodologies, by new assemblers, and by sequencing more deeply. Sequencing and microarray outcomes from multiple experiments suggest that our simulator will be useful for guiding NG transcriptome sequencing projects in a wide range of organisms. PMID:19646272
Progress on uncooled PbSe detectors for low-cost applications
NASA Astrophysics Data System (ADS)
Vergara, German; Gomez, Luis J.; Villamayor, Victor; Alvarez, M.; Rodrigo, Maria T.; del Carmen Torquemada, Maria; Sanchez, Fernando J.; Verdu, Marina; Diezhandino, Jorge; Rodriguez, Purificacion; Catalan, Irene; Almazan, Rosa; Plaza, Julio; Montojo, Maria T.
2004-08-01
This work reports on progress on development of polycrystalline PbSe infrared detectors at the Centro de Investigacion y Desarrollo de la Armada (CIDA). Since mid nineties, the CIDA owns an innovative technology for processing uncooled MWIR detectors of polycrystalline PbSe. Based on this technology, some applications have been developed. However, future applications demand smarter, more complex, faster yet cheaper detectors. Aiming to open new perspectives to polycrystalline PbSe detectors, we are currently working on different directions: 1) Processing of 2D arrays: a) Designing and processing low density x-y addressed arrays with 16x16 and 32x32 elements, as an extension of our standard technology. b) Trying to make compatible standard CMOS and polycrystalline PbSe technologies in order to process monolithic large format arrays. 2) Adding new features to the detector such as monolithically integrated spectral discrimination.
Study of large adaptive arrays for space technology applications
NASA Technical Reports Server (NTRS)
Berkowitz, R. S.; Steinberg, B.; Powers, E.; Lim, T.
1977-01-01
The research in large adaptive antenna arrays for space technology applications is reported. Specifically two tasks were considered. The first was a system design study for accurate determination of the positions and the frequencies of sources radiating from the earth's surface that could be used for the rapid location of people or vehicles in distress. This system design study led to a nonrigid array about 8 km in size with means for locating the array element positions, receiving signals from the earth and determining the source locations and frequencies of the transmitting sources. It is concluded that this system design is feasible, and satisfies the desired objectives. The second task was an experiment to determine the largest earthbound array which could simulate a spaceborne experiment. It was determined that an 800 ft array would perform indistinguishably in both locations and it is estimated that one several times larger also would serve satisfactorily. In addition the power density spectrum of the phase difference fluctuations across a large array was measured. It was found that the spectrum falls off approximately as f to the minus 5/2 power.
High Contrast Programmable Field Masks for JWST NIRSpec
NASA Technical Reports Server (NTRS)
Kutyrev, Alexander S.
2008-01-01
Microshutter arrays are one of the novel technologies developed for the James Webb Space Telescope (JWST). It will allow Near Infrared Spectrometer (NIRSpec) to acquire spectra of hundreds of objects simultaneously therefore increasing its efficiency tremendously. We have developed these programmable arrays that are based on Micro-Electro Mechanical Structures (MEMS) technology. The arrays are 2D addressable masks that can operate in cryogenic environment of JWST. Since the primary JWST science requires acquisition of spectra of extremely faint objects, it is important to provide very high contrast of the open to closed shutters. This high contrast is necessary to eliminate any possible contamination and confusion in the acquired spectra by unwanted objects. We have developed and built a test system for the microshutter array functional and optical characterization. This system is capable of measuring the contrast of the microshutter array both in visible and infrared light of the NIRSpec wavelength range while the arrays are in their working cryogenic environment. We have measured contrast ratio of several microshutter arrays and demonstrated that they satisfy and in many cases far exceed the NIRSpec contrast requirement value of 2000.
Bidlingmaier, Scott; Ha, Kevin; Lee, Nam-Kyung; Su, Yang; Liu, Bin
2016-04-01
Although the bioactive sphingolipid ceramide is an important cell signaling molecule, relatively few direct ceramide-interacting proteins are known. We used an approach combining yeast surface cDNA display and deep sequencing technology to identify novel proteins binding directly to ceramide. We identified 234 candidate ceramide-binding protein fragments and validated binding for 20. Most (17) bound selectively to ceramide, although a few (3) bound to other lipids as well. Several novel ceramide-binding domains were discovered, including the EF-hand calcium-binding motif, the heat shock chaperonin-binding motif STI1, the SCP2 sterol-binding domain, and the tetratricopeptide repeat region motif. Interestingly, four of the verified ceramide-binding proteins (HPCA, HPCAL1, NCS1, and VSNL1) and an additional three candidate ceramide-binding proteins (NCALD, HPCAL4, and KCNIP3) belong to the neuronal calcium sensor family of EF hand-containing proteins. We used mutagenesis to map the ceramide-binding site in HPCA and to create a mutant HPCA that does not bind to ceramide. We demonstrated selective binding to ceramide by mammalian cell-produced wild type but not mutant HPCA. Intriguingly, we also identified a fragment from prostaglandin D2synthase that binds preferentially to ceramide 1-phosphate. The wide variety of proteins and domains capable of binding to ceramide suggests that many of the signaling functions of ceramide may be regulated by direct binding to these proteins. Based on the deep sequencing data, we estimate that our yeast surface cDNA display library covers ∼60% of the human proteome and our selection/deep sequencing protocol can identify target-interacting protein fragments that are present at extremely low frequency in the starting library. Thus, the yeast surface cDNA display/deep sequencing approach is a rapid, comprehensive, and flexible method for the analysis of protein-ligand interactions, particularly for the study of non-protein ligands. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.
Wang, Hai-Tao; Kong, Jian-Ping; Ding, Fang; Wang, Xiu-Qin; Wang, Ming-Rong; Liu, Lian-Xin; Wu, Min; Liu, Zhi-Hua
2003-01-01
AIM: To obtain human esophageal cancer cell EC9706 stably expressed epithelial membrane protein-1 (EMP-1) with integrated eukaryotic plasmid harboring the open reading frame (ORF) of human EMP-1, and then to study the mechanism by which EMP-1 exerts its diverse cellular action on cell proliferation and altered gene profile by exploring the effect of EMP-1. METHODS: The authors first constructed pcDNA3.1/myc-his expression vector harboring the ORF of EMP-1 and then transfected it into human esophageal carcinoma cell line EC9706. The positive clones were analyzed by Western blot and RT-PCR. Moreover, the cell growth curve was observed and the cell cycle was checked by FACS technique. Using cDNA microarray technology, the authors compared the gene expression pattern in positive clones with control. To confirm the gene expression profile, semi-quantitative RT-PCR was carried out for 4 of the randomly picked differentially expressed genes. For those differentially expressed genes, classification was performed according to their function and cellular component. RESULTS: Human EMP-1 gene can be stably expressed in EC9706 cell line transfected with human EMP-1. The authors found the cell growth decreased, among which S phase was arrested and G1 phase was prolonged in the transfected positive clones. By cDNA microarray analysis, 35 genes showed an over 2.0 fold change in expression level after transfection, with 28 genes being consistently up-regulated and 7 genes being down-regulated. Among the classified genes, almost half of the induced genes (13 out of 28 genes) were related to cell signaling, cell communication and particularly to adhesion. CONCLUSION: Overexpression of human EMP-1 gene can inhibit the proliferation of EC9706 cell with S phase arrested and G1 phase prolonged. The cDNA microarray analysis suggested that EMP-1 may be one of regulators involved in cell signaling, cell communication and adhesion regulators. PMID:12632483
Wang, Hai-Tao; Kong, Jian-Ping; Ding, Fang; Wang, Xiu-Qin; Wang, Ming-Rong; Liu, Lian-Xin; Wu, Min; Liu, Zhi-Hua
2003-03-01
To obtain human esophageal cancer cell EC9706 stably expressed epithelial membrane protein-1 (EMP-1) with integrated eukaryotic plasmid harboring the open reading frame (ORF) of human EMP-1, and then to study the mechanism by which EMP-1 exerts its diverse cellular action on cell proliferation and altered gene profile by exploring the effect of EMP-1. The authors first constructed pcDNA3.1/myc-his expression vector harboring the ORF of EMP-1 and then transfected it into human esophageal carcinoma cell line EC9706. The positive clones were analyzed by Western blot and RT-PCR. Moreover, the cell growth curve was observed and the cell cycle was checked by FACS technique. Using cDNA microarray technology, the authors compared the gene expression pattern in positive clones with control. To confirm the gene expression profile, semi-quantitative RT-PCR was carried out for 4 of the randomly picked differentially expressed genes. For those differentially expressed genes, classification was performed according to their function and cellular component. Human EMP-1 gene can be stably expressed in EC9706 cell line transfected with human EMP-1. The authors found the cell growth decreased, among which S phase was arrested and G1 phase was prolonged in the transfected positive clones. By cDNA microarray analysis, 35 genes showed an over 2.0 fold change in expression level after transfection, with 28 genes being consistently up-regulated and 7 genes being down-regulated. Among the classified genes, almost half of the induced genes (13 out of 28 genes) were related to cell signaling, cell communication and particularly to adhesion. Overexpression of human EMP-1 gene can inhibit the proliferation of EC9706 cell with S phase arrested and G1 phase prolonged. The cDNA microarray analysis suggested that EMP-1 may be one of regulators involved in cell signaling, cell communication and adhesion regulators.
Liu, Zhong-Yu; Yu, Jiu-Yang; Huang, Xing-Yao; Fan, Hang; Li, Xiao-Feng; Deng, Yong-Qiang; Ji, Xue; Cheng, Meng-Li; Ye, Qing; Zhao, Hui; Han, Jian-Feng; An, Xiao-Ping; Jiang, Tao; Zhang, Bo; Tong, Yi-Gang; Qin, Cheng-Feng
2017-11-01
Zika virus (ZIKV) has caused significant outbreaks and epidemics in the Americas recently, raising global concern due to its ability to cause microcephaly and other neurological complications. A stable and efficient infectious clone of ZIKV is urgently needed. However, the instability and toxicity of flavivirus cDNA clones in Escherichia coli hosts has hindered the development of ZIKV infectious clones. Here, using a novel self-splicing ribozyme-based strategy, we generated a stable infectious cDNA clone of a contemporary ZIKV strain imported from Venezuela to China in 2016. The constructed clone contained a modified version of the group II self-splicing intron P.li.LSUI2 near the junction between the E and NS1 genes, which were removed from the RNA transcripts by an easy-to-establish in vitro splicing reaction. Transfection of the spliced RNAs into BHK-21 cells led to the production of infectious progeny virus that resembled the parental virus. Finally, potential cis -acting RNA elements in ZIKV genomic RNA were identified based on this novel reverse genetics system, and the critical role of 5'-SLA promoter and 5'-3' cyclization sequences were characterized by a combination of different assays. Our results provide another stable and reliable reverse genetics system for ZIKV that will help study ZIKV infection and pathogenesis, and the novel self-splicing intron-based strategy could be further expanded for the construction of infectious clones from other emerging and reemerging flaviviruses. IMPORTANCE The ongoing Zika virus (ZIKV) outbreaks have drawn global concern due to the unexpected causal link to fetus microcephaly and other severe neurological complications. The infectious cDNA clones of ZIKV are critical for the research community to study the virus, understand the disease, and inform vaccine design and antiviral screening. A panel of existing technologies have been utilized to develop ZIKV infectious clones. Here, we successfully generated a stable infectious clone of a 2016 ZIKV strain using a novel self-splicing ribozyme-based technology that abolished the potential toxicity of ZIKV cDNA clones to the E. coli host. Moreover, two crucial cis -acting replication elements (5'-SLA and 5'-CS) of ZIKV were first identified using this novel reverse genetics system. This novel self-splicing ribozyme-based reverse genetics platform will be widely utilized in future ZIKV studies and provide insight for the development of infectious clones of other emerging viruses. Copyright © 2017 American Society for Microbiology.
Liu, Zhong-Yu; Yu, Jiu-Yang; Huang, Xing-Yao; Fan, Hang; Li, Xiao-Feng; Deng, Yong-Qiang; Ji, Xue; Cheng, Meng-Li; Ye, Qing; Zhao, Hui; Han, Jian-Feng; An, Xiao-Ping; Jiang, Tao; Zhang, Bo; Tong, Yi-Gang
2017-01-01
ABSTRACT Zika virus (ZIKV) has caused significant outbreaks and epidemics in the Americas recently, raising global concern due to its ability to cause microcephaly and other neurological complications. A stable and efficient infectious clone of ZIKV is urgently needed. However, the instability and toxicity of flavivirus cDNA clones in Escherichia coli hosts has hindered the development of ZIKV infectious clones. Here, using a novel self-splicing ribozyme-based strategy, we generated a stable infectious cDNA clone of a contemporary ZIKV strain imported from Venezuela to China in 2016. The constructed clone contained a modified version of the group II self-splicing intron P.li.LSUI2 near the junction between the E and NS1 genes, which were removed from the RNA transcripts by an easy-to-establish in vitro splicing reaction. Transfection of the spliced RNAs into BHK-21 cells led to the production of infectious progeny virus that resembled the parental virus. Finally, potential cis-acting RNA elements in ZIKV genomic RNA were identified based on this novel reverse genetics system, and the critical role of 5′-SLA promoter and 5′-3′ cyclization sequences were characterized by a combination of different assays. Our results provide another stable and reliable reverse genetics system for ZIKV that will help study ZIKV infection and pathogenesis, and the novel self-splicing intron-based strategy could be further expanded for the construction of infectious clones from other emerging and reemerging flaviviruses. IMPORTANCE The ongoing Zika virus (ZIKV) outbreaks have drawn global concern due to the unexpected causal link to fetus microcephaly and other severe neurological complications. The infectious cDNA clones of ZIKV are critical for the research community to study the virus, understand the disease, and inform vaccine design and antiviral screening. A panel of existing technologies have been utilized to develop ZIKV infectious clones. Here, we successfully generated a stable infectious clone of a 2016 ZIKV strain using a novel self-splicing ribozyme-based technology that abolished the potential toxicity of ZIKV cDNA clones to the E. coli host. Moreover, two crucial cis-acting replication elements (5′-SLA and 5′-CS) of ZIKV were first identified using this novel reverse genetics system. This novel self-splicing ribozyme-based reverse genetics platform will be widely utilized in future ZIKV studies and provide insight for the development of infectious clones of other emerging viruses. PMID:28814522
Progress and prospects of silicon-based design for optical phased array
NASA Astrophysics Data System (ADS)
Hu, Weiwei; Peng, Chao; Chang-Hasnain, Connie
2016-03-01
The high-speed, high-efficient, compact phase modulator array is indispensable in the Optical-phased array (OPA) which has been considered as a promising technology for realizing flexible and efficient beam steering. In our research, two methods are presented to utilize high-contrast grating (HCG) as high-efficient phase modulator. One is that HCG possesses high-Q resonances that origins from the cancellation of leaky waves. As a result, sharp resonance peaks appear on the reflection spectrum thus HCGs can be utilized as efficient phase shifters. Another is that low-Q mode HCG is utilized as ultra-lightweight mirror. With MEMS technology, small HCG displacement (~50 nm) leads to large phase change (~1.7π). Effective beam steering is achieved in Connie Chang-Hasnian's group. On the other hand, we theoretically and experimentally investigate the system design for silicon-based optical phased array, including the star coupler, phased array, emission elements and far-field patterns. Further, the non-uniform optical phased array is presented.
Earth Science Geostationary Platform Technology
NASA Technical Reports Server (NTRS)
Wright, Robert L. (Editor); Campbell, Thomas G. (Editor)
1989-01-01
The objective of the workshop was to address problems in science and in four technology areas (large space antenna technology, microwave sensor technology, electromagnetics-phased array adaptive systems technology, and optical metrology technology) related to Earth Science Geostationary Platform missions.
Phased Arrays of Ground and Airborne Mobile Terminals for Satellite Communications
NASA Technical Reports Server (NTRS)
Huang, John
1996-01-01
Phased array antenna is beginning to play an important in the arena of mobile/satellite communications. Two examples of mobile terminal phased arrays will be shown. Their technical background, challenges, and cost drivers will be discussed. A possible solution to combat some of the deficiencies of the conventional phased array by exploiting the phased reflectarray technology will be briefly presented.
NASA Astrophysics Data System (ADS)
Duparré, Jacques; Wippermann, Frank; Dannberg, Peter; Schreiber, Peter; Bräuer, Andreas; Völkel, Reinhard; Scharf, Toralf
2005-09-01
Two novel objective types on the basis of artificial compound eyes are examined. Both imaging systems are well suited for fabrication using microoptics technology due to the small required lens sags. In the apposition optics a microlens array (MLA) and a photo detector array of different pitch in its focal plane are applied. The image reconstruction is based on moire magnification. Several generations of demonstrators of this objective type are manufactured by photo lithographic processes. This includes a system with opaque walls between adjacent channels and an objective which is directly applied onto a CMOS detector array. The cluster eye approach, which is based on a mixture of superposition compound eyes and the vision system of jumping spiders, produces a regular image. Here, three microlens arrays of different pitch form arrays of Keplerian microtelescopes with tilted optical axes, including a field lens. The microlens arrays of this demonstrator are also fabricated using microoptics technology, aperture arrays are applied. Subsequently the lens arrays are stacked to the overall microoptical system on wafer scale. Both fabricated types of artificial compound eye imaging systems are experimentally characterized with respect to resolution, sensitivity and cross talk between adjacent channels. Captured images are presented.
Two color QWIP and extended wavebands
NASA Astrophysics Data System (ADS)
Costard, Eric; Truffer, Jean P.; Huet, Odile; Dua, Lydie; Nedelcu, Alexandru; Robo, J. A.; Marcadet, Xavier; Briere de l'Isle, Nadia; Bois, Philippe; Manissadjian, A.; Gohier, D.
2007-04-01
Since 2002, the THALES Group has been manufacturing sensitive arrays using QWIP technology based on GaAs and related III-V compounds, at THALES Research and Technology Laboratory. The QWIP technology allows the realization of large staring arrays for Thermal Imagers (TI) working in the long-wave infrared (LWIR) band (8-12 μm). In the past researchers claimed many advantages of QWIPs. Uniformity was one of these and has been the key parameter for the production to start. The 640x512 LWIR focal plane arrays (FPAs) with 20μm pitch was the demonstration that state of the art performances can be achieved even with small pixels. This opened the field for the realization of usable and affordable megapixel FPAs. Thales Research & Technology (TRT) has been developing third generation GaAs LWIR QWIP arrays for volume manufacture of high performance low cost thermal imaging cameras. In the past, another widely claimed advantage for QWIPs was the so-called band-gap engineering and versatility of the III-V processing allowing the custom design of quantum structures to fulfil the requirements of specific applications such as very long wavelength (VLWIR) or multispectral detection. In this presentation, we present the performances of both our first 384x288, 25 μm pitch, MWIR (3-5μm) / LWIR (8-9 μm) dual-band FPAs, and the current status of QWIPs for MWIR (< 5μm) and VLWIR (>15μm) arrays.
Lectin cDNA and transgenic plants derived therefrom
Raikhel, Natasha V.
2000-10-03
Transgenic plants containing cDNA encoding Gramineae lectin are described. The plants preferably contain cDNA coding for barley lectin and store the lectin in the leaves. The transgenic plants, particularly the leaves exhibit insecticidal and fungicidal properties.
Recent Progress on the Stretched Lens Array (SLA)
NASA Technical Reports Server (NTRS)
O'Neill, Markl; McDanal, A. J.; Piszczor, Michael; George, Patrick; Eskenazi, Michael; Botke, Matthew; Edwards, David; Hoppe, David; Brandhorst, Henry
2005-01-01
At the last Space Photovoltaic Research and Technology Conference, SPRAT XVII, held during the fateful week of 9/11/01, our team presented a paper on the early developments related to the new Stretched Lens Array (SLA), including its evolution from the successful SCARLET array on the NASA/JPL Deep Space 1 spacecraft. Within the past two years, the SLA team has made significant progress in the SLA technology, including the successful fabrication and testing of a complete four-panel prototype solar array wing (Fig. 1). The prototype wing verified the mechanical and structural design of the rigid-panel SLA approach, including multiple successful demonstrations of automatic wing deployment. One panel in the prototype wing included four fully functional photovoltaic receivers, employing triple-junction solar cells.
NASA Astrophysics Data System (ADS)
Zhao, Jian-Yi; Chen, Xin; Zhou, Ning; Huang, Xiao-Dong; Cao, Ming-De; Liu, Wen
2014-07-01
A 16-channel distributed-feedback (DFB) laser array with a monolithic integrated arrayed waveguide grating multiplexer for a wavelength division multiplex-passive optical network system is fabricated by using the butt-joint metal organic chemical vapor deposition technology and nanoimpirnt technology. The results show that the threshold current is about 20-30 mA at 25°C. The DFB laser side output power is about 16 mW with a 150 mA injection current. The lasing wavelength is from 1550 nm to 1575 nm covering a more than 25 nm range with 200 GHz channel space. A more than 55 dB sidemode suppression ratio is obtained.
Novel Permissive Cell Lines for Complete Propagation of Hepatitis C Virus
Shiokawa, Mai; Fukuhara, Takasuke; Ono, Chikako; Yamamoto, Satomi; Okamoto, Toru; Watanabe, Noriyuki; Wakita, Takaji
2014-01-01
ABSTRACT Hepatitis C virus (HCV) is a major etiologic agent of chronic liver diseases. Although the HCV life cycle has been clarified by studying laboratory strains of HCV derived from the genotype 2a JFH-1 strain (cell culture-adapted HCV [HCVcc]), the mechanisms of particle formation have not been elucidated. Recently, we showed that exogenous expression of a liver-specific microRNA, miR-122, in nonhepatic cell lines facilitates efficient replication but not particle production of HCVcc, suggesting that liver-specific host factors are required for infectious particle formation. In this study, we screened human cancer cell lines for expression of the liver-specific α-fetoprotein by using a cDNA array database and identified liver-derived JHH-4 cells and stomach-derived FU97 cells, which express liver-specific host factors comparable to Huh7 cells. These cell lines permit not only replication of HCV RNA but also particle formation upon infection with HCVcc, suggesting that hepatic differentiation participates in the expression of liver-specific host factors required for HCV propagation. HCV inhibitors targeting host and viral factors exhibited different antiviral efficacies between Huh7 and FU97 cells. Furthermore, FU97 cells exhibited higher susceptibility for propagation of HCVcc derived from the JFH-2 strain than Huh7 cells. These results suggest that hepatic differentiation participates in the expression of liver-specific host factors required for complete propagation of HCV. IMPORTANCE Previous studies have shown that liver-specific host factors are required for efficient replication of HCV RNA and formation of infectious particles. In this study, we screened human cancer cell lines for expression of the liver-specific α-fetoprotein by using a cDNA array database and identified novel permissive cell lines for complete propagation of HCVcc without any artificial manipulation. In particular, gastric cancer-derived FU97 cells exhibited a much higher susceptibility to HCVcc/JFH-2 infection than observed in Huh7 cells, suggesting that FU97 cells would be useful for further investigation of the HCV life cycle, as well as the development of therapeutic agents for chronic hepatitis C. PMID:24599999
Kebebew, Electron; Peng, Miao; Reiff, Emily; Duh, Quan-Yang; Clark, Orlo H.; McMillan, Alex
2005-01-01
Objective: The objective of this study was to determine whether genes that regulate cellular invasion and metastasis are differentially expressed and could serve as diagnostic markers of malignant thyroid nodules. Summary and Background Data: Patients whose thyroid nodules have indeterminate or suspicious cytologic features on fine needle aspiration (FNA) biopsy require thyroidectomy because of a 20% to 30% risk of thyroid cancer. Cell invasion and metastasis is a hallmark of malignant phenotype; therefore, genes that regulate these processes might be differentially expressed and could serve as diagnostic markers of malignancy. Methods: Differentially expressed genes (2-fold higher or lower) in malignant versus benign thyroid neoplasms were identified by extracellular matrix and adhesion molecule cDNA array analysis and confirmed by real-time quantitative polymerase chain reaction (PCR). The area under the receiver operating characteristic (AUC) curve was calculated to determine diagnostic accuracy of gene expression level cutoffs established by logistic regression analysis. Results: By cDNA array analysis, ADAMTS8, ECM1, MMP8, PLAU, SELP, and TMPRSS4 were upregulated, and by quantitative PCR, ECM1, SELP, and TMPRSS4 mRNA expression was higher in malignant (n = 57) than in benign (n = 38) thyroid neoplasms (P< 0.002). ECM1 and TMPRSS4 mRNA expression levels were independent predictors of a malignant thyroid neoplasm (P < 0.003). The AUC was 0.956 for ECM1 and 0.926 for TMPRSS4. Combining both markers improved their diagnostic use (AUC 0.985; sensitivity, 91.7%; specificity, 89.8%; positive predictive value, 85.7%; negative predictive value, 82.8%). ECM1 and TMPRSS4 expression analysis improved the diagnostic accuracy of FNA biopsy in 35 of 38 indeterminate or suspicious results. The level of ECM1 mRNA expression was higher in TNM stage I differentiated thyroid cancers than in stage II and III tumors (P ≤ 0.031). Conclusions: ECM1 and TMPRSS4 are excellent diagnostic markers of malignant thyroid nodules and may be used to improve the diagnostic accuracy of FNA biopsy. ECM1 is also a marker of the extent of disease in differentiated thyroid cancers. PMID:16135921
Future sensor system needs for staring arrays
NASA Astrophysics Data System (ADS)
Miller, John Lester
2011-05-01
This is a systems application paper regarding how sensor systems may use future technology FPAs. A historical perspective is discussed along with lessons learned from previous technologies. Future system requirements for strained super-lattice (SLS), quantum dots (QDOT) and traditional quantum well infrared photo-diodes (QWIP) arrays will be presented from both a commercial and military perspective. New potential markets will open up in the future if certain FPA technologies can reduce cost and provide higher sensitivities at higher operating temperatures.
The application of DNA microarrays in gene expression analysis.
van Hal, N L; Vorst, O; van Houwelingen, A M; Kok, E J; Peijnenburg, A; Aharoni, A; van Tunen, A J; Keijer, J
2000-03-31
DNA microarray technology is a new and powerful technology that will substantially increase the speed of molecular biological research. This paper gives a survey of DNA microarray technology and its use in gene expression studies. The technical aspects and their potential improvements are discussed. These comprise array manufacturing and design, array hybridisation, scanning, and data handling. Furthermore, it is discussed how DNA microarrays can be applied in the working fields of: safety, functionality and health of food and gene discovery and pathway engineering in plants.
Packaging and testing of multi-wavelength DFB laser array using REC technology
NASA Astrophysics Data System (ADS)
Ni, Yi; Kong, Xuan; Gu, Xiaofeng; Chen, Xiangfei; Zheng, Guanghui; Luan, Jia
2014-02-01
Packaging of distributed feedback (DFB) laser array based on reconstruction-equivalent-chirp (REC) technology is a bridge from chip to system, and influences the practical process of REC chip. In this paper, DFB laser arrays of 4-channel @1310 nm and 8-channel @1550 nm are packaged. Our experimental results show that both these laser arrays have uniform wavelength spacing and larger than 35 dB average Side Mode Suppression Ratio (SMSR). When I=35 mA, we obtain the total output power of 1 mW for 4-channel @1310 nm, and 227 μw for 8-channel @1550 nm respectively. The high frequency characteristics of the packaged chips are also obtained, and the requirements for 4×10 G or even 8×10 G systems can be reached. Our results demonstrate the practical and low cost performance of REC technology and indicate its potential in the future fiber-to-the-home (FTTH) application.
Application of Nexus copy number software for CNV detection and analysis.
Darvishi, Katayoon
2010-04-01
Among human structural genomic variation, copy number variants (CNVs) are the most frequently known component, comprised of gains/losses of DNA segments that are generally 1 kb in length or longer. Array-based comparative genomic hybridization (aCGH) has emerged as a powerful tool for detecting genomic copy number variants (CNVs). With the rapid increase in the density of array technology and with the adaptation of new high-throughput technology, a reliable and computationally scalable method for accurate mapping of recurring DNA copy number aberrations has become a main focus in research. Here we introduce Nexus Copy Number software, a platform-independent tool, to analyze the output files of all types of commercial and custom-made comparative genomic hybridization (CGH) and single-nucleotide polymorphism (SNP) arrays, such as those manufactured by Affymetrix, Agilent Technologies, Illumina, and Roche NimbleGen. It also supports data generated by various array image-analysis software tools such as GenePix, ImaGene, and BlueFuse. (c) 2010 by John Wiley & Sons, Inc.
Isolation of CYP3A5P cDNA from human liver: a reflection of a novel cytochrome P-450 pseudogene.
Schuetz, J D; Guzelian, P S
1995-03-14
We have isolated, from a human liver cDNA library, a 1627 bp CYP3A5 cDNA variant (CYP3A5P) that contains several large insertions, deletions, and in-frame termination codons. By comparison with the genomic structure of other CYP3A genes, the major insertions in CYP3A5P cDNA demarcate the inferred sites of several CYP3A5 exons. The segments inserted in CYP3A5P have no homology with splice donor acceptor sites. It is unlikely that CYP3A5P cDNA represents an artifact of the cloning procedures since Southern blot analysis of human genomic DNA disclosed that CYP3A5P cDNA hybridized with a DNA fragment distinct from fragments that hybridized with either CYP3A5, CYP3A3 or CYP3A4. Moreover, analysis of adult human liver RNA on Northern blots hybridized with a CYP3A5P cDNA fragment revealed the presence of an mRNA with the predicted size of CYP3A5P. We conclude that CYP3A5P cDNA was derived from a separate gene, CYP3A5P, most likely a pseudogene evolved from CYP3A5.
Monolithic Microwave Integrated Circuit (MMIC) Phased Array Demonstrated With ACTS
NASA Technical Reports Server (NTRS)
1996-01-01
Monolithic Microwave Integrated Circuit (MMIC) arrays developed by the NASA Lewis Research Center and the Air Force Rome Laboratory were demonstrated in aeronautical terminals and in mobile or fixed Earth terminals linked with NASA's Advanced Communications Technology Satellite (ACTS). Four K/Ka-band experimental arrays were demonstrated between May 1994 and May 1995. Each array had GaAs MMIC devices at each radiating element for electronic beam steering and distributed power amplification. The 30-GHz transmit array used in uplinks to ACTS was developed by Lewis and Texas Instruments. The three 20-GHz receive arrays used in downlinks from ACTS were developed in cooperation with the Air Force Rome Laboratory, taking advantage of existing Air Force integrated-circuit, active-phased-array development contracts with the Boeing Company and Lockheed Martin Corporation. Four demonstrations, each related to an application of high interest to both commercial and Department of Defense organizations, were conducted. The location, type of link, and the data rate achieved for each of the applications is shown. In one demonstration-- an aeronautical terminal experiment called AERO-X--a duplex voice link between an aeronautical terminal on the Lewis Learjet and ACTS was achieved. Two others demonstrated duplex voice links (and in one case, interactive video links as well) between ACTS and an Army high-mobility, multipurpose wheeled vehicle (HMMWV, or "humvee"). In the fourth demonstration, the array was on a fixed mount and was electronically steered toward ACTS. Lewis served as project manager for all demonstrations and as overall system integrator. Lewis engineers developed the array system including a controller for open-loop tracking of ACTS during flight and HMMWV motion, as well as a laptop data display and recording system used in all demonstrations. The Jet Propulsion Laboratory supported the AERO-X program, providing elements of the ACTS Mobile Terminal. The successful performance of experimental, proof-of-concept MMIC K/Ka-band arrays developed with U.S. industry in field demonstrations with ACTS indicates that high density MMIC integration at 20 and 30 GHz is indeed feasible. The successful development and demonstration of the MMIC array systems was possible only because of significant intergovernmental and Government/industry cooperation and the high level of teamwork within Lewis. The results provide a strong incentive for continuing the focused development of MMIC-array technology for satellite communications applications, with emphasis on packaging and cost issues, and for continuing the planning and conducting of other appropriate demonstrations or experiments of phased-array technology with ACTS. Given the present pressures on reducing funding for research and development in Government and industry, the extent to which this can be continued in a cooperative manner will determine whether MMIC array technology will make the transition from the proof-of-concept level to the operational system level.
Zhao, Wei; Li, Xin; Liu, Wen-Hui; Zhao, Jian; Jin, Yi-Ming; Sui, Ting-Ting
2014-09-01
Human epithelial colorectal adenocarcinoma (Caco-2) cells are widely used as an in vitro model of the human small intestinal mucosa. Caco-2 cells are host cells of the human astrovirus (HAstV) and other enteroviruses. High quality cDNA libraries are pertinent resources and critical tools for protein-protein interaction research, but are currently unavailable for Caco-2 cells. To construct a three-open reading frame, full length-expression cDNA library from the Caco-2 cell line for application to HAstV protein-protein interaction screening, total RNA was extracted from Caco-2 cells. The switching mechanism at the 5' end of the RNA transcript technique was used for cDNA synthesis. Double-stranded cDNA was digested by Sfi I and ligated to reconstruct a pGADT7-Sfi I three-frame vector. The ligation mixture was transformed into Escherichia coli HST08 premium electro cells by electroporation to construct the primary cDNA library. The library capacity was 1.0×10(6)clones. Gel electrophoresis results indicated that the fragments ranged from 0.5kb to 4.2kb. Randomly picked clones show that the recombination rate was 100%. The three-frame primary cDNA library plasmid mixture (5×10(5)cfu) was also transformed into E. coli HST08 premium electro cells, and all clones were harvested to amplify the cDNA library. To detect the sufficiency of the cDNA library, HAstV capsid protein as bait was screened and tested against the Caco-2 cDNA library by a yeast two-hybrid (Y2H) system. A total of 20 proteins were found to interact with the capsid protein. These results showed that a high-quality three-frame cDNA library from Caco-2 cells was successfully constructed. This library was efficient for the application to the Y2H system, and could be used for future research. Copyright © 2014 Elsevier B.V. All rights reserved.
Multistage WDM access architecture employing cascaded AWGs
NASA Astrophysics Data System (ADS)
El-Nahal, F. I.; Mears, R. J.
2009-03-01
Here we propose passive/active arrayed waveguide gratings (AWGs) with enhanced performance for system applications mainly in novel access architectures employing cascaded AWG technology. Two technologies were considered to achieve space wavelength switching in these networks. Firstly, a passive AWG with semiconductor optical amplifiers array, and secondly, an active AWG. Active AWG is an AWG with an array of phase modulators on its arrayed-waveguides section, where a programmable linear phase-profile or a phase hologram is applied across the arrayed-waveguide section. This results in a wavelength shift at the output section of the AWG. These architectures can address up to 6912 customers employing only 24 wavelengths, coarsely separated by 1.6 nm. Simulation results obtained here demonstrate that cascaded AWGs access architectures have a great potential in future local area networks. Furthermore, they indicate for the first time that active AWGs architectures are more efficient in routing signals to the destination optical network units than passive AWG architectures.
Stretched Lens Array Photovoltaic Concentrator Technology Developed
NASA Technical Reports Server (NTRS)
Piszczor, Michael F., Jr.; O'Neill, Mark J.
2004-01-01
Solar arrays have been and continue to be the mainstay in providing power to nearly all commercial and government spacecraft. Light from the Sun is directly converted into electrical energy using solar cells. One way to reduce the cost of future space power systems is by minimizing the size and number of expensive solar cells by focusing the sunlight onto smaller cells using concentrator optics. The stretched lens array (SLA) is a unique concept that uses arched Fresnel lens concentrators to focus sunlight onto a line of high-efficiency solar cells located directly beneath. The SLA concept is based on the Solar Concentrator Array with Refractive Linear Element Technology (SCARLET) design that was used on NASA's New Millennium Deep Space 1 mission. The highly successful asteroid/comet rendezvous mission (1998 to 2001) demonstrated the performance and long-term durability of the SCARLET/SLA solar array design and set the foundation for further improvements to optimize its performance.
Mission applications for advanced photovoltaic solar arrays
NASA Technical Reports Server (NTRS)
Stella, Paul M.; West, John L.; Chave, Robert G.; Mcgee, David P.; Yen, Albert S.
1990-01-01
The suitability of the Advanced Photovoltaic Solar Array (APSA) for future space missions was examined by considering the impact on the spacecraft system in general. The lightweight flexible blanket array system was compared to rigid arrays and a radio-isotope thermoelectric generator (RTG) static power source for a wide range of assumed future earth orbiting and interplanetary mission applications. The study approach was to establish assessment criteria and a rating scheme, identify a reference mission set, perform the power system assessment for each mission, and develop conclusions and recommendations to guide future APSA technology development. The authors discuss the three selected power sources, the assessment criteria and rating definitions, and the reference missions. They present the assessment results in a convenient tabular format. It is concluded that the three power sources examined, APSA, conventional solar arrays, and RTGs, can be considered to complement each other. Each power technology has its own range of preferred applications.
Thin-Film Solar Cells on Metal Foil Substrates for Space Power
NASA Technical Reports Server (NTRS)
Raffaelle, Ryne P.; Hepp, Aloysius F.; Hoffman, David J.; Dhere, N.; Tuttle, J. R.; Jin, Michael H.
2004-01-01
Photovoltaic arrays have played a key role in power generation in space. The current technology will continue to evolve but is limited in the important mass specific power metric (MSP or power/weight ratio) because it is based on bulk crystal technology. The objective of this research is to continue development of an innovative photovoltaic technology for satellite power sources that could provide up to an order of magnitude saving in both weight and cost, and is inherently radiation-tolerant through use of thin film technology and thin foil substrates such as 5-mil thick stainless steel foil or 1-mil thick Ti. Current single crystal technology for space power can cost more than $300 per watt at the array level and weigh more than 1 kg/sq m equivalent to specific power of approx. 65 W/kg. Thin film material such as CuIn(1-x),Ga(x)S2, (CIGS2), CuIn(1-x), G(x)Se(2-y),S(y), (CIGSS) or amorphous hydrogenated silicon (a-Si:H) may be able to reduce both the cost and mass per unit area by an order of magnitude. Manufacturing costs for solar arrays are an important consideration for total spacecraft budget. For a medium sized 5kW satellite, for example, the array manufacturing cost alone may exceed $2 million. Moving to thin film technology could reduce this expense to less than $500 K. Previous work at FSEC demonstrated the potential of achieving higher efficiencies from CIGSS thin film solar cells on 5-mil thick stainless steel foil as well as initial stages of facility augmentation for depositing thin film solar cells on larger (6"x 4") substrates. This paper presents further progress in processing on metal foil substrates. Also, previous work at DayStar demonstrated the feasibility of flexible-thin-film copper-indium-gallium-diselenide (CIGS) solar cells with a power-to-weight ratio in excess of 1000 W/kg. We will comment on progress on the critical issue of scale-up of the solar cell absorber deposition process. Several important technical issues need to be resolved to realize the benefits of lightweight technologies for solar arrays, such as: monolithic interconnects, lightweight array structures, and new ultra-light support and deployment mechanisms. Once the technology has gained spaceflight certification it should find rapid acceptance in specific satellite markets.
Implementation and Performance of GaAs Digital Signal Processing ASICs
NASA Technical Reports Server (NTRS)
Whitaker, William D.; Buchanan, Jeffrey R.; Burke, Gary R.; Chow, Terrance W.; Graham, J. Scott; Kowalski, James E.; Lam, Barbara; Siavoshi, Fardad; Thompson, Matthew S.; Johnson, Robert A.
1993-01-01
The feasibility of performing high speed digital signal processing in GaAs gate array technology has been demonstrated with the successful implementation of a VLSI communications chip set for NASA's Deep Space Network. This paper describes the techniques developed to solve some of the technology and implementation problems associated with large scale integration of GaAs gate arrays.
Spacecraft level impacts of integrating concentrator solar arrays
DOE Office of Scientific and Technical Information (OSTI.GOV)
Allen, D.M.; Piszczor, M.F. Jr.
1994-12-31
The paper describes the results of a study to determine the impacts of integrating concentrator solar arrays on spacecraft design and performance. First, concentrator array performance is summarized for the AEC-Able/Entech SCARLET array, the Ioffe refractive and reflective concepts being developed in Russia, the Martin Marietta SLATS system, and other concentrator concepts that have been designed or developed. Concentrator array performance is compared to rigid and flex blanket planar array technologies at the array level. Then other impacts on the spacecraft are quantified. Conclusions highlight the most important results as they relate to recommended approaches in developing concentrator arrays formore » satellites.« less
Integrated infrared detector arrays for low-background applications
NASA Technical Reports Server (NTRS)
Mccreight, C. R.; Goebel, J. H.
1982-01-01
Advanced infrared detector and detector array technology is being developed and characterized for future NASA space astronomy applications. Si:Bi charge-injection-device arrays have been obtained, and low-background sensitivities comparable to that of good discrete detectors have been measured. Intrinsic arrays are being assessed, and laboratory and telescope data have been collected on a monolithic InSb CCD array. For wavelengths longer than 30 microns, improved Ge:Ga detectors have been produced, and steps have been taken to prove the feasibility of an integrated extrinsic germanium array. Other integrated arrays and cryogenic components are also under investigation.
Sensor Modelling for the ’Cyclops’ Focal Plane Detector Array Based Technology Demonstrator
1992-12-01
Detector Array IFOV Instantaneous field of view IRFPDA Infrared Focal Plane Detector Array LWIR Long-Wave Infrared 0 MCT Mercury Cadmium Telluride MTF...scale focal plane detector array (FPDA). The sensor system operates in the long-wave infrared ( LWIR ) spectral region. The detector array consists of...charge transfer inefficiencies in the readout circuitry. The performance of the HgCdTe FPDA based sensor is limited by the nonuniformity of the
Operational considerations of the Advanced Photovoltaic Solar Array
NASA Technical Reports Server (NTRS)
Stella, Paul M.; Kurland, Richard M.
1992-01-01
Issues affecting the long-term operational performance of the Advanced Photovoltaic Solar Array (APSA) are discussed, with particular attention given to circuit electrical integrity from shadowed and cracked cell modules. The successful integration of individual advanced array components provides a doubling of array specific performance from the previous NASA-developed advanced array (SAFE). Flight test modules both recently fabricated and under fabrication are described. The development of advanced high-performance blanket technology for future APSA enhancement is presented.
Operational considerations of the Advanced Photovoltaic Solar Array
NASA Astrophysics Data System (ADS)
Stella, Paul M.; Kurland, Richard M.
Issues affecting the long-term operational performance of the Advanced Photovoltaic Solar Array (APSA) are discussed, with particular attention given to circuit electrical integrity from shadowed and cracked cell modules. The successful integration of individual advanced array components provides a doubling of array specific performance from the previous NASA-developed advanced array (SAFE). Flight test modules both recently fabricated and under fabrication are described. The development of advanced high-performance blanket technology for future APSA enhancement is presented.
Cloning and Expression of cDNA for Rat Heme Oxygenase
NASA Astrophysics Data System (ADS)
Shibahara, Shigeki; Muller, Rita; Taguchi, Hayao; Yoshida, Tadashi
1985-12-01
Two cDNA clones for rat heme oxygenase have been isolated from a rat spleen cDNA library in λ gt11 by immunological screening using a specific polyclonal antibody. One of these clones has an insert of 1530 nucleotides that contains the entire protein-coding region. To confirm that the isolated cDNA encodes heme oxygenase, we transfected monkey kidney cells (COS-7) with the cDNA carried in a simian virus 40 vector. The heme oxygenase was highly expressed in endoplasmic reticulum of transfected cells. The nucleotide sequence of the cloned cDNA was determined and the primary structure of heme oxygenase was deduced. Heme oxygenase is composed of 289 amino acids and has one hydrophobic segment at its carboxyl terminus, which is probably important for the insertion of heme oxygenase into endoplasmic reticulum. The cloned cDNA was used to analyze the induction of heme oxygenase in rat liver by treatment with CoCl2 or with hemin. RNA blot analysis showed that both CoCl2 and hemin increased the amount of hybridizable mRNA, suggesting that these substances may act at the transcriptional level to increase the amount of heme oxygenase.
Indarte, Martín; Lazza, Cristian M; Assis, Diego; Caffini, Néstor O; Juliano, María A; Avilés, Francesc X; Daura, Xavier; López, Laura M I; Trejo, Sebastián A
2017-02-01
A new BBI-type protease inhibitor with remarkable structural characteristics was purified, cloned, and sequenced from seeds of Maclura pomifera , a dicotyledonous plant belonging to the Moraceae family. In this work, we report a Bowman-Birk inhibitor (BBI) isolated, purified, cloned, and characterized from Maclura pomifera seeds (MpBBI), the first of this type from a species belonging to Moraceae family. MpBBI was purified to homogeneity by RP-HPLC, total RNA was extracted from seeds of M. pomifera, and the 3'RACE-PCR method was applied to obtain the cDNA, which was cloned and sequenced. Peptide mass fingerprinting (PMF) analysis showed correspondence between the in silico-translated protein and MpBBI, confirming that it corresponds to a new plant protease inhibitor. The obtained cDNA encoded a polypeptide of 65 residues and possesses 10 cysteine residues, with molecular mass of 7379.27, pI 6.10, and extinction molar coefficient of 9105 M -1 cm -1 . MpBBI inhibits strongly trypsin with K i in the 10 -10 M range and was stable in a wide array of pH and extreme temperatures. MpBBI comparative modeling was applied to gain insight into its 3D structure and highlighted some distinguishing features: (1) two non-identical loops, (2) loop 1 (CEEESRC) is completely different from any known BBI, and (3) the amount of disulphide bonds is also different from any reported BBI from dicot plants.
Dye bias correction in dual-labeled cDNA microarray gene expression measurements.
Rosenzweig, Barry A; Pine, P Scott; Domon, Olen E; Morris, Suzanne M; Chen, James J; Sistare, Frank D
2004-01-01
A significant limitation to the analytical accuracy and precision of dual-labeled spotted cDNA microarrays is the signal error due to dye bias. Transcript-dependent dye bias may be due to gene-specific differences of incorporation of two distinctly different chemical dyes and the resultant differential hybridization efficiencies of these two chemically different targets for the same probe. Several approaches were used to assess and minimize the effects of dye bias on fluorescent hybridization signals and maximize the experimental design efficiency of a cell culture experiment. Dye bias was measured at the individual transcript level within each batch of simultaneously processed arrays by replicate dual-labeled split-control sample hybridizations and accounted for a significant component of fluorescent signal differences. This transcript-dependent dye bias alone could introduce unacceptably high numbers of both false-positive and false-negative signals. We found that within a given set of concurrently processed hybridizations, the bias is remarkably consistent and therefore measurable and correctable. The additional microarrays and reagents required for paired technical replicate dye-swap corrections commonly performed to control for dye bias could be costly to end users. Incorporating split-control microarrays within a set of concurrently processed hybridizations to specifically measure dye bias can eliminate the need for technical dye swap replicates and reduce microarray and reagent costs while maintaining experimental accuracy and technical precision. These data support a practical and more efficient experimental design to measure and mathematically correct for dye bias. PMID:15033598
Gil-Serna, Jessica; Vázquez, Covadonga; González-Jaén, María Teresa; Patiño, Belén
2015-12-02
Aspergillus steynii is probably the most relevant species of section Circumdati producing ochratoxin A (OTA). This mycotoxin contaminates a wide number of commodities and it is highly toxic for humans and animals. Little is known on the biosynthetic genes and their regulation in Aspergillus species. In this work, we identified and analysed three contiguous genes in A. steynii using 5'-RACE and genome walking approaches which predicted a cytochrome P450 monooxygenase (p450ste), a non-ribosomal peptide synthetase (nrpsste) and a polyketide synthase (pksste). These three genes were contiguous within a 20742 bp long genomic DNA fragment. Their corresponding cDNA were sequenced and their expression was analysed in three A. steynii strains using real time RT-PCR specific assays in permissive conditions in in vitro cultures. OTA was also analysed in these cultures. Comparative analyses of predicted genomic, cDNA and amino acid sequences were performed with sequences of similar gene functions. All the results obtained in these analyses were consistent and point out the involvement of these three genes in OTA biosynthesis by A. steynii and showed a co-ordinated expression pattern. This is the first time that a clustered organization OTA biosynthetic genes has been reported in Aspergillus genus. The results also suggested that this situation might be common in Aspergillus OTA-producing species and distinct to the one described for Penicillium species. Copyright © 2015 Elsevier B.V. All rights reserved.
MILSTAR's flexible substrate solar array: Lessons learned, addendum
NASA Technical Reports Server (NTRS)
Gibb, John
1990-01-01
MILSTAR's Flexible Substrate Solar Array (FSSA) is an evolutionary development of the lightweight, flexible substrate design pioneered at Lockheed during the seventies. Many of the features of the design are related to the Solar Array Flight Experiment (SAFE), flown on STS-41D in 1984. FSSA development has created a substantial technology base for future flexible substrate solar arrays such as the array for the Space Station Freedom. Lessons learned during the development of the FSSA can and should be applied to the Freedom array and other future flexible substrate designs.
Soares, Marcelo B.; Efstratiadis, Argiris
1997-01-01
This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form comprising: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3' noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to moderate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library.
Soares, M.B.; Efstratiadis, A.
1997-06-10
This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form comprising: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3{prime} noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to moderate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library. 4 figs.
Study of multi-megawatt technology needs for photovoltaic space power systems, volume 2
NASA Technical Reports Server (NTRS)
Peterson, D. M.; Pleasant, R. L.
1981-01-01
Possible missions requiring multimegawatt photovoltaic space power systems in the 1990's time frame and power system technology needs associated with these missions are examined. Four specific task areas were considered: (1) missions requiring power in the 1-10 megawatt average power region; (2) alternative power systems and component technologies; (3) technology goals and sensitivity trades and analyses; and (4) technology recommendations. Specific concepts for photovoltaic power approaches considered were: planar arrays, concentrating arrays, hybrid systems using Rankine engines, thermophotovoltaic approaches; all with various photovoltaic cell component technologies. Various AC/DC power management approaches, and battery, fuel cell, and flywheel energy storage concepts are evaluated. Interactions with the electrical ion engine injection and stationkeeping system are also considered.
Molecular cloning of cDNAs for the nerve-cell specific phosphoprotein, synapsin I.
Kilimann, M W; DeGennaro, L J
1985-01-01
To provide access to synapsin I-specific DNA sequences, we have constructed cDNA clones complementary to synapsin I mRNA isolated from rat brain. Synapsin I mRNA was specifically enriched by immunoadsorption of polysomes prepared from the brains of 10-14 day old rats. Employing this enriched mRNA, a cDNA library was constructed in pBR322 and screened by differential colony hybridization with single-stranded cDNA probes made from synapsin I mRNA and total polysomal poly(A)+ RNA. This screening procedure proved to be highly selective. Five independent recombinant plasmids which exhibited distinctly stronger hybridization with the synapsin I probe were characterized further by restriction mapping. All of the cDNA inserts gave restriction enzyme digestion patterns which could be aligned. In addition, some of the cDNA inserts were shown to contain poly(dA) sequences. Final identification of synapsin I cDNA clones relied on the ability of the cDNA inserts to hybridize specifically to synapsin I mRNA. Several plasmids were tested by positive hybridization selection. They specifically selected synapsin I mRNA which was identified by in vitro translation and immunoprecipitation of the translation products. The established cDNA clones were used for a blot-hybridization analysis of synapsin I mRNA. A fragment (1600 bases) from the longest cDNA clone hybridized with two discrete RNA species 5800 and 4500 bases long, in polyadenylated RNA from rat brain and PC12 cells. No hybridization was detected to RNA from rat liver, skeletal muscle or cardiac muscle. Images Fig. 1. Fig. 2. Fig. 4. Fig. 5. PMID:3933975
Constructing and detecting a cDNA library for mites.
Hu, Li; Zhao, YaE; Cheng, Juan; Yang, YuanJun; Li, Chen; Lu, ZhaoHui
2015-10-01
RNA extraction and construction of complementary DNA (cDNA) library for mites have been quite challenging due to difficulties in acquiring tiny living mites and breaking their hard chitin. The present study is to explore a better method to construct cDNA library for mites that will lay the foundation on transcriptome and molecular pathogenesis research. We selected Psoroptes cuniculi as an experimental subject and took the following steps to construct and verify cDNA library. First, we combined liquid nitrogen grinding with TRIzol for total RNA extraction. Then, switching mechanism at 5' end of the RNA transcript (SMART) technique was used to construct full-length cDNA library. To evaluate the quality of cDNA library, the library titer and recombination rate were calculated. The reliability of cDNA library was detected by sequencing and analyzing positive clones and genes amplified by specific primers. The results showed that the RNA concentration was 836 ng/μl and the absorbance ratio at 260/280 nm was 1.82. The library titer was 5.31 × 10(5) plaque-forming unit (PFU)/ml and the recombination rate was 98.21%, indicating that the library was of good quality. In the 33 expressed sequence tags (ESTs) of P. cuniculi, two clones of 1656 and 1658 bp were almost identical with only three variable sites detected, which had an identity of 99.63% with that of Psoroptes ovis, indicating that the cDNA library was reliable. Further detection by specific primers demonstrated that the 553-bp Pso c II gene sequences of P. cuniculi had an identity of 98.56% with those of P. ovis, confirming that the cDNA library was not only reliable but also feasible.
Aptamer-based electrochemical sensors with aptamer-complementary DNA oligonucleotides as probe.
Lu, Ying; Li, Xianchan; Zhang, Limin; Yu, Ping; Su, Lei; Mao, Lanqun
2008-03-15
This study describes a facile and general strategy for the development of aptamer-based electrochemical sensors with a high specificity toward the targets and a ready regeneration feature. Very different from the existing strategies for the development of electrochemical aptasensors with the aptamers as the probes, the strategy proposed here is essentially based on the utilization of the aptamer-complementary DNA (cDNA) oligonucleotides as the probes for electrochemical sensing. In this context, the sequences at both ends of the cDNA are tailor-made to be complementary and both the redox moiety (i.e., ferrocene in this study) and thiol group are labeled onto the cDNA. The labeled cDNA are hybridized with their respective aptamers (i.e., ATP- and thrombin-binding aptamers in this study) to form double-stranded DNA (ds-DNA) and the electrochemical aptasensors are prepared by self-assembling the labeled ds-DNA onto Au electrodes. Upon target binding, the aptamers confined onto electrode surface dissociate from their respective cDNA oligonucleotides into the solution and the single-stranded cDNA could thus tend to form a hairpin structure through the hybridization of the complementary sequences at both its ends. Such a conformational change of the cDNA resulting from the target binding-induced dissociation of the aptamers essentially leads to the change in the voltammetric signal of the redox moiety labeled onto the cDNA and thus constitutes the mechanism for the electrochemical aptasensors for specific target sensing. The aptasensors demonstrated here with the cDNA as the probe are readily regenerated and show good responses toward the targets. This study may offer a new and relatively general approach to electrochemical aptasensors with good analytical properties and potential applications.
3G vector-primer plasmid for constructing full-length-enriched cDNA libraries.
Zheng, Dong; Zhou, Yanna; Zhang, Zidong; Li, Zaiyu; Liu, Xuedong
2008-09-01
We designed a 3G vector-primer plasmid for the generation of full-length-enriched complementary DNA (cDNA) libraries. By employing the terminal transferase activity of reverse transcriptase and the modified strand replacement method, this plasmid (assembled with a polydT end and a deoxyguanosine [dG] end) combines priming full-length cDNA strand synthesis and directional cDNA cloning. As a result, the number of steps involved in cDNA library preparation is decreased while simplifying downstream gene manipulation, sequencing, and subcloning. The 3G vector-primer plasmid method yields fully represented plasmid primed libraries that are equivalent to those made by the SMART (switching mechanism at 5' end of RNA transcript) approach.
GaAs QWIP Array Containing More Than a Million Pixels
NASA Technical Reports Server (NTRS)
Jhabvala, Murzy; Choi, K. K.; Gunapala, Sarath
2005-01-01
A 1,024 x 1,024-pixel array of quantum-well infrared photodetectors (QWIPs) has been built on a 1.8 x 1.8- cm GaAs chip. In tests, the array was found to perform well in detecting images at wavelengths from 8 to 9 m in operation at temperatures between 60 and 70 K. The largest-format QWIP prior array that performed successfully in tests contained 512 x 640 pixels. There is continuing development effort directed toward satisfying actual and anticipated demands to increase numbers of pixels and pixel sizes in order to increase the imaging resolution of infrared photodetector arrays. A 1,024 x 1,024-pixel and even larger formats have been achieved in the InSb and HgCdTe material systems, but photodetector arrays in these material systems are very expensive and manufactured by fewer than half a dozen large companies. In contrast, GaAs-photodetector-array technology is very mature, and photodetectors in the GaAs material system can be readily manufactured by a wide range of industrial technologists, by universities, and government laboratories. There is much similarity between processing in the GaAs industry and processing in the pervasive silicon industry. With respect to yield and cost, the performance of GaAs technology substantially exceeds that of InSb and HgCdTe technologies. In addition, GaAs detectors can be designed to respond to any portion of the wavelength range from 3 to about 16 micrometers - a feature that is very desirable for infrared imaging. GaAs QWIP arrays, like the present one, have potential for use as imaging sensors in infrared measuring instruments, infrared medical imaging systems, and infrared cameras.
NASA Technical Reports Server (NTRS)
Miller, Timothy M.; Costen, Nick; Allen, Christine
2007-01-01
The advance of new detector technologies combined with enhanced fabrication methods has resulted in an increase in development of large format arrays. The next generation of scientific instruments will utilize detectors containing hundreds to thousands of elements providing a more efficient means to conduct large area sky surveys. Some notable detectors include a 32x32 x-ray microcalorimeter for Constellation-X, an infrared bolometer called SAFIRE to fly on the airborne observatory SOFIA, and the sub-millimeter bolometer SCUBA-2 to be deployed at the JCMT which will use more than 10,000 elements for two colors, each color using four 32x40 arrays. Of these detectors, SCUBA-2 is farthest along in development and uses indium hybridization to multiplexers for readout of the large number of elements, a technology that will be required to enable the next generation of large format arrays. Our current efforts in working toward large format arrays have produced GISMO, the Goddard IRAM Superconducting 2-Millimeter observer. GISMO is a far infrared instrument to be field tested later this year at the IRAM 30 meter telescope in Spain. GISMO utilizes transition edge sensor (TES) technology in an 8x16 filled array format that allows for typical fan-out wiring and wire-bonding to four 1x32 NIST multiplexers. GISMO'S electrical wiring is routed along the tops of 30 micron walls which also serve as the mechanical framework for the array. This architecture works well for the 128 element array, but is approaching the limit for routing the necessary wires along the surface while maintaining a high fill factor. Larger format arrays will benefit greatly from making electrical connections through the wafer to the backside, where they can be hybridized to a read-out substrate tailored to handling the wiring scheme. The next generation array we are developing is a 32x40 element array on a pitch of 1135 microns that conforms to the NIST multiplexer, already developed for the SCUBA-2 instrument This architecture will utilize electrical connections that route from the TES to the support frame and through the wafer. The detector chip will then be hybridized to the NIST multiplexer via indium bump bonding. In our development scheme we are using substrates that allow for diagnostic testing of electrical continuity across the entire array and we are testing our process to minimize or eliminate any contact resistance at metal interfaces. Our goal is hybridizing a fully functional 32x40 array of TES bolometers to a NIST multiplexer. The following work presents our current progress toward enabling this technology.
Lee, Ra Mi; Ryu, Rae Hyung; Jeong, Seong Won; Oh, Soo Jin; Huang, Hue; Han, Jin Soo; Lee, Chi Ho; Lee, C. Justin; Jan, Lily Yeh
2011-01-01
To clone the first anion channel from Xenopus laevis (X. laevis), we isolated a calcium-activated chloride channel (CLCA)-like membrane protein 6 gene (CMP6) in X. laevis. As a first step in gene isolation, an expressed sequence tags database was screened to find the partial cDNA fragment. A putative partial cDNA sequence was obtained by comparison with rat CLCAs identified in our laboratory. First stranded cDNA was synthesized by reverse transcription polymerase-chain reaction (RT-PCR) using a specific primer designed for the target cDNA. Repeating the 5' and 3' rapid amplification of cDNA ends, full-length cDNA was constructed from the cDNA pool. The full-length CMP6 cDNA completed via 5'- and 3'-RACE was 2,940 bp long and had an open reading frame (ORF) of 940 amino acids. The predicted 940 polypeptides have four major transmembrane domains and showed about 50% identity with that of rat brain CLCAs in our previously published data. Semi-quantification analysis revealed that CMP6 was most abundantly expressed in small intestine, colon and liver. However, all tissues except small intestine, colon and liver had undetectable levels. This result became more credible after we did real-time PCR quantification for the target gene. In view of all CLCA studies focused on human or murine channels, this finding suggests a hypothetical protein as an ion channel, an X. laevis CLCA. PMID:21826170
NASA Technical Reports Server (NTRS)
Jones, B.
1985-01-01
This program was directed towards a better understanding of some of the important factors in the performance of infrared detector arrays at low background conditions appropriate for space astronomy. The arrays were manufactured by Aerojet Electrosystems Corporation, Azusa. Two arrays, both bismuth doped silicon, were investigated: an AMCID 32x32 Engineering mosiac Si:Bi accumulation mode charge injection device detector array and a metal oxide semiconductor/field effect transistor (MOS-FET) switched array of 16x32 pixels.
NASA Astrophysics Data System (ADS)
Bushel, Pierre R.; Bennett, Lee; Hamadeh, Hisham; Green, James; Ableson, Alan; Misener, Steve; Paules, Richard; Afshari, Cynthia
2002-06-01
We present an analysis of pattern recognition procedures used to predict the classes of samples exposed to pharmacologic agents by comparing gene expression patterns from samples treated with two classes of compounds. Rat liver mRNA samples following exposure for 24 hours with phenobarbital or peroxisome proliferators were analyzed using a 1700 rat cDNA microarray platform. Sets of genes that were consistently differentially expressed in the rat liver samples following treatment were stored in the MicroArray Project System (MAPS) database. MAPS identified 238 genes in common that possessed a low probability (P < 0.01) of being randomly detected as differentially expressed at the 95% confidence level. Hierarchical cluster analysis on the 238 genes clustered specific gene expression profiles that separated samples based on exposure to a particular class of compound.
Generation of Recombinant Ebola Viruses Using Reverse Genetics.
Groseth, Allison
2017-01-01
Reverse genetics systems encompass a wide array of tools aimed at recapitulating some or all of the virus life cycle. In their most complete form, full-length clone systems allow us to use plasmid-encoded versions of the ribonucleoprotein (RNP) components to initiate the transcription and replication of a plasmid-encoded version of the complete viral genome, thereby initiating the complete virus life cycle and resulting in infectious virus. As such this approach is ideal for the generation of tailor-made recombinant filoviruses, which can be used to study virus biology. In addition, the generation of tagged and particularly fluorescent or luminescent viruses can be applied as tools for both diagnostic applications and for screening to identify novel countermeasures. Here we describe the generation and basic characterization of recombinant Ebola viruses rescued from cloned cDNA using a T7-driven system.
Development of Microfabricated Chemical Gas Sensors and Sensor Arrays for Aerospace Applications
NASA Technical Reports Server (NTRS)
Hunter, G. W.; Neudeck, P. G.; Fralick, G.; Thomas, V.; Liu, C. C.; Wu, W. H.; Ward, B.; Makel, D.
2002-01-01
Aerospace applications require the development of chemical sensors with capabilities beyond those of commercially available sensors. In particular, factors such as minimal sensor size, weight, and power consumption are particularly important. Development areas which have potential aerospace applications include launch vehicle leak detection, engine health monitoring, fire detection, and environmental monitoring. Sensor development for these applications is based on progress in three types of technology: 1) Micromachining and microfabrication (Microsystem) technology to fabricate miniaturized sensors. 2) The use of nanocrystalline materials to develop sensors with improved stability combined with higher sensitivity. 3) The development of high temperature semiconductors, especially silicon carbide. However, due to issues of selectivity and cross-sensitivity, individual sensors are limited in the amount of information that they can provide in environments that contain multiple chemical species. Thus, sensor arrays are being developed to address detection needs in such multi-species environments. This paper discusses the needs of space applications as well as the point-contact sensor technology and sensor arrays being developed to address these needs. Sensors to measure hydrogen, hydrocarbons, hydrazine, nitrogen oxides (NO,), carbon monoxide, oxygen, and carbon dioxide are being developed as well as arrays for leak, fire, and emissions detection. Demonstrations of the technology will also be discussed. It is concluded that microfabricated sensor technology has significant potential for use in a range of aerospace applications.
Glyco-Immune Diagnostic Signatures and Therapeutic Targets of Mesothelioma
2015-09-01
Mesothelioma; Glycan Array; Immunoprofiles; Robotic Arrayer 16. SECURITY CLASSIFICATION OF: U 17. LIMITATION OF ABSTRACT: UU 18. NUMBER OF PAGES 19 19a...PROJECT SUMMARY: General Comments: This project involved novel technology in which biochemically synthesized glycans were robotically printed on glass...include 386 glycans and the platform was known as the PGA-400. (Figure 1) A standard robotic technology for printing a large range of
2010-01-01
dynein to move from the cell periphery to the microtubule organizing center [22]. Therefore, the initial interactions between host and intracellular...used to study host-pathogen interactions , mainly by identifying genes from pathogens that may be involved in pathogenecity and by surveying the scope...toward understanding the host-Orientia tsutsugamushi interaction at the molecular level, we used human cDNA microarray technology to examine in detail
This invention describes small cDNA fragments of the coding region for wild type filamin A interacting protein 1-like (FILIP1L) and variant 2 of FILIP1L genes that encode proteins inhibit cell migration and motility, induce cell apoptosis and inhibit cell proliferation. The significance of this invention is that it could provide for a series of new anti-cancer therapeutics and for the diagnostic means to follow their expression levels.
Improving RNA-Seq expression estimates by correcting for fragment bias
2011-01-01
The biochemistry of RNA-Seq library preparation results in cDNA fragments that are not uniformly distributed within the transcripts they represent. This non-uniformity must be accounted for when estimating expression levels, and we show how to perform the needed corrections using a likelihood based approach. We find improvements in expression estimates as measured by correlation with independently performed qRT-PCR and show that correction of bias leads to improved replicability of results across libraries and sequencing technologies. PMID:21410973
NASA Astrophysics Data System (ADS)
Samson, Philippe
2005-05-01
The constant evolution of the satellite market is asking for better technical performances and reliability for a reduced cost. Solar array is in front line of this challenge.This can be achieved by present technologies progressive improvement in cost reduction or by technological breakthrough.To reach an effective End Of Live performance100 W/kg of solar array is not so easy, even if you suppose that the mass of everything is nothing!Thin film cells are potential candidate to contribute to this challenge with certain confidence level and consequent development plan validation and qualification on ground and flight.Based on a strong flight heritage in flexible Solar Array design, the work has allowed in these last years, to pave the way on road map of thin film technologies . This is encouraged by ESA on many technological contracts put in concurrent engineering.CISG was selected cell and their strategy of design, contributions and results will be presented.Trade-off results and Design to Cost solutions will discussed.Main technical drivers, system design constraints, market access, key technologies needed will be detailed in this paper and the resulting road-map and development plan will be presented.
Microfabricated Chemical Gas Sensors and Sensor Arrays for Aerospace Applications
NASA Technical Reports Server (NTRS)
Hunter, Gary W.
2005-01-01
Aerospace applications require the development of chemical sensors with capabilities beyond those of commercially available sensors. In particular, factors such as minimal sensor size, weight, and power consumption are particularly important. Development areas which have potential aerospace applications include launch vehicle leak detection, engine health monitoring, and fire detection. Sensor development for these applications is based on progress in three types of technology: 1) Micromachining and microfabrication (Microsystem) technology to fabricate miniaturized sensors; 2) The use of nanocrystalline materials to develop sensors with improved stability combined with higher sensitivity; 3) The development of high temperature semiconductors, especially silicon carbide. This presentation discusses the needs of space applications as well as the point-contact sensor technology and sensor arrays being developed to address these needs. Sensors to measure hydrogen, hydrocarbons, nitrogen oxides (NO,), carbon monoxide, oxygen, and carbon dioxide are being developed as well as arrays for leak, fire, and emissions detection. Demonstrations of the technology will also be discussed. It is concluded that microfabricated sensor technology has significant potential for use in a range of aerospace applications.
Multispectral Linear Array detector technology
NASA Astrophysics Data System (ADS)
Tower, J. R.; McCarthy, B. M.; Pellon, L. E.; Strong, R. T.; Elabd, H.
1984-01-01
The Multispectral Linear Array (MLA) program sponsored by NASA has the aim to extend space-based remote sensor capabilities. The technology development effort involves the realization of very large, all-solid-state, pushbroom focal planes. The pushbroom, staring focal planes will contain thousands of detectors with the objective to provide two orders of magnitude improvement in detector dwell time compared to present Landsat mechanically scanned systems. Attenton is given to visible and near-infrared sensor development, the shortwave infrared sensor, aspects of filter technology development, the packaging concept, and questions of system performance. First-sample, four-band interference filters have been fabricated successfully, and a hybrid packaging technology is being developed.
Array-on-a-disk? How Blu-ray technology can be applied to molecular diagnostics.
Morais, Sergi; Tortajada-Genaro, Luis; Maquieira, Angel
2014-09-01
This editorial comments on the balance and perspectives of compact disk technology applied to molecular diagnostics. The development of sensitive, rapid and multiplex assays using Blu-ray technology for the determination of biomarkers, drug allergens, pathogens and detection of infections would have a direct impact on diagnostics. Effective tests for use in clinical, environmental and food applications require versatile and low-cost platforms as well as cost-effective detectors. Blu-ray technology accomplishes those requirements and advances on the concept of high density arrays for massive screening to achieve the demands of point of care or in situ analysis.
Microstrip technology and its application to phased array compensation
NASA Technical Reports Server (NTRS)
Dudgeon, J. E.; Daniels, W. D.
1972-01-01
A systematic analysis of mutual coupling compensation using microstrip techniques is presented. A method for behind-the-array coupling of a phased antenna array is investigated as to its feasibility. The matching scheme is tried on a rectangular array of one half lambda 2 dipoles, but it is not limited to this array element or geometry. In the example cited the values of discrete components necessary were so small an L-C network is needed for realization. Such L-C tanks might limit an otherwise broadband array match, however, this is not significant for this dipole array. Other areas investigated were balun feeding and power limits of spiral antenna elements.
Multi-kW solar arrays for Earth orbit applications
NASA Technical Reports Server (NTRS)
1985-01-01
The multi-kW solar array program is concerned with developing the technology required to enable the design of solar arrays required to power the missions of the 1990's. The present effort required the design of a modular solar array panel consisting of superstrate modules interconnected to provide the structural support for the solar cells. The effort was divided into two tasks: (1) superstrate solar array panel design, and (2) superstrate solar array panel-to-panel design. The primary objective was to systematically investigate critical areas of the transparent superstrate solar array and evaluate the flight capabilities of this low cost approach.
On-line monitoring system of PV array based on internet of things technology
NASA Astrophysics Data System (ADS)
Li, Y. F.; Lin, P. J.; Zhou, H. F.; Chen, Z. C.; Wu, L. J.; Cheng, S. Y.; Su, F. P.
2017-11-01
The Internet of Things (IoT) Technology is used to inspect photovoltaic (PV) array which can greatly improve the monitoring, performance and maintenance of the PV array. In order to efficiently realize the remote monitoring of PV operating environment, an on-line monitoring system of PV array based on IoT is designed in this paper. The system includes data acquisition, data gateway and PV monitoring centre (PVMC) website. Firstly, the DSP-TMS320F28335 is applied to collect indicators of PV array using sensors, then the data are transmitted to data gateway through ZigBee network. Secondly, the data gateway receives the data from data acquisition part, obtains geographic information via GPS module, and captures the scenes around PV array via USB camera, then uploads them to PVMC website. Finally, the PVMC website based on Laravel framework receives all data from data gateway and displays them with abundant charts. Moreover, a fault diagnosis approach for PV array based on Extreme Learning Machine (ELM) is applied in PVMC. Once fault occurs, a user alert can be sent via E-mail. The designed system enables users to browse the operating conditions of PV array on PVMC website, including electrical, environmental parameters and video. Experimental results show that the presented monitoring system can efficiently real-time monitor the PV array, and the fault diagnosis approach reaches a high accuracy of 97.5%.
Method for construction of normalized cDNA libraries
Soares, Marcelo B.; Efstratiadis, Argiris
1996-01-01
This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form comprising: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3' noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to moderate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library.
Method for construction of normalized cDNA libraries
Soares, M.B.; Efstratiadis, A.
1996-01-09
This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form. The method comprises: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3` noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to moderate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library. 4 figs.
Characterization of embryo-specific genes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1989-01-01
The objective of the proposed research is to characterize the structure and function of a set of genes whose expression is regulated in embryo development, and that is not expressed in mature tissues -- the embryonic genes. In the last two years, using cDNA clones, we have isolated 22 cDNA clones, and characterized the expression pattern of their corresponding RNA. At least 4 cDNA clones detect RNAs of embryonic genes. These cDNA clones detect RNAs expressed in somatic as well as zygotic embryos of carrot. Using the cDNA clones, we screened the genomic library of carrot embryo DNA, and isolatedmore » genomic clones for three genes. The structure and function of two genes DC 8 and DC 59 have been characterized and are reported in this paper.« less
Rise, Matthew L.; von Schalburg, Kristian R.; Brown, Gordon D.; Mawer, Melanie A.; Devlin, Robert H.; Kuipers, Nathanael; Busby, Maura; Beetz-Sargent, Marianne; Alberto, Roberto; Gibbs, A. Ross; Hunt, Peter; Shukin, Robert; Zeznik, Jeffrey A.; Nelson, Colleen; Jones, Simon R.M.; Smailus, Duane E.; Jones, Steven J.M.; Schein, Jacqueline E.; Marra, Marco A.; Butterfield, Yaron S.N.; Stott, Jeff M.; Ng, Siemon H.S.; Davidson, William S.; Koop, Ben F.
2004-01-01
We report 80,388 ESTs from 23 Atlantic salmon (Salmo salar) cDNA libraries (61,819 ESTs), 6 rainbow trout (Oncorhynchus mykiss) cDNA libraries (14,544 ESTs), 2 chinook salmon (Oncorhynchus tshawytscha) cDNA libraries (1317 ESTs), 2 sockeye salmon (Oncorhynchus nerka) cDNA libraries (1243 ESTs), and 2 lake whitefish (Coregonus clupeaformis) cDNA libraries (1465 ESTs). The majority of these are 3′ sequences, allowing discrimination between paralogs arising from a recent genome duplication in the salmonid lineage. Sequence assembly reveals 28,710 different S. salar, 8981 O. mykiss, 1085 O. tshawytscha, 520 O. nerka, and 1176 C. clupeaformis putative transcripts. We annotate the submitted portion of our EST database by molecular function. Higher- and lower-molecular-weight fractions of libraries are shown to contain distinct gene sets, and higher rates of gene discovery are associated with higher-molecular weight libraries. Pyloric caecum library group annotations indicate this organ may function in redox control and as a barrier against systemic uptake of xenobiotics. A microarray is described, containing 7356 salmonid elements representing 3557 different cDNAs. Analyses of cross-species hybridizations to this cDNA microarray indicate that this resource may be used for studies involving all salmonids. PMID:14962987
Detector arrays for low-background space infrared astronomy
NASA Technical Reports Server (NTRS)
Mccreight, C. R.; Mckelvey, M. E.; Goebel, J. H.; Anderson, G. M.; Lee, J. H.
1986-01-01
The status of development and characterization tests of integrated infrared detector array technology for astronomy applications is described. The devices under development include intrinsic, extrinsic silicon, and extrinsic germanium detectors, with hybrid silicon multiplexers. Laboratory test results and successful astronomy imagery have established the usefulness of integrated arrays in low-background astronomy applications.
Detector arrays for low-background space infrared astronomy
NASA Technical Reports Server (NTRS)
Mccreight, C. R.; Mckelvey, M. E.; Goebel, J. H.; Anderson, G. M.; Lee, J. H.
1986-01-01
The status of development and characterization tests of integrated infrared detector array technology for astronomy applications is described. The devices under development include intrinsic, extrinsic silicon, and extrinsic germanium detectors, with hybrid silicon multiplexers. Laboratary test results and successful astronomy imagery have established the usefulness of integrated arrays in low-background astronomy applications.
Phased array-fed antenna configuration study: Technology assessment
NASA Technical Reports Server (NTRS)
Croswell, W. F.; Ball, D. E.; Taylor, R. C.
1983-01-01
Spacecraft array fed reflector antenna systems were assessed for particular application to a multiple fixed spot beam/multiple scanning spot beam system. Reflector optics systems are reviewed in addition to an investigation of the feasibility of the use of monolithic microwave integrated circuit power amplifiers and phase shifters in each element of the array feed.
A passive optical fibre hydrophone array utilising fibre Bragg grating sensors
NASA Astrophysics Data System (ADS)
Karas, Andrew R.; Papageorgiou, Anthony W.; Cook, Peter R.; Arkwright, John W.
2018-02-01
Many current high performance hydrophones use piezo-electric technology to measure sound pressure in water. These hydrophones are sensitive enough to detect any sound above the lowest ambient ocean acoustic noise, however cost of manufacture, weight and storage volume of the array as well as deployment and maintenance costs can limit their largescale application. Piezo-electric systems also have issues with electro-magnetic interference and the signature of the electrical cabling required in a large array. A fibre optic hydrophone array has advantages over the piezo-electric technology in these areas. This paper presents the operating principle of a passive optical fibre hydrophone array utilising Fibre Bragg Gratings (FBGs). The multiple FBG sensors are interrogated using a single solid state spectrometer which further reduces the cost of the deployed system. A noise equivalent power (NEP) comparison of the developed FBG hydrophone versus an existing piezo-electric hydrophone is presented as well as a comparison to the lowest ambient ocean acoustic noise (sea state zero). This research provides an important first step towards a cost effective multi sensor hydrophone array using FBGs.
The Stretched Lens Array SquareRigger (SLASR) for Space Power
NASA Technical Reports Server (NTRS)
Piszczor, Michael F.; O'Neill, Mark J.; Eskenazi, Michael I.; Brandhorst, Henry W.
2006-01-01
For the past three years, our team has been developing, refining, and maturing a unique solar array technology known as Stretched Lens Array SquareRigger (SLASR). SLASR offers an unprecedented portfolio of state-of-the-art performance metrics, including areal power density, specific power, stowed power density, high-voltage capability, radiation hardness, modularity, scalability, mass-producibility, and cost-effectiveness. SLASR is particularly well suited to high-power space missions, including solar electric propulsion (SEP) space tugs, major exploration missions to the Moon and Mars, and power-intensive military spacecraft. SLASR is also very well suited to high-radiation missions, since the cell shielding mass penalty is 85% less for the SLASR concentrator array than for one-sun planar arrays. The paper describes SLASR technology and presents significant results of developments to date in a number of key areas, from advances in the key components to full-scale array hardware fabrication and evaluation. A summary of SLASR s unprecedented performance metrics, both near-term and longer term, will be presented. Plans for future SLASR developments and near-term space applications will also be outlined.
Elad, Tal; Lee, Jin Hyung; Belkin, Shimshon; Gu, Man Bock
2008-01-01
Summary The coming of age of whole‐cell biosensors, combined with the continuing advances in array technologies, has prepared the ground for the next step in the evolution of both disciplines – the whole‐cell array. In the present review, we highlight the state‐of‐the‐art in the different disciplines essential for a functional bacterial array. These include the genetic engineering of the biological components, their immobilization in different polymers, technologies for live cell deposition and patterning on different types of solid surfaces, and cellular viability maintenance. Also reviewed are the types of signals emitted by the reporter cell arrays, some of the transduction methodologies for reading these signals and the mathematical approaches proposed for their analysis. Finally, we review some of the potential applications for bacterial cell arrays, and list the future needs for their maturation: a richer arsenal of high‐performance reporter strains, better methodologies for their incorporation into hardware platforms, design of appropriate detection circuits, the continuing development of dedicated algorithms for multiplex signal analysis and – most importantly – enhanced long‐term maintenance of viability and activity on the fabricated biochips. PMID:21261831
Experimental results for a prototype 3-D acoustic imaging system using an ultra-sparse planar array
NASA Astrophysics Data System (ADS)
Impagliazzo, John M.; Chiang, Alice M.; Broadstone, Steven R.
2002-11-01
A handheld high resolution sonar has been under development to provide Navy Divers with a 3-D acoustic imaging system for mine reconnaissance. An ultra-sparse planar array, consisting of 121 1 mm x1 mm, 2 MHz elements, was fabricated to provide 3-D acoustic images. The array was 10 cm x10 cm. A full array at this frequency with elements at half-wavelength spacing would consist of 16384 elements. The first phase of testing of the planar array was completed in September 2001 with the characterization of the array in the NUWC Acoustic Test Facility (ATF). The center frequency was 2 MHz with a 667 kHz bandwidth. A system-level technology demonstration will be conducted in July 2002 with a real-time beamformer and near real-time 3-D imaging software. The demonstration phase consists of imaging simple targets at a range of 3 m in the ATF. Experimental results obtained will be reported on. [Work supported by the Defense Applied Research Project Agency, Advance Technology Office, Dr. Theo Kooij, Program Manager.
Eclipse SteerTech liquid lenslet beam steering technology
NASA Astrophysics Data System (ADS)
Westfall, Raymond T.; Rogers, Stanley; Shannon, Kenneth C., III
2007-09-01
Eclipse SteerTech TM transmissive fluid state electrowetting technology has successfully demonstrated the ability to control the shape and position of a fluid lenslet. In its final form, the technology will incorporate a dual fluid lenslet approach capable of operating in extremely high acceleration environments. The beam steering system works on the principle of electro-wetting. A substrate is covered with a closely spaced array of, independently addressable, transparent, electrically conductive pixels utilizing Eclipse's proprietary EclipseTEC TM technology. By activating and deactivating selected EclipseTEC TM pixels in the proper sequence, the shape and position of fluid lenslets or arrays of lenslets can be dynamically changed at will. The position and shape of individual fluid lenslets may be accurately controlled on any flat, simply curved, or complex curved, transparent or reflective surface. The smaller the pixels the better control of the position and shape of the fluid lenslets. Information on the successful testing of the Eclipse SteerTech TM lenslet and discussion of its use in a de-centered lenslet array will be presented.
NASA Astrophysics Data System (ADS)
Hughes, R. C.; Drebing, C. G.
1990-04-01
The technology that led to very large scale integrated circuits on silicon chips also provides a basis for new microsensors that are small, inexpensive, low power, rugged, and reliable. Two examples of microsensors Sandia is developing that take advantage of this technology are the microelectronic chemical sensor array and the radiation sensing field effect transistor (RADFET). Increasingly, the technology of chemical sensing needs new microsensor concepts. Applications in this area include environmental monitoring, criminal investigations, and state-of-health monitoring, both for equipment and living things. Chemical microsensors can satisfy sensing needs in the industrial, consumer, aerospace, and defense sectors. The microelectronic chemical-sensor array may address some of these applications. We have fabricated six separate chemical gas sensing areas on the microelectronic chemical sensor array. By using different catalytic metals on the gate areas of the diodes, we can selectively sense several gases.
Fabrication of corner cube array retro-reflective structure with DLP-based 3D printing technology
NASA Astrophysics Data System (ADS)
Riahi, Mohammadreza
2016-06-01
In this article, the fabrication of a corner cube array retro-reflective structure is presented by using DLP-based 3D printing technology. In this additive manufacturing technology a pattern of a cube corner array is designed in a computer and sliced with specific software. The image of each slice is then projected from the bottom side of a reservoir, containing UV cure resin, utilizing a DLP video projector. The projected area is cured and attached to a base plate. This process is repeated until the entire part is made. The best orientation of the printing process and the effect of layer thicknesses on the surface finish of the cube has been investigated. The thermal reflow surface finishing and replication with soft molding has also been presented in this article.
Biomimetic Cross-Reactive Sensor Arrays: Prospects in Biodiagnostics
Fitzgerald, J. E.
2016-01-01
Biomimetic cross-reactive sensor arrays have been used to detect and analyze a wide variety of vapour and liquid components in applications such as food science, public health and safety, and diagnostics. As technology has advanced over the past three decades, these systems have become selective, sensitive, and affordable. Currently, the need for non-invasive and accurate devices for early disease diagnosis remains a challenge. This review provides an overview of the various types of Biomimetic cross-reactive sensor arrays (also referred to as electronic noses and tongues in the literature), their current use and future directions, and an outlook for future technological development. PMID:28217300
Fabrication of cell container arrays with overlaid surface topographies.
Truckenmüller, Roman; Giselbrecht, Stefan; Escalante-Marun, Maryana; Groenendijk, Max; Papenburg, Bernke; Rivron, Nicolas; Unadkat, Hemant; Saile, Volker; Subramaniam, Vinod; van den Berg, Albert; van Blitterswijk, Clemens; Wessling, Matthias; de Boer, Jan; Stamatialis, Dimitrios
2012-02-01
This paper presents cell culture substrates in the form of microcontainer arrays with overlaid surface topographies, and a technology for their fabrication. The new fabrication technology is based on microscale thermoforming of thin polymer films whose surfaces are topographically prepatterned on a micro- or nanoscale. For microthermoforming, we apply a new process on the basis of temporary back moulding of polymer films and use the novel concept of a perforated-sheet-like mould. Thermal micro- or nanoimprinting is applied for prepatterning. The novel cell container arrays are fabricated from polylactic acid (PLA) films. The thin-walled microcontainer structures have the shape of a spherical calotte merging into a hexagonal shape at their upper circumferential edges. In the arrays, the cell containers are arranged densely packed in honeycomb fashion. The inner surfaces of the highly curved container walls are provided with various topographical micro- and nanopatterns. For a first validation of the microcontainer arrays as in vitro cell culture substrates, C2C12 mouse premyoblasts are cultured in containers with microgrooved surfaces and shown to align along the grooves in the three-dimensional film substrates. In future stem-cell-biological and tissue engineering applications, microcontainers fabricated using the proposed technology may act as geometrically defined artificial microenvironments or niches.
NeuroSeek dual-color image processing infrared focal plane array
NASA Astrophysics Data System (ADS)
McCarley, Paul L.; Massie, Mark A.; Baxter, Christopher R.; Huynh, Buu L.
1998-09-01
Several technologies have been developed in recent years to advance the state of the art of IR sensor systems including dual color affordable focal planes, on-focal plane array biologically inspired image and signal processing techniques and spectral sensing techniques. Pacific Advanced Technology (PAT) and the Air Force Research Lab Munitions Directorate have developed a system which incorporates the best of these capabilities into a single device. The 'NeuroSeek' device integrates these technologies into an IR focal plane array (FPA) which combines multicolor Midwave IR/Longwave IR radiometric response with on-focal plane 'smart' neuromorphic analog image processing. The readout and processing integrated circuit very large scale integration chip which was developed under this effort will be hybridized to a dual color detector array to produce the NeuroSeek FPA, which will have the capability to fuse multiple pixel-based sensor inputs directly on the focal plane. Great advantages are afforded by application of massively parallel processing algorithms to image data in the analog domain; the high speed and low power consumption of this device mimic operations performed in the human retina.
NASA Technical Reports Server (NTRS)
2002-01-01
Glenn Research Center sponsored an SBIR contract with ENTECH, in which the company worked to mold its successful terrestrial concentrator technology into applications that would generate solar power for space missions. ENTECH's first application made use of small, dome-shaped Fresnel lenses to direct sunlight onto high- efficiency photovoltaic cells. After some key adjustments, the mini- dome lens array was flown as part of the U.S. Air Force/NASA Photovoltaic Array Space Power Plus Diagnostics (PASP Plus) flight experiment in 1994. Due to their three-dimensional shape, the mini- dome lenses entailed construction by a batch molding process, which is naturally more costly than a continuous process. To overcome this disadvantage and meet the requirement for precise solar pointing in two axes, ENTECH started developing solar concentrator arrays for space using a line-focus lens that can be mass-produced by a continuous process. This new technology, named Solar Concentrator Array with Refractive Linear Element Technology (SCARLET), was created with support from Glenn and the Ballistic Missile Defense Organization, and was used to power the NASA/Jet Propulsion Laboratory Deep Space 1 spacecraft.
Multilevel photonic modules for millimeter-wave phased-array antennas
NASA Astrophysics Data System (ADS)
Paolella, Arthur C.; Bauerle, Athena; Joshi, Abhay M.; Wright, James G.; Coryell, Louis A.
2000-09-01
Millimeter wave phased array systems have antenna element sizes and spacings similar to MMIC chip dimensions by virtue of the operating wavelength. Designing modules in traditional planar packaing techniques are therefore difficult to implement. An advantageous way to maintain a small module footprint compatible with Ka-Band and high frequency systems is to take advantage of two leading edge technologies, opto- electronic integrated circuits (OEICs) and multilevel packaging technology. Under a Phase II SBIR these technologies are combined to form photonic modules for optically controlled millimeter wave phased array antennas. The proposed module, consisting of an OEIC integrated with a planar antenna array will operate on the 40GHz region. The OEIC consists of an InP based dual-depletion PIN photodetector and distributed amplifier. The multi-level module will be fabricated using an enhanced circuit processing thick film process. Since the modules are batch fabricated using an enhanced circuit processing thick film process. Since the modules are batch fabricated, using standard commercial processes, it has the potential to be low cost while maintaining high performance, impacting both military and commercial communications systems.
Chernicky, C L; Tan, H; Burfeind, P; Ilan, J; Ilan, J
1996-02-01
There are several cell types within the placenta that produce cytokines which can contribute to the regulatory mechanisms that ensure normal pregnancy. The immunological milieu at the maternofetal interface is considered to be crucial for survival of the fetus. Interleukin-2 (IL-2) is expressed by the syncytiotrophoblast, the cell layer between the mother and the fetus. IL-2 appears to be a key factor in maintenance of pregnancy. Therefore, it was important to determine the sequence of human placental interleukin-2. Direct sequencing of human placental IL-2 cDNA was determined for the coding region. Subclone sequencing was carried out for the 5'- and 3'-untranslated regions (5'-UTR and 3'-UTR). The 5'-UTR for human placental IL-2 cDNA is 294 bp, which is 247 nucleotides longer than that reported for cDNA IL-2 derived from T cells. The sequence of the coding region is identical to that reported for T cell IL-2, while sequence analysis of the polymerase chain reaction (PCR) product showed that the cDNA from the 3' end was the same as that reported for cDNA from T cells. Human placental IL-2 cDNA is 1,028 base pairs (excluding the poly A tail), which is 247 bp longer at the 5' end than that reported for IL-2 T cell cDNA. Therefore, the extended 5'-UTR of the placental IL-2 cDNA may be a consequence of alternative promoter utilization in the placenta.
Phase 1 of the automated array assembly task of the low cost silicon solar array project
NASA Technical Reports Server (NTRS)
Coleman, M. G.; Pryor, R. A.; Grenon, L. A.; Lesk, I. A.
1977-01-01
The state of technology readiness for the automated production of solar cells and modules is reviewed. Individual process steps and process sequences for making solar cells and modules were evaluated both technically and economically. High efficiency with a suggested cell goal of 15% was stressed. It is concluded that the technology exists to manufacture solar cells which will meet program goals.
Gowrisankar, Sivakumar; Lerner-Ellis, Jordan P; Cox, Stephanie; White, Emily T; Manion, Megan; LeVan, Kevin; Liu, Jonathan; Farwell, Lisa M; Iartchouk, Oleg; Rehm, Heidi L; Funke, Birgit H
2010-11-01
Medical sequencing for diseases with locus and allelic heterogeneities has been limited by the high cost and low throughput of traditional sequencing technologies. "Second-generation" sequencing (SGS) technologies allow the parallel processing of a large number of genes and, therefore, offer great promise for medical sequencing; however, their use in clinical laboratories is still in its infancy. Our laboratory offers clinical resequencing for dilated cardiomyopathy (DCM) using an array-based platform that interrogates 19 of more than 30 genes known to cause DCM. We explored both the feasibility and cost effectiveness of using PCR amplification followed by SGS technology for sequencing these 19 genes in a set of five samples enriched for known sequence alterations (109 unique substitutions and 27 insertions and deletions). While the analytical sensitivity for substitutions was comparable to that of the DCM array (98%), SGS technology performed better than the DCM array for insertions and deletions (90.6% versus 58%). Overall, SGS performed substantially better than did the current array-based testing platform; however, the operational cost and projected turnaround time do not meet our current standards. Therefore, efficient capture methods and/or sample pooling strategies that shorten the turnaround time and decrease reagent and labor costs are needed before implementing this platform into routine clinical applications.
Design and Development of the Space Technology 5 (ST5) Solar Arrays
NASA Technical Reports Server (NTRS)
Lyons, John; Fatemi, Navid; Gamica, Robert; Sharma, Surya; Senft, Donna; Maybery, Clay
2005-01-01
The National Aeronautics and Space Administration's (NASA's) Space Technology 5 (ST5) is designed to flight-test the concept of miniaturized 'small size" satellites and innovative technologies in Earth's magnetosphere. Three satellites will map the intensity and direction of the magnetic fields within the inner magnetosphere. Due to the small area available for the solar arrays, and to meet the mission power requirements, very high-efficiency multijunction solar cells were selected to power the spacecraft built by NASA Goddard Space Flight Center (GSFC). This was done in partnership with the Air Force Research Lab (AFRL) through the Dual-Use Science and Technology (DUS&T) program. Emcore's InGaP/lnGaAs/Ge Advanced triple-junction (ATJ) solar cells, exhibiting an average air mass zero (AMO) efficiency of 28.0% (one-sun, 28 C), were used to populate the arrays. Each spacecraft employs 8 identical solar panels (total area of about 0.3 square meters), with 15 large-area solar cells per panel. The requirement for power is to support on-orbit average load of 13.5 W at 8.4 V, with plus or minus 5% off pointing. The details of the solar array design, development and qualification considerations, as well as ground electrical performance & shadowing analysis results are presented.
Limits in point to point resolution of MOS based pixels detector arrays
NASA Astrophysics Data System (ADS)
Fourches, N.; Desforge, D.; Kebbiri, M.; Kumar, V.; Serruys, Y.; Gutierrez, G.; Leprêtre, F.; Jomard, F.
2018-01-01
In high energy physics point-to-point resolution is a key prerequisite for particle detector pixel arrays. Current and future experiments require the development of inner-detectors able to resolve the tracks of particles down to the micron range. Present-day technologies, although not fully implemented in actual detectors, can reach a 5-μm limit, this limit being based on statistical measurements, with a pixel-pitch in the 10 μm range. This paper is devoted to the evaluation of the building blocks for use in pixel arrays enabling accurate tracking of charged particles. Basing us on simulations we will make here a quantitative evaluation of the physical and technological limits in pixel size. Attempts to design small pixels based on SOI technology will be briefly recalled here. A design based on CMOS compatible technologies that allow a reduction of the pixel size below the micrometer is introduced here. Its physical principle relies on a buried carrier-localizing collecting gate. The fabrication process needed by this pixel design can be based on existing process steps used in silicon microelectronics. The pixel characteristics will be discussed as well as the design of pixel arrays. The existing bottlenecks and how to overcome them will be discussed in the light of recent ion implantation and material characterization experiments.
Passive Bottom Loss Estimation Using Compact Arrays and Autonomous Underwater Vehicles
2015-09-30
advances in the technology of autonomous underwater vehicles ( AUV ), make it now possible to envision an efficient, cost effective survey tool for seabed...characterization composed of a short array mounted on an AUV . While AUV mounting would require arrays of length presumably below 2m, the passive...frequency range indicated above, the poor angular resolution of the short arrays required in AUV deployment causes an underestimation of the loss
Infectious Maize rayado fino virus from cloned cDNA
USDA-ARS?s Scientific Manuscript database
Maize rayado fino virus (MRFV) is the type member of the marafiviruses within the family Tymoviridae. A cDNA clone from which infectious RNA can be transcribed was produced from a US isolate of MRFV (MRFV-US). Infectivity of transcripts derived from cDNA clones was demonstrated by infection of mai...
cDNA encoding a polypeptide including a hevein sequence
Raikhel, N.V.; Broekaert, W.F.; Namhai Chua; Kush, A.
1993-02-16
A cDNA clone (HEV1) encoding hevein was isolated via polymerase chain reaction (PCR) using mixed oligonucleotides corresponding to two regions of hevein as primers and a Hevea brasiliensis latex cDNA library as a template. HEV1 is 1,018 nucleotides long and includes an open reading frame of 204 amino acids.
Lu, L; Komada, M; Kitamura, N
1998-06-15
Hrs is a 115kDa zinc finger protein which is rapidly tyrosine phosphorylated in cells stimulated with various growth factors. We previously purified the protein from a mouse cell line and cloned its cDNA. In the present study, we cloned a human Hrs cDNA from a human placenta cDNA library by cross-hybridization, using the mouse cDNA as a probe, and determined its nucleotide sequence. The human Hrs cDNA encoded a 777-amino-acid protein whose sequence was 93% identical to that of mouse Hrs. Northern blot analysis showed that the Hrs mRNA was about 3.0kb long and was expressed in all the human adult and fetal tissues tested. In addition, we showed by genomic Southern blot analysis that the human Hrs gene was a single-copy gene with a size of about 20kb. Furthermore, the human Hrs gene was mapped to chromosome 17 by Southern blotting of genomic DNAs from human/rodent somatic cell hybrids. Copyright 1998 Elsevier Science B.V. All rights reserved.
The cDNA-derived amino acid sequence of hemoglobin II from Lucina pectinata.
Torres-Mercado, Elineth; Renta, Jessicca Y; Rodríguez, Yolanda; López-Garriga, Juan; Cadilla, Carmen L
2003-11-01
Hemoglobin II from the clam Lucina pectinata is an oxygen-reactive protein with a unique structural organization in the heme pocket involving residues Gln65 (E7), Tyr30 (B10), Phe44 (CD1), and Phe69 (E11). We employed the reverse transcriptase-polymerase chain reaction (RT-PCR) and methods to synthesize various cDNA(HbII). An initial 300-bp cDNA clone was amplified from total RNA by RT-PCR using degenerate oligonucleotides. Gene-specific primers derived from the HbII-partial cDNA sequence were used to obtain the 5' and 3' ends of the cDNA by RACE. The length of the HbII cDNA, estimated from overlapping clones, was approximately 2114 bases. Northern blot analysis revealed that the mRNA size of HbII agrees with the estimated size using cDNA data. The coding region of the full-length HbII cDNA codes for 151 amino acids. The calculated molecular weight of HbII, including the heme group and acetylated N-terminal residue, is 17,654.07 Da.
Generation of a reliable full-length cDNA of infectiousTembusu virus using a PCR-based protocol.
Liang, Te; Liu, Xiaoxiao; Cui, Shulin; Qu, Shenghua; Wang, Dan; Liu, Ning; Wang, Fumin; Ning, Kang; Zhang, Bing; Zhang, Dabing
2016-02-02
Full-length cDNA of Tembusu virus (TMUV) cloned in a plasmid has been found instable in bacterial hosts. Using a PCR-based protocol, we generated a stable full-length cDNA of TMUV. Different cDNA fragments of TMUV were amplified by reverse transcription (RT)-PCR, and cloned into plasmids. Fragmented cDNAs were amplified and assembled by fusion PCR to produce a full-length cDNA using the recombinant plasmids as templates. Subsequently, a full-length RNA was transcribed from the full-length cDNA in vitro and transfected into BHK-21 cells; infectious viral particles were rescued successfully. Following several passages in BKH-21 cells, the rescued virus was compared with the parental virus by genetic marker checks, growth curve determinations and animal experiments. These assays clearly demonstrated the genetic and biological stabilities of the rescued virus. The present work will be useful for future investigations on the molecular mechanisms involved in replication and pathogenesis of TMUV. Copyright © 2015 Elsevier B.V. All rights reserved.
Tange, N; Jong-Young, L; Mikawa, N; Hirono, I; Aoki, T
1997-12-01
A cDNA clone of rainbow trout (Oncorhynchus mykiss) transferrin was obtained from a liver cDNA library. The 2537-bp cDNA sequence contained an open reading frame encoding 691 amino acids and the 5' and 3' noncoding regions. The amino acid sequences at the iron-binding sites and the two N-linked glycosylation sites, and the cysteine residues were consistent with known, conserved vertebrate transferrin cDNA sequences. Single N-linked glycosylation sites existed on the N- and C-lobe. The deduced amino acid sequence of the rainbow trout transferrin cDNA had 92.9% identities with transferrin of coho salmon (Oncorhynchus kisutch); 85%, Atlantic salmon (Salmo salar); 67.3%, medaka (Oryzias latipes); 61.3% Atlantic cod (Gadus morhua); and 59.7%, Japanese flounder (Paralichthys olivaceus). The long and accurate polymerase chain reaction (LA-PCR) was used to amplify approximately 6.5 kb of the transferrin gene from rainbow trout genomic DNA. Restriction fragment length polymorphisms (RFLPs) of the LA-PCR products revealed three digestion patterns in 22 samples.
A cDNA microarray gene expression data classifier for clinical diagnostics based on graph theory.
Benso, Alfredo; Di Carlo, Stefano; Politano, Gianfranco
2011-01-01
Despite great advances in discovering cancer molecular profiles, the proper application of microarray technology to routine clinical diagnostics is still a challenge. Current practices in the classification of microarrays' data show two main limitations: the reliability of the training data sets used to build the classifiers, and the classifiers' performances, especially when the sample to be classified does not belong to any of the available classes. In this case, state-of-the-art algorithms usually produce a high rate of false positives that, in real diagnostic applications, are unacceptable. To address this problem, this paper presents a new cDNA microarray data classification algorithm based on graph theory and is able to overcome most of the limitations of known classification methodologies. The classifier works by analyzing gene expression data organized in an innovative data structure based on graphs, where vertices correspond to genes and edges to gene expression relationships. To demonstrate the novelty of the proposed approach, the authors present an experimental performance comparison between the proposed classifier and several state-of-the-art classification algorithms.
Liao, Yi-Hung; Chou, Jung-Chuan; Lin, Chin-Yi
2013-01-01
Fault diagnosis (FD) and data fusion (DF) technologies implemented in the LabVIEW program were used for a ruthenium dioxide pH sensor array. The purpose of the fault diagnosis and data fusion technologies is to increase the reliability of measured data. Data fusion is a very useful statistical method used for sensor arrays in many fields. Fault diagnosis is used to avoid sensor faults and to measure errors in the electrochemical measurement system, therefore, in this study, we use fault diagnosis to remove any faulty sensors in advance, and then proceed with data fusion in the sensor array. The average, self-adaptive and coefficient of variance data fusion methods are used in this study. The pH electrode is fabricated with ruthenium dioxide (RuO2) sensing membrane using a sputtering system to deposit it onto a silicon substrate, and eight RuO2 pH electrodes are fabricated to form a sensor array for this study. PMID:24351636
Liao, Yi-Hung; Chou, Jung-Chuan; Lin, Chin-Yi
2013-12-13
Fault diagnosis (FD) and data fusion (DF) technologies implemented in the LabVIEW program were used for a ruthenium dioxide pH sensor array. The purpose of the fault diagnosis and data fusion technologies is to increase the reliability of measured data. Data fusion is a very useful statistical method used for sensor arrays in many fields. Fault diagnosis is used to avoid sensor faults and to measure errors in the electrochemical measurement system, therefore, in this study, we use fault diagnosis to remove any faulty sensors in advance, and then proceed with data fusion in the sensor array. The average, self-adaptive and coefficient of variance data fusion methods are used in this study. The pH electrode is fabricated with ruthenium dioxide (RuO2) sensing membrane using a sputtering system to deposit it onto a silicon substrate, and eight RuO2 pH electrodes are fabricated to form a sensor array for this study.
Nonimaging applications for microbolometer arrays
NASA Astrophysics Data System (ADS)
Picard, Francis; Jerominek, Hubert; Pope, Timothy D.; Zhang, Rose; Ngo, Linh P.; Tremblay, Bruno; Tasker, Nick; Grenier, Carol; Bilodeau, Ghislain; Cayer, Felix; Lehoux, Mario; Alain, Christine; Larouche, Carl; Savard, Simon
2001-10-01
In an effort to leverage uncooled microbolometer technology, testing of bolometer performance in various nonimaging applications has been performed. One of these applications makes use of an uncooled microbolometer array as the sensing element for a laser beam analyzer. Results of the characterization of cw CO2 laser beams with this analyzer are given. A comparison with the results obtained with a commercial laser beam analyzer is made. Various advantages specific to microbolometer arrays for this application are identified. A second application makes use of microbolometers for absolute temperature measurements. The experimental method and results are described. The technique's limitations and possible implementations are discussed. Finally, the third application evaluated is related to the rapidly expanding field of biometry. It consists of using a modified microbolometer array for fingerprint sensing. The basic approach allowing the use of microbolometers for such an application is discussed. The results of a proof-of-principle experiment are described. Globally, the described work illustrates the fact that microbolometer array fabrication technology can be exploited for many important applications other than IR imaging.
Li, Xiaoyi; Liang, Renrong; Tao, Juan; Peng, Zhengchun; Xu, Qiming; Han, Xun; Wang, Xiandi; Wang, Chunfeng; Zhu, Jing; Pan, Caofeng; Wang, Zhong Lin
2017-04-25
Due to the fragility and the poor optoelectronic performances of Si, it is challenging and exciting to fabricate the Si-based flexible light-emitting diode (LED) array devices. Here, a flexible LED array device made of Si microwires-ZnO nanofilm, with the advantages of flexibility, stability, lightweight, and energy savings, is fabricated and can be used as a strain sensor to demonstrate the two-dimensional pressure distribution. Based on piezo-phototronic effect, the intensity of the flexible LED array can be increased more than 3 times (under 60 MPa compressive strains). Additionally, the device is stable and energy saving. The flexible device can still work well after 1000 bending cycles or 6 months placed in the atmosphere, and the power supplied to the flexible LED array is only 8% of the power of the surface-contact LED. The promising Si-based flexible device has wide range application and may revolutionize the technologies of flexible screens, touchpad technology, and smart skin.
Signal Processing for a Lunar Array: Minimizing Power Consumption
NASA Technical Reports Server (NTRS)
D'Addario, Larry; Simmons, Samuel
2011-01-01
Motivation for the study is: (1) Lunar Radio Array for low frequency, high redshift Dark Ages/Epoch of Reionization observations (z =6-50, f=30-200 MHz) (2) High precision cosmological measurements of 21 cm H I line fluctuations (3) Probe universe before first star formation and provide information about the Intergalactic Medium and evolution of large scale structures (5) Does the current cosmological model accurately describe the Universe before reionization? Lunar Radio Array is for (1) Radio interferometer based on the far side of the moon (1a) Necessary for precision measurements, (1b) Shielding from earth-based and solar RFI (12) No permanent ionosphere, (2) Minimum collecting area of approximately 1 square km and brightness sensitivity 10 mK (3)Several technologies must be developed before deployment The power needed to process signals from a large array of nonsteerable elements is not prohibitive, even for the Moon, and even in current technology. Two different concepts have been proposed: (1) Dark Ages Radio Interferometer (DALI) (2)( Lunar Array for Radio Cosmology (LARC)
Luo, Jingyi; Jiang, Danfeng; Liu, Tao; Peng, Jingmeng; Chu, Zhenyu; Jin, Wanqin
2018-05-01
In this work, a novel sandwich-type aptasensor was designed for the ultrasensitive recognition of trace mercury ions in water. Numerous oriented platinum nanotube arrays (PtNAs) were in-situ crystallized on a flexible electrode as a sensing interface, while thionine labelled Fe 3 O 4 /rGO nanocomposites as signal amplifiers. Both PtNAs/CF and nanocomposites were synthesized by easy hydrothermal processes. With their large surface area, it was favorable for electrochemical performance and immobilization of capture DNAs (cDNA) and report DNAs (rDNA). Upon the existence of Hg 2+ , partial linker DNAs were tightly bound with cDNAs through thymine-Hg 2+ -thymine pairing (T-Hg 2+ -T). Then rDNAs attached Fe 3 O 4 /rGO nanoprobes were fixed on the electrode through the match of remaining linker DNAs and rDNAs. Under the optimal conditions, the Hg 2+ aptasensor showed a synergistic amplification performance with a wide linear range from 0.1nM to 100nM, as well as a low detection limit of 30pM. Moreover, the as-prepared aptasensor also exhibited reliable performance for assay in real lake water samples. Copyright © 2017. Published by Elsevier B.V.
Kettunen, Eeva; Anttila, Sisko; Seppänen, Jouni K; Karjalainen, Antti; Edgren, Henrik; Lindström, Irmeli; Salovaara, Reijo; Nissén, Anna-Maria; Salo, Jarmo; Mattson, Karin; Hollmén, Jaakko; Knuutila, Sakari; Wikman, Harriet
2004-03-01
The expression patterns of cancer-related genes in 13 cases of squamous cell lung cancer (SCC) were characterized and compared with those in normal lung tissue and 13 adenocarcinomas (AC), the other major type of nonsmall cell lung cancer (NSCLC). cDNA array was used to screen the gene expression levels and the array results were verified using a real-time reverse-transcriptase-polymerase chain reaction (RT-PCR). Thirty-nine percent of the 25 most upregulated and the 25 most downregulated genes were common to SCC and AC. Of these genes, DSP, HMGA1 (alias HMGIY), TIMP1, MIF, CCNB1, TN, MMP11, and MMP12 were upregulated and COPEB (alias CPBP), TYROBP, BENE, BMPR2, SOCS3, TIMP3, CAV1, and CAV2 were downregulated. The expression levels of several genes from distinct protein families (cytokeratins and hemidesmosomal proteins) were markedly increased in SCC compared with AC and normal lung. In addition, several genes, overexpressed in SCC, such as HMGA1, CDK4, IGFBP3, MMP9, MMP11, MMP12, and MMP14, fell into distinct chromosomal loci, which we have detected as gained regions on the basis of comparative genomic hybridization data. Our study revealed new candidate genes involved in NSCLC.
Zhang, Lin; Jia, Baoguang; Zou, Feng; Tan, Xiaofeng; Liu, Min; Song, Zhibo; Zeng, Yanling; Jiang, Nan; Yuan, Deyi
2014-01-01
Many flowering plants exhibit an important intraspecific reproductive barrier phenomenon, that is, self-incompatibility (SI), in which S-RNase genes play a significant role. To clarify the specific function of S-RNase genes in Chinese pears, the full length cDNA of PbS 26 -RNase was isolated by rapid amplification of cDNA ends (RACE) technology from Chinese white pear (Pyrus bretschneideri) cultivar "Hongpisu." The cDNA sequence for PbS 26 -RNase was deposited in GenBank under accession number EU081888. At the amino acid level, the PbS 26 -RNase displayed the highest similarity (96.9%) with PcSa-RNase of P. communis, and only seven amino acid differences were present in the two S-RNases. Phylogenetic analysis of rosaceous S-RNases indicated that the PbS 26 -RNase clustered with maloideous S-RNases, forming a subfamily-specific not a species-specific group. The PbS 26 -RNase gene was specifically expressed in the style but not other tissues/organs. The expression level of the PbS 26 -RNase gene rapidly increased at bell balloon stage (BBS), and then it dropped after pollination. However, the abundance of the PbS 26 -RNase gene transcript in the style was greater after cross-pollination than after self-pollination. In addition, a method for rapidly detecting the PbS 26 -RNase gene was developed via allele-specific primers design. The present study could provide a scientific basis for fully clarifying the mechanism of pear SI at the molecular level.
Jia, Baoguang; Liu, Min; Song, Zhibo; Zeng, Yanling; Jiang, Nan; Yuan, Deyi
2014-01-01
Many flowering plants exhibit an important intraspecific reproductive barrier phenomenon, that is, self-incompatibility (SI), in which S-RNase genes play a significant role. To clarify the specific function of S-RNase genes in Chinese pears, the full length cDNA of PbS 26 -RNase was isolated by rapid amplification of cDNA ends (RACE) technology from Chinese white pear (Pyrus bretschneideri) cultivar “Hongpisu.” The cDNA sequence for PbS 26 -RNase was deposited in GenBank under accession number EU081888. At the amino acid level, the PbS 26 -RNase displayed the highest similarity (96.9%) with PcSa-RNase of P. communis, and only seven amino acid differences were present in the two S-RNases. Phylogenetic analysis of rosaceous S-RNases indicated that the PbS 26 -RNase clustered with maloideous S-RNases, forming a subfamily-specific not a species-specific group. The PbS 26 -RNase gene was specifically expressed in the style but not other tissues/organs. The expression level of the PbS 26 -RNase gene rapidly increased at bell balloon stage (BBS), and then it dropped after pollination. However, the abundance of the PbS 26 -RNase gene transcript in the style was greater after cross-pollination than after self-pollination. In addition, a method for rapidly detecting the PbS 26 -RNase gene was developed via allele-specific primers design. The present study could provide a scientific basis for fully clarifying the mechanism of pear SI at the molecular level. PMID:24737959
Li, Hong-Mei; Guo, Kang; Yu, Zhuang; Feng, Rui; Xu, Ping
2015-07-01
Traditional diagnostic technology with tumor biomarkers is inefficient, expensive and requires a large number of serum samples. The purpose of this study was to construct human lung cancer protein chips with new lung cancer biomarkers screened by the T7-phage display library, and improve the early diagnosis rate of lung cancer. A T7-phage cDNA display library was constructed of fresh samples from 30 lung cancer patients. With biopanning and high-throughput screening, we gained the immunogenic phage clones from the cDNA library. The insert of selected phage was blasted at GeneBank for alignment to find the exact or the most similar known genes. Protein chips were then constructed and used to assay their expression level in lung cancer serum from 217 cases of lung cancer groups:80 cases of benign lung disease and 220 healthy controls. After four rounds of Biopanning and two rounds of enzyme-linked immunosorbent assay, 12 phage monoclonal samples were selected from 2880 phage monoclonal samples. After blasting at GeneBank, six similar genes were used to construct diagnostic protein chips. The protein chips were then used to assay expression level in lung cancer serum. The expression level of six genes in lung cancer groups was significantly higher than those in the other two groups (P < 0.05). In this study, we successfully constructed diagnostic protein chips with biomarkers selected from the lung cancer T7-phage cDNA library, which can be used for the early screening of lung cancer patients.
Procedure for normalization of cDNA libraries
Bonaldo, Maria DeFatima; Soares, Marcelo Bento
1997-01-01
This invention provides a method to normalize a cDNA library constructed in a vector capable of being converted to single-stranded circles and capable of producing complementary nucleic acid molecules to the single-stranded circles comprising: (a) converting the cDNA library in single-stranded circles; (b) generating complementary nucleic acid molecules to the single-stranded circles; (c) hybridizing the single-stranded circles converted in step (a) with complementary nucleic acid molecules of step (b) to produce partial duplexes to an appropriate Cot; (e) separating the unhybridized single-stranded circles from the hybridized single-stranded circles, thereby generating a normalized cDNA library.
Intermite, Giuseppe; McCarthy, Aongus; Warburton, Ryan E; Ren, Ximing; Villa, Federica; Lussana, Rudi; Waddie, Andrew J; Taghizadeh, Mohammad R; Tosi, Alberto; Zappa, Franco; Buller, Gerald S
2015-12-28
Single-photon avalanche diode (SPAD) detector arrays generally suffer from having a low fill-factor, in which the photo-sensitive area of each pixel is small compared to the overall area of the pixel. This paper describes the integration of different configurations of high efficiency diffractive optical microlens arrays onto a 32 × 32 SPAD array, fabricated using a 0.35 µm CMOS technology process. The characterization of SPAD arrays with integrated microlens arrays is reported over the spectral range of 500-900 nm, and a range of f-numbers from f/2 to f/22. We report an average concentration factor of 15 measured for the entire SPAD array with integrated microlens array. The integrated SPAD and microlens array demonstrated a very high uniformity in overall efficiency.
Non-biased and efficient global amplification of a single-cell cDNA library
Huang, Huan; Goto, Mari; Tsunoda, Hiroyuki; Sun, Lizhou; Taniguchi, Kiyomi; Matsunaga, Hiroko; Kambara, Hideki
2014-01-01
Analysis of single-cell gene expression promises a more precise understanding of molecular mechanisms of a living system. Most techniques only allow studies of the expressions for limited numbers of gene species. When amplification of cDNA was carried out for analysing more genes, amplification biases were frequently reported. A non-biased and efficient global-amplification method, which uses a single-cell cDNA library immobilized on beads, was developed for analysing entire gene expressions for single cells. Every step in this analysis from reverse transcription to cDNA amplification was optimized. By removing degrading excess primers, the bias due to the digestion of cDNA was prevented. Since the residual reagents, which affect the efficiency of each subsequent reaction, could be removed by washing beads, the conditions for uniform and maximized amplification of cDNAs were achieved. The differences in the amplification rates for randomly selected eight genes were within 1.5-folds, which could be negligible for most of the applications of single-cell analysis. The global amplification gives a large amount of amplified cDNA (>100 μg) from a single cell (2-pg mRNA), and that amount is enough for downstream analysis. The proposed global-amplification method was used to analyse transcript ratios of multiple cDNA targets (from several copies to several thousand copies) quantitatively. PMID:24141095
Phaneuf, D; Labelle, Y; Bérubé, D; Arden, K; Cavenee, W; Gagné, R; Tanguay, R M
1991-01-01
Type 1 hereditary tyrosinemia (HT) is an autosomal recessive disease characterized by a deficiency of the enzyme fumarylacetoacetate hydrolase (FAH; E.C.3.7.1.2). We have isolated human FAH cDNA clones by screening a liver cDNA expression library using specific antibodies and plaque hybridization with a rat FAH cDNA probe. A 1,477-bp cDNA was sequenced and shown to code for FAH by an in vitro transcription-translation assay and sequence homology with tryptic fragments of purified FAH. Transient expression of this FAH cDNA in transfected CV-1 mammalian cells resulted in the synthesis of an immunoreactive protein comigrating with purified human liver FAH on SDS-PAGE and having enzymatic activity as shown by the hydrolysis of the natural substrate fumarylacetoacetate. This indicates that the single polypeptide chain encoded by the FAH gene contains all the genetic information required for functional activity, suggesting that the dimer found in vivo is a homodimer. The human FAH cDNA was used as a probe to determine the gene's chromosomal localization using somatic cell hybrids and in situ hybridization. The human FAH gene maps to the long arm of chromosome 15 in the region q23-q25. Images Figure 1 Figure 3 Figure 4 Figure 6 Figure 8 PMID:1998338
Technology Developments in Radiation-Hardened Electronics for Space Environments
NASA Technical Reports Server (NTRS)
Keys, Andrew S.; Howell, Joe T.
2008-01-01
The Radiation Hardened Electronics for Space Environments (RHESE) project consists of a series of tasks designed to develop and mature a broad spectrum of radiation hardened and low temperature electronics technologies. Three approaches are being taken to address radiation hardening: improved material hardness, design techniques to improve radiation tolerance, and software methods to improve radiation tolerance. Within these approaches various technology products are being addressed including Field Programmable Gate Arrays (FPGA), Field Programmable Analog Arrays (FPAA), MEMS, Serial Processors, Reconfigurable Processors, and Parallel Processors. In addition to radiation hardening, low temperature extremes are addressed with a focus on material and design approaches. System level applications for the RHESE technology products are discussed.
LIGHTWEIGHT INTEGRATED SOLAR ARRAY AND TRANSCEIVER
2016-09-23
JOHN CARR, RIGHT, CO-PRINCIPAL INVESTIGATOR FOR NASA'S LIGHTWEIGHT INTEGRATED SOLAR ARRAY AND TRANSCEIVER PROJECT, TALKS WITH GREG LAUE, DIRECTOR OF AEROSPACE PRODUCTS FOR NEXOLVE, MANUFACTURER OF THE THIN-FILM TECHNOLOGY AND A PARTNER IN THE PROJECT.
Proceedings of the Low-Cost Solar Array Wafering Workshop
NASA Technical Reports Server (NTRS)
Morrison, A. D.
1982-01-01
The technology and economics of silicon ingot wafering for low cost solar arrays were discussed. Fixed and free abrasive sawing wire, ID, and multiblade sawing, materials, mechanisms, characterization, and innovative concepts were considered.
Navy Collaborative Integrated Information Technology Initiative (NAVCIITI)
2004-09-01
We investigated a new type of antenna array consisting of sub- elements that are excited together to form the primary element. All of the sub...elements of the array are excited for the highest operating band. Only the primary elements are excited for the low frequency band. This fractal geometry has...fully active array. The fully active input impedance is the input impedance of an element in an array when all elements are excited . It is a function
Haraksingh, Rajini R.; Abyzov, Alexej; Gerstein, Mark; Urban, Alexander E.; Snyder, Michael
2011-01-01
Accurate and efficient genome-wide detection of copy number variants (CNVs) is essential for understanding human genomic variation, genome-wide CNV association type studies, cytogenetics research and diagnostics, and independent validation of CNVs identified from sequencing based technologies. Numerous, array-based platforms for CNV detection exist utilizing array Comparative Genome Hybridization (aCGH), Single Nucleotide Polymorphism (SNP) genotyping or both. We have quantitatively assessed the abilities of twelve leading genome-wide CNV detection platforms to accurately detect Gold Standard sets of CNVs in the genome of HapMap CEU sample NA12878, and found significant differences in performance. The technologies analyzed were the NimbleGen 4.2 M, 2.1 M and 3×720 K Whole Genome and CNV focused arrays, the Agilent 1×1 M CGH and High Resolution and 2×400 K CNV and SNP+CGH arrays, the Illumina Human Omni1Quad array and the Affymetrix SNP 6.0 array. The Gold Standards used were a 1000 Genomes Project sequencing-based set of 3997 validated CNVs and an ultra high-resolution aCGH-based set of 756 validated CNVs. We found that sensitivity, total number, size range and breakpoint resolution of CNV calls were highest for CNV focused arrays. Our results are important for cost effective CNV detection and validation for both basic and clinical applications. PMID:22140474
NASA Technical Reports Server (NTRS)
Leonard, Regis F. (Editor); Bhasin, Kul B. (Editor)
1991-01-01
Consideration is given to MMICs for airborne phased arrays, monolithic GaAs integrated circuit millimeter wave imaging sensors, accurate design of multiport low-noise MMICs up to 20 GHz, an ultralinear low-noise amplifier technology for space communications, variable-gain MMIC module for space applications, a high-efficiency dual-band power amplifier for radar applications, a high-density circuit approach for low-cost MMIC circuits, coplanar SIMMWIC circuits, recent advances in monolithic phased arrays, and system-level integrated circuit development for phased-array antenna applications. Consideration is also given to performance enhancement in future communications satellites with MMIC technology insertion, application of Ka-band MMIC technology for an Orbiter/ACTS communications experiment, a space-based millimeter wave debris tracking radar, low-noise high-yield octave-band feedback amplifiers to 20 GHz, quasi-optical MESFET VCOs, and a high-dynamic-range mixer using novel balun structure.
NASA Astrophysics Data System (ADS)
Zhou, Yuan-Qi; Zhan, Li-Hua
2016-05-01
Composite stiffened-structure consists of the skin and stringer has been widely used in aircraft fuselage and wings. The main purpose of the article is to detect the composite material reinforced structure accurately and explore the relationship between defect formation and structural elements or curing process. Based on ultrasonic phased array inspection technology, the regularity of defects in the manufacture of composite materials are obtained, the correlation model between actual defects and nondestructive testing are established. The article find that the forming quality of deltoid area in T-stiffened structure is obviously improved by pre-curing, the defects of hat-stiffened structure are affected by the mandrel. The results show that the ultrasonic phased array inspection technology can be an effectively way for the detection of composite stiffened-structures, which become an important means to control the defects of composite and improve the quality of the product.
The human chondrosarcoma HCS-2/8 cell line is responsive to BMP-7, but not to IL-1beta.
Saas, Joachim; Gebauer, Matthias; Jacobi, Carsten; Haag, Jochen; Takigawa, Masaharu; Aigner, Thomas
2005-05-01
Cultures of primary chondrocytes as in vitro model systems for studying the cellular behavior of chondrocytes are notoriously difficult to cultivate and propagate. One way to circumvent these problems appears to be the use of immortalized/immortal chondrocytic cell lines. In the present study, we were interested whether the chondrosarcoma derived HCS-2/8 cells are suitable for studying major cellular reaction pattern in response to key anabolic (BMP-7) and catabolic (IL-1beta) factors. Therefore, we used cDNA array and real-time PCR technology in order to evaluate gene expression triggered by stimulation with IL-1beta (0,1-100 ng/ml) and BMP-7 in confluent monolayer cultures. HCS-2/8 cells hardly responded to IL-1beta, but showed good responsiveness to BMP-7. We found 12 genes up- and 17 significantly down-regulated by BMP-7 (out of 340 investigated genes). Besides the expected activation of anabolic genes chondrocytic cells after BMP-stimulation try to neutralize activation of the BMP-signalling cascade by expressing intra- and extracellular BMP-antagonists. Chondrosarcoma derived cell lines are a potential substitute for primary articular chondrocytes promising consistent expression of a differentiated chondrocyte phenotype with sufficient proliferative capacity. However, as shown by this study one needs to carefully select the cell line depending on the effects which one intends to study. In this respect, HCS-2/8 cells are a validated tool for studying BMP-effects on chondrocytes, but not e.g. effects of interleukin-1.
Wiesenfahrt, Tobias; Duanmu, Jingjie; Snider, Frances; Moerman, Don; Au, Vinci; Li-Leger, Erica; Flibotte, Stephane; Parker, Dylan M; Marshall, Craig J; Nishimura, Erin Osborne; Mains, Paul E; McGhee, James D
2018-05-04
The ELT-2 GATA factor normally functions in differentiation of the C. elegans endoderm, downstream of endoderm specification. We have previously shown that, if ELT-2 is expressed sufficiently early, it is also able to specify the endoderm and to replace all other members of the core GATA-factor transcriptional cascade (END-1, END-3, ELT-7). However, such rescue requires multiple copies (and presumably overexpression) of the end-1p :: elt-2 cDNA transgene; a single copy of the transgene does not rescue. We have made this observation the basis of a genetic screen to search for genetic modifiers that allow a single copy of the end-1p :: elt-2 cDNA transgene to rescue the lethality of the end-1 end-3 double mutant. We performed this screen on a strain that has a single copy insertion of the transgene in an end-1 end-3 background. These animals are kept alive by virtue of an extrachromosomal array containing multiple copies of the rescuing transgene; the extrachromosomal array also contains a toxin under heat shock control to counterselect for mutagenized survivors that have been able to lose the rescuing array. A screen of ∼14,000 mutagenized haploid genomes produced 17 independent surviving strains. Whole genome sequencing was performed to identify genes that incurred independent mutations in more than one surviving strain. The C. elegans gene tasp-1 was mutated in four independent strains. tasp-1 encodes the C. elegans homolog of Taspase, a threonine-aspartic acid protease that has been found, in both mammals and insects, to cleave several proteins involved in transcription, in particular MLL1/trithorax and TFIIA. A second gene, pqn-82 , was mutated in two independent strains and encodes a glutamine-asparagine rich protein. tasp-1 and pqn-82 were verified as loss-of-function modifiers of the end-1p :: elt-2 transgene by RNAi and by CRISPR/Cas9-induced mutations. In both cases, gene loss leads to modest increases in the level of ELT-2 protein in the early endoderm although ELT-2 levels do not strictly correlate with rescue. We suggest that tasp-1 and pqn-82 represent a class of genes acting in the early embryo to modulate levels of critical transcription factors or to modulate the responsiveness of critical target genes. The screen's design, rescuing lethality with an extrachromosomal transgene followed by counterselection, has a background survival rate of <10 -4 without mutagenesis and should be readily adapted to the general problem of identifying suppressors of C. elegans lethal mutations. Copyright © 2018 Wiesenfahrt et al.
NASA Astrophysics Data System (ADS)
Various papers on photovoltaics are presented. The general topics considered include: amorphous materials and cells; amorphous silicon-based solar cells and modules; amorphous silicon-based materials and processes; amorphous materials characterization; amorphous silicon; high-efficiency single crystal solar cells; multijunction and heterojunction cells; high-efficiency III-V cells; modeling and characterization of high-efficiency cells; LIPS flight experience; space mission requirements and technology; advanced space solar cell technology; space environmental effects and modeling; space solar cell and array technology; terrestrial systems and array technology; terrestrial utility and stand-alone applications and testing; terrestrial concentrator and storage technology; terrestrial stand-alone systems applications; terrestrial systems test and evaluation; terrestrial flatplate and concentrator technology; use of polycrystalline materials; polycrystalline II-VI compound solar cells; analysis of and fabrication procedures for compound solar cells.
Required technologies for a lunar optical UV-IR synthesis array
NASA Technical Reports Server (NTRS)
Johnson, Stewart W.; Wetzel, John P.
1992-01-01
A Lunar Optical UV-IR Synthesis Array (LOUISA) proposed to take advantage of the characteristics of the lunar environment requires appropriate advances in technology. These technologies are in the areas of contamination/interference control, test and evaluation, manufacturing, construction, autonomous operations and maintenance, power and heating/cooling, stable precision structures, optics, parabolic antennas, and communications/control. LOUISA needs to be engineered to operate for long periods with minimal intervention by humans or robots. What is essential for LOUISA operation is enforcement of a systems engineering approach that makes compatible all lunar operations associated with habitation, resource development, and science.
Optics Design for the U.S. SKA Technology Development Project Design Verification Antenna
NASA Technical Reports Server (NTRS)
Imbriale, W. A.; Baker, L.; Cortes-Medellin, G.
2012-01-01
The U.S. design concept for the Square Kilometer Array (SKA) program is based on utilizing a large number of 15 meter dish antennas. The Technology Development Project (TDP) is planning to design and build the first of these antennas to provide a demonstration of the technology and a solid base on which to estimate costs. This paper describes the performance of the selected optics design. It is a dual-shaped offset Gregorian design with a feed indexer that can accommodate corrugated horns, wide band single pixel feeds or phased array feeds.
Huang, Shengbing; Song, Wei; Lin, Qishui
2005-08-01
A membrane-bound protein was purified from rat liver mitochondria. After being digested with V8 protease, two peptides containing identical 14 amino acid residue sequences were obtained. Using the 14 amino acid peptide derived DNA sequence as gene specific primer, the cDNA of correspondent gene 5'-terminal and 3'-terminal were obtained by RACE technique. The full-length cDNA that encoded a protein of 616 amino acids was thus cloned, which included the above mentioned peptide sequence. The full length cDNA was highly homologous to that of human ETF-QO, indicating that it may be the cDNA of rat ETF-QO. ETF-QO is an iron sulfur protein located in mitochondria inner membrane containing two kinds of redox center: FAD and [4Fe-4S] center. After comparing the sequence from the cDNA of the 616 amino acids protein with that of the mature protein of rat liver mitochondria, it was found that the N terminal 32 amino acid residues did not exist in the mature protein, indicating that the cDNA was that of ETF-QOp. When the cDNA was expressed in Saccharomyces cerevisiae with inducible vectors, the protein product was enriched in mitochondrial fraction and exhibited electron transfer activity (NBT reductase activity) of ETF-QO. Results demonstrated that the 32 amino acid peptide was a mitochondrial targeting peptide, and both FAD and iron-sulfur cluster were inserted properly into the expressed ETF-QO. ETF-QO had a high level expression in rat heart, liver and kidney. The fusion protein of GFP-ETF-QO co-localized with mitochondria in COS-7 cells.
NASA Technical Reports Server (NTRS)
ONeill, Mark; Piszczor, Michael F.; Eskenazi, Michael I.; McDanal, A. J.; George, Patrick J.; Botke, Matthew M.; Brandhorst, Henry W.; Edwards, David L.; Jaster, Paul A.; Lyons, Valerie J. (Technical Monitor)
2002-01-01
At IECEC 2001, our team presented a paper on the new stretched lens array (SLA), including its evolution from the successful SCARLET array on the NASA/JPL Deep Space 1 spacecraft. Since that conference, the SLA team has made significant advances in the SLA technology, including component-level improvements, array-level optimization, space environment exposure testing, and prototype hardware fabrication and evaluation. This paper describes the evolved version of the SLA, highlighting recent improvements in the lens, solar cell, photovoltaic receiver, rigid panel structure, and complete solar array wing.
Boyd, Matthew T
2017-06-01
Three grid-connected monocrystalline silicon photovoltaic arrays have been instrumented with research-grade sensors on the Gaithersburg, MD campus of the National Institute of Standards and Technology (NIST). These arrays range from 73 kW to 271 kW and have different tilts, orientations, and configurations. Irradiance, temperature, wind, and electrical measurements at the arrays are recorded, and images are taken of the arrays to monitor shading and capture any anomalies. A weather station has also been constructed that includes research-grade instrumentation to measure all standard meteorological quantities plus additional solar irradiance spectral bands, full spectrum curves, and directional components using multiple irradiance sensor technologies. Reference photovoltaic (PV) modules are also monitored to provide comprehensive baseline measurements for the PV arrays. Images of the whole sky are captured, along with images of the instrumentation and reference modules to document any obstructions or anomalies. Nearly, all measurements at the arrays and weather station are sampled and saved every 1s, with monitoring having started on Aug. 1, 2014. This report describes the instrumentation approach used to monitor the performance of these photovoltaic systems, measure the meteorological quantities, and acquire the images for use in PV performance and weather monitoring and computer model validation.
Boyd, Matthew T.
2017-01-01
Three grid-connected monocrystalline silicon photovoltaic arrays have been instrumented with research-grade sensors on the Gaithersburg, MD campus of the National Institute of Standards and Technology (NIST). These arrays range from 73 kW to 271 kW and have different tilts, orientations, and configurations. Irradiance, temperature, wind, and electrical measurements at the arrays are recorded, and images are taken of the arrays to monitor shading and capture any anomalies. A weather station has also been constructed that includes research-grade instrumentation to measure all standard meteorological quantities plus additional solar irradiance spectral bands, full spectrum curves, and directional components using multiple irradiance sensor technologies. Reference photovoltaic (PV) modules are also monitored to provide comprehensive baseline measurements for the PV arrays. Images of the whole sky are captured, along with images of the instrumentation and reference modules to document any obstructions or anomalies. Nearly, all measurements at the arrays and weather station are sampled and saved every 1s, with monitoring having started on Aug. 1, 2014. This report describes the instrumentation approach used to monitor the performance of these photovoltaic systems, measure the meteorological quantities, and acquire the images for use in PV performance and weather monitoring and computer model validation. PMID:28670044
Woods, D E; Edge, M D; Colten, H R
1984-01-01
Complementary DNA (cDNA) clones corresponding to the major histocompatibility (MHC) class III antigen, complement protein C2, have been isolated from human liver cDNA libraries with the use of a complex mixture of synthetic oligonucleotides (17 mer) that contains 576 different oligonucleotide sequences. The C2 cDNA were used to identify a DNA restriction enzyme fragment length polymorphism that provides a genetic marker within the MHC that was not detectable at the protein level. An extensive search for genomic polymorphisms using a cDNA clone for another MHC class III gene, factor B, failed to reveal any DNA variants. The genomic variants detected with the C2 cDNA probe provide an additional genetic marker for analysis of MHC-linked diseases. Images PMID:6086718
NASA Astrophysics Data System (ADS)
Missaggia, Leo; Wang, Christine; Connors, Michael; Saar, Brian; Sanchez-Rubio, Antonio; Creedon, Kevin; Turner, George; Herzog, William
2016-03-01
There are a number of military and commercial applications for high-power laser systems in the mid-to-long-infrared wavelength range. By virtue of their demonstrated watt-level performance and wavelength diversity, quantum cascade laser (QCL) and amplifier devices are an excellent choice of emitter for those applications. To realize the power levels of interest, beam combining of arrays of these emitters is required and as a result, array technology must be developed. With this in mind, packaging and thermal management strategies were developed to facilitate the demonstration of a monolithic QCL array operating under CW conditions. Thermal models were constructed and simulations performed to determine the effect of parameters such as array-element ridge width and pitch on gain region temperature rise. The results of the simulations were considered in determining an appropriate QCL array configuration. State-of-the-art micro-impingement cooling along with an electrical distribution scheme comprised of AlN multi-layer technology were integrated into the design. The design of the module allows for individual electrical addressability of the array elements, a method of phase control demonstrated previously for coherent beam combining of diode arrays, along with access to both front and rear facets. Hence, both laser and single-pass amplifier arrays can be accommodated. A module was realized containing a 5 mm cavity length monolithic QCL array comprised of 7 elements on 450 m pitch. An output power of 3.16 W was demonstrated under CW conditions at an emission wavelength of 9μm.
NASA Technical Reports Server (NTRS)
Howell, Joe T.; O'Neill, Mark J.; Mankins, John C.
2006-01-01
Development is underway on a unique high-voltage, high energy solar concentrator array called Stretched Lens Array Square-Rigger (SLASR) for direct drive electric propulsion. The SLASR performance attributes closely match the critical needs of solar electric propulsion (SEP) systems, which may be used for space tugs to fuel efficiently transport cargo from low earth orbit (LEO) to low lunar orbit (LLO), in support of NASA's robotic and human exploration missions. Later SEP systems may similarly transport cargo from the earth-moon neighborhood to the Mars neighborhood. This paper will describe the SLASR technology, discuss SLASR developments and ground testing, and outline plans for future SLASR technology maturation.
NASA Technical Reports Server (NTRS)
Howell, Joe T.; O'Neill, Mark; Mankins, John C.
2006-01-01
Development is underway on a unique high-voltage, high-energy solar concentrator array called Stretched Lens Array Square-Rigger (SLASR) for direct drive electric propulsion. The SLASR performance attributes closely match the critical needs of solar electric propulsion (SEP) systems, which may be used for space tugs to fuel-efficiently transport cargo from low earth orbit (LEO) to low lunar orbit (LLO), in support of NASA s robotic and human exploration missions. Later SEP systems may similarly transport cargo from the earth-moon neighborhood to the Mars neighborhood. This paper will describe the SLASR technology, discuss SLASR developments and ground testing, and outline plans for future SLASR technology maturation.
The Photovoltaic Array Space Power plus Diagnostics (PASP Plus) Flight Experiment
NASA Technical Reports Server (NTRS)
Piszczor, Michael F.; Curtis, Henry B.; Guidice, Donald A.; Severance, Paul S.
1992-01-01
An overview of the Photovoltaic Array Space Power Plus Diagnostics (PASP Plus) flight experiment is presented in outline and graphic form. The goal of the experiment is to test a variety of photovoltaic cell and array technologies under various space environmental conditions. Experiment objectives, flight hardware, experiment control and diagnostic instrumentation, and illuminated thermal vacuum testing are addressed.
Kitahara, Hideaki; Tani, Masahiko; Hangyo, Masanori
2009-07-01
We developed a high-repetition-rate optical delay line based on a micromirror array and galvanometer mirror for terahertz time-domain spectroscopy. The micromirror array is fabricated by using the x-ray lithographic technology. The measurement of terahertz time-domain waveforms with the new optical delay line is demonstrated successfully up to 25 Hz.
MTF measurements with high-resolution a-Si:H imaging arrays
NASA Astrophysics Data System (ADS)
Yorkston, John; Antonuk, Larry E.; Seraji, N.; Huang, Weidong; Siewerdsen, Jeffrey H.; El-Mohri, Youcef
1995-05-01
Recent advances in a-Si:H fabrication technology have opened the way for the application of flat panel imaging arrays in a number of areas in medical imaging. Their large area (up to approximately 26 X 26 cm), thin profile (< 1 mm) and real time readout capability make them strong candidates for the replacement of more traditional x-ray imaging technologies such as film and image intensifier systems. As a first step towards a device suitable for clinical use we have created a 24.4 X 19.4 cm array with 127 micrometers pitch pixels. This device serves as a testbed for investigating the effects of design changes on array imaging performance. This paper reports on initial measurements of the spatial resolution of this device used in conjunction with an overlaying Lanex Regular screen and 90 kVp x rays. The measured pre-sampled modulation transfer function (p.s. MTF) is found to fall below the predicted value by up to approximately 8%. At least part of this reduction seems to be due to scattering of light photons between the array and the surface of the phosphor screen contacting the array.
Kim, Youngjo; Lam, Nguyen Dinh; Kim, Kangho; Kim, Sangin; Rotermund, Fabian; Lim, Hanjo; Lee, Jaejin
2012-07-01
Single-junction GaAs solar cell structures were grown by low-pressure MOCVD on GaAs (100) substrates. Micro-rod arrays with diameters of 2 microm, 5 microm, and 10 microm were fabricated on the surfaces of the GaAs solar cells via photolithography and wet chemical etching. The patterned surfaces were coated with Au nanoparticles using an Au colloidal solution. Characteristics of the GaAs solar cells with and without the micro-rod arrays and Au nanoparticles were investigated. The short-circuit current density of the GaAs solar cell with 2 microm rod arrays and Au nanoparticles increased up to 34.9% compared to that of the reference cell without micro-rod arrays and Au nanoparticles. The conversion efficiency of the GaAs solar cell that was coated with Au nanoparticles on the patterned surface with micro-rod arrays can be improved from 14.1% to 19.9% under 1 sun AM 1.5G illumination. These results show that micro-rod arrays and Au nanoparticle coating can be applied together in surface patterning to achieve a novel cost-effective anti-reflection technology.
NASA Technical Reports Server (NTRS)
1986-01-01
Emerging satellite designs require increasing amounts of electrical power to operate spacecraft instruments and to provide environments suitable for human habitation. In the past, electrical power was generated by covering rigid honeycomb panels with solar cells. This technology results in unacceptable weight and volume penalties when large amounts of power are required. To fill the need for large-area, lightweight solar arrays, a fabrication technique in which solar cells are attached to a copper printed circuit laminated to a plastic sheet was developed. The result is a flexible solar array with one-tenth the stowed volume and one-third the weight of comparably sized rigid arrays. An automated welding process developed to attack the cells to the printed circuit guarantees repeatable welds that are more tolerant of severe environments than conventional soldered connections. To demonstrate the flight readiness of this technology, the Solar Array Flight Experiment (SAFE) was developed and flown on the space shuttle Discovery in September 1984. The tests showed the modes and frequencies of the array to be very close to preflight predictions. Structural damping, however, was higher than anticipated. Electrical performance of the active solar panel was also tested. The flight performance and postflight data evaluation are described.
Development of FIR arrays with integrating amplifiers
NASA Technical Reports Server (NTRS)
Young, Erick T.
1988-01-01
The development of optimized photoconductor arrays suitable for far infrared space astronomical applications are described. Although the primary impetus is the production of a 16 by 16 element Ge:Ga demonstration array for SIRTF, the extension of this technology to Large Deployable Reflector (LDR) is considered. The optimization of Ge:Ga and Ge:Be photoconductor materials is discussed. In collaboration with Lawrence Berkeley Laboratory, measurements of FIR photoconductors with quantum efficiencies greater than 20 percent at 100 micrometers, and dark currents below 300 electrons/s are presented. Integrating J-FET amplifier technology is discussed. The current generation of integrating amplifiers has a demonstrated read noise of less than 20 electrons for an integration time of 100 s. The design is shown for a stackable 16 x n Ge:Ga array that utilizes a 16-channel monolithic version of the J-FET integrator. A part of the design is the use of a thin, thermally insulating substrate that allows the electronics to operate at the optimum temperature of 50 K while maintaining thermal and optical isolation from the detectors at 2 K. The power dissipation for the array is less than 16 mW. The array design may particularly be applicable to high resolution imaging spectrometers for LDR.
Development of FIR arrays with integrating amplifiers
NASA Astrophysics Data System (ADS)
Young, Erick T.
1988-08-01
The development of optimized photoconductor arrays suitable for far infrared space astronomical applications are described. Although the primary impetus is the production of a 16 by 16 element Ge:Ga demonstration array for SIRTF, the extension of this technology to Large Deployable Reflector (LDR) is considered. The optimization of Ge:Ga and Ge:Be photoconductor materials is discussed. In collaboration with Lawrence Berkeley Laboratory, measurements of FIR photoconductors with quantum efficiencies greater than 20 percent at 100 micrometers, and dark currents below 300 electrons/s are presented. Integrating J-FET amplifier technology is discussed. The current generation of integrating amplifiers has a demonstrated read noise of less than 20 electrons for an integration time of 100 s. The design is shown for a stackable 16 x n Ge:Ga array that utilizes a 16-channel monolithic version of the J-FET integrator. A part of the design is the use of a thin, thermally insulating substrate that allows the electronics to operate at the optimum temperature of 50 K while maintaining thermal and optical isolation from the detectors at 2 K. The power dissipation for the array is less than 16 mW. The array design may particularly be applicable to high resolution imaging spectrometers for LDR.
NASA Technical Reports Server (NTRS)
Daiello, R. V.
1977-01-01
A general technology assessment and manufacturing cost analysis was presented. A near-term (1982) factory design is described, and the results of an experimental production study for the large-scale production of flat-panel silicon and solar-cell arrays are detailed.
An Active K-Band Receive Slot Array for Mobile Satellite Communications
NASA Technical Reports Server (NTRS)
Tulintseff, A. N.; Lee, K. A.; Sukamto, L. M.; Chew, W.
1994-01-01
An active receive slot array has been developed for operation in the downlink frequency band, 19.914-20.064 GHz, of NASA's Advanced Communication Technology Satellite (ACTS) for the ACTS Mobile Terminal (AMT) project.
Flat-plate solar array project. Volume 1: Executive summary
NASA Technical Reports Server (NTRS)
Callaghan, W.; Mcdonald, R.
1986-01-01
In 1975, the U.S. Government contracted the Jet Propulsion Lab. to develop, by 1985, in conjunction with industry, the photovoltaics (PV) module and array technology required for widespread use of photovoltaics as a significant terrestrial energy source. As a result, a project that eventually became known as the Flat Plate Solar Array (FSA) Project was formed to manage an industry, university, and Government team to perform the necessary research and development. The original goals were to achieve widespread commercial use of PV modules and arrays through the development of technology that would allow them to be profitably sold for $1.07/peak watts (1985 dollars). A 10% module conversion efficiency and a 20 year lifetime were also goals. It is intended that the executive summary provide the means by which one can gain a perspective on 11 years of terrestrial photovoltaic research and development conducted by the FSA Project.
SCARLET development, fabrication and testing for the Deep Space 1 spacecraft
DOE Office of Scientific and Technical Information (OSTI.GOV)
Murphy, D.M.; Allen, D.M.
1997-12-31
An advanced version of ``Solar Concentrator Arrays with Refractive Linear Element Technology`` (SCARLET) is being assembled for use on the first NASA/JPL New Millennium spacecraft: Deep Space 1 (DS1). The array is scaled up from the first SCARLET array that was built for the METEOR satellite in 1995 and incorporates advanced technologies such as dual-junction solar cells and an improved structural design. Due to the failure of the Conestoga launch vehicle, this will be the first flight of a modular concentrator array. SCARLET will provide 2.6 kW to the DS1 spacecraft to be launched in July 1998 for a missionmore » that includes fly-bys of the asteroid McAuliffe, Mars, and the comet West-Kohoutek-Ikemura. This paper describes the SCARLET design, fabrication/assembly, and testing program for the flight system.« less
Technology Development for AGIS (Advanced Gamma-ray Imaging System).
NASA Astrophysics Data System (ADS)
Krennrich, Frank
2008-04-01
Next-generation arrays of atmospheric Cherenkov telescopes are at the conceptual planning stage and each could consist of on the order of 100 telescopes. The two currently-discussed projects AGIS in the US and CTA in Europe, have the potential to achieve an order of magnitude better sensitivity for Very High Energy (VHE) gamma-ray observations over state-to-the-art observatories. These projects require a substantial increase in scale from existing 4-telescope arrays such as VERITAS and HESS. The optimization of a large array requires exploring cost reduction and research and development for the individual elements while maximizing their performance as an array. In this context, the technology development program for AGIS will be discussed. This includes developing new optical designs, evaluating new types of photodetectors, developing fast trigger systems, integrating fast digitizers into highly-pixilated cameras, and reliability engineering of the individual components.
System design of ELITE power processing unit
NASA Astrophysics Data System (ADS)
Caldwell, David J.
The Electric Propulsion Insertion Transfer Experiment (ELITE) is a space mission planned for the mid 1990s in which technological readiness will be demonstrated for electric orbit transfer vehicles (EOTVs). A system-level design of the power processing unit (PPU), which conditions solar array power for the arcjet thruster, was performed to optimize performance with respect to reliability, power output, efficiency, specific mass, and radiation hardness. The PPU system consists of multiphased parallel switchmode converters, configured as current sources, connected directly from the array to the thruster. The PPU control system includes a solar array peak power tracker (PPT) to maximize the power delivered to the thruster regardless of variations in array characteristics. A stability analysis has been performed to verify that the system is stable despite the nonlinear negative impedance of the PPU input and the arcjet thruster. Performance specifications are given to provide the required spacecraft capability with existing technology.
Construction, database integration, and application of an Oenothera EST library.
Mrácek, Jaroslav; Greiner, Stephan; Cho, Won Kyong; Rauwolf, Uwe; Braun, Martha; Umate, Pavan; Altstätter, Johannes; Stoppel, Rhea; Mlcochová, Lada; Silber, Martina V; Volz, Stefanie M; White, Sarah; Selmeier, Renate; Rudd, Stephen; Herrmann, Reinhold G; Meurer, Jörg
2006-09-01
Coevolution of cellular genetic compartments is a fundamental aspect in eukaryotic genome evolution that becomes apparent in serious developmental disturbances after interspecific organelle exchanges. The genus Oenothera represents a unique, at present the only available, resource to study the role of the compartmentalized plant genome in diversification of populations and speciation processes. An integrated approach involving cDNA cloning, EST sequencing, and bioinformatic data mining was chosen using Oenothera elata with the genetic constitution nuclear genome AA with plastome type I. The Gene Ontology system grouped 1621 unique gene products into 17 different functional categories. Application of arrays generated from a selected fraction of ESTs revealed significantly differing expression profiles among closely related Oenothera species possessing the potential to generate fertile and incompatible plastid/nuclear hybrids (hybrid bleaching). Furthermore, the EST library provides a valuable source of PCR-based polymorphic molecular markers that are instrumental for genotyping and molecular mapping approaches.
Unique inflammatory RNA profiles of microglia in Creutzfeldt-Jakob disease
NASA Astrophysics Data System (ADS)
Baker, Christopher A.; Manuelidis, Laura
2003-01-01
Previous studies in Creutzfeldt-Jakob disease (CJD) have shown that myeloid cells in the periphery as well as derivative microglial cells in the brain are infectious. Microglia can show an activated phenotype before prion protein (PrP) pathology is detectable in brain, and isolated infectious microglia contain very little PrP. To find whether a set of inflammatory genes are significantly induced or suppressed with infection, we analyzed RNA from isolated microglia with relevant cDNA arrays, and identified 30 transcripts not previously examined in any transmissible spongiform encephalopathy. This CJD expression profile contrasted with that of uninfected microglia exposed to prototypic inflammatory stimuli such as lipopolysaccharide and IFN-, as well as PrP amyloid. These findings underscore inflammatory pathways evoked by the infectious agent in brain. Transcript profiles unique for CJD microglia and other myeloid cells provide opportunities for more sensitive preclinical diagnoses of infectious and noninfectious neurodegenerative diseases.
Identification of genes regulated during mechanical load-induced cardiac hypertrophy
NASA Technical Reports Server (NTRS)
Johnatty, S. E.; Dyck, J. R.; Michael, L. H.; Olson, E. N.; Abdellatif, M.; Schneider, M. (Principal Investigator)
2000-01-01
Cardiac hypertrophy is associated with both adaptive and adverse changes in gene expression. To identify genes regulated by pressure overload, we performed suppressive subtractive hybridization between cDNA from the hearts of aortic-banded (7-day) and sham-operated mice. In parallel, we performed a subtraction between an adult and a neonatal heart, for the purpose of comparing different forms of cardiac hypertrophy. Sequencing more than 100 clones led to the identification of an array of functionally known (70%) and unknown genes (30%) that are upregulated during cardiac growth. At least nine of those genes were preferentially expressed in both the neonatal and pressure over-load hearts alike. Using Northern blot analysis to investigate whether some of the identified genes were upregulated in the load-independent calcineurin-induced cardiac hypertrophy mouse model, revealed its incomplete similarity with the former models of cardiac growth. Copyright 2000 Academic Press.
AAV-mediated in vivo functional selection of tissue-protective factors against ischaemia
Ruozi, Giulia; Bortolotti, Francesca; Falcione, Antonella; Dal Ferro, Matteo; Ukovich, Laura; Macedo, Antero; Zentilin, Lorena; Filigheddu, Nicoletta; Cappellari, Gianluca Gortan; Baldini, Giovanna; Zweyer, Marina; Barazzoni, Rocco; Graziani, Andrea; Zacchigna, Serena; Giacca, Mauro
2015-01-01
Functional screening of expression libraries in vivo would offer the possibility of identifying novel biotherapeutics without a priori knowledge of their biochemical function. Here we describe a procedure for the functional selection of tissue-protective factors based on the in vivo delivery of arrayed cDNA libraries from the mouse secretome using adeno-associated virus (AAV) vectors. Application of this technique, which we call FunSel, in the context of acute ischaemia, revealed that the peptide ghrelin protects skeletal muscle and heart from ischaemic damage. When delivered to the heart using an AAV9 vector, ghrelin markedly reduces infarct size and preserves cardiac function over time. This protective activity associates with the capacity of ghrelin to sustain autophagy and remove dysfunctional mitochondria after myocardial infarction. Our findings describe an innovative tool to identify biological therapeutics and reveal a novel role of ghrelin as an inducer of myoprotective autophagy. PMID:26066847
Procedure for normalization of cDNA libraries
Bonaldo, M.D.; Soares, M.B.
1997-12-30
This invention provides a method to normalize a cDNA library constructed in a vector capable of being converted to single-stranded circles and capable of producing complementary nucleic acid molecules to the single-stranded circles comprising: (a) converting the cDNA library in single-stranded circles; (b) generating complementary nucleic acid molecules to the single-stranded circles; (c) hybridizing the single-stranded circles converted in step (a) with complementary nucleic acid molecules of step (b) to produce partial duplexes to an appropriate Cot; (e) separating the unhybridized single-stranded circles from the hybridized single-stranded circles, thereby generating a normalized cDNA library. 1 fig.
LaPolla, R J; Mayne, K M; Davidson, N
1984-01-01
A mouse cDNA clone has been isolated that contains the complete coding region of a protein highly homologous to the delta subunit of the Torpedo acetylcholine receptor (AcChoR). The cDNA library was constructed in the vector lambda 10 from membrane-associated poly(A)+ RNA from BC3H-1 mouse cells. Surprisingly, the delta clone was selected by hybridization with cDNA encoding the gamma subunit of the Torpedo AcChoR. The nucleotide sequence of the mouse cDNA clone contains an open reading frame of 520 amino acids. This amino acid sequence exhibits 59% and 50% sequence homology to the Torpedo AcChoR delta and gamma subunits, respectively. However, the mouse nucleotide sequence has several stretches of high homology with the Torpedo gamma subunit cDNA, but not with delta. The mouse protein has the same general structural features as do the Torpedo subunits. It is encoded by a 3.3-kilobase mRNA. There is probably only one, but at most two, chromosomal genes coding for this or closely related sequences. Images PMID:6096870
Carow, Katrin; Read, Christina; Häfner, Norman; Runnebaum, Ingo B; Corner, Adam; Dürst, Matthias
2017-10-30
Qualitative analyses showed that the presence of HPV mRNA in sentinel lymph nodes of cervical cancer patients with pN0 status is associated with significantly decreased recurrence free survival. To further address the clinical potential of the strategy and to define prognostic threshold levels it is necessary to use a quantitative assay. Here, we compare two methods of quantification: digital PCR and standard quantitative PCR. Serial dilutions of 5 ng-5 pg RNA (≙ 500-0.5 cells) of the cervical cancer cell line SiHa were prepared in 5 µg RNA of the HPV-negative human keratinocyte cell line HaCaT. Clinical samples consisted of 10 sentinel lymph nodes with varying HPV transcript levels. Reverse transcription of total RNA (5 µg RNA each) was performed in 100 µl and cDNA aliquots were analyzed by qPCR and dPCR. Digital PCR was run in the RainDrop ® Digital PCR system (RainDance Technologies) using a probe-based detection of HPV E6/E7 cDNA PCR products with 11 µl template. qPCR was done using a Rotor Gene Q 5plex HRM (Qiagen) amplifying HPV E6/E7 cDNA in a SYBR Green format with 1 µl template. For the analysis of both, clinical samples and serial dilution samples, dPCR and qPCR showed comparable sensitivity. With regard to reproducibility, both methods differed considerably, especially for low template samples. Here, we found with qPCR a mean variation coefficient of 126% whereas dPCR enabled a significantly lower mean variation coefficient of 40% (p = 0.01). Generally, we saw with dPCR a substantial reduction of subsampling errors, which most likely reflects the large cDNA amounts available for analysis. Compared to real-time PCR, dPCR shows higher reliability. Thus, our HPV mRNA dPCR assay holds promise for the clinical evaluation of occult tumor cells in histologically tumor-free lymph nodes in future studies.
From biomedicine to natural history research: EST resources for ambystomatid salamanders
Putta, Srikrishna; Smith, Jeramiah J; Walker, John A; Rondet, Mathieu; Weisrock, David W; Monaghan, James; Samuels, Amy K; Kump, Kevin; King, David C; Maness, Nicholas J; Habermann, Bianca; Tanaka, Elly; Bryant, Susan V; Gardiner, David M; Parichy, David M; Voss, S Randal
2004-01-01
Background Establishing genomic resources for closely related species will provide comparative insights that are crucial for understanding diversity and variability at multiple levels of biological organization. We developed ESTs for Mexican axolotl (Ambystoma mexicanum) and Eastern tiger salamander (A. tigrinum tigrinum), species with deep and diverse research histories. Results Approximately 40,000 quality cDNA sequences were isolated for these species from various tissues, including regenerating limb and tail. These sequences and an existing set of 16,030 cDNA sequences for A. mexicanum were processed to yield 35,413 and 20,599 high quality ESTs for A. mexicanum and A. t. tigrinum, respectively. Because the A. t. tigrinum ESTs were obtained primarily from a normalized library, an approximately equal number of contigs were obtained for each species, with 21,091 unique contigs identified overall. The 10,592 contigs that showed significant similarity to sequences from the human RefSeq database reflected a diverse array of molecular functions and biological processes, with many corresponding to genes expressed during spinal cord injury in rat and fin regeneration in zebrafish. To demonstrate the utility of these EST resources, we searched databases to identify probes for regeneration research, characterized intra- and interspecific nucleotide polymorphism, saturated a human – Ambystoma synteny group with marker loci, and extended PCR primer sets designed for A. mexicanum / A. t. tigrinum orthologues to a related tiger salamander species. Conclusions Our study highlights the value of developing resources in traditional model systems where the likelihood of information transfer to multiple, closely related taxa is high, thus simultaneously enabling both laboratory and natural history research. PMID:15310388
ROTH, STEPHEN M.; FERRELL, ROBERT E.; PETERS, DAVID G.; METTER, E. JEFFREY; HURLEY, BEN F.; ROGERS, MARC A.
2010-01-01
The purpose of this study was to determine the influence of age, sex, and strength training (ST) on large-scale gene expression patterns in vastus lateralis muscle biopsies using high-density cDNA microarrays and quantitative PCR. Muscle samples from sedentary young (20–30 yr) and older (65–75 yr) men and women (5 per group) were obtained before and after a 9-wk unilateral heavy resistance ST program. RNA was hybridized to cDNA filter microarrays representing ~4,000 known human genes and comparisons were made among arrays to determine differential gene expression as a result of age and sex differences, and/or response to ST. Sex had the strongest influence on muscle gene expression, with differential expression (>1.7-fold) observed for ~200 genes between men and women (~75% with higher expression in men). Age contributed to differential expression as well, as ~50 genes were identified as differentially expressed (>1.7-fold) in relation to age, representing structural, metabolic, and regulatory gene classes. Sixty-nine genes were identified as being differentially expressed (>1.7-fold) in all groups in response to ST, and the majority of these were downregulated. Quantitative PCR was employed to validate expression levels for caldesmon, SWI/SNF (BAF60b), and four-and-a-half LIM domains 1. These significant differences suggest that in the analysis of skeletal muscle gene expression issues of sex, age, and habitual physical activity must be addressed, with sex being the most critical variable. PMID:12209020
The SCARLET{trademark} array for high power GEO satellites
DOE Office of Scientific and Technical Information (OSTI.GOV)
Spence, B.R.; Jones, P.A.; Eskenazi, M.I.
1997-12-31
The GEO satellite market is demanding increasingly capable spacecraft which, in turn, drives commercial spacecraft manufacturers to require significantly higher power solar arrays. As satellite capability increases the demand for high power array systems which are both cost and performance competitive becomes more crucial. Conventional rigid panel planar arrays, although suitable in the past, negatively impact spacecraft competitiveness for these new applications. The Solar Concentrator Array with Refractive Linear Element Technology (SCARLET{trademark}) represents an economically attractive solution for meeting these new high power requirements. When compared to conventional planar arrays, SCARLET provides substantially lower cost and higher deployed stiffness, competitivemore » mass, better producibility, and affordable use of high efficiency multijunction cells. This paper compares cost/performance characteristics of the SCARLET array to conventional planar arrays for high power GEO spacecraft applications. High power SCARLET array configurations are described, and inherent spacecraft and array level cost/performance benefits are presented.« less
Code of Federal Regulations, 2012 CFR
2012-07-01
.... (c) Critical Technology. Technologies that consist of (1) arrays of design and manufacturing know-how... militarily critical technology). (d) Other legitimate business purposes. Include: (1) Providing or seeking to provide equipment or technology to a foreign government with the approval of the U.S. Government (for...
Code of Federal Regulations, 2013 CFR
2013-07-01
.... (c) Critical Technology. Technologies that consist of (1) arrays of design and manufacturing know-how... militarily critical technology). (d) Other legitimate business purposes. Include: (1) Providing or seeking to provide equipment or technology to a foreign government with the approval of the U.S. Government (for...
Code of Federal Regulations, 2011 CFR
2011-07-01
.... (c) Critical Technology. Technologies that consist of (1) arrays of design and manufacturing know-how... militarily critical technology). (d) Other legitimate business purposes. Include: (1) Providing or seeking to provide equipment or technology to a foreign government with the approval of the U.S. Government (for...
Code of Federal Regulations, 2014 CFR
2014-07-01
.... (c) Critical Technology. Technologies that consist of (1) arrays of design and manufacturing know-how... militarily critical technology). (d) Other legitimate business purposes. Include: (1) Providing or seeking to provide equipment or technology to a foreign government with the approval of the U.S. Government (for...
Fujiwara, Mikio; Hirao, Takanori; Kawada, Mitsunobu; Shibai, Hiroshi; Matsuura, Shuji; Kaneda, Hidehiro; Patrashin, Mikhail; Nakagawa, Takao
2003-04-20
To our knowledge, we are the first to successfully report a direct hybrid two-dimensional (2D) detector array in the far-infrared region. Gallium-doped germanium (Ge:Ga) has been used extensively to produce sensitive far-infrared detectors with a cutoff wavelength of approximately equal to 110 microm (2.7 THz). It is widely used in the fields of astronomy and molecular and solid spectroscopy. However, Ge:Ga photoconductors must be cooled below 4.2 K to reduce thermal noise, and this operating condition makes it difficult to develop a large format array because of the need for a warm amplifier. Development of Ge:Ga photoconductor arrays to take 2D terahertz images is now an important target in such research fields as space astronomy. We present the design of a 20 x 3 Ge:Ga far-infrared photoconductor array directly hybridized to a Si p-type metal-oxide-semiconductor readout integrated circuit using indium-bump technology. The main obstacles in creating this 2D array were (1) fabricating a monolithic Ge:Ga 2D array with a longitudinal configuration, (2) developing a cryogenic capacitive transimpedance amplifer, and (3) developing a technology for connecting the detector to the electronics. With this technology, a prototype Ge:Ga photoconductor with a direct hybrid structure has shown a responsivity as high as 14.6 A/W and a minimum detectable power of 5.6 x 10(-17) W for an integration time of 0.14 s when it was cooled to 2.1 K. Its noise is limited by the readout circuit with 20 microV/Hz(1/2) at 1 Hz. Vibration and cooling tests demonstrated that this direct hybrid structure is strong enough for spaceborne instruments. This detector array will be installed on the Japanese infrared satellite ASTRO-F.
Selby, Thomas H.; Hart, Kristen M.; Fujisaki, Ikuko; Smith, Brian J.; Pollock, Clayton J; Hillis-Star, Zandy M; Lundgren, Ian; Oli, Madan K.
2016-01-01
Submerged passive acoustic technology allows researchers to investigate spatial and temporal movement patterns of many marine and freshwater species. The technology uses receivers to detect and record acoustic transmissions emitted from tags attached to an individual. Acoustic signal strength naturally attenuates over distance, but numerous environmental variables also affect the probability a tag is detected. Knowledge of receiver range is crucial for designing acoustic arrays and analyzing telemetry data. Here, we present a method for testing a relatively large-scale receiver array in a dynamic Caribbean coastal environment intended for long-term monitoring of multiple species. The U.S. Geological Survey and several academic institutions in collaboration with resource management at Buck Island Reef National Monument (BIRNM), off the coast of St. Croix, recently deployed a 52 passive acoustic receiver array. We targeted 19 array-representative receivers for range-testing by submersing fixed delay interval range-testing tags at various distance intervals in each cardinal direction from a receiver for a minimum of an hour. Using a generalized linear mixed model (GLMM), we estimated the probability of detection across the array and assessed the effect of water depth, habitat, wind, temperature, and time of day on the probability of detection. The predicted probability of detection across the entire array at 100 m distance from a receiver was 58.2% (95% CI: 44.0–73.0%) and dropped to 26.0% (95% CI: 11.4–39.3%) 200 m from a receiver indicating a somewhat constrained effective detection range. Detection probability varied across habitat classes with the greatest effective detection range occurring in homogenous sand substrate and the smallest in high rugosity reef. Predicted probability of detection across BIRNM highlights potential gaps in coverage using the current array as well as limitations of passive acoustic technology within a complex coral reef environment.
Achieving ultra-high temperatures with a resistive emitter array
NASA Astrophysics Data System (ADS)
Danielson, Tom; Franks, Greg; Holmes, Nicholas; LaVeigne, Joe; Matis, Greg; McHugh, Steve; Norton, Dennis; Vengel, Tony; Lannon, John; Goodwin, Scott
2016-05-01
The rapid development of very-large format infrared detector arrays has challenged the IR scene projector community to also develop larger-format infrared emitter arrays to support the testing of systems incorporating these detectors. In addition to larger formats, many scene projector users require much higher simulated temperatures than can be generated with current technology in order to fully evaluate the performance of their systems and associated processing algorithms. Under the Ultra High Temperature (UHT) development program, Santa Barbara Infrared Inc. (SBIR) is developing a new infrared scene projector architecture capable of producing both very large format (>1024 x 1024) resistive emitter arrays and improved emitter pixel technology capable of simulating very high apparent temperatures. During earlier phases of the program, SBIR demonstrated materials with MWIR apparent temperatures in excess of 1400 K. New emitter materials have subsequently been selected to produce pixels that achieve even higher apparent temperatures. Test results from pixels fabricated using the new material set will be presented and discussed. A 'scalable' Read In Integrated Circuit (RIIC) is also being developed under the same UHT program to drive the high temperature pixels. This RIIC will utilize through-silicon via (TSV) and Quilt Packaging (QP) technologies to allow seamless tiling of multiple chips to fabricate very large arrays, and thus overcome the yield limitations inherent in large-scale integrated circuits. Results of design verification testing of the completed RIIC will be presented and discussed.
Study of solar array switching power management technology for space power system
NASA Technical Reports Server (NTRS)
Cassinelli, J. E.
1982-01-01
This report documents work performed on the Solar Array Switching Power Management Study. Mission characteristics for three missions were defined to the depth necessary to determine their power management requirements. Solar array switching concepts were identified that could safisfy the mission requirements. These switching concepts were compared with a conventional buck regulator system on the basis of cost, weight and volume, reliability, efficiency and thermal control. For the missions reviewed, solar array switching provided significant advantages in all areas of comparison.
LSA Low-cost Solar Array project
NASA Technical Reports Server (NTRS)
1978-01-01
The activities of the Low-Cost Silicon Solar Array Project during the period October through December, 1977 are reported. The LSSA Project is assigned responsibility for advancing silicon solar array technology while encouraging industry to reduce the price of arrays to a level at which photovoltaic electric power systems will be competitive with more conventional power sources early in the next decade. Set forth are the goals and plans with which the Project intends to accomplish this and the progress that was made during the quarter.
Study of solar array switching power management technology for space power system
NASA Technical Reports Server (NTRS)
Cassinelli, J. E.
1982-01-01
This report documents work performed on the Solar Array Switching Power Management Study. Mission characteristics for three missions were defined to the depth necessary to determine their power management requirements. Solar array switching concepts which could satisfy the mission requirements were identified. The switching concepts were compared with a conventional buck regulator system for cost, weight and volume, reliability, efficiency and thermal control. Solar array switching provided significant advantages in all areas of comparison for the reviewed missions.
Low-cost Solar Array (LSA) project
NASA Technical Reports Server (NTRS)
1978-01-01
The activities of the Low-Cost Solar Array Project are described for the period April through June 1978. The Project is assigned responsibility for advancing solar array technology while encouraging industry to reduce the price of arrays to a level at which photovoltaic electric power systems will be competitive with more conventional power sources early in the next decade. Set forth are the goals and plans with which the Project intends to accomplish this and the progress that was made during the quarter.
The evolution and exploitation of the fiber-optic hydrophone
NASA Astrophysics Data System (ADS)
Hill, David J.
2007-07-01
In the late 1970s one of the first applications identified for fibre-optic sensing was the fibre-optic hydrophone. It was recognised that the technology had the potential to provide a cost effective solution for large-scale arrays of highly sensitive hydrophones which could be interrogated over large distances. Consequently both the United Kingdom and United States navies funded the development of this sonar technology to the point that it is now deployed on submarines and as seabed arrays. The basic design of a fibre-optic hydrophone has changed little; comprising a coil of optical fibre wound on a compliant mandrel, interrogated using interferometric techniques. Although other approaches are being investigated, including the development of fibre-laser hydrophones, the interferometric approach remains the most efficient way to create highly multiplexed arrays of acoustic sensors. So much so, that the underlying technology is now being exploited in civil applications. Recently the exploration and production sector of the oil and gas industry has begun funding the development of fibre-optic seismic sensing using seabed mounted, very large-scale arrays of four component (three accelerometers and a hydrophone) packages based upon the original technology developed for sonar systems. This has given new impetus to the development of the sensors and the associated interrogation systems which has led to the technology being adopted for other commercial uses. These include the development of networked in-road fibre-optic Weigh-in-Motion sensors and of intruder detection systems which are able to acoustically monitor long lengths of border, on both land and at sea. After two decades, the fibre-optic hydrophone and associated technology has matured and evolved into a number of highly capable sensing solutions used by a range of industries.
Cloning, sequencing, and expression of cDNA for human. beta. -glucuronidase
DOE Office of Scientific and Technical Information (OSTI.GOV)
Oshima, A.; Kyle, J.W.; Miller, R.D.
1987-02-01
The authors report here the cDNA sequence for human placental ..beta..-glucuronidase (..beta..-D-glucuronoside glucuronosohydrolase, EC 3.2.1.31) and demonstrate expression of the human enzyme in transfected COS cells. They also sequenced a partial cDNA clone from human fibroblasts that contained a 153-base-pair deletion within the coding sequence and found a second type of cDNA clone from placenta that contained the same deletion. Nuclease S1 mapping studies demonstrated two types of mRNAs in human placenta that corresponded to the two types of cDNA clones isolated. The NH/sub 2/-terminal amino acid sequence determined for human spleen ..beta..-glucuronidase agreed with that inferred from the DNAmore » sequence of the two placental clones, beginning at amino acid 23, suggesting a cleaved signal sequence of 22 amino acids. When transfected into COS cells, plasmids containing either placental clone expressed an immunoprecipitable protein that contained N-linked oligosaccharides as evidenced by sensitivity to endoglycosidase F. However, only transfection with the clone containing the 153-base-pair segment led to expression of human ..beta..-glucuronidase activity. These studies provide the sequence for the full-length cDNA for human ..beta..-glucuronidase, demonstrate the existence of two populations of mRNA for ..beta..-glucuronidase in human placenta, only one of which specifies a catalytically active enzyme, and illustrate the importance of expression studies in verifying that a cDNA is functionally full-length.« less
In situ synthesis of protein arrays.
He, Mingyue; Stoevesandt, Oda; Taussig, Michael J
2008-02-01
In situ or on-chip protein array methods use cell free expression systems to produce proteins directly onto an immobilising surface from co-distributed or pre-arrayed DNA or RNA, enabling protein arrays to be created on demand. These methods address three issues in protein array technology: (i) efficient protein expression and availability, (ii) functional protein immobilisation and purification in a single step and (iii) protein on-chip stability over time. By simultaneously expressing and immobilising many proteins in parallel on the chip surface, the laborious and often costly processes of DNA cloning, expression and separate protein purification are avoided. Recently employed methods reviewed are PISA (protein in situ array) and NAPPA (nucleic acid programmable protein array) from DNA and puromycin-mediated immobilisation from mRNA.
2016-09-23
Acquisition and Data Analysis). EMI sensors, MetalMapper, man-portable Time-domain Electromagnetic Multi-sensor Towed Array Detection System (TEMTADS...California Department of Toxic Substances Control EM61 EM61-MK2 EMI electromagnetic induction ESTCP Environmental Security Technology Certification...SOP Standard Operating Procedure v TEMTADS Time-domain Electromagnetic Multi-sensor Towed Array Detection System man-portable 2x2 TOI target(s
NASA Astrophysics Data System (ADS)
Hatano, Kaoru; Chida, Akihiro; Okano, Tatsuya; Sugisawa, Nozomu; Inoue, Tatsunori; Seo, Satoshi; Suzuki, Kunihiko; Oikawa, Yoshiaki; Miyake, Hiroyuki; Koyama, Jun; Yamazaki, Shunpei; Eguchi, Shingo; Katayama, Masahiro; Sakakura, Masayuki
2011-03-01
In this paper, we report a 3.4-in. flexible active matrix organic light emitting display (AMOLED) display with remarkably high definition (quarter high definition: QHD) in which oxide thin film transistors (TFTs) are used. We have developed a transfer technology in which a TFT array formed on a glass substrate is separated from the substrate by physical force and then attached to a flexible plastic substrate. Unlike a normal process in which a TFT array is directly fabricated on a thin plastic substrate, our transfer technology permits a high integration of high performance TFTs, such as low-temperature polycrystalline silicon TFTs (LTPS TFTs) and oxide TFTs, on a plastic substrate, because a flat, rigid, and thermally-stable glass substrate can be used in the TFT fabrication process in our transfer technology. As a result, this technology realized an oxide TFT array for an AMOLED on a plastic substrate. Furthermore, in order to achieve a high-definition AMOLED, color filters were incorporated in the TFT array and a white organic light-emitting diode (OLED) was combined. One of the features of this device is that the whole body of the device can be bent freely because a source driver and a gate driver can be integrated on the substrate due to the high mobility of an oxide TFT. This feature means “true” flexibility.
1999-04-20
NASA's Space Optics Manufacturing Technology Center has been working to expand our view of the universe via sophisticated new telescopes. The Optics Center's goal is to develop low-cost, advanced space optics technologies for the NASA program in the 21st century, including the long-term goal of imaging Earth-like planets in distant solar systems. A segmented array of mirrors was designed by the Space Optics Manufacturing Technology Center for the solar concentrator test stand at the Marshall Space Flight Center (MSFC) for powering solar thermal propulsion engines. Each hexagon mirror has a spherical surface to approximate a parabolic concentrator when combined into the entire 18-foot diameter array. The aluminum mirrors were polished with a diamond turning machine that creates a glass-like reflective finish on metal. The precision fabrication machinery at the Space Optics Manufacturing Technology Center at MSFC can polish specialized optical elements to a world class quality of smoothness. This image shows optics physicist, Vince Huegele, examining one of the 144-segment hexagonal mirrors of the 18-foot diameter array at the MSFC solar concentrator test stand.
1999-04-20
NASA's Space Optics Manufacturing Technology Center has been working to expand our view of the universe via sophisticated new telescopes. The Optics Center's goal is to develop low-cost, advanced space optics technologies for the NASA program in the 21st century, including the long-term goal of imaging Earth-like planets in distant solar systems. A segmented array of mirrors was designed by the Space Optics Manufacturing Technology Center for solar the concentrator test stand at the Marshall Space Flight Center (MSFC) for powering solar thermal propulsion engines. Each hexagon mirror has a spherical surface to approximate a parabolic concentrator when combined into the entire 18-foot diameter array. The aluminum mirrors were polished with a diamond turning machine, that creates a glass-like reflective finish on metal. The precision fabrication machinery at the Space Optics Manufacturing Technology Center at MSFC can polish specialized optical elements to a world class quality of smoothness. This image shows optics physicist, Vince Huegele, examining one of the 144-segment hexagonal mirrors of the 18-foot diameter array at the MSFC solar concentrator test stand.
Advances in lenticular lens arrays for visual display
NASA Astrophysics Data System (ADS)
Johnson, R. Barry; Jacobsen, Gary A.
2005-08-01
Lenticular lens arrays are widely used in the printed display industry and in specialized applications of electronic displays. In general, lenticular arrays can create from interlaced printed images such visual effects as 3-D, animation, flips, morph, zoom, or various combinations. The use of these typically cylindrical lens arrays for this purpose began in the late 1920's. The lenses comprise a front surface having a spherical crosssection and a flat rear surface upon where the material to be displayed is proximately located. The principal limitation to the resultant image quality for current technology lenticular lenses is spherical aberration. This limitation causes the lenticular lens arrays to be generally thick (0.5 mm) and not easily wrapped around such items as cans or bottles. The objectives of this research effort were to develop a realistic analytical model, to significantly improve the image quality, to develop the tooling necessary to fabricate lenticular lens array extrusion cylinders, and to develop enhanced fabrication technology for the extrusion cylinder. It was determined that the most viable cross-sectional shape for the lenticular lenses is elliptical. This shape dramatically improves the image quality. The relationship between the lens radius, conic constant, material refractive index, and thickness will be discussed. A significant challenge was to fabricate a diamond-cutting tool having the proper elliptical shape. Both true elliptical and pseudo-elliptical diamond tools were designed and fabricated. The plastic sheets extruded can be quite thin (< 0.25 mm) and, consequently, can be wrapped around cans and the like. Fabrication of the lenticular engraved extrusion cylinder required remarkable development considering the large physical size and weight of the cylinder, and the tight mechanical tolerances associated with the lenticular lens molds cut into the cylinder's surface. The development of the cutting tool and the lenticular engraved extrusion cylinder will be presented in addition to an illustrative comparison of current lenticular technology and the new technology. Three U.S. patents have been issued as a consequence of this research effort.
DNA Array-Based Gene Profiling
Mocellin, Simone; Provenzano, Maurizio; Rossi, Carlo Riccardo; Pilati, Pierluigi; Nitti, Donato; Lise, Mario
2005-01-01
Cancer is a heterogeneous disease in most respects, including its cellularity, different genetic alterations, and diverse clinical behaviors. Traditional molecular analyses are reductionist, assessing only 1 or a few genes at a time, thus working with a biologic model too specific and limited to confront a process whose clinical outcome is likely to be governed by the combined influence of many genes. The potential of functional genomics is enormous, because for each experiment, thousands of relevant observations can be made simultaneously. Accordingly, DNA array, like other high-throughput technologies, might catalyze and ultimately accelerate the development of knowledge in tumor cell biology. Although in its infancy, the implementation of DNA array technology in cancer research has already provided investigators with novel data and intriguing new hypotheses on the molecular cascade leading to carcinogenesis, tumor aggressiveness, and sensitivity to antiblastic agents. Given the revolutionary implications that the use of this technology might have in the clinical management of patients with cancer, principles of DNA array-based tumor gene profiling need to be clearly understood for the data to be correctly interpreted and appreciated. In the present work, we discuss the technical features characterizing this powerful laboratory tool and review the applications so far described in the field of oncology. PMID:15621987
Dobbs, M A; Lueker, M; Aird, K A; Bender, A N; Benson, B A; Bleem, L E; Carlstrom, J E; Chang, C L; Cho, H-M; Clarke, J; Crawford, T M; Crites, A T; Flanigan, D I; de Haan, T; George, E M; Halverson, N W; Holzapfel, W L; Hrubes, J D; Johnson, B R; Joseph, J; Keisler, R; Kennedy, J; Kermish, Z; Lanting, T M; Lee, A T; Leitch, E M; Luong-Van, D; McMahon, J J; Mehl, J; Meyer, S S; Montroy, T E; Padin, S; Plagge, T; Pryke, C; Richards, P L; Ruhl, J E; Schaffer, K K; Schwan, D; Shirokoff, E; Spieler, H G; Staniszewski, Z; Stark, A A; Vanderlinde, K; Vieira, J D; Vu, C; Westbrook, B; Williamson, R
2012-07-01
A technological milestone for experiments employing transition edge sensor bolometers operating at sub-Kelvin temperature is the deployment of detector arrays with 100s-1000s of bolometers. One key technology for such arrays is readout multiplexing: the ability to read out many sensors simultaneously on the same set of wires. This paper describes a frequency-domain multiplexed readout system which has been developed for and deployed on the APEX-SZ and South Pole Telescope millimeter wavelength receivers. In this system, the detector array is divided into modules of seven detectors, and each bolometer within the module is biased with a unique ∼MHz sinusoidal carrier such that the individual bolometer signals are well separated in frequency space. The currents from all bolometers in a module are summed together and pre-amplified with superconducting quantum interference devices operating at 4 K. Room temperature electronics demodulate the carriers to recover the bolometer signals, which are digitized separately and stored to disk. This readout system contributes little noise relative to the detectors themselves, is remarkably insensitive to unwanted microphonic excitations, and provides a technology pathway to multiplexing larger numbers of sensors.
The Sequencing Bead Array (SBA), a Next-Generation Digital Suspension Array
Akhras, Michael S.; Pettersson, Erik; Diamond, Lisa; Unemo, Magnus; Okamoto, Jennifer; Davis, Ronald W.; Pourmand, Nader
2013-01-01
Here we describe the novel Sequencing Bead Array (SBA), a complete assay for molecular diagnostics and typing applications. SBA is a digital suspension array using Next-Generation Sequencing (NGS), to replace conventional optical readout platforms. The technology allows for reducing the number of instruments required in a laboratory setting, where the same NGS instrument could be employed from whole-genome and targeted sequencing to SBA broad-range biomarker detection and genotyping. As proof-of-concept, a model assay was designed that could distinguish ten Human Papillomavirus (HPV) genotypes associated with cervical cancer progression. SBA was used to genotype 20 cervical tumor samples and, when compared with amplicon pyrosequencing, was able to detect two additional co-infections due to increased sensitivity. We also introduce in-house software Sphix, enabling easy accessibility and interpretation of results. The technology offers a multi-parallel, rapid, robust, and scalable system that is readily adaptable for a multitude of microarray diagnostic and typing applications, e.g. genetic signatures, single nucleotide polymorphisms (SNPs), structural variations, and immunoassays. SBA has the potential to dramatically change the way we perform probe-based applications, and allow for a smooth transition towards the technology offered by genomic sequencing. PMID:24116138
IRIS Arrays: Observing Wavefields at Multiple Scales and Frequencies
NASA Astrophysics Data System (ADS)
Sumy, D. F.; Woodward, R.; Frassetto, A.
2014-12-01
The Incorporated Research Institutions for Seismology (IRIS) provides instruments for creating and operating seismic arrays at a wide range of scales. As an example, for over thirty years the IRIS PASSCAL program has provided instruments to individual Principal Investigators to deploy arrays of all shapes and sizes on every continent. These arrays have ranged from just a few sensors to hundreds or even thousands of sensors, covering areas with dimensions of meters to thousands of kilometers. IRIS also operates arrays directly, such as the USArray Transportable Array (TA) as part of the EarthScope program. Since 2004, the TA has rolled across North America, at any given time spanning a swath of approximately 800 km by 2,500 km, and thus far sampling 2% of the Earth's surface. This achievement includes all of the lower-48 U.S., southernmost Canada, and now parts of Alaska. IRIS has also facilitated specialized arrays in polar environments and on the seafloor. In all cases, the data from these arrays are freely available to the scientific community. As the community of scientists who use IRIS facilities and data look to the future they have identified a clear need for new array capabilities. In particular, as part of its Wavefields Initiative, IRIS is exploring new technologies that can enable large, dense array deployments to record unaliased wavefields at a wide range of frequencies. Large-scale arrays might utilize multiple sensor technologies to best achieve observing objectives and optimize equipment and logistical costs. Improvements in packaging and power systems can provide equipment with reduced size, weight, and power that will reduce logistical constraints for large experiments, and can make a critical difference for deployments in harsh environments or other situations where rapid deployment is required. We will review the range of existing IRIS array capabilities with an overview of previous and current deployments and examples of data and results. We will review existing IRIS projects that explore new array capabilities and highlight future directions for IRIS instrumentation facilities.
Cell Engineering and Molecular Pharming for Biopharmaceuticals
Abdullah, M.A; Rahmah, Anisa ur; Sinskey, A.J; Rha, C.K
2008-01-01
Biopharmaceuticals are often produced by recombinant E. coli or mammalian cell lines. This is usually achieved by the introduction of a gene or cDNA coding for the protein of interest into a well-characterized strain of producer cells. Naturally, each recombinant production system has its own unique advantages and disadvantages. This paper examines the current practices, developments, and future trends in the production of biopharmaceuticals. Platform technologies for rapid screening and analyses of biosystems are reviewed. Strategies to improve productivity via metabolic and integrated engineering are also highlighted. PMID:19662143
NASA Astrophysics Data System (ADS)
Nikzad, Shouleh; Jewell, April D.; Hoenk, Michael E.; Jones, Todd J.; Hennessy, John; Goodsall, Tim; Carver, Alexander G.; Shapiro, Charles; Cheng, Samuel R.; Hamden, Erika T.; Kyne, Gillian; Martin, D. Christopher; Schiminovich, David; Scowen, Paul; France, Kevin; McCandliss, Stephan; Lupu, Roxana E.
2017-07-01
Exciting concepts are under development for flagship, probe class, explorer class, and suborbital class NASA missions in the ultraviolet/optical spectral range. These missions will depend on high-performance silicon detector arrays being delivered affordably and in high numbers. To that end, we have advanced delta-doping technology to high-throughput and high-yield wafer-scale processing, encompassing a multitude of state-of-the-art silicon-based detector formats and designs. We have embarked on a number of field observations, instrument integrations, and independent evaluations of delta-doped arrays. We present recent data and innovations from JPL's Advanced Detectors and Systems Program, including two-dimensional doping technology, JPL's end-to-end postfabrication processing of high-performance UV/optical/NIR arrays and advanced coatings for detectors. While this paper is primarily intended to provide an overview of past work, developments are identified and discussed throughout. Additionally, we present examples of past, in-progress, and planned observations and deployments of delta-doped arrays.
A Compact Low-Power Driver Array for VCSELs in 65-nm CMOS Technology
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zeng, Zhiyao; Sun, Kexu; Wang, Guanhua
This article presents a compact low-power 4 x 10 Gb/s quad-driver module for Vertical-Cavity Surface-Emitting Laser (VCSEL) arrays in a 65 nm CMOS technology. The side-by-side drivers can be directly wire bonded to the VCSEL diode array, supporting up to 4 channels. To increase the bandwidth of the driver, an internal feed-forward path is added for pole-zero cancellation, without increasing the power consumption. An edge-configurable pre-emphasis technique is proposed to achieve high bandwidth and minimize the asymmetry of the fall and rise times of the driver output current. Measurement results demonstrate a RMS jitter of 0.68 ps for 10 Gb/smore » operation. Tests demonstrate negligible crosstalk between channels. Under irradiation, the modulation amplitude degrades less than 5% up to 300 Mrad ionizing dose. Finally, the area of the quaddriver array is 500 μm by 1000 μm and the total power consumption for the entire driver array chip is 130 mW for the typical current setting.« less
NASA Astrophysics Data System (ADS)
Lv, Zhibin; Yu, Jiefeng; Wu, Hongwei; Shang, Jian; Wang, Dan; Hou, Shaocong; Fu, Yongping; Wu, Kai; Zou, Dechun
2012-02-01
A type of highly efficient completely flexible fiber-shaped solar cell based on TiO2 nanotube array is successfully prepared. Under air mass 1.5G (100 mW cm-2) illumination conditions, the photoelectric conversion efficiency of the solar cell approaches 7%, the highest among all fiber-shaped cells based on TiO2 nanotube arrays and the first completely flexible fiber-shaped DSSC. The fiber-shaped solar cell demonstrates good flexibility, which makes it suitable for modularization using weaving technologies.A type of highly efficient completely flexible fiber-shaped solar cell based on TiO2 nanotube array is successfully prepared. Under air mass 1.5G (100 mW cm-2) illumination conditions, the photoelectric conversion efficiency of the solar cell approaches 7%, the highest among all fiber-shaped cells based on TiO2 nanotube arrays and the first completely flexible fiber-shaped DSSC. The fiber-shaped solar cell demonstrates good flexibility, which makes it suitable for modularization using weaving technologies. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr11532h
64-element photodiode array for scintillation detection of x-rays
NASA Astrophysics Data System (ADS)
Wegrzecki, Maciej; Wolski, Dariusz; Bar, Jan; Budzyński, Tadeusz; Chłopik, Arkadiusz; Grabiec, Piotr; Kłos, Helena; Panas, Andrzej; Piotrowski, Tadeusz; Słysz, Wojciech; Stolarski, Maciej; Szmigiel, Dariusz; Wegrzecka, Iwona; Zaborowski, Michał
2014-08-01
The paper presents the design, technology and parameters of a new, silicon 64-element linear photodiode array developed at the Institute of Electron Technology (ITE) for the detection of scintillations emitted by CsI scintillators (λ≈550 nm). The arrays are used in a device for examining the content of containers at border crossings under development at the National Centre for Nuclear Research. Two arrays connected with a scintillator block (128 CsI scintillators) form a 128-channel detection module. The array consists of 64 epiplanar photodiode structures (5.1 × 7.2 mm) and a 5.3 mm module. p+-ν-n+ photodiode structures are optimised for the detection of radiation of λ≈ 550 nm wavelength with no voltage applied (photovoltaic mode). The structures are mounted on an epoxy-glass laminate substrate, copper-clad on both sides, on which connections with a common anode and separate cathode leads are located. The photosensitive surface of photodiodes is covered with a special silicone gel, which protects photodiodes against the mechanical impact of scintillators
Solar Arrays for Low-Irradiance Low-Temperature and High-Radiation Environments
NASA Technical Reports Server (NTRS)
Boca, Andreea (Principal Investigator); Stella, Paul; Kerestes, Christopher; Sharps, Paul
2017-01-01
This is the Base Period final report DRAFT for the JPL task 'Solar Arrays for Low-Irradiance Low-Temperature and High-Radiation Environments', under Task Plan 77-16518 TA # 21, for NASA's Extreme Environments Solar Power (EESP) project. This report covers the Base period of performance, 7/18/2016 through 5/2/2017.The goal of this project is to develop an ultra-high efficiency lightweight scalable solar array technology for low irradiance, low temperature and high-radiation (LILT/Rad) environments. The benefit this technology will bring to flight systems is a greater than 20 reduction in solar array surface area, and a six-fold reduction in solar array mass and volume. The EESP project objectives are summarized in the 'NRA Goal' column of Table 1. Throughout this report, low irradiance low temperature (LILT) refers to 5AU -125 C test conditions; beginning of life (BOL) refers to the cell state prior to radiation exposure; and end of life (EOL) refers to the test article condition after exposure to a radiation dose of 4e15 1MeV e(-)/cm(exp 2).
A Compact Low-Power Driver Array for VCSELs in 65-nm CMOS Technology
Zeng, Zhiyao; Sun, Kexu; Wang, Guanhua; ...
2017-05-08
This article presents a compact low-power 4 x 10 Gb/s quad-driver module for Vertical-Cavity Surface-Emitting Laser (VCSEL) arrays in a 65 nm CMOS technology. The side-by-side drivers can be directly wire bonded to the VCSEL diode array, supporting up to 4 channels. To increase the bandwidth of the driver, an internal feed-forward path is added for pole-zero cancellation, without increasing the power consumption. An edge-configurable pre-emphasis technique is proposed to achieve high bandwidth and minimize the asymmetry of the fall and rise times of the driver output current. Measurement results demonstrate a RMS jitter of 0.68 ps for 10 Gb/smore » operation. Tests demonstrate negligible crosstalk between channels. Under irradiation, the modulation amplitude degrades less than 5% up to 300 Mrad ionizing dose. Finally, the area of the quaddriver array is 500 μm by 1000 μm and the total power consumption for the entire driver array chip is 130 mW for the typical current setting.« less
Assessment of SEPS solar array technology for orbital service module application
NASA Technical Reports Server (NTRS)
1978-01-01
Work performed in the following assessment areas on the SEPS solar array is reported: (1) requirements definition, (2) electrical design evaluation, (3) mechanical design evaluation, and (4) design modification analysis. General overall assessment conclusions are summarized. There are no known serious design limitations involved in the implementation of the recommended design modifications. A section of orbiter and array engineering drawings is included.
Preliminary Assessment of Microwave Readout Multiplexing Factor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Croce, Mark Philip; Koehler, Katrina Elizabeth; Rabin, Michael W.
2017-01-23
Ultra-high resolution microcalorimeter gamma spectroscopy is a new non-destructive assay technology for measurement of plutonium isotopic composition, with the potential to reduce total measurement uncertainty to a level competitive with destructive analysis methods [1-4]. Achieving this level of performance in practical applications requires not only the energy resolution now routinely achieved with transition-edge sensor microcalorimeter arrays (an order of magnitude better than for germanium detectors) but also high throughput. Microcalorimeter gamma spectrometers have not yet achieved detection efficiency and count rate capability that is comparable to germanium detectors, largely because of limits from existing readout technology. Microcalorimeter detectors must bemore » operated at low temperature to achieve their exceptional energy resolution. Although the typical 100 mK operating temperatures can be achieved with reliable, cryogen-free systems, the cryogenic complexity and heat load from individual readout channels for large sensor arrays is prohibitive. Multiplexing is required for practical systems. The most mature multiplexing technology at present is time-division multiplexing (TDM) [3, 5-6]. In TDM, the sensor outputs are switched by applying bias current to one SQUID amplifier at a time. Transition-edge sensor (TES) microcalorimeter arrays as large as 256 pixels have been developed for X-ray and gamma-ray spectroscopy using TDM technology. Due to bandwidth limits and noise scaling, TDM is limited to a maximum multiplexing factor of approximately 32-40 sensors on one readout line [8]. Increasing the size of microcalorimeter arrays above the kilopixel scale, required to match the throughput of germanium detectors, requires the development of a new readout technology with a much higher multiplexing factor.« less
NASA Technical Reports Server (NTRS)
Miller, James G.
1994-01-01
In this Progress Report, we describe our continuing research activities concerning the development and implementation of advanced ultrasonic nondestructive evaluation methods applied to the inspection and characterization of complex composite structures. We explore the feasibility of implementing medical linear array imaging technology as a viable ultrasonic-based nondestructive evaluation method to inspect and characterize complex materials. As an initial step toward the application of linear array imaging technology to the interrogation of a wide range of complex composite structures, we present images obtained using an unmodified medical ultrasonic imaging system of two epoxy-bonded aluminum plate specimens, each with intentionally disbonded regions. These images are compared with corresponding conventional ultrasonic contact transducer measurements in order to assess whether these images can detect disbonded regions and provide information regarding the nature of the disbonded region. We present a description of a standoff/delay fixture which has been designed, constructed, and implemented on a Hewlett-Packard SONOS 1500 medical imaging system. This standoff/delay fixture, when attached to a 7.5 MHz linear array probe, greatly enhances our ability to interrogate flat plate specimens. The final section of this Progress Report describes a woven composite plate specimen that has been specially machined to include intentional flaws. This woven composite specimen will allow us to assess the feasibility of applying linear array imaging technology to the inspection and characterization of complex textile composite materials. We anticipate the results of this on-going investigation may provide a step toward the development of a rapid, real-time, and portable method of ultrasonic inspection and characterization based on linear array technology.
Murayama, Kodai; Genkawa, Takuma; Ishikawa, Daitaro; Komiyama, Makoto; Ozaki, Yukihiro
2013-02-01
In the fine chemicals industry, particularly in the pharmaceutical industry, advanced sensing technologies have recently begun being incorporated into the process line in order to improve safety and quality in accordance with process analytical technology. For estimating the quality of powders without preparation during drug formulation, near-infrared (NIR) spectroscopy has been considered the most promising sensing approach. In this study, we have developed a compact polychromator-type NIR spectrometer equipped with a photodiode (PD) array detector. This detector is consisting of 640 InGaAs-PD elements with 20-μm pitch. Some high-specification spectrometers, which use InGaAs-PD with 512 elements, have a wavelength resolution of about 1.56 nm when covering 900-1700 nm range. On the other hand, the newly developed detector, having the PD with one of the world's highest density, enables wavelength resolution of below 1.25 nm. Moreover, thanks to the combination with a highly integrated charge amplifier array circuit, measurement speed of the detector is higher by two orders than that of existing PD array detectors. The developed spectrometer is small (120 mm × 220 mm × 200 mm) and light (6 kg), and it contains various key devices including the high-density and high-sensitivity PD array detector, NIR technology, and spectroscopy technology for a spectroscopic analyzer that has the required detection mechanism and high sensitivity for powder measurement, as well as a high-speed measuring function for blenders. Moreover, we have evaluated the characteristics of the developed NIR spectrometer, and the measurement of powder samples confirmed that it has high functionality.
Subtraction of cap-trapped full-length cDNA libraries to select rare transcripts.
Hirozane-Kishikawa, Tomoko; Shiraki, Toshiyuki; Waki, Kazunori; Nakamura, Mari; Arakawa, Takahiro; Kawai, Jun; Fagiolini, Michela; Hensch, Takao K; Hayashizaki, Yoshihide; Carninci, Piero
2003-09-01
The normalization and subtraction of highly expressed cDNAs from relatively large tissues before cloning dramatically enhanced the gene discovery by sequencing for the mouse full-length cDNA encyclopedia, but these methods have not been suitable for limited RNA materials. To normalize and subtract full-length cDNA libraries derived from limited quantities of total RNA, here we report a method to subtract plasmid libraries excised from size-unbiased amplified lambda phage cDNA libraries that avoids heavily biasing steps such as PCR and plasmid library amplification. The proportion of full-length cDNAs and the gene discovery rate are high, and library diversity can be validated by in silico randomization.
Energy requirement for the production of silicon solar arrays
NASA Technical Reports Server (NTRS)
Lindmayer, J.; Wihl, M.; Scheinine, A.; Rosenfield, T.; Wrigley, C. Y.; Morrison, A.; Anderson, J.; Clifford, A.; Lafky, W.
1977-01-01
The results of a study to investigate the feasibility of manufacturing photovoltaic solar array modules by the use of energy obtained from similar or identical photovoltaic sources are presented. The primary objective of this investigation was the characterization of the energy requirements of current and developing technologies which comprise the photovoltaic field. For cross-checking the energies of prevailing technologies data were also used and the wide-range assessment of alternative technologies included different refinement methods, various ways of producing light sheets, semicrystalline cells, etc. Energy data are utilized to model the behavior of a future solar breeder plant under various operational conditions.
NASA Astrophysics Data System (ADS)
Arnold, Michael
Calculations have indicated that aligned arrays of semiconducting carbon nanotubes (CNTs) promise to outperform conventional semiconducting materials in short-channel, aggressively scaled field effect transistors (FETs) like those used in semiconductor logic and high frequency amplifier technologies. These calculations have been based on extrapolation of measurements of FETs based on one CNT, in which ballistic transport approaching the quantum conductance limit of 2Go = 4e2/h has been achieved. However, constraints in CNT sorting, processing, alignment, and contacts give rise to non-idealities when CNTs are implemented in densely-packed parallel arrays, which has resulted in a conductance per CNT far from 2Go. The consequence has been that it has been very difficult to create high performance CNT array FETs, and CNT array FETs have not outperformed but rather underperformed channel materials such as Si by 6 x or more. Here, we report nearly ballistic CNT array FETs at a density of 50 CNTs um-1, created via CNT sorting, wafer-scale alignment and assembly, and treatment. The on-state conductance in the arrays is as high as 0.46 Go per CNT, and the conductance of the arrays reaches 1.7 mS um-1, which is 7 x higher than previous state-of-the-art CNT array FETs made by other methods. The saturated on-state current density reaches 900 uA um-1 and is similar to or exceeds that of Si FETs when compared at equivalent gate oxide thickness, off-state current density, and channel length. The on-state current density exceeds that of GaAs FETs, as well. This leap in CNT FET array performance is a significant advance towards the exploitation of CNTs in high-performance semiconductor electronics technologies.
Next generation miniature simultaneous multi-hyperspectral imaging systems
NASA Astrophysics Data System (ADS)
Hinnrichs, Michele; Gupta, Neelam
2014-03-01
The concept for a hyperspectral imaging system using a Fabry-Perot tunable filter (FPTF) array that is fabricated using "miniature optical electrical mechanical system" (MOEMS) technology. [1] Using an array of FPTF as an approach to hyperspectral imaging relaxes wavelength tuning requirements considerably because of the reduced portion of the spectrum that is covered by each element in the array. In this paper, Pacific Advanced Technology and ARL present the results of a concept design and performed analysis of a MOEMS based tunable Fabry-Perot array (FPTF) to perform simultaneous multispectral and hyperspectral imaging with relatively high spatial resolution. The concept design was developed with support of an Army SBIR Phase I program The Fabry-Perot tunable MOEMS filter array was combined with a miniature optics array and a focal plane array of 1024 x 1024 pixels to produce 16 colors every frame of the camera. Each color image has a spatial resolution of 256 x 256 pixels with an IFOV of 1.7 mrads and FOV of 25 degrees. The spectral images are collected simultaneously allowing high resolution spectral-spatial-temporal information in each frame of the camera, thus enabling the implementation of spectral-temporal-spatial algorithms in real-time to provide high sensitivity for the detection of weak signals in a high clutter background environment with low sensitivity to camera motion. The challenge in the design was the independent actuation of each Fabry Perot element in the array allowing for individual tuning. An additional challenge was the need to maximize the fill factor to improve the spatial coverage with minimal dead space. This paper will only address the concept design and analysis of the Fabry-Perot tunable filter array. A previous paper presented at SPIE DSS in 2012 explained the design of the optical array.
Low cost silicon solar cell array
NASA Technical Reports Server (NTRS)
Bartels, F. T. C.
1974-01-01
The technological options available for producing low cost silicon solar cell arrays were examined. A project value of approximately $250/sq m and $2/watt is projected, based on mass production capacity demand. Recommendations are included for the most promising cost reduction options.
Solar Power for Future NASA Missions
NASA Technical Reports Server (NTRS)
Bailey, Sheila G.; Landis, Geoffrey A.
2014-01-01
An overview of NASA missions and technology development efforts are discussed. Future spacecraft will need higher power, higher voltage, and much lower cost solar arrays to enable a variety of missions. One application driving development of these future arrays is solar electric propulsion.
Cloning and sequence analysis of Hemonchus contortus HC58cDNA.
Muleke, Charles I; Ruofeng, Yan; Lixin, Xu; Xinwen, Bo; Xiangrui, Li
2007-06-01
The complete coding sequence of Hemonchus contortus HC58cDNA was generated by rapid amplification of cDNA ends and polymerase chain reaction using primers based on the 5' and 3' ends of the parasite mRNA, accession no. AF305964. The HC58cDNA gene was 851 bp long, with open reading frame of 717 bp, precursors to 239 amino acids coding for approximately 27 kDa protein. Analysis of amino acid sequence revealed conserved residues of cysteine, histidine, asparagine, occluding loop pattern, hemoglobinase motif and glutamine of the oxyanion hole characteristic of cathepsin B like proteases (CBL). Comparison of the predicted amino acid sequences showed the protein shared 33.5-58.7% identity to cathepsin B homologues in the papain clan CA family (family C1). Phylogenetic analysis revealed close evolutionary proximity of the protein sequence to counterpart sequences in the CBL, suggesting that HC58cDNA was a member of the papain family.
One GigaSample Per Second Data Acquisition using Available Gate Array Technology
NASA Technical Reports Server (NTRS)
Wagner, K.W.
1999-01-01
A new National Aeronautics and Space Administration instrument forced demanding requirements upon its altimeter digitizer system. Eight-bit data would be generated at a rate of one billion samples per second. NASA had never before attempted to capture such high-speed data in the radiation, low-power, no-convective-cooling, limited-board-area environment of space. This presentation describes how the gate array technology available at the time of the design was used to implement this one gigasample per second data acquisition system
NASA Astrophysics Data System (ADS)
Liu, Gang; Wen, Desheng; Song, Zongxi
2017-10-01
With the development of aeronautics and astronautics, higher resolution requirement of the telescope was necessary. However, the increase in resolution of conventional telescope required larger apertures, whose size, weight and power consumption could be prohibitively expensive. This limited the further development of the telescope. This paper introduced a new imaging technology using interference—Compact Passive Interference Imaging Technology with High Resolution, and proposed a rearranging method for the arrangement of the lenslet array to obtain continuously object spatial frequency.
Lightweight solar array blanket tooling, laser welding and cover process technology
NASA Technical Reports Server (NTRS)
Dillard, P. A.
1983-01-01
A two phase technology investigation was performed to demonstrate effective methods for integrating 50 micrometer thin solar cells into ultralightweight module designs. During the first phase, innovative tooling was developed which allows lightweight blankets to be fabricated in a manufacturing environment with acceptable yields. During the second phase, the tooling was improved and the feasibility of laser processing of lightweight arrays was confirmed. The development of the cell/interconnect registration tool and interconnect bonding by laser welding is described.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Joyner, Dominique; Fortney, Julian; Chakraborty, Romy
2010-05-17
The Biolog OmniLog? Phenotype MicroArray (PM) plate technology was successfully adapted to generate a select phenotypic profile of the strict anaerobe Geobacter metallireducens (G.m.). The profile generated for G.m. provides insight into the chemical sensitivity of the organism as well as some of its metabolic capabilities when grown with a basal medium containing acetate and Fe(III). The PM technology was developed for aerobic organisms. The reduction of a tetrazolium dye by the test organism represents metabolic activity on the array which is detected and measured by the OmniLog(R) system. We have previously adapted the technology for the anaerobic sulfate reducingmore » bacterium Desulfovibrio vulgaris. In this work, we have taken the technology a step further by adapting it for the iron reducing obligate anaerobe Geobacter metallireducens. In an osmotic stress microarray it was determined that the organism has higher sensitivity to impermeable solutes 3-6percent KCl and 2-5percent NaNO3 that result in osmotic stress by osmosis to the cell than to permeable non-ionic solutes represented by 5-20percent ethylene glycol and 2-3percent urea. The osmotic stress microarray also includes an array of osmoprotectants and precursor molecules that were screened to identify substrates that would provide osmotic protection to NaCl stress. None of the substrates tested conferred resistance to elevated concentrations of salt. Verification studies in which G.m. was grown in defined medium amended with 100mM NaCl (MIC) and the common osmoprotectants betaine, glycine and proline supported the PM findings. Further verification was done by analysis of transcriptomic profiles of G.m. grown under 100mM NaCl stress that revealed up-regulation of genes related to degradation rather than accumulation of the above-mentioned osmoprotectants. The phenotypic profile, supported by additional analysis indicates that the accumulation of these osmoprotectants as a response to salt stress does not occur in G.m. and response to stress must occur by other mechanisms. The Phenotype MicroArray technology can be reliably used as a rapid screening tool for characterization in anaerobic microbial ecology.« less
Rode, Tone Mari; Berget, Ingunn; Langsrud, Solveig; Møretrø, Trond; Holck, Askild
2009-07-01
Microorganisms are constantly exposed to new and altered growth conditions, and respond by changing gene expression patterns. Several methods for studying gene expression exist. During the last decade, the analysis of microarrays has been one of the most common approaches applied for large scale gene expression studies. A relatively new method for gene expression analysis is MassARRAY, which combines real competitive-PCR and MALDI-TOF (matrix-assisted laser desorption/ionization time-of-flight) mass spectrometry. In contrast to microarray methods, MassARRAY technology is suitable for analysing a larger number of samples, though for a smaller set of genes. In this study we compare the results from MassARRAY with microarrays on gene expression responses of Staphylococcus aureus exposed to acid stress at pH 4.5. RNA isolated from the same stress experiments was analysed using both the MassARRAY and the microarray methods. The MassARRAY and microarray methods showed good correlation. Both MassARRAY and microarray estimated somewhat lower fold changes compared with quantitative real-time PCR (qRT-PCR). The results confirmed the up-regulation of the urease genes in acidic environments, and also indicated the importance of metal ion regulation. This study shows that the MassARRAY technology is suitable for gene expression analysis in prokaryotes, and has advantages when a set of genes is being analysed for an organism exposed to many different environmental conditions.
Lectin cDNA and transgenic plants derived therefrom
Raikhel, N.V.
1994-01-04
Transgenic plants containing cDNA encoding Gramineae lectin are described. The plants preferably contain cDNA coding for barley lectin and store the lectin in the leaves. The transgenic plants, particularly the leaves exhibit insecticidal and fungicidal properties. GOVERNMENT RIGHTS This application was funded under Department of Energy Contract DE-AC02-76ER01338. The U.S. Government has certain rights under this application and any patent issuing thereon. .
Lectin cDNA and transgenic plants derived therefrom
Raikhel, Natasha V.
1994-01-04
Transgenic plants containing cDNA encoding Gramineae lectin are described. The plants preferably contain cDNA coding for barley lectin and store the lectin in the leaves. The transgenic plants, particularly the leaves exhibit insecticidal and fungicidal properties. GOVERNMENT RIGHTS This application was funded under Department of Energy Contract DE-AC02-76ER01338. The U.S. Government has certain rights under this application and any patent issuing thereon.
cDNA library construction of two human Demodexspecies.
Niu, DongLing; Wang, RuiLing; Zhao, YaE; Yang, Rui; Hu, Li; Lei, YuYang; Dan, WeiChao
2017-06-01
The research of Demodex, a type of pathogen causing various dermatoses in animals and human beings, is lacking at RNA level. This study aims at extracting RNA and constructing cDNA library for Demodex. First, P. cuniculiand D. farinaewere mixed to establish homogenization method for RNA extraction. Second, D. folliculorumand D. breviswere collected and preserved in Trizol, which were mixed with D. farinaerespectively to extract RNA. Finally, cDNA library was constructed and its quality was assessed. The results indicated that for D. folliculorum& D. farinae, the recombination rate of cDNA library was 90.67% and the library titer was 7.50 × 104 pfu/ml. 17 of the 59 positive clones were predicted to be of D. folliculorum; For D. brevis& D. farinae, the recombination rate was 90.96% and the library titer was 7.85 x104 pfu/ml. 40 of the 59 positive clones were predicted to be of D. brevis. Further detection by specific primers demonstrated that mtDNA cox1, cox3and ATP6 detected from cDNA libraries had 96.52%-99.73% identities with the corresponding sequences in GenBank. In conclusion, the cDNA libraries constructed for Demodexmixed with D. farinaewere successful and could satisfy the requirements for functional genes detection.
Hurrelbrink, R J; Nestorowicz, A; McMinn, P C
1999-12-01
An infectious cDNA clone of Murray Valley encephalitis virus prototype strain 1-51 (MVE-1-51) was constructed by stably inserting genome-length cDNA into the low-copy-number plasmid vector pMC18. Designated pMVE-1-51, the clone consisted of genome-length cDNA of MVE-1-51 under the control of a T7 RNA polymerase promoter. The clone was constructed by using existing components of a cDNA library, in addition to cDNA of the 3' terminus derived by RT-PCR of poly(A)-tailed viral RNA. Upon comparison with other flavivirus sequences, the previously undetermined sequence of the 3' UTR was found to contain elements conserved throughout the genus FLAVIVIRUS: RNA transcribed from pMVE-1-51 and subsequently transfected into BHK-21 cells generated infectious virus. The plaque morphology, replication kinetics and antigenic profile of clone-derived virus (CDV-1-51) was similar to the parental virus in vitro. Furthermore, the virulence properties of CDV-1-51 and MVE-1-51 (LD(50) values and mortality profiles) were found to be identical in vivo in the mouse model. Through site-directed mutagenesis, the infectious clone should serve as a valuable tool for investigating the molecular determinants of virulence in MVE virus.
Isolation of a cDNA Encoding a Granule-Bound 152-Kilodalton Starch-Branching Enzyme in Wheat1
Båga, Monica; Nair, Ramesh B.; Repellin, Anne; Scoles, Graham J.; Chibbar, Ravindra N.
2000-01-01
Screening of a wheat (Triticum aestivum) cDNA library for starch-branching enzyme I (SBEI) genes combined with 5′-rapid amplification of cDNA ends resulted in isolation of a 4,563-bp composite cDNA, Sbe1c. Based on sequence alignment to characterized SBEI cDNA clones isolated from plants, the SBEIc predicted from the cDNA sequence was produced with a transit peptide directing the polypeptide into plastids. Furthermore, the predicted mature form of SBEIc was much larger (152 kD) than previously characterized plant SBEI (80–100 kD) and contained a partial duplication of SBEI sequences. The first SBEI domain showed high amino acid similarity to a 74-kD wheat SBEI-like protein that is inactive as a branching enzyme when expressed in Escherichia coli. The second SBEI domain on SBEIc was identical in sequence to a functional 87-kD SBEI produced in the wheat endosperm. Immunoblot analysis of proteins produced in developing wheat kernels demonstrated that the 152-kD SBEIc was, in contrast to the 87- to 88-kD SBEI, preferentially associated with the starch granules. Proteins similar in size and recognized by wheat SBEI antibodies were also present in Triticum monococcum, Triticum tauschii, and Triticum turgidum subsp. durum. PMID:10982440
A meta-data based method for DNA microarray imputation.
Jörnsten, Rebecka; Ouyang, Ming; Wang, Hui-Yu
2007-03-29
DNA microarray experiments are conducted in logical sets, such as time course profiling after a treatment is applied to the samples, or comparisons of the samples under two or more conditions. Due to cost and design constraints of spotted cDNA microarray experiments, each logical set commonly includes only a small number of replicates per condition. Despite the vast improvement of the microarray technology in recent years, missing values are prevalent. Intuitively, imputation of missing values is best done using many replicates within the same logical set. In practice, there are few replicates and thus reliable imputation within logical sets is difficult. However, it is in the case of few replicates that the presence of missing values, and how they are imputed, can have the most profound impact on the outcome of downstream analyses (e.g. significance analysis and clustering). This study explores the feasibility of imputation across logical sets, using the vast amount of publicly available microarray data to improve imputation reliability in the small sample size setting. We download all cDNA microarray data of Saccharomyces cerevisiae, Arabidopsis thaliana, and Caenorhabditis elegans from the Stanford Microarray Database. Through cross-validation and simulation, we find that, for all three species, our proposed imputation using data from public databases is far superior to imputation within a logical set, sometimes to an astonishing degree. Furthermore, the imputation root mean square error for significant genes is generally a lot less than that of non-significant ones. Since downstream analysis of significant genes, such as clustering and network analysis, can be very sensitive to small perturbations of estimated gene effects, it is highly recommended that researchers apply reliable data imputation prior to further analysis. Our method can also be applied to cDNA microarray experiments from other species, provided good reference data are available.
Vallée, Maud; Gravel, Catherine; Palin, Marie-France; Reghenas, Hélène; Stothard, Paul; Wishart, David S; Sirard, Marc-André
2005-07-01
The main objective of the present study was to identify novel oocyte-specific genes in three different species: bovine, mouse, and Xenopus laevis. To achieve this goal, two powerful technologies were combined: a polymerase chain reaction (PCR)-based cDNA subtraction, and cDNA microarrays. Three subtractive libraries consisting of 3456 clones were established and enriched for oocyte-specific transcripts. Sequencing analysis of the positive insert-containing clones resulted in the following classification: 53% of the clones corresponded to known cDNAs, 26% were classified as uncharacterized cDNAs, and a final 9% were classified as novel sequences. All these clones were used for cDNA microarray preparation. Results from these microarray analyses revealed that in addition to already known oocyte-specific genes, such as GDF9, BMP15, and ZP, known genes with unknown function in the oocyte were identified, such as a MLF1-interacting protein (MLF1IP), B-cell translocation gene 4 (BTG4), and phosphotyrosine-binding protein (xPTB). Furthermore, 15 novel oocyte-specific genes were validated by reverse transcription-PCR to confirm their preferential expression in the oocyte compared to somatic tissues. The results obtained in the present study confirmed that microarray analysis is a robust technique to identify true positives from the suppressive subtractive hybridization experiment. Furthermore, obtaining oocyte-specific genes from three species simultaneously allowed us to look at important genes that are conserved across species. Further characterization of these novel oocyte-specific genes will lead to a better understanding of the molecular mechanisms related to the unique functions found in the oocyte.
Goetz, Frederick W; Norberg, Birgitta; McCauley, Linda A R; Iliev, Dimitar B
2004-03-01
The full-length cDNA for the cod (Gadus morhua) StAR was cloned by RT-PCR and library screening using ovarian RNA. From the library screening, 2 size classes of cDNA were obtained; a 1577 bp cDNA (cStAR1) and a 2851 bp cDNA (cStAR2). The cStAR1 cDNA presumably encodes a protein of 286 amino acids. The cStAR2 cDNA was composed of 6 separated sequences that contained all of the coding regions of cStAR1 when added together, but also contained 5 noncoding regions not observed in cStAR1. Polymerase chain reactions of cod genomic DNA produced products slightly larger than cStAR2. The sequence of these products were the same as cStAR2 but revealed one additional noncoding region (intron). Thus, the fish StAR gene contains the same number of exons (7) and introns (6) as observed in mammals, but is approximately half the size of the mammalian gene. Using Northern analysis and RT-PCR, cStAR1 expression was observed only in testes, ovaries and head kidneys. Polymerase chain reaction products were also observed using cDNA from steroidogenic tissues and primers designed to regions specific for cStAR2, indicating that cStAR2 is expressed in tissues and may account for the presence of larger transcripts observed on Northern blots.
[Construction and characterization of a cDNA library from human liver tissue of cirrhosis].
Chen, Xiao-hong; Chen, Zhi; Chen, Feng; Zhu, Hai-hong; Zhou, Hong-juan; Yao, Hang-ping
2005-03-01
To construct a cDNA library from human liver tissue of cirrhosis. The total RNA from human liver tissue of cirrhosis was extracted using Trizol method, and the mRNA was purified using mRNA purification kit. SMART technique and CDSIII/3' primer were used for first-strand cDNA synthesis. Long distance PCR was then used to synthesize the double-strand cDNA that was then digested by proteinase K and Sfi I, and was fractionated by CHOMA SPIN-400 column. The cDNA fragments longer than 0.4 kb were collected and ligated to lambdaTripl Ex2 vector. Then lambda-phage packaging reaction and library amplification were performed. The qualities of both unamplified and amplified cDNA libraries was strictly checked by conventional titer determination. Eleven plaques were randomly picked and tested using PCR with universal primers derived from the sequence flanking the vector. The titers of unamplifed and amplified libraries were 1.03 x 10(6) pfu/ml and 1.36 x 10(9) pfu/ml respectively. The percentages of recombinants from both libraries were 97.24 % in unamplified library and 99.02 % in amplified library. The lengths of the inserts were 1.02 kb in average (36.36 % 1 approximately equals 2 kb and 63.64 % 0.5 approximately equals 1.0 kb). A high quality cDNA library from human liver tissue of cirrhosis was constructed successfully, which can be used for screening and cloning new special genes associated with the occurrence of cirrhosis.
cDNA cloning of rat and human medium chain acyl-CoA dehydrogenase (MCAD)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Matsubara, Y.; Kraus, J.P.; Rosenberg, L.E.
MCAD is one of three mitochondrial flavoenzymes which catalyze the first step in the ..beta..-oxidation of straight chain fatty acids. It is a tetramer with a subunit Mr of 45 kDa. MCAD is synthesized in the cytosol as a 49 kDa precursor polypeptide (pMCAD), imported into mitochondria, and cleaved to the mature form. Genetic deficiency of MCAD causes recurrent episodes of hypoglycemic coma accompanied by medium chain dicarboxylic aciduria. Employing a novel approach, the authors now report isolation of partial rat and human cDNA clones encoding pMCAD. mRNA encoding pMCAD was purified to near homogeneity by polysome immunoadsorption using polyclonalmore » monospecific antibody. Single-stranded (/sup 32/P)labeled cDNA probe was synthesized using the enriched mRNA as template, and was used to screen directly 16,000 colonies from a total rat liver cDNA library constructed in pBR322. One clone (600 bp) was detected by in situ hybridization. Hybrid-selected translation with this cDNA yielded a 49 kDa polypeptide indistinguishable in size from rat pMCAD and immunoprecipitable with anti-MCAD antibody. Using the rat cDNA as probe, 43,000 colonies from a human liver cDNA library were screened. Four identical positive clones (400 bp) were isolated and positively identified by hybrid-selected translation and immunoprecipitation. The sizes of rat and human mRNAs encoding pMCAD were 2.2 kb and 2.4 kb, respectively, as determined by Northern blotting.« less
Cost-effective sequencing of full-length cDNA clones powered by a de novo-reference hybrid assembly.
Kuroshu, Reginaldo M; Watanabe, Junichi; Sugano, Sumio; Morishita, Shinichi; Suzuki, Yutaka; Kasahara, Masahiro
2010-05-07
Sequencing full-length cDNA clones is important to determine gene structures including alternative splice forms, and provides valuable resources for experimental analyses to reveal the biological functions of coded proteins. However, previous approaches for sequencing cDNA clones were expensive or time-consuming, and therefore, a fast and efficient sequencing approach was demanded. We developed a program, MuSICA 2, that assembles millions of short (36-nucleotide) reads collected from a single flow cell lane of Illumina Genome Analyzer to shotgun-sequence approximately 800 human full-length cDNA clones. MuSICA 2 performs a hybrid assembly in which an external de novo assembler is run first and the result is then improved by reference alignment of shotgun reads. We compared the MuSICA 2 assembly with 200 pooled full-length cDNA clones finished independently by the conventional primer-walking using Sanger sequencers. The exon-intron structure of the coding sequence was correct for more than 95% of the clones with coding sequence annotation when we excluded cDNA clones insufficiently represented in the shotgun library due to PCR failure (42 out of 200 clones excluded), and the nucleotide-level accuracy of coding sequences of those correct clones was over 99.99%. We also applied MuSICA 2 to full-length cDNA clones from Toxoplasma gondii, to confirm that its ability was competent even for non-human species. The entire sequencing and shotgun assembly takes less than 1 week and the consumables cost only approximately US$3 per clone, demonstrating a significant advantage over previous approaches.
Cheng, Xiao-Rui; Zhou, Wen-Xia; Zhang, Yong-Xiang
2006-05-01
Alzheimer' s disease (AD) is the most common form of dementia in the elderly. AD is an invariably fatal neurodegenerative disorder with no effective treatment. Senescence-accelerated mouse prone 8 (SAMP8) is a model for studying age-related cognitive impairments and also is a good model to study brain aging and one of mouse model of AD. The technique of cDNA microarray can monitor the expression levels of thousands of genes simultaneously and can be used to study AD with the character of multi-mechanism, multi-targets and multi-pathway. In order to disclose the mechanism of AD and find the drug targets of AD, cDNA microarray containing 3136 cDNAs amplified from the suppression subtracted cDNA library of hippocampus of SAMP8 and SAMR1 was prepared with 16 blocks and 14 x 14 pins, the housekeeping gene beta-actin and G3PDH as inner conference. The background of this microarray was low and unanimous, and dots divided evenly. The conditions of hybridization and washing were optimized during the hybridization of probe and target molecule. After the data of hybridization analysis, the differential expressed cDNAs were sequenced and analyzed by the bioinformatics, and some of genes were quantified by the real time RT-PCR and the reliability of this cDNA microarray were validated. This cDNA microarray may be the good means to select the differential expressed genes and disclose the molecular mechanism of SAMP8's brain aging and AD.
Takamitsu, Emi; Otsuka, Motoaki; Haebara, Tatsuki; Yano, Manami; Matsuzaki, Kanako; Kobuchi, Hirotsugu; Moriya, Koko; Utsumi, Toshihiko
2015-01-01
To identify physiologically important human N-myristoylated proteins, 90 cDNA clones predicted to encode human N-myristoylated proteins were selected from a human cDNA resource (4,369 Kazusa ORFeome project human cDNA clones) by two bioinformatic N-myristoylation prediction systems, NMT-The MYR Predictor and Myristoylator. After database searches to exclude known human N-myristoylated proteins, 37 cDNA clones were selected as potential human N-myristoylated proteins. The susceptibility of these cDNA clones to protein N-myristoylation was first evaluated using fusion proteins in which the N-terminal ten amino acid residues were fused to an epitope-tagged model protein. Then, protein N-myristoylation of the gene products of full-length cDNAs was evaluated by metabolic labeling experiments both in an insect cell-free protein synthesis system and in transfected human cells. As a result, the products of 13 cDNA clones (FBXL7, PPM1B, SAMM50, PLEKHN, AIFM3, C22orf42, STK32A, FAM131C, DRICH1, MCC1, HID1, P2RX5, STK32B) were found to be human N-myristoylated proteins. Analysis of the role of protein N-myristoylation on the intracellular localization of SAMM50, a mitochondrial outer membrane protein, revealed that protein N-myristoylation was required for proper targeting of SAMM50 to mitochondria. Thus, the strategy used in this study is useful for the identification of physiologically important human N-myristoylated proteins from human cDNA resources.
Takamitsu, Emi; Otsuka, Motoaki; Haebara, Tatsuki; Yano, Manami; Matsuzaki, Kanako; Kobuchi, Hirotsugu; Moriya, Koko; Utsumi, Toshihiko
2015-01-01
To identify physiologically important human N-myristoylated proteins, 90 cDNA clones predicted to encode human N-myristoylated proteins were selected from a human cDNA resource (4,369 Kazusa ORFeome project human cDNA clones) by two bioinformatic N-myristoylation prediction systems, NMT-The MYR Predictor and Myristoylator. After database searches to exclude known human N-myristoylated proteins, 37 cDNA clones were selected as potential human N-myristoylated proteins. The susceptibility of these cDNA clones to protein N-myristoylation was first evaluated using fusion proteins in which the N-terminal ten amino acid residues were fused to an epitope-tagged model protein. Then, protein N-myristoylation of the gene products of full-length cDNAs was evaluated by metabolic labeling experiments both in an insect cell-free protein synthesis system and in transfected human cells. As a result, the products of 13 cDNA clones (FBXL7, PPM1B, SAMM50, PLEKHN, AIFM3, C22orf42, STK32A, FAM131C, DRICH1, MCC1, HID1, P2RX5, STK32B) were found to be human N-myristoylated proteins. Analysis of the role of protein N-myristoylation on the intracellular localization of SAMM50, a mitochondrial outer membrane protein, revealed that protein N-myristoylation was required for proper targeting of SAMM50 to mitochondria. Thus, the strategy used in this study is useful for the identification of physiologically important human N-myristoylated proteins from human cDNA resources. PMID:26308446
An All Silicon Feedhorn-Coupled Focal Plane for Cosmic Microwave Background Polarimetry
NASA Technical Reports Server (NTRS)
Hubmayr, J.; Appel, J. W.; Austermann, J. E.; Beall, J. A.; Becker, D.; Benson, B. A.; Bleem, L. E.; Carlstrom, J. E.; Chang, C. L.; Cho, H. M.;
2011-01-01
Upcoming experiments aim to produce high fidelity polarization maps of the cosmic microwave background. To achieve the required sensitivity, we are developing monolithic, feedhorn-coupled transition edge sensor polarimeter arrays operating at 150 GHz. We describe this focal plane architecture and the current status of this technology, focusing on single-pixel polarimeters being deployed on the Atacama B-mode Search (ABS) and an 84-pixel demonstration feedhorn array backed by four 10-pixel polarimeter arrays. The feedhorn array exhibits symmetric beams, cross-polar response less than -23 dB and excellent uniformity across the array. Monolithic polarimeter arrays, including arrays of silicon feedhorns, will be used in the Atacama Cosmology Telescope Polarimeter (ACTPol) and the South Pole Telescope Polarimeter (SPTpol) and have been proposed for upcoming balloon-borne instruments.
Advanced imaging research and development at DARPA
NASA Astrophysics Data System (ADS)
Dhar, Nibir K.; Dat, Ravi
2012-06-01
Advances in imaging technology have huge impact on our daily lives. Innovations in optics, focal plane arrays (FPA), microelectronics and computation have revolutionized camera design. As a result, new approaches to camera design and low cost manufacturing is now possible. These advances are clearly evident in visible wavelength band due to pixel scaling, improvements in silicon material and CMOS technology. CMOS cameras are available in cell phones and many other consumer products. Advances in infrared imaging technology have been slow due to market volume and many technological barriers in detector materials, optics and fundamental limits imposed by the scaling laws of optics. There is of course much room for improvements in both, visible and infrared imaging technology. This paper highlights various technology development projects at DARPA to advance the imaging technology for both, visible and infrared. Challenges and potentials solutions are highlighted in areas related to wide field-of-view camera design, small pitch pixel, broadband and multiband detectors and focal plane arrays.
NASA Technical Reports Server (NTRS)
Miller, Timothy M.; Costen, Nick; Allen, Christine
2007-01-01
This conference poster reviews the Indium hybridization of the large format TES bolometer arrays. We are developing a key technology to enable the next generation of detectors. That is the Hybridization of Large Format Arrays using Indium bonded detector arrays containing 32x40 elements which conforms to the NIST multiplexer readout architecture of 1135 micron pitch. We have fabricated and hybridized mechanical models with the detector chips bonded after being fully back-etched. The mechanical support consists of 30 micron walls between elements Demonstrated electrical continuity for each element. The goal is to hybridize fully functional array of TES detectors to NIST readout.
Clinical applications of penetrating neural interfaces and Utah Electrode Array technologies
NASA Astrophysics Data System (ADS)
Normann, Richard A.; Fernandez, Eduardo
2016-12-01
This paper briefly describes some of the recent progress in the development of penetrating microelectrode arrays and highlights the use of two of these devices, Utah electrode arrays and Utah slanted electrode arrays, in two therapeutic interventions: recording volitional skeletal motor commands from the central nervous system, and recording motor commands and evoking somatosensory percepts in the peripheral nervous system (PNS). The paper also briefly explores other potential sites for microelectrode array interventions that could be profitably pursued and that could have important consequences in enhancing the quality of life of patients that has been compromised by disorders of the central and PNSs.
ADGO: analysis of differentially expressed gene sets using composite GO annotation.
Nam, Dougu; Kim, Sang-Bae; Kim, Seon-Kyu; Yang, Sungjin; Kim, Seon-Young; Chu, In-Sun
2006-09-15
Genes are typically expressed in modular manners in biological processes. Recent studies reflect such features in analyzing gene expression patterns by directly scoring gene sets. Gene annotations have been used to define the gene sets, which have served to reveal specific biological themes from expression data. However, current annotations have limited analytical power, because they are classified by single categories providing only unary information for the gene sets. Here we propose a method for discovering composite biological themes from expression data. We intersected two annotated gene sets from different categories of Gene Ontology (GO). We then scored the expression changes of all the single and intersected sets. In this way, we were able to uncover, for example, a gene set with the molecular function F and the cellular component C that showed significant expression change, while the changes in individual gene sets were not significant. We provided an exemplary analysis for HIV-1 immune response. In addition, we tested the method on 20 public datasets where we found many 'filtered' composite terms the number of which reached approximately 34% (a strong criterion, 5% significance) of the number of significant unary terms on average. By using composite annotation, we can derive new and improved information about disease and biological processes from expression data. We provide a web application (ADGO: http://array.kobic.re.kr/ADGO) for the analysis of differentially expressed gene sets with composite GO annotations. The user can analyze Affymetrix and dual channel array (spotted cDNA and spotted oligo microarray) data for four species: human, mouse, rat and yeast. chu@kribb.re.kr http://array.kobic.re.kr/ADGO.
Betts, Guy N J; Eustace, Amanda; Patiar, Shalini; Valentine, Helen R; Irlam, Joely; Ramachandran, Anassuya; Merve, Ashirwad; Homer, Jarrod J; Möller-Levet, Carla; Buffa, Francesca M; Hall, Gillian; Miller, Crispin J; Harris, Adrian L; West, Catharine M L
2013-01-01
Tumour hypoxia is associated with a poor prognosis in head and neck squamous cell carcinoma (HNSCC), however there is no accepted method for assessing hypoxia clinically. We aimed to conduct a technical validation of a hypoxia gene expression signature using the TaqMan Low Density Array (TLDA) platform to investigate if this approach reliably identified hypoxic tumours. Tumour samples (n=201) from 80 HNSCC patients were collected prospectively from two centres. Fifty-three patients received pimonidazole prior to surgery. TaqMan Low Density Array-Hypoxia Scores (TLDA-HS) were obtained by quantitative real-time PCR (qPCR) using a 25-gene signature and customised TLDA cards. Assay performance was assessed as coefficient of variation (CoV). The assay was sensitive with linear reaction efficiencies across a 4 log(10) range of inputted cDNA (0.001-10 ng/μl). Intra- (CoV=6.9%) and inter- (CoV=2.0%) assay reproducibility were excellent. Intra-tumour heterogeneity was lower for TLDA-HS (23.2%) than for pimonidazole (67.2%) or single gene measurements of CA9 (62.2%), VEGFA (45.0%) or HIG2 (39.4%). TLDA-HS in HNSCC cell lines increased with decreasing pO(2). TLDA-HS correlated with Affymetrix U133 Plus 2.0 microarray HS (p<0.01) and positive pimonidazole scores (p=0.005). Gene expression measurements of hypoxia using a 25-gene signature and TLDA cards are sensitive, reproducible and associated with lower intra-tumour heterogeneity than assaying individual genes or pimonidazole binding. The approach is suitable for further assessment of prognostic and predictive capability in clinical trial material. Copyright © 2012 Elsevier Ltd. All rights reserved.
Wang, Y H; Garvin, D F; Kochian, L V
2001-09-01
A subtractive tomato (Lycopersicon esculentum) root cDNA library enriched in genes up-regulated by changes in plant mineral status was screened with labeled mRNA from roots of both nitrate-induced and mineral nutrient-deficient (-nitrogen [N], -phosphorus, -potassium [K], -sulfur, -magnesium, -calcium, -iron, -zinc, and -copper) tomato plants. A subset of cDNAs was selected from this library based on mineral nutrient-related changes in expression. Additional cDNAs were selected from a second mineral-deficient tomato root library based on sequence homology to known genes. These selection processes yielded a set of 1,280 mineral nutrition-related cDNAs that were arrayed on nylon membranes for further analysis. These high-density arrays were hybridized with mRNA from tomato plants exposed to nitrate at different time points after N was withheld for 48 h, for plants that were grown on nitrate/ammonium for 5 weeks prior to the withholding of N. One hundred-fifteen genes were found to be up-regulated by nitrate resupply. Among these genes were several previously identified as nitrate responsive, including nitrate transporters, nitrate and nitrite reductase, and metabolic enzymes such as transaldolase, transketolase, malate dehydrogenase, asparagine synthetase, and histidine decarboxylase. We also identified 14 novel nitrate-inducible genes, including: (a) water channels, (b) root phosphate and K(+) transporters, (c) genes potentially involved in transcriptional regulation, (d) stress response genes, and (e) ribosomal protein genes. In addition, both families of nitrate transporters were also found to be inducible by phosphate, K, and iron deficiencies. The identification of these novel nitrate-inducible genes is providing avenues of research that will yield new insights into the molecular basis of plant N nutrition, as well as possible networking between the regulation of N, phosphorus, and K nutrition.
NASA Astrophysics Data System (ADS)
Yon, J. J.; Dumont, G.; Goudon, V.; Becker, S.; Arnaud, A.; Cortial, S.; Tisse, C. L.
2014-06-01
Silicon-based vacuum packaging is a key enabling technology for achieving affordable uncooled Infrared Focal Plane Arrays (IRFPA) required by a promising mass market that shows momentum for some extensive consumer applications, such as automotive driving assistance, smart presence localization and building management. Among the various approaches studied worldwide, CEA, LETI in partnership with ULIS is committed to the development of a unique technology referred to as PLP (Pixel Level Packaging). In this PLP technology, each bolometer pixel is sealed under vacuum using a transparent thin film deposition on wafer. PLP operates as an array of hermetic micro caps above the focal plane, each enclosing a single microbolometer. In continuation of our on-going studies on PLP for regular QVGA IRFPAs, this paper emphasizes on the innate scalability of the technology which was successfully demonstrated through the development of an 80 × 80 pixel IRFPA. The relevance of the technology with regard to the two formats is discussed, considering both performance and cost issues. We show that the suboptimal fill factor inherent to the PLP arrangement is not so critical when considering smaller arrays preferably fitted for consumer applications. The discussion is supported with the electro-optical performance measurements of the PLP-based 80×80 demonstrator.
The potential impact of new power system technology on the design of a manned space station
NASA Technical Reports Server (NTRS)
Fordyce, J. S.; Schwartz, H. J.
1984-01-01
Larger, more complex spacecraft of the future such as a manned Space Station will require electric power systems of 100 kW and more, orders of magnitude greater than the present state of the art. Power systems at this level will have a significant impact on the spacecraft design. Historically, long-lived spacecraft have relied on silicon solar cell arrays, a nickel-cadmium storage battery and operation at 28 V dc. These technologies lead to large array areas and heavy batteries for a Space Station application. This, in turn, presents orbit altitude maintenance, attitude control, energy management and launch weight and volume constraints. Size (area) and weight of such a power system can be reduced if new higher efficiency conversion and lighter weight storage technologies are used. Several promising technology options including concentrator solar photovoltaic arrays, solar thermal dynamic and ultimately nuclear dynamic systems to reduce area are discussed. Also, higher energy storage systems such as nickel-hydrogen and the regenerative fuel cell (RFC) and higher voltage power distribution which add system flexibility, simplicity and reduce weight are examined. Emphasis is placed on the attributes and development status of emerging technologies that are sufficiently developed so that they could be available for flight use in the early to mid 1990's.
The potential impact of new power system technology on the design of a manned Space Station
NASA Technical Reports Server (NTRS)
Fordyce, J. S.; Schwartz, H. J.
1984-01-01
Larger, more complex spacecraft of the future such as a manned Space Station will require electric power systems of 100 kW and more, orders of magnitude greater than the present state of the art. Power systems at this level will have a significant impact on the spacecraft design. Historically, long-lived spacecraft have relied on silicon solar cell arrays, a nickel-cadmium storage battery and operation at 28 V dc. These technologies lead to large array areas and heavy batteries for a Space Station application. This, in turn, presents orbit altitude maintenance, attitude control, energy management and launch weight and volume constraints. Size (area) and weight of such a power system can be reduced if new higher efficiency conversion and lighter weight storage technologies are used. Several promising technology options including concentrator solar photovoltaic arrays, solar thermal dynamic and ultimately nuclear dynamic systems to reduce area are discussed. Also, higher energy storage systems such as nickel-hydrogen and the regenerative fuel cell (RFC) and higher voltage power distribution which add system flexibility, simplicity and reduce weight are examined. Emphasis placed on the attributes and development status of emerging technologies that are sufficiently developed so that they could be available for flight use in the early to mid 1990's.