5,365 research outputs found
Remarks on imperfections of axially loaded cylinders
Imperfections of axially loaded cylindrical shell
Volatile metal deposits on lunar soils: Relation to volcanism
Parallel leaching and volatilization experiments conducted on lunar samples and similar experiments on sphalerite do not supply the information needed to resolve the question of the chemical nature of pb 204, Zn, Bi and Tl deposits on lunar soil surfaces. It is proposed that in Apollo 17 mare and terra soils and fractions of pb 204, Zn and Tl that are insoluble under mild, hot pH 5HNO3, leaching conditions and involatile at 600 C were originally surface deposits which became immobilized by migration into the silicate substrate or by chemisorption. Only Bi is predominantly indigenous. The implication is also that the soils over their respective times of evolution were exposed to heavy metal vapors or that an episodic exposure occurred after they had evolved. A sequence of events is proposed to account for orange 74220 and black 74001 glasses by lava fountaining and for soil 74241 as tephra from an explosive volcanic eruption
To the End of the World with You
VERSE 1A wonderful power has entered my life,It came when your eyes reached my heart.I live in a glorious dreamland with you,A kingdom of love set apart,And all of my joys are because I love you,For love is my life and my all,And ages to be, only mean you to me,To love until Heaven’s roll call.
REFRAINTho’Stars of hope are burning low, dear,And all the world is filled with woe, dear,My heart will bid me go, dearTo the end of the world with you!end of the world with you!
VERSE 2I dreamed of your coming and longed for you so,I built you a shrine in my love,And all that my fancy had dreamed, love, of youYou brought when you came from above.Without you I’d be as a lost mountain stream,That never has reached to the sea;Eternity’s all seems as ages too small, To live out my longing for thee.
REFRAI
Love Me and the World Is Mine
[Verse 1] I wander on as in a dream, My goal a paradise must be, For there an angel waits ‘twould seem, Yet lo’ dear heart, ‘tis only thee. Suns may shine to light my way dear, Wealth be mine for aye dear, Queens may pledge their riches too; Yet the world would still be lonely, With such virtues only, Life to me dear, means just you.
[Chorus] I care not for the stars that shine, I dare not hope to e’er be thine, I only know I love you,Love me, and the world is mine.
[Verse 2] My soul soars on to realms above Thro’ mystic lands it seems to go, As if ‘twere borne on wings of love, The love that only angels know. Your bright eyes like beacons guide me, Thro’ the clouds that hide me, Would that they were mine to woo; All the joys the world may hold dear, Lands and wealth untold dear, Seem as naught compared to you.
[Chorus
RSRM Segment Train Derailment and Recovery
On May 2, 2007, a freight train carrying segments of the space shuttle's solid rocket boosters derailed in Myrtlewood, Alabama, after a rail trestle collapsed. The train was carrying Reusable Solid Rocket Motors (RSRM) 98 center and forward segments (STS-120) and RSRM 99 aft segments (STS-122). Initially, it was not known if the segments had been seriously damaged. Four segments dropped approximately 10 feet when the trestle collapsed and one of those four rolled off the track onto its side. The exit cones and the other four segments, not yet on the trestle, remained on solid ground. ATK and NASA immediately dispatched an investigation and recovery team to determine the safety of the situation and eventually the usability of the segments and exit cones for flight. Instrumentation on each segment provided invaluable data to determine the acceleration loads imparted into each loaded segment and exit cone. This paper details the incident, recovery plan and the team work that created a success story that ended with the safe launch of STS120 using the four center segments and the launch of STS122 using the Aft exit cones assemblies
Note and Comment
Legislative Power to Restrict Freedom of Labor Contracts -The struggle between the police power of the legislature and the nineteenth century idea of due process of law continues unremittingly. That increasing social necessities and a more comprehensive and perfect conception of justice have resulted in recent years in restricting the due process clauses in federal and state constitutions to their historically and logically more correct meaning and scope there can be no doubt. Scores, if not hundreds, of decisions by our courts and conspicuously those of the United States Supreme Court have shown complete recognition of the fact that the formalism and the extreme individualism of earlier periods can only produce dangerous economic and social maladjustments in the complex and interlocking organization of our modern society
Base excision repair apurinic/apyrimidinic endonucleases in apicomplexan parasite Toxoplasma gondii
DNA repair is essential for cell viability and proliferation. In addition to reactive oxygen produced as a byproduct of their own metabolism, intracellular parasites also have to manage oxidative stress generated as a defense mechanism by the host. The spontaneous loss of DNA bases due to hydrolysis and oxidative DNA damage in intracellular parasites is great, but little is known about the type of DNA repair machineries that exist in these early-branching eukaryotes. However, it is clear, processes similar to DNA base excision repair (BER) must exist to rectify spontaneous and host-mediated damage in Toxoplasma gondii. Here we report that T. gondii, an opportunistic protozoan pathogen, possesses two apurinic/apyrimidinic (AP) endonucleases that function in DNA BER. We characterize the enzymatic activities of Toxoplasma exonuclease III (ExoIII, or Ape1) and endonuclease IV (EndoIV, or Apn1), designated TgAPE and TgAPN, respectively. Over-expression of TgAPN in Toxoplasma conferred protection from DNA damage, and viable knockouts of TgAPN were not obtainable. We generated an inducible TgAPN knockdown mutant using a ligand-controlled destabilization domain to establish that TgAPN is critical for Toxoplasma to recover from DNA damage. The importance of TgAPN and the fact that humans lack any observable APN family activity highlights TgAPN as a promising candidate for drug development to treat toxoplasmosis
Deployment of spacecraft appendages and temperature control of experiments Final technical report
Deployment dynamics and temperature control of spacecraft solar panel array and X ray telescop
Highly conserved gene order and numerous novel repetitive elements in genomic regions linked to wing pattern variation in Heliconius butterflies
This is the final version of the article. Available from the publisher via the DOI in this record.BACKGROUND: With over 20 parapatric races differing in their warningly colored wing patterns, the butterfly Heliconius erato provides a fascinating example of an adaptive radiation. Together with matching races of its co-mimic Heliconius melpomene, H. erato also represents a textbook case of Müllerian mimicry, a phenomenon where common warning signals are shared amongst noxious organisms. It is of great interest to identify the specific genes that control the mimetic wing patterns of H. erato and H. melpomene. To this end we have undertaken comparative mapping and targeted genomic sequencing in both species. This paper reports on a comparative analysis of genomic sequences linked to color pattern mimicry genes in Heliconius. RESULTS: Scoring AFLP polymorphisms in H. erato broods allowed us to survey loci at approximately 362 kb intervals across the genome. With this strategy we were able to identify markers tightly linked to two color pattern genes: D and Cr, which were then used to screen H. erato BAC libraries in order to identify clones for sequencing. Gene density across 600 kb of BAC sequences appeared relatively low, although the number of predicted open reading frames was typical for an insect. We focused analyses on the D- and Cr-linked H. erato BAC sequences and on the Yb-linked H. melpomene BAC sequence. A comparative analysis between homologous regions of H. erato (Cr-linked BAC) and H. melpomene (Yb-linked BAC) revealed high levels of sequence conservation and microsynteny between the two species. We found that repeated elements constitute 26% and 20% of BAC sequences from H. erato and H. melpomene respectively. The majority of these repetitive sequences appear to be novel, as they showed no significant similarity to any other available insect sequences. We also observed signs of fine scale conservation of gene order between Heliconius and the moth Bombyx mori, suggesting that lepidopteran genome architecture may be conserved over very long evolutionary time scales. CONCLUSION: Here we have demonstrated the tractability of progressing from a genetic linkage map to genomic sequence data in Heliconius butterflies. We have also shown that fine-scale gene order is highly conserved between distantly related Heliconius species, and also between Heliconius and B. mori. Together, these findings suggest that genome structure in macrolepidoptera might be very conserved, and show that mapping and positional cloning efforts in different lepidopteran species can be reciprocally informative.The work was funded by U.S. National Science Foundation grants IOB
0344705 and DEB 0715096 to WOM. The H. erato BAC library was constructed
by C. Wu, H. Zhang (TAMU), and M. R. Goldsmith (URI) under
NSF Grant IBN-0208388. In addition, the Computational Biology Service
Unit at Cornell University, which is partially funded by Microsoft Corporation,
provided bioinformatics support for our analysis of genomic repeat
structure. AFLP analysis and sequencing of PCR products was carried out
at the Sequencing and Genotyping Center at the University of Puerto RicoRio
Piedras. We thank Nicola Flanagan, Alexandra Tobler, Karla Maldonado,
Jenny Acevedo Gonzales, Hector Alejandro Merchan, Yhadi Cotto,
Kelitt Santiago and Felix Araujo Perez for help in rearing and maintaining
butterfly stocks. Finally, a special thanks to Daniel P. Lindstrom for his support
and helpful suggestions during manuscript preparation
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