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The Changing Dimensions of Japanese Security Issues
Presentation on post-Cold War security issues and international relations in Japan.
Delivered to the Japan Industry and Management of Technology Program (JIMT) at The University of Texas at Austin on August 11, 1999.IC2 Institut
Roscoe Reid Graham (1890 to 1948): a Canadian pioneer in general surgery.
Roscoe Reid Graham, a Canadian surgeon trained at the University of Toronto, was a true pioneer in the field of general surgery. Although he may be best known for his omental patch repair of perforated duodenal ulcers-often referred to as the Graham patch -he had a number of other significant accomplishments that decorated his surgical career. Dr. Graham is credited with being the first surgeon to successfully enucleate an insulinoma. He ventured to do an essentially brand new operation based solely on his patient\u27s symptoms and physical findings, a courageous move that even some of the most talented surgeons would shy away from. He also spent a large portion of his career dedicated to the study of rectal prolapse, working tirelessly to rid his patients of this awful affliction. He was recognized by a number of different surgical associations for his operative successes and was awarded membership to those both in Canada and the United States. Despite all of these accolades, Dr. Graham remained grounded and always fervent in his dedication to the patient and their presenting symptom(s), reminding us that to do anything more would be meddlesome. In an age when medical professionals are often all too eager to make unnecessary interventions, it is imperative that we look back at our predecessors such as Roscoe Reid Graham, for they will continually redirect us toward our one and only obligation: the patient
Deformation of the Cape Chignecto Pluton, Cobequid Highlands, Nova Scotia: thrusting at the Meguma-Avalon boundary
The Early Carboniferous Cape Chignecto pluton, at the western end of the Cobequid Highlands in the Avalon Terrane of Nova Scotia, consists predominantly of two-feldspar biotite granite. Intrusion of smaller diorite bodies locally melted and hybridized the granite. Diabase and microgranite dykes cut the plutons.
Much of the pluton has a flat-lying mylonitic foliation, with a mineral elongation lineation trending between north and west. Quartz is dynamically recrystallized, but feldspars show predominantly brittle deformation. The phiton was probably deformed under greenschist facies conditions, after cooling. C-S fabrics observed in the field, and tails on porphyroclasts seen in thin section, indicate northward overthrusting. The Hadrynian Jeffers Group is thrust over the south edge of the phiton in the Fowler Brook inlier. At its north edge, the pluton is probably thrust over volcanic rocks of die Fountain Lake Group. The deformation of the pluton is constrained by stratigraphic relationships and isotopic dates to a Namurian or possibly early Westphalian age.
Deformation within the pluton is correlated with Namurian uplift of the Cobequid and Caledonia Highlands. It records either transpression resulting from the curvature of the Meguma-Avalon boundary or a major component of convergent movement between the Meguma and Avalon terranes.
RÉSUMÉ
Le pluton de Cape Chignecto, daté du début du Carbonifere et situé à l'extremité occidentale des Monts Cobequid (Lanière d'Avalon, Nouvelle-Écosse), est formé en majeure partie de granite à biotite à deux feldspaths. Le granite subit une fonte et une hybridation locales lore de l’ intrusion de batis dioritiques de plus faibles dimensions. Des dykes de diabase et de microgranite recoupent les plutons.
La majeure partie du pluton présente une foliation mylonitique horizontale, avec une linétion d'éirement orientée entre le nord et l’ouesL On note une recristallisation dynamique du quartz mais la déformation des feldspaths est surtout fragile. Le pluton fut probablement déformé sous des conditions appartenant au faciès des schistes verts, et ce après son refroidissement. Des fabriques planaires C-S, observées sur le terrain, et des ombres de pression dissymdtriques, vues en lame mince, indiquent un charriage vers le nord. Le Groupe hadrynien de Jeffers chevauche l'extrémité méridionale du pluton dans la fenetre de Fowler Brook. A son extrémité septentrionale, le pluton chevauche probablement les volcanites du Groupe de Fountain Lake. Les relations stratigraphiqueset des datations radiométriques limitent l'âge de la déformation du pluton au Namurien ou possiblement au début du Westphalien.
On corrèle la déformation au sein du pluton avec la surrection namurienne des monts Cobequid et Caledonia. Cette déformation enregistre soil une transpression résultant de la cambrure de la jonction Meguma-Avalon, soil une forte composanle de mouvement convergent entre les lanières de Meguma et d* Avalon.
[Traduit par le journal
The gravitational wave rocket
Einstein's equations admit solutions corresponding to photon rockets. In
these a massive particle recoils because of the anisotropic emission of
photons. In this paper we ask whether rocket motion can be powered only by the
emission of gravitational waves. We use the double series approximation method
and show that this is possible. A loss of mass and gain in momentum arise in
the second approximation because of the emission of quadrupole and octupole
waves.Comment: 10 pages LaTe
Spotlight on the microbes that produce heat shock protein 90-targeting antibiotics
Heat shock protein 90 (Hsp90) is a promising cancer drug target as a molecular chaperone critical for stabilization and activation of several of the oncoproteins that drive cancer progression. Its actions depend upon its essential ATPase, an activity fortuitously inhibited with a very high degree of selectivity by natural antibiotics: notably the actinomycete-derived benzoquinone ansamycins (e.g. geldanamycin) and certain fungal-derived resorcyclic acid lactones (e.g. radicicol). The molecular interactions made by these antibiotics when bound within the ADP/ATP-binding site of Hsp90 have served as templates for the development of several synthetic Hsp90 inhibitor drugs. Much attention now focuses on the clinical trials of these drugs. However, because microbes have evolved antibiotics to target Hsp90, it is probable that they often exploit Hsp90 inhibition when interacting with each other and with plants. Fungi known to produce Hsp90 inhibitors include mycoparasitic, as well as plant-pathogenic, endophytic and mycorrhizal species. The Hsp90 chaperone may, therefore, be a prominent target in establishing a number of mycoparasitic (interfungal), fungal pathogen–plant and symbiotic fungus–plant relationships. Furthermore the Hsp90 family proteins of the microbes that produce Hsp90 inhibitor antibiotics are able to reveal how drug resistance can arise by amino acid changes in the highly conserved ADP/ATP-binding site of Hsp90
Processing of transcripts of a dimeric tRNA gene in yeast uses the nuclease responsible for maturation of the 3′ termini upon 5 S and 37 S precursor rRNAs
AbstractThe rna82 mutation of Saccharomyces cerevisiae inactivates an RNA processing activity responsible for maturation of 3′-terminal sequences upon 5 S and 37 S ribosomal RNA precursors. This study describes a difference in the processing of transcripts of an S. cerevisiae dimeric tRNA gene (tRNAArg-tRNAAsp) in RNA polymerase III in vitro transcription extracts prepared from rna82 and wild-type cells. The mutant extract accumulated additional processing intermediates containing tRNAArg sequences as compared to the extract from wild-type cells. The structure of these intermediates revealed a defect in removal of the 10 nucleotides left 3′ to the tRNAArg sequence by the RNase P cleavage immediately 5′ to tRNAAsp. This is the first demonstration of a mutational defect affecting maturation of 3′ sequences upon a eukaryotic tRNA precursor
Expressed in the yeast Saccharomyces cerevisiae, human ERK5 is a client of the Hsp90 chaperone that complements loss of the Slt2p (Mpk1p) cell integrity stress-activated protein kinase
ERK5 is a mitogen-activated protein (MAP) kinase regulated in human cells by diverse mitogens and stresses but also suspected of mediating the effects of a number of oncogenes. Its expression in the slt2Delta Saccharomyces cerevisiae mutant rescued several of the phenotypes caused by the lack of Slt2p (Mpk1p) cell integrity MAP kinase. ERK5 is able to provide this cell integrity MAP kinase function in yeast, as it is activated by the cell integrity signaling cascade that normally activates Slt2p and, in its active form, able to stimulate at least one key Slt2p target (Rlm1p, the major transcriptional regulator of cell wall genes). In vitro ERK5 kinase activity was abolished by Hsp90 inhibition. ERK5 activity in vivo was also lost in a strain that expresses a mutant Hsp90 chaperone. Therefore, human ERK5 expressed in yeast is an Hsp90 client, despite the widely held belief that the protein kinases of the MAP kinase class are non-Hsp90-dependent activities. Two-hybrid and protein binding studies revealed that strong association of Hsp90 with ERK5 requires the dual phosphorylation of the TEY motif in the MAP kinase activation loop. These phosphorylations, at positions adjacent to the Hsp90-binding surface recently identified for a number of protein kinases, may cause a localized rearrangement of this MAP kinase region that leads to creation of the Hsp90-binding surface. Complementation of the slt2Delta yeast defect by ERK5 expression establishes a new tool with which to screen for novel agonists and antagonists of ERK5 signaling as well as for isolating mutant forms of ERK5
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