4,505 research outputs found
Morphological Abnormalities in Illinois Cricket Frogs, Acris crepitans, 1968-71
Reports of malformed amphibians have been increasing, including external deformities such as missing or extra arms and legs, missing eyes and mandibles, and internal abnormalities involving the bladder, digestive system, and testes. Natural phenomena such as limb amputations during predation attempts by other animals, parasitism, xenobiotic chemicals (herbicides, insecticides, fertilizers and others), and UV-B or other radiation (either directly or indirectly by triggering production of toxicants from nontoxic chemicals) have all been linked to amphibian abnormalities. From 1968-71, I studied the natural history, effective breeding size, and seasonal, annual, and geographic variation in color morph frequencies of cricket frogs (Acris crepitans) in Illinois to evaluate the potential adaptive significance of polymorphism in the species. Cricket frogs from seven different populations were marked for later identification and followed for three years. Additionally, cricket frogs from 28 other populations in Illinois were sampled at least once. A detailed review of my field notes showed that 30 years ago the frequency of abnormalities recorded throughout Illinois was 0. 39% and that most oddities involved missing arms and legs (0.32%) rather than extra limbs (0.07%). Missing limbs may reflect attempted predation by other animals while extra limbs would indicate developmental errors. Only seven confirmed deformities (extra or deformed arms, deformed digits, underdeveloped mouth) were recorded in almost 10,000 frogs examined
KSC Facilities Status and Planned Management Operations
This is a status report on the facilities and planned operations at the Kennedy Space Center that will support Space Shuttle launches, the first of which is now scheduled for late 1979. The facilities are essentially complete, with all new construction and modifications to existing buildings almost finished. Some activity is still in progress at Pad A and on the Mobile Launcher, due to changes in requirements, but is not expected to impact the launch schedule. The installation and testing of the ground checkout equipment that will be used to test the fIight hardware is now in work. The Launch Processing System is currently supporting the development of the applications software that will perform the testing of this fIight hardware.
The Shuttle Program is unique to past manned space programs in that very tight budgetary constraints have been imposed in an effort to keep the costs low. For KSC, this means adopting a philosophy of launch-to-cost. In an era of routine space flight, this presents a very real challenge to management; the necessity of controlling costs while maintaining tight schedules. An overview of how this management challenge is to be met will be presented
Electronic Structures of Group 9 Metallocorroles with Axial Ammines
The electronic structures of metallocorroles (tpfc)M(NH_3)_2 and (tfc)M(NH_3)_2 (tpfc is the trianion of 5,10,15-(tris)pentafluorophenylcorrole, tfc is the trianion of 5,10,15-trifluorocorrole, and M = Co, Rh, Ir) have been computed using first principles quantum mechanics [B3LYP flavor of Density Functional Theory (DFT) with Poisson−Boltzmann continuum solvation]. The geometry was optimized for both the neutral systems (formal M^(III) oxidation state) and the one-electron oxidized systems (formally M^(IV)). As expected, the M^(III) systems have a closed shell d^6 configuration; for all three metals, the one-electron oxidation was calculated to occur from a ligand-based orbital (highest occupied molecular orbital (HOMO) of B_1 symmetry). The ground state of the formal M^(IV) system has M^(III)-Cπ character, indicating that the metal remains d^6, with the hole in the corrole π system. As a result the calculated M^(IV/III) reduction potentials are quite similar (0.64, 0.67, and 0.56 V vs SCE for M = Ir, Rh and Co, respectively), whereas the differences would have been large for purely metal-based oxidations. Vertically excited states with substantial metal character are well separated from the ground state in one-electron-oxidized cobalt (0.27 eV) and rhodium (0.24 eV) corroles, but become closer in energy in the iridium (0.15 eV) analogues. The exact splittings depend on the chosen functional and basis set combination and vary by ~0.1 eV
1863-12-29 Captain Robert Gray forwards a petition to Governor Cony
https://digitalmaine.com/cw_me_4th_regiment_corr/1467/thumbnail.jp
1863-03-18 Captain Robert H. Gray and other officers recommend commission for Charles S. McCobb
https://digitalmaine.com/cw_me_4th_regiment_corr/1365/thumbnail.jp
1864-01-17 Major Robert Gray requests the commission of Nathaniel Robbins be revoked and Henry Tibbetts be commissioned as 1st Lieutenant
https://digitalmaine.com/cw_me_4th_regiment_corr/1472/thumbnail.jp
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