172,662 research outputs found
VLF scattering from red sprites: application of numerical modelling
No full textRed sprites were discovered by chance in 1989 when a low-light TV system was pointed above an active thunderstorm. Red sprites are associated with columns of ionization in the Earth-ionosphere waveguide, from above the thunderstorm into the D region of the ionosphere. The ionized columns have been detected through “VLF sprites,” perturbations of the phase and/or amplitude of subionospheric VLF transmissions, which can be used to study the electrical properties of red sprites. There is extensive experimental evidence that VLF sprites may involve wide scattering angles and can produce back scattered radiation. Here we present a numerical and theoretical study of me scattering of subionospheric VLF transmissions caused by the plasma columns associated with red sprites. Comparison of the VLF scattering from sprites is made between a non-Born rigorous model which assumes the sprites are infinite columns of constant conductivity, and a three dimensional Born scattering code. Both formulations show excellent agreement with one another. The formulations predict VLF sprites similar to those experimentally observed for all scattering angles. This shows that the conclusions of previous studies into VLF sprites making use of the non-Born formulations of Rodger et al. [1997a, b] are valid. The modeling provides strong evidence that red sprite plasma is highly ionized in comparison with the ambient nighttime ionosphere, being nearly 5 orders of magnitude greater than the ambient at some heights
Metal Casting: Implementing the lost wax and waste mold gravity process of metal casting in the public school art program
No full textA Paper Submitted in Fulfillment of the Requirements in Problems in Art Education 295 by Rodger C. Hansen, August 1969.Hansen, Rodger C. (1969). Metal Casting: Implementing the lost wax and waste mold gravity process of metal casting in the public school art program. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/222631
Security police watching C-130 take off
No full textTaken at the end of the first Persian Gulf War in 1991, this photograph from the Rodger Cuccio Collection shows security police watching a C-130 take off from the Kuwait International Airport in Kuwait City. The 3rd Armored Division soldiers on board were bound for the United States. Rodger Cuccio was a member of the 356th Tactical Airlift Squadron stationed at Rickenbacker Air Force Base near Columbus. His unit, along with four others, was attached to the 907th Tactical Airlift Group, U.S. Airforce Reserve. This squadron, made up of over 250 servicemen and women, served in the Gulf War from January to June of 1991.
While in Kuwait, Cuccio’s unit flew over 2,000 sorties, hauled over 4,400 tons of cargo and moved more than 13,000 people during Operation Desert Storm. Additional missions of the 907th squadron included resupplying Kuwait City after its liberation, redeployment of troops from Iraq to Saudi Arabia following the signing of the United Nations peace treaty, and evacuation of Shiite Muslims from southern Iraq. The men and women of the 907th Tactical Airlift Group returned to Westover Air Force Base in Massachusetts on June 14, 1991, after 141 days overseas. Other photographs in the Cuccio Collection depict camp life for U.S. soldiers, old artillery and military aircraft, Kuwaiti refugees, and Kuwait City and the surrounding areas
Ruthenium polypyridyl complexes and their modes of interaction with DNA : is there a correlation between these interactions and the antitumor activity of the compounds?
No full textVarious interaction modes between a group of six ruthenium polypyridyl complexes and DNA have been studied using a number of spectroscopic techniques. Five mononuclear species were selected with formula [Ru(tpy) L1L2](2-n)?, and one closely related dinuclear cation of formula [{Ru(apy)(tpy)}2{l-H2N(CH2)6NH2}]4?. The ligand tpy is 2,20:60,200-terpyridine and the ligand L1 is a bidentate ligand, namely, apy (2,20-azobispyridine), 2-phenylazopyridine, or 2-phenylpyridinylmethylene amine. The ligand L2 is a labile monodentate ligand, being Cl-, H2O, or CH3CN. All six species containing a labile L2 were found to be able to coordinate to the DNA model base 9-ethylguanine by 1H NMR and mass spectrometry. The dinuclear cationic species, which has no positions available for coordination to a DNA base, was studied for comparison purposes. The interactions between a selection of four representative complexes and calf-thymus DNA were studied by circular and linear dichroism. To explore a possible relation between DNA-binding ability and toxicity, all compounds were screened for anticancer activity in a variety of cancer cell lines, showing in some cases an activity which is comparable to that of cisplatin. Comparison of the details of the compound structures, their DNA binding, and their toxicity allows the exploration of structure–activity relationships that might be used to guide optimization of the activity of agents of this class of compounds
Security police watching C-130 take off
No full textMilitary security police watch a C-130 take off with 3rd Armored Division soldiers aboard for their return trip to the United States at the end of the Persian Gulf War. This photograph, from the Rodger Cuccio Collection, was taken at Kuwait International Airport, Kuwait City, 1991. Rodger Cuccio was a member of the 356th Tactical Airlift Squadron stationed at Rickenbacker Air Force Base near Columbus. His unit, along with four others, was attached to the 907th Tactical Airlift Group, U.S. Airforce Reserve. This squadron, made up of over 250 servicemen and women, served in the Gulf War from January to June of 1991.
While in Kuwait, Cuccio’s unit flew over 2,000 sorties, hauled over 4,400 tons of cargo and moved more than 13,000 people during Operation Desert Storm. Additional missions of the 907th squadron included resupplying Kuwait City after its liberation, redeployment of troops from Iraq to Saudi Arabia following the signing of the United Nations peace treaty, and evacuation of Shiite Muslims from southern Iraq. The men and women of the 907th Tactical Airlift Group returned to Westover Air Force Base in Massachusetts on June 14, 1991, after 141 days overseas. Other photographs in the Cuccio Collection depict camp life for U.S. soldiers, old artillery and military aircraft, Kuwaiti refugees, and Kuwait City and the surrounding areas
Simulations of DNA coiling around a synthetic supramolecular cylinder that binds in the DNA major groove
No full textIn this work we present the results of a molecular simulation study of the interaction between a tetracationic bis iron((II)) supramolecular cylinder, [Fe-2(C25H20N4)(3)](4+), and DNA. This supramolecular cylinder has been shown to bind in the major groove of DNA and to induce dramatic coiling of the DNA. The simulations have been designed to elucidate the interactions that lead the cylinder to target the major groove and that drive the subsequent DNA conformational changes. Three sets of multi-nanosecond simulations have been performed: one of the uncomplexed d(CCCCCTTTTTCC)d(GGAAAAAGGGGG) dodecamer; one of this DNA complexed with the cylinder molecule; and one of this DNA complexed with a neutralised version of the cylinder. Coiling of the DNA was observed in the DNA-cylinder simulations, giving insight into the molecular level nature of the supramolecular coiling observed experimentally. The cylinder charge was found not to be essential for the DNA coiling, which implies that the DNA response is moderated by the short range interactions that define the molecular shape. Cylinder charge did, however, affect the integrity of the DNA duplex, to the extent that, under some circumstances, the tetracationic cylinder induced defects in the DNA base pairing at locations adjacent to the cylinder binding site
Ohio troops during Persian Gulf War photograph
No full textThis photograph, part of the Rodger Cuccio Collection, is of a group of firefighters from Marion, Ohio, and C-130 air crewmen from Columbus holding the Ohio flag. It was taken in Safwan, Iraq, during the first Persian Gulf War in 1991. Rodger Cuccio was a member of the 356th Tactical Airlift Squadron stationed at Rickenbacker Air Force Base near Columbus. His unit, along with four others, was attached to the 907th Tactical Airlift Group, U.S. Airforce Reserve. This squadron, made up of over 250 servicemen and women, served in the Gulf War from January to June of 1991.
While in Kuwait, Cuccio’s unit flew over 2,000 sorties, hauled over 4,400 tons of cargo and moved more than 13,000 people during Operation Desert Storm. Additional missions of the 907th squadron included resupplying Kuwait City after its liberation, redeployment of troops from Iraq to Saudi Arabia following the signing of the United Nations peace treaty, and evacuation of Shiite Muslims from southern Iraq. The men and women of the 907th Tactical Airlift Group returned to Westover Air Force Base in Massachusetts on June 14, 1991, after 141 days overseas. Other photographs in the Cuccio Collection depict camp life for U.S. soldiers, old artillery and military aircraft, Kuwaiti refugees, and Kuwait City and the surrounding areas
Shape effects on the activity of synthetic major-groove binding ligands
No full textIn this work we present the results of a molecular simulation study of two different tetracationic bis iron(II) supramolecular cylinders interacting with DNA. One cylinder has been shown to bind in the major groove of DNA and to induce dramatic coiling of the DNA; the second is a derivative of the first, with additional methyl groups attached so as to give a larger cylinder-radius. The simulations show that both cylinders bind strongly to the major groove of the DNA, and induce complex structural changes in A-T rich regions. Whereas the parent cylinder tends to bind along the major groove, the derivatised cylinder tends to twist so that only one end remains within the major groove. Both G-C rich and A-T rich binding sites for the derivatised cylinder are discussed. (c) 2006 Elsevier Inc. All rights reserved
Emeritus Professor Sylvia Rodger, AM: Australian occupational therapy champion and visionary
No full textEmeritus Professor Sylvia Rodger made a significant contribution to the occupational therapy profession on the local, national and international stage. Starting her career in 1981, she was a clinician working with children with a variety of issues (including Developmental Coordination Disorder [DCD], Autism Spectrum Disorders [ASD], developmental delay to name a few) and their families, a leading occupational therapy educator, and a researcher who has been instrumental in establishing a national research centre for individuals living with ASD. In addition, Emeritus Professor Rodger demonstrated expertise in higher education teaching, learning and leadership, as well as mentoring and assisting the careers of early academics, educators, researchers and the future generation of occupational therapists. Emeritus Professor Rodger's work has been recognised by Occupational Therapy Australia, the American Occupational Therapy Association, the Australian higher education sector, and peak research funding organisations. In this article we will present a broad overview of Emeritus Professor Rodger's career and accomplishments, highlighting her contributions to the occupational therapy profession both nationally and internationally.No Full Tex
Acute hospitals: A challenging context for occupation-centred practice with children
No full textMolineux (2004) described the translation of an occupational focus from theory into practice as being simultaneously simple and diffi cult. This diffi culty is rooted, he suggested, in the very nature of most modern work environments and particularly reductionist medical settings. Acute medical settings pose specifi c challenges to occupational therapists who aspire to occupation-centred practice (Baum, Berg, Seaton, & White, 2002; Pollard & Walsh, 2000). Yet there appears to be limited information available to guide and support therapists in reconciling an occupation-centred practice paradigm with the (often incongruous) acute orientation of hospitals, especially with children. This chapter aims to explore how occupational therapists in children’s hospitals describe, justify and implement occupation- centred practice despite the inherent challenges of their working...
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