Analysis of MSFC ground-based Doppler lidar data

Analysis of data collected during the participation of the MSFC 10.6 micron pulsed Doppler lidar system (DLS) in the Joint Airport Weather Studies (JAWS) experiment is concluded. Observations from more than one Doppler lidar are combined to derive the three-dimensional Cartesian wind field. A comparison of radial velocity estimates at low elevations made by the MSFC lidar and the NCAR 5.5 cm Doppler radar revealed a substantial r.m.s. difference of 3 mls, and a mean difference of lmls. Detailed measurements of the horizontal wind fields and tropospheric backscattering were acquired at MSFC. These data are useful for defining future flight experiments, instrument design, and satellite DLS development

A Distinction Without A Difference: Vietnam, Sir Robert Thompson, and the Policing Failures of Vietnam

The scholarship analyzing the failure of the American involvement in Vietnam began even before the war finished. Whether the Orthodox School which considered the war unwinnable or the revisionist which argued there was a path to victory for the Americans, there have been libraries of tomes arguing who or what was to blame for the American defeat. An increased amount of scholarship recently has been written regarding the influence of British officer Sir Robert Thompson and his attempt to advise both the South Vietnamese and American war efforts. Thompson, who gained fame as one of the key leaders for the British victory over the Communist insurgency during the Malayan Emergency (1948-1960), became a prominent author and military strategist writing several books on counterinsurgency of which the principles are still used in modern warfare. The question this paper asks is exploring further in the Thompsonian scholarship as regards why America was unsuccessful in the Vietnam Conflict. While many have declared Thompson as an ignored military savior in answering this question, there has been little focus on Thompson’s stressing constabulary or colonial policing as the main effort in the counterinsurgency fight. Malaya, as a British colony, had a strong and effective colonial police force which was instrumental in defeating the Communist insurgency. While Vietnam was also a former colony, they had lost the French gendarmerie forces prior to independence. This paper explores the failure of France, the United States, and even Thompson himself in developing a proper constabulary type police force to stop the Vietnamese Communist insurgency. While France had their colonial police dismantled and neglected through World War II and post-colonial independence, the Americans were simply ignorant of understanding the purpose of a constabulary force, creating either a civilian type police force or infantry units. Thompson, despite writing books stressing the importance of paramilitary policing could not convince the Americans that counterinsurgency is won through an effective paramilitary police force. This paper argues Thompsonian Vietnam analysis needs more focus on the failures of the South Vietnam policing strategy

Positioning and Aligning the 250 Ton Solid Rocket Motors for Titan IIIC

In the Integrate-Transfer-Launch concept of Titan IIIC, each 120-inch solid rocket motor is first assembled on a support frame and then lifted at the base and moved about 70 feet to a precise position adjacent to the core vehicle. The positioning of the completed motor presented several unique problems because this was the first attempt in any space program to transfer a vertical solid motor weighing 500,000 pounds, measuring 10 feet in diameter and 85 feet high, and having an eccentric center of gravity. The physical size of the positioning sling components and the magnitude of their stresses presented a series of special problems involving fabrication, shipment, installation and proof-load testing. Even the apparently simple function of disconnecting the sling from the crane hook became a problem because it involved removing a 10-inch diameter pin weighing 380 pounds, and performing this operation 180 feet above the floor. After the solid motors have been placed on the mobile launch platform they cannot be mated to the core vehicle until they have been moved both horizontally and vertically to within .020 inch, of the correct location. The difficulty in obtaining such, precision was compounded because parts of the core vehicle and its supports completely obstructed a direct line of sight between the interface points and left only a 4-inch vertical space in which to install and operate the alignment tools

The role of hydrogen in room-temperature ferromagnetism at graphite surfaces

We present a x-ray dichroism study of graphite surfaces that addresses the origin and magnitude of ferromagnetism in metal-free carbon. We find that, in addition to carbon $\pi$ states, also hydrogen-mediated electronic states exhibit a net spin polarization with significant magnetic remanence at room temperature. The observed magnetism is restricted to the top $\approx$10 nm of the irradiated sample where the actual magnetization reaches $\simeq 15$ emu/g at room temperature. We prove that the ferromagnetism found in metal-free untreated graphite is intrinsic and has a similar origin as the one found in proton bombarded graphite.Comment: 10 pages, 5 figures, 1 table, submitted to New Journal of Physic

Experimental Evidence for Two-Dimensional Magnetic Order in Proton Bombarded Graphite

We have prepared magnetic graphite samples bombarded by protons at low temperatures and low fluences to attenuate the large thermal annealing produced during irradiation. An overall optimization of sample handling allowed us to find Curie temperatures $T_c \gtrsim 350$ K at the used fluences. The magnetization versus temperature shows unequivocally a linear dependence, which can be interpreted as due to excitations of spin waves in a two dimensional Heisenberg model with a weak uniaxial anisotropy.Comment: 4 pages, 3 figure

Proton-induced magnetic order in carbon: SQUID measurements

In this work we have studied systematically the changes in the magnetic behavior of highly oriented pyrolytic graphite (HOPG) samples after proton irradiation in the MeV energy range. Superconducting quantum interferometer device (SQUID) results obtained from samples with thousands of localized spots of micrometer size as well on samples irradiated with a broad beam confirm previously reported results. Both, the para- and ferromagnetic contributions depend strongly on the irradiation details. The results indicate that the magnetic moment at saturation of spots of micrometer size is of the order of $10^{-10}$ emu.Comment: Invited contribution at ICACS2006 to be published in Nucl. Instr. and Meth. B. 8 pages and 6 figure

Effects of forest management practices on treefrog oviposition site choice

Abstract only availableGlobally, amphibian populations are declining faster than those of birds or mammals. Habitat destruction is considered the primary cause of these declines; however, what remains partly unexplored is the idea that some species may be more greatly affected than others by deforestation. Treefrogs (Family: Hylidae), because of their mobility, may be expected to circumvent disturbed habitats; however, because of their dependency on arboreal habitat, they may be adversely affected by different forms of forest management. As part of the LEAP (Land-Use Effects on Amphibian Populations) study, four forest management practices—clearcut with coarse woody debris (CWD) removed, clearcut with CWD retained, thinning of 25% basal area, and uncut forest—were implemented at four wetlands at the Savannah River Site. In May 2005, we placed wading pools 25 m into each treatment and allowed them to fill with rainwater. To monitor time to first oviposition event and to determine the number of events per treatment, pools were checked daily, eggs were counted, and tadpoles were raised to confirm that all eggs were indeed those of hylids. We measured water depth, canopy cover, and surrounding vegetation. These data will be analyzed to determine if suitable calling/breeding habitat (microhabitat) is a more reliable predictor of oviposition than treatment (macrohabitat). At three of the four wetlands, first oviposition events occurred in the thinning treatments, and second events occurred in the clearcuts with CWD retained. We found that more oviposition events also occurred in the thinning treatments (43%) and the clearcuts with CWD retained (33%) than in the clearcuts with CWD removed (13%) or the uncut forest controls (10%). One explanation for these findings is that hylids have evolved to locate openings in the forest canopy which could indicate a wetland or a fallen tree whose uprooting has caused an ephemeral pool to form.Life Sciences Undergraduate Research Opportunity Progra

A comparison of the magnetic properties of Proton- and Iron-implanted graphite

In this work we have investigated the changes of the magnetic properties of highly oriented pyrolytic graphite samples after irradiation either with $\sim 3 \times 10^{14}$ protons or $3.5 \times 10^{13} ... 3.5 \times 10^{14}$ iron ions with energies in the MeV range. Our results show that iron and proton irradiations can produce similar paramagnetic contributions depending on the implantation temperature. However, only protons induce a ferromagnetic effect.Comment: 4 pages with three figures. To be published in EPJ

Exploring the function of protein kinases in schistosomes: perspectives from the laboratory and from comparative genomics

Eukaryotic protein kinases are well conserved through evolution. The genome of Schistosoma mansoni, which causes intestinal schistosomiasis, encodes over 250 putative protein kinases with all of the main eukaryotic groups represented. However, unraveling functional roles for these kinases is a considerable endeavor, particularly as protein kinases regulate multiple and sometimes overlapping cell and tissue functions in organisms. In this article, elucidating protein kinase signal transduction and function in schistosomes is considered from the perspective of the state-of-the-art methodologies used and comparative organismal biology, with a focus on current advances and future directions. Using the free-living nematode Caenorhabditis elegans as a comparator we predict roles for various schistosome protein kinases in processes vital for host invasion and successful parasitism such as sensory behavior, growth and development. It is anticipated that the characterization of schistosome protein kinases in the context of parasite function will catalyze cutting edge research into host-parasite interactions and will reveal new targets for developing drug interventions against human schistosomiasis