Development of carbon dioxide laser doppler instrumentation detection of clear air turbulence

The analytical, experimental, and developmental aspects of an airborne, pulsed, carbon dioxide laser-optical radar system are described. The laser detects clear air turbulence and performs Doppler measurements of this air-motion phenomenon. Conclusions and recommendations arising from the development of the laser system are presented

Neutral carbon in the Egg Nebula (AFGL 2688)

A search for sub-mm C I emission from seven stars that are surrounded by dense molecular gas shells led to the detection, in the case of the "Egg Nebula' (AFGL 2688), of an 0.9 K line implying a C I/CO value greater than 5. The material surrounding this star must be extremely carbon-rich, and it is suggested that the apparently greater extent of the C I emission region may be due to the effects of the galactic UV field on the shell's chemistry, as suggested by Huggins and Glassgold (1982)

Nanoparticle growth following photochemical α‐ and β‐pinene oxidation at Appledore Island during International Consortium for Research on Transport and Transformation/Chemistry of Halogens at the Isles of Shoals 2004

Nanoparticle events were observed 48 times in particle size distributions at Appledore Island during the International Consortium for Atmospheric Research on Transport and Transformation/Chemistry of Halogens on the Isles of Shoals (ICARTT/CHAiOS) field campaign from 2 July to 12 August of 2004. Eighteen of the nanoparticle events showed particle growth and occurred during mornings when peaks in mixing ratios of α‐ and β‐pinene and ozone made production of condensable products from photochemical oxidation probable. Many pollutants and other potential precursors for aerosol formation were also at elevated mixing ratios during these events, including NO, HNO3, NH3, HCl, propane, and several other volatile organic carbon compounds. There were no consistent changes in particle composition, although both submicron and supermicron particles included high maximum concentrations of methane sulfonate, sulfate, iodide, nitrate, and ammonium during these events. Nanoparticle growth continued over several hours with a nearly linear rate of increase of diameter with time. The observed nanoparticle growth rates varied from 3 to 13 nm h−1. Apparent nanoparticle aerosol mass fractions (yields) were estimated to range from less than 0.0005 to almost 1 using α‐ and β‐pinene as the presumed particle source. These apparent high aerosol mass fractions (yields) at low changes in aerosol mass are up to two orders of magnitude greater than predictions from extrapolated laboratory parameterizations and may provide a more accurate assessment of secondary organic aerosol formation for estimating the growth of nanoparticles in global models

HASSKARL'S CINCHONA BARKS 1. HISTORICAL REVIEW

The preliminary results of alkaloid analyses of Hasskaii's cinchona bark collection, made in Peru in 1852/3' is given, and the identity and historical aspects of the material discussed in respect of the role the plants played in the Javanese plantations

L1551NE - Discovery of a Binary Companion

L1551NE is a very young (class 0 or I) low-mass protostar located close to the well-studied L1551 IRS5. We present here evidence, from 1.3mm continuum interferometric observations at ~1'' resolution, for a binary companion to L1551NE. The companion, whose 1.3mm flux density is ~1/3 that of the primary component, is located 1.43'' (~230 A.U. at 160pc) to the southeast. The millimeterwave emission from the primary component may have been just barely resolved, with deconvolved size ~0.82"x0.70" (~131x112 A.U.). The companion emission was unresolved (<100 A.U.). The pair is embedded within a flattened circum-binary envelope of size ~5.4'' x 2.3'' (~860 x 370 A.U.). The masses of the three components (i.e. from the cicumstellar material of the primary star and its companion, and the envelope) are approximately 0.044, 0.014 and 0.023 Mo respectively.Comment: 8 pages, 1 figur

Focused laser Doppler velocimeter

A system for remotely measuring velocities present in discrete volumes of air is described. A CO2 laser beam is focused by a telescope at such a volume, a focal volume, and within the focusable range, near field, of the telescope. The back scatter, or reflected light, principally from the focal volume, passes back through the telescope and is frequency compared with the original frequency of the laser, and the difference frequency or frequencies represent particle velocities in that focal volume

Remote detection of trailing vortices, task 3, modification 3

The operation of a frequency tracker for use with the laser Doppler velocimeter (LDV) is reported. Topics discussed include: laser beam profile, lens matching, and LDV resolution data. It is concluded that the LDV provides good ground wind signals. The loss in sensitivity of the cavity system at high frequencies is partly compensated by an increase in the scattering cross section of the atmosphere due to dust

Hypocretin underlies the evolution of sleep loss in the Mexican cavefish

The duration of sleep varies dramatically between species, yet little is known about the genetic basis or evolutionary factors driving this variation in behavior. The Mexican cavefish, Astyanax mexicanus, exists as surface populations that inhabit rivers, and multiple cave populations with convergent evolution on sleep loss. The number of Hypocretin/Orexin (HCRT)-positive hypothalamic neurons is increased significantly in cavefish, and HCRT is upregulated at both the transcript and protein levels. Pharmacological or genetic inhibition of HCRT signaling increases sleep in cavefish, suggesting enhanced HCRT signaling underlies the evolution of sleep loss. Ablation of the lateral line or starvation, manipulations that selectively promote sleep in cavefish, inhibit hcrt expression in cavefish while having little effect on surface fish. These findings provide the first evidence of genetic and neuronal changes that contribute to the evolution of sleep loss, and support a conserved role for HCRT in sleep regulation

The Ursinus Weekly, April 3, 1975

Someone old, someone new • Come to Ursinus: Land of the Pennsylvania Dutch • CCC student success seen • Newman Club • The Birds • Free, but show invitations • Editorial: Visitation - time for reality? • Letter to the editor: Breakage reply • Gymnastics • Record review: For earth below, Robin Trower • Wanted: More Lantern contributors • Spring sports special: 1975! • 1975 Ursinus baseball outlook • 1975 track prospectus • Another season, another title! • A.L. spotlight • Interview: Pat Williams • National League previewhttps://digitalcommons.ursinus.edu/weekly/1033/thumbnail.jp

Why Do We Fall? Using Experiences of Failure to Design Case Libraries

Instructional designers can support ill-structured problem solving through case libraries that detail domain-specific principles. In this design project, case libraries were employed in an undergraduate sales management course to contextualize knowledge and describe the ill-structured nature of how solutions are derived to solve authentic problems. Whereas many learning environments employ examples of model behavior (Jonassen, 2011), this instructional design was innovative in that the case libraries consisted of sales management failure experiences as the means to facilitate learning. The failure cases embedded within the learning environment engendered design tensions on multiple levels throughout the instructional design. Specifically, this article discusses the issues of engaging the subject matter expert (SME) to talk about failure cases and subsequent challenges to translate the experiences into meaningful learning resources for ill-structured problem solving. Other challenges included how to strategically design the learning environment so that the case library was available at the optimal time for the learners. The design case concludes with a reflection upon the process