Statement of Thomas R. Donahue Before the Commission on the Future of Worker-Management Relations

Includes recommendations to the Commission concerning changes in the National Labor Relations Act.Testimony_Donohue_090894.pdf: 177 downloads, before Oct. 1, 2020

Methane measurement by the Pioneer Venus large probe neutral mass spectrometer

The Pioneer Venus Large Probe Mass Spectrometer detected a large quantity of methane as it descended below 20 km in the atmosphere of Venus. Terrestrial methane and Xe-136, both originating in the same container and flowing through the same plumbing, were deliberately released inside the mass spectrometer for instrumental reasons. However, the Xe-136 did not exhibit behavior similar to methane during Venus entry, nor did CH4 in laboratory simulations. The CH4 was deuterium poor compared to Venus water and hydrogen. While the inlet to the mass spectrometer was clogged with sulfuric acid droplets, significant deuteration of CH4 and its H2 progeny was observed. Since the only source of deuterium identifiable was water from sulfuric acid, we have concluded that we should correct the HDO/H2O ratio in Venus water from 3.2 x 10(exp -2) to (5 plus or minus 0.7) x 10(exp -2). When the probe was in the lower atmosphere, transfer of deuterium from Venus HDO and HD to CH4 can account quantitatively for the deficiencies recorded in HDO and HD below 10 km, and consequently, the mysterious gradients in water vapor and hydrogen mixing ratios we have reported. The revision in the D/H ratio reduces the mixing ratio of water vapor (and H2) reported previously by a factor of 3.2/5. We are not yet able to say whether the methane detected was atmospheric or an instrumental artifact. If it was atmospheric, its release must have been episodic and highly localized. Otherwise, the large D/H ratio in Venus water and hydrogen could not be maintained

Analysis of OGO-6 observations of the 0 I 5577A tropical nightglow

Atomic oxygen green line data from the horizon scanning photometer on OGO-6 was examined. Unfolding the satellite data from the tropical F-region yields altitude and latitude variations of the O(1S) emissions. The spatial variations of the tropical F-region electron density are then calculated by assuming dissociative recombination and using a model atmosphere. Where comparisons to ground-based data are possible the results are good. Thus, the satellite observations constitute a form of topside sounding of the ionosphere below the F-peak and provide synoptic data about this portion of the ionsphere otherwise impractical to obtain

Detecting Star Formation in Brightest Cluster Galaxies with GALEX

We present the results of GALEX observations of 17 cool core (CC) clusters of galaxies. We show that GALEX is easily capable of detecting star formation in brightest cluster galaxies (BCGs) out to $z\ge 0.45$ and 50-100 kpc. In most of the CC clusters studied, we find significant UV luminosity excesses and colors that strongly suggest recent and/or current star formation. The BCGs are found to have blue UV colors in the center that become increasingly redder with radius, indicating that the UV signature of star formation is most easily detected in the central regions. Our findings show good agreement between UV star formation rates and estimates based on H$\alpha$ observations. IR observations coupled with our data indicate moderate-to-high dust attenuation. Comparisons between our UV results and the X-ray properties of our sample suggest clear correlations between UV excess, cluster entropy, and central cooling time, confirming that the star formation is directly and incontrovertibly related to the cooling gas.Comment: 39 pages, 11 figures; accepted for publication in The Astrophysical Journal. Figure quality reduced to comply with arXiv file size requirement

Mitigating Differential Power Analysis Attacks on AES using NeuroMemristive Hardware

Cryptographic algorithms such as the Advanced Encryption Standard (AES) are vulnerable to side channel attacks. AES was once thought to be impervious to attacks, but this proved to be true only for a mathematical model of AES, not a physical realization. Hard- ware implementations leak side channel information such as power dissipation. One of the practical SCA attacks is the Differential power analysis (DPA) attack, which statistically analyzes power measurements to find data-dependent correlations. Several countermeasures against DPA have been proposed at the circuit and logic level in conventional technologies. These techniques generally include masking the data inside the algorithm or hiding the power profile. Next generation processors bring in additional challenges to mitigate DPA attacks, by way of heterogeneity of the devices used in the hardware realizations. Neuromemristive systems hold potential in this domain and also bring new challenges to the hardware security of cryptosystems. In this exploratory work, a neuromemristive architecture was designed to compute an AES transformation and mitigate DPA attacks. The random power profile of the neuromemristive architecture reduces the correlations between data and power consumption. Hardware primitives, such as neuron and synapse circuits were developed along with a framework to generate neural networks in hardware. An attack framework was developed to run DPA attacks using different leakage models. A baseline AES cryptoprocessor using only CMOS technology was attacked successfully. The SubBytes transformation was replaced by a neuromemristive architecture, and the proposed designs were more resilient against DPA attacks at the cost of increased power consumption

Exploring notions of genre in 'academic literacies' and 'writing across the curriculum': approaches across countries and contexts

The SIGET IV panel on genre in Writing Across the Curriculum (WAC) and “academic literacies” (ACLITS) has set rolling a discussion of the similarities and differences in the two traditions, the former originating in the US in the early 1970s, the latter originating in England in the early 1990s. This paper maps out some elements of each in relation to the other and to genre, which we hope will set in motion further discussions and cross-fertilization

The mass-L_x relation for moderate luminosity X-ray clusters

We present measurements of the masses of a sample of 25 moderate X-ray luminosity clusters of galaxies from the 160 square degree ROSAT survey. The masses were obtained from a weak lensing analysis of deep F814W images obtained using the Advanced Camera for Surveys (ACS). We present an accurate empirical correction for the effect of charge transfer (in)efficiency on the shapes of faint galaxies. A significant lensing signal is detected around most of the clusters. The lensing mass correlates tightly with the cluster richness. We measured the intrinsic scatter in the scaling relation between M_2500 and L_X and find the best fit power law slope and normalisation to be alpha=0.68+-0.07 and M_X=(1.2+-0.12)10^14M_sun (for L_X=2x10^44 erg/s). These results agree well with a number of recent studies, but the normalisation is lower compared to the study of Rykoff et al. (2008b). One explanation for this difference may be the fact that (sub)structures projected along the line-of-sight boost both the galaxy counts and the lensing mass. Such superpositions lead to an increased mass at a given L_X when clusters are binned by richness.Comment: accepted for publication in the Astrophysical Journal; 15 pages, 11 figure

Pancreatic cancer patient survival correlates with DNA methylation of pancreas development genes.

DNA methylation is an epigenetic mark associated with regulation of transcription and genome structure. These markers have been investigated in a variety of cancer settings for their utility in differentiating normal tissue from tumor tissue. Here, we examine the direct correlation between DNA methylation and patient survival. We find that changes in the DNA methylation of key pancreatic developmental genes are strongly associated with patient survival

Development in helicopter tail boom strake applications in the US

The use of a strake or spoiler on a helicopter tail boom to beneficially change helicopter tail boom air loads was suggested in the United States in 1975. The anticipated benefits were a change of tail boom loads to reduce required tail rotor thrust and power and improve directional control. High tail boom air loads experienced by the YAH-64 and described in 1978 led to a wind tunnel investigation of the usefullness of strakes in altering such loads on the AH-64, UH-60, and UH-1 helicopters. The wind tunnel tests of 2-D cross sections of the tail boom of each demonstrated that a strake or strakes would be effective. Several limited test programs with the U.S. Army's OH-58A, AH-64, and UH-60A were conducted which showed the effects of strakes were modest for those helicopters. The most recent flight test program, with a Bell 204B, disclosed that for the 204B the tail boom strake or strakes would provide more than a modest improvement in directional control and reduction in tail rotor power