The Myth of Superiority of American Encryption Products

Encryption software and hardware use sophisticated mathematical algorithms to encipher a message so that only the intended recipient may read it. Fearing that criminals and terrorists will use encryption to evade authorities, the United States now restricts the export of encryption products with key lengths of more than 56 bits. The controls are futile, because strong encryption products are readily available overseas. Foreign-made encryption products are as good as, or better than, U.S.-made products. U.S. cryptographers have no monopoly on the mathematical knowledge and methods used to create strong encryption. Powerful encryption symmetric-key technologies developed in other countries include IDEA and GOST. Researchers in New Zealand have developed very strong public-key encryption systems. As patents on strong algorithms of U.S. origin expire, researchers in other countries will gain additional opportunities to develop strong encryption technology based on those algorithms

Homelessness and Money Mismanagement in Iraq and Afghanistan Veterans

Objectives. We examined the empirical link between money mismanagement and subsequent homelessness among veterans

Recommendations for myasthenia gravis clinical trials

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Gas Accretion and Galactic Chemical Evolution: Theory and Observations

This chapter reviews how galactic inflows influence galaxy metallicity. The goal is to discuss predictions from theoretical models, but particular emphasis is placed on the insights that result from using models to interpret observations. Even as the classical G-dwarf problem endures in the latest round of observational confirmation, a rich and tantalizing new phenomenology of relationships between $M_*$, $Z$, SFR, and gas fraction is emerging both in observations and in theoretical models. A consensus interpretation is emerging in which star-forming galaxies do most of their growing in a quiescent way that balances gas inflows and gas processing, and metal dilution with enrichment. Models that explicitly invoke this idea via equilibrium conditions can be used to infer inflow rates from observations, while models that do not assume equilibrium growth tend to recover it self-consistently. Mergers are an overall subdominant mechanism for delivering fresh gas to galaxies, but they trigger radial flows of previously-accreted gas that flatten radial gas-phase metallicity gradients and temporarily suppress central metallicities. Radial gradients are generically expected to be steep at early times and then flattened by mergers and enriched inflows of recycled gas at late times. However, further theoretical work is required in order to understand how to interpret observations. Likewise, more observational work is needed in order to understand how metallicity gradients evolve to high redshifts.Comment: Invited review to appear in Gas Accretion onto Galaxies, Astrophysics and Space Science Library, eds. A. J. Fox & R. Dav\'e, to be published by Springer. 29 pages, 2 figure

Insights into hydroxyl measurements and atmospheric oxidation in a California forest

The understanding of oxidation in forest atmospheres is being challenged by measurements of unexpectedly large amounts of hydroxyl (OH). A significant number of these OH measurements were made by laser-induced fluorescence in low-pressure detection chambers (called Fluorescence Assay with Gas Expansion (FAGE)) using the Penn State Ground-based Tropospheric Hydrogen Oxides Sensor (GTHOS). We deployed a new chemical removal method to measure OH in parallel with the traditional FAGE method in a California forest. The new method gives on average only 40–60% of the OH from the traditional method and this discrepancy is temperature dependent. Evidence indicates that the new method measures atmospheric OH while the traditional method is affected by internally generated OH, possibly from oxidation of biogenic volatile organic compounds. The improved agreement between OH measured by this new technique and modeled OH suggests that oxidation chemistry in at least one forest atmosphere is better understood than previously thought

Australian Education Joins the OECD : Federalism, Regionalization, and the Role of Education in a Time of Transition

This chapter argues that Australian interactions with the Organisation for Economic Co-operation and Development (OECD) in the field of education in the mid- to late-1970s pointed in two separate but not yet incompatible directions—one equity-oriented and the other more in line with the standardization and accountability regime typically identified with the OECD’s current policies—both of which favored a shift of authority toward the national level in educational policy-making. In the process, the chapter highlights the importance of considering movements between different spatial levels of analysis when tracing the ability of international organizations to get their ideas and visions “out of house.” The chapter first outlines the international and domestic contexts for Australia’s early involvement in the OECD, followed by a discussion of the negotiations of state and federal interests on the Australian Commonwealth Department of Education’s advisory committee on OECD matters. This discussion, in turn, frames the last three analytical sections of the chapter, on interactions between the OECD and the Australian education authorities at different levels on initiatives negotiating both the location of authority between these levels and the role of education at a time when the relation between its social and economic potential was up for revision.Non peer reviewe

Missing peroxy radical sources within a summertime ponderosa pine forest

Organic peroxy (RO₂) and hydroperoxy (HO₂) radicals are key intermediates in the photochemical processes that generate ozone, secondary organic aerosol and reactive nitrogen reservoirs throughout the troposphere. In regions with ample biogenic hydrocarbons, the richness and complexity of peroxy radical chemistry presents a significant challenge to current-generation models, especially given the scarcity of measurements in such environments. We present peroxy radical observations acquired within a ponderosa pine forest during the summer 2010 Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H₂O, Organics and Nitrogen – Rocky Mountain Organic Carbon Study (BEACHON-ROCS). Total peroxy radical mixing ratios reach as high as 180 pptv (parts per trillion by volume) and are among the highest yet recorded. Using the comprehensive measurement suite to constrain a near-explicit 0-D box model, we investigate the sources, sinks and distribution of peroxy radicals below the forest canopy. The base chemical mechanism underestimates total peroxy radicals by as much as a factor of 3. Since primary reaction partners for peroxy radicals are either measured (NO) or underpredicted (HO₂ and RO₂, i.e., self-reaction), missing sources are the most likely explanation for this result. A close comparison of model output with observations reveals at least two distinct source signatures. The first missing source, characterized by a sharp midday maximum and a strong dependence on solar radiation, is consistent with photolytic production of HO₂. The diel profile of the second missing source peaks in the afternoon and suggests a process that generates RO₂ independently of sun-driven photochemistry, such as ozonolysis of reactive hydrocarbons. The maximum magnitudes of these missing sources (~120 and 50 pptv min⁻¹, respectively) are consistent with previous observations alluding to unexpectedly intense oxidation within forests. We conclude that a similar mechanism may underlie many such observations

Observations of glyoxal and formaldehyde as metrics for the anthropogenic impact on rural photochemistry

We present simultaneous fast, in-situ measurements of formaldehyde and glyoxal from two rural campaigns, BEARPEX 2009 and BEACHON-ROCS, both located in Pinus Ponderosa forests with emissions dominated by biogenic volatile organic compounds (VOCs). Despite considerable variability in the formaldehyde and glyoxal concentrations, the ratio of glyoxal to formaldehyde, R<sub>GF</sub>, displayed a very regular diurnal cycle over nearly 2 weeks of measurements. The only deviations in R<sub>GF</sub> were toward higher values and were the result of a biomass burning event during BEARPEX 2009 and very fresh anthropogenic influence during BEACHON-ROCS. Other rapid changes in glyoxal and formaldehyde concentrations have hardly any affect on R<sub>GF</sub> and could reflect transitions between low and high NO regimes. The trend of increased R<sub>GF</sub> from both anthropogenic reactive VOC mixtures and biomass burning compared to biogenic reactive VOC mixtures is robust due to the short timescales over which the observed changes in R<sub>GF</sub> occurred. Satellite retrievals, which suggest higher R<sub>GF</sub> for biogenic areas, are in contrast to our observed trends. It remains important to address this discrepancy, especially in view of the importance of satellite retrievals and in situ measurements for model comparison. In addition, we propose that R<sub>GF</sub> represents a useful metric for biogenic or anthropogenic reactive VOC mixtures and, in combination with absolute concentrations of glyoxal and formaldehyde, furthermore represents a useful metric for the extent of anthropogenic influence on overall reactive VOC processing via NO<sub>x</sub>. In particular, R<sub>GF</sub> yields information about not simply the VOCs dominating reactivity in an airmass, but the VOC processing itself that is directly coupled to ozone and secondary organic aerosol production

Missing Peroxy Radical Sources Within a Rural Forest Canopy

Organic peroxy (RO2) and hydroperoxy (HO2) radicals are key intermediates in the photochemical processes that generate ozone, secondary organic aerosol and reactive nitrogen reservoirs throughout the troposphere. In regions with ample biogenic hydrocarbons, the richness and complexity of peroxy radical chemistry presents a significant challenge to current-generation models, especially given the scarcity of measurements in such environments. We present peroxy radical observations acquired within a Ponderosa pine forest during the summer 2010 Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H2O, Organics and Nitrogen - Rocky Mountain Organic Carbon Study (BEACHON-ROCS). Total peroxy radical mixing ratios reach as high as 180 pptv and are among the highest yet recorded. Using the comprehensive measurement suite to constrain a near-explicit 0-D box model, we investigate the sources, sinks and distribution of peroxy radicals below the forest canopy. The base chemical mechanism underestimates total peroxy radicals by as much as a factor of 3. Since primary reaction partners for peroxy radicals are either measured (NO) or under-predicted (HO2 and RO2, i.e. self-reaction), missing sources are the most likely explanation for this result. A close comparison of model output with observations reveals at least two distinct source signatures. The first missing source, characterized by a sharp midday maximum and a strong dependence on solar radiation, is consistent with photolytic production of HO2. The diel profile of the second missing source peaks in the afternoon and suggests a process that generates RO2 independently of sun-driven photochemistry, such as ozonolysis of reactive hydrocarbons. The maximum magnitudes of these missing sources (approximately 120 and 50 pptv min1, respectively) are consistent with previous observations alluding to unexpectedly intense oxidation within forests. We conclude that a similar mechanism may underlie many such observations