A Review of Sample Analysis at Mars-Evolved Gas Analysis Laboratory Analog Work Supporting the Presence of Perchlorates and Chlorates in Gale Crater, Mars

The Sample Analysis at Mars (SAM) instrument on the Curiosity rover has detected evidence of oxychlorine compounds (i.e., perchlorates and chlorates) in Gale crater, which has implications for past habitability, diagenesis, aqueous processes, interpretation of in situ organic analyses, understanding the martian chlorine cycle, and hazards and resources for future human exploration. Pure oxychlorines and mixtures of oxychlorines with Mars-analog phases have been analyzed for their oxygen (O2) and hydrogen chloride (HCl) releases on SAM laboratory analog instruments in order to constrain which phases are present in Gale crater. These studies demonstrated that oxychlorines evolve O2 releases with peaks between ~200 and 600 °C, although the thermal decomposition temperatures and the amount of evolved O2 decrease when iron phases are present in the sample. Mg and Fe oxychlorines decompose into oxides and release HCl between ~200 and 542 °C. Ca, Na, and K oxychlorines thermally decompose into chlorides and do not evolve HCl by themselves. However, the chlorides (original or from oxychlorine decomposition) can react with water-evolving phases (e.g., phyllosilicates) in the sample and evolve HCl within the temperature range of SAM (<~870 °C). These laboratory analog studies support that the SAM detection of oxychlorine phases is consistent with the presence of Mg, Ca, Na, and K perchlorate and/or chlorate along with possible contributions from adsorbed oxychlorines in Gale crater samples.

How many modes does it take to describe climate change?: The lessons from an experiment

&lt;p&gt;According to everyone's experience, predicting the weather reliably for more than 8 days seems an impossible task for our best weather agencies. At the same time, politicians and citizens are asking scientists for decades of climate predictions to help them make decisions, especially on CO2 emissions. To what extent is this request scientifically admissible?&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;&lt;p&gt;In this lecture I will investigate this question, focusing on the topic of predictions of bifurcations of the atmospheric or oceanic circulations. In such case, the issue is whether present climate models, that have necessarily a finite resolution and a smaller number of degrees of freedom than the actual terrestrial systems, are able to reproduce spontaneous or forced bifurcations. For this, I will use recent results obtained by my group in a laboratory analog of such systems, so called von Karman flow, in which spontaneous bifurcations of the circulation take place. I will detail the analogy, and investigate the nature of bifurcations, the number of degrees of freedom that characterizes it and discuss what is the effect of reducing the number of degrees of freedom in such system.&lt;/p&gt;&lt;p&gt;I will also discuss the role of fluctuations and their origin, and stress the importance of describing very small scales to capture fluctuations of correct intensity and scale.&lt;/p&gt;

The role of horizontal rolls in rapid intensification of cyclonic vortex

&lt;p&gt;The present laboratory study is focused on the role of convective rolls in enhancement of the heat flux from the sea and triggering of the process of rapid intensification of tropical cyclones. The appearance of coherent convective structures such as thermals and rolls are registered by different optical techniques and temperature measurements. Two-dimensional velocity fields are used for the study of the structure and characteristics of the flow. The heat flux from the heating plate to the fluid is measured directly. Obtained results clearly show that rapid intensification of a laboratory analog of a tropical cyclone is tightly linked with the heat transfer process in the boundary layer. Formation of secondary convective structures strongly increases the heat transfer and intensity of convective circulation. Intensity of radial inflow is a crucial aspect for the intensification of cyclonic vortex, hence rapid variation of the heat transfer is a factor that has a substantial influence on the dynamics of a laboratory vortex. &lt;/p&gt;

Further Validation of a Laboratory Analog Sexual Aggression Task: Associations With Novel Risk Factors for Sexual Violence

Official crime statistics and self-reports of sexual aggression perpetration are limited by various factors (e.g., lack of reporting, social desirability bias), as well as an inability to use these measures in experimental studies of sexual aggression. To address these issues, Nagayama Hall et al. (1994) developed a laboratory analog measure of sexual aggression, which has received empirical support as a valid measure of sexual aggression proclivity. Here, we seek to replicate these findings and further validate the paradigm by examining sexually aggressive responses in relation to a range of recently emerging predictors of sexual aggression (e.g., sexual objectification, sexual narcissism) as well as participants’ perceptions of a female confederate serving as the target of sexual aggression. A sample of 49 undergraduate men completed questionnaires and participated in the sexual aggression analog task. Results of logistic regression analyses supported both criterion and construct validity of the analog task; men who chose the sexually explicit video were more likely to report prior sexual aggression, greater sexual objectification of women, higher sexual narcissism, greater hostile sexism, and higher impersonal dating. These men were also more likely to express dehumanizing beliefs about the female confederate, consider her less intelligent, and believe she was more distressed by the video. These results replicate and extend prior research supporting this paradigm as a valid laboratory-based measure of sexual aggression proclivity that can be used in tandem with validated self-report measures.