Final Report on Humidification-Dehumidification Desalination Prototype

Freshwater available across the globe is decreasing daily due to population growth, climate change, and pollution. The growing scarcity of freshwater affects more than a billion people worldwide and has prompted increased research into desalination processes. Large desalination plants are already in operation but are very expensive to build. Not every community has the means to implement these large systems, advancing the need for smaller, more economical, and efficient desalination plants. The Desalinators researched and designed a humidification-dehumidification (HDH) desalination prototype that will convert saline water into potable water at a household scale (approximately 5-10 gal/day of freshwater). The sponsor, SwRI, intends to use the results of this project to further their research into the applications and improvements of small-scale HDH processes. Therefore, the prototype need not be perfect as long as it produces results that can be measured and analyzed. The prototype features four main subsystems: primary heater, air circulation system, humidifier, and condenser. After the team’s extensive research, the final prototype was built using a water heater provided by the sponsor, an air pump (for forced convection) provided by the University, a packed bed tower humidifier with Raschig rings, and an ice bath within a plastic bucket with an air separator for the condenser. A schematic of the final prototype can be found in the figure section of the appendix. The team chose these components to maximize the performance of the prototype while minimizing costs. The six project requirements included the following: the prototype shall use the HDH process to desalinate saline water into potable water; the prototype should operate within ±20% error of design parameters, including operating temperature, humidity at inlet and outlet, and outlet salt content; the prototype shall allow the operating temperature, humidity at inlet and outlet, and outlet salt content to be measured; the prototype should allow efficiency to be measured and compared to current desalination processes via gained-output ratio (GOR), recovery ratio (RR), or other efficiency measures; the prototype should allow outlet water samples to be collected and tested by instruments provided by SwRI; and the prototype may produce between 5-10 gallons/day. To meet these requirements, several “complete prototype tests” were conducted in which temperatures, flow rates, humidity, and salinities were measured at 3-minute intervals during a 21-30 minute test. The complete prototype tests were conducted at a variety of water heater setpoints and flow rates. An additional “long test” was conducted as well where the same values were measured but for 100 minutes at 4-minute intervals. Using the results of these tests, the team was able to show that the prototype successfully met all but the last project requirement regarding potable water output volume and selecting optimal operating conditions. The potable water volume production rate could be increased if the tubing used within the prototype was upgraded to better withstand moderate pressures as well as using larger water and air pumps to increase flow rates

Alcohol: taking a population perspective

Alcohol consumption is a global phenomenon, as is the resultant health, social and economic harm. The nature of these harms varies with different drinking patterns and with the societal and political responses to the burden of harm; nevertheless, alcohol-related chronic diseases have a major effect on health. Strong evidence exists for the effectiveness of different strategies to minimize this damage and those policies that target price, availability and marketing of alcohol come out best, whereas those using education and information are much less effective. However, these policies can be portrayed as anti-libertarian and so viewing them in the context of alcohol-related harm to those other than the drinker, such as the most vulnerable in society, is important. When this strategy is successful, as in Scotland, it has been possible to pass strong and effective legislation, such as for a minimum unit price for alcohol

Alcohol brand use of youth-appealing advertising and consumption by youth and adults

Background: Youth exposure to alcohol marketing has been shown to be an important contributor to the problem of underage drinking in the U.S. More work is needed on identifying and minimizing content with particular appeal to youth. Design and Methods: We tested the association between the youth-appeal of marketing content of televised alcohol advertisements and the brand-specific alcohol consumption of both underage youth and adults. We used existing data from three sources: a brand-specific alcohol consumption survey among underage youth (N=1032), a brand-specific alcohol consumption survey among adults (N ~13,000), and an analysis of content appealing to youth (CAY) in a sample of televised alcohol advertisements (n=96) aired during the youth survey. The association between CAY scores for the 96 alcohol ads and youth (age 13-20) versus adult (age 21+) consumption of those ads’ brands was tested through bivariate and multivariate models. Results: Brand CAY scores were (a) positively associated with brand-specific youth consumption after controlling for adult brand consumption; (b) positively associated with a ratio of youth-toadult brand-specific consumption; and (c) not associated with adult brand consumption. Conclusions: Alcohol brands with youth-appealing advertising are consumed more often by youth than adults, indicating that these ads may be more persuasive to relatively younger audiences, and that youth are not simply mirroring adult consumption patterns in their choice of brands. Future research should consider the content of alcohol advertising when testing marketing effects on youth drinking, and surveillance efforts might focus on brands popular among youth

Microstructural asymmetry of the corticospinal tracts predicts right-left differences in circle drawing skill in right-handed adolescents

Most humans show a strong preference to use their right hand, but strong preference for the right hand does not necessarily imply a strong right–left asymmetry in manual proficiency (i.e., dexterity). Here we tested the hypothesis that intra-individual asymmetry of manual proficiency would be reflected in microstructural differences between the right and left corticospinal tract (CST) in a cohort of 52 right-handed typically-developing adolescents (11–16 years). Participants were asked to fluently draw superimposed circles with their right dominant and left non-dominant hand. Temporal regularity of circle drawing movements was assessed for each hand using a digitizing tablet. Although all participants were right-handed, there was substantial inter-individual variation regarding the relative right-hand advantage for fluent circle drawing. All subjects underwent whole-brain diffusion tensor imaging at 3 Tesla. The right and left CST were defined as regions-of-interest and mean fractional anisotropy (FA) and diffusivity values were calculated for right and left CST. On average, mean FA values were higher in the left CST relative to right CST. The degree of right–left FA asymmetry showed a linear relationship with right–left asymmetry in fluent circle drawing after correction for age and gender. The higher the mean FA values were in the left dominant CST relative to the right non-dominant CST, the stronger was the relative right-hand advantage for regular circle drawing. These findings show that right–left differences in manual proficiency are highly variable in right-handed adolescents and that this variation is associated with a right-left microstructural asymmetry of the CST

GenderMag: A Method for Evaluating Software’s Gender Inclusiveness

In recent years, research into gender differences has established that individual differences in how people problem-solve often cluster by gender. Research also shows that these differences have direct implications for software that aims to support users’ problem-solving activities, and that much of this software is more supportive of problem-solving processes favored (statistically) more by males than by females. However, there is almost no work considering how software practitioners—such as User Experience (UX) professionals or software developers—can find gender-inclusiveness issues like these in their software. To address this gap, we devised the GenderMag method for evaluating problem-solving software from a gender-inclusiveness perspective. The method includes a set of faceted personas that bring five facets of gender difference research to life, and embeds use of the personas into a concrete process through a gender-specialized Cognitive Walkthrough. Our empirical results show that a variety of practitioners who design software—without needing any background in gender research—were able to use the GenderMag method to find gender-inclusiveness issues in problem-solving software. Our results also show that the issues the practitioners found were real and fixable. This work is the first systematic method to find gender-inclusiveness issues in software, so that practitioners can design and produce problem-solving software that is more usable by everyone