Snap-off production of monodisperse droplets

We introduce a novel technique to produce monodisperse droplets through the snap-off mechanism. The methodology is simple, versatile, and requires no specialized or expensive components. The droplets produced have polydispersity <1% and can be as small as 2.5 $\mu$m radius. A convenient feature is that the droplet size is constant over a 100-fold change in flow rate, while at higher flows the droplet size can be continuously adjusted.Comment: to be published in Eur. Phys. J. E as a "Tips and Tricks" articl

Parenting interventions for ADHD: a systematic literature review and meta-analysis

Objective. To evaluate the evidence base relating to the effectiveness of parent-administered behavioral interventions for ADHD

Water Security in Refugee Host Communities: Syrian Refugees in Jordan

This thesis adapts a dynamic economic model of groundwater extraction to analyze the environmental impact of the Syrian refugee influx from 2013 onward on the Amman Wadi As-Sir aquifer in the northern region of Jordan. It then shows that, given model assumptions, agricultural producers in the Jordanian Highlands experience negative welfare effects as the resource is allocated away from producing sectors of the economy in order to provide for the refugee population. Finally, it discusses policy implications for increasing water security in Jordan, focusing on two fronts: long-term capacity and local capacity.Ope

An Educational Intervention to Increase Fruit and Vegetable Consumption in Parents of Obese and Overweight Children

The incidence and prevalence of overweight and obese children in the United States is a serious health concern since the complications of childhood obesity can have serious and long-term effects: cardiovascular disease, sleep apnea, type 2 diabetes, neurological disease, and pulmonary disease. Parental modeling and nutritional education focusing on the obese/overweight child’s parents has been shown as an effective strategy for improving nutritional outcomes of the recommended servings of fruits and vegetables in children from five to ten years of age. Outcomes of this study and targeted nutritional modeling included increasing vegetable and fruit consumption of the parent by at least one fruit and vegetable serving per day post-intervention through nutritional education. The project purpose was to measure the impact of a parent-focused nutritional educational intervention that increases fruit and vegetable consumption in the parents of obese and overweight children. While the study indirectly measured a nutrition education intervention aimed at children via their parents, no children were included in this project. Parents (N = 93) of obese/overweight children were provided nutritional and modeling education over three months. A participation rate of 14% (N = 13) was achieved. The majority of the parents were single African American mothers between 18 and 25 years old with one or two children living in the household, an average income less than $10,000 per year, and some college or technical education. This project used a pre-and post-test design to measure the effectiveness of a nutritional educational intervention. A descriptive analysis of the participants was computed. Differences in the pre-and post-test scores on the parental dietary modeling questionnaire and the food frequency questionnaire were analyzed. Results showed a significant increase in fruit and vegetable consumption (p \u3c .05). The majority of the increase was due to improved fruit consumption. There was also an increase in parental modeling awareness. Parents’ understanding of the importance of parental modeling had an impact on nutritional selection of their own fruit and vegetable intake

Stakeholder representation in park planning: localized place meanings at Grand Canyon

This research explores stakeholder representation in park [pre]planning at Grand Canyon National Park through an examination of place meanings from a lived experience perspective. Using a combination of photo-elicitation methods and semi-structured interviewing this research offers a novel form of representation among localized stakeholders to the backcountry at Grand Canyon and follows up on that by asking the participants about their experience with the research itself. It is found that stakeholders who participated in this process expressed a natural form of caring and sensed the same in others representation of the meanings associated with their important backcountry places. As a form of participatory action research, this research shows promise for improving stakeholder dialogue surrounding park planning through the productive inclusion of experiential, emotional knowledge

The Power of Closing Time: Using Library Occupancy Data to Inform Operational Changes

Objectives: To use hourly building occupancy data over the period of 2012-2014 to determine the effect of changes to library hours of operation on building occupancy near and in the hours leading up to closing time. Methods: Data were collected using an automated gate count system at the primary entrance to the library. The system tracked the occupancy of the building by comparing the number of entrances and exits hourly each day. Incremental changes to the library’s hours of operation occurred in the same time period for the years 2012-2014. This time period will be compared year-to-year. We will test whether changes in closing time have a significant effect on mean occupancy rates during each of the three hours leading up to closing. Based on a previous study which examined a smaller, six-week period between 2012-2014, we expect to find that as closing time is extended, building occupancy in the hours preceding closing time increases despite a decrease in occupancy at closing. Results: Mean occupancy during the hour before closing time did not change when closing time was extended from 9 PM to 10PM. When closing time was extended to 12 AM, mean occupancy during the hour before closing decreased. Mean occupancy during the hour ending at 9 PM increased when closing time was extended from 9 PM to 10 PM. Mean occupancy during the hour ending at 10 PM increased when closing time was extended from 10 PM to 12 AM. We plan to also include data from the ongoing Spring semester in the final results. Conclusions: Occupancy near closing decreased as closing time became later. While occupancy near closing decreased somewhat, occupancy earlier in the evening increased as library hours were extended. The benefits of increased library occupancy appear to justify sustaining extended operating hours

Pattern fluctuations in transitional plane Couette flow

In wide enough systems, plane Couette flow, the flow established between two parallel plates translating in opposite directions, displays alternatively turbulent and laminar oblique bands in a given range of Reynolds numbers R. We show that in periodic domains that contain a few bands, for given values of R and size, the orientation and the wavelength of this pattern can fluctuate in time. A procedure is defined to detect well-oriented episodes and to determine the statistics of their lifetimes. The latter turn out to be distributed according to exponentially decreasing laws. This statistics is interpreted in terms of an activated process described by a Langevin equation whose deterministic part is a standard Landau model for two interacting complex amplitudes whereas the noise arises from the turbulent background.Comment: 13 pages, 11 figures. Accepted for publication in Journal of statistical physic

Experimental X-ray Stress Analysis Procedures for Ultra High Strength Materials

X-ray stress analysis procedures for accurate measurement of elastic strain in high strength steel

An attacker-defender model for IP-based networks

The Internet Protocol (IP) has emerged as the dominant technology for determining how data is routed across the Internet. Because IP flows are defined essentially in terms of origin-destination (O-D) pairs, we represent IP traffic engineering as a multi-commodity flow problem in which each O-D pair is treated as a separate commodity. We account for the diversity in IP routing by modeling opposite extremes of traffic engineering: "naive" traffic engineering where the IP routes data between any two users using only the shortest path between them, and "best case" traffic engineering where IP has the flexibility to route data using multiple paths in the network regardless of their length. We develop linear programming formulations that identify the maximum data flow for an IP network that satisfies proportionality constraints for traffic demand for each case of traffic engineering, and we also determine the optimal interdiction of those flows that reduces that maximum flow in the worst possible way.http://archive.org/details/anttackerdefende109454288US Navy (USN) author.Approved for public release; distribution is unlimited