Chandra Observations of the Optically Dark GRB030528

The X-ray-rich GRB030528 was detected by the HETE satellite and its localization was rapidly disseminated. However, early optical observations failed to detect a counterpart source. In a 2-epoch ToO observation with Chandra, we discovered a fading X-ray source likely counterpart to GRB030528. The source brightness was typical of X-ray afterglows observed at similar epochs. Other observers detected an IR source at a location consistent with the X-ray source. The X-ray spectrum is not consistent with a large absorbing column.Comment: 4 pages, 1 figures, to appear in Santa Fe GRB Conference Proceedings, 200

Previously Claimed(/Unclaimed) X-ray Emission Lines in High Resolution Afterglow Spectra

We review the significance determination for emission lines in the Chandra HETGS spectrum for GRB020813, and we report on a search for additional lines in high resolution Chandra spectra. No previously unclaimed features are found. We also discuss the significance of lines sets reportedly discovered using XMM data for GRB011211 and GRB030227. We find that these features are likely of modest, though not negligible, significance.Comment: 4 pages, 1 figures, to appear in Santa Fe GRB Conference Proceedings, 200

Optical and X-ray Observations of the Afterglow to XRF030723

The X-ray-flash XRF030723 was detected by the HETE satellite and rapidly disseminated, allowing for an optical transient to be detected ~1 day after the burst. We discuss observations in the optical with Magellan, which confirmed the fade of the optical transient. In a 2-epoch ToO observation with Chandra, we discovered a fading X-ray source spatially coincident with the optical transient. We present spectral fits to the X-ray data. We also discuss the possibility that the source underwent a rebrightening in the X-rays, as was observed in the optical. We find that the significance of a possible rebrightening is very low (~1 sigma).Comment: 4 pages, 2 figures, to appear in Santa Fe GRB Conference Proceedings, 200

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

Seasonal changes in brain serotonin transporter binding in short 5-HTTLPR-allele carriers but not in long-allele homozygotes

Several findings suggest seasonal variations in the serotonin (5-HT) system. We sought evidence for seasonal variation in the serotonin transporter (5-HTT). We found that length of daylight time in minutes correlates negatively with 5-HTT binding in the putamen and the caudate, with a similar tendency in the thalamus, but no such association in the midbrain. In the putamen, an anatomical region with a dense serotonin innervation that is implicated in processing of aversive stimuli, we found a significant gene*daylight effect with a negative correlation between the 5-HTT binding and daylight time in carriers of the short 5-HTTLPR allele, but not in carriers of the long allele. The neurobiological endophenotype identified here directly links activation studies, showing responses on the neural circuit level, with dynamic changes in transporter expression measured in vivo

The importance of chemosensory clues in Aguaruna tree classification and identification

<p>Abstract</p> <p>Background</p> <p>The ethnobotanical literature still contains few detailed descriptions of the sensory criteria people use for judging membership in taxonomic categories. Olfactory criteria in particular have been explored very little. This paper will describe the importance of odor for woody plant taxonomy and identification among the Aguaruna Jívaro of the northern Peruvian Amazon, focusing on the Aguaruna category <b><it>númi </it></b>(trees excluding palms). Aguaruna informants almost always place trees that they consider to have a similar odor together as <b><it>kumpají </it></b>– 'companions,' a metaphor they use to describe trees that they consider to be related.</p> <p>Methods</p> <p>The research took place in several Aguaruna communities in the upper Marañón region of the Peruvian Amazon. Structured interview data focus on informant criteria for membership in various folk taxa of trees. Informants were also asked to explain what members of each group of related companions had in common. This paper focuses on odor and taste criteria that came to light during these structured interviews. Botanical voucher specimens were collected, wherever possible.</p> <p>Results</p> <p>Of the 182 tree folk genera recorded in this study, 51 (28%) were widely considered to possess a distinctive odor. Thirty nine of those (76%) were said to have odors similar to some other tree, while the other 24% had unique odors. Aguaruna informants very rarely described tree odors in non-botanical terms. Taste was used mostly to describe trees with edible fruits. Trees judged to be related were nearly always in the same botanical family.</p> <p>Conclusion</p> <p>The results of this study illustrate that odor of bark, sap, flowers, fruit and leaves are important clues that help the Aguaruna to judge the relatedness of trees found in their local environment. In contrast, taste appears to play a more limited role. The results suggest a more general ethnobotanical hypothesis that could be tested in other cultural settings: people tend to consider plants with similar odors to be related, but say that plants with unique odors are unrelated to any other plants.</p

Meaningful associations in the adolescent brain cognitive development study

The Adolescent Brain Cognitive Development (ABCD) Study is the largest single-cohort prospective longitudinal study of neurodevelopment and children\u27s health in the United States. A cohort of n = 11,880 children aged 9-10 years (and their parents/guardians) were recruited across 22 sites and are being followed with in-person visits on an annual basis for at least 10 years. The study approximates the US population on several key sociodemographic variables, including sex, race, ethnicity, household income, and parental education. Data collected include assessments of health, mental health, substance use, culture and environment and neurocognition, as well as geocoded exposures, structural and functional magnetic resonance imaging (MRI), and whole-genome genotyping. Here, we describe the ABCD Study aims and design, as well as issues surrounding estimation of meaningful associations using its data, including population inferences, hypothesis testing, power and precision, control of covariates, interpretation of associations, and recommended best practices for reproducible research, analytical procedures and reporting of results