Dating, dining, and ducks: Monitoring the recovery of campus lakes after dredging

Dr. Emily Kane, Assistant Professor, Department of Biology ($30,000.00) Monitored pond recovery after recent dredging by involving students to survey these ponds each month for 1 year. Results were shared in hopes of promoting an understanding of campus biodiversity, the ecology of these ponds, and the importance of sustainable activities

Prototype laser-diode-pumped solid state laser transmitters

Monolithic, diode-pumped Nd:YAG ring lasers can provide diffraction-limited, single-frequency, narrow-linewidth, tunable output which is adequate for use as a local oscillator in a coherent communication system. A laser was built which had a linewidth of about 2 kHz, a power of 5 milliwatts, and which was tunable over a range of 30 MHz in a few microseconds. This laser was phase-locked to a second, similar laser. This demonstrates that the powerful technique of heterodyne detection is possible with a diode-pumped laser used as the local oscillator. Laser diode pumping of monolithic Nd:YAG rings can lead to output powers of hundreds of milliwatts from a single laser. A laser was built with a single-mode output of 310 mW. Several lasers can be chained together to sum their power, while maintaining diffraction-limited, single frequency operation. This technique was demonstrated with two lasers, with a total output of 340 mW, and is expected to be practical for up to about ten lasers. Thus with lasers of 310 mW, output of up to 3 W is possible. The chaining technique, if properly engineered, results in redundancy. The technique of resonant external modulation and doubling is designed to efficiently convert the continuous wave, infrared output of our lasers into low duty-cycle pulsed green output. This technique was verified through both computer modeling and experimentation. Further work would be necessary to develop a deliverable system using this technique

Dating, dining, and ducks: Continued recovery of campus lakes after dredging

Proposed by Hannah Cohen, GS Student, and Drs. Emily Kane and Christian Cox , Department of Biology. ($19,000.00

Behavioral Performance and Evolution of Feeding Modes in Odontocetes

Vertebrate evolution has resulted in a diversity of feeding mechanisms. Cetaceans are secondarily derived tetrapods that have returned to a marine habitat. As a result, they display feeding modes that have converged with more basal aquatic vertebrates, but display a diversity of new solutions and adaptations. To begin to explore the diversity of feeding adaptations among odontocetes, kinematics of feeding modes and feeding adaptations for belugas (Delphinapterus leucas), Pacific white-sided dolphins (Lagenorhynchus obliquidens), and long-finned pilot whales (Globicephala melas) were characterized. In addition, direct measurements of intraoral pressure were collected to determine maximum suction performance. Characters from these analyses were combined with data for other odontocetes, and were mapped onto a phylogeny of Odontoceti to begin to explore where changes in feeding modes took place. Feeding modes were diverse in belugas, Pacific white-sided dolphins, and pilot whales and included suction, ram, and a combination of both. In general, four phases were observed: (I) preparatory, (II) jaw opening, (III) gular depression, and (IV) jaw closing. Suction was a large component of the prey capture method in belugas and subambient pressures in excess of 100 kPa were generated. Belugas were also capable of lateral lip gape occlusion and anterior lip pursing to form a small anterior aperture. Pacific whitesided dolphins relied on ram to capture prey. However, some degree of pursing and resultant subambient pressure was observed that was likely used to compensate for high ram speeds or for prey manipulation and transport to the esophagus. Pilot whales were more similar to belugas in kinematics, but maintained high approach velocities and did not generate significant suction pressures; suction and ram were used in combination. Belugas and pilot whales appeared to employ hyolingual depression as a primary suction generation mechanism, whereas Pacific white-sided dolphins relied on fast jaw opening. Ancestral state reconstructions indicated that suction feeding capability evolved independently at least six times within Odontoceti. These results indicate the diversity of feeding behaviors in odontocetes and provide directives for future studies on the diversity of feeding in secondarily aquatic mammals

Maternal-to-fetal allopurinol transfer and xanthine oxidase suppression in the late gestation pregnant rat.

Fetal brain hypoxic injury remains a concern in high-risk delivery. There is significant clinical interest in agents that may diminish neuronal damage during birth asphyxia, such as in allopurinol, an inhibitor of the prooxidant enzyme xanthine oxidase. Here, we established in a rodent model the capacity of allopurinol to be taken up by the mother, cross the placenta, rise to therapeutic levels, and suppress xanthine oxidase activity in the fetus. On day 20 of pregnancy, Wistar dams were given 30 or 100 mg kg(-1) allopurinol orally. Maternal and fetal plasma allopurinol and oxypurinol concentrations were measured, and xanthine oxidase activity in the placenta and maternal and fetal tissues determined. There were significant strong positive correlations between maternal and fetal plasma allopurinol (r = 0.97, P < 0.05) and oxypurinol (r = 0.88, P < 0.05) levels. Under baseline conditions, maternal heart (2.18 ± 0.62 mU mg(-1)), maternal liver (0.29 ± 0.08 mU mg(-1)), placenta (1.36 ± 0.42 mU mg(-1)), fetal heart (1.64 ± 0.59 mU mg(-1)), and fetal liver (0.14 ± 0.08 mU mg(-1)) samples all showed significant xanthine oxidase activity. This activity was suppressed in all tissues 2 h after allopurinol administration and remained suppressed 24 h later (P < 0.05), despite allopurinol and oxypurinol levels returning toward baseline. The data establish a mammalian model of xanthine oxidase inhibition in the mother, placenta, and fetus, allowing investigation of the role of xanthine oxidase-derived reactive oxygen species in the maternal, placental, and fetal physiology during healthy and complicated pregnancy

CrossCheck:toward passive sensing and detection of mental health changes in people with schizophrenia

Early detection of mental health changes in individuals with serious mental illness is critical for effective intervention. CrossCheck is the first step towards the passive monitoring of mental health indicators in patients with schizophrenia and paves the way towards relapse prediction and early intervention. In this paper, we present initial results from an ongoing randomized control trial, where passive smartphone sensor data is collected from 21 outpatients with schizophrenia recently discharged from hospital over a period ranging from 2-8.5 months. Our results indicate that there are statistically significant associations between automatically tracked behavioral features related to sleep, mobility, conversations, smartphone usage and self-reported indicators of mental health in schizophrenia. Using these features we build inference models capable of accurately predicting aggregated scores of mental health indicators in schizophrenia with a mean error of 7.6% of the score range. Finally, we discuss results on the level of personalization that is needed to account for the known variations within people. We show that by leveraging knowledge from a population with schizophrenia, it is possible to train accurate personalized models that require fewer individual-specific data to quickly adapt to new user

Developmental programming of cardiovascular dysfunction by prenatal hypoxia and oxidative stress.

Fetal hypoxia is a common complication of pregnancy. It has been shown to programme cardiac and endothelial dysfunction in the offspring in adult life. However, the mechanisms via which this occurs remain elusive, precluding the identification of potential therapy. Using an integrative approach at the isolated organ, cellular and molecular levels, we tested the hypothesis that oxidative stress in the fetal heart and vasculature underlies the molecular basis via which prenatal hypoxia programmes cardiovascular dysfunction in later life. In a longitudinal study, the effects of maternal treatment of hypoxic (13% O(2)) pregnancy with an antioxidant on the cardiovascular system of the offspring at the end of gestation and at adulthood were studied. On day 6 of pregnancy, rats (n = 20 per group) were exposed to normoxia or hypoxia ± vitamin C. At gestational day 20, tissues were collected from 1 male fetus per litter per group (n = 10). The remaining 10 litters per group were allowed to deliver. At 4 months, tissues from 1 male adult offspring per litter per group were either perfusion fixed, frozen, or dissected for isolated organ preparations. In the fetus, hypoxic pregnancy promoted aortic thickening with enhanced nitrotyrosine staining and an increase in cardiac HSP70 expression. By adulthood, offspring of hypoxic pregnancy had markedly impaired NO-dependent relaxation in femoral resistance arteries, and increased myocardial contractility with sympathetic dominance. Maternal vitamin C prevented these effects in fetal and adult offspring of hypoxic pregnancy. The data offer insight to mechanism and thereby possible targets for intervention against developmental origins of cardiac and peripheral vascular dysfunction in offspring of risky pregnancy

Adults and Children in Low-Income Households That Participate in Cost-Offset Community Supported Agriculture Have High Fruit and Vegetable Consumption

This paper examines fruit and vegetable intake (FVI) in low-income households that participated in a cost-offset (CO), or 50% subsidized, community-supported agriculture (CSA) program. CSA customers paid farms upfront for a share of the harvest, and received produce weekly throughout the growing season. A cohort of adults and children 2–12 y in a summer CO-CSA were surveyed online twice: August 2015 (n = 41) and February 2016 (n = 23). FVI was measured by the National Cancer Institute’s (NCI) Fruit and Vegetable Screener (FVS) and an inventory of locally grown fruits and vegetables. FVI relative to United States (US) recommendations and averages, and across seasons, were tested with non-parametric tests and paired t-tests (p < 0.05). Both adults and children in the CO-CSA had higher FVI than the US averages, and more often met recommendations for vegetables. Some summer fruits and vegetables were more often eaten when locally in-season. The CO-CSA model warrants further examination as an avenue for improving vegetable consumption among adults and children in low-income households. However, causality between CO-CSA participation and FVI cannot be inferred, as CO-CSA participants may be positive deviants with respect to FVI. A multi-state randomized controlled trial is currently underway to evaluate impacts of CO-CSAs on FVI and related outcomes

Validating AU Microscopii d with Transit Timing Variations

AU Mic is a young (22 Myr), nearby exoplanetary system that exhibits excess transit timing variations (TTVs) that cannot be accounted for by the two known transiting planets nor stellar activity. We present the statistical “validation” of the tentative planet AU Mic d (even though there are examples of “confirmed” planets with ambiguous orbital periods). We add 18 new transits and nine midpoint times in an updated TTV analysis to prior work. We perform the joint modeling of transit light curves using EXOFASTv2 and extract the transit midpoint times. Next, we construct an O − C diagram and use Exo-Striker to model the TTVs. We generate TTV log-likelihood periodograms to explore possible solutions for d’s period, then follow those up with detailed TTV and radial velocity Markov Chain Monte Carlo modeling and stability tests. We find several candidate periods for AU Mic d, all of which are near resonances with AU Mic b and c of varying order. Based on our model comparisons, the most-favored orbital period of AU Mic d is 12.73596 ± 0.00793 days ( T _C _,d = 2458340.55781 ± 0.11641 BJD), which puts the three planets near 4:6:9 mean-motion resonance. The mass for d is 1.053 ± 0.511 M _⊕ , making this planet Earth-like in mass. If confirmed, AU Mic d would be the first known Earth-mass planet orbiting a young star and would provide a valuable opportunity in probing a young terrestrial planet’s atmosphere. Additional TTV observations of the AU Mic system are needed to further constrain the planetary masses, search for possible transits of AU Mic d, and detect possible additional planets beyond AU Mic c