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The Minnesota Center for Twin and Family Research (MCTFR) comprises multiple longitudinal, community-representative investigations of twin and adoptive families that focus on psychological adjustment, personality, cognitive ability and brain function, with a special emphasis on substance use and related psychopathology. The MCTFR includes the Minnesota Twin Registry (MTR), a cohort of twins who have completed assessments in middle and older adulthood; the Minnesota Twin Family Study (MTFS) of twins assessed from childhood and adolescence into middle adulthood; the Enrichment Study (ES) of twins oversampled for high risk for substance-use disorders assessed from childhood into young adulthood; the Adolescent Brain (AdBrain) study, a neuroimaging study of adolescent twins; and the Siblings Interaction and Behavior Study (SIBS), a study of adoptive and nonadoptive families assessed from adolescence into young adulthood. Here we provide a brief overview of key features of these established studies and describe new MCTFR investigations that follow up and expand upon existing studies or recruit and assess new samples, including the MTR Study of Relationships, Personality, and Health (MTR-RPH); the Colorado-Minnesota (COMN) Marijuana Study; the Adolescent Brain Cognitive Development (ABCD) study; the Colorado Online Twins (CoTwins) study and the Children of Twins (CoT) study.
This is a copy of the slides presented at the meeting but not formally written up for the volume.
Engineered nanoparticulate systems are anticipated to lead to advances in understanding biological processes at the molecular level and progress in the development of diagnostic tools and innovative therapies. Nanoparticle based imaging agents such as fluorescent dye-doped silica nanoparticles, quantum dots, gold nanoparticles, etc. have overcome many of the limitations of conventional contrast agents (organic dyes) such as poor photostability, low quantum yield and insufficient in vitro and in vivo stability. Additionally, the development of multifunctional nanoparticles, which can be detected simultaneously by multiple techniques e.g. Magnetic Resonance Imaging (MRI) and Optical Imaging integrate the advantages of high sensitivity (from optical method of detection, e.g., fluorescence) with the potential of true three dimensional imaging of biological structures and processes at cellular resolution (e.g. via MRI). Microemulsions have attracted considerable interest as potential delivery vehicles for drugs with poor aqueous solubility as well as for drug detoxification. Several favorable properties of microemulsions such as transparency, easy of preparation, sterilization and nanometer droplets size (providing a relatively high interfacial area and low interfacial energy) have made them suitable for drug detoxification applications. In this presentation, highlights of advances made in synthesis, characterization and performance evaluation of nanoengineered particulate systems in targeted areas such as imaging of biological specimens using photostable nanoparticle based imaging probes, pulmonary therapeutics, and microemulsion mediated detoxification of drugs will be discussed. The toxicological assessment of selected systems will also be presented.
Despite the lack of another Flagship-class mission such as Cassini–Huygens, prospects for the future exploration of Saturn are nevertheless encouraging. Both NASA and the European Space Agency (ESA) are exploring the possibilities of focused interplanetary missions (1) to drop one or more in situ atmospheric entry probes into Saturn and (2) to explore the satellites Titan and Enceladus, which would provide opportunities for both in situ investigations of Saturn’s magnetosphere and detailed remote-sensing observations of Saturn’s atmosphere. Additionally, a new generation of powerful Earth-based and near-Earth telescopes with advanced instrumentation spanning the ultraviolet to the far-infrared promise to provide systematic observations of Saturn’s seasonally changing composition and thermal structure, cloud structures and wind fields. Finally, new advances in amateur telescopic observations brought on largely by the availability of low-cost, powerful computers, low-noise, large-format cameras, and attendant sophisticated software promise to provide regular, longterm observations of Saturn in remarkable detail.
Goosegrass biotypes from golf courses in Richmond, VA (CCV) and New Bern, NC (RB) historically treated with oxadiazon were identified as resistant compared to susceptible standard (PBU) based on comparisons of oxadiazon applied preemergence at increasing rates (0.03 to 2.24 kg ha-1). Oxadiazon at rates ≤ 2.24 kg ha-1 rate did not prevent emergence of suspected resistant CCV and RB seedlings. PBU emergence was completely prevented at 0.14 kg ha-1. Based on percent seedling emergence relative to non-treated and percent above-ground biomass reduction relative to non-treated, the oxadiazon rate at which emergence would be reduced 50% (I50) or 90% (I90) ranged from 0.12 to 0.18 kg ha-1 or 10.83 to 85.57 kg ha-1, respectively for suspected resistant CCV and RB, compared to 0.03 to 0.4 kg ha-1 or 0.12 to 0.19 kg ha-1, respectively for susceptible standard PBU. Seedling emergence data predicted 7.9 and 3.0 times greater I90 values for CCV and RB, respectively compared to biomass data. All three biotypes were completely controlled by preemergence applied labeled rates of prodiamine and indaziflam. This is the first peer-reviewed report of evolved weed resistance to oxadiazon.
There is now ample evidence that the quality of early attachment experiences shapes expectations for supportive and responsive care and ultimately serves to scaffold adaptation to the salient tasks of development. Nonetheless, few studies have identified neural mechanisms that might give rise to these associations. Using a moderately large sample of low-income male participants recruited during infancy (N = 171), we studied the predictive significance of attachment insecurity and disorganization at age 18 months (as measured in the Strange Situation Procedure) for patterns of neural activation to reward and loss at age 20 years (assessed during a reward-based task as part of a functional magnetic resonance imaging scan). Results indicated that individuals with a history of insecure attachment showed hyperactivity in (a) reward- and emotion-related (e.g., basal ganglia and amygdala) structures and (b) emotion regulation and self-referential processing (cortical midline structures) in response to positive and negative outcomes (and anticipation of those outcomes). Further, the neural activation of individuals with a history of disorganized attachment suggested that they had greater emotional reactivity in anticipation of reward and employed greater cognitive control when negative outcomes were encountered. Overall, results suggest that the quality of early attachments has lasting impacts on brain function and reward processing.
Leckrone and Adelman have established an IUE observing strategy that has yielded co-added spectra with enhanced S/N ratios for several A and B stars. New observations by Roby and Adelman using the same technique have added two new Hg-Mn stars into this sample. We have begun a long-term study of elemental abundances in this uniform, high-quality set of IUE spectra for 13 stars. We report on the first stages of this project: abundances for N, Cr, Mn, Fe, Co, and Ni. The study of the Fe- peak elements show that our data set can provide accurate abundances and that abundances obtained from UV and optical spectra often are in good agreement. This study provides the groundwork for self-consistent abundance analyses of more exotic elements in our long term project.
Aminocyclopyrachlor (AMCP) is a synthetic auxin herbicide used for broadleaf
weed control in pasture and rangeland. The tolerance and fate of AMCP within
pertinent grass species is not well understood. Research was conducted to
establish the tolerance of four grass species to AMCP application and
observe their absorption, translocation, and metabolism. Results indicate
that tall fescue is the most tolerant of AMCP at rates required for weed
control. Bahiagrass and bermudagrass are marginally tolerant, and cogongrass
is the most sensitive. Tall fescue and bahiagrass absorbed more AMCP than
bermudagrass and cogongrass, but cogongrass absorption is the most rapid and
complete within 2 days after treatment (DAT). Cogongrass and bermudagrass
translocated the least amount out of the target area, whereas bahiagrass and
tall fescue translocated the most. Radioisotope imaging revealed that tall
fescue may sequester absorbed AMCP in leaf tips. This sequestering may be
the basis of the greater tolerance to AMCP by tall fescue relative to the
other species evaluated. No metabolism of AMCP was detected in any grass
species out to 42 DAT.
The development and spread of glyphosate-resistant (GR) horseweed has increased the use of dicamba as an alternative herbicide treatment. Research evaluated suspected glyphosate-resistant horseweed populations from DeKalb (GR-1) and Cherokee (GR-2) counties, Alabama, for response to glyphosate, dicamba, and glyphosate + dicamba. Populations used for resistance determination were tested at rosette and bolt growth stages. Glyphosate resistance evaluation treatments ranged from 0 to 36.0 kg ae ha−1. Data confirmed that GR-1 and GR-2 horseweed populations were 3.0 to 38 times more resistant to glyphosate than the susceptible population, according to population, data type, and growth stage at treatment. GR-1 and GR-2 populations were further evaluated for response to dicamba. Dicamba was applied at 0 to 1.12 kg ai ha−1, both with and without the addition of glyphosate at 1.12 kg ae ha−1. All populations had similar tolerance to dicamba, with the exception of GR-2 treated at the rosette growth stage, which had ~2-fold greater tolerance. When glyphosate was tank-mixed with dicamba, the response of GR populations was similar to that of dicamba alone. Therefore, any potential resistance-management benefit of tank-mixing dicamba with glyphosate may be negated when one is attempting to control GR horseweed. Conversely, adding glyphosate to dicamba drastically enhanced control of the susceptible population at both growth stages.
The graphics processing unit has become an integral part of astronomical instrumentation, enabling high-performance online data reduction and accelerated online signal processing. In this paper, we describe a wide-band reconfigurable spectrometer built using an off-the-shelf graphics processing unit card. This spectrometer, when configured as a polyphase filter bank, supports a dual-polarisation bandwidth of up to 1.1 GHz (or a single-polarisation bandwidth of up to 2.2 GHz) on the latest generation of graphics processing units. On the other hand, when configured as a direct fast Fourier transform, the spectrometer supports a dual-polarisation bandwidth of up to 1.4 GHz (or a single-polarisation bandwidth of up to 2.8 GHz).
‘Replay' and ‘JS501’ perennial ryegrass cultivars have been conventionally bred for reduced sensitivity to glyphosate, potentially allowing the herbicide to be used for selective weed control in overseeded bermudagrass. Field experiments were conducted to evaluate optimal glyphosate application rate, regime (single and sequential applications), and timing for annual bluegrass control in bermudagrass overseeded with these cultivars. Additionally, greenhouse experiments were conducted to compare the sensitivity to glyphosate of Replay and JS501 to susceptible cultivars ‘Caddy Shack' and ‘Top Gun II' through log-logistic rate-response analysis. In field experiments, only two treatments resulted in > 90% annual bluegrass control and < 25% perennial ryegrass injury. These two treatments were a single application of 280 g ae ha−1 glyphosate in January and 140 g ha−1 followed by an additional 140 g ha−1 applied in January. Perennial ryegrass cultivars were compared using 50% inhibition (I50) values, i.e. 50% visible estimates of injury or 50% reduction in clipping weight. I50 values obtained 6 wk after treatment from injury data were 2.56, 2.64, 0.81, and 0.84 g ha−1 glyphosate for Replay, JS501, Caddy Shack, and Top Gun II, respectively. Replay and JS501 were similar in sensitivity to glyphosate and were up to four times more tolerant than Caddy Shack and Top Gun II across rating dates and data types.
Dermatitis from poison ivy is an important health problem, and considerable effort is devoted to the control of this virulent weed. Triclopyr, metsulfuron, and two fixed-ratio tank mixtures of triclopyr and metsulfuron were evaluated across a series of rates for poison ivy control. The objective was to test whether tank mixtures are more effective than triclopyr alone. Triclopyr, metsulfuron, and 9 : 1 and 8 : 2 (by weight) mixtures of these two herbicides, respectively, were applied at eight rates to 1-yr old, pot-grown poison ivy plants. Rates ranged in phytotoxicity from none to death. Percentage of control as determined from plant fresh weight reduction relative to a nontreated control was determined at 1 and 4 mo after treatment (MAT). Data were subjected to ANOVA followed by nonlinear regression. Rates required for 95% control at 1 MAT, control of regrowth at 4 MAT, and the costs of these treatments were determined for the herbicides applied alone and the mixtures. Triclopyr alone and metsulfuron alone were consistently the least and the most expensive treatments, respectively. The mixtures were intermediate to these extremes.
English ivy (Hedera helix) is an evergreen, perennial vine that was introduced from Europe and Asia and is not endemic in much of the United States. English ivy can be invasive and difficult to control once established. Four similar, but not identical, experiments were conducted in sequence to evaluate selected, POST-applied herbicides for English ivy control. English ivy plants were propagated from cuttings and container-grown to obtain a large population of uniform plants. Aminopyralid and fluroxypyr applied at 1.34 and 0.71 kg ae ha−1, which is more twice the maximum registered rate for either herbicide, were ineffective. Glyphosate and 2,4-D amine were generally more effective, but neither herbicide provided a level of control that could be deemed consistently acceptable. Glyphosate applied at 8.51 kg ae ha−1 (the highest rate evaluated) provided 69, 98, and 89% control in the second, third, and fourth experiments as determined by foliage fresh-weight reduction relative to a nontreated control. Treatment with 2,4-D at 5.60 kg ae ha−1 (the highest rate evaluated) controlled English ivy 28, 98, and 89% in the second, third, and fourth experiments, respectively. Mixtures of 2,4-D and glyphosate were generally no more effective than were the components applied alone. Metsulfuron was the most effective herbicide. Metsulfuron applied at 0.168 kg ai ha−1 controlled English ivy ≥ 97% across the three experiments in which this treatment was included. This treatment also prevented regrowth.
Annual bluegrass is a problematic turfgrass weed. Methiozolin is a new,
currently unregistered herbicide that selectively controls annual bluegrass
in desirable turfgrasses. Studies were conducted to evaluate and compare
annual bluegrass control from PRE-applied methiozolin as influenced by rate
and soil type and from POST-applied methiozolin as influenced by rate, soil
type, annual bluegrass growth stage, and treatment placement. Studies were
also conducted to evaluate foliar and root absorption and subsequent
translocation of methiozolin by annual bluegrass using radio-tracer
techniques. PRE-applied methiozolin controlled annual bluegrass > 99%.
POST-applied methiozolin resulted in < 80% control regardless of foliar
versus root exposure. POST applications are more effective at higher rates
and smaller growth stages. Foliar-plus-soil methiozolin application trended
to result in the best control, compared to foliar-only and soil-only
applications. Absorption and translocation data indicate that methiozolin is
absorbed by both leaves and roots and moderately translocates upward in the
plant toward the leaf tip with little to no basipetal translocation. Because
control is limited from a single methiozolin application (as observed in
POST experiments), successful field application of methiozolin requires
multiple and timely applications directed toward the roots and/or foliage of
Annual bluegrass is commonly controlled by acetolactate synthase
(ALS)-inhibiting herbicides in managed turfgrass. An annual bluegrass
population with suspected resistance to ALS-inhibiting herbicides was
collected from Grand National Golf Course in Opelika, AL (GN population).
Subsequent testing confirmed resistance of the GN population to
foramsulfuron, trifloxysulfuron, bispyribac-sodium (bispyribac), and
imazaquin when compared to a susceptible population collected locally at
Auburn University (AU population). Sequencing of the ALS gene revealed a
point mutation resulting in an amino acid substitution at Trp574.
Cloning of the ALS gene surrounding the Trp574 region yielded two
distinct ALS gene sequences: one producing Trp574 and one
producing Leu574. Trp574 to Leu has been previously
correlated with resistance to ALS-inhibiting herbicides. Both AU and GN gene
sequences contained other similar silent and missense mutations. This
research confirms resistance of annual bluegrass to ALS-inhibiting
herbicides with Trp574 to Leu amino acid substitution being the
most likely mode of resistance based on past literature.
The discovery of a pulsar or pulsars orbiting near the Galactic Center (GC) could offer an unprecedented probe of strong-field gravity, the properties of our galaxy's supermassive black hole and insights into the paradoxical star formation history of the region. However, searching for pulsars near the GC is severely hampered by the large electron densities along our line of sight and the scattering-induced pulse broadening of the pulsar emission observed through it. As the broadened pulse length approaches the pulsar period, the periodicity in pulsar emission becomes nearly undetectable. Searches extended to higher frequencies, in an effort to reduce scattering, suffer from reduced intrinsic flux, higher system temperatures and increased atmospheric opacity. We are currently attempting to mitigate the challenges associated with searching for pulsars near the GC by employing new wide bandwidth receivers, upgraded IF distribution systems and novel digital spectrometers in a GC pulsar search campaign at the Green Bank Telescope in West Virginia, USA.
Our search will cover two frequency bands, from 12-15 GHz (Ku Band) and 18-26 GHz (K Band), during a total of approximately 30 hours of observations, with expected characteristic 10-sigma sensitivities between 5-10 micro-Jy. Our first observations are scheduled for mid-March 2012. Here we will present the status of our observations and initial results.