Development of fad7-1 single mutant Arabidopsis thaliana plants that are resistant to aphids

Aphids are a group of sap-feeding insects that attack most of the world’s crops. The loss of function of fatty acid desaturase7 (FAD7) in Solanum lycopersicum (tomato plant) induces aphid resistance that is dependent upon the accumulation of plant defense hormones such as salicylic acid (SA). Tomato lacks most of the genetic resources found in the model plant Arabidopsis (Arabidopsis thaliana). There is an analogous fad7-1 line of Arabidopsis; however, the line has a background mutation, the glabra-1 (gl1), that causes the absence of trichomes (small hairs), which are essential to plant defense. In order to study aphid resistance, a single mutant line of fad7-1 mutants were developed using cross breeding between the fad7-1/gl1 mutant and wild-type plants. Homozygous fad7-1 mutants were then identified using the Kasajima DNA extraction method, followed by the use of single nucleotide polymorphism-polymerase chain reaction (SNP-PCR) primers using allele-specific PCR. A phenotypic screening was then performed to screen out the plants with the glabra-1 mutation using the presence or absence of trichomes. Two single Arabidopsis fad7-1 mutant lines were identified, and subsequently verified using a bioassay to be aphid resistant relative to other genotypes as seen in tomato

Do Complexity Measures of Frontal EEG Distinguish Loss of Consciousness in Geriatric Patients Under Anesthesia?

While geriatric patients have a high likelihood of requiring anesthesia, they carry an increased risk for adverse cognitive outcomes from its use. Previous work suggests this could be mitigated by better intraoperative monitoring using indexes defined by several processed electroencephalogram (EEG) measures. Unfortunately, inconsistencies between patients and anesthetic agents in current analysis techniques have limited the adoption of EEG as standard of care. In attempts to identify new analyses that discriminate clinically-relevant anesthesia timepoints, we tested 1/f frequency scaling as well as measures of complexity from nonlinear dynamics. Specifically, we tested whether analyses that characterize time-delayed embeddings, correlation dimension (CD), phase-space geometric analysis, and multiscale entropy (MSE) capture loss-of-consciousness changes in EEG activity. We performed these analyses on EEG activity collected from a traditionally hard-to-monitor patient population: geriatric patients on beta-adrenergic blockade who were anesthetized using a combination of fentanyl and propofol. We compared these analyses to traditional frequency-derived measures to test how well they discriminated EEG states before and after loss of response to verbal stimuli. We found spectral changes similar to those reported previously during loss of response. We also found significant changes in 1/f frequency scaling. Additionally, we found that our phase-space geometric characterization of time-delayed embeddings showed significant differences before and after loss of response, as did measures of MSE. Our results suggest that our new spectral and complexity measures are capable of capturing subtle differences in EEG activity with anesthesia administration-differences which future work may reveal to improve geriatric patient monitoring

Use of Py-GC/MS Analysis Techniques in Animal Waste Management: A Preliminary Survey of Dairy Manures

The increasing practice of industrial-scale agriculture tends to concentrate large masses of animal waste in relatively compact areas, potentially leading to excessive release of polluting nutrients into waterways during major storms. Anaerobic treatment conditions are generally favored to conserve nitrate N as an agricultural commodity. However, overall N contents in waste are often in excess of crop fertilization needs: storing excess N in soluble nitrate form increases pollution potential. Thus the perceived needs of agriculture and society-at-large become at odds. Organic nitrogen forms (e.g., proteins) are more environmentally stable and are less subject to unintentional release. Although U.S. farmers tend to view it with disfavor, non-aqueous (aerobic) treatment such as composting holds potential for storing nitrogen in a more stable, environmentally-benign form. Six dairy farm (DF) waste samples were collected. The two samples discussed herein, DF4 and DF6, were chosen as representative of two biochemically different waste treatment scenarios: anaerobic versus aerobic. DF4, taken from a six-week old pit sludge at a depth of 80 cm, was olive green and exhibited odor characteristic of anaerobic conditions. DF6 was taken from older, mixed-age, lot-edge spillover and was open to the air and well-drained, but partly sheltered. DF6 was browner in color than DF4 and had an earthy odor. Sub-samples were dried, crushed, and cryo-fractured as preparation for pyrolysis. Significant differences between the two pyrolyzates were noted: DF4 is strongly enriched in fatty acids relative to DF6. As anaerobic systems tend to be lower in pH, this might be expected. A more detailed examination of the pyrograms reveals that, while both have many compounds in common, such as the methoxyphenols derived from the plant matter in the feed, relative proportions may vary considerably. The DF6 pyrolyzate appears to be relatively depleted in n-alkanes and enriched in organonitrogen compounds (indoles and dipeptides). This conservation of organic N lends support to the idea that aerobic manure management, such as by composting, could be a more desirable agricultural practice

Bacterial community profiles and Vibrio parahaemolyticus abundance in individual oysters and their association with estuarine ecology

Oysters naturally harbor the human gastric pathogen Vibrio parahaemolyticus, but the nature of this association is unknown. Because microbial interactions could influence the accumulation of V. parahaemolyticus in oysters, we investigated the composition of the microbiome in water and oysters at two ecologically unique sites in the Great Bay Estuary, New Hampshire using 16s rRNA profiling. We then evaluated correlations between bacteria inhabiting the oyster with V. parahaemolyticus abundance quantified using a most probable number (MPN) analysis. Even though oysters filter-feed, their microbiomes were not a direct snapshot of the bacterial community in overlaying water, suggesting they selectively accumulate some bacterial phyla. The microbiome of individual oysters harvested more centrally in the bay were relatively more similar to each other and had fewer unique phylotypes, but overall more taxonomic and metabolic diversity, than the microbiomes from tributary-harvested oysters that were individually more variable with lower taxonomic and metabolic diversity. Oysters harvested from the same location varied in V. parahaemolyticus abundance, with the highest abundance oysters collected from one location. This study, which to our knowledge is the first of its kind to evaluate associations of V. parahaemolyticus abundance with members of individual oyster microbiomes, implies that sufficient sampling and depth of sequencing may reveal microbiome members that could impact V. parahaemolyticus abundance

Detection and Mapping of Quantitative Trait Loci that Determine Responsiveness

Exposure to 70% N2O evokes a robust antinociceptive effect in C57BL/6 (B6) but not in DBA/2 (D2) inbred mice. This study was conducted to identify quantitative trait loci (QTL) in the mouse genome that might determine responsiveness to N2O. Offspring from the F2 generation bred from B6 and D2 progenitors exhibited a broad range of responsiveness to N2O antinociception as determined by the acetic acid-induced abdominal constriction test. QTL analysis was then used to dissect this continuous trait distribution into component loci, and to map them to broad chromosomal regions. To this end, 24 spleens were collected from each of the following four groups: male and female F2 mice responding to 70% N2O in oxygen with 100% response (high-responders); and male and female F2 mice responding with 0% response (low-responders). Genomic DNA was extracted from the spleens and genotyped with simple sequence length polymorphism MapPairs markers. Findings were combined with findings from the earlier QTL analysis from BXD recombinant inbred mice [Brain Res 725 (1996) 23]. Combined results revealed two significant QTL that influence responsiveness to nitrous oxide on proximal chromosome 2 and distal chromosome 5, and one suggestive QTL on midchromosome 18. The chromosome 2 QTL was evident only in males. A significant interaction was found between a locus on chromosome 6 and another on chromosome 13 with a substantial effect on N2O antinociception

Notes on the Natural History of Lasiurus borealis in Arkansas

Since June 1982 we have studied various aspects of red bat ecology in Arkansas with emphasis on field work in the Ouachita Mountains and examination of specimens submitted to the Arkansas Department of Health Rabies Laboratory (ADHRL).This study reports on continued field work in the Ouachita Mountains using radiotelemetry and updates information regarding red bats submitted to the ADHRL through December 1996. In addition, we revisited a cave previously reported to contain a large number of red bat skull and skeletal remains. We also report remains from another cave system in northcentral Arkansas. These investigations have yielded additional information on distribution, growth and development of young, litter size, use of atypical roosts, active period and hibernation roost site selection, copulation, and incidence of rabies

Host-selected mutations converging on a global regulator drive an adaptive leap towards symbiosis in bacteria

Host immune and physical barriers protect against pathogens but also impede the establishment of essential symbiotic partnerships. To reveal mechanisms by which beneficial organisms adapt to circumvent host defenses, we experimentally evolved ecologically distinct bioluminescent Vibrio fischeri by colonization and growth within the light organs of the squid Euprymna scolopes. Serial squid passaging of bacteria produced eight distinct mutations in the binK sensor kinase gene, which conferred an exceptional selective advantage that could be demonstrated through both empirical and theoretical analysis. Squid-adaptive binK alleles promoted colonization and immune evasion that were mediated by cell-associated matrices including symbiotic polysaccharide (Syp) and cellulose. binK variation also altered quorum sensing, raising the threshold for luminescence induction. Preexisting coordinated regulation of symbiosis traits by BinK presented an efficient solution where altered BinK function was the key to unlock multiple colonization barriers. These results identify a genetic basis for microbial adaptability and underscore the importance of hosts as selective agents that shape emergent symbiont populations

Lifetime predictions for the Solar Maximum Mission (SMM) and San Marco spacecraft

Lifetime prediction techniques developed by the Goddard Space Flight Center (GSFC) Flight Dynamics Division (FDD) are described. These techniques were developed to predict the Solar Maximum Mission (SMM) spacecraft orbit, which is decaying due to atmospheric drag, with reentry predicted to occur before the end of 1989. Lifetime predictions were also performed for the Long Duration Exposure Facility (LDEF), which was deployed on the 1984 SMM repair mission and is scheduled for retrieval on another Space Transportation System (STS) mission later this year. Concepts used in the lifetime predictions were tested on the San Marco spacecraft, which reentered the Earth's atmosphere on December 6, 1988. Ephemerides predicting the orbit evolution of the San Marco spacecraft until reentry were generated over the final 90 days of the mission when the altitude was less than 380 kilometers. The errors in the predicted ephemerides are due to errors in the prediction of atmospheric density variations over the lifetime of the satellite. To model the time dependence of the atmospheric densities, predictions of the solar flux at the 10.7-centimeter wavelength were used in conjunction with Harris-Priester (HP) atmospheric density tables. Orbital state vectors, together with the spacecraft mass and area, are used as input to the Goddard Trajectory Determination System (GTDS). Propagations proceed in monthly segments, with the nominal atmospheric drag model scaled for each month according to the predicted monthly average value of F10.7. Calibration propagations are performed over a period of known orbital decay to obtain the effective ballistic coefficient. Progagations using plus or minus 2 sigma solar flux predictions are also generated to estimate the despersion in expected reentry dates. Definitive orbits are compared with these predictions as time expases. As updated vectors are received, these are also propagated to reentryto continually update the lifetime predictions

Religiosity, Alcohol Use Attitudes, and Alcohol Use in a National Sample of Adolescents

The purpose of this study was to investigate alcohol use attitudes as a mediator of the relationship between religiosity and the frequency of past month alcohol use in a national sample of adolescents. Data were drawn from 18,314 adolescents who participated in the 2006 and 2007 National Survey on Drug Use and Health. Variables included religiosity, alcohol use attitudes, and past month frequency of alcohol use. Structural equation modeling was used to test alcohol use attitudes as a mediator of the relationship between religiosity and frequency of alcohol use and to test model invariance across 4 racial/ethnic groups. Results suggest that alcohol use attitudes partially mediate the relationship between religiosity and frequency of alcohol use. Furthermore, while the pattern of these relationships is similar across racial/ethnic groups, the magnitude of alcohol use attitudes on frequency of alcohol use differed. Implications for prevention programs include targeting alcohol use attitudes in a variety of settings

Contribution of Amino Acid Region 659−663 of Factor Va Heavy Chain to the Activity of Factor Xa within Prothrombinase†,‡

ABSTRACT: Factor Va, the cofactor of prothrombinase, is composed of heavy and light chains associated noncovalently in the presence of divalent metal ions. The COOH-terminal region of the heavy chain contains acidic amino acid clusters that are important for cofactor activity. In this work, we have investigated the role of amino acid region 659-663, which contains five consecutive acidic amino acid residues, by site-directed mutagenesis. We have generated factor V molecules in which all residues were mutated to either lysine (factor V 5K) or alanine (factor V 5A). We have also constructed a mutant molecule with this region deleted (factor V Δ659-663). The recombinant molecules along with wild-type factor V (factor V WT) were transiently expressed in mammalian cells, purified, and assessed for cofactor activity. Two-stage clotting assays revealed that the mutant molecules had reduced clotting activities compared to that of factor Va WT. Kinetic analyses of prothrombinase assembled with the mutant molecules demonstrated diminished k cat values, while the affinity of all mutant molecules for factor Xa was similar to that for factor Va WT. Gel electrophoresis analyses of plasma-derived and recombinant mutant prothrombin activation demonstrated delayed cleavage of prothrombin at both Arg 320 and Arg 271 by prothrombinase assembled with the mutant molecules, resulting i