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Recently, an isoparaffin-rich jet fuel derived from camelina, a low-input nonfood oilseed crop, was flight-tested by a commercial airline. To date, all test results indicate that this hydrotreated renewable jet fuel (HRJ) not only meets stringent engine fuel and performance specifications but also reduces environmental emissions. Several scenarios are now being considered for camelina as a sustainable feedstock for advanced biofuel production. For example, growth of camelina in the Northern Plains of the United States on either marginal lands or as a rotation crop during fallow periods on existing lands already in food crop production can avoid the conflict with food cultivation and concerns with indirect land use change impacts. Updated estimates of camelina cultivation requirements and commercial scale oil recovery and refining were used to calculate life cycle greenhouse gas (GHG) emissions and energy demand for both HRJ and renewable diesel (green diesel, GD). GHG life cycle emissions for GD and HRJ are 18.0 and 22.4 g CO 2 equiv/MJ fuel, which represent savings relative to petroleum counterparts of 80% and 75%, respectively. Scenario analyses were conducted to determine response to model assumptions and data uncertainty, including allocation methodology, N fertilizer application rate, N 2 O emission factor, source of H 2 , and farm diesel consumption.

Summary Mutation rates vary between species across several orders of magnitude, with larger organisms having the highest per-generation mutation rates. Hypotheses for this pattern typically invoke physiological or population-genetic constraints imposed on the molecular machinery preventing mutations [1]. However, continuing germline cell division in multicellular eukaryotes means that organisms with longer generation times and of larger size will leave more mutations to their offspring simply as a by-product of their increased lifespan [2, 3]. Here, we deeply sequence the genomes of 30 owl monkeys (Aotus nancymaae) from 6 multi-generation pedigrees to demonstrate that paternal age is the major factor determining the number of de novo mutations in this species. We find that owl monkeys have an average mutation rate of 0.81 × 10−8 per site per generation, roughly 32% lower than the estimate in humans. Based on a simple model of reproductive longevity that does not require any changes to the mutational machinery, we show that this is the expected mutation rate in owl monkeys. We further demonstrate that our model predicts species-specific mutation rates in other primates, including study-specific mutation rates in humans based on the average paternal age. Our results suggest that variation in life history traits alone can explain variation in the per-generation mutation rate among primates, and perhaps among a wide range of multicellular organisms.

A study was conducted to compare three measurements of determining water status of grapevines (Vitis vinifera L.) in the field. Predawn leaf water potential (ΨPD), midday leaf water potential (Ψl), and midday stem water potential (Ψstem) were measured on `Chardonnay' and `Cabernet Sauvignon' grapevines grown in Napa Valley, California late in the 1999 growing season. Both cultivars had been irrigated weekly at various fractions (0, 0.5, and 1.0 for `Chardonnay' and 0, 0.5, 0.75, and 1.5 for `Cabernet') of estimated vineyard evapotranspiration (ETc) from approximately anthesis up to the dates of measurements. Predawn water potential measurements were taken beginning at 0330 hr and completed before sunrise. Midday Ψl and Ψstem measurements were taken only between 1230 and 1330 hr. In addition, net CO2 assimilation rates (A) and stomatal conductance to water vapor (gs) were also measured at midday. Soil water content (SWC) was measured in the `Chardonnay' vineyard using a neutron probe. Values obtained for ΨPD, Ψl, and Ψstem in this study ranged from about -0.05 to -0.8, -0.7 to -1.8, and -0.5 to -1.6 MPa, respectively. All three measurements of vine water status were highly correlated with one another. Linear regression analysis of Ψl and Ψstem versus ΨPD resulted in r2 values of 0.88 and 0.85, respectively. A similar analysis of Ψl as a function of Ψstem resulted in an r2 of 0.92. In the `Chardonnay' vineyard, all three methods of estimating vine water status were significantly (P < 0.01) correlated with SWC and applied amounts of water. Lastly, ΨPD, Ψl, and Ψstem were all linearly correlated with measurements of A and gs at midday. Under the conditions of this study, ΨPD, Ψl, and Ψstem represent equally viable methods of assessing the water status of these grapevines. They were all correlated similarly with the amount of water in the soil profile and leaf gas exchange as well as with one another.

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Over the last 20-80 million years the mammalian placenta has taken on a variety of morphologies through both divergent and convergent evolution. Recently we have shown that the human placenta genome has a unique epigenetic pattern of large partially methylated domains (PMDs) and highly methylated domains (HMDs) with gene body DNA methylation positively correlating with level of gene expression. In order to determine the evolutionary conservation of DNA methylation patterns and transcriptional regulatory programs in the placenta, we performed a genome-wide methylome (MethylC-seq) analysis of human, rhesus macaque, squirrel monkey, mouse, dog, horse, and cow placentas as well as opossum extraembryonic membrane. We found that, similar to human placenta, mammalian placentas and opossum extraembryonic membrane have globally lower levels of methylation compared to somatic tissues. Higher relative gene body methylation was the conserved feature across all mammalian placentas, despite differences in PMD/HMDs and absolute methylation levels. Specifically, higher methylation over the bodies of genes involved in mitosis, vesicle-mediated transport, protein phosphorylation, and chromatin modification was observed compared with the rest of the genome. As in human placenta, higher methylation is associated with higher gene expression and is predictive of genic location across species. Analysis of DNA methylation in oocytes and preimplantation embryos shows a conserved pattern of gene body methylation similar to the placenta. Intriguingly, mouse and cow oocytes and mouse early embryos have PMD/HMDs but their placentas do not, suggesting that PMD/HMDs are a feature of early preimplantation methylation patterns that become lost during placental development in some species and following implantation of the embryo.

Leaf net CO2 assimilation rate (A), stomatal conductance (g,), carboxylation efficiency, and foliar nonstructural carbohydrates were measured on mature, field-grown Vitis vlnffera L. (cv Thompson Seedless) vines that had been trunk girdled, sprayed with gibberellic acid, or both, shortly after anthesis. Girdling reduced A, g9, and carboxylatfon efficiency when measured 2 weeks after imposition of the treatments. Diumal measurements indicated that A of girdled vines was less than that of control vines between 1000 and 1800 hours. Gibberellic acid mitigated the depressing effect of girdling on g. during the same diumal measurements. The concentrations of foliar carbohydrates were greatest for the girdled vines, followed by the combination treatment and were lowest for the control vines. Foliar carbohydrates were greater for girdled vines 4 weeks after the treatments were imposed, however, by this time there was no significant difference in A between the control and girdled vines. Two and 4 weeks after the experiment was initiated root carbohydrate concentrations were less for the girdled vines when compared to the control vines. The data indicate that the reduction in A of girdled grapevines is not associated with the accumulation of leaf nonstructural carbohydrates following the girdling treatment.Alteration of the plant's source/sink relationships commonly occurs in the production of perennial horticultural crops. This is especially true for the production of seedless table grapes in California. Cultural practices used for table grape production include the use of GA3 sprays at anthesis which reduces the number of flowers that set and then an additional GA3 spray shortly thereafter which will increase berry size. Trunk girdling (the removal of a ring of phloem) also is utilized shortly after anthesis to increase berry size or later in the season to enhance fruit maturity (earlier berry coloration or accumulation of sugar). Other practices include the removal ofentire clusters or portions ofindividual clusters which will increase the size of remaining berries. Many times girdling and GA3 sprays are used together shortly after anthesis as they have a synergistic effect on increasing berry size (9). These types of results indicate that the grapevine would be an excellent system in which to study the effects of source/sink '