Carbon partitioning and export in transgenic Arabidopsis thaliana with altered capacity for sucrose synthesis grown at low temperature: a role for metabolite transporters

We investigated the role of metabolite transporters in cold acclimation by comparing the responses of wild-type (WT) Arabidopsis thaliana (Heynh.) with that of transgenic plants over-expressing sucrose-phosphate synthase (SPSox) or with that of antisense repression of cytosolic fructose-1,6-bisphosphatase (FBPas). Plants were grown at 23 degrees C and then shifted to 5 degrees C. We compared the leaves shifted to 5 degrees C for 3 and 10 d with new leaves that developed at 5 degrees C with control leaves on plants at 23 degrees C. At 23 degrees C, ectopic expression of SPS resulted in 30% more carbon being fixed per day and an increase in sucrose export from source leaves. This increase in fixation and export was supported by increased expression of the plastidic triose-phosphate transporter AtTPT and, to a lesser extent, the high-affinity Suc transporter AtSUC1. The improved photosynthetic performance of the SPSox plants was maintained after they were shifted to 5 degrees C and this was associated with further increases in AtSUC1 expression but with a strong repression of AtTPT mRNA abundance. Similar responses were shown by WT plants during acclimation to low temperature and this response was attenuated in the low sucrose producing FBPas plants. These data suggest that a key element in recovering flux through carbohydrate metabolism in the cold is to control the partitioning of metabolites between the chloroplast and the cytosol, and Arabidopsis modulates the expression of AtTPT to maintain balanced carbon flow. Arabidopsis also up-regulates the expression of AtSUC1, and to lesser extent AtSUC2, as down-stream components facilitate sucrose transport in leaves that develop at low temperatures.info:eu-repo/semantics/publishedVersio

Review of assessment measures in the early years: Language and literacy, numeracy and social emotional development and mental health

We completed a systematic search of measures to assess language, literacy, numeracy, and socialemotional development for children up to the age of six. These included individual assessments of children’s competencies in these areas and assessments of the children’s home and early years environment. A review of the relevant competencies for these four core domains provides the basis for identifying appropriate assessments. Norm-referenced and criterion-referenced tests of children’s performance were included. At this point in their development, the majority of direct assessments of children’s competencies involve one-to-one assessments. Measures completed by proxy (by parents, care staff, or teachers) were also included and typically used for social-emotional aspects of development and assessments of the environment. All measures were evaluated for developmental appropriateness and psychometric features. One hundred and forty-six individual child assessments were identified, of which 13 had no published information and were excluded from further evaluation. For the remaining 133 assessments, a qualitative synthesis was completed where there were appropriate U.K. norms for the measure and where data was provided on reliability and validity (N = 47). We also included criterion-referenced assessments that included the key domains. In addition, we identified nine published tools reporting psychometric information for evaluating home and early learning environments. A wide range of language measures with established norms was identified. By contrast, for the domains of numeracy and literacy, fewer measures were available. However, for children in the target age range, criterion-referenced measures may be more appropriate for identifying early literacy and numeracy skills. Although there are many measures of social-emotional development available, the majority failed to meet the psychometric selection criteria. Four measures of social-emotional development captured a range of key elements of the domain. A set of questions to consider when choosing a measure to evaluate children’s abilities was developed from the review process

Interaction of Temperature and Light in the Development of Freezing Tolerance in Plants

Abstract Freezing tolerance is the result of a wide range of physical and biochemical processes, such as the induction of antifreeze proteins, changes in membrane composition, the accumulation of osmoprotectants, and changes in the redox status, which allow plants to function at low temperatures. Even in frost-tolerant species, a certain period of growth at low but nonfreezing temperatures, known as frost or cold hardening, is required for the development of a high level of frost hardiness. It has long been known that frost hardening at low temperature under low light intensity is much less effective than under normal light conditions; it has also been shown that elevated light intensity at normal temperatures may partly replace the cold-hardening period. Earlier results indicated that cold acclimation reflects a response to a chloroplastic redox signal while the effects of excitation pressure extend beyond photosynthetic acclimation, influencing plant morphology and the expression of certain nuclear genes involved in cold acclimation. Recent results have shown that not only are parameters closely linked to the photosynthetic electron transport processes affected by light during hardening at low temperature, but light may also have an influence on the expression level of several other cold-related genes; several cold-acclimation processes can function efficiently only in the presence of light. The present review provides an overview of mechanisms that may explain how light improves the freezing tolerance of plants during the cold-hardening period

Sourcing a Stone Paver from the Colonial St. Inigoes Manor, Maryland

The objective of this study is to determine the source of a limestone paver recovered from the colonial era Old Chapel Field archaeological site (18ST329-183) in St. Inigoes, Maryland. The site is in the Coastal Plain physiographic province, where there are no viable local sources of rock. As the site was a Jesuit manor, the primary hypothesis is that the stone came from England, the emigration origin point for the Maryland colonists. The secondary objective is to determine whether the stone paver was from the Jesuit Brick Chapel at St. Mary’s City (18ST1-103), reused after the chapel was torn down by 1705. Based on paleontological, lithological, and chemical analysis of the paver, sources in the Florida Platform (U.S.), Hampshire Basin (UK), Paris Basin (France), and the Belgian Basin were ruled out. The most likely source is the Aquitaine Basin in southwest France. Comparison with limestone fragments from the chapel supports reuse of the paver from the St. Mary’s City Brick Chapel

Strategic implications of valuation methods

Author's OriginalStrategy is ultimately aimed at creating shareholder value, placing valuation in a central role linking finance and strategy. Focusing on growth options, this paper uses a unique "perfect information" model to examine, from a strategy point of view, the relationship between the market value of the firm and its intrinsic, or DCF, value. Although the research is at the level of the firm, the results have implications at the level of individual strategies and projects, since a firm can be conceptualized as a collection of projects. The findings highlight the relationship between the value of growth options and macroeconomic conditions, industry characteristics, and firm-specific factors. A revised version of this paper has since been published in the journal Advances in Strategic Management. Please use this version in your citations.Alessandri, T. M., Lander, D. M., & Bettis, R. A. (2007), Strategic Implications of Valuation: Evidence from Valuing Growth Options, in Professor Brian Silverman (ed.) Real Options Theory. Advances in Strategic Management, 24, 459-48

School absence and (primary) school connectedness: evidence from the Millennium Cohort Study

School-mandated exclusion, or school absence, is on the increase in England. Earlier analyses focused on the characteristics of children, rather than the relationship with school. Using the Millennium Cohort Study, we explore the relationship between school exclusion/school absence and school satisfaction. The Millennium Cohort Study is a UK birth cohort study of around 19,000 children born at the start of the twenty-first century and includes measures relating to school satisfaction, including liking school, being interested in school and being happy. We ask: What are the exclusion risk factors? What is the predictive relationship between school satisfaction and school exclusion and school absence? And what is the predictive relationship between school exclusion and school absence and subsequent school satisfaction over time? Our analysis applied fixed effect models based on within-child comparisons across time (age 11, 14 and 17). Results confirm that Millennium Cohort Study children miss school through exclusion (9 per cent) and absence (14 per cent), are disproportionately male and have special educational needs. School satisfaction was protective; a high level of satisfaction with school at age 7 and 11 reduced the likelihood of exclusion and truancy at age 14 in secondary school. Girls who experienced primary school exclusion reported significantly lower satisfaction with secondary school. We discuss the relationship between school satisfaction and school connectedness measures, with a view to a more nuanced understanding of the interaction between school attitudes to children and children’s attitudes to school. We conclude with tentative implications for policy and future research

Preliminary Hydrogeologic Investigation of the FutureGen 2 Site in Morgan County, Illinois.

In anticipation of the FutureGen 2 carbon sequestration activities in Morgan County (Section 25, Township 16 North, Range 9 West), field work was conducted to describe shallow geologic conditions and characterize shallow groundwater quality at the site. The Illinois State Geological Survey (ISGS) drilled one shallow stratigraphic boring to 230 feet. Bedrock was encountered at 123.5 feet below the land surface. No aquifer material was encountered in the Quaternary material or in the bedrock. A shallow groundwater monitoring well was installed at a depth of 20 feet and developed to ensure water levels and water quality within the well were representative of in situ conditions. A surficial 2-D seismic survey and an electrical earth resistivity (EER) survey were conducted at the site. The seismic survey was conducted before drilling primarily to assess the presence of shallow natural gas. None was detected. An EER survey was conducted following installation of the shallow monitoring well to assess whether aquifer materials were present at other locations in the vicinity of the shallow well. Results from the EER survey indicated a slight increase in resistivity to the southwest and southeast. The higher resistivity may indicate a slight increase in the occurrence of shallow sand in those directions. Water from 10 private water supply wells and the shallow groundwater monitoring well were sampled between October 25 and November 17, 2011. Most constituent concentrations were less than the drinking water standards. Iron (Fe), manganese (Mn), nitrate (NO3), and total dissolved solids (TDS) were the only constituents whose concentrations exceeded USEPA primary or secondary standards in some of the groundwater samples. Groundwater samples from two wells contained nitrate concentrations above the EPA Maximum Contaminant Level (MCL), 10 mg NO3-N/L. The concentrations of nitrate in the samples from these wells were also significantly greater than those detected in other samples. This report summarizes results from the stratigraphic bore hole, the geophysical surveys, and analytical results from groundwater sampling.US Department of Energypublished or submitted for publicatio

Thermal limits of leaf metabolism across biomes

High-temperature tolerance in plants is important in a warming world, with extreme heat waves predicted to increase in frequency and duration, potentially leading to lethal heating of leaves. Global patterns of high-temperature tolerance are documented in animals, but generally not in plants, limiting our ability to assess risks associated with climate warming. To assess whether there are global patterns in high-temperature tolerance of leaf metabolism, we quantified Tcrit (high temperature where minimal chlorophyll a fluorescence rises rapidly and thus photosystem II is disrupted) and Tmax (temperature where leaf respiration in darkness is maximal, beyond which respiratory function rapidly declines) in upper canopy leaves of 218 plant species spanning seven biomes. Mean site-based Tcrit values ranged from 41.5 °C in the Alaskan arctic to 50.8 °C in lowland tropical rainforests of Peruvian Amazon. For Tmax, the equivalent values were 51.0 and 60.6 °C in the Arctic and Amazon, respectively. Tcrit and Tmax followed similar biogeographic patterns, increasing linearly (˜8 °C) from polar to equatorial regions. Such increases in high-temperature tolerance are much less than expected based on the 20 °C span in high-temperature extremes across the globe. Moreover, with only modest high-temperature tolerance despite high summer temperature extremes, species in mid-latitude (~20-50°) regions have the narrowest thermal safety margins in upper canopy leaves; these regions are at the greatest risk of damage due to extreme heat-wave events, especially under conditions when leaf temperatures are further elevated by a lack of transpirational cooling. Using predicted heat-wave events for 2050 and accounting for possible thermal acclimation of Tcrit and Tmax, we also found that these safety margins could shrink in a warmer world, as rising temperatures are likely to exceed thermal tolerance limits. Thus, increasing numbers of species in many biomes may be at risk as heat-wave events become more severe with climate change