75 vuotta lajikkeenjalostusta Hankkijan kasvinjalostuslaitoksella

Tämä Maataloustieteellisen Aikakauskirjan numero on toimitettu vuonna 1913 perustetun Hankkijan kasvin jalostuslaitoksen 75-juhlavuoden merkeissä. Artikkelien yhteisteemana on »Jalostus ja valinta viljelyn pohjoisrajalla». Jokainen kirjoittaja työskentelee lajin tai kasviryhmän viljelyn pohjoisella raja-alueella ja käsittelee sen asettamia ongelmia kohteensa jalostamisessa tai jalostustutkimuksessa

The water vapour distribution in the Arctic lowermost stratosphere during the LAUTLOS campaign and related transport processes including stratosphere-troposphere exchange

International audienceBalloon-borne water vapour measurements during January and February 2004, which were obtained as part of the LAUTLOS campaign at Sodankylä, Finland, 67° N, were used to analyse the water vapour distribution in the wintertime Arctic lowermost stratosphere. A 2.5 km thick layer (or 30 K in the potential temperature scale) above the tropopause is characterized by a significant water vapour variability on a synoptic timescale with values between stratospheric and tropospheric, which is in good agreement with previously reported measurements. A cross-correlation analysis of ozone and water vapour confirms that this layer contains a mixture of stratospheric and tropospheric air masses. Some of the flights sampled laminae of enhanced water vapour above the tropopause. Meteorological analyses and backward trajectory calculations show that these features were related to filaments that had developed along the flanks of cut-off anticyclones, which had been active at this time over the Northern Atlantic. The role of the filaments was however not to transport water vapour from the troposphere to the stratosphere but rather to transport it within the stratosphere away from regions where intensive two-way stratosphere-troposphere exchange (STE) was identified. Intensive STE occurred around cut-off anticyclones in regions of strong winds, where calculations suggest the presence of clear-air turbulence (CAT). Evidences that CAT contributes to the troposphere-to-stratosphere transport (TST) are presented. However, statistically, relation between TST and CAT during the studied period is weak

The water vapour distribution in the Arctic lowermost stratosphere during LAUTLOS campaign and related transport processes including stratosphere-troposphere exchange

International audienceBalloon-borne water vapour measurements during January and February 2004, which were obtained as part of the LAUTLOS campaign at Sodankylä, Finland, 67° N, were used to analyse the water vapour distribution in the wintertime Arctic lowermost stratosphere. A 2.5 km thick layer (or 30 K in the potential temperature scale) above the local tropopause is characterized by a significant water vapour variability on a synoptic timescale with values between stratospheric and tropospheric, which is in good agreement with previously reported measurements. A cross-correlation analysis of ozone and water vapour confirms that this layer contains a mixture of stratospheric and tropospheric air masses. Some of the flights sampled laminae of enhanced water vapour above the tropopause. Meteorological analyses and backward trajectory calculations show that these features are related to filaments that had developed along the flanks of cut-off anticyclones, which had been active at this time over the Northern Atlantic. Cross-tropopause mass fluxes calculated following the Wei method are used to identify regions and processes that are important for stratosphere-troposphere exchange (STE) in high-latitudes. Intensive STE occurs around cut-off anticyclones in regions of strong winds, where calculations suggest the presence of developed clear-air turbulence. The decay of the filaments is also shown to be important for STE

Development of a data-assimilation system to forecast agricultural systems: A case study of constraining soil water and soil nitrogen dynamics in the APSIM model

As we face today\u27s large-scale agricultural issues, the need for robust methods of agricultural forecasting has never been clearer. Yet, the accuracy and precision of our forecasts remains limited by current tools and methods. To overcome the limitations of process-based models and observed data, we iteratively designed and tested a generalizable and robust data-assimilation system that systematically constrains state variables in the APSIM model to improve forecast accuracy and precision. Our final novel system utilizes the Ensemble Kalman Filter to constrain model states and update model parameters at observed time steps and incorporates an algorithm that improves system performance through the joint estimation of system error matrices. We tested this system at the Energy Farm, a well-monitored research site in central Illinois, where we assimilated observed in situ soil moisture at daily time steps for two years and evaluated how assimilation impacted model forecasts of soil moisture, yield, leaf area index, tile flow, and nitrate leaching by comparing estimates with in situ observations. The system improved the accuracy and precision of soil moisture estimates for the assimilation layers by an average of 42% and 48%, respectively, when compared to the free model. Such improvements led to changes in the model\u27s soil water and nitrogen processes and, on average, increased accuracy in forecasts of annual tile flow by 43% and annual nitrate loads by 10%. Forecasts of aboveground measures did not dramatically change with assimilation, a fact which highlights the limited potential of soil moisture as a constraint for a site with no water stress. Extending the scope of previous work, our results demonstrate the power of data assimilation to constrain important model estimates beyond the assimilated state variable, such as nitrate leaching. Replication of this study is necessary to further define the limitations and opportunities of the developed system

The recovery of mitotic disturbances in the root systems of gamma-ray irradiated peas

Dormant seeds of a green pea variety Rondo were irradiated with 7000 rads of gamma rays from Co60 source. The frequency of mitotic disturbances in root tip cells was analysed during the first three weeks of growth. In agreement with earlier works a rapid decrease of frequency was observed: during the 4th and 5th days of growing the proportion of disturbances was reduced from 42 to 19 per cent and it came close to the level of the control material during the third week of growth. The discussion briefly examines the importance of the »sieve of mitosis» and its relation to the »sieve of meiosis» in eliminating the changes of hereditary material during the development of the M1-generation

Moving ahead by thinking backwards: Cognitive skills, personality, and economic preferences in collegiate success

We collected personality (Big Five) and demographic characteristics, and ran incentivized experiments measuring cognitive skills (non-verbal IQ, numeracy, backward induction/planning), and economic (time, risk) preferences, with 100 students at a small public undergraduate liberal arts college in the Midwestern US as part of a larger study that collected the same measures from 1,065 trainee truckers. Using standardized (z-score) versions of our variables we analyze their relative power to predict (1) timely graduation (four years or less), (2) graduation in six years or less, and (3) final GPA. The proactive aspect of Conscientious (but not the inhibitive one) has a large and robust positive effect on all three outcomes, and Agreeableness has a robust negative effect on both graduation outcomes, but not on GPA. Economic time preferences predict graduation in four years, and GPA. Cognitive skill measures predict as expected if entered individually in a multivariate model, but when all variables compete it is only our backward induction measure ("Hit15") that weakly predicts graduation in four years, and strongly predicts graduation in six years. Trainee truckers work in a different vocational setting and their results are appropriately different, but there is a common element: Hit15 also predicts job success (completing a one year employment contract that makes training free). We interpret Hit15 as capturing a specific part of the cognitive skills required for selfmanagement in non-routine settings - thinking backward from future goals to make the best current choice - that is not well measured by existing instruments, and suggest this deserves further scientific and institutional scrutiny

Moving Ahead by Thinking Backwards: Cognitive Skills, Personality, and Economic Preferences in Collegiate Success

We collected personality (Big Five) and demographic characteristics, and ran incentivized experiments measuring cognitive skills (non-verbal IQ, numeracy, backward induction/ planning), and economic (time, risk) preferences, with 100 students at a small public undergraduate liberal arts college in the Midwestern US as part of a larger study that collected the same measures from 1,065 trainee truckers. Using standardized (z-score) versions of our variables we analyze their relative power to predict (1) timely graduation (four years or less), (2) graduation in six years or less, and (3) final GPA. The proactive aspect of Conscientious (but not the inhibitive one) has a large and robust positive effect on all three outcomes, and Agreeableness has a robust negative effect on both graduation outcomes, but not on GPA. Economic time preferences predict graduation in four years, and GPA. Cognitive skill measures predict as expected if entered individually in a multivariate model, but when all variables compete it is only our backward induction measure (Hit15) that weakly predicts graduation in four years, and strongly predicts graduation in six years. Trainee truckers work in a different vocational setting and their results are appropriately different, but there is a common element: Hit15 also predicts their job success (completing a one year employment contract that makes training free). We interpret Hit15 as capturing a specific part of the cognitive skills required for self-management in non-routine settings thinking backward from future goals to make the best current choice that is not well measured by existing instruments, and suggest this deserves further scientific and institutional scrutiny

Nuclear contamination sources in surface air of Finnish Lapland in 1965–2011 studied by means of 137Cs, 90Sr, and total beta activity

Radionuclides 137Cs and 90Sr and total beta activity were determined from air filters collected in Rovaniemi (Finnish Lapland) in1965–2011. Nuclear contamination sources present in the air filter samples as well as temporal changes in radionuclide concentrations were examined. Ozone observations and meteorological modeling were used in combination with radionuclide analyses to study the reasons behind the observed seasonal concentration variation. In general, the magnitude and variation in activity concentrations of 137Cs and 90Sr and total beta activity in the surface air of Rovaniemi in 1965–2011 corresponded well with values from other countries. However, the obtained results prove in practice that hardly any refractory or intermediate radionuclides from the destroyed Chernobyl reactor fuel were introduced to Finnish Lapland. The main source of 137Cs and 90Sr and total beta activity in the surface air of Rovaniemi in 1965–2011 has been intense atmospheric nuclear weapon testing in 1950s–1960s and later tests performed in 1965–1980, as well as leakages from underground nuclear tests in Semipalatinsk, 1966, and Novaya Zemlya, 1987. For 137Cs and total beta activity, the influence of Chernobyl and Fukushima accidents was detected.Peer reviewe