Phenotypic analyses of multi-environment data for two diverse tetraploid potato collections: comparing an academic panel with an industrial panel

Phenotypic analyses of two different association panels of tetraploid potato cultivars are presented. Association panels are sets of variously related genotypes assembled for association analysis purposes. The aims of this research were to inspect, analyse and compare two phenotypic data sets, a first step in association mapping analysis. A first panel of 205 contemporary and historical cultivars, selected to represent the commercial potato germplasm pool, was evaluated in two trials in 2006, one on sandy soil and the other on clay soil, both with two replications. It was called the academic panel. Data for the second panel with 299 genotypes were compiled from contributions from five breeding companies and included 66 locations and 18 years. Each of the participating breeding companies contributed data from their clonal selection programmes for 38 advanced breeding clones and a series of standard cultivars. It was called the industrial panel. Variance components for genotypic main effects and genotype-by-environment interactions were calculated, and estimates for the random genotypic main effects were produced. The genotypic main effects for 19 agro-morphological and quality traits were used to study trait by trait correlations within each panel. In addition, for the genotypes shared by both panels, the correlation of genetic main effects between the panels was investigated. The heritability of all traits was high and no large differences were observed between panels. Coefficients of trait variation were highly correlated (r¿=¿0.9) for both panels and trait by trait correlations in both panels showed highly similar patterns. These results demonstrate that a single-year balanced field trial as well as using breeders’ records yields robust phenotypic information that can be used in a genome-wide association study. Issues related to data management and definition of traits are discussed

Comparing powder magnetization and transport critical current of Bi,Pb(2223) tapes

The magnetic field dependence of the critical current in (Bi,Pb)/sub 2/Sr/sub 2/Ca/sub 2/Cu/sub 3/O/sub 10+x/ tapes is compared with the magnetization response of isolated grains extracted from the tapes. Special attention is paid to the low-field behavior. The goal of the experiment is to test the widely-used hypothesis that current paths in these tapes contain both weak- and strong- linked branches, which in low field act in parallel. The data agree with this hypothesis; at temperatures above 50 K the powder magnetization drops off exponentially from the self-field to the irreversibility field, while the transport and magnetization currents in the intact tapes show an extra low-field component. Below 50 K the powder behavior becomes less straightforward, but the parallel-path picture in the tapes still holds

Bewegingsruimte voor mobiliteit : een studie naar de efficiëntie van lokale ruimtelijke inrichtingsvormen in termen van tijd, ruimte en milieubelasting

In deze publicatie zullen de keuzemogelijkheden van een aantal ruimtelijke configuraties op lokaal niveau voor personen afkomstig uit verschillende huishoudenstypen worden vastgesteld en met elkaar worden vergeleken. De huishoudenstypen worden bepaald aan de hand van drie dimensies: arbeidsparticipatie, aanwezigheid van kinderen en levensfase. We hebben drie scenario's geformuleerd aan de hand waarvan de betekenis van ruimtelijke inrichting op de mogelijkheden van personen om verschillende vervoerwijzen to gebruiken, geanalyseerd kunnen worden. We hebben die inrichtingsdimensies geselecteerd waarvan we verwachten dat ze een groot effect op die vervoersmogelijkheden en een grote beleidsrelevantie hebben. De volgende ruimtelijke configuraties staan centraal in deze studie: concentratie-spreiding van consumentenvoorzieningen menging `rode' (verstedelijking) en groene' functies (groenvoorzieningen en water) waarbij gevarieerd wordt in woningdichtheid parkeren op afstand van de woning De scenario's zullen getoetst worden aan de hand van drie criteria: keuzemogelijkheden: in alle scenario's zal vastgesteld worden welke veranderingen, ten opzichte van de huidige situatie, zullen optreden in de keuzemogelijkheden van uiteenlopende huishoudenstypen om van andere vervoerwijzen dan de auto gebruik to maken voor het uitvoeren van gegeven activiteitenprogramma's (dagelijkse activiteiten). Met dit criterium kan beoordeeld worden of verschillende huishoudenstypen hun dagelijkse activiteiten in een bepaald scenario efficienter kunnen uitvoeren of juist in de problemen komen bij her uitvoeren ervan. autokilometrage: de scenario's zullen beoordeeld worden op her aantal afgelegde autokilometers reistijd: de reistijd die benodigd is om activiteiten binnen de alternatieve ruimtelijke configuraties te ontplooie

Critical current versus strain research at the University of Twente

At the University of Twente a U-shaped spring has been used to investigate the mechanical properties of a large variety of superconducting tapes and wires. Several mechanisms are responsible for the degradation of critical current as a function of applied strain. A change in its intrinsic parameters causes a reversible critical current dependence in Nb3Sn. The critical current reaches a maximum at a wire-dependent tensile strain level, and decreases when this tensile strain is either released or further increased. In Bi-based tapes the critical current is virtually insensitive to tensile strain up to a sample-dependent irreversible strain limit. When this limit is exceeded, the critical current decreases steeply and irreversibly. This behaviour is attributed to microstructural damage to the filaments. This cracking of the filaments is verified by a magneto-optical strain experiment. Recent experiments suggest that in MgB2 the degradation of critical current is caused by a change in intrinsic properties and damage to the microstructure. Magneto-optical imaging can be used to investigate the influence of applied strain on the microstructure of MgB2, as is done successfully with Bi-based tapes. In all these conductors the thermal precompression of the filaments plays an important role. In Nb3Sn it determines the position of the maximum and in Bi-based and MgB2 conductors it is closely related to the irreversible strain limit

Maritime aerosol network as a component of AERONET - First results and comparison with global aerosol models and satellite retrievals

The Maritime Aerosol Network (MAN) has been collecting data over the oceans since November 2006. Over 80 cruises were completed through early 2010 with deployments continuing. Measurement areas included various parts of the Atlantic Ocean, the Northern and Southern Pacific Ocean, the South Indian Ocean, the Southern Ocean, the Arctic Ocean and inland seas. MAN deploys Microtops hand-held sunphotometers and utilizes a calibration procedure and data processing traceable to AERONET. Data collection included areas that previously had no aerosol optical depth (AOD) coverage at all, particularly vast areas of the Southern Ocean. The MAN data archive provides a valuable resource for aerosol studies in maritime environments. In the current paper we present results of AOD measurements over the oceans, and make a comparison with satellite AOD retrievals and model simulations

The construction of a linkage map of Alstroemeria aurea by AFLP markers

An AFLP based linkage map has been generated for the ornamental cropspecies Alstroemeria aurea. In view of the large genome size of Alstroemeria (25,000 Mb) the number of selective nucleotides for AFLPamplification was increased to EcoRI+4/MseI+4 to generatefingerprints of moderate complexity. In addition, markers were generatedwith the enzyme combination Sse/Mse, where Sse8387I is an8-cutter, thereby reducing AFLP template complexity. Segregation of 374AFLP polymorphisms was recorded in the F1 of an intraspecific A. aurea cross (A002 × A003). The map consisted of 8 A002 and 10A003 linkage groups with 122 and 214 markers covering 306.3 and605.6 cM, respectively. The two maps were integrated by using the21% of the AFLP markers that were heterozygous in both parents, and31% of the markers remained unlinked. Pollen color was assigned tolinkage group A002-6. The enzyme combinations EcoRI+4/MseI+4 and Sse+2/MseI+3 generated 80 and 30 clear bandsper lane with 16 and 9 polymorphic markers, respectively. Twenty percentof the EcoRI+4/MseI+4 primer combinations resulted infingerprints that were disturbed by a few excessively thick bands (55 outof 288 primer combinations). We conclude that fingerprints and markersgenerated with the eight-cutter enzyme Sse8387I, in combination with+2/+3 selective nucleotides (Sse+2/MseI+3) are superior toEcoRI+4/MseI+

Genetic diversity of Chilean and Brazilian Alstroemeria species assessed by AFLP analysis

One to three accessions of 22 Alstroemeria species, an interspecific hybrid (A. aurea ́ A. inodora), and single accessions of Bomarea salsilla and Leontochir ovallei were evaluated using the AFLP-marker technique to estimate the genetic diversity within the genus Alstroemeria. Three primer combinations generated 716 markers and discriminated all Alstroemeria species. The dendrogram inferred from the AFLP fingerprints supported the conjecture of the generic separation of the Chilean and Brazilian Alstroemeria species. The principal co-ordinate plot showed the separate allocation of the A. ligtu group and the allocation of A. aurea, which has a wide range of geographical distribution and genetic variation, in the middle of other Alstroemeria species. The genetic distances, based on AFLP markers, determined the genomic contribution of the parents to the interspecific hybrid