Pinpointing the source of a lunar meteorite: implications for the evolution of the Moon

The lunar meteorite Sayh al Uhaymir 169 consists of an impact melt breccia extremely enriched with potassium, rare earth elements, and phosphorus [thorium, 32.7 parts per million (ppm); uranium, 8.6 ppm; potassium oxide, 0.54 weight percent], and adherent regolith. The isotope systematics of the meteorite record four lunar impact events at 3909 +/- 13 million years ago (Ma), approximately 2800 Ma, approximately 200 Ma, and <0.34 Ma, and collision with Earth sometime after 9.7 +/- 1.3 thousand years ago. With these data, we can link the impact-melt breccia to Imbrium and pinpoint the source region of the meteorite to the Lalande impact crater.     

General resistance against potato virus Y introduced into a commercial potato cultivar by genetic transformation with PVYN coat protein gene

Summary Transgenic cv. Folva potato plants expressing the coat protein gene of potato virus Y strain N (PVY^N) were produced usingAgrobacterium tumefaciens mediated transformation. Forty independent transformants were selected for resistance screening. Four clones showed complete resistance to mechanical inoculation with all the five PVY isolates tested: the PVY^N isolate from which the coat protein gene was derived, two PVY^O isolates, and two PVY^NTN isolates. Two of the fully resistant clones contained only one copy of the transgene, demonstrating that it is possible by genetic engineering to obtain highly virus resistant potato clones that can also be useful in future breeding programmes.     

Ökochemische Kennwerte des Bodens

Eco-chemical parameters of soils Parameters are described which allow the ecochemical characterization of the mineral substance, of the pool of mobilizable surface bound ions, and of the pool of dissolved ions. In the soil solution (dissolved ion pool) distinction is made between parameters quantifying nutrient and acid stress and indication parameters. Indication parameters, which are derived from the anion composition of the dissolved ion pool, allow the identification of the anion source. Anion sources may be located in the ecosystem itself (HCO₃^?, NO₃^?, organic anions), may be atmospheric deposition (SO₄^2?, NO₃^?, Cl^?) and may originate from fertilization.     

Tiefengradienten der Bodenversauerung

Depth gradients of soil acidification In dystric Cambisols, developed from diabas and clay schist/greywacke in the Sösemulde (Harz), the depth gradient of the acid/base status has been assessed by measuring pH and the composition of exchangeable cations. After the soil in the root zone has acidified to within the aluminum buffer range, a marked acidification front is formed below the rooting zone. Strong acids (protons, Mn, Al ions) are buffered completely above the acidification front. Long-term measurements of the input and output of acids and bases in nine forest ecosystems in NW-Germany show that the acid input due to acid deposition into soil horizons in the Al- or Al/Fe- buffer range appears almost quantitatively as output in the seepage water from these horizons. The kind of acid responsible for the soil acidification can be identified by the anion composition of the seepage water. The deep reaching acidification is traced back to acid deposition.     

Dynamic crushing characteristics of spruce wood under large deformations

An extensive series of large deformation crushing tests with spruce wood specimens was conducted. Material orientation, lateral constraint and loading rate were varied. Regarding material orientation, a reduction in the softening effect and the general force level was observed with a higher fiber-load angle. A comparison with characteristics gained by application of Hankinson’s formula showed discrepancies in compression strength and the beginning of the hardening effect. Lateral constraint of the specimens caused a multiaxial stress state in the specimens, which was quantified with the applied measuring method. Further, a higher force level compared to specimens without lateral constraint and significant hardening effect at large deformations resulted. Thus, the influence of a multiaxial stress state on the force level could be determined. An increase in the loading rate led to higher force levels at any displacement value and material orientation.     

Simulation of a real-time process adaptation in the manufacture of high-density fibreboards using multivariate regression analysis and feedforward control

The industrial manufacturing of wood-based panels has become a highly technological process, where all parameters have to be perfectly adjusted to manufacture products of high quality. However, variations caused by differing wood characteristics as well as variations of single process parameters can cause out-of-control events. These undesirable events can be diminished by monitoring and controlling the entire manufacturing process using multivariate statistical techniques. Hence, a real-time process adaptation of an industrial scale fibreboard manufacturing process was simulated. Regression results revealed a mean normalised root mean squared error of prediction of 4.6 %, when predicting the internal bond strength of fibreboards. The regression model is regularly validated and, if necessary, recalibrated using the offline determined board properties (feedback control). Consequently, the process can immediately be adapted as soon as the board is produced (feedforward control). The investigations resulted in reliable models and revealed high potential for permanent industrial implementation.     

Inheritance of field resistance to Septoria tritici blotch in the wheat doubled-haploid population Solitär × Mazurka

Breeding for field resistance to Septoria tritici blotch (STB), caused by Mycosphaerella graminicola (anamorph: Septoria tritici), is the most suitable strategy for controlling this important disease of wheat. Although many Stb genes for resistance to single pathogen isolates have been identified in wheat, knowledge of their efficiency against natural fungal populations is lacking. In a quantitative-trait-locus (QTL) mapping approach in six environments and four locations, field resistance to STB was studied in a doubled-haploid population derived from a cross between the field-resistant cultivar Solitär and the susceptible cultivar Mazurka. After plant height as a disease escape trait was accounted for, five QTL with effects on STB response on chromosomes 5A, 6D and 7D explained 20 % of the genotypic variance; QTL × environment interactions were minor. Field resistance was conferred exclusively by alleles from Solitär, which was previously shown to carry the isolate-specific genes Stb6 and Stb11 as well as minor QTL detected with seven fungal isolates. Surprisingly, neither the Stb6 nor Stb11 isolate-specific genes nor minor QTL previously detected in Solitär were found to be involved in its field resistance. The study suggests that resistance breeding for STB should not rest solely on the deployment of Stb genes. Field tests are indispensable to show their efficacy and durability and to identify genes conferring partial field resistance to STB.     

A Review of Candidate Genes for Development of Equine Recurrent Uveitis

Equine recurrent uveitis (ERU) is a serious eye disease and the most common cause of blindness in horses. Until now, the cause of ERU is not fully understood. Persistent infections of pathogenic leptospires have been discussed. Chronic recurrent remitting episodes of inflammations and the positive therapeutic effects of corticosteroids have led to the hypothesis that ERU is an autoimmune disorder. The reason for a dysregulated autoimmune response may be linked to genetic factors. ERU shows similarities to human autoimmune uveitis with a genetic background. An association of the equine leukocyte antigen serological haplotype A9 with ERU in warmblood horses indicated that major histocompatibility complex I (MHCI) influences the development of ERU. The different types of human autoimmune and genetic uveitis, like Behçet's disease, systemic sarcoidosis, Vogt-Koyanagi-Harada syndrome, birdshot retinochoroidopathy, sympathetic ophthalmia, and acute recurrent anterior uveitis, had been associated with the human leukocyte antigen complex and genetic variants of the MHC. Furthermore non-MHC genes with a possible role in autoimmunity may also play a role in ERU-affected horses. The genes presented herein may be of interest for genome-wide association analyses of ERU-affected horses.     

Host‐specificity of the endangered thick‐shelled river mussel (Unio crassus,Philipsson 1788) and implications for conservation

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