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281.
282.
Amaranta Pucci Fabio Russo Maria A. Rao Liliana Gianfreda Luca Calamai Luigi P. D’Acqui 《Biology and Fertility of Soils》2012,48(4):443-451
Location and stability of a recombinant prion protein (recPrP) and its interaction with humic-like complexes were investigated
by low-temperature ashing (LTA), thermal gravimetric (TG), and scanning electron microscopy (SEM) analyses. Humic-like complexes
were obtained by abiotic polymerization of catechol, one of the possible precursors of soil humic matter, through the catalysis
of birnessite, a manganese oxide common in soil environment. The recPrP was immobilized in organomineral complexes via sorption
or entrapment. Complexes were treated by LTA, allowing the controlled removal of organic matter layer by layer, from the external
to the internal side, with minimal disturbance of mineral constituents. Thermal gravimetric and SEM analyses were performed
on specimens before and after LTA treatment. Entrapped recPrP, compared with sorbed, resulted less easily accessible to LTA
treatment and showed a higher thermal stability by TGA analyses. On the basis of these findings, we hypothesize that the processes
leading to newly formed organic complexes can enhance prion stability in soil and thus influence the environmental diffusion
of infectivity. 相似文献
283.
284.
Nutini Francesco Confalonieri Roberto Paleari Livia Pepe Monica Criscuolo Laura Porta Francesco Ranghetti Luigi Busetto Lorenzo Boschetti Mirco 《Precision Agriculture》2021,22(4):1284-1303
Precision Agriculture - Due to the low efficiency of nitrogen fertilizers in flooded rice paddies, there is a rising demand for tools able to detect crop nitrogen status in space and time to allow... 相似文献
285.
Li JZ Absher DM Tang H Southwick AM Casto AM Ramachandran S Cann HM Barsh GS Feldman M Cavalli-Sforza LL Myers RM 《Science (New York, N.Y.)》2008,319(5866):1100-1104
Human genetic diversity is shaped by both demographic and biological factors and has fundamental implications for understanding the genetic basis of diseases. We studied 938 unrelated individuals from 51 populations of the Human Genome Diversity Panel at 650,000 common single-nucleotide polymorphism loci. Individual ancestry and population substructure were detectable with very high resolution. The relationship between haplotype heterozygosity and geography was consistent with the hypothesis of a serial founder effect with a single origin in sub-Saharan Africa. In addition, we observed a pattern of ancestral allele frequency distributions that reflects variation in population dynamics among geographic regions. This data set allows the most comprehensive characterization to date of human genetic variation. 相似文献
286.
287.
Summary A joint Chilean, Italian, and United States potato (Solanum tuberosum) germplasm collecting expedition was conducted in the Guaitecas and Chonos Archipelagos, south of Chiloé Island, between
March 4 – March 21, 1990. The expedition resulted in 30 collections ofSolanum tuberosum and 1 collection ofFragaria chiloensis L. Twenty-three of the potato collections were along the salt-water-swept shores of the islands. These beach populations,
unlike the indigenous landraces in southern Chile, are self-perpetuating populations and provide useful new germplasm for
researchers interested in the origin of cultivated potatoes and in the origin ofSolanum tuberosum in Chile. 相似文献
288.
Domenico Carputo Luigi Frusciante Luigi Monti Mario Parisi Amalia Barone 《American Journal of Potato Research》2002,79(5):345-352
Tetraploid BC3 hybrids between sexually incompatible speciesSolanum commersonii andS. tuberosum were characterized for tuber quality (stolon length, tuber eye depth, chipping color from 3-month storage at 5 C, and specific gravity) and soft rot resistance traits. For all analysed morphological traits, except stolon length, genotypes resembled theS. tuberosum phenotype. On average, the specific gravity of selected genotypes was quite high (1.087), and 12 of them had a value >1.090. As for chipprocessing ability, 4.8% of genotypes chipped well directly from cold storage, and 14.3% after reconditioning. All but one of these genotypes also possessed a high specific gravity of tubers. Variability was found for resistance toErwinia carotovora subsp.carotovora. In particular, 24% of hybrids had a rotted area diameter ≤ 4 mm and were classified as resistant. The average percentage ofcommersonii-specific markers still present in the BC3 hybrids was 22%, ranging from 9% to 37%. Genotypes combining good qualitative tuber traits with a wild genome content lower than the average value of the population were selected for further breeding efforts. The importance of molecular-assisted selection is discussed. 相似文献
289.
The Mediterranean region has been regarded as a critical hotspot for desertification due to the impact of soil degradation, the land‐use changes and the climate variations. Few large‐scale studies have been devoted to analyse trends in land sensitivity to desertification in the northern Mediterranean basin. The present paper contributes to this deserving issue by quantifying the level of land sensitivity to desertification in Italy at seven points between 1960 and 2010 at a fine spatial scale. The approach used followed the Environmentally Sensitive Area scheme that assesses changes in four key themes (climate, soil, vegetation and land management) related to land degradation processes. Italian land was classified into four levels of sensitivity to desertification (non‐affected, potentially affected, fragile and critical) according to the Environmentally Sensitive Area framework. Interestingly, although land surface area classified as ‘fragile’ and ‘critical’ grew homogeneously in Italy between 1960 and 1990, the increase observed in the most recent time period was spatially clustered and contributed to reverse the polarisation in ‘structurally vulnerable’ and ‘non‐affected’ regions observed in Italy. The paper discussed these trends in the light of socioeconomic changes that occurred in Italy after World War II. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献