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801.
Sara Montanari Laure Perchepied Déborah Renault Linda Frijters Riccardo Velasco Mary Horner Susan E. Gardiner David Chagné Vincent G. M. Bus Charles-Eric Durel Mickael Malnoy 《Molecular breeding : new strategies in plant improvement》2016,36(4):47
Fire blight, caused by the bacterium Erwinia amylovora (Burrill) Winslow et al., is one of the most serious diseases of pear. The development of pear cultivars with a durable resistance is extremely important for effective control of fire blight and is a key objective of most pear breeding programs throughout the world. We phenotyped seedlings from the interspecific pear population PEAR3 (PremP003, P. × bretschneideri × P. communis) × ‘Moonglow’ (P. communis) for fire blight resistance at two different geographic locations, in France and New Zealand, respectively, employing two local E. amylovora isolates. Using a genetic map constructed with single nucleotide polymorphism (SNP) and microsatellite (SSR) markers previously developed for this segregating population, we detected a major quantitative trait locus (QTL) on linkage group (LG)2 of ‘Moonglow’ (R 2 = 12.9–34.4 %), which was stable in both environments. We demonstrated that this QTL co-localizes with another major QTL for fire blight resistance previously detected in ‘Harrow Sweet’ and that the two favorable (i.e., resistant) alleles were not identical by descent. We also identified some smaller effect (R 2 = 8.1–14.8 %) QTLs derived from the susceptible parent PEAR3. We propose SNP and SSR markers linked to the large effect QTL on LG2 as candidates for marker-assisted breeding for fire blight resistance in pear. 相似文献
802.
Cooperation theories assume that interacting individuals can change their strategies under different expected payoffs, depending on their social status or social situations. When looking at sex differences in cooperation, the existing studies have found that the genders cooperate at similar frequencies. However, the majority of the data originate within Western human societies. In this paper, we explore whether there are gender differences in cooperation in China. An Iterated Prisoner’s Dilemma game with a punishment option was used to gather data about Southwest Chinese subjects in a culture in which men have a hierarchical advantage over women. Results indicate that men invested into partners significantly more than women did (34% ♂ vs. 24% ♀) while women, in turn, were more likely to defect (65% ♀ vs. 50% ♂). In this region, women have customarily held less economic power and they are used to obtain a payoff typically lower than men. We suggest that the women’s willingness to invest in cooperation has decreased throughout evolutionary time, providing us with an illustration of a culturally-driven shift towards a disparity in gender cooperation interests. 相似文献
803.
József Prechl Krisztián Papp Zoltán Hérincs Hajna Péterfy Veronika Lóránd Zoltán Szittner Andone Estonba Paolo Rovero Ilaria Paolini Jokin del Amo Maria Uribarri Maria Claudia Alcaro Otsanda Ruiz-Larra?aga Paola Migliorini László Czirják 《PloS one》2016,11(3)
Systemic lupus erythematosus is a chronic autoimmune disease with multifactorial ethiopathogenesis. The complement system is involved in both the early and late stages of disease development and organ damage. To better understand autoantibody mediated complement consumption we examined ex vivo immune complex formation on autoantigen arrays. We recruited patients with SLE (n = 211), with other systemic autoimmune diseases (n = 65) and non-autoimmune control subjects (n = 149). Standard clinical and laboratory data were collected and serum complement levels were determined. The genotype of SNP rs1143679 in the ITGAM gene was also determined. Ex vivo formation of immune complexes, with respect to IgM, IgG, complement C4 and C3 binding, was examined using a functional immunoassay on autoantigen microarray comprising nucleic acids, proteins and lipids. Complement consumption of nucleic acids increased upon binding of IgM and IgG even when serum complement levels were decreased due to consumption in SLE patients. A negative correlation between serum complement levels and ex vivo complement deposition on nucleic acid autoantigens is demonstrated. On the contrary, complement deposition on tested protein and lipid autoantigens showed positive correlation with C4 levels. Genetic analysis revealed that the non-synonymous variant rs1143679 in complement receptor type 3 is associated with an increased production of anti-dsDNA IgG antibodies. Notwithstanding, homozygous carriers of the previously reported susceptible allele (AA) had lower levels of dsDNA specific IgM among SLE patients. Both the non-synonymous variant rs1143679 and the high ratio of nucleic acid specific IgG/IgM were associated with multiple organ involvement. In summary, secondary complement deficiency in SLE does not impair opsonization of nucleic-acid-containing autoantigens but does affect other antigens and potentially other complement dependent processes. Dysfunction of the receptor recognizing complement opsonized immune complexes promotes the development of class-switched autoantibodies targeting nucleic acids. 相似文献
804.
805.
Massimo Vincenzini Roberto De Philippis Claudio Sili Riccardo Materassi 《Journal of applied phycology》1993,5(5):539-541
In order to assess the stability of molecular and rheological properties of the exopolysaccharide (EPS) produced byCyanospira capsulata the strain was cultivated under both continuous light and light-dark cycles in two culture devices, an open pond and a completely stirred reactor (CSR), having quite different surface-to-volume ratios and stirring systems. All EPS samples obtained from the cultures showed the same monosaccharidic composition and relative proportions among sugar units. However, Gel Permeation Chromatography demonstrated that EPS samples produced by cultures run in open ponds were more homogeneous in size than those obtained from cultures grown in CSR. In spite of this difference, no significant change in the flow properties was observed among the aqueous solutions of the different EPS samples. 相似文献
806.
Daniele Milanesio Maurice Saccani Riccardo Maggiora Daniela Laurino Marco Porporato 《Ecology and evolution》2016,6(7):2170-2178
The yellow‐legged Asian hornet is an invasive species of wasps, indigenous to the Southeast Asia but recently spreading in Southern Europe. Because of its exponential diffusion and its serious threat to the local honeybee colonies (and to humans as well), restraint measures are currently under investigation. We developed and tested an harmonic radar capable of tracking the flying trajectory of these insects, once equipped with a small transponder, in their natural environment. Several hornets were captured close to a small cluster of honeybee hives, tagged with different transponders and then released in order to follow the flight toward their nest. On‐field testing proved an initial maximum detection range of about 125 m in a hilly and woody area. A number of detections were clearly recorded, and preferential directions of flight were identified. The system herein described is intended as a first low‐cost harmonic radar; it proved the capability to track the hornets while flying and it permitted to test the tagging techniques. Several upgrades of the system have been identified during this work and are extensively described in the last chapter. The designed system has three major advantages over conventional harmonic radars. First and most importantly, it adopts advanced processing techniques to suppress clutter and to improve target detection. Second, it allows radar operations in complex environments, generally hilly and rich in vegetation. Finally, it can continuously track tagged insects (24/7) and in any meteorological condition, providing an effective tool in order to locate the nests of the yellow‐legged Asian hornet. 相似文献
807.
Angelo Monguzzi Francesco Bianchi Alberto Bianchi Michele Mauri Roberto Simonutti Riccardo Ruffo Riccardo Tubino Francesco Meinardi 《Liver Transplantation》2013,3(5):680-686
Optically active materials able to up‐convert the frequency of the incident radiation can be used to enhance the performance of photovoltaic and photocatalityc cells, recovering sub‐bandgap photons not directly absorbed by the devices. Actually, sensitized up‐conversion (SUC) based on multi‐component organic systems is the most promising approach for these photon energy managing processes, being efficient also at the solar irradiance. However, applications of SUC on real devices have not been yet accomplished because its conversion yield usually drops dramatically in the solid state where the low dye mobility inhibits the diffusion controlled mechanisms ruling SUC photophysics. To overcome this limit, we prepared a single‐phase elastomer (poly‐butylacrilate) doped with proper dyes (platinum (II) octaetyl‐porphyrin and 9,10‐diphenylanthracene) to fabricate an efficient photon up‐converting material. Thanks to the residual molecular diffusion provided by the soft host, and to the quenching reduction of involved metastable electronic excited‐states in a solid environment compared to a liquid one, we obtained a record SUC yield of 17% at the solid state. SUC efficiency has been studied as function of the excitation power and sample temperature, elucidating the photophysical processes at the base of the high observed yield and assessing the guidelines for the fabrication of technologically appealing low power up‐converting materials. 相似文献
808.
Andrea Riccardo Filippi Pierfrancesco Franco Patrizia Ciammella 《Reports of Practical Oncology and Radiotherapy》2012,17(5):246-250
The role of radiotherapy is well established in combined modality programs for early stage Hodgkin's lymphoma, but still debated with regards to late toxicity issues. Modern radiotherapy prescribing attitudes include lower doses and smaller fields, together with the implementation of sophisticated and dedicated delivery techniques. Aim of this review is to briefly discuss the current role of radiotherapy in this field and the potential future developments. Major trials conducted in recent years in early stage Hodgkin's lymphoma are critically reviewed and discussed with a focus on radiotherapy-related issues and with an attention to current treatment options by a “young” radiation oncologists’ perspective. 相似文献
809.
810.