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111.
Curcuma powder was used to dye cotton and polyamide 6,6 fabrics in order to produce textile-based optical pH sensors. Both fabrics showed a bright yellow color after dyeing and demonstrated color changes (towards red) when contacted with basic solutions. Color change and sensitivity differ for cotton and for polyamide. Curcuma-dyed cotton shows color changes in particular in the range of pH between 6.5 and 8.5, whilst curcuma-dyed polyamide shows a wider pH range: from 8.5 to 13.0. The stability of pH sensing to washing was evaluated. Three different kinds of washing agents were used in order to simulate the real life conditions of a garment or a cloth. Standard test methods were used when available for washing tests. The pH sensing of the curcuma-dyed fabrics demonstrated an excellent fastness to all kinds of washing. Ionic strength of the solution does not affect the color changes. Moreover, color reversibility of the fabrics was proven, too. Color change and reversibility of the fabrics was assessed by an UV-visible spectrophotometer. Spectral changes were observed at 540 nm for curcuma-dyed cotton, and at 487 and 574 nm for polyamide.  相似文献   
112.
English walnut (Juglans regia) is an important nut crop worldwide and is currently considered emerging in Italy. Botryosphaeriaceae fungi cause symptoms including cankers, discoloration and dieback, and several species are reported across the world on walnut. In this study, symptomatic trees from an orchard in Southern Italy showing branch dieback, cankers, wood discoloration and gummosis were surveyed. Three different fungi from the Botryosphaeriaceae were consistently isolated from symptomatic tissues. Representative isolates were characterized using morphological and molecular approaches based on conidial morphology, optimum growth temperature and the comparison of DNA sequence data from the ITS, tef1‐α and tub2 loci. Three species were identified: Botryosphaeria dothidea, Neofusicoccum mediterraneum and Neofusicoccum parvum. Pathogenicity tests on detached fruits and potted plants showed that all three species were pathogenic. To our knowledge, this is the first report of these Botryosphaeriaceae species causing canker and dieback on English walnut in Italy.  相似文献   
113.
Unusual and extensive dieback of European hop hornbeam (Ostrya carpinifolia) has been observed in western Slovenia and northern Italy in recent years, when extreme drought and higher temperatures were recorded. A preliminary study identified Botryosphaeria dothidea as a potential causative agent of the dieback. Further characterization of intra- and interspecies diversity of Botryosphaeriaceae collected from O. carpinifolia and other tree species in the affected area was achieved based on anamorph morphology, sequence data from the ITS rDNA and EF1-??, PCR?CRFLP analysis and AFLP profiles. The majority of the isolates analyzed were identified as B. dothidea, and in vitro pathogenicity tests re-confirmed the fungus to be an important cause of the disease. Insight into the B. dothidea population, diversity based on AFLP markers indicates that the dieback observed in O. carpinifolia is probably associated with a heterogenous population of B. dothidea, which emerged from a latent state in response to changed climate conditions. Isolates with Dothiorella-like conidia were also identified during the survey, but these were collected more rarely and appear to represent undescribed species. Isolates from Dothiorella genus expressed low pathogenicity in pathogenicity tests and proved no impact on the pathogenic ability of B. dothidea.  相似文献   
114.
Brazilian green coffee beans of Coffea arabica and Coffea canephora species were roasted to light, medium, and dark roast degrees and analyzed in relation to furan content by using an in-house validated method based on gas chromatography coupled to mass spectrometry preceded by headspace solid-phase microextraction. Furan was not detected in green coffees, whereas levels between 911 and 5852 μg/kg were found in the roasted samples. Higher concentrations were found in Coffea canephora species and darker ground coffees. Some of the potential furan precursors were observed in significant amounts in green coffee, especially sucrose and linoleic acid, but their concentrations could not be correlated to furan formation. Additionally, coffee brews were prepared from roasted ground coffees by using two different procedures, and furan levels in the beverages varied from <10 to 288 μg/kg. The factor that most influenced the furan content in coffee brew was the brewing procedure.  相似文献   
115.
The 66-kilodalton isoform of the growth factor adapter Shc (p66Shc) translates oxidative damage into cell death by acting as reactive oxygen species (ROS) producer within mitochondria. However, the signaling link between cellular stress and mitochondrial proapoptotic activity of p66Shc was not known. We demonstrate that protein kinase C beta, activated by oxidative conditions in the cell, induces phosphorylation of p66Shc and triggers mitochondrial accumulation of the protein after it is recognized by the prolyl isomerase Pin1. Once imported, p66Shc causes alterations of mitochondrial Ca2+ responses and three-dimensional structure, thus inducing apoptosis. These data identify a signaling route that activates an apoptotic inducer shortening the life span and could be a potential target of pharmacological approaches to inhibit aging.  相似文献   
116.
Hematopoietic stem cells in the bone marrow give rise to lymphoid progenitors, which subsequently differentiate into B and T lymphocytes. Here we show that the proto-oncogene LRF plays an essential role in the B versus T lymphoid cell-fate decision. We demonstrate that LRF is key for instructing early lymphoid progenitors in mice to develop into B lineage cells by repressing T cell-instructive signals produced by the cell-fate signal protein, Notch. We propose a new model for lymphoid lineage commitment, in which LRF acts as a master regulator of the cell's determination of B versus T lineage.  相似文献   
117.
Pathogenic mycobacteria resist lysosomal delivery after uptake into macrophages, allowing them to survive intracellularly. We found that the eukaryotic-like serine/threonine protein kinase G from pathogenic mycobacteria was secreted within macrophage phagosomes, inhibiting phagosome-lysosome fusion and mediating intracellular survival of mycobacteria. Inactivation of protein kinase G by gene disruption or chemical inhibition resulted in lysosomal localization and mycobacterial cell death in infected macrophages. Besides identifying a target for the control of mycobacterial infections, these findings suggest that pathogenic mycobacteria have evolved eukaryotic-like signal transduction mechanisms capable of modulating host cell trafficking pathways.  相似文献   
118.
Sulla (Hedysarum coronarium L.) is a short-lived perennial forage legume that plays a key role in cereal-based systems in semi-arid Mediterranean regions, particularly in organic production and low-input oriented agriculture. In Sicily, the species is widespread both as a wild and cultivated plant. The present study assessed the phenotypic and genetic variation among natural populations of sulla collected from different environments throughout Sicily and analysed how the patterns of phenotypic diversity varied according to the environmental parameters of each collection site. Two commercial varieties and two Sicilian agro-ecotypes were also included in the study as controls. Principal components analysis (PCA) was performed on the sites using geographic, climatic, and pedological data to assess the differences in types of collection sites. PCA was also performed on the accessions (using pheno-morphological and agronomic data) to establish the importance of different traits in explaining multivariate polymorphisms. The results showed a large degree of genetic diversity (based on ISSR markers) and variability in pheno-morphological and agronomic traits. PCA did not clearly differentiate the accessions according to their habitats of origin, but in some cases accessions from the same habitat had a tendency to group together. The agronomic attributes of several populations were more pronounced than those of the controls. The observed variability may be valuable when selecting for H. coronarium varieties suitable for various uses (e.g., hay production, grazing, soil protection).  相似文献   
119.
Reducing the level of infection of cereal heads caused by Fusarium and associated mycotoxin accumulation in grains is of a high priority in order to secure the yield, agronomic performance, and food and feed safety from field to table. Strategies to tackle the problem have been proposed at many levels, including greater knowledge of the biology of toxigenic fungi and of plant–pathogen interactions, monitoring activities which extend from the field to the end-products, pre-breeding, breeding and transgenesis to develop new resistant plant varieties, crop protection based on synthetic or natural molecules, biocontrol of fungal populations, the development and use of models that take into account the climatic conditions, and the adoption of technological protocols for reducing or inactivating mycotoxins. This review article highlights that the problem is very complex but that the scientific community continues to produce important knowledge and potential solutions.  相似文献   
120.
A multiplex polymerase chain reaction (PCR) method coupled with a restriction analysis of PCR products (PCR with restriction fragment length polymorphism) was developed for the simultaneous detection of bovine herpesvirus 1, bovine herpesvirus 2, and bovine herpesvirus 4 infections. The specificity, sensitivity, and practical diagnostic applicability of this method were evaluated. This assay may be also adapted to the diagnosis of suid herpesvirus 1 and equine herpesviruses 1 and 3 and could become a powerful diagnostic tool.  相似文献   
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