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81.
82.
This paper presents the investigation of the chlorophyll and carotenoid pigments composition in monovarietal virgin olive oils produced from the five main olive varieties (Minuta, Ottobratica, Calabrese, Ogliarola, Baddarica) cultivated in Sicily (southern Italy), from four main olive varieties (DolceAgogia, Moraiolo, Leccino, Frantoio) cultivated in Umbria (central Italy), and from three main olive varieties (Leccino, Oliva Nera di Collecorto, Noccioluta) cultivated in Molise (central Italy). Reversed-phase high performance liquid chromatography using a C-30 column with photodiode array detection was used for pigments analyses. In all, 19 compounds were identified and quantified in 60 olive oils samples. The qualitative pigments pattern was similar among the varieties investigated, whereas quantitative differences were found among the different cultivars; among the varieties investigated in this work, the oils from Umbria showed the highest pigment content (34.19 ppm in average), followed by the oils from Molise (18.61 ppm in average) and the oils from Sicily which showed the lowest pigment contents (13.38 ppm in average). In general, pheophytin a was the major component (range 0.49–19.42 ppm), followed by β-carotene (range 1.27–9.30 ppm) and lutein (range 0.44–5.12 ppm). Those differences may be due to genetic factors and/or geographical differences. Moreover, auroxanthin was detected for the first time in olive oils and was detected only in olive oils from Umbria and Molise regions. The ratio between the two isochromic pigment fractions, namely the ratio between the chlorophyll and carotenoid fractions showed an average value close to unity. The lutein/β-carotene ratio was less than one in the majority of the cases. These parameters, along with other analytical parameters, could be used as indicators of typicality in olive oils. The presence of a specific pigment profile in olive oils could infact be used to guarantee the genuineness of the product, since the quality control of food requires a precise knowledge of the pigments composition of the original products.  相似文献   
83.
Replication and maintenance of mtDNA entirely relies on a set of proteins encoded by the nuclear genome, which include members of the core replicative machinery, proteins involved in the homeostasis of mitochondrial dNTPs pools or deputed to the control of mitochondrial dynamics and morphology. Mutations in their coding genes have been observed in familial and sporadic forms of pediatric and adult-onset clinical phenotypes featuring mtDNA instability. The list of defects involved in these disorders has recently expanded, including mutations in the exo-/endo-nuclease flap-processing proteins MGME1 and DNA2, supporting the notion that an enzymatic DNA repair system actively takes place in mitochondria. The results obtained in the last few years acknowledge the contribution of next-generation sequencing methods in the identification of new disease loci in small groups of patients and even single probands. Although heterogeneous, these genes can be conveniently classified according to the pathway to which they belong. The definition of the molecular and biochemical features of these pathways might be helpful for fundamental knowledge of these disorders, to accelerate genetic diagnosis of patients and the development of rational therapies. In this review, we discuss the molecular findings disclosed in adult patients with muscle pathology hallmarked by mtDNA instability.  相似文献   
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Durum wheat (Triticum durum Desf.) has potential as an adjunct in brewing given its agronomic, chemical and technological properties. The aim of this work were to identify the cultivable microflora and evaluate the technological quality of the durum wheat variety ‘Senatore Cappelli’ grown and used by a craft brewery in Sardinia, Italy. The isolated bacterial strains were mainly rhizospheric (Kocuria rizophila, Microbacterium aerolatum and Bacillus pumilus) and associated with the microbiota of wheat (Staphylococcus spp.). None have been reported previously as spoilage species in brewing. The dominant yeast genera were Cryptococcus spp. and Rhodotorula spp., followed by Saccharomyces cerevisiae. The dominant filamentous fungus genera were Alternaria and Rhizopus. Low levels of mycotoxigenic Fusarium spp., Aspergillus spp. and Penicillium spp. were isolated. However, the levels of deoxynivalenol, T2‐HT2, fumonisin, aflatoxin and ochratoxin detected in the malt and grain were below the thresholds defined by European law. Malt obtained from raw grain showed interesting technological properties, but required specific malting parameters different from those of common wheat and barley. These data suggest that the use of locally grown durum wheat in brewing can increase sustainability and reduce costs, while reinforcing the link with the terroir and promoting reduced mycotoxin levels. © 2019 The Institute of Brewing & Distilling  相似文献   
86.
A thorough analysis of the behavior of error‐correcting codes over space links affected by solar scintillation is presented. The relevant channel parameters are fixed through the development of a model based on real missions' data. Both telecommand and telemetry links are considered in fast and slow fading conditions. Besides classical coherent modulation schemes, the possibility to use noncoherent modulation schemes is considered, to eliminate the problem of phase tracking. For the case of channels with very slow fading, the use of external interleavers or erasure coding is proposed to cope with error bursts.  相似文献   
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The public domain image analysis program NIH Image (http://rsb.info.nih.gov/nih-image) has been modified and extended to produce Image SXM (http://reg.ssci.liv.ac.uk), a program that supports many of the image file formats used by various scanning probe microscope manufacturers. This article discusses the different approaches to software customization and describes the use of two sets of macros in the analysis and processing of atomic force microscopy images.  相似文献   
89.
The Journal of Supercomputing - The ongoing effort to reach the exascale computing barrier has led to a myriad of research and publications in the topic of alternative energy-efficient...  相似文献   
90.
A 2D/2D heterojunction of black phosphorous (BP)/graphitic carbon nitride (g‐C3N4) is designed and synthesized for photocatalytic H2 evolution. The ice‐assisted exfoliation method developed herein for preparing BP nanosheets from bulk BP, leads to high yield of few‐layer BP nanosheets (≈6 layers on average) with large lateral size at reduced duration and power for liquid exfoliation. The combination of BP with g‐C3N4 protects BP from oxidation and contributes to enhanced activity both under λ > 420 nm and λ > 475 nm light irradiation and to long‐term stability. The H2 production rate of BP/g‐C3N4 (384.17 µmol g?1 h?1) is comparable to, and even surpasses that of the previously reported, precious metal‐loaded photocatalyst under λ > 420 nm light. The efficient charge transfer between BP and g‐C3N4 (likely due to formed N? P bonds) and broadened photon absorption (supported both experimentally and theoretically) contribute to the excellent photocatalytic performance. The possible mechanisms of H2 evolution under various forms of light irradiation is unveiled. This work presents a novel, facile method to prepare 2D nanomaterials and provides a successful paradigm for the design of metal‐free photocatalysts with improved charge‐carrier dynamics for renewable energy conversion.  相似文献   
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