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71.
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   
74.
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   
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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   
78.
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   
79.
Graphene oxide (GO) holds high promise for diagnostic and therapeutic applications in nanomedicine but reportedly displays immunotoxicity, underlining the need for developing functionalized GO with improved biocompatibility. This study describes adverse effects of GO and amino‐functionalized GO (GONH2) during Caenorhabditis elegans development and ageing upon acute or chronic exposure. Chronic GO treatment throughout the C. elegans development causes decreased fecundity and a reduction of animal size, while acute treatment does not lead to any measurable physiological decline. However, RNA‐Sequencing data reveal that acute GO exposure induces innate immune gene expression. The p38 MAP kinase, PMK‐1, which is a well‐established master regulator of innate immunity, protects C. elegans from chronic GO toxicity, as pmk‐1 mutants show reduced tissue‐functionality and facultative vivipary. In a direct comparison, GONH2 exposure does not cause detrimental effects in the wild type or in pmk‐1 mutants, and the innate immune response is considerably less pronounced. This work establishes enhanced biocompatibility of amino‐functionalized GO in a whole‐organism, emphasizing its potential as a biomedical nanomaterial.  相似文献   
80.
Research on entrepreneurial cognition (EC) has evolved in recent years, and the aim of this contribution is to offer a clear, systematic, and bibliometric review of EC as a field of study from a more dynamic perspective, building on Socially Situated Cognition theory (SSC). Based on a data set that covers 18 years of research, from 1998 to 2016, the present study analyzes all of the 151 papers available in the Web of Science Core Collection and 15 editorials, book chapters, and books directly referring to entrepreneurial cognition. Building on our results, we divided EC studies into two stages, namely the “emerging” (1998–2007) and the “mature” (2008–2016). In addition, with this study we suggest three main topics that should be investigated in future researches: entrepreneurial action should be considered endogenous in the entrepreneurship process and the studies in the field of embodied and distributed cognition should be expanded.  相似文献   
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