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91.
Alessandro Ricci Michela Fratini Antonio Bianconi 《Journal of Superconductivity and Novel Magnetism》2009,22(3):305-308
We report the temperature-dependent x-ray powder diffraction of the FeAs-based superconductors in the range between 300 and
95 K. In the case of NdOFeAs we have detected the structural phase transition from the tetragonal phase, with P4/nmm space
group, to the orthorhombic phase, with Cmma space group, over a broad temperature range from 150 to 120 K, centered at T
0∼137 K. This transition is reduced, by about ∼30 K, by the internal chemical pressure going from LaOFeAs to NdOFeAs. On the
contrary, the superconducting critical temperature increases from 27 to 51 K going from LaOFeAs to NdOFeAs doped samples.
The FeAs layers in all undoped “1111” and “122” systems suffer a tensile misfit strain. The tensile misfit strain is reduced
in “1111” and in “122” samples and at optimum doping the misfit strain is close to zero. This result shows that the normal
striped orthorhombic Cmma phase competes with the superconducting tetragonal phase. In the orthorhombic clusters the charges
can move only along the stripes in the b direction and are localized by the magnetic interaction. 相似文献
92.
Benedetta Chianucci Alice Grossi Gianluca DellOrso Elena Palmisani Marina Lanciotti Paola Terranova Filomena Pierri Michela Lupia Luca Arcuri Marica Laurino Isabella Ceccherini Fabian Beier Carlo Dufour Francesca Fioredda Maurizio Miano 《International journal of molecular sciences》2022,23(23)
In recent years, the knowledge about the immune-mediated impairment of bone marrow precursors in immune-dysregulation and autoimmune disorders has increased. In addition, immune-dysregulation, secondary to marrow failure, has been reported as being, in some cases, the most evident and early sign of the disease and making the diagnosis of both groups of disorders challenging. Dyskeratosis congenita is a disorder characterized by premature telomere erosion, typically showing marrow failure, nail dystrophy and leukoplakia, although incomplete genetic penetrance and phenotypes with immune-dysregulation features have been described. We report on a previously healthy 17-year-old girl, with a cousin successfully treated for acute lymphoblastic leukemia, who presented with leukopenia and neutropenia. The diagnostic work-up showed positive anti-neutrophil antibodies, leading to the diagnosis of autoimmune neutropenia, a slightly low NK count and high TCR-αβ+-double-negative T-cells. A next-generation sequencing (NGS) analysis showed the 734C>A variant on exon 6 of the TINF2 gene, leading to the p.Ser245Tyr. The telomere length was short on the lymphocytes and granulocytes, suggesting the diagnosis of an atypical telomeropathy showing with immune-dysregulation. This case underlines the importance of an accurate diagnostic work-up of patients with immune-dysregulation, who should undergo NGS or whole exome sequencing to identify specific disorders that deserve targeted follow-up and treatment. 相似文献
93.
Teodolinda Di Risi Mariella Cuomo Roberta Vinciguerra Sara Ferraro Rosa Della Monica Davide Costabile Michela Buonaiuto Federica Trio Ettore Capoluongo Roberta Visconti Eleonora Riccio Antonio Pisani Lorenzo Chiariotti 《International journal of molecular sciences》2022,23(20)
Anderson–Fabry disease (FD) is an X-linked disease caused by a functional deficit of the α-galactosidase A enzyme. FD diagnosis relies on the clinical manifestations and research of GLA gene mutations. However, because of the lack of a clear genotype/phenotype correlation, FD diagnosis can be challenging. Recently, several studies have highlighted the importance of investigating DNA methylation patterns for confirming the correct diagnosis of different rare Mendelian diseases, but to date, no such studies have been reported for FD. Thus, in the present investigation, we analyzed for the first time the genome-wide methylation profile of a well-characterized cohort of patients with Fabry disease. We profiled the methylation status of about 850,000 CpG sites in 5 FD patients, all carrying the same mutation in the GLA gene (exon 6 c.901C>G) and presenting comparable low levels of α-Gal A activity. We found that, although the whole methylome profile did not discriminate the FD group from the unaffected one, several genes were significantly differentially methylated in Fabry patients. Thus, we provide here a proof of concept, to be tested in patients with different mutations and in a larger cohort, that the methylation state of specific genes can potentially identify Fabry patients and possibly predict organ involvement and disease evolution. 相似文献
94.
The problem of automatically selecting the pose of a 3D object that corresponds to the most informative and intuitive view of the shape is known as the best view problem. In this paper we address the selection of the best view driven by the meaningful features of the shape, in order to maximize the visibility of salient components from the context or from the application point of view. Meaningful features can be automatically detected by means of semantic-oriented segmentations: we tested several approaches with very pleasant results in the automatic generation of thumbnails for large 3D model databases. 相似文献
95.
Barbara Peruzzi Enrica Urciuoli Michela Mariani Laura Chioma Luigi Tomao Ilaria Montano Mattia Algeri Rosa Luciano Danilo Fintini Melania Manco 《International journal of molecular sciences》2023,24(1)
Excess body weight has been considered beneficial to bone health because of its anabolic effect on bone formation; however, this results in a poor quality bone structure. In this context, we evaluated the involvement of circulating extracellular vesicles in the impairment of the bone phenotype associated with obesity. Circulating extracellular vesicles were collected from the plasma of participants with normal weight, as well as overweight and obese participants, quantified by flow cytometry analysis and used to treat mesenchymal stromal cells and osteoblasts to assess their effect on cell differentiation and activity. Children with obesity had the highest amount of circulating extracellular vesicles compared to controls. The treatment of mesenchymal stromal cells with extracellular vesicles from obese participants led to an adipogenic differentiation in comparison to vesicles from controls. Mature osteoblasts treated with extracellular vesicles from obese participants showed a reduction in differentiation markers in comparison to controls. Children with obesity who regularly performed physical exercise had a lower circulating extracellular vesicle amount in comparison to those with a sedentary lifestyle. This pilot study demonstrates how the high amount of circulating extracellular vesicles in children with obesity affects the bone phenotype and that physical activity can partially rescue this phenotype. 相似文献
96.
Mangrove forests as a nature-based solution for coastal flood protection: Biophysical and ecological considerations
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Rosanna van Hespen Zhan Hu Bas Borsje Michela De Dominicis Daniel A. Friess Svetlana Jevrejeva Maarten G. Kleinhans Maria Maza Celine E. J. van Bijsterveldt Tom Van der Stocken Bregje van Wesenbeeck Danghan Xie Tjeerd J. Bouma 《水科学与水工程》2023,16(1):1-13
Nature-based coastal protection is increasingly recognised as a potentially sustainable and cost-effective solution to reduce coastal flood risk. It uses coastal ecosystems such as mangrove forests to create resilient designs for coastal flood protection. However, to use mangroves effectively as a nature-based measure for flood risk reduction, we must understand the biophysical processes that govern risk reduction capacity through mangrove ecosystem size and structure. In this perspective, we evaluate the current state of knowledge on local physical drivers and ecological processes that determine mangrove functioning as part of a nature-based flood defence. We show that the forest properties that comprise coastal flood protection are well-known, but models cannot yet pinpoint how spatial heterogeneity of the forest structure affects the capacity for wave or surge attenuation. Overall, there is relatively good understanding of the ecological processes that drive forest structure and size, but there is a lack of knowledge on how daily bed-level dynamics link to long-term biogeomorphic forest dynamics, and on the role of combined stressors influencing forest retreat. Integrating simulation models of forest structure under changing physical (e.g. due to sea-level change) and ecological drivers with hydrodynamic attenuation models will allow for better projections of long-term natural coastal protection. 相似文献
97.
Daisy Sproviero Stella Gagliardi Susanna Zucca Maddalena Arigoni Marta Giannini Maria Garofalo Martina Olivero Michela DellOrco Orietta Pansarasa Stefano Bernuzzi Micol Avenali Matteo Cotta Ramusino Luca Diamanti Brigida Minafra Giulia Perini Roberta Zangaglia Alfredo Costa Mauro Ceroni Nora I. Perrone-Bizzozero Raffaele A. Calogero Cristina Cereda 《International journal of molecular sciences》2021,22(5)
Identifying biomarkers is essential for early diagnosis of neurodegenerative diseases (NDs). Large (LEVs) and small extracellular vesicles (SEVs) are extracellular vesicles (EVs) of different sizes and biological functions transported in blood and they may be valid biomarkers for NDs. The aim of our study was to investigate common and different miRNA signatures in plasma derived LEVs and SEVs of Alzheimer’s disease (AD), Parkinson’s disease (PD), Amyotrophic Lateral Sclerosis (ALS) and Fronto-Temporal Dementia (FTD) patients. LEVs and SEVs were isolated from plasma of patients and healthy volunteers (CTR) by filtration and differential centrifugation and RNA was extracted. Small RNAs libraries were carried out by Next Generation Sequencing (NGS). MiRNAs discriminate all NDs diseases from CTRs and they can provide a signature for each NDs. Common enriched pathways for SEVs were instead linked to ubiquitin mediated proteolysis and Toll-like receptor signaling pathways and for LEVs to neurotrophin signaling and Glycosphingolipid biosynthesis pathway. LEVs and SEVs are involved in different pathways and this might give a specificity to their role in the spreading of the disease. The study of common and different miRNAs transported by LEVs and SEVs can be of great interest for biomarker discovery and for pathogenesis studies in neurodegeneration. 相似文献
98.
99.
Mono-material in the manufacturing of oil-based plastic bottles has been so far not considered because of the poor flexibility of polyethylene terephthalate (PET). The undercuts of PET caps (i.e., the threads of the screw caps) would be torn-off during the ejection step of the injection/compression molding processes that are commonly used to fabricate them. In this respect, the present work deals with the design and development of innovative biodegradable polyester-based blends with high flexibility, intended for the manufacturing of screw-cap, being this element the most critical in the implementation of the complete bottle. The blend is based on polylactic acid and it is tailored for injection molding of tamper-evident screw plastic caps by the addition of another biodegradable polyester, that is, polybutylene adipate-co-terephthalate. The effect of the addition of a barrier agent, polyvinyl alcohol, on the overall behavior of the blends was also studied in the perspective of the implementation of caps featuring barrier properties against water vapor and oxygen. The same material could be, however, easily tailored for the fabrication of the bottle body and printed label to get to the mono-material bottle. Twin-screw corotating extrusion of the compound, injection molding of the plastic material for the fabrication of the screw caps, and evaluation of the thermophysical and mechanical properties of the screw caps are hereinafter discussed. The biodegradable polyester-based blends are found to be suitable for injection molding of the tamper-evident screw caps, exhibiting adequate flexibility during ejection from the mold. The screw caps can also boast appreciable mechanical strength and impact resistance as well as good thermal stability. 相似文献