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排序方式: 共有849条查询结果,搜索用时 15 毫秒
841.
Valeria Orlando Silvia Di Tommaso Viola Alesi Sara Loddo Silvia Genovese Giorgia Catino Licia Martucci Maria Cristina Roberti Marina Trivisano Maria Lisa Dentici Nicola Specchio Bruno Dallapiccola Alessandro Ferretti Antonio Novelli 《International journal of molecular sciences》2022,23(21)
Complex genomic rearrangements (CGRs) are structural variants arising from two or more chromosomal breaks, which are challenging to characterize by conventional or molecular cytogenetic analysis (karyotype and FISH). The integrated approach of standard and genomic techniques, including optical genome mapping (OGM) and genome sequencing, is crucial for disclosing and characterizing cryptic chromosomal rearrangements at high resolutions. We report on a patient with a complex developmental and epileptic encephalopathy in which karyotype analysis showed a de novo balanced translocation involving the long arms of chromosomes 2 and 18. Microarray analysis detected a 194 Kb microdeletion at 2q24.3 involving the SCN2A gene, which was considered the likely translocation breakpoint on chromosome 2. However, OGM redefined the translocation breakpoints by disclosing a paracentric inversion at 2q24.3 disrupting SCN1A. This combined genomic high-resolution approach allowed a fine characterization of the CGR, which involves two different chromosomes with four breakpoints. The patient’s phenotype resulted from the concomitant loss of function of SCN1A and SCN2A. 相似文献
842.
Chuchu Chen Tong Zhou Zhangmin Wan Zhaoyang Xu Yongcan Jin Dagang Li Orlando J. Rojas 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(38):2301472
The combination of optical transparency and mechanical strength is a highly desirable attribute of wood-based glazing materials. However, such properties are typically obtained by impregnation of the highly anisotropic wood with index-matching fossil-based polymers. In addition, the presence of hydrophilic cellulose leads to a limited water resistance. Herein, this work reports on an adhesive-free lamination that uses oxidation and densification to produce transparent all-biobased glazes. The latter are produced from multilayered structures, free of adhesives or filling polymers, simultaneously displaying high optical clarity and mechanical strength, in both dry and wet conditions. Specifically, high values of optical transmittance (≈85.4%), clarity (≈20% with low haze) at a thickness of ≈0.3 mm, and highly isotropic mechanical strength and water resistance (wet strength of ≈128.25 MPa) are obtained for insulative glazes exhibiting low thermal conductivity (0.27 W m−1 K−1, almost four times lower than glass). The proposed strategy results in materials that are systematically tested, with the leading effects of self-adhesion induced by oxidation rationalized by ab initio molecular dynamics simulation. Overall, this work demonstrates wood-derived materials as promising solutions for energy-efficient and sustainable glazing applications. 相似文献
843.
Maria Letizia Corradini Gianluca Ippoliti Giuseppe Orlando 《Asian journal of control》2023,25(5):3384-3394
In this paper, the control of a variable-speed variable-pitch wind turbine in the whole wind speed range is addressed, without any feedback measurement of wind speed. In addition to an aerodynamic torque observer able to ensure the tracking of the maximum delivered power in the partial-load region, a novel wind speed observer is proposed for power regulation in the full-load region, along with a sliding surface ensuring finite-time set-point stabilization of the speed tracking error. The proposed control solution has been validated on the National Renewable Energy Laboratory 5-MW three-blade wind turbine model using the recognized high-fidelity simulation tool FAST. 相似文献
844.
Yi Lu Milad Kamkar Shasha Guo Xun Niu Zhangmin Wan Junhua Xu Xiaoya Su Yimin Fan Long Bai Orlando J. Rojas 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(39):2370315
Non-equilibrium multiphase systems are formed by mixing two immiscible nanoparticle dispersions, leading to bicontinuous emulsions that template cryogels with interconnected, tortuous channels. Herein, a renewable, rod-like biocolloid (chitin nanocrystals, ChNC) is used to kinetically arrest bicontinuous morphologies. Specifically, it is found that ChNC stabilizes intra-phase jammed bicontinuous systems at an ultra-low particle concentration (as low as 0.6 wt.%), leading to tailorable morphologies. The synergistic effects of ChNC high aspect ratio, intrinsic stiffness, and interparticle interactions produce hydrogelation and, upon drying, lead to open channels bearing dual characteristic sizes, suitably integrated into robust bicontinuous ultra-lightweight solids. Overall, it demonstrates the successful formation of ChNC-jammed bicontinuous emulsions and a facile emulsion templating route to synthesize chitin cryogels that form unique super-macroporous networks. 相似文献
845.
Bruno D. Mattos Noora Jäntti Sergei Khakalo Ya Zhu Arttu Miettinen Joni Parkkonen Alexey Khakalo Orlando J. Rojas Mariko Ago 《Advanced functional materials》2023,33(45):2304867
A renewable source of carbon black is introduced by the processing of lignin from agro-forestry residues. Lignin side streams are converted into spherical particles by direct aerosolization followed by carbonization. The obtained submicron black carbon is combined with cellulose nanofibers, which act as a binder and rheology modifier, resulting in a new type of colloidal bioink. The bioinks are tested in handwriting and direct ink writing. After consolidation, the black bioinks display total light reflectance (%R) at least three times lower than commercial black inks (reduction from 12 to 4%R). A loading of up to 20% of nanofibers positively affects the cohesion of the dried bioink (1 to 16 MPa), with no significant reduction in light reflectance. This is a result of the superstructuring of the ink components, which disrupts particle packing, intensifies colloidal interactions, introduces light absorption, and non-reflective multiple scattering. 相似文献
846.
Alex Zea Guillem Valero Andrea‐NekaneR. Alba Albert Moyano Ramon Rios 《Advanced Synthesis \u0026amp; Catalysis》2010,352(7):1102-1106
For the first time, the addition of anthrones to maleimides catalyzed by bifunctional thiourea catalysts is reported. The thiourea moiety is able to activate the maleimide and the tertiary amine deprotonates the anthrone, furnishing the final Diels–Alder or Michael adducts in excellent yields and enantioselectivities. 相似文献
847.
The relationship between textile architecture and the damage sequence under tensile loading has been investigated experimentally for a composite material reinforced with a noncrimp glass‐fiber textile of configuration [0°, +45°, 90°, −45°] stacking sequence based on epoxy resin matrix cured with high‐temperature hardener. The system chosen for this work consists of a bifunctional epoxy, diglycidyl ether of bisphenol A, cured with a tetrafunctional amine, diaminodiphenyl sulfone (DDS). This system ensures to obtain a rigid material with excellent mechanical properties in order to observe, analyze, and identify the process and progress of the generated damage and the failure mechanism which leads to the materials fracture. The properties have been studied for each ply direction at 0°, +45°, 90°, and −45° in order to make a comparative assessment of the influence of the polyester (PES) yarns in zig‐zag and unidirectional geometry, that hold together the four plies in the textile, in the composite damage generation. The laminates were uniaxially tensile loaded until final fracture occurred. It was found that PES threads have an effect on cracking progression depending on the textile orientation. POLYM. COMPOS., 2009. © 2009 Society of Plastics Engineers 相似文献
848.
This paper describes COLTHPF, a run-time support specifically designed for the co-ordination of concurrent and communicating HPF tasks. COLTHPF is implemented on top of MPI and requires only small changes to the run-time support of the HPF compiler used. Although the COLTHPF API can be used directly by programmers to write applications as a flat collection of interacting data-parallel tasks, we believe that it can be used more productively through a compiler of a simple high-level co-ordination language which facilitates programmers in structuring a set of data-parallel HPF tasks according to common forms of task-parallelism. The paper outlines design and implementation issues, and discusses the main differences from other approaches to exploiting task parallelism in the HPF framework. We show how COLTHPF can be used to implement common forms of parallelism, e.g. pipeline and processor farms, and we present experimental results regarding both synthetic micro-benchmarks and sample applications. The experiments were conducted on an SGI/Cray T3E using Adaptor, a public domain HPF compiler. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
849.
Carla Orlando Dr. Mario Prejanò Prof. Nino Russo Prof. Dr. Tiziana Marino 《Chembiochem : a European journal of chemical biology》2023,24(20):e202300412
Enzyme FAST-PETase, recently obtained by a machine learning approach, can depolymerize poly(ethylene terephthalate) (PET), a synthetic resin employed in plastics and in clothing fibers. Therefore it represents a promising solution for the recycling of PET-based materials. In this study, a model of PET was adopted to describe the substrate, and all-atoms classical molecular dynamics (MD) simulations on apo- and substrate-bound FAST-PETase were carried out at 30 and 50 °C to provide atomistic details on the binding step of the catalytic cycle. Comparative analysis shed light on the interactions occurring between the FAST-PETase and 4PET at 50 °C, the optimal working conditions of the enzyme. Pre-organization of the enzyme active and binding sites has been highlighted, while MD simulations of FAST-PETase:4PET pointed out the occurrence of solvent-inaccessible conformations of the substrate promoted by the enzyme. Indeed, neither of these conformations was observed during MD simulations of the substrate alone in solution performed at 30, 50 and 150 °C. The analysis led us to propose that, at 50 °C, the FAST-PETase is pre-organized to bind the PET and that the interactions occurring in the binding site can promote a more reactive conformation of PET substrate, thus enhancing the catalytic activity of the enzyme. 相似文献