Magnetic and morphological characterization of Nd2Fe14B magnets with different quality grades at low temperature 5-300 K

An increasing number of cryogenic devices may benefit from the use of Nd2Fe14B permanent magnets. However, it is necessary to precisely know their behavior because magnetization varies significantly due to Spin Reorientation Transition. In this work, magnetic and morphological characterization of Nd2Fe14B commercial polycrystalline magnets with different quality grades from 5 to 300 K is provided. A set of magnets ranging from N35 to N52 quality have been analyzed. Mean grain dimension as well as material composition elements are provided. Higher quality magnets show smaller mean grain dimensions. Regarding cryogenic temperatures, the well know spin transition effect appears in all the magnets as expected, however, the transition temperature occurs at different temperatures in a range from 112 to 120 K which is lower than those obtained for single crystal samples. Moreover, the relative variation of the remanence from 300 to 5 K is lower than 4% while the maximum expected variation is in average 11%. As extra information, the same analyzes are provided for additional quality grades N40M, N40S, N40SH and N40UH.The research leading to these results has received funding from the European Community's Seventh Framework Programme ([FP7/2007-2013]) under grant agreement n° 263014

VID22 counteracts G-quadruplex-induced genome instability

Genome instability is a condition characterized by the accumulation of genetic alterations and is a hallmark of cancer cells. To uncover new genes and cellular pathways affecting endogenous DNA damage and genome integrity, we exploited a Synthetic Genetic Array (SGA)-based screen in yeast. Among the positive genes, we identified VID22, reported to be involved in DNA double-strand break repair. vid22Δ cells exhibit increased levels of endogenous DNA damage, chronic DNA damage response activation and accumulate DNA aberrations in sequences displaying high probabilities of forming G-quadruplexes (G4-DNA). If not resolved, these DNA secondary structures can block the progression of both DNA and RNA polymerases and correlate with chromosome fragile sites. Vid22 binds to and protects DNA at G4-containing regions both in vitro and in vivo. Loss of VID22 causes an increase in gross chromosomal rearrangement (GCR) events dependent on G-quadruplex forming sequences. Moreover, the absence of Vid22 causes defects in the correct maintenance of G4-DNA rich elements, such as telomeres and mtDNA, and hypersensitivity to the G4-stabilizing ligand TMPyP4. We thus propose that Vid22 is directly involved in genome integrity maintenance as a novel regulator of G4 metabolism.Associazione Italiana per la Ricerca sul Cancro (AIRC) 15631, 21806MIUR PRIN 2015- 2015SJLMB9, PRIN 2017-2017KSZZJW, PRIN2017-2017Z55KCMinisterio de Economía y Competitividad BFU2016- 75058-PCanadian Institutes of Health Research FDN-15991

VID22 counteracts G-quadruplex-induced genome instability

Genome instability is a condition characterized by the accumulation of genetic alterations and is a hallmark of cancer cells. To uncover new genes and cellular pathways affecting endogenous DNA damage and genome integrity, we exploited a Synthetic Genetic Array (SGA)-based screen in yeast. Among the positive genes, we identified VID22, reported to be involved in DNA double-strand break repair. vid22Δ cells exhibit increased levels of endogenous DNA damage, chronic DNA damage response activation and accumulate DNA aberrations in sequences displaying high probabilities of forming G-quadruplexes (G4-DNA). If not resolved, these DNA secondary structures can block the progression of both DNA and RNA polymerases and correlate with chromosome fragile sites. Vid22 binds to and protects DNA at G4-containing regions both in vitro and in vivo. Loss of VID22 causes an increase in gross chromosomal rearrangement (GCR) events dependent on G-quadruplex forming sequences. Moreover, the absence of Vid22 causes defects in the correct maintenance of G4-DNA rich elements, such as telomeres and mtDNA, and hypersensitivity to the G4-stabilizing ligand TMPyP4. We thus propose that Vid22 is directly involved in genome integrity maintenance as a novel regulator of G4 metabolism.Associazione Italiana per la Ricerca sul Cancro (AIRC) [15631, 21806 to M.M.F.]; MIUR [PRIN 2015-2015SJLMB9; PRIN 2017-2017KSZZJW to M.M.F.]; Telethon [GGP15227 to M.M.F.]; F.L. was supported by the University of Milano: ‘‘Piano di Sviluppo dell’Ateneo per la Ricerca. Linea B: Supporto per i Giovani Ricercatori’’; M.C.B. was supported by Fondazione Veronesi; Research at the laboratory of A.A. was funded by the Spanish Ministry of Economy and Competitiveness [BFU2016-75058-P]; B.G.G. was funded by the Spanish Association Against Cancer; MIUR [PRIN2017-2017Z55KC to T.B.]; M.C., D.S.H. are supported by MIUR [PRIN 2017] and CNRbiomics [PIR01_00017]; H2020 Projects ELIXIR-EXCELERATE, EOSC-Life, EOSC-Pillar and Elixir-IIB; G.W.B. was supported by the Canadian Institutes of Health Research[FDN-159913]. Funding for open access charge: Associazione Italiana per la Ricerca sul Cancro (AIRC) [21806]

MIL-100(Fe) MOF as an emerging sulfur-host cathode for ultra long-cycle Metal-Sulfur batteries

Metal–Sulfur (Li/Na–S) battery technology is considered one of the most promising energy storage systems because of its high specific capacity of 1675 mA h/g, attributed to sulfur. However, the rapid capacity degradation, mainly caused by metallic polysulfide dissolution, remains a significant challenge prior to practical applications. This work demonstrates for the first time that a Fe-based metal organic framework (MIL-100(Fe)) can remarkably stabilize the electrochemical behavior of sulfur-cathodes in Metal-S cells during prolonged cycling. The chemical and morphological properties of MIL-100(Fe) and, especially conjugated with their textural characteristics, can help immobilize lithium/sodium polysulfides within the highly microporous cathode structure. Capacity loss per cycle is 0.044 mA h after 3000 cycles at 2C in Li–S cells. This behavior is confirmed when the MOF-based cathode is studied in RT Na–S batteries, managing to stabilize the capacity with a loss of less than 0.08 % during 2000 cycles at 0.1 C-rate. The excellent performance can be attributed to the synergistic effects of the highly microporous structure of MOF-100(Fe), which provide an ideal matrix to confine polysulfides, and the presence of Fe(III) active centers that provide chemical affinities to sulfur and polysulfides. These factors contribute to the excellent cycling performance of the S@MIL-100(Fe) composite in Metal-Sulfur batteries

Sensing properties, energy transfer mechanism and tuneable particle size processing of luminescent two-dimensional rare earth coordination networks

A new isostructural family of layered coordination networks (CNs) based on rare earth elements and mixed ligands was hydrothermally synthesized and fully characterized. The set of compounds with the general formula [REE(Salicylate)(Succinate)(HO)] (with REE = Ho or Y) belong to the monoclinic P2/c space group. Top-down methods were implemented in order to obtain nano-sized CN particles for potential application in thin film fabrication. The solid state photoluminescence (SSPL) of the Eu, Tb and Eu/Tb doped samples was explored in terms of excitation/emission spectra, lifetime values and quantification of light emission by the CIE chromaticity calculation. Measurement of the triplet state energy of the ligand at low temperature was carried out by analysing the SSPL of the Y-based compound; energy transfer pathways were studied. According to the high performance of the Tb-doped compound as a green emitter, thermal and chemical sensing assays were carried out.This work was supported by the Consejo Nacional de Investigaciones Científicas y Técnicas (PIP- CONICET 11220150100820CO) and PROICO 2-2016 (UNSL-INTEQUI). R. V. D. thanks the Hercules Foundation (project AUGE/09/024 “Advanced Luminescence Setup”) for funding. A. A. G. acknowledges a PhD CONICET fellowship, A. M. K. acknowledges Ghent University's Special Research Fund (BOF) for a Postdoctoral Mandate (project BOF15/PDO/091). G. E. N., O. J. F. and M. C. B. are members of CIC-CONICET. G. E. G. acknowledges a postdoctoral CONICET fellowship