A metal-organic open-framework with an unprecedented (6,3)-helical topology, large channels and mixed ferro-and antiferromagnetic interactions has been synthesized using a three-connecting tricarboxylic polychlorotriphenylmethyl radical and Co(II) ions.Rapid development in the self-assembly of transition metal ions and multitopic organic ligands has yielded a wide variety of one-, two-and three-dimensional metal-organic architectures that have specific properties.1 For instance, in the field of porous metalorganic materials, the endless versatility of molecular chemistry to design new polytopic ligands has become an excellent tool to obtain open-framework structures 2 with different topologies 3 and surprising porosity properties. 4 Furthermore, along with the typical applications of porous solids as molecular sieves, sensors, ion-exchangers and catalysts, the recent construction of openframeworks from paramagnetic transition metal ions also opens the possibility to design porous materials with additional electrical, 5 optical 6 or magnetic properties. Among them, attainment of magnetic metal-organic porous solids has attracted considerable efforts in the last few years because of their potential applications as magnetic sensors and/or low-density magnetic materials. 7,8 So far, different polytopic ligands that allow not only control of pore sizes but also favour magnetic exchange interactions have been used. 7 In our group, we recently described a new strategy for the preparation of nanoporous materials with enhanced magnetic properties consisting of the use of purely organic radicals as ''spacer'' paramagnetic ligands.9 Thus, we designed and synthesized a polytopic open-shell perchlorinated triphenylmethyl radical with three carboxylic groups (PTMTC, Fig. 1a). 10 In terms of topology, PTMTC is a trigonal bridging ligand that can be considered an expanded version of the well-known trimesic acid.Moreover, the presence of a rigid structure with bulky chlorine atoms, in addition to providing high thermal and chemical stability, would prevent interpenetration phenomena. 4 (EtOH)] formed by the self-assembly of 3-connected bridging PTMTC radicals and a transition metal ion with large magnetic anisotropy like Co(II). This is, to our knowledge, the first example of a nanochannel-like structure that in addition to exhibiting an unusual (6,3)-helical coordination network shows mixed ferro-and antiferromagnetic interactions between the Co(II) ions and PTMTC radicals.Red needle-like crystals of MOROF-3 were obtained by slow diffusion of an ethanol solution of pyridine onto a solution of Co(ClO 4 ) 2 ?6H 2 O and PTMTC in ethanol and water.{ Singlecrystal X-ray analysis of MOROF-3 reveals a three-dimensional framework built from seven different crystallographic octahedral Co(II) units, which slightly differ in their coordination sphere (Fig. 1b)

We report experiments on magnetic avalanches in the intermetallic compound Gd 5 Ge 4 . Kinetics of the avalanches have been studied and compared with the theory of magnetic deflagration. We show that the data fit well into the theoretical framework of deflagration. This adds Gd 5 Ge 4 to the growing family of materials ͑that now includes molecular magnets and manganites͒ which exhibit this phenomenon. The "burning" of the metastable magnetic phase involves a magnetostructural transition alongside the reordering of spins.

We report here a study on the environmental dependence of the occurrence, at low temperature, of ultra-sharp field induced avalanches in phase separated manganites. Despite the high reproducibility of avalanches, it has already been observed that the critical fields shift with the magnetic field sweep rate and that different sample sizes lead to different ignition fields for the avalanches. Critical growing rates have been suggested to describe the avalanche ignition though the role of thermal coupling has hardly been considered. We qualitatively analyze here a set of experimental data on avalanches in manganites and discuss the role of thermal coupling as a key parameter of the instability in a dynamical system.

The co-existence of colossal positive and negative magnetoresistance has been observed in a perovskite-type material Nd 0.67Ca0.33MnO3. The hysteretic behavior of resistivity in temperature and magnetic field suggests the existence of phase transition. Positive magnetoresistance (positive-MR = [ρ(B) − ρ(0)]/ρ(0)) up to 10000% was observed below insulatormetal transition temperature, T I-M ∼ 45 K, accompanied by a negative magnetoresistance (negative-MR) with further increasing magnetic field. The positive-MR may be attributed to the field-induced carrier localization (CL), whereas the very large negative-MR is believed to be due to the field-induced collapse of charge ordering.

Dexamethasone and tocilizumab have been associated with reduction in mortality, however, the beneficial effect is not for all patients and the impact on viral replication is not well defined. We hypostatized that C-reactive protein (CRP) could help in the identification of patients requiring anti-inflammatory therapy. Patients admitted for > 48 h in our hospital for a confirmed or suspected infection by SARS-CoV-2 from February 2020 to February 2021 were retrospectively evaluated. The primary outcome was mortality at 30 days. Demographics and the most relevant variables related with the outcome were included. CRP was stratified by percentiles. Univariate and multivariate analysis were performed. A total of 3218 patients were included with a median (IQR) age of 66 (74–78) years and 58.9% were males. The rate of intensive care unit admission was 24.4% and the 30-day mortality rate was 11.8%. Within the first 5 days from admission, 1018 (31.7%) patients received dexamethasone and 549 tocilizumab (17.1%). The crude analysis showed a mortality reduction in patients receiving dexamethasone when CRP was > 13.75 mg/dL and > 3.5 mg/dL for those receiving tocilizumab. Multivariate analysis identified the interaction of CRP > 13.75 mg/dL with dexamethasone (OR 0.57; CI 95% 0.37–0.89, P = 0014) and CRP > 3.5 mg/dL with tocilizumab (0.65; CI95%:0.44–0.95, P = 0.029) as independent predictors of mortality. Our results suggest that dexamethasone and tocilizumab are associated with a reduction in mortality when prescribed to patients with a certain inflammatory activity assessed by C-reactive protein.