Understanding the complex structural features and phase changes in Na2Mg2(SO4)3:a combined single crystal and variable temperature powder diffraction and Raman spectroscopy study

Sodium mixed metal sulphates have attracted considerable attention, both in terms of mineralogy and more recently due to interest in Na ion containing materials for battery applications. The phase, Na 2 Mg 2 (SO 4 ) 3 , has been previously reported to undergo a phase change to langbeinite at high temperatures, which is interesting given that usually the langbeinite structure is only adopted when large alkali metal ions, e.g. K, Cs, are present. Nevertheless the room temperature structure of this phase has remained elusive, and so in this work, we report a detailed structural study of this system. We show that room temperature Na 2 Mg 2 (SO 4 ) 3 can only be prepared by quenching from high temperature, with slow cooling leading to phase separation to give the previously unreported systems, Na 2 Mg(SO 4 ) 2 and Na 2 Mg 3 (SO 4 ) 4 . We report the structures of quenched Na 2 Mg 2 (SO 4 ) 3 (monoclinic, P2 1 ), as well as Na 2 Mg(SO 4 ) 2 (triclinic, P1¯) and Na 2 Mg 3 (SO 4 ) 4 (orthorhombic, Pbca), detailing their complex structural features. Furthermore, we report a study of the thermal evolution of quenched Na 2 Mg 2 (SO 4 ) 3 with temperature through variable temperature XRD and Raman studies, which shows a complex series of phase transitions, highlighting why this phase has proven so elusive to characterise previously, and illustrating the need for detailed characterisation of such sulphate systems

High CO2 permeability in supported molten-salt membranes with highly dense and aligned pores produced by directional solidification

Composite molten salt-ceramic membranes are promising devices for high-temperature CO2 separation. Intensive material properties impact on separation performance as do membrane geometry (thickness) and microstructure (pore volume fraction, size, connectivity, and tortuosity factor). Although controlling pore size is considered somewhat routine, achieving pore alignment and connectivity is still challenging. Here we report the production of the first gas separation membrane using a porous ceramic matrix obtained from a directionally-solidified magnesium-stabilised zirconia (MgSZ) - MgO fibrilar eutectic as the membrane support. MgO was removed from the parent material by acid-etching to create a porous matrix with highly aligned pores with diameters of similar to 1 mu m. X-ray nano-computed tomography of a central portion (similar to 32, 000 mu m(3)) of the support identified similar to 21% porosity, with all pores aligned within 10 degrees and similar to 76% percolating along the longest sampled length. Employing the matrix as a support for a carbonate molten salt, a high CO2 permeability of 1.41x10(-10) mol m(-1).s(-1).Pa-1 at 815 degrees C was achieved, among the highest reported for supported molten-carbonate membranes (typically 10(-12) to 10(-10) mol m(-1).s(-1).Pa-1 at similar temperatures). We suggest that the high permeability is attributable to the excellent pore characteristics resulting from directional solidification, namely a dense array of parallel, micron-scale pores connecting the feed and permeate sides of the membrane

Structural insights into the DNA recognition mechanism by the bacterial transcription factor PdxR

This is the final version. Available from Oxford University Press via the DOI in this record.Atomic coordinates and structure factors for the reported apo-PdxR crystal structure have been deposited with the RCSB Protein Data Bank (PDB) under accession number 7PQ9. The cryo-EM maps of the holo-PdxR–DNA complex in the open, half-closed, and closed (C1 and C2 symmetry) conformation and the relative coordinates generated and analysed in the current study have been deposited in the Electron Microscopy Data Bank (EMDB) and in the PDB under accession code EMD-14960 (PDB 7ZTH), EMD-14778 (PDB 7ZLA), EMD-14852 (PDB 7ZPA) and EMD-14801 (PDB 7ZN5), respectively.Specificity in protein-DNA recognition arises from the synergy of several factors that stem from the structural and chemical signatures encoded within the targeted DNA molecule. Here, we deciphered the nature of the interactions driving DNA recognition and binding by the bacterial transcription factor PdxR, a member of the MocR family responsible for the regulation of pyridoxal 5'-phosphate (PLP) biosynthesis. Single particle cryo-EM performed on the PLP-PdxR bound to its target DNA enabled the isolation of three conformers of the complex, which may be considered as snapshots of the binding process. Moreover, the resolution of an apo-PdxR crystallographic structure provided a detailed description of the transition of the effector domain to the holo-PdxR form triggered by the binding of the PLP effector molecule. Binding analyses of mutated DNA sequences using both wild type and PdxR variants revealed a central role of electrostatic interactions and of the intrinsic asymmetric bending of the DNA in allosterically guiding the holo-PdxR-DNA recognition process, from the first encounter through the fully bound state. Our results detail the structure and dynamics of the PdxR-DNA complex, clarifying the mechanism governing the DNA-binding mode of the holo-PdxR and the regulation features of the MocR family of transcription factors.Italian MIUR-PRIN 2020POR FESR Lazio 2014–2020Sapienza University of RomeDefence Science and Technology Laboratory (DSTL)Istituto Pasteur Italia – Fondazione Cenci Bolognett

Prenatal Immune Challenge Is an Environmental Risk Factor for Brain and Behavior Change Relevant to Schizophrenia: Evidence from MRI in a Mouse Model

Objectives: Maternal infection during pregnancy increases risk of severe neuropsychiatric disorders, including schizophrenia and autism, in the offspring. The most consistent brain structural abnormality in patients with schizophrenia is enlarged lateral ventricles. However, it is unknown whether the aetiology of ventriculomegaly in schizophrenia involves prenatal infectious processes. The present experiments tested the hypothesis that there is a causal relationship between prenatal immune challenge and emergence of ventricular abnormalities relevant to schizophrenia in adulthood. Method: We used an established mouse model of maternal immune activation (MIA) by the viral mimic Polyl:C administered in early (day 9) or late (day 17) gestation. Automated voxel-based morphometry mapped cerebrospinal fluid across the whole brain of adult offspring and the results were validated by manual region-of-interest tracing of the lateral ventricles. Parallel behavioral testing determined the existence of schizophrenia-related sensorimotor gating abnormalities. Results: Polyl:C-induced immune activation, in early but not late gestation, caused marked enlargement of lateral ventricles in adulthood, without affecting total white and grey matter volumes. This early exposure disrupted sensorimotor gating, in the form of prepulse inhibition. Identical immune challenge in late gestation resulted in significant expansion of 4th ventricle volume but did not disrupt sensorimotor gating. Conclusions: Our results provide the first experimental evidence that prenatal immune activation is an environmental risk factor for adult ventricular enlargement relevant to schizophrenia. The data indicate immune-associated environmental insults targeting early foetal development may have more extensive neurodevelopmental impact than identical insults in late prenatal life. © 2009 Li et al.published_or_final_versio

White matter disturbances in major depressive disorder : a coordinated analysis across 20 international cohorts in the ENIGMA MDD working group

Altres ajuts: The ENIGMA-Major Depressive Disorder working group gratefully acknowledges support from the NIH Big Data to Knowledge (BD2K) award (U54 EB020403 to PMT) and NIH grant R01 MH116147 (PMT). LS is supported by an NHMRC MRFF Career Development Fellowship (APP1140764). We wish to acknowledge the patients and control subjects that have particiaped int the study. We thank Rosa Schirmer, Elke Schreiter, Reinhold Borschke and Ines Eidner for image acquisition and data preparation, and Anna Oliynyk for quality checks. We thank Dorothee P. Auer and F. Holsboer for initiation of the RUD study. We wish to acknowledge the patients and control subjects that have particiaped int the study. We thank Rosa Schirmer, Elke Schreiter, Reinhold Borschke and Ines Eidner for image acquisition and data preparation, and Anna Oliynyk for quality checks. We thank Dorothee P. Auer and F. Holsboer for initiation of the RUD study. NESDA: The infrastructure for the NESDA study (www.nesda.nl) is funded through the Geestkracht program of the Netherlands Organisation for Health Research and Development (Zon-Mw, grant number 10-000-1002) and is supported by participating universities (VU University Medical Center, GGZ inGeest, Arkin, Leiden University Medical Center, GGZ Rivierduinen, University Medical Center Groningen) and mental health care organizations, see www.nesda.nl. M-JvT was supported by a VENI grant (NWO grant number 016.156.077). UCSF: This work was supported by the Brain and Behavior Research Foundation (formerly NARSAD) to TTY; the National Institute of Mental Health (R01MH085734 to TTY; K01MH117442 to TCH) and by the American Foundation for Suicide Prevention (PDF-1-064-13) to TCH. Stanford: This work was supported by NIMH Grants R01MH59259 and R37101495 to IHG. MS is partially supported by an award funded by the Phyllis and Jerome Lyle Rappaport Foundation. Muenster: This work was funded by the German Research Foundation (SFB-TRR58, Projects C09 and Z02 to UD) and the Interdisciplinary Center for Clinical Research (IZKF) of the medical faculty of Münster (grant Dan3/012/17 to UD). Marburg: This work was funded by the German Research Foundation (DFG, grant FOR2107 DA1151/5-1 and DA1151/5-2 to UD; KI 588/ 14-1, KI 588/14-2 to TK; KR 3822/7-1, KR 3822/7-2 to AK; JA 1890/ 7-1, JA 1890/7-2 to AJ). IMH-MDD: This work was supported by the National Healthcare Group Research Grant (SIG/15012) awarded to KS. Barcelona: This study was funded by two grants of the Fondo de Investigación Sanitaria from the Instituto de Salud Carlos III, by the Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM). The author is funded through 'Miguel Servet' research contract (CP16-0020), co-financed by the European Regional Development Fund (ERDF) (2016-2019). QTIM: We thank the twins and singleton siblings who gave generously of their time to participate in the QTIM study. We also thank the many research assistants, radiographers, and IT support staff for data acquisition and DNA sample preparation. This study was funded by White matter disturbances in major depressive disorder: a coordinated analysis across 20 international. . . 1521 the National Institute of Child Health & Human Development (RO1 HD050735); National Institute of Biomedical Imaging and Bioengineering (Award 1U54EB020403-01, Subaward 56929223); National Health and Medical Research Council, Australia (Project Grants 496682, 1009064). NIH ENIGMA-BD2K U54 EB020403 (Thompson); R01 MH117601 (Jahanshad/Schmaal). Magdeburg: M.L. and M.W. are funded by SFB 779. Bipolar Family Study: This study has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013). This paper reflects only the author's views and the European Union is not liable for any use that may be made of the information contained therein. This work was also supported by a Wellcome Trust Strategic Award (104036/Z/14/Z). Minnesota Adolescent Depression Study: The study was funded by the National Institute of Mental Health (K23MH090421), the National Alliance for Research on Schizophrenia and Depression, the University of Minnesota Graduate School, the Minnesota Medical Foundation, and the Biotechnology Research Center (P41 RR008079 to the Center for Magnetic Resonance Research), University of Minnesota, and the Deborah E. Powell Center for Women's Health Seed Grant, University of Minnesota. Dublin: This study was supported by Science Foundation Ireland through a Stokes Professorhip grant to TF. MPIP: The MPIP Sample comprises patients included in the Recurrent Unipolar Depression (RUD) Case-Control study at the clinic of the Max Planck Institute of Psychiatry, Munich, German. The RUD study was supported by GlaxoSmithKline.Alterations in white matter (WM) microstructure have been implicated in the pathophysiology of major depressive disorder (MDD). However, previous findings have been inconsistent, partially due to low statistical power and the heterogeneity of depression. In the largest multi-site study to date, we examined WM anisotropy and diffusivity in 1305 MDD patients and 1602 healthy controls (age range 12-88 years) from 20 samples worldwide, which included both adults and adolescents, within the MDD Working Group of the Enhancing Neuroimaging Genetics through Meta-Analysis (ENIGMA) consortium. Processing of diffusion tensor imaging (DTI) data and statistical analyses were harmonized across sites and effects were meta-analyzed across studies. We observed subtle, but widespread, lower fractional anisotropy (FA) in adult MDD patients compared with controls in 16 out of 25 WM tracts of interest (Cohen's d between 0.12 and 0.26). The largest differences were observed in the corpus callosum and corona radiata. Widespread higher radial diffusivity (RD) was also observed (all Cohen's d between 0.12 and 0.18). Findings appeared to be driven by patients with recurrent MDD and an adult age of onset of depression. White matter microstructural differences in a smaller sample of adolescent MDD patients and controls did not survive correction for multiple testing. In this coordinated and harmonized multisite DTI study, we showed subtle, but widespread differences in WM microstructure in adult MDD, which may suggest structural disconnectivity in MDD

The cytoskeleton in cell-autonomous immunity: structural determinants of host defence

Host cells use antimicrobial proteins, pathogen-restrictive compartmentalization and cell death in their defence against intracellular pathogens. Recent work has revealed that four components of the cytoskeleton — actin, microtubules, intermediate filaments and septins, which are well known for their roles in cell division, shape and movement — have important functions in innate immunity and cellular self-defence. Investigations using cellular and animal models have shown that these cytoskeletal proteins are crucial for sensing bacteria and for mobilizing effector mechanisms to eliminate them. In this Review, we highlight the emerging roles of the cytoskeleton as a structural determinant of cell-autonomous host defence

Testing a global standard for quantifying species recovery and assessing conservation impact

Recognizing the imperative to evaluate species recovery and conservation impact, in 2012 the International Union for Conservation of Nature (IUCN) called for development of a “Green List of Species” (now the IUCN Green Status of Species). A draft Green Status framework for assessing species’ progress toward recovery, published in 2018, proposed 2 separate but interlinked components: a standardized method (i.e., measurement against benchmarks of species’ viability, functionality, and preimpact distribution) to determine current species recovery status (herein species recovery score) and application of that method to estimate past and potential future impacts of conservation based on 4 metrics (conservation legacy, conservation dependence, conservation gain, and recovery potential). We tested the framework with 181 species representing diverse taxa, life histories, biomes, and IUCN Red List categories (extinction risk). Based on the observed distribution of species’ recovery scores, we propose the following species recovery categories: fully recovered, slightly depleted, moderately depleted, largely depleted, critically depleted, extinct in the wild, and indeterminate. Fifty-nine percent of tested species were considered largely or critically depleted. Although there was a negative relationship between extinction risk and species recovery score, variation was considerable. Some species in lower risk categories were assessed as farther from recovery than those at higher risk. This emphasizes that species recovery is conceptually different from extinction risk and reinforces the utility of the IUCN Green Status of Species to more fully understand species conservation status. Although extinction risk did not predict conservation legacy, conservation dependence, or conservation gain, it was positively correlated with recovery potential. Only 1.7% of tested species were categorized as zero across all 4 of these conservation impact metrics, indicating that conservation has, or will, play a role in improving or maintaining species status for the vast majority of these species. Based on our results, we devised an updated assessment framework that introduces the option of using a dynamic baseline to assess future impacts of conservation over the short term to avoid misleading results which were generated in a small number of cases, and redefines short term as 10 years to better align with conservation planning. These changes are reflected in the IUCN Green Status of Species Standard