Histone demethylase IBM1-mediated meiocyte gene expression ensures meiotic chromosome synapsis and recombination

Histone methylation and demethylation play important roles in plant growth and development, but the involvement of histone demethylation during meiosis is poorly understood. Here we show that disruption of Arabidopsis thaliana INCREASE IN BONSAI METHYLATION 1 (IBM1) causes incomplete synapsis, chromosome entanglement and reduction of recombination during meiosis, leading to sterility. Interestingly, these ibm1 meiotic defects are rescued by mutations in either SUVH4/KYP or CMT3. Using transcriptomic analyses we show that mutation of IBM1 down-regulates thousands of genes expressed in meiocytes, and that expression of about 38% of these genes are restored to wild type levels in ibm1 cmt3 double mutants. Changes in the expression of 437 of these, including the ARABIDOPSIS MEI2-LIKE AML3-5 genes, are correlated with a significant reduction of gene body CHG methylation. Consistently, the aml3 aml4 aml5 triple have defects in synapsis and chromosome entanglement similar to ibm1. Genetic analysis shows that aml3 aml4 aml5 ibm1 quadruple mutants resembles the ibm1 single mutant. Strikingly, over expression of AML5 in ibm1 can partially rescue the ibm1 meiotic defects. Taken together, our results demonstrate that histone demethylase IBM1 is required for meiosis likely via coordinated regulation of meiocyte gene expression during meiosis

Circulating extracellular vesicles are associated with the clinical outcomes of sepsis

IntroductionSepsis is associated with endothelial cell (EC) dysfunction, increased vascular permeability and organ injury, which may lead to mortality, acute respiratory distress syndrome (ARDS) and acute renal failure (ARF). There are no reliable biomarkers to predict these sepsis complications at present. Recent evidence suggests that circulating extracellular vesicles (EVs) and their content caspase-1 and miR-126 may play a critical role in modulating vascular injury in sepsis; however, the association between circulating EVs and sepsis outcomes remains largely unknown.MethodsWe obtained plasma samples from septic patients (n=96) within 24 hours of hospital admission and from healthy controls (n=45). Total, monocyte- or EC-derived EVs were isolated from the plasma samples. Transendothelial electrical resistance (TEER) was used as an indicator of EC dysfunction. Caspase-1 activity in EVs was detected and their association with sepsis outcomes including mortality, ARDS and ARF was analyzed. In another set of experiments, total EVs were isolated from plasma samples of 12 septic patients and 12 non-septic critical illness controls on days 1, and 3 after hospital admission. RNAs were isolated from these EVs and Next-generation sequencing was performed. The association between miR-126 levels and sepsis outcomes such as mortality, ARDS and ARF was analyzed.ResultsSeptic patients with circulating EVs that induced EC injury (lower transendothelial electrical resistance) were more likely to experience ARDS (p<0.05). Higher caspase-1 activity in total EVs, monocyte- or EC-derived EVs was significantly associated with the development of ARDS (p<0.05). MiR-126-3p levels in EC EVs were significantly decreased in ARDS patients compared with healthy controls (p<0.05). Moreover, a decline in miR-126-5p levels from day 1 to day 3 was associated with increased mortality, ARDS and ARF; while decline in miR-126-3p levels from day 1 to day 3 was associated with ARDS development.ConclusionsEnhanced caspase-1 activity and declining miR-126 levels in circulating EVs are associated with sepsis-related organ failure and mortality. Extracellular vesicular contents may serve as novel prognostic biomarkers and/or targets for future therapeutic approaches in sepsis

Expression and Localization of Mitochondrial Ferritin mRNA in Alzheimer's Disease Cerebral Cortex

Mitochondrial ferritin (MtF) has been identified as a novel ferritin encoded by an intron-lacking gene with specific mitochondrial localization located on chromosome 5q23.1. MtF has been associated with neurodegenerative disorders such as Friedreich ataxia and restless leg syndrome. However, little information is available about MtF in Alzheimer's disease (AD). In this study, therefore, we investigated the expression and localization of MtF messenger RNA (mRNA) in the cerebral cortex of AD and control cases using real-time polymerase chain reaction (PCR) as well as in situ hybridization histochemistry. We also examined protein expression using western-blot assay. In addition, we used in vitro methods to further explore the effect of oxidative stress and β-amyloid peptide (Aβ) on MtF expression. To do this we examined MtF mRNA and protein expression changes in the human neuroblastoma cell line, IMR-32, after treatment with Aβ, H2O2, or both. The neuroprotective effect of MtF on oxidative stress induced by H2O2 was measured by MTT assay. The in situ hybridization studies revealed that MtF mRNA was detected mainly in neurons to a lesser degree in glial cells in the cerebral cortex. The staining intensity and the number of positive cells were increased in the cerebral cortex of AD patients. Real-time PCR and western-blot confirmed that MtF expression levels in the cerebral cortex were significantly higher in AD cases than that in control cases at both the mRNA and the protein level. Cell culture experiments demonstrated that the expression of both MtF mRNA and protein were increased by treatment with H2O2 or a combination of Aβ and H2O2, but not with Aβ alone. Finally, MtF expression showed a significant neuroprotective effect against H2O2-induced oxidative stress (p<0.05). The present study suggests that MtF is involved in the pathology of AD and may play a neuroprotective role against oxidative stress

A study on containerization in continuous integration and testing pipeline in TETRA dispatcher environment

Containers have become a widely accepted platform to develop, ship, and run applications. The popularity is derived from their increased portability, great efficiency, and small computational overhead. Besides, agile methodologies, such as test automation and continuous integration, are playing an essential role when developing containerized applications. In this thesis project, I studied how to implement containerization in a TETRA dispatcher environment, which is originally built on the platform of a virtual machine. First, I conducted a systematic literature review about some common terms and theories used in the thesis. Then I did some research on how to containerize the existing application, wrote an automation test and integrated the build and test processes into the continuous integration pipeline. The contribution of this thesis is to provide a guideline for containerization of existing applications in a TETRA dispatcher environment. The practical implementation is explained and is then followed by results and conclusions, which can be evaluated to improve the application performance. The developed solution turned out to be an effective approach to better the functionalities of the target application. It has been involved in the existing workflow seamlessly. Moreover, this is also an important step to the adoption of modern cloud architecture

R3c-type LnNiO3 (Ln = La, Ce, Nd, Pm, Gd, Tb, Dy, Ho, Er, Lu) half-metals with multiple Dirac cones: a potential class of advanced spintronic materials

In the past three years, Dirac half-metals (DHMs) have attracted considerable attention and become a high-profile topic in spintronics becuase of their excellent physical properties such as 100% spin polarization and massless Dirac fermions. Two-dimensional DHMs proposed recently have not yet been experimentally synthesized and thus remain theoretical. As a result, their characteristics cannot be experimentally confirmed. In addition, many theoretically predicted Dirac materials have only a single cone, resulting in a nonlinear electromagnetic response with insufficient intensity and inadequate transport carrier efficiency near the Fermi level. Therefore, after several attempts, we have focused on a novel class of DHMs with multiple Dirac crossings to address the above limitations. In particular, we direct our attention to three-dimensional bulk materials. In this study, the discovery via first principles of an experimentally synthesized DHM LaNiO3 with many Dirac cones and complete spin polarization near the Fermi level is reported. It is also shown that the crystal structures of these materials are strongly correlated with their physical properties. The results indicate that many rhombohedral materials with the general formula LnNiO3 (Ln = La, Ce, Nd, Pm, Gd, Tb, Dy, Ho, Er, Lu) in the space group R 3 c are potential DHMs with multiple Dirac cones

Optimizing multi-user indoor sound communications with acoustic reconfigurable metasurfaces

Abstract Sound in indoor spaces forms a complex wavefield due to multiple scattering encountered by the sound. Indoor acoustic communication involving multiple sources and receivers thus inevitably suffers from cross-talks. Here, we demonstrate the isolation of acoustic communication channels in a room by wavefield shaping using acoustic reconfigurable metasurfaces (ARMs) controlled by optimization protocols based on communication theories. The ARMs have 200 electrically switchable units, each selectively offering 0 or π phase shifts in the reflected waves. The sound field is reshaped for maximal Shannon capacity and minimal cross-talk simultaneously. We demonstrate diverse acoustic functionalities over a spectrum much larger than the coherence bandwidth of the room, including multi-channel, multi-spectral channel isolations, and frequency-multiplexed acoustic communication. Our work shows that wavefield shaping in complex media can offer new strategies for future acoustic engineering

Degenerate line modes in the surface and bulk phonon spectra of orthorhombic NaMgF3perovskite

Degenerate bulk-line phonon modes have been widely reported in various crystal system types; however, degenerate surface-line phonon modes have only been reported in monoclinic crystal systems, such as SnIP with space group P 2 / c (No. 13). Herein, we propose that degenerate surface-line phonon modes can also emerge in solids with orthorhombic structures. Based on first-principle calculations and symmetry analysis, we propose that orthorhombic NaMgF3 fluoroperovskite with space group Pnma (No. 62) is a material candidate with degenerate line states in both the bulk phonon mode and the (010) surface phonon mode. We discovered four closed nodal loops (two type-I and two hybrid-type) on the ky = 0 plane in the bulk phonon mode, all of which coexisted with Dirac points on the Z-U and X-U paths. Moreover, we discovered symmetry-projected doubly degenerate nodal lines along the X ¯ - U ¯ surface path in the (010) surface phonon mode. The proposed degenerate surface-line phonons in NaMgF3 is quite clean and protected by symmetries, which will aid future experimental detection

L21 and XA ordering competition in titanium-based full-Heusler alloys

The site preference rule, i.e., that the atomic sites of transition-metal-elements X and Y are determined by the number of their valence electrons, has been widely used in the design of full-Heusler alloys X 2 YZ and also used to explain their properties. In this work, the most popular Ti 2 -based Heusler alloys are selected as targets to study the site preferences of their atoms by theoretical calculations. It is observed that most of them are likely to form the L2 1 -type structure instead of the XA one. The reason for the site preference is explained on the basis of the calculated charge density differences. We further prove that each alloy shows abruptly different spintronic properties, depending on its L2 1 -type or XA-type structures. This research can be regarded as a counterexample to the site preference rule and is instructive for the future design of full-Heusler alloy materials