In Situ Formation of Iodide Precursor for Perovskite Quantum Dots with Application in Efficient Solar Cells.

Perovskite quantum dots (PQDs) become a kind of competitive material for fabricating high-performance solar cells due to their solution processability and outstanding optoelectronic properties. However, the current synthesis method of PQDs is mostly based on the binary-precursor method, which results in a large deviation of the I/Pb input ratio in the reaction system from the stoichiometric ratio of PQDs. Herein, a ternary-precursor method with an iodide source self-filling ability is reported for the synthesis of the CsPbI3 PQDs with high optoelectronic properties. Systematically experimental characterizations and theoretical calculations are conducted to fundamentally understand the effects of the I/Pb input molar ratio on the crystallographic and optoelectronic properties of PQDs. The results reveal that increasing the I/Pb input molar ratio can obtain ideal cubic structure PQDs with iodine-rich surfaces, which can significantly reduce the surface defects of PQDs and realize high orientation of PQD solids, facilitating charge carrier transport in the PQD solids with diminished nonradiative recombination. Consequently, the PQD solar cells exhibit an impressive efficiency of 15.16%, which is largely improved compared with that of 12.83% for the control solar cell. This work provides a feasible strategy for synthesizing high-quality PQDs for high-performance optoelectronic devices.

Longitudinal mass loads of phthalate esters in sewage sludge and their association with public health and social measures for COVID-19 control in Beijing.

This study examines the concentrations and population-normalized mass loads (PNML) of five phthalate esters (PAEs) and four metabolites (mPAEs) in 390 sewage sludge samples collected from two municipal wastewater treatment plants in Beijing between July 2020 and June 2023, amidst the COVID-19 pandemic. Through GC/MS analysis, the compounds were simultaneously quantified, with peak concentrations in 2020. Bis(2-ethylhexyl) phthalate (DEHP) and mono(2-ethyl-5-oxohexyl) phthalate emerged as predominant PAE and mPAE congeners with concentrations of 78.7 µg/g dw and 259 µg/g dw, respectively. DEHP and monobenzyl phthalate had the highest median PNML among PAEs and mPAEs, respectively, at 128 µg/inhabitant/day and 798 µg/inhabitant/day. Linear regression models revealed a positive association between PNML of PAEs and five public health and social measures aimed at mitigating the COVID-19 pandemic. This research contributes to the expanding body of literature by emphasizing the role of wastewater-based epidemiology as a vital tool for monitoring community-level exposure to environmental contaminants.

Active Beam Steering Enabled by Photonic-Crystal Surface-Emitting Laser.

Emitting light toward on-demand directions is important for various optoelectronic applications, such as optical communication, displaying, and ranging. However, almost all existing directional emitters are assemblies of passive optical antennae and external light sources, which are usually bulky and fragile and show unendurable loss of light power. Here we theoretically propose and experimentally demonstrate a conceptual design of a directional emitter, by using a single surface-emitting laser source itself to achieve dynamically controlled beam steering. The laser is built on photonic crystals that operate near the band edges in the continuum. By shrinking laser sizes to tens-of-wavelength, the optical modes quantize in three-dimensional momentum space, and each of them directionally radiates toward the far-field. Further utilizing the luminescence spectrum shifting effect under current injection, we consecutively select a sequence of modes into lasing action and show the laser maintaining single-mode operation with line widths at a minimum of 1.8 MHz and an emitting power of ∼10 milliwatts, and we demonstrate fast beam steering across a range of 3.2° × 4° on a time scale of 500 ns. Our work proposes a method for on-chip active beam steering for the development of automotive, industrial, and robotic applications.

Remodeling Intestinal Microbiota Alleviates Severe Combined Hyperlipidemia-Induced Nonalcoholic Steatohepatitis and Atherosclerosis in LDLR-/- Hamsters.

Combined hyperlipidemia (CHL) manifests as elevated cholesterol and triglycerides, associated with fatty liver and cardiovascular diseases. Emerging evidence underscores the crucial role of the intestinal microbiota in metabolic disorders. However, the potential therapeutic viability of remodeling the intestinal microbiota in CHL remains uncertain. In this study, CHL was induced in low-density lipoprotein receptor-deficient (LDLR-/-) hamsters through an 8-week high-fat and high-cholesterol (HFHC) diet or a 4-month high-cholesterol (HC) diet. Placebo or antibiotics were administered through separate or cohousing approaches. Analysis through 16S rDNA sequencing revealed that intermittent antibiotic treatment and the cohousing approach effectively modulated the gut microbiota community without impacting its overall abundance in LDLR-/- hamsters exhibiting severe CHL. Antibiotic treatment mitigated HFHC diet-induced obesity, hyperglycemia, and hyperlipidemia, enhancing thermogenesis and alleviating nonalcoholic steatohepatitis (NASH), concurrently reducing atherosclerotic lesions in LDLR-/- hamsters. Metabolomic analysis revealed a favorable liver lipid metabolism profile. Increased levels of microbiota-derived metabolites, notably butyrate and glycylglycine, also ameliorated NASH and atherosclerosis in HFHC diet-fed LDLR-/- hamsters. Notably, antibiotics, butyrate, and glycylglycine treatment exhibited protective effects in LDLR-/- hamsters on an HC diet, aligning with outcomes observed in the HFHC diet scenario. Our findings highlight the efficacy of remodeling gut microbiota through antibiotic treatment and cohousing in improving obesity, NASH, and atherosclerosis associated with refractory CHL. Increased levels of beneficial microbiota-derived metabolites suggest a potential avenue for microbiome-mediated therapies in addressing CHL-associated diseases.

Band Engineering of Perovskite Quantum Dot Solids for High-Performance Solar Cells.

CsPbI3 perovskite quantum dot (PQD) shows high potential for next-generation photovoltaics due to their tunable surface chemistry, good solution-processability and unique photophysical properties. However, the remained long-chain ligand attached to the PQD surface significantly impedes the charge carrier transport within the PQD solids, thereby predominantly influencing the charge extraction of PQD solar cells (PQDSCs). Herein, a ligand-induced energy level modulation is reported for band engineering of PQD solids to improve the charge extraction of PQDSCs. Detailed theoretical calculations and systemic experimental studies are performed to comprehensively understand the photophysical properties of the PQD solids dominated by the surface ligands of PQDs. The results reveal that 4-nitrobenzenethiol and 4-methoxybenzenethiol molecules with different dipole moments can firmly anchor to the PQD surface through the thiol group to modulate the energy levels of PQDs, and a gradient band structure within the PQD solid is subsequently realized. Consequently, the band-engineered PQDSC delivers an efficiency of up to 16.44%, which is one of the highest efficiencies of CsPbI3 PQDSCs. This work provides a feasible avenue for the band engineering of PQD solids by tuning the surface chemistry of PQDs for high-performing solar cells or other optoelectronic devices.

Electroacupuncture Inhibits Neural Ferroptosis in Rat Model of Traumatic Brain Injury via Activating System Xc-/GSH/GPX4 Axis.

BACKGROUND: Ferroptosis is an iron-dependent regulating programmed cell death discovered recently that has been receiving much attention in traumatic brain injury (TBI). xCT, a major functional subunit of Cystine/glutamic acid reverse transporter (System Xc-), promotes cystine intake and glutathione biosynthesis, thereby protecting against oxidative stress and ferroptosis. OBJECTIVE: The intention of this research was to verify the hypothesis that electroacupuncture (EA) exerted an anti-ferroptosis effect via an increase in the expression of xCT and activation of the System Xc-/GSH/GPX4 axis in cortical neurons of TBI rats. METHODS: After the TBI rat model was prepared, animals received EA treatment at GV20, GV26, ST36 and PC6, for 15 min. The xCT inhibitor Sulfasalazine (SSZ) was administered 2h prior to model being prepared. The degree of neurological impairment was evaluated by means of TUNEL staining and the modified neurological severity score (mNSS). Specific indicators of ferroptosis (Ultrastructure of mitochondria, Iron and ROS) were detected by transmission electron microscopy (TEM), Prussian blue staining (Perls stain) and flow cytometry (FCM), respectively. GSH synthesis and metabolism-related factors in the content of the cerebral cortex were detected by an assay kit. Real-time quantitative PCR (RT-QPCR), Western blot (WB), and immunofluorescence (IF) were used for detecting the expression of System Xc-/GSH/GPX4 axisrelated proteins in injured cerebral cortex tissues. RESULTS: EA successfully relieved nerve damage within 7 days after TBI, significantly inhibited neuronal ferroptosis, upregulated the expression of xCT and System Xc-/GSH/GPX4 axis forward protein and promoted glutathione (GSH) synthesis and metabolism in the injured area of the cerebral cortex. However, aggravation of nerve damage and increased ferroptosis effect were found in TBI rats injected with xCT inhibitors. CONCLUSIONS: EA inhibits neuronal ferroptosis by up-regulated xCT expression and by activating System Xc-/GSH/GPX4 axis after TBI, confirming the relevant theories regarding the EA effect in treating TBI and providing theoretical support for clinical practice.

Recombination and repeat-induced point mutation landscapes reveal trade-offs between the sexual and asexual cycles of Magnaporthe oryzae.

The fungal disease caused by Magnaporthe oryzae is one of the most devastating diseases that endanger many crops worldwide. Evidence shows that sexual reproduction can be advantageous for fungal diseases as hybridization facilitates host-jumping. However, the pervasive clonal lineages of M. oryzae observed in natural fields contradict this expectation. A better understanding of the roles of recombination and the fungi-specific repeat-induced point mutation (RIP) in shaping its evolutionary trajectory is essential to bridge this knowledge gap. Here we systematically investigate the RIP and recombination landscapes in M. oryzae using a whole genome sequencing data from 252 population samples and 92 cross progenies. Our data reveal that the RIP can robustly capture the population history of M. oryzae, and we provide accurate estimations of the recombination and RIP rates across different M. oryzae clades. Significantly, our results highlight a parent-of-origin bias in both recombination and RIP rates, tightly associating with their sexual potential and variations of effector proteins. This bias suggests a critical trade-off between generating novel allelic combinations in the sexual cycle to facilitate host-jumping and stimulating transposon-associated diversification of effectors in the asexual cycle to facilitate host coevolution. These findings provide unique insights into understanding the evolution of blast fungus.

Evolution of a Restriction Factor by Domestication of a Yeast Retrotransposon.

Transposable elements drive genome evolution in all branches of life. Transposable element insertions are often deleterious to their hosts and necessitate evolution of control mechanisms to limit their spread. The long terminal repeat retrotransposon Ty1 prime (Ty1'), a subfamily of the Ty1 family, is present in many Saccharomyces cerevisiae strains, but little is known about what controls its copy number. Here, we provide evidence that a novel gene from an exapted Ty1' sequence, domesticated restriction of Ty1' relic 2 (DRT2), encodes a restriction factor that inhibits Ty1' movement. DRT2 arose through domestication of a Ty1' GAG gene and contains the C-terminal domain of capsid, which in the related Ty1 canonical subfamily functions as a self-encoded restriction factor. Bioinformatic analysis reveals the widespread nature of DRT2, its evolutionary history, and pronounced structural variation at the Ty1' relic 2 locus. Ty1' retromobility analyses demonstrate DRT2 restriction factor functionality, and northern blot and RNA-seq analysis indicate that DRT2 is transcribed in multiple strains. Velocity cosedimentation profiles indicate an association between Drt2 and Ty1' virus-like particles or assembly complexes. Chimeric Ty1' elements containing DRT2 retain retromobility, suggesting an ancestral role of productive Gag C-terminal domain of capsid functionality is present in the sequence. Unlike Ty1 canonical, Ty1' retromobility increases with copy number, suggesting that C-terminal domain of capsid-based restriction is not limited to the Ty1 canonical subfamily self-encoded restriction factor and drove the endogenization of DRT2. The discovery of an exapted Ty1' restriction factor provides insight into the evolution of the Ty1 family, evolutionary hot-spots, and host-transposable element interactions.

Rejuvenating Aged Perovskite Quantum Dots for Efficient Solar Cells.

Perovskite quantum dots (PQDs) have emerged as one of the most promising candidates for next-generation solar cells owing to its remarkable optoelectronic properties and solution processability. However, the optoelectronic properties of PQDs suffer from severe degradation in storage due to the dynamically binding ligands, predominantly affecting photovoltaic applications. Herein, an in situ defect healing treatment (DHT) is reported to effectively rejuvenate aged PQDs. Systematically, experimental studies and theoretical calculations are performed to fundamentally understand the causes leading to the recovered optoelectronic properties of aged PQDs. The results reveal that the I3 - anions produced from tetra-n-octylammonium iodide and iodine could strongly anchor on the surface matrix defects of aged PQDs, substantially diminishing the nonradiative recombination of photogenerated charge carriers. Meanwhile, an DHT could also renovate the morphology of aged PQDs and thus improve the stacking orientation of PQD solids, substantially ameliorating charge carrier transport within PQD solids. Consequently, by using a DHT, the PQD solar cell (PQDSC) yields a high efficiency of up to 15.88%, which is comparable with the PQDSCs fabricated using fresh PQDs. Meanwhile, the stability of PQDSCs fabricated using the rejuvenated PQDs is also largely improved.

CD44 connects autophagy decline and ageing in the vascular endothelium.

The decline of endothelial autophagy is closely related to vascular senescence and disease, although the molecular mechanisms connecting these outcomes in vascular endothelial cells (VECs) remain unclear. Here, we identify a crucial role for CD44, a multifunctional adhesion molecule, in controlling autophagy and ageing in VECs. The CD44 intercellular domain (CD44ICD) negatively regulates autophagy by reducing PIK3R4 and PIK3C3 levels and disrupting STAT3-dependent PtdIns3K complexes. CD44 and its homologue clec-31 are increased in ageing vascular endothelium and Caenorhabditis elegans, respectively, suggesting that an age-dependent increase in CD44 induces autophagy decline and ageing phenotypes. Accordingly, CD44 knockdown ameliorates age-associated phenotypes in VECs. The endothelium-specific CD44ICD knock-in mouse is shorter-lived, with VECs exhibiting obvious premature ageing characteristics associated with decreased basal autophagy. Autophagy activation suppresses the premature ageing of human and mouse VECs overexpressing CD44ICD, function conserved in the CD44 homologue clec-31 in C. elegans. Our work describes a mechanism coordinated by CD44 function bridging autophagy decline and ageing.

XAF1 promotes anti-RNA virus immune responses by regulating chromatin accessibility.

A rapid induction of antiviral genes is critical for eliminating viruses, which requires activated transcription factors and opened chromatins to initiate transcription. However, it remains elusive how the accessibility of specific chromatin is regulated during infection. Here, we found that XAF1 functioned as an epigenetic regulator that liberated repressed chromatin after infection. Upon RNA virus infection, MAVS recruited XAF1 and TBK1. TBK1 phosphorylated XAF1 at serine-252 and promoted its nuclear translocation. XAF1 then interacted with TRIM28 with the guidance of IRF1 to the specific locus of antiviral genes. XAF1 de-SUMOylated TRIM28 through its PHD domain, which led to increased accessibility of the chromatin and robust induction of antiviral genes. XAF1-deficient mice were susceptible to RNA virus due to impaired induction of antiviral genes. Together, XAF1 acts as an epigenetic regulator that promotes the opening of chromatin and activation of antiviral immunity by targeting TRIM28 during infection.

Reproducible evaluation of transposable element detectors with McClintock 2 guides accurate inference of Ty insertion patterns in yeast.

BACKGROUND: Many computational methods have been developed to detect non-reference transposable element (TE) insertions using short-read whole genome sequencing data. The diversity and complexity of such methods often present challenges to new users seeking to reproducibly install, execute, or evaluate multiple TE insertion detectors. RESULTS: We previously developed the McClintock meta-pipeline to facilitate the installation, execution, and evaluation of six first-generation short-read TE detectors. Here, we report a completely re-implemented version of McClintock written in Python using Snakemake and Conda that improves its installation, error handling, speed, stability, and extensibility. McClintock 2 now includes 12 short-read TE detectors, auxiliary pre-processing and analysis modules, interactive HTML reports, and a simulation framework to reproducibly evaluate the accuracy of component TE detectors. When applied to the model microbial eukaryote Saccharomyces cerevisiae, we find substantial variation in the ability of McClintock 2 components to identify the precise locations of non-reference TE insertions, with RelocaTE2 showing the highest recall and precision in simulated data. We find that RelocaTE2, TEMP, TEMP2 and TEBreak provide consistent estimates of [Formula: see text]50 non-reference TE insertions per strain and that Ty2 has the highest number of non-reference TE insertions in a species-wide panel of [Formula: see text]1000 yeast genomes. Finally, we show that best-in-class predictors for yeast applied to resequencing data have sufficient resolution to reveal a dyad pattern of integration in nucleosome-bound regions upstream of yeast tRNA genes for Ty1, Ty2, and Ty4, allowing us to extend knowledge about fine-scale target preferences revealed previously for experimentally-induced Ty1 insertions to spontaneous insertions for other copia-superfamily retrotransposons in yeast. CONCLUSION: McClintock ( https://github.com/bergmanlab/mcclintock/ ) provides a user-friendly pipeline for the identification of TEs in short-read WGS data using multiple TE detectors, which should benefit researchers studying TE insertion variation in a wide range of different organisms. Application of the improved McClintock system to simulated and empirical yeast genome data reveals best-in-class methods and novel biological insights for one of the most widely-studied model eukaryotes and provides a paradigm for evaluating and selecting non-reference TE detectors in other species.

Comparison of the outcome after anterior cervical ossified posterior longitudinal ligament en bloc resection versus posterior total laminectomy and fusion in patients with ossification of the cervical posterior longitudinal ligament: a prospective randomized controlled trial.

The optimal procedure for the treatment of ossification of the posterior longitudinal ligament (OPLL) remains controversial. The aim of this study was to compare the outcome of anterior cervical ossified posterior longitudinal ligament en bloc resection (ACOE) with posterior laminectomy and fusion with bone graft and internal fixation (PTLF) for the surgical management of patients with this condition. Between July 2017 and July 2019, 40 patients with cervical OPLL were equally randomized to undergo surgery with an ACOE or a PTLF. The clinical and radiological results were compared between the two groups. The Japanese Orthopaedic Association (JOA) score and recovery rate in the ACOE group were significantly higher than those in the PTLF group during two years postoperatively, provided that the canal occupying ratio (COR) was > 50%, or the K-line was negative. There was no significant difference in JOA scores and rate of recovery between the two groups in those in whom the COR was < 50%, or the K-line was positive. There was no significant difference in the Cobb angle between C2 and C7, sagittal vertical axis, cervical range of motion (ROM), and complications between the two groups. Compared with PTLF, ACOE is a preferred surgical approach for the surgical management of patients with cervical OPLL in that it offers a better therapeutic outcome when the COR is > 50%, or the K-line is negative, and it also preserves better cervical curvature and sagittal balance. The prognosis of ACOE is similar to that of PTLE when the COR is < 50%, or the K-line is positive.

Reproducible evaluation of transposable element detectors with McClintock 2 guides accurate inference of Ty insertion patterns in yeast.

BACKGROUND: Many computational methods have been developed to detect non-reference transposable element (TE) insertions using short-read whole genome sequencing data. The diversity and complexity of such methods often present challenges to new users seeking to reproducibly install, execute, or evaluate multiple TE insertion detectors. RESULTS: We previously developed the McClintock meta-pipeline to facilitate the installation, execution, and evaluation of six first-generation short-read TE detectors. Here, we report a completely re-implemented version of McClintock written in Python using Snakemake and Conda that improves its installation, error handling, speed, stability, and extensibility. McClintock 2 now includes 12 short-read TE detectors, auxiliary pre-processing and analysis modules, interactive HTML reports, and a simulation framework to reproducibly evaluate the accuracy of component TE detectors. When applied to the model microbial eukaryote Saccharomyces cerevisiae, we find substantial variation in the ability of McClintock 2 components to identify the precise locations of non-reference TE insertions, with RelocaTE2 showing the highest recall and precision in simulated data. We find that RelocaTE2, TEMP, TEMP2 and TEBreak provide a consistent and biologically meaningful view of non-reference TE insertions in a species-wide panel of ∻1000 yeast genomes, as evaluated by coverage-based abundance estimates and expected patterns of tRNA promoter targeting. Finally, we show that best-in-class predictors for yeast have sufficient resolution to reveal a dyad pattern of integration in nucleosome-bound regions upstream of yeast tRNA genes for Ty1, Ty2, and Ty4, allowing us to extend knowledge about fine-scale target preferences first revealed experimentally for Ty1 to natural insertions and related copia-superfamily retrotransposons in yeast. CONCLUSION: McClintock (https://github.com/bergmanlab/mcclintock/) provides a user-friendly pipeline for the identification of TEs in short-read WGS data using multiple TE detectors, which should benefit researchers studying TE insertion variation in a wide range of different organisms. Application of the improved McClintock system to simulated and empirical yeast genome data reveals best-in-class methods and novel biological insights for one of the most widely-studied model eukaryotes and provides a paradigm for evaluating and selecting non-reference TE detectors for other species.

Electrically driven supersymmetric semiconductor laser arrays with single-lobe far-field patterns.

Semiconductor laser arrays based on the third-order supersymmetric (SUSY) transformation are proposed to increase the mode discrimination between fundamental supermode and high-order supermodes. The distance between the edge waveguide of the main array and that of the superpartners is optimized. Then, the electric field distributions of different modes are also calculated, which show that, except for the fundamental supermode, the high-order supermodes penetrate deeper into the superpartner arrays, which accounts for the increased loss of high-order supermodes. The fabricated third-order SUSY laser array can emit light with a single-lobe far-field pattern under an injection current of 70 mA, which is a promising candidate for optical couplings between lasers and optical elements.