Unveiling unconventional CH4-Xe compounds and their thermodynamic properties at extreme conditions.

Inert gases (e.g., He and Xe) can exhibit chemical activity at high pressure, reacting with other substances to form compounds of unexpected chemical stoichiometry. This work combines first-principles calculations and crystal structure predictions to propose four unexpected stable compounds of CH4Xe3, (CH4)2Xe, (CH4)3Xe, and (CH4)3Xe2 at pressure ranges from 2 to 100 GPa. All structures are composed of isolated Xe atoms and CH4 molecules except for (CH4)3Xe2, which comprises a polymerization product, C3H8, and hydrogen molecules. Ab initio molecular dynamics simulations indicate that pressure plays a very important role in the different temperature driving state transitions of CH4-Xe compounds. At lower pressures, the compounds follow the state transition of solid-plastic-fluid phases with increasing temperature, while at higher pressures, the stronger Xe-C interaction induces the emergence of a superionic state for CH4Xe3 and (CH4)3Xe2 as temperature increases. These results not only expand the family of CH4-Xe compounds, they also contribute to models of the structures and evolution of planetary interiors.

Leaf chlorophyll content is the crucial factor for the temporal and spatial variation of global plants leaf maximum carboxylation rate.

Photosynthesis plays an important role in the terrestrial carbon and water cycles which are often studied using terrestrial biosphere models (TBMs). The maximum carboxylation rate at 25 °C (Vcmax25) is a key parameter in the photosynthesis module of TBMs, yet the spatiotemporal distribution of Vcmax25 and the driving mechanism are not fully understood. In this study, Enzyme Kinetics response model, leaf chlorophyll content response model and partial correlation analysis were used to analyze the temporal and spatial changes patterns of atmospheric environment, enzyme dynamic and soil nutrition on Vcmax25 and the driving mechanism, and has made a few useful conclusions: (1) Vcmax25 varies significantly with latitude and between- and within-plant function types (PFTs), which mainly dependent on leaf chlorophyll content (LCC). Under the influence of temperature, the contribution of LCC to the seasonal variation of Vcmax25 is very different among the eight main biomes, with an average contribution of 21 %. (2) The relationship between meteorological variables and Vcmax25 was significant, due to the fact that meteorological variables drive the Rubisco enzyme content that have a significant relationship with Vcmax25, rather than directly acting on Vcmax25. (3) Soil nutrient elements had significant influence on the spatiotemporal variation of Vcmax25 and LCC. The results showed that soil total carbon, soil nitrogen and organic carbon not only affect the temporal and spatial pattern of Vcmax25, but also are the key factors of LCC temporal-spatial variation. These findings provide useful information for better parameterization of Vcmax25 in TBMs.

Layer Control of Magneto-Optical Effects and Their Quantization in Spin-Valley Splitting Antiferromagnets.

Magneto-optical effects (MOE), interfacing the fundamental interplay between magnetism and light, have served as a powerful probe for magnetic order, band topology, and valley index. Here, based on multiferroic and topological bilayer antiferromagnets (AFMs), we propose a layer control of MOE (L-MOE), which is created and annihilated by layer-stacking or an electric field effect. The key character of L-MOE is the sign-reversible response controlled by ferroelectric polarization, the Néel vector, or the electric field direction. Moreover, the sign-reversible L-MOE can be quantized in topologically insulating AFMs. We reveal that the switchable L-MOE originates from the combined contributions of spin-conserving and spin-flip interband transitions in spin-valley splitting AFMs, a phenomenon not observed in conventional AFMs. Our findings bridge the ancient MOE to the emergent realms of layertronics, valleytronics, and multiferroics and may hold immense potential in these fields.

Design of Zeolitic Imidazolate Framework-8-Functionalized Capacitive Micromachined Ultrasound Transducer Gravimetric Sensors for Gas and Hydrocarbon Vapor Detection.

A capacitive micromachined ultrasound transducer (CMUT) was engineered and functionalized with zeolitic imidazolate framework-8 (ZIF-8) dispersed in a photoresist AZ1512HS (AZ) matrix to function as a gravimetric gas sensor. The sensor response was recorded in the presence of nitrogen, argon, carbon dioxide, and methane gases as well as water, acetylene, a propane/butane mixture, n-hexane, gasoline, and diesel vapors. The photoresist matrix alone was found to have a negligible response to all the gases and vapors, except for water vapor. No visible difference in sensor response was detected when switching from nitrogen to methane gas. However, a strong shift in the sensor resonance frequency was observed when exposed to higher hydrocarbons, ranging from 1 kHz for acetylene to 7.5 kHz for gasoline. Even longer-chain hydrocarbons, specifically kerosene and more so diesel, had a significantly reduced sensor frequency shift compared with gasoline. Sensors functionalized with a thin film of AZ+ZIF-8 demonstrated higher sensitivity in their response to a hydrocarbon molecular mass than without functionalization.

Prediction of a reservoir of N-rich high-energy density material at the Earth's mantle.

Water and nitrogen are abundant in the Earth's interior and atmosphere, and their mixture under high pressure is a fundamental and valuable scientific issue for physics and chemical science. Based on structural prediction and first-principles simulations, we propose that the two nitrogen-rich stoichiometries, H2ON6 and H2ON10, become energetically stable above ∼70 GPa. Further ab initio molecular dynamics calculations indicate that H2ON6 and H2ON10 undergo phase transitions from solid to superionic and finally to fluid phase with increasing temperature. The superionic regions in their phase diagram correspond to the extreme conditions of Earth's mantle, implying that the Earth's interior might be a possible reservoir of the N-rich hydrates. In addition, H2ON6 remains dynamically stable under ambient conditions with an estimated energy density of 6.53 kJ g-1, indicating that it might be a high-energy density material. These results not only provide essential information for the understanding of the Earth's interior, but also provide guidance for the design of high-energy density materials.

Clinical Observation of Uninterrupted Thrombolytic Therapy via Indwelling Catheter for Lower Limb Deep Vein Thrombosis.

Purpose: Observe uninterrupted thrombolytic therapy via indwelling catheter for lower limb deep vein thrombosis. Methods: We retrospectively studied data from 32 patients with lower extremity deep vein thrombosis who received comprehensive treatment, consisting of general treatment, inferior vena cava filter implantation, interventional thrombolysis, angioplasty, stenting, and post-operative monitoring. Results: The efficacy and safety of the comprehensive treatment were observed for a follow-up period of 6-12 months. The treatment was 100% effective; patient results indicated no serious bleeding, acute pulmonary embolism, or death after surgery. Conclusion: The combination of intravenous and healthy side femoral vein puncture and directed thrombolysis to treat acute lower limb deep vein thrombosis is safe, effective, and minimally invasive while still achieving a good therapeutic effect.

Superconducting H7 chain in gallium hydrides at high pressure.

Pressure-stabilized hydrides have potential as an outstanding reservoir for high-temperature (Tc) superconductors. We undertook a systematic study of crystal structures and superconducting properties of gallium hydrides using an advanced structure-search method together with first-principles calculations. We identified an unconventional stoichiometric GaH7 gallium hydride that is thermodynamically stable at pressures above 247 GPa. Interestingly, the H atoms are clustered to form a unique H7 chain intercalating the Ga framework. Further calculations show a high estimated Tc above 100 K at 200-300 GPa for GaH7, closely related to the strong coupling between electrons of Ga and H atoms, and phonon vibrations of H7 chains. Our work provides an example of exploration for diverse superconducting hydrogen motifs under high pressure, and may stimulate further experimental syntheses.

N-terminal Domain of Amyloid-ß Impacts Fibrillation and Neurotoxicity.

Alzheimer's disease is characterized by the presence of distinct amyloid-ß peptide (Aß) assemblies with diverse sizes, shapes, and toxicity. However, the primary determinants of Aß aggregation and neurotoxicity remain unknown. Here, the N-terminal amino acid residues of Aß42 that distinguished between humans and rats were substituted. The effects of these modifications on the ability of Aß to aggregate and its neurotoxicity were investigated using biochemical, biophysical, and cellular techniques. The Aß-derived diffusible ligand, protofibrils, and fibrils formed by the N-terminal mutational peptides, including Aß42(R5G), Aß42(Y10F), and rat Aß42, were indistinguishable by conventional techniques such as size-exclusion chromatography, negative-staining transmission electron microscopy and silver staining, whereas the amyloid fibrillation detected by thioflavin T assay was greatly inhibited in vitro. Using circular dichroism spectroscopy, we discovered that both Aß42 and Aß42(Y10F) generated protofibrils and fibrils with a high proportion of parallel ß-sheet structures. Furthermore, protofibrils formed by other mutant Aß peptides and N-terminally shortened peptides were incapable of inducing neuronal death, with the exception of Aß42 and Aß42(Y10F). Our findings indicate that the N-terminus of Aß is important for its fibrillation and neurotoxicity.

Micropulse laser trabeculoplasty on Chinese patients with glaucoma or ocular hypertension: average 35 months follow-up results.

BACKGROUND: Glaucoma is a group of eye diseases that can damage the optic nerve and cause vision loss. A novel technology micropulse laser trabeculoplasty (MLT) can use duty-circle subvisible laser pulses to treat glaucoma. The aim of this study is to evaluate the efficacy of 360° MLT to alleviate intraocular pressure (IOP) in patients with glaucoma. METHODS: This was a single-center prospective study on patients treated with 360° MLT using a Diode True-Yellow 577-nm Laser with MicroPulse technology. All the patients were recruited from the Department of Ophthalmology. Follow-up visits were carried out at 1 day, 1 week, 1 month, 3 months, 6 months, 18 months, and 36 months after the procedure. Best-corrected visual acuity (BCVA), Intraocular pressure (IOP), and vertical cup-to-disc ratio (C/D ratio) were measured during the follow-up. Repeated-measures analysis of variance (ANOVA) and Kaplan-Meier analysis were performed to evaluate the outcomes. RESULTS: A total of 39 eyes from 25 patients were included in this study (10 men/15 women). The average age of patients was 41.47 ± 14.39 years old, and the baseline IOP was 21.13 ± 7.75 mmHg. MLT significantly reduced the IOP at 1 day (range 15.61-19.01, P = 0.0218), 3 months (range 16.47-19.22, P = 0.0390), and 6 months (range 15.38-18.56, P = 0.0332) compared with the baseline. However, by the end of the study, only 21.88% of patients demonstrated a ≥ 20% IOP reduction, while seven eyes needed further laser or surgical treatment. The IOP of glaucoma patients was significantly lower than the ocular hypertension patients at 1 month (P = 0.0124), 3 months (P = 0.0004), 18 months (P = 0.0061) and 36 months (P = 0.0119). CONCLUSIONS: Micropulse laser trabeculoplasty reduce IOP in patients with glaucoma or ocular hypertension for a short period, but its lowering efficiency is limited up to 6 months of the follow-up period.

C-reactive protein inhibits C3a/C3aR-dependent podocyte autophagy in favor of diabetic kidney disease.

Numerous studies have reported the pathogenic roles of C-reactive protein (CRP) and complement activation in diabetic kidney disease (DKD) individually. However, considering the potent regulatory effect of CRP on complement activation, it remains unclear whether CRP participates in DKD pathogenesis by regulating complement activation. Moreover, this work focuses on complement activation in rats, which aims at settling the dispute that whether rat CRP can activate the complement system. To address this question, the complement effectors C3a, C5a, and C5b-9 were examined in human patients with diabetic nephropathy (DN) and wt, Crp-/- , and huCRPtg rats with STZ-diabetic DKD. The Crp-/- rats showed more C3a accumulation in blood and glomeruli than wt and huCRPtg rats. The balance between autophagy and apoptosis was evaluated in DKD rats, and Crp-/- rats showed increased podocyte autophagy compared with wt and huCRPtg rats. Meanwhile, stable CRP-overexpression and CRP-knockout cell lines were established and used to demonstrate that CRP suppresses C3a-induced podocyte autophagy under high-glucose conditions. We further verified that the inhibition of C3a-induced podocyte autophagy by CRP was dependent on C3aR expression and that this effect could be reversed with a C3aR antagonist and agonist. Therefore, our findings provide evidence that CRP suppresses podocyte autophagy to accelerate the development of DKD by inhibiting C3a/C3aR axis signaling, which may help in the development of a new therapeutic strategy for the management of podocyte autophagy and DKD. In addition, rat CRP has been shown to be identical to human CRP in the activation of autologous complement and interspecific complement.

ML365 inhibits lipopolysaccharide-induced inflammatory responses via the NF-κB signaling pathway.

ML365 is a selective inhibitor of the twik-related acid-sensitive potassium channel 1/two-pore domain channel subfamily k member 3 two-pore domain potassium channel. There are no functional studies of the relationship between ML365 and inhibition of inflammation. In this study, we evaluated the anti-inflammatory effect of ML365 on lipopolysaccharide (LPS)-induced inflammation and elucidated the possible mechanism. ML365 showed no cytotoxicity and did not induce apoptosis on RAW264.7 cells and inhibited nitric oxide production. ML365 suppressed the release of tumor necrosis factor-alpha, interleukin (IL)-6 and IL-1ß measured using enzyme-linked immunosorbent assay and quantitative polymerase chain reaction assays. LPS-induced activation and co-localization of NF-κB was inhibited by ML365 pre-treatment. ML365 inhibited the protein expression of Erk, p38 and Jnk. In vivo, ML365 appeared to prevent pathological damages in the LPS-induced endotoxin shock model. These findings suggest that ML365 inhibits LPS-induced inflammatory responses by regulating the NF-κB signaling pathway.

The Role of Problematic Smartphone Uses and Psychological Distress in the Relationship Between Sleep Quality and Disordered Eating Behaviors Among Chinese College Students.

Background: Sleep problems and eating disorders (EDs) are both serious public health concerns often seen in young adults. Yet, the underlying mechanisms for such associations are largely unknown. This study aims to examine potential serial multiple mediation effects of problematic smartphone use (PSU) and psychological distress (i.e., depressive and anxiety symptoms) in the relationship between sleep quality and disordered eating behaviors/attitudes (DEBs). Methods: A total of 4,325 students from two Tibet universities in China (2,657 females and 1,668 males) completed an online survey that included the following measurements: Eating Attitude Test-26 for disordered eating behaviors/attitudes, the Chinese Version of Pittsburgh Sleep Quality Index (CPSQI), Smartphone Addiction Scale-Short Version (SAS-SV) for problematic smartphone use, Patient Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorder-7 (GAD-7) for psychological distress. Results: While the direct path linking sleep quality and DEBs was not found to be significant (Standardized ß = 0.006, 95% CI = -0.0667~0.0970), both PSU (Standardized ß = 0.016, 95% CI = 0.0256~0.0591) and anxiety symptoms (Standardized ß = 0.014, 95% CI = 0.0203~0.0526) may mediate a link between sleep quality and DEBs; serial multiple mediation analysis revealed that a serial indirect pathway of "sleep quality -> PSU -> anxiety symptoms -> DEBs" existed(Standardized ß = 0.001, 95% CI = 0.0002~0.0012). Similarly, while the direct path linking sleep quality and DEBs was not found to be significant (Standardized ß = 0.006, 95% CI = -0.0667~0.0970), both PSU (Standardized ß = 0.020, 95% CI = 0.0337~0.0692) and depressive symptoms (Standardized ß = 0.015, 95% CI = 0.0139~0.0652) may mediate a link between sleep quality and DEBs; serial multiple mediation analysis revealed that a serial indirect pathway of "sleep quality -> PSU -> depressive symptoms -> DEBs" existed (Standardized ß = 0.001, 95% CI = 0.0006~0.0038). Conclusions: Psychological and behavioral factors may comprehensively work together, leading to flow-on effects from sleep problems to disordered eating behaviors among university students. Appropriate interventions that target problematic smartphone use could thus potentially reduce anxiety and depression levels, which in turn will provide a buffer against the negative impact of poor sleep quality on eating disorder symptoms.

Halogen molecular modifications at high pressure: the case of iodine.

Metallization and dissociation are key transformations in diatomic molecules at high densities particularly significant for modeling giant planets. Using X-ray absorption spectroscopy and atomistic modeling, we demonstrate that in halogens, the formation of a connected molecular structure takes place at pressures well below metallization. Here we show that the iodine diatomic molecule first elongates by ∼0.007 Å up to a critical pressure of Pc ∼ 7 GPa, developing bonds between molecules. Then its length continuously decreases with pressure up to 15-20 GPa. Universal trends in halogens are shown and allow us to predict for chlorine a pressure of 42 ± 8 GPa for molecular bond-length reversal. Our findings contribute to tackling the molecule invariability paradigm in diatomic molecular phases at high pressures and may be generalized to other abundant diatomic molecules in the universe, including hydrogen.

A PITX2 splice-site mutation in a family with Axenfeld-Rieger syndrome leads to decreased expression of nuclear PITX2 protein.

PURPOSE: Axenfeld-Rieger syndrome (ARS) is an autosomal dominant disorder characterized by ocular anterior segment abnormalities. In the current study, we describe clinical and genetic findings in a Chinese ARS pedigree. METHODS: An ARS pedigree was recruited and patients were given comprehensive ophthalmic examinations and general physical examinations. DNA from the proband II:2 was used for exome sequencing. Sanger sequencing was utilized to identify and validate PITX2 variations. qPCR and western blotting were performed to detect PITX2 expression in immortalized peripheral blood lymphocytes. RESULTS: All affected family members showed typical ocular abnormalities, including iris atrophy, corectopia, shallow anterior chamber, complete or partial angle closure, and advanced glaucoma. They also exhibited systemic anomalies, such as microdontia, hypodontia, and redundant periumbilical skin. A heterozygous splice-site variation c.390 + 1G > A in PITX2, which might lead to a truncated PITX2 protein (p.Val131IlefsX127), was found in the proband. Sanger sequencing validated that the variation completely co-segregated with the ARS phenotype within this family and was absent in 100 unrelated controls. Western blotting revealed that the nuclear PITX2 protein was significantly decreased in patients compared with controls. Nonetheless, there was no significant difference in the total PITX2 protein level, consistent with qPCR results showing no alteration in PITX2 mRNA levels in the patient group. CONCLUSIONS: PITX2 c.390 + 1G > A (p.Val131IlefsX127) was a novel genetic etiology of the ARS pedigree. The mutation leads to decreased nuclear PITX2, indicating lower transcriptional activity.

High-Pressure Phases and Properties of the Mg3Sb2 Compound.

Pressure always plays an important role in influencing the structure configuration and electronic properties of materials. Here, combining density function theory and structure prediction algorithm, we systematically studied the Mg3Sb2 system from its phase transition to thermodynamic and electronic properties under high pressure. We find that two novel phases, namely Cm and C2/m, are stable under high pressure. Calculation results of phonon dispersions showed that both novel phases have no imaginary frequency, which indicates that the novel phases are thermodynamically stable. Due to the larger ionic radius of Sb compared to N, P, and As elements, the Mg3Sb2 compound shows a different electronic property at high pressure. The electronic calculations show that the novel phases of Cm and C2/m of Mg3Sb2 possess metallic behavior under high pressure. These results provide new insights for understanding the Mg3Sb2 compound.

Hidden porous boron nitride as a high-efficiency membrane for hydrogen purification.

Nanoporous atom-thick two-dimensional materials with uniform pore size distribution and excellent mechanical strength have been considered as the ideal membranes for hydrogen purification. Here, our first-principles structure search has unravelled four porous boron nitride monolayers (m-BN, t-BN, h'-BN and h''-BN) that are metastable relative to h-BN. Especially, h'-BN consisting of B6N6 rings exhibits outstanding selectivity and permeability for hydrogen purification, higher than those of common membranes. Importantly, h'-BN possesses the mechanical strength to sustain a stress of 48 GPa, which is two orders of magnitude higher than that (0.38 GPa) of a recently reported graphene-nanomesh/single-walled carbon nanotube network hybrid membrane. The excellent selectivity, permeability and mechanical strength make h'-BN an ideal candidate for hydrogen purification.

Endocytosis Is a Key Mode of Interaction between Extracellular ß-Amyloid and the Cell Membrane.

Interactions between amyloid-ß peptide (Aß) and the cell membrane include interaction with membrane lipids and binding to membrane receptors, both of which are considered to be the toxicity mechanisms of Aß. However, it is unclear whether both mechanisms lead to cytotoxicity. Thus, we aimed to analyze these two mechanisms of Aß42 interaction with cell membranes under different Aß aggregation states. To this end, model membrane experiments were conducted. Quantitative analysis of Aß42 monomers or oligomers bound to the membrane of neuro-2a cells was also performed, and laser confocal microscopy was employed to assess endocytosis of FITC-Aß42 monomers or oligomers by neuro-2a cells. We found that the binding capacity of Aß42 to membrane lipids was weak and that the amount of Aß42 bound to membrane lipids was low. Moreover, clathrin-mediated endocytosis of Aß42 oligomers by neuro-2a cells was observed. Endocytosis serves as a key mode of interaction between extracellular Aß42 and neurons. These findings provide insights into the mechanisms underlying Aß oligomer metabolism.