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The formation of planets in our solar system encompassed various stages of accretion of planetesimals that formed in the protoplanetary disk within the first few million years at different distances to the sun. Their chemical diversity is reflected by compositionally variable meteorite groups from different parent bodies. There is general consensus that their formation location is roughly constrained by a dichotomy of nucleosynthetic isotope anomalies, relating carbonaceous (C) meteorite parent bodies to the outer protoplanetary disk and the non-carbonaceous (NC) parent bodies to an origin closer to the sun. It is a common idea, that in these inner parts of the protoplanetary disks, planetesimal accretion processes were faster. Testing such scenarios requires constraining formation ages of meteorite parent bodies. Although isotopic age dating can yield precise formation ages of individual mineral constituents of meteorites, such ages frequently represent mineral cooling ages that can postdate planetesimal formation by millions or tens of millions of years, depending on the cooling history of individual planetesimals at different depths. Nevertheless, such cooling ages provide a detailed thermal history which can be fitted by thermal evolution models that constrain the formation age of individual parent bodies. Here we apply state-of-the-art thermal evolution models to constrain planetesimal formation times particular in the outer solar system formation region of C meteorites. We infer a temporally distributed accretion of various parent bodies from < 0.6 Ma to ≈ 4 Ma after solar system formation, with 3.7 Ma and 2.5 - 2.75 Ma for the parent bodies of CR1-3 chondrites and the Flensburg carbonaceous chondrite, and < 0.6 and < 0.7 Ma for the parent bodies of differentiated achondrites NWA 6704 and NWA 011, respectively. This implies that accretion processes in the C reservoir started as early as in the NC reservoir and were operating throughout typical protoplanetary disk lifetimes, thereby producing differentiated parent bodies with carbonaceous compositions in addition to undifferentiated C chondrite parent bodies. The accretion times correlate inversely with the degree of the meteorites' alteration, metamorphism, or differentiation. The accretion times for the CM, CI, Ryugu, and Tafassite parent bodies of 3.8 Ma, 3.8 Ma, 1 - 3 Ma, and 1.1 Ma, respectively, fit well into this correlation in agreement with the thermal and alteration conditions suggested by these meteorites. Our results indicate that individual planetesimals formed rapidly (i.e., within < 1 Ma), however, distinct planetesimals formed recurrently throughout the total lifetime of the protoplanetary disk. Rapid individual formation is consistent with streaming instabilities assisted by gravitational collapse. However, obviously not the total dust inventory was consumed at early disk evolution stages, so there must have been some delay mechanisms, e.g. collisional destruction of precursor aggregates due to high impact velocities induced by radial drift phenomena. This counterbalance enabled late ( > 2 - 3 Ma) accretion of C planetesimals beyond the snow line which escaped severe planetesimal heating and volatile loss, hence, preserving their volatiles, especially water. Only this delayed formation of water-rich planetesimals allowed Earth to accrete sufficient water to become a habitable planet, preventing it from being a bone dry planet. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD), a chronic neurodegenerative disorder, is the leading cause of dementia. Over-activated microglia is related to amyloid-beta (Aβ) and phosphorylated tau (phospho-tau) accumulation in the AD brain. Taurine is an amino acid with multiple physiological functions including anti-inflammatory effects, and has been reported to be neuroprotective in AD. However, the role of taurine in microglia-mediated AD remains unclear. Here, we examined the effects of taurine on the brains of senescence-accelerated mouse prone 8 (SAMP8) mice by comparing those administered 1% taurine water with those administered distilled water (DW). We observed increased levels of taurine and taurine transporter (TAUT) in the brains of the taurine-treated mice compared with those of control mice. Immunohistochemical and Western blot analyses revealed that taurine significantly reduced the number of activated microglia, levels of phospho-tau and Aβ deposit in the hippocampus and cortex. Triggering receptors expressed on myeloid cells-2 (TREM2) are known to protect against AD pathogenesis. Taurine upregulated TREM2 expression in the hippocampus and cortex. In conclusion, the present study suggests that taurine treatment may upregulate TREM2 to protect against microglia over-activation by decreasing the accumulation of phospho-tau and Aβ; providing an insight into a novel preventive strategy in AD. [ABSTRACT FROM AUTHOR]

The co-segregation of Cu and Mg solutes at grain boundaries (GBs) in Al alloys is widely observed in experiments, but this segregation pattern is much less understood. Herein, the Cu, Mg co-segregation behaviors and their effects on Al Σ5 (210) GB properties were systematically studied via first-principles calculations. The segregation order of Cu and Mg atoms was firstly determined wherein the segregation tendency of Cu is comparatively stronger than Mg. Calculations demonstrate that Cu and Mg atoms exhibit attractive interaction, which would promote synergistic co-segregation of both dopants at the GB. It is revealed that Cu, Mg co-segregation not only improves GB thermodynamic stability, but also enhances the GB fracture strength. Detailed analysis of charge density, bonding characteristics, etc., suggests that the newly formed Al–Cu bonds upon Cu segregation are the primary contribution to the increased GB cohesion. The further Mg doping at the Al GB with Cu segregation results in charge depletion and meanwhile decreases Al–Cu bonding length, the net results of which increase GB cohesion, suggesting a synergistically enhanced GB strength with Mg and Cu co-segregation. This work is supposed to provide fundamental insights into the effect of Cu, Mg co-segregation on the strength of Al GBs. [ABSTRACT FROM AUTHOR]

Silica hollow tube (SHT) nanofillers were fine distributed in poly(ether ketone ketone) (PEKK) to serve decently as sixth generation (6G) substrate films. Distinctly lower dielectric and thermal expansion characteristics were detected for all PEKKaxSHTy film sequence filled with proper amounts of SHT nanofillers. The dielectric characteristics detected for all PEKKaxSHTy film sequence diminished to a minimum, as SHT loads came near an optimal value of 8wt%. The LCTE evaluated for each PEKKaxSHTy film sequence reduced distinctly with increasing SHT loads. Suitable dielectric constant (εr) (2.26 at 1 MHz), and/or dielectric loss (tan δ) (0.0027 at 1 MHz) and/or Linear coefficient of thermal expansion (LCTE) (30.5 × 10−6/ °C) for 6G rapid-speed communication were detected for PEKKP700092SHT8 substrate film having 8wt% load of SHT nanofillers. Meanwhile, the beginning degradation temperatures estimated for all PEKKaxSHTy film sequence increased distinctly with increasing SHT loads. All free-volume-cavity characteristics estimated for all PEKKaxSHTy film sequence approached a highest value, as SHT loads came near an optimal value of 8wt%. Distinctly lower εr and tan δ were detected for PEKKa and PEKKaxSHTy having higher free-volume-cavity characteristics. Possible interpretations for the distinctly diminished dielectric and/or heat-resistant characteristics acquired for PEKKaxSHTy films are presented. [ABSTRACT FROM AUTHOR]

Identifying high-risk regions and turning points of influenza with a precise spatiotemporal scale may provide effective prevention strategies. In this study, epidemiological characteristics and spatiotemporal clustering analysis at the township level were performed. A descriptive study and a Joinpoint regression analysis were used to explore the epidemiological characteristics and the time trend of influenza. Spatiotemporal autocorrelation and clustering analyses were carried out to explore the spatiotemporal distribution characteristics and aggregation. Furthermore, the hotspot regions were analyzed by spatiotemporal scan analysis. A total of 4025 influenza cases were reported in Yinchuan showing an overall increasing trend. The tendency of influenza in Yinchuan consisted of three stages: increased from 2012 to the first peak in 2019 (32.62/100,000) with a slight decrease in 2016; during 2019 and 2020, the trend was downwards; then it increased sharply again and reached another peak in 2022. The Joinpoint regression analysis found that there were three turning points from January 2012 to December 2022, namely January 2020, April 2020, and February 2022. The children under ten displayed an upward trend and were statistically significant. The trend surface analysis indicated that there was a shifting trend from northern to central and southern. A significant positive spatial auto-correlation was observed at the township level and four high-incidence clusters of influenza were detected. These results suggested that children under 10 years old deserve more attention and the spatiotemporal distribution of high-risk regions of influenza in Yinchuan varies every year at the township level. Thus, more monitoring and resource allocation should be prone to the four high-incidence clusters, which may benefit the public health authorities to carry out the vaccination and health promotion timely. [ABSTRACT FROM AUTHOR]

The coordination chemistry of the organotin(IV) compounds is dominated by nitrogen and oxygen donor ligands. Some of these complexes have found prominent applications in the fields of biomedicine such as anticancer and antibacterial agents. These complexes represent important building blocks in polymer and supramolecular assembly. This review aims to summarize the recent literature on the chemistry of organotin complexes with imine and polypyridyl ligands such as bipyridine, phenanthroline and terpyridine ligands as well as oxygen donor ligands and O, N donor ligands. Given that many organotin(IV) chlorides are inexpensive, widely available, and can be easily converted to the other corresponding halides and pseudo-halides, numerous innovative ideas could be generated through application of these compounds. Polymer-containing tin moieties were also highlighted and their biological activities in combatting diseases such as cancer and inflammatory and infectious diseases were described. [ABSTRACT FROM AUTHOR]

Background: Understanding sex disparities in stroke can identify gaps in clinical care. The objective of this study was to investigate whether sex differences could influence clinical outcomes of patients with acute vertebrobasilar artery occlusion (VBAO) who underwent endovascular therapy (EVT). Methods: Patients were selected from the ANGEL-ACT Registry. The primary outcome was favorable functional outcome (90-day modified Rankin Scale [mRS] 0–3). Secondary outcomes included 90-day mRS distribution, excellent outcome (mRS 0–1), functional independence (mRS 0–2), early neurological improvement, recanalization, intracranial hemorrhage, and mortality within 90 days. The above outcomes were compared by two adjustment models, including (1) multivariable logistics analysis adjusting for all baseline and procedural variables with a P < 0.05; (2) adjusting for the propensity score. Results: There were 347 acute VBAO patients treated with EVT included, of whom 72 (20.7%) were women and 275 (79.3%) were men. Women were older (72[63–76] vs. 62[53–69], P < 0.001) and had a higher rate of atrial fibrillation (31.9% vs. 8.7%, P < 0.001), lower rates of underlying intracranial atherosclerotic disease (30.6% vs. 51.3%, P = 0.007), and tandem occlusion (8.3% vs. 21.8%, P = 0.009) than men. The rate of favorable outcome (mRS 0–3) was similar between women and men (41.7% vs. 51.3%, adjusted odds ratio 1.56, 95%CI: 0.83–2.95, P = 0.171). There were no sex differences in other clinical outcomes (all P > 0.05). Conclusions: In the ANGEL-ACT registry, the percentage of men with acute VBAO undergoing EVT was approximately fourfold higher than that of women with acute VBAO undergoing EVT. Sex differences did not modify the outcomes of acute VBAO after EVT. [ABSTRACT FROM AUTHOR]

Background: The clinical efficacy and safety of intravenous immunoglobulin (IVIg) treatment for COVID-19 remain controversial. This study aimed to map the current status and gaps of available evidence, and conduct a meta-analysis to further investigate the benefit of IVIg in COVID-19 patients. Methods: Electronic databases were searched for systematic reviews/meta-analyses (SR/MAs), primary studies with control groups, reporting on the use of IVIg in patients with COVID-19. A random-effects meta-analysis with subgroup analyses regarding study design and patient disease severity was performed. Our outcomes of interest determined by the evidence mapping, were mortality, length of hospitalization (days), length of intensive care unit (ICU) stay (days), number of patients requiring mechanical ventilation, and adverse events. Results: We included 34 studies (12 SR/MAs, 8 prospective and 14 retrospective studies). A total of 5571 hospitalized patients were involved in 22 primary studies. Random-effects meta-analyses of very low to moderate evidence showed that there was little or no difference between IVIg and standard care or placebo in reducing mortality (relative risk [RR] 0.91; 95% CI 0.78–1.06; risk difference [RD] 3.3% fewer), length of hospital (mean difference [MD] 0.37; 95% CI − 2.56, 3.31) and ICU (MD 0.36; 95% CI − 0.81, 1.53) stays, mechanical ventilation use (RR 0.92; 95% CI 0.68–1.24; RD 2.8% fewer), and adverse events (RR 0.98; 95% CI 0.84–1.14; RD 0.5% fewer) of patients with COVID-19. Sensitivity analysis using a fixed-effects model indicated that IVIg may reduce mortality (RR 0.76; 95% CI 0.60–0.97), and increase length of hospital stay (MD 0.68; 95% CI 0.09–1.28). Conclusion: Very low to moderate certainty of evidence indicated IVIg may not improve the clinical outcomes of hospitalized patients with COVID-19. Given the discrepancy between the random- and fixed-effects model results, further large-scale and well-designed RCTs are warranted. [ABSTRACT FROM AUTHOR]

In our recent paper, we reported the development and application of the aerosol injection technique to accelerate the consolidation in soft soils. Aerosol injection technique is a process that involves injecting air under high pressure into soft soil to create a network of fractures, which gives rise to enhanced permeability. In this paper, we present an experimental study on the permeability of soft soil specimens with pre-made fractures in a triaxial device. Some emphasis is given to the variation of permeability with time. Some major influence factors are considered, e.g. the fracture roughness, confining pressure, pre-consolidation pressure, soil structure and mineral composition. The decrease in permeability with time is mainly due to the self-healing mechanism in soft soils, which is dictated by the soil deformation and migration of fines driven by the confining pressure and hydraulic gradient. [ABSTRACT FROM AUTHOR]

The spectrum of surface plasmon polaritons in double-layer graphene with and without an external magnetic field by utilizing Maxwell’s equations in a hydrodynamic model was studied and field configurations were analyzed. There is neither a transverse magnetic (TM) mode nor a transverse electric (TE) mode but a full-field mode under the external field. Regardless of the presence or absence of an external field, the excited transverse magnetic field is symmetrical in the acoustic branch, whereas it is antisymmetrical in the optical branch. Meanwhile, the excited transverse electric field has opposite symmetry properties against to that of the transverse magnetic field. The results indicate that the rise of the spectrum is dominated by an external magnetic field in the infrared region and a non-local effect in the ultraviolet region. The influence of the layer distance on the spectrum was also studied. [ABSTRACT FROM AUTHOR]

High-performance organometallic materials based on phthalocyanine (Pc) thin films with nickel, copper, manganese and silicon were deposited onto glass substrates using spin-coating technique at room temperature. The physical properties of the films were characterized to evaluate the influence of the dopant metal on their performance. Various analytical techniques, including X-ray diffraction analysis (XRD), Raman spectroscopy (RS), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and ultraviolet–visible transmittance spectroscopy, were employed to investigate the characteristics of the prepared films. For every sample, the produced films showed amorphous structure and crystallization. Analyses using XPS were done. It was discovered that there are three peaks in the composite C1s X-Pc signal, which is relevant to the interpretation of the main C1s signal. Analysis of SEM images revealed a uniform, dense, and homogeneous structure in the films, with minimal pores and microcracks. Optical analysis showcased remarkable visible-range optical absorption and an optical direct band gap ranging from  3.15 to  3.72 eV, along with exceptional transmission properties. The comprehensive exploration of the physical and optical characteristics of these phthalocyanine films positions the material as a promising candidate for advancements in solar cell technology, paving the way for potential breakthroughs in innovative and efficient solar energy applications. [ABSTRACT FROM AUTHOR]

Anthracycline chemotherapy is associated with the left ventricular (LV) dysfunction, but the conventional echocardiographic parameter is insensitive in detecting subclinical cardiac dysfunction, and the role of echocardiography in children cancer survivors (CCSs) has not been well established. Here, the myocardial work (MW) was employed to evaluate the early effect of the anthracyclines on LV function in children lymphoma survivors, as well as to explore the clinical application value of this modality. 51 children lymphoma survivors treated with anthracyclines were included. During the treatments, the echocardiography was performed at baseline (T0 phase), the 3rd (T1 phase) and 6th (T2 phase) chemotherapeutic cycle, respectively. After that, the conventional echocardiographic parameters, LV global longitudinal strain (GLS), and global myocardial work (GMW) parameters were obtained. Finally, these echocardiographic parameters were compared to distinguish the differences among three groups, and correlation analysis was used to identify relationship between GMW parameters and LV GLS. Compared with the baseline, we found that there are no significant differences for LVEF and other conventional echocardiographic parameters after chemotherapy, but the value of LV lateral E/E’ increased at T1 and T2 group. The GLS, global work index, global constructed work, and global work efficiency were decreased, while the global wasted work was increased after chemotherapy (all P < 0.05). The correlation analysis showed that the GLS has significant correlation with GMW parameters (all P < 0.001). The MW, as a new noninvasive echocardiography modality, could be used to quantitatively evaluate the LV MW in children lymphoma survivors treated with anthracyclines, which providing a sensitive method to early detect the children’s LV dysfunction after the chemotherapy. [ABSTRACT FROM AUTHOR]

Mechanoluminescence (ML), a process that converts external mechanical energy into light energy, offers a solution to challenges in the area of energy saving by not requiring a load power supply. From the 17th century, when people started to explore this field, from the fracture luminescence of materials to the emergence of elastic-ML (EML) materials, there has been a great deal of research into the mechanisms and applications of ML. Piezoelectric properties are extremely important for ML materials, and most ML materials today have piezoelectric properties. Among them, quaternary oxysulfides M(Ca, Sr, Ba)ZnxSxO (x = 1, 2) are wide bandgap piezoelectric semiconductors developed in the 21st century. The doping of transition elements, trivalent lanthanides, and other metal-emitting ions has been realized in the last 20 years of development, and all of them show excellent ML properties. Quaternary oxysulfides have become significant inorganic mechanoluminescent materials. This article provides a detailed description of the development process, mechanism, performance optimization, and applications of quaternary oxysulfides, and highlights future trends and challenges. [ABSTRACT FROM AUTHOR]