Browse Articles

The effect of compositional fluctuations in a liquid Fe–O alloy on the nucleation of Earth’s inner core

Abstract The Earth’s solid inner core plays a fundamental role in determining the past and present properties and dynamics of the Earth’s deep interior. Inner core growth powers the geodynamo, producing the protective global magnetic field, and provides a record of core evolution spanning geological timescales. However, the origins of the inner core remain enigmatic. Traditional core evolution models assume that the inner core formed when the core first cooled to its melting temperature, but this neglects the physical requirement that liquids must be supercooled to below their melting point before freezing. Prior estimates from mineral physics calculations of the supercooling $$\delta T$$ required to homogeneously nucleate the inner core from candidate binary alloys exceed constraints of $$\delta T \lesssim 400$$  K inferred from geophysical observations, while a plausible scenario for heterogeneous nucleation has yet to be identified. Here we consider a different possibility, that atomic-scale compositional fluctuations can increase the local melting temperature, and hence supercooling, available for homogeneous nucleation. Using molecular dynamic simulations of Fe-O alloys we find that compositional fluctuations producing O-depleted regions are too rare to aid nucleation, while O-enriched regions can reduce the undercooling by $$\sim$$ 50 K ( $$\delta T \sim 700$$  K) for a bulk concentration of 20 mol.% O or $$\sim$$ 400 K ( $$\delta T \sim 300$$  K) for a bulk concentration of 30 mol.% O. While these results do not explain the nucleation of Earth’s inner core, they do show that compositional fluctuations can aid the process of homogeneous nucleation.

High-energy argon implantation in carbon nanowalls as a way to produce electrodes for supercapacitor applications

Fluid dynamics model of the cerebral ventricular system

Hydrocephalus, a neurological condition characterized by an excessive buildup of cerebrospinal fluid (CSF) in the brain, affects millions worldwide and leads to severe consequences. Current treatments, such as ventriculoperitoneal shunts, divert excess CSF from the brain but often face complications, mainly due to shunt obstructions caused by biological matter accumulation. While previous shunt designs aimed to improve fluid flow and reduce occlusion, they often lacked the precision needed for real-world applications due to simplified simulation models that did not fully capture the dynamics of the cerebral ventricular system. Here, we introduce BrainFlow, a computational model that integrates detailed anatomical and physiological features to simulate CSF dynamics in the presence of shunt implants. BrainFlow incorporates patient-specific medical imaging data, pulsatile flow to mimic cardiac cycles, adjustable parameters for various hydrocephalus conditions, and a biomolecule tracking feature to evaluate the long-term risk of shunt occlusion due to flow-mediated biomolecular transport. This model provides a more nuanced understanding of the factors contributing to shunt obstruction, offering insights into optimal shunt placement, design, and materials choice. Through validation against four-dimensional MRI flow data, BrainFlow demonstrates robust accuracy across multiple flow metrics. Our work lays the groundwork for the development of next-generation shunts tailored to individual patient anatomy and pathology, ultimately aiming to improve hydrocephalus treatment through informed, patient-specific design strategies.

Machine Learning simulations reveal oxygen’s phase diagram and thermal properties at conditions relevant to white dwarfs

Sintilimab and anlotinib with gemcitabine plus cisplatin in advanced biliary tract cancer: SAGC a randomized phase 2 trial

A rationally thin composite membrane with differentiated pore structure for industrial-scale alkaline water electrolysis

Generation, Capture, Storage, and Release of Singlet Oxygen from a Perylene Diimide‐Based Metallacage for Oxygen Sensing

Abstract The controlled generation and utilization of singlet oxygen ( 1 O 2 ) are crucial for its diverse applications but remain challenging due to its high reactivity and short‐lived nature. Here, we report a box‐shaped metallacage prepared via multicomponent coordination‐driven self‐assembly using tetrapyridyl perylene diimide (PDI) and tetracarboxylate anthracene as building blocks. Upon photo‐irradiation, the PDI faces act as photosensitizers to generate 1 O 2 , which reacts with the anthracene pillars to form a peroxidized metallacage, where 1 O 2 is captured and stored as anthracene peroxides. Heating releases 1 O 2 quantitatively, restoring the original metallacage structure. Both states are stable at room temperature, as confirmed by X‐ray diffraction. Additionally, photoinduced electron transfer (PET) from anthracene pillars to PDI faces quenches the emission of the metallacage, while oxidation of anthracene inhibits PET, yielding bright fluorescence for the peroxidized metallacage. This reversible emission change enables the metallacage to function as a “turn‐on” fluorescence sensor for dissolved oxygen, with a detection limit of 1.1 × 10 −3 mg L −1 . This study demonstrates a metallacage that can generate, capture, store, and release 1 O 2 for oxygen sensing, offering insights for designing stimuli‐responsive smart materials.

Efforts to link HIV-positive and high-risk blood donors to HIV testing, and treatment services, Mozambique, 2019–2020

Abstract Mozambique’s National Blood Transfusion Services (NBTS) is tasked with providing safe and available blood but also conducting systematic screening of at-risk potential donors, notifying seropositive blood donors, and linking them to HIV care and treatment services. Potential blood donors who were deferred from donating following a behavioral risk screening and all blood donors who screened seropositive for HIV were notified and offered linkage to HIV testing, care, and treatment services by community-based organizations. A prospective study among HIV-positive blood donors and deferred donors was conducted from May 2019 to July 2020 at Maputo Central Hospital Blood Bank and the National Reference Blood Center. The associations between testing, initiating care and treatment services among HIV-positive blood donors and prospective deferred donors were estimated using fully Bayesian multivariable logistic models and odds ratios. Among 885 prospective blood donors enrolled, 173 (20%) were deferred due to self-reported high-risk behaviors identified through a screening questionnaire, and 712 (80%) passed the behavioral-risk screening tool, donated, and the blood donation tested positive for HIV. There were more than 2.5 times as many male donors as female donors with a positive HIV test, and among the deferred donors, more than 84% were males. 36% (256/712) of seropositive donors and 35% (61/173) of deferred donors were referred to HIV testing services. 62% (158/256) of seropositive donors and 4.9% (3/61) of deferred donors who were successfully referred were linked to care and treatment services, and 96% (152/158) of these seropositive donors and 100% (3/3) of deferred as high-risk donors initiated antiretroviral therapy (ART). Of the three service organizations used, one outperformed the other two in linking seropositive donors to ART treatment. The NBTS can serve as a critical entry point for identifying HIV-positive persons. Improved implementation of risk behavior screening tools is needed and could contribute to early identification and initiation of ART for potential donors. Innovative strategies and solutions by community-based organizations can be used to improve blood donor notification and linkage to HIV testing and treatment services.

Oxidative potential of PM1, PM2.5, and PM10 collected in car and tram tunnels to analyse their impact on public health

Identification of spastic ataxia-related proteins via comparative proteomic analysis of the cerebellum of conditional Ankfy1 knockout mice

Abstract Ankyrin repeat and FYVE domain containing 1 (ANKFY1) is an indispensable protein in the development of cerebellar Purkinje cells. Our preliminary study revealed that its absence caused progressive spastic ataxia, accompanied by the loss of Purkinje cells in mice. Here, we generated Ankfy1-floxed (Ankfy1 f/f) mice, in which conditional inactivation of the Ankfy1 gene was achieved specifically in cerebellar Purkinje cells via crossing with a transgenic mouse strain expressing Cre recombinase under the regulatory control of the Purkinje cell protein 2 (PCP2) promoter. We employed data-independent acquisition (DIA) mass spectrometry to compare the protein expression profiles in cerebellar samples. The samples were obtained from two groups of male mice. The first group consisted of three Pcp2-Cre; Ankfy1 f/f male mice, where the Ankfy1 gene was conditionally knocked out in Purkinje cells, and these mice were designated as the conditional knockout (CKO) group. The second group included three Cre-negative; Ankfy1 f/f littermate male mice served as the wild-type (WT) control group. The results identified 69 (45 upregulated and 24 downregulated) differentially expressed proteins (DEPs) in CKO vs. WT male mice with a 1.5-fold change. Enrichment analyses of these DEPs based on the Gene Ontology (GO), Orthologous Groups of Proteins (COG), and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases revealed functional clusters associated with neuronal cell morphogenesis, extracellular structures, regulation of Rho-GTPase, calcium signaling pathway, etc. Itgb2, which was upregulated in CKO mice, was the top hub gene according to protein–protein interaction (PPI) analysis. We selected seven interesting differentially expressed genes (Arhgdib, Impa2, Pcp2, Pcp4, Ppp1r17, Rhobtb2, and Cdc123) for further validation. Arhgdib and Imp2a expression was increased in the cerebellum of CKO male and female mice, and Pcp2 and Pcp4 expression was decreased. Western blotting and immunofluorescence verified the upregulation of ARHGDIB and the downregulation of PCP2 in the cerebellum. Our proteomic analysis of conditional Ankfy1 knockout mice may guide future research to help develop treatments for progressive spastic ataxia.

MRI-derived articular cartilage strains predict patient-reported outcomes six months post anterior cruciate ligament reconstruction

Analysis of closed and open numerical systems of geochemical data in spatial statistics environment in order to separate anomalous areas

The proteome of circulating extracellular vesicles and their functional effect on platelets vary with the isolation method

Risk factors associated with health literacy among community residents in China based on multiple correspondence analysis and ordinal logistic regression

Dynamic assessment and zoning strategies for ecosystem health in Poyang lake urban agglomeration

Abstract Assessing and appropriately managing the ecosystem health of urban agglomerations are significant for safeguarding regional ecological security and sustainable development. From a spatiotemporal dynamic perspective, with the Poyang Lake urban agglomeration as a case, this study established a ‘Vigour–Organisation–Resilience–Service’ framework to assess ecosystem health, analysed spatiotemporal characteristics, identified key driving factors and their interactions contributing to spatial differentiation and ultimately adopted a ‘level–type’ zoning control strategy. The results show that: (1) From 2005 to 2022, the natural ecosystem health index declined in 14.70% of the region, with a central concentration of low values in the Poyang Lake area. The ecosystem service index decreased in 11.10% of the region but remained high in the Poyang Lake area. Varying degrees of positive spatial spillover effects were observed for both indices. (2) The average regional comprehensive ecosystem health index was 0.2914, with an overall downward trend. In the urban agglomeration, the comprehensive ecosystem health index remained stable in 78.18% of the total area, indicating a notable ‘polarisation’ in health levels among different areas. (3) Socioeconomic factors significantly influence ecosystem health in the urban agglomeration. (4) The urban agglomeration displayed distinct spatial patterns in terms of the types of changes in ecosystem health. Considering both current status and trends, zoning control and differentiated management strategies were implemented for the urban agglomeration. The approaches of differentiated management and zoning control can promote the coordinated development of the Poyang Lake urban agglomeration, facilitating a dynamic balance between urbanisation and ecological protection.

Make forensic case reports required legal and scientific documents

Isotopologue-induced structural dynamics of a triazolate metal-organic framework for efficient hydrogen isotope separation

Abstract Efficient hydrogen isotope separation remains the biggest challenge due to the nearly identical physicochemical properties of H2 and D2. Through in situ neutron powder diffraction and gas adsorption experiments, we investigate the hydrogen isotopologue-induced structural dynamics of the triazole-based metal-organic framework [Mn(ta)2]. Gas loading induces a measurable lattice expansion, more pronounced for H2 than D2, and two distinct adsorption sites are identified with a subtle but significant difference in the occupancy of H2 and D2 at 60 K. Cryogenic thermal desorption spectroscopy after exposure to a 1:1 isotope mixture reveals an exceptionally high D2/H2 selectivity of 32.5 at 60 K. When exposed to a D2/H2 mixture of 5:95, D2 enriches to 75% in a single cycle. Given the commercial availability of the ligand and the scalability of the dia-framework topology across divalent transition metals, upscaling for industrial-scale deuterium separation is a realistic prospect. Our results give crucial molecular-level insights into isotopologue-induced structural dynamics in triazolate-based MOFs and provide guidance for improvement of isotope separation materials.

The clinical effectiveness of sodium-glucose co-transporter-2 inhibitors on prognosis of patients with chronic obstructive pulmonary disease and diabetes

Microenvironment-feedback regulated hydrogels as living wound healing materials

Implied object direction from eye location enhances animacy ratings but not detection of chasing behavior

Abstract Understanding how humans perceive animacy in dynamic visual stimuli is fundamental to elucidating the mechanisms underlying visual social cognition. While both object geometry and eye-like features are known to independently influence animacy impressions, their interactive effects remain insufficiently explored. This study investigates how the combination of object geometry and the location of eye-like patterns modulates the perception of animacy in non-living moving objects. In Experiment 1, we manipulated the pointing direction of triangular objects and the location of eye-like features (near the vertex, near the edge, or absent), and found that animacy impressions were enhanced when the direction of motion aligned with the gaze-implied object direction, irrespective of the object’s geometrical shape. Experiment 2 examined whether this effect generalizes to an objective task, in which participants identify a target triangle chasing a green disk among distractors. Although the gaze-implied object direction did not significantly influence detection sensitivity, the spatial location of the eye pattern within the triangular shape continued to weakly modulate participants’ performance. These findings suggest that cues related to eye location contribute to subjective animacy at multiple stages of cognitive processing, with their impact varying depending on task demands and perceptual context.