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Despite extensive investigation, the nature and causes of the Mid-Pleistocene Transition remain enigmatic. In this work, we assess its linkage to asynchronous development of bipolar ice sheets by synthesizing Pleistocene mid- to high-latitude proxy records linked to hemispheric ice sheet evolution. Our results indicate substantial growth of the Antarctic Ice Sheets (AISs) at 2.0 to 1.25 million years ago, preceding the rapid expansion of Northern Hemisphere Ice Sheets after ~1.25 million years ago. Proxy-model comparisons suggest that AIS and associated Southern Ocean sea ice expansion can induce northern high-latitude cooling and enhanced moisture transport to the Northern Hemisphere, thus triggering the Mid-Pleistocene Transition. The dynamic processes involved are crucial for assessing modern global warming that is already inducing asynchronous bipolar melting of ice sheets.
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The clinical diagnosis of pathogen infectious diseases increasingly requires sensitive and rapid RNA detection technologies. The RNA-guided clustered regularly interspaced short palindromic repeats (CRISPR)/Cas13a system has shown immense potential in molecular diagnostics due to its trans-cleavage activity. However, most Cas13a-based detection methods require an amplicon transcription step, and the multi-step open-tube operations are prone to contamination, limiting their widespread application. Here, we propose an ultrasensitive (single-copy range, â¼aM) and rapid (within 40 min) isothermal one-pot RNA detection platform, termed SATCAS (Simultaneous Amplification and Testing platform based on Cas13a). This method effectively distinguishes viable bacteria (0%-100%) under constant total bacterial conditions, demonstrating its robustness and universality. SATCAS excels in identifying single nucleotide polymorphisms (SNPs), particularly detecting 0.5% drug-resistant mutations. We validated SATCAS by detecting infections in biological samples from 68 HBV, 23 EBV, and 48 SARS-CoV-2 patients, achieving 100% sensitivity, 92.86% specificity, and 97.06% accuracy in HBV infection testing. We anticipate that SATCAS has broad application potential in the early diagnosis, subtyping, drug resistance detection, and point-of-care monitoring of pathogen infectious diseases.
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The Atlantic circulation is a key component of the global ocean conveyor that transports heat and nutrients worldwide. Its likely weakening due to global warming has implications for climate and ecology. However, the expected changes remain largely uncertain as low-resolution climate models currently in use do not resolve small scales. Although the large-scale circulation tends to weaken uniformly in both the low-resolution and our high-resolution climate model version, we find that the small-scale circulation in the North Atlantic changes abruptly under global warming and exhibits pronounced spatial heterogeneity. Furthermore, the future Atlantic Ocean circulation in the high-resolution model version expands in conjunction with a sea ice retreat and strengthening toward the Arctic. Finally, the cutting-edge climate model indicates sensitive shifts in the eddies and circulation on regional scales for future warming and thus provides a benchmark for next-generation climate models that can get rid of parametrizations of unresolved scales.
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Under transient greenhouse warming, El Niño-Southern Oscillation (ENSO) is projected to increase pre-2100, accompanied by an easier establishment of atmospheric convection in the equatorial eastern Pacific, where sea surface temperature (SST) warms faster than surrounding regions. After 2100, how ENSO variability may change remains unknown. Here we find that under a high emission scenario, ENSO variability post-2100 reverses from the initial increase to an amplitude far smaller than that of the 20th century. The fast eastern warming persists and shrinks the equatorial Pacific non-convective area, such that establishing convection in the non-convective area, as during an El Niño, requires smaller convective anomaly, inducing weaker wind anomalies leading to reduced ENSO SST variability. The nonlinear ENSO response is thus a symptom of the persistent El Niño-like warming pattern. Therefore, the oscillatory ENSO impact could be replaced by that from the permanent El Niño-like mean condition with cumulative influences on affected regions.
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Results of measurable residual disease (MRD)-testing by next-generation sequencing (NGS) correlate with relapse risk in adults with B-cell acute lymphoblastic leukemia (ALL) receiving chemotherapy or an allotransplant from a human leukocyte antigen (HLA)-identical relative or HLA-matched unrelated donor. We studied cumulative incidence of relapse (CIR) and survival prediction accuracy using a NGS-based MRD-assay targeting immunoglobulin genes after 2 courses of consolidation chemotherapy cycles in 93 adults with B-cell ALL most receiving HLA-haplotype-matched related transplants. Prediction accuracy was compared with MRD-testing using multi-parameter flow cytometry (MPFC). NGS-based MRD-testing detected residual leukemia in 28 of 65 subjects with a negative MPFC-based MRD-test. In Cox regression multi-variable analyses subjects with a positive NGS-based MRD-test had a higher 3-year CIR (Hazard Ratio [HR] = 3.37; 95 % Confidence Interval [CI], 1.34-8.5; P = 0.01) and worse survival (HR = 4.87 [1.53-15.53]; P = 0.007). Some data suggest a lower CIR and better survival in NGS-MRD-test-positive transplant recipients but allocation to transplant was not random. Our data indicate MRD-testing by NGS is more accurate compared with testing by MPFC in adults with B-cell ALL in predicting CIR and survival. (Registered in the Beijing Municipal Health Bureau Registration N 2007-1007 and in the Chinese Clinical Trial Registry [ChiCTR-OCH-10000940 and ChiCTROPC-14005546]).
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Upwelling along oceanic eastern boundaries has attracted significant attention due to its profound effects on ocean productivity and associated biological and socioeconomic implications. However, uncertainty persists regarding the evolution of coastal upwelling with climate change, particularly its impact on future biological production. Here, using a series of state-of-the-art climate models, we identify a significant seasonal advancement and prolonged duration of upwelling in major upwelling systems. Nevertheless, the upwelling intensity (total volume of upwelled water) exhibits complex changes in the future. In the North Pacific, the upwelling is expected to attenuate, albeit with a minor magnitude. Conversely, in other basins, coastal upwelling diminishes significantly in equatorward regions but displays a slight decline or even an enhancement at higher latitudes. The climate simulations also reveal a robust connection between changes in upwelling intensity and net primary production, highlighting the crucial impact of future coastal upwelling alterations on marine ecosystems.
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Mudança Climática , Ecossistema , Água do Mar/química , Oceanos e Mares , Estações do Ano , Modelos Climáticos , Oceano Pacífico , Movimentos da ÁguaRESUMO
A new class of amphiphilic tetradentate platinum(ii) Schiff base complexes has been designed and synthesized. The self-assembly properties by exploiting the potential Ptâ¯Pt interactions of amphiphilic platinum(ii) Schiff base complexes in the solution state have been systematically investigated. The presence of Ptâ¯Pt interactions has further been supported by computational studies and non-covalent interaction (NCI) analysis of the dimer of the complex. The extent of the non-covalent Ptâ¯Pt and π-π interactions could be regulated by a variation of the solvent compositions and the hydrophobicity of the complexes, which is accompanied by attractive spectroscopic and luminescence changes and leads to diverse morphological transformations. The present work represents a rare example of demonstration of directed cooperative assembly of amphiphilic platinum(ii) Schiff base complexes by intermolecular Ptâ¯Pt interactions in solution with an in-depth mechanistic investigation, providing guiding principles for the construction of supramolecular structures with desirable properties using platinum(ii) Schiff base building blocks.
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Skin-interfaced wearable sensors can continuously monitor various biophysical and biochemical signals for health monitoring and disease diagnostics. However, such devices are typically limited by unsatisfactory and unstable output performance of the power supplies under mechanical deformations and human movements. Furthermore, there is also a lack of a simple and cost-effective fabrication technique to fabricate and integrate varying materials in the device system. Herein, we report a fully integrated standalone stretchable biophysical sensing system by combining wearable biophysical sensors, triboelectric nanogenerator (TENG), microsupercapacitor arrays (MSCAs), power management circuits, and wireless transmission modules. All of the device components and interconnections based on the three-dimensional (3D) networked graphene/Co3O4 nanocomposites are fabricated via low-cost and scalable direct laser writing. The self-charging power units can efficiently harvest energy from body motion into a stable and adjustable voltage/current output to drive various biophysical sensors and wireless transmission modules for continuously capturing, processing, and wirelessly transmitting various signals in real-time. The novel material modification, device configuration, and system integration strategies provide a rapid and scalable route to the design and application of next-generation standalone stretchable sensing systems for health monitoring and human-machine interfaces.
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Cobalto , Grafite , Lasers , Nanocompostos , Óxidos , Dispositivos Eletrônicos Vestíveis , Grafite/química , Nanocompostos/química , Óxidos/química , Cobalto/química , Porosidade , Humanos , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Tecnologia sem FioRESUMO
Patterns of sea surface temperature (SST) anomalies of the Indian Ocean Dipole (IOD) exhibit strong diversity, ranging from being dominated by the western tropical Indian Ocean (WTIO) to the eastern tropical Indian Ocean (ETIO). Whether and how the different types of IOD variability patterns affect the variability of Antarctic sea ice is not known, nor is how the impact may change in a warming climate. Here, we find that the leading mode of austral spring Antarctic sea ice variability is dominated by WTIO SST variability rather than ETIO SST or El Niño-Southern Oscillation. WTIO warm SST anomalies excite a poleward-propagating Rossby wave, inducing a tri-polar anomaly pattern characterized by a decrease in sea ice near the Amundsen Sea but an increase in regions on both sides. Such impact has been weakening in the two decades post-2000, accompanied by weakened WTIO SST variability. Under greenhouse warming, climate models project a decrease in WTIO SST variability, suggesting that the reduced impact on Antarctic sea ice from the IOD will likely to continue, facilitating a fast decline of Antarctic sea ice.
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Digital light processing (DLP) techniques are widely employed in various engineering and design fields, particularly additive manufacturing. Acrylate resins utilized in DLP processes are well known for their versatility, which enables the production of defect-free 3D-printed products with excellent mechanical properties. This study aims to improve the mechanical and thermal properties of 3D-printed samples by incorporating mica as an inorganic filler at different concentrations (5%, 10%, and 15%) and optimizing the dispersion by adding a KH570 silane coupling agent. In this study, mica was introduced as a filler and combined with epoxy acrylate resin to fabricate a 3D-printed sample. Varying concentrations of mica (5%, 10%, and 15% w/w) were mixed with the epoxy acrylate resin at a concentration of 10%, demonstrating a tensile strength increase of 85% and a flexural strength increase of 132%. Additionally, thermal characteristics were analyzed using thermogravimetric analysis (TGA), and successful morphological investigations were conducted using scanning electron microscopy (SEM). Digital light-processing technology was selected for its printing accuracy and cost-effectiveness. The results encompass comprehensive studies of the mechanical, thermal, and morphological aspects that contribute to the advancement of additive manufacturing technology.
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B cell acute lymphoblastic leukemia (ALL) is characterized by the highly heterogeneity of pathogenic genetic background, and there are still approximately 30-40% of patients without clear molecular markers. To identify the dysregulated genes in B cell ALL, we screened 30 newly diagnosed B cell ALL patients and 10 donors by gene expression profiling chip. We found that ECM1 transcription level was abnormally elevated in newly diagnosed B cell ALL and further verified in another 267 cases compared with donors (median, 124.57% vs. 7.14%, P < 0.001). ROC analysis showed that the area under the curve of ECM1 transcription level at diagnosis was 0.89 (P < 0.001). Patients with BCR::ABL1 and IKZF1 deletion show highest transcription level (210.78%) compared with KMT2A rearrangement (39.48%) and TCF3::PBX1 rearrangement ones (30.02%) (all P < 0.05). Also, the transcription level of ECM1 was highly correlated with the clinical course, as 20 consecutive follow-up cases indicated. The 5-year OS of patients (non-KMT2A and non-TCF3::PBX1 rearrangement) with high ECM1 transcription level was significantly worse than the lower ones (18.7% vs. 72.9%, P < 0.001) and high ECM1 transcription level was an independent risk factor for OS (HR = 5.77 [1.75-19.06], P = 0.004). After considering transplantation, high ECM1 transcription level was not an independent risk factor, although OS was still poor (low vs. high, 71.1% vs. 56.8%, P = 0.038). Our findings suggested that ECM1 may be a potential molecular marker for diagnosis, minimal residual disease (MRD) monitoring, and prognosis prediction of B cell ALL.Trial registration Trial Registration Registered in the Beijing Municipal Health Bureau Registration N 2007-1007 and in the Chinese Clinical Trial Registry [ChiCTR-OCH-10000940 and ChiCTR-OPC-14005546]; http://www.chictr.org.cn .
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Leucemia-Linfoma Linfoblástico de Células Precursoras B , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras B/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Prognóstico , Biomarcadores , Fatores de Risco , Proteínas da Matriz Extracelular/genéticaRESUMO
Dynamic reversible noncovalent interactions make supramolecular framework (SF) structures flexible and designable. A three-dimensional (3D) growth of such frameworks is beneficial to improve the structure stability while maintaining unique properties. Here, through the ionic interaction of the polyoxometalate cluster, coordination of zinc ions with cationic terpyridine, and hydrogen bonding of grafted carboxyl groups, the construction of a 3D SF at a well-crystallized state is realized. The framework can grow in situ on the Zn surface, further extending laterally into a full covering without defects. Relying on the dissolution and the postcoordination effects, the 3D SF layer is used as an artificial solid electrolyte interphase to improve the Zn-anode performance. The uniformly distributed clusters within nanosized pores create a negatively charged nanochannel, accelerating zinc ion transfer and homogenizing zinc deposition. The 3D SF/Zn symmetric cells demonstrate high stability for over 3000 h at a current density of 5 mA cm-2.
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Submesoscale fronts, with horizontal scale of 0.1-10 km, are key components of climate system by driving intense vertical transports of heat, salt and nutrients in the ocean. However, our knowledge on how large the vertical transport driven by one single submesoscale front can reach remains limited due to the lack of comprehensive field observations. Here, based on high-resolution in situ observations in the Kuroshio-Oyashio Extension region, we detect an exceptionally sharp submesoscale front. The oceanic temperature (salinity) changes sharply from 14 °C (34.55 psu) to 2 °C (32.7 psu) within 2 km across the front from south to north. Analysis reveals intense vertical velocities near the front reaching 170 m day-1, along with upward heat transport up to 1.4 × 10-2 °C m s-1 and salinity transport reaching 4 × 10-4 psu m s-1. The observed heat transport is much larger than the values reported in previous observations and is three times as that derived from current eddy-rich climate models, whereas the salinity transport enhances the nutrients concentration with prominent implications for marine ecosystem and fishery production. These observations highlight the vertical transport of submesoscale fronts and call for a proper representation of submesoscale processes in the next generation of climate models.
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Generally, thin-layer chromatography always undertakes the indispensable role in rapid screening and identification of specific compounds. Stationary phase is the core part of thin-layer chromatography with fixed property, which leading to the limitations of separation mode of only regulating the composition of mobile phase. This work was an attempt to fabricate the unique photosensitive thin-layer chromatography to make up the above major drawback. 4-[3-(Triethoxysilyl)propoxy]azobenzene (azo-PTES) was synthesized as photosensitive modifier to fabricate the photosensitive stationary phase, and the transformation of cis-trans structure of azo-PTES proceeds along with polarity difference under 365 nm and 473 nm irradiation. Based on this, the proposed photosensitive thin-layer chromatography shows the reversible switch of polarity of stationary phase by photoinduction, followed by the deserved reversible separation behavior. Furthermore, multi-regulation in spatial dimension was achieved based on the high freedom of spatial regulation of photoinduction, which brings about the integration of stationary phase with different polarity, just by photoinduction. The concept of photosensitive thin-layer chromatography provides new idea for improving separation efficiency and developing multi-dimensional thin-layer chromatography on the one plate.
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Objective: We aimed to explore the feasibility of lung ultrasound for perioperative assessment and the optimal effect of lung ultrasound in reducing lung complications during non-cyanotic congenital heart disease (CHD) surgery using ultrafast-track anesthesia. Methods: Sixty patients were treated at Shenzhen Children's Hospital between 2019 and 2020. Of these, 30 patients in group N had an indication for extubation and ultrafast-track anesthesia after congenital heart surgery; the tracheal catheter was removed, and the patients were sent to the cardiac intensive care unit (CICU) for further monitoring and treatment. Another 30 patients were in group L and also had an indication for extubation and ultrafast-track anesthesia; in addition we compared lung ultrasound score (LUS) before and after surgery, when we found the cases that LUS ≥ 15, for whom targeted optimization treatment would be carried out. The tracheal catheter was removed after LUS <15 days before the patients were sent to the CICU. In all cases, the LUS and PaO2/FiO2 ratios (P/F) of both groups were recorded at the time of anesthesia induction (T0), before extubation (T1), and 5 min (T2), 1 h (T3), and 24 h (T4) after extubation. The incidence of pulmonary complications, LUS, and P/F were compared between the two groups. Results: There was great consistency between LUS and radiographic findings. Comparing the data of the two groups at T2, T3 and T4, the P/F was higher and the LUS was lower in group L than in group N. The incidence of lung complications in group L (18 cases, 60 %) was lower than that in group N (26 cases, 86.7 %, χ2 = 5.46, P = 0.02); comparing LUS between T0 and T3, LUS decreased in a greater number of cases in group L (15, 50 %) than in group N (7 cases, 23.3 %, χ2 = 4.59, P = 0.032). Conclusion: Lung ultrasonography can effectively help assess lung conditions. Optimization guided by lung ultrasound in ultrafast track anesthesia can significantly reduce postoperative lung complications.
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Ion-conducting membranes (ICMs) with high selectivity are important components in redox flow batteries. However it is still a challenge to break the trade-off between ion conductivity and ion selectivity, which can be resolved by the regulation of their nanostructures. Here, polyoxometalate (POM)-hybridized block copolymers (BCPs) are used as self-assembled additives to construct proton-selective nanobarriers in the ICM matrix to improve the microscopic structures and macroscopic properties of ICMs. Benefiting from the co-assembly behavior of BCPs and POMs and their cooperative noncovalent interactions with the polymer matrix, â¼50 nm ellipsoidal functional nanoassemblies with hydrophobic vanadium-shielding cores and hydrophilic proton-conducting shells are constructed in the sulfonated poly(ether ether ketone) matrix, which leads to an overall enhancement of proton conductivity, proton selectivity, and cell performance. These results present a self-assembly route to construct functional nanostructures for the modification of polymer electrolyte membranes toward emerging energy technologies.
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Polymer-based dielectric composites are of great importance in advanced electronic industries and energy storage because of their high dielectric constant, good processability, low weight, and low dielectric loss. FDM (Fused Deposition Modeling) is a greatly accessible additive manufacturing technology, which has a number of applications in the fabrication of RF components, but the unavoidable porosity in FDM 3D-printed materials, which affects the dielectric properties of the materials, and the difficulty of large-scale fabrication of composites by FDM limit its application scope. This study's main focus is on how the matrix, filler, interface, and FDM 3D printing parameters influence the electrical properties of FDM-printed polymer-based dielectric composites. This review article starts with the fundamental theory of dielectrics. It is followed by a summary of the factors influencing dielectric properties in recent research developments, as well as a projection for the future development of FDM-prepared polymer-based dielectric composites. Finally, improving the comprehensive performance of dielectric composites is an important direction for future development.
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A two-dimensional supramolecular framework with a tetragonal structure is constructed via host-guest interaction of a pillar[5]arene grafted polyanion with a modified porphyrin. The membrane of the framework with a chiral counterion exhibits enantiomeric selectivity during the filtration of racemic molecules with amino groups, demonstrating broadened potential in chiral separations.
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Additive manufacturing of carbon-fiber-reinforced polymer (CFRP) has been widely used in many fields. However, issues such as inconsistent fiber orientation distribution and void formation during the layer stacking process have hindered the further optimization of the composite material's performance. This study aimed to address these challenges by conducting a comprehensive investigation into the influence of carbon fiber content and printing parameters on the micro-morphology, thermal properties, and mechanical properties of PA6-CF composites. Additionally, a heat treatment process was proposed to enhance the interlayer bonding and tensile properties of the printed composites in the printing direction. The experimental results demonstrate that the PA6-CF25 composite achieved the highest tensile strength of 163 MPa under optimal heat treatment conditions: 120 °C for 7.5 h. This corresponds to a significant tensile strength enhancement of 406% compared to the unreinforced composites, which represents the highest reported improvement in the current field of CFRP-fused deposition 3D printing. Additionally, we have innovatively developed a single-layer monofilament CF-OD model to quantitatively analyze the influence of fiber orientation distribution on the properties of the composite material. Under specific heat treatment conditions, the sample exhibits an average orientation angle µ of 0.43 and an orientation angle variance of 8.02. The peak frequency of fiber orientation closely aligns with 0°, which corresponds to the printing direction. Finally, the study explored the lightweight applications of the composite material, showcasing the impressive specific energy absorption (SEA) value of 17,800 J/kg when implementing 3D-printed PA6-CF composites as fillers in automobile crash boxes.
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In underwater acoustic (UWA) communications, channels often exhibit a clustered-sparse structure, wherein most of the channel impulse responses are near zero, and only a small number of nonzero taps assemble to form clusters. Several algorithms have used the time-domain sparse characteristic of UWA channels to reduce the complexity of channel estimation and improve the accuracy. Employing the clustered structure to enhance channel estimation performance provides another promising research direction. In this work, a deep learning-based channel estimation method for UWA orthogonal frequency division multiplexing (OFDM) systems is proposed that leverages the clustered structure information. First, a cluster detection model based on convolutional neural networks is introduced to detect the cluster of UWA channels. This method outperforms the traditional Page test algorithm with better accuracy and robustness, particularly in low signal-to-noise ratio conditions. Based on the cluster detection model, a cluster-aware distributed compressed sensing channel estimation method is proposed, which reduces the noise-induced errors by exploiting the joint sparsity between adjacent OFDM symbols and limiting the search space of channel delay spread. Numerical simulation and sea trial results are provided to illustrate the superior performance of the proposed approach in comparison with existing sparse UWA channel estimation methods.