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The investigation of triggers causing the onset and intensification of Northern Hemisphere Glaciation (NHG) during the late Pliocene is essential for understanding the global climate system, with important implications for projecting future climate changes. Despite their critical roles in the global climate system, influences of land-ocean interactions on high-latitude ice sheets remain largely unexplored. Here, we present a high-resolution Asian dust record from Ocean Drilling Program Site 1208 in the North Pacific, which lies along the main route of the westerlies. Our data indicate that atmosphere-land-ocean interactions affected aeolian dust emissions through modulating moisture and vegetation in dust source regions, highlighting a critical role of terrestrial systems in initiating the NHG as early as 3.6 Myr ago. Combined with additional multi-proxy and model results, we further show that westerly wind strength was enhanced, mainly at low-to-middle tropospheric levels, during major glacial events at about 3.3 and 2.7 Myr ago. We suggest that coupled responses of Earth's surface dynamics and atmospheric circulation in the Plio-Pleistocene likely involved feedbacks related to changes in paleogeography, ocean circulation, and global climate.
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OBJECTIVE: Fibular length is important for ankle stability. Failure to adequately restore and stabilize fibula length may result in malunion, hindering postoperative functional exercises and recovery of ankle function. However, there is no unified and effective reduction method for fibular shortening in Maisonneuve fractures. In this study, we introduce the biplane reduction as an effective surgical technique for restoring the length of the fibula in Maisonneuve fractures. METHODS: This retrospective study enrolled 12 patients preoperatively diagnosed with Maisonneuve fractures between June 2019 and June 2022. All patients underwent our biplane reduction technique to restore the length of their fibula. Operation time, hospital stay, complications, FTA (the angle between the fibular tip and the superior articular surface of the talus), visual analog pain score, and the American Orthopaedic Foot and Ankle Society ankle-hindfoot score were recorded. An independent sample t-test was used for component comparisons, and a paired sample t-test or one-way analysis of variance was used for intra-group comparisons. RESULTS: No patient was lost to follow-up and no obvious postoperative complications were observed. After operation, FTA recovered from 37.52 ± 0.37 ° to 40.42 ± 0.43 °, which was significantly improved compared with that before operation (p < 0.01). At the last follow-up, both the VAS and AOFAS scores showed significant improvement compared to pre-surgery scores. CONCLUSIONS: The reduction technique proposed in this study to restore the length of the fibula in Maisonneuve fractures is simple and effective, does not require special equipment, and has the advantage of directly examining the reduction condition.
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The present study investigates the efficacy of newly developed Zr-based metal-organic frameworks, specifically MIP-206, and its amine-modified counterpart, MIP-206-NH2, for the re-covery of antimony (Sb) from both synthetic and actual mining wastewater. Batch method studies were employed to examine the effect of waste media pH, Sb concentration, process kinetics, and the performance of the regeneration solution. MIP-206-NH2 exhibited impressive separation capabilities, achieving 102.18 mg/g and 63.23 mg/g for Sb (V) and Sb (III), respectively. In contrast, the pristine MIP-206 reached maximum values of 26.26 mg/g for Sb (V) and 16.95 mg/g for Sb (III). The separation process was well-described by the Langmuir equation, and the kinetics followed the pseudo-second-order model. Although the amine modification resulted in a decrease in the surface area of MIP-206 from 1345.21 to 1169.86 m2/g, SEM and XRD analyses confirmed that the structural integrity of MIP-206-NH2 remained unchanged. In terms of reusability, MIP-206-NH2 maintained up to 90% of its separation performance over 9 cycles, while MIP-206 demonstrated effectiveness for 7 cycles. The regeneration solution exhibited a capacity of approximately 0.63 mol/L for Sb (V) and 0.71 mol/L for Sb (III). Furthermore, MIP-206 and MIP-206-NH2 demonstrated successful application in selectively separating Sb from real mining wastewater.
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Elucidating molecular-level interactions between dihydrogen (H2) and uranium oxides reveals fundamental insights into the intrinsic H2 activation mechanisms underlying processes such as heterogeneous catalysis over uranium oxides and corrosion of uranium induced by H2. Herein, the reactions of H2 with uranium monoxide (UO) molecules have been investigated via a combination of matrix-isolation infrared spectroscopy and quantum chemical calculations. A side-on bonded H2 complex, OU(η2-H2), is identified at 3733.7 and 800.3 cm-1. This species is regarded as a crucial intermediate along H2 activation pathways. Bonding analysis reveals cooperative U(π5f/6d) â H2(σ*) π// backdonation and U â H2(σ) σ donation in OU(η2-H2) that facilitate the activation of the H2 moiety. Upon λ > 550 nm photoirradiation, OU(η2-H2) isomerizes into H2UO, indicating the homolytic H2 cleavage on UO. Mechanistic details of H2 adsorption and dissociation on UO molecules have been further elucidated.
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BACKGROUND: To explore the correlation between short-chain fatty acids (SCFAs) in the peri-implant sulcular fluid (PISF) and peri-implant diseases. METHODS: PISF samples were obtained from implants that have been placed for at least 5 years, and peri-implant clinical parameters were examined. Gas chromatography-mass spectrometry and high-performance liquid chromatography were used to detect SCFAs in PISF. The correlation between SCFAs and clinical parameters was analyzed by Spearman's correlation. SCFAs related to peri-implant disease were identified by logistic regression and ranked by random forest analysis. RESULTS: Eighty-six implants were divided into a peri-implant health group (PIH-group, 35 implants), peri-implant mucositis group (PIM-group, 25 implants), and peri-implantitis group (PI-group, 26 implants) according to clinical and radiographic examination results. The PIM-group had significantly lower formic acid detection rate than the other two groups (p < 0.001). The PIM-group had significantly higher levels of acetic, propionic, and isovaleric acids than the PIH-group (p < 0.05). The PI-group had significantly higher levels of propionic, butyric, isobutyric, valeric, and isovaleric acids than the PIH-group (p < 0.05). The PI-group had significantly higher levels of butyric, isobutyric, and isovaleric acids than the PIM-group (p < 0.05). SCFAs (apart from hexanoic and succinic acids) were significantly and positively correlated with clinical parameters (p < 0.05). SCFAs related to peri-implant disease were ranked as follows: butyric, isovaleric, isobutyric, propionic, acetic, formic, and lactic acids. CONCLUSIONS: Elevated specific SCFAs are correlated with peri-implant disease. Recognition of this correlation may help in early identification of peri-implant disease and guide further clinical interventions.
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This paper introduces a novel bounded loss framework for SVM and SVR. Specifically, using the Pinball loss as an illustration, we devise a novel bounded exponential quantile loss (Leq-loss) for both support vector machine classification and regression tasks. For Leq-loss, it not only enhances the robustness of SVM and SVR against outliers but also improves the robustness of SVM to resampling from a different perspective. Furthermore, EQSVM and EQSVR were constructed based on Leq-loss, and the influence functions and breakdown point lower bounds of their estimators are derived. It is proved that the influence functions are bounded, and the breakdown point lower bounds can reach the highest asymptotic breakdown point of 1/2. Additionally, we demonstrated the robustness of EQSVM to resampling and derived its generalization error bound based on Rademacher complexity. Due to the Leq-loss being non-convex, we can use the concave-convex procedure (CCCP) technique to transform the problem into a series of convex optimization problems and use the ClipDCD algorithm to solve these convex optimization problems. Numerous experiments have been conducted to confirm the effectiveness of the proposed EQSVM and EQSVR.
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Algoritmos , Máquina de Vectores de Soporte , Redes Neurales de la ComputaciónRESUMEN
Efficient topical drug delivery remains a significant challenge in glaucoma management. Although nanoparticle formulations offer considerable promise, their complex preparation processes, co-delivery issues, and batch consistency have hindered their potential. A scalable fabrication strategy is developed here for preparing solid drug nanoparticles (SDNs) with enhanced drug delivery efficiency. Utilizing hydrophobic antiglaucoma drugs brimonidine (BM) and betaxolol (BX), uniform fixed combination BM/BX SDNs are fabricated through a continuous process, improving batch-to-batch consistency for combined glaucoma treatment. With trehalose being used as a lyoprotectant, BM/BX SDNs can be stored as dry powder and easily reconstituted in phosphate buffered saline. Importantly, reconstituted BM/BX SDNs form clear, homogenous solutions, and exhibit negligible cytotoxicity and irritation, making them well-suited for topical administration as eyedrops. Ex vivo and in vivo studies demonstrated that topically applied BM/BX SDNs permeate through the cornea significantly (about two fold to three fold) compared to their hydrophilic counterparts, i.e., brimonidine tartrate, and betaxolol hydrogen chloride. Notably, BM/BX SDNs displayed consistent intraocular pressure lowering effects in vivo in both normotensive rats and glaucoma mice. Collectively, this study demonstrates the potential of the scalable fabrication strategy and the resultant BM/BX SDNs for improving glaucoma management through eyedrops.
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Array configuration design is a critical issue for a high quality of the snapshot point spread function (PSF) and restored image in Michelson imaging interferometer. In classic design, the optimized configurations usually address the few specifications and single objective, which is unable to balance the requirements of both non-redundancy and sampling distribution. In this paper, we formalize mathematically the composite metric to trade-off the multiple demands of observation, and propose the hybrid-index-based array layout optimization strategy. The simulation results demonstrate that, in comparison with the typical distribution, the optimized array using the proposed optimization framework enables the acquisition of more comprehensive spectrum information while utilizing an equal number of apertures, providing superior imaging quality in different observation situations. Furthermore, the designed optimized array masks and the compared conventional array masks were fabricated and used for our experimental validation, further verifying the feasibility of this strategy. This array configuration optimization framework may not only find applications to Michelson interferometric imaging, but also provide a positive impact on all u-v sampling-based imaging modes, including radio interferometry, magnetic resonance imaging, and photonic integrated interferometric imaging.
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Polyriboinosinic acid-polyribocytidylic acid (Poly I:C) serves as a synthetic mimic of viral double-stranded dsRNA, capable of inducing apoptosis in numerous cancer cells. Despite its potential, therapeutic benefits, the application of Poly I:C has been hindered by concerns regarding toxicity, stability, enzymatic degradation, and undue immune stimulation, leading to autoimmune disorders. To address these challenges, encapsulation of antitumor drugs within delivery systems such as cationic liposomes is often employed to enhance their efficacy while minimizing dosages. In this study, we investigated the potential of cationic liposomes to deliver Poly I:C into the Head and Neck 12 (HN12) cell line to induce apoptosis in the carcinoma cells and tumor model. Cationic liposomes made by the hydrodynamic focusing method surpass traditional methods by offering a continuous flow-based approach for encapsulating genes, which is ideal for efficient tumor delivery. DOTAP liposomes efficiently bind Poly I:C, confirmed by transmission electron microscopy images displaying their spherical morphology. Liposomes are easily endocytosed in HN12 cells, suggesting their potential for therapeutic gene and drug delivery in head and neck squamous carcinoma cells. Activation of apoptotic pathways involving MDA5, RIG-I, and TLR3 is evidenced by upregulated caspase-3, caspase-8, and IRF3 genes upon endocytosis of Poly(I:C)-encapsulated liposomes. Therapeutic evaluations revealed significant inhibition of tumor growth with Poly I:C liposomes, indicating the possibility of MDA5, RIG-I, and TLR3-induced apoptosis pathways via Poly I:C liposomes in HN12 xenografts in J:NU mouse models. Comparative histological analysis underscores enhanced cell death with Poly I:C liposomes, warranting further investigation into the precise mechanisms of apoptosis and inflammatory cytokine response in murine models for future research.
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Disruption of the circadian clock can affect starvation resistance, but the molecular mechanism is still unclear. Here, we found that starvation resistance was significantly reduced in the core gene BmPer deficient mutant silkworms (Per-/-), but the mutant's starvation resistance increased with larval age. Under natural physiological conditions, the weight of mutant 5th instar larvae was significantly increased compared to wild type, and the accumulation ability of triglycerides and glycogen in the fat bodies was upregulated. However, under starvation conditions, the weight consumption of mutant larvae was increased and cholesterol utilization was intensified. Transcriptome analysis showed that beta-oxidation was significantly upregulated under starvation conditions, fatty acid synthesis was inhibited, and the expression levels of genes related to mitochondrial function were significantly changed. Further investigations revealed that the redox balance, which is closely related to mitochondrial metabolism, was altered in the fat bodies, the antioxidant level was increased, and the pentose phosphate pathway, the source of reducing power in cells, was activated. Our findings suggest that one of the reasons for the increased energy burden observed in mutants is the need to maintain a more robust redox balance in metabolic tissues. This necessitates the diversion of more glucose into the pentose phosphate pathway to ensure an adequate supply of reducing power.
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Engineered nanoparticles (ENPs) have been increasingly used in agricultural operations, leading to an urgent need for robust methods to analyze co-occurring ENPs in plant tissues. In response, this study advanced the simultaneous extraction of coexisting silver, cerium oxide, and copper oxide ENPs in lettuce shoots and roots using macerozyme R-10 and analyzed them by single-particle inductively coupled plasma-mass spectrometry (ICP-MS). Additionally, the standard stock suspensions of the ENPs were stabilized with citrate, and the long-term stability (up to 5 months) was examined for the first time. The method performance results displayed satisfactory accuracies and precisions and achieved low particle concentration and particle size detection limits. Significantly, the oven drying process was proved not to impact the properties of the ENPs; therefore, oven-dried lettuce tissues were used in this study, which markedly expanded the applicability of this method. This robust methodology provides a timely approach to characterize and quantify multiple coexisting ENPs in plants.
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Lactuca , Espectrometría de Masas , Nanopartículas del Metal , Raíces de Plantas , Nanopartículas del Metal/química , Lactuca/química , Espectrometría de Masas/métodos , Raíces de Plantas/química , Cobre/análisis , Brotes de la Planta/química , Plata/química , Cerio/química , Tamaño de la PartículaRESUMEN
This paper employs a unique data set to analyze the trading behavior of wealthy individual investors across Mainland China and their impact on Chinese stock markets' tail risk. Results show that the wealthy individual investors' trading behavior can explain Chinese stock markets' tail risk, and the daily investment portfolios based on the network density of wealthy individual investors have significant excess returns. This paper also investigates the determinants of wealthy individual investors' trading behavior with the social network method and the spatial econometric model, and reveals that wealthy individuals benefit from the spillover effect of their trading behavior through the investor networks. The results of this paper not only reveal micro evidence for the formation mechanism of asset prices, but also provide insight into the behavior of wealthy individual investors.
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Inversiones en Salud , Inversiones en Salud/economía , China , Humanos , Modelos Económicos , Comercio/economía , Modelos EconométricosRESUMEN
Nine jatrophane diterpenoids were isolated from the whole plant Euphorbia helioscopia, including two new ones, helioscopnins A (1) and B (2). Comprehensive spectroscopic data analysis and ECD calculations elucidated their structures, including absolute configurations. All compounds were evaluated for bioactivity towards autophagic flux by flow cytometry using HM mCherry-GFP-LC3 cells. Compounds 1, 3, 4, 5, 8, and 9 significantly increased autophagic flux.
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Autofagia , Diterpenos , Euphorbia , Euphorbia/química , Diterpenos/farmacología , Diterpenos/química , Diterpenos/aislamiento & purificación , Autofagia/efectos de los fármacos , Estructura Molecular , HumanosRESUMEN
In this paper, the fused graphical lasso (FGL) method is used to estimate multiple precision matrices from multiple populations simultaneously. The lasso penalty in the FGL model is a restraint on sparsity of precision matrices, and a moderate penalty on the two precision matrices from distinct groups restrains the similar structure across multiple groups. In high-dimensional settings, an oracle inequality is provided for FGL estimators, which is necessary to establish the central limit law. We not only focus on point estimation of a precision matrix, but also work on hypothesis testing for a linear combination of the entries of multiple precision matrices. We apply a de-biasing technology, which is used to obtain a new consistent estimator with known distribution for implementing the statistical inference, and extend the statistical inference problem to multiple populations. The corresponding de-biasing FGL estimator and its asymptotic theory are provided. A simulation study and an application of the diffuse large B-cell lymphoma data show that the proposed test works well in high-dimensional situation.
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Algoritmos , Humanos , Linfoma de Células B Grandes Difuso , Modelos Estadísticos , Simulación por ComputadorRESUMEN
Drug repurposing uses approved drugs as candidate anticancer therapeutics, harnesses previous research and development efforts, and benefits from available clinically suitable formulations and evidence of patient tolerability. In this work, the drug used clinically to treat chronic alcoholism, disulfiram (DSF), was studied for its antitumor efficacy in a copper-dependent manner. The combination of DSF and copper could achieve a tumor cell growth inhibition effect comparable to those of 5-fluorouracil and taxol on head and neck cancer cells. Both bulk dendrimer hydrogel and microsized dendrimer hydrogel particles were utilized for the localized sustained release of copper in the tumor site. The localized sustained release of copper facilitated the tumor inhibition effect following intratumoral injection in a mouse's head and neck cancer model.
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Cobre , Preparaciones de Acción Retardada , Disulfiram , Neoplasias de Cabeza y Cuello , Disulfiram/farmacología , Disulfiram/química , Disulfiram/administración & dosificación , Animales , Cobre/química , Cobre/farmacología , Ratones , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/patología , Humanos , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacología , Línea Celular Tumoral , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/administración & dosificación , Ensayos Antitumor por Modelo de Xenoinjerto , Ratones DesnudosRESUMEN
Hypoxia is a prevalent characteristic of numerous neurological disorders including stroke, Alzheimer's disease, and Parkinson's disease. Extracellular vesicles (EVs) are minute particles released by cells that contain diverse biological materials, including proteins, lipids, and nucleic acids. They have been implicated in a range of physiological and pathological processes including intercellular communication, immune responses, and disease progression. EVs are believed to play a pivotal role in modulating the microenvironment of hypoxia-associated neurological diseases. These EVs are capable of transporting hypoxia-inducible factors such as proteins and microRNAs to neighboring or remote cells, thereby influencing their behavior. Furthermore, EVs can traverse the blood-brain barrier, shielding the brain from detrimental substances in the bloodstream. This enables them to deliver their payload directly to the brain cells, potentially intensifying the effects of hypoxia. Nonetheless, the capacity of EVs to breach the blood-brain barrier presents new opportunities for drug delivery. The objective of this study was to elucidate the role of EVs as mediators of information exchange during tissue hypoxia, a pathophysiological process in ischemic stroke and malignant gliomas. We also investigated their involvement in the progression and regression of major diseases of the central nervous system, which are pertinent to the development of therapeutic interventions for neurological disorders.
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Vesículas Extracelulares , Humanos , Vesículas Extracelulares/metabolismo , Enfermedades del Sistema Nervioso/etiología , Enfermedades del Sistema Nervioso/metabolismo , Hipoxia/metabolismo , Barrera Hematoencefálica/metabolismo , AnimalesRESUMEN
Gliomas represent the most common and lethal category of primary brain tumors. Bisphenol A (BPA), a widely recognized endocrine disruptor, has been implicated in the progression of cancer. Despite its established links to various cancers, the association between BPA and glioma progression remains to be clearly defined. This study aimed to shed light on the impact of BPA on glioma cell proliferation and overall tumor progression. Our results demonstrate that BPA significantly accelerates glioma cell proliferation in a time- and dose-dependent manner. Furthermore, BPA has been found to enhance the invasive and migratory capabilities of glioma cells, potentially promoting epithelial-mesenchymal transition (EMT) characteristics within these tumors. Employing bioinformatics approaches, we devised a risk assessment model to gauge the potential glioma hazards associated with BPA exposure. Our comprehensive analysis revealed that BPA not only facilitates glioma invasion and migration but also inhibits apoptotic processes. In summary, our study offers valuable insights into the mechanisms by which BPA may promote tumorigenesis in gliomas, contributing to the understanding of its broader implications in oncology.
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Glioma , Humanos , Línea Celular Tumoral , Compuestos de Bencidrilo/farmacología , Fenoles/farmacologíaRESUMEN
Introduction: The ratio of Triglyceride (TG) to high-density lipoprotein cholesterol (HDL-C) is a crucial indicator for diabetes diagnosis. Methods: This study utilizes the Copula function to model and fit the non-linear correlation among fasting blood glucose (Glu), glycosylated hemoglobin (HbA1C), and TG/HDL-C in patients with diabetes. The Copula function chosen for this study includes the two-dimensional Archimedes and Elliptical distribution family, as well as the multidimensional Vine Copula function, for fitting the data. The evaluation of the fitting effect is performed using the mean absolute error (MAE) and mean square error (MSE). Results: The results indicate that the Clayton Copula exhibits the highest effectiveness in fitting the pairwise relationship between Glu and TG/HDL-C, as well as HbA1C and TG/HDL-C, displaying the smallest fitting error. Additionally, the Vine Copula function produces a satisfactory fit for the relationship among all three indicators. Compared to linear analysis methods, the Copula function more accurately depicts the correlation among these three types of indicators. Discussion: Moreover, our findings indicate a stronger correlation in the lower tail between Glu and HbA1C, as well as TG/HDL-C, suggesting that the Copula function provides greater accuracy and applicability in depicting the relationship among these indicators. As a result, it can offer a more precise auxiliary diagnosis and serve as a valuable reference in clinical judgment.
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Glucemia , Diabetes Mellitus , Humanos , Hemoglobina Glucada , Diabetes Mellitus/diagnóstico , Triglicéridos , HDL-ColesterolRESUMEN
Most clinically non-functioning pituitary tumour arise from gonadotroph cells. However, clinically functional pituitary gonadotroph adenoma is rare. Here we report a female case who presented with menstrual disturbances, however further workup demonstrated a pituitary microadenoma with elevated FSH and oestradiol level. Transsphenoidal resection was performed and the surgical histopathology confirmed pituitary gonadotroph adenoma. Postoperatively, improvement in both symptoms and hormonal profile were observed. Interestingly, the initially enlarged and polycystic ovaries became within normal range around eight months after the surgery. We suggest functional gonadotroph adenoma should be considered in the presence of gynaecological disorder with persistently elevated oestradiol and FSH levels.