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High temperatures and providing sufficient time for the thermal desorption of persistent organic pollutants (POPs) from contaminated clay soils can lead to intensive energy consumption. Therefore, this article provides a critical review of the potential additives which can improve soil texture and increase the volatility of POPs, and then discusses their enhanced mechanisms for contributing to a green economy. Ca-based additives have been used to reduce plasticity of bentonite clay, absorb water and replenish system heat. In contrast, non-Ca-based additives have been used to decrease the plasticity of kaolin clay. The soil structure and soil plasticity can be changed through cation exchange and flocculation processes. The transition metal oxides and alkali metal oxides can be applied to catalyze and oxidize polycyclic aromatic hydrocarbons, petroleum and emerging contaminants. In this system, reactive oxygen species (â¢O2- and â¢OH) are generated from thermal excitation without strong chemical oxidants. Moreover, multiple active ingredients in recycled solid wastes can be controlled to reduce soil plasticity and enhance thermal catalysis. Alternatively, the alkali, nano zero-valent iron and nano-TiN can catalyze hydrodechlorination of POPs under reductive conditions. Especially, photo and photo-thermal catalysis are discussed to accelerate replacement of fossil fuels by renewable energy in thermal remediation.
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Arcilla , Restauración y Remediación Ambiental , Contaminantes del Suelo , Suelo , Arcilla/química , Suelo/química , Catálisis , Contaminantes del Suelo/química , Restauración y Remediación Ambiental/métodos , CalorRESUMEN
Respiratory tuberculosis (RTB), a global health concern affecting millions of people, has been observationally linked to the gut microbiota, but the depth and nature of this association remain elusive. Despite these findings, the underlying causal relationship is still uncertain. Consequently, we used the Mendelian randomization (MR) method to further investigate this potential causal connection. We sourced data on the gut microbiota from a comprehensive genome-wide association study (GWAS) conducted by the MiBioGen Consortium (7686 cases, and 115,893 controls). For RTB, we procured 2 distinct datasets, labeled the Fingen R9 TBC RESP and Fingen R9 AB1 RESP, from the Finnish Genetic Consortium. To decipher the potential relationship between the gut microbiota and RTB, we employed MR on both datasets. Our primary mode of analysis was the inverse variance weighting (IVW) method. To ensure robustness and mitigate potential confounders, we meticulously evaluated the heterogeneity and potential pleiotropy of the outcomes. In the TBC RESP (RTB1) dataset related to the gut microbiota, the IVW methodology revealed 7 microbial taxa that were significantly associated with RTB. In a parallel vein, the AB1 RESP (RTB2) dataset highlighted 4 microbial taxa with notable links. Notably, Lachnospiraceae UCG010 was consistently identified across both datasets. This correlation was especially evident in the data segments designated Fingen R9 TBC RESP (ORâ =â 1.799, 95% CIâ =â 1.243-2.604) and Finngen R9 AB1 RESP (ORâ =â 2.131, 95% CIâ =â 1.088-4.172). Our study identified a causal relationship between particular gut microbiota and RTB at the level of prediction based on genetics. This discovery sheds new light on the mechanisms of RTB development, which are mediated by the gut microbiota.
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Microbioma Gastrointestinal , Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Microbioma Gastrointestinal/genética , Humanos , Tuberculosis/microbiología , Finlandia/epidemiología , Tuberculosis Pulmonar/microbiología , Tuberculosis Pulmonar/genéticaRESUMEN
This study investigates the storage life of particle-filled polymer composites (PFPCs) under the influence of aging effects. High-temperature accelerated aging tests were conducted at 60 °C, 70 °C, and 80 °C for various days to analyze the impact of aging time and temperature on the mechanical behavior of the materials. A predictive model for crosslink density was established using the Arrhenius equation, and the relationship between crosslink density and relaxation modulus was determined based on polymer physics theory. On this basis, a viscoelastic constitutive model that incorporates aging effects was developed. Structural analyses of a PFPC column with a length of 2.3 m and outer diameter of 1.8 m were performed using the UMAT subroutine in ABAQUS. Subsequently, a safety margin assessment method based on dewetting strain was employed to predict the storage life of the PFPC column. The results indicate that the aging viscoelastic constitutive model effectively characterizes the hardening effects caused by aging in the composites during storage. The storage life for the PFPC column considering aging effects decreases from 22 years to 19 years compared to models that ignore such effects. This approach provides a reference for estimating the storage life of PFPC columns considering aging effects.
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Achieving sufficient attachment of deep rotator cuff tissue to the footprint area on the greater tubercle of the humerus is essential for functional recovery, yet the optimal approach remains uncertain. We introduce a surgical technique for rotator cuff tear repair using a spinal needle to penetrate deep rotator cuff tissue under direct arthroscopic visualization. After trimming the torn edge, an arthroscope is inserted into the joint cavity through a posterior portal, and a hole is drilled into the humeral head cartilage margin using an upper approach, facilitating the implantation of an internal shoulder row nail. A spinal needle is used to introduce a No. 2 polydioxanone (PDS; Johnson & Johnson) line through sufficient deep rotator cuff tissue. Graspers are then used to extract the stitch and PDS together through the anterolateral opening. Once the PDS is knotted, the stitch is introduced into the rotator cuff. This process is replicated to insert additional stitches into the rotator cuff. Our proposed technique, involving a spinal needle under direct visualization, ensures sufficient coverage of the deep rotator cuff tissue over the footprint area and promotes the healing of the repaired rotator cuff. This method is safe, effective, convenient, and reproducible.
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Carbon fiber resin-based composite materials are widely employed in the manufacturing of composite shells. During the curing process, the temperature gradients and cure degree gradients make it easy to generate thermal strains in both carbon fibers and resin, with the resin experiencing cure shrinkage strain due to the curing reaction, ultimately leading to residual stresses and strains. In this paper, a three-dimensional thermo-chemo-mechanical coupled curing model of the composite shell was established based on a resin test, and the changes of temperature, curing degree, residual stress, and strain during the solidification of the composite shell were investigated. First, the curing property parameters and elastic modulus of HCM-2184 resin were obtained through a curing dynamic test and a tensile test. Then, considering the heat release and shrinkage reaction of solidification, a coupled thermo-chemo-mechanical curing model was developed with the CHILE (α) elastic model, and the curing process of the composite shell was simulated numerically. The results show that the resin used in the test belongs to the autocatalytic reaction. For thin composite shells, the heat accumulation inside the shell during curing is not obvious. During the curing process, the curing shrinkage behavior of the resin is an important factor for the generation of residual stress and residual strain.
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Burn injuries, especially severe ones, result in direct and indirect thermal damage to skin tissues, with a complex and slow wound healing process. Improper treatment can induce sustained inflammatory responses, causing systemic damage. Lin28A, a highly conserved RNA binding protein, was found to exert a significant effect on cell proliferation and wound repair. Lin28A exerts the functions through inhibiting the maturation of the let-7 family miRNAs. Herein, the roles of Lin28A and let-7b in thermal injury repair were investigated using a mouse thermal injury model and a human skin fibroblast (HSF) model for thermal injuries. Lin28A could inhibit the maturation of let-7b, thus participating in skin repair after burns. In the animal model, Lin28A was highly expressed after thermal injury. In the HSF model for thermal injuries, downregulation of Lin28A inhibited the proliferation, migration, and extracellular matrix (ECM) generation of fibroblasts. When let-7b was knocked down in HSFs, the impacts on fibroblast functions caused by downregulation of Lin28A were partially reversed. Moreover, let-7b overexpression might significantly attenuate the promotive effects of Lin28A upon thermal injury repair. Finally, AKT2 and IGF1R were the let-7b target genes within cells. These findings reveal that Lin28A might promote thermal injury repair in burn-injured skin by inhibiting the maturation of let-7b and improving HSF viability and functions, thus illustrating the critical effect of let-7b on burn wound healing and providing new therapeutic targets and strategies for burn treatment.
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Quemaduras , Proliferación Celular , Fibroblastos , MicroARNs , Proteínas de Unión al ARN , Piel , Cicatrización de Heridas , Quemaduras/patología , Quemaduras/metabolismo , Quemaduras/genética , Animales , MicroARNs/metabolismo , MicroARNs/genética , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética , Humanos , Ratones , Fibroblastos/metabolismo , Piel/patología , Piel/metabolismo , Piel/lesiones , Masculino , Movimiento Celular , Ratones Endogámicos C57BL , Modelos Animales de EnfermedadRESUMEN
Objective: To explore the therapeutic effect of basic fibroblast growth factor (bFGF) on spinal cord injury (SCI) in rats and the influence of Notch/signal transducer and activator of transcription 3 (STAT3) signaling pathway. Methods: A total of 40 10-week-old male Sprague Dawley (SD) rats were selected to establish T 10-segment SCI model by a free falling object. Among them, 32 successful models were randomly divided into model group and bFGF group, with 16 in each group. Another 16 SD rats were selected as sham-operation group, with only T 10 processes, dura mater, and spinal cord exposed. After modeling, the rats in bFGF group were intraperitoneally injected with 100 µg/kg bFGF (once a day for 28 days), and the rats in model group and sham-operation group were injected with normal saline in the same way. The survival of rats in each group were observed after modeling. Basso-Beattie-Bresnahan (BBB) scores were performed before modeling and at immediate, 14 days, and 28 days after modeling to evaluate the functional recovery of hind limbs. Then, the spinal cord tissue at the site of injury was taken at 28 days and stained with HE, Nissl, and propidium iodide (PI) to observe the pathological changes, neuronal survival (number of Nissl bodies) and apoptosis (number of PI red stained cells) of the spinal cord tissue; immunohistochemical staining and ELISA were used to detect the levels of astrocyte activation markers [glial fibrillary acidic protein (GFAP)] and inflammatory factors [interleukin 1ß (IL-1ß), tumor necrosis factor α (TNF-α), interferon γ (IFN-γ)] in tissues, respectively. Western blot was used to detect the expressions of Notch/STAT3 signaling pathway related proteins [Notch, STAT3, phosphoryl-STAT3 (p-STAT3), bone morphogenetic protein 2 (BMP-2)] in tissues. Results: All rats survived until the experiment was completed. At immediate after modeling, the BBB scores in model group and bFGF group significantly decreased when compared to sham-operation group ( P<0.05). At 14 and 28 days after modeling, the BBB scores in model group significantly decreased when compared to sham-operation group ( P<0.05); the bFGF group showed an increase compared to model group ( P<0.05). Compared with before modeling, the BBB scores of model group and bFGF group decreased at immediate after modeling, and gradually increased at 14 and 28 days, the differences between different time points were significant ( P<0.05). The structure of spinal cord tissue in sham-operation group was normal; in model group, there were more necrotic lesions in the spinal cord tissue and fewer Nissl bodies with normal structures; the number of necrotic lesions in the spinal cord tissue of the bFGF group significantly reduced compared to the model group, and some normally structured Nissl bodies were visible. Compared with sham-operation group, the number of Nissl bodies in spinal cord tissue significantly decreased, the number of PI red stained cells, GFAP, IL-1ß, TNF-α, IFN-γ, Notch, p-STAT3 /STAT3, BMP-2 protein expression levels significantly increased in model group ( P<0.05). The above indexes in bFGF group significantly improved when compared with model group ( P<0.05). Conclusion: bFGF can improve motor function and pathological injury repair of spinal cord tissue in SCI rats, improve neuronal survival, and inhibit neuronal apoptosis, excessive activation of astrocytes in spinal cord tissue and inflammatory response, the mechanism of which may be related to the decreased activity of Notch/STAT3 signaling pathway.
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Factor 2 de Crecimiento de Fibroblastos , Traumatismos de la Médula Espinal , Ratas , Masculino , Animales , Ratas Sprague-Dawley , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Factor de Transcripción STAT3/metabolismo , Factor de Transcripción STAT3/farmacología , Factor de Transcripción STAT3/uso terapéutico , Factor de Necrosis Tumoral alfa/metabolismo , Traumatismos de la Médula Espinal/terapia , Médula Espinal/metabolismo , Transducción de SeñalRESUMEN
Fresh lotus seeds are gaining favor with consumers for their crunchy texture and natural sweetness. However, the intricacies of sugar accumulation in lotus seeds remain elusive, which greatly hinders the quality improvement of fresh lotus seeds. This study endeavors to elucidate this mechanism by identifying and characterizing the sucrose synthase (SUS) gene family in lotus. Comprising five distinct members, namely NnSUS1 to NnSUS5, each gene within this family features a C-terminal glycosyl transferase1 (GT1) domain. Among them, NnSUS1 is the predominately expressed gene, showing high transcript abundance in the floral organs and cotyledons. NnSUS1 was continuously up-regulated from 6 to 18 days after pollination (DAP) in lotus cotyledons. Furthermore, NnSUS1 demonstrates co-expression relationships with numerous genes involved in starch and sucrose metabolism. To investigate the function of NnSUS1, a transient overexpression system was established in lotus cotyledons, which confirmed the gene's contribution to sugar accumulation. Specifically, transient overexpression of NnSUS1 in seed cotyledons leads to a significant increase in the levels of total soluble sugar, including sucrose and fructose. These findings provide valuable theoretical insights for improving sugar content in lotus seeds through molecular breeding methods.
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Cotiledón , Glucosiltransferasas , Lotus , Proteínas de Plantas , Cotiledón/genética , Cotiledón/metabolismo , Cotiledón/enzimología , Regulación de la Expresión Génica de las Plantas , Glucosiltransferasas/metabolismo , Glucosiltransferasas/genética , Lotus/genética , Lotus/enzimología , Lotus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Semillas/genética , Semillas/metabolismo , Semillas/enzimología , Sacarosa/metabolismo , Azúcares/metabolismoRESUMEN
Ferroptosis inhibits tumor growth by iron-dependently accumulating lipid peroxides (LPO) to a lethal extent, which can result from iron overload and glutathione peroxidase 4 (GPX4) inactivation. In this study, we developed biodegradable zwitterionic polymer-cloaked atorvastatin (ATV)-loaded ferric metal-organic frameworks (Fe-MOFs) for cancer treatment. Fe-MOFs served as nanoplatforms to co-deliver ferrous ions and ATV to cancer cells; the zwitterionic polymer membrane extended the circulation time of the nanoparticles and increased their accumulation at tumor sites. In cancer cells, the structure of the Fe-MOFs collapsed in the presence of glutathione (GSH), leading to the depletion of GSH and the release of ATV and Fe2+. The released ATV decreased mevalonate biosynthesis and GSH, resulting in GPX4 attenuation. A large number of reactive oxygen species were generated by the Fe2+-triggered Fenton reaction. This synergistic effect ultimately contributed to a lethal accumulation of LPO, causing cancer cell death. The findings both in vitro and in vivo suggested that this ferroptosis-inducing nanoplatform exhibited enhanced anticancer efficacy and preferable biocompatibility, which could provide a feasible strategy for anticancer therapy.
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Ferroptosis , Estructuras Metalorgánicas , Neoplasias , Humanos , Polímeros , Atorvastatina , Glutatión , Hierro , Peróxidos Lipídicos , Neoplasias/tratamiento farmacológico , Línea Celular TumoralRESUMEN
Riverine nitrogen pollution is ubiquitous and attracts considerable global attention. Nitrate is commonly the dominant total nitrogen (TN) constituent in surface and ground waters; thus, stable isotopes of nitrate (δ15N/δ18O-NO3-) are widely used to differentiate nitrate sources. However, δ15N/δ18O-NO3- approach fails to present a holistic perspective of nitrogen pollution for many coastal-plain river networks because diverse nitrogen species contribute to high TN loads. In this study, multiple isotopes, namely, δ15N/δ18O-NO3-, δ18O-H2O, δ15N-NH4+, δ15N-PN, and δ15Nbulk/δ18O/SP-N2O in the Wen-Rui Tang River, a typical coastal-plain river network of Eastern China, were investigated to identify transformation processes and sources of nitrogen. Then, a stable isotope analysis in R (SIAR) model-TN source apportionment method was developed to quantify the contributions of different nitrogen sources to riverine TN loads. Results showed that nitrogen pollution in the river network was serious with TN concentrations ranging from 1.71 to 8.09 mg/L (mean ± SD: 3.77 ± 1.39 mg/L). Ammonium, nitrate, and suspended particulate nitrogen were the most prominent nitrogen components during the study period, constituting 45.4 %, 28.9 %, and 19.9 % of TN, respectively. Multiple hydrochemical and isotopic analysis identified nitrification as the dominant N cycling process. Biological assimilation and denitrification were minor N cycling processes, whereas ammonia volatilization was deemed negligible. Isotopic evidence and SIAR modeling revealed municipal sewage was the dominant contributor to nitrogen pollution. Based on quantitative estimates from the SIAR model, nitrogen source contributions to the Wen-Rui Tang River watershed followed: municipal sewage (40.6 %) ≈ soil nitrogen (39.5 %) > nitrogen fertilizer (9.7 %) > atmospheric deposition (2.8 %) during wet season; and municipal sewage (59.1 %) > soil nitrogen (30.4 %) > nitrogen fertilizer (4.1 %) > atmospheric deposition (1.0 %) during dry season. This study provides a deeper understanding of nitrogen dynamics in eutrophic coastal-plain river networks, which informs strategies for efficient control and remediation of riverine nitrogen pollution.
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Dual nitrate isotopes (δ15N/δ18O-NO3-) are an effective tool for tracing nitrate sources in freshwater systems worldwide. However, the initial δ15N/δ18O values of different nitrate sources might be altered by isotopic fractionation during nitrification, thereby limiting the efficiency of source apportionment results. This study integrated hydrochemical parameters, site-specific isotopic compositions of potential nitrate sources, multiple stable isotopes (δD/δ18O-H2O, δ15N/δ18O-NO3- and Δ17O-NO3-), soil incubation experiments assessing the nitrification 15N-enrichment factor (εN), and a Bayesian mixing model (MixSIAR) to reduce/eliminate the influence of 15N/18O-fractionations on nitrate source apportionment. Surface water samples from a typical drinking water source region were collected quarterly (June 2021 to March 2022). Nitrate concentrations ranged from 0.35 to 3.06 mg/L (mean = 0.78 ± 0.46 mg/L), constituting â¼70 % of total nitrogen. A MixSIAR model was developed based on δ15N/δ18O-NO3- values of surface waters and the incorporation of a nitrification εN (-6.9 ± 1.8 ). Model source apportionment followed: manure/sewage (46.2 ± 10.7 %) > soil organic nitrogen (32.3 ± 18.5 %) > nitrogen fertilizer (19.7 ± 13.1 %) > atmospheric deposition (1.8 ± 1.6 %). An additional MixSIAR model coupling δ15N/δ18O-NO3- with Δ17O-NO3- and εN was constructed to estimate the potential nitrate source contributions for the June 2021 water samples. Results revealed similar nitrate source contributions (manure/sewage = 43.4 ± 14.1 %, soil organic nitrogen = 29.3 ± 19.4 %, nitrogen fertilizer = 19.8 ± 13.8 %, atmospheric deposition = 7.5 ± 1.6 %) to the original MixSIAR model based on εN and δ15N/δ18O-NO3-. Finally, an uncertainty analysis indicated the MixSIAR model coupling δ15N/δ18O-NO3- with Δ17O-NO3- and εN performed better as it generated lower uncertainties with uncertainty index (UI90) of 0.435 compared with the MixSIAR model based on δ15N/δ18O-NO3- (UI90 = 0.522) and the MixSIAR model based on δ15N/δ18O-NO3- and εN (UI90 = 0.442).
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The transition to flowering is a vital process in the lotus life cycle that significantly impacts its ornamental value and seed production. However, the molecular basis of floral transition in lotus remains largely unknown. Here, eight homologous FLOWERING LOCUS T (FT) genes were initially characterized in lotus, which were designated as NnFT1-NnFT8. All of these genes were found to possess the conserved PEBP domain and exhibited high transcript levels in both lotus leaves and floral organs. The proNnFT:ß-glucuronidase (GUS) assay exhibited GUS staining in the vascular tissues of leaves. Furthermore, subcellular localization revealed that NnFT proteins were present in various cellular organelles, including the nucleus, cytoplasm, and endoplasmic reticulum. Overexpression of two NnFT homologs, NnFT2 and NnFT3, rescued the late flowering phenotype in the Arabidopsis ft-10 mutant, indicating the stimulative roles of NnFTs in floral induction. Moreover, NnFTs demonstrated interactions with a bZIP transcription factor, FLOWERING LOCUS D (NnFD), both in vitro and in vivo. These findings will not only deepen our understanding of the regulatory mechanism underlying lotus floral transition, but also provide valuable genetic resources for creating new lotus varieties with extended blooming periods using molecular strategies in the future.
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Proteínas de Arabidopsis , Arabidopsis , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Flores/genética , Flores/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Hojas de la Planta/metabolismo , Regulación de la Expresión Génica de las PlantasRESUMEN
The ubiquitous occurrence of micro/nano plastics (MNPs) poses potential threats to ecosystem and human health that have attracted broad concerns in recent decades. Detection of MNPs in several remote regions has implicated atmospheric transport as an important pathway for global dissemination of MNPs and hence as a global health risk. In this review, the latest research progress on (1) sampling and detection; (2) origin and characteristics; and (3) transport and fate of atmospheric MNPs was summarized. Further, the current status of exposure risks and toxicological effects from inhaled atmospheric MNPs on human health is examined. Due to limitations in sampling and identification methodologies, the study of atmospheric nanoplastics is very limited today. The large spatial variation of atmospheric MNP concentrations reported worldwide makes it difficult to compare the overall indoor and outdoor exposure risks. Several in vitro, in vivo, and epidemiological studies demonstrate adverse effects of immune response, apoptosis and oxidative stress caused by MNP inhalation that may induce cardiovascular diseases and reproductive and developmental abnormalities. Given the emerging importance of atmospheric MNPs, the establishment of standardized sampling-pretreatment-detection protocols and comprehensive toxicological studies are critical to advance environmental and health risk assessments of atmospheric MNPs.
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Enfermedades Cardiovasculares , Ecosistema , Humanos , Microplásticos , Atmósfera , Apoptosis , PlásticosRESUMEN
Anterior cruciate ligament (ACL) rupture often presents with a tear of the posterior horn of the lateral meniscus. There is no clear preference between ACL reconstruction with suture and resection of the meniscus. We aimed to compare the clinical efficacy of ACL reconstruction with suture versus resection in patients presenting with arthroscopic ACL rupture and radial complete tear of the posterior corner of the lateral meniscus. We retrospectively analyzed 157 patients with ACL rupture and complete radial tear of the posterior horn of the lateral meniscus. Between May 2010 and April 2015, 86 of 157 patients underwent ACL reconstruction and meniscus suture (study group, 54.78%) and 71 of 157 patients underwent ACL reconstruction and meniscus resection (control group, 45.22%) in our department. All patients were monitored over the 12 to 72-month follow-up period. The primary evaluation indices were the Lysholm scores, the International Knee Documentation Committee (IKDC) scores, pivot shift test, the Barret criteria, and magnetic resonance imaging (MRI) findings of meniscal healing. The majority of 157 patients were relatively young men (29.64 ± 7.79 years) with low body mass index (BMI) (23.79 ± 2.74). The postoperative Lysholm and IKDC scores of the two groups were significantly improved over the corresponding preoperative scores (p < 0.05). The clinical results and excellent and good rates were significantly better for the study group than for the control group (both, p < 0.05). MRI showed that the meniscal healed rate of the study group was 96.51%. There was no significant difference in BMI between subgroups for any functional outcome. For patients with ACL rupture and complete radial tear of the posterior horn of the lateral meniscus, ACL reconstruction and both simultaneous suture and resection of the posterior horn of the lateral meniscus were found to be safe and effective. There was no association between outcomes and BMI. However, the former was associated with a superior long-term clinical effect and may restore the integrity of the meniscus and is particularly recommended for young patients.
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Lesiones del Ligamento Cruzado Anterior , Ligamento Cruzado Anterior , Masculino , Humanos , Ligamento Cruzado Anterior/cirugía , Meniscos Tibiales/diagnóstico por imagen , Meniscos Tibiales/cirugía , Estudios Retrospectivos , Lesiones del Ligamento Cruzado Anterior/cirugía , Rotura/cirugía , SuturasRESUMEN
The concentration of airborne microplastics is largely unknown in the remote high mountain area of the Tibetan Plateau. Here we report airborne microplastic concentrations of 2.5-58.8 n/m3 in urban, rural and wildland areas across the Tibetan Plateau, with smaller (â¼89% <100 µm) fragments (>80%) dominating. Polyethylene terephthalate, polyethylene, polyamide and polystyrene were the dominant polymers of airborne microplastics on the Tibetan Plateau. Distribution of airborne microplastics was positively correlated with anthropogenic activity indices, such as population density and nighttime light intensity. Although the contribution of long-range atmospheric transport is valid, dispersed villages also appear to be a source of airborne microplastics for wildland areas across the Tibetan Plateau.
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In this study, the aging performance of particle-filled polymer composites (PFPCs) under thermo-oxidative conditions was investigated on multiple scales. High-temperature-accelerated tests were conducted to analyze the effects of aging time and temperature. A representative volume element (RVE) model was established for the PFPCs using a random particle-filling algorithm. A predictive model for the crosslink density was conducted based on the closed-loop chain reaction of polymer oxidation. According to the theory of polymer physics, the relation between the crosslink density and matrix modulus was determined. The particle/matrix interface in the RVE model was represented by the cohesive zone model (CZM). The parameters of the CZM were determined by the inversion techniques. Then, a comprehensive multiscale RVE model was constructed, which was applied to predict the modulus and dewetting strain of the aged PFPCs. The predicted results show good agreement with the test results, which verifies the reliability of our model.
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This study aimed to explore the risk factors for infection and bleeding after lateral decubitus percutaneous nephrolithotomy procedures to prevent their occurrence and improve surgical outcomes. A retrospective analysis was conducted on 356 patients who underwent lateral decubitus percutaneous nephrolithotomy for the treatment of kidney stones and upper ureteral stones from January 2015 to August 2022. Among them, 290 patients had complete clinical data. General clinical data, perioperative data, and stone characteristics were collected for each patient. Univariate and multivariate logistic regression analyses were performed to identify risk factors for infection and bleeding after lateral decubitus percutaneous nephrolithotomy. The postoperative infection rate after lateral decubitus percutaneous nephrolithotomy was 19.31%, and the postoperative bleeding rate was 12.07%. Independent risk factors for postoperative infection were multiple stones (P < .001), stone size (P < .001), and stone co-infection (P = .012). Independent risk factors for postoperative bleeding were multiple stones (P = .008) and stone size (P = .014). Multiple stones, stone size, and stone co-infection are independent risk factors for postoperative infection after lateral decubitus percutaneous nephrolithotomy. Multiple stones and stone size are independent risk factors for postoperative bleeding after lateral decubitus percutaneous nephrolithotomy.
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Coinfección , Cálculos Renales , Nefrolitotomía Percutánea , Nefrostomía Percutánea , Cálculos Ureterales , Humanos , Nefrolitotomía Percutánea/efectos adversos , Nefrolitotomía Percutánea/métodos , Estudios Retrospectivos , Coinfección/etiología , Cálculos Renales/cirugía , Factores de Riesgo , Hemorragia Posoperatoria/epidemiología , Hemorragia Posoperatoria/etiología , Cálculos Ureterales/etiología , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Resultado del Tratamiento , Nefrostomía Percutánea/efectos adversos , Nefrostomía Percutánea/métodosRESUMEN
Callus browning is a major drawback to lotus callus proliferation and regeneration. However, the underlying mechanism of its formation remains largely unknown. Herein, we aimed to explore the metabolic and molecular basis of lotus callus browning by combining histological staining, high-throughput metabolomics, and transcriptomic assays for lotus callus at three browning stages. Histological stained brown callus cross sections displayed severe cell death symptoms, accompanied by an obvious accumulation of polyphenols and lignified materials. Widely targeted metabolomics revealed extensively decreased accumulation of most detected flavonoids and benzylisoquinoline alkaloids (BIAs), as well as a few phenolic acids, amino acids and their derivatives in callus with browning symptoms. Conversely, the contents of most detected tannins were significantly increased. Subsequent comparative transcriptomics identified a set of differentially expressed genes (DEGs) associated with the biosynthesis and regulation of flavonoids and BIAs in lotus. Notably, callus browning was coupled with significantly up-regulated expression of two polyphenol oxidase (PPO) and 17 peroxidase (POD) encoding genes, while the expression of ethylene associated genes remained at marginal levels. These results suggest that lotus callus browning is primarily controlled at the level of metabolism, wherein the oxidation of flavonoids and BIAs is crucially decisive.
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Lotus , Nelumbo , Nelumbo/genética , Nelumbo/metabolismo , Lotus/metabolismo , Transcriptoma/genética , Perfilación de la Expresión Génica , Flavonoides/metabolismoRESUMEN
In this study, we developed a novel multi-scale model to predict the aging performance of particle-filled polymer composites (PFPCs) under thermo-oxidative aging conditions. To investigate the aging behavior, high-temperature accelerated aging tests were conducted in combination with macroscopic and microscopic characterization. At the microscopic level, the crosslinking density of the polymer matrix is calculated using the closed-loop chain reaction of polymer oxidation. In addition, the theory of polymer physics was used to determine the relationship between crosslinking density and elastic modulus. Relationships between elastic modulus and dewetting strain were analyzed at the macroscopic level. Based on the observations and analyses, a multi-scale model was developed to predict the aging performance of PFPCs. The predicted results show good agreement with the test results, which verifies the reliability of the model.
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In hyperspectral image (HSI) classification, convolutional neural networks (CNNs) have been widely employed and achieved promising performance. However, CNN-based methods face difficulties in achieving both accurate and efficient HSI classification due to their limited receptive fields and deep architectures. To alleviate these limitations, we propose an effective HSI classification network based on multi-head self-attention and spectral-coordinate attention (MSSCA). Specifically, we first reduce the redundant spectral information of HSI by using a point-wise convolution network (PCN) to enhance discriminability and robustness of the network. Then, we capture long-range dependencies among HSI pixels by introducing a modified multi-head self-attention (M-MHSA) model, which applies a down-sampling operation to alleviate the computing burden caused by the dot-product operation of MHSA. Furthermore, to enhance the performance of the proposed method, we introduce a lightweight spectral-coordinate attention fusion module. This module combines spectral attention (SA) and coordinate attention (CA) to enable the network to better weight the importance of useful bands and more accurately localize target objects. Importantly, our method achieves these improvements without increasing the complexity or computational cost of the network. To demonstrate the effectiveness of our proposed method, experiments were conducted on three classic HSI datasets: Indian Pines (IP), Pavia University (PU), and Salinas. The results show that our proposed method is highly competitive in terms of both efficiency and accuracy when compared to existing methods.