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Materials with lower dielectric loss and greater thermal and mechanical properties have drawn public attention with the rapid development of 5G technology. However, the mastery and understanding of the aging mechanism and working lifetime of these specific materials remain an open challenge. Here, we designed a glass fiber (GF)-reinforced acrylate–styrene–acrylonitrile/polycarbonate (ASA/GF/PC) composite and systematically investigated its aging behavior, aging mechanism, and lifetime prediction under long-term thermal and oxidative conditions. The aging behaviors regarding the mechanical, dielectric properties and color change were deeply analyzed at four aging temperatures. Results indicated that impact strength was applicable to estimate working lifetime. Assisted by general Arrhenius kinetic models, the predicted lifetimes were 22,334 days at 303 K, 8605 days at 313 K, 3517 days at 323 K, and 1516 days at 333 K, respectively. The study of aging mechanism confirmed that thermal degradation inevitably occurred in the ASA and PC phases, which provoked the appearance of newborn oxygen-containing groups and further induced the generation of cross-linked domains. The desired results provide a valuable reference to guide the widespread and long-term utilization of ASA/GF/PC composites in 5G technology. [ABSTRACT FROM AUTHOR]

The development of fifth‐generation technology has resulted in increased demand for materials with low dielectric losses and superior thermal and mechanical properties. However, ensuring the widespread use of such materials by investigating their aging mechanisms and operating lifetimes remains challenging. In this study, a glass‐fiber (GF)‐reinforced acrylate‐styrene‐acrylonitrile/polycarbonate (ASA/GF/PC) composite is designed and comprehensively investigated its aging behavior, mechanism, and service lifetime under long‐term hygrothermal conditions. Based on the general Peck model, the composite maintains a high level of quality for over 10 years, including under harsh conditions of 40 °C and 80% relative humidity. The aging mechanism is primarily ascribed to cracking between the GF fibers and matrix, the breaking of chemical bonds, the generation of new cross‐linked domains, and physical aging. These findings provide valuable insights into the long‐term utilization of ASA/GF/PC composites in harsh environments. [ABSTRACT FROM AUTHOR]

The successful implementation of the low-carbonization strategy is heavily reliant on the development of low-loss and high-efficiency green antenna technology. However, long-term exposure to high heat and oxygen leads to the degradation of antenna materials and the release of harmful substances. Studies on the aging behavior and mechanism of the antenna materials are of essence to realize the low-carbonization strategy. To address this issue, an unplasticized polyvinyl chloride filled with calcium carbonate (uPVC/CaCO 3) has been successfully prepared using the injection molding technique. After that, the aging behavior, mechanism, and working lifetime were comprehensively explored under thermal and oxidative conditions. It is found that the composite maintains a high level of functionality for up to 24 years at 60 ℃ and 4.5 years at 70 ℃ on the impact strength failure criterion. The simultaneous oxidation and dehydrochlorination reaction, cross-linking reaction, and deterioration of the interaction between components are responsible for the aging of the uPVC/CaCO 3 composite. These findings provide valuable insights into the development of radome materials for achieving low-loss and high-efficiency green antenna technology. [ABSTRACT FROM AUTHOR]

This study investigated the clinical characteristics of Hodgkin lymphoma-associated hemophagocytic lymphohistiocytosis (HLH-HL). Clinical data of 8 patients with HLH-HL and 20 non-HLH-HL patients were included. All eight HLH-HL patients tested positive for plasma Epstein-Barr virus (EBV)-DNA and EBV-encoded small RNA (EBER), and six patients were positive for EBV-DNA in the peripheral blood mononuclear cells (PBMCs). Two out of the 20 non-HLH-HL patients were confirmed positive for EBER, and the remaining 18 patients were negative. Among the HLH-HL patients, five patients received ABVD (doxorubicin/bleomycin/vinblastine/dacarbazine) chemotherapy regimens in other hospitals, and their conditions were considered to be worse, for which reason they were transferred to our center, and three patients were treated with DEP (doxorubicin-etoposide-methylprednisolone) regimens to target HLH and were alive as of the writing of this article. Two patients were critically ill upon admission and were not able to undergo chemotherapy. Significant differences in survival time were observed between the HLH-HL and non-HLH-HL patients (P = 0.005). HL patients found positive for EBV (plasma/PBMCs EBV-DNA(+)/EBER(+)) may be more likely to develop HLH-HL. It may be beneficial to target HLH during the acute phase of HLH, followed by treating HL once the HLH condition has stabilized. HLH-HL patients have worse prognosis and higher mortality than non-HLH-HL patients. [ABSTRACT FROM AUTHOR]

Currently, the integration of satellite-based LiDAR (ICESat-2) and continuous remote sensing imagery has been extensively applied to mapping forest canopy height over large areas. A considerable fraction of low-quality photons exists in ICESAT-2/ATL08 products, which restricts the performance of regional canopy height estimation. To solve these problems, a Local Noise Removal-Light Gradient Boosting Machine (LNR-LGB) method was proposed in this study, which efficiently filtered the unreliable canopy photons in ATL08, constructed an extrapolation model by combining multiple remote sensing data, and finally mapped the 30 m forest canopy height of Hunan Province in 2020. To verify the feasibility of this method, the canopy parameters were also filtered based on ATL08 product attributes (traditional method), and the accuracy of the two models was compared using the 10-fold cross-validation. The conclusions were as follows: (1) compared with the traditional model, the overall accuracy of the LNR-LGB model was approximately doubled, in which R2 increased from 0.46 to 0.65 and RMSE decreased from 6.11 m to 3.48 m; (2) the forest height in Hunan Province ranged from 2.53 to 50.79 m with an average value of 18.34 m. The LNR-LGB method will provide a new concept for achieving high-accuracy mapping of regional forest height. [ABSTRACT FROM AUTHOR]

Investigation of the family showed that: compound heterozygous mutations were found in the I UNC13D i gene, specifically a heterozygous missense mutation c.407G > A and heterozygous nonsense mutation c.640C > T. These two mutation sites were found to have derived from both parents (Fig. 1 Family diagram and gene sequencing of patient A, mutations of A were found in the UNC13D gene (a heterozygous missense mutation c.407G>A and a heterozygous nonsense mutation c.640C>T). Family diagram and gene sequencing of patient C, mutations of C were found in the PRF1 gene (heterozygous missense mutations c.46C>T and c.1066C>T). [Extracted from the article]

Objective: A major cause of hemophagocytic lymphohistiocytosis (HLH) is malignant neoplasms of the blood system, among which NK/T cell lymphoma is one of the most common risk factors. Patients with NK/T cell lymphoma hemophagocytic lymphohistiocytosis (NK/T-LAHS) have a worse prognosis and higher mortality. We aimed to explore the factors that affect the prognosis of NK/T-LAHS. Methods: Clinical data of 42 patients with NK/T-LAHS diagnosed by Beijing Friendship Hospital from June 2008 to June 2016 were analyzed retrospectively. The survival time was counted until 1 August 2016. Results: For the 42 NK/T-LAHS patients, 1-month survival rate was 48.9%, 2-month survival rate was 36.7%, 3-month survival rate was 28.8%, 6-month survival rate was 23.0%, and 12-month survival rate was 15.4%. NK/T-LAHS patients who underwent allogeneic hematopoietic stem cell transplantation (Allo-HSCT) (p = 0.000), exhibited peripheral blood Epstein-Barr virus (EBV)-positivity (p = 0.004), and achieved overall response (OR) remission after initial induction therapy (p = 0.007) had statistical significance. Conclusion: NK/T-LAHS is a disease of poor prognosis and high mortality. NK/T-LAHS patients who achieved OR remission after the initial induction therapy had a better prognosis than non-remission patients and Allo-HSCT was an effective way to prolong the survival of NK/T-LAHS patients. However, EBV positivity in peripheral blood was a poor prognostic factor in NK/T-LAHS patients. [ABSTRACT FROM AUTHOR]

Background: This study investigated the clinical characteristics of primary hemophagocytic lymphohistiocytosis (HLH) in adults, including immunological markers, pedigree findings, and conditions of allogeneic hematopoietic stem cell transplantation (Allo-HSCT).Methods: The study included clinical data of 18 adult patients with primary HLH treated in our center from June 2010 to January 2017.Results: Of these 18 cases, pathogenic variants were found in the following genes: PRF1 (n = 11), UNC13D (n = 5), SH2D1A (n = 2), RAB27a (n = 1), and LYST (n = 2). One patient had pathogenic variants in both PRF1 and UNC13D genes, one patient had pathogenic variants in both LYST and UNC13D genes and another patient had pathogenic variants in both PRF1 and SH2D1A genes. Additionally, 3 of the 18 cases involved homozygous pathogenic variants, while 2 cases involved hemizygous pathogenic variants. The remaining 13 cases involved compound heterozygous pathogenic variants. The natural killer (NK) cell activity test was conducted in all 18 cases where 14(77.8%)patients showed reduction in NK cell activity. Furthermore, this article presents 3 representative results of the pedigree findings from 12 patients who underwent family surveys. The 8 patients who underwent Allo-HSCT had a median survival of 27.2 months, as compared with the median survival of 7 months for the10 patients who did not undergo Allo-HSCT, a significant difference between the two groups of patients (p = 0.006).Conclusion: PRF1 was one of the most commonly mutated gene in adult patients with primary HLH. Family surveys and immunological markers were important for the HLH diagnosis and the selection of an appropriate donor. Allo-HSCT was an effective therapy for adult primary HLH. [ABSTRACT FROM AUTHOR]

High concentrations of fine particulate matter (PM2.5) are well known to reduce environmental quality, visibility, atmospheric radiation, and damage the human respiratory system. Satellite-based aerosol retrievals are widely used to estimate surface PM2.5 levels because satellite remote sensing can break through the spatial limitations caused by sparse observation stations. In this work, a spatiotemporal weighted bagged-tree remote sensing (STBT) model that simultaneously considers the effects of aerosol optical depth, meteorological parameters, and topographic factors was proposed to map PM2.5 concentrations across China that occurred in 2018. The proposed model shows superior performance with the determination coefficient (R2) of 0.84, mean-absolute error (MAE) of 8.77 μg/m3 and root-mean-squared error (RMSE) of 15.14 μg/m3 when compared with the traditional multiple linear regression (R2 = 0.38, MAE = 18.15 μg/m3, RMSE = 29.06 μg/m3) and linear mixed-effect (R2 = 0.52, MAE = 15.43 μg/m3, RMSE = 25.41 μg/m3) models by the 10-fold cross-validation method. The results collectively demonstrate the superiority of the STBT model to other models for PM2.5 concentration monitoring. Thus, this method may provide important data support for atmospheric environmental monitoring and epidemiological research. [ABSTRACT FROM AUTHOR]

The top of the boundary layer, referred to as the planetary boundary layer height (BLH), is an important physical parameter in atmospheric numerical models, which has a critical role in atmospheric simulation, air pollution prevention, and climate prediction. The traditional methods for determining BLHs using Doppler lidar vertical velocity variance ( σ w 2 ) can be classified into the variance and peak methods, which depend on atmospheric conditions due to their use of a single threshold, hence limiting their ability to estimate diurnal BLHs. Edge detection (ED) was later introduced in BLH estimation due to its ability to identify the 2D gradient of an image. A key step in ED is automatically identifying the edge of BLHs based on the peaks of the profile, hence avoiding the influence of extreme atmospheric conditions. Two cases in the diurnal cycle on 4 March 2019 and 8 July 2019 reveal that ED outperforms both the variance and peak methods in nighttime and extreme atmospheric conditions. The retrieved BLHs from 2018 to 2020 were compared with radiosonde (RS) measurements for the same time at the neutral, stable, and convective boundary layers. The correlation coefficient (R: 0.4 vs. 0.05, 0.14; 0.26 vs. −0.10, −0.16; 0.35 vs. 0.01, 0.16) and root mean square error (RMSE (km): 0.58 vs. 0.82, 0.90; 0.37 vs. 1.01, 0.50; 0.66 vs. 0.98, 0.82) obtained by the ED method were higher and lower than those obtained by the variance and peak methods, respectively. The mean absolute error (MAE) of the ED method under the NBL, SBL, and CBL conditions are lower than the variance and peak methods (MAE (km): 0.44, 0.14, 0.50 vs. 0.62, 0.34, 0.64; 0.59, 0.75, 0.74), respectively. The mean relative error (MRE) of the ED method is lower than the variance and peak methods under the NBL condition (MRE: −8.88% vs. −18.39%, 13.91%). Under the SBL, the MRE of the ED method is lower than the variance method and higher than the peak method (−38.64%, vs. −152.23%; 14.02%). Under the CBL, the MRE of the ED method is lower than the variance method and higher than the peak method (−15.07% vs. 2.24%; 5.64%). In addition, the comparison between ED and wavelet covariance transform (WCT) method and RS measurements showed that the ED method has a similar performance with the WCT method and is even better. In the long-term analysis, the hourly and monthly BLHs in the diurnal and annual cycles, respectively, as obtained by ED, were highly consistent with the RS measurements and obtained the lowest standard error. In the annual cycle, the retrieved BLHs in summer and autumn were higher than those retrieved in spring and winter. [ABSTRACT FROM AUTHOR]

Objectives: Intimal hyperplasia is a serious clinical problem associated with the failure of therapeutic methods in multiple atherosclerosis-related coronary heart diseases, which are initiated and aggravated by the polarization of infiltrating macrophages. The present study aimed to determine the effect and underlying mechanism by which tumor necrosis factor receptor-associated factor 5 (TRAF5) regulates macrophage polarization during intimal hyperplasia. Methods: TRAF5 expression was detected in mouse carotid arteries subjected to wire injury. Bone marrow-derived macrophages, mouse peritoneal macrophages and human myeloid leukemia mononuclear cells were also used to test the expression of TRAF5 in vitro. Bone marrow-derived macrophages upon to LPS or IL-4 stimulation were performed to examine the effect of TRAF5 on macrophage polarization. TRAF5-knockout mice were used to evaluate the effect of TRAF5 on intimal hyperplasia. Results: TRAF5 expression gradually decreased during neointima formation in carotid arteries in a time-dependent manner. In addition, the results showed that TRAF5 expression was reduced in classically polarized macrophages (M1) subjected to LPS stimulation but was increased in alternatively polarized macrophages (M2) in response to IL-4 administration, and these changes were demonstrated in three different types of macrophages. An in vitro loss-of-function study with TRAF5 knockdown plasmids or TRAF5-knockout mice revealed high expression of markers associated with M1 macrophages and reduced expression of genes related to M2 macrophages. Subsequently, we incubated vascular smooth muscle cells with conditioned medium of polarized macrophages in which TRAF5 expression had been downregulated or ablated, which promoted the proliferation, migration and dedifferentiation of VSMCs. Mechanistically, TRAF5 knockdown inhibited the activation of anti-inflammatory M2 macrophages by directly inhibiting PPARγ expression. More importantly, TRAF5-deficient mice showed significantly aggressive intimal hyperplasia. Conclusions: Collectively, this evidence reveals an important role of TRAF5 in the development of intimal hyperplasia through the regulation of macrophage polarization, which provides a promising target for arterial restenosis-related disease management. [ABSTRACT FROM AUTHOR]

Background: Although most adults are infected by Epstein‐Barr virus (EBV), some patients develop highly lethal diseases associated with EBV infection, including EBV‐hemophagocytic lymphohistiocytosis (EBV‐HLH), chronic active EBV infections (CAEBV), and lymphoma, the pathogeneses of which remain to be investigated. The human leukocyte antigen (HLA) complex may be associated with the viral infection pathway, and, therefore, HLA alleles may be associated with EBV‐related diseases and subpopulations of infected cells, studies related to EBV‐associated diseases, and subpopulations of infected cells that were conducted in China are scarce. Methods: In this study, we analyzed the high‐resolution HLA genotypes of 269 patients with EBV‐associated diseases and 213 EBV‐seronegative hematopoietic stem cell donors using PCR‐SBT assay and elucidated the associations of HLA‐A, ‐B, ‐C, ‐DRB1, and ‐DQB1 alleles with EBV‐associated diseases in the Chinese population, Benjamini–Hochberg correction to adjust for multiple testing. HLA genotypes were also analyzed in patients with EBV‐associated diseases showing EBV‐infected lymphocyte subpopulations. Results: We found that individuals carrying the following alleles showed the following levels of risks: HLA‐DRB1*11 allele, reduced risk of EBV‐related disease (OR [odds ratio]: 0.56; 95% confidence interval [95% CI]: 0.32–0.99; p <.05; Adjust p =.71); HLA‐DQB1*06:02 allele, reduced risk (OR: 0.5699; 95% CI: 0.3486–0.9317; p <.05; Adjust p =.57); and HLA‐B*15:01 allele, increased risk (OR: 1.763; 95% CI: 0.3486–0.9317; p <.05; Adjust p =.57). Patients with EBV‐associated diseases showing the B*15:01 genotype had a higher risk of T‐cell, NK‐cell, and multicell infections than those with other genotype subgroups. Conclusions: These findings highlight the importance of HLA genotype for assessing EBV infectivity. [ABSTRACT FROM AUTHOR]

Plant rhizosphere microbes are closely related to plant growth, whereas how the rhizosphere microbial community affects root development remains poorly understood. In this study, 16S rRNA gene high-throughput sequencing technology was used to detect the bacterial community of tobacco rhizosphere, and to explore the association mechanism between different developmental conditions of tobacco roots and differences in rhizosphere microbial community. The results showed that the species richness and diversity of rhizosphere bacteria in the well-developed root system (WDR) were higher than those in the undeveloped root system (UDR), with the genera Gallionella and Luteimona significantly increased, while the genera Edaphobaculum, PLTA13 and Rhodobacter significantly increased. Abundance significantly reduced (P<0.05). The molecular ecological network of UDR is more complex, and the interaction between species is strong, especially the cooperative behavior. The number of key nodes in the WDR network is more, and its carbon cycle related network modules increase. In addition, the WDR rhizosphere bacterial community assembly tends to be more developmentally aggregated, and environmental filtering plays a more important role in it. Overall, the results of this study emphasize that the structural composition, network changes and community assembly of the rhizosphere microbial community play an important role in the development of plant roots, and provide a theoretical basis for regulating the rhizosphere microbial community to promote plant root growth. [ABSTRACT FROM AUTHOR]

Objectives: Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis is the most common type of infection-associated HLH. Previous studies were focused on pediatric EBV-HLH patients, therefore there lack of adult data. Method: We performed a retrospective analysis of 133 EBV-HLH patients (≥14 years old) in Beijing Friendship Hospital from March 2009 to April 2016 to evaluate the clinical manifestation and the effects and prognosis of existing regimens of EBV-HLH in adult and adolescents. Results: Of these patients, 91 male and 42 female cases had a median age of 26 (14-77) years. EBV-DNA load on admission was at a median of 6.6E + 05 IU/ml. The one-year mortality of these patients was 78%. 112 patients received the HLH-94/04 regimen as the initial treatment, 52 patients (46.43%) had response. Of the 6 patients who received the L-DEP regimen as the initial treatment, 5 patients (83.33%) had response. The rest 15 patients received initial treatment without etoposide, 5 cases achieved PR. 69 refractory or relapsed patients received DEP or L-DEP regimen, 55 (79.71%) cases had response. In addition, who received the L-DEP regimen, with the overall response rate significantly higher than the DEP regimen (88.37% VS 65.38%, P = 0.031). 36 out of 133 EBV-HLH patients eventually received allo-HSCT, with the overall survival rate of 52.78%. In summary, EBV-HLH is a highly lethal disease. Conclusion: DEP/L-DEP was a good salvage treatment. L-DEP might be a more effective first-line initial regimen than HLH-94/04 regimen for EBV-HLH. Finally, allo-HSCT is an effective radical treatment for EBV-HLH. [ABSTRACT FROM AUTHOR]