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Abstract The preclinical study of atherosclerosis has traditionally centred around the use of small animal models, translating to large animal models, prior to first-in-man studies. We propose to disrupt this paradigm by designing an ex vivo pump perfused human limb model. The novel model consists of taking a freshly amputated limb and incorporating it into an ex situ pump-perfused bypass system (akin to extracorporeal membrane oxygenation), circulating warmed, oxygenated blood. The circuit incorporates an introducer sheath and guiding catheter for intravascular imaging and X-ray angiography. Regular monitoring is performed using blood gas analysis, aiming for physiological parameters. The model maintains oxygen saturations > 99% for the length of perfusion (up to 6-h). Clinical grade X-ray angiography, intravascular ultrasound and optical coherence tomography have been successfully performed. Indocyanine green, a near-infrared fluorescent dye that localises to atherosclerotic plaque, has been injected into the system and left to circulate for 90-min. Fluorescence reflectance imaging of the dissected arterial bed confirmed uptake in areas of calcific atherosclerotic plaque on intravascular imaging. This is the first demonstration of an ex vivo pump-perfused “living” limb experimental model of atherosclerosis, which shows promise for future studies in translational interventional imaging and molecular targeting.

To improve the assimilation accuracy of satellite microwave observations, it is necessary to conduct precipitation detection before assimilation and exclude the data contaminated by the scattering of hydromorphic particles. The induction of microwave scattering is closely related to the effective radius of hydromorphic particles, and the motion state of hydromorphic particles at different scales can directly affect the internal dynamic structure of clouds, which will lead to precipitation. To further analyze and validate the impact of microwave scattering in a precipitation environment on the assimilation of satellite microwave soundings within the temperature-sensitive band, this article utilized the on-orbit observations of Microwave Temperature Sounder-III (MWTS-III) and Medium Resolution Spectral Imager onboard the Fengyun-3E (FY-3E) satellite to achieve multispectral fusion observation and precipitation detection over oceans, combined with the vertical dynamic characteristics of global numerical forecast in the cloud environment of China Meteorological Administration (CMA) Global Forecast System (CMA-GFS). By conducting the dynamic analysis of the hydrometeors in the cloud, the maximum possible effective particle radius of hydromorphic particles under the no-phase-transition condition and internal vertical motion is obtained. The consistency of the cloud liquid water path (CLWP) retrieved by MWTS-III and multispectral fusion precipitation detection is evaluated subsequently. The results show that the distribution of hydrometeors in the CMA-GFS forecast is broadly in line with the CLWP distribution obtained from the MWTS-III retrieval, regardless of Mie scattering or Rayleigh scattering. However, compared with Mie scattering, the weak convection of CMA-GFS shows better adaptability in the Rayleigh environment.

Abstract Background Intelligent cardiotocography (CTG) classification can assist obstetricians in evaluating fetal health. However, high classification performance is often achieved by complex machine learning (ML)-based models, which causes interpretability concerns. The trade-off between accuracy and interpretability makes it challenging for most existing ML-based CTG classification models to popularize in prenatal clinical applications. Methods Aiming to improve CTG classification performance and prediction interpretability, a hybrid model was proposed using a stacked ensemble strategy with mixed features and Kernel SHapley Additive exPlanations (SHAP) framework. Firstly, the stacked ensemble classifier was established by employing support vector machines (SVM), extreme gradient boosting (XGB), and random forests (RF) as base learners, and backpropagation (BP) as a meta learner whose input was mixed with the CTG features and the probability value of each category output by base learners. Then, the public and private CTG datasets were used to verify the discriminative performance. Furthermore, Kernel SHAP was applied to estimate the contribution values of features and their relationships to the fetal states. Results For intelligent CTG classification using 10-fold cross-validation, the accuracy and average F1 score were 0.9539 and 0.9249 in the public dataset, respectively; and those were 0.9201 and 0.8926 in the private dataset, respectively. For interpretability, the explanation results indicated that accelerations (AC) and the percentage of time with abnormal short-term variability (ASTV) were the key determinants. Specifically, the probability of abnormality increased and that of the normal state decreased as the value of ASTV grew. In addition, the likelihood of the normal status rose with the increase of AC. Conclusions The proposed model has high classification performance and reasonable interpretability for intelligent fetal monitoring.

Polymeric carbon nitride (PCN) is a kind of polymeric semiconductor that is widely popular in photocatalysis-related energy and environmental fields. However, the photocatalytic activity is still limited due to its poor conductivity and low charge separation efficiency. In this work, benzene rings were introduced to adjust the electronic structure of PCN, and then a PCN-based all-solid Z-scheme heterojunction was fabricated by combing multiwall carbon nanotubes (CNTs) and ferric oxide through precipitation and the in situ deposit method. Upon optimizing the ratio between PCN, CNTs, and Fe2O3, (PCN:CNTs:Fe2O3 = 10:1:3 by weight), the composites expressed superior photocatalytic degradation activity towards methylene blue (MB) and crystal violet (CV) compared with pristine PCN and Fe2O3. The MB degradation percentage achieved 90% in 75 min, and the CV up to 99.6% within 50 min. The Z-scheme mechanism was verified by band alignment and metal selective deposition. The CNTs in the heterojunction played the role of an electron shuttling mediator and hence improved charge separation efficiency. This work provides ideas for the construction of polymer-inorganic all-solid Z-scheme photocatalysts for practical applications.

Prior to assimilating hyperspectral infrared data on the FengYun (FY) satellite in the numerical weather prediction (NWP) system, it is necessary to identify the quality and bias characteristics of these data, especially as China’s first early-morning-orbit satellite data. Using the numerical model CMA-GFS (China Meteorological Administration Global Forecast System) and the observation of FY-3E HIRAS-II (Hyperspectral Infrared Atmospheric Sounder-II), the differences between observed and simulated brightness temperatures (O-Bs) are comprehensively analyzed, with a focus on evaluating the long-wave (LW) temperature sounding channels of HIRAS-II observation in the clear sky. The results show that the O-Bs in the LW channels are between ±1.0 K, except for the CO2 absorption line peak at 667 cm−1. Only a tiny variation in O-Bs, with relative consistency, could be observed during the day, the line of dawn and dusk, and night. The difference in the standard deviations of O-Bs in the three cases is less than 0.1 K. The O-Bs of two typical channels (channels 14 and 47) in the stratosphere have disturbances at individual times, whereas the O-Bs are much more stable in time series in the tropospheric channels. The O-Bs in different channels show the characteristics of changing with the latitude, but the bias and standard deviations of O-Bs during the ascending and descending stages are not much different, except for the bias of channel 47 in low latitude. The optimal ranking of Fields of View (FOVs) in assimilation is derived from a priori analysis of O-Bs. The results demonstrate that FOV4 and FOV5 are the best in a Field of Regard (FOR) compared to all LW channels of HIRAS-II in constructions of their O-Bs and magnitude of O-B standard deviations, and they can be used as the preferred FOVs for assimilation. While the O-Bs in FOV1 and FOV2 are slightly larger, the O-Bs’ characteristics also meet the assimilation requirements and can be used as assimilation FOVs in HIRAS-II LW channels after FOV4 and FOV5 lose their efficacy.

Associated microbes of several herbivorous insects can improve insect fitness. However, the contribution of specific insect gut bacterium to plant toxin toxification for its host fitness remains scarce. Here, a gut bacterium Raoultella terrigena from the ghost moth Thitarodes xiaojinensis larvae was identified. This bacterium grew unhindered in the presence of Polygonum viviparum, which is a natural food for ghost moth larvae but showed significant growth inhibition and toxicity against Spodoptera litura. S. litura reared on artificial diets containing 5, 15 and 25% P. viviparum powder after 7 days coculture with R. terrigena were found to have shorter larval and pupal durations than on the diets containing P. viviparum powder but without R. terrigena coculture. HPLC analysis revealed that the content of quercetin in mineral medium containing 15% P. viviparum powder after 7 days coculture with R. terrigena was significantly decreased (79.48%) as compared with that in P. viviparum powder without R. terrigena coculture. In vitro fermentation further verified that R. terrigena could degrade 85.56% quercetin in Lucia-Bertani medium. S. litura reared on artificial diets containing 0.01, 0.05 and 0.1 mg/g quercetin after 48 h coculture with R. terrigena were also found to have shorter larval, prepupal and pupal durations, as well as higher average pupal weight and adult emergence rate than on the diets containing quercetin, but without R. terrigena coculture. In addition, R. terrigena was detected in the bud and root tissues of the sterilized P. viviparum, indicating that T. xiaojinensis larvae might acquire this bacterium through feeding. These results demonstrate that the gut bacteria contribute to the degradation of plant toxic molecules to improve the development of herbivorous insects and provide fundamental knowledge for developing effective methods for beneficial insect rearing and pest control.

Chronic obstructive pulmonary disease (COPD) is a common, preventable, and treatable disease. The incidence of COPD is growing annually in China, and it is a significant and growing public health burden. Multivariate analysis showed that COPD was one of the independent risk factors for the occurrence of pulmonary embolism (PE), and the incidence of PE was significantly higher in COPD patients than in normal subjects. However, PE is often overlooked in patients with acute exacerbation of COPD (AECOPD) because there are many similarities in clinical symptoms between PE and AECOPD, which are difficult to distinguish, resulting in the failure of timely treatment and poor prognosis. Therefore, it is of great significance to understand the clinical manifestations, diagnosis, and treatment of COPD combined with PE for making a more accurate diagnosis, providing timely and effective treatment, and improving the prognosis of such patients.

Fine spectral detection can basically solve the problem of low vertical resolution at the 183 GHz water-vapor absorption line, and it is expected to become one of the main methods for next-generation geostationary and polar-orbiting satellites. Here, using data from Microwave Humidity Sounder II (MWHS-II) onboard the Chinese Fengyun 3D (FY-3D) satellite in the Global/Regional Assimilation and Prediction System (GRAPES) Four-Dimensional Variational (4D-Var) system of the China Meteorological Administration (CMA), we explore the assimilation application of the water-vapor absorption line at 183.31 ± 1 GHz, 183.31 ± 3 GHz and 183.31 ± 7 GHz, as well as 183.31 ± 1.8 GHz and 183.31 ± 4.5 GHz, two added channels, to assess the impact of adding the 183.31 ± 1.8 GHz and 183.31 ± 4.5 GHz sampling channels on data assimilation and numerical weather prediction. Our findings reveal a significant increase in the specific-humidity increment, which in the middle–upper troposphere is numerically much larger than in the lower troposphere. Specifically, the assimilation of 183.31 ± 1.8 GHz observations, positioned near the center of the water-vapor absorption line, results in a pronounced adjustment compared with the 183.31 ± 4.5 GHz observations. And under the strong constraint of the numerical model, the Root Mean Square Error (RMSE) of the wind field diminishes more significantly (by an average of 2–4%) after assimilating the water-vapor observations at greater heights.

On 5 July 2021, China launched the world’s first early morning orbit meteorological satellite, which was equipped with China’s newest-generation microwave instrument, the Microwave Temperature Sounder-3 (MWTS-3). MWTS-3 has 17 detection channels, which can detect temperature profiles from near the ground to approximately 2 hPa. However, similar to the newest-generation microwave temperature instruments in other countries, MWTS-3 may also suffer from striping noise. In this paper, a principal component analysis (PCA) is combined with ensemble empirical mode decomposition (EEMD) to extract the striping noise from the brightness temperatures observed by MWTS-3, and a comparative analysis is performed with its predecessor (MWTS-2). This paper analyzes the characteristics of the striping noise of both instruments and its possible impact on their observations. The results show that the striping noise of MWTS-3 has been significantly reduced in most of the 17 channels. In particular, the striping noise of MWTS-3’s channel 3 is reduced by nearly half compared to the channel of MWTS-2 with the same frequency. Furthermore, the interchannel correlations for MWTS-3 are significantly lower than those for MWTS-2. After noise mitigation, the interchannel correlations of both MWTS-2 and MWTS-3 are obviously reduced. In addition, striping noise mitigation can reduce observation errors to some extent, especially for channels above the middle troposphere.

Chronic constrictive pericarditis (CCP) is one of the common causes of cardiogenic cirrhosis; it is rare for a patient to have both CCP and recurrent black stool, so we consider that CCP causes cardiogenic cirrhosis. Cardiogenic cirrhosis caused portal hypertension which then resulted in gastrointestinal bleeding. Herein, we report a case of a 40-year-old Chinese woman suffering from CCP who had upper gastrointestinal bleed and had to undergo emergency surgery. Two years after the emergency surgery, multiple reexaminations showed significantly improved cardiac functions, hemoglobin, and WBC levels and gastrointestinal functions.

FengYun-3E (FY-3E), the fifth satellite in China’s second-generation polar-orbiting satellite FY-3 series, was launched on 5 July 2021. FY-3E carries a third-generation microwave temperature sounder (MWTS-3). For the first time, this study demonstrates that MWTS-3 radiances data assimilation can improve the China Meteorological Administration Global Forecast System (CMA-GFS). By establishing a cloud detection module based on the retrieval results of the new channels of MWTS-3, a quality control module according to the error characteristics of MWTS-3 data, and a bias correction module considering the scanning position of satellite and weather systems, the effective assimilation of MWTS-3 data in the CMA-GFS has been realized. Through one-month cycling experiments of assimilation and forecasts, the error characteristics and assimilation effects of MWTS-3 data are carefully evaluated. The results show that the observation errors in MWTS-3 data are similar to those in advanced technology microwave sounder (ATMS) data within the same frequency channel, are slightly larger than those in the advanced microwave-sounding unit-A (AMSU-A) data, and are much better than those in the MWTS-2 data. The validation of the assimilation and prediction results demonstrate the positive contribution of MWTS-3 data assimilation, which can remarkably reduce the analysis errors in the Northern and Southern Hemispheres. Specifically, the error growth on the upper layer of the model is obviously suppressed. When all other operational satellite observations are included, the assimilation of MWTS-3 data has a neutral or slightly positive contribution to the analysis and forecast results, and the improvement is mainly found in the Southern Hemisphere. The relevant evaluation results indicate that the MWTS-3 data assimilation has good application prospects for operation.

The FY-3E satellite was successfully launched on 5 July 2021 and carries on board the Microwave Temperature Sounder-III (MWTS-III). In this study, the biases of MWTS-III data with respect to simulations are analyzed according to the instrument field of view and location latitude over the Pacific region. The cloud liquid water path (CLWP) over oceans is retrieved from two new window channels at 23.8 and 31.4 GHz and is used for detecting the clouds-affected microwave sounding data. The absolute bias between the observed and simulated brightness temperature (O–B) under the clear sky point is, in general, less than 2.0 K, depending on the MWTS-III channel. The standard deviations of O-B in most channels are less 1.0 K, but they are 1–1.5 K in channels 1–4 and 17. The average and the standard deviation of O−B from the channels 1–10 shows an obvious symmetrical variation with FOV. The evaluation results all indicate good prospects for the assimilation application of FY-3E microwave sounding data.

The spent automobile catalysts (SAC) is the major secondary source of palladium and the production of SAC is increasing rapidly over years. The price of palladium keeps rising over the years, which demonstrates its preciousness and urgent industrial demand. Recovering palladium from the spent automobile catalysts benefits a lot from economic and environmental protection aspects. This review aims to provide some new considerations of recovering palladium from the spent automotive catalysts by summarizing and discussing both hydrometallurgical and pyrometallurgical methods. The processes of pretreatment, leaching/extraction, and separation/recovery of palladium from the spent catalysts are introduced, and related reaction mechanisms and process flows are given, especially detailed for hydrometallurgical methods. Hydrometallurgical methods such as chloride leaching with oxidants possess a high selectivity of palladium and low consumption of energy, and are cost-effective and flexible for different volume feeds compared with pyrometallurgical methods. The recovery ratios of palladium and other platinum-group metals should be the focus of competition since their prices have been rapidly increased over the years, and hence more efficient extractants with high selectivity of palladium even in the complexed leachate should be proposed in the future.

By employing a culture-dependent and -independent 16S rRNA and ITS gene high-throughput sequencing analyses, comprehensive information was obtained on the gut bacterial and fungal communities in the ghost moth larvae of three different geographic locations from high-altitude on Tibet plateau and from low-altitude laboratory. Twenty-six culturable bacterial species belonging to 21 genera and 14 fungal species belonging to 12 genera were identified from six populations by culture-dependent method. Carnobacterium maltaromaticum was the most abundant bacterial species from both the wild and laboratory-reared larvae. The most abundant OTUs in the wild ghost moth populations were Carnobacteriaceae, Enterobacteriaceae for bacteria, and Ascomycota and Basidiomycota for fungi. Larval microbial communities of the wild ghost moth from different geographic locations were not significantly different from each other but significant difference in larval microbial community was detected between the wild and laboratory-reared ghost moth. The larval gut of the wild ghost moth was dominated by the culturable Carnobacterium. However, that of the laboratory-reared ghost moth exhibited significantly abundant Wolbachia, Rhizobium, Serratia, Pseudomonas, and Flavobacterium. Furthermore, the larval gut of the wild ghost moth had a significantly higher abundance of Ophiocordyceps but lower abundance of Candida and Aspergillus than that of the laboratory-reared ghost moth.

O-isopropyl-N-ethyl thionocarbamate (IPETC) collector was used to selectively recover elemental sulfur from a high-sulfur residue, and its flotation performance, structure–property relationship and adsorption mechanism to elemental sulfur were studied. The raw ore flotation test showed that IPETC displayed superior flotation performance to the elemental sulfur compared with sodium ethyl xanthate (SEX) and ammonium dibutyl dithiophosphate (ADDTP) collectors. Pure mineral flotation and adsorption experiments further demonstrated that among the three collectors, IPETC had the strongest collecting power and the optimum selectivity towards elemental sulfur. The structure–property relationship research based on density functional theory (DFT) calculation supported the above conclusion. The adsorption mechanism analysis manifested that IPETC adsorption on elemental sulfur surface was a chemical process by separately generating normal covalent bond between carbonyl S atom and S atom and a backdonation covalent bond between O atom and S atom, which was confirmed by the FTIR spectrum analysis result. IPETC exhibits excellent collecting ability and selectivity for elemental sulfur and therefore it has bright application prospects.

An efficient flotation process was developed to selectively recover elemental sulfur from a high-sulfur pressure acid leaching residue of zinc sulfide concentrate. The process mineralogy analysis showed that the sulfur content reached 46.21%, and 81.97% of the sulfur existed as elemental sulfur which was the major mineral in the residue and primarily existed as pellet aggregate and biconical euhedral crystal. An elemental sulfur concentrate product with 99.9% of recovery and 83.46% of purity was obtained using the flotation process of one-time blank rougher, two-time agent-added roughers, and two-time cleaners with Z-200 as collector and Na2S + ZnSO4 + Na2SO3 as depressant. The flotation experiment using return water indicated that the cycle use of return water had no adverse effect on the flotation performance of elemental sulfur. The process mineralogy analysis manifested that main minerals in the residue directionally went into the flotation products. Most of elemental sulfur entered the concentrate while other minerals almost completely went into the tailing. Main valuable elements lead, zinc, and silver entered the tailing with sulfides and could be recovered by lead smelting. The proposed process can realize the comprehensive recovery of valuable components in the high-sulfur residue and thus it has wide industrial application prospect.

The entomopathogenic fungus Ophiocordyceps sinensis is one of the best known and most precious medicines and health food in China. The blastospores-hyphae (dimorphism) transition of this fungus in host hemolymph is critical for the virulence and the mummification of host larvae. To regulate this transition, the effects of inoculum density and fifteen chemicals including fungal nutrients, fungal metabolites, quorum-sensing molecules (QSMs) and insect hormones on the dimorphism in O. sinensis were investigated in vitro. The blastospores tended to exhibit budding growth when inoculated at 107 blastospores per mL, and hyphal growth at concentrations lower than 106 blastospores per mL. At 105 blastospores per mL, the percentage of hyphal formation decreased with the addition of filtered spent medium containing 107 blastospores per mL, indicating the quorum-sensing effect. Blastospores-hyphae transition in this fungus by fifteen chemicals was varied from no response to dimorphic reversion. The addition of N-acetylglucosamine at three concentrations significantly stimulated hyphal formation while inhibiting budding growth. For the first time, insect hormone 20-hydroxyecdysone was found to be involved in the hyphal formation in fungi. These results open new possibilities to regulate the dimorphism, which would be beneficial for the cultivation of the Chinese cordyceps.

Time-interleaved analog-to-digital converter (TIADC) is a good option for high sampling rate applications. However, the inevitable sample-and-hold (S/H) mismatches between channels incur undesirable error and then affect the TIADC’s dynamic performance. Several calibration methods have been proposed for S/H mismatches which either need training signals or have less extensive applicability for different input signals and different numbers of channels. This paper proposes a statistics-based calibration algorithm for S/H mismatches in M-channel TIADCs. Initially, the mismatch coefficients are identified by eliminating the statistical differences between channels. Subsequently, the mismatch-induced error is approximated by employing variable multipliers and differentiators in several Richardson iterations. Finally, the error is subtracted from the original output signal to approximate the expected signal. Simulation results illustrate the effectiveness of the proposed method, the selection of key parameters and the advantage to other methods.

Reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) is the sensitive method to quantify the expression levels of target genes on the basis of endogenous control. An appropriate reference gene set for normalization is essential for reliable results. The ghost moth, Thitarodes armoricanus, a host species of a medicinal fungus, Ophiocordyceps sinensis, is an economically important member of the Lepidoptera. Recent studies have focused on the mechanism of adaptation of this species to its high-altitude environment and host immune response to O. sinensis infection and RT-qPCR is commonly used in these studies to decipher the genetic basis of physiological functions. However, a thorough assessment of candidate reference genes in the genus Thitarodes is lacking. Here, the expression levels of eight candidate reference genes (ACT, EF, EIF4A, GAPDH, G6PDH, RPL13A, TUB and 18S) in T. armoricanus at different developmental stages and in different body parts of the seventh instar larvae were analyzed, along with larvae kept under low temperatures, larvae exposed to two fungal infections and larvae fed different diets. Three established software programs-Bestkeeper, geNorm and NormFinder-were employed to calculate variation among the treatments. The results revealed that the best-suited reference genes differed across the treatments, with EF, EIF4A and GAPDH found to be the best suited for the different developmental stages and larvae body parts; EF, EIF4A and RPL13A found to be the best suited for low-temperature challenge; and EF, EIF4A and TUB found to be the best suited for the fungal infections and dietary treatments. This study thus further contributes to the establishment of an accurate method for normalizing RT-qPCR results for T. armoricanus and serves as a reference for gene expression studies of related insect species.

The transformer (tra) gene appears to act as the genetic switch that promotes female development by interaction with the transformer2 (tra-2) gene in several dipteran species including the Medfly, housefly and Drosophila melanogaster. In this study, we describe the isolation, expression and function of tra and tra-2 in the economically important agricultural pest, the oriental fruit fly, Bactrocera dorsalis (Hendel). Bdtra and Bdtra-2 are similar to their homologs from other tephritid species. Bdtra demonstrated sex-specific transcripts: one transcript in females and two transcripts in males. In contrast, Bdtra-2 only had one transcript that was common to males and females, which was transcribed continuously in different adult tissues and developmental stages. Bdtra-2 and the female form of Bdtra were maternally inherited in eggs, whereas the male form of Bdtra was not detectable until embryos of 1 and 2 h after egg laying. Function analyses of Bdtra and Bdtra-2 indicated that both were indispensable for female development, as nearly 100% males were obtained with embryonic RNAi against either Bdtra or Bdtra-2. The fertility of these RNAi-generated males was subsequently tested. More than 80% of RNAi-generated males could mate and the mated females could lay eggs, but only 40-48.6% males gave rise to progeny. In XX-reversed males and intersex individuals, no clear female gonadal morphology was observed after dissection. These results shed light on the development of a genetic sexing system with male-only release for this agricultural pest.