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To provide reference and theoretical guidance for establishing human body dynamics models and studying biomechanical vibration behavior, this study aimed to develop and verify a computational model of a three-dimensional seated human body with detailed anatomical structure under complex biomechanical characteristics to investigate dynamic characteristics and internal vibration behaviors of the human body. Fifty modes of a seated human body were extracted by modal method. The intervertebral disc and head motions under uniaxial white noise excitation (between 0 and 20 Hz at 1.0, 0.5 and 0.5 m/s2 r.m.s. for vertical, fore-aft and lateral direction, respectively) were computed by random response analysis method. It was found that there were many modes of the seated human body in the low-frequency range, and the modes that had a great impact on seated human vibration were mainly distributed below 13 Hz. The responses of different positions of the spine varied greatly under the fore-aft and lateral excitation, but the maximum stress was distributed in the lumbar under different excitations, which could explain why drivers were prone to lower back pain after prolonged driving. Moreover, there was a large vibration coupling between the vertical and fore-aft direction of an upright seated human body, while the vibration couplings between the lateral and other directions were very small. Overall, the study could provide new insights into not only the overall dynamic characteristics of the human body, but also the internal local motion and biomechanical characteristics under different excitations. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the prognostic utility of Activity-dependent neuroprotective protein (ADNP) expression in Circulating Tumor Cells (CTCs) inpatients with Non-muscle-invasive Bladder Cancer (NMIBC) undergoing Transurethral Resection of Bladder Tumor (TURBT). A prospective cohort of 74 bladder cancer patients and 22 non-cancer controls were enrolled. The expression of ADNP mRNA was detected by immunomagnetic beads-droplet digital PCR. The ADNP mRNA expression was evaluated in patients with high-risk NMIBC and those with indeterminate invasion depth post 2nd TURBT. Primary cultured bladder cancer cells and PBMCs from healthy donors were immunofluorescence stained. Our findings suggest that baseline ADNP mRNA level in CTCs shows potential as a prognostic marker for NMIBC with a sensitivity of 83.33% and a specificity of 73.58%. In comparison to baseline, ADNP mRNA expression increased post 2nd TURBT in 5 patients, where 2 experienced recurrence. Meanwhile, among the 12 patients with decreased levels, only one patient relapsed. A considerable limitation of this study entails the small sample size. The Immuno-magnetic beads-ddPCR technique provided a viable method for ADNP mRNA detection in CTCs from bladder cancer patients. The preoperative ADNP mRNA level in CTCs was identified as a prognostic indicator for NMIBC. Longitudinal monitoring of ADNP mRNA in CTCs of bladder cancer patients shows promise in evaluating treatment responses and predicting prognosis. [ABSTRACT FROM AUTHOR]

Purpose: Selective tibial neurotomy (STN) is a surgical procedure for treating spastic equinovarus foot. Hyperselective neurectomy (HSN) of tibial nerve is a modified STN procedure, which was rarely discussed. This study aimed to describe the branching patterns of the tibial nerve and propose an optimal surgical incision of HSN for treatment of spastic equinovarus foot. Methods: Sixteen lower limbs were dissected to determine the various branching patterns of the tibial nerve and categorized according to these branching patterns. The mean distances from the nerve entry points to the tip of femur's medial epicondyle were measured, as well as their percentage to the overall length of the leg. The surgical incision was designed according to the range of these nerve entry points. Results: The tibial nerve sent out proximal and distal motor branches based on their position relative to the soleus muscle's tendinous arch. For proximal motor branches, the branches innervating the medial gastrocnemius, lateral gastrocnemius and proximal soleus were categorized into types I (9/16), II (5/16) and III (2/16). Measurements from the medial epicondyle to the nerve entry points into the medial gastrocnemius, lateral gastrocnemius and proximal soleus ranged from 14 to 33 mm (4–9% of leg length), 22–45 mm (6–12%) and 35–81 mm (10–22%), respectively. Distal motor branches including the distal soleus, posterior tibialis, flexor digitorum longus and flexor hallucis longus, were classified as types A (8/14), B (4/14) and C (2/14), with the distances from their respective terminal points to the medial epicondyle were 67–137 mm (19–39%), 74–125 mm (20–35%), 116–243 mm (33–69%) and 125–272 mm (35–77%). Conclusions: The motor branches of tibial nerve were classified into two groups and each subdivided into three types. Detailed location parameters may serve as an anatomical basis for designing incision of HSN. [ABSTRACT FROM AUTHOR]

Based on the MnOx/TiO2 catalyst prepared by the sol–gel method as the substrate, the impregnation method was used to simulate the deactivation process of the alkali metal K of the MnOx/TiO2 catalyst, and the regeneration experiment of the deactivated K–MnOx/TiO2 catalyst was carried out by water washing and acid washing. The effects of methods and process conditions on the regeneration effect of deactivated catalysts were discussed emphatically. The results show that the regeneration effect of acid washing on the deactivated catalyst is obviously better than that of water washing. Under the conditions of ultrasonic frequency of 30 kHz, HNO3 concentration of 0.3 mol l–1, acid washing for 45 min and calcination at 400°C for 4 h, the removal rate of NO by the catalyst can be recovered from 35 to 89%. Using Brunauer–Emmett–Teller and Barren–Johner–Halendar analysis, X-ray fluorescence analysis, and NH3 temperature-programmed desorption analysis, it was found that acid washing can better restore the specific surface area and surface acid content of the deactivated catalyst, and has a strong ability to remove alkali metal K. [ABSTRACT FROM AUTHOR]

Iron overload has been associated with an increased risk of COVID-19 severity and mortality in observational studies, but it remains unclear whether these associations represent causal effects. We performed a two-sample Mendelian randomization (MR) to determine associations between genetic liability to iron overload and the risk of COVID-19 severity and mortality. From genome-wide association studies of European ancestry, single-nucleotide polymorphisms associated with liver iron (n = 32,858) and ferritin (n = 23,986) were selected as exposure instruments, and summary statistics of the hospitalization (n = 16,551) and mortality (n = 15,815) of COVID-19 were utilized as the outcome. We used the inverse-variance weighted (IVW) method as the primary analysis to estimate causal effects, and other alternative approaches as well as comprehensive sensitivity analysis were conducted for estimating the robustness of identified associations. Genetically predicted high liver iron levels were associated with an increased risk of COVID-19 mortality based on the results of IVW analysis (OR = 1.38, 95% CI: 1.05–1.82, P = 0.02). Likewise, sensitivity analyses showed consistent and robust results in general (all P > 0.05). A higher risk of COVID-19 hospitalization trend was also observed in patients with high liver iron levels without statistical significance. This study suggests that COVID-19 mortality might be partially driven by the iron accumulation in the liver, supporting the classification of iron overload as one of the independent death risk factors. Therefore, avoiding iron overload and maintaining normal iron levels may be a powerful measure to reduce COVID-19 mortality. [ABSTRACT FROM AUTHOR]

The fluid kinematics of Liutex decomposes a velocity gradient tensor (VGT) of ∇v into four components, including rotation (R), stretching/compressing (SC), anti-symmetric shear (Santi-sym) and symmetric shear (Ssym), as oppose to the traditional Cauchy-Stokes decomposition where a VGT was decomposed into the strain rate and vorticity tensors. The current study limpidly clarified the physical meanings of these deformations in the newly-proposed decomposition from the perspectives of both fluid kinematics and dynamics. With in-depth understanding the physical connotations of these deformations, the present study further suggests that the Ssym be the only deformation appropriately correlated to the stress tensor, leading to the establishment of a new constitutive relation for Newtonian fluids with the modified model assumptions originated from Stokes in 1845. Moreover, the present research finds that the "principal decomposition" proposed by Liu is not mathematically unique when a VGT has three real eigenvalues (TR). Within the context, a new decomposition method is introduced to avoid the non-uniqueness issue arising from using the principal decomposition to establish fluid dynamics equations. Based on the modified Stokes assumptions and the novel VGT decomposition method, a set of new fluid dynamics momentum equations are obtained for Newtonian fluid. The added stress tensor of Fadd is identified as the key difference between the newly-derived governing equations and the conventional Navier-Stokes (N-S) equations, which is caused by excluding the SC correlation to the stress tensor in the new constitutive equation. Finally, a preliminary analysis of Fadd is conducted using the existing channel turbulence direct numerical simulations (DNS) data based on the traditional N-S equations. The Fadd is found widely existing in turbulence and is of the same order of magnitude with the other force terms. Therefore, the Fadd is expected to have some nonnegligible effects on altering the current DNS data based on the traditional N-S equations, which will be further verified by performing the "DNS" simulation using the newly-derived fluid dynamics equations in near future. [ABSTRACT FROM AUTHOR]

To assess the widely used submerged side-blowing in pyrometallurgy, a high-speed camera-digital image processing-statistical approach was used to systematically investigate the effects of the gas flow rate, nozzle diameter, and inclination angle on the space-time distribution and penetration behavior of submerged side-blown gas in an air-water system. The results show that the gas motion gradually changes from a bubbling regime to a steady jetting regime and the formation of a complete jet structure as the flow rate increases. When the flow rate is low, a bubble area is formed by large bubbles in the area above the nozzle. When the flow rate and the nozzle diameter are significant, a bubble area is formed by tiny bubbles in the area above the nozzle. The increased inclination angle requires a more significant flow rate to form a complete jet structure. In the sampling time, the dimensionless horizontal and vertical penetration depths are Gaussian distributed. Decreasing the nozzle diameter and increasing the flow rate or inclination angle will increase the distribution range and discreteness. New correlations for a penetration depth with an error of ±20% were obtained through dimensional analysis. The dimensionless horizontal penetration depth of an argon-melt system in a 120 t converter calculated by the correlation proposed by the current study is close to the result calculated by a correlation in the literature and a numerical simulation result in the literature. [ABSTRACT FROM AUTHOR]

Central nervous system (CNS) injuries, including stroke, traumatic brain injury, and spinal cord injury, are leading causes of long-term disability. It is estimated that more than half of the survivors of severe unilateral injury are unable to use the denervated limb. Previous studies have focused on neuroprotective interventions in the affected hemisphere to limit brain lesions and neurorepair measures to promote recovery. However, the ability to increase plasticity in the injured brain is restricted and difficult to improve. Therefore, over several decades, researchers have been prompted to enhance the compensation by the unaffected hemisphere. Animal experiments have revealed that regrowth of ipsilateral descending fibers from the unaffected hemisphere to denervated motor neurons plays a significant role in the restoration of motor function. In addition, several clinical treatments have been designed to restore ipsilateral motor control, including brain stimulation, nerve transfer surgery, and brain–computer interface systems. Here, we comprehensively review the neural mechanisms as well as translational applications of ipsilateral motor control upon rehabilitation after CNS injuries. [ABSTRACT FROM AUTHOR]

In bath smelting, the study of gas–liquid interaction and the local bubble characteristics is very important. Physical simulation is used to study the effect of the nozzle diameter, the number of lances, total gas flow rate, and the position of the measurement on the local bubble characteristics and gas–liquid interaction in the side-blown vortex smelting reduction reactor. The results show that as the total gas flow rate increases, the gas distribution range will expand, the location of the maximum gas holdup will be away from the lances. As the nozzle diameter decreases, the location of the maximum gas holdup will be away from the lances. When 6 lances are used, a bubble band with uniform bubble velocity distribution is generated in the jet control area. When using 3 lances, the uniformity of the bubble velocity distribution is worse than that when 6 lances are used, but the bubble velocity will be larger. As the total gas flow rate increases, the mean specific interfacial area in the reactor increases. When the total gas flow rate is high, using 3 lances will produce more interfacial area than using 6 lances. The empirical correlation of the local specific interfacial area is obtained. [ABSTRACT FROM AUTHOR]

We developed SMART v1.0 (http://smart.omicstudio.cloud), the first database for small molecules with functional implications in plants. The SMART database is devoted to providing and managing small molecules and their associated structural data, chemoinformatic data, protein targets, pathways and induced phenotype/function information. Currently, SMART v1.0 encompasses 1218 unique small molecules which are involved in multiple biological pathways. SMART v1.0 is featured with user-friendly interfaces, through which pathway-centered visualization of small molecules can be efficiently performed, and multiple types of searches (i.e., text search, structure similarity search and sequence similarity search) can be conveniently conducted. SMART v1.0 is also specifically designed to be a small molecule-sharing database, allowing users to release their newly discovered small molecules to public via the Contribute webpage. The SMART database will facilitate the comprehensive understanding of small molecules in complex biological processes in plants. [ABSTRACT FROM AUTHOR]

The side-blown vortex smelting reduction reactor proposed in this paper is a new type of metal extraction equipment. The study of fluid dynamics is significant for improving reactor performance. Physical simulation is used to analyze the effects of the angle and number of blown lances, nozzle diameter, gas flow rate, and measuring depths on the reactor's transfer and mixing characteristics. Dimensional analysis is used to correlate dimensionless numbers (Reynolds number Re, modified Froude number Fr′, capillary number Ca, number of blown lances n, and horizontal angle of the blown lance α) with mixing time and multiphase flow behavior. The results show that when the nozzle diameter and the number of blown lances are constant, Fr′, Ca and α are negatively correlated with the mixing time, and Re is positively correlated with the mixing time. When the angle of the blown lance is constant, Re and Ca are negatively correlated with mixing time, and Fr′ is positively correlated with mixing time. With the increase of Re, Fr′, Ca, the mixing behavior will gradually change from the bubbling regime to the transition regime and then to the steady jetting regime. [ABSTRACT FROM AUTHOR]

Purpose: Significant conflicts regarding prophylactic antifungal treatment in acute pancreatitis (AP) exist among current literatures and guidelines. The key to resolving this controversial issue is to identify risk factors for intra-abdominal fungal infection (AFI) among patients with AP. Methods: A single-center, retrospective cohort of 826 patients with AP between January 2014 to December 2019 was analysed to study the risk factors of AFI. Results: Of the 826 patients with AP, 10 patients (1.2%) developed AFI, including 2 cases in moderately severe AP (MSAP) and 8 in severe AP (SAP). The incidence of AFI was significantly higher in patients with SAP compared with MSAP and mild AP (10.3 vs. 0.8% vs. 0, P < 0.001). SAP patients with AFI were more likely to have multiple organ failure (MOF) (OR = 13.4; 95% CI 1.6–115.5), organ failure lasting more than 1 week (OR = 5.1; 95% CI 1.0–27.0), and surgical intervention within first week of admission (OR = 7.4; 95% CI 1.0–53.6). Multivariable analysis identified MOF (OR = 14.3; 95% CI 1.2–173.8) as the only independent risk factor of AFI. Conclusion: MOF might be the indication of prophylactic antifungal therapy in patients with AP. [ABSTRACT FROM AUTHOR]

Spark plasma diffusion welding (SPDW) is a powerful technique for joining materials at a remarkably short time with excellent quality. In this paper, SPDW of 5A06Al alloy to itself was conducted with Al–20Cu–5Si–2Ni brazing filler alloy added as the interlayer. In the bonding temperature ranging from 520 to 550°C, pressure from 0.3 to 6 MPa, and holding time from 10 to 20 min, the optimal joint was obtained at bonding temperature of 540°C and pressure of 6 MPa for 10 min. Results showed that the void-free 5A06Al/5A06Al-bonded joint was obtained at the optimized parameters with the aiding of electric current and Al–20Cu–5Si–2Ni interlayer. Increasing the bonding pressure produced more refined grains in the bonding joint and was therefore beneficial to the bonding quality. The formation of refined eutectic phases, the accelerated atomic diffusion, the sufficiently removal of oxide film, and the evidently more narrowed bonding interface areas were helpful to strengthen the SPDW joint. The most efficient bonding joint had a tensile strength of as high as 220 MPa and exhibited typical fine ductile dimple fractography. Comparatively, the poorest joint quality was obtained at lower bonding temperature and pressure, i.e., bonding temperature of 530°C, pressure of 0.3 MPa, and holding time of 10 min. [ABSTRACT FROM AUTHOR]

To explore distribution and epidemic characteristics of CVD in followed-up HP patients. Using the Hypertension Follow-up Management System database in Jiading district in Shanghai. We designed a retrospective cohort study that included all followed-up hypertension patients between 2002 and 2020. The endpoint was the occurrence of CVD confirmed by the hospital; otherwise, the patients were tracked until September 30, 2020. Record information of every patient has been collected in the registration card and each followed-up record. Among 223,097 observational followed-up HP patients, the total number of person years of observation was 4,244,421.25 person-year, 11,143 patients had developed CVD from hypertension before the deadline, the total incidence density was 0.00263 per person-year (male 0.00292; female 0.00238) and the complication ratio of CVD in HP patients was 4.99% (male 5.25%; female 4.76%) during follow-up period. The proportion of ischemic cerebrovascular, hemorrhagic cerebrovascular and unclassified stroke was respectively 71.18%, 5.95% and 22.87% in hypertensive CVD. Complication ratio of CVD increased with age, the group under 30 was 0, and the group over 70 was the highest (6.90%). The complication ratio of grad I, grad II and grad III blood pressure were respectively 4.79%, 4.96% and 6.13%. The complication ratio was 4.92% in only high systolic blood pressure patients; 17.23% in only high diastolic blood pressure patients; 4.59% in high systolic and diastolic blood pressure patients. The peak of complication ratio of CVD was 9–10 years after the registered and followed-up. The proportion of CVD cases in HP patients from April to June was the largest in the four seasons; the proportion of patients from October to December was the minimum. HP patient was prone to falling cerebrovascular disease; the main type of disease was cerebral infarction. Complication ratio in male incidence was higher than that in female. The complication ratio of CVD increased with age, blood pressure and duration of HP patients. It had seasonal characteristics, which was relatively high from April to June within year. [ABSTRACT FROM AUTHOR]

Online sequential extreme learning machine (OS-ELM) is one of the most popular real-time learning strategy for feedforward neural networks with single hidden layer due to its fast learning speed and excellent generalization ability. When dealing with quaternion signals, traditional real-valued learning models usually provide only suboptimal solutions compared with their quaternion-valued counterparts. However, online sequential quaternion extreme learning machine (OS-QELM) model is still lacking in literature. To fill this gap, this paper aims to establish a framework for the derivation and the design of OS-QELM. Specifically, we first derive a standard OS-QELM, and then propose two augmented OS-QELM models which can capture the complete second-order statistics of noncircular quaternion signals. The corresponding regularized models and two approaches to reducing the computational complexity are also derived and discussed respectively. Benefiting from the quaternion algebra and the augmented structure, the proposed models exhibit superiority over OS-ELM in simulation results on several benchmark quaternion regression problems and colour face recognition problems. [ABSTRACT FROM AUTHOR]

Here, we describe the robust and efficient application of the conventional 3D BEM in solving elasticity problems. We have focused on the precise computation of weakly singular integrals. The conformal Duffy-distance transformation was employed to alleviate near singularities caused from two aspects: (1) the large aspect ratio of elements, i.e., element shape distortions; and (2) the closeness of element boundaries to field points, i.e., ill-shaped patches. Then, the rigid body motion method was employed to evaluate strongly singular integrals. Numerical solutions of 3D elastostatic problems demonstrated the high accuracy of the proposed method with coarse meshes and high convergence rates with mesh refinement. Compared with the Duffy transformation and original polar coordinate transformations, the proposed method is insensitive to element shapes. [ABSTRACT FROM AUTHOR]

Synthetic aperture radar (SAR) is a suitable tool to obtain reliable wind retrievals with high spatial resolution. The geophysical model function (GMF), which is widely employed for wind speed retrieval from SAR data, describes the relationship between the SAR normalized radar cross-section (NRCS) at the copolarization channel (vertical-vertical and horizontal-horizontal) and a wind vector. SAR-measured NRCS at cross-polarization channels (horizontal-vertical and vertical-horizontal) correlates with wind speed. In this study, a semi-empirical algorithm is presented to retrieve wind speed from the noisy Chinese Gaofen-3 (GF-3) SAR data with noise-equivalent sigma zero correction using an empirical function. GF-3 SAR can acquire data in a quad-polarization strip mode, which includes cross-polarization channels. The semi-empirical algorithm is tuned using acquisitions collocated with winds from the European Center for Medium-Range Weather Forecasts. In particular, the proposed algorithm includes the dependences of wind speed and incidence angle on cross-polarized NRCS. The accuracy of SAR-derived wind speed is around 2.10 m s-1 root mean square error, which is validated against measurements from the Advanced Scatterometer onboard the Metop-A/B and the buoys from the National Data Buoy Center of the National Oceanic and Atmospheric Administration. The results obtained by the proposed algorithm considering the incidence angle in a GMF are relatively more accurate than those achieved by other algorithms. This work provides an alternative method to generate operational wind products for GF-3 SAR without relying on ancillary data for wind direction. [ABSTRACT FROM AUTHOR]

The mixer settler is widely employed in the extraction and recycling of battery materials. The improvement of the separation efficiency is one of the most important issues. In order to investigate the effect of agitating speed on the flow characteristics and settling performance, both computational fluid dynamics coupled population balance model simulations and experiments with particle image velocimetry measurement have been performed in this work to investigate the flow field at different agitating speeds. The predicted data were in good agreement with the experimental data. The results demonstrated that an appropriate agitating speed could effectively promote the collision efficiency of organic phase droplets and accelerate the separation process. When the agitating speed was too large, the shear stress of the fluid would promote the breakage of the organic phase droplets and decrease the separation efficiency. This work will contribute to optimizing and designing large-scale stirring settlers. [ABSTRACT FROM AUTHOR]

Mixer-settlers have been widely employed in the rare earth element separation industry. Presently, reducing the loss of reagents and occupied areas and achieving a highly efficient separation in the settler are challenging issues. In this work, we report numerical simulations of the liquid–liquid flow in a stirring settler and thereafter describe the experimental validation. A computational fluid dynamics coupled population balance model (CFD-PBM) was developed to investigate the liquid–liquid flow characteristics and settling performance. The dispersion band thickness predicted by the turbulent aggregation model was in good agreement with the experimental measurements. The effects of the total liquid flow rate and initial average droplet diameter on the settling characteristics were further investigated. It was found that the dispersion band thickness increased significantly as the droplet diameter decreased. Moreover, this research shows that the CFD-PBM coupled model is promising for designing large-scale stirring settlers. [ABSTRACT FROM AUTHOR]

Gaofen-3 (GF-3) is the first Chinese space-borne satellite to carry the C-band multi-polarization synthetic aperture radar (SAR). Marine applications, i.e., winds and waves retrieved from GF-3 SAR images, have been operational since January 2017. In this study, we have collected more than 1000 quad-polarization (vertical-vertical (VV); horizontal-horizontal (HH); vertical- horizontal (VH); horizontal-vertical (HV)) GF-3 SAR images, which were acquired around the China Seas from September 2016 to September 2017. Wind streaks were visible in these images in co-polarization (VV and HH) channel. Geophysical model functions (GMFs), including the CMOD5N together with polarization ratio (PR) model and C-SARMOD, were used to retrieve winds from the collected co-polarization GF-3 SAR images. Wind directions were directly obtained from GF-3 SAR images. Then, the SAR-derived wind speeds were compared with the measurements at a 0.25° grid from the Advanced Scatterometer on board the Metop-A/B and microwave radiometer WindSAT. Based on the analysis, empirical corrections are proposed to improve the performance of the two GMFs. Results of this study show that the standard deviation of wind speed is 1.63 m s−1 with a 0.19 m s−1 bias and 1.71 m s−1 with a 0.26 m s−1 bias for VV- and HH-polarization GF-3 SAR, respectively. Our work not only systematically evaluates wind retrieval by using the two advanced GMFs and PR models but also proposes empirical corrections to improve the accuracy of wind retrievals from GF-3 SAR images around the China Seas and thus enhance the accuracy of near real-time operational SAR-derived wind products. [ABSTRACT FROM AUTHOR]

This paper investigates a novel parallel technique based on the spectral deferred correction (SDC) method and a compensation step for solving first-order evolution problems, and we call it para-SDC method for convenience. The standard SDC method is used in parallel with a rough initial guess and a Picard integral equation with high precision initial condition is acted as a compensator. The goal of this paper is to show how these processes can be parallelized and how to improve the efficiency. During the SDC step an implicit or semi-implicit method can be used for stiff problems which is always time-consuming, therefore that’s why we do this procedure in parallel. Due to a better initial condition of parallel intervals after the SDC step, the goal of compensation step is to get a better approximation and also avoid of solving an implicit problem again. During the compensation step an explicit Picard scheme is taken based on the numerical integration with polynomial interpolation on Gauss Radau II nodes, which is almost no time consumption, obviously, that’s why we do this procedure in serial. The convergency analysis and the parallel efficiency of our method are also discussed. Several numerical experiments and an application for simulation Allen-Cahn equation are presented to show the accuracy, stability, convergence order and efficiency features of para-SDC method. [ABSTRACT FROM AUTHOR]

Chinese Gaofen-3 (GF-3) is the first civilian satellite to carry C-band (5.3 GHz) synthetic aperture radar (SAR). During the period of August 2016 to December 2017, 1 523 GF-3 SAR images acquired in quad-polarization (vertical-vertical (VV), horizontal-horizontal (HH), vertical-horizontal (VH), and horizontal-vertical (HV)) mode were recorded, mostly around China’s seas. In our previous study, the root mean square error (RMSE) of significant wave height (SWH) was found to be around 0.58 m when compared with retrieval results from a few GF-3 SAR images in co-polarization (VV and HH) with moored measurements by using an empirical algorithm CSAR_WAVE. We collected a number of sub-scenes from these 1 523 images in the co-polarization channel, which were collocated with wind and SWH data from the European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis field at a 0.125° grid. Through the collected dataset, an improved empirical wave retrieval algorithm for GF-3 SAR in co-polarization was tuned, herein denoted as CSAR_WAVE2. An additional 92 GF-3 SAR images were implemented in order to validate CSAR_WAVE2 against SWH from altimeter Jason-2, showing an about 0.52 m RMSE of SWH for co-polarization GF-3 SAR. Therefore, we conclude that the proposed empirical algorithm has a good performance for wave retrieval from GF-3 SAR images in co-polarization. [ABSTRACT FROM AUTHOR]

Diamond-Blackfan anemia (DBA) is an inherited bone marrow failure syndrome characterized by a paucity of erythroid progenitors. We summarized the clinical and genetic features of 104 DBA patients in a single-center retrospective study in China. Data of DBA patients who received consultations at our center from 2003 to 2015 were analyzed retrospectively. Genes encoding 10 ribosomal proteins (RPs) and GATA1 were sequenced for mutation detection. Our cohort was composed of 65 males and 39 females. Congenital malformations were observed in 19 patients. Mutations of the RP genes were detected in 58.3 % patients. Twenty different mutations were first reported. Thirty-four patients received prednisone combined with CsA therapy, and improvement was observed in 20 cases. During follow-up for a median 39 months, 33.7 % of the patients achieved remission, 41.3 % of the patients were persistently transfusion independent, 21.7 % of the patients were transfusion dependent, and three patients died. The patient group with detected mutations had a younger age of disease onset, a higher malformation rate, and tended to have a lower remission rate and a higher transfusion-dependence rate. Prednisone in combination with cyclosporine A can be a second-line choice for DBA patients. Differences were detected between DBA patients with and without detectable mutations in the genes studied. [ABSTRACT FROM AUTHOR]

Temperature rise is a significant factor influencing microstructure during (α + β) deformation of TA15 titanium alloy. An experiment was designed to explore microstructure evolution induced by temperature rise due to deformation heat. The experiment was carried out in (α + β) phase field at typical temperature rise rates. The microstructures of the alloy under different temperature rise rates were observed by scanning electron microscopy (SEM). It is found that the dissolution rate of primary equiaxed α phase increases with the increase in both temperature and temperature rise rate. In the same temperature range, the higher the temperature rise rate is, the larger the final content and grain size of primary equiaxed α phase are due to less dissolution time. To quantitatively depict the evolution behavior of primary equiaxed α phase under any temperature rise rates, the dissolution kinetics of primary equiaxed α phase were well described by a diffusion model. The model predictions, including content and grain size of primary equiaxed α phase, are in good agreement with experimental observations. The work provides an important basis for the prediction and control of microstructure during hot working of titanium alloy. [ABSTRACT FROM AUTHOR]

Short-chain chlorinated paraffins (SCCPs) are highly complex technical mixtures with thousands of isomers and numerous homologs. They are classified as priority candidate persistent organic pollutants under the Stockholm Convention for their persistence, bioaccumulation, and toxicity. Analyzing SCCPs is challenging because of the complexity of the mixtures. Chromatograms of SCCPs acquired using one-dimensional (1D) gas chromatography (GC) contain a large characteristic “peak” with a broad and unresolved profile. Comprehensive two-dimensional GC (GC×GC) shows excellent potential for separating complex mixtures. In this study, GC×GC coupled with micro electron capture detection (μECD) was used to separate and screen SCCPs. The chromatographic parameters, including the GC column types, oven temperature program, and modulation period, were systematically optimized. The SCCP congeners were separated into groups using a DM-1 column connected to a BPX-50 column. The SCCP congeners in technical mixtures were separated according to the number of chlorine substituents for a given carbon chain length and according to the number of carbon atoms plus chlorine atoms for different carbon chain lengths. A fish tissue sample was analyzed to illustrate the feasibility of the GC×GC–μECD method in analyzing biological samples. Over 1,500 compounds were identified in the fish extract, significantly more than were identified using 1D GC. The detection limits for five selected SCCP congeners were between 1 and 5 pg/L using the GC×GC method, and these were significantly lower than those achieved using 1D GC. This method is a good choice for analysis of SCCPs in environmental samples, exhibiting good separation and good sensitivity. [ABSTRACT FROM AUTHOR]

It is always a bottleneck to design an effective algorithm for linear time-varying systems in engineering applications. For a class of systems, whose coefficients matrix is based on time-varying polynomial, a modified highly precise direct integration (VHPD-T method) was presented. Through introducing new variables and expanding dimensions, the system can be transformed into a time-invariant system, in which the transfer matrix can be computed for once and used forever with a highly precise direct integration method. The method attains higher precision than the common methods (e.g. RK4 and power series) and high efficiency in computation. Some numerical examples demonstrate the validity and efficiency of the method proposed. [ABSTRACT FROM AUTHOR]

Radial-axial ring rolling process is an irreplaceable metal forming technology for manufacturing various seamless rings. However, during the process, there exists complex interaction of deformations in the radial and axial directions of the ring, so the coordinate deformation between radial and axial directions has crucial influences on the quality of the rolled ring. In this paper, a reliable FE model based on in-process control for the radial-axial ring rolling process has been established under the ABAQUS/Explicit platform. In this model, the motions of the rolls are real-time controlled based on in-process measurement. Then, taking the ratio of axial to radial feed amount as the key parameter, we explored the effects of the coordinate deformation between radial and axial directions on the radial-axial rolling of sleeve-type rings by FE simulations. It is found that the rational diameter growth rates become fewer for making the sleeve-type ring roundness stay well as the ratio of axial to radial feed amount decreases. The ratio of axial to radial feed amount has slight effects on the precision of the ring diameter when the diameter growth rate is large. With the ratio of axial to radial feed amount increasing, the deformation of the sleeve-type ring becomes more nonuniform, while the temperature distribution becomes more uniform. [ABSTRACT FROM AUTHOR]

The bacterial antibiotic resistome (BAR) is one of the most serious contemporary medical challenges. The BAR problem in drinking water is receiving growing attention. In this study, we focused on the distribution, changes, and health risks of the BAR throughout the drinking water treatment system. We extracted the antibiotic resistance gene (ARG) data from recent publications and analyzed ARG profiles based on diversity, absolute abundance, and relative abundance. The absolute abundance of ARG was found to decrease with water treatment processes and was positively correlated with the abundance of 16S rRNA (r2 = 0.963, p < 0.001), indicating that the reduction of ARG concentration was accompanied by decreasing biomass. Among treatment processes, biofiltration and chlorination were discovered to play important roles in shaping the bacterial antibiotic resistome. Chlorination exhibited positive effects in controlling the diversity of ARG, while biofiltration, especially granular activated carbon filtration, increased the diversity of ARG. Both biofiltration and chlorination altered the structure of the resistome by affecting relative ARG abundance. In addition, we analyzed the mechanism behind the impact of biofiltration and chlorination on the bacterial antibiotic resistome. By intercepting influent ARG-carrying bacteria, biofilters can enrich various ARGs and maintain ARGs in biofilm. Chlorination further selects bacteria co-resistant to chlorine and antibiotics. Finally, we proposed the BAR health risks caused by biofiltration and chlorination in water treatment. To reduce potential BAR risk in drinking water, membrane filtration technology and water boiling are recommended at the point of use. [ABSTRACT FROM AUTHOR]

Atropisomeric biaryl motifs are ubiquitous in chiral catalysts and ligands. Numerous efficient strategies have been developed for the synthesis of axially chiral biaryls. In contrast, the asymmetric construction of o-quinone-aryl atropisomers has yet to be realized. Inspired by the rapid progress of the chemistry of biaryls, here we present our initial investigations about the atroposelective construction of axially chiral arylquinones by a bifunctional chiral phosphoric acid-catalyzed asymmetric conjugate addition and central-to-axial chirality conversion. With o-naphthoquinone as both the electrophile and the oxidant, three types of arylation counterparts, namely 2-naphthylamines, 2-naphthols and indoles, are utilized to assemble a series of atropisomeric scaffolds in good yields and excellent enantioselectivities. This approach not only expands the axially chiral library but also offers a route to a class of potential, chiral biomimetic catalysts. Axially chiral compounds have widespread use in asymmetric catalysis. Here, the authors disclose a highly enantioselective synthesis of axially chiral o-naphthoquinones by chiral phosphoric acid catalysis and central-to-axial chirality conversion. [ABSTRACT FROM AUTHOR]

Passively mode-locked fiber laser serves as an ideal playground for exploring the dynamics of dissipative solitons. Recently, two-dimensional materials have attracted growing interests for their excellent optical properties in the research field of ultrafast optics. Here, we report an observation of soliton molecules in a passively mode-locked fiber laser based on optic evanescent field interaction with tungsten disulfide (WS2), which contributes to the study of multi-soliton complexes. Particularly, the WS2 saturable absorber (SA) is fabricated by optically depositing the few-layer WS2 nanosheets onto microfiber. In the experiment, stable mode-locking operations are realized, which manifest the effective performance of the WS2 SA. Harmonic mode-locking phenomena are also observed, and these separate solitons facilitate the generation of multi-soliton complexes. Furthermore, due to soliton-soliton interaction, wandering particle-like solitons can be bound together to produce soliton molecules and bunch of soliton molecules. These results enrich both the exploration of multi-soliton complexes and potential industrial applications. [ABSTRACT FROM AUTHOR]

Passively mode-locked fiber laser serves as an ideal playground for exploring the dynamics of dissipative solitons. Recently, two-dimensional materials have attracted growing interests for their excellent optical properties in the research field of ultrafast optics. Here, we report an observation of soliton molecules in a passively mode-locked fiber laser based on optic evanescent field interaction with tungsten disulfide (WS2), which contributes to the study of multi-soliton complexes. Particularly, the WS2 saturable absorber (SA) is fabricated by optically depositing the few-layer WS2 nanosheets onto microfiber. In the experiment, stable mode-locking operations are realized, which manifest the effective performance of the WS2 SA. Harmonic mode-locking phenomena are also observed, and these separate solitons facilitate the generation of multi-soliton complexes. Furthermore, due to soliton-soliton interaction, wandering particle-like solitons can be bound together to produce soliton molecules and bunch of soliton molecules. These results enrich both the exploration of multi-soliton complexes and potential industrial applications. [ABSTRACT FROM AUTHOR]

The dynamic assembly of the actin cytoskeleton is vital for Magnaporthe oryzae development and host infection. The actin-related protein MoFim1 is a key factor for organizing the M. oryzae actin cytoskeleton. Currently, how MoFim1 is regulated in M. oryzae to precisely rearrange the actin cytoskeleton is unclear. In this study, we found that MoFim1 associates with the M. oryzae mitogen-activated protein (MAP) kinase Pmk1 to regulate actin assembly. MoFim1 directly interacted with Pmk1, and the phosphorylation level of MoFim1 was decreased in Δpmk1, which led to a change in the subcellular distribution of MoFim1 in the hyphae of Δpmk1. Moreover, the actin cytoskeleton was aberrantly organized at the hyphal tip in the Δpmk1, which was similar to what was observed in the Δmofim1 during hyphal growth. Furthermore, phosphorylation analysis revealed that Pmk1 could phosphorylate MoFim1 at serine 94. Loss of phosphorylation of MoFim1 at serine 94 decreased actin bundling activity. Additionally, the expression of the site mutant of MoFim1 S94D (in which serine 94 was replaced with aspartate to mimic phosphorylation) in Δpmk1 could reverse the defects in actin organization and hyphal growth in Δpmk1. It also partially rescues the formation of appressorium failure in Δpmk1. Taken together, these findings suggest a regulatory mechanism in which Pmk1 phosphorylates MoFim1 to regulate the assembly of the actin cytoskeleton during hyphal development and pathogenesis., (© 2024. The Author(s).)