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The technical challenges associated with deep underground space activities have become increasingly significant. Among these challenges, one major concern is the assessment of rockburst risks and the instability of rock masses. Extensive research has been conducted by numerous scholars to mitigate the risks and prevent occurrences of rockburst through various assessment methods. Rockburst incidents commonly occur during the excavation of hard rock in underground environments, posing severe threats to personnel safety, equipment integrity, and operational continuity. Thus, it is crucial to systematically document real cases of rockburst, allowing for a comprehensive understanding of the underlying mechanisms and triggering conditions. This understanding will contribute to the advancement of rockburst prediction and prevention methods. Proper selection of an appropriate rockburst assessment method is a fundamental aspect in underground operations. However, there is a limited number of studies that summarize and compare different prediction and prevention methods of rockburst. This paper aims to address this gap by analyzing global trends using CiteSpace software since 1990. It discusses rockburst classification and characteristics, comprehensively reviews research findings related to rockburst prediction, including empirical, simulation, mathematical modeling, and microseismic monitoring methods. Additionally, the paper presents a compilation of current rockburst prevention measures. Notably, the paper emphasizes the significance of control strategies, which provide key insights into the effective utilization of stored energy within rock. Finally, the paper concludes by suggesting six directions for implementing intelligent management techniques to mitigate hazards during underground operations and reduce the probability of rockburst incidents. [ABSTRACT FROM AUTHOR]

Mammalian fertilization is a species-selective event that involves a series of interactions between sperm proteins and the oocyte's zona pellucida (ZP) glycoproteins. Bovine ZP consists of three glycoproteins: bZP2, bZP3, and bZP4. In our previous study, we demonstrated that bovine sperm binds to plastic wells coated with recombinant bZP4 and identified that the N-terminal domain and the middle region of bZP4 are critical for sperm-binding activity. Here, we investigated the sperm-binding site in the middle region (residues 290 to 340) of bZP4, which includes the hinge region. We showed that bovine sperm binds to bZP4's middle region in a species-selective manner. We mapped the function of bZP4's middle region to its N-glycosylation site at Asn-314 using several recombinant mutated proteins. Moreover, we showed that mutations of the N-glycosylation sites at Asn-314 close to the hinge region and Asn-146 of the hinge region of bZP4 and bZP3, respectively, reduced the sperm-binding activity of the complex of the bZP3 (from 32 to 178) and bZP4 (from 136 to 464) fragments. Together, these results suggest that ZP's middle regions of bZP3 and bZP4 form one of the sperm-binding sites of bovine ZP. [ABSTRACT FROM AUTHOR]

Recent studies have suggested that the human germline mutation rate and spectrum evolve rapidly. Variation in generation time has been linked to these changes, though its contribution remains unclear. We develop a framework to characterize temporal changes in polymorphisms within and between populations, while controlling for the effects of natural selection and biased gene conversion. Application to the 1000 Genomes Project dataset reveals multiple independent changes that arose after the split of continental groups, including a previously reported, transient elevation in TCC>TTC mutations in Europeans and novel signals of divergence in C>Gand T>A mutation rates among population samples. We also find a significant difference between groups sampled in and outside of Africa in old T>C polymorphisms that predate the out-of- Africa migration. This surprising signal is driven by TpG>CpG mutations and stems in part from mis-polarized CpG transitions, which are more likely to undergo recurrent mutations. Finally, by relating the mutation spectrum of polymorphisms to parental age effects on de novo mutations, we show that plausible changes in the generation time cannot explain the patterns observed for different mutation types jointly. Thus, other factors - genetic modifiers or environmental exposures - must have had a non-negligible impact on the human mutation landscape. [ABSTRACT FROM AUTHOR]

Background: To investigate effect of microRNA-325-3p (miR-325-3p) on bone metastasis of colorectal cancer (CRC) and the precise role on osteoclastogenesis. Methods: CT-26 cells were injected into tibias to establish bone metastatic model of CRC in vivo. AgomiR-325-3p or antagomir-325-3p were injected in tail-veins of Balb/c mice to interfere the osteoclastogenesis and bone metastasis of CRC. Safranin O and Fast Green staining examined the changes of trabecular area and TRAP staining examined the osteoclast number in bone metastasis of CRC. Real-time PCR was conducted to test the RNA level of miR-325-3p and mRNA levels of TRAP and Cathepsin K in osteoclast precursors (OCPs). Dual-luciferase reporter system was utilized to identify the direct target of miR-325-3p. Conditioned medium from CT-26 cells was collected to stimulate the OCPs during osteoclastogenesis induced by RANKL and M-CSF in vitro. Western blot analysis was performed to examine the protein level of S100A4 in OCPs after interfered by agomiR-325-3p or antagomir-325-3p cultured in CM or not. Results: miR-325-3p downregulated in OCPs in CRC microenvironment both in vivo and in vitro. By luciferase activity assay, S100A4 was the target gene of miR-325-3p and the protein level of S100A4 in OCPs upregulated in CRC microenvironment. Overexpression of miR-325-3p inhibited the osteoclastogenesis of OCPs and it can be reversed after transfection with plasmid containing S100A4. Treatment with miR-325-3p can preserve trabecular area in bone metastasis of CRC. Conclusion: miR-325-3p can prevent osteoclast formation through targeting S100A4 in OCPs. Overexpression of miR-325-3p efficiently decreased the osteoclast number and attenuated bone resorption in bone metastasis of CRC. [ABSTRACT FROM AUTHOR]

The development of launch vehicles has led to higher slenderness ratios and higher structural efficiencies, and the traditional control methods have difficulty in meeting high-quality control requirements. In this paper, an incremental dynamic inversion control method based on deformation reconstruction is proposed to achieve high-precision attitude control of slender launch vehicles. First, the deformation parameters of a flexible rocket are obtained via fiber Bragg grating (FBG) sensors. The deformation and attitude information is introduced into the incremental dynamic inverse control loop, and an attitude control framework that can alleviate bending vibration and deformation is established. The simulation results showed that the proposed method could accurately reconstruct the shapes of flexible launch vehicles with severe vibration and deformation, which could improve the accuracy and stability of attitude control. [ABSTRACT FROM AUTHOR]

Diffusive gradients in thin films (DGT) technology has been increasingly proved to be a promising tool for accurately predicting plant-available phosphorus (P) in soil using air-dried samples. However, the effects of the air-drying process on DGT-measured P are unknown compared to those of using moist samples in which plant roots survive throughout a growing season. We investigated the differences between the Olsen P and DGT P values in 58 air-dried and moist soil samples. The results showed that the discrepancy in the DGT P values between air-dried and moist samples increased with an increase in the organic P concentration in soils. It was presumed that the air-drying process converted some easily mineralized organic P into its inorganic form, thereby allowing it to be measured by the DGT method. The DGT P values in moist samples can be calculated from the values obtained in air-dried samples using the following equation:. However, the Olsen P values were highly correlated (R2 = 0.95) when using air-dried and moist samples, although significant differences were observed. We concluded that the effects of air-drying on predicting soil available P using the Olsen P method can be neglected due to the high correlation relationship. The availability of easily mineralized organic P needs to be further explored. [ABSTRACT FROM AUTHOR]

In traditional Chinese medicine (TCM) theory, pathogenic heat and toxins, which are akin to the inflammatory factors, are the causes of cancer and could promote its virulent development. Therefore, heat-clearing and detoxicating (HCD) herbs are essential components of TCM formulas for cancer treatment. An increasing interest has been focused on the study of HCD herbs and accumulated evidences have shown that HCD herbs or HCD herbs-based formulas exhibited remarkable anticancer effects when used alone or combined with other therapeutic approaches. Some of the HCD herb-derived products have been tested in clinical trials. Studies revealed that extracts or pure compounds of the HCD herbs showed a broad anticancer spectrum against both solid and hematologic malignancies without significant toxic effects. Notably, some HCD herbs or formulas could strongly enhance the anticancer activities of chemo- or radio-therapy and alleviate their side effects. The anticancer activities of HCD herb exacts or the pure compounds were reported to be through multiple cellular or molecular mechanisms, such as induction of cancer cell apoptosis, differentiation and cell cycle arrest, inhibition of cancer cell growth, invasion and metastasis, and inhibition of tumor angiogenesis. In this review, we provide comprehensive analysis and summary of research progress and future prospects in this field to facilitate the further study and application of HCD herbs. [ABSTRACT FROM AUTHOR]

BACKGROUND: There are limited data describing the functional status (FS) of children after heart transplant (HT). We sought to describe the FS of children surviving at least 1 year after HT, to evaluate the impact of HT on FS, and to identify factors associated with abnormal FS post-HT. METHODS: Organ Procurement and Transplantation Network data were used to identify all US children <21 years of age surviving ≥1 year post-HT from 2005 to 2014 with a functional status score (FSS) available at 3 time points (listing, transplant, ≥1 year post-HT). Logistic regression and generalized estimating equations were used to identify factors associated with abnormal FS (FSS≤8) post-HT. RESULTS: A total of 1633 children met study criteria. At the 1-year assessment, 64% were "fully active/no limitations" (FSS=10), 21% had "minor limitations with strenuous activity" (FSS=9); and 15% scored ≤8. In comparison with listing FS, FS at 1 year post-HT increased in 91% and declined/remained unchanged in 9%. A stepwise regression procedure selected the following variables for association with abnormal FS at 1 year post-HT: ≥18 years of age (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.2-2.7), black race (OR, 1.5; 95% CI, 1.1-2.0), support with ≥inotropes at HT (OR, 1.7; 95% CI, 1.2-2.5), hospitalization status at HT (OR, 1.5; 95% CI, 1.0-2.19), chronic steroid use at HT (OR, 1.5; 95% CI, 1.0-2.2), and treatment for early rejection (OR, 2.0; 95% CI, 1.5-2.7). CONCLUSION: Among US children who survive at least 1 year after HT, FS is excellent for the majority of patients. HT is associated with substantial improvement in FS for most children. Early rejection, older age, black race, chronic steroid use, hemodynamic support at HT, and being hospitalized at HT are associated with abnormal FS post-HT. [ABSTRACT FROM AUTHOR]

The WS2 nanosheet, a two-dimensional layered nanomaterial, shows high fluorescence quenching ability for the dye-labeled ssDNA. Currently, most of the fluorescent DNA detection methods employ DNA as a probe for recognition of target DNA. Peptide nucleic acid (PNA) is a D N A mimic but a neutral molecule, showing superior hybridization properties to target DNA. Based on the unique properties of WS2 nanosheet and PNA-DNA hybridization, we have developed a rapid, simple, stable and sensitive approach for DNA detection based on good fluorescence quenching ability of the WS2 nanosheet as well as high binding affinity and specificity of PNA to DNA. This novel assay is capable of exhibiting high sensitivity and specificity with a detection limit of 500 pM, and discriminating between single bases. [ABSTRACT FROM AUTHOR]

We found seroprevalences for hepatitis E virus (HEV) of 7.5%, 18.5%, and 83.3% in specific pathogen-free (SPF) laboratory rabbits, monkeys, and pigs, respectively, in China. HEV RNA was detected in 4.8% of SPF rabbits, and 11 rabbits had latent infections. Screening for HEV in SPF animals before relevant experiments are conducted is recommended. [ABSTRACT FROM AUTHOR]

Intelligent traffic control is an important issue of the modern transportation system. However, in large-scale urban transportation systems, traditional centralized coordination methods suffer bottlenecks in both communication and computation. Decentralized control is hard if there is very limited observation to the whole network as evidences to support joint traffic coordination decisions. In this paper, we proposed a novel decentralized, multiagent based approach for massive traffic lights coordination to promote the large-scale green transportation. Considering that only the traffic from the adjacent intersections may affect the state of a given intersection one time ahead, the key of our approach is using the observations of a local intersection and its neighbors as evidences to support the traffic light coordination decisions. Therefore, we can model the interactions as decentralized agents coordinating with a decision theoretical model. Within a local intersection, constraint optimizing agents are designed to efficiently search for joint activities of the lights. Since this approach involves only local intersection cooperation, it is well scalable and easily implemented with small communication overhead. In the last section, we present our software design on this approach and based on our simulation, this approach is feasible to a large urban transportation system. [ABSTRACT FROM AUTHOR]

Abstract: Pure gravity orbit is an orbit removed non-gravity disturbances, which can give a more precise relation between gravity and orbit, and can be used to navigation satellite, earth gravity felid measurement, gravity wave detection and other fundamental physical test mission. In this paper, the author propose a system concept of a new pure gravity orbit acquirement method named inner formation flying system, which treats the PM and the outer satellite as a pair of formation flying satellites. The inner formation flying system consists of an outer satellite and an inner satellite. The outer satellite is a small satellite with a cavity in the center. The inner satellite is a PM flying in the housing of the outer satellite''s cavity. So the inner satellite is shielded from non-gravitational forces of atmosphere drag and radiation pressure and flies along a purely gravitational path. From the view of formation flying, the outer satellite can be treated as a formation satellite with zero or small distance to the inner reference satellite. So the analysis of mechanic and dynamics of inner formation is made at first. Then a control architecture including feed forward and feedback strategies is presented and the controller is designed. The simulation is carried out in a high precision formation flying simulation environment at last to validate the inner formation flying methods. [Copyright &y& Elsevier]

We consider a single-machine scheduling problem with upper bounded actual processing time and upper bounded maintenance time under deteriorating effect. The actual processing time of a job is a position-dependent power function. If the actual processing time of a job exceeds the upper bound, tardiness penalty of the job should be paid. And if the maintenance time exceeds the corresponding upper bound, tardiness penalty of the maintenance should also be paid. The maintenance duration studied in the paper is a position-dependent exponential function. The objective is to find jointly the optimal maintenance frequency and the optimal job sequence to minimize the total cost, which is a linear function of the make span and the total tardiness. We show that the studied scheduling problem can be transformed as a classic assignment problem to solve. There is also shown that a special case of the scheduling problem can be optimally solved by a lower order algorithm. [ABSTRACT FROM AUTHOR]

This paper investigates the scheduling problems with general deterioration models. By the deterioration models, the actual processing time functions of jobs depend not only on the scheduled position in the job sequence but also on the total weighted normal processing times of the jobs already processed. In this paper, the objective is to minimize the makespan. For the singlemachine scheduling problems with general deterioration effects, we show that the considered problems are polynomially solvable. For the flow shop scheduling problems with general deterioration effects, we also show that the problems can be optimally solved in polynomial time under the proposed conditions. [ABSTRACT FROM AUTHOR]

There are various control laws for attitude stabilization and maneuvering such as magnetic torque control, solar torque control, momentum exchange control. Such controllers work in a linear continuous mode. But the torque that they can produce is in the range of 0.02–1 N m for momentum exchange control, 10−2–10−3 N m for magnetic torque control, and 10−5–10−6 N m for solar torque control. Therefore, the speed of attitude maneuvering is limited by the low-level maximal torques that can be delivered to the attitude control system. Thruster control used in attitude control is no linear continuous reaction thrust control. However, they can provide almost any torque level. Their range between 0.01 N m and 30 N m, which is very common in most satellite. It is practical and convenient to use thruster for the rate damping control of small satellite during initial separation from launch vehicle. The paper deals with the analysis and design of thruster attitude control of a small satellite OptimSat. Simulation results shows that rate damping control for small satellite using thruster is effective. [Copyright &y& Elsevier]

In multilayer microwave integrated circuits such as low-temperature co-fired ceramics or multilayered printed circuit boards, waveguide-like structures can be fabricated by using periodic metallic via-holes referred to as substrate integrated waveguide (SIW). Such SIW structures can largely preserve the advantages of conventional rectangular waveguides such as high-Q factor and high power capacity. However, they are subject to leakage due to periodic gaps, which potentially results in wave attenuation. Therefore, such a guided-wave modeling problem becomes a very complicated complex eigen value problem. Since the SIW are bilaterally unbounded, absorbing boundary conditions should be deployed in numerical algorithms. This often leads to a difficult complex root-extracting problem of a transcend equation. In this paper, we present a novel finite-difference frequency-domain algorithm with a perfectly matched layer and Floquet's theorem for the analysis of SIW guided-wave problems. In this scheme, the problem is converted into a generalized matrix eigen value problem and finally transformed to a standard matrix eigen value problem that can be solved with efficient subroutines available. This approach has been validated by experiment. [ABSTRACT FROM AUTHOR]

This paper innovatively proposes six scale-independent relative orbital elements, that can be used for dynamics analysis and control for relative motion with near-circular orbits and arbitrary inter-satellite separation. Scale-independent relative orbital elements are deduced from the first-order decomposed relative motion model. These elements reveal the twisted elliptical characteristics of large-range relative motion and standard elliptical characteristics of close-range relative motion. The error of the proposed relative orbital elements keeps zero for circular orbits and the error is irrelevant to inter-satellite range. Based on the scale-independent relative orbital elements, the configuration design equation is established. Given the configuration requirements, the initial orbital elements of the deputy can be calculated. The autonomous configuration control problem is studied by means of artificial potential functions. Scale-independent relative orbital elements are used as control variables, and the large-range reconfiguration and collision avoidance control are realized with low control consumption. • Six independent configuration parameters are proposed for near-circular and arbitrary separation relative motion. • The configuration design equation for large-range relative motion is formulated. • Reconfiguration and collision avoidance control for large-range distributed space systems are realized autonomously. [ABSTRACT FROM AUTHOR]

The stemness loss-associated dysregeneration of impaired alveolar type 2 epithelial (AT2) cells abolishes the reversible therapy of idiopathic pulmonary fibrosis (IPF). We here report an inhalable mucus-penetrating lipid nanoparticle (LNP) for codelivering dual mRNAs, promoting realveolarization via restoring AT2 stemness for IPF treatment. Inhalable LNPs were first formulated with dipalmitoylphosphatidylcholine and our in-house-made ionizable lipids for high-efficiency pulmonary mucus penetration and codelivery of dual messenger RNAs (mRNAs), encoding cytochrome b5 reductase 3 and bone morphogenetic protein 4, respectively. After being inhaled in a bleomycin model, LNPs reverses the mitochondrial dysfunction through ameliorating nicotinamide adenine dinucleotide biosynthesis, which inhibits the accelerated senescence of AT2 cells. Concurrently, pathological epithelial remodeling and fibroblast activation induced by impaired AT2 cells are terminated, ultimately prompting alveolar regeneration. Our data demonstrated that the mRNA-LNP system exhibited high protein expression in lung epithelial cells, which markedly extricated the alveolar collapse and prolonged the survival of fibrosis mice, providing a clinically viable strategy against IPF. [ABSTRACT FROM AUTHOR]

This paper proposes a novel electromagnetic separation system for the small spherical satellite Q-SAT, which is developed by Tsinghua University. Q-SAT was successfully launched on August 6, 2020 and works well now. Q-SAT requires the separation system no pollution, no impact, multi-point synchronous release and repeatable test. In order to meet these requirements, an electromagnetic separation method is proposed and the system is designed. The system consists of bearing structure, a pair of locking and release mechanism, four ejection mechanism and a drive power. The scheme of separation system can be summarized as "two locks, four ejections". The key to system is the lock and release mechanism using ball-lock principle driven by electromagnets. The analytical relationship of the mechanism driving force is given. How to balance the contradiction between lock and release, which is a problem bring by the system, is discussed. The prototype is made. The verification tests are fully carried out including function, vibration, shock, coldness and velocity measurement. The test results show that the system satisfies the launching requirement. The reliability of the system was proven by the successful separation. Systems based on the same electromagnetic separation method could be widely used on other satellites or payloads in the future. • A novel separation method for a small satellite based on electromagnetic mechanism is proposed. • An electromagnetic separation system is developed for the small spherical satellite Q-SAT based on the method. • The separation system has the characteristics of no impact, no pollution, low cost, repeatable test on the ground and high synchronization. • The separation system is fully verified by test and flight. [ABSTRACT FROM AUTHOR]

A high energy-efficiency capacitor switching scheme for successive approximation register (SAR) analogue-to-digital converters (ADCs) is presented. The switching method, verified on a 10-bit SAR scheme that uses bottom plate sampling, achieves an average switching energy and area reduction of 99.32 and 96.5%, respectively, with respect to the conventional solution. [ABSTRACT FROM AUTHOR]

Explore the nursing effect of patients with polyangitis under microscope, and to formulate and analyze the nursing intervention methods. From June 2016 to June 2019, 60 patients with polyangitis under microscope were selected as the research objects. According to the sequence of admission, they were divided into observation group and control group, 30 cases in each group. The control group received routine nursing; the observation group received comprehensive nursing intervention. The five factor scores (FFS) and Birmingham vasculitis activity score (BVAS) before and after nursing were compared between the two groups. The tissue and organ involvement, including skin, eye, lung, otolaryngology, kidney and Guanjie, laboratory C-reactive protein, blood creatinine and hemoglobin, and patient satisfaction were observed. After nursing intervention, the scores of FFS and BVAS in the two groups were significantly lower than those in the control group, with a statistically significant difference (P<0.05); before nursing intervention, there was no significant difference between the two groups (P>0.05). After comprehensive nursing intervention, the scores of FFS and BVAS in the observation group were lower than those in the control group, the difference was statistically significant (P<0.05). Compared with the control group, the incidence of tissue and organ involvement in the observation group was significantly lower, with a statistically significant difference (P<0.05); Compared with the control group, the laboratory indexes C reactive protein, serum creatinine and hemoglobin were significantly decreased in the observation group, with a statistically significant difference (P<0.05); Compared with the control group, the patient satisfaction of the observation group was significantly improved, and the difference was statistically significant (P<0.05). It can be used to evaluate and analyze the effects of nursing interventions. The comprehensive nursing intervention under the microscope can effectively alleviate the symptoms of vasculitis, reduce the incidence of tissue and organ involvement, control infection, enhance the treatment effect, and improve patient satisfaction. [ABSTRACT FROM AUTHOR]

With the development of satellite cluster and giant constellations in recent years, the orbit design and long-term maintenance of these systems become more difficult with the restriction of fuel consumption and the influence of orbital perturbations. It's necessary to study the analytical model of relative motion which applicable to different inter-satellite ranges. Then, considering the perturbed evolutions of orbital elements, the decomposed relative motion model was proposed by separating the higher-fidelity relative motion model into two different parts, which reflect the circling motion around chief, and their overall motion relative to chief respectively. Eccentricity expansions had been carried out to provide a time-explicit analytical solution of the decomposed model. Based on this first order time-explicit analytical solution, the bound relative motions with different inter-satellite ranges were studied in Kepler orbit. The initial condition calculation formula for general chief centered circular relative motion was derived at the same time. The accuracy of first order analytical solution of the decomposed model was estimated both theoretically and numerically, to show the effect of inter-satellite range and chief's eccentricity. At last, the first order analytical solution using mean orbital elements was compared with high precision numerical solution under perturbations to validate it's effective in long-term stability analysis. • Decomposed relative motion model was proposed using classical orbital elements. • Analytical solution of decomposed model was provided without distance limitation. • Initial condition formula for general chief centered circular motion was derived. • Theoretical accuracy estimation equation directly reflects the key effect factors. • Simulations validate the effectiveness of analytical solution under perturbations. [ABSTRACT FROM AUTHOR]

An intelligent, person-following nanosatellite is under development for in-cabin astronaut assistance in the China Space Station. It is named the Intelligent Formation Personal Satellite (IFPS). The satellite weighs 2.0 kg and is shaped as a sphere of diameter 230 mm. Fans and MEMS flywheels are used for its position and attitude maneuvering as inside the Space Station cabin it is a weightless and standard atmospheric pressure environment. The RGB-D camera and IMU based visual-inertial SLAM method is used to support its localization and navigation. The on-board information processing and computing hardware primarily consists of an embedded AI microprocessor and an FPGA. The satellite is designed to fly autonomously and follow the designated astronaut to offer immediate assistance. Thus, efficient and robust astronaut visual tracking is the most important prerequisite for supporting its basic person-following operating mode. We achieved this by further improving our previously proposed tracking algorithm that consists of a deep convolution neural network (DCNN)-based detection module and a probabilistic-model-based tracking module. The DCNN in the detection module was further improved through optimizations of lightweight network architecture design, parameters model compression and inference acceleration. While maintaining the originally high detection accuracy, the DCNN was optimized significantly in terms of memory, computation and power consumption to quite meet the engineering constraints in the development of IFPS. The complete pipeline of the astronaut visual tracking algorithm was also designed and implemented in the embedded AI microprocessor for online tracking application. Experimental results demonstrated the effectiveness of the proposed efficient and robust astronaut detection and tracking algorithm. • An in-cabin nanosatellite for astronaut assistance is designed. Deep-learning-based astronaut visual tracking algorithm is proposed for supporting its astronaut-following operating mode. • An efficient DCNN was developed through lightweight network architecture design, parameters model compression and inference acceleration. • The DCNN provides high detection accuracy, and its memory requirements, computation burden and power consumption are engineering affordable. • The deep-learning-based tracking algorithm runs efficiently on embedded hardware. Robust detection and tracking performance is verified by experiments. [ABSTRACT FROM AUTHOR]

Antibiotic resistance is a major global health crisis facing humanity, with horizontal gene transfer (HGT) as a principal dissemination mechanism in the natural and clinical environments. Perfluoroalkyl substances (PFASs) are emerging contaminants of global concern due to their high persistence in the environment and adverse effec ts on humans. However, it is unknown whether PFASs affect the HGT of bacterial antibiotic resistance. Using a genetically engineered Escherichia coli MG1655 as the donor of plasmid-encoded antibiotic resistance genes (ARGs), E. coli J53 and soil bacterial community as two different recipients, this study demonstrated that the conjugation frequency of ARGs between two E. coli strains was (1.45 ± 0.17) × 10-5 and perfluorooctane sulfonate (PFOS) at environmentally relevant concentrations (2-50 μg L-1) increased conjugation transfer between E. coli strains by up to 3.25-fold. Increases in reactive oxygen species production, cell membrane permeability, biofilm formation capacity, and cell contact in two E. coli strains were proposed as major promotion mechanisms from PFOS exposure. Weighted gene co-expression network analysis of transcriptome data identified a series of candidate genes whose expression changes could contribute to the increase in conjugation transfer induced by PFOS. Furthermore, PFOS also generally increased the ARG transfer into the studied soil bacterial community, although the uptake ability of different community members of the plasmid either increased or decreased upon PFOS exposure depending on specific bacterial taxa. Overall, this study reveals an unrecognized risk of PFOS in accelerating the dissemination of antibiotic resistance. Perfluoroalkyl substances (PFASs) are emerging contaminants of global concern due to their high persistence in the environment and adverse health effects. Although the influence of environmental pollutants on the spread of antibiotic resistance, one of the biggest threats to global health, has attracted increasing attention in recent years, it is unknown whether environmental residues of PFASs affect the dissemination of bacterial antibiotic resistance. Considering PFASs, often called "forever" compounds, have significantly higher environmental persistence than most emerging organic contaminants, exploring the effect of PFASs on the spread of antibiotic resistance is more environmentally relevant and has essential ecological and health significance. By systematically examining the influence of perfluorooctane sulfonate on the antibiotic resistance gene conjugative transfer, not only at the single-strain level but also at the community level, this study has uncovered an unrecognized risk of PFASs in promoting conjugative transfers of bacterial antibiotic resistance genes, which could be incorporated into the risk assessment framework of PFASs. [ABSTRACT FROM AUTHOR]

Estimating cadmium (Cd) bioavailability and transfer to plants are important for food safety. We aimed to determine the dominant soil factors regulating the transfer of Cd from a wide variety of Chinese soils to Pak Choi (Brassica chinensis) and to establish a model for prediction of Cd uptake in B. chinensis. A greenhouse experiment was conducted in which B. chinensis plants were grown under 14-h 20±C light/10-h 16±C dark photoperiod for 60 d. The total Cd content in the plant and soil samples was measured. The Cd concentration in B. chinensis was positively correlated to the soil Cd concentration, and negatively correlated to the soil pH and soil organic carbon (SOC) content. The bio-concentration factors (BCF) measured in acidic soils (the maximum value being 0.551) were higher than those in alkaline soils (the maximum value being 0.366). Multivariable (pH, SOC, and total soil Cd) regression analysis could estimate the Cd bioavailability more accurately compared with the single-factor (total soil Cd) analysis. The most accurate Freundlich-type equation (Log[Cplant] = 2.34Log[Csoil] - 0.27pH - 0.23Log[SOC] + 0.92) was developed to estimate the Cd bioavailability using combined data from all treatments. The model described by us would be useful for estimating the bioavailability of Cd to B. chinensis in a variety of soils and would be helpful in assessing the risk of Cd contamination in soils. [ABSTRACT FROM AUTHOR]

Q-SAT, a small spherical satellite designed and developed by Tsinghua university, was successfully launched on Aug 6, 2020 at Jiuquan satellite launch center in China. The mission of Q-Sat is the joint measurement of long-wavelength Earth gravity field and upper atmosphere density, which is of great significance for improving spacecraft orbit prediction and promoting the development of satellite gravity measurement technology. The satellite is designed in spherical shape innovatively and deploys high dynamic dual-frequency GPS as the main payload. On-orbit data shows that the atmospheric density detection precision is in the order of 10−14kg/m3 and the gravity recovery precision achieves the level of 30 orders. All mission success criteria and objectives were achieved. This paper presents the design, space mission, key technologies, science capabilities and preliminary results of the satellite. • Q-SAT, a spherical satellite for the joint measurement of long-wavelength Earth gravity field and upper atmosphere density, was launched in 2020. • An electromagnetic separation system with point connection-release structure is designed for the Q-Sat. • As secondary payload a powerful GPU module is implemented to validate artificial intelligence computing capabilities in orbit. • Modifications for the Jacchia-Roberts atmospheric density model are proposed in the paper. [ABSTRACT FROM AUTHOR]

The genus Vibrio is characterized by high metabolic flexibility and genome plasticity and is widely distributed in the ocean from euphotic layers to deep-sea environments. The relationship between genome features and environmental adaptation strategies of Vibrio has been extensively investigated in coastal environments, yet very little is known about their survival strategies in oligotrophic deep-sea. In this study, we compared genomes of five Vibrio campbellii strains isolated from the Mariana and Yap Trenches at different water depths, including two epipelagic strains and three hadopelagic strains, to identify genomic characteristics that facilitate survival in the deep sea. Genome streamlining is found in pelagic strains, such as smaller genome sizes, lower G1C contents, and higher gene densities, which might be caused by long-term residence in an oligotrophic environment. Phylogenetic results showed that these five Vibrio strains are clustered into two clades according to their collection depth. Indeed, hadopelagic isolates harbor more genes involved in amino acid metabolism and transport, cell wall/membrane/envelope biogenesis, and inorganic ion transport and metabolism through comparative genomics analysis. Specific macrolide export gene and more tellurite resistance genes present in hadopelagic strains by the annotation of antibiotic and metal resistance genes. In addition, several genes related to substrate degradation are enriched in hadopelagic strains, such as chitinase genes, neopullulanase genes, and biopolymer transporter genes. In contrast, epipelagic strains are unique in their capacity for assimilatory nitrate reduction. The genomic characteristics investigated here provide insights into how Vibrio adapts to the deep-sea environment through genomic evolution. [ABSTRACT FROM AUTHOR]

There is an increasing demand for automatic online detection system and computer vision plays a prominent role in this growing field. In this paper, the automatic real-time detection system of the clamps based on machine vision is designed. It hardware is composed of a specific light source, a laser sensor, an industrial camera, a computer, and a rejecting mechanism. The camera starts to capture an image of the clamp once triggered by the laser sensor. The image is then sent to the computer for defective judgment and location through gigabit Ethernet (GigE), after which the result will be sent to rejecting mechanism through RS485 and the unqualified ones will be removed. Experiments on real-world images demonstrate that the pulse coupled neural network can extract the defect region and judge defect. It can recognize any defect greater than 10 pixels under the speed of 2.8 clamps per second. Segmentations of various clamp images are implemented with the proposed approach and the experimental results demonstrate its reliability and validity. [ABSTRACT FROM AUTHOR]

fast and sensitive liquid chromatography-mass spectrometry method was developed for the determination of ursolic acid (UA) in rat plasma and tissues. Glycyrrhetinic acid was used as the internal standard (IS). Chromatographic separation was performed on a 3.5 μm Zorbax SB-C18 column (30 mm × 2.1 mm) with a mobile phase consisting of methanol and aqueous 10 mM ammonium acetate using gradient elution. Quantification was performed by selected ion monitoring with ( m/ z) 455 for UA and ( m/ z) 469 for the IS. The method was validated in the concentration range of 2.5 − 1470 ng mL for plasma samples and 20 − 11760 ng g for tissue homogenates. The intra- and inter-day assay of precision in plasma and tissues ranged from 1.6% to 7.1% and 3.7% to 9.0%, respectively, and the intra- and inter-day assay accuracy was 84.2 − 106.9% and 82.1 − 108.1%, respectively. Recoveries in plasma and tissues ranged from 83.2% to 106.2%. The limits of detections were 0.5 ng mL or 4.0 ng g. The recoveries for all samples were >90%, except for liver, which indicated that ursolic acid may metabolize in liver. The main pharmacokinetic parameters obtained were T = 0.42 ± 0.11 h, C = 1.10 ± 0.31 μg mL, AUC = 1.45 ± 0.21 μg h mL and K = 5.64 ± 1.89 h. The concentrations of UA in rat lung, spleen, liver, heart, and cerebellum were studied for the first time. This method is validated and could be applicable to the investigation of the pharmacokinetics and tissue distribution of UA in rats. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

With Yunyan 87 as an experimental material, the effects of different transplanting dates on the growth and development of tobacco plants and the yield and quality of cured tobacco leaves were studied in Lingbao City, Sanmenxia City. With the postponement of transplanting date, the growth period in field was prolonged , and the plant height and leaf area both increased at first and decreased then. TMV, weather fleck and brown spot all showed an incidence and a disease index decreased with the postponement of transplanting date. The total sugar and reducing sugar contents of the cured tobacco leaves from the upper and middle part increased at first and decreased then with the postponement of transplanting date. The main nitrogenous compounds decreased at first and increased then. The economic traits and leaf class were on the decrease [ABSTRACT FROM AUTHOR]

Abstract Electronics installed in modern complex systems, like automotive and aircraft systems, are mainly subjected to mechanical vibrations in applications. The interconnection structure, as the mechanical fixing and electrical interconnection between the electrical device and the printed circuit board, is a key part in electronics. Presently, there are few researching articles on reliability of QFP interconnect structure under random vibration. In this paper, eight specimens of QFP100 with the self-testing real-time circuit have been tested to failure by subjecting to a narrow-band random vibration at its first natural frequency. The charging time of external capacitor in the self-test circuit has been extracted as the monitoring signal. Failure modes of interconnect structure have been analyzed in statistics. Then, the relationship between the monitoring signal and interconnect failure has been investigated. Finally, failure data, conforms to a two-parameter Weibull distribution, has been used to establish the life distribution of interconnect structure. Results show that there are four failure modes and three failure places in interconnect structure under random vibration, which is consistent with simulation results by FEM, and the charging time can characterize the failure and failure process of interconnect structure well. Highlights • QFP package with the self-testing real-time circuit has been tested to failure under narrow-band random vibration. • The charging time of external capacitor in the self-testing circuit has been extracted as the monitoring signal. • The charging time can characterize the failure and failure process of interconnect structure well. [ABSTRACT FROM AUTHOR]

Nickel selenide with the single-phase structure has been widely studied as counterelectrode nanomaterials for dye-sensitized solar cells (DSCs). However, the effect mechanism of the crystalline structure on the electrocatalytic activity is still needed to be explored and analyzed in nickel selenide with hybrid structure. Therefore, NiSe/NiSe2 hybrid nanomaterials are synthesized via a simple solvothermal approach in this work. NiSe/NiSe2 counterelectrodes are constructed by spraying NiSe/NiSe2 hybrid nanomaterials onto fluorine-doped tin oxide glass. The hybrid nanostructure of NiSe/NiSe2 counterelectrodes exhibits the more catalytic active sites, strong charge separation, and transfer ability for the reduction of triiodide owing to the well-controlled crystalline structure of nickel selenide. Therefore, the results from electrochemical measurements prove that the electrocatalytic activity of the optimized NiSe/NiSe2 counterelectrode is higher than that of platinum electrode. As a result, the DSC with the optimized NiSe/NiSe2 counterelectrode yields a remarkable photoelectrical conversion efficiency of 7.78%, which is larger than that of the DSC based on platinum electrode (7.09%). Our research work provides the insight into design and construct of nickel selenide counterelectrodes of DSCs. [ABSTRACT FROM AUTHOR]

Objective: Unusual clinical course Background: Cryptococcus neoformans (C. neoformans) infection is one of the most common opportunistic infections in AIDS patients. C. neoformans usually infects the central nervous system (CNS) and/or lungs with typical clinical manifestation. Case Report: Here, we report the case of a 52-year-old HIV-1-infected man with disseminated cryptococcosis, including subacute meningitis, pulmonary, and cutaneous cryptococcosis, but only skin lesion served as the chief complaint. Moreover, the results of cerebrospinal fluid (CSF) tests and lung computed tomography (CT) scan were atypical. Conclusions: We present the clinical characteristics of this case and discuss the diagnostic procedure, which will likely help clinicians in making a timely definitive diagnosis of this disease. [ABSTRACT FROM AUTHOR]

Objective: Unusual clinical course Background: Diffuse large B-cell lymphoma (DLBCL) accounts for the large majority of AIDS-related non-Hodgkin's lymphoma (NHL). DLBCL usually arises in lymph nodes, presenting as a painless rapid swelling mass in the neck, armpit, or groin. Case Report: Here, we report a case of DLBCL that needed only 3 months to develop a tumor 20×15 cm in diameter in the right groin and even caused scrotum swelling and lower-extremity edema. Furthermore, this case of DLBCL had developed other 3 subcutaneous tumors in the chest wall and their diameters were 16×9 cm, 7×7 cm, and 3×3 cm. A thoracic computed tomography (CT) scan presented with bilateral pleural effusion and the chest wall tumors with rib lesions. Conclusions: It is rare that a DLBCL needed only 3 months to develop a tumor 20×15 cm in diameter and even caused scrotum swelling and unilateral lower-extremity edema due to the large mass located in the right groin. Furthermore, it is extremely rare that this lymphoma infiltrated the chest wall and even resulted in rib lesions. [ABSTRACT FROM AUTHOR]

MoS2 nanomaterial has unique properties, including innate affinity with ss-DNA and quenching ability for fluorescence dyes. Here, we present the development of a simple fluorescence biosensor based on water-soluble MoS2 nanosheets and restriction endonuclease BstUI for methylation analysis of p16 promoter. The biosensing platform exhibited excellent sensitivity in detecting DNA with a linear range of 100 pM~20 nM and a detection limit of 140 pM. More importantly, our method could distinguish as low as 1% difference in methylation level. Compared with previous methylation analysis, our design is both time saving and simple to operate, avoiding the limitations of PCR-based assays without compromising performance. [ABSTRACT FROM AUTHOR]

The article discusses the study on using Platinum (Pt)/Oxide Nanocatalysts in the interfacial oxidation of carbon monoxide (CO) with Hydroxyls. When researchers did an experiment on ferrous oxide (FeO)(111)/Pt inverse model catalyst, they found that the interfacial COads + OHads reaction produces CO2 that occurs facilely at Pt--oxide interface and at low temperatures. Moreover, the work also provides overview on the reaction mechanism.

A new glass-making method was developed to allow the in situ analysis of trace elements and lead isotopes in rock samples. The apparatus used to prepare homogeneous glass samples from silicate rock powder consisted of a small (450 mm3) boron nitride vessel and a high-temperature furnace. The concentrations of trace elements were measured by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and lead isotopic compositions were measured by femtosecond laser ablation multicollector inductively coupled plasma mass spectrometry (fsLA-MC-ICP-MS). The method was evaluated by analyzing glass disks fused from six geochemical reference materials (spanning the compositional range basalt–andesite–rhyolite). The measured 34 trace element contents match the reference values within 15%, and the mean Pb isotopic ratios measured by fsLA-MC-ICP-MS agree with those obtained by solution nebulizer MC-ICP-MS within 2s uncertainty intervals. By using seven Faraday cups operating in static mode we were able to obtain 207Pb/206Pb and 208Pb/206Pb results with improved precisions by a factor of 2–3 compared to those obtained by previous single-collector sector-field ICPMS and LA-MC-ICP-MS. The accuracies of 207Pb/206Pb and 208Pb/206Pb values obtained by fsLA-MC-ICP-MS lie between −0.073% and +0.023%, which are well determined for geological research. Measured 208Pb/204Pb, 207Pb/204Pb and 206Pb/204Pb isotope ratios for the USGS reference RGM-2 (20 μg g−1 total Pb) and BCR-2 (11 μg g−1 total Pb) agree within 0.029% and 0.055% respectively of the preferred values. For GSR-3 (4.27 μg g−1 total Pb), the accuracies of the 208Pb/204Pb, 207Pb/204Pb and 206Pb/204Pb ratios obtained by fsLA-MC-ICP-MS lie between −0.064% and −0.004% with the accepted external precision of ＜0.15% (1RSD), which are better than previous LA-MC-ICP-MS data in terms of quantification limits. We also provide precise Pb isotopic data for the reference materials GSR-2, GSR-3, QLO-1, and RGM-2 obtained by solution nebulizer MC-ICP-MS. Our method is simpler, cheaper and faster to determine trace elements and Pb isotopic ratios in geological samples, while retaining similar levels of accuracy and precision. [ABSTRACT FROM AUTHOR]

Hormetic response is an adaptive mechanism for a cell or organism surviving in an unfavorable environment. It has been an intriguing subject of researches covering a broad range of biological and medical disciplines, in which the underlying significance and molecular mechanisms are under intensive investigation. In the present study, we demonstrated that topoisomerase I inhibitor camptothecin (CPT), a potent anticancer agent, induced an obvious hormetic response in rat pheochromocytoma PC12 cells. Camptothecin inhibited PC12 cell growth at relative high doses as generally acknowledged while stimulated the cell growth by as much as 39% at low doses. Moreover, low doses of CPT protected the cells from hydrogen peroxide (H2O2)-induced cell death. Phosphoinositide 3-kinase (PI3K)/Akt and nuclear factor-E2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathways were reported playing pivotal roles in protecting cells from oxidative stress. We observed that these 2 pathways were upregulated by low doses of CPT, as evidenced by increased levels of phosphorylated PI3K, phosphorylated Akt, phosphorylated mammalian target of rapamycin, Nrf2, and HO-1; and abolishment of the growth-promoting and neuroprotective effects of CPT by LY294002, a PI3K inhibitor. These results suggest that the hormetic and neuroprotective effects of CPT at low doses on PC12 cells were attributable, at least partially, to upregulated PI3K/Akt and Nrf2/HO-1 pathways. [ABSTRACT FROM AUTHOR]

The article describes the case of a 28-year-old male with HIV infection who presented with fever and mild abdominal pain. The patient was suspected as having a liver abscess and empirical antibiotics were administrated. Symptoms of the patient did not improve, hence a percutaneous liver needle biopsy was done. Further metagenomic sequencing detected Aeromonas salmonicida in the liver tissue. Empirical antibiotics were conversed and the patient rapidly recovered.