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BACKGROUND: The unilateral biportal endoscopic (UBE) technique has been widely used in spine surgery. At present, a traditional rigid working channel is available for the UBE system. A metal semicircular canal is located in the working channel. However, due to the metal material of the working channel, arthroscopy and instruments are constrained from moving in UBE surgery. Additionally, an assistant is needed during the procedure to hold the traditional working channel. OBJECTIVE: For simplicity of operation and convenient movement of the arthroscopy and instrument, we describe a new method for establishing operative channels in UBE surgery. METHODS: We retrospectively reviewed 50 patients who underwent unilateral biportal endoscopic discectomy (UBED) from February 2020 to August 2020 via our new method. The Oswestry Disability Index (ODI) and visual analogue scale (VAS) score were measured preoperatively and 1 month, 3 months, 6 months and 12 months postoperatively. Statistical comparisons were made using analysis of covariance and paired t tests. RESULTS: The VAS scores for back pain at the five time points were 5.20 ± 2.57, 1.96 ± 0.95, 1.50 ± 0.84, 1.64 ± 1.08 and 1.18 ± 0.39. The leg pain VAS scores were 7.02 ± 2.25, 2.02 ± 1.27, 1.48 ± 0.89, 1.32 ± 0.79 and 0.88 ± 0.52. The ODI values were 51.08 ± 19.97, 19.62 ± 15.51, 8.26 ± 7.40, and 7.54 ± 6.42 to 3.24 ± 1.10. The postoperative ODIs and VAS scores of low back pain and leg pain were significantly lower than those before surgery, and differences were statistically significant (all p< 0.05). The pressure of the closed outflow was significantly higher than that of the open outflow (37.35 ± 13.11 mm Hg vs. 24.55 ± 12.64 mm Hg p= 0.003). After we tightened the infusion strap to open the outflow, the pressure decreased significantly (26.4 ± 14.08 mm Hg vs. 37.35 ± 13.11 mm Hg p= 0.015). There were 2 cases of complications, including 1 case of postoperative recurrence and 1 case of dural tears. CONCLUSION: This study demonstrates the technical feasibility, safety, and efficacy of modified channel establishment in UBE surgery.

Abstract: A new tertiary amine-thiourea organocatalyst has successfully been developed and applied into the asymmetric Michael addition of pyrazolin-5-one to nitroalkenes. The catalyst system performed well with a low catalyst loading of 5 mol% under mild reaction conditions. A series of synthetically and pharmaceutically useful chiral pyrazolone derivatives was obtained in high yields (up to 95%) with good enantioselectivities (up to 88 % ee).

A growing body of research suggests that short-chain fatty acids (SCFAs), metabolites produced by intestinal symbiotic bacteria that ferment dietary fibers (DFs), play a crucial role in the health status of symbiotes. SCFAs act on a variety of cell types to regulate important biological processes, including host metabolism, intestinal function, and immune function. SCFAs also affect the function and fate of immune cells. This finding provides a new concept in immune metabolism and a better understanding of the regulatory role of SCFAs in the immune system, which impacts the prevention and treatment of disease. The mechanism by which SCFAs induce or regulate the immune response is becoming increasingly clear. This review summarizes the different mechanisms through which SCFAs act in cells. According to the latest research, the regulatory role of SCFAs in the innate immune system, including in NLRP3 inflammasomes, receptors of TLR family members, neutrophils, macrophages, natural killer cells, eosinophils, basophils and innate lymphocyte subsets, is emphasized. The regulatory role of SCFAs in the adaptive immune system, including in T-cell subsets, B cells, and plasma cells, is also highlighted. In addition, we discuss the role that SCFAs play in regulating allergic airway inflammation, colitis, and osteoporosis by influencing the immune system. These findings provide evidence for determining treatment options based on metabolic regulation.

The human placenta is a unique temporary organ with a mysterious immune tolerance. The formation of trophoblast organoids has advanced the study of placental development. HLA-G is uniquely expressed in the extravillous trophoblast (EVT) and has been linked to placental disorders. With older experimental methodologies, the role of HLA-G in trophoblast function beyond immunomodulation is still contested, as is its role during trophoblast differentiation. Organoid models incorporating CRISPR/Cas9 technology were used to examine the role of HLA-G in trophoblast function and differentiation. JEG-3 trophoblast organoids (JEG-3-ORGs) were established that highly expressed trophoblast representative markers and had the capacity to differentiate into EVT. CRISPR/Cas9 based on HLA-G knockout (KO) significantly altered the trophoblast immunomodulatory effect on the cytotoxicity of natural killer cells, as well as the trophoblast regulatory effect on HUVEC angiogenesis, but had no effect on the proliferation and invasion of JEG-3 cells and the formation of TB-ORGs. RNA-sequencing analysis further demonstrated that JEG-3 KO cells followed similar biological pathways as their wild-type counterparts during the formation of TB-ORGs. In addition, neither HLA-G KO nor the exogenous addition of HLA-G protein during EVT differentiation from JEG-3-ORGs altered the temporal expression of the known EVT marker genes. Based on the JEG-3 KO (disruption of exons 2 and 3) cell line and the TB-ORGs model, it was determined that HLA-G has a negligible effect on trophoblast invasion and differentiation. Despite this, JEG-3-ORG remains a valuable model for studying trophoblast differentiation.

In this study, the volatile flavor compounds of baked potatoes from different cultivars were identified and analyzed via headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) together with principal component analysis (PCA). Totally, 88 signal peaks were detected, and 64 compounds were identified and classified into 25 aldehydes, 14 alcohols, 11 ketones, 5 esters, 2 furans, 1 pyrazine and others. Based on the signal intensity of the identified compounds, topographic plots and fingerprints were established to investigate the differences caused by cultivars. The main compounds including aldehydes, alcohols, ketones, esters, furan and pyrazine varied with cultivars, which were more abundant in B5 and B6 cultivars. Moreover, PCA and fingerprint similarity analysis clearly showed that these samples are independent and distinguishable. Results also showed that the GC-IMS technique might be helpful and useful in the rapid detection of volatile compounds in cooked potatoes and provide support for the domestic and industrial products.

The lithium isotope composition (δ7Li) of seawater records important information on the evolution of the carbon and silicon cycles over geologic time. Here we report δ7Li values in a suite of Neogene dolostones (23–3.4 Ma, n = 39) from the South China Sea. Over the Neogene, dolostone δ7Li values have increased from 24.9‰ to 30.1‰, overlapping previously published foraminifera records and documenting seawater δ7Li without applying any isotopic fractionation factor correction. Our results suggest that fabric-retentive dolostones are good proxies for providing seawater δ7Li records even after early diagenesis. Importantly, these results provide a high-resolution dolostone record rather than a foraminifera record to confirm the observed ~5‰ increase in Neogene seawater δ7Li. We predict that early marine diagenetic dolostones with fabric textures abundant in the Proterozoic may record changes in seawater δ7Li and continental weathering, providing great insights into the Precambrian global carbon cycle.

The stability assessment of a large power system in real-time is very necessary after it encounters fault. The paper proposes a new model (SVM-GDPSO) for assessing the large power system. In order to enhance SVM, taking tangent vector of power flow Jacobian (PFJ) as the goal of machine learning was used for improving the precision. Besides, particle swarm optimization (PSO) with Gaussian disturbance (GD) is taken for setting the key parameters of SVM, and metalearning was utilized to decrease the search space of PSO. The experiment on the standard test system of IEEE 118-bus demonstrated that this model could reflect the status of large power system in time. Besides, the method could locate the fault area and rank the fault level by the observation of critical bus. The proposed method has the reliability rate 97.22 %, which is superior to the back propagation neural network (BPNN) and SVM-GA, as well as determines the fault area with the success rate of 96.61 %.

Purpose This study aimed to compare total blood loss (TBL) and hidden blood loss (HBL) in patients undergoing single-level open transforaminal lumbar interbody fusion (O-TLIF) and unilateral biportal endoscopic transforaminal lumbar interbody fusion (ULIF). Methods A total of 53 patients who underwent ULIF and 53 patients who underwent O-TLIF from March 2020 to July 2022 were retrospectively reviewed. The Nadler’s formula was employed to estimate the patient’s blood volume (PBV), Gross’s formula to estimate TBL, and Sehat’s formula to estimate HBL. The obtained data were then analyzed with independent t test, chi-squared test, and analysis of covariance. Results TBL and measured blood loss (MBL) in ULIF group (326.86 ± 223.45 ml, 99.00 ± 72.81 ml) was significantly lower than O-TLIF group (427.97 ± 280.52 ml, 270.66 ± 102.34 ml). Nevertheless, the HBL in ULIF group was higher than that in O-TLIF group (227.86 ± 221.75 ml vs 157.31 ± 268.08 ml), however this was not statistically significant (p = 0.143). The HBL was 69.71 ± 23.72% of TBL in ULIF group and 36.76 ± 18.79% of TBL in O-TLIF group. Patients in ULIF group had lower TBL and MBL, shorter duration of drainage, lower postoperative anemia, and shorter postoperative hospital stay compared to those in O-TLIF group. Conclusions Perioperative HBL should not be neglected in patients undergoing ULIF or O-TILF, as it accounts for a large percentage of TBL in both groups. ULIF is associated with lower TBL and MBL, postoperative anemia, shorter postoperative hospital stays compared with O-TLIF.

ObjectiveTo determine whether the two lower extremities are of equal length after hip arthroplasty for femoral neck fractures, we developed a novel method of manual positioning based on anatomical mark (shoulder-to-shoulder) in hip arthroplasty.MethodsPatients with femoral neck fractures requiring hip arthroplasty from July 2020 to March 2022 in the orthopedic department of Jinjiang Municipal Hospital, Fujian Province, China were recruited. Hip arthroplasty was performed using the proposed “shoulder-to-shoulder” method of manual positioning based on anatomical mark in 52 patients with femoral neck fractures who met the inclusion criteria. “Shoulder-to-shoulder” was achieved by alignment of the marked femoral “shoulder” and the “shoulder” of prosthesis stem. There were 16 male and 36 female patients, with 27 undergoing total hip arthroplasty (THA) and 25 undergoing hip hemiarthroplasty (HA). The fractures were categorized according to the Garden classification: type II, type III, and type IV in 5, 11, and 36 patients, respectively. The vertical distance from the apex of the medial margin of the femoral trochanter to the tear drop line on both sides which was regarded as the length of both limbs were compared via postoperative imaging, and the apex–shoulder distance on the ipsilateral side measured via postoperative imaging was compared with those measured intraoperatively.ResultsAll patients completed the surgery successfully. The measurement results for the lower extremities after THA were as follows: contralateral group, 43.87 ± 5.59 mm; ipsilateral group, 44.64 ± 5.43 mm. The measurement results for the lower extremities after HA were as follows: contralateral group, 45.18 ± 7.82 mm; ipsilateral group, 45.16 ± 6.43 mm. The measurement results for the lower extremities after all arthroplasties were as follows: contralateral group, 44.50 ± 6.72 mm; ipsilateral group, 44.89 ± 5.90 mm. The results for the apex–shoulder distance were as follows: postoperative imaging, 19.44 ± 3.54 mm; intraoperative apex–shoulder distance, 27.28 ± 2.84 mm. Statistical analysis results indicated no statistically significant difference in the postoperative bilateral lower extremity length after hip arthroplasty (P = 0.75), while a statistically significant difference was found between the intraoperative and postoperative imaging measurements of the apex–shoulder distance (P ConclusionThe novel method of manual positioning based on anatomical mark (shoulder-to-shoulder) for femoral neck fractures in hip arthroplasty is simple and accurate, making it effective for preventing postoperative bilateral leg length discrepancy.

In this paper we propose the Gini correlation screening (GCS) method to select the important variables with ultrahigh dimensional data. The new procedure is based on the Gini correlation coefficient via the covariance between the response and the rank of the predictor variables rather than the Pearson correlation and the Kendall τ correlation coefficient. The new method does not require imposing a specific model structure on regression functions and only needs the condition which the predictors and response have continuous distribution function. We demonstrate that, with the number of predictors growing at an exponential rate of the sample size, the proposed procedure possesses consistency in ranking, which is both useful in its own right and can lead to consistency in selection. The procedure is computationally efficient and simple, and exhibits a competent empirical performance in our intensive simulations and real data analysis.

Using a space robot to capture a non-cooperative spacecraft with high-speed rotation is significantly challenging since any collision generated during capturing will have great impact on both. To reduce the risk in capturing operations, it is crucial to slow down the rotation velocity of the target before capturing. Hence, this paper studies a collision control strategy for using a robotic arm to detumble a non-cooperative spacecraft. The goal of this strategy is to maintain contact between the robot and the target and to apply continuous detumbling force on the target to slow down its rotational motion. To achieve that, first the mechanism analysis of the two balls for a central collision scenario is performed. Then an overdamping control method is proposed to avoid the separation of the balls after the central collision based on the overdamping property of the mass-spring-damper system, the effectiveness of which is validated theoretically. Finally, to use this overdamping control method in the detumbling missions of space robots, a position-based overdamping control strategy is introduced. In this strategy, the relative dynamic behavior between the robotic arm tip and the contact surface of the target during detumbling is approximated to that of a mass-spring-damper system. Owing to the proposed overdamping control method, the contact between the robot and the target can be maintained, and the space robot can apply continuous control torque to slow down the rotational velocity of the target. Numerical simulations are performed to demonstrate the validity of the proposed control strategy.

Light-driven utilization of CO2 in organic synthesis is highly attractive because it mimics nature. However, such transformations are mainly limited to the incorporation of only a single CO2 molecule into organic compounds, far less than the number of CO2 molecules fixed in the product in photosynthesis. Here we report the visible-light photoredox-catalysed dicarboxylation of alkenes, allenes and (hetero)arenes with the incorporation of two CO2 molecules. This method realizes the formation of multiple C–C bonds with high chemo- and diastereoselectivities under mild conditions, which represents a simple, rapid and sustainable approach to valuable dicarboxylic acids. Moreover, this transition-metal-free protocol exhibits a low catalyst loading, good functional group tolerance, broad substrate scope, facile scalability and easy product derivatizations to give drug and material molecules. Mechanistic studies indicate a pathway by which a visible-light-induced two-electron reduction via sequential single electron transfer generates radical anions of such unsaturated substrates, broadening the repertoire of strategies. Transformations in organic chemistry are mainly limited to the incorporation of only one equivalent of the greenhouse gas CO2 per substrate. Now, a visible-light photoredox-catalysed dicarboxylation of alkenes, allenes and arenes allows the incorporation of two CO2 molecules into organic compounds.

The analysis of vehicle speeds at the moment of traffic accidents is becoming increasingly important. To solve difficult calculations arising from video analysis when the shooting direction of the camera is the same as the driving direction of the vehicles, an improved plane homography method is proposed. This method is based on detecting the frame rate of and extracting all of the key image frames from a surveillance video. Next, a normalizing approach for the control points is proposed to reduce the ill-conditions of matrix calculations when the perspective image is rectified to an orthographic image. The information in the rectified image is then measured and recorded by extracting the mark point information. Finally, the corresponding curve of time and speed for the examined vehicle is created, which can be used to analyze the average braking deceleration of the accident-causing vehicle. This method can directly determine the speed of a vehicle using videos of a traffic accident without any reference to the dimensions of the vehicle itself. Considering an actual traffic accident as an example, the driving trajectories and velocity curves for two vehicles are obtained using this method. The proposed method can effectively overcome the shortcomings of the commonly used speed recognition methods and it is easy to utilize.

PurposeHere, we sought to determine the safety and feasibility of three-dimensional exoscope (3D EX). We compared data on surgery, complications, postoperative drainage, hematology, and clinical outcomes in the group that underwent transforaminal lumbar interbody fusion (TLIF) using an operative microscope (OM) relative to those treated using 3D EX.MethodsWe retrospectively reviewed records on 74 patients who underwent one- or two-level TLIF from August 2019 to October 2020. Repeated measures analysis of variance was used to compare pre- and post-operative visual analogue scale (VAS) scores and oswestry disability index (ODI). We used analysis of covariance to compare pre- and post-operative erythrocyte count (RBC), hemoglobin (Hb), and hematocrit (Hct). Independent sample t-tests was used to compare postoperative drainage volume, total blood loss (TBL), visible blood loss (VBL) and hidden blood loss (HBL).ResultsThere were no significant differences in VAS and ODI scores between the two groups at all time points (all p > 0.05). RBC and HBL did not differ significantly between the two groups (all p > 0.05). There were significant differences in postoperative drainage volume,TBL, Hb, and Hct values when using 3D EX relative to OM in two-level TLIF (all p p > 0.05). The two groups differed significantly with regards to VBL when used for one- or two-level TLIF (all p ConclusionOur data show that 3D EX is a suitable alternative to OM in TLIF. Relative to OM, 3D EX has important strengths in reducing perioperative bleeding in two-level TLIF.

urpose: This study aimed to compare total blood loss (TBL) and hidden blood loss (HBL) in patients undergoing single-level open transforaminal lumbar interbody fusion (O-TLIF) and unilateral biportal endoscopic transforaminal lumbar interbody fusion (ULIF).Methods: A total of 28 patients who underwent ULIF and 30 patients who underwent O-TLIF from March 2020 to October 2021 were retrospectively reviewed. The Nadler’s formula was employed to estimate the patient’s blood volume (PBV), Gross’s formula to estimate TBL, and Sehat’s formula to estimate HBL. The obtained data were then analyzed with independent t test、chi-squared test, and analysis of covariance.Results: TBL and measured blood loss (MBL) in ULIF group (360.00±245.74 ml, 117.43±83.09 ml) was significantly lower than O-TLIF group (542.29±233.25ml, 306.30±108.98ml). Nevertheless, the HBL in ULIF group was higher than that in O-TLIF group (242.57±242.49 ml vs 235.99±236.53 ml), however this was not statistically significant. (P=0.917). The HBL was 67.38± 25.63% of TBL in ULIF group and 43.52±17.39% of TBL in O-TLIF group. Patients in ULIF group had lower TBL and MBL, shorter duration of drainage, lower postoperative anemia, and shorter postoperative hospital stay compared to those in O-TLIF group.Conclusions: Perioperative HBL should not be neglected in patients undergoing ULIF or O-TILF, as it accounts for a large percentage of TBL in both groups. ULIF is associated with lower TBL and MBL, postoperative anemia, shorter postoperative hospital stays compared with O-TLIF.

The development of sequence decomposition techniques in recent years has facilitated the wide use of decomposition-based prediction models in hydrological forecasting. However, decomposition-based prediction models usually use the overall decomposition (OD) sampling technique to extract samples. Some studies have shown that the OD sampling technique causes abnormally “high” performance of models owing to the utilization of future information, and this technique cannot be applied in practice. Several researchers have also proposed novel sampling techniques, such as semi-stepwise decomposition (SSD), fully stepwise decomposition (FSD), and single-model SSD (SMSSD). Moreover, an improved single-model FSD (SMFSD) sampling technique is proposed in this study. Four decomposition methods, namely discrete wavelet transform (DWT), empirical mode decomposition (EMD), complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN), and variational mode decomposition (VMD), are introduced in this study. A systematic investigation of the models developed using OD sampling techniques is conducted, and the applicability of SSD, FSD, SMSSD, and SMFSD sampling techniques is reasonably evaluated. The application of monthly runoff prediction using the five sampling techniques and four decomposition methods at five representative hydrological stations in Poyang Lake, China, shows that (1) EMD and CEEMDAN (including the improved EMD-based adaptive decomposition method) cannot be used to construct stepwise decomposition prediction models because the implementation of the stepwise decomposition strategy leads to a variable number of sub-series. (2) OD sampling techniques cannot develop convincing models for practical prediction because future information is introduced into the samples for model training. (3) Models developed based on SSD and SMSSD sampling techniques do not use future information in the training process, but suffer from severe overfitting and inferior prediction performance. (4) Models developed based on FSD and SMFSD sampling techniques can produce convincing prediction results, and the combination of the proposed SMFSD sampling technique and VMD develops prediction models with superior performance and significantly enhances the efficiency of the models.

For the Cauchy problem to Keller-Segel system, we show well-posedness and time-decay estimates in the critical scaling-invariant Besov spaces by using Littlewood-Paley analysis together with the decay estimates of heat kernels.

In this paper we consider unbounded weighted conditional type (WCT) operators on Lp-space. We provide some conditions under which WCT operators on Lp-spaces are densely defined. Specifically, we obtain a dense subset of their domain. Moreover, we get that a WCT operator is continuous if and only if it is every where defined. A description of polar decomposition, spectrum, spectral radius, normality and hyponormality of WCT operators in this context are provided. Finally, we apply some results of hyperexpansive operators to WCT operators on the Hilbert space L2(?). As a consequence hyperexpansive multiplication operators are investigated.

Multi-DOF flexible space robots play a significant role in the on-orbit service. The flexibility of the robots is mainly caused by the flexible links and some flexible drive elements in joints. The vibration generated by the component flexibility can affect the accuracy of control. In this paper, the dynamics and control issues of flexible-link flexible-joint (FLFJ) space robots considering joint friction are studied. Firstly, the Spong’s model is employed to depict flexible joints, and the Coulomb friction model is adopted to describe joint friction. Then based on the single direction recursive construction method and velocity variation principle, dynamic equations of the system are derived. Secondly, a trajectory of joint motion is given and a trajectory tracking controller with friction compensation is designed with the computed torque method. Finally, several numerical simulations are carried out to verify the accuracy of the dynamic model and illustrate the effect of joint friction and joint flexibility on the dynamic characteristics of space robots. Besides, simulation results suggest that the controller designed in this paper could effectively achieve the trajectory tracking control for the 6-DOF FLFJ space robot with joint friction.

In this paper, the contact control problem of a space robot to grasp a non-cooperative satellite is investigated in detail, and a new capture control strategy is proposed. Firstly, the dynamic equation of the robot system is derived based on the multibody dynamics theory, and a modified Hertz model is used to describe the contact force between the robot end-effector and the target satellite. Then, a novel position-based impedance control strategy for capturing the target satellite is proposed. This control strategy is to capture the target satellite by realizing soft contact between the end-effector and the target satellite, thus the target satellite will not depart from the end-effector after their contact. Different from the other existing capture control strategies, the proposed strategy needs only the kinematic information of the space robot, so the control performance requirement is lower and is easier to implement in practice. To verify the validity of the proposed capture control strategy, simulations are conducted at the end of this paper, and the results indicate that the target satellite can be grasped effectively using the proposed capture control strategy if the motion of the target satellite is translational or tumbling.

Traditional fermented soybean contains a variety of microflora. To obtain a comprehensive and accurate understanding of the microbial community structure and metabolic potential of fermented soybean, comparative metagenomics and metatranscriptomics were performed on a sample of fermented soybean in Yunnan Province. Metagenomic DNA and metatranscriptomic RNA were sequenced using Illumina HiseqTM2500, which yielded a total of 92,192,276 reads, with an average read length of 150 bp and 38,798,262 paired-end sequences, with an average length of 151 bp. The results show that Providencia stuartii was the most abundant species and the genes of carbohydrates (2296, 13.30%), protein metabolism (1530, 8.86%), and amino acids and amino acid derivatives (1423, 8.24%) were dominant. The expression levels of the genes belonging to amino acid transport and metabolism processes were the highest according to the reads per length of transcript in kilo-bases per million mapped reads (RPKM) values, followed by energy production and conversion and carbohydrate transport and metabolism. The metabolic pathways were primarily associated with carbohydrates, proteins and amino acids, which might be in accordance with the high levels of proteins and other nutrients in soybeans. Overall, these findings provide insights into the community structure and metabolic potential of the fermented soybean microbiome.

Rendezvous and docking (RVD) with a tumbling target is challenging. In this paper, a novel control scheme based on motion planning and pose (position and attitude) tracking is proposed to solve the pose control of a chaser docking with a tumbling target in the phase of close range rendezvous. Firstly, the current desired motion of the chaser is planned according to the motion of the target. In planning the desired motion, the “approach path constraint” is considered to avoid collisions between the chaser and the target, and the “field-of-view constraint” is considered to make sure the vision sensors on the chaser to obtain tight relative pose knowledge of the target with respect to the chaser. Then, the difference between the chaser’s motion and the desired motion is gradually reduced by a pose tracking controller. This controller is based on the non-singular terminal sliding mode (NTSM) method to make the tracking error converge to zero in finite time. Since the chaser nearly moves along the desired motion and the motion is reasonable, (1) it could safely arrive at the docking port of the target with a suitable relative attitude, (2) it will be always suitably oriented to observe the target well, and (3) the magnitude of the needed control inputs are less than that in existing literatures. The numerical results demonstrate the above three advantages of the proposed method.

Background: Currently, the identification of Clara cell and type II alveolar epithelial cell-type cancer cells requires electron microscopy, which is a time-consuming and expensive process involving a complicated tissue sampling procedure. The aim of this study was to identify unique biomarkers for Clara cell and type II alveolar epithelial cell-type lung cancer cells, respectively, with proteomic profiling. Methods: Six human lung adenocarcinoma cell lines (A549, NCI-H358, NCI-H1650, HCC827, NCI-H1395, and NCI-H1975) were investigated for their ultrastructural characteristics. The differentially expressed proteins (DEPs) were screened between NCI-H358 cells (Clara cell type) and A549 cells (type II alveolar epithelial cell type) using two-dimensional difference gel electrophoresis (2D-DIGE) and matrix- assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS/MS), and then they were validated by western blot. The protein expression levels of endoplasmic reticulum oxidoreductin 1-α (ERO1L), Clara cell 10-kD protein (CC10), and surfactant protein C (SP-C) were also determined in the six cell lines assayed. Results: NCI-H358 cells featured Clara cell differentiation; A549, NCI-H1975, and HCC827 cells had characteristics of type II alveolar epithelial cells; and NCI-H1395 and NCI-H1650 cells had no differentiation characteristics of any lung adenocarcinoma cell type. Five DEPs including ubiquitin carboxyl- terminal hydrolase isozyme L1 (UCHL1), cytokeratin 19 (CK19), cytokeratin 8 (CK8), ERO1L, and peroxiredoxin 2 (PRDX2) between NCI-H358 and A549 cells were identified for further validation; however, none of them showed suitability as an effective biomarker. Similarly, CC10 and SP-C were not appropriate biomarkers. Conclusions: Cytological subtypes of NCI-H1975 and HCC827 cells were identified, but no promising biomarker was discovered in the present study.

This paper studies the pose tracking control problem for satellite proximity operations between a target and a chaser satellite, by which we mean that the chaser is required to track a desired time-varying trajectory given in advance with respect to the target. Firstly, by consulting an adaptive sliding-mode control method in literature developed for a class of nonlinear uncertain systems, an effective pose tracking controller is obtained. This controller requires no information about the mass and inertia matrix of the chaser, and takes into account the gravitational acceleration, the gravity-gradient torque, the J2 perturbing acceleration, and unknown bounded disturbance forces and torques. Then, an updated controller is proposed by combining the aforementioned controller and the unscented Kalman filter (UKF). This updated controller estimates the inertial parameters of the chaser through UKF, so it is of better adaptive ability to the initial estimation of the inertial parameters. Finally, numerical simulations are given to demonstrate the effectiveness of the proposed controllers. The simulation results show that the updated controller is more accurate.

The fuel optimization of the spacecraft is significant for its service life. In this paper, a fuel optimization method is proposed to solve the fuel optimization problem of the pursuer in the spacecraft pursuit-evasion game (SPE game). This method first takes both the magnitude and direction of the pursuer's thrust as the control variables to be optimized, then models the fuel optimization problem as a two-player zero-sum differential game whose payoff function is the fuel consumption of the pursuer, and finally obtains the optimal control strategy of the pursuer by solving the saddle point of the differential game. Considering that the solving of the saddle point usually leads to the solving of a high-dimensional (12-dimensional in this paper) two-point boundary value problem (TPBVP), which is very challenging, the proposed method adopts a dimension-reduction algorithm which can simplify the TPBVP to the solving of a four-dimensional nonlinear equations and a terminal constraint, and then presents an hybrid numerical algorithm combining the particle swarm optimization algorithm and the Powell algorithm to solve the nonlinear equations and terminal constraint. The simulation results show that the proposed method can achieve the fuel optimization of the pursuer in the SPE game and is robust to the orbital altitude, the initial relative state between the pursuer and evader and the magnitude of the evader's thrust.

Background At present, there are no new method for establishing operative channels for the unilateral biportal endoscopic(UBE)system. Objective This paper describes a new method for establishing operative channels in UBE surgery. Meanwhile, we assessed the preliminary efficacy of unilateral biportal endoscopic discectomy (UBED) in treating degenerative disc disease. Methods We retrospectively reviewed 52 patients who underwent UBED from February 2020 to August 2020 via our new method. The Oswestry Disability Index (ODI) and visual analogue scale (VAS) score were measured preoperatively and 1 month, 3 months, 6 months and 12 months postoperatively. Repeated measures one-way analysis of variance (RM-ANOVA) was performed to compare the pre-and postoperative VAS scores and ODIs. Post hoc pairwise comparisons (paired t-tests) was used to compare the postoperative VAS scores and ODIs. Results The postoperative ODIs and VAS scores of low back pain and leg pain were significantly lower than those before surgery, and differences were statistically significant (all p < 0.05). Further pairwise comparisons brought out significant differences in the ODI at each time point after surgery (all p < 0.008). Significant differences were found in the VAS score of leg pain between 1 month and 6 months, 1 month and 12 months, and 3 months and 12 months (all p < 0.008). Pairwise comparisons in the VAS score of back pain between 1 month and 12 months differences (p < 0.008). Conclusion The modified channel establishment can provide a clear field of view in UBE surgery. UBED can yield a satisfactory curative effect in treating degenerative disc disease.

Traditional power distribution systems in ship field usually adopt power breakers, contactors, relays and fuses as power distribution devices, thus result in low fault response and lack of current-limiting, so loads with high current spikes when started may result in large voltage drop on the DC power bus or misoperation of the power distribution branch, moreover, short-circuit may bring great damage to the whole power system. In this paper, a smart power distribution equipment is proposed, to automatically distinguish different load type and state, realize current-limiting when large capacitive load is started and cut off the power distribution branch whenever short-circuit occurs. This technique greatly increases the smart management capability of the power system. The feasibility and effectiveness of this technique is verified by the experiments carried out on a 24V/2kW prototype.

In this paper, the attitude evolution of a dual-liquid-filled spacecraft with internal energy dissipation is investigated. The dynamic equations of the spacecraft system are established to study various trajectories including major axis spin, period-n limit cycle, and chaotic motion. A criterion is obtained by Melnikov’s method to predict the occurrence of chaotic motion of the system. The effects of system parameters, especially liquid parameters, on the chaotic region, are discussed in detail. The comparison of analytical and numerical results shows that our criterion can accurately separate the chaotic from nonchaotic region of the system in parameter space. Therefore, this paper contributes to avoid the potentially periodic and chaotic motions of spacecraft.

A series of Ca3Gd2W2O12:Mn4+ far-red phosphors were successfully synthesized by high temperature solid state reaction. The crystal phases and morphology of the powders were analyzed by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). The luminescent properties of the samples with varying Mn4+ concentrations were investigated, and the result indicates that prepared phosphor Ca3Gd2W2O12:Mn4+ can be excited by ultraviolet light and exhibit intense far red emission at 710 nm. The optimum doping concentration of Mn4+ is about 0.2 mol %. The internal quantum efficiency of Ca3Gd2W2O12:Mn4+ phosphors are 58.5%. In addition, the mechanism of luminescence is also analyzed by using Tanab-Sugano energy level diagram. The thermal stability of samples have been researched and discussed. Finally, a far-red LED was fabricated by combining a 365 nm near-ultraviolet InGaN chip with Ca3Gd2W2O12:Mn4+ phosphor. All the results indicated that Ca3Gd2W2O12:Mn4+ as an excellent phosphor can be applied to far-red LED lamp and it has potential applications in plant growth.

As typical anisotropic materials combining the entropy elasticity of an elastomer with the self-organization of rigid mesogens, liquid crystalline elastomers (LCEs) possess the emerging application...

We successfully synthesized Sr3Gd2(BO3)4:Eu3+ (SGBO:Eu3+) and Sr3Y2(BO3)4:Eu3+ (SYBO:Eu3+) phosphors through a high-temperature solid-state reaction. The structure was shown by x-ray powder diffraction and the irregular morphology of SGBO:Eu3+ and SYBO:Eu3+ phosphors was seen by a field emission scanning electron microscope. Additionally, the photoluminescence excitation spectra and emission spectra were also presented. As shown in the results, the phosphors could be stimulated by near ultraviolet light and then exhibited red light emission, which is consistent with the calculated color coordinates. The quenching concentrations of Eu3+ in SYBO and SGBO hosts are much higher than that in other borate hosts. In particular, far-red light-emitting at 702 nm due to the transition of 5D0 → 7F4 is beneficial to plant growth. The results show that the prepared samples have application value in white light emitting diodes.

Upon heating, polyesters decompose to small molecules and release flammable volatiles and toxic gases, primarily through chain scission of their ester linkages, and therefore exhibit poor fire-safety properties, thus restricting their applications. Reported herein is an end-group-capturing effect of (bis)oxazoline groups, generated from the thermal rearrangement of the N-(2-hydroxyphenyl)phthalimide (HPI) moiety which was incorporated into the polyester chain by copolymerization. These copolyesters, as a result, exhibit high efficiency in retarding decomposition by capturing the decomposed products, particularly for the carbonyl-terminated fragments, thus increasing the fire-safety properties, such as self-extinguishing, anti-dripping, and inhibiting heat release and smoke production. The successful application of this method in both semi-aromatic and aliphatic polyesters provide promising perspectives to designing versatile fire-safe polymers.

High dynamic non-cooperative space targets generally perform complex motions with large angular velocities, so capturing these targets directly may cause fracture damage to the space manipulator. It is a feasible strategy for this case to reduce the angular velocity of the target to an acceptable range in the pre-capture phase. In this paper, an effective method for detumbling the high dynamic non-cooperative space target is proposed, where the tumbling target spins down under the action of external torque generated by the contact impact. The dynamic model of the detumbling system is established by the Jourdain’s velocity variation principle, and the contact model is built based on the Hertz contact theory and the kinematic and geometric relations between the space target and despin device. The simulation results show that the proposed method can synchronously reduce the angular velocities of the space target in all three body axes.

Space debris is generally a kind of tumbling noncooperative space target which poses a serious threat to human space activities. In active debris removal (ADR) missions, capturing a space target directly may cause damage to space manipulator and chaser satellite, so it is a feasible strategy to reduce the angular velocity of space target to an acceptable range in the pre-capture phase. In this paper, an active detumbling technology for a free-floating tumbling space target with energy dissipation is studied, and an effective detumbling method utilizing intermittent contact impact between the space target and despin mechanism is proposed. First, the dynamic model of the space target is set up by the Jourdain’s velocity variation principle. Then, a contact model between the space target and despin mechanism is established based on the Hertz contact theory and the method of computer graphics. Finally, the detumbling method is validated by numerical simulations. Simulation results show that our method can reduce the angular velocity of the space target effectively without causing large nutation.

Enhanced apoptosis of cardiomyocytes in suffering overloaded saturated fatty acids (SFAs) can result in myocardial infarction and cardiac dysfunction. The function of vascular endothelial growth factor (VEGF) in cardiomyocyte protection was not clearly described. To investigate the preservative effects of VEGF sensitization on ceramide-mediated programmed cell death of cardiomyocytes, palmitate-induced injury in H9c2 cells was established as an in vitro model. Results revealed that 0.5 mM palmitate application effectively led to debased viability and activated apoptotic factors. A significant time-dependent relation between PAL and cardiomyocyte injury was observed. The apoptosis rate was increased greatly after 16 h of treatment with 0.5 mM PAL. In addition, cell viability was restored by VEGF overexpression during treatment with 0.5 mM PAL. Reduced apoptosis rate and expression of caspase 3, Bax, and NF-κB p65 were observed in this process, while boosted Bcl-2, p-JNK/JNK expression and activity of caspase 3 were checked. However, p-ERK/ERK levels did not exhibit a significant change. These findings indicated the protective effects of VEGF in confronting the ceramide-induced cardiomyocyte apoptosis, and would devote therapeutic targets for cardiovascular safeguard in dealing with fatty acid stress.

Motion prediction of space noncooperative target is an important issue for spacecraft on-orbit service. After obtaining high-precision motion prediction results, the chaser can efficiently plan a motion trajectory to approach the target and then capture it. In this paper, a motion prediction method considering J2 perturbation is proposed for a free-floating noncooperative target. The core idea of this method is to identify dynamic parameters of the target, and then realize the motion prediction through a dynamic model of the target that considering J2 perturbation. In the identification of the dynamic parameters, inertia parameters of the target are preliminarily identified first, then a noise-adaptive unscented Kalman filter (UKF) is applied to roughly identify the dynamic parameters, and finally, the identification precision is further improved through optimization. At the end of this paper, the significance of considering J2 perturbation is demonstrated by numerical simulations, and the effectiveness of the proposed method is verified. Simulation results indicate that J2 perturbation has a great influence on the motion prediction of the target and that the proposed method can yield long-time high-precision motion prediction results. Specifically, under the simulation conditions of this paper, the predicted time obtained by the proposed method is longer than 200 s, and the errors of the motion prediction results of the target's attitude and position are less than 2 deg and 0.02 m, respectively.

Potatoes play an important role in ensuring food security. During the COVID-19 epidemic, consumption of processed potato products decreased, and consumption of fresh potatoes increased. China is the world's largest potato producer with more than 4.81 million hectares of area under potato production and 90.32 million metric tonnes of potatoes produced in 2018. This accounts for 27.36% of the world's planting area and 24.53% of the world's potato production. The proportion of potatoes processed in China was about 12% in 2017, mostly dominated by starch production. However, the recent policy of the Chinese government to popularise potato as a staple food has created new markets for processed potato products other than starch. A very few reports have analysed these future trends of the rapidly growing Chinese potato processing industry and its impact within and outside China. This paper provides an overview of the latest developments with a focus on processed potato products such as potato chips, French fries and dehydrated potatoes, and also, due to the unique Chinese diet culture, it highlights the need for more scientific research dedicated towards the development of novel potato-based healthy foods.

Marine carbonates, precipitating from seawater through inorganic geochemical and biogeochemical processes, are considered to have recorded the seawater geochemical signatures reflecting the marine environmental conditions during their formation. However, they are susceptible to post-depositional diagenetic alteration. The redox conditions and chemical composition of the diagenetic fluid may be different from those of the overlying seawater. Therefore, assessing whether carbonate rocks that have experienced variable diagenesis could still preserve primary seawater geochemistry is a prerequisite before inferring ancient marine environments using geochemical tracers such as the cerium anomaly (Ce/Ce*). Here, we investigate rare earth elements plus yttrium (REY) geochemical features of reefal carbonates from the XK-1 core in the Xisha Islands of the South China Sea. We aim to evaluate whether island carbonates have the potential to preserve reliable primary seawater REY geochemical characteristics after experiencing meteoric diagenesis, marine burial diagenesis, or dolomitization. The results show that even after variable diagenetic alteration, all carbonate samples exhibit seawater-like REY patterns, which are characterized by negative Ce anomalies (Ce/Ce* < 1), distinctively high Y/Ho ratios (>44), and uniform depletion of light rare earth elements (LREE) relative to heavy rare earth elements (HREE) ((Pr/Yb)N < 1). This suggests that the original seawater REY signatures are retained, regardless of varying degrees of changes in the mineralogical composition, diagenetic fluid composition, and redox state. The unmodifiable REY characteristics in carbonates during diagenesis can be attributed to three aspects: (1) during meteoric diagenesis, the low REY content of meteoric fluids and the short-term reactions between fluids and carbonates make it difficult to significantly alter the REY composition of carbonates; (2) during marine burial diagenesis, the ubiquitous cementation creates a relatively closed environment that facilitates the inheritance of REY signatures from primary carbonates; (3) during dolomitization, the dolomitizing fluids derived from penecontemporaneous seawater would not destroy but rather promote the preservation of the original seawater REY signatures in dolostones. The Ce/Ce* variations indicate that the Xisha carbonates have been deposited under constantly oxic conditions since the Neogene, consistent with paleontological and redox-sensitive element geochemical evidence.