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Potentilla kleiniana belongs to the family Rosaceae, which distributes in Central Asia, East Asia and Southeast Asia. In China, this plant is mainly found in east, south and southwest provinces. P. kleiniana has been prescribed for the treatment of various diseases in the field of traditional Chinese medicine, such as cough, fever, tuberculosis, mastitis, rheumatoid arthritis. Our previous study found that P. kleiniana had a certain cytotoxicity on tumor cells. The purpose of this paper was to investigate the chemical constituents of P. kleiniana and their cytotoxicity on tumor cells. The 60% ethanol extract of P. kleiniana were isolated by D-101 macroporous adsorptive resins, silica gel, Sephadex LH-20, Toyopearl HW-40F, semi-preparative high performance liquid chromatography and other methods, and their chemical structures were elucidated on the basis of physicochemical properties, NMR and HR-ESI-MS analysis. Meanwhile, all these compounds were evaluated for cytotoxicity against human cervical cancer cell line Hela. The results were as follows: (1) Thirteen lignans were isolated and identified as (+)-pionresinol (1), (+)-8-hydroxypinoresinol (2), (+)-syringaresinol (3), (+)-medioresinol (4), (+)-pionresinol-4-O-β-D-glucopyranoside (5), (+)-8′-hydroxypinoresinol-4-O-β-D-glucopyranoside (6), (+)-8′-hydroxypinoresinol-4′-O-β-D-glucopyranoside (7), (+)-pinoresinol-8′-O-β-D-glucopyranoside (8), schilignan F (9), (+)-pionresinol-4, 4′-O-bisglucopyranoside (10), (+)-lariciresinol-4′-O-β-D-glucopyranoside (11), neoolivil-4-O-β-D-glucopyranoside (12), 3,3′-bis［3,4-dihydro-4-hydroxy-6-methoxy-2H-1-benzopyran］(13). Among them, compounds 1-4, 7, 8, 10, 12, 13 were isolated from genus Potentilla for the first time, and compounds 5, 6, 9, 11 were isolated from P. kleiniana for the first time. (2) Cytotoxicity studies showed that compounds 1, 3 and 4 display certain inhibitory activities against Hela cells with IC50 values of (69.94 ± 1.89), (66.25 ± 2.11), (59.81 ± 1.73) μmol·L-1, respectively. Therefore, the study enriches the chemical constituents of P. kleiniana, and provides a material basis for the development of anti-cervical cancer drugs.

Objective To explore the effect of extended InterTAN intramedullary nail internal fixation in the treatment of elderly femoral intertrochanteric fractures and its influence on hip function and incidence rates of complications. Methods A total of 138 patients with femoral intertrochanteric fractures aged≥60 years admitted to Orthopedics Department of Anhui Medical University Affiliated Hefei Hospital from April 2019 to May 2022 were included. According to the different intramedullary nails during surgery, the patients were divided into short nail group (n=70, standard InterTAN intramedullary nail) and long nail group (n=68, extended InterTAN intramedullary nail). The perioperative conditions (intraoperative blood loss, surgical time, ambulation time, fracture healing time and the rate of internal fixation failure), complications, visual anologue scale (VAS) scores at 1 day, 3 days, 1 month and 3 months after surgery were compared between the two groups. The patients were followed up for 6 months, and Harris scores were compared between the two groups before surgery and at 3 months and 6 months after surgery. Results Compared with short nail group, intraoperative blood loss was more ［(266.15±52.73) mL vs (243.29±46.13) mL, t=2.71, P=0.01］ and surgery time was longer ［(84.21±14.54) min vs (72.57±13.08) min, t=4.95, P＜0.01］ in long nail group (P＜0.05), but the ambulation time ［(9.32±1.74)d vs (11.50±1.67) d, t=7.51, P＜0.01］ and fracture healing time ［(3.36±1.24) months vs (3.85±1.26)months, t=2.30, P=0.02］ were significantly shorter (P＜0.05). There was no statistically significant difference in internal fixation failure rate and incidence of postoperative complications between two groups (P＞0.05). VAS scores of the two groups was gradually decreased, and the difference was significant at different time points within the groups (P＜0.05). VAS scores in long nail group at 1 day, 3 days, 1 month and 3 months after surgery were significantly lower than those in short nail group (P＜0.05). The Harris scores revealed a statistical difference from the aspects of between-group, time-point and interaction (P＜0.05). The Harris scores in the two groups showed an upward trend, and there was a significant difference at various time points (P＜0.05), and the Harris scores in long nail group at 3 months and 6 months after surgery were significantly higher than those in short nail group (P＜0.05). Conclusion Both standard and extended InterTAN intramedullary nail internal fixation can effectively treat elderly femoral intertrochanteric fractures, but extended InterTAN intramedullary nail has faster healed, milder postoperative pain and better hip function recovery.

Objective: To solve the problems caused by the manual sampling inspection in the field of food packaging, such as difficult to operate continuously for a long time, easy to miss and wrong detection, and unreliable detection accuracy and stability. Methods: In this paper, a machine vision-based vacuum sealed texture detecting method for transparent packaging bag was proposed to replace manual detection. The image was preprocessed by algorithms such as ROI extraction, affine transformation and local binary pattern to highlight the texture features. On this basis, the gray level co-occurrence matrix was used to analyze the features of "good" and "defective" sealing texture images. The parameters of gray level co-occurrence matrix were set and the uniformity of texture features was associated with the feature quantity of the parameters of gray level co-occurrence matrix. Finally, the parameters of gray level co-occurrence matrix was used as the input of SVM classifier, and the sealing defects were identified and classified through calculation. Results: This online detection method compares the defect detection results of the vacuum sealing of transparent packaging bags with the manual quality results up to 97.5%. Conclusion: This method has high detection accuracy and good practicability, and can meet the needs of online detection.

Low frequency oscillations in power system with medium-pressure regulating valve of steam turbine occur from time to time， threatening the safe operation of generating units and power system. Three typical low frequency oscillations of power system induced by medium-pressure regulating valve are given. Given the roles of medium-pressure regulating valves in different types of steam turbines， the ways they induce or participate in low frequency oscillations are introduced. It is pointed out that one of the major reasons for low frequency oscillations occurring in deep peaking-shaving units is the reduction of the turbine’s integrated valve position command， resulting in the frequent participation of medium-voltage regulating valves of poor linearity in the power regulation of the units. In view of the current operating environment of thermal power units in China， six specific measures to prevent the medium-pressure valves from participating in low frequency oscillations in power system are given for reference.

Cigarette smoking (CS) causes skeletal muscle dysfunction, leading to sarcopenia and worse prognosis of patients with diverse systemic diseases. Here, we found that CS exposure prevented C2C12 myoblasts proliferation in a dose-dependent manner. Immunoblotting assays verified that CS exposure promoted the expression of cell cycle suppressor protein p21. Furthermore, CS exposure significantly inhibited replication-dependent (RD) histone transcription and caused S phase arrest in the cell cycle during C2C12 proliferation. Mechanistically, CS deregulated the expression levels of Nuclear Protein Ataxia-Telangiectasia Locus (NPAT/p220). Notably, the proteasome inhibitor MG132 was able to reverse the expression of NPAT in myoblasts, implying that the degradation of CS-mediated NPAT is proteasome-dependent. Overexpression of NPAT also rescued the defective proliferation phenotype induced by CS in C2C12 myoblasts. Taken together, we suggest that CS exposure induces NPAT degradation in C2C12 myoblasts and impairs myogenic proliferation through NPAT associated proteasomal-dependent mechanisms. As an application of the proteasome inhibitor MG132 or overexpression of NPAT could reverse the impaired proliferation of myoblasts induced by CS, the recovery of myoblast proliferation may be potential strategies to treat CS-related skeletal muscle dysfunction.

Objective: In order to eliminate the large amount of redundant information in near-infrared spectroscopy and to improve the accuracy of pork quality identification, and to establish a method for rapid identification of pork quality. Methods: Principal component analysis was used to reduce the dimensionality of pork spectrum data and the characteristic wavelengths of pork spectrum were selected. The parameters of the support vector machine （SVM） model were optimized by the salp swarm algorithm. Pork quality recognition model was proposed based on an improved support vector machine optimized by salp swarm algorithm. Results: compared with grey wolf optimization algorithm improved SVM （GWO-SVM）, grid search algorithm improved SVM （Grid-SVM）, particle swarm optimization algorithm improved SVM （PSO-SVM） and SVM, the pork quality recognition model based on SSA-SVM had the highest precision. Conclusion: Pork quality identification model based on PCA and SVM optimized by salp swarm algorithm can effectively improve the accuracy of pork quality identification.

Abstract As a critical node for insulin/IGF signaling, insulin receptor substrate 1 (IRS-1) is essential for metabolic regulation. A long and unstructured C-terminal region of IRS-1 recruits downstream effectors for promoting insulin/IGF signals. However, the underlying molecular basis for this remains elusive. Here, we found that the C-terminus of IRS-1 undergoes liquid-liquid phase separation (LLPS). Both electrostatic and hydrophobic interactions were seen to drive IRS-1 LLPS. Self-association of IRS-1, which was mainly mediated by the 301–600 region, drives IRS-1 LLPS to form insulin/IGF-1 signalosomes. Moreover, tyrosine residues of YXXM motifs, which recruit downstream effectors, also contributed to IRS-1 self-association and LLPS. Impairment of IRS-1 LLPS attenuated its positive effects on insulin/IGF-1 signaling. The metabolic disease-associated G972R mutation impaired the self-association and LLPS of IRS-1. Our findings delineate a mechanism in which LLPS of IRS-1-mediated signalosomes serves as an organizing center for insulin/IGF-1 signaling and implicate the role of aberrant IRS-1 LLPS in metabolic diseases.

In order to protect and utilize water resources in coal mining, academician GU Dazhao has put forward the theoretical framework and technical system of coal mine underground reservoir with “guiding storage and use” as the core after 20 years of technical exploration and engineering practice in Shendong Mining Area. Based on this, the adaptive conditions for the construction of coal mine underground reservoir are discussed, the design system with the core of reservoir site selection, storage capacity design, spatio-temporal sequence of sub-reservoirs, design of coal pillar dam, design of artificial dam and joint, pipe network and roadway layout, water diversion system, safety monitoring system is constructed.

Abstract This multicenter phase-II trial aimed to investigate the efficacy, safety, and predictive biomarkers of toripalimab plus chemotherapy as second-line treatment in patients with EGFR-mutant-advanced NSCLC. Patients who failed from first-line EGFR-TKIs and did not harbor T790M mutation were enrolled. Toripalimab plus carboplatin and pemetrexed were administrated every three weeks for up to six cycles, followed by the maintenance of toripalimab and pemetrexed. The primary endpoint was objective-response rate (ORR). Integrated biomarker analysis of PD-L1 expression, tumor mutational burden (TMB), CD8 + tumor-infiltrating lymphocyte (TIL) density, whole-exome, and transcriptome sequencing on tumor biopsies were also conducted. Forty patients were enrolled with an overall ORR of 50.0% and disease-control rate (DCR) of 87.5%. The median progression free survival (PFS) and overall survival were 7.0 and 23.5 months, respectively. The most common treatment-related adverse effects were leukopenia, neutropenia, anemia, ALT/AST elevation, and nausea. Biomarker analysis showed that none of PD-L1 expression, TMB level, and CD8 + TIL density could serve as a predictive biomarker. Integrated analysis of whole-exome and transcriptome sequencing data revealed that patients with DSPP mutation had a decreased M2 macrophage infiltration and associated with longer PFS than those of wild type. Toripalimab plus chemotherapy showed a promising anti-tumor activity with acceptable safety profiles as the second-line setting in patients with EGFR-mutant NSCLC. DSPP mutation might serve as a potential biomarker for this combination. A phase-III trial to compare toripalimab versus placebo in combination with chemotherapy in this setting is ongoing (NCT03924050).

Resin matrix composites have been widely used in aviation, aerospace and other important frontiers. The application proportion of composites has become an important criterion to measure equipment advancement. Thermoset composite materials are well known difficult to be repeatedly processed and recycled, while thermoplastic composite materials show poor processing performance due to the high melting temperature. Nowadays, the growth of dynamic covalent chemistry has obscured the line between thermosets and thermoplastics, which makes it possible to realize the innovative development of resin matrix composites. In this paper, the fundamental theory of dynamic covalent chemistry and covalent adaptable networks were outlined. The research process of resin matrix composites based on dynamic covalent chemistry was introduced in detail. The resin matrix composites exhibit promising prospect owing to the remoldable, ease to recycle, self-healing and smart actuator applications. Finally, some suggestions were put forward for the development of the composites, such as improving bond exchange reaction mechanism and stress relaxation model, developing high-performance and commercial resin systems, also developing technologies for composites forming, connecting, repairing and recycling based on the characteristics of material.

Abstract Coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 infection has spread rapidly across the world and become an international public health emergency. Both SARS-CoV-2 and SARS-CoV belong to subfamily Coronavirinae in the family Coronaviridae of the order Nidovirales and they are classified as the SARS-like species while belong to different cluster. Besides, viral structure, epidemiology characteristics and pathological characteristics are also different. We present a comprehensive survey of the latest coronavirus—SARS-CoV-2—from investigating its origin and evolution alongside SARS-CoV. Meanwhile, pathogenesis, cardiovascular disease in COVID-19 patients, myocardial injury and venous thromboembolism induced by SARS-CoV-2 as well as the treatment methods are summarized in this review.

Based on the theory of elastic mechanics, rock mechanics and seepage of porous media, the stress-seepage coupling model of pre-extracted gas through ground wells is established. Combined with the specific engineering examples, the influence of ground stress on the pre-extraction gas effect of the ground well is analyzed. The study results indict that: under the action of surface well extraction, the gas pressure of coal seam decreases continuously, and the larger the ground stress is, the slower the gas pressure decreases; as the extraction continues, the gas pressure decreases and the effective stress of the coal increases, the permeability decreases, and due to gas desorption, the pore and fracture of coal seam become larger and the permeability increases, and the permeability of coal seam generally presents a nonlinear increase trend under the joint action of the two effects. The in-situ stress has a significant influence on the extraction efficiency of surface wells, and the two have a negative correlation, that is, with the increase of in-situ stress, the matrix porosity in coal seam decreases and the cracks tend to close, resulting in the decrease of coal seam permeability, and finally the decrease of gas extraction amount.

To reduce negative stiffness structure’s stiffness non-linearity, enhance its stability during entire working displacement range, and expand its allowable working displacement, the optimal design of negative stiffness structure based on magnetic repulsion is proposed, and its structural parameters are also provided. The new negative stiffness structure’s model is established to determine the structural design parameters. According to the change of the new negative stiffness structure’s stiffness curve, we select the structural parameter to meet the design requirements. In order to verify the effectiveness of the proposed negative stiffness structure, we carried out simulation analysis, and the results show that the optimized negative stiffness structure’s stiffness non-linearity is greatly reduced in a relatively longer displacement, and its stiffness stability is promoted substantially compared with the simple triple-magnet negative stiffness structure.

Background: Health-related quality of life (HRQoL) is one of the major focuses of primary care. However, HRQoL instruments used in China are mainly developed from Western countries. Such instruments may not cover all important health concepts valued by the Chinese as health is a culture-specific concept.Objectives: The objectives of this study are to identify culture-specific health dimensions and culture-related health disparities in primary care that are considered important by Chinese living in China.Methods: A purposive sample of 164 adult Chinese (67 healthy persons and 97 patients) were interviewed face to face. In-depth open-ended questions were asked to elicit culture-specific dimensions of quality of life in primary care settings in China.Results: Twelve health dimensions were identified. Five most frequently mentioned dimensions were: mood (N = 52, 31.71%), physical activities (N = 48, 29.27%), work (N = 40, 24.39%), diet (N = 32, 19.51%), and vitality (N = 28, 17.07%). Significantly more healthy persons reported mood (49.25 vs. 19.59%, P < 0.001), mindset (16.42 vs. 0.00%, P < 0.001), and self-care (11.94 vs. 2.06%, P = 0.016) characterizing good HRQoL, while more patients emphasized on work (4.48 vs. 38.14%, P < 0.001). Diet and vitality appeared to be culture-specific dimensions related to health among Chinese.Conclusions: To better adapt or develop HRQoL instruments for Chinese, dimensions or items regarding diet might be included and disparities in the meaning of vitality between Chinese and Western cultures should be considered.

C24H20N8O4MoCo, monoclinic, C2/c (no. 15), a = 19.3535(7) Å, b = 10.0870(4) Å, c = 12.4174(5) Å, β = 97.3700(10)°, V = 2404.08(16) Å3, Z = 4, Rgt(F) = 0.0218, wRref(F2) = 0.0577, T = 298(2) K.

Three kinds of superparamagnetic iron oxide nanoparticles (SPIONs) with different particle sizes prepared by polyol pyrolysis, and the SPIONs contained Fe3O4 crystal phase with average particle sizes of 8.73, 12.57nm and 15.25nm. The nanoparticles have relatively uniform size distribution and good dispersion property and samples were all superparamagnetic at 300K. The aqueous dispersion of SPIONs with different particle sizes and concentrations were treated in alternating current magnetic field(ACMF) with a frequency of 425kHz and a magnetic field amplitude of 5.3kA·m-1 to conduct heating experiments.The relationship between the specific absorption rate (SAR) and the particle sizes of the samples were discussed. The Brownian relaxation time and Neel relaxation time were calculated. The results show that the heating rate of the aqueous samples increases with the increase of the particle sizes. When the initial temperature is 20℃, the increments of the temperature of 25, 27℃ and 35℃ in 480 seconds are measured for the three nanoparticle solutions (2mg·mL-1) with nanoparticle sizes of 8.7, 12.6nm and 15.3nm, respectively. The Neel relaxation time is shorter than the Brownian relaxation time, indicating that Neel relaxation dominates heating in this system. The larger the particle size is, the higher the SAR value will be, and the highest SAR value is 810W·g-1. The SAR value is negatively correlated with the concentration of the aqueous dispersion.

Quasi-static compression experiments on graphene-reinforced aluminum matrix composites were carried out by means of microcomputer controlled electronic universal testing machine, while dynamic behavior of the composites at various high strain rates was determined by split hopkinson pressure bar (SHPB). In addition, scanning electron microscopy (SEM) was employed to examine the morphological feature of aluminum matrix composites reinforced respectively by grapheme and SiC. The results show that at all strain rate, the yield strength of aluminum is improved both with addition of graphene and SiC, by incorporation of graphene, the yield strength of aluminum is improved more significantly, but without affecting the strain hardening rate of the material. In comparison with SiC as reinforcements, use of graphene undermines strain rate sensitivity of the composites, and meanwhile results in a decline in ultimate strength. J-C and Z-A constitutive models were fitted respectively to the experimental results to obtain relative parameters. Comparison between the two models suggests that J-C model is more accurate in terms of describing stress-strain behavior of both composites reinforced respectively by graphene and SiC.

By means of calculating stacking fault energy(SFE), measuring creep properties and contrast analysis of dislocation configuration, the influence of the temperature on the stacking fault energy and the creep mechanism of a single crystal nickel-based superalloy was investigated. Results show that there is a lower stacking fault energy(SFE) of the alloy at 760℃, and the deformed mechanism of the alloy during creep is the cubical γ' phase sheared by 〈110〉 super-dislocation which may be decomposed to form the configuration of (1/3)〈112〉 super-Shockley partials dislocation plus the super-lattice intrinsic stacking fault(SISF). But the stacking fault energy of the alloy increases with temperature, so the deformed mechanism of the alloy during creep at 1070℃ is the screw or edge super-dislocation shearing into the rafted γ' phase. The SFE of the alloy at 980℃ is in the middle value of the SFEs between 760℃ and 1070℃, the main deformed mechanism of the alloy during creep is the screw or edge super-dislocation shearing into the rafted γ' phase. And some super-dislocation shearing into γ' phase may cross-slip from {111} to {100} planes to form the K-W locks configuration of (1/2)〈110〉 partials plus the anti-phase boundary(APB). The K-W locks with non plane core structure may restrain the slipping and cross-slipping of dislocations to improve the creep resistance of alloy. Wherein, the lower strain rate during creep releases too less deformed heat to activate the dislocation in the K-W locks for re-slipping on {111} plane, which is thought to be the main reason of the K-W locks kept in the alloy during creep at 980℃.

The creep behavior of a containing 4.5%Re/3.0%Ru single crystal nickel-based superalloy at elevated temperatures was investigated by means of creep properties measurement and microstructure observations to specimens in different creep stages by SEM and TEM. Results show that the alloy exhibits good creep resistance at high temperature, and the creep life of the alloy at 1040℃/160MPa reaches 725h. During creep at high temperature, the γ' phase in alloy transforms into the N-type rafted structure along the direction vertical to the stress axis, the deformation mechanism of alloy during steady state creep is dislocations slipping in γ matrix and climbing over the rafted γ' phase. In the latter period of creep, the deformation mechanism of alloy is dislocations slipping and shearing into the rafted γ' phase. The alternate slipping of dislocations results in the twist of the rafted γ' phase to promote the initiation and propagation of the cracks along the interfaces of γ/γ' phases up to creep fracture, which is thought to be the fracture mechanism of alloy during creep at high temperature.

By means of creep property measurements and microstructure observations,an investigation has been made into creep behaviors,deformation and damage mechanism of a 4.5%(mass fraction,the same below) Re-containing,nickel-based single crystal superalloy at 980℃.Results show that,under the condition of 980℃/300MPa,the creep life of 4.5% Re alloy is 169h.In the initial stage of creep,the cubical γ'phase in alloy is transformed into the N-type rafted structure perpendicular to the stress axis.During the steady stage creep,the deformation mechanism of the alloy is dislocations slipping in γ matrix and climbing over the rafted γ'phase.In the last stage of creep,the deformation mechanism of alloy is dislocations slipping in γ matrix and shearing into the rafted γ'phase.On the one hand,the γ matrix channels with narrower feature increases the resistance of dislocations slipping;on the other hand,the super-dislocations shearing into the rafted γ'phase may cross-slip from{111}plane to{100}plane to form the dislocation configuration of K-W locks,which may restrain the slipping and cross-slipping of dislocations to improve the creep resistance of alloy.Moreover,the alternate activation of the primary/secondary slipping dislocations results in the twisting of the rafted γ'phase to promote the initiation of the cracks on the γ'/γ interfaces,and as the creep goes on,the cracks propagate along the direction perpendicular to the direction of stress axis,up to creep fracture,which is thought to be the fracture mechanism of the alloy during creep.

With the improvement of information level, the information attack will cross the boundary of power grid information space and cause the disturbance of power grid physical system, which will form a cross-space chain fault and affect the safe operation of power grid. Based on this, this paper proposes a distribution network node risk assessment method based on information physical fusion. Firstly, the overall structure of the distribution network and the information physical coupling characteristics of the information physical fusion are studied. Then, the cross-space chain failure scenario of distribution network with information physical fusion is analyzed. Based on this, the risk assessment method is proposed. Finally, the effectiveness of the method is verified by a numerical example.

Background: Protein structural alignment is one of the most fundamental and crucial areas of research in the domain of computational structural biology. Comparison of a protein structure with known structures helps to classify it as a new or belonging to a known group of proteins. This, in turn, is useful to determine the function of protein, its evolutionary relationship with other protein molecules and grasping principles underlying protein architecture and folding. Results: A large number of protein structure alignment methods are available. Each protein structure alignment tool has its own strengths and weaknesses that need to be highlighted. We compared and presented results of six most popular and publically available servers for protein structure comparison. These web-based servers were compared with the respect to functionality (features provided by these servers) and accuracy (how well the structural comparison is performed). The CATH was used as a reference. The results showed that overall CE was top performer. DALI and PhyreStorm showed similar results whereas PDBeFold showed the lowest performance. In case of few secondary structural elements, CE, DALI and PhyreStorm gave 100% success rate. Conclusion: Overall none of the structural alignment servers showed 100% success rate. Studies of overall performance, effect of mainly alpha and effect of mainly beta showed consistent performance. CE, DALI, FatCat and PhyreStorm showed more than 90% success rate.

C23H21N3O2, triclinic, P1̅ (no. 2), a = 10.305(3) Å, b = 10.4528(16) Å, c = 10.6351(17) Å, b = 101.139(4)°, V = 983.4(4) Å3, Z = 2, Rgt(F) = 0.0559, wRref(F2) = 0.1607, T = 295(2) K.