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Aiming at disadvantages of particle swarm optimization in the path planning of mobile robots, such as low convergence accuracy and easy maturity, this paper proposes an improved particle swarm optimization algorithm based on differential evolution. First, the concept of corporate governance is introduced, adding adaptive adjustment weights and acceleration coefficients to improve the traditional particle swarm optimization and increase the algorithm convergence speed. Then, in order to improve the performance of differential evolution algorithm, the size of the mutation is controlled by adding adaptive parameters. Moreover, a "high-intensity training" mode is developed to use the improved differential evolution algorithm to intensively train the global optimal position of the particle swarm optimization, which can improve the search precision of the algorithm. Finally, the mathematical model for robot path planning is devised as a two-objective optimization with two indices, i.e., the path length and the degree of danger to optimize the path planning. The proposed algorithm is applied to different experiments for path planning simulation tests. The results demonstrate the feasibility and effectiveness of it in solving mobile robot path planning problem.

Robotic grasping has been widely used in various industries. How to meet the requirements of grasping accuracy and grasping speed at the same time is a challenging problem in real-time grasping tasks. In this paper, aiming at the real-time grasping task in retail warehousing, a lightweight grasping pose estimation model for retail warehousing is proposed. The model first uses the Focus module to perform lossless double downsampling, and learns each feature map of the upper layer through the dilated convolution block to expand the receptive field; then, the R-Resblock structure is improved to perform multi-scale feature fusion, and a lightweight RFB-SE module is designed to enrich feature information and reduce the number of parameters. Finally, after upsampling and restoring the image, the grasping quality, grasping angle, and grasping width of the target are regressed to obtain the optimal grasping pose of the target item. Experiments are carried out in the Cornell dataset, Jacquard dataset, and simulation environment respectively. The experimental results show that the method has a grasping accuracy of 97.8% and a grasping speed of 78FPS on the Cornell dataset. The success rate is 91.5%, and the grasping task in a retail warehouse environment is simulated in grasping simulation experiments.

To evaluate the residue behavior and risk of pyraclostrobin and tebuconazole in peppers, an analytical method for the determination of these two fungicides in peppers was developed using Ultra-high Performance Liquid Chromatography-triple quadrupole mass spectrometry (UPLC-MS/MS). Pepper samples were extracted with acetonitrile, and cleaned up with primary secondary amine (PSA) and graphitized carbon black (GCB). The average recoveries for three fortification levels of pyraclostrobin and tebuconazole in peppers were 86.7-101.4% and 81.7-104.4% with relative standard deviations (RSDs) of 4.0-7.2% and 3.8–10.9%, respectively. The limit of quantifications (LOQs) for the two fungicides in peppers were 0.01 mg/kg. Terminal residue trial of 30% pyraclostrobin and tebuconazole suspension concentrate (SC) on peppers was investigated under open fields and greenhouses conditions. The results showed that the terminal residues of pyraclostrobin and tebuconazole in peppers were lower than the maximum residue limits (MRLs) of peppers established by GB 2763 − 2021 (0.5 mg/kg for pyraclostrobin and 2 mg/kg for tebuconazole). A statistical t-test was used to study the significant difference between open fields and greenhouses, and the results indicated that there is no significant difference between different planting conditions of greenhouses and open fields. Using international estimate of short-term intake (IESTI) calculation model of Joint FAO/WHO Meeting on Pesticide Residues (JMPR), the acute dietary exposure risk of two fungicides in peppers was acceptable for general population with the IESTIs varied from 0–3% of ARfD for pyraclostrobin and 0–5% for tebuconazole.

This paper discusses the imaging diagnostic features of arteriosclerotic encephalopathy and combines the spatial context information of local features to study the clinical imaging image copy detection algorithm. Moreover, this paper proposes a clinical imaging copy detection algorithm that combines the BOW model and spatial context embedding and a clinical imaging copy detection algorithm that combines the BOW model and global context verification. In addition, this paper applies the algorithm to the imaging diagnostic features of arteriosclerotic encephalopathy and sets up a controlled experiment to start research. The experimental research shows that the application of imaging diagnosis to the detection of subcortical arteriosclerotic encephalopathy has good clinical effects and rapid remission of patients’ symptoms. The effectiveness of this method can be verified by a large number of clinical practices in follow-up studies.

Objective: In China, there are two major medical insurance models: the Urban Basic Medical Insurance (UBMI) and the New Cooperative Medical Scheme (NCMS). The aim of the present study was to evaluate the association of the medical insurance type of patients undergoing hemodialysis (HD) with their survival. Methods: We retrospectively analyzed the end-stage renal disease adult patients initiating HD between January 2010 and December 2014 in Zhejiang province, followed up through 31 December 2015. Patients who had received HD for over 3 months were separated into two groups, based on different medical insurance type. Demographic, clinical data, and clinical outcomes were analyzed. The survival rates were calculated by using the Kaplan–Meier method. Results: A total of 6779 patients (59 ± 16 years old, 4331 males (63.9%)) with UBMI and 7177 (59 ± 16 years old, 3778 males (52.8%)) with NCMS enrolled from 226 hemodialysis units. Compared with UBMI group, patients with NCMS had a smaller percentage of hypertensive nephropathy, diabetes mellitus and arteriovenous fistula, faced with more problems in anemia, hypoalbuminemia and metabolism of calcium and phosphorous. The 1-, 3- and 5-year survival rates were 95.4%, 84.4%, and 74.1% in UBMI group, 93.1%, 79.7%, and 67.7% in NCMS group, respectively. Patients with NCMS showed higher all-cause mortality compared with UBMI (p

Objective To investigate the involvement of microRNAs (miRNAs) in the pathogenesis of obstructive sleep apnea-hypopnea syndrome (OSAHS). Methods In this study, we investigated miRNA profiles in the upper airway (UA) skeletal muscles of four patients with OSAHS and four matched controls using the miRCURY miRNA array. In another cohort of 12 OSAHS cases and 7 controls, the mRNA expression levels of interleukin (IL)-6 and Lin-28 homolog A (Lin28A), targets of the downregulated let-7 family members, were measured by real-time quantitative-PCR. The potential targets of the miRNAs were predicted by miRNA target prediction databases miRanda, Microcosm, and Targetscan. Results The array identified 370 differentially expressed miRNAs, of which 181 were upregulated and 189 were downregulated in OSAHS patients (based on a fold-change >2.0 and p Conclusion This study demonstrated profoundly altered miRNA expression profiles in upper airway muscular tissues of patients with OSAHS, which might contribute to the formation and development of OSAHS.

We, the Editor and Publishers of Renal Failure, have retracted the following article: Xi Yao, Shaohua Chen, Wenhua Lei, Nan Shi, Weiqiang Lin, Xiaoying Du, Ping Zhang & Jianghua Chen, The relationship between hemodialysis mortality and the Chinese medical insurance type, Renal Failure, 41:1, 2019, 742–749, https://doi.org/10.1080/0886022X.2019.1652648. The above article has been retracted due to Publisher error as it is an earlier version of an article that was ultimately accepted and published in Renal Failure. The retracted article will remain online to maintain the scholarly record, but it will be digitally watermarked on each page as “Retracted”.

Background There are conflicting research results about the survival differences between hemodialysis(HD) and peritoneal dialysis (PD). The present study estimated the survival and the relative mortality hazard for incident HD and PD patients with end stage renal disease (ESRD) in eastern China. Methods This study examined a cohort of patients with ESRD who initiated dialysis therapy in Zhejiang province between Jan of 2010 and Dec of 2014, followed up until the end of 2015. PD patients were matched in a 1:1 fashion with HD patients, and Kaplan–Meier analysis was used to explore the survival of them. The Cox proportional hazard regression model was applied to identify the factors that predict survival by treatment modality. Subgroup analyses were conducted by stratifying patients according to gender, age, causes of ESRD and comorbidities. Results Among a total of 22,379 enrolled patients (17,029 HD patients and 5350 PD patients), 5350 matched pairs were identified, and followed for a median of 29 months (3 ~ 72 months). Kaplan-Meier survival curve revealed that overall mortality rate was significantly higher in HD patients than in PD patients (log-rank test, P Conclusions ESRD patients who initiated dialysis with PD yielded superior survival rates compared to HD. Increased use of PD as initial dialysis modality in ESRD patients could be encouraged in Chinese population.

Pigment content is an important quality attribute in the grape industry, and anthocyanins are the major fruit pigments. iso-PhABA is a novel and excellent ABA analog capable of the antimetabolic inactivation of ABA. In this study, we found that iso-PhABA improved the coloration of grape berries more obviously than ABA at concentrations of 2 mg/L and 5 mg/L in two grape varieties in China. iso-PhABA treatment enhanced the anthocyanin content in the two grape varieties; specifically, the anthocyanin and delphinidin contents increased in both the ‘Jufeng’ and ‘Xiahei’ varieties. An enzymatic activity test showed that iso-PhABA significantly promoted four key enzyme activities catalyzing anthocyanin biosynthesis. We also determined the affinity between iso-PhABA and ABA receptors using ABA as a control. The results indicated that iso-PhABA had significantly to moderately higher affinities for some ABA receptors, including PYR1, PYL2, PYL1, PYL3 and PYL10, which resulted in higher inhibition of the PP2C HAB1 in the presence of iso-PhABA than in the presence of ABA. iso-PhABA treatment increased the content of soluble sugars and grape yield without any apparent accompanying adverse effects on the quality of the grapes.

To develop new phenazine carboxylic acid derivatives with better phloem mobility, five novel 7-amino acid substituted phenazine-1-carboxylic acids were synthesised by introducing amino acids into PCA at the 7-position. The phloem mobility experiments in Ricinus communis seedlings showed that retaining the carboxyl group of PCA and conjugating amino acids to its phenazine ring can also endow PCA with phloem mobility. Comparing our previous research, we found the amino acids substituted at 7-position on phenazine ring of PCA could clearly enhance the phloem mobility of PCA than that of amino acids conjugated with carboxyl group. Especially, the phloem transport concentration of the compound 7-L-isoleucine substituted PCA (7d) was 21 times higher than PCA-L-isoleucine conjugate (8d). These data suggest that the introduction of amino acids at different structural sites on the phenazine ring could effectively enhance the phloem mobility of PCA and it is worth a further study.

For any positive integer D which is not a square, let (u 1, v 1) be the least positive integer solution of the Pell equation u 2 − Dv 2 = 1, and let h(4D) denote the class number of binary quadratic primitive forms of discriminant 4D. If D satisfies 2 l D and v 1h(4D) ≡ 0 (mod D), then D is called a singular number. In this paper, we prove that if (x, y, z) is a positive integer solution of the equation x y + y x = z z with 2 | z, then maximum max{x, y, z}

Background Pyribenzoxim is an excellent herbicide that can effectively control barnyard grass. However, there are few reports of its structural analogs and structure-activity relationship (SAR), which makes pyribenzoxim an isolated case. Here, a series of diarylmethanone oxime esters characterized by pyridine heterocycles were designed and synthesized for herbicidal screening and SAR investigation against barnyard grass. Results At greenhouse treatment concentrations of 1.17-37.5 μg mL-1 , the title compounds showed a positive dose-toxicity correlation toward barnyard grass plants, with the damage becoming progressively more serious over time. At a concentration of 18.75 μg mL-1 and above, obvious damage was observed in 3 days, most plants died in 7 days, and all died in 14 days. Different degrees of damage were also seen when the concentration was lower than 9.38 μg mL-1 . The selected compounds 5-20 and 5-21 showed excellent control against Echinochloa crusgalli (L.) Beauv., Leptochloa chinensis (L.) Nees, Cyperus difformis L. and Lindernia procumbens (Krock.) Philcox in paddy fields, which was slightly better than that of pyribenzoxim. Conclusion SAR analysis of greenhouse data revealed that the type and position of substituents on aromatic rings greatly influenced the activity of the compounds, although log P values showed no obvious correlation with activity. Combined with compounds 5-20 and 5-21, which showed moderate and excellent activity in greenhouse experiments, and excellent activity in controlling barnyard grass in the field, we conclude that pyribenzoxim analogs probably act as prodrugs, and this could be a focus of attention in future studies on structural optimization of the herbicide. © 2020 Society of Chemical Industry.

Background Conjugating an amino acid onto existing fungicidal parent structures has been demonstrated to be an effective way to endow non-phloem mobile fungicides with phloem mobility. To alter the systemicity of the fungicide PCA (phenazine-1-carboxylic acid), 10 amino acids derivatives of this fungicide were designed and synthesized, and their synthesis, characterization, phloem and xylem mobility in Ricinus communis L, and their fungicidal activity in vitro are described. Results The systemicity experiments in Ricinus communis system demonstrated that all conjugates exhibited obvious phloem mobility compared with non-phloem-mobile PCA, and the introduction of an L-amino acid to PCA more greatly enhanced the phloem mobility. The five D-amino acid conjugates exhibited higher xylem mobility than that of PCA and of each corresponding L-amino acid conjugate. Most conjugates were found to exhibit moderate in vitro fungicidal activities against six pathogenic fungi, which were lower than that of PCA. The results of the bioassay showed fungicidal activities of PCA-amino acid conjugates associated not only with different amino acids, but also with their conformation. Conjugation with D-amino acid contributed to the in vitro fungicidal activities of PCA-amino acid conjugates. Conclusions The current research offers a new strategy for enhancing the systemicity of non-phloem-mobile fungicides and presents some useful information on the effects of introducing amino acids of different steric configurations on the fungicidal activity, phloem and xylem mobility of the parent fungicide. © 2019 Society of Chemical Industry.

Structural Health Monitoring (SHM) is of great importance for the preventive protection of historical buildings. Real-time monitoring and early warning of the structural response have advantages of timeliness and early detection of abnormal structural conditions. Feiyun Wood Pavilion, a historical timber building in China, was taken as the object to study the early warning mechanism for real-time monitored structural responses. An early warning mechanism for historical timber building has been presented under different data accumulated time. The early warning thresholds of structural responses based on statistical and extreme value analysis of the accumulated monitoring data are proposed. Early warning for substructure of the building is realized by data fusion based on the efficiency coefficient method. The effectiveness of the proposed mechanism was verified by real monitoring data. The proposed mechanism gives an early warning solution of the SHM that can be references for existing and other historical buildings.

We prepared 16 novel hydroxybenzoic acid ester conjugates of phenazine-1-carboxylic acid (PCA) and investigated their biological activity. Most of the synthesized conjugates displayed some level of fungicidal activities in vitro against five phytopathogenic fungi. Nine conjugates 5b, 5c, 5d, 5e, 5h, 5i, 5m, 5n and 5o (EC50 between 3.2 μg/mL and 14.1 μg/mL) were more active than PCA (EC50 18.6 μg/mL) against Rhizoctonia solani. Especially conjugate 5c showed the higher fungicidal activity against Rhizoctonia solani which is 6.5-fold than PCA. And the results of the bioassay indicated that the fungicidal activity of conjugates was associated with their LogP, and the optimal LogP values of the more potent fungicidal activities within these conjugates ranged from 4.42 to 5.08. The systemic acquired resistance induced by PCA–SA ester conjugate 5c against rice sheath blight disease in rice seedlings was evaluated. The results revealed that PCA–SA ester conjugate 5c retained the resistance induction activity of SA against rice sheath blight. Electronic supplementary material The online version of this article (10.1186/s13065-018-0478-2) contains supplementary material, which is available to authorized users.

Taking natural product phenazine-1-carboxamide (PCN) as a lead compound, a series of novel phenazine-1-carboxylic acid diamide derivatives were designed and synthesised. Their structures were confirmed by 1H-NMR and HRMS. The bioassays showed that some of the target compounds exhibited promising in vitro fungicidal activities, and exhibited excellent and selective herbicidal activities. Particularly, compounds c, h, o and s displayed root length inhibition activities against barnyard grass with the rate of more than 80%. Compound c exhibited the best activity among all the target compounds against barnyard grass stalk length with the IC50 value of 0.158 mmol/L, and compound o exhibited the best and wide spectrum inhibition against barnyard grass root length and rape in both root length and stalk length herbicidal activities with its IC50 values of 0.067, 0.048 and 0.059 mmol/L respectively. The analysis of preliminary Structure-Activity Relationships provides the theoretical basis for further design of phenazine-1-carboxylic acid.

Additional file 1. Spectrum data of PCA derivatives. Which includes the copies of 1H NMR and HRMS of selected compounds.

Phenazine-1-carboxylic acid (PCA) is a natural product that has been proven effective against a number of soil-borne fungal phytopathogens and registered for biofungicide against rice sheath blight in China. In order to improve the phloem mobility of phenazine-1-carboxylic acid (PCA), four PCA derivatives were designed and synthesized by conjugating PCA with l-alanine methyl ester, d-alanine methyl ester, l-alanine and d-alanine respectively. In vitro and planta bioassays results showed that conjugates L-PAM and D-PAM exhibited higher fungicidal activities against Rhizoctonia solani Kuhn than PCA while L-PA and D-PA were less active than PCA. The concentration of conjugates in Ricinus communis phloem sap was determined by HPLC. The results showed that only L-PA exhibited phloem mobility among these conjugates, and its concentration in Ricinus communis phloem sap increased with the increase of time (the maximum concentration was 12.69μM within 5h). However, the results of pot experiments showed that L-PA and other conjugates didn't exhibited the inhibition for the growth of Rhizoctonia solani Kuhn in the lower leaves after treatment in the upper leaves of rice seedlings. This may be due to the poor plant absorbility for them or their too little amount of accumulation in the lower leaves.

Optically active gels based on helical N-propargylamide polymers were prepared using a one-pot two-step methodology: the pre-formation of helical N-propargylamide copolymer (defined as N=N-HP) and the preparation of gels bearing the helical copolymers. To prepare N=N-HP, N-propargylamide M1, which contained -N=Nfunctional group, and M2, which provided helical polymer chains for the resulting copolymers, underwent copolymerizations in the presence of (nbd)Rh+B-(C6H5)4 as a catalyst. -N=N- groups in N=N-HP acted as an initiator to induce the free radical polymerization of styrene, yielding the designed gels. Trimethylol propane triacrylate (TMPTA) was used to improve the cross-linking degree of the gels. The obtained gels were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and circular dichroism (CD) spectroscopy measurements. The gels showed high optically activity, resulting from the helical structures of the N-propargylamide polymer chains. Preferential adsorption towards (R)-(+)-1-phenylethylamine in the two enantiomers was observed in the obtained gels, demonstrating the potentials of such gels in chiral recognition and chiral resolution. Open image in new window

EAST control system has been developed as network-based distributed control system composed of several subsystems. The integrated control system includes a supervisory control system, many local control systems, machine control and safety interlocks, data acquisition and management. The discharge control system, which is implemented in part of the CODAC (COntrol, Data Access and Communication) system, performs the discharge sequence execution. The development of the EAST integrated control system and commissioning results is presented in this paper.

The development and utilization of outstanding germplasm in breeding programs can expedite breeding process. The high yielding variety Mianmai 37, grown widely in southwestern China, has been used widely in breeding programs. Comparisons between Mianmai 37 and its derivatives for yield and yield components were conducted. Simple sequence repeat (SSR) markers were used to test the frequency of specific alleles transferred from Mianmai 37 to its derivative culti-var Mianmai 367. The results indicated that the yield of the derivative cultivars was significantly higher than Mianmai 37, due to an increased grain number per spike. Favorable traits from Mianmai 37 such as resistance to stripe rust, were trans-ferred to its derivatives. At molecular level, 78.9% loci in Mianmai 367 were derived from Mianmai 37 with 75.0, 83.6 and 74.2% from A, B and D genomes, respectively. Mianmai 367 shared common loci with its parent Mianmai 37, such as re-gions Xgwm374-Xbarc167-Xbarc128-Xgwm129-Xgwm388-Xbarc101 on chromosome 2B and Xwmc446-Xwmc366- Xwmc533-Xbarc164-Xwmc418 on chromosome 3B, these regions were associated with grain number, 1000-kernel weight and resistance. The preferred transmission of alleles from Mianmai 37 to its derivatives probably can be explained by the strong selection pressures because of its favorable agronomic traits and the disease resistance.

Background Hemodialysis (HD) patients are at high risk of infection by hepatitis B virus (HBV) or hepatitis C virus (HCV). The present study was designed to determine the impact of quality control measures on the prevention of transmission of blood-borne viruses. Methods A total of 6182 adult maintenance HD patients from all HD units in Zhejiang Province were recruited on January 1, 2007. The baseline demographic and clinical characteristics were recorded and all patients were followed up until death or survival at 4 years later. The Quality Control Standards of Hemodialysis were gradually implemented in HD units. The HBV or HCV seroconversion rates of the recruited patients were calculated and compared every year during the observation period. Results The prevalence of HBV was 8.3% at the beginning of the study, and 6.6% for HCV. With the implementation of the HD quality control measures, the HBV seroconversion rate tended to decrease year by year (χ2=6.620, P=0.085), and the HCV seroconversion rate decreased significantly (χ2=10.41, P=0.015). Compared with the data in 2007, the HBV seroconversion rate (χ2=4.204, P=0.040, relative risk ratio 0.393, 95% CI 0.156–0.991) and the HCV seroconversion rate (χ2=7.373, P=0.007, relative risk ratio 0.386, 95% CI 0.189–0.787) decreased significantly in 2010. Conclusion Quality control measures for HD decreased the seroconversion rates of HBV or HCV in HD patients, showing that updated quality control measures reduce the risk for transmission of blood-borne viruses in the HD population.

The main purpose of this paper is to study the properties of the Smarandache LCM function SL(n), and give an asymptotic formula for its mean value.

The main purpose of this paper is using the elementary methods to study the properties of the integer part of the m-th root and the largest m-th power not exceeding n,and give some interesting identities involving these numbers.

In the title compound, C24H28N2O4, the dioxalane ring has an envelope conformation. The cyclohexane ring adopts a chair conformation. The dihedral angle between the benzene rings is 72.5 (3)°. The molecular conformation is stabilized by two intramolecular O—H...N hydrogen-bonding interactions with an S(6) graph-set motif. The crystal structure is stabilized by van der Waals interactions.

Copolymerizations of two novel N-propargylamide monomers [HCCCH2NHCOR, in M1, R: CHCH2; in M2, R: CH2CH2CH2CHCH2] with the other two N-propargylamide monomers (M3: achiral monomer; M4: chiral monomer), which were synthesized previously, were carried out in varied monomer feed ratios in the presence of (nbd)Rh+B−(C6H5)4, with the aim to prepare optically active polymers simultaneously possessing helical polymer backbones and pendent polymerizable vinyl groups. Among the four homopolymers derived from M1–M4, polymer 1 and polymer 2 cannot dissolve completely in any of the usual solvents, while polymer 3 and polymer 4 are known to form stable helical conformations. The expected copolymers were obtained in high yields (≥95%) and exhibited good solubility in several organic solvents. The obtained copolymers were found to adopt stable helical structures under the investigated conditions. The as-prepared helical copolymers bearing vinyl groups were further employed as macromonomers to copolymerize with N-isopropylacrylamide (NIPAM) in chloroform at 55 °C using 2,2′-azobis(isobutyronitrile) as an initiator and N,N′-methylenebisacrylamide as a cross-linking agent. The copolymerizations took place smoothly, quantitatively providing hydrogels containing helical polymer chains preformed in the first copolymerization step. The helical structures remained in the hydrogels according to circular dichroism spectroscopy measurements. The hydrogels preferentially adsorbed D-tryptophan and (R)-(+)-1-phenylethylamine in the corresponding two enantiomer pairs, demonstrating the potential applications of the novel optically active hydrogels in the areas of chiral recognition and chiral resolution.