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In order to improve the classification performance of the model for different kinds of arrhythmias, a parallel classification model of arrhythmia based on DenseNet-BiLSTM is researched and proposed. Firstly, the model adopts a parallel structure. After wavelet denoising and heartbeat segmentation of ECG signals, this model can simultaneously capture the waveform features of small-scale heartbeat and large-scale heartbeat containing RR interval; Then, based on deep learning, Densely connected convolutional network (DenseNet) is applied to improve the model's ability to extract local features of ECG signals, and bidirectional long short-term memory network (BiLSTM) is introduced to improve the performance of the model in extracting time series features of ECG signals; Finally, weighted cross entropy loss function is used to alleviate the class imbalance of arrhythmia, and Softmax function is applied to achieve 4 classifications of arrhythmia. Experiments based on MIT-BIH arrhythmia database show that under the intra-patient paradigm, training time for each epoch, overall accuracy, F 1 and specificity are 42 s, 99.44%, 95.89% and 99.32%, respectively; Under the inter-patient paradigm, training time for each epoch, overall accuracy, F 1 and specificity are 23 s, 92.37%, 63.49% and 94.51%, respectively. Compared with other classification models, the model proposed in this paper has a good classification effect and is expected to be used in clinical auxiliary diagnosis.

An efficient and scalable approach is described for the total synthesis of the marine natural product Et-743 and its derivative lubinectedin, which are valuable antitumor compounds. The method delivers 1.6 % overall yield in 26 total steps from Cbz-protected (S)-tyrosine. It features the use of a common advanced intermediate to create the right and left parts of these compounds, and a light-mediated remote C-H bond activation to assemble a benzo[1,3]dioxole-containing intermediate.

Additional file 1. The list of top 200 candidate genes.

Internal stress in basin insulators of gas-insulated metal-enclosed switchgear (GIS) can lead to cracks, which affects the safe operation of these apparatuses. In this research, we proposed a subsurface internal stress measurement method for GIS epoxy composites. This method is based on an ultrasonic longitudinal critically refracted (LCR) wave technique. In this study, some epoxy composite specimens were synthesized with similar materials and manufacturing processes to those of 252 kV GIS basin insulators. An ultrasonic stress measurement system that utilized the LCR wave technique was set-up to investigate the relationship between stress and LCR wave propagation time, as well as to measure the compressive stress of the epoxy specimen within 0–50 MPa. The results show that LCR wave propagation time linearly decreased when stress increased in the subsurface zone and the acoustoelastic coefficient was −4.95. We found the relative errors of stress measurements to be less than 13%.

Situations of internal stress in basin insulators inside gas-insulated metal-enclosed switchgear (GIS) can lead to cracks, which can influence the safety and stability of apparatus. However, there is currently no research on internal stress measurements for composites of GIS basin insulators, and only measurements for surface stress. In this paper, an internal stress measurement method for GIS epoxy composite is proposed using an ultrasonic longitudinal through-transmission technique based on the acoustoelastic effect. An internal stress measurement system is developed to investigate the relationship between the uniaxial compressive internal stress and the velocity of the ultrasonic wave vertical to the stress in epoxy composite within a range of 0&ndash, 70 MPa, and to calculate the acoustoelastic coefficient of epoxy composite. The effects of system delay are eliminated in measuring the propagation time. Some epoxy composite cuboid specimens with similar materials and using a manufacturing process similar to those of 252&nbsp, kV GIS basin insulators are synthesized, and the uniformity of the internal stress in cuboid specimens is verified by finite element simulation. The results reveal a linear increase of the ultrasonic longitudinal wave velocity with increasing stress. It has been shown that the average acoustoelastic coefficient of GIS epoxy composites, using the longitudinal waves vertical to the stress, is 4.556 &times, 10&minus, 5&nbsp, /MPa. Additionally, the absolute errors of the internal stress measurements are less than 12.397 MPa. This research shows that the ultrasonic method based on the acoustoelastic effect for measuring the internal stress in GIS epoxy composites is feasible.

Voids or cracks in basin insulators inside a GIS (gas-insulated metal-enclosed switchgear) could trigger partial discharges or surface flashover under electrical stresses, threatening safe GIS operation. For this paper, some epoxy composite specimens were made from similar materials and manufacturing processes to make 252 kV GIS basin insulators. Some voids with different diameters or cracks with different diameters and orientations were artificially made in the specimens with different thicknesses. An ultrasonic pulse-echo system was set up, and ultrasonic tests were carried out on the specimens with voids or cracks. A method to calculate the depth of a defect was proposed by the propagation time of defect reflected waves. The results showed that a depth of 50 mm, a diameter φ of 2 mm void, and a diameter φ of 1 mm crack in epoxy composite insulation were detected by the ultrasonic system using a 1 MHz transducer.

Lin Zhou,1,* Weiming He,2,* Wenjun Wang,1 Daoping Zhou31Department of Medical Record and Statistics, Anhui No.2 Provincial People’s Hospital, Hefei, Anhui, 230041, People’s Republic of China; 2Department of Public Health, Guangdong Medical University, Zhanjiang, Guangdong 524023, People’s Republic of China; 3Department of Oncology, Anhui No.2 Provincial People’s Hospital, Hefei, Anhui, 230041, People’s Republic of China*These authors contributed equally to this workBackground: Prostate cancer (PCa), one of the most common cancers in men, accounts for nearly 20% of adult malignant neoplasms. Omentin-1 is synthesized in visceral adipose tissue and its concentration in plasma changes with cancers. However, the association between omentin-1 and PCa was rarely studied. Thus, we investigated the plasma omentin-1 levels in PCa patients in Chinese population.Materials and methods: Ninety cases of PCa and 90 matched healthy controls were enrolled in this study. We used ELISA technique to determine the concentration of omentin-1.Results: The concentration of omentin-1 was higher in patients with PCa compared to controls (P

Based on the D-H notation, kinematics model and inverse kinematics model of 6R industrial robots are established. Using graphical method, the boundary curve equations of the 6R industrial robot workspace are obtained. Based on the prescribed workspace, the D-H parameter optimization method of 6R industrial robots is proposed. Using the genetic algorithm to determine the structural dimensions of a 6R robot, we make sure that its workspace can exactly contain the prescribed workspace. This method can be used to reduce the overall size of the robot, save materials and reduce the power consumption of the robot during its work time.

Global temperatures are now predicted to be 1—6 ℃ warmer than today by the year 2100.Environmental warming is likely to have significant effects on plant carbon relations,particularly through its effects on photosynthesis and respiration.In terrestrial environments,the nighttime daily minimum air temperatures in recent decades have increased more than the daytime maximum air temperatures.Understanding how plants respond to differential day/night warming may help scientists to predict the responses of plants to global warming.Most published studies of the effects of warming on plant growth have focused on either dominant species or invasive species.Little attention has been paid to endangered plants,but understanding how such species adapt in the context of global warming may be critical to their survival.Sinocalycanthus chinensis is an endangered plant belonging to the family Calycanthaceae.Here,we analyzed the effects of differential simulated day/night warming on the photosynthesis characteristics and chlorophyll fluorescence parameters of S.chinensis seedlings.Three different simulated day/night warming treatments were included in the experiment: 1) warming of 2 ℃ above ambient temperature at daytime;2) warming of 2 ℃ at nighttime;3) warming of 2 ℃ at both day-and nighttime.Seedlings exposed to ambient temperatures without warming were used as the control treatment.In three seasons,the net photosynthetic rate(Anet) and the maximum net photosynthetic rate(Amax) in all three warming treatments were higher than in the control,indicating that simulated warming could increase the photosynthetic ability ofS.chinensis.Simulated warming also increased the daily mean stomatal conductance(Gs) and the dark respiration rate(Rd),while it decreased the daily mean intercellular concentrations of CO2.In three different seasons,Anet and Amax ofS.chinensis seedlings subjected to daytime warming were the highest,indicating that S.chinensis seedlings with daytime warming had the highest photosynthetic ability.The apparent quantum yield,light saturation point,and relative chlorophyll content of S.chinensis seedlings subjected to daytime warming were significantly higher than plants in the other warming treatments and the control.Simulated warming significantly decreased the Fv/Fm value of S.chinensis seedlings.During the period from 12:00 pm to 2:00 pm,the Fv/Fm value of S.chinensis seedlings treated with daytime warming was the highest,followed by those treated with nighttime warming and all-day warming,with significant statistical differences among the treatments.In conclusion,the different warming treatments increased the photosynthetic ability of S.chinensis to different degrees.The maximum values of Anet and Amax of S.chinensis seedlings subjected to daytime warming suggested that the highest photosynthetic ability of S.chinensis seedlings occurred under daytime warming.This might be due to the increase in relative chlorophyll content,the enhancement of the light adaptation ability,and the lower levels of light stress in the leaves of S.chinensis seedlings under daytime warming.The results of this study suggested that warming conditions in the future will improve the photosynthetic physiological activity and promote the growth of S.chinensis,perhaps benefiting this endangered species.

In this paper, a method of choosing mixture medium in two-cell stimulated Brillouin scattering (SBS) system to improve the system performance is proposed. The Brillouin frequency shift (BFS) of mixture medium varies with the mixing ratio and thus the difference of the BFS between the two cells can be eliminated. The two-cell SBS system with acetone (C3H6O) in its generator cell and mixture liquid of CCl4/C2Cl4 in its amplifier cell is investigated. The C3H6O has a high optical breakdown threshold and the mixture liquid of CCl4/C2Cl4 has a small absorption coefficient and the same BFS as that of C3H6O when the volume fraction of CCl4 is 4%. Compared with two-cell SBS system with the same liquid (C2Cl4) or different liquid (C3H6O and C2Cl4) in generator and amplifier cell, the SBS system with mixture liquid (CCl4/C2Cl4) in amplifier cell and C3H6O in generator cell improves the power-load, energy reflectivity (ER), phase conjugation (PC) fidelity and ER stability.

In this study, from forty different varieties of celery in different regions of China as test material, the scientific character of RAPD technology in the identification of celery cultivars was carried out in the verification and analysis technology. The results show that the RAPD can well distinguish the genetic relationship of celery varieties of far and near, is suitable for the analysis of celery cultivars relationship between simple and ideal DNA molecular marker technology. One of the thirteen bases of different length of primer RAPD technique in the analysis of celery cultivars relationship between definition and the number of bands have the obvious difference, method based identification as celery varieties with different genetic relationship.

This paper introduces the domestic and international situation and development trend of resource conservation, analyzed the current situation, existing problems and strategies for solving problems. for Beijing germplasm of vegetables resources. We should accentuate the consciousness and the important action of resource conservation, germplasm collection on agricultural research and production.

Purple yam (Dioscorea alata L.) belonging to the herbaceous vine plants, dioscorea genus, Dioscorea subject and one kinds of edible plants. It’s Native to tropical Asia, purple yam is plants grown under a suitable short sunshine growth environment, is a kind of thermophilic plants, mainly temperate zone in China's southern provinces. We performed different cultivation methods on Yield and variety comparison test for planting on north area of China. To choicing the different position of the yam block, shuch as the top and the middle block and different weight of harvested. Then average per mu 2600 strains were calculated and counting the per mu yield. The growth of the top position of the yam is better than the middle of plant growth. The yield of the top position is higher than the same weight of tubers of the middle position. The best kind of potato weight should be between 100-150g, so that it can reduce costs, but also have a considerable income.

Based on the limited understanding of the former researchers on RAPD marker, numbers of cultivars of purple yam were utilized to evaluate the application of RAPD in cultivar identification of purple yam. The results showed that RAPD was a stable DNA marker technique, and it could be scientifically and easily used in cultivar identification purple yam. The RAPD fingerprints of purple yam crops, which were derived from primers with different number of nucleotides length, were different in band number, polymorphism and band clarity. Basically, RAPD primers with S1255 can show DNA fingerprint clearly in purple yam for the generation, while RAPD primers with S1255 is more suitable purple yam crops.

Understanding the functional traits and ecological mechanisms associated with successful invasions of alien plants is a key role of the field of invasion ecology. Through literature review and analysis of plant functional traits contributing to successful plant invasions and the demands for functional traits at different invasion stages, we discuss the relationships between the functional traits and invasiveness of alien plants as well as related ecological mechanisms. Functional traits that have been studied in relation to their invasions mainly include seed characters, and morphological, developmental, physiological, clonal and propagation characteristics, as well as genetic variation and plasticity of phenotype. The impacts of these functional traits on invasion success vary from one stage to another. At the introduction stage, plant invasions are mainly affected by seed characters. At the establishment stage, stress-tolerance related physiology and propagation traits exert important influences. At the explosion stage, clonal characters and physiological traits related to competitive ability largely contribute to invasion success. Because plant invasions result from interactions between plant functional traits and environmental features, further studies on plant invasions 570 生 物 多 样 性 Biodiversity Science 第 18 卷 should consider both the effects of invasion stage and specific environmental variables on invasion success.

Pulse compression based on laser-induced optical breakdown in suspension is investigated. The physical mechanism behind it is analyzed theoretically and validated in the Q-switched Nd:YAG laser system. A 12-ns pump pulse is suppressed to 5 ns with good fidelity in the front edge and sharp steepness in the trailing edge. The HT-270, which has a small gain coefficient and absorption coefficient, is used as a solvent, and therefore the disturbance induced by stimulated Brillouin scattering and absorption are minimized and the transmittivity is enhanced.