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In order to solve the problems of complex detection scene, low detection accuracy and high computational complexity of tomato leaf pests and diseases in natural environment, a deep learning algorithm SLP-YOLOv7-tiny was proposed. Firstly, part of the 3×3 convolution Conv2D Convolution in the backbone feature extraction network is changed to distributed migration convolution DSConv2D (2D Depthwise Separable Convolution) to reduce the computing load of the network and speed it up. Less memory usage; Secondly, the parameter-free attention module (SimAM) was integrated into the backbone feature extraction network to enhance the model's ability to effectively extract and integrate features of pests and diseases. Finally, the original YOLOv7-tiny CIOU loss function is replaced with Focal EIOU loss function to accelerate the model convergence and reduce the loss value. The test results show that The overall identification accuracy, recall rate, average accuracy mAP0.5 (the average accuracy when the IOU threshold is 0.5), and mAP0.5 ~ 0.95 (the average accuracy when all values of the IOU threshold are averaged between 0.5 and 0.95) of SLP-YOLOv7-tiny model are 95.9%, 94.6%, and 98, respectively Compared with YOLOv7-tiny before the improvement, they respectively increase by 14.7, 29.2, 20.2 and 30 percentage points. Meanwhile, the calculation amount decreases by 62.6% and the detection speed increases by 13.2%. Compared with YOLOv5n, YOLOv5s, YOLOv5m, YOLOv7, Yolov7-Tiny, Faster-RCNN and SSD target detection models, mAP0.5 improved by 2.0, 1.6, 2.0, 2.2, 20.2, 6.1 and 5.3 percentage points respectively. The computing capacity was only 31.5%, 10.6%, 4.9%, 4.3% and 3.8% of YOLOv5s, YOLOv5m, YOLOv7, father-RCNN and SSD. The results show that SLP-YOLOv7-tiny can accurately and quickly detect tomato leaf diseases and pests, and the model is small, which can provide certain technical support for the development of rapid and accurate detection of tomato leaf diseases and pests.SLP-YOLOv7-tiny can be expected to accurately and rapidly detect the tomato leaf diseases and insect pests. The small model was more conducive to the migration application. A comparison was also performed on the detection performance of different attention mechanisms. The SimAM attention mechanism shared the better screening of effective feature information on the YOLOv7-tiny model. The disease spots were identified to effectively improve the accuracy of the model, compared with the SENet and CBAM attention mechanism. The ablation test was carried out to verified the added module. The high detection accuracy and computational efficiency were suitable for the deployment in the natural environment with the limited computing resources, such as mobile terminals. The visualization of model detection show that the SLP-YOLOv7-tiny model can be used to learn and distinguish the fine features of tomato leaf disease spots. The detection accuracy was also better than that of the YOLOv7-tiny model. Moreover, the SLP-YOLOv7-tiny model can be used to accurately identify the diseases and pests of diseased tomato leaves in the natural shooting environment. The high detection accuracy can be applied for the multiple diseases and pests. The better identification was also obtained for the small features in the similar diseases and pests. The finding can provide the technical support for the rapid and accurate detection of tomato leaf diseases and insect pests. [ABSTRACT FROM AUTHOR]

To reveal the effects of nicotinamide phosphoribosyltransferase (Nampt) and high glucose and high insulin (HG+HI) microenvironment on proliferation and metastasis of human cisplatin-resistant lung cancer cell lines. Human cisplatin resistant cell line A549/DDP was divided into 6 groups (n=6): control group, high glucose and high insulin intervention group (HH, cultured with 30 mmol/L glucose and 500 mU/L insulin for 72 h), sh-NC and sh-Nampt transfected groups (Lipofectamine 2000 was used to transfect sh-NC and sh-Nampt into cells respectively, the transfection time was 48 h), HH intervention sh-NC and sh-Nampt groups (HH+sh-NC and HH+sh-Nampt). Each group had 6 replicates. The transfection efficiency was detected by qRT-PCR. Cell proliferation was detected by MTT method, apoptosis was detected by flow cytometry, cell migration and invasion were detected by Transwell, Nampt mRNA was detected by qRT-PCR, and protein expression of Nampt, Bcl-2, Bax, MMP-2, MMP-9, p-PI3K, PI3K, p-AKT and AKT were detected by Western blot. Compared with control group and sh-NC group, the expression level of Nampt mRNA and protein, relative cell viability, the number of migratory and invasive cells decreased, the rate of apoptosis increased, the expression level of Bcl-2, MMP-2, MMP-9, Nampt, p-PI3K and p-AKT protein decreased, and the expression level of Bax protein increased in sh-Nampt group (P<0.05). Compared with control group and sh-NC group, the expression level of Nampt mRNA and protein, relative cell viability, the number of migratory and invasive cells increased, the expression level of Bcl-2, MMP-2, MMP-9, Nampt, p-PI3K and p-AKT protein increased, and the expression level of Bax protein decreased in HH group and HH+sh-NC group (P<0.05). Compared with HH group and HH+sh-NC group, the expression level of Nampt mRNA and protein, relative cell viability, the number of migratory and invasive cells decreased, the rate of apoptosis increased, the expression level of Bcl-2, MMP-2, MMP-9, Nampt, p-PI3K and p-AKT protein decreased, and the expression level of Bax protein increased in HH+sh-Nampt group(P<0.05). High glucose and high insulin microenvironment may induce proliferation and metastasis of human cisplatin-resistant lung cancer cells by up-regulating Nampt/PI3K/AKT signaling pathway. [ABSTRACT FROM AUTHOR]

Objective To analyze the epidemic characteristics of other infectious diarrhea in Fuyang from 2016 to 2020, and to provide the basis for the formulation of prevention and control measures. Methods Other infectious diarrhea cases reported in Fuyang city from 2016 to 2020 in the "China Disease Prevention and Control Information System" were analyzed using descriptive epidemiological method. Results A total of 47 396 cases of other infectious diarrhea were reported in Fuyang from 2016 to 2020, with an average annual incidence of 117. 17/100 000. There was a statistically significant difference in incidence(X²=1 223.17, P< 0. 01). At its peak in June to August, there were cases reported in 8 counties. The average annual incidence of the top three were Jieshou Country (199.38/100000), Funan County (179.39/100 000) and Yingquan Country (162.97/100 000);The highest incidence was in the under-5 age group, accounting for 21.34% of all casessmale was higher than female(X²=4 961.97, P<0.01), and the male-female ratio was 1. 13:1. About 94.02% of the total number of reported cases are mainly farmers, scattered children and students. Conclusion In recent years, the incidence of other infectious diarrhea in Fuyang city has increased every other year. The prevention and treatment of other infectious diarrhea and health education should be carried out in the period of high incidence for key areas and population groups, while strengthening monitoring. effectively reduce the incidence of other infectious diarrhea. [ABSTRACT FROM AUTHOR]

Vegetable pot seedling transplantation has many advantages, such as high survival rate, promoting crop early maturity and improving land use rate. Mechanized transplanting of vegetable can be divided into semi-automatic transplanting and fully-automatic transplanting. Semi-automatic transplanting is mainly carried out by feeding the seedlings into the seedling transplanter manually, which has low efficiency and high labor intensity, and it is not conducive to field operations. At present, the automatic transplanting machine mainly adopts multiple mechanisms to complete a series of actions such as picking up seedling, conveying and planting, but it has the disadvantages of complex structure, high cost and low efficiency. In order to simplify the structure, the way to complete the transplanting operation with a single mechanism is proposed. However, due to the complicated working trajectory of transplanting vegetable seedling and much posture requirements, the transmission ratio of the mechanism is required to be changed greatly, which resulting in the irregular shape of the non-circular gear section of the single planetary gear is not conducive to processing and affects the transmission performance of the gear. A double-planetary non-circular gears linkage of vegetable pot seedling transplanting mechanism is proposed to solve the problem mentioned above in this paper. The transmission part of transplanting mechanism is composed of planetary gear train mechanism and crank rocker mechanism, The main planetary frame rotates at a uniform speed, through the transmission of internal gears and connecting rods, the unequal transmission of non-circular gear system and the periodic variable-speed swing of crank-rocker mechanism are superimposed, which makes the sub-planetary frame swing with respect to the main planetary frame and the transplanting arm rotate with respect to the sub-planetary frame, thus the transmission ratio needed to realize the complex transplanting trajectory and posture is obtained. Non-uniform B-spline curve is applied to fit the pitch curve of non-circular gear to obtain closed, smooth and continuous pitch curves, and the mathematical model of gear train is established based on coordinate transformation theory. Based on the development platform of Matlab, an optimization program is compiled to analyze the effect of transmission case noncircular gear pitch curve and crank rocker mechanism on the shape of trajectory. Further, the effects of the structure and position parameters of the gears and transplanting arm on the target parameters of the transplanting trajectory are analyzed. According to the requirements of 220 mm planting spacing, 120 mm seedling height and 40 mm deep pot for celery transplantation, a set of sharp beak trajectory that satisfies the requirements of the operation posture of picking up seedling and planting is optimized. The optimizing values are that the length of the picking up seedling trajectory is 33 mm, the distance from the lowest point of the trajectory to the lowest point of the planet carrier is 55 mm, the angle of picking up seedlings is 23°, the angle of change in the process of picking up seedlings is 16°, the angle of planting seedlings is 65°, the whole height of the trajectory is 355 mm, and the height of the buckle of the moving trajectory is 125 mm. A three-dimensional model of the mechanism is built and a virtual simulation is performed based on the optimization result. The results show that the simulated trajectory and velocity of the transplanting mechanism are basically consistent with the theoretical results. The trajectory and postures of the transplanting arm are analyzed by a test bench, industrial camera and image processing software. The results show that the trajectory of seedling-taking and seedling-pushing sections coincides with the simulation trajectory basically and the theoretical data, and the error is within 2 mm, which can meet the requirements of transplanting operation, the transplanting mechanism designed is reasonable and feasible. [ABSTRACT FROM AUTHOR]

The media plays an important role in laboratory opening management. Asymmetric information and poor communication have aggravated the contradiction between supply and demand of equipment，and affected the quality of laboratory opening and students^enthusiasm for creation. Media environment，managers and students^habit determine the choice and use of media. As a mobile office platform，Dingtalk can make the laboratory managers who do not have the capability of technology development complete the design and development of relevant applications. By the platform，a mobile open system is built to achieve totally open in laboratory contents，equipment and management， it is suitable to the changing of student U media behavior in the mobile Internet environment. The applications and practice of the platform in the Media Opening Laboratory of Chongqing University，contain to deploy related equipment booking module， lab reservation module and undergraduate innovative experiment projects submitting module. The platform can also enhance the collaboration efficiency and bring some references for other opening laboratories in the new media era. [ABSTRACT FROM AUTHOR]

For rice seedling transplanting, there are more than 5 kinds of planting patterns in China, including equal row carpet seedling transplanting, wide-narrow row carpet transplanting, equal row pot seedling transplanting, wide-narrow row pot seedling transplanting, and semi-pot seedling transplanting. The zigzag wide-narrow row rice seedlings transplanting is a new method of planting adjacent rows of rice seedling alternately, and distributing wide and narrow rows. This kind of planting method absorbs the merits of traditional equal row pot seedling planting, wide-narrow row carpet seedling planting and zigzag planting. The pattern of zigzag and wide-narrow row pot seedling transplanting can increase the light penetration and ventilation of the paddy-field, which brings some advantages such as reducing the plant diseases and insect pests, increasing lodging resistance ability of rice and improving the rice yield and quality for rice production. In this paper, a variable and differential transplanting mechanism for zigzag wide-narrow row rice pot seedlings was presented. This mechanism consists of 2 major parts that are transmission case and gear case. There are 10 gears, including 2 pairs of noncircular gears, 2 pairs of bevel gears as well as one pair of spur gears, employed to transform one input constant rotational speed into 2 output rotational speeds which are used to drive the noncircular gear case. Based on the non-uniform and spatial transmission of differential gear train, this mechanism can achieve a special figure-eight spatial-shaped trajectory, which can meet the kinematic requirements of zigzag wide-narrow row pot seedling transplanting. In order to obtain closed, smooth and continuous pitch curves, non-uniform B-spline curve was applied to fit the pitch curve of non-circular gear, and the mathematical model of gear train in gear case was established based on coordinate transformation theory. Moreover, the trajectory and attitude requirements of the zigzag wide-narrow row pot seedling transplanting were parameterized into 9 specific kinematics optimization objectives. Based on the development platform of MATLAB GUI, an optimization program was compiled to analyze the effect of transmission case noncircular gear pitch curve and gear case noncircular gear pitch curve on the shape of trajectory. Further, the effects of the structure and position parameters of the gears and transplanting arm on the target parameters of the transplanting trajectory were analyzed. By human-machine interaction, a group of structural parameters including data points of pitch curves meeting the requirements were optimized. Using these parameters, a 3D (three-dimensional) model of the mechanism was built, and virtual simulation was carried out. The simulation trajectory and velocity data of the transplanting arm clip were basically consistent with theoretical results. The parts of the right transplanting mechanism were processed and assembled. The trajectory and attitude of transplanting arm were analyzed by test bench, industrial camera and image processing software. The results were consistent with the theoretical data, which verified the feasibility of the transplanting mechanism and the rationality of the structure. [ABSTRACT FROM AUTHOR]

The lab study for routing and switching technology generally needs the support from a certain number and different types of physical devices and networking environment，but in most cases，teachers and learners dont have the ability to buy the physical devices and to build networking environment. The paper uses Cisco Packet Tracer free software and open source project GNS3 open source software as simulator and implements to give the integrity lab solution for routing and switching technology on the background of campus network in single machine environment + it can provide the network configuration requirements of campus network and the network topology structure. The paper compares and discusses the use process of two kinds of simulator software from three aspects including routers，switches， terminal equipment，and provides the design thought and the configuration reference for otlier comprehensive lab about routing and switching technology in single machine environment [ABSTRACT FROM AUTHOR]

Different from the acoustic microphone, the visual microphone uses high frame rate cameras to restore sound by using sound vibrations to cause subtle differences between frames of surrounding objects. By simulating the positional brightness interleaving neural network of v2, this paper proposed a two-dimensional logarithm-based coordinate-gray interleaving mapping algorithm. The algorithm interleaved and mapped the video frame image matrix with the function construct matrix. The algorithm generated chaotic attractors to preserve and amplify the micro-differences between frames, and constructed the visual microphone sound restoration system based on the algorithm. Simulation experiments show that the visual microphone system can recover the sound signal from the high frame rate video of the bag of chips. Compared with the traditional algorithm, this algorithm reduces the calculation amount by 40%, while maintaining the quality of speech restoration. [ABSTRACT FROM AUTHOR]

Objective To understand the left-behind women's reproductive tract infection (RTI) status and influencing factors in the northeast ecological conservation development area of Chongqing to perfect the epidemiological monitoring and management and provide a scientific basis for the left-behind women's RTI prevention and control. Methods A total of 360 left- behind women and non-left-behind women as the research subjects were randomly extracted from northeast ecological conserva­tion development area of Chongqing from October 2015 to August 2016. The general data, awareness situation of AIDS transmis­sion route, classification and composition of RTI pathogens and relation between RTI with age were performed the statistical anal­ysis by using the reproductive health related questionnaire and laboratory detection. Results Among 360 respondents, the de­tected cases included 8 cases of treponema pallidum infection, 28 cases of Chlamydia trachomatis infection,48 cases of Ureaplas -ma urealyticum infection, 16 cases of gonococcal infection, 16 cases of trichomonal infection and 28 cases of mycotic infection. The awareness rates of transmission through blood transfusion, injection transmission, sexual intercourse transmission, fetal trans­mission of pregnant women, and known AIDS transmission routes such as breast feeding and mosquito bite had no statistical dif­ference between left behind women and non-left-behind women (P>0.05) , while the awareness rate of transmission route of sharing meal at the same table in non-left-behind women was significantly higher than that in left-behind women, the difference was statis­tically significant (P<0.05 ) ; the RTI risk of sexual transmission except for AIDS and non-sexual transmission in left-behind women was significantly higher than that in non-left-behind women with statistically significant difference (P<0.05 ) , moreover mycoplasma infection was more evident; the RTI occurrence risk by sexual transmission and non-sexual transmission had statisti­cal difference between different ages of left-behind women and non-left-behind women (P<0.05 ) , moreover the RTI occurrence rate by sexual transmission was decreased with age increasing, while which by non-sexual transmission was increased with age increasing. Conclusion Strengthening the publicity and education of RTI prevention and treatment and related knowledge on left- behind women, and regular health screening and intervention are conducive to reduce the RTI risk in left-behind women. [ABSTRACT FROM AUTHOR]

Using the daily icing weather phenomenon, the minimum temperature observation data and basic information of 56 national meteorological observatories, the spatial distribution and temporal trends of icing weather phenomenon in Anhui Province in the past 55 years(from 1961 to 2016) were statistically analyzed. The correlations between icing weather phenomenon and latitude, altitude and the minimum temperature were discussed separately. The results showed that the icing weather phenomenon in Anhui Province has obvious regional characteristics in spatial distribution. The number of icing days and the icing period generally showed a gradual decrease from north to south, but a significant increase occurred in high altitude areas due to the mountains in the parts of the south of Yangtze River. The first date of icing occurs the earliest in the northern part of Huaibei and the high-altitude mountainous area in the south of the Yangtze River, but the latest between the south of the Yangtze River and the Huaihe River to the Jiangnan area. However, the distribution of the last date of icing is opposite. There is a clear correlation between the spatial distribution of icing, latitude and altitude, and the absolute values of the correlation coefficient are more than O. 5 and O. 8. In term of time changes, the phenomenon of icing in Anhui Province mainly occurred from November to March of the following year, and concentrated in December to February of the following year. The phenomenon of icing in the past 55a showed a clear trend that both the number of icing days and the icing period decreased, and the first date of icing and the last date of icing were delayed and advanced respectively. The trend of the icing weather phenomenon from south to north is generally consistent, but there are also certain regional differences. The results showed that there were mutations in the number of icing days, icing period, the first date of icing and the last date of icing. The mutation time was 1988, 1994, 2000 and 1991 respectively. The distribution and change of icing weather phenomenon are also significantly correlated with the minimum temperature with the absolute values of correlation coefficient above O. 7. With the increase of the minimum temperature, the number of icing days per month shows a decreasing trend, and the monthly distribution of icing days gradually concentrate towards January and December. [ABSTRACT FROM AUTHOR]

Based on the data of more than 40 wells( 12 drainage wells) in East Yunnan-Western Guizhou area,the influencing factors of drainage dynamic in Enhong, Laochang and Tucheng blocks are discussed through the ex-traction of drainage dynamic typical indexes of CBM wells and the comprehensive analysis of geological and engineering factors, combined with numerical simulation and the primary drainage rate optimization steps are finally put forward. The results show that there is a great difference in the drainage dynamic of CBM wells in the study area. The producing resource abundance and permeability determine the gas production capability of CBM wells as basic factors. The higher the producing resource abundance and the permeability are, the higher gas production is. Meanwhile, the reservoirs with coal body structure Type 1 and II have a higher gas production compared to that with coal body structure Type III. The primary drainage rate is the key controlling factor of drainage dynamics of CBM wells. When the primary drainage rate is relatively high, even with the permeability and the producing resource abundance being high, the gas production is still relatively low. Controlling the primary drainage rate has two meanings;one is to slow down the reduction of absolute permeability( stress-sensitive), and the other is to delay the occurrence of two-phase flow, both having objective to extend the depression cone to maximum. Based on the above understanding, it is pointed out that slow drainage should be key in the study area. A low rate-ladder type pressure reduction, during primary drainage, is proposed. This pressure reduction regime has a certain practical significance for co-production from multiple-coalbeds in East Yunnan-Western Guizhou area. [ABSTRACT FROM AUTHOR]

The ray radiation and electromagnetic scattering of the sphere models in the ballistic range are measured to investigate the effects of hypervelocity vehicle and flow field on the target detection and recognition. The models are launched from a two-stage light gas gun. The models are the spheres with the diameter of 15 mm, which are made of Al2O3. The velocity ranges from 4.2 km/s to 6.1 km/s, and the target chamber pressure ranges from 2.0 kPa to 15.4 kPa. The intensities of ultraviolet radiation (254 nm and 365 nm) and visible radiation (430 nm) of the models are measured by the photomultiplier detectors, respectively. The intensities of infrared radiation (3-5 μm and 8-12 μm) of the models are measured by using InSb detectors. The radar cross section (RCS) of the full targets is measured by the monostatic radar system working at X waveband, of which the visual angle between the main beam and the flight direction is 40°. The results show that the ray radiation intensities of the models and flow field and the electromagnetic scattering characteristics depend on the flight speeds of the models and the chamber pressure. The ultraviolet radiation intensity is the same as their visible light radiation intensity. The difference of radiation intensity between 3-5 μm and 8-12 μm is within one order of magnitude. The ultraviolet radiation and visible radiation mainly come from the shock wave radiation, which do not present in the wake radiation at all. The intensity of infrared radiation of the wake in the range of 3-5 μm is higher and its duration is longer compared to that of 8-12 μm. The electromagnetic scattering energy mainly comes from the regions of the models surrounded by the flow field when the flight speed is lower, and the electromagnetic scattering energy of the wake is markedly strengthened when the flight speed is higher. The electromagnetic scattering energy mainly comes from the regions of the models surrounded by flow fields and wakes when the flight speed is high. The total RCS of wake is about one order of magnitude larger than that of the model surrounded by flow fields under certain conditions. [ABSTRACT FROM AUTHOR]

The purpose of the new technology of the network engineering specialty is to expand the students' perspective, and make the students understand the frontier technology and the development trend in this field. In view of the problems of current teaching of new technology-the cloud computing and the Internet of things, students are lack of perceptual knowledge, teaching content is empty and boring. To effectively address the above issues, the experiment teaching environment, called smart home system, is designed and constructed. Students learn through perceptual knowledge, enhance ability of programming and secondary development. The experiment achieves the purpose of improving teachers' teaching and students' learning efficiency, and meets the needs of engineering personnel training goals and needs. [ABSTRACT FROM AUTHOR]