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The cocoa tree is prone to diverse diseases such as stem borer, stem canker, swollen shot, and root rot disease which impedes high yield. Early disease detection is a critical component of diverse management processes that are implemented throughout the life cycle of cocoa plants. Consequently, several studies on the application of detection techniques to recognize diseases have been proposed by several researchers. This study proposes the YOLOv5m network for cocoa tree disease detection. The development of cocoa disease detection systems will aid farmers in early identification prompt response, and efficient management of related cocoa tree diseases which will ultimately increase yield and sustainability. To improve the performance of the YOLOv5m network, a Swin Transformer (Swin-T) was added to the backbone network to improve cocoa tree disease detection accuracy. By obtaining global information, the K-means++ algorithm was added to modify the choice of initial clustering locations, and Efficient Intersection over Union Loss (EIoU) was used as a bounding box regression loss function to speed up the bounding box regression rate, resulting in higher precision of the YOLOv5m network. The experimental assessment outcome of this study showed that the proposed method YOLOv5m (Swin-T, K-means++, EIoU) achieved 96% precision, mAP of 92%, and recall of 94%. Compared to the original YOLOv5m, precision improved by 5%, mAP improved by 6%, and recall by 5%. Comparing the proposed method to the conventional YOLOv5m, the latter showed improved performance and better accuracy with a high detection speed and compactness. This improvement offers a useful and effective method for detecting diseases related to cocoa trees.

During the lightning spectral observation, the spectral intensity is significantly reduced due to instrumental factors and other factors. The spectral intensity attenuation significantly affects the accuracy of temperature calculations. Temperature, as a fundamental parameter, is inextricably linked to other parameters within the lightning discharge channel, and accurate determination of the plasma temperature is crucial for gaining insights into the dynamic and physical processes of the discharge. Up to now, there have been no detailed and definitive reports on the influence of instrumental response on tall building lightning spectroscopy and temperature diagnostics.Based on the spectral analysis of a lightning return stroke channel spectrum, the spectral is corrected by accounting for the instrumental response. Then, the spectral structure and line intensities before and after correction are compared and analyzed. Nitrogen ionized (NII) lines in the visible region and neutral oxygen (OI) lines in the near-infrared region are selected for temperature calculations using the multi-line method. The influence of spectral correction on the temperature analysis of the tall building lightning return stroke channel is investigated. Results show that after correction, the intensity of spectral lines is significantly enhanced. In particular, the spectral line structure in the visible region changes significantly, while the spectral line structure in the near-infrared region changes little. The continuum radiation in the visible region of the corrected tall building lightning spectrum is significantly enhanced, which is different from the results of natural cloud-to-ground lightning spectra after considering the instrumental response correction. Due to the significant enhancement of the continuum radiation intensity in the visible region resulting from the spectral correction, the continuum radiation intensity should be subtracted when using NII lines in the visible region to calculate the tall building lightning temperature. In this case, the coefficient of fitted line and the calculation accuracy increases, while the average temperature decreases by 4660 K compared to that before correction. Conversely, since the original continuum radiation intensity of tall building lightning spectra in the near-infrared region is relatively low, the spectral correction has little effect on the continuum spectrum intensity. Therefore, after spectral correction, when using OI lines in the near-infrared region to calculate the temperature, the determination coefficient of the linear fitting increases, resulting in improved fitting performance and an increase of 1540 K in the average temperature.

Pelvic exenteration is often required for primary rectal cancer beyond total mesorectal excision (PRC-bTME) and locally recurrent rectal cancer (LRRC). Some patients with radical resection can achieve long-term survival, but they need to face risks, such as huge surgical trauma, serious perioperative complications, permanent loss of organ function and decline in quality of life. Preoperative evaluation of PRC-bTME and LRRC should emphasize multidisciplinary collaboration and develop individualized diagnosis and treatment strategies. The principles of function preservation and risk-benefit balance in surgery oncology should be followed, and R0 resection should be emphasized. Perioperative complications, surgical trauma and organ function loss should be minimized to achieve the best quality control and balance point. This consensus was formulated by the Colorectal Cancer Committee of the Chinese Medical Doctor Association and the Gastrointestinal Surgery Committee of China International Exchange and Promotive Association for Medical and Health Care. The draft was formed based on the summary of domestic and foreign research progress and expert experience. After discussion, review and modification by experts, an anonymous voting was conducted for each major opinion, and in-depth verification was carried out according to the principles of evidence-based medicine. Finally, the Chinese expert consensus on the pelvic exenteration with primary rectal cancer beyond total mesorectal excision planes and locally recurrent rectal cancer (2023 edition) was formed. This consensus mainly summarizes the indications and contraindications of pelvic exenteration (PE) for PRC-bTME and LRRC, preoperative diagnosis and evaluation, perioperative treatment, as well as the resection scope, surgical methods, reconstruction of related organs, safety and complications of PE, postoperative follow-up and other issues, in order to provide guidance for PE in patients with PRC-bTME and LRRC.

To investigate the impact of goal-directed fluid therapy (GDFT) on postoperative cognitive dysfunction (POCD) in elderly patients with colorectal cancer, we conducted a randomized controlled trial. Eighty elderly patients who underwent elective laparoscopic radical resection of colorectal cancer were randomly assigned to either the GDFT group or the conventional fluid therapy group. The primary outcome was the incidence of POCD during the initial 7 postoperative days, while secondary outcomes included inflammatory marker levels such as interleukin-6 (IL-6) and S100β protein, hemodynamics, level of lactic acid, postoperative functional recovery, and complications. Among 88 randomized patients, 80 were evaluable for the primary outcome. The incidence of POCD was significantly lower in the GDFT group (15.0%) compared to the conventional fluid therapy group (30.0%), with the highest occurrence observed on day 3 postoperatively in both groups (P < 0.05). IL-6 and S100β concentrations were consistently lower in the GDFT group than in the conventional fluid therapy group at the corresponding time points (P < 0.05). The GDFT group exhibited more stable perioperative hemodynamics and lower lactate levels (P < 0.05). Moreover, patients in the GDFT group exhibited better postoperative functional recovery indicators and a lower incidence of postoperative complications (P < 0.05). In summary, GDFT appears to reduce the incidence of early POCD, accelerate postoperative recovery, and enhance overall prognosis.

Abstract The development of advanced materials capable of autonomous self-healing and mechanical stimulus sensing in aquatic environments holds great promise for applications in underwater soft electronics, underwater robotics, and water-resistant human-machine interfaces. However, achieving superior autonomous self-healing properties and effective sensing simultaneously in an aquatic environment is rarely feasible. Here, we present an ultrafast underwater molecularly engineered self-healing piezo-ionic elastomer inspired by the cephalopod’s suckers, which possess self-healing properties and mechanosensitive ion channels. Through strategic engineering of hydrophobic C–F groups, hydrolytic boronate ester bonds, and ions, the material achieves outstanding self-healing efficiencies, with speeds of 94.5% (9.1 µm/min) in air and 89.6% (13.3 µm/min) underwater, coupled with remarkable pressure sensitivity (18.1 kPa–1) for sensing performance. Furthermore, integration of this mechanosensitive device into an underwater submarine for signal transmission and light emitting diode modulation demonstrates its potential for underwater robotics and smarter human-machine interactions.

Improving the heat resistance of bio-based and biodegradable polyesters is of great significance to extend their applications. Herein, N,N’-trans-1,4-cyclohexane-bis(pyrrolidone-4-methyl carboxylate) (T-CBPMC) was prepared through efficient Michael-addition reaction between dimethyl itaconate and trans-1,4-cyclohexanediamine. The obtained T-CBPMC was copolymerized into aliphatic poly(butylene succinate) (PBS), and a series of PBSPs copolymers with T-CBPMC (BP) molar percentages between 41−80 mol % and weight average molecular weight (Mw) values ranging between 5.77*104 and 6.67*104 g/mol were prepared. BP units efficiently facilitated the melting temperature (203-251 °C) and isothermal-crystallization rate (t1/2 < 20 s) of PBSPs, endowing the highest heat resistance among commercial biodegradable polyesters, which helps maintain stable in pasteurization, high-temperature disinfection, and microwave environments. Moreover, these copolymers displayed remarkable mechanical, gas barrier properties and degradability. PBSP40-PBSP60 obtained high elastic modulus (335–872 MPa) and tensile strength (24.7–31.5 MPa), and good toughness simultaneously. Multiple-ring structures and large steric hindrance of BP units resulted in superior O2 barrier performance than that of non-degradable PET films. Importantly, the PBSP copolyesters showed obvious degradation in water environments and relatively better enzymatic degradation. It was interesting to find that even with 70 % of the BP units, the PBSP copolyesters still retained hydrolysis ability. The resulting PBSP copolyesters open the way for alternative candidates of biodegradable packaging materials with rapid crystallization, high heat-resistance and gas barrier.

Channel current is an important parameter of the lightning discharge, but it's difficult to be directly measured due to the randomness and instantaneity of the natural lightning. The channel luminosity, however, is relatively easier to obtain. If there is a definite relationship between channel current and luminosity, the channel current can be estimated based on its luminosity. The correlation between the current and luminosity of lightning channel can be obtained through artificially triggered lightning experiments, during which the channel current can be directly measured and close-range optical observations of the lightning channel can be carried out.Base on observations of an artificially triggered lightning obtained at the Field Experiment Base on Lightning Sciences, China Meteorological Administration (CMA_FEBLS) in 2022, characteristic parameters of the channel-base current, the luminosity of the metal-vaporized channel, and their correlation are analyzed. The spatial movement of the metal-vaporized channel during the multiple return stroke processes is distinguished using still image with high spatial resolution. Combined with the high-speed video camera images and the channel current data, the correlation between the luminosity of the metal-vaporized channel and the channel current in the process of return strokes, and M components are studied. The results show that compared with the peak current, its squared value has stronger correlation with the peak luminosity for 13 return strokes. For the return stroke followed by a long continuing current, as well as the return stroke decay stage, both the current and M components superimposed on it show good linear correlations with the channel luminosity, with correlation coefficients of 0.981 and 0.988, respectively. However, the slope values of correlation fitting lines for the channel current versus the channel luminosity of the return stroke decay stage and the subsequent continuing current are obviously different. For M components superimposed on the long continuing current, a time delay for the peak luminosity relative to the peak current is revealed, and it is found that a smaller pulse peak current corresponds to a larger delay time.

The tomato crop is more susceptible to disease than any other vegetable, and it can be infected with over 200 diseases caused by different pathogens worldwide. Tomato plant diseases have become a challenge to food security globally. Currently, diagnosing and preventing tomato plant diseases is a challenge due to the lack of essential methods or tools. The traditional techniques of detecting plant disease are arduous and error-prone. Utilizing precise or automatic detection methods in spotting early plant disease can improve the quality of food production and reduce adverse effects. Deep learning has significantly increased the recognition accuracy of image classification and object detection systems in recent years. In this study, a 15-layer convolutional neural network is proposed as the backbone for single shot detector (SSD) to improve the detection of healthy, and three classes of tomato fruit diseases. The proposed model performance is compared with ResNet-50, AlexNet, VGG 16, and VGG19 as the backbone for Single shot detector. The findings of the experiment showed that the proposed CNN-SDD achieved 98.87% higher detection accuracy, which outperformed state-of-the-art models.

Tall object not only has a high probability of being struck by downward lightning, but also is easy to trigger upward lightning. Comparing with 2D optical observation, reconstructed 3D observation by dual-station optical observation can better reflect the real characteristics of the lightning channel. Based on the synchronous dual-station optical observations from the Tall-Object Lightning Observatory in Guangzhou (TOLOG), an upward lightning triggered by a nearby positive cloud-to-ground (CG) flash at Guangzhou Tower is investigated, and 2D and 3D development characteristics of the upward leader are compared.The result shows that the length of 3D channel is 5.4 km, which is 1.5 times of 2D channel. 3D channel is developed at a height of more than 4.6 km in the vertical direction and about 800 m in the horizontal direction. 2D speed ranges from 1.8×104 to 4.5×105 m·s-1, with an average of 1.8×105 m·s-1. 3D speed ranges from 3.8×104 to 7.2×105 m·s-1, with an average value of 2.8×105 m·s-1. Within 10 ms after the leader initiation, 3D and 2D speeds show roughly the same trend. After 10 ms, 2D rate decreases significantly and changes little over time, while 3D speed shows an obvious irregular fluctuation with time. The ratio of 3D speed and 2D speed ranges from 1 to 4.7, with an average of 1.5. The ratio remains stable at 1-2 for the first 10 ms after leader initiation and then shows irregular fluctuations with time. In fact, due to the change of horizontal development direction of the channel 10 ms after the leader initiation, the distance between the channel and the station-1 increases rapidly, leading to increasing speed difference between 3D and 2D observations. The cause for the fluctuation of 3D speed and 2D speed ratio is that the angle between the development direction of the channel and the sight direction of the observation station changes greatly. The results of 2D and 3D vary greatly at a certain stage of upward leader development, which further proves the importance of analyzing 3D development characteristics of lightning.

The abundance of digital images has been facilitated by smartphones and inexpensive storage. Digital forensic investigation requires the processing of tons of digital images collected on devices to either identify or validate the device's user or to ascertain whether the operator has any connections to the case that would be of interest. Examining and evaluating heterogeneous activity presents several difficulties, including variability, complex interaction across information, and volume. Digital forensics processes are said to need the inspection and analysis stages. This research presents a hybrid optimization of the Grey Wolf and artificial bee colony (GW-ABC) optimization with deep learning model Convolutional Neural Network (CNN) i.e., GW-ABC-CNN, and the developed framework is integrated as a module for Autopsy software. The main objective of this research is to detect the heterogeneous activity of humans from the Heterogeneous Human Activity Recognition (HHAR) database. The developed model is integrated into the data-source ingest module; in this module, pre-processing, feature extraction, and detection process is performed. Moreover, in the pre-processing stage, the Min-Max normalization method is used and the required frequency and time features are extracted using the GW-ABC method. In addition, CNN is used to detect heterogeneous activity; this detection process is performed by four layers. Finally, the effectiveness of the developed model is assessed, and the outcomes of using the GW-ABC-CNN paradigm were compared to those of other strategies to evaluate the model's effectiveness.

The concept of digitalization and intelligence is constantly emerging with the rapid development of information technology, and the in-depth integration of digital intelligence empowerment and teacher education development has garnered significant attention. In this paper, we first examine the stage of teacher development under digital empowerment, tracing the path of teacher education development. We then construct the digital and intelligent TPACK model, as well as the model of teacher education development ability. Subsequently, we adopt a BP neural network to evaluate teacher education development and optimize it using a genetic algorithm. After testing the model, we develop a teacher education development evaluation system based on the GA-BP algorithm, which we then apply and analyze. This paper’s optimized model reduced absolute and relative errors by 418.281 and 3.53%, respectively, compared to the traditional model, and improved the overall goodness of fit by 0.0144. Following the implementation of the system in this paper, the teacher assessment analysis revealed an average teaching ability score of 89.75 for teachers majoring in Japanese foreign language, and 90.26 for those majoring in English foreign language. Notably, the average level of English foreign language majors and their various dimension levels were both higher. Secondly, foreign language teachers with two years of training have an average teaching ability score of 91.32, which is 5.07 points higher than those with only one year of training. It proves the effectiveness of the practical application of this system, and this paper also provides suggestions for the development of teacher education by both teachers and schools, which is of practical significance for the optimization and improvement of foreign language teachers’ education in colleges and universities.

This paper explores the innovative path of news dissemination based on multivariate data chain network, through the design and implementation of a multivariate data chain integrated planning system, to improve the transmission efficiency and accessibility of the data chain network, and then optimize the effect of news dissemination. The study designs a multivariate data chain integrated planning system, considering the constraints of delay and transmission, and uses Poisson distribution and queuing theory to analyze the access delay of the data chain. It is found that the access delay can be effectively reduced by controlling the generation and transmission process of data packets. Secondly, the C-RTT algorithm is proposed to optimize the synchronous time slot allocation in Link16 network, which is experimentally demonstrated to improve the time slot utilization by 1.64% to 6.57% and significantly increase the network capacity. Further, the multivariate datalink dissemination model outperforms the traditional news dissemination method regarding news content perception, environmental awareness, news reliability, and environmental behavioral intention. The application of multivariate data chain network has significant advantages in news dissemination and has substantial impacts on the development of news industry.

Objective: To use lactic acid bacteria to ferment salt-free sauerkraut. Methods: By considering the fermentation characteristics and bacterial inhibition capacity of the strains, lactic acid bacteria with high acid production capacity and bacterial inhibition capacity were selected to make a mixed ferment. Then, the fermentation process was optimized using single-factor tests and response surface tests. Results: Lactobacillus plantarum and Lactobacillus acidophilus were selected as the fermenting strains with high growth activity, acid production capacity and bacterial inhibition capacity, and fermented at 30 ℃. The colour and odour of the sauerkraut prepared under this process condition was good and the organoleptic quality was optimal. Conclusion: Fermentation of sauerkraut with lactic acid bacteria under salt-free conditionsis the most effective means of controlling the fermentation process and optimizing product quality, ensuring stable fermentation and high quality sauerkraut.

Our pre-investigation has revealed that long non-coding RNA (LncRNA) AL137789.1 has the potential to predict the survival of patients with pancreatic carcinoma (PCa). Accordingly, the mechanism underlying the implication of AL137789.1 in PCa is covered in the current study. The non-tumor and paired tumor tissues were collected. Kaplan–Meier curve was employed to estimate the survival of PCa patients with high or low expression of AL137789.1. The proliferation, migration, invasion, and cell cycle of PCa cells were determined, and the cytotoxicity of CD8+ T cells was evaluated as well. Levels of AL137789.1, E-cadherin, N-cadherin, and Vimentin were quantified. According to the experimental results, AL137789.1 was highly expressed in PCa and related to a poor prognosis of patients. Overexpressed AL137789.1 enhanced the proliferation, migration, and invasion of PCa cells, increased the cell population at G2/M and S phases yet decreased that in G0/G1 phase, and diminished the cytotoxicity of CD8+ T cells. Also, overexpressed AL137789.1 elevated levels of N-cadherin and Vimentin, while lessening E-cadherin levels. However, the silencing of AL137789.1 produced contrary effects. Collectively, lncRNA AL137789.1 plays a tumor-promotive role in PCa by enhancing the progression and immune escape.

Sensing properties of the human skin are inspiring for the design of stretchable iontronics but achieving self-healing properties, elasticity and effective control of ion dynamics at the same time is challenging. Here, the Authors report a Cl-functionalized iontronic pressure sensitive material and realize good self-healing properties and mechanosensitive piezo-ionic dynamics.

We first assemble a full set of the Boltzmann Equation in Diffusion Approximation (BEDA) for studying thermalization/hydrodynamization and quark production in out of equilibrium systems. We then discuss thermalization and the production of three flavors of massless quarks in spatially homogeneous systems initially filled only with gluons. A complete parametric understanding for thermalization and quark production is obtained for both initially very dense or dilute systems, which are complemented by detailed numerical simulations. For initial distributions more relevant for heavy-ion collisions, the complete thermal equilibration is found to be significantly delayed by considering quark production.

Objective Bilateral medial medullary infarction (MMI) is prone to misdiagnosis. This study summarizes the clinical characteristics of MMI, in order to provide reference to clinicians. Methods and Results The clinical data of the 3 patients with acute bilateral MMI treated in Ruijin Hospital North Campus affiliated to Shanghai Jiaotong University School of Medicine from January 2017 to January 2022 were collected. All 3 patients had acute onset, one case had acute myelitis⁃like manifestations (rapidly progressive quadriplegia), one case had intractable hiccup, and the other one had unilateral limb numbness and fatigue as the first manifestation, accompanied by hypoglossal palsy. The head MRI showed acute bilateral MMI (one case without acute lesions on early MRI). Two cases were misdiagnosed because of either presenting lower motor neuron damage signs or having atypical symptoms. All patients improved after antithrombotic therapy for acute cerebral infarction. Conclusions The clinical manifestations of acute bilateral MMI are diverse, and it's easy to be misdiagnosed in the early stage. The diagnosis is mainly based on clinical manifestations and head MRI, which requires early recognition and timely antithrombotic treatment for acute cerebral infarction. The main distinguishing points are whether there are risk factors for stroke, upper motor neuron damage signs, and the treatment was effective.

Artificially triggered lightning refers to the lightning that is artificially triggered to the ground under appropriate thunderstorm conditions. The location of artificially triggered lightning can be determined; the occurring time can be precisely stamped, and the channel-base current can be measured directly. Therefore, it's one of the effective methods to evaluate the performance of lightning location system (LLS). From the observations of artificially triggered lightning experiment conducted at the Field Experiment Base on Lightning Sciences, China Meteorological Administration from 2014 to 2019, 50 lightning flashes are selected to evaluate and analyze the performance characteristics of Guangdong-Hongkong-Macau Lightning Location System (GHMLLS).The results show that the lightning detection efficiency and stroke detection efficiency are about 96% (48/50) and 88% (233/265), respectively. The arithmetic mean, geometric mean and median values of location error are 279 m, 193 m and 202 m, respectively. The results show that there is a systematic deviation to the southwest in GHMLLS observations around the triggered lightning experiment site, which is about 170 m to the west and 50 m to the south. After correction, the arithmetic mean, geometric mean and median values of location error are reduced to 198 m, 108 m and 103 m, respectively. The linear fitting result with intercept of 0 shows that the LLS-inferred peak current of GHMLLS is about 65% of the direct measurement value of the channel-base current. Meanwhile, the arithmetic mean (median) value of the LLS-inferred peak current error is -37% (-36%). However, there is a strong positive correlation and the correlation coefficient is 0.93. The arithmetic mean (median) value of the absolute value of the LLS-inferred peak current error is reduced to 15% (12%) when the ratio of 65% is used to correct them. Among 233 return strokes of triggered lightning flashes, 16 return strokes are mistakenly classified as intra-cloud lightning, so the return stroke classification accuracy of GHMLLS is 93%. The peak currents of these mistakenly classified return strokes are lower, the stations available for locating are fewer, and the errors of location and LLS-inferred peak current are larger.In conclusion, GHMLLS have good detection efficiency and location accuracy. The return stroke classification accuracy of GHMLLS is at a high level as well. Nevertheless, there is an obvious systematic deviation in the LLS-inferred peak current of GHMLLS. In order to obtain more reliable analysis results, it's recommended to divide it by 0.65 when using the LLS-inferred peak current of GHMLLS.

Sodium alginate embedding method and chitosan crosslinking method were used to immobilize α -galactosidase from Clitocybe squamulosa. The optimum pH, pH stability, optimum temperature, temperature stability, storage time of immobilized enzyme and free enzyme were compared. The hydrolysis on oligosaccharides in soymilk and operational stability of the two immobilized enzymes are compared. The results showed that the optimal saturation of ammonium sulfate was 80% for α-galactosidase from C. squamulosa. The enzyme activity retention rates of the two immobilized methods were both more than 50%, and the temperature stability, pH stability and storage time of immobilized enzyme were improved compared with that of free enzyme. After comparing the two immobilized enzymes, the temperature, acidity stability and operation stability of chitosan immobilized enzyme were better than that of sodium alginate immobilized enzyme. But the hydrolysis efficiency of chitosan immobilized enzyme on soymilk oligosaccharide was lower than the latter. The hydrolysis rate of oligosaccharide was more than 85% after the two immobilized enzymes were reused for 3 times. Compared with sodium alginate, chitosan was more suitable to be the immobilized carrier of α -galactosidase from C. squamulosa.

Leukocyte morphological parameters known as CPD (cell population data) is detected by hematology analyzer UniCel DxH800 with VCS technology. This study aimed to investigate the diagnostic efficacy of morphological changes in CPD parameters in distinguishing active tuberculosis from community-acquired pneumonia.

Tall-object lightning is one hot topic in the field of atmospheric electricity. In order to explore the application of Guangdong-Hong Kong-Macao Lightning Location System (GHMLLS) data on tall-object lightning, the performance of GHMLLS is evaluated based on the observation obtained at the Tall-Object Lightning Observatory in Guangzhou (TOLOG) during 2016 to 2017, and a preliminary comparative analysis on characteristics of lightning activities in the tall-object area in Guangzhou are made. Results show that the flash detection and the stroke detection of GHMLLS is about 93% (214/229) and 93% (449/481). The arithmetic mean (median) value of the location error is about 361 m(188 m), 252 m(167 m) and 294 m(173 m) for downward first negative strokes, downward subsequent negative strokes and upward negative strokes respectively. It is found that the cloud-to-ground (CG) lightning with higher grounding points are more likely to be misidentified as intro-cloud (IC) lightning by the GHMLLS. When the grounding point is (is not) lower than 200 m, the identification accuracy of the IC/CG classification is 99% (80%) and 93% (35%), respectively, for downward first negative strokes and the subsequent negative strokes. The accuracy of the IC/CG classification for upward negative strokes is found to be only 17%. According to statistical results of GHMLLS dataset from 2014 to 2018, negative IC records in tall-object area in Guangzhou are found to be more prominently gathered near buildings with height over 300 m than CG records, indicating that most negative IC records are actually tall-object strokes but just misjudged by GHMLLS. Mean shift algorithm is used to identify the lightning density centers of three relatively isolated tall buildings, namely the Canton Tower (600 m), the CITIC Plaza (390 m) and the GF Securities Headquarters (308 m). It's found that the number of strokes within the radius of 200 m in the lightning density center of the Canton Tower is about 5 times as much as that of the CITIC Plaza or the GF Securities Headquarters. It is speculated that most lightning occurred on the Canton Tower belonging to upward type, while those hitting the CITIC Plaza and the GF Securities Headquarters are mainly downward type.

Lightning can strike directly on buildings, lightning protection devices or the lateral surface of buildings, endangering buildings on the ground. Effective lightning protection measures can avoid lightning damage to buildings and prevent possible fire, explosion or other hazards. Striking distance is an important reference index in lightning protection design of buildings, which is widely used in various common lightning protection design methods, such as rolling ball method, collecting volume method, etc. With the development of social economy, there are more and more tall-object in modern cities. It becomes more challenging to accurately estimate the striking distance of buildings with different heights and to formulate more effective lightning protection schemes. Up to now, lots of researches on the attachment process of natural lightning are conducted, especially by means of optical observation, which mainly benefits from the intuition of optical data. Although a large number of observations have been made on the lightning attachment process, reports on the striking distance are still rare.Based on optical data of 21 lightning discharges on two steeple buildings, the Canton Tower (600 m, 12 cases) and the Guangsheng International Building (360 m, 9 cases) from 2012 to 2018, and data of return stroke peak current provided by Guangdong Power Grid Lightning Location System, influences of building height and return stroke peak current intensity on the striking distance are analyzed. Results show that the striking distance on higher buildings is longer, and the median lightning strike distance of the Canton Tower is about 2 times of that of the Guangsheng International Building. For buildings with a certain height, the striking distance tends to increase with the peak current increasing. Moreover, the higher the building is, the stronger the peak current of the corresponding return stroke is. The peak current of return stroke on the Canton Tower is obviously stronger than (about 1.7 times) that on the Guangsheng International Building. In the attachment process, the two-diensional average speed ratio of the downward leader and the upward leader is less than 4 at 0.1 ms before the return stroke. The number of cases with a ratio of 0 to 1 is the largest, accounting for about 65% of the total number of cases.

Comparing to the ground or low-object, tall-object is more likely to reach the threshold for the initiation of leader on its top due to the distortion and enhancement of electric field, therefore tall-object is not only easier to get struck by downward lightning, but also can initiate upward lightning. A field experiment, mainly focusing on the observation of lightning flashes terminating on tall structures, has been conducted since 2009 at the Tall-Object Lightning Observatory in Guangzhou (TOLOG), which is the important part of the Field Experiment Base on Lightning Sciences, China Meteorological Administration (CMA_FEBLS). Hundreds of tall-object lightning flashes have been captured during 2009-2018.For the lightning attachment process, tall-object will play the role of "magnifier":The TOLOG high-speed optical observation discovers the connection of the downward negative leader to the lateral surface of the upward connecting leader for the first time, and shows two basic types of the leader connection behaviors during the attachment process in negative cloud-to-ground lightning; the fine structure of negative stepped leader in natural lightning at close distance is revealed by using high-speed video records; the 2D/3D propagation characteristics of downward and upward leaders are analyzed; and the striking distances of lightning flashes to tall-object with different heights are also estimated.Tall-object plays an "amplifier" role on lightning electromagnetic field:Statistical analysis of the TOLOG data show that the magnetic field peak values induced by the first return stroke of lightning flashes to objects higher than 200 m is 2.4 times of that of lightning flashes to objects lower than 200 m; the higher the tall-object is, the larger the lightning location system inferred peak current of strokes are recorded in the vicinity of the tall-object; and the numberical simulation of the tall-object on electromagnetic field of lightning return stroke also show that the height of tall-object has significant enhancing effects.Tall-object is the "hot spot" of downward and upward lightning:Attraction effects of tall-object on downward lightning can protect other objects near tall-object from lightning strikes; the upward negative lightning from the tall-object can be triggered by the return stroke, the continuing current or the discharging process in cloud of positive cloud-to-ground lightning; and in upward lightning, abrupt extension is found at the positive end of the recoil leader which propagates bidirectionally.Using data of the TOLOG, the detection efficiency, the location error and the systematic bias of lightning location systems in Guangdong are evaluated, showing that the observation area of the TOLOG can be used as a "calibration field" for ground-based or space-based lightning monitoring system.

One of the most important advances in lightning physics research in recent decades is the introduction of the the bidirectional developmengt of leaders and its observation and verification, but this theory is not paid much attention until more and more observation results of natural lightning, long gap spark discharge in laboratory and artificially triggered lightning have proved the correctness of the concept.The theory is used to establish the model of leader to interpretate the physical mechanism of lightning initiation and development. High-speed video camera observation not only provides direct evidence for the development of bidirectional leader, but also gives details of positive and negative ends. Previous observations show that the negative leader developed in a step-wise manner by relying on the space stem/leader and the corona streamer at the front of the new leader's tip. Positive leaders propagate in a continuous or step-wise manner, but to date, characteristics and mechanisms of the development of positive leaders are still unclear. In recent years, the abrupt elongations of the positive leader (or the positive end of bidirectional leader) are found in the high-speed video observation of the leader. This phenomenon might be closely related to the propagation mechanism of the positive leader and deserves further observation and analysis.Based on synchronization data of high-speed video camera and electric field change of an upward flash at the Canton Tower, the abrupt elongations phenomenon of the positive end before and after the return stroke is analyzed in detail.Results show that the positive end of the second dart leader intermittently extends into the air. There are three abrupt elongations of the second dart leader of the positive end, and the second abrupt elongation is caused by the connection between the positive end and the floating channel in which the tip of the positive end appears. After the second subsequent return stroke, there are two abrupt elongations of the channel tip. The two-dimensional average speed of the three abrupt elongations of the positive end is approximately 2.3×106 m·s-1, and the average length of the three abrupt elongations is approximately 115 m. After the return stroke, the two-dimensional average speed of the two abrupt elongations of the channel tip is approximately 4.3×106 m·s-1, and the average length of the two abrupt elongations is approximately 212 m.

Abstract This paper presents the design, fabrication, and characterization of a middle-infrared (MIR) linear variable optical filter (LVOF) and thermopile detectors that will be used in a miniaturized mixed gas detector for CH4/CO2/CO measurement. The LVOF was designed as a tapered-cavity Fabry-Pérot optical filter, which can transform the MIR continuous spectrum into multiple narrow band-pass spectra with peak wavelength in linear variation. Multi-layer dielectric structures were used to fabricate the Bragg reflectors on the both sides of tapered cavity as well as the antireflective film combined with the function of out-of-band rejection. The uncooled thermopile detectors were designed and fabricated as a multiple-thermocouple suspension structure using micro-electro-mechanical system technology. Experimentally, the LVOF exhibits a mean full-width-at-half-maximum of 400 nm and mean peak transmittance of 70% at the wavelength range of 2.3~5 μm. The thermopile detectors exhibit a responsivity of 146 μV/°C at the condition of room temperature. It is demonstrated that the detectors can achieve the quantification and identification of CH4/CO2/CO mixed gas.

Poly (butylene furandicarboxylate) based poly (ether ester), with poly (ethylene glycol) (PEG) molecular weight from 600 to 20 K g mol−1 and mass fraction of hard segments fixed at 50%, are synthesized through transesterification and melt polycondensation. When Mn (PEG) is less than 1500 g mol−1, the copolymers tend to be homogeneous. The tendency of microphase separation is facilitated by the increasing Mn (PEG). The mechanical properties and water swelling are influenced by Mn (PEG), equilibrium water-uptake and PEG crystals. Elastic modulus of samples with no PEG crystals vary from 34 to 64 MPa, with elongation at break exceeding 1000%. The hydrolytic degradation is strongly affected by Mn (PEG), degradation medium and alkalinity. The degradation of copolymers with short PEG (

BackgroundRegnase-1 (MCPIP) has been identified as an anti-inflammatory agent, but little is known about its influence on liver ischemia/reperfusion (I/R) injury. Macrophages can evolve biphasic responses and differentiate into remarkable polarizations, contributing greatly to the uncontrolled inflammatory cascades during liver I/R injury. Therefore, the aim of this study was to explore whether regnase-1 participated in liver I/R via manipulating macrophage polarization.Materials and methodsC57BL/6 mice were randomly divided into five groups: Sham, I/R, Clodronate, Clo + BMDM, and Clo + LV MCPIP BMDM. A liver I/R model was established, and histopathological and immunostaining examinations were performed for the liver specimens; double immunofluorescence staining was used to localize MCPIP in the liver. Primary hepatocytes were isolated to simulate a hypoxia and reoxygenation (H/R) model in vitro. Bone marrow-derived macrophages (BMDM) were extracted and subjected to lentiviral transduction to knockdown MCPIP expression. BMDM with or without MCPIP deletion were exposed to H/R supernatants, and the polarized states were measured by flow cytometry. RT-PCR analysis and Western blot were also conducted.ResultsCompared to those in the Sham group, liver functions and Suzuki’s scores were deteriorated in the I/R group, which were reversed in the Clodronate group. The increased expression of regnase-1 in the I/R group diminished with pretreatment of clodronate liposomes. Subsequent double immunofluorescence staining established the localization of regnase-1 in macrophages in the liver. The insulted lesions in the Clodronate group became progressively aggravated with adoptive transfer of BMDM in the Clo + BMDM group, and they were further exacerbated with the transfusion of BMDM with MCPIP knockdown in the Clo + LV MCPIP BMDM group. Gene expressions of M1 and M2 markers were detected by RT-PCR, suggesting that MCPIP knockdown tended to favor the M1 transformation. Subsequently, ex vivo flow cytometrical detection showed that, upon stimulation by H/R supernatants, LV-MCPIP BMDM posed a higher ratio of M1/M2 than BMDM. Finally, we found that MCPIP participated in macrophage M1/M2 polarization through the NF-κB, C/EBPβ, and PPARγ signaling pathways during liver I/R.ConclusionOur study confirms that regnase-1 plays a critical role in liver I/R via regulation of macrophage polarization and, thus, might offer a potential therapeutic target.

Tests on twelve circular concrete-filled steel tube stub columns with mixed red mud and three circular concrete-filled steel tube stub columns to investigate the influence of the mixed proportion of red mud on the mechanical behavior of axial compressive circular concrete-filled steel tube stub columns are reported. It is found that with the increase of red mud content, the ultimate load increases first and then decreases; on the contrary, the ultimate displacement decreases first and then increases; the specimen stress reaches the proportion limitation as the steel tube longitudinal strain is around 160 με and reaches the yield limitation as the steel tubes’ longitudinal strain is around 4400∼5000 με. The axial compressive bearing capacity empirical formulation of concrete-filled steel tubes stub columns mixed with red mud is proposed. The theoretical calculation results agree well with those experimental data.

At present, most of the network attack effect evaluation is based on mathematical theory. The calculation process is influenced by artificial judgment, and the research on the dependence and influence between indicators is not sufficient, so the index weight setting is too subjective. This paper proposes a network attack effect evaluation model based on directed weighted complex network, and constructs an index architecture based on attribute-attack type-atomic function-evaluation index four-layers subnetwork. The index importance calculation method is given by combining the complex network theory with the traditional fuzzy analytic hierarchy process. Finally, taking the password cracking attack as an example, it is proved that this method is helpful to explore the impact mechanism of indicators on attributes, fully considers the relationship between indicators, simplifies the index system and improves the evaluation efficiency.

Electric hot incremental sheet forming, which is used to form hard-to-form sheet metal, is viewed as the one of rapid prototyping manufacturing technologies. However, the non-uniform stress distribution of forming regions would cause an initial contact loss phenomenon between the tool and the sheet, and an electric arc burn of the part surface is obtained due to the contact loss. In this work, a control method of axial pressure response was proposed to judge the stability of the initial contact between forming the tool and the sheet. A power supply on-off device was designed for electric hot incremental forming, and the calculation model of the initial axial force was established during deformation. Meanwhile, two response pressure values were proposed to control the power supply starting and the current intervention and to ensure the stability of the power supply during the forming process. In addition to this, the axial force and the surface of part were analyzed further in electric hot incremental sheet forming.

In social network,original publisher and important nodes in the diffusion process can be traced by analyzing the spreading network of a hot topic.The participated users and spreading network structure of a hot topic build an information tracing model,which mines the source and important diffusion nodes.Firstly,it analyzed the development trend of a hot topic and extracts the users involved.Secondly,it established a user network according to the following relationship of the users involved.Thirdly,the contribution rate of users on the development of the hot topic was initialized,and the PageRank algorithm was used to construct the information tracing model.Finally,the Top k users were selected as the information publisher and important users of the hot topic according to the contribution rate.Experimental results showed that our model can effectively discover the hot topic of the publisher and important users.