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Panax notoginseng belongs to the long stemmed crop, and the harvesting of its stems and leaves is one of the important processes. Aming at the problems of high labor intensity and lack of mature harvesting equipment, based on the agronomic requirements of Panax notoginseng cultivation and the mechanical parameters of Panax notoginseng stems, a harvesting device for Panax notoginseng stems and leaves under the forest was designed, which mainly consisted of a control box, a frame, and a leaf cutting device. The overall size, cutting stroke, forward speed and cutting pair width of the device were determined, and the device structure was compacted, which met the requirement of harvesting. The design of key structural parameters for reciprocating cutters mainly included moving blade, fixed blade, crank connecting rod mechanism, blade protector, etc. The reciprocating cutter could meet the technical requirements while didn't damage seedlings and miss cutting Panax notoginseng stems and leaves. A kinematic analysis was conducted on the cutter, and it was determined that the cutting speed was 0.4~0.8 m·s-1, which ensured the cutting effect while also ensuring the stability and safety of the entire machine. A rigid flexible coupling simulation model of Panax notoginseng stem and cutting blade was constructed, and cutting blade simulation analysis was carried out with the maximum cutting force as evaluation index. Based on three factors and three levels test results, it was found that the factors affecting cutting from large to small were cutting angle, cutting speed and tool configuration. The reduction effect of blade shape on Panax notoginseng stem cutting force was determined, with triangular blade>trapezoidal blade>rectangular blade, The optimal parameter combination for the stem cutting blade of Panax notoginseng was cutting angle of 90.5°, triangular blade shape, and cutting speed of 0.52 m·s-1. At this condition, the maximum cutting force was 7.46 N, which met cutting requirements. [ABSTRACT FROM AUTHOR]

Objectives: This study evaluated the feasibility and safety of zone 1 thoracic endovascular aortic repair (TEVAR) with fenestrated surgeon-modified stent-graft (SMSG) for aortic arch pathologies. Methods: Between March 2016 and November 2020, 34 consecutive patients underwent zone 1 TEVAR with fenestrated SMSG for aortic arch pathologies. Outcomes included technical success, perioperative, and follow-up morbidity and mortality. Results: During the study period, 34 patients were treated with zone 1 TEVAR with fenestrated SMSG. Twenty-four (70.6%) patients presented with type B aortic dissections, 9 (26.5%) patients presented with aneurysms (7 located on the lesser curvature side of aortic arch), 1 (2.9%) patient presented with type Ia endoleak after previous TEVAR owing to traumatic aortic dissection. The proximal landing zone for all patients were in zone 1, and all supra-aortic trunks were reconstructed, except for one left subclavian artery. Technical success was achieved in all cases. The 30-day estimated survival (±SE) was 90.9% ± 5.0% [95% confidence interval (CI): 77.0%–97.0%]. The 30-day estimated freedom from reintervention (±SE) was 87.9% ± 5.7% (95% CI: 73.4%–95.3%). At a median follow-up of 48 months (range, 12–68 months), 2 patients died, including 1 aortic-related death and 1 non-aortic-related death. One patient had reintervention 13 months after the operation owing to type Ia endoleak. All supra-aortic trunks were patent. The estimated survival (±SE) during follow-up was 85.1% ± 6.2% (95% CI: 69.9%–93.6%). One (2.7%) patient had stroke. The estimated freedom from reintervention (±SE) during follow-up was 84.2% ± 6.5% (95% CI: 69.9%–93.5%). Conclusions: Zone 1 TEVAR with fenestrated SMSG is an alternate option for treatment of aortic arch pathologies in experienced centers. [ABSTRACT FROM AUTHOR]

Soil organic matter (SOM) is a key indicator of soil fertility. For accurate measurement of SOM, a novel method based on an artificial olfactory system (AOS) was proposed. The response curves of soil volatile organic compounds (VOCs) were measured using a metal-oxide semiconductor sensor array, and four features (including maximum value, mean differential coefficient, response area, and the transient value at the 20th second) were obtained from the curves and used to build olfactory feature space. Then, prediction models were established using the pattern recognition algorithm. To further enhance the accuracy of AOS measurement, we used Monte Carlo cross-validation (MCCV) to identify and eliminate the abnormal samples of the soil olfactory feature space. Then, the dimension reduction method of the genetic algorithm (GA)back-propagation (BP) was used to find the appropriate feature vectors, and two types of hybrid models were presented. One was the support vector machine (SVM) and group method of data handling (GMDH) combined model—SVM-GMDH. The other was a combination of partial least squares regression (PLSR) and back-propagation neural network (BPNN)—PLSR-BPNN. The forecasting performances of three single models (BPNN, PLSR, support vector regression: SVR) and two combined models (PLSR-BPNN, SVM-GMDH) were comparatively evaluated. The evaluation indices included coefficient of determination (R2), root mean square error (RMSE), ratio of performance to deviation and relative prediction error (RPE). It was found that the predictive capabilities of all five tested models were improved after elimination of abnormal samples and feature reduction. Moreover, PLSR-BPNN performed the best in predicting SOM concentrations, with R2 = 0.952, RMSE = 1.771, PRD = 4.291, and slight variation of RPE within 0–0.185, and thus can offer a reference for predicting SOM via AOS. [ABSTRACT FROM AUTHOR]

Background: To assess the feasibility and first-in-human experience of a novel endovascular robotic system for treatment of lower extremity peripheral arterial disease (PAD)., Methods: Between November 2021 and January 2022, consecutive patients with obstructive lower extremity PAD and claudication (Rutherford 2-5) with >50% stenosis demonstrated on angiography were enrolled in this study. Lower extremity peripheral arterial intervention was performed using the endovascular robotic system, which consisted of a bedside unit and an interventional console. The primary endpoints were technical success, defined as the successful manipulation of the lower extremity peripheral arterial devices using the robotic system, and safety. The secondary endpoints were clinical success, defined as 50% residual stenosis at the completion of the robot-assisted procedure without major adverse cardiac events and radiation exposure., Results: In total, 5 patients with PAD were enrolled in this study (69.2±6.0 years; 80% men). The novel endovascular robotic system successfully completed the entire procedure of endovascular treatment of lower extremity PAD. Conversion to manual operation, including advancement, retracement, rotation of the guidewires, catheters, sheaths, deployment, and release of the balloons and stent grafts, was not necessary. We achieved the criteria for clinical procedural and technical success in all patients. No deaths, myocardial infarctions, or ruptures occurred in the period up to 30 days after the procedure, and no device-related complications were observed. The robotic system operator had 97.6% less radiation exposure than that at the procedure table, with a mean of 1.40±0.49 μGy., Conclusions: This study demonstrated the safety and feasibility of the robotic system. The procedure reached technical and clinical performance metrics and resulted in significantly lower radiation exposure to the operators at the console compared with that at the procedure table., Clinical Impact: There were some reports about several robotic systems used in the peripheral arterial disease, but no robotic system was able to perform entire procedure of endovascular treatment of lower extremity peripheral arterial disease (PAD).To solve this problem, we designed a remote-control novel endovascular robotic system. It was the first robotic system that can perform entire procedure of endovascular treatment of PAD worldwide. A novelty retrieval report about this is provided in the supplementary materials.The robotic system is compatible with all commercial endovascular surgical devices currently available in the market, including guidewires, catheters and stent delivery systems. It can perform all types of motion, such as forward, backward, and rotation to meet the requirements of all types of endovascular procedures. During the operation, the robotic system can perform these operations in a fine-tuned manner, so it is easy to cross the lesions, which is the key factor influencing the success rate of the operation. In addition, the robotic system can effectively reduce the exposure time to radiation, thereby reducing the risk of occupational injury.