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[Objective] The study aims to reveal the pollination Ottelia acuminata and O. acuminata var. crispa, elucidate the factors affecting successful pollination, and provide theoretical and technical guidance for hybrid breeding between the two species. [Methods] Using O. acuminata and O. acuminata var. crispa as subjects, by observing their flowering dynamics, insect visitation behaviors, and measuring pollen viability, stigma receptivity, and hybrid compatibility index, the study investigated their pollination characteristics and hybrid compatibility. [Results] The flowering dynamics of O. acuminata and O. acuminata var. crispa were fundamentally similar, with each flower lasting 7-11 h. The main pollinating insects include Episyrphus balteatus and Apis cerana. The vitality of the pollen and the receptivity of the stigma both showed an initial increase followed by a decrease. The peak pollen viabilities for O. acuminata and O. acuminata var. crispa were 88.27% and 88.34%, respectively, and the stigmas were all the highest at anthesis Ⅱ. The fruit set rates for direct and reciprocal crosses were 85.71% and 91.33%, respectively, with hybrid compatibility indices both greater than 53. The average number of seeds per fruit for self-pollination were 54 and 69, respectively, and for direct and reciprocal crosses, 73 and 71, respectively. The seed germination rates for self-pollination were 71.7% and 27.3%, respectively, and for direct and reciprocal crosses, 22.6% and 19.7%, respectively. [Conclusion] The flowering dynamics of O. acuminata and O. acuminata var. crispa are fundamentally similar, with each having a short flowering period. There are fewer types of pollinating insects, which affects sexual reproduction, yet there is no significant evidence of hybrid incompatibility.

[Objective] Plant resources of the Micang Mountain Nature Reserve in Shaanxi Province were identified through field survey. This investigation provided a theoretical basis for the study of the flora of Shaanxi Province, and was of great significance for the protection and utilization of plant resources in Shaanxi Province. [Methods] One newly recorded genus and four newly recorded plants in Shaanxi Province were determined by consulting the literature and comparing the specimens in collections. [Results] One newly recorded genus of the vascular plants, Gonocarpus Thunberg, and its newly recorded species Gonocarpus micranthus Thunberg in Shaanxi Province were determined. In addition, three newly recorded plants were found, including Viburnum atrocyaneum C. B. Clarke (Viburnaceae), Carpesium minus Hemsley (Asteraceae), and Euonymus oxyphyllus Miquel (Celastraceae). [Conclusion] This study improves the records of vascular plants in Shaanxi province. The voucher specimens are stored in the herbarium of Northwest A&F University (WUK).

Based on the characteristics of the No.3 coal seam and No.15 coal seam in Zhengzhuang Field and the need for low-cost and high-efficiency development of coalbed methane, a technical method for enhancing coalbed methane mining in non-cemented L-type staged fracturing horizontal wells in coal seams is proposed. The numerical simulation results show that hydraulic jet fracturing can produce 1.5-2.0 MPa annular sealing effect and 3.5-4.5 MPa hole pressurization effect, which can meet the purpose of annular air anti-channeling and fixed-point fracturing in the non-cemented horizontal wells. In view of the construction technology problems in drilling and completion, fracturing and drainage of non-cemented coalbed methane horizontal wells, four core key technologies have been explored, including “high-quality, fast and safe” drilling and completion technology, coiled tubing with bottom seal fast dragging jet-fracturing combined staged fracturing technology, “large displacement, large-scale, medium-sand ratio” active water fracturing stimulation technology, L-shaped horizontal well fine drainage control technology. Practice has proved that the non-cementing staged fracturing horizontal well development technology for coalbed methane has achieved large-scale application in Zhengzhuang Field, and achieved a double breakthrough in coalbed methane development technology and high gas production.

Considering that some tasks will require the consistency of the position and attitude of the end-effector, multi-space-robot cooperative capture also needs to consider the synchronization of the two capture arms. Taking the dual-space robots as example, the trajectory planning problem before cooperative capture is focused. First, a drive-transform method based on trapezoidal velocity interpolation is proposed, which combines the advantages of these two methods to obtain the SE(3) motion trajectory, in which the attitude and position are planned synchronously. Then, the trajectory optimization model of cooperative capture is established, which takes the optimal time and the minimum attitude disturbance of the base as the optimization goals, and simultaneously satisfies that the two capture arms reach the capture point synchronously. In order to solve this multi-objective optimization problem, a dual-population multi-objective fruit fly algorithm based on non-dominated sorting was proposed. Finally, the simulation example of dual-space robots shows that the proposed algorithm is effective, and the analysis of the optimal solution set demonstrates that the optimized cooperative capture trajectory is smooth and synchronous.

Abstract Background To determine the risk-assessment role of the immune-inflammatory biomarkers on myocardial damage in COVID-19 patients with diabetes mellitus (DM). Methods This retrospective study was conducted on 822 COVID-19 inpatients from 1 January to 10 March 2020 at Renmin Hospital of Wuhan University. The demographic data, clinical data, and immune-inflammatory parameters of participants were collected. The predictors of cardiac injury were assessed by Logistics regression analysis. Results A total of 246 COVID-19 inpatients were diagnosed with DM (29.9%). The incidence of cardiac injury was higher in patients with DM than in non-DM cases (28.9% vs 9.0%, p 25.68mpg/ml (adjusted OR, 4.345; 95% CI 2.192–10.374; p

This paper takes the multi-branch horizontal grouting well reinforced with limestone on the corresponding floor L8 in the 15011 coal seam working face of Zhaogu No.1 Mine as the research object. Pilot hole in treated limestone layer is designed and drilled to obtain the buried depth, gamma value, ROD of geometrical parameter and structural information, and to accurately design and control landing point of limestone layer of the main hole of multi-branch horizontal grouting well; optimizing the conventional multi-branch horizontal grouting well drilling tool assembly, preferring to centralizer with under-size symmetrical and ball centralizer with ball on the screw and under-sized protrusions to form a dual stabilized drilling tool assembly to reduce the drift of deviation and azimuth during directional and compound drilling and reduce the frequency of adjustment for branch hole trajectory and length of directional segment. Based on the above technical measures, accurate control of the multi-branch horizontal grouting well trajectory in the L8 limestone layer has been achieved for stable drilling.

Raise boring method is one of the key technologies for coal mine shaft construction. The typical engineering of raise boring method is two types: large diameter shafts and small diameter gas pipeline shafts. Ensuring the stability of these two types of shaft structures is a key issue that determines the quality of raise boring engineering. In order to solve this problem, a method of evaluating the stability of shaft structure constructed by raise boring method is proposed in this paper. First, for large-diameter shafts, it is clear that the stability of surrounding rock is the key factor. Based on the strength reduction method, the stability coefficient of surrounding rock k0=2.5 is proposed. Secondly, for the small diameter gas pipe shaft, it is clear that the stability of the gas pipe under the pressure of the filling material is the key factor. The functional equations of allowable compressive stress of the pipe material, the initial deviation of the gas pipes and the ultimate pressure are established, and a method with results biased towards safety is proposed for the design and verification of gas pipes.

As a new industry, cold chain logistics has attracted much attention. Under the strong support of national policies, the development of cold chain logistics has entered the fast lane. This study takes the energy consumption of cold chain logistics as the research object, uses the the energy consumption benchmark evaluation model of regression analysis to present the current situation of energy consumption of cold chain logistics from different dimensions, puts forward the contradictions and problems existing in the current development based on the SWOT (strengths, weaknesses, opportunities and threats) analysis method. Finally, the development trend of cold chain logistics energy consumption is predicted and relevant suggestions are put forward. The purpose of this paper is to find out the rule of effect of each factor on energy consumption in cold chain logistics, and to provide the direction for energy-saving measures in production.

BACKGROUND: The PI3K/AKT pathway transduces the majority of the metabolic actions of insulin. In addition to cytosolic targets, insulin-stimulated phospho-AKT also translocates to mitochondria in the myocardium. Mouse models of diabetes exhibit impaired mitochondrial AKT signaling but the implications of this on cardiac structure and function is unknown. We hypothesized that loss of mitochondrial AKT signaling is a critical step in cardiomyopathy and reduces cardiac oxidative phosphorylation. METHODS: To focus our investigation on the pathophysiological consequences of this mitochondrial signaling pathway, we generated transgenic mouse models of cardiac-specific, mitochondria-targeting, dominant negative AKT1 (CAMDAKT) and constitutively active AKT1 expression (CAMCAKT). Myocardial structure and function were examined using echocardiography, histology, and biochemical assays. We further investigated the underlying effects of mitochondrial AKT1 on mitochondrial structure and function, its interaction with ATP synthase, and explored in vivo metabolism beyond the heart. RESULTS: Upon induction of dominant negative mitochondrial AKT1, CAMDAKT mice developed cardiac fibrosis accompanied by left ventricular hypertrophy and dysfunction. Cardiac mitochondrial oxidative phosphorylation efficiency and ATP content were reduced, mitochondrial cristae structure was lost, and ATP synthase structure was compromised. Conversely, CAMCAKT mice were protected against development of diabetic cardiomyopathy when challenged with a high calorie diet. Activation of mitochondrial AKT1 protected cardiac function and increased fatty acid uptake in myocardium. In addition, total energy expenditure was increased in CAMCAKT mice, accompanied by reduced adiposity and reduced development of fatty liver. CONCLUSION: CAMDAKT mice modeled the effects of impaired mitochondrial signaling which occurs in the diabetic myocardium. Disruption of this pathway is a key step in the development of cardiomyopathy. Activation of mitochondrial AKT1 in CAMCAKT had a protective role against diabetic cardiomyopathy as well as improved metabolism beyond the heart.

Based on the theory of high pressure supercooling and pressure relief quick freezing, the ultra-high pressure instantaneous freezing device is developed. This device can break through the limitations of existing ultra-high pressure device design. Through the new hydraulic transmission design, It can complete fast pressurization, fast pressure relief and achieve continuous work. The matching of whole systems under certain load conditions, hydraulic transmission system, refrigeration system, pressure vessel and pressure relief system has been completed. The device can realize the whole process of ultra-high pressure quick freezing from food feeding, pressure cooling, pressure relief instant freezing and semi-automatic food discharging. Compared with the conventional same-capacity quick-freezing device, the energy consumption of the instantaneous freezing device under the design condition is only 24.52% of that of the traditional quick-freezing device, which greatly saves energy consumption. From the perspective of application, the design concept of ultra-high pressure quick-freezing device is perfected and the practical process of ultra-high pressure quick-freezing is advanced.