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High-end CNC machine tools' primary transmission mechanism is a high-speed electric spindle. Thermal displacement of the spindle occurs as a result of heat created inside the spindle during transmission, which has an impact on the machining precision of high-end CNC machine tools. Establishing a high-precision motorized spindle simulation model is crucial because it serves as a foundation for optimizing and testing the motorized spindle's construction and material, adjusting for thermal errors, and estimating its life. The thermal-solid coupling model of the motorized spindle is created by Ansys based on the experimental data of temperature and thermal displacement of the A02 motorized spindle and in accordance with the boundary conditions. The accuracy of front and rear bearings is 93.42% and 90.52%, respectively, when compared to experimental data, and the accuracy of axial thermal displacement is 95.16%. Finally, the motorized spindle is optimized to extend its service life after the thermal displacement, stress, and strain of the bearing are model.

The coprevalence of chronic heart failure (CHF) and depression is 10%-79%, the pathogenesis of these two diseases is related to the activation of immune inflammatory system, insulin resistance and intestinal flora imbalance, and relevant regulation is bidirectional and complex. There is a lack of efficient drugs for both CHF and depression recommended by available diagnosis and treatment guidelines and present clinical practice. But it has recently been reported that some drugs (sacubitril/valsartan, new antidepressants, shensongyangxin and qiliqiangxin capsules, regulators of the intestinal flora) may be partially effective for CHF with depression.We reviewed the mechanism of coexistence and pharmaceutical treatment of CHF and depression, providing new ideas and evidence for clinical diagnosis and treatment of CHF and depression.

Due to constraints in launch platforms and cost, the maneuverability of gliding-guided projectiles is limited, necessitating a rational design of their trajectory schemes. To reduce the sensitivity of trajectory schemes to uncertainties while ensuring compatibility between flight schemes and guidance control systems and fully exploiting the control capability of the projectile, a closed-loop robust trajectory planning method is proposed. Models of major uncertain factors and state deviation at the control start point are established. Based on the NIPCE method, the stochastic dynamic model is transformed into a high-dimensional deterministic model with PCE coefficients as state variables, and the uncertainty propagation law is obtained. A PID algorithm is employed to design a tracking guidance law based on position error feedback, and open-loop and closed-loop robust trajectory planning models are established accordingly. The optimal control problem is solved by transforming it into a nonlinear programming problem using the direct shooting method. Our simulation results indicate that the NIPCE method can significantly improve the computational efficiency of uncertainty propagation while ensuring accuracy; compared with parallel MCS, the computation time is reduced by 96.8%. Open-loop robust planning can effectively mitigate the sensitivity of gliding trajectories to uncertainties (the standard deviations of terminal altitude and lateral deviations are reduced by 23.6% and 35.3%, respectively, compared to deterministic planning) but cannot completely eliminate terminal dispersion. Closed-loop robust planning effectively improves control effort consumption on the basis of open-loop planning. [ABSTRACT FROM AUTHOR]

In order to study the missile separation safety under the condition of full envelope launch, a new type of double parallelogram ejection configuration is adopted in this paper. The combined flexible multi-body launching dynamics simulation method based on ABAQUS and ADAMS is used to obtain the missile separation velocity, angular velocity, overload, dynamic load of key components and lateral deformation of missile carrier system. The simulation results show that the lateral overload has a significant impact on the separation safety of missile carrier and the structural compatibility of weapon and carrier. On this basis, a method to optimize the lateral deformation of missile carrier system is proposed.

Cadmium (Cd) is a naturally occurring toxic heavy metal that adversely affects plant germination, growth, and development. While the effects of Cd have been described on many crop species including rice, maize, wheat and barley, few studies are available on cadmium's effect on Tartary buckwheat which is a traditional grain in China. We examined nine genotypes and found that 30 µM of Cd reduced the root length in seedlings by between 4 and 44% and decreased the total biomass by 7 to 31%, compared with Cd-free controls. We identified a significant genotypic variation in sensitivity to Cd stress. Cd treatment decreased the total root length and the emergence and growth of lateral roots, and these changes were significantly greater in the Cd-sensitive genotypes than in tolerant genotypes. Cd resulted in greater wilting and discoloration in sensitive genotypes than in tolerant genotypes and caused more damage to the structure of root and leaf cells. Cd accumulated in the roots and shoots, but the concentrations in the sensitive genotypes were significantly greater than in the more tolerant genotypes. Cd treatment affected nutrient uptake, and the changes in the sensitive genotypes were greater than those in the tolerant genotypes, which could maintain their concentrations closer to the control levels. The induction of SOD, POD, and CAT activities in the roots and shoots was significantly greater in the tolerant genotypes than in the sensitive genotypes. We demonstrated that Cd stress reduced root and shoot growth, decreased plant biomass, disrupted nutrient uptake, altered cell structure, and managed Cd-induced oxidative stress differently in the sensitive and tolerant genotypes of Tartary buckwheat. [ABSTRACT FROM AUTHOR]

We studied newly found high Nb-Ta alkaline rhyolites in the northern volcanic belt of the Great Xing'an Range, China. The LA-ICP-MS U-Pb weighted mean age is 114.07 [+ or -] 0.55 Ma, indicating that the rocks formed during the late Early Cretaceous and were the product of the late eruption of a Mesozoic volcano. The major element contents are characterized by high Si, rich K, low Fe, and poor Ca and Mg. In the total alkaline--silicon diagram, the sample points are in the alkaline rhyolite region. Meanwhile, rare earth elements show obvious Ce/Ce* positive anomalies and Eu/Eu* negative anomalies. In addition, trace elements are characterized by high Nb, Ta, and Yb, and low Sr. The two-stage Nd isotopic model age [T.sub.2]DM of the depleted mantle is between 799-813 Ma, indicating that the diagenetic material originated from the depleted mantle or partial melting of newly formed young crustal materials. The source rocks melted at a relative shallow depth ( Key words: Xingan block, high Nb-Ta, alkaline rhyolite, zircon U-Pb chronology, geochemistry, petrogenesis. Nous avons etudie des rhyolites alcalines riches en Nb-Ta decouvertes recemment dans la ceinture volcanique septentrionale de la chaine du Grand Xing'an (Chine). L'age U-Pb pondere moyen obtenu par LA-ICP-MS est de 114,07 [+ or -] 0,55 Ma, ce qui indique que les roches se sont formees vers la fin du Cretace precoce et sont le produit de l'eruption tardive d'un volcan mesozoique. La signature des elements majeurs est riche en Si et K et pauvre en Fe, Ca et Mg. Dans le diagramme alcalis totaux-silice, les echantillons tombent dans la region des rhyolites alcalines. Les terres rares presentent pour leur part des anomalies positives du rapport Ce/Ce* et negatives du rapport Eu/Eu*; la signature des elements traces est en outre riche en Nb, Ta et Yb et pauvre en Sr. L'age [T.sub.2]DM obtenu des isotopes de Nb pour un modele a deux etapes du manteau appauvri est de 799-813 Ma, indiquant que le materiau source provient du manteau appauvri ou de la fusion partielle de jeunes materiaux crustaux nouvellement formes. La fusion des roches sources s'est produite a relativement faible profondeur ( Mots-cles : bloc de Xing'an, Nb-Ta eleves, rhyolite alcaline, geochronologie U-Pb sur zircon, geochimie, petrogenese., Introduction The northern volcanic belt of the Great Xing'an Range is the superimposed portion of the ancient Asian oceanic tectonic domain, the Pacific domain, and the Mongolia--Okhotsk oceanic domain (Wu [...]

Based on the air quality monitoring data and meteorological data, the pollution characteristics of PM2.5 in southern Beijing and relationships between PM2.5 levels and meteorological features were analyzed. The results showed that during the investigation period, daily air quality was characterized as "excellent" and "favorable" (<75 µg m−3) on 77% of days in southern Beijing, and there were only two days with serious air pollution (>250 µg m−3). The PM2.5 concentration displayed obvious monthly variations with the highest concentration in November and the lowest concentration in August. When PM2.5 pollution episodes occurred (>75 µg m−3) in this area, the wind direction was often south and southeast with low wind speed (<3 m∙s−1), followed by southwest wind; in addition, the air temperature was low (<10 °C) and the relative humidity was high (>75%). The air quality of the study area was affected by the pollution transmission form the surrounding areas, especially the southeastern and the southern transmission paths. The PM2.5 concentration was positively correlated with SO2, NO2 and CO, and negatively correlated with O3. Therefore, to further improve the air quality in the study area, it is necessary to coordinate the control of PM2.5 and O3. [ABSTRACT FROM AUTHOR]

Miscanthus spp. show excellent application prospects due to its bioenergy potential and multiple ecological services. Annual N export with biomass harvest from Miscanthus, even without fertilizer supplement, do not reduce soil N levels. The question arises regarding how Miscanthus can maintain stable soil N levels. Metagenomic strategies were used to reveal soil N‐cycling‐related microbiome and their functional contributions to processes of soil N‐cycling based on the comparison among the bare land, cropland, 10‐year Miscanthus × giganteus, and 15‐year Miscanthus sacchariflorus fields. The results showed that, after long‐term cropland‐to‐Miscanthus conversion (LCMC), 16 of 21 bacterial phyla and all the archaeal phyla exhibited significant changes. Soil microbial denitrification and nitrification functions were significantly weakened, and N fixation (NF) was significantly enhanced. The biosynthesis of amino acids, especially alanine, aspartate, and glutamate metabolism, in soil N‐cycling‐related microbiome was dramatically promoted. The genus Anaeromyxobacter contributed largely to the NF process after LCMC. Variations in the soil available potassium, available N, organic C, and total N contents drove a functional shift of soil microbiome from cropland to Miscanthus pattern. We conclude that Miscanthus can recruit Anaeromyxobacter communities to enhance NF benefiting its biomass sustainability and soil N balance. [ABSTRACT FROM AUTHOR]