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The swing torque and rotational torque after the spherical bearing is installed directly affect the performance of the spherical bearing. At this stage, the friction torque detection equipment of the spherical bearing is mainly used to detect uninstalled bearings. A set of rotation and swing after the bearing is installed is designed. Torque detection system. The detection principles of rotational torque and swing torque required for flexibility detection were analyzed, the functional design requirements and main technical indicators of the detection system were clarified, and the overall design plan of the detection system was established; the host structure of the detection system was designed, including rotational torque detection system, swing torque detection system, clamping system and calibration system; completed the scheme design of the detection control system, selected the torque sensor and servo motor, designed the main electrical control circuit of the detector; conducted error analysis of the detector. [ABSTRACT FROM AUTHOR]

In order to obtain better-polished surface quality of hard anodic oxide film, two deep learning models of the BP neural network and GA-BP neural network were used to establish a roughness prediction model for aluminum alloy hard anodic oxide film polishing. The experimental data was divided into two groups, one group of data was used for model training, and the other group of data was used for model testing. The results showed that the mean square error between the polishing roughness predicted by the BP neural network model and the experimental results was 1.33E-2, the maximum relative error was 18.84 %, the minimum relative error was 0.77 %, and the average relative error was 10.46 %. The error is relatively large, and the degree of variation of the error is relatively large; the mean square error of the polishing roughness predicted by the GA-BP neural network model and the test results is 0.58E-2, the maximum relative error is 14.28 %, the minimum relative error is 0.51%, the average relative error is 6.61 %, the error is smaller, and the degree of error change is smaller; the prediction accuracy of the GA-BP model is the highest, and the generalization ability strongest. [ABSTRACT FROM AUTHOR]

Background: Drought is one of the main environmental factors limiting tree growth and productivity of plantation forests worldwide. Populus hopeiensis Hu et Chow is one of the most important commercial plantation tree species in China. However, the genes controlling drought tolerance in this species have not been identified or characterized. Here, we conducted differential expression analyses and identified a number of genes that were up- or downregulated in P. hopeiensis during water stress. To the best of our knowledge, this is the first comprehensive study of differentially expressed genes in water-stressed P. hopeiensis. Results: Using the cDNA-AFLP detection technique, we used 256 primer combinations to identify differentially expressed genes in P. hopeiensis during water stress. In total, 415 transcript derived-fragments (TDFs) were obtained from 10× deep sequencing of 473 selected TDFs. Of the 415 TDFs, 412 were annotated by BLAST searches against various databases. The majority of these genes encoded products involved in ion transport and compartmentalization, cell division, metabolism, and protein synthesis. The TDFs were clustered into 12 groups on the basis of their expression patterns. Of the 415 reliable TDFs, the sequences of 35 were homologous to genes that play roles in short or long-term resistance to drought stress. Some genes were further selected for validation of cDNA-AFLP expression patterns using real-time PCR analyses. The results confirmed the expression patterns that were detected using the cDNA-AFLP technique. Conclusion: The cDNA-AFLP technique is an effective and powerful tool for identifying candidate genes that are differentially expressed under water stress. We demonstrated that 415 TDFs were differentially expressed in water-stressed poplar. The products of these genes are involved in various biological processes in the drought response of poplar. The results of this study will aid in the identification of candidate genes of future experiments aimed at understanding this response of poplar. [ABSTRACT FROM AUTHOR]

In the Labrador Sea, the coldest and freshest North Atlantic basin south of the Greenland-Iceland-Scotland Ridge, wintertime surface heat losses result in the formation of dense waters that play an important role in ventilating the deep ocean and driving the global ocean overturning circulation. In the winter of 2020, the central Labrador Sea lost more heat through surface cooling than in the previous winter. However, the surface heat loss remained nearnormal for a third straight year, contrasting a 27-year record high in 2015 and above-normal losses in 2016 and 2017. The 2020 winter (Dec-Mar) North Atlantic Oscillation (NAO) index was above normal and the highest after reaching its record high in 2015. However, the sea level pressure pattern was not associated with strong westerly winds along the Labrador coast. This led to, respectively, near-normal and above-normal winter and spring air temperatures in the Labrador Basin domain. Both winter and spring sea surface temperatures in the Labrador Basin were above normal. Winter sea ice extent was below normal in the Davis Strait, Northern Labrador Shelf, and Labrador Shelf regions. Spring sea ice extent was also below normal in all three regions. With respect to temperature anomalies averaged annually over the central Labrador Sea, the upper 100 m layer was the coldest in the 2002-2020 period in 2015 and 2018. After 2018, this layer attained above-normal annual temperatures in 2019-2020, reaching a 2011-2020 temperature high in 2019, then slightly cooling yet remaining above normal through 2020. The intermediate, 200-2000 m, layer of the Labrador Sea started to cool immediately after hitting a record warm point of the 1972-2020 period in 2011. This cooling trend was mainly driven by strengthening and progressively deepening winter convection in 2012 and during 2014-2018. The key factor that contributed to the recurrent deepening of convective mixing in the three straight winters following the winter of 2015 was not as much airsea heat exchange as it was the water column preconditioning set by convective mixing in the previous years. Such multiyear persistence of deepening winter convection, continuing through the winter of 2018 when it exceeded 2000 m in depth, resulted in the most voluminous, densest, and deepest formation of Labrador Sea Water since 1994. The situation changed in 2019, with the depth of winter convection largely ceasing to exceed 1400 m in that and the following two years. The intermediate layer has been warming since 2019 with the seawater density trend eventually reversing to negative. Even though wintertime mixing reached marginally deeper in 2020 (by 100 m or so), and the intermediate layer slightly cooled, the negative density trend prevailed. Between 2018 and 2020, the annual mean intermediate layer density reduced by about 0.01 kg/m3. Overall, the changes in the depth of winter convection and intermediate layer properties between these years imply that the effect of the water column preconditioning on winter convection has weakened since 2018. Vertical distributions of dissolved oxygen and chlorofluorocarbons (CFCs) - CFCs, industrially Freons, are the anthropogenic gases that are commonly used as tracers of convectively-formed water masses spreading in the ocean - in the central Labrador Sea, based on quality controlled drift-corrected measurements assembled since 1990, follow very closely the multiyear events of recurrently persistent renewal of dense deep Labrador Sea Water in the Atlantic Ocean. Bedford Institute of Oceanography North Atlantic model simulations suggest that the transport of the Labrador Current generally decreased between 1995 and 2014, increased between 2014 and 2019, and slightly decreased in 2020. The Atlantic meridional overturning circulation index based on this model demonstrates a general weakening trend from the mid-1990s until 2004, then slight strengthening lasting until 2011, then weakening again until the overturning weakest point was reached in 2019. The overturning circulation started to strengthen in 2020, but it is too early to associate this shortterm increase with a reversal of the current negative trend in the Atlantic meridional overturning circulation. [ABSTRACT FROM AUTHOR]

In the Labrador Sea, the coldest and freshest North Atlantic basin south of the Greenland-Iceland-Scotland Ridge, wintertime surface heat losses result in the formation of dense waters that play an important role in ventilating the deep ocean and driving the global ocean overturning circulation. In the winter of 2018-2019, the central Labrador Sea gave out less heat through its surface than in any of the five preceding winters. The recent reduction in the seasonal cooling of the Labrador Sea contrasts a 25-year record high winter heat lost in 2015. The winter (December-March) North Atlantic Ocillation (NAO) index was moderately positive in 2019. However, atmospheric circulation associated with a low-atmospheric-pressure anomaly in the Labrador Sea in winter resulted in above-normal air temperatures in the northern and central Labrador Sea. Sea-surface temperatures were near-normal in winter and above-normal in spring. Sea-ice-extent anomalies in winter and spring were generally negative, except for a near-normal winter anomaly on the central Labrador Shelf. With respect to annually-averaged, temperature-anomaly values, in 2018, the upper 100 m layer of the central Labrador Sea was the coldest since 2000. However, between 2018 and 2019, this layer warmed by 0.5 °C. The intermediate (200-2,000 m) layer cooled between 2011 (the layer's warmest year since 1972) and 2018. This cooling trend can be associated with persistent deepening of winter convection over the same time period. The key factor that has contributed to the recurrent deepening of convective mixing in the three winters following the winter of 2015 was not as much air-sea heat exchange as it was the water-column preconditioning caused by convective mixing in the previous years. Such multiyear persistence of deepening winter convection, which lasted until the winter of 2018-2019 and exceeded 2,000 m in depth, has resulted in the most voluminous, densest, and deepest formation of Labrador Sea Water since 1994. In the winter of 2018-2019, the situation has, however, changed with winter convection not generally exceeding 1,200 m and the intermediate layer warming slightly but enough to reverse the seawater-density trend. Between 2018 and 2019, the annual mean-intermediatelayer density reduced by 0.007 kg/m³. Overall, the changes in the depth of winter convection and intermediate-layer properties between these years imply that the effect of the water-column preconditioning on winter convection has weakened since 2018. Bedford Institute of Oceanography North Atlantic Model simulations suggest that the transport of the Labrador Current decreased between 1995 and 2014, but has since increased slightly. The Atlantic Meridional Overturning Circulation index based on this model demonstrates a general weakening trend since mid-1990s, and continued weakening in recent years is present in this model hindcast. [ABSTRACT FROM AUTHOR]

In the Labrador Sea, wintertime surface heat losses result in the formation of dense waters that play an important role in ventilating the deep ocean and driving the global ocean overturning circulation. In the winter of 2017-18, as in the previous two winters, the subpolar North Atlantic experienced below-average (2017-18) to average (2015-16 and 2016-17) surface heat losses, which were significantly lower than the 2014-15 winter heat loss, that was the highest since 1993-94. The winter (December-March) North Atlantic Oscillation (NAO) index in 2017-18, and winter ocean-atmosphere heat fluxes, in the central Labrador Sea, were near their long-term average values. However, atmospheric circulation, associated with a high atmospheric pressure anomaly extending throughout the Labrador Sea in winter, resulted in above-normal air and sea surface temperatures in the western Labrador Sea, and below-normal temperatures in the northeastern Labrador Sea. For sea surface temperature, these conditions persisted into the spring season, appearing to propagate cyclonically. Sea ice concentration anomalies in February and March, 2018, were generally negative in the western Labrador Sea, and positive in the northeastern Labrador Sea, consistent with the atmospheric circulation and air temperature anomalies. The upper 100 m layer of the central Labrador Sea has been cooling since 2010. However, the intermediate (200-2000 m) layer only started to cool after 2011, which was the layer's warmest year during 1972-2018. This cooling was mainly caused by ongoing deepening of winter convection. Indeed, despite a reduction in the cumulative heat losses from the sea surface after 2014-15, the depth of winter convection continued to increase in the three winters that followed. This is mainly due to the water column preconditioning caused by convective mixing in the previous years. The multiyear persistence of deepening winter convection (eventually exceeding 2000 m in depth) has resulted in the most voluminous, densest and deepest formation of Labrador Sea Water since 1994. Bedford Institute of Oceanography North Atlantic model simulations suggest that the transport of the Labrador Current decreased between 1995 and 2014, but has since increased slightly. [ABSTRACT FROM AUTHOR]

The transplanting mechanism is the core working part of a rice transplanter, and its working cycle includes the stages of picking, transporting, planting, and returning. Aimed at the problems of poor working precision, poor trajectory and attitude, and low operating efficiency of the existing transplanting mechanism of rice transplanters, a transplanting mechanism with three planting arms constrained by differential noncircular gear trains was designed to avoid the side gap accumulation caused by unequal multistage speed transmission. The movement of the 2R open-chain mechanism was constrained by a differential noncircular gear train so that the connecting rod could realize the trajectory and attitude required for rice transplanting. Based on the unequal speed transmission of differential noncircular gear trains, a kinematic model of the transplanting mechanism with three planting arms was established, and the optimal software design of the transplanting mechanism was developed in a visual programming environment. Based on the agronomic requirements for rice transplanting, the optimization design targets of the transplanting mechanism were customized, the functional relationship between the optimization targets and parameters was established, and the optimization targets were embedded into the optimal software design. Through parameter optimization, a set of mechanism parameters meeting the requirements of the trajectory and attitude for rice transplanting were obtained, and the structural design of the transplanting mechanism was completed. Virtual simulation experiments and bench experiments with the transplanting mechanism with three planting arms constrained by differential noncircular gear trains showed that the transplanting mechanism accurately realized the trajectory and attitude required for rice transplanting. [ABSTRACT FROM AUTHOR]

The article reports on the multispecies biogeographic cline associated with climatic gradient and seasonal temperature in northwest Atlantic. Topics include the macroecological phenomenon demonstrated by the genetic break among various marine species, the association between the marine population distribution and the climate forecast and habitat suitability, and the effect of cryptic diversity associated with climate variation on how the species response to climate change.

Previous study has verified the polysaccharide from the fruiting body ofPleurotus eryngii(PEPE) is capable of decreasing the lipid content in both of cell-line and mouse model. However, little is known about underlying mechanisms and whether this bioactive polysaccharide exists in submerged culture. Here, we verified the excreted polysaccharides EP and EP-1 from submersion culture ofP. eryngiihave the remarkable inhibitory effects on lipid accumulation in macrophage-derived foam cells. Structure analysis indicates EP-1 consists ofd-types of glucose, galactose and mannose with the main β(1→3)-glucan glycosidic linkage branched at O-6 by α-d-glucose while EP digested by β-1,3-glucanase fails to decrease the lipid accumulation, suggesting that the special structure is essential for its function. Expression analysis suggests that EP is able to cause the down-regulation of the scavenger receptor-CD36 on both transcription and protein levels. Most importantly, EP can be obtained by fermentation in a mass-production. [ABSTRACT FROM AUTHOR]