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Planetary gear train is mainly used for power transmission, so it is of great significance to study its self-locking and efficiency. In this study, the self-locking analysis and efficiency maximization design of a 3K-H planetary gear train are carried out. Firstly, the efficiency of the positive and negative mechanism of the gear train is calculated using the transmission ratio method. Then, a unified formula for the efficiency of the planetary gear train is summarized. Furthermore, the efficiency curve is drawn by Matlab. Next, the trend of efficiency change of the planetary gear train and the conditions for realizing self-locking are analyzed. Finally, how to maximize the efficiency of the opposite mechanism under the condition of self-locking is studied.

Container transportation is an important mode of international trade logistics in the world today, and its changes will seriously affect the development of the international market. For example, the COVID-19 pandemic has added a huge drag to global container logistics. Therefore, the accurate forecasting of container throughput can make a significant contribution to stakeholders who want to develop more accurate operational strategies and reduce costs. However, the current research on port container throughput forecasting mainly focuses on proposing more innovative forecasting methods on a single time series, but lacks the comparison of the performance of different basic models in the same time series and different time series. This study uses nine methods to forecast the historical throughput of the world's top 20 container ports and compares the results within and between methods. The main findings of this study are as follows. First, GRU is a method that can produce more accurate results (0.54–2.27 MAPE and 7.62–112.48 RMSE) with higher probability (85% for MAPE and 75% for RMSE) when constructing container throughput forecasting models. Secondly, NM can be used for rapid and simple container throughput estimation when computing equipment and services are not available. Thirdly, the average accuracy of machine learning forecasting methods is higher than that of traditional methods, but the accuracy of individual machine learning forecasting methods may not be higher than that of the best conventional traditional methods. [ABSTRACT FROM AUTHOR]

Acute myeloid leukemia (AML) with nucleophosmin 1 (NPM1) mutations exhibits distinct biological and clinical features, accounting for approximately one-third of AML. Recently, the N 6-methyladenosine (m6A) RNA modification has emerged as a new epigenetic modification to contribute to tumorigenesis and development. However, there is limited knowledge on the role of m6A modifications in NPM1-mutated AML. In this study, the decreased m6A level was first detected and high expression of fat mass and obesity-associated protein (FTO) was responsible for the m6A suppression in NPM1-mutated AML. FTO upregulation was partially induced by NPM1 mutation type A (NPM1-mA) through impeding the proteasome pathway. Importantly, FTO promoted leukemic cell survival by facilitating cell cycle and inhibiting cell apoptosis. Mechanistic investigations demonstrated that FTO depended on its m6A RNA demethylase activity to activate PDGFRB/ERK signaling axis. Our findings indicate that FTO-mediated m6A demethylation plays an oncogenic role in NPM1-mutated AML and provide a new layer of epigenetic insight for future treatments of this distinctly leukemic entity. [ABSTRACT FROM AUTHOR]

High-rise buildings have a significant impact on the surrounding environment. Building-integrated solar water heating (SWH) systems are effective ways to use renewable energy in buildings. Impediments, such as security concerns, aesthetics and functionality, make it difficult to apply SWH systems in high-rise buildings. At present, only China uses SWH systems on a large scale in such buildings. What are China's experiences and lessons learned in applying SWH systems in high-rises? Are these experiences scalable to other countries? This study used a combination of field investigation, literature review and case study to summarize 36 systems that had been in operation for 1–14 years. System types, collector types, installation methods, types of auxiliary heat sources, economic performance and various basic principles were summarized. The economic performance of SWH systems in high-rise buildings was analyzed and verified by a case study in Shanghai. The results show that the installation of SWH systems in high-rise buildings is feasible and reliable. Individual household systems (61%) were more popular than centralized systems (25%) and hybrid systems account (14%). The average area of solar collectors per household was 2.17 m2/household, the average design solar fraction was 52%. Flat plate solar collectors (53%) was the most commonly used collector, while electric heating elements (89%) were the most common auxiliary heat sources for SWH systems, followed by gas water heaters and air source heat pumps. The cost of SWH systems per m2 of a building area was between 22 CNY/m2 to 75 CNY/m2. China's unique practical experience gives a reference for other countries in their efforts to make high-rise buildings more sustainable. [ABSTRACT FROM AUTHOR]

Silver powder, as the primary component of solar silver paste, significantly influences various aspects of the paste's performance, including printing, sintering, and conductivity. This study reveals that, beyond the shape and size of the silver powders, their microstructure is a critical factor influencing the performance of both silver powders and silver pastes in solar cell applications. The growth process leads to the formation of either polycrystalline aggregated silver powder or crystal growth silver powder. Analyzing the performance characteristics of these different microstructures provides guidance for selecting silver powders for silver pastes at different sintering temperatures. Polycrystalline aggregated silver powder exhibits higher sintering activity, with a sintering initiation temperature around 450 °C. The resulting silver paste, sintered at 750 °C, demonstrates a low sheet resistance of 2.92 mΩ/sq and high adhesion of 2.13 N. This silver powder is suitable for formulating silver pastes with lower sintering temperatures. The solar cell electrode grid lines have a high aspect ratio of 0.37, showing poor uniformity. However, due to the high sintering activity of the silver powder, the glass layer dissolves and deposits more silver, resulting in excellent conductivity, a low contact resistance of the silver electrode, a low series resistance of the solar cell of 1.23 mΩ, and a high photoelectric conversion efficiency of 23.16%. Crystal growth silver powder exhibits the highest tap density of 5.52 g/cm3. The corresponding silver paste shows improved densification upon sintering, especially at 840 °C, yielding a sheet resistance of 2.56 mΩ/sq and adhesion of 3.05 N. This silver powder is suitable for formulating silver pastes with higher sintering temperatures. The solar cell electrode grid lines are uniform with the highest aspect ratio of 0.40, resulting in a smaller shading area, a high fill factor of 81.59%, and a slightly higher photoelectric conversion efficiency of 23.17% compared to the polycrystalline aggregated silver powder. [ABSTRACT FROM AUTHOR]

Background: Metabotropic glutamate receptor 5 (mGluR5) is involved in regulating integrative brain function and synaptic transmission. Aberrant mGluR5 signaling and relevant synaptic failure play a key role in the initial pathophysiological mechanism of Alzheimer's disease (AD). The study aims to investigate the association between mGluR5 availability and AD's biomarkers and cognitive function. Methods: We examined 35 individuals with mGluR5 tracer [18F]PSS232 to assess mGluR5 availability, and with [18F]Florbetapir PET to assess global amyloid deposition, and [18F]FDG PET to assess glucose metabolism. The plasma neurofilament light (NfL) and p-tau181 levels in a subset of individuals were measured (n = 27). The difference in mGluR5 availability between the AD and normal control (NC) groups was explored. The associations of mGluR5 availability with amyloid deposition, glucose metabolism, gray matter volume (GMV), neuropsychological assessment scores, and plasma biomarkers were analyzed. Results: The mGluR5 availability was significantly reduced in AD patients' hippocampus and parahippocampal gyrus compared to NCs. Global amyloid deposition was positively associated with mGluR5 availability in the AD group and reversely associated in the NC group. The mGluR5 availability was positively correlated with regional glucose metabolism in the overall and stratified analyses. The availability of mGluR5 in the hippocampus and parahippocampal gyrus demonstrated a strong relationship with the GMV of the medial temporal lobe, plasma p-tau181 or NfL levels, and global cognitive performance. Conclusions: [18F]PSS232 PET can quantify the changes of mGluR5 availability in the progression of AD. mGluR5 availability correlated not only with neuropathological biomarkers of AD but also with neurodegenerative biomarkers and cognitive performance. mGluR5 may be a novel neurodegenerative biomarker, and whether mGluR5 could be a potential therapeutic target for AD needs to be further studied. [ABSTRACT FROM AUTHOR]

Polygonatum cyrtonema is a perennial plant, and it has long been used in traditional Chinese medicine for food and medicine. The medicinal part of P.cyrtonema is the rhizome; however, the aerial part has not been studied. To understand the effect of the topping of aerial parts on the yield and chemical components of rhizomes, as well as the chemical constituents, antioxidant, and in vitro hypoglycemic activities of the aerial stem, leave, and flower parts of P.cyrtonema, the present study was conducted. The results showed that compared to the control (CK) treatment, the topping of the aerial part increased rhizome weight gain coefficient (3.43) and the total saponin content (37.60 mg/g) significantly (P<0.01) than the CK treatment. The contents of total phenols and total flavonoids in PCL and PCF were significantly (P<0.01) higher than those in rhizomes; however, the polysaccharide content (10.47%) in PCR (whole rhizome) was higher than that in PCS (3.65%), PCL (5.99%), and PCF (4.76%) content. The protein and amino acid contents in PCS, PCL, and PCF were higher than those in rhizomes. The protein and amino acid contents in PCS, PCL, and PCF were higher than those in rhizomes. PCS, PCL, and PCF showed strong antioxidant activity (DPPH, ·OH, ABTS, and FRAP), which were better than traditional medicinal parts (the rhizome).In vitro hypoglycemic results showed that PCS, PCL, and PCF had certain inhibitory activities on α-amylase and α-glucosidase (66.25% and 52.81%), which were close to the hypoglycemic activity of rhizomes (67.96% and 52.22%). The leaf extracts also showed better inhibitory activity. To sum up, the topping measures can improve yield and total saponin content of the rhizomes from P.cyrtonema, which can be applied to improve production. The stems, leaves, and flowers had a much stronger antioxidant and hypoglycemic activities and higher the total polyphenols, flavonoids, proteins, and amino acid content. Therefore, stems, leaves, and flowers of Polygonatum can be fully developed according to different needs. they are typically used in animal feed, food storage and cosmetics. [ABSTRACT FROM AUTHOR]

Frequent geological hazards in Pingguo City, Guangxi Province, seriously restrict the engineering construction in this area. Through the remote sensing interpretation and field investigation, 251 hillslope geological hazards, including 189 collapses and 62 landslides in Pingguo City are determined. All hazard points are randomly split into two subsets with 80% (200) and 20% (51) respectively for training and validation purposes. In addition, an equal number of non-hazard points were randomly selected from the hazard-free areas and then divided into a training dataset and a validation dataset. The hazard point is denoted as 1 and the non-hazard point is denoted as 0. Then, based on the geological environment conditions of Pingguo City, nine factors including elevation, slope angle, slope aspect, curvature, engineering geology groups, distance from faults, soil thickness, distance from rivers and rainfall are selected as hazard evaluation factors. Elevation, slope angle, slope aspect and curvature are topographic factors, which are produced from Advanced Land Observing Satellite (ALOS) digital surface model (DSM) with a resolution of 12.5 m. Distance from rivers is one of hydrological variables, also produced from the ALOS DSM. Engineering geology groups and distance from faults are geological factors, which are produced from a geological map at a scale of 1:200,000 provided by the China Geological Survey. Soil thickness is one of the factors related to land use, which is derived from domestic high resolutions remote sensing data such as Gaofen No.2 and Beijing No.2. Rainfall is an environmental factor, which is collected from the China Meteorological Administration. All relevant factors are converted into raster format with a 12.5-m resolution of ArcGIS software. Among these nine factors, engineering geology group is a categorical factor, whereas the other factors are continuous factors. In this study, continuous factors are reclassified into categorical factors based on natural breaks or equal interval methods. The tolerance (TOL) and variance inflation factor (VIF) are used to detect multicollinearity of all the factors. Generally, a VIF of less than 10 or a TOL of more than 0.1 indicates that all the factors are independent. Then, combined with the advantages of information value (IV) and multi-layer perceptron classifier (MLPC), the coupling model of IV and MLPC is used to evaluate the susceptibility of hillslope geo-hazard in Pingguo City, and the results are classified into five classes: very low, low, moderate, high, and very high. Finally, the receiver operating characteristic curve (ROC) and the area under the ROC curve are applied to carry out accuracy verification of the model. The main conclusions include: (i) Rainfall has the highest VIF value (1.163) and the lowest TOL value (0.86), both of which do not exceed the critical threshold values (TOL>0.1 or VIF<10). Thus, there are no severe collinearity problems among the 9 conditioning factors. (ii) The information values of the factor classes show that certain classes are conducive to the occurrence of hazards. The factor classes mostly prone to the occurrence of hazards are the elevation with 250-350 m, slope angle with 40°-50°, south slope, curvature less than -0.05, limestone and dolomite, 0-500 m from the faults, soil thickness with 0-1m, the area 0-250 m from the rivers and rainfall with 1,373-1,428 mm. (iii) The zoning map of hillslope geo-hazard susceptibility in Pingguo City shows that the areas with very high, high, moderate, low and very low susceptibility respectively account for 25.39%, 3.49%, 4.34%, 30.54% and 36.24% of the total area of the city. The areas with very high susceptibility are mainly distributed in the junction of steep mountains and plains, such as Liming town, Tonglao town and Bangwei town in the north of the study area, Haicheng town, Tonglao town and Pozao town in the middle and Xin'an town in the south. The hillslope geo-hazards in these five susceptible areas cover proportions of 64.54%, 8.37%, 1.59%, 21.91%, and 3.59%, respectively, which indicates that the evaluation results of hazard susceptibility are highly consistent with the distribution of historical collapse and landslides, and the mapping results of hazard susceptibility are reliable and accurate. (iv) The frequency ratio of each susceptibility zone can be obtained by calculating the ratio of hazard point proportion and area proportion of each susceptibility class. The frequency ratio increases from the very low susceptibility area to the very high susceptibility area, which indicates that the coupling model can effectively determine the different susceptibility levels in the study area. (v) The performance of the model is comprehensively compared through the AUC and ROC curves with validation datasets. The AUC value for the IV-MLPC model is 0.809, showing that the model exhibits a satisfactory performance (AUC>0.8) in collapse and landslide spatial prediction. The research results can provide a scientific basis for the risk assessment and disaster prevention of collapse and landslide in the study area. [ABSTRACT FROM AUTHOR]