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【Objective】 Water flow in pumps is modeled using computational fluid dynamics (CFD). However, the impact of turbulence model on simulation accuracy remains unexplored. This study aims to address this gap. 【Method】 We simulated axial water flow in a pump using three turbulent models: the Standard k-ε, RNG k-ε and SST k-ω models. We compared the simulated results with experimental results and analyzed the internal flow fields simulated by different turbulence models. 【Result】 At steady flow state, the head curves simulated by all three turbulence models were consistent with the experimental curves. Under forward and reverse flow braking conditions, the head calculated by the Standard k-ε and SST k-ω model was close to or slightly higher than that calculated by the RNG k-ε model. Compared to the RNG k-ε model, the Standard k-ε and SST k-ω models reduced the maximum error of calculated head by 0.13 m and 0.22 m, and average error by 0.55 m and 0.48 m, respectively. Under low water flow condition in the forward pump, the maximum and average error of the calculated head by the standard k-ε model were the least; compared to the RNG k-ε and SST k-ω model, it reduced the maximum error of the calculated head by 1.19 m and 0.96 m, and the average error by 0.56 m and 0.68 m, respectively. Under reverse downstream braking conditions, the SST k-ω model was most accurate; compared to the Standard k-ε and RNG k-ε model, it reduced the maximum errors of the calculated head by1.08 m and 1.63 m, and average errors by 0.6 m and 0.9 m, respectively. Under the reverse pump condition, the Standard k-ε was most accurate; compared to the RNG k-ε and SST k-ω models, it reduced the maximum errors of the calculated head by 0.65 m and 0.74 m, and average errors by 0.34 m and 0.44 m, respectively. For other conditions, including positive rotating pump, positive rotating downstream braking, positive rotating and reverse rotating turbine, the simulated internal flow field in the pump was smooth, the simulated external characteristics were close to experimental observations, and simulated results of all three models were similar. 【Conclusion】 The accuracy of turbulence models for simulating axial water flow in pumps depends on operating conditions. Our results provide insights into selecting appropriate turbulence model for simulating water flow in pumps.

Cushing′s syndrome (CS), an endocrine disorder resulting from excessive glucocorticoid secretion by the adrenal cortex, poses significant challenges to both diagnosis and treatment. The diagnostic process involves comprehensive evaluation, combining laboratory tests and imaging studies for screening, qualification, and localization. Surgical intervention remains the primary treatment approach, although pharmacological therapy also plays a crucial role. With an increasing understanding of the pathogenesis of CS, more potential targets for orphan drug development have been discovered. This article summarizes the current status of diagnosis and treatment for CS and provides an outlook on future research directions.

[Objective] Regional carbon storage is closely related to land use. Under the goal of “carbon peaking and carbon neutrality”, researches about land use change calculations in significant regions play an important role on coordinating and optimizing regional land use patterns, improving the future carbon sequestration potential of regional ecosystems. [Methods] Taking Western Sichuan Plateau as the study area this paper predicts land use changes under different scenarios from 2020 to 2030, and estimates regional carbon storage changes by using revised land use carbon density data and land use data in 2000, 2010 and 2020. [Results] (1) From 2000 to 2020, grassland gradually decreased from 65.20% to 63.65%, forest continuously expanded from 31.73% to 32.92%, unused land firstly decreased and then increased and the net increase rate is 0.57%, water area and farmland firstly increased and then decreased and their net decrease rate is 0.11% and 0.11%, wetlands continued to increase by 0.07%; The carbon reserves of the study area in 2000, 2010 and 2020 were 24.26×108, 24.29×108, 24.27×108 t, showing a trend of first increasing and then decreasing.(2) Carbon storage reduced 3.19×105 t under natural development scenario. Under farmland protection scenario, ecological protection scenario, and farmland ecological joint protection scenario, their carbon sequestration will be respectively 4.29×106, 9.72×106, 9.60×106 t. [Conclusion] Reversing the increasing trend of unused land, continuing to steadily implement ecological protection policies with maintaining the cultivated land area, improving the carbon sequestration potential, and helping the Western Sichuan Plateau become an important “carbon sink” area should become the key points of land spatial planning and control on the Western Sichuan Plateau.

Background: Osteoarthritis (OA) is a common degenerative joint disease with significant negative impact on the quality of life. It has been reported that abnormal upregulation of β-catenin signaling could lead to OA development; however, the upstream regulatory mechanisms of β-catenin signaling have not been determined. Methods: Primary rat chondrocytes and ATDC5 chondrocyte cell line were stimulated with AKT2 and treated with or without metformin, an adenosine 5′-monophosphate-activated protein kinase (AMPK) activator. Westerrn blot analysis, luciferase reporter assay and immunofluorescent (IF) staining were performed to examine changes in β-cateninS552 phosphorylation and β-catenin nuclear translocation in ATDC5 cells and in primary chondrocytes. Results: We found that metformin inhibited β-cateninS552 phosphorylation in ATDC5 cells and in primary chondrocytes in a time-dependent manner. Metformin inhibited β-catenin nuclear translocation and β-catenin reporter activity. In addition, metformin also attenuated the expression of β-catenin downstream target genes. We also demonstrated that metformin inhibited β-cateninS552 phosphorylation in articular cartilage in mice. Conclusion: These findings suggest that metformin may exert its chondro-protective effect at least in part through the inhibition of β-catenin signaling in chondrocytes. The translational potential of this article: This study demonstrated the interaction between AMPK and β-catenin signaling in chondrocytes and defined novel molecular targets for the treatment of OA disease.

In this paper, zircon SHRIMP U-Pb geochronology, petrology, mineral chemistry, petrogeochemistry, Sm-Nd and Lu-Hf isotopes were studied for the eastern part of the Dupangling pluton, which is located at the western section of Nanling at the junction of Hunan and Guangxi provinces. The zircon SHRIMP U-Pb dating results show that the age of coarse-to-medium-grained porphyritic biotite monzogranite is 215.6±2.1 Ma, medium-grained porphyritic biotite monzogranite 220.5±1.8 Ma, medium-grained rapakivi biotite monzogranite 222.8±1.5 Ma. Combined with the age of fine-grained muscovite monzogranite as 209.7±3.1 Ma obtained in the previous research, it is suggested that the emplacement time ranges from 222.8 Ma to 209.7 Ma, and the pluton is derived from the Indosinian magmatic activity rather than the Yanshanian as previously thought. The mineral-chemical characteristics of rapakivi K-feldspar and biotite phenocryst indicate that the magma temperature, pressure and composition have gone through fluctuation during the formation process, and biotite phenocryst was formed by multiple melting under the underplating by basaltic magma in this area. The Dupangling biotite monzogranites have higher contents of SiO2 and K2O+Na2O, A/CNK value ranges between 1.02 and 1.39 and Rittman index (δ) between 0.93 and 2.18, belonging to the peraluminous calc-alkaline. Moreover, these monzogranites are enriched in REE, Rb, Th and U with higher content of HFSE (Nb, Y and Ga), depleted in Ba, Sr and Eu with higher ratios of TFeO/MgO and Ga/Al, showing the characterisitics of A-type granite. The isotope εNd(t) value ranges from -8.74 to -8.13, and the T2DM value from 1.71 to 1.66 Ga; the zircon isotope εHf(t) value ranges from -14.1 to -1.4, and the T2DM value from 2.14 to 1.34 Ga. It reveals that the Dupangling biotite monzogranites mainly originated from the partial melting of ancient crustal materials and were mixed with a certain degree of depleted mantle materials. The metamorphic peak period of the Indosinian movement is from 258 Ma to 243 Ma. South China was in an extensional tectonic setting after 233 Ma and mantle-derived basalt magma was in a wide range of underplating, which caused the crustal material remelting to form the Dupangling Indosinian aluminous A-type granite (rapakiwi granite) under an extensional background.

Taking the dense sandstone gas reservoirs of Shibang Group and Shanxi Group in Dongsheng area of Ordos Basin as an example, based on the characterization of the dense sandstone reservoirs in the study area in terms of petrological features, pore structure and diagenesis, we carried out real sandstone microscopic seepage experiments to analyze the gas-water seepage law and fluid storage state of different types of reservoirs, and systematically evaluated the efficiency of gas-water repulsion from the dense sandstone reservoirs and the microscopic influencing factors. The results show that the study area has strong non-homogeneity and different degrees of pore density, so a variety of fluid transportation channels are formed, and different transportation channels represent different types of evacuation. When the residual pore space and dense sandstone microporous space exist at the same time, gas and water are mainly transported along the residual pore space, and the microporous space of the dense particles almost does not enter; gas and water transport is very much affected by permeability, and the transport resistance will increase with the decrease of permeability; the pressure has a certain effect on the efficiency of the replacement, but it can only improve the efficiency of the replacement to a certain extent; the fluids in the process of rock transport, there will be varying degrees of bubbles stuck off In the process of fluid transport in the rock, there will be different degrees of bubble jamming phenomenon, resulting in the transport needs to overcome a large capillary resistance, which greatly increases the replacement pressure; for the low-permeability sandstones in Hangjinqi area, the good homogeneity of the pore structure of the conductor does not mean that the transport effect is good, in the area of the conductor pore space is strongly developed, the gas-water transport will form an advantageous channel, and its transport effect is better.

Objective To establish a differentiated training program for ophthalmic postdoctoral students and explore its teaching effects in the Department of Ophthalmology, Peking Union Medical College Hospital. Methods All of the in-training clinical postdocs were evaluated. The differentiated training program and the stepwise surgical training system were established based upon different education backgrounds. The results of the theoretical examination of clinical postdocs and other students were analyzed by horizontal comparison, and the development of theory and skill levels was analyzed by longitudinal comparison. The progress of postdocs in the past three years was also evaluated through the competence model in six dimensions of professionalism, skills of communication and cooperation, patient care, knowledge and skills, teaching ability, and lifelong learning. Results The median scores of theoretical examination of the first- and third-year postdocs were higher than those of other students, and the levels of theory and skill of the postdocs improved year by year. The postdocs effectively developed in all six dimensions of the competence model in the third year. Conclusion The differentiated training program can effectively improve the integrated skills of postdocs and creates favorable conditions for the cultivation of high-level medical talents.

Discharge of acid mine drainage (AMD) from abandoned coal mines of the YuDong catchment in Kaili City, Guizhou Province, China, has severely damaged local ecological environments. In this study, a laboratory-scale dispersed alkaline substrate (DAS) was studied for the treatment of simulated AMD. The experimental conditions and reaction mechanisms were preliminarily explored. The treatment effect and variation law of vertical effluent water quality of the experimental conditions were thoroughly analysed. The results indicated that small-sized limestone (diameter 5–7 mm) having a 20:1 mixture ratio with shavings and minimum HRT of 20 hours result in increasing effluent pH from 3.5 to 6.6, achieving 66.2% and 99.1% removal of Fe and Al, respectively. There were obvious differences in each reaction layer for the removal of various pollutants from AMD along the depth by DAS, the main reaction zone was first 20–30 cm of the reaction column. The removal process of metal ions and sulfate was accompanied by bio-mineralization reaction. This test provided a valuable support for the local practical engineering applications, enriched the AMD processing technology experimental cases, and provided reference for the treatment technology of similar polluted areas. HIGHLIGHTS A dispersed alkaline substrate was designed to treat the acid mine drainage from abandoned coal mines of YuDong valley, which provides a reference for the further design of site device and other similar contaminated areas.; Combining the physical and chemical parameters of the effluent, and mineralogical characterization of the filler along with the microbial diversity of the system, the mechanism of DAS treatment of AMD was analyzed.; Under this experiment conditions, DAS can raise the effluent pH to 6.6, and the average removal rate of Fe and Al was 66.2% and 99.1%, respectively. Daily decrease rate of Fe was 16∼18 g/m2/d.;

Objective To investigate the current situation of surgical teaching for residents of Chinese ophthalmology. Methods Questionnaires were collected from ophthalmology teaching hospitals and standardized training centers across China. Results A total of 238 ophthalmologists were enrolled, of which 194(81.51%) participated in surgical teaching. Cataract surgery was most frequently taught (51.03%). The median number (interquartile range) of surgical operation that residents were scheduled to observe was 135(450), the number of operations that residents performed at some steps was 30(50), and the number of surgical operation that residents may perform independently was 5(19). The three tasks that teachers considered most difficult were to establish a good Wet Lab program (56.19%), the prevention of complications (51.55%) and the overall work of surgical teaching (50.52%). The response with the highest proportion of “very difficult” was to convince patients about the involvement of residents in the treatment(36.60%). The most difficult step in cataract surgery teaching was nucleus fragmentation. Conclusions Although residents' surgical training is widely carried out in China, many difficulties still exist. The number of the operation that can independently be completed by the residents is relatively low.

The mid-lower reaches of the Hanjiang River Basin, located in the core of economic development in Hubei Province, is an integral part of the Yangtze River Economic Belt. In recent years, the watershed ecosystem has become more sensitive to climate changes and human activities, thus affecting the regional vegetation cover. To maintain a stable watershed ecosystem, it is critical to analyze and evaluate the vegetation change and its response to temperature, precipitation, and human activities in this region. This study, based on the trend analysis, partial correlation analysis, and residual analysis, evaluated the change characteristics of vegetation cover as well as the corresponding driving factors in the basin from 2001 to 2015. The results showed that (1) the overall spatial pattern of vegetation cover in the study area was “high in the west and north, lower on both sides of Hanjiang River, and lowest in the center and southeast,” and the pattern changed parabolically with the increasing elevation. (2) Over the 15 years, vegetation cover in the basin showed an increasing trend, and the increased and decreased areas were 90.72 and 9.23%, respectively. (3) The response of vegetation cover to climatic factors varies greatly depending on the increasing elevation. That is, the lag effect under the impact of temperature disappeared gradually, while it became more evident under the impact of precipitation. (4) On the whole, human activities had a positive effect on the regional vegetation cover. The negative effect in the areas around the Nanyang Basin and the positive effect in most parts of the Jianghan Plain were gradually decreased.

Objective To investigate expression changes of phospholipase C-γ1 (PLCγ1)/inositol triphosphate receptor (IP3R)/calmodulin-dependent kinase Ⅱ (CaMKⅡ) and density of dendritic spine in the hippocampus of autism model mice induced by sodium valproate (VPA). Methods Pregnant C57 mouse was given intraperitoneal injection of 300 mg/kg VPA or same volume of normal saline at the 10th and 12th days of gestation. The offspring exposed to VPA or saline during gestation were identified as autism spectrum disorder mice (VPA group) or normal control mice (CON group). Western blotting was used to detect the expression levels of PLCγ1, IP3R, CaMKⅡ and post-synaptic dense-95 (PSD95) in the hippocampus of the 2 groups. Golgi staining was employed to observe the changes in dendritic spines in the hippocampus of the offspring mice. Results Western blotting showed that the expression levels of PLCγ1, IP3R, CaMKⅡ and PSD95 were decreased in the VPA group than the normal control group (P < 0.01). Golgi staining indicated that compared with the normal control group, the density of dendritic spines in the hippocampus of VPA mice was reduced (P < 0.01). Conclusion In the hippocampus of VPA induced autism mice, the expression of PLCγ1/IP3R/CaMKⅡ and PSD95 and the dendritic spine density of pyramidal neurons in hippocampal CA1 are all decreased compared with the normal control mice.

A 100 million ton crude oil purchases and sale contract signed between China and Russia, and the crude oil will pass through Kazakhstan and flow along the Alashankou-Dushanzi-Urumchi crude oil pipeline to western Region. As an important crude oil import channel, this paper analyzes the current situation of Alashankou-Dushanzi-Urumchi crude oil pipeline and puts forward some countermeasures. Both Russia and Kazakhstan are major crude oil exporters, with internal demand for exporting crude oil to China. There is a huge gap between domestic crude oil demand, and social and economic development depends on crude oil import. The geographical environment of the crude oil pipeline is conducive to pipeline protection. The security environment of Xinjiang has improved. The situation in Russia and Ukraine and the civil strife in Kazakhstan have limited impact on the pipeline which will have good development opportunities. Thus, this paper proposes the following management strategies. First of all, strengthen communication and coordination between upstream and downstream enterprises. Second, reduce cost and increase efficiency. Third, attach importance of the application of new technologies. Fourth, establish emergency plans and hold emergency drills for emergencies such as COVID-19 outbreak and pipeline leakage. Fifth, strengthen anti-terrorism and riot control. Sixth, strengthen corporate culture and talent team construction.

Thermally comfortable mircoclimate is essential for creating high-quality outdoor spaces that attract citizens and boost city vitality. Previous design efforts to improve outdoor thermal comfort were usually conducted at large scales, such as city scale, neighborhood scale, urban block scale. Few researchers focused on the building scale. This study proposes an optimization framework based on genetic algorithm to determine the building shape, orientation, and location during early design stage that reduces the overall thermal stress in the target outdoor space. Solar radiation and wind fields were simulated to obtain the outdoor Universal Thermal Climate Index (UTCI) as the performance indicator. The simulations were validated against the experimental data. This investigation applied the proposed optimization framework to design the outdoor space for a kindergarten under the climate of Tianjin and Shanghai, respectively. The results showed that optimization reduced the overall thermal stress. The most favourable kindergarten forms were suggested through optimization. This study supplements the inverse design of outdoor thermal comfort at building scale and provides suggestions to create comfortable urban outdoor spaces.

The effect of adding sourdough with lactic acid bacteria (Lactobacillus plantarum M616) on dough quality and the sensory scores, specific volume, crumb firmness, and spread ratio of resultant Chinese steamed bread were studied. The moisture content of crumb and texture characteristics of the Chinese steamed bread with sourdough during storage were analyzed. In this study, 10%, 20%, 30%, and 40% of sourdough addition was investigated. The sourdough starter resulted in significant decrease in the water absorption, development time, stability, and farinograph quality number of the dough. The addition of sourdough improved the quality of Chinese steamed bread such as improving the sensory scores and specific volume, decreasing the crumb firmness, and a lower spread ratio was observed with an increase in the sourdough concentration up to 30%. Sourdough addition delayed a fast decrease in the moisture content of the Chinese steamed bread crumb during storage. The texture profile analysis of the bread crumb indicated that the addition of sourdough improved the quality and delayed the staling speed of Chinese steamed bread during storage. Moreover, inclusion of 30% sourdough produced the best protective effect on product staling.Supported by National Natural Science Foundation of China (31571780), Key Research Project in Higher Education of Henan (18A550002), Zhengzhou Science and Technology Innovation Team Program (121PCXTD518), School Funds of Henan University of Technology (2017QNJH11), and High-level Talent Foundation of Henan University of Technology (2017BS005) Keywords:: Sourdough, Chinese steamed bread, Dough quality, Shelf life, Texture profile analysis

Managing traffic flow in high-occupancy toll (HOT) lanes is a tough balancing act and current tolling schemes often lead to either under- or over-utilization of HOT lane capacity. The inherent linear/nonlinear relationship between flow and tolls in HOT lanes suggest that recent advances in machine learning and the use of a data-driven model may help set toll rates for optimal flow and lane use. In this research project, a data-driven model was developed, using long short-term memory (LSTM) neural networks to capture the underlying flow-toll pattern on both HOT and general-purpose lanes. Then, a dynamic control strategy, using linear quadratic regulator (LQR) feedback controller was implemented to fully utilize the HOT lane capacity while maintaining congestion-free conditions. A case study of the I-580 freeway in Alameda County, California was carried out. The control system was evaluated in terms of vehicle hours traveled and person hours traveled for solo drivers and carpoolers. Results show that the tolling strategy helps to mitigate congestion in HOT and general-purpose lanes, benefiting every traveler on I-580.

Optically active spin defects in wide bandgap semiconductors serve as a local sensor of multiple degrees of freedom in a variety of hard and soft condensed matter systems. Taking advantage of the recent progress on quantum sensing using van der Waals (vdW) quantum materials, here we report direct measurements of spin waves excited in magnetic insulator Y3Fe5O12 (YIG) by boron vacancy [Formula: see text] spin defects contained in few-layer-thick hexagonal boron nitride nanoflakes. We show that the ferromagnetic resonance and parametric spin excitations can be effectively detected by [Formula: see text] spin defects under various experimental conditions through optically detected magnetic resonance measurements. The off-resonant dipole interaction between YIG magnons and [Formula: see text] spin defects is mediated by multi-magnon scattering processes, which may find relevant applications in a range of emerging quantum sensing, computing, and metrology technologies. Our results also highlight the opportunities offered by quantum spin defects in layered two-dimensional vdW materials for investigating local spin dynamic behaviors in magnetic solid-state matters.