Synaptic pruning during adolescence is important for appropriate neurodevelopment and synaptic plasticity. Aberrant synaptic pruning may underlie a variety of brain disorders such as schizophrenia, ...autism and anxiety. Dopamine D2 receptor (Drd2) is associated with several neuropsychiatric diseases and is the target of some antipsychotic drugs. Here we generate self-reporting Drd2 heterozygous (SR-Drd2
) rats to simultaneously visualize Drd2-positive neurons and downregulate Drd2 expression. Time course studies on the developing anterior cingulate cortex (ACC) from control and SR-Drd2
rats reveal important roles of Drd2 in regulating synaptic pruning rather than synapse formation. Drd2 also regulates LTD, a form of synaptic plasticity which includes some similar cellular/biochemical processes as synaptic pruning. We further demonstrate that Drd2 regulates synaptic pruning via cell-autonomous mechanisms involving activation of mTOR signaling. Deficits of Drd2-mediated synaptic pruning in the ACC during adolescence lead to hyper-glutamatergic function and anxiety-like behaviors in adulthood. Taken together, our results demonstrate important roles of Drd2 in cortical synaptic pruning.
A new 2-D ultra-thin transmissive phase gradient metasurface (TPGM) with polarization-independent property is proposed based on the generalized Snell's law of refraction. The super unit cell of the ...tri-layer TPGM consists of 6 \times 6 suitably selected elements with - {60}^\circ phase gradient at x -direction and 60° phase gradient at y -direction, respectively. The characterizations and working mechanisms of the TPGM are investigated in depth through theoretical calculation, comparative analysis, and electromagnetic (EM) simulation. Four types of TPGMs with different functionalities are proposed based on the derived four-step design method. Numerical results show that the TPGMs are capable of manipulating the differently polarized wave independently. For demonstration and potential applications, an ultra-thin polarization beam splitter (PBS) working at X-band is implemented by a specially designed 2-D TPGM and is launched by a wideband horn antenna from the perspective of high integration, simple structure, and low cost. Numerical and experimental results coincide well, indicating that the PBS advances in many aspects such as separating and controlling the orthogonally polarized waves with a polarized splitting ratio better than 18 dB, obtaining a comparable bandwidth of more than 600 MHz, gaining a high transmission efficiency and also adopting a simple fabrication process based on the convenient print circuit board (PCB) technology.
Till now, the novel Mg alloys acting as the medical materials have drawn much attention, due to their spontaneous degradability, favorable mechanical properties and the excellent biocompatibilities. ...Unfortunately, they were inevitably affected by flow erosion, corrosion fatigue, stress-interaction and dynamic wear under the human body conditions, leading to significant mechanical-performance attenuation and premature fracture failure. Thus, how to explore and obtain the biomedical Mg-based alloys with controllable degradation rate and suitable biocompatibility was the key issue. Surface modification is a typical method to improve the corrosion resistance. It can isolate the Mg-matrix from the electrolyte by establishing the corrosion barrier without changing the microstructure characteristics. Also, it can change the layer structure and further enhance the degradation behaviors and biological activities of biomedical Mg alloys. In this text, the latest research progresses of surface modification for Mg alloys were reviewed, and the formation mechanism, film layer features as well as the rupture mechanism of conversion coatings were revealed. Besides, the interaction roles of Mg-matrix/modified-layer and modified-layer/electrolyte were analyzed through the comparison of film-layer structure, morphology and the establishment of degradation rates for various modified Mg alloys. Moreover, the internal relationships between the biological biocompatibilities and degradation rates in different corrosive conditions were deeply explored. Finally, the problems of surface modification on biomedical Mg alloys were proposed and the future development directions were prospected.
Our previous microarray data showed that microRNA‐224 (miR‐224) was downregulated in human prostate cancer (PCa) tissues compared with adjacent benign tissues. However, the underlying mechanisms by ...which miR‐224 is involved in PCa remain unclear. In this study, we identified TRIB1 as a target gene of miR‐224. Forced expression of miR‐224 suppressed PCa cell proliferation, invasion and migration, and promoted cell apoptosis by downregulating TRIB1. Moreover, the expression level of miR‐224 in PCa tissues was negatively correlated with that of TRIB1. miR‐224 downregulation was frequently found in PCa tissues with metastasis, higher PSA level and clinical stage, whereas TRIB1 upregulation was significantly associated with metastasis. Both miR‐224 downregulation and TRIB1 upregulation were significantly associated with poor biochemical recurrence‐free survival of patients with PCa. In conclusion, these findings reveal that the aberrant expression of miR‐224 and TRIB1 may promote PCa progression and have potentials to serve as novel biomarkers for PCa prognosis.
What's new?
Dysregulation of microRNA expression in cancer suggests that small, noncoding RNAs could be valuable biomarkers for disease detection and management. This study examined the role of miR‐224 expression in prostate cancer. The findings indicate that abnormal miR‐224 expression and its target TRIB1, a regulator of intracellular signalling, may be associated with aggressive progression and poor prognosis of prostate cancer. The tumor suppressive effects of miR‐224 in prostate cancer may be partially mediated by down‐regulating TRIB1 expression.
Due to excellent biological-functionality, unique/suitable elastic-modulus as well as spontaneous degradation behaviors, Mg alloys acted as medical implants have shown enormous potential in surgical ...operation and bone-fixation fields. Unfortunately, the extreme mass loss and unmarked-fracture could easily induce the implant failure. In the present study, the microstructure characteristics and degradation behaviors of the Mg-10.6Gd-0.3Ag-x(Y/Zn) alloys were investigated through the XRD, TEM, EPMA, XPS, 3D/CLSM and SECM. Results revealed that with the increment of Y/Zn contents, the amount of Mg24(Gd/Y)5 precipitates increased, which were mainly distributed in grains and on grain boundaries. The addition of Zn and Y increased the undercooling and Y had a large mismatch degree with Mg atoms, which could promote the precipitation of second phases. Additionally, the corrosion rates of Mg-10.6Gd-0.3Ag-x(Y/Zn) increased firstly and then reduced. Also, the best corrosion resistance was achieved in the Mg-10.6Gd-0.3Ag-Y-Zn, with the current intensities of 58.49 μA/cm2, attributed to the formation of continuous reticular structure oxide film, which can act as physical barriers and impede the corrosion process.
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•Corrosion rate of studied alloys were increased firstly and then reduced.•Y and Zn addition provide nucleation cites to form compact surface protective layer.•The evolution of corrosion current densities was analyzed by SECM.•Y and Zn addition promote the precipitation of Mg24(Gd, Y, Zn)5 phase.
Sample imbalance has always been an important issue to be solved in heavy precipitation forecasts. Introducing appropriate constraints into the loss function of a machine learning model can mitigate ...the negative impact of sample imbalance on model training. This study explores the role of Dice loss function in dealing with sample imbalance and verifies its application on the correction of heavy precipitation forecasts using the U-Net neural network. On this basis, the application of ordinal classification in forecasts correction is further verified. The results show that the concept of Dice loss is highly similar to that of threat score, which can suppress the negative impact of sample imbalance on heavy precipitation forecasts by ignoring most of the events that are insensitive to heavy precipitation forecasts. Model correction experiments further indicate that the correction models trained with weighted cross entropy, differentiable threat score loss and Dice loss (WCE, DTS and Dice models) improve the precipitation forecasts of ECMWF (European Centre for Medium-Range Weather Forecasts) model. For the forecasts of all precipitation levels, Dice model effectively suppresses false alarms while improving hits, whereas WCE model greatly promotes false alarms while significantly improving hits. In contrast, DTS model significantly suppresses large precipitation false alarms while improving its hits, but causes substantial small precipitation false alarms while significantly promoting its hits. As a result, for large precipitation forecasts, both Dice and DTS models perform significantly better than WCE model, while for small precipitation forecasts, Dice model performs better than DTS and WCE models. Furthermore, the correction model combining ordinal classification and Dice loss exhibits the best forecasting skill. This model further suppresses the false alarms of large precipitation while improving its hits.
•Dice loss can ignore most of the samples that are insensitive to the occurrence of heavy precipitation, thereby reducing sample imbalance.•The correction model with Dice loss significantly improves heavy precipitation forecasts by suppressing false alarms while promoting hits.•The combination of Dice loss with ordinal classification further suppresses false alarms and performs better in heavy precipitation forecasts.
► Phenolic compounds were compared between bagged and unbagged apple fruits. ► Fruit bagging lowered the phenolic compound concentrations in apple peels. ► Fruit bagging affected the phenolic ...compounds in apple flesh. ► The effects of bagging treatment differed among varieties.
Concentrations of eighteen types of phenolic compounds were compared between bagged and unbagged fruits in both the peel and the flesh of three apple cultivars, ‘Golden Delicious’, ‘Red Delicious’, and ‘Royal Gala’. Fruit bagging treatment significantly lowered the phenolic compound concentrations in apple peels, except the gallic acid and chlorogenic acid in ‘Red Delicious’. Among the detected phenolic compounds in fruit peels, anthocyanins were the most sensitive to fruit bagging, followed by flavonols. In apple flesh, chlorogenic acid, phloridzin, and flavanols were the major phenolic compounds. The concentration of chlorogenic acid in apple flesh was hardly affected by the bagging treatment. Fruit bagging did not affect the concentration of phloridzin in the flesh of ‘Golden Delicious’, but the treatment enhanced the content of the compound in ‘Red Delicious’ and reduced the concentration in ‘Royal Gala’. The flavanols concentration was reduced by the bagging treatment in the flesh of ‘Golden Delicious’ and ‘Red Delicious’, but remained unchanged in the flesh of ‘Royal Gala’. The concentration of total phenolics was higher in apple peel than in the flesh, except that chlorogenic acid was significantly higher in the flesh of either bagged or unbagged ‘Red Delicious’ and unbagged ‘Royal Gala’. Generally, fruit bagging treatment decreased most of the phenolic compound concentrations in both the peel and the flesh, especially those in peels. The effect of bagging treatment differed among cultivars.
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•Coupling plasma with Au/La0.5Ce0.5CoO3-δ boosts the oxidation removal of toluene.•Constructing Au sites on the La0.5Ce0.5CoO3-δ enables a strong synergism between the perovskites and ...plasma.•Au/La0.5Ce0.5CoO3-δ possesses large numbers of highly active Au-La0.5Ce0.5CoO3-δ and Au-CeO2 interfacial sites.•Au sites on the La0.5Ce0.5CoO3-δ make the plasma-catalytic system obtain a uniform discharge.
Plasma-catalysis technique is a promising approach to control air pollution caused by volatile organic compounds (VOCs). Perovskite-type oxides have excited much interest in constructing plasma-catalytic system for the oxidation removal of VOCs owing to their flexible electronic structure, alterable geometry, unique catalytic properties and high stability. However, the perovskites commonly suffer from low surface area and small amounts of active surface sites because of their high synthesis temperature, which limits the synergism between the perovskites and plasma and thus decreases the performance of plasma-catalytic oxidation of VOCs. Here we show that the oxidation removal of toluene (typical refractory VOCs) in the plasma-catalytic system is improved by constructing Au sites on a perovskite of La0.5Ce0.5CoO3-δ (Au/La0.5Ce0.5CoO3-δ). Compared with plasma-catalytic systems integrated by LaCoO3 or La0.5Ce0.5CoO3-δ, coupling the Au/La0.5Ce0.5CoO3-δ with plasma enables the boost of toluene conversion and CO2 selectivity, but suppresses the generation of secondary pollutants (O3 and NOx). The calculation of apparent activation energy (Ea) demonstrates that the plasma-catalytic system integrated by Au/La0.5Ce0.5CoO3-δ obtains lower Ea of 6.9 kJ/mol than those integrated by LaCoO3 (9.5 kJ/mol) and La0.5Ce0.5CoO3-δ (8.1 kJ/mol) as well as plasma alone (15.0 kJ/mol), confirming a favorable toluene oxidation process in the plasma coupling Au/La0.5Ce0.5CoO3-δ system. Catalyst characterizations, discharge diagnosis and density functional theory calculations suggest that depositing Au on the La0.5Ce0.5CoO3-δ render the favorable gas and surface reactions for toluene oxidation in the plasma-catalytic system and thus a strong synergism between the perovskites and plasma, by modulating the discharge mode and creating large numbers of highly active Auδ+-Oδ--Ce interfacial sites on the surface of La0.5Ce0.5CoO3-δ.
Using one year of Aerosol Optical Depth (AOD) derived from Moderate Resolution Imaging Spectroradiometer (MODIS) on the Terra satellite and particular matter (PM) contents measured at eleven sites ...located mostly in the eastern China in 2007, the relationship between columnar AOD and hourly and daily average (DA) PM were established. The peak AOD observed from MODIS was generally consistent with the surface PM measurements in eastern China, where Zhengzhou had the maximum annual mean PM
10 of 182.1 μg m
−3, while Longfengshan had the minimum annual mean of 38.1 μg m
−3. Ground level observations indicated that PM concentration varies widely across different regions, which was mainly due to the difference in weather conditions and anthropogenic emissions. The coarse particles accounted for the main air pollution in Zhengzhou and Benxi whiles the fine particles, however, were the main constituents in other sites. Results showed that MODIS AOD (averaged over the box of 5 × 5 and 3 × 3 pixels) had a better positive correlation with the coincident hourly average (HA) PM concentration than with DA due to diurnal variation in PM mass measurements. After correcting AOD for relative humidity (RH), the correlation did not improve significantly, suggesting that the RH was not the main factor affecting the correlation of PM with AOD. The statistical regression analysis between MODIS AOD and PM mass suggested that the satellite-derived AOD is a useful tool for mapping PM distribution over large spatial domains.
While large-scale rock strata affected by underground coal mining have been widely studied through numerical modeling, there are still some aspects that can be better understood. Specifically, ...researchers do not fully utilize borehole logs and test results of rock specimens to reveal rock mass property variation along horizontal directions and strata lateral thickness variation at bed level. In this paper, we address this knowledge gap by proposing a data-intensive numerical modeling method (DINMM) that can make full use of these data with consideration of the modeling limitations of BlockRanger, a grid generation tool. Both the proposed method and the conventional numerical modeling method (CNMM) are applied to the Ying-Pan-Hao coal mine via the FLAC3D (Fast Lagrangian Analysis of a Continua in 3 Dimensions) package, and their predictions are then calibrated and compared to discuss the validity. Results show that, compared to the CNMM-based predictions, the root mean square error of 70 monitoring points is decreased at least by 27.4% in the DINMM-based prediction, and the relative error of maximum subsidence is reduced by 5.1% with a reduction rate of 66.5% on average, even though the CNMM-based model was originally better calibrated. We also find that a DINMM-based model is more in line with field observations and theoretical understanding in terms of displacement, stress, and failure propagation. The notion of data-intensive modeling seems to be quite promising and the DINMM should be useful for a better understanding of strata movement and subsidence prediction.
Highlights
• We propose a data-intensive modeling method (DINMM) to build numerical models based on multiple borehole logs, rather than on a single or generalized borehole log.
• We realized rock mass property variation along horizontal directions and strata lateral thickness variation at bed level when modeling large-scale rock strata.
• We find that the root mean square error of 70 monitoring points is decreased at least by 27.4% in the DINMM-based prediction, even though the control model was originally better calibrated.
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