This paper uses CFD software ANSYS Fluent, based on RSM Reynolds stress model and VOF two-phase flow model, to calculate the turbulent flow field inside the ∅75mm heavy dispersed phase particle ...separation cyclone. Combined with the experimental working parameters under different inlet pressures, the experimental results were compared. Check the accuracy of the formula calculation results and the numerical simulation results. The results show that the air column inside the cyclone is stable and the internal pressure gradient is continuous Well, the numerical simulation results of the axial and tangential velocity fields are consistent with the reality. Compared with the empirical formula, fluent numerical simulation software can more accurately predict the processing capacity of hydrocyclone, and the classification efficiency obtained is close to the experimental value.
Copper oxide nanoparticles (CuO NPs) are widely used as catalysts or semiconductors in material fields. Recent studies have suggested that CuO NPs have adverse genotoxicity and cytotoxicity effects ...on various cells. However, little is known about the toxicity of CuO NPs following exposure to murine lungs. The purpose of this fundamental research was to investigate whether CuO NPs could induce epithelial cell injury, pulmonary inflammation, and eventually fibrosis in C57BL/6 mice. Our studies showed that CuO NPs aggravated pulmonary inflammation in a dose-dependent manner. CuO NPs induced apoptosis of epithelial cells as indicated by TUNEL staining, flow cytometry and western blot analysis, which was partially caused by increased reactive oxygen species (ROS). In addition, CuO NPs exposure promoted collagen accumulation and expression of the progressive fibrosis marker α-SMA in the lung tissues, indicating that CuO NP inhalation could induce pulmonary fibrosis in C57BL/6 mice. All data provide novel evidence that there is an urgent need to prevent the adverse effects of CuO NPs in the human respiratory system.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The outbreak of COVID-19 in 2020 has had drastic impacts on urban economies and activities, with transit systems around the world witnessing an unprecedented decline in ridership. This paper attempts ...to estimate the effect of COVID-19 on the daily ridership of urban rail transit (URT) using the Synthetic Control Method (SCM). Six variables are selected as the predictors, among which four variables unaffected by the pandemic are employed. A total of 22 cities from Asia, Europe, and the US with varying timelines of the pandemic outbreak are selected in this study. The effect of COVID-19 on the URT ridership in 11 cities in Asia is investigated using the difference between their observed ridership reduction and the potential ridership generated by the other 11 cities. Additionally, the effect of the system closure in Wuhan on ridership recovery is analyzed. A series of placebo tests are rolled out to confirm the significance of these analyses. Two traditional methods (causal impact analysis and straightforward analysis) are employed to illustrate the usefulness of the SCM. Most Chinese cities experienced about a 90% reduction in ridership with some variation among different cities. Seoul and Singapore experienced a minor decrease compared to Chinese cities. The results suggest that URT ridership reductions are associated with the severity and duration of restrictions and lockdowns. Full system closure can have severe impacts on the speed of ridership recovery following resumption of service, as demonstrated in the case of Wuhan with about 22% slower recovery. The results of this study can provide support for policymakers to monitor the URT ridership during the recovery period and understand the likely effects of system closure if considered in future emergency events.
•The Synthetic Control Method helps evaluate COVID-19's impact on public transit.•A reduction effect of COVID-19 on ridership is indicated in most Chinese cities.•Ridership reduction varies between cities and is not guided by the infection rate.•Ridership reduction is influenced by the severity and duration of lockdowns.•Full system closure delayed the ridership recovery following service resumption.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Aluminum oxynitride (AlON) ceramics doped with different sintering aids were synthesized by spark plasma sintering process. The microstructures, mechanical, and optical properties of the ceramics ...were investigated. The results indicate that the optimal amount of sintering aids is 0.06 wt% La2O3 + 0.16 wt% Y2O3 + 0.30 wt% MgO. The addition of La3+ and Mg2+ decreases the rate of grain boundary migration in ceramics, promotes pore elimination, and inhibits grain growth. The addition of Y3+ facilitates liquid‐phase sintering of AlON ceramics. Moreover, the addition of Mg2+ effectively promotes twin formation in the ceramics, which hinders crack propagation and dislocation motion when the ceramics are loaded. Hence, the AlON ceramic doped with 0.06 wt% La2O3 + 0.16 wt% Y2O3 + 0.30 wt% MgO exhibits a relative density of 99.95%, an average grain size of 9.42 μm, and a twin boundary content of 10.3%, which contributes to its excellent mechanical and optical properties.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Due to the intriguing chemical variability and structure–property flexibility, molecular materials with striking multifunctional characteristics, including tunable physical, chemical, optical, and ...electronic properties, have aroused wide attention. Recently, great advances have also been made in designing molecular ferroelastics with optoelectronic properties. However, the band gaps of the most typical ferroelastics are far in excess of 2.0 eV, which severely hinder their further applications. And this corresponds to the inherent incompatibility of ferroelastics. Herein we report an organometallic compound, ferrocenium tetrachloroferrate (1), undergoing a ferroelastic phase transition at 407.7 K with a large spontaneous strain of 0.1088. To the best of our knowledge, this is the first molecular ferroelastic with such a high Curie temperature (T c) and narrow band gap of 1.61 eV. UV–vis absorption spectra and density-functional theory (DFT) calculation confirm this band gap. The band gap of 1 is determined by both the ferrocenium and the tetrachloroferrate components. The ideal semiconducting characteristic makes a breakthrough in the inherent incompatibility with ferroelastics. This will inspire an intriguing and further research in molecular ferroelastics with ideal semiconductor characteristics and hold great potential for the utilization in optoelectronic devices, especially the photovoltaic applications.
Full text
Available for:
IJS, KILJ, NUK, PNG, UL, UM
Target detection is one of the research hotspots in remote sensing image information extraction, which has a wide range of application prospects. Compared with natural images, remote sensing images ...are characterized by many dense small targets, large changes in target scale, and fuzzy target appearance under complex backgrounds. Therefore, this paper proposes the YOLO-FSD remote sensing image target detection algorithm. Firstly, to address the problem of fuzzy target appearance under complex background, a Swin-CSP structure is introduced in each layer of the network, which enhances the model's discriminative ability by learning the target's local and global attributes. Then, the Faster-SPPCSPC module is designed to efficiently solve the problem of large target scale variation by improving the feature pyramid. Finally, a new DWC-Head is utilized to reduce the prediction bias due to tiny and dense targets and to improve the model's localization and classification ability in complex backgrounds. Our extensive experiments show that our proposed YOLO-FSD algorithm improves AP and mAP by 3.9% and 3.3%, respectively, on the VisDrone dataset compared to the original YOLOv7 algorithm. The AP and mAP are improved by 3.6% and 4.2% on the DOTA dataset, and the inference speed reaches 15.3ms, which has better detection accuracy and inference speed.
Summary
Accurate and high‐throughput phenotyping of the dynamic response of a large rice population to drought stress in the field is a bottleneck for genetic dissection and breeding of drought ...resistance.
Here, high‐efficiency and high‐frequent image acquisition by an unmanned aerial vehicle (UAV) was utilized to quantify the dynamic drought response of a rice population under field conditions. Deep convolutional neural networks (DCNNs) and canopy height models were applied to extract highly correlated phenotypic traits including UAV‐based leaf‐rolling score (LRS_uav), plant water content (PWC_uav) and a new composite trait, drought resistance index by UAV (DRI_uav).
The DCNNs achieved high accuracy (correlation coefficient R = 0.84 for modeling set and R = 0.86 for test set) to replace manual leaf‐rolling rating. PWC_uav values were precisely estimated (correlation coefficient R = 0.88) and DRI_uav was modeled to monitor the drought resistance of rice accessions dynamically and comprehensively. A total of 111 significantly associated loci were detected by genome‐wide association study for the three dynamic traits, and 30.6% of them were not detected in previous mapping studies using nondynamic drought response traits.
Unmanned aerial vehicle and deep learning are confirmed effective phenotyping techniques for more complete genetic dissection of rice dynamic responses to drought and exploration of valuable alleles for drought resistance improvement.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Mesenchymal stem cells (MSCs) are typically defined by their in vitro characteristics, and as a consequence the in vivo identity of MSCs and their niches are poorly understood. To address this issue, ...we used lineage tracing in a mouse incisor model and identified the neurovascular bundle (NVB) as an MSC niche. We found that NVB sensory nerves secrete Shh protein, which activates Gli1 expression in periarterial cells that contribute to all mesenchymal derivatives. These periarterial cells do not express classical MSC markers used to define MSCs in vitro. In contrast, NG2+ pericytes represent an MSC subpopulation derived from Gli1+ cells; they express classical MSC markers and contribute little to homeostasis but are actively involved in injury repair. Likewise, incisor Gli1+ cells, but not NG2+ cells, exhibit typical MSC characteristics in vitro. Collectively, we demonstrate that MSCs originate from periarterial cells and are regulated by Shh secretion from an NVB.
Display omitted
•The neurovascular bundle represents an in vivo niche for MSCs•Sensory nerves secrete Shh to regulate MSCs surrounding the arterioles•Classical MSC markers define pericytes, which represent an MSC subpopulation in vivo•Pericytes contribute mainly to injury repair, but not homeostasis
Zhao et al. identify a Shh-secreting neurovascular bundle as an in vivo niche for MSCs. Pericytes are an MSC subpopulation that contributes to injury repair, but not homeostasis.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Rice (Oryza sativa) is an important dietary source of both essential micronutrients and toxic trace elements for humans. The genetic basis underlying the variations in the mineral composition, the ...ionome, in rice remains largely unknown. Here, we describe a comprehensive study of the genetic architecture of the variation in the rice ionome performed using genome-wide association studies (GWAS) of the concentrations of 17 mineral elements in rice grain from a diverse panel of 529 accessions, each genotyped at ∼6.4 million single nucleotide polymorphism loci. We identified 72 loci associated with natural ionomic variations, 32 that are common across locations and 40 that are common within a single location. We identified candidate genes for 42 loci and provide evidence for the causal nature of three genes, the sodium transporter gene Os-HKT1;5 for sodium, Os-MOLYBDATE TRANSPORTER1;1 for molybdenum, and Grain number, plant height, and heading date7 for nitrogen. Comparison of GWAS data from rice versus Arabidopsis (Arabidopsis thaliana) also identified well-known as well as new candidates with potential for further characterization. Our study provides crucial insights into the genetic basis of ionomic variations in rice and serves as an important foundation for further studies on the genetic and molecular mechanisms controlling the rice ionome.
•Astrocytic Kir6.1 knockout aggravates dopaminergic neurons degeneration.•Astrocytic Kir6.1 knockout inhibits mitophagy in astrocytes.•Astrocytic Kir6.1 knockout enhances NLRP3 inflammasome-mediated ...neuroinflammation.•Restoration of mitophagy rescues the deleterious effect of astrocytic Kir6.1 deletion.
ATP-sensitive potassium (K-ATP) channels, coupling cell metabolism to cell membrane potential, are involved in brain diseases, including Parkinson’s disease (PD). Kir6.1, a pore-forming subunit of K-ATP channel, is prominently expressed in astrocytes and participates in regulating its function. However, the precise role of astrocytic Kir6.1-contaning K-ATP channel (Kir6.1/K-ATP) in PD is not well characterized. In this study, astrocytic Kir6.1 knockout (KO) mice were used to examine the effect of astrocytic Kir6.1/K-ATP channel on dopaminergic (DA) neurodegeneration triggered by the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. Here, we found that astrocytic Kir6.1 KO mice showed more DA neuron loss in substantia nigra compacta (SNc), lower level of dopamine in the striatum, and more severe motor dysfunction than controls. Interestingly, this companied by increased neuroinflammation and decreased autophagy level in SNc in vivo and astrocytes in vitro. Mechanistically, astrocytic Kir6.1 KO inhibited mitophagy which resulted in an increase in the accumulation of damaged mitochondria, production of reactive oxygen species and neuroinflammation in astrocytes. Restoration of astrocytic mitophagy rescued the deleterious effects of astrocytic Kir6.1 ablation on mitochondrial dysfunction, inflammation and DA neuron death. Collectively, our findings reveal that astrocytic Kir6.1/K-ATP channel protects against DA neurodegeneration in PD via promoting mitophagy and suggest that astrocytic Kir6.1/K-ATP channel may be a promising therapeutic target for PD.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
PDF
