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While single-cell technologies have greatly advanced our comprehension of human brain cell types and functions, studies including large numbers of donors and multiple brain regions are needed to extend our understanding of brain cell heterogeneity. Integrating atlas-level single-cell data presents a chance to reveal rare cell types and cellular heterogeneity across brain regions. Here we present the Brain Cell Atlas, a comprehensive reference atlas of brain cells, by assembling single-cell data from 70 human and 103 mouse studies of the brain throughout major developmental stages across brain regions, covering over 26.3 million cells or nuclei from both healthy and diseased tissues. Using machine-learning based algorithms, the Brain Cell Atlas provides a consensus cell type annotation, and it showcases the identification of putative neural progenitor cells and a cell subpopulation of PCDH9highmicroglia in the human brain. We demonstrate the gene regulatory difference of PCDH9highmicroglia between hippocampus and prefrontal cortex and elucidate the cell–cell communication network. The Brain Cell Atlas presents an atlas-level integrative resource for comparing brain cells in different environments and conditions within the Human Cell Atlas.

The development of a strategy for imaging of glutathione (GSH) and apurinic/apyrimidinic endonuclease 1 (APE1) in an organism remains challenging despite their significance in elaborating the correlated pathophysiological processes. Therefore, in this study, we propose a DNA-based AND-gated nanosensor for fluorescence imaging of the GSH as well as APE1 in living cells, animals, and organoids. The DNA probe is composed of a G-strand and A-strand. The disulfide bond in the G-strand is cleaved through a GSH redox reaction, and the hybridization stability between the G-strand and A-strand is decreased, leading to a conformational change of the A-strand. In the presence of APE1, the apurinic/apyrimidinic (AP) site in the A-strand is digested, producing a fluorescence signal for the correlated imaging of GSH and APE1. This nanosensor enables monitoring of the expression level change of GSH and APE1 in cells. Additionally, we illustrate the capability of this “dual-keys-and-locked” conceptual methodology in achieving specific tumor imaging when GSH and APE1 are present simultaneously (overexpressed GSH and APE1 in tumor cells) with improving tumor-to-normal tissue ratio in vivo. Furthermore, using this nanosensor, the GSH and APE1 also are visualized in organoids that recapitulate the phenotypic and functional traits of the original biological specimens. Overall, this study demonstrates the potential of our proposed biosensing technology in investigating the roles of various biological molecules involved in specific diseases.

The low number of neural progenitor cells (NPCs) present in the adult and aged primate brains represents a challenge for generating high-yield and viable in vitro cultures of primary brain cells. Here we report a step-by-step approach for the fast and reproducible isolation of high-yield and viable primary brain cells, including mature neurons, immature cells and NPCs, from adult and aged macaques. We describe the anesthesia, transcardial perfusion and brain tissue preparation; the subsequent microdissection of the regions of interest and their enzymatic dissociation, leading to the separation of single cells. The cell isolation steps of our protocol can also be used for routine cell culturing, in particular for NPC expansion and differentiation, suitable for studies of hippocampal neurogenesis in the adult macaque brain. The purified primary brain cells are largely free from myelin debris and erythrocytes, paving the way for multiple downstream applications in vitro and in vivo. When combined with single-cell profiling techniques, this approach allows an unbiased and comprehensive mapping of cell states in the adult and aged macaque brain, which is needed to advance our understanding of human cognitive and neurological diseases. The neural cell isolation protocol requires 4 h and a team of four to six users with expertize in primary brain cell isolation to avoid tissue hypoxia during the time-sensitive steps of the procedure.

The extent to which neurogenesis occurs in adult primates remains controversial. In this study, using an optimized single-cell RNA sequencing pipeline, we profiled 207,785 cells from the adult macaque hippocampus and identified 34 cell populations comprising all major hippocampal cell types. Analysis of their gene expression, specification trajectories and gene regulatory networks revealed the presence of all key neurogenic precursor cell populations, including a heterogeneous pool of radial glia-like cells (RGLs), intermediate progenitor cells (IPCs) and neuroblasts. We identified HMGB2as a novel IPC marker. Comparison with mouse single-cell transcriptomic data revealed differences in neurogenic processes between species. We confirmed that neurogenesis is recapitulated in ex vivo neurosphere cultures from adult primates, further supporting the existence of neural precursor cells (NPCs) that are able to proliferate and differentiate. Our large-scale dataset provides a comprehensive adult neurogenesis atlas for primates.

Purpose: To evaluate the diagnostic accuracy of spectral-domain optical coherence tomography (SD-OCT) and swept-source optical coherence tomographic angiography (SS-OCTA) to identify polypoidal lesions in serous or serosanguinous maculopathy. Materials and methods: A retrospective review of patients presenting pigment epithelial detachments (PEDs) with the diagnosis of polypoidal choroidal vasculopathy (PCV), neovascular age-related macular degeneration (nAMD), and central serous chorioretinopathy (CSC), all of which underwent SD-OCT, SS-OCTA, and indocyanine green angiography (ICGA). Typical features of polypoidal lesions on SD-OCT included sharply peaked PED, notched PED, and hyperreflective ring underneath PED. SS-OCTA feature was vascularized PEDs on cross-sectional images corresponding to cluster-like structures on en face images. The parameters of PEDs were measured for analysis. Results: Of 72 eyes, 30 had PCV, 22 had nAMD, and 20 had CSC. A total of 128 localized PEDs were detected on SD-OCT. Typical features on SD-OCT had a high specificity (94.0%) but a limited sensitivity (73.8%). SS-OCTA features provided a higher sensitivity (96.7%). PEDs of the polypoidal lesions unrecognized by SD-OCT were dome-shaped, with smaller ratio of height to base diameter and less area, and almost had heterogeneous internal reflectivity and a connected double-layer sign. Some lesions misidentified by SS-OCTA developed into ICGA-proven polypoidal lesions at follow-up visits. Conclusion: A small dome-shaped PED with heterogeneous internal reflectivity and a connected double-layer sign on SD-OCT may suggest a polypoidal lesion of PCV. SS-OCTA may be a helpful tool to investigate preclinical PCV and observe the formation of polypoidal lesions.

Hydration mechanisms of hydratable alumina (HA) in citric acid at different pH are investigated in this study, aiming to improve rapid hydration process and massive hydration heat. By adding citric acid to adjust solution pHs to 2, 3, and 4, the crystal phase, morphologies, and microstructure of the HA hydrates are characterized by X-ray powder diffraction (XRD), differential scanning calorimetry (TG-DSC), and transmission electron microscopy (TEM), respectively. The results show that HA exhibits different hydration behaviors in different concentrations of acidic solutions. With decreasing pH of citric acid, the crystallinity of HA decreases whereas the dehydration process slows down. Excessive citric acid could displace hydroxyl which generates from pseudoboehmite gel. Meanwhile, the excess citrate ion can be absorbed on the surface of HA by forming numerous micelles, then compound to inhibit further hydration. Proper addition of citric acid helps to delay the hydration of HA and achieve better balance between bonding performance and hydration speed.

ABSTRACTWith spalling and corrosion during thermal cycles, the castable composites used in injecting lance are easily damaged. In order to solve this problem, we used carbon fibers as additives in the matrix, and prepared mullite- based castables with the addition of anti-oxidant silicon. It was found that the addition of carbon fibers could significantly improve the mechanical properties; the maximum mechanical strength was obtained when 0.1 wt% carbon fibers was added, and the maximum thermal shock resistance was obtained when 0.2 wt% carbon fibers was added. The carbon fibers were oxidized mostly after firing at 1100oC, while after firing at 1450oC, due to the dense oxide layers generated on the surface of the castables, most of the carbon fibers in the castables remained in good combination with the matrix. Some SiC whiskers with SiO2 coating were formed in the matrix after heat treatment at 1100oC in air. The model of the whiskers growth mechanism followed the vapour-solid mechanism.

Rhizoctonia cerealis, Bipolaris sorokiniana, and Fusariumspp. are three wheat-damaging soil-borne fungal pathogens causing sharp eyespot, common root rot, and crown rot, respectively. This study aimed to develop a multiplex PCR (mPCR) system to simultaneously detect these fungal pathogens. The mPCR assay was performed on wheat seedlings collected from a field in the Shandong Province. Specific primers were designed on the basis of the sequences of following genes: internal transcribed spacer (ITS) of R. cerealis, ITSof B. sorokiniana, and translation elongation factor (TEF1-α) of Fusariumspp., generating amplicons of 174, 418, and 600 bp, respectively. The mPCR system was optimized through an orthogonal design L18 (37) (three levels of five factors: three sets of primers, TaqDNA polymerase, and dNTPs) and statistical analysis. No nonspecific products were obtained upon amplification of nontarget species of the fungi. Sensitivity analysis revealed that the limit of detection of the mPCR assay for each pathogen was 100 pg. The mPCR results were further confirmed via subsequent visual diagnosis. The system developed herein provides a rapid, effective, and valuable method to simultaneously detect three soil-borne pathogens, thus facilitating prompt treatment and prevention of root diseases of wheat.

The enzyme C-14 sterol reductase is involved in biosynthesis of brassinosteroids (BR) and sterols, as well as plant development. OsFK1, a member of the sterol biosynthesis pathway located in the endoplasmic reticulum (ER), encodes C-14 sterol reductase. However, there is little research on the function of C-14 sterol reductase in rice. Compared with the wild type, an osfk1mutant showed dwarf phenotype and premature aging in the second leaf during the trefoil stage, and abnormal development of leaf veins during the tillering stage. The osfk1mutant showed signs of aberrant PCD, as evidenced by TUNEL staining. This suggested that high ROS buildup caused DNA damage and ROS-mediated cell death in the mutant. The osfk1mutant also showed decreased chlorophyll content and aberrant chloroplast structure. Sequencing of the osfk1mutant allele revealed a non-synonymous G to A mutation in the final intron, leading to early termination. Here, we identified the OsFK1allele, cloned it by Mutmap sequencing, and verified it by complementation. HPLC-MS/MS assays demonstrated that the osfk1mutation caused lower phytosterol levels. These findings showed that the OsFK1allele encoding C-14 sterol reductase is involved in phytosterol biosynthesis and mediates normal development of rice plants.

ABSTRACTIn this study, light-weight insulation materials were prepared with calcined flint clay as the main material and sawdust was infused by sols as a pore forming agent. Micro-porosity and properties of the prepared insulation materials were investigated and were found to have better comprehensive properties. Apparent porosity, bulk density and cold crushing strength of the compositions containing 40 wt% calcined flint clay, fired at 1400°C for 3 h, were found to be 71%, 0.85 g.cm–3and 2.65 MPa, respectively. Thermal conductivity of the material was 0.133 W.m–1.K –1at 300°C. When sawdust was soaked by 0 wt% sol, microstructure of the materials showed irregular pores. When sawdust was infused with 7 wt% alumina sol, the micropores were wrapped with larger pore. Meanwhile, the original pore was refined, and cold crushing strength and thermal conductivity were also optimized. When the sawdust was soaked in alumina sol, the cold crushing strength increased to 3.3 MPa and the thermal conductivity decreased to 0.116 W.m–1·K–1at 300°C. Grey correlation method indicated that the pore size of <2 µm, 2-6 µm and 18-26 µm had more significant influence on cold crushing strength and thermal conductivity.

A comprehensive search of PubMed and Embase was performed in January 2015 to examine the available literature on validated diagnostic models of the pre-test probability of stable coronary artery disease and to describe the characteristics of the models. Studies that were designed to develop and validate diagnostic models of pre-test probability for stable coronary artery disease were included. Data regarding baseline patient characteristics, procedural characteristics, modeling methods, metrics of model performance, risk of bias, and clinical usefulness were extracted. Ten studies involving the development of 12 models and two studies focusing on external validation were identified. Seven models were validated internally, and seven models were validated externally. Discrimination varied between studies that were validated internally (C statistic 0.66-0.81) and externally (0.49-0.87). Only one study presented reclassification indices. The majority of better performing models included sex, age, symptoms, diabetes, smoking, and hyperlipidemia as variables. Only two diagnostic models evaluated the effects on clinical decision making processes or patient outcomes. Most diagnostic models of the pre-test probability of stable coronary artery disease have had modest success, and very few present data regarding the effects of these models on clinical decision making processes or patient outcomes.

ABSTRACTIn this research, green porous mullite ceramics with high porosity, high strength and low thermal conductivity were fabricated by using insulator waste as the main raw material. The effects of sintering temperature on linear shrinkage rate (LSR), bulk density, apparent porosity, cold crushing strength (CCS), mean pore diameter and thermal conductivity of the porous mullite ceramics were investigated. As the sintering temperature increased from 1300oto 1500oC at intervals of 50oC, the LSR initially decreased from 1300oto 1400oC, and then increased from 1400oto 1500oC, while CCS and thermal conductivity increased constantly from 3.2 to 8.5 MPa and from 0.187 to W.m–1.K–1respectively. Meanwhile, the crystallization and morphology of the mullite grains were optimiz ed wit h t he incr easing sintering temperature. Comprehensive properties of specimens can be adjusted by changing the sintering temperature.

Ceramic ultrafine fibers (UFs) with flexibility and high strength have attracted considerable interest for use in extreme conditions. Herein, silicon carbide (SiC) UFs strengthening by gradient ZrO2nanocrystals (NCs) were prepared by electrospinning, vacuum-maturating, and pyrolysis. Gradient NCs structure formed during vacuum-maturation can be classified as surface dense ZrO2NCs, linear ZrO2nanoclusters, and core homogeneous ZrO2NCs. Notably, the obtained gradient ZrO2NCs/SiC (g-ZS) UF exhibits 2.6 times higher strength and 1.8 times higher strain than SiC UF, which results in a high toughness (41.32 MJ m−3). The design strategy and fabrication method of such high strength with functional gradient NCs structure holds great promise for highly reliable micro/nanodevices and other ceramic ultrafine fibers.

Retinal ganglion cells (RGCs) are the brain’s gateway to the visual world. They can be classified into different types on the basis of their electrophysiological, transcriptomic, or morphological characteristics. Here, we characterize the transcriptomic, morphological, and functional features of 472 high-quality RGCs using Patch sequencing (Patch-seq), providing functional and morphological annotation of many transcriptomic-defined cell types of a previously established RGC atlas. We show a convergence of different modalities in defining the RGC identity and reveal the degree of correspondence for well-characterized cell types across multimodal data. Moreover, we complement some RGC types with detailed morphological and functional properties. We also identify differentially expressed genes among ON, OFF, and ON-OFF RGCs such as Vat1l, Slitrk6, and Lmo7, providing candidate marker genes for functional studies. Our research suggests that the molecularly distinct clusters may also differ in their roles of encoding visual information.

Sialon-ZrN composites were synthesized from zircon and aluminium via an aluminothermic reduction and nitridation process. The effects of extra Al powder on the product phase compositions and morphologies were studied. Products with different phases and morphologies result from different surplus amounts of additional Al. With increases of Al, after firing at 1500°C, the amount of ZrSiO4decreased and the amount of sialon increased. The phase evolution of the specimens indicated that 8 mol-% extra Al powder contributed to the best decomposition of zircon and led to improved formation of sialon-ZrN composites.

Tau-fluvalinate (TFLV) is one of the most potent chiral synthetic pyrethroids to control a wide range of pests in agricultural fields, especially in apiary. In this study, two stereoisomers of TFLV were fully separated by high-performance liquid chromatography (HPLC) with a semipreparative chiral column using cellulose-tris(3,5-dimethylphenylcarbamate) as chiral stationary phase and n-hexane and 2-propanol (96/4, v/v) as mobile phase at a flow rate of 2.5 mL min−1. The (+)-stereoisomer was first eluted by detecting with an optical rotation detector. After obtaining pure single stereoisomer of TFLV, acute toxicities of each isomer and TFLV standard to zebrafish were evaluated. The results showed that the (+)-stereoisomer exhibited 273.4 times higher toxicity than the (−)-stereoisomer and 6.7 times higher than TFLV standard, according to their LC50 values at 96 h after exposure. This indicates that the toxicity of TFLV mainly originates from (+)-stereoisomer. These results are very helpful to prepare single stereoisomer of chiral pesticides and evaluate their different toxicological effects to aquatic organisms.