The recent advancement in spatial transcriptomics technology has enabled multiplexed profiling of cellular transcriptomes and spatial locations. As the capacity and efficiency of the experimental ...technologies continue to improve, there is an emerging need for the development of analytical approaches. Furthermore, with the continuous evolution of sequencing protocols, the underlying assumptions of current analytical methods need to be re-evaluated and adjusted to harness the increasing data complexity. To motivate and aid future model development, we herein review the recent development of statistical and machine learning methods in spatial transcriptomics, summarize useful resources, and highlight the challenges and opportunities ahead.
With the development of the modern sports concept, physical education mode in colleges and universities needs to adapt to the requirements of the new era. In this paper, we studied the feasibility ...and comparative advantages of exercise prescription physical education, collected physical fitness test data of college students, completed the cluster analysis of student physical test data based on the k-medoids algorithm, used semi-supervised RBF neural network to learn each cluster, and generated an exercise prescription for each class of students. In the comparative teaching, the performance of students in the experimental class improved in standing long jump and 50 m, and the changes were statistically significant with p-values less than 0.05. While the indicators in the control class improved slightly before and after the experiment, the p-values were greater than 0.05, and there was no significant difference.
Hydrogen peroxide (H
O
) synthesis by electrochemical oxygen reduction reaction has attracted great attention as a green substitute for anthraquinone process. However, low oxygen utilization ...efficiency (<1%) and high energy consumption remain obstacles. Herein we propose a superhydrophobic natural air diffusion electrode (NADE) to greatly improve the oxygen diffusion coefficient at the cathode about 5.7 times as compared to the normal gas diffusion electrode (GDE) system. NADE allows the oxygen to be naturally diffused to the reaction interface, eliminating the need to pump oxygen/air to overcome the resistance of the gas diffusion layer, resulting in fast H
O
production (101.67 mg h
cm
) with a high oxygen utilization efficiency (44.5%-64.9%). Long-term operation stability of NADE and its high current efficiency under high current density indicate great potential to replace normal GDE for H
O
electrosynthesis and environmental remediation on an industrial scale.
Graphene-based materials are being hotly pursued for energy and environment applications. Inspired by the recent experimental synthesis of Fe2 dimer supported on graphene (He, Z.; He, K.; Robertson, ...A. W.; Kirkland, A. I.; Kim, D.; Ihm, J.; Yoon, E.; Lee, G.-D.; Warner, J. H. Nano Lett. 2014, 14, 3766–3772), here using large-scale screening-based density functional theory and microkinetics modeling, we have identified that some transition metal dimers (Cu2, CuMn, and CuNi), when supported on graphene with adjacent single vacancies (labeled as XY@2SV), perform better in CO2 electroreduction with reduced overpotental and enhanced current density. Specifically, Cu2@2SV is catalytically active toward CO production, similar to Au electrodes but distinct from bulk Cu; MnCu@2SV is selective toward CH4 generation, while NiCu@2SV promotes CH3OH production because of the difference in oxophilicity between incorporated Mn and Ni. The advantages of the outstanding selectivity of products, the high dispersity of spatial distribution, and the reduced overpotentials allow these new systems to be promising catalysts, which will motivate more experimental research in this direction to further explore graphene-based materials for CO2 conversion.
In the present work, carbon black (CB) works as a pore-forming agent in the preparation of alumina porous ceramics. The pore structures (i.e. mean pore size, pore size distribution and various pores ...size proportions) were characterized by means of Micro-image Analysis and Process System (MIAPS) software and mercury intrusion porosimetry. Then their correlation and thermal conductivity as well as strength were determined using grey relation theory. The results showed that the porosity and mean pore size increased against the amount of CB, whereas the thermal conductivity, cold crushing strength and cold modulus of rupture reduced. The <2μm pores were helpful for enhancing the strength and decreasing the thermal conductivity whereas the >14μm pores had the opposite effects.
The purpose of the present cross-sectional study was to clarify the effects of sport expertise and shot results on the action anticipation of basketball players. Eighty-eight male subjects ...participated in this study, namely, 30 collegiate basketball players, 28 recreational basketball players and 30 non-athletes. Each participant performed a shot anticipation task in which he watched the shooting phase, rising phase, high point and falling phase of a free throw and predicted the fate of the ball. The results showed that the collegiate players and recreational players demonstrated higher accuracy than the non-athletes for the falling phase but not for the other temporal conditions. Analysis of the shot results demonstrated that for made shots, the collegiate players and recreational players provided more accurate predictions than the non-athletes. These results suggested that the experienced players required a sufficient amount of information to be able to make accurate judgements and demonstrated that the experts' judgement bias for made shots was independent of the temporal condition.
Though whole exome sequencing (WES) is the gold-standard for measuring tumor mutational burden (TMB), the development of gene-targeted panels enables cost-effective TMB estimation. With the growing ...number of panels in clinical trials, developing a statistical method to effectively evaluate and compare the performance of different panels is necessary. The mainstream method uses R-squared value to measure the correlation between the panel-based TMB and WES-based TMB. However, the performance of a panel is usually overestimated via R-squared value based on the long-tailed TMB distribution of the dataset. Herein, we propose angular distance, a measurement used to compute the extent of the estimated bias. Our extensive in silico analysis indicates that the R-squared value reaches a plateau after the panel size reaches 0.5 Mb, which does not adequately characterize the performance of the panels. In contrast, the angular distance is still sensitive to the changes in panel sizes when the panel size reaches 6 Mb. In particular, R-squared values between the hypermutation-included dataset and the non-hypermutation dataset differ widely across many cancer types, whereas the angular distances are highly consistent. Therefore, the angular distance is more objective and logical than R-squared value for evaluating the accuracy of TMB estimation for gene-targeted panels.
Quartz is one of the most common rock-forming minerals and crystallizes over a wide range of temperature and pressure conditions. This diversity of quartz crystallization environments is reflected by ...trace-element compositional variations, which can be used to distinguish between different source sediments. Trace elements that are incorporated into the quartz lattice form corresponding paramagnetic centers (impurity centers, such as Al and Ti centers), which can be detected using the electron spin resonance (ESR) method. However, whether the quartz impurity center ESR signal intensity (quartz ESR-SI) can be used for quartz sediment provenance tracing remains uncertain. In the present study, five present-day (modern) fluvial sediments from the Songhua, Yellow, Yangtze, Huai, and Pearl rivers in China and eight ancient fluvial sand lenses from the Yichang Gravel Layer (YGL) located in the middle Yangtze River were sampled for major- and trace-element determinations by ICP-OES and ICP-MS for the purpose of provenance discrimination. A total of 1404 ESR spectra were also collected to evaluate the effect of γ-ray dose (varying from 50 to 50 000 Gy) on quartz ESR-SI to establish the relationship between quartz element contents and quartz ESR-SIs and thereby to assess the potential utility of quartz ESR-SI for sediment provenance analysis. Results indicate that: (1) quartz collected from the different studied locations can be distinguished by element contents; (2) the quartz Al center ESR-SI increases with increasing γ-ray dose from 50 to 50 000 Gy; (3) the quartz Ti center ESR-SI increases within a γ-ray dose of 10 000 Gy and decreases beyond 10 000 Gy; (4) quartz Al and Ti center ESR-SIs are closely related to the contents of Al and Ti in quartz; and (5) a plot of quartz Ti center ESR-SI vs. Al center ESR-SI using data for a γ-ray dose range of 4000-7000 Gy is the best indicator of fluvial sediment provenance using the ESR method.
Perfluorosulfonic acid (PFSA)-based ionomers, most notably Nafion, provide the ionic connection between catalyst particles and solid polymer ion conducting membrane separators in polymer electrolyte ...membrane fuel cells (PEMFCs). While necessary, their presence adversely impacts the performance of the catalyst. PEMFC catalyst performance losses associated with Nafion ionomers are due to physical barriers to reactant gas transport and loss of active sites through specific adsorption of polymer-bound sulfonate groups on the catalyst surface. These impacts are particularly damaging for PEMFC high current density (HCD) performance. Here, we show that ionic liquids (IL) present at the catalyst interface can act to prevent the specific adsorption of sulfonate groups of Nafion on Pt surfaces, negating the detrimental impact of the ionomer on reaction rates, specifically for the oxygen reduction reaction (ORR). This result holds promise for further Pt loading reductions in PEMFCs.
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•The functionalized layered double hydroxide (LDH) was fabricated following the double modification.•The functionalized LDH improved the fire safety and mechanical properties of epoxy ...resin simultaneously.•Incorporation of the functionalized LDH provided a stable and compact char layer.•The interfacial combination between LDH coated Mg2B2O5 whisker and epoxy resin was enhanced by dodecyl dihydrogen phosphate grafting.
A composite particle with layered double hydroxide (LDH) was deposited onto the surface of the Mg2B2O5 whisker (MBW) using a co-precipitation method. Subsequently, dodecyl dihydrogen phosphate (DDP) was grafted onto the surface of the LDH-coated MBW to synthesize an inorganic–organic hybrid (MBW@LDH–DDP). The MBW@LDH–DDP was incorporated into epoxy resin (EP) to fabricate a composite, and its curing behavior, fire properties, and mechanical properties were assessed. The results revealed that the cure index value of the EP/MBW@LDH–DDP composite was between ΔT* and ΔH*, indicating an excellent cured state. Moreover, it exhibited good flame-retarding performance (LOI: 32.5%; UL94: V-1 rating; flame retardancy index: 1.57). The improved fire safety was attributed to the barrier function of MBW, the presence of metallic oxides generated from LDH, and the catalytic dehydration of phosphorus oxoacids produced during the decomposition of DDP. The PO radicals generated from DDP were capable of capturing HO and H radicals in the gaseous phase. Furthermore, the incorporation of MBW@LDH–DDP improved the mechanical properties of the EP. The results presented herein can be applied to developing a novel strategy for designing multifunctional flame retardants that can be used to decrease the fire risk of EP.
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