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ARID1A, an SWI/SNF chromatin-remodeling gene, is commonly mutated in cancer and hypothesized to be a tumor suppressor. Recently, loss-of-function of ARID1A gene has been shown to cause intellectual disability. Here we generate Arid1a conditional knockout mice and investigate Arid1a function in the hippocampus. Disruption of Arid1a in mouse forebrain significantly decreases neural stem/progenitor cells (NSPCs) proliferation and differentiation to neurons within the dentate gyrus (DG), increases perinatal and postnatal apoptosis, leading to reduced hippocampus size. Moreover, we perform single-cell RNA sequencing (scRNA-seq) to investigate cellular heterogeneity and reveal that Arid1a is necessary for the maintenance of the DG progenitor pool and survival of post-mitotic neurons. Transcriptome and ChIP-seq analysis data demonstrate that ARID1A specifically regulates Prox1 by altering the levels of histone modifications. Overexpression of downstream target Prox1 can rescue proliferation and differentiation defects of NSPCs caused by Arid1a deletion. Overall, our results demonstrate a critical role for Arid1a in the development of the hippocampus and may also provide insight into the genetic basis of intellectual disabilities such as Coffin–Siris syndrome, which is caused by germ-line mutations or microduplication of Arid1a.

The spontaneous combustion of underground minerals causes huge property losses and ecological damage. Coal and oil shale are co-associated minerals in the Fushun West Mine, and both have the ability to undergo oxidative spontaneous combustion. To study the effect of microstructure changes on the macroscopic gas product concentration during the mineral oxidation spontaneous combustion process in the Fushun West Mine, this study used a high-temperature temperature-programmed test to obtain the change trend of gas product concentration in different oxidation stages of minerals. Using Fourier transform infrared spectroscopy technology, the changes in active functional groups of surface molecules during the process of mineral oxidation and spontaneous combustion were identified. Finally, using the gray correlation degree, correlation analysis between the concentration of gas products and the concentration of active functional groups in different oxidation stages was carried out. The key reactive functional groups affecting mineral spontaneous combustion were identified. The essential reason for the change in the gas product was revealed.

In this paper, by using an extension of Mawhin’s continuation theorem and some analysis methods, we study the existence of periodic solutions for the following prescribed mean curvature system $$\frac{d}{{dt}}\varphi \left( {x'} \right) + \nabla W\left( x \right) = p\left( t \right),$$ where x ∊ ℝn, W ∊ C1(ℝn, ℝ), p ∊ C(ℝ, ℝn) is T-periodic and $$\varphi \left( x \right)\frac{x}{{\sqrt {1 + |x{|^2}} }}.$$

Coal spontaneous combustion (CSC) has a devastating effect on the environment and human health. CSC primarily involves oxygen-lean oxidation and combustion states. In this study, to investigate the evolution of the coal microstructure during CSC in an oxygen-lean atmosphere, coal for oxygen-lean combustion was obtained and combusted at characteristic temperatures by using an independently developed electric tube furnace. Through Fourier-transform infrared spectroscopy, the relative contents of the active functional group of the initial-state oxidation coal were explored, and the main active functional groups, namely aromatic hydrocarbon, the oxygen functional group, aliphatic hydrocarbon, and the hydroxyl group, with the characteristic temperature, were determined. The sensitivities of different active functional groups to oxygen concentrations were analysed. In practice, a 10 vol% oxygen concentration was the key factor, inhibiting and promoting various active functional groups and exhibiting distinct dominance at various stages. Finally, the oxygen concentrations affected the gas concentration release characteristics, thereby determining the correlation degree of the key group and the oxygen concentration, as well as verifying the oxygen concentration sensitivity of the microstructure. The groups highly correlated with CSC characteristic parameters were mainly –CH2 and –CH3. The research results suggested remarkable explanatory potential to further elucidate the evolution of microstructures in oxygen-lean CSC.

In this paper, the authors consider the problem of existence of periodic solutions for a second order neutral functional differential system with nonlinear difference D-operator. For such a system, since the possible periodic solutions may not be differentiable, our method is based on topological degree theory of condensing field, not based on Leray Schauder topological degree theory associated to completely continuous field.

By means of Mawhin’s continuation theorem and some analysis methods, the existence of 2kT-periodic solutions is studied for a class of neutral functional differential equations, and then a homoclinic solution is obtained as a limit of a certain subsequence of the above periodic solutions set.

The main aim of this paper is to use the continuation theorem of coincidence degree theory for studying the existence of periodic solutions to a kind of neutral functional differential equation as follows: $$ {\left( {x{\left( t \right)} - {\sum\limits_{i = 1}^n {c_{i} x{\left( {t - r_{i} } \right)}} }} \right)}^{{\prime \prime }} = f{\left( {x{\left( t \right)}} \right)}{x}\ifmmode{'}\else$'$\fi{\left( t \right)} + g{\left( {x{\left( {t - \tau } \right)}} \right)} + p{\left( t \right)}. $$ In order to do so, we analyze the structure of the linear difference operator A : C 2π →C 2π, \( {\left[ {Ax} \right]}{\left( t \right)} = x{\left( t \right)} - {\sum\nolimits_{i = 1}^n {c_{i} x{\left( {t - r_{i} } \right)}} } \) to determine some fundamental properties first, which we are going to use throughout this paper. Meanwhile, we also prove some new inequalities which are useful for estimating a priori bounds of periodic solutions.

In this paper, the authors consider the existence of periodic solutions for a kind of second neutral functional differential equation as follows: $$ {\left( {x{\left( t \right)} - cx{\left( {t - \tau } \right)}} \right)}^{{\prime \prime }} = g{\left( {t,x{\left( {t - \mu {\left( t \right)}} \right)}} \right)} + e{\left( t \right)}, $$ in the critical case |c| = 1. By employing Mawhin's continuation theorem and some analysis techniques, some new results are obtained.

By means of the continuation theorem of coincidence degree theory, some new results on the non–existence, existence and unique existence of periodic solutions for a kind of second order neutral functional differential equation are obtained.

Continuously tunable second harmonic generation of 294. 8-280. 5 nm was obtained by Q -switched Nd:YAG laser pumped Rh. 6G dye laser in a 45t cutting fl -BaB2O4(BBO) crystal. The output energy of the second harmonic wave is about 8mJ around 285 nm. The continuously tunable output over the range of 230. 8-223. 2 nm was also obtained by the sum frequency mixing between the residual pump fundamental wave (1064 nm) and the second harmonic wave of Rh. 6G dye laser in other 45 cutting BBO crystal. The sum frequency output energy is about 120 A‚µ J around 227nm, the corresponding peak power is 12 kW. The key techniques of sum frequency generation were indicated.