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Monitoring forest species diversity is essential for biodiversity conservation and ecological management. Currently, unmanned aerial vehicle (UAV) remote sensing technology has been increasingly used in biodiversity monitoring due to its flexibility and low cost. In this study, we compared two methods for estimating forest species diversity indices, namely the spectral angle mapper (SAM) classification approach based on the established species-spectral library, and the self-adaptive Fuzzy C-Means (FCM) clustering algorithm by selected biochemical and structural features. We conducted this study in two complex subtropical forest areas, Mazongling (MZL) and Gonggashan (GGS) National Nature Forest Reserves using UAV-borne hyperspectral and LiDAR data. The results showed that the classification method performed better with higher values of R2 than the clustering algorithm for predicting both species richness (0.62 > 0.46 for MZL and 0.55 > 0.46 for GGS) and Shannon-Wiener index (0.64 > 0.58 for MZL, 0.52 > 0.47 for GGS). However, the Simpson index estimated by the classification method correlated less with the field measurements than the clustering algorithm (R2 = 0.44 and 0.83 for MZL and R2 = 0.44 and 0.62 for GGS). Our study demonstrated that the classification method could provide more accurate monitoring of forest diversity indices but requires spectral information of all dominant tree species at individual canopy scale. By comparison, the clustering method might introduce uncertainties due to the amounts of biochemical and structural inputs derived from the hyperspectral and LiDAR data, but it could acquire forest diversity patterns rapidly without distinguishing the specific tree species. Our findings underlined the advantages of UAV remote sensing for monitoring the species diversity in complex forest ecosystems and discussed the applicability of classification and clustering methods for estimating different individual tree-based species diversity indices.

Dosage compensation, which is achieved by X-chromosome inactivation (XCI) in female mammals, ensures balanced X-linked gene expression levels between the sexes. Although eutherian mammals commonly display random XCI in embryonic and adult tissues, imprinted XCI has also been identified in extraembryonic tissues of mouse, rat, and cow. Little is known about XCI in pigs. Here, we sequenced the porcine XIST gene and identified an insertion/deletion mutation between Asian- and Western-origin pig breeds. Allele-specific analysis revealed biallelic XIST expression in porcine ICSI blastocysts. To investigate the XCI pattern in porcine placentas, we performed allele-specific RNA sequencing analysis on individuals from reciprocal crosses between Duroc and Rongchang pigs. Our results were the first to reveal that random XCI occurs in the placentas of pigs. Next, we investigated the H3K27me3 histone pattern in porcine blastocysts, showing that only 17-31.8% cells have attained XCI. The hypomethylation status of an important XIST DMR (differentially methylated region) in gametes and early embryos demonstrated that no methylation is pre-deposited on XIST in pigs. Our findings reveal that the XCI regulation mechanism in pigs is different from that in mice and highlight the importance of further study of the mechanisms regulating XCI during early porcine embryo development.

Excess reactive oxygen species (ROS) generated in embryos during in vitro culture damage cellular macromolecules and embryo development. Glutathione (GSH) scavenges ROS and optimizes the culture system. However, how exogenous GSH influences intracellular GSH and improves the embryo developmental rate is poorly understood. In this study, GSH or GSX (a stable GSH isotope) was added to the culture media of bovine in vitro fertilization embryos for 7 days. The cleavage rate, blastocyst rate, and total cell number of blastocysts were calculated. Similarly to GSH, GSX increased the in vitro development rate and embryo quality. We measured intracellular ROS, GSX, and GSH for 0-32-hr postinsemination (hpi) in embryos (including zygotes at G1, S, and G2 phases and cleaved embryos) cultured in medium containing GSX. Intracellular ROS significantly decreased with increasing intracellular GSH in S-stage zygotes (18 hpi) and cleaved embryos (32 hpi). γ-Glutamyltranspeptidase ( GGT) and glutathione synthetase ( GSS) messenger RNA expression increased in zygotes (18 hpi) and cleaved embryos treated with GSH, consistent with the tendency of overall GSH content. GGT activity increased significantly in 18 hpi zygotes. GGT and GCL enzyme inhibition with acivicin and buthionine sulfoximine, respectively, decreased cleavage rate, blastocyst rate, total cell number, and GSH and GSX content. All results indicated that exogenous GSH affects intracellular GSH levels through the γ-glutamyl cycle and improves early embryo development, enhancing our understanding of the redox regulation effects and transport of GSH during embryo culture in vitro.

In this paper, we introduce a multiple threads model for video decoding optimization which automatically adjusts the thread priority among decoding threads, and verify the test results on Marvell ARMADA 610 processor. The test results show that the performance of video decoding is improved about 250% comparing with the single thread model, and about 3.5% faster comparing with traditional multiple threads model on variety hardware environments.

In recent SOPC (System on Programmable Chip) design, a system becomes very complex and the cost of modifying the design during the development becomes very expensive. Based on the technology of the C to HDL (Hardware Description Language), we propose a framework to convert C++ class to hardware, which can be used to cope with the change of design requirement during the development period. Within this framework, software and hardware components can be switched to each other easily, and can be reused between different projects as an object-oriental component.