Differential DNA methylation of the paternal and maternal alleles regulates the parental origin-specific expression of imprinted genes in mammals. The methylation imprints are established in male and ...female germ cells during gametogenesis, and the de novo DNA methyltransferase DNMT3A and its cofactor DNMT3L are required in this process. However, the mechanisms underlying locus- and parental-specific targeting of the de novo DNA methylation machinery in germline imprinting are poorly understood. Here we show that amine oxidase (flavin-containing) domain 1 (AOF1), a protein related to the lysine demethylase KDM1 (also known as LSD1), functions as a histone H3 lysine 4 (H3K4) demethylase and is required for de novo DNA methylation of some imprinted genes in oocytes. AOF1, now renamed lysine demethylase 1B (KDM1B) following a new nomenclature, is highly expressed in growing oocytes where genomic imprints are established. Targeted disruption of the gene encoding KDM1B had no effect on mouse development and oogenesis. However, oocytes from KDM1B-deficient females showed a substantial increase in H3K4 methylation and failed to set up the DNA methylation marks at four out of seven imprinted genes examined. Embryos derived from these oocytes showed biallelic expression or biallelic suppression of the affected genes and died before mid-gestation. Our results suggest that demethylation of H3K4 is critical for establishing the DNA methylation imprints during oogenesis.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Power generating technology based on renewable energy resources will definitely become a new trend of future energy utilization. Numerical simulations on air flow, heat transfer and power output ...characteristics of a solar chimney power plant model with energy storage layer and turbine similar to the Spanish prototype were carried out in this paper, and mathematical model of flow and heat transfer for the solar chimney power plant system was established. The influences of solar radiation and pressure drop across the turbine on the flow and heat transfer, output power and energy loss of the solar chimney power plant system were analyzed. The numerical simulation results reveal that: when the solar radiation and the turbine efficiency are 600
W/m
2 and 80%, respectively, the output power of the system can reach 120
kW. In addition, large mass flow rate of air flowing through the chimney outlet become the main cause of energy loss in the system, and the collector canopy also results in large energy loss.
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GEOZS, IJS, IMTLJ, KISLJ, NUK, OILJ, SAZU, SBCE, UL, UM, UPCLJ, UPUK
The removal of understory vegetation has been a common forest management practice, especially in plantations, but the effects of understory removal on soil physico-chemical properties and decomposer ...organisms is poorly known. In the present study, the effects of understory vegetation removal and removal of all-plants (i.e. removal of understory vegetation and trees) on soil properties and soil biota were measured in a plantation of mixed native tree species in southern China. During the wet season, understory vegetation removal did not cause significant changes on soil microbial community and major soil faunal groups except for a marked reduction in the density of herbivorous nematodes. However, all-plants removal significantly decreased the fungal biomass, the fungal:bacterial ratio, the density of herbivorous nematodes, the structure of the nematode community, and the density of mites, collembola and total microarthropods. In the dry season, understory vegetation removal resulted in a marked reduction in the density of total and herbivorous nematodes. The effects of plant removal on soil biota were similar to that in dry season. For both seasons, understory removal had no significant effects on soil physico-chemical properties (soil water content, pH, total nitrogen and soil organic carbon) but removal of all-plants significantly decreased soil pH. In general, the effects of understory vegetation removal on soil biota and other soil properties were much less severe than those of all-plants removal. The soil biota did not show significant response to understory removal, suggesting that this part of the vegetation may not be a major governing factor on such biota.
► Removal of all-plants significantly changed soil pH and biological properties. ► Removal of understory vegetation did not change soil physico-chemical properties. ► Understory removal showed some mild effects on soil organisms. ► Understory removal had different effects on different groups of soil organisms. ► Understory vegetation may not be a major governing factor on such biota.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Nowdays, DNNs (Deep Neural Networks) are widely used in the field of DDoS attack detection. However, designing a good DNN architecture relies on the designer’s experience and requires considerable ...work. In this paper, a GA (genetic algorithm) is used to automatically generate the DNN architecture for DDoS detection to minimize human intervention in the design process. Furthermore, given the complexity of contemporary networks and the diversity of DDoS attacks, the objective of this paper is to generate a DNN model that boasts superior performance, real-time capability, and generalization ability to tackle intricate network scenarios. This paper presents a fitness function that guarantees the best model generated possesses a specific level of real-time capability. Additionally, the proposed method employs multiple datasets to joint models generated, thereby enhancing the model’s generalization performance. This paper conducts several experiments to validate the viability of the proposed method. Firstly, the best model generated with one dataset is compared with existing DNN models on the CICDDoS2019 dataset. The experimental results indicate that the model generated with one dataset has higher precision and F1-score than the existing DNN models. Secondly, model generation experiments are conducted on the CICIDS2017 and CICIDS2018 datasets, and the best model generated still performs well. Finally, this paper conducts comparative experiments on multiple datasets using the best model generated with six datasets and the best model generated by existing methods. The experimental results demonstrate that the best model generated with six datasets has better generalization ability and real-time capability.
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CEKLJ, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Chronic renal failure (CRF) is a major public health problem worldwide. Hydrogen sulfide (H
S) plays important roles in renal physiological and pathophysiological processes. However, whether H
S ...could protect against CRF in rats remains unclear. In this study, we found that H
S alleviated gentamicin-induced nephrotoxicity by reducing reactive oxygen species (ROS)-mediated apoptosis in normal rat kidney-52E cells. We demonstrated that H
S significantly improved the kidney structure and function of CRF rats. We found that H
S decreased the protein levels of Bax, Caspase-3, and Cleaved-caspase-3, but increased the expression of Bcl-2. Treatment with H
S reduced the levels of malondialdehyde and ROS and increased the activities of superoxide dismutase and glutathione peroxidase. H
S significantly abolished the phosphorylation of extracellular signal-regulated protein kinase 1/2, c-Jun N-terminal kinase, and p38 in the kidney of CRF rats. Furthermore, H
S decreased the expression levels of tumor necrosis factor-α, interleukin (IL)-6, IL-10, and monocyte chemoattractant protein-1, as well as the protein levels of p50, p65, and p-p65 in the kidney of CRF rats. In conclusion, H
S could ameliorate adenine-induced CRF in rats by inhibiting apoptosis and inflammation through ROS/mitogen-activated protein kinase and nuclear factor-kappa B signaling pathways.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
We develop a local birefringence determination method of measuring the distribution of external force-induced birefringence in spun high-birefringence (HiBi) fiber (spun HiBi fiber) using ...polarimetric optical frequency domain reflectometry (P-OFDR). By constructing the similarity between the measured Mueller matrices and fiber under test (FUT) matrices using two input states of polarization, the total phase retardance caused by the local birefringence of FUT can be determined from the trace of the measured matrices. We measure the local birefringence of spun HiBi fibers from two different manufacturers and telecom SMF (G652.D) caused by bending, twist, and transverse stress using our presented P-OFDR system. From the experimental results, we find that bending- and twist-induced birefringences of spun HiBi fiber are much lower than those of standard SMF. More remarkably, the coating package influences the transverse stress induced birefringence of spun HiBi fibers significantly. These experimental results verify that our presented method is beneficial to evaluating and improving spun HiBi fibers' quality.
Ten-Eleven Translocation (Tet) family of dioxygenases dynamically regulates DNA methylation and has been implicated in cell lineage differentiation and oncogenesis. Yet their functions and mechanisms ...of action in gene regulation and embryonic development are largely unknown. Here, we report that Xenopus Tet3 plays an essential role in early eye and neural development by directly regulating a set of key developmental genes. Tet3 is an active 5mC hydroxylase regulating the 5mC/5hmC status at target gene promoters. Biochemical and structural studies further demonstrate that the Tet3 CXXC domain is critical for specific Tet3 targeting. Finally, we show that the enzymatic activity and CXXC domain are both crucial for Tet3’s biological function. Together, these findings define Tet3 as a transcription regulator and reveal a molecular mechanism by which the 5mC hydroxylase and DNA binding activities of Tet3 cooperate to control target gene expression and embryonic development.
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► Tet3 regulates key genes essential for eye and neural development in Xenopus ► Tet3 regulates gene expression partly via modulating 5mC/5hmC status at the promoter ► Tet3 CXXC domain processes unique DNA binding properties critical for Tet3 targeting ► Both the CXXC domain and hydroxylase activity are required for Tet3 function
Xenopus Tet3 CXXC domain exhibits a unique DNA binding mode and is critical for its targeting. The DNA binding and 5mC hydroxylase activities of Tet3 cooperate to control the expression of key genes in early eye and neural development.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
As a noble-metal-free catalyst for CO oxidation, SnO
2
has sparked worldwide interest owing to its highly reactive lattice oxygen atoms and low cost. The current density functional theory (DFT) ...results demonstrate the process of CO oxidation by lattice oxygen on the SnO
2
(110) surface and the recovery of the reduced surface by O
2
. It is found that CO can be easily oxidized on the SnO
2
(110) surface following the Mars-van Krevelen mechanism. The adsorbed oxygen turns into various oxygen species by transferring electron(s) to the chemisorbed oxygen, which is only found on the partially reduced SnO
2−
x
surface, but not on the perfect SnO
2
(110) surface: O
2
(gas) ↔ O
2
(ad) ↔ O
2
−
(ad) ↔ O
2
2−
(ad) ↔ O
2−
(lattice) + O
−
(ad). The calculated stretching frequencies would help to distinguish the various adsorbed species observed in experiment and of course help in the assignment of vibrational modes in the experimental spectra.
The process of CO oxidation by lattice oxygen on the SnO
2
(110) surface and the recovery of the reduced surface by O
2
is presented.
In this paper, we propose to apply data augmentation approaches that provide more diverse training images, thus helping train more robust deep models for the Scene Text Recognition (STR) task. The ...data augmentation methods are Random Blur Region (RBR) and Random Blur Units (RBUs). Specifically, we first introduce RBR designed for the STR task. In training, RBR randomly selects a region and sets the pixels in this region with an average value. However, when RBR provides more various training samples for STR, it may make the samples ambiguous and reduce the recognition accuracy. To address the above problem, we also propose RBUs that divides the blur region into several units. Note that the pixels of one unit share the same value. In this way, RBUs can provide additional readable training samples and help train more robust deep models. Extensive experiments on several STR datasets show that RBUs achieve highly competitive performance. Besides, RBUs are complementary to commonly used data augmentation techniques.
With the rapid development of e-commerce, online consumption has become a mainstream form of consumption in recent years. Text sentiment analysis for a large number of customer reviews on the ...e-commerce platform can dramatically improve the customers' consumption experience. Although the sentiment analysis approaches based on deep neural network can achieve higher accuracy without human-design features compared with traditional sentiment analysis methods, the accuracy still cannot meet the demand and the training suffers from the issues of over-fitting, vanishing gradient, etc. In this paper, a novel sentiment analysis model named MBGCV is designed to alleviate these problems and improve the accuracy, MBGCV employs a multichannel paradigm and integrates Bidirectional Gated Recurrent Unit (BiGRU), Convolutional Neural Network (CNN) and Variational Information Bottleneck (VIB). The multichannel is exploited to extract multi-grained sentiment features. In each channel, BiGRU is utilized to extract context information, and then CNN is adopted to extract local features. Furthermore, the model combines the advantages of VIB and Maxout activation function to overcome shortcomings such as over-fitting, vanishing gradient in existing sentiment analysis models. By using real review datasets, we carry out extensive experiments to demonstrate that our proposed model can achieve superior accuracy and improve the performance of text sentiment analysis.
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