Contextual Information Aided Generative Adversarial Network for Low-Light Image Enhancement

Low-light image enhancement has been gradually becoming a hot research topic in recent years due to its wide usage as an important pre-processing step in computer vision tasks. Although numerous methods have achieved promising results, some of them still generate results with detail loss and local distortion. In this paper, we propose an improved generative adversarial network based on contextual information. Specifically, residual dense blocks are adopted in the generator to promote hierarchical feature interaction across multiple layers and enhance features at multiple depths in the network. Then, an attention module integrating multi-scale contextual information is introduced to refine and highlight discriminative features. A hybrid loss function containing perceptual and color component is utilized in the training phase to ensure the overall visual quality. Qualitative and quantitative experimental results on several benchmark datasets demonstrate that our model achieves relatively good results and has good generalization capacity compared to other state-of-the-art low-light enhancement algorithms

Effects of Land Use/Cover Changes and Urban Forest Configuration on Urban Heat Islands in a Loess Hilly Region: Case Study Based on Yan’an City, China

In this study Yan’an City, a typical hilly valley city, was considered as the study area in order to explain the relationships between the surface urban heat island (SUHI) and land use/land cover (LULC) types, the landscape pattern metrics of LULC types and land surface temperature (LST) and remote sensing indexes were retrieved from Landsat data during 1990–2015, and to find factors contributed to the green space cool island intensity (GSCI) through field measurements of 34 green spaces. The results showed that during 1990–2015, because of local anthropogenic activities, SUHI was mainly located in lower vegetation cover areas. There was a significant suburban-urban gradient in the average LST, as well as its heterogeneity and fluctuations. Six landscape metrics comprising the fractal dimension index, percentage of landscape, aggregation index, division index, Shannon’s diversity index, and expansion intensity of the classified LST spatiotemporal changes were paralleled to LULC changes, especially for construction land, during the past 25 years. In the urban area, an index-based built-up index was the key positive factor for explaining LST increases, whereas the normalized difference vegetation index and modified normalized difference water index were crucial factors for explaining LST decreases during the study periods. In terms of the heat mitigation performance of green spaces, mixed forest was better than pure forest, and the urban forest configuration had positive effects on GSCI. The results of this study provide insights into the importance of species choice and the spatial design of green spaces for cooling the environment

Relationship between fault activity and hydrocarbon accumulation in the Baxian Depression, Bohai Bay Basin, China

Based on the fluorescence microscopic features of fluid inclusions and the combined analysis of the homogenization temperature and burial history modeling, the hydrocarbon charge history was divided into two phases, among which the second phase was the main pool-forming period and took place during the deposition of the Minghuazhen Formation (12–2 Ma). Based on the calculation of the rate of fault displacement and the duration of fault activity, the fault activity characteristics are quantitatively evaluated. The result shows that the average rate of fault displacement during this interval was 6.9 m/Myr, and the duration of fault activity was about 0–6 Myr. Reservoirs formed in the non-hydrocarbon generating strata are overwhelmingly situated adjacent to the faults which have the most rapid displacement rates and longest periods of activity

Growth Hormone Receptor Gene is Essential for Chicken Mitochondrial Function In Vivo and In Vitro

The growth hormone receptor (GHR) gene is correlated with many phenotypic and physiological alternations in chicken, such as shorter shanks, lower body weight and muscle mass loss. However, the role of the GHR gene in mitochondrial function remains unknown in poultry. In this study, we assessed the function of mitochondria in sex-linked dwarf (SLD) chicken skeletal muscle and interfered with the expression of GHR in DF-1 cells to investigate the role of the GHR gene in chicken mitochondrial function both in vivo and in vitro. We found that the expression of key regulators of mitochondrial biogenesis and mitochondrial DNA (mtDNA)-encoded oxidative phosphorylation (OXPHOS) genes were downregulated and accompanied by reduced enzymatic activity of OXPHOS complexes in SLD chicken skeletal muscle and GHR knockdown cells. Then, we assessed mitochondrial function by measuring mitochondrial membrane potential (ΔΨm), mitochondrial swelling, reactive oxygen species (ROS) production, malondialdehyde (MDA) levels, ATP levels and the mitochondrial respiratory control ratio (RCR), and found that mitochondrial function was impaired in SLD chicken skeletal muscle and GHR knockdown cells. In addition, we also studied the morphology and structure of mitochondria in GHR knockdown cells by transmission electron microscopy (TEM) and MitoTracker staining. We found that knockdown of GHR could reduce mitochondrial number and alter mitochondrial structure in DF-1 cells. Above all, we demonstrated for the first time that the GHR gene is essential for chicken mitochondrial function in vivo and in vitro

Regeneration of Betula albosinensis in strip clearcut and uncut forests of the Qinling Mountains in China.

To contribute to a better understanding of the regeneration strategy of Betula albosinensis forests and the likely reasons behind either the successful recovery or failure after strip clearcutting, we compared the population structures and spatial patterns of B. albosinensis in eight B. albosinensis stands in Qinling Mountains, China. Four cut and four uncut stands were selected, and each sampled using a single large plot (0.25 ha). Results indicated that, on the one hand, B. albosinensis recruitment was scarce (average of 48 stems ha(-1)) in the uncut stands, relative to the mature population (average of 259 stems ha(-1)), suggesting a failure of recruitment. On the other hand, the subsequent regeneration approximately 50 years after the strip clearcutting showed that the density of the target species seedlings and saplings has increased significantly, and the current average density of seedlings and saplings was 156 stems ha(-1). The clumped spatial pattern of B. albosinensis suggested that their regeneration was highly dependent on canopy disturbance. However, recruitment remained poor in the uncut stands because most gaps were small in scale. The successful regeneration of sunlight-loving B. albosinensis after strip clearcutting was attributed to the exposed land and availability of more sunlight. Bamboo density did not influence B. albosinensis recruitment in the uncut stands. However, stand regeneration was impeded after strip clearcutting; thus, removing bamboo is essential in improving the competitive status of B. albosinensis at the later stage of forest regeneration after clearcutting. The moderate severity of disturbance resulting from strip clearcutting reversed the degeneration trend of primary B. albosinensis stands. This outcome can help strike a balance between forest conservation and the demand for wood products by releasing space and exposing the forested land for recruitment. Life history traits and spatiotemporal disturbance magnitude are important factors to consider in implementing effective B. albosinensis regeneration strategies

RGD v2.0: A major update of the ruminant functional and evolutionary genomics database

Ruminant Genome Database (RGD; http://animal.nwsuaf.edu.cn/RGD) provides visualization and analysis tools for ruminant comparative genomics and functional annotations. As more high-quality ruminant genome assemblies have become available, we have redesigned the user interface, integrated and expanded multi-omics data, and developed novel features to improve the database. The new version, RGD v2.0, houses 78 ruminant genomes; 110-species synteny alignments for major livestock (including cattle, sheep, goat) and wild ungulates; 21 012 orthologous gene clusters with Gene Ontology and pathway annotation; ∼8 600 000 conserved elements; and ∼1 000 000 cis-regulatory elements by utilizing 1053 epigenomic data sets. The transcriptome data in RGD v2.0 has nearly doubled, currently with 1936 RNA-seq data sets, and 155 174 phenotypic data sets have been newly added. New and updated features include: (i) The UCSC Genome Browser, BLAT, BLAST and Table Browser tools were updated for six available ruminant livestock species. (ii) The LiftOver tool was newly introduced into our browser to allow coordinate conversion between different ruminant assemblies. And (iii) tissue specificity index, tau, was calculated to facilitate batch screening of specifically expressed genes. The enhanced genome annotations and improved functionality in RGD v2.0 will be useful for study of genome evolution, environmental adaption, livestock breeding and biomedicine

GGVD: A goat genome variation database for tracking the dynamic evolutionary process of selective signatures and ancient introgressions

Understanding the evolutionary history and adaptive process depends on the knowledge that we can acquire from both ancient and modern genomic data. With the availability of a deluge of whole-genome sequencing data from ancient and modern goat samples, a user-friendly database making efficient reuse of these important resources is needed. Here, we use the genomes of 208 modern domestic goats, 24 bezoars, 46 wild ibexes, and 82 ancient goats to present a comprehensive goat genome variation database (GGVD). GGVD hosts a total of ∼41.44 million SNPs, ∼5.14 million indels, 6,193 selected loci, and 112 introgression regions. Users can freely visualize the frequency of genomic variations in geographical maps, selective sweeps in interactive tables, Manhattan plots, or line charts, as well as the heatmap patterns of the SNP genotype. Ancient data can be shown in haplotypes to track the state of genetic variants of selection and introgression events in the early, middle, and late stages. For facilitating access to sequence features, the UCSC Genome Browser, BLAT, BLAST, LiftOver, and pcadapt are also integrated into GGVD. GGVD will be a convenient tool for population genetic studies and molecular marker designing in goat breeding programs, and it is publicly available at http://animal.nwsuaf.edu.cn/GoatVar

Temperature and substrate availability regulate soil respiration in the tropical mountain rainforests, Hainan Island, China

Tropical forest plays a key role in global C cycle; however, there are few studies on the C budget in the tropical rainforests in Asia. This study aims to (i) reveal the seasonal patterns of total soil respiration (R-T), litter respiration (R-L) and soil respiration without surface organic litter (R-NL) in the primary and secondary Asian tropical mountain rainforests and (ii) quantify the effects of soil temperature, soil moisture and substrate availability on soil respiration. The seasonal dynamics of soil CO2 efflux was measured by an automatic chamber system (Li-8100), within the primary and secondary tropical mountain rainforests located at the Jianfengling National Reserve in Hainan Island, China. The litter removal treatment was used to assess the contribution of litter to belowground CO2 production. The annual R-T was higher in the primary forest (16.730.87 Mg C ha(1)) than in the secondary forest (15.100.26 Mg C ha(1)). The rates of R-T, R-NL and R-L were all significantly higher in the hot and wet season (MayOctober) than those in the cool and dry season (NovemberApril). Soil temperature at 5cm depth could explain 5561% of the seasonal variation in R-T, and the temperature sensitivity index (Q(10)) ranked by R-L (Q(10) 3.39) > R-T (2.17) > R-NL (1.76) in the primary forest and by R-L (4.31) > R-T (1.86) > R-NL (1.58) in the secondary forest. The contribution of R-L to R-T was 2223%, while litter input and R-T had 1 month time lag. In addition, the seasonal variation of R-T was mainly determined by soil temperature and substrate availability. Our findings suggested that global warming and increased substrate availability are likely to cause considerable losses of soil C in the tropical forests.Plant SciencesEcologySCI(E)3ARTICLE5325-334

WGVD: An integrated web-database for wheat genome variation and selective signatures

Bread wheat is one of the most important crops worldwide. With the release of the complete wheat reference genome and the development of next-generation sequencing technology, a mass of genomic data from bread wheat and its progenitors has been yield and has provided genomic resources for wheat genetics research. To conveniently and effectively access and use these data, we established Wheat Genome Variation Database, an integrated web-database including genomic variations from whole-genome resequencing and exome-capture data for bread wheat and its progenitors, as well as selective signatures during the process of wheat domestication and improvement. In this version, WGVD contains 7 346 814 single nucleotide polymorphisms (SNPs) and 1 044 400 indels focusing on genic regions and upstream or downstream regions. We provide allele frequency distribution patterns of these variations for 5 ploidy wheat groups or 17 worldwide bread wheat groups, the annotation of the variant types and the genotypes of all individuals for 2 versions of bread wheat reference genome (IWGSC RefSeq v1.0 and IWGSC RefSeq v2.0). Selective footprints for Aegilops tauschii, wild emmer, domesticated emmer, bread wheat landrace and bread wheat variety are evaluated with two statistical tests (FST and Pi) based on SNPs from whole-genome resequencing data. In addition, we provide the Genome Browser to visualize the genomic variations, the selective footprints, the genotype patterns and the read coverage depth, and the alignment tool Blast to search the homologous regions between sequences. All of these features of WGVD will promote wheat functional studies and wheat breeding. Database URL: http://animal.nwsuaf.edu.cn/code/index.php/Wheat

Population structure and spatial pattern of predominant tree species in a pine–oak mosaic mixed forest in the Qinling Mountains, China

This study investigated a typical pine-oak mosaic mixed forest in the Qinling Mountains, China. In the sample plot, the population structure and spatial distribution of the stems were analyzed for the predominant species, to identify the mechanisms of species coexistence and successional trends of the forest. The population structures of all species were bimodally distributed, with young trees (DBH <1 cm) more abundant than older trees. The population structures of Quercus aliena var. acuteserrata was bimodal and rather continuous. However, Pinus tabuliformis and Pinus armandii were discontinuously bimodal, with distinct size deficiencies. Q. aliena var. acuteserrata trees were clumped throughout the plot, although those of P. tabuliformis and P. armandii were clumped at small scales. Notable negative spatial associations between Q. aliena var. acuteserrata and P. tabuliformis were found at almost scales. P. armandii and Q. aliena var. acuteserrata were negatively spatially associated at small scales but positively associated at large scales. Our findings suggest that interspecific competition gradually develops among the predominant tree species. The dynamics of the pine-oak mosaic mixed forest formed a mosaic distribution of uniformly mixed types, with the slow infiltration of Q. aliena var. acuteserrata populations that would eventually establish a pure stand