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The peel stripe margin pattern is one of the most important quality traits of watermelon. In this study, two contrasted watermelon lines [slb line (P1) with a clear peel stripe margin pattern and GWAS-38 line (P2) with a blurred peel stripe margin pattern] were crossed, and biparental F2 mapping populations were developed. Genetic segregation analysis revealed that a single recessive gene is modulating the main-effect genetic locus (Clcsm) of the clear stripe margin pattern of peel. Bulked segregant analysis-based sequencing (BSA-Seq) and fine genetic mapping exposed the delimited Clcsm locus to a 19.686-kb interval on chromosome 6, and the Cla97C06G126680 gene encoding the MYB transcription factor family was identified. The gene mutation analysis showed that two non-synonymous single-nucleotide polymorphism (nsSNP) sites [Chr6:28438793 (A-T) and Chr6:28438845 (A-C)] contribute to the clear peel stripe margin pattern, and quantitative real-time polymerase chain reaction (qRT-PCR) also showed a higher expression trend in the slb line than in the GWAS-38 line. Further, comparative transcriptomic analysis identified major differentially expressed genes (DEGs) in three developmental periods [4, 12, and 20 days after pollination (DAP)] of both parental lines. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment analyses indicated highly enriched DEGs involved in metabolic processes and catalytic activity. A total of 44 transcription factor families and candidate genes belonging to the ARR-B transcription factor family are believed to regulate the clear stripe margin trait of watermelon peel. The gene structure, sequence polymorphism, and expression trends depicted significant differences in the peel stripe margin pattern of both parental lines. The ClMYB36 gene showed a higher expression trend for regulating the clear peel stripe margin of the slb line, and the ClAPRR5 gene depicted a higher expression for modulating the blurred peel stripe margin in the GWAS-38 line. Overall, our fine genetic mapping and transcriptomic analysis revealed candidate genes differentiating the clear and blurred peel stripe patterns of watermelon fruit.

Diamond, a wide bandgap semiconductor material, has excellent physicochemical properties. It has great potential for application in high temperature, high frequency, high power electronic devices and other high technology fields. In order to study the electronic properties of diamond more precisely, an AM-response surface model is developed in this paper to investigate the electronic structures of diamond, P-doped diamond and N-doped diamond surfaces in depth. It is shown that there are three forms of charge states in the single vacancy on the diamond surface. When E=0 V, the negative charge energy level is -0.5 mV, the positive charge is 1 mV, and the zero level remains 0. And its energy level is unstable. In contrast, the double vacancy charge on the diamond surface varies depending on the valence band taken by E, and only one charge state exists. When E0, it is positive charge energy level. The electronic properties of the P-doped diamond semiconductor material are calculated to have a constant positive charge (1 mV). The electronic property of N-doped diamond semiconductor material is constant negative charge (-1mV).

The occurrence of cyanobacterial blooms in summer are frequently accompanied by the succession of phytoplankton communities in freshwater. However, little is known regarding the roles of viruses in the succession, such as in huge reservoirs. Here, we investigated the viral infection characteristics of phytoplankton and bacterioplankton during the summer bloom succession in Xiangxi Bay of Three Gorges Reservoir, China. The results indicated that three distinct bloom stages and two successions were observed. From cyanobacteria and diatom codominance to cyanobacteria dominance, the first succession involved different phyla and led to a Microcystis bloom. From Microcystis dominance to Microcystis and Anabaena codominance, the second succession was different Cyanophyta genera and resulted in the persistence of cyanobacterial bloom. The structural equation model (SEM) showed that the virus had positive influence on the phytoplankton community. Through the Spearman’s correlation and redundancy analysis (RDA), we speculated that both the increase of viral lysis in the eukaryotic community and the increase of lysogeny in cyanobacteria may contributed to the first succession and Microcystis blooms. In addition, the nutrients supplied by the lysis of bacterioplankton might benefit the second succession of different cyanobacterial genera and sustain the dominance of cyanobacteria. Based on hierarchical partitioning method, the viral variables still have a marked effect on the dynamics of phytoplankton community, although the environmental attributes were the major factors. Our findings suggested that viruses played multiple potential roles in summer bloom succession and may help the blooms success of cyanobacteria in Xiangxi Bay. Under the background of increasingly serious cyanobacterial blooms worldwide, our study may have great ecological and environmental significance for understanding the population succession in phytoplankton and controlling the cyanobacterial blooms.

It is generally recognized that agricultural soils accumulate toxic metals after long-term wastewater irrigation. The removal of trace metals (TMs) from the soil is not possible. Therefore, this study investigated the effects of the addition of manure on the extractability and bioavailability of TM from the contaminated soil after wastewater irrigation. Soils samples were treated with co-composted cow manure (CM) and poultry litter (PL) at 10 and 20 t ha−1. The study showed that addition of manure enhanced fenugreek biomass and reduced TM uptake depending on the combination of composted manures used. TM concentrations in the fenugreek shoots varied in the order of Pb > Ni > Zn > Cu > Cd. A higher amount of manure mixture especially composted with the privet and cypress residues decreased the extractability of TM from the contaminated soil. Soils amended with PL reduced TM concentrations more than CM; this is also true for the plant uptake. The variation of TM in plants was positively associated with their concentrations in the soil and adversely related to the plant biomass. This study confirmed that the combined use of composted manure with plant residues can be an effective addition for ameliorating the TM pollution in soils and crops.

BackgroundIt is well known that the clivus is composed of abundant cancellous bone and is often invaded by pituitary adenoma (PA), but the range of these cancellous bone corridors is unknown. In addition, we found that PA with clivus invasion is sometimes accompanied by petrous apex invasion, so we speculated that the petrous apex tumor originated from the clivus cancellous bone corridor. The aim of this study was to test this hypothesis by investigating the bony anatomy associated with PA with clival invasion and its clinical significance.MethodsTwenty-two cadaveric heads were used in the anatomical study to research the bony architecture of the clivus and petrous apex, including six injected specimens for microsurgical dissection and sixteen cadavers for epoxy sheet plastination. The surgical videos and outcomes of PA with clival invasion in our single center were also retrospectively reviewed.ResultsThe hypoglossal canal and internal acoustic meatus are composed of bone canals surrounded by cortical bone. The cancellous corridor within clivus starts from the sellar or sphenoid sinus floor and extends downward, bypassing the hypoglossal canal and finally reaching the occipital condyle and the medial edge of the jugular foramen. Interestingly, we found that the cancellous bone of the clivus was connected with that of the petrous apex through petroclival fissure extending to the medial margin of the internal acoustic meatus instead of a separating cortical bone between them as it should be. It is satisfactory that the anatomical outcomes of the cancellous corridor and the path of PA with clival invasion observed intraoperatively are completely consistent. In the retrospective cohort of 49 PA patients, the clival component was completely resected in 44 (89.8%), and only five (10.2%) patients in the early-stage had partial residual cases in the inferior clivus.ConclusionThe petrous apex invasion of PA is caused by the tumor invading the clivus and crossing the petroclival fissure along the cancellous bone corridor. PA invade the clivus along the cancellous bone corridor and can also cross the hypoglossal canal to the occipital condyle. This clival invasion pattern presented here deepens our understanding of the invasive characteristics of PA.

Forest ecosystems are characterized by the largest terrestrial carbon (C) stocks, play a vital role in global C cycle. Numerous previous studies have documented soil C accumulation and its related contributory factors, and have highlighted the soil physical structure, particularly soil aggregates, as a potential key factor determining the accumulation of C in grasslands or farmlands. At present, however, comparatively little is known regarding the soil aggregation and organic C distribution in plantations following forest management. In this study, we sought to identify the effects of forest management on soil aggregation and organic C distribution in Pinus massoniana plantations in the Three Gorges Reservoir area of China. To this end, we compared soil water-stable aggregates (WSAs), organic C distribution, and organic C chemical composition in the 0–10 cm soil layer of forest plots subjected to the following four treatments: unmanaged intact forest (control: CK), low-intensity thinning (15% thinning: LIT), high-intensity thinning (70% thinning: HIT), and understory removal (all understory shrubs removed: SR). The results indicated that the plantation soil was clearly characterized by macroaggregate and microaggregate structures. Among the WSAs, aggregates ranging in size from 250 to 2000 µm had the highest weight proportion (46.78%–53.87%), whereas silt plus clay-sized particles (

An experiment was conducted to evaluate the embryonic lipid deposition in yolk, embryo serum and tissues during the late laying period of Arbor Acres broiler breeder hens fed diets (21–60 weeks) with different levels of ME, 2.80 Mcal/kg (ND), 2.24 Mcal/kg (LD20) and 1.96 Mcal/kg (LD30) in a completely randomised experimental design. At 60 weeks of age, 100 fertile eggs in each group were collected and hatched. The results showed that low dietary energy decreased egg weight and egg content weight significantly, and embryo weight in LD20 was highest. Serum cholesterol level in LD20 (on each embryonic day) was significantly higher than those in other two groups. As the dietary energy level decreased, serum triglycerides level was decreased significantly, and serum low-density lipoprotein-cholesterol level was increased significantly. Serum high-density lipoprotein-cholesterol level was higher in LD30 than in other two groups on embryonic days 13, 15, 17 and 19, but higher in LD20 on embryonic day 21. In LD20, cholesterol level in the breast muscle and liver tissues and crude fat content in the breast muscle tissues were significantly higher than those in other two groups. LD30 got a lower cholesterol level in the thigh muscle tissues than ND. These results indicate that maternal dietary energy restriction directly affected lipid metabolism in embryos at the end of the laying period.

Aquatic vegetation in shallow freshwater lakes are severely degraded worldwide, even though they are essential for inland ecosystem services. Detailed information about the long term variability of aquatic plants can help investigate the potential driving mechanisms and help mitigate the degradation. In this paper, based on Google Earth Engine cloud-computing platform, we made use of a 33-year (1987–2019) retrospective archive of moderate resolution Landsat TM, ETM + and OLI satellite images to estimate the extent changes in aquatic vegetation in Longgan Lake from Middle Yangtze River Basin in China using the modified enhanced vegetation index, including emerged, floating-leaved and floating macrophytes. The analysis of the long term dynamics of aquatic vegetation showed that aquatic vegetation were mainly distributed in the western part of the lake, where lake bottom elevation ranged from 11 to 12 m, with average water depth of less than 1 m in spring. The vegetation area variation for the 33-year period were divided into six stages. In years with heavy precipitation, the vegetation area decreased sharply. In the following years, the area normally restored. Aquatic vegetation area had a significant negative correlation with the spring water level and summer water level. The results showed that aquatic vegetation was negatively affected when water depth exceeded 2.5 m in May and 5 m in summer. It is recommended that water depth remain close to 1 m in spring and close to 3 m in summer for aquatic vegetation growth. Our study provide quantitative evidence that water-level fluctuations drive vegetation changes in Longgan Lake, and present a basis for sustainable lake restoration and management.

The lake ecosystems on the Yunnan-Guizhou Plateau in China have degraded in recent decades under the effects of anthropogenic activities and climate change. The human impact on the oligotrophic Lugu Lake aquatic ecosystem was evaluated using the sediment records of metals, nitrogen isotopes (δ15N) and magnetic susceptibility over the past 200 years. Three periods were identified based on the trace metal and δ15N records. During the first stage (1816–1976 AD), the concentrations of metals, δ15N and magnetic susceptibility were low with small variations. The anthropogenic contributions to the inputs were also small, except for Ni, reflecting minor human activities in the watershed, and no significant change was observed in the sediment record of the diatom assemblage. During the second stage (1976–2001 AD), the concentrations of Zn and δ15N increased, as well as the anthropogenic contribution of Zn. However, no significant change was detected in the anthropogenic sources of the other metals. These results reflect the low-level use of chemical fertilizers. The major shift in the sediment diatom assemblage during this stage was mainly attributed to regional climate change. During the third stage (2001–2010 AD), the concentrations of the sedimentary metals (Ni, Cr, Mn, Cu, Hg and Al) increased rapidly, with the exception of As and Zn, and a similar increasing trend was observed in the changes by anthropogenic sources of Ni, Cr, Mn and Cu. RDA (Redundancy Analysis) and variance partitioning analysis showed that the human impact and climate proxies independently explained 31.59% and 4.26% of the change of diatom community, respectively, and the interaction between climate change and human impact accounted for 18.61% of the change of diatom community. Tourism-dominated human activities, which were reflected in the metals profiles, facilitated the dominance of eutrophic species and reduced that of oligotrophic species. The development of tourism was likely the main driving force for the succession of diatom assemblages in the third stage. In summary, the anthropogenic input of trace metals in Lugu Lake is still at a low level. However, the significant growth trend in metals over the past decade is significantly related to the change in the lake ecosystem. Therefore, the effects of human activities, especially tourism, on the watershed should be controlled for the protection of the oligotrophic Lugu Lake.

Electric furnace roof is an important device for electric steel making, whose heat preservation performance and life-span have a direct impact on the economic benefits of iron and steel enterprise. This paper investigates the effect between the stress level of electric furnace roof and the material parameters. Research indicates that they have a trend to change in the same direction.

Long-term information of phytoplankton bloom is critical for assessing the processes driving blooms in lakes. A three-decade survey of the phytoplankton blooms was completed for Erhai Lake from 1987 to 2016 with Landsat imagery. A modified three-band model using Landsat broad bands is developed by comparing reflectance data from Landsat imagery to two field datasets. The model is applied to the archived imagery (1987–2016) to predict chlorophyll-a (Chl-a). Predicted ln(Chl-a) and observed ln(Chl-a) measurements are significantly correlated (R2 = 0.70; RMSE = 0.13 ug/L). Bloom maps are generated by identifying Landsat pixels that have Chl-a concentrations larger than 20 ug/L as bloom area. Bloom extent and magnitude are estimated. Our study reveals that algal blooms first occurred in 1996 with a bloom area of 150 km2. Bloom occurred frequently from 2002 to 2016, with extreme blooms in 2003, 2013 and 2016. Algal blooms were mostly distributed in the northern and southern part of the lake. The proposed method uses one model for all Landsat images for Erhai Lake and can predict past blooms and extend the record to early years when field data is not available. The bloom extent and magnitude produced in this study can be used as the basis for the understanding of the processes that control the bloom outbreak.

Fine roots play an important role in plant growth as well as carbon (C) and nutrient cycling in terrestrial ecosystems. Fine roots are important for understanding the contribution of forests to the global C cycle. Knowledge about this topic is still limited, especially regarding the effects of different forest management practices. This study investigated the seasonal dynamics of fine roots (

Several studies have focused on fine roots characteristics because they provide a major pathway for nutrient cycling and energy flow in forest ecosystems. However, few studies have evaluated changes in fine root characteristics according to their diameter. Pinus massoniana forests are the main vegetative component in the Three Gorges Reservoir area and play an important role in providing forest resources and ecological services. Pinus massoniana fine roots were sorted into 0–0.5, 0.5–1, and 1–2 mm diameter classes, and their fine root standing biomass (FRB), necromass, annual production and decomposition rates were determined and correlated with soil characteristics. These fine roots in three diameter classes significantly differed in their initial carbon (C), C/N ratio, FRB, necromass, annual C and N production and decomposition rate. The production and decomposition of these different diameter classes varied significantly with soil variables including soil temperature, moisture, calcium and ammonium concentration but the strength of these interactions varied dependent on diameter class. The very fine roots had a faster decomposition ratio than larger fine roots due to the lower N content, higher C/N ratio and higher sensitivity to soil environmental factors. These results clearly indicate heterogeneity among fine roots of different diameters, and these variations should be taken into account when studying fine root characteristics and their role in the C cycle.

TRK fusions are rare but targetable mutations which occur across a wide variety of cancer types. We report the prevalence of approximately 0.7% for NTRK-positive colorectal cancer (CRC) by genetically profiling 2519 colonic and rectal tumors. The aberrations of APC and TP53 frequently co-occurred with NTRK gene fusions, whereas RAS/BRAF oncogenic alterations and NTRK fusions were almost always mutually exclusive. NTRK-driven colorectal cancer patients demonstrated increased TMB (median = 53 mut/MB, 95% CI: 36.8-68.0 mut/MB), high microsatellite instability, and an enrichment for POLE/POLD1 mutations when compared to molecularly unstratified colorectal cancer population. These data shed light on possible future approach of multimodality treatment regimen including TRK-targeted therapy and immune checkpoint inhibitor therapy in NTRK-positive CRCs.