A new species of Populus and the extensive hybrid speciation arising from it on the Qinghai-Tibet Plateau.

While the diversity of species formation is broadly acknowledged, significant debate exists regarding the universal nature of hybrid species formation. Through an 18-year comprehensive study of all Populus species on the Qinghai-Tibet Plateau, 23 previously recorded species and 8 new species were identified. Based on morphological characteristics, these can be classified into three groups: species in section Leucoides, species with large leaves, and species with small leaves in section Tacamahaca. By conducting whole-genome re-sequencing of 150 genotypes from these 31 species, 2.28 million single nucleotide polymorphisms (SNPs) were identified. Phylogenetic analysis utilizing these SNPs not only revealed a highly intricate evolutionary network within the large-leaf species of section Tacamahaca but also confirmed that a new species, P. curviserrata, naturally hybridized with P. cathayana, P. szechuanica, and P. ciliata, resulting in 11 hybrid species. These findings indicate the widespread occurrence of hybrid species formation within this genus, with hybridization serving as a key evolutionary mechanism for Populus on the plateau. A novel hypothesis, "Hybrid Species Exterminating Their Ancestral Species (HSEAS)," is introduced to explain the mechanisms of hybrid species formation at three different scales: the entire plateau, the southeastern mountain region, and individual river valleys.

A model of hybrid speciation process drawn from three new poplar species originating from distant hybridization between sections.

Although numerous studies have been conducted on hybrid speciation, our understanding of this process remains limited. Through an 18-year systematic investigation of all taxa of Populus on the Qinghai-Tibet Plateau, we discovered three new taxa with clear characteristics of sect. Leucoides. Further evidence was gathered from morphology, whole-genome bioinformatics, biogeography, and breeding to demonstrate synthetically that they all originated from distant hybridization between sect. Leucoides and sect. Tacamahaca. P. gonggaensis originated from the hybridization of P. lasiocarpa with P. cathayana, P. butuoensis from the hybridization of P. wilsonii with P. szechuanica, and P. dafengensis from the hybridization of P. lasiocarpa with P. szechuanica. Due to heterosis, the three hybrid taxa possess greater ecological adaptability than their ancestral species. We propose a hybrid speciation process model that incorporates orthogonal, reverse, and backcrossing events. This model can adequately explain some crucial evolutionary concerns, such as the nuclear-cytoplasmic conflict on phylogeny and the extinction of ancestral species within the distribution range of hybrid species.

Parapapillary ßBM and γ Zones Played Different Roles in Axial Elongation Among Young Adolescents Using Optical Coherence Tomography.

Purpose: To evaluate the influencing factors of parapapillary ßBM and γ zones incidence in young adolescents and to explore their associations with axial length progression. Methods: In this prospective cohort study, 976 seventh-grade students from nine secondary schools in Beijing, China, were enrolled and followed up 1 year later. Parapapillary ßBM zone was defined as retinal pigment epithelium loss while Bruch's membrane was present. Parapapillary γ zone was defined as the absence of retinal pigment epithelium and Bruch's membrane. Logistic regression model was used to analyze the influencing factors of ßBM and γ zone incidence. A linear mixed model was used to analyze the associations between parapapillary zones and axial elongation. Results: Of the 976 participants, 139 (14.2%) had only ßBM zone, 398 (40.8%) had only γ zone, and 171 (17.5%) had both. At follow-up, the incidence of ßBM zone was 11.5% (76/659), and the incidence of γ zone was 9.7% (39/404). Optic disc tilt, thinner subfoveal choroid, and longer axial length at baseline showed a higher risk of γ zone incidence. The absence of γ zone at baseline showed a faster axial length progression. When the baseline axial length was 25 mm or longer, the ßBM zone was also related to the axial elongation. Conclusions: The γ zone was associated with axial length progression, and the ßBM zone was also associated with the axial length progression when the axial length exceeded 25 mm, which was consistent with the notion that excessive axial length growth not only is the extension of the eyeball but also has its own pathologic changes.

Integrating physiological and transcriptome analyses clarified the molecular regulation mechanism of PyWRKY48 in poplar under cadmium stress.

WRKY transcription factors (TFs) play an important role in regulating plant growth and responses to environmental stress. However, the molecular mechanism of WRKY to cadmium (Cd) stress is unclear, which prevents phytoremediation of Cd-contaminated soil from widely application. To determine the underlying mechanism, PyWRKY48-overexpressing poplars were obtained (OE-32 and OE-67) to study the Cd tolerance and accumulation in poplars. Results showed that the Cd content in the aboveground part of the two transgenic poplar lines were 1.57 and 1.99 times higher than that of wild type (WT), and lateral roots, GSH, PCs content and GST activity increased significantly. RNA-seq. data about transgenic and WT poplars revealed that 2074 differentially expressed genes (DEGs) in roots, 4325 in leaves, and 499 in both tissues. And these DEGs were mainly concentrated in ABC transport protein (PaABC), heavy-metal binding protein (PaHIPP), and transportation and loading of xylem (PaNPF, PaBSP) proteins, and they enhanced Cd accumulation. Meanwhile, PyWRKY48 increased the Cd tolerance of transgenic poplars by up-regulating the expression of PaGRP, PaPER and PaPHOS, which encode cell wall proteins, antioxidant enzyme, and heavy metal-associated proteins, respectively. In addition, overexpression PyWRKY48 promoted poplar growth by increasing the chlorophyll and carotenoid content. ENVIRONMENTAL IMPLICATION: This study generated PyWRKY48-overexpressing poplars and functionally verified them in Cd-contaminated soil, to analyze the effects of the gene on poplar growth, Cd tolerance and Cd accumulation. RNA seq. data revealed that several genes are involved in Cd exposure. This may provide a strong molecular basis and new ideas for improving the phytoremediation efficiency of Cd-contaminated soils. Importantly, the transgenic poplars grew better and accumulated more Cd than the wild-type. Therefore, PyWRKY48-overexpressing poplars could be considered useful for mitigating environmental pollution.

Elevated expression of TNFRSF4 impacts immune cell infiltration and gene mutation in hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is a highly heterogeneous disease, which makes prognostic prediction challenging.We aimed to investigate association of TNFRSF4 expression with the immune infiltration and gene mutation in HCC. METHODS: In this study, the expression profiles and corresponding clinical data of HCC patients were downloaded from the Cancer Genome Atlas (TCGA) database.Kaplan-Meier and Cox regression were used to evaluate the clinical value of TNFRSF4. ESTIMATE and CIBERSORT algorithms were applied to investigate the infiltration ratio of 22 immune cells. The WGCNA and LASSO COX algorithms were performed, establishing a prognostic risk model that was then validated by HCC samples from GEO. Finally, the effects on gene mutation occurring in HCC patients of TNFRSF4 expression and risk score were appraised. RESULTS: In HCC tissues, it was found the TNFRSF4 expression profile was significantly different with age, gender, tumor grade, disease stage, prominently affecting the survival outcome and prognosis of patients. Univariate and multivariate COX regression analysis suggested that TNFRSF4 was an independent prognostic marker. Samples of high/low expression of TNFRSF4 were screened for differential genes, and then the WGCNA and LASSO COX constructed a 13-gene signature, excellently dividing samples into hign/low risk groups. Compared with the low-risk group, the overall survival (OS) of high-risk group was markedly lower, with P< 0.0001. By ROC curve analysis, the predictive ability of the 13-gene signature was further confirmed. Both the high/low TNFRSF4 expression and the high/low risk score were demonstrated to exert effects on the frequency of gene mutation in HCC. CONCLUSIONS: As an independent prognostic marker of HCC, TNFRSF4 was found simultaneously to affect the immune infiltration of cells and the frequency of gene mutations.

PscCYP716A1-Mediated Brassinolide Biosynthesis Increases Cadmium Tolerance and Enrichment in Poplar.

Cadmium (Cd), as one of the heavy metals with biological poisonousness, seriously suppresses plant growth and does harm to human health. Hence, phytoremediation was proposed to mitigate the negative effects from Cd and restore contaminated soil. However, the internal mechanisms of detoxification of Cd used in phytoremediation are not completely revealed. In this study, we cloned the cytochrome P450 gene PscCYP716A1 from hybrid poplar "Chuanxiang No. 1" and found that the PscCYP716A1 was transcriptionally upregulated by Cd stress and downregulated by the exogenous brassinolide (BR). Meanwhile, PscCYP716A1 significantly promoted the poplar growth and enhanced the Cd accumulation in poplar. Compared to wild-type poplars, overexpressed PscCYP716A1 lines produced higher levels of endogenous BR and showed a stronger tolerance to Cd, which revealed that PscCYP716A1 may reduce the oxidative stress damage induced by Cd stress through accelerating BR synthesis. In general, PscCYP716A1 has a potential superiority in regulating the plant's tolerance to Cd stress, which will provide a scientific basis and a new type of gene-modified poplar for Cd-pollution remediation.

Comparative In Vitro and In Vivo Hydroxylation Metabolization of Polychlorinated Biphenyl 101 in Laying Hens: A Pilot Study.

Polychlorinated biphenyls (PCBs) can be metabolized into hydroxylated PCBs (OH-PCBs) that exhibit greater toxicity than their parent compounds. In particular, 2,2',4,5,5'-pentachlorobiphenyl (PCB 101) is commonly found in chicken feeds and breeding environments, although information on the biotransformation of this PCB in chickens is lacking. In this study, the hydroxylation metabolization of PCB 101 was assessed based on in vitro trials with Sanhuang chicken liver microsomes and in vivo experiments with Hy-Line Brown hens. The para-substituted metabolite 4'-OH-PCB 101 is the predominant metabolite of PCB 101. 4'-OH-PCB 101 is preferentially retained in the chicken bloodstream and partly distributed into different tissues of laying hens. The blood-brain barrier can effectively prevent the OH-PCB from entering the brain, and the adipose tissue contains a relatively low residue concentration of the OH-PCB. The laying hen can deplete the OH-PCB via laying eggs and excrement. The ratio of 4'-OH-PCB 101/PCB 101 in egg yolk is about 1:2. These results first provide definite evidence for the previous hypothesis of the PCB 101 metabolism by chickens. They could assist in predicting the environmental fate of PCBs, and in the risk assessment of PCBs and OH-PCBs in chicken-based foodstuffs.

Genome-Wide Investigation of the PtrCHLP Family Reveals That PtrCHLP3 Actively Mediates Poplar Growth and Development by Regulating Photosynthesis.

Chlorophyll (Chl) plays a crucial role in plant photosynthesis. The geranylgeraniol reductase gene (CHLP) participates in the terminal hydrogenation of chlorophyll biosynthesis. Although there are many studies related to the genome-wide analysis of Populus trichocarpa, little research has been conducted on CHLP family genes, especially those concerning growth and photosynthesis. In this study, three CHLP genes were identified in Populus. The evolutionary tree indicated that the CHLP family genes were divided into six groups. Moreover, one pair of genes was derived from segmental duplications in Populus. Many elements related to growth were detected by cis-acting element analysis of the promoters of diverse PtrCHLPs. Furthermore, PtrCHLPs exhibit different tissue expression patterns. In addition, PtrCHLP3 is preferentially expressed in the leaves and plays an important role in regulating chlorophyll biosynthesis. Silencing of PtrCHLP3 in poplar resulted in a decrease in chlorophyll synthesis in plants, thus blocking electron transport during photosynthesis. Furthermore, inhibition of PtrCHLP3 expression in poplar can inhibit plant growth through the downregulation of photosynthesis. Ultimately, PtrCHLP3 formed a co-expression network with photosynthesis and chlorophyll biosynthesis-related genes, which synergistically affected the growth and photosynthesis of poplars. Thus, this study provides genetic resources for the improved breeding of fast-growing tree traits.

A WRKY transcription factor, PyWRKY75, enhanced cadmium accumulation and tolerance in poplar.

Cadmium (Cd) pollution has detrimental effects on the ecological environment and human health. Currently, phytoremediation is considered an environmentally friendly way to remediate Cd pollution. The application of transgenic plants to remediate soil pollution is a new technology that has emerged in recent years. In this study, PyWRKY75 was isolated and cloned from Populus yunnanensis, and the functionality of PyWRKY75 in woody plants (poplar) under Cd stress was verified. The increase in plant height of the OE-41 line (overexpression poplar) was 33.2% higher than that of the wild type (WT). Moreover, PyWRKY75 significantly promoted the absorption and accumulation of Cd in poplar, which increased by 51.32% in the OE-41 line when compared with the WT. The chlorophyll content of transgenic poplar leaves was higher than that of the WT, which reflected a protective mechanism of PyWRKY75. Other antioxidants, such as POD, SOD, CAT, APX, AsA, GSH and PCs, also made the transgenic poplars more tolerant to Cd, and they behaved differently in roots, stems and leaves. In general, PyWRKY75 played a potential role in regulating plant tolerance to Cd stress. This study provides a scientific basis and a new type of modified poplar for Cd pollution remediation.

Choroidal and Retinal Thickness and Axial Eye Elongation in Chinese Junior Students.

Purpose: To explore the associations between macular choroidal and retinal thickness and axial elongation in non-myopic and myopic junior students. Methods: In this school-based longitudinal observational study, axial length was measured by optical low-coherence reflectometry, and choroidal thickness and retinal thickness were measured by spectral-domain optical coherence tomography. Myopia was defined as non-cycloplegic objective spherical equivalent refraction ≤ -0.50 diopters. Structural equation modeling and multiple linear regression models were used to analyze the associations between baseline choroidal and retinal thickness with axial elongation. Results: Out of 1307 students examined at baseline in 2017, 1197 (91.58%) returned for follow-up examination in 2018, with a median age of 12.00 years (interquartile range [IQR], 1.00) and included 667 boys (55.72%). Within a 1-year period, the median axial elongation of right eyes was 230 µm (IQR, 180) in boys and 200 µm (IQR, 160) in girls (P = 0.032). The thinner temporal choroidal thickness was associated with greater 1-year axial elongation only in myopic students (ß, -0.20; 95% confidence interval [CI], -0.37, -0.03), the thinner temporal retinal thickness was associated with greater 1-year axial elongation in both non-myopic (ß, -2.67; 95% CI, -4.52, -0.82) and myopic (ß, -0.99; 95% CI, -1.68, -0.30) students, after adjustment for sex, age, and height. Subfoveal and nasal choroidal and retinal thickness were not significantly associated with axial elongation in either non-myopic or myopic students. Conclusions: A thinner temporal choroid at age 12 years may predict greater 1-year axial elongation in myopic students, and a thinner temporal retina may predict greater 1-year axial elongation in both non-myopic and myopic students. This finding may help to identify children at risk and control axial elongation with potential preventive strategies.

A dual immune signature of CD8+ T cells and MMP9 improves the survival of patients with hepatocellular carcinoma.

The 5-year survival of hepatocellular carcinoma (HCC) is difficult due to the high recurrence rate and metastasis. Tumor infiltrating immune cells (TICs) and immune-related genes (IRGs) bring hope to improve survival and treatment of HCC patients. However, there are problems in predicting immune signatures and identifying novel therapeutic targets. In the study, the CIBERSORT algorithm was used to evaluate 22 immune cell infiltration patterns in gene expression omnibus (GEO) and the cancer genome atlas (TCGA) data. Eight immune cells were found to have significant infiltration differences between the tumor and normal groups. The CD8+ T cells immune signature was constructed by least absolute shrinkage and selection operator (LASSO) algorithm. The high infiltration level of CD8+ T cells could significantly improve survival of patients. The weighted gene co-expression network analysis (WGCNA) algorithm identified MMP9 was closely related to the overall survival of HCC patients. K-M survival and tROC analysis confirmed that MMP9 had an excellent prognostic prediction. Cox regression showed that a dual immune signature of CD8+ T cells and MMP9 was independent survival factor in HCC. Therefore, a dual prognostic immune signature could improve the survival of patient and may provide a new strategy for the immunotherapy of HCC.

The Role of C-Reactive Protein and Fibrinogen in the Development of Intracerebral Hemorrhage: A Mendelian Randomization Study in European Population.

Background: The causal association of C-reactive protein (CRP) and fibrinogen on intracerebral hemorrhage (ICH) remains uncertain. We investigated the causal associations of CRP and fibrinogen with ICH using two-sample Mendelian randomization. Method: We used single-nucleotide polymorphisms associated with CRP and fibrinogen as instrumental variables. The summary data on ICH were obtained from the International Stroke Genetics Consortium (1,545 cases and 1,481 controls). Two-sample Mendelian randomization estimates were performed to assess with inverse-variance weighted and sensitive analyses methods including the weighted median, the penalized weighted median, pleiotropy residual sum and outlier (MR-PRESSO) approaches. MR-Egger regression was used to explore the pleiotropy. Results: The MR analyses indicated that genetically predicted CRP concentration was not associated with ICH, with an odds ratio (OR) of 1.263 (95% CI = 0.935-1.704, p = 0.127). Besides, genetically predicted fibrinogen concentration was not associated with an increased risk of ICH, with an OR of 0.879 (95% CI = 0.060-18.281; p = 0.933). No evidence of pleiotropic bias was detected by MR-Egger. The findings were overall robust in sensitivity analyses. Conclusions: Our findings did not support that CRP and fibrinogen are causally associated with the risk of ICH.

Analysis of Organochlorine Pesticide Residues in Various Vegetable Oils Collected in Chinese Markets.

Organochlorine pesticides (OCPs), chemicals frequently used in agriculture, are a group of highly toxic and persistent organic pollutants. This study assesses the distribution and congener profiles of residual OCPs in 11 types of vegetable oils collected from Chinese markets. All samples were extracted using the modified QuEChERS method prior to analysis by gas chromatography-triple quadrupole mass spectrometry. The sesame oil samples had the highest concentration of OCPs, within the range of 15.30-59.38 ng/g, whereas the peanut oil samples had the lowest OCP concentrations, within the range of 10.83-35.65 ng/g. The possible effect of the processing technology on the pesticide residues in these vegetable oils was also evaluated. It was found that the pressing method leaves more OCPs in vegetable oils than the aqueous extraction and cold-pressing, but the result for leaching was not obvious. In light of the obtained results, it was estimated that the average daily intake of different pesticides is between 0.01 and 2.20 ng/kg bw/day for urban and rural households. Hence, it can be affirmed that, given the amount of the concentration of OCPs detected in the vegetable oils collected from Chinese markets, there are no obvious health risks for urban and rural households by intake.

Sorption of DONs onto clay minerals in single-solute and multi-solute systems: Implications for DONs mobility in the vadose zone and leachability into groundwater.

Dissolved organic nitrogen (DON) with a mixture of various organic nitrogen (N) is recognized as an emerging groundwater contaminant. Investigating the behavior and mechanism of DON sorption onto clay minerals, which are key components of vadose zone media, is crucial to evaluating its leaching potential. Considering the interactions among multiple DON compounds (DONs) may influence their sorption behaviors, the sorption of three typical DONs (amino acid, protein and urea) to clay minerals in single-, binary- and ternary-solute systems were explored, respectively. In addition, a combination of multiple methods, including physiochemical characterization, Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD) and pH variation analysis, were used to provide insight into the governing mechanisms. Results indicated that the sorption kinetics and isotherms of single systems were well-fitted by pseudo-second-order and Freundlich isotherm models, respectively. The mechanisms involved in the sorption of DONs onto clay minerals varied with the sorption time. The dominant interactions included van der Waals forces, ligand exchange, and hydrogen bonding (H-bonding) in the initial phase of the sorption process, whereas electrostatic interactions were predominant in the later stage as H+ was released into the solution. In binary-solute systems, either cooperative or competitive sorption was observed depending on the co-solute combination. For instance, the sorption behaviors of amino acids and urea were simultaneously enhanced in the binary system because of the formation of highly charged complexes as new active sites. Proteins sorption, however, was inhibited by the coexistence of urea as a result of active site depletion and protein denaturation. In ternary-solute systems, the sorption of DONs was balanced by cooperative and competitive sorption processes. These findings elucidated the sorption behaviors of DONs onto clay minerals in multi-solute systems and contributed to the evaluation of the mobility of DONs in the vadose zone and their leachability into groundwater.

Prevalence and Associations of Fundus Tessellation Among Junior Students From Greater Beijing.

Purpose: To determine the prevalence of fundus tessellation and associations with ocular and systemic parameters among junior students from Greater Beijing. Methods: The school-based study included 1443 individuals with a mean age of 12.4 ± 0.5 years (range: 9-16 years). All participants underwent a comprehensive ophthalmic examination and an interview. Fundus tessellation, defined as variation in the visibility of large choroidal vessels, was differentiated into three grades. Results: The prevalence and degree of fundus tessellation were 688/1430 (48.1%; 95% confidence intervals [CI]: 45.5%, 50.7%) and 0.54 ± 0.61 (median, 0.00; range, 0-3), respectively. In multivariable regression analysis, a higher degree of fundus tessellation was associated with reduced subfoveal choroidal thickness (P < 0.001; beta, -0.02; odds ratio [OR], 0.98; 95% CI: 0.98, 0.99) and longer axial length (P < 0.001; beta, 0.23; OR, 1.25; 95% CI: 1.10, 1.43). Subfoveal choroidal thickness decreased from 299 ± 61 µm (95% CI: 293, 304) in eyes without fundus tessellation to 246 ± 57 µm (95% CI: 241, 251), 197 ± 43 µm (95% CI: 187, 207), and 131 ± 30 µm (95% CI: 93, 168) in eyes with grade 1, 2, and 3 fundus tessellation, respectively. A higher degree of peripapillary fundus tessellation was associated with reduced subfoveal choroidal thickness (P < 0.001; beta, -0.02; OR, 0.98; 95% CI: 0.98, 0.99) and younger age at myopia onset (P = 0.008; beta, 0.41; OR, 1.51; 95% CI: 1.11, 2.04). Conclusions: The prevalence of fundus tessellation is relatively high in Chinese teenagers. As in adults, the degree of fundus tessellation is a surrogate for choroidal thickness in teenagers. Marked fundus tessellation indicates a leptochoroid and is associated with earlier myopia onset.

Recovery Performance of Ge-Doped Vertical GaN Schottky Barrier Diodes.

Vertical GaN Schottky barrier diodes (SBDs) were fabricated on Ge-doped free-standing GaN substrates. The crystal quality of the SBDs was characterized by cathode luminescence measurement, and the dislocation density was determined to be ~ 1.3 × 106 cm- 2. With the electrical performance measurements conducted, the SBDs show a low turn-on voltage Von (0.70~0.78 V) and high current Ion/Ioff ratio (9.9 × 107~1.3 × 1010). The reverse recovery characteristics were investigated. The reverse recovery time was obtained to be 15.8, 16.2, 18.1, 21.22, and 24.5 ns for the 100-, 200-, 300-, 400-, and 500-µm-diameter SBDs, respectively. Meanwhile, the reverse recovery time and reverse recovery charge both show a significant positive correlation with the electrode area.

Changes in Proteome and Protein Phosphorylation Reveal the Protective Roles of Exogenous Nitrogen in Alleviating Cadmium Toxicity in Poplar Plants.

Phytoremediation soil polluted by cadmium has drawn worldwide attention. However, how to improve the efficiency of plant remediation of cadmium contaminated soil remains unknown. Previous studies showed that nitrogen (N) significantly enhances cadmium uptake and accumulation in poplar plants. In order to explore the important role of nitrogen in plants' responses to cadmium stress, this study investigates the poplar proteome and phosphoproteome difference between Cd stress and Cd + N treatment. In total, 6573 proteins were identified, and 5838 of them were quantified. With a fold-change threshold of > 1.3, and a p-value < 0.05, 375 and 108 proteins were up- and down-regulated by Cd stress when compared to the control, respectively. Compared to the Cd stress group, 42 and 89 proteins were up- and down-regulated by Cd + N treatment, respectively. Moreover, 522 and 127 proteins were up- and down-regulated by Cd + N treatment compared to the CK group. In addition, 1471 phosphosites in 721 proteins were identified. Based on a fold-change threshold of > 1.2, and a p-value < 0.05, the Cd stress up-regulated eight proteins containing eight phosphosites, and down-regulated 58 proteins containing 69 phosphosites, whereas N + Cd treatment up-regulated 86 proteins containing 95 phosphosites, and down-regulated 17 proteins containing 17 phosphosites, when compared to Cd stress alone. N + Cd treatment up-regulated 60 proteins containing 74 phosphosites and down-regulated 37 proteins containing 42 phosphosites, when compared to the control. Several putative responses to stress proteins, as well as transcriptional and translational regulation factors, were up-regulated by the addition of exogenous nitrogen following Cd stress. Especially, heat shock protein 70 (HSP70), 14-3-3 protein, peroxidase (POD), zinc finger protein (ZFP), ABC transporter protein, eukaryotic translation initiation factor (elF) and splicing factor 3 B subunit 1-like (SF3BI) were up-regulated by Cd + N treatment at both the proteome and the phosphoproteome levels. Combing the proteomic data and phosphoproteomics data, the mechanism by which exogenous nitrogen can alleviate cadmium toxicity in poplar plants was explained at the molecular level. The results of this study will establish the solid molecular foundation of the phytoremediation method to improve cadmium-contaminated soil.

A Review of Fast Bubble-Driven Micromotors Powered by Biocompatible Fuel: Low-Concentration Fuel, Bioactive Fluid and Enzyme.

Micromotors are extensively applied in various fields, including cell separation, drug delivery and environmental protection. Micromotors with high speed and good biocompatibility are highly desirable. Bubble-driven micromotors, propelled by the recoil effect of bubbles ejection, show good performance of motility. The toxicity of concentrated hydrogen peroxide hampers their practical applications in many fields, especially biomedical ones. In this paper, the latest progress was reviewed in terms of constructing fast, bubble-driven micromotors which use biocompatible fuels, including low-concentration fuels, bioactive fluids, and enzymes. The geometry of spherical and tubular micromotors could be optimized to acquire good motility using a low-concentration fuel. Moreover, magnesium- and aluminum-incorporated micromotors move rapidly in water if the passivation layer is cleared in the reaction process. Metal micromotors demonstrate perfect motility in native acid without any external chemical fuel. Several kinds of enzymes, including catalase, glucose oxidase, and ureases were investigated to serve as an alternative to conventional catalysts. They can propel micromotors in dilute peroxide or in the absence of peroxide.

Soluble organic nitrogen cycling in soils after application of chemical/organic amendments and groundwater pollution implications.

Nitrogen (N) fertilizers have been extensively used to maintain soil fertility in intensively agricultural soils, creating serious environmental pollution. In this study, a 70-day incubation experiment was conducted to investigate the effects of different N fertilizers (urea, manure, straw) on N mineralization, soluble organic nitrogen (SON) dynamics and its leaching potential in typical agricultural soils of the Shandong Peninsula. The results showed that the addition of N fertilizers affected the SON pools and soil N mineralization in different ways owing to their various properties and interaction with soils. When comparing treatments, urea application was found to decrease SON content, whereas manure and straw addition increased the SON content after long-term incubation. Considering that SON content depended on a complicated formation process and consumption process, no direct link between SON content and N mineralization capacity was observed in different treatments. Additionally, we analyzed free amino acids (FAAs) in SON and found that FAA content was negatively correlated with N mineralization, except for the straw treatment. This suggested that FAAs were important substrates of N mineralization in soils. In addition, the composition of SON was determined by 3-dimensional excitation-emission matrix and ultraviolet-visible absorbance spectrophotometer after long-term incubation. The PIII+V/PI+II+IV ratio, SUVA254, and A253/A203 ratio decreased after fertilizer application. This indicated that fertilizer addition decreased the SON humification degree and increased SON leaching. Therefore, SON should be taken into account when optimizing fertilization management and evaluating the risk of N leaching in groundwater systems.

[Effects of Various Combinations of Fertilizer, Soil Moisture, and Temperature on Nitrogen Mineralization and Soluble Organic Nitrogen in Agricultural Soil].

An 84-day laboratory incubation experiment was conducted to investigate the effects of different fertilizers (urea; manure), moisture conditions (60%, 75% and 90% water holding capacity) and temperatures (15, 25 and 35℃) on nitrogen mineralization. The experiment included 3 treatments:①CK, unfertilized control; ② Ur, adding urea at N 120 mg·kg-1; 3 UM, adding urea and manure (equal to adding N 120 mg·kg-1). Total inorganic nitrogen and soluble organic nitrogen (SON) were determined at different times throughout the experiment. The results showed that soil temperature and fertilization type had significant impacts on the net mineralization rates, cumulative mineralization, and the potentially mineralizable nitrogen (N0) (P<0.01). In addition, the soil net N mineralization rates and cumulative mineralization significantly (P<0.05) increased by 1.46-8.17 and 2.00-8.15 times, respectively, when fertilizers were added into soils. The soil net N mineralization rates and cumulative mineralization increased with the increase of temperature. Compared with CK treatment, Ur and UM treatments could significantly increase the content of soil soluble organic nitrogen(SON). There was a significant negative correlation between the content of SON and cumulative mineralization. It indicated that SON was involved in soil nitrogen mineralization as a non-negligible component. Increasing the temperature could significantly increase the mineralization rate and mineralization intensity of SON in soil, but the water content had no significant influence on the SON of the soils. Moreover, the authors found that fertilization treatment worked significantly in decreasing the Q10 value for soil N mineralization compared with CK treatment. Further, the Q10 value was significantly lowest in UM treatment(Q10=1.01). The results showed that the application of organic manure significantly reduced the sensitivity of the rate of nitrogen mineralization to temperature changes, which was beneficial in slowing down the release rate of mineral nitrogen under high temperatures and improving the nitrogen utilization efficiency of crops.