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Plant diversity may respond differently in terms of whether it can drive plant invasions in freshwater ecosystem. Linkages and interactions between diversity and invasibility have not been clearly resolved, and it is unclear how nutrient enrichment (e.g., eutrophication) will affect this relationship. As a key predictor of plant growth, the ability of functional traits to mediate trade-offs in the diversity-invasibility relationship is unknown. Here, we conducted a series of experiments to determine the role of exotic plant functional traits in the diversity-invasibility relationship of submerged macrophyte communities under eutrophication. We selected common native and exotic submerged macrophytes in the subtropics to construct different diverse submerged macrophyte communities to simulate invasion. Meanwhile, to test the adaptability and importance of functional traits, we experimentally verified the differences in functional traits between exotic and native species. Our results showed a positive correlation between native plant diversity and community invasibility. Moreover, the invader's performance was predominantly determined by functional traits of exotic species, such as plant biomass and tissue nutrients, which were significantly altered by species diversity. Furthermore, our results suggested that functional traits contribute significantly more to the invasiveness of exotic submerged macrophytes than the other factors to which they are subjected. Plant functional traits can mediate the diversity-invasibility relationship because of the higher intrinsic dominance of exotic submerged macrophyte species. In summary, our study revealed diversity-invasibility relationship in submerged macrophyte communities and highlighted functional traits as key drivers of invasion of high-risk exotic submerged macrophyte species. Although previous studies have elucidated the importance of functional trait studies for plant invasions, our study provides the only current evidence demonstrating the important role of invaders' functional traits in mediating the diversity-invasibility relationship. This novel perspective offers valuable insights into the management and control of invasive aquatic plants.
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Biodiversidad , Eutrofización , Agua Dulce , Especies Introducidas , Plantas , EcosistemaRESUMEN
Nitrogen removal is essential for restoring eutrophic lakes. Microorganisms and aquatic plants in lakes are both crucial for removing excess nitrogen. However, microplastic (MP) pollution and the invasion of exotic aquatic plants have become increasingly serious in lake ecosystems due to human activity and plant-dominant traits. This field mesocosm study explored how the diversity of invasive submerged macrophytes affects denitrification (DNF), anammox (ANA), and dissimilatory nitrate reduction to ammonium (DNRA) in lake sediments with varying MPs. Results showed that invasive macrophytes suppressed DNF rates, but DNRA and ANA were less sensitive than DNF to the diversity of invasive species. Sediment MPs increased the biomass of invasive species more than native species, but did not affect microbial processes. The effects of MPs on nitrate dissimilatory reduction were process-specific. MPs increased DNF rates and the competitive advantage of DNF over DNRA by changing the sediment environment. The decoupling of DNF and ANA was also observed, with increased DNF rates and decreased ANA rates. The study findings suggested new insights into how the invasion of exotic submerged macrophytes affects the sediment nitrogen cycle complex environments.
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Sedimentos Geológicos , Especies Introducidas , Lagos , Microplásticos , Nitratos , Plantas , Sedimentos Geológicos/microbiología , Nitratos/metabolismo , Plantas/metabolismo , Microplásticos/metabolismo , Lagos/microbiología , Contaminantes Químicos del Agua/metabolismo , Oxidación-Reducción , Biodiversidad , DesnitrificaciónRESUMEN
Purpose: This study investigates how challenge-hindrance stressors influence employability through the energy-motivation mechanism and explores the moderating role of pay satisfaction and perceived career opportunity based on the JD-R model. Methods: Three-wave time-lagged longitudinal data of 206 employees are analyzed using latent structural equation modelling. Results: First, challenge stressors have an indirect positive effect on employability, mainly through intrinsic motivation, while hindrance stressors have an indirect negative effect on employability, mainly through emotional exhaustion. Second, perceived career opportunity strengthens the positive effect of challenge stressors on intrinsic motivation, which further promotes employability. Third, pay satisfaction alleviates the negative effect of hindrance stressors on emotional exhaustion, which, in turn, inhibits the decline in employability. Conclusion: The paper clarifies the specific mediating effects of the energy and motivation mechanisms in the association between challenge-hindrance stressors and employability and the moderating effects of pay satisfaction and perceived career opportunity, thus extending studies on the challenge-hindrance stressors to career field and filling the gap in the knowledge of the boundary conditions of the energy-motivation mechanism.
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Currently little is known about the adsorption behaviors of metalloids on microplastics (MPs) and their complex toxic effects on aquatic plants. Herein, we investigated the adsorption behaviors of arsenic (As(III) and As(V)) on three types of MPs (polystyrene, polyvinyl chloride, and polyethylene) with four different particle sizes (100, 10, 1, and 0.1 µm). Compared with the short-term exposure experiment, co-toxicity of polystyrene nanoplastics (PS-NPs) and As on two submerged macrophytes (Vallisneria denseserrulata and Potamogeton crispus) were explored through two relatively longer 14-day-cultivation experiments in summer and spring, respectively. The adsorption results showed that As entered the internal surface adsorption site of MPs at 24 h and fully combined to reach equilibrium. The adsorption capacity also enhanced with the increase of MPs concentrations, which generated more adsorption sites for binding with MPs. The presence of PS-NPs increased the absorption of As on macrophytes by 36.2-47.2%. More serious damage of leaf structure by combined PS-NPs and As was observed by transmission electron microscope. The larger harms by the co-toxicity of MPs and As were also reflected by the changes in physiochemical characteristics (e.g. photosynthesis) and the enhancement of oxidative damage of macrophytes. This work provides a clear theoretical basis for the behavior of PS-NPs as carrier with other contaminants on submerged macrophytes, and clearly evaluates the co-toxicity of NPs and metalloids in complex aquatic environments.
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Arsénico , Contaminantes Químicos del Agua , Adsorción , Arsénico/toxicidad , Microplásticos , Plásticos , Poliestirenos/toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidadRESUMEN
Background: Colorectal cancer (CRC) is a leading cause of cancer-related death. CRC patients have a poor prognosis due to tumor metastasis and recurrence. Fibroblast growth factor 12 (FGF12), a member of the FGF family, is highly expressed in several cancers. However, little is known about the roles of FGF12 in CRC progression. Methods: The overall survival (OS) of CRC patients was detected via Kaplan-Meier analysis. The FGF12 expression in both CRC tissues and cells was analyzed by qRT-PCR, immunohistochemistry (IHC), and western blotting (WB). LoVo and SW480 cells were transfected with shFGF12 lentivirus to silence FGF12. In vivo and in vitro experiments were performed to explore the FGF12 functions in CRC, including CCK-8, Edu, flow cytometry, Transwell, EMT, cancer stemness, and tumor xenograft experiments. Results: FGF12 was upregulated in both CRC cells and tissues. High expression of FGF12 indicated a shorter OS in CRC patients. FGF12 knockdown inhibited the proliferation, invasion, stemness, and EMT of CRC cells. FGF12 knockdown promoted CRC cell apoptosis in vitro. 740 Y-P (a PI3K/AKT pathway activator) restored the proliferation, stemness, invasion, and EMT in FGF12-deficient cells and reversed LoVo cell apoptosis induced by FGF12 depletion. Depletion of FGF12 inhibited tumor growth, EMT, cancer stemness, and PI3K/AKT pathway in a xenograft mouse model. Conclusions: FGF12 predicts bad clinical outcome and modulates the viability, stemness, and motility of CRC cells. Our study may provide a new insight for the diagnosis and treatment of CRC.
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Neoplasias Colorrectales , Proteínas Proto-Oncogénicas c-akt , Animales , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Neoplasias Colorrectales/patología , Factores de Crecimiento de Fibroblastos/genética , Factores de Crecimiento de Fibroblastos/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismoRESUMEN
Microplastic pollution has become ubiquitous due to industrialization and wide use of plastic products. The continuous discharge of microplastics into aquatic ecosystems, combined with different toxic chemicals can create serious environmental pollution. Lead is an extremely toxic metal which can strongly adsorb to microplastics, however, little is known about their combined toxicity on submerged macrophytes. To test our hypothesis that microplastic can aggravate lead toxicity on submerged macrophytes, we designed a five-day hydroponic experiment to explore the toxic effects of microplastic and lead alone, and in combination, on Potamogeton crispus and Vallisneria denseserrulata. Photosynthetic pigment, chlorophyll fluorescence (Fv/Fm and ETRmax), soluble sugar, protein and malondialdehyde (MDA) declined with increasing lead concentration alone and in the combined treatment. In both submerged macrophytes, the level of superoxide dismutase (SOD) and lead bioaccumulation increased with increasing lead concentration. However, microplastic aggravated lead toxicity on chlorophyll a and SOD activity in P. crispus only under the highest lead concentration. In conclusion, lead alone and combined exposure caused a series of toxic effects on physio-biochemical traits of submerged macrophytes that appeared to be synergistic and species-specific. Our comprehensive results have important implications for appropriate management of microplastics and lead alone, or in combination, for submerged macrophytes.
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Microplásticos , Plásticos , Clorofila A , Ecosistema , Plomo/toxicidad , Plásticos/toxicidadRESUMEN
Although studies have indicated the influences of job crafting on contemporary employees' working outcomes, the path from job crafting to turnover intention is still unexplored in depth. Drawing on goal facilitation theory, we delineate how job crafting relates to turnover intention through organizational instrumentality and is conditioned by inclusive leadership. We collected data from 218 employees from Chinese high-tech companies at two different time points by submitting survey questionnaires. The results indicated that employees' job crafting relates positively to their perception of organizational instrumentality and further results in decreased turnover intention. We also found that inclusive leadership not only positively moderates the path from job crafting to organizational instrumentality but also positively moderates the whole mediational relationship. Moreover, job crafting relates positively and directly to turnover intention-i.e., the more employees craft their jobs, the more likely they leave their organizations when we control the roles of organizational instrumentality and inclusive leadership. Finally, the theoretical and practical implications are also discussed.
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The efficacy of chemotherapy for colon cancer is limited due to the development of chemoresistance. MicroRNA (miR)-188-5p is downregulated in various types of cancer. The aim of the present study was to explore the molecular role of miR-188 in oxaliplatin (OXA) resistance. An OXA-resistant colon cancer cell line, SW480/OXA, was used to examine the effects of miR-188-5p on the sensitivity of colon cancer cells to OXA. The target of miR-188-5p was identified using a luciferase assay. Cell cycle distribution was also assessed using flow cytometry. The measurement of p21 protein expression, Hoechst 33342 staining and Annexin V/propidium iodide staining was used to evaluate apoptosis. The expression of miR-188-5p significantly increased in SW480/OXA compared with wild-type SW480 cells. The luciferase assay demonstrated that miR-188-5p inhibited Ras GTPase-activating protein 1 (RASA1; also known as p120/RasGAP) luciferase activity by binding to the 3'-untranslated region of RASA1 mRNA, suggesting that miR-188-5p could target RASA1. In addition, miR-188-5p downregulation or RASA1 overexpression promoted the chemosensitivity of SW480/OXA, as evidenced by increased apoptosis and G1/S cell cycle arrest. Moreover, RASA1 silencing abrogated the increase in cell apoptosis induced by the miR-188-5p inhibitor. The findings of the present study suggested that miR-188-5p could enhance colon cancer cell chemosensitivity by promoting the expression of RASA1.
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Adaptivity and adaptability are two key elements representing one's "willingness" and "ability," respectively, in the career construction theory (CCT) framework. On the basis of CCT and complemented by the visual of resources in the conservation of resources theory, this study combines career issues and performance and examines the joint effect of adaptivity and adaptability on career self-management which will lead to improved performance. Using a sample of Chinese employees (N = 232), the study first examines the mediating role that career self-management plays between career adaptability and performance and then tests the moderating role of proactive personality. Results show career adaptability positively predicts performance, with this relationship partially mediated by career self-management. The positive effect of career adaptability on career self-management is stronger among those who are more proactive than less proactive. Further, the indirect effect of career adaptability on performance is stronger among proactive employees than those with lower levels of proactive personality. These findings provide implications for both theories and practices.
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The widespread use of whole-body small animal in vivo imaging in preclinical research has proposed the new demands on imaging processing and analysis. Micro-CT provides detailed anatomical structural information for continuous detection and different individual comparison, but the body deformation happened during different data acquisition needs sophisticated registration. In this paper, we propose a hybrid method for registering micro-CT mice images, which combines the strengths of point-based and intensity-based registration methods. Point-based non-rigid method using thin-plate spline robust point matching algorithm is utilized to acquire a coarse registration. And then intensity-based non-rigid method using normalized mutual information, Halton sampling and adaptive stochastic gradient descent optimization is used to acquire precise registration. Two accuracy metrics, Dice coefficient and average surface distance are used to do the quantitative evaluation. With the intra- and intersubject micro-CT mice images registration assessment, the hybrid method has been proven capable of excellent performance on micro-CT mice images registration.
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Procesamiento de Imagen Asistido por Computador/métodos , Imagen de Cuerpo Entero/métodos , Microtomografía por Rayos X/métodos , Animales , RatonesRESUMEN
There is evidence that stearoyl-CoA desaturase (SCD) is a key enzyme for lipid metabolism. Changes in enzyme activity that depends on SCD gene polymorphism and regulation could cause variations of fatty acid composition of meat and milk. We investigated genetic variability in caprine SCD, analyzing 335 animals belonging to three goat breeds by single-strand conformation polymorphism and DNA sequencing. Six single nucleotide polymorphism were identified, in intron 3 (585T-->A and 601A-->G; Ref. AF422168), intron 4 (719T-->A; AF422169), and exon 6 (690 A-->G, 718 C-->G, and 802 A-->C; AF422171). The less polymorphic SNP 601A-->G displayed variability only in Xuhuai and Boer breeds. Across breeds, the average frequency for the least frequent alleles ranged from 0.1158 to 0.2532. The three SNPs in exon 6 resulted in variations of amino acids 313 tyr --> cys, 322 phe --> leu, and 350 arg --> ser. The allelic distribution in exon 6 of Xuhuai was significantly different from Boer and Haimen.
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Cabras/genética , Polimorfismo de Nucleótido Simple , Estearoil-CoA Desaturasa/genética , Animales , Ácidos Grasos/metabolismo , Frecuencia de los Genes , Marcadores Genéticos/genética , Cabras/anatomía & histología , Cabras/metabolismo , Carne , Polimorfismo Conformacional Retorcido-SimpleRESUMEN
Prolactin (PRL) plays a crucial role in the initiation and maintenance of lactation in mammals. In this study, seven PCR fragments representing most important functional domains of PRL gene were screened for single nucleotide polymorphisms (SNPs) in Chinese Holsteins by single-strand conformation polymorphisms and amplicons sequencing, and their genetic effects on milk production traits were evaluated. A total of four SNPs, including two in the promoter (-1043A>G and -402A>G), one in intron 1 (+2723C>T) and one in exon 4 (+8398G>A) were identified in PRL gene. Statistical results showed significant associations between the promoter genotypes and the milk performance traits in Chinese Holsteins. Cows with genotype P1-GG showed higher milk yields (P < 0.01), while cows with genotype P1-AA showed higher fat contents (P < 0.01). Haplotype analysis of two SNPs in promoter region revealed that the Hap(AG) was significantly associated with increased milk yields and Hap(AA) was associated with increased fat contents (P < 0.01). This is the second study reporting SNPs in the 5'-regulatory region of PRL gene, which interfere with milk production traits.
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Bovinos/genética , Lactancia/genética , Leche/metabolismo , Polimorfismo de Nucleótido Simple/genética , Prolactina/genética , Carácter Cuantitativo Heredable , Animales , China , Femenino , Frecuencia de los Genes/genética , Sitios Genéticos/genética , Haplotipos/genética , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Regiones Promotoras Genéticas/genéticaRESUMEN
Bone morphogenetic protein 4 (BMP4) plays a crucial role in growth and development of mammals, especially for bone growth. The aim of the present study was to assess the association of polymorphism in BMP4 gene with growth traits in three goat breeds. In this study, on the basis of PCR-SSCP and DNA sequencing methods, two new silent mutation sites of A1986G and G2203A were identified in the intron 2, and one novel microsatellite of dinucleotide-repeated (CA) sequence was in the 3' flanking region. Associations between growth traits and BMP4 gene polymorphism were investigated, and significant statistical association results were found in body height, chest circumference and trunk index (P < 0.05). The result strongly suggested that the microsatellite located in BMP4 gene might be in linkage with the two new SNPs. Further investigations are required for detecting the polymorphism of this gene in a broad variety of goat breeds and populations.
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Proteína Morfogenética Ósea 4/genética , Cabras/crecimiento & desarrollo , Polimorfismo Genético , Región de Flanqueo 3' , Sustitución de Aminoácidos , Animales , Repeticiones de Dinucleótido , Cabras/genética , Crecimiento/genética , Repeticiones de MicrosatéliteRESUMEN
Single nucleotide polymorphisms (SNPs) of hircine myf-5, myf-6 genes and 5'flanking region of the myoD gene (myoD 5') were analyzed by PCR-SSCP in Boer goat and Xuhuai white goat. Three genotypes were found at the myf-5 locus of Xuhuai white goat, denoted AA, AB and BB, while all of Boer goats were of AA genotype. Only AA and AB genotypes were found at myf-6 and myoD 5' loci. The effects of genotypes of myf-5, myf-6 and myoD 5'flanking region loci on body measurement traits were estimated. The results showed that genotypes at the myf-5 locus were significantly associated with hucklebone width and hucklebone width index in Xuhuai white goat (P<0.05). Genotypes at the myf-6 locus were significantly associated with withers heights and hucklebone width index in Boer goat (P<0.05), but no significant associations were found for any traits in Xuhuai white goat. The myoD 5' locus was not significantly associated with any traits in both types of goat.