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1.
Nature ; 631(8019): 67-72, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38839970

RESUMEN

Since the demonstration of p-type gallium nitride (GaN) through doping with substitutional magnesium (Mg) atoms1,2, rapid and comprehensive developments, such as blue light-emitting diodes, have considerably shaped our modern lives and contributed to a more carbon-neutral society3-5. However, the details of the interplay between GaN and Mg have remained largely unknown6-11. Here we observe that Mg-intercalated GaN superlattices can form spontaneously by annealing a metallic Mg film on GaN at atmospheric pressure. To our knowledge, this marks the first instance of a two-dimensional metal intercalated into a bulk semiconductor, with each Mg monolayer being intricately inserted between several monolayers of hexagonal GaN. Characterized as an interstitial intercalation, this process induces substantial uniaxial compressive strain perpendicular to the interstitial layers. Consequently, the GaN layers in the Mg-intercalated GaN superlattices exhibit an exceptional elastic strain exceeding -10% (equivalent to a stress of more than 20 GPa), among the highest recorded for thin-film materials12. The strain alters the electronic band structure and greatly enhances hole transport along the compression direction. Furthermore, the Mg sheets induce a unique periodic transition in GaN polarity, generating polarization-field-induced net charges. These characteristics offer fresh insights into semiconductor doping and conductivity enhancement, as well as into elastic strain engineering of nanomaterials and metal-semiconductor superlattices13.

2.
BMC Genomics ; 25(1): 429, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38689208

RESUMEN

BACKGROUND: Expression quantitative trait loci (eQTL) studies aim to understand the influence of genetic variants on gene expression. The colocalization of eQTL mapping and GWAS strategy could help identify essential candidate genes and causal DNA variants vital to complex traits in human and many farm animals. However, eQTL mapping has not been conducted in ducks. It is desirable to know whether eQTLs within GWAS signals contributed to duck economic traits. RESULTS: In this study, we conducted an eQTL analysis using publicly available RNA sequencing data from 820 samples, focusing on liver, muscle, blood, adipose, ovary, spleen, and lung tissues. We identified 113,374 cis-eQTLs for 12,266 genes, a substantial fraction 39.1% of which were discovered in at least two tissues. The cis-eQTLs of blood were less conserved across tissues, while cis-eQTLs from any tissue exhibit a strong sharing pattern to liver tissue. Colocalization between cis-eQTLs and genome-wide association studies (GWAS) of 50 traits uncovered new associations between gene expression and potential loci influencing growth and carcass traits. SRSF4, GSS, and IGF2BP1 in liver, NDUFC2 in muscle, ELF3 in adipose, and RUNDC1 in blood could serve as the candidate genes for duck growth and carcass traits. CONCLUSIONS: Our findings highlight substantial differences in genetic regulation of gene expression across duck primary tissues, shedding light on potential mechanisms through which candidate genes may impact growth and carcass traits. Furthermore, this availability of eQTL data offers a valuable resource for deciphering further genetic association signals that may arise from ongoing extensive endeavors aimed at enhancing duck production traits.


Asunto(s)
Patos , Estudio de Asociación del Genoma Completo , Sitios de Carácter Cuantitativo , Animales , Patos/genética , Patos/crecimiento & desarrollo , Patos/metabolismo , Fenotipo , Especificidad de Órganos/genética , Polimorfismo de Nucleótido Simple
3.
Nano Lett ; 23(18): 8585-8592, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37669044

RESUMEN

Single-atom nanozymes (SAzymes) open new possibilities for the development of artificial enzymes that have catalytic activity comparable to that of natural peroxidase (POD). So far, most efforts have focused on the structural modulation of the Fe-N4 moiety to mimic the metalloprotein heme center. However, non-heme-iron POD with much higher activity, for example, HppE, has not been mimicked successfully due to its structural complexity. Herein, carbon dots (CDs)-supported SAzymes with twisted, nonplanar Fe-O3N2 active sites, highly similar to the non-heme iron center of HppE, was synthesized by exploiting disordered and subnanoscale domains in CDs. The Fe-CDs exhibit an excellent POD activity of 750 units/mg, surpassing the values of conventional SAzymes with planar Fe-N4. We further fabricated an activatable Fe-CDs-based therapeutic agent with near-infrared enhanced POD activity, a photothermal effect, and tumor-targeting ability. Our results represent a big step in the design of high-performance SAzymes and provide guidance for future applications for synergistic tumor therapy.

4.
Genome Res ; 30(5): 790-801, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32424068

RESUMEN

By uniformly analyzing 723 RNA-seq data from 91 tissues and cell types, we built a comprehensive gene atlas and studied tissue specificity of genes in cattle. We demonstrated that tissue-specific genes significantly reflected the tissue-relevant biology, showing distinct promoter methylation and evolution patterns (e.g., brain-specific genes evolve slowest, whereas testis-specific genes evolve fastest). Through integrative analyses of those tissue-specific genes with large-scale genome-wide association studies, we detected relevant tissues/cell types and candidate genes for 45 economically important traits in cattle, including blood/immune system (e.g., CCDC88C) for male fertility, brain (e.g., TRIM46 and RAB6A) for milk production, and multiple growth-related tissues (e.g., FGF6 and CCND2) for body conformation. We validated these findings by using epigenomic data across major somatic tissues and sperm. Collectively, our findings provided novel insights into the genetic and biological mechanisms underlying complex traits in cattle, and our transcriptome atlas can serve as a primary source for biological interpretation, functional validation, studies of adaptive evolution, and genomic improvement in livestock.


Asunto(s)
Bovinos/genética , Transcriptoma , Animales , Bovinos/crecimiento & desarrollo , Bovinos/fisiología , Metilación de ADN , Femenino , Genes , Leche , Especificidad de Órganos , RNA-Seq , Reproducción
5.
Small ; : e2308531, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-38047546

RESUMEN

Conventional triboelectric nanogenerators (TENGs) face challenges pertaining to low output current density at low working frequencies and high internal impedance. While strategies, such as surface modification to enhance surface charge density, permittivity regulation of materials, and circuit management, have partially mitigated these issues. However, they have also resulted in increased complexity in the fabrication process. Therefore, there is an urgent demand for a universal and simplified approach to address these challenges. To fulfill this need, this work presents a free-standing electrode and fixed surface tiny electrode implemented triboelectric nanogenerator (FFI-TENG). It is fabricated by a straightforward yet effective method: introducing a tiny electrode onto the surface of the tribo-negative material. This approach yields substantial enhancements in performance, notably a more than tenfold increase in output current density, a reduction in effective working frequencies, and a decrease in matching resistance as compared to vertical contact-separation TENGs (CS-TENGs) or single-electrode TENGs (SE-TENGs). Simultaneously, a comprehensive examination and proposition regarding the operational mechanism of FFI-TENG, highlighting its extensive applicability are also offered. Significantly, FFI-TENG excels in mechanical energy harvesting even under ultra-low working frequencies (0.1 Hz), outperforming similar contact-separation models. This innovation positions it as a practical and efficient solution for the development of low-entropy energy harvesters.

6.
Genomics ; 114(4): 110406, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35709924

RESUMEN

Fat deposition is a complex economic trait regulated by polygenic genetic basis and environmental factors. Therefore, integrating multi-omics data to uncover its internal regulatory mechanism has attracted extensive attention. Here, we performed genomics and transcriptomics analysis to detect candidates affecting subcutaneous fat (SCF) deposition in beef cattle. The association of 770K SNPs with the backfat thickness captured nine significant SNPs within or near 11 genes. Additionally, 13 overlapping genes regarding fat deposition were determined via the analysis of differentially expressed genes and weighted gene co-expression network analysis (WGCNA). We then calculated the correlations of these genes with BFT and constructed their interaction network. Finally, seven biomarkers including ACACA, SCD, FASN, ACOX1, ELOVL5, HACD2, and HSD17B12 were screened. Notably, ACACA, identified by the integration of genomics and transcriptomics, was more likely to exert profound effects on SCF deposition. These findings provided novel insights into the regulation mechanism underlying bovine fat accumulation.


Asunto(s)
Grasa Subcutánea , Transcriptoma , Animales , Bovinos/genética , Perfilación de la Expresión Génica , Genómica , Polimorfismo de Nucleótido Simple
7.
Opt Lett ; 47(9): 2250-2253, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35486772

RESUMEN

This Letter describes the impact of shape on micro light-emitting diodes (µLEDs), analyzing 400 µm2 area µLEDs with various mesa shapes (circular, square, and stripes). Appropriate external quantum efficiency (EQE) can yield internal quantum efficiency (IQE) which decreases with increasing peripheral length of the mesas. However, light extraction efficiency (ηe) increased with increasing mesa periphery. We introduce analysis of Jpeak (the current at peak EQE) since it is proportional to the non-radiative recombination. Etching the sidewalls using tetramethylammonium hydroxide (TMAH) increased the peak EQE and decreased the sidewall dependency of Jpeak. Quantitatively, the TMAH etching reduced non-radiative surface recombination by a factor of four. Hence, shrinking µLEDs needs an understanding of the relationship between non-radiative recombination and ηe, where analyzing Jpeak can offer new insights.

8.
BMC Gastroenterol ; 22(1): 26, 2022 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-35045814

RESUMEN

BACKGROUND: Sarcopenia is an age-related syndrome that may have negative impact on surgical outcomes and long-term survival of patients with gastric cancer. Serum creatinine/cystatin C (Cr/CysC) ratio has attracted attention as a surrogate marker for sarcopenia but has not been adequately studied in patients with gastric cancer. The purpose of this study was to investigate the validity of serum Cr/CysC ratio as a predictor of sarcopenia, evaluate a statistical cut-off value, and assess the relationship between Cr/CysC ratio and prognosis of patients with gastric cancer. METHODS: We retrospectively studied 327 patients who underwent surgery for gastric cancer from June 2009 to October 2021. The skeletal muscle mass index was calculated using computed tomography (CT). We determined the relevance of serum Cr/CysC ratio as a surrogate maker for sarcopenia by comparing it with various biomarkers. The Concordance index (C-index) was calculted to measure whether the Cr/CysC ratio can prognosis of patients with gastric cancer. RESULTS: Serum Cr/CysC was significantly correlated with with Skeletal Muscle Index (SMI) (r = 0.221, p < 0.001) and Skeletal Muscle Area (SMA) (r = 0.258, p < 0.001). The area under the curve for sarcopenia was significantly larger for serum Cr/CysC ratio than for other biomarkers (Cr/CysC: 0.644, CysC: 0.535, Cr: 0.556). Patients in the high-Cr/CysC group have longer survival time than that in low-Cr/CysC group, defined by the cutoff value 0.67. The C-index of both Cr/CysC ratio and SMI with OS was 0.63. CONCLUSIONS: Serum Cr/CysC ratio can be used accurately, inexpensively, and easily to evaluate sarcopenia in male patients with gastric cancer. Our study shows that patients with Cr/CysC below 0.67 had possibility of sarcopenia and would be poor prognosis.


Asunto(s)
Sarcopenia , Neoplasias Gástricas , Biomarcadores , Creatinina , Cistatina C , Humanos , Masculino , Estudios Retrospectivos , Sarcopenia/diagnóstico , Sarcopenia/diagnóstico por imagen , Neoplasias Gástricas/complicaciones
9.
J Proteome Res ; 20(6): 3031-3042, 2021 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-34009990

RESUMEN

The aim of this study was to understand the molecular mechanisms behind the biological differences of X- and Y-sperm and to screen the sex-specific candidate antigen proteins for sexed semen production. To this end, we investigated differential expression of total membrane proteins of the two sperm types by using high-purity X- and Y-sperm from 20 Holstein bulls and applying the label-free proteomic technique; 1521 proteins were identified. In the X-sperm group, 8 and 23 proteins were significantly up- and down-regulated, respectively. In the X- and the Y-sperm group, 151 and 88 proteins were specifically expressed, respectively. These were overexpressed in the dynamic changes of the actin cytoskeleton, and cell senescence/apoptosis induced by the immune response, and could result in differences in the state, size, and immune sensitivity of the X-/Y-sperm membranes. The prediction of transmembrane structure, subcellular localization, and Western blotting validation results showed that the CLRN3 and SCAMP1 proteins were cell surface specific antigens of X- and Y-sperm, respectively. Our findings help explain the molecular mechanism behind the biological differences of X-/Y-sperm and lay the foundation for application of immunological methods to produce sex-sorted semen and control livestock sex. Data are available via ProteomeXchange with identifier PXD019435.


Asunto(s)
Preselección del Sexo , Cromosoma Y , Animales , Bovinos , Femenino , Masculino , Proteínas de la Membrana/genética , Proteómica , Espermatozoides , Cromosoma X
10.
Biochem Biophys Res Commun ; 566: 16-23, 2021 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-34111667

RESUMEN

With the aggravation of global aging, the rapid rise in the obesity rate, and the increasing number of patients with intervertebral disc degeneration (IDD), the principles and mechanism of this disease remain unclear. This study explored the molecular mechanism of IDD treatment through interactions of the lncRNA-miRNA-mRNA-signaling pathways and the effects on the proliferation and apoptosis of human nucleus pulposus cells (HNPCs) cultured in vitro. Our study revealed that lncRNA JPX is expressed at low levels in HNPCs under normoxic conditions. Luciferase and RNA pull-down assays were used to verify that lncRNA JPX directly bound to miR-18a-5p and influenced HNPC proliferation and apoptosis. Subsequently, a luciferase assay confirmed the direct binding of miR-18a-5p to HIF-1α and demonstrated a negative correlation between miR-18a-5p and HIF-1α. In addition, the HIF-1α antagonist reversed the inhibition of the Hippo-YAP pathway by the miR-18a-5p inhibitor. In conclusion, overexpression of lncRNA JPX upregulated HIF-1α by inhibiting the expression of miR-18a-5p, thereby inhibiting the Hippo-YAP pathway. By inhibiting this pathway, JPX overexpression promoted the proliferation of HNPCs and decreased their apoptosis. Therefore, the lncRNA JPX is a potential new target.


Asunto(s)
Apoptosis , Núcleo Pulposo/citología , ARN Largo no Codificante/genética , Transducción de Señal , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Línea Celular , Proliferación Celular , Vía de Señalización Hippo , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Núcleo Pulposo/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , ARN Largo no Codificante/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas Señalizadoras YAP
11.
RNA Biol ; 18(3): 368-381, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32794424

RESUMEN

RNA editing is an essential process for modifying nucleotides at specific RNA sites during post-transcription in many species. However, its genomic landscape and characters have not been systematically explored in the bovine genome. In the present study, we characterized global RNA editing profiles from 50 samples of cattle and revealed a range of RNA editing profiles in different tissues. Most editing sites were significantly enriched in specific BovB-derived SINEs, especially the dispersed Bov-tAs, which likely forms dsRNA structures similar to the primate-specific Alu elements. Interestingly, ADARB1 (ADAR2) was observed to be predominant in determining global editing in the bovine genome. Common RNA editing sites among similar tissues were associated with tissue-specific biological functions. Taken together, the wide distribution of RNA editing sites and their tissue-specific characters implied the bovine RNA editome should be further explored.


Asunto(s)
Genoma , Genómica , Edición de ARN , Adenosina Desaminasa/genética , Animales , Bovinos , Secuencia Conservada , Evolución Molecular , Regulación de la Expresión Génica , Genómica/métodos , Humanos , Ratones , Familia de Multigenes , Especificidad de Órganos , Secuencias Repetitivas de Ácidos Nucleicos , Elementos de Nucleótido Esparcido Corto , Especificidad de la Especie
12.
Asian-Australas J Anim Sci ; 33(11): 1725-1731, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32106650

RESUMEN

OBJECTIVE: An initial RNA-Sequencing study revealed that UDP-galactose-4-epimerase (GALE) was one of the most promising candidates for milk protein concentration in Chinese Holstein cattle. This enzyme catalyzes the interconversion of UDP-galactose and UDP-glucose, an important step in galactose catabolism. To further validate the genetic effect of GALE on milk protein traits, genetic variations were identified, and genotypes-phenotypes associations were performed. METHODS: The entire coding region and the 5'-regulatory region (5'-UTR) of GALE were re-sequenced using pooled DNA of 17 unrelated sires. Association studies for five milk production traits were performed using a mixed linear animal model with a population encompassing 1,027 Chinese Holstein cows. RESULTS: A total of three variants in GALE were identified, including two novel variants (g.2114 A>G and g.2037 G>A) in the 5'-UTR and one previously reported variant (g.3836 G>C) in an intron. All three single nucleotide polymorphisms (SNPs) were associated with milk yield (p<0.0001), fat yield (p = 0.0006 to <0.0001), protein yield (p = 0.0232 to <0.0001) and protein percentage (p<0.0001), while no significant associations were detected between the SNPs and fat percentage. A strong linkage disequilibrium (D' = 0.96 to 1.00) was observed among all three SNPs, and a 5 Kb haplotype block involving three main haplotypes with GAG, AGC, and AGG was formed. The results of haplotype association analyses were consistent with the results of single locus association analysis (p<0.0001). The phenotypic variance ratio above 3.00% was observed for milk protein yield that was explained by SNP-g.3836G >C. CONCLUSION: Overall, our findings provided new insights into the polymorphic variations in bovine GALE gene and their associations with milk protein concentration. The data indicate their potential uses for marker-assisted breeding or genetic selection schemes.

13.
Int J Mol Sci ; 20(13)2019 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-31252692

RESUMEN

Mitochondria are crucial cellular organelles in eukaryotes and participate in many cell processes including immune response, growth development, and tumorigenesis. Marek's disease (MD), caused by an avian alpha-herpesvirus Marek's disease virus (MDV), is characterized with lymphomas and immunosuppression. In this research, we hypothesize that mitochondria may play roles in response to MDV infection. To test it, mitochondrial DNA (mtDNA) abundance and gene expression in immune organs were examined in two well-defined and highly inbred lines of chickens, the MD-susceptible line 72 and the MD-resistant line 63. We found that mitochondrial DNA contents decreased significantly at the transformation phase in spleen of the MD-susceptible line 72 birds in contrast to the MD-resistant line 63. The mtDNA-genes and the nucleus-genes relevant to mtDNA maintenance and transcription, however, were significantly up-regulated. Interestingly, we found that POLG2 might play a potential role that led to the imbalance of mtDNA copy number and gene expression alteration. MDV infection induced imbalance of mitochondrial contents and gene expression, demonstrating the indispensability of mitochondria in virus-induced cell transformation and subsequent lymphoma formation, such as MD development in chicken. This is the first report on relationship between virus infection and mitochondria in chicken, which provides important insights into the understanding on pathogenesis and tumorigenesis due to viral infection.


Asunto(s)
ADN Mitocondrial/genética , Enfermedad de Marek/genética , Animales , Proteínas Aviares/genética , Proteínas Aviares/metabolismo , Pollos , ADN Polimerasa Dirigida por ADN/genética , ADN Polimerasa Dirigida por ADN/metabolismo , Resistencia a la Enfermedad/genética , Enfermedad de Marek/inmunología , Mitocondrias/genética , Mitocondrias/metabolismo , Mitocondrias/virología , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Bazo/metabolismo , Bazo/virología , Regulación hacia Arriba
14.
BMC Genet ; 18(1): 63, 2017 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-28673243

RESUMEN

BACKGROUND: Using a genome-wide association study strategy, our previous study discovered 19 significant single-nucleotide polymorphisms (SNPs) related to semen production traits in Chinese Holstein bulls. Among them, three SNPs were within or close to the phosphodiesterase 3A (PDE3A), membrane associated ring-CH-type finger 1 (MARCH1) and platelet derived growth factor receptor beta (PDGFRB) genes. The present study was designed with the objectives of identifying genetic polymorphism of the PDE3A, PDGFRB and MARCH1 genes and their effects on semen production traits in a Holstein bull population. RESULTS: A total of 20 SNPs were detected and genotyped in 730 bulls. Association analyses using de-regressed estimated breeding values of each semen production trait revealed four statistically significant SNPs for one or more semen production traits (P < 0.05): one SNP was located downstream of PDGFRB and three SNPs were located in the promoter of MARCH1. Interestingly, for MARCH1, haplotype-based analysis revealed significant associations of haplotypes with semen volume per ejaculate. Furthermore, high expression of the MARCH1 gene was observed in sperm cells. One SNP (rs43445726) in the regulatory region of MARCH1 had a significant effect on gene expression. CONCLUSION: Our study demonstrated the significant associations of genetic variants of the PDGFRB and MARCH1 genes with semen production traits. The identified SNPs may serve as genetic markers to optimize breeding programs for semen production traits in Holstein bull populations.


Asunto(s)
Bovinos/genética , Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genética , Semen/fisiología , Ubiquitina-Proteína Ligasas/genética , Animales , Bovinos/fisiología , China , Masculino , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Análisis de Semen , Motilidad Espermática/fisiología , Ubiquitina-Proteína Ligasas/metabolismo
16.
J Invest Surg ; 37(1): 2350358, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38724045

RESUMEN

OBJECTIVES: Hypermetabolism is associated with clinical prognosis of cancer patients. The aim of this study was to explore the association between basal metabolic rate (BMR) and postoperative clinical outcomes in gastric cancer patients. METHODS: We collected data of 958 gastric cancer patients admitted at our center from June 2014 to December 2018. The optimal cutoff value of BMR (BMR ≤1149 kcal/day) was obtained using the X-tile plot. Logistic and Cox regression analyses were then performed to evaluate the relevant influencing factors of clinical outcomes. Finally, R software was utilized to construct the nomogram. RESULTS: A total of 213 patients were defined as having a lower basal metabolic rate (LBMR). Univariate and multivariate analyses showed that gastric cancer patients with LBMR were more prone to postoperative complications and had poor long-term overall survival (OS). The established nomogram had good predictive power to assess the risk of OS in gastric cancer patients after radical gastrectomy (c-index was 0.764). CONCLUSIONS: Overall, LBMR on admission is associated with the occurrence of postoperative complications in gastric cancer patients, and this population has a poorer long-term survival. Therefore, there should be more focus on the perioperative management of patients with this risk factor before surgery.


Asunto(s)
Metabolismo Basal , Gastrectomía , Nomogramas , Complicaciones Posoperatorias , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirugía , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Masculino , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Gastrectomía/efectos adversos , Gastrectomía/métodos , Anciano , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Pronóstico , Factores de Riesgo , Resultado del Tratamiento , Adulto
17.
Environ Sci Pollut Res Int ; 31(2): 2053-2066, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38049689

RESUMEN

In cement industry, the selection of catalyst temperature window and the inhibition effect of dust composition in flue gas on catalyst are the key issues of flue gas denitrification. In this article, a pilot study with Ce doped V-W/Ti catalyst on the removal of NOx by selective catalytic reduction with ammonia (NH3-SCR) from the cement kiln flue gas was presented. Cement kiln dust loading on catalysts obviously decreased the NO conversion in the absence of SO2 and H2O, while the denitration efficiency restored from 75 to 98% at 280 ℃ after SO2 and H2O introduced into the reaction system, which mainly because the SO2 may enhance the acidic site on the catalyst surface, and prefer to be bonded with the coordinated Ca species, releasing the active sites poisoned by dust. The NH3-temperature programmed desorption (NH3-TPD), X-ray photoelectron spectroscopy (XPS), and H2-temperature programmed reduction (H2-TPR) detections were performed to reveal that the appropriate Ce and W ratios catalyst contributed better denitrification activity. The optimum ratio of Ce doped catalyst was amplified to form the standard honeycomb monomer catalyst, and then, the activity of catalyst was verified on the side line of cement kiln. The effect of temperature and space velocity on denitrification efficiency was investigated, and the denitration efficiency reached to 92.5% at 300℃ and 3000 h-1 space velocity. Moreover, the life of catalyst was verified and predicted by GM (1,1) grey model. The study realized the innovation from the laboratory data rules to the industrial pilot application, providing positive promoting value for the industrial large-scale demonstration application of the catalyst.


Asunto(s)
Amoníaco , Titanio , Oxidación-Reducción , Titanio/química , Proyectos Piloto , Temperatura , Amoníaco/química , Catálisis , Polvo
18.
Evol Appl ; 17(2): e13638, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38333555

RESUMEN

Genomic selection (GS) has great potential to increase genetic gain in poultry breeding. However, the performance of genomic prediction in duck growth and breast morphological (BM) traits remains largely unknown. The objective of this study was to evaluate the benefits of genomic prediction for duck growth and BM traits using methods such as GBLUP, single-step GBLUP, Bayesian models, and different marker densities. This study collected phenotypic data for 14 growth and BM traits in a crossbreed population of 1893 Pekin duck × mallard, which included 941 genotyped ducks. The estimation of genetic parameters indicated high heritabilities for body weight (0.54-0.72), whereas moderate-to-high heritabilities for average daily gain (0.21-0.57) traits. The heritabilities of BM traits ranged from low to moderate (0.18-0.39). The prediction ability of GS on growth and BM traits increased by 7.6% on average compared to the pedigree-based BLUP method. The single-step GBLUP outperformed GBLUP in most traits with an average of 0.3% higher reliability in our study. Most of the Bayesian models had better performance on predictive reliability, except for BayesR. BayesN emerged as the top-performing model for genomic prediction of both growth and BM traits, exhibiting an average increase in reliability of 3.0% compared to GBLUP. The permutation studies revealed that 50 K markers had achieved ideal prediction reliability, while 3 K markers still achieved 90.8% predictive capability would further reduce the cost for duck growth and BM traits. This study provides promising evidence for the application of GS in improving duck growth and BM traits. Our findings offer some useful strategies for optimizing the predictive ability of GS in growth and BM traits and provide theoretical foundations for designing a low-density panel in ducks.

19.
Appl Opt ; 52(34): 8381-7, 2013 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-24513842

RESUMEN

The luminous distribution characteristics of light sources can be measured by goniophotometry. In this work, the misalignment of luminary-induced measurement errors as the main factor affecting the measurement accuracy is analyzed. A calculation method for measurement error is proposed. Then, the translational and angular misalignment-induced measurement errors are calculated and analyzed. Results show that the measurement errors induced by misalignments may be great in some cases even if the far-field condition is satisfied. For luminaries with different radiation patterns, the acceptable misalignment tolerances corresponding to measurement error of less than 1% are given.

20.
Appl Opt ; 52(8): 1629-35, 2013 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-23478765

RESUMEN

Most of the lighting designs are based on the far-field characteristics of light sources. It is important to know whether the measurement distance is far enough to simulate the light source as a point source. In this paper, we deduce the far-field conditions for surface light sources with continuous luminous area. The relative far-field distance for several typical flat and curved surface light sources, such as the round, rectangular, annular, hemispherical, and semi-cylindrical sources are calculated. Results show that the classical five times rule is not applicable to surface light sources with hemispherical, arc-shaped semi-cylindrical, and narrow annular luminous areas.

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