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1.
J Environ Manage ; 355: 120460, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38430881

RESUMO

The practice of returning straw to agricultural fields is a globally employed technique. Such agricultural fields also receive a significant amount of nitrogen (N) and phosphorus (P) fertilizers, because these two macronutrients are essential for plant growth and development. However, the consequences of such macronutrients input on straw decomposition, soil dissolved organic matter (DOM), key microbes, and lignocellulolytic enzymes are still unclear. In a similar aim, we designed a long-term straw returning study without and with different N and P nutrient supplementation: CK (N0P0), T1 (N120P0), T2 (N120P60), T3 (N120P90), T4 (N120P120), T5 (N0P90), T6 (N60P90), and T7 (N180P90), and evaluated their impact on rice and oilseed rape yield, soil DOM, enzymes, lignocellulose content, microbial diversity, and composition. We found straw returning improved overall yield in all treatments and T7 showed the highest yield for oilseed rape (30.31-38.87 g/plant) and rice (9.14-9.91 t/ha) during five-years of study. The fertilizer application showed a significant impact on soil physicochemical properties, such as water holding capacity and soil porosity decreased, and bulk density increased in fertilized treatments, as compared to CK. Similarly, significantly low OM, cellulose, hemicellulose, and lignin content were found in T7, T4, T3, and T2, while high values were found in CK and T5, respectively. The fluorescence excitation-emission matrix spectra of DOM of different treatments revealed that T3, T7, T4, and T6 showed high peak M (microbial by-products), peak A and peak C (humic acid-like) as compared to others. The microbial composition was also distinctive in each treatment and a high relative abundance of Chloroflexi, Actinobacteriota, Ascomycota, and Basidiomycota were found in T2 and T3 treatments, respectively. These findings indicate that the decomposition of straw in the agricultural field was dependent on nutrients input, which facilitated key microbial growth and impacted positively on lignocellulolytic enzymes, which further aided the breakdown of all components of straw in the field efficiently. On the other hand, high input of chemical based fertilizers to soil can lead to several environmental issues, such as nutrient imbalance, nutrient runoff, soil pH change and changes in microbial activities. Keeping that in consideration, we recommend moderate fertilizer dosage (N120P90) in such fields to achieve higher decomposition of crop straw with a small yield compromise.


Assuntos
Fertilizantes , Oryza , Agricultura/métodos , Solo/química , Substâncias Húmicas , Nitrogênio/análise
2.
Molecules ; 28(17)2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37687073

RESUMO

Vinyl acetate is a restricted substance in food products. The quantification of the organic impurities in vinyl acetate is a major problem due to its activity, instability, and volatility. In this paper, while using the mass balance method to determine the purity of vinyl acetate, an improved method was established for the determination of the content of three impurities in vinyl acetate reference material, and the GC-FID peak area normalization for vinyl acetate was calibrated. The three trace organic impurities were identified by gas chromatography tandem high-resolution mass spectrometry to be methyl acetate, ethyl acetate, and vinyl propionate. The content and relative correction factors for the three organic impurities were measured. The purity of vinyl acetate determined by the mass balance method was 99.90% with an expanded uncertainty of 0.30%, and the total content of organic impurities was 0.08% with a relative correction factor of 1.23%. The vinyl acetate reference material has been approved as a national certified reference material in China as GBW (E) 062710.

3.
J Sci Food Agric ; 103(14): 7302-7313, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37499162

RESUMO

BACKGROUND: Chalkiness in rice reduces its market value and affects consumer acceptance. Research on the mechanism of chalkiness formation has focused primarily on the activity of key enzymes of carbon metabolism and starch accumulation. The relationship between the formation of chalkiness induced by N fertilizer and rice starch's multi-level structure and thermal properties still needs to be fully elucidated. RESULTS: In this study, the rates of chalky grains and degree of chalkiness decreased with the increase in N fertilizer dosage. This was attributed to an increased proportion of short chains, ordered structure carbon chains, small starch granules, and branched starches, and a higher degree of crystallinity and ΔHg in protein, and a decreased proportion of amylose, large starch granules, and weighted average diameter of starch granule surface area and volume. Application of N fertilizer promoted an increased proportion of short-branched chain amylopectin to develop a more ordered carbohydrate structure and crystalline lamella. These effects enhanced the normal development and compactness of starch granules in grains, and improved their arrangement morphology, thereby reducing the chalkiness in rice. CONCLUSION: These changes in starch multi-level structure and protein improve the physicochemical characteristics of starch and enhance the fullness, crystallinity and compactness of starch granules, while synergistically increasing the regularity and homogeneity of starch granules and thus optimizing the stacking pattern of starch granules, leading to a reduction in rice chalkiness under nitrogen fertilization and thus improving the appearance of rice. © 2023 Society of Chemical Industry.

4.
Angew Chem Int Ed Engl ; 62(40): e202309882, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37603411

RESUMO

The direct seawater electrolysis at high current density and low overpotential affords an effective strategy toward clean and renewable hydrogen fuel production. However, the severe corrosion of anode as a result of the saturation of Cl- upon continuous seawater feeding seriously hamper the electrolytic process. Herein, cobalt ferricyanide / cobalt phosphide (CoFePBA/Co2 P) anodes with Cap/Pin structure are synthesized, which stably catalyze alkaline saturated saline water oxidation at 200-2000 mA cm-2 over hundreds of hours without corrosion. Together with the experimental findings, the molecular dynamics simulations reveal that PO4 3- and Fe(CN)6 3- generated by the electrode play synergistic role in repelling Cl- via electrostatic repulsion and dense coverage, which reduced Cl- adsorption by nearly 5-fold. The novel anionic synergy endow superior corrosion protection for the electrode, and is expected to promote the practical application of saline water electrolysis.

5.
Pak J Pharm Sci ; 36(4(Special)): 1313-1317, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37606021

RESUMO

Protection roles of serum vitamin D levels in the cardiovascular system. This observational study enrolled 286 young ACI patients with type 2 diabetes mellitus in our Hospital from October 2016 to April 2020 as the study group. 127 healthy individuals as the control group. Serum levels of vitamin D and blood pressure indexes of the two groups were measured and the correlation between vitamin D levels and the clinical phenotype of young cerebral infarction was explored. Significantly higher 25-hydroxyvitamin D was observed in the study group vs. control group. During the day, The values of systolic and diastolic blood pressure and mean blood pressure was well-balanced between the two groups. However, at night and within 24 hours, significant differences in systolic and diastolic blood pressure and mean value were observed between the two groups. The higher the vitamin D level, the greater the decrease in blood pressure at night. Serum 25-hydroxyvitamin D was positively correlated with the reduction of night systolic and diastolic blood pressure. Low levels of 25-hydroxyvitamin D led to a small decrease in blood pressure at night, resulting in a vulnerable cardiovascular system and an increased incidence of cerebral infarction in the young population.


Assuntos
Sistema Cardiovascular , Diabetes Mellitus Tipo 2 , Humanos , Pressão Sanguínea , Vitamina D , Infarto Cerebral
6.
Gerontology ; 68(8): 854-860, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34607327

RESUMO

INTRODUCTION: Guillain-Barré syndrome (GBS) is a common autoimmune disease in the peripheral nervous system. This study aimed to elucidate the role of IL-27 gene polymorphisms in elderly people with GBS. METHODS: A total of 395 healthy subjects and 422 GBS patients with an average age of 63 years old were included in this study. Peripheral blood samples were collected. The 2 single-nucleotide polymorphisms (SNPs) of IL-27, namely, rs153109 and rs785575, of GBS patients were analyzed using the PCR method and compared with those of the healthy controls. The correlations of IL-27 SNPs with disease severity, disease outcome, level of anti-GM1 antibodies, and Campylobacter jejuni infection were assessed. Serum levels of IL-27 of healthy subjects and GBS patients were analyzed using enzyme-linked immunosorbent assay. RESULTS: No significant differences in the frequencies of rs785575 SNPs between GBS and healthy subjects were observed. In analyzing rs153109 SNPs, the G allele was found to be more prevalent in the GBS patients (p = 0.012). More alleles show GG genotype in GBS patients (p = 0.023). The -964A>G allele has a higher prevalence in severely affected and anti-GM1-Ab-positive GBS patients. GBS patients with the rs153109 SNP showed a poor clinical outcome than those without rs153109 SNP (p = 0.012). GBS patients showed higher serum IL-27 levels than healthy subjects (p < 0.001). The levels of IL-27 were also higher in GBS patients with genotypes of AG and GG, and those with GG genotypes showed the highest IL-27 levels. CONCLUSION: The rs153109 SNP is more prevalent in GBS patients with the GG and G allele and is associated with severer GBS, poorer clinical outcomes, and higher IL-27 levels.


Assuntos
Síndrome de Guillain-Barré , Interleucina-27 , Idoso , Alelos , Genótipo , Síndrome de Guillain-Barré/genética , Humanos , Interleucina-27/genética , Interleucinas , Polimorfismo de Nucleotídeo Único
7.
Eur Spine J ; 31(11): 2920-2934, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35842490

RESUMO

BACKGROUND: The completeness of the intervertebral disc proteome is fundamental to the integrity and functionality of the intervertebral disc. METHODS: The 20 experimental rats were placed into two groups randomly, normal group (NG) and acupuncture pathological degeneration group-2 weeks (APDG-2w). The ten 24-month-old rats were grouped into physiological degeneration group (PDG). Magnetic resonance imaging, X-ray examination, histological staining (hematoxylin & eosin, safranin-O cartilage, and alcian blue staining), and immunohistochemical examination were carried out for assessing the degree of disc degradation. Intervertebral disc was collected, and protein composition was determined by LC- MS, followed by bioinformatic analysis including significance analysis, subcellular localization prediction, protein domain prediction, GO function and KEGG pathway analysis, and protein interaction network construction. LC-PRM was done for protein quantification. RESULTS: Physiological degeneration and especially needle puncture decreased T2 signal intensity and intervertebral disc height. Results from hematoxylin & eosin, safranin-O, and alcian blue staining revealed that the annulus fibrosus apparently showed the wavy and collapsed fibrocartilage lamellas in APDG-2w and PDG groups. The contents of the nucleus pulposus were decreased in physiological degeneration group and APDG-2w group compared with NG. Results from immunohistochemical analysis suggested the degeneration of intervertebral disc and inflammation in APDG-2w and PDG groups. The protein composition and expression between needle puncture rat models and the physiological degeneration group showed significant difference. CONCLUSIONS: Our studies produced point-reference datasets of normal rats, physiological degeneration rats, and needle puncture rat models, which is beneficial to subsequent pathological studies. There is differential expression of protein expression in degenerative discs with aging and acupuncture, which may be used as a potential discriminating index for different intervertebral degenerations.


Assuntos
Degeneração do Disco Intervertebral , Disco Intervertebral , Animais , Ratos , Azul Alciano/metabolismo , Modelos Animais de Doenças , Amarelo de Eosina-(YS)/metabolismo , Hematoxilina/metabolismo , Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/patologia , Proteômica , Punções
8.
Mol Biol Rep ; 48(12): 8009-8021, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34665398

RESUMO

BACKGROUND: Chemical fertilization helped modern agriculture in grain yield improvement to ensure food security. The response of chemical fertilization for higher hybrid rice production is highly dependent on optimal fertilization management in paddy fields. To assess such responses, in the current work we examine the yield, root growth, and expression of related genes responsible for stress metabolism of nitrogen (N) and phosphorus (P) in two hybrid-rice cultivars Deyou4727 (D47) and Yixiangyou2115 (Y21). METHODS AND RESULTS: The experiment followed four nitrogen (N) (N0, N60, N120, and N180 kg/ha) and phosphorus (P) (P0, P60, P90, and P120 kg/ha) fertilizer levels. The grain yield in D47 was more sensitive to nitrogen application, while Y21 was more sensitive to phosphorus application, which resulted in comparatively higher biomass and yield. Our findings were corroborated by gene expression studies of glutamine synthetase OsGS1;1 and OsGS1;2 and phosphate starvation-related genes PHR1 and SPX, confirming sensitivity to N and P application. The number of roots was less sensitive to nitrogen application in D47 between N0 and N60, but the overall nutrient response difference was significantly higher due to the deep rooting system as compared to Y21. CONCLUSIONS: The higher yield, high N and P use efficiency, and versatile root growth of D47 make it suitable to reduce unproductive usage of N and P from paddy fields, improving hybrid rice productivity, and environmental safety in the Sichuan basin area of China.


Assuntos
Agricultura/métodos , Oryza/genética , Oryza/metabolismo , Biomassa , China , Fertilizantes/análise , Nitrogênio/metabolismo , Nutrientes , Fósforo/metabolismo , Raízes de Plantas/metabolismo , Solo
9.
Appl Opt ; 59(6): 1529-1536, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32225652

RESUMO

Due to the severe interference from strong solar background light on the received signal, daytime ground-based lidar observation of the sodium (Na) layer is challenging. In this paper, a Na lidar permitting full-diurnal-cycle observation of the metal Na layer over Beijing, China (40.5°N, 116°E) was reported. In order to suppress the skylight background during daytime effectively with less signal losses, a dual-channel Faraday filtering unit was implemented in the lidar receiver. Based on the diurnal Na lidar system, a good number of continuous observational results that lasted more than 120 h with good signal-to-noise ratio were obtained, demonstrating its reliability. Considerable variations within the Na layer during the day were revealed, especially on the layer top and bottom side. In particular, strong sporadic Na layer (Nas) events that occurred during the daytime of 3 consecutive days were also captured with complete evolution process. These observational results showed the advantages of the diurnal Na lidar for investigating the metal layer photochemistry and dynamics in the mesosphere and lower thermosphere region. Na layer observations over the whole diurnal cycle not only benefit the improvements of current theoretical models, but also can allow for a specialized analysis of Nas that occur in the daytime and provide valuable observational support for investigating the rapid production and disappearance mechanisms of Na atoms.

10.
Appl Opt ; 59(13): 4122-4130, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32400688

RESUMO

A dual-wavelength tunable lidar system that simultaneously detects the Ca and Ca+ layers has been established in Yanqing Station (40.41°N, 116.01°E). The lidar system implements a pulsed Nd:YAG laser that simultaneously pumps two dye lasers, which reduces the hardware configuration of the lidar system. The two dye lasers use infrared laser dyes with high conversion efficiency suitable for long-term observation. The resonance wavelengths of Ca and Ca+ are generated by frequency doubling of the two infrared laser beams. We compared the dual-wavelength tunable lidar system to previous dye-based systems and performed experiments to determine resonance frequencies to within 0.4 pm and to test the dual optical fiber receiving system and found it does not cause cross talk. Three nights of preliminary simultaneous observations of Ca and Ca+ layers are reported; the diversity of these observations begs for more systematic observations and challenging interpretations in terms of Ca processes in the ionosphere and illustrates the effectiveness of this system for aeronomy and space physics studies.

11.
J Cell Physiol ; 234(5): 6336-6349, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30246250

RESUMO

1,7-Bis(4-hydroxyphenyl)-1,4-heptadien-3-one (EB30) is a diarylheptanoid-like compound isolated from Viscum coloratum. This curcumin analog exhibits significant cytotoxic activity against HeLa, SGC-7901, and MCF-7 cells. However, little is known about the anticancer effects and mechanisms of EB30 in human lung cancer. The current study reports that EB30 significantly reduced the cell viability of A549 and NCI-H292 human lung cancer cells. Further examination revealed that EB30 not only induced cell cycle arrest and promoted the generation of reactive oxygen species (ROS) but also induced cell apoptosis through the intrinsic and extrinsic signaling pathways. Furthermore, EB30 upregulated the expression levels of p-ERK1/2 and p-P90RSK, whereas downregulating the phosphorylation of Akt and P70RSK. Cell viability was further inhibited by the combination of EB30 with LY294002 (a specific PI3K inhibitor) or U0126 (a MEK inhibitor). The current study indicates that EB30 is a potential anticancer agent that induces cell apoptosis via suppression of the PI3K/Akt pathway and activation of the ERK1/2 pathway.


Assuntos
Antineoplásicos/farmacologia , Curcumina/análogos & derivados , Neoplasias Pulmonares , Extratos Vegetais/farmacologia , Transdução de Sinais/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/fisiologia , Fosfatidilinositol 3-Quinases/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Viscum/química
12.
Int J Mol Sci ; 20(3)2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-30754644

RESUMO

Light is one of the most important environmental factors that affect many aspects of plant growth, including chlorophyll (Chl) synthesis and flowering time. Here, we identified a rice mutant, yellow leaf and early flowering (ye1), and characterized the gene YE1 by using a map-based cloning method. YE1 encodes a heme oxygenase, which is localized to the chloroplasts. YE1 is expressed in various green tissues, especially in leaves, with a diurnal-rhythmic expression pattern, and its transcripts is also induced by light during leaf-greening. The mutant displays decreased Chl contents with less and disorderly thylakoid lamellar layers in chloroplasts, which reduced the photosynthesis rate. The early flowering phenotype of ye1 was not photoperiod-sensitive. Furthermore, the expression levels of Chl biosynthetic genes were downregulated in ye1 seedlings during de-etiolation responses to light. We also found that rhythmic expression patterns of genes involved in photoperiodic flowering were altered in the mutant. Based on these results, we infer that YE1 plays an important role in light-dependent Chl biogenesis as well as photoperiodic flowering pathway in rice.


Assuntos
Clorofila/biossíntese , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Redes e Vias Metabólicas , Oryza/genética , Oryza/metabolismo , Fotossíntese , Cloroplastos/metabolismo , Evolução Molecular , Flores/genética , Mutação , Fenótipo , Filogenia , Análise de Sequência de DNA
13.
Opt Express ; 25(5): 5264-5278, 2017 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-28380790

RESUMO

A solid-state sodium (Na) Doppler lidar developed at YanQing Station, Beijing, China (40°N, 116°E) aiming to simultaneous wind and temperature measurement of mesopause region was reported. The 589 nm pulse laser was produced by two injection seeded 1064 nm and 1319 nm Nd:YAG pulse lasers using the sum-frequency generation (SFG) technique. A fiber amplifier is implemented to boost the seed power at 1064 nm, enabling a robust, all-fiber-coupled design for seeding laser unit, absolute laser frequency locking, and cyclic three-frequency switching necessary for simultaneous temperature and wind measurements. The all-fiber-coupled injection seeding configuration together with the solid-state Nd:YAG lasers make the Na Doppler lidar more compact and greatly reduce the system maintenance, which is conducive to transportable and unattended operation. A preliminary observational result obtained with this solid-state sodium Doppler lidar was also reported in this paper.

14.
World J Surg Oncol ; 15(1): 145, 2017 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-28768544

RESUMO

BACKGROUND: Accurate intraoperative localization of esophageal lesions is essential for successful surgical resection. We tested whether preoperative endoscopic placement of titanium clips could facilitate intraoperative localization of early-stage esophageal cancer or severe dysplasia. METHODS: A prospective randomized clinical trial was performed between May 2012 and July 2014. All enrolled patients received preoperative endoscopy and esophageal endoscopic ultrasound, as well as pathological study on the biopsy specimen, to confirm early stage esophageal cancer or severe dysplasia. One day before the surgical operation, patients in the experimental group received the preoperative endoscopic titanium labeling of esophageal lesions. Then, during the surgical operation, palpitation of titanium clips was used to localize the lesions in these patients. In patients in the control group, palpitation of nodules or esophageal wall mucosal thickening, together with the consideration of the results from preoperative endoscopic and ultrasound studies, was applied to estimate the location of the esophageal lesions. Study outcomes included the proportions of patients having successful intraoperative pre-resection lesion localization, post-esophagectomy lesion visualization, negative upper surgical margin, change of surgical approaches, and positive postoperative pathological diagnosis. RESULTS: A total of 27 patients were enrolled into the study, with 14 in the experimental group and 13 in the control group. Compared to the patients in the control group, a higher proportion of patients in the experimental group had statistically significant successful intraoperative esophageal lesion localization (100 versus 15.3% in the experimental versus control group). CONCLUSIONS: Preoperative endoscopic titanium clip placement could facilitate intraoperative localization of early-stage esophageal cancer or severe dysplasia. TRIAL REGISTRATION: Current study was registered in Chinese Clinical Trial Registry and World Health Organization International Clinical Trials Registry Platform, ChiCTR-INR-17010949 . Registered 22 March 2017, retrospectively registered.


Assuntos
Neoplasias Esofágicas/cirurgia , Esofagectomia/instrumentação , Esofagoscopia/instrumentação , Esôfago/patologia , Cuidados Pré-Operatórios/métodos , Idoso , Biópsia , Conversão para Cirurgia Aberta/estatística & dados numéricos , Endossonografia , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/patologia , Esofagectomia/efeitos adversos , Esofagectomia/métodos , Esofagoscopia/efeitos adversos , Esofagoscopia/métodos , Esôfago/diagnóstico por imagem , Esôfago/cirurgia , Feminino , Humanos , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Instrumentos Cirúrgicos , Titânio
15.
Yi Chuan ; 38(1): 72-81, 2016 01.
Artigo em Chinês | MEDLINE | ID: mdl-26787525

RESUMO

Using ethyl methanesulfonate (EMS) mutagenesis, we isolated an erect panicle mutant, R1338, from indica heavy-panicle restorer Shuhui498. Compared with wild type control, the mutant displayed dwarfism, erect and short panicle, short primary panicle branch, increased grain density, short grain length and increased grain thickness. In addition, the erect panicle architecture of R1388 resulted in significant decreased bending moment and increased resistance to panicle bending. Histocytological analysis indicated that the diameter of uppermost internode, cellulose content and lignin content play important roles in resistance to panicle bending. Genetic analysis revealed that the mutant phenotype was controlled by a semi-dominant nuclear gene. With resequencing and MutMap analysis strategy, we found that one SNP from A to G at the seventh exon of DEP2 resulted in the 928(th) amino acid substitution from arginine (AGG) to glycine (GGG) in R1338 mutant. Considering the phenotype of other dep2 mutants, the phenotype of R1338 was likely to be caused by the SNP in DEP2. The mutant R1338 and wild type were crossed with several sterile lines which respectively had different panicle types, the combinations generated from R1338 and curve panicle sterile lines showed semi-erect panicle, higher seed setting percentage and heterosis, and the combinations generated from R1388 and erect panicle sterile line with DEP1 showed erect panicle by gene additive effect. Moreover, the combinations with semi-erect panicle had superior light transmittance and stronger light intensity, which improved efficiency of light utilization to intermediate and subjacent leaves compared to the combinations with curved panicle. This study provides a good strategy to solve the problem of population density in three-line hybrid rice.


Assuntos
Oryza/genética , Proteínas de Plantas/genética , Alelos , Sequência de Bases , Cruzamento , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Proteínas de Plantas/metabolismo
16.
Sci Rep ; 14(1): 18836, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138371

RESUMO

The rail profile milling process allows considerable thickness to be removed in a single pass. However, the residual waviness formation law after milling and its subsequent effect on rail performance remains uncertain. In this paper, the wavelength and wave height of the residual waviness are identified as the key characteristics. The relationship between milling speed and residual waviness is determined, and a numerical model of the residual waviness formed on the surface after milling is established based on the commonly used three milling speeds of 300, 600, and 1000 m/h, and its accuracy is verified using the parameters of the residual waviness detected by the milling experiments. A three-dimensional finite element analysis model of wheel-rail contact was employed to analyze the contact stresses and low fatigue cycles at a wheel load of 11.5 tons with no residual waviness on the rail profile surface and with three types of residual waviness, respectively. The results show that the residual waviness changes the wheel-rail contact position and the morphology of the contact area, reduces the maximum contact stress and increases the strain fatigue cycles. The application of elevated milling speeds reduces the wheel-rail contact stresses after milling, thereby increasing the low fatigue cycles.

17.
One Health ; 19: 100859, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39157651

RESUMO

Antimicrobial resistance caused by the overuse of antimicrobials by farmers is an essential health issue. Currently, signing contracts between farmers and cooperatives has become crucial for small farmers to integrate into the modern agricultural industry chain. Unlike vertical government governance, which aims to intervene in the overuse of antimicrobials by farmers through many mandatory or incentive measures, contract governance refers to the social governance model that clarifies rights and obligations between farmers and cooperatives to ensure the adequate performance of contracts, which is especially beneficial to regulate farmers' safe production behavior such as the standard use of antimicrobials. However, there is a research gap concerning the effectiveness of contract governance in inhibiting farmers' overuse of animal antimicrobials. This study applies propensity score matching and mediation analysis method to assess how contract governance affects the overuse of antimicrobials by hog farmers. The paper uses data from 498 hog farmers of China's Hebei, Henan, and Hubei provinces to explore the impact and underlying mechanisms of contract governance on antimicrobial overuse in agriculture. The results showed that contract governance was found to inhibit the overuse of antimicrobials, with the amount paid for antimicrobials reduced by 118 yuan/household. We found evidence that this effect is exerted through three mechanisms: cooperative supervision (CS), technical guidance (TG), and product premium perception (PP). The CS, TG, and PP mediation effects accounted for 19.94%, 27.90%, and 26.93% of the total impact, respectively. Therefore, policy implications of these results include strengthening the standard of contract signing procedures and the integrity of executing contracts, increasing the market premium for products that meet the antimicrobial residue standards, and enhancing farmers' knowledge and contracting ability.

18.
Plants (Basel) ; 13(15)2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39124153

RESUMO

Panicle-type structure is an important factor affecting rice yield, and an excellent panicle type has become a key indicator in rice breeding. In this study, the indica rice variety R766, which has an open panicle type, was obtained through natural mutation and hybrid selection. Through analyzing differences in panicle structure, panicle yield, and chemical composition between open panicle rice R766 and conventional panicle rice R2928, we found that the angles of the middle and lower branches in R766 were 186.99% and 135.93% greater than those in R2928, respectively. By comparing the grain-filling characteristics of different panicle positions in the two rice varieties, we found that the grain filling at the middle and lower panicle positions of R2928 was significantly lower, accompanied by an increase in the percentage of empty spikelets. However, in R766, the grain-filling rates in the middle and lower panicle positions were consistent with those in the upper panicle position, with significantly higher rates of grain filling and grain plumpness in the middle and lower panicle positions than in R2928. The empty grain rate at the lower panicle position of R766 was 15.25% lower than that of R2928, and the grain filling was 24.75% higher than that of R2928. Additionally, the variation in the 1000-grain weight of grains at different panicle positions in R766 was relatively small, with decreases of 1.55% and 0.38% in the middle and lower panicle positions, respectively, compared with the upper position, whereas R2928 showed decreases of 5.99% and 7.12% in the 1000-grain weight of grains at the middle and lower panicle positions, respectively, compared with the upper position. The cellulose content in the stems of R766 was 7.51% higher than that of R2928, with no significant difference in the cellulose content in the panicle axis and primary branches compared to R2928. The lignin content of the panicle axis in R766 was 8.03% higher than that in R2928, whereas there was no significant difference between the lignin content of the stems and primary branches. This preliminary study revealed the open panicle characteristics of R766 and the reasons for its high basal grain setting rate. This study provides a reference for promoting this open panicle-type indica rice variety to improve yield and disease resistance in environments with high humidity and low sunlight levels.

19.
Nat Commun ; 15(1): 1973, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438342

RESUMO

Seawater electrolysis offers a renewable, scalable, and economic means for green hydrogen production. However, anode corrosion by Cl- pose great challenges for its commercialization. Herein, different from conventional catalysts designed to repel Cl- adsorption, we develop an atomic Ir catalyst on cobalt iron layered double hydroxide (Ir/CoFe-LDH) to tailor Cl- adsorption and modulate the electronic structure of the Ir active center, thereby establishing a unique Ir-OH/Cl coordination for alkaline seawater electrolysis. Operando characterizations and theoretical calculations unveil the pivotal role of this coordination state to lower OER activation energy by a factor of 1.93. The Ir/CoFe-LDH exhibits a remarkable oxygen evolution reaction activity (202 mV overpotential and TOF = 7.46 O2 s-1) in 6 M NaOH+2.8 M NaCl, superior over Cl--free 6 M NaOH electrolyte (236 mV overpotential and TOF = 1.05 O2 s-1), with 100% catalytic selectivity and stability at high current densities (400-800 mA cm-2) for more than 1,000 h.

20.
Opt Express ; 21(6): 7768-85, 2013 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-23546158

RESUMO

For high power-aperture lidar sounding of wide atmospheric dynamic ranges, as in middle-upper atmospheric probing, photomultiplier tubes' (PMT) pulse pile-up effects and signal-induced noise (SIN) complicates the extraction of information from lidar return signal, especially from metal layers' fluorescence signal. Pursuit for sophisticated description of metal layers' characteristics at far range (80~130km) with one PMT of high quantum efficiency (QE) and good SNR, contradicts the requirements for signals of wide linear dynamic range (i.e. from approximate 10(2) to 10(8) counts/s). In this article, Substantial improvements on experimental simulation of Lidar signals affected by PMT are reported to evaluate the PMTs' distortions in our High Power-Aperture Sodium LIDAR system. A new method for pile-up calibration is proposed by taking into account PMT and High Speed Data Acquisition Card as an Integrated Black-Box, as well as a new experimental method for identifying and removing SIN from the raw Lidar signals. Contradiction between the limited linear dynamic range of raw signal (55~80km) and requirements for wider acceptable linearity has been effectively solved, without complicating the current lidar system. Validity of these methods was demonstrated by applying calibrated data to retrieve atmospheric parameters (i.e. atmospheric density, temperature and sodium absolutely number density), in comparison with measurements of TIMED satellite and atmosphere model. Good agreements are obtained between results derived from calibrated signal and reference measurements where differences of atmosphere density, temperature are less than 5% in the stratosphere and less than 10K from 30km to mesosphere, respectively. Additionally, approximate 30% changes are shown in sodium concentration at its peak value. By means of the proposed methods to revert the true signal independent of detectors, authors approach a new balance between maintaining the linearity of adequate signal (20-110km) and guaranteeing good SNR (i.e. 10(4):1 around 90km) without debasing QE, in one single detecting channel. For the first time, PMT in photon-counting mode is independently applied to subtract reliable information of atmospheric parameters with wide acceptable linearity over an altitude range from stratosphere up to lower thermosphere (20-110km).


Assuntos
Algoritmos , Atmosfera/análise , Atmosfera/química , Lasers , Fotometria/instrumentação , Radar/instrumentação , Refratometria/instrumentação , Calibragem , Desenho de Equipamento , Análise de Falha de Equipamento
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