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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(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.

10.
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.

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.
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.

17.
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
18.
Front Aging Neurosci ; 15: 1244191, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37876876

RESUMO

Objective: To investigate the effects of brain-derived neurotrophic factor (BDNF) gene polymorphism on cognitive function, neuroimaging and blood biological markers in patients with subcortical ischaemic vascular dementia (SIVD). Methods: A total of 81 patients with SIVD were included. According to their BDNF gene polymorphism, the participants were divided into the Val/Val (n = 26), Val/Met (n = 35), and Met/Met (n = 20) groups. A comprehensive neuropsychological evaluation and multimodal brain MRI scan were performed. MRI markers for small vessel disease were visually rated or quantitatively analysed. Moreover, 52 patients were further evaluated with blood marker assays, including amyloid beta (Aß), phosphorylated tau at threonine-181 (P-tau181), glial fibrillary acidic protein (GFAP), total tau (T-tau) and neurofilament light chain (NfL). Results: There were no significant differences in demographics, disease duration or MRI markers of small vessel disease between the three groups. Compared with the Val/Val and Val/Met groups, the Met/Met group showed worse performance in the verbal fluency test and higher levels of plasma NfL. Conclusion: The rs6265 polymorphism of the BDNF gene is associated with semantic language fluency in patients with SIVD. The Met genotype may be a risk factor for cognitive impairment and neuronal injury.

19.
Chin J Traumatol ; 15(1): 42-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22300919

RESUMO

Hip trauma has been a leading cause of death in senile patients for more than a centenary. Although the mortality decreased due to the advanced technique in medication, surgery and nursing, the increasing mortality should not be neglected in elders after orthopedic operation nowadays. Many factors are considered to influence the causes of death after trauma, such as age, gender, personal customs, comorbidities, types of fracture, timing of surgery, procedure, anesthesia, complications, medical treatment, activity of daily living, or even marriage status. This article reviews these causes from the aspects of patient's own factors, iatrogenic factors, medical treatment and other factors and provides some clues for further clinical application according to the recent foreign and domestic researches. According to the present research, it is essential for surgeons to perform a comprehensive estimation for patients suffering from hip trauma.


Assuntos
Causas de Morte , Fraturas do Quadril , Fraturas do Quadril/cirurgia , Humanos , Procedimentos Ortopédicos , Análise de Regressão
20.
Comput Math Methods Med ; 2022: 2914484, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35799673

RESUMO

Objective: Vitamin D is associated with neurological deficits in patients with cerebral infarction. This study uses machine learning to evaluate the prediction model's efficacy of the correlation between vitamin D and neurological deficit in patients with cerebral infarction. Methods: A total of 200 patients with cerebral infarction admitted to the Department of Neurology of our hospital from July 2018 to June 2019 were selected. The patients were randomly divided into a training set (n = 140) and a test set (n = 60) in a 7 : 3 ratio. The prediction model is constructed from the training set's data, and the model's prediction effect was evaluated by test set data. The area under the receiver operator characteristic curve was used to assess the prediction efficiency of models. Results: In the training set, the area under the curve (AUC) of the logistic regression model and XGBoost algorithm model was 0.727 (95% CI: 0.601~0.854) and 0.818 (95% CI: 0.734~0.934), respectively. While in the test set, the AUC of the logistic regression model and XGBoost algorithm model was 0.761 (95% CI: 0.640~0.882) and 0.786 (95% CI: 0.670~0.902), respectively. Conclusion: The prediction model of the correlation between vitamin D and neurological deficit in patients with cerebral infarction based on machine learning has a good prediction efficiency.


Assuntos
Aprendizado de Máquina , Vitamina D , Área Sob a Curva , Infarto Cerebral , Humanos , Modelos Logísticos , Estudos Retrospectivos
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