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1.
Soft Matter ; 16(12): 2928-2932, 2020 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-32154538

RESUMEN

A diversified and biocompatible rhythmic deformation (RD) system is successfully fabricated by coupling a heterogeneous hydrogel with a pH oscillator. By tailoring the geometry of the building blocks, a heterogeneous hydrogel actuator with diversity could be easily constructed through interfacial adhesion. Moreover, the RD behaviour can be regulated by the system temperature and actuator shape.

2.
Molecules ; 25(15)2020 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-32722108

RESUMEN

Loquat fruit is one of the most perishable fruits in China, and has a very limited shelf life because of mechanical injury and microbial decay. Due to an increasing concern about human health and environmental security, antagonistic microorganisms have been a potential alternative for fungicides to control postharvest diseases. In this work, the antifungal effect of volatile organic compounds (VOCs) produced by Bacillus methylotrophicus BCN2 and Bacillus thuringiensis BCN10 against five postharvest pathogens isolated from loquat fruit, Fusarium oxysporum, Botryosphaeria sp., Trichoderma atroviride, Colletotrichum gloeosporioides, and Penicillium expansum were evaluated by in vitro and in vivo experiments. As a result, the VOCs released by BCN2 and BCN10 were able to suppress the mycelial growth of all targeted pathogens according to inhibition ratio in the double petri-dish assay as well as disease incidence and disease diameter on loquat fruits. The main volatile compounds were identified by solid-phase microextraction (SPME)-gas chromatography. These VOCs produced by the two strains played complementary roles in controlling these five molds and enabled loquat fruits to keep fresh for ten days, significantly. This research will provide a theoretic foundation and technical support for exploring the functional components of VOCs applicable in loquat fruit preservation.


Asunto(s)
Antifúngicos/farmacología , Bacillus thuringiensis/química , Bacillus/química , Eriobotrya/microbiología , Compuestos Orgánicos Volátiles/farmacología , Antifúngicos/química , Ascomicetos/efectos de los fármacos , Ascomicetos/crecimiento & desarrollo , Cromatografía de Gases , Colletotrichum/efectos de los fármacos , Colletotrichum/crecimiento & desarrollo , Hypocreales/efectos de los fármacos , Hypocreales/crecimiento & desarrollo , Penicillium/efectos de los fármacos , Penicillium/crecimiento & desarrollo , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Microextracción en Fase Sólida , Compuestos Orgánicos Volátiles/química
3.
Phytopathology ; 106(2): 192-201, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26506459

RESUMEN

Puccinia striiformis f. sp. tritici is the causal pathogen of interregional epidemics of wheat stripe rust in China via long-distance migration. Gansu Province serves as putative inoculum center providing oversummering inoculum, while Sichuan Basin area serves as a region providing huge amounts of overwintering inoculum. Thus, the relationship between these two regions in population exchange and migration become important in prediction of interregional epidemics. In this study, we compared the population genetic structure and race composition between Gansu and Sichuan Basin populations to infer their migration relationships. A total of 526 isolates, spanning 3 years, were genotyped using eight pairs of amplified fragment length polymorphism markers, and a subset of 98 isolates were inoculated onto 19 Chinese differentials to perform the race analysis. Twenty-three common races and 26 shared genotypes supplied molecular evidence for migration between Gansu and Sichuan Basin populations. Bayesian assignment and principal component analysis revealed that the genetic group assignment of the Sichuan Basin populations (10SB and 11SB) changed in the spring to align with the fall Gansu populations in the prior seasons (09GS and 10GS), which indicated an asymmetric migration from Gansu Province to the Sichuan Basin area. The linkage disequilibrium and the parsimony tree length permutation test revealed a strong annual recombination signal in the Gansu populations and an inconsistent signal in the Sichuan Basin populations.


Asunto(s)
Basidiomycota/genética , Genética de Población , Enfermedades de las Plantas/microbiología , Polimorfismo Genético/genética , Triticum/microbiología , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Basidiomycota/patogenicidad , Basidiomycota/fisiología , China , ADN de Hongos/genética , Marcadores Genéticos/genética , Estructuras Genéticas , Genotipo , Geografía , Desequilibrio de Ligamiento , Recombinación Genética , Virulencia
4.
Plant Dis ; 99(12): 1764-1774, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30699507

RESUMEN

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the most important fungal diseases of wheat in China. Xinjiang, Qinghai, and Gansu Provinces, located in the northwest of China, are the key regions for interregional epidemics of wheat stripe rust due to their geographic as well as crop-planting features, in relation to pathogen's life cycle, reproduction, and population genetics. To study the population genetic structures of the pathogen in these areas, 217 isolates of P. striiformis f. sp. tritici were collected from different geographic locations at various elevations in the three provinces. The amplified fragment length polymorphism (AFLP) genotypes and virulence phenotypes were analyzed for Xinjiang, Qinghai, and Gansu populations. Frequent genotypic exchanges between Xinjiang and Qinghai and between Qinghai and Gansu populations were detected, demonstrating that the populations of Xinjiang and Gansu may not be completely isolated. Genotypic diversity in Gansu Province was much higher than that in Xinjiang or Qinghai Province. The Xinjiang population was genetically closer to the Qinghai population than to the Gansu population. The race dynamic patterns in Qinghai were consistent with those in Gansu but the similar component pattern of the race dynamics in Xinjiang appeared late, following those in Gansu and other interior epidemic regions of China. No significant correlation between the AFLP genetic distance and the virulence distance in the Xinjiang, Qinghai, and Gansu populations was determined. A possible recombination signature of the pathogen population was detected in Gansu population and some subpopulations in Qinghai but not in Xinjiang population.

5.
Opt Express ; 22(3): 3557-63, 2014 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-24663645

RESUMEN

A two-in-one Faraday rotator mirror was presented, which functions as two independent Faraday rotation mirrors with a single device. With the introduction of a reflection lens as substitution of the mirror in traditional structure, this device is characterized by exemption of active optical alignment for the designers and manufacturers of Faraday rotator mirrors. A sample was fabricated by passive mechanical assembly. The insertion loss was measured as 0.46 dB/0.50 dB for the two independent ports, respectively.

6.
Int J Mol Sci ; 15(11): 19355-68, 2014 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-25347274

RESUMEN

Acute lung injury (ALI) and its severe manifestation of acute respiratory distress syndrome (ARDS) are well-known illnesses. Uncontrolled and self-amplified pulmonary inflammation lies at the center of the pathology of this disease. Emodin, the bio-active coxund of herb Radix rhizoma Rhei, shows potent anti-inflammatory properties through inactivation of nuclear factor-κB (NF-κB). The aim of this study was to evaluate the effect of emodin on lipopolysaccharide (LPS)-induced ALI in mice, and its potential bio-mechanism. In our study, BALB/c mice were stimulated with LPS to induce ALI. After 72 h of LPS stimulation, pulmonary pathological changes, lung injury scores, pulmonary edema, myeloperoxidase (MPO) activity, total cells, neutrophils, macrophages, TNF-α, IL-6 and IL-1ß in bronchoalveolar lavage fluid (BALF), and MCP-1 and E-selectin expression were notably attenuated by emodin in mice. Meanwhile, our data also revealed that emodin significantly inhibited the LPS-enhanced the phosphorylation of NF-κB p65 and NF-κB p65 DNA binding activity in lung. Our data indicates that emodin potently inhibits LPS-induced pulmonary inflammation, pulmonary edema and MCP-1 and E-selectin expression, and that these effects were very likely mediated by inactivation of NF-κB in mice. These results suggest a therapeutic potential of emodin as an anti-inflammatory agent for ALI/ARDS treatment.


Asunto(s)
Lesión Pulmonar Aguda/metabolismo , Emodina/farmacología , FN-kappa B/metabolismo , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/tratamiento farmacológico , Lesión Pulmonar Aguda/genética , Lesión Pulmonar Aguda/patología , Animales , Líquido del Lavado Bronquioalveolar/química , Líquido del Lavado Bronquioalveolar/citología , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Selectina E/genética , Selectina E/metabolismo , Emodina/administración & dosificación , Activación Enzimática/efectos de los fármacos , Expresión Génica , Mediadores de Inflamación/metabolismo , Lipopolisacáridos/efectos adversos , Masculino , Ratones , Peroxidasa/metabolismo , Neumonía/tratamiento farmacológico , Neumonía/metabolismo , Neumonía/patología , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/farmacología , Edema Pulmonar/tratamiento farmacológico , Edema Pulmonar/metabolismo , Edema Pulmonar/patología , Transducción de Señal/efectos de los fármacos
7.
Molecules ; 19(1): 1344-52, 2014 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-24451253

RESUMEN

Barnidipine hydrochloride is a long term dihydropyridine calcium channel blocker used for the treatment of hypertension. During the process development of barnidipine hydrochloride, four barnidipine impurities were detected by high-performance liquid chromatography (HPLC) with an ordinary column (Agilent ZORBAX Eclipse XDB-C18, 150 mm×4.6 mm, 5 µm). All these impurities were identified, synthesized, and subsequently characterized by their respective spectral data (MS, 1H-NMR, and 13C-NMR). The identification of these impurities should be useful for quality control in the manufacture of barnidipine.


Asunto(s)
Antihipertensivos/síntesis química , Antihipertensivos/farmacología , Nifedipino/análogos & derivados , Bloqueadores de los Canales de Calcio/química , Bloqueadores de los Canales de Calcio/farmacología , Contaminación de Medicamentos , Estructura Molecular , Nifedipino/síntesis química , Nifedipino/farmacología , Resonancia Magnética Nuclear Biomolecular
8.
RSC Adv ; 14(16): 10905-10919, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38577425

RESUMEN

Nitrate-nitrogen pertains to the nitrogen component of the overall nitrate present in a given sample in order to reduce nitrate nitrogen pollution in water, nitrate nitrogen removal methods based on iron-carbon micro-electrolysis have become a key research focus. The process and mechanism of nitrate nitrogen removal by microbial coupling was comprehensively explored in a novel iron-carbon micro-electrolysis (ICME) system. In order to establish the transformation pathway of nitrate nitrogen in water, the transformation paths of nitrate nitrogen in water before and after coupling microorganisms in three groups of continuous flow reaction devices, namely sponge iron (s-Fe0), sponge iron + biochar (s-Fe0/BC) and sponge iron + biochar + manganese sand (s-Fe0/BC/MS), were studied. The morphology and composition changes of sponge iron were analyzed by means of characterization, and the microbial population changes in the three groups were analyzed by high-throughput sequencing. Results showed that the nitrate conversion rate in the s-Fe0, s-Fe0/BC and s-Fe0/BC/MS systems reached 99.48%, 99.57% and 99.36%, respectively, with corresponding ammonia nitrogen generation, rates of 3.77%, 9.34% and 11.24% and nitrogen generation rates of 95.71%, 90.23% and 88.12%. Scanning electron microscopy imaging showed that in the s-Fe0/BC and s-Fe0/BC/MS systems the surface of sponge iron was highly corroded, with granular substances in the corrosion product clusters. X-ray photoelectron spectroscopy analysis found that the relative contents of Fe2O3 in the surface oxides of sponge iron after microbial coupling were 38.02% and 71.27% in the s-Fe0/BC and s-Fe0/BC/MS systems, while the relative Fe3O4 contents were 61.98% and 28.72%, respectively. Microbial high-throughput sequencing analysis revealed that the Chao and Ace index values in the s-Fe0 system were 871.89 and 880.78, while in the s-Fe0/BC system they were 1012.05 and 1017.29, and in the s-Fe0/BC/MS system were 1241.09 and 1198.29, respectively. The relative proportion of Thauera in the s-Fe0, s-Fe0/BC, and s-Fe0/BC/MS systems was 16.76%,14.25% and 10.01%, while the proportion of Acetoanaerobium was 15.36%, 13.27% and 11.11%, and the proportion of Chloroflexi was 0%, 1.11% and 2.18%, respectively. Furthermore, FAPROTAX function annotation found that the expression levels of chemoheterotrophs in the s-Fe0, s-Fe0/BC and s-Fe0/BC/MS systems were 43 316 OTU, 37 289 OTU and 34 205 OTU, while nitrate respiration expression levels were 16 230 OTU, 15 483 OTU and 9149 OTU, with nitrogen respiration expression levels of 16 328 OTU, 15 493 OTU and 9154 OTU, respectively. These findings suggest that nitrate is converted into nitrogen gas and ammonia nitrogen through the actions of the coupled system of sponge iron/biochar/manganese sand and microorganisms. The catalytic effect of MnO2 promotes the conversion of Fe2+ to Fe3+, generating more electrons, allowing denitrifying bacteria to reduce more nitrate nitrogen, effectively coupling the manganese-catalyzed ICME reaction and microbial denitrification. The micro-electrolysis system and the addition of manganese sand enhanced biodiversity within the s-Fe0/BC/MS system. The heterotrophic bacteria Thauera and Acetoanaerobium were the dominant microorganisms in all three systems, although the micro-electrolysis system with added manganese sand significantly reduced the proportion of facultative bacteria Thauera and Acetoanaerobium and promoted the growth of autotrophic Chloroflexi bacteria. The ecological functions of the three systems were mainly nitrate respiration and nitrogen respiration. By comparing the expression levels of nitrate respiration and nitrogen respiration in s-Fe0/BC and s-Fe0/BC/MS systems, it can be seen that the addition of manganese sand reduced microbial activity.

9.
Front Public Health ; 12: 1305924, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38299072

RESUMEN

Objective: As two line trends - aging disability and disability aging - continue to emerge, hearing disability is becoming increasingly prevalent among older adults in china. This study aimed to investigate the incidence of hearing disability among older adults and identify the various factors contributing to its development. Methods: In this matched nested case-control study, data from the China Health and Retirement Longitudinal Study from 2011 to 2018 were analyzed. A total of 4,523 older adults were recruited from a national sample database, of which 1,094 individuals were eligible for inclusion in the hearing disability cohort, while 3,429 older adults who had not been diagnosed with hearing disability were considered non-hearing disability controls. Hearing disability was assessed by a self-reported question. These controls were matched to hearing disability cases in a 1:1 ratio based on age and sex. The logistic regression models were used to find out various factors of hearing disability in the target population. Results: Totally 1,094 individuals (24.14%) developed hearing disability during the follow-up period. After 1:1 matching, 2,182 subjects were included in the study, with 1,091 cases in the case group. Factors that influenced the incidence of hearing disability in older adults included annual per capita household income (OR = 0.985, p = 0.003), cognitive function (OR = 0.982, p = 0.015), depression level (OR = 1.027, p < 0.001), somatic mobility (OR = 0.946, p = 0.007), history of kidney disease (OR = 1.659, p < 0.001), history of asthma (OR = 1.527, p = 0.008), history of accidental injuries (OR = 1.348, p = 0.015), whether there is a place for recreational and fitness activities in the community (OR = 0.672, p < 0.001), and whether there is a health service center/health center in the community (OR = 0.882, p = 0.006). Conclusion: The incidence of hearing disabilities among older adults in China is high. The protective and risk factors that contribute to the incidence of disability should be fully considered in the care of older adults.


Asunto(s)
Envejecimiento , Audición , Humanos , Anciano , Estudios Longitudinales , Estudios de Casos y Controles , China/epidemiología
10.
J Multidiscip Healthc ; 17: 2331-2350, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38770173

RESUMEN

Purpose: To conducted a scoping review of care needs of older adults with disabilities at home and in the community and provide a comprehensive understanding of the essential needs of older adults with disabilities. Methods: Eight databases were searched for relevant Chinese and English studies (supplemented by retrospective references of the included studies) from the establishment of the database to February 13, 2023. An thematic synthesis approach was used to qualitatively integrate the retrieved studies and identify need-related themes. Results: A total of 6239 studies were retrieved, 2557 were de-weighted and excluded, and 56 were obtained after the double screening. Studies were from 11 countries. Thirty-three studies used a self-prepared survey instrument to investigate needs, and the other research tools commonly used were secondary databases and the Long-Term Care Needs of the Disabled Scale. A total of 78 specific need items were identified and summarized into three need themes based on the ICF framework: physical functioning needs, activity and participation needs, and environment needs. Conclusion: The complex physical and mental health conditions faced by older adults with disabilities result in multifaceted, integrated needs that are difficult to identify and meet. Current research on older adults with disabilities is limited to common care. Future research should focus on the specificities of the older disabled population and understand the diverse care needs of people with disabilities in order to better target care services for this group. Policymakers should formulate more operational and strategic measures based on the actual needs of older adults with disabilities to expand the coverage of services and to pinpoint care services.

11.
Bone Res ; 12(1): 18, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38514644

RESUMEN

The autonomic nervous system plays a crucial role in regulating bone metabolism, with sympathetic activation stimulating bone resorption and inhibiting bone formation. We found that fractures lead to increased sympathetic tone, enhanced osteoclast resorption, decreased osteoblast formation, and thus hastened systemic bone loss in ovariectomized (OVX) mice. However, the combined administration of parathyroid hormone (PTH) and the ß-receptor blocker propranolol dramatically promoted systemic bone formation and osteoporotic fracture healing in OVX mice. The effect of this treatment is superior to that of treatment with PTH or propranolol alone. In vitro, the sympathetic neurotransmitter norepinephrine (NE) suppressed PTH-induced osteoblast differentiation and mineralization, which was rescued by propranolol. Moreover, NE decreased the PTH-induced expression of Runx2 but enhanced the expression of Rankl and the effect of PTH-stimulated osteoblasts on osteoclastic differentiation, whereas these effects were reversed by propranolol. Furthermore, PTH increased the expression of the circadian clock gene Bmal1, which was inhibited by NE-ßAR signaling. Bmal1 knockdown blocked the rescue effect of propranolol on the NE-induced decrease in PTH-stimulated osteoblast differentiation. Taken together, these results suggest that propranolol enhances the anabolic effect of PTH in preventing systemic bone loss following osteoporotic fracture by blocking the negative effects of sympathetic signaling on PTH anabolism.


Asunto(s)
Anabolizantes , Resorción Ósea , Fracturas Osteoporóticas , Ratones , Animales , Hormona Paratiroidea/farmacología , Anabolizantes/farmacología , Fracturas Osteoporóticas/tratamiento farmacológico , Propranolol/farmacología , Factores de Transcripción ARNTL , Resorción Ósea/tratamiento farmacológico , Antagonistas Adrenérgicos beta/farmacología
12.
Plant Dis ; 97(4): 501-509, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30722230

RESUMEN

Wheat stripe rust, caused by the fungal pathogen Puccinia striiformis f. sp. tritici, is one of the most destructive plant diseases in China. Gansu and Ningxia Provinces are considered to be the key areas for over-summering of this pathogen in China. In this study, 283 P. striiformis f. sp. tritici isolates were collected in these two provinces. Amplified fragment length polymorphism (AFLP) was used to analyze the population genetics and to infer the chance of population exchanges between different geographic locations and seasons. The genotypic diversity of the Gansu population (0.514) was slightly higher than that of the Ningxia population (0.489). The occurrence of frequent population exchanges between these two regions was observed, showing that 40 AFLP genotypes were shared by the populations of the two provinces. Gene flow between these two regions in autumn and spring subpopulations was also detected. The genotype distribution in three populations of Ningxia from opposite sides of the Liupan Mountains revealed possible significant effects of the mountains on limiting gene flow and population exchange. Phylogenetic analysis confirmed the possibility of recombination in some of the studied subpopulations in both provinces.

13.
Sci Total Environ ; 863: 160855, 2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36535485

RESUMEN

It is imperative to solve the problem of endogenous phosphorus (P) release from sediments in the governance of natural water bodies. Deciphering P migration and transformation patterns that are coupled to iron (Fe) and sulfur (S) cycling at the sediment-water interface (SWI) is the key to understanding the mechanisms underlying endogenous P release. In the present study, we deployed diffusive gradients in thin films (DGT) probes in situ at the SWI in Fuyang River, Hebei Province, China. When the probes were retrieved, the surrounding sediments were synchronously sampled. We analyzed the longitudinal spatiotemporal distribution of Fe, S, and P at the SWI. We also explored how functional bacterial community diversity was associated with the coupling reactions of Fe, S, and P as well as endogenous P release from sediments at the functional gene level. The results showed that labile Fe, S, and P occurred at low concentrations in sediments 0-2 cm below the SWI, while they were enriched in sediments at depths of 4-8 cm. The longitudinal distribution of different labile elements exhibited greater differences between October and February than regional differences, with higher concentrations at downstream locations than upstream locations. In February, Fe/Al-bound P and sulfide (S2-) concentrations increased in sediments compared with those in October owing to an increase in the relative abundances of dominant genera among P-mineralizing bacteria and sulfate-reducing bacteria. As a result, Fe in Fe-bound P precipitated as FeS2, which induced P remobilization and release into the overlying water. The spatiotemporal distribution patterns of functional genes related to P (phoD and ppk) and S (aprA) transformation were consistent with those of labile P and S, which strongly suggests that microorganisms played a role in driving and regulating the coupled cycling of P and S at the SWI.


Asunto(s)
Contaminantes Químicos del Agua , Agua , Fósforo/análisis , Hierro/análisis , Sedimentos Geológicos , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Azufre , China
14.
Water Res ; 245: 120647, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37738938

RESUMEN

Deep reservoirs vary in their hydrostatic pressure owing to artificial water level control. The potential migration of phosphorus (P) in reservoir sediments raises the risk of harmful algal blooms. To ascertain the mechanisms of endogenous P release in reservoirs, we characterised aquatic microbial communities associated with coupled iron (Fe), P and sulphur (S) cycling at the sediment-water interface. The responses of microbial communities to hydrostatic pressures of 0.2-0.7 mega pascals (MPa; that is, micro-pressures) were investigated through a 30-day simulation experiment. Our findings unravelled a potential mechanism that micro-pressure enhanced the solubilisation of Fe/aluminium (Al)-bound P caused by microbially-driven sulphate reduction, leading to endogenous P release in the deep reservoir. Although the vertical distribution of labile Fe was not affected by pressure changes, we did observe Fe resupply at sediment depths of 2-5 cm. Metagenomic analysis revealed increased abundances of functional genes for P mineralisation (phoD, phoA), P solubilisation (pqqC, ppx-gppA) and sulphate reduction (cysD, cysC) in sediments subjected to micro-pressure, which contrasted with the pattern of S oxidation gene (soxB). There was a tight connection between P and S cycling-related microbial communities, based on significant positive correlations between labile element (P and S) concentrations and functional gene (phoD, cysD) abundances. This provided strong support that Fe-P-S coupling processes were governed by micro-pressure through modulation of P and S cycling-related microbial functions. Key taxa involved in P and S cycling (for example, Bradyrhizobium, Methyloceanibacter) positively responded to micro-pressure and as such, indirectly drove P release from sediments by facilitating P mineralisation and solubilisation coupled with sulphate reduction.


Asunto(s)
Fósforo , Contaminantes Químicos del Agua , Fósforo/análisis , Fosfatos/análisis , Contaminantes Químicos del Agua/análisis , Sedimentos Geológicos/análisis , Monitoreo del Ambiente , Agua/análisis , Sulfatos
15.
Environ Sci Pollut Res Int ; 30(17): 50649-50660, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36800085

RESUMEN

The effect of stormwater runoff on dissolved organic matter (DOM) in rivers is one of the central topics in water environment research. Jiujiang is one of the first cities established in the green development demonstration zone of the Yangtze River Economic Belt (Jiangxi Province, China). Three-dimensional excitation-emission matrix fluorescence with parallel factor analysis (3DEEM-PARAFAC) and ultraviolet-visible (UV-Vis) spectroscopy were used to explore the effects of runoff on organic matter in Shili River (Jiujiang, Jiangxi Province, China). The results show that the runoff led to an increase of some critical pollutants and DOM concentrations, especially in the middle reaches of the river. The concentration and relative molecular weight of DOM in water increased as a result of runoff. Three humic-like (C1-C3) and two protein-like (C4 and C5) components of DOM were identified using the PARAFAC model. The sources of the three humic-like components (C1, C2, C3) were consistent, unlike those of the protein-like component C4. Compared with the pre-rainfall period, the content of humus compounds flowing into the river through the early rainwater runoff was lower, which caused the relative content and proportion of humic substances little change and protein-like species increasing. The DOM mainly derived from autochthonous sources, and runoff had limited effect on its characteristics. Jiujiang is a key demonstration city for Yangtze River conservation. Rainwater runoff is one of the pollution sources of urban rivers, which leads to the deterioration of water quality and influences the distribution characteristics of DOM in water bodies. The PARAFAC components could adequately represent different indicators and sources of DOM in urban rivers, providing an important reference for urban river management.


Asunto(s)
Materia Orgánica Disuelta , Ríos , Ríos/química , Espectrometría de Fluorescencia , Calidad del Agua , China , Sustancias Húmicas/análisis , Análisis Factorial
16.
Huan Jing Ke Xue ; 44(11): 6248-6256, 2023 Nov 08.
Artículo en Zh | MEDLINE | ID: mdl-37973107

RESUMEN

In field conditions, a micro-aerobic layer with 1 cm thickness exists on the surface layer of paddy soil owing to the diffusion of dissolved oxygen via flooding water. However, the particularity of carbon and nitrogen transformation in this specific soil layer is not clear. A typical subtropical paddy soil was collected and incubated with13C-labelled rice straw for 100 days. The responses of exogenous fresh organic carbon(13C-rice straw) and original soil organic carbon mineralization to nitrogen fertilizer addition[(NH4)2SO4]in the micro-aerobic layer(0-1 cm) and anaerobic layer(1-5 cm) of paddy soil and their microbial processes were analyzed based on the analysis of 13C incorporation into phospholipid fatty acid(13C-PLFAs). Nitrogen addition promoted the total CO2 and 13C-CO2 emission from paddy soil by 11.4% and 12.3%, respectively. At the end of incubation, with the addition of nitrogen, the total soil organic carbon (SOC) and13C-recovery rate from rice straw in the anaerobic layer were 2.4% and 9.2% lower than those in the corresponding micro-aerobic layer, respectively. At the early stage(5 days), nitrogen addition increased the total microbial PLFAs in the anaerobic layer with a consistent response of bacterial and fungal PLFAs. However, there was no significant effect from nitrogen on microbial abundance in the micro-aerobic layer. Nitrogen addition had no significant impact on the abundance of total 13C-PLFAs in the micro-aerobic and anaerobic layers, but the abundance of 13C-PLFAs for bacteria and fungi in the micro-aerobic layer was decreased dramatically. At the late stage(100 days), the effect of nitrogen addition on microbial PLFAs was consistent with that at the early stage. The abundances of total, bacterial, and fungal 13C-PLFAs were remarkably increased in the anaerobic layer. However, the abundance of 13C-PLFAs in the micro-aerobic layer showed no significant response to nitrogen addition. During the incubation, the content of NH4+-N in the anaerobic soil layer was higher than that in the micro-aerobic soil layer. This indicates that nitrogen addition increased microbial activity in the anaerobic soil layer caused by the higher NH4+-N concentration, as majority of microorganisms preferred to use NH4+-N. Consequently, the microbial utilization and decomposition of organic carbon in the anaerobic soil layer were accelerated. By contrast, richer available N existed in the form of NO3--N in the micro-aerobic soil layer owing to the ammoxidation process. Thus, the shortage of NO3--N preference microorganisms in the paddy soil environment prohibited the microbial metabolism of organic carbon in the micro-aerobic layer. As a whole, nitrogen fertilization enhanced organic carbon loss via microbial mineralization in paddy soil with a weaker effect in the micro-aerobic layer than that in the anaerobic layer, indicating the limited microbial metabolic activity in the surface micro-aerobic layer could protect the organic carbon stabilization in paddy soil. This study emphasizes the heterogeneity of paddy soil and its significant particularity of carbon and nitrogen transformation in micro-aerobic layers. Consequently, this study has implications for optimizing the forms and method for the application of nitrogen fertilizer in paddy cropping systems.


Asunto(s)
Oryza , Suelo , Carbono/análisis , Agricultura/métodos , Nitrógeno/análisis , Fertilizantes/análisis , Anaerobiosis , Dióxido de Carbono/análisis , Microbiología del Suelo , Bacterias
17.
Int J Surg ; 109(7): 1910-1918, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37133988

RESUMEN

BACKGROUND: Osteoporotic vertebral fractures cause pain and disability, which result in a heavy socioeconomic burden. However, the incidence and cost of vertebral fractures in China are unknown. We aimed to assess the incidence and cost of clinically recognized vertebral fractures among people aged 50 years and older in China from 2013 to 2017. MATERIALS AND METHODS: This population-based cohort study was conducted by using Urban Employee Basic Medical Insurance (UEBMI) and Urban Resident Basic Medical Insurance (URBMI) data in China from 2013 to 2017, which covered more than 95% of the Chinese population in urban areas. Vertebral fractures were identified by the primary diagnosis (i.e. International Classification of Diseases code or text of diagnosis) in UEBMI and URBMI. The incidence and medical cost of these clinically recognized vertebral fractures in urban China were calculated. RESULTS: A total of 271 981 vertebral fractures (186 428, 68.5% females and 85 553, 31.5% males) were identified, with a mean age of 70.26 years. The incidence of vertebral fractures among patients aged 50 years and over in China increased ~1.79-fold during the 5 years, from 85.21 per 100 000 person-years in 2013 to 152.13 per 100 000 person-years in 2017. Medical costs for vertebral fractures increased from US$92.74 million in 2013 to US$505.3 million in 2017. Annual costs per vertebral fracture case increased from US$3.54 thousand in 2013 to US$5.35 thousand in 2017. CONCLUSION: The dramatic increase in the incidence and cost of clinically recognized vertebral fractures among patients aged 50 and over in urban China implies that more attention should be given to the management of osteoporosis to prevent osteoporotic fractures.


Asunto(s)
Fracturas de Cadera , Fracturas Osteoporóticas , Fracturas de la Columna Vertebral , Masculino , Femenino , Humanos , Persona de Mediana Edad , Anciano , Fracturas de la Columna Vertebral/epidemiología , Estudios de Cohortes , Incidencia , China/epidemiología
19.
ACS Omega ; 7(7): 5646-5656, 2022 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-35224326

RESUMEN

The temperature/pH dual-responsive gel spheres were prepared by orthogonal experiments and response surface methodology, and finally, the optimal synthesis conditions were obtained by a composite score, including swelling, mechanical properties, mass transfer properties, and so forth. The results showed that a sodium alginate concentration of 3% (w/v), CaCl2 concentration of 2% (w/v), gelling time of 40 h, drop height of 14 cm, NaCl concentration of 0.6% (w/v), N-isopropylacrylamide concentration of 0.03% (w/v), and acrylic acid concentration of 4.06% (w/v) were optimal synthesis conditions. The environmental change tolerance experiments showed that the nitrogen removal of the dual-response nitrifying gel spheres was better than the domesticated sludge at low temperatures (4 °C) and in alkaline (pH 9 and 10) conditions. The as-obtained gel spheres can respond intelligently to the changes in ambient temperature and pH. It is hoped that this study will provide technical parameters for the development and application of microbial immobilization carriers.

20.
Medicine (Baltimore) ; 101(40): e29999, 2022 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-36221346

RESUMEN

BACKGROUND: To compare the effects of thermal softening of double-lumen endotracheal tubes (DLT) at different temperatures during fiberoptic bronchoscopy (FOB)-guided intubation. METHODS: We randomly divided 144 patients undergoing thoracic surgery into 4 groups as follows: T1 (T = 24 ± 1°C, n = 36), T2 (T = 36 ± 1°C, n = 36), T3 (T = 40 ± 1°C, n = 36), and T4 (T = 48 ± 1°C, n = 36). All groups underwent FOB-guided double-lumen endotracheal intubation and positioning. We recorded the duration of positioning and intubation using DLT, intubation resistance (IR), the success rate of the first attempt at endotracheal intubation, and the incidence of postoperative vocal cord injury and hoarseness. RESULTS: The time to intubation was longer in the T1 group than that in the T2, T3, and T4 groups (P < .05). The time for positioning was longer in the T4 group than that in the T1, T2, and T3 groups (P < .05). IR was lower in the T3 and T4 groups than those in T1 and T2 groups (P < .05). The success rate of the first attempt at endotracheal intubation was higher in the T2, T3, and T4 groups than that in the T1 group (P < .05). Postoperative glottic injury and hoarseness were higher in the T1 and T2 groups than those in the T3 and T4 groups (P < .05). CONCLUSION: A thermally softened DLT shortened the time to intubation, reduced the IR, improved the success rate of the first attempt at endotracheal intubation, and lowered the incidence of postoperative glottic injury and hoarseness. The optimal tube temperature for FOB-guided intubation of thermally softened DLT was 40 ± 1°C.


Asunto(s)
Broncoscopía , Intubación Intratraqueal , Broncoscopios , Broncoscopía/efectos adversos , Broncoscopía/instrumentación , Ronquera/epidemiología , Humanos , Intubación Intratraqueal/efectos adversos , Intubación Intratraqueal/métodos , Temperatura
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