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1.
Neural Regen Res ; 20(4): 946-959, 2025 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38989930

RESUMEN

Müller glia, as prominent glial cells within the retina, plays a significant role in maintaining retinal homeostasis in both healthy and diseased states. In lower vertebrates like zebrafish, these cells assume responsibility for spontaneous retinal regeneration, wherein endogenous Müller glia undergo proliferation, transform into Müller glia-derived progenitor cells, and subsequently regenerate the entire retina with restored functionality. Conversely, Müller glia in the mouse and human retina exhibit limited neural reprogramming. Müller glia reprogramming is thus a promising strategy for treating neurodegenerative ocular disorders. Müller glia reprogramming in mice has been accomplished with remarkable success, through various technologies. Advancements in molecular, genetic, epigenetic, morphological, and physiological evaluations have made it easier to document and investigate the Müller glia programming process in mice. Nevertheless, there remain issues that hinder improving reprogramming efficiency and maturity. Thus, understanding the reprogramming mechanism is crucial toward exploring factors that will improve Müller glia reprogramming efficiency, and for developing novel Müller glia reprogramming strategies. This review describes recent progress in relatively successful Müller glia reprogramming strategies. It also provides a basis for developing new Müller glia reprogramming strategies in mice, including epigenetic remodeling, metabolic modulation, immune regulation, chemical small-molecules regulation, extracellular matrix remodeling, and cell-cell fusion, to achieve Müller glia reprogramming in mice.

2.
J Youth Adolesc ; 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39289211

RESUMEN

Family resilience is crucial for individual's psychological health. Previous studies explored the protective factors of anxiety at the individual level, with less attention paid to the impact of family interaction from a dyadic perspective. This study utilized the Actor-Partner Interdependence Mediation Model to investigate the relationship between family resilience, emotional flexibility, and anxiety symptoms. A sample of 2144 Chinese parent-adolescent dyads (36% upper grades of primary school, 64% secondary school, 49.39% girls; 70.38% mothers) was recruited. Perceived family resilience was inversely related to anxiety symptoms, directly or indirectly, through the mediation of emotional flexibility at the individual level. At the dyadic level, adolescents' perceived family resilience was significantly associated with parents' anxiety symptoms through their own or parents' emotional flexibility. Parents' perceived family resilience was inversely link to adolescents' anxiety symptoms through parents' emotional flexibility. Parents emotional flexibility also mediated the association between adolescents' perceived family resilience and their anxiety symptoms. These findings contribute to understanding the intricate dynamics of family resilience and psychological outcomes in parent-child relationships under adversity, emphasizing the need for child-centered interventions to improve family members' mental health.

3.
Org Biomol Chem ; 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39283052

RESUMEN

Cleavage of the C-N bond of a secondary amide could provide alternative access to primary amides; however, this strategy remains challenging due to oxidation resistance of the amide. Herein, we employed the cobalt(II)/Oxone catalytic system, one of the advanced oxidation processes (AOPs), to make it available to break the strong C-N bond of various secondary (sulfon)amides, especially those bearing electron-poor or ortho-substituted N-arenes, en route to desirable primary (sulfon)amides. Control experiments showed that it was probably not the generally-considered persulfate anion radical in the cobalt/peroxymonosulfate (Co/PMS) system but the proposed high-valent cobalt-oxo intermediate that should be the major active species for the initial N-H oxidation of N-aryl amides. In the case of N-alkylated secondary amides, the α-C-H bond, rather than the N-H bond, should be oxidized first by both the reactive radicals and high-valent cobalt-oxo species. This work not only establishes an efficient method for removing the N-substituents of secondary amides at low cost, with readily available and eco-friendly reagents, but also demonstrates further synthetic application and provides more insight into intermediates for metal-based AOPs in environmental remediation.

4.
Environ Pollut ; 360: 124679, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39116923

RESUMEN

The Ulva prolifera bloom is considered one of the most serious ecological disasters in the Yellow Sea in the past decade, forming a carbon sink in its source area within a short period but becoming a carbon source at its destination. To explore the effects of different environmental changes on seawater dissolved carbon pools faced by living U. prolifera in its originating area, U. prolifera were cultured in three sets with different light intensity (54, 108, and 162 µmol m-2 s-1), temperature (12, 20, and 28 °C) and nitrate concentration gradients (25, 50, and 100 µmol L-1). The results showed that moderate light (108 µmol m-2 s-1), temperature (20 °C), and continuous addition of exogenous nitrate significantly enhanced the absorption of dissolved inorganic carbon (DIC) in seawater by U. prolifera and most promoted its growth. Under the most suitable environment, the changes in the seawater carbonate system were mainly dominated by biological production and denitrification, with less influence from aerobic respiration. Facing different environmental changes, U. prolifera continuously changed its carbon fixation mode according to tissue δ13C results, with the changes in the concentrations of various components of DIC in seawater, especially the fluctuation of HCO3- and CO2 concentrations. Enhanced light intensity of 108 µmol m-2 s-1 could shift the carbon fixation pathway of U. prolifera towards the C4 pathway compared to temperature and nitrate stimulation. Environmental conditions at the origin determined the amount of dissolved carbon fixed by U. prolifera. Therefore, more attention should be paid to the changes in marine environmental conditions at the origin of U. prolifera, providing a basis for scientific management of U. prolifera.


Asunto(s)
Secuestro de Carbono , Carbono , Agua de Mar , Ulva , Ulva/metabolismo , Agua de Mar/química , Nitratos/análisis , Temperatura , Algas Comestibles
5.
Nat Commun ; 15(1): 7131, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39164277

RESUMEN

Organic nitrates, as effective donors of the signaling molecule nitric oxide, are widely applied in the pharmaceutical industry. However, practical and efficient methods for accessing organic nitrates are still scarce, and achieving high regiocontrol in unactivated alkene difunctionalization remains challenging. Here we present a simple and practical method for highly regioselective halonitrooxylation of unactivated alkenes. The approach utilizes TMSX (X: Cl, Br, or I) and oxybis(aryl-λ3-iodanediyl) dinitrates (OAIDN) as sources of halogen and nitrooxy groups, with 0.5 mol % FeCl3 as the catalyst. Remarkably, high regioselectivity in the halonitrooxylation of aromatic alkenes can be achieved even without any catalyst. This protocol features easy scalability and excellent functional group compatibility, providing a range of ß-halonitrates (127 examples, up to 99% yield, up to >20:1 rr). Notably, 2-iodoethyl nitrate, a potent synthon derived from ethylene, reacts smoothly with a variety of functional units to incorporate the nitrooxy group into the desired molecules.

6.
Nat Commun ; 15(1): 7040, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39147767

RESUMEN

Diagnosing liver lesions is crucial for treatment choices and patient outcomes. This study develops an automatic diagnosis system for liver lesions using multiphase enhanced computed tomography (CT). A total of 4039 patients from six data centers are enrolled to develop Liver Lesion Network (LiLNet). LiLNet identifies focal liver lesions, including hepatocellular carcinoma (HCC), intrahepatic cholangiocarcinoma (ICC), metastatic tumors (MET), focal nodular hyperplasia (FNH), hemangioma (HEM), and cysts (CYST). Validated in four external centers and clinically verified in two hospitals, LiLNet achieves an accuracy (ACC) of 94.7% and an area under the curve (AUC) of 97.2% for benign and malignant tumors. For HCC, ICC, and MET, the ACC is 88.7% with an AUC of 95.6%. For FNH, HEM, and CYST, the ACC is 88.6% with an AUC of 95.9%. LiLNet can aid in clinical diagnosis, especially in regions with a shortage of radiologists.


Asunto(s)
Carcinoma Hepatocelular , Colangiocarcinoma , Aprendizaje Profundo , Hemangioma , Neoplasias Hepáticas , Tomografía Computarizada por Rayos X , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Carcinoma Hepatocelular/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Masculino , Hemangioma/diagnóstico por imagen , Colangiocarcinoma/diagnóstico por imagen , Colangiocarcinoma/patología , Femenino , Hígado/diagnóstico por imagen , Hígado/patología , Persona de Mediana Edad , Hiperplasia Nodular Focal/diagnóstico por imagen , Adulto , Anciano , Área Bajo la Curva , Quistes/diagnóstico por imagen
7.
Adv Sci (Weinh) ; : e2405367, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39207041

RESUMEN

Peritendinous adhesion that forms after tendon injury substantially limits daily life. The pathology of adhesion involves inflammation and the associated proliferation. However, the current studies on this condition are lacking, previous studies reveal that cyclooxygenase-2 (COX2) gene inhibitors have anti-adhesion effects through reducing prostaglandin E2 (PGE2) and the proliferation of fibroblasts, are contrary to the failure in anti-adhesion through deletion of EP4 (prostaglandin E receptor 4) gene in fibroblasts in mice of another study. In this study, single-cell RNA sequencing analysis of human and mouse specimens are combined with eight types of conditional knockout mice and further reveal that deletion of COX2 in myeloid cells and deletion of EP4 gene in sensory nerves decrease adhesion and impair the biomechanical properties of repaired tendons. Furthermore, the COX2 inhibitor parecoxib reduces PGE2 but impairs the biomechanical properties of repaired tendons. Interestingly, PGE2 local treatment improves the biomechanical properties of the repaired tendons. These findings clarify the complex role of PGE2 in peritendinous adhesion formation (PAF) and tendon repair.

8.
Sci Rep ; 14(1): 16939, 2024 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-39043780

RESUMEN

As climate change continues to modify temperature and rainfall patterns, risks from pests and diseases may vary as shifting temperature and moisture conditions affect the life history, activity, and distribution of invertebrates and diseases. The potential consequences of changing climate on pest management strategies must be understood for control measures to adapt to new environmental conditions. The redlegged earth mite (RLEM; Halotydeus destructor [Tucker]) is a major economic pest that attacks pastures and grain crops across southern Australia and is typically controlled by pesticides. TIMERITE® is a management strategy that relies on estimating the optimal timing (the TIMERITE® date) for effective chemical control of RLEM populations in spring. In this study, we assessed the efficacy of control at the TIMERITE® date from 1990 to 2020 across southern Australia using a simulation approach that incorporates historical climatic data and field experimental data on life history, seasonal abundance, and population level pesticide responses. We demonstrate that moisture and temperature conditions affect the life history of RLEM and that changes in the past three decades have gradually diminished the efficacy of the TIMERITE® strategy. Furthermore, we show that by incorporating improved climatic data into predictions and shifting the timing of control to earlier in the year, control outcomes can be improved and are more stable across changing climates. This research emphasises the importance of accounting for dynamic environmental responses when developing and implementing pest management strategies to ensure their long-term effectiveness. Suggested modifications to estimating the TIMERITE® date will help farmers maintain RLEM control outcomes amidst increasingly variable climatic conditions.


Asunto(s)
Cambio Climático , Ácaros , Control de Plagas , Animales , Control de Plagas/métodos , Australia , Temperatura , Estaciones del Año , Plaguicidas
9.
Environ Res ; 260: 119679, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39059622

RESUMEN

Glyphosate, a commonly used organophosphorus herbicide in rice-crayfish cropping regions, may alter regional phosphorus cycle processes while affecting the structure of microbial communities. However, the effects of glyphosate residues on rice-crayfish systems remain unclear. In this study, we assessed the spatial and temporal distribution characteristics of glyphosate and its primary degradation products, as well as the impact mechanisms of glyphosate on microbial communities and the phosphorus cycle in rice-crayfish systems such as paddy fields, breeding ditches and recharge rivers. The detection rates of glyphosate and aminomethylphosphonic acid (AMPA) were 100% in rice-crayfish systems. Concentrations of glyphosate in the water phase and soil/sediment were as high as 0.012 µg/L and 7.480 µg/kg, respectively, and concentrations of AMPA were as high as 17.435 µg/L and 13.200 µg/kg, respectively. Glyphosate concentrations were not affected by rainfall or sampling site, but concentrations of AMPA in the water phase of recharge rivers were affected by rainfall. The glyphosate concentration was significantly and positively correlated with RBG-16-58-14 abundance, and the AMPA concentration was significantly and positively correlated with Actinobacteria and Lysobacter abundance, and negatively correlated with Cyanobacteria abundance (P < 0.05). The highest abundances of phoD, phnK, and ppx genes were found in all soils/sediments. Glyphosate concentration in soil/sediment was significantly and positively correlated with the abundance of phoD gene encoding an organophosphorus-degrading enzyme and ppx gene encoding poly inorganic phosphate (Pi) hydrolase (P < 0.05). In addition, the glyphosate concentration was significantly and positively correlated with the Ca-bonded Pi content (P < 0.05). This implies that glyphosate may promote the production of stable Pi in rice-crayfish systems by increasing the abundance of phoD and ppx genes. The results of this study reveal the impact mechanism of glyphosate on the phosphorus cycle in rice-crayfish systems and provide a basis for the risk assessment of glyphosate.


Asunto(s)
Glicina , Glifosato , Herbicidas , Organofosfonatos , Fósforo , Glicina/análogos & derivados , Glicina/toxicidad , Glicina/análisis , Animales , Fósforo/análisis , Herbicidas/análisis , Organofosfonatos/análisis , Oryza/microbiología , Microbiota/efectos de los fármacos , Contaminantes Químicos del Agua/análisis , Microbiología del Suelo
10.
Sci Total Environ ; 946: 174207, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-38914327

RESUMEN

Di-n-butyl phthalate (DBP) is one of the important phthalates detected commonly in soils and crops, posing serious threat to human health. Pseudochrobactrum sp. XF203 (XF203), a new strain related with DBP biodegradation, was first identified from a natural habitat lacking human disturbance. Genomic analysis coupled with gene expression comparison assay revealed this strain harbors the key aromatic ring-cleaving gene catE203 (encoding catechol 2,3-dioxygenase/C23O) involved DBP biodegradation. Following intermediates identification and enzymatic analysis also indicated a C23O dependent DBP lysis pathway in XF203. The gene directed ribosome engineering was operated and to generate a desirable mutant strain XF203R with highest catE203 gene expression level and strong DBP degrading ability. The X203R removed DBP in soil jointly by reassembling bacterial community. These results demonstrate a great value of XF203R for the practical DBP bioremediation application, highlighting the important role of the key gene-directed ribosome engineering in mining multi-pollutants degrading bacteria from natural habitats where various functional genes are well conserved.


Asunto(s)
Biodegradación Ambiental , Dibutil Ftalato , Ribosomas , Contaminantes del Suelo , Contaminantes del Suelo/metabolismo , Dibutil Ftalato/metabolismo , Ribosomas/metabolismo , Microbiología del Suelo , Expresión Génica , Burkholderiaceae/metabolismo , Burkholderiaceae/genética
11.
Nat Commun ; 15(1): 4919, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38858346

RESUMEN

Chiral 1,2,3-triazoles are highly attractive motifs in various fields. However, achieving catalytic asymmetric click reactions of azides and alkynes for chiral triazole synthesis remains a significant challenge, mainly due to the limited catalytic systems and substrate scope. Herein, we report an enantioselective azidation/click cascade reaction of N-propargyl-ß-ketoamides with a readily available and potent azido transfer reagent via copper catalysis, which affords a variety of chiral 1,2,3-triazoles with up to 99% yield and 95% ee under mild conditions. Notably, chiral 1,5-disubstituted triazoles that have not been accessed by previous asymmetric click reactions are also prepared with good functional group tolerance.

13.
Arch Psychiatr Nurs ; 50: 115-121, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38789223

RESUMEN

OBJECTIVE: The family system is important for children's development. Previous research has demonstrated that some families are able to maintain good adaptability or resilience in the face of stressors. This study aimed to develop the revised Chinese version of the Family Resilience Assessment Scale and examine the psychometric properties of the scale among children disadvantaged in adversity due to family migration. METHODS: A total of 1487 children (47.6 % girls) from disadvantaged families participated in this study, whom completed the revised Chinese version of the Family Resilience Assessment Scale, the Chinese version of the Connor-Davidson Resilience Scale, and the Center for Epidemiologic Studies Depression Scale for Children. RESULTS: (1) Good language equivalency was found (Intraclass Correlation Coefficient = 0.96); (2) Item analysis indicated that the critical ratio values of all 45 items were above 0.30 (p < 0.001), except for 7 items that were dropped from further analysis; (3) The exploratory factor analysis indicated that the best model was four-factor model; (4) The confirmatory factor analysis showed that the four-factor model had good model fit; (5) Family resilience was significantly correlated with personal resilience and depression; (6) The internal consistency reliability of the scale was 0.95. CONCLUSIONS: This study confirmed that the revised Chinese version of the Family Resilience Assessment Scale was a reliable and valid instrument to assess family resilience of Chinese children who are disadvantaged.


Asunto(s)
Psicometría , Resiliencia Psicológica , Poblaciones Vulnerables , Humanos , Psicometría/instrumentación , Femenino , Masculino , Reproducibilidad de los Resultados , Poblaciones Vulnerables/psicología , Niño , Encuestas y Cuestionarios , China , Familia/psicología , Depresión/psicología
14.
Zhen Ci Yan Jiu ; 49(4): 341-348, 2024 Apr 25.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-38649201

RESUMEN

OBJECTIVES: To study the regularity of central response to thermal needle stimulation of "Zusanli" (ST36) at different temperature, and to analyze the temperature difference of central responses. METHODS: Six male C57BL/6j adult mice were used in the present study. For observing activities of neurons in the hindlimb region of left primary somatosensory cortex (S1HL, A/P=0.46 mm, M/L=1.32 mm, D/V=-0.14 mm) by using a fast high-resolution miniature two-photon microscopy (FHIRM-TPM), the mice were anesthetized with 3% isoflurane (inhalation), with its head fixed in a stereotaxic apparatus, then, adeno-associated virus (AAV-hSyn-GCaMP6f-WPRE-hGHpA, for showing intracellular calcium transients in neurons transfected) was injected into the left S1HL region using a micro-syringe after scalp surgical operation. The mice's right ST36 were stimulated using internal thermal needles with the temperature being 43 ℃, or 45 ℃, or 47 ℃, separately. Image J software and MATLAB 2020b software were used to process the image data of neuronal calcium activity (Ca2+ signaling) in the left S1HL region, including the instant maximum calcium peak value (ΔF/F) in 2 s, instant calcium spike frequency in 2 s, short-term calcium peak value (ΔF/F) in 3.5 min, short-term calcium spike frequency in 3.5 min, calcium peak duration in 3.5 min, maximum calcium peak value (ΔF/F) at the 1st , 2nd and 3rd min, and calcium spike frequency at the 1st, 2nd and 3rd min after thermal needle stimulation. RESULTS: In comparison with the normal temperature needle stimulation, the instant intracellular maximum calcium peak value, instant calcium spike frequency, short-term maximum calcium peak value, short-term calcium spike frequency, and calcium peak duration of S1HL neurons in response to 43 ℃, 45 ℃ and 47 ℃ internal thermal needle stimulation of ST36 were significantly increased (P<0.001, P<0.01). Comparison among the 43 ℃, 45 ℃ and 47 ℃ thermal needle stimulation showed that the 45 ℃ thermal needle stimulation was obviously superior to 43 ℃ and 47 ℃ thermal needle stimulation in increasing instant calcium spike frequency, short-term calcium spike frequency and calcium peak duration of S1HL neurons (P<0.001, P<0.01). The 47 ℃ thermal needle stimulation was stronger than 43 ℃ and 45 ℃ thermal needle stimulation in increasing the instant maximum calcium peak value (P<0.001). The maximum calcium peak value was apparently higher (P<0.001) at the 2nd min than that at the 1st and 3rd min after 43 ℃, 45 ℃ and 47 ℃ thermal needle stimulation. No significant differences were found in the short-term maximum calcium peak value among the 3 thermal needle stimulation and in the calcium spike frequency among the 3 time points after 43 ℃, 45 ℃ and 47 ℃ thermal needle stimulation. CONCLUSIONS: S1HL neurons respond to all 43 ℃, 45 ℃ and 47 ℃ thermal needle stimulation of ST36 in mice, while more actively to 45 ℃ thermal needle stimulation.


Asunto(s)
Miembro Posterior , Ratones Endogámicos C57BL , Neuronas , Corteza Somatosensorial , Animales , Ratones , Masculino , Neuronas/fisiología , Corteza Somatosensorial/fisiología , Corteza Somatosensorial/metabolismo , Puntos de Acupuntura , Humanos , Agujas , Calor , Temperatura
15.
iScience ; 27(3): 109229, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38455977

RESUMEN

Current studies on the immune microenvironment of colorectal cancer (CRC) were mostly limited to the tissue level, lacking relevant studies in the peripheral blood, and failed to describe its alterations in the whole process of adenocarcinoma formation, especially of adenoma carcinogenesis. Here, we constructed a large-scale population cohort and used the CyTOF to explore the changes of various immune cell subsets in peripheral blood of CRC. We found monocytes and basophils cells were significantly higher in adenocarcinoma patients. Compared with early-stage CRC, effector CD4+T cells and naive B cells were higher in patients with lymph node metastasis, whereas the basophils were lower. We also performed random forest algorithm and found monocytes play the key role in carcinogenesis. Our study draws a peripheral blood immune cell landscape of the occurrence and development of CRC at the single-cell level and provides a reference for other researchers.

16.
Stem Cell Res Ther ; 15(1): 54, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38414051

RESUMEN

BACKGROUND: Unlike in lower vertebrates, Müller glia (MG) in adult mammalian retinas lack the ability to reprogram into neurons after retinal injury or degeneration and exhibit reactive gliosis instead. Whether a transition in MG cell fate from gliosis to reprogramming would help preserve photoreceptors is still under exploration. METHODS: A mouse model of retinitis pigmentosa (RP) was established using MG cell lineage tracing mice by intraperitoneal injection of sodium iodate (SI). The critical time point for the fate determination of MG gliosis was determined through immunohistochemical staining methods. Then, bulk-RNA and single-cell RNA seq techniques were used to elucidate the changes in RNA transcription of the retina and MG at that time point, and new genes that may determine the fate transition of MG were screened. Finally, the selected gene was specifically overexpressed in MG cells through adeno-associated viruses (AAV) in the mouse RP model. Bulk-RNA seq technique, immunohistochemical staining methods, and visual function testing were used to elucidate and validate the mechanism of new genes function on MG cell fate transition and retinal function. RESULTS: Here, we found the critical time point for MG gliosis fate determination was 3 days post SI injection. Hmga2 was screened out as a candidate regulator for the cell fate transition of MG. After retinal injury caused by SI, the Hmga2 protein is temporarily and lowly expressed in MG cells. Overexpression of Hmga2 in MG down-regulated glial cell related genes and up-regulated photoreceptor related genes. Besides, overexpressing Hmga2 exclusively to MG reduced MG gliosis, made MG obtain cone's marker, and retained visual function in mice with acute retinal injury. CONCLUSION: Our results suggested the unique reprogramming properties of Hmga2 in regulating the fate transition of MG and neuroprotective effects on the retina with acute injury. This work uncovers the reprogramming ability of epigenetic factors in MG.


Asunto(s)
Células Ependimogliales , Retinitis Pigmentosa , Animales , Ratones , Células Ependimogliales/metabolismo , Gliosis/metabolismo , Proteína HMGA2/metabolismo , Retina/metabolismo , Retinitis Pigmentosa/metabolismo , Modelos Animales de Enfermedad , ARN/metabolismo , Neuroglía/metabolismo , Mamíferos
17.
J Hazard Mater ; 462: 132757, 2024 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-37865072

RESUMEN

Accelerated eutrophication in lakes reduces the number of submerged macrophytes and alters the residues of glyphosate and its degradation products. However, the effects of submerged macrophytes on the fate of glyphosate remain unclear. We investigated eight lakes with varying trophic levels along the middle and lower reaches of the Yangtze River in China, of which five lakes contained either glyphosate or aminomethylphosphate (AMPA). Glyphosate and AMPA residues were significantly positively correlated with the trophic levels of lakes (P < 0.01). In lakes, glyphosate is degraded through the AMPA and sarcosine pathways. Eight shared glyphosate-degrading enzymes and genes were observed in different lake sediments, corresponding to 44 degrading microorganisms. Glyphosate concentrations in sediments were significantly higher in lakes with lower abundances of soxA (sarcosine oxidase) and soxB (sarcosine oxidase) (P < 0.05). In the presence of submerged macrophytes, oxalic and malonic acids secreted by the roots of submerged macrophytes increased the abundance of glyphosate-degrading microorganisms containing soxA or soxB (P < 0.05). These results revealed that a decrease in the number of submerged macrophytes in eutrophic lakes may inhibit glyphosate degradation via the sarcosine pathway, leading to a decrease in glyphosate degradation and an increase in glyphosate residues.


Asunto(s)
Lagos , Sarcosina , Lagos/química , Sarcosina-Oxidasa , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico , Exudados y Transudados , China , Eutrofización , Glifosato
18.
PLoS One ; 18(11): e0294345, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37983230

RESUMEN

Civil aviation transport is an important source of global respiratory disease spread due to the closely-spaced environment. In order to reduce the probability of infection of passengers, an improved Wells-Riley model for cabin passenger risk assessment have been given in this work, the cabin ventilation and passenger nose and mouth orientation were considered. The model's effectiveness has been verified with published data. Finally, how the load factor and use of an empty seat scheme are associated with the number of infected people was assessed. The results demonstrated that the number of infected people positively correlates with the passenger load factor, and the most suitable load factor can be determined by controlling the final number of infected people with the condition of the epidemic situation in the departure city. Additionally, infection risk was found to be lower among passengers in window seats than in those in aisle seats and middle seats, and keeping empty seats in the middle or aisle could reduce the cabin average probability of infection by up to 37.47%. Using the model developed here, airlines can determine the optimal load factor threshold and seating arrangement strategy to improve economic benefits and reduce the probability of passenger infection.


Asunto(s)
Aviación , Humanos , Medición de Riesgo , Ventilación , Probabilidad
19.
Mar Pollut Bull ; 196: 115632, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37826908

RESUMEN

Spatial distributions of dissolved and particulate dimethylsulfoxide (DMSOd and DMSOp) were investigated off the northern Antarctic Peninsula during the austral summer of 2018, an ecologically and climatically important region of the world. In the upper waters, DMSOd was concentrated in the ice-melt zone because DMSO functions physiologically as an intracellular osmolyte and cryoprotectant. DMSOd concentrations had a weak positive correlation with temperature but a negative correlation with nutrients. This highlighted the importance of temperature-dependent biological activities and photolysis in DMSOd production and the important role of the intracellular antioxidation system in phytoplankton cells. The decrease of average DMSOp:Chl-a ratios in upper waters from west to east, along with decreasing temperatures and increasing diatoms proportions in the phytoplankton, illustrates how seawater DMSO production capacities depend on ambient temperatures and the composition of phytoplankton assemblages. DMSOp were accumulated in deep waters through bio-debris accumulation and microbial activity.


Asunto(s)
Dimetilsulfóxido , Agua de Mar , Regiones Antárticas , Estaciones del Año , Fitoplancton/fisiología
20.
Math Biosci Eng ; 20(8): 14846-14865, 2023 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-37679162

RESUMEN

In this paper, the complete synchronization and Mittag-Leffler synchronization problems of a kind of coupled fractional-order neural networks with time-varying delays are introduced and studied. First, the sufficient conditions for a controlled system to reach complete synchronization are established by using the Kronecker product technique and Lyapunov direct method under pinning control. Here the pinning controller only needs to control part of the nodes, which can save more resources. To make the system achieve complete synchronization, only the error system is stable. Next, a new adaptive feedback controller is designed, which combines the Razumikhin-type method and Mittag-Leffler stability theory to make the controlled system realize Mittag-Leffler synchronization. The controller has time delays, and the calculation can be simplified by constructing an appropriate auxiliary function. Finally, two numerical examples are given. The simulation process shows that the conditions of the main theorems are not difficult to obtain, and the simulation results confirm the feasibility of the theorems.

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