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1.
Small ; : e2400756, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38709225

RESUMEN

The direct application of liquid marbles in electromagnetic wave (EMW) absorption is challenging due to their poor stability, susceptibility to gravitational collapse, and shaping difficulties. To address this issue, a novel strategy is proposed to incorporate liquid marble microstructures (NaCl/nano-SiO2) encapsulated in organic phases (Octadecane) into the rubber-matrix (SEBS) using the ultrasound-assisted emulsion blending method. The resulting NaCl/SiO2/Octadecane microstructures anchored to SEBS offer a substantial solid-liquid interface consisting of NaCl solution and SiO2. When subjected to an alternating electromagnetic (EM) field, the water molecules and polysorbate within SiO2 exhibit heightened responsiveness to the EM field, and the movement of Na+ and Cl- within these microstructures leads to their accumulation at the solid-liquid interface, creating an asymmetric ion distribution. This phenomenon facilitates enhanced interfacial polarization, thereby contributing to the material's EMW absorption properties. Notably, the latex with 16 wt% SEBS (E-3), exhibiting a surface morphology similar to human cell tissues, achieves complete absorption of X-band (fE = 4.20 GHz, RLmin = -33.87 dB). Moreover, the latex demonstrates light density (0.78 g cm-3) and environmental stability. This study not only highlights the predominant loss mechanism in rubber-based wave-absorbing materials but also provides valuable insights into the design of multifunctional wave-absorbing materials.

2.
Clin Exp Ophthalmol ; 52(2): 148-166, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38214071

RESUMEN

Adult stem cells, present in various parts of the human body, are undifferentiated cells that can proliferate and differentiate to replace dying cells within tissues. Stem cells have specifically been identified in the cornea, trabecular meshwork, crystalline lens, iris, ciliary body, retina, choroid, sclera, conjunctiva, eyelid, lacrimal gland, and orbital fat. The identification of ocular stem cells broadens the potential therapeutic strategies for untreatable eye diseases. Currently, stem cell transplantation for corneal and conjunctival diseases remains the most common stem cell-based therapy in ocular clinical management. Lens epithelial stem cells have been applied in the treatment of paediatric cataracts. Several early-phase clinical trials for corneal and retinal regeneration using ocular stem cells are also underway. Extensive preclinical studies using ocular stem cells have been conducted, showing encouraging outcomes. Ocular stem cells currently demonstrate great promise in potential treatments of eye diseases. In this review, we focus on the identification, characterisation, and therapeutic application of adult stem cells in the eye.


Asunto(s)
Células Madre Adultas , Oftalmopatías , Cristalino , Humanos , Niño , Retina , Cristalino/química , Córnea , Oftalmopatías/terapia , Párpados
3.
Ecotoxicol Environ Saf ; 272: 116084, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38350217

RESUMEN

Polyhexamethylene guanidine (PHMG) is manufactured and applied extensively due to its superior disinfectant capabilities. However, the inhalatory exposure to PHMG aerosols is increasingly recognized as a potential instigator of pulmonary fibrosis, prompting an urgent call for elucidation of the underlying pathophysiological mechanisms. Within this context, alveolar macrophages play a pivotal role in the primary immune defense in the respiratory tract. Dysregulated lipid metabolism within alveolar macrophages leads to the accumulation of foam cells, a process that is intimately linked with the pathogenesis of pulmonary fibrosis. Therefore, this study examines PHMG's effects on alveolar macrophage foaminess and its underlying mechanisms. We conducted a 3-week inhalation exposure followed by a 3-week recovery period in C57BL/6 J mice using a whole-body exposure system equipped with a disinfection aerosol generator (WESDAG). The presence of lipid-laden alveolar macrophages and downregulation of pulmonary tissue lipid transport proteins ABCA1 and ABCG1 were observed in mice. In cell culture models involving lipid-loaded macrophages, we demonstrated that PHMG promotes foam cell formation by inhibiting lipid efflux in mouse alveolar macrophages. Furthermore, PHMG-induced foam cells were found to promote an increase in the release of TGF-ß1, fibronectin deposition, and collagen remodeling. In vivo interventions were subsequently implemented on mice exposed to PHMG aerosols, aiming to restore macrophage lipid efflux function. Remarkably, this intervention demonstrated the potential to retard the progression of pulmonary fibrosis. In conclusion, this study underscores the pivotal role of macrophage foaming in the pathogenesis of PHMG disinfectants-induced pulmonary fibrosis. Moreover, it provides compelling evidence to suggest that the regulation of macrophage efflux function holds promise for mitigating the progression of pulmonary fibrosis, thereby offering novel insights into the mechanisms underlying inhaled PHMG disinfectants-induced pulmonary fibrosis.


Asunto(s)
Desinfectantes , Fibrosis Pulmonar , Ratones , Animales , Fibrosis Pulmonar/metabolismo , Guanidina/toxicidad , Guanidina/metabolismo , Ratones Endogámicos C57BL , Aerosoles y Gotitas Respiratorias , Pulmón , Guanidinas/metabolismo , Macrófagos , Desinfectantes/farmacología , Lípidos
4.
Exp Eye Res ; 231: 109470, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37059216

RESUMEN

Meibomian glands (MGs) are vital for ocular surface health. However, the roles of inflammation in the progression of meibomian gland dysfunction (MGD) are largely unknown. In this study, the roles of the inflammation factor interleukin-1ß (IL-1ß) via the p38 mitogen-activated protein kinases (MAPK) signaling pathway on rat meibomian gland epithelial cells (RMGECs) were explored. Eyelids from adult rat mice at 2 months and 2 years of age were stained with specific antibodies against IL-1ß to identify inflammation levels. RMGECs were exposed to IL-1ß and/or SB203580, a specific inhibitor of p38 MAPK signaling pathway, for 3 days. Cell proliferation, keratinization, lipid accumulation, and matrix metalloproteinases 9 (MMP9) expression were evaluated by MTT assay, polymerase chain reaction (PCR), immunofluorescence staining, apoptosis assay, lipid staining, and Western blot analyses. We found that IL-1ß was significantly higher in the terminal ducts of MGs in rats with age-related MGD than in young rats. IL-1ß inhibited cell proliferation, suppressed lipid accumulation and peroxisome proliferator activator receptor γ (PPARγ) expression, and promoted apoptosis while activating the p38 MAPK signaling pathway. Cytokeratin 1 (CK1), a marker for complete keratinization, and MMP9 in RMGECs were also up-regulated by IL-1ß. SB203580 effectively diminished the effects of IL-1ß on differentiation, keratinization, and MMP9 expression by blocking IL-1ß-induced p38 MAPK activation, although it also inhibited cell proliferation. The inhibition of the p38 MAPK signaling pathway blocked IL-1ß-induced differentiation reduction, hyperkeratinization, and MMP9 overexpression of RMGECs, which provides a potential therapy for MGD.


Asunto(s)
Glándulas Tarsales , Proteínas Quinasas p38 Activadas por Mitógenos , Ratas , Ratones , Animales , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Glándulas Tarsales/metabolismo , Sistema de Señalización de MAP Quinasas/fisiología , Metaloproteinasa 9 de la Matriz/metabolismo , Interleucina-1beta/farmacología , Interleucina-1beta/metabolismo , Células Epiteliales/metabolismo , Inflamación/metabolismo , Lípidos
5.
Support Care Cancer ; 31(12): 685, 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-37945765

RESUMEN

BACKGROUND: Liver cancer is a serious global health problem and is associated with poor spiritual health. Bibliotherapy is beneficial in improving health outcomes in cancer patients, yet there is a lack of empirical evidence of its effect on the spiritual health of liver cancer patients in China. The study aimed to investigate the effects of bibliotherapy based on Chinese traditional culture on the spiritual health of patients with liver cancer in China. This study was approved by the Ethics Committee of Hunan Normal University School of Medicine and registered with the Chinese Clinical Trial Registry with the registration (No: 2021260), which registration in June 30th 2021. METHODS: A total of 60 patients with liver cancer were divided into the intervention group (n = 30) and the control group (n = 30) through WeChat. The intervention group received bibliotherapy therapy based on traditional Chinese culture, while the control group received routine care. Spiritual health was assessed using the Spiritual Attitude and Involvement List (SAIL) and compared before and after the intervention between the two groups. The chi-square test and t-test were used to analyze the intervention effects. RESULTS: The two groups were comparable in all baseline characteristics including the SAIL score. After 5 weeks of intervention, the score of SAIL increased significantly from 96.76 ± 15.08 to 106.93 ± 13.82 in the intervention group (t = - 29.380, p < 0.001), while no significant difference in SAIL score was observed in the control group (from 95.27 ± 16.40 to 95.31 ± 16.24, t = - 0.189, p = 0.852). Similar patterns were also observed in its three dimensions of connecting with oneself, connecting with the environment, and connecting with transcendence. CONCLUSIONS: Our study showed that bibliotherapy based on traditional Chinese culture using the WeChat platform can greatly improve the spiritual health of patients with liver cancer and has the potential to be widely applied to cancer patients to improve their well-being.


Asunto(s)
Biblioterapia , Neoplasias Hepáticas , Humanos , Biblioterapia/métodos , China , Pueblos del Este de Asia/psicología , Lenguaje , Neoplasias Hepáticas/psicología , Neoplasias Hepáticas/terapia , Espiritualidad
6.
Int J Mol Sci ; 23(19)2022 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-36232512

RESUMEN

Sericin is a by-product of the silk industry. Its recycling contributes to environmental protection and the sustainable development of the cocoon silk industry. In this paper, on the basis of realizing sericin enrichment in solution, the Cu(II) adsorption capacities of sericin-derived carbon (SC), prepared at different pyrolysis temperatures, were studied. SC was characterized using scanning electron microscopy (SEM) and the zeta potential. The effects of the initial concentration of Cu(II), pH, adsorption temperature, and contact time on the adsorption process were evaluated, followed by an investigation of the mechanism of Cu(II) adsorption by SC. The results showed that SC has a porous structure that provides sites for Cu(II) adsorption. The maximum adsorption capacity of Cu(II) onto SC1050, 17.97 mg/g, was obtained at an adsorption temperature of 35 °C and a pH of 5.5. In addition, the pseudo-second-order kinetic model and Langmuir isotherm model correctly described the adsorption process of Cu(II) onto SC1050. Therefore, SC can act as a potential adsorbent for removing Cu(II) from water. This study helps promote the effective use of cocoon silk resources.


Asunto(s)
Sericinas , Contaminantes Químicos del Agua , Adsorción , Carbono , Cobre/química , Concentración de Iones de Hidrógeno , Cinética , Sericinas/química , Agua/química , Contaminantes Químicos del Agua/química
7.
Int J Mol Sci ; 23(3)2022 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-35163591

RESUMEN

The recycling and reuse of biomass waste for the preparation of carbon-based adsorbents is a sustainable development strategy that has a positive environmental impact. It is well known that a large amount of silk sericin (SS) is dissolved in the wastewater from the silk industry. Utilizing the SS instead of discharging it into the environment without further treatment would reduce environmental and ecological problems. However, effective enrichment of the SS from the aqueous solution is a challenge. Here, with the help of carboxymethyl chitosan (CMCS), which can form a gel structure under low voltage, an SS/CMCS hydrogel with SS as the major component was prepared via electrodeposition at a 3 V direct-current (DC) voltage for five minutes. Following a carbonization process, an SS-based adsorbent with good performance for the removal of methylene blue (MB) from an aqueous solution was prepared. Our results reveal that the SS/CMCS hydrogel maintains a porous architecture before and after carbonization. Such structure provides abundant adsorption sites facilitating the adsorption of MB molecules, with a maximum adsorptive capacity of 231.79 mg/g. In addition, it suggests that the adsorption is an exothermic process, has a good fit with the Langmuir model, and follows the intra-particle diffusion model. The presented work provides an economical and feasible path for the treatment of wastewater from dyeing and printing.


Asunto(s)
Carbono/química , Galvanoplastia , Azul de Metileno/química , Sericinas/química , Contaminantes Químicos del Agua/química , Purificación del Agua
8.
Org Biomol Chem ; 18(11): 2170-2174, 2020 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-32140694

RESUMEN

A copper-catalyzed C-H [3 + 2] annulation of N-substituted anilines with α-carbonyl alkyl bromides for the synthesis of 3,3'-disubstituted oxindoles is developed. Tandem C-H cycloamidation reactions of various α-carbonyl alkyl bromide derivatives including tertiary-α-bromoalkyl ketone esters, malonic esters and cycloalkanes, with N-aryl or alkyl substituted anilines, can be performed using this system, affording a vast array of valuable 3,3'-disubstituted oxindoles in moderate to good yields.

9.
Org Biomol Chem ; 18(25): 4843-4847, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32608447

RESUMEN

A simple and practical method for the synthesis of phosphoryl-substituted indolo[2,1-a]isoquinolin-6(5H)-ones and benzimidazo[2,1-a]isoquinolin-6(5H)-ones through manganese(iii)-promoted tandem phosphinoylation/cyclization of 2-arylindoles or 2-arylbenzimidazoles with disubstituted phosphine oxides was developed. In this transformation, new C-P bond and C-C bond were constructed simultaneously under silver-free conditions, exhibiting a broad substrate scope. It was noted that not only diarylphosphine oxides but also dialkyl and arylalkyl-phosphine oxides were compatible with the conditions.

10.
Support Care Cancer ; 28(8): 3533-3542, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32090284

RESUMEN

PURPOSE: Sarcopenia is increasingly recognized as an independent risk factor for poor outcomes in patients undergoing hematopoietic stem cell transplantation (HSCT), and it is a potentially modifiable factor. The purpose of the present systematic review and meta-analysis is to summarize and integrate current evidence in this field. METHODS: We searched EMBASE, MEDLINE, and Cochrane DSR through Ovid and PubMed websites to identify relevant studies. Studies evaluated sarcopenia before HSCT and reported associations between sarcopenia and post-transplant outcomes were included. Two authors independently applied eligibility criteria, assessed quality, and extracted data. Odds ratio (OR) and their 95% confidence intervals (CIs) were pooled to examine the association between sarcopenia and post-transplant outcomes by using the review manager 5.3 software. RESULTS: Seven retrospective cohort studies met our inclusion criteria. The overall quality of studies was low to moderate. Sarcopenia was associated with higher non-relapse mortality [odds ratio (OR) 1.97; 95% CI 1.45, 2.68; P < 0.0001; I2 = 0%] and shorter overall survival [odds ratio (OR) 0.44; 95% CI 0.26, 0.75; P = 0.002; I2 = 65%] in patients undergoing HSCT. CONCLUSIONS: Clinicians could use sarcopenia to balance the risks and benefits of transplantation as early as possible; in addition, interventions can be used to prevent sarcopenia and improve physical function and quality of life. Well-designed, prospective, and large-scale clinical studies are needed to consolidate the evidence.


Asunto(s)
Neoplasias Hematológicas/patología , Neoplasias Hematológicas/terapia , Trasplante de Células Madre Hematopoyéticas/métodos , Sarcopenia/patología , Supervivientes de Cáncer , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Pronóstico , Estudios Prospectivos , Calidad de Vida , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
11.
J Am Chem Soc ; 141(6): 2508-2515, 2019 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-30654609

RESUMEN

Polymeric carbon nitride (C3N4) has emerged as the most promising candidate for metal-free photocatalysts but is plagued by low activity due to the poor quantum efficiency and low specific surface area. Exfoliation of bulk crystals into ultrathin nanosheets has proven to be an effective and widely used strategy for enabling high photocatalytic performances; however, this process is complicated, time-consuming, and costly. Here, we report a simple bottom-up method to synthesize porous few-layer C3N4, which involves molecule self-assembly into layered precursors, alcohol molecules intercalation, and subsequent thermal-induced exfoliation and polycondensation. The as-prepared few-layer C3N4 expose more active sites and greatly enhance the separation of charge carriers, thus exhibiting a 26-fold higher hydrogen evolution activity than bulk counterpart. Furthermore, we find that both the high activity and selectivity for the oxidative coupling of amines to imines can be obtained under visible light that surpass those of other metal-free photocatalysts so far.

12.
J Environ Qual ; 47(5): 1179-1185, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30272787

RESUMEN

In this work we investigate the role of soil texture in petroleum vapor intrusion (PVI) by performing numerical modeling, analytical calculations, and statistical analysis of the USEPA's PVI database. Numerical simulations were conducted for three kinds of soil (sand, sandy loam, and clay), and the results indicate that the maximum attenuations of vapor concentrations from source to indoor air were observed when the clay soil is below the building. In the anaerobic zone, the normalized soil gas concentration profiles were observed to be similar and independent of soil type, whereas in the aerobic zone, a more significant attenuation was observed in finer grained soils. Such a finding is consistent with the statistical results of the USEPA's PVI database, which indicate that in the near-source zone, the soil gas concentration in coarse-grained soil tends to be lower than that in fine-grained soil, possibly caused by a weaker source due to mass loss by volatilization, whereas at a distance away from the source, the measured soil gas concentrations in fine-grained soils become much lower because of aerobic biodegradation with a shorter diffusive reaction length. Thus, 3 and 5 m are proposed as soil-type-dependent vertical screening distances for fine and coarse-grained soils, respectively. It should be noted that the validity of these screening distances is examined only for relatively homogeneous soils, and they may not be applicable for cases involving layered soil systems, where the availability of O in the subfoundation should be evaluated with subslab or multidepth samples to confirm the presence of aerobic biodegradation.


Asunto(s)
Modelos Químicos , Petróleo/análisis , Contaminantes del Suelo/química , Suelo/química , Volatilización
13.
Artículo en Inglés | MEDLINE | ID: mdl-38885109

RESUMEN

In recent years, the neural implicit surface has emerged as a powerful representation for multi-view surface reconstruction due to its simplicity and state-of-the-art performance. However, reconstructing smooth and detailed surfaces in indoor scenes from multi-view images presents unique challenges. Indoor scenes typically contain large texture-less regions, making the photometric loss unreliable for optimizing the implicit surface. Previous work utilizes monocular geometry priors to improve the reconstruction in indoor scenes. However, monocular priors often contain substantial errors in thin structure regions due to domain gaps and the inherent inconsistencies when derived independently from different views. This paper presents DebSDF to address these challenges, focusing on the utilization of uncertainty in monocular priors and the bias in SDF-based volume rendering. We propose an uncertainty modeling technique that associates larger uncertainties with larger errors in the monocular priors. High-uncertainty priors are then excluded from optimization to prevent bias. This uncertainty measure also informs an importance-guided ray sampling and adaptive smoothness regularization, enhancing the learning of fine structures. We further introduce a bias-aware signed distance function to density transformation that takes into account the curvature and the angle between the view direction and the SDF normals to reconstruct fine details better. Our approach has been validated through extensive experiments on several challenging datasets, demonstrating improved qualitative and quantitative results in reconstructing thin structures in indoor scenes, thereby outperforming previous work.

14.
Small Methods ; : e2301783, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38195803

RESUMEN

Semiquinone (SQ) radicals play a critical role in the long-lasting UV-blocking application of lignin, while their origin and stable structure are unclear. Here, the organosolv lignin extracted from poplar (OL-P) is self-assembled into normal micelles (LNM) with more phenolic hydroxyl groups on the surface, and reverse micelles (LRM) with more methoxyl groups on the surface. After 12 h UV irradiation, the SQ radical contents in LNM and LRM increase 33% and 78% respectively. The performance of LNM based sunscreen keeps upswinging due to radical stabilization of phenolic hydroxyl groups. LRM based sunscreen experiences a gradual decrease after reaching maximum UV absorbance due to the quick generation and over oxidation of SQ radicals. Density functional theory (DFT) simulations reveal that methoxyl groups in OL-P has bigger bond length and smaller bond dissociation enthalpy than phenolic hydroxyl groups, and are easy to form SQ radicals. The Gibbs free energy (ΔG) needed for SQ-quinone transformation is above 26.10 kcal mol.-1 , while that for SQ-hydroquinone transformation is below -66.78 kcal mol.-1 . Hydroquinone is the stable structure of SQ radicals. This work discloses the origin and stable structure of SQ radicals in lignin under UV irradiation, and provides an important guidance for its long-lasting UV-blocking application.

15.
Thorac Cancer ; 15(7): 559-569, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38294282

RESUMEN

BACKGROUND: Neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are closely related to the prognosis of patients with non-small cell lung cancer, but their effect on extensive-stage small cell lung cancer (ES-SCLC) remains uncertain. METHODS: This retrospective study was conducted in ES-SCLC patients treated with first-line atezolizumab or durvalumab and platinum-etoposide. Clinical data from three hospitals were analyzed. Significant risk factors for survival were identified using descriptive statistics and Cox regression. Homogeneity was assessed using t-tests or nonparametric tests. Kaplan-Meier analysis revealed an association between high NLR level and median PFS and OS. RESULTS: A total of 300 ES-SCLC patients were included in the study. Cox regression analysis revealed that an elevated NLR level after the second treatment cycle (defined as NLRT2) was an independent prognostic factor for survival. Stratifying patients based on median NLRT2 showed significant differences in both PFS (HR: 1.863, 95% CI: 1.62-2.12, p < 0.001) and OS (HR: 2.581, 95% CI: 2.19-3.04, p < 0.001) between NLR ≥ 1.75 and NLR < 1.75 groups. mPFS and mOS were 8.2 versus 6.1 months and 13.7 versus 9.5 months, respectively. NLR was also associated with treatment efficacy and occurrence of irAEs. Further stratification based on NLR and irAEs showed that in the NLR < 1.75 group, patients with irAEs had prolonged mPFS and mOS. In the NLR ≥ 1.75 group, only mPFS showed a significant difference between patients with and without irAEs. CONCLUSION: NLRT2 and irAEs can predict the prognosis of ES-SCLC patients with first-line ES-SCLC receiving PD-L1 inhibitors combined with chemotherapy.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células Pequeñas , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neutrófilos , Pronóstico , Estudios Retrospectivos , Linfocitos
16.
Chem Commun (Camb) ; 60(38): 5026-5029, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38629636

RESUMEN

In the research presented herein, low-valent-tungsten-catalyzed hydroboration of esters and nitriles was investigated. Aromatic and aliphatic substrates were smoothly reduced to corresponding alcohol derivatives and N,N-diborylamines in the presence of W(CO)4(NCMe)2. Valuable derivatives were conveniently accessed by introducing a further functionalization process to crude hydroboration mixtures in one pot.

17.
Environ Sci Pollut Res Int ; 30(14): 42192-42213, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36645605

RESUMEN

Traditional method of estimating pollution loads may neglect the internal spatial heterogeneity of socio-economic driving factors, which can result in overestimate and underestimate of pollution loads. In this study, the corrected approach to estimating total phosphorus (TP) pollution load was proposed to explore its future variation to develop effective phosphorus pollution control strategies for water environment management. As the first-class tributary of the Yangtze River, the TP out of limits in the Tuojiang River is serious. Thus, based on the presently related basic datasets related to TP pollution load estimation, we firstly adopted the GM (1,1) model to predict their varied trends from 2021 to 2025. We then used the pollution emission coefficient method to calculate the TP pollution load. Moreover, considering the temporal and spatial heterogeneity of the pollutant generation coefficient, we further introduced population and GDP factors to further modify the pollutant generation coefficient to correct TP pollution load. Finally, we employed the exploratory spatial data analysis (ESDA) method to explore spatial distribution characteristics and spatial autocorrelation of TP pollution load from diverse pollution sources in 2025. The results showed that the total TP pollution load from diverse pollution sources will increase from 12,194.92 t in 2021 to 12,461.26 t in 2025, an increase of 2.18%. More concretely, the TP pollution load from rural domestic sewage, rural domestic waste and livestock, and poultry pollution sources will separately decrease by 94.24 t, 77.9 t, and 86.52 t. However, the TP pollution load from agricultural runoff and agricultural solid wastes pollution sources will increase by 74.52 t and 451.49 t, respectively. The contribution of TP pollution load from diverse pollution sources to total TP pollution load will be as follows: livestock and poultry (63.49%) > agricultural solid wastes (16.72%) > agricultural runoff (12.26%) > rural domestic sewage (4.12%) > rural domestic waste (3.41%). The difference in the spatial distribution of TP pollution load from diverse pollution sources in 2025 will be prominent. TP pollution from rural domestic sewage and rural domestic waste pollution sources is more serious in the Xindu and Longquanyi districts, and that from agricultural runoff and agricultural solid wastes pollution sources is more prominent in the midstream and downstream. TP pollution load from livestock and poultry pollution source is higher in the Renshou, Anyue, Rongxian, Luxian counties, and Jiangyang district. Additionally, TP pollution load from rural domestic sewage, rural domestic waste, agricultural runoff, and agricultural solid wastes pollution sources in 2025 will show a clear spatial correlation, but the spatial correlation of TP pollution load from livestock and poultry pollution source will be weak. The study is effective to eliminate the influence of temporal and spatial variation of pollutants generates coefficients on TP pollution load estimation. The method can reflect the actual condition of pollution loads in watersheds more objectively, which can be applied to estimate other pollution loads of similar watersheds with intensive socio-economic activities. The findings in this study can provide a critical reference for the stakeholders to balance water environment conservation and socio-economic development.


Asunto(s)
Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Fósforo/análisis , Aguas del Alcantarillado , Residuos Sólidos , Nitrógeno/análisis , China , Agua
18.
Psychol Res Behav Manag ; 16: 619-635, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36911044

RESUMEN

Purpose: Based on the affective event theory and the theoretical framework of "work environment features-work events-emotional responses-work attitude", this study aims to explore how and when home-based telework negatively affects work engagement by focusing on the dual chain mediating paths of "workplace isolation-negative emotion" and "telepressure-negative emotion", and the moderating role of family-supportive leadership. Methods: A questionnaire survey was used to collect 276 self-reported responses from employees with home-based telework experience in China. Findings: (a) Home-based telework indirectly and negatively affects work engagement through the mediating chain of "workplace isolation-negative emotion"; (b) Home-based telework indirectly and negatively affects work engagement through the mediating chain of "telepressure-negative emotion"; (c) Family-supportive leadership negatively moderates the chain mediating effect of "workplace isolation-negative emotion" and "telepressure-negative emotion" between home-based telework and work engagement. In other words, the higher the level of family-supportive leadership, the weaker the negative effect of home-based telework on work engagement. Originality/Value: This study sheds additional light on the relationship between home-based telework and work engagement by constructing the influence mechanism model of home-based telework on work engagement, in which "workplace isolation-negative emotion" and "telepressure-negative emotion" act as chain mediators, and family supportive leadership as moderator. This study enriches the literature on home-based telework. Practical Implications: The findings indicates that home-based work has indirectly and negatively effects on work engagement through dual chain mediating paths of "workplace isolation-negative emotion" and "telepressure-negative emotion". However, family-supportive leadership can weaken this negative influence. Therefore, organizations need to cultivate family supportive leadership.

19.
Viruses ; 15(10)2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37896818

RESUMEN

Deformed wing virus (DWV) is one of the important pathogens of the honey bee (Apis mellifera), which consists of three master variants: types A, B, and C. Among them, DWV types A (DWV-A) and B (DWV-B) are the most prevalent variants in honey bee colonies and have been linked to colony decline. DWV-A and DWV-B have different virulence, but it is difficult to distinguish them via traditional methods. In this study, we established a visual detection assay for DWV-A and DWV-B using recombinase polymerase amplification (RPA) and a lateral flow dipstick (LFD) coupled with the clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein (Cas) 12a fluorescence system (RPA-CRISPR-Cas12a-LFD). The limit of detection of this system was ~6.5 × 100 and 6.2 × 101 copies/µL for DWV-A and DWV-B, respectively. The assays were specific and non-cross-reactive against other bee viruses, and the results could be visualized within 1 h. The assays were validated by extracting cDNA from 36 clinical samples of bees that were suspected to be infected with DWV. The findings were consistent with those of traditional reverse transcription-quantitative polymerase chain reaction, and the RPA-CRISPR-Cas12a assay showed the specific, sensitive, simple, and appropriate detection of DWV-A and DWV-B. This method can facilitate the visual and qualitative detection of DWV-A and DWV-B as well as the monitoring of different subtypes, thereby providing potentially better control and preventing current and future DWV outbreaks.


Asunto(s)
Virus ARN , Recombinasas , Abejas , Animales , Recombinasas/genética , Sistemas CRISPR-Cas , Fluorescencia , Virus ARN/genética
20.
Biotechnol Biofuels Bioprod ; 16(1): 175, 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-37974275

RESUMEN

BACKGROUND: The direct bioconversion of crude glycerol, a byproduct of biodiesel production, into 1,3-propanediol by microbial fermentation constitutes a remarkably promising value-added applications. However, the low activity of glycerol dehydratase, which is the key and rate-limiting enzyme in the 1,3-propanediol synthetic pathway, caused by crude glycerol impurities is one of the main factors affecting the 1,3-propanediol yield. Hence, the exploration of glycerol dehydratase resources suitable for crude glycerol bioconversion is required for the development of 1,3-propanediol-producing engineered strains. RESULTS: In this study, the novel glycerol dehydratase 2eGDHt, which has a tolerance against crude glycerol impurities from Klebsiella pneumoniae 2e, was characterized. The 2eGDHt exhibited the highest activity toward glycerol, with Km and Vm values of 3.42 mM and 58.15 nkat mg-1, respectively. The optimum pH and temperature for 2eGDHt were 7.0 and 37 °C, respectively. 2eGDHt displayed broader pH stability than other reported glycerol dehydratases. Its enzymatic activity was increased by Fe2+ and Tween-20, with 294% and 290% relative activities, respectively. The presence of various concentrations of the crude glycerol impurities, including NaCl, methanol, oleic acid, and linoleic acid, showed limited impact on the 2eGDHt activity. In addition, the enzyme activity was almost unaffected by the presence of an impurity mixture that mimicked the crude glycerol environment. Structural analyses revealed that 2eGDHt possesses more coil structures than reported glycerol dehydratases. Moreover, molecular dynamics simulations and site-directed mutagenesis analyses implied that the existence of unique Val744 from one of the increased coil regions played a key role in the tolerance characteristic by increasing the protein flexibility. CONCLUSIONS: This study provides insight into the mechanism for enzymatic action and the tolerance against crude glycerol impurities, of a novel glycerol dehydratase 2eGDHt, which is a promising glycerol dehydratase candidate for biotechnological conversion of crude glycerol into 1,3-PDO.

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