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1.
Medicine (Baltimore) ; 103(18): e37794, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38701297

RESUMEN

BACKGROUND: This study aims to evaluate the effect of telephone and short-message follow-ups on compliance and efficacy in asthmatic children treated with inhaled corticosteroids. METHODS: A total of 120 children with moderate bronchial asthma who visited the Asthma Outpatient Department of the Affiliated Hospital of Qingdao University were enrolled in the study. They were divided randomly into 3 groups based on the type of follow-up given: a combined telephone and short-message service (Tel + SMS) group, a SMS group, and a control group. After being followed up for 12 weeks, each child's asthma control level was assessed and their lung function was measured. RESULTS: The compliance rates of children in the Tel + SMS group and SMS group were 86.49% and 56.25%, respectively. The total effective rates of these 2 groups (94.59% and 75.0%, respectively) were significantly higher than the rate of the control group (P < .01). The lung function indicators of the children in all 3 groups were better than those before treatment, although only the Tel + SMS group and SMS group improved significantly (P < .05). The lung function indicators of the large and small airways in the Tel + SMS group and the SMS group were also significantly better than those of the control group (P < .01). The results of the study suggest that 1 of the causes of poor compliance in asthmatic children is fear of an adverse reaction to inhaled corticosteroids. CONCLUSION: Telephone and short-message follow-ups can increase compliance with inhaled corticosteroid treatment and improve the asthma control levels and lung function of asthmatic children.


Asunto(s)
Corticoesteroides , Asma , Teléfono , Humanos , Asma/tratamiento farmacológico , Niño , Masculino , Femenino , Administración por Inhalación , Corticoesteroides/administración & dosificación , Corticoesteroides/uso terapéutico , Envío de Mensajes de Texto , Cumplimiento de la Medicación/estadística & datos numéricos , Resultado del Tratamiento , Pruebas de Función Respiratoria , Antiasmáticos/administración & dosificación , Antiasmáticos/uso terapéutico , Antiasmáticos/efectos adversos , Adolescente , Preescolar
2.
Biochem Genet ; 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724713

RESUMEN

As a member of Rho GAPs family, Rho GTPase-Activating Protein 17 (ARHGAP17) regulates cytoskeletal recombination, cell polarity, cell proliferation and cell migration. ARHGAP17 is identified as a tumor suppressor in numerous cancer types. Current study intends to examine ARHGAP17 expression and its possible influence on the progression of hepatocellular carcinoma (HCC). ARHGAP17 expression in HCC cells was verified by RT-PCR and western blot. The proliferation and invasion of HCC cells were evaluated by CCK8 assay and transwell assay, respectively. The mRNA expression of ARHGAP17, PCNA, E-cadherin, N-cadherin, ß-catenin, GSK-3ß, Axin1, and APC were detected by RT-PCR. The protein expression of ARHGAP17, PCNA, E-cadherin, N-cadherin, ß-catenin, p-ß-catenin, GSK-3ß, p-GSK-3ß, Axin1, and APC were detected by western blot. ARHGAP17 staining was evaluated by immunohistochemistry and immunofluorescence. ARHGAP17 expression decreased significantly in HCC tumors and HCC cells after EMT. In response to overexpression of ARHGAP17, the capacities of HCC cell proliferation and invasion were reduced significantly, which were also confirmed by tumorigenesis experiments in vivo. With overexpression of ARHGAP17 in HCC cells, the p-GSK3ß/GSK3ß decreased, while the p-ß-catenin/ß-catenin, Axin1 and APC increased. In conclusion, ARHGAP17 inhibits HCC progression by inactivating the Wnt/ß-catenin signaling pathway.

3.
Cancer Biol Ther ; 25(1): 2334463, 2024 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-38569536

RESUMEN

Neurensin-2 (NRSN2) performs a pro-carcinogenic function in multiple cancers. However, the function of NRSN2 in HPV-infected laryngeal carcinoma (LC) remains unclear. HPV transfection was performed in LC cells. The mRNA and protein levels were monitored using RT-qPCR, immunoblotting, and IF. Cell viability and proliferation were found using the CCK-8 assay and Edu staining. Cell invasion, migration, and apoptosis were probed using the Transwell, wound healing, and flow cytometry, respectively. The autophagosome was observed using TEM. NRSN2 was overexpressed in HPV-transfected LC cells. Inhibition of NRSN2 restrained the autophagy and malignant behavior of HPV-transfected LC cells. Meanwhile, the inhibition of AMPK/ULK1 pathway limited the increased autophagy of HPV-transfected LC cells caused by NRSN2 overexpression. Furthermore, NRSN2 knockdown inhibits autophagy by suppressing AMPK/ULK1 pathway, thereby restraining the malignant behavior of HPV-transfected LC cells. Our research confirmed that HPV transfection increased the autophagy and malignant behavior of LC cells by regulating the NRSN2-mediated activation of the AMPK/ULK1 pathway, offering a new target for cure of LC.


Asunto(s)
Carcinoma , Infecciones por Papillomavirus , Humanos , Proteínas Quinasas Activadas por AMP , Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Autofagia/genética , Péptidos y Proteínas de Señalización Intracelular
4.
Environ Pollut ; 348: 123879, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38548161

RESUMEN

Desorption is a critical process in the recovery or post-treatment of adsorbents saturated with volatile organic compounds (VOCs). In this study, the thermal desorption behaviors for eight VOCs on hypercrosslinked polymeric resin (HPR) and macroporous polymeric resin (MPR) were investigated through isothermal desorption and temperature programmed desorption (TPD). Compared with MPR, HPR with more micropores exhibited a lower desorption rate constant, lower desorption efficiency and higher desorption activation energy due to the strong binding energy generated between VOCs molecules and narrow micropores. As the polarizability of VOCs increased, the desorption rate constants on two porous polymeric resins decreased, while the desorption activation energy showed an incremental trend. Excellent linear correlations were observed between VOC polarizability and desorption rate constants (R2 = 0.957 for HPR and R2 = 0.940 for MPR) as well as between VOC polarizability and desorption activation energy (R2 = 0.981 for HPR and R2 = 0.969 for MPR). Furthermore, a polyparameter linear free energy relationship (PP-LFER) was developed to explore the influences of intermolecular interactions on desorption behaviors of VOCs on porous polymeric resins. The results indicated that the dispersive interaction, which is directly related to polarizability of VOCs, was the primary factor influencing the desorption activation energy of VOCs on porous polymeric resins. The find from this study helps evaluate fleetly and availably the desorption properties of VOCs based on their polarizability.


Asunto(s)
Compuestos Orgánicos Volátiles , Compuestos Orgánicos Volátiles/química , Porosidad , Polímeros/química , Temperatura , Adsorción
5.
Sci Total Environ ; 924: 171521, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38458445

RESUMEN

The catalytic activity of TiO2 is contingent upon its crystal structure and the optoelectronic properties associated with defects. In this study, a one-step method was used to synthesize TiO2 with a spatial interface of rutile/anatase phases, and a simple thermal annealing process was applied to optimize the amorphous regions and oxygen vacancies at the interface between the rutile and anatase phases of TiO2. High-resolution transmission electron microscopy (HRTEM) elucidates the evolution process of the amorphous domain at the interface, skillfully introducing oxygen vacancies at the heterojunction interface by modulating the amorphous domain. The obtained photocatalyst (TiO2-350 °C) after annealing exhibits an optimal interface structure, with its photocatalytic activity and stability in degrading toluene far superior to P25. Photocurrent and photoluminescence (PL) measurements affirm that the existence of interfacial oxygen vacancies heightens the efficiency of electron transfer at the interface, while surface oxygen vacancies significantly enhance the stability and mineralization rate of toluene degradation. The improved photocatalytic properties were attributed to the combined effects of surface/interface oxygen vacancies and spatial interface heterojunctions. The one-step synthesis method developed in this work provides a novel perspective on combining spatially interfaced anatase/rutile phases with surface/interfacial oxygen vacancies.

6.
RSC Adv ; 14(7): 4482-4491, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38312729

RESUMEN

Acid rain can lower the pH of groundwater and affect its hydrogeochemistry and microbial ecology. However, the effects of acid rain on the hydrogeochemistry and microbial ecology of red soil groundwater systems in southern China are poorly understood. Previous research had mainly investigated the sources and patterns of groundwater acidification, but not the microbial mechanisms that contribute to this process and their associations with hydrochemical factors. To address this knowledge gap, we conducted a soil column experiment to simulate the infiltration of acid rain through various filter materials (coarse, medium, and fine sand) and to examine the hydrochemical and microbial features of the infiltrate, which can reveal how simulated acid rain (pH 3.5-7.0) alters the hydrochemistry and microbial community composition in red soil aquifers. The results showed that the pH of the leachate decreased due to simulated acid rain, and that the leaching efficiency of nitrogen and metal ions was influenced by the particle size of the filter media. Illumina 16S rRNA gene sequencing revealed that the leachate was dominated by Proteobacteria, Patescibacteria, Actinobacteria, and Acidobacteria, with Proteobacteria accounting for 67.04-74.69% of the bacterial community and containing a high proportion of nitrifying and denitrifying bacteria. Additionally, several genera with heavy metal tolerance, such as Burkholderia-Caballeronia-Paraburkholderia, Delftia, Methylversatilis, Aquicella, and Ralstonia, were widely distributed in the leachate, indicating the strong adaptive capacity of the microbial population. A correlation analysis between the hydrochemical factors and the microbial community structure revealed that pH was the most influential factor, followed by NO2--N, Fe, Al, Cu, Mn, and others. These results indicate that acidification modifies the hydrochemical conditions of the aquifer, creating an environment that is unfavorable for microbial growth and survival. However, some microorganisms may acquire resistance genes to cope with environmental changes.

7.
Environ Pollut ; 346: 123603, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38373622

RESUMEN

Microplastics, ubiquitous anthropogenic marine pollutants, represent potential threats to coral-Symbiodiniaceae relationships in global reef ecosystems. However, the mechanism underlying the impacts of polystyrene microplastics (PS-MPs) on Symbiodiniaceae remains poorly understood. In this study, the cytological, physiological, and microbial responses of Symbiodinium tridacnidorum, a representative Symbiodiniaceae species, to varying concentrations of PS-MPs (0, 5, 50, 100, and 200 mg L-1) were investigated. The results revealed that microplastic exposure inhibited cell division, resulting in reduced cell density compared to control group. Furthermore, algal photosynthetic activity, as indicated by chlorophyll content, Fv/Fm, and net photosynthetic rate, declined with increasing microplastic concentration up to 50 mg L-1. Notably, elevated levels of microplastics (100 and 200 mg L-1) prompted a significant increase in cell size in S. tridacnidorum. Transmission electron microscopy and fluorescence microscopy indicated that hetero-aggregation was formed between high levels of PS-MPs and algal cells, ultimately causing damage to S. tridacnidorum. Moreover, the impact of PS-MPs exposure on the bacterial community associated with S. tridacnidorum was investigated. The results showed a reduction in alpha diversity of the bacterial community in groups exposed to 50, 100, and 200 mg L-1 of microplastics compared to those treated with 0 and 5 mg L-1. Additionally, the relative abundance of Marinobacter, Marivita, and Filomicrobium significantly increased, while Algiphilus and norank Nannocystaceae declined after microplastic exposure. These findings suggest that MPs can inhibit the growth of S. tridacnidorum and alter the associated bacterial community, posing a potential serious threat to coral symbiosis involving S. tridacnidorum.


Asunto(s)
Antozoos , Dinoflagelados , Contaminantes Químicos del Agua , Animales , Microplásticos , Plásticos , Ecosistema , Simbiosis , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis , Fotosíntesis , Poliestirenos , Dinoflagelados/fisiología , Bacterias
8.
Mar Environ Res ; 194: 106339, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38182500

RESUMEN

Increased atmospheric CO2 concentrations not only change the components of inorganic carbon system in seawater, resulting in ocean acidification, but also lead to decreased seawater pH, resulting in ocean acidification. Consequently, increased inorganic carbon concentrations in seawater provide a sufficient carbon source for macroalgal photosynthesis and growth. Increased domestic sewage and industrial wastewater discharge into coastal areas has led to nutrient accumulation in coastal seawaters. Combined with elevated pCO2 (1200 ppmv), increased nutrient availability always stimulates the growth of non-calcifying macroalgae, such as red economical macroalga Gracilariopsis lemaneiformis. Here, we evaluated the interactive effects of nutrients with elevated pCO2 on the economically important marine macroalga Kappaphycus alvarezii (Rhodophyta) in a factorial 21-day coupling experiment. The effects of increased nutrient availability on photosynthesis and photosynthetic pigments of K. alvarezii were greater than those of pCO2 concentration. The highest Fv/Fm values (0.660 ± 0.019 and 0.666 ± 0.030, respectively) were obtained at 2 µmol L-1 of NO3-N at two pCO2 levels. Under the elevated pCO2 condition, the Chl-a content was lowest (0.007 ± 0.004 mg g-1) at 2 µmol L-1 of NO3-N and highest (0.024 ± 0.002 mg g-1) at 50 µmol L-1 of NO3-N. The phycocyanin content was highest (0.052 ± 0.012 mg g-1) at 150 µmol L-1 of NO3-N under elevated pCO2 condition. The malondialdehyde content declined from 32.025 ± 4.558 nmol g-1 to 26.660 ± 3.124 nmol g-1 with the increased nutrients at under low pCO2. To modulate suitable adjustments, soluble biochemical components such as soluble carbohydrate, soluble protein, free amino acids, and proline were abundantly secreted and were likely to protect the integrity of cellular structures under elevated nutrient availability. Our findings can serve as a reference for cultivation and bioremediation methods under future environmental conditions.


Asunto(s)
Algas Comestibles , Rhodophyta , Algas Marinas , Agua de Mar/química , Concentración de Iones de Hidrógeno , Acidificación de los Océanos , Dióxido de Carbono/metabolismo , Rhodophyta/fisiología , Fotosíntesis/fisiología , Carbono/metabolismo , Nutrientes
9.
J Plast Reconstr Aesthet Surg ; 89: 154-163, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38199217

RESUMEN

BACKGROUND: Online resources are commonly used by patients to obtain information on breast reconstruction. Despite the key role of these resources in patient decision-making, their visual content has not yet been evaluated. This study sought to 1) characterize the presence and content of visual aids in online patient education breast reconstruction resources and 2) determine if the women represented in these visual aids reflect the breast reconstruction patient population in the United States. METHODS: The top 10 Google websites and the first 400 Google Images containing photographs/graphics depicting human skin for the search phrase "breast reconstruction" were analyzed. Images were categorized by content as "Before/After," "Surgical/Anatomical," "Step-by-Step," or "Breast-Centric Stock Images." Image subjects were classified by skin tone into "White" or "Non-White" using the Fitzpatrick scale and by body type into "Lean" or "Full-Figured." RESULTS: In total, 471 images were analyzed. These were predominantly "Before/After" images (43.9%), followed by "Breast-Centric Stock Images" (27.4%), "Surgical/Anatomical" (24.2%), and "Step-by-Step" (4.5%). The majority of all images depicted "White" skin types (90.7%) and "Lean" body types (73.0%). "Before/After" images were more likely to show "Full-Figured" women than the other content categories (p < 0.0001) and had the highest percentage of "Non-White" skin types (35.3%). CONCLUSIONS: Our findings demonstrate that breast reconstruction online resources are not reflective of the patient population seeking reconstruction. Improving the diversity of online image resources can both better represent our diverse patient population as well as better align patient expectations with postoperative outcomes, likely improving patient satisfaction.


Asunto(s)
Neoplasias de la Mama , Mamoplastia , Humanos , Femenino , Estados Unidos , Toma de Decisiones , Piel , Mama , Satisfacción del Paciente , Neoplasias de la Mama/cirugía
10.
BMJ Open ; 13(12): e079115, 2023 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-38149414

RESUMEN

OBJECTIVE: Although the herpes zoster vaccine has been available in mainland China since June 2020, residents' knowledge of herpes zoster and the herpes zoster vaccine is poor, and vaccination rates are low, especially among the elderly, who are at high risk for herpes zoster. This study assessed willingness to be vaccinated against herpes zoster and factors associated with vaccination among urban residents in China. METHODS: A mixed-methods study was conducted in community health centres from August 2022 to September 2022. We used convenience sampling to select 2864 residents from 9 Chinese cities for the quantitative study and 67 adults for the qualitative study. A structured questionnaire was used for the quantitative study, and data were collected through face-to-face interviews. Multinomial logistic regression was used to analyse factors associated with willingness to vaccinate. Qualitative data were analysed using thematic analysis of barriers to herpes zoster vaccination. RESULTS: A total of 2864 eligible respondents were included in the study. Of these, 42.67% intended to receive the herpes zoster vaccine, 21.44% refused and 35.89% were hesitant. The results of the quantitative and qualitative analyses showed that the factors associated with respondents' willingness to be vaccinated against herpes zoster included: personal characteristics such as gender, age and income; knowledge and attitudes about herpes zoster and the vaccine; vaccine characteristics such as efficacy, safety and price; and other factors such as pain tolerance and accessibility to vaccination. CONCLUSION: The low willingness to vaccinate, especially among the elderly, is mainly related to their poor knowledge and negative attitude towards the infection and vaccination. Therefore, health education about herpes zoster, immunisation promotion, and improvement of accessibility and affordability would be valuable in China.


Asunto(s)
Vacuna contra el Herpes Zóster , Herpes Zóster , Vacunas , Adulto , Humanos , Anciano , Población Urbana , Herpes Zóster/epidemiología , Herpes Zóster/prevención & control , Herpesvirus Humano 3 , Vacunación , Conocimientos, Actitudes y Práctica en Salud
11.
Biotechnol Biofuels Bioprod ; 16(1): 151, 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37798770

RESUMEN

With the invasion of green tides and the increase of urban green areas worldwide, multimillion tons of Enteromorpha need to be reutilized. In this study, Enteromorpha prolifera powder is considered a promising biomass resource for the production of commercial chemical products production. Ilamycins, novel cyclic heptapeptides with significant anti-TB activities, are isolated from Streptomyces atratus SCSIO ZH16, a deep-sea-derived strain. Using EP powder as a nitrogen source, the production of ilamycins reached 709.97 mg/L through optimization of the nitrogen source using the engineered strain S. atratus SCSIO ZH16 ΔR. After mutant strain constructions and tests, strain S. atratus SCSIO ZH16 ΔR::bldD EP powder achieved a higher production titer of ilamycins. Furthermore, the production titer of ilamycins and ilamycin E reached 1561.77 mg/L and 745.44 mg/L, respectively, in a 5 L bioreactor. This study suggests that E. prolifera is a promising and eco-friendly nitrogen source for the production of ilamycins.

12.
Sci Rep ; 13(1): 16053, 2023 09 25.
Artículo en Inglés | MEDLINE | ID: mdl-37749183

RESUMEN

A xylanase gene (named xyngmqa) was identified from the metagenomic data of the Gumingquan hot spring (92.5 °C, pH 9.2) in Tengchong City, Yunnan Province, southwest China. It showed the highest amino acid sequence identity (82.70%) to endo-1,4-beta-xylanase from Thermotoga caldifontis. A constitutive expression plasmid (denominated pSHY211) and double-layer plate (DLP) method were constructed for cloning, expression, and identification of the XynGMQA gene. The XynGMQA gene was synthesized and successfully expressed in Escherichia coli DH5α. XynGMQA exhibited optimal activity at 90 °C and pH 4.6, being thermostable by maintaining 100% of its activity after 2 h incubated at 80 °C. Interestingly, its enzyme activity was enhanced by high temperatures (70 and 80 °C) and low pH (3.0-6.0). About 150% enzyme activity was detected after incubation at 70 °C for 20 to 60 min or 80 °C for 10 to 40 min, and more than 140% enzyme activity after incubation at pH 3.0 to 6.0 for 12 h. Hydrolytic products of beechwood xylan with XynGMQA were xylooligosaccharides, including xylobiose (X2), xylotriose (X3), and xylotetraose (X4). These properties suggest that XynGMQA as an extremely thermophilic xylanase, may be exploited for biofuel and prebiotic production from lignocellulosic biomass.


Asunto(s)
Manantiales de Aguas Termales , China , Metagenoma , Secuencia de Aminoácidos , Biocombustibles , Escherichia coli/genética
13.
Environ Res ; 238(Pt 1): 117176, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37729962

RESUMEN

Although nonthermal plasma (NTP) technology has high removal efficiency for volatile organic compounds (VOCs), it has limited carbon dioxide (CO2) selectivity, which hinders its practical application. In this study, α-MnO2 nanorods with tunable oxygen vacancies and hydroxyl groups were synthesized by two-step hydrothermal process to enhance their activity for deep oxidation of toluene. Hydrochloric acid (HCl) was used to assist in synthesis of α-MnO2 nanorods with tunable oxygen vacancies, furtherly, more hydroxyl groups were introduced to HCl-assisted synthesized α-MnO2 by K+ supplement. The results showed that the as-synthesized nanorods exhibited superior activity, improved by nearly 30% removal efficiency of toluene compared to pristine MnO2 at SIE = 339 J/L, and reaching high COx selectivity of 72% at SIE = 483 J/L, successfully promoting the deep oxidation of toluene. It was affirmed that oxygen vacancies played an important role in toluene conversion, improving the conversion of ozone (O3) and resulting in higher mobility of surface lattice oxygen species. Besides, the enhancement of deep oxidation performance was caused by the increase of hydroxyl groups concentration. In-situ DRIFTS experiments revealed that the adsorbed toluene on catalyst surface was oxidized to benzyl alcohol by surface lattice oxygen, and hydroxyl groups were also found participating in toluene adsorption. Overall, this study provides a new approach to designing catalysts for deep oxidation of VOCs.


Asunto(s)
Nanotubos , Compuestos Orgánicos Volátiles , Oxígeno , Óxidos , Compuestos de Manganeso , Tolueno , Catálisis
14.
BMC Complement Med Ther ; 23(1): 224, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37420212

RESUMEN

BACKGROUND: Biliary colic (BC) is a frequent hepatobiliary disorder encountered in emergency departments. Acupuncture may be effective as an alternative and complementary medicine for BC. Nonetheless, rigorous trials investigating its efficacy are lacking. Therefore, the aim of this study protocol is to determine whether acupuncture provides immediate relief of pain and associated symptoms in BC patients. METHOD: Eighty-six participants who aged from 18 to 60 years with BC will be recruited in the First People's Hospital of Longquanyi District, Chengdu (West China Longquan Hospital Sichuan University). All participants will be allocated into two treatment groups including acupuncture group and sham acupuncture group using a 1:1 ratio. Each group will only receive a single 30-min needle treatment while waiting for their test results after completing the routine examination for BC. The primary outcome of the study is to assess the change in pain intensity after the 30-min acupuncture treatment. The secondary outcomes of the study include the change in pain intensity at various time points, the degree of gastrointestinal symptoms at different time points, the level of anxiety experienced during pain episodes at different time points, the score of Pain Anxiety Symptoms Scale-20 (PASS-20), the score of Fear of Pain Questionnaire-III (FPQ-III), and the score of Pain Catastrophizing Scale (PCS), among others. DISCUSSION: The results of this research will provide substantial evidence regarding the efficacy of acupuncture in alleviating symptoms associated with BC. TRIAL REGISTRATION: ClinicalTrials.gov, ChiCTR2300070661. Registered on 19 April 2023.


Asunto(s)
Terapia por Acupuntura , Analgesia , Cólico , Humanos , Terapia por Acupuntura/métodos , Dolor , Ansiedad/terapia , Ensayos Clínicos Controlados Aleatorios como Asunto
15.
Environ Pollut ; 330: 121704, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37116569

RESUMEN

Ozone pollution has become one of the most concerned environmental issue. Developing low-cost and efficient catalysts is a promising alternative for ozone decomposition. This work presents a creative strategy that using α-Fe2O3-supported Co3O4 nanoparticles for constructing interfacial oxygen vacancies (Vo) to remove ozone. The efficiency of Co3O4/α-Fe2O3 was superior to that of pure α-Fe2O3 by nearly two times for 200-ppm ozone removal after 6-h reaction at 25 °C, which is ascribed to the highly active interfacial Vo. X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy suggest that the Fe3+-Vo-Co2+ was formed when Co3O4 was loaded in α-Fe2O3. Furthermore, the density functional theory (DFT) calculations reveal the desorption and electron transfer ability of intermediate peroxide (O22-) on Fe3+-Vo-Co2+ are higher than the Vo from other regions. In situ diffuse reflectance Fourier transform (DRIFT) spectroscopy also demonstrate the higher conversion rate of O22- on Co3O4/α-Fe2O3. Base on the intermediates detected, we propose a recycle mechanism of interfacial Vo for ozone removal: O22- is quickly converted to O2- and transformed into O2 on interfacial Vo. Moreover, O2-temperature-programmed desorption (TPD), H2-temperature-programmed reduction (TPR), and electrochemical impedance spectroscopy (EIS) reveal that the oxygen mobility, reducibility, and conductivity of Co3O4/α-Fe2O3 are greatly superior to those of α-Fe2O3, which is contributed to the conversion of O22-. Consequently, our proposed strategy effectively enhances the activity and stability of the bimetallic transition oxides for ozone decomposition.


Asunto(s)
Nanopartículas , Ozono , Ozono/química , Especies Reactivas de Oxígeno , Oxígeno/química
16.
J Phys Condens Matter ; 35(20)2023 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-36881909

RESUMEN

The control of propagation direction or path of edge states is difficult when the chirality of the excitation source and the boundary structures are determined. Here, we studied a frequency-selective routing for elastic wave based on two types of topological phononic crystals (PnCs) with different symmetries. By constructing multiple types of interfaces between different PnCs structures with distinct valley topological phases, the valley edge states of elastic wave could be realized at different frequencies in the band gap. Meanwhile, based on the simulation of topological transport, it is found that the routing path of elastic waves valley edge states highly depends on the operating frequency and the inputting port of the excitation source. By varying the excitation frequency, the transport path can be switched. The results provide a paradigm for the control of elastic wave propagation paths that could be employed for designing the frequency-dependent ultrasonic division devices.

18.
Int J Food Microbiol ; 394: 110177, 2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-36940519

RESUMEN

Penicillium digitatum is one of the most critical phytopathogens during the citrus postharvest period. However, the molecular mechanism of pathogenesis remains to be further explored. Purine is a multiple functional substance in organisms. To verify the role of the de novo purine biosynthesis (DNPB) pathway in P. digitatum, we investigated the third gene Pdgart, glycinamide ribonucleotide (GAR)-transferase, of this pathway in this study. The deletion mutant ΔPdgart was generated in the principle of homologous recombination via Agrobacterium tumefaciens-mediated transformation (ATMT). The phenotypic assay indicated that the ΔPdgart mutant displayed severe defects in hyphae growth, conidiation and germination, which can be rescued by the addition of exogenous ATP and AMP. Compared with wild-type strain N1, the ATP level of strain ΔPdgart was detected to be sharply declined during conidial germination, and this was resulted from the damage to purine synthesis and aerobic respiration. The pathogenicity assay suggested that mutant ΔPdgart infected citrus fruit but attenuated disease, which was owing to its reduced production of organic acids and activities of cell wall degradation enzymes. Additionally, the ΔPdgart mutant showed altered sensitivity to stress agents and fungicides. Taken together, the present study provides insights into the essential functions of Pdgart, and paves the way for further study and novel fungicide development.


Asunto(s)
Citrus , Fungicidas Industriales , Penicillium , Virulencia/genética , Proteínas Fúngicas/genética , Transferasas/metabolismo , Citrus/microbiología , Penicillium/metabolismo , Fungicidas Industriales/farmacología , Mitocondrias/metabolismo , Purinas/metabolismo , Adenosina Trifosfato/metabolismo , Enfermedades de las Plantas/microbiología
19.
J Org Chem ; 88(7): 4145-4154, 2023 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-36952394

RESUMEN

An unprecedented electrochemical cross-dehydrogenative coupling reaction between isochroman and unactivated ketones to directly synthesize α-substituted isochromans has been developed. This strategy provides a facile and efficient procedure to the direct activation of C(sp3)-H bond adjacent to the O atom of isochroman. The method features high atom economy, chemical oxidant-free, and mild conditions, in which methanesulfonic acid (MsOH) acts as both electrolyte and catalyst, making the process more convenient and environmentally friendly. Gram-scale experiment and synthesis of antitumor active compounds demonstrate the great potential of this protocol for practical applications.

20.
Chemosphere ; 313: 137521, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36513199

RESUMEN

Catalytic ozonation is an environmentally friendly technology for the removal of gaseous NH3 due to high NH3 conversion and high N2 selectivity at ambient temperature. However, the influence mechanism of ubiquitous water vapor on catalytic ozonation of NH3 is unclear. In this study, cryptomelane-type manganese oxide (OMS-2) catalyst was prepared and tested for catalytic ozonation of NH3 in different relative humidity. The results showed that water vapor significantly decreased the catalytic activity, which was due to the inhibition of water on NH3 adsorption on Lewis acid sites and O3 decomposition on oxygen vacancies, as well as the combination of water with active oxygen species (O22- and Oatom). And the effect of water vapor on NH3 conversion was more significant than O3 decomposition because more Mn-OH were involved in the O3 decomposition under humid conditions. Combining in-situ DRIFTS results with the performance of NH3 oxidation, it is found that L-2 acid sites (the peak of NH3 adsorption on Lewis acid sites at 1188 cm-1) were the main active sites for adsorption and activation of NH3 in the early stage of catalytic reaction; as the reaction progressed, L-2 acid sites were gradually occupied by water and more Brønsted acid sites participated in the catalytic reaction. This work deepened the understanding of the reaction process for selective catalytic ozonation of NH3, and provided theoretical guidance for the design of efficient hydrophobic catalysts to eliminate gaseous NH3 pollution.


Asunto(s)
Amoníaco , Ozono , Amoníaco/química , Nitrógeno , Vapor , Ácidos de Lewis , Oxígeno , Ozono/química , Catálisis
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