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1.
Small ; : e2310289, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38597769

RESUMO

The high exciton binding energy (Eb) and sluggish surface reaction kinetics have severely limited the photocatalytic hydrogen production activity of carbon nitride (CN). Herein, a hybrid system consisting of nitrogen defects and Pt single atoms is constructed through a facile self-assembly and photodeposition strategy. Due to the acceleration of exciton dissociation and regulation of local electron density of Pt single atoms along with the introduction of nitrogen defects, the optimized Pt-MCT-3 exhibits a hydrogen production rate of 172.0 µmol h-1 (λ ≥ 420 nm), ≈41 times higher than pristine CN. The apparent quantum yield for the hydrogen production is determined to be 27.1% at 420 nm. The experimental characterizations and theoretical calculations demonstrate that the nitrogen defects act as the electron traps for the exciton dissociation, resulting in a decrease of Eb from 86.92 to 43.20 meV. Simultaneously, the stronger interaction between neighboring nitrogen defects and Pt single atoms directionally drives free electrons to aggregate around Pt single atoms, and tailors the d-band electrons of Pt, forming a moderate binding strength between Pt atoms and H* intermediates.

2.
Molecules ; 29(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38611763

RESUMO

Salvia miltiorrhiza seeds (SMS) are the main by-product of the production processing of Radix Salviae Miltiorrhizae. The main purposes of this work are to analyse the nutritional components in SMS, to explore the antioxidant activity of the chemical components in SMS and to evaluate the possibility of SMS as a raw material for functional foods. The contents of crude fibre, total protein, carbohydrates, total phenolics and flavonoids in SMS and the composition and relative content of fatty acids in SMS oil were determined. The results suggested that SMS has high contents of crude fibre (28.68 ± 4.66 g/100 g), total protein (26.65 ± 2.51 g/100 g), total phenolics (6.45 ± 0.55 mg of gallic acid equivalent/g) and total flavonoids (3.28 ± 0.34 mg of rutin equivalent/g), as well as a high level of α-linolenic acid (33.774 ± 4.68%) in their oil. Twenty-two secondary metabolites were identified in SMS residue, and nine compounds were isolated. The IC50 values of the total phenolic content in SMS on an ABTS radical, DPPH radical, superoxide radical and hydroxyl radical were 30.94 ± 3.68 µg/mL, 34.93 ± 4.12 µg/mL, 150.87 ± 17.64 µg/mL and 230.19 ± 24.47 µg/mL, respectively. The results indicate that SMS contain many nutrients and have high utilization value as a promising functional food.


Assuntos
Antioxidantes , Magnésio , Radioisótopos , Salvia miltiorrhiza , Antioxidantes/farmacologia , Flavonoides , Fenóis , Compostos Fitoquímicos/farmacologia , Sementes
3.
Food Chem ; 448: 139125, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38537547

RESUMO

In this study, the ultrasonic-microwave pretreatment was defined as a processing technology in the production of tribute citrus powder, and it could increase the flavonoid compounds in the processing fruit powder. A total of 183 upregulated metabolites and 280 downregulated metabolites were obtained by non-targeted metabolomics, and the differential metabolites was mainly involved in the pathways of flavonoid biosynthesis, flavone and flavonol biosynthesis. A total of 8 flavonoid differential metabolites were obtained including 5 upregulated metabolites (6"-O-acetylglycitin, scutellarin, isosakuranin, rutin, and robinin), and 3 downregulated metabolites (astragalin, luteolin, and (-)-catechin gallate) by flavonoids-targeted metabolomics. The 8 flavonoid differential metabolites participated in the flavonoid biosynthesis pathways, flavone and flavonol biosynthesis pathways, and isoflavonoid biosynthesis pathways. The results provide a reference for further understanding the relationship between food processing and food components, and also lay a basis for the development of food targeted-processing technologies.


Assuntos
Citrus , Flavonoides , Frutas , Metabolômica , Citrus/metabolismo , Citrus/química , Flavonoides/metabolismo , Flavonoides/química , Frutas/química , Frutas/metabolismo , Pós/química , Pós/metabolismo , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Manipulação de Alimentos
4.
Front Immunol ; 15: 1339213, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38348038

RESUMO

Background: Radiofrequency ablation (RFA) is the primary curative treatment for hepatocellular carcinoma (HCC) patients who are not eligible for surgery. However, the effects of RFA on the global tumor immune response remain unclear. Method: In this study, we examined the phenotypic and functional changes in peripheral blood mononuclear cells (PBMCs) from recurrent HCC patients who had undergone two RFA treatments using mass cytometry and high-throughput mRNA assays. Results: We observed significant increase in monocytes and decrease in T cell subpopulations three days after the first RFA treatment and three days after the second RFA treatment. The down-regulation of GZMB, GZMH, GZMK, and CD8A, which are involved in the cytotoxic function of T cells, was observed following RFA. Furthermore, the population of CD8 effector and memory T cells (CD8 Teff and CD8 Tem) significantly decreased after RFA. The expression of CD5 and CD161 in various T cell subpopulations also showed significant reductions. Additionally, elevated secretion of VEGF was observed in monocytes, B cells, regulatory T cells (Tregs), and CD4 naive T cells. Conclusion: In recurrent HCC patients, serum components derived from radiofrequency therapy can enhance the antigen-presenting capacity of monocytes. However, they also inhibit the anti-cancer immune response by reducing the population of CD8 effector and memory T cells and suppressing the activation of T cells, as well as down-regulating the expression of CD161 and CD5 in various T cell subpopulations. These tumor-derived components also contribute to an immunosuppressive microenvironment by promoting the secretion of VEGF in monocytes, Tregs, B cells, and CD4 naive T cells.


Assuntos
Carcinoma Hepatocelular , Ablação por Cateter , Neoplasias Hepáticas , Ablação por Radiofrequência , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Leucócitos Mononucleares , Fator A de Crescimento do Endotélio Vascular , Terapia de Imunossupressão , Microambiente Tumoral
5.
Compr Rev Food Sci Food Saf ; 23(1): e13290, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38284591

RESUMO

Aquatic foods are nutritious, enjoyable, and highly favored by consumers. In recent years, young consumers have shown a preference for prefabricated food due to its convenience, nutritional value, safety, and increasing market share. However, aquatic foods are prone to microbial spoilage due to their high moisture content, protein content, and unsaturated fatty acids. Furthermore, traditional processing methods of aquatic foods can lead to issues such as protein denaturation, lipid peroxidation, and other food safety and nutritional health problems. Therefore, there is a growing interest in exploring new technologies that can achieve a balance between antimicrobial efficiency and food quality. This review examines the mechanisms of cold plasma, high-pressure processing, photodynamic inactivation, pulsed electric field treatment, and ultraviolet irradiation. It also summarizes the research progress in nonthermal physical field technologies and their application combined with other technologies in prefabricated aquatic food. Additionally, the review discusses the current trends and developments in the field of prefabricated aquatic foods. The aim of this paper is to provide a theoretical basis for the development of new technologies and their implementation in the industrial production of prefabricated aquatic food.


Assuntos
Manipulação de Alimentos , Conservação de Alimentos , Qualidade dos Alimentos , Valor Nutritivo , Inocuidade dos Alimentos
6.
Bioengineered ; 15(1): 2305029, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38258524

RESUMO

Oats (Avena sativa L.) are one of the worldwide cereal crops. Avenanthramides (AVNs), the unique plant alkaloids of secondary metabolites found in oats, are nutritionally important for humans and animals. Numerous bioactivities of AVNs have been investigated and demonstrated in vivo and in vitro. Despite all these, researchers from all over the world are taking efforts to learn more knowledge about AVNs. In this work, we highlighted the recent updated findings that have increased our understanding of AVNs bioactivity, distribution, and especially the AVNs biosynthesis. Since the limits content of AVNs in oats strictly hinders the demand, understanding the mechanisms underlying AVN biosynthesis is important not only for developing a renewable, sustainable, and environmentally friendly source in both plants and microorganisms but also for designing effective strategies for enhancing their production via induction and metabolic engineering. Future directions for improving AVN production in native producers and heterologous systems for food and feed use are also discussed. This summary will provide a broad view of these specific natural products from oats.


• Avenanthramides are unique nutritional alkaloids in oats• AVN bioactivity, distribution, and the potential AVNs biosynthesis are discussed• AVNs can be produced via induction and metabolic engineering.


Assuntos
Avena , Grão Comestível , Animais , Humanos , ortoaminobenzoatos , Amidas , Fenóis
7.
J Environ Manage ; 351: 119764, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38100867

RESUMO

Indoor air, especially with suspended particulate matter (PM), can be a carrier of airborne infectious pathogens. Without sufficient ventilation, airborne infectious diseases can be transmitted from one person to another. Indoor air quality (IAQ) significantly impacts people's daily lives as people spend 90% of their time indoors. An industrial-grade air cleaner prototype (filtration + ultraviolet light) was previously upgraded to clean indoor air to improve IAQ on two metrics: particulate matter (PM) and viable airborne bacteria. Previous experiments were conducted to test its removal efficiency on PM and airborne bacteria between the inlet and treated air. However, the longer-term improvement on IAQ would be more informative. Therefore, this research focused on quantifying longer-term improvement in a testing environment (poultry facility) loaded with high and variable PM and airborne bacteria concentrations. A 25-day experiment was conducted to treat indoor air using an air cleaner prototype with intermittent ON and OFF days in which PM and viable airborne bacteria were measured to quantify the treatment effect. The results showed an average of 55% reduction of total suspended particulate (TSP) concentration between OFF days (110 µg/m3) and ON days (49 µg/m3). An average of 47% reduction of total airborne viable bacteria concentrations was achieved between OFF days (∼3200 CFU/m3) and ON days (∼2000 CFU/m3). A cross-validation (CV) model was established to predict PM concentrations with five input variables, including the status of the air cleaner, time (h), ambient temperature, indoor relative humidity, and day of the week to help simulate the air-cleaning effect of this prototype. The model can approximately predict the air quality trend, and future improvements may be made to improve its accuracy.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Humanos , Material Particulado/análise , Poluição do Ar em Ambientes Fechados/prevenção & controle , Poluição do Ar em Ambientes Fechados/análise , Raios Ultravioleta , Melhoria de Qualidade , Bactérias , Monitoramento Ambiental , Poluentes Atmosféricos/análise , Tamanho da Partícula
8.
Shock ; 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38010286

RESUMO

ABSTRACT: The adenosine concentration and forkhead box protein (Foxp3) expression in T regulatory cells (Tregs) are increased during sepsis. However, the mechanism by which adenosine induces Foxp3 expression is incompletely understood. A cecal ligation and puncture (CLP) model was constructed using C57BL/J mice. The plasma adenosine concentration and Foxp3 expression in splenic Tregs were increased consistently for 15 days after sepsis onset. Analysis of the mean fluorescence intensity of Foxp3 and adenosine concentration in the same mice revealed a linear correlation. In the CLP model, adenosine 2a receptor (A2aR) blockade inhibited Foxp3 expression in Tregs. In vitro activation of A2aR promoted Foxp3 expression in Tregs and facilitated secretion of extracellular vesicles. Transcriptome sequencing revealed that A2aR blockade led to changes in cyclic adenosine monophosphate response element-binding protein (CREB) transcription in Tregs in our sepsis model. Use of adenosine or A2aR agonists promoted CREB expression, CREB phosphorylation at S133, Treg expression of Foxp3, and enhanced inhibition of proliferation of cluster of differentiation (CD)4+ lymphocytes. A2aR blockade or inhibition of CREB expression inhibited Foxp3 expression in Tregs. In the CLP model, use of CREB inhibitors could inhibit Foxp3 expression and reduce the bacterial load. In summary, adenosine in sepsis promotes CREB phosphorylation via A2aR which, in turn, upregulates Foxp3 expression in Tregs.

9.
Light Sci Appl ; 12(1): 248, 2023 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-37805511

RESUMO

Achievement of high photoluminescence quantum efficiency and thermal stability is challenging for near-infrared (NIR)-emitting phosphors. Here, we designed a "kill two birds with one stone" strategy to simultaneously improve quantum efficiency and thermal stability of the NIR-emitting Ca3Y2-2x(ZnZr)xGe3O12:Cr garnet system by chemical unit cosubstitution, and revealed universal structure-property relationship and the luminescence optimization mechanism. The cosubstitution of [Zn2+-Zr4+] for [Y3+-Y3+] played a critical role as reductant to promote the valence transformation from Cr4+ to Cr3+, resulting from the reconstruction of octahedral sites for Cr3+. The introduction of [Zn2+-Zr4+] unit also contributed to a rigid crystal structure. These two aspects together realized the high internal quantum efficiency of 96% and excellent thermal stability of 89%@423 K. Moreover, information encryption with "burning after reading" was achieved based on different chemical resistance of the phosphors to acid. The developed NIR-emitting phosphor-converted light-emitting diode demonstrated promising applications in bio-tissue imaging and night vision. This work provides a new perspective for developing high-performance NIR-emitting phosphor materials.

10.
Accid Anal Prev ; 193: 107282, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37722256

RESUMO

For crash severity modeling, researchers typically view theory-driven models and data-driven models as different or even conflicting approaches. The reason is that the machine-learning models offer good predictability but weak interpretability, while the latter has robust interpretability but moderate predictability. In order to alleviate the tension between them, this study proposes an integrated data- and theory-driven crash-severity model, known as Embedded Fusion model based on Text Vector Representations (TVR-EF), by leveraging the complementary strengths of both. The model specification consists of two parts. (i) the data-driven component not only mitigate the deficiencies of traditional econometric models, where one-hot encoding is frequently used and makes it impossible to observe semantic relatedness between variable categories, but also enhances the interpretability for the relationship between crash severity and potential influencing factors using the learned embedding weight matrix. (ii) In the theory-driven component, the multinomial logit model is implemented as a 2D-Convolutional Neural Network (2D-CNN) to increase flexibility and decrease dependency on prior knowledge for different crash-severity outcomes. A crash dataset from Guangdong Province, China, is utilized to estimate the TVR-EF model, which is then benchmarked against two traditional econometric models and three widely used machine-learning models. Results indicate that TVR-EF model does not only improve the predictive performance but also makes it easier to interpret.

11.
Angew Chem Int Ed Engl ; 62(45): e202311699, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37724623

RESUMO

Lead-free halide double perovskites are currently gaining significant attention owing to their exceptional environmental friendliness, structural adjustability as well as self-trapped exciton emission. However, stable and efficient double perovskite with multimode luminescence and tunable spectra are still urgently needed for multifunctional photoelectric application. Herein, holmium based cryolite materials (Cs2 NaHoCl6 ) with anti-thermal quenching and multimode photoluminescence were successfully synthesized. By the further alloying of Sb3+ (s-p transitions) and Yb3+ (f-f transitions) ions, its luminescence properties can be well modulated, originating from tailoring band gap structure and enriching electron transition channels. Upon Sb3+ substitution in Cs2 NaHoCl6 , additional absorption peaking at 334 nm results in the tremendous increase of photoluminescence quantum yield (PLQY). Meanwhile, not only the typical NIR emission around 980 nm of Ho3+ is enhanced, but also the red and NIR emissions show a diverse range of anti-thermal quenching photoluminescence behaviors. Furthermore, through designing Yb3+ doping, the up-conversion photoluminescence can be triggered by changing excitation laser power density (yellow-to-orange) and Yb3+ doping concentration (red-to-green). Through a combined experimental-theoretical approach, the related luminescence mechanism is revealed. In general, by alloying Sb3+ /Yb3+ in Cs2 NaHoCl6 , abundant energy level ladders are constructed and more luminescence modes are derived, demonstrating great potential in multifunctional photoelectric applications.

12.
Vet Sci ; 10(7)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37505823

RESUMO

This study aimed to assess the morphometry of enterocytes as well as the goblet cell-to-enterocyte ratio in different intestinal segments of dogs with chronic enteropathies (CE). Histopathological intestinal samples from 97 dogs were included in the study (19 healthy juveniles, 21 healthy adults, 24 dogs with protein-losing enteropathy (PLE), and 33 CE dogs without PLE). Healthy adult small intestinal enterocytes showed progressively reduced epithelial cell height in the aboral direction, while juvenile dogs showed progressively increased epithelial cell height in the aboral direction. CE dogs had increased epithelial cell height in the duodenum, while PLE dogs had decreased epithelial cell heights compared to healthy adult dogs. Both the CE and PLE dogs showed decreased enterocyte width in the duodenal segment, and the ileal and colonic enterocytes of CE dogs were narrower than those of healthy adult dogs. CE dogs had a lower goblet cell-to-enterocyte ratio in the colon segment compared to healthy dogs. This study provides valuable morphometric information on enterocytes during canine chronic enteropathies, highlighting significant morphological enterocyte alterations, particularly in the small intestine, as well as a reduced goblet cell-to-enterocyte ratio in the colon of CE cases compared to healthy adult dogs.

13.
Food Chem ; 413: 135574, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36739644

RESUMO

Cell adhesion of four cultivars of tomato fruit, "Micro Tom (MT)", "Heinz 1706 (H1706)", "Money Maker (MM)", "Ailsa Craig (AC)" were evaluated and cell walls were analyzed in order to assess the possible contribution of pectic and hemicellulosic polysaccharides to the softening and altered cell adhesion at two different stages of ripeness. Cell wall material (CWM) and solubilised fractions of green and red ripe fruit were analyzed by chemical, enzymatic techniques. In comparison with the four cultivars of tomato fruits, H1706 and MM are harder than MT and AC at both green and red ripe stage. The ripening-associated solubilisation of rhamnogalacturonan-riched pectic polysaccharides was reduced in H1706 and MM, and the content of side -chain sugars from RG-I reduced by more than 50% in MT and AC. In addition to recognized pectic modifying enzymes, RGase had a good effect on cell separation of H1706 and MM fruit at red ripe stage. The higher RG-I content and branching degree have been associated with increased cell adhesion and reduced cell wall porosity, thus maintained fruit firmness.


Assuntos
Pectinas , Solanum lycopersicum , Pectinas/metabolismo , Frutas/metabolismo , Adesão Celular , Polissacarídeos/análise , Parede Celular/química
14.
ACS Appl Mater Interfaces ; 15(2): 3152-3162, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36604858

RESUMO

Increasing the crystal resistivity is critically important for enhancing the signal-to-noise ratio and improving the sensing capability of high-temperature piezoelectric sensors based on langasite-type crystals. The resistivity of structural ordered langasite-type crystals is much higher compared to that of the disordered crystals. Here, we selected structural ordered Ca3TaGa3Si2O14 (CTGS) and disordered La3Ga5SiO14 (LGS) as representatives to investigate the microscopic conduction mechanism and further reveal the origin of the different resistivities of the ordered and disordered langasite-type crystals at elevated temperatures. By combining first-principles calculations and experimental investigations, we found that the different conductivity behaviors of the ordered and disordered crystals originate from different types of point defects formed in the crystal and their different contributions to the conductivity. For the disordered LGS crystal, the oxygen vacancies are apt to be formed at high temperatures, promoting the transition of valence electrons and yielding high conductivity. For the ordered CTGS crystal, the dominant TaGa antisite defects can introduce an electron-hole recombination center in the electronic band gap, significantly shortening the carrier lifetime and thus reducing the conductivity. This provides effective guidance to improve the resistivity performance of langasite-type crystals at high temperatures by optimizing the experimental conditions, such as oxygen atmosphere treatment, antisite defect modification, etc.

15.
Crit Rev Food Sci Nutr ; 63(31): 10959-10973, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35648042

RESUMO

Recent studies have explored the field of extracellular vesicles (EVs), driving an increasing interest in their application to human health. EVs have unique physicochemical traits to participate in intercellular communication, thus fostering the idea of using EVs to yield synergistic, preventive, and therapeutic effects. Many reports have shown that EVs contain natural bioactive compounds, such as lipids, proteins, RNA, and other active components that regulate biological processes, thereby contributing to human health. Therefore, in this review, we comprehensively elucidate various facets of the relationship between EVs and bioactive compounds that modulate EVs contents, including RNAs and proteins, discussing different forms of biological regulation. The use of EVs for cargo-loading bioactive compounds to exert biological functions and methods to load bioactive compounds into EVs are also discussed. This review highlighted the effect of EV-delivered bioactive compounds on several therapeutic mechanisms and applications, providing new insight into nutrition and pharmacology.


Assuntos
Vesículas Extracelulares , Humanos , Vesículas Extracelulares/metabolismo , Comunicação Celular , Proteínas/metabolismo
16.
World J Gastrointest Oncol ; 14(12): 2393-2403, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36568948

RESUMO

BACKGROUND: Increasing evidence have shown that regional lymph node metastasis is a critical prognostic factor in gastric cancer (GC). In addition, lymph node dissection is a key factor in determining the appropriate treatment for GC. However, the association between the number of positive lymph nodes and area of lymph node metastasis in GC remains unclear. AIM: To investigate the clinical value of regional lymph node sorting after radical gastrectomy for GC. METHODS: This study included 661 patients with GC who underwent radical gastrectomy at Tianjin Medical University General Hospital between January 2012 and June 2020. The patients were divided into regional sorting and non-sorting groups. Clinicopathological data were collected and retrospectively reviewed to determine the differences in the total number of lymph nodes and number of positive lymph nodes between the groups. Independent sample t-tests were used for intergroup comparisons. Continuous variables that did not conform to a normal distribution were expressed as median (interquartile range), and the Mann-Whitney U test was used for inter-group comparisons. RESULTS: There were no significant differences between the groups in terms of the surgical method, tumor site, immersion depth, and degree of differentiation. The total number of lymph nodes was significantly higher in the regional sorting group (n = 324) than in the non-sorting group (n = 337) (32.5 vs 21.2, P < 0.001). There was no significant difference in the number of positive lymph nodes between the two groups. A total of 212 patients with GC had lymph node metastasis in the lymph node regional sorting group, including 89 (41.98%) cases in the first dissection station and 123 (58.02 %) cases in the second dissection station. Binary and multivariate logistic regression results showed that the number of positive lymph nodes (P < 0.001) was an independent risk factor for lymph node metastases at the second dissection station. CONCLUSION: Regional sorting of lymph nodes after radical gastrectomy may increase the number of detected lymph nodes, thereby improving the reliability and accuracy of lymph node staging in clinical practice.

17.
Artigo em Inglês | MEDLINE | ID: mdl-36498208

RESUMO

Since the COVID-19 pandemic, improving indoor air quality (IAQ) has become vital for the public as COVID-19 and other infectious diseases can transmit via inhalable aerosols. Air cleaning devices with filtration and targeted pollutant treatment capabilities can help improve IAQ. However, only a few filtration/UV devices have been formally tested for their effectiveness, and little data is publicly available and UV doses comparable. In this research, we upgraded a particulate matter (PM) air filtration prototype by adding UV-C (germicidal) light. We developed realistic UV dose metrics for fast-moving air and selected performance scenarios to quantify the mitigation effect on viable airborne bacteria and PM. The targeted PM included total suspended particulate (TSP) and a coarse-to-fine range sized at PM10, PM4, PM2.5, and PM1. The PM and viable airborne bacteria concentrations were compared between the inlet and outlet of the prototype at 0.5 and 1.0 m3/s (low and high) air flow modes. The upgraded prototype inactivated nearly 100% of viable airborne bacteria and removed up to 97% of TSP, 91% of PM10, 87% of PM4, 87% of PM2.5, and 88% of PM1. The performance in the low flow rate mode was generally better than in the high flow rate mode. The combination of filtration and UV-C treatment provided 'double-barrier' assurance for air purification and lowered the risk of spreading infectious micro-organisms.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , COVID-19 , Humanos , Material Particulado/análise , Pandemias , Tamanho da Partícula , COVID-19/prevenção & controle , Aerossóis e Gotículas Respiratórios , Poluição do Ar em Ambientes Fechados/prevenção & controle , Poluição do Ar em Ambientes Fechados/análise , Bactérias , Poluentes Atmosféricos/análise , Monitoramento Ambiental
18.
Biotechnol Biofuels Bioprod ; 15(1): 123, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36380342

RESUMO

BACKGROUND: Polyunsaturated fatty acid (PUFA) synthase is a multi-domain mega-enzyme that effectively synthesizes a series of PUFAs in marine microorganisms. The dehydratase (DH) domain of a PUFA synthase plays a crucial role in double bond positioning in fatty acids. Sequencing results of the coccolithophore Emiliania huxleyi (E. huxleyi, Eh) indicated that this species contains a PUFA synthase with multiple DH domains. Therefore, the current study, sought to define the functions of these DH domains (EhDHs), by cloning and overexpressing the genes encoding FabA-like EhDHs in Escherichia coli (E. coli) and Arabidopsis thaliana (A. thaliana). RESULTS: A complementation test showed that the two FabA-like DH domains could restore DH function in a temperature-sensitive (Ts) mutant. Meanwhile, overexpression of FabA-like EhDH1 and EhDH2 domains increased the production of unsaturated fatty acids (UFAs) in recombinant E. coli by 43.5-32.9%, respectively. Site-directed mutagenesis analysis confirmed the authenticity of active-site residues in these domains. Moreover, the expression of tandem EhDH1-DH2 in A. thaliana altered the fatty acids content, seed weight, and germination rate. CONCLUSIONS: The two FabA-like DH domains in the E. huxleyi PUFA synthase function as 3-hydroxyacyl-acyl carrier protein dehydratase in E. coli. The expression of these domains in E. coli and A. thaliana can alter the fatty acid profile in E. coli and increase the seed lipid content and germination rate in A. thaliana. Hence, introduction of DH domains controlling the dehydration process of fatty acid biosynthesis in plants might offer a new strategy to increase oil production in oilseed plants.

19.
Artigo em Inglês | MEDLINE | ID: mdl-36078535

RESUMO

To a certain degree, the resilience of the transportation system expresses the safety of the transportation system, because it reflects the ability of the system to maintain its function in the face of disturbance events. In the current research, the assessment of the resilience of urban mobility is attractive and challenging. Apart from this, the concept of green mobility has been popular in recent years. As a representative way of shared mobility, the implementation of ridesharing will affect the level of urban mobility resilience to a certain extent. In this paper, we use a data low-intensity method to evaluate the urban traffic resilience under the circumstance of restricted car use. In addition, we incorporate the impact of ridesharing services. The research in this paper can be regarded as an evaluation framework, which can help policy makers and relevant operators to grasp the overall resilience characteristics of cities in emergencies, identify weak sectors, and formulate the best response plan. This method has been successfully applied to two cities in China, demonstrating its potential for practice. Finally, we also explored the relationship between urban traffic resilience and the pattern of population distribution. The analysis shows that population density has an impact on the level of transportation resilience. And the incorporation of ridesharing will bring an obvious increment in resilience of most areas.


Assuntos
Meios de Transporte , China , Cidades , Densidade Demográfica
20.
Light Sci Appl ; 11(1): 112, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35478191

RESUMO

Near-infrared (NIR)-emitting phosphor-converted light-emitting diodes have attracted widespread attention in various applications based on NIR spectroscopy. Except for typical Cr3+-activated NIR-emitting phosphors, next-generation Cr3+-free NIR-emitting phosphors with high efficiency and tunable optical properties are highly desired to enrich the types of NIR luminescent materials for different application fields. Here, we report the Fe3+-activated Sr2-yCay(InSb)1-zSn2zO6 phosphors that exhibit unprecedented long-wavelength NIR emission. The overall emission tuning from 885 to 1005 nm with broadened full-width at half maximum from 108 to 146 nm was realized through a crystallographic site engineering strategy. The NIR emission was significantly enhanced after complete Ca2+ incorporation owing to the substitution-induced lower symmetry of the Fe3+ sites. The Ca2InSbO6:Fe3+ phosphor peaking at 935 nm showed an ultra-high internal quantum efficiency of 87%. The as-synthesized emission-tunable phosphors demonstrated great potential for NIR spectroscopy detection. This work initiates the development of efficient Fe3+-activated broadband NIR-emitting phosphors and opens up a new avenue for designing NIR-emitting phosphor materials.

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