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1.
Phys Chem Chem Phys ; 26(22): 15987-15998, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38775056

RESUMO

The environmental suitability of hydrogen storage materials is significantly influenced by the way aluminum reacts synchronously with water, ice, and water steam. The straightforward ball milling process was used to synthesize Al-based composite materials with carbon nanotubes (CNTs) or graphene oxide (GO). The reactivity of the composites in various types of water was investigated. The Al/Bi/CNT and Al/Bi/GO composites may react in liquid water, low-temperature ice, and high-temperature steam. The hydrolysis promotion of Al-based composites by CNTs is superior to that of GO, whether in liquid water at 20 °C or ice at -20 °C. The maximum hydrogen generation rate of Al/Bi/CNT composites can reach 34.6 mL g-1 s-1 at 20 °C. The hydrogen generation volume of Al/Bi/CNT can reach 700 mL g-1 in 15 min on ice at -20 °C. Moreover, the ignition temperature and ignition delay time of Al/Bi/CNT are shorter than those of Al/Bi/GO in high-temperature steam. The hydrogen generation volume from Al/Bi/CNT at 200 °C can reach 853 mL g-1. These may originate from the unique one-dimensional nanostructure of CNTs, which provides more surface area or reaction sites during the hydrolysis of the composite.

2.
Molecules ; 29(2)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38257334

RESUMO

Trollius chinensis Bunge, a perennial herb belonging to the Ranunculaceae family, has been extensively used in traditional Chinese medicine. Documented in the Supplements to the Compendium of Materia Medica, its medicinal properties encompass a spectrum of applications, including heat clearance, detoxification, alleviation of oral/throat sores, earaches, eye pain, cold-induced fever, and vision improvement. Furthermore, T. chinensis is used in clinical settings to treat upper respiratory infections, pharyngitis, tonsillitis, esoenteritis, canker, bronchitis, etc. It is mainly used to treat inflammation, such as inflammation of the upper respiratory tract and nasal mucosa. This comprehensive review explores the evolving scientific understanding of T. chinensis, covering facets of botany, materia medica, ethnopharmacological use, phytochemistry, pharmacology, and quality control. In particular, the chemical constituents and pharmacological research are reviewed. Polyphenols, mainly flavonoids and phenolic acids, are highly abundant among T. chinensis and are responsible for antiviral, antimicrobial, and antioxidant activities. The flower additionally harbors trace amounts of volatile oil, polysaccharides, and other bioactive compounds. The active ingredients of the flower have fewer side effects, and it is used in children because of its minimal side effects, which has great research potential. These findings validate the traditional uses of T. chinensis and lay the groundwork for further scientific exploration. The sources utilized in this study encompass Web of Science, Pubmed, CNKI site, classic monographs, Chinese Pharmacopoeia, Chinese Medicine Dictionary, and doctoral and master's theses.


Assuntos
Botânica , Materia Medica , Criança , Humanos , Etnofarmacologia , Controle de Qualidade , Inflamação
3.
Anal Chem ; 95(38): 14184-14191, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37721016

RESUMO

Rapid extraction and analysis of target molecules from irregular surfaces are in high demand in the field of on-site analysis. Herein, a flexible platform used for surface-enhanced Raman scattering (SERS) based on an ordered polymer pyramid structure with half-imbedded silver nanoparticles (AgNPs) was prepared to address this issue. The fabrication includes the following steps: (1) creating inverted pyramid arrays in silicon substrate, (2) preparing a layer of AgNPs on the surface of the inverted pyramids, and (3) obtaining a substrate with an ordered polymer pyramids array with half-imbedded AgNPs by the molding method. This flexible substrate is capable of rapid extraction via a simple and convenient "paste and peel off" method. In addition, the substrate exhibits great repeatability and good sensitivity thanks to the uniformity and larger surface area of the ordered pyramids. The density of "hot spots" (local electromagnetic field with high intensity) is increased on the structured surface. Semi-imbedding silver particles in the polymer pyramids makes "hot spots" robust on the substrate. In addition, the preprepared silicon template with the inverted pyramids can be reused, which greatly reduces the production cost. With this substrate, we successfully analyzed thiram molecules on the epidermis of apples, cucumbers, and oranges, and the detection limits are 2.4, 3, and 3 ng/cm2, respectively. These results demonstrate the great potential of the substrate for in situ analysis, which can provide reference for the design of ideal SERS substrates.

4.
Clin Exp Immunol ; 210(3): 309-320, 2022 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-36370151

RESUMO

Non-small cell lung cancer (NSCLC) is the primary reason of tumor morbidity and mortality worldwide. We aimed to study the transfer process of S100A4 between cells and whether it affected NSCLC development by affecting STAT3 expression. First, S100A4 expression in NSCLC cells was measured. The exosomes in MRC-5, A549, and H1299 cells were isolated and identified. We constructed si-S100A4 and si-PD-L1 to transfect A549 cells and oe-S100A4 to transfect H1299 cells, and tested the transfection efficiency. Cell function experiments were performed to assess cell proliferation, clone number, apoptosis, cell cycle, migration, and invasion abilities. In addition, ChIP was applied to determine the targeting relationship between S100A4 and STAT3. Next, we explored NSCLC cell-derived exosomes role in NSCLC progress by transmitting S100A4. Finally, we verified the function of exosome-transmitted S100A4 in NSCLC in vivo. High expression of S100A4 was secreted by exosomes. After knocking down S100A4, cell proliferation ability was decreased, clones number was decreased, apoptosis was increased, G1 phase was increased, S phase was repressed, and migration and invasion abilities were also decreased. ChIP validated STAT3 and PD-L1 interaction. After knocking down S100A4, PD-L1 expression was decreased, while ov-STAT3 reversed the effect of S100A4 on PD-L1 expression. Meanwhile, S100A4 inhibited T-cell immune activity by activating STAT3. In addition, knockdown of PD-L1 inhibited cell proliferation, migration, and invasion. NSCLC cell-derived exosomes promoted cancer progression by transmitting S100A4 to activate STAT3 pathway. Finally, in vivo experiments further verified that exosome-transmitted S100A4 promoted NSCLC progression. Exosome-transmitted S100A4 induces immunosuppression and the development of NSCLC by activating STAT3.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Exossomos , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Antígeno B7-H1/metabolismo , Exossomos/metabolismo , Terapia de Imunossupressão , Proliferação de Células , Linhagem Celular Tumoral , Movimento Celular , Fator de Transcrição STAT3/metabolismo , Proteína A4 de Ligação a Cálcio da Família S100/metabolismo , Proteína A4 de Ligação a Cálcio da Família S100/farmacologia
5.
Phys Chem Chem Phys ; 24(39): 24173-24180, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36168826

RESUMO

The surface morphology of the silicon nanostructure plays a crucial role in the laser desorption/ionization (LDI) process. Understanding the correlation between the surface morphology and LDI performance is the foundation for creating silicon substrates with high LDI efficiency. Most of the present studies focus only on the structural parameters (such as porosity, depth, total surface area, dimension, etc.) of a single structure, but their effects on LDI efficiency vary with the types of silicon structures. Herein, two representative types of silicon nanostructures, porous silicon (PSi) and thorny silicon (TSi), were created to address this issue. The results indicate that the PSi substrate can generate a stronger heat effect and is beneficial to desorption; the TSi substrate can facilitate electron transfer and is favorable to ionization. Subsequently, the assertion was further confirmed by simultaneously detecting a dozen of standard samples and a real sample on both the TSi and PSi substrates, in which PSi can significantly enhance the detection signals of organic salts, whereas the TSi substrate can greatly increase the LDI efficiencies of neutral analytes. This finding provides a foundation for improving the LDI performance by tailoring silicon nanostructures, which is helpful for designing and creating substrates with high LDI performance.

6.
Biotechnol Bioeng ; 118(11): 4347-4359, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34302701

RESUMO

Microbial cell factories provide a sustainable and economical way to produce chemicals from renewable feedstocks. However, the accumulation of targeted chemicals can reduce the robustness of the industrial strains and affect the production performance. Here, the physiological functions of Mediator tail subunit CgMed16 at l-malate stress were investigated. Deletion of CgMed16 decreased the survival, biomass, and half-maximal inhibitory concentration (IC50 ) by 40.4%, 34.0%, and 30.6%, respectively, at 25 g/L l-malate stress. Transcriptome analysis showed that this growth defect was attributable to changes in the expression of genes involved in lipid metabolism. In addition, tolerance transcription factors CgUSV1 and CgYAP3 were found to interact with CgMed16 to regulate sterol biosynthesis and glycerophospholipid metabolism, respectively, ultimately endowing strains with excellent membrane integrity to resist l-malate stress. Furthermore, a dynamic tolerance system (DTS) was constructed based on CgUSV1, CgYAP3, and an l-malate-driven promoter Pcgr-10 to improve the robustness and productive capacity of Candida glabrata. As a result, the biomass, survival, and membrane integrity of C. glabrata 012 (with DTS) increased by 22.6%, 31.3%, and 53.8%, respectively, compared with those of strain 011 (without DTS). Therefore, at shake-flask scale, strain 012 accumulated 35.5 g/L l-malate, and the titer and productivity of l-malate increased by 32.5% and 32.1%, respectively, compared with those of strain 011. This study provides a novel strategy for the rational design and construction of DTS for dynamically enhancing the robustness of industrial strains.


Assuntos
Candida glabrata , Membrana Celular , Proteínas Fúngicas , Malatos/metabolismo , Engenharia Metabólica , Estresse Fisiológico , Candida glabrata/genética , Candida glabrata/crescimento & desenvolvimento , Membrana Celular/genética , Membrana Celular/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
7.
Appl Microbiol Biotechnol ; 105(12): 5173-5187, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34115183

RESUMO

Microbial cell factories offer an economic and environmentally friendly method for the biosynthesis of acetyl-CoA-derived chemicals. However, the static control of carbon flux can cause direct and indirect competition for acetyl-CoA between cell growth and chemical biosynthesis, limiting the efficiency of microbial cell factories. Herein, recombinase-based genetic circuits were developed to achieve the optimal distribution of acetyl-CoA between cell growth and butyrate biosynthesis. First, three dynamic devices-a turn-on switch, a turn-off switch, and a recombinase-based inverter (RBI)-were constructed based on Bxb1 recombinase. Then, the turn-on switch was used to dynamically control the butyrate biosynthetic pathway, which directly improved the consumption of acetyl-CoA. Next, the turn-off switch was applied to dynamically control cell growth, which indirectly enhanced the supply of acetyl-CoA. Finally, an RBI was adopted for the dynamic dual control of the distribution of acetyl-CoA between cell growth and butyrate biosynthesis. The final butyrate production rate was increased to 34 g/L, with a productivity of 0.405 g/L/h. The strategy described herein will pave the way for the development of high-performance microbial cell factories for the production of other desirable chemicals. KEY POINTS: • Competition for acetyl-CoA between cell growth and synthesis limits productivity. • Recombinase-based genetic circuits were developed to dynamic control of acetyl-CoA. • Optimal distribution of acetyl-CoA between cell growth and synthesis was achieved.


Assuntos
Escherichia coli , Engenharia Metabólica , Acetilcoenzima A , Butiratos , Ciclo do Carbono , Escherichia coli/genética
8.
J Environ Manage ; 230: 1-13, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30261440

RESUMO

To meet the needs of a fast growing global population, agriculture and livestock production have been intensified, resulting in environmental pollution, climate change, and soil health declining. Closing the nutrient circular loop is one of the most important sustainability factors that affect these issues. Apart from being a serious environmental issue, the discharge of N and P via agricultural wastewater is also a major factor that disturbs nutrient cycling in agriculture. In this study, the performance, in terms of recovery, of N and P (individually, as well as simultaneously) from agricultural wastewaters via struvite has been comparatively summarized. Details on the hindrances to nutrient recovery through struvite formation from agricultural effluents, along with strategies to overcome these hindrances, are provided. In addition, various strategies for recovery performance intensification and operational cost reduction are comprehensively discussed. This work will provide scientists and engineers with a better idea on how to solve the bottlenecks of this technique and integrate it successfully into their treatment systems, which will ultimately help close the nutrient loop in agriculture.


Assuntos
Estruvita/química , Águas Residuárias/química , Agricultura , Animais , Fazendas , Nutrientes/química , Solo
9.
Talanta ; 269: 125442, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38029608

RESUMO

Surface-enhanced Raman scattering (SERS) is an important analytical technique. Its detection sensitivity and reproducibility depend on the density and distribution of SERS hotspots. Self-assembly is an efficient method to produce of SERS substrates due to its easy accessibility. However, the assembled defects can hardly be avoided on large area, which could lower the density and uniformity of the hotspots, leading to poor SERS performance. Herein, we report a method to reduce the defects by taking a patterned substrate as template to confine the assembly of Ag nanocubes. The template was prepared based on the combination of photo lithography and self-assembly. Confined by the template, the Ag nanocubes were assembled closely in each dots of the pattern. The limit of detection (LOD) is down to 3.42 × 10-17 M and the enhanced factor (EF) is up to 3.44 × 1010 on the prepared substrate for detecting rhodamine 6G (R6G). In addition, the relative standard deviation (RSD) of the different substrates is 8.75 %. The assembled Ag nanocubes exhibits high sensitivity and reproducibility as SERS substrate, which are contributed by the formation of high-density and uniform hotspots. The prepared substrate can be used for detecting trace amounts of melamine in milk with LOD of 2.06 × 10-7 M and RSD of 6.91 %, so the substrate is applicable for analyzing various analytes.

10.
ACS Sens ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958469

RESUMO

As one of the common carriers of biological information, along with human urine specimens and blood, exhaled breath condensate (EBC) carries reliable and rich information about the body's metabolism to track human physiological normal/abnormal states and environmental exposures. What is more, EBC has gained extensive attention because of the convenient and nondestructive sampling. Facemasks, which act as a physical filter barrier between human exhaled breath and inhaled substances from the external environment, are safe, noninvasive, and economic devices for direct sampling of human exhaled breath and inhaled substances. Inspired by the ability of fog collection of Namib desert beetle, a strategy for in situ collecting and detecting EBC with surface-enhanced Raman scattering is illustrated. Based on the intrinsic and unique wettability differences between the squares and the surrounding area of the pattern on facemasks, the hydrophilic squares can capture exhaled droplets and spontaneously enrich the analytes and silver nanocubes (AgNCs), resulting in good repeatability in situ detection. Using R6G as the probe molecule, the minimal detectable concentration can reach as low as 10-16 M, and the relative standard deviation is less than 7%. This proves that this strategy can achieve high detection sensitivity and high detection repeatability. Meanwhile, this strategy is applicable for portable nitrite analysis in EBC and may provide an inspiration for monitoring other biomarkers in EBC.

11.
J Hazard Mater ; 467: 133689, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38335609

RESUMO

Biodegradable plastic bags (BPBs), meant for eco-friendly, often inadequately degrade in compost, leading to microplastic pollution. In this study, the effect of Fenton-like reaction with Fe3O4 nanoparticles (NMs) on the plastisphere microorganisms' evolution and the BPBs' aging mechanism was revealed by co-composting of food waste with BPBs for 40 days. The establishment of the Fenton-like reaction was confirmed, with the addition of Fenton-like reagent treatments resulting in an increase of 57.67% and 37.75% in H2O2 levels during the composting, compared to the control group. Moreover, the structural characterization reveals that increasing oxygen content continuously generates reactive free radicals on the surface, leading to the formation of oxidative cavities. This process results in random chain-breaking, significantly reducing molecular weights by 39.27% and 38.81%, thus showcasing a deep-seated transformation in the plastic's molecular structure. Furthermore, the microbial network suggested that the Fenton-like reaction enriched plastisphere keystone species, thus accelerating the BPBs' aging. Additionally, the Fenton-like reaction improved compost maturity and reduced greenhouse gas emissions. These results reveal the bio-chemical mechanisms of BPBs aging and random chain-breaking by the Fenton-like reaction, under alternating oxidative/anoxic conditions of composting and provide a new insight to resolve the BPBs' pollutions.


Assuntos
Plásticos Biodegradáveis , Compostagem , Ferro , Eliminação de Resíduos , Alimentos , Peróxido de Hidrogênio , Radicais Livres
12.
Heliyon ; 10(7): e28045, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38590863

RESUMO

HD-Zip (Homeodomain-Leucine Zipper) is a family of transcription factors unique to higher plants and plays a vital role in plant growth and development. Increasing research results show that HD-Zip transcription factors are widely involved in many life processes in plants. However, the HD-Zip transcription factor for cannabis, a valuable crop, has not yet been identified. The sequence characteristics, chromosome localization, system evolution, conservative motif, gene structure, and gene expression of the HD-Zip transcription factor in the cannabis genome were systematically studied. Real-time quantitative polymerase chain reaction (qRT-PCR) was used to verify its function. The results showed that cannabis contained 33 HD-Zip gene members. The number of amino acids is 136-849aa, the isoelectric point is 4.54-9.04, and the molecular weight is 23264.32-93147.87Da. Many cis-acting elements are corresponding to hormone and abiotic stress in the HD-Zip family promoter area of cannabis. Sequencing of the transcriptome at 5 tissue sites of hemp, stems, leaves, bracts, and seeds showed similar levels of expression of 33 members of the HD-Zip gene family at 5 tissue sites. Bioinformatics results show that HD-Zip expression is tissue-specific and may be influenced by hormones and environmental factors. This lays a foundation for further research on the gene function of HD-Zip.

13.
Waste Manag ; 179: 130-143, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38471251

RESUMO

This research conducted an environmental life cycle assessment (LCA) to evaluate an anaerobic digestion-co-pyrolysis (ADCo-Py) system in which pyrolysis was added to traditional food waste (FW) anaerobic digestion (AD) systems to treat the solid fraction and impurities separated from FW. The solid fraction, including impurities such as wooden chopsticks, plastics, eggshells, and bones, is usually incinerated, while pyrolysis can be a viable alternative to optimize FW treatment. The environmental impact of ADCo-Py was compared with stand-alone AD, pyrolysis, and ADCo-INC (AD with incineration of separated solids). The results indicated that both ADCo-Py (-1.726 kg CO2-Eq/kgFW) and ADCo-INC (-1.535 kg CO2-Eq/kgFW) outperform stand-alone AD (-0.855 kg CO2-Eq/kgFW) and pyrolysis (-0.181 kg CO2-Eq/kgFW) in mitigating global warming potential (GWP). Additionally, pretreatments were found to have the most significant influence on GWP, ecotoxicity potential (ETP), and acidification potential (AP). The two-step pretreatment in ADCo-Py, including the separation of solids and drying, significantly improved the environmental sustainability of the system when compared with standalone pyrolysis.


Assuntos
Eliminação de Resíduos , Gerenciamento de Resíduos , Eliminação de Resíduos/métodos , Gerenciamento de Resíduos/métodos , Perda e Desperdício de Alimentos , Dióxido de Carbono , Pirólise , Anaerobiose , Alimentos
14.
Sci Total Environ ; 875: 162356, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36822427

RESUMO

Biodegradable plastic bags (BPBs) to collect food waste and microplastics (MPs) produced from their biodegradation have received considerable scientific attention recently. Therefore, the current study was carried out to assess the co-composting efficiency of biodegradable plastic bags (polylactic acid (PLA) + polybutylene terephthalate (PBAT) + ST20 and PLA + PBAT+MD25) and food waste. The variations in greenhouse gas (GHG) emissions, microbial community and compost fertility were likewise assessed. Compared with the control, PLA + PBAT+ST20 and PLA + PBAT+MD25 both accelerated organic matter degradation and increased temperature. Moreover, PLA + PBAT+ST20 aggravated CH4 and CO2 emissions by 12.10 % and 11.01 %, respectively. PLA + PBAT+MD25 decreased CH4 and CO2 emissions by 5.50 % and 9.12 %, respectively. Meanwhile, compared with PLA + PBAT+ST20, the combined effect of plasticizer and inorganic additive in PLA + PBAT+MD25, reduced the NO3--N contents, seed germination index (GI) and compost maturity. Furthermore, adding BPBs changed the richness and diversity of the bacterial community (Firmicutes, Proteobacteria and Bacteroidetes). Likewise, redundancy analysis (RDA) showed that the co-compost system of BPBs and food waste accelerated significantly bacterial community succession from Firmicutes and Bacteroidetes at the initial stage to Proteobacteria and Actinobacteria at the mature stage, increased co-compost temperature to over 64 °C and extended thermophilic composting phase, and promoted the degradation of MPs. Additionally, according to structural equation model quantification results, the inorganic additive of PLA + PBAT+MD25 had more serious toxicity to microorganisms and had significantly adverse effects on GI through CO2-C (λ = -0.415, p < 0.05) and NO3--N (λ = -0.558, p < 0.001), thus reduced compost fertility and quality. The results also indicated that the BPBs with ST20 as an additive could be more suitable for industrial composting than the BPBs with MD25 as an additive. This study provided a vital basis for understanding the potential environmental and human health risks of the MPs' generated by the degradation of BPBs in compost.


Assuntos
Plásticos Biodegradáveis , Compostagem , Gases de Efeito Estufa , Microbiota , Eliminação de Resíduos , Humanos , Compostagem/métodos , Microplásticos , Dióxido de Carbono , Alimentos , Poliésteres/química , Solo/química
15.
Sci Total Environ ; 904: 166488, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37611705

RESUMO

The black soldier fly (BSF) rearing technology has been a promising bioconversion method for food waste (FW) disposal. However, when used independently, it currently only achieves low efficiency and biomass transformation rates (BTR). This study screened and identified two strains of gut beneficial bacteria, Bacillus cereus and Bacterium YC-LK-LKJ45. The efficiency of a complex culture formulated by these strains was investigated, focusing on enhancing FW reduction and high-value biomass production during the rearing of BSF larvae. The coculture agent group (G1-10%, with two strains in 1:1 volume ratio at a 10 % dosage) exhibited higher larval yield (627.67 g·kg-1), BTR (47.90 %), FW reduction efficiency (80.67 %), and total protein and fat yield (261.99 g·kg-1and 46.24 g·kg-1) compared to the control and the monoculture agent group (which added a single gut beneficial bacteria agent, either Bacillus cereus or Bacterium YC-LK-LKJ45). The bacterial agent altered the richness and diversity of the gut microbial community of BSF, increasing the relative abundance of beneficial bacteria such as Bacillus, Oceano bacillus, and Akkermansia, while decreasing pathogenic bacteria, such as Acinetobacter and Escherichia-Shigella. Structural equation model quantification revealed that α-diversity (λ = 0.897, p < 0.001) and BTR (λ = 0.747, p < 0.001) are crucial drivers for enhancing high-value biomass during bioaugmentation rearing. This investigation provides a theoretical framework for the effective management of food waste using BSF, enhancing its decomposition and transformation into higher-value biomass.


Assuntos
Bacillus , Dípteros , Microbioma Gastrointestinal , Eliminação de Resíduos , Animais , Alimentos , Biomassa , Dípteros/microbiologia , Larva/metabolismo , Bactérias
16.
Gels ; 9(3)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36975639

RESUMO

It remains a big challenge to develop non-precious metal catalysts for oxygen evolution reaction (OER) in energy storage and conversion systems. Herein, a facile and cost-effective strategy is employed to in situ prepare the Ni/Fe oxyhydroxide anchored on nitrogen-doped carbon aerogel (NiFeOx(OH)y@NCA) for OER electrocatalysis. The as-prepared electrocatalyst displays a typical aerogel porous structure composed of interconnected nanoparticles with a large BET specific surface area of 231.16 m2·g-1. In addition, the resulting NiFeOx(OH)y@NCA exhibits excellent OER performance with a low overpotential of 304 mV at 10 mA·cm-2, a small Tafel slope of 72 mV·dec-1, and excellent stability after 2000 CV cycles, which is superior to the commercial RuO2 catalyst. The much enhanced OER performance is mainly derived from the abundant active sites, the high electrical conductivity of the Ni/Fe oxyhydroxide, and the efficient electronic transfer of the NCA structure. Density functional theory (DFT) calculations reveal that the introduction of the NCA regulates the surface electronic structure of Ni/Fe oxyhydroxide and increases the binding energy of intermediates as indicated by the d-band center theory. This work provides a new method for the construction of advanced aerogel-based materials for energy conversion and storage.

17.
Sci Total Environ ; 877: 162779, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36924973

RESUMO

With the outbreak and spread of the COVID-19 epidemic, HCWs are frequently required to wear personal protective equipment (PPE) for nucleic acid sample collection in semi-open transition spaces. Wearing PPE causes significant psychological and physical stress in HCWs. In this study, operative temperature (Top) and wet-bulb globe temperature (WBGT) were used to assess thermal conditions through field experiments, while multiple physiological parameters were measured in the subjects. The results indicated that the subjects showed statistically significant differences in thermal perception and physiological parameters with and without PPE. Using observed increases in heart rate (HR), auditory canal temperature (Tac), mean skin temperature (MST), and end-tidal CO2 pressure, subjects were shown to have an increased metabolic rate and heat storage while wearing PPE. Additionally, a decrease in oxygen concentration was also observed, and this decrease may be linked to fatigue and cognitive impairment. Moreover, HR, MST, and Tac showed a significant linear relationship, which increased with temperature and operative temperature, and the HR response was stronger with PPE than without PPE. The neutral, preferred, and acceptable temperatures were significantly lower with PPE than without PPE, and the deviations for neutral Top/WBGT were 9.5/7.1 °C and preferred Top/WBGT was 2.2/4.0 °C, respectively. Moreover, the upper limits of acceptable WBGT, 29.4 °C with PPE and 20.4 °C without PPE, differed significantly between the two phases. Furthermore, the recorded physiological parameter responses and thermal perception responses of the subjects while wearing PPE indicated that they were at risk of thermal stress. Overall, these results suggest that people who wear PPE should focus on their health and thermal stress. This study provides a reference for the development of strategies to counteract heat stress and improve thermal comfort.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Equipamento de Proteção Individual , Temperatura Cutânea , Estresse Fisiológico , Resposta ao Choque Térmico , Temperatura Alta
18.
Front Neurorobot ; 17: 1253761, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37881516

RESUMO

Introduction: Lumbar puncture is an important medical procedure for various diagnostics and therapies, but it can be hazardous due to individual variances in subcutaneous soft tissue, especially in the elderly and obese. Our research describes a novel robot-assisted puncture system that automatically controls and maintains the probe at the target tissue layer through a process of tissue recognition. Methods: The system comprises a robotic system and a master computer. The robotic system is constructed based on a probe consisting of a pair of concentric electrodes. From the probe, impedance spectroscopy measures bio-impedance signals and transforms them into spectra that are communicated to the master computer. The master computer uses a Bayesian neural network to classify the bio-impedance spectra as corresponding to different soft tissues. By feeding the bio-impedance spectra of unknown tissues into the Bayesian neural network, we can determine their categories. Based on the recognition results, the master computer controls the motion of the robotic system. Results: The proposed system is demonstrated on a realistic phantom made of ex vivo tissues to simulate the spinal environment. The findings indicate that the technology has the potential to increase the precision and security of lumbar punctures and associated procedures. Discussion: In addition to lumbar puncture, the robotic system is suitable for related puncture operations such as discography, radiofrequency ablation, facet joint injection, and epidural steroid injection, as long as the required tissue recognition features are available. These operations can only be carried out once the puncture needle and additional instruments reach the target tissue layer, despite their ensuing processes being distinct.

19.
Environ Technol ; 44(18): 2781-2794, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35188433

RESUMO

The addition of carbonaceous materials into anaerobic digestion (AD) has gained widespread attention due to their significant effects on anaerobic performance and antibiotic resistance gene (ARG) removal. This study selected graphite, graphene, and graphene oxide (GO) as additives to investigate variations in AD performance, ARG removal, microbial community diversity and structure in wet AD systems. The results indicated that the addition of graphite-based materials in wet AD systems could increase degradation of solid organic matters by 0.91%-3.41% and utilization of soluble organic fractions by 10.43%-13.67%, but could not stimulate methane production. After the addition of graphite and graphene, ARG removal rates were effectively increased to 90.85% and 94.22%, respectively. However, the total ARG removal rate was reduced to 77.46% with the addition of GO. In addition, the microbial diversity in the wet AD process was enhanced with the addition of GO only, graphite and graphene led to a reduction in it. As for bacterial community, graphite and graphene increased the abundance of Thermotogae from 43.43% to 57.42% and 58.74%, while GO increased the abundance of Firmicute from 49.90% to 56.27%. For the archaeal community, the proportion of hydrogenotrophic methanogens was improved when adding each graphite-based material; however, only GO increased Methanosaeta that was acetoclastic methanogens. Finally, methanogens were found as the ARG host, and ARGs that belong to the same subtype might exist in the same host bacteria.


Assuntos
Grafite , Microbiota , Anaerobiose , Antibacterianos/farmacologia , Bactérias/genética , Resistência Microbiana a Medicamentos/genética , Microbiota/genética , Metano
20.
Int J Nurs Sci ; 10(2): 268-275, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37128479

RESUMO

Objectives: To analyze and summarize the research hotspots and advancement of post-traumatic growth (PTG) over the past 15 years based on co-word analysis of keywords, and provide references for PTG-related research and clinical intervention. Methods: All studies related to PTG were retrieved from PubMed and Web of Science (WOS) from January 2013 to July 2022. A total of 11 Medical Subject Headings (MeSH) and keywords were used to identify qualified studies. Bibliographic Item Co-occurrence Matrix Builder (BICOMB; version 2.0) was used to conduct high-frequency keywords extraction and matrix setup, Graphical Clustering Toolkit (gCLUTO; version 1.0) was employed to perform clustering analysis, and SPSS (version 25.0) was used to carry out strategic diagram analysis. Results: A total of 2,370 publications were selected, from which 38 high-frequency keywords were extracted. The results revealed six research hotspots on PTG during the period from 2013 to 2022, including research on i) emotional reactions after negative life events, ii) PTG among cancer survivors, iii) rumination and resilience after trauma, iv) PTG among children and adolescents, v) role of social support and coping strategy in PTG, and vi) association between PTG and quality of life. Conclusions: This co-word analysis effectively reveals an overview of PTG over the past 15 years. The six research categories deduced from this study can reflect that the research content in the field of PTG is abundant, but some research topics have not yet been mature. The findings of this study are of great value to future investigations associated with PTG.

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