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1.
ACS Appl Mater Interfaces ; 16(19): 24572-24579, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38690767

RESUMO

Infrared (IR) solar cells, capable of converting low-energy IR photons to electron-hole pairs, are promising optoelectronic devices by broadening the utilization range of the solar spectrum to the short-wavelength IR region. The emerging PbS colloidal quantum dot (QD) IR solar cells attract much attention due to their tunable band gaps in the IR region, potential multiple exciton generation, and facile solution processing. In PbS QD solar cells, ZnO is commonly utilized as an electron transport layer (ETL) to establish a depleted heterostructure with a QD photoactive layer. However, band gap shrinkage of large PbS QDs makes it necessary to tailor the behaviors of the ZnO ETL for efficient carrier extraction in the devices. Herein, the characteristics of ZnO ETL are efficiently and flexibly tailored to match the QD layer by handily adjusting the postannealing process of ZnO ETL. With a suitable temperature, the well-matched energy level alignment and suppressed trap states are simultaneously achieved in the ZnO ETL, effectively reducing the nonradiative recombination and accelerating the electron injection from the QD layer to ETL. As a consequence, a high-performance PbS QD photovoltaic device with power conversion efficiencies (PCEs) of 10.09% and 1.37% is obtained under AM 1.5 and 1100 nm filtered solar illumination, demonstrating a simple and effective approach for achieving high-performance IR photoelectric devices.

2.
Molecules ; 29(7)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38611708

RESUMO

In this study, the separation conditions of UHPLC-QTOF-MS and the extraction conditions of QuEChERS were optimized. The analytical process for determining Broflanilide residues in different soil types was successfully established and applied to its adsorption, desorption, and leaching in soil. Broflanilide was extracted from soil with acetonitrile and purified using PSA and MgSO4. The modified UHPLC-QTOF-MS method was used for quantification. The average recovery of Broflanilide was between 87.7% and 94.38%, with the RSD lower than 7.6%. In the analysis of adsorption, desorption, and leaching quantities in four soil types, the RSD was less than 9.2%, showing good stability of the method, which can be applied to determine the residue of Broflanilide in different soils.

3.
BMC Public Health ; 24(1): 460, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355487

RESUMO

BACKGROUND: The COVID-19 pandemic has imposed unprecedented stress and challenges upon medical staff, potentially resulting in posttraumatic growth (PTG). This scoping review aims to synthesize the existing knowledge on PTG among medical staff during the pandemic by identifying its current status and potential influencing factors. The findings may provide a foundation for future research and interventions to enhance the medical staff's psychological resilience and well-being. METHODS: Literature was systematically searched on PTG among medical staff during the COVID-19 pandemic from 01 January 2020 to 31 December 2022. The following databases were searched: PubMed, Web of Science, Embase, CINAHL, PsycINFO, Cochrane Library, China National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature Service System (SinoMed), and Wanfang Data. Eligibility criteria included: (1) medical staff as research subjects; (2) a focus on "posttraumatic growth" or "alternative posttraumatic growth" related to the COVID-19 outbreak and pandemic; (3) discussion of the situation and influencing factors of PTG; and (4) study types, such as qualitative, quantitative, and mixed methods. Two researchers independently selected and extracted study characteristics (study design, study population, region, measurement instruments, and primary outcomes) from the included literature. The data were synthesized qualitatively and descriptively. RESULTS: Thirty-six papers from 12 countries met the inclusion criteria. Moderate PTG levels were observed among healthcare workers during the COVID-19 pandemic, with emphasis on "interpersonal relationships," "changes in life philosophy," and "growth in personal competence." Influencing factors included trauma exposure, sociodemographics, psychological characteristics (resilience and positive qualities), coping, and social support. CONCLUSIONS: This review discovered moderate PTG levels among medical staff during the COVID-19 pandemic, with critical areas in interpersonal relationships, life philosophy, and personal competence. The identified influencing factors can inform future research and interventions to enhance healthcare workers' psychological resilience and well-being.


Assuntos
COVID-19 , Crescimento Psicológico Pós-Traumático , Resiliência Psicológica , Humanos , Pandemias , Corpo Clínico
4.
J Ethnopharmacol ; 328: 117993, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38423408

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Alzheimer's disease (AD) is a multi-factorial degenerative disease, and multi-targeted therapies targeting multiple pathogenic mechanisms should be explored. Shenghui decoction (SHD) is an ancient traditional Chinese medicine (TCM) formula used clinically to alleviate AD. However, the precise mechanism of action of SHD as a therapeutic agent for AD remains unclear. AIM OF THE STUDY: This study investigated the neuroprotective properties and potential mechanisms of action of SHD in mitigating AD-like symptoms induced by AlCl3 in a zebrafish model. MATERIALS AND METHODS: Active components of SHD were detected using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Zebrafish were exposed to AlCl3 (200 µg/L) for 30 days to establish an AD zebrafish model. AlCl3-exposed zebrafish were treated with SHD or donepezil. Behavioral tests were used to assess learning and memory, locomotor activity, and AD-related anxiety and aggression in AlCl3-exposed zebrafish. Nissl staining and transmission electron microscopy were used to evaluate histological alterations in brain neurons. The concentrations of pro-inflammatory cytokines (tumor necrosis factor-α, TNF-α; interleukin-1ß, IL-1ß) were quantified using Enzyme-linked immunosorbent assay (ELISA). Markers of oxidative stress and cholinergic activity (acetylcholinesterase, AChE) were detected using biochemical assays. Western blotting and immunofluorescence were used to detect the protein expression levels of Aß, p-tau, PSD-95, synaptophysin, TLR4, phosphorylation of NF-κB p65, p38, and JNK. RESULTS: Fifteen SHD compounds were identified by UPLC-MS/MS analysis. SHD improved AlCl3-induced dyskinesia, learning and memory impairment, anxiety-like behavior, and aggressive behavior in zebrafish. AlCl3-exposed zebrafish showed AD-like pathology, overexpression of Aß, hyperphosphorylated tau protein, marked neuronal damage, decreased expression of synaptic proteins, synaptophysin, and PSD-95, and impairment of synaptic structural plasticity. These effects were reversed by the SHD treatment. We also observed that SHD ameliorated oxidative stress and decreased AChE activity and inflammatory cytokine levels. These effects are similar to those observed for donepezil. Meanwhile, SHD could decrease the protein expression of TLR4 and inhibit phosphorylation of NF-κB, JNK, and p38 MAPK. These results demonstrate that SHD has the potential to exert neuroprotective effects, which may be partly mediated via inhibition of the JNK/p38 MAPK signaling pathway. CONCLUSIONS: Our findings revealed the therapeutic mechanism of SHD in mitigating AD progression and suggested that SHD is a potent neuroprotectant that contributes to the future development of TCM modernization and broader clinical applications.


Assuntos
Doença de Alzheimer , Fármacos Neuroprotetores , Animais , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peixe-Zebra , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Fármacos Neuroprotetores/química , Donepezila/uso terapêutico , Sinaptofisina/metabolismo , NF-kappa B/metabolismo , Acetilcolinesterase/metabolismo , Cromatografia Líquida , Receptor 4 Toll-Like/metabolismo , Espectrometria de Massas em Tandem , Citocinas/metabolismo , Sistema de Sinalização das MAP Quinases , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
5.
Opt Lett ; 48(21): 5563-5566, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37910703

RESUMO

The applications of two-dimensional transition metal carbide/nitride (MXene) in the fields of optoelectronics, sustainable energy, and sensors, among others, have been broadly investigated due to their special electrical, optical, and structural properties. In this Letter, MXene (Ti3C2Tx) has been firstly, to the best of our knowledge, adopted for the application of a photoacoustic transducer by taking advantage of the photothermal property. The efficiency of the photoacoustic transducer based on a sandwich structure of glass/MXene/polydimethylsiloxane (PDMS) has been experimentally demonstrated to be 1.25 × 10-2 by converting laser pulses into ultrasonic waves, generating a high acoustic pressure of 15.7 MPa without additional acoustic focusing. That can be explained by the great light absorption and photothermal conversion of the Ti3C2Tx layer.

6.
Nanomaterials (Basel) ; 13(19)2023 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-37836364

RESUMO

Perovskite quantum dots (QDs), emerging with excellent bright-green photoluminescence (PL) and a large absorption coefficient, are of great potential for the fabrication of light sources in underwater optical wireless communication systems. However, the instability caused by low formation energy and abundant surface traps is still a major concern for perovskite-based light sources in underwater conditions. Herein, we propose ultra-stable zero dimensional-two dimensional (0D-2D) CsPbBr3 QD/1,4-bis(4-methylstyryl)benzene (p-MSB) nanoplate (NP) heterostructures synthesized via a facile approach at room temperature in air. CsPbBr3 QDs can naturally nucleate on the p-MSB NP toluene solution, and the radiative combination is drastically intensified owing to the electron transfer within the typical type-II heterostructures, leading to a sharply increased PLQY of the heterostructure thin films up to 200% compared with the pristine sample. The passivation of defects within CsPbBr3 QDs can be effectively realized with the existence of p-MSB NPs, and thus the obviously improved PL is steadily witnessed in an ambient atmosphere and thermal environment. Meanwhile, the enhanced humidity stability and a peak EQE of 9.67% suggests a synergetic strategy for concurrently addressing the knotty problems on unsatisfied luminous efficiency and stability of perovskites for high-performance green-emitting optoelectronic devices in underwater applications.

7.
Sensors (Basel) ; 23(10)2023 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-37430652

RESUMO

Reconstruction of the acoustic relaxation absorption curve is a powerful approach to ultrasonic gas sensing, but it requires knowledge of a series of ultrasonic absorptions at various frequencies around the effective relaxation frequency. An ultrasonic transducer is the most widely deployed sensor for ultrasonic wave propagation measurement and works only at a fixed frequency or in a specific environment like water, so a large number of ultrasonic transducers operating at various frequencies are required to recover an acoustic absorption curve with a relative large bandwidth, which cannot suit large-scale practical applications. This paper proposes a wideband ultrasonic sensor using a distributed Bragg reflector (DBR) fiber laser for gas concentration detection through acoustic relaxation absorption curve reconstruction. With a relative wide and flat frequency response, the DBR fiber laser sensor measures and restores a full acoustic relaxation absorption spectrum of CO2 using a decompression gas chamber between 0.1 and 1 atm to accommodate the main molecular relaxation processes, and interrogates with a non-equilibrium Mach-Zehnder interferometer (NE-MZI) to gain a sound pressure sensitivity of -45.4 dB. The measurement error of the acoustic relaxation absorption spectrum is less than 1.32%.

8.
Neuroreport ; 34(11): 566-574, 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37384937

RESUMO

Sleep deprivation impairs learning and memory. The neuroprotective function of ginsenoside Rg1 (Rg1) has been reported. This study aimed to investigate the alleviative effect and underlying mechanism of action of Rg1 on learning and memory deficits induced by sleep deprivation. Using 72 h of LED light to establish sleep deprivation model and treatment with Rg1-L (0.5 mg/ml), Rg1-H (1 mg/ml), and melatonin (positive control, 0.25 mg/ml), we investigated the behavioral performance of sleep deprivation zebrafish through 24 h autonomous movement tracking, a novel tank diving test, and a T-maze test. Brain injuries and ultrastructural changes were observed, brain water content was measured, and apoptotic events were analyzed using terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling staining. The oxidation-associated biomarkers superoxide dismutase, catalase, and glutathione peroxidase activity and lipid peroxidation product malondialdehyde content were detected. Real-time PCR and western blotting were performed to detect the levels of apoptotic molecules (Bax, caspase-3, and Bcl-2). Rg1-treatment was observed to improve the behavioral performance of sleep-deprivation fish, alleviate brain impairment, and increase oxidative stress-related enzyme activity. Rg1 can effectively exhibit neuroprotective functions and improve learning and memory impairments caused by sleep deprivation, which could be mediated by the Bcl-2/Bax/caspase-3 apoptotic signaling pathway (see Supplementary Video Abstract, Supplemental digital content, http://links.lww.com/WNR/A702 which demonstrates our research objectives, introduction overview of Rg1, and main direction of future research).


Assuntos
Privação do Sono , Peixe-Zebra , Animais , Caspase 3 , Privação do Sono/complicações , Privação do Sono/tratamento farmacológico , Proteína X Associada a bcl-2 , Apoptose , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/etiologia , Aprendizagem em Labirinto
9.
Front Endocrinol (Lausanne) ; 14: 1167317, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37251666

RESUMO

Introduction: Existing evidence suggests an association between certain vitamins and metabolic syndrome (MetS), but few epidemiological studies have focused on the effects of multivitamin co-exposure on MetS. This study aims to investigate the associations of the individual or multiple water-soluble vitamins (i.e., vitamin C (VC), vitamin B9 (VB9), and vitamin B12 (VB12)) with co-exposure to MetS, as well as the dose-response relationships among them. Methods: A cross-sectional study was conducted by employing the National Health and Examination Surveys (NHANESs) 2003-2006. Multivariate-adjusted logistic regression models were used to explore the association between individual serum water-soluble vitamins and the risk of MetS and its components, including waist circumference, triglyceride, high-density lipoprotein, blood pressure, and fasting plasma glucose. Restricted cubic splines were performed to explore the dose-response relationships among them. The quantile g-computation method was adopted to explore the associations of multiple water-soluble vitamins co-exposure with MetS risk and MetS components. Results: A total of 8983 subjects were involved in the study, of whom 1443 were diagnosed with MetS. The MetS groups had a higher proportion of participants with age ≥60 years, BMI ≥30 kg/m2, and insufficient physical activity. Compared with the lowest quartile, the third (OR=0.67, 95% CI: 0.48, 0.94) and highest quartiles (OR=0.52, 95%CI: 0.35, 0.76) of VC were associated with lower MetS risk. Restricted cubic splines showed negative dose-response relationships among VC, VB9 and VB12, and MetS. Regarding MetS components, higher VC quartiles were associated with lower waist circumference, triglyceride, blood pressure, and fasting plasma glucose, while higher VC and VB9 quartiles were associated with higher high-density lipoprotein (HDL). Co-exposure to VC, VB9, and VB12 was significantly inversely associated with MetS, with ORs (95% CI) of 0.81 (0.74, 0.89) and 0.84 (0.78, 0.90) in the conditional and marginal structural models, respectively. Furthermore, we found that VC, VB9, and VB12 co-exposure were negatively associated with waist circumference and blood pressure, while VC, VB9, and VB12 co-exposure were positively associated with HDL. Conclusion: This study revealed negative associations of VC, VB9, and VB12 with MetS, while the high water-soluble vitamin co-exposure was associated with a lower MetS risk.


Assuntos
Síndrome Metabólica , Humanos , Pessoa de Meia-Idade , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/etiologia , Inquéritos Nutricionais , Estudos Transversais , Glicemia/metabolismo , Índice de Massa Corporal , Vitaminas , Ácido Fólico , Vitamina B 12 , Triglicerídeos , Lipoproteínas HDL , Água
10.
Am J Infect Control ; 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37059121

RESUMO

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) has been increasingly used in China, but nosocomial infections (NI) in patients receiving ECMO remain poorly characterized. Thus, this study aimed to investigate the incidence rate, causative was pathogens, and risk factors of NIs in ECMO patients. METHODS: A retrospective cohort study of patients receiving ECMO between January 2015 and October 2021 was conducted in a tertiary hospital. General demographics and clinical data of the included patients were collected from the electronic medical record system and the real-time NI surveillance system. RESULTS: A total of 86 infected patients with 110 episodes of NIs were identified in 196 patients receiving ECMO. The incidence of NI was 59.2/1000 ECMO days. The median time for the first NI in ECMO patients was 5 days (interquartile range: 2-8 days). Hospital-acquired pneumonia and bloodstream infections were common types of NIs in ECMO patients, and the main pathogens were gram-negative bacteria. Pre-ECMO invasive mechanical ventilation (OR = 2.40, 95% CI:1.12-5.15) and prolonged duration of ECMO (OR = 1.26, 95% CI:1.15-1.39) were risk factors for NIs during ECMO support. DISCUSSION: This study identified the main infection sites and pathogens of NIs in ECMO patients. Although NIs may not affect successful ECMO weaning, additional measures should be implemented to reduce the incidence of NI during ECMO support.

11.
Waste Manag ; 163: 12-21, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36989826

RESUMO

Co-pyrolysis is a potentially effective method for both biomass waste management and multi-functional biochar-based product design. It involves the thermochemical decomposition of biomass waste under anoxic conditions, which can reduce the cost of disposal and produce biochar with beneficial properties. Herein, this study aimed to investigate the properties and environmental applications of biochar from single- and mixed- feedstocks of wheat straw, rice husk, pig manure, and oyster shell at 450 ℃, respectively. A pot experiment with Chinese cabbage was carried out to compare the effects of biochars with limestone on soil Cd and Pb immobilization at two harvest periods. The results indicated that co-pyrolysis of various biomasses exhibited synthetic effects on promoting the calorific value of syngas and enhancing the quality of produced biochar. The pot experiment revealed a significant promotion on soil pH, soil organic matter, cation exchange capacity, and soluble Ca, which consequently reduced Cd and Pb availability. In contrast with limestone treatment, soil amendment with single biomass-derived and co-pyrolysis-derived (COPB) biochars had a significant positive impact on soil fertility and microbial biomass. Application of COPB at a 0.5% dosage consistently and most effectively enhanced the shoot biomass, increased leaf Vitamin C content but reduced leaf content of nitrate and heavy metals in both harvests. Using COPB for soil remediation would be financially visible due to the enhancement of crop yield. Therefore, this study proposes a strategy for targeted enhancement of the functions of biochar derived from co-pyrolysis of selected biomass waste for soil remediation and agricultural production.


Assuntos
Metais Pesados , Oryza , Poluentes do Solo , Animais , Suínos , Cádmio , Pirólise , Chumbo , Poluentes do Solo/análise , Metais Pesados/análise , Carvão Vegetal/química , Solo/química , Oryza/química
12.
Discov Nano ; 18(1): 11, 2023 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-36780122

RESUMO

Photodetectors (PDs) suffer from dark current due to defects in the perovskite photosensitive layer. Contact between the photosensitive layer and carbon electrodes could result in recombination of carriers at the interface. In this work, CsPbI3 quantum dots (QDs) were added between the photosensitive layer and the carbon electrode as the interfacial layer to passivate the surface defects of perovskite layer and improve the energy level matching at the interface. The effect of QDs concentrations on the passivation of the perovskite layer was investigated. It was found that the photoluminescence intensity of perovskite films was the strongest and the decay lifetime was the longest when the QDs concentration was 3 mg/mL. Owing to QDs passivation, the dark current of perovskite PD decreased by 94% from [Formula: see text] to [Formula: see text] A. The responsivity (R) at 605 nm improved by 27% from 0.29 to 0.37 A/W at 0 V bias voltage. The specific detectivity (D*) increased by 420% from [Formula: see text] to [Formula: see text] Jones.

13.
Sensors (Basel) ; 23(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36772761

RESUMO

In this paper, a variety of 2D materials on the surface plasmon resonance sensor based on Al-Ni bimetallic layer are compared. Simulation results indicate that lateral position shift, which is calculated according to the real and imaginary parts of the refractive index of material, can be used as an effective parameter to optimize the sensitivity. By using the parameters for optimizing the SPR structures, the results show that the multiple layer models of Al(40 nm)-Ni(22 nm)-black phosphorus (BP)(1 L) and Al(40 nm)-Ni(22 nm)-blue phosphorus (BlueP)/WS2(1 L) exhibit average angular sensitivities of 507.0 °/RIU and 466 °/RIU in the refractive index range of 1.330-1.335, and maximum sensitivity of 542 °/RIU and 489 °/RIU at the refractive index of 1.333, respectively. We expect more applications can be explored based on the highly sensitive SPR sensor in different fields of optical sensing.

14.
Opt Express ; 30(24): 42875-42891, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36522998

RESUMO

In this paper, modal interference discrepancy in an all-fiber MZI is theoretically analyzed and experimentally verified. Theoretical analysis demonstrates that ambient refractive index (RI) response of core-cladding modal interference in an all-fiber MZI is blue-shift, while that of cladding-cladding modal interference is red-shift. Temperature response trends of the two kinds of modal interference are uniformly red-shift. The discrepancy is used to fabricate an improved Vernier sensor which is cascaded by two unit MZIs. One MZI is slightly core-offset fused to obtain core-cladding modal interference, and the other is obviously offset fused to get cladding-cladding modal interference. Ambient RI sensitivity of the cascaded sensor is improved with temperature cross-talk restrained. Ambient RI responses of the two unit MZIs are measured to be opposite, which are -54.009 nm/RIU (within RI range of 1.3362∼1.3811) for the slight and 142.581 nm/RIU for the obvious offset unit MZI. While, temperature response trends of them are consistent, which are 0.042 nm/°C for the slight and 0.025 nm/°C for the obvious offset unit MZI, respectively. For the cascaded Vernier sensor ambient RI sensitivity reaches -1788.160 nm/RIU, which is 33.1 and 12.5 folds improved over the two unit MZIs, respectively. Temperature sensitivity of the cascaded sensor is as low as 0.167 nm/°C and only causes a slight RI error of 9.339 × 10-5 RIU/°C. Due to the simple structure, ease of fabrication, and low temperature cross-talk, the modal interference discrepancy-based Vernier sensor is believed to have potential application prospects in biochemical sensing fields.

15.
Nanomaterials (Basel) ; 12(23)2022 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-36500840

RESUMO

Two-dimensional (2D) organic-inorganic perovskites have great potential for the fabrication of next-generation photodetectors owing to their outstanding optoelectronic features, but their utilization has encountered a bottleneck in anisotropic carrier transportation induced by the unfavorable continuity of the thin films. We propose a facile approach for the fabrication of 0D ZnO quantum dot (QD)/2D (PEA)2PbI4 nanosheet hybrid photodetectors under the atmospheric conditions associated with the ZnO QD chloroform antisolvent. Profiting from the antisolvent, the uniform morphology of the perovskite thin films is obtained owing to the significantly accelerated nucleation site formation and grain growth rates, and ZnO QDs homogeneously decorate the surface of (PEA)2PbI4 nanosheets, which spontaneously passivate the defects on perovskites and enhance the carrier separation by the well-matched band structure. By varying the ZnO QD concentration, the Ion/Ioff ratio of the photodetectors radically elevates from 78.3 to 1040, and a 12-fold increase in the normalized detectivity is simultaneously observed. In addition, the agglomeration of perovskite grains is governed by the annealing temperature, and the photodetector fabricated at a relatively low temperature of 120 °C exhibits excellent stability after a 50-cycle test in the air condition without any encapsulation.

16.
Appl Opt ; 61(17): 5055-5061, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-36256183

RESUMO

The acousto-optic interaction is strongly modified and different in subwavelength confinement. Here, the optical propagation and acoustic propagation in a subwavelength-diameter fiber (SDF) have been investigated through adopting a two-layer fiber model of air-coated silica rod. Theoretical investigation indicates that SDF with a diameter below 1.2 µm supports the single mode of light propagation, and various Brillouin acoustic modes with well-spaced spectral distribution can be also excited. Due to the light propagation with the outer environment as the cladding layer, the surrounding medium will greatly affect Brillouin scattering of SDFs. Both the simulation and experiment results indicate a relatively good linear relationship between the Brillouin frequency shift of the lower acoustic modes and surrounding environmental refractive index (RI), and the higher RI sensitivity in finer SDFs can be obtained. In addition, hybrid acoustic waves have shown higher sensitivity and stability than surface acoustic modes. A RI sensitivity of about 5.1 GHz/RIU has been achieved in a 1.1 µm SDF, demonstrating its potential application in RI sensing.

17.
Contrast Media Mol Imaging ; 2022: 6057115, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935331

RESUMO

Tracheal intubation is an important access to general anesthesia surgery or respiratory support in critically ill patients. Orotracheal intubation is the most common method of establishing artificial airways in clinical practice. Tracheal intubation and mechanically assisted breathing are among the important steps in the clinical rescue of critically ill patients. During tracheal intubation, it easily causes iatrogenic skin damage, unclear mouth, ulcer, and other oral mucosal complications due to the improper fixation method and excellent dental pads. Therefore, the purpose of this study was to design a novel oral suction device for patients with orotracheal intubation and explore its safety, convenience, and comfort in the clinical application of orotracheal intubation patients. From October 2016 to April 2017, a total of 232 patients with mechanical ventilation through orotracheal intubation in the Department of Surgery and Critical Care Medicine were selected by the convenience sampling method. According to the random number table method, 232 cases were divided into the experimental group and control group, with 116 cases in each group. The experimental group used a self-designed oral fluid suction device to fix the tracheal intubation; the control group used the traditional method, placing ordinary disposable tooth pads, and then using 3M tape to fix the tracheal intubation. The incidence of oral mucosa and lip pressure ulcers, patient comfort, and tracheal tube displacement were observed and compared between the two groups. The incidence of oral mucosa and lip pressure ulcers in the observation group using the self-designed oral fluid suction device to fix the tracheal intubation was significantly lower than that in the control group. At the same time, the comfort of the patients was significantly higher than that of the control group, the incidence of tracheal tube displacement was significantly lower than that of the control group, and the differences between the above indicators were statistically significant (P < 0.05). For patients with orotracheal intubation, using a new oral fluid suction device to fix the tracheal intubation can effectively prevent the displacement of the tracheal intubation, protect the oral mucosa and lips, and reduce the pain of the patient. At the same time, the oral fluid suction device designed in this study has low production cost, strong practicability, and is suitable for clinical promotion.


Assuntos
Estado Terminal , Úlcera por Pressão , Humanos , Intubação Intratraqueal/métodos , Respiração Artificial/métodos , Sucção
18.
Front Microbiol ; 13: 831746, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35495701

RESUMO

Microbial communities of soil aggregate-size fractions were explored with molecular and networking assays for topsoil samples from a clayey rice paddy under long-term fertilization treatments. The treatments included no fertilizer (NF) as control, chemical fertilizer only (CF), chemical fertilizer with swine manure (CFM), and chemical fertilizer with rice straw return (CFS). Following a wet-sieving protocol, water-stable aggregates were separated into size fractions of large macroaggregates (L-MacA, >2,000 µm), macroaggregates (MacA, 2,000-250 µm), microaggregates (MicA, 250-53 µm), fine microaggregates (F-MicA, 53-2 µm), and fine clay (F-Clay, <2 µm). Mass proportion was 32.3-38.2% for F-MicA, 23.0-31.5% for MacA, 19.0-23.1% for MicA, 9.1-12.0% for L-MacA, and 4.9-7.5% for F-Clay, respectively. The proportion of MacA was increased, but F-Clay was reduced by fertilization, whereas the mean weight diameter was increased by 8.0-16.2% from 534.8 µm under NF to 621.5 µm under CFM. Fertilization affected bacterial 16S rRNA and fungal 18S rRNA gene abundance in F-MicA and F-Clay but not in aggregates in size larger than 53 µm. However, bacterial and fungal community α-diversities and community structures were quite more divergent among the fertilization treatments in all size fractions. Organic carbon and gene abundance of bacteria and fungi were enriched in both L-MacA and MacA but depleted in F-Clay, whereas microbial Shannon diversity was rarely changed by fraction size under the four treatments. L-MacA and MacA contained more bacteria of r-strategists and copiotrophs, whereas F-MicA and F-Clay were demonstrated with a higher abundance of K-strategists and oligotrophs. Guilds of parasitic and litter saprotrophic fungi were enriched in F-MicA but depleted in L-MacA. Furthermore, most of bacterial and fungal operational taxonomic units were strongly interacted in L-MacA and MacA rather than in MicA and F-Clay. Thus, MacA acted as micro-hotspots enriched with functional and networked microbial communities, which were enhanced with organic/inorganic fertilization in the rice paddy.

19.
Diabetes Metab Syndr Obes ; 14: 4015-4030, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34552341

RESUMO

Hyperlipidemia is a disorder of lipid metabolism, which is a major cause of coronary heart disease. Although there has been considerable progress in hyperlipidemia treatment, morbidity and risk associated with the condition continue to rise. The first-line treatment for hyperlipidemia, statins, has multiple side effects; therefore, development of safe and effective drugs from natural products to prevent and treat hyperlipidemia is necessary. Diosgenin is primarily derived from fenugreek (Trigonella foenum graecum) seeds, and is also abundant in medicinal herbs such as Dioscorea rhizome, Dioscorea septemloba, and Rhizoma polygonati, is a well-known steroidal sapogenin and the active ingredient in many drugs to treat cardiovascular conditions. There is abundant evidence that diosgenin has potential for application in correcting lipid metabolism disorders. In this review, we evaluated the latest evidence related to diosgenin and hyperlipidemia from clinical and animal studies. Additionally, we elaborate the pharmacological mechanism underlying the activity of diosgenin in treating hyperlipidemia in detail, including its role in inhibition of intestinal absorption of lipids, regulation of cholesterol transport, promotion of cholesterol conversion into bile acid and its excretion, inhibition of endogenous lipid biosynthesis, antioxidation and lipoprotein lipase activity, and regulation of transcription factors related to lipid metabolism. This review provides a deep exploration of the pharmacological mechanisms involved in diosgenin-hyperlipidemia interactions and suggests potential routes for the development of novel drug therapies for hyperlipidemia.

20.
ACS Appl Mater Interfaces ; 13(30): 35972-35980, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34289689

RESUMO

The dilemma of harvesting fugacious photons by photoactive nanomaterials of limited absorption volume fundamentally hinders the photodetection at relatively lower light intensities. To address the insufficient light utilization efficiency, spatial light confinement becomes an effective and promising approach. High-performance ultraviolet (UV) photodetectors based on the self-assembled Au nanoparticle/ZnO honeycomb nano-mesh (Au NP/ZnO HN) are demonstrated through a facile solution-processed method on anodized aluminum oxide (AAO) membranes. The congregated geometry of the self-assembled ZnO HNs is well-defined by the AAO matrixes, which also effectively collects the transmitted light beams back to the photoactive layers. Benefiting from surface plasmon resonance, the enhanced absorption of the ZnO HNs is eventually obtained via the recursive light utilization between Au NPs and AAO matrixes as a function of AAO pore diameters (DAAO). With a systematic control of the photodetector configurations, an optimal performance is obtained with growth duration of the ZnO HNs for 40 min on the AAO substrates (DAAO = 100 nm), and an excellent responsivity of 23.4 A/W is witnessed even under a relatively low light intensity of 0.4 mW/cm2, providing a novel route to realize high-performance UV photodetection under low-power illumination.

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