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1.
Artigo em Inglês | MEDLINE | ID: mdl-38577956

RESUMO

BACKGROUND: The behavioral manifestations and neurophysiological responses to sedation can assist in understanding brain function after neurological damage, and can be described by cortical functional connectivity. Glioma patients may experience neurological deficits that are not clinically detectable before sedation. We hypothesized that patients with gliomas exhibit distinct cortical connectivity patterns compared to non-neurosurgical patients during sedation. METHODS: This is a secondary analysis of a previously published prospective observational study. Patients scheduled for resection of supratentorial glioma (n=21) or a non-neurosurgical procedure (n=21) under general anesthesia were included in this study. Frontal electroencephalography (EEG) signals were recorded at different sedation levels as assessed by the Observer Assessment of Alertness/Sedation (OAA/S) score. Kernel principal component analysis and k-means clustering were used to determine possible temporal dynamics from the weighted phase lag index characteristics. RESULTS: Ten EEG connectivity states were identified by clustering (76% consistency), each with unique properties. At OAA/S 3, the median (Q1, Q3) occurrence rates of state 6 (glioma group, 0.110 [0.083, 0.155] vs. control group, 0.070 [0.030, 0.110]; P=0.008) and state 7 (glioma group, 0.105 [0.083, 0.148] vs. control group: 0.065 [0.038, 0.090]; P=0.001), which are dominated by beta connectivity, were significantly different between the 2 groups, reflecting differential conversion of the beta band between the left and right brain regions. In addition, the temporal dynamics of the brain's functional connectivity was also reflected in the transition relationships between metastable states. CONCLUSIONS: There were differences in EEG functional connectivity, which is dynamic, between the glioma and nonglioma groups during sedation.

2.
Fish Shellfish Immunol ; 149: 109555, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38615703

RESUMO

Developing a low-protein feed is important for the sustainable advancement of aquaculture. The aim of this study was to investigate the effects of essential amino acid (EAA) supplementation in a low-protein diet on the growth, intestinal health, and microbiota of the juvenile blotched snakehead, Channa maculata in an 8-week trial conducted in a recirculating aquaculture system. Three isoenergetic diets were formulated to include a control group (48.66 % crude protein (CP), HP), a low protein group (42.54 % CP, LP), and a low protein supplementation EAA group (44.44 % CP, LP-AA). The results showed that significantly lower weight gain (WG), specific growth rate (SGR), protein efficiency ratio (PER), and feed efficiency ratio (FER) were observed in fish that were fed LP than in the HP and LP-AA groups (P < 0.05). The HP and LP-AA groups exhibited a significant increase in intestinal villus length, villus width, and muscular thickness compared to the LP group (P < 0.05). Additionally, the HP and LP-AA groups demonstrated significantly higher levels of intestinal total antioxidant capacity (T-AOC), catalase (CAT), and superoxide dismutase (SOD) and lower levels of malondialdehyde (MDA) compared to the LP group (P < 0.05). The apoptosis rate of intestinal cells in the LP group was significantly higher than those in the LP and HP groups (P < 0.05). The mRNA expression levels of superoxide dismutase (sod), nuclear factor kappa B p65 subunit (nfκb-p65), heat shock protein 70 (hsp70), and inhibitor of NF-κBα (iκba) in the intestine were significantly higher in the LP group than those in the HP and LP-AA groups (P < 0.05). The 16s RNA analysis indicated that EAA supplementation significantly increased the growth of Desulfovibrio and altered the intestinal microflora. The relative abundances of Firmicutes and Cyanobacteria were positively correlated with antioxidant parameters (CAT and T-AOC), whereas Desulfobacterota was negatively correlated with sod and T-AOC. The genera Bacillus, Bacteroides, and Rothia were associated with the favorable maintenance of gut health. In conclusion, dietary supplementation with EAAs to achieve a balanced amino acid profile could potentially reduce the dietary protein levels from 48.66 % to 44.44 % without adversely affecting the growth and intestinal health of juvenile blotched snakeheads.

3.
Emerg Microbes Infect ; 13(1): 2339942, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38584569

RESUMO

To investigate the epidemiology of ST20 carbapenem-resistant Klebsiella pneumoniae (CRKP) in China, and further explore the genomic characteristics of blaIMP-4 and blaNDM-1 coharboring isolates and plasmid contributions to resistance and fitness. Seven ST20 CRKP isolates were collected nationwide, and antimicrobial susceptibility testing was performed. Antimicrobial resistance genes, virulence genes, and plasmid replicons were identified via whole-genome sequencing, and clonality assessed via core-genome multilocus sequence typing. Furthermore, we found four dual-metallo-ß-lactamases (MBL)-harbouring isolates, the gene location was detected by Southern blotting, and plasmid location analysis showed that blaIMP-4 was located on a separate plasmid, a self-conjugative fusion plasmid, or the bacterial chromosome. These isolates were subjected to long-read sequencing, the presence of blaIMP-4 in different locations was identified by genomic comparison, and transposon units were detected via inverse PCR. We subsequently found that blaIMP-4 on the fusion plasmid and bacterial chromosome was formed via intact plasmid recombination by the IS26 and ltrA, respectively, and the circular transposon unit was related to cointegration, however, blaIMP-4 in different locations did not affect the gene stability. The blaNDM-1-harbouring plasmid contributed to the increased resistance to ß-lactams and shortened survival lag time which was revealed in plasmid cured isolates. In summary, the K. pneumoniae ST20 clone is a high-risk resistant clone. With the use of ceftazidime/avibactam, MBL-positive isolates, especially dual-MBL-harbouring isolates, should be given additional attention.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Klebsiella pneumoniae , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Plasmídeos/genética , beta-Lactamases/genética , beta-Lactamases/farmacologia , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Tipagem de Sequências Multilocus , Testes de Sensibilidade Microbiana
4.
J Ethnopharmacol ; : 118194, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38641077

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Prinsepia utilis Royle, native to the Himalayan region, has a long history of use in traditional medicine for its heat-clearing, detoxification, anti-inflammatory, and analgesic properties. Oils extracted from P. utilis seeds are also used in cooking and cosmetics. With the increasing market demand, this extraction process generates substantial industrial biowastes. Recent studies have found many health benefits with using aqueous extracts of these biowastes, which are also rich in polysaccharides. However, there is limited research related to the reparative effects of the water extracts of P. utilis oil cakes (WEPUOC) on disruptions of the skin barrier function. AIM OF THE STUDY: This study aimed to evaluate the reparative efficacy of WEPUOC in both acute and chronic epidermal permeability barrier disruptions. Furthermore, the study sought to explore the underlying mechanisms involved in repairing the epidermal permeability barrier. MATERIALS AND METHODS: Mouse models with induced epidermal disruptions, employing tape-stripping (TS) and acetone wiping (AC) methods, were used. The subsequent application of WEPUOC (100 mg/mL) was evaluated through various assessments, with a focus on the upregulation of mRNA and protein expression of Corneocyte Envelope (CE) related proteins, lipid synthase-associated proteins, and tight junction proteins. RESULTS: The polysaccharide was the major phytochemicals of WEPUOC and its content was determined as 32.2% by the anthranone-sulfuric acid colorimetric method. WEPUOC significantly reduced transepidermal water loss (TEWL) and improved the damaged epidermal barrier in the model group. Mechanistically, these effects were associated with heightened expression levels of key proteins such as FLG (filaggrin), INV (involucrin), LOR (loricrin), SPT, FASN, HMGCR, Claudins-1, Claudins-5, and ZO-1. CONCLUSIONS: WEPUOC, obtained from the oil cakes of P. utilis, is rich in polysaccharides and exhibits pronounced efficacy in repairing disrupted epidermal barriers through increased expression of critical proteins involved in barrier integrity. Our findings underscore the potential of P. utilis wastes in developing natural cosmetic prototypes for the treatment of diseases characterized by damaged skin barriers, including atopic dermatitis and psoriasis.

6.
ACS Appl Mater Interfaces ; 16(13): 16132-16144, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38511296

RESUMO

The main impediment to the development of zinc-air batteries is the sluggish kinetics of the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER). Transition metal N-doped carbon catalysts offer a promising alternative to noble metal catalysts, with metal-organic framework (MOF)-derived carbon material catalysts being particularly noteworthy. Here, we synthesized MxP-Z-C carbon catalysts by combining two-dimensional (2D) metal porphyrin-based MOFs (MxPMFs, x = Fe, Co, Ni, Mn) and three-dimensional zeolitic imidazole framework-8 (ZIF-8) through electrostatic interaction, followed by carbonization. ZIF-8 was inserted between the layers of MxPMFs to prevent its Π-Π stacking, allowing the active sites to become fully exposed. MxP-Z-C demonstrated an impressive catalytic activity for both the ORR and the OER reactions. Among them, FeP-Z-C showed the best catalytic activity. The half-wave potential for ORR was 0.92 V (vs the reversible hydrogen electrode (RHE)), while the overpotential for the OER was 290 mV. In addition, the zinc-air battery assembled by FeP-Z-C exhibited high power density (133.14 mW cm-2) and significant specific capacity (816 mAh gZn-1), indicating considerable potential as a bifunctional catalyst for electronic devices.

7.
J Anim Sci ; 1022024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38477672

RESUMO

The accurate identification of individual sheep is a crucial prerequisite for establishing digital sheep farms and precision livestock farming. Currently, deep learning technology provides an efficient and non-contact method for sheep identity recognition. In particular, convolutional neural networks can be used to learn features of sheep faces to determine their corresponding identities. However, the existing sheep face recognition models face problems such as large model size, and high computational costs, making it difficult to meet the requirements of practical applications. In response to these issues, we introduce a lightweight sheep face recognition model called YOLOv7-Sheep Face Recognition (YOLOv7-SFR). Considering the labor-intensive nature associated with manually capturing sheep face images, we developed a face image recording channel to streamline the process and improve efficiency. This study collected facial images of 50 Small-tailed Han sheep through a recording channel. The experimental sheep ranged in age from 1 to 3 yr, with an average weight of 63.1 kg. Employing data augmentation methods further enhanced the original images, resulting in a total of 22,000 sheep face images. Ultimately, a sheep face dataset was established. To achieve lightweight improvement and improve the performance of the recognition model, a variety of improvement strategies were adopted. Specifically, we introduced the shuffle attention module into the backbone and fused the Dyhead module with the model's detection head. By combining multiple attention mechanisms, we improved the model's ability to learn target features. Additionally, the traditional convolutions in the backbone and neck were replaced with depthwise separable convolutions. Finally, leveraging knowledge distillation, we enhanced its performance further by employing You Only Look Once version 7 (YOLOv7) as the teacher model and YOLOv7-SFR as the student model. The training results indicate that our proposed approach achieved the best performance on the sheep face dataset, with a mean average precision@0.5 of 96.9%. The model size and average recognition time were 11.3 MB and 3.6 ms, respectively. Compared to YOLOv7-tiny, YOLOv7-SFR showed a 2.1% improvement in mean average precision@0.5, along with a 5.8% reduction in model size and a 42.9% reduction in average recognition time. The research results are expected to drive the practical applications of sheep face recognition technology.


Accurate identification of individual sheep is a crucial prerequisite for establishing digital sheep farms and precision livestock farming. In this study, we developed a lightweight sheep face recognition model, YOLOv7-SFR. Utilizing a face image recording channel, we efficiently collected facial images from 50 experimental sheep, resulting in a comprehensive sheep face dataset. Training results demonstrated that YOLOv7-SFR surpassed state-of-the-art lightweight sheep face recognition models, achieving a mean average precision@0.5 of 96.9%. Notably, the model size and average recognition time of YOLOv7-SFR were merely 11.3 MB and 3.6 ms, respectively. In summary, YOLOv7-SFR strikes an optimal balance between performance, model size, and recognition speed, offering promising practical applications for sheep face recognition technology. This study employs deep learning for sheep face recognition tasks, ensuring the welfare of sheep in the realm of digital agriculture and automation practices.


Assuntos
Reconhecimento Facial , Trabalho de Parto , Animais , Ovinos , Gravidez , Feminino , Agricultura , Fazendas , Gado
8.
Int J Biol Macromol ; 264(Pt 1): 130508, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38428780

RESUMO

In present study, two water-soluble polysaccharides designated as POL-1 and POL-2 were purified from purslane and their structural characteristics as well as immunomodulatory activity were investigated. The weight-average molecular weight (Mw) of POL-1 and POL-2 were determined to be 64,100 Da and 21,000 Da, respectively. Comprehensive techniques including UV, IR, GC-MS, and NMR were applied to deduced that POL-1 was a pectin polysaccharide homogalacturonan (HG) consisting of →4)-α-GalpA-(1→ with methyl ester degree of 9.71 % and acetylation degree of 0.34 %, while POL-2 was composed of a 1, 4-linked ß-Galp backbone substituted by short side chain →4)-α-Glcp-(1→ and →6)-α-Glcp-(1→. The →4)-α-Glcp-(1→ was attached at the O-6 position of →4)-ß-Galp-(1→. TEM further revealed that POL-1 was non-branched single chains, while POL-2 was entangled microstructure with side chains. Moreover, POL-2 significantly promoted macrophage phagocytosis as well as the secretion of NO and cytokines (TNF-α, IL-6) through activating NF-κB signaling pathway, thus demonstrating potential immunomodulatory activity. These findings suggested that purslane may be exploited as a potential adjuvant and dietary supplement with immunostimulatory purpose.


Assuntos
Portulaca , Portulaca/química , Polissacarídeos/química , Citocinas/metabolismo , Macrófagos/metabolismo , Fagocitose
9.
Pharmacol Res ; 202: 107121, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38431091

RESUMO

Bone homeostasis is maintained by osteoclast-mediated bone resorption and osteoblast-mediated bone formation. A dramatic decrease in estrogen levels in postmenopausal women leads to osteoclast overactivation, impaired bone homeostasis, and subsequent bone loss. Changes in the gut microbiome affect bone mineral density. However, the role of the gut microbiome in estrogen deficiency-induced bone loss and its underlying mechanism remain unknown. In this study, we found that the abundance of Clostridium sporogenes (C. spor.) and its derived metabolite, indole propionic acid (IPA), were decreased in ovariectomized (OVX) mice. In vitro assays suggested that IPA suppressed osteoclast differentiation and function. At the molecular level, IPA suppressed receptor activator of nuclear factor kappa-Β ligand (RANKL)-induced pregnane X receptor (PXR) ubiquitination and degradation, leading to increased binding of remaining PXR with P65. In vivo daily IPA administration or repeated C. spor. colonization protected against OVX-induced bone loss. To protect live bacteria from the harsh gastric environment and delay the emptying of orally administered C. spor. from the intestine, a C. spor.-encapsulated silk fibroin (SF) hydrogel system was developed, which achieved bone protection in OVX mice comparable to that achieved with repeated germ transplantation or daily IPA administration. Overall, we found that gut C. spor.-derived IPA was involved in estrogen deficiency-induced osteoclast overactivation by regulating the PXR/P65 complex. The C. spor.-encapsulated SF hydrogel system is a promising tool for combating postmenopausal osteoporosis without the disadvantages of repeated germ transplantation.


Assuntos
Reabsorção Óssea , Clostridium , Osteoclastos , Propionatos , Humanos , Feminino , Camundongos , Animais , Osteoclastos/metabolismo , Receptor de Pregnano X/metabolismo , Reabsorção Óssea/metabolismo , Osteogênese , Estrogênios/metabolismo , Indóis/metabolismo , Hidrogéis , Ligante RANK/metabolismo , Diferenciação Celular
10.
Artigo em Inglês | MEDLINE | ID: mdl-38546201

RESUMO

OBJECTIVE: Data on the impact of different anesthesia methods on clinical outcomes in patients with acute ischemic stroke undergoing endovascular therapy (EVT) in extended windows are limited. This study compared clinical outcomes in patients with stroke having general anesthesia (GA), conscious sedation (CS), or local anesthesia (LA) during EVT in extended (>6 h) time windows. METHODS: We conducted an exploratory analysis of data from the ANGEL-ACT registry. The primary outcome was the modified Rankin Scale (mRS) score at 90 days. Secondary outcomes included the proportions of patients with mRS scores of 0 to 1, 0 to 2, and 0 to 3, and safety outcomes were any intracranial hemorrhage (ICH), symptomatic ICH, or mortality within 90 days. Multivariate analyses, inverse probability of treatment weighting, and coarsened exact matching were used to adjust for indication bias. RESULTS: A total of 646 patients were included in the analysis (GA,280; CS, 103; LA, 263). Patients having LA during EVT were more likely to have a favorable mRS score (adjusted odds ratio [aOR]: 1.75; 95% CI: 1.28 to 2.40) and a lower incidence of symptomatic ICH (aOR: 0.33; 95% CI: 0.14 to 0.76) than those having GA group. Similarly, CS was associated with greater odds of favorable 90-day mRS scores compared with GA (aOR: 1.69; 95% CI: 1.11 to 2.56). Posterior circulation stroke was overrepresented in the GA group (29.6%) and may be a reason for the worse outcomes in the GA group. CONCLUSIONS: Patients who received LA or CS had better neurological outcomes than those who received GA within extended time windows in a real-world setting.

11.
J Ethnopharmacol ; 328: 118021, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38492793

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Prinsepia utilis Royle, also known as the Anas fruit, is a unique perennial woody oil plant from Yunnan Province, China. In the ancient texts of Dongba sutras and Yunnan Southern Materia Medica, it has been documented that the local Naxi, Tibetan, and Mosuo communities extensively utilize the root and leaf fruits of green thorns for various purposes. These include treating mild-to-moderate specific dermatitis, moisturising the skin, providing protection against UV damage, aiding childbirth in pregnant women, safeguarding stomach health, reducing the risk of arteriosclerosis, and delaying aging. AIM OF THE STUDY: In this study, leftover residues from oil extraction were efficiently reused, and flavonoids were identified during subsequent extraction and separation processes. The anti-senescent effects of flavonoids in P. utilis Royle have not been systematically studied. Therefore, the objective of this study was to explore the anti-senescent properties of the flavonoids obtained from P. utilis Royle. METHODS: First, HPLC and other analytical techniques were used to identify the components of the P. utilis Royle flavonoid (PURF). Next, DPPH, hydroxyl radicals, superoxide anion O2-, collagenase, and elastase were initially detected using in vitro biochemical assays. To examine its antioxidant properties, a zebrafish model was used, and to confirm its anti-senescent effects, a d-galactose-induced mouse aging model was employed. The anti-senescent mechanism of PURF was examined using a natural senescence HFF model. Furthermore, the anti-senescent target was confirmed using a 3D full T-Skin™ model. RESULTS: In vitro biochemical assays demonstrated that flavones exhibited potent antioxidant activity and anti-senescent potential by inhibiting DPPH, hydroxyl radicals, superoxide anion O2-, collagenase, and elastase. It significantly enhanced the antioxidant effect on zebrafish while suppressing ROS and inflammatory injury, up-regulating COL1A1, COL3A1, AMPK, and mTOR gene expression and down-regulating MMP-9, TGF-ß, p21, and p16 gene expression suggesting its potential anti-senescent ability. Findings from the D-galactose-induced aging mouse model showed that PURF greatly increased SOD levels, while simultaneously decreasing HYP and MDA levels. In addition, when PURF was given to the HFF cell and 3D full T-Skin™ model, consistent trends were observed in gene and protein expression, with up-regulation of COL1A1, COL3A1, AMPK, and mTOR genes and down-regulation of TGF-ß, MMP-1, MMP-9, p21, and p16 genes. Therefore, these preliminary findings indicate that flavones can modulate AMPK/mTOR/TGF-ß signalling pathways to exert its influence. CONCLUSION: The kernel residue of natural P. utilis Royle oil extracted from Yunnan province was previously considered agricultural waste, but we successfully extracted and isolated its flavonoid components. Our preliminary studies demonstrated its potential as an environmentally friendly anti-senescent raw material.


Assuntos
Flavonas , Gravidez , Animais , Camundongos , Humanos , Feminino , Flavonas/farmacologia , Metaloproteinase 9 da Matriz , Peixe-Zebra , Superóxidos , Galactose , Proteínas Quinases Ativadas por AMP , China , Antioxidantes/farmacologia , Flavonoides/farmacologia , Sementes , Elastase Pancreática , Fator de Crescimento Transformador beta , Serina-Treonina Quinases TOR
12.
Front Public Health ; 12: 1333910, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38439751

RESUMO

Background: Metabolic syndrome (MetS) is on the rise in developing countries and is characterized by a series of indications of metabolic disturbance. However, the prevalence of MetS varies under different definitions. The study aimed to compare five definitions of MetS in the China adult population, to explore their prevalence, characteristics and agreement. Methods: The data for the retrospective study came from the China Health and Retirement Longitudinal Study (CHARLS), consisting of 9,588 participants (≥45). MetS definitions from International Diabetes Federation (IDF) (2006), National Cholesterol Education Program Adult Treatment Panel III (ATPIII) (2005), National Cholesterol Education Program Adult Treatment Panel III (ATPIII) (2001), Chinese Diabetes society (CDS) (2004) and the World Health Organization (WHO) (1999). We used binary and multivariable logistic analysis to explore factors connected with MetS. Results: The five definitions of MetS led to different prevalence of MetS:34.52% by IDF (2006), 38.63% by ATP (2005), 25.94% by ATP (2001), 26.31% by CDS (2004), 21.57% by WHO (1999). According to the definition of IDF (2006) (22.32% vs. 45.06%), ATPIII (2005) definition (27.99% vs. 47.82%), ATPIII (2001) definition (15.37% vs. 35.07%), CDS (2004) definition (19.96% vs. 31.80%), and WHO (1999) definition (17.44% vs. 25.14%), the prevalence of MetS in men was low but in women was high. The agreement between the five definitions for men was good except for the IDF (2006) definition and ATPIII (2001) definition (kappa = 0.51), with kappa values from 0.64 to 0.85. For women, the agreement between the five definitions was good ranging from 0.67 to 0.95, however, except for the definition of CDS (2004) and the definition of IDF (2006) (kappa = 0.44), the definition of WHO (1999) and the definition of IDF (2006) (kappa = 0.55), and the definition of WHO (1999) and the definition of ATPIII (2005) (kappa = 0.54). Binary logistic analysis indicated that although the impact and relevance varied by sex and definition, age, education, marital status, current residence, current smoking, alcohol using, taking activities and number of chronic diseases were factors connected to MetS. Conclusion: the prevalence and characteristics of the five definitions of MetS are different in the Chinese population. Therefore, it is vital to use the same definition for a country to diagnose MetS. On the other side, a lower prevalence in men than in women and the consistency of five MetS definitions are good in men but relatively poor in women.


Assuntos
Diabetes Mellitus , Síndrome Metabólica , Adulto , Masculino , Feminino , Humanos , Síndrome Metabólica/diagnóstico , Síndrome Metabólica/epidemiologia , Estudos Retrospectivos , Estudos Longitudinais , Prevalência , China/epidemiologia , Colesterol , Trifosfato de Adenosina
13.
Nanomaterials (Basel) ; 14(5)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38470743

RESUMO

The niobium oxide dihalides have recently been identified as a new class of van der Waals materials exhibiting exceptionally large second-order nonlinear optical responses and robust in-plane ferroelectricity. In contrast to second-order nonlinear processes, third-order optical nonlinearities can arise irrespective of whether a crystal lattice is centrosymmetric. Here, we report third harmonic generation (THG) in two-dimensional (2D) transition metal oxide iodides, namely NbOI2 and TaOI2. We observe a comparable THG intensity from both materials. By benchmarking against THG from monolayer WS2, we deduce that the third-order susceptibility is approximately on the same order. THG resonances are revealed at different excitation wavelengths, likely due to enhancement by excitonic states and band edge resonances. The THG intensity increases for material thicknesses up to 30 nm, owing to weak interlayer coupling. After this threshold, it shows saturation or a decrease, due to optical interference effects. Our results establish niobium and tantalum oxide iodides as promising 2D materials for third-order nonlinear optics, with intrinsic in-plane ferroelectricity and thickness-tunable nonlinear efficiency.

14.
Front Psychiatry ; 15: 1328226, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38414504

RESUMO

Background: Insomnia in healthcare workers has become a topic of concern in the health system. The high infectivity and longevity of the COVID-19 pandemic have resulted in great pressure and a high incidence of insomnia among healthcare workers. Insomnia among healthcare workers has a negative impact on high-quality healthcare services in addition to their health. Thus, it's necessary to explore insomnia's underlying mechanisms. Object: The present research's aims were threefold: explored the association between social support, resilience, COVID-19 anxiety, and insomnia among healthcare workers during the pandemic, elucidated the underlying mechanism of insomnia, and offered recommendations for improving the health of these workers. Materials and methods: A cross-sectional design was adopted. From May 20 to 30, 2022, 1038 healthcare workers were selected to fill out the Oslo 3-item Social Support Scale, the eight-item Athens Insomnia Scale, the Coronavirus Anxiety Scale, and the Brief Resilience Scale. Descriptive statistics and correlations were analyzed by SPSS 25.0. Mediation analysis was conducted by Mplus 8.3 using 5000 bootstrap samples. Results: Of the participating 1038 healthcare workers, the prevalence of insomnia was 41.62% (432/1038). Significant associations were found involving insomnia, resilience, COVID-19 anxiety, and social support. Insomnia was directly affected by social support. Moreover, three indirect pathways explain how social support affected insomnia: resilience's mediating role, COVID-19 anxiety's mediating role, and the chain-mediation role of resilience and COVID-19 anxiety. Conclusion: The results validated our hypotheses and supported the opinion of Spielman et al. 's three-factor model of insomnia. Social support of healthcare workers has an indirect impact on insomnia in addition to its direct one via independent and chain-mediation effects of resilience and COVID-19 anxiety.

15.
Nano Lett ; 24(6): 1851-1858, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38315876

RESUMO

Interlayer excitons, with prolonged lifetimes and tunability, hold potential for advanced optoelectronics. Previous research on the interlayer excitons has been dominated by two-dimensional heterostructures. Here, we construct WSe2/GaN composite heterostructures, in which the doping concentration of GaN and the twist angle of bilayer WSe2 are employed as two ingredients for the manipulation of exciton behaviors and polarizations. The exciton energies in monolayer WSe2/GaN can be regulated continuously by the doping levels of the GaN substrate, and a remarkable increase in the valley polarizations is achieved. Especially in a heterostructure with 4°-twisted bilayer WSe2, a maximum polarization of 38.9% with a long lifetime is achieved for the interlayer exciton. Theoretical calculations reveal that the large polarization and long lifetime are attributed to the high exciton binding energy and large spin flipping energy during depolarization in bilayer WSe2/GaN. This work introduces a distinctive member of the interlayer exciton with a high degree of polarization and a long lifetime.

16.
Chemosphere ; 353: 141503, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382718

RESUMO

Recently, water contamination caused by the misuse of antibiotics has become a growing concern. In this study, an economical chitin/calcite composite (CCA) was extracted from crab shell waste, and the effects and mechanisms of its removal of ciprofloxacin (CIP) and tetracycline (TC) from aqueous solution were investigated. The functional groups of chitin and the metal phase of calcite gave CCA the ability to remove antibiotics. Experiments on kinetics, isothermal adsorption, thermodynamics, co-removal, and reusability were conducted to systematically explore the adsorption performances of CCA toward antibiotics. The pseudo-second-order (FSO) and Langmuir models suited the data obtained from experiments best and displayed a good fit for the chemisorption and a certain homogeneity of adsorption sites. At 25 °C, the maximum adsorption capacities (Qmax) toward CIP and TC were 228.86 and 150.76 mg g-1, respectively. The adsorption mechanisms of CCA with TC and CIP are pH dependent since pH can affect the surface charge of CCA and the form in which CIP and TC are existing. The X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) demonstrated that the keto-O and carboxyl groups of CIP and the carbonyl, hydroxyl, and amido groups of TC could be responsible for the binding with the calcite and the functional groups of chitin through surface complexation, cation bridge and hydrogen bonding.


Assuntos
Ciprofloxacina , Poluentes Químicos da Água , Ciprofloxacina/química , Carbonato de Cálcio , Quitina , Antibacterianos/química , Tetraciclina/química , Poluentes Químicos da Água/análise , Adsorção , Cinética , Concentração de Íons de Hidrogênio , Espectroscopia de Infravermelho com Transformada de Fourier
17.
Emerg Microbes Infect ; 13(1): 2324068, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38406830

RESUMO

Ceftazidime-avibactam (CZA) resistance is a huge threat in the clinic; however, the underlying mechanism responsible for high-level CZA resistance in Pseudomonas aeruginosa (PA) isolates remains unknown. In this study, a total of 5,763 P. aeruginosa isolates were collected from 2010 to 2022 to investigate the ceftazidime-avibactam (CZA) high-level resistance mechanisms of Pseudomonas aeruginosa (PA) isolates in China. Fifty-six PER-producing isolates were identified, including 50 isolates carrying blaPER-1 in PA, and 6 isolates carrying blaPER-4. Of these, 82.1% (46/56) were classified as DTR-PA isolates, and 76.79% (43/56) were resistant to CZA. Importantly, blaPER-1 and blaPER-4 overexpression led to 16-fold and >1024-fold increases in the MICs of CZA, respectively. WGS revealed that the blaPER-1 gene was located in two different transferable IncP-2-type plasmids and chromosomes, whereas blaPER-4 was found only on chromosomes and was carried by a class 1 integron embedded in a Tn6485-like transposon. Overexpression of efflux pumps may be associated with high-level CZA resistance in blaPER-1-positive strains. Kinetic parameter analysis revealed that PER-4 exhibited a similar kcat/Km with ceftazidime and a high (∼3359-fold) IC50 value with avibactam compared to PER-1. Our study found that overexpression of PER-1 combined with enhanced efflux pump expression and the low affinity of PER-4 for avibactam contributes to high-level resistance to CZA. Additionally, the Tn6485-like transposon plays a significant role in disseminating blaPER. Urgent active surveillance is required to prevent the further spread of high-level CZA resistance in DTR-PA isolates.


Assuntos
Compostos Azabicíclicos , Ceftazidima , Infecções por Pseudomonas , Humanos , Ceftazidima/farmacologia , Pseudomonas aeruginosa/genética , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Infecções por Pseudomonas/epidemiologia , Combinação de Medicamentos , Genômica , Testes de Sensibilidade Microbiana , beta-Lactamases/genética
18.
BMC Med Educ ; 24(1): 118, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321409

RESUMO

BACKGROUND: Nurses play an important role in healthcare development. The increasing demands for nurses mean that nursing schools at the undergraduate level have the responsibility to ensure patient safety and quality care through a well-designed curriculum. This research aimed to evaluate the effect of the teaching method combined with situational awareness and case-based seminars in a comprehensive nursing skills practice course on the level of self-directed learning, professional identity, academic self-efficacy, theoretical scores, practical scores, teaching satisfaction, and student competence among nursing students. METHODS: The research population comprised was of the grades of 2019 and 2020 at Wannan Medical College in Anhui Province, China (n = 169, response rate 77.88%). The observation group from grade 2020 used the teaching method combined with situational awareness and case-based seminars, whereas the control group from grade 2019 used the traditional teaching mode. General information, self-directed learning, a professional identity, and academic self-efficacy were compared between the two groups. This research used means and standard deviations, chi-square, the Shapiro-Wilk test, and an independent sample t-test for statistical analyses. RESULTS: Compared with the control group, the total scores for self-directed learning, professional identity, and academic self-efficacy were higher in the observation group (78.80 ± 7.89 vs 60.21 ± 7.44, 63.39 ± 7.87 vs 52.35 ± 7.68, and 22.31 ± 3.30 vs 21.28 ± 2.31, respectively, with P < 0.05 for all scores). More significant improvements were made in the observation group on the level of theoretical scores (81.39 ± 3.32 vs 76.28 ± 5.90) and practical scores (93.32 ± 4.70 vs 90.67 ± 5.09) (P < 0.05). Meanwhile, teaching satisfaction, which includes teaching method (66/18 vs 32/53) and teacher-student interaction (72/12 vs 34/51), and student competence, which includes team cooperation (67/17 vs 39/46), critical thinking (60/24 vs 31/54), and communication skills (67/17 vs 38/47) after the intervention (P < 0.05). There was no significant difference in social persuasion (P > 0.05). CONCLUSION: The teaching method combined with situational awareness and case-based seminars in a comprehensive nursing skills practice course has the potential to improve the level of self-directed learning, professional identity, and academic self-efficacy, and it increases theoretical scores, practical scores, teaching satisfaction, and student competence.


Assuntos
Bacharelado em Enfermagem , Estudantes de Enfermagem , Humanos , Conscientização , Bacharelado em Enfermagem/métodos , Aprendizagem , Currículo
19.
Animals (Basel) ; 14(3)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38338134

RESUMO

Figla is one of the earliest expressed genes in the oocyte during ovarian development. In this study, Figla was characterized in C. maculata, one of the main aquaculture species in China, and designated as CmFigla. The length of CmFigla cDNA was 1303 bp, encoding 197 amino acids that contained a conserved bHLH domain. CmFigla revealed a female-biased expression patterns in the gonads of adult fish, and CmFigla expression was far higher in ovaries than that in testes at all gonadal development stages, especially at 60~180 days post-fertilization (dpf). Furthermore, a noteworthy inverse relationship was observed between CmFigla expression and the methylation of its promoter in the adult gonads. Gonads at 90 dpf were used for in situ hybridization (ISH), and CmFigla transcripts were mainly concentrated in oogonia and the primary oocytes in ovaries, but undetectable in the testes. These results indicated that Figla would play vital roles in the ovarian development in C. maculata. Additionally, the frame-shift mutations of CmFigla were successfully constructed through the CRISPR/Cas9 system, which established a positive foundation for further investigation on the role of Figla in the ovarian development of C. maculata. Our study provides valuable clues for exploring the regulatory mechanism of Figla in the fish ovarian development and maintenance, which would be useful for the sex control and reproduction of fish in aquaculture.

20.
ACS Nano ; 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38315123

RESUMO

Rapid advancements in human-machine interaction and voice biometrics impose desirability on soft mechanical sensors for sensing complex dynamic signals. However, existing soft mechanical sensors mainly concern quasi-static signals such as pressure and pulsation for health monitoring, limiting their applications in emerging wearable electronics. Here, we propose a hydrogel-based soft mechanical sensor that enables recording a wide range of dynamic signals relevant to humans by combining a preloading design strategy and iontronic sensing mechanism. The proposed sensor offers a two-orders-of-magnitude larger working bandwidth (up to 1000 Hz) than most of the reported soft mechanical sensors and meanwhile provides a high sensitivity (-23 dB) that surpasses the common commercial microphone. The amplitude-frequency characteristic of the proposed sensor can be precisely tuned to meet the desired requirement by adjusting the preloads and the parameters of the microstructured hydrogel. The sensor is capable of recording instrumental sounds with high fidelity from simple pure tones to melodic songs. Demonstration of a skin-mountable sensor used for human-voice-based remote control of a toy car shows great potential for applications in the voice user interface of human-machine interactions.

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